Effect of Temperature on the Killing of Opisthorchis viverrini Eggs In Vitro.

Contaminated liver fluke egg in the environment has led to the high prevalence of human opisthorchiasis associated with cholangiocarcinoma in Southeast Asia. To find the effective lessening methods of Opisthorchis viverrini eggs in the contaminated environment, we investigated the temperature conditions for killing of these trematode eggs in vitro. Numerous O. viverrini eggs were obtained in the proximal part of uteri of adult worms from experimental hamsters. Mature eggs with miracidium were allocated by experimental groups (2 control: positive and negative and 4 treatment: 50, 60, 70, and 80°C) with 0.85% saline, and treated by the experimental plan. Eggs in each experimental groups were observed under the confocal microscope after stain with Propidium Iodide (PI) to evaluate the effect of temperatures. Eggs in 70 and 80°C groups were all killed after over 10 min heated. Majority of eggs in 60°C (10, 15, and 30 min heated), 70 and 80°C (5 min heated) groups were inactivated. However in 50°C group, below half of eggs were to be killed in all time lapse (10, 15 and 30 min). In order to prevent O. viverrini infection and cholangiocarcinoma, direct treatment of sewage by heating at 70 or 80°C at least 10 min is essential. Therefore, treatment of O. viverrini eggs at a high temperature is a potential method for controlling egg contamination in sewage.

Significance of S100P as a biomarker in diagnosis, prognosis and therapy of opisthorchiasis-associated cholangiocarcinoma.

Cholangiocarcinoma (CCA) is a malignancy of bile duct with the difficulty in early diagnosis, poor prognosis and less alternation in therapy. S100P is a member of S100 family proteins and plays important roles in cancers. We investigated the S100P expression and its correlation with clinicopathology in 78 cases of opisthorchiasis-associated CCA, and the effects of S100P knockdown with shRNA interference on the proliferation, cell cycle, migration, apoptosis and sensitivity to anti-cancer drug. Extremely high expression of S100P mRNA was detected in the CCA tumor tissues. The increased S100P protein expression was immunohistochemically confirmed and localized in the CCA cytoplasm and/or nuclei as well as in the hyperneoplasia and dysplasia bile ducts, but not in normal bile ducts. The intensity of immunostaining was correlated with survival, tumor stage and metastasis, and the high expression could be an independent prognostic factor. High levels of S100P were detected in the serum and bile fluid of CCA patients. The shRNA-mediated knockdown of S100P expression inhibited the proliferation in vitro and in vivo, and migration of CCA cells, arrested cell cycle with the up-regulated expression of cell cycle arrest related factors, p21, p27, GADD45A, and 14-3-3 zeta. S100P knockdown also promoted CCA cell apoptosis by up-regulating expression of apoptosis related factors, DR5, TRADD, caspase 3 and BAX, and increased the sensitivity of CCA cells to the chemotherapeutic agents sunitinib and apigenin. Taken together, this study indicates that S100P might be a promising biomarker for the diagnosis, prognosis and therapy of CCA.

A combination of liver fluke infection and traditional northeastern Thai foods associated with cholangiocarcinoma development.

