Astrocytoma: Neoplasms of the brain and spinal cord derived from glial cells which vary from histologically benign forms to highly anaplastic and malignant tumors. Fibrillary astrocytomas are the most common type and may be classified in order of increasing malignancy (grades I through IV). In the first two decades of life, astrocytomas tend to originate in the cerebellar hemispheres; in adults, they most frequently arise in the cerebrum and frequently undergo malignant transformation. (From Devita et al., Cancer: Principles and Practice of Oncology, 5th ed, pp2013-7; Holland et al., Cancer Medicine, 3d ed, p1082)Brain Neoplasms: Neoplasms of the intracranial components of the central nervous system, including the cerebral hemispheres, basal ganglia, hypothalamus, thalamus, brain stem, and cerebellum. Brain neoplasms are subdivided into primary (originating from brain tissue) and secondary (i.e., metastatic) forms. Primary neoplasms are subdivided into benign and malignant forms. In general, brain tumors may also be classified by age of onset, histologic type, or presenting location in the brain.Glioma: Benign and malignant central nervous system neoplasms derived from glial cells (i.e., astrocytes, oligodendrocytes, and ependymocytes). Astrocytes may give rise to astrocytomas (ASTROCYTOMA) or glioblastoma multiforme (see GLIOBLASTOMA). Oligodendrocytes give rise to oligodendrogliomas (OLIGODENDROGLIOMA) and ependymocytes may undergo transformation to become EPENDYMOMA; CHOROID PLEXUS NEOPLASMS; or colloid cysts of the third ventricle. (From Escourolle et al., Manual of Basic Neuropathology, 2nd ed, p21)Glioblastoma: A malignant form of astrocytoma histologically characterized by pleomorphism of cells, nuclear atypia, microhemorrhage, and necrosis. They may arise in any region of the central nervous system, with a predilection for the cerebral hemispheres, basal ganglia, and commissural pathways. Clinical presentation most frequently occurs in the fifth or sixth decade of life with focal neurologic signs or seizures.Brain Chemistry: Changes in the amounts of various chemicals (neurotransmitters, receptors, enzymes, and other metabolites) specific to the area of the central nervous system contained within the head. These are monitored over time, during sensory stimulation, or under different disease states.Medulloblastoma: A malignant neoplasm that may be classified either as a glioma or as a primitive neuroectodermal tumor of childhood (see NEUROECTODERMAL TUMOR, PRIMITIVE). The tumor occurs most frequently in the first decade of life with the most typical location being the cerebellar vermis. Histologic features include a high degree of cellularity, frequent mitotic figures, and a tendency for the cells to organize into sheets or form rosettes. Medulloblastoma have a high propensity to spread throughout the craniospinal intradural axis. (From DeVita et al., Cancer: Principles and Practice of Oncology, 5th ed, pp2060-1)Cell Line, Tumor: A cell line derived from cultured tumor cells.Meningioma: A relatively common neoplasm of the CENTRAL NERVOUS SYSTEM that arises from arachnoidal cells. The majority are well differentiated vascular tumors which grow slowly and have a low potential to be invasive, although malignant subtypes occur. Meningiomas have a predilection to arise from the parasagittal region, cerebral convexity, sphenoidal ridge, olfactory groove, and SPINAL CANAL. (From DeVita et al., Cancer: Principles and Practice of Oncology, 5th ed, pp2056-7)Oligodendroglioma: A relatively slow-growing glioma that is derived from oligodendrocytes and tends to occur in the cerebral hemispheres, thalamus, or lateral ventricle. They may present at any age, but are most frequent in the third to fifth decades, with an earlier incidence peak in the first decade. Histologically, these tumors are encapsulated, relatively avascular, and tend to form cysts and microcalcifications. Neoplastic cells tend to have small round nuclei surrounded by unstained nuclei. The tumors may vary from well-differentiated to highly anaplastic forms. (From DeVita et al., Cancer: Principles and Practice of Oncology, 5th ed, p2052; Adams et al., Principles of Neurology, 6th ed, p655)Tumor Markers, Biological: Molecular products metabolized and secreted by neoplastic tissue and characterized biochemically in cells or body fluids. They are indicators of tumor stage and grade as well as useful for monitoring responses to treatment and predicting recurrence. Many chemical groups are represented including hormones, antigens, amino and nucleic acids, enzymes, polyamines, and specific cell membrane proteins and lipids.Magnetic Resonance Imaging: Non-invasive method of demonstrating internal anatomy based on the principle that atomic nuclei in a strong magnetic field absorb pulses of radiofrequency energy and emit them as radiowaves which can be reconstructed into computerized images. The concept includes proton spin tomographic techniques.Ependymoma: Glioma derived from EPENDYMOGLIAL CELLS that tend to present as malignant intracranial tumors in children and as benign intraspinal neoplasms in adults. It may arise from any level of the ventricular system or central canal of the spinal cord. Intracranial ependymomas most frequently originate in the FOURTH VENTRICLE and histologically are densely cellular tumors which may contain ependymal tubules and perivascular pseudorosettes. Spinal ependymomas are usually benign papillary or myxopapillary tumors. (From DeVita et al., Principles and Practice of Oncology, 5th ed, p2018; Escourolle et al., Manual of Basic Neuropathology, 2nd ed, pp28-9)Hypothalamic Neoplasms: Benign and malignant tumors of the HYPOTHALAMUS. Pilocytic astrocytomas and hamartomas are relatively frequent histologic types. Neoplasms of the hypothalamus frequently originate from adjacent structures, including the OPTIC CHIASM, optic nerve (see OPTIC NERVE NEOPLASMS), and pituitary gland (see PITUITARY NEOPLASMS). Relatively frequent clinical manifestations include visual loss, developmental delay, macrocephaly, and precocious puberty. (From Devita et al., Cancer: Principles and Practice of Oncology, 5th ed, p2051)Brain Injuries: Acute and chronic (see also BRAIN INJURIES, CHRONIC) injuries to the brain, including the cerebral hemispheres, CEREBELLUM, and BRAIN STEM. Clinical manifestations depend on the nature of injury. Diffuse trauma to the brain is frequently associated with DIFFUSE AXONAL INJURY or COMA, POST-TRAUMATIC. Localized injuries may be associated with NEUROBEHAVIORAL MANIFESTATIONS; HEMIPARESIS, or other focal neurologic deficits.Cerebellar Neoplasms: Primary or metastatic neoplasms of the CEREBELLUM. Tumors in this location frequently present with ATAXIA or signs of INTRACRANIAL HYPERTENSION due to obstruction of the fourth ventricle. Common primary cerebellar tumors include fibrillary ASTROCYTOMA and cerebellar HEMANGIOBLASTOMA. The cerebellum is a relatively common site for tumor metastases from the lung, breast, and other distant organs. (From Okazaki & Scheithauer, Atlas of Neuropathology, 1988, p86 and p141)Supratentorial Neoplasms: Primary and metastatic (secondary) tumors of the brain located above the tentorium cerebelli, a fold of dura mater separating the CEREBELLUM and BRAIN STEM from the cerebral hemispheres and DIENCEPHALON (i.e., THALAMUS and HYPOTHALAMUS and related structures). In adults, primary neoplasms tend to arise in the supratentorial compartment, whereas in children they occur more frequently in the infratentorial space. Clinical manifestations vary with the location of the lesion, but SEIZURES; APHASIA; HEMIANOPSIA; hemiparesis; and sensory deficits are relatively common features. Metastatic supratentorial neoplasms are frequently multiple at the time of presentation.Brain: The part of CENTRAL NERVOUS SYSTEM that is contained within the skull (CRANIUM). Arising from the NEURAL TUBE, the embryonic brain is comprised of three major parts including PROSENCEPHALON (the forebrain); MESENCEPHALON (the midbrain); and RHOMBENCEPHALON (the hindbrain). The developed brain consists of CEREBRUM; CEREBELLUM; and other structures in the BRAIN STEM.Tumor Necrosis Factor-alpha: Serum glycoprotein produced by activated MACROPHAGES and other mammalian MONONUCLEAR LEUKOCYTES. It has necrotizing activity against tumor cell lines and increases ability to reject tumor transplants. Also known as TNF-alpha, it is only 30% homologous to TNF-beta (LYMPHOTOXIN), but they share TNF RECEPTORS.Meningeal Neoplasms: Benign and malignant neoplastic processes that arise from or secondarily involve the meningeal coverings of the brain and spinal cord.Tumor Burden: The total amount (cell number, weight, size or volume) of tumor cells or tissue in the body.Gliosarcoma: Rare mixed tumors of the brain and rarely the spinal cord which contain malignant neuroectodermal (glial) and mesenchymal components, including spindle-shaped fibrosarcoma cells. These tumors are highly aggressive and present primarily in adults as rapidly expanding mass lesions. They may arise in tissue that has been previously irradiated. (From Br J Neurosurg 1995 Apr;9(2):171-8)Optic Nerve Neoplasms: Benign and malignant neoplasms that arise from the optic nerve or its sheath. OPTIC NERVE GLIOMA is the most common histologic type. Optic nerve neoplasms tend to cause unilateral visual loss and an afferent pupillary defect and may spread via neural pathways to the brain.Brain Mapping: Imaging techniques used to colocalize sites of brain functions or physiological activity with brain structures.Spinal Cord Neoplasms: Benign and malignant neoplasms which occur within the substance of the spinal cord (intramedullary neoplasms) or in the space between the dura and spinal cord (intradural extramedullary neoplasms). The majority of intramedullary spinal tumors are primary CNS neoplasms including ASTROCYTOMA; EPENDYMOMA; and LIPOMA. Intramedullary neoplasms