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41.
Abdul Wadood Muhammad Riaz Amir ul Mulk Momin Khan Sobia Ahsan Haleem Sulaiman Shams Sahib Gul Ayaz Ahmed Muhammad Qasim Farman Ali Zaheer Ul-Haq 《Bioinformation》2014,10(5):299-307
Urease is an important enzyme both in agriculture and medicine research. Strategies based on urease inhibition is critically
considered as the first line treatment of infections caused by urease producing bacteria. Since, urease possess agro-chemical and
medicinal importance, thus, it is necessary to search for the novel compounds capable of inhibiting this enzyme. Several
computational methods were employed to design novel and potent urease inhibitors in this work. First docking simulations of
known compounds consists of a set of arylidine barbiturates (termed as reference) were performed on the Bacillus pasteurii (BP)
urease. Subsequently, two fold strategies were used to design new compounds against urease. Stage 1 comprised of the energy
minimization of enzyme-ligand complexes of reference compounds and the accurate prediction of the molecular mechanics
generalized born (MMGB) interaction energies. In the second stage, new urease inhibitors were then designed by the substitution
of different groups consecutively in the aryl ring of the thiobarbiturates and N, N-diethyl thiobarbiturates of the reference ligands..
The enzyme-ligand complexes with lowest interaction energies or energies close to the calculated interaction energies of the
reference molecules, were selected for the consequent chemical manipulation. This was followed by the substitution of different
groups on the 2 and 5 positions of the aryl ring. As a result, several new and potent diethyl thiobarbiturates were predicted as
urease inhibitors. This approach reflects a logical progression for early stage drug discovery that can be exploited to successfully
identify potential drug candidates. 相似文献
42.
The roles of gibberellic acid (GA3) and ethylenediaminetetraacetic acid (EDTA) in phytoremediation of cadmium (Cd)-contaminated soil by Parthenium hysterophorus plant was investigated. GA3 (10?9, 10?7, and 10?5M) was applied as a foliar spray. EDTA was added to soil in a single dose (160 mg/kg soil) and split doses (40 mg/kg soil, four split doses). GA3 and EDTA were used separately and in various combinations. P. hysterophorus was selected due to its fast growth and unpalatable nature to herbivores to reduce the entrance of metal into the food chain. The Cd phytoextraction potential of the P. hysterophorus plant was evaluated for the first time. Cd significantly reduced plant growth and dry biomass (DBM). GA3 alone increased the plant growth and biomass in Cd-contaminated soil, whereas EDTA reduced it. GA3 in combination with EDTA significantly increased the growth and biomass. The highest significant DBM was found in treatment T3 (10?5M GA3). All treatments of GA3 or EDTA significantly enhanced the plant Cd uptake and accumulation compared with control (C1). The highest significant root and stem Cd concentrations were found in the combination treatment T11 (GA3 10?5M + EDTA split doses), whereas in leaves it was found in the EDTA treatments. Cd concentration in plant parts increased in the order of stem < leaves < roots. The combination treatment T9 (GA3 10?7M + EDTA split doses) showed the significantly highest total Cd accumulation (8 times greater than control C1, i.e., only Cd used). The GA3 treatments accumulated more than 50% of the total Cd in the roots, whereas the EDTA treatments showed more than 50% in the leaves. Root dry biomass showed a positive and significant correlation with Cd accumulation. GA3 is environment friendly as compared with EDTA. Therefore, further investigation of GA3 is recommended for phytoremediation research for the remediation of metal-contaminated soil. 相似文献
43.
Kamran Ashraf Altaf Ahmad Anis Chaudhary Mohd. Mujeeb Sayeed Ahmad Mohd. Amir N. Mallick 《Saudi Journal of Biological Sciences》2014,21(2):159-165
The present investigation was undertaken for the assessment of 12 accessions of Zingiber officinale Rosc. collected from subcontinent of India by RAPD markers. DNA was isolated using CTAB method. Thirteen out of twenty primers screened were informative and produced 275 amplification products, among which 261 products (94.90%) were found to be polymorphic. The percentage polymorphism of all 12 accessions ranged from 88.23% to 100%. Most of the RAPD markers studied showed different levels of genetic polymorphism. The data of 275 RAPD bands were used to generate Jaccard’s similarity coefficients and to construct a dendrogram by means of UPGMA. Results showed that ginger undergoes genetic variation due to a wide range of ecological conditions. This investigation was an understanding of genetic variation within the accessions. It will also provide an important input into determining resourceful management strategies and help to breeders for ginger improvement program. 相似文献
44.
