Electrophysiological differences between upper and lower limb movements in the human subthalamic nucleus

ObjectiveFunctional processes in the brain are segregated in both the spatial and spectral domain. Motivated by findings reported at the cortical level in healthy participants we test the hypothesis in the basal ganglia of Parkinson’s disease patients that lower frequency beta band activity relates to motor circuits associated with the upper limb and higher beta frequencies with lower limb movements.MethodsWe recorded local field potentials (LFPs) from the subthalamic nucleus using segmented “directional” DBS leads, during which patients performed repetitive upper and lower limb movements. Movement-related spectral changes in the beta and gamma frequency-ranges and their spatial distributions were compared between limbs.ResultsWe found that the beta desynchronization during leg movements is characterised by a strikingly greater involvement of higher beta frequencies (24–31 Hz), regardless of whether this was contralateral or ipsilateral to the limb moved. The spatial distribution of limb-specific movement-related changes was evident at higher gamma frequencies.ConclusionLimb processing in the basal ganglia is differentially organised in the spectral and spatial domain and can be captured by directional DBS leads.SignificanceThese findings may help to refine the use of the subthalamic LFPs as a control signal for adaptive DBS and neuroprosthetic devices.     

The influence of polymorphisms in the drug transporter,ABCB1 on the toxicity of glucocorticoids in Saudi children with acute lymphoblastic leukaemia

Background

Glucocorticoids play essential roles in the treatment of childhood acute lymphoblastic leukaemia (ALL); however, treatment with these agents can result in severe side-effects. This study, the first of its kind in a Saudi population, investigates associations of ABCB1 gene polymorphisms (pharmacodynamics and pharmacokinetic) with the development of toxicity and side effects (glucose abnormality, liver toxicity and infection) in a small population of Saudi children with ALL.

Does CETP rs5882, rs708272, SIRT1 rs12778366, FGFR2 rs2981582, STAT3 rs744166, VEGFA rs833068, IL6 rs1800795 polymorphisms play a role in optic neuritis development?

Objectives: Optic neuritis (ON) is defined as inflammation of the optic nerve, which is mostly idiopathic. However, it can be associated with various causes (demyelinating lesions, autoimmune disorders, infectious and inflammatory conditions). Inflammatory demyelinating disorder of the optic nerve can be associated with multiple sclerosis. It is thought that CETP, SIRT1, FGFR2, STAT3, VEGFA and IL6 genes play a key role in this autoimmune inflammatory disease. The aim of our study was to determine if the frequency of the CETP, SIRT1, FGFR2, STAT3, VEGFA and IL6 gene polymorphisms have an influence on the development of acute ON.

Methods: The study enrolled patients with ON and a random sample of healthy population. The genotyping test of the CETPrs5882,rs708272, SIRT1rs12778366, FGFR2rs2981582, STAT3rs744166, VEGFArs833068, IL6rs1800795 polymorphisms was carried out using the RT-PCR method.

Results: Our study determined that the G/A genotype of CETPrs708272 was associated with two-fold-decreased odds of ON development under the codominant (OR = 0.495;95%CI:0.256–0.959) and overdominant (OR = 0.501;95%CI:0.280–0.895) models. Also, each allele C at VEGFArs833068 was associated with 1.7-fold increased odds of ON development under the additive model (OR = 1.733;95%CI:1.148–2.615). Furthermore, IL6 rs1800795 G/G genotype was associated with increased odds of ON development under the codominant (OR = 2.869;95%CI:1.280–6.434) and recessive (OR = 2.315;95%CI:1.251–4.285) models.

Conclusions: We revealed that the genotypes of CETPrs708272 G/A, IL6rs1800795 G/G, and each allele C at VEGFArs833068 were associated with ON. CETPrs708272 G/G genotype was associated with decreased by 62% odds of ON with MS development under the recessive (OR = 0.379;95%CI:0.155–0.929; p = .034) model.     

Inter-ictal assay of peripheral circulating inflammatory mediators in migraine patients under adjunctive cervical non-invasive vagus nerve stimulation (nVNS): A proof-of-concept study

Objective

To assay peripheral inter-ictal cytokine serum levels and possible relations with non-invasive vagus nerve stimulation (nVNS) responsiveness in migraineurs.

