bluuebunny/crossref_metadata_2025 huggingface dataset:
Multicenter, intra‐individual comparison of single dose gadobenate dimeglumine and double dose gadopentetate dimeglumine for MR angiography of the peripheral arteries (the Peripheral VALUE Study)
Authors: Wang Jian , Yan Fuhua , Liu Jianyu , Lu Jianping , Li Dan , Luan Jingyuan , Wang Xiaoying , Li Yuan , Iezzi Roberto , De Cobelli Francesco
Published: January 2013

Purpose

To prospectively compare single dose gadobenate dimeglumine with double dose gadopentetate dimeglumine for CE‐MRA in patients with peripheral arterial occlusive disease (PAOD) using an intra‐individual crossover study design in which all patients received both contrast agents in otherwise identical CE‐MRA examinations.

Materials and Methods

Institutional review board and regulatory approval were granted and all patients provided written informed consent. Sixty‐eight patients (53M/15F; 62.4 ± 15.7 years) with mild‐to‐severe PAOD were enrolled for randomized 3‐station CE‐MRA with 0.1 mmol/kg gadobenate dimeglumine and 0.2 mmol/kg gadopentetate dimeglumine. Three blinded readers assessed images for vessel anatomical delineation, disease detection/exclusion, and global preference. Diagnostic performance for detection of ≥51% stenosis was determined for 53 patients who underwent DSA. Noninferiority was assessed using the Wilcoxon Signed Rank, McNemar, and Wald tests. Quantitative enhancement was compared.

Results

No differences (P ≥ 0.25) were noted for any qualitative parameter at any station. Equivalence was reported in at least 62/64 patients (93.8% 3‐reader agreement) for diagnostic preference. Superiority for gadobenate dimeglumine was reported by all readers for diagnostic performance (sensitivity: 80.4–88.0% versus 75.2–85.8%; specificity: 89.8–96.0% versus 88.7–94.8%; accuracy: 87.4–91.7% versus 84.9–90.6%; PPV: 84.0–92.8% versus 82.3–90.8%; NPV: 88.5–92.4% versus 85.7–91.1%). Quantitative enhancement was similar in the pelvis but significantly (P < 0.05) greater with gadobenate dimeglumine in the thigh for two readers.

Conclusion

Image quality and diagnostic performance on peripheral CE‐MRA with 0.1 mmol/kg gadobenate dimeglumine is at least equivalent to that with 0.2 mmol/kg gadopentetate dimeglumine. J. Magn. Reson. Imaging 2013;38:926–937. © 2013 Wiley Periodicals, Inc.
Improvement of gadoxetate arterial phase capture with a high spatio‐temporal resolution multiphase three‐dimensional SPGR‐dixon sequence
Authors: Hope Thomas A. , Saranathan Manojkumar , Petkovska Iva , Hargreaves Brian A. , Herfkens Robert J. , Vasanawala Shreyas S.
Published: January 2013

Purpose

To determine whether a multiphase method with high spatiotemporal resolution (STR) by means of a combination of parallel imaging, pseudorandom sampling and temporal view sharing improves the capture and intensity of gadoxetate arterial phase images as well as lesion enhancement.

Materials and Methods

Thirty‐seven patients were imaged with a conventional spoiled gradient echo acquisition and 48 with a high STR multiphase acquisition after the administration of gadoxetate. Arterial phase capture, image quality, and quality of fat suppression were qualitatively graded. Fourteen lesions in the conventional group and 28 in the high STR multiphase group were imaged, including 34 focal nodular hyperplasias. The ratio of lesion to parenchyma enhancement as well as relative hepatic artery enhancement were calculated. Chi‐squared, Mann‐Whitney U and student t‐tests were used to compare differences.

Results

The high STR multiphase acquisition included the arterial phase more frequently than conventional acquisitions (P < 0.001), with the arterial phase missed in 17% (95% CI of 4–28%) of patients with conventional acquisition compared with 2% (95% CI of 0–6%) with the high STR multiphase acquisition. There was no loss of image quality or degree of fat saturation. Additionally, there was increased relative intensity of the hepatic arteries (P < 0.001) as well as lesion enhancement (P = 0.01).

Conclusion

The high STR multiphase acquisition resulted in more reliable gadoxetate arterial phase capture compared with a conventional acquisition while preserving image quality with robust fat saturation J. Magn. Reson. Imaging 2013;38:938–945. © 2013 Wiley Periodicals, Inc.
MR elastography of the human abdominal aorta: A preliminary study
Authors: Xu Lei , Chen Jun , Glaser Kevin J. , Yin Meng , Rossman Phillip J. , Ehman Richard L.
Published: January 2013

Purpose

To investigate the feasibility of using MR elastography (MRE) for the evaluation of the stiffness of in vivo aortic wall.

Materials and Methods

To validate the experimental approach for imaging the aorta in vivo, a gel phantom with an embedded porcine aorta was imaged in the presence of fluid flow within the aorta. The potential changes in the elasticity of the vessel wall with changes in pressure were investigated. The feasibility of performing MRE of abdominal aorta was assessed in five volunteers (age, 22–40 years; body mass index, 21.5–25.2 kg/m2). The pulse‐gated cine MRE technique was used to study the wave propagation along the aorta throughout the cardiac cycle and provide estimates of aortic stiffness in diastole.

Results

In the phantom study, the wave propagation was well visualized within the porcine aorta embedded in the gel phantom. An increase of the Young's modulus‐wall thickness (E*t) product with the increase in static pressure was observed. In the in vivo study, the waves were well visualized within the lumen of abdominal aorta in the five volunteers in diastolic phase, but they were not well visualized during systole.

