Thermoluminescence emission on lead oxychloroborate glasses under UV exposure.

Glassy materials were prepared using two different systems: 50B2 O3 - (50 - x)PbO - xPbCl2, with x = 0, 2 and 5 in mol % (System BPCl-I) and 50BO1.5 - (50 - x)PbO - xPbCl2 with x = 0, 2, 5 and 7 in cationic % (System BPCl-II). Structural and optical characterization showed that PbCl when substituted for PbO changed the structure of the glass network by replacing nonbridging oxygens for chlorine ions. This substitution also caused a change in the number of defects responsible for thermoluminescence (TL) emission (electrons and hole trap centres). Thermoluminescence emissions were observed for the first time in lead oxychloroborate glasses after exposure to UV radiation. Sample BPCl-I-2 (x = 2 from System I) demonstrated better TL emission compared with other glass samples. One intense peak in the glow curve, centred at ~122°C followed by a shoulder at ~180°C, was highly sensitive to UV radiation. There were also good linear responses at dose range ~0.4 to ~2 J/cm2 for the first peak (low temperature) and ~0.4 to ~4 J/cm2 for the second peak (high temperature).

Bioinformatics construction of the human cell surfaceome.

Cell surface proteins are excellent targets for diagnostic and therapeutic interventions. By using bioinformatics tools, we generated a catalog of 3,702 transmembrane proteins located at the surface of human cells (human cell surfaceome). We explored the genetic diversity of the human cell surfaceome at different levels, including the distribution of polymorphisms, conservation among eukaryotic species, and patterns of gene expression. By integrating expression information from a variety of sources, we were able to identify surfaceome genes with a restricted expression in normal tissues and/or differential expression in tumors, important characteristics for putative tumor targets. A high-throughput and efficient quantitative real-time PCR approach was used to validate 593 surfaceome genes selected on the basis of their expression pattern in normal and tumor samples. A number of candidates were identified as potential diagnostic and therapeutic targets for colorectal tumors and glioblastoma. Several candidate genes were also identified as coding for cell surface cancer/testis antigens. The human cell surfaceome will serve as a reference for further studies aimed at characterizing tumor targets at the surface of human cells.

Dissimilar peptidase production by avirulent and virulent promastigotes of Leishmania braziliensis: inference on the parasite proliferation and interaction with macrophages.

In the present paper, we have analysed the cellular and extracellular proteolytic activity profiles in 2 distinct Leishmania braziliensis strains: a recently isolated (virulent) and a laboratory-adapted (avirulent) strain. Quantitative and qualitative differences on the peptidase expression were observed in both strains. For instance, low-molecular mass acidic cysteine peptidase activities were detected exclusively in the virulent strain. Similarly, metallopeptidase activities were mainly produced by L. braziliensis virulent promastigotes. Interestingly, metallo- and cysteine peptidase activities were drastically reduced after several in vitro passages of the virulent strain. Western blotting, flow cytometry and fluorescence microscopy analyses were performed to detect homologous of the major leishmania metallopeptidase (gp63) and cysteine peptidase (cpb) in virulent and avirulent strains of L. braziliensis. Our results revealed that the virulent strain produced higher amounts of gp63 and cpb molecules, detected both in the surface and cytoplasm regions, than the avirulent counterpart. Metallo- (1,10-phenanthroline and EGTA) and cysteine peptidase (E-64) inhibitors arrested the growth of L. braziliensis virulent strain in a dose-dependent manner, as well as the association index with peritoneal murine macrophages. Conversely, these peptidase inhibitors did not affect either the proliferation or the cellular interaction of the avirulent strain. Corroborating these findings, the pre-treatment of the virulent strain with both anti-peptidase antibodies promoted a prominent reduction in the interaction with macrophages, while the association index of the avirulent strain to macrophage was only slightly diminished. Moreover, the spent culture medium from virulent strain significantly enhanced the association index between avirulent strain and macrophages, and this effect was reversed by 1,10-phenanthroline. Collectively, the results presented herein suggest that peptidases participate in several crucial processes of L. braziliensis.

Avaliação técnica e econômica de diferentes grupos genéticos de bovinos de corte machos superprecoces e do sistema de produção em confinamento / Technical and economic evaluations of different genetic groups of yearling beef cattle males and of the feedlot production system

Avaliaram-se as variáveis técnicas e econômicas do sistema de produção em confinamento de 88 animais superprecoces (sete meses de idade) pertencentes a três grupos genéticos, com 23 animais Charolês x Nelore, 26 Red Angus x Nelore e 39 Abeerden Angus x Nelore. Foram registrados pesos no inicio do confinamento e ao abate, duração do confinamento, ganhos de peso no período e diário dos animais e, por meio de conceitos econômicos e operacionais, foram calculados os custos de produção. O modelo estatístico utilizado na análise das variáveis incluiu efeitos do grupo genético e do peso inicial como covariável. Não houve diferença entre grupos genéticos para peso ao abate e ganho de peso diário. A duração do confinamento foi menor para animais Charolês x Nelore (159 dias), intermediária para Red Angus x Nelore (170 dias) e maior para Abeerden Angus x Nelore (178 dias). Os custos total, operacional e variável da diária foram 1,02; 0,85 e 0,89 US$/dia, respectivamente. O confinador obteve lucro de 0,01 US$/kg e rentabilidade de 1,8 por cento/mês. Não houve diferenças (P>0,05) entre grupos genéticos para custos, receita, margens bruta e líquida, lucro e rentabilidade.

