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1.
Primary structure of -chain of pigeon is presented. It was determined by amino acid sequence analysis of intact -chain and its peptides obtained by the enzymatic and chemical cleavage. Comparison of amino acid sequence of the chain with other available data shows 14 Ile, 61 Lys, and 113 Ile as residues specific to pigeon. One important replacement at 11 contact is 55 MetSer. 相似文献
2.
Primary structure of β-chain of pigeon is presented. It was determined by amino acid sequence analysis of intact β-chain and its peptides obtained by the enzymatic and chemical cleavage. Comparison of amino acid sequence of the chain with other available data shows β 14 Ile, β61 Lys, and β113 Ile as residues specific to pigeon. One important replacement at α1β1 contact is β55 Met→Ser. 相似文献
3.
Plasma Physics Reports - Three-dimensional self-gravito-acoustic solitary waves (SGASWs) in a general (but realistic) self-gravitating degenerate quantum plasma media consisting of heavy... 相似文献
4.
Khan Muhammad Tahir Zeb Muhammad Tariq Ahsan Hina Ahmed Abrar Ali Arif Akhtar Khalid Malik Shaukat Iqbal Cui Zhilei Ali Sajid Khan Anwar Sheed Ahmad Manzoor Wei Dong-Qing Irfan Muhammad 《Archives of microbiology》2021,203(1):59-66
Archives of Microbiology - Severe acute respiratory syndrome virus 2 (SARS-CoV-2) belongs to the single-stranded positive-sense RNA family. The virus contains a large genome that encodes four... 相似文献
5.
Hina Gul Muhammad Awais Salina Saddick Yazeed Ahmed Falak Sher Khan Eilaf Ahmed Umara Afzal Syed Muhammad Zaigham Abbas Naqvi Muhammad Asghar Khan Muhammad Gulfraz Ghazala Kaukab Raja 《Saudi Journal of Biological Sciences》2021,28(1):247-254
Liver disorders may occur as a result of exposure to chemical compounds capable of inducing the oxidative stress and hepatic injuries. The aim of present study was to investigate the effects of flower extracts of B. Variegata for the treatment of liver injury induced by the CCl4. About 1 ml/kg body weight (b.w) of CCl4 was induced to experimental mice by intraperitoneal way for 14 days. The methanol and chloroform extracts (100, 200 and 300 mg/kg b.w) were administered to experimental animals for 14 days along with standard drug Silymarine (100 mg/kg b.w). The extracts alone showed no evidence of hepatic toxicity but animals exposed to CCl4 without the treatment with B. Variegata presented variations in levels of liver enzymes, antioxidant enzymes, proteins and blood cells as well as injuries in liver cells were also observed during histopathological study. However, after the treatments especially with 300 mg/kg b.w of methanol flower extracts levels of liver markers (ALT, AST and ALP), antioxidant enzymes and blood cells decreases and turned towards normal levels. Whereas level of total proteins and bilirubin was improved and damaged liver cells were repaired. The curative activity of flower extracts can be correlated to the higher potential of antioxidants and occurrence of Quercetin and some other organic compounds those were investigated from flower extracts of B. Variegata during HPLC and GC-MS analysis. The finding of this study supports the use of B. Variegata flower formulation in folk medicines. 相似文献
6.
7.
This study described a simple and green approach for the synthesis of silver nanoparticles (AgNPs) employing benzoin gum water extract as a reducing and capping agent and their applications. The AgNPs were characterized by ultraviolet–visible spectrophotometer, X-ray diffraction pattern, field emission transmission electron microscopy, dynamic light scattering, zeta potential and fourier transform infrared spectroscopy. The AgNPs showed promising antimicrobial activity against various pathogens (Gram-negative, Gram-positive and fungus) and possessed high free radical scavenging activity (104.5 ± 7.21 % at 1 mg/ml). In addition, the AgNPs exhibited strong cytotoxicity towards human cervical cancer and human lung cancer cells as compared to the normal mouse macrophage cells. Moreover, the AgNPs possessed anti-biofilm activity against Escherichia coli, and compatibility to human keratinocyte HaCaT cells, which suggests the use of dressing with the AgNPs in chronic wound treatment. Therefore, AgNPs synthesized by benzoin gum extract are comparatively green and may have broad spectrum potential application in biomedicine. 相似文献
8.
