In vitro vessel-forming capacity of endothelial progenitor cells in high glucose conditions

In type 2 diabetes, the impairment of vascular repair processes and angiogenesis are due to endothelial progenitor cell (EPC) dysfunction. In this study, we established a quantitative methodology to assess EPC function by using an in vitro 5-(6)-carboxyfluorescein diacetate succinimidyl ester-labeling vessel formation assay. The EPCs were cultured in three different glucose concentrations (100, 189.5, and 295.5 mg/dl of d-glucose) representing normal control and diabetes with either good or poor glycemic control, respectively. We found that the in vitro vessel-forming capacity was impaired in EPCs cultured in high glucose concentrations compared to normal control (43.4 ± 0.8% and 34.7 ± 0.7% vs. 50.8 ± 2.1%). We further studied expression of various genes involved in vessel formation. There was a lower level of angiopoietin 1 gene expression in EPCs cultured in high glucose concentrations. The addition of recombinant angiopoietin 1 significantly increased the vessel-forming capacity of EPCs cultured in high glucose concentration (35.3 ± 2.0% to 48.8 ± 2.7%), whereas the addition of angiopoietin 2 (a competitive inhibitor of angiopoietin 1) impaired the vessel-forming capacity of EPCs cultured in normal glucose concentration (51.8 ± 1.3% to 41.3 ± 0.6%). We conclude that the in vitro vessel-forming capacity of EPCs cultured in high glucose concentration is impaired due to low levels of angiopoietin 1.     

School-based helminthiases control: I. A baseline study of soil-transmitted helminthiases in Nakhon Si Thammarat Province,Thailand

A baseline study of soil-transmitted helminthiases was carried out in Nakhon Si Thammarat Province, southern Thailand. The study sites were Wat Krou Chou Primary School and nearby villages in Sichon district, and Wat Thang Phoon Primary School and nearby villages in Chalerm Phrakiat District. Surveys of the schoolchildren's stools were conducted by the Kato-Katz technique. The results showed that 23.7% of schoolchildren in Wat Krou Chou and 24.7% of those in Wat Thang Phoon were infected with soil-transmitted helminths, with a 24.1% overall infection rate. The major infection was hookworm (22.2% and 19.6%) and the minor one was trichuriasis, (2.9% and 8.7% respectively). The intensity of infection was similar in both schools, 85.7% and 90.2% respectively for light intensity hookworm. Schoolchildren with hookworm infection were not anemic. The hemoglobin value of children with hookworm infection was not significantly different from that of uninfected children. Data regarding the health behavior of children's parents in both schools were reported.     

Immunophenotypic profile of adult acute myeloid leukemia (AML): analysis of 267 cases in Thailand

Little data exists in Thailand and other Southeast Asian countries regarding the biological characteristics of adult acute myeloid leukemia (AML). In this study, we performed a flow cytometric analysis of 267 Thai adult AML cases to delineate the pattern of leukemic cell surface antigens. Forty-eight cases (18%) were identified as acute promyelocytic leukemia (M3) and 219 cases as non-M3. The most frequent subtype of AML in Thailand was M1/M2 and the least frequent was M7. M3 immunophenotypes were characterized by their unique lack of expression of CD34 and HLA-DR as contrast to the high mean expression of 50% and 70%, respectively, in non-M3. Overall, 60% of cases expressed CD34. Aberrant lymphoid antigens were uniquely seen in specific subtypes of Thai AML, including CD19 (33% of non-M3 vs 23% of M3) and CD2 (12% of M3 vs 2% of non-M3). CD56 was frequently expressed in both M3 and non-M3 while CD16 appeared to be associated with M4/M5 (24% of cases) and CD7 with M1/M2 (21% of cases). Eighty-one percent of non-M3 expressed CD38 while only 53% of M3 did. We found that most Thai adult AML patients were on average 15-20 years younger than those of the West or Japan with only 25% of Thai cases over 60 years of age, although the immunophenotypes were not markedly different. Biological studies of acute leukemia in various countries should help to provide epidemiological clues that play a role in the pathogenesis of leukemia in different geographic regions of the world. Our study represents the largest series of AML ever investigated in the Southeast Asian region.     

Preliminary clinical evaluation of a protein chip for tumor marker serodiagnosis of various cancers

This preliminary study aimed to investigate sensitivity and specificity of a protein chip system for multi-tumor marker serodiagnosis of ten types of cancers, and to understand the possible clinical applications of this protein chip for the Thai population. The specific cancers diagnosed by this protein chip are lung, breast, liver, cervix, colo-rectal, stomach, ovary, esophagus, prostate and pancreas cancers. We analyzed 215 serum samples of which 165 were obtained from clinically confirmed cancer patients and 50 from healthy people with no evidence of cancer. The sensitivity and specificity of the protein chip were 82.4% and 94.0%, respectively. The success rate of the protein chip for detecting all 10 types of cancers varied from 57% to 100%. The value of the simultaneous measurement of multiple tumor markers using the protein chip for cancer screening lied in the higher sensitivity compared to using single tumor markers for each type of cancer. In short, protein chips may be useful in mass screening for cancer during health checkups as well as for metastasis follow-up of cancer patients.     

