368 research outputs found
Impact of Sugar Substitutes on Glucose Control in Diabetic Patients
Objective: To evaluate the impact of nonnutritive sugar substitutes on glycemic control in patients with diabetes. Data Sources: A comprehensive review of the literature was conducted in PubMed (1966-March 2012) and Scopus. A combination of MeSH terms and keywords were used, including acesulfame, aspartame, diabetes, neotame, rebiana, saccharin, stevia, and sucralose. Study Selection and Data Extraction: Clinical studies evaluating the impact of nonnutritive sweeteners on measures of diabetic control, including, but not limited to, blood glucose levels, postprandial blood glucose, and hemoglobin A1c were selected for review. Searches were limited to only nonnutritive sweeteners available in the US. Data Synthesis: Nine clinical trials that evaluated nonnutritive sweeteners in a total of 490 patients with diabetes were found. Doses of sweeteners in the studies varied from below acceptable daily intake levels for 3 consecutive days to daily dosing for up to 18 weeks and up to 3.5 times the acceptable daily intake levels. No significant differences in overall effects on glycemic control and insulin response were found. Conclusions: Nonnutritive sweeteners do not appear to affect glycemic control in patients with diabetes. Patients should be counseled to maintain an appropriate energy balance in their diet, with or without the use of nonnutritive sweeteners
Bowhead and Gray Whale Distributions, Sighting Rates, and Habitat Associations in the Eastern Chukchi Sea, Summer and Fall 2009â15, with a Retrospective Comparison to 1982â91
We analyzed data from line-transect aerial surveys for marine mammals conducted in the eastern Chukchi Sea (67Ëâ72Ë N, 157Ëâ169Ë W) in July to October of 2009â15 to investigate bowhead and gray whale distributions, behaviors, sighting rates, and habitat selection preferences, the last of which allowed direct comparison with results from data collected in this area in 1982â91. Bowhead whales use the eastern Chukchi Sea primarily for migrating between the Beaufort Sea and the Bering Sea, while gray whales use the area to feed on locally abundant benthic amphipods and other prey. Bowhead whales were observed during all survey months and were distributed up to 300 km offshore west and southwest of Point Barrow, Alaska, but without a defined migratory corridor in either summer (July-August) or fall (September-October). Bowhead whale sighting rates (whales per km on effort) were highest in the shelf/trough (51â200 m North) depth zone in the northeastern Chukchi Sea in both summer and fall. This pattern was reflected in habitat selection ratios, which found bowhead whales in summer and fall selecting primarily shelf/trough habitat in the northeastern Chukchi Sea, with shelf habitat (36 â 50 m) being preferred secondarily. Gray whales were observed in all survey months and were distributed primarily within ~95 km of shore between Point Barrow and Icy Cape in the northeastern Chukchi Sea, and about 60â115 km southwest of Point Hope in the southern Chukchi Sea. In both summer and fall, gray whale sighting rates and habitat selection ratios were highest in the shelf/trough (51â200 m South) depth zone in the southern Chukchi Sea. In the northeastern part of the study area, gray whale sighting rates and habitat selection ratios both identified coastal habitat (†35 m) as preferred habitat in summer and shelf/trough (51â200 m North) as preferred habitat in fall. Distribution and habitat associations of bowhead and gray whales remained similar over the 34-year time span with one exception: gray whale preference for shelf/trough habitat in the southern Chukchi Sea is now evident throughout summer and fall, whereas three decades ago gray whale preference for that area was limited to fall only.Nous avons analysĂ© les donnĂ©es provenant de levĂ©s aĂ©riens par transects linĂ©aires Ă lâĂ©gard de mammifĂšres marins, levĂ©s effectuĂ©s dans lâest de la mer des Tchouktches (67Ëâ72Ë N, 157Ëâ169Ë O) dâoctobre Ă juillet 2009 Ă 2015 afin de