Conclusion

MRE is feasible for noninvasively assessing the stiffness of the abdominal aorta and merits further investigation. J. Magn. Reson. Imaging 2013;38:1549–1553. © 2013 Wiley Periodicals, Inc.
Evaluation of etravirine resistance in clinical samples by a simple phenotypic Test
Authors: Agneskog Eva , Nowak Piotr , Källander Clas F.R. , Sönnerborg Anders
Published: January 2013

Drug resistance testing is an important tool in the management of HIV‐1 infection. As access to genotypic resistance assays is limited in low‐ and middle‐income settings, alternatives are warranted. The aim of the study was to adapt a phenotypic drug susceptibility assay, ExaVir Drug, for detection of resistance to the second generation non‐nucleoside reverse transcriptase inhibitor (NNRTI) etravirine (ETR). Five NNRTI resistant mutant forms of RT were produced (L100I, K103N, L100I/K103N, Y181C, V179D) in order to validate the assay for ETR. Furthermore, HIV‐1 RT was purified from plasma samples (n = 28) obtained from treatment naïve and experienced HIV‐1 infected patients, and ETR drug susceptibility (IC50) was estimated. The direct sequencing of thepolgene was performed. The recombinant RT mutants had the expected changes in drug sensitivity patterns. The RTs isolated from plasma of therapy naïve individuals showed low IC50for ETR. In the plasma virus from treatment experienced patients with Y181C, A98G, V108I, and/or K101E mutations in thepolgene, higher IC50values were found in line with reduced susceptibility data for ETR. This study demonstrates that ExaVir® Drug, a simple enzymatic phenotypic assay, can be used for detection of ETR resistance, including cross‐resistance to other NNRTIs, in clinical samples. A further evaluation is needed to define clinical cut‐offs; however the assay is an alternative to more costly HIV drug resistance tests, especially in low‐income countries. J. Med. Virol. 85:703–708, 2013. © 2013 Wiley Periodicals, Inc.
Rapid molecular diagnosis of measles virus infection in an epidemic setting
Authors: Michel Yanne , Saloum Kenda , Tournier Claire , Quinet Béatrice , Lassel Ludovic , Pérignon Alice , Grimprel Emmanuel , Carbajal Ricardo , Vabret Astrid , Freymuth François , Garbarg‐Chenon Antoine , Schnuriger Aurélie
Published: January 2013

During the 2011 measles outbreak in Paris (France), patients with clinical suspicion of measles were tested for virological confirmation of measles virus (MV) infection. To assess the practical value of molecular diagnosis in an epidemic setting, 171 oral fluid samples and 235 serum samples collected from 270 patients were tested prospectively for MV‐RNA using a novel one‐step real‐time RT‐PCR assay including an internal control. Serum samples were also tested for MV‐specific IgG and IgM antibodies. MV infection was confirmed by detection of MV‐RNA and/or MV‐IgM for 229 of the 270 patients. The results for the 102 cases with both serum and oral fluid samples available were used to compare the techniques. The detection rate of MV‐RNA by RT‐PCR was 98% (100/102) for oral fluid and 95% (97/102) for serum samples. The detection rate of MV‐IgM was 85% (87/102). Negative MV‐IgM results were observed mostly for serum samples collected early after the onset of the rash. A MV‐RNA standard of known concentration obtained by in vitro transcription was used to quantify MV‐RNA in samples. MV‐RNA copy numbers were significantly higher in oral fluid than in serum samples, but did not correlate with time of sampling (within 1 week after the onset of the rash), patient age, or vaccination status. During the early stage of infection, the MV‐RNA viral load in serum was lower in patients positive than in those negative for MV‐IgG. In conclusion, the one‐step real‐time RT‐PCR assay is a simple and sensitive tool suitable for MV diagnosis within hours. J. Med. Virol. 85:723–730, 2013. © 2013 Wiley Periodicals, Inc.
Prevalence and associated clinical characteristics of hepatitis B, C, and HIV infections among injecting drug users in Korea
Authors: Min Jung‐Ah , Yoon Yeongsil , Lee Hyeok Jin , Choi Jihye , Kwon Min , Kim Kisang , Lee Chang‐Uk , Kim Dai‐Jin , Yun Haesun
Published: January 2013

Injecting drug use is associated with an increased risk of blood‐borne viral infections, such as hepatitis B and C viruses (HBV and HCV, respectively) and human immunodeficiency virus (HIV). However, their prevalence, virological characteristics, and associated factors are not clear among the injecting drug users in Korea. The aim of this study was to determine the prevalence of HBV, HCV, and HIV infection, as well as their virological and clinical characteristics of injecting drug users in South Korea. Between 2007 and 2010, 318 injecting drug users (89.3% male; mean ± age 41.9 ± 8.15 years) were participated. While HIV infection was not found, the seroprevalence of anti‐HCV and HBV surface antigen (HBsAg) was 48.4% (n = 154) and 6.6% (n = 21), respectively. HBV/HCV co‐infection was found in 4.1% (n = 13). Occult HBV infection was suggested in 5.0% (n = 16). Among the HCV genotypes, 1b (37.7%) and 2a/2c (35.7%) were mostly often detected. HCV RNA was detected in 98.1% (n = 151/154) and high‐level viremia (HCV RNA level, ≥400,000 IU/ml) were observed in 59.6% (n = 90/151). In multiple logistic regression analysis, old age (OR 1.18 per year, 95% CI = 1.09–1.27) and ever‐sharing injecting equipment (OR 4.17, 95% CI = 1.39–12.45) independently predicted HCV mono‐infection. The prevalence of HBV and HCV infection were high but largely undiagnosed in the present sample of Korean injecting drug users. Strategic prevention, screening, and treatment are needed to reduce further transmission and morbidity. J. Med. Virol. 85:575–582, 2013. © 2013 Wiley Periodicals, Inc.
Latent viral infections in young patients with inflammatory diseases treated with biological agents: Prevalence of JC virus genotype 2
Authors: Comar Manola , Delbue Serena , Lepore Loredana , Martelossi Stefano , Radillo Oriano , Ronfani Luca , D'Agaro Pierlanfranco , Ferrante Pasquale
Published: January 2013

