573 research outputs found

    Adding ROS Scavengers to Cold K\u3csup\u3e+\u3c/sup\u3e Cardioplegia Reduces Superoxide Emission During 2 h Global Cold Cardiac Ischemia

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    We reported that the combination of reactive oxygen species (ROS) quenchers Mn(III) tetrakis (4-benzoic acid) porphyrin (MnTBAP), catalase, and glutathione (MCG) given before 2 hours cold ischemia better protected cardiac mitochondria against cold ischemia and warm reperfusion (IR)-induced damage than MnTBAP alone. Here, we hypothesize that high K+ cardioplegia (CP) plus MCG would provide added protection of mitochondrial bioenergetics and cardiac function against IR injury. Using fluorescence spectrophotometry, we monitored redox balance, ie reduced nicotinamide adenine dinucleotide and flavin adenine dinucleotide (NADH/FAD), superoxide (O2 •−), and mitochondrial Ca2+ (m[Ca2+]) in the left ventricular free wall. Guinea pig isolated hearts were perfused with either Krebs Ringer’s (KR) solution, CP, or CP + MCG, before and during 27°C perfusion followed immediately by 2 hours of global ischemia at 27°C. Drugs were washed out with KR at the onset of 2 hours 37°C reperfusion. After 120 minutes warm reperfusion, myocardial infarction was lowest in the CP + MCG group and highest in the KR group. Developed left ventricular pressure recovery was similar in CP and CP + MCG and was better than in the KR group. O2 •−, m[Ca2+], and NADH/FAD were significantly different between the treatment and KR groups. O2 •− was lower in CP + MCG than in the CP group. This study suggests that CP and ROS quenchers act in parallel to improve mitochondrial function and to provide protection against IR injury at 27°C

    Comparison of Cumulative Planimetry versus Manual Dissection to Assess Experimental Infarct Size in Isolated Hearts

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    Introduction Infarct size (IS) is an important variable to estimate cardiac ischemia/reperfusion injury in animal models. Triphenyltetrazolium chloride (TTC) stains viable cells red while leaving infarcted cells unstained. To quantify IS, infarcted and non-infarcted tissue is often manually dissected and weighed (IS-DW). An alternative is to measure infarcted areas by cumulative planimetry (IS-CP). Methods We prospectively compared these two methods in 141 Langendorff-prepared guinea pig hearts (1.44 ± 0.02 g) that were part of different studies on mechanisms of cardioprotection. Hearts were perfused with Krebs–Ringer\u27s and subjected to 30 min global ischemia after various cardioprotective treatments. Two hours after reperfusion hearts were cut into 6–7 transverse sections (3 mm) and stained for 5 min in 1% TTC and 0.1 M KH2PO4 buffer (pH 7.4, 38 °C). Each slice was first scanned and its infarcted area measured with Image 1.62 software (NIH). Infarctions in individual slices of each heart were averaged (IS-CP) on the basis of their weight. After scanning, IS-DW was determined by careful manual dissection of infarcted from non-infarcted tissue and measuring their respective total weight. Results We found limited tissue permeation of TTC in relation to the slice thickness leaving tissue in the center unstained, as well as significant cross-contamination of stained vs. unstained tissue after manual dissection. IS-CP and IS-DW ranged from 6.0 to 73.1% and 19.4 to 70.5%, respectively, and correlated as follows: IS-DW = (27.6 ± 1.4) + (0.518 ± 0.038) • IS-CP; r = 0.75 (Pearson), p \u3c 0.001. In addition, IS-CP correlated better with return of function after reperfusion like developed left ventricular pressure, contractility and relaxation, and myocardial oxygen consumption. Discussion Despite a good correlation between both methods, limited tissue permeation by TTC diffusion and limited precision in the ability to manually dissect stained from unstained tissue leads to an overestimation of infarct size by dissection and weighing compared to cumulative planimetry

    Champ ecole paysan, une approche participative pour l’amelioration du rendement du niebe: resultats d’experiences pilotes conduites dans les regions de Maradi et Zinder au Niger

