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This paper presents the integration of magnetic susceptibility measurements and whole-rock geochemical compositional and Nd–Sr isotopic ratio analyses for granite samples collected from the Ranong, Lam Pi, Ban Lam Ru, and Phuket granite bodies in the Western Granitoid Belt of Thailand. In addition, U–Pb dating was performed on zircons extracted from the samples. All samples are proper granites based on their mineralogical and geochemical characteristics. Two samples collected from the Lam Pi granite body were classified as magnetite-series and I-type. The remaining granite samples were classified as ilmenite-series and S- or A-type. Furthermore, all granites were classified as syn-collision granites. Excluding the magnetite-series samples from the Lam Pi granite body, the other samples exhibit enrichment in incompatible elements, such as Nb, Sn, Ta, Pb, Bi, Th, U, Ce, Rb, and Cs. Zircon U–Pb dating yielded ages of ca. 60 Ma for the magnetite-series granites from the Lam Pi granite body, whereas ages of 88–84 Ma were obtained for the other granite bodies. Initial Nd–Sr isotopic ratios indicate a higher contribution of mantle material in the Lam Pi magnetite-series granites and a higher contribution of continental crust material in the other granites. Based on these compositional and zircon U–Pb age data, it is inferred that the 88–84 Ma granites formed as a result of the thickening of the continental crust owing to the collision between the Sibumasu and the West Burma blocks. In contrast, the ca. 60 Ma Lam Pi magnetite-series granites are thought to have been generated via partial melting of the mantle wedge associated with the subduction of the Neo-Tethyan oceanic crust beneath the West Burma Block. [ABSTRACT FROM AUTHOR]

Introduction: Hepatocellular carcinoma (HCC) causes more than 200,000 women deaths annually. This study aimed to investigate the clinical features, provide prognostic factors for female patients with HCC, and performed a literature review on them in the Association of Southeast Asian Nations (ASEAN). Materials and Methods: We conducted a retrospective cohort study of female patients with HCC at Thammasat University Hospital, Thailand between January 2009 and January 2019. Furthermore, important aspects of female patients with HCC in the ASEAN published in PubMed and Scopus up to October 2020 were extensively reviewed. Results: A total of 187 female patients with HCC were included (mean age 65.7± 11.9 years). Elderly females were diagnosed with HCC at a more advanced stage than younger individuals (37.0% vs 23.2%, p=0.049, OR 1.94, 95% CI 1.00– 3.78) and the younger group had a significantly higher overall 2-year survival rate than the elderly group (65.0% vs 45.5%, p=0.03, OR 2.23, 95% CI 1.09– 4.57). Abdominal pain (HR 9.89, 95% CI 2.85– 34.38, p< 0.001), ascites at presentation (HR 2.77, 95% CI 1.11– 6.92, p=0.03), ruptured hepatoma (HR 14.68, 95% CI 12.60– 83.09, p=0.002), advanced-stage HCC (HR 9.74, 95% CI 1.89– 50.26; p=0.007), and serum hypoalbuminemia (HR 4.67, 95% CI 1.62– 13.50, p=0.004) were significantly associated with poor survival rate. From the ASEAN, a total of 543 females HCC patients from 6 studies were extensively reviewed. Chronic hepatitis B infection was among the pre-existing liver disease leading to HCC in ASEAN. HCC in females of the ASEAN occurred most often at an advanced age and had a grave prognosis. Conclusion: HCC affects a large number of females, especially in Thailand and the ASEAN, is diagnosed at an advanced stage and had a grave prognosis. Abdominal pain, ascites, ruptured HCC, advanced-stage HCC, and serum hypoalbuminemia are associated with poor prognosis. Early detection of HCC and prompt treatment in patients at risk could result in better survival outcomes. [ABSTRACT FROM AUTHOR]

