bluuebunny/crossref_metadata_2025 huggingface dataset:
Myocardial Infarction and Atrial Fibrillation
Authors: Alasady Muayad , Shipp Nicholas J. , Brooks Anthony G. , Lim Han S. , Lau Dennis H. , Barlow David , Kuklik Pawel , Worthley Matthew I. , Roberts-Thomson Kurt C. , Saint David A. , Abhayaratna Walter , Sanders Prashanthan
Published: July 2013

Background—

Myocardial infarction (MI) is associated with the development of atrial fibrillation (AF). We aimed to characterize the atrial abnormalities because of MI and determine the role of ischemia to the AF substrate.

Methods and Results—

Forty-four sheep were studied. MI was induced by occlusion of the left circumflex artery (LCX) or left anterior descending artery (LAD). Excluding 11 with fatal arrhythmias, equal groups of animals (LCX; LAD; and sham-operated) underwent sequential electrophysiology study for 45 minutes to determine atrial effective refractory periods, conduction velocity, conduction heterogeneity index, and AF inducibility. Postmortem evaluation was performed with 2,3,5 triphenyl tetrazolium chloride staining. MI resulted in greater left ventricular dysfunction (
P
<0.05), LA pressure (
P
<0.0003), and reduction in atrial effective refractory periods (
P
<0.0001) compared with control. 2,3,5 triphenyl tetrazolium chloride staining demonstrated that the left circumflex artery, and not the LAD, group had atrial infarction. The left circumflex artery group demonstrated the following compared with the LAD or control groups: greater slowing in atrial conduction velocity (
P
<0.0001 and
P
<0.001); increased absolute range of conduction phase delay (
P
<0.001 and
P
<0.001); increased conduction heterogeneity index (
P
<0.0001 and
P
<0.001); greater AF vulnerability (
P
<0.05 for both); and longer AF duration (
P
<0.05 for both). LAD group had modest but significant slowing in conduction velocity (
P
<0.01) but no change in conduction heterogeneity index or AF duration compared with control.

Conclusions—

Left ventricular infarction, which is known to result in atrial stretch, hemodynamic change, and neurohumoral activation, contributes partially to the atrial abnormalities in MI. Atrial ischemia/infarction results in greater atrial electrophysiological changes and propensity for AF forming the dominant substrate for AF in MI.
Low Heart Rates Predict Incident Atrial Fibrillation in Healthy Middle-Aged Men
Authors: Grundvold Irene , Skretteberg Per Torger , Liestøl Knut , Erikssen Gunnar , Engeseth Kristian , Gjesdal Knut , Kjeldsen Sverre E. , Arnesen Harald , Erikssen Jan , Bodegard Johan
Published: July 2013

Background—

Low resting heart rate (HR) has been associated with atrial fibrillation (AF) in athletes. We aimed to study whether low HR at rest or during exercise testing was a predictor of AF in initially healthy middle-aged men.

Methods and Results—

A total of 2014 healthy Norwegian men participated in a prospective cardiovascular survey, including a standardized bicycle exercise test in 1972 to 1975. During ≤35 years of follow-up (53 000 person-years of observation), 270 men developed incident AF, documented by scrutiny of health charts in all Norwegian hospitals. Risk estimation was analyzed with Cox proportional hazard models. Low exercise HR after 6 minutes exercise on the moderate workload of 100 W (HR100W) was a predictor of incident AF. Men with HR100W <100 beats per minute (n=260) were characterized by high physical fitness, low resting and low maximum HR, and they had 1.60-fold AF risk (95% confidence interval, 1.11–2.26) compared with men with HR100W ≥100 beats per minute when adjusted for age, systolic blood pressure, and physical fitness. Additional adjustment for relative heart volume slightly reduced the association. The subgroup of men (n=860) with hypertensive blood pressure measurements at baseline had the highest risk difference between low and high HR100W with hazard ratio 2.08 (1.19–3.45).

Conclusions—

Our data indicate that low exercise HR on a moderate workload is a long-term predictor of incident AF in healthy middle-aged men. Elevated baseline blood pressure substantially amplifies this risk. The present results suggest a relationship between increased vagal tone, high stroke volumes and incident AF, and particularly so in physically fit men.
Incremental His-To-Coronary Sinus Maneuver
Authors: Vallès Ermengol , Bazán Victor , Benito Begoña , Jáuregui Miguel Eduardo , Bruguera Jordi , Guijo Miguel Angel , Altaba Carmen , Martí-Almor Julio
Published: July 2013

Background—

Achievement of complete cavotricuspid isthmus (CTI) conduction block reduces typical atrial flutter recurrences after ablation. The lack of increase in the His-to-Coronary sinus ostium atrial interval during incremental pacing (IP) from the low lateral right atrium may distinguish slow conduction from complete CTI conduction block.

Methods and Results—

Sixty-six consecutive patients (age, 65±13 years; 18% female) were prospectively included. A <10 ms increase in the His-to-Coronary sinus ostium atrial timing during low lateral right atrium IP at cycle length of 600 ms through 300 ms was compared with the previously reported IP maneuver for the confirmation of complete CTI block. On the basis of the IP maneuver, complete CTI block (phase 2) was achieved in 59 patients, in 13 of whom an intermediate phase of functional CTI block (phase 1) was observed. In the remaining 7 patients, the IP maneuver did not allow for assessment of complete CTI block because of the presence of inconclusive potentials in the CTI ablation line. As compared with the IP maneuver, the incremental His-to-Coronary sinus ostium maneuver was consistent with functional CTI block during phase 1 in all cases and conclusive of complete CTI block in 98% of cases during phase 2.

