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The laboratory mouse is the model of choice for genetic studies in mammals due to the availability of many genetically defined inbred strains and inbred congenic strains, as well as the ability to study the effects of over-expression (transgenics) or inactivation (knockouts) of a given gene on cells or tissues. During our studies using these technologies to uncover the importance of various genes to apoptosis in the ovary, we observed that the size of the primordial oocyte reserve was affected by mouse strain in the absence of any other genetic manipulation. To determine if genetic modifiers of oocyte endowment truly exist, herein we examined follicle numbers in one outbred (CD-1) and several inbred (129/Sv, DBA/2, C57BL/6, FVB, AKR/J) strains of mice at day 4 (neonatal) and day 42 (young adult) postpartum. In neonatal life, ovaries of AKR/J females had the lowest total number of follicles, whereas 129/Sv females possessed the highest total number of follicles (P < 0.05 for AKR/J versus 129/Sv). There were more primordial follicles in 129/Sv compared with DBA/2 (P < 0.05), C57BL/6 (P < 0.05), FVB (P < 0.05) or AKR/J (P < 0.05) females, and in CD-1 compared with AKR/J (P < 0.05) females. Although no significant strain-dependent differences in primary follicle numbers were noted, C57BL/6 females had the fewest number of small preantral follicles (P < 0.05 versus all other strains). Evaluation of ovaries at 42 days of age revealed the persistence of strain-dependent differences in early follicle growth patterns, although the total numbers of follicles were comparable. Of interest, marked strain-dependent differences in the rate of primordial follicle growth activation, as well as in the rate of follicle loss (atresia), between days 4 and 42 were observed. These results indicate that genetic modifiers play a major role in follicle endowment, development and atresia in the mouse ovary. 相似文献
54.
Modulation by thymus-derived (T) cells of thyroid cell-stimulated prostaglandin E release by human peripheral blood mononuclear cells.
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M Yamamoto N A Takai B Rapoport W E Hinds 《Proceedings of the National Academy of Sciences of the United States of America》1979,76(12):6627-6631
Cultures of plastic-adherent, human peripheral blood mononuclear cells generated prostaglandin E (PGE). Culture of the adherent cells (predominantly monocytes) with human thyroid cells enhanced PGE accumulation in the medium, although to a lesser degree than occurs with unseparated blood mononuclear cells. Recombination of the adherent cells with monocyte-depleted, nonadherent cells restored both basal and thyroid cell-stimulated PGE generation to the levels seen with unseparated cells. Thymus-derived (T) cells, obtained by rosetting with sheep erythrocytes, similarly enhanced both the adherent cell basal PGE production as well as the increased PGE accumulation that occurs in the presence of thyroid cells (50-120% augmentation by the T cells). Significant augmentation of thyroid cell-stimulated PGE release by 10(5) adherent cells occurred with the addition of as few as 5 x 10(4) T cells. Culture medium transfer experiments and separation of cell types during culture by a semipermeable membrane provided evidence against the possibility that the adherent cells were releasing a factor that stimulated T-cell PGE generation or that T cells were releasing a factor that enhanced adherent cell PGE generation. The results suggest instead that this T-cell effect requires direct contact with the adherent cells. These data demonstrate the importance of human T cells in the release by adherent cells of PGE, a mediator of suppressor function by some immune cells. 相似文献
55.
Takai K Nikkuni K Sanada M Shibuya H 《[Rinshō ketsueki] The Japanese journal of clinical hematology》2003,44(7):462-467
A 72-year-old woman was admitted with left cervical lymphadenopathy, high fever, pancytopenia and liver dysfunction. Bone marrow aspiration showed infiltration of large atypical lymphoid cells and hemophagocytic histiocytes, thus suggesting a diagnosis of lymphoma associated hemophagocytic syndrome (LAHS). An abdominal CT scan revealed multiple low-density areas in the liver, and the patient's liver function rapidly deteriorated. Histologically, the cervical biopsy showed lymphoma cell infiltration with prominent necrosis and karyorrhectic debris. The lymphoma cells expressed CD3+, CD4-, CD8+, CD20-, CD56+/-, TIA-1+, granzyme B+, and EBER was positive using in situ hybridization. DNA analysis of the TCR beta and gamma chain gene with the Southern blot showed rearranged bands. These findings were compatible with those of EB-virus associated peripheral T-cell lymphoma. After chemotherapy with the THP-COP regimen, the patient's liver dysfunction improved rapidly, but she died from bacterial peritonitis due to perforation of a recurrent duodenal ulcer. Post-mortem examination of the liver showed multiple irregular massive necroses of the hepatocytes, where no lymphoma cell infiltration was present. Hemophagocytic histiocytosis was remarkable in the bone marrow, spleen, lymph nodes, and liver. Marked elevation of serum levels of cytokines such as TNF-alpha or IFN-gamma suggests that these cytokines played an important role in the pathogenesis of the hepatic cell necrosis. 相似文献
56.
