bluuebunny/crossref_metadata_2025_split huggingface dataset:
The Effects of Prolonged Acute Hypobaric Hypoxia on Novel Measures of Biventricular Performance
Authors: Boos Christopher J. , Hodkinson Pete D. , Mellor Adrian , Green Nick P. , Bradley Daniel , Greaves Kim , Woods David R. 
Published: January 2013

BackgroundThere are limited data on the effects of prolonged acute hypoxia on individual and global measures of biventricular function.AimsThe aim of this study was to assess its effects on conventional and novel measures of biventricular function, including the recently defined E′/(A′×S′) (EAS) index, obtained using pulsed‐wave tissue Doppler Imaging (PWTDI) and associated blood brain natriuretic peptide (BNP) levels.MethodsIn this study, 14 healthy subjects aged 30.5 years were assessed at baseline and at >150 minutes following hypobaric hypoxia (HH) to the equivalent altitude of 4800 m for a total of 180 minutes. The combined EAS index (E′/(A′ × S′)) was calculated at the mitral and tricuspid annulus using data from the peak systolic (S′) early (E′) and late (A′) diastolic filling.ResultsIt was seen that HH increased resting heart rate (63.4 ± 8.4 vs. 85.2 ± 10.2/min; P < 0.0001), cardiac output (4.6 ± 0.7 L/min vs. 6.1 ± 1.2 L/min; P < 0.0001), peak pulmonary artery systolic pressure (PASP) (26.3 ± 2.0 mmHg vs. 37.2 ± 6.3 mmHg; P < 0.0001), and reduced SpO2 (98.5 ± 1.1 vs. 72.9 ± 8.1%; P < 0.0001). There was a significant reduction in mitral (0.19 ± 0.06 vs. 0.11 ± 0.03; P < 0.0001) and tricuspid (0.12 ± 0.04 vs. 0.09 ± 0.03; P = 0.03) EAS indices, but no change in left or right ventricular myocardial performance (Tei) indices, global left ventricular (LV) longitudinal systolic strain, BNP levels, or estimated filling pressures (E/E′). Only reducing SpO2 remained as an independent predictor of PASP on multivariate analysis (overall R2 = 0.77; P < 0.0001). The right and LV EAS indices were significantly correlated (r = 0.45; 95% CI: 0.07–0.7; P = 0.02).ConclusionThe conclusion from this study was that acute prolonged HH does not adversely affect resting global biventricular function and there is evidence of linked right and LV responses.
Left Atrial Deformation Parameters Predict Left Atrial Appendage Function and Thrombus in Patients in Sinus Rhythm with Suspected Cardioembolic Stroke: A Speckle Tracking and Transesophageal Echocardiography Study
Authors: Karabay Can Yücel , Zehir Regayip , Güler Ahmet , Oduncu Vecih , Kalayci Arzu , Aung Soe Moe , Karagoz Ali , Tanboga Ibrahim Halil , Candan Ozkan , Gecmen Cetin , Erkol Ayhan , Esen Ali Metin , Kirma Cevat 
Published: January 2013

The aim of this study was to evaluate left atrial deformations using speckle tracking echocardiography for predicting left atrial appendage (LAA) thrombus in patients with suspected cardioembolic stroke who were in normal sinus rhythm. A total of 153 ischemic stroke patients (89 males, 64 females) in sinus rhythm who were suspected of having cardioembolism were included in the study. The patients underwent conventional two‐dimensional (2D) echocardiogram and 2D speckle tracking echocardiogram of the left atrium. Left atrial peak strain (LA‐4C‐RES) and left atrial precontraction strain (LA‐4C‐PUMP) were measured. Patients were divided into 2 groups according to the presence of thrombus in the LAA in transesophageal echocardiography. Both LA‐4C‐RES and LA‐4C‐PUMP values were found to be significantly lower in patients with LAA thrombus (11.8 ± 1.4% vs. 33 ± 12%, P < 0.001 and 5.8 ± 1.3% vs. 14.2 ± 5.3%, P < 0.001, respectively). A good inverse correlation was present between LA‐4C‐RES values and LAA morphologic parameters (with LAA area: r = −0.70, P < 0.001, with LAA length: r = −0.60, P < 0.001), and a good positive correlation was present with LAA emptying velocity with pulse Doppler (r = 0.74, P < 0.001). The area under the receiver‐operating characteristic curve of the LA‐4C‐RES was 0.94 (0.90–0.98, P < 0.001), for the LA‐4C‐PUMP, the area was 0.92 (0.87–0.96, P < 0.001) to predict LAA thrombus. Left atrial deformation parameters measured by 2D speckle tracking method was found to predict impaired LAA functions and the presence of LAA thrombus in ischemic stroke patients with suspected cardioembolism, but who are in sinus rhythm.
Aortopulmonary Artery Fistula: Ruptured Aneurysm of the Distal Aortic Arch into the Pulmonary Artery
Authors: Sasaki Osamu , Nishioka Toshihiko , Inoue Yoshiro , Sasaki Hideki , Ito Hiroyuki , Yoshimoto Nobuo 
Published: January 2013

