Coagulation factor V and VIII/V ratio as predictors of outcome in paracetamol induced fulminant hepatic failure: relation to other prognostic indicators

The value of coagulation factor V and VIII/V levels as prognostic indicators was assessed in 27 patients with fulminant hepatic failure and compared with other predictive indices. Admission factor V levels were significantly reduced in 22 patients with paracetamol induced hepatic failure compared with a healthy control group (median 9.5% v 103%, respectively; p less than 0.001) and with lower values in non-A non-B hepatitis (median 2.7%). Values in the seven patients who died after paracetamol overdose, considered together with the four who underwent liver transplantation (group median 5.1%), were significantly lower than in the 11 who survived (median 11.8%; p less than 0.01). Median admission factor VIII was higher in those who died or received a transplant than in those who survived (298% v 162%; p less than 0.05), with both results higher than in healthy volunteers (median 104%; p less than 0.01) but lower than in non-A non-B hepatitis (median 340%). The ratio of factor VIII/V on admission was less than 30 in all patients who survived paracetamol overdose (median 17) with corresponding values greater than 30 in 10 of 11 of those who died (median 39). A factor V result less than or equal to 10% on admission predicted an adverse outcome in 10 of 11 fatal cases, a 91% sensitivity which was greater than for the previously defined indicator of an arterial blood pH less than 7.30 on admission (sensitivity 82%). Prothrombin time at admission or on day 4 did not usefully predict outcome in our series. Predictive accuracy was 73% and 82% for factor V and admission acidosis respectively and 95% for factor V in conjunction with admission coma grade III or IV and factor VIII (ratio > 30). These criteria may be useful in selecting patients with paracetamol induced fulminant hepatic failure for transplantation.

Facial exercise therapy for facial palsy: systematic review and meta-analysis

The effectiveness of facial exercises therapy for facial palsy has been debated in systematic reviews but its effects are still not totally explained.

OBJECTIVE

To perform a systematic review with meta-analysis to evaluate the effects of facial exercise therapy for facial palsy.

DATA SOURCES

A search was performed in the following databases: Cochrane Controlled Trials Register Library, Cochrane Disease Group Trials Register, MEDLINE, EMBASE, LILACS, PEDro, Scielo and DARE from 1966 to 2010; the following keywords were used: 'idiopathic facial palsy', 'facial paralysis', 'Bell's palsy', 'physical therapy', 'exercise movement techniques', 'facial exercises', 'mime therapy' 'facial expression', 'massage' and 'randomized controlled trials'.

REVIEW METHODS

The inclusion criteria were studies with facial exercises, associated or not with mirror biofeedback, to treat facial palsy.

RESULTS

One hundred and thirty-two studies were found but only six met the inclusion criteria. All the studies were evaluated by two independent reviewers, following the recommendations of Cochrane Collaboration Handbook for assessment of risk of bias (kappa coefficient = 0.8). Only one study presented sufficient data to perform the meta-analysis, and significant improvements in functionality was found for the experimental group (standardized mean difference (SMD) = 13.90; 95% confidence interval (CI) 4.31, 23.49; P = 0.005).

CONCLUSION

Facial exercise therapy is effective for facial palsy for the outcome functionality.

Hepatic and extrahepatic hepatitis C virus replication in relation to response to interferon therapy

Response to a 1-yr course of interferon-alpha 2b was assessed in 18 patients with chronic hepatitis C virus infection in relation to clinical, biochemical and histological parameters and to the presence or absence of hepatitis C virus RNA and the presumed replicative form of the virus (negative-strand hepatitis C virus RNA) in serum, liver and peripheral blood mononuclear cells. The findings were compared with those in seven untreated patients studied over the same period. At the start of the study, positive-strand hepatitis C virus RNA was found in sera of all 25 patients, in livers of 24 and in peripheral-blood mononuclear cells of 19 of 22 tested; negative strand was found in livers of 11 and in peripheral-blood mononuclear cells of 15 of 22. Negative-strand hepatitis C virus RNA was not found in the serum of any patient at any stage. All of the five treated patients considered to show complete response during the study period cleared hepatic hepatitis C virus RNA, and four also became seronegative, but three had evidence suggestive of viral replication in their peripheral-blood mononuclear cells; two of these last patients subsequently relapsed. Loss of hepatic hepatitis C virus RNA was the only significant difference between these five and the seven partial and six nonresponders, but it is uncertain whether the observed changes were due specifically to interferon-induced modulation of virus expression because similar (apparently spontaneous) changes were seen in four of the untreated patients.(ABSTRACT TRUNCATED AT 250 WORDS)

