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Relationship between cirrhosis and renal dysfunction is not yet fully understood. A model of cirrhosis with acute hepatic and renal damage (RF), produced by CCl 4 in rats, with hemodynamic and renal functional alterations, similar to those observed in decompensated cirrhosis (DC) in man, was used to study chemical nephrotoxicity in animals. We performed in male Wistar rats hepatic and renal functional and hemodynamic studies in control, cirrhotic and decompensated cirrhotic (DC) groups. Cirrhosis was induced with carbon tetrachloride by chronic administration. Association between liver and renal functional alterations was detected in rats with decompensated cirrhosis, showing fall in mean arterial pressure and reduction of glomerular filtration rate and filtration fraction. Renal hemodynamics did not change in cirrhotic rats, similarly to what occurs in compensated cirrhotic patients. However, DC rats exhibited increased sodium, glucose and phosphate urinary excretions and decreased ATP in renal cortex. DC animals had severe hypoglycemia. There was an extensive liver fibrosis. Glomeruli had hypercellularity and tubules showed extensive vacuolization in cirrhotic and DC rats. The present study suggests that in this model, damage typical of acute tubular necrosis ensues in cirrhotic rats. We describe functional and morphological damage in liver and kidney in a model of cirrhosis that might predispose to the development of acute renal failure when an individual with hepatic damage is exposed in acute way to chemical toxicants.

A sample of 182 physicians from 17 counties of southwest central and northwest in Florida is employed to investigate the psychometric properties of the Stamps and Cruz Physicians’ Satisfaction Scale. An analysis utilizing exploratory and confirmatory factor analysis suggests a shortened version of the scale consisting of 19 items and five dimensions. This scale, labeled PS-SV (for physicians satisfaction, shortened version) is recommended for future applications.

Administration of ethanol (8%) or acetone (1%) to nursing dams in the drinking water, for 10 days, increased the nephrotoxicity of paracetamol (APAP) in the 14-day-old lactating offspring. The percentage of proximal tubular cells with evidence of necrotic damage in male rats was higher in those animals that received APAP (500 mg/kg, i.p.) and whose nursing rats were exposed to ethanol (25.0 ± 8.4%) or acetone (17.2 ± 1.2%), than in the group treated with APAP alone (10.6 ± 1.6%). The activity of urinary N-acetylglucuronidase was also significantly higher in the rats exposed translactationally to ethanol or acetone than in animals treated with the APAP alone. Nephrotoxicity showed a sexual dimorphic pattern with a higher toxicity in male than in female rats. The percentage of necrotic tubules in the male rats not exposed to inductor was 10.6 ± 1.6%, and in female rats 5.0 ± 1.4% (p < 0.05). Animals exposed to ethanol or acetone and treated with APAP showed less weight gain than the group treated only with APAP. Our results suggest that renal toxicity is enhanced in the nursing animals that were exposed, via maternal milk, to ethanol or acetone (inductors of cytochrome P4502E1), than in the control animals. This circumstance may be relevant in alcoholic women while they are lactating.

1. 1. Acute effects of Karwinskia humboldtiana (Kh) were studied in some renal functions and structural patterns of renal tissue. 2. 2. Haemodinamic changes were observed with decrements of the glomerular filtration rate, renal plasma flow and filtration fraction during acute intoxication. 3. 3. A marked increment in the fractional excretion of sodium was observed in the rats treated with tullidora fruits ( Kh ). 4. 4. Cloudy swelling and hydropic degeneration was seen 72 hr after intoxication, mainly in the proximal convoluted tubules.

Aguascalientes is a state located in Central Mexico, with a surface area of 5,589 km2 (0.3 per cent of Mexican territory; CONAGUA, 2000). Most of the state of Aguascalientes (87 per cent) has a semi-dry climate, with annual average precipitation of 600 mm (rainy season in the summer) and an annual average temperature of 18°C. Some locations in Aguascalientes (13 per cent) have a warm sub-humid climate, with an annual average precipitation of 700 mm, and an annual average temperature of 16°C. The annual average precipitation in the state is 552 mm, with rainfall (80 per cent) predominant between June and September (CONAGUA, 2004).

