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991.
Andrographis paniculata (Burm.f) Nees is one of the most popular and important medicinal plant of the Orient, and South East Asia. It finds mention
in various forms in Indian, Chinese, Malay, Thai, Unani, and Japanese systems of medicine. The plant exhibits anti-cancer,
anti-inflammatory, anti-diabetic, anti-hypertensive, anti-venom, cholestatic, hepatoprotective, anti-thrombotic, anti-retroviral,
anti-microbial, anti-pyretic, anti-malarial, anti-oxidant, immunomodulatory, and cardioprotective effects. The major active
principles contributing to biological activity are diterpene lactones, but flavonoids, xanthones and caffeic acid derivatives
also contribute to anti-oxidant, anti-proliferative, anti-atherosclerotic, and anti-malarial effects. As a result of its wide
spectrum of pharmacological activity, almost impeccable safety profile, being a widely cultivated medicinal plant, we have
collected and compiled various facets of this plant. Extensive datamining of the phytochemistry and pharmacology of Andrographis paniculata revealed more than 50 diterpene lactones, 30 flavonoids, 8 quinic acid derivatives, and 4 xanthones. This review contains
information on around 80 isolated compounds, out of which more than half of the compounds have no reported pharmacological
activity. Though there are some good reviews available on Andrographis paniculata, the authors of the earlier reviews focused on one or two aspects of the plant and none have attempted to integrate the available
information on this plant. This provided us the much needed impetus, warranting a full-fledged and complete review on Andrographis paniculata, one of the most popular and important Oriental medicinal plant. 相似文献
992.
Omar bin Shawkataly Chin-Ping Goh Abu Tariq Imthyaz Ahmad Khan Hoong-Kun Fun Mohd Mustaqim Rosli 《PloS one》2015,10(3)
A series of complexes of the type LAuCl where L = tris(p-tolylarsane), tris(m-tolylarsane), bis(diphenylarsano)ethane, and tris(naphthyl)arsane have been synthesized. All of the new complexes, 1-4, have been fully characterized by means of 1H NMR and 13C NMR spectroscopy and single crystal X-ray crystallography. The structures of complexes 1-4 have been determined from X-ray diffraction data. The linear molecules have an average bond distance between gold-arsenic and gold-chlorine of 2.3390Å and 2.2846Å, respectively. Aurophilic interaction was prominent in complex 1 and 3, whereas complex 2 and 4 do not show any such interaction. The intermolecular gold interaction bond length was affected by the electronegativity of the molecule. The computed values calculated at DFT level using B3LYP function are in good agreement with the experimental results. 相似文献
993.
Ali M. Humada Mojgan Hojabri Mohd Herwan Bin Sulaiman Hussein M. Hamada Mushtaq N. Ahmed 《PloS one》2016,11(4)
A grid-connected photovoltaic (PV) system operates under fluctuated weather condition has been modeled and characterized based on specific test bed. A mathematical model of a small-scale PV system has been developed mainly for residential usage, and the potential results have been simulated. The proposed PV model based on three PV parameters, which are the photocurrent, IL, the reverse diode saturation current, Io, the ideality factor of diode, n. Accuracy of the proposed model and its parameters evaluated based on different benchmarks. The results showed that the proposed model fitting the experimental results with high accuracy compare to the other models, as well as the I-V characteristic curve. The results of this study can be considered valuable in terms of the installation of a grid-connected PV system in fluctuated climatic conditions. 相似文献
994.
Hadi Zokaeifar Nahid Babaei Che Roos Saad Mohd Salleh Kamarudin Kamaruzaman Sijam 《Biocontrol Science and Technology》2014,24(2):233-240
Two Bacillus subtilis strains L10 and G1, previously isolated from fermented pickles, were tested for antibacterial activity against Vibrio harveyi using a well-diffusion agar assay. Antibiotic biosynthesis genes were then detected in both bacterial strains and included the following genes: bacA, bacB and bacD genes for bacilysin production, ppsE/fenB gene for plipastatin/fengycin production, albF and albA genes for subtilosin production, and srfAB and sfP genes for surfactin production. Based on these results, two B. subtilis strains could be considered as potential biological control agents in aquaculture. 相似文献
995.
996.
Navarro-Muñoz Jorge C. de Jong Auke W. Gerrits van den Ende Bert Haas Pieter-Jan Then Euníce R. Mohd Tap Ratna Collemare Jérôme Hagen Ferry 《Mycopathologia》2019,184(6):731-734
Mycopathologia - Candida vulturna is a new member of the Candida haemulonii species complex that recently received much attention as it includes the emerging multidrug-resistant pathogen Candida... 相似文献
997.
