An overview of chagasic cardiomyopathy: pathogenic importance of oxidative stress

There is growing evidence to suggest that chagasic myocardia are exposed to sustained oxidative stress-induced injuries that may contribute to disease progression. Pathogen invasion- and replication-mediated cellular injuries and immune-mediated cytotoxic reactions are the common source of reactive oxygen species (ROS) in infectious etiologies. However, our understanding of the source and role of oxidative stress in chagasic cardiomyopathy (CCM) remains incomplete. In this review, we discuss the evidence for increased oxidative stress in chagasic disease, with emphasis on mitochondrial abnormalities, electron transport chain dysfunction and its role in sustaining oxidative stress in myocardium. We discuss the literature reporting the consequences of sustained oxidative stress in CCM pathogenesis.     

Caudal anesthesia in pediatric cardiac surgery: does it affect outcome?

OBJECTIVE: The purpose of this study was to examine the influence of caudal anesthesia on outcomes (pediatric intensive care unit [PICU] length of stay, hospital length of stay, ventilatory time, early extubation rate) in pediatric patients undergoing congenital heart disease repair requiring cardiopulmonary bypass (CPB). DESIGN: Retrospective. SETTING: University teaching hospital. PARTICIPANTS: Pediatric patients undergoing surgery to treat congenital heart disease between 1999 and 2002. INTERVENTION: None. MEASUREMENTS AND MAIN RESULTS: Thirty-four patients with atrial septal defect (ASD), 37 with ventricular septal defect, and 46 with tetralogy of Fallot (TOF) were included in the analysis. No differences were found in preoperative and intraoperative data between caudal and noncaudal group for each disorder. There was no difference between caudal and noncaudal groups in PICU and hospital stay. A statistically significant difference was found in the postoperative ventilatory time in patients with ASD and TOF between caudal and noncaudal groups. The early extubation rate was higher in the TOF caudal group compared with the noncaudal group. CONCLUSIONS: This retrospective study demonstrated that postinduction placement of caudal anesthesia does not affect PICU or hospital length of stay. A well-controlled prospective study is needed to confirm these findings.     

Use of biopolymer membrane diplen-F in treatment of initial enamel carious lesion on smooth surfaces

The aim of the study was to evaluate the possibility of using a fluoride product included in a biodegradable membrane in remineralization of initial enamel carious lesions. The membrane has anti-bacterial, anti-inflammatory and remineralization properties, with a long-term effect. The efficiency of this treatment was assessed by measuring the surface of the demineralization area and its depth. The results proved that the use of this membrane in association with remineralization therapy of the initial enamel carious lesions increase the chances of success and represents a simple solution easily accepted by the patients.     

Vigabatrin in low doses selectively suppresses the clonic component of audiogenically kindled seizures in rats

PURPOSE: The effect of systemic administration of the gamma-aminobutyric acid (GABA)-transaminase inhibitor vigabatrin (VGB) on different components of convulsions was tested in the model of audiogenically kindled seizures, which consist of brainstem (running, tonus) and forebrain (clonus) elements. METHODS: Audiogenically susceptible rats of Krushinsky-Molodkina (KM), Wistar, and WAG/Rij strains received repeated sound stimulation (60 dB, 10-80 kHz) until kindled audiogenic seizures were reliably elicited. Kindled audiogenic seizures consisted of running, tonic, and generalized clonic phases in KM rats (severe audiogenic seizures) and of running and Racine stage 5 facial/forelimb clonus in Wistar and WAG/Rij rats (moderate seizures). Vehicle, 100, or 200 mg/kg of VGB was intraperitoneally injected 2, 4 and 24 h before the induction of kindled audiogenic seizures. RESULTS: At both doses, VGB did not change the seizure latency and the duration of running and tonic convulsions, but suppressed clonic ones in all rat strains. In KM rats, the mean duration of posttonic clonus was significantly reduced at 24 h after 100 mg/kg and from 4 h after 200 mg/kg. In Wistar and WAG/Rij rats, the mean duration of facial/forelimb clonus was reduced from 4 and 2 h after 100- and 200-mg/kg administration, respectively; 24 h after the high-dose injection, clonus was completely blocked in all rats of both strains. No difference in efficacy of VGB between Wistar and WAG/Rij rats was observed. CONCLUSIONS: VGB more effectively suppresses clonic convulsions than running and tonic ones in audiogenically kindled rats. It is supposed that this selective anticonvulsive effect of VGB results from different sensitivities of forebrain and brainstem epileptic networks to the presumed GABA enhancement.     

Acute neuropathy mimicking porphyria induced by aminolevulinic acid during photodynamic therapy

An 82-year-old man developed severe, acute, predominantly motor polyneuropathy, signs of autonomic involvement, and skin changes following aminolevulinic acid (ALA) administration. The compound was used as a prodrug for photodynamic therapy of Barrett's esophagitis. Changes were observed in various parameters of the heme pathway. The case reported represents a rare response to ALA treatment, resembling an acute attack of hepatic porphyria with neurological features.     

The hot skull sign on bone scans of obese patients resulting from disparate soft tissue attenuation

We have frequently observed diffusely increased skull activity on bone scans of obese patients, who do not have evidence of metabolic or metastatic bone disease. Skull activity of 25 obese patients were compared to that of age and sex-matched nonobese 25 patients visually and quantitatively. The results clearly indicated that diffusely increased skull activity is significantly more common on bone scans of obese patients because of disparate attenuation of overlying soft tissues. This knowledge will help obviate the need for additional radiologic and/or laboratory tests in search of other conditions associated with hot skull, ie, Paget's disease and metabolic bone disorders such as renal osteodystrophy and primary hyperparathyroidism.     

Viral infection and antiviral therapy in the neonatal intensive care unit

Viral diseases are leading causes of mortality and morbidity among infants requiring care in the neonatal intensive care unit (NICU), with ongoing discoveries of new viral pathology likely to add to the burdens posed. Many viral diseases in NICU infants are undiagnosed or appreciated only late in the course because of subtle or asymptomatic presentation, confusion with bacterial disease, and failure to consider viral disease. We present an overview of viral disease in NICU infants, with emphasis on pharmacologic agents currently employed for prophylaxis and treatment of such diseases. Advances in molecular biology and popular demand to develop antiviral agents for viral diseases (eg, human immunodeficiency virus) offer great promise for the future.     

A novel technique for quantifying changes in vascular density, endothelial cell proliferation and protein expression in response to modulators of angiogenesis using the chick chorioallantoic membrane (CAM) assay

Reliable quantitative evaluation of molecular pathways is critical for both drug discovery and treatment monitoring. We have modified the CAM assay to quantitatively measure vascular density, endothelial proliferation, and changes in protein expression in response to anti-angiogenic and pro-angiogenic agents. This improved CAM assay can correlate changes in vascular density with changes seen on a molecular level. We expect that these described modifications will result in a single in vivo assay system, which will improve the ability to investigate molecular mechanisms underlying the angiogenic response.