Treatment with biological drugs is associated with increased susceptibility to viral infections. Reactivation of JC virus (JCV) and human cytomegalovirus (HCMV) in adults after therapy has been documented. The long‐term effects of biological and conventional therapy on human herpesviruses and polyomaviruses infections in young patients were assessed. One hundred eighty‐six samples [urine, serum, and blood cells (PBMCs)] from 62 patients (15.8 ± 6.2 years old) with Crohn's disease, ulcerative rectocolitis or juvenile rheumatoid arthritis treated with immunotherapy or conventional therapy for over 12 months were tested by real time PCR. One hundred twenty‐four samples (urine and blood) from 62 matched healthy volunteers (13.8 ± 8.6 years old) were included as controls. Sequencing of the JCV viral protein 1 (VP1) and transcriptional control region (TCR) was performed. Herpes simplex virus 1/2 and varicella zoster virus genomes were not detected in any patients, whereas Epstein–Barr virus, HCMV, and human herpesvirus‐6 genomes were detected in 4.8%, 3.2%, and 1.6% of the patients, respectively. JCV was detected in 22.6% (14/62) of urine samples from patients and in 8% (5/62) from controls, in 50% (7/14) of sera from patients shedding JCV, and in 71.4% (5/7) of matched PBMCs. There was a significant association between infliximab treatment and excretion of JCV genotype 2. Subclinical infection/reactivation of JCV genotype 2 in young patients during infliximab therapy was demonstrated. Conversely, increased susceptibility to herpesviruses infection was not shown. Future studies are warranted to investigate the effects of JCV reactivation on the health of young patients treated with infliximab. J. Med. Virol. 85:716–722, 2013. © 2013 Wiley Periodicals, Inc.
Children's Memories of Removal: A Test of Attachment Theory
Authors: Melinder Annika , Baugerud Gunn Astrid , Ovenstad Kristianne Stigsdatter , Goodman Gail S.
Published: January 2013

We report a study of parents’ attachment orientations and children's autobiographical memory for an experience that according to Bowlby's (1982) attachment theory should be particularly threatening—children's forced separation from their parents. It was hypothesized that individual differences in parents’ attachment orientations would be associated with children's distress and memory for this highly traumatic event. Children (n = 28) were observed during forced removal from home or school by Child Protective Services due to allegations of child maltreatment. Children's memory for the removal was tested 1 week later, and biological parents (n = 28) completed an adult attachment measure. Parental attachment anxiety significantly predicted children's distress during less stressful phases of the removal, R2 = .25, and parents’ attachment‐related avoidance predicted fewer correct memory reports from the children (i.e., fewer hits to open‐ended questions, R2 = .16, and fewer hits to direct questions, R2 = .27). The findings indicate that attachment theory provides important guidance for understanding children's autobiographical memory for traumatic events.
The Impact of Posttraumatic Stress Disorder on Blood Pressure and Heart Rate in a Veteran Population
Authors: Paulus Eric J. , Argo Tami R. , Egge Jason A.
Published: January 2013

Hyperarousal is a hallmark of posttraumatic stress disorder (PTSD). PTSD has been associated with increased blood pressure (BP) and heart rate (HR) in veteran populations. We retrospectively identified male patients consulted to outpatient psychiatry at the Iowa City Veterans Affairs Healthcare System. Patients were divided into PTSD (n = 88) and non‐PTSD (n = 98) groups. All PTSD patients and a subset of non‐PTSD patients had documented blast exposure during service. The study investigated whether patients with PTSD had higher systolic blood pressure (SBP), diastolic blood pressure (DBP), and heart rate (HR) than patients without PTSD. The effect of trauma exposure on BP was also examined. Mean SBP (133.8 vs. 122.3 mm Hg; p < .001), DBP (87.6 vs. 78.6 mm Hg; p < .001), and HR (78.9 vs. 73.1 bpm; p < .001) were all significantly higher in the PTSD group. Trauma‐exposed patients without PTSD had significantly higher BP than nonexposed patients. The prevalence of hypertension (HTN) was 34.1% (diagnosed and undiagnosed) among PTSD patients. Patients with PTSD had higher BP and HR compared to patients without PTSD. Trauma exposure may increase BP in this population. These findings will increase awareness about the cardiovascular implications of PTSD.
Recent progress in tissue optical clearing
Authors: Zhu Dan , Larin Kirill V. , Luo Qingming , Tuchin Valery V.
Published: January 2013

Tissue optical clearing technique provides a prospective solution for the application of advanced optical methods in life sciences. This paper gives a review of recent developments in tissue optical clearing techniques. The physical, molecular and physiological mechanisms of tissue optical clearing are overviewed and discussed. Various methods for enhancing penetration of optical‐clearing agents into tissue, such as physical methods, chemical‐penetration enhancers and combination of physical and chemical methods are introduced. Combining the tissue optical clearing technique with advanced microscopy image or labeling technique, applications for 3D microstructure of whole tissues such as brain and central nervous system with unprecedented resolution are demonstrated. Moreover, the difference in diffusion and/or clearing ability of selected agents in healthy versus pathological tissues can provide a highly sensitive indicator of the tissue health/pathology condition. Finally, recent advances in optical clearing of soft or hard tissue for in vivo imaging and phototherapy are introduced.
Quantum junction plasmons in graphene dimers
Authors: Thongrattanasiri Sukosin , Manjavacas Alejandro , Nordlander Peter , de Abajo F. Javier García
Published: January 2013