Erythropoietin pharmacokinetics in premature infants: developmental, nonlinearity, and treatment effects

Erythropoietin (EPO) pharmacokinetic studies were performed in premature infants (birth weight < 1.25 kg) and normal adults. Infants were divided into two subgroups on the basis of whether they received chronic treatment with recombinant human EPO (rhEPO; 500 IU.kg-1.wk-1 for 6 wk) beginning at 2-4 wk of life. Ten adults and seven rhEPO-treated infants underwent intravenous pharmacokinetic studies at escalating rhEPO doses: 10, 100, and 500 IU/kg. To test for pharmacokinetic developmental and treatment effects, an equal number of non-EPO- and EPO-treated infants were studied with 100 IU/kg on the last day of treatment. Compared with adults, very low birth weight infants demonstrated significantly greater plasma clearance and distribution volume and significantly shorter fractional elimination times (FET) and mean residence time (MRT) at all three rhEPO doses. Both infants and adults demonstrated nonlinear EPO elimination, i.e., increasing rhEPO dosing was associated with decreasing plasma clearance and increasing FET and MRT. In the absence of rhEPO treatment there were no pharmacokinetic differences between the two subgroups of infants studied 6 wk apart. In contrast, the rhEPO-treated infant subgroup demonstrated a significant increase in clearance and a decrease in FET and MRT following 6 wk of treatment. Enhancement of rhEPO efficacy in the prevention and treatment of anemia in premature infants may require higher doses administered in a progressively increasing fashion.

Kinetic evaluation of nonlinear drug elimination by a disposition decomposition analysis. Application to the analysis of the nonlinear elimination kinetics of erythropoietin in adult humans

The disposition-decomposition analysis (DDA) methodology enables isolation of the overall elimination and distribution effects in pharmacokinetics and facilitates analysis which focuses on drug elimination kinetics and does not require a specific structured modeling of drug distribution processes. A computer algorithm enables a curve fitting and a kinetic estimation by integration of the convolution type integrodifferential equation in the DDA. The approach is demonstrated in an analysis of the nonlinear disposition kinetics of erythropoietin (Epo) in 10 healthy, adult human subjects who each received 10, 100, and 500 U/kg i.v. bolus doses of Epo. The nonlinearity is analyzed according to a Michaelis-Menten type nonlinear elimination function, considering simultaneous fitting to the data from all three doses in each subject. The simultaneous fittings produced estimates of the Michaelis-Menten parameters (mean, % cv) Vm (901 mU/mL/h, 19.4%) and km (4814 mU/mL, 24.6%). A linear clearance parameter is defined as the asymptotic clearance value approached when the drug level decreases toward zero. The degree of nonlinearity reached from various dosings was quantified in terms of a clearance ratio which is defined as the ratio between the linear clearance and the clearance estimated for the maximum drug concentration encountered at the given dose level. The subjects showed very little nonlinearity at the 10 U/kg dosing with a mean clearance ratio of 1.07 (2.1% CV) A statistically significant increase in the degree of nonlinearity was observed in the Epo elimination kinetics as the dosing level was increased to 100 and 500 U/kg, reaching clearance ratios of 1.66 (14% CV) and 4.33 (27% CV), respectively. A zero value for the global elimination rate parameter in all 30 dosings indicates that Epo's elimination is entirely accounted for by nonlinear pathway(s).

Simple method for determination of paraquat in plasma and serum of human patients by high-performance liquid chromatography

A simple and fast HPLC system is presented for quantifying paraquat in human plasma and serum using 1,1'-diethyl-4,4'-bipyridyldiylium (diethyl paraquat) as an internal standard. An octadecyl-silica column is used with an eluent of 10% acetonitrile (v/v) containing sodium 1-octanesulphonic acid (3.0 mM) and a diethylamine-orthophosphoric acid buffer (pH 3). Unlike with other techniques, sample treatment requires only the precipitation of protein contents by 6% perchloric acid (v/v) in methanol. The method has a limit of detection of 0.1 microg/ml and is linear up to 10 microg/ml. The serum of four patients and the plasma of one patient with paraquat intoxication's were analysed and positive identification and quantification was readily achieved. One of those patients survived, partially given the rapid disclosure of his levels of paraquat. Therefore, this method is suitable for quantification of paraquat in toxicological samples. It may be used as a prognostic tool in critical case detoxification and to quickly identify potentially salvageable patients for enrollment in new hemofiltration studies.

