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排序方式: 共有283条查询结果,搜索用时 15 毫秒
1.
Between 1971 and 1975, Fascioloides magna was found in 46 of 67 (69%) feral swine (Sus scrofa) in southern Texas. Flukes were recovered from swine in areas where F. magna commonly has been recovered from white-tailed deer and cattle. One to 12 flukes were recovered from each infected animal. Their presence was indicated by black hematin pigment on the liver and various other internal organs. Eggs were not detected in the gallbladder or feces of infected animals although mature flukes and eggs were recovered in the livers suggesting that, like cattle, feral swine can be infected but are aberrant hosts for the parasite and do not disseminate eggs. 相似文献
2.
Rahman Daiyan Emma Catherine Lovell Bosi Huang Muhammad Zubair Joshua Leverett Qingran Zhang Sean Lim Jonathan Horlyck Jianbo Tang Xunyu Lu Kourosh Kalantar‐Zadeh Judy N. Hart Nicholas M. Bedford Rose Amal 《Liver Transplantation》2020,10(28)
In this study, scalable, flame spray synthesis is utilized to develop defective ZnO nanomaterials for the concurrent generation of H2 and CO during electrochemical CO2 reduction reactions (CO2RR). The designed ZnO achieves an H2/CO ratio of ≈1 with a large current density (j) of 40 mA cm?2 during long‐term continuous reaction at a cell voltage of 2.6 V. Through in situ atomic pair distribution function analysis, the remarkable stability of these ZnO structures is explored, addressing the knowledge gap in understanding the dynamics of oxide catalysts during CO2RR. Through optimization of synthesis conditions, ZnO facets are modulated which are shown to affect reaction selectivity, in agreement with theoretical calculations. These findings and insights on synthetic manipulation of active sites in defective metal‐oxides can be used as guidelines to develop active catalysts for syngas production for renewable power‐to‐X to generate a range of fuels and chemicals. 相似文献
3.
Saraswathi Umavathi Shahid Mahboob Marimuthu Govindarajan Khalid A. Al-Ghanim Zubair Ahmed P. Virik Norah Al-Mulhm Murugesh Subash Kasi Gopinath C. Kavitha 《Saudi Journal of Biological Sciences》2021,28(3):1808-1815
The present work aims to synthesize zinc oxide (ZnO) nanoparticles via green approaches using leaf extract of Parthenium hysterophorus. UV–vis and FT-IR tests confirmed the existence of biomolecules, active materials, and metal oxides. The X-ray diffraction structural study exposes the ZnO nanoparticles formation with hexagonal phase structures. SEM and TEM analysis reveal surface morphologies of ZnO nanoparticles and most of them are spherical with a size range of 10 nm. ZnO nanoparticles were revealed strong antimicrobial activity against both bacterial and fungal strains. The germination of seeds and vegetative growth of Sesamum indicum has been greatly improved. 相似文献
4.
M. F. Ullah Aamir Ahmad Husain Y. Khan H. Zubair Fazlul H. Sarkar S. M. Hadi 《Cell biochemistry and biophysics》2013,67(2):431-438
Plant-derived dietary antioxidants have attracted considerable interest in recent past for their ability to induce apoptosis and regression of tumors in animal models. While it is believed that the antioxidant properties of these agents may contribute to lowering the risk of cancer induction by impeding oxidative injury to DNA, it could not account for apoptosis induction and chemotherapeutic observations. In this article, we show that dietary antioxidants can alternatively switch to a prooxidant action in the presence of transition metals such as copper. Such a prooxidant action leads to strand breaks in cellular DNA and growth inhibition in cancer cells. Further, the cellular DNA breakage and anticancer effects were found to be significantly enhanced in the presence of copper ions. Moreover, inhibition of antioxidant-induced DNA strand breaks and oxidative stress by Cu(I)-specific chelators bathocuproine and neocuproine demonstrated the role of endogenous copper in the induction of the prooxidant mechanism. Since it is well established that tissue, cellular, and serum copper levels are considerably elevated in various malignancies, such a prooxidant cytotoxic mechanism better explains the anticancer activity of dietary antioxidants against cancer cells. 相似文献
5.
