Delay-Reliability Trade-off in MIMO-Enabled IEEE 802.11-Based Wireless Sensor and Actuator Networks

AbstractOne of the main challenges in Wireless Sensor and Actuator Networks (WSAN) is the delay caused by shared and nondeterministic behavior of wireless communication medium. The Retry-Limit parameter of IEEE 802.11 standard can be used to control packet reliability, whereas other parameters mostly effect on the packet delay. In this paper, at first the delay-reliability trade-off in WSANs based on MIMO-Enabled IEEE 802.11 standard, utilizing Enhanced Distributed Channel Access (EDCA) at Medium Access Control (MAC) layer and Maximum Likelihood Spatial Multiplexing at PHYsical (PHY) Layer is studied. Then two simple adaptive schemes have been proposed to minimize packet delay while satisfying the required reliability at noisy factory environment

Association of human platelet alloantigens encoding gene polymorphisms with the risk of Coronary artery disease in Iranian patients

Background: Coronary artery disease (CAD) is characterized by narrowing/ blockade of coronary arteries that is mainly caused by atherosclerotic plaques. Considering the involvement of platelet abnormalities, such as defective aggregation and adhesion, in the cardiovascular-related disorders, genetic variations in human platelet alloantigens (HPA) have been implicated in the CAD susceptibility. Herein, we intended to determine the association of HPA-1 to -6, -9, and -15 biallelic polymorphisms with CAD in an Iranian population. Methods: In this retrospective case�control study, 200 CAD subjects and 100 matched healthy individuals were enrolled. DNA samples were isolated from peripheral blood samples and genotyping of HPA polymorphisms was accomplished using polymerase chain reaction-sequence-specific primers. Results: The alleles and genotypes of studied HPA polymorphisms were equally distributed among cases and controls and therefore no statistically significant differences were detected. Univariate analysis identified no association of combined haplotypes with CAD risk. However, multivariate analysis showed a positive association of the� HPA1b/2a/3b haplotype with CAD after adjustment for some covariates (including BMI, TG, LDL, FBS and blood pressure) that conferred a CAD susceptibility haplotype (P = 0.015; OR = 2.792; 95 CI 1.45�8.59). Conclusions: Although alleles, genotypes, and haplotypes of HPA polymorphisms were not associated with CAD risk, HPA1b/2a/3b haplotype was found to be a dependent disease risk haplotype in Iranian population after correcting for confounding factors. © 2021, The Author(s)

Two Challenging Cases with COVID heart

COVID-19 affects the heart through various pathways. It can increase thrombotic complications that ultimately lead to myocardial infarction even in patients without a history of underlying heart disease. © 2020 The Authors. Clinical Case Reports published by John Wiley & Sons Lt

Acute myocardial infarction following blunt chest trauma and coronary artery dissection

Blunt chest traumatic coronary artery dissection is an uncommon cause of atherosclerotic and non-atherosclerotic Acute Myocardial Infarction (AMI). Injuries of the coronary artery after blunt chest trauma are caused by different mechanisms such as vascular spasm, dissection and intimal tear or rupture of an existing thrombus formation. Chest pain might be masked by other injuries in patients with multiple traumas in car accident. Present case report is on a 37-year-old male without any specific past medical history who reported to the emergency department of a hospital with chest discomfort and was discharged with the impression of chest wall pain. After three days he experienced severe chest pain and he was admitted with the impression of acute coronary syndrome and underwent coronary angiography which showed Left Anterior Descending (LAD) artery dissection. The possibility of injury of the coronary artery should be kept in mind after blunt trauma to the chest. This condition is sometimes underdiagnosed. Its diagnosis may be difficult because chest pain can be interpreted as being secondary to chest wall contusion or it may be overshadowed by other injuries. Coronary dissection diagnosis after chest trauma requires clinical suspicion and systematic evaluation. Electrocardiography (ECG) should be done for every patient with thoracic trauma as the clinical findings may be misleading. © 2016, Journal of Clinical and Diagnostic Research. All rights reserved

In-hospital and six-month outcomes of elderly patients undergoing primary percutaneous coronary intervention for acute st-elevation myocardial infarction

