Crossover learning of gestures in two ideomotor apraxia patients: A single case experimental design study

Crossover learning may aid rehabilitation in patients with neurological disorders. Ideomotor apraxia (IMA) is a common sequela of left-brain damage that comprises a deficit in the ability to perform gestures to verbal commands or by imitation. This study elucidated whether crossover learning occurred in two post-stroke IMA patients without motor paralysis after gesture training approximately 2 months after stroke onset. We quantitatively analysed the therapeutic intervention history and investigated whether revised action occurred during gesture production. Treatment intervention was to examine how to influence improvement and generalisation of the ability to produce the gesture. This study used an alternating treatments single-subject design, and the intervention method was errorless learning. Results indicated crossover learning in both patients. Qualitative analysis indicated that revised action occurred during the gesture-production process in one patient and that there were two types of post-revised action gestures: correct and incorrect gestures. We also discovered that even when a comparably short time had elapsed since stroke onset, generalisation was difficult. Information transfer between the left and right hemispheres of the brain via commissural fibres is important in crossover learning. In conclusion, improvements in gesture-production skill should be made with reference to the left cerebral hemisphere disconnection hypothesis.     

Significance of subcentimetre 18F-FDG PET/CT pulmonary abnormality in patients with known extrapulmonary malignancy

The significance of a subcentimetre ¹⁸F-FDG PET/CT pulmonary abnormality in a patient with known extrapulmonary primary malignancy can have a major impact on the clinical management of the patient. The clinician’s reliance on the semi-quantitative and qualitative PET/CT analysis of the abnormality has, at times, led to untoward diagnostic problems, given the limited spatial resolution of PET for a small volume lesion performed as part of the standard PET/CT study. This paper highlights a case each of an FDG-positive and an FDG-negative focal pulmonary abnormality in a combined PET/CT study of patients with known extrapulmonary malignancy. © 2010 Biomedical Imaging and Intervention Journal. All rights reserved.     

硫氧还原蛋白结合蛋白基因多态性与精神分裂症的关联分析

目的探索硫氧还原蛋白结合蛋白（TXNIP）基因与精神分裂症的关联关系。方法以182个精神分裂症核心家系为研究对象，应用聚合酶链反应和限制性片段长度多态性技术（PCR-RFLP）对TXNIP基因标签单核苷酸多态性（htSNP）rs9245进行基因分型；使用传递不平衡（TDT）、基于单体型的单体型相对危险度分析（HHRR）检测TXNIP基因与精神分裂症之间的关联关系。结果①患者组、父母组htSNP rs9245位点各基因型的分布均符合Hardy-Weinberg平衡法则（矿值分别为0．68，0．02，df=1，P〉0．05）；②单体型相对风险分析（HHRR）显示htSNP rs9245位点等位基因在患者组和父母组的频数分布为χ^2=3．42，P=0．064；③传递不平衡检验（TDT）分析显示，杂合子父母传递给受累子女与非传递等位基因频率分布为χ^2=3．40，P=0．065，虽然差异未达到显著性，但接近边缘显著性。结论本研究虽未发现TXNIP基因htSNP rs9245与精神分裂症的发生存在关联，但不能排除两者的阳性关联，尚需选择更多SNP及扩大样本量进一步分析。     

Joint analysis of individual participants’ data from 17 studies on the association of the IL6 variant -174G>C with circulating glucose levels,interleukin-6 levels,and body mass index

Background. Several studies have investigated associations between the -174G>C single nucleotide polymorphism (rs1800795) of the IL6 gene and phenotypes related to type 2 diabetes mellitus (T2DM) but presented inconsistent results.

Aims. This joint analysis aimed to clarify whether IL6 -174G>C was associated with glucose and circulating interleukin-6 concentrations as well as body mass index (BMI).

Methods. Individual-level data from all studies of the IL6-T2DM consortium on Caucasian subjects with available BMI were collected. As study-specific estimates did not show heterogeneity (P>0.1), they were combined by using the inverse-variance fixed-effect model.

Results. The main analysis included 9440, 7398, 24,117, or 5659 non-diabetic and manifest T2DM subjects for fasting glucose, 2-hour glucose, BMI, or circulating interleukin-6 levels, respectively. IL6 -174 C-allele carriers had significantly lower fasting glucose (?0.091 mmol/L, P=0.014). There was no evidence for association between IL6 -174G>C and BMI or interleukin-6 levels, except in some subgroups.

Conclusions. Our data suggest that C-allele carriers of the IL6 -174G>C polymorphism have lower fasting glucose levels on average, which substantiates previous findings of decreased T2DM risk of these subjects.     

