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Background: Smoking is a well-known related factor for many health problems in a human being through different ways of exposure. Objectives: Thie aim of the study was to examine the effects of different types of cigarette smoking on hemoglobin level, high sensitive C-Reactive Protein (hsCRP), Malondialdehyde (MDA), and IgE levels in healthy adult subjects. Methods: One hundred seventy-one healthy adult females and males were included in this study. They divided into four groups: cigarette, shisha, passive smokers, and non-smokers groups. Serum samples from all groups analyzed for hemoglobin, hsCRP, IgE, and malondialdehyde level. Results: The mean MDA, IgE, and hemoglobin levels significantly increased in both smokers (cigarette and Shisha groups) and passive smokers than in non-smokers group (p0.05). Conclusion: This study concluded that smoking, including cigarette and shisha, even passive smoking harmed health through increasing Malondialdehyde, serum IgE and hs-CRP levels in the body.

Fibromuscular dysplasia (FMD) is predominantly diagnosed in women and is a congenital malformation damaging the arterial cell walls of numerous arteries, most prominently impacting the renal arteries. Although previously believed to be a disease of young women, older patients have been shown to make up a large percentage of this patient population as well. FMD is underdiagnosed, and the misdiagnosis of this disease has life-threatening consequences. Here, we present the case of a 24-year-old woman with hypertension who did not receive adequate workup until her symptoms were unrelenting. Her hypertension was presumed to be a result of her generalised anxiety disorder. However, once she began to experience vision changes and significant headaches, further workup ensued. This case exemplifies the importance of performing a thorough evaluation of all patients that present with hypertension of unknown origin, especially young women. To decrease the risk of permanent consequences such as strokes, renal failure and even death, the correct diagnosis of FMD is vital.

Issues of task scheduling in the centre of cloud computing are becoming more important, and the cost is one of the most important parameters used for scheduling tasks. This study aims to investigate the problem of online task scheduling of the identified job of MapReduce on cloud computing infrastructure. It was proposed that the virtualized cloud computing setup comprised machines that host multiple identical virtual machines (VMs) that need to be activated earlier and run continuously, and booting a VM requires a constant setup time. A VM that remains running even though it is no longer used is considered an idle VM. Furthermore, this study aims to distribute the idle cost of the VMs rather than the cost of setting up them among tasks in a fair manner. This study also is an extension of previous studies which solved the problems that occurred when distributing the idle cost and setting up the cost of VMs among tasks. It classifies the tasks into three groups (long, mid, and short) and distributes the idle cost among the groups then among the tasks of the groups. The main contribution of this paper is the developing of a clairvoyant algorithm that addressed important factors such as the delay and the cost that occurred by waiting to setup VM (active VM). Also, when the VMs are run continually and some VMs become in idle state, the idle cost will be distributed among the current tasks in a fair manner. The results of this study, in comparison with previous studies, showed that the idle cost and the setup cost that was distributed among tasks were better than the idle cost and the setup cost distributed in those studies.

This cross-sectional mixed-method study aimed to investigate the effects of grammatical collocations (GCs) frequency, their L1-L2 congruency and transparency, as well as L2 proficiency on Iraqi EFL university students' (IUSs') productive and receptive knowledge of GCs. The study also involved a comparison between IUSs' productive and receptive collocational knowledge as well as an attempt to explore how consciously aware IUSs and their teachers are of GCs and their different types. In addition, the study attempts to explore the way GCs tend to be learned and taught in the study setting. The study involved 112 participants with different L2 proficiency levels. The data collection instruments included a productive knowledge test, a receptive knowledge test (both innovatively designed by the researcher using the BNC and demonstrated good reliability and validity), the grammar part of the Oxford Placement Test (OPT), and semi-structured interviews. The findings of the study revealed that GC frequency, L1-L2 congruency, transparency and L2 proficiency have not only significant main effects on IUSs' collocational knowledge but also significant interaction effects and that L2 proficiency was the best predictor of IUSs' performance. It was also found that IUSs' receptive knowledge of GCs was significantly better than their productive one. Apart from the most common types of time, place and manner GCs, the participants showed that they did not have sufficient L2 explicit knowledge of GCs and their different types or the ability to use accurate terms to refer to them. Most participants' responses indicated that the type of teaching employed to teach GCs tends to be explicit and intentional, especially at the earlier stages. In addition, the vocabulary items comprising GCs often tend to be taught as individual words (i.e. not as part of the GCs). Moreover, explicit teaching tends to be associated with only the most common types of GCs.

Objectives To examine the utilization of current common treatments by providers from different specialties and the effect on delaying spinal surgery in patients with disk degenerative disease (DDD) related low back pain. Design Retrospective observational study using data from the MarketScan Commercial Claims and Encounters database (2005-2013). Setting Not applicable. Participants Patients (N=6229) newly diagnosed with DDD-related low back pain who received interventional treatments from only 1 provider specialty and continuously enrolled in the database for 3 years after diagnosis. Main Outcome Measures Measures of treatment utilization and cost were constructed for patients who received spinal surgery within 3 years after diagnosis. Cox proportional hazards models were used to examine time to surgery among provider specialties and generalized linear models were used to examine cost differences among provider specialties. Results Of the 6229 patients, 427 (6.86%) underwent spinal surgery with unadjusted mean interventional treatment costs ranging from $555 to $851. Although the differences in mean costs across provider specialties were large, they were not statistically significant. Cox proportional hazards models showed that there was no significant difference between provider specialties in the time from DDD diagnosis to spinal surgery. However, patients diagnosed with DDD at a younger age and receiving physical therapy had significantly delayed time to surgery (hazard ratio, 0.66; 95% confidence interval [CI], 0.54-0.81 and hazard ratio, 0.77; 95% CI, 0.62-0.96, respectively). Conclusions Although there were no statistically significant differences among provider specialties for time to surgery and cost, patients receiving physical therapy had significantly delayed time to surgery.

