• Considering the different effects of ambra1a and ambra1b on sexual differentiation, we decided to investigate the role of Ambra1 in this process. (biomedcentral.com)
  • Although most developmental changes occur during the embryonic and fetal periods, important changes occur during later periods of development: infancy, childhood, adolescence, and early adulthood Development does not stop at birth. (pickpdfs.com)
  • During the fetal period, differentiation and growth of tissues and organs occur. (pickpdfs.com)
  • However, the comprehensive chromatin state has not yet been analyzed for human fetal germ cells (FGCs). (nature.com)
  • Here we use nucleosome occupancy and methylation sequencing method to analyze both the genome-wide chromatin accessibility and DNA methylome at a series of crucial time points during fetal germ cell development in both human and mouse. (nature.com)
  • The best evidence suggests that most are due to abnormal differentiation of fetal germ cells that arise from the fetal yolk sac. (medscape.com)
  • We determined the expression of components of the ECS in the human fetal testis from 6 to 17 developmental weeks and assessed the direct effects of phytocannabinoids Δ9-trans-tetrahydrocannabinol (THC) and cannabidiol (CBD) on the testis morphology and cell functions ex vivo. (biomedcentral.com)
  • We demonstrated that the silencing of the ambra1b gene determines a reduction of primordial germ cells (PGCs), a condition that, in the zebrafish, leads to the development of all-male progeny. (biomedcentral.com)
  • This discovery invalidated the "fixation theory of primordial follicle pool" and suggested for the first time the hypothesis that germ stem cells also exist in the ovary. (biomedcentral.com)
  • Depending on the species, DAZL is expressed in primordial germ cells (PGCs) and/or pre-meiotic and meiotic germ cells of both sexes. (ijbs.com)
  • Where the spermatozoa begin to be produced starting from the germ cells that are primordial to the male. (cassiopaea-cult.com)
  • Chromatin remodeling is important for the epigenetic reprogramming of human primordial germ cells. (nature.com)
  • Niikura [ 5 ] and others observed germ cells expressing Stra8 (stimulated by retinoic acid gene 8) in the ovarian surface epithelium, indicating that there may be germ cells with meiotic function in the ovary. (biomedcentral.com)
  • Genetic recombination occurs when the chromosomes pair throughout meiotic prophase and the chromosomes pass over, resulting in genetic variety. (themagazinenews.com)
  • Then, typically, genes for transcription factors, are delivered by viral vectors into the cell nuclei, where they are incorporated into the genome. (jove.com)
  • The transcription factors then turn on genes that are expressed by embryonic stem cells. (jove.com)
  • Then, genes for multiple transcription factors are delivered into the cells using a viral vector, and the transcription factor proteins are expressed using the cell's machinery. (jove.com)
  • The transcription factors then turn on many other genes that are expressed by embryonic stem cells, returning the cells to an undifferentiated, proliferative, and pluripotent state. (jove.com)
  • Defects in the chromosomes occur, and they reunite, swapping some genes. (themagazinenews.com)
  • The expression of cyclin-dependent kinase inhibitors was profoundly affected with early activation and then repression of p21 cip1/waf1 and persistent activation of both p27 kip1 and p57 kip2 , whereas genes involved in cell survival and proliferation were suppressed. (aacrjournals.org)
  • Moreover, we find that the distal NDRs are enriched specifically for binding motifs of the pluripotency and germ cell master regulators such as NANOG, SOX17, AP2γ and OCT4 in human FGCs, indicating the existence of a delicate regulatory balance between pluripotency-related genes and germ cell-specific genes in human FGCs, and the functional significance of these genes for germ cell development in vivo . (nature.com)
  • Mutter suggested that these genes or the cells have only the maternal imprint because many teratomas arise from a parthenogenetically activated egg. (medscape.com)
  • The resultant cells after fission carry equal number of chromosomes and genes. (brainyhomeworkhelp.com)
  • Using the Drosophila nephrocyte as a genetic screen platform, most genes involved in endocytosis and cell trafficking were screened, and the key components were identified of the cell trafficking pathway required for SD protein endocytosis and recycling. (sdbonline.org)
  • Genes are contained in chromosomes in the cell nucleus and mitochondria. (msdmanuals.com)
  • the smaller Y chromosome carries genes that initiate male sex differentiation, as well as a few other genes. (msdmanuals.com)
  • Some genes occur in multiple copies that may be next to each other or in different locations in the same or different chromosomes. (msdmanuals.com)
