A genus of gram-positive, aerobic bacteria. Most species are free-living in soil and water, but the major habitat for some is the diseased tissue of warm-blooded hosts.

A species of gram-positive, aerobic bacteria that produces TUBERCULOSIS in humans, other primates, CATTLE; DOGS; and some other animals which have contact with humans. Growth tends to be in serpentine, cordlike masses in which the bacilli show a parallel orientation.

Infections with bacteria of the genus MYCOBACTERIUM.

The bovine variety of the tubercle bacillus. It is called also Mycobacterium tuberculosis var. bovis.

A bacterium causing tuberculosis in domestic fowl and other birds. In pigs, it may cause localized and sometimes disseminated disease. The organism occurs occasionally in sheep and cattle. It should be distinguished from the M. avium complex, which infects primarily humans.

A rapid-growing, nonphotochromogenic species of MYCOBACTERIUM originally isolated from human smegma and found also in soil and water. (From Dorland, 28th ed)

So-called atypical species of the genus MYCOBACTERIUM that do not cause tuberculosis. They are also called tuberculoid bacilli, i.e.: M. buruli, M. chelonae, M. duvalii, M. flavescens, M. fortuitum, M. gilvum, M. gordonae, M. intracellulare (see MYCOBACTERIUM AVIUM COMPLEX;), M. kansasii, M. marinum, M. obuense, M. scrofulaceum, M. szulgai, M. terrae, M. ulcerans, M. xenopi.

A species of gram-positive, aerobic bacteria that causes LEPROSY in man. Its organisms are generally arranged in clumps, rounded masses, or in groups of bacilli side by side.

A complex that includes several strains of M. avium. M. intracellulare is not easily distinguished from M. avium and therefore is included in the complex. These organisms are most frequently found in pulmonary secretions from persons with a tuberculous-like mycobacteriosis. Strains of this complex have also been associated with childhood lymphadenitis and AIDS; M. avium alone causes tuberculosis in a variety of birds and other animals, including pigs.

Infections with nontuberculous mycobacteria (atypical mycobacteria): M. kansasii, M. marinum, M. scrofulaceum, M. flavescens, M. gordonae, M. obuense, M. gilvum, M. duvali, M. szulgai, M. intracellulare (see MYCOBACTERIUM AVIUM COMPLEX;), M. xenopi (littorale), M. ulcerans, M. buruli, M. terrae, M. fortuitum (minetti, giae), M. chelonae.

A rapid-growing, nonphotochromogenic species that is potentially pathogenic, producing lesions of lung, bone, or soft tissue following trauma. It has been found in soil and in injection sites of humans, cattle, and cold-blooded animals. (Dorland, 28th ed)

A moderate-growing, photochromogenic species found in aquariums, diseased fish, and swimming pools. It is the cause of cutaneous lesions and granulomas (swimming pool granuloma) in humans. (Dorland, 28th ed)

A species of gram-positive, aerobic bacteria commonly found in soil and occasionally isolated from sputum. It causes postoperative wound infections as well as gluteal abscesses.

A subspecies of gram-positive, aerobic bacteria. It is the etiologic agent of Johne's disease (PARATUBERCULOSIS), a chronic GASTROENTERITIS in RUMINANTS.

Any of the infectious diseases of man and other animals caused by species of MYCOBACTERIUM.

A slow-growing, photochromogenic species that is the etiologic agent of a tuberculosis-like disease in humans and is frequently isolated from human pulmonary secretions or tubercles. The incidence of infection is sharply increased among immunocompromised individuals. (Dorland, 28th ed)

A nontuberculous infection when occurring in humans. It is characterized by pulmonary disease, lymphadenitis in children, and systemic disease in AIDS patients. Mycobacterium avium-intracellulare infection of birds and swine results in tuberculosis.

A slow-growing mycobacterium that infects the skin and subcutaneous tissues, giving rise to indolent BURULI ULCER.

A saprophytic bacterium widely distributed in soil and dust and on plants.

Drugs used in the treatment of tuberculosis. They are divided into two main classes: "first-line" agents, those with the greatest efficacy and acceptable degrees of toxicity used successfully in the great majority of cases; and "second-line" drugs used in drug-resistant cases or those in which some other patient-related condition has compromised the effectiveness of primary therapy.

MYCOBACTERIUM infections of the lung.

Proteins found in any species of bacterium.

Mycolic acids are complex, long-chain fatty acids that are a major component of the cell wall of Mycobacterium species, including the causative agents of tuberculosis and leprosy, providing them with unique characteristics such as resistance to acid-alkali stability, pigmentation, and protection against host immune responses.

Deoxyribonucleic acid that makes up the genetic material of bacteria.

Antibacterial agent used primarily as a tuberculostatic. It remains the treatment of choice for tuberculosis.

The etiologic agent of rat leprosy, also known as murine leprosy.

Substances elaborated by bacteria that have antigenic activity.

