Biomedical subjects

G Vieira

Publications and source records attributed to G Vieira.

12 recordsLinked to original sources

PubMed2003

Anti-inflammatory effect of Solanum lycocarpum fruits.

The croton oil-induced mouse ear oedema test, acetic acid-induced abdominal writhing, and carrageenan-induced peritonitis were used to study the anti-inflammatory effects of the crude ethanol extract and its alkaloid fraction from Solanum lycocarpum fruits. The alkaloid fraction induced a dose-dependent reduction in ear oedema formation and leukocyte migration, suggesting that S. lycocarpum fruits may contain steroidal alkaloids accounting for the anti-inflammatory effect of the crude ethanol extract.

Acetic Acid↗

PubMed2001

Leaf gas exchange and carbohydrates in tropical trees differing in successional status in two light environments in central Amazonia.

Monoculture and mixed stands of mahogany (Swietenia macrophylla King) and tonka bean (Dipteryx odorata Willd.) trees were established on degraded land in central Amazonia to compare leaf gas exchange parameters between plants grown in sunlight in an open field and in shade beneath a balsa wood (Ochroma pyramidale Cav.) canopy. Shading increased specific leaf area by about 50% in both species. Shading reduced height and diameter growth of S. macrophylla, whereas it increased these parameters for D. odorata. Light-saturated photosynthesis (Amax), stomatal conductance (gs) and transpiration (E) were higher in S. macrophylla than in D. odorata. In S. macrophylla, Amax was higher in sun leaves (12.9 +/- 0.9 micromol m-2 s-1) than in shade leaves (10.2 +/- 1.0 micromol m-2 s-1), whereas light environment had no significant effect on Amax of D. odorata. In both species, CO2-saturated photosynthesis (Apot) was higher in sun leaves (22 +/- 1.4 micromol m-2 s-1) than in shade leaves (17-20 +/- 0.8 micromol m-2 s-1). Stomatal conductance and E increased in sun leaves of S. macrophylla by 45 and 38%, respectively, whereas light environment did not affect gs and E of D. odorata. Photorespiration rates (Pr) varied from 28 to 36% of net photosynthesis (A) at ambient atmospheric CO2 concentration (Ca) but declined to around 7% of A at higher Ca. Leaf dark respiration (Rd) and the CO2 compensation point (Gamma) were lower in shade-grown plants than in open-grown plants. Compared with shade-grown plants, total nonstructural carbohydrate (TNC) concentrations increased by 56% in S. macrophylla and by 30% in D. odorata in the open field. Leaf nitrogen (NL) concentrations were higher in open-grown plants than in shade-grown plants of both species, and TNC and NL concentrations were negatively correlated (r = -0.77). High TNC accumulation in S. macrophylla in the open field suggests that photosynthesis is unlikely to be growth-limiting at this site. We conclude that photosynthetic parameters of D. odorata are less affected by light environment than those of S. macrophylla, indicating that D. odorata has lower physiological plasticity to light than S. macrophylla.

Brazil↗

PubMed2000

The N-terminal region of the Oenococcus oeni bacteriophage fOg44 lysin behaves as a bona fide signal peptide in Escherichia coli and as a cis-inhibitory element, preventing lytic activity on oenococcal cells.

The function of the N-terminal region of the Oenococcus oeni phage fOg44 lysin (Lys44) as an export signal was investigated. We observed that when induced in Escherichia coli, Lys44 was cleaved between residues 27 and 28 in a SecA-dependent manner. Lys44 processing could be blocked by a specific signal peptidase inhibitor and was severely reduced by modification of the cleavage site. The lethal effect of Lys44 expression observed in E. coli was ascribed to the presence of its N-terminal 27-residue sequence, as its deletion resulted in the production of a nontoxic, albeit active, product. We have further established that lytic activity in oenococcal cells was dependent on Lys44 processing. An active protein with the molecular mass expected for the cleaved enzyme was detected in extracts from O. oeni-infected cells. The temporal pattern of its appearance suggests that synthesis and export of Lys44 in the infected host progress along with phage maturation. Overall, these results provide, for the first time, experimental evidence for the presence of a signal peptide in a bacteriophage lysin. Database searches and alignment of protein sequences support the prediction that other known O. oeni and Lactococcus lactis phages also encode secretory lysins. The evolutionary significance of a putative phage lysis mechanism relying on secretory lytic enzymes is tentatively discussed, on the basis of host cell wall structure and autolytic capacity.

