988 resultados para Fecal steroids
Resumo:
FTY720 is a new and effective immunosuppressive agent, which produces peripheral blood lymphopenia through a lymphocyte homing effect. We investigated the relationship between the dose of FTY720 or blood concentration (pharmacokinetics, PK) and peripheral lymphopenia (pharmacodynamics, PD) in 23 kidney transplant recipients randomized to receive FTY720 (0.25-2.5 mg/day) or mofetil mycophenolate (2 mg/day) in combination with cyclosporine and steroids. FTY720 dose, blood concentrations and lymphocyte counts were determined weekly before and 4 to 12 weeks after transplantation. The effect of PD was calculated as the absolute lymphocyte count or its reductions. PK/PD modeling was used to find the best-fit model. Mean FTY720 concentrations were 0.36 ± 0.05 (0.25 mg), 0.73 ± 0.12 (0.5 mg), 3.26 ± 0.51 (1 mg), and 7.15 ± 1.41 ng/ml (2.5 mg) between 4 and 12 weeks after transplantation. FTY720 PK was linear with dose (r² = 0.98) and showed low inter- and intra-individual variability. FTY720 produced a dose-dependent increase in mean percent reduction of peripheral lymphocyte counts (38 vs 42 vs 56 vs 77, P < 0.01, respectively). The simple Emax model [E = (Emax * C)/(C + EC50)] was the best-fit PK/PD modeling for FTY720 dose (Emax = 87.8 ± 5.3% and ED50 = 0.48 ± 0.08 mg, r² = 0.94) or concentration (Emax = 78.3 ± 2.9% and EC50 = 0.59 ± 0.09 ng/ml, r² = 0.89) vs effect (% reduction in peripheral lymphocytes). FTY720 PK/PD is dose dependent and follows an Emax model (EC50 = 0.5 mg or 0.6 ng/ml). Using lymphopenia as an FTY720 PD surrogate marker, high % reductions (~80%) in peripheral lymphocytes are required to achieve best efficacy to prevent acute allograft rejection.
Resumo:
We evaluated the prevalence of low bone mineral density (BMD) and osteoporotic fractures in kidney transplantation (KT) patients and determined risk factors associated with osteoporotic fractures. The study was conducted on 191 patients (94 men and 97 women) with first KT for 3 years or more presenting stable and preserved renal function (serum creatinine levels lower than 2.5 mg/dl). KT patients were on immunosuppressive therapy and the cumulative doses of these drugs were also evaluated. BMD was determined by dual-energy X-ray absorptiometry at multiple sites (spine, femur and total body). Quantitative ultrasound of the calcaneus (broadband ultrasound attenuation, speed of sound, and stiffness index, SI) was also performed. Twenty-four percent (46) of all patients had either vertebral (29/46) or appendicular (17/46) fractures. We found osteoporosis and osteopenia in 8.5-13.4 and 30.9-35.1% of KT patients, respectively. Women had more fractures than men. In women, prevalent fractures were associated with diabetes mellitus [OR = 11.5, 95% CI (2.4-55.7)], time since menopause [OR = 3.7, 95% CI (1.2-11.9)], femoral neck BMD [OR = 1.99, 95% CI (1.4-2.8)], cumulative dose of steroids [OR = 1.1, 95% CI (1.02-1.12)] and low SI [OR = 1.1, 95% CI (1.0-1.2)]. In men, fractures were associated with lower lumbar spine BMD [OR = 1.75, 95% CI (1.1-2.7)], lower SI [OR = 1.1, 95% CI (1.03-1.13)], duration of dialysis [OR = 1.3, 95% CI (1.13-2.7)], and lower body mass index [OR = 1.24, 95% CI (1.1-1.4). Our results demonstrate high prevalence of low BMD and osteoporotic fractures in patients receiving a successful kidney transplant and indicate the need for specific intervention to prevent osteoporosis in this population.