A comparison of nonlinear pharmacokinetics of erythropoietin in sheep and humans

The primary mechanism of erythropoietin's (EPO) in vivo elimination and the tissue, or tissues, responsible are unknown. Previous studies indicating that EPO pharmacokinetic (PK) behaviour is nonlinear suggest that EPO elimination takes place by a saturable mechanism. A versatile PK system analysis, the Disposition Decomposition Analysis (DDA), capable of quantification of the Michaelis-Menten parameters, V(m) and k(m) was used to analyze and compare EPO's PK behaviour in newborn sheep and preterm infants. Lambs and infants both demonstrated nonlinear PK behaviour appropriately analyzed with DDA. Compared to preterm infants, lambs had significantly greater (p<0.05) elimination capacity as determined by the V(m) (2789+/-525 versus 1767+/-250 mU/mL per h (mean+/-S.E.), respectively), and larger extrapolated linear clearances (116+/-19.1 versus 21.3+/-1.75 mL/kg per h, respectively) (p<0.01). Lambs also demonstrated significantly larger (p<0.01) degrees of nonlinearity as judged by smaller mean k(m) values (2142+/-258 versus 6796+/-1.007 mU/mL, respectively). Of note, although the DDA does not distinguish what the mechanism of EPO elimination is, enzymatic degradation and receptor-mediated cellular internalization are two possibilities. The in vivo DDA-derived k(m) values were similar to reported in vitro binding affinity k(d) data for erythroid progenitors and cell lines having EPO-R's, i.e. 240-2400 mU/mL. The present study's demonstration that EPO's nonlinear PK behaviour in both sheep and humans can be analyzed by the DDA methodology indicates that the sheep model may be used in invasive studies needed to further characterize the mechanism of EPO elimination.

Effects of ribavirin on intrahepatic and extrahepatic expression of hepatitis C virus in interferon nonresponsive patients

Response to ribavirin therapy (1,000-1,200 mg/day for 6 months) was evaluated in nine patients with chronic hepatitis C virus (HCV) infections who had previously failed to respond to a 6-month course of alpha-interferon. All had chronic active hepatitis with elevated serum aminotransferase activities (mean +/- SD = 138 +/- 66IU/I). During ribavirin therapy, three showed a complete response (normalized serum aminotransferase), although in one patient this returned to the pretreatment level 2 months after treatment was stopped. Three others showed a partial response (serum aminotransferase reduction by > or = 50%) and the remainder showed no response. There were no consistent changes in HCV-RNA (positive strand) in serum, liver, or peripheral blood mononuclear cells during therapy, but two patients lost HCV-RNA from serum and three of five patients with negative strand HCV-RNA in their livers lost this putative replicative form of the virus. The findings suggest that ribavirin may exert its effects by suppressing viral replication rather than by eradicating the virus, at least in this group of patients, and that the drug may have some benefit in selected cases of chronic hepatitis C that are resistant to interferon. However, peripheral blood mononuclear cells represent a major extrahepatic reservoir of HCV and the present regimen of ribavirin therapy did not significantly affect this situation. More prolonged therapy may be required to eradicate the virus from this large pool of cells with the potential to continually reinfect the liver.

