1,025 research outputs found
The effect of sepsis on cerebral microvascular blood flow
Background: Sepsis is a dysregulated host response to infection that affects 18 000 000 people worldwide, and over 325 000 000 dollars are spent treating sepsis in Canada every year. One of the symptoms of severe sepsis is an altered mental state, which is accompanied with a measured decrease in oxygen levels in the skeletal muscle microvasculature. It is hypothesized that his altered mental state is due to a lack of oxygenated blood reaching the brain.
Hypothesis: After the onset of sepsis, microvascular cerebral blood flow and oxygen levels in the blood will decrease. Onset of decreased blood flow in the brain is expected to occur later than in skeletal muscle.
Methods: Data will be collected rom Sprague Dawley rats. Rats will undergo a sepsis inducing procedure, and one of the right leg muscles will be exposed. Data will be collected from this muscle via intravital video microscopy, and from the left leg and the brain via near infrared spectroscopy.
Results: Expected results include a decrease in microvascular blood flow in both legs and the brain, with a later onset of decreased flow in the brain compared to the leg.
Discussion: It is known that sepsis causes changes in skeletal muscle microvasculature. If we see these same changes in the cerebral microvasculature, it may be an indication that there isn\u27t enough oxygen reaching the brain. This could be a cause of a decreased mental state, and would be worth further exploration
Field test of multi-hop image sensing network prototype on a city-wide scale
Open Access funded by Chongqing University of Posts and Telecommuniocations Under a Creative Commons license, https://creativecommons.org/licenses/by-nc-nd/4.0/Wireless multimedia sensor network drastically stretches the horizon of traditional monitoring and surveillance systems, of which most existing research have utilised Zigbee or WiFi as the communication technology. Both technologies use ultra high frequencies (mainly 2.4 GHz) and suffer from relatively short transmission range (i.e. 100 m line-of-sight). The objective of this paper is to assess the feasibility and potential of transmitting image information using RF modules with lower frequencies (e.g. 433 MHz) in order to achieve a larger scale deployment such as a city scenario. Arduino platform is used for its low cost and simplicity. The details of hardware properties are elaborated in the article, followed by an investigation of optimum configurations for the system. Upon an initial range testing outcome of over 2000 m line-of-sight transmission distance, the prototype network has been installed in a real life city plot for further examination of performance. A range of suitable applications has been proposed along with suggestions for future research.Peer reviewe
Prospective evaluation of artemether-lumefantrine for the treatment of non-falciparum and mixed-species malaria in Gabon
Background: The recommendation of artemisinin combination therapy (ACT) as first-line treatment for uncomplicated falciparum malaria is supported by a plethora of high quality clinical trials. However, their recommendation for the treatment of mixed-species malaria and the large-scale use for the treatment of non-falciparum malaria in endemic regions is based on anecdotal rather than systematic clinical evidence.
Methods: This study prospectively observed the efficacy of artemether-lumefantrine for the treatment of uncomplicated non-falciparum or mixed-species malaria in two routine district hospitals in the Central African country of Gabon.
Results: Forty patients suffering from uncomplicated Plasmodium malariae, Plasmodium ovale or mixed-species malaria (including Plasmodium falciparum) presenting at the hospital received artemether-lumefantrine treatment and were followed up. All evaluable patients (n = 38) showed an adequate clinical and parasitological response on Day 28 after oral treatment with artemether-lumefantrine (95% confidence interval: 0.91,1). All adverse events were of mild to moderate intensity and completely resolved by the end of study.
Conclusions: This first systematic assessment of artemether-lumefantrine treatment for P. malariae, P. ovale and mixed-species malaria demonstrated a high cure rate of 100% and a favourable tolerability profile, and thus lends support to the practice of treating non-falciparum or mixed-species malaria, or all cases of malaria without definite species differentiation, with artemether-lumefantrine in Gabon.
