Early Outcome of On-pump Versus Off-pump Elective Surgical Revascularization in Patients with Prior ST-Segment Elevation Myocardial Infarction

Coronary artery bypass graft surgery (CABG) is a proven treatment for coronary artery disease. History of a ST-elevation myocardial infarction (STEMI) is considered an independent risk factor for CABG irrespective of timing for an emergency or elective surgery. Patients with STEMI are candidates for both On-pump and Off-pump CABG procedures. This paper discusses the possible best option for elective surgical revascularization in patients with prior STEMI. This prospective clinical trial of 60 eligible patients with prior STEMI was conducted in a Tertiary Care Hospital from April 2018 to March 2019. Among them, 30 patients underwent off-pump (Group A) and 30 patients underwent on-pump (Group B) CABG procedures. Outcomes between both groups were observed from surgery to 1 month postoperatively. Data was analysed by the software statistical program for social science (SPSS 25.0 Inc). The surgery was successful in both groups of patients. Differences were observed by mean number of grafts per patient (2.77±0.43 vs. 3.10±0.71) and duration of operation (4.41±0.35 hours vs. 5.71±0.48 hours). An improvement in Left Ventricular Ejection Fraction (LVEF %) was observed in both groups postoperatively (17.98% vs. 10.98%) and the postoperative LVEF% at different time points were found statistically significant (p<0.05) over preoperative LVEF%. Multivariable stepwise logistic regression analysis correlated on-pump CABG with prolonged need for ionotropic support, need for blood transfusion, longer hospital stay and less improvement in LVEF%. The study supports the Off-pump CABG as a better surgical option over on-pump CABG in patients with prior STEMI.

Relationship of Conduction Defects and In-Hospital Outcome after Acute ST Segment Elevation Myocardial Infarction

The presence of conduction defects complicating acute myocardial infarction (MI) is relatively frequent and is associated with increased short and long term mortality. Thrombolytic therapy has been established to reduce the mortality in acute MI, however its role in reducing the incidence of conduction defects is less clearly defined. Morbidity and mortality associated with conduction defects also remain unchanged. This study was aimed to assess the correlation between conduction defects and adverse in-hospital outcome of patients with acute ST segment elevation MI. This cross sectional descriptive type of observational study was conducted among 100 purposively selected patients with acute ST segment elevation MI in the coronary care unit (CCU) of Mymensingh Medical College Hospital, Bangladesh from June 2012 to March 2013. The patients were divided into two groups depending on the presence or absence of conduction defects namely Group A- 40 patients with conduction defects and Group B- 60 patients without conduction defects. Highest number of the patients (36.0%) was in the age group of 45-55 years. In case of inferior MI, age groups 45-55 years and 55-65 years had equal number of patients (30.4%). Only 2.0% patients were in age group of 75-85 years and this group had only inferior MI. Total number of female patients were 16(16.0%). Female patients had more inferior MI (17.4%) than anterior MI (15.9%). Number of MI patients was slightly more in inferior MI (46.0%) than anterior MI (44.0%). Group B had equal number of patients in both anterior and inferior MI. Conduction defects were more common in inferior MI (43.5%) than anterior MI (40.9%). Atrio-ventricular conduction defects were more common in inferior MI whereas intra-ventricular conduction defects were more common in anterior MI. Complete heart block (CHB) was more prevalent in inferior MI. Complications were more common in Group A (65.0%) than Group B (18.3%). In terms of complications the difference between two groups were significant (p<0.001). Group A showed higher rate of mortality (20.0%) than Group B (3.3%). In cases of anterior MI difference in mortality between Group A and Group B was highly significant (p<0.001). Conduction defects in the setting of acute MI are a common finding. Atrio-ventricular conduction defects occur more frequently in inferior MI whereas intra-ventricular conduction defects were more frequently encountered in anterior MI. Patients with conduction defects had more complications than those without conduction defects. Presence of conduction defects significantly increases the mortality of patients with anterior MI.

Association of Aortic Valve Sclerosis with Angiographic Severity of Coronary Artery Disease in Patients with Acute Coronary Syndrome, Aged ≤65 Years

Aortic valve sclerosis (AVS) represents a degenerative process that progresses with advancing age. The study was intended to find out the association between aortic valve sclerosis and the severity of CAD in patient's age ≤65 years with acute coronary syndrome. This cross-sectional analytical study was carried out in the department of cardiology, National Institute of Cardiovascular Diseases (NICVD), Dhaka, Bangladesh during a period of October 2017 to September 2018. A total of 140 Acute coronary syndrome (ACS) patients undergoing coronary angiogram during index hospitalization were included in the study. Study patients were divided into two groups on the basis of echocardiographic presence or absence of Aortic valve sclerosis (AVS), with 70 patients in each group. Group I was patients with aortic valve sclerosis and Group II was patients without aortic valve sclerosis. All patients underwent transthoracic echocardiography before they underwent coronary angiography on different days. Severity of CAD was determined by Gensini score and Vessel score. Association of traditional risk factors (smoking habit, hypertension, diabetes mellitus, dyslipidaemia and family history of CAD) with severity of CAD was investigated. Coronary angiography showed that AVS group had a higher positive rate of CAD (82.9% vs. 54.3%, p<0.001) and incidence rate of triple vessel CAD (40% vs. 14.3%, p<0.001) than non-AVS group. Gensini score had higher in AVS group than non AVS group (37.9±27.8 vs. 12.5±14.2; p<0.001). Multivariate analysis showed that AVS (p=0.01) and age (p=0.04) were independent predictors of the presence of significant coronary artery disease. The study concluded that echocardiographically detected AVS is an independent predictor of coronary artery disease severity. There is positive correlation between severity of AVS and severity of CAD in patient's age ≤65 years with ACS.

Association of Diastolic Dysfunction with Angiographic Severity of Coronary Artery Disease in patients with Non-ST Elevation Myocardial Infarction

In recent years, diastolic dysfunction is an evolving context. Presence of left ventricular diastolic dysfunction (LVDD) indicates a poor prognosis in patients with an ACS and chronic coronary artery diseases. This study evaluated the association of LVDD and angiographic severity of CAD in patients with non-ST elevation myocardial infarction (NSTEMI). This cross-sectional analytical study was carried out in National Institute of Cardiovascular Diseases, Dhaka, Bangladesh, during the period of April 2017 to March 2018. A total of 120 NSTEMI patients undergoing coronary angiogram (CAG) during index hospitalization were included in the study. All patients underwent transthoracic echocardiography before they underwent CAG on different days. Presence (Group I, n=65) and absence of LVDD (Group II, n=55) was established by echocardiography. Severity of CAD was assessed by Vessel score and Leaman score. Association of traditional risk factors (smoking habit, hypertension, diabetes mellitus, dyslipidemia and family history of CAD) with severity of CAD was investigated. Vessel score showed coronary artery obstruction (CAO) was present in 62(95.4%) patients in Group I and 35(63.6%) patients in Group II, single vessel was involved in 17(27.4%) patients while multi vessel in 45(72.6%) patients was found in Group I. On the contrary 27(77.1%) single vessel patients and 8(22.9%) multi vessel patients were found in Group II. Positive Leaman score was significantly higher in Group I, 62(95.4%) than that of Group II, 35(63.6%) which is statistically significant (p<0.001). This study showed a positive correlation between LVDD and CAD severity in terms of vessel score and Leamanscore. This study also demonstrates that the severity of vessel score and Leaman score was higher in the higher grade of diastolic dysfunction. The present study concludes that LVDD is associated with angiographically severe CAD in patients with NSTEMI.

