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排序方式: 共有1165条查询结果,搜索用时 15 毫秒
1.
A case of chromomycosis in which hyperthermia proved effective is reported. The patient was a 56-year-old male bean curd maker who, without any previous history of minor trauma, developed on the extensor side of the left upper arm an eczematous lesion that underwent gradual radial expansion. The lesion showed a well-defined, 7×10 cm infiltrated erythematous plaque with the central area healed and, at the upper and lower borders, adherent scales and crusts on the surface. Histological examination revealed granulomatous changes in the dermis, as well as sclerotic cells within giant cells and microabscesses. On culturing,Fonsecaea pedrosoi was isolated. The patient was treated with disposable chemical pocket warmers, which were secured over the lesion with a rather tight elastic bandage, so that they kept the affected area warm for 24 hours a day. After a month of such hyperthermic treatment, the erythema and infiltration had decreased considerably, and microscopic examination and culture of the crusts both yielded negative results. Examination of biopsy specimens of the lesion after the third month showed that it had cicatrized. The treatment was stopped after 4 months, and no relapse occurred. We also summarize the published results of local hyperthermic treatment of chromomycosis in Japan.  相似文献   
2.
Abstract: The effects of various protein kinase inhibitors on acetylcholine release from the rat hippocampus induced by the local application of NS-3 (montirelin hydrate, CG-3703), a thyrotropin-releasing hormone analogue, into the medial septum-diagonal band were examined using in vivo microdialysis. Perfusion of NS-3 (1 µ M ) into the medial septum-diagonal band for 20 min produced a pronounced and prolonged increase in the hippocampal acetylcholine efflux. Pretreatment of the medial septum-diagonal band with either K-252a, a nonselective protein kinase inhibitor, or selective protein kinase A inhibitor H-89 almost completely blocked the acetylcholine efflux evoked by NS-3, and selective protein kinase C inhibitor calphostin C inhibited the action of NS-3. On the other hand, NS-3 (0.1–10 µ M ) or TRH (1–100 µ M ) increased the cyclic AMP efflux from the medial septum-diagonal band in a concentration-dependent manner, as measured by microdialysis. These findings suggest that protein kinases A and C in the neurons of the medial septum-diagonal band are involved in the mechanism of the prolonged stimulation of acetylcholine release from the hippocampus induced by thyrotropin-releasing hormone and its analogue, NS-3.  相似文献   
3.
A plastein was synthesized with α-chymotrypsin from a dialyzable fraction of a peptic hydrolysate of soybean protein.

The plastein was obtainable also by use of an insoluble preparation of α-chymotrypsin. This may rule out the possibility that the plastein is a product resulting from some chemical peptide-protein (enzyme) aggregation.

No appreciable amount of the plastein was produced when chymotrypsinogen was used instead of α-chymotrypsin.

The plastein synthetic, as well as the protein hydrolytic, activity of α-chymotrypsin was inhibited more or less by a hydrophobic inhibitor (n-hexane), a competitive inhibitor (benzolyl-d,l-phenylalanine), and divalent cations (Zn2+, Hg2+ and Cu2+); the degree of inhibition in each case was approximately similar against both the synthetic and the hydrolytic activities.

Either diisopropylphosphorylation of the β-O of Ser-195 or methylation of the 3-N of His-57 imidazole of α-chymotrypsin repressed the synthetic, as well as the hydrolytic, activity.

Based on these results a possible mechanism was discussed of the plastein synthesis by α-chymotrypsin, especially in relevance to its acylation and deacylation.  相似文献   
4.
From defatted n-paraffin-assimilating yeast cells, a crude protein was obtained by alkaliextraction followed by acid-precipitation. Then the protein was treated with ether until extractable substances were removed exhaustively at this stage. However, at the next stage where the ether-treated protein had been partially hydrolyzed with pepsin, when the hydrolysate was retreated with ether, it was found that ether-extractable substances totalling 270 mg/100 g were obtainable additionally. Chromatographic investigations demonstrated that the substances included significant amounts of aliphatic and aromatic hydrocarbons, some indoles, and a ubiquinone (n = 8).