prĂ©lever des donnĂ©es sur la rĂ©partition des baleines borĂ©ales et des baleines grises, sur leurs comportements, sur leurs taux dâobservation et sur leurs prĂ©fĂ©rences en matiĂšre dâhabitat. Ce dernier Ă©lĂ©ment nous a permis de faire des comparaisons directes avec les rĂ©sultats de la collecte de donnĂ©es effectuĂ©e dans cette rĂ©gion entre 1982 et 1991. Les baleines borĂ©ales se servent principalement de lâest de la mer des Tchouktches pour migrer entre la mer de Beaufort et la mer de BĂ©ring, tandis que les baleines grises empruntent cette rĂ©gion pour se nourrir des amphipodes benthiques qui y abondent ainsi que dâautres proies. Des baleines borĂ©ales ont Ă©tĂ© observĂ©es pendant tous les mois visĂ©s par les levĂ©s, et celles-ci Ă©taient rĂ©parties sur une distance allant jusquâĂ 300 km au large, Ă lâouest et au sud-ouest de Point Barrow, en Alaska, sans toutefois emprunter un couloir migratoire particulier Ă lâĂ©tĂ© (juillet et aoĂ»t) ou Ă lâautomne (septembre et octobre). Les taux dâobservation de baleines borĂ©ales (nombre de baleines par km Ă lâeffort) Ă©taient plus Ă©levĂ©s dans la zone de profondeur de plateformes et de dĂ©pressions (de 51 Ă 200 m nord) faisant partie du nord-est de la mer des Tchouktches, tant Ă lâĂ©tĂ© quâĂ lâautomne. Cette tendance se reflĂšte dans les rapports de sĂ©lection dâhabitats, selon lesquels les baleines borĂ©ales choisissent principalement, lâĂ©tĂ© et lâautomne, un habitat de plateformes et de dĂ©pressions dans le nord-est de la mer des Tchouktches, lâhabitat des plateformes (de 36 Ă 50 m) constituant une prĂ©fĂ©rence secondaire. Des baleines grises ont Ă©tĂ© observĂ©es pendant tous les mois visĂ©s par les levĂ©s. Elles se rĂ©partissaient principalement Ă lâintĂ©rieur de ~95 km de la cĂŽte, entre Point Barrow et Icy Cape, dans le nord-est de la mer des Tchouktches, et Ă environ 60 Ă 115 km au sud-ouest de Point Hope, dans le sud de la mer des Tchouktches. Tant Ă lâĂ©tĂ© quâĂ lâautomne, les taux dâobservation et les rapports de sĂ©lection dâhabitats des baleines grises Ă©taient Ă leur point le plus Ă©levĂ© dans la zone de profondeur des plateformes et des dĂ©pressions (de 51 Ă 200 m sud) du sud de la mer des Tchouktches. Dans le secteur nord-est de la rĂ©gion visĂ©e par lâĂ©tude, les taux dâobservation et les ratios de sĂ©lection dâhabitats des baleines grises ont tous deux permis dâaffirmer que lâhabitat cĂŽtier (†35 m) Ă©tait lâhabitat prĂ©fĂ©rĂ© pendant lâĂ©tĂ©, et que lâhabitat des plateformes et des dĂ©pressions (de 51 Ă 200 m nord) Ă©tait lâhabitat prĂ©fĂ©rĂ© Ă lâautomne. Les associations en matiĂšre de rĂ©partition et dâhabitat des baleines borĂ©ales et des baleines grises sont demeurĂ©es semblables au cours de la pĂ©riode de 34 ans, Ă une exception prĂšs : la prĂ©fĂ©rence de la baleine grise pour lâhabitat des plateformes et des dĂ©pressions dans le sud de la mer des Tchouktches est maintenant Ă©vidente Ă lâĂ©tĂ© et Ă lâautomne, tandis quâil y a trois dĂ©cennies, la prĂ©fĂ©rence de la baleine grise pour cet habitat se limitait Ă lâautomne
Bowhead and Beluga Whale Distributions, Sighting Rates, and Habitat Associations in the Western Beaufort Sea in Summer and Fall 2009â16, with Comparison to 1982â91
We analyzed data from line-transect aerial surveys for marine mammals conducted in the western Beaufort Sea (shore to 72Ë N, 140Ëâ157Ë W) from July to October of 2009â16 to investigate the distribution, behaviors, sighting rates, and habitat use preferences of bowhead and beluga whales. The habitat use data allowed for direct comparison with data collected in the same area from 1982 to 1991. Both species are ice-adapted, migrating through leads in sea ice in spring, and are seasonal inhabitants of the western Beaufort Sea during summer and fall. From 2009 to 2016, bowheads were seen in all survey months, with the highest overall sighting rate (whales per km) in August. Bowhead sighting rates were highest in the whalesâ preferred habitats: outer shelf habitat (51â200 m depth) in July and inner shelf-shallow habitat (†20 m depth) in August, September, and October. Beluga whales were