Showing papers by "Rio de Janeiro State University published in 1993"

Topical application of fluorides on teeth. New concepts of mechanisms of interaction.

Abstract: Prevention of caries in exposed root surfaces constitutes an important clinical problem. It is thus important that clinicians involved with periodontology have an insight into fluoride prophylaxis. The understanding of the cariostatic mechanism of fluoride has improved during recent years. The aim of the present review is to give a short account of the present concept. Calcium fluoride appears to be the only product which is formed on enamel, dentin or cementum during brief topical treatments with fluoride or use of toothpaste containing fluoride. This calcium fluoride is stable in the oral environment; this is contrary to what was believed until recently. The calcium fluoride constitutes a pH-dependent reservoir of fluoride which releases fluoride when pH drops. The practical consequences of this concept is discussed.

Rat paw edema and leukocyte immigration induced by plant lectins

Abstract: Lectins fromDioclea grandiflora (DG) andCanavalia brasiliensis (CB) were compared with Concanavalin A (ConA) for their ability to induce paw edema and peritoneal cell immigration in rats. ConA caused a slight edema with a peak at 1 h after injection, while DG or CB induced a pronounced and long-lasting edema that reached a maximum at about 6 h. Different antiinflammatory drugs partially inhibited the edema. α-d-glucose (GLU) partially blocked the edema caused by ConA and markedly inhibited that due to CB, but had no effect on the edema induced by DG. α-Methyl mannoside (α-MM) blocked the edema caused by DG and ConA, but did not affect that caused by CB. At doses much lower than those used to induce paw edema, the lectins promoted an intense accumulation of neutrophil and mononuclear cells in the rat peritoneal cavity. CB and DG were more potent than ConA, which also presented a different profile of cell immigration. GLU significantly inhibited leukocyte accumulation caused by all lectins. α-MM impaired ConA- and DG-induced cell immigration, but only partially inhibited CB. Thus, despite their physicochemical similarities with ConA, DG and CB have more powerful pro-inflammatory effects. This difference seems to be related to their sugar-binding properties. However, while ConA- and DG-induced effects were inhibited more by α-MM than by GLU, CB-induced effects were inhibited more by glucose.

Prevalência de consumo de bebidas alcoólicas e de alcoolismo em uma região metropolitana do Brasil

Abstract: Foi realizado Inquerito epidemiologico com o objetivo de estimar o uso de substâncias psicoativas e a prevalencia de alcoolismo. Tomou-se como referencia a populacao de maiores de 13 anos de idade de regiao administrativa da cidade do Rio de Janeiro, RJ (Brasil), da qual se extraiu uma amostra aleatoria de 1.459 individuos. Os resultados referentes ao uso de bebidas alcoolicas e alcoolismo, identificados atraves do teste CAGE, mostraram: prevalencia de 51% para o consumo de alcool e de 3% para alcoolismo, sendo 4,9% em homens e 1,7% em mulheres; maior proporcao de consumidores de alcool e de alcoolistas entre homens de 30 e 49 anos; abstinencia mais frequente entre os viuvos, protestantes e individuos com niveis de renda inferiores.

Activity patterns and body temperatures of two sympatric lizards (Tropidurus torquatus and Cnemidophorus ocellifer) with different foraging tactics in southeastern Brazil

Abstract: Nos estudamos a biologia termal e comparamos os padroes termais e de atividade de dois lagartos simpatricos com diferentes taticas de forrageamento (Tropidurus torquatus e Cnemidophorus ocellifer) num habitat de restinga na Reserva Florestal Vale do Rio Doce, Linhares, Brasil. Os dados mostraram que as temperaturas corporais de ambas as especies relacionaram-se positiva e significativamente com a temperatura do substrato. A especie forrageadora ativa, C. ocellifer, teve temperaturas medias corporais significativamente maiores (37.6 ± 2.0°C) do que o senta-e-espera T. torquatus (35.6 ± 1.9°C), e permaneceu ativo no habitat numa porcao menor de tempo (entre 8:30 e 15:00 h) do que T. torquatus (entre 7:00 e 18:00 h). Nossos resultados estao de acordo com a premissa de que especies forrageadoras ativas teriam maiores temperaturas medias corporais e permaneceriam ativas no habitat por periodo de tempo relativamente mais curto do que especies forrageadoras sedentarias.

