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61.
Sultana Juhara Mannan Mohammad Abul Kalam Azad Md. Ashik Ullah Abdullah Al Maruf Md. Israt Rayhan Mohammad Shamsul Ahsan Abul Hasnat 《Biological trace element research》2011,140(3):272-283
Drug abuser patients (n = 104), age ranging from 19 to 42 years, were randomly recruited to investigate the serum levels of trace elements (Cu, Zn,
Fe, and Mg), malondialdehyde (MDA), and immunoglobulin (IgG, IgA, and IgM) before and after clinical intervention. Control
group also included 104 healthy individuals. Blood samples were analyzed for determining trace elements, MDA, and immunoglobulin
using atomic absorption spectroscopy, Ultraviolet-Visible (UV-VIS) spectroscopy, and turbidimetry method, respectively. For
serum level of Zn and Fe, the differences between the groups (before intervention, after intervention, and control) were not
significant (p > 0.05). However, significant differences were found in serum copper levels between control group, drug abuser patients,
and before and after intervention (p < 0.05). The concentration of Mg was found to be significantly higher (p = 0.007) in drug abuser patients than the controls, and after intervention, the level was restored to control value. A displacement
of elemental homeostasis was observed in drug abuser patients compared to control, and it was improved after intervention.
An increase in serum concentration of MDA was found in drug abuser patients compared to control subjects (p > 0.05) but was not statistically significant. After intervention, the concentration was restored to control value (p > 0.05). The serum concentrations of IgA and IgM were found to be significantly higher (p < 0.05) in drug abuser patients before intervention than the controls, and the level tended to be restored to control level
after clinical intervention. Serum IgG level was found to be lower in drug abuser patients compared to controls and further
declined significantly (p < 0.05) after intervention. These findings may suggest a possible imbalance in the levels of micronutrients, antioxidants,
and immunoglobulin in drug abuser patients, which tend to be restored to control values after detoxification. 相似文献
62.
Prediction of Anti‐Alzheimer's Activity of Flavonoids Targeting Acetylcholinesterase in silico 下载免费PDF全文
63.
Sunniya Iftikhar Sardraz Khan Aishah Bilal Safia Manzoor Muhammad Abdullah Abdel-Hamid Emwas Salim Sioud Xin Gao Ghayoor Abbas Chotana Amir Faisal Rahman Shah Zaib Saleem 《Bioorganic & medicinal chemistry letters》2017,27(17):4101-4106
Tumor suppressor protein p53 induces cell cycle arrest and apoptotic cell death in response to various cellular stresses thereby preventing cancer development. Activation and stabilization of p53 through small organic molecules is, therefore, an attractive approach for the treatment of cancers retaining wild-type p53. In this context, a series of nineteen chalcones with various substitution patterns of functional groups including chloro, fluoro, methoxy, nitro, benzyloxy, 4-methyl benzyloxy was prepared using Claisen-Schmidt condensation. The compounds were characterized using NMR, HRMS, IR and melting points. Evaluation of synthesized compounds against human colorectal (HCT116) and breast (CAL-51) cancer cell lines revealed potent antiproliferative activities. Nine compounds displayed GI50 values in the low micromolar to submicromolar range; for example (E)-1-phenyl-3-(3,4,5-trimethoxyphenyl)prop-2-en-1-one (SSE14108) showed GI50 of 0.473 ± 0.043 µM against HCT116 cells. Further analysis of these compounds revealed that (E)-3-(4-chlorophenyl)-1-phenylprop-2-en-1-one (SSE14105) and (E)-3-(4-methoxyphenyl)-1-phenylprop-2-en-1-one (SSE14106) caused rapid (4 and 8-h post-treatment) accumulation of p53 in HCT116 cells similar to its induction by positive control, Nutlin-3. Such activities were absent in 3-(4-methoxyphenyl)propiophenone (SSE14106H2) demonstrating the importance of conjugated ketone for antiproliferative and p53 stabilizing activity of the chalcones. We further evaluated p53 levels in the presence of cycloheximide (CHX) and the results showed that the p53 stabilization was regulated at post-translational level through blockage of its degradation. These chalcones can, therefore, act as fragment leads for further structure optimization to obtain more potent p53 stabilizing agents with enhanced anti-proliferative activities. 相似文献
64.
