bluuebunny/crossref_metadata_2025 huggingface dataset:
Symptomatic treatment in the fragile X–associated tremor/ataxia syndrome
Authors: Hall Deborah A. , Berry‐Kravis Elizabeth , Hagerman Randi J. , Hagerman Paul J. , Rice Cathlin D. , Leehey Maureen A.
Published: June 2006

There is no established treatment for the neurological features of the recently discovered fragile X–associated tremor/ataxia syndrome (FXTAS). Fifty‐six patients with FXTAS completed a questionnaire to determine whether any medications had been effective for neurological symptoms. Of 11 subjects with definite FXTAS, 8 (70%) were on medications for their neurological symptoms, whereas most subjects with possible or probable FXTAS, 31 (70%) of 45 subjects, were not on medications. Although no therapy was uniformly effective for intention tremor, ataxia, Parkinsonism, memory loss, or anxiety, some subjects with intention tremor or Parkinsonism reported improvement with medications frequently used in other movement disorders. Overall, all 22 subjects on medications reported improvement in one or more symptoms. Lack of insight, recall bias, and cognitive impairment may have resulted in an underestimation of the beneficial effect of medical therapy. This study suggests that patients with FXTAS can derive improvement from medication treatment for some of their symptoms. © 2006 Movement Disorder Society
Excessive daytime sleepiness in patients with Parkinson's disease: A polysomnography study
Authors: Shpirer Isaac , Miniovitz Ala , Klein Colin , Goldstein Richard , Prokhorov Tatiana , Theitler Jack , Pollak Lea , Rabey Jose Martin
Published: June 2006

To investigate excessive daytime sleepiness (EDS) in patients with Parkinson's disease (PD), the reasons for which have not yet been clarified, polysomnography (PSG) and the Multiple Sleep Latency Test (MSLT) were performed in 46 patients with PD, and, in addition, PSG was performed in 30 healthy controls. Assessment included Epworth Sleepiness Score (ESS), Mini‐Mental State Examination (MMSE), and Hamilton Test (HT) for depression. Fifty percent of PD patients reported EDS (ESS, 10 ± 4.5 vs. 6.9 ± 3.7; P = 0.01). Compared with controls, PD patients as a group had lower sleep efficiency (65 ± 22 vs. 77 ± 14; P = 0.03), a longer Stage 2 (73 ± 12 vs. 67 ± 12; P = 0.03), and a shorter rapid eye movement stage (8 ± 8 vs. 17 ± 8; P < 0.001). Clinical data and sleep characteristics were similar in PD with/without EDS. Of interest, patients treated with clonazepam (CLNZ) had lower EDS than those without CLNZ (ESS, 7.9 ± 4.7 vs. 11.3 ± 4.0; P = 0.03). These patients suffered less periodic leg movement during sleep (2.1 ± 2.7 vs. 12.4 ± 28; P = 0.04), which might explain the finding. No correlation was found between ESS, MSLT, and all other clinical features analyzed. In PD patients, according to the data obtained, severity of EDS does not depend on any specific clinical factor and the etiology is probably multifactorial. Paradoxically, PD patients treated with CLNZ were less sleepy than patients not treated with CLNZ. © 2006 Movement Disorder Society
Special low‐protein foods ameliorate postprandial off in patients with advanced Parkinson's disease
Authors: Barichella Michela , Marczewska Agnieszka , De Notaris Roberta , Vairo Antonella , Baldo Cinzia , Mauri Andrea , Savardi Chiara , Pezzoli Gianni
Published: June 2006

Protein intake interferes with levodopa therapy. Patients with advanced Parkinson's disease (PD) should restrict daily protein intake and shift protein intake to the evening. For further reduction of protein intake in the first part of the day, special low‐protein products (LPP) should be used instead of normal food products at breakfast and lunch. We studied the efficacy of LPP on postprandial off periods, in PD patients on levodopa therapy. The methods included a randomized, cross‐over, single‐blind, pilot clinical trial comparing a 2‐month balanced diet with a 2‐month LPP diet in 18 PD patients with motor fluctuations. The off phases were significantly shorter after LPP diet than after balanced diet (postprandial off, 49 ± 73 min vs. 79 ± 72 min and total off, 164 ± 148 min vs. 271 ± 174 min, both P < 0.0001). Moreover, a reduction in total off time during LPP diet (3.3 ± 2.7 hr vs. 4.7 ± 3.3 hr, P < 0.0001), occurred also in the 9 patients who did not experience subjective benefit. No significant changes in hematological and biochemical variables or body composition were recorded; a slight reduction in body weight (mean, −1.8%) was observed. Consumption of LPP in the first part of the day ameliorates off periods in PD patients, but additional studies including pharmacokinetics are needed. © 2006 Movement Disorder Society
Chemical exposures and Parkinson's disease: A population‐based case–control study
Authors: Frigerio Roberta , Sanft Kevin R. , Grossardt Brandon R. , Peterson Brett J. , Elbaz Alexis , Bower James H. , Ahlskog J. Eric , De Andrade Mariza , Maraganore Demetrius M. , Rocca Walter A.
Published: June 2006

The putative association between pesticide exposures and Parkinson's disease (PD) remains controversial. We identified all subjects who developed PD in Olmsted County, Minnesota, from 1976 through 1995, and matched them by age (± 1 year) and sex to general population controls. We assessed exposures to chemical products by means of telephone interview with cases, controls, or their proxies (149 cases; 129 controls). Exposure to pesticides related or unrelated to farming was associated with PD in men (odds ratio, 2.4; 95% confidence interval, 1.1–5.4; P = 0.04). The association remained significant after adjustment for education or smoking. Analyses for the other six categories of industrial and household chemicals were all nonsignificant. This population‐based study suggests a link between pesticides use and PD that is restricted to men. Pesticides may interact with other genetic or nongenetic factors that are different in men and women. © 2006 Movement Disorder Society
Factors influencing flip angle mapping in MRI: RF pulse shape, slice‐select gradients, off‐resonance excitation, and B0 inhomogeneities
Authors: Wang Jinghua , Mao Weihua , Qiu Maolin , Smith Michael B. , Constable R. Todd
Published: June 2006

