Effect of the arterial needle bevel position on puncture pain and postremoval bleeding time in hemodialysis patients: A self-controlled, single-blind study

Aim: This study aimed to investigate the effect of the bevel orientation (facing upwards or downwards towards the skin) of the needle inserted into the arterial limb of the arteriovenous fistula (AVF) on puncture pain and postremoval bleeding time. Methods: This study, using a single-blind crossover design, was conducted on 35 maintenance hemodialysis patients who had been dialyzed for at least 6 months and in whom blood access was via an AVF. AVF cannulation was performed with the needle bevel pointing upward in the first six sessions and the needle bevel pointing downwards (towards the skin) in the subsequent six sessions. Needles were always inserted in the direction of blood flow. At each dialysis session, cannulation pain was measured using a visual analog scale (VAS), and the bleeding time at the end of dialysis after needle removal was recorded. Findings: The VAS score and postremoval bleeding time were lower when the needle bevel pointed downwards towards the skin during insertion (P < 0.05). Discussion: Insertion of the needle with the bevel pointed downward decreased puncture pain during cannulation and bleeding time postdialysis on needle removal. © 2022 International Society for Hemodialysis

RF-MEMS teknolojisi ile faz dizili anten yapımı

TÜBİTAK EEEAG Proje30.06.201

Molecular etiology of arthrogryposis in multiple families of mostly Turkish origin

BACKGROUND. Arthrogryposis, defined as congenital, joint contractures in 2 or more body areas, is a clinical sign rather than a specific disease diagnosis. To date, more than 400 different disorders have been described that present with arthrogryposis, and variants of more than 220 genes have been associated with these disorders; however, the underlying molecular etiology remains unknown in the considerable majority of these cases. METHODS. We performed whole exome sequencing (WES) of 52 patients with clinical presentation of arthrogryposis from 48 different families. RESULTS. Affected individuals from 17 families (35.4%) had variants in known arthrogryposis-associated genes, including homozygous variants of cholinergic gamma nicotinic receptor (CHRNG, 6 subjects) and endothelin converting enzyme-like 1 (ECELI, 4 subjects). Deleterious variants in candidate arthrogryposis-causing genes (fibrillin 3 [FBN3], myosin IXA [MY09A], and pleckstrin and Sec7 domain containing 3 [PSD3]) were identified in 3 families (6.2%). Moreover, in 8 families with a homozygous mutation in an arthrogryposis-associated gene, we identified a second locus with either a homozygous or compound heterozygous variant in a candidate gene (myosin binding protein C, fast type (MYBPC2] and vacuolar protein sorting 8 [VPS8], 2 families, 4.2%) or in another disease-associated genes (6 families, 12.5%), indicating a potential mutational burden contributing to disease expression. CONCLUSION. In 58.3% of families, the arthrogryposis manifestation could be explained by a molecular diagnosis; however, the molecular etiology in subjects from 20 families remained unsolved by WES. Only 5 of these 20 unrelated subjects had a clinical presentation consistent with amyoplasia; a phenotype not thought to be of genetic origin. Our results indicate that increased use of genome-wide technologies will provide opportunities to better understand genetic models for diseases and molecular mechanisms of genetically heterogeneous disorders, such as arthrogryposis. FUNDING. This work was supported in part by US National Human Genome Research Institute (NHGRI)/National Heart, Lung, and Blood Institute (NHLBI) grant U54HG006542 to the Baylor-Hopkins Center for Mendelian Genomics, and US National Institute of Neurological Disorders and Stroke (NINDS) grant RO1NS058529 to J.R. Lupski.US NHGRI/NHLBI [U54HG006542]; US NINDSUnited States Department of Health & Human ServicesNational Institutes of Health (NIH) - USANIH National Institute of Neurological Disorders & Stroke (NINDS) [R01NS058529]; CPRIT training Program [RP140102]; Medical Genetics Research Fellowship Program [T32 GM07526]; NATIONAL HUMAN GENOME RESEARCH INSTITUTEUnited States Department of Health & Human ServicesNational Institutes of Health (NIH) - USANIH National Human Genome Research Institute (NHGRI) [U54HG006542] Funding Source: NIH RePORTER; NATIONAL INSTITUTE OF GENERAL MEDICAL SCIENCESUnited States Department of Health & Human ServicesNational Institutes of Health (NIH) - USANIH National Institute of General Medical Sciences (NIGMS) [T32GM007526] Funding Source: NIH RePORTER; NATIONAL INSTITUTE OF NEUROLOGICAL DISORDERS AND STROKEUnited States Department of Health & Human ServicesNational Institutes of Health (NIH) - USANIH National Institute of Neurological Disorders & Stroke (NINDS) [R01NS058529] Funding Source: NIH RePORTERWe thank the patients and their families who participated in this study. This work was supported in part by US NHGRI/NHLBI grant U54HG006542 to the Baylor-Hopkins Center for Mendelian Genomics and US NINDS grant R01NS058529 to J.R. Lupski. W.L. Charng is supported by CPRIT training Program RP140102, and T. Harel is supported by the T32 GM07526 Medical Genetics Research Fellowship Program

