TB, HIV-associated TB and multidrug-resistant TB on Thailand's border with Myanmar, 2006-2007

Objective To measure the burden and improve management of tuberculosis (TB), HIV‐associated TB and MDR TB in Tak Province, Thailand, which borders Myanmar. Methods From September 2006 to August 2007, we collected uniform data about TB cases and enhanced human immunodeficiency virus (HIV) counselling and testing. We provided mycobacterial culture and drug‐susceptibility testing in public or non‐governmental organization facilities. Patients were classified by nationality and, for non‐Thais, by migration status. Results Of 1662 TB cases in the 12‐month period, 1087 (65%) occurred in non‐Thais. Of non‐Thais, 415 (38%) lived in Myanmar but crossed the border for healthcare. HIV infection was diagnosed in 18% of Thais compared with 12% of non‐Thais (P < 0.01); HIV status was unknown for 22% of Thais and 27% of non‐Thais (P = 0.02). Overall, multidrug‐resistant (MDR) TB was diagnosed in 27 patients, 19 (70%) in non‐Thais. Among TB cases never previously treated for TB, no MDR cases were diagnosed in Thais or in Myanmar refugees, but six cases were diagnosed in migrants from Myanmar. Conclusions In Thailand, TB, HIV‐associated TB and MDR TB in migrants from Myanmar are important public health problems; they need to be resolved in both the countries.     

Time-dependent Modulation of Liver Lesion Development in Opisthorchis-infected Syrian Hamster by an Antihelminthic Drug, Praziquantel

In the North-east of Thailand, repeated antihelminthic therapy has been introduced for control of the opisthorchiasis known to be a major risk factor for cholangiocellular carcinomas. What influence this may have on tumorigenesis, however, remains unclear. The effects of administration of praziquantel, an antihelminthic drug, at different time points subsequent to infection with Opisthorchis viverrini (OV) on 2,2'-dihydroxy-di- n -propylnitrosamine (DHPN)-initiated lesion development in the liver of female Syrian hamsters were therefore investigated. Praziquantel (250 mg/kg body weight, i.p.) was given 4, 12 or 20 weeks after infection of DHPN-treated animals (two 1000 mg/kg i.p. injections at weeks 0 and 2) with 60 OV metacercariae (at week 4). Survivors at week 38 were killed and examined. It was found that whereas praziquantel administration at the earlier two time points was effective at reducing hepatocellular nodule development, the results for cholangiocellular lesions were less pronounced, significant reduction only being evident in hamsters treated 4 weeks after parasite infestation. The findings thus indicate that enhancement of DHPN-initiated bile duct carcinogenesis by opisthorchiasis is both rapid and to a large degree irreversible. Hepatocellular lesion development in this model, on the other hand, appears to correlate more closely with the duration of parasite-associated proliferative stimulus.     

SHORT COMMUNICATION: Promotion of cholangiocarcinogenesis in the hamster liver by bile duct ligation after dimethylnitrosamine initiation

Administration of hepatocardnogenic nitrosamines before or afterinfection with the liver fluke, Opisthorchis viverrini (OV),results in marked development of cholangiocellular and hepatocellularprecancerous and cancerous lesions in the hamster liver. Thepromoting effects of OV are believed to be exerted either mechanically,chemically or immuno-logically. To test the influence of possiblemechanical effects, Syrian hamsters were initiated with a singlei.p. injection of dimethylnitrosamine (DMN) 20 mg/kg and subjected2 weeks later either to a sham operation or to complete ligationof the extrahepatic bile duct to the left lateral lobe. At theend of week 40, the animals receiving DMN-initiation and ligationhad a 60.9% incidence of cholangiofibrosis, 21.7% of mucouscystadenomas and 39.1% of cholangiocarcinomas, whereas the groupgiven DMN alone only developed cholangiofibrosis, limited to5% of the animals. In the latter case neither cystadenomas norcholangiocarcinomas were observed. The incidence of hepatocellularnodules did not differ between the two groups and no tumorouslesions developed in either the ligated or the untreated groupswithout DMN pretreatment. Complete ligation of the bile ductitself led to a series of events; obstruction of bile flow beingfollowed by dilatation, cyst formation, and necrosis of thebile duct epithelium and surrounding affected areas leadingto regenerative proliferation. The results are in line withthe conclusion that parasite-associated proliferation in targetcell populations is, at least in part, responsible for the influenceof OV on liver tumor development.     

Effects of Compliant Flooring on Dynamic Balance and Gait Characteristics of Community-dwelling Older Persons

The journal of nutrition, health & aging - Compliant flooring while providing the impact force attenuation in the event of falls, its low stiffness characteristic might impair balance and gait...     

