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21.
Kazunori Nagai Yoshihiko Sugiyama Tsuyoshi Hosaka Hikoichiro Takaya 《Pathology international》1973,23(1):59-73
Five autopsy cases of thrombotic microangiopathy, including 3 cases associated with acute promyelocytic leukaemia, were examined macroscopically, light-and electronmicroscopically.
The so-called hyaline thrombi In thrombotic microangiopathy were composed of fibrin and its degenerative products. Thrombocytes and other blood cells were not seen in the thrombi.
At the site of the formation of a thrombus, there was no conspicuous change in the walls of the capillaries and arterioles. It was considered, therefore, that the intravascular deposition of fibrin was the primary event in the development of thrombotic microangiopathy.
In regard to the distribution and morphologic findings, there was no basic difference between the microthrombi in cases associated with acute promyelocytic leukaemia and those without it.
The bone marrow and some other organs in cases of thrombotic microangiopathy associated with acute promyelocytic leukaemia macroscopically revealed a green colour. Many thrombi composed of leukaemic cells and fibrin were found in the pulmonary arteries of these cases. Furthermore, prominent erythrophagocytosis in the bone marrow and lymph nodes was a common finding in these cases. 相似文献
The so-called hyaline thrombi In thrombotic microangiopathy were composed of fibrin and its degenerative products. Thrombocytes and other blood cells were not seen in the thrombi.
At the site of the formation of a thrombus, there was no conspicuous change in the walls of the capillaries and arterioles. It was considered, therefore, that the intravascular deposition of fibrin was the primary event in the development of thrombotic microangiopathy.
In regard to the distribution and morphologic findings, there was no basic difference between the microthrombi in cases associated with acute promyelocytic leukaemia and those without it.
The bone marrow and some other organs in cases of thrombotic microangiopathy associated with acute promyelocytic leukaemia macroscopically revealed a green colour. Many thrombi composed of leukaemic cells and fibrin were found in the pulmonary arteries of these cases. Furthermore, prominent erythrophagocytosis in the bone marrow and lymph nodes was a common finding in these cases. 相似文献
22.
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
23.
Yoshihiko Takahashi Yuichi Takiguchi Takayuki Kuriyama Tadaaki Miyamoto 《Clinical & experimental metastasis》1998,16(2):149-157
A clone of NIH3T3 transformant (H3) can yield subcutaneous tumors and experimental pulmonary metastasis in nude mice. Compared
to H3 in culture, the cells after in vivo tumor growth (H3-N) acquired enhanced tumorigenicity and metastatic ability. Also, indirect immunofluorescence revealed that
cellular fibronectin (c-FN) of H3-N was decreased remarkably. We have studied the interactions between H3 and extracellular
matrices to elucidate these phenomena. In the present study, we observed the effect of NIH3T3, H3, and H3-N cultured in type
I collagen gel. Morphologically in the collagen gel, NIH3T3 assumed an extensive elongated fiber-like shape, H3 assumed a
moderately elongated shape, and H3-N assumed a round or spindle shape with short pseudopodia. Compared to conventional cultures
on dishes, cell proliferation of all three types was suppressed in collagen gel, but the degree of the suppression was least
in H3-N. As a result, H3-N grew fastest in collagen gel. The variants which acquired growth advantage in the subcutaneum of
mice also kept it in collagen gel. H3 cells were cultured in type I collagen gel for 4 weeks, a period comparable to that
of tumor formation in nude mice. The cells after this long-term culture (H3-C) acquired enhanced tumorigenicity and metastatic
ability nearly equal to that of H3-N. FACS analysis revealed that the c-FN of H3-C had decreased to a value comparable to
that of H3-N. This means that type I collagen gel as well as subcutaneous tissues could select variants of H3 with less c-FN
through proliferation. Moreover, it is suspected that lattices of type I collagen regulate cell proliferation of fibroblast
via c-FN.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
24.