are often associated with SYRINGOMYELIA. The most frequent histologic types of intradural-extramedullary tumors are MENINGIOMA and NEUROFIBROMA.Neoplasms, Experimental: Experimentally induced new abnormal growth of TISSUES in animals to provide models for studying human neoplasms.Genes, Tumor Suppressor: Genes that inhibit expression of the tumorigenic phenotype. They are normally involved in holding cellular growth in check. When tumor suppressor genes are inactivated or lost, a barrier to normal proliferation is removed and unregulated growth is possible.Tumor Suppressor Protein p53: Nuclear phosphoprotein encoded by the p53 gene (GENES, P53) whose normal function is to control CELL PROLIFERATION and APOPTOSIS. A mutant or absent p53 protein has been found in LEUKEMIA; OSTEOSARCOMA; LUNG CANCER; and COLORECTAL CANCER.Astrocytes: A class of large neuroglial (macroglial) cells in the central nervous system - the largest and most numerous neuroglial cells in the brain and spinal cord. Astrocytes (from "star" cells) are irregularly shaped with many long processes, including those with "end feet" which form the glial (limiting) membrane and directly and indirectly contribute to the BLOOD-BRAIN BARRIER. They regulate the extracellular ionic and chemical environment, and "reactive astrocytes" (along with MICROGLIA) respond to injury.Immunohistochemistry: Histochemical localization of immunoreactive substances using labeled antibodies as reagents.Tumor Suppressor Proteins: Proteins that are normally involved in holding cellular growth in check. Deficiencies or abnormalities in these proteins may lead to unregulated cell growth and tumor development.Neuroectodermal Tumors, Primitive: A group of malignant tumors of the nervous system that feature primitive cells with elements of neuronal and/or glial differentiation. Use of this term is limited by some authors to central nervous system tumors and others include neoplasms of similar origin which arise extracranially (i.e., NEUROECTODERMAL TUMORS, PRIMITIVE, PERIPHERAL). This term is also occasionally used as a synonym for MEDULLOBLASTOMA. In general, these tumors arise in the first decade of life and tend to be highly malignant. (From DeVita et al., Cancer: Principles and Practice of Oncology, 5th ed, p2059)Wilms Tumor: A malignant kidney tumor, caused by the uncontrolled multiplication of renal stem (blastemal), stromal (STROMAL CELLS), and epithelial (EPITHELIAL CELLS) elements. However, not all three are present in every case. Several genes or chromosomal areas have been associated with Wilms tumor which is usually found in childhood as a firm lump in a child's side or ABDOMEN.Brain Stem Neoplasms: Benign and malignant intra-axial tumors of the MESENCEPHALON; PONS; or MEDULLA OBLONGATA of the BRAIN STEM. Primary and metastatic neoplasms may occur in this location. Clinical features include ATAXIA, cranial neuropathies (see CRANIAL NERVE DISEASES), NAUSEA, hemiparesis (see HEMIPLEGIA), and quadriparesis. Primary brain stem neoplasms are more frequent in children. Histologic subtypes include GLIOMA; HEMANGIOBLASTOMA; GANGLIOGLIOMA; and EPENDYMOMA.Neovascularization, Pathologic: A pathologic process consisting of the proliferation of blood vessels in abnormal tissues or in abnormal positions.Blood-Brain Barrier: Specialized non-fenestrated tightly-joined ENDOTHELIAL CELLS with TIGHT JUNCTIONS that form a transport barrier for certain substances between the cerebral capillaries and the BRAIN tissue.Central Nervous System Neoplasms: Benign and malignant neoplastic processes that arise from or secondarily involve the brain, spinal cord, or meninges.RNA, Messenger: RNA sequences that serve as templates for protein synthesis. Bacterial mRNAs are generally primary transcripts in that they do not require post-transcriptional processing. Eukaryotic mRNA is synthesized in the nucleus and must be exported to the cytoplasm for translation. Most eukaryotic mRNAs have a sequence of polyadenylic acid at the 3' end, referred to as the poly(A) tail. The function of this tail is not known for certain, but it may play a role in the export of mature mRNA from the nucleus as well as in helping stabilize some mRNA molecules by retarding their degradation in the cytoplasm.Cell Proliferation: All of the processes involved in increasing CELL NUMBER including CELL DIVISION.Tumor Cells, Cultured: Cells grown in vitro from neoplastic tissue. If they can be established as a TUMOR CELL LINE, they can be propagated in cell culture indefinitely.Time Factors: Elements of limited time intervals, contributing to particular results or situations.Nimustine: Antineoplastic agent especially effective against malignant brain tumors. The resistance which brain tumor cells acquire to the initial effectiveness of this drug can be partially overcome by the simultaneous use of membrane-modifying agents such as reserpine, calcium antagonists such as nicardipine or verapamil, or the calmodulin inhibitor, trifluoperazine. The drug has also been used in combination with other antineoplastic agents or with radiotherapy for the treatment of various neoplasms.Transplantation, Heterologous: Transplantation between animals of different species.Brain Edema: Increased intracellular or extracellular fluid in brain tissue. Cytotoxic brain edema (swelling due to increased intracellular fluid) is indicative of a disturbance in cell metabolism, and is commonly associated with hypoxic or ischemic injuries (see HYPOXIA, BRAIN). An increase in extracellular fluid may be caused by increased brain capillary permeability (vasogenic edema), an osmotic gradient, local blockages in interstitial fluid pathways, or by obstruction of CSF flow (e.g., obstructive HYDROCEPHALUS). (From Childs Nerv Syst 1992 Sep; 8(6):301-6)Carcinoid Tumor: A usually small, slow-growing neoplasm composed of islands of rounded, oxyphilic, or spindle-shaped cells of medium size, with moderately small vesicular nuclei, and covered by intact mucosa with a yellow cut surface. The tumor can occur anywhere in the gastrointestinal tract (and in the lungs and other sites); approximately 90% arise in the appendix. It is now established that these tumors are of neuroendocrine origin and derive from a primitive stem cell. (From Stedman, 25th ed & Holland et al., Cancer Medicine, 3d ed, p1182)Tumor Microenvironment: The milieu surrounding neoplasms consisting of cells, vessels, soluble factors, and molecules, that can influence and be influenced by, the neoplasm's growth.Neoplasm Recurrence, Local: The local recurrence of a neoplasm following treatment. It arises from microscopic cells of the original neoplasm that have escaped therapeutic intervention and later become clinically visible at the original site.Neoplasm Transplantation: Experimental transplantation of neoplasms in laboratory animals for research purposes.Dacarbazine: An antineoplastic agent. It has significant activity against melanomas. (from Martindale, The Extra Pharmacopoeia, 31st ed, p564)Antineoplastic Agents, Alkylating: A class of drugs that differs from other alkylating agents used clinically in that they are monofunctional and thus unable to cross-link cellular macromolecules. Among their common properties are a requirement for metabolic activation to intermediates with antitumor efficacy and the presence in their chemical structures of N-methyl groups, that after metabolism, can covalently modify cellular DNA. The precise mechanisms by which each of these drugs acts to kill tumor cells are not completely understood. (From AMA, Drug Evaluations Annual, 1994, p2026)Mice, Inbred C57BLDisease Models, Animal: Naturally occurring or experimentally induced animal diseases with pathological processes sufficiently similar to those of human diseases. They are used as study models for human diseases.Gene Expression Regulation, Neoplastic: Any of the processes by which nuclear, cytoplasmic, or intercellular factors influence the differential control of gene action in neoplastic tissue.Brain Abscess: A circumscribed collection of purulent exudate in the brain, due to bacterial and other infections. The majority are caused by spread of infected material from a focus of suppuration elsewhere in the body, notably the PARANASAL SINUSES, middle ear (see EAR, MIDDLE); HEART (see also ENDOCARDITIS, BACTERIAL), and LUNG. Penetrating CRANIOCEREBRAL TRAUMA and NEUROSURGICAL PROCEDURES may also be associated with this condition. Clinical manifestations include HEADACHE; SEIZURES; focal neurologic deficits; and alterations of consciousness. (Adams et al., Principles of Neurology, 6th ed, pp712-6)Blotting, Western: Identification of proteins or peptides that have been electrophoretically separated by blot transferring from the electrophoresis gel to strips of nitrocellulose paper, followed by labeling with antibody probes.Carmustine: A cell-cycle phase nonspecific alkylating antineoplastic agent. It is used in the treatment of brain tumors and various other malignant neoplasms. (From Martindale, The Extra Pharmacopoeia, 30th ed, p462) This substance may reasonably be anticipated to be a carcinogen according to the Fourth Annual Report on Carcinogens (NTP 85-002, 1985). (From Merck Index, 11th ed)Tomography, X-Ray Computed: Tomography using x-ray transmission and a computer algorithm to reconstruct the image.Disease Progression: The worsening of a disease over time. This concept is most often used for chronic and incurable diseases where the stage of the disease is an important determinant of therapy and prognosis.Signal Transduction: The intracellular transfer of information (biological activation/inhibition) through a signal pathway. In each signal transduction system, an activation/inhibition signal from a biologically active molecule (hormone, neurotransmitter) is mediated via the coupling of a receptor/enzyme to a second messenger system or to an ion channel. Signal transduction plays an important role