A non-tuberculous mycobacterium causing cervical lymphadenitis in children. It very rarely causes pulmonary disease, and is believed to be non-pathogenic in animals.

An active immunizing agent and a viable avirulent attenuated strain of Mycobacterium tuberculosis, var. bovis, which confers immunity to mycobacterial infections. It is used also in immunotherapy of neoplasms due to its stimulation of antibodies and non-specific immunity.

A slow-growing, scotochromogenic species occurring usually harmlessly in human secretions but occasionally associated with chronic pulmonary disease. (Dorland, 28th ed)

A chronic GASTROENTERITIS in RUMINANTS caused by MYCOBACTERIUM AVIUM SUBSPECIES PARATUBERCULOSIS.

An antitubercular agent that inhibits the transfer of mycolic acids into the cell wall of the tubercle bacillus. It may also inhibit the synthesis of spermidine in mycobacteria. The action is usually bactericidal, and the drug can penetrate human cell membranes to exert its lethal effect. (From Smith and Reynard, Textbook of Pharmacology, 1992, p863)

A semisynthetic antibiotic produced from Streptomyces mediterranei. It has a broad antibacterial spectrum, including activity against several forms of Mycobacterium. In susceptible organisms it inhibits DNA-dependent RNA polymerase activity by forming a stable complex with the enzyme. It thus suppresses the initiation of RNA synthesis. Rifampin is bactericidal, and acts on both intracellular and extracellular organisms. (From Gilman et al., Goodman and Gilman's The Pharmacological Basis of Therapeutics, 9th ed, p1160)

A chronic granulomatous infection caused by MYCOBACTERIUM LEPRAE. The granulomatous lesions are manifested in the skin, the mucous membranes, and the peripheral nerves. Two polar or principal types are lepromatous and tuberculoid.

Viruses whose host is one or more Mycobacterium species. They include both temperate and virulent types.

An infection of cattle caused by MYCOBACTERIUM BOVIS. It is transmissible to man and other animals.

Techniques used in studying bacteria.

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.

A species of gram-positive, aerobic bacteria that causes granulomatous or ulcerating skin lesions in immunosuppressed persons. This organism owes its name to its requirement for growth of high levels of iron, conveniently supplied as blood, heme, or ferric ammonium citrate.

Vaccines or candidate vaccines used to prevent or treat TUBERCULOSIS.

Any tests that demonstrate the relative efficacy of different chemotherapeutic agents against specific microorganisms (i.e., bacteria, fungi, viruses).

Material coughed up from the lungs and expectorated via the mouth. It contains MUCUS, cellular debris, and microorganisms. It may also contain blood or pus.

Burrowing, chiefly nocturnal mammals of the family Dasypodidae having bodies and heads encased in small bony plates. They are widely distributed in the warmer parts of the Americas.

Procedures for identifying types and strains of bacteria. The most frequently employed typing systems are BACTERIOPHAGE TYPING and SEROTYPING as well as bacteriocin typing and biotyping.

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.

Tuberculosis resistant to chemotherapy with two or more ANTITUBERCULAR AGENTS, including at least ISONIAZID and RIFAMPICIN. The problem of resistance is particularly troublesome in tuberculous OPPORTUNISTIC INFECTIONS associated with HIV INFECTIONS. It requires the use of second line drugs which are more toxic than the first line regimens. TB with isolates that have developed further resistance to at least three of the six classes of second line drugs is defined as EXTENSIVELY DRUG-RESISTANT TUBERCULOSIS.

The relatively long-lived phagocytic cell of mammalian tissues that are derived from blood MONOCYTES. Main types are PERITONEAL MACROPHAGES; ALVEOLAR MACROPHAGES; HISTIOCYTES; KUPFFER CELLS of the liver; and OSTEOCLASTS. They may further differentiate within chronic inflammatory lesions to EPITHELIOID CELLS or may fuse to form FOREIGN BODY GIANT CELLS or LANGHANS GIANT CELLS. (from The Dictionary of Cell Biology, Lackie and Dow, 3rd ed.)

A pyrazine that is used therapeutically as an antitubercular agent.

A family of multisubunit protein complexes that form into large cylindrical structures which bind to and encapsulate non-native proteins. Chaperonins utilize the energy of ATP hydrolysis to enhance the efficiency of PROTEIN FOLDING reactions and thereby help proteins reach their functional conformation. The family of chaperonins is split into GROUP I CHAPERONINS, and GROUP II CHAPERONINS, with each group having its own repertoire of protein subunits and subcellular preferences.

Any compound containing one or more monosaccharide residues bound by a glycosidic linkage to a hydrophobic moiety such as an acylglycerol (see GLYCERIDES), a sphingoid, a ceramide (CERAMIDES) (N-acylsphingoid) or a prenyl phosphate. (From IUPAC's webpage)

A relatively small nodular inflammatory lesion containing grouped mononuclear phagocytes, caused by infectious and noninfectious agents.

