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151.
J Shafqat O U Beg S J Yin Z H Zaidi H J?rnvall 《European journal of biochemistry》1990,194(2):337-341
A trypsin inhibitor from the venom of the cobra Naja naja naja has been isolated by a single step of reverse-phase high-performance liquid chromatography. The protein strongly inhibits trypsin (Ki = 3.5 pM). The primary structure was determined by peptide analysis of the [14C]carboxymethylated inhibitor. The 57-residue polypeptide chain belongs to the family of Kunitz-type inhibitors, and exhibits 42% residue identity with bovine pancreatic trypsin inhibitor. The structure shows only 70% identity with the corresponding peptide from the Capa cobra (Naja nevia), establishing that the inhibitor molecule exhibits extensive variations. Functionally, a basic residue at position P3' correlates with strong inhibition. 相似文献
152.
Mahmood Rasool Arif Malik Muhammad Abdul Basit Ashraf Mahwish Arooj Asia Kiran Sulayman Waquar Ujala Ayyaz Ayesha Zahid Ahmad Zaheer Abdul Jabbar Maryam Zain Amir Raza Asim Mehmood Tahira Batool Qaisrani Zeenat Mirza Mohammed Hussein Al-Qahtani Sajjad Karim Absarul Haque 《Saudi Journal of Biological Sciences》2018,25(8):1724-1728
Background
Cancer patients when treated with different chemotherapeutic drugs often develop mild to severe sight threatening diseases during or after chemotherapy. The mechanism involved in the pathogenesis of ocular toxicities is poorly understood. Oxidative stress, inflammation and MMPs (angiogenic factor) are involved in the progression of chemotherapy related ocular disorders.Materials and methods
The concentration of oxidative stress markers such as MDA, NO and levels of different antioxidant molecules such as SOD, CAT, GSH, GPx, GPr, VIT A, VIT E and VIT C present in the serum of chemotherapy treated patients (n?=?50) and in normal persons (n?=?20) were estimated by the direct spectrophotometric method while the concentration of TNF-α and MMP-9 activity were determined using human TNF-α and MMP-9 ELISA kits.Results
The concentration of SOD and CAT (0.356?±?0.05?μg/dl and 1.26?±?0.01?μmol/mol of protein) was significantly lower as compared to that (1.09?±?0.03?μg/dl and 3.99?±?0.04?μmol/mol of protein) in controls. The levels of GPx (0.06?±?0.01?mmol/dl) in the cancer patients were much lower than those in the controls (0.78?±?0.06?mmol/dl). Lower level of GSH (0.96?±?0.003?μg/dl) in serum of the diseased group was observed as compared to healthy group (7.26?±?1.40?μg/dl). The level of Vit A, Vit C and Vit E was lower in systemic circulation of cancer patients (109.99?±?6.35?μg/ml, 1.26?±?0.36?μg/ml and 1.29?±?0.191?μg/ml) as compared to control subjects (166.35?±?14.26?μg/ml, 3.25?±?0.099?μg/ml and 6.354?±?2.26?μg/ml) respectively. The concentration of nitric oxide was significantly higher in the cancer patients (45.26?±?6.35?ng/ml) than that in the normal subjects (16.35?±?3.26?ng/ml). The higher concentration of MDA (8.65?±?3.26?nmol/ml) was observed in the patients than normal ones (1.254?±?0.065?nmol/ml). The quantity of TNF-α was significantly higher in chemotherapy treated patients (32.68?±?4.33?pg/ml) as compared to the control group (20.979?±?1.98?pg/ml). Significantly higher concentration of MMP-9 (40.26?±?3.26?ng/ml) was observed in the cancer patients than the controls (7.256?±?1.95?ng/ml).Conclusion
Lower levels of antioxidant enzymes and non-enzymatic small molecules and higher levels of oxidative stress and inflammatory clinical parameters such as NO, MDA, TNF-α and MMP-9 may be involved in the pathogenesis of systemic chemotherapy related ocular complications such as cataract, glaucoma, blepharitis, retinitis pigmentosa, macular degeneration, pterygium and retinal degeneration. 相似文献153.