in activating cellular functions, cell differentiation, and cell proliferation. Examples of signal transduction systems are the GAMMA-AMINOBUTYRIC ACID-postsynaptic receptor-calcium ion channel system, the receptor-mediated T-cell activation pathway, and the receptor-mediated activation of phospholipases. Those coupled to membrane depolarization or intracellular release of calcium include the receptor-mediated activation of cytotoxic functions in granulocytes and the synaptic potentiation of protein kinase activation. Some signal transduction pathways may be part of larger signal transduction pathways; for example, protein kinase activation is part of the platelet activation signal pathway.Xenograft Model Antitumor Assays: In vivo methods of screening investigative anticancer drugs, biologic response modifiers or radiotherapies. Human tumor tissue or cells are transplanted into mice or rats followed by tumor treatment regimens. A variety of outcomes are monitored to assess antitumor effectiveness.Neuroendocrine Tumors: Tumors whose cells possess secretory granules and originate from the neuroectoderm, i.e., the cells of the ectoblast or epiblast that program the neuroendocrine system. Common properties across most neuroendocrine tumors include ectopic hormone production (often via APUD CELLS), the presence of tumor-associated antigens, and isozyme composition.Neoplasm Proteins: Proteins whose abnormal expression (gain or loss) are associated with the development, growth, or progression of NEOPLASMS. Some neoplasm proteins are tumor antigens (ANTIGENS, NEOPLASM), i.e. they induce an immune reaction to their tumor. Many neoplasm proteins have been characterized and are used as tumor markers (BIOMARKERS, TUMOR) when they are detectable in cells and body fluids as monitors for the presence or growth of tumors. Abnormal expression of ONCOGENE PROTEINS is involved in neoplastic transformation, whereas the loss of expression of TUMOR SUPPRESSOR PROTEINS is involved with the loss of growth control and progression of the neoplasm.Mice, Nude: Mutant mice homozygous for the recessive gene "nude" which fail to develop a thymus. They are useful in tumor studies and studies on immune responses.Cell Division: The fission of a CELL. It includes CYTOKINESIS, when the CYTOPLASM of a cell is divided, and CELL NUCLEUS DIVISION.Neurosurgical Procedures: Surgery performed on the nervous system or its parts.Glial Fibrillary Acidic Protein: An intermediate filament protein found only in glial cells or cells of glial origin. MW 51,000.Nervous System Neoplasms: Benign and malignant neoplastic processes arising from or involving components of the central, peripheral, and autonomic nervous systems, cranial nerves, and meninges. Included in this category are primary and metastatic nervous system neoplasms.Ganglioglioma: Rare indolent tumors comprised of neoplastic glial and neuronal cells which occur primarily in children and young adults. Benign lesions tend to be associated with long survival unless the tumor degenerates into a histologically malignant form. They tend to occur in the optic nerve and white matter of the brain and spinal cord.Mutation: Any detectable and heritable change in the genetic material that causes a change in the GENOTYPE and which is transmitted to daughter cells and to succeeding generations.Cell Transformation, Neoplastic: Cell changes manifested by escape from control mechanisms, increased growth potential, alterations in the cell surface, karyotypic abnormalities, morphological and biochemical deviations from the norm, and other attributes conferring the ability to invade, metastasize, and kill.Brain Stem: The part of the brain that connects the CEREBRAL HEMISPHERES with the SPINAL CORD. It consists of the MESENCEPHALON; PONS; and MEDULLA OBLONGATA.Anaplasia: Loss of structural differentiation and useful function of neoplastic cells.Craniotomy: Any operation on the cranium or incision into the cranium. (Dorland, 28th ed)Combined Modality Therapy: The treatment of a disease or condition by several different means simultaneously or sequentially. Chemoimmunotherapy, RADIOIMMUNOTHERAPY, chemoradiotherapy, cryochemotherapy, and SALVAGE THERAPY are seen most frequently, but their combinations with each other and surgery are also used.DNA, Neoplasm: DNA present in neoplastic tissue.Treatment Outcome: Evaluation undertaken to assess the results or consequences of management and procedures used in combating disease in order to determine the efficacy, effectiveness, safety, and practicability of these interventions in individual cases or series.Antigens, Neoplasm: Proteins, glycoprotein, or lipoprotein moieties on surfaces of tumor cells that are usually identified by monoclonal antibodies. Many of these are of either embryonic or viral origin.Reverse Transcriptase Polymerase Chain Reaction: A variation of the PCR technique in which cDNA is made from RNA via reverse transcription. The resultant cDNA is then amplified using standard PCR protocols.Cell Line: Established cell cultures that have the potential to propagate indefinitely.Antineoplastic Agents: Substances that inhibit or prevent the proliferation of NEOPLASMS.Neoplasm Metastasis: The transfer of a neoplasm from one organ or part of the body to another remote from the primary site.Neoplasms: New abnormal growth of tissue. Malignant neoplasms show a greater degree of anaplasia and have the properties of invasion and metastasis, compared to benign neoplasms.Rats, Inbred F344Molecular Sequence Data: Descriptions of specific amino acid, carbohydrate, or nucleotide sequences which have appeared in the published literature and/or are deposited in and maintained by databanks such as GENBANK, European Molecular Biology Laboratory (EMBL), National Biomedical Research Foundation (NBRF), or other sequence repositories.Tissue Distribution: Accumulation of a drug or chemical substance in various organs (including those not relevant to its pharmacologic or therapeutic action). This distribution depends on the blood flow or perfusion rate of the organ, the ability of the drug to penetrate organ membranes, tissue specificity, protein binding. The distribution is usually expressed as tissue to plasma ratios.Neuronavigation: Intraoperative computer-assisted 3D navigation and guidance system generally used in neurosurgery for tracking surgical tools and localize them with respect to the patient's 3D anatomy. The pre-operative diagnostic scan is used as a reference and is transferred onto the operative field during surgery.Mammary Neoplasms, Experimental: Experimentally induced mammary neoplasms in animals to provide a model for studying human BREAST NEOPLASMS.Mice, Inbred BALB CBrain Ischemia: Localized reduction of blood flow to brain tissue due to arterial obstruction or systemic hypoperfusion. This frequently occurs in conjunction with brain hypoxia (HYPOXIA, BRAIN). Prolonged ischemia is associated with BRAIN INFARCTION.Neoplastic Stem Cells: Highly proliferative, self-renewing, and colony-forming stem cells which give rise to NEOPLASMS.Mice, SCID: Mice homozygous for the mutant autosomal recessive gene "scid" which is located on the centromeric end of chromosome 16. These mice lack mature, functional lymphocytes and are thus highly susceptible to lethal opportunistic infections if not chronically treated with antibiotics. The lack of B- and T-cell immunity resembles severe combined immunodeficiency (SCID) syndrome in human infants. SCID mice are useful as animal models since they are receptive to implantation of a human immune system producing SCID-human (SCID-hu) hematochimeric mice.Cell Survival: The span of viability of a cell characterized by the capacity to perform certain functions such as metabolism, growth, reproduction, some form of responsiveness, and adaptability.Survival Analysis: A class of statistical procedures for estimating the survival function (function of time, starting with a population 100% well at a given time and providing the percentage of the population still well at later times). The survival analysis is then used for making inferences about the effects of treatments, prognostic factors, exposures, and other covariates on the function.Immunoenzyme Techniques: Immunologic techniques based on the use of: (1) enzyme-antibody conjugates; (2) enzyme-antigen conjugates; (3) antienzyme antibody followed by its homologous enzyme; or (4) enzyme-antienzyme complexes. These are used histologically for visualizing or labeling tissue specimens.Mice, Transgenic: Laboratory mice that have been produced from a genetically manipulated EGG or EMBRYO, MAMMALIAN.Adenocarcinoma: A malignant epithelial tumor with a glandular organization.Dose-Response Relationship, Drug: The relationship between the dose of an administered drug and the response of the organism to the drug.Prognosis: A prediction of the probable outcome of a disease based on a individual's condition and the usual course of the disease as seen in similar situations.Neoplasm Grading: Methods which attempt to express in replicable terms the level of CELL DIFFERENTIATION in neoplasms as increasing ANAPLASIA correlates with the aggressiveness of the neoplasm.Retrospective Studies: Studies used to test etiologic hypotheses in which inferences about an exposure to putative causal factors are derived from data relating to characteristics of persons under study or to events or experiences in their past. The essential feature is that some of the persons under study have the disease or outcome of interest and their characteristics are compared with those of unaffected persons.Transfection: The uptake of naked or purified DNA by CELLS, usually meaning the process as it occurs in eukaryotic cells. It is analogous to bacterial transformation (TRANSFORMATION, BACTERIAL) and both are routinely employed in GENE TRANSFER TECHNIQUES.Base Sequence: The sequence of PURINES and PYRIMIDINES in nucleic acids