Gota suspensa para avaliação de aldeído total no ar interno e externo do ambiente

A sensitive and simple system was proposed for the in situ measurement of total aldehyde in outdoor or indoor ambient. The method is based on the use of a reagent drop as an useful interface to preconcentrate the sample prior to determination of total aldehyde as formaldehyde. The drop is formed at the tip of a cylindrical tube that contains two optical fibers placed on opposite sides and in contact with the reagent solution. One optical fiber carries the red light to the drop form a light emitting diode (LED). The transmitted light is measured by a second optical fiber/photodiode system. The analytical signal is read and converted into absorbance. The reagent solution of 3-methyl-2-benzothiazoline hydrazone (MBTH) forms a blue cation during reaction with formaldehyde that can be measured at 660 nm. Some aspects of kinetics reaction formation of dye were reevaluated. The formaldehyde reacts with MBTH and forms the azine in about 12 min. The oxidation of MBTH by Fe (III) and the formation of dye requires 3 min. The absorbance of the reagent drop is proportional to the sampling time and to the analyte concentration. The absorbance signal increases with increased sample gas flow until a maximum is reached then decreases until it forms a plateau. The proposed method was evaluated using both outdoor and indoor samples, and it was shown to viable provide an accurate measure of total aldehyde.

Determinação da composição isotópica de estrôncio em águas naturais: exemplos de sua aplicação em águas subsuperficiais da zona costeira na região Bragantina-PA

Analytical procedures used for determining the concentrations and isotope composition of strontium in subsurface waters, by mass spectrometry, are described. Sampling was performed in coastal plateaus, salt marsh and mangrove environments in the coastal region of Pará. Coastal plateau waters have delta87Sr between 1.51 and 6.26‰ and Sr concentration bellow 58 ppb. Salt marsh waters show delta87Sr between 0.55 and 0.90‰ and Sr concentration between 93 and 114 ppm, while mangrove waters have delta87Sr‰ around zero and Sr concentration above 15 ppm. Differences in the 87Sr/86Sr ratio in these subsurface waters are detected, as well as seasonal variations in the coastal pleteau waters.

Resultados científicos do cruzeiro do "Baependi" e do "Vega" à Ilha da Trindade: contribuição para o conhecimento da plataforma insular da Ilha da Trindade

The oceanographic work realized during 10 days in the surroundings of the eruptive island of Trindade, 20º30'36" lat. S - 29º19'26" long. W, had as principal aim the determination of the insular plateau, whose knowledge was very insufficient. Thus were established some oceanographic stations and sounding lines were realized by means of an echobathymeter whose responses were initially verified with mechanical soundings obtaneid by means of a Thomson sounder. The insular plateau is very narrow and exhibits a sudden fall between the 100 and 120 m. depth line at 740 m. - 2950 m. from the coast. Its greatest depth is of 108,30 m. and its mean inclination is of 8,12%. The plateau of the island of Trindade is separated from that of the neighbouring group of Martim Yaz by great depths. The bottoms are rocky near the coast, the blocks having been produced by the rupture of the magmatic mass of the island. Further away from the coast, the size of the rocks gradually diminishes up to the fine sand thickness. In the litoral zone there are abundant tufts of living Lithothamnion with a rich associated flora and fauna, which partly covers the rocks themselves. Further off at sea, the spheres of the dead alga with its commensals are cimented together by sedimentation. The spheres are further broken up and become an integrating part of the sand. The results of the physical and chemical analyses of the sand bottoms are shown in tables 2 and 3. The coast is either of abrupt rocky walls falling down to sea level, or of shores, made of pebbles or of sand. Anyhow, there are frequently Lithothamnion terraces slightly inclinated towards the bottom (chemical analysis table 1).