Vilhelmsson M Zargari A Crameri R Rasool O Achour A Scheynius A Hallberg BM 《Journal of molecular biology》2007,369(4):1079-1086
Atopic eczema (AE) is a chronic inflammatory disease in which genetic predisposition and environmental factors such as microorganisms contribute to the symptoms. The yeast Malassezia Sympodialis, part of the normal human cutaneous flora, can act as an allergen eliciting specific IgE and T-cell reactivity in patients with AE. The major M. sympodialis allergen Mala s 1 is localized mainly in the yeast cell wall and exposed on the cell surface. Interestingly, Mala s 1 does not exhibit any significant sequence homology to known proteins. Here we present the crystal structure of Mala s 1 determined by single-wavelength anomalous dispersion techniques using selenomethionine-substituted Mala s 1. Mala s 1 folds into a 6-fold beta-propeller, a novel fold among allergens. The putative active site of Mala s 1 overlaps structurally to putative active sites in potential homologues, Q4P4P8 and Tri 14, from the plant parasites Ustilago maydis and Gibberella zeae, respectively. This resemblance suggests that Mala s 1 and the parasite proteins may have similar functions. In addition, we show that Mala s 1 binds to the phosphoinositides (PI) PI(3)P, PI(4)P, and PI(5)P, lipids possibly playing a role in the localization of Mala s 1 to the cell surface. The crystal structure of Mala s 1 will provide insights into the role of this major allergen in the host-microbe interactions and induction of an allergic response in AE. 相似文献
154.
Yedukondalu Nalli Mohd Saleem Dar Nasima Bano Javeed Ur Rasool Aminur R. Sarkar Junaid Banday Aadil Qadir Bhat Basit Rafia Ram A Vishwakarma Mohd Jamal Dar Asif Ali 《Bioorganic & medicinal chemistry letters》2019,29(9):1043-1046
Neuropathic pain is a debilitating form of treatment-resistant chronic pain caused by damage to the nervous system. Cannabinoids have been known for suppressing neuropathic pain by modulating the endo cannabinoid system. Since the canonical Wnt/β-catenin signaling has recently been implicated in pain sensation, we investigated the impact of major cannabinoids (1–6) from the leaves of Cannabis sativa and an epoxy derivative of compound 2, here upon referred to as 2a, on modulating Wnt/β-catenin signaling pathway. The results presented in this study show that compound 1, 2 and 2a exhibited potent inhibitory activity against Wnt/β-catenin pathway in a dose-dependent manner. Compound 2a was seen to inhibit this pathway at slightly lower concentrations than its parent molecule 2, under similar conditions. Taken together, compound 1, 2 and 2a, by virtue of their inhibition of Wnt/β-catenin signaling pathway, could be developed as effective neuroprotective agents for the management of neuropathic pain. 相似文献
155.
Muhammad Amjad Bashir Shafqat Saeed Asif Sajjad Khalid Ali Khan Hamed Ali Ghramh Muhammad Ahmed Shehzad Hussani Mubarak Nosheen Mirza Shahzadi Mahpara Muhammad Ishaq Asif Rehmani Mohammad Javed Ansari 《Saudi Journal of Biological Sciences》2019,26(7):1835-1842
This study investigated pollinator assemblage diversity and richness in four forested ecosystems of southern Punjab, Pakistan, with different landscape types. Pirowal is situated in the plains of irrigated Punjab, Lal Suhanra is part of a sandy desert ecosystem, Ghazi Ghat is part of the Indus River delta, and Fort Munro is located in dry hilly mountains. A yearlong survey of pollinator populations was carried out in these four forested ecosystems from January to December of 2010. Fortnightly hand netting was performed for collecting flower-visiting insects whereas, pan traps of three colors (white, blue, and yellow) were deployed for collecting the data. A total of 8,812 individuals from two orders (Lepidoptera and Diptera) were observed, including 22 families and 154 species. Bees were the most abundant, with 4,502 individuals, and the most species-rich taxa, with 70 species in five families, followed by flies having 2,509 individuals and 51species in 10 families. Wasps were the least abundant with 1,801 individuals and 33 species in seven families. The assemblage structure of pollinator communities as visualized through rank abundance curves showed that there were many species with low abundance and only a few species with a much higher abundance. The most abundant species among the bees, in order, were Nomia sp.3, Megachile bicolor, and Colletes sp.3; among flies, Syrphus sp.2, Calliphoridae sp.1, and Empididae sp.4; and among wasps, Tiphiidae sp.1, Myzininae sp.2, and Scelionidae sp.1. 相似文献
156.