Resumo:
Decrease in microbial contacts in affluent societies is considered to lie behind the rise in allergic and other chronic inflammatory diseases during the last decades. Indeed, deviations in the intestinal microbiota composition and diversity have been associated with several diseases, such as atopic eczema. However, there is no consensus yet on what would constitute a beneficial or harmful microbiota. The aim of this thesis was to study the microbiota development in healthy infants and to characterize intestinal microbiota signatures associated with disease status and severity in infants with atopic eczema. The methodological aim was to compare and optimize methods for DNA extraction from fecal samples to be used in high-throughput microbiota analyses. It was confirmed that the most critical step in successful microbial DNA extraction from fecal samples is the mechanical cell lysis procedure. Based on this finding, an efficient semi-automated extraction process was developed that can be scaled for use in high-throughput platforms such as phylogenetic microarray used in this series of studies. By analyzing a longitudinal motherchild cohort for 3 years it was observed that the microbiota development is a gradual process, where some bacterial groups reach the degree of adult-type pattern earlier than others. During the breast-feeding period, the microbiota appeared to be relatively simple, while major diversification was found to start during the weaning process. By the age of 3 years, the child’s microbiota composition started to resemble that of an adult, but the bacterial diversity has still not reached the full diversity, indicating that the microbiota maturation extends beyond this age. In addition, at three years of age, the child’s microbiota was more similar to mother’s microbiota than to microbiota of nonrelated women.In infants with atopic eczema, a high total microbiota diversity and abundance of butyrate-producing bacteria was found to correlate with mild symptoms at 6 months. At 18 months, infants with mild eczema had significantly higher microbiota diversity and aberrant microbiota composition when compared to healthy controls at the same age. In conclusion, the comprehensive phylogenetic microarray analysis of early life microbiota shows the synergetic effect of vertical transmission and shared environment on the intestinal microbiota development. By the age of three years, the compositional development of intestinal microbiota is close to adult level, but the microbiota diversification continues beyond this age. In addition, specific microbiota signatures are associated with the existence and severity of atopic eczema and intestinal microbiota seems to have a role in alleviating the symptoms of this disease.
Resumo:
Elevated blood cholesterol is an important risk factor associated with atherosclerosis and coronary heart disease. Several studies have reported a decrease in serum cholesterol during the consumption of large doses of fermented dairy products or lactobacillus strains. The proposed mechanism for this effect is the removal or assimilation of intestinal cholesterol by the bacteria, reducing cholesterol absorption. Although this effect was demonstrated in vitro, its relevance in vivo is still controversial. Furthermore, few studies have investigated the role of lactobacilli in atherogenesis. The aim of the present study was to determine the effect of Lactobacillus delbrueckii on cholesterol metabolism in germ-free mice and the possible hypocholesterolemic and antiatherogenic action of these bacteria using atherosclerosis-prone apolipoprotein E (apo E) knock-out (KO) mice. For this purpose, Swiss/NIH germ-free mice were monoassociated with L. delbrueckii and fed a hypercholesterolemic diet for four weeks. In addition, apo E KO mice were fed a normal chow diet and treated with L. delbrueckii for 6 weeks. There was a reduction in cholesterol excretion in germ-free mice, which was not associated with changes in blood or liver cholesterol concentration. In apo E KO mice, no effect of L. delbrueckii was detected in blood, liver or fecal cholesterol. The atherosclerotic lesion in the aorta was also similar in mice receiving or not these bacteria. In conclusion, these results suggest that, although L. delbrueckii treatment was able to reduce cholesterol excretion in germ-free mice, no hypocholesterolemic or antiatherogenic effect was observed in apo E KO mice.
Resumo:
The present study investigated the effects of exercise and anabolic-androgenic steroids on cardiac HSP72 expression. Male Wistar rats were divided into experimental groups: nandrolone exercise (NE, N = 6), control exercise (CE, N = 6), nandrolone sedentary (NS, N = 6), and control sedentary (CS, N = 6). Animals in the NE and NS groups received a weekly intramuscular injection (6.5 mg/kg of body weight) of nandrolone decanoate, while those in the CS and CE groups received mineral oil as vehicle. Animals in the NE and CE groups were submitted to a progressive running program on a treadmill, for 8 weeks. Fragments of the left ventricle were collected at sacrifice and the relative immunoblot contents of HSP72 were determined. Heart weight to body weight ratio was higher in exercised than in sedentary animals (P < 0.05, 4.65 ± 0.38 vs 4.20 ± 0.47 mg/g, respectively), independently of nandrolone, and in nandrolone-treated than untreated animals (P < 0.05, 4.68 ± 0.47 vs 4.18 ± 0.32 mg/g, respectively), independently of exercise. Cardiac HSP72 accumulation was higher in exercised than in sedentary animals (P < 0.05, 677.16 ± 129.14 vs 246.24 ± 46.30 relative unit, respectively), independently of nandrolone, but not different between nandrolone-treated and untreated animals (P > 0.05, 560.88 ± 127.53 vs 362.52 ± 95.97 relative unit, respectively) independently of exercise. Exercise-induced HSP72 expression was not affected by nandrolone. These levels of HSP72 expression in response to nandrolone administration suggest either a low intracellular stress or a possible less protection to the myocardium.