J Bullenkamp N Raulf B Ayaz H Walczak D Kulms E Odell S Thavaraj M Tavassoli 《Cell death & disease》2014,5(10):e1489
Human papillomavirus (HPV) is causative for a new and increasing form of head and neck squamous cell carcinomas (HNSCCs). Although localised HPV-positive cancers have a favourable response to radio-chemotherapy (RT/CT), the impact of HPV in advanced or metastatic HNSCC remains to be defined and targeted therapeutics need to be tested for cancers resistant to RT/CT. To this end, we investigated the sensitivity of HPV-positive and -negative HNSCC cell lines to TRAIL (tumour necrosis factor-related apoptosis-inducing ligand), which induces tumour cell-specific apoptosis in various cancer types. A clear correlation was observed between HPV positivity and resistance to TRAIL compared with HPV-negative head and neck cancer cell lines. All TRAIL-resistant HPV-positive cell lines tested were sensitised to TRAIL-induced cell death by treatment with bortezomib, a clinically approved proteasome inhibitor. Bortezomib-mediated sensitisation to TRAIL was associated with enhanced activation of caspase-8, -9 and -3, elevated membrane expression levels of TRAIL-R2, cytochrome c release and G2/M arrest. Knockdown of caspase-8 significantly blocked cell death induced by the combination therapy, whereas the BH3-only protein Bid was not required for induction of apoptosis. XIAP depletion increased the sensitivity of both HPV-positive and -negative cells to TRAIL alone or in combination with bortezomib. In contrast, restoration of p53 following E6 knockdown in HPV-positive cells had no effect on their sensitivity to either single or combination therapy, suggesting a p53-independent pathway for the observed response. In summary, bortezomib-mediated proteasome inhibition sensitises previously resistant HPV-positive HNSCC cells to TRAIL-induced cell death through a mechanism involving both the extrinsic and intrinsic pathways of apoptosis. The cooperative effect of these two targeted anticancer agents therefore represents a promising treatment strategy for RT/CT-resistant HPV-associated head and neck cancers.Head and neck squamous cell carcinoma (HNSCC) represents the sixth most common cancer worldwide.1 While the overall incidence of HNSCC, traditionally associated with tobacco or alcohol consumption, is declining, a subset of oropharyngeal cancers caused by infection with high-risk types of human papillomavirus (HPV) has risen significantly.2,3 Transformation upon HPV infection occurs mainly because of inactivation of the p53 and retinoblastoma tumour suppressor proteins mediated by the viral oncoproteins E6 and E7, respectively.4HPV-positive (HPV+) cancers represent a distinct subset of HNSCC in terms of biology and clinical behaviour. In general, they are characterised by better overall survival and an improved response to conventional radio-chemotherapy (RT/CT) compared with HPV-negative (HPV−) cancers.5,6 To further minimise treatment-related toxicity without compromising outcome, there have been suggestions of treatment de-escalation in conjunction with targeted therapies.7The novel anticancer agent TRAIL (tumour necrosis factor-related apoptosis-inducing ligand) selectively kills several types of malignant cell lines with little effect on normal cells.8 Recombinant TRAIL or monoclonal antibodies targeting TRAIL receptors (TRAIL-Rs) are currently being tested in phase I/II clinical trials for patients with advanced tumours.9,10 TRAIL induces cell death by binding to TRAIL-R1 or TRAIL-R2, resulting in receptor oligomerisation and formation of the death-inducing signalling complex (DISC)11 and activation of initiator caspase-8.12 Caspase-8 directly activates effector caspase-3 to induce apoptosis through the type I pathway or cleaves the BH3-only protein Bid, generating tBid. This type II pathway involves an amplification loop through the intrinsic pathway of apoptosis characterised by cytochrome c release from the mitochondria, activation of initiator caspase-9 and ultimately caspase-3.13Despite its tumour-selective activity, various cancer cell lines remain resistant to TRAIL, limiting the clinical potential of TRAIL-based monotherapies. Many recent studies focus on combination strategies with other agents to sensitise resistant cells to TRAIL.14 The proteasome inhibitor bortezomib is an FDA-approved drug for the treatment of multiple myeloma, but has shown only little single-agent activity in solid malignancies such as HNSCC while being effective in combination with other treatment options.15, 16, 17 Combining bortezomib with TRAIL-R agonists produced a synergistic cytotoxic effect in various types of cancers. Potential mechanisms underlying sensitisation to TRAIL-induced apoptosis include inhibition of NF-κB signalling, stabilisation of BH3-only proteins, p53 or p21, upregulation of TRAIL-Rs and enhanced stability of caspase-8.18, 19, 20, 21, 22, 23, 24, 25, 26So far, little data is available on the therapeutic potential of TRAIL alone or in combination with bortezomib in HNSCC or other HPV+ related cancers. Treatment with the proteasome inhibitor MG132 sensitised TRAIL-resistant HPV+ cervical cancer cells to TRAIL through p53-dependent upregulation of TRAIL-Rs and inactivation of XIAP.27 Overexpression of E6 was shown to protect colon cancer cells from death receptor-induced apoptosis by affecting the stability of the DISC, indicating a functional link between the presence of E6 and TRAIL signalling.28In this study, we tested the response of HPV+ and HPV− HNSCC cells to treatment with TRAIL alone or combined with bortezomib, revealing a clear pattern of sensitivity to TRAIL depending on HPV status and a synergistic effect when combined with bortezomib. In addition, we identified some of the proteins and pathways involved in the response to TRAIL/bortezomib in HNSCCs. 相似文献
45.