Conclusions—

The incremental His-to-Coronary sinus ostium maneuver is analogous to the IP maneuver in distinguishing complete CTI block from persistent CTI conduction. This maneuver may provide confirmation of CTI block in those patients in whom assessment of local electrogram–based criteria is not feasible because of inconclusive potentials in the CTI ablation line.
Electrical Homogenization of Ventricular Scar by Application of Collagenase
Authors: Yagishita Daigo , Ajijola Olujimi A. , Vaseghi Marmar , Nsair Ali , Zhou Wei , Yamakawa Kentaro , Tung Roderick , Mahajan Aman , Shivkumar Kalyanam
Published: July 2013

Background—

Radiofrequency ablation for ventricular tachycardia is an established therapy. Use of chemical agents for scar homogenization represents an alternative approach. The purpose of this study was to characterize the efficacy of collagenase (CLG) application on epicardial ventricular scar homogenization.

Methods and Results—

Myocardial infarcts were created in Yorkshire pigs (n=6) by intracoronary microsphere injection. After 46.6±4.3 days, CLG type 2, type 4, and purified CLG were applied in vitro (n=1) to myocardial tissue blocks containing normal myocardium, border zone, and dense scar. Histopathologic studies were performed to identify the optimal CLG subtype. In vivo high-density electroanatomic mapping of the epicardium was also performed, and border zone and dense scar surface area and late potentials were quantified before and after CLG-4 application (n=5). Of the CLG subtypes tested in vitro, CLG-4 provided the best scar modification and least damage to normal myocardium. During in vivo testing, CLG-4 application decreased border zone area (21.3±14.3 to 17.1±11.1 mm
2
,
P
=0.043) and increased dense scar area (9.1±10.3 to 22.0±20.6 mm
2
,
P
=0.043). The total scar area before and after CLG application was 30.4±23.4 and 39.2±29.5 mm
2
, respectively (
P
=0.08). Late potentials were reduced by CLG-4 application (28.8±21.8 to 13.8±13.1,
P
=0.043). During CLG-4 application (50.0±15.5 minutes), systolic blood pressure and heart rate were not significantly changed (68.0±7.7 versus 61.8±5.3 mmHg,
P
=0.08; 77.4±7.3 versus 78.8±6.0 beats per minute,
P
=0.50, respectively).

Conclusions—

Ventricular epicardial scar homogenization by CLG-4 application is feasible and effective. This represents the first report on bioenzymatic ablation of arrhythmogenic tissue as an alternative strategy for lesion formation.
The Role of Implantable Cardioverter-Defibrillators in Patients With Continuous Flow Left Ventricular Assist Devices
Authors: Enriquez Alan D. , Calenda Brandon , Miller Marc A. , Anyanwu Anelechi C. , Pinney Sean P.
Published: July 2013

Background—

The prognosis for patients experiencing ventricular arrhythmias (VAs) while on continuous flow left ventricular assist device (LVAD) support has not been well elucidated. Accordingly, the role of implantable cardioverter-defibrillators (ICDs) in this patient population remains undefined.

Methods and Results—

Records of 106 consecutive patients undergoing implantation of the HeartMate II LVAD at a single center were reviewed. For patients surviving >30 days postimplant (98 patients), the impact of VAs and ICDs on survival was analyzed. Mean age was 56.6±11.4 years, 82.1% were male, 42.5% had an ischemic cardiomyopathy, 87.7% were bridge to transplantation, and median length of support was 217 days. Twenty-one (19.8%) patients died, 60 (56.6%) survived to transplantation, and 25 patients (23.6%) reached the end of study, had the LVAD explanted, or were lost to follow-up. Post-LVAD VAs occurred in 37 patients (34.9%) but were not associated with increased mortality (hazard ratio, 0.58 [0.18–1.90]). Sixty-two (63.3%) patients had an active ICD, and 36 (36.7%) patients had no ICD or an inactivated ICD post-LVAD. Patients with an ICD were more likely to be INTERMACS (Interagency Registry for Mechanically Assisted Circulatory Support) level 3 or 4 at the time of implant (54.8% versus 33.3%;
P
=0.04). An appropriate shock was delivered in 27.3% of patients, but the presence of an active ICD was not associated with improved survival (hazard ratio, 1.12 [0.37–3.35]).

Conclusions—

VAs are common in patients with continuous flow LVADs. Although some episodes may be clinically significant, VAs are not associated with a worse prognosis, and concomitant ICDs in these patients may not reduce mortality.
Locations of High Contact Force During Left Atrial Mapping in Atrial Fibrillation Patients
Authors: Nakagawa Hiroshi , Kautzner Josef , Natale Andrea , Peichl Petr , Cihak Robert , Wichterle Dan , Ikeda Atsushi , Santangeli Pasquale , Di Biase Luigi , Jackman Warren M.
Published: July 2013

Background—

During radiofrequency ablation, high electrode-tissue contact force (CF) is associated with increased risk of steam pop and perforation. The purpose of this study, in patients undergoing ablation of paroxysmal atrial fibrillation, was to: (1) identify factors producing high CF during left atrial (LA) and pulmonary vein mapping; (2) determine the ability of atrial potential amplitude and impedance to predict CF; and (3) explore the feasibility of controlling radiofrequency power based on CF.

