Efficacy of propafenone in the treatment of ventricular hyperkinetic arrhythmias in subjects with a history of myocardial infarction

A placebo-controlled single-blind study was performed to evaluate the efficacy of oral propafenone on stable potentially malignant ventricular tachyarrhythmias in 13 patients who had suffered a myocardial infarction two months or longer before the trial. All patients exhibited at a 24 hour Holter monitoring a minimum mean frequency of 10 ventricular premature depolarizations (VPDs) per hour and repetitive VPDs. Ventricular tachyarrhythmias characterization was obtained by means of multiple Holter monitorings and exercise stress testings. Propafenone was considered as effective when a well-defined quantitative and qualitative reduction of ventricular tachyarrhythmias was reached. After an initial placebo phase, patients received propafenone 450 mg or 900 mg daily. Acute effectiveness of propafenone was proved in 8 on 13 patients (62%) who showed a significative reduction of VPDs (89%, p less than 0.02) and a suppression of the most complex forms of ventricular tachyarrhythmic events. The efficacy of propafenone was confirmed, three months later, in each patient, side effects were infrequent, minimal and of no clinical consequence. Oral propafenone can be considered as an effective drug for reducing the level of potentially malignant ventricular tachyarrhythmias in patients with previous myocardial infarction.     

The importance of gastric emptying in reflux esophagitis: an experimental research on pigs

A study was conducted on pigs to evaluate the importance of gastric emptying rate in reflux esophagitis development. Gastric emptying was previously measured in 25 pigs. Then, the following operative procedures were carried out: Heller's cardiomyotomy, common bile duct ligature, cholecysto-gastric anastomosis, and extramucosal duodenal myotomy on 10 animals (group A); the same procedures except extramucosal duodenal myotomy on another 10 animals (group B); common bile duct ligature and cholecysto-gastric anastomosis on the last 5 animals (group C). Six months later, gastric emptying was measured again; whereas in group A a significant shortening of gastric emptying was found, the other 2 groups remained unchanged. Then, all the animals were sacrificed and the lower third of the esophagus was removed for histologic examination. In all the pigs undergoing cardiomyotomy (groups A and B) appearance of esophagitis was found. No signs of esophagitis were found in group C. The conclusions reached are cardiomyotomy is in all cases responsible for reflux esophagitis development; extramucosal duodenal myotomy is capable of shortening gastric emptying, but this does not affect reflux esophagitis development.     

Novel nonnucleoside inhibitor of hepatitis C virus RNA-dependent RNA polymerase

A novel nonnucleoside inhibitor of hepatitis C virus (HCV) RNA-dependent RNA polymerase (RdRp), [(1R)-5-cyano-8-methyl-1-propyl-1,3,4,9-tetrahydropyano[3,4-b]indol-1-yl] acetic acid (HCV-371), was discovered through high-throughput screening followed by chemical optimization. HCV-371 displayed broad inhibitory activities against the NS5B RdRp enzyme, with 50% inhibitory concentrations ranging from 0.3 to 1.8 microM for 90% of the isolates derived from HCV genotypes 1a, 1b, and 3a. HCV-371 showed no inhibitory activity against a panel of human polymerases, including mitochondrial DNA polymerase gamma, and other unrelated viral polymerases, demonstrating its specificity for the HCV polymerase. A single administration of HCV-371 to cells containing the HCV subgenomic replicon for 3 days resulted in a dose-dependent reduction of the steady-state levels of viral RNA and protein. Multiple treatments with HCV-371 for 16 days led to a >3-log10 reduction in the HCV RNA level. In comparison, multiple treatments with a similar inhibitory dose of alpha interferon resulted in a 2-log10 reduction of the viral RNA level. In addition, treatment of cells with a combination of HCV-371 and pegylated alpha interferon resulted in an additive antiviral activity. Within the effective antiviral concentrations of HCV-371, there was no effect on cell viability and metabolism. The intracellular antiviral specificity of HCV-371 was demonstrated by its lack of activity in cells infected with several DNA or RNA viruses. Fluorescence binding studies show that HCV-371 binds the NS5B with an apparent dissociation constant of 150 nM, leading to high selectivity and lack of cytotoxicity in the antiviral assays.     

