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71.
72.
In vitro antibiofilm and anti‐adhesion effects of magnesium oxide nanoparticles against antibiotic resistant bacteria
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Sumreen Hayat Saima Muzammil Muhammad Hidayat Rasool Zonaira Nisar Syed Zajif Hussain Anjum Nasim Sabri Saba Jamil 《Microbiology and immunology》2018,62(4):211-220
73.
Faiza Gulzar Qaisar Mahmood Zulfiqar Ahmad Bhatti Bibi Saima Zeb Shahida Shaheen Tahir Hayat Naeem Shahid Tahseen Zeb 《World journal of microbiology & biotechnology》2018,34(8):119
Wastewater treatment based on ecological principles is a low cost and highly desirable solution for the developing countries like Pakistan. The present study evaluated the effectiveness of biological treatment systems including Internal Circulation (IC) anaerobic bioreactor and constructed wetlands (CWs) containing macrophytes and mixed algal cultures for industrial wastewater treatment. The IC bioreactor reduced COD (52%), turbidity (89%), EC (24%) of the industrial wastewater. However, the effluents of IC bioreactor did not comply with National Environmental Quality Standards (NEQS) of Pakistan. Post-treatment of IC bioreactor effluents was accomplished in CW containing macrophytes (Arundo donax and Eichhornia crassipes) and mixed algal culture. The CWs planted with macrophytes lowered the concentrations of COD (89%) and turbidity (99%). CWs with algal biomass were not effective in further polishing the effluent. Inhibition of algal biomass growth was observed due to physicochemical characteristics of wastewater. The integrated treatment system consisting of IC bioreactor and macrophytes was found more suitable option for industrial wastewater treatment. 相似文献
74.
Shafaqat Ali Muhammad Rizwan Najeeb Ullah Saima Aslam Bharwana Muhammad Waseem Muhammad Ahsan Farooq Ghulam Hasan Abbasi Mujahid Farid 《Acta Physiologiae Plantarum》2016,38(11):262
Accumulation of excess copper (Cu) in agricultural soils can decrease growth and quality of crops grown on these soils and a little information is available on the role of silicon (Si) in reducing Cu toxicity in plants. A hydroponic study was conducted to investigate the effects of Si (1.0 mM) on growth and physiology of cotton seedlings grown on different Cu (0, 25, and 50 µM) concentrations. Elevated levels of Cu decreased growth, biomass, photosynthetic pigments, and gas exchange characteristics, and increased the electrolyte leakage (EL), hydrogen peroxide (H2O2), and thiobarbituric acid reactive substances (TBARS) contents in leaf, stem, and roots of cotton seedlings. Cu stress alone decreased the activities of key antioxidant enzymes in cotton seedlings. Exogenous application of Si alleviated the toxic effects of Cu on cotton seedlings by improving growth, photosynthetic pigments, and gas exchange characteristics under Cu stress. The Si application decreased Cu concentrations in leaves, stem, and roots as compared with the control plants. Furthermore, Si decreased oxidative stress as evidenced by decreased EL, H2O2, and TBARS contents, and increased the antioxidant enzyme activities in cotton seedlings. This study provides evidences of Si-mediated reduction of Cu toxicity in cotton seedlings at physiological and biochemical levels. 相似文献
75.
Bibi Saima Afsar Khan Riffat Un Nisa Tariq Mahmood Khurshid Ayub 《Journal of molecular modeling》2016,22(4):81
The thermally allowed electrocyclic reaction syn-cyclophanediene (CPD) to dihydropyrene (DHP) was compared with the disallowed thermal electrocyclic reaction in anti CPD through density functional theory (DFT) calculations at the B3LYP/6-31?+?G(d) level. Moreover, the results were also compared with the electrocyclization of 1,3,5 hexatriene to 1,3-cyclohexadiene . The Woodward-Hoffmann (W-H) allowed thermal reaction in syn CPD 11 has a calculated activation barrier of 6.23 kcal mol?1, compared with 29 kcal mol?1 for the electrocyclization of 1,3,5 hexatriene to 1,3-cyclohexadiene. The enhanced acceleration of electrocyclization is believed to arise from geometrically enforced spatially aligned termini of the hexatriene. Substituents at the electrocyclic terminus of cyclophanediene significantly affected (up to three fold) the activation barriers. Mono-substitution of CPD has substituent dependent acceleration or deceleration whereas di-substitution always increased the activation barrier. The activation barrier for electrocyclization in 33 is 4.44 kcal mol?1, which is the lowest activation barrier for any thermal electrocyclic reaction. Cyclophanedienes (CPDs) substituted with electron-rich substituents cyclized with high activation barriers and vice versa, a phenomenon significantly different from electrocyclic reaction of 1,3,5-hexatriene where no such trend is traceable. Comparison of W-H allowed and forbidden electrocyclization in syn and anti CPDs, respectively, revealed quite similar electronic demand, although the transition states are different in nature. The transition state for a W-H forbidden reaction is biradicaloid, with most of the spin density at the electrocyclic termini; however, the transition state for a W-H allowed reaction has no such contribution. We also believe that this is the first study of its type, where W-H allowed and forbidden reactions are compared on a similar set of molecules, and compared for electronic effect through substituents. 相似文献
76.
