Altered long non-coding RNAs expression in normal and diseased primary human airway epithelial cells exposed to diesel exhaust particles.

BACKGROUND: Exposure to diesel exhaust particles (DEP) has been linked to a variety of adverse health effects, including increased morbidity and mortality from cardiovascular diseases, chronic obstructive pulmonary disease (COPD), metabolic syndrome, and lung cancer. The epigenetic changes caused by air pollution have been associated with increased health risks. However, the exact molecular mechanisms underlying the lncRNA-mediated pathogenesis induced by DEP exposure have not been revealed. METHODS: Through RNA-sequencing and integrative analysis of both mRNA and lncRNA profiles, this study investigated the role of lncRNAs in altered gene expression in healthy and diseased human primary epithelial cells (NHBE and DHBE-COPD) exposed to DEP at a dose of 30 µg/cm2. RESULTS: We identified 503 and 563 differentially expressed (DE) mRNAs and a total of 10 and 14 DE lncRNAs in NHBE and DHBE-COPD cells exposed to DEP, respectively. In both NHBE and DHBE-COPD cells, enriched cancer-related pathways were identified at mRNA level, and 3 common lncRNAs OLMALINC, AC069234.2, and LINC00665 were found to be associated with cancer initiation and progression. In addition, we identified two cis-acting (TMEM51-AS1 and TTN-AS1) and several trans-acting lncRNAs (e.g. LINC01278, SNHG29, AC006064.4, TMEM51-AS1) only differentially expressed in COPD cells, which could potentially play a role in carcinogenesis and determine their susceptibility to DEP exposure. CONCLUSIONS: Overall, our work highlights the potential importance of lncRNAs in regulating DEP-induced gene expression changes associated with carcinogenesis, and individuals suffering from COPD are likely to be more vulnerable to these environmental triggers.

Formation of Redox-Active Duroquinone from Vaping of Vitamin E Acetate Contributes to Oxidative Lung Injury.

In late 2019, the outbreak of e-cigarette or vaping-associated lung injuries (EVALIs) in the United States demonstrated to the public the potential health risks of vaping. While studies since the outbreak have identified vitamin E acetate (VEA), a diluent of tetrahydrocannabinol (THC) in vape cartridges, as a potential contributor to lung injuries, the molecular mechanisms through which VEA may cause damage are still unclear. Recent studies have found that the thermal degradation of e-liquids during vaping can result in the formation of products that are more toxic than the parent compounds. In this study, we assessed the role of duroquinone (DQ) in VEA vaping emissions that may act as a mechanism through which VEA vaping causes lung damage. VEA vaping emissions were collected and analyzed for their potential to generate reactive oxygen species (ROS) and induce oxidative stress-associated gene expression in human bronchial epithelial cells (BEAS-2B). Significant ROS generation by VEA vaping emissions was observed in both acellular and cellular systems. Furthermore, exposure to vaping emissions resulted in significant upregulation of NQO1 and HMOX-1 genes in BEAS-2B cells, indicating a strong potential for vaped VEA to cause oxidative damage and acute lung injury; the effects are more profound than exposure to equivalent concentrations of DQ alone. Our findings suggest that there may be synergistic interactions between thermal decomposition products of VEA, highlighting the multifaceted nature of vaping toxicity.

Integrative Analysis of lncRNA-mRNA Coexpression in Human Lung Epithelial Cells Exposed to Dimethyl Selenide-Derived Secondary Organic Aerosols.

Dimethyl selenide (DMSe) is one of the major volatile organoselenium compounds released into the atmosphere through plant metabolism and microbial methylation. DMSe has been recently revealed as a precursor of secondary organic aerosol (SOA), and its resultant SOA possesses strong oxidizing capability toward thiol groups that can perturb several major biological pathways in human airway epithelial cells and is linked to genotoxicity, DNA damage, and p53-mediated stress responses. Mounting evidence has suggested that long noncoding RNAs (lncRNAs) are involved in stress responses to internal and environmental stimuli. However, the underlying molecular interactions remain to be elucidated. In this study, we performed integrative analyses of lncRNA-mRNA coexpression in the transformed human bronchial epithelial BEAS-2B cell line exposed to DMSe-derived SOA. We identified a total of 971 differentially expressed lncRNAs in BEAS-2B cells exposed to SOA derived from O3 and OH oxidation of DMSe. Gene ontology (GO) network analysis of cis-targeted genes showed significant enrichment of DNA damage, apoptosis, and p53-mediated stress response pathways. trans-Acting lncRNAs, including PINCR, PICART1, DLGAP1-AS2, and LINC01629, known to be associated with human carcinogenesis, also showed altered expression in cell treated with DMSe-SOA. Overall, this study highlights the regulatory role of lncRNAs in altered gene expression induced by DMSe-SOA exposure.