From the protein hydrolysate (substrate) after the above ether-treatment, a plastein was synthesized with Bioprase under the specific conditions. The plastein was obtained as a precipitate when the whole reaction mixture was treated with aqueous ethanol or acetone. The quantity and quality (nitrogen content) of the plastein depended on the ethanol or acetone concentration. Roughly speaking, the higher the concentration, the more the plastein quantity. The converse relation held for the quality; a plastein precipitated by treatment solely with water showed a higher quality than any other case.  相似文献   
5.
Earlier studies have shown that translation elongation factor 1delta (EF-1delta) is hyperphosphorylated in various mammalian cells infected with representative alpha-, beta-, and gammaherpesviruses and that the modification is mediated by conserved viral protein kinases encoded by herpesviruses, including UL13 of herpes simplex virus type 1 (HSV-1), UL97 of human cytomegalovirus, and BGLF4 of Epstein-Barr virus (EBV). In the present study, we attempted to identify the site in EF-1delta associated with the hyperphosphorylation by the herpesvirus protein kinases. Our results are as follows: (i) not only in infected cells but also in uninfected cells, replacement of the serine residue at position 133 (Ser-133) of EF-1delta by alanine precluded the posttranslational processing of EF-1delta, which corresponds to the hyperphosphorylation. (ii) A purified chimeric protein consisting of maltose binding protein (MBP) fused to a domain of EF-1delta containing Ser-133 (MBP-EFWt) is specifically phosphorylated in in vitro kinase assays by purified recombinant UL13 fused to glutathione S-transferase (GST) expressed in the baculovirus system. In contrast, the level of phosphorylation by the recombinant UL13 of MBP-EFWt carrying an alanine replacement of Ser-133 (MBP-EFS133A) was greatly impaired. (iii) MBP-EFWt is also specifically phosphorylated in vitro by purified recombinant BGLF4 fused to GST expressed in the baculovirus system, and the level of phosphorylation of MBP-EFS133A by the recombinant BGLF4 was greatly reduced. (iv) The sequence flanking Ser-133 of EF-1delta completely matches the consensus phosphorylation site for a cellular protein kinase, cdc2, and in vitro kinase assays revealed that purified cdc2 phosphorylates Ser-133 of EF-1delta. (v) As observed with EF-1delta, the casein kinase II beta subunit (CKIIbeta) was specifically phosphorylated by UL13 in vitro, while the level of phosphorylation of CKIIbeta by UL13 was greatly diminished when a serine residue at position 209, which has been reported to be phosphorylated by cdc2, was replaced with alanine. These results indicate that the conserved protein kinases encoded by herpesviruses and a cellular protein kinase, cdc2, have the ability to target the same amino acid residues for phosphorylation. Our results raise the possibility that the viral protein kinases mimic cdc2 in infected cells.  相似文献   
6.
ERdj5 (also known as JPDI) is a member of PDI family conserved in higher eukaryotes. This protein possesses an N-terminal J domain and C-terminal four thioredoxin domains each having a redox active site motif. Despite the insights obtained at the cellular level on ERdj5, the role of this protein in vivo is still unclear. Here, we present a simple method to purify and identify the disulfide-linked complexes of this protein efficiently from a mouse tissue. By combining acid quenching and thiol-alkylation, we identified a number of potential redox partners of ERdj5 from the mouse epididymis. Further, we show that ERdj5 indeed interacted with two of the identified proteins via formation of intermolecular disulfide bond. Thus, this approach enabled us to detect and identify redox partners of a PDI family member from an animal tissue.  相似文献   
7.

Background

Many studies have focused on the decreasing age of onset of eating disorders (EDs). Because school-age children with EDs are likely to suffer worse physical effects than adults, early detection and appropriate support are important. The cooperation of Yogo teachers is essential in helping these students to find appropriate care. To assist Yogo teachers, it is helpful to clarify the encounter rates (the proportion of Yogo teachers who have encountered ED students) and kinds of requested support (which Yogo teachers felt necessary to support ED students). There are no studies that have surveyed the prevalence rates of ED children by ED type as defined by the Diagnostic and Statistical Manual of Mental Disorders, 5th edition (DSM-5), nor were we able to find any quantitative study surveying the kinds of support Yogo teachers feel helpful to support ED students.

