Spatio-temporal dynamics of population structure for macro invertebrates families in a continuum dam - effluent - river in irrigated system. Volta Basin (Burkina Faso)

A monthly sampling of benthic macro invertebrates was carried out at the hydro-agricultural dam of Boura in the Volta watershed basin (Burkina) during the period of February through July 2012 in order to describe the structuring of insect succession along with changes occurring in habitats of this irrigated dam farming system. The samples of insects were collected from 6 stations located inside the littoral (Station I), the sublittoral (Station II), the sewage channel or effluent (Stations III, IV, V) and the Mouhoun River (Station VI). The sampling method employed is a conventional method by the European Union named ” Directive Cadre sur l’Eau (DCE) ” recommended for the survey of benthic macro invertebrates. The survey reveals a community composed majorly of insects (more than 75%) variously distributed. On one hand at the shoreline and the coastal- adjoining zone in the dam, 23 families of macro invertebrates were identified; mostly belonging to the shoreline except for 10 families identified as endemic to the adjoining zone of the coastline. These two zones of the dam shelter the same malacological fauna consisting of the Unionidae, Lymneidae, Ampullariidae, Planorbidae, Valvatidae and Bulinidae families. The survey reveals otherwise that the differences between the Shannon biological diversity indices for these two zones were more pronounced during the month of July, the rainy period in the basin. On the other hand, concerning the dam-effluent-river continuum, a total of 35 families are sampled: 27 from dam water and stations near the irrigated zones; and 32 from the station of the sewage channel far from the irrigated zone and the river. The identification of individuals belonging to the family of the Baetidae and the Ephemerellidae (order of Ephemeroptera) in the river water highlights a subsequent reconstruction of the biodiversity in the river as the presence of both families is an indicator of fertile water. Further analysis on the spatial and temporal distribution involved 17 families out of the 35 sampled not common to all habitats. This lead to the conclusion that changes in natural habitats dictate the clustering patterns of macro invertebrates populations during the year long

Acute toxicity tests of two herbicides diuron and atrazine on the beetle Crenitis sp in Volta Basin, Burkina Faso

Acute toxicity tests were performed on Crenitis spp (Coleoptera; Hydrophilidae) using two herbicides, atrazine and diuron in the laboratory. The experiment was to investigate the effect of high doses of these pollutants in individually and together for 12 h each on Crenitis spp a species that abounds during the dry period in the shallow hydro-agricultural waters reservoirs of the Volta Basin. Individual macroinvertebrates were collected from puddle areas of the shoreline of Bama Reservoir in the Volta basin. The dry period is the period of rest for agricultural activities at the reservoir. Tests have shown that the toxic effects of the two herbicides on the species of beetles can be enhanced when the both products act synergistically. For diuron, the effective concentration that immobilizes 50% (EC50) of the insects is 44.96 g/l only, but drops to 11.72 g/l in the mixture; while in the same order, atrazine shows 11.75 g/l only and then drops to 7.33 g/l in synergy. It is concluded from this study that works on ecotoxicology should consider the additive or synergistic effects of herbicides to define the bio-ecological traits of macroinvertebrate species living in frequently polluted hydro-agricultural systems

Etude préliminaire de l’ichtyotoxicité des feuilles et tourteau de Balanites aegyptiaca et de tourteau de thé (Camellia sp) en vue de leurs utilisations comme piscicide d’aménagement des étangs piscicoles

