Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0029713 (immaturity)
 4,335 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The direction of differentiation of the stem cells with respect to the physiological activity of thymus determined by the age of an animal was studied by means of histological analysis of hemopoietic colonies in the spleen of lethally irradiated mice. The immaturity of thymus of its involution are characterized by the inhibition of differentiation of the stem cell along the granuloid path. An analysis of the data on differentiation of the stem cells in mice of different age, as well as in thymectomized mice allows to draw a conclusion that the process of differentiation of the hemopoietic stem cells is thymus-dependent.
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PMID:[Relationship between hematopoietic stem differentiation and the functional state of the thymus]. 2 66

A specific antiandrogenic steroid cyproterone acetate was administered daily to mice of three different inbred strains starting from the day of birth until the age of 30 days. The total dose per mouse was 17.2 mg. This treatment resulted in developmental retardation which was manifested in a number of ways: at the age of 30 days, the weight of the body was well as spleen, testes and particularly thymus was significantly reduced; histologically, the normal proportion of the red and white pulp in the spleen was changes; spermatogenesis (but not oogenesis) was markedly retarded corresponding to the age of 12-15 days in normal males; also skin displayed a persisting immaturity as reflected by an abundance of mast cells. Minor signs of toxic changes were seen in the liver. Skin grafts from CA-pretreated donors had a subnormal immunogenicity; when transplanted across the MSA-barrier, they survived significantly longer than control grafts and about 23% took. Significantly prolonged survival was also observed with H-3 incompatible skin grafts from CA-pretreated donors, particularly from male donors. Across the barrier dicated, but did not reach a level of significance. The present study extends our previous observations concerning the androgen dependence of a normal immunogenic expression of H-antigens. The antiandrogenic effect of CA is comparable to the more complex effect of neonatal orchiectomy in terms of the subnormal immunogeneity of MSA-incompatible skin grafts from 30-day-old males which seems to be arrated at a stage typical for 1-2-day-old normal males.
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PMID:Retardation of development including immunogenic expression of histocompatibility antigens in mice--by postnatal administration of antiandrogenic steroid. 4

Considerable thymidine kinase and pyrroline-5-carboxylate reductase activities were found in the plasma of rats bearing a transplanted lymphoma; neither activity was detected in plasma of hosts carrying hepatic, renal, mammary, or submaxillary gland tumors. All host livers exhibited signs of biochemical immaturity as indicated by the appropriate increases or decreases in the concentrations of the nine enzymes measured. The extent and time schedule of the changes in host liver varied with the enzyme and with the tumor that caused them. The hepatic concentrations of ornithine aminotransferase, arginase, pyrroline-5-carboxylate reductase, and glucokinase (all diminished), and of peptidyl proline hydroxylase and hexokinase (increased) were sensitive indicators of tumor growth in general. The concentration of ornithine aminotransferase decreased before the tumors became palpable. At more advanced stages, the high hepatic thymidine kinase activity distinguished the presence of hepatoma and lymphoma from those of all other equally fast-growing tumors. However, only in lymphoma-bearing rats did a fivefold elevation of hepatic thymidine kinase occur as early as 4 days after implantation. Additional observations on the lymphoma itself, on blood cells, and on the involuting thymus of normal rats indicate that the striking systemic effects of this tumor cannot be explained by a release of enzymes from the thymus or by the increased number of lymphoma cells present in blood or liver.
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PMID:The effect of lymphoma and other neoplasms on hepatic and plasma enzymes of the host rat. 18 34

