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21.
Mehmet Varol Kadriye Benkli Ayşe T. Koparal Rakibe B. Bostancıoğlu 《Drug and chemical toxicology》2019,42(4):436-443
Drug design and discovery studies are important because of the prevalence of diseases without available medical cures. New anticancer agents are particularly urgent because of the high mortality rate associated with cancer. A series of mononuclear gold (III) and platinum (II) complexes based on boronated phenylalanine (BPA) were designed and synthesized using 4,4’-dimethyl-2,2’-dipyridyl (L1) or 1,10-phenanthroline-5,6-dion (L2) ligands to obtain promising anticancer drug candidates. Proton nuclear magnetic resonance, infrared, mass spectrometry, and elemental analyses were utilized for chemical characterizations. Cell viability, cancer cell colony formation, endothelial tube formation, and cytoskeleton staining assays were performed using A549 lung adenocarcinoma and human umbilical vein endothelial cells (HUVECs) to investigate preliminary pharmacological activities. L1-based platinum (II) complex (BPA-L1-Pt) was the most promising complex, and has similar activity with the approved chemotherapy drug cis-platinum. Half maximal inhibitory concentration values for BPA-L1-Pt were 9.15 µM on A549s and 16.61 µM on HUVECs; the values for cis-platinum were 5.24 µM on A549s and 23.14 µM on HUVECs. Consequently, further synthesis studies should be performed to boost the cancer cell selectivity feature of BPA by varying metal and ligand types. 相似文献
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An important part of fundamental research in catalysis is based on theoretical and modeling foundations which are closely connected with studies of single-crystalline catalyst surfaces. These so-called model catalysts are often prepared in the form of epitaxial thin films, and characterized using advanced material characterization techniques. This concept provides the fundamental understanding and the knowledge base needed to tailor the design of new heterogeneous catalysts with improved catalytic properties. The present contribution is devoted to development of a model catalyst system of CeO2 (ceria) on the Cu(111) substrate. We propose ways to experimentally characterize and control important parameters of the model catalyst—the coverage of the ceria layer, the influence of the Cu substrate, and the density of surface defects on ceria, particularly the density of step edges and the density and the ordering of the oxygen vacancies. The large spectrum of controlled parameters makes ceria on Cu(111) an interesting alternative to a more common model system ceria on Ru(0001) that has served numerous catalysis studies, mainly as a support for metal clusters. 相似文献
24.
Rubens Souza de OLIVEIRA Lanna Jamile Corrêa da COSTA Fernanda Atanaena Gon?alves de ANDRADE Wilson UIEDA Luzia Fátima Alves MARTORELLI Ana Paula de Arruda Geraldes KATAOKA Elizabeth Salbé Travassos da ROSA Pedro Fernando da Costa VASCONCELOS Armando de Souza PEREIRA Ant?nio Ismael Barros do CARMO Marcus Emanuel Barroncas FERNANDES 《Revista do Instituto de Medicina Tropical de S?o Paulo》2015,57(6):497-503
The outbreaks of rabies in humans transmitted by Desmodus rotundus in 2004 and 2005,
in the northeast of the Brazilian State of Para, eastern Amazon basin, made this a
priority area for studies on this zoonosis. Given this, the present study provides
data on this phenomenon in an urban context, in order to assess the possible
circulation of the classic rabies virus (RABV) among bat species in Capanema, a town
in the Amazon basin. Bats were collected, in 2011, with mist nets during the wet and
dry seasons. Samples of brain tissue and blood were collected for virological and
serological survey, respectively. None of the 153 brain tissue samples analyzed
tested positive for RABV infection, but 50.34% (95% CI: 45.67-55.01%) of the serum
samples analyzed were seropositive. Artibeus planirostris was the most common
species, with a high percentage of seropositive individuals (52.46%, 95% CI: 52.31
52.60%). Statistically, equal proportions of seropositive results were obtained in
the rainy and dry seasons (c2 = 0.057, d.f. = 1, p = 0.88). Significantly
higher proportions of males (55.96%, 95% CI: 48.96-62.96%) and adults (52.37%, 95%
CI: 47.35-57.39%) were seropositive. While none of the brain tissue samples tested
positive for infection, the high proportion of seropositive specimens indicates that
RABV may be widespread in this urban area. 相似文献
25.
