Sexual dimorphism of the twelfth thoracic vertebra for sex determination in the Central Thai population.

Analyzing skeletal remains is crucial for identifying individuals, and forensic anthropologists use this analysis to determine biological characteristics, particularly sex, aiding criminal investigations. Among thoracic vertebrae, the twelfth thoracic vertebra (T12) is highly sexually dimorphic in various populations. This study aims to establish a discriminant function equation (DFE) for sex determination based on T12 in the Central Thai population. A total of 15 parameters of T12 were examined in 69 bone samples (43 males and 26 females). Among the 15 parameters, 14 were significantly different between males and females. The discriminant function equation (DFE) was generated as DFE = -19.578 + 0.376(i) BDsm + 0.254(l) PW + 0.081TDm, with a cutoff value of -0.296 for males and females, showing 92.8 % accuracy. The evaluation of the DFE using 10 blind samples showed 90 % accuracy. These findings may offer an additional method for sex determination through T12, complementing the examination of other skeletal elements.

Distribution and Clinical Significance of Hepatitis B virus A1762T/G1764A Double Mutation in Chronic Hepatitis B Patients: A Cross-Sectional Study.

BACKGROUND: Chronic hepatitis B (CHB) is well-known as a major risk for liver cirrhosis and hepatocellular carcinoma (HCC). The A1762T/G1764A double mutation in the hepatitis B virus genome affects the production of HBe antigen and is established as a predictive marker for progression to HCC. Thus, this study aimed to investigate the prevalence and clinical significance of the mutation in Thai CHB patients. METHODS:  A cross-sectional study was conducted in 78 Thai CHB patients who were assessed for hepatitis B profiles, HBsAg, HBeAg and anti-HBeAg, transaminitis, liver fibrosis defined by FIB-4 (FIB-4) score and AST to platelet ratio index (APRI), alpha-fetoprotein (AFP) and active hepatitis B status. HBV A1762T/G1764A mutation was examined by SYBR Green I Real-time PCR. Chi-square and Mann-Whiney U tests were performed to determine the association between the mutation and variables. RESULTS: The prevalence of patients infected with the A1762T/G1764A mutation was 44.9%. The mutation was associated with HBeAg status (p=0.027) and HBsAg levels (p=0.008), transaminitis (p=0.011), and active hepatitis B (p=0.037), but not liver fibrosis markers, FIB-4 score and APRI, and AFP. Binary logistic regression identified the mutation as a predictive factor of active hepatitis B (OR 3.5, 95%CI, 1.1-11.3, p=0.037). Patients infected with the mutant exhibited significantly higher levels of HBsAg (p=0.011) and HBV viral load (p=0.047), but lower levels of HBeAg (p=0.12) than those infected with the wild-type HBV. CONCLUSION: The data indicate the high prevalence of the A1762T/G1764A mutation and its significant association with the severity of Thai CHB patients and the HBV mutation is proposed as a predictive marker of active hepatitis B status in CHB patients.

Prevalence and Risk Factors for Blastocystis Infection Among Children and Caregivers in a Child Care Center, Bangkok, Thailand.

In September 2009, a cross-sectional study was conducted to evaluate parasitic infections in a child care center in Khlong Toei, Bangkok, Thailand. Of 503 children and staff members, 258 (51.3%) stool samples and questionnaires were obtained. The most common parasitic infection was Blastocystis sp. (13.6%). Blastocystis sp. subtype 3 was predominantly found (80.0%), followed by subtypes 2 (12.0%) and 1 (8.0%). The prevalence of Blastocystis infection varied among different age groups. The prevalence of Blastocystis infection in non-HIV-infected children aged < 10 and 10-19 years were 14.5% and 10.3%, respectively, which were not significantly different. All 31 HIV-infected children were not infected with Blastocystis sp. The most likely reason could be the result of properly using prevention measures for this specific group.

Incidence and risk factors of blastocystis infection in orphans at the Babies' Home, Nonthaburi Province, Thailand.

BACKGROUND: Blastocystis infection is one of the most common intestinal protozoan infections reported in Thai population of all age groups for which epidemiological information is important to understand patterns of transmission for developing methods ofprevention and control for each specific group. The authors aimed to study prevalence, incidence and riskfactors associated with Blastocystis infection in orphans and childcare workers. Additionally, subtypes ofBlastocystis were identified MATERIAL AND METHOD: A retrospective cohort study of Blastocystis sp. was conducted in orphans aged less than 5 years and their childcare workers at Babies' Home, Nonthaburi Province, Thailand. A base line survey was conducted in December 2009 and afollow-up survey was conducted in April 2010. A total of 336 and 331 stool samples were collected. Blastocystis infection was examined using short-term in vitro cultivation in Jones's medium supplemented with 10% fetal calf serum. To analyze subtypes ofBlastocystis sp., PCR-RFLP of the small subunit ribosomal RNA gene was performed. RESULTS: Theprevalence ofBlastocystis infection in December 2009 and April 2010 were 8.1% and 13.3%, respectively The inlcidence rate ofBlastocystis infection was 1.6/100 person-months. Subtype analysis ofBlastocystis sp. in December 2009 and in April 2010 showed that subtype 3 was the most predominant (76% and 76%), followed by subtype 1 (16% and 20%), and unidentified subtype (8% and 4%), respectively. Subtype 3 is of human origin, thus person-to-person transmission is considered a major route ofBlastocystis infection in this population. CONCLUSION: Person-to-person transmission of Blastocystis infection in orphans living in the same house had been proposed, thus the prevalence and incidence of Blastocystis infection could be used to reflect the hygienic condition in the orphanage. Infection prevention and control practice can be effectively implemented.

