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41.
Masami Yamamoto Hideaki Enzan ° Hiroshi Hara ° Soichi Iijima °° 《Pathology international》1978,28(4):513-521
Findings of perivascular mesenchymal cells and fibroblasts in mice receiving large doses of vitamin A were described. Liver, lung, intestine and skin were investigated by fluorescence and electron microscopy. Marked increase of fluorescence of vitamin A was observed in the sinusoidal wall of the liver, in the alveolar septa of the lungs, in the propria mucosa, submucosa and muscular layer of the intestine and in the dermis of the abdominal skin. Increased fluorescence of these organs corresponded, ultrastructually, to the appearance of numerous fat droplets in Ito cells of the liver, septal cells of the lung and fibroblasts of the intestine and of the skin. All of these cells showed the same morphological features and the same distribution in the tissue, namely in the interstitial connective tissue space. These findings indicate that vitamin A storing cells are distributed widely in the connective tissue of various organs and that perivascular vitamin A storing mesenchymal cells and interstitial fibroblasts are probably of common fibroblastic cell line. 相似文献
42.
Chronic active Epstein-Barr virus (EBV) infection has been recognized as clonal non-neoplastic lymphoproliferative diseases. However, some reports of cases with a multiphenotypic expansion of EBV-infected lymphocytes give rise to questions of how EBV infects multiphenotypic lymphocytes and whether chronic active EBV infection is a truly monoclonal lymphoproliferative disease. We report two patients with chronic active EBV infection who showed expansion of multiphenotypic EBV-infected lymphocytes. EBV DNA was detected in CD4+ and CD8+ T cells and in B cells from pleural fluid of one patient and in T and B cells from a cervical lymph node of the other patient by polymerase chain reaction (PCR). Although real-time PCR showed that there were equally high loads of EBV genomes in CD4+ and CD8+ T cells from the pleural fluid, Southern blot hybridization with terminal repeats of the EBV genome showed a single band of the same molecular weight in three tissue samples from the patient. The results indicated biphenotypic expansions of CD4+ and CD8+ T cells infected with the same clone of EBV. Furthermore, bisulfite PCR analysis showed hypermethylated status in the Cp region in the two patients regardless of their cell populations. There has been a discrepancy between clonality and expansion of multiphenotypic EBV-infected lymphocytes. We speculate that lymphoid progenitor cells that have not differentiated into T and B cell progenitors are infected with EBV, resulting in clonal expansion of EBV-infected multiphenotypic cells. 相似文献
43.
A case of primary localized amyloid tumor of the breast is described. It Is an extremely rare condition and has not been seen in literature in Japan. A 76-year-old woman visited a hospital because of a painless, hard mass of the right breast. A relatively well demarcated, calcified mass was excised under clinical diagnosis of fibroadenoma. Histologically, massive eoslnophilic amorphous material was deposited in breast stroma. It was stained red-orange by Congo red and displayed apple-green birefringence under polarized light. The staining persisted after incubation with KMnO4 and immunolabeling by immunoglobulin x-light chain antlserum, consistent with the amyloid of AL (Ax) type. Osseous metaplasia with bone marrow cavity, foreign body type giant cells in response to amyloid, and scattered plasma cell infiltration were also recognized. Osseous metaplasia in the breast amyloid tumor has been reported in only one case before. To date, the patient has not developed any clinical or laboratory evidence of systemic amyloidosis or multiple myeloma. 相似文献
44.
Ikegaya H Iwase H Zheng HY Nakajima M Sakurada K Takatori T Fukayama M Kitamura T Yogo Y 《Journal of virological methods》2005,126(1-2):37-43
Recently genotyping of JC virus (JCV) DNA in renal tissue was reported to be useful to identify the geographic origin of unidentified cadavers. In the above study, autopsied tissue samples without storage or stored in a frozen state were used. This study examined JCV DNA sequence modifications caused by formalin-fixation, in an attempt to elucidate whether formalin-fixed, paraffin-embedded tissue samples can also be used to determine the genotypes of JCV DNA in the kidney. In four cases, a 610 bp typing region of the JCV genome was PCR-amplified from renal tissues stored for 1 year in three different states: frozen at -80 degrees C [Amaker, B.H., Chandler, F.W., Huey, L.O., Colwell, R.M., 1997. Molecular detection of JC virus in embalmed, formalin-fixed, paraffin-embedded brain tissue. J. Forensic Sci., 1157-1159], formalin-fixed, paraffin-embedded [Ault, G.S., Stoner, G.L., 1992. Two major types of JC virus defined in progressive multifocal leukoencephalopathy brain by early and late coding region DNA sequences. J. Gen. Virol. 73, 2669-2678], and soaked in 5% formalin [Baksh, F.K., Finkelstein, S.D., Swalskey, P.A., Stoner, G.L., Ryschkewitsch, C.F., Randhawa, P.R., 2001. Molecular genotyping of BK and JC virus in human polyomavirus-associated interstitial nephritis after renal transplantation. Am. J. Kidney Dis. 38 (2), 354-365]. The amplified fragments were cloned, and the resultant clones were sequenced. In frozen samples, single sequences ('original' sequences) were detected in all cases. In formalin-fixed, paraffin-embedded samples, not only the original sequences but also those with 1-6 base substitutions were detected. From formalin-soaked samples, the original sequences and those with 1-5 and 10-13 substitutions were detected. The genotyping of JCV DNA was not hampered by the presence of 1-6 substitutions, but a shift in JCV genotypes was observed in sequences with 10-13 substitutions. Thus, it was concluded that the genotypes of JCV DNA in the kidney can be determined only with specimens stored in a frozen state or formalin-fixed for a short time. 相似文献
45.