Methods and Results—

A high-density map of LA/pulmonary veins (median 328 sites) was obtained in 18 patients undergoing atrial fibrillation ablation using a 7.5-Fr irrigated mapping/ablation catheter to measure CF. Average CF was displayed on the 3D map. For 5682 mapped sites, CF ranged 1–144 g (median 8.2 g). High CF (≥35 g) was observed at only 118/5682 (2%) sites, clustering in 6 LA regions. The most common high CF site (48/113 sites in 17/18 patients) was located at the anterior/rightward LA roof, directly beneath the ascending aorta (confirmed by merging the CT image and map). Poor relationship between CF and either unipolar amplitude, bipolar amplitude, or impedance was observed. During ablation, radiofrequency power was modulated based on CF. All pulmonary veins were isolated without steam pop, impedance rise, or pericardial effusion.

Conclusions—

High CF often occurs at anterior/rightward roof, where the ascending aorta provides resistance to the LA. Atrial potential amplitude and impedance are poor predictors of CF. Controlling radiofrequency power based on CF seems to prevent steam pop and impedance rise without loss of lesion effectiveness.
Cardiorespiratory Fitness, Body Mass Index, and Heart Failure Mortality in Men
Authors: Farrell Stephen W. , Finley Carrie E. , Radford Nina B. , Haskell William L.
Published: July 2013

Background—

We evaluated the individual and joint associations among cardiorespiratory fitness (CRF), body mass index, and heart failure (HF) mortality, as well as the additive effect of an increasing number of cardiovascular risk factors on HF mortality in fit versus unfit men.

Methods and Results—

A total of 44 674 men without a history of cardiovascular disease underwent a baseline examination between 1971 and 2010. Measures included body mass index and CRF quantified as duration of maximal treadmill exercise testing. Participants were divided into age-specific low, moderate, and high CRF categories. Hazard ratios were computed with Cox regression analysis. During a mean follow-up of 19.8±10.4 years, 153 HF deaths occurred. Adjusted hazard ratios across high, moderate, and low CRF categories were 1.0, 1.63, and 3.97, respectively, whereas those of normal, overweight, and obese body mass index categories were 1.0, 1.56, and 3.71, respectively (
P
for trend <0.0001 for each). When grouped into categories of fit and unfit (upper 80% and lower 20% of CRF distribution, respectively), hazard ratios were significantly lower in fit compared with unfit men in normal and overweight body mass index strata (
P
<0.002) but not in obese men. Within men matched for the same number of HF risk factors, fit men had significantly lower HF mortality than unfit men (
P
≤0.02).

Conclusions—

Higher baseline CRF is associated with lower HF mortality risk in men, regardless of the number of HF risk factors present. Men should be counseled on physical activity with the goal of achieving at least a moderate level of CRF, thereby presumably decreasing their risk of HF mortality.
The COP9 Signalosome Is Required for Autophagy, Proteasome-Mediated Proteolysis, and Cardiomyocyte Survival in Adult Mice
Authors: Su Huabo , Li Jie , Osinska Hanna , Li Faqian , Robbins Jeffrey , Liu Jinbao , Wei Ning , Wang Xuejun
Published: July 2013

Background—

The COP9 signalosome (CSN) is an evolutionarily conserved protein complex composed of 8 unique protein subunits (CSN1 through CSN8). We have recently discovered in perinatal mouse hearts that CSN regulates not only proteasome-mediated proteolysis but also macroautophagy. However, the physiological significance of CSN in a post-mitotic organ of adult vertebrates has not been determined. We sought to study the physiological role of CSN8/CSN in adult mouse hearts.

Methods and Results—

Csn8

was conditionally ablated in the cardiomyocytes of adult mice (CSN8
CKO
) using a temporally controlled Cre-LoxP system. Loss of CSN8 accumulated the neddylated forms of cullins and noncullin proteins, increased ubiquitinated proteins, and stabilized a surrogate substrate of the proteasome in the heart. Autophagic flux was significantly decreased, whereas autophagosomes were markedly increased in CSN8
CKO
hearts, indicative of impaired autophagosome removal. Furthermore, we observed increased oxidized proteins, massive necrotic cardiomyocytes, and morphological and functional changes characteristic of dilated cardiomyopathy in CSN8
CKO
mice.

Conclusions—

CSN deneddylates substrates more than cullins and is indispensable to cardiomyocyte survival in not only perinatal hearts but also adult hearts. CSN8/CSN regulates both proteasome-mediated proteolysis and the autophagic-lysosomal pathway, critical to the removal of oxidized proteins in the heart.
Cardiovascular Magnetic Resonance Characteristics in Children With Hypertrophic Cardiomyopathy
Authors: Chaowu Yan , Shihua Zhao , Jian Ling , Li Li , Wei Fang
Published: July 2013

Background—

Cardiovascular magnetic resonance has provided important information on the diagnosis and risk stratification of hypertrophic cardiomyopathy (HCM) in adults; however, comparable data are absent for HCM in children. The study was performed to evaluate cardiovascular magnetic resonance characteristics in children with idiopathic HCM.

Methods and Results—

Cardiovascular magnetic resonance was performed in 71 consecutive children with idiopathic HCM (age, 12.8±4.1 years; 46 boys and 25 girls). The left ventricular (LV) parameters indexed by body surface area were calculated and compared with those in 71 healthy children (age, 13.1±3.3 years; 51 boys and 20 girls). Among those with HCM, concentric LV hypertrophy occurred in 9 patients (12.7%): in 2 children, it progressed into end-stage phase. The prevalence of late gadolinium enhancement (LGE) was 73%, and the extent of LGE was 10.4±8.3% of LV mass. Children with HCM with LGE had greater LV mass indexed (112.7±57.9 versus 70.3±37.4 g/m
2
;
P
=0.025) but had no significant difference in maximal LV wall thickness indexed (19.4±6.3 versus 18.1±7.9 mm/m
2
;
P
=0.513). In addition, the hazard ratio of adverse events for the extent of LGE was 1.1 (
P
=0.004). The follow-up (2.4±1.6 years) demonstrated that LGE was associated with adverse events in children with HCM (log-rank;
P
=0.029).