Aortopulmonary artery fistula is uncommon, but the clinical outcome is often lethal. A 76‐year‐old man with a history of acute thoracic aortic dissection 6 years previously was admitted with dyspnea. A chest x‐ray showed pleural effusion and pulmonary congestion. Transthoracic echocardiography revealed preserved systolic function, but continuous and abnormal flow from the distal aortic arch into the pulmonary artery (PA). Transesophageal echocardiography (TEE) in the Doppler color‐flow mode demonstrated a left‐to‐right shunt between a large distal aortic arch aneurysm and the left PA via an aortopulmonary fistula and a pressure gradient across the shunt of 56 mmHg. Contrast‐enhanced computed tomography showed that the aneurysm compressed the PA. Aortography also revealed a large distal aortic arch aneurysm and almost simultaneous contrast enhancement of the aorta and the PA. Right‐heart catheterization showed a significant increase in oxygen saturation between the right ventricle and the PA. A left‐to‐right shunt due to a distal aortic arch aneurysm rupturing into the left PA was diagnosed based on these findings. TEE was very helpful in confirming the presence and precise location of the fistula.
Effects of the HeartMate II Left Ventricular Assist Device as Observed by Serial Echocardiography
Authors: Chapman Carrie B. , Allana Salman , Sweitzer Nancy K. , Kohmoto Takushi , Murray Margaret , Murray David , Johnson Maryl , Rahko Peter S. 
Published: January 2013

BackgroundThe HeartMate II is the most frequently used left ventricular assist device (LVAD) in patients with end‐stage heart failure. There is a paucity of data regarding its longitudinal cardiac effects, particularly that on diastole.MethodsThis retrospective study was an evaluation of echocardiograms preoperatively and at 3, 6, and 12 months postoperatively in patients with a HeartMate II. Measurements included left ventricle (LV) dimensions, ejection fraction (EF), right ventricle (RV) size and function, parameters of diastolic function, and an analysis of mitral regurgitation (MR), tricuspid regurgitation (TR), aortic insufficiency (AI), and aortic valve thickening.ResultsForty‐seven patients were evaluated. LV dimensions decreased but EF, RV size, and RV function were unchanged. Right ventricular systolic pressure (RVSP) and diastolic parameters including mitral inflow E/A, deceleration time (DT), pulmonary vein inflow, left atrial size, and overall diastolic grade improved. LV relaxation measured by tissue Doppler (e') was unchanged and the E/e' ratio was also unchanged. Regarding valve function, MR decreased, TR was unchanged, and the aortic valve became increasingly thickened with increased AI severity.ConclusionsThe HeartMate II unloads the LV as shown by decreased LV size, decreased MR, reduced RVSP, and improved patterns of mitral inflow. However, neither systolic function nor diastolic relaxation improves in this cohort. RV size and function also remain unchanged. The aortic valve shows increased thickening and AI likely from valve leaflet fusion. These results provide detailed functional and hemodynamic information regarding the longitudinal effects of the HeartMate II.
Detection of Early Left Ventricular and Atrial Dysfunction in Overweight Patients with Preserved Ejection Fraction: A Speckle Tracking Analysis
Authors: Caputo Maria , Urselli Rossella , Zacà Valerio , Capati Eugenia , Padeletti Margherita , De Nicola Silvia , Navarri Romina , Antonelli Giovanni , Nucci Claudia , Giacomin Elisa , Mondillo Sergio 
Published: January 2013