To understand the various effects that influence actual flip angles, and correct for these effects, it is important to precisely quantify the MRI parameters (such as T1, T2, and perfusion). In this paper actual flip angle maps are calculated using a conventional gradient‐echo (GRE) sequence with different radiofrequency (RF) pulse shapes (Gaussian, sinc, and truncated‐sinc), slice‐selection gradients, off‐resonance excitations, and B0 field inhomogeneities. The experimental results demonstrate that RF pulse shapes significantly affect the flip angle distribution and calibration factors. Off‐resonance RF excitations, B0 nonuniformities, and slice‐selection gradients can lead to degradations in the signal intensities of the images used to map the flip angle, and potentially introduce a bias and increased variance in the measured flip angles. Magn Reson Med, 2006. © 2006 Wiley‐Liss, Inc.
Measurement of short and ultrashort T2 components using progressive binomial RF saturation
Authors: Ropele Stefan , Enzinger Christian , Seifert Thomas , Fazekas Franz
Published: June 2006

A new magnetic resonance (MR) method for measuring T2 relaxation times in tissues is proposed. The method is based on a T2 selective saturation period followed by sampling of the remaining longitudinal magnetization. Saturation of the longitudinal magnetization is accomplished by a single binomial RF pulse of zeroth order with a constant flip angle. The T2 selectivity is controlled by the RF pulse duration. A full T2 spectrum can be obtained by performing a series of measurements with varying RF pulse duration. On a conventional 1.5 T system this approach allows detection of T2 components as short as several hundred microseconds. A major limitation is the method's susceptibility to resonance offsets. At typical offsets of 0.1–0.2 ppm the sensitivity of the method is limited to a T2 range below 20 ms, which corresponds to an RF pulse duration shorter than 50 ms. The new method was used to acquire T2 spectra from the liver of pigs in vitro on a conventional 1.5 T system. We observed a short T2 component around 17 ms and an ultrashort T2 component in the range of 0.9–1.1 ms. Numerical simulations and in vitro measurements suggest that resonance offsets have effects that require further investigation. Magn Reson Med, 2006. © 2006 Wiley‐Liss, Inc.
Resolution and SNR effects on carotid plaque classification
Authors: Ronen Raphael R. , Clarke Sharon E. , Hammond Robert R. , Rutt Brian K.
Published: June 2006

Multicontrast‐weighted MRI, which is increasingly being used in combination with automatic classification algorithms, has the potential to become a powerful tool for assessing plaque composition. The current literature, however, does not address the relationship between imaging conditions and segmentation viability well. In this study 13 carotid endarterectomy samples were imaged with a 156‐μm in‐plane resolution and high signal‐to‐noise ratio (SNR) using proton density (PD), T1, T2, and diffusion weightings. The maximum likelihood (ML) algorithm was used to classify plaque components, with sets of three contrast weighting intensities used as features. The resolution and SNR of the images were then degraded. Classification accuracy was found to be independent of in‐plane resolution between 156 μm and 1250 μm, but dependent on SNR. Accuracy decreased less than 10% for degradation in SNR down to 25% of original values, and decreased sharply thereafter. The robustness of automatic classifiers makes them applicable to a wide range of imaging conditions, including standard in vivo carotid imaging scenarios. Magn Reson Med, 2006. © 2006 Wiley‐Liss, Inc.
Approximate dynamic programming methods for an inventory allocation problem under uncertainty
Authors: Topaloglu Huseyin , Kunnumkal Sumit
Published: June 2006

We propose two approximate dynamic programming methods to optimize the distribution operations of a company manufacturing a certain product at multiple production plants and shipping it to different customer locations for sale. We begin by formulating the problem as a dynamic program. Our first approximate dynamic programming method uses a linear approximation of the value function and computes the parameters of this approximation by using the linear programming representation of the dynamic program. Our second method relaxes the constraints that link the decisions for different production plants. Consequently, the dynamic program decomposes by the production plants. Computational experiments show that the proposed methods are computationally attractive, and in particular, the second method performs significantly better than standard benchmarks. © 2006 Wiley Periodicals, Inc. Naval Research Logistics, 2006
Stress intensity factor computation using the method of fundamental solutions: mixed‐mode problems
Authors: Berger J. R. , Karageorghis Andreas , Martin P. A.
Published: June 2006

The method of fundamental solutions is applied to the computation of stress intensity factors in linear elastic fracture mechanics. The displacements are approximated by linear combinations of the fundamental solutions of the Cauchy–Navier equations of elasticity and the leading terms for the displacement near the crack tip. Two algorithms are developed, one using a single domain and one using domain decomposition. Numerical results are given. Copyright © 2006 John Wiley & Sons, Ltd.
Molecular simulation of the glass transition and proton conductivity of 2,2′‐benzidinedisulfonic acid and 4,4′‐diaminodiphenylether‐2,2′‐disulfonic acid‐based copolyimides as polyelectrolytes for fuel cell applications
Authors: Hu Naiping , Chen Rongrong , Hsu Andrew
Published: June 2006

