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1.
Retention of habitat fragments within the urban matrix can provide critical resources for the maintenance of regional biodiversity while still providing socio-economic value. Euglossini bees are important components in a community as they are important pollinators for economically valuable plants as well as hundreds of orchid species. However, some species are very sensitive to environmental impacts like urbanization. This study presents the role of antique urban fragments in a historical city in Brazil and compares it with a conservation area on the aspects of orchid bee assemblage, such as richness, composition, and abundance. Four fragments inside the city of Ouro Preto and three inside Parque Estadual do Itacolomi (PEIT) were sampled for Euglossini bees. Sorensen similarity index was used to compare community composition. The Mantel test was applied to verify the hypothesis that an urban center is a barrier for the mobility of the individuals. Fourteen Euglossini species from the region were registered. Close to 75% of the sampled bees were collected from the PEIT sampling areas. The fragments presented differences in Euglossini richness and abundance. A majority of the sampled fragments were dominated by the Eulaema cingulata Fabricius, Eulaema nigrita Lepeletier, and Euglossa securigera Dressler species. We found differences on community composition between the fragments localized in PEIT and those located in the urban center. The data suggest that there is a possible flux of individuals between the sampled fragments. The various small forest fragments in Ouro Preto, primarily in backyards, may also serve as stepping stones between sampled fragments. 相似文献
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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
4.
Lipid emulsions were prepared with a similar size and lipid composition to natural lymph chylomicrons, but in which the surface phospholipid was either egg phosphatidylcholine, dioleoyl-, dimyristoyl-, dipalmitoyl- or 1-palmitoyl-2-oleoylphosphatidylcholine (EYPC, DOPC, DMPC, DPPC or POPC). When injected into the bloodstream of conscious rats, the emulsions containing EYPC or POPC were metabolized similarly to natural chylomicrons, consistent with rapid lipoprotein lipase-mediated hydrolysis of triacylglycerols, followed by hepatic uptake of the remnants derived from the emulsions. Phospholipids from the injected emulsions were removed more slowly and became associated with the high-density lipoprotein fractions of the plasma. Emulsions containing DPPC were metabolized differently. Triacylglycerols disappeared very slowly from plasma, indicating lack of hydrolysis by lipoprotein lipase, and phospholipid radioactivity did not transfer to high-density lipoprotein. With emulsions containing DMPC, the plasma removal rates for emulsion triacylglycerols and cholesteryl esters were fast, but phospholipid radioactivity failed to transfer to the high-density lipoprotein fractions of plasma. With DOPC emulsions, clearances were slower than EYPC or POPC emulsions, but transfer to high-density lipoproteins was efficient. Therefore, an unsaturated chain at the glycerol 2-position was necessary for rapid hydrolysis by lipoprotein lipase and for efficient transfer of phospholipids to high-density lipoproteins. With an unsaturated chain at the glycerol 2-position, a saturated chain at the glycerol 1-position optimized the rate of remnant removal from the plasma. 相似文献
5.
G-11 staining in Turner's syndrome with mos 45,X/46,X,r(?) 总被引:2,自引:0,他引:2
J C de Almeida J C Llerena D Molina Gomes R Rita Martins M Jung D F Reis A G Cunha 《Annales de génétique》1985,28(1):37-41
Mos 45,X/46,X,r(?) in 4 patients with Turner's syndrome and no signs of virilization, and in one pair of monozygotic twins, one of them with clitoral hypertrophy, was studied using combined cytogenetic techniques and specially G-11 staining for the characterization of the X or Y origin of the rings. In all 6 patients the ring was G-11 positive, attesting its Y origin. Both twins were operated and bilateral streak gonads with a bilateral nodule of testicular tissue were found. Similar small rings were also studied in one patient with mos 46,XX/46,X,r(X) and in one nonvirilized Turner's syndrome patient with a larger ring; in these two cases the ring was G-11 negative. It seems that the small rings occasionally found in Turner's syndrome are more frequently from Y origin and therefore prophylactic gonadectomy should be considered. 相似文献
6.
Detection of virulence factors in culturable Escherichia coli isolates from water samples by DNA probes and recovery of toxin-bearing strains in minimal o-nitrophenol-beta-D-galactopyranoside-4-methylumbelliferyl-beta-D-g luc uronide media. 总被引:1,自引:1,他引:0 下载免费PDF全文
A total of 449 Escherichia coli isolates in treated and raw water sources were submitted to DNA-DNA hybridization using seven different DNA probes to detect homology to sequences that code for Shiga-like toxins I and II; heat-stabile and heat-labile toxins, adherence factors EAF and eae, and the fimbrial antigen of entero-hemorrhagic E. coli. Fifty-nine (13%) of the isolates demonstrated homology with one or more specific DNA probes. More than 50% of the isolates in treated water were not recovered in MMO-4-methylumbelliferyl-beta-D-glucuronide media designed for detection of this indicator. 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
9.
Coelho-Rocha Nina Dias de Jesus Luís Cláudio Lima Barroso Fernanda Alvarenga Lima da Silva Tales Fernando Ferreira Enio Gonçalves José Eduardo dos Santos Martins Flaviano de Oliveira Carvalho Rodrigo Dias Barh Debmalya Azevedo Vasco Ariston de Carvalho 《Probiotics and antimicrobial proteins》2023,15(1):160-174
Probiotics and Antimicrobial Proteins - Beneficial effects of Lactiplantibacillus plantarum strains have been widely reported. Knowing that the effects of probiotic bacteria are strain-dependent,... 相似文献
10.
Rafael Fogaça de Almeida Aline Castro Rodrigues Lucena Michel Batista Fabricio Klerynton Marchini Lyris Martins Franco de Godoy 《Proteomics》2023,23(16):2200230
Post-translational methylation of proteins, which occurs in arginines and lysines, modulates several biological processes at different levels of cell signaling. Recently, methylation has been demonstrated in the regulation beyond histones, for example, in the dynamics of protein-protein and protein-nucleic acid interactions. However, the presence and role of non-histone methylation in Trypanosoma cruzi, the etiologic agent of Chagas disease, has not yet been elucidated. Here, we applied mass spectrometry-based-proteomics (LC-MS/MS) to profile the methylproteome of T. cruzi epimastigotes, describing a total of 1252 methyl sites in 824 proteins. Functional enrichment and protein-protein interaction analysis show that protein methylation impacts important biological processes of the parasite, such as translation, RNA and DNA binding, amino acid, and carbohydrate metabolism. In addition, 171 of the methylated proteins were previously reported to bear phosphorylation sites in T. cruzi, including flagellar proteins and RNA binding proteins, indicating that there may be an interplay between these different modifications in non-histone proteins. Our results show that a broad spectrum of functions is affected by methylation in T. cruzi, indicating its potential to impact important processes in the biology of the parasite and other trypanosomes. 相似文献