GATA6基因启动区多态性与急性心肌梗死患者易感性和临床特征的相关性分析

目的探讨GATA6基因启动区-493(rs144923558)G/A、-172(rs146748749)G/A 2个位点单核苷酸多态性(SNP)与急性心肌梗死(AMI)之间的关系及其相关的危险因素。方法采用病例-对照研究方法,收集328例AMI患者和344例正常对照;应用聚合酶链反应-限制性内切酶片段长度多态性技术结合DNA测序后的序列比对进行数据统计;运用Hardy-Weinberg平衡检验后,应用χ~2检验进行相关分析;利用Logistic回归对多种危险因素以及2个SNP位点与AMI发病进行关联性分析;利用Haplovview4.2软件和SHEsis网站进行连锁不平衡及单倍体分析。结果 2个SNP位点共检测出3种基因型为GG、GA和AA,其基因型分布均符合Hardy-Weinberg平衡(P0.05),同时在AMI组与对照组间差异无显著性(P0.05)。多因素Logistic回归分析:增龄、高血压病、吸烟、低密度脂蛋白胆固醇(LDLC)和甘油三酯(TG)升高是AMI发病的独立危险因素(P0.05),HDLC为保护因素(P0.05)。在显性、隐性和加性3种不同遗传模式下进行Logistic回归分析发现,2个SNP位点与AMI发病无关联性。进行连锁不平衡和单倍型分析提示,该2个SNP位点处于同一个连锁不平衡区域(D′=1.000,r~2=1.000),单倍型GG和AA均未增加AMI易感性(P0.05)。结论 GATA6基因启动区-493(rs144923558)G/A与-172(rs146748749)G/A两个SNP位点为完全连锁不平衡,其中GG为主要单倍型。该2个SNP位点及其单倍体型与AMI发病无相关性,但提供了GATA6基因启动区多态性的群体遗传学资料。     

The formation of physician patient sharing networks in medicare: Exploring the effect of hospital affiliation

This study explores the forces that drive the formation of physician patient sharing networks. In particular, I examine the degree to which hospital affiliation drives physicians' sharing of Medicare patients. Using a revealed preference framework where observed network links are taken to be pairwise stable, I estimate the physicians' pair‐specific values using a tetrad maximum score estimator that is robust to the presence of unobserved physician specific characteristics. I also control for a number of potentially confounding patient sharing channels, such as (a) common physician group or hospital system affiliation, (b) physician homophily, (c) knowledge complementarity, (d) patient side considerations related to both geographic proximity and insurance network participation, and (e) spillover from other collaborations. Focusing on the Chicago hospital referral region, I find that shared hospital affiliation accounts for 36.5% of the average pair‐specific utility from a link. Implications for reducing care fragmentation are discussed.     

Gene-Loaded Nanoparticle-Coated Sutures Provide Effective Gene Delivery to Enhance Tendon Healing

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Clinical features and possible founder mutation of the 8bp duplication mutation in the SLC4A11 gene causing corneal dystrophy and perceptive deafness in three South American families

Background: Corneal Dystrophy and Perceptive Deafness (CDPD) or Harboyan syndrome is an autosomal recessive rare disorder, characterized by congenital corneal opacities and progressive sensorineural hearing loss, which usually begins after the second decades of life. This study reports the ophthalmic, audiological and genetic features, in five CDPD affected patients from three Chilean families.

Materials and Methods: Five individuals affected with CDPD from three unrelated Chilean families were clinically and genetically examined. To evaluate a putative founder mutation 7 SNPs were analyzed in the three families, an Argentinian patient (carrier of the same mutation previously reported) and 87 Chilean controls.

Results: The ophthalmic symptoms in the five patients were bilateral and symmetric, starting before one year of age, and visual acuity varied from 0.1 to 0.3. In all cases, hearing loss began over 8 years old. The sequence of the 19 exons of SLC4A11 gene of all the affected patients exhibited homozygous eight nucleotide sequence duplication (c.2233_2240dup TATGACAC, p.(Ile748Metfs*5)) at the end of exon 16. All the affected patients of the three families were homozygous for a haplotype composed of five SNPs and covering 4,1 Mb. The same haplotype was present in one allele of the heterozygous Argentinean patient and has a frequency of 2.76% in Chilean population.

Conclusions: The five CDPD patients were homozygous for the same mutation in the SLC4A11 gene. Haplotype analysis of all the affected, including the case reported from Argentina was in accordance with a founder mutation.