Introduction To determine the association between magnetic resonance imaging (MRI)-detected vulnerable Carotid Plaques and clinical presentation related to ipsilateral carotid artery territory. Evidence acquisition We searched three databases including Ovid MEDLINE, Ovid EMBASE, and Scopus from 2000 to 2018 for studies that evaluated vulnerable carotid plaques by MRI defined as intraplaque hemorrhage (IPH), lipid-rich necrotic core (LRNC), or thinning/rupture of the fibrous cap (TRFC). Data on study characteristics, clinical presentation, and MRI findings were extracted. Publication bias, methodologic quality, and study heterogeneity were assessed. Random-effects meta-analysis model was used to estimate incidence rate ratio (IRR) and 95% confidence intervals (CI) of MRI-detected vulnerable carotid plaque between symptomatic and asymptomatic arteries. Evidence synthesis Of 2855 studies, 33 studies containing 6210 participants with 8401 assessed arteries were included. Overall, the risk of bias was moderate in 13, and low in 20 studies. The prevalence of MRI-positive IPH, TRFC, and LRNC were higher in symptomatic groups compared with the asymptomatic groups. In 11 studies that compared vulnerable carotid plaques between symptomatic and asymptomatic groups, symptomatic presentation was correlated with increased risk of IPH (IRR=1.57; 95% CI: 1.24-1.99), TRFC (IRR=2.26; 95% CI: 1.83 to 3.76), and LRNC (IRR=1.95; 95% CI: 1.28 to 2.97), respectively. Conclusions The presence of MRI-positive vulnerable carotid plaques including IPH, LRNC, and TRFC is positively associated with symptomatic clinical presentation. Therefore, carotid plaque MRI might be a useful risk stratification tool in determining the risk of ischemic stroke.

The production of number forms in English tends to be problematic for Iraqi learners of English as a foreign language (EFL), even at the undergraduate level. To help better understand and consequently address this problem, it is important to identify its sources. This study aims at: (1) statistically analysing Iraqi EFL undergraduates' performance in the production of number forms in English; (2) classifying learners' errors in terms of their possible major causes; and (3) outlining some pedagogical recommendations relevant to the teaching of number forms in English. It is hypothesized in this study that (1) Iraqi EFL undergraduates still face problems in the production of number forms in English and (2) errors pertaining to the context of learning are more numerous than those attributable to the other possible causes. After reviewing the literature available on the topic, a written test comprising 50 items has been constructed and administered to a randomly chosen sample of 50 second-year college students from the Department of English, College of Education, Wasit University. The findings of the study showed that Iraqi EFL undergraduates still face problems in the production of number forms in English and that the possible major sources of learners’ errors can be arranged hierarchically in terms of the percentages of errors to which they can be ascribed as follows: (1) context of learning (50%), (2) intralingual transfer (37%), and (3) interlingual transfer (13%). It is hoped that the implications of the study findings will be beneficial to researchers, syllabus designers, as well as teachers of English as a foreign/second language.

Grammatical collocations (GCs) are word combinations containing a preposition or a grammatical structure, such as an infinitive (e.g. smile at, interested in, easy to learn, etc.). Such collocations tend to be difficult for Iraqi EFL university students (IUS) to master. To help address this problem, it is important to identify the factors causing it. This study aims at investigating the effects of L2 proficiency, frequency of GCs and their transparency on IUSs’ productive knowledge of GCs. The study involves 112 undergraduate participants with different proficiency levels, learning English in formal contexts in Iraq. The data collection instruments include (but not limited to) a productive knowledge test (designed by the researcher using the British National Corpus (BNC)), as well as the grammar part of the Oxford Placement Test (OPT). The study findings have shown that all the above-mentioned factors have significant effects on IUSs’ productive knowledge of GCs. In addition to establishing evidence of which factors of L2 learning might be relevant to learning GCs, it is hoped that the findings of the present study will contribute to more effective methods of teaching that can better address and help overcome the problems IUSs encounter in learning GCs. The study is thus hoped to have significant theoretical and pedagogical implications for researchers, syllabus designers as well as teachers of English as a foreign/second language.

Background Peripheral arterial disease (PAD) is common and associated with significant morbidity and mortality. PAD can be detected through a noninvasive measurement of the ankle-brachial index (ABI). Methods We conducted a systematic review of several electronic bibliographic databases for studies that evaluated ABI as a screening test for PAD in asymptomatic individuals. We conducted random-effects meta-analysis, reporting pooled hazard ratios (HRs) when appropriate. Results We included 40 individual studies, 2 systematic reviews, and 1 individual-patient data meta-analysis. We found no studies comparing ABI screening with no screening in terms of patient-important outcomes (mortality, amputations). The yield of PAD screening averaged 17% (range, 1%-42%) and was 1% to 4% in lower risk populations. Patients with PAD had higher adjusted risk of all-cause mortality (HR, 2.99; 95% confidence interval, 2.16-4.12) and of cardiovascular mortality (HR, 2.35; 95% confidence interval, 1.91-2.89). Data on benefits, harms, and cost-effectiveness of screening were limited; however, ABI screening was associated with additional prognostic information and risk stratification for heart disease. The overall quality of evidence supporting screening was low. Conclusions The current available evidence demonstrates that PAD is common in patients with multiple cardiovascular risk factors and is associated with significant morbidity and mortality, but it does not support the benefit of routine ABI screening.