The interaction between doped graphene nanoislands connected by narrow junctions constitutes an ideal testbed to probe quantum effects in plasmonic systems. Here, the interaction between graphene plasmons in neighboring nanoislands is predicted to be extremely sensitive to the size and shape of the junctions. The reported ab initio calculations reveal three different regimes of interaction: (1) for narrow bridges (<4 carbon‐atom rows), the conductance of the junction is too low to allow electron transport and the optical response is dominated by a characteristic bonding dipolar dimer mode that also appears in a classical description; (2) for wider junctions (4‐8 carbon rows), a strong charge polarization is induced across the junction, which gives rise to a novel junction plasmon that has no counterpart in a classical description; (3) for even wider junctions (≥8 rows), their conductance is sufficiently large to allow charge transport between the two graphene islands, resulting in a pronounced charge‐transfer plasmon, which can also be described classically. This work opens a new path for the investigation of intrinsic plasmon quantum effects.
Selective Fluorescence Quenching in Cationic Fluorene‐Thiophene Diblock Copolymers for Ratiometric Sensing of Anions
Authors: Fonseca Sofia M. , Galvão Rita P. , Burrows Hugh D. , Gutacker Andrea , Scherf Ullrich , Bazan Guillermo C.
Published: January 2013

The cationic, all‐conjugated AB diblock copolymer poly[9,9‐bis(2‐ethylhexyl)fluorene]‐b‐poly[3‐(6‐trimethylammoniumhexyl) thiophene] bromide (PF2/6‐b‐P3TMAHT) shows dual fluorescence from the poly(fluorene) (PF) and poly(thiophene) (PT) blocks. A comparison of fluorescence quenching of the cationic PT block fluorescence with unquenched PF block provides a sensitive ratiometric method for anion sensing. The application to analysis of halide ions, single‐ and double‐stranded DNA is demonstrated. High selectivity is observed with halide ions, with the strongest quenching being seen with iodide. The quenching with DNA can be used for nucleic acid quantification at sub‐μM concentrations.

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Controlling the Pore Sizes and Related Properties of Inverse Opal Scaffolds for Tissue Engineering Applications
Authors: Zhang Yu Shrike , Regan Kevin P. , Xia Younan
Published: January 2013

Inverse opal scaffolds are finding widespread use in tissue engineering and regenerative medicine. Herein, the way in which the pore sizes and related physical properties of poly(D,L‐lactide‐co‐glycolide) inverse opal scaffolds are affected by the fabrication conditions is systematically investigated. It is found that the window size of an inverse opal scaffold is mainly determined by the annealing temperature rather than the duration of time, and the surface pore size is largely determined by the concentration of the infiltration solution. Although scaffolds with larger pore or window sizes facilitate faster migration of cells, they show slightly lower compressive moduli than scaffolds with smaller pore or window sizes.
Existence and asymptotic behavior of solutions for quasilinear parabolic systems
Authors: Tian Canrong
Published: January 2013

This paper is concerned with the existence, uniqueness, and asymptotic behavior of solutions for the quasilinear parabolic systems with mixed quasimonotone reaction functions, the elliptic operators in which are allowed to be degenerate. By the method of the coupled upper and lower solutions, and its monotone iterations, it shows that a pair of coupled upper and lower solutions ensures that the unique positive solution exists and globally stable if the quasisolutions are equal. Moreover, we study the asymptotic behavior of solutions to the Lotka–Volterra model with the density‐dependent diffusion. Copyright © 2013 John Wiley & Sons, Ltd.
Stochastic functional differential equations with infinite delay driven by G‐Brownian motion
Authors: Ren Yong , Bi Qiang , Sakthivel R.
Published: January 2013

In this paper, we consider a class of stochastic functional differential equations with infinite delay at phase space BC ( − ∞ ,0]; Rd) driven by G‐Brownian motion (SFDEGs) in the framework of sublinear expectation spaces . We prove the existence and uniqueness of the solutions to SFDEGs with the coefficients satisfying the linear growth condition and the classical Lipschitz condition. In addition, we establish the exponential estimate of the solution. Copyright © 2013 John Wiley & Sons, Ltd.
The k‐ary Montgomery modular inverse over nonbinary computers
Authors: Chen Chien‐Yuan , Huang Chien‐Feng , Lin Yu‐Feng
Published: January 2013

This paper presents a k‐ary Montgomery modular inverse algorithm over nonbinary computers by using Sedjelmaci's right shift k‐ary greatest common divisor scheme. Over traditional binary computers, Kaliski's scheme can output Montgomery modular inverse Q − 12n mod P, where P is coprime to Q and n is the bit length of P. Over k‐ary computers, our algorithm can discover the k‐ary Montgomery inverse Q − 1km mod P, where P, Q, and k are pairwise relatively prime positive integers and m = log kP. In the worst case, the computational cost of our algorithm is O(m2)k‐ary digit operations. Copyright © 2013 John Wiley & Sons, Ltd.
Characterization of sodium dodecylsulphate and dodecylphosphocholine mixed micelles through NMR and dynamic light scattering
Authors: Manzo Giorgia , Carboni Maura , Rinaldi Andrea C. , Casu Mariano , Scorciapino Mariano A.
Published: January 2013

