High prevalence of hepatitis B virus pre-s mutant in countries where it is endemic and its relationship with genotype and chronicity

It has been reported that hepatitis B virus (HBV) mutants carrying mutations in the pre-S region can be found in infected patients. In this study, we investigated the prevalence of the HBV variant with the pre-S mutant in different geographic regions, including countries with low and high levels of endemic HBV infection, and analyzed the correlation with clinical findings. We examined 387 HBV DNA-positive serum samples from individuals among 12 countries, consisting of Vietnam, Myanmar, Thailand, China, Korea, Nepal, Japan, Russia, Spain, United States, Bolivia, and Ghana. HBV pre-S mutants were detected in 71 (18.3%) of 387 serum samples tested. This mutant was the most prevalent in Vietnam (36%), followed by Nepal (27.3%), Myanmar (23.3%), China (22.4%), Korea (14.3%), Thailand (10.5%), Japan (7.7%), and Ghana (4.3%). In contrast, no case with this mutation was found in Russia, Spain, United States, and Bolivia. Among the HBV deletion mutations, 15.5% (11 of 71) occurred in the pre-S1 and 46.5% (33 of 71) in the pre-S2 regions. Eight (11.3%) cases had a mutation in both the pre-S1 and pre-S2 regions. In addition, a point mutation at the pre-S2 starting codon was observed in 19 (26.7%) cases. The detection rate of the HBV mutant in patients with hepatocellular carcinoma was significantly higher than in other patients (P < 0.05). Furthermore, these mutants were found more frequently in genotype B (25%) and genotype C (24.5%) than in the other genotypes (P < 0.05). Our results indicated that there was a high prevalence of HBV pre-S mutation in regions of endemic HBV infection in Asia. Furthermore, the pre-S mutation appeared to be correlated with hepatocellular carcinoma and HBV genotypes.     

Idiopathic pericardial effusion in patients with hypertrophic cardiomyopathy

The International Journal of Cardiovascular Imaging - The aims of this study were to examine the prevalence of moderate to large (moderate–large) idiopathic pericardial effusion (i-PEF) in...     

An integrated bioinformatics approach to the characterization of influenza A/H5N1 viral sequences by microarray data: Implication for monitoring H5N1 emerging strains and designing appropriate influenza vaccines

In order to characterize A/H5N1 viral sequences, a bioinformatics approach accurately identified viral sequences from discovery of a sequence signature, which provided enough distinctive information for sequence identification. Eight highly pathogenic H5N1 viral isolations were collected from different areas of Thailand between 2003 and 2006, and were used for analysis of H5N1 genotypic testing with a semiconductor-based oligonucleotide microarray. All H5N1 samples and H1N1, H4N8 negative controls were correctly subtyped. Sensitivity of the eight oligonucleotide probes, with optimized cut-offs, ranged from 70% (95% CI 65–75) to 87% (95% CI 84–91), and the corresponding Kappa values ranged from 0.76 (95% CI 0.72–0.80) to 0.86 (95% CI 0.83–0.89). Semi-conductor-based oligonucleotide array and oligonucleotide probes corresponded well when detecting H5N1. After fully correcting the subtype from the result of microarray signal intensity, the microarray output method combined with bioinformatics tools, identified and monitored genetic variations of H5N1. Capability of distinguishing different strains of H5N1 from Thailand was the outstanding feature of this assay. Ninety percent of HA and NA (4/5) genes were sequenced correctly, in accordance with previous examinations performed by classical diagnostic methods. The low-medium-high bioinformatics resolutions were able to predict an epidemic strain of H5N1. This study also showed the advantage of using a large genotypic database to predict the epidemic strain of H5N1. However, the monitoring protocol of this new strain has been recommended for further study with a large-scale sample.     

Magnetic resonance imaging assessment of cardiac function

Measurements of left ventricular function at rest and during stress are useful for identifying myocardial ischemia, injury, and the risk of subsequent myocardial infarction. Without ionizing radiation or intravascular contrast administration, magnetic resonance imaging techniques can be used to acquire precise measurements of left ventricular function. This relatively new development may enhance a physician’s ability to provide care to patients with cardiovascular disease.     