Background Peripheral arterial disease is common and is associated with significant morbidity and mortality. Methods We conducted a systematic review to identify randomized trials and systematic reviews of patients with intermittent claudication to evaluate surgery, endovascular therapy, and exercise therapy. Outcomes of interest were death, amputation, walking distance, quality of life, measures of blood flow, and cost. Results We included eight systematic reviews and 12 trials enrolling 1548 patients. Data on mortality and amputation and on cost-effectiveness were sparse. Compared with medical management, each of the three treatments (surgery, endovascular therapy, and exercise therapy) was associated with improved walking distance, claudication symptoms, and quality of life (high-quality evidence). Evidence supporting superiority of one of the three approaches was limited. However, blood flow parameters improved faster and better with both forms of revascularization compared with exercise or medical management (low- to moderate-quality evidence). Compared with endovascular therapy, open surgery may be associated with longer length of hospital stay and higher complication rate but resulted in more durable patency (moderate-quality evidence). Conclusions In patients with claudication, open surgery, endovascular therapy, and exercise therapy were superior to medical management in terms of walking distance and claudication. Choice of therapy should rely on patients' values and preferences, clinical context, and availability of operative expertise.

Les energies renouvelables connaissent une expansion rapide, due non seulement a leur impact limite sur l’environnement mais aussi a leur cout de plus en plus faible. Pour lutter contre le changement climatique, de nouveaux investissements dans les technologies bas-carbone sont necessaires. Outre ses aspects positifs, la transition energetique engendre des risques, notamment geopolitiques. Le concept de securite energetique va etre profondement modifie. Ces risques peuvent etre anticipes et geres.

As Director-General of the International Renewable Energy Agency (IRENA), I accepted with pleasure the opportunity to write about the remarkable transformation of the energy sector by renewable energy technologies. The topic was suggested to me in the gracious invitation by the UN Chronicle, and we will come to it in a moment, for it says a lot about where renewable energy is today and how it is perceived.

Introduction Le nombre de de patients subissant des procedures vasculaires a qui sont prescrits du clopidogrel ou de la warfarine comme options therapeutique continue d’augmenter. Notre but etait d’analyser les resultats de l’utilisation d’un antiplaquettaire ou d’une anti-coagulation chez les patients subissant une endarteriectomie carotidienne (CEA). Methodes Une etude retrospective de 260 patients consecutifs subissant une CEA. Les donnees demographiques, les details operatoires, l’utilisation perioperatoire d’aspirine (ASA), de clopidogrel, ou de warfarine, et les resultats precoces et tardifs ont ete collectes. Les criteres d’evaluation incluaient le taux de morbidite et/ou mortalite postoperatoires et les complications hemorragiques. Resultats L’etude incluait 152 hommes et 108 femmes (âge moyen = 69,3 ans), avec un suivi moyen de 406 jours. En tout, 46% des endarteriectomies etaient realisees pour une lesion symptomatique. La technique d’endarteriectomie de l’eversion a ete appliquee chez 126 patients (48,5%), la pose d’un patch de Dacron dans 112 cas (43,1%), et d’un patch pericardique bovin dans 14 cas (5,4%). Parmi les patients, 171 prenaient de l’ASA, 50 prenaient du clopidogrel ± de l’ASA, et 10 prenaient de la warfarine (INR moyen = 1,62 ; extremes, 1,2-2,1) ; les 29 autres n’etaient sous aucune therapie antiplaquettaire. Tous les patients qui etaient sous warfarine ont subi une endarteriectomie par eversion. De facon generale, il y a eu 19 (7,3%) complications (12 majeures et 7 mineures). Le taux d’accident vasculaire cerebral (AVC) a 30 jours et le taux de mortalite et AVC etaient de 0,7% et 1,1%, respectivement. Les patients prenant du clopidogrel ont developpe davantage d’hematomes cervicaux (16% contre 1,7%, p = 0,0004) compares aux patients qui etaient sous ASA seule. Chez les patients prenant du clopidogrel, la reparation par patch de Dacron a eu comme consequence davantage d’hematomes que l’eversion (35% contre 4,2%, p = 0,012). Il n’y avait aucune difference des techniques d’endarteriectomie sur l’incidence d’hematome cervical chez les patients qui etaient sous ASA seule. Les patients prenant de la warfarine n’ont eu aucune complication perioperatoire et n’ont developpe aucun hematome cervical. Conclusions Dans cette etude, l’utilisation du clopidogrel au cours de la CEA avait comme consequence un risque significatif de developper un hematome cervical, en particulier en cas de patch en Dacron. Le risque d’hematome cervical chez les patients sous clopidogrel etait bien moindre lorsqu’une endarteriectomie par eversion etait realisee.

Objectives Thoracic endografts (stent grafts) have emerged as a less invasive modality to treat various thoracic aortic lesions. The intentional coverage of the left subclavian artery (LSA) during the placement of these endografts is associated with several complications including stroke, spinal cord ischemia, and arm ischemia. In this review, we synthesize the available evidence regarding the complications associated with LSA coverage. Methods We searched electronic databases (MEDLINE and EMBASE) from January 1990 through February 2008 for studies that included patients who received thoracic endografts and had intentional LSA coverage. Eligible studies had a control group that either received the endograft without LSA coverage or had primary revascularization prior to coverage. Two independent reviewers determined trial eligibility and extracted descriptive, methodological and outcome data from each eligible study. Meta-analyses estimated Peto odds ratio (OR) and 95% confidence intervals (CI) to describe the strength of association between coverage and complications; the I 2 statistic described the proportion of inconsistency of treatment effect among studies not due to chance. Results We found 51 eligible observational studies. LSA coverage was associated with significant increase in the risk of arm ischemia (OR 47.7; CI, 9.9-229.3; I 2 = 72%, 19 studies) and vertebrobasilar ischemia (OR 10.8; CI, 3.17-36.7; I 2 = 0%; eight studies); and nonsignificant increase in the risk of spinal cord ischemia (OR 2.69; CI, 0.75-9.68; I 2 = 40%; eight studies) and anterior circulation stroke (OR 2.58; CI, 0.82-8.09; I 2 = 64%, 13 studies). There were no significant associations between LSA coverage and death, myocardial infarction, or transient ischemic attacks. The incidence of phrenic nerve injury as a complication of primary revascularization was 4.40% (CI, 1.60%-12.20%). Data on perioperative infection were sparse and rarely reported. Conclusions Very low quality evidence suggests that LSA coverage increases the risk of arm ischemia, vertebrobasilar ischemia, and possibly spinal cord ischemia and anterior circulation stroke.

