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Showing papers by "Mahidol University published in 1999"


Journal ArticleDOI
TL;DR: A short course of twice-daily oral zidovudine was safe and well tolerated and, in the absence of breastfeeding, can lessen the risk for mother-to-child HIV-1 transmission by half.

804 citations


Journal ArticleDOI
TL;DR: Strain differentiation by IS6110 RFLP or mixed-linker PCR are the methods of choice for epidemiological investigations, indicating a clonal population structure of M. tuberculosis strains.
Abstract: In this study, the currently known typing methods for Mycobacterium tuberculosis isolates were evaluated with regard to reproducibility, discrimination, and specificity Therefore, 90 M tuberculosis complex strains, originating from 38 countries, were tested in five restriction fragment length polymorphism (RFLP) typing methods and in seven PCR-based assays In all methods, one or more repetitive DNA elements were targeted The strain typing and the DNA fingerprint analysis were performed in the laboratory most experienced in the respective method To examine intralaboratory reproducibility, blinded duplicate samples were included The specificities of the various methods were tested by inclusion of 10 non-M tuberculosis complex strains All five RFLP typing methods were highly reproducible The reliability of the PCR-based methods was highest for the mixed-linker PCR, followed by variable numbers of tandem repeat (VNTR) typing and spoligotyping In contrast, the double repetitive element PCR (DRE-PCR), IS6110 inverse PCR, IS6110 ampliprinting, and arbitrarily primed PCR (APPCR) typing were found to be poorly reproducible The 90 strains were best discriminated by IS6110 RFLP typing, yielding 84 different banding patterns, followed by mixed-linker PCR (81 patterns), APPCR (71 patterns), RFLP using the polymorphic GC-rich sequence as a probe (70 patterns), DRE-PCR (63 patterns), spoligotyping (61 patterns), and VNTR typing (56 patterns) We conclude that for epidemiological investigations, strain differentiation by IS6110 RFLP or mixed-linker PCR are the methods of choice A strong association was found between the results of different genetic markers, indicating a clonal population structure of M tuberculosis strains Several separate genotype families within the M tuberculosis complex could be recognized on the basis of the genetic markers used

616 citations



Journal ArticleDOI
TL;DR: There are good arguments for no longer using antimalarial drugs alone in treatment, and instead always using a combination with artemisinin or one of its derivatives.
Abstract: Antimarial drug resistance develops when spontaneously occurring parasite mutants with reduced susceptibility are selected, and are then transmitted. Drugs for which a single point mutation confers a marked reduction in susceptibility are particularly vulnerable. Low clearance and a shallow concentration-effect relationship increase the chance of selection. Use of combinations of antimalarials that 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 per parasite mutation rates for the individual drugs, multiplied by the number of parasites in an infection that are exposed to the drugs. Artemisinin derivatives are particularly effective combination partners because (i) they are very active antimalarials, producing up to 10,000-fold reductions in parasite biomass per asexual cycle; (ii) they reduce malaria transmissibility; and (iii) no resistance to these drugs has been reported yet. There are good arguments for no longer using antimalarial drugs alone in treatment, and instead always using a combination with artemisinin or one of its derivatives.

