Scopus 1991-2000
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Publication Metadata only Serum tissue polypeptide specific antigen (TPS) in locoregional failure and distant metastasis of cervical carcinoma(2000-09-01) Pittayapoom Pattaranutaporn; Nantakan Ieumwananonthachai; Yaowalak Chansilpa; Mathuros Sukkasem; Mahidol UniversityTissue polypeptide specific antigen (TPS) was measured by the ELISA Technique in the sera of 51 patients with locoregional failure and metastasis of squamous cell carcinoma of the cervix in order to evaluate the serum level of TPS in known cases of metastasis and recurrence. There were 32 cases of local residual or recurrent disease and 19 cases of distant metastasis, including lymph nodes (paraaortic and supraclavicular lymph node) and visceral metastasis. The range of TPS levels in the locoregional failure group were 38.2 - 355.2 μ/l with a mean of 312.5 and 35.7 - 4822 μ/l with a mean of 833.36 μ/l in the metastatic group. With the cut-off value of 90 μ/l, the rates of TPS elevation were 27 in 32 cases (84.37%) of the loco-regional failure group and 16 in 19 cases (84.21%) of the metastatic group. Among the metastatic group, the mean of TPS level in visceral metastasis was much higher than the group of lymph node metastasis (1518.4 μ/l vs 215.1 μ/l). TPS level might be used as the follow-up guide for prediction of locoregional failure and metastasis in squamous cell carcinoma of the cervix after the completion of the treatment. In patients with a significantly high level of serum TPS, the distant metastases or local recurrence should be searched for. However, a prospective study of TPS levels in cervical cancer patients after completion of treatment should be done in order to evaluate the sensitivity and specificity of this tumor marker.Publication Metadata only High expression of the penicillin G acylase gene (pac) from Bacillus megaterium UN1 in its own pac minus mutant(2000-08-15) W. Panbangred; K. Weeradechapon; S. Udomvaraphant; K. Fujiyama; V. Meevootisom; Mahidol University; Osaka UniversityBy marker exchange mutagenesis, Bacillus megaterium strain UN-1 (Bm-UN1) was used to prepare a mutant strain B. megaterium UN-cat (Bm-UNcat) lacking the penicillin G acylase gene (pac). The pac gene from Bm-UN1 was subcloned into pTF6 and the resultant plasmid, pBA402, was introduced into Bm-UNcat and Bacillus subtilis. Bm-UNcat harbouring pBA402 produced high penicillin G acylase (PAC) activity of 13.7, 19.5 and 20.4 U ml1 at 24, 36 and 48 h of culture, respectively. This was two- to fivefold higher than PAC produced by B. subtilis harbouring pBA402 and about 20-fold higher than PAC produced by the parent strain, Bm-UN1.Publication Metadata only A flow cytometric method for measuring neutralization of HIV-1 subtype B and E primary isolates(2000-06-01) Janice M. Darden; Victoria R. Polonis; Mark S. DeSouza; Somsak Chantakulkij; Arthur E. Brown; Deborah L. Birx; Kovit Pattanapanyasat; Mahidol University; Armed Forces Research Institute of Medical Sciences, Thailand; Walter Reed Army Institute of Research; Faculty of Medicine, Siriraj Hospital, Mahidol UniversityBackground: Clinical trials testing candidate human immunodeficiency virus type 1 (HIV-1) vaccines have required the use of HIV neutralization assays to detect responses to specific geographic subtypes of HIV-1. The variability in results seen with current p24 neutralization assay endpoints prompted us to assess the utility of flow cytometry for monitoring the neutralization of HIV-1 primary isolates. Methods: A modified neutralization assay was performed using CD8-depleted peripheral blood mononuclear cells (PBMC). The cells were fixed, permeabilized, stained with a directly conjugated HIV-1 p24 monoclonal antibody, and analyzed by flow cytometry. HIV-1 subtype B' and E primary isolates were tested using pooled sera or plasma from subtype B' or E infected patients. Results: Primary isolate cultures (without neutralizing antibody) showed from 18% to 42% p24+ cells, depending on the virus. Less than 0.2% p24+ cells were detected in uninfected cultures. Subtype-specific neutralization of viruses was observed using plasma or serum pools; neutralization ranged from 0% to 99% reduction of infected cells. Conclusions: Flow cytometric detection of intracellular HIV-1 p24 can be used as an endpoint assay to assess neutralization of HIV-1 subtypes B' and E primary isolates. This enumerative method has the advantage of identifying intracellular p24 in specific subsets at an early culture timepoint. It also