Conclusions—

The prevalence and extent of LGE in children with HCM approximate to those in adults with HCM. Furthermore, children with HCM with LGE tend to have adverse events, and larger researches with longer follow-up are required.
Assessment of Mitral Valve Adaptation With Gated Cardiac Computed Tomography
Authors: Beaudoin Jonathan , Thai Wai-Ee , Wai Bryan , Handschumacher Mark D. , Levine Robert A. , Truong Quynh A.
Published: July 2013

Background—

Mitral valve (MV) enlargement is a compensatory mechanism capable of preventing functional mitral regurgitation (FMR) in dilated ventricles. Total leaflet area and its relation with closure area measured by 3-dimensional (3D) echocardiography have been related to FMR. Whether these parameters can be assessed with other imaging modalities is not known. Our objectives are to compare cardiac computed tomography (CT)–based measurements of MV leaflets with 3D echocardiography and determine the relationship of these metrics to the presence of FMR.

Methods and Results—

We used 2 cohorts of patients who had cardiac CT to measure MV total leaflet, closure, and annulus areas. In cohort 1 (26 patients), we validated these CT metrics to 3D echocardiography. In cohort 2 (66 patients), we assessed the relation of MV size with the presence of FMR in 3 populations: heart failure with FMR, heart failure without FMR, and normal controls. Cardiac CT and 3D echocardiography produced similar results for total leaflet (
R
2
=0.97), closure (
R
2
=0.89), and annulus areas (
R
2
=0.84). MV size was the largest in heart failure without FMR compared with controls and patients with FMR (9.1±1.7 versus 7.5±1.0 versus 8.1±0.9 cm
2
/m
2
;
P
<0.01). Patients with FMR had reduced ratios of total leaflet to closure areas and total leaflet to annulus areas when compared with patients without FMR (
P
<0.01).

Conclusions—

MV size measured by CT is comparable with 3D echocardiography. MV enlargement in cardiomyopathy suggests leaflet adaptation. Patients with FMR have inadequate adaptation as reflected by decreased ratios of leaflet area and areas determined by ventricle size (annulus and closure areas). These measurements provide additional insight into the mechanism of FMR.
Lessons From the Tc-99m Shortage
Authors: Small Gary R. , Ruddy Terrence D. , Simion Oana , Alam Mohammed , Fuller Lyanne , Chen Li , Beanlands Rob S. , Chow Benjamin J.W.
Published: July 2013

Background—

In 2009, the Chalk River nuclear reactor closed for repairs that led to a critical shortage of technetium-99m (Tc-99m). Several centers used thallium-201 (Tl-201) as an alternative radiotracer for myocardial perfusion imaging. Because Tl-201 is considered by many as a suboptimal radiotracer, we sought to understand the impact of using Tl-201 (during the Tc-99m shortage) on downstream resource utilization.

Methods and Results—

We performed a retrospective study at the Ottawa Heart Institute of 7402 patients (60% men; mean age, 62.6±11.8 years), patients were referred for myocardial perfusion imaging between May 2008 and January 2011 (PRE_Tc-99m [2938 patients]), during (DURING_Tl-201 [2959 patients]), and after (POST_Tc-99m [1505 patients]) the Tc-99m shortage. Patients were followed for 6 months after their index myocardial perfusion imaging to determine subsequent rates of cardiac catheterization or noninvasive imaging. More downstream testing was seen in the Tl-201 cohort (639 [21.4%] patients) than the Tc-99m cohort (537 [12.1%] patients;
P
<0.001). After adjustment using propensity scores, differences in downstream referral rates were maintained. The downstream investigations resulted in an estimated increase in per-patient costs ($165.22; 95% confidence interval, 153.00–177.42) in the DURING_Tl-201 cohort compared with the Tc-99m cohort ($90.97; 95% confidence interval, 83.42–98.90;
P
<0.001). As well, the mean effective radiation dose per-patient was higher in DURING_Tl-201 (23.57 mSv; 95% confidence interval, 23.16–23.96) than in Tc-99m (12.92 mSv; 95% confidence interval, 12.55–13.40;
P
<0.001).

Conclusions—

In this single-center study, the use of Tl-201 during the Tc-99m shortage was associated with an increase in downstream testing, cost, and patient radiation exposure, but these findings may not be generalizable to other centers. Although Tl-201 provided a short-term solution to the unexpected Tc-99m shortage, long-term cost-effective solutions should be areas of future study.
Expansion of Invasive Cardiac Services in the United States
Authors: Horwitz Jill R. , Nichols Austin , Nallamothu Brahmajee K. , Sasson Comilla , Iwashyna Theodore J.
Published: July 2013

Background—

The number of hospitals offering invasive cardiac services (diagnostic angiography, percutaneous coronary intervention, and coronary artery bypass grafting) has expanded, yet national patterns of service diffusion and their effect on geographic access to care are unknown.

Methods and Results—

This is a retrospective cohort study of all hospitals in fee-for-service Medicare, 1996 to 2008. Logistic regression identified the relationship between cardiac service adoption and the proportion of neighboring hospitals within 40 miles already offering the service. From 1996 to 2008, 397 hospitals began offering diagnostic angiography, 387 percutaneous coronary intervention, and 298 coronary artery bypass grafting (increasing the proportion with services by 3%, 11%, and 4%, respectively). This capacity increase led to little new geographic access to care; the population increase in geographic access to diagnostic angiography was 1 percentage point; percutaneous coronary intervention 5 percentage points, and coronary artery bypass grafting 4 percentage points. Controlling for hospital and market characteristics, a 10 percentage point increase in the proportion of nearby hospitals already offering the service increased the odds by 10% that a hospital would add diagnostic angiography (odds ratio, 1.102; 95% confidence interval, 1.018–1.193), increased the odds by 79% that it would add percutaneous coronary intervention (odds ratio, 1.794; 95% confidence interval, 1.288–2.498), and had no significant effect on adding coronary artery bypass grafting (odds ratio, 0.929; 95% confidence interval, 0.608–1.420).