Damini Singh Amit Rahi Romika Kumari Vatika Gupta Gunjan Gautam Somya Aggarwal Mohd Rehan Rakesh Bhatnagar 《Journal of cellular biochemistry》2019,120(7):11318-11330
The role of TatD DNases as DNA repair enzymes or cell death (apoptotic) nucleases is well established in prokaryotes as well as eukaryotes. The current study aims to characterize the TatD nuclease from Bacillus anthracis (Ba TatD) and to explore its key histidine catalytic residues. Ba TatD was found to be a metal-dependent, nonspecific endonuclease which could efficiently cleave double-stranded DNA substrates. Moreover, Ba TatD nuclease was observed to be thermostable up to 55°C and act in a wide pH range indicating its industrial applicability. Diethyl pyrocarbonate-based histidine-selective alkylation of the Ba TatD resulted in a loss of its nuclease activity suggesting a crucial role of the histidine residues in its activity. The key residues of Ba TatD were predicted using sequence analysis and structure-based approaches, and then the predicted residues were further tested by mutational analysis. Upon mutational analysis, H128 and H153 have been found to be crucial for Ba TatD activity, though H153 seems to bear an important but a dispensable role for the Ba TatD nuclease. Ba TatD had a uniform expression in the cytosol of B. anthracis, which indicates a significant role of the protein in the pathogen's life cycle. This is the first study to identify and characterize the TatD DNase from B. anthracis and will be helpful in gaining more insights on the role of TatD proteins in Gram-positive bacteria where it remains unexplored. 相似文献
998.
999.
Marc Rhainds Gerhard Gries Mohd. Mat Min 《Entomologia Experimentalis et Applicata》1999,91(3):375-383
A study conducted in a Malaysian plantation of oil palm over 5 consecutive generations of bagworms, Metisa plana (Walker) (Lepidoptera: Psychidae), evaluated extent and causes of variability for 3 components of reproductive success: pupal mortality, mating success and fecundity. The population of M. plana in the experimental site exhibited cycles of 70–80 days with discrete generations. Females emerged before males during all generations. Relatively large proportions of M. plana did not reproduce, either because they did not survive as pupa or (for females) mate as adult. Occurrence of unmated female bagworms may be attributed to complex mating procedure, short lifespan of females, limited mating capacity of males, protogyny inducing female-biased operational sex-ratio, and/or flightlessness per se constraining mating success of females. Size attained at pupation is a significant component of reproductive success, with large individuals having greatest survival during pupal stage, mating success and fecundity. Population density also influenced reproductive success of M. plana: female and (to a lesser extent) male larvae on crowded palms attained small size at pupation; survival of pupae was density-dependent during 2 generations for females and density-independent during 5 generations for males; mating success of females was inverse density-dependent during 4 generations. Size- and density-dependent mating success of females may be attributed to mate choice by males, size-dependent pheromone production by and longevity of females, and/or disorientation of mate-seeking males around heavily infested palms. Long-term studies are needed to determine whether and to what extent attributes of oil palm, seasonal fluctuations of abiotic factors and inter-generational variations of reproductive success influence population dynamics of M. plana. 相似文献
1000.
Mohammad J. Al-Yamani Syed Mohammed Basheeruddin Asdaq Abdulhakeem S. Alamri Walaa F. Alsanie Majid Alhomrani Abdulkhaliq J. Alsalman Mohammed Al mohaini Maitham A. Al Hawaj Amani A. Alanazi Khulud D. Alanzi Mohd. Imran 《Saudi Journal of Biological Sciences》2022,29(1):11-17
Background and objectiveAlthough, the anti-depressant like effects of apigenin (APG) are documented in the literature, the underlying mechanism for exerting such an effect is still not clear. In this research, an attempt was made to determine the possible role of APG for antidepressant activity through serotonergic and catecholaminergic systems using standardized animal models.Materials and methodsThe antidepressant property of APG was determine by involving tail suspension (TST) and modified forced swimming tests (MFST). The effect of APG was evaluated at 25 and 50 mg/kg. In mechanistic models, animals were pretreated with catecholaminergic and serotonergic antagonists prior to administration of APG. The results obtained were statistically analyzed to determine the level of significance.ResultsThe period of immobility in both models (TST and MFST) was significantly reduced by APG (25 and 50 mg/kg). The best therapetuic dose of APG (50 mg/kg) was selected for the mechanistic study. The anti-immobility effect of APG declined to a significant extent upon pretreatment with catecholaminergic antagonists (α-methyl-para-tyrosine methyl ester; SCH 23390; sulpiride; phentolamine) and serotonergic inhibitors (p-clorophenylalanine-methyl-ester; ondansetron) in both TST and MFST models. The antidepressant benefits of apigenin were only modestly reversed when rats were given propranolol.ConclusionsThe findings suggest that APG's antidepressant effect is mediated by the α-adrenergic, dopaminergic and 5-HT3 serotonergic receptors. 相似文献