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Adrenal cysts are rare; most lack endocrinologic activity and do not produce clinical symptoms. The present case is the first to be reported with both an adrenal cyst and a functioning adenoma present ipsilaterally. This 39-year-old male with hypertension was diagnosed as having primary aldosteronism as reflected by hypokalemia and an excess plasma aldosterone concentration (PAC). However, examination by computed tomography revealed a grossly enlarged left adrenal gland with a cyst-like lesion. The right adrenal appeared normal. At surgery, an adenoma and a cyst were found to coexist in the left adrenal cortex. The cyst fluid contained three times the amount of aldosterone present in plasma, less than in previous reports, and was considered to lack endocrinologic activity. Following a left adrenectomy, the patient's blood pressure, serum potassium concentration, and PAC all normalized without the need for medical treatment.

In 30-40% of patients with primary aldosteronism owing to adenoma, hypertension is not relieved even though a hyper-functioning adenoma has been completely removed. The purpose of this study is to determine whether the prognosis of hypertension can be evaluated pre-operatively in patients with primary aldosteronism. Thirteen patients (6 men, 7 women; 47 +/- 9 years old) with primary aldosteronism were studied and adrenalectomy was performed in all cases. The success of the operation was confirmed by the normalization of plasma renin activity (PRA), plasma aldosterone concentration (PAC) and serum potassium. Eight patients, 3 men and 5 women, whose blood pressure (BP) was reduced to below 140mmHg systolic and 90mmHg diastolic at one year after the operation were classified as "group N" and the other 5 cases, 3 men and 2 women, remained hypertensive and were classified as "group H". There were no significant differences in the age of the patients, duration of hypertension, pretreatment mean BP and severity of hypertension between the two groups. Thus, it is doubtful that the lack of improvement of hypertension is due to the irreversible damage of the small arteries. Although pretreatment BP was similar in the two groups, systolic BP after the administration of 200mg per day of spironolactone for one week was significantly reduced in group N, but not in group H. Moreover, a significant correlation was found between mean BP after treatment with spironolactone and post-operative mean BP in all subjects. Pretreatment PRA was significantly lower in group H.(ABSTRACT TRUNCATED AT 250 WORDS)

受精卵移植(MOET)によって造成される肉用牛小集団において,優性効果が遺伝的改良量に及ぼす影響を遺伝子効果を考慮した選抜交配シミュレーションを用いて検討した.集団は各世代60頭からなるとし,世代は重複するとした.対象形質は相加的および優性効果を持つ64遺伝子座によって支配され,また両性で観察されるとした.遺伝子頻度の影響を確かめるために形質に正の効果を持つ遺伝子の頻度を0.2,0.5および0.8とし,広義の遺伝率を0.6とした.また各胚提供雌は1世代につき4頭の後代を生産するとした.雄5頭,雌15頭をアニマルモデルBLUP法による育種価予測値によって選抜し,この選抜交配を6世代にわたって行なった.育種価は相加的効果のみを考慮するモデルと優性効果をも考慮するモデルによって予想した.その結果,MOETのように個体間により多くの優性血縁関係が生じる集団において育種価を予測する場合,優性効果をも考慮できるモデルによって,正確度が高く,偏りの小さな予想値が得られる傾向が認められ,このことは中程度の遺伝子頻度,すなわち新たに交雑などにより造成された集団で育種価予測値による選抜を開始するような場合には特に顕著であった.また,このモデルによる育種価予測値を用いた選抜の結果,わずかながら高い遺伝的改良量が得られることが明らかとなり,MOETによる集団での遺伝的評価において,計算時間や費用の制約がなければ優性効果を考慮する必要のあることが示唆された.

The objectives of this study were to detect effective genetic polymorphisms of bovine growth hormone (bGH) gene associated with calf weight in Japanese Black cattle. Fifty-eight sires and 47 breeding cows were used to detect the polymorphisms in exons by single-strand conformation polymorphism (SSCP). Four homozygous and six heterozygous SSCP genotypes were identified in exon 5. Although each single nucleotide polymorphism (SNP) had been reported, these genotypes were caused by three SNPs at the nucleotide positions 2141, 2277 and 2291. Four haplotypes C-C-A, G-C-A, C-C-C and G-T-A were newly identified. It was suggested that other haplotypes not detected in this study may not exist, considering the allele frequencies reported in Bos taurus and Bos indicus, and the migrating process of native Japanese cattle. Thereafter, we examined associations between the detected polymorphic sites in exon 5 by PCR - restriction fragment length polymorphism and calf weight using 53 breeding dams and 135 calves. The birth weights of calves with haplotype G-C-A are significantly lighter and calves' weights produced by cows with such haplotype are also lighter at 30 days old, using regression analysis. Although further research is necessary, these results may serve as a useful criterion to select breeding stocks, especially in maternal abilities.

Objectives: This study examined the association between the serum leptin level and body mass index (BMI) and the effects of urbanization and polymorphisms of leptin (LEP) or leptin receptor (LEPR) genes on the leptin level in three Solomon Islands populations. Methods: A Melanesian population living in a remote area (participants: 106 males and 106 females, ages: 18–74 years), a Melanesian population in an urban area (89 and 94, 18–79 years), and a Micronesian population who migrated to a peri-urban area in the 1960s (84 and 69, 18–71 years) were studied. Anthropometric and serum leptin measurements and genotyping for LEP G-2548A and LEPR K109R and Q223R were performed. Results: The prevalence of obesity (BMI ≥ 30 kg/m2) was the highest in the Micronesian population (30.1%), followed by the urban (18.6%) and the rural (2.4%) Melanesian population. The serum leptin concentration was the highest in the urban Melanesian, followed by the Micronesian and the rural Melanesian populations (P < 0.05). Interestingly, the parameter coefficients of the leptin concentrations on the BMIs were nearly identical in the urban and rural Melanesians after adjusting for age and gender. The LEPR 223Q/Q genotype was associated with an increased leptin level only in the Micronesian population after adjusting for BMI (P = 0.0008 and 0.0016 referenced to the Q/R and the R/R types, respectively). Conclusions: These observations suggest that the increase in obesity in the Micronesians had a genetic component while that in Melanesians might have been related with the urbanization. Am. J. Hum. Biol., 2011. © 2010 Wiley-Liss, Inc.

Epstein–Barr virus (EBV) is ubiquitous in the human population and seroepidemiological studies have revealed that more than 90 % of adults are infected with the virus in Thailand. It has been suggested that latent membrane protein 1 (LMP1) variants may differ in their tumorigenicity and geographical localization. The distribution of LMP1 variants of EBV in the Thai population was studied. A total of 259 LMP1 sequences from ten Thai ethnic groups (Lahu, Lisu, Shan, Red Karen, White Karen, Hmong, Akha, Mlabri, Moken and Urak Lawoi) were studied using direct PCR sequencing. Nucleotide sequences corresponding to the C terminus of the LMP1, including previously published sequences from central and southern Thais, were used in the phylogenetic analysis. Five strains – the B95-8 prototype, China 1, China 2, Mediterranean (Med) and SEA 2 – were identified in ethnic groups in Thailand. The major strain and the distribution pattern differed by group and location. When the ethnic groups were classified by linguistic group, the prevalence of the SEA 2 strain was significantly different between Austro-Thais and other linguistic groups (P=0.0001), whereas, among Tibeto-Burman linguistic groups, the prevalence of the Med strain was different between matrilocal and patrilocal groups (P=0.0245). The distribution of LMP1 strains in ethnic minorities in Thailand is associated with ethnogeographical factors and the social/marriage system. This study thus provides evidence for the importance of interactions between populations in virus diversity.

Nine male chimpanzees originally reared in solitary cages were set up to form a group. Plasma viral load of the lymphocryptovirus (LCV) of chimpanzee [Epstein–Barr virus chimpanzee (EBVcmp)] was measured by real-time PCR. In the group formation (Form) period, the first-ranking male showed an imminent increase in plasma EBVcmp load compared with 1 week before (pre-Form) and 3 months after (post-Form) group formation. Other upper-ranking males such as the second-, third- and fourth-male also showed the highest level of viral load in the Form period. The kinetics of EBVcmp load in the Form period were statistically different from other periods (against pre-Form, t=−4.878, Pt=6.434, Pt=−1.557, P=0.12). Reactivation of LCV (EBV) as an immunological stress marker for humans might also be applied to chimpanzees.