Conclusions—

Hospitals are most likely to introduce new invasive cardiac services when neighboring hospitals already offer such services. Increases in the number of hospitals offering invasive cardiac services have not led to corresponding increases in geographic access.
Ca
2+
/Calmodulin-Dependent Protein Kinase II and Protein Kinase A Differentially Regulate Sarcoplasmic Reticulum Ca
2+
Leak in Human Cardiac Pathology
Authors: Fischer Thomas H. , Herting Jonas , Tirilomis Theodor , Renner André , Neef Stefan , Toischer Karl , Ellenberger David , Förster Anna , Schmitto Jan D. , Gummert Jan , Schöndube Friedrich A. , Hasenfuss Gerd , Maier Lars S. , Sossalla Samuel
Published: July 2013

Background—

Sarcoplasmic reticulum (SR) Ca
2+
leak through ryanodine receptor type 2 (RyR2) dysfunction is of major pathophysiological relevance in human heart failure (HF); however, mechanisms underlying progressive RyR2 dysregulation from cardiac hypertrophy to HF are still controversial.

Methods and Results—

We investigated healthy control myocardium (n=5) and myocardium from patients with compensated hypertrophy (n=25) and HF (n=32). In hypertrophy, Ca
2+
/calmodulin-dependent protein kinase II (CaMKII) and protein kinase A (PKA) both phosphorylated RyR2 at levels that were not different from healthy myocardium. Accordingly, inhibitors of these kinases reduced the SR Ca
2+
leak. In HF, however, the SR Ca
2+
leak was nearly doubled compared with hypertrophy, which led to reduced systolic Ca
2+
transients, a depletion of SR Ca
2+
storage and elevated diastolic Ca
2+
levels. This was accompanied by a significantly increased CaMKII-dependent phosphorylation of RyR2. In contrast, PKA-dependent RyR2 phosphorylation was not increased in HF and was independent of previous β-blocker treatment. In HF, CaMKII inhibition but not inhibition of PKA yielded a reduction of the SR Ca
2+
leak. Moreover, PKA inhibition further reduced SR Ca
2+
load and systolic Ca
2+
transients.

Conclusions—

In human hypertrophy, both CaMKII and PKA functionally regulate RyR2 and may induce SR Ca
2+
leak. In the transition from hypertrophy to HF, the diastolic Ca
2+
leak increases and disturbed Ca
2+
cycling occurs. This is associated with an increase in CaMKII- but not PKA-dependent RyR2 phosphorylation. CaMKII inhibition may thus reflect a promising therapeutic target for the treatment of arrhythmias and contractile dysfunction.
Intercultural Encounters in Collective Narratives: The Transition of “The Shining Robe” from North Africa to Ashkenaz via Provence
Authors: Kushelevsky Rella
Published: July 2013

Abstract

Collective narratives that have been received by a society as part of its culture are based on and respond to prevalent norms and values. Whether they conform to or criticize existing conventions, collective narratives are created within a cultural historical context that should be reconstructed as a point of departure for interpretation. In this article I focus on “The Shining Robe”, a story incorporated in Hibbur Yafeh MeHa’yeshua authored by Rabbi Nissim Gaon of Kairouan (first half of the 11th century). The choice of this story is intriguing due to its foreign nature and its departure from the gender norms that prevailed in Ashkenaz, compared to the gender norms that were prevalent in the Jewish-Muslim context. I argue that the response that this story evoked in Ashkenaz, whether explicit or implicit, made it necessary to cross cultural bridges between Kairouan where it was created and the cultural context where it was received. I refer to the Judeo-Arabic version of Hibbur Yafeh in comparison to its translations-adaptations in Ashkenaz dated to the 13th-16th centuries. These adapted versions are briefly compared also to its parallel in Provence, translated from the Judeo-Arabic.
Early Muslim Medicine and the Indian Context: A Reinterpretation
Authors: Shefer-Mossensohn M. , Hershkovitz K. Abou
Published: July 2013

Abstract

The past few decades have witnessed a remarkable shift in the way scholars study the field of sciences in Muslim societies. Up to the 1980s, research focused on Muslim scientists’ role as transmitters of science to the West, and as contributors to Western science. The Muslim world was commonly viewed as a link between ancient Greece and Latin Christendom, its scholars serving as translators of Greek treatises, and as preservers of Greek knowledge. Recently, the theme of Indian-Muslim cultural-scientific relations has attracted growing attention. Following this trend, we maintain that the eighth and ninth centuries reveal an interaction between Indian and Muslim medicine and physicians. Building on the past work of scholars such as Michael W. Dols and more recently Kevin van Bladel, we reinterpret medieval Arabic sources to reveal that the interest in Asian science was not a brief and untypical phenomenon that lacked long-lasting implications. By rereading Arabic chronicles and biographical dictionaries, we will portray how a rather brief contact between ʿAbbāsid Iraq and India proved to yield enduring influences. We will focus on two aspects of Muslim medical practice for demonstrating the Indian connection: the presence of Indian physicians in Baghdād in and around the ʿAbbāsid court, and the emergence of early Muslim hospitals.
Spectacle, Community and Holy War in Fourteenth-Century Cyprus
Authors: Devaney Thomas
Published: July 2013

