Combined approach in bedside assessment of aspiration risk post stroke: PASS

BACKGROUND

Swallowing disorders are common and serious problems post stroke. Physical signs and ingestion test consist of main approaches of bedside screening of aspiration.

AIM

To assess the composability of these approaches.

DESIGN

A pilot study to develop a combined schema; secondly a validation study of this schema.

SETTING

Inpatient of Neurology Department and of Rehabilitation Department.

POPULATION

Forty-one patients post acute stroke included in the pilot study; 107 patients of subacute stroke for validation study.

METHODS

In pilot study, patients were assessed using Clinical Predicative Scale of Aspiration (CPSA) and 3-ounce Water swallow Test (3oz WT). Videofluoroscopic examination (VFSE) was performed as gold standard when the results of screening were discordant. In validation study, swallowing disorders were assessed systematically using CPSA, 3 oz WT and VFSE.

RESULTS

The combined screening schema, Practical Aspiration Screening Scheme (PASS), consisted of a 3oz WT to enhance results of the uncertain range of CPSA. Validation study showed that sensitivity and specificity of the 3oz WT were 87.3% and 42.3% respectively; those of CPSA were 50.1% and 50.0%, with a range of uncertainty in 42.6% of patients. The sensitivity of PASS was 89.1%, comparable to that of the 3oz WT, while the specificity of PASS was 80.8%, significantly higher than that of single tests. PASS also reduced systematic recourse to VFSE with a substantial agreement with it (kappa=0.7).

CONCLUSION

Physical signs and ingestion test are complementary in the screening of aspiration.

CLINICAL REHABILITATION IMPACT

Combined schema enhances the efficiency of bedside screening of aspiration.

Mimotopes of mutalysin-II from Lachesis muta snake venom induce hemorrhage inhibitory antibodies upon vaccination of rabbits

Mutalysin-II (mut-II) from Lachesis muta snake venom is an endopeptidase with hemorrhagic activity. A mAb against mutalysin-II that neutralized the hemorrhagic effect was produced previously. To identify the mAb epitopes, sets of 15-mer overlapping peptides covering the mut-II amino acid sequence were synthesized using the SPOT method and tested but failed to react with the mAb. Using a phage-display approach seventeen clones reactive with mAb were identified. Additional immunoassays with the peptides and mAb identified the QCTMDQGRLRCR, TCATDQGRLRCT, HCFHDQGRVRCA, HCTMDQGRLRCR and SCMLDQGRSRCR sequences as possible epitopes. Immunization of rabbits with these peptides induced antibodies that recognize mut-II and protected against the hemorrhagic effects of Lachesis venom.

Porous Organosilicates for On-Chip Dielectric Applications

Porous organosilicates useful for on-chip insulator applications can be prepared by templating the vitrification of low molecular weight silsesquioxanes (SSQs) using highly branched, thermally labile macromolecules which are subsequently removed in a thermal process to generate porosity. The process involves spin coating a mixture of the matrix material and the porogen (pore generator) followed by thermal curing to initiate vitrification and decomposition of the porogen. The morphology is fixed during the formation of the nanoscopic inorganicorganic hybrid and is maintained during foaming. This process generates controllable and stable morphologies where the void volume is determined by the porogen loading level. The porous materials are thermally robust and intrinsically hydrophobic without subsequent chemical treatment. Dielectric constants of < 2.2 are easily achieved for pore volumes of only 20%, and this porosity appears to be predominately closed cell in nature. These materials display a number of thermal mechanical and electric properties consistent with the requirements for on-chip insulator applications.

Existence of metastable kinetic modes

The nonlinear evolution of resonantly driven systems, such as suprathermal particle driven modes in magnetically confined plasmas, is shown to strongly depend on the existence and nature of an underlying damping mechanism. When background resonant damping is present, subcritical states can take place. In particular, purely nonlinear steady-state regimes are found, whose destabilization threshold and saturation levels are calculated and validated using numerical simulations. This nonlinear behavior can be of relevance for acoustic modes in magnetically confined plasmas.

Self- and clinician-rated Montgomery-Asberg Depression Rating Scale: evaluation in clinical practice

BACKGROUND

Time- and cost-effective self-rating scales of depressive symptoms are particularly valuable for frequent use in large-scale effectiveness trials. The aim of the present study was to examine the psychometric properties of the French version of the self-rated Montgomery-Asberg Depression Rating Scale (MADRS-S) and determine whether it might complement the MADRS in monitoring depression severity and change over time in routine clinical practice.

