bluuebunny/crossref_metadata_2025_split huggingface dataset:
Extended Follow-Up of Unruptured Intracranial Aneurysms Detected by Presymptomatic Screening in Patients with Autosomal Dominant Polycystic Kidney Disease
Authors: Irazabal Maria V. , Huston John , Kubly Vickie , Rossetti Sandro , Sundsbak Jamie L. , Hogan Marie C. , Harris Peter C. , Brown Robert D. , Torres Vicente E. 
Published: May 2011

Summary

Background and objectives
Autosomal dominant polycystic kidney disease (ADPKD) patients have an increased risk for intracranial aneurysms (IAs). The importance of screening for unruptured IAs (UIAs) depends on their risks for growth and rupture.

Design, setting, participants, & measurements
ADPKD patients with UIAs found by presymptomatic screening with magnetic resonance angiography (MRA) during 1989 to 2009 were followed initially at 6 months and annually, and less frequently after demonstration of stability.

Results
Forty-five saccular aneurysms were detected in 38 patients from 36 families. Most were small (median diameter 3.5 mm) and in the anterior circulation (84%). Median age at diagnosis was 49 years. During cumulative imaging follow-up of 243 years, one de novo UIA was detected and increased in size from 2 to 4.4 mm over 144 months and two UIAs grew from 4.5 to 5.9 mm and 4.7 to 6.2 mm after 69 and 184 months, respectively. Seven patients did not have imaging follow-up. No change was detected in the remaining 28 patients. During cumulative clinical follow-up of 316 years, no aneurysm ruptured. Five patients died from unrelated causes and two were lost to follow-up after 8 and 120 months. Three patients underwent surgical clipping.

Conclusions
Most UIAs detected by presymptomatic screening in ADPKD patients are small and in the anterior circulation. Growth and rupture risks are not higher than those of UIAs in the general population. These data support very selective screening for UIAs in ADPKD patients, and widespread screening is not indicated.
Paradoxical Embolism after Declotting of Hemodialysis Fistulae/Grafts in Patients with Patent Foramen Ovale
Authors: Wu Steven , Ahmad Iftikhar , Qayyum Sohail , Wicky Stephan , Kalva Sanjeeva P. 
Published: May 2011

Summary

Background and objectives
The safety of percutaneous endovascular declotting procedures for thrombosed hemodialysis fistulae/grafts is well described in the general population; however, its safety in the presence of a patent foramen ovale (PFO) is not known. The objective of this study is to assess the incidence of symptomatic paradoxical embolic events associated with declotting procedure of thrombosed arteriovenous (AV) graft or fistula in patients with documented PFO.

Design, setting, participants, & measurements
This was a retrospective study in a hospital-based, academic practice. It included 23 patients (10 men; mean age, 65) with PFO and thrombosed hemodialysis graft/fistula who underwent a standardized declotting procedure with 2 mg of Alteplase and balloon thrombectomy. Twenty patients (87%) had AV grafts, and three (13%) had AV fistulae. The PFO shunt was right to left in two (9%), left to right in eight (34%), and bidirectional in ten (44%). The shunt direction was not specified in three patients (13%). The technical success of the declotting procedure and the frequency of clinically manifested paradoxical embolic events in this patient population were calculated.

Results
Fifty declotting procedures were performed on 23 patients with a technical success rate of 96% (48 of 50, 96%). No symptomatic paradoxical embolic events were found in any of the 23 patients with PFO.

Conclusions
Symptomatic paradoxical embolic events after percutaneous endovascular declotting procedures of thrombosed AV grafts and fistulae in patients with documented PFO are rare. This procedure appears to be safe in patients with a PFO.
Patterns and Prognostic Value of Total and Differential Leukocyte Count in Chronic Kidney Disease
Authors: Agarwal Rajiv , Light Robert P. 
Published: May 2011

Summary

Background and objectives
The purpose of this study was to evaluate the levels and patterns of total and differential leukocyte counts and their prognostic importance in a cohort of people with and without chronic kidney disease (CKD).

Design, setting, participants, & measurements
Among 153 veterans without CKD and 267 with, blood leukocyte count was measured at baseline and then repeatedly over a decade. The patterns of change in leukocyte count between the two groups were compared. In the CKD cohort, the spikes in leukocyte counts were compared to the combined endpoint of ESRD and death.

