Predicting inferior vena cava (IVC) filter retrievability using positional parameters: A comparative study of various filter types

Purpose

To compare changes in inferior vena cava (IVC) filter positional parameters from insertion to removal and examine how they affect retrievability amongst various filter types.

A meta-analysis of the efficacy of venlafaxine extended release 75–225 mg/day for the treatment of major depressive disorder

Objective: To evaluate the short-term efficacy of venlafaxine extended release (ER) 75–225?mg/day compared with placebo for treating major depressive disorder (MDD) and to examine associations between baseline characteristics and efficacy outcomes in MDD patients treated with venlafaxine ER 75–225?mg/day.

Research design and methods: This meta-analysis included published and unpublished short-term, double-blind, placebo-controlled, Wyeth/Pfizer sponsored studies of venlafaxine ER at doses up to 225?mg/day in adults with MDD.

Clinical trial registration: All trials were conducted before trial registration became mandatory.

Main outcome measures: Change from baseline in the 17-item Hamilton Rating Scale for Depression (HAM-D₁₇) total score was analyzed over time using a mixed-effects model for repeated measures with terms for study, treatment group, visit, interaction between treatment group and visit, and baseline score as a covariate. Associations between baseline demographic and clinical characteristics and the probability of HAM-D₁₇ response and remission at week 8 were evaluated using logistic regression models, with terms for study, treatment group, and baseline characteristics in the models. Safety and tolerability was assessed based on adverse events (AEs) and discontinuations due to AEs.

Results: The full analysis set included 1087 patients from five studies that fulfilled selection criteria. Statistically significant separation between venlafaxine ER and placebo groups for HAM-D₁₇ total score was seen at week 2 and all subsequent assessments (p-values <.0001). There was no significant interaction between treatment and baseline HAM-D₁₇ total score. Probability of HAM-D₁₇ remission at week 8 decreased with increasing baseline HAM-D₁₇ total score (p?=?.0012; OR: 0.94); however, baseline HAM-D₁₇ total score did not predict response. Discontinuations due to AEs were reported for 9.4% of venlafaxine-ER-treated patients compared with 3.6% of placebo-treated patients.

Key limitations: Five studies met the criteria for inclusion. Several differences in design between included studies limited the analysis: one study did not include a week 3 assessment (the week 3 time point was therefore dropped from the analysis), one study had two venlafaxine ER dose arms, which were combined into one group for the meta-analysis, and mixed- and flexible-dose studies were pooled.

Conclusions: Venlafaxine ER 75–225?mg/day effectively reduced symptoms of depression in patients with MDD overall and in patients with either lower (≤23) or higher (>23) HAM-D₁₇ total score at baseline.     

A(H1N1) pandemic influenza and its prevention by vaccination: Paediatricians' opinions before and after the beginning of the vaccination campaign

Background  

In June 2009, the World Health Organization declared an A(H1N1) influenza pandemic. In October 2009, the largest vaccination campaign in Canadian history began. The aim of this study was to document paediatricians' knowledge, attitudes and practices (KAP) regarding A(H1N1) pandemic influenza and its prevention by vaccination just after the beginning of the A(H1N1) vaccination campaign and to compare the results with those obtained before campaign initiation.     

Intra-arterial injection of iodine-131-labeled lipiodol for treatment of hepatocellular carcinoma.

BACKGROUND/AIM: The therapeutic effect of intra-arterial injection of 131-iodine-labeled lipiodol for treatment of hepatocellular carcinoma in palliative or adjuvant settings has been promising. We report, the results of an open study of this therapy in cirrhotic patients with small hepatocellular carcinoma. PATIENTS AND METHOD: Forty patients with hepatocellular carcinoma were given intra-arterial injections of 131-iodine-labeled lipiodol. These injections were repeated if necessary every 3 months. Tumor response (WHO criteria) was determined on CT scans performed after each treatment and every 3 months during the follow-up. Side effects and the cause of death were recorded. Therapeutic response and survival were analyzed. RESULTS: The median number of treatment was 2 (1-4). There was one complete response, 18 partial responses (47.5% response rate); 19 had stable disease and 2 progressions. Overall survival rates (+/-CI 95%) at 1, 2 and 3 years were: 90+/-4.7%, 60.3+/-8%, and 39+/-8.3%, respectively. Median survival was 27 months; 25 patients have died (4-56 months), 8 of tumor progression with a multifocal spread in the liver. Tolerance was good except for 2 patients who develop a fatal drug-related pulmonary insufficiency. CONCLUSION: These data suggest that intra-arterial therapeutic injection of 131-iodine-labeled lipiodol for treatment of hepatocellular carcinoma can provide high rate response and long survival for individuals not eligible for surgery or local treatment.     