Amino Acid Sequence↗

PubMed2000

[Application of the Portuguese version of the abbreviated instrument of quality life WHOQOL-bref].

INTRODUCTION: The need of short instruments to evaluate Quality of life determines World Health Organization Quality of Life Group (WHOQOL Group) to develop an abbreviated version of the WHOQOL-100, the WHOQOL-bref. The objective is to present the Brazilian field trial of the WHOQOL-bref. METHODS: WHOQOL-bref is composed by 26 questions divided in four domains: physical, psychological, social relationships and environment. The evaliation instrument, BDI (beck depression inventory) and BHS (beck hopelessness scale) were used in a 300 subjects sample in Porto Alegre, South Brazil. RESULTS/CONCLUSIONS: The instrument showed a good performance concerning internal consistency, discriminant validity, criterion validity, concurrent validity and test-retest reliability. The intrument allies good psychometric performance and practicity for use which puts it as an interesting option to evaluate quality of life in Brazil.

Brazil↗

PubMed1999

Gene organization in a central DNA fragment of Oenococcus oeni bacteriophage fOg44 encoding lytic, integrative and non-essential functions.

The nucleotide sequence of a DNA fragment previously shown to contain the attachment site (attP) of Oenococcus oeni phage fOg44 (. Arch. Virol. 143, 523-536) has been determined. Sequence analysis indicated that this 6226bp EcoRI fragment harbours an integrase gene, in the vicinity of a direct repeat rich region defining attP, as well as genes encoding a muramidase-related lysin (Lys) and a holin polypeptide (Hol). Transcriptional studies suggested that lys and hol are mainly co-expressed, late in the lytic cycle, from a promotor located upstream of lys. Between the lytic cassette and the phage integration elements three additional open reading frames were found: orf217 and orf252 of unknown function and orf72, the putative product of which bears 32% identity with acidic excisionases from other Gram positive phages. We have established that the first two orfs, as well as the predicted promotor of orf72, are included in a 2143-bp DNA segment missing from the genome of the deletion mutant fOg44Delta2. Although lysogens of fOg44 and fOg44Delta2 exhibited similar properties, each phage produced two distinguishable types of lysogenic strains, differing in inducibility and immunity to other oenophages.

Amino Acid Sequence↗

PubMed1999

[Application of the Portuguese version of the instrument for the assessment of quality of life of the World Health Organization (WHOQOL-100)].

OBJECTIVE: The WHOQOL group have developed an instrument to evaluate Quality of Life, the WHOQOL-100, available in 20 different languages (WHOQOL Group, 1998). The field trial of the portuguese version of the instrument is presented. METHODS: Two hundred and fifty patients from four main medical areas (Psychiatry, Clinical, Surgery and Ginecology) of the Hospital de Clínicas de Porto Alegre and 50 controls were evaluated with the Portuguese version of the WHO Quality of Life Instrument (WHOQOL-100), Beck Depression Inventory (BDI) and Beck Hopelessness Scale (BHS) in Porto Alegre, south Brazil. RESULTS AND CONCLUSION: The instrument showed a good psychometric performance with good internal consistency, discriminant validity, criterion validity, concurrent validity and reliability. The authors conclude that the intrument is ready for use in Brazil, it being important to evaluate its performance in other regions and with different samples.

Adult↗

PubMed1998

Genome diversity in temperate bacteriophages of Oenococcus oeni.

The genome structure of six bacteriophages of Oenococcus oeni was compared. Two distinct groups with no apparent restriction site conservation were defined. In members of the alpha group (fOgML34, fOg4029, fOg30 and fOg218) a 7.5 kb region containing the origin of DNA packaging (cos) was highly conserved. Stretches of DNA heterogeneity could also be assigned to particular regions and were mostly evident in the right area of the genomes. fOg44 and fOgPSU1 (beta group) were indistinguishable in the left half of their genomes, including cos, but were markedly dissimilar in other regions. Strong labelling signals detected in cross-hybridizations involving members of different groups were confined to fragments centrally located in their physical maps. The attachment site (attP) of fOg44 was assigned to this conserved region. It is suggested that recombination events at this location may have been important in generating the observed diversity of oenophage genomes.