Evolução e implementação dos planos de manejo em parques nacionais no estado do Rio de Janeiro

O plano de manejo é um documento técnico mediante o qual se estabelece o zoneamento e as normas que devem presidir o uso da área de uma unidade de conservação e o manejo dos recursos naturais, inclusive a implantação das estruturas físicas necessárias à gestão. Eles foram legalmente instituídos no Brasil em 1979 com o objetivo de adequar e orientar o manejo ecológico dos parques nacionais, até então em sua maioria criados apenas no papel, apontando a necessidade de realizar o zoneamento como base do ordenamento e gestão do território protegido. Contudo, o processo de elaboração e implementação desse documento foi extremamente variado e sofreu uma série de modificações ao longo do tempo visando seu aperfeiçoamento. O objetivo deste trabalho foi analisar a evolução do plano de manejo no contexto da gestão dos parques nacionais no país analisando como caso concreto a sua implementação no estado do Rio de Janeiro. A elaboração de planos de manejo para parques no Brasil foi marcada pela existência de três referências metodológicas distintas o que se refletiu na variedade de planos identificados para os cinco parques nacionais analisados neste trabalho (PARNAs do Itatiaia, da Serra dos Órgãos, da Tijuca, da Serra da Bocaina e da Restinga da Jurubatiba). Como padrão geral os planos de manejo não foram elaborados, nem revisados dentro dos prazos e periodicidade estabelecida pela legislação, o que denota uma dificuldade na implementação desse instrumento mesmo quase trinta anos após a sua instituição.

SOIL ORGANIC CARBON, CARBON STOCK AND THEIR RELATIONSHIPS TO PHYSICAL ATTRIBUTES UNDER FOREST SOILS IN CENTRAL AMAZONIA

ABSTRACT The soil carbon under Amazonian forests has an important roles in global changing, making information on the soil content and depths of these stocks are considerable interest in efforts to quantify soil carbon emissions to the atmosphere.This study quantified the content and soil organic carbon stock under primary forest up to 2 m depth, at different topographic positions, at Cuieiras Biological Reserve, Manaus/ ZF2, km 34, in the Central Amazon, evaluating the soil attributes that may influence the permanence of soil carbon. Soil samples were collected along a transect of 850 m on topographic gradient Oxisol (plateau), Ultisol (slope) and Spodosol (valley). The stocks of soil carbon were obtained by multiplying the carbon content, soil bulk density and trickiness of soil layers. The watershed was delimited by using STRM and IKONOS images and the carbon contend obtained in the transects was extrapolated as a way to evaluate the potential for carbon stocks in an area of 2678.68 ha. The total SOC was greater in Oxisol followed by Spodosol and Ultisol. It was found direct correlations between the SOC and soil physical attributes. Among the clay soils (Oxisol and Ultisol), the largest stocks of carbon were observed in Oxisol at both the transect (90 to 175.5 Mg C ha-1) as the level of watershed (100.2 to 195.2 Mg C ha-1). The carbon stocks under sandy soil (Spodosol) was greater to clay soils along the transect (160-241 Mg C ha-1) and near them in the Watershed (96.90 to 146.01 Mg C ha-1).

Emprego da submucosa intestinal suína em uretroplastias complexas

We report the use of Porcine Intestinal Submucosa (PIS) in association with Johanson technique for urethroplasty, in the treatment of recurring urethral stenosis. The patient had obliterans xerotica balanitis and had previously undergone 15 internal uretotomies as well as various unsuccessful urethral dilations. As a result of stenotic extension, another surgery was planned using Johanson technique. During the first part of the surgery, intense local fibrosis was observed, which required greater care and protection to avoid fistulae formation. PIS was interposed to reduce the chances of the occurrence of this dreaded complication. During the second part of the surgery, a skin flap obtained from tissue parallel to the urethral plateau was used to prepare a neourethra according to the norms of this technique. PIS was fixed at its extremities, and interposed between the neourethral suture and the skin suture to prevent any contact between them. The procedure was completed with the use of meatoplasty and glandulaplasty. After 6-month follow up, clinical and urodynamic improvement could be seen. If these results can be confirmed by more extensive studies, PIS will provide new perspectives for complex urethroplasties.