Platelet transfusions in the neonatal intensive care unit:factors predicting which patients will require multiple transfusions

BACKGROUND: Previous studies suggest that recombinant thrombopoietin (rTPO) will increase platelet production in thrombocytopenic neonates. However, the target populations of neonates most likely to benefit should be defined. Studies suggest that rTPO will not elevate the platelet count until 5 days after the start of treatment. Therefore, the neonates who might benefit from rTPO are those who will require multiple platelet transfusions for more than 5 days. This study was designed to find means of prospectively identifying these patients. STUDY DESIGN AND METHODS: A historic cohort study of all patients in the neonatal intensive care unit (NICU) at the University of Florida who received platelet transfusions from January 1, 1997, through December 31, 1998, was conducted. RESULTS: Of the 1389 patients admitted to the NICU during the study period, 131 (9.4%) received platelet transfusions. Seventeen were treated with extracorporeal membrane oxygenation and were excluded from further analysis. Of the remaining 114 patients, 55 (48%) received one transfusion and 59 (52%) received more than one transfusion (21 had >4). None of the demographic factors examined predicted multiple platelet transfusions. However, two clinical conditions did; liver disease and renal insufficiency. Neonates who received one platelet transfusion had a relative risk of death 10.4 times that in neonates who received none (p = 0.0001). Neonates who received >4 platelet transfusions had a risk of death 29.9 times that in those who received no transfusions (p = 0.0001). CONCLUSION: NICU patients with liver disease or renal insufficiency who receive one platelet transfusion are likely to receive additional transfusions. Therefore, these patients constitute a possible study population for a Phase I/II rTPO trial.     

Helicobacter pylori upregulates expression of epidermal growth factor-related peptides, but inhibits their proliferative effect in MKN 28 gastric mucosal cells.

Acute exposure to Helicobacter pylori causes cell damage and impairs the processes of cell migration and proliferation in cultured gastric mucosal cells in vitro. EGF-related growth factors play a major role in protecting gastric mucosa against injury, and are involved in the process of gastric mucosal healing. We therefore studied the acute effect of H. pylori on expression of EGF-related growth factors and the proliferative response to these factors in gastric mucosal cells (MKN 28) derived from gastric adenocarcinoma. Exposure of MKN 28 cells to H. pylori suspensions or broth culture filtrates upregulated mRNA expression of amphiregulin (AR) and heparin-binding EGF-like growth factor (HB-EGF), but not TGFalpha. This effect was specifically related to H. pylori since it was not observed with E. coli, and was independent of VacA, CagA, PicA, PicB, or ammonia. Moreover, H. pylori broth culture filtrates stimulated extracellular release of AR and HB-EGF protein by MKN 28 cells. AR and HB-EGF dose-dependently and significantly stimulated proliferation of MKN 28 cells in the absence of H. pylori filtrate, but had no effect in the presence of H. pylori broth culture filtrates. Inhibition of AR- or HB-EGF- induced stimulation of cell growth was not mediated by downregulation of the EGF receptor since EGF receptor protein levels, EGF binding affinity, number of specific binding sites for EGF, or HB-EGF- or AR-dependent tyrosine phosphorylation of the EGF receptor were not significantly altered by incubation with H. pylori broth culture filtrates. Increased expression of AR and HB-EGF were mediated by an H. pylori factor > 12 kD in size, whereas antiproliferative effects were mediated by both VacA and a factor < 12 kD in size. We conclude that H. pylori increases mucosal generation of EGF-related peptides, but in this acute experimental model, this event is not able to counteract the inhibitory effect of H. pylori on cell growth. The inhibitory effect of H. pylori on the reparative events mediated by EGF-related growth factors might play a role in the pathogenesis of H. pylori-induced gastroduodenal injury.     