The complexity of biological membranes leads to the use of extremely simplified models in biophysical investigations of membrane‐bound proteins and peptides. Liposomes are probably the most widely used membrane models due, especially, to their versatility in terms of electric charge and size. However, liquid‐state NMR suffers the lack of such a model, because even the smallest liposomes slowly tumble in solution, resulting in a dramatic signals broadening. Micelles are typically used as good substitutes, with sodium dodecylsulphate (SDS) and dodecylphosphocholine (DPC) being the most widely employed surfactants. However, they are always used separately to mimic prokaryotic and eukaryotic membranes, respectively, and accurate investigations as a function of surface charge cannot be performed. In this work, the critical micelle concentration (CMC) of binary mixtures with different SDS/DPC ratios has been determined by following the chemical shift variation of selected1H and31P NMR signals as a function of total surfactant concentration. The regular solution theory and the Motomura's formalism have been applied to characterize the micellization both in water and in phosphate buffer saline, and results were compared with those obtained directly from the experimental NMR chemical shift. The ζ‐potential and size distribution of the mixed micelles have been estimated with dynamic light scattering measurements. Results showed that SDS and DPC are synergic and can be used together to prepare mixed micelles with different negative/zwitterionic surfactants molar ratio. Copyright © 2013 John Wiley & Sons, Ltd.
Ethambutol toxicity exacerbating the phenotype of CMT2A2
Authors: Fonkem Ekokobe , Skordilis Monica A. , Binkley Elaine M. , Raymer David S. , Epstein Avrom , Arnold W. David , Kissel John T. , Lawson Victoria H.
Published: January 2013

Introduction: CMT2A2 is associated with mutations in the mitofusin 2 gene, which encodes a protein involved in mitochondrial fusion. Ethambutol is an antimycobacterial agent associated with toxic optic neuropathies. Ethambutol‐induced optic neuropathy occurs in patients with mutations in a related fusion gene, OPA1, which is responsible for autosomal dominant optic atrophy. Methods: We describe a patient with CMT2A2 (MFN2 mutation: T669G, F223L) who developed accelerated weakness, vocal cord paralysis, and optic atrophy after receiving ethambutol. Results: Deterioration began within months of initiating ethambutol therapy. After discontinuation of ethambutol, neurologic deterioration stabilized with subsequent improvement in visual fields. Conclusions: CMT2A2 is part of a group of genetic disorders which share an association with the process of mitochondrial fusion. This case shows that patients with CMT2A2, and possibly other mitochondrial fusion defects, may be uniquely susceptible to ethambutol‐induced neurotoxicity. This has implications regarding the underlying pathophysiology of mitochondrial fusion defects. Muscle Nerve, 2013
Single‐fiber electromyography in amyotrophic lateral sclerosis and cervical spondylosis
Authors: Liu Mingsheng , Cui Liying , Guan Yuzhou , Li Benhong , Du Hua
Published: January 2013

Introduction

Cervical spondylosis (CS) is a common disease in adults and may coexist with amyotrophic lateral sclerosis (ALS). It is important to detect ALS coexisting with CS (ALS‐cs) at an early stage, especially when surgical treatment of CS is planned.

Methods

Single‐fiber electromyography was performed in 26 patients with ALS, 19 with ALS‐cs, and 22 with CS.

Results

Mean jitter, percentage of jitter >55 μs, and percentage of impulse blocking were not statistically different between ALS and ALS‐cs cases, but they were significantly lower in CS. Mean fiber density was not statistically different among the 3 groups. The percentage of pairs with jitter >55 μs exceeding 40% and mean jitter exceeding 55 μs had high sensitivity and specificity in the diagnosis of ALS.

Conclusions

Single‐fiber electromyography can supply valuable information in helping to differentiate ALS from CS. Muscle Nerve, 2013
Triple a syndrome in Japan
Authors: Ikeda Masanori , Hirano Makito , Shinoda Keiich , Katsumata Noriyuki , Furutama Daisuke , Nakamura Katsuya , Ikeda Shu‐Ichi , Tanaka Toshifumi , Hanafusa Toshiaki , Kitajima Hiroyuki , Kohno Hitoshi , Nakagawa Mizuho , Nakamura Yusaku , Ueno Satoshi
Published: January 2013

Introduction

Triple A syndrome is an autosomal recessive disease, characterized by esophageal achalasia, alacrima, and adrenal insufficiency, as well as involvement of the central, peripheral, and autonomic nervous systems. This disease mimics amyotrophic lateral sclerosis in some patients. The causative gene encodes ALADIN, a nuclear pore complex (NPC) component. Only 5 patients have been reported in Japan.

Methods

We conducted the first nationwide survey of triple A syndrome. Identified mutants were expressed as GFP‐fusion proteins in cultured cells.

Results

Two new patients were identified, and 1 had a novel mutation (p.Ser182fsX19). All mutant proteins tested were mislocalized from NPC to cytoplasm.

Conclusions

The most consistent neurological manifestation of triple A syndrome in Japanese patients was progressive bulbospinal muscular atrophy with both upper and lower motor neuron involvement, which mimicked motor neuron disease, similar to that seen in patients in Western countries. The identification of the new patients suggests that more cases are undiagnosed in Japan. Muscle Nerve 48: 381–386, 2013
Heterogeneity of quadriceps muscle phenotype in chronic obstructive pulmonary disease (Copd); implications for stratified medicine?
Authors: Natanek Samantha A. , Gosker Harry R. , Slot Ilse G.M. , Marsh Gemma S. , Hopkinson Nicholas S. , Man William D.‐C. , Tal‐Singer Ruth , Moxham John , Kemp Paul R. , Schols Annemie M.W.J. , Polkey Michael I.
Published: January 2013

Introduction

Quadriceps muscle dysfunction is common in COPD. Determining, and, if possible, predicting quadriceps phenotype in COPD is important for patient stratification for therapeutic trials.

