Dose-dependence of promotion of 2-amino-3,8-dimethylimidazo[4,5-f]quinoxaline-induced rat hepatocarcinogenesis by ethanol: evidence for a threshold

Although ethanol is thought to be a tumor-promoter, there are conflicting results concerning its effects on experimental hepatocarcinogenesis. Furthermore, the relationship between the amount of ethanol consumed and tumor promoting effects has hitherto not been investigated in detail. In the present study, 21-day-old F344/DuCrj rats were fed 200 p.p.m. 2-amino-3,8-dimethylimidazo[4,5-f]quinoxaline (MeIQx) in their diet for 8 weeks and thereafter received ethanol at doses of 0, 0.1, 0.3, 1, 3, 10 and 20% in drinking water ad libitum for 16 weeks. The incidences of hepatocellular adenoma and total tumors increased dose-dependently with statistical significance at doses of 10% and 20%, compared to the initiated control value. Similarly, dose dependence was observed for the incidence of hepatocellular carcinoma, which was elevated significantly at the dose of 20%. No alteration in development of preneoplastic glutathione-S-transferase placental form positive foci or tumors was observed with 0.1-1%. Cell proliferation also increased dose-dependently and CYP2E1 protein induction was recognized in centrilobular regions without alteration in mRNA levels, but no effects were evident on formation of 8-hydroxy-2'-deoxyguanosine, an oxidative DNA damage marker, or lipid peroxidation in any of the initiated groups. The mRNA expression of cyclin D1 increased dose dependently. The results demonstrated that ethanol dose-dependently promotes hepatocarcinogenesis induced by MeIQx, but with no adverse influence at doses of 1% or less, comparable to sensible drinking levels in humans.     

A Non-Probiotic Fermented Soy Product Reduces Total and LDL Cholesterol: A Randomized Controlled Crossover Trial

Traditional Asian fermented soy food products are associated with reduced cardiovascular disease risk in prospective studies, but few randomized controlled trials have been conducted in at-risk populations. The aim of this study was to investigate the effect of a commercial non-probiotic fermented soy product on blood lipids in adults with cardiovascular risk biomarkers. In a randomized, crossover, intervention study, 27 men and women (aged 29–75 y) exhibiting at least two risk factors, consumed two packets (12.5 g each) daily of a fermented powdered soy product, or an isoenergic control powder made from germinated brown rice for 12 weeks each. The consumption of the fermented soy product resulted in a significantly greater mean change from baseline (compared to the germinated rice, all p < 0.05) in total cholesterol of −0.23 mmol/L (CI: −0.40, −0.06) compared with 0.14 mmol/L (CI: −0.03, 0.31), respectively; and low density lipoprotein (LDL) cholesterol −0.18 mmol/L (CI: −0.32, −0.04) compared with 0.04 mmol/L (CI: −0.01, 0.018) respectively. This was accompanied by an increase in high density lipoprotein (HDL) cholesterol in the germinated rice group, a decrease in apolipoprotein B (ApoB) in the fermented soy group, and a between-treatment effect in apolipoprotein A1 (ApoA1); however, the ratio of the LDL:HDL and of Apo B:ApoA1 did not differ between the groups. The ratio of total cholesterol:LDL decreased in men in the fermented soy group (p < 0.001). Twenty-four-hour urine collection at the end of each treatment period resulted in an increased excretion expressed as a ratio in μmol/d between treatments of 10.93 (CI: 5.07, 23.54) for daidzein; 1.24 (CI: 1.14, 4.43) for genistein; and, 8.48 (CI: 4.28, 16.80) for glycitein, all p < 0.05. The fermented soy powder consumed by participants in this study without implementing other changes in their typical diets, decreased the total and LDL cholesterol, and may serve as a dietary strategy to manage blood lipids. The trial was registered at ClinicalTrials.gov as {"type":"clinical-trial","attrs":{"text":"NCT03429920","term_id":"NCT03429920"}}NCT03429920.     

Pharmacokinetics and Pharmacodynamics of (+)-Primaquine and (?)-Primaquine Enantiomers in Rhesus Macaques (Macaca mulatta)

Primaquine (PQ) remains the sole available drug to prevent relapse of Plasmodium vivax malaria more than 60 years after licensure. While this drug was administered as a racemic mixture, prior studies suggested a pharmacodynamic advantage based on differential antirelapse activity and/or toxicities of its enantiomers. Oral primaquine enantiomers prepared using a novel, easily scalable method were given for 7 days to healthy rhesus macaques in a dose-rising fashion to evaluate their effects on the blood, liver, and kidneys. The enantiomers were then administered to Plasmodium cynomolgi-infected rhesus macaques at doses of 1.3 and 0.6 mg/kg of body weight/day in combination with chloroquine. The (−)-PQ enantiomer had higher clearance and apparent volume of distribution than did (+)-PQ and was more extensively converted to the carboxy metabolite. There is evidence for differential oxidative stress with a concentration-dependent rise in methemoglobin (MetHgb) with increasing doses of (+)-PQ greater than that seen for (−)-PQ. There was a marked, reversible hepatotoxicity in 2 of 3 animals dosed with (−)-PQ at 4.5 mg/kg. (−)-PQ in combination with chloroquine was successful in preventing P. cynomolgi disease relapse at doses of 0.6 and 1.3 mg/kg/day, while 1 of 2 animals receiving (+)-PQ at 0.6 mg/kg/day relapsed. While (−)-PQ was also associated with hepatotoxicity at higher doses as seen previously, this has not been identified as a clinical concern in humans during >60 years of use. Limited evidence for increased MetHgb generation with the (+) form in the rhesus macaque model suggests that it may be possible to improve the therapeutic window for hematologic toxicity in the clinic by separating primaquine into its enantiomers.     