and polynucleotides. It is also called nucleotide sequence.Cell Movement: The movement of cells from one location to another. Distinguish from CYTOKINESIS which is the process of dividing the CYTOPLASM of a cell.Craniopharyngioma: A benign pituitary-region neoplasm that originates from Rathke's pouch. The two major histologic and clinical subtypes are adamantinous (or classical) craniopharyngioma and papillary craniopharyngioma. The adamantinous form presents in children and adolescents as an expanding cystic lesion in the pituitary region. The cystic cavity is filled with a black viscous substance and histologically the tumor is composed of adamantinomatous epithelium and areas of calcification and necrosis. Papillary craniopharyngiomas occur in adults, and histologically feature a squamous epithelium with papillations. (From Joynt, Clinical Neurology, 1998, Ch14, p50)Survival Rate: The proportion of survivors in a group, e.g., of patients, studied and followed over a period, or the proportion of persons in a specified group alive at the beginning of a time interval who survive to the end of the interval. It is often studied using life table methods.Antibodies, Monoclonal: Antibodies produced by a single clone of cells.Cells, Cultured: Cells propagated in vitro in special media conducive to their growth. Cultured cells are used to study developmental, morphologic, metabolic, physiologic, and genetic processes, among others.Rhabdoid Tumor: A rare but highly lethal childhood tumor found almost exclusively in infants. Histopathologically, it resembles RHABDOMYOSARCOMA but the tumor cells are not of myogenic origin. Although it arises primarily in the kidney, it may be found in other parts of the body. The rhabdoid cytomorphology is believed to be the expression of a very primitive malignant cell. (From Holland et al., Cancer Medicine, 3d ed, p2210)Neuroectodermal Tumors: Malignant neoplasms arising in the neuroectoderm, the portion of the ectoderm of the early embryo that gives rise to the central and peripheral nervous systems, including some glial cells.Stereotaxic Techniques: Techniques used mostly during brain surgery which use a system of three-dimensional coordinates to locate the site to be operated on.Neurons: The basic cellular units of nervous tissue. Each neuron consists of a body, an axon, and dendrites. Their purpose is to receive, conduct, and transmit impulses in the NERVOUS SYSTEM.Cranial Irradiation: The exposure of the head to roentgen rays or other forms of radioactivity for therapeutic or preventive purposes.Genes, p53: Tumor suppressor genes located on the short arm of human chromosome 17 and coding for the phosphoprotein p53.Neurilemmoma: A neoplasm that arises from SCHWANN CELLS of the cranial, peripheral, and autonomic nerves. Clinically, these tumors may present as a cranial neuropathy, abdominal or soft tissue mass, intracranial lesion, or with spinal cord compression. Histologically, these tumors are encapsulated, highly vascular, and composed of a homogenous pattern of biphasic fusiform-shaped cells that may have a palisaded appearance. (From DeVita Jr et al., Cancer: Principles and Practice of Oncology, 5th ed, pp964-5)Gene Expression: The phenotypic manifestation of a gene or genes by the processes of GENETIC TRANSCRIPTION and GENETIC TRANSLATION.Image Processing, Computer-Assisted: A technique of inputting two-dimensional images into a computer and then enhancing or analyzing the imagery into a form that is more useful to the human observer.Neoplasm Staging: Methods which attempt to express in replicable terms the extent of the neoplasm in the patient.Gene Expression Profiling: The determination of the pattern of genes expressed at the level of GENETIC TRANSCRIPTION, under specific circumstances or in a specific cell.Gastrointestinal Stromal Tumors: All tumors in the GASTROINTESTINAL TRACT arising from mesenchymal cells (MESODERM) except those of smooth muscle cells (LEIOMYOMA) or Schwann cells (SCHWANNOMA).Radiopharmaceuticals: Compounds that are used in medicine as sources of radiation for radiotherapy and for diagnostic purposes. They have numerous uses in research and industry. (Martindale, The Extra Pharmacopoeia, 30th ed, p1161)Apoptosis: One of the mechanisms by which CELL DEATH occurs (compare with NECROSIS and AUTOPHAGOCYTOSIS). Apoptosis is the mechanism responsible for the physiological deletion of cells and appears to be intrinsically programmed. It is characterized by distinctive morphologic changes in the nucleus and cytoplasm, chromatin cleavage at regularly spaced sites, and the endonucleolytic cleavage of genomic DNA; (DNA FRAGMENTATION); at internucleosomal sites. This mode of cell death serves as a balance to mitosis in regulating the size of animal tissues and in mediating pathologic processes associated with tumor growth.Neoplasms, Neuroepithelial: Neoplasms composed of neuroepithelial cells, which have the capacity to differentiate into NEURONS, oligodendrocytes, and ASTROCYTES. The majority of craniospinal tumors are of neuroepithelial origin. (From Dev Biol 1998 Aug 1;200(1):1-5)Neoplasms, Radiation-Induced: Tumors, cancer or other neoplasms produced by exposure to ionizing or non-ionizing radiation.Polymerase Chain Reaction: In vitro method for producing large amounts of specific DNA or RNA fragments of defined length and sequence from small amounts of short oligonucleotide flanking sequences (primers). The essential steps include thermal denaturation of the double-stranded target molecules, annealing of the primers to their complementary sequences, and extension of the annealed primers by enzymatic synthesis with DNA polymerase. The reaction is efficient, specific, and extremely sensitive. Uses for the reaction include disease diagnosis, detection of difficult-to-isolate pathogens, mutation analysis, genetic testing, DNA sequencing, and analyzing evolutionary relationships.Rats, Nude: A mutant strain of Rattus norvegicus without a thymus and with depressed or absent T-cell function. This strain of rats may have a small amount of hair at times, but then lose it.Lomustine: An alkylating agent of value against both hematologic malignancies and solid tumors.Nerve Tissue ProteinsLoss of Heterozygosity: The loss of one allele at a specific locus, caused by a deletion mutation; or loss of a chromosome from a chromosome pair, resulting in abnormal HEMIZYGOSITY. It is detected when heterozygous markers for a locus appear monomorphic because one of the ALLELES was deleted.Sensitivity and Specificity: Binary classification measures to assess test results. Sensitivity or recall rate is the proportion of true positives. Specificity is the probability of correctly determining the absence of a condition. (From Last, Dictionary of Epidemiology, 2d ed)Optic Chiasm: The X-shaped structure formed by the meeting of the two optic nerves. At the optic chiasm the fibers from the medial part of each retina cross to project to the other side of the brain while the lateral retinal fibers continue on the same side. As a result each half of the brain receives information about the contralateral visual field from both eyes.Cerebral Cortex: The thin layer of GRAY MATTER on the surface of the CEREBRAL HEMISPHERES that develops from the TELENCEPHALON and folds into gyri and sulchi. It reaches its highest development in humans and is responsible for intellectual faculties and higher mental functions.Reproducibility of Results: The statistical reproducibility of measurements (often in a clinical context), including the testing of instrumentation or techniques to obtain reproducible results. The concept includes reproducibility of physiological measurements, which may be used to develop rules to assess probability or prognosis, or response to a stimulus; reproducibility of occurrence of a condition; and reproducibility of experimental results.Convection: Transmission of energy or mass by a medium involving movement of the medium itself. The circulatory movement that occurs in a fluid at a nonuniform temperature owing to the variation of its density and the action of gravity. (McGraw-Hill Dictionary of Scientific and Technical Terms, 4th ed; Webster, 10th ed)Kidney Neoplasms: Tumors or cancers of the KIDNEY.Chromosomes, Human, Pair 10: A specific pair of GROUP C CHROMOSOMES of the human chromosome classification.Ki-67 Antigen: A CELL CYCLE and tumor growth marker which can be readily detected using IMMUNOCYTOCHEMISTRY methods. Ki-67 is a nuclear antigen present only in the nuclei of cycling cells.PTEN Phosphohydrolase: A lipid phosphatase that acts on phosphatidylinositol-3,4,5-trisphosphate to regulate various SIGNAL TRANSDUCTION PATHWAYS. It modulates CELL GROWTH PROCESSES; CELL MIGRATION; and APOPTOSIS. Mutations in PTEN are associated with COWDEN DISEASE and PROTEUS SYNDROME as well as NEOPLASTIC CELL TRANSFORMATION.Flow Cytometry: Technique using an instrument system for making, processing, and displaying one or more measurements on individual cells obtained from a cell suspension. Cells are usually stained with one or more fluorescent dyes specific to cell components of interest, e.g., DNA, and fluorescence of each cell is measured as it rapidly transverses the excitation beam (laser or mercury arc lamp). Fluorescence provides a quantitative measure of various biochemical and biophysical properties of the cell, as well as a basis for cell sorting. Other measurable optical parameters include light absorption and light scattering, the latter being applicable to the measurement of cell size, shape, density, granularity, and stain uptake.Rats, Sprague-Dawley: A strain of albino rat used widely for experimental purposes because of its calmness and ease of handling. It was developed by the Sprague-Dawley Animal Company.Colonic Neoplasms: Tumors or cancer of the COLON.Pituitary Neoplasms: Neoplasms which arise from or metastasize to the PITUITARY GLAND. The majority of