Results
Patients with CKD had more granulocytes and eosinophils and fewer lymphocytes. Over time, granulocytes increased and lymphocytes decreased in those with and without CKD. In addition, in those with CKD, over time eosinophils fell and monocytes increased. Compared with their non-CKD counterparts, patients with CKD had between 1.5- and 3.0-fold more spikes in leukocyte counts. Independent risk factors for the combined endpoint were associated with spikes in the leukocyte counts of absolute and percent eosinophil count, percent granulocyte, and percent monocyte counts. In a multivariate adjusted joint model, both granulocyte and monocyte spikes were independently associated with ESRD and death (hazard ratio 1.67 and 1.52 respectively, P < 0.05).

Conclusions
Compared with those without CKD, patients with CKD have more eosinophils and granulocytes and fewer lymphocytes. Greater variation in leukocytes is seen. Spikes in granulocyte and monocyte percentages among patients with CKD are of independent prognostic importance.
Determinants of enamel decalcification during simulated orthodontic treatment
Authors: Hess Elizabeth , Campbell Phillip M. , Honeyman Allen L. , Buschang Peter H. 
Published: May 2011

Abstract

Objective:
To determine the relative effects that phosphoric acid etching, metal brackets, composite resin adhesives, and filled resin sealants have on enamel decalcification.

Materials and Methods:
One hundred and fifty teeth were randomly divided into six groups to test the effects of acid etching, brackets, and a composite resin adhesive. The right side of each tooth was sealed. The teeth were submitted to a simulated carious challenge by Streptococcus mutans in a nutritive media for 42 days. Scanning electron photomicrographs (SEMs) were used to qualitatively evaluate the tooth surfaces. DIAGNOdent laser fluorescence was used to quantify the decalcification changes that occurred.

Results:
SEMs showed normal enamel on the control teeth, etching patterns on the acid-etched teeth, surface degradation on the teeth that had resin, and sealant tags on the sealed side. The untreated control group showed significantly less decalcification (P ≤ .05) than did all groups except the no etch+bracket group. The no etch+bracket group showed significantly less decalcification than did the etch+bracket, no etch+resin, and the etch+resin groups. Acid-etched teeth demonstrated significantly more decalcification (34%) than did those that were not etched. The teeth with resin showed significantly more decalcification (24%) than did those without resin. There was no significant difference between teeth that did and did not have brackets. The unsealed side of the teeth showed small amounts of—but significantly more—decalcification (5%) compared to the sealed side.

Conclusions:
Acid etching and composite resin adhesives increase enamel decalcification in vitro, while brackets do not. Filled resin sealants protect the teeth from decalcification.
Viscoelastic changes in the blood and vascular wall in a pulsating circular flow
Authors: Beraia Merab , Todua Fridon , Khomeriki Irina 
Published: May 2011

Viscoelastic changes in the blood and vascular wall in a pulsating circular flow
Altered flow conditions, such as separation and recirculationg zones, low and oscillatory shear stress, play an important role in the development of arterial disease. Endothelial denudation by the blood flow is the first step in atherosclerosis. The description of blood flow in vivo is complicated due to the viscoelasticity of vessel walls. However, conventional researches of the effect of the blood vessel viscoelasticity on the blood pressure wave propagation using non-linear one-dimensional models do not take into account the viscoelasticity, despite it being importance in the analysis of pulse wave propagation in arteries.
The purpose of this paper is to study the impact of the arterial pulse wave on the viscoelastic blood flow and initial factors of atherosclerosis.
In 12 healthy men (25-39 years of age) peak velocity, mean velocity, mean flow and net flow in the aorta have been investigated by MR angiography.
Initial velocity was registered after 43msec of the ECG-R wave, and it differed from zero at all sites of the aorta, although net flow was equal to zero. Womersley's number from the ascending to the thoracic aorta decreased from 12.5 ± 1.5 to 7.3 ± 1.2; flow modified from inertio-elastic to viscous. Pulse pressure wave move on artery walls fifteen or more times more rapidly than the blood flow. In the aortic arch in protodiastole blood flow separated into the opposite directed streams resulting in wave superposition with the high net flow. At the isthmus area separated waves interferences and reflects to anterograde direction.
Pulse oscillation increases strain rate to the contiguous vessel wall flow layers. At the sites with the flow wave negative interference vessel pulse oscillation attenuates and at the boundary reflection flow wave can shift the vessel wall.
Study of dosimetric variation due to interfraction organ movement in High Dose Rate Interstital (MUPIT) brachytherapy for gynecologic malignancies
Authors: Velmurugan Thanigaimalai , Sukumar Prabakar , Krishnappan Chokkalingam , Boopathy Raghavendiran 
Published: May 2011