Oral squamous cell carcinoma (OSCC) is highly prevalent in southeastern Asia suggesting that region-specific environmental and biological factors contribute to the development of this cancer. Exposure to oral carcinogens (i.e. betel quid) and pathogenic agents (i.e. papilloma virus) is common among individuals that develop OSCC in countries such as Thailand, India etc. However, not all individuals with such exposures develop the disease suggesting that other factors further increase susceptibility to OSCC. It is therefore plausible that functional variants in DNA repair genes and/or genes controlling inflammation and immunological response play a role in determining susceptibility to OSCC. Previous studies (including ours) have found an association between variants in DNA repair genes and increased susceptibility to OSCC. By extension, the current study examined the association between SNPs in genes encoding proteins involved in inflammation and immunomodulation (IL1alpha, IL1beta, IL8, TNFalpha) and OSCC. A total of 107 cases and 157 controls were analyzed. OSCC cases were more likely to carry the "T" allele at the IL1alpha(+4845) SNP than controls (OR=2.0, 1.0-4.4). OSCC cases that smoke and drink were more likely to carry either the "T" allele at the IL1beta(+3953) SNP (OR=10.4, 1.1-93.2) or the "C" allele at the TNFalpha(-1031) SNP (OR=3.4, 1.0-11.4) than controls. These results support the hypothesis that variants in inflammatory or immunomodulatory genes influence susceptibility to OSCC in Thailand. Larger studies are needed to confirm these results and more importantly to properly investigate the complex interactions among genetic variants in DNA repair and inflammation and other non-genetic susceptibility factors. In addition, laboratory experiments designed to determine the functional properties of the genetic variants are needed.

To evaluate the relationships between genetic polymorphisms of the GSTs (GSTM1 and GSTT1) and cervical cancer, the null genotype of each gene was studied in squamous cell cervical cancer (SCCA) patients (n=90) and controls (n=94) in Northeast Thailand. The prevalence of the GSTM1-null genotype in the controls and SCCA patients was 59.6% and 60.0%, respectively, whereas those of the GSTT1-null genotype in the control and SCCA patients was 40.4% and 46.7%, respectively. Neither of the GST-null genotypes increased the risk for SCCA (p0.05); however, the combination of the GSTM-1 and GSTT1-null genotypes showed a non-significant trend for an increased risk for developing cervical cancer with an adjusted OR of 2.7 (95%CI=0.8-9.0, p=0.10). Genetic polymorphisms of GSTM1 and GSTT1 were not significant risk factors for cervical cancer in either tobacco-smokers or non-smokers. A different contribution of the GST genotype to cancer risk may be attributed to a different, as yet undefined, property of the enzymes.

Aim: Calcium channel blockers (CCBs) inhibit the migration of vascular smooth muscle cells (VSMC) by mechanisms that remain poorly understood. The purpose of the present study was to characterize the signaling mechanisms by which CCBs inhibit VSMC migration.Methods and Results: Nifedipine potently inhibited platelet-derived growth factor (PDGF)-induced chemotaxis, collagen I-induced haptotaxis, and wound-induced migration of human aortic VSMC. In addition, nifedipine inhibited PDGF-induced membrane ruffling and lamellipodium formation. PDGF-induced VSMC migration was significantly inhibited by PP2, a selective inhibitor of the Src kinase family, and was also significantly inhibited by the expression of kinase-inactive Src, suggesting that Src is required for VSMC migration. Nifedipine also inhibited PDGF-induced Src activation (by 60±4% with 30 µM) and tyrosinephosphorylation of Cas, paxillin, and cortactin, which are actin-associated substrates of Src. RNA interference-induced knockdown of the Ca2+-dependent tyrosine kinase, Pyk2, resulted in inhibition of PDGF-induced Src activation and migration. Finally, nifedipine inhibited PDGF-induced Pyk2 activation in a dose-dependent manner.Conclusion: These data suggest that nifedipine interferes with VSMC migration via inhibition of the Pyk2-Src axis and inhibition of actin remodeling processes, including membrane ruffling and lamellipodium formation.

肉用種雄牛の能力検定の対象となる形質のように,測定が性によって限定され,世代が重複する選抜集団を想定した,モンテカルロシミュレイションによって,アニマルモデルによる育種価予測値に及ぼす形質記録および血統情報量の影響を検討した.集団は,雄5頭,雌100頭とし,初期遺伝率は0.3として,育種価予測値による選抜を7繁殖単位にわたり行なった.この選抜が加わったデータを用いて,基礎集団から順次,記録ならびに血統情報を削除し,育種価評価を行なった.その結果,3世代,少なくとも2世代に相当する記録ならびに血統情報を用いれば,育種価の真値と予測値の相関の低下や予測誤差分散の上昇を抑制できることが明らかになった.さらに,2ないし3世代さかのぼった情報による予測値による選抜シミュレイションを行なったところ,これらの結果と全情報を利用した選抜結果との間には大きな差異は生じなかった.

Computed tomography (CT) densities within coronary plaques measured by multislice CT have been shown to reflect plaque components. We evaluated an effect of statin therapies on characteristics of non-calcified coronary atherosclerotic lesions (NCALs) defined by CT density. We studied 92 consecutive stable patients (67 men, age 67 ± 9 years) with at least one NCAL detected by 64-slice CT angiography (CTA). We excluded patients with previous coronary revascularization procedures. Each NCAL (size >1-mm 2 , density 2 ). NCALs with 6-months before CTA in each patient. There were no significant differences in the patient’s characteristics and drug uses except for statin among the three groups classified by statin use (IS: n = 21, NS: n = 23, and no statin: n = 48). Serum LDL-cholesterol level (90 ± 18 vs. 115 ± 30 vs. 122 ± 34 mg/dl, p = 0.0005) and LDL/HDL-cholesterol ratio (1.6 ± 0.5 vs. 2.3 ± 0.7 vs. 2.5 ± 1.1, p = 0.002) were lower in the IS group than the others. A total of 191 NCALs (lipid-rich; 91 lesions) were detected by CTA. The number of all NCALs per patient was similar among the three groups (2.0 ± 0.9 vs. 2.1 ± 1.2 vs. 2.1 ± 1.0), while that of lipid-rich NCALs per patient was lower in the IS group than the others (0.5 ± 0.6 vs. 1.2 ± 0.9 vs. 1.1 ± 0.9, p = 0.01). On multivariate analysis regarding age, gender, coronary risk factors, and drug uses, the IS use was only significant predictor for decreasing lipid-rich NCALs (coefficient value −0.46, 95% CI −0.78– −0.14, p = 0.006). Otherwise, among the three groups classified by the number of lipid-rich NCALs per patient (absence: n = 26, one: n = 46, and ≥2: n = 20), the difference of LDL/HDL-cholesterol ratio was most significant (1.9 ± 0.6 vs. 2.1 ± 0.9 vs. 2.9 ± 1.1, p = 0.0004). Our CT findings support the concept that intensive statin therapy stabilizes lipid-rich coronary plaques. LDL/HDL-cholesterol ratio is most strongly related to lipid-rich NCALs on CTA.

