Use of bioresorbable vascular scaffold : a meta-analysis of patients with coronary artery disease

BACKGROUND: Differences in outcomes between bioresorbable vascular scaffold (BVS) systems and drug-eluting metal stents (DES) have not been fully evaluated. We aimed to compare clinical and angiographic outcomes in randomised studies of patients with coronary artery disease (CAD), with a secondary analysis performed among registry studies. METHODS: A meta-analysis comparing outcomes between BVS and DES in patients with CAD. Overall estimates of treatment effect were calculated with random-effects model and fixed-effects model. RESULTS: In 6 randomised trials (3818 patients), BVS increased the risk of subacute stent thrombosis (ST) over and above DES (OR 2.14; CI 1.01 to 4.53; p=0.05), with a trend towards an increase in the risk of myocardial infarction (MI) (125 events in those assigned to BVS and 50 to DES; OR 1.36; CI 0.97 to 1.91; p=0.07). The risk of in-device late lumen loss (LLL) was higher with BVS than DES (mean difference 0.08 mm; CI 0.03 to 0.13; p=0.004). There was no difference in the risk of death or target vessel revascularisation (TVR) between the two devices. In 6 registry studies (1845 patients), there was no difference in the risk of death, MI, TVR or subacute ST between the two stents. Final BVS dilation pressures were higher in registry than in randomised studies (18.7±4.6 vs 15.2±3.3 atm; p<0.001). CONCLUSIONS: Patients treated with BVS had an increased risk of subacute ST and slightly higher LLL compared with those with DES, but this might be related to inadequate implantation techniques, in particular device underexpansion.Peer reviewedFinal Published versio

Adsorption and Microfiltration Processes to Treat Dye and Coffee Wastewater.

Wastewater from coffee processing industry creates high biological and chemical oxygen demand in the surface water. In addition to coffee wastewater from coffee industry, dyes from textile industry enter surface water affecting water quality in terms of transmissivity of light. Adsorption is an economical wastewater treatment process to remove color from dye and coffee wastewater. In the current thesis, adsorption using low-cost adsorbents like peanut hull and onion peel are used to treat combined dye and coffee wastewater. Three representative dyes including acid black 48, disperse yellow 3, crystal violet certified with processed coffee is used in preparing batch adsorption samples. Using UV-Vis Spectrophotometer, absorbance and transmittance of the wastewater samples are measured. After adsorbents reach adsorption capacity, the suspended solids are removed using Whatman 41 microfilters. To understand the change in organic carbon before and after treatment in the wastewater, NPOC (Non-Purgeable Organic Carbon) is compared using Shimadzu TOC analyzer. This thesis focuses on the two-stage treatment process of adsorption and microfiltration in a binary mixture of dye and coffee wastewater. Increasing Adsorbent dosage in the representative wastewater samples gives us the idea of optimum dosage required in the treatment process. The comparative study of adsorbent dosage with transmittance and NPOC gives us an understanding of the efficiency of low-cost adsorbents when compared to Powdered Activated Carbon

Type-1 and type-2 fuzzy logic-based space vector modulation for two-level inverter fed induction motor

Two-level inverter control with type-1 and type-2 fuzzy logic-based space vector pulse-width modulation (PWM) method for induction motor drive (IMD) is presented in this paper. A new sampling time independent strategy with type-1 and type-2 fuzzy based methods are used in generating three phase duty ratios which are directly obtained without mathematical equations. The conventional method of space vector modulation (SVM) produces the duty ratios for the inverter which are sampling time dependent. However, in type-1 and type-2 fuzzy based space vector PWM algorithms, the three phases duty ratios generated are sampling time independent and with a new integrated dead-time insertion in SVM itself, can be implemented practically for any switching frequency. As the rule-base for Mamdani non-singleton interval type-1 and type-2 fuzzy inference systems are designed manually, with the expert knowledge of conventional space vector PWM, the duty ratios of the inverter are generated such that the performance of the IMD is improved. The simulation studies for aforementioned cases is performed in matrix laboratory (MATLAB) and experimental validation for the proposed space vector PWM algorithms is validated using real-time sacraetheologiae magister (STM) hardware with STM32F429I Cortex M4 processor for a 1 hp IMD

Coronary artery endothelial dysfunction is positively correlated with low density lipoprotein and inversely correlated with high density lipoprotein subclass particles measured by nuclear magnetic resonance spectroscopy.