BackgroundLittle remains known about the role of overweight to promote progressive atrial and ventricular myocardial dysfunction. Aim of this study was to investigate the potential influence of overweight on left ventricular (LV) and atrial (LA) function, as assessed by speckle tracking strain analysis, in patients at low‐to‐moderate global cardiovascular risk.MethodsSeventy patients presenting 1 or more cardiovascular risk factor, with preserved ejection fraction, were enrolled. Peak atrial longitudinal strain (PALS) and Peak ventricular longitudinal strain (PVLS) were calculated by averaging values observed in all LV or LA segments, in four‐ and two‐chamber views (global PALS and global PVLS), using a commercially available semiautomated two‐dimensional (2D) strain software.ResultsGlobal PALS was similar in the 2 groups, while global PVLS was significantly lower in the overweight group as compared to normal weight (−17.2 ± 3.3 vs. −18.7 ± 2.8, P < 0.05). Univariate analysis of correlation showed a significantly correlation between global PALS and PVLS (r = −0.43, P < 0.01), as well as with E/A ratio (r = 0.40, P < 0.01) and with LV mass index (r = −0.34, P < 0.05). In multivariate linear regression analysis, these parameters were confirmed as independent predictors of PALS.ConclusionIn subjects at low‐to‐moderate cardiovascular risk, overweight is a key determinant of the reduction of global LV longitudinal function as assessed by 2D strain.
Altered Coronary Flow Velocity Reserve and Left Ventricular Wall Motion Dynamics: A Phenomenon in Hypertensive Patients with ECG Strain
Authors: Arita Yu , Hirata Kumiko , Wada Nozomi , Komukai Kenichi , Tanimoto Takashi , Kitabata Hironori , Takarada Shigeho , Nakamura Nobuo , Kubo Takashi , Tanaka Atsushi , Imanishi Toshio , Akasaka Takashi 
Published: January 2013

BackgroundThe inner‐half layer of the left ventricular (LV) wall is primarily affected by ischemia and increased LV afterload. We hypothesized that LV wall thickening of inner‐half layer and coronary microvascular function are impaired in hypertensive patients, especially in those with electrocardiographic (ECG) strain, which is a marker of LV hypertrophy and adverse prognosis. Therefore, the aim of this study is to investigate the association of the ratio of inner‐ to outer‐half layer of the LV myocardial deformation and coronary microvascular function with ECG strain in hypertensive patients.MethodsWe studied 98 hypertensive patients and 13 controls. Hypertensive patients were divided into 2 groups, with (S+) and without (S−) ECG strain. Coronary flow velocity reserve (CFVR) of the left anterior descending artery was evaluated using transthoracic echocardiography. Circumferential and radial strains of the LV wall were analyzed by two‐dimensional echocardiographic speckle tracking method, and the inner‐ to outer‐half layer ratio (in/out ratio) was assessed.ResultsCoronary flow velocity reserve of S+ (2.06 ± 0.65) was significantly smaller than those in S− and controls (3.03 ± 0.65 and 3.38 ± 0.51, respectively). In/out ratio in both circumferential and radial strains were decreased as well as in S+ patients. Furthermore, in/out ratio was directly proportional to CFVR.ConclusionsHypertensive patients with ECG strain possessed severely impaired CFVR and inner‐half myocardial deformation. Moreover, the more severe the LV hypertrophy progresses, the greater is the impairment of coronary microvascular and LV inner‐half myocardial deformation. Thus, CFVR and in/out ratio are useful quantitative markers that can render sensitive assessment of physiological changes in hypertensive heart disease.
Cardiovascular Magnetic Resonance as an Alternate Method for Serial Evaluation of Proximal Aorta: Comparison with Echocardiography
Authors: Bhatla Puneet , Nielsen James C 
Published: January 2013

Thoracic aortic disease is a known cause of aortic dilatation and poses significant risk of aortic dissection and rupture. Serial assessment of aortic root dimensions is traditionally performed using echocardiography, which is limited with older age and following surgery, due to poor acoustic windows. Although diastolic measurements are utilized as standard practice in decision making of adult aortopathy, systolic diameters are utilized in pediatric practice. Three‐dimensional steady‐state free precision (3D‐SSFP) has shown promise as an alternate method for providing accurate and reproducible aortic measurements. The agreement between proximal aorta measurements by diastolic 3D‐SSFP and echocardiography (both systole and diastole) was examined in 40 subjects. The maximum inner diameters at aortic annulus, root and sinotubular junction demonstrated excellent agreement between 3D‐SSFP and echocardiography for all the 3 levels. The best agreement was observed for diastolic root dimensions with a mean difference of +0.01 cm, limits of agreement being −0.26 to +0.28 cm. Three D‐SSFP can be used interchangeably with echocardiography in the serial assessment of the aortic root size. Careful attention to obtain an imaging plane utilizing 3D multiplanar reformatting is critical to maximize the agreement between the two imaging modalities.
Paraaortic Thymoma with Pericardial Effusion Diagnosed by Transthoracic Echocardiography in a Woman with Myasthenia Gravis
Authors: Santoro Francesco , Russo Anna Rita , Lupo Pierluigi , De Gennaro Luisa , Gianfrancesco Domenico , Biase Matteo Di , Brunetti Natale Daniele 
Published: January 2013