Shunsuke Imai Susumu Sekigawa Hiroaki Yamamoto Yoshihiko Tsubura Michiyo Miyanaga Nobuhiro Narita Riichiro Mikami 《Pathology international》1982,32(4):677-682
An autopsy case of bronchiolo-alveolar adenocarcinoma in the lung is reported. The patient is a 70-year-old male who complained of severe cough with 500–600 ml watery sputum a day, loss of weight, and general fatigue. Autopsy revealed numerous whitish tumors in various sizes with multiple cysts in both lungs, with no metastasis being found in any other organs. Histological findings identified the tumor as a bronchiolo-alveolar adenocarcinoma originating from the lungs. Electron-microscopic findings showed that the tumor cells were covered by prominent microvilli, and contained abundant irregulary-shaped cytoplasmic vacuoles suggestive of mucin. 相似文献
25.
Purification of fully activated Clostridium botulinum serotype B toxin for treatment of patients with dystonia
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Arimitsu H Inoue K Sakaguchi Y Lee J Fujinaga Y Watanabe T Ohyama T Hirst R Oguma K 《Infection and immunity》2003,71(3):1599-1603
Clostridium botulinum serotype B toxins 12S and 16S were separated by using a beta-lactose gel column at pH 6.0; toxin 12S passed through the column, whereas toxin 16S bound to the column and eluted with lactose. The fully activated neurotoxin was obtained by applying the trypsin-treated 16S toxin on the same column at pH 8.0; the neurotoxin passed through the column, whereas remaining nontoxic components bound to the column. The toxicity of this purified fully activated neurotoxin was retained for a long period by addition of albumin in the preparation. 相似文献
26.
Chiba Y Saitoh N Matsuo K Misawa M 《International archives of allergy and immunology》2002,127(4):285-293
BACKGROUND: Nasal hyperresponsiveness is a common feature of allergic rhinitis, but the underlying mechanisms have yet to be elucidated. The effects of repeated antigen inhalation on the characteristics of histamine H(1) receptors and expression levels of heterotrimeric guanosine 5'-triphosphate-binding proteins in nasal mucosa were investigated to understand the mechanisms of the pathogenesis of nasal hyperresponsiveness in allergic rhinitis. METHODS: Male Hartley guinea pigs were sensitized by the inhalation of dinitrophenylated ovalbumin antigen (10 mg of protein/ml) and repeatedly challenged by inhaling aerosolized dinitrophenylated ovalbumin antigen for 3 weeks. Twenty-four hours after the last antigen inhalation, in vivo nasal responsiveness to histamine was measured. [(3)H]Mepyramine binding assays and immunoblotting for alpha subunits of the G(q) protein were also performed using membrane preparations of isolated nasal mucosae. RESULTS: The histamine-induced increase in intranasal pressure was significantly augmented after repeated antigen challenge, indicating that nasal hyperresponsiveness was achieved. In saturation binding studies, no significant change was observed in the density and antagonist affinity of H(1) receptors in the hyperresponsive animals. On the other hand, the affinity of histamine for high-affinity agonist binding sites in the hyperresponsive group, measured by histamine competition binding studies, was much greater than that in control animals, and these results were affected by guanosine 5'-O-(3-thiotriphosphate) in both groups. Moreover, Galpha(q) levels in nasal mucosal homogenates were significantly increased after repeated antigen challenge. CONCLUSIONS: Elevated G protein levels in nasal mucosa might induce an increased binding affinity of histamine to its receptors, resulting in an augmented nasal response to histamine, that is, nasal hyperresponsiveness, in guinea pigs. 相似文献
27.