  • explosion further, consider that a fictitious small genome with 2002) More recently and more dramatically, the potential for 260 genes would host the same number of combinations as cell state conversions is exemplified by the reprogramming of the number of atoms in the visible universe! (lu.se)
  • Dazl can regulate the expression, transport and localization of target mRNAs of proteins which control the differentiation, growth and maturation of germ cells. (ijbs.com)
  • CD40 ligand is also necessary for T cells to interact with other cells of the immune system, and it plays a key role in the maturation (differentiation) of T cells, which allows them to carry out their specific functions. (medlineplus.gov)
  • The ovarian microenvironment affects the proliferation and differentiation of OGSCs, and immune cells and related cytokines are important components of the microenvironment. (biomedcentral.com)
  • With increasing time, the fluorescence intensity of cells gradually increased, and the cytokines IL-2 and TNF-α significantly promoted the proliferation of OGSCs. (biomedcentral.com)
  • It was found that ovoid cells in the epithelial layer of the ovary simultaneously expressed the germ cell specific marker MVH and the proliferation of cell marker BrdU using double-immunofluorescence staining. (biomedcentral.com)
  • It is worth noting that the proliferation and differentiation of stem cells cannot be separated from the surrounding microenvironment, and immune system related cells are an important part of the microenvironment of the OGSCs nest [ 14 ]. (biomedcentral.com)
  • Ex vivo exposure of first trimester testes to CBD, THC, or CBD/THC [ratio 1:1] at 10 −7 to 10 −5 M altered testosterone secretion by Leydig cells, AMH secretion by Sertoli cells, and impacted testicular cell proliferation and viability as early as 72 h post-exposure. (biomedcentral.com)
  • The proliferation and differentiation of adult stem cells must be tightly balanced to avoid excessive proliferation or premature differentiation. (sdbonline.org)
  • However, how stem cell proliferation is properly controlled remains elusive. (sdbonline.org)
  • This study found that auxilin (Aux) restricts intestinal stem cell (ISC) proliferation mainly through EGFR signaling. (sdbonline.org)
  • Malrotation occurs in the setting of developmental anomalies, in which the intestine fails to return to the nascent abdominal cavity, such as congenital diaphragmatic hernia as well as abdominal wall defects. (medscape.com)
  • DAZ family proteins are located in the nucleus and/or in the cytoplasm of male and female germ cells at different developmental stages throughout the gametogenesis. (ijbs.com)
  • The main developmental changes occurring before birth are illustrated in the Timetable of Human Prenatal Development (Figs. 1-1 and 1-2). (pickpdfs.com)
  • In this Review, we briefly outline the roles that follicle-stimulating hormone (FSH) and testosterone play in regulating spermatogenesis and describe our current understanding of how vitamin A regulates germ cell differentiation and how it may lead to the generation of both the cycle of the seminiferous epithelium and the spermatogenic wave. (jci.org)
  • Recombination and separation of homologous chromosomes occurs in pachytene spermatocytes during meiosis I and results in the formation of secondary spermatocytes. (jci.org)
  • At the equator of the cell, bivalent chromosomes connect to the spindles and realign. (themagazinenews.com)
  • During meiosis, a zygote will have twenty-three chromosomes, but cell differentiation implies that each gamete will have one of many distinct ideas are based. (themagazinenews.com)
  • When we talk about human cells we have 46 chromosomes, with the exception of gametes. (cassiopaea-cult.com)
  • Which in turn will separate into two cells each with 23 chromosomes, which are the haploid spermatids. (cassiopaea-cult.com)
  • In females (who have two X chromosomes), a variant would have to occur in both copies of the gene to cause the disorder. (medlineplus.gov)
  • In humans, somatic (nongerm) cell nuclei normally have 46 chromosomes in 23 pairs. (msdmanuals.com)
  • A karyotype illustrates the full set of chromosomes in a person's cells. (msdmanuals.com)
  • Germ cells (egg and sperm) divide through meiosis, which reduces the number of chromosomes to 23-half the number in somatic cells. (msdmanuals.com)
  • DNA (deoxyribonucleic acid) is the cell's genetic material, contained in chromosomes within the cell nucleus and mitochondria. (msdmanuals.com)
  • Except for certain cells (for example, sperm and egg cells and red blood cells), the cell nucleus contains 23 pairs of chromosomes. (msdmanuals.com)
  • Stromal tumors of the ovary include germ-cell tumors, sex-cord stromal tumors, and other more rare types. (medscape.com)