Background: Gastric intestinal metaplasia (IM) is precancerous lesion of gastric cancer related to H. pylori infection. There has been limited data about IM and associated risk factors. This study aimed to determine risk factors related to development of IM to guide proper management. Methods: 1,370 patients undergoing UGI endoscopy at Thammasat University Hospital, Thailand were included between January 2018-August 2019. Patients' data including baseline characteristics, laboratory results, and histopathology from medical database were extensively reviewed. Immunohistochemical staining for p53 expression from gastric biopsies was also performed. Results: Overall H. pylori prevalence was 43.8%. Mean age was 60.7 years and 45% of whom were males. Chronic gastritis was observed in 1,064(77.7%) patients, while 223(16.3%) had IM. Of 223 patients with IM, 194(87%) patients had complete IM, while 29 (13%) had incomplete IM. In groups of complete and incomplete IM, current H. pylori infection rates were 66.5% and 58.6%, respectively. The BMI of incomplete IM group(27.4) was significantly higher than BMI of complete IM group (23.6). Overweight and obese patients (BMI ≥23 kg/m2) were significantly associated with higher risk for the development of incomplete IM (OR 3.25; 95%CI 1.14–9.27, p = 0.027). Males, age >50 years, and current H. pylori infection were significantly higher in IM than chronic gastritis group with OR 1.43 (95%CI 1.01–2.03, p = 0.048), OR 1.67 (95% CI 1.08–2.57, p = 0.021), and OR 3.14 (95% CI 2.29–4.30, p<0.001), respectively. During 20 months of study, there were 15 patients (1.1%) diagnosed with gastric cancer and 1-year survival rate was only 60%. Conclusions: Males, age >50 years, and current H. pylori infection are significant predictors for the presence of intestinal metaplasia. BMI might be beneficial for using as a predictive risk factor to reduce the development of incomplete intestinal metaplasia. H. pylori eradication could be an effective way to prevent the development of gastric precancerous lesions. [ABSTRACT FROM AUTHOR]

Background: There are few studies analyzed concurrently the prevalence and genotypes of Helicobacter pylori infection with the ancestor origins from different ethnics, especially with including minority groups. We recruited a total of 289 patients in MaeSot, Thailand (154 Thai, 14 Thai-Chinese, 29 Karen and 92 Hmong ethnics). The virulence genes and genealogy of the strains were determined by PCR-based sequencing. Results: Based on culture and histology/immunohistochemistry, the prevalence of H. pylori infection was 54.5% (158/289). Among 152 isolates cultured, the East-Asian-type cagA was predominant genotype among strains from Hmong, Thai-Chinese and Thai (96.0% [48/50], 85.7% [6/7] and 62.7% [47/75], respectively), whilst majority of strains from Karen had Western-type cagA (73.3% [11/15]). Patients infected with the East-Asian-type cagA strains had significantly higher activity and intestinal metaplasia in the antrum and activity in the corpus than those with Westerntype cagA (P = 0.024, 0.006 and 0.005, respectively). The multilocus sequencing typing analysis discriminated that most strains from Hmong and Thai-Chinese belonged to hspEAsia (92.0 and 85.7%, respectively), whereas strains from Karen predominantly possessed hpAsia2 (86.7%) and strains from Thai were classified into hspEAsia (45.2%) and hpAsia2 (31.1%). Conclusions: Helicobacter pylori genotypes were relatively different among ethnic groups in Thailand and were associated with the source of ancestor even living in a small rural town. Caution and careful check-up are required especially on Hmong ethnic associated with high prevalence of virulence genotypes of H. pylori. [ABSTRACT FROM AUTHOR]