Mini‐AbstractWe report the case of a 64‐year‐old woman with myasthenia gravis, dyspnea, and pericardial effusion. Echocardiography showed a paraaortic mass, confirmed at computed tomography scan, which was later diagnosed as a thymoma after surgical excision.
Resistance to vertical fracture of MTA‐filled roots
Authors: EL‐Ma'aita Ahmad M. , Qualtrough Alison J. E. , Watts David C. 
Published: January 2013

AbstractAimTo investigate the effect of MTA root canal fillings on the resistance to vertical root fracture (VRF) over different time intervals.Material and methodsFreshly extracted anterior human teeth with single canals and minimal curvatures were decoronated, instrumented to size 50/.05 ProTaper file, irrigated with 1%NaOCl and randomly allocated to one of three groups (n = 36): (i) filled with MTA, (ii) filled with gutta‐percha and sealer and (iii) unfilled roots used as a negative control. Each group was subdivided into three subgroups (n = 12) according to the storage time of 48 h, 1 and 6 months at 37°C in synthetic tissue fluid (STF). Following the storage periods, filled roots were mounted in acrylic supports, and the periodontal ligament was simulated using elastomeric impression material. Vertical loading was carried out with a ball‐ended steel cylinder fitted on a universal testing machine at 1 mm/min crosshead speed. The maximum force at fracture (F‐max) and the fracture mode were recorded for each root.ResultsData were statistically analysed using two‐way anova and Bonferroni post hoc tests. The mean F‐max was significantly higher in the MTA subgroups after 1 and 6 months compared with all other subgroups. Two modes of fracture were identified: split and comminuted. The mean F‐max values recorded with the latter were significantly higher compared with the former (P < 0.001). In all groups, split fracture was the most dominant mode apart from the MTA/1 month and MTA/6 month groups.ConclusionMTA increases the resistance to VRF of endodontically treated teeth and influences the mode of fracture after 1 and 6 month of storage in STF compared with gutta‐percha and sealer.
Soft skills and dental education
Authors: Gonzalez M. A. G. , Abu Kasim N. H. , Naimie Z. 
Published: January 2013

AbstractSoft skills and hard skills are essential in the practice of dentistry. While hard skills deal with technical proficiency, soft skills relate to a personal values and interpersonal skills that determine a person's ability to fit in a particular situation. These skills contribute to the success of organisations that deal face‐to‐face with clients. Effective soft skills benefit the dental practice. However, the teaching of soft skills remains a challenge to dental schools. This paper discusses the different soft skills, how they are taught and assessed and the issues that need to be addressed in their teaching and assessment. The use of the module by the Faculty of Dentistry, University of Malaya for development of soft skills for institutions of higher learning introduced by the Ministry of Higher Education, Malaysia.
The proteasome inhibitor bortezomib stimulates osteoblastic differentiation of human osteoblast precursors via upregulation of vitamin D receptor signalling
Authors: Kaiser Martin F. , Heider Ulrike , Mieth Maren , Zang Chuanbing , von Metzler Ivana , Sezer Orhan 
Published: January 2013

AbstractInteractions of myeloma cells with the bone marrow microenvironment lead to enhanced osteoclast recruitment and impaired osteoblast activity. Recent evidence revealed that the proteasome inhibitor bortezomib stimulates osteoblast differentiation, but the mechanisms are not fully elucidated. We hypothesised that bortezomib could influence osteoblastic differentiation via alteration of vitamin D signalling by blocking the proteasomal degradation of the vitamin D receptor (VDR). This is of clinical importance, as a high rate of vitamin D deficiency was reported in patients with myeloma. We performed cocultures of primary human mesenchymal stem cells (hMSCs) and human osteoblasts (hOBs) with myeloma cells, which resulted in an inhibition of the vitamin D‐dependent differentiation of osteoblast precursors. Treatment with bortezomib led to a moderate increase in osteoblastic differentiation markers in hMSCs and hOBs. Importantly, this effect could be strikingly increased when vitamin D was added. Bortezomib led to enhanced nuclear VDR protein levels in hMSCs. Primary hMSCs transfected with a VDR luciferase reporter construct showed a strong increase in VDR signalling with bortezomib. In summary, stimulation of VDR signalling is a mechanism for the bortezomib‐induced stimulation of osteoblastic differentiation. The data suggest that supplementation of vitamin D in patients with myeloma treated with bortezomib is crucial for optimal bone formation.
Stroke recurrence in patients with recently symptomatic carotid stenosis and scheduled for carotid revascularization
Authors: Al‐Khaled M. , Awwad H. , Matthis C. , Eggers J. 
Published: January 2013