Resumo:
Sex differences in the development of hypertension and cardiovascular disease have been described in humans and in animal models. In this paper we will review some of our studies which have as their emphasis the examination of the role of sex differences and sex steroids in modulating the central actions of angiotensin II (ANG II) via interactions with free radicals and nitric oxide, generating pathways within brain circumventricular organs and in central sympathomodulatory systems. Our studies indicate that low-dose infusions of ANG II result in hypertension in wild-type male mice but not in intact wild-type females. Furthermore, we have demonstrated that ANG II-induced hypertension in males is blocked by central infusions of the androgen receptor antagonist, flutamide, and by central infusions of the superoxide dismutase mimetic, tempol. We have also found that, in comparison to females, males show greater levels of intracellular reactive oxygen species in circumventricular organ neurons following long-term ANG II infusions. In female mice, ovariectomy, central blockade of estrogen receptors or total knockout of estrogen a receptors augments the pressor effects of ANG II. Finally, in females but not in males, central blockade of nitric oxide synthase increases the pressor effects of ANG II. Taken together, these results suggest that sex differences and estrogen and testosterone play important roles in the development of ANG II-induced hypertension.
Anti-tumor necrosis factor-a for the treatment of steroid-refractory acute graft-versus-host disease
Resumo:
Allogeneic stem cell transplantation has been increasingly performed for a variety of hematologic diseases. Clinically significant acute graft-versus-host disease (GVHD) occurs in 9 to 50% of patients who receive allogeneic grafts, resulting in high morbidity and mortality. There is no standard therapy for patients with acute GVHD who do not respond to steroids. Studies have shown a possible benefit of anti-TNF-a (infliximab)for the treatment of acute GVHD. We report here on the outcomes of 10 recipients of related or unrelated stem cell transplants who received 10 mg/kg infliximab, iv, once weekly for a median of 3.5 doses (range: 1-6) for the treatment of severe acute GVHD and who were not responsive to standard therapy. All patients had acute GVHD grades II to IV (II = 2, III = 3, IV = 5). Overall, 9 patients responded and 1 patient had progressive disease. Among the responders, 3 had complete responses and 6 partial responses. All patients with cutaneous or gastrointestinal involvement responded, while only 2 of 6 patients with liver disease showed any response. None of the 10 patients had any kind of immediate toxicity. Four patients died, all of them with sepsis. Six patients are still alive after a median follow-up time of 544 days (92-600) after transplantation. Considering the severity of the cases and the bad prognosis associated with advanced acute GVHD, we find our results encouraging. Anti-TNF-a seems to be a useful agent for the treatment of acute GVHD.
Resumo:
The purpose of the present study was to explore changes in rat colon motility, and determine the roles of calcium and inositol (1,4,5)-triphosphate (IP3) in colon dysmotility induced by multiple organ dysfunction syndrome (MODS) caused by bacteria peritonitis. The number of stools, the contractility of the muscle strips and the length of smooth muscle cells (SMC) in the colon, the concentration of calcium and IP3 in SMC, and serum nitric oxide were measured. Number of stools, fecal weight, IP3 concentration in SMC and serum nitric oxide concentration were 0.77 ± 0.52 pellets, 2.51 ± 0.39 g, 4.14 ± 2.07 pmol/tube, and 113.95 ± 37.89 µmol/L, respectively, for the MODS group (N = 11) vs 1.54 ± 0.64 pellets, 4.32 ± 0.57 g, 8.19 ± 3.11 pmol/tube, and 37.42 ± 19.56 µmol/L for the control group (N = 20; P < 0.05). After treatment with 0.1 mM acetylcholine and 0.1 M potassium chloride, the maximum contraction stress of smooth muscle strips, the length of SMC and the changes of calcium concentration were 593 ± 81 and 458 ± 69 g/cm³, 48.1 ± 11.8 and 69.2 ± 15.7 µM, 250 ± 70 and 167 ± 48%, respectively, for the control group vs 321 ± 53 and 284 ± 56 g/cm³, 65.1 ± 18.5 and 87.2 ± 23.7 µM, 127 ± 35 and 112 ± 35% for the MODS group (P < 0.05). Thus, colon contractility was decreased in MODS, a result possibly related to reduced calcium concentration and IP3 in SMC.