Study of dosimetric variation due to interfraction organ movement in High Dose Rate Interstital (MUPIT) brachytherapy for gynecologic malignancies
Ten patients with cancer of uterine cervix who underwent interstitial brachytherapy using MUPIT templates were CT scanned (CT1) using which bladder, rectum and CTV were delineated. The treatment plan PCT1 was generated and optimized geometrically on the volume. CT scan (CT2) was repeated before the second fraction of the treatment CTV and critical organs were delineated. The plan (PCT2) was created by reproducing the Plan PCT1 in the CT2 images and compared with PCT1. Bladder, Rectum and CTV percentage volume variation ranges from +28.6% to -34.3%, 38.4% to -14.9% and 8.5% to -15.2% respectively. Maximum dose variation in bladder was +17.1%, in rectum was up to +410% and in CTV was -13.0%. The dose to these structures varies independently with no strong correlation with the volume variation. Hence it is suggested that repeat CT and re-planning is mandatory before second fraction execution.
Baseline survey of level of quality control in medical radiology in Cross River State, Nigeria
Authors: Inyang S. , Egbe N. , Inyang I. , Oshi D. 
Published: May 2011

Baseline survey of level of quality control in medical radiology in Cross River State, Nigeria
Quality control (QC) in radiology is meant to ensure that accurate diagnoses are obtained with radiation doses kept as low as reasonably achievable. It is also a fundamental requirement by the Regulatory Authorities in issuing operational license to operators of radiology facilities. In Nigeria, QC issues in Radiation Medicine have recently been introduced and are being enforced by the Nigerian Nuclear Regulatory Authority (NNRA). The level of QC practice in the radiology facilities in Cross River State, Nigeria was evaluated to obtain baseline information that could be relied on in the future to determine the level of improvement. It was observed that radiology practitioners appreciate QC and its importance in their practice, the present low level of its implementation notwithstanding.
Histopathological features with angiographic correlates of internal carotid artery pseudo-occlusion: impact of plaque compositions
Authors: Hirata Yoko , Sakata Noriyuki , Inoue Tooru , Yasumori Kotaro , Yasaka Masahiro , Okada Yasushi 
Published: May 2011

Object
This study describes clinicopathological characteristics of pseudo-occlusion of the internal carotid artery with regard to its possible mechanisms.

Methods
The authors retrospectively reviewed 17 patients with pseudo-occlusion and 23 with high-grade stenosis (North American Symptomatic Carotid Endarterectomy Trial criteria ≥ 90%, but no collapsed distal internal carotid artery) who underwent carotid endarterectomy. Atherosclerotic risk factors, clinical presentation, angiographic findings, and histological features of plaque obtained from the carotid endarterectomy were investigated and comparisons were made between groups.

Results
Plaques obtained in the pseudo-occlusion group were significantly more fibrous and less atheromatous than those in the high-grade stenosis group. Old, organized thrombi were more frequently found in pseudo-occlusion group plaques than in high-grade stenosis group plaques. Plaques acquired in the pseudo-occlusion group had 2 different histological features: the presence or absence of the original lumen. The pseudo-occlusion plaques with total occlusion and recanalization (8 patients) were composed of thrombotic total occlusion with lumen recanalization by large neovascular channels, whereas those with severe stenosis (9 patients) were fibrous or fibroatheromatous and had severe stenosis of the original lumen. In patients with pseudo-occlusion and total occlusion and recanalization, the authors observed a significantly higher incidence of transient ischemic attack and anterior communicating artery–posterior communicating artery collateral flow than those with high-grade stenosis and pseudo-occlusion with severe stenosis.