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    En vue de favoriser les interactions entre groupes de producteurs pour résoudre les problèmes de production et diffuser les technologies éprouvées, en culture du niébé, trente champs écoles ont été mis en place de 2013 à 2014 au centre sud du Niger avec 600 producteurs dans les départements de Guidan Roumdji, Madarounfa, Magarria, Tanout et la commune de Droum. La fumure organique (5tha-1) et l’engrais minéral NPK, 15 - 15 - 15 (60kg ha-1). Et la combinaison des deux ont été appliqués pour améliorer la fertilité des sols. La protection des cultures contre les ravageurs a été assurée par des extraits aqueux de graines de neem (Azadirecta indica) appuyé par certains composés chimiques. Pour les essais variétaux, le rendement moyen en grains le plus important (1074 kg ha-1) a été obtenu avec la variété améliorée IT90K 372 - 1- 2 sur les deux années d’essais. Les génotypes IT99K 573 - 1 - 1 ; IT89KD 374 - 57 ; TN 5 - 78 ; IT97 K 499 - 38 ; KVX 30 - 309 - 6G ont donné des rendements moyens (entre 649 et 812 kg ha-1). La combinaison fumure organique et minérale a entrainé une augmentation du rendement moyen du niébé de 323 %, par rapport au témoin. Les extraits aqueux de graines de neem ont permis de réduire des attaques des ravageurs tels que : Clavigralla tomentosicollis (Stal.), Aphis craccivora Koch et Maruca vitrata Geyer avec une augmentation de rendement de 258 %. L’itinéraire technique combinant : variétés améliorées, respect des écartements, protection des cultures et apport fertilisants minéraux a permis d’augmenter le rendement de niébé de 113 %.Mots clés : Niébé Vigna unguiculata, insecticide, variété locale, variété améliorée, biopesticide

    KATP Channel Openers Have Opposite Effects on Mitochondrial Respiration Under Different Energetic Conditions

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    Mitochondrial (m) KATP channel opening has been implicated in triggering cardiac preconditioning. Its consequence on mitochondrial respiration, however, remains unclear. We investigated the effects of two different KATP channel openers and antagonists on mitochondrial respiration under two different energetic conditions. Oxygen consumption was measured for complex I (pyruvate/malate) or complex II (succinate with rotenone) substrates in mitochondria from fresh guinea pig hearts. One of two mKATP channel openers, pinacidil or diazoxide, was given before adenosine diphosphate in the absence or presence of an mKATP channel antagonist, glibenclamide or 5-hydroxydecanoate. Without ATP synthase inhibition, both mKATP channel openers differentially attenuated mitochondrial respiration. Neither mKATP channel antagonist abolished these effects. When ATP synthase was inhibited by oligomycin to decrease [ATP], both mKATP channel openers accelerated respiration for both substrate groups. This was abolished by mKATP channel blockade. Thus, under energetically more physiological conditions, the main effect of mKATP channel openers on mitochondrial respiration is differential inhibition independent of mKATP channel opening. In contrast, under energetically less physiological conditions, mKATP channel opening can be evidenced by accelerated respiration and blockade by antagonists. Therefore, the effects of mKATP channel openers on mitochondrial function likely depend on the experimental conditions and the cell\u27s underlying energetic state

    Perception de la Dégradation des Terres et Adoption des Technologies de Conservation des Eaux et des Sols au Nord du Burkina Faso : le cas du Zaï et des Cordons Pierreux

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    This study is based on data collected from 141 family-type farms in the Yatenga province in Burkina Faso. A probit approach is used to analyze the effect of perception of land degradation and other factors on the adoption of zaï and stone rows. The results of the estimation show that the availability of organic matter from small ruminants is determinant for the adoption of both zaï and stone rows. Although most of farmers are aware of the causes and consequences of land degradation, this factor does not significantly impact on farmers’ decision to invest in SWC measures. Opportunities do exist for making more efficient use of local sources of nutrients, such as small ruminants’ organic matter in combination with locally accepted SWC measures. This may increase farmers’ willingness to go beyond SWC measures, to invest in nutrient supply in their soils which are characterized by poor fertility. The study shows that combining training on SWC and the development of small-scale animal breeding could contribute to reach this goal in a degraded area.Land degradation, technology adoption, stone rows, Zai, Yatenga, Community/Rural/Urban Development, Consumer/Household Economics, Environmental Economics and Policy, Food Consumption/Nutrition/Food Safety, Food Security and Poverty, Labor and Human Capital, Land Economics/Use, Marketing, Research and Development/Tech Change/Emerging Technologies,

    Perception des paysans sur la contrainte de la mineuse de l'épi Heliocheilus albipunctella De Joannis, ravageur important du mil en zone sahélienne

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    Heliocheilus albipunctella De Joannis est un important ravageur des épis du mil en zone sahélienne. Pour documenter la perception des paysans par rapport à ce ravageur, une enquête a été réalisée en avril 2016 avec un échantillon de 732 producteurs dans cinq principales régions agricoles du Niger. Les résultats obtenus ont montré que: 1) 17 % des répondants ont pu décrire le cycle biologique de H. albipunctella; 2) le ravageur cause en moyenne 43 à 82 % de perte de production, une moyenne obtenue depuis 28 ans selon les régions; 3) 37 à 78 % des producteurs savent que les infestations des épis du mil sont favorisées par les semis précoces, les sécheresses et la nature sableuse du sol; 4) d'après la moitié des répondants le plus de dégâts sont observés au stade grenaison du mil; 5) plus de 80 % des producteurs ne connaissent aucune méthode de lutte contre ce ravageur. Ces informations interpellent sur l'incidence négative de H. albipunctella sur le rendement du mil dans ces zones précaires. La nécessité de développer un programme participatif de gestion intégrée de ce ravageur est recommandée