Prevalence rate of attention deficit hyperactivity disorder (ADHD) and computer vision syndrome (CVS) symptoms predisposition among digital device users of Bangladesh

Background

Around 5.29% of the world population is suffering from ADHD, and 60 million people are suffering from CVS, with an increasing rate of prevalence of these disorders. This study aimed to determine the prevalence rate of ADHD and CVS symptoms among the Bangladeshi population.

Results

To assess the aim of the study, a cross-sectional survey was conducted online through stratified sampling, and 197 responses were collected from the participants. Our survey method follows these criteria where the ARSV1.1 standard questionnaire was followed for the ADHD questionnaire, and a self-administered questionnaire was established based on the symptoms of CVS. The male age ranges from 18–24 have the highest value of ADHD (34%) coincided with > 6 h digital device usage (51%), and the Stroop effect is significantly correlated with the ADHD score (0.498, p < 0.01). The Stroop effect value is also higher among the males aged 18–24, digital device users for > 6 h (48%).

Conclusions

With the advent of science, it is impossible to avoid digital devices as necessary. Notwithstanding, safe and appropriate use of digital media is a must for healthy living.

Association of Echocardiographic Epicardial Fat Thickness with the Angiographic Severity of Coronary Artery Disease in Patients with Acute Coronary Syndrome

Estimation of visceral adipose tissue is important as it carries high cardiometabolic risk and several methods are available as its surrogate. Epicardial fat thickness (EFT) is a direct measure of visceral fat rather than anthropometric measurements. EFT can be accurately measured by two-dimensional (2D) echocardiography. It tends to be higher in patients with Acute Coronary Syndrome (ACS). The present study was intended to find out the association between echocardiographic EFT and severity of Coronary Artery Disease (CAD) in patients with ACS. This cross-sectional observational study was carried out in the department of cardiology, National Institute of Cardiovascular Diseases, Dhaka, Bangladesh from October 2017 to September 2018. Sampling technique was purposive sampling. Comparison between groups was done by unpaired-t test & dichotomous variables were compared by chi-square test. A total of 164 patients was enrolled in the study, prospectively examined EFT on echocardiography and patients were divided into 2 groups, Group I patients with EFT >4.65mm and Group II patients with EFT ≤4.65mm. Coronary angiograms were analyzed for the extent and severity of CAD using Gensini score. The mean EFT (mm) was found 6.1±1.0 in Group I and 3.5±0.7 in Group II (p<0.001). Patients with a higher EFT were associated with a high Gensini score (Group I vs. Group II, 50.3±24.1 vs. 21.9±20.0; p<0.001). Multivariate analysis showed that EFT (OR 6.07, p<0.001) and smoking (OR 2.66, p=0.03) were independent factors affecting significant coronary artery stenosis. By ROC curve analysis, EFT >4.65mm predicated the presence of significant coronary stenosis by 76.1% sensitivity and 69.9% specificity. EFT measured using Transthoracic echocardiography (TTE) significantly correlates with the severity of CAD. It is sensitive, easily available, and cost-effective and assists in the risk stratification and may be an additional marker on classical risk factors for CAD.

Antidiabetic Activity of Momordica charantia L. and Mechanism of Insulin Secretion of 1-Butanol Soluble Part on Type 2 Diabetic Model Rats

The in vivo effects of fruit pulp juice (MC-PJ) of Momordica charantia and its 1-butanol soluble part (MC-BP) and aqueous soluble part (MC-AP) on blood glucose of type 2 diabetic rats were studied. In vitro insulin secretion in response to MC-BP and MC-AP from whole perfused pancreas was measured. For elucidating the mechanism of insulinotropic action, the insulin secretory activity of MC-BP in the presence of 11 mM glucose, 50 μM verapamil (Ca++ channel blocker), 8 mM diazoxide (K+ ATP channel opener) and 10 mM theophylline (cAMP phosphodiesterase inhibitor) were studied. Serum glucose was measured by glucose oxidase-peroxidase method and rat insulin was assayed by specific ELISA. In the in vivo study, MC-BP significantly opposed the rise of serum glucose compared to control at 105 min (p<0.05). Although the MC-AP and MC-PJ lowered the serum glucose both at 60 and 105 min, these were not statistically significant. In the in vitro study, only MC-BP produced 22-fold increase in insulin secretion from the perfused pancreas at nonstimulatory glucose level, which was significant (basal vs. MC-BP, 0.071±0.009 vs. 1.563±0.150 ng/ml, p<0.001). The MC-BP also enhanced the insulin secretion from the glucose-stimulated pancreas (p<0.001). The MC-BP induced insulin secretion was not affected in presence of diazoxide and verapamil. The obtained results also showed that MC-BP enhanced the insulin secretory effect of theophylline (p<0.001). The findings indicate that MC-BP has stimulatory effects on physiological pathways of insulin secretion which may underlie its reported antidiabetic action. Dhaka Univ. J. Pharm. Sci. 19(2): 111-117, 2020 (December)

Prevalence and types of genetic polymorphisms of CYP2C19 and their effects on platelet aggregation inhibition by clopidogrel

OBJECTIVE

The current study was conducted to determine the distribution of genetic polymorphisms in CYP2C19 in Iraqi patients and their role in inter-individual variability of clopidogrel efficacy.

PATIENTS AND METHODS

A prospective controlled study was done on 100 patients under high risk of cardiovascular diseases who started clopidogrel prophylactic therapy. Polymerase chain reaction-restriction fragment length polymorphism method was used to determine the existence of the CYP2C19 gene mutation. Vasodilator-stimulated phosphoprotein (VASP) index baseline besides one-month post-therapy was analyzed by dual-color flow cytometry analysis.

RESULTS

Eight gene mutations of CYP2C19 were found (*1/*1), (*1/*2), (*1/*3), (*1/*8), (*1/*17), (*2/*2), (*2/*4), and (*3/*3) with higher prevalent CYP2C19*1 gene. Homozygous CYP2C19*1 allele was shown to be the rapid metabolizer comparing to the heterozygous CYP2C19*1 allele, whereas, CYP2C19*2 and CYP2C19*3 were resistant alleles and were present in 28% of patients. The analysis of VASP phosphorylation produces accurate inter-individual response variability in platelets inhibition by antiplatelet drugs.

