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2.
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   
3.
The HLA class I antigen B44 is found in each of two different extended major histocompatibility haplotypes (allele combinations of HLA-B, HLA-DR, and complement genes BF, C2, C4A, and C4B in linkage disequilibrium). Using isoelectric focusing, two variants of HLA-B44 were identified. The basic variant was found in all cell lines with the extended haplotype HLA-B44, DR7, FC31, and the acidic variant in all cell lines with the extended haplotype HLA-B44, DR4, SC30. The occurrence of each antigen variant with a unique extended haplotype explains previous observations concerning the nonrandom association of B44 variants with DR antigens.  相似文献   
4.
A transport system for coenzyme A in isolated rat heart mitochondria   总被引:2,自引:0,他引:2  
The ability of isolated rat heart mitochondria to take up coenzyme A (CoA) from the incubation medium was studied. Mitochondria accumulated CoA in a time- and concentration-dependent manner. The accumulation process occurred in two phases. Within the first 30 s of incubation, mitochondrial content of CoA increased, and this phase did not plateau in the concentration range studied. Following this initial increase, a second slower phase of CoA accumulation occurred which plateaued around 50 microM CoA. The initial phase was decreased significantly by ATP or by carboxyatractyloside. In contrast, the presence of ATP or carboxyatractyloside did not affect the second phase. Decreasing the temperature from 30 to 0 degrees C did not affect the initial phase, but the second phase was almost abolished. In the presence of metabolic inhibitors (either 2,4-dinitrophenol or a combination of rotenone and antimycin), the initial "binding" phase was not affected; but the second "uptake" phase was abolished. These results suggest that the first phase of mitochondrial CoA accumulation is probably CoA binding to adenine recognizing sites on the mitochondria while the second phase may represent a specific uptake process for CoA which, although not directly ATP-dependent, is energy-dependent.  相似文献   
5.
Paracoccidioidomycosis was induced in immunized (IM) and non-immunized (NI) mice. The histopathology, the number of fungi in the lungs, the cellular (footpad test — FPT and macrophage inhibition factor assay — MIF) and humoral (immunodiffusion test) immune response were investigated serially postinfection. In the IM mice, at days 1 and 3, there was intense and predominant macrophagic-lymphocytic alveolitis with loose granulomatous reaction; at day 30, inflammation was mild. In the NI group, up to day 3, the lesions were focal; later there was formation of extensive epithelioid granuloma. The number of fungi in IM mice were always smaller than those of NI group. Immunization alone induced positive FPT and MIF indices with low titer of antibody. After infection, there was a significant decrease of the FPT indices in the IM group, which we interpreted as desensitization due to trapping of sensitized lymphocytes in the lungs. In conclusion, (1) The lesional pattern of pulmonary paracoccidioidomycosis in IM mice was similar to that of a hypersensitivity pneumonitis. This reaction was probably effective in reducing the extension of the infection and decrease the number of fungi. (2) In this model, pulmonary resistance against P. brasiliensis seems to be related to local and systemic delayed-type hypersensitivity reaction.  相似文献   
6.
The present study was designed to evaluate the effects of a recombinant human G-CSF (rhG-CSF) and a mutein G-CSF(KW-2228) on leucopenia and tumor growth in mice treated with 5-fluorouracil (5-FU). In normal mice, the number of leucocytes (white blood cell, WBC) reached the peak 12 hours after a single injection of either type of G-CSF and decreased to the normal level after 24 hours. Daily administration induced a continuous increase in the WBC count, however, administrations at intervals did not. Meth-A fibrosarcoma was subcutaneously inoculated into the backs of syngeneic BALB/c mice. The mice were treated with 5-FU alone or with G-CSFs. Chemotherapy with 5-FU alone resulted in leucopenia and an insignificant inhibition of tumor growth. The conjunctive administration of G-CSFs with 5-FU resulted in a significantly augmented inhibition of tumor growth, and leukopenia was not seen. This augmenting effect was more prominent with KW-2228.These results suggest that in 5-FU chemotherapy G-CSFs may be beneficial in restoring the number of leucocytes from leucopenic state and in augmenting the tumor inhibitory effect. Furthermore, KW-2228 may be more beneficial than the natural type rhG-CSF.  相似文献   
7.
The properties and regulation of pantothenate kinase from rat heart   总被引:2,自引:0,他引:2  
Pantothenate kinase (ATP:D-pantothenate 4'-phosphotransferase, EC 2.7.1.33), the first enzyme in the pathway of CoA synthesis, was partially purified from rat heart. A study of the properties of the kinase showed that it possesses a broad pH optimum between 6 and 9, is activated or inhibited nonspecifically by various anions, and has MgATP as the nucleotide substrate. The Km for MgATP is 0.6 mM and that for pantothenate is 18 microM. CoA and acyl esters of CoA are inhibitors of the kinase with the inhibition by acetyl-CoA being only slightly greater than that by free CoA. The inhibition by free CoA is uncompetitive with respect to pantothenate concentration, with a Ki for inhibition of 0.2 microM. L-Carnitine was found to be a nonessential activator of the kinase. This compound had no effect by itself but specifically reversed the inhibition of the kinase by CoA. The Ka for deinhibition by L-carnitine is 0.27 mM. Free carnitine content was measured in perfused hearts and is found to vary in correlation with perfusion conditions that are known to alter rates of intracellular phosphorylation of pantothenate. These properties of pantothenate kinase provide a potential mechanism for the control of CoA synthesis. The enzyme is regulated by feedback inhibition by CoA and its acyl esters and this inhibition is modified by changes in the concentration of free carnitine.  相似文献   
8.