Aflatoxins (AF) have a high impact in both human and animal health, causing significant economic losses in the poultry industry, especially by diminution of avian growth, feed efficiency, and product quality. Aflatoxins affect the whole organism, particularly liver and kidney. The objective of this study was to evaluate renal function alterations in laying hens during chronic AF ingestion. Randomly, 84 Leghorn Hy-Line laying hens (13 wk old) were assigned into 4 experimental groups (n = 21): 0.0, 0.5, 1.0, and 1.5 mg of AF/kg of feed. The AF (B(1), B(2), G(1), and G(2)) was obtained from 2 toxicogenic local strains of Aspergillus flavus grown in corn grains; the grain was sterilized, ground, and added to basal diets to achieve the selected AF concentrations. Hens ingested, during 17 and 42 wk, feed contaminated with AF. Data were analyzed in a 4 x 2 factorial arrangement. Hens were anesthetized, ureteral urine samples were collected, and arterial blood samples were taken. The renal functional tests were evaluated by spectrophotometric and flame photometric methods, including a) Na, K, Ca, and phosphate fractional excretions; b) renal hemodynamic studies, glomerular filtration rate and renal plasma flow by inulin and p-aminohippurate clearances, respectively; and c) identification of macroscopic and histopathologic lesions. The hens intoxicated at all levels of AF showed significant (P < 0.05) increases in Ca, Na, and phosphate fraction excretions. Sodium and phosphates were excreted in a pattern of response time-dose. However, glomerular filtration rate exhibited a significant reduction (P < 0.05). The K fractional excretion and renal plasma flow remained unchanged. These results suggest that AF chronic ingestion affects renal functions of laying hens and induces Ca(++), (-3)PO(4), and Na(+) losses, which are of great concern to the poultry industry.

Functional and morphological alterations were generated by p.o. (per os) administration of a single oral dose of carbon tetrachloride (CCl4; 0.125 mL/kg b.w., equivalent to 293 mg/kg) to adult male Wistar rats. CCl4 significantly increased (p < 0.05) the serum activities of alanine aminotransferase (ALT; 7478 ± 1044%) and aspartate aminotransferase (AST; 6964 ± 833%), compared to control rats; CCl4 also significantly decreased serum concentration of albumin (23 ± 5.5%) and increased the concentration of malondialhdeyde (MDA) in liver (300 ± 33%). Furthermore, CCl 4 down-regulated the mRNA steady-state level of tumor necrosis factor a(TNF-a). CCl4 produced necrosis in the central lobe area, extended to the periphery, nuclear alterations (pycnosis, karyolysis and karyorrhexis), and cytoplasmic acidophilia. The pretreatment with 4 mg/kg (p.o.) of Ginkgo biloba extract (GbE), for 5 days, prevented most of the damage caused by CCl4: significantly decreased the serum activities of ALT and AST (54 and 65%, respectively), compared to CCl4-treated rats; GbE partially prevented the increase of liver MDA (55 ± 14%) and the decrease of albumin concentration to 12 ± 0.2%. This pretreatment prevented the down-regulation of TNF-a and up-regulated the interleukine 6 (IL-6) mRNA steady-state level. Moreover, the GbE reduced the amount of necrotic areas in the central lobe area, compared to CCl4-treated rats.

Implantation methods for commercially available heart valve prostheses require open-chest access to the heart to perform the suturing process. In order to alleviate this complicated surgical implant technique, a “stent-valve” design was developed that will provide a less cumbersome implantation method and therefore a less invasive access to the heart. The purpose of this study is to verify its hydrodynamic performance and migration characteristics to assess its feasibility for use as a replacement heart valve. Hydrodynamic evaluation of the novel stent-valve combination device was carried out using a Vivitro left heart simulator and by setting up a comparison with the same 19 mm trileaflet valve under a traditional implantation (suture) method. To assess implantation ability under normal physiological conditions, porcine aortic root tissue was mounted into the left heart simulator to replace the original glass sinus. A comparison experiment was conducted to study the change in the total compliance and resistance of the testing system using the modified Windkessel model. For the range of test conditions investigated, the stent-valve combination device produced an average pressure gradient of 41.2 mm Hg(±19.6 mm Hg), an average effective orifice area (EOA) of 1.06 cm2(±0.08 cm2), and an average regurgitation percentage of 4.5% (±3.3%), while the sutured valve produced an average pressure gradient of 48.7 mm Hg(±17.4 mm Hg), an average EOA of 0.88 cm2(±0.14 cm2), and an average regurgitation percentage of 0.8% (±0.4%). The total compliance and resistance of the system was 0.37 ml/mm Hg(±0.01 ml/mm Hg) and 1.1 mm Hg/ml/s(±0.29 mm Hg/ml/s), with the original Windkessel model, and 0.33 ml/mm Hg(±0.01 ml/mm Hg) and 1.1 mm Hg/ml/s(±0.24 mm Hg/ml/s) for the system with the aortic tissue. The stent-valve combination device has demonstrated favorable hydrodynamic performance when compared with the same trileaflet valve under the traditional suturing method, and the arterial stent makes it possible to secure the valve at its required position without migration.