The glass transition temperatures (Tgs) and proton conductivities of polyimides synthesized from naphthalene‐1,4,5,8‐tetracarboxylic dianhydride (NTDA), 2,2′‐benzidinedisulfonic acid (BDSA), 4,4′‐diaminodiphenylether‐2,2′‐disulfonic acid (ODADS), and non‐sulfonated diamine monomers have been predicted using molecular dynamics simulations. The specific volumes for two dry and four hydrated NTDA‐based polyimides were plotted versus temperatures above and below Tgs to obtain the glass transition temperatures. The simulation results suggest that the ODADS‐based polyimide membranes exhibit lower Tgs and thus better mechanical properties than the BDSA‐based polyimides, which may be attributed to the high mobility of backbones of ODADS as supported by the vectorial autocorrelation function (VACF) results of this study. In addition, comparison of the simulated Tgs for the dry and hydrated ODADS‐based polyimides has shown that water content in polyimides can affect their Tgs. The proton conductivities of a representative polyimide in both dry and hydrated conditions have been obtained from molecular dynamics simulations of the proton and hydronium ion diffusion. The simulated conductivity for the hydrated NTDA‐ODADS/BAPB cell is in reasonable agreement with the experimental value obtained from the AC impedance method. The relationship between the chemical composition, chain flexibility, and the glass transition and proton conduction of these NTDA‐based polyimides was explored on the basis of VACF and pair correlation function analysis. Copyright © 2006 Society of Chemical Industry
Chemical and electrochemical synthesis of conducting graft copolymer of acrylonitrile with aniline
Authors: Hosseini S Hossein , Dabiri M , Ashrafi M
Published: June 2006

A new conducting copolymer, polyacrylonitrile‐graft‐polyaniline (PAN‐g‐PANi), has been prepared by chemical and electrochemical methods from a precursor polymer. Poly[acrylonitrile‐co‐(acrylimine phenylenediamine)] (PAN‐co‐PAIPD) was synthesized chemically by reacting PAN with sodium 1,4‐phenylenediamine salt. PAN‐g‐PANi was synthesized chemically using ammonium peroxydisulfate as the oxidant and p‐toluenesulfonic acid in dimethylsulfoxide solution and adding aniline to oxidized PAN‐co‐PAIPD. Electrochemical polymerization was carried out by spin coating PAN‐co‐PAIPD on the surface of a Pt electrode, then the growth of the graft copolymer (PAN‐g‐PANi) in the presence of fresh aniline and acidic solution. The structures of the graft copolymer and PAN‐co‐PAIPD were characterized using UV‐visible, Fourier transform infrared, and 1H and 13C NMR spectroscopies. The thermal properties of PAN‐g‐PANi were studied using thermogravimetric analysis and differential scanning calorimetry. Scanning electron microscopy (SEM) images showed that the morphology of PAN‐g‐PANi copolymer films was homogeneous. Electrical conductivity of the copolymer was studied using the four‐probe method, which gave a conductivity of 4.5 × 10−3 S cm−1 with 51.4% PANi. SEM and electrical conductivity measurements supported the formation of the graft copolymer. Copyright © 2006 Society of Chemical Industry
Morphologies and properties of epoxy resin/layered silicate–silica nanocomposites
Authors: Jia Qingming , Zheng Maosheng , Cheng Jun , Chen Hongxiang
Published: June 2006

A new nanofiller containing layered organo‐modified montmorillonite (oMMT) and spherical silica (SiO2) was prepared by an in situ deposition method and coupling agent modification. Fourier transform infrared spectrometry, X‐ray diffraction and transmission electron microscopy show that there are interactions between oMMT and SiO2, and the spherical SiO2 particles are self‐assembled on the edge of oMMT layers, forming a novel layered–spherical nanostructure. An epoxy resin (EP)/oMMT–SiO2 nanocomposite was obtained by adding oMMT–SiO2 to EP matrix. Morphologies and mechanical and thermal properties of the new ternary nanocomposite were investigated. For purposes of comparison, the corresponding binary nanocomposites, i.e., EP modified with either oMMT or SiO2, were also tested. The results for the mechanical properties show that oMMT obviously improves the strength of EP, and SiO2 enhances the toughness of EP, but oMMT–SiO2 exhibits a synergistic effect on toughening and reinforcing of EP. The toughening and reinforcing mechanism is explained by scanning electron microscopy. In addition, the thermal resistance of EP/oMMT–SiO2 is better than that of EP/SiO2, but it is worse than that of EP/oMMT. Copyright © 2006 Society of Chemical Industry
Retracted: Preparation and characterization of nitrile rubber/poly(vinyl chloride)/organoclay nanocomposites
Authors: Shokri Ahmad Ali
Published: June 2006

Retracted: A. Shokri. Preparation and characterization of nitrile rubber/poly (vinyl chloride)/organoclay nanocomposites, Polymer International. [DOI: 10.1002/pi.2076].
The above article, published online in EarlyView on 13 June 2006, has been retracted for legal reasons.
Molecular and collective relaxations of ferroelectric side chain liquid crystalline polysiloxanes
Authors: Hsiue Ging‐Ho , Lee Rong‐Ho
Published: June 2006

