Adenylyl Cyclase Isoform Specific Effects in Lipid Raft and Non-Lipid Raft Membrane Domains Regulate cAMP Compartmentation in Human Airway Smooth Muscle Cells

The formation of distinct macromolecular signaling complexes allows different G-protein coupled receptors to produce diverse functional responses, even while sharing a common second messenger such as cAMP. In human airway smooth muscle (HASM) cells, segregation of specific receptors into different membrane microdomains is thought to critically aid in generating compartmentalized cAMP responses. Whereas, E type prostaglandin receptors (EPRs) have been shown to be expressed in non-lipid raft domains of the plasma membrane, β-Adrenergic receptors (βARs) are predominantly expressed in caveolar lipid rafts. In the present study, we tested the hypothesis that adenylyl cyclase type 2 (AC2) preferentially couples to EPRs in a non-lipid raft domain, while adenylyl cyclase type 6 (AC6) selectively couples to βARs in lipid rafts. To do this, we examined the effect of overexpressing AC2 and AC6 on cAMP responses detected using genetically-encoded FRET-based biosensors targeted to lipid raft and non-lipid raft domains of the plasma membrane, as well as the bulk cytosolic compartment in HASM cells. This approach has the advantage of measuring the kinetics of cAMP production in living cells without the use of PDE inhibitors. Overexpression of AC2 enhanced the cAMP response to EPR activation associated with non-lipid raft domains, without significantly affecting responses detected elsewhere. AC2 overexpression also had no effect on cAMP responses to βAR activation detected in any subcellular location. These data confirm the hypothesis that AC2 couples exclusively with EPRs in a non-lipid raft membrane compartment. Overexpression of AC6, on the other hand, actually decreased the response to βAR stimulation associated with lipid rafts, without significantly affecting responses elsewhere. AC6 overexpression also had no effect on the responses to EPR activation detected anywhere in the cell. The ability of AC6 overexpression to inhibit βAR production of cAMP in lipid raft domains was reversed by inhibition of PDE4 activity with rolipram. It was also reversed by overexpression of Ht31 peptide, which disrupts the interaction of protein kinase A with A-kinase anchoring proteins (AKAPs). These results suggests that AC6 overexpression upregulates and/or recruits PKA and PDE4 activity, which then reduces βAR production of cAMP associated specifically with lipid raft domains

A Case of Cardiac Calcified Amorphous Tumor Presenting with Concomitant ST-Elevation Myocardial Infarction and Occipital Stroke and a Brief Review of the Literature

Cardiac calcified amorphous tumor (CAT) is an extremely rare benign intracavitary tumor of the heart. It may mimic other cardiac tumors and can present with signs or symptoms of systemic embolization. There are limited data regarding CAT in the literature. We report a case of a 68-year-old woman with a cardiac CAT and mitral annular calcification (MAC), who presented with acute ST-elevation myocardial infarction (STEMI) and occipital stroke. After extensive review of the literature, we believe that this case is possibly the first description of a cardiac CAT presenting with STEMI. The CAT was surgically removed, and the diagnosis was confirmed by histology. The patient tolerated the surgery and reported no events at 6-month follow-up

A Rare Case of Carotid Web Presenting with Ischemic Stroke in a Young Woman and a Brief Review of the Literature

Carotid web is a radiological description of a shelf-like intraluminal filling defect in the carotid bulb. It is histologically defined as atypical fibromuscular dysplasia (FMD), with abnormal fibrosis and smooth muscle cell hyperplasia in the tunica intima. The spur-like intraluminal protrusion can serve as a nidus for thrombus formation, which could cause systemic embolism and ischemic strokes. We report a case of a 20-year-old female patient presenting with acute ischemic stroke in the ipsilateral middle cerebral artery (MCA) territory. We also discuss the incidence, the prevalence, the pathophysiology, the treatment, and the recurrence of carotid web based on the currently available literature

Developing Decision Tree Using ID3 for Paddy Classification

Data Mining is the task of discoveringinteresting pattern from large amounts of data wherethe data can be stored in database, data warehouse.Data classification is the process of building a modelfrom available data called the training data set andclassifying objects according to their attributes.Decision tree algorithms have been used forclassification in a wide range of applicationdomains. The aim of this paper is to study aboutdecision tree algorithm. This system is intended todevelop the type of Myanmar’s paddy data by usingdecision tree induction classification algorithm,Depending upon the data tuples of paddy dataset, thesystem can classify the type of paddy data whether itis good or bad quality and quantity

Coronary artery ectasia presenting with acute inferior wall myocardial infarction in a young adult

Coronary artery ectasia (CAE), a variant of coronary artery anomalies, is a rare clinical entity. Although atherosclerotic coronary artery disease (CAD) is the most common cause of acute coronary syndrome (ACS), CAE also conveys a relatively high risk for potentially life-threatening cardiac events. We report a case of a 35-year-old male with two-vessel CAE, who presented with acute inferior wall ST election myocardial infarction (STEMI). After initiating medical therapy including bivalirudin, emergent percutaneous coronary intervention (PCI) with stenting of postero-lateral branch of right coronary artery (RCA) was performed. Coronary angiography also showed diffuse ectasia of RCA and left anterior descending artery (LAD). The patient tolerated the procedure well and was discharged on appropriate medical therapy. He was followed-up at one month, with no resulting cardiac events. This case highlights the importance of CAE awareness. CAE has drawn the attention of clinicians because of its clinical implications, as well as its seemingly higher prevalence, due to the abundant use of coronary angiograms and advanced cardiac imaging in the contemporary world. Albeit there has been much progress in the understanding and management of the disease, questions still remain regarding the exact pathophysiology, management guidelines and prognosis of CAE, which are worth further study

