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101.
Hayashi M Ueda Y Yamaguchi T Sohma R Shibazaki M Ohkura T Inaba N 《American journal of reproductive immunology (New York, N.Y. : 1989)》2005,53(3):113-119
PROBLEM: Tumor necrosis factor-alpha (TNF-alpha) is present in human placental and uterine cells at the early and late stages of gestation and promotes the regulation of trophoblast growth and invasion. We evaluated whether TNF-alpha levels in the placenta and blood of pre-eclamptic women differed from those with normal pregnancies. METHOD OF STUDY: The subjects were 39 pregnant women carrying single fetuses (21 normal-pregnant and 18 pre-eclamptic patients). Their average gestational age at entry was 38-39 weeks. Peripheral blood was collected before the onset of labor and separated serum was stored at -20 degrees C. A tissue segment of the placenta was cut and frozen in liquid nitrogen immediately after delivery at -80 degrees C. The frozen placental tissue was added to phosphate-buffered saline. The tissue was fully homogenized and centrifuged. Separated supernatant was stored at -80 degrees C. TNF-alpha levels in separated serum and TNF-alpha and total protein (TP) levels in separated supernatant were measured. The presence of TNF-alpha in the placenta was evaluated by immunohistochemistry in five pre-eclamptic and five normal-pregnant patients. RESULTS: Serum TNF-alpha levels were higher in pre-eclampsia than in normal pregnancies. However, TNF-alpha/TP levels in the placenta did not differ significantly between the two groups. As for TNF-alpha immunostaining of trophoblastic cells in the placenta, it was weak in three and moderate in two of the normal pregnancies, while it was absent in two, weak in one, and moderate in two in the pre-eclampsia group. CONCLUSIONS: We demonstrated no significant increase in TNF-alpha/TP levels in the placenta in pre-eclampsia despite a significant increase in serum TNF-alpha levels. There was no strong immunostaining for TNF-alpha detected by immunohistochemistry in the pre-eclampsia group. These findings suggest that TNF-alpha in the placenta is not a key cytokine to interfere with normal trophoblast invasion into the myometrium in pre-eclampsia, and that sources other than the placenta may contribute to the elevated levels of TNF-alpha found in the circulation of pre-eclamptic patients. 相似文献
102.
Md. Iqbal Hossain Chowdhury Yoshio Koyanagi Michihiko Suzuki Susumu Kobayashi Kazuhito Yamaguchi Naoki Yamamoto 《Virus genes》1992,6(1):63-78
Syncytia or multinucleated giant-cell formation is one of the major cytopathic effects induced by human immunodeficiency virus (HIV) infection. Cell fusion results from the strong interaction of CD4 molecules on the surface of the uninfected T cells and gp120, an external envelope glycoprotein of HIV on the infected T cells. We studied the production of HIV in fusion cells between MOLT-4 and virus-infected MOLT-4/HIV cells and found that HIV production was enhanced up to three- to fivefold, which showed a good correlation with the appearance and extent of syncytia formation. Blocking the fusion by monoclonal antibody against a binding epitope of CD4 molecule to gp120 decreased the HIV production significantly. Enhancement of HIV production was observed by more than five-fold in comparison with chronically infected cells, which were fusion free 20 hr postcocultivation. Electron microscopic observation also showed the presence of abundant HIV particles inside the fused cells and on the outer surface. AZT blocked the HIV augmentation of fused cells in coculture completely. Southern blot analysis revealed that both integrated and unintegrated HIV DNA were highly accumulated in fusion cells, as compared with fusion-free MOLT-4/HIV cells. Among unintegrated DNA, circular and linear DNA were accumulated to a similar degree. Northern blot hybridization showed that rapid enhancement of all three species of HIV-specific RNA containing genomic (9.2 kb) and subgenomic (4.3 and 1.9 kb) RNAs were found 20 hr postinfection in fusion cells. These data suggest that syncytia formation is an extremely active infection process of HIV, by which multiple rounds of reinfection might take place. 相似文献
103.
M Yamaguchi K Hirai Y Morita T Takaishi K Ohta S Suzuki K Motoyoshi O Kawanami K Ito 《International archives of allergy and immunology》1992,97(4):322-329
Human basophils were purified from normal peripheral blood, using density gradient followed by negative panning selection. We tested the effects of hemopoietic growth factors on the survival of these basophils in vitro. In the absence of exogenous factors, basophils (purity greater than 90%) decreased in number rapidly. At day 7 only 11% of the cells remained alive in cultures; less than 1% of cells survived at day 14. Interleukin (IL)-3 maintained numbers of viable cells; cell viability was 67% at day 7 and 45% at day 14. Granulocyte-macrophage (GM)-colony-stimulating factor (CSF) exhibited slight effect on the survival; 33% of cells remained at day 7. Other growth factors including granulocyte (G)-CSF, macrophage (M)-CSF, and IL-4 had no significant effect on the survival of basophils at all. Morphological and functional characterization of cells maintained by IL-3 revealed that they belonged to the basophil lineage. These observations indicate that normal basophils possess functional receptors for IL-3 and GM-CSF and that both factors modulate immediate- and delayed-type hypersensitivity reactions by prolonging the life span of basophils. 相似文献
104.