Abstract

This article examines how temporal and ecclesiastic authorities on Lusignan Cyprus used rhetoric and performance to mobilize support for the Alexandria Crusade. While King Peter I appealed to the chivalric ideals of his vassals in order to overcome their reluctance to endanger the kingdom’s economic and military security, papal legate Peter of Thomas led interfaith processions that presented Cyprus’s population as united in its Christian devotion despite long-standing tensions between the Latin and Greek communities. This presentation of a shared Cypriot identity reflected nascent moves away from the physical and social segregation of confessional groups. It also clarifies the role played by perceptions of a constant threat of Mamlūk invasion in this process of acculturation. Such concerns and responses were not unique to Cyprus. By considering late-medieval Cyprus as a frontier society, we can gain insight into the complex politics of holy war in other composite medieval communities.
“Halting Between Two Opinions”: Conversion and Apostasy in Early Islam
Authors: Simonsohn Uriel
Published: July 2013

Abstract

The phenomenon of individuals converting to Islam and later returning to their former religions is well attested in both narrative and documentary records from the early Islamic period. Such shifts in religious commitments posed social and legal problems for the communities to which their former members sought reentry. Specifically, legal authorities were faced with the challenge of assessing the trustworthiness of returning apostates, whether their return was wholehearted and sincere or, rather, opportunistic and deceitful. The present discussion offers the historical context and a comparative analysis of some of the legal mechanisms by which the Jewish geʾonim of Babylonia and Eastern Christian church leaders attempted to overcome this challenge.
Longitudinal assessment of thyroid function in pregnancy
Authors: Ekinci Elif I , Lu Zhong X , Sikaris Ken , Bittar Intissar , Cheong Karey Y , Lam Que , Crinis Nick , Houlihan Christine A
Published: July 2013

Background

Trimester-specific reference intervals (RIs) for thyroid function tests are lacking for Beckman Dxl 800 analysers. We aimed to establish RIs for thyroid stimulating hormone (TSH), free thyroxine (fT4) and to track intraindividual changes in thyroid function throughout pregnancy.

Methods

One hundred and thirty healthy women without antithyroid peroxidase antibodies were followed longitudinally. Thyroid function was determined at trimester-1 (T1): 9–13 weeks; trimester-2 (T2): 22–26 weeks; trimester-3 (T3): 35–39 weeks and postpartum (PP): 8–12 weeks. A subgroup ( n = 47) was used to track intraindividual changes using PP as non-pregnant state (baseline).

Results

For trimesters 1–3, TSH (median (2.5th, 5th, 95th and 97.5th percentile)) was 0.77 (0.03, 0.05, 2.33, 3.05), 1.17 (0.42, 0.47, 2.71, 3.36) and 1.35 (0.34, 0.42, 2.65, 2.83) mIU/L, respectively. Free T4 (mean (95%CI)) was 10.7 (5.9–15.5), 8.1 (4.9–11.3), 7.8 (4.5–11.0) pmol/L, respectively. In T2 and T3, 36% and 41% of the fT4 values, respectively, fell below the non-pregnancy lower normal limit. In the subgroup assessed for longitudinal changes, of the women with baseline TSH ⩽ median, 71–75% remained at or below the corresponding median for trimesters 1–3. Of the women with baseline fT4 ⩽ median, 69–81% also remained at or below the corresponding median for trimesters 1–3. High correlation was observed at different trimesters and baseline for TSH (Spearman’s r: 0.593–0.846, P < 0.001) and for fT4 ( r: 0.480–0.739, P < 0.001).

Conclusions

Use of trimester-specific RIs would prevent misclassification of thyroid function during pregnancy. In the majority of women, TSH and fT4 tracked on the same side of the median distribution, from a non-pregnant baseline, throughout pregnancy.
A diagnostic conundrum: heterophilic antibody interference in an adrenocorticotropic hormone immunoassay not detectable using a proprietary heterophile blocking reagent
Authors: Grasko Jonathan , Willliams Robin , Beilin Jonathan , Glendenning Paul , Fermoyle Soraya , Vasikaran Samuel
Published: July 2013

Context

Heterophilic antibodies are a well-described interferent but poorly appreciated and are often not a recognized problem affecting most immunoassays. We describe for the first time heterophilic antibodies interference affecting an adrenocorticotropic hormone (ACTH) assay in a patient with Cushing’s syndrome due to bilateral nodular adrenal hyperplasia.

Case

A 60-year-old retired female nurse underwent extensive invasive investigations, which were ultimately unnecessary, as a result of initial analytical interference in the ACTH assay, which could not be resolved using a proprietary heterophilic binding reagent.

Results

This case highlights the inherent difficulty of diagnosing Cushing’s syndrome and the large emphasis placed on laboratory tests. The consequence of not initially identifying interference in this patient’s laboratory test results led to unnecessary and costly investigations with potentially adverse outcomes.

Conclusions

Clinicians and the laboratory community need to be continuously vigilant and view laboratory results with caution when they are inconsistent with the clinical picture. This approach is paramount, especially at a time of increasing automation and ever-diminishing scientist involvement in sample processing.
Levodopa therapy in Parkinson’s disease: influence on liquid chromatographic tandem mass spectrometric-based measurements of plasma and urinary normetanephrine, metanephrine and methoxytyramine
Authors: Eisenhofer Graeme , Brown Sebastian , Peitzsch Mirko , Pelzel Daniela , Lattke Peter , Glöckner Stephan , Stell Anthony , Prejbisz Aleksander , Fassnacht Martin , Beuschlein Felix , Januszewicz Andrzej , Siegert Gabriele , Reichmann Heinz
Published: July 2013

Background

Medication-related interferences with measurements of catecholamines and their metabolites represent important causes of false-positive results during diagnosis of phaeochromocytomas and paragangliomas (PPGLs). Such interferences are less troublesome with measurements by liquid chromatography with tandem mass-spectrometry (LC-MS/MS) than by other methods, but can still present problems for some drugs. Levodopa, the precursor for dopamine used in the treatment of Parkinson’s disease, represents one potentially interfering medication.