497 citations


Journal ArticleDOI
TL;DR: Antimalarial treatment arrests development at the trophozoite stages which remain sequestered in the brain, indicating that the adhesion characteristics of cerebrovascular endothelium change asynchronously during malaria and also that significant recirculation of parasitized erythrocytes following sequestration is unlikely.
Abstract: Microvascular sequestration was assessed in the brains of 50 Thai and Vietnamese patients who died from severe malaria (Plasmodium falciparum, 49; P. vivax, 1). Malaria parasites were sequestered in 46 cases; in 3 intravascular malaria pigment but no parasites were evident; and in the P. vivax case there was no sequestration. Cerebrovascular endothelial expression of the putative cytoadherence receptors ICAM-1, VCAM-1, E-selectin, and chondroitin sulfate and also HLA class II was increased. The median (range) ratio of cerebral to peripheral blood parasitemia was 40 (1.8 to 1500). Within the same brain different vessels had discrete but different populations of parasites, indicating that the adhesion characteristics of cerebrovascular endothelium change asynchronously during malaria and also that significant recirculation of parasitized erythrocytes following sequestration is unlikely. The median (range) ratio of schizonts to trophozoites (0.15:1; 0.0 to 11.7) was significantly lower than predicted from the parasite life cycle (P < 0.001). Antimalarial treatment arrests development at the trophozoite stages which remain sequestered in the brain. There were significantly more ring form parasites (age < 26 hours) in the cerebral microvasculature (median range: 19%; 0-90%) than expected from free mixing of these cells in the systemic circulation (median range ring parasitemia: 1.8%; 0-36.2%). All developmental stages of P. falciparum are sequestered in the brain in severe malaria.

379 citations


Journal ArticleDOI
TL;DR: P. vivax malaria during pregnancy is associated with maternal anaemia and low birthweight, and antimalarial prophylaxis against P.vivax in pregnancy may be justified.

360 citations


Journal ArticleDOI
TL;DR: Characterisation of these pharmacokinetic-pharmacodynamic relationships provided the basis for dosage optimisation, an approach that could be applied to other antimalarial drugs.
Abstract: The combination of artemether and lumefantrine (benflumetol) is a new and very well tolerated oral antimalarial drug effective even against multidrug-resistant falciparum malaria. The artemether component is absorbed rapidly and biotransformed to dihydroartemisinin, and both are eliminated with terminal half-lives of around 1 hour. These are very active antimalarials which give a rapid reduction in parasite biomass and consequent rapid resolution of symptoms. The lumefantrine component is absorbed variably in malaria, and is eliminated more slowly (half-life of 3 to 6 days). Absorption is very dependent on coadministration with fat, and so improves markedly with recovery from malaria. Thus artemether clears most of the infection, and the lumefantrine concentrations that remain at the end of the 3- to 5-day treatment course are responsible for eliminating the residual 100 to 10 000 parasites. The area under the curve of plasma lumefantrine concentrations versus time, or its correlate the plasma concentration on day 7, has proved an important determinant of therapeutic response. Characterisation of these pharmacokinetic-pharmacodynamic relationships provided the basis for dosage optimisation, an approach that could be applied to other antimalarial drugs.

310 citations


Journal ArticleDOI
TL;DR: The relationship between pfmdr1 and resistance to structurally distinct antimalarial agents confirms the presence of a true multidrug-resistant phenotype.
Abstract: On the western border of Thailand, Plasmodium falciparum has become resistant to almost all antimalarial agents. The molecular basis of resistance in these parasite populations has not been well characterized. This study assessed genetic polymorphisms in the pfmdr1 gene in 54 parasites collected from the western border of Thailand to determine the relationship of pfmdr1 copy number and codon mutations with parasite sensitivities to mefloquine, chloroquine, halofantrine, quinine, and artesunate assessed in vitro. A point mutation at codon 86 (resulting in a change of Asn to Tyr) was associated with a significantly lower 50% inhibitory concentration (IC(50)) of mefloquine (median, 9 ng/ml versus 52.4 ng/ml; P = 0.003). Overall 35% of the isolates (19 of 54) had an increase in pfmdr1 copy number, and all 19 carried the wild-type allele at codon 86. Increased pfmdr1 copy number was associated with higher IC(50)s of mefloquine (P = 0.04) and artesunate (P = 0.005), independent of polymorphism at codon 86. The relationship between pfmdr1 and resistance to structurally distinct antimalarial agents confirms the presence of a true multidrug-resistant phenotype.

284 citations


Journal ArticleDOI
TL;DR: The anticough activity of Psidium guajava Linn.

263 citations


Journal Article
TL;DR: 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.
Abstract: Resistance 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.