pituitary neoplasms are adenomas, which are divided into non-secreting and secreting forms. Hormone producing forms are further classified by the type of hormone they secrete. Pituitary adenomas may also be characterized by their staining properties (see ADENOMA, BASOPHIL; ADENOMA, ACIDOPHIL; and ADENOMA, CHROMOPHOBE). Pituitary tumors may compress adjacent structures, including the HYPOTHALAMUS, several CRANIAL NERVES, and the OPTIC CHIASM. Chiasmal compression may result in bitemporal HEMIANOPSIA.Skin Neoplasms: Tumors or cancer of the SKIN.Drug Delivery Systems: Systems for the delivery of drugs to target sites of pharmacological actions. Technologies employed include those concerning drug preparation, route of administration, site targeting, metabolism, and toxicity.Genetic Therapy: Techniques and strategies which include the use of coding sequences and other conventional or radical means to transform or modify cells for the purpose of treating or reversing disease conditions.Carcinoma, Ehrlich Tumor: A transplantable, poorly differentiated malignant tumor which appeared originally as a spontaneous breast carcinoma in a mouse. It grows in both solid and ascitic forms.Pinealoma: Neoplasms which originate from pineal parenchymal cells that tend to enlarge the gland and be locally invasive. The two major forms are pineocytoma and the more malignant pineoblastoma. Pineocytomas have moderate cellularity and tend to form rosette patterns. Pineoblastomas are highly cellular tumors containing small, poorly differentiated cells. These tumors occasionally seed the neuroaxis or cause obstructive HYDROCEPHALUS or Parinaud's syndrome. GERMINOMA; CARCINOMA, EMBRYONAL; GLIOMA; and other neoplasms may arise in the pineal region with germinoma being the most common pineal region tumor. (From DeVita et al., Cancer: Principles and Practice of Oncology, 5th ed, p2064; Adams et al., Principles of Neurology, 6th ed, p670)Liver Neoplasms: Tumors or cancer of the LIVER.Genes, Modifier: GENES with ALLELES that affect the PHENOTYPE associated with a nonallelic gene.Neuroblastoma: A common neoplasm of early childhood arising from neural crest cells in the sympathetic nervous system, and characterized by diverse clinical behavior, ranging from spontaneous remission to rapid metastatic progression and death. This tumor is the most common intraabdominal malignancy of childhood, but it may also arise from thorax, neck, or rarely occur in the central nervous system. Histologic features include uniform round cells with hyperchromatic nuclei arranged in nests and separated by fibrovascular septa. Neuroblastomas may be associated with the opsoclonus-myoclonus syndrome. (From DeVita et al., Cancer: Principles and Practice of Oncology, 5th ed, pp2099-2101; Curr Opin Oncol 1998 Jan;10(1):43-51)Fibrosarcoma: A sarcoma derived from deep fibrous tissue, characterized by bundles of immature proliferating fibroblasts with variable collagen formation, which tends to invade locally and metastasize by the bloodstream. (Stedman, 25th ed)Neoplasms, Multiple Primary: Two or more abnormal growths of tissue occurring simultaneously and presumed to be of separate origin. The neoplasms may be histologically the same or different, and may be found in the same or different sites.Magnetic Resonance Spectroscopy: Spectroscopic method of measuring the magnetic moment of elementary particles such as atomic nuclei, protons or electrons. It is employed in clinical applications such as NMR Tomography (MAGNETIC RESONANCE IMAGING).Cell Growth Processes: Processes required for CELL ENLARGEMENT and CELL PROLIFERATION.Amino Acid Sequence: The order of amino acids as they occur in a polypeptide chain. This is referred to as the primary structure of proteins. It is of fundamental importance in determining PROTEIN CONFORMATION.RNA, Neoplasm: RNA present in neoplastic tissue.Sarcoma, Experimental: Experimentally induced neoplasms of CONNECTIVE TISSUE in animals to provide a model for studying human SARCOMA.Follow-Up Studies: Studies in which individuals or populations are followed to assess the outcome of exposures, procedures, or effects of a characteristic, e.g., occurrence of disease.Biopsy: Removal and pathologic examination of specimens in the form of small pieces of tissue from the living body.Models, Biological: Theoretical representations that simulate the behavior or activity of biological processes or diseases. For disease models in living animals, DISEASE MODELS, ANIMAL is available. Biological models include the use of mathematical equations, computers, and other electronic equipment.Neurofibromatosis 1: An autosomal dominant inherited disorder (with a high frequency of spontaneous mutations) that features developmental changes in the nervous system, muscles, bones, and skin, most notably in tissue derived from the embryonic NEURAL CREST. Multiple hyperpigmented skin lesions and subcutaneous tumors are the hallmark of this disease. Peripheral and central nervous system neoplasms occur frequently, especially OPTIC NERVE GLIOMA and NEUROFIBROSARCOMA. NF1 is caused by mutations which inactivate the NF1 gene (GENES, NEUROFIBROMATOSIS 1) on chromosome 17q. The incidence of learning disabilities is also elevated in this condition. (From Adams et al., Principles of Neurology, 6th ed, pp1014-18) There is overlap of clinical features with NOONAN SYNDROME in a syndrome called neurofibromatosis-Noonan syndrome. Both the PTPN11 and NF1 gene products are involved in the SIGNAL TRANSDUCTION pathway of Ras (RAS PROTEINS).Up-Regulation: A positive regulatory effect on physiological processes at the molecular, cellular, or systemic level. At the molecular level, the major regulatory sites include membrane receptors, genes (GENE EXPRESSION REGULATION), mRNAs (RNA, MESSENGER), and proteins.Oligonucleotide Array Sequence Analysis: Hybridization of a nucleic acid sample to a very large set of OLIGONUCLEOTIDE PROBES, which have been attached individually in columns and rows to a solid support, to determine a BASE SEQUENCE, or to detect variations in a gene sequence, GENE EXPRESSION, or for GENE MAPPING.Fatal Outcome: Death resulting from the presence of a disease in an individual, as shown by a single case report or a limited number of patients. This should be differentiated from DEATH, the physiological cessation of life and from MORTALITY, an epidemiological or statistical concept.Case-Control Studies: Studies which start with the identification of persons with a disease of interest and a control (comparison, referent) group without the disease. The relationship of an attribute to the disease is examined by comparing diseased and non-diseased persons with regard to the frequency or levels of the attribute in each group.Ovarian Neoplasms: Tumors or cancer of the OVARY. These neoplasms can be benign or malignant. They are classified according to the tissue of origin, such as the surface EPITHELIUM, the stromal endocrine cells, and the totipotent GERM CELLS.Down-Regulation: A negative regulatory effect on physiological processes at the molecular, cellular, or systemic level. At the molecular level, the major regulatory sites include membrane receptors, genes (GENE EXPRESSION REGULATION), mRNAs (RNA, MESSENGER), and proteins.Boron Neutron Capture Therapy: A technique for the treatment of neoplasms, especially gliomas and melanomas in which boron-10, an isotope, is introduced into the target cells followed by irradiation with thermal neutrons.Radiotherapy: The use of IONIZING RADIATION to treat malignant NEOPLASMS and some benign conditions.Genes, Neurofibromatosis 1: Tumor suppressor genes located on the long arm of human chromosome 17 in the region 17q11.2. Mutation of these genes is thought to cause NEUROFIBROMATOSIS 1, Watson syndrome, and LEOPARD syndrome.Phosphorylation: The introduction of a phosphoryl group into a compound through the formation of an ester bond between the compound and a phosphorus moiety.Tumor Stem Cell Assay: A cytologic technique for measuring the functional capacity of tumor stem cells by assaying their activity. It is used primarily for the in vitro testing of antineoplastic agents.Cerebellum: The part of brain that lies behind the BRAIN STEM in the posterior base of skull (CRANIAL FOSSA, POSTERIOR). It is also known as the "little brain" with convolutions similar to those of CEREBRAL CORTEX, inner white matter, and deep cerebellar nuclei. Its function is to coordinate voluntary movements, maintain balance, and learn motor skills.Antineoplastic Combined Chemotherapy Protocols: The use of two or more chemicals simultaneously or sequentially in the drug therapy of neoplasms. The drugs need not be in the same dosage form.Proto-Oncogene Proteins: Products of proto-oncogenes. Normally they do not have oncogenic or transforming properties, but are involved in the regulation or differentiation of cell growth. They often have protein kinase activity.Promoter Regions, Genetic: DNA sequences which are recognized (directly or indirectly) and bound by a DNA-dependent RNA polymerase during the initiation of transcription. Highly conserved sequences within the promoter include the Pribnow box in bacteria and the TATA BOX in eukaryotes.Neuroma, Acoustic: A benign SCHWANNOMA of the eighth cranial nerve (VESTIBULOCOCHLEAR NERVE), mostly arising from the vestibular branch (VESTIBULAR NERVE) during the fifth or sixth decade of life. Clinical manifestations include HEARING LOSS; HEADACHE; VERTIGO; TINNITUS; and FACIAL PAIN. Bilateral acoustic neuromas are associated with NEUROFIBROMATOSIS 2. (From Adams et al., Principles of Neurology, 6th ed, p673)Phenotype: The outward appearance of the individual. It is the product of interactions between genes, and between the GENOTYPE and the environment.Carcinoma, Squamous Cell: A carcinoma derived from stratified SQUAMOUS EPITHELIAL CELLS. It may also occur in sites where glandular or columnar epithelium is normally