Studies were made on the identity of human and monkey mononuclear leukocytes permissive to antibody-enhanced dengue 2 virus (D2V) infection. In cultures of peripheral blood leukocytes (PBL) inoculated immediately after separation, it was concluded that only mononuclear phagocytes support dengue infection. This is based upon observations that D2V-permissive cells were resistant to 1,200 rads, were both plastic adherent and nonadherent, were removed when passed through nylon wool columns in 10 percent fetal bovine serum or 100 percent autologous serum, and were destroyed by incubation with 100 mug/ml particulate silica. On direct immunofluorescence staining, perinuclear dengue antigen was visualized at 24 h, becoming maximal at 60 h. Antigen-containing cells had ample cytoplasm, ruffled cytoplasmic membrane, and 73 percent were actively phagocytic. As further evidence of the infection of mononuclear phagocytes, antibody-enhanced D2V replication was observed in bone marrow cultures from five of five rhesus monkeys, but not in cell cultures of spleen, thymus, or lymph nodes prepared from the same animals. It is hypothesized that dengue virus complexed with non-neutralizing antibody is internalized by immune phagocytosis in a mononuclear phagocyte with a defective virus-destroying mechanism. Dengue permissiveness may depend upon cellular immaturity since bone marrow leukocytes could be infected even when held for 4 days before infection while PBL held for this time decreased in permissiveness. In vitro antibody-dependent infection of mononuclear phagocytes should prove useful as a model for study of immunopathologic mechanisms in human dengue.
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PMID:Dengue viruses and mononuclear phagocytes. II. Identity of blood and tissue leukocytes supporting in vitro infection. 19

The immunologic immaturity of embryos and newly hatched chicks to MRBC immunization has provided us with a model to investigate the distribution of immunocytes and their precursors in several tissues of juvenile chickens. Antigen-responsive cells (ARC) were rare in the peripheral blood, spleen, bone marrow, thymus and bursa of Fabricius of unimmunized young birds. Following MRBC immunization, they were abundant in the blood and spleen, low in frequency in bone marrow and absent in the thymus and bursa. The recipients of bone marrow cells, thymocytes, or bursacytes, when immunized at hatching, exhibited accelerated humoral immune responses. The enhancement property of the grafted cells was increased when MRBC was included in the cell suspension at the time of grafting. The precocious responsiveness of the grafted chicks is attributed to the cooperation of donor and host immunocytes. The enhancement effect, moreover, was less consistently expressed in allogeneic hosts. This capacity was aquired by thymic cells within a day after immunization of the donor and persisted well over a week. The role of antigen in driving the specific differentiation of T and Bu cells is briefly discussed.
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PMID:Kinetic analysis of the enhanced immune responsiveness of baby chicks grafted with lymphoid cells from juvenile donors. 30 63

Susceptibility to tolerance induction by polysaccharides during the neonatal period has been studied with the alpha-1.3 and alpha-1.6 glucosyl epitopes of dextran B1355 in BALB/c mice and the beta-2.6 fructosyl epitope of levan in CBA mice. Acquisition of responsiveness, as measured by plaque-forming cell (PFC) assays, is relatively late - taking more than 14 days to appear and 2 - 3 months to attain maturity in the case of alpha-1.6 glucosyl and beta-2.6 fructosy. The mice responded well to sheep red blood cells and 2,4-dinitrophenylated (DNP) keyhole limpet hemocyanin (KLH) by 14 days, but were refractory to another thymus-independent antigen DNP-Ficoll. Nonresponsiveness of 2-week-old spleen cells to the polysaccharides was stable on transfer and could not be attributed to suppressor cells. Despite this long post-natal phase of immaturity, no evidence was obtained of concomitant susceptibility to tolerance induction by textran and levan. Response curves in mice injected at birth with weight-adjusted doses revealed similar or even higher "high-zone" thresholds to those tolerized at 3 months. Only partial alpha-1.3 glucosyl tolerance is inducible in adults but this was no greater after neonatal exposure, which led also to short-lived alpha-1.6 tolerance. Repeated injections of B1355 and levan during the first 10 days was no more tolerogenic and PFC appeared spontaneously with maturity in mice given these antigens neonatally. Thus, the recognized neonatal susceptibility to thymus-dependent antigens does not extend to these thymus-independent antigens. It is therefore considered that tolerance studied with polysaccharides has little relevance to the mechanism of self-tolerance acquired in the embryo and, in vivo, is determined by interaction with a relatively mature B cell rather than by "clonal abortion" of a tolerance-sensitive precursor stage.
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PMID:Lack of neonatal susceptibility to induction of tolerance by polysaccharide antigens. 108 89