  • We also molecularly defined the development of Sertoli, Leydig and peritubular myoid cells during the perinatal period, allowing us to identify candidate signaling pathways acting between somatic and germ cells in a stage-specific manner during the perinatal period. (biologists.com)
  • [7] The complex cell signaling pathways of multicellular organisms such as plants and humans can make understanding the mechanisms of this inherited process very difficult. (cloudfront.net)
  • In terminally differentiated cell fate is coupled to appropriate regulation of the alternative cells, transcriptional networks must be stable and irreversible, pathways. (lu.se)
  • Using single-cell RNA sequencing (RNAseq), we studied the development of ProSG, their SG descendants and testicular somatic cells during the perinatal period in mice. (biologists.com)
  • Undifferentiated spermatogonia divide mitotically to both repopulate the testicular stem cell population and provide progenitor cells that undergo spermatogenesis. (jci.org)
  • In the two-day span, cells undergo transformation to develop a fertilized egg called zygote. (brainyhomeworkhelp.com)
  • The female germ or sex cells are produced in the ovaries. (pickpdfs.com)
  • Interestingly, ovaries occur more commonly on the left side than the right. (medscape.com)
  • DNA is wrapped into a DNA-protein complex called chromatin in the nucleus of eukaryotic cells. (cloudfront.net)
  • Although the genome-wide histone modification landscapes of mouse in vivo germ cells and in vitro PGCLCs have been profiled and several germline-specific properties of epigenetic reprogramming have been revealed, the study of genome-scale chromatin states in human FGCs is still challenging, due to the scarcity of materials and technical difficulties. (nature.com)
  • Mechanochemical Principles of Spatial and Temporal Patterns in Cells and Tissues. (mpi-cbg.de)
  • Patterns are ubiquitous in living systems and underlie the dynamic organization of cells, tissues, and embryos. (mpi-cbg.de)
  • This is called autologous transplantation, and it reduces the risk of transplant rejection that can occur when tissues are transplanted between individuals. (jove.com)
  • Early progenitor cells, which are designated A spermatogonia in the mouse and A- dark spermatogonia in humans, are defined as "undifferentiated. (jci.org)
  • To varying degrees, these fates also extend to the Such state stability is required in stem and progenitor cells to immediate progeny of stem cells, known as progenitor or support self-renewal and maintenance of the uncommitted transit-amplifying cells. (lu.se)
  • Depending on the molecules and testis age, highly deleterious effects of phytocannabinoid exposure were observed on testis tissue after 14 days, including Sertoli and germ cell death. (biomedcentral.com)
  • It is difficult to determine exactly when fertilization (conception) occurs because the process cannot be observed in vivo (within the living body). (pickpdfs.com)
  • which would be the male reproductive cell, the gamete, destined to the fertilization of the ovum. (cassiopaea-cult.com)
  • HN - 2008 BX - Von Ebner's Glands MH - Cumulus Cells UI - D054885 MN - A05.360.319.114.630.535.200.500 MN - A06.407.312.497.535.300.500 MN - A11.436.300.500 MS - The granulosa cells of the cumulus oophorus which surround the OVUM in the GRAAFIAN FOLLICLE. (bvsalud.org)
  • However, it remains unknown whether inactivation of EBF3 locus also occurs in other types of tumors and what functions of EBF3 underlie EBF3-mediated tumor suppression. (aacrjournals.org)
  • Teratomas (from Greek teras, meaning "monster," and - oma, a suffix denoting a tumor or neoplasm) and other germ cell tumors are relatively common solid neoplasms in children. (medscape.com)
  • These tumors are grouped together because they all appear to arise from postmeiotic germ cells. (medscape.com)
  • Normal migration of these germ cells may cause gonadal tumors, whereas abnormal migration produces extragonadal tumors. (medscape.com)
  • In 1965, Teilum first suggested the germ cell origin of gonadal tumors. (medscape.com)
  • Other recent studies verified the presence of PAPP-A mRNA in granulosa cells of humans, monkeys, cattle, mice, and pigs. (bioone.org)
  • Increases in the amount of PAPP-A mRNA in granulosa cells during follicular development occurs in some but not all species, indicating that other proteases or protease inhibitors may be involved in IGFBP degradation. (bioone.org)
  • The localization of DAZ family proteins suggests that they can regulate mRNA translation occurring in the cytoplasm. (ijbs.com)
  • DAZ family proteins are found almost exclusively in germ cells in distant animal species. (ijbs.com)
