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221.
L. A. Basharova L. A. Vetrilé V. A. Evseev E. A. Gromova N. V. Bobkova L. A. Plakzhinas L. E. Fast 《Neuroscience and behavioral physiology》1990,20(2):109-113
The influence of induction of antibodies to the neuromediator serotonin in the case of active immunization of animals with a conjugate serotonin-protein antigen on the distribution of biogenic amines in the brain and on behavioral responses was investigated in experiments on rats. It was shown that active immunization of rats with a serotonin-protein conjugate leads to a decrease in serotonin, its metabolite 5-hydroxyindole-3-acetic acid, as well as dopamine in certain brain structures. Against a background of induction of antibodies to serotonin, the horizontal motor activity of the animals is decreased.Translated from Fiziologicheskii Zhurnal SSSR imeni I. M. Sechenova, Vol. 74, No. 10, pp. 1367–1372, October, 1988. 相似文献
222.
M. M. F. J. Tinnemans M.-H. J. H. Lenders F. C. S. Ramaekers B. Schutte G. P. M. ten Velde S. S. Wagenaar G. H. Blijham 《Virchows Archiv : an international journal of pathology》1995,427(3):295-301
In a series of 44 bronchial biopsies from patients suspected of having endobronchial lung carcinoma, the validity of proliferating cell nuclear antigen (PCNA) and Ki67 antigen as proliferative indicators was evaluated in ethanol fixed, paraffin embedded tissue. The percentages of cells positive for these markers were compared to the in vivo bromodeoxyuridine (BrdU) labelling index. A good correlation was found between PCNA immunoreactivity and BrdU labelling index, while Ki67-antigen expression showed a significant relation with BrdU labelling index and with PCNA expression. All three parameters showed a trend towards similar values for the individual cases. Based on the fact that Ki67 antigen is expressed in all cycling cells, whereas replicon-associated PCNA and BrdU only reflect the S-phase fraction, the differences between Ki67-antigen scores on the one hand and BrdU and PCNA scores on the other were smaller than expected. In order to determine the degree of concordance between immunohistochemically and flow cytometrically detected proliferation variables, BrdU incorporation was measured using both methods in duplicate bronchial specimens. Discrepancies in labelling indices were observed predominantly in DNA diploid samples, with consistently lower values in the flow cytometrically analysed specimens. In tumour specimens with an aneuploid DNA content, flow cytometric determination of proliferative activity yielded results similar to those obtained by tissue section examination. We conclude that the scores for PCNA and Ki67 antigen, immunohistochemically detected in ethanol fixed, paraffin embedded tissue reflect functional proliferative activity. 相似文献
223.
Selective pairwise interactions between CD3 chains and the clonotypic T cell antigen receptor (TCR)-α, -β chains has recently been established. In this study, the region of interaction between clonotypic and CD3 chains involved with assembly was examined. To determine the site of protein interaction a variety of genetically altered TCR chains were constructed. These included: truncated proteins, lacking transmembrane and or cytosolic domains; chimeric proteins, in which extracellular, transmembrane or cytosolic domains were replaced with similar domains derived from either the Tac antigen or CD4; and point mutagenized TCR chains. COS-1 cells were transfected with cDNA, metabolically labeled, and immunoprecipitates analyzed using non-equilibrium pH gel electrophoresis (NEPHGE)-SDS/PAGE. The results demonstrated that assembly between TCR-α and TCR-β chains occurred at the extracellular level. Assembly of the TCR-α chain with CD3-δ, and CD3-ε was localized to an eight-amino acid motif within the transmembrane domain of TCR-α. Site-specific mutations of the TCR-α charged residues within this motif ( arginine, lysine) to leucine and similar point mutations of the transmembrane CD3-ε and CD3-δ charge groups resulted in the abrogation of assembly. In contast, TCR-β and CD3-ε binary complexes interacted via their extracellular domain. Analogous to TCR-α, the site of TCR-β and CD3-δ assembly was at the transmembrane region. Despite multiple genetic manipulations on CD3-γ and ζ; these proteins failed to assemble with TCR-α. Similarly, there was no interaction between TCR-β and ζ. These findings when coupled with the information on pairwise interactions and formation of higher order subcomplexes extend our model for the structure of the TCR complex. 相似文献
224.
