排序方式: 共有70条查询结果,搜索用时 15 毫秒
51.
Iqra Sarfraz Azhar Rasul Farhat Jabeen Tayyaba Sultana evki Adem 《Molecules (Basel, Switzerland)》2022,27(20)
The reliance of tumor cells on aerobic glycolysis is one of the emerging hallmarks of cancer. Pyruvate kinase M2 (PKM2), an important enzyme of glycolytic pathway, is highly expressed in a number of cancer cells. Tumor cells heavily depend on PKM2 to fulfill their divergent energetic and biosynthetic requirements, suggesting it as novel drug target for cancer therapies. Based on this context, we performed enzymatic-assay-based screening of the in-house phenolic compounds library for the identification of PKM2 inhibitors. This screening identified silibinin, curcumin, resveratrol, and ellagic acid as potential inhibitors of PKM2 with IC50 values of 0.91 µM, 1.12 µM, 3.07 µM, and 4.20 µM respectively. For the determination of Ki constants and the inhibition type of hit compounds, Lineweaver–Burk graphs were plotted. Silibinin and ellagic acid performed the competitive inhibition of PKM2 with Ki constants of 0.61 µM and 5.06 µM, while curcumin and resveratrol were identified as non-competitive inhibitors of PKM2 with Ki constants of 1.20 µM and 7.34 µM. The in silico screening of phenolic compounds against three binding sites of PKM2 provided insight into the binding pattern and functionally important amino residues of PKM2. Further, the evaluation of cytotoxicity via MTT assay demonstrated ellagic acid as potent inhibitor of cancer cell growth (IC50 = 20 µM). These results present ellagic acid, silibinin, curcumin, and resveratrol as inhibitors of PKM2 to interrogate metabolic reprogramming in cancer cells. This study has also provided the foundation for further research to validate the potential of identified bioactive entities for PKM2 targeted-cancer therapies. 相似文献
52.
Patrick J. A. Hill Neil R. Banerjee Arshad Ali Iffat Jabeen Gordon R. Osinski Fred J. Longstaffe 《Journal of mass spectrometry : JMS》2019,54(8):667-675
We present a procedure for the determination of the isotopic ratios of silicon and oxygen from the same aliquot of anhydrous silicate material. The sample is placed in a bromine pentafluoride atmosphere as it is heated with a CO2 laser system releasing silicon tetrafluoride and oxygen gasses. The oxygen gas is then purified to remove other reaction by‐products through several liquid nitrogen traps before being captured onto a molecular sieve and transferred to an isotope ratio mass spectrometer. The silicon tetrafluoride gas is then purified using a supplementary line by repeatedly freezing to ?196°C with liquid nitrogen and then thawing with an ethanol slurry at ?110°C through a series of metal and Pyrex traps. The purified gas is then condensed into a Pyrex sample tube before it is transferred to an isotope ratio mass spectrometer for silicon isotope ratio measurements. This system has silicon yields of greater than 90% for pure quartz, olivine, and garnet standards and has a reproducibility of ±0.1‰ (2σ) for pure quartz for both oxygen and silicon isotope measurements. Meteoritic samples were also successfully analyzed to demonstrate this system's ability to measure the isotopic ratio composition of bulk powders with precision. This unique technique allows for the fluorination of planetary material without the need for wet chemistry. Though designed to analyze small aliquots of meteoritic material (1.5 to 3 mg), this approach can also be used to investigate refractory terrestrial samples where traditional fluorination is not suitable. 相似文献
53.
Russian Journal of Organic Chemistry - A series of new triazole ligands has been synthesized via copper-catalyzed cycloaddition reaction of readily available azides and alkynes. The synthesized... 相似文献
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55.
Sana Yaqoob Nourina Nasim Rahila Khanam Yan Wang Almas Jabeen Urooj Qureshi Zaheer Ul-Haq Hesham R. El-Seedi Zi-Hua Jiang Farooq-Ahmad Khan 《Molecules (Basel, Switzerland)》2021,26(5)
In search of anti-inflammatory compounds, novel scaffolds containing isonicotinoyl motif were synthesized via an efficient strategy. The compounds were screened for their in vitro anti-inflammatory activity. Remarkably high activities were observed for isonicotinates 5–6 and 8a–8b. The compound 5 exhibits an exceptional IC50 value (1.42 ± 0.1 µg/mL) with 95.9% inhibition at 25 µg/mL, which is eight folds better than the standard drug ibuprofen (11.2 ± 1.9 µg/mL). To gain an insight into the mode of action of anti-inflammatory compounds, molecular docking studies were also performed. Decisively, further development and fine tuning of these isonicotinates based scaffolds for the treatment of various aberrations is still a wide-open field of research. 相似文献
56.