During fetal life, both Ig and TCR-gamma delta repertoires are enriched for a specific set of Ag receptors with limited diversity. In order to test the hypothesis that diversification of the human TCR-beta repertoire also follows a developmental program, we examined TCR-beta DJ and VDJ transcripts from fetal and adult thymi. A consistent bias for D beta 1.1 and J beta 1.1 was present in DJ transcripts amplified from 8-wk gestation thymi. Although it is possible to splice and translate D beta 1.1 in all three reading frames, 8-wk gestation fetal DJ transcripts were enriched for D beta 1.1 spliced to J beta 1.1 in reading frame one. Preference for D beta 1.1 reading frame one and for use of J beta 1.1 dwindled with increasing gestational age. Reading frame bias was not affected by the insertion of non-germ-line-encoded nucleotides (N regions) or by the site of gene splicing. In contrast, choice of reading frame and use of J beta 1.1 appeared random in VDJ transcripts from the same 8-wk gestation and adult thymic samples. Among the occasional VDJ transcripts that contained D beta 1.1-J beta 1.1 rearrangements, use of D beta reading frame one was rare. Up to 75% of DJ and VDJ transcripts at 8-wk gestation lacked N regions. Both the percentage of DJ and VDJ transcripts with N regions and the average number of inserted nucleotides per transcript increased with gestational age. Primarily as a result of enhanced N region addition, both the length and sequence diversity of the VDJ junctions increased markedly from 8-wk gestation to adult life with a concomitant increase in the potential size of the TCR-alpha beta repertoire. Terminal deoxynucleotidyl-transferase (TdT), the enzyme associated with N region addition, has not been detected in thymus before 19 wk of gestation. However, we were able to amplify TdT mRNA from all fetal thymi examined. This suggests that TdT may be expressed as early as 8 wk gestation, although at low levels. The early fetal thymus appears enriched for a population of thymocytes that produce minimal quantities of TdT, express a special set of TCR-beta DJ transcripts, and generate a TCR-beta repertoire with limited diversity. These findings support the hypothesis that limitations in the diversity of the TCR repertoire imposed at the time of gene rearrangement contribute to the immaturity of the fetal immune response.
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PMID:Developmental regulation of D beta reading frame and junctional diversity in T cell receptor-beta transcripts from human thymus. 131 Jul 10

The effects of intake of acetaldehyde, the proximal metabolite of ethanol, were studied in two groups of Fischer strain rats. Virgin rats were mated at 3 months of age or at 8 months of age. The acetaldehyde intake group (AcH) was given a 2% aqueous solution of acetaldehyde for the first time on the first day of pregnancy. The solution was then given once a day, oral net acetaldehyde 240 mg/kg b.w. through gestation, labor and lactation. The control group was not exposed to acetaldehyde. Comparative observations were made on both maternal rats and their offspring. 1) Maternal body weight gain between the first and 20th day of pregnancy was significantly low in the AcH group compared with the control group (3-month-old: p less than 0.05, 8-month-old: p less than 0.05). As for placental weight, 3-month-old AcH mothers showed no significant differences from the controls, whereas 8-month-old AcH mothers weighed significantly less than those in the control group (p less than 0.01). Histological investigation disclosed that the brain, liver, and kidney had slight changes in all AcH mothers, whereas the control group showed almost no changes. 2) The average number of fetuses at the 20th day of gestation, neonates per litter, did not significantly differ among the groups. 3) As for the body weight of the offspring of 3-month-old mothers, the AcH neonates and 10-day-old offspring weighed significantly less than those in the control group (p less than 0.01, p less than 0.01). In the case of 8-month-old mothers, the AcH fetuses at the 20th day of gestation and neonates weighed significantly less than the controls (p less than 0.01, p less than 0.01). 4) Histological study of the brain, lung, liver, kidney, and thymus in offspring revealed remarkable visceral immaturity and hemorrhage in the AcH group, as compared to the controls.
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PMID:[Effects of acetaldehyde exposure on maternal rats and their offspring]. 152 30