Colicin type 7 produced by majority of Shigella sonnei isolated from Thai patients with diarrhoea

Thirty one out of 153 strains of Shigella sonnei isolated from Thai patients with diarrhoea showed antibacterial activity against S. sonnei by agar well diffusion method. All of them harbor plasmids with the genetic determination of colicin type 7 (Js) gene but without colicin E and colicin U gene. The PCR product obtained from strain 35/44 was shown to be the gene for colicin type 7 lytic protein (cja). The partially purified bacteriocin (PPB) containing colicin type 7 of strain 35/44 was prepared and used for characterization. The antibacterial activity of PPB against a total of 17 selected Gram-positive and Gram-negative bacteria was tested. It was found that PPB of strain 35/44 was active against E. coli O157, S. sonnei and S. boydii. The sensitivity of PPB from this strain to proteinase K, trypsin and α-chymotrypsin suggests the proteinaceous nature of these antimicrobial substances. Therefore, this isolated bacterium can be regarded as bacteriocin producing bacteria. The bacteriocin produced by this isolated S. sonnei was heat stable as evidenced by its ability to maintain the activity at 80 °C for 60 min. In addition, it was stable within a wide range of pH (3-9). The molecular weight of colicin type 7 from isolated S. sonnei strain 35/44 analyzed by SDS-PAGE was 54.4 kDa composing of at least five subunits. It is to our knowledge; the first report of Thai patients with diarrhoea that S. sonnei isolated from them contained colicin type 7.

Identification of Blastocystis subtype 1 variants in the Home for Girls, Bangkok, Thailand.

A cross-sectional study of Blastocystis infection was conducted to evaluate the prevalence, risk factors, and subtypes of Blastocystis at the Home for Girls, Bangkok, Thailand in November 2008. Of 370 stool samples, 118 (31.9%) were infected with Blastocystis. Genotypic characterization of Blastocystis was performed by polymerase chain reaction and sequence analysis of the partial small subunit ribosomal RNA (SSU rRNA) gene. Subtype 1 was the most predominant (94.8%), followed by subtype 6 (3.5%) and subtype 2 (1.7%). Sequence analyses revealed nucleotide polymorphisms for Blastocystis subtype 1, which were described as subtype 1/variant 1, subtype 1/variant 2. Blastocystis subtype 1/variant 1 was the most predominant infection occurring in almost every house. The results showed that subtype analysis of Blastocystis was useful for molecular epidemiological study.

Colicin type 7 produced by majority of Shigella sonnei isolated from Thai patients with diarrhoea.

Thirty one out of 153 strains of Shigella sonnei isolated from Thai patients with diarrhoea showed antibacterial activity against S. sonnei by agar well diffusion method. All of them harbor plasmids with the genetic determination of colicin type 7 (Js) gene but without colicin E and colicin U gene. The PCR product obtained from strain 35/44 was shown to be the gene for colicin type 7 lytic protein (cja). The partially purified bacteriocin (PPB) containing colicin type 7 of strain 35/44 was prepared and used for characterization. The antibacterial activity of PPB against a total of 17 selected Gram-positive and Gram-negative bacteria was tested. It was found that PPB of strain 35/44 was active against E. coli O157, S. sonnei and S. boydii. The sensitivity of PPB from this strain to proteinase K, trypsin and α-chymotrypsin suggests the proteinaceous nature of these antimicrobial substances. Therefore, this isolated bacterium can be regarded as bacteriocin producing bacteria. The bacteriocin produced by this isolated S. sonnei was heat stable as evidenced by its ability to maintain the activity at 80 °C for 60 min. In addition, it was stable within a wide range of pH (3-9). The molecular weight of colicin type 7 from isolated S. sonnei strain 35/44 analyzed by SDS-PAGE was 54.4 kDa composing of at least five subunits. It is to our knowledge; the first report of Thai patients with diarrhoea that S. sonnei isolated from them contained colicin type 7.

Incidence and risk factors of Blastocystis infection in an orphanage in Bangkok, Thailand.

BACKGROUND: Blastocystis sp. is one of the most common intestinal protozoa in humans. Unlike other intestinal parasitic infections such as giardiasis and cryptosporidiosis, the epidemiology of blastocystosis in children who live in crowded settings such as day-care centers and orphanages has been rarely explored. METHODS: A retrospective cohort study was conducted to evaluate incidence and risk factors of Blastocystis infection in an orphanage every two consecutive months during April 2003 to April 2004, in Bangkok, Thailand. Blastocystis sp. was identified using direct simple smear, and in vitro cultivation in Jones' medium. RESULTS: The incidence rate was 1.8/100 person-months and the independent risk factors associated with Blastocystis infection were age, nutritional status and orphans living in the room where their childcare workers were infected. CONCLUSIONS: Person-to-person transmission was most likely to occur either from orphans to childcare workers or from childcare workers to orphans living in the same room. Universal precautions such as regular hand washing and careful handling of fecally contaminated materials are indicated.