Proportional analysis of the kidney arterial segments

Abstract: The proportional area of each renal arterial segment was analyzed in 49 polyester resin corrosion endocasts of the renal vasculature. We defined a segmental artery as a primary or secondary branch of the renal artery that could be isolated outside the hilum. We found kidneys with five arterial segments in 30 of 49 casts (61.2% of cases) and kidneys with four arterial segments in 19 of 49 casts (38.8%). To enable the evaluation of the proportional areas of the autonomous segments (by using the "point-counting planimetry method"), each arterial segmental branch was injected with different-colored resin. The superior segment (apical) was present in 36 of 49 casts (73.5% of cases) and had a median proportional area of 13.02%. The anterosuperior and anteroinferior segments were present in 30 of 40 casts (61.2% of cases) and had median proportional areas of 21.36% and 17.18%, respectively. The anterior segment was present in 19 of 49 casts (38.8% of cases; when the mid-kidney anterior surface received only one segmental artery) and had a median proportional area of 28.44%. The inferior segment was present in 100% of cases and had a median proportional area of 22.65%. The posterior segment was also present in 100% of cases and was the segment with the greatest median proportional area (33.76%).

Saúde e trabalho de mulheres profissionais de enfermagem em um hospital público de Salvador, Bahia

Abstract: O trabalho de Enfermagem, desenvolvido essencialmente por mulheres, envolve numerosos fatores de risco para a saude. Apesar disso, no Brasil, os estudos sobre a saude desse grupo ocupacional praticamente inexistem. Este estudo transversal pretendeu diagnosticar as condic;:oes de saude e trabalho de enfermeiras e auxiliares de enfermagem em urn grande hospital publico. Foram realizadas entrevistas e medidas de peso, altura e pressao arterial no proprio local de trabalho, em 497 trabalhadoras. Especialmente nas auxiliares, foram encontradas altas prevahncias de problemas agudos (45%), e cronicos como dores de coluna (71%), varizes (57,5%),hipertensao arterial (24,9%), transtomos menta is (36,7%), obesidade (16%), problemas digestivos (34,5%) e respiratorios (31 %). Ambos os grupos apresentam excessivas jornadas de trablho profissional. Contudo, as auxiliares sao duplamente penalizadas pelo acumulo de trabalho domestico, 0 que contribui para suas piores condicoes de saude.

Pseudomonas aeruginosa binds to soluble cellular fibronectin

Abstract: We have investigatedPseudomonas aeruginosa binding to plasma and cellular fibronectin (FN), in both their soluble and insoluble forms. Bacterial binding to insoluble FN was studied by exposing coverslips coated with FN to radiolabeled microorganisms.P. aeruginosa binding to soluble FN was investigated (1) by comparing radiolabeled bacteria treated with FN with PBS-treated bacteria in their adhesion to a collagen matrix; (2) by analyzing the reactivity ofP. aeruginosa with plasma or cellular FN adsorbed to gold particles with transmission electron microscopy (TEM).P. aeruginosa did not bind significantly to insoluble plasma or cellular FN, or to soluble plasma FN. In contrast, bacterial treatment with soluble cellular FN significantly increased the adhesion to the collagen matrix. With TEM, we confirmed the reactivity ofP. aeruginosa with soluble cellular FN. Because there is a marked secretion of cellular FN during wound repair, we speculate that this reactivity may account for the propensity ofP. aeruginosa to infect repairing tissues.

Identification of GTPase genes in the protozoa parasites Trypanosoma cruzi and Leishmania amazonensis.

Abstract: A PCR based assay was designed in order to amplify putative ras gene sequences of the GTPase superfamily eventually present in Leishmania amazonensis and Trypanosoma cruzi. A set of primers corresponding to the conserved motifs G1 and G3 of the GTP binding proteins was synthesized. Sequencing of six PCR products (three from Leishmania and three from Trypanosoma) identified, however, two other different GTPases. The 270 bp L. amazonensis clone, pLef-11, shared an amino acid identity of around 80% with an eukaryotic elongation factor 1a of protein synthesis. On the other hand, the 168 bp T. cruzi clone, pTCr1, demonstrated over 60% amino acid identity to ras-related proteins of the rab-YPT-SEC4 family involved in control of vesicular traffic. To our knowledge, this is the first report of GTP binding protein genes in trypanosomatids.

Effect of various digestive enzymes on the interaction of Toxoplasma gondii with macrophages

Abstract: The participation of resident, elicited, and activated macrophage surface components during internalization of tachyzoites ofToxoplasma gondii was analyzed using neuraminidase, phospholipase C, trypsin, protease, and hyaluronidase. Treatment of these macrophages with neuraminidase fromVibrio cholerae, phospholipase C fromBacillus cereus andClostridium perfringens, protease, and hyaluronidase prior to their interaction with parasites increased the penetration of host cells byT. gondii. Incubation of macrophages with trypsin significantly inhibited the uptake of parasites. Our findings confirm previous observations that treatment of the macrophages with cytochalasin D under conditions that completely block the typical phagocytic process partially inhibits infection of the cells byT. gondii. The results of simultaneous treatment of the macrophages with enzymes and cytochalasin D suggested that the observed enhancement of cell infection by treatment with neuraminidase and hyaluronidase was attributable to a classic phagocytic process, whereas that obtained using phospholipase resulted from active penetration.