Methods

In biopsies from 114 COPD patients and 30 controls, we measured fiber size and proportion and assessed the relationship with quadriceps function (strength and endurance), clinical phenotype (lung function, physical activity, fat‐free mass) and exercise performance. In a subset (n = 40) we measured muscle mid‐thigh cross‐sectional area by computed tomography.

Results

Normal ranges for fiber proportions and fiber cross‐sectional area were defined from controls; we found isolated fiber shift in 31% of patients, isolated fiber (predominantly type II) atrophy in 20%, both shift and atrophy in 25%, and normal fiber parameters in 24%. Clinical parameters related poorly to muscle biopsy appearances.

Conclusions

Quadriceps morphology is heterogeneous in COPD and cannot be predicted without biopsy, underlining the need for biomarkers. Muscle Nerve 48: 488–497, 2013
Muscle architecture adaptations to knee extensor eccentric training: Rectus femoris vs. vastus lateralis
Authors: Baroni Bruno Manfredini , Geremia Jeam Marcel , Rodrigues Rodrigo , De Azevedo Franke Rodrigo , Karamanidis Kiros , Vaz Marco Aurélio
Published: January 2013

Introduction: Changes in muscle architecture induced by eccentric knee extensor training remain unclear, as well the adaptive responses of synergistic knee extensor muscles with different geometrical designs. Methods: Ultrasonography images were taken from rectus femoris (RF) and vastus lateralis (VL) of 20 male volunteers before and after a non‐training control period of 4 weeks, and additional evaluations were performed after 4, 8, and 12 weeks of isokinetic eccentric training. Results: RF and VL had significant changes in muscle architecture within the first 4 training weeks, and the adaptive response throughout the intervention was similar. Muscle thickness increased by around 7–10%, fascicle length increased 17–19%, and pennation angle was unchanged. Conclusions: Increased muscle thickness due to eccentric training was related to increased fascicle length and not to pennation angle changes. Although RF and VL have a different fascicular geometry, they had similar morphological adaptations to eccentric training. Muscle Nerve 48: 498–506, 2013
Motor unit potential change with contraction level: A concentric macro electromyography study
Authors: Jabre Joe F. , Guan Yuzhou , Chui Kenneth K.H.
Published: January 2013

Introduction: Motor unit action potential (MUAP) reference values are usually given per muscle and age group. Our aim was to evaluate the change in MUAP size at different contraction levels using the concentric macro (ConMac) EMG technique. Methods: ConMac needles were used to record the electrode cannula MUAP and measure its amplitude and area during weak, moderate, and strong muscle contractions. Results: MUAP area and amplitude gradually increased from weak to strong contraction levels in all muscles studied. MUAP amplitudes were larger in distal than in proximal muscles, likely because of a higher fiber density distally. Conclusions: MUAP normal values in the literature per muscle do not take into account the contraction level at which they were recorded and can misrepresent the interpretation of normal. Concentric macro EMG is a simple and useful complement to routine EMG studies and yields additional information on MUAP neurophysiology. Muscle Nerve 48: 551–556, 2013
Assessment of transverse ultrasonographic parameters to optimize carpal tunnel syndrome diagnosis in a case–control study
Authors: Korstanje Jan‐Wiebe H. , Van Balen Richard , Scheltens‐De Boer Marjan , Blok Joleen H. , Slijper Harm P. , Stam Henk J. , Hovius Steven E.R. , Selles Ruud W.
Published: January 2013

Introduction: Transverse ultrasound measurements of the median nerve (MN) for diagnosis of carpal tunnel syndrome (CTS) suffer from inconsistent findings within and between patients and healthy subjects. The objective of this study was to improve ultrasound assessment of CTS.Methods: In a case–control study (51 patients, 25 controls) we evaluated the performance gained by: (1) correcting for ultrasound probe angulation; (2) including active parameters such as forceful gripping of the hand; and (3) including hand flexor tendon parameters.Results: Correcting ultrasound probe angulation increased the correct classification rate by 4.5%; including forceful gripping resulted in increasing it by 2.8%; and including the hand flexor tendon resulted in an increase of 1.3%.Conclusions: The best predictive model combines correcting probe angulation with forceful gripping parameters and hand flexor tendon parameters. However, the clinically most practical model might use only probe angulation correction.Muscle Nerve48: 532–538, 2013
Influence of maximum range of motion and stiffness on the viscoelastic stretch response
Authors: Sobolewski Eric J. , Ryan Eric D. , Thompson Brennan J.
Published: January 2013

Introduction

We examined the influence of maximum range of motion (MROM) and passive stiffness on the viscoelastic stretch response.

Methods

Four 30‐s constant‐angle passive stretches of the plantar flexors at a predetermined torque were performed to determine the rate and relative change in stress relaxation (decline in torque during each 30‐s stretch) and creep (increase in ankle joint angle across all 4 stretches). Stress relaxation and creep responses were examined between participants after they were ranked into high and low groups based on MROM and passive stiffness values.

Results

Stress relaxation responses were unaffected by MROM and passive stiffness; however, creep was influenced by differences in passive stiffness but not MROM.

Conclusions

Passive stiffness but not MROM influences the acute viscoelastic response to passive stretching. Participants with less stiff plantar flexors experience greater increases in range of motion when they are stretched at a constant torque. Muscle Nerve 48: 571–577, 2013
Screening for HIV‐associated peripheral neuropathy in resource‐limited settings
Authors: Cettomai Deanna , Kwasa Judith K. , Birbeck Gretchen L. , Price Richard W. , Cohen Craig R. , Bukusi Elizabeth A. , Kendi Caroline , Meyer Ana‐Claire L.
Published: January 2013

Introduction

Peripheral neuropathy is the most common neurological complication of human immunodeficiency virus (HIV) infection but is widely under‐diagnosed in resource‐limited settings. We investigated the utility of screening tools administered by nonphysician healthcare workers (HCW) and quantitative sensory testing (QST) administered by trained individuals for identification of moderate/severe neuropathy.