Trial Registration: ClinicalTrials.gov Identifier: NCT0072577
DIMETHYL N-CYANODITHIOIMINOCARBONATE AND TRIPHENYLPHOSPHINE OXIDE METAL HALIDE COMPLEXES: MOLECULAR CRYSTAL ELUCIDATION
Two MX2 (M = Ni, Zn; X = Cl, Br) dimethyl N-cyanodithioiminocarbonate compounds and one CrCl2 triphenylphosphine oxide complex were isolated and elucidated by single crystal X-ray crystallography. NiCl2[(CH3S)2C═NC≡N]2 (1) features inversion-related hydrogen bonded dimers linked into chains interacting through C-H···Cl growing layers along [110] whose junction into a 3D structure is enabled by H-bonds. ZnBr2[(CH3S)2C═NC≡N]2 (2) also exhibits inversion-related H-bonded dimers. In contrast with 1, the structure of 2 comprises chains along [110], connected via C-H···Br and C-H···S into a 2D layer along [-110]. CrCl2(OPPh3)2 (3) obtaining undergone redox processes, oxidizing [CH3C(O)CH2PPh3]+ to form PPh3PO, and reducing Cr from CrVI to CrII. In the structure, each molecule is linked to height neighbors through H-bonds affording a 3D network
Stabilizing contributions of sulfur-modified nucleotides: crystal structure of a DNA duplex with 2′-O-[2-(methoxy)ethyl]-2-thiothymidines
Substitution of oxygen atoms by sulfur at various locations in the nucleic acid framework has led to analogs such as the DNA phosphorothioates and 4′-thio RNA. The phosphorothioates are excellent mimics of DNA, exhibit increased resistance to nuclease degradation compared with the natural counterpart, and have been widely used as first-generation antisense nucleic acid analogs for applications in vitro and in vivo. The 4′-thio RNA analog exhibits significantly enhanced RNA affinity compared with RNA, and shows potential for incorporation into siRNAs. 2-Thiouridine (s(2)U) and 5-methyl-2-thiouridine (m(5)s(2)U) are natural nucleotide analogs. s(2)U in tRNA confers greater specificity of codon–anticodon interactions by discriminating more strongly between A and G compared with U. 2-Thio modification preorganizes the ribose and 2′-deoxyribose sugars for a C3′-endo conformation, and stabilizes heteroduplexes composed of modified DNA and complementary RNA. Combination of the 2-thio and sugar 2′-O-modifications has been demonstrated to boost both thermodynamic stability and nuclease resistance. Using the 2′-O-[2-(methoxy)ethyl]-2-thiothymidine (m(5)s(2)Umoe) analog, we have investigated the consequences of the replacement of the 2-oxygen by sulfur for base-pair geometry and duplex conformation. The crystal structure of the A-form DNA duplex with sequence GCGTAT*ACGC (T* = m(5)s(2)Umoe) was determined at high resolution and compared with the structure of the corresponding duplex with T* = m(5)Umoe. Notable changes as a result of the incorporation of sulfur concern the base-pair parameter ‘opening’, an improvement of stacking in the vicinity of modified nucleotides as measured by base overlap, and a van der Waals interaction between sulfur atoms from adjacent m(5)s(2)Umoe residues in the minor groove. The structural data indicate only minor adjustments in the water structure as a result of the presence of sulfur. The observed small structural perturbations combined with the favorable consequences for pairing stability and nuclease resistance (when combined with 2′-O-modification) render 2-thiouracil-modified RNA a promising candidate for applications in RNAi
Avantages des biodigesteurs sur le bois de chauffe dans les élevages laitiers à Kaolack (Sénégal)
Le déficit énergétique constitue une contrainte à l’épanouissement des ménages ruraux notamment, au niveau de l’énergie de cuisson. Les femmes utilisent le bois de chauffe pour les besoins énergétiques de la cuisson mais aussi, pour la pasteurisation du lait. Cette étude met en évidence les avantages de l’utilisation des biodigesteurs sur le bois de chauffe dans les élevages laitiers à Kaolack (Sénégal). Cent seize ménages ont été enquêtés dont 58 détenteurs de biodigesteurs. Les résultats montrent que les ménages possédant un biodigesteur avaient plus de temps pour se consacrer à des activités rémunératrices ou pour le bien être de la famille avec un tiers (32,75 %) qui mettent moins de 2 h par jour pour la recherche du bois et 2 h pour la cuisson d’un repas contre (67,25 %) de ménages sans biodigesteurs qui y consacraient 2 à 6 h par jour et plus de 3 h pour la cuisson d’un repas. Plus du quart (25,86 %) des ménages avec biodigesteurs utilisaient le biogaz