Complex interaction of hemoglobin (Hb) Nakhon Ratchasima [α63(E12)Ala→Val], a novel α2-globin chain variant with Hb E [β26(B8)Glu→Lys] and a deletional α(+)-thalassemia

Objectives: To describe the hematological and molecular features as well as diagnostic aspects of a complex hemoglobinopathy caused by interaction of a novel α2‐globin chain variant with hemoglobin (Hb) E and α⁺‐thalassemia. Methods: Blood specimen of a 41‐yr‐old Thai man was transferred to our center for the analysis of unknown Hb variant. Hb analysis was carried out using automated high‐performance liquid chromatography (HPLC) and capillary electrophoresis system. Mutation was identified by PCR and related techniques. Results: RBC analysis revealed a mild anemia but blood indices were within normal ranges. Hb‐HPLC analysis demonstrated, in addition to the Hb E and Hb A, two abnormal peaks not fully separated from Hb A and Hb E, but capillary electrophoresis showed a pattern of Hb E heterozygote with 4.0% Hb A₂. DNA analysis of the α2 globin gene identified a novel mutation (namely Hb Nakhon Ratchasima), GCC (Ala)→GTC (Val) at codon 63 in trans to the α⁺‐thalassemia (3.7‐kb deletion). Association of this novel α‐chain variant with β^E globin chain leads to the formation of another novel Hb derivative with different HPLC characteristics. Conclusion: Although Hb Nakhon Ratchasima might be clinically innocuous, differential diagnosis from other clinically relevant hemoglobinopathies is essential in routine setting. This could be made by using a simple PCR–restriction fragment length polymorphism assay or allele‐specific PCR assay developed in this study.     

Adherence to antiretroviral therapy,stigma and behavioral risk factors in HIV-infected adolescents in Asia

We studied behavioral risks among HIV-infected and uninfected adolescents using an audio computer-assisted self-interview. A prospective cohort study was initiated between 2013 and 2014 in Malaysia, Thailand, and Vietnam. HIV-infected adolescents were matched to uninfected adolescents (4:1) by sex and age group (12–14 and 15–18 years). We enrolled 250 HIV-infected (48% male; median age 14.5 years; 93% perinatally infected) and 59 uninfected (51% male; median age 14.1 years) adolescents. At enrollment, HIV-infected adolescents were on antiretroviral therapy (ART) for a median (IQR) of 7.5 (4.7–10.2) years, and 14% had HIV-RNA >1000?copies/mL; 19% reported adherence <80%. Eighty-four (34%) HIV-infected and 26 (44%) uninfected adolescents reported having ever smoked cigarettes or drunk alcohol (p?=?0.13); 10% of HIV-infected and 17% of uninfected adolescents reported having initiated sexual activity; 6 of the HIV-infected adolescents had HIV-RNA >1000?copies/mL. Risk behaviors were common among adolescents, with few differences between those with and without HIV.     

Guava Fruit and Acacia pennata Vegetable Intake Association with Frailty of Older Adults in Northern Thailand

As Thailand moves toward an aging society, frailty has become a concern amongst northern Thai elderly. The causes of frailty are multifactorial and include genetic, environmental, and socio-economic factors; diet is of particular interest. A cross-sectional study was conducted from September to October 2017 to investigate what kind of diets normally consumed by 350 Thai elders were associated with frailty using a questionnaire and frailty determination by Fried’s phenotype followed by phytochemical analyses of the diets. The multivariable logistic regression analysis demonstrated a significant positive association between certain foods and lower frailty. Guava fruit and Acacia pennata vegetable consumption had lower odds of frailty, which were 0.52 times (95% CI 0.28–0.96, p = 0.037) and 0.42 times (95% CI 0.21–0.83, p = 0.012) when adjusted for the potential confounders. The phytochemical analyses of guava fruit showed a significantly higher amount of total flavonoids (p < 0.001), total phenolic compounds (p = 0.002), and antioxidant capacity, including DPPH (p < 0.001), ABTS (p < 0.001), and FRAP (p = 0.002) when compared to those of banana. Acacia pennata vegetable contained a significantly higher amount of total phenolic compounds (p = 0.012) when compared to those of lettuce. These findings may assist in health promotion programs of frailty prevention by encouraging an increase in consumption of either guava fruit or Acacia pennata vegetable among Thai elderly.