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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.
Ultrastructural data are presented on time-course changes in isolated rat hepatocyte suspensions exposed either to 1.2 or 1.8 mM CCl4 for up to 1 h. The subcellular changes at the lower concentration, but not the higher, are shown to closely parallel those reported to occur in rat hepatocytes following ingestion of CCl4.  相似文献   
4.
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   
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.
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   
8.
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   
9.
While the majority of sympathetic neurons are noradrenergic, a minority population are cholinergic. At least one population of cholinergic sympathetic neurons arises during development by a target-dependent conversion from an initial noradrenergic phenotype. Evidence for retrograde specification has been obtained from transplantation studies in which sympathetic neurons that normally express a noradrenergic phenotype throughout life were induced to innervate sweat glands, a target normally innervated by cholinergic sympathetic neurons. This was accomplished by transplanting footpad skin containing sweat gland primordia from early postnatal donor rats to the hairy skin region of host rats. The sympathetic neurons innervating the novel target decreased their expression of noradrenergif traints and developed choline acetyltransferase (ChAT) activity. In addition, many sweat gland-associated fibers acquired acetylcholinesterase (AChE) staining and VIP immunoreactivity. These studies indicated that sympathetic neurons in vivo alter their neurotransmitter phenotype in response to novel envronmental signals and that sweat glands play a critical role in the cholinergic and peptidergic differentiation of the sympathetic neurons that innervate them. The sweat gland-derived cholinergic differentiation factor is distinct from leukemia inhibitory factor and ciliary neurotrophic factor, two well-characterized cytokines that alter the neurotransmitter properties of cultured sympathetic neurons in a similar fashion. Recent studies indicate that anterograde signalling is also important for the establishment of functional synapses in this system. We have found that the production of cholinergic differentiation activity by sweat glands required sympathetic innervation, and the acquisition and maintenance of secretory competence by sweat glands depends upon functional cholinergic innervation. 1994 John Wiley & Sons, Inc.  相似文献   
10.
Vasoactive intestinal peptide (VIP) expression increases in sympathetic neurons when they are grown in dissociated cell or explant cultures and when they are axotomized in vivo. In dissociated cell culture, the magnitude of the VIP increase was reduced when nonneuronal cells were removed and medium conditioned by ganglionic nonneuronal cells increased VIP in neuron-enriched cultures. Antiserum Against cholinergic differentiation factor (also leukemia inhibitory factor; CDF/LIF), but not against ciliary neurotrophic factor, immunoprecipitated this activity. Medium conditioned by sympathetic ganglion explants also contained a VIP-stimulatory molecule that was immunoprecipitated by CDF/LIF antiserum, and CDF/LIF antiserum partially blocked VIP induction in explants. CDF/LIF mRNA was increased in dissociated cell cultures, in ganglion explants and in vivo after axotomy. Our results suggest that CDF/LIF released from ganglionic nonneuronal cells plays an important role in regulating VIP after axotomy. 1994 John Wiley & Sons, Inc.  相似文献   
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