Applicability of the single equivalent point dipole model to represent a spatially distributed bio-electrical source

Although the single equivalent point dipole model has been used to represent well-localised bio-electrical sources, in realistic situations the source is distributed. Consequently, position estimates of point dipoles determined by inverse algorithms suffer from systematic error due to the non-exact applicability of the inverse model. In realistic situations, this systematic error cannot be avoided, a limitation that is independent of the complexity of the torso model used. This study quantitatively investigates the intrinsic limitations in the assignment of a location to the equivalent dipole due to distributed electrical source. To simulate arrhythmic activity in the heart, a model of a wave of depolarisation spreading from a focal source over the surface of a spherical shell is used. The activity is represented by a sequence of concentric belt sources (obtained by slicing the shell with a sequence of parallel plane pairs), with constant dipole moment per unit length (circumferentially) directed parallel to the propagation direction. The distributed source is represented by N dipoles at equal arc lengths along the belt. The sum of the dipole potentials is calculated at predefined electrode locations. The inverse problem involves finding a single equivalent point dipole that best reproduces the electrode potentials due to the distributed source. The inverse problem is implemented by minimising the χ² per degree of freedom. It is found that the trajectory traced by the equivalent dipole is sensitive to the location of the spherical shell relative to the fixed electrodes. It is shown that this trajectory does not coincide with the sequence of geometrical centres of the consecutive belt sources. For distributed sources within a bounded spherical medium, displaced from the sphere's centre by 40% of the sphere's radius, it is found that the error in the equivalent dipole location varies from 3 to 20% for sources with size between 5 and 50% of the sphere's radius. Finally, a method is devised to obtain the size of the distributed source during the cardiac cycle.     

No evidence for a role of the coding variant of the Toll-like receptor 4 gene in temporal lobe epilepsy

PurposeThere is evidence that inflammatory mechanisms play a role in the pathogenesis of temporal lobe epilepsy (TLE). Coding variants in Toll-like receptor 4 (TLR4) gene have been reported to be associated with inflammatory diseases. The aim of this study was to determine whether a functional polymorphism rs4986790 in the TLR4 gene is associated with susceptibility and clinical features of TLE.MethodsA total of 345 patients with TLE and 370 age-matched controls were genotyped using TaqMan Allelic Discrimination assays, on an Applied Biosystems PCR platform.ResultsThere was no significant difference in allele frequency or genotype of TLR4 between TLE patients and controls. Moreover, the clinical characteristics of these patients were unrelated to the presence of this polymorphism.ConclusionOur data suggest that rs4986790 in the TLR4 gene is unlikely to influence significantly the risk of developing TLE or its severity.     

Internal retraction in single-port laparoscopic cholecystectomy: Initial experience and learning curve

Abstract

Introduction: We report our experience and learning curve in single-port laparoscopic cholecystectomy (SPLC) using an internal anchored retraction system. Methods: Usefulness of the retraction system was analysed in 18 SPLC. The first eight, the following ten SPLC and 20 consecutive four-port laparoscopic cholecystectomies (4PLC) were compared. Duration of operation, burns on nontarget tissue and gallbladder perforations were assessed by reviewing videotapes recorded during the procedures. Results: Use of the retraction system failed in three out of five patients (60%) with intraoperative signs of chronic inflammation and in one out of 13 (7.1%) without such signs (p = 0.0441). Median operation time was 90 (45–120) in the first eight and 55 (40–180) minutes in the following ten SPLC (p = 0.0361). Whereas the first eight SPLC lasted longer compared to 4PLC (70 (40–140) minutes, p = 0.0435) the difference disappeared after eight procedures (p = 0.2076). Median number of burns to nontarget tissue was seven (1–16) in the first eight and one (0–8) in the following ten SPLC (p = 0.0049). There was no difference in perforation of the gallbladder. Discussion: Internal retraction enables a safe exposure of the Calot triangle avoiding bile spillage in cholecystectomies without intraoperative signs of inflammation. Familiarisation with SPLC was rapidly achieved. Operation time and dexterity were equal to 4PLC after eight SPLC.     

一种新的PCR产物克隆方法——DI/TRISEC

ＰＣＲ产物的克隆。方法通过ＤＩ／ＴＲＩＳＥＣ法克隆ＰＣＲ产物。结果ＰＣＲ产物被高效定向地克隆。结论ＤＩ／ＴＲＩＳＥＣ是一种方便和高效的ＰＣＲ产物克隆方法。     

Comparison of single,homologous prime-boost and heterologous prime-boost immunization strategies against H5N1 influenza virus in a mouse challenge model

Preparation for an H5N1 influenza pandemic in humans may involve priming the population with a vaccine produced from an existing, available H5N1 strain. We have used a mouse challenge model to compare the immunogenicity and efficacy of inactivated, Vero cell-derived, whole virus H5N1 vaccines in single immunization and homologous or heterologous prime-boost regimes. A single immunization was sufficient to protect against a lethal challenge with strains from matched and unmatched H5N1 clades. Homologous and heterologous prime-boost regimes induced cross-neutralizing antibodies and cross-protection against representative viruses of H5N1 clade 1, clade 2.1, clade 2.2 and clade 2.3. Moreover, the results indicate that heterologous prime-boost immunization regimes might broaden the specificity of the anti-H5N1 antibody response.