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27.
H N David M Dhilly M Degoulet G Poisnel C Meckler N Vallée J-é Blatteau J-J Risso M Lemaire D Debruyne J H Abraini 《Translational psychiatry》2015,5(7):e594
We investigated the effects of the noble gas argon on the expression of locomotor sensitization to amphetamine and amphetamine-induced changes in dopamine release and mu-opioid neurotransmission in the nucleus accumbens. We found (1) argon blocked the increase in carrier-mediated dopamine release induced by amphetamine in brain slices, but, in contrast, potentiated the decrease in KCl-evoked dopamine release induced by amphetamine, thereby suggesting that argon inhibited the vesicular monoamine transporter-2; (2) argon blocked the expression of locomotor and mu-opioid neurotransmission sensitization induced by repeated amphetamine administration in a short-term model of sensitization in rats; (3) argon decreased the maximal number of binding sites and increased the dissociation constant of mu-receptors in membrane preparations, thereby indicating that argon is a mu-receptor antagonist; (4) argon blocked the expression of locomotor sensitization and context-dependent locomotor activity induced by repeated administration of amphetamine in a long-term model of sensitization. Taken together, these data indicate that argon could be of potential interest for treating drug addiction and dependence. 相似文献
28.
Lars J Vatten Tom I L Nilsen P?l R Romundstad Wenche B Dr?yvold Jostein Holmen 《European journal of cardiovascular prevention and rehabilitation》2006,13(6):909-915
OBJECTIVE: To investigate whether cardiovascular mortality related to obesity could be modified by physical activity. DESIGN: Mortality follow-up. SETTING: Population study. PARTICIPANTS: Participants in a health survey: 34 868 women and 32 872 men free from known cardiovascular disease or diabetes at baseline. MAIN OUTCOME MEASURES: Total cardiovascular mortality. MAIN RESULTS: During 16 years of follow-up, 3026 women and 3526 men had died from cardiovascular causes. In middle age, obesity [body mass index (BMI) of 30 or higher] was associated with increased risk of cardiovascular death, but the association weakened with age. After 70, there was no association between BMI and cardiovascular death. At all ages, a lower level of physical activity was associated with a higher cardiovascular mortality. In women with high physical activity, indicated by at least 30 min of moderate to vigorous activity more than once a week, cardiovascular mortality was only slightly higher in the obese compared to lean women (adjusted relative risk, 1.27; 95% confidence interval, 0.80-2.00). In men with high physical activity, cardiovascular mortality was, however, significantly higher among the obese (relative risk, 1.62; 95% confidence interval, 1.09-2.40). In both genders cardiovascular mortality was substantially higher in obese people who reported no regular physical activity compared to obese people with a high level of physical activity. CONCLUSION: In obese women, being highly active may, to a large extent, compensate for the risk-increasing effect of being obese, whereas in obese men who engage in a high level of physical activity, the risk of cardiovascular death may be higher than in lean and equally active men. 相似文献
29.
Jaros?aw Felu? Wojciech Rad?o Bart?omiej Kowalczyk 《Chirurgia narzadów ruchu i ortopedia polska》2006,71(2):107-112
Nine wrists in eight patients were treated surgically between 1988 and 2003 for symptomatic Madelung's deformity. The pain of involved wrist followed by forearm deformation fulfilled criteria for surgery. Closing wedge osteotomy of the distal radius were carried out eight times accompanied by shortening of the ulna (four patients), excision of the distal ulna (one patient), and no ulnar surgery (three patients). Pain relieved after surgery. The follow up period ranged from 1 to 9.5 years. No pour results were stated in subjective patient's estimation during final check up. Wrist appearance were stated to be satisfactory. Limitation of the range of motion concerning supination and pronation of the forearm were stated invariably. X-ray retrospective assessment of the inclination angle, lunate coverage and presence of arthritic changes were conducted. Time and method of surgical treatment for Madelung's deformity should be considered individually. 相似文献
30.
Manuel P Magalh?es 《Revista portuguesa de cardiologia》2003,22(10):1197-1199