Variation occurring within a species in the presence or length of DNA fragment generated by a specific endonuclease at a specific site in the genome. Such variations are generated by mutations that create or abolish recognition sites for these enzymes or change the length of the fragment.

The functional hereditary units of BACTERIA.

Any liquid or solid preparation made specifically for the growth, storage, or transport of microorganisms or other types of cells. The variety of media that exist allow for the culturing of specific microorganisms and cell types, such as differential media, selective media, test media, and defined media. Solid media consist of liquid media that have been solidified with an agent such as AGAR or GELATIN.

The ability of bacteria to resist or to become tolerant to chemotherapeutic agents, antimicrobial agents, or antibiotics. This resistance may be acquired through gene mutation or foreign DNA in transmissible plasmids (R FACTORS).

A group I chaperonin protein that forms the barrel-like structure of the chaperonin complex. It is an oligomeric protein with a distinctive structure of fourteen subunits, arranged in two rings of seven subunits each. The protein was originally studied in BACTERIA where it is commonly referred to as GroEL protein.

The restriction of a characteristic behavior, anatomical structure or physical system, such as immune response; metabolic response, or gene or gene variant to the members of one species. It refers to that property which differentiates one species from another but it is also used for phylogenetic levels higher or lower than the species.

Toxic glycolipids composed of trehalose dimycolate derivatives. They are produced by MYCOBACTERIUM TUBERCULOSIS and other species of MYCOBACTERIUM. They induce cellular dysfunction in animals.

Constituent of 30S subunit prokaryotic ribosomes containing 1600 nucleotides and 21 proteins. 16S rRNA is involved in initiation of polypeptide synthesis.

The major interferon produced by mitogenically or antigenically stimulated LYMPHOCYTES. It is structurally different from TYPE I INTERFERON and its major activity is immunoregulation. It has been implicated in the expression of CLASS II HISTOCOMPATIBILITY ANTIGENS in cells that do not normally produce them, leading to AUTOIMMUNE DISEASES.

A multistage process that includes cloning, physical mapping, subcloning, determination of the DNA SEQUENCE, and information analysis.

Discrete segments of DNA which can excise and reintegrate to another site in the genome. Most are inactive, i.e., have not been found to exist outside the integrated state. DNA transposable elements include bacterial IS (insertion sequence) elements, Tn elements, the maize controlling elements Ac and Ds, Drosophila P, gypsy, and pogo elements, the human Tigger elements and the Tc and mariner elements which are found throughout the animal kingdom.

A technique for identifying individuals of a species that is based on the uniqueness of their DNA sequence. Uniqueness is determined by identifying which combination of allelic variations occur in the individual at a statistically relevant number of different loci. In forensic studies, RESTRICTION FRAGMENT LENGTH POLYMORPHISM of multiple, highly polymorphic VNTR LOCI or MICROSATELLITE REPEAT loci are analyzed. The number of loci used for the profile depends on the ALLELE FREQUENCY in the population.

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)

A protein extracted from boiled culture of tubercle bacilli (MYCOBACTERIUM TUBERCULOSIS). It is used in the tuberculin skin test (TUBERCULIN TEST) for the diagnosis of tuberculosis infection in asymptomatic persons.

The sequence of PURINES and PYRIMIDINES in nucleic acids and polynucleotides. It is also called nucleotide sequence.

An antibiotic produced by the soil actinomycete Streptomyces griseus. It acts by inhibiting the initiation and elongation processes during protein synthesis.

One of several skin tests to determine past or present tuberculosis infection. A purified protein derivative of the tubercle bacilli, called tuberculin, is introduced into the skin by scratch, puncture, or interdermal injection.

Any of the processes by which cytoplasmic or intercellular factors influence the differential control of gene action in bacteria.

Substances that reduce the growth or reproduction of BACTERIA.

Enumeration by direct count of viable, isolated bacterial, archaeal, or fungal CELLS or SPORES capable of growth on solid CULTURE MEDIA. The method is used routinely by environmental microbiologists for quantifying organisms in AIR; FOOD; and WATER; by clinicians for measuring patients' microbial load; and in antimicrobial drug testing.

A second-line antitubercular agent that inhibits mycolic acid synthesis.

A family of gram-positive bacteria found in soil and dairy products and as parasites on animals and man. Several are important pathogens.

The genetic complement of a BACTERIA as represented in its DNA.

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.

A fat-soluble riminophenazine dye used for the treatment of leprosy. It has been used investigationally in combination with other antimycobacterial drugs to treat Mycobacterium avium infections in AIDS patients. Clofazimine also has a marked anti-inflammatory effect and is given to control the leprosy reaction, erythema nodosum leprosum. (From AMA Drug Evaluations Annual, 1993, p1619)

Either of the pair of organs occupying the cavity of the thorax that effect the aeration of the blood.

The outermost layer of a cell in most PLANTS; BACTERIA; FUNGI; and ALGAE. The cell wall is usually a rigid structure that lies external to the CELL MEMBRANE, and provides a protective barrier against physical or chemical agents.

