Nonlinear cascades of surface oceanic geostrophic kinetic energy in the frequency domain

Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/111877/1/jpo_frequencycascades_2012.pd

Cognitive deficits following exposure to pneumococcal meningitis: an event-related potential study

<p>Abstract</p> <p>Background</p> <p>Pneumococcal meningitis (PM) is a severe and life-threatening disease that is associated with cognitive impairment including learning difficulties, cognitive slowness, short-term memory deficits and poor academic performance. There are limited data on cognitive outcomes following exposure to PM from Africa mainly due to lack of culturally appropriate tools. We report cognitive processes of exposed children as measured by auditory and visual event-related potentials.</p> <p>Methods</p> <p>Sixty-five children (32 male, mean 8.4 years, SD 3.0 years) aged between 4-15 years with a history of PM and an age-matched control group of 93 children (46 male; mean 8.4 years, SD 2.7 years) were recruited from a well-demarcated study area in Kilifi. In the present study, both baseline to peak and peak-to-peak amplitude differences are reported.</p> <p>Results</p> <p>Children with a history of pneumococcal meningitis had significantly longer auditory P1 and P3a latencies and smaller P1 amplitudes compared to unexposed children. In the visual paradigm, children with PM seemingly lacked a novelty P3a component around 350 ms where control children had a maximum, and showed a lack of stimulus differentiation at Nc. Further, children with exposure to PM had smaller peak to peak amplitude (N2-P1) compared to unexposed children.</p> <p>Conclusion</p> <p>The results suggest that children with a history of PM process novelty differently than do unexposed children, with slower latencies and reduced or absent components. This pattern suggests poorer auditory attention and/or cognitive slowness and poorer visual attention orienting, possibly due to disruption in the functions of the lateral prefrontal and superior temporal cortices. ERPs may be useful for assessment of the development of perceptual-cognitive functions in post brain-injury in African children by providing an alternate way of assessing cognitive development in patient groups for whom more typical standardized neuropsychological assessments are unavailable.</p

Decorticate, decerebrate and opisthotonic posturing and seizures in Kenyan children with cerebral malaria

BACKGROUND: Abnormal motor posturing is often observed in children with cerebral malaria, but the aetiology and pathogenesis is poorly understood. This study examined the risk factors and outcome of posturing in Kenyan children with cerebral malaria. METHODS: Records of children admitted to Kilifi district hospital with cerebral malaria from January, 1999 through December, 2001 were reviewed for posturing occurring on or after admission. The clinical characteristics, features of raised intracranial pressure, number of seizures and biochemical changes in patients that developed posturing was compared to patients who did not. RESULTS: Of the 417 children with complete records, 163 (39.1%) had posturing: 85 on admission and 78 after admission to hospital. Decorticate posturing occurred in 80, decerebrate in 61 and opisthotonic posturing in 22 patients. Posturing was associated with age ≥ 3 years (48.1 vs 35.8%, p = 0.01) and features of raised intracranial pressure on funduscopy (adjusted OR 2.1 95%CI 1.2–3.7, p = 0.009) but not other markers of severity of disease. Unlike decorticate posturing, decerebrate (adjusted OR 1.9 95%CI 1.0–3.5) and opisthotonic posturing (adjusted OR 2.9 95%CI 1.0–8.1) were, in addition, independently associated with recurrence of seizures after admission. Opisthotonus was also associated with severe metabolic acidosis (OR 4.2 95%CI 3.2–5.6, p < 0.001). Thirty one patients with posturing died. Of these, 19 (61.3%) had features suggestive of transtentorial herniation. Mortality and neurological deficits on discharge were greatest in those developing posturing after admission. CONCLUSION: Abnormal motor posturing is a common feature of cerebral malaria in children. It is associated with features of raised intracranial pressure and recurrence of seizures, although intracranial hypertension may be the primary cause

P2X receptors: epithelial ion channels and regulators of salt and water transport.

