Scopus 2006-2010
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Publication Metadata only Duration of shedding of respiratory syncytial virus in a community study of Kenyan children(2010-01-22) Emelda A. Okiro; Lisa J. White; Mwanajuma Ngama; Patricia A. Cane; Graham F. Medley; D. James Nokes; Centre for Geographic Medicine Research; University of Oxford; Nuffield Department of Clinical Medicine; Mahidol University; Health Protection Agency; The University of WarwickBackground: Our understanding of the transmission dynamics of respiratory syncytial virus (RSV) infection will be better informed with improved data on the patterns of shedding in cases not limited only to hospital admissions.Methods: In a household study, children testing RSV positive by direct immunofluorescent antibody test (DFA) were enrolled. Nasal washings were scheduled right away, then every three days until day 14, every 7 days until day 28 and every 2 weeks until a maximum of 16 weeks, or until the first DFA negative RSV specimen. The relationship between host factors, illness severity and viral shedding was investigated using Cox regression methods.Results: From 151 families a total of 193 children were enrolled with a median age of 21 months (range 1-164 months), 10% infants and 46% male. The rate of recovery from infection was 0.22/person/day (95% CI 0.19-0.25) equivalent to a mean duration of shedding of 4.5 days (95%CI 4.0-5.3), with a median duration of shedding of 4 days (IQR 2-6, range 1-14). Children with a history of RSV infection had a 40% increased rate of recovery i.e. shorter duration of viral shedding (hazard ratio 1.4, 95% CI 1.01-1.86). The rate of cessation of shedding did not differ significantly between males and females, by severity of infection or by age.Conclusion: We provide evidence of a relationship between the duration of shedding and history of infection, which may have a bearing on the relative role of primary versus re-infections in RSV transmission in the community. © 2010 Okiro et al; licensee BioMed Central Ltd.Publication Metadata only Detection of Adverse Drug Reaction Signals in the Thai FDA Database: Comparison between Reporting Odds Ratio and Bayesian Confidence Propagation Neural Network Methods(2010-01-01) Waranee Bunchuailua; Ilene H. Zuckerman; Vithaya Kulsomboon; Wimon Suwankesawong; Pratap Singhasivanon; Jaranit Kaewkungwal; Silpakorn University; University of Maryland School of Pharmacy; The Food and Drug Administration, Thailand Ministry of Public Health; Mahidol UniversityThe study aimed to compare performance between the reporting odds ratio (ROR) and the Bayesian confidence propagation neural network (BCPNN) methods in identifying serious adverse drug reactions (ADRs) using the Thai FDA spontaneous database. The two methods were retrospectively applied to identify new, serious ADRs reported with antiretroviral therapy (ART) drugs using the data set between 1990 and 2006. We plotted the ROR and the information component against time to compare the differential timing of signal detection and the pattern of signaling over time between these methods. The ROR and the BCPNN methods identified the associations between ART drugs and serious ADRs at the same time. Both methods were similar in detecting the first signal of a potential ADR. However, the pattern of signaling seems relatively different with each method. Additional analyses of different drugs, ADRs, and databases will contribute to increase understanding of methods for postmarketing surveillance using spontaneous reporting system. © 2010, Drug Information Association. All rights reserved.Publication Metadata only Determination of pheniramine enantiomers in eye drop by capillary electrophoresis using hydroxypropyl-β-cyclodextrin as chiral selector(2010-07-01) K. Phatthiyaphaibun; W. Som-Aum; M. Srisa-Ard; J. Threeprom; Mahasarakham University; Mahidol UniversityA capillary zone electrophoresis procedure has been developed for the chiral determination of pheniramine in eye drop. Native and derivative cyclodextrins (CDs) including γ-CD, β-CD, hydroxypropyl-β-CD and dimethyl-β-CD were tested as chiral selectors. Using 30 mM hydroxypropyl-β-CD in 50 mM phosphate buffer (pH 3.0), the acceptable resolution value (R = 1.55) was obtained. The assay was validated for linearity (3.3 × 10-6-5.0 × 10-4M; R2= 0.9996), limit of detection (3.3 × 10-6M), limit of quantification (8.5 × 10-6M), analytical precision by terms of intra- and inter-day variability (RSD ≤ 2.57%), and accuracy (recovery ≥ 89.3%). The content of pheniramine in eye drop obtained by the proposed method was in good agreement