Avaliação da função renal de cães sob dois protocolos para administração da cisplatina

OBJETIVO: Avaliar a função renal de cães sadios, sob dois protocolos para administração de cisplatina. MÉTODOS: Todos os animais foram submetidos a três sessões de quimioterapia com cisplatina (60mg/m², iv) a intervalos de 21 dias. Foi realizada fluidoterapia com solução de cloreto de sódio a 0,9%, (25mL/kg/hora,iv), durante duas horas e, após administração de cisplatina, por mais uma hora. Os animais do grupo 2 receberam furosemida (2mg/kg, iv) 20 minutos antes da administração da cisplatina. A avaliação da função renal foi feita por exame clinico, urinálise, concentrações séricas de uréia e creatinina, clearance de creatinina, excreção fracionada de sódio e de potássio e razão proteína: creatinina urinária. As avaliações foram feitas imediatamente antes e 1, 2, 5, e 21 dias após cada uma das três sessões de quimioterapia. RESULTADOS: Mantiveram-se dentro da normalidade, não sendo detectados sinais de lesões ou insuficiência renal. Os animais que não receberam furosemida sofreram aumento gradativo nas concentrações séricas de creatinina e diminuição no clearance da mesma. CONCLUSÃO: O regime de fluidoterapia empregado mostra ser efetivo em minimizar a ação nefrotóxica da cisplatina e benefício adicional importante é obtido pela administração de furosemida.

Respostas fisiológicas de estresse no matrinxã (Brycon amazonicus) após exercício físico intenso durante a captura

Para determinar as respostas de estresse do matrinxã após perseguição com puçá, juvenis (26,7±6,7 g) foram aclimatados em caixas plásticas e submetidos aos tratamentos: Controle (sem perseguição), Perseguição por 2 minutos, Perseguição por 5 minutos, Perseguição por 10 minutos (quatro repetições, N=8/tratamento). Amostras de sangue foram coletadas 15, 30 e 60 minutos após a perseguição para determinação do cortisol, glicose, sódio, cloreto, potássio, hematócrito, hemoglobina, número total de eritrócitos e osmolaridade. O perfil das respostas após o exercício físico dos peixes não mostrou as alterações típicas do estresse. Até 60 minutos após o estímulo, não ocorreram alterações nos níveis sanguíneos de cortisol, glicose e potássio nos peixes dos diferentes tratamentos. Os níveis de cloreto foram reduzidos 15 minutos após a natação forçada, enquanto os níveis do sódio mais baixos foram registrados 60 minutos depois. Houve redução da osmolaridade a partir dos 30 minutos após o estímulo, independente do tempo de perseguição. A natação forçada não interferiu nos indicadores hematológicos, corroborando os outros indicadores usados. Dessa forma, o exercício intenso dos peixes por até 10 minutos não foi estímulo suficiente para gerar respostas de estresse, sugerindo que o matrinxã é bastante resistente ao manejo de criação.

Avaliação e modelagem da absorção de H2S do gás natural em coluna de leito estagnado

Natural gas, although basically composed by light hydrocarbons, also presents contaminant gases in its composition, such as CO2 (carbon dioxide) and H2S (hydrogen sulfide). The H2S, which commonly occurs in oil and gas exploration and production activities, causes damages in oil and natural gas pipelines. Consequently, the removal of hydrogen sulfide gas will result in an important reduction in operating costs. Also, it is essential to consider the better quality of the oil to be processed in the refinery, thus resulting in benefits in economic, environmental and social areas. All this facts demonstrate the need for the development and improvement in hydrogen sulfide scavengers. Currently, the oil industry uses several processes for hydrogen sulfide removal from natural gas. However, these processes produce amine derivatives which can cause damage in distillation towers, can cause clogging of pipelines by formation of insoluble precipitates, and also produce residues with great environmental impact. Therefore, it is of great importance the obtaining of a stable system, in inorganic or organic reaction media, able to remove hydrogen sulfide without formation of by-products that can affect the quality and cost of natural gas processing, transport, and distribution steps. Seeking the study, evaluation and modeling of mass transfer and kinetics of hydrogen removal, in this study it was used an absorption column packed with Raschig rings, where the natural gas, with H2S as contaminant, passed through an aqueous solution of inorganic compounds as stagnant liquid, being this contaminant gas absorbed by the liquid phase. This absorption column was coupled with a H2S detection system, with interface with a computer. The data and the model equations were solved by the least squares method, modified by Levemberg-Marquardt. In this study, in addition to the water, it were used the following solutions: sodium hydroxide, potassium permanganate, ferric chloride, copper sulfate, zinc chloride, potassium chromate, and manganese sulfate, all at low concentrations (»10 ppm). These solutions were used looking for the evaluation of the interference between absorption physical and chemical parameters, or even to get a better mass transfer coefficient, as in mixing reactors and absorption columns operating in counterflow. In this context, the evaluation of H2S removal arises as a valuable procedure for the treatment of natural gas and destination of process by-products. The study of the obtained absorption curves makes possible to determine the mass transfer predominant stage in the involved processes, the mass transfer volumetric coefficients, and the equilibrium concentrations. It was also performed a kinetic study. The obtained results showed that the H2S removal kinetics is greater for NaOH. Considering that the study was performed at low concentrations of chemical reagents, it was possible to check the effect of secondary reactions in the other chemicals, especially in the case of KMnO4, which shows that your by-product, MnO2, acts in H2S absorption process. In addition, CuSO4 and FeCl3 also demonstrated to have good efficiency in H2S removal

