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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.
Margot S. Kruskall MD Elizabeth E. Eynon Zuheir Awdeh Chester A. Alper Edmond J. Yunis 《Immunogenetics》1987,26(4-5):216-219
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.
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
5.
Yoshinori Nio MD Takahiro Shiraishi Michihiko Tsubono Hideki Morimoto Chen-Chiu Tseng Kazuya Kawabata Yoshikazu Masai Manabu Fukumoto Takayoshi Tobe 《Biotherapy》1992,4(2):81-86
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
6.
Giuseppe Familiari MD Vincenzo Toscano Pietro M. Motta 《Cell and tissue research》1985,240(3):519-528
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
7.
Gabriella Fóris MD PhD George A. Medgyesi Mátyás Hauck 《Molecular and cellular biochemistry》1986,69(2):127-137
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
8.
Effect of human T-cell leukemia virus type I tax protein on activation of the human vimentin gene. 总被引:28,自引:9,他引:19 下载免费PDF全文
We report that the expression of the vimentin gene, a cytoskeletal growth-regulated gene, is activated in trans by the Tax (p40x) transactivator protein encoded by the human T-cell leukemia virus type I. Expression of the Tax protein activates a number of cellular genes, such as those coding for the alpha chain of the high-affinity interleukin-2 receptor and interleukin-2. These findings indicate that the Tax protein is involved in the unregulated T-cell growth associated with human T-cell leukemia virus type I infection. Higher levels of vimentin mRNA were expressed in two human T-cell leukemia virus type I-transformed T cell lines, C91/PL and C81-66/45, when compared with that in Jurkat T cells. We demonstrate that this activation is conferred by the vimentin upstream flanking sequences. Indeed, enhanced activity was detected when constructs with the vimentin promoter linked to the chloramphenicol acetyltransferase gene were transfected in HeLa cells and in two cell lines of hematopoietic origin (Jurkat T lymphoblastoid cells and U937 promonocytic cells) together with a Tax expression plasmid. By introducing a series of deletions in the vimentin promoter, we further restrict these sequences to 30 base pairs, located between 241 and 210 base pairs upstream of the mRNA cap site. A 40-base-pair oligonucleotide containing this regulatory region proved sufficient to confer Tax inducibility upon a heterologous promoter linked to chloramphenicol acetyltransferase. Importantly, this segment includes an 11-base-pair promoter segment that has homology with the binding site for the NF-kappa B transactivating factor. Our findings indicate that constitutive expression of the vimentin gene under the control of the Tax protein may be relevant in understanding the progression of the lymphoproliferative process associated with human T-cell leukemia virus type I infection. 相似文献
9.
Peripheral T-lymphocyte activation by human T-cell leukemia virus type I interferes with the CD2 but not with the CD3/TCR pathway 总被引:5,自引:4,他引:1
Human T-cell leukemia virus type I (HTLV-I) is etiologically associated with adult T-cell leukemia, an aggressive lymphoproliferative disorder, and with chronic neurological diseases. In vitro it can infect several types of cells but transforms only human T lymphocytes. We have previously shown that HTLV-I viral particles, even when noninfectious, were able to activate human resting T lymphocytes, suggesting that this activation step may be important in the initiation of the lymphoproliferative process. In the present study, we first demonstrate that in contrast to other mitogenic stimuli, HTLV-I has the unique property to activate human resting T cells in the absence of accessory cells. We then investigate the relationship between HTLV-I-induced T-cell activation and the classical well-known pathways of activation, namely, the CD3/TCR and CD2 pathways. Competitive blocking experiments were performed in which the effects of monoclonal antibodies (MAb) to the CD3/TCR complex or to the CD2 molecule were evaluated on the HTLV-I activation of T cells and compared with that obtained on phytohemagglutinin (PHA)-stimulated cells. It was found that anti-CD3 or -TCR MAb strongly suppress the proliferative response of T cells to PHA, but are significantly less efficient in inhibiting the activation initiated by HTLV-I. By contrast, MAb recognizing specific epitopes of the CD2 molecule inhibit the proliferative response of T cells to PHA or to HTLV-I to the same extent. The results provide evidence that HTLV-I virions interfere mainly with activation via CD2 but not via the CD3/TCR complex. Considering the earlier expression of the CD2 molecule on human T-cell precursors, these observations might be relevant to the characterization of the differentiation stage at which viral infection could interfere with the development and the maturation of T lymphocytes. 相似文献
10.
Lei Peng-Cheng Takashi Yoshiike Hitoshi Yaguchi Hideoki Ogawa MD PhD 《Mycopathologia》1993,122(2):89-93
Defense mechanisms againstSporothrix schenckii were studied using mouse models. After an intracutaneous injection of the yeast form ofS. schenckii to the dorsal skin of the congenitally athymic nude and normal heterozygote littermate mice, nodules were formed. They regressed and disappeared in 10 weeks in the case of normal mice. On the other hand, nodules and then ulceration developed progressively in nude mice until all animals expired by dissemination of microorganisms at the 11th week of inoculation. Histopathologically the migrated cells were similar in both the normal and the nude mice, particularly during the early phase (within 24 h), with infiltration by PMNs being predominant. Fragmentation ofS. schenckii commenced early during the 12–24 h stage of inoculation in the normal mice, while such fragmentation was scarce in nude mice even though numerous PMNs accumulated. Microscopic observations in the early stages (within 24 h of inoculation) suggested that the lack of killing activity by PMNs in nude mice contributes more to the impaired defense than the lack of macrophage activation by T-cells. 相似文献