Ribonucleic acid in bacteria having regulatory and catalytic roles as well as involvement in protein synthesis.

Cyclic peptide antibiotic similar to VIOMYCIN. It is produced by Streptomyces capreolus.

Membrane-bound cytoplasmic vesicles formed by invagination of phagocytized material. They fuse with lysosomes to form phagolysosomes in which the hydrolytic enzymes of the lysosome digest the phagocytized material.

The relationships of groups of organisms as reflected by their genetic makeup.

The degree of pathogenicity within a group or species of microorganisms or viruses as indicated by case fatality rates and/or the ability of the organism to invade the tissues of the host. The pathogenic capacity of an organism is determined by its VIRULENCE FACTORS.

Tandem arrays of moderately repetitive, short (10-60 bases) DNA sequences which are found dispersed throughout the GENOME, at the ends of chromosomes (TELOMERES), and clustered near telomeres. Their degree of repetition is two to several hundred at each locus. Loci number in the thousands but each locus shows a distinctive repeat unit.

Substances that suppress Mycobacterium leprae, ameliorate the clinical manifestations of leprosy, and/or reduce the incidence and severity of leprous reactions.

Immunoglobulins produced in a response to BACTERIAL ANTIGENS.

Ability of a microbe to survive under given conditions. This can also be related to a colony's ability to replicate.

The ability of microorganisms, especially bacteria, to resist or to become tolerant to chemotherapeutic agents, antimicrobial agents, or antibiotics. This resistance may be acquired through gene mutation or foreign DNA in transmissible plasmids (R FACTORS).

Domesticated bovine animals of the genus Bos, usually kept on a farm or ranch and used for the production of meat or dairy products or for heavy labor.

A broad-spectrum antibiotic that is being used as prophylaxis against disseminated Mycobacterium avium complex infection in HIV-positive patients.

Inbred C57BL mice are a strain of laboratory mice that have been produced by many generations of brother-sister matings, resulting in a high degree of genetic uniformity and homozygosity, making them widely used for biomedical research, including studies on genetics, immunology, cancer, and neuroscience.

Skin diseases caused by bacteria.

Commercially prepared reagent sets, with accessory devices, containing all of the major components and literature necessary to perform one or more designated diagnostic tests or procedures. They may be for laboratory or personal use.

A semisynthetic macrolide antibiotic derived from ERYTHROMYCIN that is active against a variety of microorganisms. It can inhibit PROTEIN SYNTHESIS in BACTERIA by reversibly binding to the 50S ribosomal subunits. This inhibits the translocation of aminoacyl transfer-RNA and prevents peptide chain elongation.

Opportunistic infections found in patients who test positive for human immunodeficiency virus (HIV). The most common include PNEUMOCYSTIS PNEUMONIA, Kaposi's sarcoma, cryptosporidiosis, herpes simplex, toxoplasmosis, cryptococcosis, and infections with Mycobacterium avium complex, Microsporidium, and Cytomegalovirus.

Studies determining the effectiveness or value of processes, personnel, and equipment, or the material on conducting such studies. For drugs and devices, CLINICAL TRIALS AS TOPIC; DRUG EVALUATION; and DRUG EVALUATION, PRECLINICAL are available.

A chronic communicable infection which is a principal or polar form of LEPROSY. This disorder is caused by MYCOBACTERIUM LEPRAE and produces diffuse granulomatous skin lesions in the form of nodules, macules, or papules. The peripheral nerves are involved symmetrically and neural sequelae occur in the advanced stage.

Inflammation of the lymph nodes.

Chromatography on thin layers of adsorbents rather than in columns. The adsorbent can be alumina, silica gel, silicates, charcoals, or cellulose. (McGraw-Hill Dictionary of Scientific and Technical Terms, 4th ed)

Measurable quantity of bacteria in an object, organism, or organism compartment.

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.

Infection of the lymph nodes by tuberculosis. Tuberculous infection of the cervical lymph nodes is scrofula.

DNA sequences encoding RIBOSOMAL RNA and the segments of DNA separating the individual ribosomal RNA genes, referred to as RIBOSOMAL SPACER DNA.

Inbred BALB/c mice are a strain of laboratory mice that have been selectively bred to be genetically identical to each other, making them useful for scientific research and experiments due to their consistent genetic background and predictable responses to various stimuli or treatments.

Diseases of domestic cattle of the genus Bos. It includes diseases of cows, yaks, and zebus.

An increased reactivity to specific antigens mediated not by antibodies but by cells.

The genetic constitution of the individual, comprising the ALLELES present at each GENETIC LOCUS.

An encapsulated lymphatic organ through which venous blood filters.