Análise bromatológica de carnes antes e após o processamento para obtenção de charque

The process of salting and drying in the sun is used to preserve meat since the beginning of civilization. There is evidence that this preservation technique has arisen in Egypt, between 4,000 and 5,000 years ago. In our country, according to literature, was the first industrial product that gave the appearance of beef jerky, beef being produced, where about 70% to 75% of the muscle is composed of water, where it will be around 45% as a final product, according to the law in his article RIISPOA No. 432 provides that the jerky should contain no more than this amount of moisture in the muscular portion, or more than 15% of total ash with tolerance of up to 5% variation . Besides this parameter, proteins, lipids, ash, and minerals were analyzed in samples before and after the manufacturing process to know the content of these nutrients. Since these are considered important in product quality, thus the concentration in these samples, respectively, in the flesh Front (CD and CHD) before and after the manufacturing process for humidity were respectively 75.28% and 47.38% , the protein was 14.17 and 22.20 g / 100 g sample, 6.360 and 4.251 of lipids g/100g of the sample, and the ashes 0.974 9.144 g/100g sample, minerals like calcium and 4.074 30 , 06 ppm, sódio0, 055 and 5.401 g / L, sodium chloride, 0.139 and 13.74 g / L, potassium 237.5 and 166.8 ppm, 1.721 and 3.295 ppm iron, 0.143 and 0.135 ppm phosphorus, zinc and 4.690 6.905 ppm; magnésio14, 63 e13, 75 ppm manganese .017 e0, 007ppm, copper 0.057 and 0.039 ppm in the case of needle-type meat (CPA and CHPA), 68.04% and 44.17%, protein 13 , 72, and 24.42 g/100g of sample, 1.137 in the ash and 12.68 g / 100g of sample, and the minerals calcium 17.11 and 12.89 ppm; sódio0, 123 and 4.871 g / L, sodium chloride 0.312 and 12.39 g / L, potassium 305.3 and 182.1 ppm; ferro1, 817 and 1.513 ppm, 0.273 and 0.139 ppm phosphorus, zinc 6.305 and 4.783 ppm, 27.95 and 15.85 ppm magnesium, manganese and 0.025 0.011 ppm, 0.057 and 0.143 ppm copper and chromium 0.014 and 0.068 ppm

Eficácia da solução de cloreto de sódio a 7,5% com e sem dextran 70 a 6% na preservação da função renal de cães hipovolêmicos submetidos à isquemia-reperfusão

JUSTIFICATIVA E OBJETIVOS: As soluções hipertônicas de cloreto de sódio, associadas ou não a colóides hiperoncóticos, podem ser eficazes em proteger o rim em situações de hipovolemia. O objetivo deste estudo foi verificar, em cães, o real benefício dessas soluções sobre a função renal, em vigência de hipovolemia e isquemia do órgão. MÉTODO: em 24 cães, anestesiados com pentobarbital sódico, submetidos à nefrectomia direita e à expansão volêmica com solução de Ringer (1 ml.kg-1.min-1), foram observadas possíveis alterações renais morfo-funcionais após hemorragia de 20 ml.kg-1 e trinta minutos de total isquemia renal esquerda, com posterior reperfusão, além da repercussão renal da administração de soluções de cloreto de sódio 7,5% (SH) e esta em dextran 70 a 6% (SHD). Atributos estudados: FC, PAM, pressão de veia cava inferior, fluxo sangüíneo renal, resistência vascular renal, hematócrito, Na+, K+, osmolaridade plasmática, PaO2, PaCO2 e pH, depuração (para-aminohipurato de sódio - PAH-1, creatinina, osmolar, água livre, Na+, K+), fração de filtração, volume e osmolaridade urinários, excreções urinárias e fracionárias de Na+ e K+ e exame histopatológico do rim. Os atributos foram estudados em três grupos (G1, G2 e G3) e em cinco momentos. RESULTADOS: Houve elevação estatisticamente significativa da pressão arterial média em G2 e G3, da resistência vascular renal em G1, do fluxo sangüíneo renal e da depuração de PAH em G3, da excreção fracionária de Na+ em G2 e G3, das depurações de creatinina, osmolar, de água livre e de Na+ e K+, da excreção urinária de Na+ e K+ e do volume urinário em G3. CONCLUSÕES: A SHD administrada 15 minutos após hemorragia moderada e 30 minutos antes de insulto isquêmico de 30 minutos foi eficiente em proteger o rim de cães das repercussões da isquemia-reperfusão. Não foi constatada alteração histopatológica renal à microscopia óptica.