Mahmood Rasool Arif Malik Tariq Tahir Butt Muhammad Abdul Basit Ashraf Rabia Rasool Ayesha Zahid Sulayman Waquar Muhammad Asif Ahmad Zaheer Abdul Jabbar Maryam Zain Asim Mehmood Tahira Batool Qaisrani Imran Riaz Malik Sami Ullah Khan Zeenat Mirza Absarul Haque Mohammed Hussein Al-Qahtani Sajjad Karim 《Saudi Journal of Biological Sciences》2019,26(2)
Objective
To study the putative effects of Advanced Oxidation Protein Products (AOPPs) and Advanced Glycation End Products (AGEs) in the development and progression of cardiovascular disease (CVD).Methodology
AGEs, AOPPs, e-NOS, lipid profile, circulating stress and inflammatory biomarkers were evaluated among fifty cardiovascular patients and fifty controls. Independent student’s t-test was done for statistical analysis.Results
The malondialdehyde mean level in CVD patients (5.45?nmol/ml) was significantly higher than control (1.36?nmol/ml) (p value?=?0.018). Nitric oxide in CVD patients (55.72?ng/ml) was remarkably increased as compared to normal subjects (19.19?ng/ml). A significant change in the mean serum level of AGEs in CVD patients (2.74?ng/ml) and normal individuals (0.85?ng/ml) was recorded (p value?=?0.000). The AOPPs also showed significant increased levels in CVD group (132.07?ng/ml) in comparison with normal subjects (83.05?ng/ml) (p value?=?0.011). The mean eNOS serum level in CVD group (15.50?U/L) was higher than control group (11.28?U/L) (p value?=?0.004). Cardiovascular disease patients, in comparison with healthy controls, showed increased level of total cholesterol (5.48?mmol/L vs 4.45?mmol/L), triglycerides (2.59?mmol/L vs 1.24?mmol/L), and low density lipoprotein (2.47?mmol/L vs 2.31?mmol/L) along with decrease in high density lipoprotein (1.39?mmol/L vs 1.74?mmol/L). The mean MMP-11 serum levels in CVD group (98.69?ng/ml) was almost double of control group (45.60?ng/ml) (p value?=?0.017). The mean serum level of TNF-α and IL1-α were 32.16?pg/ml and 6.64?pg/ml in CVD patient. The significant decreasing trend of SOD (p value?=?0.041), CAT (p value?=?0.018), GSH (p value?=?0.036) and GRx (p value?=?0.029) but increasing drift of GPx (0.023) level was observed in CVD patients.Conclusion
This study provides strong evidence that CVD patients presented with elevated oxidative stress, enhanced inflammation and lipid profile in their serum. Therefore, the study strongly approves that AGEs, AOPPs, inflammatory and lipoxidative biomarkers hold predictive potential in causing and aggravating the disease, thus by controlling these factors CVD progression can be inhibited. 相似文献157.
Ahmad Zaheer Arif Malik Ahmad Sher Muther Mansoor Qaisrani Asim Mehmood Sami Ullah Khan Muhammad Ashraf Zeenat Mirza Sajjad Karim Mahmood Rasool 《Saudi Journal of Biological Sciences》2019,26(5):1061-1067
ObjectivePhosphate (P) and zinc (Zn) are essential plant nutrients required for nodulation, nitrogen-fixation, plant growth and yield. Mostly applied P and Zn nutrients in the soil are converted into unavailable form. A small number of soil microbes have the ability to transform unsolvable forms of P and Zn to an available form. P-Zn-solubilizing rhizobacteria are potential alternates for P and Zn supplement. In the present study, the effect of two P-Zn-solubilizing bacterial strains (Bacillus sp. strain AZ17 and Pseudomonas sp. strain AZ5) was evaluated on the growth of chickpea plant.MethodologyBoth strains were purified from the rhizospheric soil of chickpea plant grown-up in sandy soil and rain-fed area (Thal desert). In vitro, both strains solubilize P and Zn as well both strain produce IAA and organic acids. In the field experiments, conducted in the rain-fed area, the positive influence of inoculation with both bacterial isolates AZ5 and AZ17 on chickpea growth was observed.ResultsThe application of inoculum (strains AZ5 and AZ17) resulted in up to 17.47% and 17.34% increase in grain yield of both types of chickpea grown in fertilized and non-fertilized soil, respectively over non-inoculated control. Strain AZ5 was the most effective inoculum, increasing up to 17.47%, 16.04%, 26.32%, 22.53%, 26.12% and 22.59% in grain yield, straw weight, nodules number, dry weight of nodules, Zn uptake and P uptake respectively, over control.ConclusionThese results indicated that Pseudomonas sp. strain AZ5 and Bacillus sp. strain AZ17 can serve as effective microbial inocula for chickpea, particularly in the rain-fed area. 相似文献
158.