46.
Zeyu Zhang Huihui Wang Yongsheng Wang Feihu Xi Huiyuan Wang Markus V. Kohnen Pengfei Gao Wentao Wei Kai Chen Xuqing Liu Yubang Gao Ximei Han Kaiqiang Hu Hangxiao Zhang Qiang Zhu Yushan Zheng Bo Liu Ayaz Ahmad Yau-Heiu Hsu Steven E. Jacobsen Lianfeng Gu 《The Plant journal : for cell and molecular biology》2021,106(2):435-453
47.
Murat Peksu Uğur Uzer Taner Yildiz Adnan Ayaz F. Saadet Karakulak 《Zeitschrift fur angewandte Ichthyologie》2020,36(6):893-900
In this study, the efficiency of two fishing methods (a) traditional handline commonly used in the Strait of Istanbul and (b) light rock fishing (LRF), which is beginning to spread in recent years, were investigated by monthly sampling between September 2014 and September 2015. One classic handline fishing tackle and one LRF fishing tackle were used in the test fishing exercise. In addition, the effects of the hook sizes (numbers 6, 8 and 10) used in the handline fishery on the size selectivity for horse mackerels were also studied. Catches using both types of fishing gear were mainly composed of Trachurus mediterraneus (89.60%), Scorpeana porcus (5.12%), Sardina pilchardus (1.98%), Atherina boyeri (0.99%), Liza aurata (0.66%), Scorpaena scrofa (0.50%), Pomatomus saltatrix (0.33%), Sprattus sprattus (0.33%) and a few other species. The frequency distributions of horse mackerel caught using handlines and LRF were slightly different and ranged between 6.1–19.0 cm and 9.0–16.0 cm, respectively. Of all the handlines, LRF yielded the highest catch per unit effort (CPUE), 1.295 kg/10 hooks/hour. The log normal model selectivity curve gave the best fit for the T. mediterraneus by using the SELECT method. The modal lengths of horse mackerel caught by handline hook sizes no.10 and no. 8 hook were calculated as 13.4 cm and 17.7 cm, respectively. In addition, the spread values were determined with 3.58 and 4.74, respectively. 相似文献
48.
Ayaz Ghani Molly Weinberg Nusrat Pathan Ramapriya Vidhun Steven Sieber 《Mycopathologia》2018,183(6):973-977
Paracoccidioides infection is a rare entity in the USA. This dimorphic fungus is found in Central and South America and is thought to be acquired by inhalation through the soil. We report a case of Paracoccidioides brasiliensis infection presenting as a clavicular bone lesion, peripancreatic mass, and various skin lesions. A 35-year-old man with a history significant for Hodgkin lymphoma presented with a left clavicular mass that was suspected clinically and radiologically as recurrent Hodgkin lymphoma. He was not experiencing any associated symptoms and was undergoing chemotherapy treatment for his known Hodgkin disease. On CT imaging, the mass was seen as a lytic bone lesion with an overlying soft tissue mass. This was biopsied and histologically diagnosed as a Paracoccidioides brasiliensis infection with associated necrotizing granulomatous inflammation. Also found on the CT scan was an enlarging peripancreatic mass which on endoscopic biopsy had similar histologic findings. In conclusion, this report presents a rare case of Paracoccidioides brasiliensis infection mimicking recurrent Hodgkin lymphoma. 相似文献
49.
Ovais Muhammad Khalil Ali Talha Islam Nazar Ul Ahmad Irshad Ayaz Muhamamd Saravanan Muthupandian Shinwari Zabta Khan Mukherjee Sudip 《Applied microbiology and biotechnology》2018,102(16):6799-6814
Applied Microbiology and Biotechnology - Metal-based nanoparticles have gained tremendous popularity because of their interesting physical, biological, optical, and magnetic properties. These... 相似文献
50.
Ovais Muhammad Khalil Ali Talha Raza Abida Islam Nazar Ul Ayaz Muhammad Saravanan Muthupandian Ali Muhammad Ahmad Irshad Shahid Muhammad Shinwari Zabta Khan 《Applied microbiology and biotechnology》2018,102(10):4393-4408
Applied Microbiology and Biotechnology - Phytochemicals offer immense promise for sustainable development and production of nanotechnology-enabled products. In the present study, Olax nana Wall. ex... 相似文献