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71.
72.
Pulmonary metastasis from low-grade endometrial stromal sarcomas (ESSs) occasionally are found after long, disease-free periods, mostly as incidental histological or radiological discoveries. We describe a case of low-grade ESS presenting as nodular pulmonary metastases finally diagnosed by estrogen-receptor staining, cytogenetic and fluorescence in situ hybridization (FISH) analyses, and perusal of the histology of hysterectomy material. An abnormal nodule in the lung field was discovered by means of chest X-ray of a 47-year-old woman. She had been disease free for 13 years after hysterectomy for an alleged leiomyoma. A computed tomographic scan revealed nodules, with fluctuation in size over the 2-year period, in both lungs. Finally the lesion in the left lung was resected, and pulmonary endometriosis was suspected because of the lack of stromal cell nuclear atypia and positive immunohistochemical reactions for estrogen and progesterone receptors. However, a characteristic karyotype was identified cytogenetically: 46, XX, t(7;17)(p15;q11), the translocation of which, specific to ESS, was confirmed by FISH analysis. A final diagnosis of pulmonary metastases from an ESS could be made by reviewing the histology of the previous uterine tumor. In this case, metastatic lesions from an ESS showed a decrease as well as an increase in size, despite the malignant potential. Immunostaining for estrogen and progesterone receptors and cytogenetic and FISH analyses, together with clinical information on the past gynecological history, are valuable diagnostic keys.  相似文献   
73.
The effect of the thromboxane (TX) A2 synthetase inhibitor, OKY-046, on human leukocyte histamine release and bronchial hypersensitivity in asthmatic subjects was evaluated. It was found that OKY-046 inhibited IgE- and Ca2+ ionophore A23187-mediated leukocyte histamine release in a dose-dependent fashion (IC50: 1.0 and 3.0 X 10(-3) M, respectively) and that OKY-046 could diminish bronchial hypersensitivity, determined by leukotriene D4 inhalation, following a 2-week oral medication. These data suggest that the TXA2 synthetase inhibitor can produce favorable effects upon the course of immediate-type hypersensitivity reactions.  相似文献   
74.
Multiple protein kinase C (PKC) isozymes are present in neurons, where they regulate a variety of cellular functions. Due to the lack of specific PKC isozyme inhibitors, it remains unknown how PKC acts on its selective target(s) and achieves its specific actions. Here we show that a PKC binding protein, enigma homolog (ENH), interacts specifically with both PKCepsilon and N-type Ca2+ channels, forming a PKCepsilon-ENH-Ca2+ channel macromolecular complex. Coexpression of ENH facilitated modulation of N-type Ca2+ channel activity by PKC. Disruption of the complex reduced the potentiation of the channel activity by PKC in neurons. Thus, ENH, by interacting specifically with both PKCepsilon and the N-type Ca2+ channel, targets a specific PKC to its substrate to form a functional signaling complex, which is the molecular mechanism for the specificity and efficiency of PKC signaling.  相似文献   
75.
A toxic substance (P-II fraction), fractionated from the pedicellariae of the sea urchinToxopneustes pileulus, dose-dependently caused the histamine release from rat peritoneal mast cells. The histamine release induced by P-II fraction increased with time, while compound 48/80 caused a more rapid histamine release. The dose-response curve for P-II fraction was studied with concentration 0.03–2.0 mg/ml. This reaction was dependent on Ca2+ and temperature. When glucose (5.5. mM) was omitted during the incubation step, the histamine release induced by P-II fraction was significantly reduced as compared to that of compound 48/80. Pyruvate reversed this reduction. On the other hand, the histamine release induced by P-II fraction was effectively potentiated by the addition of glucose (11.0 mM), but not that by compound 48/80. These results suggest that P-II fraction-induced histamine release differs from that of compound 48/80 disregards to the effects of glucose, because this histamine release appears to be more sensitive to the glycolytic pathway than compound 48/80-induced histamine release.  相似文献   
76.
For almost 20 years, the neutralizing-epitope site specific for influenza B virus Victoria group isolates was conserved at the "tip" of the hemagglutinin molecule; however, it was not detected in half of the isolates from the 2002-2003 epidemic in Japan. Amino acid substitutions (D164E or N165K) were observed at the "tip", and the epitope was altered. The viral antigenicities were affected, and human antibodies did not substantially inhibit the hemagglutination in the hemagglutination inhibition tests. It is suspected that such variants will be important in future epidemics.  相似文献   
77.