The effects of ethanol intake were studied in the three groups of Fischer strain rats. The EtOH-F group began drinking freely at 29 days of age and continued all through mating, pregnancy, delivery, and lactation days. They drank a 10% aqueous solution of ethanol, with net ethyl alcohol 9.7 g/kg b. w. on average. The EtOH-P group drank a 20% aqueous solution of ethanol for the first time on the first day of pregnancy. The solution was then given periodically once a day, oral net ethyl alcohol 3.8 g/kg b. w., through gestation, labor, and lactation. The control group was not exposed to ethanol. Comparative observation were made on both maternal rats and their offspring. 1) Maternal rats: Maternal body weight gain between the first and 20th days of pregnancy was significantly low in the two drinking groups (EtOH-F:p less than 0.01, EtOH-P:p less than 0.01), compared with the control group. Comparing the EtOH-F and the EtOH-P, it was found that body weight gain during the 20 days of pregnancy was significantly depressed in the former group (p less than 0.05). There were no significant differences in placental weight among the three groups. Histological findings disclosed that the brain, liver, and kidney had moderate changes in the EtOH-F, whereas the control showed only slight changes. 2) The average number of fetuses at the 20th day of gestation, neonates per litter, did not significantly different among the three groups. The body weights of fetuses at the 20th day of gestation, of neonates and 10-day-old offspring were recorded. In the case of the EtOH-P group, significantly low values (p less than 0.05, p less than 0.01, p less than 0.01) compared with the respective controls. In the case of the EtOH-F group, the differences were non-significant, p less than 0.01 and p less than 0.01 respectively. 3) Histological study of the brain, lung, liver, kidney, and thymus in offspring revealed that remarkable visceral immaturity and hemorrhage were in the EtOH-P and the EtOH-F groups as compared to the control, and they were more pronounced in the EtOH-F group than in the EtOH-P group. 4) Different ways of ethanol administration brought about different results: The EtOH-P group showed a clearer tendency to have low-body-weight of offspring than those the EtOH-F group.(ABSTRACT TRUNCATED AT 400 WORDS)
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PMID:[Effects of ethanol exposure beginning at an early age on maternal rat and their offspring]. 178 62

We performed clinicopathological studies on early-onset sepsis (5 infants, less than 72 hours of life, EOS) and late-onset sepsis (15 infants, greater than 72 hours, LOS) of very low birth weight, less than 1500 g (VLBW). In EOS, the clinical features mimic the respiratory distress syndrome and hematological changes were not observed. The lungs showed slight interstitial pneumonia with structural immaturity, hyaline membranes, hemorrhage, and minimal infiltration by polymorphonuclear neutrophils (PMNs). The pathogen was group B streptococcus or weakly gram-negative bacilli. In LOS, pneumonia proceeded to sepsis and neutropenia with elevated numbers of circulating immature neutrophils, and increased levels of C-reactive protein were observed at the onset of sepsis. Severe pneumonia with infiltration of numerous PMNs and bacterial colonies and polymicrobial infection by nosocomial pathogens such as Staphylococcus aureus and Pseudomonas aeruginosa were common. The thymus and spleen weights varied but retained normal structure in EOS. The thymus was depleted of lymphocytes, and the spleen was hypertrophic but poorly reactive against infection in LOS. The pathogenesis of EOS is regarded as being more closely correlated with lung immaturity and circulatory disorder in early life, whereas that of LOS is associated with immunological defenses of the host, potency of the pathogens, and terminal multiple organ failure.
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PMID:Clinicopathological differences between early-onset and late-onset sepsis and pneumonia in very low birth weight infants. 223 61


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