METHODS

Sixty-three adult outpatients with a current depressive episode completed the MADRS-S and were interviewed with the MADRS on two occasions, within a 1-month interval.

RESULTS

All patients readily accepted the MADRS-S. It showed good to excellent internal consistency (Cronbach's alpha 0.85 at Time 1; 0.94 at Time 2). Its factor structure revealed that a single component explained a large proportion of variability (47.0% at Time 1; 68.8% at Time 2). Concurrent validity of the self- and clinician-rated versions was good (Pearson's correlation coefficients for total scores 0.81 at Time 1; 0.91 at Time 2). The MADRS-S was sensitive to change over the 4-week observation period (correlation of 0.71 between change scores on self- and clinician-rated instruments).

LIMITATIONS

Generalizability is restricted to outpatients with moderate to severe depression, and the MADRS-S ability to measure treatment effects needs to be examined.

CONCLUSIONS

The present study indicates that the MADRS-S displays favourable psychometric properties and suggests that it might be a valid complement to the MADRS, both in research settings and clinical practice.

Vasoactive intestinal peptide ameliorates intestinal barrier disruption associated with Citrobacter rodentium-induced colitis

Attaching and effacing bacterial pathogens attach to the apical surface of epithelial cells and disrupt epithelial barrier function, increasing permeability and allowing luminal contents access to the underlying milieu. Previous in vitro studies demonstrated that the neuropeptide vasoactive intestinal peptide (VIP) regulates epithelial paracellular permeability, and the high concentrations and close proximity of VIP-containing nerve fibers to intestinal epithelial cells would support such a function in vivo. The aim of this study was to examine whether VIP treatment modulated Citrobacter rodentium-induced disruption of intestinal barrier integrity and to identify potential mechanisms of action. Administration of VIP had no effect on bacterial attachment although histopathological scoring demonstrated a VIP-induced amelioration of colitis-induced epithelial damage compared with controls. VIP treatment prevented the infection-induced increase in mannitol flux a measure of paracellular permeability, resulting in levels similar to control mice, and immunohistochemical studies demonstrated that VIP prevented the translocation of tight junction proteins: zonula occludens-1, occludin, and claudin-3. Enteropathogenic Escherichia coli (EPEC) infection of Caco-2 monolayers confirmed a protective role for VIP on epithelial barrier function. VIP prevented EPEC-induced increase in long myosin light chain kinase (MLCK) expression and myosin light chain phosphorylation (p-MLC). Furthermore, MLCK inhibition significantly attenuated bacterial-induced epithelial damage both in vivo and in vitro. In conclusion, our results indicate that VIP protects the colonic epithelial barrier by minimizing bacterial-induced redistribution of tight junction proteins in part through actions on MLCK and MLC phosphorylation.

Coalescence and splitting of confined droplets at microfluidic junctions

The ability to merge two droplets is an important component of droplet-based lab-on-a-chip devices, yet flow-induced coalescence is difficult to achieve due to long film drainage times compared with relatively short residence times. We examine droplet collisions at a simple microfluidic T-junction and characterize the response for a wide range of droplet sizes and speeds. We find that three primary responses occur, where coalescence occurs easily at low collision speeds, smaller droplets traveling faster slip past one another without coalescing, and larger and faster droplets can break one another into multiple segments. The critical capillary number for coalescence agrees well with previously reported scaling for isolated droplet pairs when local curvature and speed are taken into account. The critical capillary number for splitting of droplets agrees well with a previously reported stability condition for individual droplets stretching in an extensional flow. Quantifying the necessary conditions for coalescence and non-coalescence behavior should enable the informed design of lab on chip devices based on discrete liquid segments.

Redistribution of suprathermal electrons due to fishbone frequency jumps

MHD instabilities driven by fast electrons identified as fishbonelike modes have been detected on Tore Supra during lower hybrid current drive discharges. Direct experimental evidence is reported of a novel feature: the regular redistribution of suprathermal electrons toward external tokamak regions which are correlated to periodic mode frequency jumps. Sharp drops of the electron temperature time trace are factually linked to the cyclical deterioration of the fast electron confinement.