This experiment was carried out to evaluate technical and economic parameters for feedlot production system of 88 seven-month-old animals of three genetic groups (23 Charolais x Nellore, 26 Red Angus x Nellore, and 39 Aberdeen Angus x Nellore). Production traits (initial and slaughtering weights, number of days in feedlot, and total and daily weight gains) were recorded and costs were estimated using operational and economic concepts. The statistical model used to analyze the traits included the fix effect of genetic group and initial body weight as a covariate. No differences were observed among the genetic groups for slaughtering weight and daily weight gain. Number of days in feedlot was low for Charolais x Nellore (159 days), intermediate for Red Angus x Nellore (170 days), and high for Aberdeen Angus x Nellore (178 days) animals. Total, operational, and variable costs were 1.02; 0.85; and 0.89 US$/day. Farmer profit was 0.01 US$/kg and profitability/month was 1.78 percent. Significant differences among the genetic groups were not observed for cost, income, gross and net margins, profit, and profitability.

Critérios de seleção para características de crescimento em bovinos da raça Nelore / Selection criteria for growth traits in Nellore cattle

Foram utilizados 28.050 registros de bovinos Nelore para estabelecer critérios de seleção para bovinos de corte, considerando as características ganho médio diário do nascimento à desmama (GND), dias para o animal ganhar 160kg do nascimento à desmama (D160), ganho médio diário da desmama ao sobreano (D240) e dias para o animal ganhar 240kg da desmama ao sobreano (D240). As estimativas de herdabilidade foram: GND, 0,20; D160, 0,19; GDS, 0,07; e D240, 0,03. Considerando os efeitos maternos, a herdabilidade da característica D160 foi 0,16 e a da GND, 0,06. Verificou-se correlação genética alta e negativa entre GND e D160 (-0,95) e negativas entre efeito genético direto do GND e efeito genético materno da mesma característica (-0,24) e entre efeitos genéticos diretos do GND e do D160 (-0,15). Houve associação positiva entre o efeito genético materno de GND e direto de GDS (0,33), e correlação nula entre o efeito genético direto das características D160 e D240. Conclui-se que a velocidade de crescimento pode ser modificada adotando-se como critério de seleção qualquer uma das duas características do período pré-desmama, apesar deles não selecionarem os mesmos animais, principalmente se na adoção do critério forem considerados os efeitos maternos no período pré-desmama e os efeitos genéticos diretos no período pós-desmama. As magnitudes das correlações estimadas entre as características nos períodos pré e pós-desmama foram baixas, indicando que os animais poderiam ser selecionados no período pré-desmama, independente do critério de seleção adotado na pós-desmama.

pp-Blast: a "pseudo-parallel" Blast.

We have developed a software called pp-Blast that uses the publicly available Blast package and PVM (parallel virtual machine) to partition a multi-sequence query across a set of nodes with replicated or shared databases. Benchmark tests show that pp-Blast running in a cluster of 14 PCs outperformed conventional Blast running in large servers. In addition, using pp-Blast and the cluster we were able to map all human cDNAs onto the draft of the human genome in less than 6 days. We propose here that the cost/benefit ratio of pp-Blast makes it appropriate for large-scale sequence analysis. The source code and configuration files for pp-Blast are available at http://www.ludwig.org.br/biocomp/tools/pp-blast.

pp-Blast: a "pseudo-parallel" Blast

We have developed a software called pp-Blast that uses the publicly available Blast package and PVM (parallel virtual machine) to partition a multi-sequence query across a set of nodes with replicated or shared databases. Benchmark tests show that pp-Blast running in a cluster of 14 PCs outperformed conventional Blast running in large servers. In addition, using pp-Blast and the cluster we were able to map all human cDNAs onto the draft of the human genome in less than 6 days. We propose here that the cost/benefit ratio of pp-Blast makes it appropriate for large-scale sequence analysis. The source code and configuration files for pp-Blast are available at http://www.ludwig.org.br/biocomp/tools/pp-blast

ExInt: an Exon Intron Database.

The Exon/Intron Database (ExInt) stores information of all GenBank eukaryotic entries containing an annotated intron sequence. Data are available through a retrieval system, as flat-files and as a MySQL dump file. In this report we discuss several implementations added to ExInt, which is accessible at http://intron.bic.nus.edu.sg/exint/newexint/exint.html.