Hepatitis C virus infection in Schistosomiasis mansoni in Brazil

The involvement of the hepatitis C virus (HCV) in the severity of liver disease in chronic schistosomiasis was investigated in 215 Brazilian patients with S. mansoni infections, but without evidence of hepatitis B surface antigen (HBsAg). Forty-three had hepatointestinal (HIS) and 172 had hepatosplenic schistosomiasis (HSS), and 135 had compensated (HSSC), and 37 had decompensated (HSSD) liver disease. Fifty-two (24%) were found to have evidence of HCV infection (seropositive for anti-HCV antibodies and/or HCV-RNA). These comprised 35 (95%) of the 37 with HSSD, 16 (12%) of the 135 with HSSC, and 1 (2.4%) of the 43 with HIS, compared with only 1 (2%) of 50 control patients without S. mansoni. Testing of matched liver tissue and peripheral blood mononuclear cells (PBMCs) from 25 patients (6 HSSC and 19 HSSD) with HCV infections showed that 17 (68%) had "active" viral infections, in that negative strand HCV-RNA (the presumed replicative intermediate of the virus) could be detected in liver and/or PBMCs. Among these 25, negative strand HCV-RNA was found in 16 (84%) of the 19 with chronic active hepatitis, but in only 1 (17%) of the 6 with mild or inactive disease (P < 0.01). HCV-RNA was detected in matched spleen specimens from 9 of 10 patients (all of whom were also positive in PBMCs), suggesting that the spleen is an important extrahepatic reservoir of the virus.(ABSTRACT TRUNCATED AT 250 WORDS)

Systemic and hepatic hemodynamics in hepatosplenic Manson's schistosomiasis with and without propranolol

Systemic and hepatic hemodynamics were prospectively studied in 11 patients with Manson's schistosomiasis and portal hypertension, as well as alterations resulting from the use of propranolol. It was decided that patients whose portal pressure was reduced by 30% with the use of the drug would not undergo surgery and that treatment would consist of the chronic use of propranolol, associated with sclerosis of esophageal varices. This objective was not met by any of the patients whose portal pressure was measured and the study was interrupted. Results show that patients with Manson's schistosomiasis and portal hypertension have hyperdynamic circulation, mild pulmonary hypertension, greatly increased splenic blood flow, and preservation of total hepatic blood flow. Administration of propranolol corrects hyperdynamic circulation, aggravates pulmonary hypertension, does not alter portal pressure and reduces the sectorial portal blood flows, especially of the azygos vein, with maintenance of total hepatic blood flow. These data favor the hypothesis of portal overflow in the physiopathology of portal hypertension of schistosomiasis.

Hepatitis B virus infection in schistosomiasis mansoni

Schistosomiasis and hepatitis B virus (HBV) infection are very common in Brazil but the interrelationships between the two infections are poorly understood. We have undertaken a detailed serological study of the prevalence of HBV markers in 189 Brazilian patients with chronic schistosomiasis mansoni, 46 with hepatointestinal (HIS) and 143 with hepatosplenic (HSS) schistosomiasis, 12 of the latter having decompensated liver disease (HSSD), and in 50 control patients. Sera were tested for HBsAg, anti-e, anti-HBc, anti-HBs and HBV-DNA. Eighty-three (44%) of the 189 schistosoma patients had at least one marker of HBV infection, 18 of whom (10%) were seropositive for HBsAg. All the controls were HBsAg negative, but ten (20%) had anti-HBc and anti-HBs. There was no significant difference in the frequency of these markers between HIS (14/46, 30.4%), HSSC (43/131, 34.5%), and the controls. Among the HBsAg-positive patients, one had HIS (HBV-DNA negative), seven had HSSC (one HBV-DNA positive) and ten had HSSD (six HBV-DNA positive), a significant association of HBV carriage with HSSD (P << 0.001). Mean (+/- SD) ALT values were significantly (P < 0.001) higher in HBsAg-positive HSSD patients (70.7 +/- 18 IU/liter) than in those with HSSC (29.5 +/- 15 IU/liter). Liver biopsies were performed in 12 HBsAg-positive patients (one with HIS, three with HSSC, and eight with HSSD) and in 50 HBsAg-negative HSSC patients. Seven of the eight HSSD patients had chronic active hepatitis with cirrhosis, and one had inactive cirrhosis. All three patients with HSSC and the one with HIS had chronic persistent hepatitis, with periportal fibrosis in three.(ABSTRACT TRUNCATED AT 250 WORDS)

Use of specific ELISA for the detection of antibodies directed against p53 protein in patients with hepatocellular carcinoma

AIMS

To analyse the significance of antibodies to p53 protein as a serological marker for changes in p53 gene expression in patients with hepatocellular carcinoma.