Direct bonded space maintainers.

Abstract: The aim of this study was to evaluate clinically a bonded space maintainer, which would reduce chair-side time and cost. Sixty appliances were fabricated from 0.7 mm stainless steel round wire and bonded using light-cured composite to the two teeth adjacent to the site of extraction of a posterior primary tooth. Twenty males and sixteen females (age range 5-9-years-old) were selected from the Pedodontic clinic of the State University of Rio de Janeiro. The sixty space maintainers were divided into two groups according to the site in which they were placed: a) absent first primary molar and b) absent second primary molar. Impressions and study models were obtained prior to and 6 months after bonding the appliances. During this period only 8.3% of failures were observed, most of them from occlusal or facial trauma. Student t-test did not show statistically significant alterations in the sizes of the maintained spaces during the trial period.

Role of drug injection in the spread of HIV in Argentina and Brazil.

Abstract: AIDS cases attributable to using contaminated needles in nonmedicinal drug injection have increased in Argentina from 11.3% in 1987 to 39% in 1991. A similar increase (from 1.8% in 1985 to over 30% in 1991) occurred in Brazil. To complement existing information data searches were conducted and personal communications from current researchers were collected for a total of 24 documents from Argentina and 18 from Brazil. The median sample size was 68 in Brazil and 188 in Argentina; most studies were from outpatient facilities males constituted more than two-thirds of the sample in half of the studies and the median age (when reported) was between 16 and 29 years old. Analysis of data from selected studies showed that HIV seroprevalence among drug injectors in both countries has increased rapidly with the greatest increase occurring in Brazil. This rapid increase may also be influenced by the fact that cocaine rather than heroin is the drug of choice. Cocaine injection involves drawing blood into the syringe before injection and also more frequent injections. The level of seroprevalence among drug injectors varies among different subpopulations. Sexually transmitted disease clinic attenders who are IV drug users show rates of 6.58% and 51.9% seropositivity. Incarcerated persons who are drug injectors were associated with seropositivity rates of 35% (adults) 60.9% (adolescents) 53.5% (adolescents in security institutes) and 18% (female inmates who volunteered for testing) with drug injection the most important risk factor in 90.4%. Among prostitute injectors rates were reported of 20% in 1988 and 50% in 1989-90 in the same population. Street children in Rio de Janeiro who use IV drugs (68 of 3389 surveyed) had a rate of 13.2% in 1987-88. The risk factors associated with HIV infection among drug injectors are socioeconomic status and injecting and sex practices. Co-infection patterns among drug injectors have also been found with concomitant HIV-1 and HTLV-1 reported in 20% of 85 HIV positive drug injectors. Overall these data suggest that there is an absolute increase in the number of AIDs cases among drug injectors rather than a decline in the proportion of cases reported in other transmission categories. Drug injector transmission poses a threat to the sex partners and offspring of injectors and provides a bridge to the heterosexual infection of women. While there is no obvious quick solution to the problem of IV drug use there are programs which can slow the spread of HIV among injectors. It is urgent to control sexual transmission and drug injection transmission of HIV in these countries.

Criteria for diagnosis of amyotrophic lateral sclerosis

Abstract: Os autores apresentam os casos de dois enfermos com diagnostico inicial de esclerose lateral amiotrofica e que, apos investigacao detalhada, tiveram-no afastado. Chamam a atencao para a necessidade de investigacao cuidadosa em todos os pacientes com suspeita clinica da doenca e propoem um protocolo para ser aplicado em todos os casos.

Paw preference in mice with callosal defects induced by prenatal gamma irradiation.

Abstract: The development of the corpus callosum of male Swiss mice was perturbed by exposure to gamma radiation at embryonic day 16 with total doses of 2 Gy (N = 48) or 3 Gy (N = 26). At adulthood paw preference was studied in these callosal defective animals and in 93 control nonirradiated male Swiss mice. The analysis of directional laterality indicated a populational tendency for right paw use in the 2 Gy group (60%) that was markedly increased in the 3 Gy group (95%). In the 3 Gy group, directional laterality was significantly different from chance in contrast to that observed in normal controls (49%). In the three groups most mice presented a significant individual paw preference. These data are consistent with our hypothesis that the early absence of the corpus callosum disrupts the normal pattern of directional asymmetries.

Street youth : social imbalance and health risks

Abstract: Street youth are children and adolescents who express, through their bodies and lives, misery and social abandonment. Paradoxically, they are also the embodiment of resistance and survival strategies in a very unfavourable environment. The current deterioration of citizens' rights and the social inequalities reflect the consequences of vicious cycles of economic and political crises in Brazil. Poverty conditions reach levels of misery and create strategies of survival that create multiple high-risk health situations. Many other factors make up the complex dynamics of these conflicts in which the limit of rejection and social abandonment are expressed in the violence of extermination. The proposals and solutions cannot be dissociated from the reality of this country and of the street youth lifestyle. Effective health education within this social context is difficult, but possible with the development of appropriate audio-visual material and the dissemination of preventive health information. A commitment to action must permeate all levels of decision making within the health system and in our society, for it is the essence of democracy and human rights.

