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Search Results: 1 - 10 of 340349 matches for " Roger C. H.;Zeba "
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Antiacetylcholinesterase and antioxidant activity of essential oils from six medicinal plants from Burkina Faso
Martin Kiendrebeogo,Ahmed Y. Coulibaly,Roger C. H. Nebie,Boukaré Zeba
Revista Brasileira de Farmacognosia , 2011,
Abstract: In this investigation, we evaluated essential oils from six medicinal plants from Burkina Faso for their antiacetylcholinesterase and antioxidant abilities. The chemotype of most active were also determined. The best antiacetylcholinesterase activities were recorded for the essential oils of Eucalyptus camaldulensis (IC50 18.98 μ g/mL) and Ocimum canum (IC50 36.16 μ g/mL). Their chemotype have been related to the 1,8-cineole one. Both essential oils demonstrated a linear mixed non competitive inhibition. The essential oil of Ocimum basilicum which belong to the linalool-eugenol chemotype exhibited the best radical scavenging activity (IC50 3.82 μ g/mL) and reducing power (531.75 mg AAE/g). In comparison with gallic and ascorbic acids, O. basilicum essential oil evidenced interesting antioxidant activities. The antiacetylcholinesterase and antioxidant activities of essential oils were discussed in regard with their chemical composition.
Antiacetylcholinesterase and antioxidant activity of essential oils from six medicinal plants from Burkina Faso
Kiendrebeogo, Martin;Coulibaly, Ahmed Y.;Nebie, Roger C. H.;Zeba, Boukaré;Lamien, Charles E.;Lamien-Meda, Aline;Nacoulma, Odile G.;
Revista Brasileira de Farmacognosia , 2011, DOI: 10.1590/S0102-695X2011005000008
Abstract: in this investigation, we evaluated essential oils from six medicinal plants from burkina faso for their antiacetylcholinesterase and antioxidant abilities. the chemotype of most active were also determined. the best antiacetylcholinesterase activities were recorded for the essential oils of eucalyptus camaldulensis (ic50 18.98 μ g/ml) and ocimum canum (ic50 36.16 μ g/ml). their chemotype have been related to the 1,8-cineole one. both essential oils demonstrated a linear mixed non competitive inhibition. the essential oil of ocimum basilicum which belong to the linalool-eugenol chemotype exhibited the best radical scavenging activity (ic50 3.82 μ g/ml) and reducing power (531.75 mg aae/g). in comparison with gallic and ascorbic acids, o. basilicum essential oil evidenced interesting antioxidant activities. the antiacetylcholinesterase and antioxidant activities of essential oils were discussed in regard with their chemical composition.
Water Intrusion in the Chesapeake Bay Region: Is It Caused by Climate-Induced Sea Level Rise?  [PDF]
Roger H. Bezdek
Journal of Geoscience and Environment Protection (GEP) , 2017, DOI: 10.4236/gep.2017.58020
Abstract: Sea level rise due to climate change is a contentious issue with profound geographic and economic implications. One region in the USA identified as being particularly susceptible to seal level rise is the Chesapeake Bay region, and it has been estimated that by the end of the century Norfolk, Virginia could experience sea level rise of 0.75 meters to more than 2.1 meters. Water intrusion is a serious problem in much of the Chesapeake Bay region. The question addressed here is whether this water intrusion is the result of climate-induced seal level rise or is being caused by other factors. Our findings indicate that the water intrusion problems in the region are due not to “sea level rise”, but primarily to land subsidence due to groundwater depletion and, to a lesser extent, subsidence from glacial isostatic adjustment. We conclude that water intrusion will thus continue even if sea levels decline. These findings are critical because the water intrusion problems in the Chesapeake Bay—and elsewhere—cannot be successfully solved unless their causes are correctly identified and appropriate remedies are devised. For the Chesapeake Bay region, the required remedy is the reversal of groundwater withdrawal rates, which has been used successfully elsewhere in the USA and other nations to solve water intrusion problems.
