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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 molecular cloning and nucleotide sequence of a cDNA clone (pR SOD) for rat CuZn superoxide dismutase (CuZnSOD) is reported. Nucleotide sequence homology with human superoxide dismutase is 86% for the coding region and 71% for the 3' untranslated region. The deduced amino acid sequence is given and the homologies with the sequences reported for other species are presented. Northern blot analysis of total RNA from various rat and mouse tissues and from two mouse cell lines show that pR SOD hybridizes with one mRNA species of about 0.7 kb. The amount of CuZnSOD mRNA in each tissue, measured by densitometry of the Northern blot autoradiograms, correlates with the enzymatic activity based on protein content. These results indicate that the control of CuZnSOD activity in mammalian tissues is largely dependent on the regulation of CuZnSOD mRNA levels. In human liver, fibroblasts and FG2 hepatoma cells, two CuZnSOD mRNAs (0.7 kb and 0.9 kb) are observed. The level of CuZnSOD mRNA in FG2 is 25% that of the liver and four times more abundant than in fibroblasts.  相似文献   
4.
Can ribozymes be used to regulate procaryote gene expression?   总被引:3,自引:0,他引:3  
The in vivo activity of ribozymes designed against mRNA coding for E. coli beta-galactosidase was tested both in intramolecular and in intermolecular conditions. When recombinant M13 phage DNA carrying on the same molecule the information for both the ribozyme and the target was transfected into bacterial cells, ribozyme activity was observed. Conversely, a ribozyme coded by a recombinant M13 vector, but targeted against an mRNA transcribed from the F episome including the remaining part of the beta-galactosidase gene, was inefficient.  相似文献   
5.
We have delineated the molecular lesions causing beta-thalassemia in Spain, a country that has witnessed the passage of different Mediterranean populations over the centuries, in order to evaluate the extent of heterogeneity of these mutations and to make possible simplified prenatal diagnosis of the disorder in that country. The use of the polymerase chain-reaction (PCR) technique to preferentially amplify beta-globin DNA sequences that contain the most frequent beta-thalassemia mutations in Mediterraneans enabled us to rapidly analyze 58 beta-thalassemia alleles in a dot-blot format either by hybridization with allele-specific radiolabeled oligonucleotide probes or by direct sequence analysis of the amplification product. The Spanish population carries seven different beta-thalassemia mutations; the nonsense codon 39 is predominant (64%), whereas the IVS1 position 110 mutation, the most common cause of beta-thalassemia in the eastern part of the Mediterranean basin, is underrepresented (8.5%). The IVS1 mutation at position 6 accounts for 15% of the defects and leads to a more severe form of beta+-thalassemia than originally described in most of the patients we studied. In this study, we demonstrate further the usefulness of the dot-blot hybridization of PCR-amplified genomic DNA in both rapid population surveys and prenatal diagnosis of beta-thalassemia.  相似文献   
6.
Glycophorin A is the major membrane sialoglycoprotein of human erythrocytes and represents a typical example of a transmembrane glycoprotein. The functional role of this cell-surface component is not known but it represents a receptor for viruses, bacteria and parasites like Plasmodium falciparum. 1. Two cDNA clones encoding glycophorin A have been characterized from human fetal cDNA libraries. The longer cDNA extended from the coding region of glycophorin A (residues 4-131) to the 3' untranslated region which included two polyadenylation signals and a poly(A) tail. 2. The structural gene for glycophorin A is located on chromosome 4, q28-q31 as shown by in situ hybridization, thus confirming the previous localization by genetic linkage analysis. 3. Three distinct mRNA species (1.0 kb, 1.7 kb and 2.2 kb) have been identified in erythroid spleen. Northern blot analyses with a probe directed against the 3' untranslated region of the mRNAs indicated that all these species share a homologous 3' non-coding region and that the first polyadenylation signal downstream the stop codon is not used. 4. Preliminary studies by Southern blot analysis of the genomic DNA from normal En(a+) and rare En(a-) donors suggest that the glycophorin A gene has a complex organization and is largely deleted in donors of the En(a-) phenotype (Finnish type) who lack glycophorin A on their red cells.  相似文献   
7.
This is the first report on the isolation ofCryptococcus neoformans from pigeon droppings in China and their serotypes.C. neoformans colonies which produced brown colonies on caffeic acid-cornmeal agar were found in Twenty-five out of thirty-six samples of pigeon droppings. Fifty-one colonies randomly picked from the positive samples were identified asC. neoformans by a commercially available kit for carbon source assimilation test and Christensen's urea agar. Forty (78%) out of the 51 strains were serotyped as A and 11 (22%) as AD. At the same time, seventeen out of nineteen clinical isolates were serotyped as A and 2 as B. There are three findings in our results. One is that onlyC. neoformans var.neoformans strains could be isolated from pigeon droppings, although the varietygattii strains were found in the clinical isolates obtained in the same geographic site in China. The second is that serotype A strains were most frequently seen in natural and clinical materials in the southeast part of China, and serotype AD strains were isolated in pigeon droppings but not in clinical materials. The third is that the coexistence of serotype A and AD cells ofC. neoformans strains in same samples of pigeon droppings were observed.  相似文献   
8.
Larval cuticle ofHelicoverpa (Heliothis)zea and yeast extract added to a minimal medium (MM) induced germination of conidia ofNomuraea rileyi whereas sterile distilled water or MM alone did not. Yeast extract increased mycelial yield, but when cuticle was added, mycelial yield significantly decreased. Proteases and chitinases ofN. rileyi were only expressed when cuticle was added to the MM.This article reports the results of research only. Mention of a proprietary product in this paper does not constitute a recommendation for use by US Department of Agriculture.  相似文献   
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10.
Summary Collagen accumulation is a main pathological feature of diabetic cardiomyopathy. The underlying mechanisms seem to be increased cross linking by reactive carbonyles. The purpose of the study was to decrease the collagen content of total ventricular tissue by the oral administration of thiaproline, which could reduce collagen due to its functions as a proline analogue, blocking collagen production and as a free oxygen radical scavenger, blocking reactive carbonyles and oxygen species and subsequently collagen cross linking.Thiaproline was administered to genetically diabetic db/db mice and compared to untreated animals. Total ventricular collagen as expressed by hydroxyproline was significantly lower in the treated group (means 0.23 micromoles/10 tissue in the treated vs 0.35 micromoles/100 mg tissue in the untreated group, p < 0.001). Significantly more collagen could be eluted in the treated group (p < 0.001) and carboxymethyllysine was significantly reduced in the treated group (p < 0.001). Di-tyrosine and glycemic control did not differ between the groups. Glutathione was significantly increased in the TP treated experimental group (p < 0.001) and lipid peroxidation products were significantly decreased (means 0.221 absorbance in the treated group versus 0.321 absorbance in the untreated diabetic group) correlating with total ventricular collagen content (r = 0.87, p < 0.01).We conclude that thiaproline reduced total ventricular collagen content by inhibiting collagen cross linking as reflected by increased solubility of collagen and expressed by higher elution quantity of collagen. Thiaproline, and/or its metabolites induced increase of heart glutathione which may well have been scavenging reactive carbonyles derived from lipid peroxidation and advanced stage nonenzymatic glycosylation as shown by decreased total ventricular carboxy-methyllysine and lipid peroxidation products paralleling reduced heart collagen content.It remains to be shown that the successful reduction of heart collagen by thiaproline is paralleled by improved functional properties.  相似文献   
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