BACKGROUND: Elderly patients constitute a rapidly growing proportion of the population, and hence the increasing rises in the number of patients with ST-segment-elevation myocardial infarction (STEMI). Primary percutaneous coronary intervention (PCI), which is now established as the preferred reperfusion strategy in STEMI patients, has been inadequately investigated in this high-risk group. The aim of the present study was to investigate the in- hospital and 6-month outcomes of primary PCI in elderly patients (� 75 years) with STEMI. METHODS: A total of 100 elderly patients with STEMI including those with cardiogenic shock were included. Primary PCI procedures were performed in a tertiary referral center between 2009 and 2014. In-hospital and 6-month outcomes of patients were recorded and analyzed. RESULTS: The average age of the patients was 79.6 ± 3.8 years (range = 75-90 years) and 27.0 were women. Cardiovascular risk factors and prior events were common. Nearly, half of the patients had three-vessel disease and the left anterior descending artery (LAD) was the most common infarct-related artery. The presence of cardiogenic shock but not the other variables was associated with less anatomic and procedural success (P < 0.001). It was also the major independent predictors of 6-month mortality in the patients aged � 75 years, hazard ratio (HR) = 8.02; 95% confidence interval (CI): 1.75-25.97, P < 0.001. In-hospital mortality was 2.4% in the patients without and 83.0% in those with cardiogenic shock. CONCLUSION: Primary PCI in aged patients could be associated with low complication rates and improved survival if performed in high-volume centers with experienced operators. Considering the very high rate of mortality in patients with cardiogenic shock, there should be measures to treat these patients before the onset of hemodynamic instability. © 2016, Isfahan University of Medical Sciences(IUMS). All rights reserved

Percutaneous device closure for secundum-type atrial septal defect: Short and intermediate-term results

BACKGROUND: Device closure of an isolated secundum type atrial septal defect (ASD) has been used as an alternative method for open surgical closure with comparable success and lower morbidity. In this study we evaluated the procedural success and mid-term follow-up results of percutaneous closure of secundum ASD with an Amplatzer�Septal Occluder(ASO) device or a Figula ASD occluder device. METHODS: From June 2001 to January 2009, 74 consecutive patients were scheduled for percutaneous device closure in two centers in Tehran, Iran. All patients had a stretched defect diameter of 30mm or less. After using a sizing balloon to measure the stop-flow diameter, device implantation was performed under the guidance of a trans-esophageal echocardiography (TEE).The size was generally 1 - 2 mm larger than the stretched diameter. Patients were followed for an average of 11 ±4 months. RESULTS: The median stretched diameter of the defect was 20.7±4.8 mm (range: 8 - 30 mm).A total of 73 devices were used in this study. Device closure was successful in 72 (97.2) out of 74 patients. Repositioning of the device was required in one patient. Major complications(including significant residual shunt and device embolization) occurred in 3 (4) patients.There was no procedure-related mortality in our patients. Mild-to-moderate residual shunt was detectable in 10 (13.7) patients immediately following the procedure and in 5 (6.7) patients 24 hours after the procedure. None had residual flow across the device at the end of the follow-up period. CONCLUSION: Device closure of ASD has a safety profile comparable to open surgical repair and can effectively close the defect with excellent procedural and mid-term results

Outcomes of chronic total occlusion percutaneous coronary intervention from the RAIAN (RAjaie - Iran) registry

Objective: While most of the evidence in CTO interventions emerge from Western and Japanese studies, few data have been published up today from the Middle East. Objective of this study was to evaluate technical success rates and clinical outcomes of an Iranian population undergoing CTO PCI in a tertiary referral hospital. Moreover, we sought to evaluate the efficacy of our CTO teaching program. Methods: This is a retrospective single-center cohort study including 790 patients who underwent CTO PCI performed by operators with different volumes of CTOs PCI performed per year. According to PCI result, all patients have been divided into successful (n&nbsp;=&nbsp;555, 70.3&nbsp;%) and unsuccessful (n&nbsp;=&nbsp;235, 29.7&nbsp;%) groups. Study endpoints were Major Adverse Cardiovascular Events and Health Status Improvement evaluated using the Seattle Angina Questionnaire at one year. Results: A global success rate of 70&nbsp;% for antegrade and 80&nbsp;% for retrograde approach was shown despite the lack of some CTO-dedicated devices. During the enrollment period, the success rate increased significantly among operators with a lower number of CTO procedures per year. One-year MACE rate was similar in both successful and unsuccessful groups (13.5&nbsp;% in successful and 10.6&nbsp;% in unsuccessful group, p&nbsp;=&nbsp;0.173). One year patients' health status improved significantly only in successful group. Conclusions: No significant differences of in-hospital and one-year MACE were found between the successful and unsuccessful groups. Angina symptoms and quality of life significantly improved after successful CTO PCI. The RAIAN registry confirmed the importance of operator expertise for CTO PCI success