The influences of mesogenic group chemical structures on dielectric relaxation behavior were investigated for ferroelectric side chain liquid crystalline polymers (FLCPs). The relaxation time and activation energies of the Goldstone mode, α‐, and β‐relaxations decrease with increasing spacer length because of the plasticizer effect of the spacer. Moreover, the relaxation intensity increases with increasing spacer length for FLCPs. An FLCP with a longer spacer length exhibits a higher mesogenic group mobility, and subsequently leads to easier reorientation toward the alternating electrical field. An increase in mesogenic core rigidity results in an increase in the relaxation time and activation energies, and a decrease in the relaxation intensities for the Goldstone mode, α‐, and β‐relaxations. Moreover, the β‐relaxation is suppressed and cannot be observed in the glassy state for FLCPs containing naphthyl biphenylcarboxylate as the mesogenic group. Shorter relaxation time, smaller activation energies, and higher intensity of the α‐, and β‐relaxations were obtained for FLCPs containing chiral moiety with a flexible heptyl alkyl chain. However, the relaxation intensity of the Goldstone mode for FLCPs containing this chiral moiety was smaller than that for FLCPs containing the chiral moiety with a butyl alkyl chain. For FLCPs containing a chiral moiety with two asymmetrical centers, their Goldstone mode relaxation showed larger amplitude. The α‐ and β‐relaxations are suppressed for these FLCPs because of the dense packing and memory effect of the smectic phase. The relationship between the chemical structure of the mesogenic group and dielectric relaxations is discussed in great detail. © 2006 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 44: 2035–2049, 2006
Effects of Cry1Ac toxin of Bacillus thuringiensis and nuclear polyhedrosis virus of Helicoverpa armigera (Hübner) (Lepidoptera: Noctuidae) on larval mortality and pupation
Authors: Liu Xiaoxia , Zhang Qingwen , Xu Baoliang , Li Jiancheng
Published: June 2006

In the laboratory, the percentage mortality and pupation of Helicoverpa armigera (Hübner) were investigated when larvae were exposed to Cry1Ac of Bacillus thuringiensis Berliner, nuclear polyhedrosis virus of H. armigera (HaNPV) or Cry1Ac and HaNPV together. The results revealed that interactions between Cry1Ac and HaNPV varied with bioassay method and concentration of the suspension. When larvae were infected using a suspension containing both HaNPV and Cry1Ac, most combinations of Cry1Ac (62.5, 125 and 250 µg mL−1) and HaNPV (1.2 × 106, 6.0 × 106 and 3.0 × 107 PIB mL−1) showed an antagonistic effect. In the bioassay procedure where larvae were force fed diet containing Cry1Ac 48 h after being infected by HaNPV, interaction between Cry1Ac (0.5, 1, 2, 4 and 8 µg mL−1) and HaNPV (6.0 × 106 and 3.0 × 107 PIB mL−1) showed an additive effect, while combinations of Cry1Ac (0.5, 1, 2 and 4 µg mL−1) and HaNPV (1.2 × 106 PIB mL−1) showed an antagonistic effect. In the bioassay procedure where larvae being infected by HaNPV were fed on Cry1Ac diet from neonate to death or pupation, the results suggested that Cry1Ac and HaNPV showed an additive interaction. The percentage mortality was lower in the treatment of larvae infected by transgenic Bt cotton leaf discs containing HaNPV suspension than in the treatment of larvae by conventional cotton leaf discs containing HaNPV, while the pupation rate was higher. The combination of Bt cotton and HaNPV showed antagonism. The present results showed that a combination of Cry1Ac and HaNPV usually resulted in mortality levels greater than in the case of Cry1Ac but not greater than with the virus alone. Copyright © 2006 Society of Chemical Industry
Understanding genetics: Analysis of secondary students' conceptual status
Authors: Tsui Chi‐Yan , Treagust David F.
Published: June 2006

This article explores the conceptual change of students in Grades 10 and 12 in three Australian senior high schools when the teachers included computer multimedia to a greater or lesser extent in their teaching of a genetics course. The study, underpinned by a multidimensional conceptual‐change framework, used an interpretive approach and a case‐based design with multiple data collection methods. Over 4–8 weeks, the students learned genetics in classroom lessons that included BioLogica activities, which feature multiple representations. Results of the online tests and interview tasks revealed that most students improved their understanding of genetics as evidenced in the development of genetics reasoning. However, using Thorley's (1990) status analysis categories, a cross‐case analysis of the gene conceptions of 9 of the 26 students interviewed indicated that only 4 students' postinstructional conceptions were intelligible–plausible–fruitful. Students' conceptual change was consistent with classroom teaching and learning. Findings suggested that multiple representations supported conceptual understanding of genetics but not in all students. It was also shown that status can be a viable hallmark enabling researchers to identify students' conceptual change that would otherwise be less accessible. Thorley's method for analyzing conceptual status is discussed. © 2006 Wiley Periodicals, Inc. J Res Sci Teach 44: 205–235, 2007
Significance of HBV DNA in the Hepatic Parenchyma from Patients with Non‐B, Non‐C Hepatocellular Carcinoma
Authors: Nakai Takuya , Shiraishi Osamu , Kawabe Takashi , Ota Hideo , Nagano Hiroaki , Shiozaki Hitoshi
Published: June 2006

Introduction

The etiologic and prognostic factors for non‐B, non‐C hepatocellular carcinoma (HCC), which is defined by its seronegativity for both hepatitis B surface antigen and hepatitis C virus (HCV) antibody, remain unclear.

Methods

Nonneoplastic liver tissue from 46 patients with non‐B, non‐C HCC were examined for hepatitis B virus (HBV) DNA and HCV RNA using in situ hybridization. Recurrence‐free survival rates were compared between patients showing high or low HBV DNA expression. Other potential prognostic factors were examined as well.

Results

HBV DNA was detected in nonneoplastic liver specimens from 35 patents (76.1%), whereas HCV RNA was not detected in any case. In patents with high HBV DNA group expression, recurrence‐free survival rates at 1 and 5 years after onset were 68.8% and 13.8%, respectively; those with low expression had higher rates of 89.2% and 59.2%, respectively. Multivariate analysis identified high tumor stage (P = 0.042) and high HBV DNA expression (p = 0.014) as independent negative prognostic factors.