Background Endovascular repair (EVR) is emerging as first-line treatment for patients with superior vena cava (SVC) syndrome of benign etiology, but data on its durability remain scarce. The aims of this study were to assess the efficacy and durability of EVR and compare results of EVR with open surgical reconstruction (OSR). Methods Data from 70 consecutive patients undergoing treatment for benign SVC syndrome between November 1983 and November 2006 were retrospectively reviewed. Results There were 30 males and 40 females (mean age, 41 years; range, 5-75 years). Etiology included indwelling catheters or pacemaker wires in 35 patients, mediastinal fibrosis in 31, idiopathic thrombosis in 2, hypercoagulable disorder in 1, and postsurgical thrombosis in 1. In 42 patients, OSR was done through a median sternotomy: repair was with spiral saphenous vein in 22, expanded polytetrafluoroethylene (ePTFE) in 13, femoral vein grafts in 6, and human allograft in 1. Fifteen OSRs followed failed EVR interventions. EVR was attempted in 32 patients and was successful in 28 (88%): 19 had stenting, 14 had percutaneous transluminal balloon angioplasty (PTA), 2 had thrombolytic therapy with PTA, and 3 had stenting. All four technical failures subsequently underwent OSR. There were no early deaths in either group. Periprocedural morbidity was 19% after OSR and 4% in the EVR group. Six early surgical graft failures were successfully treated with surgical revision; one restenosis after EVR was restented. During a mean follow-up of 4.1 years (range, 0.1-17.5 years) after OSR, 11 patients underwent 18 secondary interventions. Mean follow-up after EVR was 2.2 years (range, 0.2-6.4 years), and nine patients underwent 21 secondary EVR interventions. Primary, assisted primary, and secondary patency rates of surgical bypass grafts were, respectively, 45%, 68%, and 75% at 3 and 5 years. Primary, assisted primary and secondary patency rates after EVR were 44%, 96%, and 96% at 3 years. Assisted primary patency was significantly higher in vein grafts than in ePTFE grafts (P = .05). Assisted primary and secondary patency was significantly higher in patients undergoing stenting compared with PTA (P = .02). At last follow-up, 93% of patients in both OSR and EVR groups had significant relief from symptoms. Conclusions OSR of benign SVC syndrome is effective, with durable long-term relief from symptoms. EVR is less invasive but equally effective in the mid-term, albeit at the cost of multiple secondary interventions, and is an appropriate primary treatment for benign SVC syndrome. OSR remains an excellent choice for patients who are not suitable for EVR or in whom the EVR fails.

Objective: Upper extremity ischemia (UEI) is an uncommon condition that can lead to permanent disability. There is a limited understanding of the etiology, management, and outcomes of the disease. Methods: We retrospectively reviewed the charts of all patients who were diagnosed with “embolism and/or thrombosis of arteries of upper extremity” at our institution from January 2005 to December 2013. Results: Patients diagnosed with embolisms were older ( P < .001), more likely to undergo thromboembolectomy ( P < .001), had higher rates of hypertension ( P = .001), and had longer lengths of hospital stay ( P = .002). There were no significant differences in complications or mortality at 30 days and up to 1 year. Conclusion: At our center, embolism was found to be the most common etiology for UEI followed by thrombosis and stenosis. Patients presented with embolism were older, were more likely to undergo thromboembolectomy, and had higher rates of hypertension and longer hospital stays.

Exsanguination after trauma remains a leading cause of early death in severely injured patients [1]. Sepsis and multiple organ failure are significant causes of mortality in severely injured trauma patients who survive their injury and require a prolonged ICU hospitalization [2]. Despite advances in operative technique and critical care medicine, the treatment options for patients with coagulopathic hemorrhage or severe sepsis have remained relatively unchanged. We report a unique case in which pharmacological modulators of coagulation, recombinant Factor VIIa, and activated protein C were successfully used to treat massive hemorr-hage and then severe sepsis in a severely injured trauma patient.

Transplanted adult bone marrow-derived cells (BMDCs) have been shown to adopt the phenotype and function of several nonhematopoietic cell lineages and promote tumorigenesis. Beyond its cancer enhancing potential, cell fusion has recently emerged as an explanation of how BMDCs regenerate diseased heptocytes, contribute to Purkinje neurons and skeletal and cardiac muscle cells, and participate in skin and heart regeneration. Although bone marrow-derived epithelial cells also have been observed in the intestine, fusion as a mechanism has not been investigated. Here, we show that transplanted BMDCs fuse with both normal and neoplastic intestinal epithelium. Long-term repopulation by donor-derived cells was detected in all principal intestinal epithelial lineages including enterocytes, goblet cells, Paneth cells, and enteroendocrine cells, suggesting that the fusion partners of the BMDCs are long-lived intestinal progenitors or stem cells. Fusion of BMDCs with neoplastic epithelium did not result in tumor initiation. Our findings suggest an unexpected role for BMDCs in both regeneration and tumorigenesis of the intestine.

Impalement injuries result when a rigid object penetrates and remains lodged within the body. While these injuries are rare, and many patients die at the scene, they often produce complex surgical problems. Few case reports describe complete spinal cord transection due to impalement. No case reports have described intrathoracic division of a reinforcing steel bar to assist the removal. The authors report a case of impalement by a steel bar resulting in immediate spinal cord transection requiring intraoperative division of the bar with a pneumatic drill for removal. They also present a literature review on thoracic impalement and discuss the general management of these injuries.

