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41.
42.
Cytokine release from irradiated cells has been postulated to start soon after irradiation preceding detectable clinical and pathological manifestation of lung injury. The expression of transforming growth factor beta (TGF), a fibrogenic and radiation-inducible cytokine, was studied from 1–16 weeks after the 15 and 30 Gray (Gy) of thoracic irradiation to rats. Thoracic irradiation caused an increase in TGF protein in bronchoalveolar lavage (BAL) fluid peaking at 3–6 weeks as compared to sham-irradiated control rats. Steady state TGF mRNA expression as shown by whole lung northern blot assay paralleled the TGF protein expression in BAL fluid. The peak of TGF protein increase in BAL fluid between 3 and 6 weeks coincided with the initial influx of inflammatory cells in BAL fluid, but preceded histologically discernable pulmonary fibrosis that was not apparent until 8–10 weeks after irradiation. In conclusion, TGF and mRNA and protein upregulation preceded the radiation-induced pulmonary fibrosis, suggesting a pathogenetic role in the development of radiation fibrosis.  相似文献   
43.
p27Kip1 is a cyclin-dependent kinase inhibitor that regulates the decision to enter S phase or withdraw from the cell cycle. In resting cells, the level of p27Kip1 provides an inhibitory threshold above which G1 cyclin D/E/cyclin-dependent kinases accumulate before activation; however, in cycling cells, p27Kip1 protein is sequestered by high levels of active cyclin D/cyclin-dependent kinase 4 complexes. As a group, the cyclin-dependent kinase inhibitors have been proposed to act as tumor suppressor genes, and several members have been implicated in the pathogenesis of a variety of human cancers. We examined p27Kip1 expression in 116 non-Hodgkin’s lymphomas including 50 cases of MCL (40 typical and 10 blastic variants), 21 follicular lymphomas, 20 diffuse large B-cell lymphomas, 16 chronic lymphocytic leukemias, 8 marginal zone B-cell lymphomas, and 1 splenic marginal zone lymphoma, and correlated its expression with that of the proliferation marker Ki67 (MiB1) and with p53. p27Kip1gene structure was analyzed by Southern blot in the group of MCLs. In all cases of non-Hodgkin’s lymphoma other than MCL, p27Kip1 expression was inversely related to the proliferation index as measured by Ki67. In contrast, in typical MCL, p27Kip1 expression was negative in 35 of 40 (88%) cases, irrespective of the proliferative rate (median 15%; range 2 to 90%). Paradoxically, in the blastic variant of MCL, 8 of 10 (80%) cases showed expression of p27Kip1, despite a high proliferation rate (median 60%; range 32 to 100%). However, the staining in most of the cases was less intense than in the reactive T lymphocytes. Deletions of p27Kip1gene were not found in any of the 25 cases examined. p53 expression was found in 15 of 50 cases of MCL: 7 of 10 (70%) in the blastic variant and 8 of 40 (20%) in the typical MCL (70% vs. 20%, P < 0.0045). These results demonstrate that MCLs, in contrast to other non-Hodgkin’s lymphomas and normal lymphoid tissue, fail to correlate p27Kip1 expression with the proliferation rate. This peculiar uncoupling of p27Kip1 protein expression from the proliferation rate may be related to the high levels of cyclin D1 expressed in MCL and is likely to have profound effects on cell cycle regulation and contribute to the pathogenesis of MCL.  相似文献   
44.
45.
Pubertal neuromaturation, stress sensitivity, and psychopathology   总被引:2,自引:0,他引:2  
Normal adolescent development is often accompanied by transient emotional and behavioral problems. For most individuals with postpubertal-onset adjustment problems, there is a resolution by early adulthood and relative stability through the adult life span. But for a minority, adjustment problems escalate during adolescence and portend the development of serious mental illness in adulthood. In this article, we explore adolescent behavioral changes and neurodevelopmental processes that might contribute to stress sensitivity and vulnerability for the emergence of the mental disorders. Of particular interest is the role that hormonal changes might play in the expression of genetic vulnerabilities for psychopathology. Drawing on recent findings from clinical research and behavioral neuroscience, we describe the ways in which postpubertal hormones might alter brain function and, thereby, behavior. It is concluded that there are both activational and organization effects of hormones on the adolescent brain, and these contribute to developmental discontinuities in behavioral adjustment. Implications for adult psychopathology and preventive intervention are discussed.  相似文献   
46.
Two or three graded infections with oocysts of Eimeria acervulina, E. tenella, E. necatrix and E. maxima produced a resistance to further infection with the immunizing species. The oocyst output after the second infection, in each case, was lower than that after the initial dose indicating the substantial immunizing effect of the initial infection. The species could be placed in a descending order of immunizing activity as follows: E. maxima, E. acervulina, E. tenella and E. necatrix. A solid immunity to the immunizing species in no way prevented the development of an additional infection, here referred to as `cross-infection', with any of the species studied.

Serum precipitins were produced in infections with all four species, the response to infection with E. necatrix being less marked than to the other species. A first challenge of immune fowls with the immunizing species produced some increase in precipitation in agar whereas a second challenge had no such effect; the significance of this lack of response is discussed. Usually, fowls immunized against one species and then infected with an additional one, produced serum precipitins which reacted only with the antigen of the additional species. But E. tenella immunized fowls, when given an additional infection with E. necatrix, produced precipitins that reacted with antigens of both species. The same was also true when E. necatrix immunized fowls were infected with E. tenella.

  相似文献   
47.