CONCLUSIONS

In vitro gene analysis and VASP index improve the clinical outcome of a patient candidate to clopidogrel as prophylaxis in cardiovascular events.

Study on Precipitating Factor of Chronic Hepatic Encephalopathy

Hepatic encephalopathy (HE) is a neuro-psychiatric manifestation of chronic liver disease causing significant morbidity and mortality worldwide. Though the exact mechanism is unknown but it is well accepted that various precipitating factors are involved in hepatic encephalopathy. Aim of the study was explore the precipitating factors of chronic hepatic encephalopathy. This cross sectional descriptive study was conducted in the Department of Medicine and Department of Hepatology, Mymensingh Medical College Hospital, Mymensingh, Bangladesh during the period from April 2016 to October 2016. One hundred patients with hepatic encephalopathy fulfilling the inclusion and exclusion criteria were enrolled. Inclusion criteria were designed for all diagnosed cases of hepatic encephalopathy associated with cirrhosis of liver aged 18 years or above irrespective of sex. Patients with acute fulminant hepatitis and non-cirrhotic hepatic encephalopathy were excluded. The result of the study was mean age of hepatic encephalopathy was 52.81±8.15 years and 94.0% patients were above 40 years. Male (66.0%) were predominant over female (34.0%). HBsAg and Anti HCV were positive in 49.0% and 11.0% patients respectively. Stage of hepatic encephalopathy was stage-I in 8.0%, stage-II in 37.0%, stage-III in 39.0% and stage-IV in 16.0% patients. Changes of biochemical parameters were low haemoglobin level (70.0%), raised total count of leukocyte (25.0%), low platelet count (68.0%), low serum albumin (98.0%) raised prothrombin time (60.0%), low serum sodium (34.0%) and low serum potassium (63.0%). The recoded precipitating factors were gastrointestinal bleeding (14.0%), constipation (37.0%), hyponatremia (34.0%), hypokalemia (28.0%) infections (20.0%), use of diruretics (8.0%), use of sedatives (4.0%) and excess intake of protein (6.0%). While precipitating factor was absent in 11.0% of cases. In conclusion there are different factors which play a key role in precipitating hepatic encephalopathy but electrolytes imbalance, constipation, infections, Upper GI bleed, diuretics are the most common precipitating factors.

Demography and Symptom Profile of Tetanus: A Cross-sectional Observation in an Infectious Disease Hospital of Bangladesh

Tetanus is a potentially preventable neurological infectious disorder with paucity of literature in Bangladesh. We aimed to see the demography and symptom profile of tetanus cases managed at the Infectious disease Hospital Sylhet. This hospital based cross-sectional descriptive study was conducted within the time period of January to December 2012 among 50 consecutive admitted patients in the Infectious Disease Hospital, Sylhet, Bangladesh who were diagnosed as a case of tetanus and fulfilling the inclusion criteria and exclusion criteria. Neonatal tetanus was considered as exclusion criteria and clinical diagnosis of tetanus was considered as the tetanus. Data were collected purposively with pretested predesigned questionnaire. Data were processed manually and analyzed with the help of SPSS Version 16.0. The mean±SD age was 33.00±16.8 years, ranging from 10 to 70 years. Among the 50 respondents, 72.0% were male, 50% from lower class, 34% were students and 30.0% had their educational status of primary level, 60.0% from rural social background. Trismus was found in 98.0% of the cases, rigidity in 96.0% cases, body ache in 94.0% cases, dysphagia in 92.0% cases, neck pain in 78.0% cases, dysarthria in 92.0% cases, reflex spasm in 66.0% cases, opisthotonus in 46.0% cases and urinary retention in 26.0% cases. In this study rural male people with lower socioeconomic status individuals were mostly affected with trismus, rigidity, body ache and dysphagia symptoms.

Gender Difference of Common Risk Factors and in Hospital Outcome of Acute Ischaemic Stroke

This was an observational study with cross-sectional comparison of risk factors between sexes in the distribution of common risk factors and in hospital outcome of acute ischaemic stroke with the purpose of developing optimal strategies for the prevention and care of this disease. This study was conducted in the Department of Medicine and Department of Neurology, Sylhet MAG Osmani Medical College Hospital, Sylhet, Bangladesh from March 2013 to August 2013. Patients were divided in Group A- male patients with acute ischaemic stroke (n=47) and Group B- female patients with acute ischaemic stroke (n=47), were included according to inclusion and exclusion criteria. Male were more frequently diabetic [19(40.4%) vs. 10(21.3%), p=0.044] and smoker [41(87.2%) vs. 18 (38.3%); p<0.001] than that of female. Female were older [67.4±8.9 years vs. 62.2±8.1 years; p<0.05]; more frequent hypertensive [36(76.6%) vs. 26(55.3%); p=0.030] than that of male but no gender differences in atrial fibrillation, ischemic heart disease, dyslipidaemia. In-hospital functional outcome (p=0.039) was significantly better in male than that of female patients with acute ischaemic stroke. Characterization of risk factors for acute ischaemic stroke in both sexes may aid in developing prevention strategies to reduce stroke incidence.

Abstract P2-01-10: Withdrawn

This abstract was withdrawn by the authors.

Citation Format: Hasan MK, Widhopf II GF, Zhang S, Shen Z, Briggs SP, Kipps TJ. Withdrawn [abstract]. In: Proceedings of the 2018 San Antonio Breast Cancer Symposium; 2018 Dec 4-8; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2019;79(4 Suppl):Abstract nr P2-01-10.

Anterior Mediastinal Teratoma- A Rare Variety

Anterior mediastinal teratomas are rare germ cell tumors. We report a case of such rare tumor in a 16 years old boy who presented with sudden severe right sided abdominal pain which radiating to chest for one day. CT scan of the chest was suggestive of anterior mediastinal teratoma. Patient underwent Clamshell thoracotomy. Peroperatively a large mass was found in the anterior mediastinum containing huge amount of sebum like material. It was adherent to mediastinal surface of right & left lung, pericardium and great vessels (SVC, Aorta). The tumor and was resected out except part of its posterior surface which was adherent to pericardium and great vessels and was left in situ. He had a smooth & uneventful post-operative recovery. Histopathology reported as mature (benign) teratoma with no evidence of malignancy.Pulse Vol.10 January-December 2017 p.52-56

Surgical Management of Large Mediastinal Masses–12 Years’ Experience in Apollo Hospitals Dhaka