Species- or subspecies-specific DNA (including COMPLEMENTARY DNA; conserved genes, whole chromosomes, or whole genomes) used in hybridization studies in order to identify microorganisms, to measure DNA-DNA homologies, to group subspecies, etc. The DNA probe hybridizes with a specific mRNA, if present. Conventional techniques used for testing for the hybridization product include dot blot assays, Southern blot assays, and DNA:RNA hybrid-specific antibody tests. Conventional labels for the DNA probe include the radioisotope labels 32P and 125I and the chemical label biotin. The use of DNA probes provides a specific, sensitive, rapid, and inexpensive replacement for cell culture techniques for diagnosing infections.

The ability of bacteria to resist or to become tolerant to several structurally and functionally distinct drugs simultaneously. This resistance may be acquired through gene mutation or foreign DNA in transmissible plasmids (R FACTORS).

A group of ANTI-BACTERIAL AGENTS characterized by a chromophoric naphthohydroquinone group spanned by an aliphatic bridge not previously found in other known ANTI-BACTERIAL AGENTS. They have been isolated from fermentation broths of Streptomyces mediterranei.

A variety of TUBERCULOSIS affecting various birds, including chickens and ducks. It is caused by MYCOBACTERIUM AVIUM and characterized by tubercles consisting principally of epithelioid cells.

A broad-spectrum antibiotic derived from KANAMYCIN. It is reno- and oto-toxic like the other aminoglycoside antibiotics.

A form of bacterial meningitis caused by MYCOBACTERIUM TUBERCULOSIS or rarely MYCOBACTERIUM BOVIS. The organism seeds the meninges and forms microtuberculomas which subsequently rupture. The clinical course tends to be subacute, with progressions occurring over a period of several days or longer. Headache and meningeal irritation may be followed by SEIZURES, cranial neuropathies, focal neurologic deficits, somnolence, and eventually COMA. The illness may occur in immunocompetent individuals or as an OPPORTUNISTIC INFECTION in the ACQUIRED IMMUNODEFICIENCY SYNDROME and other immunodeficiency syndromes. (From Adams et al., Principles of Neurology, 6th ed, pp717-9)

The application of molecular biology to the answering of epidemiological questions. The examination of patterns of changes in DNA to implicate particular carcinogens and the use of molecular markers to predict which individuals are at highest risk for a disease are common examples.

Tuberculosis of the skin. It includes scrofuloderma and tuberculid, but not LUPUS VULGARIS.

MOLECULAR BIOLOGY techniques used in the diagnosis of disease.

The insertion of recombinant DNA molecules from prokaryotic and/or eukaryotic sources into a replicating vehicle, such as a plasmid or virus vector, and the introduction of the resultant hybrid molecules into recipient cells without altering the viability of those cells.

Enzymes from the transferase class that catalyze the transfer of acyl groups from donor to acceptor, forming either esters or amides. (From Enzyme Nomenclature 1992) EC 2.3.

Short sequences (generally about 10 base pairs) of DNA that are complementary to sequences of messenger RNA and allow reverse transcriptases to start copying the adjacent sequences of mRNA. Primers are used extensively in genetic and molecular biology techniques.

Using MOLECULAR BIOLOGY techniques, such as DNA SEQUENCE ANALYSIS; PULSED-FIELD GEL ELECTROPHORESIS; and DNA FINGERPRINTING, to identify, classify, and compare organisms and their subtypes.

The intergenic DNA segments that are between the ribosomal RNA genes (internal transcribed spacers) and between the tandemly repeated units of rDNA (external transcribed spacers and nontranscribed spacers).

Elements of limited time intervals, contributing to particular results or situations.

A skin ulcer is a breakdown of the skin's surface and underlying tissues, often caused by prolonged pressure, infection, or poor circulation, leading to a loss of continuity in the epidermis and dermis, potentially extending into deeper layers such as subcutaneous tissue, muscle, and bone.

Proteins which contain carbohydrate groups attached covalently to the polypeptide chain. The protein moiety is the predominant group with the carbohydrate making up only a small percentage of the total weight.

Copies of transposable elements interspersed throughout the genome, some of which are still active and often referred to as "jumping genes". There are two classes of interspersed repetitive elements. Class I elements (or RETROELEMENTS - such as retrotransposons, retroviruses, LONG INTERSPERSED NUCLEOTIDE ELEMENTS and SHORT INTERSPERSED NUCLEOTIDE ELEMENTS) transpose via reverse transcription of an RNA intermediate. Class II elements (or DNA TRANSPOSABLE ELEMENTS - such as transposons, Tn elements, insertion sequence elements and mobile gene cassettes of bacterial integrons) transpose directly from one site in the DNA to another.

Sorbitan mono-9-octadecanoate poly(oxy-1,2-ethanediyl) derivatives; complex mixtures of polyoxyethylene ethers used as emulsifiers or dispersing agents in pharmaceuticals.

A principal or polar form of LEPROSY in which the skin lesions are few and are sharply demarcated. Peripheral nerve involvement is pronounced and may be severe. Unlike lepromatous leprosy (LEPROSY, LEPROMATOUS), the lepromin test is positive. Tuberculoid leprosy is rarely a source of infection to others.

