Relationship between somatosensory function and the spinothalamocortical pathway in chronic stroke patients

Abstract

Diffusion tensor tractography (DTT) allows for identification and evaluation of the spinothalamic tract and its thalamocortical pathway (STP). We attempted to investigate the relationship between tactile sensation and the STP in chronic stroke patients. We measured fractional anisotropy, mean diffusivity, and tract volume of the STP. The tactile sensation score of the affected side in patients with preserved STP integrity was higher compared with that of patients with an interrupted STP. The remaining volume and integrity of the STP in the affected hemisphere were important factors for tactile sensation of the affected side in chronic patients with intracerebral hemorrhage (ICH).     

A Cysteine Endopeptidase (“Dionain”) Is Involved in the Digestive Fluid of Dionaea muscipula (Venus’s Fly-trap)

The carnivorous plant Dionaea muscipula (Venus’s flytrap) secretes proteinases into the digestive fluid to digest prey proteins. In this study, we obtained evidence that the digestive fluid contains a cysteine endopeptidase, presumably belonging to the papain family, through inhibitor studies and partial amino acid sequencing of the major SDS–PAGE band protein. The name “dionain” is proposed for the enzyme.     

The elm leaf beetle α-amylase and its activity relationship with insect feeding

The elm leaf beetle, Xanthogalerucella luteola (Coleoptera: Chrysomelidae) is the most serious pest of elm trees. This pest causes severe damage to elm trees during its growth stages and as a result, in the middle of summer, leaves become skeletised and start to fall down. In this work, biochemical characterisation of digestive α-amylase of this insect and its relationship with insect feeding was investigated. The insect gut was isolated and its α-amylase was extracted and starch (1%) was used as a substrate for the enzyme. Results showed that the enzyme’s optimum temperature and pH was 35?°C and 5.5, respectively. Some ions such as NaCl decreased the enzyme activity whilst MgCl₂ and CaCl₂ increased the enzyme activity. Gut content electrophoresis showed that only one α-amylase is active in this insect species. There was a correlation between the amount of leaf eaten by the insect and the amount of the enzyme activity.     

Tactile Detection Thresholds for a Single Asperity on an Otherwise Smooth Surface

An investigation was made of the capacities of humans to detect, by actively touching with the fingertip, the presence of a single, small asperity on a very smooth background. The asperity consisted of either a raised dot having a diameter of 602, 231, or 40 μum, or an edge, each etched into a silicon wafer using the methods of contact photolithography. The height of each dot or edge was varied and the subject was asked to make a forced choice on each test trial as to which of two wafers, one of which was blank, contained the asperity. The mean detection threshold, or minimal height of asperity corresponding to a d' of 1.35, was lowest for edges (0.85 ± 0.22 μm, SD) and increased with decreases in the diameter of dot from 1.09 ± 0.19 μm for a diameter of 602 μm to 2.94 ± 1.19 μm and 5.97 ± 2.02 μm for diameters of 231 μm and 40 μm, respectively. The type of skin displacement required for the detection of these small asperities was believed to be a local lateral deformation of the papillary ridges.     

Is low pathogenic avian influenza virus virulent for wild waterbirds?

Although low pathogenic avian influenza virus (LPAIV) is traditionally considered to have adapted to its wild waterbird host to become avirulent, recent studies have suggested that LPAIV infection might after all have clinical effects. Therefore, I reviewed the literature on LPAIV infections in wild waterbirds. The virulence of LPAIV was assessed in 17 studies on experimental infections and nine studies on natural infections. Reported evidence for virulence were reductions in return rate, feeding rate, body weight, long-range movement and reproductive success, as well as pathological changes in infected organs. However, major caveats in studies of experimental infections were unnatural route of LPAIV inoculation, animal husbandry not simulating natural stressors and low sensitivity of clinical assessment. Major caveats in studies of natural infections were incomplete measurement of LPAIV infection burden, quasi-experimental design and potential misclassification of birds. After taking these caveats into account, the only remaining evidence for virulence was that presence and intensity of LPAIV infection were negatively correlated with body weight. Based on this correlation, together with the demonstrated LPAIV tropism for the intestinal tract, I hypothesize that LPAIV reduces digestive tract function, and suggest how future studies could be directed to test this hypothesis.     

Benthic cyanobacterial bloom impacts the reefs of South Florida (Broward County, USA)

Benthic cyanobacteria of the genus Lyngbya can form prominent mats and blooms in tropical and subtropical coral reef and seagrass habitats worldwide. A Lyngbya bloom on the reef tract offshore of Broward County, Florida, was first noted in 2002, and although it is seasonally variable in its distribution and abundance, it has persisted and spread over the past 3 years. In this study, the most abundant species of Lyngbya found in the blooms have been identified and compared to other species of Lyngbya by morphological and molecular methods. The most common species of Lyngbya is consistent with the properties of Lyngbya confervoides C. Agardh. The 16S ribosomal DNA sequence shares 88–92% identity with other known Lyngbya sequences, suggesting that this bloom consists primarily of a new, previously unsequenced species of Lyngbya. The second most common Lyngbya in the bloom is consistent with Lyngbya polychroa. This persistent bloom is a concern because it smothers octocorals and other invertebrates and negatively impacts these southeastern Florida reefs.     

爪鲵消化系统的解剖学和组织学初步研究（图版Ⅵ，下）

本文报道了爪鲵消化系统的形态学和组织学结构特点。爪鲵口腔底部具有肌肉质的舌,食管很短,胃是呈纺锤形的长囊,胃壁较厚,粘膜厚,胃腺发达。消化管肌层皆为平滑肌,环肌明显多于纵肌。肝脏较大,分左、中、右三叶;有胆囊;胰腺长带状,胰管与胆管汇合后与小肠最前部的十二指肠相连。     

以儿童呼吸道感染为主的非典型EBV感染报道

目的报道儿童EBV感染所致的临床疾病谱与年龄特点,以进一步提高对EBV感染诊治水平.方法回顾性分析了EBV-VCA-IgM或EBV-DNA-PCR诊断的690例儿童EBV感染的疾病分布和年龄分布特点.结果EBV感染儿童非典型传染性单核细胞增多症患儿422例,占61.16%,非典型EBV感染268例,占38.84%.非典型EBV感染中以呼吸道感染最为多见,为191例,占非典型EBV感染的71.27%.其他为皮炎或口炎、血小板减少性紫癜、腹泻病、川畸病、肠系膜或颈淋巴结炎、肾炎或肾病和CNS感染等.EBV感染致传染性单核细胞增多症和呼吸道感染在各年龄组的分布差异无显著性,EBV感染男女比为1.79：1.结论儿童EBV感染所致疾病多样,累及系统多,非典型表现以呼吸道感染为主.传染性单核细胞增多症和呼吸道感染在各年龄组间差异无显著性.