Bacteriophages↗

PubMed1996

Nucleotide sequence analysis of pOg32, a cryptic plasmid from Leuconostoc oenos.

Analysis of the nucleotide sequence of Leuconostoc oenos plasmid pOg32 (2544 bp) revealed three open reading frames (ORFs) in one of the DNA strands preceded by putative promoters and ribosome binding sites. ORF1 corresponded to a polypeptide similar to the replication proteins (Rep) of pT181 plasmid family. A nucleotide sequence like the double strand origin (DSO) of the same plasmid family was found inside the presumptive rep gene. ORF2 is capable of encoding a protein resembling the recombination enzyme (Pre) of two lactobacilli plasmids. Immediately upstream of the presumed pre gene, a sequence similar to the consensus RSA regions of those plasmids was encountered. Between ORF3 and ORF1, a sequence comparable to the RSB consensus region of the single strand origin ssoA was detected. The putative RSB region was located at the 3'-end of an imperfect palindrome which may be a single stranded origin. The described features, common to other small plasmids of Gram-positive bacteria, suggest that pOg32 replicates by the rolling circle mechanism. The amino acid sequence encoded by ORF3 was not similar to any known protein.

Amino Acid Sequence↗

PubMed1994

Inter-strain relationships among wine leuconostocs and their divergence from other Leuconostoc species, as revealed by low frequency restriction fragment analysis of genomic DNA.

Thirty Leuconostoc oenos strains, representing 28 different isolates, were distributed into 20 genomic groups according to PFGE patterns of restriction digests. The 8 bp-specific enzymes Sfi I, Not I and Asc I cleaved the Leuc. oenos DNA in a mean of 17, 11 and four fragments respectively and Sma I produced more than 50 fragments per genome. The strain differentiating capacity of the four enzymes was similar; only two related genomic groups failed to be distinguished by Asc I or Not I. Genomic relationships between Leuc. oenos strains were quantified by numerical analysis of Not I and Sfi I banding patterns. More than half of the strains, including the starters ML34 and PSU-1, formed a major cluster. The average size of the Leuc. oenos genome was estimated as 1.86 Mb. Although similar values were obtained for the genomes of Leuc. mesenteroides, Leuc. pseudomesenteroides, Leuc. gelidum and Leuc. citreum, a significant divergence between wine and non-wine species was inferred from comparisons of genome cleavage frequencies, determined with five different enzymes.

Base Sequence↗

PubMed1993

[Extension of an epidermoid carcinoma of the tongue to the infratemporal fossa].

Based on an atypical case of squamous carcinoma of the tongue in a young non-alcoholic, non-smoking woman, the authors review the anatomy of the tongue and adjacent spaces. The features of extension and the CT and MRI diagnosis of the tumour are analysed. Extension beyond the oropharynx to the pharyngolarynx and intratemporal fossa and bony involvement changed the stage and modified the treatment.

Adult↗

PubMed1989

Restriction analysis of PBS 1-related phages.

The Bacillus subtilis bacteriophages AR 9, 3 NT, and I 10 belong to the same group as the widely used bacteriophage PBS 1. These four phages have in common, among other properties, flagellotropic adsorption to host cells and total substitution of thymine by uracil in their DNAs. We tested the action of different restriction endonucleases on the four genomes. Among 14 enzymes, which did cut the DNAs into discrete fragments, six are known as having at least one thymine residue in their recognition sequences. The electrophoretical patterns of the digested DNAs from the four phages show strong similarities. Nevertheless, the differences are sufficient to allow a clear distinction between them.

Bacillus subtilis↗

PubMedDate not supplied

Phlebectasia within the sural nerve.

During the period of one year, 222 patients were submitted to corrective surgery for varicose veins of the lower limbs; in 170 the short saphenous vein was removed. In ten of the latter patients there was phlebectasia of veins lying within the sural nerve. Intra-operative phlebography showed communicating veins between the area of phlebectasia and the deep venous system. These atypical communicating veins directed the venous flow toward the fibular and posterior tibial veins. The authors discuss the importance of these findings.

Adult↗