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Publication Open Access Spatial distribution of potentially toxic trace elements of agricultural soils in the lower central plain of Thailand after the 2011 flood(2014-06) Aksarapak Pongpom; Kampanad Bhaktikul; Worachart Wisawapipat; Piyakarn Teartisup; Kampanad Bhaktikul; Mahidol University. Faculty of Environment and Natural Resource StudiesPublication Open Access การประเมินความเสี่ยงทางสุขภาพในการบริโภคน้ำประปาที่ปนเปื้อนโลหะหนัก : กรณีศึกษาระบบผลิตน้ำประปาหมู่บ้านถ้ำลา ตำบลลานข่อย อำเภอป่าพะยอม จังหวัดพัทลุง(2553) ธนาวัฒน์ รักกมล; ปุญญพัฒน์ ไชยเมล์; สมเกียรติยศ วรเดช; ชีระวิทย์ รัตนพันธ์; มหาวิทยาลัยมหิดล. สถาบันพัฒนาการสาธารณสุขอาเซียน; มหาวิทยาลัยทักษิณ. คณะวิทยาศาสตร์สุขภาพและกีฬาcollected from the beginning, middle and end of the pipeline. Water samples were also collected at different times, in the rainy (November, 2008) and dry seasons (May, 2009). The samples were then investigated for elements of the following nine heavyPublication Open Access Ethnoveterinary medicine based on Ayurveda plants(2012) Sookruetai Boonmasawai; Mahidol University. Faculty of Veterinary Science. Department of Pre-clinic and Applied Animal ScienceTraditional plants used for medicine exist for several thousand years ago in India to solve human health problems. The Ayurveda concept involved in the balancing of five basic elements including earth, water, fire, air, and space (ether) becausePublication Open Access Subpopulations of Staphylococcus aureus clonal complex 121 are associated with distinct clinical entities.(2013) Kurt, Kevin; Rasigade, Jean-Philippe; Laurent, Frederic; Goering, Richard V; Zˇemlicˇkova, Helena; Machova, Ivana; Struelens, Marc J.; Zautner, Andreas E.; Holtfreter, Silva; Broker, Brarbaa; Ritchie, Stephen; Reaksmey, Sin; Direk Limmathurotsakul; ดิเรก ลิ้มมธุรสกุล; Peacock, Sharon J.; Cuny, Christiane; Layer, Franziska; Witte, Wolfgang; Nubel, Ulrich; Nubel, Ulrich; Mahidol University. Faculty of Tropical Medicine.We investigated the population structure of Staphylococcus aureus clonal complex CC121 by mutation discovery at 115 genetic housekeeping loci from each of 154 isolates, sampled on five continents between 1953 and 2009. In addition, we pyro-sequenced the genomes from ten representative isolates. The genome-wide SNPs that were ascertained revealed the evolutionary history of CC121, indicating at least six major clades (A to F) within the clonal complex and dating its most recent common ancestor to the pre-antibiotic era. The toxin gene complement of CC121 isolates was correlated with their SNP-based phylogeny. Moreover, we found a highly significant association of clinical phenotypes with phylogenetic affiliations, which is unusual for S. aureus. All isolates evidently sampled from superficial infections (including staphylococcal scalded skin syndrome, bullous impetigo, exfoliative dermatitis, conjunctivitis) clustered in clade F, which included the European epidemic fusidic-acid resistant impetigo clone (EEFIC). In comparison, isolates from deep-seated infections (abscess, furuncle, pyomyositis, necrotizing pneumonia) were disseminated in several clades, but not in clade F. Our results demonstrate that phylogenetic lineages with distinct clinical properties exist within an S. aureus clonal complex, and that SNPs serve as powerful discriminatory markers, able to identify these lineages. All CC121 genomes harboured a 41-kilobase prophage that was dissimilar to S. aureus phages sequenced previously. Community-associated MRSA and MSSA from Cambodia were extremely closely related, suggesting this MRSA arose in the region.Publication Open Access Thermoregulatory correlates of nausea in rats and musk