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This study was undertaken to model the relationship between clonazepam plasma concentrations and a central nervous system adverse effect (impairment of the psychomotor performance) following the oral administration of immediate-release tablets of clonazepam in healthy volunteers. Such a (P)pharmacokinetic/(P)pharmacodynamic (PK/PD) study is important to interpret properly the consequences of determined levels of plasma concentrations of psychoactive therapeutic drugs reported to be involved in road-traffic accidents. Twenty-three male subjects received a single oral dose of 4 mg clonazepam. Plasma concentration, determined by on-line solid phase extraction coupled with high-performance liquid chromatography tandem mass spectrometry, and psychomotor performance, quantified through the Digit Symbol Substitution Test, were monitored for 72 hours. A 2-compartment open model with first order absorption and lag-time better fitted the plasma clonazepam concentrations. Clonazepam decreased the psychomotor performance by 72 +/- 3.7% (observed maximum effect), 1.5 to 4 hours (25th-75th percentile) after drug administration. A simultaneous population PK/PD model based on a sigmoid Emax model with time-dependent tolerance described well the time course of effect. Such acute tolerance could minimize the risk of accident as a result of impairment of motor skill after a single dose of clonazepam. However, an individual analysis of the data revealed a great interindividual variation in the relationship between clonazepam effect and plasma concentration, indicating that the phenomenon of acute tolerance can be predicted at a population, but not individual, level.

Objective: To evaluate 16S ribosomal RNA (rRNA) gene amplification to diagnose spontaneous bacterial peritonitis (SBP)., Patients and Methods: According to a retrospective protocol, 31 patients with portal hypertensive ascites (serum to ascites albumin gradient > or = 1.1 g/dL) were studied. Ascitic fluid was analyzed as follows: Gram stain, aerobic and anaerobic cultures, polymorphonuclear cell count, and biochemical tests. Bacterial DNA was detected by polymerase chain reaction., Results: There were 8 episodes of SBP and 4 episodes of bacterascites (BA). Culture was positive in 4 of 8 cases of SBP and bacterial DNA was positive in 7 of 8 cases of SBP. Bacterial DNA was positive in 3 of 4 cases of BA and in 8 of 28 cases of culture-negative non-neutrocytic ascites (CNNNA). The PELD score, serum to albumin ascites gradient, and mortality showed no statistical difference between patients with CNNNA and the result of the bacterial DNA analysis., Conclusions: Although the 16S rRNA gene amplification was better than culture to diagnose SBP, bacterial DNA does not seem to allow a distinction between ascites infection and ascites colonization.

Objectives: To determine the prevalence of spontaneous bacterial peritonitis, ascites with bacterial infection and noninfected ascites in pediatric patients with portal hypertensive ascites and to compare the clinical and laboratory features of infected and noninfected ascites., Methods: Forty-one episodes of portal hypertensive ascites (serum-ascites albumin gradient >1.1 g/dL) in 31 patients were studied. Median age was 2.9 years. Twenty-four (77.4%) patients were cirrhotic and 20 (83.3%) were classified as Child-Pugh C. Median pediatric end-stage liver disease score was 18.5. The following ascites features were assessed: polymorphonuclear neutrophil cell count, cytology, pH, concentration of glucose, lactic dehydrogenase, total protein and albumin, Gram stain and bacteriological culture. Blood was sampled for complete blood count, coagulation studies, liver and renal function tests. Groups were compared by Mann-Whitney and chi tests (P < 0.05)., Results: Noninfected ascites were observed in 29 of 41 samples, spontaneous bacterial peritonitis in eight of 41 and ascites with bacterial infection in four of 41. The most prevalent clinical features were fever, voluminous ascites and encephalopathy, but there were no significant differences in the clinical features of the groups. All patients with infected ascites were cirrhotic. There was no statistical difference in Child-Pugh or pediatric end-stage liver disease status between patients with infected and noninfected ascites. Culture of ascetic fluid was positive in four of eight cases of spontaneous bacterial peritonitis. Gram-negative rods were the most prevalent bacteria cultured. Except for serum albumin, no statistical differences in biochemical markers were observed between patients with infected and noninfected ascites., Conclusions: The prevalence of infected ascites was 29.2%. With the exception of serum albumin, there were no differences in the clinical and biochemical features of patients with infected ascites and noninfected ascites.