present. (From Stedman, 25th ed)Mice, Knockout: Strains of mice in which certain GENES of their GENOMES have been disrupted, or "knocked-out". To produce knockouts, using RECOMBINANT DNA technology, the normal DNA sequence of the gene being studied is altered to prevent synthesis of a normal gene product. Cloned cells in which this DNA alteration is successful are then injected into mouse EMBRYOS to produce chimeric mice. The chimeric mice are then bred to yield a strain in which all the cells of the mouse contain the disrupted gene. Knockout mice are used as EXPERIMENTAL ANIMAL MODELS for diseases (DISEASE MODELS, ANIMAL) and to clarify the functions of the genes.RNA, Small Interfering: Small double-stranded, non-protein coding RNAs (21-31 nucleotides) involved in GENE SILENCING functions, especially RNA INTERFERENCE (RNAi). Endogenously, siRNAs are generated from dsRNAs (RNA, DOUBLE-STRANDED) by the same ribonuclease, Dicer, that generates miRNAs (MICRORNAS). The perfect match of the siRNAs' antisense strand to their target RNAs mediates RNAi by siRNA-guided RNA cleavage. siRNAs fall into different classes including trans-acting siRNA (tasiRNA), repeat-associated RNA (rasiRNA), small-scan RNA (scnRNA), and Piwi protein-interacting RNA (piRNA) and have different specific gene silencing functions.Immunotherapy: Manipulation of the host's immune system in treatment of disease. It includes both active and passive immunization as well as immunosuppressive therapy to prevent graft rejection.Melanoma, Experimental: Experimentally induced tumor that produces MELANIN in animals to provide a model for studying human MELANOMA.Pancreatic Neoplasms: Tumors or cancer of the PANCREAS. Depending on the types of ISLET CELLS present in the tumors, various hormones can be secreted: GLUCAGON from PANCREATIC ALPHA CELLS; INSULIN from PANCREATIC BETA CELLS; and SOMATOSTATIN from the SOMATOSTATIN-SECRETING CELLS. Most are malignant except the insulin-producing tumors (INSULINOMA).Choroid Plexus Neoplasms: Benign or malignant tumors which arise from the choroid plexus of the ventricles of the brain. Papillomas (see PAPILLOMA, CHOROID PLEXUS) and carcinomas are the most common histologic subtypes, and tend to seed throughout the ventricular and subarachnoid spaces. Clinical features include headaches, ataxia and alterations of consciousness, primarily resulting from associated HYDROCEPHALUS. (From Devita et al., Cancer: Principles and Practice of Oncology, 5th ed, p2072; J Neurosurg 1998 Mar;88(3):521-8)DNA-Binding Proteins: Proteins which bind to DNA. The family includes proteins which bind to both double- and single-stranded DNA and also includes specific DNA binding proteins in serum which can be used as markers for malignant diseases.Hypoxia, Brain: A reduction in brain oxygen supply due to ANOXEMIA (a reduced amount of oxygen being carried in the blood by HEMOGLOBIN), or to a restriction of the blood supply to the brain, or both. Severe hypoxia is referred to as anoxia, and is a relatively common cause of injury to the central nervous system. Prolonged brain anoxia may lead to BRAIN DEATH or a PERSISTENT VEGETATIVE STATE. Histologically, this condition is characterized by neuronal loss which is most prominent in the HIPPOCAMPUS; GLOBUS PALLIDUS; CEREBELLUM; and inferior olives.Angiogenesis Inhibitors: Agents and endogenous substances that antagonize or inhibit the development of new blood vessels.Electromagnetic Fields: Fields representing the joint interplay of electric and magnetic forces.Recombinant Proteins: Proteins prepared by recombinant DNA technology.Tomography, Emission-Computed: Tomography using radioactive emissions from injected RADIONUCLIDES and computer ALGORITHMS to reconstruct an image.Cell Cycle: The complex series of phenomena, occurring between the end of one CELL DIVISION and the end of the next, by which cellular material is duplicated and then divided between two daughter cells. The cell cycle includes INTERPHASE, which includes G0 PHASE; G1 PHASE; S PHASE; and G2 PHASE, and CELL DIVISION PHASE.Hydrocephalus: Excessive accumulation of cerebrospinal fluid within the cranium which may be associated with dilation of cerebral ventricles, INTRACRANIAL HYPERTENSION; HEADACHE; lethargy; URINARY INCONTINENCE; and ATAXIA.Cerebral Ventricle Neoplasms: Neoplasms located in the brain ventricles, including the two lateral, the third, and the fourth ventricle. Ventricular tumors may be primary (e.g., CHOROID PLEXUS NEOPLASMS and GLIOMA, SUBEPENDYMAL), metastasize from distant organs, or occur as extensions of locally invasive tumors from adjacent brain structures.Positron-Emission Tomography: An imaging technique using compounds labelled with short-lived positron-emitting radionuclides (such as carbon-11, nitrogen-13, oxygen-15 and fluorine-18) to measure cell metabolism. It has been useful in study of soft tissues such as CANCER; CARDIOVASCULAR SYSTEM; and brain. SINGLE-PHOTON EMISSION-COMPUTED TOMOGRAPHY is closely related to positron emission tomography, but uses isotopes with longer half-lives and resolution is lower.Granulosa Cell Tumor: A neoplasm composed entirely of GRANULOSA CELLS, occurring mostly in the OVARY. In the adult form, it may contain some THECA CELLS. This tumor often produces ESTRADIOL and INHIBIN. The excess estrogen exposure can lead to other malignancies in women and PRECOCIOUS PUBERTY in girls. In rare cases, granulosa cell tumors have been identified in the TESTES.Contrast Media: Substances used to allow enhanced visualization of tissues.Genetic Vectors: DNA molecules capable of autonomous replication within a host cell and into which other DNA sequences can be inserted and thus amplified. Many are derived from PLASMIDS; BACTERIOPHAGES; or VIRUSES. They are used for transporting foreign genes into recipient cells. Genetic vectors possess a functional replicator site and contain GENETIC MARKERS to facilitate their selective recognition.Membrane Proteins: Proteins which are found in membranes including cellular and intracellular membranes. They consist of two types, peripheral and integral proteins. They include most membrane-associated enzymes, antigenic proteins, transport proteins, and drug, hormone, and lectin receptors.DNA Methylation: Addition of methyl groups to DNA. DNA methyltransferases (DNA methylases) perform this reaction using S-ADENOSYLMETHIONINE as the methyl group donor.Hypothalamus, Anterior: The front portion of the HYPOTHALAMUS separated into the preoptic region and the supraoptic region. The preoptic region is made up of the periventricular GRAY MATTER of the rostral portion of the THIRD VENTRICLE and contains the preoptic ventricular nucleus and the medial preoptic nucleus. The supraoptic region contains the PARAVENTRICULAR HYPOTHALAMIC NUCLEUS, the SUPRAOPTIC NUCLEUS, the ANTERIOR HYPOTHALAMIC NUCLEUS, and the SUPRACHIASMATIC NUCLEUS.Transcription Factors: Endogenous substances, usually proteins, which are effective in the initiation, stimulation, or termination of the genetic transcription process.Necrosis: The pathological process occurring in cells that are dying from irreparable injuries. It is caused by the progressive, uncontrolled action of degradative ENZYMES, leading to MITOCHONDRIAL SWELLING, nuclear flocculation, and cell lysis. It is distinct it from APOPTOSIS, which is a normal, regulated cellular process.
Brain tumor. *PCNA. Astrocytoma. *Glial fibrillary acidic protein. NC/Melanoma. *S100 protein ... CD30, also known as TNFRSF8, is a cell membrane protein of the tumor necrosis factor receptor family and tumor marker. ... "Entrez Gene: TNFRSF8 tumor necrosis factor receptor superfamily, member 8".. *^ Teng LH, Lu DH, Xu QZ, Fu YJ, Yang H, He ZL ( ... tumor necrosis factor-activated receptor activity. • nerve growth factor binding. Cellular component. • cytoplasm. • integral ...
Brain tumor. *PCNA. Astrocytoma. *Glial fibrillary acidic protein. NC/Melanoma. *S100 protein ... 129 (Pt 6): 1353-6. doi:10.1093/brain/awl132. PMID 16738059.. *^ Metcalf P, Fusek M (April 1993). "Two crystal structures for ... Over-expression of cathepsin D stimulates tumorigenicity and metastasis as well as initiation of tumor apoptosis. This protease ... Ramirez-Montealegre D, Rothberg PG, Pearce DA (June 2006). "Another disorder finds its gene". Brain. ...
Brain tumor. *PCNA. Astrocytoma. *Glial fibrillary acidic protein. NC/Melanoma. *S100 protein ... Goldfarb LG, Vicart P, Goebel HH, Dalakas MC (April 2004). "Desmin myopathy". Brain. 127 (Pt 4): 723-34. doi:10.1093/brain/ ... desmin immunohistochemistry have a role in assessing stage of urothelial carcinoma in transurethral resection of bladder tumor ...
"Ultrastructure of capillary endothelium in pilocytic astrocytomas". Brain Tumor Pathol. 21 (1): 23-26. doi:10.1007/BF02482173 ...
Astrocytomas are brain tumors that develop from astrocytes. They may occur in many parts of the brain and sometimes in the ... Pilocytic astrocytoma are Grade I tumors. They are considered benign and slow growing tumors. Pilocytic astrocytomas frequently ... Astrocytomas are primary intracranial tumors derived from astrocytes cells of the brain. It is also possible that glial ... Anaplastic astrocytoma is classified as grade III and are malignant tumors. They grow more rapidly than lower grade tumors and ...
In February 2009, Barbero was diagnosed with Astrocytoma, an inoperable brain tumor. Even though he continued his PA announcing ...
Astrocytomas[edit]. Astrocytomas are primary intracranial tumors derived from astrocytes cells of the brain. It is also ... Astrocytomas are brain tumors that develop from astrocytes. They may occur in many parts of the brain and sometimes in the ... Pilocytic astrocytoma are Grade I tumors. They are considered benign and slow growing tumors. Pilocytic astrocytomas frequently ... a b c d Astrocytomas. International RadioSurgery Association (2010). *^ a b Astrocytoma Tumors. American Association of ...