Experimental osteoarthritis in rabbits: lesion progression

The aim of this study was to evaluate the progression of lesions in different stages of osteoarthritis (OA) experimental by radiography (RX), computed tomography (CT), macroscopic and histopathology, linking these different diagnostic methods, helped to provide information that helps the best time for the therapeutic approach. Four experimental periods were delineated at 3, 6, 9 and 12 weeks after induction of OA, known as PI, PII, PIII and PIV, respectively, each with six animals. We evaluated the five compartments of the femorotibial joint: medial femoral condyle (MFC), lateral femoral condyle (LFC), medial tibial plateau (MTP), lateral tibial plateau (LTP) and femoral trochlea (FT). Therefore we established an index by compartment (IC) and by adding such an index was estimated joint femorotibial (IFT). It was observed that the CFM was the compartment with the highest IC also differed significantly (p<0.05) from other compartments. Compartments showed no significant difference (p>0.05) between the PI and PII, however contrary fact occurred between the PII and PIII (p<0.05), PIII and PIV (p<0.01) and between PI and PIV (p<0.001). Similarly the IFT, showed a significant difference in the animals of PIV compared to PI (p<0.001), PII (p<0.001) and PIII (p<0.01), and there was no statistical difference (p> 0.05) between the PI and PII. In the variation of the average interval between periods, there was a higher value between the PIII PIV and for the other intervals of time periods (PI, PII, and PIII-PII). However, these intervals showed no statistically significant difference (p>0.05). Through the RX, CT, macroscopic and histopathological findings, we found similar patterns among individuals within the same period demonstrating a gradual progression of the disease. These results show that between 3 and 6 weeks progression of the lesion is slower and probably also can be reversed in comparison to other ranges where proved further progression between 9 and 12 weeks after induction of trauma OA. These results may provide a better therapeutic approach aimed at reversing the lesions in early stages of OA. We conclude that the interconnection of the four diagnostic methods individually classified into scores, which were unified in both indices in the evaluation by the femorotibial joint compartment and may represent a diagnostic condition closer to the true condition of the injury and its progression.

Frequency of Equine Monocytic Ehrlichiosis (EME) in Brazil

From a cross-sectional observational study with convenience samples, 347 blood samples from horses were collected from different physiographic regions, as follows: Santa Catarina Plateau (Santa Catarina State - SC), Médio Paraíba do Sul (São Paulo State - SP and Rio de Janeiro State RJ), Mountainous and Metropolitan regions (Rio de Janeiro State - RJ). Samples were tested for the presence of antibodies (IgG) anti Neorickettsia risticii by indirect immunofluorescence assay (IFA). The frequency obtained in this study corroborates with the ones obtained in the U.S.A., which refers to endemic regions. Fisher's exact test showed significant differences in the number of positive animals between regions, indicating that the probability of an animal becoming infected varies depending on the area. The CI 95% revealed no association between infection and geopolitical space. Moreover, Odds ratio test showed differences of an animal getting infected in different regions. This event could be influenced by the type of treatment used in each area, as the seasonal frequency of injury or even potential vectors. Therefore, there are seropositive animals for N. risticii in the studied areas, suggesting that this agent may be circulating in those regions. Future studies mainly based on molecular analyzes are needed to confirm these serological findings.

Histochemical study of the oviducal gland and analysis of the sperm storage tubules of Mustelus schmitti Springer, 1939 (Chondrichthyes, Triakidae)

Abstract: The paired oviducal glands of immature and mature females of Mustelus schmitti were examined macro and microscopically. Findings indicate that these glands possessed the same zonation as in most chondrichthyans from anterior to posterior: club, papillary, baffle and terminal zones. The whole gland is composed by simple tubular glands that connect with transverse grooves all along the organ. The club zone presents a typical indian club shape with a simple columnar and ciliated epithelium including secretory cells PAS (+) and AB (+). The papillary zone is characterized by lamella forming small and long cones in numbers of three. The epithelium of this zone contains ciliated cells with apical nuclei and secretory cells with basal nuclei that stain AB (+)The baffle zone consists of apically flattened lamellae alternating with spinnerets which are small projections disposed by both sides of the plateau. This whole structure is present in number of 8 or 9 units. A simple columnar ciliated epithelium covers the plateau and spinnerets and no AB or PAS staining is observed. The epithelium of the terminal zone is PAS (-) and AB (+), and elongated tubules, that run adjacent to the baffle zone are the site where groups of spermatozoa are clearly observed in the lumen. The epithelium of the sperm storage tubules do not stain with any of the dyes tested. Sperm was also observed in the baffle zone, presumably in its way to the fecundation in the oviduct because it displays no aggregation pattern and was between the folds of the epithelium. By scanning electron microscopy sperm was observed in the club and baffle zones in a gland which belonged to a pregnant female.

