Toward integrated opisthorchiasis control in northeast Thailand: The Lawa project

Human liver fluke, Opisthorchis viverrini, a food-borne trematode is a significant public health problem in Southeast Asia, particularly in Thailand. Despite a long history of control programmes in Thailand and a nationwide reduction, O. viverrini infection prevalence remains high in the northeastern provinces. Therefore, a new strategy for controlling the liver fluke infection using the EcoHealth/One Health approach was introduced into the Lawa Lake area in Khon Kaen province where the liver fluke is endemic. A programme has been carried using anthelminthic treatment, novel intensive health education methods both in the communities and in schools, ecosystem monitoring and active community participation. As a result, the infection rate in the more than 10 villages surrounding the lake has declined to approximate one third of the average of 50% as estimated by a baseline survey. Strikingly, the Cyprinoid fish species in the lake, which are the intermediate host, now showed less than 1% prevalence compared to a maximum of 70% at baseline. This liver fluke control programme, named “Lawa model,” is now recognised nationally and internationally, and being expanding to other parts of Thailand and neighbouring Mekong countries. Challenges to O. viverrini disease control, and lessons learned in developing an integrative control programme using a community-based, ecosystem approach, and scaling-up regionally based on Lawa as a model are described.     

The Case to Case Comparison of Hormone Receptors and HER2 Status between Primary Breast Cancer and Synchronous Axillary Lymph Node Metastasis

Background: Nowadays, the adjuvant treatment for breast cancer patients chosen depends on immunohistochemical pattern of Estrogen receptor(ER), Progesterone receptor(PR) and HER2 status of primary breast tumor. Several retrospective studies showed significant discordance in receptor expression between primary and metastatic tumors. The objective of this research was to determine discordant rate of ER, PR and HER2 status between primary breast cancer and synchronous axillary lymph node metastasis of individual breast cancer patients in Thammasat University Hospital. Methods: A prospective observational study of all breast cancer patients who have axillary metastasis and underwent surgery at Thammasat Hospital between January 2011 to December 2015. Tumor staging, ER, PR, and HER2 status on primary breast tumor were recorded. Synchronous axillary lymph node metastasis was evaluated with immunohistochemistry for ER, PR, and HER2. Results: The ER-positive rate from primary tumor to synchronous axillary lymph node metastasis decreased from 74.7% to 71.7%; the HER2 overexpression rate was decreased from 26% to 24%. In contrast, PR positive rate were 71% in both primary tumor and synchronous axillary lymph node metastasis. In case to case comparison, discordance rate of ER, PR and HER2 status between primary breast cancer and synchronous axillary lymph node metastasis were 11.1%, 20.2% and 10.1%, respectively. Furthermore, the tumor staging was not significant associated with discordance of ER, PR and HER2. Conclusion: ER, PR and HER 2 biomarkers showed significant concordance between primary tumor and synchronous axillary lymph node metastasis. Hence, if we cannot assess the ER, PR and HER2 status in primary tumor, then synchronous axillary lymph node metastasis can be studied instead. However, the repeat of biomarker testing in node-positive breast cancer patients may be beneficial for tailored adjuvant therapy, especially for patients with negative hormone receptor and/or HER2 profile on primary tumor.     

The immunogenicity and safety of pneumococcal conjugate vaccine in human immunodeficiency virus-infected Thai children

Background

HIV-infected children have high risk of invasive pneumococcal disease (IPD) despite receiving highly active antiretroviral therapy (HAART). This study aimed to determine the immunogenicity and safety of a 7-valent pneumococcal conjugate vaccine (PCV-7) in Thai HIV-infected children compared to HIV-exposed uninfected children.

Methods

A prospective study was conducted among children 2 months to 9 years. The number of PCV-7 doses depended upon age and HIV status; 2-6 months of age: 3 doses; 7-23 months of age: 2 doses; HIV-infected child ≥24 months: 2 doses and HIV-exposed child ≥24 months: 1 dose. Serotype-specific pneumococcal IgG antibody concentrations were measured at baseline and 28 days after complete vaccination. The primary end point was the proportion of children who achieved serotype-specific IgG antibody concentration at a cut off level ≥0.35 μg/mL. Secondary end points were a 4-fold increase in serotype-specific IgG antibody, rates of adverse events and predictors for seroconversion among HIV-infected children.

