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991.
Mohammad Arif Ashraf Achia Khatun Tanzila Sharmin Faraid Mobin Arifur Rahman Tanu Toufique Morshed Tawkir Ahmad Fakir Rifat Ara Begum AHM Nurun Nabi 《Bioinformation》2014,10(6):384-386
The term of medicinal plants include a various types of plants used in herbalism with medicinal activities. These plants are
considered as rich resources of ingredients which can be used as complementary and alternative medicines and, also in drug
developments and synthesis. In addition, some plants regarded as valuable origin of nutrition. Thus, all these plants are
recommended as therapeutic agents. Information related to medicinal plants and herbal drugs accumulated over the ages are
scattered and unstructured which make it prudent to develop a curated database for medicinal plants. MPDB 1.0 database is
dedicated to provide the first window to find the plants around Bangladesh claimed to have medicinal and/or nutritive values by
accumulating data from the published literatures. This database contains 406 medicinal plants with their corresponding scientific,
family and local names as well as utilized parts for treatment from different districts of Bangladesh. Information regarding
ailments is available for 353 plants. In addition, we have found active compounds for 78 plants with their corresponding PubMed
ID.
Availability
www.medicinalplantbd.net 相似文献992.
Silent information regulator type-1 (SIRT1) is the best-studied member of the Sirtuin (Sir2) family of nicotinamide dinucleotide (NAD)-dependent class III histone deacetylases (HDACs), but has not yet been explored in cutaneous T-cell lymphoma (CTCL). We analyzed five CTCL cell lines and lesional tissues using flow cytometry, immunostaining, immunoblotting, cell death, viability, and apoptosis assays, small-molecule inhibitors, and shRNA knockdown. We found strong SIRT1 expression among CTCL lines relative to normal lymphocytes. CTCL cells in lesional tissues also expressed SIRT1 strongly. SIRT1 knockdown resulted in reduced cellular metabolism and proliferation, increased apoptosis, and PARP cleavage products. Tenovin-1, which reversibly inhibits class III HDACs (SIRT1 and SIRT2), reduced SIRT enzymatic activity and SIRT1 expression and led to increased apoptosis. These alterations were accompanied by increased forkhead box O3 (FoxO3) in several cell lines and increased nuclear p53, as well as acetylated p53 in wtp53 MyLa CTCL line. A combination of class I/II and class III HDACIs (vorinostat and tenovin-1) produced significantly greater growth inhibition, cell death via apoptosis, as well as superior p53 promoter upregulation in wtp53 MyLa cells as compared with either agent alone. This occurred in a partially p53-dependent manner, as these effects were blunted by p53 knockdown. Our results indicate that SIRT1 is strongly expressed in CTCL. Its inhibition results in reduced growth and increased apoptosis of CTCL cells. Furthermore, our findings suggest that some CTCL patients, such as those with wtp53, might benefit more from treatment with a combination of different classes of HDACIs than with a single agent. 相似文献
993.
