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1.
Single-step synthesis of novel 4-hydrazinothiazole derivatives 6a–e was achieved under mild conditions using the sequential four-components method involving isothiocyanate, aminoguanidine, carbonyl adduct, and α-haloketone derivatives. Deprotection of these hydrazinothiazoles was influenced by acylation, providing a novel group of diacylated molecular structures with a broader scope for the design of thiazolyl-containing drugs 7a and 7b . FTIR, 1H/13C NMR, LC–MS spectroscopy, and CHN elemental analyses were used to study the compound chemical structures. Using a 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay on human periodontal ligament fibroblast (HPDLF) cells, the 4-hydrazinothiazole derivatives were screened for cytotoxicity in an in vitro cytotoxicity investigation. The 4-hydrazinothiazole compound 6b bearing an isopropylidene-hydrazino group demonstrated strongly potent cytotoxicity against CAKI1 (IC50 = 1.65 ± 0.24 μM) and A498 (IC50 of 0.85 ± 0.24 μM). Furthermore, the chloroacetyl-containing thiazole compound 7a displayed efficient inhibition of growth against the test cell lines CAKI1 and A498 at low micromolar concentrations, IC50 0.78 and 0.74 μM, respectively. 相似文献
2.
Youssef Dalia El-Bakatoushi Ranya Elframawy Asmaa El-Sadek Laila Badan Ghada El 《Journal of plant research》2023,136(3):305-322
Journal of Plant Research - The current study examined the phylogenetic pattern of medicinal species of the family Apiaceae based on flavonoid groups production, as well as the overall mechanism of... 相似文献
3.
This report describes the cases of three mentally and physically well-developed siblings, 12, 10, and 8 years of age, with varying degrees of isolated valvular pulmonic stenosis not related to age. The severest lesion occurred in the middle patient and was associated with a right-to-left shunt through a patent foramen ovale. The three children had no other siblings, and there was no history of congenital heart disease among close relatives. These cases support the conclusion that genetic factors play a significant role in the development of certain congenital cardiac disorders. 相似文献
4.
5.
Ghada Farouk El-Said 《人类与生态风险评估》2013,19(5):1285-1305
This study examined the bioaccumulation of key metals and other contaminants (SO4, F, Na, K, Ca, Mg, P, Si, Fe, Mn, Zn, Ni, Co, Cu, and Cd) by seaweeds from the Egyptian Mediterranean Sea coast and their risk to human health. Bioaccumulation factor calculations indicated that S, F, Na, K, Zn, Cu, and Cd had high seaweed uptake and this referred to the potential pollution of the coastal area. Multivariate analysis of the studied contaminants confirmed the bioaccumulation factor results as well as the physiological processes in seaweeds. Human health risk assessment of F, Mn, Zn, Ni, Cu, and Cd was conducted using hazard quotient (HQ) and incremental lifetime cancer risk (ILCR) analyses. The carcinogenic assessment of sediments and ingestion of seaweeds using ILCR calculations revealed that Mn, Ni, and Cd in sediments and F and Zn in seaweeds require remedial action in order to reduce their human health risks. Additionally, HQ calculations for the contaminants in seaweeds and reference to toxicological references values from different agencies revealed that F and Co present high human health risk effects. Consequently, the potential public health risks from dietary exposure to hazardous contaminants in seaweeds must be continually subjected to research, regulation, and debate. 相似文献
6.
Ghada S Hassan Daniel Yacoub Nada Alaaeddine Amal Nadiri Yahye Merhi Walid Mourad 《Arthritis research & therapy》2013,15(1):206
Atherosclerosis, now regarded as a chronic inflammatory disease of the arterial wall, and its clinical manifestations have increasingly been associated with rheumatoid arthritis (RA), supporting the notion that autoimmune diseases and vascular disorders share common etiological features. Indeed, evidence pertaining to this matter indicates that inflammation and its multiple components are the driving force behind the pathogenesis of these disorders. Interestingly, CD154 and its receptors have emerged as major players in the development of RA and atherosclerosis, which raises the possibility that this axis may represent an important biological link between both complications. Indeed, CD154 signaling elicits critical inflammatory responses that are common to the pathogenesis of both diseases. Here, we provide an overview of the traditional and disease-related interrelations between RA and vascular abnormalities, while focusing on CD154 as a potential mediator in the development of atherosclerotic events in RA patients. 相似文献
7.
This research highlights the chemical composition, antioxidant and antibacterial activities of essential oils and various crude extracts (using methanol and methylene chloride) from Syzygium cumini leaves. Essential oils were analyzed by gas chromatography-mass spectrometry (GC-MS).The abundant constituents of the oils were: α-pinene (32.32%), β-pinene (12.44%), trans-caryophyllene (11.19%), 1, 3, 6-octatriene (8.41%), delta-3-carene (5.55%), α-caryophyllene (4.36%), and α-limonene (3.42%).The antioxidant activities of all extracts were examined using two complementary methods, namely diphenylpicrylhydrazyl (DPPH) and ferric reducing power (FRAP). In both methods, the methanol extract exhibited a higher activity than methylene chloride and essential oil extracts. A higher content of both total phenolics and flavonoids were found in the methanolic extract compared with other extracts. Furthermore, the methanol extract had higher antibacterial activity compared to methylene chloride and the essential oil extracts. Due to their antioxidant and antibacterial properties, the leaf extracts from S. cumini may be used as natural preservative ingredients in food and/or pharmaceutical industries. 相似文献
8.