Opisthorchis viverrini infection is one of the risk factors for cholangiocarcinoma (CCA) in northeast Thailand, a region with one of the highest reported incidence rates of CCA. The traditional practice of eating raw fish, repeated exposure to liver flukes, and consumption of nitrosamine-contaminated food are major risk factors for CCA. So far, there have been no reports about which northeastern traditional dishes may be involved in CCA development. The present study, thus, investigated the effects of traditional foods. It focused specifically on the consumption of fermented foods in combination with O. viverrini infection in hamsters. Syrian hamsters were divided into six groups: (i) normal hamsters, (ii) O. viverrini infection only and (iii)-(vi) O. viverrini infection plus fermented foods (pla som-fish fermented for 1 day), som wua-fermented beef, som phag-fermented vegetables, and pla ra-fish fermented for 6 months. Syrian hamster livers were used for analysis of histopathological changes through hematoxylin and eosin; Sirius Red; and immunohistostaining for cytokeratin-19, proliferating cell nuclear antigen, and CA19-9. Hamster sera were used for liver and kidney function tests. Results of all O. viverrini-infected groups and fermented food groups showed that histopathological changes consisted primarily of aggregations of inflammatory cells surrounding the hepatic bile duct, especially at the hilar region. However, there was a difference in virulence. Interestingly, aggregations of inflammatory cells, new bile duct formation, and fibrosis were observed in subcapsular hepatic tissue, which correlated to positive immunohistochemical staining and increased liver function test. The present study suggests that fermented food consumption can exacerbate cholangitis and cholangiofibrosis, which are risk factors for cholangiocarcinoma-associated opisthorchiasis.

Simplified Berlin Questionnaire for Screening of High Risk for Obstructive Sleep Apnea Among Thai Male Healthcare Workers.

Obstructive Sleep Apnea (OSA) is a common disease associated with major cardiovascular diseases. Male subjects are more at higher risk for OSA than female subjects. The Berlin questionnaire is a beneficial screening tool for OSA and has 14 items. The Berlin questionnaire may need some adjustment for Thai or Asian populations. We aimed to find items that should be asked in the Berlin questionnaire to identify high risk for obstructive sleep apnea among Thai male healthcare workers. This study was performed in Thai male healthcare workers over the age of 35 and currently working at the Faculty of Medicine, Khon Kaen University. The Thai version of the Berlin questionnaire was randomly distributed. A study population of 273 subjects was required to provide a confidence value of 95%. An item analysis of the Berlin questionnaire was evaluated as independent factors for being high risk of OSA by using a multivariate logistic regression analysis. Of the 273 distributed questionnaires, 135 subjects returned then (49.5% response rate). Of those, 41 (30.4%) were identified as being at high risk of OSA. Only three items of the Berlin questionnaire, including frequent snoring, high body mass index and hypertension, were independently associated with being at high risk for OSA. In conclusion, the Berlin questionnaire can be shortened to identify high risk for OSA by itself; not polysomnography.

Anthelmintic, anti-inflammatory and antioxidant effects of Garcinia mangostana extract in hamster opisthorchiasis.

Administration of praziquantel for treatment of liver fluke infection may affect the host, with mild and severe effects after treatment caused by host immune response. Therefore, we focused on the antioxidant property, inflammatory and anthelmintic effects of the traditional folk medicine, G. mangostana pericarp extract, in hamster opisthorchiasis. Syrian hamsters were divided into four groups: normal (control) (N); administered G. mangostana alone (GM); infected with Opisthorchis viverrini alone (OV); and infected with O. viverrini and administered G. mangostana extract for 1.5 months (OVGM). Hamster livers were collected 45 days after infection to determine histopathological changes, i.e. aggregation of inflammatory cells. The morphology of adult O. viverrini (body size and sizes of reproductive organs) was analyzed, as well as worm burden, eggs per worm and eggs per gram of feces. Toxicity was tested by kidney function (blood urea nitrogen and creatinine); the results demonstrated that G. mangostana had no renal toxic effect. ABTS radical-scavenging assay indicated that the extract had antioxidant property. Reduction in aggregation of inflammatory cells surrounding the hepatic bile duct, especially at the hilar region, was found in the OVGM group. Worm burden was similar in both infected groups (treated or untreated with G. mangostana), but the average size of adults in the OV group was larger than in the OVGM group; moreover, eggs per worm and eggs per gram of feces were also comparatively higher. The present study suggests that G. mangostana extract possesses anti-inflammatory and antioxidant properties and can interfere with parasite development by affecting adult size and egg production. This may be useful for controlling the spread of OV infection and other parasites in endemic areas.

Work-Related Quality of Life among Medical Residents at a University Hospital in Northeastern Thailand.