Cell-Autonomous Progeroid Changes in Conditional Mouse Models for Repair Endonuclease XPG Deficiency
Sander Barnhoorn Lieneke M. Uittenboogaard Dick Jaarsma Wilbert P. Vermeij Maria Tresini Michael Weymaere Hervé Menoni Renata M. C. Brandt Monique C. de Waard Sander M. Botter Altaf H. Sarker Nicolaas G. J. Jaspers Gijsbertus T. J. van der Horst Priscilla K. Cooper Jan H. J. Hoeijmakers Ingrid van der Pluijm 《PLoS genetics》2014,10(10)
As part of the Nucleotide Excision Repair (NER) process, the endonuclease XPG is involved in repair of helix-distorting DNA lesions, but the protein has also been implicated in several other DNA repair systems, complicating genotype-phenotype relationship in XPG patients. Defects in XPG can cause either the cancer-prone condition xeroderma pigmentosum (XP) alone, or XP combined with the severe neurodevelopmental disorder Cockayne Syndrome (CS), or the infantile lethal cerebro-oculo-facio-skeletal (COFS) syndrome, characterized by dramatic growth failure, progressive neurodevelopmental abnormalities and greatly reduced life expectancy. Here, we present a novel (conditional) Xpg−/− mouse model which -in a C57BL6/FVB F1 hybrid genetic background- displays many progeroid features, including cessation of growth, loss of subcutaneous fat, kyphosis, osteoporosis, retinal photoreceptor loss, liver aging, extensive neurodegeneration, and a short lifespan of 4–5 months. We show that deletion of XPG specifically in the liver reproduces the progeroid features in the liver, yet abolishes the effect on growth or lifespan. In addition, specific XPG deletion in neurons and glia of the forebrain creates a progressive neurodegenerative phenotype that shows many characteristics of human XPG deficiency. Our findings therefore exclude that both the liver as well as the neurological phenotype are a secondary consequence of derailment in other cell types, organs or tissues (e.g. vascular abnormalities) and support a cell-autonomous origin caused by the DNA repair defect itself. In addition they allow the dissection of the complex aging process in tissue- and cell-type-specific components. Moreover, our data highlight the critical importance of genetic background in mouse aging studies, establish the Xpg−/− mouse as a valid model for the severe form of human XPG patients and segmental accelerated aging, and strengthen the link between DNA damage and aging. 相似文献
994.
Adnan Daud Khan Sultan Daud Khan Rehan Ullah Khan Naveed Ahmad 《Plasmonics (Norwell, Mass.)》2014,9(2):461-475
The presence of plasmonic Fano-like resonances in the optical response of isolated and dimer metal-dielectric-metal nanostructures are investigated theoretically. The nanostructures are engineered in such a way to support multiple Fano-like resonances that are induced by the interference of bright and dark plasmon modes. It is found that the dimer resonators exhibit different types of Fano resonances for both the transverse and longitudinal polarizations unlike conventional nanodimers. Several configurations of the dimer Fano resonator are analyzed with special emphasis on the Fano spectral line shape. Breaking the symmetry of the dimer nanostructure in various directions control the asymmetric line shape and provides different kinds of unique Fano resonances. In certain cases, the Fano resonators exhibit multiple Fano resonances that are particularly significant for plasmon line shaping and can serve as platforms for multi-wavelength sensing applications. 相似文献
995.
Nisar Ahmad Bilal Haider Abbasi Hina Fazal Mubarak Ali Khan Muhammad Siddique Afridi 《Comptes rendus biologies》2014,337(1):19-28
In this study, a novel approach for in vitro regeneration of Piper nigrum L. has been applied in order to increase healthy biomass, phytochemicals and piperine production via reverse photoperiod (16hD/8hL). Leaf portions of the seed-derived plants were placed on an MS-medium fortified with different PGRs. Under 16hD/8hL, thidiazuron (TDZ; 4.0 mg L−1) and BA (1.5 mg L−1) was found to be the most effective (< 90%) in callus induction. Two concentrations (1.5, 2.0 mg L−1) of the IBA produced > 80% shoots from callus cultures. Healthy shoots were transferred to rooting medium and higher percentage of rooting (< 90%) was observed on IBA (1.5 mg L−1). These in vitro tissues were subjected to amino acid analysis, spectrophotometry, and HPLC. ARG, SER, THR, and TYR were the most abundant components out of 17 amino acids. Higher amino acid production was observed under normal photoperiod (16hL/8hD) than under reverse photoperiod (16hD/8hL). The highest total phenolic content (TPC; 9.91 mg/g-DW) and flavonoid content (7.38 mg/g-DW) were observed in callus cultures incubated under 16hL/8hD than other tissues incubated under 16hD/8hL photoperiod. Higher DPPH and PoMo activities were observed in tissues incubated under 16hL/8hD photoperiod, while ABTS and Fe2+ chelating activities were found higher in tissues incubated under reverse photoperiod. Significant quantities of piperine content were observed in all tissues except callus cultures. These results suggest that reverse photoperiod is a promising approach for callus induction, phytochemicals and piperine production for commercial applications. 相似文献
996.