also seen in all survey months, with highest overall sighting rate in July. Beluga whales were overwhelmingly associated with continental slope habitat (201â2000 m depth) in all months. Bowhead distribution and depth preferences in summer months of 2009â16 differed from those observed in 1982â91, when bowheads were not seen during limited survey effort in July and preferred outer continental shelf habitat in August. These differences indicate that bowhead whale preference for shallow shelf habitat now occurs earlier in summer than it used to. Beluga distribution and depth preference remained similar between 1982â91 and 2009â16, with strong preference for continental slope during both periods. Differences in sea ice cover habitat association for both species are likely due more to the relative lack of sea ice in recent years compared to the earlier period than to shifts in habitat preference. Habitat partitioning between bowhead and beluga whales in the western Beaufort Sea remained evident except in July, when both species used continental slope habitat. In July â October 2009â16, the distribution, sighting rates, and behavior of both bowheads and belugas in the western Beaufort showed considerable interannual variation, which underscores the importance of annual sampling to accurate records of the complex western Beaufort Sea ecosystem.Nous avons analysĂ© les donnĂ©es dĂ©coulant de levĂ©s aĂ©riens de transects linĂ©aires pour mammifĂšres marins, levĂ©s effectuĂ©s dans lâouest de la mer de Beaufort (de la rive jusquâĂ 72Ë N, et de 140Ë jusquâĂ 157Ë O) de juillet Ă octobre 2009 Ă 2016. Ces levĂ©s avaient pour but dâĂ©tudier la distribution, les comportements, les taux dâobservation ainsi que les prĂ©fĂ©rences dâutilisation de lâhabitat des baleines borĂ©ales et des bĂ©lugas. Les donnĂ©es relatives Ă lâutilisation de lâhabitat ont permis dâĂ©tablir des comparaisons directes avec les donnĂ©es recueillies dans le mĂȘme secteur de 1982 Ă 1991. Ces deux espĂšces sont adaptĂ©es Ă la glace, migrent par des chenaux formĂ©s dans la glace de mer au printemps et sont des habitants saisonniers de lâouest de la mer de Beaufort pendant lâĂ©tĂ© et lâautomne. Entre 2009 et 2016, des baleines borĂ©ales ont Ă©tĂ© aperçues pendant tous les mois visĂ©s par les levĂ©s, le taux dâobservation gĂ©nĂ©ral le plus Ă©levĂ© (nombre de baleines par km) ayant Ă©tĂ© enregistrĂ© au mois dâaoĂ»t. Les taux dâobservation des baleines borĂ©ales Ă©taient les plus Ă©levĂ©s dans les habitats prĂ©fĂ©rĂ©s de ces baleines, soit lâhabitat de la plateforme externe (de 51 m Ă 200 m de profondeur) en juillet et lâhabitat de la plateforme interne peu profonde (†20 m de profondeur) en aoĂ»t, en septembre et en octobre. Des bĂ©lugas ont Ă©galement Ă©tĂ© aperçus pendant tous les mois visĂ©s par les levĂ©s, le taux dâobservation gĂ©nĂ©ral le plus Ă©levĂ© ayant Ă©tĂ© enregistrĂ© en juillet. Les bĂ©lugas Ă©taient massivement associĂ©s Ă lâhabitat de la pente continentale (de 201 m Ă 2 000 m de profondeur) pendant tous les mois. La distribution et les prĂ©fĂ©rences de profondeur des baleines borĂ©ales pendant les mois dâĂ©tĂ© 2009 Ă 2016 diffĂ©raient de celles observĂ©es de 1982 Ă 1991, lorsque les baleines borĂ©ales nâont pas Ă©tĂ© aperçues dans le cadre des quelques levĂ©s qui ont Ă©tĂ© effectuĂ©s en juillet et prĂ©fĂ©raient leur habitat de la plateforme continentale externe en aoĂ»t. Ces diffĂ©rences indiquent que la prĂ©fĂ©rence des baleines borĂ©ales pour lâhabitat de la plateforme peu profonde se manifeste maintenant plus tĂŽt lâĂ©tĂ© quâauparavant. De 1982 Ă 1991 et de 2009 Ă 2016, la distribution des bĂ©lugas et leur prĂ©fĂ©rence de profondeur sont restĂ©es semblables, avec une prĂ©fĂ©rence marquĂ©e pour la pente continentale pendant les deux pĂ©riodes. Pour les deux espĂšces, les diffĂ©rences sur le plan de lâassociation de la couverture de glace marine sont vraisemblablement davantage attribuables au manque relatif de glace de mer ces derniĂšres annĂ©es comparativement Ă la pĂ©riode prĂ©cĂ©dente plutĂŽt quâĂ une variation de la prĂ©fĂ©rence de lâhabitat. Dans lâouest