Objective: The aim of this study was to evaluate the role of surgical treatment for large mediastinal tumors. A retrospective study was done from 6.8.2005 to 11.5.2017. Total 39 patients were included in this study. Age range was from 7 months to 70 years. Male was 24 and female was 15.Background: Most of the tumours were thymoma (12 cases). Others were thymoma with myasthenia gravis in 3 cases, Thymic carcinoma 2 cases, Nodular sclerosing Hodgkin’s lymphoma in 1 case, Schwannoma in 3 cases, Cystic mass in 5 cases, Schwannoma with cystic degeneration in 1 case, Fibromyxoma in 1 case, Dermoid in 4 cases, Teratoma in 3 cases, Fibrosing mediastinitis in thymic mass in 1 case, Lymphoid hyperplasia in 1 case, Malignant Mesenchymal tumour in 1 case, Myxoid Liposarcoma in 1 case.Method: Surgical exposure varies from sternotomy in 22 cases, to clamshell incision in 1 case, posterolateral thoracotomy in 14 cases and anterolateral thoracotomy in 2 cases. Superior Venacava was injured in 1 case, repaired successfully by 6/0 prolene controlled by partial clamp. Some of the mediastinal mass needed careful dissection from lung, pleura, encircling distal aortic arch and proximal part of left subclavian artery, encircling left brachiocephalic vein. 1 case needed reconstruction of sternum with prolene mesh, marsupialization was done in 2 cases, adjacent pleura, fatty tissue, part of pericardium was removed in 5 cases. Lobectomy was needed in 1 case. In 1 case, recurrence of fibrosing mediastinitis needed steroid therapy. Extensive growth of the tumour which involved surrounding vital structures was decided not to proceed for excision in 2 cases.Results: Overall five-years survival rate was 94.87% .2 patients of the series died due to disease process as they were cases of advanced malignant mediastinal mass.Conclusion: Surgical treatment for mediastinal mass specially involving surrounding structures though challenging, gives good outcome.Pulse Vol.10 January-December 2017 p.12-17

Left Atrial Myxoma with Mild Left Ventricular Dysfunction— A Case Report

Atrial Myxoma is the most common primary cardiac tumors accounting for about 50% of benign primary cardiac tumors, with the majority located in the left atrium. This is a case of large left atrial (LA) myxoma presented with features of mitral stenosis associated with moderate left ventricular failure (LVF) and mild pulmonary artery hypertension (PAH) The patient improved markedly after tumor excision.Pulse Vol.10 January-December 2017 p.29-33

Socio-economic performance of Bt eggplant cultivation in Bangladesh

A study was conducted in 35 districts of Bangladesh during 2016-17 winter season for assessing the farm level performance of Bt eggplant in reducing pesticide use, cultivation cost and increase farm income. Five hundred five Bt eggplant farmers were selected purposively and 350 non-Bt eggplant farmers were selected randomly for the study. Net returns per hectare were Tk. 179,602/ha for Bt eggplant as compared to Tk. 29,841/ha for non-Bt eggplant. Pesticides were applied 11 times to Bt eggplant where as it was 41 times to non-Bt eggplant for controlling sucking pests. The Bt eggplant farmers saved 61 percent of the pesticide cost compared to non-Bt eggplant farmers, experienced no losses due to fruit and shoot borer, and received higher net returns. The experience with Bt eggplant technology was good for most of the locations and up to the mark and off course this technology will be significantly improved to their socio-economic conditions in future as reported by the Bt respondents. All Bt and 86% non-Bt farmers wanted to cultivate Bt eggplant in the next year if they can obtain the seeds/seedlings from the research station. For getting higher yield and economic benefits, in the course of technology dissemination, the importance of good production practices must be emphasized.Bangladesh J. Agril. Res. 43(2): 187-203, June 2018

Comparative Study between the Use of Multidose Standard Cardioplegia and Long Acting Del Nido Cardioplegia during Intracardiac Repair for Tetralogy of Fallot in Pediatric Patients

Pediatric myocardium is unique from mature myocardium; thus, the use of adult cardioplegia for pediatric cardiac operations may provide suboptimal myocardial protection. It is found that children undergoing heart surgery show evidence of less myocardial damage when del Nido cardioplegia is used instead of a standard cardioplegic solution. Del Nido cardioplegia solution provides a depolarized hyperkalaemic arrest lasting up to 60 minutes, reduces spontaneous and inducible activity during arrest, and prevents hyper contraction during early reperfusion. In this single blind randomized trial, a total of 60 patients underwent intra cardiac repair for TOF in National Institute of Cardiovascular Diseases, Dhaka, Bangladesh from July 2014 to January 2016 fulfilling inclusion and exclusion criteria. They were randomly assigned in two groups- 30 patients in Del Nido group (Group A) and 30 patients in standard group (Group B). Comparison between groups was done by Chi square test and Student's test. All data were analyzed by SPSS 20.0 for windows. P value less than 0.05 was considered as significant. There was statistically significant difference among the patients in terms of mean total initial cardioplegia volume, mean number of additional dose, mean additional dose amount, mean cross clamp time, mean CPB time (331.67±188.07 vs. 458.67±226.62, p=0.022; 0.13±0.35 vs. 1.27±0.89, p=0.000; 23.33±60.76 vs. 336.83±259.6, p=0.000; 45.10±10.35 vs. 59.23±23.21, p=0.003; 89.30±15.73 vs. 111.10±29.23, p=0.001 respectively). Mean post operative serum troponin I level at arrival in ICU and after 24 hours between two groups were statistically significantly different (55.60±32.91 vs. 83.5±58.99; p=0.024 and 13.01±5.84 vs. 18.16±9.51; p=0.014 respectively). The mean ventilation duration, mean ICU stay were also statistically significant. This study showed that cardiac arrest with Del Nido cardioplegia during intra cardiac repair for TOF was associated with improved myocardial protection over standard cardioplegia in terms of reduced CPB and cross clamp times, lower total volume of cardioplegia.

Abstract P1-01-05: Wnt5a induces ROR1 to associate with cortactin, which undergoes tyrosine phosphorylation, and enhances migration of breast cancer cells

Background: ROR1is an evolutionarily conserved, oncoembryonic surface-antigen expressed in breast cancer. Previously, we found that ROR1 can serve as a receptor for Wnt5a, which can induce non-canonical Wnt signaling that enhances cancer-cell migration. Recently we found that Wnt5a could induce ROR1 to complex with a cytoskeletal protein designated HS1, which recruited ARHGEF1, enhanced activation of RhoA, and promoted leukemia-cell migration. These effects of Wnt5a on CLL cells could be inhibited by cirmtuzumab, a humanized, high-affinity monoclonal antibody (mAb) specific for ROR1. As expression of HS1 is limited to hematopoietic cells we examined breast cancer cell lines and primary breast cancer cells for expression of cortactin. Cortactin (also called EMS1), is a cytoskeletal protein, which is homologous in structure and function to HS1 and is broadly expressed in human cancers, including breast cancer.