Mary K. Kennedy Kendall M. Mohler Kurt D. Shanebeck Peter R. Baum Kathleen S. Picha Carol A. Otten-Evans Charles A. Janeway Kenneth H. Grabstein 《European journal of immunology》1994,24(1):116-123
T cell-dependent regulation of B cell growth and differentiation involves an interaction between CD40, a B cell surface molecule, and the CD40 ligand (CD40L) which is expressed on activated CD4+ T cells. In the current study, we show that recombinant membrane-bound murine CD40L induces B cells to express costimulatory function for the proliferation of CD4+ Tcells. CD40L- or lipopolysaccharide (LPS)-activated, but not control-cultured B cells were strong costimulators of anti-CD3 or alloantigen-dependent T cell responses. The molecular interactions responsible for the increased costimulatory functions were examined by analyzing the activated B cells for changes in the expression of two costimulatory molecules, B7 and heat-stable antigen (HSA), as well as by the use of antagonists of B7 and HSA (CTLA4.Fc and 20C9, respectively). The expression of both B7 and HSA was enhanced on B cells activated with LPS. As observed in previous studies, the costimulatory activity of the LPS-activated B cells was dependent on both B7 and HSA and was completely inhibited in the presence of a combination of CTLA4.Fc and 20C9. In contrast, activation of B cells with CD40L induced the expression of B7 but did not enhance the expression of HSA. In addition the costimulatory activity of the CD40L-activated B cells was partially, but not completely, inhibited by the combination of CTLA4.Fc and 20C9. These results demonstrate that CD40L regulates costimulatory function of B cells in part by inducing the expression of B7 and suggest that CD40L-activated B cells express an additional costimulatory activity that is not associated with LPS-activated B cells. 相似文献
225.
Metastatic prostatic carcinoma presenting as left-sided cervical lymphadenopathy: a series of 11 cases 总被引:2,自引:0,他引:2
Eleven cases of metastatic prostatic carcinoma in cervical lymph nodes as a primary presenting sign were identified in a survey of 250 cervical lymph node biopsies from men. The diagnosis was clinically unsuspected in all cases. All occurred on the left side of the neck. These 11 cases represented 11% of all metastatic carcinomas in the neck and 20% of those with left-sided involvement. The diagnosis was readily confirmed by immunostaining for prostate specific antigen and prostate specific acid phosphatase. Six patients are alive and well at an average of 25.8 months and five others survived for an average of 34.4 months, the combined survival being 29.7 months. This contrasts with the dismal fate of patients with metastatic adenocarcinoma from other sites who all died at an average of 2 months from diagnosis. Prostatic carcinoma should always be considered in the differential diagnosis of metastatic carcinoma in cervical lymph nodes in elderly men, as appropriate treatment results in worthwhile prolongation of life. 相似文献
226.
H Kanagawa E Takai F Tsuda A Machida M Kojima A Ishijima T Tanaka H Okamoto Y Miyakawa M Mayumi 《Journal of medical virology》1992,37(4):288-293
Of sera from 1,878 Japanese blood donors who carried hepatitis B surface antigen (HBsAg), 420 were subtyped as adw (22.4%) and 1,443 as adr (76.8%); only 15 (0.8%) contained HBsAg of subtype ayw or ayr. Sera with HBsAg/adr had higher HBsAg titres than those with HBsAg/adw (geometric mean of haemagglutination titre: 10.1 +/- 2.4 vs. 9.7 +/- 2.4, p less than 0.01), and a higher prevalence of hepatitis B e antigen (24% vs. 13%, p less than 0.001). Carriers of HBsAg/adr progressively predominated over those of HBsAg/adw with increasing age. Of sera from 1,863 carriers of HBsAg/adw or HBsAg/adr, 182 (9.8%) contained HBsAg particles with both subtypic determinants in the w/r allele. The presence of w and r determinants on the same particles was ascertained by sandwiching them between monoclonal antibody with the specificity for w and that with the specificity for r. HBsAg particles of compound subtype (adwr) were found more often in sera with hepatitis B e antigen than those without it (145/403 [36.0%] vs. 37/1,460 [2.5%], p less than 0.001). Sera with HBsAg/adwr particles had HBsAg titres higher than those without them (12.4 +/- 1.9 vs. 9.7 +/- 2.3, p less than 0.001). HBsAg/adwr particles arise from phenotypic mixing of the S-gene product of wild-type virus and that of mutants with point mutations for subtypic changes. The results obtained indicated that HBV strains of subtype adr have a higher replicative activity than those of adw, and suggested that mutations in the S gene for subtypic changes would be associated with an active replication of hepatitis B virus. 相似文献
227.