Resumo:
The mammalian testis serves two main functions: production of spermatozoa and synthesis of steroids; among them estrogens are the end products obtained from the irreversible transformation of androgens by a microsomal enzymatic complex named aromatase. The aromatase is encoded by a single gene (cyp19) in humans which contains 18 exons, 9 of them being translated. In rats, the aromatase activity is mainly located in Sertoli cells of immature rats and then in Leydig cells of adult rats. We have demonstrated that germ cells represent an important source of estrogens: the amount of P450arom transcript is 3-fold higher in pachytene spermatocytes compared to gonocytes or round spermatids; conversely, aromatase activity is more intense in haploid cells. Male germ cells of mice, bank voles, bears, and monkeys express aromatase. In humans, we have shown the presence of a biologically active aromatase and of estrogen receptors (alpha and ß) in ejaculated spermatozoa and in immature germ cells in addition to Leydig cells. Moreover, we have demonstrated that the amount of P450arom transcripts is 30% lower in immotile than in motile spermatozoa. Alterations of spermatogenesis in terms of number and motility of spermatozoa have been described in men genetically deficient in aromatase. These last observations, together with our data showing a significant decrease of aromatase in immotile spermatozoa, suggest that aromatase could be involved in the acquisition of sperm motility. Thus, taking into account the widespread localization of aromatase and estrogen receptors in testicular cells, it is obvious that, besides gonadotrophins and androgens, estrogens produced locally should be considered to be physiologically relevant hormones involved in the regulation of spermatogenesis and spermiogenesis.
Resumo:
Water geochemistry is a very important tool for studying the water quality in a given area. Geology and climate are the major natural factors controlling the chemistry of most natural waters. Anthropogenic impacts are the secondary sources of contamination in natural waters. This study presents the first integrative approach to the geochemistry and water quality of surface waters and Lake Qarun in the Fayoum catchment, Egypt. Moreover, geochemical modeling of Lake Qarun was firstly presented. The Nile River is the main source of water to the Fayoum watershed. To investigate the quality and geochemistry of this water, water samples from irrigation canals, drains and Lake Qarun were collected during the period 2010‒2013 from the whole Fayoum drainage basin to address the major processes and factors governing the evolution of water chemistry in the investigation area. About 34 physicochemical quality parameters, including major ions, oxygen isotopes, trace elements, nutrients and microbiological parameters were investigated in the water samples. Multivariable statistical analysis was used to interpret the interrelationship between the different studied parameters. Geochemical modeling of Lake Qarun was carried out using Hardie and Eugster’s evolutionary model and a model simulated by PHREEQC software. The crystallization sequence during evaporation of Lake Qarun brine was also studied using a Jänecke phase diagram involving the system Na‒K‒Mg‒ Cl‒SO4‒H2O. The results show that the chemistry of surface water in the Fayoum catchment evolves from Ca- Mg-HCO3 at the head waters to Ca‒Mg‒Cl‒SO4 and eventually to Na‒Cl downstream and at Lake Qarun. The main processes behind the high levels of Na, SO4 and Cl in downstream waters and in Lake Qarun are dissolution of evaporites from Fayoum soils followed by evapoconcentration. This was confirmed by binary plots between the different ions, Piper plot, Gibb’s plot and δ18O results. The modeled data proved that Lake Qarun brine evolves from drainage waters via an evaporation‒crystallization process. Through the precipitation of calcite and gypsum, the solution should reach the final composition "Na–Mg–SO4–Cl". As simulated by PHREEQC, further evaporation of lake brine can drive halite to precipitate in the final stages of evaporation. Significantly, the crystallization sequence during evaporation of the lake brine at the concentration ponds of the Egyptian Salts and Minerals Company (EMISAL) reflected the findings from both Hardie and Eugster’s evolutionary model and the PHREEQC simulated model. After crystallization of halite at the EMISAL ponds, the crystallization sequence during evaporation of the residual brine (bittern) was investigated using a Jänecke phase diagram at 35 °C. This diagram was more useful than PHREEQC for predicting the evaporation path especially in the case of this highly concentrated brine (bittern). The