258 citations


Journal ArticleDOI
TL;DR: All US isolates could be differentiated by a unique, strain‐specific PCR fingerprint or RAPD pattern in contrast to most of the non‐US isolates, which showed a substantially higher degree of genetic homogeneity, with some clonality, in different parts of the world.
Abstract: A total of 356 clinical isolates of the encapsulated basidiomycetous fungus Cryptococcus neoformans var. neoformans, obtained from Australia, Argentina, Brazil, India, Italy, New Zealand, Papua New Guinea, South Africa, Thailand and the USA, were analyzed to lay the basis for a comprehensive evaluation of the global genetic structure of C. neoformans. Two polymerase chain reaction (PCR)-based typing techniques were standardized: PCR fingerprinting using a single primer specific to minisatellite or microsatellite DNA, and randomly amplified polymorphic DNA (RAPD) analysis using two combinations of three 20- to 22-mer random primers. Previous studies showed that the resultant profiles are reproducible and stable over time. Identical results were obtained in two different laboratories and by different scientists in the same laboratory. Both typing techniques separated the isolates into four major groups (VNI and VNII, serotype A; VNIII, serotype A/D; and VNIV, serotype D). The majority (78%) of isolates belonged to VNI, compared with 18% VNII, 1% VNIII and 3% VNIV. All US isolates could be differentiated by a unique, strain-specific PCR fingerprint or RAPD pattern in contrast to most of the non-US isolates, which showed a substantially higher degree of genetic homogeneity, with some clonality, in different parts of the world. Isolates obtained from the same patient at different times and from different body sites, had identical banding patterns. Both typing techniques should provide powerful tools for epidemiological studies of medically important fungi.

Journal ArticleDOI
TL;DR: Data is analyzed from a 75-g oral glucose tolerance test performed on 1051 high-risk subjects without medical history of diabetes at Diabetes Screening Clinic, Ramathibodi Hospital, Thailand to compare 1997 ADA diagnostic criteria for diabetes mellitus and other categories of glucose intolerance/1998 WHO Consultation criteria versus 1985 WHO criteria.

Journal ArticleDOI
TL;DR: There appear to be no significant differences in the incidence and extent of root resorption and ankylosis in dogs implanted with recombinant human bone morphogenetic protein-2, though there may be a positive correlation with rhBMP-2 concentration.
Abstract: The objective of this study was to evaluate the effect of recombinant human bone morphogenetic protein-2 (rhBMP-2) concentration on regeneration of alveolar bone and cementum, and on associated root resorption and ankylosis. Contralateral, critical size, supra-alveolar, periodontal defects were surgically produced and immediately implanted with rhBMP-2 in an absorbable collagen sponge (ACS) carrier in 8, young adult, male, beagle dogs. 6 animals received rhBMP-2/ACS (rhBMP-2 at 0.05, 0.10, or 0.20 mg/mL; total construct volume/defect approximately 4.0 mL) in contralateral defects following an incomplete block design. 2 animals received rhBMP-2/ACS (rhBMP-2 at 0 and 0.10 mg/mL) in contralateral defects (controls). The animals were euthanised at 8 weeks post-surgery and block sections of the defects were collected for histologic and histometric analysis. Supra-alveolar periodontal defects receiving rhBMP-2 at 0.05, 0.10, or 0.20 mg/ml exhibited extensive alveolar regeneration comprising 86%, 96%, and 88% of the defect height, respectively. Cementum regeneration encompassed 8%, 6%, and 8% of the defect height, respectively. Root resorption was observed for all rhBMP-2 concentrations. Ankylosis was observed in almost all teeth receiving rhBMP-2. Control defects without rhBMP-2 exhibited limited, if any, evidence of alveolar bone and cementum regeneration, root resorption, or ankylosis. Within the selected rhBMP-2 concentration and observation interval, there appear to be no meaningful differences in regeneration of alveolar bone and cementum. There also appear to be no significant differences in the incidence and extent of root resorption and ankylosis, though there may be a positive correlation with rhBMP-2 concentration.