Summary Morphological alterations induced by dehydroepiandrosterone (DHA) were studied in polycystic mouse ovaries (PCO). Treated mice showed ovulatory failure and cystic changes; cysts and follicles in various stages of growth and atresia were present although corpora lutea were absent. The levels of testosterone, dihydrotestosterone, 3- and 3-androstanediol, estrone and androstenedione increased, whereas estradiol was not detectable.The ultrastructure of granulosa cells in healthy and atretic follicles was similar to that of control animals, although the membrana granulosa in cysts was reduced to a monolayer of flattened cells. The theca interna of healthy and atretic follicles and ovarian cysts showed ultrastructural signs of abnormal steroidogenic stimulation.No significant differences (0.7<P<0.8) were found between the extensive surface area of gap junctions of healthy follicles of control and DHA-treated animals. On the P-face of granulosa cells of large healthy follicles, meandering strands of tight junctional particles were observed; their average length was significantly longer than those in healthy follicles of control animals (P<0.001). This increase was probably related to the large amounts of androgens present in the treated animals.Theca interna cells possessed small gap junctions; no significant differences (P>0.9) in gap-junction surface area were observed between DHA-treated and control animals. These results suggest that the size of gap junctions is probably unrelated to the steroidogenic activities of theca cells.The following trivial names have been used: Dihydrotestosterone: 5-androstan 17 ol-13 one; 3-androstanediol: 5-androstan 3,17 diol; 3-androstanediol: 5-androstan 3,17 diol  相似文献   
9.
Summary Met-enkephalin (ME) exerts a bimodal effect on functional activities of rat peritoneal macrophages (PM); in a range of low concentration (10-9-10-7 M) antibody dependent cellular cytotoxicity (ADCC)was markedly stimulated with a simultaneous decrease of Fc receptor (FcR) mediated phagocytosis while the opposite was observed at 10-6-10-5 M concentrations.Studying the possible underlying mechanism(s) the followings were recorded: (1) ME in all applied concentrations induced an early Na+ influx which was followed by a Ca2+ efflux in the range of low concentrations. In the range of high concentrations Na+ influx was accompanied by a Ca2+ influx. (2) ME at 10-8 M concentration induced a rise in cGMP level with a plateau in the 60–120th min of incubation. This effect was prevented by 10-5 M of naloxone. At 10-6 M concentration a transient rise of cAMP level was recorded which was not affected by naloxone. (3) Verapamil in 10-6 M abolished both the Ca2+ influx and the rise in cAMP level induced by 10-6-10-5 M ME but not the rise in cGMP level induced by lower ME concentrations. (4) cAMP elevation by high ME concentrations was abolished by enkephalinase inhibitory puromycin. (5) PM-enkephalinase as assessed by the cleavage of fluorogenic substrate L-alanine beta naphthylamide (ABNA), was inhibited by 10-6-10-5 M of ME. This inhibition was abolished by verapamil, but not affected by naloxone. In the range of low concentrations ME appears to act on specific delta opioid receptors and its action is positively coupled to guanylate cyclase. In relatively higher concentrations ME-action is not mediated by specific delta opioid receptors and it appears to involve Ca2+ influx, adenylate cyclase activation as well as the processing of hormone by PM-enkephalinase.  相似文献   
10.
Livers from nonfasted rats were perfused in situ under conditions known from previous studies in this laboratory to increase or decrease overall endogenous proteolysis. At the termination of the experiments, lysosomal alterations were evaluated by the increase in free acid phosphatase or N-acetyl-β-D-glucosaminidase that occurred when tissue homogenates were subjected to osmotic shock in hypotonic sucrose. In control perfusions, osmotic sensitivity increased spontaneously over unperfused values, reaching maximum by 60 min or earlier. Additions of insulin, amino acid mixtures, or cycloheximide in amounts known to suppress proteolysis prevented this spontaneous perfusion effect or, when added at 60 min, rapidly reversed it. Glucagon alone during perfusion did not increase osmotic sensitivity further; however, stimulation with glucagon was observed when the perfusion effect was suppressed by insulin or cycloheximide. Anoxia, induced by gassing with nitrogen instead of oxygen, markedly reduced the perfusion effect and also doubled the amount of free acid phosphatase in the initial isotonic homogenates. Total acid phosphatase activities in the perfusion experiments were not significantly different from unperfused values and, with the exception of the anoxia perfusions, the amounts of free enzyme present in the initial isotonic sucrose homogenates did not change.  相似文献   
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