Results

Fifty-nine HIV-infected and 30 HIV-exposed children were enrolled. The median (IQR) age was 97 (67-111) and 61 months (51-73), respectively (p < 0.001). Among HIV-infected children, current and nadir CD4 counts were 1079 cell/mm³ and 461 cell/mm³, respectively. The proportion of children who achieved pneumococcal IgG ≥0.35 μg/mL was in the range of 85-98% in HIV-infected and 83-100% in HIV-exposed children depending on serotype. The lowest response was to serotype 6B in both groups. The 4-fold increase in serotype-specific IgG concentrations was similar between HIV-infected and HIV-exposed groups, except for serotype 9V (p = 0.027). HIV-infected children who had a history of AIDS had a lower antibody response to serotype 23F (p = 0.025). Seven (12%) HIV-infected children had a grade 3 local reaction.

Conclusion

PCV-7 is highly immunogenic and safe among HIV-infected children treated with HAART. The use of the pneumococcal conjugate vaccine among HIV-infected children is encouraged in order to prevent IPD.     

Mutations of KRAS and TP53 in a Minor Proportion of Opisthorchis Viverrini-Associated Cholangiocarcinomas in a Hamster Model.

Background/Aims KRAS oncogene and TP53 tumor suppressor gene have been known as common genesinvolving in many cancers including cholangiocarcinoma (CCC). Activation of these genes could lead touncontrolled proliferation and cancer ultimately. The aim of this study was to investigate mutation of KRASexon 1 and TP53 exon 5-8 in Opisthorchis viverrini (OV)-induced cholangiocarcinoma (CCA) in a hamster model.Methods: Twenty-seven CCAs were obtained from Syrian golden hamsters induced by OV infection and Nnitrosodimethylnitrosamine(N-NDDM) administration. The tumor tissues were processed for histopathology.Genomic DNA extracted from paraffin sections by microdissection was amplified for KRAS exon 1 and TP53exon 5-8 mutations by PCR-direct sequencing. Results Histopathologically, the tumors were classified into tubular(81.5%, 22/27), papillary (3.7%, 1/27), mucinous (3.7%, 1/27) and mixed types (11.1%, 3/27). Of the 27 CCAs,PCR-direct sequencing of KRAS showed G‡A transition at codon 37 exon 1 in one CCA sample (3.70%). Pointmutations of p53 exon 6 (G‡C transversion at codon 119 and 218 and A‡C transversion at codon 217) werefound in 3 CCA samples (11.1%). Conclusions: The results suggest that mutation of TP53 particularly at exon 6may be involved in cholangiocarcinogenesis and a novel mutation of KRAS exon 1 was firstly reported in OVinducedhamster CCA.     

The effect of base materials with different elastic moduli on the fracture loads of machinable ceramic inlays

This study investigated the effect of two base materials with different elastic moduli (F2000 and Vitrebond) on the fracture load of machinable ceramic inlays. Standardized MOD cavities were prepared in 18 human maxillary first or second premolars. The teeth were randomly assigned to three groups of six premolars each; Group 1 (control: no base); Group 2 (base with a polyacid-modified resin composite: F2000); Group 3 (base with a resin-modified glass-ionomer cement: Vitrebond). The inlays were fabricated from Vitablocs Mark II using a Cerec II machine. After the inlays were cemented with Tetric Ceram and the Syntac adhesive system, using the Ultrasonic Insertion Technique (USI), they were stored in distilled water at 37 degrees C for 24 hours prior to fracture testing in a universal testing machine using a crosshead speed of 0.5 mm/minute. The static transverse elastic moduli of base materials were measured using a three-point bending test. The mean fracture loads and standard deviations of the Cerec inlays in Groups 1, 2 and 3 were 1.15 +/- 0.39 KN, 1.13 +/- 0.36 KN and 0.58 +/- 0.11 KN, respectively. Statistical analysis showed that the mean fracture load of Group 3 was significantly lower than that of Groups 1 and 2 (p < .05). There was no significant difference in fracture load between Groups 1 and 2. The means and standard deviations of the elastic moduli of F2000 and Vitrebond were 15.63 +/- 0.32 and 2.16 +/- 0.55 GPa, respectively. The results indicated that the fracture load increased significantly as the elastic modulus of a base material increased.     

Appendicitis-like syndrome owing to mesenteric adenitis caused by Salmonella typhi

We report a 14-year-old girl who presented with signs of appendicitis and had her appendix removed. She subsequently proved to have mesenteric adenitis owing to Salmonella typhi which responded to treatment with ceftriaxone.