Transcatheter embolization of congenital coronary arterial fistulas in adults.

In this report, we describe our experience with transcatheter occlusion of congenital coronary arterial fistulas in adults. From November 1992 to November 1996, 5 symptomatic patients, aged from 47 to 70 years, underwent transcatheter occlusion of fistulas using a retrograde arterial approach. All had chest pain or dyspnea on exertion. Detachable balloons were used in 4 patients, and Gianturco coils in 1. Detachable balloons were implanted through a Debrun system, while the coils were implanted through a 5 French right coronary Judkins catheter. Both were passed through an 8 French guiding catheter (Amplatz II). Each patient had a single fistula. The fistulas originated from the right coronary artery in 3 patients, and from the circumflex artery in 2. They drained into the pulmonary trunk in 3 patients, into the right atrium in 1, and into a bronchial artery in the other. All fistulas were occluded completely in the catheterization laboratory, and the procedures were uncomplicated. At follow up, 3 patients underwent coronary angiography, and there was no evidence of recanalization. Transcatheter embolization in adults of single congenital coronary fistulas with detachable balloons and coils is safe and effective and can be regarded as an acceptable alternative to surgery.

Stannous chloride and the glucoheptonic acid effect: study of a kit used in nuclear medicine.

Stannous dichloride is used as a reducing agent in the preparation of technetium-99m radiopharmaceuticals. We decided to evaluate the genotoxic potential of the tin (II)-glucoheptonate complex in the kit using a tester strain of Escherichia coli AB1157. Our results show that tin (II) chloride and the tin (II)-glucoheptonate complex exert a genotoxic effect in this system. While the genotoxic effect disappeared when the glucoheptonate concentration was increased, the glucoheptonate did not protect the cultures from the damaging effects of hydrogen peroxide. The ability of glucoheptonate to protect cultures from tin (II)-induced damage can be explained on the basis of its metal chelating properties.

Cross-sectional configuration of endodontic files compared with manufacturers' design.

The cross-sectional configuration of seven files at coronal and apical levels were compared with diagrams presented by manufacturers. The presence of cutting edges was also examined. Ground-twisted (K-file, K-Reamer, and K-flex) and machined files (Flex-R, Unifile, S-file, and Hedstrom) were included in #10, #25, and #40. Twelve files of each size and brand comprised the samples. Files were embedded in acrylic, which was then cut in cross-section in the apical and coronal parts of the flutes. These were photographed under a microscope. Six clinicians viewed the slides projected onto a screen for comparison with manufacturers' design and evaluation of visible cutting edges. The inconsistencies were primarily in machined files, smaller sizes, and apical sections of the instruments. Data showed that overall the cross-sections and presence of cutting edges compared well with the designs intended by the manufacturers.

Laser-assisted fibrinogen bonding of umbilical vein grafts.

Despite success with autologous tissue welding, laser welding of synthetic vascular prostheses has not been possible. The graft material appears inert and fails to allow the collagen breakdown and electrostatic bonding that results in tissue welding. To develop a laser welding system for graft material, we repaired glutaraldehyde-tanned human umbilical cord vein graft incisions using laser-assisted fibrinogen bonding (LAFB) technology. Modified umbilical vein graft was incised transversely (1.2 cm). Incisions were repaired using sutures, laser energy alone, or LAFB. For LAFB, indocyanine green dye was mixed with human fibrinogen and the compound applied with forceps onto the weld site prior to exposure to 808 nm diode laser energy (power density 4.8 W/cm 2). Bursting pressures for sutured repairs (126.6 +/- 23.4 mm Hg) were similar to LAFB anastomoses (111.6 +/- 55.0 mm Hg). No evidence of collateral thermal injury to the graft material was noted. In vivo evaluation of umbilical graft bonding with canine arteries demonstrates that LAFB can reliably reinforce sutured anastomoses. The described system for bonding graft material with laser exposed fibrinogen may allow creation or reinforcement of vascular anastomoses in procedures where use of autologous tissue is not feasible.

Endodontic treatment of a maxillary lateral incisor presenting dens invaginatus and transposition to the region of the canine--case report.

Endodontic treatment was performed in a maxillary lateral incisor presenting two different types of anomalies: dens invaginatus and transposition to the region of the canine. The two transposed teeth were subsequently restored with light-cured composite, bringing dental esthetics to normal in a single session.

Periodontal ligament injection: an evaluation of the extent of anesthesia and postinjection discomfort.

The effects of a periodontal ligament (PDL) injection were evaluated as to whether the injected tooth alone or adjacent teeth were anesthetized. Results of the study indicated no difference in anesthesia achieved from pistol-pressure or standard-grip syringes, and determined what effects the type of syringe and solution injected had on the spread of anesthesia and the degree of discomfort felt during and after the injection.