provides an alternative quantitative end-point for HIV neutralization assays. (C) 2000 Wiley-Liss, Inc.Publication Metadata only Indomethacin prophylaxis for patent ductus arteriosus (PDA) in infants with a birth weight of less than 1250 grams(1999-01-01) Sarayut Supapannachart; Pongsak Khowsathit; Benjawan Patchakapati; Mahidol UniversityBackground : Very low birth weight (VLBW, less than 1500 g) and extremely low birth weight infants (ELBW, less than 1000 g) are the premature infants that are most likely to develop symptomatic PDA. Intravenous indomethacin has proven effective in prevention of PDA in many prospective trials. This strategy will be a useful adjunctive therapy for premature infants in Thailand. Objective : To answer the following questions: 1. Will multiple doses of intravenous indomethacin, given to VLBW infants within the first day of life; effectively prevent the occurrence of symptomatic PDA? Are there any side effects or complications? 2. Will this strategy be more beneficial in ELBW? Methods and subjects : The study included thirty VLBW infants born at Ramathibodi Hospital, with birth weights ranging from 630 to 1230 g. They were randomized into 2 groups of 15 infants each. One group received 3 doses of intravenous indomethacin at the dosage of 0.2 mg/kg initially and then 0.1 mg/kg every 12 hours for 2 more-doses; the second group received a placebo. The study was performed by a double blind control. Results : Sixteen infants developed symptomatic PDA, 4 in the indomethacin group and 12 in the placebo group. The decrease in incidence of PDA is statistically significant. But when the data was analyzed separately for the VLBW and ELBW groups. The effects were only significantly different in ELBW but not yet significant in the VLBW group. There was a statistically significant difference in the incidence of severe intraventricular hemorrhage (IVH) (grade 3 or higher) in the ELBW infants. Conclusion : Intravenous indomethacin therapy given to VLBW infants with a birth weight of less than 1250 g decreased incidence of symptomatic PDA with no significant permanent side effects. The effect was markedly noticable in ELBW infants. Incidence of severe IVH was also markedly decreased in the ELBW infants who received indomethacin.Publication Metadata only Levels of plasma lipid peroxide products and antioxidant status in rheumatoid arthritis(2000-06-01) Saowanee Kajanachumpol; Monchand Vanichapuntu; Oravan Verasertniyom; Kitti Totemchokchyakarn; Mongkol Vatanasuk; Mahidol UniversityOxygen free radicals have been implicated as mediators of tissue damage in patients with rheumatoid arthritis. The aim of our study was to assess the lipid peroxide products and antioxidant status in rheumatoid arthritis patients (RA). The study involved determination of two plasma lipid peroxide products, malondialdehyde (MDA) and conjugated dienes (CD), two plasma antioxidant vitamins (C and E) in 91 RA patients and 26 healthy subjects. The results showed that rheumatoid patients had increased plasma CD but not MDA and decreased plasma vitamin E, when properly expressed per unit cholesterol and triglyceride. This finding suggested that RA patients had increased oxidant stress that might play a role in the tissue damage and inflammation process of this disease.Publication Metadata only Delaying antimalarial drug resistance with combination chemotherapy.(1999-09-01) N. J. White; Mahidol UniversityResistance to antimalarial drugs arises when spontaneously occurring mutants with gene mutations or amplifications which confer reduced drug susceptibility are selected, and are then transmitted. Simultaneous use of two or more antimalarials with different modes of action and which therefore do not share the same resistance mechanisms will reduce the chance of selection, because the chance of a resistant mutant surviving is the product of the parasite mutation rates for the individual drugs, multiplied by the number of parasites in an infection that are exposed to the drugs. The artemisinin derivatives are very active antimalarials, which produce large reductions in parasite biomass per asexual cycle, and reduce malaria transmissibility. To date no resistance to these drugs has been reported. These drugs therefore make particularly effective combination partners. This suggests that antimalarial drugs should not be used alone in treatment, but always in combination, as in the treatment of tuberculosis or HIV, and that the combination should include artemisinin or one of its derivatives.Publication Metadata