OBJECTIVE: 1) To assess work-related quality of life (WRQOL) among medical residents at a university hospital in northeast Thailand. 2) To determine the strength of the association between personal and working condition components and WRQOL among medical residents. MATERIAL AND METHOD: A descriptive study was used to describe the WRQOL among medical residents. The study population comprised of all 375 residents affiliated with the university hospital. The Thai version of a self-administered work-related quality of life scale-2 was used for data collection. RESULTS: Testing the reliability revealed a Cronbach's alpha of 0.908. Questionnaires were completed by 259 of 375 (68.3%). The study found that the mean rating by residents for overall WRQOL was 113.8 out of 170 (SD 14.8). Most rated WRQOL as moderate (76.6%). The seven sub-factors were rated as moderate to high for employee engagement and control at work, moderate for home/work interface, general well-being and working conditions, high-moderate for job career satisfaction, and low-moderate for stress at work. Relationships between the personal and working condition components and WRQOL were analyzed using binary logistic regression. Residents in minor specialties had a higher WRQOL than those in major specialties (OR 2.522, 95% CI: 1.37, 4.63). Residents who had less than eight duty shifts/week had a higher WRQOL than those with more than eight duty shifts/week (OR 2.263, 95% CI: 1.16, 4.41). Similarly, residents working with less than 80 hours/week had a higher WRQOL than those working more than 80 hours/week (OR 2.344, 95% CI: 1.17, 4.72). A subgroup analyzes of those working in minor specialties showed the trend that working less than eight shifts/month and working less than 80 hours/week had the potential association with good quality of work-life (QWL). This phenomenon is presented in the subgroup analyses of those working in major specialties. Therefore, working hours and number of shifts might have played important role in contributing good QWL. CONCLUSION: To increase QWL, the residents and institutions should be better managed to have the appropriate number of working hours and to increase work-life balance, working condition, general well-being, and job-career satisfaction. On the other hand, stress at work must be reduced.

Sex differences in opisthorchiosis and the development of cholangiocarcinoma in Syrian hamster model.

Worldwide, the highest incidence of cholangiocarcinoma (CCA) is found in northeast Thailand, the endemic area of Opisthorchis viverrini infection. Cumulated clinical data revealed that the majority of CCA patients are men. However, many other types of cancers are more commonly found in women. In this study, we investigated the sex differences in the development of CCA, induced by O. viverrini infection and N-nitrosodimethylamine administration, in Syrian hamsters. Histopathology, liver function tests, and fecal egg counts were analyzed. The results showed that there are no sex differences in hamsters responses to O. viverrini infection and no prevalence of CCA development. Even though serum ALT level in O. viverrini-infected or CCA hamsters was significantly increased in female compared to male (p < 0.05) and uninfected control (p < 0.05), our results may imply that the higher prevalence of opisthorchiasis and CCA in men than in women in northeast Thailand may depend on behaviors of an individual exposed to risk factors rather than gender difference.

Molecular detection and treatment of tick-borne pathogens in domestic dogs in Khon Kaen, northeastern Thailand.

We determined the prevalence of tick-borne pathogens in domestic dogs using microscopy and polymerase chain reaction (PCR) techniques. A total of 303 EDTA blood samples were collected from domestic dogs in Khon Kaen Province, Thailand, in May 2013. Microscopic observation of Giemsa-stained smears and molecular diagnosis using conventional PCR were performed. Infected dogs were treated with imidocarb dipropionate, a combination of imidocarb dipropionate and doxycycline, or doxycycline alone. Seventy-one (23.4%) out of 303 dogs were positive for DNA of tick-borne pathogens. Of the 303 animals, 13.2% and 1.3% were positive for a single infection with Babesia spp or Ehrlichia canis, respec- tively using microscopy; whereas 19.5% and 3.0% were positive using the PCR technique. Co-infection with Babesia spp and E. canis was observed in 0.7%, and coinfection with Hepatozoon canis and E. canis in 0.3%. Infected dogs were treated with the assigned drugs, and elimination of the pathogens was demonstrated by microscopy and PCR. The results indicated that while both microscopic and PCR diagnostic techniques were useful for tick-borne pathogen detection, PCR was more effective. Imidocarb dipropionate and doxycycline were found to be effective for treatment of babesiosis and ehrlichiosis, respectively. The present study suggests that the PCR technique has high sensitivity and specificity for Babesia and Ehrlichia diagnosis as well as for detection of Babesia spp, E. canis and H. canis DNA in EDTA blood specimens.