Large scale variation in Enterococcus faecalis illustrated by the genome analysis of strain OG1RF

A comparison of two strains of the hospital pathogen Enterococcus faecalis suggests that mediators of virulence differ between strains and that virulence does not depend on mobile gene element

Photodynamic and Antibiotic Therapy Impair the Pathogenesis of Enterococcus faecium in a Whole Animal Insect Model

Enterococcus faecium has emerged as one of the most important pathogens in healthcare-associated infections worldwide due to its intrinsic and acquired resistance to many antibiotics, including vancomycin. Antimicrobial photodynamic therapy (aPDT) is an alternative therapeutic platform that is currently under investigation for the control and treatment of infections. PDT is based on the use of photoactive dye molecules, widely known as photosensitizer (PS). PS, upon irradiation with visible light, produces reactive oxygen species that can destroy lipids and proteins causing cell death. We employed Galleria mellonella (the greater wax moth) caterpillar fatally infected with E. faecium to develop an invertebrate host model system that can be used to study the antimicrobial PDT (alone or combined with antibiotics). In the establishment of infection by E. faecium in G. mellonella, we found that the G. mellonella death rate was dependent on the number of bacterial cells injected into the insect hemocoel and all E. faecium strains tested were capable of infecting and killing G. mellonella. Antibiotic treatment with ampicillin, gentamicin or the combination of ampicillin and gentamicin prolonged caterpillar survival infected by E. faecium (P = 0.0003, P = 0.0001 and P = 0.0001, respectively). In the study of antimicrobial PDT, we verified that methylene blue (MB) injected into the insect followed by whole body illumination prolonged the caterpillar survival (P = 0.0192). Interestingly, combination therapy of larvae infected with vancomycin-resistant E. faecium, with antimicrobial PDT followed by vancomycin, significantly prolonged the survival of the caterpillars when compared to either antimicrobial PDT (P = 0.0095) or vancomycin treatment alone (P = 0.0025), suggesting that the aPDT made the vancomycin resistant E. faecium strain more susceptible to vancomycin action. In summary, G. mellonella provides an invertebrate model host to study the antimicrobial PDT and to explore combinatorial aPDT-based treatments

Large-Scale Screening of a Targeted Enterococcus faecalis Mutant Library Identifies Envelope Fitness Factors

Spread of antibiotic resistance among bacteria responsible for nosocomial and community-acquired infections urges for novel therapeutic or prophylactic targets and for innovative pathogen-specific antibacterial compounds. Major challenges are posed by opportunistic pathogens belonging to the low GC% Gram-positive bacteria. Among those, Enterococcus faecalis is a leading cause of hospital-acquired infections associated with life-threatening issues and increased hospital costs. To better understand the molecular properties of enterococci that may be required for virulence, and that may explain the emergence of these bacteria in nosocomial infections, we performed the first large-scale functional analysis of E. faecalis V583, the first vancomycin-resistant isolate from a human bloodstream infection. E. faecalis V583 is within the high-risk clonal complex 2 group, which comprises mostly isolates derived from hospital infections worldwide. We conducted broad-range screenings of candidate genes likely involved in host adaptation (e.g., colonization and/or virulence). For this purpose, a library was constructed of targeted insertion mutations in 177 genes encoding putative surface or stress-response factors. Individual mutants were subsequently tested for their i) resistance to oxidative stress, ii) antibiotic resistance, iii) resistance to opsonophagocytosis, iv) adherence to the human colon carcinoma Caco-2 epithelial cells and v) virulence in a surrogate insect model. Our results identified a number of factors that are involved in the interaction between enterococci and their host environments. Their predicted functions highlight the importance of cell envelope glycopolymers in E. faecalis host adaptation. This study provides a valuable genetic database for understanding the steps leading E. faecalis to opportunistic virulence