Background Hyperbaric oxygen (HBO) is used as an adjunctive therapy for a variety of indications. However, there is a lack of high-quality research evaluating HBO treatment outcomes for different indications available in the current literature. Methods We retrospectively reviewed all patients who underwent HBO therapy at a single hyperbaric center from January 2010 to December 2013 using predetermined criteria to analyze successful, improved, or failed treatment outcomes for the following indications: chronic refractory osteomyelitis, diabetic foot ulcer, failed flap or skin graft, osteoradionecrosis, soft tissue radiation necrosis, and multiple coexisting indications. Results Among the included 181 patients treated with adjunctive HBO at our center, 81.8% had either successful or improved treatment outcomes. A successful or improved outcome was observed in 82.6% of patients treated for chronic refractory osteomyelitis (n = 23), 74.1% for diabetic foot ulcer (n = 27), 75.7% for failed flap or skin graft (n = 33), 95.7% for osteoradionecrosis (n = 23), 88.1% for soft tissue radiation necrosis (n = 42), and 72.4% for multiple coexisting indications (n = 29). Among 4 patients treated for other indications, 100% of the cases were either successful or improved. Conclusions This study has provided a comprehensive outcome survey of using HBO for the previously mentioned indications at our center. It supplements the literature with more evidence to support the consideration of HBO in different indications.

Objective This review was conducted to determine the optimal timing for referring patients with end-stage renal disease to vascular surgery for access placement. Methods A systematic review of the electronic databases (MEDLINE, EMBASE, Current Contents, Cochrane CENTRAL and Web of Science) was conducted through March 2007. Randomized and observational studies were eligible if they compared an early referral cohort with a late referral cohort in terms of patient-important outcomes such as death, access-related sepsis, and hospitalization related to access complications. Results We found no studies that fulfilled eligibility criteria. Conclusion At the present time, the optimal timing for referral to vascular surgery for vascular access placement is based on expert opinion and choices made by patients and physicians.

Current requirements for thoracic aortic endografting, based on device Instructions for Use (IFU), include a proximal aortic “neck” measuring at least 2 cm in length. Not infrequently, this neck length is not available in patients with more proximal aneurysmal disease of the descending thoracic aorta, necessitating coverage of the brachiocephalic trunks (most commonly the left subclavian artery) or preemptive revascularization (either bypass with proximal ligation or transposition). The current literature suggests that the intentional coverage of the left subclavian artery during placement of a thoracic endograft may increase the risk of arm ischemia, vertebrobasilar ischemia, and possibly spinal cord ischemia and anterior circulation stroke. When feasible, revascularization should be performed to reduce this risk. In addition, challenging anatomy may increase the risk of inadvertent endograft coverage of the brachiocephalic trunks.

Objectives: Retrospective case–control study to determine the failure and endovenous heat-induced thrombosis (EHIT) rates of endovenous ablation (EVA) in patients with a history of superficial venous thrombosis (SVT). Methods: Study and control groups each consisted of 73 patients with or without the history of SVT, who underwent EVA between June 2010 and July 2012. All patients were followed with venous duplex ultrasound. Procedural failure and EHIT rates were considered primary outcomes. Results: There was no difference in EHIT or failure rates between study and control groups ( P = 1.00). There was no difference in EHIT or failure rates between patients with and without the history of venous thromboembolism (VTE), with and without the history of VTE and/or SVT, with and without the history of thrombophilia, and on and off anticoagulation for either group or the combined study population. For the combined study population, failure rate was higher in patients with a history of VTE. Conclusions: Although EVA seems to be safe and effective in patients with a history of SVT, vein access in this patient group might require multiple attempts.

Chronic venous ulcer (CVU) is common and is responsible for significant health care expenditures worldwide. Compression is the mainstay of treatment, but long-term compliance with this therapy is often inconsistent, particularly in the elderly and infirm. Surgical ablation of axial and perforator reflux has been used as an adjunct to compression to reduce recurrence rates and assist healing. These surgical techniques are being replaced by minimally invasive procedures, such as thermal ablation and foam sclerotherapy, in the treatment of uncomplicated venous disease. The role for these techniques in the treatment of CVU is just beginning to be defined.Eighty-six patients with CVU with 95 active ulcers (Clinical, Etiology, Anatomy, Physiology-CEAP clinical class 6) presenting to a multispecialty wound clinic were retrospectively reviewed and analyzed by leg. All patients underwent duplex scanning for venous insufficiency. Ulcer dimensions at each visit were recorded and used to calculate healing rates. Presence or absence of ulcer recurrence at 1-year follow-up was recorded. Ulcers treated with compression alone ("compression group") were compared with those treated with compression and minimally invasive interventions, such as thermal ablation of superficial axial reflux and ultrasound-guided foam sclerotherapy (UGFS) of incompetent perforating veins and varicosities ("intervention group").The average age in the intervention and compression groups was 67 and 71 years, respectively (P = not significant [NS]). Body mass index was 32.4 ± 9.5 and 33.6 ± 11.8 kg/m(2), in the compression and intervention groups, respectively (P = not significant [NS]). Ulcers were recurrent in 42% of the intervention group and 26% of the compression group (P = NS). In the intervention group, 33% had radiofrequency ablation of axial reflux, 31% had UGFS of perforators, and 29% had both treatments. The only complication of intervention was a single case of cellulitis requiring hospitalization. Compared with the compression group, the ulcers in the intervention group healed faster (9.7% vs. 4.2% per week; P = 0.001) and showed fewer recurrences at 1-year follow-up (27.1% vs. 48.9 %; P0.015). Multivariate analysis showed use of intervention was the strongest determinant of healing with a coefficient of variation of 7.432, SE 2.406, P = 0.003. Analysis of just the intervention group before and after intervention using matched pairs showed acceleration of healing after intervention from ranging from a median of 1.2% (interquartile range [IQR], 14.3) to 9.7% (IQR, 11.3) per week (P ≤ 0.001).Minimally invasive ablation of superficial axial and perforator vein reflux in patients with active CVU is safe and leads to faster healing and decreased ulcer recurrence when combined with compression alone in the treatment of CVU.