only New cytotoxic 1-azaanthraquinones and 3-aminonaphthoquinone from the stem bark of Goniothalamus mareanii(1999-10-01) Noppamas Soonthornchareonnon; Khanit Suwanborirux; Rapepol Bavovada; Chamnan Patarapanich; John M. Cassady; Chulalongkorn University; Ohio State University; Mahidol UniversityGuided by brine shrimp toxicity and human tumor cell toxicity, fractionation of the alcoholic extract from the stem bark of Goniothalamus marcanii led to the isolation of four new 1-azaanthraquinones: marcanines B (3), C (4), D (5), and E (6), along with two known derivatives: marcanine A and dielsiquinone. A new 5-hydroxy-3-amino-2-aceto-1,4-naphthoquinone (7), a possible 1-azaanthraquinone biosynthetic precursor, was also isolated. The structures of the compounds were elucidated by spectroscopic analyses, mainly 1D and 2D NMR techniques (1H, 13C, NOEDS, COSY, HMQC, and HMBC), as well as comparison with literature data. All the compounds except 6 were evaluated for cytotoxic activity. They exhibited significant cytotoxicity against several human tumor cell lines, A-549, HT-29, MCF7, RPMI, and U251 with the ED50 in the range of 0.04-3.03 μM.Publication Metadata only IgE deposition in brain microvessels and on parasitized erythrocytes from cerebral malaria patients(2000-01-01) Yoshimasa Maeno; Peter Perlmann; Hedvig Perlmann; Yasuhiro Kusuhara; Koki Taniguchi; Toshio Nakabayashi; Kyaw Win; Sornchai Looareesuwan; Masamichi Aikawa; Tokai University; Fujita Health University School of Medicine; Mahidol University; Department of Molecular Biosciences, The Wenner-Gren Institute; Embassy of the Union of Myanmar; Fujita Health UniversityPostmortem brain tissues of 21 cerebral malaria cases were obtained in Myanmar and Vietnam. The tissues were examined Dy light microscopy and by an immunohistochemical method. Brain microvessels (capillaries and venules) were examined for the presence of immunoglobulins IgE and IgG, Plasmodium falciparum antigen, and parasitized erythrocytes (PRBC). Deposition of IgE, IgG, and P. falciparum antigen was observed in the microvessels from all specimens examined. Sequestered PRBC in the microvessels were positive for IgG in all 21 cases and for IgE in six cases. In the latter cases, the percentage of microvessels with sequestered PRBC was > 50%, with the frequency of IgE-positive cells ranging from 42% to 52%. In contrast, in five cases that were only weakly positive for IgE, the percentage of microvessels with sequestered PRBC was remarkably low (< 1%). These data indicate that the degree of deposition of IgE in microvessels and on PRBC from cerebral malaria patients correlated with that of PRBC sequestration. As IgE-containing immune complexes are known to induce local overproduction of tumor necrosis factor-alpha (TNF-α), a major pathogenic factor in cerebral malaria, IgE may contribute to the pathogenesis of this severe disease.Publication Metadata only The changing pattern of head injury in Thailand(2000-01-01) Nakornchai Phuenpathom; Montip Tiensuwan; Sanguansin Ratanalert; Sakchai Saeheng; Boonlert Sripairojkul; Prince of Songkla University; Mahidol UniversityObjective: To determine whether patterns of head injury are changing with time. Materials and methods: A total of 3194 and 4217 consecutive trauma patients who attended the emergency room in 1985-86 and 1996 respectively were studied with respect to age, sex, cause of injury, injury severity, pathology, and outcome. Results: The number of patients with head injury in 1996 nearly doubled (1224/4,217:29.03%) when compared to the 1985-86 study (504/3, 194; 15.78%). This was due to an increase in the outpatient subgroup (1009/1224). The admitted patients with head injury showed a pattern of less severe injury. Severe head injury decreased from 12.4 to 7.9%. However, acute subdural haematoma and diffuse brain injury increased from 12.2% and 9% to 32% and 16.8% respectively. The mortality rate of admitted patients increased statistically significantly from 14.4% to 21.8% between the 1985-86 and 1996 studies. Conclusions: This comparative study showed attend toward less severe injury. This may be due to multiple factors. The predominant factor may be the compulsory use of motorcycle helmets. The limitation of this study was that it utilised tertiary hospital based data only. Tertiary hospital receive more and serious head injured patients from surrounding provincial hospitals this may be the major cause of the increased the mortality rate. (C) 2000 Harcourt Publishers Ltd.Publication Metadata only Screening for