Vibrotactile activation of the auditory cortices in deaf versus hearing adults

Neuroplastic changes in auditory cortex as a result of lifelong perceptual experience were investigated. Adults with early-onset deafness and long-term hearing aid experience were hypothesized to have undergone auditory cortex plasticity due to somatosensory stimulation. Vibrations were presented on the hand of deaf and normal-hearing participants during functional MRI. Vibration stimuli were derived from speech or were a fixed frequency. Higher, more widespread activity was observed within auditory cortical regions of the deaf participants for both stimulus types. Life-long somatosensory stimulation due to hearing aid use could explain the greater activity observed with deaf participants.     

Development of an airborne lead analysis kit and its application

We developed a method to analyze airborne lead concentrations in the field. It was a modification of the colorimetric method using the reaction between 4(2-pyridylazo)-resorcinol (PAR) and lead with cyanex302 in an acid medium to reduce interfering metals. The lead concentration was detected with a photometer made in Thailand. The developed method uses an impinger containing 1% nitric acid solution as an absorbing agent to collect airborne lead at a flow rate of less than or equal to one liter/minute. Cyanex302 solution in toluene was used to extract metals from the samples and 0.1M nitric acid was used to extract just lead. The lead solution was reacted in 0.5 ml of 0.03% PAR solution, with 1 ml ammonium chloride buffer; the absorption of this solution was measured by a photometer. The results show the limit of detection (LOD) was 0.01 mg/l. The limit of quantification (LOQ) was 0.03 mg/l. The percent recovery of the lead concentrations of 0.05 - 3.0 mg/l was 94.0 to 103.5%. The precision presented as %CV ranged from 0.65 to 10.27%. Lead concentration in a lead smelting factory detected by this method was not significantly different from that detected by the NIOSH method: 7,303 at a 95% confidence level.     

Influence of dehydroepiandrosterone, diaminopropane and butylated hydroxyanisole treatment during the induction phase of rat liver nodular lesions in a short-term system

The effects of concomitant treatment with dehydroepiandro-sterone,an inhibitor of glucose-6-phosphate dehydrogenase (G6PD), diaminopropane(DAP), an inhibitor of onuithine decarboxylase or the microsomaldrug detoxifying enzyme in-ducer butylated hydroxyanisole (BHA)during the induction phase of rat liver nodular lesion developmentwere investigated. Clear reductions in both number and sizeof foci and nodules as assayed quantitatively with the aid ofmarker enzymes G6PD, glutathione S-transferase P form or gamma-glutamyltranspeptidase were established for treatment with either DHEAor BHA. DAP in contrast did not exert influence on the numberof lesions, but brought about a significant reduction in size.The quantitative data taken together with the finding that increasedlabelling of tritiated thymidine occurred in extrafocal hepatocytepopulations in BHA-treated animals, give direct support to theview that alteration in enzyme phenotype within putative pre-neoplasticlesions plays a central role in their generation with this short-termmodel. In particular, a physiological adaptive significanceof G6PD elevation is suggested.     

Early lesions induced by DHPN in Syrian golden hamsters: influence of concomitant Opisthorchisinfestation, dehydroepiandrosterone or butylated hydroxyanisole administration

The effects of concomitant Opisthorchis infestation and dehydroepiandrosterone(DHEA) or butylated hydroxyanisole (BHA) administration on dihydroxy-di-n-propylnitrosamine(DHPN) induction of preneoplastic lesions were investigatedin Syrian golden hamsters. Whereas parasite infection was primarilyassociated with first-order ductular proliferation in the liverand a secondary appearance of cholangiofibrotic lesions, DHEAtreatment brought about increased carcinogen toxicity and enhancedgeneration of glutathione-S-transferase P (GST-P)-positive hepatocellularfoci, liver cysts and focal proliferative changes in the pancreas.BHA also exerted an enhancing influence on pancreatic but notliver carcinogenesis. The results suggest that whereas alterationof DHPN metabolism by DHEA and BHA treatment effected changesat the initiation level, opisthorchiasis principally exertedan enhancing influence subsequent to carcinogen withdrawal.     

Generation of High Yields of Syrian Hamster Cholangiocellular Carcinomas and Hepatocellular Nodules by Combined Nitrite and Aminopyrine Administration and Opisthorchis viverrini Infection

Combined administration of 0.1% nitrite and 0.1% aminopyrine in the drinking water for eight to ten weeks resulted in subsequent development of both hepatocellular nodules and cholangiofibrotic lesions/cholangiocellular carcinomas in Syrian golden hamsters. Additional prior dosing with Opisthorchis viverrini metacercariae (100/animal) induced inflammatory and proliferative changes in the livers of infected hamsters and was associated with a significant increase in yields of hepatocellular and cholangiocellular preneoplastic and neoplastic lesions. Thus, environmental factors thought to be casually related to the high levels of human liver cancer observed in the Northeastern provinces of Thailand were sufficient to bring about development of equivalent tumors in experimental animals. The results indicate that parasite associated liver injury and non-specific compensatory regeneration may play an important role in generation of both hepatocellular and cholangiocellular carcinomas in man.