To synthesize the available evidence regarding the outcomes associated with nonoperative management, open repair, and endovascular repair of thoracic aortic transection.We searched electronic databases (MEDLINE, EMBASE Cochrane, Web of Science, and Scopus) for studies that enrolled patients with aortic transection and measured the outcomes of interest. Two reviewers determined study eligibility and extracted data. We estimated the event rate associated with the different approaches from case series and the relative risk from comparative studies. Estimates from each study were pooled using the random effects model.We found 139 studies that fulfilled the inclusion criteria, the majority of which were noncomparative surgical case series, retrospective, and none were randomized. Studies included 7768 patients, the majority of which were males. The mortality rate was significantly lower in patients who underwent endovascular repair, followed by open repair and nonoperative management (9%, 19%, and 46%, respectively, P.01). No significant difference in event rate across the three groups was noted for the outcomes of anterior stroke, posterior stroke, or any stroke. The risk of spinal cord ischemia and end-stage renal disease were higher in open repair compared with the other 2 groups (9% vs 3% and 3%, P = .01 for spinal cord ischemia and 8% vs 5% and 3%, P = .01 for end-stage renal disease). Compared with endovascular repair, open repair was associated with an increased risk of graft infection and systemic infections. Meta-analyses of comparative studies demonstrated that compared with open repair, endovascular repair is associated with reduced mortality and spinal cord ischemia (relative risk, 0.61; 95% confidence interval, 0.46-0.80; and relative risk, 0.34; 95% confidence interval, 0.16-0.74; respectively). Inferences are limited by methodological quality, survival, and publication biases.Very low-quality evidence suggests that, compared with open repair or nonoperative management, endovascular repair of thoracic aortic transection is associated with better survival and decreased risk of spinal cord ischemia, renal injury, and graft and systemic infections. Nonoperative management is associated with the least favorable outcomes.

The use of thoracic stent grafts to manage patients with various aortic pathologies is a rapidly expanding area in the field of vascular surgery. It has supplanted traditional open surgery in the treatment of many specific aortic diseases, including descending thoracic aneurysms, acute complicated dissection, traumatic transection, and penetrating ulcers. Because of the need for an adequate proximal seal zone and limitations of current technology of stent grafts, the left subclavian artery (LSA) may need to be covered in 26% to 40% of patients undergoing thoracic endovascular aortic repair (TEVAR). 1,2 In the first United States regulatory trial, 3 all patients were required to undergo prophylactic LSA revascularization before TEVAR if the LSA was covered, but this practice has not become predominant in clinical practice. There is great variability amongst surgeons and interventionalists about which patient undergoes LSA revascularization before TEVAR. Some surgeons perform routine LSA revascularization, whereas others are selective, such as in cases of a left vertebral artery ending at the posterior inferior cerebellar artery, a prior left internal mammary-to-coronary artery bypass, or an absent distal right vertebral artery. Lastly, some surgeons only perform LSA revascularization if symptoms of left arm ischemia or subclavian steal syndrome occur after TEVAR. 1,4,5 Unfortunately, most of the data about LSA coverage during TEVAR and the morbidity and mortality associated with this come from single institutional series or registries, thus the current management of the LSA when coverage is necessary is not uniform. The Society for Vascular Surgery ® (SVS) recently formed a Committee on Aortic Disease to formulate clinical practice guidelines to aid physicians and patients regarding LSA revascularization during TEVAR. A third-party, the Knowledge and Encounter Research Unit, Mayo Clinic, Rochester, performed a comprehensive literature review and formulated a systematic review and meta-analysis relating the effect of LSA coverage on the morbidity and mortality of patients undergoing TEVAR. 6 The SVS used this review and the consensus of the committee to develop three recommendations regarding LSA revascularization in relationship to TEVAR. 7 This article reviews the potential complications associated with LSA coverage and summarizes the SVS Practice Guidelines in the management of the LSA during TEVAR.

Background The number of cases involving patients undergoing vascular procedures who are prescribed clopidogrel or warfarin as treatment options continues to rise. Our aim was to examine outcomes related to antiplatelet or anticoagulation therapy in patients undergoing carotid endarterectomy (CEA). Methods A retrospective review of 260 consecutive patients undergoing CEA. Data including patient demographics, operative details, perioperative use of aspirin (ASA), clopidogrel, or warfarin, and early and/or late outcome(s) were collected. Endpoints included postoperative morbidity and/or mortality rate(s) and bleeding complications. Results The study included 152 men and 108 women (mean age = 69.3 years), with a mean follow-up of 406 days. In all, 46% of endarterectomies were for a symptomatic disease. The technique of eversion endarterectomy was applied in 126 (48.5%), Dacron-patch in 112 (43.1%), and bovine pericardial-patch in 14 (5.4%) of the cases. Among the patients, 171 were taking ASA, 50 were taking clopidogrel ± ASA, and 10 were taking warfarin (mean INR = 1.62; range, 1.2-2.1); the remaining 29 were not on any antiplatelet therapy. All patients who were on warfarin therapy underwent an eversion endarterectomy. Overall, there were 19 (7.3%) complications (12 major and seven minor). The 30-day stroke rate and stroke death rate was 0.7% and 1.1%, respectively. Patients taking clopidogrel developed more number of neck hematomas (16% vs. 1.7%, p = 0.0004) compared with patients who were on ASA alone. For patients taking clopidogrel, Dacron-patch repair resulted in more hematomas than eversion endarterectomy (35% vs. 4.2%, p = 0.012). There was no difference in the incidence of neck hematoma on the basis of endarterectomy technique in patients who were on ASA alone. The patients taking warfarin neither had a perioperative complication nor developed a neck hematoma. Conclusions In this study, clopidogrel use during CEA resulted in a significant risk for developing a neck hematoma, particularly when using a Dacron-patch. The risk of a neck hematoma in patients who were on clopidogrel was much less when an eversion endarterectomy was performed.