comme source d’éclairage. De même, 36,20 % préparent les repas et pasteurisent le lait avec le biogaz. Il est également constaté une réduction de la fréquence des pathologies respiratoires et oculaires mais aussi des dépenses pour l’achat de combustible et de compost.Mots clés: Biogaz ; bois ; élevages laitiers ; économie des ménages ; Kaolack ; Sénégal Biodigester benefits on wood heating in dairy farming of Kaolack (Senegal)The energy deficit is a major constraint to the development of rural house holds including at cooking energy. Women use firewood for cooking energy needs but also for the pasteurization of milk. This study highlights the benefits of using biogas digesters on firewood in dairy farms in Kaolack (Senegal). One Hundred sixteen households were surveyed of which 58 possessed biodigester.The results show that households with a biodigester had much more time devoted to income-generating activities or for the welfare of the family. One third (32.75 %) of biodigester owners take less than 2 hours per day for wood search and 2 hours for cooking a meal against (67.25 %) of house holds without biodigester who spent 2 to 6 hours per day and put more than 3 hours to cook meal. More than a quarter (25.86 %) of households with biodigester used biogas as a lighting. Similarly, 36.20 % Cook food and pasteurize milk with biogas.The used of biogas expenses for the purchase of fuel as well as the compost for filed fertilization. It seem that biogas utilization reduce the incidence of respiratory and eye diseases.Keywords: Biogas ; wood ; dairy farms ; household economy ; Kaolack ; Senegal
DIFFICULTÉS DE LA PARTICIPATION EN RECHERCHE- ACTION : retour d'expériences de modélisation d'accompagnement en appui à l'aménagement du territoire au Sénégal et à la Réunion
International audienceComment aider les institutions et acteurs locaux à investir davantage les processus d'affectation des terres pour aménager leur territoire ? La décentralisation de l'aménagement du territoire engagée à la Réunion et au Sénégal est inachevée. Malgré l'arsenal législatif, les populations locales semblent peu impliquées dans les décisions les concernant en raison notamment de la difficulté à appréhender la complexité des systèmes d'interactions entre dynamiques sociales et environnementales. Le projet Domino vise à accompagner les processus de décision en proposant aux acteurs de construire et d'explorer des scenarii prospectifs d'affectation des terres. Cette expérience de modélisation participative repose sur une dynamique partenariale complexe sur chaque terrain, source de difficultés. Conscients des dérives potentielles, nous discutons la nécessité de construire une démarche qualité de notre recherche-action. Mots clés : montage de partenariat, démarche qualité, modèle, changement social, ComMod, interdisciplinarité, décentralisation, foncier, Sénégal, Réunio
Risk Factors for Dementia in a Senegalese Elderly Population Aged 65 Years and Over
Background: With the aging of the population, dementia is increasing worldwide. The objective of this study was to identify risk factors for dementia in an elderly population utilizing a primary health care service in Dakar, Senegal. Methods: Through a cross-sectional study conducted from March 2004 to December 31, 2005, 507 elderly patients aged ≥65 years who came to the Social and Medical Center of IPRES, Dakar, Senegal, were first screened with the screening interview questionnaire ‘Aging in Senegal’. Those who were cognitively impaired underwent a clinical examination to detect dementia. Univariate, bivariate, and multivariate logistic regression analyses were done. Results: The whole population had a mean age of 72.4 years (±5.2) and was mostly male, married, and non-educated. Hypertension, arthritis, and gastrointestinal diseases were the main health conditions reported in the past medical history. Smoking was important while alcohol consumption was rare. Social network was high. Forty-five patients (8.87%) had dementia. In the multivariate model, only advanced age, education, epilepsy, and family history of dementia were independently associated with dementia. Conclusion: The risk factors identified are also found in developed countries confirming their role in dementia. It is important to take dementia into consideration in Senegal and to sensitize the community for prevention
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