Yo jyo hen shi ko, a novel Chinese herbal, prevents nonalcoholic steatohepatitis in ob/ob mice fed a high fat or methionine-choline-deficient diet.

BACKGROUND: Oxidative stress plays a role in the pathogenesis of nonalcoholic steatohepatitis (NASH). Yo jyo hen shi ko (YHK) is a complex compound purported to reduce reactive oxygen species (ROS) by blocking the propagation of radical-induced reactions. The aim of this study was to evaluate the role of the effect of YHK in experimental NASH. METHODS: NASH was induced in male ob/ob mice by a high-fat (HF) diet or methionine/choline-deficient (MCD) diet for 4 weeks. YHK-treated animals received YHK solution orally (20 mg/kg/day) in both experimental diets (n=6; each group) while control animals received only vehicle. RESULTS: The MCD and HF groups developed moderate diffuse macrosteatosis, hepatocellular ballooning, and a diffuse inflammatory infiltrate. With the addition of YHK, there was a marked reduction in macrosteatosis in both groups. This was associated with decreased lipoperoxide and reduced glutathione-GSH concentrations as well as reduced serum aminotransferases and improved histological markers of inflammation. These changes were also associated with weight loss in the MCD+YHK group and diminished weight gain in the HF+YHK group. CONCLUSION: YHK therapy blunts the development of macrosteatosis in these models of NASH and significantly reduces markers of oxidative stress. YHK also diminishes weight gain in this obesity prone model. Our findings warrant further study on the mechanisms involved with these effects.     

The patterns of use and factors associated with the patient admission of hospital emergencies for asthma and chronic obstructive pulmonary disease

The aim of this study was to describe the epidemiological characteristics of emergencies caused by asthma and chronic obstructive pulmonary disease (COPD) at the Hospital Clínico Universitario of Valencia (Spain) and to analyze factors related to hospital admissions for the same causes. Emergency room medical records for 1993 to 1995 of patients older than 14 years of age were examined to identify those due to asthma or COPD, according to established protocol. Demographic variables were described, followed by Poisson regression analysis of time and seasonal factors affecting emergencies. Factors related to hospital admission were analyzed by logistic regression, taking into account age group, sex, place of residence, and the year, month, day and hour of emergency room arrival. Asthma patients amounted to 1% of emergencies, while COPD patients accounted for 2%. The admission rate for women with asthma was higher than for men (F/M ratio = 0.78), whereas the rate for men with COPD was higher than for women (F/M ratio = 3.14). The largest age groups with asthma emergencies included young people aged 15 to 24 years old and those over 60. Hospital admissions or transfers to other hospitals were ordered for 17.4% of asthma patients and 38.8% of COPD patients. Nearly a third of COPD patients and a fifth of asthma patients were readmitted within the ten days following the first emergency. Clear temporal patterns of COPD emergency were observed for month (most occurring in winter), day of the week (most on Monday) and hour of the day (most during daytime hours, with fewer at midday). The time patterns were less evident for asthma emergencies, although the likelihood of admission because of asthma varied by month and day of the week. Emergency room records may be useful for studying the patterns of respiratory disease presentation. Other possible uses are epidemiologic monitoring and evaluation of health care quality.     

Switch from ritonavir-boosted to unboosted atazanavir guided by therapeutic drug monitoring

Plasma concentration of atazanavir (ATV) may be reduced when coadministered with tenofovir (TDF) or proton pump inhibitors. Boosting ATV exposure with ritonavir (r) may make it possible to overcome these drug interactions. However, jaundice and loss of the metabolic advantages of ATV are more frequent using ATV/r than ATV alone. Herein, we assessed whether therapeutic drug monitoring (TDM) could make it possible to identify the subset of patients in whom removal of ritonavir could be attempted without risk of suboptimal plasma ATV exposure and subsequent virological failure. A total of 56 patients with undetectable plasma HIV-RNA under a stable triple regimen containing ATV 300/100 mg qd were switched to ATV 400 mg qd. Plasma ATV concentrations were measured using a reliable high-performance liquid chromatography method. Median plasma ATV C(min) fell from 880 to 283 ng/ml (p = 0.03) after removal of ritonavir. While all patients on ATV/r showed ATV plasma concentrations within therapeutic values (IC(min) above 150 ng/ml) before switching, four patients (7%) fell below this threshold after switching to ATV 400 mg qd. However, only one of this group experienced virological failure at week 24 of follow-up. TDF was part of the antiretroviral regimen in all four cases. From a total of 29 (52%) patients on ATV/r showing grade 3-4 hyperbilirubinemia, only 7 (12%) remained on it upon switching to ATV 400 mg qd (p < 0.001). Patients with complete viral suppression under ATV/r 300/100 mg qd may benefit from switching to ATV 400 mg qd guided by TDM, which may make it possible to minimize adverse events without compromising antiviral efficacy in most cases.     

Advances in treating drug-resistant hepatitis B virus in HIV-infected patients

Introduction: Treatment of HIV infection with nucleos(t)ide analogs active against hepatitis B virus (HBV) highly improves hepatic outcomes in HIV-HBV coinfected patients, especially when tenofovir (TDF) is part of the antiviral regimen. Drug resistance has been the major drawback and must remain as the most important caveat when planning to treat dually or HIV and HBV independently in coinfected patients.

Areas covered: The use of lamivudine (LAM) as the only active anti-HBV agent should strongly be discouraged in HIV-HBV coinfected patients, although it might be considered for individuals with low serum HBV-DNA and in the absence of liver cirrhosis as an exception. In any other case drug resistance may cause any clinical benefit of this antiviral HBV therapy to disappear, and lead to cross-resistance with other antivirals and even occasionally select for HBV vaccine escape mutants. In cirrhotics, liver enzyme flares may be accompanied by life-threatening decompensation. Entecavir is generally not recommended as an anti-HBV agent in HIV-HBV coinfected patients given its low residual antiretroviral activity and potential for selection of resistance mutations in HIV. Adefovir is not active against HIV using HBV dosing and is no longer recommended as HBV therapy given its limited antiviral effect. Finally, telbivudine is not active against HIV, it is less potent than TDF against HBV and depicts low barrier to resistance and cross-resistance to LAM or emtricitabine.

Expert Opinion: The introduction of TDF has drastically reduced the clinical relevance of hepatitis B drug resistance in HIV-HBV coinfected individuals. The use of LAM as the only active anti-HBV agent should strongly be discouraged in this population.