Lymphocytes responsible for cell-mediated immunity. Two types have been identified - cytotoxic (T-LYMPHOCYTES, CYTOTOXIC) and helper T-lymphocytes (T-LYMPHOCYTES, HELPER-INDUCER). They are formed when lymphocytes circulate through the THYMUS GLAND and differentiate to thymocytes. When exposed to an antigen, they divide rapidly and produce large numbers of new T cells sensitized to that antigen.

An immunoassay utilizing an antibody labeled with an enzyme marker such as horseradish peroxidase. While either the enzyme or the antibody is bound to an immunosorbent substrate, they both retain their biologic activity; the change in enzyme activity as a result of the enzyme-antibody-antigen reaction is proportional to the concentration of the antigen and can be measured spectrophotometrically or with the naked eye. Many variations of the method have been developed.

The use of devices which use detector molecules to detect, investigate, or analyze other molecules, macromolecules, molecular aggregates, or organisms.

Proteins prepared by recombinant DNA technology.

Five-membered heterocyclic ring structures containing an oxygen in the 1-position and a nitrogen in the 3-position, in distinction from ISOXAZOLES where they are at the 1,2 positions.

The process of altering the morphology and functional activity of macrophages so that they become avidly phagocytic. It is initiated by lymphokines, such as the macrophage activation factor (MAF) and the macrophage migration-inhibitory factor (MMIF), immune complexes, C3b, and various peptides, polysaccharides, and immunologic adjuvants.

A set of statistical methods used to group variables or observations into strongly inter-related subgroups. In epidemiology, it may be used to analyze a closely grouped series of events or cases of disease or other health-related phenomenon with well-defined distribution patterns in relation to time or place or both.

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.

A bacterial DNA topoisomerase II that catalyzes ATP-dependent breakage of both strands of DNA, passage of the unbroken strands through the breaks, and rejoining of the broken strands. Gyrase binds to DNA as a heterotetramer consisting of two A and two B subunits. In the presence of ATP, gyrase is able to convert the relaxed circular DNA duplex into a superhelix. In the absence of ATP, supercoiled DNA is relaxed by DNA gyrase.

The degree of similarity between sequences of amino acids. This information is useful for the analyzing genetic relatedness of proteins and species.

Morphologic alteration of small B LYMPHOCYTES or T LYMPHOCYTES in culture into large blast-like cells able to synthesize DNA and RNA and to divide mitotically. It is induced by INTERLEUKINS; MITOGENS such as PHYTOHEMAGGLUTININS, and by specific ANTIGENS. It may also occur in vivo as in GRAFT REJECTION.

Non-antibody proteins secreted by inflammatory leukocytes and some non-leukocytic cells, that act as intercellular mediators. They differ from classical hormones in that they are produced by a number of tissue or cell types rather than by specialized glands. They generally act locally in a paracrine or autocrine rather than endocrine manner.

The arrangement of two or more amino acid or base sequences from an organism or organisms in such a way as to align areas of the sequences sharing common properties. The degree of relatedness or homology between the sequences is predicted computationally or statistically based on weights assigned to the elements aligned between the sequences. This in turn can serve as a potential indicator of the genetic relatedness between the organisms.

The study of crystal structure using X-RAY DIFFRACTION techniques. (McGraw-Hill Dictionary of Scientific and Technical Terms, 4th ed)

A genus of gram-positive, aerobic bacteria whose species are widely distributed and are abundant in soil. Some strains are pathogenic opportunists for humans and animals.

A genetic rearrangement through loss of segments of DNA or RNA, bringing sequences which are normally separated into close proximity. This deletion may be detected using cytogenetic techniques and can also be inferred from the phenotype, indicating a deletion at one specific locus.

Lepromin is a sterile suspension of Mycobacterium leprae, utilized in intradermal tests to determine the type of immune response in leprosy patients, distinguishing between tuberculoid and lepromatous forms.

A tumor-like mass resulting from the enlargement of a tuberculous lesion.

Manifestations of the immune response which are mediated by antigen-sensitized T-lymphocytes via lymphokines or direct cytotoxicity. This takes place in the absence of circulating antibody or where antibody plays a subordinate role.

Laboratory techniques that involve the in-vitro synthesis of many copies of DNA or RNA from one original template.

A common name used for the genus Cavia. The most common species is Cavia porcellus which is the domesticated guinea pig used for pets and biomedical research.

The engulfing and degradation of microorganisms; other cells that are dead, dying, or pathogenic; and foreign particles by phagocytic cells (PHAGOCYTES).

A thiosemicarbazone that is used in association with other antimycobacterial agents in the initial and continuation phases of antituberculosis regimens. Thiacetazone containing regimens are less effective than the short-course regimen recommended by the International Union Against Tuberculosis and are used in some developing countries to reduce drug costs. (From Martindale, The Extra Pharmacopoeia, 30th ed, p217)

The dormant form of TUBERCULOSIS where the person shows no obvious symptoms and no sign of the causative agent (Mycobacterium tuberculosis) in the SPUTUM despite being positive for tuberculosis infection skin test.