Hematological and biochemical profiles and histopathological evaluation of experimental intoxication by sodium fluoroacetate in cats

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Interaction between supraoptic nucleus and septal area in the control of water, sodium intake and arterial blood pressure induced by injection of angiotensin II

We investigated the effects of injection into the supraoptic nucleus (SON) of losartanand PD 123319 (nonpeptide AT(1) and AT(2)- angiotensin II [ANG II] receptor antagonists, respectively); d(CH2)(5)-Tyr(Me)-AVP (AVPA; an arginine-vasopressin [AVP] V-1 receptor antagonist), FK 409 (a nitric oxide [NO] donor), and N-W-mtro-(L)-arginine methyl ester ((L)-NAME; an NO synthase inhibitor) oil water intake, sodium chloride 3% (NaCl) intake and arterial blood pressure induced by injection of ANG 11 into the lateral septal area (LSA). Mate Holtzman rats (250-300 g) were implanted with cannulae into SON and LSA unilaterally. The drugs were injected in 0.5 mul over 30-60 s. Controls were injected with a similar volume of 0.15 M NaCl. ANG II was injected at a dose of 10 pmol. ANG II antagonists and AVPA were injected at doses of 80 nmol. FK 409 and (L)-NAME were injected at doses of 20 and 40 mug, respectively. Water and NaCl intake was measured over a 2-h period. Prior administration of losartan into the SON decreased water and NaCl intake induced by injection of ANG II. While there was a decrease in water intake, ANG II-induced NaCl intake was significantly increased following injection of AVPA. FK 409 injection decreased water intake and sodium intake induced by ANG II. L-NAME alone increased water and sodium intake and induced a pressor effect. (L)-NAME-potentiated water and sodium intake induced by ANG II. PD 123319 produced no changes in water or sodium intake induced by ANG II. The prior administration of losartan or AVPA decreased mean arterial pressure (MAP) induced by ANG II. PD 123319 decreased the pressor effect of ANG II to a lesser degree than losartan. FK 409 decreased the pressor effect of ANG II while (L)-NAME potentiated it. These results suggest that both ANG II AT, and AVP V, receptors and NO within the SON may be involved in water intake, NaCl intake and the pressor response were induced by activation of ANG II receptors within the LSA. These results do not support the involvement of LSA AT(2) receptors in the mediation of water and NaCl intake responses induced by ANG II, but influence the pressor response. (C) 2004 Elsevier B.V. All rights reserved.

Inhibitors of human collagenase, MMP1

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Fighting by sleep-deprived rats as a possible manifestation of panic: effects of sodium lactate

Increased fighting is an effect of desynchronized sleep deprivation (DSD) in rats, and recently this behavior has been suggested to be spontaneous panic and equivalent to panic disorder. In the present study we tested this hypothesis by evaluating the effect of sodium lactate on this aggressiveness, because this substance is recognized to induce spontaneous panic attacks in patients. A total of 186 male albino Wistar rats, 250-350 g, 90-120 days of age, were submitted to DSD (multiple platform method) for 0, 4, or 5 days. At the end of the deprivation period the rats were divided into subgroups respectively injected intraperitoneally with 1.86, 2.98 and 3.72 g/kg of 1 M sodium lactate, or 1.86 and 3.72 g/kg of 2 M sodium lactate. The control animals were submitted to the same procedures but received equivalent injections of sodium chloride. Regardless of DSD time, sleep-deprived animals that received sodium lactate presented a significantly higher mean number of fights (0.13 ± 0.02 fights/min) and a longer mean time spent in confrontation (2.43 ± 0.66 s/min) than the controls (0.01 ± 0.006 fights/min and 0.12 ± 0.07 s/min, respectively; P<0.01, Student t-test). For the sodium lactate group, concentration of the solution and time of deprivation increased the number of fights, with the mean number of fights and mean duration of fighting episodes being greater with the 2.98 g/kg dose using 1 M lactate concentration. These results support the hypothesis that fighting induced by DSD is probably a spontaneous panic manifestation. However, additional investigations are necessary in order to accept this as a promising animal model for studies on panic disorder.