Journal ArticleDOI
TL;DR: Treatment with atovaquone and proguanil hydrochloride was significantly more effective than mefloquine (Thailand), amodiaquine (Gabon), chloroquine(Peru and the Philippines) or chloroquines plus pyrimethamine/sulfadoxine (Philippines), in clinical trials where the comparator drug was highly effective.
Abstract: The continuing spread of drug-resistant malaria emphasizes the need for new antimalarial drugs. Atovaquone is a broad-spectrum antiprotozoal drug with a novel mechanism of action, via inhibition of parasite mitochondrial electron transport, and a favorable safety profile. Early studies with atovaquone alone for treatment of malaria demonstrated good initial control of parasitemia but an unacceptable rate of recrudescent parasitemia. Parasites isolated during recrudescence after treatment with atovaquone alone were resistant to atovaquone in vitro. The combination of atovaquone and proguanil is synergistic in vitro, and clinical studies demonstrated enhanced efficacy of the combination compared to either drug alone for treatment of malaria. Malarone, a fixed-dose combination of 250 mg of atovaquone and 100 mg of proguanil hydrochloride, is available in many countries for treatment of acute, uncomplicated malaria caused by Plasmodium falciparum. At the recommended dose (in adults, four tablets once a day for three days), the overall cure rate was > 98% in more than 500 patients with falciparum malaria. In four randomized, controlled clinical trials, treatment with atovaquone and proguanil hydrochloride was significantly more effective than mefloquine (Thailand), amodiaquine (Gabon), chloroquine (Peru and the Philippines) or chloroquine plus pyrimethamine/sulfadoxine (Philippines). In clinical trials where the comparator drug was highly effective, treatment with atovaquone and proguanil hydrochloride was equally effective. Parasites isolated during recrudescence after treatment with the combination of atovaquone and proguanil were not resistant to atovaquone in vitro. The most commonly reported adverse events in clinical trials (abdominal pain, anorexia, nausea, vomiting, diarrhea and coughing) occurred with similar frequency in patients treated with a comparator drug. Malarone is a safe and effective new agent for treatment of malaria.

Journal ArticleDOI
TL;DR: Imipenem is a safe and effective treatment for acute severe melioidosis and may be considered an alternative to ceftazidime and the main outcome measures were death or treatment failure.
Abstract: An open, prospective, randomized, comparative treatment trial was conducted to compare the therapeutic efficacy of high-dose intravenous imipenem and ceftazidime for acute severe melioidosis. Adult Thai patients with suspected acute, severe melioidosis were randomized to receive either imipenem, at a dosage of 50 mg/(kg.d), or ceftazidime, at a dosage of 120 mg/(kg.d), for a minimum of 10 days. The main outcome measures were death or treatment failure. Of the 296 patients enrolled, 214 had culture-confirmed melioidosis, and 132 (61.7%) of them had positive blood cultures. Mortality among patients with melioidosis was 36.9% overall. There were no differences in survival overall (P = .96) or after 48 hours (P = .3). Treatment failure after 48 hours was more common among patients treated with ceftazidime (P = .011). Both treatments were well tolerated. Imipenem is a safe and effective treatment for acute severe melioidosis and may be considered an alternative to ceftazidime.

Journal ArticleDOI
TL;DR: Nasopharyngeal and oral carcinoma patients from Malaysia, Hong Kong and Sri Lanka who have very high EBV titres show that there is little, if any, cross-reactivity between antibodies to these two gamma viruses, suggesting that human herpes virus-8 (HHV-8) may be either a recently introduced virus or one that has extremely low infectivity.
Abstract: Seroprevalence of HHV-8 has been studied in Malaysia, India, Sri Lanka, Thailand, Trinidad, Jamaica and the USA, in both healthy individuals and those infected with HIV. Seroprevalence was found to be low in these countries in both the healthy and the HIV-infected populations. This correlates with the fact that hardly any AIDS-related Kaposi's sarcoma has been reported in these countries. In contrast, the African countries of Ghana, Uganda and Zambia showed high seroprevalences in both healthy and HIV-infected populations. This suggests that human herpes virus-8 (HHV-8) may be either a recently introduced virus or one that has extremely low infectivity. Nasopharyngeal and oral carcinoma patients from Malaysia, Hong Kong and Sri Lanka who have very high EBV titres show that only 3/82 (3.7%) have antibody to HHV-8, demonstrating that there is little, if any, cross-reactivity between antibodies to these two gamma viruses.