de la mer de Beaufort, la sĂ©paration de lâhabitat entre les baleines borĂ©ales et les bĂ©lugas demeurait Ă©vidente, sauf en juillet, quand les deux espĂšces utilisaient lâhabitat de la pente continentale. De juillet Ă octobre 2009 Ă 2016, la distribution, les taux dâobservation et le comportement des baleines borĂ©ales et des bĂ©lugas dans lâouest de la mer de Beaufort ont affichĂ© une variation considĂ©rable dâune annĂ©e Ă lâautre, ce qui fait ressortir lâimportance de faire des Ă©chantillonnages annuels afin dâobtenir des donnĂ©es prĂ©cises au sujet de lâĂ©cosystĂšme complexe de lâouest de la mer de Beaufort
Patient perceptions of oral health care following stroke : a qualitative study
Background: Stroke is a serious cerebrovascular disease and is one of the worldâs leading causes of disability. Maintaining good oral health is a challenge among those hospitalised after stroke. A multidisciplinary approach to oral care involving non-dental professionals can be beneficial in improving oral health outcomes for patients. The aim of this study was to understand the perceptions of stroke survivors regarding oral healthcare across acute and rehabilitation settings. Methods: A descriptive qualitative approach was used. Face-to-face semi-structured interviews were conducted. A framework analysis was employed to analyse the data. Patients who had recently experienced a stroke were purposively recruited across both acute and rehabilitation settings, at two metropolitan hospitals in Sydney, Australia. In total, 11 patients were interviewed. Results: Although participants recognised the importance of oral health, few understood the link between oral and general health. Regular oral hygiene practices varied since having stroke, with a few receiving oral care assistance from nurses. Time, cost and lack of information were some barriers to accessing dental services, while supportive measures such as coordination of oral care, financial subsidy and nurse assistance were strategies proposed to support oral care practices amongst stroke survivors. Conclusions: There is scope to improve current models of oral care in stroke. While stroke survivors understand the importance of oral care, an integrated oral health model with a multidisciplinary approach could improve health outcomes
Developmental stage of oligodendrocytes determines their response to activated microglia in vitro
<p>Abstract</p> <p>Background</p> <p>Oligodendrocyte progenitor cells (OPCs) and mature oligodendrocytes are both lost in central nervous system injury and disease. Activated microglia may play a role in OPC and oligodendrocyte loss or replacement, but it is not clear how the responses of OPCs and oligodendrocytes to activated microglia differ.</p> <p>Methods</p> <p>OPCs and microglia were isolated from rat cortex. OPCs were induced to differentiate into oligodendrocytes with thyroid hormone in defined medium. For selected experiments, microglia were added to OPC or oligodendrocyte cultures. Lipopolysaccharide was used to activate microglia and microglial activation was confirmed by TNFα ELISA. Cell survival was assessed with immunocytochemistry and cell counts. OPC proliferation and oligodendrocyte apoptosis were also assessed.</p> <p>Results</p> <p>OPCs and oligodendrocytes displayed phenotypes representative of immature and mature oligodendrocytes, respectively. Activated microglia reduced OPC survival, but increased survival and reduced apoptosis of mature oligodendrocytes. Activated microglia also underwent cell death themselves.</p> <p>Conclusion</p> <p>Activated microglia may have divergent effects on OPCs and mature oligodendrocytes, reducing OPC survival and increasing mature oligodendrocyte survival. This may be of importance because activated microglia are present in several disease states where both OPCs and mature oligodendrocytes are also reacting to injury. Activated microglia may simultaneously have deleterious and helpful effects on different cells after central nervous system injury.</p
Exercising Caution Upon WakingâCan Exercise Reduce Sleep Inertia?
