Comparative computational study of mechanical behavior in self-expanding femoropopliteal stents

The use of the stent to treat peripheral artery disease (PAD) is increased and the proportion of failures also increases. The femoropopliteal artery (FPA) experiences a high deformation ratio compared to the cardiovascular artery due to limp flexion and daily activities that could lead to stent failure, as well as increasing the number of observed mortality and morbidity. In the present work, two of the common PAD stent design models represented as STENT I and STENT II were analyzed by using of finite element method (FEM) to simulate the most mechanical loading modes that could occur in FPA, such as axial tension and compression, torsion, three-point bending and radial compression to give a good understanding of deformation that affected stent inside the in-vivo. The gradual force load was used to simulate all modes, the force values are 0.25 N, 0.5 N, 1.5 N, 2.5 N, 3.5 N and 5.5 N until the stent models obtain the yield-point. The comparison of stent models (STENT I, STENT II) was performed in terms of graphs of total deformation, force-stress and stress-strain for all test modes. The similarity ratio of the total deformation in axial tension and the compression mode for STENT I and STENT II was 17% and that may indicate that STENT I obtained a high deformation value instead of STENT II, while, the torsion similarity ratio was 86% which could show a good agreement in this mode, as well as the similarity ratio, was 78% of the total three-point bending deformation and the value of the similarity ratio in the radial compression mode was 23%. Still unclear what is the clinical mode of mechanical deformation that is more important than others with changing the length of the lesion and stent diameter, and the fatigue life test provides a better understanding of the mechanical tests that must be sought

Güney Marmara Şartlarında Organik Koyun Yetiştiriciliği ve Kuzu Besisi Üzerine Bir Araştırma

Bu araştırma, Marmara Hayvancılık Araştırma Enstitüsü’nde organik ve konvansiyonel sistemlerde yetiştirilen Kıvırcık koyunların döl verimi; kuzuların büyüme özellikleri ve besi performansları ile bazı kesim, karkas ve et özelliklerini karşılaştırmak amacıyla düzenlenmiştir. Organik yetiştiricilik Kıvırcık koyunların döl verimini ve kuzuların büyüme özelliklerini olumlu yönde etkilemiş; organik koyunlar konvansiyonellere göre daha yüksek doğum oranına sahip olmuşlardır. Konvansiyonel beside kuzular, konvansiyonel arpaya dayalı karma yemle ad-libitum düzeyde beslenmiş, ayrıca kuzu başına günde 100 g yonca kuru otu verilmiştir. Organik besi grupları merada otlatılmış, barınak içerisinde organik arpaya dayalı karma yemle beslenmişlerdir. Meranın yetersiz olduğu dönemde ise organik arpa hasılı verilmiştir. Denemede ortalama canlı ağırlığı 35 kg’a ulaşan gruplardaki tüm kuzular kesime gönderilmiştir. Organik kuzular, konvansiyonellere göre hedeflenen besi sonu canlı ağırlığa daha kısa sürede ulaşmışlardır. Organik kuzularda besi süresince günlük ortalama canlı ağırlık artışı konvansiyonellere göre daha yüksek olmuştur (P<0.05). Besleme sistemi sırt yağı kalınlığı üzerine etkili olmuş; organik kuzularda sırt yağı kalınlığı konvansiyonelden daha düşük bulunmuştur (P<0.05). Öte yandan, organik üretim özellikle erkek hayvan etlerindeki kolesterol düzeyini düşürmüştür

Neutrophil-Associated Central Nervous System Inflammation in Tuberculous Meningitis Immune Reconstitution Inflammatory Syndrome.

Background. The immunopathogenesis of tuberculosis-associated immune reconstitution inflammatory syndrome (IRIS) remains incompletely understood, and we know of only 1 disease site-specific study of the underlying immunology; we recently showed that Mycobacterium tuberculosis culture positivity and increased neutrophils in the cerebrospinal fluid (CSF) of patients with tuberculous meningitis (TBM) are associated with TBM-IRIS. In this study we investigated inflammatory mediators at the disease site in patients with TBM-IRIS. Methods. We performed lumbar puncture at 3–5 time points in human immunodeficiency virus (HIV)–infected patients with TBM (n = 34), including at TBM diagnosis, at initiation of antiretroviral therapy (ART) (day 14), 14 days after ART initiation, at presentation of TBM-IRIS, and 14 days thereafter. We determined the concentrations of 40 mediators in CSF (33 paired with blood) with Luminex or enzyme-linked immunosorbent assays. Findings were compared between patients who developed TBM-IRIS (n = 16) and those who did not (TBM-non-IRIS; n = 18). Results. At TBM diagnosis and 2 weeks after ART initiation, TBM-IRIS was associated with severe, compartmentalized inflammation in the CSF, with elevated concentrations of cytokines, chemokines, neutrophil-associated mediators, and matrix metalloproteinases, compared with TBM-non-IRIS. Patients with TBM-non-IRIS whose CSF cultures were positive for M. tuberculosis at TBM diagnosis (n = 6) showed inflammatory responses similar to those seen in patients with TBM-IRIS at both time points. However, at 2 weeks after ART initiation, S100A8/A9 was significantly increased in patients with TBM-IRIS, compared with patients with TBM-non-IRIS whose cultures were positive at baseline. Conclusions. A high baseline M. tuberculosis antigen load drives an inflammatory response that manifests clinically as TBM-IRIS in most, but not all, patients with TBM. Neutrophils and their mediators, especially S100A8/A9, are closely associated with the central nervous system inflammation that characterizes TBM-IRIS