with the declared value. The results indicated that pheniramine in the eye drop was present as the racemate. © 2010 Pleiades Publishing, Ltd.Publication Metadata only Efficacy and Safety of Oral Propranolol Premedication to Reduce Reflex Tachycardia During Hypotensive Anesthesia With Sodium Nitroprusside in Orthognathic Surgery: A Double-Blind Randomized Clinical Trial(2010-01-01) Benjamas Apipan; Duangdee Rummasak; Mahidol UniversityPurpose: The present study sought to determine whether premedication with oral propranolol 10 mg before hypotensive anesthesia with sodium nitroprusside could reduce reflex tachycardia, the amount of sodium nitroprusside used, and blood loss during hypotensive anesthesia for orthognathic surgery. Patients and Methods: A total of 60 patients undergoing bimaxillary surgery were studied in a prospective, randomized, and double-blind study of oral propranolol 10 mg or placebo as premedication before hypotensive anesthesia with sodium nitroprusside. Hemodynamic variables, the amount of sodium nitroprusside used, and blood loss were statistically analyzed. Results: The heart rate and amount of sodium nitroprusside used were highly significantly less (P < .01) in the propranolol group, but no significant difference was found in blood loss between the 2 groups. No clinically significant complications were observed in either group. Conclusion: Premedication with oral propranolol 10 mg before hypotensive anesthesia with sodium nitroprusside is safe and effective to reduce reflex tachycardia and the amount of sodium nitroprusside used. © 2010 American Association of Oral and Maxillofacial Surgeons.Publication Metadata only Alteration in the expression of cdk4 and cdk6 proteins in oral cancer and premalignant lesions(2010-11-01) Sopee Poomsawat; Waranun Buajeeb; Siribang on Khovidhunkit; Jirapa Punyasingh; Mahidol UniversityBackground: Cdk4 and cdk6, key players in G1 phase, have been shown to play an important role in the development of oral squamous cell carcinoma (OSCC). This study investigated the expression of these two proteins in OSCC and premalignant lesions including oral leukoplakia (OL) with and without dysplasia and determined if alterations in the expression of these two proteins could be used as markers of malignant transformation.Methods: Expressions of cdk4 and cdk6 were evaluated in 61 samples including OSCC, OL with and without dysplasia and normal oral mucosa using immunohistochemistry method. Nuclear staining of the keratinocytes was considered positive and the percentage of positive cells was calculated.Results: Expression of cdk4 was found in 11/15 (73.33%) OSCC, 13/14 (92.85%) OL with dysplasia, 13/20 (65%) OL without dysplasia and 3/12 (25%) normal mucosa. Expression of cdk6 was detected in 9/15 (60%) OSCC, 3/14 (21.43%) OL with dysplasia, 5/20 (25%) OL without dysplasia and 1/12 (8.33%) normal mucosa. In cdk4 stained specimens, the frequency of positive cases and the percentage of positive cells in normal mucosa was significantly lower than OL with dysplasia and OSCC. For cdk6 staining, the prevalence of positive cases and the percentage of positive cells in normal mucosa were significantly lower than OSCC.Conclusions: Overexpressions of cdk4 and cdk6 were observed in OSCC, indicating that these two proteins play a crucial role in OSCC. The aberrant expression of cdk4 was found in OL with dysplasia, suggesting that cdk4 may be involved in the early event of carcinogenesis. © 2010 John Wiley & Sons A/S.Publication Metadata only Existence of a blow-up solution for a degenerate parabolic initial-boundary value problem(2010-12-01) P. Sawangtong; W. Jumpen; King Mongkut's University of Technology North Bangkok; Mahidol University; Centre of Excellence in Mathematics CHEHere, before blow-up occurs, we establish the existence and uniqueness of a blow-up solution of a degenerate parabolic initial-boundary value problem,xqut-(xβux) x=xq(u) where q and β are given constants and f is a suitable function. We further give the sufficient condition to blow-up in finite time. Finally the blow-up set of a blow-up solution u is shown.Publication Metadata only Application of mobile-technology for disease and treatment monitoring of malaria in the "Better Border Healthcare Programme"(2010-08-23) Pongthep Meankaew; Jaranit Kaewkungwal; Amnat Khamsiriwatchara; Podjadeach Khunthong; Pratap Singhasivanon; Wichai Satimai; Mahidol University; Thailand Ministry of Public HealthBackground: The main objective of this study was to assess the effectiveness of integrating the use of cell-phones into a routine malaria prevention and control