Journal ArticleDOI
TL;DR: Phaco-GSL and PCIOL implantation is effective in reducing PAS and IOP and improving visual acuity in eyes with persistent chronic ACG when performed within 6 months after treatment for acute ACG.

Journal ArticleDOI
TL;DR: Fish, in general, contained NPN at the level of less than 15% of total nitrogen, except 22% in raw, salted and sun-dried snake skin gourami, which equals 22% of Thai Recommended Daily Intake (Thai RDI).

Journal ArticleDOI
TL;DR: Primers can be combined in a single PCR reaction providing a rapid, sensitive and straightforward method of species identification, and only small quantities of DNA are required, leaving most of the mosquito to be used for other analyses.
Abstract: The Anopheles dirus complex of mosquitoes contains some of the most important vectors of malaria in Southeast Asia. To distinguish five species of the complex that occur in Thailand, a method using the polymerase chain reaction (PCR) was developed. The method utilizes allele-specific amplification to detect fixed differences between the species in the DNA sequence of the ribosomal DNA internal transcribed spacer 2. Primers were designed to amplify fragments of diagnostic length from the DNA of the different species. The method was tested on 179 mosquitoes of the An. dirus complex from many parts of Thailand and shown to be effective. Every specimen was unambiguously identified as species A, B, C, D or F (i.e. An. dirus s.s. species B, C, D or An. nemophilous, respectively) by the PCR method, with confirmation of 58/61 identifications from polytene chromosome characteristics. For the other three specimens (3/44 from Kanchanaburi 5 locality), there was disagreement between the PCR and chromosomal methods of species identification (probably due to errors in the chromosomal identifications). Primers can be combined in a single PCR reaction providing a rapid, sensitive and straightforward method of species identification. Only small quantities of DNA are required, leaving most of the mosquito to be used for other analyses.

Journal ArticleDOI
TL;DR: Parasite genotyping by the polymerase chain reaction was used to distinguish recrudescent from newly acquired Plasmodium falciparum infections in a Karen population resident on the northwestern border of Thailand where malaria transmission is low.
Abstract: Parasite genotyping by the polymerase chain reaction was used to distinguish recrudescent from newly acquired Plasmodium falciparum infections in a Karen population resident on the northwestern border of Thailand where malaria transmission is low (one infection/person/year). Plasmodium falciparum infections were genotyped for allelic variation in three polymorphic antigen loci, merozoite surface proteins-1 and -2 (MSP-1 and -2) and glutamaterich protein (GLURP), before and after antimalarial drug treatment. Population genotype frequencies were measured to provide the baseline information to calculate the probability of a new infection with a different or the same genotype to the initial pretreatment isolate. Overall, 38% of the infections detected following treatment had an identical genotype before and up to 121 days after treatment. These post-treatment genotypes were considered recrudescent because of the low (< 5%) probability of repeated occurrence by chance in the same patient. This approach allows studies of antimalarial drug treatment to be conducted in areas of low transmission since recrudescences can be distinguished confidently from newly acquired infections.