Dobutamine stress magnetic resonance imaging

Measurements of left ventricular function with cardiovascular magnetic resonance (CMR) at rest and during intravenous dobutamine are useful for identifying myocardial ischemia, viability, and the risk of subsequent cardiovascular events. Without ionizing radiation, intravascular iodinated contrast administration, or acoustic window limitations, CMR has emerged as a useful adjunct to transthoracic echocardiography for assessing patients with or suspected of having coronary artery disease.     

Bilateral pheochromocytoma during pregnancy

Background Pheochromocytoma is a rare disease of the chromaffin cells that secrete catecholamines. It may occur during pregnancy. Bilateral pheochromocytoma in pregnancy is even rarer.Case A 26-year-old woman, gravida 2, para 0-0-1-0, 18 weeks pregnancy, was initially seen with elevated blood pressure (170/100 mmHg) and mild headache. The cause of hypertension was conventionally investigated and bilateral pheochromocytoma was finally searched for and found. Bilateral adrenalectomy was undertaken at 23 weeks gestation and Cesarean section was performed at 31 weeks gestation due to intrauterine growth retardation (IUGR) and compromised fetal well-being. The maternal outcome was uneventful and the baby was physiologically complicated only by neonatal jaundice.Conclusion Pheochromocytoma should be searched for in the conventionally differential diagnosis in hypertension during pregnancy, especially in the young. Early diagnosis and proper management with medical treatment followed by surgical removal of the tumor usually result in good maternal and fetal outcomes.     

Cleaning of rotary nickel-titanium endodontic instruments

AIM: To develop and evaluate an effective cleaning procedure for rotary nickel-titanium (NiTi) endodontic instruments. METHODOLOGY: New rotary instruments (ProFile size 25/.04) were contaminated by preparing canals of extracted teeth. Three factors were evaluated to develop an effective cleaning sequence: dry or moist storage before cleaning; mechanical removal (brushing); and chemical dissolution in 1% NaOCl with ultrasonication. Debris on flutes was scored after staining in situ with Van Gieson's solution at x45 magnification. Debris was classified as stained or unstained particulate debris and organic film, and rated as none, slight, moderate or heavy. The effectiveness of a recommended cleaning sequence was tested on different instrument types and in private endodontic practices. RESULTS: All new instruments showed metallic spurs and fine particulate debris on the surfaces. After contamination, brushing alone removed most particulate debris, but did not remove organic film. NaOCl effectively removed organic film. Under laboratory conditions, the sequential cleaning procedures (moist storage, brushing followed by immersion in 1% NaOCl and ultrasonic cleaning) totally removed organic debris. Dry storage before cleaning or autoclaving with debris present reduced cleaning effectiveness (P<0.001, one-way ANOVA). In three private practices, the cleaning protocol substantially reduced biological contamination, but complete cleaning was not always achieved (87% clean). CONCLUSION: Complete removal of organic debris from instruments is feasible using a combination of mechanical removal and chemical dissolution, but requires meticulous attention to details.     

Acute aortic dissection: utilizing imaging modalities to improve detection

Acute aortic dissection is a serious condition in elderly patients and may become fatal rapidly if left undiagnosed and untreated. As pointed out by Welch et al1chest radiography is a screening test for this condition by detecting these signs such as widening mediastinum,blurring of the aortic knob, left apical cap, etc.……     

Use of stents to treat kinks causing obstruction in a left internal mammary artery graft

Left internal mammary arteries (LIMA) are used routinely as grafts to the left anterior descending coronary artery (LAD) in selected patients undergoing coronary artery bypass graft (CABG) surgery because of better long-term patency rates. Pathology other than fibrointimal hyperplasia, accelerated atherosclerosis, or thrombus can sometimes cause obstructive lesions in such grafts. This report illustrates a kink in a LIMA graft to the LAD causing an obstructive lesion shortly after surgery and describes the subsequent management of this lesion with intracoronary stents. Cathet. Cardiovasc. Intervent. 46:223–226, 1999. © 1999 Wiley-Liss, Inc.