Chemical and Toxicological Characterization of Vaping Emission Products from Commonly Used Vape Juice Diluents.

Recent reports have linked severe lung injuries and deaths to the use of e-cigarettes and vaping products. Nevertheless, the causal relationship between exposure to vaping emissions and the observed health outcomes remains to be elucidated. Through chemical and toxicological characterization of vaping emission products, this study demonstrates that during vaping processes, changes in chemical composition of several commonly used vape juice diluents (also known as cutting agents) lead to the formation of toxic byproducts, including quinones, carbonyls, esters, and alkyl alcohols. The resulting vaping emission condensates cause inhibited cell proliferation and enhanced cytotoxicity in human airway epithelial cells. Notably, substantial formation of the duroquinone and durohydroquinone redox couple was observed in the vaping emissions from vitamin E acetate, which may be linked to acute oxidative stress and lung injuries reported by previous studies. These findings provide an improved molecular understanding and highlight the significant role of toxic byproducts in vaping-associated health effects.

Exposure to Dimethyl Selenide (DMSe)-Derived Secondary Organic Aerosol Alters Transcriptomic Profiles in Human Airway Epithelial Cells.

Dimethyl selenide (DMSe) is one of the major volatile organoselenium compounds released from aquatic and terrestrial environments through microbial transformation and plant metabolism. The detailed processes of DMSe leading to secondary organic aerosol (SOA) formation and the pulmonary health effects induced by inhalation of DMSe-derived SOA remain largely unknown. In this study, we characterized the chemical composition and formation yields of SOA produced from the oxidation of DMSe with OH radicals and O3 in controlled chamber experiments. Further, we profiled the transcriptome-wide gene expression changes in human airway epithelial cells (BEAS-2B) after exposure to DMSe-derived SOA. Our analyses indicated a significantly higher SOA yield resulting from the OH-initiated oxidation of DMSe. The oxidative potential of DMSe-derived SOA, as measured by the dithiothreitol (DTT) assay, suggested the presence of oxidizing moieties in DMSe-derived SOA at levels higher than typical ambient aerosols. Utilizing RNA sequencing (RNA-Seq) techniques, gene expression profiling followed by pathway enrichment analysis revealed several major biological pathways perturbed by DMSe-derived SOA, including elevated genotoxicity, DNA damage, and p53-mediated stress responses, as well as downregulated cholesterol biosynthesis, glycolysis, and interleukin IL-4/IL-13 signaling. This study highlights the significance of DMSe-derived SOA as a stressor in human airway epithelial cells.

Coronary Artery Bypass Graft with Endarterectomy and Stent Removal in Patient with Multivessel in Stent Restenosis.

In the age of stent deployment after balloon angioplasty. In stent restenosis (ISR) has become a major concern. Various coronary interventional measures and coronary artery bypass graft (CABG) has employed to manage the ISR. Although CABG seems to offer advantages over other coronary intervention methods in patients with multi vessel ISR; lack of appropriate graftable vessels often make the surgery difficult and end up with incomplete revascularization. Coronary endarterectomy with stent removal mitigated some of the limitations of CABG but initial results of this surgical measure were not favorable. Later, with improvement of surgical technique and meticulous anticoagulant therapy along with CABG showed promising result but till date only few cases have been reported. Here, we are reporting a case of 65 years old lady who underwent CABG along with endarterectomy with stent removal after she had developed stent restenosis in three vessels. This diabetic and hypertensive patient presented with chest pain and shortness of breath which was developed within three months of PCI with stent deployment in three vessels. Angiogram done prior to admission in the cardiac surgery department reveals restenosis in all the three stented vessels. CABG was done and three grafts given in LIMA to LAD, RSVG to OM and RCA. Endarterectomy done on LAD and RCA with stent removal from RCA. Postoperative anticoagulant therapy was strictly maintained. Patient's postoperative period remained eventless other than superficial wound infection. With skilled hand capable of handling highly technique demanding surgery and postoperative anticoagulation maintenance; endarterectomy along with CABG seems to be safe solution for multi vessel ISR with diffuse coronary artery disease.