Saima Nusrat Mohammad Khursheed Siddiqi Masihuz Zaman Nida Zaidi Mohammad Rehan Ajmal Parvez Alam Atiyatul Qadeer Ali Saber Abdelhameed Rizwan Hasan Khan 《PloS one》2016,11(7)
Exogenous drugs that are used as antidote against chemotheray, inflammation or viral infection, gets absorbed and interacts reversibly to the major serum transport protein i.e. albumins, upon entering the circulatory system. To have a structural guideline in the rational drug designing and in the synthesis of drugs with greater efficacy, the binding mechanism of an antineoplastic and anti-inflammatory drug Nordihydroguaiaretic acid (NDGA) with human and bovine serum albumins (HSA & BSA) were examined by spectroscopic and computational methods. NDGA binds to site II of HSA with binding constant (Kb) ~105 M-1 and free energy (ΔG) ~ -7.5 kcal.mol-1. It also binds at site II of BSA but with lesser binding affinity (Kb) ~105 M-1 and ΔG ~ -6.5 kcal.mol-1. The negative value of ΔG, ΔH and ΔS for both the albumins at three different temperatures confirmed that the complex formation process between albumins and NDGA is spontaneous and exothermic. Furthermore, hydrogen bonds and hydrophobic interactions are the main forces involved in complex formation of NDGA with both the albumins as evaluated from fluorescence and molecular docking results. Binding of NDGA to both the albumins alter the conformation and causes minor change in the secondary structure of proteins as indicated by the CD spectra. 相似文献
77.
Seasonal changes in epididymal weight and histology were studied in relation to testicular function in the adult spiny-tailed lizard, Uromastix hardwicki, over a period of 1 year. The eipdidymal weights, tubular diameter, and epithelial height increased in March, reaching a peak in April. This peak coincided with sperm maturation, elevated plasma testosterone levels, and release of sperm into the epididymis. The epididymal weights decreased in May following a sudden regression of the testis early in the month. The epididymal weights decreased further during June and remained low until February. The diameter of the duct and the height of the epithelial cells also decreased in May and the epididymal epithelium maintained a low histological profile from June to February. The fall testicular recrudescence was not accompanied by a change either in the weight or the histological structure of the epididymis. Administration of oFSH (0.1 mg) daily for 7 days during the sexually quiescent period induced a significant increase in the weight of the epididymis and epithelial height of the duct. Administration of testosterone alone, (2.0 mg) daily for the same period and under identical conditions, did not induce a change in the weight of epididymis or its histology. A possible permissive role of gonadotrophin in the hormonal regulation of the lizard epididymis has been suggested. 相似文献
78.
A chemical fractionation procedure, previously found applicable to bovine thymus and bovine and ovine palatine tonsils, was used to fractionate rabbit and hog thymus. With respect to the chemical fractionation steps, yields of fractions, and optical and electrophoretic properties, extracts from hog and rabbit thymus were indistinguishable from similar extracts prepared from calf thymus. The study provides composition and yield data applicable to the thymus of a small mammal readily available in most laboratories. 相似文献
79.
Masihuz Zaman Syed Mohammad Zakariya Saima Nusrat Mohsin Vahid Khan Atiyatul Qadeer Mohammad Rehan Ajmal 《Journal of biomolecular structure & dynamics》2017,35(7):1407-1419
Neurodegenerative disorders are mainly associated with amyloid fibril formation of different proteins. Stem bromelain (SB), a cysteine protease, is known to exist as a molten globule state at pH 10.0. It passes through the identical surrounding (pH 10.0) in the gut epithelium of intestine upon oral administration. Protein–surfactant complexes are widely employed as drug carriers, so the nature of surfactant toward protein is of great interest. The present work describes the effect of cationic surfactants (CTAB & DTAB) and their hydrophobic behavior toward amyloidogenesis behavior of SB at pH 10.0. Multiple approaches including light scattering, far UV-CD, turbidity measurements, and dye binding assay (ThT, Congo red and ANS) were performed to measure the aggregation propensity of SB. Further, we monitored the hydrodynamic radii of aggregates formed using dynamic light scattering technique. Structure of fibrils was also visualized through fluorescence microscopy as well as TEM. At pH 10.0, low concentration of CTAB (0–200 μM) induced amyloid formation in SB as evident from a prominent increase in turbidity and light scattering, gain in β-sheet content, and enhanced ThT fluorescence intensity. However, further increase in CTAB concentration suppressed the fibrillation phenomenon. In contrast, DTAB did not induce fibril formation at any concentration used (0–500 μM) due to lower hydrophobicity. Net negative charge developed on protein at high pH (10.0) might have facilitated amyloid formation at low concentration of cationic surfactant (CTAB) due to electrostatic and hydrophobic interactions. 相似文献
80.