Methods: We performed immunoprecipitation studies using high-affinity mAb to ROR1 or cortactin and immunoblot analysis to examine for the association of ROR1 with cortactin and tyrosine phosphorylation of cortactin at Y421. We also assessed the expression levels of cortactin, ROR1, and ARHGEF1, in the MCF7 breast cancer cell line and in breast-cancer patient-derived xenografts (PDX). We also generated MCF7-ROR1 cells, which were stably transfected to express ROR1 or various mutant forms of ROR1 generated to study the structure-function requirements for effective ROR1-cortactin interactions.

Results: We found that ROR1 associates with cortactin in freshly-isolated breast cancer PDX tumors or in PDX cells cultured with exogenous Wnt5a. We corroborated these results in breast cancer cell line MCF7-ROR1 cells, which were transfected to express ROR1 and found to migrate more effectively than the parental MCF7 lacking expression of ROR1. Wnt5a also induced cortactin tyrosine phosphorylation at Y421, recruitment of ARHGEF1, and activation of RhoA, which we found associated with enhanced breast-cancer cell migation. The capacity of Wnt5a to induce such changes could be blocked by treatment of the cells with cirmtuzumab. We generated truncated forms of ROR1 without a proline-rich domain (PRD) and found PRD was necessary for this association or Wnt5a-induced cortactin phosphorylation and enhanced cancer-cell migration. Accordingly, we introduced single amino-acid substitutions of proline (P) to alanine (A) in the ROR1-PRD at positions 784, 808, 826, or 841 in potential SH3-binding motifs. In contrast to wild-type ROR1, or other ROR1P→A mutants, ROR1P(841)A had impaired capacity to recruit cortactin and ARHGEF1 to ROR1 in response to Wnt5a. Moreover, Wnt5a could not induce cells expressing ROR1P(841)A to phosphorylate cortactin or activate ARHGEF1, and was unable to enhance the motility of the MCF7 cells transfected with this mutant form of ROR1.

Conclusions: Collectively, these studies indicate the capacity of cortactin to complex with ROR1 plays an important role in ROR1-dependent Wnt5a-enhanced breast cancer cell migration. These studies also demonstrate that cirmtuzumab can inhibit the formation of cortactin-ROR1 complexes, cortactin phosphorylation, and cancer-cell migration, and metastasis.

Citation Format: Hasan MK, Tripple V, Widhopf II GF, Yu J, Zhang S, Parker BA, Kipps TJ. Wnt5a induces ROR1 to associate with cortactin, which undergoes tyrosine phosphorylation, and enhances migration of breast cancer cells [abstract]. In: Proceedings of the 2017 San Antonio Breast Cancer Symposium; 2017 Dec 5-9; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2018;78(4 Suppl):Abstract nr P1-01-05.

Non-invasively Measured Carotid Artery Intima-Medial Thickness May Be a More Useful Marker of Coronary Artery Disease in Diabetic than Non-Diabetic Patients

Carotid intima-medial thickness has long been proposed as a surrogate marker of atherosclerotic vascular disease in other vascular beds, most notably the coronary arteries with its practical implications. This observational study aimed at exploring the relationship of a hypothetical stronger relationship of carotid intima-medial thickness with coronary artery disease in diabetic patients than non-diabetic counterparts. Thirty diabetic patients and 74 non-diabetic patients who were referred for coronary angiogram in the Departments of Cardiology Bangabandhu Sheikh Mujib Medical University and Combined Military Hospital, Dhaka Cantonment, Bangladesh from January, 2002 and December, 2003 were studied. Carotid ultrasound was done to determine intima-medial thickness and coronary angiogram to detect coronary artery lesions. Background demographic data and cardiovascular risk factors were determined. Of the 30 diabetic patients 24 subjects had CAD. Twenty two of these 24 patients showed increased carotid IMT. None of the patients without CAD had shown carotid artery intima-medial thickening (sensitivity 91% specificity 100%). In contrast, in the non-diabetic group 44 patients out of 63 with CAD showed increased carotid artery IMT. Four of the 11 non-diabetic patients without CAD showed positive carotid ultrasound study results (sensitivity 70%, specificity 63%). This study showed a strong association of coronary artery disease with carotid intima-medial thickness in diabetic patients compared to non-diabetic subjects. This finding may be applicable for Bangladeshi diabetic population. This surrogate marker of coronary artery disease can be useful in the management of diabetes as regards their prevention of coronary artery disease. The practical and clinical implications of these findings might be the pioneer study in diabetic subjects and need to be further determined in a larger community level study.

Wnt5a induces ROR1 to associate with 14-3-3ζ for enhanced chemotaxis and proliferation of chronic lymphocytic leukemia cells

Wnt5a can activate Rho GTPases in chronic lymphocytic leukemia (CLL) cells by inducing the recruitment of ARHGEF2 to ROR1. Mass spectrometry on immune precipitates of Wnt5a-activated ROR1 identified 14-3-3ζ, which was confirmed by co-immunoprecipitation. The capacity of Wnt5a to induce ROR1 to complex with 14-3-3ζ could be blocked in CLL cells by treatment with cirmtuzumab, a humanized mAb targeting ROR1. Silencing 14-3-3ζ via small interfering RNA impaired the capacity of Wnt5a to: (1) induce recruitment of ARHGEF2 to ROR1, (2) enhance in vitro exchange activity of ARHGEF2 and (3) induce activation of RhoA and Rac1 in CLL cells. Furthermore, CRISPR/Cas9 deletion of 14-3-3ζ in ROR1-negative CLL cell-line MEC1, and in MEC1 cells transfected to express ROR1 (MEC1-ROR1), demonstrated that 14-3-3ζ was necessary for the growth/engraftment advantage of MEC1-ROR1 over MEC1 cells. We identified a binding motif (RSPS⁸⁵⁷SAS) in ROR1 for 14-3-3ζ. Site-directed mutagenesis of ROR1 demonstrated that serine-857 was required for the recruitment of 14-3-3ζ and ARHGEF2 to ROR1, and activation of RhoA and Rac1. Collectively, this study reveals that 14-3-3ζ plays a critical role in Wnt5a/ROR1 signaling, leading to enhanced CLL migration and proliferation.