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.

Use of Anticoagulant Warfarin in Patients Presenting With Atrial Fibrillation in a Tertiary Level Hospital.

Atrial fibrillation (AF) is the most common sustained arrhythmia in the World, occurring in approximately 0.4% of the general population. The purpose of the present study was to see the trend of use of warfarin in hospital admitted patients with atrial fibrillation. It was conducted in the department of cardiology, University Cardiac Centre, Bangabandhu Sheikh Mujib Medical University, Dhaka, Bangladesh from January 2008 to January 2009. A total of 150 patients with atrial fibrillation were enrolled in this study. Out of them, male were 60(40%) and female 90(60%); age range 22-79 years. Most common presenting symptoms were palpitation (80%) & dyspnoea (70%). Chronic rheumatic heart disease (Mitral stenosis) (33%) was found in most cases followed by IHD (22%), hypertension (21%). According to CHADS2 score, most of the patients belonged to moderate risk group (47%) and 32% in low risk group. Anticoagulation with warfarin was used in 40% cases of valvular AF & 25% patients with non valvular AF. Among non valvular AF, it was prescribed for 38% in high risk group, 34% in moderate risk & 3% in low risk group. The study states that warfarin is underused in both valvular & non valvular AF.

Noninvasive carotid duplex study may be used as predictor test for ischaemic heart disease.

A prospective observational study was carried out to detect carotid atherosclerosis using high resolution B-Mode in 150 in-hospital patients with clinically diagnosed ischemic heart disease in various forms in the department of Cardiology, University Cardiac Center, BSMMU, Bangladesh. The duration of study was from April 2006 to December 2008. Carotid Ultrasound evaluation was performed in 150 patients diagnosed as Ischemic Heart Disease by single operator (NF). Mean age of the patients was 53.62±10.92 with, male to female ratio of 9.5:0.5. Mean IMT was 0.96±0.21mm in 85% of the patient of clinically diagnosed IHD, which was higher than the normal (normal IMT ≤0.8mm). Among them, about 77% had atherosclerotic plaque. A significant correlation between Carotid atherosclerosis determined by IMT and Ischemic Heart Disease (IHD) was found. Non invasive carotid duplex study might be useful for predicting ischaemic heart disease.

Comparative Study on Clinical and Echocardiographic Findings in Ischemic Heart Disease Patients with or without Mitral Annular Calcification in a Tertiary Hospital.

The presence of bright resonance of more than 1 mm or more cusps of the aortic valve, mitral valve or mitral annulus is termed as cardiac valve calcification. If an intense echo producing structure located at the junction of the atrioventricular groove and posterior mitral valve leaflet on Echocardiography that is Mitral annular calcification (MAC). This study was conducted to observe the association of MAC with clinical and echocardiographic findings of ischemic heart disease (IHD) and the role of trans-thoracic echocardiography to detect MAC which is a marker IHD. In this prospective, observational, case-control study, total of 100 IHD patients, 50 patients with MAC were assigned as case group and 50 patients without MAC were control group after fulfilling inclusion criteria. All the detailed history, clinical examination and relevant investigation reports of each patient were recorded in pre designed data collection sheet. MAC was detected with transthorasic echocardiography. Analysis was done to observe the association and correlation of MAC with clinical findings of IHD. Mean age of the case control was 55.16±10.73 years and control was 49.80±8.84 years. MAC was noted highest about 56.0% in between age 45 to 60 years. Eighty two percent (82.0%) of cases and 84.0% of controls were male, 18.0% of cases and 16.0% of controls were female. BMI among the MAC group 2.0% were underweight, 72.0% normal, 24.0% over weight and 2.0% were obese and among non MAC controls group 10.0% were underweight, 68.0% normal, 20.0% over weight and 2.0% were obese. Clinically among cases 14(28.0%) had Stable angina, 8(16.0%) had UA, 3(6.0%) had Non STEMI, 2(4.0%) had AMI, 2(4.0%) had Recent myocardial infarction and 21(42.0%) had OMI. Diabetes mellitus was significantly higher in the case groups (p=0.006). Significant p-value was noted in hyper-triyglyceridemia and low HDL in case group than control. Echocardiographic studies showed 52.0% of cases and 32.0% of controls had regional wall motion abnormality (RWMA). Transthorasic echocardiographically detected MAC is an independent predictor of Ischemic heart disease. The low cost, portable and radiation free nature of the ultrasound approach make MAC an attractive parameter in the ongoing search for IHD.

