IN VITRO ANTIPLATELET ACTIVITY OF AN ISOFLAVANONE ISOLATED FROM METHANOLIC EXTRACT OF EMBLICA OFFICINALIS FRUITS

Objective: In this study, we aimed to isolate a polyphenolic compound from a polyphenolic-rich fraction from Emblica officinalis fruits and also study its effect on adenosine diphosphate (ADP) and collagen-induced in vitro platelet aggregation. Methods: The polyphenolic-rich fraction was prepared by 80% methanolic extraction. The residue was extracted successively with hexane, benzene, ethyl acetate and n-butanol. Ethyl acetate residue was selected for column chromatography because of its high polyphenolic content. It was subjected to repeated column chromatography of series with different eluents of increasing polarity. A brown amorphous powder was obtained from ethyl acetate: methanol (7:3) fraction. This sample was subjected to UV-visible spectrum, IR spectrum, 1H NMR, 13C NMR and electrospray mass spectrum (ES-MS) studies for its structural elucidation. Results: A compound, 5, 7, 4'-trihydroxy 3'-methoxy isoflavanone was identified from polyphenolic rich ethyl acetate: methanol (7:3) fraction separated from the 80% methanolic extract of Embica officinalis fruits by repeated column chromatography. Yield of the compound was 421.05 mg/kg. This compound exhibited antiplatelet activity well comparable with that of quercetin. Conclusion: The present study proved that the isolated compound 5, 7, 4'-trihydroxy 3'-methoxy isoflavanone exerts a significant inhibitory activity on ADP and collagen-induced in vitro platelet aggregation, which can be considered as an effective remedy for alleviating complications of cardiovascular diseases

Urban growth assessment and its impact on deforestation in Bauchi metropolis, Nigeria using remote sensing and GIS techniques

Urban areas are rapidly expanding due to population growth and development, leading to deforestation and land degradation. This study employed remote sensing and GIS techniques to assess urban growth and its impact on deforestation in Bauchi metropolis, Nigeria within the last three decades (1986-2016). The study made use of Land sat images of four epochs; Thematic Mapper (TM) of 1986 and 1996, Enhanced Thematic Mapper of 2006, and Operational Land Imager (OLI) of 2016. Color compositions were made after which the images were geometrically and radio metrically restituted. The images were classified using maximum likelihood algorithm and the accuracy of the classification was assessed by cross-validation using confusion matrices and ground truthing by the use of a hand-held Global Positioning System (GPS). The classified images with their kappa indexes were TM of 1986 (0.83%) and 1996 (0.87%), ETM+ of 2006 (0.90%) and OLI of 2016 (0.92%), respectively. Post-classification comparisons and analyses were performed and the results revealed that changes have taken place in bare surface (+32.43%), built-up area (+565.24%), farm land (+66.42%), forest (-91.80%) and rock outcrop (-49.21%) in the metropolis between 1986 and 2016. The land cover features of the metropolis were reclassified into forest and non-forest for cross-tabulation analysis and the result of the analysis indicates a change-over of 14965.97Ha (39.68%) form forest to non-forest (deforestation) and that of 467.69Ha (1.24%) form non-forest to forest (afforestation) between 1986 and 2016. This shows a rapid increase in built-up area (urban growth) and rapid decrease in forest (deforestation), which may be attributed to lack of improper environmental protection strategy in place in the metropolis. The study demonstrates the potentialities of remote sensing and GIS in assessing urban growth and its impacts on deforestation. The outcome of the study can serve as input into a relationship model for predicting the impact of urban growth on deforestation

Series Solution of the Multispecies Lotka-Volterra Equations by Means of the Homotopy Analysis Method

The time evolution of the multispecies Lotka-Volterra system is investigated by the homotopy analysis method (HAM). The continuous solution for the nonlinear system is given, which provides a convenient and straightforward approach to calculate the dynamics of the system. The HAM continuous solution generated by polynomial base functions is of comparable accuracy to the purely numerical fourth-order Runge-Kutta method. The convergence theorem for the three-dimensional case is also given

Targeting of the Year One dental visit for United States children

Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/75098/1/j.1365-263X.2003.04602.x.pd