Salahuddin Saira; Ookutsu Shoji; Goto Kazufumi; Nakanishi Yoshihiko; Nagata Yukihiro 《Human reproduction (Oxford, England)》1995,10(9):2382-2385
We have evaluated the effects of embryo density and the co-cultureof unfertilized (degenerating) oocytes on the development ofin-vitro fertilized (IVF) mouse embryos. In experiment 1, groupsof one, five, 10 or 20 zygotes were cultured in 20 µldrops of modified human tubal fluid (HTF) medium for 168 h at38.7°C in 5% CO2 and 95% air. As the embryo density increased,significantly (P < 0.05) higher rates of embryos reachedhatched blastocyst stage. In addition, the time required forhatching after IVF was significantly (P < 0.05) shortenedby the increase in embryo density. In experiment 2, 10 IVF zygoteswere cultured with or without 10 unfertilized (degenerating)oocytes in 20 µl drops of HTF medium. The rates of IVFembryos that developed to morula, blastocyst, expanded blastocystand hatched blastocyst stages were decreased significantly (P< 0.01) by culturing embryos with unfertilized oocytes comparedwith culturing embryos alone. In experiment 3, groups of oneor 10 IVF zygotes or 10 IVF zygotes plus 10 unfertilized oocyteswere cultured in 20 µl drops of HTF medium and the numberof cells per blastocyst was examined at 120 h after IVF. Increasingembryo density resulted in a significant (P < 0.05) increasein the number of cells per blastocyst. In contrast, the cellnumber of IVF embryos that developed to blastocyst decreasedsignificantly (P < 0.05) when they were cultured with unfertilizedoocytes. The results suggest that in-vitro development of IVFmouse embryos is enhanced by increasing embryo density and isimpaired by co-culture with unfertilized (degenerating) oocytes. 相似文献
28.
Sasaki J Sugawara K Tanno Y 《Shinrigaku kenkyu : The Japanese journal of psychology》2005,76(5):445-452
The aim of the present study is to explain why there is "the diverse U letter relationship" between embarrassment and psychological distance empirically, in view of Schlenker and Leary (1982)'s self-presentation model of social anxiety. In Study 1, those relationships were observed in three different situations. In Study 2, the main effect of motivation for avoiding rejection and the damage of self-image, and their interaction with embarrassment was examined by hierarchical regression analysis. In the first step, the psychological distance, in the second step, the main effect of both, and in the third step, the interaction was entered. As a result, in the second step, both main effects were significant, but in the third step, only interaction was significant, and both main effects were not significant. This showed that the interaction could predict embarrassment, although the psychological distance was controlled. Finally, this result was discussed in view of social norm. 相似文献
29.
Wang C Horiuchi A Imai T Ohira S Itoh K Nikaido T Katsuyama Y Konishi I 《The Journal of pathology》2004,202(2):215-223
BRCA1 is a putative tumour suppressor gene responsible for a hereditary ovarian cancer syndrome. To clarify the possible involvement of BRCA1 in the development of sporadic ovarian neoplasms, this study analysed the immunohistochemical expression of BRCA1 protein in normal ovarian surface epithelium and 119 epithelial ovarian tumours (19 benign, 24 borderline, and 76 malignant tumours). Loss of heterozygosity (LOH) of BRCA1 was examined using three microsatellite markers to analyse the relationship between BRCA1 expression and alterations of the BRCA1 gene. Methylation of the BRCA1 promoter was also analysed by methylation-specific PCR. In ovarian carcinomas showing heterogeneous expression of BRCA1 protein in the same tumour, LOH and methylation status were analysed using microdissection techniques. Finally, the relationship of BRCA1 expression or its genetic alteration to clinicopathological parameters and patient survival was analysed. Ovarian surface epithelial cells expressed BRCA1 protein. Decreased expression of BRCA1 was found in 16% of benign tumours, 38% of borderline tumours, and 72% of carcinomas. LOH of BRCA1 was demonstrated in no benign tumours, 15% of borderline tumours, and 66% of carcinomas. Methylation of BRCA1 was not detected in benign or borderline tumours, but was present in 31% of carcinomas. Reduced expression of BRCA1 correlated with the presence of gene methylation. The frequency of BRCA1 methylation and LOH was higher in serous carcinomas than in other types. In one of the three serous carcinomas that showed heterogeneous expression of BRCA1, BRCA1-positive borderline-like tumour cells were LOH-positive and methylation-negative, whereas adjacent BRCA1-negative carcinoma cells were LOH-positive and methylation-positive. The prognosis of carcinoma patients did not correlate with BRCA1 expression or genetic status. These findings suggest that reduced expression of BRCA1 protein along with genetic and epigenetic changes of the BRCA1 gene play an important role in the development of sporadic ovarian carcinomas, particularly those of serous histology. 相似文献
30.