Cross study analyses of SEND data: toxicity profile classification.

A SEND toxicology data transformation, harmonization and analysis platform was created to improve the identification of unique findings related to the intended target, species, and duration of dosing using data from multiple studies. The lack of a standardized digital format for data analysis had impeded large-scale analysis of in vivo toxicology studies. The CDISC SEND standard enables the analysis of data from multiple studies performed by different laboratories. This work describes methods to analyze data and automate cross study analysis of toxicology studies. Cross study analysis can be used to understand a single compound's toxicity profile across all studies performed and/or to evaluate on-target versus off-target toxicity for multiple compounds intended for the same pharmacological target. This work involved development of data harmonization/transformation strategies to enable cross-study analysis of both numerical and categorical SEND data. Four de-identified SEND data sets from the BioCelerate database were used for the analyses. Toxicity profiles for key organ systems were developed for liver, kidney, male reproductive tract, endocrine system, and hematopoietic system using SEND domains. A Cross-Study Analysis dashboard with a built-in user-defined scoring system was created for custom analyses, including visualizations to evaluate data at the organ system level and drill down into individual animal data. This data analysis provides the tools for scientists to compare toxicity profiles across multiple studies using SEND. A cross-study analysis of two different compounds intended for the same pharmacological target is described and the analyses indicate potential on-target effects to liver, kidney, and hematopoietic systems.

Echocardiographic assessment of cardiac involvement in systemic lupus erythematosus patients.

This study was designed to assess cardiac abnormalities in patients with systemic lupus erythematosus (SLE) by echocardiography. It was an analytic type of cross sectional study, conducted in lupus clinic, Bangabandhu Sheikh Mujib Medical University (BSMMU), Dhaka, Bangladesh from July 2008 to June 2009. Fifty lupus patients, diagnosed on the basis of ACR criteria, without cardiovascular symptoms, were enrolled in the study and were evaluated by standard echocardiography with color Doppler. SLEDAI was applied for assessment of disease activity. Out of 50 patients 80% had abnormal echocardiographic findings. Pericardial thickening was found in 38% patients, pericardial effusion 20%, diastolic dysfunction 72%, hypokinesia of ventricular wall 8%, overall valvular abnormalities 20%, commonest being aortic regurgitation (12%), followed by mitral regurgitation (8%), and 6% had pulmonary hypertension. Males (100%) were more vulnerable to cardiac involvement than females (68.2%) and later age of disease onset (31-40 years) was associated with higher (87.5%) chance of echo abnormalities. The differences, however, were not statistically significant (p>0.05). There was significant relationship between disease duration and cardiac abnormalities (p<0.01). Active disease (80.08%) was associated with higher frequency of cardiac involvement than disease in remission (62.50%) but the result was not statistically significant (p=0.151). Cardiac abnormalities are very common in lupus patients even when clinically asymptomatic from cardiac aspect. Echocardiography is an excellent non-invasive tool for cardiac evaluation. These observations emphasize a need for further assessment of early intervention to reduce subsequent cardiac morbidity and mortality among the lupus patients.

First Cardiac Magnetic Resonance Experience in Bangladesh: A Case of Arrhythmogenic Right Ventricular Dysplasia.

Arrhythmogenic right ventricular dysplasia (ARVD) is a progressive degeneration and replacement of the right ventricular (RV) myocardial tissue by fat and fibrosis and produce clinical condition. Desmosome gene mutations are only the causative state for ARVD hereditary disorder. The arrhythmogenic right ventricular cardiomyopathy incidence is about 1/1000-5000. Mostly young people and athletes are bearing the clinical presentations include presyncope, syncope, ventricular tachycardias or ventricular fibrillation leading to cardiac arrest. We report about the first case of Cardiac magnetic resonance (CMR) imaging to diagnose a case Arrhythmogenic right ventricular dysplasia (ARVD) of a 34-year-old male from Savar, Dhaka, Bangladesh who was referred to cardiac emergency for the evaluation recurrent dizzy spells.