programme, to improve the management of malaria cases among an under-served population in a border area. The module for disease and treatment monitoring of malaria (DTMM) consisted of case investigation and case follow-up for treatment compliance and patients' symptoms. Methods: The module combining web-based and mobile technologies was developed as a proof of concept, in an attempt to replace the existing manual, paper-based activities that malaria staff used in treating and caring for malaria patients in the villages for which they were responsible. After a patient was detected and registered onto the system, case-investigation and treatment details were recorded into the malaria database. A follow-up schedule was generated, and the patient's status was updated when the malaria staff conducted their routine home visits, using mobile phones loaded with the follow-up application module. The module also generated text and graph messages for a summary of malaria cases and basic statistics, and automatically fed to predetermined malaria personnel for situation analysis. Following standard public-health practices, access to the patient database was strictly limited to authorized personnel in charge of patient case management. Results: The DTMM module was developed and implemented at the trial site in late November 2008, and was fully functioning in 2009. The system captured 534 malaria patients in 2009. Compared to paper-based data in 2004-2008, the mobile-phone-based case follow-up rates by malaria staff improved significantly. The follow-up rates for both Thai and migrant patients were about 94-99% on Day 7 (Plasmodium falciparum) and Day 14 (Plasmodium vivax) and maintained at 84-93% on Day 90. Adherence to anti-malarial drug therapy, based on self-reporting, showed high completion rate for P. falciparum-infected cases, but lower rate for P. vivax cases. Patients' symptoms were captured onto the mobile phone during each follow-up visit, either during the home visit or at Malaria Clinic; most patients had headache, muscle pain, and fatigue, and some had fever within the first follow-up day (day7/14) after the first anti-malarial drug dose. Conclusions: The module was successfully integrated and functioned as part of the malaria prevention and control programme. Despite the bias inherent in sensitizing malaria workers to perform active case follow-up using the mobile device, the study proved for its feasibility and the extent to which community healthcare personnel in the low resource settings could potentially utilize it efficiently to perform routine duties, even in remote areas. The DTMM has been modified and is currently functioning in seven provinces in a project supported by the WHO and the Bill & Melinda Gates Foundation, to contain multi-drug resistant malaria on the Thai-Cambodian border. © 2010 Meankaew et al; licensee BioMed Central Ltd.Publication Metadata only Weibull analysis of bond strength of orthodontic buccal tubes bonded to resin composite surface with various techniques(2010-06-01) Nita Viwattanatipa; Walaitip Jermwiwatkul; Rochaya Chintavalakorn; Widchaya Kanchanavasita; Mahidol UniversityThe objective of this study was to analyze the survival probabilities of various surface preparation techniques for bonding buccal tubes on resin composite surface. Resin composite specimens (hybrid), 33 per group were prepared. 8 experimental groups were (1) sandblast 90 μm; (2) sandblast 50 μm; (3) abrasion using diamond bur; (4) hydrofluoric acid etching for 1 min (HF 1 min); (5) HF 2 min; (6) HF 3 min; (7) 37% orthophosphoric etching for 10 min (H3PO410 min) and (8) control (unetched surface). Plastic conditioner was applied then buccal tubes were bonded. Shear bond strength was tested with the universal testing machine and the Weibull analysis was performed. The results at a stress level of 7.8 MPa and 10 MPa, revealed the probabilities of survival for sandblast 50 μm (100%, 99.9%), sandblast 90 μm (99.7%, 98.7%), diamond bur (98.3%, 93.4%), HF 2 min (95.9%, 85.3%), HF 1 min (78.3%, 61.4%), HF 3 min (70.6%, 46.3%), H3PO410 min (61.4%, 44.5%) and control (26.3%, 6.9%), respectively. Therefore, surface preparation by sandblast (50 μm and 90 μm), or diamond bur followed by plastic conditioner were highly effective for bonding orthodontic buccal tubes on hybrid resin composite surface. HF 2 min was acceptable. However, HF 1 min, 3 min, H3PO4etching and unetched surface could not achieve adequate bond survival. © 2010 Elsevier Ltd and the Japanese Orthodontic Society.Publication Metadata only Discordant influence of Blastomyces dermatitidis yeast-phase-specific