Recent studies suggest that osteopontin (OPN) plays a critical role in the progression of atherosclerotic plaques and that angiotensin II (Ang II) is a potent upregulator of OPN expression. The goal of the present study was to characterize the signaling mechanisms whereby Ang II increases OPN expression in vascular smooth muscle cells (VSMC). YM-254890, a specific inhibitor of G(q/11), potently suppressed Ang II-induced OPN expression and ERK1/2 activation. Among dominant-negative (DN) mutants of small G proteins, only DN-Ras suppressed Ang II-induced OPN promoter activity. DN-MEK1 markedly inhibited Ang II-induced OPN promoter activity, while neither DN-JNK nor DN-p38 MAP kinase had any effect. DN-Src and DN-Fyn suppressed Ang II-induced OPN promoter activity. YM-254890 inhibited Ang II-induced Src and Ras activation, and PP2, a selective inhibitor for the Src kinase family, inhibited Ras activation, suggesting that the G(q/11)-Src-Ras axis is the upstream signaling cascade for Ang II-induced OPN expression. Finally, small interfering RNA against Ets-1 suppressed Ang II-induced OPN expression. In conclusion, these data suggest that Ang II-induced OPN expression in VSMC is mediated by signaling cascades involving G(q/11) the Ras-ERK axis, and the Src kinase family, and by the transcription factor, Ets-1. These signaling molecules may represent therapeutic targets for the prevention of pathological vascular remodeling.

Nasopharyngeal carcinoma (NPC) is a common public health problem in Thailand. Glutathione S-transferase M1 gene deletion (GSTM1 null genotype) carriers have been reported to be at increased risk and therefore this parameter is a potential marker for screening of NPC high-risk individuals. However, the conventional polymerase chain reaction (C-PCR) assay commonly used for GSTM1 null genotype detection is not suitable for mass screening since it is inconvenient, time consuming and unsafe due to the use of a toxic chemical. Currently, real-time PCR (R-PCR) assay is recommended for quicker and safer detection of various genetic polymorphisms. The aim of this study was to develop a SYBR green I R-PCR assay combined with melting curve analysis for GSTM1 polymorphism detection in Thai NPC patients. The results were compared to those from the C-PCR assay using DNA samples from peripheral blood leukocytes of 120 Thai NPC patients. The frequencies of GSTM1 polymorphism detected by the R-PCR and the C-PCR were the same. Forty-eight individuals that were GSTM1+ in the R-PCR assay showed 2 peaks with melting points of 82.5 and 87.5 that correlated with the appearance of 2 DNA bands in the C-PCR assay (i.e., one for GSTM1 at 215 base pairs (bp) and one for ?-globin at 268 bp). By contrast, 72 individuals that were GSTM1?- in the R-PCR assay showed 1 peak with a melting point of 87.5C that correlated with the appearance of 1 DNA band for -globin at 268 bp in the C-PCR assay. The R-PCR assay using SYBR Green I and melting curve analysis for GSTM1 polymorphism detection was as reliable as C-PCR assay but was quicker and safer and more amenable to large scale screening in Thai NPC cases.

This study was designed to determine whether Bach1 gene ablation leads to suppression of atherosclerosis in apolipoprotein E (Apo E)/Bach1 double knockout (DKO) mice. Apo E/Bach1 DKO mice were generated by intercrossing Apo E knockout (KO) and Bach1 KO mice. The animals were fed a high-fat diet for 8 weeks, and the atherosclerotic plaques in the thoracic and abdominal aorta were visualized by oil red O staining. In DKO mice, the total plaque area was reduced by 32% compared with that in Apo E KO mice. In DKO mice, heme oxygenase-1 (HO-1) was upregulated in the endothelium and, to a lesser extent, in vascular smooth muscles. In atherosclerotic plaques in Apo E KO mice and DKO mice, HO-1 was abundantly expressed in the endothelium and macrophages. Urine excretion of 8-iso-prostaglandin (PG) F2alpha, a marker for lipid peroxidation, was reduced in DKO mice compared with that in Apo E KO mice. The effects of Bach1 ablation on the plaque area and 8-iso-PG F2alpha excretion were almost completely abolished by treating DKO mice with Sn protoporphyrin, an inhibitor of HO activity. Disruption of the Bach1 gene in Apo E KO mice caused inhibition of atherosclerosis through upregulation of HO-1. Inhibition of Bach1, conversely, may be a novel therapeutic strategy to treat atherosclerotic diseases.

Background It has frequently been reported that Plasmodium vivax suppressed Plasmodium falciparum and ameliorated disease severity in patients infected with these two species simultaneously. The authors investigate the hypothesis that immunological responses stimulated by P. vivax may play a role in suppressing co-infecting P. falciparum. Methods Sera, taken sequentially from one of the authors (YN) during experimental infection with P. vivax, were added to in vitro cultures of P. falciparum. Cross-reactive antibodies against P. falciparum antigens, and cytokines were measured in the sera. Results Significant growth inhibitory effects upon P. falciparum cultures (maximally 68% inhibition as compared to pre-illness average) were observed in the sera collected during an acute episode. Such inhibitory effects showed a strong positive temporal correlation with cross-reactive antibodies, especially IgM against P. falciparum schizont extract and, to a lesser degree, IgM against Merozoite Surface Protein (MSP)-119. Interleukin (IL)-12 showed the highest temporal correlation with P. vivax parasitaemia and with body temperatures in the volunteer. Conclusion These results suggest the involvement by cross-reactive antibodies, especially IgM, in the interplay between plasmodial species. IL-12 may be one of direct mediators of fever induction by rupturing P. vivax schizonts, at least in some subjects. Future studies, preferably of epidemiological design, to reveal the association between cross-reactive IgM and cross-plasmodial interaction, are warranted.

Objective: To investigate whether the real-time polymerase chain reaction (R-PCR) assay with SYBR green I and melting curve analysis could be used for glutathione S-transferase M1 gene (GSTM1) polymorphism detection in Thai nasopharyngeal carcinoma (NPC) patients by comparing the results of this assay with the conventional PCR (C-PCR) assay. Methods: DNA samples from peripheral blood leukocytes of 60 Thai NPC patients were investigated in this study. GSTM1 polymorphism [GSTM1 normal genotype (GSTM1+) and GSTM1 null genotype (GSTM1-)] were examined by using the R-PCR assay with SYBR green I and melting curve analysis and the C-PCR assay. Results: The results of GSTM1 polymorphism detection by the R-PCR assay were in concordance with the C-PCR assay (κ= 1.0). Twenty-six individuals with GSTM1+ in the R-PCR assay showed 2 peaks of melting point at 82.5o C and 87.5o C that correlated with the appearance of 2 DNA bands of GSTM1 [215 base pair (bp)] and β-globin (268 bp) in the C-PCR assay, respectively. In addition, thirty-four individuals with GSTM1- in the R-PCR assay showed only 1 peak of melting point at 87.5o C that correlated with the appearance of 1 DNA band of β-globin (268 bp) in the C-PCR assay. Moreover, we found that the R-PCR assay was a faster and safer method for detection of GSTM1 polymorphism than the C-PCR assay. Conclusion: The present study suggests that the R-PCR assay with SYBR Green I and melting curve analysis may be a useful screening tool for more convenient, rapid, reliable, and safer detection of GSTM1 polymorphism in Thai NPC as compared to the C-PCR assay.

Background : Osteopontin (OPN), an extracellular matrix component produced by vascular smooth muscle cells (VSMC) and monocytes in response to biological stressors, is a regulator of cellular proliferation and migration. Recent studies revealed that OPN also plays a critical role in the progression of atherosclerotic plaques and that angiotensin II (AngII) is a potent upregulator of OPN expression. Therefore, the goal of the present study was to characterize the signaling mechanisms whereby AngII increases OPN expression. Methods and Results : YM254890, a specific inhibitor of G q/11 , potently suppressed AngII-induced OPN expression and ERK1/2 activation. Among DN mutants of small G proteins (Ras, Rac, Rho), only DN-Ras completely suppressed AngII-induced OPN promoter activity. Dominant negative (DN)-MEK1 inhibited AngII-induced OPN promoter activity by 54%, while DN-c-Jun N-terminal kinase (JNK) or DN-p38MAP kinase had no effect. DN-Src and Csk suppressed AngII-induced OPN promoter activity by 49% and 71%, respectively. In addition, small interfering RNA against Ets-1 (a transcriptional factor downstream of ERK1/2) suppressed AngII-induced OPN expression by 54 ± 4.3%. In a separate experiment, rats were treated with the AngII type I receptor blocker, valsartan (1 mg/kg/day), or vehicle for 2 weeks after carotid artery balloon injury. The intima/media ratio and OPN expression were significantly lower in valsartan-treated rats than in vehicle-treated rats. Conclusion : These data suggest that AngII-induced OPN expression in VSMC is mediated by signaling cascades involving G q/11 , the Ras-ERK axis, and c-Src, and by the transcription factor, Ets-1. Further, OPN may play a role in AngII-induced neointimal formation. These signaling molecules may represent therapeutic targets for the prevention of pathological vascular remodeling in patients with hypertension and atherosclerosis.

