O papel dos rins no equilíbrio ácido-básico em cães submetidos aos efeitos do halotano e hipercapnia

In eighteen dogs, the effects of halothane (0,75% and 1,5%) associated with a normo and hypercapnia (PaCO2 from 30 to 80 mmHg) on acid-base balance were studied. Determinations of creatine clearance, urinary flow, urinary acid excretion, and urinary ammonium excretion were made. Based on the results, it is concluded that halothane associated with hypercapnia decreases the glomerular filtration rate, the urinary flow, the urinary pH and the urinary bicarbonate and sodium excretion, increases the plasmatic bicarbonate concentration, the bicarbonate reabsorbed, the urinary acid excretion and the urinary ammonium excretion, but does not alter the base excess.

Free diet selection by broilers as influenced by dietary macronutrient ratio and corticosterone supplementation. 1. Diet selection, organ weights, and plasma metabolites

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Independent impact of glycemia ad blood pressure in albuminuria on high-risk subjects for metabolic syndrome

Background: Microalbuminuria may reflect diffuse endothelial damage. Considering that diabetes and hypertension cause vasculopathy, we investigated associations of albumin-to-creatinine ratio (ACR) with plasma glucose and blood pressure levels in high-risk subjects for metabolic syndrome. Methods: A sample of 519 (246 men) Japanese-Brazilians (aged 60 ± 11 years), who participated in a population-based study, had their ACR determined in a morning urine specimen. Backward models of multiple linear regression were created for each gender including log-transformed values of ACR as dependent variable; an interaction term between diabetes and hypertension was included. Results: Macroalbuminuria was found in 18 subjects. ACR mean values for subjects with normal glucose tolerance, impaired fasting glycemia, impaired glucose tolerance and diabetes were 9.9 ± 6.0, 19.0 ± 35.4, 20.7 ± 35.4, and 33.9 ± 55.0 mg/g, respectively. Diabetic subjects showed higher ACR than the others (p < 0.05). An increase in the proportion of albuminuric subjects was observed as glucose metabolism deteriorated (4.9, 17.0, 23.0 and 36.0%). Stratifying into 4 groups according to postchallenge glycemia (< 7.8 mmol/l, n = 9 1; ≥ 7.8 mmol/l, n = 4 10) and hypertension, hypertensive and glucose-intolerant subgroups showed higher ACR values. ACR was associated with gender, waist circumference, blood pressure, plasma glucose and triglyceride (p < 0.05); albuminuric subjects had significantly higher levels of such variables than the normoalbuminuric ones. In the final models of linear regression, systolic blood pressure and 2-hour glycemia were shown to be independent predictors of ACR for both genders (p < 0.05). In men, also waist was independently associated with ACR. No interaction was detected between diabetes and hypertension. Conclusions: These findings suggest that both glucose intolerance and hypertension could have independent but not synergistic effects on endothelial function - reflected by albumin loss in urine. Such hypothesis needs to be confirmed in prospective studies. © 2004 Dustri-Verlag Dr. K. Feistle.

Evaluation of toxicity after one-months treatment with Bauhinia forficata decoction in streptozotocin-induced diabetic rats

Background: Previous experiments have shown that a decoction of Bauhinia forficata leaves reduces the changes in carbohydrate and protein metabolism that occur in rats with streptozotocin-induced diabetes. In the present investigation, the serum activities of enzymes known to be reliable toxicity markers were monitored in normal and streptozotocin-diabetic rats to discover whether the use of B. forficata decoction has toxic effects on liver, muscle or pancreas tissue or on renal microcirculation. Methods: An experimental group of normal and streptozotocin-diabetic rats received an aqueous decoction of fresh B. forficata leaves (150 g/L) by mouth for 33 days while a control group of normal and diabetic rats received water for the same length of time. The serum activity of the toxicity markers lactate dehydrogenase, creatine kinase, amylase, angiotensin-converting enzyme and bilirubin were assayed before receiving B. forficata decoction and on day 19 and 33 of treatment. Results: The toxicity markers in normal and diabetic rats were not altered by the diabetes itself nor by treatment with decoction. Whether or not they received B. forficata decoction the normal rats showed a significant increase in serum amylase activity during the experimental period while there was a tendency for the diabetic rats, both treated and untreated with decoction, to have lower serum amylase activities than the normal rats. Conclusions: Administration of an aqueous decoction of B. forficata is a potential treatment for diabetes and does not produce toxic effects measurable with the enzyme markers used in our study. © 2004 Pepato et al; licensee BioMed Central Ltd.