Role of ETT to diagnose coronary artery disease.

The purpose of the study to predict the coronary arterial disease by exercise treadmill scoring system and to see the correlation of angiographic extent of coronary artery disease by high treadmill score in our country. The present prospective study carried out in the department of cardiology, Bangabandhu Sheikh Mujib Medical University, University Cardiac Centre during the period of January 2006 to July 2006. Based on inclusion and exclusion criteria a total of 80 patient of chronic stable angina or chest pain evaluation having positive ETT who were admitted in university cardiac centre in Bangabandhu Sheikh Mujib Medical University and underwent coronary angiogram within one month were the study population. Among 80 subjects 60(75%) were male and 20(25%) were female and male: female ratio 3:1 Mean age of male subject 51.37±9.08 years and mean age of female subjects were 43.75±7.67 years. Three quarter of the subject had the history of typical anginal pain followed by 21.3% atypical and 3.8% pain of non-anginal origin. All the risk factors like, dyslipidemia (90%), HTN (68.8%) past smoker (45%), current smoker (32.5%), diabetes (36.3%), family history of coronary artery disease (25%) and sudden death of first degree relatives (8.8%); dyslipidemia was the highest percentage. Among 80 subjects more than one third 35% (28) of the subjects were observed to be normal by angiogram, 28.8% (23) had SVD, 16.3% (13) DVD and 20% (16) TVD. Approximately 70% of the significant stenosis was predicted as having high probability of 30.8% as intermediate probability and none as low probability with exercise test scores. Multi-vessel coronary artery disease were predicted by high probability exercise test score 82.8%. Thus high probability score needs urgent coronary angiogram.

Comparison between 2D and 3D Echocardiography in Efficient Detection of Commissural Calcification in Rheumatic Mitral Stenosis.

Rheumatic heart disease causes a substantial number of morbidity and mortality in Southeast Asia. In Bangladesh prevalence of Rheumatic Fever and Rheumatic heart disease is still high, 0.6 and 0.3 per thousand populations, respectively. Mitral valve mostly involved in the form of mitral stenosis in the rheumatic process. Treatment selections and its success largely depend upon the severity of disease especially the extent and distribution of calcification. Echocardiography has got the key role in determining the pattern, extent and severity of mitral stenosis. Two dimensional and Doppler echocardiography are conventionally used. With the increasing availability of 3D echocardiography, better cardiac imaging is possible now. The heart being a complex three-dimensional structure, the 3D evaluation would definitely offer better imaging for accurate assessment of the severity of mitral stenosis, especially details of commissural involvements. Many scoring systems are available for the assessment of the severity of rheumatic Mintral Stenosis (MS), mostly 2DE based; among them, Wilkins is mostly practiced. This cross-sectional observational study was conducted in University Cardiac Centre, Bangabandhu Sheikh Mujib Medical University (BSMMU), Dhaka, Bangladesh from May 2012 to October 2012. Data were collected from 50 subjects who underwent transthoracic 2D and 3D Echocardiography for the assessment of rheumatic mitral stenosis especially detection of calcification also it's severity, extent, and distribution, furthermore the presence of commissural calcification. Precise measurement of Mitral valvular area is essential in the assessment of severity, which is found similar by both 2DE (0.98±0.24cm²) and 3DE (0.92±0.23cm²). But in identifying calcification and its extent especially commissural involvement is better detected by 3DE (p=0.002). This has paramount importance in therapeutic decision making of chronic rheumatic MS. To make a well-organized management plan and also for the confident prediction of complications, three-dimensional echocardiography has promising prospects in detecting commissural calcification and should be considered as an essential adjuvant to the conventional two-dimensional echocardiography.

Comparison between 2D and 3D Echocardiographic Parameters used for Diagnostic and Therapeutic Purpose in Patients with Rheumatic Mitral Stenosis.