Objectives The autogenous arteriovenous access for chronic hemodialysis is recommended over the prosthetic access because of its longer lifespan. However, more than half of the United States dialysis patients receive a prosthetic access. We conducted a systematic review to summarize the best available evidence comparing the two accesses types in terms of patient-important outcomes. Methods We searched electronic databases (MEDLINE, EMBASE, Cochrane CENTRAL, Web of Science and SCOPUS) and included randomized controlled trials and controlled cohort studies. We pooled data for each outcome using a random effects model to estimate the relative risk (RR) and its associated 95% confidence interval (CI). We estimated inconsistency caused by true differences between studies using the I 2 statistic. Results Eighty-three studies, of which 80 were nonrandomized, met eligibility criteria. Compared with the prosthetic access, the autogenous access was associated with a significant reduction in the risk of death (RR, 0.76; 95% CI, 0.67-0.86; I 2 = 48%, 27 studies) and access infection (RR, 0.18; 95% CI, 0.11-0.31; I 2 = 93%, 43 studies), and a nonsignificant reduction in the risk of postoperative complications (hematoma, bleeding, pseudoaneurysm and steal syndrome, RR 0.73; 95% CI, 0.48-1.16; I 2 = 65%, 31 studies) and length of hospitalization (pooled weighted mean difference –3.8 days; 95% CI, –7.8 to 0.2; P = .06). The autogenous access also had better primary and secondary patency at 12 and 36 months. Conclusion Low-quality evidence from inconsistent studies with limited protection against bias shows that autogenous access for chronic hemodialysis is superior to prosthetic access.

Background Renal artery aneurysms (RAAs) are rare, with little known about their natural history and growth rate or their optimal management. The specific objectives of this study were to (1) define the clinical features of RAAs, including the precise growth rate and risk of rupture, (2) examine the current management and outcomes of RAA treatment using existing guidelines, and (3) examine the appropriateness of current criteria for repair of asymptomatic RAAs. Methods A standardized, multi-institutional approach was used to evaluate patients with RAAs at institutions from all regions of the United States. Patient demographics, aneurysm characteristics, aneurysm imaging, conservative and operative management, postoperative complications, and follow-up data were collected. Results A total of 865 RAAs in 760 patients were identified at 16 institutions. Of these, 75% were asymptomatic; symptomatic patients had difficult-to-control hypertension (10%), flank pain (6%), hematuria (4%), and abdominal pain (2%). The RAAs had a mean maximum diameter of 1.5 ± 0.1 cm. Most were unilateral (96%), on the right side (61%), saccular (87%), and calcified (56%). Elective repair was performed in 213 patients with 241 RAAs, usually for symptoms or size >2 cm; the remaining 547 patients with 624 RAAs were observed. Major operative complications occurred in 10%, including multisystem organ failure, myocardial infarction, and renal failure requiring dialysis. RAA repair for difficult-to-control hypertension cured 32% of patients and improved it in 26%. Three patients had ruptured RAA; all were transferred from other hospitals and underwent emergency repair, with no deaths. Conservatively treated patients were monitored for a mean of 49 months, with no acute complications. Aneurysm growth rate was 0.086 cm/y, with no difference between calcified and noncalcified aneurysms. Conclusions This large, contemporary, multi-institutional study demonstrated that asymptomatic RAAs rarely rupture (even when >2 cm), growth rate is 0.086 ± 0.08 cm/y, and calcification does not protect against enlargement. RAA open repair is associated with significant minor morbidity, but rarely a major morbidity or mortality. Aneurysm repair cured or improved hypertension in >50% of patients whose RAA was identified during the workup for difficult-to-control hypertension.

Ambulatory 24-hour esophageal pH measurement is the standard for detecting abnormal esophageal acid exposure (AEAE), but it has a false negative rate of 15% to 30%. Wireless 48-hour pH monitoring (Bravo; Medtronic, Shoreview, MN) may allow more accurate detection of AEAE versus 24-hour pH monitoring. Forty-eight-hour wireless data were reviewed from 209 patients at three different tertiary care referral centers between 2003 and 2005. Manometric or endoscopic determination of the lower esophageal sphincter helped place the Bravo probe 5 to 6 cm above the lower esophageal sphincter. A total of 190 studies in 186 patients had sufficiently accurate data. There were 114 women and 72 men with an average age of 51 years. AEAE was defined by a Johnson-DeMeester score greater than 14.7 and was obtained in 115 of 190 studies (61%). Only 64 of 115 patients (56%) demonstrated AEAE for both days of the study, whereas 51 of 115 patients (44%) demonstrated AEAE in a single 24-hour period. There was no difference in the prevalence of AEAE on day 1 versus day 2 only (26% vs. 18%, P = .26). Compared with 24-hour alone data, 48-hour data showed 22% more patients with AEAE. Frequent day-to-day variability in patients with AEAE may be missed by a single 24-hour pH test. Forty-eight-hour pH testing may increase detection accuracy and sensitivity for AEAE by as much as 22%.

Stem cells hold the promise of novel therapy for treating diseases. Unfortunately, the use and study of embryonic stem cells are currently clouded by ethical controversy. Adult stem cells offer a unique alternative in that they may be isolated, studied, or manipulated without harming the donor. Currently, several obstacles for use of adult stem cells as therapy exist. First, the ability to identify most adult stem cells is impeded by lack of stem cell markers. Second, in vitro systems for manipulating adult stem cell populations are often not well defined. Finally, our understanding of how adult stem cells are regulated within their niche is in its infancy. Next to the hematopoietic stem cell, epithelial stem cells are one of the most widely studied stem cell populations. Even so, the diversity between epithelial functions in different organs makes it difficult to determine whether common themes exist in regulating these related stem cells. Although each epithelial stem cell niche possesses unique features to facilitate its specialized functionality, they likely share many common aspects of regulation. The purpose of this review is to compare how the cell signaling influences the stem cell and its niche in rapidly self-renewing epithelia.