Les feuilles et le tourteau de Balanites aegyptiaca et le tourteau de thé ont été étudiés pour leur toxicité au tilapia (Oreochromis niloticus). Les résultats ont notamment montré qu’avec le tourteau de B. aegyptiaca, à la concentration de 25 mg/l, 50% des poissons meurent en 2 heures 47 minutes et 100% meurent en 3 heures 10 minutes. Ces résultats sont de même ordre de grandeur que ceux obtenus avec le tourteau de thé pour lequel 50% des poissons meurent en 2 heures 37 minutes et 100% en 3 heures 23 minutes avec la concentration de 25 mg/l. Avec les macérés des feuilles de B. aegyptiaca, il faut jusqu’à 900 mg/l pour obtenir 50% de morts en 3 heures 37 minutes et 100% de morts en 4 heures 85 minutes. La réalisation des réactions de caractérisation a révélé la présence de 12 groupes chimiques dont des saponisides dans les feuilles de B. aegyptiaca qui pourraient expliquer cette performance d’ichtyotoxicité. Ces résultats suggèrent que le tourteau de B. aegyptiaca pourrait remplacer le tourteau de thé (ou saponine) comme piscicide dans les aménagements piscicoles.Mots clés: Balanites aegyptiaca, ichtyotoxique, feuilles, tourteaux, thé, tilapia d’élevag

Inventaire et distribution spatio-temporelle des macroinvertébrés bioindicateurs de trois plans d’eau du bassin de la Volta au Burkina Faso

Une étude des macroinvertébrés dans deux lacs de barrages hydro- agricoles (Bama et de Boura) et dans le lac naturel de Bala a permis de mettre en évidence la distribution spatio-temporelle des macroinvertébrésbioindicateurs de la qualité des eaux. La collecte des échantillons a été inspirée de la méthode conventionnelle de la Directive Cadre sur l’Eau de l’Union Européenne (DCE). L’étude a permis d’identifier 26405 individusde macroinvertébrés répartis en 71 espèces et 33 familles au total sur les trois sites de Bama (25 familles), Boura (23 familles) et Bala (30 familles). Les polluo-sensibles ont été décrites au lac naturel de Bala : des crustacés de l’ordre des Cladocères et 7 familles d’insectes (Gyrinidés, Pleidés, Baetidés Ephémérélidés, Tabanidés, Cératopogonidés et Canaceidés). L’étude a noté la présence de l’espèce Hydrocanthus ferruginicollis (Notéridés) particulièrement dominante dans les retenues hydro-agricoles de Bama (30,52% des Coléoptères) et Boura (27,32% des Coléoptères) ; tandis qu’elle ne représente que 7,51% des Coléoptères récoltés dans le lac naturel de Bala. Cette étude considère que les polluo-sensibles et les polluo-résitants décrits respectivement à Bala et à Bama et Boura peuvent être considérés comme de potentiels bioindicateurs des plans d’eau du bassin de la Volta.Mots clés : Macroinvertébrés, distribution, bioindicateurs, petits plans d’eau, bassin de la Volta, Burkina Faso

Etude de la toxicité des feuilles du pommier de Sodome du Sénégal et du tourteau de graines de thé chez le tilapia du Nil en aménagement piscicole

Les toxicités des feuilles du pommier de Sodome du Sénégal (Calotropis procera) et du tourteau de graines de thé (Camellia sp) chez le tilapia du Nil (Oreochromis niloticus) en pisciculture ont été étudiées. La réalisation des réactions de caractérisation chimique a révélé la forte présence des coumarines et d’anthocyanes mais seulement des traces de saponosides dans les feuilles de C. procera. Cependant elle n’a pas révélé la présence d’autres groupes particulièrement ichtyotoxiques. Les résultats ont notamment montré qu’avec les macérés aqueux de feuilles fraîches du pommier de Sodome du Sénégal, il faut une concentration de 10000 mg/l pour que 50% des poissons meurent en 4 heures 10 mn et 100% meurent en 5 heures 59 mn. Avec le tourteau de graines de thé, 50% de morts des poissons sont obtenus en 2 heures 37 mn et 100% de morts en 3 heures 23 mn avec la concentration de 25 mg/l. Ceci pourrait expliquer la relative faible ichtyotoxicité des macérés aqueux de feuilles du pommier de Sodome du Sénégal comparée à celle du tourteau de thé.Mots clés : Feuilles de Calotropis procera, ichtyotoxicité, tourteau, graines Camellia sp, tilapia du Nile d’élevage