COMBINED APPLICATION OF TRIAAND POTASSIUM STIMULATES THE GEL CONTENT, MORPHOLOGICALAND BIOCHEMICAL CHARACTERISTICS OF ALOE VERA
SABA IQBAL , M. MASROOR A. KHAN,ZEBA H. KHAN
Golden Research Thoughts , 2012, DOI: 10.9780/22315063
Abstract: Aloe barbadensis (A. barbadensis L.) Miller, commonly known as aloe vera is extensively used as a base element in preparation of medicine, cosmetics and food supplements. The objective of this study was to find out the stimulatory effect of varying levels of triacontanol (TRIA) in combination with different concentrations of potassium (K) on morphological and biochemical characteristics of aloe vera plants. Treatments included four levels of TRIA (10-0, 10-5, 10-6 and 10-7M) together three concentrations of K (K0, K50 and K100kg/ha). K was applied through basal application whereas TRIAwas given by foliar application using a hand spryer. After 12 months growing leaf length, width, number and fresh weight, shoot fresh weight, gel content, nitrogen, potassium and protein contents were measured. Results indicate that the all growth and biochemical characteristics of aloe Vera were highest with the treatment K5010-6M TRIA. Among the TRIA treatments all characteristics were increases from 10-7 to 10-6 but 10-5 have inhibitory effect at which growth and biochemistry of aloe vera were slightly decreases. Among K treatment K50 proved optimum along with 10-6M TRIA.
Significance of Sulphur nutrition against metal induced oxidative stress in plants
Mohd Mazid,Khan Zeba H.,Saima Quddusi,Taqi Ahmed Khan
Journal of Stress Physiology & Biochemistry , 2011,
Abstract: Sulphur (S) is available to plants as sulphate (SO42-) in the soil to the roots and as gaseous SO2 in the atmosphere to the shoots. Of all the macronutrient, S is perhaps the nutrient which has attracted the most attention in soil science and plant nutrition due to its potential defensive characteristics to pests, good nutritive potentiality to crops and its relative immobility in the soil-plant system. This review highlights the mechanisms of uptake and translocation of S from soil and its transport in xylem and phloem tissues of plants. Moreover, it also throws new insights, have led us to revisit the hypothesis of S chelation in reference to oxidative stress induced by heavy metals sequestration.
Human Papillomaviruses Prevalence and Genital Co-infections in HIV-seropositive Women in Ouagadougou (Burkina Faso)
T. Sagna,F. Djigma,M. Zeba,C. Bisseye
Pakistan Journal of Biological Sciences , 2010,
Abstract: The vaginal swabs among HIV-positive women in Africa often revealed opportunistic infections such as human Papillomavirus (HPV) and Mycoplasma that induce respectively cervix cancer and diseases such as vaginosis, abortions, infertility in through salpingitis. The purposes of this study were to: (1) seek for, the prevalence of pathogens such as HPV and Mycoplasma; (2) characterize the strains of HPV and estimate their prevalence; (3) identify among these women, those who were co-infected by these pathogens in order to cure them. From February 2009 to January 2010, 156 HIV-positive women attending our medical centers and aged from 19-45 years (mean age 33.65±5.75 years) had voluntarily accepted vaginal specimen’s tests. PCR, ELISA and molecular hybridization were used for the identification and characterization of these pathogens. The results revealed the presence of Mycoplasma and HPV in 25.64 and 58.33% cases, respectively. The following HPV genotypes and the following prevalence were recorded: HPV-50'S (24.11%), HPV-18 (21.28%), HPV-30'S (18.44%) and HPV-16 (5.67%). The study also enable the identification of co-infections such as HPV-18 strains with HPV-30'S (5.67%) and HPV-30'S with HPV-50'S (3.55%). Other germs infecting the female genital tract including Candida albicans (20.51%), Escherichia coli (12.18%), Treponema pallidum (3.85%), Streptococcus agalactiae (3.21%) and Staphylococcus aureus (1.92%) were isolated. This preliminary research work showed the incidence of several genital pathogens, this could be a springboard for nationwide epidemiological study on HPV strains circulating in Burkina Faso.