Ventricular Septal Defect with Pulmonary Valve Endocarditis with Vegetation - Successful Surgical Treatment in Apollo Hospitals Dhaka

Background: Pulmonary valve vegetation with ventricular septal defect needs early surgical intervention.Case presentation: A 21 years old man got admitted in Apollo Hospitals Dhaka, with the complaints of dyspnoea on exertion since childhood. Echocardiogram revealed a large perimembranous ventricular septal defect, moderate pulmonary stenosis, vegetation attached with pulmonary valve leaflet moving during systole & diastole. During operation ventricular septal defect was closed by dacron patch. Large vegetation was excised from anterior cusp of pulmonary valve. A perforation in right cusp of pulmonary valve was repaired with pericardial patch. Transesophageal Echocardiogram revealed well functioning ventricles and no leakage through the repaired Ventricular Septal Defect and pericardial patch in pulmonary valve leaflet.Result: Culture Sensitivity from vegetation showed no growth and histopathological examination revealed tissue consistent with vegetation of Pulmonary Valve. Post- operative echocardiogram showed no residual shunt or vegetation. The patient was discharged on 8th post operative day in good general condition and is doing well till now.Conclusion: Pulmonary valve endocarditis with vegetation with ventricular septal defect is a rare association. Early surgical intervention gives good outcome.Pulse Vol.9 January-December 2016 p.69-72

A 42-year-old man with huge abdominal mass

Patients presenting with abdominal lump is a common clinical finding in our medical practice. Most of the cases can be diagnosed without much difficulty. But sometimes it can be difficult to diagnose the cause of the lump. Here we are presenting a 42-year-old man who visited his physician in Bangabandhu Sheikh Mujib Medical University with huge abdominal lump. Initially it was diagnosed as hepatocellular carcinoma (HCC). Later it turned out to be case of adrenocortical carcinoma (ACC). Problems related to diagnosis and management is also discussed.

A case of acute intermittent porphyria

Acute intermittent porphyria (AIP) is a rare autosomal dominant hereditary metabolic disorder having protean manifestations. The clinical presentations of abdominal pain, peripheral neuropathy and changes in mental status are the classic triad of an acute attack. A 15-year old girl was admitted in the medicine department of Sylhet MAG Osmani Medical College with the complaints of recurrent abdominal pain, convulsions and weakness of lower limbs. She presented with a combination of medical and neuropsychiatric symptoms suggestive of a case of AIP. The clinical presentation and the presence of porphyrins in urine confirmed the diagnosis of AIP. AIP can be life-threatening, so an accurate diagnosis and proper management are highly important.

Gastrointestinal manifestations as initial presenting features in a 40 years old woman with systemic lupus erythematosus

Gastrointestinal (GI) symptoms are common in patients with systemic lupus erythematosus (SLE). These symptoms can be due to primary GI disorders like peptic ulcer disease, pancreatitis or intestinal obstruction. But they can be due to SLE itself or complications of treatment of SLE. In this case report, we describe a 40 years old woman who presented initially with GI complaints. Later she was diagnosed as a case of SLE with chronic intestinal pseudo-obstruction (CIPO). The problems related to diagnosis and management is also discussed.

Outcomes after implementing a tailored endoscopic step-up approach to walled-off necrosis in acute pancreatitis

BACKGROUND

The aim of the study was to compare the outcomes of patients with pancreatic or peripancreatic walled-off necrosis by endoscopy using the conventional approach versus an algorithmic approach based on the collection size, location and stepwise response to intervention.

METHODS

This was an observational before-after study of consecutive patients managed over two time intervals. In the initial period (2004-2009) symptomatic patients with walled-off necrosis underwent conventional single transmural drainage with placement of two stents and a nasocystic catheter, followed by direct endoscopic necrosectomy, if required. In the later period (2010-2013) an algorithmic approach was adopted based on size and extent of the walled-off necrosis and stepwise response to intervention. The main outcome was treatment success, defined as a reduction in walled-off necrosis size to 2 cm or less on CT after 8 weeks.

RESULTS

Forty-seven patients were treated in the first interval and 53 in the second. There was no difference in patient demographics, clinical or walled-off necrosis characteristics and laboratory parameters between the groups, apart from a higher proportion of women and Caucasians in the later period. The treatment success rate was higher for the algorithmic approach compared with conventional treatment (91 versus 60 per cent respectively; P < 0·001). On multivariable logistic regression, management based on the algorithm was the only predictor of treatment success (odds ratio 6·51, 95 per cent c.i. 2·19 to 19·37; P = 0·001).

CONCLUSION

An algorithmic approach to pancreatic and peripancreatic walled-off necrosis, based on the collection size, location and stepwise response to intervention, resulted in an improved rate of treatment success compared with conventional endoscopic management.

Characterization of some representative soils from the Ganges floodplain of Bangladesh

DOI: http://dx.doi.org/10.3329/dujbs.v21i2.11519Dhaka Univ. J. Biol. Sci. 21(2): 201-205, 2012 (July)

Aspects of infection in intensive care unit--prevention and control

Nosocomial infections are the main source of infection in a hospitalized patient. Source of contaminant may be multiple. In a cardiac ICU the vulnerable open heart surgery patients are with multiple invasive lines and monitors. Pediatrics and neonates are more vulnerable because of their poor immunity and nutritional debility. Frequent indwelling line access makes a patient more prone to systemic infection with variable organisms. Our aim is to minimize the chances of hospital acquired infection as far as possible by the use of systemic approach to the patients as guided by the international standard hospital protocol.

Salmonella-a new threat to neonates

Hospital admitted 582 neonates with suspected septicaemia were studied in Microbiology Department of Dhaka Medical College, Dhaka, Bangladesh. Samples being taken from neonatal unit of Dhaka Medical College Hospital and a Neonatal Private Hospital in one year (January to December 2004). Blood culture was done by Lytic-centrifugation method. The isolated organisms were identified using standard laboratory procedures. Among 582 sick neonates 59(10.14%) were culture positive and the predominant organisms were Gram Negative Bacteria (89.83%). Among the isolates Klebsiella spp. was the prime organism (33.90%). Salmonella was observed as the 2nd most common cause (22.03%) for sepsis of neonates. Of these isolated Salmonella strains 46.15% were Salmonella typhi and 53.85% were Salmonella spp. Next to Imipenem, Ciprofloxacin was observed as the drug of choice for treatment of Sepsis neonatorum.

Effects of extremely low frequency magnetic field on fertility of adult male and female rats

To investigate the effects of an extremely low-frequency (ELF) magnetic field on their fertility, adult male and female Sprague-Dawley rats were exposed to a 50 Hz sinusoidal magnetic field of approximately 25 microT (rms) for 90 days before they were mated with unexposed counterparts. Exposure to a 50 Hz field reduced male rat fertility. The number of pregnant females was reduced when mated with exposed males, and the number of resorptions increased. The effects of magnetic field on male fertility were shown to be partly reversible, when the same exposed group of males were remated 45 and 90 days after being removed from the fields. Exposure of adult female rats to 50 Hz magnetic fields for 90 days before mating significantly reduced their fertility. The mean numbers of implantations and living fetuses per litter were statistically significantly decreased in the 50 Hz group. These results suggest that low frequency magnetic fields have some adverse effects on fertility of male and female rats.