Methods

Plasma and urine samples, obtained from 20 Parkinsonian patients receiving levodopa, were analysed for concentrations of catecholamines and their O-methylated metabolites by LC-MS/MS. Results were compared with those from a group of 120 age-matched subjects and 18 patients with PPGLs.

Results

Plasma and urinary free and deconjugated (free + conjugated) methoxytyramine, as well as urinary dopamine, showed 22- to 148-fold higher ( P < 0.0001) concentrations in patients receiving levodopa than in the reference group. In contrast, plasma normetanephrine, urinary noradrenaline and urinary free and deconjugated normetanephrine concentrations were unaffected. Plasma free metanephrine, urinary adrenaline and urinary free and deconjugated metanephrine all showed higher ( P < 0.05) concentrations in Parkinsonian patients than the reference group, but this was only a problem for adrenaline. Similar to normetanephrine, plasma and urinary metanephrine remained below the 97.5 percentiles of the reference group in almost all Parkinsonian patients.

Conclusions

These data establish that although levodopa treatment confounds identification of PPGLs that produce dopamine, the therapy is not a problem for use of LC-MS/MS measurements of plasma and urinary normetanephrine and metanephrine to diagnose more commonly encountered PPGLs that produce noradrenaline or adrenaline.
Is Executive Function Intact After Pediatric Intracranial Hemorrhage? A Sample of Mexican Children With Hemophilia
Authors: Morales Guadalupe , Matute Esmeralda , Murray Joan , Hardy David J. , O’Callaghan Erin T. , Tlacuilo-Parra Alberto
Published: July 2013

The goal of this study was to examine executive functioning outcomes in children with hemophilia who have suffered intracranial hemorrhage. We assessed 10 boys with hemophilia with intracranial hemorrhage; 6 boys with hemophilia without intracranial hemorrhage; and 10 healthy boys as controls. Intellectual functioning was assessed with subscales from the Wechsler Intelligence Scale for Children–Mexican Revision. Concept formation and reasoning, cognitive flexibility, and planning and organization domains from a neuropsychological assessment battery for Spanish-speaking children were employed for our analysis. Results indicated that children with intracranial hemorrhage demonstrated significant impairment on some measures of executive function compared with the control groups. All differences reflected poorer performance by the intracranial hemorrhage group. These results may reflect the impact of disruption to immature brain circuits and the deficiency of functional specificity within the immature brain. This is the only known study examining neuropsychological functioning in Mexican youth with hemophilia.
Improving Safe Sleep Environments for Well Newborns in the Hospital Setting
Authors: Mason Brooke , Ahlers-Schmidt Carolyn R. , Schunn Christy
Published: July 2013

Objective. Following the “Back to Sleep” campaign, deaths from sudden infant death syndrome (SIDS) were reduced. However, SIDS and sleep-related deaths continue to occur. Studies demonstrate that modeling by health care workers influences parents to place infants supine for sleep. Recently, additional emphasis has been placed on environment. The purpose of this study was to improve sleep position and environment in the hospital. Methods. A Plan-Do-Study-Act cycle was initiated. Sleeping infants were observed at baseline. A bundled intervention was implemented; infants were again observed. Parents were surveyed. Results. At baseline, 25% (36/144) of sleeping infants were safe; the majority of unsafe sleep was a result of environment. Postintervention, significantly more (58%; 145/249) had safe sleep ( P < .0001). Most parents planned to use the supine position (95%; 96/101); none planned to cosleep. Many intended to adjust their infants’ home sleep environment. Conclusion. Using a multifaceted approach significantly improved infant safe sleep practice in the hospital setting.
Prevalence of Vitamin D Deficiency in International Adoptees Within the First 6 Months After Adoption
Authors: Gustafson Kimara L. , Eckerle Judith K. , Howard Cynthia R. , Andrews Beth , Polgreen Lynda E.
Published: July 2013

Background. Vitamin D deficiency impairs bone health and development. Objective. To determine the prevalence of and risk factors for vitamin D deficiency in pediatric international adoptees. Methods. A prospective cohort (N = 189) study from a single international adoption clinic was conducted. Total 25-hydroxy vitamin D [25(OH)D] level was measured at the initial clinical assessment (within 6 months of adoption). Vitamin D deficiency was defined as a 25(OH)D <20 ng/mL (<8 nmol/L) and insufficiency as 25(OH)D <30 ng/mL (<12 nmol/L). Results. Vitamin D deficiency was diagnosed in 8% and insufficiency in 27% of the cohort. Lower body mass index and longer time in an institution were associated with vitamin D deficiency and insufficiency independent of age. Conclusions. Vitamin D insufficiency was common in our cohort of international adoptees. The significance of vitamin D insufficiency on bone development during the typical “catch-up” growth following international adoption needs to be determined.
Anticipated Increases in Medically Attended Injuries by Children and Young Adults With the Affordable Care Act
Authors: Winston Flaura K. , Zonfrillo Mark R. , García-España J. Felipe , Miller Ted R.
Published: July 2013