Methods

We enrolled 240 HIV‐infected outpatients using 2‐stage cluster randomized sampling. HCWs administered the several screening tools. Trained study staff performed QST. Tools were validated against a clinical diagnosis of neuropathy.

Results

Participants were 65% women, mean age 36.4 years, median CD4 324 cells/μL. A total of 65% were taking antiretrovirals, and 18% had moderate/severe neuropathy. The screening tests were 76% sensitive in diagnosing moderate/severe neuropathy with negative predictive values of 84–92%. QST was less sensitive but more specific.

Conclusions

Screening tests administered by HCW have excellent negative predictive values and are promising tools for scale‐up in resource‐limited settings. QST shows promise for research use. Muscle Nerve 48: 516–524, 2013
Early changes of muscle insulin‐like growth factor‐1 and myostatin gene expression in gastric cancer patients
Authors: Bonetto Andrea , Penna Fabio , Aversa Zaira , Mercantini Paolo , Baccino Francesco M. , Costelli Paola , Ziparo Vincenzo , Lucia Simone , Fanelli Filippo Rossi , Muscaritoli Maurizio
Published: January 2013

Introduction

Cachexia increases morbidity and mortality of cancer patients. The progressive loss of muscle mass negatively affects physical function and quality of life. We previously showed reduced muscle insulin‐like growth factor‐1 (IGF‐1) expression and enhanced myostatin signaling in tumor‐bearing animals. This study was aimed at investigating whether similar perturbations occur in gastric cancer patients.

Methods

Early perturbations of myostatin and IGF‐1 signaling (including the expression of muscle‐specific ubiquitin ligases) were investigated in 16 gastric cancer patients and in 6 controls by analyzing muscle mRNA expression with semiquantitative reverse transcriptase polymerase chain reaction (PCR) and real‐time PCR.

Results

In gastric cancer patients, muscle mRNA levels for IGF‐1, myostatin, and atrogin‐1 were reduced irrespective of weight loss (≤5% or >5%), whereas MuRF1 expression was unchanged.

Conclusions

IGF‐1 and myostatin mRNA levels are downregulated in gastric cancer patients who have minimal or no weight loss. These early alterations are particularly relevant in order to devise preventive and therapeutic strategies for cancer cachexia. Muscle Nerve 48: 387–392, 2013
Muscle coactivation: A generalized or localized motor control strategy?
Authors: Frey‐Law Laura A. , Avin Keith G.
Published: January 2013

Introduction: We examined generalized versus joint‐specific influences on muscle coactivation. Methods: Muscle coactivation was assessed during maximal isometric and isokinetic knee and elbow joint extension moments in 48 healthy subjects (27 men). Local (joint‐specific) and generalized (person‐specific) contributions were examined using a combination of statistical tests, including regression with generalized estimating equations (GEEs), exploratory factor analysis, and cluster analysis. Results: GEEs produced similar significant coefficients for gender and joint; contraction type and test condition (angle or velocity) were not significant. Factor analysis indicated 2 joint‐based factors, and cluster analysis indicated 2 groups of individuals, those with and without elevated coactivation at the knee and elbow. Women exhibited greater coactivation at both joints, but no consistent influences of angle or velocity were observed at either joint. Conclusion Muscle coactivation is a neuromuscular control response determined by local, joint‐specific, and generalized, individual‐specific influences. Muscle Nerve 48: 578–585, 2013
MRI of carriers of the apolipoprotein E e4 allele–evidence for structural differences in normal‐appearing brain tissue in e4+ relative to e4– young adults
Authors: Dowell Nicholas G. , Ruest Torsten , Evans Simon L. , King Sarah L. , Tabet Naji , Tofts Paul S. , Rusted Jennifer M.
Published: January 2013

Apolipoprotein E is a protein involved in cholesterol and lipid transport. The gene coding for this protein has three different alleles: e2, e3 and e4. The e4 allele is recognised as a significant risk factor for the development of Alzheimer's disease in later life. Paradoxically, behavioural and functional evidence has demonstrated that the e4 allele may confer a cognitive advantage to the carrier in youth. In this article, a range of sophisticated and novel structural imaging techniques were used to identify subtle differences in the brain tissue of groups of young e4 and homozygous e3 carriers that might support this paradox. Using voxel‐based morphometry of high‐resolution structural MR images, we identified a higher white matter volume ratio in e4 relative to homozygous e3 carriers. Furthermore, diffusion tensor imaging and tract‐based spatial statistics studies identified increases in axial diffusivity and mode of anisotropy in carriers of the e4 allele. In addition, quantitative magnetisation transfer data were analysed using tract‐based spatial statistics. Evidence of a trend towards an increased transverse relaxation time of the bound proton pool was detected in e4 carriers, indicative of altered white matter composition. These changes were found to correlate with indices of cognitive performance across the two groups, supporting the notion that such subtle differences in white matter integrity may confer neural advantages that contribute to cognitive outcomes and, potentially, to performance differences, such as observed here in a test of verbal fluency and reported previously by other researchers. Copyright © 2013 John Wiley & Sons, Ltd.
An algebraic multigrid approach to solve extended finite element method based fracture problems
Authors: Gerstenberger Axel , Tuminaro Raymond S.
Published: January 2013

