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991.
Steert K El-Sayed I Van der Veken P Krishtal A Van Alsenoy C Westrop GD Mottram JC Coombs GH Augustyns K Haemers A 《Bioorganic & medicinal chemistry letters》2007,17(23):6563-6566
The synthesis of novel dipeptidyl alpha-fluorovinyl sulfones using a Horner-Wadsworth-Emmons approach on N-Boc-l-phenylalaninal is described. Inhibitory assays against a Leishmania mexicana cysteine protease (CPB2.8DeltaCTE) revealed low biological activity. Relative rates of Michael additions of 2'-(phenethyl)thiol with vinyl sulfone and alpha-fluorovinyl sulfone were determined, and ab initio calculations on several Michael acceptor model structures were performed; both were in agreement with the biological testing results. 相似文献
992.
Marine indole alkaloid meridianin D analogues have been synthesized starting from the appropriate 3-cyanoacetyl indole. A facile two-step conversion of 3-cyanoacetyl indole to the corresponding cyano meridianin D analogue by treatment with dimethylformamide-dimethylacetal and further cyclization of the resulting enaminonitrile with aminoguanidine is described. Then, alkaline hydrolysis of cyano meridianin D afforded the carboxylic acid analogue. The treatment of acid with 75% H(2)SO(4) afforded the desired 6-debromomeridianin D. Simply treatment of cyano meridianin D analogue with hydrazine hydrate afforded the amidrazone analogue. The biological evaluation indicated that cyano analogue showed good cytotoxic activity with IC(50) values of 0.85 and 2.65microg (against MCF7 and HeLa, respectively), but acid and amidrazone analogues showed high cytotoxicity with IC(50) values of 0.75 and 0.25microg, respectively (against MCF7). 相似文献
993.
Macrophage inflammatory protein-1α: A link between innate immunity and familial mediterranean fever?
Dizdar O Kalyoncu U Karadag O Akdogan A Kiraz S Ertenli I Barista I Calguneri M 《Cytokine》2007,37(1):92-95
The aim of this study is to investigate the relationship between chemokines and the inflammation in Familial Mediterranean Fever (FMF). Forty-nine patients with FMF (41 in remission and 8 in acute attack period) and 20 healthy controls were included in the study. Serum levels of macrophage inflammatory protein-1alpha (MIP-1alpha) were assessed in the patients and the controls, along with other parameters of disease activity, i.e., fibrinogen, C-reactive protein and erythrocyte sedimentation rate. Serum MIP-1alpha levels of the patients with FMF in acute attack period were significantly higher than the patients in remission and healthy controls (p=0.02 and p=0.038, respectively). MIP-1alpha levels were weakly correlated with CRP (r=0.32, p=0.032) levels. MIP-1alpha may have a role in the pathogenesis of FMF attacks. MIP-1alpha and other chemokines may constitute a link between the innate immune system and FMF. 相似文献
994.
The oxidative stress theory of aging offers the best mechanistic elucidation of the aging phenomenon and other age-related
diseases. The susceptibility of an individual depends on the antioxidant status of the body. In humans, the antioxidant system
includes a number of antioxidant enzymes such as superoxide dismutase (SOD) and catalase (CAT), nonenzymatic antioxidants
such as glutathione (GSH), protein –SH, ascorbic acid, and uric acid, and dietary antioxidants. Antioxidant enzymes form the
first line of defense against reactive oxygen species. In an earlier report, we showed that the plasma antioxidant potential
in humans decreases as a function of age and that there are compensatory mechanisms operating in the body which are induced
to maintain the antioxidant capacity during aging. In the present study, we report the relationship between human aging and
antioxidant enzymes SOD and CAT; we also correlate the activity of these enzymes with the antioxidant capacity of the plasma.
Our results show a significantly higher plasma SOD and CAT activity in older individuals than in younger individuals. The
induction in activity of SOD and CAT during human aging may be a compensatory response of the individual to an increased oxidative
stress. 相似文献
995.
Hassanen Eman I. Hussien Ahmed M. Hassan Neven H. Ibrahim Marwa A. Mehanna Sally 《Neurochemical research》2022,47(10):3051-3062
Neurochemical Research - Pesticides are widely used in agriculture to kill pests, but their action is non-selective and results in several hazardous effects on humans and animals. Pesticide... 相似文献
996.