METHODS

Thirty eight patients with hepatocellular carcinoma, 19 showing accumulation of p53 protein by immunohistochemistry and 19 having no accumulation, were studied. The presence of anti-p53 was tested using a novel ELISA utilising a recombinant p53 protein as a capture system and verified by western blotting. p53 gene mutations were sought by single strand conformational polymorphism and DNA sequencing analyses.

RESULTS

Of 19 patients with p53 protein accumulation in tumour tissue, 10 (52%) had antibodies to p53 in serum by ELISA. Four patients with p53 negative immunohistochemistry also had detectable anti-p53. Western blot analysis confirmed the specificity of the ELISA positive serum samples. The presence of anti-p53 was independent of serum alpha-fetoprotein and was detected in 50% of small tumours while only 8% were alpha-fetoprotein positive. Mutations affecting exons 5 and 6 seem to be more frequently associated with development of anti-p53, than mutations in exons 7 or 8.

CONCLUSIONS

The ELISA for anti-p53 is a convenient and specific tet for the detection of humoral response to alterations in p53 gene expression and could be of value in the diagnosis and characterisation of patients with hepatocellular carcinoma.

Basal transepidermal water loss: right/left forearm difference and motoric dominance

Background/alms: Evaporimetry and transepidermal water loss (TEWL) evaluations are among the most important means of approaching basic cutaneous physiology in terms of its epidermal barrier function. However, physiological skin complexity, together with the loose specifications currently available for analytical purposes, justify the need for further investigating and identifying eventual covariates and limiting factors with respect to both the epidermal barrier function issue and evaporimetry itself.

METHODS

The relevant operating procedures were investigated with respect to the anatomical and functional equivalence of contralateral sites as they are often used in TEWL determinations and topically applied substance efficacy testing. The study was conducted on human volunteers using five different sites in both forearms, using a standard evaporimetry apparatus. Special attention was put on the right/left forearm difference regarding normal daily life motoric dominance reported by each individual.

RESULTS

A consistent difference between TEWL values measured at the most active arm was detected when compared with the readings from the opposite limb. Also, those sites placed nearer the extremities of the forearm behave differently from the inner ones.

CONCLUSIONS

All information thus gathered suggests that using contralateral sites in study protocols for TEWL determinations, particularly when one side is intended to act as control, requires awareness with respect to the physiological and functional differences of the sampling sites chosen. In any case, a proper randomisation and balancing of the experimental design is crucial.

High prevalence of hepatitis C virus in the normal Libyan population

The prevalence of hepatitis C virus (HCV) in Libya has been investigated by seeking evidence of HCV infection in 266 healthy Libyan subjects (147 females, 119 males; age range 1-78 years), 76 of whom were registered blood donors. None had any history of blood transfusions, surgery, homosexuality, drug misuse or other risk factor for viral hepatitis. Sera from all subjects were tested for anti-HCV antibodies by enzyme-linked immunosorbent assay against synthetic structural and non-structural HCV peptides from the HCV core, envelope, NS1, NS3/NS4 and NS5 regions. Eighteen (6.8%), all of whom were seronegative for hepatitis B surface antigen (HBsAg), were found to be anti-HCV positive (including 5 blood donors). The patterns of reactivity against the individual peptides varied between subjects as follows: core (14 subjects), envelope (11), NS1 (9), NS3/NS4 (10), and NS5 (6). Fourteen of the 18 had elevated serum aminotransferase activities (AST/ALT) but so also did 9 other subjects who were seronegative for both HBsAg and anti-HCV. Twelve of the 18 anti-HCV positive subjects, including 3 of the 5 anti-HCV positive blood donors, had circulating HCV RNA detected by the polymerase chain reaction. HCV RNA was also detected in 3 of the 9 anti-HCV negative cases with elevated AST/ALT. The finding that 21 (7.9%) of the 266 subjects had evidence of HCV infection indicates that there is a very high frequency of 'community-acquired' HCV in the normal Libyan population, and this has major implications for blood transfusion in that country.