Biochemical and hematological study of goats envenomed with natural and 60Co-irradiated bothropic venom

Venoms from snakes of the Bothrops genus are proteolytic, coagulant, hemorrhagic and nephrotoxic, causing edema, necrosis, hemorrhage and intense pain at the bite site, besides systemic alterations. Many adjuvants have been added to the venom used in the sensitization of antiserum-producer animals to increase antigenic induction and reduce the envenomation pathological effects. Gamma radiation from 60Co has been used as an attenuating agent of the venoms toxic properties. The main objective was to study, comparatively, clinical and laboratory aspects of goats inoculated with bothropic (Bothrops jararaca) venom, natural and irradiated from a 60Co source. Twelve goats were divided into two groups of six animals: GINV, inoculated with 0.5mg/kg of natural venom; and GIIV, inoculated with 0.5mg/kg of irradiated venom. Blood samples were collected immediately before and one, two, seven, and thirty days after venom injection. Local lesions were daily evaluated. The following exams were carried out: blood tests; biochemical tests of urea, creatinine, creatine kinase (CK), aspartate amino-transferase (AST) and alanine amino-transferase (ALT); clotting time; platelets count; and total serum immunoglobulin measurement. In the conditions of the present experiment, irradiated venom was less aggressive and more immunogenic than natural venom.

Atividades séricas da aspartato aminotransferase, creatina quinase e lactato desidrogenase de eqüinos submetidos ao teste padrão de exercício progressive em esteira

The aim of this study was to determine the serum activities of enzymes aspartate aminotransferase, creatine kinase and lactate dehydrogenase in Arabian horses submitted to exercise on high-speed equine treadmill. Eleven mature Arabian horse were training and submitted to Standard Incremental Exercise Test on high-speed equine treadmill. Venous blood samples were taken before exercise, immediately and 30 min, 60min, 3h, 6h, 24h, 3 days and 5 days after exercise. The serum activity aspartate aminotransferase, creatine kinase and lactate dehydrogenase were determined. The serum activies of AST, CK and LDH increase immediately and returned to baseline value 30 minutes after exercise. The AST enzyme activity increased at 12 hours and 24 hours, CK at 3 hours and 6 hours, and LDH at 24 hours after Standard Incremental Exercise Test.

Polyethylene gel in the subcutaneous tissue of rats: Histopathologic and systemic evaluation

Purpose: To evaluate the histological and systemic response to subcutaneous injection of polyethylene gel in rats. Methods: Twenty-one white male rats were divided into 3 groups (G): G1 and G2 received subcutaneous polyethylene gel injection in the dorsal midline and were sacrificed at 30 and 60 postoperative days, respectively. G3 was not exposed to the polyethylene gel and was sacrificed after 60 days. Blood levels of lactate dehydrogenase (LDH), creatine kinase (CK), and alkaline phosphatase (ALP) were evaluated. The heart, kidney, liver, adrenal gland, injection site, and adjacent tissues were histologically examined. The results were submitted to statistical analysis. Results: There was no clinical evidence of extrusion, reduction of the injected volume, or abnormalities in the adjacent tissues. Blood levels of CK and LDH were normal and similar in all groups. ALP levels were significantly lower in G2 than in G1 and G3. The systemic organs were normal on histological examination in the 3 groups evaluated. Microscopically, the polyethylene gel was surrounded by a thin pseudocapsule formation and minimal inflammatory cell response, which decreased from G1 to G2. Conclusion: The subcutaneous injection of polyethylene gel in rats elicited minimal local inflammatory response and no systemic side effects. Copyright © 2008 Informa Healthcare USA, Inc.

Anthracycline-induced cardiotoxicity

The anthracyclines constitute a group of drugs widely used for the treatment of a variety of human tumors. However, the development of irreversible cardiotoxicity has limited their use. Anthracycline-induced cardiotoxicity can persist for years with no clinical symptoms. However, its prognosis becomes poor after the development of overt heart failure, possibly even worse than ischemic or idiopathic dilated cardiomyopathies. Due to the successful action of anthracyclines as chemotherapic agents, several strategies have been tried to prevent/ attenuate their side effects. Although anthracycline-induced injury appears to be multifactorial, a common denominator among most of the proposed mechanisms is cellular damage mediated by reactive oxygen species. However, it remains controversial as to whether antioxidants can prevent such side effects given that different mechanisms may be involved in acute versus chronic toxicity. The present review applies a multisided approach to the critical evaluation of various hypotheses proposed over the last decade on the role of oxidative stress in cardiotoxicity induced by doxorubicin, the most used anthracycline agent. The clinical diagnosis and treatment is also discussed. © 2008 Bentham Science Publishers Ltd.