gene BYS1 on morphogenesis and virulence(2010-06-01) Theerapong Krajaejun; Marcel Wüthrich; Gregory M. Gauthier; Thomas F. Warner; Thomas D. Sullivan; Bruce S. Klein; University of Wisconsin School of Medicine and Public Health; Mahidol UniversityBlastomyces dermatitidis is a thermally induced dimorphic fungus capable of causing lung and systemic infections in immunocompetent animal hosts. With the publication of genomic sequences from three different strains of B. dermatitidis and the development of RNA interference as a gene-silencing tool, it has become possible to easily ascertain the virulence and morphological effects of knocking down the expression of candidate genes of interest. BYS1 (Blastomyces yeast-phase-specific 1), first identified by Burg and Smith, is expressed at high levels in yeast cells and is undetectable in mold. The deduced protein sequence of BYS1 has a putative signal sequence at its N terminus, opening the possibility that the BYS1-encoded protein is associated with the yeast cell wall. Herein, strains of B. dermatitidis with silenced expression of BYS1 were engineered and tested for morphology and virulence. The silenced strains produced rough-surfaced cultures on agar medium and demonstrated a propensity to form pseudohyphal cells on prolonged culture in vitro and in vivo, as measured in the mouse lung. Tests using a mouse model of blastomycosis with either yeast or spore inocula showed that the bys1-silenced strains were as virulent as control strains. Thus, although silencing of BYS1 alters morphology at 37°C, it does not appear to impair the pathogenicity of B. dermatitidis. Copyright © 2010, American Society for Microbiology. All Rights Reserved.Publication Metadata only Acute appendicitis as primary symptom of prostatic adenocarcinoma: Report of a case(2010-11-01) Samrerng Ratanarapee; Chaiyong Nualyong; Mahidol UniversityThe most common disease of appendix is acute appendicitis. There have been at least 20 case reports of metastasisinduced appendicitis in English literature. The authors reported a 62-year-old Thai man who underwent appendectomy due to classical symptoms and signs of acute appendicitis and was subsequently referred to Siriraj Hospital for proper management after a pathological report of metastatic adenocarcinoma to the appendix. By morphology, the primary site was thought to be the prostate gland. Confirmation was done based on serum PSA study, transrectal ultrasound-guided core needle biopsy, and review of the material from Hua Hin Hospital. Orchidectomy was performed with satisfactory outcome. The patient was doing well for two years before upper gastrointestinal hemorrhage and obstructive jaundice caused by another aggressive tumor developed. He died of the second tumor associated with subsequent renal failure in spite of good response to orchidectomy.Publication Metadata only Withering syndrome in the abalone Haliotis diversicolor supertexta(2010-05-18) Thanitsara Wetchateng; Carolyn S. Friedman; Nathan A. Wight; Pei Yu Lee; Ping Hua Teng; Siriporn Sriurairattana; Kanokphan Wongprasert; Boonsirm Withyachumnarnkul; Mahidol University; University of Washington, Seattle; Central Taiwan University of Science and TechnologyAbalone aquaculture is a small but growing industry in Thailand and is based on both the exotic Haliotis diversicolor supertexta and the native H. asinina. Withering syndrome (WS) in abalone is caused by an infection with the Rickettsia-like organism (RLO) 'Candidatus Xenohaliotis californiensis' and has been spread to many countries globally. The present study reports the first observation of the WS-RLO agent in the small abalone, H. diversicolor supertexta in Thailand, Taiwan (ROC) and the People's Republic of China (PRC). Under light microscopy, the RLO was observed as intracytoplasmic inclusions within epithelial cells lining the post-esophagus and, to a minor extent, the intestine of H. diversicolor. Under transmission electron microscopy, inclusions were characterized as colonies of rod-shaped bacteria, 200 × 1800 nm in size, within a vesicle in the cytoplasm of the infected cell. The RLO from the small abalone bound with WS-RLO-specific in situ hybridization probes and was amplified by polymerase chain reaction (PCR), using primers designed from the 16S rDNA sequence of the original WS-RLO from California, USA. The PCR product of RLO samples from both the PRC and Thailand showed extremely high identity with the California WS-RLO (100 and 99%, respectively). These data combined with the history of abalone movements for aquaculture purposes indicate that RLOs observed in