When the results from electrophysiological studies of renal epithelial cells are combined with data from in vivo tubule microperfusion experiments and immunohistochemical surveys of the nephron, the accumulated evidence suggests that ATP-gated ion channels, P2X receptors, play a specialized role in the regulation of ion and water movement across the renal tubule and are integral to electrolyte and fluid homeostasis. In this short review, we discuss the concept of P2X receptors as regulators of salt and water salvage pathways, as well as acknowledging their accepted role as ATP-gated ion channels

Factors influencing quality of life following lower limb amputation for peripheral arterial occlusive disease: a systematic review of the literature

Background: The majority of lower limb amputations are undertaken in people with peripheral arterial occlusive disease,\ud and approximately 50% have diabetes. Quality of life is an important outcome in lower limb amputations; little is known\ud about what influences it, and therefore how to improve it.\ud Objectives: The aim of this systematic review was to identify the factors that influence quality of life after lower limb\ud amputation for peripheral arterial occlusive disease.\ud Methods: MEDLINE, EMBASE, CINAHL, PsycINFO, Web of Science and Cochrane databases were searched to identify\ud articles that quantitatively measured quality of life in those with a lower limb amputation for peripheral arterial occlusive\ud disease. Articles were quality assessed by two assessors, evidence tables summarised each article and a narrative\ud synthesis was performed.\ud Study design: Systematic review.\ud Results: Twelve articles were included. Study designs and outcome measures used varied. Quality assessment scores\ud ranged from 36% to 92%. The ability to walk successfully with a prosthesis had the greatest positive impact on quality\ud of life. A trans-femoral amputation was negatively associated with quality of life due to increased difficulty in walking\ud with a prosthesis. Other factors such as older age, being male, longer time since amputation, level of social support and\ud presence of diabetes also negatively affected quality of life.\ud Conclusion: Being able to walk with a prosthesis is of primary importance to improve quality of life for people with lower\ud limb amputation due to peripheral arterial occlusive disease. To further understand and improve the quality of life of this\ud population, there is a need for more prospective longitudinal studies, with a standardised outcome measure

Gain and Loss Learning Differentially Contribute to Life Financial Outcomes

Emerging findings imply that distinct neurobehavioral systems process gains and losses. This study investigated whether individual differences in gain learning and loss learning might contribute to different life financial outcomes (i.e., assets versus debt). In a community sample of healthy adults (n = 75), rapid learners had smaller debt-to-asset ratios overall. More specific analyses, however, revealed that those who learned rapidly about gains had more assets, while those who learned rapidly about losses had less debt. These distinct associations remained strong even after controlling for potential cognitive (e.g., intelligence, memory, and risk preferences) and socioeconomic (e.g., age, sex, ethnicity, income, education) confounds. Self-reported measures of assets and debt were additionally validated with credit report data in a subset of subjects. These findings support the notion that different gain and loss learning systems may exert a cumulative influence on distinct life financial outcomes

Characterization of Shewanella oneidensis MtrC: a cell-surface decaheme cytochrome involved in respiratory electron transport to extracellular electron acceptors

MtrC is a decaheme c-type cytochrome associated with the outer cell membrane of Fe(III)-respiring species of the Shewanella genus. It is proposed to play a role in anaerobic respiration by mediating electron transfer to extracellular mineral oxides that can serve as terminal electron acceptors. The present work presents the first spectropotentiometric and voltammetric characterization of MtrC, using protein purified from Shewanella oneidensis MR-1. Potentiometric titrations, monitored by UV–vis absorption and electron paramagnetic resonance (EPR) spectroscopy, reveal that the hemes within MtrC titrate over a broad potential range spanning between approximately +100 and approximately -500 mV (vs. the standard hydrogen electrode). Across this potential window the UV–vis absorption spectra are characteristic of low-spin c-type hemes and the EPR spectra reveal broad, complex features that suggest the presence of magnetically spin-coupled low-spin c-hemes. Non-catalytic protein film voltammetry of MtrC demonstrates reversible electrochemistry over a potential window similar to that disclosed spectroscopically. The voltammetry also allows definition of kinetic properties of MtrC in direct electron exchange with a solid electrode surface and during reduction of a model Fe(III) substrate. Taken together, the data provide quantitative information on the potential domain in which MtrC can operate

