Expression of inducible nitric oxide synthase in the liver of bile duct-ligated Wistar rats with modulation by lymphomononuclear cells

BACKGROUND: The current study evaluated whether biliary tract obstruction stimulates inducible nitric oxide synthase (iNOS) protein expression in the liver and analyzed the implication of lymphomononuclear cells and interleukin-4 (IL-4). METHODS: Male Wistar rats were used. Bile flow interruption was achieved by a complete division of the extrapancreatic common bile duct. iNOS expression was determined by both the Western blot technique and immunohistochemistry. RESULTS: iNOS protein was markedly expressed in the liver 7 days after bile duct obstruction. Treatment with thymostimulin (TP-1), a partially purified thymic extract, reduced the intensity of the expression of iNOS protein in the liver after bile duct ligation. Recent data have suggested that IL-4 attenuates iNOS protein expression. We then analyzed the involvement of this anti-inflammatory cytokine on the modulation of iNOS expression in the liver. The liver from rats that underwent bile duct ligation (BDL) showed a lower content of IL-4 than that of sham-operated (SO) rats. TP-1 treatment increased the content of IL-4 in the liver. Liver slices incubated in vitro with Escherichia coli lipopolysaccharide (LPS, 10 microg/mL) stimulated the expression of iNOS protein. The level of LPS-induced iNOS expression was reduced by lymphomononuclear cells obtained from sham-operated animals. However, lymphomononuclear cells isolated from BDL rats potentiated the induction of iNOS expression by LPS-stimulated liver. However, lymphomononuclear cells from TP-1-treated BDL rats failed to modify LPS-stimulated iNOS expression. The different effect of lymphomononuclear cells on the modulation of iNOS expression in the liver was associated with their ability to generate IL-4. CONCLUSIONS: The liver of jaundiced rats markedly expressed iNOS protein, which was associated to modifications in the content of IL-4 in the liver. Furthermore, lymphomononuclear cells modulate iNOS protein expression in the liver by a mechanism in which IL-4 is involved.     

Bone mass and mineral metabolism in liver transplant patients treated with FK506 or cyclosporine A

The purpose of this study was to compare the effects of Cyclosporine A (CyA) and FK506 on bone mass and mineral metabolism in liver transplantation (LT) patients. A prospective study was performed on 18 male patients who underwent LT treated with CyA, and 7 LT patients who received FK506. Bone mineral density (BMD) of the lumbar spine and proximal femur (DPX-L) was measured before and at 6, 12, and 24 months after transplantation. Moreover, intact parathyroid hormone (PTH) and 25-hydroxyvitamin D (25OHD) levels were determined at the same time. The cumulative dose of glucocorticoids was calculated in all patients. At 6 months, lumbar BMD decreased 5.2 ± 1.2 % (P=0.0005) and 2.9 ± 2.1 % (p=ns) in CyA and FK506 groups, respectively. Lumbar BMD reached baseline values at 1 year in the FK506 group and 2 years after LT in the CyA group. Moreover, significant intergroup differences in femoral neck BMD changes after 2 years of transplant were observed (CyA: −5.2 ± 1.97 versus FK506: +1.55 ± 2.2 %;P=0.039). In the first year posttransplant both groups showed a marked increase in PTH and 25OHD levels. The mean cumulative dose of glucocorticoids was higher in the CyA group (CyA group 11.06 ± 0.46 g versus FK 506 group 6.71 ± 0.42 g;P<0.001), and multiple linear regression analysis showed a negative correlation between BMD changes at the lumbar spine and mean cumulative dose of glucocorticoids (P=0.022). In conclusion, our data suggest that after liver transplantation treatment with FK506 shows a more favorable long-term effect on bone mass evolution than CyA therapy. These differences seem to be associated with the lower dose of glucocorticoids used in the FK506 group.     

The effects of learning through discussion in a course in occupational therapy: a search for deep learning

This preliminary educational research study examined occupational therapy students' perceptions of the learning through discussion (LTD) method. The study incorporated both quantitative and qualitative strategies. A convenience sample of nine post-professional occupational therapy doctoral students participated. Overall, participating students reported positive experiences when engaging in LTD, reporting that they had actively engaged in critical thinking and learning and experienced transformative learning. However, the results of nonparametric analysis revealed no significant change in the perceptions of the students of their classroom performances. Findings are discussed in light of current educational programs in occupational therapy. Future research studies are recommended to further examine the efficacy of LTD and explore its utility for training allied health professionals.     