A species of gram-negative, facultatively anaerobic, rod-shaped bacteria (GRAM-NEGATIVE FACULTATIVELY ANAEROBIC RODS) commonly found in the lower part of the intestine of warm-blooded animals. It is usually nonpathogenic, but some strains are known to produce DIARRHEA and pyogenic infections. Pathogenic strains (virotypes) are classified by their specific pathogenic mechanisms such as toxins (ENTEROTOXIGENIC ESCHERICHIA COLI), etc.

Tuberculosis of the serous membrane lining the thoracic cavity and surrounding the lungs.

The presence of bacteria, viruses, and fungi in water. This term is not restricted to pathogenic organisms.

'Azā compounds' are a class of organic molecules containing at least one nitrogen atom in a five-membered ring, often found in naturally occurring substances and pharmaceuticals, with the name derived from the Arabic word "azZa" meaning 'strong' referring to the ring's aromatic stability.

Constituent of 50S subunit of prokaryotic ribosomes containing about 3200 nucleotides. 23S rRNA is involved in the initiation of polypeptide synthesis.

Epicutaneous or intradermal application of a sensitizer for demonstration of either delayed or immediate hypersensitivity. Used in diagnosis of hypersensitivity or as a test for cellular immunity.

Pathological processes involving any part of the LUNG.

A pattern recognition receptor that forms heterodimers with other TOLL-LIKE RECEPTORS. It interacts with multiple ligands including PEPTIDOGLYCAN, bacterial LIPOPROTEINS, lipoarabinomannan, and a variety of PORINS.

Infection of the spleen with species of MYCOBACTERIUM.

Amidohydrolases are enzymes that catalyze the hydrolysis of amides and related compounds, playing a crucial role in various biological processes including the breakdown and synthesis of bioactive molecules.

Substances that prevent infectious agents or organisms from spreading or kill infectious agents in order to prevent the spread of infection.

Peroxidases are enzymes that catalyze the reduction of hydrogen peroxide to water, while oxidizing various organic and inorganic compounds, playing crucial roles in diverse biological processes including stress response, immune defense, and biosynthetic reactions.

The family Cervidae of 17 genera and 45 species occurring nearly throughout North America, South America, and Eurasia, on most associated continental islands, and in northern Africa. Wild populations of deer have been established through introduction by people in Cuba, New Guinea, Australia, New Zealand, and other places where the family does not naturally occur. They are slim, long-legged and best characterized by the presence of antlers. Their habitat is forests, swamps, brush country, deserts, and arctic tundra. They are usually good swimmers; some migrate seasonally. (Walker's Mammals of the World, 5th ed, p1362)

A highly caustic substance that is used to neutralize acids and make sodium salts. (From Merck Index, 11th ed)

Models used experimentally or theoretically to study molecular shape, electronic properties, or interactions; includes analogous molecules, computer-generated graphics, and mechanical structures.

Administration of vaccines to stimulate the host's immune response. This includes any preparation intended for active immunological prophylaxis.

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.

Serological reactions in which an antiserum against one antigen reacts with a non-identical but closely related antigen.

An oxidoreductase that catalyzes the conversion of HYDROGEN PEROXIDE to water and oxygen. It is present in many animal cells. A deficiency of this enzyme results in ACATALASIA.

A group of often glycosylated macrocyclic compounds formed by chain extension of multiple PROPIONATES cyclized into a large (typically 12, 14, or 16)-membered lactone. Macrolides belong to the POLYKETIDES class of natural products, and many members exhibit ANTIBIOTIC properties.

A test used to determine whether or not complementation (compensation in the form of dominance) will occur in a cell with a given mutant phenotype when another mutant genome, encoding the same mutant phenotype, is introduced into that cell.

The ability of lymphoid cells to mount a humoral or cellular immune response when challenged by antigen.

A class of quinoline compounds defined by the presence of two aromatic ring structures which are attached via a side chain to carbon 3 of the qunolinyl structure. The two aromatic moieties are typically NAPTHALENE and BENZENE. Several compounds in this class are used as ANTITUBERCULAR AGENTS.

A group of QUINOLONES with at least one fluorine atom and a piperazinyl group.

Large, phagocytic mononuclear leukocytes produced in the vertebrate BONE MARROW and released into the BLOOD; contain a large, oval or somewhat indented nucleus surrounded by voluminous cytoplasm and numerous organelles.

The interactions between a host and a pathogen, usually resulting in disease.

The capacity of a normal organism to remain unaffected by microorganisms and their toxins. It results from the presence of naturally occurring ANTI-INFECTIVE AGENTS, constitutional factors such as BODY TEMPERATURE and immediate acting immune cells such as NATURAL KILLER CELLS.