1. The effects of reduction in renal blood flow (RBF) on urinary acidification and proximal tubule H+ ion secretion were studied after partial aortic clamping in rats. 2. Acute reduction of the renal perfusion pressure (from 109 +/- 3.88 to 77.4 +/- 1.05 mmHg) decreased both inulin and PAH (p-aminohippurate) clearances to about one-third of their control values. Absolute levels of urinary sodium excretion also decreased markedly, but fractional sodium excretion did not change significantly. 3. Urine pH and bicarbonate levels were not affected, but titratable acidity increased significantly from 0.12 +/- 0.011 to 0.25 +/- 0.042 muequiv min-1 ml-1 glomerular filtration rate (GFR). During aortic clamping, cortical PCO2 as determined by means of Severinghaus microelectrodes was reduced by a mean value of 7.0 +/- 1.5 mmHg. 4. Proximal tubule acidification kinetics were studied by stationary microperfusion techniques in which the time course of pH changes was monitored by pH microelectrodes. Steady-state pH fell from a mean control value of 6.77 +/- 0.03 to 6.65 +/- 0.02, and stationary bicarbonate concentrations from 4.70 +/- 0.27 to 2.84 +/- 0.18 mM. Acidification half-time decreased from 5.07 +/- 0.30 to 4.39 +/- 0.19 s, and net bicarbonate reabsorption increased from 1.63 +/- 0.14 to 1.99 +/- 0.12 nmol cm-2 s-1, these changes being statistically significant. 5. The experiments demonstrate that both overall acid excretion and proximal acid secretion are not compromised by a large decrease of RBF to about one-third of the control value; titratable acid excretion and proximal net bicarbonate reabsorption were even moderately increased under these conditions.

Our previous acute toxicity studies with Karwinskia humboldtiana (Kh) in rats showed renal hemodynamic changes with a marked increase in the fractional excretion of sodium and morphological damage. To analyse the effects of Kh or 'tullidora' on energetic metabolism, a single dose of an oral preparation from the seed fruits was given to Wistar rats (1.25 g/kg). In tullidora-treated rats there was 8% mortality. ATP concentrations in renal tissue decreased significantly (control: 53.85+/-3.34, tullidora 38.28+/-5.31 micromol/g fresh tissue, P0.05). Total blood (54.8+/-0.96, tullidora: 40.2+/-1.55 micromol/dL, P0.01) and haemoglobin-ATP concentrations (3.69+/-0.12, tullidora: 2.56+/-0.11 micromol/g, P0.01) were also significantly diminished. Moreover, the total protein in renal cortex from tullidora-treated rats decreased as compared to control group (control: 71.43+/-2.88, tullidora: 55.20+/-4.06 mg/g fresh tissue, P0.05). In contrast, Na+-K+-ATPase activity in tullidora-treated animals was not different from control rats. These findings might partially explain the acute effects and mortality observed in the Kh treated rats.

This research examines the effect of practice arrangements on five dimensions of physicians' satisfaction (i.e., personal factors, resources, peer review, profession, and state regulations) and the moderating effect of job autonomy and decision making on this relationship. This research finds that physicians who work for HMOs and hospitals are more satisfied with job resources, regulatory climate, and their professions, compared with physicians who are self-employed (solo and group practices). Physicians who work for HMOs and hospitals have less autonomy and decision-making power, compared with self-employed physicians. Also, job autonomy partially moderates the relationship between organizational arrangement and physicians' satisfaction with job resources and satisfaction with the profession. Decision making does not moderate the organizational arrangement and physicians' satisfaction relationship.