Necla Pehlivan Abdullah Muhammed Yesilyurt Nuran Durmus Sengul Alpay Karaoglu 《Acta Physiologiae Plantarum》2017,39(3):79
Certain number of commercial products has been developed to grow stress resistant plants for the sustainability of agriculture in current era with full of energy dependency and hunger besides global warming. Given the risk of these products on the microbial environment in the rhizosphere and food security of mankind due to the accumulated chemical pollution through the food web, organic fungal plant growth promoting agents might be used. Hence, effects of Trichoderma lixii ID11D (TXD), our local fungal isolate on Zea mays L. cv. Samada 07 as a seed biopriming agent was investigated under dose dependent NaCl stress in this study. Fungus was characterized based on ITS (internal transcribed spacer) regions via clustering approach after isolated from tea plantation area. The higher the NaCl concentration, the more effective the TXD was observed. Improved electron transport rate (ETR), maximum quantum efficiency of PS II (Fv/Fm), the effective quantum yield of PS2 (ΦPS2), photochemical quenching (qP) and decreased non-photochemical quenching (NPQ) was detected in TXD primed plants after NaCl expose. TXD seed biopriming increased the lengths, fresh and dry weights of root/shoots and decreased the lipid peroxidation (MDA) remarkably. Non-enzymatic pathway was found to be more effective than enzymatic one for seed bioprimed plants proven by higher RWC, soluble protein, proline, chlorophyll, carotenoid, and less H2O2 and MDA levels under each dose of NaCl. Detected phenotypic and biochemical improvements pave the way of the potential usage of the formulated fungus biopreperations as a pre-harvest agent in agriculturally important cereals in the future and going beyond lab-based level. 相似文献
65.
In the current study, fifteen halophilic and halotolerant bacteria were isolated from salt-affected soil of ?anl?urfa, Turkey. The isolates were characterized by conventional and molecular techniques (16S rDNA sequence analyses) as belonging to seven different genus including Bacillus (5 isolates), Halobacillus (1 isolate), Oceanobacillus (2 isolates), Halomonas (3 isolate), Nesterenkonia (1 isolate), Chromohalobacter (2 isolates) and Jeotgalibacillus (2 isolates). According to the results obtained, the investigated bacterial strains have high salt tolerance and significant enzyme activities which can improve soil nutrient cycling and fertility. Furthermore, these bacterial strains have been investigated for their ability to dissolve common salts available in salt-affected soils. Salt dissolving experiments showed that two Chromohalobacter isolates were able to dissolve CaCO3 and one of the Halomonas isolate was able to dissolve both CaCO3 and MgCO3. As these bacterial isolates can dissolve CaCO3 and MgCO3, the availability of Ca2+ and Mg2+ ions may increase which can enhance the removal of the excess Na+ in soil profile. 相似文献
66.
67.
Enhanced Electrocatalysis for Energy‐Efficient Hydrogen Production over CoP Catalyst with Nonelectroactive Zn as a Promoter 下载免费PDF全文
Tingting Liu Danni Liu Fengli Qu Dengxing Wang Ling Zhang Ruixiang Ge Shuai Hao Yongjun Ma Gu Du Abdullah M. Asiri Liang Chen Xuping Sun 《Liver Transplantation》2017,7(15)
As a non‐toxic species, Zn fulfills a multitude of biological roles, but its promoting effect on electrocatalysis has been rarely explored. Herein, the theoretic predications and experimental investigations that nonelectroactive Zn behaves as an effective promoter for CoP‐catalyzed hydrogen evolution reaction (HER) in both acidic and alkaline media is reported. Density function theory calculations reveal that Zn doing leads to more thermal‐neutral hydrogen adsorption free energy and thus enhanced HER activity for CoP catalyst. Electrochemical tests show that a Zn0.08Co0.92P nanowall array on titanium mesh (Zn0.08Co0.92P/TM) needs overpotentials of only 39 and 67 mV to drive a geometrical catalytic current of 10 mA cm‐2 in 0.5 m H2SO4 and 1.0 m KOH, respectively. This Zn0.08Co0.92P/TM is also superior in activity over CoP/TM for urea oxidation reaction (UOR), driving 115 mA cm‐2 at 0.6 V in 1.0 m KOH with 0.5 m urea. The high HER and UOR activity of this bifunctional electrode enables a Zn0.08Co0.92P/TM‐based two‐electrode electrolyzer for energy‐saving hydrogen production, offering 10 mA cm‐2 at a low voltage of 1.38 V with strong long‐term electrochemical stability. 相似文献
68.