Background: The risk to develop gastric cancer in Thailand is relatively low among Asian countries. In addition, the age-standardized incidence rate (ASR) of gastric cancer in Thailand varies with geographical distribution; the ASR in the North region is 3.5 times higher than that in the South region. We hypothesized that the prevalence of H. pylori infection and diversity of CagA phenotype contributes to the variety of gastric cancer risk in various regions of Thailand. Methods: We conducted a nationwide survey within Thailand. We determined H. pylori infection prevalence by detecting H. pylori, using histochemical and immunohistochemical methods. The anti-CagA antibody and anti-East-Asian type CagA antibody (α-EAS Ab), which showed high accuracy in several East Asian countries, were used to determine CagA phenotype. Results: Among 1,546 patients from four regions, including 17 provinces, the overall prevalence of H. pylori infection was 45.9% (710/1,546). Mirroring the prevalence of H. pylori infection, histological scores were the lowest in the South region. Of the 710 H. pylori-positive patients, 93.2% (662) were immunoreactive with the anti-CagA antibody. CagA-negative strain prevalence in the South region was significantly higher than that in other regions (17.9%; 5/28; p < 0.05). Overall, only 77 patients (11.6%) were immunoreactive with the α-EAS Ab. There were no differences in the α-EAS Ab immunoreactive rate across geographical regions. Conclusions: This is the first study using immunohistochemistry to confirm H. pylori infections across different regions in Thailand. The prevalence of East-Asian type CagA H. pylori in Thailand was low. The low incidence of gastric cancer in Thailand may be attributed to the low prevalence of precancerous lesions. The low incidence of gastric cancer in the South region might be associated with the lower prevalence of H. pylori infection, precancerous lesions, and CagA-positive H. pylori strains, compared with that in the other regions. [ABSTRACT FROM AUTHOR]

We investigated the sandstone used in the construction of the Khmer monuments situated upon and around the Khorat Plateau in north-east Thailand in order to clarify the provenance. The sandstones of the 22 investigated Khmer monuments can be classified into three groups. The sandstone of Group 1 is lithic and is derived mainly from the Khok Kruat Formation. This group includes the sandstone used at Phimai, Phnom Wan, Muang Khaek etc. The sandstone of Group 2 is siliceous and can be subdivided into three further groups. The sandstone of Group 2 is considered to have been derived from the Phu Phan, Phra Wihan or Sao Khua Formations. The sandstone used at Muang Tam, Phnom Rung, Sdok Kok Thom, Preah Vihear (Khao Phra Wihan), Narai Jaeng Waeng etc. belongs to Group 2. The sandstone of Group 3 is feldspathic and is correlated with the grey to yellowish-brown sandstone that is commonly used in the Angkor monuments in Cambodia. This sandstone is used at Wat Phu and Hong Nang Sida in Laos. The above results reveal that the choice of sandstone used for the Khmer monuments, including the Angkor monuments, was dictated by the surrounding geology. [ABSTRACT FROM AUTHOR]

Abstract: A comprehensive molecular epidemiological analysis was performed on highly pathogenic avian influenza (HPAI) viruses of the H5N1 subtype derived from poultry and wild bird during 2004–2007 in Thailand. Sequence analysis followed by phylogenetic analysis was applied to all eight segments of the viruses. Viruses belonging to clades 1 and 2.3.4 in the HA phylogenetic tree have been shown to circulate in Thailand. Our analysis revealed differential evolution of the HPAI viruses among clade 1 strains. Isolates from Phichit province in 2006 resided in two distinct branches, designated 1.p1 and 1.p2. A hemagglutination inhibition test with a panel of monoclonal antibodies demonstrated a possible antigenic drift between the Phichit isolates. Involvement of free-grazing duck practice in the area was discussed as a cause of the differential evolution among the Phichit isolates. A branch, designated 1-TGWB and consisting exclusively of isolates from zoological tigers and wild birds, was evident in all phylogenetic trees constructed in the study. The branch’s existence indicated that the HPAI viruses could have been maintained in the wild bird population for a certain period, although no involvement of wild birds in HPAI transmission to poultry was evident in this study. [Copyright &y& Elsevier]