Background and purposePatients with symptomatic carotid stenosis (sCS) have a higher risk of stroke recurrence following the first ischaemic event. Guidelines recommend that patients undergo carotid revascularization (CR), preferably within 2 weeks of the event. We aimed to determine the rate of stroke recurrence during hospitalization in patients who were admitted to the hospital with an acute ischaemic event and who underwent CR for recently sCS.MethodsAs part of the stroke registry in Schleswig‐Holstein, Germany (QugSS2; Qualitätsgemeinschaft Schlaganfallversorgung in Schleswig‐Holstein), over a 4.5‐year period (starting 2007) all patients (N = 15 797) who were admitted to the hospital with an acute cerebral ischaemic event were included and prospectively evaluated.ResultsA total of 597 (3.8%) patients (mean age, 71 ± 10 years; 30% women) underwent a CR. The median time between symptom onset and admission to hospitals was 6 h. During the mean hospitalization of 10 days, 30 patients (5%) suffered a stroke. The rates of stroke recurrence were higher, albeit non‐significantly, in men compared with women (6% vs. 2.3%, respectively; P = 0.059), and in patients admitted with ischaemic stroke compared with patients admitted with transient ischaemic attack (6.1% vs. 2%, respectively; P = 0.052). The risk of stroke recurrence did not show any association with the other demographic and clinical parameters.ConclusionThe rate of stroke recurrence was 5% in patients with recently sCS who scheduled for CR. This suggests that CR should be performed immediately after presenting event to prevent stroke recurrence.
Spinal cord injury: association with axonal peripheral neuropathy in severely paralysed limbs
Authors: Kamradt T. , Rasch C. , Schuld C. , Böttinger M. , Mürle B. , Hensel C. , Fürstenberg C. H. , Weidner N. , Rupp R. , Hug A. 
Published: January 2013

Background and purposePressure sores are a major health problem in spinal cord injury (SCI). In this population pressure damage to peripheral nerves was not thoroughly investigated so far. However, intact peripheral nerves and innervated muscles are a prerequisite for the effectiveness of supportive therapies like functional electrical stimulation (FES).MethodsWe assessed electroneurographic (ENG) data of lower limbs in SCI individuals admitted to our hospital due to severe pressure sores. Our centers prospectively acquired ENG data of the European Multicenter study about SCI (EMSCI) patients served as early control.ResultsIn the pressure sore cohort (n = 15) all patients were sensory‐motor complete (American Spinal Cord Injury Association Impairment Scale A). Most patients (10/15) suffered from a severe axonal sensory‐motor polyneuropathy in paralysed legs with absent compound muscle action potentials (CMAPs) of tibial/peroneal nerves as well as absent sensory nerve action potentials of sural nerves. The onset of this polyneuropathy dates within the first year after incident SCI and was mainly associated with increasing sensory‐motor completeness as demonstrated by a significant CMAP drop of our centers EMSCI‐ENG data on serial tibial nerve recordings in 275 patients.ConclusionsSevere SCI is associated with an early‐onset axonal polyneuropathy in paralysed limbs to which pressure damage might contribute. Because intact peripheral nerves are required for: (i) maintenance of motor function in centrally impaired muscles; and (ii) effectiveness of supportive therapies like FES, ENG‐monitoring could serve as a low invasive screening method for peripheral nerve integrity in patients with SCI to initiate pressure relief procedures early enough.
Distribution of polyethylene glycol coated quantum dots in mice skin
Authors: Kulvietis Vytautas , Zurauskas Edvardas , Rotomskis Ricardas 
Published: January 2013

AbstractThe distribution of nanoparticles (NP) in an organism is an important issue for developing NP–based drug delivery systems and for general nanotoxicology. The knowledge of NP localisation in the skin is crucial for the optimisation of NP behaviour in vivo. Therefore, we have used semiconductor quantum dots (QD) to investigate their biodistribution in the skin by means of confocal fluorescence microscopy after subcutaneous injection. The results obtained showed that the diffusion of QD in the dermis is limited by basement membrane and dense connective tissue fibres, which resulted in negligible QD penetration into the epidermis, hair follicles, sebaceous and sweat glands, nerves and blood vessels. Low permeation of QD through the tissues results in slow clearance and raises the risks of potential immune, inflammatory and cytotoxic responses. The study reveals the significance of the tissue architecture for the interstitial and intracellular migration patterns of non‐functionalised QD.