Clinical and Echocardiographic Factors Affecting Tricuspid Regurgitation Severity in the Patients with Lone Atrial Fibrillation.

BACKGROUND: Atrial fibrillation (AF) can be a risk factor for development of significant tricuspid regurgitation (TR). We investigated which clinical and echocardiographic parameters were related to severity of functional TR in patients with lone AF. METHODS: A total of 89 patients with lone AF were enrolled (75 ± 11 years; 48% male): 13 patients with severe TR, 36 patients with moderate TR, and 40 consecutive patients with less than mild TR. Clinical parameters and echocardiographic measurements including right ventricular (RV) remodeling and function were evaluated. RESULTS: Patients with more severe TR were older and had more frequently persistent AF (each p < 0.001). TR severity was related to right atrial area and tricuspid annular systolic diameter (all p < 0.001). The patients with moderate or severe TR had larger left atrial (LA) volume and increased systolic pulmonary artery pressure (SPAP) than the patients with mild TR (p = 0.04 for LA volume; p < 0.001 for SPAP). RV remodeling represented by enlarged RV area and increased tenting height was more prominent in severe TR than mild or moderate TR (all p < 0.001). Multivariate analysis showed type of AF, LA volume, tricuspid annular diameter and tenting height remained as a significant determinants of severe TR. In addition, tenting height was independently associated with the presence of severe TR (p = 0.04). CONCLUSION: In patients with lone AF, TR was related to type of AF, LA volume, tricuspid annular diameter and RV remodeling. Especially, tricuspid valvular tethering seemed to be independently associated with development of severe functional TR.

Evaluation of antimicrobial effects of commercial mouthwashes utilized in South Korea.

Streptococcus mutans is frequently associated with dental caries. Bacterial fermentation of food debris generates an acidic environment on the tooth surface, ultimately resulting in tooth deterioration. Therefore, various mouthwashes have been used to reduce and prevent Streptococcus mutans. The aim of this study was to evaluate the antimicrobial activities of 4 commercial mouthwashes and those of 10% and 20% ethanol solutions (formula A, B, C, D, E and F) against Streptococcus mutans using biofilm and planktonic methods. The range of reduction in the viable cell count of Streptococcus mutans as estimated by the biofilm and planktonic methods was 0.05-5.51 log (P ≤ 0.01) and 1.23-7.51 log (P ≤ 0.001) compared with the negative control, respectively, indicating that the planktonic method had a stronger antibacterial effect against S. mutans. Among the tested formulations, formula A (Garglin regular® mouthwash) was the most effective against Streptococcus mutans (P ≤ 0.001).

Simultaneous detection of waterborne viruses by multiplex real-time PCR.

Norovirus, Rotavirus group A, the Hepatitis A virus, and Coxsackievirus are all common causes of gastroenteritis. Conventional diagnoses of these causative agents are based on antigen detection and electron microscopy. To improve the diagnostic potential for viral gastroenteritis, internally controlled multiplex real-time polymerase chain reaction (PCR) methods have been recently developed. In this study, individual real-time PCRs were developed and optimized for specific detections of Norovirus genogroup I, Norovirus genogroup II, Rotavirus group A, the Hepatitis A virus, and Coxsackievirus group B1. Subsequently, individual PCRs were combined with multiplex PCR reactions. In general, multiplex real-time PCR assays showed comparable sensitivities and specificities with individual assays. A retrospective clinical evaluation showed increased pathogen detection in 29% of samples using conventional PCR methods. Prospective clinical evaluations were detected in 123 of the 227 (54%) total samples used in the multiplex real-time PCR analysis. The Norovirus genogroup II was found most frequently (23%), followed by Rotavirus (20%), the Hepatitis A virus (4.5%), Coxsackievirus (3.5%), and Norovirus genogroup I (2.6%). Internally controlled multiplex real-time PCR assays for the simultaneous detection of Rotavirus, Coxsackievirus group B, the Hepatitis A virus, and Norovirus genogroups I and II showed significant improvement in the diagnosis of viral gastroenteritis.

Standardized positive controls for detection of norovirus by reverse transcription PCR.

BACKGROUND: Norovirus is one of the most common causes of nonbacterial gastroenteritis in humans. Rapid spread by contaminated food and person-to-person transmission through the fecal-oral route are characteristics of norovirus epidemiology and result in high morbidity in vulnerable patient populations. Therefore, detection of norovirus is a major public health concern. Currently, the most common method for detecting and differentiating among norovirus strains in clinical and environmental samples is reverse transcription PCR (RT-PCR). Standardized positive controls used in RT-PCR assays to detect norovirus are designed to overcome the problem of false-negative results due to PCR inhibitors and suboptimal reaction conditions. RESULTS: In the current study, four types of RNA transcripts were produced from plasmids: norovirus GI-5 and GII-4 capsid regions with human rotavirus (VP7 gene derived) fragment insertions, and norovirus GI-6 and GII-4 capsid regions with hepatitis A virus (VP1/P2A gene derived) fragment insertions. These size-distinguishable products were used as positive controls under the RT-PCR assay conditions used to detect NoV in stool and groundwater samples. Their reliability and reproducibility was confirmed by multiple sets of experiments. CONCLUSIONS: These standardized products may contribute to the reliable and accurate diagnosis by RT-PCR of norovirus outbreaks, when conducted by laboratories located in different regions.