Deletions of 22qll cause DiGeorge sequence (DGS), velo-cardio-facial syndrome (VCFS), conotruncal anomaly face syndrome, and some isolated conotruncal heart anomalies. Demonstration of a 22qll deletion in a patient with manifestations of DGS and Noonan syndrome (NS) has raised the question of whether NS is another of the chromosome 22 microdeletion syndromes. This prompted us to evaluate a cohort of patients with NS for evidence of 22qll deletions. Five of 6 NS propositi studied in our laboratory with marker N25 (D22S75) did not have a 22qll deletion. A 2-month-old infant with several findings suggestive of NS did have a 22qll deletion, suggesting that a small number of 22qll deletion propositi may present with a NS-like picture. However, most cases of NS must have another cause. © 1995 Wiley-Liss, Inc.  相似文献   
48.
Ro (SSA) and La (SSB) antibodies   总被引:2,自引:0,他引:2  
Summary This review traces the historical development of information regarding the Ro (SSA) and La (SSB) autoantibody systems over the past twenty years. Clinical and serologic findings are integrated with fundamental observations in this rapidly expanding area of research. Retrospective analysis of the physicochemical properties of the antigens and the cellular staining characteristics of antibodies to these antigens suggest that SjD and Ro and SSA, as well as SjT and La, SSB, and Ha antigens probably are similar macromolecules. The immunologic identity of Ro with SSA and La with SSB and Ha has been established previously. Antibodies to these antigens are directed against macromolecules containing small RNA nucleotides.Antibodies to the Ro (SSA)-La(SSB) antigen system commonly are detected in the sera of patients with systemic lupus erythematosus and Sjögren's syndrome and appear to be of diagnostic significance. These antibodies occur in up to one quarter of patients with systemic lupus erythematosus (SLE) without the sicca complex, but also in patients with ANA negative SLE who have a prominent photosensitive dermatitis and may have serious renal disease, subacute cutaneous SLE, and in infants and mothers of infants with neonatal SLE. Thus, these antibody systems form a serologic link between many unusual connective tissue diseases and systemic SLE.Antibodies to Ro (SSA)-La(SSB) are associated not only with Sjögren's syndrome occurring alone, but also with Sjögren's syndrome occurring in the setting of other connective tissue diseases including SLE and rheumatoid arthritis. Anemia, leukopenia, and thrombocytopenia, as well as hyperglobulinemia and the presence of rheumatoid factor, cryoglobulins, and antibodies to nuclear antigens are associated significantly with Ro positivity in Sjögren's syndrome patients. There is a striking association of vasculitis in the clinical setting of Sjögren's syndrome with the presence of antibodies to Ro (SSA). In addition to peripheral nerve involvement, unusual central nervous system manifestations as well as myositis occur in these Ro(SSA) positive Sjögren's syndrome patients. Deposition of immunoglobulin and complement within vessel walls of kidney and muscle from Ro positive patients with Sjögren's syndrome suggests a possible role for immune complex deposition in the pathogenesis of the vasculitis.Supported by National Institutes of Health grant 5ROI-AM-25650-03 and Research Career Development Award 5-KO-4-AM-00524-02  相似文献   
49.
Zinc finger protein 462 (ZNF462) is a relatively newly discovered vertebrate specific protein with known critical roles in embryonic development in animal models. Two case reports and a case series study have described the phenotype of 10 individuals with ZNF462 loss of function variants. Herein, we present 14 new individuals with loss of function variants to the previous studies to delineate the syndrome of loss of function in ZNF462. Collectively, these 24 individuals present with recurring phenotypes that define a multiple congenital anomaly syndrome. Most have some form of developmental delay (79%) and a minority has autism spectrum disorder (33%). Characteristic facial features include ptosis (83%), down slanting palpebral fissures (58%), exaggerated Cupid's bow/wide philtrum (54%), and arched eyebrows (50%). Metopic ridging or craniosynostosis was found in a third of study participants and feeding problems in half. Other phenotype characteristics include dysgenesis of the corpus callosum in 25% of individuals, hypotonia in half, and structural heart defects in 21%. Using facial analysis technology, a computer algorithm applying deep learning was able to accurately differentiate individuals with ZNF462 loss of function variants from individuals with Noonan syndrome and healthy controls. In summary, we describe a multiple congenital anomaly syndrome associated with haploinsufficiency of ZNF462 that has distinct clinical characteristics and facial features.  相似文献   
50.
Clinical,hematologic, and immunologic effects of interleukin-10 in humans   总被引:8,自引:0,他引:8  
We conducted a double-blind, placebo-controlled study to investigate the safety, pharmacokinetics, and immunological properties of interleukin-10 (IL-10) administration in healthy humans. Volunteers received a single intravenous bolus injection of recombinant human IL-10 (1, 10, or 25g/kg) or placebo. Cytokine production in whole blood and peripheral blood mononuclear cells (PBMC) was assessed before and 3, 6, 24, and 48 hr after the injection. Peak serum concentrations of IL-10 (15±1.1, 208±20.1, and 505±22.3 ng/ml) occurred after 2–5 min for 1, 10, and 25g/kg IL-10, respectively. The terminal-phase half-life was 3.18 hr. A transient leukocytosis (24–63% above baseline) was observed 6 hr after injection, which coincided with a dose-dependent decrease (12–24%) in neutrophil superoxide generation. There was a marked inhibition (60–95%) of endotoxin-induced IL-6 production from whole blood in each group receiving IL-10. Production of IL-8 in endotoxin-stimulated blood was reduced in the 10g/kg group. In PBMC stimulated with phytohemagglutinin and phorbol ester, there was a decrease (72–87%) in interferon- (IFN) production 6 hr after IL-10 with a return to pre-IL-10 levels after 24 hr. This reduction was only partially associated with a decrease in the number of CD2-bearing cells. We conclude that IL-10 administration into humans is without significant side effects, and a single injection reducesex vivo production of IL-6, IL-8, and IFN.  相似文献   
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