Sabiha-Javied Mahmood Arif Tufail M. Ikram Shahzad M. Jabeen Mahwish Nasir Rabiya Nawaz R. 《Journal of Radioanalytical and Nuclear Chemistry》2017,314(3):1877-1883
Radon concentration was measured by using 39CR track etched detectors in five fertilizer warehouses in the Punjab province of Pakistan. The average concentration of radon was determined to be 20–88 Bq m−3. Annual effective dose (AED) and excess lifetime cancer risk (ELCR) have also been assessed using the models of UNSCEAR and ICRP. The corresponding annual dose and ELCR to the workers of warehouses have been estimated to be 0.30–1.02 mSv year−1 and 0.44–1.02%, respectively.
相似文献57.
Hidayat Hussain Natalia Root Farah Jabeen Ahmed Al-Harrasi Ahmed Al-Rawahi Manzoor Ahmad Zahid Hassan Ghulam Abbas Fazal Mabood Afzal Shah Amin Badshah Amjad Khan Riaz Ahmad Ivan R. Green Siegfried Draeger Barbara Schul Karsten Krohn 《中国化学快报》2014,25(12):1577-1579
A new metabolite,named seimatoric acid(1),representing a new oxobutanoic acid derivative has been isolated from Seimatosporium sp., in addition to four known compounds viz.,2-hydroxymethyl-4β,5α,6β-trihydroxycyclohex-2-enone(2),(-)-phyllostine(3),(+)-epiepoxydon(4) and(+)-epoxydon monoacetate(5).Similarly one new benzoic acid derivative,named colletonoic acid(6) was isolated from the ethyl acetate fraction of Colletotrichum sp.The structures of the new compounds were elucidated by detailed ~1 H NMR,~(13)C NMR,COSY,HMQC.HMBC spectroscopic analysis,and HR-E1-MS.Seimatoric acid(1)was also isolated from another taxonomical unidentified fungal strain 4295 in ourgroup.The structures of the known compounds were elucidated by their spectral data comparison to literature data.Preliminary studies showed that colletonoic acid(6) showed good antibacterial,antifungal,and antialgal activities. 相似文献
58.
Optimality conditions are derived for a nonlinear fractional program in which a support function appears in the numerator and denominator of the objective function as well as in each constraint function. As an application of these optimality conditions, a dual to this program is formulated and various duality results are established under generalized convexity. Several known results are deduced as special cases. 相似文献
59.
Shakeela Jabeen Goutam Ghosh Lloyd Lapoot Andrés M. Durantini Alexander Greer 《Photochemistry and photobiology》2023,99(2):637-641
The sensitized photooxidation of ortho-prenyl phenol is described with evidence that solvent aproticity favors the formation of a dihydrobenzofuran [2-(prop-1-en-2-yl)-2,3-dihydrobenzofuran], a moiety commonly found in natural products. Benzene solvent increased the total quenching rate constant (kT) of singlet oxygen with prenyl phenol by ~10-fold compared to methanol. A mechanism is proposed with preferential addition of singlet oxygen to prenyl site due to hydrogen bonding with the phenol OH group, which causes a divergence away from the singlet oxygen ‘ene’ reaction toward the dihydrobenzofuran as the major product. The reaction is a mixed photooxidized system since an epoxide arises by a type I sensitized photooxidation. 相似文献
60.
GaAs nanowires (NWs) are grown on GaAs (1 1 1) B substrates in a molecular beam epitaxy system, by Au-assisted vapor–liquid–solid growth. We compare the characteristics of NWs elaborated with As2 or As4 molecules. In a wide range of growth temperatures, As4 leads to growth rates twice faster than As2. The shape of the NWs also depends on the arsenic species: with As4, regular rods can be obtained, while pencil-like shape results from growth with As2. From the analysis of the incoming fluxes, which contributes to the NWs formation, we conclude that the diffusion length of Ga adatoms along the NW sidewalls is smaller under As2 flux as compared to that under As4 flux. It follows that As2 flux is favourable to the formation of radial heterostructures, whereas As4 flux is preferable to maintain pure axial growth. 相似文献