Background Nasopharyngeal carcinoma (NPC) is an Epstein-Barr virus (EBV)-associated malignancy that is common in Thailand. The association of the EBV nuclear antigen 2 gene ( EBNA2 ) and the latent membrane protein 1 gene ( LMP1 ) with NPC is unclear. Objective To determine the association between EBNA2 and LMP1 subtypes of EBV and NPC in Thais. Study design EBV DNA from blood samples of 75 Thai patients with NPC and 44 age-matched controls was examined by PCR for EBNA2 subtypes ( EBV type 1 and type 2 ) and LMP1 subtypes (wild-type LMP1 ( wt-LMP1 ) and LMP1 containing a 30-bp deletion ( del-LMP1 )). Results The frequencies of EBV type 1 in cases (96.0%) and controls (97.7%) were similar. The frequency of del-LMP1 in cases (58.7%) was higher than in controls (36.4%) ( p = 0.023). Among NPC patients, the frequency of del-LMP1 in stages III and IV (65.6%) was higher than in stages I and II (18.2%) ( p = 0.006). By analyzing nucleotide sequence of the LMP1 region, a new subtype, Thai1, was identified. Conclusion LMP1 subtypes of EBV may be involved in NPC susceptibility. The del-LMP1 variant may be a useful molecular marker for early detection, diagnosis and prognosis of Thai patients with NPC.

Background The level of circulating EBV DNA is a prognostic marker in patients with some EBV-associated malignant diseases. Objectives To investigate the presence and nature of Epstein-Barr virus (EBV) DNA in the plasma and to evaluate the correlation of plasma concentrations of EBV DNA with the EBV genomic status in peripheral blood T-cells and neoplastic cells and with the clinical outcome of patients with peripheral T-cell and NK-cell lymphomas (PTCL) and peripheral T-cell proliferative diseases (PTPD). Study design EBV DNA in the plasma of 45 patients and 45 controls was measured using real-time PCR. The presence of the EBV genome in the isolated peripheral blood lymphocytes (CD3 + and CD3 − cells) was analysed by PCR. Detection of EBV-encoded early RNA (EBER) in corresponding tumor tissues was carried out using in situ hybridization. DNase I digestion was applied to plasma samples to detect naked EBV DNA. Results Cell-free EBV DNA was detected in 32/38 (84%) of PTCL patients and 5/7 (71%) of PTPD patients, but not in the controls. Patients with EBV genome in peripheral blood CD3 + cells and EBV genome (EBER) in the tumor cells, compared to those without these findings, had significantly higher plasma EBV DNA levels. The majority of circulating EBV DNA molecules was naked form. The plasma EBV DNA levels were not related to survival. Conclusions The concentration of EBV DNA in the plasma was not a prognostic marker in PTCL and PTPD patients.

To estimate the species-specific mutation rates at the DRB1 locus in humans and chimpanzee, we analyzed the nucleotide sequence of a 37.6-kb chimpanzee chromosomal segment containing the entire Patr-DRB1*0701 allele and the flanking nongenic region and we compared it with two corresponding human sequences containing the HLA-DRB1*070101 allele using the sequence of HLA-DRB1*04011 as an outgroup. Because the allelic pair of HLA-DRB1*070101 and Patr-DRB1*0701 shows the lowest number of substitutions between the two species, it appears that these sequences diverged close to the time of the humans-chimpanzee divergence (6 million years ago). Alignment of the nucleotide sequences for HLA-DRB1*070101 and Patr-DRB1*0701 alleles showed that they share a high degree of similarity, suggesting that the stusdied chromosomal segments with these sequences have not been subjected to recombination since the humans-chimpanzee divergence. Comparison of the flanking 10.6 kb of nongenic sequences revealed an average of 41.5 and 83 single nucleotide substitutions in humans and chimpanzee, respectively. Thus, the species-specific nucleotide substitution rates in the flanking nongenic region were estimated to be 6.53 x 10 -10 and 1.31 x 10 -9 per site per year in humans and chimpanzee, respectively. Unexpectedly, the estimated rate in humans was twofold lower than in chimpanzee (P < 10 -3 , Tajima's relative rate test) and lower than the average substitution rate in the human genome. Because the nucleotide substitution rate in nongenic regions free from selection is expected to be equal to the mutation rate, the estimated substitution rate should correspond to the species-specific mutation rate at the DRB1 locus. Our results strongly suggest that the mutation rate at DRB1 locus differs among species.

Risk factors for cervical squamous intraepithelial lesions (SIL) including human papillomavirus (HPV) infection and the p53 codon 72 polymorphism were investigated in a case-control study with 103 cases and 105 controls in Northeastern Thailand. Increased risk for SIL was observed for age at menarche (odds ratio (OR) = 2.2; p0.005), age at the first sexual intercourse (OR=2.4; p0.05), number of sexual partners (OR=2.7; p0.005) and partners' smoking history (OR=2.3-3.2; p0.01). Prevalence of malignant type of HPV infection in the control and SIL groups was 18.1% and 60.2%, respectively. HPV infection significantly increased risk for SIL 6.8-fold (p0.001). HPV-16 infection was the commonest (31 out of 62 carriers) in SIL patients and highly associated with risk. The p53 codon 72 polymorphism was not identified as a genetic risk for SIL in this study, as demonstrated in Thai cervical cancer. Therefore, to prevent cervical neoplasia or HPV infection, inclusion of knowledge on sexual behavior and effects of smoking into public health programs is important and, at the same time, a nation-wide screening scheme for cervical abnormalities including HPV-typing is a high priority in Thailand.

Agouti signaling protein (ASIP) is an endogenous antagonist of melanocortin receptors that controls a wide range of physiological functions. Its central role in regulation of the melanocortin system implied that ASIP has been relevant to the evolution of various physiological traits in primates. In this study, we have tried to determine DNA sequences of the ASIP gene (ASIP) of various simian species to find molecular evolutionary aspects of ASIP. Unexpectedly, we found that the whole coding region of ASIP was missing only from the gibbon genome; gibbons constitute a large group of hominoid species in Southeast Asia. Our analyses revealed that unequal homologous recombination mediated by two AluSx elements erased a ∼100-kb region including ASIP from the gibbon genome. The data provide new evidence for the significant roles of Alu elements in the dynamic evolution of the primate genome.

Nasopharyngeal carcinoma (NPC) is a serious health problem in Thailand. It is caused by the combined effects of Epstein-Barr virus (EBV), carcinogens and genetic susceptibility. The glutathione S-transferase M1 gene (GSTM1) encodes a phase II enzyme responsible for detoxifying carcinogenic electrophiles. Polymorphic null forms of the gene GSTM1 lack enzyme activity and have been associated with susceptibility to several cancers including NPC. To examine the association between GSTM1 polymorphism and NPC susceptibility in Thais, GSTM1 genotypes (normal and null genotypes) in 78 NPC patients and 145 age-matched healthy controls were determined using PCR assays. Overall, no statistically significant differences were observed in the frequency of GSTM1 genotypes between cases and controls, nor among NPC patients compared on the basis of sex and clinical stage of disease. Carriers with the GSTM1 null genotype had a 2.9-fold increased risk for NPC of WHO type III when compared to those with GSTM1 normal genotype (P0.05 with OR =2.9, 95% CI = 1.2-6.8). When cases and controls were categorized into 3 age groups (40, (45 and (50 years), the frequencies of GSTM1 null genotype in cases the (45 and (50 age groups were significantly different from controls (P0.05). In addition, carriers of the GSTM1 null genotype in age groups (45 and (50 years had a 2-fold and 3-fold increased risk for NPC when compared to those with GSTM1 normal genotype (OR = 2.2, 95% CI = 1.1-4.7 and OR = 3.0, 95% CI = 1.2-7.5). We suggest that GSTM1 polymorphism may be associated with NPC susceptibility in Thais, especially for GSTM1 null genotype carriers of age higher than 45 years. The GSTM1 null genotype may be a useful genetic marker for predicting Thai NPC and for screening of early stages of Thai NPC.