Methods

A questionnaire survey was administered to 655 Yogo teachers working at elementary/junior high/senior high/special needs schools in Chiba Prefecture. The questionnaire asked if the respondents had encountered students with each of the ED types described in DSM-5 (anorexia nervosa (AN), bulimia nervosa (BN), binge eating disorder (BED), avoidant/restrictive food intake disorder (ARFID), and other types of EDs (Others)), and the kinds of support they felt necessary to support these students. The encounter rates and the kinds of requested were obtained and compared, taking their confidence intervals into consideration.

Results

The encounter rates for AN, BN, BED, ARFID, and Others were 48.4, 14.0, 8.4, 10.7, and 4.6 %, respectively. When classified by school type, AN, BN, BED, and ARFID had their highest encounter rates in senior high schools. Special needs schools had the highest rate for Others. The support most required for all ED types was “a list of medical/consultation institutions.”

Conclusions

Our results have clarified how to support Yogo teachers in the early detection and support of ED students. We found that the encounter rate of AN was the highest, and that it is effective to offer “a list of medical/consultation institutions” to junior and senior high schools where the encounter rates for AN are high.
  相似文献   
8.
Lysine (K) type cationic lipid with a propyl spacer and ditetradecyl hydrophobic moieties composing liposomes, K3C14, previously studied for gene delivery, were reported to activate the NLRP3 inflammasomes in human macrophages via the conventional phagolysosomal pathway. In this study, K3C16, a propyl spacer bearing lysine type lipids with dihexadecyl moieties (an extension of two hydrocarbon tail length) were compared with K3C14 as liposomes. Such a small change in tail length did not alter the physical properties such as size distribution, zeta potential and polydispersity index (PDI). The NLRP3 activation potency of K3C16 was shown to be 1.5-fold higher. Yet, the toxicity was minimal, whereas K3C14 has shown to cause significant cell death after 24 h incubation. Even in the presence of endocytosis inhibitors, cytochalasin D or dynasore, K3C16 continued to activate the NLRP3 inflammasomes and to induce IL-1β release. To our surprise, K3C16 liposomes were confirmed to fuse with the plasma membrane of human macrophages and CHO-K1 cells. It is demonstrated that the change in hydrophobic tail length by two hydrocarbons drastically changed a cellular entry route and potency in activating the NLRP3 inflammasomes.  相似文献   
9.
We previously reported that immature starfish oocytes contain a novel 530-kDa proteasome-associating complex PC500 [previously named PC530; E. Tanaka, M. Takagi Sawada, C. Morinaga, H. Yokosawa, H. Sawada, Isolation and characterization of a novel 530-kDa protein complex (PC 530) capable of associating with the 20S proteasome from star fish oocytes, Arch. Biochem. Biophys. 374 (2000) 181-188]. In the present study, in order to obtain an insight into the biological function of this complex, we investigated the effects of anti-PC500 monoclonal antibodies on oocyte maturation of the starfish Asterina pectinifera. A monoclonal antibody 7C5 strongly inhibited germinal vesicle breakdown (GVBD) in a concentration-dependent manner. In contrast to the inhibitory effect of the 7C5 antibody on GVBD, no inhibition of egg cleavage was observed in a 7C5-antibody-microinjected single blastomere in a 2-cell stage embryo. These results indicate that PC500 plays a key role in starfish oocyte maturation in a meiosis-specific manner.  相似文献   
10.
A new cell line of human ovarian clear cell carcinoma (CCC), TU-OC-2, was established and characterized. The cells were polygonal in shape, grew in monolayers without contact inhibition and were arranged in islands like pieces of a jigsaw puzzle. The chromosome numbers ranged from 41 to 96. A low rate of proliferation was observed and the doubling time was 37.5 h. The IC50 values of cisplatin, 7-ethyl-10-hydroxycamptothecin (SN38), which is an active metabolite of camptothecin, and paclitaxel were 7.7 μM, 17.7 nM and 301 nM, respectively. The drug sensitivity assay indicated that TU-OC-2 was sensitive to SN38, but resistant to cisplatin and paclitaxel. Mutational analysis revealed that TU-OC-2 cells have no mutations of PIK3CA in exons 9 and 20 and of TP53 in exons 4–9. We observed the loss of ARID1A protein expression in TU-OC-2 cells by western blot analysis and in the original tumor tissue by immunohistochemistry. This cell line may be useful for studying the chemoresistant mechanisms of CCC and exploring novel therapeutic targets such as the ARID1A-related signaling pathway.  相似文献   
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