Petros M Pavlopoulos Anastasia E Konstantinidou Emmanuel Agapitos Panagiotis Davaris 《Clinical genetics》1998,54(6):512-516
Roberts syndrome (RS) is a rare autosomal recessive disorder characterized primarily by symmetric reduction anomalies of all limbs, growth retardation and craniofacial abnormalities. Most RS patients are reported to present a typical abnormality of their constitutive heterochromatin, accompanied by abnormal cytological growth characteristics. We present an extremely severe case of an RS fetus, karyotypically documented, with a clinical presentation including growth deficiency, tetraphocomelia, frontal meningocele, craniofacial abnormalities and penile enlargement with hypospadias. Nuclear morphometrical analysis in tissues of various organs revealed a reduced nuclear size in RS as compared to normal controls, and statistically significant differences in morphometric parameters related to the nuclear shape. Immunohistochemical study of the same organs showed a reduced expression of proliferating cell nuclear antigen in the presented case, thus indicating a decreased cell proliferation rate in RS. Our results reconfirm previously reported findings in cultured fibroblasts of RS cases, thereby reinforcing on a histologic level, the hypothesis that reduced cell proliferation may be involved in the growth retardation and the reduction abnormalities observed in RS. 相似文献
228.
Enhanced polymer one-step staining (EPOS) is a novel, highly sensitive one-step immunostaining method. This simple and rapid technlque was applied to intra-operattve frozen diagnosis. The markers of choice were proliferating cell nuclear anmen (PCNA) and Ki-67 antigen. These cell prollferation markers were both identifiable in fresh frozen see tions of the human tonsil In approximately 7 min. The suitable staining sequences are as follows. Frozen sections prepared using 3-aminopropyitimethoxysilane-cpated glass slides are immediately fixed, without air drying, for 15s in a mixture of 50% formalin and 50% methanol for PCNA, and in 10% formalln for Ki-67 antigen. After a brief rinse in phosphate-buffered saline (PSS), sections are incubated with the EPOS antibody for 3 min, followed by PBS rinse for 1 min. The peroxidase activity is visualized in diaminobenzidine-H2 O2 solution containing 10mmol/L imidazole for 2 min. After a light rinse in tap water, the nuclei are briefly counterstained with 5% methyl green. When necessary, endogenous peroxi-dase blockage in 1% periodic acid solution for 1 min is added before the EPOS antibody incubation. This procedure is applicable to frozen sections of gastric cancers, malignant lymphomas, and brain, liver and peritoneal lesions in which differential diagnosis between benignancy and malignancy was required. 相似文献
229.
重型乙型病毒性肝炎肝组织内T淋巴细胞亚群的观察 总被引:1,自引:0,他引:1
本文用抗CD_3,CD_4,CD_8McAb和ABC法检测21例重型乙肝患者肝大片,亚大片坏死区炎性浸润细胞中的T细胞亚群,CD_3~+细胞>70%,其中主要为CD_8~+细胞,CD_4~+细胞减少,CD_4~+/CD_8~+比值显著下降,与急黄肝和慢活肝比较差异显著。相反,非HBV感染性肝病患者非T细胞和CD_4~+细胞增加,CD_4~+/CD_8~+比值>1。提示重肝时T细胞可能参与了肝损伤,CD_8细胞亚群可能是介导肝细胞坏死的重要因素之一。还观察到相当数量的淋巴细胞和肝细胞HLA—DR抗原阳性,淋巴细胞与膜型HBAg(+)肝细胞密切接触。 相似文献
230.
Reverse enzyme-linked immunospot assay (RELISPOT) for the detection of cells secreting immunoreactive substances 总被引:9,自引:0,他引:9
C C Czerkinsky A Tarkowski L A Nilsson O Ouchterlony H Nygren C Gretzer 《Journal of immunological methods》1984,72(2):489-496
A reverse modification of the recently described enzyme-linked immunospot assay (ELISPOT), based on localized enzyme-substrate reactions in gel, is described for the enumeration of antigen-secreting cells using petri dishes coated with specific antibodies. As a model the detection of mouse and human immunoglobulin-secreting cells has been evaluated. Simple and sensitive, this new method, termed RELISPOT, can be adapted for the quantitation of secreted antigen thus providing additional information on the metabolic state of the population of cells tested. 相似文献