Two missense polymorphisms (E272K and L374F) of the AIM1 locus, encoding a melanocyte differentiation antigen, were shown to have a clear association with human ethnicities. These two nonpathogenic single nucleotide polymorphisms (SNPs) may be associated with human pigmentation variation. In this study, we investigated sequence variation in the coding region and exon-flanking sequence and found low genetic variation only in subjects of European descent. All four statistical tests applied to the 7.55-kb region surrounding the L374F polymorphism detected statistically significant deviations from selective neutrality in Europeans. In addition, haplotype analysis revealed that one haplotype carrying 374F was overrepresented in this population, and the low rate of variation, with some features of selective sweeps, was shown to be statistically significant. These results suggest that positive selection recently has been acting or has acted on at least this region of the melanogenic gene and that an advantageous haplotype spread rapidly in Europe.

Background The latent membrane protein 1 (LMP1) of Epstein–Barr virus (EBV) has sequence heterogeneity. Some of the variants are associated with altered tumorigenic activity and show geographically specific localization. In Thailand, the EBV genome is frequently detected in circulating T cells of T-cell diseases. Objective To determine the role of EBV LMP1 variation in the genesis of T-cell diseases, we focused on virus factors and analyzed EBV strains in Thailand. Study design EBV DNA was extracted from 18 healthy individuals and 45 patients with T-cell diseases in Southern Thailand and 30 healthy individuals in Central Thailand. By using PCR-direct sequencing method, nucleotide sequences corresponding to the carboxyl terminus of the LMP1 were determined. Results Four known strains, B95-8 prototype, China 1, China 2 and Mediterranean (Med) and two novel strains, Southeast Asia 1 (SEA 1) and Southeast Asia 2 (SEA 2) were identified. The prevalence of China 2 strain was significantly different ( p = 0.006) between Central and Southern Thailand. Higher prevalence ( p = 0.026) of 30-bp deletion type in the Southern Thais was observed. The LMP1 Med strain was associated with the worse prognosis ( p = 0.029). Among T-cell diseases patients, CD3 + -cell oriented infection was recognized in SEA1 strain ( p = 0.025). Conclusion The distribution of EBV strains may be associated with geographic/ethnic and clinical background in the Thai population. Certain EBV strains defined by their LMP1 sequence may influence cell tropism, disease association, or disease severity.

Nitrosamine has been identified as a carcinogen for nasopharyngeal carcinoma (NPC). Here, we investigated if a nitrosamine metabolizing gene, cytochrome P450 2A6 (CYP2A6) played an important role in NPC development. Relationships between the disease and the CYP2A6 were studied in 74 NPC patients and 137 age-matched healthy controls by using PCR-RFLP assay to distinguish between a wide type allele, *1A, and two mutant alleles, *1B and *4C. Overall, a significant association between CYP2A6 polymorphism and NPC development was observed (P

It has been suggested that SDF1-G801A, a single nucleotide polymorphism (SNP) in the 3' untranslated region (UTR) of the SDF1 gene, is associated with susceptibility to diseases such as AIDS and type-I diabetes. However, experimental studies examining the effect of SDF1-G801A on SDF-1 expression have not supported its functional importance. In this study, to examine whether other polymorphisms have a cis-acting effect on SDF1 expression, we carried out haplotype analyses of the SDF1 gene and the allele-specific transcript quantification utilizing Epstein-Barr virus-transformed lymphoblastoid cell lines with heterozygous genotype for SDF1-G801A. Haplotype-based analyses on the proportion of the allele-specific transcripts revealed the presence of haplotypes associated with a decreased amount of the transcripts. In addition, we observed haplotypic variation in response to dibutyl cyclic AMP and tetradecanoyl phorbol acetate that enhances the levels of SDF-1 transcripts probably through activation of transcription factors. Showing evidence that polymorphisms other than the SDF1-G801A have a cis-acting effect on expression of SDF-1 transcripts, the results of this study contribute to the interpretation of previous disease-association studies and to the selection of SNP markers for future studies. As shown in this study, allele-specific transcript quantification coupled with haplotype analyses can be an effective tool for detecting cis-acting polymorphisms in expressional regulation.

A case of spontaneous malignant lymphoma in a Japanese macaque (Macaca fuscata) was pathologically, etiologically and virologically studied. Nasal cavity was involved in the neoplastic lesions in addition to lymphoid and visceral tissues. Histopathological analyses revealed the presence of neoplastic cells classified into histiocytic Hodgkin-like cells and Reed-Sternberg-like cells. Histiocytic Hodgkin-like cells were CD16+ and CD20+, and the CD16+ cells were also positive for simian Epstein-Barr virus (sEBV)-encoded early RNA transcripts. RS-like cells were negative for CD3, CD16 and CD20. Antibodies to early antigen of sEBV were detected, while antibodies to simian T-cell leukemia virus-1 were negative. The case may correspond to EBV-associated nasal type NK/T-cell lymphoma in humans rather than Hodgkin lymphoma.

Contemporary hunter–gatherer groups are often thought to serve as models of an ancient lifestyle that was typical of human populations prior to the development of agriculture. Patterns of genetic variation in hunter–gatherer groups such as the !Kung and African Pygmies are consistent with this view, as they exhibit low genetic diversity coupled with high frequencies of divergent mtDNA types not found in surrounding agricultural groups, suggesting long-term isolation and small population sizes. We report here genetic evidence concerning the origins of the Mlabri, an enigmatic hunter–gatherer group from northern Thailand. The Mlabri have no mtDNA diversity, and the genetic diversity at Y-chromosome and autosomal loci are also extraordinarily reduced in the Mlabri. Genetic, linguistic, and cultural data all suggest that the Mlabri were recently founded, 500–800 y ago, from a very small number of individuals. Moreover, the Mlabri appear to have originated from an agricultural group and then adopted a hunting–gathering subsistence mode. This example of cultural reversion from agriculture to a hunting–gathering lifestyle indicates that contemporary hunter–gatherer groups do not necessarily reflect a pre-agricultural lifestyle., Genes, language and culture reveal that the Mlabri reverted from an agricultural to a hunter-gatherer lifestyle, suggesting that hunter-gatherer groups might not always represent the pre- agricultural lifestyle of humans

Toxoplasma gondii infection was studied in Khon Kaen, northeastern Thailand. Blood specimens were collected from 493 non-pregnant women between 2009 and 2012. Presence of antibodies to T. gondii was determined using the latex agglutination test (cutoff titer 1:32). Thirteen of 493 (2.6%) were found to be seropositive for T. gondii infection. There was no age dependence in the prevalence. The present study reporting a low prevalence of T. gondii infection in northeastern Thailand suggests that the traditional lifestyles and climatic environments may limit the emergence of toxoplasmosis in this region.

HPV infection is the main cause of cervical cancer; however, factors that promote and maintain HPV infection are still unclear. This study was designed to search for factors responsible for the HPV infection in Northeastern Thai women. A total of 190 volunteers with a normal histopathologic appearance of cervix as controls (n=100) and with squamous cell cervical carcinoma (SCCA) (n=90) were the subjects. Variables of risk factors including sexual behaviors, history of reproduction, history of sexually transmitted diseases and smoking were conducted with self-report and direct interview. Number of sexual partners and smoking history increased the likelihood of high-risk HPV infection. Multiple sexual partners showed significantly higher 3.94-fold risk for HPV infection (95% CI = 1.82-8.82, p-value0.001). Smoking history of partner increased the risk for HPV infection 3.03-fold (95%CI=1.42-6.58, p-value0.002). After OR were adjusted, significant difference was still observed in the number of sexual partners (p-value0.0001) and smoking history of the partner (p-value0.005). To decrease the incidence of cervical cancer, we should prevent HPV dissemination and be on the alert for having multiple sexual partners and a partner's smoking habit, which must be included in our public health planning.