Andres Abin-Fuentes Magdy El-Said Mohamed Daniel I. C. Wang Kristala L. J. Prather 《Applied and environmental microbiology》2013,79(24):7807-7817
Microbial desulfurization, or biodesulfurization (BDS), of fuels is a promising technology because it can desulfurize compounds that are recalcitrant to the current standard technology in the oil industry. One of the obstacles to the commercialization of BDS is the reduction in biocatalyst activity concomitant with the accumulation of the end product, 2-hydroxybiphenyl (HBP), during the process. BDS experiments were performed by incubating Rhodococcus erythropolis IGTS8 resting-cell suspensions with hexadecane at 0.50 (vol/vol) containing 10 mM dibenzothiophene. The resin Dowex Optipore SD-2 was added to the BDS experiments at resin concentrations of 0, 10, or 50 g resin/liter total volume. The HBP concentration within the cytoplasm was estimated to decrease from 1,100 to 260 μM with increasing resin concentration. Despite this finding, productivity did not increase with the resin concentration. This led us to focus on the susceptibility of the desulfurization enzymes toward HBP. Dose-response experiments were performed to identify major inhibitory interactions in the most common BDS pathway, the 4S pathway. HBP was responsible for three of the four major inhibitory interactions identified. The concentrations of HBP that led to a 50% reduction in the enzymes'' activities (IC50s) for DszA, DszB, and DszC were measured to be 60 ± 5 μM, 110 ± 10 μM, and 50 ± 5 μM, respectively. The fact that the IC50s for HBP are all significantly lower than the cytoplasmic HBP concentration suggests that the inhibition of the desulfurization enzymes by HBP is responsible for the observed reduction in biocatalyst activity concomitant with HBP generation. 相似文献
9.
Olga G. Cordeiro Mélanie Chypre Nathalie Brouard Simon Rauber Farouk Alloush Monica Romera-Hernandez Cécile Bénézech Zhi Li Anita Eckly Mark C. Coles Antal Rot Hideo Yagita Catherine Léon Burkhard Ludewig Tom Cupedo Fran?ois Lanza Christopher G. Mueller 《PloS one》2016,11(3)
Microenvironment and activation signals likely imprint heterogeneity in the lymphatic endothelial cell (LEC) population. Particularly LECs of secondary lymphoid organs are exposed to different cell types and immune stimuli. However, our understanding of the nature of LEC activation signals and their cell source within the secondary lymphoid organ in the steady state remains incomplete. Here we show that integrin alpha 2b (ITGA2b), known to be carried by platelets, megakaryocytes and hematopoietic progenitors, is expressed by a lymph node subset of LECs, residing in medullary, cortical and subcapsular sinuses. In the subcapsular sinus, the floor but not the ceiling layer expresses the integrin, being excluded from ACKR4+ LECs but overlapping with MAdCAM-1 expression. ITGA2b expression increases in response to immunization, raising the possibility that heterogeneous ITGA2b levels reflect variation in exposure to activation signals. We show that alterations of the level of receptor activator of NF-κB ligand (RANKL), by overexpression, neutralization or deletion from stromal marginal reticular cells, affected the proportion of ITGA2b+ LECs. Lymph node LECs but not peripheral LECs express RANK. In addition, we found that lymphotoxin-β receptor signaling likewise regulated the proportion of ITGA2b+ LECs. These findings demonstrate that stromal reticular cells activate LECs via RANKL and support the action of hematopoietic cell-derived lymphotoxin. 相似文献
10.
Noor Ahmad Shaik Huda M. Al-Kreathy Ghada M. Ajabnoor Prashant Kumar Verma Babajan Banaganapalli 《Saudi Journal of Biological Sciences》2019,26(3):439-448
The somatic mutations in ATP binding cleft of the tyrosine kinase binding domain of EGFR are known to occur in 15–40% of non-small cell lung cancer (NSCLC) patients. Although first and second generation anti-EGFR inhibitors are widely used to treat these patients, their therapeutic efficacy is modest and often results in adverse effects or drug resistance. Therefore, there is a need to develop novel as well as safe anti-EGFR drugs. The rapid emergence of computational drug designing provided a great opportunity to both discover and predict the efficacy of novel EGFR inhibitors from plant sources. In the present study, we designed several chemical analogues of edible curcumin (CUCM) compound and assessed their drug likeliness, ADME and toxicity properties using a diverse range of advanced computational methods. We also have examined the structural plasticity and binding characteristics of EGFR wild-type and mutant forms (S769L and K846R) against ligand molecules like Gefitinib, native CUCM, and different CUCM analogues. Through multidimensional experimental approaches, we conclude that CUCM-36 ((1E,4Z,6E)-1-(3,4-Diphenoxyphenyl)-5-hydroxy-7-(4-hydroxy-3-phenoxyphenyl)-1,4,6-heptatrien-3-one) is the best anti-EGFR compound with high drug-likeness, ADME properties, and low toxicity properties. CUCM-36 compound has demonstrated better affinity towards both wild-type (ΔG is ?8.5?kcal/Mol) and mutant forms (V769L & K846R; ΔG for both is >?9.20?kcal/Mol) compared to natural CUCM and Gefitinib inhibitor. This study advises the future laboratory assays to develop CUCM-36 as a novel drug compound for treating EGFR positive non-small cell lung cancer patients. 相似文献