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311.
Muhammad Sajjad Haider Waseem Ashraf Sana Javaid Muhammad Fawad Rasool Hafiz Muhammad Abdur Rahman Hammad Saleem Syed Muhammad Muneeb Anjum Farhan Siddique Alejandro Morales-Bayuelo Savas Kaya Faleh Alqahtani Fawaz Alasmari Imran Imran 《Saudi Journal of Biological Sciences》2021,28(8):4384-4398
In the current study, we investigated the phytochemical and neuropharmacological potential of Indigofera sessiliflora, an indigenous least characterized plant widely distributed in deserted areas of Pakistan. The crude extract of the whole plant Indigofera sessiliflora (IS.CR) was preliminary tested in-vitro for the existence of polyphenol content, antioxidant and anticholinesterase potential followed by detailed chemical characterization through UHPLC-MS. Rats administered with different doses of IS.CR (100–300 mg/kg) for the duration of 4-weeks were behaviorally tested for anxiety and cognition followed by biochemical evaluation of dissected brain. The in-silico studies were employed to predict the blood–brain barrier crossing tendencies of secondary metabolites with the elucidation of the target binding site. The in-vitro assays revealed ample phenols and flavonoids content in IS.CR with adequate anti-oxidant and anticholinesterase potential. The dose-dependent anxiolytic potential of IS.CR was demonstrated in open field (OFT), light/dark (L/D) and elevated plus maze (EPM) tests as animals spent more time in open, illuminated and elevated zones (P < 0.05). In the behavioral tests for learning/memory, the IS.CR reversed the scopolamine-induced cognitive deficits, as animals showed better (P < 0.05) spontaneous alternation and discrimination index in y-maze and novel object recognition (NOR) tests. Similarly, as compared to amnesic rats, the step-through latencies were increased (P < 0.05) and escape latencies were decreased (P < 0.05) in passive avoidance (PAT) and Morris water maze (MWM) tests, respectively. Biochemical analysis of rat brains showed significant reduction in malondialdehyde and acetylcholinesterase levels, alongwith preservation of glutathione peroxidase and superoxide dismutase activity. The docking studies further portrayed a possible interaction of detected phytoconstituents with acetylcholinesterase target. The results of the study show valuable therapeutic potential of phytoconstituents present in IS.CR to correct the neurological disarrays which might be through antioxidant activity or via modulation of GABAergic and cholinergic systems by artocommunol, 1,9-dideoxyforskolin and 6E,9E-octadecadienoic acid. 相似文献
312.
Tim Downing David J. Lynn Sarah Connell Andrew T. Lloyd AK Fazlul Haque Bhuiyan Pradeepa Silva Arifa N. Naqvi Rahamame Sanfo Racine-Samba Sow Baitsi Podisi Cliona O’Farrelly Olivier Hanotte Daniel G. Bradley 《Immunogenetics》2009,61(4):303-314
There have been significant evolutionary pressures on the chicken during both its speciation and its subsequent domestication
by man. Infectious diseases are expected to have exerted strong selective pressures during these processes. Consequently,
it is likely that genes associated with disease susceptibility or resistance have been subject to some form of selection.
Two genes involved in the immune response (interferon-γ and interleukin 1-β) were selected for sequencing in diverse chicken
populations from Pakistan, Sri Lanka, Bangladesh, Kenya, Senegal, Burkina Faso and Botswana, as well as six outgroup samples
(grey, green, red and Ceylon jungle fowl and grey francolin and bamboo partridge). Haplotype frequencies, tests of neutrality,
summary statistics, coalescent simulations and phylogenetic analysis by maximum likelihood were used to determine the population
genetic characteristics of the genes. Networks indicate that these chicken genes are most closely related to the red jungle
fowl. Interferon-γ had lower diversity and considerable coding sequence conservation, which is consistent with its function
as a key inflammatory cytokine of the immune response. In contrast, the pleiotropic cytokine interleukin 1-β had higher diversity
and showed signals of balancing selection moderated by recombination, yielding high numbers of diverse alleles, possibly reflecting
broader functionality and potential roles in more diseases in different environments.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users.
An erratum to this article can be found at 相似文献
313.
Molecular cloning and characterization of an alpha1,3 fucosyltransferase, CEFT-1, from Caenorhabditis elegans 总被引:1,自引:1,他引:1
We report on the identification, molecular cloning, and characterization of
an alpha1,3 fucosyltransferase (alpha1,3FT) expressed by the nematode,
Caenorhabditis elegans . Although C. elegans glycoconjugates do not express
the Lewis x antigen Galbeta1-- >4[Fucalpha1-->3]GlcNAcbeta-->R,
detergent extracts of adult C.elegans contain an alpha1,3FT that can
fucosylate both nonsialylated and sialylated acceptor glycans to generate
the Lexand sialyl Lexantigens, as well as the lacdiNAc-containing acceptor
GalNAcbeta1-->4GlcNAcbeta1-- >R to generate GalNAcbeta1-->4
[Fucalpha1-->3]GlcNAcbeta1-->R. A search of the C.elegans genome
database revealed the existence of a gene with 20-23% overall identity to
all five cloned human alpha1,3FTs. The putative cDNA for the C.elegans
alpha1,3FT (CEFT-1) was amplified by PCR from a cDNA lambdaZAP library,
cloned, and sequenced. COS7 cells transiently transfected with cDNA
encoding CEFT-1 express the Lex, but not sLexantigen. The CEFT-1 in the
transfected cell extracts can synthesize Lex, but not sialyl Lex, using
exogenous acceptors. A second fucosyltransferase activity was detected in
extracts of C. elegans that transfers Fuc in alpha1,2 linkage to Gal
specifically on type-1 chains. The discovery of alpha-fucosyltransferases
in C. elegans opens the possibility of using this well-characterized
nematode as a model system for studying the role of fucosylated glycans in
the development and survival of C.elegans and possibly other helminths.