Thailand, Taiwan and the PRC are the WS-RLO that originated from California. © Inter-Research 2010.Publication Metadata only Fingerprint recognition by euclidean distance(2010-07-12) Chomtip Pornpanomchai; Apiradee Phaisitkulwiwat; Mahidol UniversityThis research proposed the fingerprint recognition by euclidean distance method. the system uses a technique of image processing, which consists of 3 major components, which are: 1) preprocessing component, the module that reduces the noise of the original images and adjusts the sharpness of the lined pattern that is the components of the fingerprint, 2) feature extraction component, the module that defines the position of the core point used as a reference point and finds out the position of the bifurcation points, and 3) fingerprint recognition component, the module to compare the shape context of training and testing data sets. based on the experimental results, the system has acceptable accuracy with average access time of around 19.68 seconds per image. © 2010 IEEE.Publication Metadata only Antioxidant activity and lipid-lowering effect of essential oils extracted from Ocimum sanctum L. leaves in rats fed with a high cholesterol diet(2010-01-01) Thamolwan Suanarunsawat; Watcharaporn Devakul Na Ayutthaya; Thanapat Songsak; Suwan Thirawarapan; Somlak Poungshompoo; Rangsit University; Mahidol University; Chulalongkorn UniversityIt has been reported that Ocimum sanctum L. (OS) leaves decrease serum lipid profile in normal and diabetic animals. No experimental evidences support the anti-hyperlipidemic and antioxidative actions against hypercholesterolemia. Moreover the identity of the specific chemical ingredients in OS leaves responsible for these pharmacological effects are unknown. Since OS leaves are rich in essential oil (EO). Therefore the present study was conducted to investigate the anti-hyperlipidemic and antioxidative activities of EO extracted from OS leaves in rats fed with high cholesterol (HC) diet. EO was extracted by the hydrodistillation method and the chemical constituents were then identified by Gas Chromatography-Mass Spectrometry. The experiment was performed in Male Wistar rats fed with 2.5 g%(w/w) of cholesterol diet for seven weeks. During the last 3 weeks, rats were daily fed with EO. The results showed that phenyl propanoid compounds including eugenol and methyl eugenol were the major constituents of EO. EO suppressed the high serum lipid profile and atherogenic index as well as serum lactate dehydrogenase and creatine kinase MB subunit without significant effect on high serum levels of aspartate aminotransferase, alanine amino-transferase and alkaline phosphatase in rats fed with HC diet. In addition, EO was found to decrease the high levels of thiobarbituric acid reactive substances (TBARS), glutathione peroxidase (GPx) and superoxide dismutase (SOD) without impacting catalase (CAT) in the cardiac tissue while in the liver, it decreased high level of TBARS without significantly effecting GPx, SOD and CAT. Histopathological results confirmed that EO preserved the myocardial tissue. It can be concluded that EO extracted from OS leaves has lipid-lowering and antioxidative effects that protect the heart against hypercholesterolemia. Eugenol that is contained in EO likely contribute to these pharmacological effects.Publication Metadata only A novel method to derive amniotic fluid stem cells for therapeutic purposes(2010-10-19) Tatsanee Phermthai; Yuparat Odglun; Suphakde Julavijitphong; Vitaya Titapant; Prakong Chuenwattana; Chanchai Vantanasiri; Kovit Pattanapanyasat; Mahidol UniversityBackground: Human amniotic fluid stem (hAFS) cells have become an attractive stem cell source for medical therapy due to both their ability to propagate as stem cells and the lack of ethical debate that comes with the use of embryonic stem cells. Although techniques to derive stem cells from amniotic fluid are available, the techniques have limitations for clinical uses, including a requirement of long periods of time for stem cell production, population heterogeneity and xeno-contamination from using animal antibody-coated magnetic beads. Herein we describe a novel isolation method that fits for hAFS derivation for cell-based therapy.Methods and Results: With our method, single hAFS cells generate colonies in a primary culture of amniotic fluid cells. Individual hAFS colonies are then expanded by subculturing in order to make a clonal hAFS cell line. This method allows derivation of a substantial amount of a pure stem cell population within a short period of time. Indeed, 108 cells from a clonal hAFS line can