A C-Terminal Hydrophobic Region is Required for Homo-Oligomerization of the Hepatitis E Virus Capsid (ORF2) Protein

Hepatitis E virus (HEV) is the causative agent of hepatitis E, anacute form of viral hepatitis. The open reading frame 2 (ORF2) of HEV encodes the viral capsid protein, which can self-oligomerize into virus-like particles. To understand the domains within this protein important for capsid biogenesis, we have carried out in vitro analyses of association and folding patterns of wild type and mutant ORF2 proteins. When expressed in vitro or in transfected cells, the ORF2protein assembled as dimers, trimers and higher order forms. WhileN-terminal deletions up to 111 amino acids had no effect, the deletion of amino acids 585–610 led to reduced homo-oligomerization. This deletion also resulted in aberrant folding of the protein, as determined by its sensitivity to trypsin. This study suggests that a C-terminal hydrophobic region encompassing amino acids 585–610 of the ORF2 protein might be critical for capsid biogenesis.     

Augmentation of immune responses to hepatitis E virus ORF2 DNA vaccination by codelivery of cytokine genes

DNA vaccines encoding a viral structural protein have been shown to induce antiviral immune responses and provide protection against subsequent viral challenge. In the present study we show that DNA immunization with a plasmid expressing the hepatitis E virus ORF2 structural protein (pcDNA-ORF2) induced low levels of long-lasting antibody responses in the murine model. The use of plasmids expressing interleukin-2 (IL-2) and granulocyte-macrophage colony-stimulating-factor (GM-CSF) in conjunction with pcDNA-ORF2 enhanced the antibody responses generated by pORF-2. We further show that the immune responses generated by plasmid pcDNA-ORF2 can be boosted with virus-like particles composed of the ORF2 protein expressed through a baculovirus expression system.     

“Bouveret's syndrome” presenting with acute pancreatitis a very rare and challenging variant of gallstone ileus

INTRODUCTIONBouveret's syndrome is a rare variant of gallstone ileus and describes gastric outlet obstruction secondary to an impacted stone in the duodenum. Its presentation is vague and clinical diagnosis is often difficult resulting in a delay in diagnosis.PRESENTATION OF CASEWe report a patient who presented initially with non-specific symptoms and subsequently with features in keeping with acute pancreatitis, but eventually was found to have Bouveret's syndrome.DISCUSSIONDifferent treatment strategies are discussed. Although endoscopic treatment combined with many newer modalities like lithotripsy have been tried, surgery remains the definitive management in the vast majority of cases.CONCLUSIONBouveret's syndrome is a rare condition, can also present as pancreatitis and often difficult to diagnose initially, but with appropriate treatment has a good outcome.     

Determinants of successful medical education of caregivers of children with congenital heart diseases

Objective

To assess the implementation and efficiency of medical education among the caregivers of children with congenital heart disease (CHD) and to investigate its success factors.

α-tocopherol supplementation prevents lead acetate and hypoxia-induced hepatic dysfunction

Objective:Lead (Pb) is a long-known poison of environment and industrial origin. Its prolonged exposure affects cellular material and alters cellular genetics and produces oxidative damages. In this study, we investigated the exposure of chronic sustained hypoxia or lead acetate alone or in combination with or without supplementation of α-tocopherol on hepatic oxidative and nitrosative stress in rats.Results:Exposure of both lead and hypoxia showed decreased body weight, altered serum lipid profile, oxidant and enzymatic antioxidants status, serum HIF-1α and VEGF concentrations. Simultaneous α-tocopherol supplementation showed beneficial effects to all these alterations. Histopathological observations also showed hepatic degenerative changes after lead or hypoxia exposure either alone or in combination, but remarkable improvement has been noticed after α-tocopherol supplementation.Conclusion:Supplementation of α-tocopherol is beneficial to counter both lead acetate and hypoxia induced hepatic cytotoxicities possibly by reducing oxidative and nitrosative stress.KEY WORDS: α-tocopherol, hypoxia, lead acetate, nitrosative stress, oxidative stress     

TSH and Thyroid Hormones Both Regulate Bone Mass

Thyrotoxicosis is associated with a high-turnover osteoporosis, which has been solely attributed to elevated thyroid hormone levels. Mice lacking the thyroid hormone receptors α and β establish a role for thyroid hormones in regulating bone remodeling. We show that TSH, which falls when thyroid hormones rise, directly suppresses bone remodeling, and that TSH receptor null mice have profound bone loss. We suggest that reduced TSH signaling contributes to hyperthyroid osteoporosis and that TSH and its receptor could become valuable drug targets.     