Conclusions
Plaques of the pseudo-occlusion group were more fibrous than those of the high-grade stenosis group and had 2 different histological features: pseudo-occlusion with total occlusion and recanalization or pseudoocclusion with severe stenosis. This difference in plaque histology may be related to the clinical features of pseudoocclusion, such as symptoms and collateral flow patterns.
A 10-year experience of radiosurgical treatment for cerebral arteriovenous malformations: a perspective from a series with large malformations
Authors: Murray Gisela , Brau Ricardo H. 
Published: May 2011

Object
The purpose of this study was to describe a 10-year experience in the use of radiosurgery (RS) for patients with arteriovenous malformations (AVMs) in Puerto Rico.

Methods
This retrospective analysis was performed for all patients with AVMs treated with RS by the senior author (R.H.B.) in Puerto Rico. Between February 1999 and December 2009, a total of 83 patients underwent the procedure. All charts were reviewed for recollection of demographic data, and AVM and treatment characteristics. Clinical and radiographic follow-up information was collected retrospectively.

Results
Eighty-three patients were treated and 86 RS procedures for AVMs were performed during a 10-year period. Eight patients were lost to follow-up. The remaining 75 patients included 36 males and 39 females, whose median age was 34.5 years. Hemorrhage was the initial presentation in 40% of patients. Fifty-seven AVMs (73%) were treated previously with endovascular neurosurgery, without success. The median volume of the malformation was 17.7 ml. Nearly 65% of the malformations were considered large (≥ 10 ml) in volume. Forty patients had AVMs with largest diameter ≥ 3.5 cm.
The overall obliteration rate was 56.4%, and the median time for obliteration was 29 months. The AVMs ≥ 3.5 cm in diameter had a greater latency period than those < 3.5 cm (31 months vs 46 months, respectively; p = 0.01). In addition, AVM obliteration was inversely associated with its volume, especially in large lesions (p = 0.037). In bivariate analysis, patients achieving obliteration had lower Spetzler-Martin scores compared with patients in whom obliteration was not achieved (p = 0.009). Postradiosurgery hemorrhages were seen in 9 cases. Eleven patients underwent surgery after RS. Major neurological deficits developed in 9 patients, whereas 17 had only minor deficits. The occurrence of neurological deficits was significantly associated with lesions with volume ≥ 10 ml.

Conclusions
Radiosurgery is a reasonable treatment option for AVMs in the majority of cases, in spite of the large, difficult-to-treat malformations.
Comprehensive analysis of risk factors for seizures after deep brain stimulation surgery
Authors: Pouratian Nader , Reames Davis L. , Frysinger Robert , Elias W. Jeff 
Published: May 2011

Object
The aim of this study was to assess risk factors for postoperative seizures after deep brain stimulation (DBS) lead implantation surgery and the impact of such seizures on length of stay and discharge disposition.

Methods
The authors reviewed a consecutive series of 161 cases involving patients who underwent implantation of 288 electrodes for treatment of movement disorders at a single institution to determine the absolute risk of postoperative seizures, to describe the timing and type of seizures, to identify statistically significant risk factors for seizures, and to determine whether there are possible indications for seizure prophylaxis after DBS lead implantation. The electronic medical records were reviewed to identify demographic details, medical history, operative course, and postoperative outcomes and complications. To evaluate significant associations between potential risk factors and postoperative seizures, both univariate and multivariate analyses were performed.

Results
Seven (4.3%) of 161 patients experienced postoperative seizures, all of which were documented to have been generalized tonic-clonic seizures. In 5 (71%) of 7 cases, patients only experienced a single seizure. Similarly, in 5 of 7 cases, patients experienced seizures within 24 hours of surgery. In 6 (86%) of the 7 cases, seizures occurred within 48 hours of surgery. Univariate analysis identified 3 significant associations (or risk factors) for postoperative seizures: abnormal findings on postoperative imaging (hemorrhage, edema, and or ischemia; p < 0.001), age greater than 60 years (p = 0.021), and transventricular electrode trajectories (p = 0.023). The only significant factor identified on multivariate analysis was abnormal findings on postoperative imaging (p < 0.0001, OR 50.4, 95% CI 5.7–444.3). Patients who experienced postoperative seizures had a significantly longer length of stay than those who were seizure free (mean ± SD 5.29 ± 3.77 days vs 2.38 ± 2.38 days; p = 0.002, Student 2-tailed t-test). Likewise, final discharge to home was significantly less likely in patients who experienced seizures after implantation (43%) compared with those patients who did not (92%; p = 0.00194, Fisher exact test).