Conclusions

In many patients with non‐B, non‐C HCC, HBV DNA in the liver appears to be involved in the carcinogenesis, with intense HBV DNA expression predicting poor outcome for patients with these cancers.
Laparoscopic Cholecystectomy in Patients Aged 80 Years and Over
Authors: Kwon A‐Hon , Matsui Yoichi
Published: June 2006

Introduction

The aging population has led to a significant rise in the number of patients undergoing operations such as cholecystectomy. We have evaluated and compared the results of laparoscopic cholecystectomy (LC) in patients aged 80 years and over with those of patients aged between 65 and 79 years.

Methods

A total of 471 patients aged 65 to 79 years (group 1) and 45 patients aged ≥80 years (group 2) underwent LC. All patients underwent preoperative spiral computed tomography after intravenous infusion cholangiography and intraoperative cholangiography.

Results

There was a higher incidence of choledocholithiasis and gallbladder cancer in the patients ≥80 years of age. In addition, group 2 patients had a higher incidence of cardiopulmonary disease and higher American Association of Anesthesiology scores than did those in group 1. With respect to the conversion rate to open surgery, morbidity, mortality, and length of hospital stay, there were no significant differences between the two groups. There was a significantly higher incidence of positive bile cultures and gram‐negative rods in group 2 patients than in those in group 1.

Conclusions

Octogenarians tolerated LC well. Therefore, early elective LC should be encouraged to minimize morbidity and mortality in these elderly patients who have symptomatic cholelithiasis.
Comparison of Mechanical Bowel Obstruction Cases of Intra‐abdominal Tumor and Non‐tumoral Origin
Authors: Akcakaya Adem , Sahin Mustafa , Coskun Aytekin , Demiray Sinan
Published: June 2006

Introduction

Mechanical bowel obstruction cases constitute an important place in emergency health care services. In this study, bowel obstructions caused by intra‐abdominal tumors were compared with those without tumoral causes.

Patients and Methods

A total of 155 cases of mechanical bowel obstruction diagnosed were retrospectively evaluated. The cases resulting from abdominal wall hernias were excluded. Neoplasia cases were classified as group I, and all other cases as group II.

Results

Group I totaled 46 patients (30%); group II, 109 (70%). The difference between two groups in terms of gender was found to be statistically insignificant, but the difference in terms of age range was significant (P< 0.05). The etiology of group II cases included intra‐abdominal strictures (n = 68), volvulus (n = 15), internal herniation (n = 7), Meckel’s diverticulum (n = 7), tuberculous peritonitis (n = 4), foreign body (n = 4), invagination (n = 2), and inflammatory bowel disease (n = 2). Previous surgical operations had been performed in 9 patients (19%) of group I and 52 patients (47%) of group II. The difference between two groups in terms of bowel obstruction localization was significant (χ2: 37.78,P< 0.0001). Group I had a significantly higher morbidity and mortality than group II (P< 0.01 andP< 0.001).

Conclusions

Non‐tumoral cases causing intra‐abdominal mechanical bowel obstruction occur mostly in younger people and in patients with previous surgical operation. Patients in older ages or who haven’t had any surgical intervention must be operated as soon as possible because of the high rate of malignancy.
Penetrating Cardiac Injuries: Recent Experience in South Africa
Authors: Degiannis Elias , Loogna Peter , Doll Dietrich , Bonanno Fabrizio , Bowley Douglas M. , Smith Martin D.
Published: June 2006

Background

Penetrating cardiac injury is a dramatic and lethal form of trauma. The majority of patients will die before reaching medical care, but for those who arrive at hospital alive, the diagnostic acumen and rapid surgical intervention of physicians and surgeons can lead to successful outcomes.

Materials and Methods

A structured diagnostic and management approach is used in our trauma unit to deal with penetrating cardiac injury. A retrospective study of 117 patients with penetrating trauma to the heart was conducted over 32 months; the purpose of this study was to describe our protocol and review overall outcome with this type of injury. Demographic details, mechanism of injury, and mode of presentation were recorded. Mortality and morbidity data were collated and echocardiographic follow‐up was performed.

Results

There were 109 male patients, mean age 29 years (range: 15–54 years) and 8 female patients, mean age 35 years (range: 23–56 years). Most patients (96/117) had sustained stab wounds, and the associated mortality was 15.6%. Twenty‐one patients had sustained gunshot wounds (GSW), with a mortality of 81%. Gunshot wounds were significantly more likely to result in death (P ≤ 0.0001). Five patients sustained multiple cardiac wounds, and three of them died. The risk of death was not different between patients sustaining single or multiple cardiac wounds (P = 0.11). Eleven patients had thoracoabdominal injury, and 3/11 (27%) died; all of those that died had sustained GSW. The risk of death was not different between patients sustaining thoracoabdominal wounds and those with isolated thoracic injury (P = 1.0). Among the 51 patients with stab wounds who presented with cardiac tamponade, the mortality was only 8%. Compared to the other patients with stab wounds, cardiac tamponade conferred a significant survival advantage (P = 0.02).

Conclusions

A high index of suspicion for penetrating cardiac injury and an understanding of the modes of presentation can lead to rapid diagnosis even by inexperienced junior staff. Such a structured approach to patients with penetrating trauma to the chest leads to early definitive management and acceptable results.
Hand‐assisted Laparoscopic Surgery with a Pfannenstiel Incision in β‐Thalassemia Patients: Initial Experience
Authors: Leandros Emmanuel , Alexakis Nicholas , Albanopoulos Konstadinos , Dardamanis Dimitris , Karagiorga Markisia , Gomatos Ilias , Papadopoulos Stefanos , Bacoyiannis Christos , Bramis John
Published: June 2006

Introduction

β‐Thalassemia patients have splenomegaly significant enough to require splenectomy; furthermore, these patients also often require concurrent procedures.

Methods

Between January and October 2005, seven patients with β‐thalassemia underwent hand‐assisted laparoscopic splenectomy with cholecystectomy, appendectomy, and liver biopsy with the hand‐port device introduced through a Pfannenstiel incision.