Recurrent acute hepatitis associated with use of cetirizine

OBJECTIVE: To describe a case of recurrent acute hepatitis related to the use of cetirizine, a selective histamine(1)-receptor antagonist approved for the treatment of common allergic diseases. CASE SUMMARY: A 26-year-old man was hospitalized with a week-long history of weakness, nausea, anorexia, and hyperchromic urine, which had developed after 6 days of therapy with oral cetirizine 10 mg/day for allergic rhinitis. Admission laboratory testing revealed evidence of acute hepatitis and seropositivity for liver-kidney microsome antibodies. Liver biopsy findings of diffuse portal tract and lobular inflammation with a prominent eosinophilic infiltrate were consistent with drug-related hepatitis. The patient was discharged after one week of treatment with tocopherol and glutathione. Three months after discharge, transaminase levels were normal. At 6 months, seropositivity for liver-kidney microsome antibodies was still present, but considerably less intense. The patient had suffered 2 previous episodes of "acute hepatitis of unknown origin," and both had occurred after cetirizine use. DISCUSSION: Use of the Naranjo probability scale indicated cetirizine as the probable cause of acute hepatitis, and the positivity for liver-kidney microsome antibodies is suggestive of an autoimmune mechanism for liver damage. As of September 13, 2004, ours is the fourth reported case of acute hepatitis associated with cetirizine and the second in which liver-kidney microsome antibodies have been documented. CONCLUSIONS: Although cetirizine is considered to have low potential for severe hepatic toxicity, the possibility that it can provoke autoimmune-mediated hepatotoxicity should be considered.     

Decrease of total, glutathione and cysteine SH in non-alcoholic cirrhosis

The content of plasma thiols was determined in 42 patients with non-alcoholic cirrhosis. Total thiols were evaluated by Ellman's method, glutathione and cysteine by HPLC in fluorescence. Cirrhotic patients showed a significant decrease in plasma thiol content with respect to a control group of 32 healthy subjects, as total sulphydryls as well as glutathione and cysteine. The thiol decrease does not seem to be related to nutritional status or dietetic factors. Our data indicate that liver cirrhosis, independently from alcohol abuse, produces a decrease in all plasma thiols, probably secondary to a complex alteration of the transsulfuration pathway.     

Cortical responses to consciousness of schematic emotional facial expressions: A high‐resolution EEG study

Is conscious perception of emotional face expression related to enhanced cortical responses? Electroencephalographic data (112 channels) were recorded in 15 normal adults during the presentation of cue stimuli with neutral, happy or sad schematic faces (duration: “threshold time” inducing about 50% of correct recognitions), masking stimuli (2 s), and go stimuli with happy or sad schematic faces (0.5 s). The subjects clicked left (right) mouse button in response to go stimuli with happy (sad) faces. After the response, they said “seen” or “not seen” with reference to previous cue stimulus. Electroencephalographic data formed visual event‐related potentials (ERPs). Cortical sources of ERPs were estimated by LORETA software. Reaction time to go stimuli was generally shorter during “seen” than “not seen” trials, possibly due to covert attention and awareness. The cue stimuli evoked four ERP components (posterior N100, N170, P200, and P300), which had similar peak latency in the “not seen” and “seen” ERPs. Only N170 amplitude showed differences in amplitude in the “seen” versus “not seen” ERPs. Compared to the “not seen” ERPs, the “seen” ones showed prefrontal, premotor, and posterior parietal sources of N170 higher in amplitude with the sad cue stimuli and lower in amplitude with the neutral and happy cue stimuli. These results suggest that nonconscious and conscious processing of schematic emotional facial expressions shares a similar temporal evolution of cortical activity, and conscious processing induces an early enhancement of bilateral cortical activity for the schematic sad facial expressions (N170). Hum Brain Mapp, 2010. © 2010 Wiley‐Liss, Inc.