Risk factors for leukemia in Thailand

A case-control study of adult-onset leukemia was conducted in Bangkok, Thailand to explore the contribution of cellular telephone use and other factors to the etiology of the disease; 180 cases (87 acute myeloblastic leukemia, 40 acute lymphoblastic leukemia, 44 chronic myelogenous leukemia, eight chronic lymphocytic leukemia, one unclassified acute leukemia) were compared with 756 age- and sex-matched hospital controls. Data were obtained by interview; odds ratios (ORs) were estimated by unconditional logistic regression. There was no clear association with cellular telephone phone use, but durations were relatively short (median 24–26 months), and there was a suggestion that risk may be increased for those with certain usage practices (ORs, 1.8–3.0 with lower confidence intervals >1.0) and those who used GSM service (OR, 2.1; 95% confidence interval, 1.1–4.0). Myeloid leukemia (acute and chronic combined) was associated with benzene (OR, 3.9; 95% confidence interval, 1.3–11), a nonspecific group of other solvents (2.3; 1.1–4.9), occupational pesticides that were mostly unspecified (3.8; 2.1–7.1), and working with or near powerlines (4.3; 1.3–15). No associations were found for diagnostic X-rays, cigarette smoking, or other occupational exposures.     

Surveillance of subtype and genetic variation of the circulating strains of HIV-1 in Thailand

Two HIV-1 strains, CRF01_AE and subtype B', were reported in Thailand during the early years of the epidemic. Recently, an intersubtype recombination of HIV-1 strain was found in Thailand. Eight-hundred and twenty-eight samples collected during years 1995-2004 from high-risk groups in Bangkok, northern, northeastern, and southern region of Thailand were studied. HIV-1 env nucleotide sequences were used for phylogenetic analysis of the circulating HIV-1 strain. By single HIV-1 region (env) genotyping, CRFO1_AE was found in 97.3% and HIV-1 subtype B was found in 2.7%. A predominance of CRF01_AE was found in all geographic regions. Parallel analysis of the HIV-1 gag and env genes demonstrated that 2.1% and 4.0% of recombinant HIV-1 strains were found using p17 and p24 region sequences, respectively. The recombinant gag gene was also found in one southern isolate. Phylogenetic analysis of HIV-1 isolated from 20 provinces in 2002 suggested the northern and northeastern isolates were more related than the southern isolates which had the lowest genetic diversity of 0.13. The GPGQ V3 loop tip was also present in isolates from all regions. The molecular epidemiological data from this study may be useful for surveillance design as well as targeting prevention efforts. It also provides information regarding new antigenic regions of circulating strains responsible for the HIV-1 epidemic in Thailand.     

HIV-1 drug resistance in Thailand: before and after National Access to Antiretroviral Program.

BACKGROUND: The Ministry of Public Health (Thailand), MoPH, has had a program called National Access to Antiretroviral Program for People who have AIDS (PHA) or "NAPHA", to offer free antiretroviral drugs (ARV), which are locally produced in Thailand, to any HIV-1 infected patients with CD4<200 since 2002. This program may increase usage of ARV therapy and the emergence of HIV-1 drug resistance. OBJECTIVES: To monitor HIV-1 ARV drug resistant codon mutation in Thailand before and after the "NAPHA" program. MATERIALS AND METHODS: EDTA blood samples were collected from 542 HIV-1 infected subjects, who received ARV therapy in 1999 and 2001-2003, and perinatal chemoprophylaxis in 1998 and 2000. HIV-1 pol nucleotide sequences were analyzed. RESULTS: The percentage of drug resistant detection from the ARV therapy group in 1999 and 2001-2003 were 12.14 (34/280), 10.23 (9/88), 86.96 (20/23) and 57.55 (61/106), respectively. Of 332 NRTI drug resistant codon mutation, 226 (68.07%) were thymidine analogue mutations (TAMs). The percentage of TAMs detection in 1999 and 2001-2003 were 7.14 (20/280), 9.09 (8/88), 56.52 (13/23) and 43.34 (46/106), respectively. Of 105 NNRTI drug resistant codon mutation, 95 (90.48%) were related to nevirapine drug resistance. CONCLUSION: Thailand may need more appropriate monitoring of drug resistance in the free ARV therapy program to protect the future usage of drugs by minimizing the emergence of drug resistance.     

Sympatric occurrence of Taenia solium, T. saginata, and T. asiatica, Thailand

We confirmed sympatric occurrence of Taenia solium, T. saginata, and T. asiatica in western Thailand. DNA analysis of morphologically identified T. saginata, in a dual infection with T. solium, indicated it was T. asiatica. To our knowledge, this report is the first of T. asiatica and a dual Taenia infection from Thailand.