In a previous study, we isolated and characterized a new serotype k of Streptococcus mutans from human blood and oral cavities. Analysis of the genes involved in biosynthesis of the serotype-specific polysaccharide of serotype k strains revealed that the serotype k-specific nucleotide alignment was commonly present in the 5' region of the rgpF gene (350 bp from the initial sequence) compared to the reference strains, and then a method for rapid identification of serotype k strains was developed by use of PCR with primers designed on the basis of the sequence of the variable region. PCR assays with primers specific for amplification of serotype k strains showed a negative reaction with serotype c, e, and f strains and a positive reaction with serotype k strains, with the sensitivity for identification of the serotype k strains shown to range from 5 to 50 cells. Next, the frequency of positive reactions for serotype k-specific primers was surveyed with DNA taken from saliva samples from 200 subjects (2 to 18 years of age), and 10 of those showed a positive reaction, which was higher than the frequency in our previous survey with a serological method. In addition, all saliva samples from subjects with serotype k strains in our previous study were shown to be positive with the serotype k-specific primers. These results indicate that this new PCR method is effective for identification of subjects with S. mutans serotype k.  相似文献   
78.
Superantigens stimulate T-cell-receptor Vbeta-selective T-cell proliferation accompanying the release of cytokines, which may eventually protect the host from microbial infections. We investigated here whether superantigens can rescue the host from lethal bacterial infection. Mice were pretreated with Staphylococcus aureus enterotoxin B (SEB) 1 and 2 days before bacterial infection, and the mortality of infected mice was assessed. SEB pretreatment protected mice from lethal infection with Listeria monocytogenes but not from lethal infection with Streptococcus pyogenes. This enhanced protection was also observed upon pretreatment with recombinant streptococcal pyrogenic exotoxin A. Furthermore, L. monocytogenes-specific delayed-type hypersensitivity (DTH) due to type 1 helper T (Th1) cells and the cytotoxicity of CD8(+) T cells were significantly enhanced after SEB administration and bacterial infection. Depletion of either CD4(+) T cells or CD8(+) T cells in SEB-pretreated mice completely abolished this protection. This phenomenon was ascribed to the elimination of L. monocytogenes-specific CD8(+) cytotoxic T lymphocytes (CTL). It was found that CD4(+) T cells contributed to the induction of the CTL populations. Furthermore, SEB pretreatment of heat-killed L. monocytogenes-immunized mice enhanced the protection from challenge of L. monocytogenes. Taken together, these results indicated that administrations of superantigens protected mice from infection with L. monocytogenes, which was dependent on the enhanced L. monocytogenes-specific CTL activity in the presence of CD4(+) T cells, and superantigens exhibited adjuvant activity in the immunization against intracellular pathogens.  相似文献   
79.
In order to study the relationship between personality and the development of diabetic retinopathy in patients with diabetes mellitus, diabetics with retinopathy (severe group) and sex-, age-, and duration-matched diabetics without complications were tested by psychological tests, and interviewed. The result of the Yatabe-Guilford personality test (Y-G) and Spielberger's State and Trait Anxiety Inventory revealed that subjects were emotionally and socially stable and well-adjusted types and less anxious in the severe group than in the mild group. The interview findings reveal that the severe group had neglected the medical treatment and the diet therapy for significantly longer periods of time and the incidence of a childhood parental separation was significantly higher in the severe group than in the mild group. Discussion focuses on the severe diabetics' coping behavior which is characterized by the neglect of medical treatment and diet therapy for extended periods of time, which in turn resulted in diabetic retinopathy and other complications. Such coping behavior is shown to be equivalent to that found in the alexithymic behavioral syndrome.  相似文献   
80.
The distribution of DNP groups in various tissues of guinea-pigs following intravenous injection of DNBSO3Na was investigated by an immunofluorescent method using FITC-labelled anti-DNP antibody. DNP groups were detected either in the cytoplasms of epidermal cells or on/in lymphoid tissue cells. The epidermal distribution of DNP groups was shown in the skin obtained from 5 min to 3 days after injection. There was no fundamental difference in the epidermal localization of DNP groups between at the previously tested site and at virgin site in DNCB sensitized animals. Unreacted DNBSO3Na was demonstrated in the blood plasma of DNBSO3Na injected animals. The injection of either DNP-lysine or 2,4-dinitrophenol was found incapable of inducing flare up reaction and no epidermal localization of DNP groups in the sensitized animals was observed. A possibility that intravenously injected DNBSO3Na forms a complete antigen by conjugation with epidermal proteins and sensitized cells, which have been indicated by Polak, Turk & Frey (1973) to remain at the site of old contact reaction, react with the antigen resulting in flare up reaction, is suggested.  相似文献   
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