Polineuropatia associada a hipotireoidismo em cães: Relato de seis casos

Six Doberman Pinscher, between six and eight years of age, were presented to the Veterinary Hospital from Faculty of Veterinary Science of The University of Buenos Aires. Neurological examination revealed tetraparesis with inability to walk, decreased muscle tonus and myotatic reflexes in all dogs. Serum cholesterol levels, creatine kinase and alkaline phosphatase activities were mildly to markedly elevated, and tibial motor nerve conduction velocities were slow in all dogs. Basal measurements of free T4 and TSH were determined by radioimmunoassay. Although fT4 values were within normal range, in all dogs TSH values were elevated. Based on this results, hypothyroidism was diagnosed and a supplementation therapy was established with oral levothyroxine (T4). Two weeks after treatment has been started, all patients had an improvement in clinical signs, and within a month gait became normal, as well as muscular tonus and spinal reflexes.

Efeito da suplementação com selênio sobre a concentração sérica de creatina kinase em bovinos

The study, evaluated the addition of different concentrations of Se in mineral mixture affecting creatine kinase (CK) serum concentrations in cattle. 60 male, Nellore cattle, at about 12 months old, were randomly assigned to groups (15 calves/ group), Gc, G3,6, G5,4 or G6,4 (0, 3.6, 5.4, and 6.4 mg Se/bovine/day). The levels of serum CK in the cattle were not affected by neither the interaction selenium concentration x time nor the concentration of supplementation. However, CK levels increased over the experiment irrespective of dietary selenium concentration. In addition, the frequency of animals with CK levels above normal increased (p<0.10) in group G6,4. The concentrations of selenium studied here do not affect serum CK in cattle, but the daily concentration of 6.4 mg selenium is not recommended because it is possibly toxic effect.

Anestesia para colecistectomía videolaparoscópica en paciente portador de enfermedad de Steinert. Relato de caso y revisiõn de la literatura

BACKGROUND AND OBJECTIVES: Myotonic dystrophies are autosomal dominant neuromuscular diseases. Among them, myotonic dystrophy type 1 (MD1), or Steinert disease, is the most common in adults, and besides muscular involvement it also has important systemic manifestations. Myotonic dystrophy type 1 poses a challenge to the anesthesiologist. Those patients are more sensitive to anesthetics and prone to cardiac and pulmonary complications. Besides, the possibility of developing malignant hyperthermia and myotonic episodes is also present. CASE REPORT: This is a 39-year old patient with DM1 who underwent general anesthesia for videolaparoscopic cholecystectomy. Total intravenous anesthesia with propofol, remifentanil, and rocuronium was the technique chosen. Intercurrences were not observed in the 90-minute surgical procedure, but after extubation, the patient developed respiratory failure and myotonia, which made tracheal intubation impossible. A laryngeal mask was used, allowing adequate oxygenation, and mechanical ventilation was maintained until full recovery of the respiratory function. The patient did not develop further complications. CONCLUSIONS: Myotonic dystrophy type 1 presents several particularities to the anesthesiologist. Detailed knowledge of its systemic involvement along with the differentiated action of anesthetic drugs in those patients will provide safer anesthetic-surgical procedure.

Involvement of organic systems in golden retriever X-linked muscular dystrophy

Duchenne muscular dystrophy is a lethal genetic disease characterized by progressive muscle degeneration that usually had been used the Golden Retriever as a model for studying the disease (GRMD - Golden Retriever Muscular Dystrophy). A total of 16 male dystrophic Golden Retrievers dogs between 5 to 51 months of age were examined in the present study. The animals were classified as dystrophic according to two simultaneous complementary criteria: genotypic analysis and serum creatine kinase levels. The macroscopic abnormalities of the different organs and tissues and histopathological features were described using hematoxylin-eosin. The lesions in the skeletal muscles associated with the digestive problems resulted in cachexia with different intensities in all the dystrophic dogs. Cardiac muscle involvement was found in 87,5% of the GRMD dogs resulting, however, in cardiac failure in only 18,8% of the animals. The musculature of the diaphragm was hypertrophic in all affected animals resulting in progressive respiratory muscle weakness and at later stages in respiratory failure (81,25%). The liver abnormalities found in dystrophic dogs were originated mainly from heart disease and developed progressively. Hyperemia of mucosa and granular material indicated changes in the functioning and emptying of bladder. The germinative lineage cells presented moderate to severe degeneration probably due to degeneration of the scrotum and cremaster muscle which prevented the proper thermo-regulation of the testicle. Our results highlight the fact that there is significant impairment of the cardiac, respiratory and skeletal muscle systems in GRMD dogs since the age of five months. In addition, significant alterations of the gastrointestinal tract, urinary and reproductive systems are indicating the presence of degenerative lesions in the smooth musculature.