Background Recent studies have revealed the existence of genetic diversity in swine influenza viruses (SIVs) in the world. In Thailand, there has been a little information on the molecular characteristics of the SIVs since the first isolation of viruses of H1N1 and H3N2 subtypes in the late 1970s. Our previous study demonstrated that Thai H1N1 SIVs possessed the classical swine H1 and avian-like swine N1 genes (Takemae et al., Proceedings of the Options for the Control of Influenza VI.2007;350–353). Objectives In the present study, we genetically characterized 12 SIVs including those of H1N1, H1N2 and H3N2 subtypes isolated between 2000 and 2005. Methods We determined the entire nucleotide sequences of the eight gene segments of those isolates. Results Phylogenetic analysis revealed the existence of nine distinct genotypes amongst the Thai SIVs. These genotypes arose from multiple introductions of classical swine, avian-like swine and human viruses. The existence of two distinct sublineages within classical swine H1 and NS, avian-like swine PA and M and human H3 and N2 genes of the Thai SIVs suggested that introduction of viruses of classical swine, avian-like swine and human origins occurred twice respectively into the Thai pig population. The predominance of avian-like swine genes amongst the Thai SIVs was evident. In particular, three polymerase (PB1, PB2 and PA) and matrix genes of avian-like swine origin were retained in all the Thai SIVs examined. Conclusions These observations may suggest that genes of avian-like swine lineages have some advantages to be maintained in pigs as seen in the SIVs established through multiple introductions in other regions. [ABSTRACT FROM AUTHOR]

The liver fluke infection-associated intrahepatic cholangiocarcinoma (ICC) is a major liver cancer in Northeast Thailand. The molecular basis of this ICC is poorly understood. To address possible roles of the DNA mismatch repair (MMR) system in ICC carcinogenesis, a fluorescence-labeling PCR/laser scanning technique with high sensitivity was employed to analyze genomic instability in the nuclear DNA (nDNA) and mitochondrial DNA (mtDNA) in 24 fresh and 13 formalin-fixed, paraffin-embedded tissues of ICC and their corresponding normal parts. Microsatellite instability (MSI) was assessed in nDNA, using 12 highly polymorphic loci including 5 Bethesda markers. These loci were mainly related to major MMR genes, hMSH2 and hMLH1. Also 3 (C)n and/or (C)n(A)n repeat instability at 1 noncoding region in the displacement-loop (D-loop) and 2 coding sequences in NADH dehydrogenase subunit 1 and subunit 5 gene in mtDNA were analyzed. MSI was only detected in 1 (2.7%), 6 (16.7%), 1 (2.9%), 1 (2.9%) or 2 (6.3%) out of 37, 36, 35, 35 or 32 cases at BAT-25, D2S123, D3S1611, D11S904 or D17S250, respectively. LOH was found at D3S1298, D3S1561, D5S346 and TP53 in 4 (18.2%) out of 22, 2 (18.2%) out of 11, 6 (33.3%) out of 18 and 3 (12.5%) out of 24 informative cases, respectively. In mtDNA, none except a single case out of the 37 (2.7%) exhibited repeat sequence instability in the D-loop. We conclude that the liver fluke infection-associated ICC in Thailand is classified as low frequency MSI or microsatellite stable type and that DNA MMR system, through hMSH2 and hMLH1 gene mutations, does not play a major role in its carcinogenesis. © 2003 Wiley-Liss, Inc. [ABSTRACT FROM AUTHOR]

The cooling of spaces in tropical regions, such as Southeast Asia, consumes a lot of energy. Additionally, rapid population and economic growth are resulting in an increasing demand for space cooling. The ground-source heat pump has been proven a reliable, cost-effective, safe, and environmentally-friendly alternative for cooling and heating spaces in various countries. In tropical countries, the presumption that the ground-source heat pump may not provide better thermal performance than the normal air-source heat pump arises because the difference between ground and atmospheric temperatures is essentially low. This paper reports the potential use of a ground-source heat pump with horizontal heat exchangers in a tropical country—Thailand. Daily operational data of two ground-source heat pumps and an air-source heat pump during a two-month operation are analyzed and compared. Life cycle cost analysis and CO2 emission estimation are adopted to evaluate the economic value of ground-source heat pump investment and potential CO2 reduction through the use of ground-source heat pumps, in comparison with the case for air-source heat pumps. It was found that the ground-source heat pumps consume 17.1% and 18.4% less electricity than the air-source heat pump during this period. Local production of heat pumps and heat exchangers, as well as rapid regional economic growth, can be positive factors for future ground-source heat pump application, not only in Thailand but also southeast Asian countries. [ABSTRACT FROM AUTHOR]