Long-term changes in population size and the age-structure and sex-ratio of Waterbuck in a Sudanian savannah of Burkina Faso

The waterbuck (Kobus ellipsiprymnus), though widespread throughout Africa, is suspected to be declining overall. Data on population numbers and structure are lacking for many parts of its range, especially in West Africa, where the subspecies defassa is found. The aim of the present study was to evaluate the abundance, distribution and attributes of waterbuck populations in the Nazinga Forest Reserve, southern Burkina Faso. We investigated waterbuck population trends in the park using transect data collected in 1985-2019. For the more detailed analyses of population structure and distribution of the animals we used census data gathered during 2019. Most animals were adults (46.6%), and the sex ratio was heavily skewed towards females (5:1). Most animals were concentrated along the larger rivers. There was no influence of poacher activity on waterbuck distribution. In the long term (1985-2019), the population dynamics of waterbuck can be roughly divided into two main periods: a phase of population increase from 1985 to 2005, and one of ongoing population collapse from 2007-2019 Although the declining population trend was obvious, coefficients of determination were low indicating that the years explained poorly the number of individuals and the number of sightings obtained. Waterbuck numbers in the Nazinga Forest Reserve are declining, but we found no single reason to explain this trend. It is likely that a combination of factors, including global warming (increased aridity) and illegal activities such as poaching, are responsible. Because there are probably multiple reasons for the observed waterbuck population decline in our study area, we suggest that a multifaceted approach should be adopted in order to enhance the conservation status of the local waterbuck populations

A novel myelin P0–specific T cell receptor transgenic mouse develops a fulminant autoimmune peripheral neuropathy

Autoimmune-prone nonobese diabetic mice deficient for B7-2 spontaneously develop an autoimmune peripheral neuropathy mediated by inflammatory CD4+ T cells that is reminiscent of Guillain-Barré syndrome and chronic inflammatory demyelinating polyneuropathy. To determine the etiology of this disease, CD4+ T cell hybridomas were generated from inflamed tissue–derived CD4+ T cells. A majority of T cell hybridomas were specific for myelin protein 0 (P0), which was the principal target of autoantibody responses targeting nerve proteins. To determine whether P0-specific T cell responses were sufficient to mediate disease, we generated a novel myelin P0–specific T cell receptor transgenic (POT) mouse. POT T cells were not tolerized or deleted during thymic development and proliferated in response to P0 in vitro. Importantly, when bred onto a recombination activating gene knockout background, POT mice developed a fulminant form of peripheral neuropathy that affected all mice by weaning age and led to their premature death by 3–5 wk of age. This abrupt disease was associated with the production of interferon γ by P0-specific T cells and a lack of CD4+ Foxp3+ regulatory T cells. Collectively, our data suggest that myelin P0 is a major autoantigen in autoimmune peripheral neuropathy

Changing the Paradigm for Management of Pediatric Primary Spontaneous Pneumothorax: A Simple Aspiration Test Predicts Need for Operation

Purpose Chest tube (CT) management for pediatric primary spontaneous pneumothorax (PSP) is associated with long hospital stays and high recurrence rates. To streamline management, we explored simple aspiration as a test to predict need for surgery. Methods A multi-institution, prospective pilot study of patients with first presentation for PSP at 9 children’s hospitals was performed. Aspiration was performed through a pigtail catheter, followed by 6 h observation with CT clamped. If pneumothorax recurred during observation, the aspiration test failed and subsequent management was per surgeon discretion. Results Thirty-three patients were managed with simple aspiration. Aspiration was successful in 16 of 33 (48%), while 17 (52%) failed the aspiration test and required hospitalization. Twelve who failed aspiration underwent CT management, of which 10 (83%) failed CT management owing to either persistent air leak requiring VATS or subsequent PSP recurrence. Recurrence rate was significantly greater in the group that failed aspiration compared to the group that passed aspiration [10/12 (83%) vs 7/16 (44%), respectively, P = 0.028]. Conclusion Simple aspiration test upon presentation with PSP predicts chest tube failure with 83% positive predictive value. We recommend changing the PSP management algorithm to include an initial simple aspiration test, and if that fails, proceed directly to VATS

