Prevalence and relevance of the positivity of skin prick testing in patients with chronic urticaria

Many patients with chronic urticaria (CU) worry that foods or other allergens are responsible for their urticaria. Skin prick testing (SPT) may be one of the investigations used to provide a clear illustration. The purpose of our study was to assess the prevalence of positivity of SPT to food allergens and aeroallergens and their relevance in patients with CU, in order to demonstrate the diagnostic value of SPT in CU. We retrospectively reviewed case record forms of patients with chronic ordinary urticaria who underwent SPT in the Urticaria Clinic, Siriraj Hospital, during the period 2000-2004. The studied allergens included 16 food allergens and 12 aeroallergens. Eighty-eight patients were enrolled. The prevalence of positive SPT among patients with CU was 47.7%. Patients who had personal histories of atopy had statistically significant positive SPT results compared with patients who had negative SPT. Of 88 patients, 26 patients (30%) gave positive results to food allergens, 36 patients (41%) gave positive results to aeroallergens and 20 patients (22.7%) gave positive results to both food and aeroallergens. One-third of the subjects (34.6%) who had positive SPT results to food allergens had clinical relevance of food allergy in some systems but only one patient had clinical relevance of food-induced urticaria. Half of the patients who had a history of aeroallergen sensitivity gave a positive SPT response for aeroallergens; however, there was no clinical relevance to their CU. Our study showed that the prevalence of positive SPT to food allergens and aeroallergens in patients with CU was common but had little clinical relevance to CU.     

Molecular characterization of group A human rotaviruses in Bangkok and Buriram,Thailand during 2004–2006 reveals the predominance of G1P[8], G9P[8] and a rare G3P[19] strain

The aim of this study has been to determine the incidence of diverse human rotavirus strains circulating in Thailand between October 2004 and April 2006 by means of molecular characterization. Pediatric patients aged between 2 months and 5 years diagnosed with acute diarrhea (n = 307) in Bangkok and Buriram, Thailand were tested for human rotavirus A (RV-A) by RT-PCR. A total of 130 specimens (42.3%) were found RV-A positive and 126 were characterized by direct sequencing of the capsid glycoproteins VP7 and VP4. BLAST/FASTA analysis and phylogenetic analysis revealed genotypes G1P[8] (85.7%), G2P[4] (2.4%), G2P[8] (0.8%), G3P[8] (1.6%), G9P[8] (8.7%), and the uncommon strain G3P[19] (0.8%). Varying sites of polymorphism over time imply dependence on geographical location along with seasonal variation of relative incidence and distribution of rotavirus types. Thus, continuous molecular monitoring of human rotavirus epidemiology is essential for adjusting vaccine development.     

Genetic characterization of H1N1, H1N2 and H3N2 swine influenza virus in Thailand

Swine have been known to be a suitable host for influenza A virus. In Thailand, phylogenetic analysis on swine influenza virus (SIV) has as yet not been attempted. The present report presents molecular and phylogenetic analysis performed on SIV in Thailand. In this study, 12 SIV isolates from the central and eastern part of Thailand were subtyped and the molecular genetics of hemagglutinin and neuraminidase were elucidated. Three subtypes, H1N1, H1N2 and H3N2, are described. Phylogenetic analysis of the SIV hemagglutinin and neuraminidase genes shows individual clusters with swine, human or avian influenza virus at various global locations. Furthermore, amino acid substitutions were detected either at the receptor binding site or the antigenic sites of the hemagglutinin gene.     

Socio-demographic and environmental factors associated with Aedes breeding places in Phuket, Thailand

This study aimed to determine the socio-demographic and environmental factors influencing potential breeding sites of the dengue vector in Phuket Province. Three hundred houses were recruited by cluster random sampling for larval inspection. Of all the types of water containers, a high proportion of tires and discarded items were infested by Aedes larva (42% and 32%, respectively). Due to the abundance of water tanks, jars for using water and discarded containers (1.7, 2.1, 0.8 per house), these were the main breeding sites (0.29, 0.35, and 0.28 infested containers per house, respectively). Buddhists' houses were significantly more likely to have a larvae-infested flower vase than Muslims' houses. Townhouses had relatively few infested containers, while those on rubber plantations had 18.3 times higher odds of having at least one container with larva. No window screens increased the odds of larva infestation in the discarded containers by 4.2 times. With this information and given a reliable piped water supply, the number of water containers can be reduced to minimize the breeding places. Garbage should be properly disposed of. Screens should be installed, if possible. Buddhists should be advised on the proper protection of flower vases.     

Microtensile bond strength of a total-etching versus self-etching adhesive to caries-affected and intact dentin in primary teeth

BACKGROUND: The objec tives of this study were to determine microtensile bond strengths of two dentin adhesives and to compare the micromorphological structure of the resin/dentin interface in caries-affected dentin with that of intact dentin. METHODS: The authors randomly divided 40 proximal dentinal carious primary teeth and 40 noncarious anterior primary teeth into two groups (self-etching and total-etching). They used a caries-detecting dye as an indicator of the need to remove the outer carious dentin. The authors restored the teeth with a hybrid resin-based composite. After 24 hours' storage in 37 C water, specimens were sectioned and shaped to form a curved section with a cross-sectional area of 1 square millimeter, then tension was applied until they fractured. The authors prepared the resin/dentin interfaces for the two bonding systems and examined them in 10 occlusal carious and 10 noncarious teeth. STATISTICAL ANALYSIS: The bond strengths for intact and caries-affected dentin within the same group were analyzed via a t test. The authors compared the remaining dentin thickness (RDT) and dentin hardness using analysis of variance and the least significant difference test at the .05 level of significance. RESULTS: The self-etching adhesive demonstrated no statistical difference in bond strength between intact and caries-affected dentin. However, the total-etching adhesive demonstrated different bond strengths for intact and caries-affected dentin. Moreover, the RDT of specimens with intact and caries-affected dentin was not significantly different, whereas the dentin hardness of caries-affected dentin was significantly lower than that of intact dentin. The authors found a thicker hybrid layer in intact and caries-affected dentin of specimens in the total-etching group. CONCLUSION: The adhesives exhibited significantly different bond strengths in intact dentin of primary teeth. However, they exhibited similar bond strengths in caries-affected dentin.     

There is no association between K469E ICAM-1 gene polymorphism and biliary atresia

AIM: To determine whether there was an association between inter-cellular adhesion molecule-1 (ICAM-1) gene polymorphism and biliary atresia (BA), and to investigate the relationship between serum soluble ICAM-1 (sICAM-1) and clinical outcome in BA patients after surgical treatment. METHODS: Eighty-three BA patients and 115 normal controls were genotyped. K469E ICAM-1 polymorphism was analyzed using PCR assay. Serum sICAM-1 was determined using ELISA method from 72 BA patients. In order to evaluate the association between these variables and their clinical outcome, the patients were categorized into two groups: patients without jaundice and those with persistent jaundice. RESULTS: There were no significant differences between BA patients and controls in terms of gender, K469E ICAM-1 genotypes, and alleles. The proportion of patients having serum sICAM-1≥3 500 ng/mL in persistent jaundice group was significantly higher than that in the other group. In addition, there was no association between K469E ICAM-1 polymorphism and the status of jaundice in BA patients after Kasai operation. CONCLUSION: ICAM-1 possibly plays an important and active role in the disease progression. However, the process is not associated with genetic variation of K469E ICAM-1 polymorphism.