An aniline dye used as a disinfectant and an antiseptic agent. It is weakly fluorescing and binds specifically to certain proteins.

Tuberculosis resistant to ISONIAZID and RIFAMPIN and at least three of the six main classes of second-line drugs (AMINOGLYCOSIDES; polypeptide agents; FLUOROQUINOLONES; THIOAMIDES; CYCLOSERINE; and PARA-AMINOSALICYLIC ACID) as defined by the CDC.

A synthetic fluoroquinolone antibacterial agent that inhibits the supercoiling activity of bacterial DNA GYRASE, halting DNA REPLICATION.

A family of hemoglobin-like proteins found in BACTERIA; PLANTS; and unicellular eukaryotes. Truncated hemoglobins are distantly related to vertebrate hemoglobins and are typically shorter than vertebrate hemoglobins by 20-40 residues.

Antibiotic complex produced by Streptomyces kanamyceticus from Japanese soil. Comprises 3 components: kanamycin A, the major component, and kanamycins B and C, the minor components.

The class of all enzymes catalyzing oxidoreduction reactions. The substrate that is oxidized is regarded as a hydrogen donor. The systematic name is based on donor:acceptor oxidoreductase. The recommended name will be dehydrogenase, wherever this is possible; as an alternative, reductase can be used. Oxidase is only used in cases where O2 is the acceptor. (Enzyme Nomenclature, 1992, p9)

Procedures for collecting, preserving, and transporting of specimens sufficiently stable to provide accurate and precise results suitable for clinical interpretation.

A critical subpopulation of T-lymphocytes involved in the induction of most immunological functions. The HIV virus has selective tropism for the T4 cell which expresses the CD4 phenotypic marker, a receptor for HIV. In fact, the key element in the profound immunosuppression seen in HIV infection is the depletion of this subset of T-lymphocytes.

Any technique by which an unknown color is evaluated in terms of standard colors. The technique may be visual, photoelectric, or indirect by means of spectrophotometry. It is used in chemistry and physics. (McGraw-Hill Dictionary of Scientific and Technical Terms, 4th ed)

The study of microorganisms living in a variety of environments (air, soil, water, etc.) and their pathogenic relationship to other organisms including man.

They are oval or bean shaped bodies (1 - 30 mm in diameter) located along the lymphatic system.

Widely used technique which exploits the ability of complementary sequences in single-stranded DNAs or RNAs to pair with each other to form a double helix. Hybridization can take place between two complimentary DNA sequences, between a single-stranded DNA and a complementary RNA, or between two RNA sequences. The technique is used to detect and isolate specific sequences, measure homology, or define other characteristics of one or both strands. (Kendrew, Encyclopedia of Molecular Biology, 1994, p503)

The outward appearance of the individual. It is the product of interactions between genes, and between the GENOTYPE and the environment.

Organic, monobasic acids derived from hydrocarbons by the equivalent of oxidation of a methyl group to an alcohol, aldehyde, and then acid. Fatty acids are saturated and unsaturated (FATTY ACIDS, UNSATURATED). (Grant & Hackh's Chemical Dictionary, 5th ed)

The location of the atoms, groups or ions relative to one another in a molecule, as well as the number, type and location of covalent bonds.

Enzymes that catalyze DNA template-directed extension of the 3'-end of an RNA strand one nucleotide at a time. They can initiate a chain de novo. In eukaryotes, three forms of the enzyme have been distinguished on the basis of sensitivity to alpha-amanitin, and the type of RNA synthesized. (From Enzyme Nomenclature, 1992).

Six-membered heterocycles containing an oxygen and a nitrogen.

Incorrect diagnoses after clinical examination or technical diagnostic procedures.

Mature LYMPHOCYTES and MONOCYTES transported by the blood to the body's extravascular space. They are morphologically distinguishable from mature granulocytic leukocytes by their large, non-lobed nuclei and lack of coarse, heavily stained cytoplasmic granules.

Lipid-containing polysaccharides which are endotoxins and important group-specific antigens. They are often derived from the cell wall of gram-negative bacteria and induce immunoglobulin secretion. The lipopolysaccharide molecule consists of three parts: LIPID A, core polysaccharide, and O-specific chains (O ANTIGENS). When derived from Escherichia coli, lipopolysaccharides serve as polyclonal B-cell mitogens commonly used in laboratory immunology. (From Dorland, 28th ed)

A sulfone active against a wide range of bacteria but mainly employed for its actions against MYCOBACTERIUM LEPRAE. Its mechanism of action is probably similar to that of the SULFONAMIDES which involves inhibition of folic acid synthesis in susceptible organisms. It is also used with PYRIMETHAMINE in the treatment of malaria. (From Martindale, The Extra Pharmacopoeia, 30th ed, p157-8)

Antibiotic substance produced by Streptomyces garyphalus.

Granulomatous disorders affecting one or more sites in the respiratory tract.