Severe pre-eclampsia reduced significantly (P

Aflatoxin B(1) (AFB(1)) negatively affects chicken (Gallus domesticus) growth. This effect is more severe during development. We studied the influence of age on the toxic effects of AFB(1) on plasma, renal and hepatic enzymes, under two protocols, in adult and in developing Arbor-Acres chickens. Protocol A: 100 male 4-week-old chickens (640 g), received AFB(1), 0.5, 1.0, or 2.0 microg/g of feed (daily p.o.), a fourth group received an aflatoxin-free diet. Five birds/group were slaughtered at 7, 14, 21 and 28 days of treatment. Body, hepatic and renal weights, succinate-dehydrogenase (SDH) and glutamate-dehydrogenase (GluDH) in plasma and liver were measured. Hepatic SDH and GluDH decreased (P

The effects of cyclosporin A (CyA, 50 mg/kg body weight) or its commercial vehicle (cremophor) on the acid-base regulation of uninephrectomized rats were assessed for 7 days and in non-nephrectomized rats for 15 days. CyA induced a marked systemic acidosis, accompanied by decreases in blood PCO(2) and plasma bicarbonate. Untreated uninephrectomized rats did not show the acidosis. In CyA-treated rats the urine pH decreased (control 6. 65+/-0.06 vs. CyA 6.18+/-0.08; P0.01) as well as urinary bicarbonate (non-nephrectomized rats 7.50+/-1.88 mM vs. uninephrectomy plus CyA 0.75+/- 0.06 mM; P0.01), suggesting partial renal compensation of systemic acidosis. Titratable acidity increased in CyA-treated rats (control 21.6+/-1.2 vs. CyA 63.3+/-12.0 microEq/l; P0.001). Phosphate, glucose, and osmolar clearances were not significantly altered in non-nephrectomized rats treated with CyA for 15 days. There was a striking decrease in body weight in CyA-treated rats (control 274.0+/-3.8 vs. CyA 225.0+/-5.1 g; P0. 01), but compensatory growth of the remaining kidney was not prevented by this drug or by its vehicle. In summary, CyA induced a severe metabolic acidosis in uninephrectomized rats that was not compensated by the remaining kidney, in spite of the well-preserved compensatory weight gain of this organ. Loss of body weight was significant in CyA-treated animals.

Industrial development has resulted in an increased release of chemicals and other agents into the environment, resulting in damage to the environment as well as increasing the risk of adverse effects on human health. Environmental toxicology (ET) is the discipline responsible for assessing the risks to human health and the environment from the effects of new chemicals and those already present in the environment. The development of human resources in toxicology is therefore a priority in both Latin America (LA) and the European Union (EU), although LA professionals are more involved in risk evaluation than in risk assessment compared to their EU colleagues. A solid background in general toxicology will enable those interested in environmental issues to tackle local problems. Moreover, the increasing globalization of markets and, therefore, of the necessary regulations, requires harmonisation of postgraduate programmes to ensure that risk assessment and management related to the environment are dealt with uniformly and by highly qualified scientists. The Inaugural Meeting of the ALFA-OMET Toxicology', a 2-year programme supported by the European Commission, offered the opportunity to discuss a number of these issues. The present status of existing ET courses in the EU and LA and the corresponding professional profiles in the two regions were examined, and a harmonized academic curriculum for a postgraduate professional profiles in the two regions were examined, and a harmonized academic curriculum for a postgraduate course in environmental toxicology was developed. Finally, a course programme for toxicology and a specialization in environmental toxicology designed by a panel of experts was discussed, and its relevance as a model for other specialisation programmes was analysed. Exercises such as those performed by ALFA-OMET may be useful not only in promoting discussion for the implementation of national and international professional registers in LA, but also in encouraging the same, ongoing process in the EU.