    Valeur diagnostique de la tomodensitométrie dans la cysticercose cérébrale à Lomé

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    La cysticercose a une prévalence élevée dans les pays sub-sahariens et son diagnostic reste difficile. Cette étude a pour but de déterminer la valeur diagnostique de la tomodensitométrie dans la cysticercose  cérébrale. Recrutement des patients ayant bénéficié d'une  tomodensitométrie cérébrale dans l'une des circonstances suivantes: épilepsie, hypertension intracrânienne, syndrome pyramidal, détérioration mentale, ataxie locomotrice ou une diminution de l'acuité visuelle. Les critères de Del Brutto et al. avaient permis de retenir le diagnostic positif de cysticercose cérébrale. Pendant la période, 4193 patients avaient été inclus à l'étude, dont 140 cas de cysticercose cérébrale (3,3%). L'âge moyen des patients de cysticercose cérébrale était de 36 ± 14 ans, avec des extrêmes de 17 ans et 59 ans. La sensibilité et la spécificité de la tomodensitométrie dans la cysticercose cérébrale sont respectivement de 96,4% et 98,3%. La valeur prédictive positive et la valeur prédictive  négative de la tomodensitométrie sont respectivement de 65,9% et  99,8%. Les aspects  tomodensitométriques chez les vrais positifs sont dominés par des lésions associées, 72 cas (53,3%), suivies d'une hypodensité nodulaire arrondie unique ou multiple sans prise de contraste iodée, 17cas (12,6%). La TDM est une technique d'imagerie qui a une sensibilité et une spécificité élevées dans le diagnostic de la cysticercose cérébrale. Cependant, les autres critères de diagnostic restent utiles du fait de l'existence de nombreux cas de faux positifs à la tomodensitométrie

    Revue Des Doses d’Exposition Et Des Methode d’Optimisation En Tomodensitometrie (TDM) De l’Enfant Au Togo

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    Objectives: To assess the justification of indications of CT scans and the exposure doses of children during CT scans. Methods: Prospective study of 104 CT-sans of children collected over a period of 6 months. Results: Female children were predominant with a sex ratio female / male of 1.2. The predominant age group was the 10 to 15 years (41%). The CT-Scan of the head was the most practiced exam, with 64.42% (67/104). When analyzing information according to the recommendations of the Guide of well practices of French Society of Radiology (SFR) and the French Society of Biophysics and Nuclear Medicine (SFBMN), only 77% of CT-Scans were justified. Almost half (49.04%) of CT-Scans had a CT-Dose Index (CTDI) and Dose Length Product (DLP) greater than the French reference norms defined for each group of age. The average values of CTDI and DLP are above the norms for all CT-scans of the skull, facial bones and sinuses. Conclusion: The doses administered to children by CT-Scans are above accepted norms. Improved practices continue medical training of radiology manipulators and the creation of a regulatory or an agency of radioprotection is necessary

    Echographie Pédiatrique En Pratique Hospitaliere Au Centre Hospitalier Universitaire (CHU) De Kara Au Togo

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    Purpose: To list pediatric ultrasound exams performed at Kara University Hospital Center in Togo and the pathologies observed. Materials and methods: This was a retrospective and descriptive study of the results of pediatric ultrasound examinations performed in the Department of Radiology and Imaging of Kara University Hospital Center. The study ran from January 1, 2013 to December 31, 2016, over a period of 3 years. Results: The frequency of pediatric ultrasounds was 5.1%. The average age of the patients was 2.16 years with extremes of 1 day to 15 years. There was a male predominance with a sex ratio of 1.4. Abdomino-pelvic ultrasound were the most represented, 92%, followed by cervical ultrasound in 2.6% of cases. Abdominal ultrasound indications were dominated by abdominal pain in 33.6% of cases, followed by palpation of abdominal mass in 15.7%. Cervical ultrasounds were motivated in 5 out of 8 cases by the cervical swelling. Abdomino-pelvic ultrasonography was pathological in 70.1% of cases. Hepatic affections were the most common abdominal abnormality in 37.8% of cases followed by splenic disorders. Hepatic lesions were dominated by European Scientific Journal February 2018 edition Vol.14, No.6 ISSN: 1857 – 7881 (Print) e - ISSN 1857- 7431 444 homogeneous hepatomegaly with 63.2% of cases. Cervical ultrasound was pathological in 6 out of 8 cases. The lesions observed were mainly cervical lymphadenopathy (4 cases out of 6). Conclusion: Ultrasound is a very useful tool in the exploration of pediatric diseases. The abdominal ultrasound is the most performed and hepatic pathologies are the most common
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