mutations in the GH-1 gene by dideoxy fingerprinting (ddF)(1999-03-01) Ichiro Miyata; Yoshikatsu Eto; Takashi Kamijo; Masamichi Ogawa; Aree Futrakul; John A. Phillips; Jikei University School of Medicine; Kamiiida Daiichi General Hospital; Nagoya University School of Medicine; Mahidol University; Vanderbilt University School of MedicinePublication Metadata only Treatment of congenital dislocated hip by arthroplasty with femoral shortening(1999-01-01) Keerati Chareancholvanich; Douglas A. Becker; Ramon B. Gustilo; Midwest Orthoped. Res. Foundation; Mahidol UniversityThis was a retrospective study of 15 hips in 11 patients with complete congenital dislocation of the hip treated by total hip arthroplasty and femoral shortening with a subtrochanteric double chevron derotation osteotomy. The mean age at the time of surgery was 51 years (range, 21-74 years), and the mean followup was 5.5 years (range, 2-8.5 years). Functional evaluation using the modified Harris hip rating system showed an excellent result in five hips and a good result in seven hips (80% success rate). The location of the hip center was lowered by a mean of 8.3 cm (range, 5.7-10.4 cm). Leg length discrepancy in seven patients with unilateral involvement was reduced from a mean of 3.9 cm (range, 1.7-8.2 cm) before surgery to a mean of 1.4 cm at the latest followup (range, 0-4 cm). The Trendelenburg sign was assessed in 10 of 15 hips and was corrected from a positive preoperative status to a negative postoperative status in eight of these 10 hips. There were no cases of nonunion, dislocation, nerve palsy, or radiographic loosening. The only complications were a supracondylar fracture below the femoral component in a patient with severe osteoporosis 6 months after surgery and loosening of the cemented titanium metal backed acetabular component in the same patient 1.5 years after surgery. The current series showed that total hip arthroplasty in combination with a subtrochanteric double chevron derotation osteotomy has promising short to midterm results in the treatment of complete congenital dislocation of the hip in adults.Publication Metadata only Lactitol tolerance in healthy Thai adults(1999-10-01) S. Soontornchai; P. Sirichakwal; P. Puwastien; K. Tontisirin; D. Krüger; R. Grossklaus; Sukhothai Thammatirat Open University; Mahidol University; Robert Koch Institut; Fed. Inst. Hlth. Protect. C.The hydrogen breath analysis test was performed in healthy Thai adults to determine lactitol tolerance. The study was conducted in 39 individuals (11 males and 28 females) aged 18-41 years. All volunteers agreed to participate in this study after the risks and benefits had been fully explained. Subjects were requested not to consume milk, milk products, or high-vegetable diets for a day and to fast from 10 p.m. of the day preceding the test day. After consumption of the test diet (12 and 20 g of lactose or lactitol, respectively, in 250 mL water), the subjects recorded the severity of symptoms for 24 hours. Breath samples were collected after fasting and after consumption of the test diet at 30 min intervals over the 7-hour study period. Breath samples were analyzed for hydrogen using gas chromatography. After consumption of 12 g lactose, the prevalence of lactose malabsorbers was established. The increment of a peak breath hydrogen level of ≥ 20 ppm above the baseline level was used as an indicator of lactose malabsorption. The lactose malabsorbers were further classified as lactose tolerants or lactose intolerants according to the gastrointestinal symptoms observed. All 39 healthy Thai adults could be classified into 3 groups as follows: 9 (23%) lactose absorbers (LA), 15 (38.5%) lactose malabsorber/tolerants (LMT), and 15 (38.5%) lactose malabsorber/intolerants (LMI). Using the hydrogen breath test, 67% of the subjects were identified as lactitol intolerants after the consumption of 12 g lactitol. The lactitol intolerants comprised 53.8% of LMI, 34.6% of LMT, and 11.5% of LA. Among all subjects, one third of LA (33%), two thirds of LMT (60%), and 93% of LMI were lactitol intolerant. In addition, gastrointestinal symptoms such as flatulence and abdominal pain were most pronounced in LMI. Diarrhea was also a prominent manifestation after consumption of 12 g lactitol. Therefore, it was finally decided that 20 g lactose or lactitol were not given to LMI because of the risk of gastrointestinal symptoms. After high doses (20 g) of lactose and lactitol consumption, most LMT developed more symptoms than did LA and the main symptom was