Investigation of the nonlinearity in the heart rate dynamics

This paper presents the application of a neural network to predict human heart rate. Electrocardiograms were measured from 5 healthy adult human subjects and 5 data sets were constructed calculating instantaneous heart rate from the measured signal. The nonlinear radial basis function neural network was applied to have a one step ahead prediction of the 1000 point heart rate. The results of the prediction are compared to that obtained by a linear autoregressive model. The results show that the neural network performs better than the autoregressive model in predicting heart rate for 2 data sets while for the other 3 data sets the performance of the two models is statistically similar. This indicates that the heart rate may be controlled nonlinearly by the autonomic nervous system.

Efficient gene transfer to airway epithelium using recombinant Sendai virus

Clinical studies of gene therapy for cystic fibrosis (CF) suggest that the key problem is the efficiency of gene transfer to the airway epithelium. The availability of relevant vector receptors, the transient contact time between vector and epithelium, and the barrier function of airway mucus contribute significantly to this problem. We have recently developed recombinant Sendai virus (SeV) as a new gene transfer agent. Here we show that SeV produces efficient transfection throughout the respiratory tract of both mice and ferrets in vivo, as well as in freshly obtained human nasal epithelial cells in vitro. Gene transfer efficiency was several log orders greater than with cationic liposomes or adenovirus. Even very brief contact time was sufficient to produce this effect, and levels of expression were not significantly reduced by airway mucus. Our investigations suggest that SeV may provide a useful new vector for airway gene transfer.

Versatility of the accessory C proteins of Sendai virus: contribution to virus assembly as an additional role

The P/C mRNA of Sendai virus (SeV) encodes a nested set of accessory proteins, C', C, Y1, and Y2, referred to collectively as C proteins, using the +1 frame relative to the open reading frame of phospho (P) protein and initiation codons at different positions. The C proteins appear to be basically nonstructural proteins as they are found abundantly in infected cells but greatly underrepresented in the virions. We previously created a 4C(-) SeV, which expresses none of the four C proteins, and concluded that the C proteins are categorically nonessential gene products but greatly contribute to viral full replication and infectivity (A. Kurotani et al., Genes Cells 3:111-124, 1998). Here, we further characterized the 4C(-) virus multiplication in cultured cells. The viral protein and mRNA synthesis was enhanced with the mutant virus relative to the parental wild-type (WT) SeV. However, the viral yields were greatly reduced. In addition, the 4C(-) virions appeared to be highly anomalous in size, shape, and sedimentation profile in a sucrose gradient and exhibited the ratios of infectivity to hemagglutination units significantly lower than those of the WT. In the WT infected cells, C proteins appeared to colocalize almost perfectly with the matrix (M) proteins, pretty well with an external envelope glycoprotein (hemagglutinin-neuraminidase [HN]), and very poorly with the internal P protein. In the absence of C proteins, there was a significant delay of the incorporation of M protein and both of the envelope proteins, HN and fusion (F) proteins, into progeny virions. These results strongly suggest that the accessory and basically nonstructural C proteins are critically required in the SeV assembly process. This role of C proteins was further found to be independent of their recently discovered function to counteract the antiviral action of interferon-alpha/beta. SeV C proteins thus appear to be quite versatile.

Sendai virus gene start signals are not equivalent in reinitiation capacity: moderation at the fusion protein gene

In paramyxovirus transcription, viral RNA polymerase synthesizes each monocistronic mRNA by recognizing the gene start (S) and end (E) signals flanking each gene. These signal sequences are well conserved in the virus family; nevertheless, they do exhibit some variations even within a virus species. In Sendai virus (SeV) Z strain, the E signals are identical for all six genes but there are four (N, P/M/HN, F, and L) different S signals with one or two nucleotide variations. The significance of these variations for in vitro and in vivo replication has been unknown. We addressed this issue by SeV reverse genetics. The luciferase gene was placed between the N and P gene so that recombinant SeVs expressed luciferase under the control of each of the four different S signals. The S signal for the F gene was found to drive a lower level of transcription than that of the other three, which exhibited comparable reinitiation capacities. The polar attenuation of SeV transcription thus appeared to be not linear but biphasic. Then, a mutant SeV whose F gene S signal was replaced with that used for the P, M, and HN genes was created, and its replication capability was examined. The mutant produced a larger amount of F protein and downstream gene-encoded proteins and replicated faster than wild-type SeV in cultured cells and in embryonated eggs. Compared with the wild type, the mutant virus also replicated faster in mice and was more virulent, requiring a dose 20 times lower to kill 50% of mice. On the other hand, the unique F start sequence as well as the other start sequences are perfectly conserved in all SeV isolates sequenced to date, including highly virulent fresh isolates as well as egg-adapted strains, with a virulence several magnitudes lower than that of the fresh isolates. This moderation of transcription at the F gene may therefore be relevant to viral fitness in nature.

Detection of Shigellae from stools of dysentery patients by culture and polymerase chain reaction techniques

In Bangladesh, the isolation rates of Shigella spp. range from 11% to 12% by the conventional culture technique. Since the sensitivity of this technique is low, the polymerase chain reaction (PCR) technique was used for detecting small number of Shigellae from patients' stools. Sensitivity and specificity of the two techniques were also compared. Stool samples were collected from 41 patients with dysentery who attended the Clinical Research and Service Centre of the ICDDR,B: Centre for Health and Population Research. All stool specimens were directly plated onto MacConkey, Salmonella-Shigella, Xylose lysin deoxycholate and Hectoen enteric agar media, and Shigellae were detected following standard procedures. DNA was extracted from the stool samples, and the target sequence of invasive plasmid antigen (ipa)H locus was amplified by PCR with 130 ng each of two primers (primer H8 [5'-GTTCCTTGACCGCCTTTCCGATAC-3'] and primer H15 [5'-GCCGGTCAGCCACCCTA-3']) following standard procedures. The amplified product was hybridized using an ipaH probe. The isolation rates of Shigella dysenteriae type 1, S. flexneri, S. sonnei, and S. boydii were, respectively, 17.1%, 19.5%, 4.9% and 2.4% by the conventional method. The results of the PCR technique showed that 700 bp fragment was generated in 18 of the 18 culture-positive and in 7 of the 23 culture-negative stools. One hundred twenty-three strains of Escherichia coli were also tested by PCR for identifying the enteroinvasive E. coli, but none of them yielded any positive result. This study showed that the sensitivity of the culture technique is 72% and specificity is 100%, when the PCR technique was considered as gold standard. Therefore, the PCR may be considered a more sensitive and specific technique than the conventional culture technique and has the potential to be employed in routine diagnosis of dysentery in clinical centres as well as in epidemiologic studies.