  • In the cleavage process, cells are united together by adhesive proteins, which must be deactivated to permit movements of specific cells. (brainyhomeworkhelp.com)
  • This is followed by a process known as cavitation in which the outer cells secret fluid containing proteins into the sphere, facilitating rapid division of the cells (Forgacs & Newman, 2005). (brainyhomeworkhelp.com)
  • Disrupting any component in this pathway led to disrupted SD on the cell surface and intracellular accumulation of mislocalized SD proteins. (sdbonline.org)
  • Leydig cell hyperplasia may also occur with aging. (medscape.com)
  • Laterally, the mesoderm undergoes differentiation: para-axial (peripheral nervous system), intermediate (gonads and kidneys), and lateral, which further divides into splanchnic (gastrointestinal [GI] tract) and somatic (body wall). (medscape.com)
  • The structure, regulation, and cell types of the mouse testis. (jci.org)
  • In order for epigenetic marks to be heritable, however, they must occur in the gametes in animals, but since plants lack a definitive germline and can propagate, epigenetic marks in any tissue can be heritable. (cloudfront.net)
  • X-linked hyper IgM syndrome is a condition that affects the immune system and occurs almost exclusively in males. (medlineplus.gov)
  • Induced Pluripotent Stem Cell Lines Derived from Human Somatic Cells' (2007), by Junying Yu et al. (asu.edu)
  • On 2 December 2007, Science published a report on creating human induced pluripotent stem (iPS) cells from human somatic cells: "Induced Pluripotent Stem Cell Lines Derived from Human Somatic Cells. (asu.edu)
  • So when I was recently contacted by an earnest and amiable member of a local school board who was concerned about the questionable manner in which the issue of "stem cell" research - both human embryonic and adult - was presented to the high school students in his district in a currently-used science textbook, I agreed to evaluate that section in the text for him. (lifeissues.net)
  • My edited analysis of the section on "stem cell research" in this science textbook is copied below. (lifeissues.net)
  • In my opinion there is no question but that the scientific information on stem cell research included in this science text book being used in Illinois schools incorporates some inaccurate scientific facts, and seems to be very partial to the use of human embryonic "stem cell" research. (lifeissues.net)
  • Stem Cell Reports 17(5): 1120-1137. (sdbonline.org)
  • Understanding cell-fate decisions in stem cell populations is a major goal of modern biology. (lu.se)
  • Stem and progenitor cell populations are often heterogeneous, which may reflect stem cell subsets that express subtly different properties, including different propensities for lineage selection upon differentiation, yet remain able to interconvert. (lu.se)
  • We discuss these properties with examples both from the hematopoietic and embryonic stem cell (ESC) systems. (lu.se)
  • The nature of the stem cell substates and their relationship to commitment to differ- entiate and lineage selection can be elucidated in terms of a landscape picture in which stable states can be defined mathematically as attractors. (lu.se)
  • We identified both gene and protein markers for three temporally distinct ProSG cell subsets, including a migratory cell population with a transcriptome distinct from the previously defined T1- and T2-ProSG stages. (biologists.com)
  • This gene provides instructions for making a protein called CD40 ligand, which is found on the surface of immune system cells known as T cells. (medlineplus.gov)
  • Variants in the CD40LG gene also impair the T cell's ability to mature and interact with other immune system cells. (medlineplus.gov)
  • In males (who have only one X chromosome), one altered copy of the gene in each cell is sufficient to cause the condition. (medlineplus.gov)
  • Similarly, GATA-1 has been shown to induce lineage switching expression values even if, for simplicity, we assume only ``on'' of committed cells in hematopoiesis, first in cell lines (Kulessa and ``off'' states for each gene. (lu.se)
  • In reality, gene somatic cells to a pluripotent cell state by a handful of transcrip- expression is graded, making the potential gene expression tion factors (Takahashi and Yamanaka, 2006). (lu.se)
  • HN - 2008 BX - Granulosa Cells, Cumulus MH - Coronary Sinus UI - D054326 MN - A07.231.908.194.500 MS - A short vein that collects about two thirds of the venous blood from the MYOCARDIUM and drains into the RIGHT ATRIUM. (bvsalud.org)
  • Silencing of the EBF3 locus was observed in brain, colorectal, breast, liver, and bone tumor cell lines and its reactivation was achieved on treatment with 5-aza-2′-deoxycytidine and trichostatin A in a significant portion of these tumor cells. (aacrjournals.org)
  • If hypogonadism occurs before puberty , puberty does not progress. (encyclopedia.com)