diarrhea. Consumption of 20 g lactose resulted in fewer symptoms than 20 g lactitol in both LA and LMT. On the basis of the hydrogen breath test, most LA tolerated 12 g lactitol without gastrointestinal symptoms except some flatulence whereas most LMT and LMI did not. Twenty g lactitol was not tolerated by both LA and LMT because there was diarrhea among the subjects, especially in LMT. Although the hydrogen breath analysis test is the best method for identification of lactose malabsorption, it is not the best method to identify lactitol intolerance. A hydrogen concentration of 15 ppm above the baseline level was found to be the best cut-off point to indicate lactitol intolerance although sensitivity was 85% and specificity only 38% in this study. It was further concluded that there is a greater susceptibility to lactitol in human lactose malabsorbers than in lactose absorbers. Our findings might be relevant for the limited use of lactitol in Thailand.Publication Metadata only A solitary-wave solution to a perturbed KdV equation(2000-01-01) M. A. Allen; G. Rowlands; Mahidol University; The University of WarwickWe derive the approximate form and speed of a solitary-wave solution to a perturbed KdV equation. Using a conventional perturbation expansion, one can derive a first-order correction to the solitary-wave speed, but at the next order, algebraically secular terms appear, which produce divergences that render the solution unphysical. These terms must be treated by a regrouping procedure developed by us previously. In this way, higher-order corrections to the speed are obtained, along with a form of solution that is bounded in space. For this particular perturbed KdV equation, it is found that there is only one possible solitary wave that has a form similar to the unperturbed soliton solution.Publication Metadata only Percutaneous transluminal coronary angioplasty in the young patients - Siriraj Hospital's experience(2000-11-01) Lily Singhaviranon; Nithi Mahanonda; Chunhakasem Chotinaiwattarakul; Anna Chirapastan; Burin Kwo-Sa-Ard; Prajak Tanapibunpon; Amonwan Kanabencha; Tavorn Jaidee; Supachai Chaithiraphan; Mahidol UniversityThe aim of this study was to follow-up immediate and long term results of patients aged less than 40 years with CAD treated by PTCA. Primary end points were to record major coronary events, incidence and timing of restenosis and requirement of repeated revascularization after initial PTCA. Data was collected retrospectively from records of patients aged less than 40 years who underwent PTCA from Jan 1996 to June 1998 in Her Majesty Cardiac Center, Siriraj Hospital. Patients were followed up and data was collected regarding recurrent angina, major coronary events and results of repeated coronary angiography and revascularization if available. Out of 830 procedures performed for 325 patients, 30 patients (9%) were less than 40 years of age and comprised of 26males (87%) and 4 females (13%). Eighteen patients (60%) had more than one risk factor. The most important risk factor was smoking (60%) followed by dyslipidaemia (47%) and family history of coronary artery disease (20%). DM was strikingly uncommon. 14 patients had single vessel disease and 16 patients had multiple vessel disease. Initial stenosis was 87.5 ± 9.8 and residual stenosis was 17.8 ± 10.8. PTCA failed for 5 lesions, overall success rate was 89 per cent. Stent was used for 12 lesions in 10 patients. There was no major complication during the procedure. Minor complications included non occlusive dissection in four cases and groin haematoma in three cases. The follow up ranged from 7-36 months with the median of 23 months. During follow up, there was no major cardiac event such as death, acute MI, congestive heart failure or cerebero-vascular accident. Eleven patients (37%) had sustained improvement without recurrent angina. Recurrent angina occurred in 19 patients (63%) after initial PTCA and second/third recurrent angina occurred in 5 patients. On repeated coronary angiography angiographic restenosis was seen in 10 patients (33%) after initial PTCA. Overall repeated revascularization was done twenty times for sixteen patients which included 4 CABGs and 16 PTCA. Twenty one patients (70%) showed sustained improvement after repeated PTCA and medications. Follow up results of PTCA in young patients showed sustained improvement but achieved at high rate of repeated revascularization.Publication Metadata only The use of allozymes and shell morphology to distinguish among sympatric species of the rock