OBJECTIVE: The association between cholesterol and endothelial dysfunction remains controversial. We tested the hypothesis that lipoprotein subclasses are associated with coronary endothelial dysfunction. METHODS AND RESULTS: Coronary endothelial function was assessed in 490 patients between November 1993 and February 2007. Fasting lipids and nuclear magnetic resonance (NMR) lipoprotein particle subclasses were measured. There were 325 females and 165 males with a mean age of 49.8+/-11.6 years. Coronary endothelial dysfunction (epicardial constriction>20% or increase in coronary blood flow<50% in response to intracoronary acetylcholine) was diagnosed in 273 patients, the majority of whom (64.5%) had microvascular dysfunction. Total cholesterol and LDL-C (low density lipoprotein cholesterol) were not associated with endothelial dysfunction. One-way analysis and multivariate methods adjusting for age, gender, diabetes, hypertension and lipid-lowering agent use were used to determine the correlation between lipoprotein subclasses and coronary endothelial dysfunction. Epicardial endothelial dysfunction was significantly correlated with total (p=0.03) and small LDLp (LDL particles) (p<0.01) and inversely correlated with total and large HDLp (high density lipoprotein particles) (p<0.01). CONCLUSIONS: Epicardial, but not microvascular, coronary endothelial dysfunction was associated directly with LDL particles and inversely with HDL particles, suggesting location-dependent impact of lipoprotein particles on the coronary circulation

Utilization of Agro-based Adsorbents in Binary Wastewater Treatment

The application of agro-based adsorbents is growing in the tertiary stage of the wastewater treatment process during the presence of hazardous pollutants. Dye and coffee industries are among the major wastewater pollutant sources negatively affect aquatic ecosystems and human health. The current study attempts to treat a binary mixture of crystal violet (CV) and coffee wastewater using agro-based adsorbents such as peanut hull and onion peel. The performance and efficacy of low-cost adsorbents were evaluated using parameters, including transmittance and non-purgeable organic carbon (NPOC). Batch adsorption studies were conducted to optimize both the adsorbent size and dosage that affect the treatment process. The experimental data obtained from the experiment were analyzed to understand whether Langmuir or Freundlich best fits the treatment process\u27s experimental data. It was observed that Langmuir isotherm seems to fit experimental data using peanut hull and Freundlich isotherm using onion peel. The kinetics of the adsorption process appears to follow the pseudo-first-order kinetic model. The regression coefficient value of onion peel was 0.91, and uptake was 58.14 mg/g. Similarly, using the peanut hull, the regression coefficient was 0.99, and uptake was 57.47 mg/g. It seems that peanut hull appears to perform better as a low-cost adsorbent compared to onion peel. The adsorption capacity increased with the increasing dosage of low-cost adsorbent (peanut hull) until the adsorbent size of 0.6-0.425 mm and steadily decreased after that

Malignant Arrhythmia in Apical Ballooning Syndrome: Risk Factors and Outcomes

Objectives: We sought to determine the frequency and outcomes with symptomatic arrhythmia in patients with apical ballooning syndrome (ABS). Methods: A retrospective review of the Mayo Clinic Angiography database was conducted to identify patients who met the Mayo criteria for ABS. Patients with documented arrhythmias formed the study group, and 31 randomly selected patients with ABS but without arrhythmia formed the control group. Results: Out of 105 patients identified with ABS, 6 (5.7%) women aged 69 +/- 9 years experienced significant arrhythmia (ventricular fibrillation, asystole), 2 patients died, and 1 required permanent pacemaker implantation. When compared with controls, the study group showed no significant difference with respect to ECG characteristics (QT, QRS duration or axis) except for R-R interval variability (see comments below) (30.6±6 vs 14.5±17 p = 0.0004), QTc, and P-R interval. Patients without arrhythmia were more likely to be on beta-blocker therapy than the study population (33% vs 80.6% p = 0.02). Conclusion: Life-threatening arrhythmia is uncommon (5.7%) with ABS despite marked, structural abnormalities. When arrhythmias do occur, the outcome is poor. Prominent variability in R-R intervals appears to be predictive of significant arrhythmias in ABS. The role of beta-blocker therapy in preventing arrhythmia with ABS requires further investigation

The Detection Rate of Late Gadolinium Enhancement in Takotsubo Syndrome: A Systematic Review and Meta-Analysis

Absence of late gadolinium enhancement (LGE) on cardiac magnetic resonance (CMR) is commonly used to distinguish takotsubo syndrome (TTS) from other myocardial diseases. However, case series have reported the presence of LGE in TTS. The present study aimed to summarize the evidence on the frequency of LGE in TTS and identify potential variables that may influence the detection of LGE. Electronic databases were systematically searched for studies reporting LGE frequency in TTS patients. The overall frequency was estimated using the inverse variance method and a random-effect model for single proportion. Factors influencing LGE detection were analyzed. Among 490 studies screened, 21 were included (703 patients, 90% female). The estimated overall frequency of LGE was 22.4% (95% CI 8.7-39.6%). Among TTS patients who underwent CMR within three days of symptom occurrence, the frequency of LGE was 40.7% (95% CI 18.8-64.5%), significantly higher than among those who performed CMR after three days (3.9%, p&lt;0.010). The sensitivity threshold used in the imaging protocols had a statistically significant impact on the frequency of LGE detection (p=0.030). Ten studies performed a follow-up CMR after at least three months, reporting a frequency of LGE of 1.7 % (95% CI 0.0-8.9%). In conclusion, published studies report the presence of LGE in TTS at presentation among a significant proportion of patients. However, its detection is strongly influenced by the duration between symptom onset and CMR acquisition, and by the sensitivity threshold used for the imaging protocol. LGE is rarely present at follow-up