It may lead to brain tumors such as astrocytomas. In some of the late-onset neurodegenerative diseases that share aggregation ... Gankyrin is anti-apoptotic and has been shown to be overexpressed in some tumor cell types such as hepatocellular carcinoma. In ... This approach of selectively inducing apoptosis in tumor cells has proven effective in animal models and human trials. ... Moreover, the UPS regulates the degradation of tumor suppressor gene products such as adenomatous polyposis coli (APC) in ...
In October 2016 Kadyrov was diagnosed - a brain tumor - astrocytoma of the third degree. He died in January 2017 . Судья КХЛ ...
In December 2015, Randa was diagnosed with a cancerous brain tumor, known as an astrocytoma. He died on September 5, 2016, aged ...
Donaldson was diagnosed with grade II astrocytoma, a type of malignant brain tumor. Despite radiation therapy, his long-term ... General of the State of California for the right to an elective cryopreservation to prevent the tumor from destroying his brain ... He said cryonics in some form would always be necessary because whether certain brain injuries were ultimately repairable would ... as long as the brain continues to exist in some kind of repairable form, "death" was merely a label indicating that the memory ...
May 1996). "Protein and messenger RNA expression of connexin43 in astrocytomas: implications in brain tumor gene therapy". J. ... Tumor suppressor genes (Cx43, Cx32 and Cx36). *Adhesive function independent of conductive gap junction channel (neural ... Connors; Long (2004). "Electrical synapses in the mammalian brain". Annu Rev Neurosci. 27: 393-418. doi:10.1146/annurev.neuro. ... December 1996). "Partial regression, yet incomplete eradication of mammary tumors in transgenic mice by retrovirally mediated ...
... of brain tumors. They can either start from normal brain cells or develop from an existing low-grade astrocytoma. The diagnosis ... Many drugs cannot cross the blood-brain barrier to act on the tumor. Treatment of primary brain tumors and brain metastases ... About 5% develop from another type brain tumor known as a low-grade astrocytoma. Uncommon risk factors include genetic ... Information about Glioblastoma Multiforme (GBM) from the American Brain Tumor Association AFIP Course Syllabus - Astrocytoma ...
The lesions include tumors of the brain or brainstem and arterio-venous malformations. Some of the tumors include astrocytoma, ... Cataplexy is considered secondary when it is due to specific lesions in the brain that cause a depletion of the hypocretin ... These lesions can be visualized with brain imaging, however in their early stages they can be missed. Other conditions in which ... The hypothalamus region of the brain regulates basic functions of hormone release, emotional expression and sleep. A study in ...
... s are a subset of brain tumors that present with an appearance of mixed glial cell origin, astrocytoma and ... Samantha Dickson Brain Tumour Trust: brain tumour research and support charity SDBTT Astro Fund, funding research and offering ... Survival time of this brain tumor varies - younger age and low-grade initial diagnosis are factors in improved survival time. ... Often called a "mixed glioma", about 2.3% of all reported brain tumors are diagnosed as oligoastrocytoma.[citation needed] The ...
It may lead to brain tumors such as astrocytomas.[95] In some of the late-onset neurodegenerative diseases that share ... Gankyrin is anti-apoptotic and has been shown to be overexpressed in some tumor cell types such as hepatocellular carcinoma.[81 ... Proteasome inhibitors have effective anti-tumor activity in cell culture, inducing apoptosis by disrupting the regulated ... and von Hippel-Lindau tumor suppressor (VHL), as well as a number of proto-oncogenes (Raf, Myc, Myb, Rel, Src, Mos, Abl). The ...
It is usually caused by a brain tumor such as a low-grade glioma or astrocytoma located in the hypothalamic-optic chiasmatic ...
... in brain tumors: an index of malignancy in astrocytomas". Int. J. Oncol. 22 (5): 1045-9. doi:10.3892/ijo.22.5.1045. PMID ...
It is mainly involved in diseases such as brain tumor and Down syndrome. OLIG2 is mostly expressed in restricted domains of the ... OLIG2 is universally expressed in glioblastoma and other diffuse gliomas (astrocytomas, oligodendrogliomas and ... OLIG2 is well recognized for its importance in cancer research, particularly in brain tumors and leukemia. ... and is a useful positive diagnostic marker of these brain tumors. In particular, OLIG2 is selectively expressed in a subgroup ...
Primary tumors[edit]. 1. Malignant Astrocytomas. Malignant astrocytomas are the most common primary brain tumors in adults. ... 1. Brain Tumor Presentations. In general, patients with primary brain tumors or single metastatic tumors can present with any ... including brain tumors. Prior cranial irradiation is the only risk factor that definitely predisposes to brain tumor formation ... Primary tumors of the central nervous system[edit]. Primary brain tumors can occur at any age, from infancy to late in life. ...
Recent studies suggest that some progesterone actions in astrocytoma cells (the most common and malignant human brain tumors) ... The presence of functional mPRα, mPRβ, and mPRγ subtypes were detected in both cell lines as well as in breast tumor tissues. ... Recently, it has also been discovered that mPRα and mPRβ are clearly expressed at mRNA and protein levels in astrocytoma cells ... Their roles in the process are unclear but it has been suggested that, at least, this steroid hormone may inhibit tumor ...
... astrocytoma, a brain tumor. The hex color #663399 was named "rebeccapurple" and added to the CSS color list in her memory. From ...
Everolimus was approved for treatment of TSC-related tumors in the brain (subependymal giant cell astrocytoma) in 2010 and in ... Three types of brain tumours may be associated with TSC: Giant cell astrocytoma: (grows and blocks the cerebrospinal fluid flow ... Tuberous sclerosis complex (TSC) is a rare multisystem genetic disease that causes benign tumors to grow in the brain and on ... Periungual fibromas: Also known as Koenen's tumors, these are small fleshy tumors that grow around and under the toenails or ...
Benign paroxysmal positional vertigo Brain tumors (medulloblastoma, astrocytoma, or other tumors in the posterior fossa.) ... doi:10.1093/brain/awh532. PMID 15872015. "Sensory Reception: Human Vision: Structure and function of the Human Eye" vol. 27, p ... These send signals to the nuclei for eye movement in the brain. From here, a signal is relayed to the extraocular muscles to ... Pierrot-Deseilligny C, Milea D (June 2005). "Vertical nystagmus: clinical facts and hypotheses". Brain. 128 (Pt 6): 1237-46. ...
The giant-cell glioblastoma is a rare neoplasia: its incidence is less than 1% of all brain tumors. It represents up to 5% of ... The age distribution includes children and has a wider range than other diffuse astrocytomas (diffuse WHO grade II astrocytoma ... ISBN 88-299-1739-7. [page needed] DeAngelis LM, Loeffler JS, Adam N. Mamelak AN (2007). "Primary and Metastatic Brain Tumors". ... page needed] Zulch KJ (1986). Brain Tumors: Their Biology and Pathology (3rd ed.). Berlin Heidelberg: Springer Verlag. ISBN 978 ...
... a potential target for novel medicines in malignant brain tumour therapies (mini-review)". Folia Neuropathologica. 45 (3): 99- ... Palma C, Manzini S (Jan 1998). "Substance P induces secretion of immunomodulatory cytokines by human astrocytoma cells". ... Donkin JJ, Turner RJ, Hassan I, Vink R (2007). "Substance P in traumatic brain injury". Progress in Brain Research. 161: 97-109 ... Substance P and the NK1 receptor are widely distributed in the brain and are found in brain regions that are specific to ...
... or choroid plexus tumor is a type of cancerous tumor that occurs in the brains choroid plexus tissue ... Condition Summary: Anaplastic Astrocytoma; Glioblastoma; Giant Cell Glioblastoma; Gliosarcoma; Anaplastic Oligodendroglioma; ... Additionally, there are support groups for people with brain tumors to assist you and your loved ones through this process. ... CSF circulates around the brain and spinal cord providing cushioning and protection. Because these tumors arise from the tissue ...
In this retrospective patient series, we report on 17 patients with primary brain tumors displaying a gliomatosis cerebri ... and seven diffuse astrocytomas). Patients have been treated with bevacizumab alone or in combination with lomustine or ... Due to the marked diffuse and infiltrative growth with less angiogenic tumor growth, it may appear questionable whether ... growth pattern (including seven glioblastomas, two anaplastic astrocytomas, one anaplastic oligodendroglioma, ...
Pediatric brain tumors account for approximately 25% of all cancers in children and are currently the leading cause of cancer- ... of the p53 tumor suppressor pathway and lack of egfr amplification distinguish de novo high grade pediatric astrocytomas from ... New approach to tumor therapy for inoperable areas of the brain: Chronic intraparenchymal drug delivery. J Neurooncol. 2002; 60 ... Owing to its aggressive nature, DIPG remains the primary cause of death from brain tumors diagnosed in children. As such, it ...
It is the most common primary neoplasm occurring the brain of dogs. ... Astrocytomas are brain tumors that affect the organs glial cells, which surround nerve cells (neurons), giving them support ... Astrocytoma in Dogs. Astrocytomas are brain tumors that affect the organs glial cells, which surround nerve cells (neurons), ... The astrocytomas biologic behavior depends on the tumors location and degree of lack of cell differentiation (graded I-IV, ...
... her father said they only had once chance to make the best decision about her brain tumor treatment. That led them to MD ... her father said they only had once chance to make the best decision about her brain tumor treatment. That led them to MD ... When Kellilyn Monar was diagnosed with an astrocytoma, ... When Kellilyn Monar was diagnosed with an astrocytoma, ... Simple seizure: an early brain tumor symptom. Kellilyn had learned she had a brain tumor two months earlier. She didnt know ...