Bilgi toplumu teknolojileri için anten sistemleri ve algılayıcılar

TÜBİTAK EEEAG01.10.2010Bu proje kapsamında, özellikle milimetre-dalga frekanslarında çalışan yeniden şekillendirilebilir anten, elektronik taramalı dizi anten ve yansıtıcı dizi anten tasarımı, üretimi ve ölçümleri yapılmıştır. Yeniden şekillendirilebilirlik özelliği için farklı teknolojiler kullanılmıştır. Huzmesi yönlendirilebilen sur biçimli mikroşerit yürüyen dalga anten dizisi X-bant uygulamalarında kullanılmak üzere tasarlamış, üretilmiş ve ölçülmüştür. Antenin ana huzmesinin istenilen yöne elektronik olarak döndürülebilmesini sağlayabilmek için mikroşerit hat üzerinde gerekli faz değişimini sağlayacak varaktör diyotlar kullanılmıştır. Yapılan EM benzetim ve ölçümler sonucu sur biçimli anten dizisinde, ana huzmenin diyot kontrolü ile tasarlandığı gibi 10 lik bir açı taraması yapabildiği gösterilmiştir. Bu kavram kanıtlaması şeklinde bir çalışmadır; huzmenin daha büyük açı aralığında tarama yapması için tasarımda yapılması gereken değişiklikler belirtilmiştir. MM-Dalga sabit genişlikli ve doğrusal sönümlenen yarık antenler tasarlanıp, üretilmiş ve antenin şeklinin, optik uyarımla bu iki yapı arasında değiştirilmesinin sağlanması durumunda ışıma örüntüsünün değiştirilebileceği gösterilmiştir. Proje kapsamında gerçekleştirilen bir diğer çalışmada da K ve Ka bantlarında bağımsız çalışabilen, RF MEMS anahtarlarla huzmesi elektronik olarak döndürülebilen dairesel polarizasyonlu yansıtıcı dizi anten tasarlanmış, üretilmiş ve ölçülmüştür. Çift frekanslı (24.4 GHz ve 35.5 GHz) dizi iç içe geçmiş farklı boyutlarda iki ayrık-halka dizisi şeklinde tasarlanmıştır. Huzme döndürme amacıyla her bir ayrık halkanın açısal konumunu RF MEMS anahtarlarla ayarlayarak, dairesel polarizasyonlu dalgaların fazları kontrol edilmektedir. Anten ODTÜ MEMS merkezinde geliştirilen yüzey mikro-işleme süreciyle üretilmiştir. Işıma örüntüleri ölçülmüş ve benzetim sonuçlarıyla karşılaştırılmıştır. Ölçümlerle, ana huzmenin, tasarlandığı gibi, Ka bandında 35°‟ye, K bandında 24°‟ye döndürülebildiği gösterilmiştir. Proje çalışmalarından sur biçimli mikroşerit anten dizisiyle ilgili hazırlanan makale Microwave and Optical Technology Letters adlı dergide yayınlanmak üzere kabul edilmiştir. Yansıtıcı dizi antenle ilgili makale de hazırlık sürecindedir. Saygın konferanslarda yedi bildiri sunulmuştur. Ayrıca, proje kapsamında üç yüksek lisans tez çalışması tamamlanmıştır.In this project, reconfigurable antenna, beam steering array and reflectarray have been designed, produced and measured, especially in mm-wave frequencies. To provide reconfigurability, different technologies have been considered. X-band electronically scanning meanderline microstrip traveling wave antenna array has been designed, produced and measured. To rotate the antenna beam to the desired direction, microstrip meander line has been loaded by varactor diodes that provide required phase shift values. EM simulations and rdiation pattern measurements of the meanderline antenna have demonstrated that the antenna has the capability to scan 10 with the control of varactors as designed. This is a proof-of-concept type study; alternative configurations to increase the scan range have also been discussed. MM-wave tapered slot antennas with a constant width and linear taper have been designed, produced and measured. It has been demonstrated that if the shape of the tapered slot antenna can be changed between constant width and linear taper structures by means of optical excitation, radiation pattern reconfigurability can be obtained. In another study accomplished in this project, electronically scanning circularly polarized reflectarray working independently in K and Ka bands has been designed, produced and measured. Dual band (24.4 GHz and 35.5 GHz) reflectarray has been designed as an interlaced array of split rings of two different sizes. In order to steer the beam, the phase of the incident circularly polarized wave is controlled by RF MEMS switches that modify the angular orientation of split-rings individually. The antenna has fabricated by using surface micromachining process developed in METU MEMS Center. Radiation patterns of the antenna are measured and compared with the simulations. It has been shown that the reflectarray is capable of beam switching to 35° in Ka band, 24° in K band as required. One journal paper on meanderline antenna has been accepted to be published in Microwave and Optical Technology Letters. Preparation of manuscript on reflectarray is under progress. Seven conference papers have been presented in well known Conferences. Furthermore, three Master Thesis studies have been accomplished during the project