Monosodium glutamate (MSG)-obese rats develop glucose intolerance and insulin resistance to peripheral glucose uptake

Different levels of insulin sensitivity have been described in several animal models of obesity as well as in humans. Monosodium glutamate (MSG)-obese mice were considered not to be insulin resistant from data obtained in oral glucose tolerance tests. To reevaluate insulin resistance by the intravenous glucose tolerance test (IVGTT) and by the clamp technique, newborn male Wistar rats (N = 20) were injected 5 times, every other day, with 4 g/kg MSG (N = 10) or saline (control; N = 10) during the first 10 days of age. At 3 months, the IVGTT was performed by injecting glucose (0.75 g/kg) through the jugular vein into freely moving rats. During euglycemic clamping plasma insulin levels were increased by infusing 3 mU . kg-1 . min-1 of regular insulin until a steady-state plateau was achieved. The basal blood glucose concentration did not differ between the two experimental groups. After the glucose load, increased values of glycemia (P<0.001) in MSG-obese rats occurred at minute 4 and from minute 16 to minute 32. These results indicate impaired glucose tolerance. Basal plasma insulin levels were 39.9 ± 4 µU/ml in control and 66.4 ± 5.3 µU/ml in MSG-obese rats. The mean post-glucose area increase of insulin was 111% higher in MSG-obese than in control rats. When insulinemia was clamped at 102 or 133 µU/ml in control and MSG rats, respectively, the corresponding glucose infusion rate necessary to maintain euglycemia was 17.3 ± 0.8 mg . kg-1 . min-1 for control rats while 2.1 ± 0.3 mg . kg-1 . min-1 was sufficient for MSG-obese rats. The 2-h integrated area for total glucose metabolized, in mg . min . dl-1, was 13.7 ± 2.3 vs 3.3 ± 0.5 for control and MSG rats, respectively. These data demonstrate that MSG-obese rats develop insulin resistance to peripheral glucose uptake

Ca2+ dependence of gluconeogenesis stimulation by glucagon at different cytosolic NAD+-NADH redox potentials

The influence of Ca2+ on hepatic gluconeogenesis was measured in the isolated perfused rat liver at different cytosolic NAD+-NADH potentials. Lactate and pyruvate were the gluconeogenic substrates and the cytosolic NAD+-NADH potentials were changed by varying the lactate to pyruvate ratios from 0.01 to 100. The following results were obtained: a) gluconeogenesis from lactate plus pyruvate was not affected by Ca2+-free perfusion (no Ca2+ in the perfusion fluid combined with previous depletion of the intracellular pools); gluconeogenesis was also poorly dependent on the lactate to pyruvate ratios in the range of 0.1 to 100; only for a ratio equal to 0.01 was a significantly smaller gluconeogenic activity observed in comparison to the other ratios. b) In the presence of Ca2+, the increase in oxygen uptake caused by the infusion of lactate plus pyruvate at a ratio equal to 10 was the most pronounced one; in Ca2+-free perfusion the increase in oxygen uptake caused by lactate plus pyruvate infusion tended to be higher for all lactate to pyruvate ratios; the most pronounced difference was observed for a lactate/pyruvate ratio equal to 1. c) In the presence of Ca2+ the effects of glucagon on gluconeogenesis showed a positive correlation with the lactate to pyruvate ratios; for a ratio equal to 0.01 no stimulation occurred, but in the 0.1 to 100 range stimulation increased progressively, producing a clear parabolic dependence between the effects of glucagon and the lactate to pyruvate ratio. d) In the absence of Ca2+ the relationship between the changes caused by glucagon in gluconeogenesis and the lactate to pyruvate ratio was substantially changed; the dependence curve was no longer parabolic but sigmoidal in shape with a plateau beginning at a lactate/pyruvate ratio equal to 1; there was inhibition at the lactate to pyruvate ratios of 0.01 and 0.1 and a constant stimulation starting with a ratio equal to 1; for the lactate to pyruvate ratios of 10 and 100, stimulation caused by glucagon was much smaller than that found when Ca2+ was present. e) The effects of glucagon on oxygen uptake in the presence of Ca2+ showed a parabolic relationship with the lactate to pyruvate ratios which was closely similar to that found in the case of gluconeogenesis; the only difference was that inhibition rather than stimulation of oxygen uptake was observed for a lactate to pyruvate ratio equal to 0.01; progressive stimulation was observed in the 0.1 to 100 range. f) In the absence of Ca2+ the effects of glucagon on oxygen uptake were different; the dependence curve was sigmoidal at the onset, with a well-defined maximum at a lactate to pyruvate ratio equal to 1; this maximum was followed by a steady decline at higher ratios; at the ratios of 0.01 and 0.1 inhibition took place; oxygen uptake stimulation caused by glucagon was generally lower in the absence of Ca2+ except when the lactate to pyruvate ratio was equal to 1. The results of the present study demonstrate that stimulation of gluconeogenesis by glucagon depends on Ca2+. However, Ca2+ is only effective in helping gluconeogenesis stimulation by glucagon at highly negative redox potentials of the cytosolic NAD+-NADH system. The triple interdependence of glucagon-Ca2+-NAD+-NADH redox potential reveals highly complex interrelations that can only be partially understood at the present stage of knowledge

