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In Vitro Antileishmanial Activity of Bombax Ceiba Linn. Flowers
(2011) Basukala, Om; Keishna Das Manandhar
Visceral leishmaniasis (VL) is one of the neglected tropical diseases, as many as 8 million people in the 13 endemic districts of Nepal. Incidence of VL is associated with poverty and is further pushing the poor to the poorest. Available treatment options are limited and unsatisfactory due to several limitations like parenteral administration, long course of treatment, toxic side effects and high treatment cost. Malnutrition and co-infection with diseases such as malaria, pneumonia, HIV and development of drug-resistance by parasites are further worsening the situation. In absence of a vaccine there is an urgent need of alternative treatments. One of the main sources for new antileishmanial agents are secondary metabolites isolated from plants. Nepal is rich in natural products biodiversity and habitats more than 900 types of valuable medicinal plants among 7000 medicinal plants found all over the world. However, these natural resource has largely been unexplored for its medicinal and therapeutic potential against leishmaniasis. Flowers of Bombax ceiba has been known for its several enthnomedicinal uses in various afflictions including splenomegaly, a hallmark of VL. To evaluate its potential use in VL an in vitro antileishmanial activity of the flowers of the plant was carried out. The crude ethanolic extract of the flower inhibited promastigote growth at IC 50 of 131.24 ± 12.54 µg/mL. The methanol fraction showed a greater inhibitory effect against promastigotes (IC 50 of 89.62 ± 0.55 µg/mL) and amastogotes (IC 50 of 58.73 ± 1.89 µg/mL) than the other fractions. Fraction n-hexane, also had appreciable inhibitory activity against promastigotes (105.12 ± 7.99 µg/mL) and amastigotes (61.39 ± 1.34 µg/mL), indicating the active compounds might have been attributed to these fractions. The reference drug miltefosine had lower 50% inhibitory concentration values for both forms of the parasite (IC 50 for promastigote: 11.27 ± 0.52 µg/mL and IC 50 for amastiogote: 4.12 ± 0.13 µg/mL) than any of the fractions or the crude extract. From the dose response curves and time dependent efficacy response graphs it can be conferred that n-hexane and methanol fractions are leishmanicidal and acetone and chloroform fractions are leishmanistatic. Also, hexane fraction was effective at low dose against promastigotes (IC 100 at 250 µg/mL) and so was methanol fraction against amastigotes (IC 100 at 125 µg/mL). Cytotoxicity test revealed the components were safe, with selectivity indices values greater than 1. Moreover, methanol fraction of the crude flower extract was found similar in activity of miltefosine when compared to at its CC50 concentration (P=0.0638). Identification of the effective compounds from methanol and n-hexane fractions could lead to discovery of lead compounds effective against kala-azar. To the best of our knowledge this is the first report to demonstrate antileishmanial activity of B. ceiba Linn. flowers. This work also focuses on the need of screening of medicinal plants native to Nepal for anti-leishmanial activity. Key words: Visceral leishmaniasis, Leishmania donovani, Bombax ceiba, Semal, IC50, In vitro, antileishmanial acitivity.
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Epidemiological, serological immunological and molecular profiles of hepatitis B virus (HBV) IN Nepal
(2018) Shrestha, Smita; Krishna Das Manandhar
Hepatitis B virus (HBV) is a common cause of liver disease and hepatocellular carcinoma. The most common route of transmission being spreading through the blood transfusion and organ transplants. It infects more than 350 million people worldwide. It is estimated that 260,000 individuals are chronically infected with HBV in Nepal and majority of them are unaware of their infection. In this study, epidemiological study was conducted by direct interviewing with all suspectedpatients. The serological study for different antigens and antibody was conducted by Rapid Diagnostic strip test (RDT). Enzymes Linked Immunosorbent Assay (ELISA) was used to confirm this test. Moreover, the molecular test was done by using Real Time PCR for the quantification and genotyping of HBV. Sequence analysis was done by using Sequence analysis software V 5.2 and phylogenetic tree was constructed by neighbor joining method. A total of 500 Nepalese suspected HBV patients were enrolled where 64 % (n=320) werefound to be HBV positive and 36 % (n=180) were HBV negative. This study was donebased on the HBsAg positivity. HBV infection was higher in males (n=213) as comparedwith female (n=106) with male and female ratio of 2.01:1. The most productive agegroups of 20-40 years followed by 40-60 years were found to be associated with the hepatitis B infection. The sero-prevalence rate was higher in province 2 followed by province 3. All the samples recorded positive for HBsAg from ELISA were assayed for Liver function tests (LFT). The level of total bilirubin was found higher in 25.31 % (n=81) patients indicating liver damage. However,the result obtained from the estimation of ALT in HBsAg positivecases showed that 54.69 % (n=197) have elevated level of ALT indicating that these samples seem to have carrier state of the infection. Thrombocytopenia is a common feature of chronic liver disease and was reported in 0.94 % (n=3) of total HBV infected patients.The viral load was found to be highest in chronic HBV patients with HBeAg positive. Genotype D was found to be common among the Nepalese population. HBV sub- genotypes A1,C1,D1,CDand D4 were detected in samples after sequence analysis. Phylogenetic tree showed that genotype-A1 was very closely related to isolates from France and Belgium,Genotype-C1 from Japan,Genotype-D1& D4 from India.CD-recombinant genotype indicated probable divergence of Genotype C to Genotype D or recombinant event might have occurred in S-gene as S-gene determines Genotype. Key Words: Hepatitis B virus (HBV), seroprevalence, LFT, Genotype, Viral load, DNA.
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Genome- Wide Identification of Auxin Response factor ( ARF) Genes and Expression analysis in Capsicum Fruits
(2018) Sunuwar, Bidyakala; Rajani Malla
One of the important plant transcription factors is Auxin Response Factor (ARF), which has vital role in regulation of growth and development of the plants, and stress tolerance. ARFs key regulator is the phyto-hormone Auxin. Very less investigation has been done about ARF family of pepper (Capsicum annuum) and their roles in biological processes. From the available updated genome database, 28 ARF genes were identified in pepper genome and 24 of them are distributed on 12 different chromosome and 4 are found to be pseudogenes. A phylogenetic tree was constructed depending on ARFs sequences derived from Pepper, Tomato, Arabidopsis, Potato and Rice and Simple Sequence Repeats (SSRs) were identified present in Capsicum ARF. In this study, expression of selected 12 ARF genes in fruits (developmental stage: early, breaker and mature) of two distinct Capsicum species (Capsicum annuum and Capsicum chinense) were analyzed in transcriptome level. Confirmation of expression analysis was done by quantitative real time PCR (qRTPCR). The preliminary results of our experiment elucidates, ARF plays significant role in fruit development of pepper. This result will provide for identifying proper function and molecular breeding studies of ARF genes in pepper in forthcomingdays. Keywords: Transcription factor, plant hormone, transcriptome, quantitative real time PCR (qRT-PCR), molecular breeding