Information about the survival rate for low grade and high grade astrocytomas. ... Order a free Brain Tumour Information Pack, to help you cope with a brain tumour diagnosis. ... Order a free Brain Tumour Information Pack, to help you cope with a brain tumour diagnosis. ... Our Brain Tumour Information Pack can help you better understand your diagnosis and feel confident talking to your medical team ...
... and radiation therapy in the treatment of newly diagnosed malignant astrocytomas. ... Brain Tumor News: Human interferon beta, nimustine hydrochloride, ... Home , Brain Tumor Guide , FAQs , Find A Treatment Noteworthy Treatments , News , Virtual Trial , Videos , Novocure Optune® , ... Donations , Brain Tumor Centers , Survivor Stories , Temodar®. Fundraising For Research , Unsubscribe , Contact Us Copyright (c ...
Results demonstrate that cerebellar and hypothalamo-chiasmatic pilocytic astrocytomas are two genetically distinct and ... Understanding the molecular basis responsible for the aggressive behaviour of hypothalamo-chiasmatic pilocytic astrocytomas is ... Pilocytic astrocytomas are WHO grade I gliomas that occur predominantly in childhood. They share features of both astroglial ... technique to compare the transcriptional profiles of five hypothalamo-chiasmatic and six cerebellar pilocytic astrocytomas. ...
Get information about types of astrocytoma brain tumour and their treatments, including pilocytic, diffuse and anaplastic ... Get your free brain tumour information pack. Our FREE Brain Tumour Information Pack has been designed to help you through this ... Order a free Brain Tumour Information Pack, to help you cope with a brain tumour diagnosis. ... Order a free Brain Tumour Information Pack, to help you cope with a brain tumour diagnosis. ...
Certain astrocytoma subtypes tend to occur in specific parts of the brain. Because astrocytes are a type of glial cell, ... astrocytomas are a specific type of glioma (tumors that arise from glial cells). In general, glial cells provide support to ... Astrocytomas, including glioblastomas, account for about 75.5% of all gliomas.1 ... These tumors can develop in various locations across the nervous system, including the cerebral hemispheres, cerebellum, and ...
键词: medicinal mushrooms, cancer, colon cancer, small cell lung carcinoma, lung adenocarcinoma, brain astrocytoma, human tumor ... and brain astrocytoma cancer cells. The obtained results suggest that due to the significant content of beneficial polyphenolic ... These results reveal that these extracts exhibit different cytotoxic effects on tumor cells originating from different tissues ... single mushroom compounds shows that blended mushroom extracts exhibit significantly stronger cytotoxic effects on human tumor ...
T1 - LASSO method in variable selection for right-censored time-to-event data with application to astrocytoma brain tumor and ... LASSO method in variable selection for right-censored time-to-event data with application to astrocytoma brain tumor and ... LASSO method in variable selection for right-censored time-to-event data with application to astrocytoma brain tumor and ... title = "LASSO method in variable selection for right-censored time-to-event data with application to astrocytoma brain tumor ...
Tumors can form in almost any type of tissue or cell in the brain or spinal cord. ... About 10% to 20% of brain tumors in children are brain stem gliomas. Nearly all of these tumors are some type of astrocytoma. ... These tumors start in brain glial cells called oligodendrocytes. These tumors tend to grow slowly, but like astrocytomas, most ... as opposed to primary brain tumors, which start in the brain). This is important because metastatic and primary brain tumors ...
This article explains the different types of childrens brain and spinal cord tumors and how they affect the body. ... Tumors can develop almost anywhere in a childs brain and spinal cord. ... They make up about 10-20% of all brain tumors in children. Astrocytomas often start in the pons. Thats a part of the brain ... Pilocytic astrocytomas are low-grade astrocytomas that are responsible for one in five brain tumors in children. They usually ...
It appears the tumor has reoccurred. He doesnt want... ... My youngest son has a recurring astrocytoma. He has undergone 2 ... Brain / CNS Tumors Support Group. A brain tumor is any intracranial tumor created by abnormal and uncontrolled cell division, ... metastatic tumors). Brain tumors may be benign or malignant. ... It appears the tumor has reoccurred. He doesnt want surgery ... normally either found in the brain itself, in the cranial nerves, in the brain envelopes, skull, pituitary and pineal gland, or ...
Learn about the different treatment options available for treating specific types of brain and spinal cancer tumors. Treatments ... Other spinal cord tumors are treated like those in the brain. Astrocytomas of the spinal cord usually cannot be removed ... Treating Specific Types of Adult Brain and Spinal Cord Tumors. The treatment options for brain and spinal cord tumors depend on ... Brain tumors that occur more often in children. Some types of brain tumors occur more often in children but do occur ...
Astrocytoma is type of brain tumor. This type of tumor begins from small, star-shaped cells called astrocytes. Astrocytes are ... Astrocytoma. (Brain Tumor; Glioma). by Michael Jubinville, MPH. • Definition • Causes • Risk Factors • Symptoms • Diagnosis • ... An astrocytoma is a type of the larger group of brain tumors called gliomas. ... Grade 3 tumors are called anaplastic astrocytomas. Grade 4 tumors are called glioblastoma multiforme (GBM). ...
... load TP53 trametinib tumor_classification tumor_evolution tumor_grading tumor_lysis_syndrome Tumor_Monorail tumor_mutational_ ... toxicity blood-brain_barrier boldine bortezomib boswellia brain_bleed brainstem_glioma BRCA2 budwig_diet butyrate BXQ-350 ... Tumour surgical resection. 18th feb 2016. tumour started to enhance in size. ... withania aspirin astragalus astrocytoma ATM_mutation atorvastatin ATRA_retinoic_acid atypical_glioma auranofin auras Australia ...
Recurrent Anaplastic Astrocytoma. Mixed Malignant Glioma. Oligodendroglioma. Irinotecan. Brain tumor. Nitrosoureas. Brain and ... Astrocytoma. Oligodendroglioma. Neoplasms, Neuroepithelial. Neuroectodermal Tumors. Neoplasms, Germ Cell and Embryonal. ... Astrocytoma Glioma Oligodendroglioma Drug: Irinotecan Hydrochloride (HCI) Treatment Drug: Continued Irinotecan Hydrochloride ( ... Also, a MRI (Cranial CT/MRI with and without contrast) was to be performed for tumor assessments at week 9, 18, 27, 36, and ...
... and anaplastic astrocytoma (AA), comprise the majority of all primary brain tumors in adults. This group of tumors also ... Patients with a histologically confirmed low grade brain tumor who relapse with an enhancing tumor on magnetic resonance ... tumors for treatment of increased intracranial pressure or symptomatic tumor edema. Patients with CNS tumors who are receiving ... Astrocytoma. Glioma. Neoplasms, Neuroepithelial. Neuroectodermal Tumors. Neoplasms, Germ Cell and Embryonal. Neoplasms by ...
I Am a Brain Tumor Survivor. My mother had a brain tumor. 2 doctors both from different hospital told me my mom had 6 months to ... More From People Who Are Brain Tumor Survivors Astrocytoma In 1972 I was 14 years old. By the time I got a correct diagnosis, ... When I was 12 years old, I had a brain tumor that was cancerous. The doctors didnt think i would live or if I did would not be ... My mother had a brain tumor. 2 doctors both from different hospital told me my mom had 6 months to live and if i decided to ...
Pediatric brain tumor, Pyrosequencing, Secondary anaplastic astrocytoma",. author = "Samantha Mascelli and Alessandro Raso and ... Most noteworthy, the IDH1 mutant tumor was an anaplastic astrocytoma involving the cortex in the left frontal lobe which ... Most noteworthy, the IDH1 mutant tumor was an anaplastic astrocytoma involving the cortex in the left frontal lobe which ... Most noteworthy, the IDH1 mutant tumor was an anaplastic astrocytoma involving the cortex in the left frontal lobe which ...
Brain Tumour Survivor. A site dedicated to leading edge treatment for brain tumours. ... Hi wondering if anyone else has a brain stem tumour that is benign and has had radiation. Did it work? Due to location (6th/7th ... Hi wondering if anyone else has a brain stem tumour that is benign and has had radiation. Did it work? Due to location (6th/7th ... He said that he would eventually become quadriplegic and the brain stem tumor would stop his breathing and heart beat. His ...
rCBV and Astrocytoma Grading.. Gliomas are the most common primary tumors of the brain, with astrocytomas being the most common ... rCBV and Tumor-Mimicking Brain Lesions.. Numerous lesions of the brain can simulate brain tumor on anatomic images, such as ... For example, pilocytic astrocytomas, a common pediatric brain tumor and a WHO grade I astrocytoma, often demonstrate vascular ... rCBV and Brain Tumors Other Than Gliomas.. Meningiomas are the second-most-common primary tumors of the brain. The most common ...
Cook Childrens is among the nations finest when it comes to treating brain tumors. And we have access to some of the newest ... Astrocytomas originate from star-shaped brain cells known as astrocytes. There are four major subtypes of astrocytomas:. * ... What is a brain tumor?. A tumor is any mass caused by abnormal or uncontrolled growth of cells. Tumors in the brain are ... What causes a brain tumor?. Like all tumors, brain tumors originate when a normal cell begins to grow abnormally and multiply ...
  • Due to the marked diffuse and infiltrative growth with less angiogenic tumor growth, it may appear questionable whether bevacizumab can have a therapeutic effect in those patients. (lns.lu)
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