Large quantity production with extreme convenience of human SDF-1alpha and SDF-1beta by a Sendai virus vector

We describe a robust expression of human stromal cell-derived factor-1alpha (SDF-1alpha) and SDF-1beta, the members of CXC-chemokine family, with a novel vector system based upon Sendai virus, a non-segmented negative strand RNA virus. Recombinant SDF-1alpha and SDF-1beta were detected as a major protein species in culture supernatants, reached as high as 10 microg/ ml. This remarkable enrichment of the products allowed us to use even the crude supernatants as the source for biological and antiviral assays without further concentration nor purification and will thus greatly facilitate to screen their genetically engineered derivatives.

Creation of an infectious recombinant Sendai virus expressing the firefly luciferase gene from the 3' proximal first locus

A genetic engineering approach was made to generate a recombinant non-segmented negative-strand RNA virus, Sendai virus (SeV) of the family Paramyxoviridae, that expresses firefly luciferase. The DNA construct containing the entire open reading frame (ORF) of the luciferase gene followed by the SeV transcription stop and restart signals connected with the conserved intergenic three nucleotides was inserted immediately before the ORF of the viral 3'-proximal nucleocapsid (N) protein gene in a full-length SeV cDNA copy. After intracellular expression of full-length antigenomic transcripts from the engineered cDNA and of the viral n ucleocapsid protein and RNA polymerase from the respective plasmids, a recombinant SeV expressing luciferase activity at a high level was recovered, although the tendency of this particular reporter gene product to aggregate in cells made it difficult to estimate the maximum level of expression. The increase in genome length brought about by inserting 1728 nucleotides into the 15,384 nucleotide parental SeV was associated with reduced plaque size, slightly slower replication kinetics and a severalfold decrease in yield of the virus. The inserted luciferase gene was stably maintained after numerous rounds of replication by serial passages in chick embryos. These results indicate the potential utility of SeV as a novel expression vector.

In vivo sequence variability of human immunodeficiency virus type 1 envelope gp120: association of V2 extension with slow disease progression

According to the rate of depletion of CD4 cell counts, we grouped 12 cases of human immunodeficiency virus type 1 (HIV-1) infection as 6 rapid (21.0 to 33.8 cells per microl per month) and 6 slow (0.9 to 7.9 cells per microl per month) progressors and determined the individual viral quasispecies patterns by sequencing the genome region encoding the V1, V2, and V3 loops of envelope protein. Although the quasispecies structures varied widely from one individual to another, a strong correlation was observed between a low rate of disease progression and a high degree of genetic diversity of HIV-1. Furthermore, the V2 loop extension was observed specifically in individuals with slow or no disease progression, whereas basic amino acid substitutions in V3 characteristic of a viral phenotype shift from non-syncytium inducing to syncytium inducing were observed in patients with advanced stages of disease regardless of their rate of disease progression. Studies with recombinant viruses suggested that elongation of V2 potentially restricts the capacity of HIV-1 to replicate in macrophages. Thus, our results suggest the association of distinct sequence features of both V3 and V2 with particular patterns of disease progression. Elongation of the V2 loop may be a good predictor of slow disease progression, while basic substitutions of V3 without elongation of V2 are characteristic of rapid progression.

Sendai virus-based expression of HIV-1 gp120: reinforcement by the V(-) version

BACKGROUND

We have established a system for recovering Sendai virus (SeV), a nonsegmented negative strand RNA virus, entirely from cDNA at an extremely high rate, and have succeeded in creating a V(-) SeV whose gene expression was greatly enhanced by the deletion of the nonessential V gene. Because of its extreme medical importance, there has been a strong need for the establishment of a better system to express the gp120 envelope glycoprotein of the human immunodeficiency virus type 1 (HIV-1) in sufficient quantity and purity. It also remains to be established to produce gp120 in in vitro natural host cells for HIV-1 such as human primary blood mononuclear cells, macrophages or established T cell lines.

RESULTS

Using the above system, we created recombinant Sendai viruses expressing the gp120 in CV1 cells, a monkey kidney line. The expression level from the standard V(+) version has already reached 2.2/microg per 10(6) infected cells, which was readily purified from the culture fluid with a recovery rate of about 60%, and has so far appeared to be functionally and serologically authentic. The inserted gp120 gene was stably maintained during numerous passages of the recombinant virus. The V(-) version-based expression was even more robust, consistently reaching over 6.0 microg per 10(6) cells, a level that is one of the highest currently attainable for gp120 production in mammalian cells. Furthermore, a broad host range of SeV allowed gp120 production in all the three natural host cells for HIV-1 described above.

CONCLUSIONS

SeV-based expression serves as a novel choice for producing large quantities of HIV-1 gp120 and will greatly facilitate biochemical, biological and immunological studies of this important glycoprotein.

Infectivities of human and other primate lentiviruses are activated by desialylation of the virion surface

The envelope protein, gp120, of human immunodeficiency virus type 1 (HIV-1) is heavily glycosylated and sialylated. The heavy sialylation greatly affects the physical properties of the protein, as it resolves into a wide acidic pH range despite the basic pI value predicted for its polypeptide backbone (B. S. Stein and E. G. Engleman, J. Biol. Chem. 265:2640-2649, 1990). However, the functional significance of the heavy sialylation remains elusive. Here, we show that desialylation of HIV-1 with neuraminidase greatly augments the initial virus-cell interaction, leading to remarkably enhanced viral replication and cytopathogenicity. This enhancement appeared to be a direct result of the removal of negatively charged sialic acids but not of the exposure of galactose residues or complement activation. Complementing these results, studies with inhibitors of mannosidase I and mannosidase II showed that the processing of HIV-1 oligosaccharides into the complex type to acquire the terminal sialic acid residues impeded the full replication capacity of the virus and that its prevention also enhanced virus replication and cytopathogenicity. Enhancement of infection by desialylation was found widely, with HIV-1 laboratory strains of different cell tropisms and primary isolates as well as HIV-2 and simian immunodeficiency virus. Thus, the sialylation catalyzed by host cell pathways appeared to reduce the infectivity of human and nonhuman primate lentiviruses. Our results further suggested that desialylation would help increase the titers of HIV-based vectors.

Mental health reform: a practical approach

This paper outlines a practical and pragmatic approach to containing mental health costs, especially when caring for Medicaid recipients. The role of psychiatrists as primary care gatekeepers in the managed care system is also discussed. We conclude that a single-payor system seems to be the best alternative for timely and quality mental health care, and that early detection via education and screening for families predisposed to substance abuse/mental illness is also beneficial in controlling costs.

Alzheimer's disease: a new hope

Until recently, the diagnosis and treatment of Alzheimer's disease was limited. This article describes the outcome of new research and advances in the pharmacological treatment of this disease, especially the use of Cognex (tacrine). It also reports on a multicenter study of tacrine we participated in with patients at Raleigh Psychiatric Services, Inc. in Beckley.