Occult hepatitis B in blood donors in Indonesia: altered antigenicity of the hepatitis B virus surface protein

Background and aims  

Occult hepatitis B virus infection (OBI) poses a challenge to the safety of blood donation. The prevalence of OBI is not well documented in Indonesia, although this information in such an endemic country is needed. This study was aimed to evaluate the prevalence of occult hepatitis B in blood donors from two cities of Indonesia, and to study the genetic variation and its effect on the predicted antigenicity of HBsAg.     

Pregnancy outcome of patients with known celiac disease

OBJECTIVE: Celiac disease is a permanent intolerance to gluten, probably induced by an autoimmune mechanism. Controversy exists regarding the association between celiac disease and infertility, abortions, intra-uterine growth restriction (IUGR) and stillbirths. The present study was designed to investigate pregnancy outcome of patients with celiac disease. METHODS: A retrospective comparison between all pregnancies of women with and without known celiac disease, delivered during the years 1988-2002, was conducted. RESULTS: During the study period there were 48 deliveries of patients with celiac disease and 143,663 pregnancies of patients without known celiac disease. No statistically significant differences were noted between the groups regarding maternal or perinatal outcomes, including fertility treatments (0% among patients with known celiac versus 2.5% among patients without known celiac sprue; p=0.267), recurrent abortions (0 versus 5.2%; p=0.103), perinatal mortality (2.1 versus 1.4%; p=0.668). However, higher rates of labor induction (29.2 versus 11.9%; p<0.001) and IUGR (6.3 versus 2.1%; p=0.042) were found among patients with celiac disease as compared to patients without known celiac disease. CONCLUSION: The course of pregnancy of patients with celiac disease including perinatal outcomes is favorable. Since we found higher rates of IUGR, careful surveillance should be performed for early detection of IUGR. Further, prospective studies should focus on screening for celiac disease among patients presenting with IUGR of an unknown etiology.     

Computer-based identification of a novel LIMK1/2 inhibitor that synergizes with salirasib to destabilize the actin cytoskeleton

Neurofibromin regulates cell motility via three distinct GTPase pathways acting through two different domains, the Ras GTPase-activating protein-related domain (GRD) and the pre-GRD domain. First, the GRD domain inhibits Ras-dependent changes in cell motility through the mitogen activated protein cascade. Second, it also regulates Rho-dependent (Ras-independent) changes by activating LIM kinase 2 (LIMK2), an enzyme that phosphorylates and inactivates cofilin (an actin-depolymerizing factor). Third, the pre-GRD domain acts through the Rac1 GTPase, that activate the P21 activated kinase 1 (PAK1)-LIMK1-cofilin pathway. We employed molecular modeling to identify a novel inhibitor of LIMK1/2. The active sites of an ephrin-A receptor (EphA3) and LIMK2 showed marked similarity (60%). On testing a known inhibitor of EphA3, we found that it fits to the LIMK1/2-ATP binding site and to the latter's substrate-binding pockets. We identified a similar compound, T56-LIMKi, and found that it inhibits LIMK1/2 kinase activities. It blocked the phosphorylation of cofilin which led to actin severance and inhibition of tumor cell migration, tumor cell growth, and anchorage-independent colony formation in soft agar. Because modulation of LIMK by neurofibromin is not affected by the Ras inhibitor Salirasib, we examined the combined effect of Salirasib and T56-LIMKi each of which can affect cell motility by a distinct pathway. We found that their combined action on cell proliferation and stress-fiber formation in neurofibromin-deficient cells was synergistic. We suggest that this drug combination may be developed for treatment of neurofibromatosis and cancer.     

The impact of delayed blood centrifuging,choice of collection tube,and type of assay on 25-hydroxyvitamin D concentrations

Studies have examined the associations between cancers and circulating 25-hydroxyvitamin D [25(OH)D], but little is known about the impact of different laboratory practices on 25(OH)D concentrations. We examined the potential impact of delayed blood centrifuging, choice of collection tube, and type of assay on 25(OH)D concentrations. Blood samples from 20 healthy volunteers underwent alternative laboratory procedures: four centrifuging times (2, 24, 72, and 96 h after blood draw); three types of collection tubes (red top serum tube, two different plasma anticoagulant tubes containing heparin or EDTA); and two types of assays (DiaSorin radioimmunoassay [RIA] and chemiluminescence immunoassay [CLIA/LIAISON^®]). Log-transformed 25(OH)D concentrations were analyzed using the generalized estimating equations (GEE) linear regression models. We found no difference in 25(OH)D concentrations by centrifuging times or type of assay. There was some indication of a difference in 25(OH)D concentrations by tube type in CLIA/LIAISON^®-assayed samples, with concentrations in heparinized plasma (geometric mean, 16.1 ng ml^?1) higher than those in serum (geometric mean, 15.3 ng ml^?1) (p = 0.01), but the difference was significant only after substantial centrifuging delays (96 h). Our study suggests no necessity for requiring immediate processing of blood samples after collection or for the choice of a tube type or assay.