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111.
Valente CA Prazeres DM Cabral JM Monteiro GA 《Applied and environmental microbiology》2004,70(8):5033-5036
The yield of human alpha 2b interferon in Escherichia coli was optimized by replacement of low-usage arginine codons located in the mRNA 5' end. The differences observed among the various gene variants suggest that codon usage, Shine-Dalgarno-like sequences, and mRNA secondary structure contribute to the performance of E. coli translation machinery. 相似文献
112.
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114.
C Giardina D M Caniglia T Lettini T Valente G Poliseno L Tantimonaco G Favia 《Analytical and quantitative cytology and histology / the International Academy of Cytology [and] American Society of Cytology》2001,23(5):373-380
OBJECTIVE: To search for morphologic nuclear features in the epithelial lining of odontogenic keratocysts to differentiate simple from Gorlin syndrome cysts. STUDY DESIGN: Five cases of syndrome-associated keratocysts and five of simple ones were studied. Thirty nuclei from the epithelial basal layer for each case were analyzed by the shape analytical morphometry (SAM) software system to quantitatively evaluate nuclear dimensions (area, perimeter, diameter), contour irregularities and nuclear shape asymmetries. Results were subjected to Student's t test and cluster analysis. RESULTS: Values of nuclear dimensions were very close in both groups of keratocysts, without any significant statistical differences. The variables related to nuclear profile irregularities, as well as those describing nuclear asymmetry, showed significantly higher values (P < .001) in syndromic cysts. Cluster analysis produced two different clusters by using variables related to nuclear contour irregularities. CONCLUSION: Preliminary results indicate the existence of nuclear morphologic differences between simple and syndromic cysts. 相似文献
115.
S. D. C. Mendes M. Ramírez-Castrillón N. P. Feldberg F. C. Bertoldi P. Valente 《World journal of microbiology & biotechnology》2017,33(6):128
Yeasts were isolated from three vineyards located in the South Region of Brazil. A cross evaluation was carried out at the oldest vineyard of the study in Pinheiro Preto. Samples of grape berries, grapevine leaves and the soil, along with samples of the winery equipment and effluent, were collected. In the Serra do Marari and Campos Novos vineyards only samples of grape clusters were obtained. The 106 yeast isolates were identified by sequencing the D1/D2 domain of LSU rDNA or ITS1-5.8S-ITS2 region in 22 species. The values for the richness indices varied between the vineyards. A comparison of the taxonomic diversity of the yeasts from these regions using the reciprocal Simpson index showed a significant difference between the Serra do Marari and Campos Novos vineyards (5.72?±?0.36 and 2.92?±?0.36, respectively, p?<?0.0001). The functional diversity was assessed in relation to the use of carbon and nitrogen sources by the yeasts isolated from each location. In general, we observed that the Pinheiro Preto and Campos Novos vineyards differed consistently from the Serra do Marari vineyard according to these indices (FAD2, FDc and Rao, p?<?0.0001). The possible spreading of Saccharomyces cerevisiae from the winery to the vineyard in Pinheiro Preto was observed. 相似文献
116.
Mai A Perrone A Nebbioso A Rotili D Valente S Tardugno M Massa S De Bellis F Altucci L 《Bioorganic & medicinal chemistry letters》2008,18(8):2530-2535
A novel series of non-hydroxamate HDAC inhibitors (HDACi) showing a uracil group at the left and a 2-aminoanilide/2-aminoanilide-like portion at the right head have been reported. In particular, the new compounds incorporating a 2-aminoanilide moiety behaved as class I-selective HDACi. Compound 8, the most potent and class I-selective, showed weak apoptosis (higher than MS-275) joined to cytodifferentiating activity on U937 cells. Surprisingly, the highest differentiation was observed with 13, through an effect that seems to be unrelated to HDAC inhibition. 相似文献
117.
P. Silva † L. M. P. Valente † M. Olmedo ‡ M. H. Galante † R. A. F. Monteiro † E. Rocha †§ 《Journal of fish biology》2009,74(1):37-53
To understand better the growth mechanisms in the economically important fish Pagellus bogaraveo, in terms of muscle fibre hyperplasia v. hypertrophy, the lateral muscle of this fish was studied morphometrically from hatching to juvenile comparing rostral and caudal locations. Fish were sampled at 0, 5, 23, 40, 70, 100, 140 and 180 days. Fibre types were first identified by succinate dehydrogenase (SDH) and immunostaining with a polyclonal antibody against fish slow myosin (4–96). Morphometric variables were then measured in transverse body sections, at both post‐opercular and post‐anal locations, to estimate the following variables: total muscle area [A (muscle)], total fibre number [N (fibres)], fibre number per unit area of muscle [NA(fibres, muscle)] and cross‐sectional fibre area [ (fibres)] of the two main muscle fibre types (white and red). Overall, growth throughout the various stages resulted from increases both in the number and in the size of muscle fibres, paralleled by an expansion of the [A (muscle)]. Nonetheless, that increase was not significant between 0–5 days on one hand and 100–140 days, on the other hand. On the contrary, the [NA(fibres, muscle)] declined as the body length increased. Analysis of the muscle growth kinetics suggested that, within the important time frame studied, hyperplasia gave the main relative contribution to the increase of white muscle [A (white muscle)], whereas red muscle [A (red muscle)] mainly grew by hypertrophy, with both phenomena occurring at a faster pace posteriorly in the body. Finally, when comparing rostral and caudal locations, a greater [N (fibres)] and [A (muscle)] of the posterior white and red fibres were the consistent features. It was also observed that the proportion of the cross‐sectional area of the myotomal muscle comprised of white muscle was greater in the anterior part of the fish. 相似文献
118.