Subsurface utilization in the tropical regions as a heat sink for ground source heat pumps (GSHPs) leads to thermal buildup in the long term, resulting in the decreased energy performance. However, the applicability of the GSHP in these regions has never been investigated based on the predicted heat sink temperature over a lifetime. This study aimed to evaluate the energy performance of a large-scale GSHP system in representative building models in Thailand based on operating conditions derived from a predicted 50-year heat sink temperature. The proposed system combines a GSHP and an air-source heat pump (ASHP), and, in one scenario, the GSHP also supplies hot water. The results confirm that the combined system achieves a higher efficiency than that of an ASHP system alone, and GSHP supplying hot water realizes substantial energy-saving. However, limitations on the annual GSHP operation hours are essential, resulting in low energy-saving performance for cooling dominated facilities. Further improvements are expected by mitigating the thermal interactions among each borehole heat exchanger. [ABSTRACT FROM AUTHOR]

Abstract: In Thailand, highly pathogenic avian influenza (HPAI) viruses of subtype H5N1 had been isolated from various wild birds during the HPAI outbreak in poultries. In this study, we examined the pathogenicity of two wild bird isolates (A/Pigeon/Thailand/VSMU-7-NPT/2004; Pigeon04 and A/Tree sparrow/Ratchaburi/VSMU-16-RBR/2005; T.sparrow05) in mice. They showed similar replication in several organs and lethal outcome. However, on day 3 post-infection, Pigeon04 induced mRNA expression of proinflammatory cytokines (IL6 and TNFα) and MIP-2, neutrophil chemoattractant, in the lungs, resulting in severe pneumonia that was accompanied by neutrophil infiltration. In contrast, on day 7 post-infection, T.sparrow05 induced the expression of several cytokines to a greater extent than Pigeon04; it also potently induced mRNA expression of several cytokines in brains of the infected mice that triggered frequent inflammatory events. In sum, our study demonstrated that two HPAI viruses induced different host responses, despite having similar replications, resulting in lethal outcome in mice. [Copyright &y& Elsevier]

Abstract: Highly pathogenic avian influenza (HPAI) viruses of the H5N1 subtype have caused several rounds of outbreaks in Thailand. In this study, we used 3 HPAI viruses isolated in Thailand in January 2004 from chicken, quail, and duck for genetic and pathogenetic studies. Sequence analysis of the entire genomes of these isolates revealed that they were genetically similar to each other. Chickens, quails, domestic ducks, and cross-bred ducks were inoculated with these isolates to evaluate their pathogenicity to different host species. A/chicken/Yamaguchi/7/04 (H5N1), an HPAI virus isolated in Japan, was also used in the chicken and quail studies for comparison. All four isolates were shown to be highly pathogenic to chickens and quails, with 100% mortality by 106 EID50 inoculants of the viruses. They caused sudden death in chickens and quails within 2–4 days after inoculation. The mean death times (MDT) of quails infected with the Thai isolates were shorter than those of chickens infected with the same isolates. Mortality against domestic and cross-bred ducks ranged from 50 to 75% by intranasal inoculation with the 106 EID50 viruses. Neurological symptoms were observed in most of the inoculated domestic ducks and appeared less severe in the cross-bred ducks. The MDTs of the ducks infected with the Thai isolates were 4.8–6 days post-inoculation. Most of the surviving ducks infected with the Thai isolates had sero-converted until 14dpi. Our study illustrated the pathobiology of the Thai isolates against different poultry species and would provide useful information for improving control strategies against HPAI. [Copyright &y& Elsevier]