  • If hypogonadism occurs after puberty, infertility and sexual dysfunction result. (encyclopedia.com)
  • After birth, sexual development does not occur until puberty. (encyclopedia.com)
  • In all documented biopsied cases, there is a significant decline in germ cell development and an increase in tubular sclerosis by puberty. (medscape.com)
  • This is the series of mitotic cell divisions of the zygote that result in the formation of early embryonic cells, blastomeres. (pickpdfs.com)
  • The zygote formed after fertilization divides into multiple cells through a process known as binary fission (Campbell & Reece, 2005). (brainyhomeworkhelp.com)
  • Despite the increase in the number of cells in this phase, the volume of the zygote remains the same. (brainyhomeworkhelp.com)
  • The morula stage occurs 3 to 4 days after fertilization, just as the early embryo enters the uterus. (pickpdfs.com)
  • Further divisions within the sphere lead to the formation of a 32-cell mass known as morula. (brainyhomeworkhelp.com)
  • Further development of the morula leads to formation of a ball containing about 2000 cells known as blastocyst. (brainyhomeworkhelp.com)
  • These cells have the potential to become gametes but have not yet committed to the process. (jci.org)
  • If you were to implant this embryonic tooth germ into a patient, the idea goes, it would begin to communicate with the surrounding tissue, thus releasing the entire cascade of messengers and initiating the process of tooth development. (bionity.com)
  • Important changes, in addition to growth, occur after birth (e.g., development of teeth and female breasts). (pickpdfs.com)
  • Prenatal development is the process that occurs during pregnancy whereby an embryo gestates from fertilization to birth. (brainyhomeworkhelp.com)
  • Evidence the fate of stem cells has broad ramifications for biomedical suggests that during development or differentiation, cells make science from elucidating the causes of cancer to the use of very precise transitions between apparently stable ``network stem cells in regenerative medicine. (lu.se)
  • As a result of this condensation, the embryonic tooth germ begins to interact with surrounding cell layers in the jaw via specific messengers. (bionity.com)
  • Epiblast cells pour into the primitive node, converting the bilaminar disc into a disk with three germ cell layers. (medscape.com)
  • It is still being studied whether iPSCs are truly equivalent to embryonic stem cells, but they appear to be similar and can produce cells from all three germ layers of the body. (jove.com)
  • These abnormalities may account for the lack of organization of the three germ cell layers. (medscape.com)
  • The relaxed cellular bonds allow the inner cell mass to enlarge and reorganize into specific layers. (brainyhomeworkhelp.com)
  • One the layers, the epiblast, is layer of cells, which are the precursors of all embryonic cells. (brainyhomeworkhelp.com)
  • and the unique differentiation of haploid cells (spermiogenesis) (Figure 1 ). (jci.org)
  • That is, they divide and are pluripotent, able to produce any cell type in the body. (jove.com)
  • The cells can now divide, and ideally, be directed to produce a specific cell type in culture. (jove.com)
  • Stem cells are undifferentiated cells that divide and produce different types of cells. (jove.com)
  • Ordinarily, cells that have differentiated into a specific cell type are post-mitotic-that is, they no longer divide. (jove.com)
  • This requirement strongly limits the number of solutions or entiation and lineage-specification, programmed cell death, and ``states'' for the system. (lu.se)
  • Invagination occurs along the primitive streak, giving the embryo (in cross-section) the appearance of an omega. (medscape.com)
  • Female is the default sex of the embryo, so most of the sex organ deficits at birth occur in boys. (encyclopedia.com)
  • The coordinated cell movements result in a spatially organized embryo, and puts together the framework on which other features are to develop from into building the body. (brainyhomeworkhelp.com)
  • However, it contains a thick inner layer of cells at one end of the inner cavity, from which the embryo will develop (Campbell & Reece, 2005). (brainyhomeworkhelp.com)
  • To create iPSCs, mature cells, like skin fibroblasts, are taken from a patient and put into culture. (jove.com)
  • To create iPSCs, mature cells such as skin fibroblasts or blood cells from a person are grown in culture. (jove.com)
  • 2008). Historically, this concept is highlighted by the experi- factors are key intrinsic regulators of these fate decisions and mental phenomenon of lineage reprogramming, for example, that fate choice involves modulating networks of transcription by the conversion of fibroblasts to muscles cells following trans- factors. (lu.se)