oyster Saccostrea in Thailand(2000-07-05) A. J. Day; A. J.S. Hawkins; P. Visootiviseth; Plymouth Marine Laboratory; Mahidol UniversityThree hundred and fifty-five Saccostrea oysters from 12 sites throughout Thailand were scored for allozyme variation at eight enzyme loci (Aat-1, Ap, Est-2, Lap, Mdh-1, Mpi, Pgi and Pgm). Allelic variation within Lap, Pgi, Pgm and Mpi loci was concordant. Principle component analysis (PCA) of these four loci identified two principal components (PC1 and PC2) that resolved individuals into three discrete clusters corresponding to different species. Oysters were assigned to different species by diagnostic alleles at Lap, Mpi and Pgi loci, and correct identification confirmed by a comparison of observed genotype frequencies in putative single-species samples with those expected under Hardy-Weinberg equilibrium. We identified one of these species as Saccostrea commercialis, based on identical mobility's at all eight loci to a reference sample of that species from Australia. The other two species we identified as S. cucullata and S. manilai by comparison of relative allozyme mobility's and shell morphology traits with data published for these species. S. commercialis and S. manilai were found in sympatry in coastal and estuarine sites throughout the Gulf of Thailand. S. cucullata was restricted to offshore islets. Ten measurements were made on the shells of a subset of oysters from seven sites. Observations were also made of adductor scar colour and chomata spacing. Principal component analysis of shell morphometrics of ninety oysters identified by allozymes revealed three principal components that varied between species. These reflected variation in overall size, degree of 'cupping' of left valve, and relative size of the umbo cavity. The most useful character for species identification was the size of the umbo cavity, which was large in S. cucullata and S. commercialis, but almost non-existent in S. manilai. Mean umbo depths were 1.49 cm for S. cucullata, 0.7 cm for S. commercialis and 0.42 cm for S. manilai. Colour of the adductor scar was also of taxonomic value, with 75% of S. cucullata having black scars, while scars were white or brown in the other two species. (C) 2000 Elsevier Science B.V.Publication Metadata only Mefloquine concentration profiles during prophylactic dose regimens(2000-05-19) Herwig Kollaritsch; Juntra Karbwang; Gerhard Wiedermann; Andrea Mikolasek; Kesara Na-Bangchang; Walter H. Wernsdorfer; Mahidol University; Universitat WienA pharmacokinetic study with (malaria) prophylactic doses of mefloquine hydrochloride was conducted in 12 healthy adult subjects (Caucasians), 6 females and 6 males, mean age 29.2 ± 6.4 years, mean weight 70.6 ± 13.4 kg. Doses of 250 mg mefloquine were administered on days 0, 1, 7, 14, 21 and 28. Six subjects received a further 5 weekly doses of 250 mg mefloquine, the others 5 further weekly doses of 125 mg. After the third dose the protective threshold mefloquine concentration in blood plasma was achieved in all subjects. In female subjects, mean C(min ss), C(max) ss and AUC(d 0-35) were significantly higher than in males. After the fifth dose, mean Cmax in females reached 1692 ng/ml (4.48 μmol/l), equivalent to a high therapeutic concentration. This is apparently due to a generally lower body weight and a narrower volume of distribution in women. Adverse reactions were significantly more frequent in women than in men. Headache, anorexia, insomnia and vertigo were the most common side effects. The lesser tolerability of mefloquine in females may be due to the higher drug concentrations in this group. This may indicate the need for appropriate adjustment of the prophylactic dose regimen of mefloquine in females.Publication Metadata only Transarterial embolization of vein of galen aneurysmal malformations: 3 cases(2000-01-01) P. Jiarakongmun; S. Pongpech; S. Siriwimolmas; P. Lasjuanias; Mahidol UniversityPublication Metadata only Mechanical carrier of bacterial enteric pathogens by Chrysomya megacephala (diptera: calliphoridae) in Chiang Mai, Thailand(2000-12-01) Kabkaew Sukontason; Manasanant Bunchoo; Banyong Khantawa; Somsak Piangjai; Kom Sukontason; Rungkarn Methanitikorn; Yupha Rongsriyam; Chiang Mai University; Mahidol UniversityChrysomya megacephala was studied regarding its mechanically bacterial carrier in urban areas of Chiang Mai, northern Thailand. Fifty-six adult flies were randomly collected using sweep insect net during April-May. 1999 from 3 fresh food markets and examined for bacteriological isolation. Among them, 49 flics (87.5%) were bacterial carriers. The total 22 bacterial species and 8 groups were isolated. Three species previously reported as the bacterial enteric pathogens causing diarrheal disease were isolated from 5 flies, ie Aeromonas hydrophila, Edwardsiella tarda and Vibrio cholerae non-01, with their prevalence rates in flies being 3.57%. 