Does a combination of opisthorchiasis and ethyl alcohol consumption enhance early cholangiofibrosis, the risk of cholangiocarcinoma?

Combination of Opisthorchis viverrini infection and other factors could drive cholangiocarcinoma (CCA) development in Southeast Asia. However, other CCA factors are obscure. Alcohol consumption is well known in the risk for several cancers, but there is no report in CCA development. Therefore, the present study was to clarify whether drinking alcohol increases the liver pathology of Opisthorchis viverrini (OV) infection which may be the CCA risk. Experimental Syrian hamsters were divided into two groups: (1) infected with OV alone (OV); and (2) infected with OV plus administration of drinking alcohol (OV + ALC) for various lengths of time, i.e., 1, 2, 3, and 6 months. Hamster livers were collected for analysis of histopathological changes through hematoxylin and eosin, Sirius red, and immunohistostaining for proliferating cell nuclear antigen (PCNA) and cytokeratin 19 (CK19). Syrian hamster sera were used for liver function tests. Observed histopathological changes consisted primarily of aggregations of inflammatory cells surrounding the hepatic bile duct, especially at the hilar region, in both OV and OV + ALC groups; however, there was a difference in virulence. The OV + ALC group showed greater severity than the OV group. Moreover, in addition to aggregations of inflammatory cells, new bile duct formation (including hepatic cell death) was observed in subcapsular hepatic tissue. Bile duct proliferation, as determined by positive immunohistochemical staining for CK19 and PCNA, was correlated with the histopathology. Increased fibrosis was observed in subcapsular liver tissue. The present study suggests that alcohol consumption can exacerbate cholangiofibrosis, cholangitis, and lithiasis, which are risk factors for CCA.

A cross-sectional study on intestinal parasitic infections in rural communities, northeast Thailand.

Despite the existence of effective anthelmintics, parasitic infections remain a major public health problem in Southeast Asia, including Thailand. In rural communities, continuing infection is often reinforced by dietary habits that have a strong cultural basis and by poor personal hygiene and sanitation. This study presents a survey of the prevalence of intestinal parasitic infections among the people in rural Thailand. The community-based cross-sectional study was conducted in villages in Khon Kaen Province, northeastern Thailand, from March to August 2013. A total of 253 stool samples from 102 males and 140 females, aged 2-80 years, were prepared using formalin-ethyl acetate concentration methods and examined using light microscopy. Ninety-four individuals (37.2%) were infected with 1 or more parasite species. Presence of parasitic infection was significantly correlated with gender (P=0.001); nearly half of males in this survey (49.0%) were infected. Older people had a higher prevalence than younger members of the population. The most common parasite found was Opisthorchis viverrini (26.9%), followed by Strongyloides stercoralis (9.5%), Taenia spp. (1.6%), echinostomes (0.4%), and hookworms (0.4%). The prevalence of intestinal protozoa was Blastocystis hominis 1.6%, Entamoeba histolytica 0.8%, Entamoeba coli 0.8%, Balantidium coli 0.4%, Iodamoeba bütschlii 0.4%, and Sarcocystis hominis 0.4%. Co-infections of various helminths and protozoa were present in 15.9% of the people. The present results show that the prevalence of parasitic infections in this region is still high. Proactive education about dietary habits, personal hygiene, and sanitation should be provided to the people in this community to reduce the prevalence of intestinal parasite infections. Moreover, development of policies and programs to control parasites is needed.