Validation of transit-time flowmetry for chronic measurements of regional blood flow in resting and exercising rats

The objective of the present study was to validate the transit-time technique for long-term measurements of iliac and renal blood flow in rats. Flow measured with ultrasonic probes was confirmed ex vivo using excised arteries perfused at varying flow rates. An implanted 1-mm probe reproduced with accuracy different patterns of flow relative to pressure in freely moving rats and accurately quantitated the resting iliac flow value (on average 10.43 ± 0.99 ml/min or 2.78 ± 0.3 ml min-1 100 g body weight-1). The measurements were stable over an experimental period of one week but were affected by probe size (resting flows were underestimated by 57% with a 2-mm probe when compared with a 1-mm probe) and by anesthesia (in the same rats, iliac flow was reduced by 50-60% when compared to the conscious state). Instantaneous changes of iliac and renal flow during exercise and recovery were accurately measured by the transit-time technique. Iliac flow increased instantaneously at the beginning of mild exercise (from 12.03 ± 1.06 to 25.55 ± 3.89 ml/min at 15 s) and showed a smaller increase when exercise intensity increased further, reaching a plateau of 38.43 ± 1.92 ml/min at the 4th min of moderate exercise intensity. In contrast, exercise-induced reduction of renal flow was smaller and slower, with 18% and 25% decreases at mild and moderate exercise intensities. Our data indicate that transit-time flowmetry is a reliable method for long-term and continuous measurements of regional blood flow at rest and can be used to quantitate the dynamic flow changes that characterize exercise and recovery

Effect of pilocarpine mouthwash on salivary flow

Pilocarpine is a cholinergic agonist that increases salivary flow and has been used to treat xerostomia. Oral intake is the most frequent route of administration. Adverse effects are dose-dependent and include sudoresis, facial blushing and increased urinary frequency. The objective of the present study was to evaluate the effects of topical pilocarpine solutions as mouthwashes on salivary flow and their adverse effects on healthy subjects. Forty volunteers received 10 ml 0.5, 1 and 2% pilocarpine solutions or 0.9% saline in a randomized, double-blind, placebo-controlled manner. Salivation was measured before and 45, 60 and 75 min after mouth rinsing for 1 min with 10 ml of saline or pilocarpine solutions. Vital signs were measured and ocular, gastrointestinal and cardiovascular symptoms, anxiety and flushing were estimated using visual analog scales. There was a dose-dependent increase in salivation. Salivation measured after 1 and 2% pilocarpine (1.4 ± 0.36 and 2.22 ± 0.42 g, respectively) was significantly (P<0.001) higher than before (0.70 ± 0.15 and 0.64 ± 0.1 g), with a plateau between 45 and 75 min. Cardiovascular, visual, gastrointestinal and behavioral symptoms and signs were not changed by topical pilocarpine. Mouth rinsing with pilocarpine solutions at concentrations of 1 to 2% induced a significant objective and subjective dose-dependent increase in salivary flow, similar to the results reported by others studying the effect of oral 5 mg pilocarpine. The present study revealed the efficacy of pilocarpine mouthwash solutions in increasing salivary flow in healthy volunteers, with no adverse effects. Additional studies on patients with xerostomia are needed.