Hina Siddiqui Muhammad Arslan Bashir Kulsoom Javaid Arsalan Nizamani Huma Bano Sammer Yousuf 《Journal of enzyme inhibition and medicinal chemistry》2016,31(6):1392-1403
Tyramine derivatives 3–27 were synthesized by using conventional and environmental friendly ultrasonic techniques. These derivatives were then evaluated for the first time for their α-glucosidase (Sources: Saccharomyces cerevisiae and mammalian rat-intestinal acetone powder) inhibitory activity by using in vitro mechanism-based biochemical assays. Compounds 7, 14, 20, 21 and 26 were found to be more active (IC50?=?49.7?±?0.4, 318.8?±?3.7, 23.5?±?0.9, 302.0?±?7.3 and 230.7?±?4.0?μM, respectively) than the standard drug, acarbose (IC50?=?840.0?±?1.73?μM (observed) and 780?±?0.028?μM (reported)) against α-glucosidase obtained from Saccharomyces cerevisiae. Kinetic studies were carried out on the most active members of the series in order to determine their mode of inhibition and dissociation constants. Compounds 7, 20 and 26 were found to be the competitive inhibitors of α-glucosidase. These compounds were also screened for their protein antiglycation, and dipeptidyl peptidase-IV (DPP-IV) inhibitory activities. Only compounds 20, 22 and 27 showed weak antiglycation activity with IC50 values 505.27?±?5.95, 581.87?±?5.50 and 440.58?±?2.74?μM, respectively. All the compounds were found to be inactive against DDP-IV enzyme. Inhibition of α-glucosidase, DPP-IV enzymes and glycation of proteins are valid targets for the discovery of antidiabetic drugs. Cytotoxicity of compounds 3–27 was also evaluated by using mouse fibroblast 3T3 cell lines. All the compounds were found to be noncytotoxic. The current study describes the synthesis α-glucosidase inhibitory activity of derivatives, based on a natural product tyramine template. The compounds reported here may serve as the starting point for the design and development of novel α-glucosidase inhibitors as antidiabetic agents. 相似文献
9.
Nadezhda Tikhmyanova Nicholas Paparoidamis James Romero-Masters Xin Feng Farheen Sultana Mohammed Poli Adi Narayana Reddy Shannon C. Kenney Paul M. Lieberman Joseph M. Salvino 《Bioorganic & medicinal chemistry letters》2019,29(16):2259-2264
Epstein-Barr virus (EBV) is a human herpesvirus that infects over 90% of the world's population that persists as a latent infection in various lymphoid and epithelial malignancies. The total number of EBV associated malignancies is estimated to exceed 200,000 new cancers per year. Current chemotherapeutic treatments of EBV-positive cancers include broad-spectrum cytotoxic drugs that ignore the EBV positive status of tumors and have limited safety and selectivity. In an effort to develop new and more efficacious molecules for inducing EBV reactivation, we have developed high-throughput screening assays to identify a class of small molecules (referred to as the C60 series) that efficiently activate the EBV lytic cycle in multiple latency types, including lymphoblastoid and nasopharyngeal carcinoma cell lines. In this paper we report our preliminary structure activity relationship studies and demonstrate reactivation of EBV in the SNU719 gastric carcinoma mouse model and the AGS-Akata gastric carcinoma mouse model. 相似文献
10.
Razia Sultana Rizwan Arif Manish Rana Saiema Ahmedi Rabiya Mehandi Akrema Nikhat Manzoor Rahisuddin 《Luminescence》2022,37(3):408-421
An oxadiazole derivative 2 was prepared by condensation reaction through cyclization of semicarbazone in the presence of bromine; the structural confirmation was supported by 1H and 13C nuclear magnetic resonance (NMR) spectroscopy, Fourier transform-infrared spectroscopy, and liquid chromatography-mass spectrometry. Its sensing ability towards Ni2+ ion was examined showing a binding constant of 1.04 × 105 compared with other suitable metal cations (Ca2+, Co2+, Cr3+, Ag+, Pb2+, Fe3+, Mg2+, and K+) using ultraviolet–visible (UV–vis) and fluorescence spectroscopic studies. The minimum concentration of Ni2+ ions and limit of detection was found to be 9.4 μM. A job's plot gave the binding stoichiometry ratio of oxadiazole derivative 2 vs Ni2+ ions as 2:1. Furthermore, the intercalative binding mode of oxadiazole derivative 2 with calf thymus DNA was supported by ultraviolet–visible (UV–vis) and fluorescent light, viscosity, cyclic voltammetry, time-resolved fluorescence, and circular dichroism measurements. The molecular docking result gave the binding score for oxadiazole derivative 2 as −6.5 kcal/mol, which further confirmed the intercalative interaction. In addition, the antifungal activity of oxadiazole derivative 2 was also screened against several fungal strains (C. albicans, C. glabrata, and C. tropicalis) by broth dilution and disc diffusion methods. In antioxidant studies, the oxadiazole derivative 2 showed potential scavenging activity against 2,2-diphenyl-1-picrylhydrazyl and H2O2 free radicals. 相似文献