相似文献
314.
Dagmar Szakasits Shahid Siddique Holger Bohlmann 《Plant Molecular Biology Reporter》2007,25(3-4):115-120
We report a new and improved pPZP vector (pPZP3425) for efficient plant transformation. This vector is derived from the widely
used pPZP100 series of binary Agrobacterium vectors. One disadvantage of these vectors is the use of chloramphenicol resistance for selection in Escherichia coli and Agrobacteria. We have therefore included a kanamycin resistance gene for selection in Agrobacterium. Furthermore, the strong 35S CaMV promoter driving the plant resistance gene has been replaced by the weaker nos promoter because it has been shown that the 35S promoter driving the plant resistance marker can lead to ectopic expression
of the transgene. During replacement of the 35S promoter, the NcoI site within the plant resistance gene has been removed,
and NcoI can now be used for cloning purposes within the expression cassette which consists of an intron-containing gus gene driven by a strong constitutive promoter (35S promoter with doubled enhancer plus omega-element as translational enhancer).
Thus, a single vector can conveniently be used for two purposes: (1) for overexpression of proteins by replacing the gus gene by the coding sequence of choice and (2) for creation of promoter:gus fusions by substituting the constitutive promoter by any other promoter. We demonstrate the usefulness of this vector for
cloning a promoter:gus fusion and in planta transformation of Arabidopsis. 相似文献
315.
全球气候变暖对干旱农业生态系统管理提出了严峻的挑战,解决方案须从个体到全球不同尺度开展系统研究,并协同考虑与社会经济系统的互作机制。综述了2010年7月24日在兰州大学举行的第二届生态系统评估与管理(EAM)国际会议青年学者论坛的18场青年学者报告,包括全球变化生态学、植物水分生态学、植物营养与土壤生态学、草畜耦合生态学和生态系统设计与管理等5个分支,报告内容从个体尺度到全球尺度、从自然层面到社会层面均有涉及。将会议主题放入Reynolds等人提出的旱地系统发展范式(DDP)、Jianguo Liu等人提出的人与自然耦合系统理论(CHANS)和Thorvald Srensen提出的生态区概念(ecotope)及脆弱生态系统差别分层管理理论(SFDM)的视角中开展系统地讨论。总结过去20a在干旱农业生态学方面的研究工作,并融合国际前沿进展,提出在年降水量为300-550 mm的地区如何实施"大面积搞生态、小面积搞生产"和以"提高农业生产力和增加植被覆盖率"为核心的生态系统管理模式。该模式映射了未来几十年高效应对全球变化给干旱农业生态系统管理带来的挑战。 相似文献
316.
Gui-Hua Jin Yan-Li Zhou Hong Yang Yan-Ting Hu Yong Shi Ling Li Abu N. Siddique Chang-Ning Liu An-Dan Zhu Cheng-Jun Zhang De-Zhu Li 《植物分类学报:英文版》2021,59(2):341-351
Orphan genes are genetic innovations that lack homologs in other lineages. Orphan genes can rapidly originate and become substantially functional, yet the mechanisms underlying their origins are still largely unknown in plants. Here, we investigated the origin of orphan genes in the Oryza sativa ssp. japonica “Nipponbare” genome using genome‐wide comparisons with 10 closely related Oryza species. We identified a total of 37 orphan genes in the Nipponbare genome that show short sequence lengths, elevated GC content, and absence of introns. Interestingly, half of the identified orphan genes originated by way of a distinctive mechanism that involved the generation of new coding sequences through independent and rapid divergence within the inserted transposable element. Our results provide valuable insight into genetic innovations in the model rice genome that formed on a very short timescale. 相似文献
317.
318.
Siddique Saiful Alom Tamilselvan Thangavel Vishnupriya Manikkannan Balamurugan Elumalai 《Sleep and biological rhythms》2018,16(4):375-385
Sleep and Biological Rhythms - The pressure to stay up longer in our modern society due to constant exposure to artificial light and interactive activities; furthermore, social and economic... 相似文献
319.
Qin Xiaoliang Li Yüze Shi Chengxiao Song Duanpu Wen Xiaoxia Liao Yuncheng Siddique Kadambot H. M. 《Plant and Soil》2019,439(1-2):131-143
Plant and Soil - This study evaluated the influence of cultivar number in wheat cultivar mixtures on aboveground biomass and grain yield across two years with different rainfall. Field experiments... 相似文献
320.
Santha Kumari Merugu V. B. R. Krishnan K Dr. Ravi Kumar K Dr. Siddique Akber Ansari Dr. Irfan Aamer Ansari Prof. Dr. Hari Babu Bollikolla 《化学与生物多样性》2023,20(8):e202201158
An efficient 1,4-dihydropyridine synthesis under mild conditions has been developed. Numerous substrates were tested, with yields of 1,4-dihydropridines ranging from good to excellent and a wide range of functional group tolerance. A549, HT-29, and HepG2 cancer cells were used to investigate the anticancer efficacy of each of the produced compounds. Additionally, in-silico docking studies were conducted to understand the structure-based features of the anticancer mechanism with the cancer medication target of Adenosine A2A receptor as well as the molecular level interactions of the compounds. 相似文献