Endo S Sakamoto Y Kobayashi E Nakamura A Takai T 《Proceedings of the National Academy of Sciences of the United States of America》2008,105(38):14515-14520
Priming of cytotoxic T lymphocytes (CTLs) by dendritic cells (DCs) is crucial for elimination of pathogens and malignant cells. To activate CTLs, DCs present antigenic peptide-complexed MHC class I molecules (MHC-I) that will be recognized by the CTLs with T cell receptors and CD8 molecules. Here we show that paired Ig-like receptor (PIR)-B, an MHC-I receptor expressed on antigen-presenting cells, can regulate CTL triggering by blocking the access of CD8 molecules to MHC-I. PIR-B-deficient DCs evoked CTLs more efficiently, leading to accelerated graft and tumor rejection. PIR-B(+) non-DC transfectant cells served as less efficient stimulators and targets for CTLs than PIR-B(-) cells at the effector phase in vitro. On surface plasmon resonance analysis, PIR-B and CD8alpha alpha were revealed to compete in binding to MHC-I. Our results may provide a novel strategy for regulating CTL-mediated immunity and diseases in a sterical manner. 相似文献
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Ushiki T Nikkuni K Yoshida C Shibasaki Y Ishikawa T Masuko M Takai K 《[Rinshō ketsueki] The Japanese journal of clinical hematology》2012,53(1):97-104
A 35-year-old man admitted to the hospital for oral hemorrhage was diagnosed with acute promyelocytic leukemia (APL). Remission from APL was achieved by induction therapy with all-trans retinoic acid (ATRA); the PML/RARA fusion gene was not detected on PCR analysis. Despite complete molecular remission, severe persistent pancytopenia, massive ascites, and renal failure were observed. The liver surface appeared rough and irregular on computed tomographic images. On the basis of the liver biopsy results, we diagnosed his condition as portal hypertension due to autoimmune hepatitis. Indocyanine green test showed good residual function of the liver, and therefore, 2 courses of consolidation therapy were administered; chemotherapy was stopped because of severe pancytopenia due to portal hypertension. Instead of continuing the consolidation therapy, maintenance therapy involving 8 rounds of ATRA monotherapy (45 mg/m(2), days1~14) was initiated. Portal hypertension did not progress further with this maintenance therapy and therefore it was continued. The patient has been in remission from APL ever since, and no relapses have occurred since the past 5 years. These results suggest that ATRA can be used for long-term therapy in such cases. 相似文献
60.
Masanori Kawakami Shigeki Morita Mitsuhiro Sunohara Yosuke Amano Rie Ishikawa Kousuke Watanabe Emi Hamano Nobuya Ohishi Jun Nakajima Yutaka Yatomi Takahide Nagase Masashi Fukayama Daiya Takai 《International journal of clinical and experimental pathology》2013,6(4):598-612
Here, we show that overexpression of fer tyrosine kinase (FER), a non-receptor tyrosine kinase, predicts poor postoperative outcome and might be involved in cancer-cell survival in non-small cell lung cancer (NSCLC). Systematic screening using in silico analyses and quantitative RT-PCR revealed that FER was overexpressed in about 10% of NSCLC patients. Evaluation of FER expression using immunohistochemistry (IHC) on tissue microarrays was consistent with the mRNA level detected using quantitative RT-PCR. In analyses of 135 NSCLC patients who had undergone potential curative resection, we found that FER overexpression detected using IHC had no association with clinicopathological features such as age, sex, smoking history, histological type, disease stage, T factor, N factor, adjuvant chemotherapy history, or EGFR mutation, but was correlated with poor postoperative survival periods. A multivariate Cox regression analysis showed that this prognostic impact was independent of other clinicopathological features. In functional analyses of FER in vitro, FER exhibited a transforming activity, suggesting that it possesses oncogenic functions. We also found that human lung cancer NCI-H661 cells, which exhibited FER-outlier expression, were led to apoptosis by the knockdown of FER using RNA interference. FER overexpression might serve as a prognostic biomarker and be involved in cancer-cell survival in NSCLC. 相似文献