Mahidol University

About: Mahidol University is a education organization based out in Bangkok, Nakhon Pathom, Thailand. It is known for research contribution in the topics: Population & Malaria. The organization has 23758 authors who have published 39761 publications receiving 878781 citations.

Causes of acute, undifferentiated, febrile illness in rural Thailand: results of a prospective observational study

Abstract: The adult patients who, between July 2001 and June 2002, presented at any of five hospitals in Thailand with acute febrile illness in the absence of an obvious focus of infection were prospectively investigated Blood samples were taken from all of the patients and checked for aerobic bacteria and leptospires by culture In addition, at least two samples of serum were collected at different times (on admission and 2-4 weeks post-discharge) from each patient and tested, in serological tests, for evidence of leptospirosis, rickettsioses, dengue and influenza The 845 patients investigated, of whom 661 were male, had a median age of 38 years and a median duration of fever, on presentation, of 35 days Most (765%) were agricultural workers and most (683%) had the cause of their fever identified, as leptospirosis (369%), scrub typhus (199%), dengue infection or influenza (107%), murine typhus (28%), Rickettsia helvetica infection (13%), Q fever (1%), or other bacterial infection (12%) The serological results indicated that 103 (122%) and nine (1%) of the patients may have had double and triple infections, respectively Leptospirosis and rickettsioses, especially scrub typhus, were thus found to be major causes of acute, undifferentiated fever in Thai agricultural workers

Hemoglobinopathies in Southeast Asia: Molecular Biology and Clinical Medicine

Abstract: Thalassemia (thal) and hemoglobinopathies are widespread, recessive inherited diseases. Approximately 250 million people (4.5% of the world population) carry abnormal hemoglobin (Hb) genes. Southeast Asia consists of 10 countries, i.e. Brunei, Cambodia, Indonesia, Laos, Malaysia, Myanmar, the Philippines, Singapore, Thailand, and Vietnam, with a total population of more than 400 million. In most of these countries the population is ethnically heterogeneous. Thalassemias are common in Southeast Asia. α-Thalassemias are very prevalent, attaining frequencies of 20–40%. β-Thal, Hb Constant Spring (CS) and Hb E are also common, the latter attaining a frequency as high as 50–60% among certain populations (1). Abnormal genes in different combinations lead to more than 60 different thalassemic syndromes. The thalassemia disorders were originally confined to the tropics and subtropics. However, Southeast Asians are now scattered around the world and have carried with them most of the complex thalassemic conditions...

Proinflammatory Cytokines and Chemokines in Humans with Japanese Encephalitis

Abstract: Background. Japanese encephalitis virus (JEV) the mosquito-borne flavivirus annually causes an estimated 35000-50000 encephalitis cases and 10000-15000 deaths in Asia and there is no antiviral treatment. The role played by the immune response in determining the outcome of human infection with JEV is poorly understood although in animal models of flavivirus encephalitis unregulated proinflammatory cytokine responses can be detrimental. Methods. We studied the innate cellular and humoral immune responses in 118 patients infected with JEV of whom 13 (11%) died. Results. Levels of interferon (IFN)-a the proinflammatory cytokine interleukin (IL)-6 and the chemokine IL-8 were all higher in the cerebrospinal fluid (CSF) of the nonsurvivors than of the survivors (P = .04 P = .006 and P = .04 respectively) as were both the IL- 6:IL-4 ratio in CSF (a marker of the balance of pro- and anti-inflammatory cytokines) and the level of the chemokine RANTES (regulated on activation normally T cell expressed and secreted) in plasma (P = .03). In contrast levels of immunoglobulin (Ig) M and IgG in CSF and of IgM in plasma were higher in the survivors (P = .035 P = .003 and P = .009 respectively). Levels of IFN-? and nitric oxide did not vary with outcome. Conclusions. During JEV infection elevated levels of proinflammatory cytokines and chemokines are associated with a poor outcome but whether they are simply a correlate of severe disease or contribute to pathogenesis remains to be determined. (authors)

Dengue 2 PDK-53 Virus as a Chimeric Carrier for Tetravalent Dengue Vaccine Development

Abstract: Attenuation markers of the candidate dengue 2 (D2) PDK-53 vaccine virus are encoded by mutations that reside outside of the structural gene region of the genome. We engineered nine dengue virus chimeras containing the premembrane (prM) and envelope (E) genes of wild-type D1 16007, D3 16562, or D4 1036 virus within the genetic backgrounds of wild-type D2 16681 virus and the two genetic variants (PDK53-E and PDK53-V) of the D2 PDK-53 vaccine virus. Expression of the heterologous prM-E genes in the genetic backgrounds of the two D2 PDK-53 variants, but not that of wild-type D2 16681 virus, resulted in chimeric viruses that retained PDK-53 characteristic phenotypic markers of attenuation, including small plaque size and temperature sensitivity in LLC-MK2 cells, limited replication in C6/36 cells, and lack of neurovirulence in newborn ICR mice. Chimeric D2/1, D2/3, and D2/4 viruses replicated efficiently in Vero cells and were immunogenic in AG129 mice. Chimeric D2/1 viruses protected adult AG129 mice against lethal D1 virus challenge. Two tetravalent virus formulations, comprised of either PDK53-E- or PDK53-V-vectored viruses, elicited neutralizing antibody titers in mice against all four dengue serotypes. These antibody titers were similar to the titers elicited by monovalent immunizations, suggesting that viral interference did not occur in recipients of the tetravalent formulations. The results of this study demonstrate that the unique attenuation loci of D2 PDK-53 virus make it an attractive vector for the development of live attenuated flavivirus vaccines.

A Decade of Gamma-Ray Bursts Observed by Fermi-LAT: The Second GRB Catalog

Abstract: The Large Area Telescope (LAT) aboard the Fermi spacecraft routinely observes high-energy emission from gamma-ray bursts (GRBs). Here we present the second catalog of LAT-detected GRBs, covering the first 10 yr of operations, from 2008 to 2018 August 4. A total of 186 GRBs are found; of these, 91 show emission in the range 30–100 MeV (17 of which are seen only in this band) and 169 are detected above 100 MeV. Most of these sources were discovered by other instruments (Fermi/GBM, Swift/BAT, AGILE, INTEGRAL) or reported by the Interplanetary Network (IPN); the LAT has independently triggered on four GRBs. This catalog presents the results for all 186 GRBs. We study onset, duration, and temporal properties of each GRB, as well as spectral characteristics in the 100 MeV–100 GeV energy range. Particular attention is given to the photons with the highest energy. Compared with the first LAT GRB catalog, our rate of detection is significantly improved. The results generally confirm the main findings of the first catalog: the LAT primarily detects the brightest GBM bursts, and the high-energy emission shows delayed onset as well as longer duration. However, in this work we find delays exceeding 1 ks and several GRBs with durations over 10 ks. Furthermore, the larger number of LAT detections shows that these GRBs not only cover the high-fluence range of GBM-detected GRBs but also sample lower fluences. In addition, the greater number of detected GRBs with redshift estimates allows us to study their properties in both the observer and rest frames. Comparison of the observational results with theoretical predictions reveals that no model is currently able to explain all results, highlighting the role of LAT observations in driving theoretical models.