predicted crystallization path using a Jänecke phase diagram at 35 °C showed that halite, hexahydrite, kainite and kieserite should appear during bittern evaporation. Yet the actual crystallized mineral salts were only halite and hexahydrite. The absence of kainite was due to its metastability while the absence of kieserite was due to opposed relative humidity. The presence of a specific MgSO4.nH2O phase in ancient evaporite deposits can be used as a paleoclimatic indicator. Evaluation of surface water quality for agricultural purposes shows that some irrigation waters and all drainage waters have high salinities and therefore cannot be used for irrigation. Waters from irrigation canals used as a drinking water supply show higher concentrations of Al and suffer from high levels of total coliform (TC), fecal coliform (FC) and fecal streptococcus (FS). These waters cannot be used for drinking or agricultural purposes without treatment, because of their high health risk. Therefore it is crucial that environmental protection agencies and the media increase public awareness of this issue, especially in rural areas.
Resumo:
The cytotoxicity of the dichloromethane crude extract (DCE), obtained from the aerial parts of Pothomorphe umbellata (L.) Miq (Piperaceae), was evaluated against nine human cancer cell lines (MCF-7, NCI-ADR/RES, OVCAR-3, PC-3, HT-29, NCI-H460, 786-O, UACC-62, K-562). The DCE presented antiproliferative activity with good potency against all cell lines at low concentrations (between 4.0 and 9.5 µg/mL) and with selectivity (1.55 µg/mL) for the leukemia cell line (K-652). DCE (100, 200, 300 and 400 mg/kg, ip) was also evaluated in the Ehrlich ascites tumor model. Both the survival number and the life span of the animals that died increased by at least 45 and 50%, respectively (8 animals per group), demonstrating P. umbellata extract potential anticancer activity. The results of the in vivo antitumor activity prompted the fractionation of the crude extract. The crude extract was submitted to dry column chromatography with dichloromethane-methanol (99:1). The column effluent fractions were extracted with methanol, dried under vacuum yielding fractions FR1 (less polar), FR2 (medium polarity), and FR3 (polar), which were analyzed for their growth inhibition or cytotoxic properties by a 48-h sulforhodamine B cell viability assay by measuring the total protein content. FR1 demonstrated high potency and cytotoxicity, a result compatible with the high toxicity of oxalic acid; FR2, containing 4-nerolidylcathecol, presented the lowest cytotoxic activity compared to the other two fractions but with selectivity for prostate cancer cell line; FR3, containing a mixture of steroids described in the literature as possessing various biological activities, also presented potent anticancer in vitro activity. These results suggest that P. umbellata DCE in vivo antitumor activity may be a consequence of the activity of different active principles.
Resumo:
Disturbed sleep is common in chronic obstructive pulmonary disease (COPD). Conventional hypnotics worsen nocturnal hypoxemia and, in severe cases, can lead to respiratory failure. Exogenous melatonin has somnogenic properties in normal subjects and can improve sleep in several clinical conditions. This randomized, double-blind, placebo-controlled study was carried out to determine the effects of melatonin on sleep in COPD. Thirty consecutive patients with moderate to very severe COPD were initially recruited for the study. None of the participants had a history of disease exacerbation 4 weeks prior to the study, obstructive sleep apnea, mental disorders, current use of oral steroids, methylxanthines or hypnotic-sedative medication, nocturnal oxygen therapy, and shift work. Patients received 3 mg melatonin (N = 12) or placebo (N = 13), orally in a single dose, 1 h before bedtime for 21 consecutive days. Sleep quality was assessed by the Pittsburgh Sleep Quality Index (PSQI) and daytime sleepiness was measured by the Epworth Sleepiness Scale. Pulmonary function and functional exercise level were assessed by spirometry and the 6-min walk test, respectively. Twenty-five patients completed the study protocol and were included in the final analysis. Melatonin treatment significantly improved global PSQI scores (P = 0.012), particularly sleep latency (P = 0.008) and sleep duration (P = 0.046). No differences in daytime sleepiness, lung function and functional exercise level were observed. We conclude that melatonin can improve sleep in COPD. Further long-term studies involving larger number of patients are needed before melatonin can be safely recommended for the management of sleep disturbances in these patients.