Antimicrobial Resistance and Serotype Distribution of Streptococcus pneumoniae Strains Causing Childhood Infection in Burkina Faso
Leonard C. Bere,Jacques Simpore,Simplice D. Karou,Boukare Zeba
Pakistan Journal of Biological Sciences , 2009,
Abstract: In Burkina Faso, a Western African country, reports on pneumococci carriage, resistance patterns and serotypes are inconsistent. The present study was conducted in order to evaluate these parameters. Thus 860 nasopharyngeal swabs were collected from children attending vaccination centers for pneumococci isolation, identification and serotype determination. The susceptibility to 16 antibiotics was assayed as recommended by the National Committee for Clinical Laboratory Standard (NCCLS). The results revealed that the majority of children were of 2 to 24 months age and 73.4% of children were well vaccinated. A carriage rate of 50.6% was recoded among the children. The main serotypes were: 6 (22.22%); 23 (16.67%); 7 and 9 (3.70%); 4, 11, 14, 15, 20 and 24 (1.85%). Serotypes19, 23, 6, 7 and 18 were linked to penicillin resistance. Globally, high resistance rates to: amikacin, tetracyclin, pefloxacin, cotrimoxazol and penicillins (resistance rates greater than 25%) were recorded; however the following antibiotics remained active on the strains: rifampicin, ceftriaxone, erythromycin, spectinomycin, chloramphenicol, vancomycin, lincomycin and ciprofloxacin.
The radio emission from the Galaxy at 22 MHz
R. S. Roger,C. H. Costain,T. L. Landecker,C. M. Swerdlyk
Physics , 1999, DOI: 10.1051/aas:1999239
Abstract: We present maps of the 22MHz radio emission between declinations -28d and +80d, covering ~73% of the sky, derived from observations with the 22MHz radiotelescope at the Dominion Radio Astrophysical Observatory (DRAO). The resolution of the telescopt (EWxNS) is 1.1d x 1.7d secant(zenith angle). The maps show the large scale features of the emission from the Galaxy including the thick non-thermal disk, the North Polar Spur (NPS) and absorption due to discrete HII regions and to an extended band of thermal electrons within 40d of the Galactic centre. We give the flux densities of nine extended supernova remnants shown on the maps.
Overview of -lactamase incidence on bacterial drug resistance
B Zeba
African Journal of Food, Agriculture, Nutrition and Development , 2004,
Abstract: The bacterial drug resistance is its ability to grow in presence of high concentration of an antibiotic. The massive and often unsuitable use of antibiotic tends to select the resistant mutants that are then disseminated. The ß-lactam antibiotics represent an antibiotic family widely used because of their remarkable tolerance by animal organism. This practice generated the resistance from many bacteria in clinical and environmental spaces. One of the main drug resistance mechanism used by bacteria is the production of inactivation enzymes named ß-lactamases. This mini review attempts to pinpoint the ß- lactamase incidence on the failure of clinical treatment using ß-lactam antibiotic anywhere.
The “Parahippocampal Place Area” Responds Preferentially to High Spatial Frequencies in Humans and Monkeys
Reza Rajimehr,Kathryn J. Devaney,Natalia Y. Bilenko,Jeremy C. Young,Roger B. H. Tootell
PLOS Biology , 2012, DOI: 10.1371/journal.pbio.1000608
Abstract: Defining the exact mechanisms by which the brain processes visual objects and scenes remains an unresolved challenge. Valuable clues to this process have emerged from the demonstration that clusters of neurons (“modules”) in inferior temporal cortex apparently respond selectively to specific categories of visual stimuli, such as places/scenes. However, the higher-order “category-selective” response could also reflect specific lower-level spatial factors. Here we tested this idea in multiple functional MRI experiments, in humans and macaque monkeys, by systematically manipulating the spatial content of geometrical shapes and natural images. These tests revealed that visual spatial discontinuities (as reflected by an increased response to high spatial frequencies) selectively activate a well-known place-selective region of visual cortex (the “parahippocampal place area”) in humans. In macaques, we demonstrate a homologous cortical area, and show that it also responds selectively to higher spatial frequencies. The parahippocampal place area may use such information for detecting object borders and scene details during spatial perception and navigation.
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