Objectives. To guide implementation of the Affordable Care Act 2010 by estimating anticipated increases in medically attended injuries and site of care by the young who are currently uninsured. Methods. The 2008 National Health Interview Survey was used to estimate injury episodes and care site for uninsured and insured youth ≤26 years old. Increases in medically attended injuries were estimated by assuming that rates and care site for the currently uninsured would match those of the currently insured once the uninsured receive coverage. Results. In 2008, approximately 11 938 800 episodes of medically attended injuries occurred for youth ≤26 years. An anticipated 6.1% increase in medically attended injuries (737 081; 95% confidence interval = 564 000-879 000), the majority of which would be seen in the outpatient setting, could occur once all uninsured youth become insured. Conclusions. Injury prevention strategies and additional injury care training for primary care physicians may help ensure appropriate triage and optimal outcomes while containing costs.
Oil, Democracy, and Context
Authors: Ahmadov Anar K.
Published: July 2013

A considerable debate precludes drawing conclusions about oil’s effect on democracy. This article challenges this stalemate by significantly expanding the scope of the previous research and using meta-regression analysis to examine the integrated results of extant scholarship. While the results suggest a nontrivial negative association between oil and democracy across the globe, they also indicate a notable variation in this relationship across world regions and institutional contexts. A conditioning effect of institutions may lie more in a broader set of economic and political institutions, less so in previous political regime, but not in institutions associated with British colonial past. Finally, while oil does not seem to impede democracy by retarding two key channels of modernization—income and urbanization—it may have an indirect negative effect on democracy through its adverse impact on education.
Violence as Honorable? Racial and Ethnic Differences in Attitudes Toward Violence
Authors: Rose Mary R. , Ellison Christopher G.
Published: July 2013

Criminologists have suggested that Latinos differ from Southern Whites in their views of violence. A sample of 1,429 Texans indicated whether they agreed that violence deserves a violent response, whether violence is necessary to prevent future violence, and whether people have a right to kill in defense of self or family. Controlling for other factors, Latinos and African Americans were more likely than non-Hispanic Whites to disagree about the need for violence in preventing future harm and the right to self-defense. Less-acculturated Latinos, indicated by whether they took the survey in Spanish, were the least supportive of violence. Despite having roots in a so-called “culture of honor,” Latino immigrants, as well as those who are U.S. citizens, have distinct views on violence.
Sociocultural Boundary Formations in College Life and Intercultural Capital Development
Authors: Oikonomidoy Eleni
Published: July 2013

Based on selective findings from a qualitative study with first generation college students, this article presents the contradictory and complex ways in which the participants perceived sociocultural diversity on campus and their place within it. The students’ narratives both affirmed existing boundaries of social belonging based on the conventional categories of race, ethnicity, and social class and transcended them. Cross-border alliances were being built on campus at the same time that new boundaries were forming in unconscious ways. The discussion focuses on the implications of this study for intercultural capital development.
Developing Instructional Leaders Through Assistant Principals’ Academy
Authors: Gurley D. Keith , Anast-May Linda , Lee H. T.
Published: July 2013

This article describes findings from a single-case qualitative study of a unique 2-year professional development academy for practicing assistant principals designed and implemented in partnership between school district personnel and university educational leadership faculty members. The study was conducted based on the theoretical framework of instructional leadership developed by Murphy. Academy participants reported an increase in instructional leadership skills, the development of an institutional perspective, key collaborative and networking skills, and growth in confidence in their ability to conceptualize the role and to act as successful principals. District leaders indicated that program goals to develop a cadre of assistant principals who are ready to assume instructional and managerial leadership roles as principals had been met.
The Impact of Learning Time on Academic Achievement
Authors: Jez Su Jin , Wassmer Robert W.
Published: July 2013

As schools aim to raise student academic achievement levels and districts wrangle with decreased funding, it is essential to understand the relationship between learning time and academic achievement. Using regression analysis and a data set drawn from California’s elementary school sites, we find a statistically significant and positive relationship between the number of instructional minutes in an academic year and school-site standardized test scores. Fifteen more minutes of school a day at a school site (or about an additional week of classes over an academic year) relates to an increase in average overall academic achievement of about 1%, and about a 1.5% increase in average achievement for disadvantaged students. This same increase in learning time yields the much larger 37% gain in the average growth of socioeconomically disadvantage achievement from the previous academic year. Placing this impact in the context of other influences found important to academic achievement, similar increases in achievement only occur with an increase of fully credentialed teachers by nearly 7 percentage points. These findings offer guidance regarding the use of extended learning time to increase academic performance. Moreover, they suggest caution in reducing instructional time as the default approach to managing fiscal challenges.
Determinants of Graduation Rate of Public Alternative Schools
Authors: Izumi Masashi , Shen Jianping , Xia Jiangang
Published: July 2013

In this study we investigated determinants of the graduation rate of public alternative schools by analyzing the most recent, nationally representative data from Schools and Staffing Survey 2007-2008. Based on the literature, we built a series of three regression models via successive block entry, predicting the graduate rate first by (a) student demographics, then by (a) student demographics and (b) staffing characteristics, and finally by (a) student demographics, (b) staffing characteristics, and (c) school processes, with a purpose to compare the models to study the effects of those variables more amenable to policies (i.e., staffing characteristics and school processes). Among others, we found (a) that staffing characteristics and school processes are important blocks of variables to predict the graduation rate, (b) that summer programs and Hispanic teacher ratio are positively associated with the graduation rate, with having same teachers for 2 years or more being a marginally positive predictor, and (c) that having the traditional grade structure and providing day care are negatively correlated with the graduation rate. Implications of our findings for policy and future research are discussed.