Conclusions
These results affirm that seizures are an uncommon complication of DBS surgery and generally occur within 48 hours of surgery. The results also indicate that hemorrhage, edema, or ischemia on postoperative images (“abnormal” imaging findings) increases the relative risk of postoperative seizures by 30- to 50-fold, providing statistical credence to the long-held assumption that seizures are associated with intracranial vascular events. Even in the setting of a postimplantation imaging abnormality, long-term anticonvulsant therapy will not likely be required because none of our patients developed chronic epilepsy.
High Prevalence of Liver Fibrosis Associated with HIV Infection: A Study in Rural Rakai, Uganda
Authors: Stabinski Lara , Reynolds Steven J , Ocama Ponsiano , Laeyendecker Oliver , Ndyanabo Anthony , Kiggundu Valerian , Boaz Iga , Gray Ron H , Wawer Maria , Thio Chloe , Thomas David L , Quinn Thomas C , Kirk Gregory D , Program Rakai Health Sciences 
Published: May 2011

Background Liver disease is a leading cause of mortality among HIV-infected persons in the United States and Europe. However, data regarding the effects of HIV and antiretroviral therapy (ART) on liver disease in Africa are sparse. Methods A total of 500 HIV-infected participants in an HIV care programme in rural Rakai, Uganda were frequency-matched by age, gender and site to 500 HIV-uninfected participants in a population cohort. All participants underwent transient elastography (FibroScan®) to quantify liver stiffness measurements (LSM) and identify participants with significant liver fibrosis, defined as LSM≥9.3 kPa (≍ Metavir F≥2). Risk factors for liver fibrosis were identified by estimating adjusted prevalence risk ratios (adjPRR) and 95% CI using modified Poisson multivariate regression. Results The prevalence of hepatitis B coinfection in the study population was 5%. The prevalence of significant fibrosis was 17% among HIV-infected and 11% in HIV-uninfected participants ( P=0.008). HIV infection was associated with a 50% increase in liver fibrosis (adjPRR 1.5, 95% CI 1.1–2.1; P=0.010). Fibrosis was also associated with male gender (adjPRR 1.4, 95% CI 1.0–1.9; P=0.045), herbal medicine use (adjPRR 2.0, 95% CI 1.2– 3.3; P=0.005), heavy alcohol consumption (adjPRR 2.3, 95% CI 1.3–3.9; P=0.005), occupational fishing (adjPRR 2.5, 95% CI 1.2–5.3; P=0.019) and chronic HBV infection (adjPRR 1.7, 95% CI 1.0–3.1; P=0.058). Among HIV-infected participants, ART reduced fibrosis risk (adjPRR 0.6, 95% CI 0.4–1.0; P=0.030). Conclusions The burden of liver fibrosis among HIV-infected rural Ugandans is high. These data suggest that liver disease may represent a significant cause of HIV-related morbidity and mortality in Africa.
Le second ordre de la politique économique
Authors: Villa Pierre 
Published: May 2011

Résumé On propose une formalisation de la politique mixte en partant des apports de la finance moderne : actifs dérivés, titrisation (hybridation), nantissement. La dette et les fonds propres sont des options de vente et d’achat d’actifs réels dont le prix suit un processus non logarithmique qui peut être calculé comme une solution avant (fondamentalisme) ou arrière (chartisme). La décision de faillite est l’exercice d’une option dont le nantissement est la valeur d’exercice. La titrisation optimale de la dette publique pour les intermédiaires financiers égalise les coûts marginaux de faillite par rapport à la dette publique et aux actifs réels. Le profit des intermédiaires accroît le coût d’usage du capital. La politique monétaire contrôle le coût de l’intermédiation par le taux d’intérêt, le risque macroéconomique en fixant un objectif intermédiaire de titrisation de la dette publique et garantit cette dernière par le refinancement de la part non titrisée. L’éligibilité et le nantissement du refinancement sont fixés par une agence publique de notation. Une politique coordonnée à moyen et court terme est proposée pour une zone monétaire. Le coefficient de garantie des actifs permet de distinguer les interventions du prêteur en dernier ressort en période normale et de crise.