Sleep inertia, the transitional state of reduced alertness and impaired cognitive performance upon waking, is a safety risk for on-call personnel who can be required to perform critical tasks soon after waking. Sleep inertia countermeasures have previously been investigated; however, none have successfully dissipated sleep inertia within the first 15 min following waking. During this time, on-call personnel could already be driving, providing advice, or performing other safety-critical tasks. Exercise has not yet been investigated as a sleep inertia countermeasure but has the potential to stimulate the key physiological mechanisms that occur upon waking, including changes in cerebral blood flow, the cortisol awakening response, and increases in core body temperature. Here, we examine these physiological processes and hypothesize how exercise can stimulate them, positioning exercise as an effective sleep inertia countermeasure. We then propose key considerations for research investigating the efficacy of exercise as a sleep inertia countermeasure, including the need to determine the intensity and duration of exercise required to reduce sleep inertia, as well as testing the effectiveness of exercise across a range of conditions in which the severity of sleep inertia may vary. Finally, practical considerations are identified, including the recommendation that qualitative field-based research be conducted with on-call personnel to determine the potential constraints in utilizing exercise as a sleep inertia countermeasure in real-world scenarios
Exercising Caution Upon WakingâCan Exercise Reduce Sleep Inertia?
Sleep inertia, the transitional state of reduced alertness and impaired cognitive performance upon waking, is a safety risk for on-call personnel who can be required to perform critical tasks soon after waking. Sleep inertia countermeasures have previously been investigated; however, none have successfully dissipated sleep inertia within the first 15 min following waking. During this time, on-call personnel could already be driving, providing advice, or performing other safety-critical tasks. Exercise has not yet been investigated as a sleep inertia countermeasure but has the potential to stimulate the key physiological mechanisms that occur upon waking, including changes in cerebral blood flow, the cortisol awakening response, and increases in core body temperature. Here, we examine these physiological processes and hypothesize how exercise can stimulate them, positioning exercise as an effective sleep inertia countermeasure. We then propose key considerations for research investigating the efficacy of exercise as a sleep inertia countermeasure, including the need to determine the intensity and duration of exercise required to reduce sleep inertia, as well as testing the effectiveness of exercise across a range of conditions in which the severity of sleep inertia may vary. Finally, practical considerations are identified, including the recommendation that qualitative field-based research be conducted with on-call personnel to determine the potential constraints in utilizing exercise as a sleep inertia countermeasure in real-world scenarios
Tumor Necrosis Factor Alpha Mediates GABAA Receptor Trafficking to the Plasma Membrane of Spinal Cord Neurons In Vivo
The proinflammatory cytokine TNFα contributes to cell death in central nervous system (CNS) disorders by altering synaptic neurotransmission. TNFα contributes to excitotoxicity by increasing GluA2-lacking AMPA receptor (AMPAR) trafficking to the neuronal plasma membrane. In vitro, increased AMPAR on the neuronal surface after TNFα exposure is associated with a rapid internalization of GABAA receptors (GABAARs), suggesting complex timing and dose dependency of the CNS's response to TNFα. However, the effect of TNFα on GABAAR trafficking in vivo remains unclear. We assessed the effect of TNFα nanoinjection on rapid GABAAR changes in rats (N = 30) using subcellular fractionation, quantitative western blotting, and confocal microscopy. GABAAR protein levels in membrane fractions of TNFα and vehicle-treated subjects were not significantly different by Western Blot, yet high-resolution quantitative confocal imaging revealed that TNFα induces GABAAR trafficking to synapses in a dose-dependent manner by 60âmin. TNFα-mediated GABAAR trafficking represents a novel target for CNS excitotoxicity
Physician-Confirmed and Administrative Definitions of Stroke in UK Biobank Reflect the Same Underlying Genetic Trait
BACKGROUND: Stroke in UK Biobank (UKB) is ascertained via linkages to coded administrative datasets and self-report. We studied the accuracy of these codes using genetic validation. METHODS: We compiled stroke-specific and broad cerebrovascular disease (CVD) code lists (Read V2/V3, ICD-9/-10) for medical settings (hospital, death record, primary care) and self-report. Among 408,210 UKB participants, we identified all with a relevant code, creating 12 stroke definitions based on the code type and source. We performed genome-wide association studies (GWASs) for each definition, comparing summary results against the largest published stroke GWAS (MEGASTROKE), assessing genetic correlations, and replicating 32 stroke-associated loci. RESULTS: The stroke case numbers identified varied widely from 3,976 (primary care stroke-specific codes) to 19,449 (all codes, all sources). All 12 UKB stroke definitions were significantly correlated with the MEGASTROKE summary GWAS results (rg.81-1) and each other (rg.4-1). However, Bonferroni-corrected confidence intervals were wide, suggesting limited precision of some results. Six previously reported stroke-associated loci were replicated using â„1 UKB stroke definition. CONCLUSIONS: Stroke case numbers in UKB depend on the code source and type used, with a 5-fold difference in the maximum case-sample size. All stroke definitions are significantly genetically correlated with the largest stroke GWAS to date
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