Characterization of antifungal metabolites produced by Lactobacillus plantarum and Lactobacillus coryniformis isolated from rice rinsed water 总被引:1,自引:0,他引:1
Bukhari Shazia Anwer Salman Mahwish Numan Muhammad Javed Muhammad Rizwan Zubair Muhammad Mustafa Ghulam 《Molecular biology reports》2020,47(3):1871-1881
Molecular Biology Reports - A recent spike in demand for chemical preservative free food has derived the scientific community to develop natural ways of food preservation. Therefore,... 相似文献
6.
Saima Muzammil Mohsin Khurshid Iqra Nawaz Muhammad Hussnain Siddique Muhammad Zubair Muhammad Atif Nisar 《Biofouling》2020,36(4):492-504
AbstractAcinetobacter baumannii is a biofilm forming multidrug resistant (MDR) pathogen responsible for respiratory tract infections. In this study, aluminium oxide nanoparticles (Al2O3 NPs) were synthesized and characterized by TEM and EDX and shown to be spherical shaped nanoparticles with a diameter < 10?nm. The minimum inhibitory concentration (MIC) and the minimum bactericidal concentration (MBC) for the Al2O3 NPs ranged between 125 and 1,000?µg ml?1. Exposure to NPs caused cellular membrane disruption, indicated by an increase in cellular leakage of the contents. Biofilm inhibition was 11.64 to 70.2%, whereas attachment of bacteria to polystyrene surfaces was reduced to 48.8 to 51.9% in the presence of NPs. Nanoparticles also reduced extracellular polymeric substance production and the biomass of established biofilms. The data revealed the non-toxic nature of Al2O3 NPs up to a concentrations of 120?µg ml?1 in HeLa cell lines. These results demonstrate an effective and safer use of Al2O3 NPs against the MDR A. baumannii by targeting biofilm formation, adhesion and EPS production. 相似文献
7.
Md. Sahab Uddin Abdullah Al Mamun Zubair Khalid Labu Oscar Hidalgo-Lanussa George E. Barreto Ghulam Md Ashraf 《Journal of cellular physiology》2019,234(6):8094-8112
Autophagy is a preserved cytoplasmic self-degradation process and endorses recycling of intracellular constituents into bioenergetics for the controlling of cellular homeostasis. Functional autophagy process is essential in eliminating cytoplasmic waste components and helps in the recycling of some of its constituents. Studies have revealed that neurodegenerative disorders may be caused by mutations in autophagy-related genes and alterations of autophagic flux. Alzheimer’s disease (AD) is an irrevocable deleterious neurodegenerative disorder characterized by the formation of senile plaques and neurofibrillary tangles (NFTs) in the hippocampus and cortex. In the central nervous system of healthy people, there is no accretion of amyloid β (Aβ) peptides due to the balance between generation and degradation of Aβ. However, for AD patients, the generation of Aβ peptides is higher than lysis that causes accretion of Aβ. Likewise, the maturation of autophagolysosomes and inhibition of their retrograde transport creates favorable conditions for Aβ accumulation. Furthermore, increasing mammalian target of rapamycin (mTOR) signaling raises tau levels as well as phosphorylation. Alteration of mTOR activity occurs in the early stage of AD. In addition, copious evidence links autophagic/lysosomal dysfunction in AD. Compromised mitophagy is also accountable for dysfunctional mitochondria that raises Alzheimer’s pathology. Therefore, autophagic dysfunction might lead to the deposit of atypical proteins in the AD brain and manipulation of autophagy could be considered as an emerging therapeutic target. This review highlights the critical linkage of autophagy in the pathogenesis of AD, and avows a new insight to search for therapeutic target for blocking Alzheimer’s pathogenesis. 相似文献
8.