Atsuo Ogura Toshihiko Asano Junichiro Matsuda Minako Koura Masaro Nakagawa Hiroshi Kawaguchi Yutaka Yamaguchi 《Virchows Archiv : an international journal of pathology》1990,417(3):223-228
Summary Glomerular lesions in hereditary nephrotic mice (ICGN strain) were investigated by electron microscopy. The glomeruli of unaffected animals, which appeared normal by light microscopy, had developed an ultrastructural change in the glomerular capillary basement membrane (GCBM). There was a partial thickening of the GCBM with bilaminar splitting of the lamina densa and an electron-dense fibrillar material exhibiting cross-striations. In affected animals, light microscopy revealed a marked thickening of GCBM and an increase of mesangial matrix without cellular proliferaton. By electron microscopy, multilaminar splitting of the lamina densa in the thickened GCBMs and fusion of the epithelial foot processes were observed. In some severely affected animals, immune complex deposition was found in GCBM, but little if any was observed in other animals. In the end, the glomeruli were globally sclerosed. Our findings suggest that initial structural abnormalities in GCBM may play an important role in the onset and development of the disease, though subsequent events such as immune complex deposition would modify the disease. 相似文献
105.
Okubo Y Seno T Yamaguchi H Miyata Y Green CA Daniels GL 《Immunohematology / American Red Cross》1993,9(4):105-108
The first Japanese En(a-) individual (T.N.) was found by screening red cells from 250,000 Japanese blood donors with monoclonal anti-Ena. His serum contained no atypical antibodies and his partial red cell phenotype was M-N-S+s-, although a trypsin- resistant N antigen was detected. His red cells were En(a-) and Wr(b-), as determined by various human and mouse monoclonal antibodies. The absence of glycophorin A (GPA) and the presence of apparently normal glycophorin B (GPB) were demonstrated by immunoblotting with antibodies to the extracellular and cytoplasmic domain of GPA and to epitopes common to GPA and GPB. Sialic acid levels of T.N.'s intact red cells were substantially lower than those of control MN cells. Serologic tests suggested that both of T.N.'s parents were heterozygous for a recessive GPA deficiency gene. 相似文献
106.
Zheng-Lin Jiang Hisao Yamaguchi Akira Takahashi Shingo Tanabe Noboru Utsuyama Toshitaka Ikehara Keiko Hosokawa Hiroyuki Tanaka Yohsuke Kinouchi Hiroshi Miyamoto 《European journal of applied physiology》1995,70(3):234-239
Cerebral blood volume flow and flow velocity have been reported to increase during dynamic exercise, but whether the two increase in parallel and whether both increases occur as functions of exercise intensity remain unsettled. In this study, blood flow velocity in the common carotid artery was measured using the Doppler ultrasound method in eight healthy male students during graded treadmill exercise. The exercise consisted of stepwise progressive increases and decreases in exercise intensity. The peak intensity corresponded to approximately 85% of maximal oxygen consumption. During this exercise, the heart rate (f
c), mean blood pressure (BP) in the brachial artery and mean blood flow velocity (cc) in the common carotid artery increased as functions of exercise intensity. At the peak exercise intensity, (f
c), BP and cc increased by 134.5%, 20.5% and 51.8% over the control levels before exercise (P < 0.01), respectively. The resistance index (RI) and pulsatility index (PI) were determined from the velocity profile and were expected to reflect the distal cerebral blood flow resistance. The RI and PI increased during the graded exercise, but tended to decrease at the highest levels of exercise intensity. As cc increased with increases in exercise intensity it would be expected that cerebral blood flow would also increase at these higher intensities. It is also suggested that blood flow velocity in the cerebral artery does not proportionately reflect the cerebral blood flow during dynamic exercise, since the cerebral blood flow resistance changes. 相似文献
107.
108.
T Toge K Kuroi H Kuninobu Y Yamaguchi Y Kegoya N Baba T Hattori 《Clinical and experimental immunology》1988,74(3):409-412
In order to analyse the role of the spleen on immunosuppression of gastric cancer, T cell phenotypes in the spleen cells (SC) were investigated by two colour fluorescence flow cytometry, with reference to their suppressor cell activity. Suppressor T cell phenotypes of CD4+2H4+ cells (suppressor/inducer T cells) and CD8+CD11+ (suppressor T cells) were distributed predominantly in SCs from patients with gastric cancer, while they were distributed scarcely in those with liver cirrhosis. Moreover, CD4+2H4+ cells and CD8+CD11+ cells were found predominantly in SCs and splenic vein lymphocytes (SVL) respectively. Among SCs, a significantly higher proportion of CD4+2H4+ cells was found in the recirculating SCs, but fewer were found in the residual SCs. Higher activity of Concanavalin-A induced suppressor cells was found in the former and that of spontaneously activated suppressor cells was found in the latter. These results suggest the suppressor precursor and suppressor/inducer T cells might distribute predominantly in the cells recirculating from the spleen, and that suppressor cells might be matured during the migration from the spleen. 相似文献
109.
Four hundred and sixty-five male and 159 female consecutive autopsy cases of lung cancer, autopsied over the 27 years from 1958 to 1984, were analysed and were compared with other materials and mortality statistics, including statistics from other countries. Malignant tumor autopsy cases are gradually increasing and now comprise more than 60% of total autopsy cases. The percentage of lung cancer cases among all autopsy cases was 7% in males and 4% in females. The percentage of lung cancer in autopsies of patients with malignancies was about 13% for males and 9% for females. The most frequent fatal malignant tumors were gastric cancer, lung cancer, and leukemia. The relative incidence of gastric cancer was decreasing, while that of lung cancer was increasing. In the distribution of the histological types of lung cancer, adenocarcinomas were the most frequent types in both sexes. As has been noted in mortality statistics, we noticed a gradual shift in the peak age of lung cancer autopsy cases towards older patients. During the period under study, the peak shifted from patients in their sixties to patient in their seventies; this was true for most of the major histological types in both sexes. The male/female ratio of all lung cancer cases was 2.9, which was much lower than the ratio found in the United States and Europe, and very similar to the ratio of the mortality rates in Japan and other Asian countries. It was pointed out that the male/female ratios by age-group in each country is a very good reflection of the histological distribution. 相似文献
110.