Inhibition of hepatitis B virus DNA replicative intermediate forms by recombinant interferon-γ

AIM: To evaluate the in vitro anti-HBV activity of recombinant human IFN-γ, alone and in combination with lamivudine.METHODS: A recombinant baculovirus-HBV/HepG2 culture system was developed which could support productive HBV infection in vitro. Expression of HBsAg and HBeAg in infected HepG2 culture medium was detected by commercial enzyme immunoassays. HBV DNA replication intermediates were detected in infected cells by Southern hybridization and viral DNA load was determined by dot hybridization.RESULTS: IFN-γ at 0.1 to 5 μg/L efficiently down regulated HBsAg expression in transduced HepG2 cells.At 5 μg/L, IFN-γ also suppressed HBV DNA replication in these cells. While treatment with a combination of lamivudine and IFN-γ showed no additive effect,sequential treatment first with lamivudine and then IFN-γ was found to be promising. In this culture system the best HBV suppression was observed with a pulse of 2 μmol/L lamivudine for two days, followed by 1 μg/L IFN-γ for another four days. Compared to treatment with lamivudine alone, the sequential use of 0.2 μmol/L lamivudine for two days, followed by 5 μg/L IFN-γ for six days showed a 72% reduction in HBV cccDNA pool.CONCLUSION: This in vitro study warrants further evaluation of a combination of IFN-γ and lamivudine,especially in IFN-α non-responder chronic hepatitis B patients. A reduced duration of lamivudine treatment would also restrict the emergence of drug-resistant HBV mutants.     

Improving Trauma Care in India: the Potential Role of the Rural Trauma Team Development Course (RTTDC)

The Rural Trauma Team Development Course (RTTDC) was devised to optimize trauma resuscitation training in under-resourced rural institutions. This program appears ideal for India because of its dense traffic, large population, and high frequency of rural trauma. We report on the feasibility and desirability of introducing RTTDC in India. An instructor course for 20 faculties and a provider course for 23 were conducted in New Delhi, India. The courses were evaluated by multiple choice question (MCQ) performance, by rating the modules on a three-point scale (1 = very relevant, 2 = relevant, and 3 = not relevant) for communication skills, principles of performance improvement and patient safety (PIPS), and clinical scenarios. Evaluation questionnaires including desirability of promulgation in India were completed using a five-point Likert Scale (1 = strongly agree, 2 = agree, 3 = neutral, 4 = disagree, and 5 = strongly disagree). Overall written comments were also provided. Both faculty and providers improved post-course MCQ scores (p?<?0.05) with lower scores in the provider group. Seventy-eight percent faculty and 74 % providers rated the communication module very relevant. PIPS was rated very relevant by 72 % faculty and 65 % providers. There were over 150 comments, generally positive with over 90 % of both faculty and providers rating strongly agree to agree that the course be promulgated widely in India. The RTTDC including plans for promulgation was enthusiastically received in India, and its potential for improving trauma care including communication skills and PIPS appears excellent.     

Hydrophobic resin treatment of hydrothermal autohydrolysate for prebiotic applications

The production of a high-value xylooligosaccharide (XOS) prebiotic product from lignocellulosic autohydrolysate requires processing for the removal of non-carbohydrate components such as lignin and furfural. In this research, the nature of XOS dissolved in autohydrolysate is evaluated including the XOS degree of polymerization (DP) distribution and potential covalent association between XOS and lignin (LCC). The impact of these factors on the yield of XOS during treatment of Miscanthus autohydrolysate with hydrophobic resin is assessed. Over 30% of the XOS in autohydrolysate was found to be likely associated with lignin (“tied” XOS), all of which was removed during hydrophobic resin treatment along with over 90% of the dissolved lignin. However, loss of dissolved XOS during resin treatment was found to not be due solely to XOS association with lignin. Over 50% of the “free,” non-lignin-associated XOS was also removed by resin treatment. Interaction between “free” XOS and the hydrophobic resin was found to be highly dependent on DP with higher DP XOS being removed far more readily than low DP XOS. Over 80% of dissolved “free” XOS with a DP of six and above (X6+) was removed from autohydrolysate during treatment while only 17% of xylose (X1) was removed. Efforts to understand the interaction between the hydrophobic resin and XOS and to improve the recovery of XOS during hydrophobic resin treatment are presented.

∼30% of xylooligosaccharides (XOS) in autohydrolysate are likely bonded to lignin “tied,” contributing to loss during resin purification. Loss of “free” XOS depends on DP.     

Safety of transcatheter patent ductus arteriosus closure in small weight infants

Background: Patent ductus arteriosus (PDA) is a frequent congenital heart disease. Its transcatheter closure has become the treatment of choice in children and adults. However, the device closure of PDA in children with low weight is still challenging with high rate of complications. The aim of this study was to report further experience with trancatheter closure of PDA using the Amplatzer Duct Occluder(ADO) for children weighing less or equal to 8 kg. Methods: Twenty‐two patients (5 male, 17 female) underwent transcatheter closure of a PDA using ADO at a median age of 10 months (range 4 to 26) and a median weight of 7 kg (range 4.3 to 8). Follow‐up evaluations were performed with Doppler echocardiography at 24h, and at 6 and 12 months. Results: The device was implanted successfully in all patients. The median fluoroscopy time was 17.25 min (range 10 to 29). Within 24h, color Doppler revealed complete closure in 15 patients (68%), the other patients had a small residual shunt. No deaths were associated with the procedure. Two patients had a slight aortic protrusion of the device without coarctation and in one patient the device encroached partially on the left pulmonary artery without significant acceleration on Doppler echocardiography. All patients were discharged home the next day. All patients completed the 6‐month follow‐up with complete closure in 18 patients (81%). At the last evaluation in all patients at any time, there has been documentation of complete PDA closure in 20 (91%) of 22 patients. Conclusion: In patients weighing less or equal to 8 kg, percutaneous closure of PDA using an ADO is a safe and effective procedure. (J Interven Cardiol 2012;25:391–394)