Results

The median age of the patients was 28 years, and the median spleen length was 23 cm. The median operating time was 210 minutes; there were no conversions to an open procedure; and the median spleen weight was 1072 g. One major postoperative complication occurred. The median hospital stay was 6 days.

Conclusions

The proposed hand‐assisted laparoscopic approach is safe and feasible. It provides a minimally invasive alternative that may become the treatment of choice in β‐thalassemia patients who require concurrent operations.
Concomitant Detection of Systemic Atherosclerotic Disease while Screening for Abdominal Aortic Aneurysm
Authors: Waterhouse D.F. , Cahill R.A. , Sheehan F. , Sheehan S.J.
Published: June 2006

Introduction

Although population screening for abdominal aortic aneurysm (AAA) has/had a significant impact on disease‐specific mortality, coexisting systemic atherosclerosis represents the major impediment to improved longevity. We examined the feasibility and yield of full cardiovascular assessment concomitant with screening for AAA detection.

Methods

A total of 1032 asymptomatic men over the age of 50 years (328 were >60 years) underwent a detailed cardiac health questionnaire, sphygmomanometry, body mass index calculation, fasting lipid profiling, ultrasonographic (US) examination of their infrarenal aorta and carotid arteries, and treadmill exercise stress testing. Framingham and SCORE project estimations of the 10‐year risk of ischemic heart disease (IHD) and fatal cardiovascular disease (CVD) of any cause were calculated for the men with an AAA and in those >60 years but with neither AAA nor known cardiac disease.

Results

Overall, we detected an AAA >3 cm in 30 men (2.9%). Unaddressed obesity, smoking, hypertension, impaired glucose metabolism, and hypercholesterolemia were commonly identified in individuals both with and without an AAA, being notably frequent in those >60 years without an AAA. The 10‐year risk of IHD and CHD in those >60 years was similar regardless of whether an AAA was present. Doppler screening for significant carotid stenosis had detection rates similar to those for aortic US scanning, being most useful in those >65 years of age. Exercise stress testing, however, was of only limited value when used nonselectively.

Conclusions

Modifiable atherosclerotic disease and cardiovascular risk can be readily detected in individuals presenting for AAA screening and are present to a significant degree at an earlier age. Consideration of selected, additional investigations is required to maximize the value of generalized screening programs.
Sharpless Surgery: A Prospective Study of the Feasibility of Performing Operations using Non‐sharp Techniques in an Urban, University‐based Surgical Practice
Authors: Makary Martin A. , Pronovost Peter J. , Weiss Eric S. , Millman E. Anne , Chang David , Baker Susan P. , Cornwell Edward E. , Syin Dora , Freischlag Julie A.
Published: June 2006

Context

Percutaneous injuries occur frequently during surgical procedures and represent a significant occupational hazard to operating room personnel.

Objectives

To evaluate the feasibility of performing select general surgical procedures using a combination of non‐sharp devices and techniques to replace the conventional use of scalpels and needles.

Design, Setting, and Participants

Candidate procedures for which sharpless techniques could replace conventional scalpels and suture needles were identified preoperatively in an urban, university‐based general surgical practice over a 1‐year period (June 2003–June 2004). Non‐sharp techniques included monomeric 2‐octyl cyanoacrylate adhesive, electrocautery, tissue stapler, and minimally invasive instrumentation. Conventional scalpels and suture needles were readily available and used whenever necessary.

Main Outcome Measures

We rated the feasibility of performing specific procedures without sharps. We also documented the rate of overall reversion to sharps during operations on patients that had been identified preoperatively as candidates for sharpless surgery.

Results

Of 358 procedures performed in the general surgery university practice, 91 were identified preoperatively as appropriate for sharpless surgery. Of these, 86.8% (79/91) were completed without the use of sharps, including 13/22 (59.1%) open laparotomy procedures, 20/22 (90.9%) laparoscopic procedures, and 46/47 (97.8%) soft tissue procedures. Intraoperative reversion to sharps occurred in 12 cases when deemed necessary by the surgeon.

Conclusions

Select common procedures can be performed entirely with sharpless techniques, eliminating the risk to surgical personnel associated with intraoperative percutaneous injuries.
Stent‐graft Treatment for Isolated Infrarenal Aortic Dissecting Aneurysms
Authors: Caronno Roberto , Piffaretti Gabriele , Tozzi Matteo , Lomazzi Chiara , Rivolta Nicola , Laganà Domenico , Carrafiello Giampaolo , Cuffari Salvatore , Castelli Patrizio
Published: June 2006

Objectives

We report three cases of isolated infrarenal aortic dissecting aneurysms managed with stent‐graft.

Materials and Methods

Three patients, two men and one woman, with a mean age at diagnosis of 69 years were identified. In all cases, chest CT‐A did not reveal evidence of thoracic aortic dissection. The mean maximal aneurysm diameter was 6.7 ± 1.5 cm (range: 5.5–8 cm). All patients underwent stent‐graft repair. Follow‐up computed tomographic (CT)‐angiography examinations were scheduled 1, 4, and 12 months after the procedure.

Results

Stent‐graft deployment was technically successful in all cases. Intraoperative mortality was not observed. All patients were adequately treated with a bifurcated device. Intensive care unit (ICU) stay was never required. Mean hospitalization was 4.6 days (range: 4–6 days). Mean follow‐up was 18 months. No stent‐graft–related complications were observed.