Resumo:
Acute gastroenteritis caused by viruses is one of the leading causes of infantile morbidity. The aim of the present study was to investigate the presence of human caliciviruses of the genera norovirus and sapovirus in children up to 3 years of age with acute gastroenteritis from low-income communities in the city of Salvador, Brazil. This study is an extension of previous work carried out to establish the profile of the most prevalent enteric pathogens present in these communities. In this report, 139 fecal samples, collected from July 2001 to January 2002 were analyzed by RT-PCR and 13 (9%) were positive for human caliciviruses. By sequencing, seven isolates were characterized as norovirus genogroup GII and one as sapovirus genotype GII/1. Sequencing of the previously detected group-A rotaviruses and human astroviruses was also performed and revealed the circulation of rotavirus group A genotypes G1P[8] and G9P[8], and human astrovirus genotypes 6, 7, and 8. No mixed infection was observed. Community-based studies provide geographically representative information on disease burden. However, there are only a few reports in developing countries concerning the genotypes of the most important gastroenteric viruses detected in such communities. The present findings demonstrate the wide diversity of genotypes of the most important viruses responsible for acute gastroenteritis circulating in low-income communities.
Resumo:
We evaluated the effects of vincristine on the gastrointestinal (GI) motility of awake rats and correlated them with the course of vincristine-induced peripheral neuropathy. Vincristine or saline was injected into the tail vein of male Wistar rats (180-250 g) on alternate days: 50 µg/kg (5 doses, N = 10), 100 µg/kg (2, 3, 4 and 5 doses, N = 49) or 150 µg/kg (1, 2, or 5 doses, N = 37). Weight and stool output were measured daily for each animal. One day after completing the vincristine treatment, the animals were fasted for 24 h, gavage-fed with a test meal and sacrificed 10 min later to measure gastric emptying (GE), GI transit and colon weight. Sensory peripheral neuropathy was evaluated by hot plate testing. Chronic vincristine treatments with total cumulative doses of at least 250 µg/kg significantly decreased GE by 31-59% and GI transit by 55-93%. The effect of 5 doses of vincristine (150 µg/kg) on GE did not persist for more than 1 week. Colon weight increased after 2 and 5 doses of vincristine (150 µg/kg). Fecal output decreased up to 48 h after the fifth dose of vincristine (150 µg/kg). Vincristine decreased the heat pain threshold 1 day after 5 doses of 50-100 µg/kg or after 3-5 doses of 150 µg/kg. This effect lasted for at least 2 weeks after the fifth dose. Chronic intravenous vincristine treatment delayed GE and GI transit of liquid. This effect correlated with the peak increase in colon weight but not with the pain threshold changes.
Resumo:
The objective of this study was to investigate the occurrence of vancomycin-resistant Enterococcus (VRE) cross-transmission between two patient groups (long-term dialysis and kidney transplant patients). Molecular typing, by automated ribotyping with the RiboPrinter Microbial Characterization System (Qualicon, USA), was used to analyze VRE isolates from 31 fecal samples of 320 dialysis patients and 38 fecal samples of 280 kidney transplant patients. Clonal spread of E. faecalis and E. casseliflavus was observed intragroup, but not between the two groups of patients. In turn, transmission of E. gallinarum and E. faecium between the groups was suggested by the finding of vancomycin-resistant isolates belonging to the same ribogroup in both dialysis and transplant patients. The fact that these patients were colonized by VRE from the same ribogroup in the same health care facility provides evidence for cross-transmission and supports the adoption of stringent infection control measures to prevent dissemination of these bacteria.