Aldosterone metabolism and transepithelial potential difference in normal and cystic fibrosis subjects

The transepithelial potential difference (PD) is raised across cystic fibrosis (CF) respiratory epithelia. This raised voltage reflects active sodium absorption across a relatively chloride impermeable membrane. Because relatively little is known about the regulation of the rate of sodium absorption across mammalian airways, we assessed the possible contribution of aldosterone to the PD in normal and CF respiratory epithelia. Aldosterone excretion in five CF patients was 12.2 +/- 0.9 micrograms/24 h, a mean value not different from normal control subjects (13.6 +/- 1.5 micrograms/24 h, n = 5). Despite similar aldosterone excretion rates, nasal PD was more than 2-fold greater in the CF patients (-53.6 +/- 6.4 mV) than normal subjects (-21.3 +/- 1.4 mV). The effect of an aldosterone antagonist, spironolactone, on aldosterone excretion and nasal and rectal PD was evaluated in four CF patients and five normal subjects. During spironolactone administration, aldosterone excretion increased (2- to 4-fold) and rectal PD decreased in both groups. However, nasal PD was unchanged in each group (CF = -52.1 +/- 4.3 mV pre, -53.6 +/- 1.4 mV during; normal = -21.2 +/- 3.1 mV pre, -21.6 +/- 3.2 mV during). We conclude that neither increased aldosterone secretion rates nor organ sensitivity to aldosterone can account for the abnormally raised PD that characterizes the respiratory epithelium of subjects with CF.     

Oxygen consumption and ouabain binding sites in cystic fibrosis nasal epithelium

Ion transport by the epithelium lining the airways of patients with cystic fibrosis (CF) is characterized by a raised transepithelial PD and an increased amiloride sensitivity (1). These properties could arise from normal sodium transport across an epithelium with decreased cell chloride permeability and limited chloride secretion. Alternatively, a higher than normal rate of sodium absorption could contribute to these abnormalities. We investigated the latter possibility by measuring oxygen consumption and specific ouabain binding of CF and atopic polyp epithelia and normal turbinate epithelium. Tissue from CF patients consumed oxygen at a rate that was two to three times that of non-CF tissues and had 60% more ouabain binding sites than non-CF epithelium. These results are not consistent with an isolated defect in chloride permeability but support recent findings that the sodium conductance of the apical cell membrane and net sodium absorption by CF nasal epithelium are greater than those of non-CF nasal epithelium.     

An overview of the pathogenesis of cystic fibrosis lung disease

The pathogenesis of cystic fibrosis (CF) lung disease is reviewed, focusing on an overview of the physiologic mechanisms that regulate mucus transport. A major emphasis is placed on the active transport systems that regulate the airway surface liquid (ASL) volume and, particularly, regulate the volume of the periciliary liquid (PCL) layer. A sequence is developed for CF whereby there is a depletion of the PCL that reflects the combined dysfunctions of accelerated Na(+)-dependent volume absorption and failure to secrete Cl(-). Both dysfunctions are a direct consequence of missing cystic fibrosis transmembrane conductance regulator (CFTR) at the apical membrane of airway epithelial cells. PCL depletion leads to failure of mucus transport, which is associated with persistent mucin secretion and formation of adherent mucus plaques and plugs. These plugs become the nidus for persistent bacterial airway infections that ultimately lead to a markedly anaerobic luminal environment.     

Oxidation of N-hydroxyguanidines by cytochromes P450 and NO-synthases and formation of nitric oxide

Microsomal cytochromes P450 and tetrahydrobiopterin (BH4) free-NOS II catalyze the oxidation of N-hydroxyguanidines by NADPH and O2 with formation of nitrogen oxides including NO. These reactions are not selective in terms of substrates, as they occur on most N-hydroxyguanidines, and of products, as they not only lead to corresponding ureas but also to cyanamides. These non selective reactions are mainly due to O2- derived from the oxidase function of those hemeproteins. By contrast, NO synthase (NOS) containing BH4 catalyze the selective monooxygenation of some N-hydroxyguanidines by NADPH and O2 with formation of NO and the corresponding ureas in a 1:1 molar ratio. Those reactions are not inhibited by superoxide dismutase (SOD) and are performed by the NOS Fe(II)-O2 complex. The endogenous NOS substrate N(omega)-hydroxy-L-arginine (NOHA), and its close analogue homo-NOHA, are selectively oxidized in this manner by NOS whereas nor-NOHA and dinor-NOHA are not. Moreover, some non alpha-amino acid N-hydroxyguanidines act as NOS substrates in a manner similar to NOHA. This includes a small number of simple N-alkyl N'-hydroxyguanidines with R(alkyl) propyl, butyl, and pentyl, and some N-aryl N'-hydroxyguanidines that involve a relatively small and preferably electron-rich aryl substituent. The best exogenous substrate of NOS reported so far is N-butyl N'-hydroxyguanidine; this compound is oxidized by NOS II with formation of NO with a catalytic efficiency (kcat/Km) only two times lower than NOHA itself. N-butyl N'-hydroxyguanidine is also a good substrate for NOS I and NOS III. However, some N-aryl N'-hydroxyguanidines, with Ar = p-chlorophenyl and p-methylphenyl, are selective substrates of NOS II. These results show that exogenous N-hydroxyguanidines not bearing an alpha-amino acid function are efficiently and selectively oxidized by NOS with forrmation of NO. They open the way toward the research of new NO donors based on selective substrates of each class of NOS.