An update of the stereology of the myocyte of the baboon's heart: analysis of the crista terminalis, interatrial and interventricular septa, and atrioventricular bundle

Abstract: We used light microscopy to compare the stereology of the myocytes from the following regions of the baboon's heart: a) cardiac walls (crista terminalis, interatrial and interventricular septa) and b) cardiac conduction tissue (atrioventricular bundle) Six hearts were perfused and several pieces of tissue were taken from these regions A staggered test lattice consisting of cycloids was superimposed on twelve random pairs of photomicrographs in order to make disectors, and on twelve other random fields for each cardiac region in order to estimate certain stereological parameters Statistically significant differences were found when comparing the number of myocytes from the crista terminalis (highest value) with either the interatrial or interventricular septum There is also a significant difference between the number of myocytes in the interventricular septum and the atrioventricular bundle (highest value) For the mean profile area of the myocytes, significant differences were found between the myocytes of both the crista terminalis and the interatrial septum, and those of the interventricular septum (highest value) Under the light microscope, myocytes from the two regions of the atrial wall studied were indistinguishable in size, since they constitute a single cell population It was also impossible to distinguish them from the atrioventricular cells The myocytes from the interventricular septum differed in both size and number from those of the right atrium, but only in number from those of the atrioventricular bundle

Brazilian population's aging: reflections and aspects to be considerei in the definition of research outlines for populational studies.

Abstract: Este artigo aborda questoes demograficas do envelhecimento, discute o processo de transicao demografica, as particularidades do Brasil em termos de suas diferencas regionais e mostra a importância de pesquisas que considerem estas diferencas tendo em vista sua importância nao so a nivel do pais mas tambem no interior das grandes metropoles brasileiras. Os autores defendem que os estudos epidemiologicos que tem a preocupacao de fornecer informacoes para o planejamento mais criterioso para a organizacao de servicos devem se preocupar com esses fatos. Neste artigo apresentam os resultados de uma pesquisa recentemente realizada no Rio de Janeiro que ao inves de trabalhar com a cidade como um todo selecionou, atraves de indicadores sociais, economicos e demograficos areas homogeneas e representativos de tres estratos da populacao. A partir dai pode-se identificar problemas especificos e demandas distintas. Recorte tambem foi feito por faixa etaria e sexo mostrando que a distribuicao de doencas e problemas dos idosos se dao de forma diferente. Enfase foi dado a mulher idosa e as atividades diarias do idoso.

Torsion and gauge-invariant massive electrodynamics

Abstract: We study electrodynamics in Einstein-Cartan space-time, that is, in space-time with torsion, and show an analogy with the Chern-Simons gauge-invariant massive electrodynamics. In our case, however, there is no arbitrary parameter, the torsionQ playing the role of the Chern-Simons parameterκ. This leads to bounds on the photon mass, charge, and torsion coupling.

Inhibition and induction of SOS responses in Escherichia coli by cobaltous chloride.

Abstract: Mutagenesis induced by several genotoxic agents has been reported to be inhibited by cobaltous chloride In order to study the effects of this metal in some SOS functions we evaluated mutagenesis, lysogenic induction and phage reactivation in Escherichia coli cells treated with CoCl2 We detected that cobaltous chloride, when present in the plating medium, was able to block mutagenesis and lysogenic induction promoted by UV irradiation We also found that CoCl2 blocked protein synthesis, so we propose that this effect can be responsible for the antimutagenic and antilysogenic effects of this metal On the other hand, if the cells were treated for a short period of time with CoCl2, in the absence of Mg, we observed that cobaltous chloride per se was able to promote lysogenic induction as well as to enhance the phage reactivation induced by UV irradiation We conclude that depending on experimental conditions, cobaltous chloride may act either as an inhibitor or as an inducer of the SOS functions

Direct bond brackets: cotton roll versus rubber dam isolation

Abstract: Forty-four brackets were bonded "in vivo" using cotton roll and rubber dam isolation. Maxillary and mandibular premolars, to be extracted for orthodontic reasons, were used in this study. After bonding, the teeth were retained in the mouth for at least 30 days. They were extracted using surgical elevators. After extraction, the teeth were secured in plastic rings using gypsum and kept in water for 7 days until debonding. A Universal Instron Machine was used to produce a shear force at a speed of 0.1 cm/min until each bracket was removed. No statistically significant differences for debonding strength were observed between the two types of isolation, nor between the buccal and palatal surfaces of the teeth. One hundred percent of the failures occurred at the bracket/composite interface.