Badrealam Farheen Khan Hamidullah Sonam Dwivedi Rituraj Konwar Swaleha Zubair Mohammad Owais 《Journal of cellular physiology》2019,234(5):6951-6964
In the recent past, various groups have proposed diverse biocompatible methods for the synthesis of metal nanoparticles (NPs). Besides culture biomass, culture supernatants (CS) are increasingly being explored for the synthesis of NPs; however, with the ever-increasing exploration of various CS in the biofabrication of NPs, it is equally important to explore the potential of various culture media (CMs) in the synthesis of metal NPs. Considering these aspects, in the present investigation, we explore the possible applicability of various CMs in the biofabrication of metal NPs. The synthesis of NPs was primarily followed by UV/VIS spectroscopy, and, thereafter, the NPs were characterized by various physiochemical techniques, including EM, EDX, FT_IR, X-ray diffraction, and DLS measurements, and finally, their anticancer potentialities were investigated against breast cancer. In addition, the NPs were examined in conjunction with artemisinin for therapeutic benefits against aggressive and highly metastatic MDA-MB-231 breast cancer cells. Cumulatively, the results of the present study collated the potentials of various bacterial CMs in the biofabrication of metal NPs and ascertained the efficacy of the as-synthesized silver nanoparticles, especially the combinatorial entity as intriguing breast cancer therapeutics. The data of the present study plausibly assist in advancing the therapeutic applicability of the combinatorial amalgam against aggressive and highly metastatic MDA-MB-231 breast cancer cells. 相似文献
9.
John Hughes Zubair Kabir Kathleen Bennett Joel W. Hotchkiss Frank Kee Alastair H. Leyland Carolyn Davies Piotr Bandosz Maria Guzman-Castillo Martin O’Flaherty Simon Capewell Julia Critchley 《PloS one》2015,10(9)
Objective
Despite rapid declines over the last two decades, coronary heart disease (CHD) mortality rates in the British Isles are still amongst the highest in Europe. This study uses a modelling approach to compare the potential impact of future risk factor scenarios relating to smoking and physical activity levels, dietary salt and saturated fat intakes on future CHD mortality in three countries: Northern Ireland (NI), Republic of Ireland (RoI) and Scotland.Methods
CHD mortality models previously developed and validated in each country were extended to predict potential reductions in CHD mortality from 2010 (baseline year) to 2030. Risk factor trends data from recent surveys at baseline were used to model alternative future risk factor scenarios: Absolute decreases in (i) smoking prevalence and (ii) physical inactivity rates of up to 15% by 2030; relative decreases in (iii) dietary salt intake of up to 30% by 2030 and (iv) dietary saturated fat of up to 6% by 2030. Probabilistic sensitivity analyses were then conducted.Results
Projected populations in 2030 were 1.3, 3.4 and 3.9 million in NI, RoI and Scotland respectively (adults aged 25–84). In 2030: assuming recent declining mortality trends continue: 15% absolute reductions in smoking could decrease CHD deaths by 5.8–7.2%. 15% absolute reductions in physical inactivity levels could decrease CHD deaths by 3.1–3.6%. Relative reductions in salt intake of 30% could decrease CHD deaths by 5.2–5.6% and a 6% reduction in saturated fat intake might decrease CHD deaths by some 7.8–9.0%. These projections remained stable under a wide range of sensitivity analyses.Conclusions
Feasible reductions in four cardiovascular risk factors (already achieved elsewhere) could substantially reduce future coronary deaths. More aggressive polices are therefore needed in the British Isles to control tobacco, promote healthy food and increase physical activity. 相似文献10.
Globally, riparian zones along river banks are widely recognized for their vital role in water regulation and conservation of biodiversity. Here, we specifically investigated the floristic and functional diversity of the vegetation of the riparian zones of protected forests in Kashmir Himalaya, India. A random sampling method was used for site selection while a transect method was used for data collection. Data obtained from the field was subjected to taxonomic and functional classification. Floristic analysis revealed a total of 78 species belonging to 68 genera in 40 families, suggesting an unequal distribution of species among families. Nine families contributed half of the species: Rosaceae was the dominant family with nine (12%) species followed by Asteraceae with eight species (10%), while 23 families were monotypic. In terms of functional trait diversity, herbaceous and perennial taxa dominated, and the biological spectrum showed a dominance of the therophytic life form, indicative of disturbed vegetation. The phenological spectrum revealed that the maximum flowering periods starts in March and extends into May, in which a total of 61% of the species were observed to flower. The leading leaf size spectra were mesophyll with 35%, followed by microphyll (31%). Most (64%) of the species had a simple leaf lamina type. The results of the present study serve as a means to evaluate best management practices, assess restoration and mitigation projects, prioritize riparian related resource management decisions, and establish aquatic life use standards. 相似文献