Monks: A Population at Risk for Liver Fluke and Skin-Penetrating Helminths.

Monks cannot cook received raw meat dishes and should walk barefoot while working. This population lacks both a survey of parasitic infection and a proper prevention and control policy. Five hundred and fourteen monks from the Ubolratana, Ban Haet, and Ban Phai Districts of Kh on Kaen Province were enrolled in this study. A stool container and questionnaire were collected from each study participant. Stool samples were processed by formalin ethyl acetate concentration and agar plate culture techniques. We then analyzed the results and risk factors to demonstrate associations. The prevalence of overall parasites, liver flukes, and skin-penetrating helminths were 28.8%, 11.1%, and 19.3%, respectively. Raw fish dish offerings were associated with opisthorchiasis (ORcrude 3.32; 95% CI 1.53-7.20). The risk factors for skin-penetrating helminths were older age (ORcrude 5.02; 95% CI 2.2-11.17), being a long-term ordinate (ORcrude 3.28; 95% CI 1.15-9.34), smoking (ORcrude 2.03; 95% CI 1.23-3.36), and chronic kidney disease with other underlying disease (ORcrude 20.7; 95% CI 2.54-190.1). The protective factors for skin-penetrating helminths were secular education above primary education (ORcrude 0.41; 95% CI 0.25-0.65) and having received health education about parasitic infection (ORcrude 0.47; 95% CI 0.28-0.80). Wearing shoes at times other than alms work does not show a protective effect against skin-penetrating helminths (ORcrude 0.86; 95% CI 0.51-1.46). These findings support the recommendation for a strict Rule of Discipline regarding raw meat ingestion and allowing shoes to be worn for protection against skin-penetrating helminths in high-risk situations.

Reduction of carcinogens in fermented fish (pla-ra and pla-som) by heating.

Background and Aim: The risk factors for cholangiocarcinoma (CCA) are opisthorchiasis and the intake of a combination of nitroso compounds through the consumption of traditionally fermented fish, which is very popular in areas where liver flukes are endemic. The incidence of CCA remains high because this cultural habit of rural people has been altered. Therefore, decreasing nitrate and nitrite concentrations in fermented fish are an alternative approach to reducing the risk of CCA. Thus, this study aimed to reduce nitrate and nitrite concentrations in fermented foods by heating and investigated its effect on CCA development in a hamster model. Materials and Methods: We used Association of Official Analytical Chemists method 973.31 to measure the nitrate and nitrite concentrations in both fermented fish (pla-ra [PR]) and pickled fish (pla-som [PS]) before and after boiling for 5 and 30 min, respectively. The same samples were fed to Opisthorchis viverrini (OV)-infected or -uninfected hamsters for 3 months. Thereafter, the hamsters' liver and blood were collected for analysis. Results: The levels of nitrates and nitrites in PS and PR significantly decreased following boiling for 5 and 30 min. The OV-PR and OV-PS groups showed dramatically increased numbers of inflammatory cells, fibrosis surrounding the bile duct, and focal fibrotic areas. However, after boiling the fermented dishes for 5 and 30 min, the extent of inflammatory cell infiltration and intensity of fibrosis in these groups were decreased. Conclusion: Our findings suggest that boiling reduces nitrate and nitrite toxicity in fermented dishes, as evidenced by reduced hepatic inflammation. However, regardless of heating, kidney tissues are adversely affected when fermented meals are consumed daily.

Alteration of galectin-1 during tumorigenesis of Opisthorchis viverrini infection-induced cholangiocarcinoma and its correlation with clinicopathology.