Rheumatic heart disease causes a substantial number of morbidity and mortality in South Asia. With the increasing urbanization & antibiotic availability, it is now in declining trends. The prevalence of Rheumatic Fever and Chronic Rheumatic Heart Disease in Bangladesh is 0.6 and 0.3 per thousand populations, respectively. Mitral valve is mostly involved in the rheumatic process, particularly in the form of mitral stenosis. Treatment options of mitral stenosis depend upon the severity of the disease. Echocardiography has a key role in determining the pattern, extent and severity of the involvement of the mitral valve apparatus. 2D and Doppler echocardiography are conventionally used. 3D echocardiography is more available nowadays. The heart being a complex three-dimensional structure, a 3D evaluation would definitely offer better visualization for accurate assessment of the severity of rheumatic mitral stenosis. There are many echocardiography based scoring systems are available for the assessment of the severity of rheumatic MS. Those are mostly 2DE based; among them, Wilkins is widely practiced. Real-time 3DE based score for mitral stenosis is developed recently. This cross-sectional observational study was done in the University Cardiac Centre, Bangabandhu Sheikh Mujib Medical University (BSMMU), Dhaka, Bangladesh from May 2012 to October 2012. Considering all ethical issues, data were collected from 50 subjects who underwent transthoracic 2D and 3D Echocardiography for the assessment of the extent and severity of mitral stenosis. Precise measurement of the mitral valvular area is of a pivotal role in the assessment of severity, which is found almost similar by both 2DE (0.98±0.24cm²) and 3DE (0.92±0.23cm²). But in identifying calcification and its extent specifically commissural involvement is better detected by 3DE (p=0.002). Detail assessment of subvalvular involvement particularly chordal adhesion can better be done by 3DE (p<0.001). All of these have important contributions in formulating the most favorable therapeutic roadmap in chronic rheumatic MS. To make an efficient management plan and also for the confident prediction of complications, three-dimensional echocardiography has promising prospects and should be considered as an important adjuvant to the conventional two-dimensional echocardiography.

Balloon mitral valvuloplasty: immediate and short term haemodynamic and clinical outcome.

This prospective study was carried out in the Department of Cardiology, University Cardiac Center, Banghabandhu Sheikh Mujib Medical University, Dhaka, to evaluate the short term clinical and haemodynamic outcome of Balloon mitral valvuloplasty in mitral stenosis. Total 100 patients underwent percutaneous mitral commissurotomy out of which 60 cases had pure mitral stenosis and 40 patients had concomitant other nonsignificant valvular disease. Mitral valve dilatation increases in mitral valve area from 0.5+/-0.22 to 1.80+/-0.41 cm2. Mitral valve mean pressure gradient decline from 24.0+/-6.48 mm of Hg to 6.1+/-3.0 mm of Hg: mean left arterial pressure decline from 21.40+/-4.80 mm of Hg to 6.50+/-2.82 mm of Hg (p<0.001). The pulmonary artery systolic pressure decreased from 78.7+/-20.34 mm of Hg to 30.18+/-10.8 mm of Hg (p<0.001). Procedural success, as defined final mitral valve area>1.5 cm2 or>50% increase in area, was achieved in 95% patients. Serious complications occurred in 2(2%) patients and no death occurred in the study. Minor complications such as vasovagal reaction (03%), balloon rupture without sequelae (1%), hypotension, Seizure etc. during the procedure were also noted. Although percutaneous transvenous mistral commissurotomy appears to be effective at relieving the hemodynamic effects of rheumatic mitral stenosis, it is not without risk. In properly selected patients, however, it appears to have low morbidity and mortality. The overall results of this study demonstrate that the short term clinical and haemodynamic outcome of the procedure were excellent and the incidence of related complications were reasonable.

Correlation between severity of coronary artery stenosis and perfusion defect assessed by SPECT myocardial perfusion imaging.