Effect of acute nitric oxide synthase inhibition in the modulation of heart rate in rats

Acute nitric oxide synthase inhibition with N G-nitro-L-arginine methyl ester (L-NAME) on chronotropic and pressor responses was studied in anesthetized intact rats and rats submitted to partial and complete autonomic blockade. Blood pressure and heart rate were monitored intra-arterially. Intravenous L-NAME injection (7.5 mg/kg) elicited the same hypertensive response in intact rats and in rats with partial (ganglionic and parasympathetic blockade) and complete autonomic blockade (38 ± 3, 55 ± 6, 54 ± 5, 45 ± 5 mmHg, respectively; N = 9, P = NS). L-NAME-induced bradycardia at the time when blood pressure reached the peak plateau was similar in intact rats and in rats with partial autonomic blockade (43 ± 8, 38 ± 5, 46 ± 6 bpm, respectively; N = 9, P = NS). Rats with combined autonomic blockade showed a tachycardic response to L-NAME (10 ± 3 bpm, P<0.05 vs intact animals, N = 9). Increasing doses of L-NAME (5.0, 7.5 and 10 mg/kg, N = 9) caused a similar increase in blood pressure (45 ± 5, 38 ± 3, 44 ± 9 mmHg, respectively; P = NS) and heart rate (31 ± 4, 34 ± 3, 35 ± 4 bpm, respectively; P = NS). Addition of L-NAME (500 µM) to isolated atria from rats killed by cervical dislocation and rats previously subjected to complete autonomic blockade did not affect spontaneous beating or contractile strength (N = 9). In vivo results showed that L-NAME promoted a tachycardic response in rats with complete autonomic blockade, whereas the in vitro experiments showed no effect on intrinsic heart rate, suggesting that humoral mechanisms may be involved in the L-NAME-induced cardiac response.

High doses of riboflavin and the elimination of dietary red meat promote the recovery of some motor functions in Parkinson's disease patients

Abnormal riboflavin status in the absence of a dietary deficiency was detected in 31 consecutive outpatients with Parkinson's disease (PD), while the classical determinants of homocysteine levels (B6, folic acid, and B12) were usually within normal limits. In contrast, only 3 of 10 consecutive outpatients with dementia without previous stroke had abnormal riboflavin status. The data for 12 patients who did not complete 6 months of therapy or did not comply with the proposed treatment paradigm were excluded from analysis. Nineteen PD patients (8 males and 11 females, mean age ± SD = 66.2 ± 8.6 years; 3, 3, 2, 5, and 6 patients in Hoehn and Yahr stages I to V) received riboflavin orally (30 mg every 8 h) plus their usual symptomatic medications and all red meat was eliminated from their diet. After 1 month the riboflavin status of the patients was normalized from 106.4 ± 34.9 to 179.2 ± 23 ng/ml (N = 9). Motor capacity was measured by a modification of the scoring system of Hoehn and Yahr, which reports motor capacity as percent. All 19 patients who completed 6 months of treatment showed improved motor capacity during the first three months and most reached a plateau while 5/19 continued to improve in the 3- to 6-month interval. Their average motor capacity increased from 44 to 71% after 6 months, increasing significantly every month compared with their own pretreatment status (P < 0.001, Wilcoxon signed rank test). Discontinuation of riboflavin for several days did not impair motor capacity and yellowish urine was the only side effect observed. The data show that the proposed treatment improves the clinical condition of PD patients. Riboflavin-sensitive mechanisms involved in PD may include glutathione depletion, cumulative mitochondrial DNA mutations, disturbed mitochondrial protein complexes, and abnormal iron metabolism. More studies are required to identify the mechanisms involved.