1.79% and 3.57%, respectively. Five possible bacteria enteric pathogens, ie Aeromonas sobria, Citrobacter freundii, Escherichia coli, Providencia alcalifaciens and Pseudomonas aeruginosa, were isolated from 21 flies with the prevalence rates in flies being 5.34%, 3.57%, 26.79%, 7.14% and 1.79%, respectively. The bacterial load isolated from all 3 pathogenic species was entirely found more than 103colony per fly, indicating the high chance for disease transmission via this fly species. C. megacephala may play the possible and/or important role of bacterial enteric pathogens transmission, thereby promoting the public health personnel for sanitation improvement in fresh food markets and fly control management in these particular areas.Publication Metadata only Inducible nitric oxide synthase expression is increased in the brain in fatal cerebral malaria(2000-09-26) Y. Maneerat; P. Viriyavejakul; B. Punpoowong; M. Jones; P. Wilairatana; E. Pongponratn; G. D.H. Turner; R. Udomsangpetch; Mahidol University; University of Oxford; John Radcliffe HospitalAims: Nitric oxide (NO) has been hypothesized to play a major role in the pathogenesis of cerebral malaria caused by P. falciparum infection. NO may act as a local neuroactive mediator contributing to the coma of cerebral malaria (CM). We hypothesized that increased expression of inducible nitric oxide synthase (iNOS) may cause increased release of NO, and examined the expression and distribution of iNOS in the brain during CM. Material and results: Brain tissues from fatal cases of cerebral malaria in Thai adults were examined using immunohistochemical staining to detect iNOS. The distribution and strength of staining was compared between 14 patients with CM, three of whom were recovering from coma, and controls, iNOS expression was found in endothelial cells, neurones, astrocytes and microglial cells in CM cases. There was also strong staining in macrophages surrounding ring haemorrhages, iNOS staining was decreased in recovering malaria cases compared to acute CM, and was low in controls. Quantification showed a significant association between the intensity and number of iNOS positive vessels with the severity of malaria related histopathological changes, although the total number of cells staining was not increased compared to recovering CM cases. Conclusions: This study indicates that an acute induction of iNOS expression occurs in the brain during CM. This occurs in a number of different cells types, and is increased in the acute phase of CM compared to cases recovering from coma. As NO may activate a number of secondary neuropathological mechanisms in the brain, including modulators of synaptic function, induction of iNOS expression in cerebral malaria may contribute to coma, seizures and death.Publication Metadata only Differential effects of ovariectomy on calcium activation of cardiac and soleus myofilaments(1999-08-01) Jonggonnee Wattanapermpool; Peter J. Reiser; Mahidol University; Ohio State UniversityThe hypothesis that ovarian sex hormone deficiency affects cardiac myofilament activation was tested. Chemically skinned ventricular trabeculae and single soleus muscle fibers were prepared from 10- and 14-wk ovariectomized and control rats. Tension-pCa (-log [Ca2+]) relations of left ventricular trabeculae and soleus fibers were compared to test whether thin filament proteins are potential sites of modulated activation. Trabeculae from ovariectomized rats exhibited a significant increase in Ca2+ sensitivity with no change in maximal tension-generating ability. In contrast, soleus fibers demonstrated no shift in Ca2+ sensitivity but generated significantly less maximal tension. No changes in thin filament protein isoform expression or loss of thin filament proteins were apparent in the trabeculae or soleus fibers from ovariectomized rats. Although not directly tested, our results are consistent with a possible modulation of regulatory proteins (e.g., cardiac troponin I) to account for the observed change in myofilament responsiveness of hearts from ovariectomized rats. Other possible mechanisms for the altered myocardial Ca2+ sensitivity after ovariectomy are discussed.