Satellite-based characterization of climatic conditions before large-scale general flowering events in Peninsular Malaysia

General flowering (GF) is a unique phenomenon wherein, at irregular intervals, taxonomically diverse trees in Southeast Asian dipterocarp forests synchronize their reproduction at the community level. Triggers of GF, including drought and low minimum temperatures a few months previously has been limitedly observed across large regional scales due to lack of meteorological stations. Here, we aim to identify the climatic conditions that trigger large-scale GF in Peninsular Malaysia using satellite sensors, Tropical Rainfall Measuring Mission (TRMM) and Moderate Resolution Imaging Spectroradiometer (MODIS), to evaluate the climatic conditions of focal forests. We observed antecedent drought, low temperature and high photosynthetic radiation conditions before large-scale GF events, suggesting that large-scale GF events could be triggered by these factors. In contrast, we found higher-magnitude GF in forests where lower precipitation preceded large-scale GF events. GF magnitude was also negatively influenced by land surface temperature (LST) for a large-scale GF event. Therefore, we suggest that spatial extent of drought may be related to that of GF forests, and that the spatial pattern of LST may be related to that of GF occurrence. With significant new findings and other results that were consistent with previous research we clarified complicated environmental correlates with the GF phenomenon

The Characterization of J-Integral for Elastic-Plastic Crack Growth Evaluation using Finite Element Analysis

J-integral is a fracture mechanic parameter that can be used to characterize elastic-plastic fracture mechanic (EPFM) behavior. The path independent characteristic in J-integral is proposed by Rice [1], and it is widely used in a lot of research. Another approach is the load-displacement approach, where the J-integral is calculated by the area under the load-displacement curve. However, the validity of the J-integral value by load-displacement approach is yet to be confirmed. This paper is aimed to investigate the effect of crack length ratio of CT specimen to J-integral value by two approaches: path-integral approach and load-displacement approach. Finite element analysis of compact tension (CT) model with crack length ratio a/W between 0.2 to 0.5 was carried out under displacement δ between 0.2 to 1.0 mm using ANSYS parametric design language (APDL). The J value by path integral approach, Jpath is compared to the value calculated from load-displacement approach, Jp-d. It was found that path independency occurs for J value evaluated from path integral approach. A correction factor needs to be introduced since the load-displacement approach cannot be used for shallow crack cases

The Serological Findings of Parvo virus B19 and Neopterin Detection among Sickle cell Disease Patients and Blood Doners in the Kingdom of Bahrain

Introduction. Parvovirus B19 (PV B19) is a small, non-enveloped, ss DNA virus with an icosahedral capsid having a size of 18–26 nm. PV B19 transmits through respiratory droplets, blood transfusion and nosocomial infections that have also been documented recently. The virus targets the actively dividing Erythroid Progenitor Cells (EPCs) that are found in the human bone marrow, fetal liver and human umbilical cord. Methods. The study was particularly conducted on Sickle Cell Disease (SCD) patients and focuses on the determination of parvovirus B19 among Bahraini population by relying on their clinical status. The serological study of PV B19 was performed using Enzyme Linked Immunosorbent Assay (ELISA) technique and includes 150 SCD patientsand 100 healthy blood donors in which both males and females were employed. The samples were taken from the emergency unit of Salmania Medical Complex (SMC) and Ibrahim Khalil Kano Center (IKKC). Results. Of the 150 SCD patients, 100 were with vaso-occlusive crisis(VOC) and 50 non-vaso-occlusive crisis (NVOC). The three groups showed significantly higher percentages of PV B19 IgG but the percentage in SCD was relatively high compared to the control group of age-matched healthy donors – 70% of the VOC patients, 76% of the NVOC cases and 57% of blood donors were found to be IgG sero-positive. Discussion and Conclusion. PV B19 is a pathogenic virus and sometimes considered as life-threatening specifically for those individuals who have SCD due to which a risk of transient aplastic crisis increases. This virus is only associated with those patients whohave some hematological disorders such as hemolytic anemia and erythro-cytopenia. An effective screening test must be performed in the future to reduce the risk of PV B19 infection. Keywords: Aplastic Crisis, Seroprevalence, Bahraini Population, Genotypes, Vasoocclusive crisis, Neopteri