shrews(2014) Sukonthar Ngampramuan; Matteo Cerri; Flavia Del Vecchio; Corrigan, Joshua J; Amornrat Kamphee; Dragic, Alexander S; Rudd, John A; Romanovsky, Andrej A; Eugene Nalivaiko; Mahidol University. Institute of Molecular BiosciencesNausea is a prominent symptom and major cause of complaint for patients receiving anticancer chemo- or radiation therapy. The arsenal of anti-nausea drugs is limited, and their efficacy is questionable. Currently, the development of new compounds with anti-nausea activity is hampered by the lack of physiological correlates of nausea. Physiological correlates are needed because common laboratory rodents lack the vomiting reflex. Furthermore, nausea does not always lead to vomiting. Here, we report the results of studies conducted in four research centers to investigate whether nausea is associated with any specific thermoregulatory symptoms. Two species were studied: the laboratory rat, which has no vomiting reflex, and the house musk shrew (Suncus murinus), which does have a vomiting reflex. In rats, motion sickness was induced by rotating them in their individual cages in the horizontal plane (0.75 Hz, 40 min) and confirmed by reduced food consumption at the onset of dark (active) phase. In 100% of rats tested at three centers, postrotational sickness was associated with marked (~1.5°C) hypothermia, which was associated with a short-lasting tail-skin vasodilation (skin temperature increased by ~4°C). Pretreatment with ondansetron, a serotonin 5-HT3 receptor antagonist, which is used to treat nausea in patients in chemo- or radiation therapy, attenuated hypothermia by ~30%. In shrews, motion sickness was induced by a cyclical backand-forth motion (4 cm, 1 Hz, 15 min) and confirmed by the presence of retching and vomiting. In this model, sickness was also accompanied by marked hypothermia (~2°C). Like in rats, the hypothermic response was preceded by transient tail-skin vasodilation. In conclusion, motion sickness is accompanied by hypothermia that involves both autonomic and thermoeffector mechanisms: tail-skin vasodilation and possibly reduction of the interscapular brown adipose tissue activity. These thermoregulatory symptoms may serve as physiological correlates of nausea.Publication Open Access การจัดการกากไขมันจากบ่อดักไขมัน โดยกระบวนการทำปุ๋ยหมักร่วมกับดินค่ำและขี้เลื่อย(2558) วิรจิรวัส รวิชญทรัพย์; ธวัช เพชรไทย; ธนาศรี สีหะบุตร; วรพจน์ กนกกันฑพงษ์; Tawach Prechthai; Tanasri Sihabut; ธวัช เพชรไทย; มหาวิทยาลัยมหิดล. คณะสาธารณสุขศาสตร์. ภาควิชาวิทยาศาสตร์อนามัยสิ่งแวดล้อมกากไขมันเป็นกากของเสียอินทรีย์ที่โดยทั่วไปถูกกำาจัดจากถังดักไขมันที่ใช้ในระบบบำบัดน้ำเสีย ครัวเรือน ดังนั้นจึงควรถูกจัดการและกำจัดอย่างเหมาะสมเพื่อป้องกันปัญหาผลกระทบทางสิ่งแวดล้อมที่เกิดจากกากไขมันการทำเป็นปุ๋ยหมักร่วมกับวัสดุอื่นอาจสามารถนำามาใช้ในการจัดการของเสียประเภทนี้เพื่อที่จะนำกากไขมันกลับมาใช้ประโยชน์เป็นสารปรับสภาพดิน ดังนั้นงานวิจัยนี้จึงเพื่อศึกษาความเหมาะสมของกระบวนการทำาปุ๋ยหมักร่วมระหว่างกากไขมันดินค่ำและขี้เลื่อย วัสดุหมักถูกเตรียมโดยการผสมกากไขมัน 19.5 กิโลกรัม ร่วมกับดินค่ำ 12.0 กิโลกรัม และขี้เลื่อย 8.5 กิโลกรัม กระบวนการหมักดำเนินการในถังหมักที่มีการพลิกกลับกองปุ๋ยหมักเป็นระยะ จากนั้นระยะเวลาที่เหมาะสมและคุณภาพของปุ๋ยหมักถูกประเมินในการทดลองนี้ ผลการทดลองแสดงการเพิ่มขึ้นของอุณหภูมิในถังหมักที่ 63 องศาเซลเซียสก่อนที่จะลดลงเท่าอุณหภูมิภายนอกที่ภายในระยะเวลา 76 วัน ผลการวิเคราะห์คุณสมบัติของผลผลิตปุ๋ยหมักพบว่าค่าสัดส่วนคาร์บอนต่อไนโตรเจนและค่าพีเอชของปุ๋ยหมักเท่ากับ 17.5:1 และ 5.45 ตามลำาดับขณะที่ความเข้มข้นของกากไขมันและปริมาณอินทรีย์วัตถุเท่ากับ ร้อยละ 2.0 และ 35.0 โดยน้ำหนักนอกจากนี้ความเข้มข้นรวมของไนโตรเจน ฟอสฟอรัสและโพแทสเซียมในปุ๋ยหมักเท่ากับ ร้อยละ 1.2, 6.0 และ 28.8 โดยน้ำหนัก ตามลำาดับ สุดท้ายค่าดัชนีการงอกที่ร้อยละ 132.0 ที่พบในเมล็ดผักบุ้งจีน(Ipomceaaquatica Forsk) แสดงศักยภาพของปุ๋ยหมักจากกากไขมันร่วมกับดินค่ำและขี้เลื่อยในการใช้เป็นสารปรับสภาพดินPublication Open Access Climate induces seasonality in pneumococcal transmission.