Understanding the Value of Tumor Markers in Pediatric Ovarian Neoplasms

Purpose The purpose of this study was to determine the diagnostic accuracy of tumor markers for malignancy in girls with ovarian neoplasms. Methods A retrospective review of girls 2–21 years who presented for surgical management of an ovarian neoplasm across 10 children's hospitals between 2010 and 2016 was performed. Patients who had at least one concerning feature on imaging and had tumor marker testing were included in the study. Sensitivity, specificity, and negative and positive predictive values (PPV) of tumor markers were calculated. Results Our cohort included 401 patients; 22.4% had a malignancy. Testing for tumor markers was inconsistent. AFP had high specificity (98%) and low sensitivity (42%) with a PPV of 86%. The sensitivity, specificity, and PPV of beta-hCG was 44%, 76%, and 32%, respectively. LDH had high sensitivity (95%) and Inhibin A and Inhibin B had high specificity (97% and 92%, respectively). Conclusions Tumor marker testing is helpful in preoperative risk stratification of ovarian neoplasms for malignancy. Given the variety of potential tumor types, no single marker provides enough reliability, and therefore a panel of tumor marker testing is recommended if there is concern for malignancy. Prospective studies may help further elucidate the predictive value of tumor markers in a pediatric ovarian neoplasm population

Dynamique de structuration spatio-temporelle des populations de familles de macroinvertébrés dans un continuum lac de barrage-effluent-fleuve issu de périmètre irrigué. Bassin de la Volta (Burkina Faso)

Objective: A monthly sampling of benthic macroinvertebrates was done at the hydro-agricultural of dam Boura in the basin of the Volta (Burkina) during the period of February to July 2012 in order to describe the structuring of insect succession along with changes occurring in habitats of this irrigation system. Methodology and results: The samples of insects were collected from 6 stations placed on the shoreline (Station I), the adjoining zone to the coastline (Station II), the sewage channal (stations III, IV that is located at midsection of the irrigated area and the Station V far away from this area) and the Mouhoun stream (Station VI); the sampling method used conventional method the European Union named " Directive Cadre sur l’Eau (DCE) " advised for the sampling of the benthics macroinvertebrates. The survey revealed a community composed in majority of insects (more of 75%) and sparsely distributed. On one hand at the shoreline and the coastal- adjoining zone in the lake of dam, 23 families of macroinvertebrates were sampled; they mostly belong to the shoreline except for 10 families identified in the adjoining zone to the coastline. These two zones of the dam shelter the same malacological fauna consisting of the families of Unionidae, Lymneidas, Ampullariidae, Planorbidae, Valvatidae and Bulinidae. The survey revealed otherwise that the difference between the biological diversity indices of Shannon of these two zones was more pronounced during the month of July, period of rain in the basin., concerning the dam-sewage channal-river continuum, a total of 35 families were sampled: 27 from dam water and stations near the irrigated zones; and 32 been collected from the station of the sewage channel far from the irrigated perimeter and from the stream. The identification of individuals belonging to the family of the Baetidae and the Ephemerellidae (order of the Ephemeroptera) in the river water highlights a possible reconstruction of biodiversity in the river because both two families are indicator fertile water. Conclusion and application of results: it is concluded of this survey that the agricultural hydro amenities have an influence on the spatio-temporal structuring of the macroinvertebrates. The results of this survey can be used otherwise to keep biodiversity and the restoration of these ecosystems continually impacted.Keywords: macroinvertebrates; succession; continuum; hydro-agricultural dams; irrigation; river; Mouhoun; Volta basin