Objectives: Hepatitis A vaccine has not been investigated in children with Down syndrome. The aim of this study was to evaluate immunogenicity and safety of an inactivated hepatitis A vaccine in noninstitutionalized children with Down syndrome and compare their responses to those of healthy control children., Methods: An open, prospective, controlled trial of 127 children ages 1 to 12 years, 63 with Down syndrome and 64 healthy control subjects, was conducted at a single hospital. Inactivated hepatitis A virus (HAV) vaccine containing 720 enzyme-linked immunosorbent assay units of alum-adsorbed HAV was administered intramuscularly in a two-dose schedule at 0 and 6 months. Seroconversion and anti-HAV titers were measured at months 1 and 7., Results: Seroconversion rates at month 1 were 92% and 94% and geometric mean titers (GMT) were 164.02 and 160.77 mIU/mL in the Down syndrome (DS) and control groups, respectively. At month 7, seroconversion rates were 100% in both groups, with GMT of 1,719.86 and 2,344.90 mIU/mL in the DS and control groups, respectively (P = 0.117). Both doses were well tolerated and no significant adverse events observed. Local reaction at the injection site was the most common adverse event reported in both groups (15% in DS and 11% in controls)., Conclusions: The authors' data demonstrate a good response to HAV vaccination in children with DS living at home, with GMT not statistically different from that of healthy control children. HAV vaccine is well tolerated and highly immunogenic in children with DS.

Background: Acute hepatitis A superimposed on chronic liver disease has been associated with a more severe course of disease and development of fulminant hepatitis. The aim of this study was to evaluate the immunogenicity and safety of an inactivated hepatitis A virus vaccine in children with chronic liver disease., Patients and Methods: This was an open, prospective, and controlled trial with 89 anti-HAV negative children between 1 and 16 years of age studied at a pediatric liver disease and transplantation referral center. Inactivated HAV vaccine (Havrix), from GlaxoSmithKline Biologicals containing 720 Elisa units of alum-adsorbed hepatitis A antigen per 0.5 ml dose was used. Thirty-four pediatric patients with chronic liver disease (mean age: 7.0 +/- 4.86 years) and 55 healthy controls (mean age: 4.8 +/- 2.7 years) received two doses of Havrix vaccine in months zero and six. Seroconversion and anti-HAV titers expressed as geometric mean titers (GMT) in mIU/ml were measured at months one and seven, by a modified Hepatitis A virus antibodies (HAVAB) assay., Results: Seroconversion rates at four weeks after primary immunization were 76% and 94% and the GMT 107.77 and 160.77 mIU/ml in the patient and control groups, respectively. One month after second dose the seroconversion rates were 97% and 100% in the groups with GMT of 812.40 and 2,344.90 mIU/ml. Both doses were well tolerated with no significant adverse events observed. Local injection-site symptoms were the most common reactions reported in both groups., Conclusion: Although GMTs were significantly lower in children with chronic liver disease compared to healthy controls, the overall seroconversion rates were not different. Hepatitis A virus vaccine was safe, well-tolerated, and immunogenic in children with chronic liver disease.

The occurrence of anomia specifically affecting the ability to name animals is described in three patients. This deficit is contrasted with their capacity to name actions and tools. It is suggested that it is easier to access the names of 'operative' items, which were learned through both visual and sensorimotor experience, than the names of 'figurative' items, which were primarily learned through the visual modality. This hypothesis is consistent with the infero-temporal location of brain damage in these patients. Their ability to retrieve knowledge about operative items is assumed to be due to the sparing of the occipito-parietal area. Because the impairment also involves the recognition of animals, the likely locus of damage is the semantic component of the processing system.