Is transient elastography a useful tool for screening liver disease?

Transient elastography(TE)is a new non invasive tool for measuring liver stiffness,which is correlated to the histologic stage of liver fibrosis.Several studies in chronic liver disease(CLD)have determined a good accuracy of TE in predicting significant fibrosis and an optimal accuracy in predicting cirrhosis.Normal liver stiffness ranges between 3.3-7.8 KPa and using a cut off of 7.1 KPa,significant fibrosis and cirrhosis can be excluded with a very high negative predictive value(NPV).Positive predictive value(PPV)for the diagnosis of cirrhosis is lower using just a single scan but increases to 90% if high stiffness values are confirmed by a second independent scan.However the presence of fatty liver and metabolic syndrome slightly increases the readings and may reduce the accuracy of the test.It is uncertain if this increase is related to the presence of steatofibrosis or ifit is caused by steatosis itself.TE can be used in screening patients attending the liver clinics to identify those with signifi cant fi brosis or cirrhosis and may be particularly useful in discriminating HBV inactive carriers from chronic hepatitis B patients.TE,however,is not reliable in predicting the presence of esophageal varices in cirrhotics.Another potential indication for TE is the systematic screening of populations at high risk for CLD,such as intravenous drug users and alcoholics,but further studies are needed to determine its diagnostic accuracy in these settings.

Low-dose tenofovir is more potent than adefovir and is effective in controlling HBV viremia in chronic HBeAg-negative hepatitis B

AIM: To study the efficacy of tenofovir disoproxil fumarate (TDF) at low dose in a small open trial of chronic hepatitis B patients with advanced stage disease. METHODS: Eleven patients were treated with TDF 75 mg for a median period of 80 (range, 24-576) wk and then 7 cases were shifted to an adefovir 10 mg treatment group. All patients had been pre-treated with lamivudine: 5 had YMDD resistant mutants and 6 wild- type virus. When TDF was started, 4 patients had low- level viremia and 6 were PCR-negative. RESULTS: During TDF treatment, PCR remained negative in 10 patients, transaminase levels were normal and no significant viral breakthrough was observed. The drug was well tolerated in all cases. When TDF 75 mg was substituted with adefovir 10 mg, 3 out of 7 patients had a persistent viral rebound (2700-130 000 copies/mL), in whom lamivudine had to be reintroduced. CONCLUSION: Low-dose TDF monotherapy can control HBV viremia for an extended period of time without the emergence of resistance and is more potent than adefovir at the standard dosage. The use of a reduced dose of TDF could diminish the cost of therapy in low-income countries, but further studies in a larger population and in HBeAg-positive subjects are needed.

Alteration of the temporal association between courtship audio and visual components affects female sexual response

Some multimodal signals-that is,occurring in more than one sensory modality-appear to carry additional information which is not present when component signals are presented separately.To understand the function of male ring dove’s(Streptopelia risoria)multimodal courtship,we used audiovisual playback of male displays to investigate female response to stimuli differing in their audiovisual timing.From natural courtship recordings,we created a shifted stimulus where audio was shifted relative to video by afixed value and a jittered stimulus,where each call was moved randomly along the visual channel.We presented 3 groups of females with the same stimulus type,that is,control,shifted,and jittered,for 7 days.We recorded their behavior and assessed pre-and post-test blood estradiol concentration.We found that playback exposure increased estradiol levels,confirming that this technique can be efficiently used to study doves’sexual communication.Additionally,chasing behavior(indicating sexual stimulation)increased over experimental days only in the control condition,suggesting a role of multimodal timing on female response.This stresses the importance of signal configuration in multimodal communication,as additional information is likely to be contained in the temporal association between modalities.