Ultrasonography of the liver and spleen in Brazilian patients with hepatosplenic schistosomiasis and cirrhosis

Ultrasonography is now widely used in the diagnosis and management of patients with chronic Schistosoma mansoni infections. The present study was undertaken to evaluate the use of ultrasonography in patients with hepatosplenic schistosomiasis (HSS) with and without cirrhosis. Ninety-seven patients (52 males; median age 38 years, range 19-68 years) with HSS, 65 with well compensated (HSSC) and 32 with decompensated (HSSD) disease and cirrhosis, were systematically examined by ultrasound. Hepatic fibrosis was graded according to WHO recommendations. Typical atrophy of the right hepatic lobe accompanied by hypertrophy of the left lobe, with a rounded inferior marginal edge, was seen in 86 (88.7%) patients. Periportal fibrosis was observed in 83 (85.6%) cases and confirmed histologically in all. In 66 patients (68.0%) thickening of the gallbladder wall, associated with periportal fibrosis and extending from the branches of the porta hepatis, was noted. No evidence of biliary disease was found in these patients and gallstones were present in only 3 cases. Fourteen (43.8%) of the HSSD patients could not be classified for grade of fibrosis because of the advanced stage of cirrhosis related to hepatitis B or C viral infection. Of the remaining 18 HSSD patients, none had only grade I fibrosis (vs. 10.8% of HSSC, P = 0.054) and only 6 had grade II (vs. 67.7% of HSSC, P < 0.0005), while the frequency of grade III was significantly higher in the HSSD patients than in those with HSSC (37.5% vs. 21.5%, P = 0.049). These findings indicate that although ultrasonography is a very valid technique for assessing patients with pure HSS, and should be considered the 'gold standard', it is not reliable for assessing periportal fibrosis in patients with concomitant cirrhosis due to other causes.

Evaluation of the vaccination status in pediatric renal transplant recipients

To assess the immunization status of pediatric renal transplant patients followed at a single center in Brazil, vaccination charts of all patients aged between one and 18 yr were analyzed both pre- and post-transplantation. Appropriate immunization was defined according to the National Immunization Program (routine vaccines) - for all Brazilian children - and the Special Immunobiological Agents Program that also includes special vaccines for immunodeficient or other high-risk children. A total of 46 patients was evaluated (mean age 13.7 yr; range 4-17 yr). Vaccination charts were found to be up to date in only two patients (4.3%) pretransplant and in two (4.3%) post-transplant. Although 36 patients (62.2%) in the pretransplant phase and 24 (52.1%) in the post-transplant phase had been vaccinated according to the National Immunization Program, they had not received the special vaccines indicated for their immunocompromised condition. Therefore, despite being followed at a referral center, almost all patients presented an incomplete immunization status pre- and post-transplant. This probably reflects missed opportunities and medical/parental apprehension related to vaccination of patients with chronic renal insufficiency, dialysis or kidney transplantation. Efforts should be made to ensure adequate vaccination in children with kidney diseases, especially before kidney transplantation.

Renal cortical remodelling by NO-synthesis blockers in rats is prevented by angiotensin-converting enzyme inhibitor and calcium channel blocker

The cortical remodelling was studied when chronically nitric oxide synthesis (NOs) blockade (L-NAME-induced) hypertensive rats are simultaneously treated, or not, with angiotensin-converting enzyme inhibitor or calcium channel blocker. Four groups of eight rats each were studied as follows: Control (C), L-NAME (L), L-NAME+Enalapril (L+E) and L-NAME+Verapamil (L+V). The systolic blood pressure (SBP) was weekly recorded. The cortex of the left kidneys was analysed according to the vertical section design. The volume-weighted mean glomerular volume (VWGV) was made through the "point-sampled intercepts" method. Enalapril and verapamil were efficient in reducing the SBP in rats submitted to NOs blockade. Glomeruli had considerable alterations in L group rats (glomerular hypertrophy or sclerosis) and tubular atrophy. The VWGV was 100% greater in L group rats than in the C group rats, while it was 30% smaller in L+E and L+V groups than in L group. The tubular volume was 30-50% greater, while the tubular length was 20-30% smaller in the L group than in the other groups. The renal cortical region showed glomerular sclerosis/hypertrophy and tubular remodelling in rats with NOs blockade that was efficiently prevented with the simultaneous treatment with enalapril or verapamil.