Journal ArticleDOI
TL;DR: Data suggest that during gram-negative sepsis, IFN-gamma production is controlled at least in part by endogenous IL-18, IL-12, and IL-15.
Abstract: Interferon (IFN)-gamma plays an important role in the pathogenesis of sepsis. Production of IFN-gamma is stimulated by synergistic effects of interleukin (IL)-18, IL-12, and IL-15. To investigate the regulation of IFN-gamma production during severe gram-negative infection, the plasma concentrations of IFN-gamma, IL-18, IL-12, and IL-15 were measured in 83 patients with suspected melioidosis. The diagnosis was confirmed in 62 patients, 31 of whom had blood cultures positive for Burkholderia pseudomallei, of whom 12 died. Compared with healthy controls, patients had elevated levels of IFN-gamma, IL-18, IL-12p40, and IL-15 on admission, with significantly higher levels in blood culture-positive patients, and these levels remained elevated during the 72-h study period. In whole blood stimulated with heat-killed B. pseudomallei, anti-IL-12 had a stronger inhibitory effect than anti-IL-18 and anti-IL-15 on IFN-gamma production. This effect of anti-IL-12 was further enhanced by anti-IL-18. These data suggest that during gram-negative sepsis, IFN-gamma production is controlled at least in part by endogenous IL-18, IL-12, and IL-15.

Journal ArticleDOI
TL;DR: A lower antib bacterial activity was detected in samples treated with LPS after clotting (HLF), than in those treated before clotting, suggesting that LPS was involved in mechanisms for both clotting and for antibacterial activity.

Journal ArticleDOI
TL;DR: A new fluorescence in situ hybridization (FISH) method using peptide nucleic acid (PNA) probes for differentiation between species of the Mycobacterium tuberculosis complex (MTC) and nontuberculous mycobacteria (NTM) in acid-fast bacillus-positive (AFB+) cultures is described.
Abstract: TB PNA FISH is a new fluorescence in situ hybridization (FISH) method using peptide nucleic acid (PNA) probes for differentiation between species of the Mycobacterium tuberculosis complex (MTC) and nontuberculous mycobacteria (NTM) in acid-fast bacillus-positive (AFB+) cultures is described. The test is based on fluorescein-labelled PNA probes that target the rRNA of MTC or NTM species applied to smears of AFB+ cultures for microscopic examination. Parallel testing with the two probes serves as an internal control for each sample such that a valid test result is based on one positive and one negative reaction. TB PNA FISH was evaluated with 30 AFB+ cultures from Denmark and 42 AFB+ cultures from Thailand. The MTC-specific PNA probe showed diagnostic sensitivities of 84 and 97%, respectively, and a diagnostic specificity of 100% in both studies, whereas the NTM-specific PNA probe showed diagnostic sensitivities of 91 and 64%, respectively, and a diagnostic specificity of 100% in both studies. The low sensitivity of the NTM-specific PNA probe in the Thai study was due to a relatively high prevalence of Mycobacterium fortuitum, which is not identified by the probe. In total, 63 (87%) of the cultures were correctly identified as MTC (n = 46) or NTM (n = 17), whereas the remaining 9 were negative with both probes and thus the results were inconclusive. None of the samples were incorrectly identified as MTC or NTM; thus, the predictive value of a valid test result obtained with TB PNA FISH was 100%.

Journal ArticleDOI
TL;DR: Spinal accessory nerve transfer should be used when motor function of the elbow flexors is the major concern and intercostal nerve transfer is performed in patients who need both motor and sensory reconstruction and in those who have chronic pain syndrome after brachial plexus injury.
Abstract: This study was performed to compare the clinical outcome of 2 types of commonly used nerve transfers, the spinal accessory nerve transfer and the intercostal nerve transfer. This study was a prospective randomized parallel trial involving 205 patients presenting between 1989 and 1994. All patients were males ranging in age from 16 to 43 years. All patients underwent surgery within 6 months of injury. Spinal accessory nerve transfer was performed in 130 patients; better results were obtained in terms of less operative time, fewer blood transfusions, fewer immediate complications, and better motor function (very good and good power in 83% of patients). Intercostal nerve transfer was performed in 75 patients; better results were observed in terms of earlier electromyographic evidence of motor reinnervation, improvement in protective sensation, and reduction of pain. However, very good and good motor recovery was observed in only 64% of patients. There was no significant difference with regard to tidal volume, vital capacity, and the FEV1 to FEV ratio before and after surgery in either group. Smoking adversely affected the rate of recovery. Spinal accessory nerve transfer should be used when motor function of the elbow flexors is the major concern. Intercostal nerve transfer should be performed in patients who need both motor and sensory reconstruction and in those who have chronic pain syndrome after brachial plexus injury.