Conclusions

Endovascular repair for isolated infrarenal abdominal aortic dissecting aneurysms is feasible and effective.
Moral competence and character strengths among adolescents: The development and validation of the Values in Action Inventory of Strengths for Youth
Authors: Park Nansook , Peterson Christopher
Published: June 2006

Moral competence among adolescents can be approached in terms of good character. Character is a multidimensional construct comprised of a family of positive traits manifest in an individual's thoughts, emotions and behaviours. The Values in Action Inventory for Youth (VIA‐Youth) is a self‐report questionnaire suitable for adolescents that measures 24 widely valued strength of character. Data from several samples bearing on the internal consistency, stability, and validity of the VIA‐Youth are described, along with what is known about the prevalence and demographic correlates of the character strengths it measures. Exploratory factor analysis revealed an interpretable four‐factor structure of the VIA‐Youth subscales: temperance strengths (e.g., prudence, self‐regulation), intellectual strengths (e.g., love of learning, curiosity), theological strengths (e.g., hope, religiousness, love), and other‐directed (interpersonal) strengths (e.g., kindness, modesty). The uses of the VIA‐Youth in research and practise are discussed along with directions for future research.
Psychometric properties of the MOS (Medical Outcomes Study) Sleep Scale in patients with neuropathic pain
Authors: Rejas Javier , Ribera María Victoria , Ruiz Manuel , Masrramón Xavier
Published: June 2006

Objective: This study assessed the psychometric properties of the MOS Sleep Scale in neuropathic pain (NeP).

Methods: Psychometric properties were tested in patients with neuropathic pain enrolled in a prospective study exploring the effectiveness of gabapentin for 3 months. Participants also completed scales for pain intensity, anxiety, depression, disability, and health‐related quality of life. Feasibility, reliability, validity and sensitivity to change were measured in this study.

Results: Six‐hundred‐three patients [58.4±14.4 years (65.1% female), mean±SD] with pain for 1.2±3.3 years were included. The MOS Sleep Scale was acceptable (items with missing data <10% and floor and ceiling effects <50% per item and <15% per domain) and reliable (Cronbach's α between 0.64 and 0.87, and test–retest intraclass correlation coefficients between 0.79 and 0.91, p<0.001 for all cases). After adjusting for confounders, the MOS Sleep Scale was able to distinguish between sex, present pain intensity, level of disability and presence of anxiety or depression. Correlations with other scales were moderate; ρ‐coefficients between −0.21 and 0.57 (p<0.01, all cases). The scale was sensitive to change after treatment with gabapentin; after adjusting, responders (≥50% reduction in baseline pain) showed a decrease in sleep problems index of −25.6±14.3 points vs. −12.1+14.5 points in nonresponders (F=80.5, df=1/398, p<0.0001). Score reduction in summary index and subscales correlated significantly with pain intensity reduction (Pearson r‐coefficients between 0.428 and 0.116, p<0.01, all cases).

Conclusions: The MOS Sleep Scale showed good psychometric properties and was sensitive to changes in patients with NeP of broad aetiology.
Induced‐fitting and electrostatic potential change of PcyA upon substrate binding demonstrated by the crystal structure of the substrate‐free form
Authors: Hagiwara Yoshinori , Sugishima Masakazu , Takahashi Yasuhiro , Fukuyama Keiichi
Published: June 2006

Phycocyanobilin:ferredoxin oxidoreductase (PcyA) catalyzes the sequential reduction of the vinyl group of the D‐ring and the A‐ring of biliverdin IXα (BV) using ferredoxin to produce phycocyanobilin, a pigment used for light‐harvesting and light‐sensing in red algae and cyanobacteria. We have determined the crystal structure of the substrate‐free form of PcyA from Synechocystis sp. PCC 6803 at 2.5 Å resolution. Structural comparison of the substrate‐free form and the PcyA–BV complex shows major changes around the entrance of the BV binding pocket; upon BV binding, two α‐helices and nearby side‐chains move to produce tight BV binding. Unexpectedly, these movements localize the positive charges around the BV binding site, which may contribute to the proper binding of ferredoxin to PcyA. In the substrate‐free form, the side‐chain of Asp105 was located at a site that would be underneath the BV A‐ring in the PcyA–BV complex and hydrogen‐bonded with His88. We propose that BV is protonated by a mechanism involving conformational changes of these two residues before reduction.
Amino acids 15–28 in the ectodomain of SARS coronavirus 3a protein induces neutralizing antibodies
Authors: Åkerström Sara , Tan Yee-Joo , Mirazimi Ali
Published: June 2006

A synthetic peptide corresponding to amino acids (aa) 15–28 of the severe acute respiratory syndrome coronavirus (SARS‐CoV) 3a protein was used to raise polyclonal antibodies in rabbits. This anti‐3a N‐terminal antibody could detect 3a protein in infected cells, as did an anti‐3a C‐terminal antibody previously described. The latter targeted the C‐terminal cytoplasmic domain of 3a (aa 134–274). The anti‐3a N‐terminal antibody could detect intracellular 3a as well as 3a expressed on the cell surface. Interestingly, only the anti‐3a N‐terminal antibody can inhibit SARS‐CoV propagation in Vero E6 culture although the binding affinity of the anti‐3a N‐terminal antibody was lower than the anti‐3a C‐terminal antibody.
Percutaneous Needle Fasciotomy in Dupuytren’s Disease
Authors: VAN RIJSSEN A. L. , WERKER P. M. N.
Published: June 2006

The aim of this study was to examine our results of 74 percutaneous needle fasciotomies for Dupuytren’s contracture. Pre-operative and postoperative total passive extension deficit was measured. Patients were seen at the outpatient clinic at 32 months for final follow-up. Extension deficit and sensibility were measured and flexor tendon function assessed. Recurrence, defined as an increase of the passive extension deficit of 30° or more compared to the immediate postoperative measurement, and other complications were also noted. Immediate outcome was excellent with an average improvement of 77%. After 32 months, we reviewed 55 rays. Their recurrence rate was 65%. Two patients experienced a slightly diminished sensibility on one side of the finger. There were no flexor tendon injuries. This procedure has a good short-term effect. It may be suitable for patients who want a minimally invasive treatment and to whom long-term results are less important. It may also have a place in delaying fasciectomy.
Reconstruction of Disruptions of the Deep Transverse Metacarpal Ligament of the Ring Finger Using the A1 Pulleys
Authors: JOSTY I. C. , LAING J. H. E. , DENT C.
Published: June 2006