ZHENZHEN YI WEIBO SONG THORSTEN STOECK KHALED A. S. AL‐RASHEID ABDULAZIZ A. AL‐KHEDHAIRY JUN GONG HONGWEI MA ZIGUI CHEN 《Zoological Journal of the Linnean Society》2009,157(2):227-236
The morphologically unique ciliate Psammomitra has long been considered as a systematically uncertain stichotrich. This is mainly because of its highly specialized morphology and a lack of either detailed information concerning its ontogenesis, or molecular data. Based on the small subunit rRNA (SSrRNA) gene and alpha‐tubulin gene sequences, we re‐evaluated the phylogenetic position of Psammomitra retractilis using multiple algorithms. Phylogenetic trees inferred from the SSrRNA gene sequences representing a total of 53 spirotrichs demonstrated the closest relationship of Psammomitra was with Holosticha‐like taxa, with strong support, which clearly suggested that Psammomitra should be placed into the order Urostylida although it branched at a rather deep level, and is likely to be closely related to Holostichidae. With consideration to molecular evidence and morphological characters, Psammomitra should be a clearly outlined taxon at about the rank of family, i.e. Psammomitridae stat. nov. , within the order Urostylida. The improved diagnosis for this family is as follows: Urostylida possessing extremely contractile, elongated body which consists of three parts: head, trunk, and slender tail; midventral complex composed of midventral pairs only and restricted to about anterior 1/3 of ventral surface; frontal, frontoterminal, and transverse cirri present; one left and one right marginal rows which commence near proximal end of adoral zone and extend to near rear body end. 相似文献
119.
Carlos García-Estrada Inmaculada Vaca Ricardo V Ullán Marco A van den Berg Roel AL Bovenberg Juan Francisco Martín 《BMC microbiology》2009,9(1):104-15
Background
Penicillium chrysogenum converts isopenicillin N (IPN) into hydrophobic penicillins by means of the peroxisomal IPN acyltransferase (IAT), which is encoded by the penDE gene. In silico analysis of the P. chrysogenum genome revealed the presence of a gene, Pc13g09140, initially described as paralogue of the IAT-encoding penDE gene. We have termed this gene ial because it encodes a protein with high similarity to IAT (IAL for IAT-Like). We have conducted an investigation to characterize the ial gene and to determine the role of the IAL protein in the penicillin biosynthetic pathway. 相似文献120.
Maia LF Soares MR Valente AP Almeida FC Oliveira AC Gomes AM Freitas MS Schneemann A Johnson JE Silva JL 《The Journal of biological chemistry》2006,281(39):29278-29286
The gamma(1)-peptide is a 21-residue lipid-binding domain from the non-enveloped Flock House virus (FHV). Unlike enveloped viruses, the entry of non-enveloped viruses into cells is believed to occur without membrane fusion. In this study, we performed NMR experiments to establish the solution structure of a membrane-binding peptide from a small non-enveloped icosahedral virus. The three-dimensional structure of the FHV gamma(1)-domain was determined at pH 6.5 and 4.0 in a hydrophobic environment. The secondary and tertiary structures were evaluated in the context of the capacity of the peptide for permeabilizing membrane vesicles of different lipid composition, as measured by fluorescence assays. At both pH values, the peptide has a kinked structure, similar to the fusion domain from the enveloped viruses. The secondary structure was similar in three different hydrophobic environments as follows: water/trifluoroethanol, SDS, and membrane vesicles of different compositions. The ability of the peptide to induce vesicle leakage was highly dependent on the membrane composition. Although the gamma-peptide shares some structural properties to fusion domains of enveloped viruses, it did not induce membrane fusion. Our results suggest that small protein components such as the gamma-peptide in nodaviruses (such as FHV) and VP4 in picornaviruses have a crucial role in conducting nucleic acids through cellular membranes and that their structures resemble the fusion domains of membrane proteins from enveloped viruses. 相似文献