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排序方式: 共有238条查询结果,搜索用时 15 毫秒
181.
Nur Hanisah Mustafa Mahendran Sekar Shivkanya Fuloria M. Yasmin Begum Siew Hua Gan Nur Najihah Izzati Mat Rani Subban Ravi Kumarappan Chidambaram Vetriselvan Subramaniyan Kathiresan V. Sathasivam Srikanth Jeyabalan Subasini Uthirapathy Sivasankaran Ponnusankar Pei Teng Lum Vijay Bhalla Neeraj Kumar Fuloria 《Molecules (Basel, Switzerland)》2022,27(6)
Sarsasapogenin is a natural steroidal sapogenin molecule obtained mainly from Anemarrhena asphodeloides Bunge. Among the various phytosteroids present, sarsasapogenin has emerged as a promising molecule due to the fact of its diverse pharmacological activities. In this review, the chemistry, biosynthesis and pharmacological potentials of sarsasapogenin are summarised. Between 1996 and the present, the relevant literature regarding sarsasapogenin was obtained from scientific databases including PubMed, ScienceDirect, Scopus, and Google Scholar. Overall, sarsasapogenin is a potent molecule with anti-inflammatory, anticancer, antidiabetic, anti-osteoclastogenic and neuroprotective activities. It is also a potential molecule in the treatment for precocious puberty. This review also discusses the metabolism, pharmacokinetics and possible structural modifications as well as obstacles and opportunities for sarsasapogenin to become a drug molecule in the near future. More comprehensive preclinical studies, clinical trials, drug delivery, formulations of effective doses in pharmacokinetics studies, evaluation of adverse effects and potential synergistic effects with other drugs need to be thoroughly investigated to make sarsasapogenin a potential molecule for future drug development. 相似文献
182.
Geethanjali Thayumanavan Srikanth Jeyabalan Shivkanya Fuloria Mahendran Sekar Monica Ravi Logesh Kumar Selvaraj Logeshwari Bala Kumarappan Chidambaram Siew Hua Gan Nur Najihah Izzati Mat Rani M. Yasmin Begum Vetriselvan Subramaniyan Kathiresan V. Sathasivam Dhanalekshmi U. Meenakshi Neeraj Kumar Fuloria 《Molecules (Basel, Switzerland)》2022,27(8)
Bisphenol A (BPA), a well-known xenoestrogen, is commonly utilised in the production of polycarbonate plastics. Based on the existing evidence, BPA is known to induce neurotoxicity and behavioural issues. Flavonoids such as silibinin and naringenin have been shown to have biological activity against a variety of illnesses. The current research evaluates the neuropharmacological effects of silibinin and naringenin in a zebrafish model against neurotoxicity and oxidative stress caused by Bisphenol A. In this study, a novel tank diving test (NTDT) and light–dark preference test (LDPT) were used in neurobehavioural investigations. The experimental protocol was planned to last 21 days. The neuroprotective effects of silibinin (10 μM) and naringenin (10 μM) in zebrafish (Danio rerio) induced by BPA (17.52 μM) were investigated. In the brine shrimp lethality assay, the 50% fatal concentrations (LC50) were 34.10 μg/mL (silibinin) and 91.33 μg/mL (naringenin) compared to the standard potassium dichromate (13.15 μg/mL). The acute toxicity investigation found no mortality or visible abnormalities in the silibinin- and naringenin-treated groups (LC50 > 100 mg/L). The altered scototaxis behaviour in LDPT caused by BPA was reversed by co-supplementation with silibinin and naringenin, as shown by decreases in the number of transitions to the light zone and the duration spent in the light zone. Our findings point to BPA’s neurotoxic potential in causing altered scototaxis and bottom-dwelling behaviour in zebrafish, as well as the usage of silibinin and naringenin as potential neuroprotectants. 相似文献
183.
Russian Journal of Organic Chemistry - A series of novel amide-functionalized imidazo[1,2-a]pyrimidin-5(1H)-ones were synthesized by propargylation of the key intermediate... 相似文献
184.
Zhibin Luo Sangepu Bhavanarushi Avula Sreenivas Narra Srikanth Reddy Anil Valeru Imran Khan Yin Xu Bin Liu Jimin Xie 《Journal of heterocyclic chemistry》2020,57(9):3334-3341
An efficient chemoselective synthesis of 1,3-thiazine-2-ylidenes was achieved via annulations of β-aroyl-thioacetamide with propargyl alcohols using BF3 OEt2 as Lewis acid catalyst. A broad spectrum of substrates was well tolerated under the mild reaction conditions producing desired thiazine heterocyclics in good yields. 相似文献
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186.
Classical approximation results show that any circuit of size and depth has an ‐error probabilistic polynomial over the reals of degree . We improve this upper bound to , which is much better for small values of . We then use this result to show that ‐wise independence fools circuits of size and depth up to error at most , improving on Tal's strengthening of Braverman's result that ‐wise independence suffices. To our knowledge, this is the first PRG construction for that achieves optimal dependence on the error . We also prove lower bounds on the best polynomial approximations to . We show that any polynomial approximating the function on bits to a small constant error must have degree at least . This result improves exponentially on a result of Meka, Nguyen, and Vu (Theory Comput. 2016). 相似文献
187.
To enable the reliable quantification of ciprofloxacin in human urine, a sensitive and selective assay based on liquid chromatography–tandem mass spectrometry was developed. The chromatographic separation of the ciprofloxacin was carried out on a Zorbex Eclipse C18 column using methanol and ammonium acetate as a mobile phase by the gradient elution method. The developed assay covered a wide range of concentrations (1.56–100 ng/mL) with a lower limit of detection of 0.76 ng/mL. Quantification was performed using the multiple reaction monitoring transitions 331.8/231 for ciprofloxacin and 362/318 for ofloxacin (internal standard). This assay was validated for linearity, accuracy, precision and recovery. The validated method was then applied to the biodegradability of ciprofloxacin (99%) from human urine in the microbial fuel cell. 相似文献
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190.
Jithin Joy Cintil Jose Xiaoyan Yu Lovely Mathew Sabu Thomas Srikanth Pilla 《Cellulose (London, England)》2017,24(10):4313-4323
In this study, the thermal, wetting and viscoelastic properties of biodegradable poly(butylene succinate)–isora nanofibril (PBS–INF) composites were investigated. Optical polarizing microscopy showed that incorporating INF in PBS enhanced the number of nucleation sites while also reducing its spherulitic size. Wide-angle X-ray diffraction results showed the influence of INF on the crystal structure of PBS. Dynamic mechanical analysis results revealed increases in storage and loss moduli with increasing INF content. Differential scanning calorimetry analysis showed that incorporating INF facilitated crystallization at higher temperatures. INF slightly enhanced the melting behavior of PBS matrix. Thermogravimetric analysis results demonstrated no definitive change in the thermal stability of PBS upon inclusion of INF. Contact angle studies showed enhancement in the hydrophilic nature of PBS–INF composites. Overall, INF had a positive influence on the thermophysical properties of PBS providing a feasibility for using PBS–INF composites in automotive interiors, food packaging and related applications. 相似文献