En route to economical eco‐friendly solvent system in enhancing sustainable recovery of poly(3‐hydroxybutyrate‐co‐4‐hydroxybutyrate) copolymer 下载免费PDF全文
Nik Murniati Nik Man Irdahayu Kannusamy Shantini Kai‐Hee Huong Sevakumaran Vigneswari Nursolehah Abdul Aziz Mohd. Noor Mohd. Azizan Al‐Ashraf Abdullah Amirul 《Engineering in Life Science》2017,17(9):1050-1059
Separation of poly(3‐hydroxybutyrate‐co‐4‐hydroxybutyrate) [P(3HB‐co‐4HB)] from bacterial cell matter is a critical step in the downstream process with respect to material quality and eco‐balance as P(3HB‐co‐4HB) is widely used for biomedical applications. Therefore, an efficient and eco‐based extraction of P(3HB‐co‐4HB) using a combination of NaOH and Lysol in digesting the non‐polymeric cell material (NPCM) digestion is developed. The NaOH and Lysol show synergistic influence on the copolymer extraction at a high purity and recovery of 97 and 98 wt% respectively. The optimized cell digestion method was found applicable to a vast batch of cells containing copolymers from various 4HB monomer compositions. At the largest extraction volume of 100 L, P(3HB‐co‐4HB) with a purity of 89 wt% was extracted with a maximum recovery of 90 wt%. The method developed has also eliminated the cell pretreatment step. The extraction method developed in this research has not only produced an economic and efficient copolymer recovery but has also retained the copolymer quality, in term of its molecular weight and thermal properties. It demonstrates a practical and promising downstream processing method in recovering the copolymer effectively from the bacterial biomass. 相似文献
69.
S. Sakinah Sivan Padma Priya Sharmilah Kumari Fatin Amira Poorani K. Hiba Alsaeedy Mok Pooi Ling Hui-Yee Chee Akon Higuchi Abdullah A. Alarfaj Murugan A. Munusamy Kadarkarai Murugan Che Norma Mat Taib Palanisamy Arulselvan Mariappan Rajan Vasantha Kumari Neela Rukman Awang Hamat Giovanni Benelli S. Suresh Kumar 《Tissue & cell》2017,49(1):86-94
In this research, we characterized the histopathological impact of dengue virus (serotype DENV-2) infection in livers of BALB/c mice. The mice were infected with different doses of DENV-2 via intraperitoneal injection and liver tissues were processed for histological analyses and variation was documented. In the BALB/c mouse model, typical liver tissues showed regular hepatocyte architecture, with normal endothelial cells surrounding sinusoid capillary. Based on histopathological observations, the liver sections of BALB/c mice infected by DENV-2 exhibited a loss of cell integrity, with a widening of the sinusoidal spaces. There were marked increases in the infiltration of mononuclear cells. The areas of hemorrhage and micro- and macrovesicular steatosis were noted. Necrosis and apoptosis were abundantly present. The hallmark of viral infection, i.e., cytopathic effects, included intracellular edema and vacuole formation, cumulatively led to sinusoidal and lobular collapse in the liver. The histopathological studies on autopsy specimens of fatal human DENV cases are important to shed light on tissue damage for preventive and treatment modalities, in order to manage future DENV infections. In this framework, the method present here on BALB/c mouse model may be used to study not only the effects of infections by other DENV serotypes, but also to investigate the effects of novel drugs, such as recently developed nano-formulations, and the relative recovery ability with intact immune functions of host. 相似文献
70.