be derived in two weeks using our method, while previous techniques require two months. The resultant hAFS cells show a 2-5 times greater proliferative ability than with previous techniques and a population doubling time of 0.8 days. The hAFS cells exhibit typical hAFS cell characteristics including the ability to differentiate into adipogenic-, osteogenic- and neurogenic lineages, expression of specific stem cell markers including Oct4, SSEA4, CD29, CD44, CD73, CD90, CD105 and CD133, and maintenance of a normal karyotype over long culture periods.Conclusions: We have created a novel hAFS cell derivation method that can produce a vast amount of high quality stem cells within a short period of time. Our technique makes possibility for providing autogenic fetal stem cells and allogeneic cells for future cell-based therapy. © 2010 Phermthai et al; licensee BioMed Central Ltd.Publication Metadata only Synthesis and characterizations of PLLA/PEG block copolymers(2010-02-05) Thai Hien Nguyen; Atitsa Petchsuk; Pramuan Tangboriboonrat; Mantana Opaprakasit; Alice Sharp; Pakorn Opaprakasit; Sirindhorn International Institute of Technology, Thammasat University; Thailand National Metal and Materials Technology Center; Mahidol University; Chulalongkorn UniversityPoly(lactic acid-co-ethylene glycol) (PLLA/PEG) copolymers were synthesized and their properties were characterized. The PLLA/PEG/PLLA triblock copolymers were synthesized by ring-opening polymerization from l-lactide (LLA) and PEG macroinitiator. Stannous octoate, Sn(Oct)2was used as a catalyst. Effects of molecular weight of PEG (600, 2000 and 4000), LLA/OH molar ratios (95:5, 98:2) and a sequence of addition of the reactants on properties of the copolymers were investigated. The triblock copolymers were subsequently used in a production of multiblock copolymers by reacting with a chain-extending agent, hexamethylene diisocyanate (HMDI). Chemical structure and molecular weight of the copolymers were characterized by1HNMR, FTIR and GPC. The results showed that molecular weight of triblock copolymers varied from 4,500 to 10,200. After chain extension, multiblock copolymer with molecular weight of 16,490 was produced. Thermal properties of the copolymers were also examined by DSC. © (2010) Trans Tech Publications.Publication Metadata only Changes in the mRNA expression of osteoblast-related genes in response to β3-adrenergic agonist in UMR106 cells(2010-01-01) Amporn Nuntapornsak; Kannikar Wongdee; Jirawan Thongbunchoo; Nateetip Krishnamra; Narattaphol Charoenphandhu; Mahidol University; Burapha UniversityActivation of adrenergic receptors (AR) was demonstrated to result in either bone gain or bone loss depending on the activated AR subtypes and concentrations of agonists used. While β2-AR agonist was extensively investigated as an osteopenic agent, effects of β3-AR activation on osteoblasts were still elusive. Rat osteoblast-like UMR106 cells were herein found to express several AR subtypes, including β3-AR. After exposure to a low-dose β3-AR agonist BRL37344 (10 nmol L-1), UMR106 cells downregulated the mRNA expression of transcription factors Runx2 and Dlx5, which are important for initiation of osteoblast differentiation. Low-dose BRL37344 also decreased the expression ratio of receptor activator of nuclear factor kB ligand (RANKL) over osteoprotegerin (OPG), suggesting the protective effect of β3-AR agonist against bone resorption. Alkaline phosphatase expression was markedly decreased, whereas expressions of osteocalcin and osteopontin were increased by 100 nmol L-1 BRL37344, indicating that β3-AR activation could accelerate the transition of matrix maturation stage to mineralization stage. In conclusion, b3-AR activation in rat osteoblasts induced alteration in the expression of osteoblast-related transcription factor genes as well as genes required for bone formation and resorption. The present results also suggest that, besides β2-AR, β3-AR is another AR subtype responsible for the sympathetic nervous system-induced bone remodeling. Copyright © 2009 John Wiley & Sons, Ltd.Publication Metadata only Giardia intestinalis in Thailand: Identification of genotypes(2010-02-01) Anchalee Tungtrongchitr; Nitat Sookrung; Nitaya Indrawattana; Sukanya Kwangsi; Jeerawan Ongrotchanakun; Wanpen Chaicumpa; Mahidol UniversityThis study was undertaken to determine the genetic diversities of Giardia intestinalis isolated in Thailand. G. intestinalis cysts were collected from stool samples of 61 subjects residing in Bangkok or in rural communities of Thailand with and without gastrointestinal symptoms. All the cyst samples