Galectin-1 is a beta-galactoside-binding lectin to function in cell adhesion, proliferation, differentiation, and might be involved in tumor progression and metastasis. In the present study, the expression kinetics of galectin-1 during the tumorigenesis of a parasite Opisthorchis viverrini infection-induced cholangiocarcinoma (CCA) was investigated in model animal hamsters, and the expression was confirmed in human CCA cases. It was found that galectin-1 was overexpressed at mRNA and protein levels with the tumor progression. The mRNA expression was elevated in very early stage during tumorigenesis and the increase was time dependent. Galectin-1 protein expression profiles indicated that the increased expression was mainly located in the epithelium of extensively proliferated and hyperplasia small bile ducts at early stage of CCA development in model animal and mainly in the extensive tumor stroma tissues in both model animals and human CCA cases at later stage. The analysis of correlation of the overexpression with clinicopathology in human cases suggested that high expression of galectin-1 was associated with advanced stage and metastasis and with shorter cumulative overall survival of the patients. Multivariate Cox regression analysis revealed that galectin-1 expression was of independent prognostic significance for CCA. Our results suggest that galectin-1 is likely involved in the tumorigenesis and expected to serve as a tumor stroma marker in diagnosis and prediction of metastasis and poor prognosis of the opisthorchiasis-associated CCA.

Platelet-derived growth factor may be a potential diagnostic and prognostic marker for cholangiocarcinoma.

Our previous report showed that platelet-derived growth factor (PDGF) and related genes were upregulated in a Syrian hamster model and could be detected in all human cholangiocarcinoma (CCA) tissues. We therefore hoped that PDGF could be used as a diagnostic and prognostic marker. We analyzed 78 samples of human CCA and adjacent tissues for PDGF and related gene expression, and localized PDGF protein expression. The mechanism of anti-cancer drugs on PDGF and related genes or proteins in CCA cell lines (OCA17, M156, and KKU100) was studied through MTT cell viability assay, quantitative real-time PCR, and immunoblotting. Mutagenesis of the PDGFRA coding region was analyzed. Moreover, the PDGFRA in sera of CCA patients and healthy controls was investigated. PDGFA was found to be upregulated in CCA tissue (84.6 %). Positive PDGFA immunohistochemical staining was significantly correlated with status (P = 0.000), stage of CCA (P = 0.013), metastasis (P = 0.017), and short survival rate (P = 0.005), and the multivariate analysis confirmed that PDGFA positive immunostaining had a higher likelihood of the risk of death (HR = 2.907, P = 0.016). For DNA point mutation of the PDGFRA sequence, silent mutations were found at tyrosine kinase 2 V824V (exon 18) and A603A (exon 13), and a missense mutation in S478P (exon 10); there was only a missense mutation in S478P (29 %) that has significant correlation with the histopathological grading (P = 0.037) and positive immunoreactive PDGFA (P = 0.021). In vitro cell line study by immunowestern blotting found that sunitinib malate had an inhibitory effect on the PDGFA pathway by decreasing p-PDGFRA, AKT, and p-AKT expression. The serum level of PDGFA in CCA patients was significantly higher than those of healthy control by 1.4-fold (P = 0.014). The present results suggest that PDGFA and PDGFRA may be used for CCA prognosis and/or as diagnostic candidate markers.

Comparative studies on animal models for Opisthorchis viverrini infection: host interaction through susceptibility and pathology.