Paper and electronic versions of HM-PRO, a novel patient-reported outcome measure for hematology: an equivalence study.

© 2019 Goswami, Oliva, Ionova et al.Aim:To determine measurement equivalence of paper and electronic application of the hematologi-cal malignancy-patient-reported outcome (HM-PRO), a specific measure for the evaluation of patient-reported outcomes in HMs.Patients & methods:Following International Society of Pharmacoeconomicsand Outcomes Research ePRO Good Research Practice Task Force guidelines, a total of 193 adult patientswith different HMs were recruited into a multicenter prospective study. The paper and the electronic ver-sion of the instrument were completed in the outpatient clinics in a randomized crossover design with a30-min time interval to minimize the learning effect. Those who completed the paper version first, com-pleted the electronic version after 30 min and vice versa. Instrument version and order effects were testedon total score of the two parts of the HM-PRO (Part A: quality of life and Part B: signs & symptoms) in atwo-way ANOVA with patients as random effects. Intraclass correlation coefficients (95% CI) and Spear-man’s rank correlation coefficients were used to evaluate test–retest reliability and reproducibility. Theeffects of instrument version and order were tested on total score of the two parts of HM-PRO.Results:The questionnaire version and administration order effects were not significant at the 5% level. Therewere no interactions found between these two factors for HM-PRO (Part A [quality of life]; p=0.95); and(part B [signs and symptoms]; p=0.72]. Spearman’s rank correlation coefficients were greater than 0.9, andintraclass correlation coefficients ranged from 0.94 to 0.98; furthermore, the scores were not statisticallydifferent between the two versions, showing acceptable reliability indexes. Noteworthy, the differencebetween the completion time for both paper (mean=6:38 min) and electronic version (mean=7:29 min)was not statistically significant (n=100; p=0.11). Patients did not report any difficulty in completing theelectronic version during cognitive interviews and were able to understand and respond spontaneously.Conclusion:Measurement equivalence has been demonstrated for the paper and electronic applicationof the HM-PRO.Peer reviewe

Automatic alignment of surgical videos using kinematic data

Over the past one hundred years, the classic teaching methodology of "see one, do one, teach one" has governed the surgical education systems worldwide. With the advent of Operation Room 2.0, recording video, kinematic and many other types of data during the surgery became an easy task, thus allowing artificial intelligence systems to be deployed and used in surgical and medical practice. Recently, surgical videos has been shown to provide a structure for peer coaching enabling novice trainees to learn from experienced surgeons by replaying those videos. However, the high inter-operator variability in surgical gesture duration and execution renders learning from comparing novice to expert surgical videos a very difficult task. In this paper, we propose a novel technique to align multiple videos based on the alignment of their corresponding kinematic multivariate time series data. By leveraging the Dynamic Time Warping measure, our algorithm synchronizes a set of videos in order to show the same gesture being performed at different speed. We believe that the proposed approach is a valuable addition to the existing learning tools for surgery.Comment: Accepted at AIME 201

Influence of the initial chemical conditions on the rational design of silica particles

The influence of the water content in the initial composition on the size of silica particles produced using the Stöber process is well known. We have shown that there are three morphological regimes defined by compositional boundaries. At low water levels (below stoichiometric ratio of water:tetraethoxysilane), very high surface area and aggregated structures are formed; at high water content (>40 wt%) similar structures are also seen. Between these two boundary conditions, discrete particles are formed whose size are dictated by the water content. Within the compositional regime that enables the classical Stöber silica, the structural evolution shows a more rapid attainment of final particle size than the rate of formation of silica supporting the monomer addition hypothesis. The clearer understanding of the role of the initial composition on the output of this synthesis method will be of considerable use for the establishment of reliable reproducible silica production for future industrial adoption

Impact of Vitamin D Supplementation on Arterial Vasomotion, Stiffness and Endothelial Biomarkers in Chronic Kidney Disease Patients