Numerous non-invasive techniques are developed to assess the severity of coronary artery disease (CAD). Coronary angiography (CAG) is an established method for the diagnosis and to quantify the severity of coronary artery stenosis. Single photon emission computed tomography-myocardial perfusion imaging (SPECT-MPI) using Technetium-99m (Tc-99m) tetrofosmin is also a useful established technique for the assessment of severity of CAD. This prospective observational study was carried out in Bangabandhu Sheikh Mujib Medical University (BSMMU) to assess the severity of coronary artery stenosis using Tc-99m Single Photon Emission Computed Tomography myocardial perfusion imaging (SPECT-MPI) in comparison with CAG. Eighty two (82) consecutive patients with mean age 53.51(SD+/-7.08) years and Candian Cardiovascular Society (CCS) class I and II severity of chest pain, male: female ratio (4.8:1) was studied. Tc-99m SPECT-MPI was performed by one-day exercise stress and rest protocol. A total of two hundred and forty six coronary artery territories examined in this study. By CAG normal coronary arteries were found in seventy six, moderate stenosis in twenty four and severe stenosis in one hundred and forty-six coronary artery territories whereas SPECT-MPI found normal perfusion in twenty seven, mild perfusion abnormality in seventeen, moderate perfusion abnormality in thirty two and severe perfusion abnormality in one hundred and sixty five coronary artery territories. Sensitivity and specificity of SPECT-MPI using Tc-99m tetrofosmin in detecting coronary artery stenosis were 87.09% and 80.95% respectively. The positive predictive value, negative predictive value and accuracy of the test were 91.01%, 73.91% and 85.18% respectively. From this study it can be concluded that Tc-99m SPECT-MPI was a safe, effective and excellent non-invasive tool for the detection of severity of coronary artery lesion and can be used to predict severity of CAD.

Role of functional groups in reaction kinetics of dithiothreitol with secondary organic aerosols.

The toxicity of organic aerosols has been largely ascribed to the generation of reactive oxygen species, which could subsequently induce oxidative stress in biological systems. The reaction of DTT with redox-active species in PM has been generally assumed to be pseudo-first order, with the oxidative potential of PM being represented by the DTT consumption per minute of reaction time per µg of PM. Although catalytic reactive species such as transition metals and quinones are long believed to be the main contributors of DTT responses, the role of non-catalytic DTT reactive species such as organic hydroperoxides (ROOH) and electron-deficient alkenes (e.g., conjugated carbonyls) in DTT consumption has been recently highlighted. Thus, understanding the reaction kinetics and mechanisms of DTT consumption by various PM components is required to interpret the oxidative potential measured by DTT assays more accurately. In this study, we measured the DTT consumptions over time and characterized the reaction products using model compounds and secondary organic aerosols (SOA) with varying initial concentrations. We observed that the DTT consumption rates linearly increased with both initial DTT and sample concentrations. The overall reaction order of DTT with non-catalytic reactive species and SOA in this study is second order. The reactions of DTT with different functional groups have significantly different rate constants. The reaction rate constant of isoprene SOA with DTT is mainly determined by the concentration of ROOH. For toluene SOA, both ROOH and electron-deficient alkenes may dominate its DTT reaction rates. These results provide some insights into the interpretation of DTT-based aerosol oxidative potential and highlight the need to study the toxicity mechanism of ROOH and electron-deficient alkenes in PM for future work.

Toxicological responses in human airway epithelial cells (BEAS-2B) exposed to particulate matter emissions from gasoline fuels with varying aromatic and ethanol levels.

In this study, we assessed the toxicological potencies of particulate matter (PM) emissions from a modern vehicle equipped with a gasoline direct injection (GDI) engine when operated on eight different fuels with varying aromatic hydrocarbon and ethanol contents. Testing was conducted over the LA92 driving cycle using a chassis dynamometer with a constant volume sampling system, where particles were collected onto Teflon filters. The extracted PM constituents were analyzed for their oxidative potential using the dithiothreitol (DTT) chemical assay and exposure-induced gene expression in human airway epithelial cells (BEAS-2B). Different trends of DTT activities were seen when testing PM samples in 100% aqueous buffer solutions versus elevated fraction of methanol in aqueous buffers (50:50), indicating the effect of solubility of organic PM constituents on the measured oxidative potential. Higher aromatics content in fuels corresponded to higher DTT activities in PM. Exposure to PM exhaust upregulated the expression of HMOX-1, but downregulated the expression of IL-6, TNF-α, CCL5 and NOS2 in BEAS-2B cells. The principal component regression analysis revealed different patterns of correlations. Aromatics content contributed to more significant PAH-mediated IL-6 downregulation, whereas ethanol content was associated with decreased downregulation of IL-6. Our findings highlighted the key role of fuel composition in modulating the toxicological responses to GDI PM emissions.