Shaik Nayab Rasool Shaik Shabeena Culala Rajasekharaudayar Kesavulu Singarapu Babu Asanapuram Mohan Babu Vemula Venkatramu 《Luminescence》2022,37(5):784-790
Novel erbium(III) ion-doped borate-based glasses (Er3+:BCNF) by conventional melt-quenching technique were designed and synthesized. The glasses were characterized for their structural, vibrational and spectroscopic properties. The nephelauxetic ratio, bonding parameters, and Judd–Ofelt (JO) intensity parameters (Ωλ λ = 2, 4 and 6) were determined by using absorption spectrum of 1 mol% Er2O3 doped glass. These JO parameters were utilized to derive radiative properties for various excited states of erbium(III) ions. Emission cross-section for 4I13/2 → 4I15/2 transition of erbium(III) ions was computed through McCumber theory. The decay curves for (2H11/2, 4S3/2) and 4I13/2 levels were recorded and analysed. All the results of Er3+:BCNF glasses revealed that the studied glasses are efficient and thermally stable and could be suitable for display devices, optical amplification and green laser applications. 相似文献
159.
Global alterations in epigenetic landscape are now recognized as a hallmark of cancer. Epigenetic mechanismssuch as DNA methylation,histone modifications,nucleosome positioning and non-coding RNAs are proven to have strong association with cancer. In particular,covalent post-translational modifications of histone proteins are known to play an important role in chromatin remodeling and thereby in regulation of gene expression. Further,histone modifications have also been associated with different aspects of carcinogenesis and have been studied for their role in the better management of cancer patients. In this review,we will explore and discuss how histone modifications are involved in cancer diagnosis,prognosis and treatment. 相似文献
160.
Nonhuman Amyloid Oligomer Epitope Reduces Alzheimer’s-Like Neuropathology in 3xTg-AD Transgenic Mice
Suhail Rasool Hilda Martinez-Coria Saskia Milton Charles G. Glabe 《Molecular neurobiology》2013,48(3):931-940
Accumulation of beta-amyloid (Aβ) is an important pathological event in Alzheimer’s disease (AD). It is now well known that vaccination against fibrillar Aβ prevents amyloid accumulation and preserves cognitive function in transgenic mouse models. To study the effect of vaccination against generic oligomer epitopes, Aβ oligomers, islet amyloid polypeptide oligomers, random peptide oligomer (3A), and Aβ fibrils were used to vaccinate 3xTg-AD, which develop a progressive accumulation of plaques and cognitive impairment. Subcutaneous administration of these antigens markedly reduced total plaque load (Aβ burden) and improved cognitive function in the 3xTg-AD mouse brains as compared to controls. We demonstrated that vaccination with this nonhuman amyloid oligomer generated high titers of specifically antibodies recognizing Aβ oligomers, which in turn inhibited accumulation of Aβ pathology in mice. In addition to amyloid plaques, another hallmark of AD is tau pathology. It was found that there was a significant decline in the level of hyper-phosphorylated tau following vaccination. We have previously shown that immunization with 3A peptide improves cognitive function and clears amyloid plaques in Tg2576 mice, which provides a novel strategy of AD therapy. Here, we have shown that vaccination with 3A peptide in 3xTg-AD mice not only clears amyloid plaques but also extensively clears abnormal tau in brain. 相似文献