Background: Cardiovascular events are frequent and vascular endothelial function is abnormal in patients with chronic kidney disease (CKD). We demonstrated endothelial dysfunction with vitamin D deficiency in CKD patients; however the impact of cholecalciferol supplementation on vascular stiffness and vasomotor function, endothelial and bone biomarkers in CKD patients with low 25-hydroxy vitamin D [25(OH)D] is unknown, which this study investigated. Methods: We assessed non-diabetic patients with CKD stage 3/4, age 17–80 years and serum 25(OH)D ,75 nmol/L. Brachial artery Flow Mediated Dilation (FMD), Pulse Wave Velocity (PWV), Augmentation Index (AI) and circulating blood biomarkers were evaluated at baseline and at 16 weeks. Oral 300,000 units cholecalciferol was administered at baseline and 8-weeks. Results: Clinical characteristics of 26 patients were: age 50614 (mean61SD) years, eGFR 41611 ml/min/1.73 m2, males 73%, dyslipidaemia 36%, smokers 23% and hypertensives 87%. At 16-week serum 25(OH)D and calcium increased (43616 to 84629 nmol/L, p,0.001 and 2.3760.09 to 2.4260.09 mmol/L; p = 0.004, respectively) and parathyroid hormone decreased (10.868.6 to 7.464.4; p = 0.001). FMD improved from 3.163.3% to 6.163.7%, p = 0.001. Endothelial biomarker concentrations decreased: E-Selectin from 566662123 to 525662058 pg/mL; p = 0.032, ICAM-1, 3.4560.01 to 3.1061.04 ng/mL; p = 0.038 and VCAM-1, 54633 to 42633 ng/mL; p = 0.006. eGFR, BP, PWV, AI, hsCRP, von Willebrand factor and Fibroblast Growth Factor-23, remained unchanged. Conclusion: This study demonstrates for the first time improvement of endothelial vasomotor and secretory functions with vitamin D in CKD patients without significant adverse effects on arterial stiffness, serum calcium or FGF-23. Trial Registration: ClinicalTrials.gov NCT0200571

Resistance to ondansetron: Role of pharmacogenetics in post-operative nausea and vomiting

Post-operative nausea and vomiting is the most annoying and at the same time a dangerous side effect of general anaesthesia. Ondansetron is a routinely used anti emetic drug which is being administered by the trial and error principle. Though it did revolutionized the management of this condition but by and large failed to completely eliminate the problem. Recently an important factor possibly elucidating this failure is said to be the differing expression of genes controlling proteins that are involved in transport and receptors related to this drug. Quite surprisingly these transporter and receptor pathways have been found to be polymorphic and at the same time shown to be related to efficacy of the drug. The differentiation between those responding to treatment and those not responding may pave a way to individualize treatment for emesis to a greater extent. This review highlights the pharmacogenetics related to this commonly used anti-emetic drug in anaesthesia. It is visualized as a promising way to achieve the target of individualized therapy. It seems obvious that pharmacogenetics will become an important field of anaesthesia research in the future.Keywords: 5-Hydroxytryptamine type 3 receptor antagonists; Ondansetron; Post-operative nausea and vomiting; Polymorphism; Pharmacogenetic

Effect of Fly Ash Fraction and Mixing Process Variables On Mechanical Properties of Polymer Composites

The development of material technology continues to be carried out to meet the needs of engineering materials which are increasing day by day and are environmentally friendly or green. In this study, the process of making epoxy resin composites with fly ash was carried out from the combustion process of a power plant. This study aims to determine the strength of the mechanical properties between the epoxy resin and fly ash weight fraction by stirring treatment in the mixing process using tensile, flexural, and impact tests, microscopic examination, FTIR, and X-RD analysis. The treatments were mixing epoxy resin and fly ash with a weight fraction of 10%, 20%, and 30%, stirring speeds of 100 rpm, 150 rpm, and 200 rpm, for 10 minutes, 20 minutes, and 30 minutes. The results showed that the F2S3T3 composite had a greater tensile strength of 31,94 MPa, while the other composites had a tensile strength above 22-30 MPa, and the lowest was 13,07 MPa in the F1S2T3 composite. The maximum modulus of elasticity is found in the F3S3T1 composite with a value of 11,12 MPa, and the lowest is found in the F1S2T3 composite at 2,06 MPa. The F3S2T2 composite has a maximum flexural strength of 33,32 MPa, and the lowest composite F2S2T1 is 17,40 MPa with a flexural modulus of 270,41 MPa. The maximum flexural modulus in the F1S1T1 composite with a value of 382,76 MPa with a flexural strength value of 28,82 MPa. The F2S1T2 composite has an impact energy of 6,94 Joules with an impact strength of 203,47 MPa, and there are 2 composites that have the same impact energy value of 5,20 Joules, namely F3S2T2, and F3S1T3. From SEM observations, the fracture surface of the composite has a concave and prominent surface, but a lot of dust is trapped so it affects the bond in the matrix and reinforcement