Takashi Minase Minoru Ogasawaea Takanori Kikuchi Hideaki Hirai Akira Suzuki Chieko Nishio Katsuhiro Ogawa Kokichi Kikuchi Michio Mori 《Pathology international》1985,35(3):711-721
A case of lymphomatoid granulomatosis (LYG) involving the lungs, skin, stomach, and possibly the left kidney in a 60-year-old man is presented. The infiltrates in the lungs, stomach, and skin showed a polymorphic appearance, and consisted predominantly of lymphocytes of mature and blastic form and of a few neutrophils, plasma cells, and histiocytes. Most lymphoid cells showed irregularly shaped nuclei and clustered dense bodies, characteristics indicative of T lymphocytes. An immunohistochemical study confirmed the T cell origin of the lymphocytes; i.e. they were positive for Leu-1, Leu-3a and la-like antigens but negative for Leu-2a antigen and the antibodies against light chains. The homogeniety of the major population of infiltrates in LYG indicates that at least some forms of LYG may be neoplastic or pre-neoplastic lymphocytic disorders which may ultimately progress to malignant lymphoma. ACTA PATHOL. JPN. 35 : 711–721, 1985. 相似文献
46.
Masayuki Nakayama Masashi Bando Tatsuya Hosono Hideaki Yamasawa Shoji Ohno Yukihiko Sugiyama 《Arerugī》2007,56(11):1384-1389
BACKGROUND: Our aim is to evaluate the significance of DLST by Shosaikoto. METHODS: We clinically evaluated 3 cases of drug-induced pneumonia assumed to be caused by Shosaikoto, and we performed DLST of Shosaikoto for healthy controls, and compared the data with drug-induced pneumonia cases of Shosaikoto. RESULTS: As clinical characteristics of 3 cases, 2 cases were positive for hepatitis C virus antibody, and 1 case was positive for DLST of Shosaikoto. The observed chest high-resolution CT (HRCT) findings showed hypersensitivity pneumonia (HP) pattern in all 3 cases. Prognosis was good in all 3 cases. DLST of Shosaikoto was positive in 27.5% of healthy controls. Stimulation index (S.I.) of DLST in drug-induced pneumonia cases increased depending on drug dilution density, compared to that of healthy controls. CONCLUSION: DLST of Shosaikoto showed high false-positive rate. However, we may be able to distinguish the true-positive cases with the false-positive cases by comparing the S.I. of DLST according to drug dilution density. 相似文献
47.
Atsuo Murata Hitoshi Toda Ken -Ichi Uda Hirohito Hayashida Takeshi Kato Hidewaki Nakagawa Shigekazu Yokoyama Hideaki Morishita Toru Yamakawa Jiro Hirose Takesada Mori Nariaki Matsuura 《Inflammation》1994,18(4):337-347
Severe inflammatory responses after major surgeries, trauma, and infection develop multiple organ dysfunction. In the mechanisms of the pathogenesis of these responses, activated neutrophils are thought to be important in terms of their ability to produce various kinds of proteinases, which can degrade various proteins constructing human tissues. Among their proteinases, neutrophil elastase is the strongest serine proteinase secreted from activated neutrophils. Thus, we examined in this study the inhibitory effect and therapeutic efficacy of newly produced recombinant human Kunitz-type proteinase inhibitor (R-020), which coded the second domain of human urinary trypsin inhibitor. R-020 was effective in significantly improving the survival rate after induction of the rat lethal peritonitis model (cecal ligation and punctureinduced septic shock model). We suggest that various serine proteinases are implicated in the pathogenesis of neutrophil-related multiple organ failure and that recombinant human Kunitz-type proteinase inhibitor might be effective in the treatment of these kinds of organ dysfunction. 相似文献
48.