Specific subtypes of malignant lymphoma are highly associated with Epstein-Barr virus (EBV) infection. In the present study, the authors evaluated EBV-encoded RNA (EBER) expression by in situ hybridization in 300 cases of malignant lymphomas diagnosed by lymph node biopsy, with 100 cases of reactive lymphoid hyperplasia in lymph nodes as controls, for comparison. There were 100 consecutive cases of classical Hodgkin's lymphoma (cHL), 100 consecutive cases of non-Hodgkin's lymphoma, B cell (NHL-B), and 100 consecutive cases of non-Hodgkin's lymphoma, T cell (NHL-T). EBER expression was detected in 46% of reactive lymphoid hyperplasia cases, but the positively stained cells in those cases constituted less than 5 percent of the total cell populations. When using the presence of EBER in 5 percent or more of the cell population and/or the presence of EBER in the Hodgkin's Reed-Sternberg's cells as indicators of positivity, 64% of cHL, 13% of NHL-B, and 51% of NHL-T were found to be positive. The study indicates a strong association of cHL and NHL-T with EBV infection, the link apparently being weaker for NHL-B except for the subtypes of Burkitt's lymphoma and diffuse large B cell lymphoma.

Leber's hereditary optic neuropathy (LHON) is a maternally inherited disease caused by mitochondrial DNA (mtDNA) mutations. In this study, the mtDNA/nuclear DNA ratio was evaluated in 11 LHON patients with the 14484 mutation, 13 asymptomatic carriers and 18 non-carrier relatives as controls, to reveal possible relationships between the disease and mtDNA content. DNAs from peripheral blood lymphocytes were subjected to quantitative PCR. Gender differences and age-dependent changes in the mtDNA content were not observed. Significant increase in the mtDNA content was observed only in the asymptomatic carriers (P

Relationships between cervical cancer and risk factors were investigated in Northeastern Thailand. Cases (n = 90) with squamous cell cervical cancer (SCCA) and age matched healthy controls (n = 100) were recruited. The p53 codon 72 polymorphism, proline and arginine allele, was studied by the polymerase chain reaction-restriction fragment length polymorphism. There was no significant difference in the allele and the genotype distribution between the SCCA and the control groups (P > 0.05). Significant difference was observed in the number of sexual partners (P < 0.003) age at the first sexual intercourse (P < 0.03) and number of parities ( P< 0.006). After adjusted by age and p53 genotype, significant difference was still observed in the number of sexual partners (P = 0.017) The partners' smoking increased the risk to develop SCCA. Increased odds ratios were observed when the partner had smoking history both at present (3.31; P < 0.003) and in the past (3.36; P < 0.003). The p53 polymorphism itself may not be a risk factor for cervical cancer in Northeastern Thailand. Much attention should be paid to the presence of other risk factors such as sexual behaviors and smoking habits in the prevention of cervical cancer in this region.

Abnormal Ca2+ handling and enhanced aggregation response have been reported in platelets from spontaneously hypertensive rats (SHR) and patients with essential hypertension, and thought to be involved in the progression of target organ damage of hypertension. It is important to examine whether antihypertensive therapy can improve the abnormal platelet response in hypertension. We investigated the effect of antihypertensive treatment such as amlodipine and cilazapril on Ca2+ handling and aggregation response in SHR platelets. Four-week-old male SHR were divided into three groups. Each group was treated with amiodipine (A: 10 mg/kg/day), cilazapril (C: 10 mg/kg/day) or vehicle (V) for 8 weeks by gavage. At 12-week-old, platelet [Ca2+]i was measured with fura-2 in each group of SHR and age-matched Wistar-Kyoto rats (WKY) as normal control. Systolic blood pressure in amlodipine and cilazapril treated groups were similar with WKY and significantly lower than vehicle treated group (A: 124 +/- 9, C: 126 +/- 9, WKY: 122 +/- 10 and V: 180 +/- 9 mmHg, respectively). The basal [Ca2+]i in the three groups of SHR were similar and higher than WKY (A: 47 +/- 1.7, C: 47 +/- 1.2, V: 48 +/- 3.9 and WKY: 40 +/- 4.0 nmol/l, respectively). There were no significant differences in thrombin (0.1 U/ml)-stimulated [Ca2+]i rise in the presence or absence of extracellular Ca2+ among the three groups of SHR and these were higher than WKY. Intracellular Ca2+ discharge capacity, assessed by the ionomycinstimulation was similar in the all groups. Thrombin-induced maximum platelet aggregation responses in the three groups of SHR were similar and higher than WKY. The antihypertensive treatment of Ca2+ antagonist or ACE inhibitor gave no change in intraplatelet Ca2+ metabolism in SHR. These results support the hypothesis that an abnormal Ca2+ handling in SHR platelet is genetically determined and not improved by hypotensive therapy.

Peripheral T-cell lymphoma (PTCL) is a group of diseases which are common in Asia and areas of South and Central America. They are highly associated with the Epstein-Barr virus (EBV) infection. In the present study the authors evaluated patients with gastrointestinal involvement of PTCL with respect to clinical findings and outcome, pathologic features, and molecular analysis for EBV infection and the clonality of tumor cells. From January 1997 through December 2000, 7 patients with gastrointestinal tract involvement of PTCL were identified. The frequency of gastrointestinal tract involvement in the various types of PTCL was 5.4 per cent (7 of 129 cases). The pertinent clinical features were prolonged fever, weight loss, anemia, hepatosplenomegaly, lymphadenopathy, multiorgan involvement, and gastrointestinal bleeding. Laboratory results showed a significantly high serum level of alkaline phosphatase and lactate dehydrogenase, and abnormal coagulograms. Five patients died within 4 months after onset of illness, while two were in complete remission after chemotherapy. The tumor cell morphology was classified into three categories: small-sized cells, mixed medium- and large-sized cells, and large-sized cells. The antigenic phenotypes of the tumor cells were LCA+, CD3+, CD15-, CD16-, CD30-, CD45R0+, CD57-, CD68-, EMA-, betaF1-, granzyme B+, TIA-1+, and p53+. The expression of CD4, CD8, CD56 and CD20 was variable. EBV-RNA expression by in situ hybridization (EBER-ISH) study was positive and T-cell receptor (TCR) beta and/or gamma gene rearrangements were detected in all patients. DNA sequence analysis showed high identity to the human TCR germline gene. PTCL with gastrointestinal tract involvement was associated with EBV infection. The tumor cells were mature T cells with some NK-cell antigenic expression and all demonstrated TCR gene rearrangements.

Recently it has been shown that the gene-density correlated radial distribution of human 18 and 19 homologous chromosome territories (CTs) is conserved in higher primates in spite of chromosomal rearrangements that occurred during evolution. However, these observations were limited to apes and New World monkey species. In order to provide further evidence for the evolutionary conservation of gene-density-correlated CT arrangements, we extended our previous study to Old World monkeys. They comprise the remaining species group to be analyzed in order to obtain a comprehensive overview of the nuclear topology of human 18 and 19 homologous CTs in higher primates. In the present study we investigated four lymphoblastoid cell lines from three species of Old World monkeys by three-dimensional fluorescence in situ hybridization (3D-FISH): two individuals of Japanese macaque (Macaca fuscata), crab-eating macaque (Macaca fascicularis), and an interspecies hybrid individual between African green monkey (Cercopithecus aethiops) and Patas monkey (Erythrocebus patas). Our data demonstrate that gene-poor human 18 homologous CTs are located preferentially close to the nuclear periphery, whereas gene-dense human 19 homologous CTs are oriented towards the nuclear center in all cell lines analyzed. The gene-density-correlated positioning of human 18 and 19 homologous CTs is evolutionarily conserved throughout all major higher primate lineages, despite chromosomal inversions, fusions, fissions or reciprocal translocations that occurred in the course of evolution in these species. This remarkable preservation of a gene-density-correlated chromatin arrangement gives further support for a functionally relevant higher-order chromatin architecture.