997.
The information and communication technology (ICT) sector has grown exponentially in the recent years. An essential component of the ICT organizations is constituted by the data centers that are densely populated with redundant servers and communicational links to ensure the provision of 99.99 % availability of services; a fact responsible for the heavy energy consumption by data centers. For energy economy, the redundant elements can be powered off based on the current workload within the data center. We propose a Data Center-wide Energy-Efficient Resource Scheduling framework (DCEERS) that schedules data center resources according to the current workload of the data center. Minimum subset of resources to service the current workload are calculated by solving the Minimum Cost Multi Commodity Flow (MCMCF) using the Benders decomposition algorithm. The Benders decomposition algorithm is scalable: it solves the MCMCF problem in linear time for large data center environments. Our simulated results depict that DCEERS achieves better energy efficiency than the previous data center resource scheduling methodologies. 相似文献
998.
A variant of KCC2 from patients with febrile seizures impairs neuronal Cl− extrusion and dendritic spine formation
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Martin Puskarjov Patricia Seja Sarah E Heron Tristiana C Williams Faraz Ahmad Xenia Iona Karen L Oliver Bronwyn E Grinton Laszlo Vutskits Ingrid E Scheffer Steven Petrou Peter Blaesse Leanne M Dibbens Samuel F Berkovic Kai Kaila 《EMBO reports》2014,15(6):723-729
Genetic variation in SLC12A5 which encodes KCC2, the neuron-specific cation-chloride cotransporter that is essential for hyperpolarizing GABAergic signaling and formation of cortical dendritic spines, has not been reported in human disease. Screening of SLC12A5 revealed a co-segregating variant (KCC2-R952H) in an Australian family with febrile seizures. We show that KCC2-R952H reduces neuronal Cl− extrusion and has a compromised ability to induce dendritic spines in vivo and in vitro. Biochemical analyses indicate a reduced surface expression of KCC2-R952H which likely contributes to the functional deficits. Our data suggest that KCC2-R952H is a bona fide susceptibility variant for febrile seizures. 相似文献
999.
Iqbal Ahmad Kiran Qadeer Saima Zahid Muhammad Ali Sheraz Tehmina Ismail Waqar Hussain Izhar Ahmad Ansari 《AAPS PharmSciTech》2014,15(5):1324-1333
The degradation kinetics of 5 × 10−5 M cyanocobalamin (B12) and hydroxocobalamin (B12b) in the presence of ascorbic acid (AH2) was studied in the pH range of 1.0–8.0. B12 is degraded to B12b which undergoes oxidation to corrin ring cleavage products. B12b alone is directly oxidized to the ring cleavage products. B12 and B12b in degraded solutions were simultaneously assayed by a two-component spectrometric method at 525 and 550 nm without interference from AH2. Both degrade by first-order kinetics and the values of the rate constants at pH 1.0–8.0 range from 0.08 to 1.05 × 10−5 s−1 and 0.22–7.62 × 10−5 s−1, respectively, in the presence of 0.25 × 10−3 M AH2. The t1/2 values of B12 and B12b range from 13.7 to 137.5 h and 2.5–87.5 h, respectively. The second-order rate constants for the interaction of AH2 with B12 and B12b are 0.05–0.28 × 10−2 and 1.10–30.08 × 10−2 M−1 s−1, respectively, indicating a greater effect of AH2 on B12b compared to that of B12. The kobs–pH profiles for both B12 and B12b show the highest rates of degradation around pH 5. The degradation of B12 and B12b by AH2 is affected by the catalytic effect of phosphate ions on the oxidation of AH2 in the pH range 6.0–8.0.KEY WORDS: ascorbic acid, cyanocobalamin, degradation, hydroxocobalamin, kinetics, two-component spectrometry 相似文献
1000.
Nazirah G Mohamed Nurdiana Z Abidin Kim S Law Mika Abe Megumi Suzuki Ahmad M Che Muhamed Rabindarjeet Singh 《Journal of physiological anthropology》2014,33(1):28