gave positive tpi amplicons (100% sensitivity), either of the 148-or the 81-bp tpi segments. Cyst assemblage identification of the 148- and 81-bp tpi gene segments by polymerase chain reaction showed that 8% of the cysts were assemblage A, 41% assemblage A and B combined, and 51% assemblage B. The prevalence of assemblage A was significantly lower than that of assemblage B and the mixed types. Restriction fragment length polymorphism (RFLP) of the 384-bp ß-giardin gene segment revealed that 12% and 88% of the assemblage A cysts were AI and AII respectively. RFLP, based on the 432-bp gdh gene segment, showed 45.5% of the assemblage B cysts to be BIII and 54.5% to be BIV. The AI sub-assemblage was less prevalent than the others. All subjects with AI and 50% of the subjects with BIII sub-assemblage cysts were symptomatic; 80% of symptomatic Bangkok residents were adults/elderly while 85% of the rural cases were children. © International Centre for Diarrhoeal Disease Research, Bangladesh.Publication Metadata only Formulation development of morphine sulfate sustained-release tablets and its bioequivalence study in healthy thai volunteers(2010-09-01) Detpon Preechagoon; Viroj Sumyai; Suvatna Chulavatnatol; Poj Kulvanich; Thanee Tessiri; Khanittha Tontisirin; Thaned Pongjanyakul; Verawan Uchaipichat; Sirikul Aumpon; Chaiyasit Wongvipaporn; Khon Kaen University; The Food and Drug Administration, Thailand Ministry of Public Health; Mahidol University; Chulalongkorn UniversityThe objectives of this study were to develop morphine sulfate sustained-release tablet formulations and to evaluate the bioequivalence compared with a commercial brand. The physicochemical properties of the formulated and commercial tablets were determined and compared. The bioequivalence investigation was carried out in 15 healthy male volunteers who received a single dose in a randomized two-way crossover design. After dosing, serial blood samples were collected for a period of 24 h. Morphine concentration was assayed by high-performance liquid chromatography with electrochemical detector. The log-transformed Cmaxand AUCswere statistically compared by analysis of variance, and the 90% confidence intervals (CIs) of the ratio of the log-transformed Cmaxand AUCsbetween the most promising developed formulation and the commercial product were determined. It was found that the dissolution rate profile of a developed formulation was similar to the commercial brand. Their similarity and difference factors were well within limits. In the bioequivalence study, the AUClastand AUCinfbetween the test and the reference products were not statistically different (p=0.227 and p=0.468, respectively), with the 90% CIs of 83.4-102.6% and 87.7-139.4%, respectively. However, the Cmaxof the two formulations was significantly different (p=0.019). The 90% CI of the developed formulation was 72.0-93.0% compared to the commercial product. In vitro dissolution of locally prepared morphine sulfate sustained-release tablets was comparable to commercial brand. However, the results justified the conclusion of lack of bioequivalence of the developed product to the commercial one. © 2010 American Association of Pharmaceutical Scientists.Publication Metadata only Endoscopic treatment of acute Ascaris pancreatitis(2010-01-25) S. Leelakusolvong; T. Sriprayoon; A. Methasate; T. Akaraviputh; Mahidol UniversityPublication Metadata only Magneto transport on the surface of a topological insulator spin valve(2010-06-21) Bumned Soodchomshom; Mahidol University; Commission on Higher EducationThe effects of the magnetization on the transport properties of a ferromagnet/barrier/ferromagnet spin valve fabricated with a topological insulator are studied. We consider two types of junctions, (i) an F1 / normal barrier (NB) / F2 junction and (ii) an F1 / magnetic barrier (FB) / F2 junction. The junctions in both cases lie in the xy-plane with the magnetizations in both ferromagnetic regions, F1 and F2 aligned in the z-direction. The charge carriers in the topological insulator have a Dirac like energy spectrum of a massive relativistic particle with the magnetization M playing the role of the mass. The gap opening is a special magneto feature of topological insulators. In an anti parallel alignment of the two magnetizations, the mass of the carriers is negative in the region where M is in the negative direction. The negative mass leads the behaviors of the magneto transport properties and the tunneling magneto resistance of these junctions to be quite different from those of graphene-based spin values. © 2010 Elsevier B.V. All rights reserved.