Ovine pedomics : the first study of the ovine foot 16S rRNA-based microbiome

We report the first study of the bacterial microbiome of ovine interdigital skin based on 16S rRNA by pyrosequencing and conventional cloning with Sanger-sequencing. Three flocks were selected, one a flock with no signs of footrot or interdigital dermatitis, a second flock with interdigital dermatitis alone and a third flock with both interdigital dermatitis and footrot. The sheep were classified as having either healthy interdigital skin (H), interdigital dermatitis (ID) or virulent footrot (VFR). The ovine interdigital skin bacterial community varied significantly by flock and clinical condition. The diversity and richness of operational taxonomic units was greater in tissue from sheep with ID than H or VFR affected sheep. Actinobacteria, Bacteriodetes, Firmicutes and Proteobacteria were the most abundant phyla comprising 25 genera. Peptostreptococcus, Corynebacterium and Staphylococcus were associated with H, ID and VFR respectively. Sequences of Dichelobacter nodosus, the causal agent of ovine footrot, were not amplified due to mismatches in the 16S rRNA universal forward primer (27F). A specific real time PCR assay was used to demonstrate the presence of D. nodosus which was detected in all samples including the flock with no signs of ID or VFR. Sheep with ID had significantly higher numbers of D. nodosus (104-109 cells/g tissue) than those with H or VFR feet

Comparison of embedded and added motor imagery training in patients after stroke: Study protocol of a randomised controlled pilot trial using a mixed methods approach

Copyright @ 2009 Schuster et al; licensee BioMed Central Ltd. This is an Open Access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/2.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.Background: Two different approaches have been adopted when applying motor imagery (MI) to stroke patients. MI can be conducted either added to conventional physiotherapy or integrated within therapy sessions. The proposed study aims to compare the efficacy of embedded MI to an added MI intervention. Evidence from pilot studies reported in the literature suggests that both approaches can improve performance of a complex motor skill involving whole body movements, however, it remains to be demonstrated, which is the more effective one.Methods/Design: A single blinded, randomised controlled trial (RCT) with a pre-post intervention design will be carried out. The study design includes two experimental groups and a control group (CG). Both experimental groups (EG1, EG2) will receive physical practice of a clinical relevant motor task ('Going down, laying on the floor, and getting up again') over a two week intervention period: EG1 with embedded MI training, EG2 with MI training added after physiotherapy. The CG will receive standard physiotherapy intervention and an additional control intervention not related to MI.The primary study outcome is the time difference to perform the task from pre to post-intervention. Secondary outcomes include level of help needed, stages of motor task completion, degree of motor impairment, balance ability, fear of falling measure, motivation score, and motor imagery ability score. Four data collection points are proposed: twice during baseline phase, once following the intervention period, and once after a two week follow up. A nested qualitative part should add an important insight into patients' experience and attitudes towards MI. Semi-structured interviews of six to ten patients, who participate in the RCT, will be conducted to investigate patients' previous experience with MI and their expectations towards the MI intervention in the study. Patients will be interviewed prior and after the intervention period.Discussion: Results will determine whether embedded MI is superior to added MI. Findings of the semi-structured interviews will help to integrate patient's expectations of MI interventions in the design of research studies to improve practical applicability using MI as an adjunct therapy technique

Lectin-like bacteriocins from pseudomonas spp. utilise D-rhamnose containing lipopolysaccharide as a cellular receptor

Lectin-like bacteriocins consist of tandem monocot mannose-binding domains and display a genus-specific killing activity. Here we show that pyocin L1, a novel member of this family from Pseudomonas aeruginosa, targets susceptible strains of this species through recognition of the common polysaccharide antigen (CPA) of P. aeruginosa lipopolysaccharide that is predominantly a homopolymer of d-rhamnose. Structural and biophysical analyses show that recognition of CPA occurs through the C-terminal carbohydrate-binding domain of pyocin L1 and that this interaction is a prerequisite for bactericidal activity. Further to this, we show that the previously described lectin-like bacteriocin putidacin L1 shows a similar carbohydrate-binding specificity, indicating that oligosaccharides containing d-rhamnose and not d-mannose, as was previously thought, are the physiologically relevant ligands for this group of bacteriocins. The widespread inclusion of d-rhamnose in the lipopolysaccharide of members of the genus Pseudomonas explains the unusual genus-specific activity of the lectin-like bacteriocins