Improvement of adynamic bone disease after renal transplantation

Low bone remodeling and relatively low serum parathyroid hormone (PTH) levels characterize adynamic bone disease (ABD). The impact of renal transplantation (RT) on the course of ABD is unknown. We studied prospectively 13 patients with biopsy-proven ABD after RT. Bone histomorphometry and bone mineral density (BMD) measurements were performed in the 1st and 12th months after RT. Serum PTH, 25-hydroxyvitamin D, 1,25-dihydroxyvitamin D, and osteocalcin were measured regularly throughout the study. Serum PTH levels were slightly elevated at transplantation, normalized at the end of the third month and remained stable thereafter. Bone biopsies performed in the first month after RT revealed low bone turnover in all patients, with positive bone aluminum staining in 5. In the 12th month, second biopsies were performed on 12 patients. Bone histomorphometric dynamic parameters improved in 9 and were completely normalized in 6, whereas no bone mineralization was detected in 3 of these 12 patients. At 12 months post-RT, no bone aluminum was detected in any patient. We also found a decrease in lumbar BMD and an increase in femoral BMD. Patients suffering from ABD, even those with a reduction in PTH levels, may present partial or complete recovery of bone turnover after successful renal transplantation. However, it is not possible to positively identify the mechanisms responsible for the improvement. Identifying these mechanisms should lead to a better understanding of the physiopathology of ABD and to the development of more effective treatments.

Myocardial microcirculation stereological changes in rats subjected to nitric oxide synthesis inhibition

This work aims to study stereological changes in intramyocardial blood vessels in rats submitted to nitric oxide (NO) synthesis inhibition within different periods. NO synthesis inhibition was achieved by administration of L-NAME (50 mg/kg/day); control and L-NAME rats were sacrificed 25 and 40 days after experimentation. Light microscopy and stereology [according to references 7, 13 and 14] were used for analyzing the myocardium. Arterial blood pressure and cardiac weight increased by 74.5% and 57.8% after 25 days and by 90.2% and 34.6% after 40 days, respectively. Comparing the L-NAME rats with corresponding controls revealed that the volume density of the vessels decreased by 31.3% after 40 days, and the length density by 53.5% after 25 days and by 25.7% after 40 days. The mean cross-sectional area of the vessels increased by 154.6% after 25 days. In this study on intramyocardial vessels, we observed an important decrease of the length density in L-NAME animals. Likewise, the volume density also decreased significantly in L-NAME animals. The mean cross sectional area of the vessels, which normally increases during cardiac growth between 25 and 40 days, was precociously increased in L-NAME animals at 25 days, suggesting that these animals suffer from a precocious increase of the heart (including blood vessels) due to pressure overload. Stereology of cardiac microvessels revealed remodeling of these vessels in rats under NO synthesis inhibition. Although these changes may be caused by NO inhibition and not by arterial hypertension, further comparative studies on different models of arterial hypertension are needed to confirm this hypothesis.

Specific liver autoreactivity in schistosomiasis mansoni

To investigate the possible involvement of autoimmune mechanisms in the development of hepatosplenic schistosomiasis (HSS), 234 patients with chronic Schistosoma mansoni infections were screened for a wide range of non-organ-specific autoantibodies as well as for antibodies reacting with the GOR peptide and with a liver-specific autoantigen, the hepatic asialoglycoprotein receptor (ASGP-R). Thirty-five (15.0%) were seropositive for antinuclear, smooth muscle or gastric parietal cell antibodies at low titres (< or = 1:80), and 15/176 (8.5%) had anti-GOR, all of whom had concomitant hepatitis C viral (HCV) infections. Anti-ASGP-R was found in 64 (27.4%) of the 234 patients at titres similar to those found in 18 untreated auto-immune hepatitis patients studied concurrently. Anti-ASGP-R seropositivity occurred significantly (P < 0.005) more frequently in patients with HSS (62/190, 32.6%) than in those with hepatointestinal schistosomiasis (2/44, 4.5%), but did not correlate with severity of liver disease or with the presence of the non-organ-specific autoantibodies. Anti-ASGP-R was found significantly (P < < 0.0005) less frequently in HSS patients who had had a splenectomy for portal hypertension (5/86, 5.8%) than in those who had not had a splenectomy (57/104, 54.8%). The findings suggest that liver-specific autoreactivity may play a role in the development of HSS.