Syrian hamsters and gerbils are animal models for Opisthorchis viverrini infection. In both models, the parasites develop into adults with different pathologies of the hepatobiliary system. However, no comparative pathological studies have yet been completed. We therefore investigated host interaction through the susceptibility and pathological changes of Syrian hamsters and gerbils infected with 50 O. viverrini metacercariae for 30, 60, and 90 days post-infection. Animals were sacrificed at each time point for comparative study. Susceptibility and infectivity were investigated through worm burden. Parasite morphology and reproductive organs were stained with carmine and observed under light microscopy. Reproductive organs and eggs per worm were counted to confirm worm maturity. Bile acid components of both animal groups were analyzed by thin-layer chromatography. The results showed that infection in gerbils was of greater severity than in Syrian hamsters by observation of bile obstruction, enlargement of the gallbladder and common bile duct, and generation of fibrosis and cirrhosis. The worm burden of infected gerbils was lower than that observed in Syrian hamsters. Infectivity in both Syrian hamsters and gerbils was 100% with infection by 50 metacercariae; whereas with 10 metacercariae, the infectivity in gerbils was zero to very low, but still 100% in Syrian hamsters. The largest body size of worms, and the largest ovary and testes areas, was correlated with eggs per gram of feces and eggs per worm. The bile acid components cholic acid and chenodeoxycholic acid were undetectable in gerbils. The present study suggests that although Syrian hamsters, usually the host selection for an animal model, are susceptible to O. viverrini infection, infected gerbils produce worms that mature more rapidly, have larger body sizes, and more fully developed reproductive organs; this may be caused by the difference in bile acid components.

Prevalence and Associated Risk Factors of Intestinal Parasitic Infections: A Population-Based Study in Phra Lap Sub-District, Mueang Khon Kaen District, Khon Kaen Province, Northeastern Thailand.

Intestinal parasitic infections are still a crucial problem among communities in Northeast Thailand. Misuse of antiparasitic drugs and unhealthy food behaviors are known. This study aimed to explore the prevalence, behavioral health factors, and motivation for self-treatment of anti-parasitic drugs in this area. A community-based cross-sectional study was conducted in Phra Lap sub-district, Mu Khon Kaen district, Khon Kaen province, Northeast Thailand, in 2016. A total of 419 participants were recruited to complete a self-administered questionnaire and stool examination. Binary logistic regression was used to assess the association between the risk factor and parasitic infection. Forty-two participants (10%; 95%CI 7.5-13.3) were positive for at least one parasite species. In this community, the most detected intestinal parasite was Opisthorchis viverrini (5.3%), followed by Strongyloides stercoralis (3.1%). A total of 67.5% of the participants had the experience of anti-parasitic drug treatment within previous 1 year, and "Often eat raw food" was the most common reason for the use of anti-parasitic drugs. On multivariate analysis, parasitic infections were significantly associated with male gender (ORadj. 2.42; 95%CI 1.00-5.85), age ≥ 60 years (ORadj. 7.55; 95%CI 1.60-35.76), and often consuming raw food of at least one type (ORadj. 2.37; 95%CI 1.03-5.44). Given these findings, correction of the dietary habit of eating raw fish/meat, which is the most important measure, and limitation of the use of anthelmintic treatment for individuals with stools positive for ova as well as emphasis on sanitary toilets will be implemented for the prevention and control of parasitic infection in endemic communities.

Indirect effect of a turmeric diet: enhanced bile duct proliferation in Syrian hamsters with a combination of partial obstruction by Opisthorchis viverrini infection and inflammation by N-nitrosodimethylamine administration.

The present study revealed the indirect effect of a turmeric (TUR) diet on the histopathological changes and proliferating cell nuclear antigen staining in Syrian hamsters with partial obstruction by liver fluke (Opisthorchis viverrini) infection and inflammation by N-nitrosodimethylamine (NDMA) administration. The result of the analysis of histopathological changes shows that a TUR diet has an anti-inflammatory property in the case of a single condition of NDMA administration or O. viverrini infection, as has been reported previously. Unfortunately, an adverse indirect effect of TUR was observed in the combination of infection with O. viverrini and administration of NDMA, with a 30-50% increase in new bile duct formation, correlated with an increase in proliferating cell nuclear antigen. Our present result suggests that the properties of curcumin are anti-inflammation and antioxidant including enhancing biliary contraction and bile flow. Thus, a combination of factors (treated with O. viverrini, NDMA, and TUR diet) result in an increasing bile duct proliferation which may cause from biliary homeostasis.

Opisthorchis viverrini infection causes liver and biliary cirrhosis in gerbils.