Indicadores bioquímicos séricos e do líquido peritoneal de equinos submetidos à obstrução intestinal

Twenty-four horses were distributed into four different groups, instrumented control (GI), duodenum obstruction (GII), ileum obstruction (GIII) and large colon obstruction (GIV). Serum and peritoneal fluid analysis of aspartate aminotransferase, creatine kinase, lactate dehydrogenase, alkaline phosphatase, inorganic phosphorus and lactate were measured. Samples were collected one hour before the surgical procedure (T0); 3 hours after the obstruction (T3ob), 1, 3, 12, 24, 120 and 168 hours after the beginning of reperfusion/deobstruction. Duodenal (GII) and ileum (GIII) obstructions changed serum and peritoneal fluid biochemical analysis. However, only lactate, lactate dehydrogenase, creatine kinase and inorganic phosphorus concentrations were abnormal in peritoneal fluid three hours after the obstruction. The biochemical analysis of peritoneal fluid allowed a faster diagnostic of intestinal alterations than the serum analysis; hence it should be prioritized when pre-operatory colic assessment is carried out.

Biocompatible microemulsion modifies the pharmacokinetic profile and cardiotoxicity of doxorubicin

Doxorubicin (DOX) is an anthracycline antibiotic with a broad antitumor spectrum. However, the clinical use of DOX is limited because of its cardiotoxicity, a dose-dependent effect. Colloidal drug delivery systems, such as microemulsions (MEs), allow the incorporation of drugs, modifying the pharmacokinetic (PK) profile and toxic effects. In this study, we evaluated the PK profile and cardiotoxicity of a new DOX ME (DOX-ME). The PK profile of DOX-ME was determined and compared with that of the conventional DOX after single-dose administration (6mg/kg, intravenous) in male Wistar rats (n = 12 per group). The cardiotoxicity of DOX formulations was evaluated by serum creatine kinase MB (CKMB) activity in both animal groups before and after drug administration. The plasma DOX measurements were performed by high-performance liquid chromatography with fluorescence detection, and the CKMB levels were assayed using the CKMB Labtest® kit. The ME system showed a significant increase in plasma DOX concentrations and lower distribution volume when compared with conventional DOX. Serum CKMB activity increased after conventional DOX administration but was unchanged in the DOX-ME group. These results demonstrate modifications in drug access to susceptible sites using DOX-ME. DOX-ME displayed features that make it a promising system for future therapeutic application. © 2012 Wiley Periodicals, Inc.

Monitoring chronic physical stress using biomarkers, performance protocols and mathematical functions to identify physiological adaptations in rats

This study was undertaken to characterize the effects of monotonous training at lactate minimum (LM) intensity on aerobic and anaerobic performances; glycogen concentrationsin the soleus muscle, the gastrocnemius muscle and the liver; and creatine kinase (CK), free fatty acids and glucose concentrations in rats. The rats were separated into trained (n =10), baseline (n = 10) and sedentary (n=10) groups. The trained group was submitted to the following: 60 min/day, 6 day/week and intensity equivalent to LM during the 12-week training period. The training volume was reduced after four weeks according to a sigmoid function. The total CK (U/L) increased in the trained group after 12 weeks (742.0±158.5) in comparison with the baseline (319.6±40.2) and the sedentary (261.6+42.2) groups. Free fatty acids and glycogen stores (liver, soleus muscle and gastrocnemius muscle) increased after 12 weeks of monotonous training but aerobic and anaerobic performances were unchanged in relation to the sedentary group. The monotonous training at LM increased the level of energy substrates, unchanged aerobic performance, reduced anaerobic capacity and increased the serum CK concentration; however, the rats did not achieve the predicted training volume.