A Case of Cardiac Calcified Amorphous Tumor Presenting with Concomitant ST-Elevation Myocardial Infarction and Occipital Stroke and a Brief Review of the Literature

Cardiac calcified amorphous tumor (CAT) is an extremely rare benign intracavitary tumor of the heart. It may mimic other cardiac tumors and can present with signs or symptoms of systemic embolization. (ere are limited data regarding CAT in the literature. We report a case of a 68-year-old woman with a cardiac CATand mitral annular calcification (MAC), who presented with acute ST-elevation myocardial infarction (STEMI) and occipital stroke. After extensive review of the literature, we believe that this case is possibly the first description of a cardiac CATpresenting with STEMI. The CAT was surgically removed, and the diagnosis was confirmed by histology. The patient tolerated the surgery and reported no events at 6-month follow-up

A classic case of arrhythmogenic right ventricular cardiomyopathy (ARVC) and literature review

Arrhythmogenic Right Ventricular Cardiomyopathy (ARVC) is a relatively under-recognized hereditary cardiomyopathy. It is characterized pathologically by fibro-fatty infiltration of right ventricular (RV) myocardium and clinically by consequences of RV electrical instability. Timely intervention with device therapy and pharmacotherapy may help reduce the risk of arrhythmic events or sudden cardiac death. Here, we describe a classic case of a young adult with ARVC and a brief literature review. The patient presented with exertional palpitations and ARVC was suspected after his routine electrocardiogram (EKG) revealed symmetric T wave inversions and possible epsilon waves in right precordial leads. Subsequent work up showed fatty infiltration of RV myocardium on cardiac magnetic resonance imaging and inducible ventricular tachycardia from the right ventricle during electrophysiologic study. Those findings confirmed the diagnosis of ARVC and warranted treatment with implantable cardioverter defibrillator. It is always exciting to encounter rare pathological entities with classic clinical findings, especially when they present as a diagnostic challenge.We were able to provide correct diagnosis and management, thereby preventing the potentially lethal consequences. Therefore, it is important to recognize the possible EKG findings of ARVC and to know when to pursue further investigations and to implement therapies

An Interesting Case and Literature Review of a Coronary Stent Fracture in a Current Generation Platinum Chromium Everolimus-Eluting Stent

Coronary interventions are the mainstay of treatment for stenotic coronary vascular lesions. New stent designs are constantly being evaluated to improve stent performances and clinical outcomes. Coronary stent fracture is uncommon; however, it is associated with potential major consequences including acute coronary syndrome and the need for repeated target vessel revascularization due to in-stent restenosis or stent thrombosis. We report a case of a 66-year-old man with an extensive cardiac disease history, who presented with intractable angina and was found to have a fracture of a current generation, platinum chromium everolimus-eluting stent (Synergy, Boston Scientific Inc.)

A case of spontaneous coronary artery dissection presenting with acute anterior wall myocardial infarction in a young adult male – an increasingly recognized rare disease

Background: Spontaneous coronary artery dissection (SCAD) is increasingly recognized as an important cause of myocardial infarction and sudden death. Although some correlations have been noted in relation to aetiology, no direct causes have been identified in a large number of patients. Most of the patients are women in peripartum period or of childbearing age, with few if any risk factors for coronary heart disease. In men, however, risk factors for atherosclerosis are more prevalent in cases of SCAD Case report: We report a case of a 43-years-old healthy male, with no known risk factors, who presented with ischemic chest pain and elevated troponin levels. He underwent an emergent percutaneous transluminal coronary angiography which revealed a total occlusion of the left anterior descending artery at its origin with an evidence of spontaneous dissection as the cause of the occlusion, which was subsequently treated with placement of a drug-eluting stent and thrombectomy from the distal occluded portion. This case highlights the importance of including spontaneous coronary artery dissection as a cause of ischemic cardiac insults and illustrates the approach to treatment. Conclusion: Internists should have a low threshold of clinical suspicion for SCAD especially in a young patient with no known risk factors and should know the importance of emergency in management

A Case of Diffuse Alveolar Hemorrhage as a Possible Complication of Bivalirudin Therapy

Rare complication/disease Background: Diffuse alveolar hemorrhage (DAH) is a rare but potentially fatal complication of anticoagulant or antiplatelet therapy. Bivalirudin is a specific and reversible direct thrombin inhibitor (DTI). Case Report: We report a case of severe DAH, possibly related to bivalirudin use, in a 61-year-old patient undergoing coronary intervention. The patient had presented with an out-of-hospital cardiac arrest due to acute ST elevation myocardial infarction (STEMI). During the coronary intervention, shortly after receiving bivalirudin, the patient started having frank bleeding from the endotracheal tube and developed hemodynamic compromise. Despite aggressive intervention and intensive care, the patient died. Conclusions: At this time, to our knowledge, there have been no reports of DAH associated with the use of bivalirudin