The codon 72 polymorphism of the p53 tumor suppressor gene has been investigated extensively for its association with various cancers around the world. However, its influence has not been elucidated in the Thai population. Therefore, a case-control study with 97 patients and 97 matched controls was conducted to elucidate the association between the polymorphic p53 and oral cancer risk in a Southern Thai population. The frequencies of the Arg/Arg, Arg/Pro, and Pro/Pro genotypes were 36%, 35%, and 29%, respectively in the controls and 33%, 45% and 22%, respectively in the patients. This study shows that there was no significant association between the p53 codon 72 polymorphism and oral cancer risk. There was also no link with respect to smoking or drinking habits. However, our data suggest that for individuals who were younger than 65 years old, the Pro/Pro genotype may offer some protection against oral cancer (OR = 0.13, 95%CI 0.04-1.10). This is the first report on p53 polymorphism and oral cancer in Thailand.

Several lines of evidence suggest that patterns of genetic variability in the human angiotensinogen gene (AGT) contribute to phenotypic variability in human hypertension. The A(−6) promoter variant of AGT is associated with higher plasma angiotensinogen levels and increased risk of essential hypertension. The geographic distribution of the A(−6) variant leads to the intriguing hypothesis that the G(−6) promoter variant has been selectively advantageous outside Africa. To test these hypotheses, we investigated the roles of population history and natural selection in shaping patterns of genetic diversity in AGT, by sequencing the entire AGT gene (14,400 bp) in 736 chromosomes from Africa, Asia, and Europe. We found that the A(−6) variant is present at higher frequency in African populations than in non-African populations. Neutrality tests found no evidence of a departure from selective neutrality, when whole AGT sequences were compared. However, tests restricted to sites in the vicinity of the A(−6)G polymorphism found evidence of a selective sweep. Sliding-window analyses showed that evidence of the sweep is restricted to sites in tight linkage disequilibrium (LD) with the A(−6)G polymorphism. Further, haplotypes carrying the G(−6) variant showed elevated levels of LD, suggesting that they have risen recently to high frequency. Departures from neutral expectation in some but not all regions of AGT indicate that patterns of diversity in the gene cannot be accounted for solely by population history, which would affect all regions equally. Taken together, patterns of genetic diversity in AGT suggest that natural selection has generally favored the G(−6) variant over the A(−6) variant in non-African populations. However, important localized effects may also be present.

Nasopharyngeal carcinoma (NPC) is a serious cancer in Thailand. To address on the genetic risk factor for NPC, we investigated association between the p53 codon 72 polymorphism (Pro/Arg) and NPC susceptibility in the Thai. The genotype frequency of this polymorphism in 102 NPC patients and 148 age-matched healthy controls was determined by using a PCR-RFLP assay. No statistically significant difference in the overall genotype frequencies or allele frequencies between cases and controls was observed. Among NPC patients, no statistical significant difference in p53 genotype frequencies between sex, histological types and clinical stages was observed. When cases and controls were categorized into 3 groups of age,40,45 and50 years, the frequencies of p53 genotype in the cases were significantly different from those of the controls (P0.05). The p53 Pro homozygotes with age of40 years had twofold to threefold higher risk to develop NPC and the risk was increased with age (Odds Ratio (OR) increased from 2.01 to 2.63 by age40 to50 years). Individuals of age40,45 and50 years with an Arg/Arg genotype and of age45 and50 years with combined Arg/Arg or Arg/Pro genotype had lower risk to develop NPC than those with Pro/Pro genotype (P0.05). Collectively, we suggest that the p53 gene polymorphism may associate with NPC susceptibility in Thai population, particularly the Pro/Pro genotype carriers with age of40 years. The detection of this p53 polymorphism may be a useful tool for screening of early stage and diagnosis of NPC.

Epstein-Barr virus (EBV) is an important causal factor of human nasopharyngeal carcinoma (NPC). High levels of serum IgA and IgG antibodies to EBV early and viral capsid antigens (IgA/EA, IgA/VCA, IgG/EA and IgG/VCA) have been reported in NPC patients. Since specific serum IgA/EA, IgA/VCA and IgG/EA are claimed to be useful serological markers for NPC. In order to evaluate whether plasma IgA/EA, IgA/VCA, IgG/EA and IgG/VCA antibody levels are useful markers for diagnosis and prognosis of Thai NPC, we examined the prevalence of these antibodies in 79 NPC patients, and 127 age-matched controls (47 healthy subjects (HS), 32 cases of other disease (OD) and 48 cases of other cancer (OC)) by using an indirect immunofluorescence assay. The prevalence of plasma IgA/EA, IgA/VCA, and IgG/EA in NPC patients (55.7, 68.4 and 68.4%) was significantly higher than in the HS (0.0, 0.0 and 20.5%,), OD (0.0, 0.0 and 3.1%) and OC (0.0, 0.0 and 20.8%) groups (p0.05). The prevalence of plasma IgG/VCA in NPC patients (93.7%) was significantly different from those for the OD and OC groups (71.9 and 43.8%) but not for the HS group (89.4%). In NPC patients, the geometric mean titers (GMT) of plasma IgA/EA, IgA/VCA and IgG/EA were increased with an advanced clinical stage of disease but not IgG/VCA. In contrast, GMT of IgG/VCA was increased with aggressive type of disease (histological type) but not IgA/EA, IgA/VCA, and IgG/VCA. The results of our study suggest that plasma IgA/EA, IgA/VCA and IgG/EA antibodies may be useful markers for diagnosis and assessing prognosis of Thai NPC.

The effects of the SDF1-3'A on AIDS progression have been attributed to the altered amount of stromal cell-derived factor 1 (SDF-1). However, the contribution of the SDF1-G801A polymorphism to SDF-1 expression is still unclear. In contrast to fresh peripheral blood mononuclear cells (PBMCs), Epstein-Barr virus (EBV)-transformed lymphoblastoid cell lines (LCLs) express the SDF-1 mRNA. Using EBV-transformed LCLs from 42 individuals with different genotypes, we investigated the SDF-1 mRNA levels and methylation status in the SDF1 gene. Both in PBMCs and in EBV-transformed LCLs, CpG dinucleotides in the 5' region of the SDF1 gene were unmethylated. As for the 3' untranslated region (3'UTR), by contrast, CpG dinucleotides were methylated in PBMCs, whereas site-specific demethylation around the polymorphic site was detected in EBV-transformed LCLs. The levels of the demethylation were correlated with the SDF-1 mRNA levels. However, the genotype for the SDF1-G801A polymorphism did not significantly alter the SDF-1 mRNA levels. The allele preferences in transcription and methylation were also absent in the heterozygous cells. In conclusion, this study suggested a contribution of site-specific demethylation in the 3'UTR to the SDF1 gene expression, but did not show any evidence for the contribution of the SDF1-G801A polymorphism to the amount of the SDF-1 mRNA.

Leber's hereditary optic neuropathy (LHON) is a maternally inherited late-onset form of blindness characterized by acute or subacute bilateral retinal degradation resulting in a permanent loss of central vision. G11778A, C3460A, and T14484C mutations on mitochondrial DNA (mtDNA) are specific for LHON and account for most, but not all, worldwide LHON cases. A six-generation Indonesian LHON family with the T14484C mutation was analyzed. Polymerase chain reaction/restriction fragment length polymorphism analysis showed that all of the maternal lineages had the T14484C mutation in a homoplasmic form. Penetrance of the disease (33.3%) and male predominance (3:1) was similar to other worldwide LHON with the T14484C mutation. The incidence of offspring born to affected mothers was no different from that of unaffected mothers, and the age distribution of cases was no higher than that of asymptomatic carriers. Eight secondary mutations were sought but not detected. The patients of this family belonged to haplogroup M. These findings support the idea that the mtDNA backgrounds involved in the expression of LHON mutations in southeast Asians are different from those of Europeans.