This article proposes an algebraic multigrid (AMG) approach to solve linear systems arising from applications where strong discontinuities are modeled by the extended finite element method. The application of AMG methods promises optimal scalability for solving large linear systems. However, the straightforward (or ‘black‐box’) use of existing AMG techniques for extended finite element method problems is often problematic. In this paper, we highlight the reasons for this behavior and propose a relatively simple adaptation that allows one to leverage existing AMG software mostly unchanged. Numerical tests demonstrate that optimal iterative convergence rates can be attained that are comparable with AMG convergence rates associated with linear systems for standard finite element approximations without discontinuities. Published 2012. This article is a US Government work and is in the public domain in the USA.
Fully aromatic macrocycle‐terminated polyimide: synthesis and cross‐linking
Authors: Zhang Limei , Mu Jianxin , Jiang Zhenhua , Zhang Haibo , Yue Xigui
Published: January 2013

This study reported a method to prepare fully aromatic macrocycle‐terminated polyimides (MC‐PI). The macrocycle of aryl ether ketones was prepared from (4‐amino)phenylhydroquinone and a di‐fluoro monomer under pseudo high dilution condition. Novel aromatic fully MC‐PI oligomers were successfully prepared by the reaction of 2,3,3′,4′‐biphenyltetracarboxylic diandhydride with 2,5‐bis(4′‐aminophenoxy)‐biphenyl and sulfur‐containing macrocycle of aryl ether ketone. The MC‐PI oligomers were cross‐linkable in the heating, and the glass transition temperatures of the polyimides increased after thermally cured. The cross‐linking reaction of MC‐PI could form fully aromatic thermosetting polyimide by ring‐opening reaction. After cross‐linking, these polyimides showed higher glass transition temperatures and excellent thermal stability. Copyright © 2013 John Wiley & Sons, Ltd.
Early glycaemic control is predictive of long‐term control: a retrospective observational study
Authors: Jackson C , Wernham EM , Elder CJ , Wright NP
Published: January 2013

There is a paucity of long‐term data examining the relationship between early glycaemic control, in children and young people diagnosed with type 1 diabetes mellitus (T1DM), and long‐term control. We wanted to determine whether early glycaemic control can predict long‐term control. In addition, we examined whether initial presentation with ketoacidosis predicts future control.

A retrospective observational study of 155 children diagnosed with T1DM was undertaken examining HbA1c values collected over a 14‐year period (1990–2004). HbA1c levels at diagnosis, over the first year after diagnosis and subsequent HbA1c were analysed by Pearson Correlation and multiple regression analysis to determine whether early glycaemic control is predictive of future, long‐term control.

The cohort of 155 (81 male) currently aged between 2.4–18.3 years had a mean age at diagnosis of 6.6 years, with a mean duration of diabetes of 5.0 years. HbA1c levels at diagnosis (correlation coefficient 0.351, p < 0.05) and within the first year (correlation coefficient 0.438, p < 0.001) were significant predictors of long‐term control; diabetic ketoacidosis at presentation had no predictive value (correlation coefficient ‐0.096, p=0.326). Multiple regression analysis indicated that the mean HbA1c level within the first year was the best predictor of the long‐term HbA1c (r2 = 0.471).

Early glycaemic control is predictive of long‐term control. Health professionals seek to identify critical points in the evolution of T1DM at which to intervene in the hope of improving outcome, and this study identifies the first year as such a critical time. Copyright © 2013 John Wiley & Sons.
Comparison of daytime 12‐hour metabolic profiles after treatment with repaglinide and gliclazide in type 2 diabetes
Authors: Peter R , Dunseath G , Luzio SD , Owens DR
Published: January 2013

This study aimed to compare the effect of repaglinide and gliclazide on glucose and pancreatic beta‐cell secretory products in response to serial test meals, over a 12‐hour period during the day, in patients with type 2 diabetes (T2DM).

T2DM subjects (n=12), on metformin and repaglinide three times a day preprandially, underwent baseline 12‐hour glucose and hormonal (specific insulin and intact proinsulin) daytime profiles in response to three identical standard 500kcal test meals 4?hours apart. Subjects were then switched from repaglinide to twice‐daily gliclazide for the study period of three months, after which the 12‐hour profiles were repeated under identical conditions.

Fasting plasma glucose, insulin and intact proinsulin concentrations were similar with the two treatments. Postprandial glucose excursions were significantly lower with repaglinide for both Meals 1 and 2 (both p < 0.05). Insulin to glucose ratios were significantly greater with repaglinide in response to Meal 1 (p < 0.01). Postprandial insulin and intact proinsulin (all p < 0.01) responses were also significantly higher with repaglinide after the first meal.

Repaglinide is a more potent and shorter‐acting insulin secretagogue but its effects are predominantly in response to the first meal of the day, which may be influenced by the relatively higher beta‐cell secretory capacity after a period of fasting. Copyright © 2013 John Wiley & Sons.
Lattice dynamics of short‐period AlN/GaN superlattices: Theory and experiment
Authors: Davydov V. Yu. , Roginskii E. M. , Smirnov A. N. , Kitaev Yu. E. , Yagovkina M. A. , Kyutt R. N. , Rozhavskaya M. M. , Zavarin E. E. , Lundin W. V. , Smirnov M. B.
Published: January 2013

We report on the first observation of folded acoustic phonons in the Raman spectra of short‐period AlN/GaN superlattices (SLs). The values of longitudinal and transverse sound velocities along the [0001] direction of SL were estimated. It is shown that the SL period can be evaluated from Raman data with a good accuracy. Ab initio calculations of the zone‐center phonons in (AlN)n(GaN)n SLs with the number of monolayer equal to n = 2,4,6 were performed. The frequencies of phonon modes were calculated and the mode displacement patterns have been established. The theoretical Raman spectra were simulated and compared with experimental ones. A strong sensitivity of A1(LO) phonons confined within the AlN layer to its thickness was revealed both experimentally and in calculations. This finding can be used for quantitative characterization of short‐period AlN/GaN SLs.