P300 amplitude as a possible correlate of frontal degeneration in schizophrenia

The existence of neurodegeneration is a debated issue in schizophrenia research. The P300 component of event-related electrical potentials (ERP) has been related to the different degree of damage to gray and white matter. This study explores the possible relationship between P300 amplitude and/or latency and the existence of degenerative processes in schizophrenia, by assessing its correlation with volume of sulcal CSF and duration of illness, as transversal indicators of neurodegeneration. Nineteen patients (14 males, 5 females) and 13 controls (6 males, 7 females) were studied with MRI and electrophysiological records (P300). The possible influence of sex and age at the time of the exploration was statistically controlled in both groups. The results show a significant negative correlation between P300 amplitude and prefrontal CSF volume in the patient group. A lower though still significant correlation was also found between P300 amplitude and duration of illness, whereas no correlation was found in the control group. These results support the hypothesis that P300 amplitude may be interpreted as a marker of neurodegeneration in schizophrenia.     

Melatonin versus vitamin E as protective treatment against oxidative stress after extra-hepatic bile duct ligation in rats

The aims of the present study were first to compare the effects of melatonin and vitamin E on the cholestasis syndrome and their protective effect on liver injury, and second, to evaluate the activity of antioxidant enzymes after treatment with these antioxidant drugs. Cholestasis was achieved in adult male Wistar rats by double ligature and section of the extra-hepatic biliary duct. Hepatic and plasma oxidative stress markers were evaluated by changes in the amount of lipid peroxides, measured as malondialdehyde (MDA) and reduced glutathione (GSH) in plasma and homogenates of hepatic tissue. Serum bilirubin, alkaline phosphatase (AP), and gamma-glutamyl-transpeptidase (GGT) were used to evaluate the severity of cholestasis, and serum levels of alanine aminotransferase (ALT) and aspartate aminotransferase (AST) were used to evaluate the hepatic injury. Both vitamin E and melatonin were administrated 1 day before and 7 days after bile duct ligation. Acute ligation of the bile duct was accompanied by a significant increased in MDA and a decrease in GSH levels in both plasma and liver, as well as a significant reduction in antioxidant enzymes activities. The overall analysis of both treatments showed that melatonin (500 microg/kg daily) offered significantly better protection against cholestasis and a superior protective effect on hepatic injury than did vitamin E (15 mg/kg daily). Although vitamin E treatment resulted in a reduction of parameters of oxidative stress, the results were significantly better after a much lower daily dose of melatonin. Moreover, melatonin treatment was associated with a significant recovery of antioxidative enzymes. In conclusion, the present paper demonstrates a correlation between the intensity of biliary tract obstruction and increased free radical generation, as well as a direct correlation between the level of oxidative stress and the biochemical markers of liver injury. Melatonin (at a much lower dose than vitamin E) was much more efficient than vitamin E in reducing the negative parameters of cholestasis, the degree of oxidative stress and provided a significantly greater hepatoprotective effect against the liver injury secondary to the acute ligation of the biliary duct.     

Association of thyroid hemiagenesis and Graves disease

Thyroid hemiagenesis is a very infrequent abnormality. We present a case of Graves disease associated to a congenital hemiagenesis of the thyroid gland. The thyroid scintigraphy, ultrasonography and laboratory analysis (that showed the existence of thyroid hyperfunction and the present of thyroid stimulating antibodies) were decisive in the diagnosis.     

Use of narrow-band spectrogram in voice surgery

Subjective voice qualities are difficult to transform into permanent objective visual patterns. Voice spectrography is not a new method of voice analysis. However, in spite of many contributions to the literature, few otolaryngologists have used this interesting method as a clinical tool for evaluating the voice before and after surgical voice procedures. We used the Yanagihara method for classifying degrees of hoarseness, witch is based on the appearance of noise components and loss of harmonic components as the major acoustic factors related to hoarseness. This classification is clinically useful because the severity of hoarseness can be numerically expressed. Changes in the harmonic components were analyzed by voice spectrographic analysis.     

Dysphagia caused by Zenker's diverticulum after total laryngectomy

Zenker's diverticulum is a mucosal lined outpouching of pharynx through Lainert's space that causes dysphagia of the upper digestive tract. Multiples theories try to explain the acquired etiology of this entity, attributing its origin to a disfunction of pharynx-esophageal sphincter. A case of total larynguectomy with hypopharyngeal diverticulum and progressive dysphagia to solid food is presented. We analyze the etiopathogenic mechanisms and the definitive characteristics of this entity. We review mundial literature, being exceptional the fact of finding clinical manifestations in diverticulum of larynguectomized patients.