Journal ArticleDOI
TL;DR: There is an imperative need for cheap, well-tolerated drugs that can be used in short courses, and for strategies to delay the onset of drug resistance.
Abstract: Malaria still kills some 0.5-2.5 million people per year in the tropics. Resistance to the cheap, most commonly used antimalarials continues to spread alarmingly and could outpace drug development. The artemisinin derivatives have had an important clinical impact both on the treatment of resistant falciparum malaria and on the incidence of disease in low-transmission areas. A few promising new antimalarials are being tested clinically but there is an imperative need for cheap, well-tolerated drugs that can be used in short courses, and for strategies to delay the onset of drug resistance. Bed nets have been shown to reduce the incidence of severe malaria in many areas but an effective vaccine is urgently needed.

Journal ArticleDOI
TL;DR: Interventions are proposed which address disclosure issues, feelings of shame and coping strategies as well as financial assistance for single mothers which require few resources such as group counselling or support merit special consideration.

Journal ArticleDOI
TL;DR: A small pilot study is performed to assess the knowledge, attitude, and practice of epilepsy in the schoolteachers in Thailand whose major impact on the children is manifested by attitudes and learning.
Abstract: Summary: Purpose: Epilepsy is one of the most common neurologic disorders of childhood. However, in Thailand, as well as in most of other developing countries, little attention has been paid to improve the public knowledge regarding epilepsy. Currently public attitude toward epilepsy is rather negative, full of prejudices and bias. Children with epilepsy in Thailand still find themselves confronted with social barriers that prevent them from academic achievements, in addition to the limitation that the disease itself has already placed on them. To delineate the magnitude and scope of this problem, we performed a small pilot study to assess the knowledge, attitude, and practice of epilepsy in the schoolteachers in Thailand whose major impact on the children is manifested by attitudes and learning. Methods: The study was conducted by sending simple self-administered questionnaires to 360 schools all over Thailand. The questionnaires contained 14 questions relating to epilepsy awareness, attitudes, and first-aid management of seizures. Results: We found that 38% of respondents had not heard of or read about epilepsy, and 46.6% believed that epilepsy is a chronic incurable disease. Fifteen percent of the respondents preferred to place all children with epilepsy in a special classroom. Furthermore, half of the respondents who had experience with first-aid management of seizures used improper and potentially harmful measures. Conclusions: Besides the proper management of epilepsy, a general public education campaign for epilepsy and the need to address and correct the existing biases are necessary to improve the quality of life of children with epilepsy in Thailand.

Journal ArticleDOI
TL;DR: At the 3 year follow-up, most patients had encouraging recovery of sensory function in the hand but motor function of the forearm and hand muscles was rather poor and acceptable motor function was found in only 50 to 60% of the patients who were younger than 18 years.
Abstract: This prospective study was carried out to assess motor and sensory recovery after contralateral C7 root to median nerve neurotization in brachial plexus injuries with total root avulsions. The survey was carried out from 1993 to 1995 and the patients were followed up for at least 3 years. There were 96 male patients with ages ranging from 13 to 48 years. All had a unilateral brachial plexus injury with avulsion of all roots. This was confirmed by clinical assessment and exploration. The anterior part of the contralateral C7 root was used for neurotization via a reversed pedicular ulnar nerve graft and the proximal end of the graft was connected to the median nerve. Furthermore, phrenic nerve to suprascapular nerve and spinal accessory nerve (via a sural nerve graft) to musculocutaneous nerve neurotizations were also carried out to obtain shoulder abduction and elbow flexion. At the 3 year follow-up, most patients had encouraging recovery of sensory function in the hand but motor function of the forearm and hand muscles was rather poor. Acceptable motor function was found in only 50 to 60% of the patients who were younger than 18 years.