Stereology of the myocardium in hypertensive rats. Differences in relation to the time of inhibition of nitric oxide synthesis

Structural changes in the myocardium following inhibition of nitric oxide synthesis were studied quantitatively within two different periods. Four groups of 10 rats were studied: control and L-NAME (NG-nitro-methyl-ester-L-arginine) groups for 25 and for 40 days. L-NAME was administered at 50 mg/kg per day in the drinking water. On the 26th and 41st days, the hearts were examined. Volume densities of myocytes (Vv[m]), cardiac interstitium (Vv[int], numerical density of myocytes (Nv[m]) and mean cross-sectional area of the myocytes (A[m]) were determined. Comparing the L-NAME animals with their respective controls showed the arterial pressure (AP) and the heart weight (HW) to be increased in the L-NAME animals. At 25 days, and more obviously at 40 days, the myocytes were hypertrophied with increase of myofibrils (A[m], greater in L-NAME rats). There were some areas with ischaemic lesions, inflammatory infiltrates and perivascular and interstitial fibrosis. The intramyocardial arteries had a thick tunica media and tunica intima. At 25 days the myocardium showed no stereological difference between L-NAME and controls, but by 40 days there was decreased Vv[m] and Nv[m] and increased Vv[int] in the exposed group. Inhibition of NO synthesis provoked a time progressive myocardial change, quantified by stereology.

[Morphology and stereology of the myocardium in hypertensive rats. Correlation with the time of nitric oxide synthesis inhibition]

PURPOSE

To study structural changes of the myocardium in relation to the time of nitric oxide synthesis inhibition.

METHODS

Four groups of 10 rats each were studied: 2 control groups and 2 groups with administration of L-Name (50 mg/kg/day), one during 25 days and the other during 40 days. The animals were then sacrificed and the hearts were prepared for study in light microscopy, where sections strained by picro-sirius were studied with and without polarized light for analysis of the cardiac interstitium collagen. Volume densities of myocytes (Vv[m]) and interstitium (Vv[int]), the numerical density of myocytes (Nv[m]) and the mean cross-sectional area of myocytes were (A[m]) also determined.

RESULTS

The L-Name animals were compared with the respective controls. In the L-Name rats, the tail arterial pressure increased 74.5 and 90.2% in the 25 days group and in the 40 days group, respectively. The heart weight increased 50% in the 25 days group and 28.6% in the 40 days group. The myocardium of the L-Name animals presented myocyte hypertrophy with increased A(m), perivascular and interstitial fibrosis, thickness of the tunica intima and tunica media of the intramyocardial arteries. In the 40 days group the L-Name animals had decreased Vv(m) and Nv(m) and increased Vv(int).

CONCLUSIONS

Inhibition of nitric oxide synthesis provokes myocardial changes that progress with the time of L-Name administration. The stereology is useful to determine and to evaluate the myocardial changes in this model of arterial hypertension.

Influence of Computer-aided Design/Computer-aided Manufacturing Diamond Bur Wear on Marginal Misfit of Two Lithium Disilicate Ceramic Systems

CLINICAL RELEVANCE

Marginal misfit of monolithic lithium disilicate ceramic crowns obtained from a chairside computer-aided design/computer-aided manufacturing system is affected after successive millings using a single diamond bur set. This fact can be critical for the longevity of indirect restorations.

SUMMARY

Volume-weighted mean nuclear volume and numerical nuclear density in the cardiomyocyte following enalapril and verapamil treatment

The estimation of the volume-weighted mean nuclear volume, nu(nu), and the numerical nuclear density in the plane, N(A), was used to analyze cardiomyocyte nuclei in the condition of cardiac hypertrophy caused by nitric oxide (NO) synthesis blockade and simultaneous antihypertensive treatment for 40 days (four groups of ten rats each: control, L-NAME, L-NAME+enalapril, L-NAME+verapamil). The blood pressure (BP) increased 71% in the L-NAME group. In the L-NAME+enalapril and L-NAME+verapamil groups, the BP did not show any alteration when compared with the respective controls. In comparison with the control group, nu(nu) was 250% greater, and the N(A) was 25% smaller in the L-NAME animals, while no difference occurred in the other two groups. With respect to cardiomyocyte nuclear size, the present results suggest a beneficial effect of the angiotensin-converting enzyme inhibitor enalapril and the calcium channel blocker verapamil when NO synthesis is blockaded.