(2015-06) Numminen, Elina; Chewapreecha, Claire; Turner, Claudia; Goldblatt, David; Nosten, Francois; Bentley, Stephen D.; Turner, Paul; Corander, Jukka; Numminen, Elina; Mahidol University. Faculty of Tropical Medicine. Shoklo Malaria Research Unit, Mahidol-Oxford Tropical Medicine Research Unit.Streptococcus pneumoniae is a significant human pathogen and a leading cause of infant mortality in developing countries. Considerable global variation in the pneumococcal carriage prevalence has been observed and the ecological factors contributing to it are not yet fully understood. We use data from a cohort of infants in Asia to study the effects of climatic conditions on both acquisition and clearance rates of the bacterium, finding significantly higher transmissibility during the cooler and drier months. Conversely, the length of a colonization period is unaffected by the season. Independent carriage data from studies conducted on the African and North American continents suggest similar effects of the climate on the prevalence of this bacterium, which further validates the obtained results. Further studies could be important to replicate the findings and explain the mechanistic role of cooler and dry air in the physiological response to nasopharyngeal acquisition of the pneumococcus.Publication Open Access Construction of Bordetella pertussis strains with enhanced production of genetically-inactivated Pertussis Toxin and Pertactin by unmarked allelic exchange(2012) Wasin Buasri; Attawut Impoolsup; Chuenchit Boonchird; Anocha Luengchaichawange; Pannipa Prompiboon; Petre, Jean; Watanalai Panbangred; Mahidol University. Faculty of Science. Department of BiotechnologyBackground: Acellular Pertussis vaccines against whooping cough caused by Bordetella pertussis present a muchimproved safety profile compared to the original vaccine of killed whole cells. The principal antigen of acellular Pertussis vaccine, Pertussis Toxin (PT), must be chemically inactivated to obtain the corresponding toxoid (PTd). This process, however, results in extensive denaturation of the antigen. The development of acellular Pertussis vaccines containing PTd or recombinant PT (rPT) with inactivated S1, Filamentous Hemagglutinin (FHA), and Pertactin (PRN) has shown that the yield of PRN was limiting, whereas FHA was overproduced. To improve antigen yields and process economics, we have constructed strains of Bordetella pertussis that produce enhanced levels of both rPT and PRN. Results: Three recombinant strains of Bordetella pertussis were obtained by homologous recombination using an allelic exchange vector, pSS4245. In the first construct, the segment encoding PT subunit S1 was replaced by two mutations (R9K and E129G) that removed PT toxicity and Bp-WWC strain was obtained. In the second construct, a second copy of the whole cluster of PT structural genes containing the above mutations was inserted elsewhere into the chromosome of Bp-WWC and the Bp-WWD strain was obtained. This strain generated increased amounts of rPT (3.77 ± 0.53 μg/mL) compared to Bp-WWC (2.61 ± 0.16 μg/mL) and wild type strain (2.2 μg/mL). In the third construct, a second copy of the prn gene was inserted into the chromosome of Bp-WWD to obtain Bp-WWE. Strain Bp-WWE produced PRN at 4.18 ± 1.02 μg/mL in the cell extract which was about two-fold higher than Bp-WWC (2.48 ± 0.10 μg/mL) and Bp-WWD (2.31 ± 0.17 μg/mL). Purified PTd from Bp-WWD at 0.8-1.6 μg/well did not show any toxicity against Chinese hamster ovary (CHO) cell whereas purified PT