Journal ArticleDOI
TL;DR: It was concluded that the penetration of commercial bleaching products was different even though the products were labeled as having the same 10% carbamide peroxide.
Abstract: PURPOSE Vital tooth bleaching has become a popular procedure for whitening teeth. Most home bleaching products contain 10% carbamide peroxide. The purpose of this in vitro study was to measure the quantity of hydrogen peroxide that reaches the pulp chamber from three carbamide peroxide products: Opalescence, Sparkle, and Rembrandt. MATERIALS AND METHODS Seventy roots of extracted premolars were amputated approximately 3 mm apical to the cementoenamel junction, and the pulp tissues were removed. They were divided into three experimental groups (n = 20) and a control group of 10 teeth. An acetate buffer solution was placed in the pulp chamber before the crown was exposed to the bleaching agent at 37 degrees C for 25 minutes. The buffer solution was removed and reacted with leukocrystal violet and horseradish peroxidase. The optical density of blue color that developed was measured at a wavelength of 596 nm and read from a standard curve for hydrogen peroxide quantity. RESULTS The measured amounts of hydrogen peroxide were 3.605 +/- 1.405, 1.282 +/- 0.762, and 0.339 +/- 0.251 micrograms for the Opalescence, Sparkle, and Rembrandt groups, respectively. A statistically significant difference in the hydrogen peroxide levels was observed by analysis of variance (p < .05) among the three groups. It was concluded that the penetration of commercial bleaching products was different even though the products were labeled as having the same 10% carbamide peroxide. CLINICAL SIGNIFICANCE Carbamide peroxide penetration to the pulp varies significantly for various commercial bleaching products. This may result in different levels of tooth sensitivity or bleaching efficacy.

Journal ArticleDOI
TL;DR: It is suggested that hemoglobin E trait may ameliorate the course of acute falciparum malaria.
Abstract: To determine if hemoglobin E trait influences the course of acute malaria, adults hospitalized for the treatment of symptomatic infection with Plasmodium falciparum were studied retrospectively. Forty-two patients with hemoglobin E trait were compared with 175 reference subjects who did not have hemoglobin E, b-thalassemia, glucose-6-phosphate dehydrogenase deficiency, or a-thalassemia. One patient (2.4%) with hemoglobin E trait had a severe complication of malaria by World Health Organization criteria (cerebral malaria), while 32 subjects in the reference group (18.3%) had one or more severe complications: cerebral malaria (n 5 ), hyperparasitemia ( ), renal failure ( ), and severe anemia ( ) ( after 18 n 5 16 n 5 10 n 5 1 P 5 .044 adjustment for ethnic categories). The estimated odds of severe complications in the reference subjects were 6.9 times the odds in patients with hemoglobin E trait (95% confidence interval, 1.2‐146.4). These results suggest that hemoglobin E trait may ameliorate the course of acute falciparum malaria. The most common single gene disorders known are abnormalities affecting the synthesis or structure of hemoglobin, the thalassemias and hemoglobinopathies. Geographic overlap in the historical distributions of Plasmodium falciparum, the thalassemias and hemoglobinopathies, both globally and locally, provides compelling circumstantial evidence that these red blood cell abnormalities protect against malarial infection, but neither the mechanism nor the clinical features of this protection have been characterized. In parts of Thailand, where malaria is endemic and P. falciparum is the most drug-resistant in the world, the population has some of the highest known frequencies of thalassemias and hemoglobinopathies. The distribution of a- and b-thalassemia and of hemoglobins E and Constant Spring vary from region to region and among different ethnic groups [1]. About 30%‐40% of the population are carriers of at least one of these abnormal genes. In a study of 2806 persons in Phitsanulok, a province in the southern part of northern Thailand, the overall prevalence of hemoglobinopathies was 39%, and the prevalence of hemoglobin E was 25% [2]. Among 985 neonates in Bangkok, hemoglobin E was present in 18.7% and hemoglobin Barts (g4)‐designated a-thalassemia in 25.2%