Avaliação laboratorial do uso de solução salina hipertônica e isotônica e de furosemida no tratamento da intoxicação por amônia em bovinos

Para testar a eficiência de vários tratamentos de intoxicação por amônia em bovinos, foram utilizados 25 garrotes que receberam cloreto de amônio por infusão intravenosa (iv) até o surgimento de quadro convulsivo. em seguida, os animais foram alocados em um dos cinco grupos experimentais e tratados da seguinte forma: 1) controle: infusão (iv) de 300mL de solução salina isotônica (SSI), no decorrer de 4h; 2) infusão (iv) de 30mL kg-1 PV de SSI no decorrer de 4h e administração de 4L de água intraruminal por meio de sonda esofágica (ASE); 3) mesmo tratamento do grupo 2 e dose única (iv) de furosemida (2mg kg-1 PV) (F); 4) injeção (iv) de 5mL kg-1 PV de solução salina hipertônica (SSH) 7,2% nos primeiros 30min, seguida de 20mL kg-1 PV de SSI e 4L de ASE; 5) mesmo tratamento do grupo 4 e dose única de F. No decorrer de 4h após a convulsão, foram determinados os teores plasmáticos de amônia e glicose, ureia, creatinina, potássio e sódio séricos, volume e gravidade específica da urina, e excreção urinária de amônio e ureia. No momento da convulsão, os teores de amônia plasmáticos foram muito altos e idênticos em todos os tratamentos, mas no 120°min, nos grupos tratados com associação de SSH+SSI+ASE (grupos 4 e 5), houve diminuição desse metabólito. O uso de furosemida (grupos 3 e 5) não aumentou a excreção total de urina. A terapia com associação de SSH+SSI+ASE aumentou ainda o volume urinário e a excreção percentual urinária de ureia e amônia durante o período crítico da 1ª hora de tratamento, mas o uso de SSI+ASE (grupos 2 e 3) teve resultados intermediários. A eficiência do tratamento com SSH+SSI+ASE ou SSI+ASE foi superior ao grupo controle. Embora com efeito menor que o observado com SSH+SSI+ASE, a SSI+ASE promoveu melhora no quadro clínico geral e, ao término do experimento, promoveu também uma adequada desintoxicação da amônia.

Amniocentesis and biochemical evaluation of amniotic fluid in ewes at 70, 100 and 145 days of pregnancy

The objectives of this study were to determine the technical viability of amniocentesis in sheep and to observe biochemical changes in the amniotic fluid components. Amniotic fluid samples were collected by puncture in the greatest curvature of the uterine hum at days 70, 100, and 145 of pregnancy. The surgical procedure for collection of amniotic fluid samples was safe and efficient. For three stages of pregnancy, the following results were obtained: pH values 8.36, 7.34 and 7.37; glucose concentrations, 16.06. 8.58, and 3.79 g/dl; urea values, 42.68, 33.53, and 25.49 mg/dl; creatinine, 0.85, 5.04, and 11.25 g/dl; Gama-GT enzyme, 12.58, 14.20, and 12.30 UI/l; sodium concentrations, 146.60, 129.42, and 103.8 mmol/l: potassium concentrations, 9.79, 6.15, and 8.65 mmol/l; chloride, 96.59, 85.28, and 65.35 mmol/l; total protein, 0.14, 0.23, and 0.24 g/dl, respectively. (C) 2001 Elsevier B.V. B.V. All rights reserved.