The effect of in utero exposure to parathion was assessed in offspring from dams treated with low doses of parathion during gestation. An analytical method to measure parathion in small blood samples (200 μl) was used which prevented significant bleeding during sampling. Pharmacokinetic studies were performed in anesthetized 6-week-old male rats and showed a monoexponential pattern of elimination. The offspring exposed in utero to parathion depicted a higher plasma disposition rate of the insecticide than the control group (T1/2e1 60 ± 18.2 and 24.8 ± 13.1 min, respectively; p < 0.05), suggesting the presence of some adaptive mechanism. This mechanism might render the in utero exposed animal less liable to the toxic effects of this pesticide during the postnatal life. The increase observed in the elimination rate does not seem to be due to higher secretory activity of the kidney, and metabolic mechanisms might be involved.

The effects of ethyl parathion on the activities of various renal enzymes were studied in the offspring from dams treated with this insecticide during pregnancy. The enzymes tested were the (Na+-K+)- and the Mg2+-dependent ATPases, the glutathione S-transferases and carboxylesterases. The postnatal effects of parathion on kidney ATPases from undernourished rats were also assessed. The organophosphate was administered per os to pregnant rats at a dose of 1 mg kg−1 body weight per day throughout gestation, and suspended after delivery. The offspring were divided in groups of normally-fed and undernourished rats. In the undernourished group, food restriction produced a decrease of 43% in body weight as compared to the normally-fed group. Offspring were sacrificed 6 weeks after birth and the enzymatic activities were determined in kidney homogenates. We found a decrease in the enzymatic activity of total ATPases, at the expense of the Mg2+-dependent ATPase. However, the activities of the (Na+-K+)-dependent ATPase, the glutathione S-transferases and the carboxylesterases did not show significant changes. On the other hand, undernutrition did not potentiate the effects of parathion on the ATPases. Thus, this organophosphate administered during pregnancy produced a selective inhibition on the renal Mg2+ -dependent ATPase from offspring, which was not potentiated by our undernutritional model.

The kidney's responsiveness to male sexual hormones has been often neglected. Renal secretion of organic anions is higher in male than in female individuals; as a consequence, most of the xenobiotics that are excreted from the organism through this pathway are eliminated more rapidly by males than by female animals. To gain further insight into this issue, we studied in vitro and in vivo characteristics of the transport of p-aminohippurate (PAH), a suitable marker for this system, in male and female rats, under different hormonal conditions. Kinetics of PAH showed a shorter elimination half-time in male than in female rats (t(1/2el): male = 16.2 +/- 2.1 min, female = 25.7 +/- 4.5 min, P0.05). Castration of male rats increased t(1/2el) to a value similar to that of female rats (t(1/2el): orchiectomized rat = 28.1 +/- 7.1 min). Testosterone treatment of female rats increased the elimination rate to a value similar to that of male rats. In vitro PAH uptake by renal cortical slices from intact male rats was higher than that by slices from orchiectomized rats. Kinetic analyses of PAH uptake suggest that the difference was caused by a lower number of transporting molecules in orchiectomized than in intact animals, whereas the transporting capacity for each carrier was similar in male and in orchiectomized rats. Our results suggest that testosterone increases the number of functional carriers for PAH in the kidney.

Introducción: en pacientes sometidos a trasplantes de órganos sólidos, la tuberculosis continúa siendo una complicación frecuente, especialmente en los países con alta endemia.Objetivo: determinar la presentación de tuberculosis en los pacientes sometidos a trasplante de órganos sólidos, describir sus características demográficas y su evolución y revisar la literatura científica.Materiales y métodos: se trata de una serie retrospectiva de casos de tuberculosis en pacientes sometidos a trasplante cardiaco o renal, entre junio del 2004 y abril del 2011 en el Hospital Universitario San Ignacio de Bogotá, Colombia. Se determinaron sus características clínicas, su evolución y resultado.Resultados: de 187 pacientes sometidos a trasplante de órganos sólidos, en tres se diagnosticó tuberculosis (dos casos de tuberculosis pulmonar y uno por diseminación hematógena en pacientes con trasplante renal y cardiaco). En uno de ellos se presentó histoplasmosis pulmonar asociada. Un paciente falleció durante el tratamiento antituberculoso.Conclusiones: los pacientes en lista de espera para trasplante deben ser evaluados para tuberculosis latente, dada la prevalencia de la enfermedad en nuestro país. Además, los pacientes con trasplante tienen mayor riesgo de contraer infecciones, lo cual se debe tener en cuenta entre los diagnósticos diferenciales de las enfermedades infecciosas respiratorias.