Monocarboxylate transporter 1 (MCT1) plays a direct role in short-chain fatty acids absorption in caprine rumen 总被引:2,自引:0,他引:2
Doaa Kirat Junji Masuoka Hideaki Hayashi Hidetomo Iwano Hiroshi Yokota Hiroyuki Taniyama Seiyu Kato 《The Journal of physiology》2006,576(2):635-647
Despite the importance of short-chain fatty acids (SCFA) in maintaining the ruminant physiology, the mechanism of SCFA absorption is still not fully studied. The goal of this study was to elucidate the possible involvement of monocarboxylate transporter 1 (MCT1) in the mechanism of SCFA transport in the caprine rumen, and to delineate the precise cellular localization and the level of MCT1 protein along the entire caprine gastrointestinal tract. RT-PCR revealed the presence of mRNA encoding for MCT1 in all regions of the caprine gastrointestinal tract. Quantitative Western blot analysis showed that the level of MCT1 protein was in the order of rumen ≥ reticulum > omasum > caecum > proximal colon > distal colon > abomasum > small intestine. Immunohistochemistry and immunofluorescence confocal analyses revealed widespread immunoreactive positivities for MCT1 in the caprine stomach and large intestine. Amongst the stratified squamous epithelial cells of the forestomach, MCT1 was predominantly expressed on the cell boundaries of the stratum basale and stratum spinosum. Double-immunofluorescence confocal laser-scanning microscopy confirmed the co-localization of MCT1 with its ancillary protein, CD147 in the caprine gastrointestinal tract. In vivo and in vitro functional studies, under the influence of the MCT1 inhibitors, p -chloromercuribenzoate (pCMB) and p -chloromercuribenzoic acid (pCMBA), demonstrated significant inhibitory effect on acetate and propionate transport in the rumen. This study provides evidence, for the first time in ruminants, that MCT1 has a direct role in the transepithelial transport and efflux of the SCFA across the stratum spinosum and stratum basale of the forestomach toward the blood side. 相似文献
49.
Kiyonori Miura Hideaki Masuzaki Tadayuki Ishimaru Norio Niikawa Y. Jinno 《Journal of human genetics》1998,43(4):283-284
We found a HhaI/BstUI polymorphism in the 3′ untranslated region of a novel gene which was localized to 11p15.5. This region is one of prominent
imprinting domains and contains multiple imprinted genes, such as H19, IGF2 , KVLQT1, and p57
KIP2
, which suggests that regional factors might contribute to the imprinting.
This polymorphism will be useful in the allelic analysis of expression and methylation of the novel gene.
Received: July 24, 1998 / Accepted: July 29, 1998 相似文献
50.
IL-1 is required for allergen-specific Th2 cell activation and the development of airway hypersensitivity response 总被引:1,自引:0,他引:1
Nakae S Komiyama Y Yokoyama H Nambu A Umeda M Iwase M Homma I Sudo K Horai R Asano M Iwakura Y 《International immunology》2003,15(4):483-490
IL-1 is a pro-inflammatory cytokine consisted of two molecular species, IL-1alpha and IL-1beta, and the IL-1 receptor antagonist (IL-1Ra) is a natural inhibitor of both molecules. Although it is suggested that IL-1 potentiates immune responses mediated by T(h)2 cells, the role of IL-1 in asthma still remains unclear. In this study, we demonstrate that the ovalbumin (OVA)-induced airway hypersensitivity response (AHR) in IL-1alpha/beta-deficient (IL-1alpha/beta(-/-)) mice was significantly reduced from the levels seen in wild-type mice, whereas the responses seen in IL-1Ra(-/-) mice were profoundly exacerbated, suggesting that IL-1 is required for T(h)2 cell activation during AHR. OVA-specific T cell proliferation, IL-4 and IL-5 production by T cells, and IgG1 and IgE production by B cells in IL-1alpha/beta(-/-) mice were markedly reduced compared with these responses in wild-type mice; such responses were enhanced in IL-1Ra(-/-) mice. Using IL-1alpha(-/-) and IL-1beta(-/-) mice, we determined that both IL-1alpha and IL-1beta are involved in this reaction. Both IgG1 and IgE levels were reduced in IL-1beta(-/-) mice, while only IgE levels were affected in IL-1alpha(-/-) mice, indicating a functional difference between IL-1alpha and IL-1beta. These observations indicate that IL-1 plays important roles in the development of AHR. 相似文献