Determination of interfacial co-ion concentration in ionic micelles by chemical trapping: Halide concentration at the interface of sodium dodecyl sulfate micelles

Products from the spontaneous reaction of a long-chain arenediazonium salt, 2,6-dimethyl-4-hexadecylbenzenediazonium tetrafluoroborate(16-ArN2BF4), in aqueous micellar solutions of sodium dodecyl sulfate (SDS)? are used to estimate the local concentration of chloride and bromide ions at the micellar surface. The arenediazonium ion, 16-ArN2+, which is totally bound to the SDS micelle, reacts by rate-determining loss of N-2 to give an aryl cation that traps available nucleophiles, i,e., H2O, Cl-, and Br-, to give stable phenol, 16-ArOH, and halobenzene products, 16-ArCl and 16-ArBr, respectively. Product yields, determined by HPLC, are related to local concentrations using calibration curves obtained from independent standards. The local concentrations determined by this method are consistent with co-ion concentrations calculated, using a cell model, by numerical integration of the Poisson-Boltzmann equation (PBE) taking into account salt-induced micellar growth. The salt dependence of the intel facial concentrations of Cl- and Br- are identical. indicating no specific interactions in the interfacial co-ion compartment. PBE calculations predict that, in micellar SDS, increasing the concentration of a particular halide salt (NaX) at constant concentration of another halide (NaY) should result in an increase in the local concentrations of both co-ions. Using this chemical-trapping method, this prediction was demonstrated experimentally.

Purification and biological activity of the thrombin-like substance isolated from Bothrops insularis venom

The venom of Bothrops insidaris snake, known in Brazil as jararaca ilhoa, contains a variety of proteolytic enzymes such as a thrombin-like substance that is responsible for various pharmacological effects. B. insularis venom chromatography profile showed an elution of seven main fractions. The thrombin-like activity was detected in fractions I and 111, the latter being subjected to two other chromatographic procedures, so to say DEAE and Hi Trap Benzamidine. The purity degree of this fraction was confirmed by analytical reverse phase HPLC, which displayed only one main fraction confirmed by SDS-PAGE constituting fraction III. About 5 mu g of fraction III protein potentiated the secretion of insulin induced by 2.8mM of glucose in rats isolated pancreatic beta-cells treated; the increase being around 3-fold higher than its respective control. B. insidaris lectin (BiLec; 10 mu g/mL) was also studied as to its effect on the renal function of isolated perfused rat kidneys with the use of six Wistar rats. BiLec increased perfusion pressure (PP), renal vascular resistence (RVR), urinary flow (UF) and glomerular filtration rate (GFR). Sodium (%TNa+) and chloride tubular reabsorption (%TCl-) decreased at 120 min, without alteration in potassium transport. In conclusion, the thrombin-like substance isolated from B. insularis venom induced an increase in insulin secretion, in vitro, and transiently altered vascular, glomerular and tubular parameters in the isolated rat kidney. (c) 2006 Elsevier Ltd. All rights reserved.

Bombesin affects the central nervous system to produce sodium intake inhibition in rats

Bombesin (BN) elicits in the rat important behavioural modifications, including inhibition of food and of water intake. Recently, it has been observed that the peptide also inhibits the intake of sodium chloride. To stare whether BN possesses a selective antinatriorexic effect or it elicits only an aspecific depression of ingestive behaviour, we studied the effects of this peptide on the intake of sodium, water or sucrose of Wistar rats after injections into the fourth brain ventricle or into selected brain areas involved in the control of sodium intake, containing BN-like peptides and/or their precursors or specific receptors. We observed that: a) BN (100-200 ng/rat) injected into the fourth brain ventricle inhibits not only the intake of 2% NaCl of sodium depleted rats but also that of water and of 5% sucrose; b) BN (5-50 ng/rat) administered into the nucleus of the solitary tract and the medial amygdala does not influence the intake of these fluids and c) BN (5-50 ng/rat) injected into the paraventricular nucleus does not influence the intake of water and 5% sucrose but potently inhibits that of 2% NaCl. We concluded that the inhibitory effect elicited on salt intake by intracranial administration of BN is selective for this behaviour and is not the expression of an aspecific depression of ingestive behaviour. (C) 1998 Elsevier B.V.

Preparation of zinc sodium polyphosphates glasses from coacervates precursors. Characterisation of the obtained glasses, and their applications

A soft chemistry route is described to obtain glasses in the P2O5-Na2O-ZnO-H2O. It is based on the addition of zinc salts to coacervates prepared from sodium polyphosphate. The processing of these coacervates leads to polyphosphate glasses with the same properties as those of glasses prepared in the classical way. So far, little work has been implemented in this system using 'coacervate route'. However, it makes an attractive method for coating and joining processes on the industrial scale. As the anion associated to zinc may take part in the adhesion mechanism, coacervate formation has been studied using zinc chloride, nitrate and sulphate as starting materials. The physical properties of the glasses obtained by this method are reported and potential applications of zinc and silver coacervate are described. (C) 2002 Academie des sciences / Editions scientifiques et medicales Elsevier SAS.