Purpose To develop a safe functional magnetic resonance imaging (fMRI) procedure for auditory assessment of deaf subjects. Materials and Methods A gold-plated tungsten electrode has been developed which has zero magnetic susceptibility. Used with carbon leads and a carbon reference pad, it enables safe, distortion-free fMRI studies of deaf subjects following direct electrical stimulation of the acoustic nerve. Minor pickup of the radio frequency (RF) pulses by the electrode assembly is difficult to eliminate, and a SPARSE acquisition sequence is used to avoid any effects of unintentional auditory nerve stimulation. Results The procedure is demonstrated in a deaf volunteer. Activation is observed in the contralateral but not the ipsilateral primary auditory cortex. This is in sharp contrast to studies of auditory processing in hearing subjects, but consistent with the small number of previous positron emission tomography (PET) and MR studies on adult deaf subjects. Conclusion The fMRI procedure is able to demonstrate whether the auditory pathway is fully intact, and may provide a useful method for preoperative assessment of candidates for cochlear implantation. J. Magn. Reson. Imaging 2002;16:6–12. © 2002 Wiley-Liss, Inc.

16-year-old female patient presented with a 2-month istory of gastrointestinal bleeding and anemia. Upper and ower endoscopy, small bowel enteroclysis, and a Meckel’s echnetium scan were normal. She presented to our instiution with continued gastrointestinal bleeding and a heatocrit of 16%. A repeat Meckel’s technetium scan, olonoscopy, and upper endoscopy with enteroscopy to the id-jejunum were normal. Angiography (A) revealed a vasular lesion in the ileum suggestive of an arteriovenous malormation. Laparotomy (B) confirmed a 2-cm nodular vasular malformation located 4.5 feet proximal to the leocecal valve. A small bowel resection and primary anasamosis were performed. Gross inspection (C) revealed a .5-cm soft, red, raised nodule on the mucosal surface. istology (D) confirmed an arteriovenous malformation. he patient was discharged on postoperative day 4 with a table hematocrit. Arteriovenous malformations (AVM) of the small intesine are rare, and the true incidence is unknown.The terms rteriovenous malformation, angiodysplasia, telangiectasia, nd hemangioma describe distinct entities but have been sed interchangeably to describe the same lesion.The nonniform classification of intestinal vascular lesions in the iterature has led to some of the confusion and inaccurate eporting.

ObjectivesTo synthesize the available evidence regarding the outcomes associated with nonoperative management, open repair, and endovascular repair of thoracic aortic transection.MethodsWe searched electronic databases (MEDLINE, EMBASE Cochrane, Web of Science, and Scopus) for studies that enrolled patients with aortic transection and measured the outcomes of interest. Two reviewers determined study eligibility and extracted data. We estimated the event rate associated with the different approaches from case series and the relative risk from comparative studies. Estimates from each study were pooled using the random effects model.ResultsWe found 139 studies that fulfilled the inclusion criteria, the majority of which were noncomparative surgical case series, retrospective, and none were randomized. Studies included 7768 patients, the majority of which were males. The mortality rate was significantly lower in patients who underwent endovascular repair, followed by open repair and nonoperative management (9%, 19%, and 46%, respectively, P < .01). No significant difference in event rate across the three groups was noted for the outcomes of anterior stroke, posterior stroke, or any stroke. The risk of spinal cord ischemia and end-stage renal disease were higher in open repair compared with the other 2 groups (9% vs 3% and 3%, P = .01 for spinal cord ischemia and 8% vs 5% and 3%, P = .01 for end-stage renal disease). Compared with endovascular repair, open repair was associated with an increased risk of graft infection and systemic infections. Meta-analyses of comparative studies demonstrated that compared with open repair, endovascular repair is associated with reduced mortality and spinal cord ischemia (relative risk, 0.61; 95% confidence interval, 0.46-0.80; and relative risk, 0.34; 95% confidence interval, 0.16-0.74; respectively). Inferences are limited by methodological quality, survival, and publication biases.ConclusionsVery low-quality evidence suggests that, compared with open repair or nonoperative management, endovascular repair of thoracic aortic transection is associated with better survival and decreased risk of spinal cord ischemia, renal injury, and graft and systemic infections. Nonoperative management is associated with the least favorable outcomes.

Objectives Hemodialysis centers regularly survey arteriovenous (AV) accesses for signs of dysfunction. In this review, we synthesize the available evidence to determine to what extent proactive vascular access monitoring affects the incidence of AV access thrombosis and abandonment compared with clinical monitoring. Methods We searched electronic databases (MEDLINE, EMBASE, Cochrane CENTRAL, Web of Science, and SCOPUS) and sought references from experts, bibliographies of included trials, and articles that cited included studies. Two reviewers independently assessed trial quality and extracted data. We used random effects meta-analysis to estimate the pooled relative risk (RR) and 95% confidence interval (CI) across studies and conducted subgroup analyses to explain heterogeneity. The I 2 statistic was used to assess heterogeneity of treatment effect among trials. Results Nine studies (1363 patients) compared a strategy of surveillance vs clinical monitoring. A vascular intervention to maintain or restore patency was provided to both groups if needed. Surveillance followed by intervention led to a nonsignificant reduction of the risk of access thrombosis (RR, 0.82; 95% CI, 0.58-1.16; I 2 = 37%) and access abandonment (RR, 0.80; 95% CI, 0.51-1.25; I 2 = 60%). Three studies (207 patients) compared the effect of vascular interventions vs observation in patients with abnormal surveillance result. Vascular interventions after an abnormal AV access surveillance led to a significant reduction of the risk of access thrombosis (RR, 0.53; 95% CI, 0.36-0.76) and a nonsignificant reduction of the risk of access abandonment (RR, 0.76; 95% CI, 0.43-1.37). Conclusion Very low quality evidence yielding imprecise results suggests a potentially beneficial effect of AV access surveillance followed by interventions to restore patency. This inference, however, is weak and will require randomized trials of AV access surveillance vs clinical monitoring for rejection or confirmation.