Polat Derya Genc Durmaz Yasar Konar Nevzat Pirouzian Haniyeh Rasouli Toker Omer Said Palabiyik Ibrahim Tasan Murat 《Journal of applied phycology》2022,34(1):375-383
Journal of Applied Phycology - In this study, dried or encapsulated Nannochloropsis oculata microalgal biomass was used in spread samples (0.00–0.75 g (100 g)?1... 相似文献
997.
Elham A. Al-Taifi Al-Aghbari Sama A. Z. El-Ossaily Yasser A. Yeap Guan-Yeow Marae Islam S. Ibrahim Omaima F. Bakhite Etify A. 《Russian Journal of Bioorganic Chemistry》2022,48(2):423-429
Russian Journal of Bioorganic Chemistry - This work describes facile routes towards the synthesis of some novel thiophene derivatives. Thus, condensation of thiophene-2-carboxaldehyde with... 相似文献
998.
999.
Marwa Matboli Ayman E Shafei Mahmoud A Ali Ahmed M Ashry Kamal M Kamal Mohammed Ali Agag Ibrahim Reda Eman Fathy Tash Marwa Ali 《Journal of cellular biochemistry》2019,120(5):7711-7724
Circular RNAs (circRNAs) are a newly validated type of noncoding RNAs recently found to be deregulated in several human cancers. More accurate and specific noninvasive biomarkers are strongly needed for better diagnosis and prognosis of hepatocellular carcinoma (HCC). We performed a bioinformatics analysis to retrieve a novel panel of circRNAs potentially relevant to HCC. We examined their expression in the sera of 68 patients with HCC, 60 patients with chronic hepatitis C, and 36 healthy controls using quantitative polymerase chain reaction. We examined the performance characteristics of the selected circRNA biomarker panel in comparison with alpha-fetoprotein (AFP). In addition, we performed a survival analysis to correlate between their expression levels and patient survival. The circRNAs hsa_circ _00224 and hsa_circ _00520 showed a strong biomarker potential with relatively high sensitivities and specificities compared with AFP. The combined panel including the three circRNAs showed superior performance characteristics relative to those of AFP. The median follow-up period was 26 months. hsa_circ_00520 expression has been shown to be associated with relapse-free survival (P < 0.005). circRNAs hsa_circ_00156, hsa_circ_000224, and hsa_circ_000520 are novel potential biomarkers of high sensitivity and specificity, which could potentially be used in the diagnosis of HCC. 相似文献
1000.
Efficacy of Essential Oils on Fungi Isolated from Archaeological Objects in Saqqara Excavation,Egypt
Neveen S. Geweely Hala A. Afifi Dalia M. Ibrahim Mona M. Soliman 《Geomicrobiology journal》2019,36(2):148-168
The archeological objects constitute an important part of the worldwide cultural heritage. The impact of the fungal activity on the deterioration of cultural heritage is a global problem and their preservation over time is a challenging task. Antifungal activities of 12 essential oils (EOs) (black cumin, castor, cinnamon, clove, cumin, garlic, geranium, lavender, lemongrass, menthe, olive, and thyme) were examined against 16 fungal species isolated from three tested archaeological objects (wall painting stone, wooden statue, and pottery coffin) from Saqqara stores in Egypt. Molecular identification was carried out for the highly frequent species (Aspergillus niger, A. flavus and Rhizopus oryzae) in the three tested archaeological samples. Antifungal activity and minimal inhibitory concentration (MIC) of the tested EOs with different concentrations (0.125, 0.25, 0.5, 0.75, 1?μl/ml) were measured.
The most efficient EOs were thyme (MIC ranged from 0.25–0.75μl/ml) followed by clove (MIC ranged from 0.25–1?μl/ml) and geranium, (MIC ranged from 0.5–1?μl/ml). Thymol (37.1%) and p-Cymene (26.32%) were the active constituents of thyme, while Triacetin (69.36%) and eugenol (28.67) were the most efficient components of clove oil followed by geranium active components (à-Citronellol 20.62% and Geraniol 14.43%). Aspergillus niger was the most resistance species, while Fusarium oxysporum and Penicilium citrinium were the most susceptible ones. 相似文献