Opisthorchis viverrini infection causes many hepatobiliary diseases, including cholangiocarcinoma. Hence, the study of O. viverrini infection in humans is subject to ethical limitations, so an animal model, the Syrian hamster, is often used. O. viverrini can develop into the adult stage not only in Syrian hamsters but also in other animals, including gerbils, but until now, there has been no report on pathology and susceptibility in gerbils. The present study revealed the pathology of O. viverrini infection in gerbils through gross appearance, histopathology, and worm recovery at various time points. Gerbils were infected with 50 O. viverrini metacercariae and then sacrificed at the time of observation. The gross appearance of the liver showed micronodules at the liver surface, suggesting liver and biliary cirrhosis. Light microscopic observation was correlated to the gross appearance with cholecystitis, fatty liver changes, fibrous septa, and generalized cirrhosis. The range of worm burden fluctuated from 1 to 25 worms with large body size, which was correlated with pathology. These novel findings indicate that O. viverrini infection can cause liver and biliary cirrhosis in gerbils, depending on the worm burden, worm size, and habitat.

Candidate genes involving in tumorigenesis of cholangiocarcinoma induced by Opisthorchis viverrini infection.

Opisthorchiasis-associated cholangiocarcinoma (CCA) is one of main public health problems in Opisthorchis viverrini endemic areas. Although the definite relationship between prevalence of CCA and the parasite infection has been demonstrated, the molecular mechanism of tumorigenesis is still unknown. In the present study, by using animal model of opisthorchiasis-associated CCA, a kinetic analysis of cDNA microarray was performed to screen the candidate genes that involve in the development of opisthorchiasis-associated CCA. Microarray analysis revealed that the expressions of 131 genes were up-regulated during the development of CCA, including the genes relative to cell proliferation, differentiation and transformation, cell growth and cycle regulation, apoptosis, DNA repair, and cytoskeletal structure. The expressions of 145 genes were down-regulated, including the genes relative to metabolic enzymes, tumor suppressor, apoptosis, and oxidative response and oxidation reduction. The present study listed up the candidate genes involving tumorigenesis, provided molecular information on the development of opisthorchiasis-associated CCA and the potential biomarkers for diagnosis and therapy, and suggested that the increased expression of cell differentiation, proliferation, transformation-related genes, and decreased expression of metabolic enzymes may play important roles in the tumorigenesis of CCA.

Efficacy of Dipterocarpus alatus oil combination with Rhinacanthus nasutus leaf and Garcinia mangostana pericarps against canine demodicosis.

BACKGROUND AND AIM: Canine demodicosis is a skin disease that is a major global health problem in dogs. Ivermectin is a drug of choice for treatment, but it may cause toxicity in dogs carrying multidrug resistance mutation-1 gene mutations. Hence, alternative herbal medicines are used instead of the drug, such as Dipterocarpus alatus oil (YN oil), Rhinacanthus nasutus leaf (WC), and Garcinia mangostana pericarps (MG) extracts. This study aimed to determine the efficacy of D. alatus oil, R. nasutus leaf, and G. mangostana pericarp extracts on canine demodicosis in vivo. MATERIALS AND METHODS: Twenty-five mixed-breed dogs with localized demodicosis were examined. Dogs were diagnosed with demodicosis through deep skin scraping and screened with the inclusion criteria. Five dogs of each group were treated in five treatment groups (ivermectin, YN oil, YN oil+WC, YN oil+MG, and YN oil+WC+MG) for 1 month. The individual dogs were clinically evaluated, and the dermatological lesions were monitored daily for 60 days. RESULTS: Dermatological lesion improvement was predominantly observed in the group of dogs treated with YN oil+WC. This was evidenced by the disappearance of the hyperpigmentation and lichenification on day 28 post-treatment and alopecia on day 56 post-treatment. Moreover, no allergic or clinical signs were observed during treatment. CONCLUSION: YN oil+WC is an alternative herbal medicine that could be used for the treatment of localized canine demodicosis.