There is little information in the literature regarding the clinical features, investigation, diagnosis and treatment of closed rupture of the deep transverse metacarpal ligament. We demonstrate a case with previously undescribed features and describe the surgical management.
Purification and characterization of a novel 3′-5′ DNA helicase fromPlasmodium falciparumand its sensitivity to anthracycline antibiotics
Authors: SUNTORNTHITICHAROEN P. , PETMITR S. , CHAVALITSHEWINKOON-PETMITR P.
Published: June 2006

Plasmodium falciparumhas developed resistance to most anti-malarials; therefore, an investigation of potential targets should be performed. DNA helicases are enzymes that catalyse the unwinding of double-stranded DNA to provide single-stranded templates for DNA replication, repair and recombination. In this study, a DNA helicase (PfDH A) was purified from a crude extract ofPlasmodium falciparum. DNA helicase activity was measured by assaying unwinding activity. The apparent molecular weight of PfDH A as determined by SDS-PAGE was 90 kDa. PfDH A moved unidirectionally in the 3′ -to- 5′ direction along the bound strand and preferred a fork-like substrate structure and could not unwind blunt-ended duplex DNA. Unwinding activity required Mg2+and could be inhibited by 200 mMNaCl or KCl and was dependent on hydrolysis of ATP or dATP. Anthracyclines, including daunorubicin, nogalamycin, doxorubicin, and aclarubicin, inhibited PfDH A activity with IC50values of 2, 5, 8 and 9 μM, respectively. Based on the results, PfDH A differs from all known human DNA helicases. However, its function and roles in parasite DNA replication need to be elucidated in the future.
Molecular structure of amyloid fibrils: insights from solid-state NMR
Authors: Tycko Robert
Published: June 2006

1. Introduction 2

2. Sources of structural information in solid-state NMR data 5

2.1 General remarks 5

2.2 Chemical shifts, linewidths, and magic-angle spinning 6

2.3 Dipole–dipole couplings and dipolar recoupling 8

2.4 Tensor correlation techniques 12

2.5 Solid-state NMR of aligned samples 14

2.6 Indirect sources of structural information 15

2.7 Sample preparation for solid-state NMR 15

3. Levels of structure in amyloid fibrils 18

4. Molecular structure of β-amyloid fibrils 25

4.1 Self-propagating, molecular-level polymorphism in Aβ1–40 fibrils 25

4.2 Structural model for Aβ1-40 fibrils 28

4.3 Staggering of β-strands in Aβ1-40 fibrils 32

4.4 Structure of Aβ1-42 fibrils 34

4.5 Structure of fibrils formed by short β-amyloid fragments 34

4.6 Structures of non-fibrillar aggregates 35

5. Molecular structure of other amyloid fibrils 36

5.1 Ure2p10–39 and full-length Ure2p fibrils 36

5.2 TTR105–115 fibrils 38

5.3 HET-s fibrils 38

5.4 Amylin fibrils 39

5.5 PrP fibrils 39

5.6 ccβ fibrils 40

5.7 α-synuclein fibrils 40

5.8 Calcitonin fibrils 41

6. Data relevant to various proposals regarding amyloid structure 41

6.1 β-helical models for amyloid fibrils 41

6.2 Amyloid fibrils as water-filled nanotubes 42

6.3 Domain swapping in amyloid fibrils 42

6.4 The parallel superpleated β-structure model 43

6.5 α-sheet structures in amyloid fibrils 43

7. Conclusions 44

8. Acknowledgments 46

9. References 46

Solid-state nuclear magnetic resonance (NMR) measurements have made major contributions to our understanding of the molecular structures of amyloid fibrils, including fibrils formed by the β-amyloid peptide associated with Alzheimer's disease, by proteins associated with fungal prions, and by a variety of other polypeptides. Because solid-state NMR techniques can be used to determine interatomic distances (both intramolecular and intermolecular), place constraints on backbone and side-chain torsion angles, and identify tertiary and quaternary contacts, full molecular models for amyloid fibrils can be developed from solid-state NMR data, especially when supplemented by lower-resolution structural constraints from electron microscopy and other sources. In addition, solid-state NMR data can be used as experimental tests of various proposals and hypotheses regarding the mechanisms of amyloid formation, the nature of intermediate structures, and the common structural features within amyloid fibrils. This review introduces the basic experimental and conceptual principles behind solid-state NMR methods that are applicable to amyloid fibrils, reviews the information about amyloid structures that has been obtained to date with these methods, and discusses how solid-state NMR data provide insights into the molecular interactions that stabilize amyloid structures, the generic propensity of polypeptide chains to form amyloid fibrils, and a number of related issues that are of current interest in the amyloid field.
Special polynomials associated with rational solutions of the defocusing nonlinear Schrödinger equation and the fourth Painlevé equation
Authors: CLARKSON PETER A.
Published: June 2006

Rational solutions and rational-oscillatory solutions of the defocusing nonlinear Schrödinger equation are expressed in terms of special polynomials associated with rational solutions of the fourth Painlevé equation. The roots of these special polynomials have a regular, symmetric structure in the complex plane. The rational solutions verify results of Nakamura and Hirota [J. Phys. Soc. Japan, 54 (1985) 491–499] whilst the rational-oscillatory solutions appear to be new solutions of the defocusing nonlinear Schrödinger equation.