from WT demonstrated a cell clustering endpoint at 2.6 pg/well. Conclusions: We have constructed Bordetella pertussis strains expressing increased amounts of the antigens, rPT or rPT and PRN. Expression of the third antigen, FHA was unchanged (always in excess). These strains will be useful for the manufacture of affordable acellular Pertussis vaccines.Publication Open Access Pandemic influenza H1N1 2009 in Thailand(2012) Aronrag Meeyai; Ben Cooper; Richard Coker; Wirichada Pan-ngum; Pasakorn Akarasewi; Sopon Iamsirithaworn; อรุณรักษ์ คูเปอร์ มีใย; Aronrag Meeyai; Mahidol university. Faculty of Public Health. Department of Epidemiology; Mahidol university. Faculty of Tropical Medicine. Department of Tropical Hygiene; Mahidol university. Faculty of Tropical Medicine. Mahidol-Oxford Tropical Medicine Research UnitBackground: Developing a quantitative understanding of pandemic influenza dynamics in South- East Asia is important for informing future pandemic planning. Hence, transmission dynamics of influenza A/H1N1 were determined across space and time in Thailand. Methods: Dates of symptom onset were obtained for all daily laboratory-confirmed cases of influenza A/H1N1pdm in Thailand from 3 May 2009 to 26 December 2010 for four different geographic regions (Central, North, North-East, and South). These data were analysed using a probabilistic epidemic reconstruction, and estimates of the effective reproduction number, R(t), were derived by region and over time. Results: Estimated R(t) values for the first wave peaked at 1.54 (95% CI: 1.42-1.71) in the Central region and 1.64 (95% CI: 1.38-1.92) in the North, whilst the corresponding values in the North-East and the South were 1.30 (95% CI: 1.17-1.46) and 1.39 (95% CI: 1.32-1.45) respectively. As the R(t) in the Central region fell below one, the value of R(t) in the rest of Thailand increased above one. R(t) was above one for 30 days continuously through the first wave in all regions of Thailand. During the second wave R(t) was only marginally above one in all regions except the South. Conclusions: In Thailand, the value of R(t) varied by region in the two pandemic waves. Higher R(t) estimates were found in Central and Northern regions in the first wave. Knowledge of regional variation in transmission potential is needed for predicting the course of future pandemics and for analysing the potential impact of control measures.Publication Open Access Soil physicochemical status and nutrient management for paddy soils in the lower central plain of Thailand after the flood disaster in 2011(2014-06) Benjaporn Intorpetch; Worachart Wisawapipat; Chumlong Arunlertaree; Piyakarn Teartisup; Mahidol University. Faculty of Environment and Natural Resource StudiesThe soil fertility status were evaluated for 29 paddy soils in Phra Nakhon, Si Ayutthaya and Pathum Thani provinces, Thailand that had been affected by the flood disaster in 2011. The chemical fertility status of the soils in the flood affected areas was medium, which is relatively superior to the pre-flood condition. The available potassium in most soils was slightly larger (mean = 220 mg kg-1) than the values previously reported on these soils (mean = 188 mg kg-1). However, mean values of available phosphorus for most soils were rather small (7.5 mg kg-1), indicating a loss of phosphorus fertility and those farmers in the flood affected areas needed to apply additional phosphorus fertilizer in order to achieve satisfactory crop yields. Liming should also be used to minimize potential Al/metals toxicity and correct imbalances of plant nutrients. Several plant nutrients (NPK) and organic materials need to be regularly applied to maintain soil fertility levels at optimum values.