We have attempted to find out any relationships between circulating tumor necrosis factor (TNF)-alpha levels and Epstein-Barr virus (EBV) associated peripheral T-cell and NK-cell proliferative disease/lymphoma (PTPD/L) status. The distribution of TNF-alpha level was significantly higher (P0.05) in patients than in controls. Patients carrying EBV genome in their peripheral T-cells showed higher TNF-alpha levels than the patients with EBV negative peripheral T-cells (P0.001). Among patients whose peripheral T-cells were positive for EBV genome, TNF-alpha levels between the wild type LMP-1 gene carriers and the 30-bp deletion type LMP-1 gene carriers were compared and the wild type LMP-1 gene carrier group showed significantly higher TNF-alpha levels (P0.01). As for the outcome of the patients and TNF-alpha levels, significant differences were observed between dead and alive with disease group (P0.001), and dead and alive with complete remission group (P0.01). Since circulating TNF-alpha levels in PTPD/L patients correlate with the disease and EBV infection status, it may be possible that monitoring of the TNF-alpha levels will be a useful prognostic marker.

Mitochondrial DNA (mtDNA) polymorphisms in the D-loop region and the intergenic COII/tRNA(Lys) 9-bp deletion were examined in 180 individuals from all nine aboriginal Taiwanese groups: Atayal, Saisiat, Bunun, Tsou, Rukai, Paiwan, Ami, Puyuma, and Yami. A comparison of 563-bp sequences showed that there were 61 different sequence types, of which 42 types were specific to respective aboriginal groups. D-loop sequence variation and phylogenetic analysis enabled the 180 aboriginal lineages to be classified into eight monophyletic clusters (designated C1-C8). Phylogeographic analysis revealed that two (C2 and C4) of the eight clusters were new characteristic clusters of aboriginal Taiwanese and accounted for 8.3% and 13.9% of the aboriginal lineages, respectively. From the estimated coalescent times for the two unique clusters, the mtDNA lineages leading to such clusters were inferred to have been introduced into Taiwan approximately 11,000-26,000 years ago, suggesting ancient immigrations of the two mtDNA lineages. Genetic distances, based on net nucleotide diversities between populations, revealed three distinct clusters that were comprised of northern mountain (Atayal and Saisiat), southern mountain (Rukai and Paiwan), and middle mountain/east coast (Bunun, Tsou, Ami, Puyuma, and Yami) groups, respectively. Furthermore, phylogenetic analysis of 16 human populations (including six other Asian populations and one African population) confirmed that the three clusters for aboriginal Taiwanese had remained largely intact. Each of the clusters (north, south, and middle-east coast) was characterized by a high frequency of a particular lineage (C4, C2, and 9-bp deletion, respectively). This may result from random genetic drift among the aboriginal groups after a single introduction of all the mtDNA lineages into Taiwan, but another plausible explanation is that at least three genetically distinct ancestral populations have contributed to the maternal gene pool of aboriginal Taiwanese.

Parallel studies of (a) patients with Epstein-Barr virus (EBV)-associated peripheral T-cell proliferative disease/lymphomas and (b) a group of patients with a prolonged fever from other causes were conducted at Songklanagarind University Hospital from 1997 through 2000. (Reports on EBV-associated peripheral T-cell and NK-cell proliferative disease/lymphomas have been published elsewhere) In this study, the authors identified 58 patients; 14 were non-Hodgkin's lymphoma of B-cell origin (NHL-B), 8 were Hodgkin's disease, 6 were acute leukemia, 9 were systemic lupus erythematosus (SLE), and 21 were patients with other diseases. Serologic tests for the EBV infection, the study of EBV genome in circulating non-T-cells (CD3-cells) and T-cells (CD3+ cells), and the EBV-RNA study in the tumor cells were performed. EBV internal repeat-1 region (IR-1) in peripheral blood CD3+ cells was detected in 10 of 14 patients (71.5%) with NHL-B, 3 of 8 patients (37.5%) with Hodgkin's disease, 1 of 6 patients (16.7%) with acute leukemia, 4 of 9 patients (44.5%) with SLE, and was not detected in any of the 21 patients with other diseases. Anti-viral capsid antigen-IgG was significantly elevated in hematologic malignancy patients with EBV IR-1 genome in the peripheral blood CD3+ cells when compared to hematologic malignancy patients with a negative result, whereas there was no significant difference in anti-EBV nuclear antigen among these two groups. EBV-RNA expression in tumor cells by in situ hybridization was detected in 4 of 13 patients (31%) with NHL-B (all showed EBV IR-1 genome in peripheral blood CD3+ cells), and 3 of 5 patients (60%) with Hodgkin's disease (only two showed EBV IR-1 genome in peripheral blood CD3+ cells). These data support the theory that chronic EBV infection is often found in association with cases of NHL-B, Hodgkin's disease, acute leukemia, and SLE.

To evaluate the resistance of SAO against species specific malaria infection, relationships between parasite species and the 27-bp deletion in the band 3 gene were studied in malaria endemic Sumba Island, eastern Indonesia. Thick blood films were prepared from patients with malaria symptoms (n=129) and healthy controls (n=231). Species of Plasmodium was identified by microscopic observation. The 27-bp deletion was screened by the PCR method. Among 231 healthy controls, 29 (12.6%) had the 27-bp deletion, whereas 14 (10.9%) among 129 patients confirmed with malaria infection harbored the 27-bp deletion. No significant difference was observed in the prevalence of the 27-bp deletion between controls and patients (p0.8). There was no significant difference in the frequency of the 27-bp deletion between P. vivax and P. falciparum infected subjects at 5% level by Fisher's exact test. The present result showing no correlation between the presence of the 27-bp deletion and infected parasite species is consistent with the post-invasion resistance hypothesis that may involve not a single malaria species.

Overlapping of genes, especially in an anti-parallel fashion, is quite rare in eukaryotic genomes. We have found a rare instance of exon overlapping involving CHRNE and MINK gene loci on chromosome 17 in humans. CHRNE codes for the epsilon subunit of the nicotinic acetylcholine receptor (AChRepsilon) whereas MINK encodes a serine/threonine kinase belonging to the GCK family. To elucidate the evolutionary trail of this gene overlapping event, we examined the genomes of a number of primates and found that mutations in the polyadenylation signal of the CHRNE gene in early hominoids led to the overlap. Upon extending this analysis to genomes of other orders of placental mammals, we observed that the overlapping occurred at least three times independently during the course of mammalian evolution. Because CHRNE and MINK are differentially expressed, the potentially hazardous mutations responsible for the exon overlap seem to have escaped evolutionary pressures by differential temporo-spatial expression of the two genes.

The entire nucleotide sequences of 70 hepatitis B virus (HBV) isolates of genotype B (HBV/B), including 38 newly determined and 32 retrieved from the international DNA database (DDBJ/EMBL/GenBank), were compared phylogenetically. Two subgroups of HBV/B were identified based on sequence divergence in the precore region plus the core gene, one with the recombination with genotype C and the other without it. The analysis over the entire genome of HBV/B by the SimPlot program located the recombination with genotype C in the precore region plus the core gene spanning nucleotide positions from 1740 to 1838 to 2443 to 2485. Within this genomic area, HBV/B strains with the recombination had higher nucleotide and amino acid homology to genotype C than those without the recombination (96.9 versus 91.1% in nucleotides and 97.0 versus 92.9% in amino acids). There were 29 HBV/B strains without the recombination, and they were all recovered from carriers in Japan. The remaining 41 HBV/B isolates having the recombination with genotype C were from carriers in China (12 strains), Hong Kong (3 strains), Indonesia (4 strains), Japan (3 strains), Taiwan (4 strains), Thailand (3 strains), and Vietnam (12 strains). Due to the frequency of the distribution of HBV/B without the recombination (29 of 32 isolates, or 91%) and the fact that it was exclusive to Japan, it was provisionally classified into the Bj (j standing for Japan) subgroup, and HBV/B with the recombination was classified into the Ba (a for Asia) subgroup. Virological differences between HBV/Bj and HBV/Ba may be reflected in the severity of clinical disease in the patients infected with HBV of genotype B, which seems to be under strong geographic influences in Asia., published_or_final_version