The Influence of Diabetic Peripheral Neuropathy on Local Postural Muscle and Central Sensory Feedback Balance Control

Poor balance control and increased fall risk have been reported in people with diabetic peripheral neuropathy (DPN). Traditional body sway measures are unable to describe underlying postural control mechanism. In the current study, we used stabilogram diffusion analysis to examine the mechanism under which balance is altered in DPN patients under local-control (postural muscle control) and central-control (postural control using sensory cueing). DPN patients and healthy age-matched adults over 55 years performed two 15-second Romberg balance trials. Center of gravity sway was measured using a motion tracker system based on wearable inertial sensors, and used to derive body sway and local/central control balance parameters. Eighteen DPN patients (age = 65.4±7.6 years; BMI = 29.3±5.3 kg/m²) and 18 age-matched healthy controls (age = 69.8±2.9; BMI = 27.0±4.1 kg/m²) with no major mobility disorder were recruited. The rate of sway within local-control was significantly higher in the DPN group by 49% (healthy local-control_slope = 1.23±1.06×10^-2 cm²/sec, P<0.01), which suggests a compromised local-control balance behavior in DPN patients. Unlike local-control, the rate of sway within central-control was 60% smaller in the DPN group (healthy central-control_slope-Log = 0.39±0.23, P<0.02), which suggests an adaptation mechanism to reduce the overall body sway in DPN patients. Interestingly, significant negative correlations were observed between central-control rate of sway with neuropathy severity (r _Pearson = 0.65-085, P<0.05) and the history of diabetes (r _Pearson = 0.58-071, P<0.05). Results suggest that in the lack of sensory feedback cueing, DPN participants were highly unstable compared to controls. However, as soon as they perceived the magnitude of sway using sensory feedback, they chose a high rigid postural control strategy, probably due to high concerns for fall, which may increase the energy cost during extended period of standing; the adaptation mechanism using sensory feedback depends on the level of neuropathy and the history of diabetes.     

A comparison between biochemical tests and the 'CAMP' reaction for identification of Aeromonas spp.

Aeromonas bacteria (110 strains) from a variety of clinical, food and environmental sources, were identified using routine biochemical tests. Concurrently they were tested aerobically and anaerobically for their ability to perform synergistic haemolysis with Staphylococcus aureus (the 'CAMP' reaction). Results did not support a reported observation that the 'CAMP' reaction can he used to facilitate speciation of Aeromonas bacteria.     

Mutant enzymes and tRNAs as probes of the glutaminyl-tRNA synthetase: tRNA(Gln) interaction.

This paper focuses on several aspects of the specificity of mutants of Escherichia coli glutaminyl-tRNA synthetase (GlnRS) and tRNA(Gln). Temperature-sensitive mutants located in glnS, the gene for GlnRS, have been described previously. The mutations responsible for the temperature-sensitive phenotype were analyzed, and pseudorevertants of these mutants isolated and characterized. The nature of these mutations is discussed in terms of their location in the three-dimensional structure of the tRNA(Gln).GlnRS complex. In order to characterize the specificity of the aminoacylation reaction, mutant tRNA(Gln) species were synthesized with either a 2'-deoxy AMP or 3'-deoxy AMP as their 3'-terminal nucleotide. Subsequent assays for aminoacylation and ATP/PPi exchange activity established the esterification of glutamine to the 2'-hydroxyl of the terminal adenosine; there is no glutaminylation of the 3'-OH group. This correlates with the classification of GlnRS as a class I aminoacyl-tRNA synthetase. Mutations in tRNA(Gln) are discussed which affect the recognition of GlnRS and the current concept of glutamine identity in E coli is reviewed.     

Targeting Homologous Recombination in Notch-Driven C. elegans Stem Cell and Human Tumors

Mammalian NOTCH1-4 receptors are all associated with human malignancy, although exact roles remain enigmatic. Here we employ glp-1(ar202), a temperature-sensitive gain-of-function C. elegans NOTCH mutant, to delineate NOTCH-driven tumor responses to radiotherapy. At ≤20°C, glp-1(ar202) is wild-type, whereas at 25°C it forms a germline stem cell⁄progenitor cell tumor reminiscent of human cancer. We identify a NOTCH tumor phenotype in which all tumor cells traffic rapidly to G2⁄M post-irradiation, attempt to repair DNA strand breaks exclusively via homology-driven repair, and when this fails die by mitotic death. Homology-driven repair inactivation is dramatically radiosensitizing. We show that these concepts translate directly to human cancer models.     

The Proverbial Bourdieu: Habitus and the Politics of Representation in the Ethnography of Kabylia

Since the 1970s, anthropologists have been centrally concerned with the relationship of ethnographic representation to political and historical context. Interestingly, the work of Pierre Bourdieu has largely escaped such contextualization, despite the significance of Bourdieu's ideas to anthropological theorizing. Today, many of Bourdieu's central concepts float free from the context out of which they arose—the Kabyle region of Algeria. This article addresses this omission by reading Bourdieu's early works against each other to reconstitute aspects of his methodology and fieldwork. Focusing on his choice to represent the Kabyles of his early work in prose, and those in his later work via proverbs, I suggest that key premises of Bourdieu's theory may not be supported by historical and ethnographic evidence. I consider how Bourdieu's position as a young social scientist grappling with ethnographic responsibilities in colonial wartime led him to privilege his interlocutors' accounts in some studies while expunging them from others. [Keywords: Bourdieu, represented speech, literacy, Algeria, Berbers]