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31.
Michael H Parrish Janine M Dutcher Keely A Muscatell Tristen K Inagaki Mona Moieni Michael R Irwin Naomi I Eisenberger 《Social cognitive and affective neuroscience》2022,17(8):723
Self-enhancement, the tendency to view oneself positively, is a pervasive social motive widely investigated in the psychological sciences. Relatively little is known about the neurocognitive mechanisms underlying this motive, specifically in social-evaluative situations. To investigate whether positive emotion regulation circuitry, circuitry involved in modulating positive affect, relates to the self-enhancement motive in social contexts, we conducted an functional magnetic resonance imaging (fMRI) study in a healthy young adult sample. We hypothesized that self-enhancement indices (state and trait self-esteem) would relate to greater functional connectivity between right ventrolateral prefrontal cortex (RVLPFC), a region implicated in emotion regulation, and the ventral striatum (VS), a region associated with reward-related affect, during a social feedback task. Following social evaluation, participants experienced stable or decreased state self-esteem. Results showed that stable state self-esteem from pre- to post-scan and higher trait self-esteem related to greater RVLPFC–VS connectivity during positive evaluation. Stable-state self-esteem also related to greater RVLPFC–VS connectivity during negative evaluation. Moreover, RVLPFC activation during all types of feedback processing and left VS activation during negative feedback processing was greater for participants with stable-state self-esteem. These findings implicate neurocognitive mechanisms underlying emotion regulation in the self-enhancement motive and highlight a pathway through which self-enhancement may restore feelings of self-worth during threatening situations. 相似文献
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Khaled Ahmed Mansour Ahmed Elbermawi Ahmed A. Al-Karmalawy Mohamed-Farid Lahloub Mona El-Neketi 《Pharmaceutical biology》2022,60(1):1374
ContextTraditionally, Oleaceae plants are used to treat many diseases, such as rheumatism, hypercholesterolaemia, or ulcers.ObjectivesTo investigate the cytotoxic potential of Jasminum humile L., Jasminum grandiflorum L., and Olea europaea L. (Oleaceae) extracts against selected human cancer cells lines, followed by a phytochemical investigation of the most potent one.Materials and methodsThe 95% ethanol extracts of aerial parts of three oleaceous plants were examined for their cytotoxicity against HepG-2, MCF-7, and THP-1 cell lines using MTT assay and doxorubicin (positive control). J. humile was bio-selected and submitted to bio-guided fractionation. Chromatographic workup of ethyl acetate and n-butanol fractions afforded two new compounds; 1-methoxyjasmigenin (1) and 1-methyl-9-aldojasmigenin (2), along with five known ones (3–7). Structures were unambiguously elucidated using 1D/2D NMR and ESI-HRMS. Isolated compounds were assessed for their anti-proliferative potential, and both selectivity index and statistical significance were determined. Molecular docking was conducted against the Mcl-1 receptor using (AZD5991) as a standard.ResultsJasmoside (5) was the most potent anticancer compound showing IC50 values of 66.47, 41.32, and 27.59 µg/mL against HepG-2, MCF-7, and THP-1 cell lines, respectively. Moreover, isojasminin (4) exhibited IC50 values of 33.49, 43.12, and 51.07 µg/mL against the same cell lines, respectively. Interestingly, 5 exhibited the highest selectivity index towards MCF-7 and THP-1, even greater than doxorubicin. Molecular docking results were in full agreement with the MTT assay and the proposed SAR.ConclusionIn this study, two new compounds were purified. The biological activity highlighted jasmoside (5) as a lead anticancer drug for further future investigation. 相似文献
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Einas S Elwali Ahmed O Almobarak Mona A Hassan Amir A Mahmoou Heitham Awadall Mohamed H Ahmed 《国际眼科》2017,10(6):948-954
AIM: To assess the frequency and associated risk factors of diabetic retinopathy among Sudanese individuals with diabetes attending Makka Eye complex in Khartoum, Sudan.
METHODS: The cross sectional hospital based study recruited 316 individuals with diabetes from Makkah Eye Complex Retina Clinic. Standard questionnaire was used to collect demographic data, medical history and life style characteristics. Blood samples were taken to measure HbA1c and lipid profile. Fundus and slit lamp examination were performed for screening of diabetic retinopathy.
RESULTS: Among 316 participants, 187 (59.2%) were males and 129 (40.8%) were females. The mean age of participants was 58.7±10.5y. The overall frequency of retinopathy was 261 (82.6%). The percentages of the total participants with proliferative diabetic retinopathy (PDR) were 126 (39.9%) and non-proliferative diabetic retinopathy (NPDR) were 135 (42.7%). Importantly, duration of diabetes mellitus (DM) (72.2% of more than 10y), being on oral hypoglycaemic drugs (versus insulin), and hypertension were all significant risk factors for diabetic retinopathy (P=0.00, 0.01 and 0.00 respectively). Complications of diabetes like diabetic foot (17.7%), history of amputation (6.7%) and clinically significant macular edema (CSME) (47.4%) of the eyes were all significant risk factors (P<0.05). Logistic regression analysis showed that duration of diabetes, hypertension and CSME were found to be absolute risk factors (P=0.007, 0.003 and 0.000 respectively). Duration of DM of more than 10y have more than double risk (OR=2.8), while having hypertension triples the risk of retinopathy (OR=3.1).
CONCLUSION: High rates of diabetic retinopathy are noted among individuals with diabetes attending Makkah Eye hospital in capital Khartoum. Urgent strategies are needed to monitor and treat hypertension and optimize diabetes control in individuals with diabetes. More investment in diabetes services is urgently needed. 相似文献
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In this work, a magnetic H3PW12O40/Fe3O4/MIL-88A (Fe) rod-like nanocomposite as a stable and effective ternary adsorbent was fabricated by the hydrothermal method and utilized for the removal of ciprofloxacin (CIP), tetracycline (TC) and organic dyes from aqueous solution. Characterization of the magnetic nanocomposite was accomplished by FT-IR, XRD, Raman spectroscopy, SEM, EDX, TEM, VSM, BET specific surface area and zeta potential analyses. The influencing factors on the adsorption potency of the H3PW12O40/Fe3O4/MIL-88A (Fe) rod-like nanocomposite including initial dye concentration, temperature and adsorbent dose were studied. The maximum adsorption capacities of H3PW12O40/Fe3O4/MIL-88A (Fe) for TC and CIP were 370.37 mg g−1 and 333.33 mg g−1 at 25 °C, respectively. In addition, the H3PW12O40/Fe3O4/MIL-88A (Fe) adsorbent had high regeneration and reusability capacity after four cycles. In addition, the adsorbent was recovered through magnetic decantation and reused for three consecutive cycles without a considerable reduction in its performance. The adsorption mechanism was mainly ascribed to electrostatic and π–π interactions. According to these results, H3PW12O40/Fe3O4/MIL-88A (Fe) can act as a reusable effective adsorbent for the fast elimination of tetracycline (TC), ciprofloxacin (CIP) and cationic dyes from aqueous solutions.A magnetic Fe3O4/MIL-88A Fe rod-like nanocomposite containing H3PW12O40 was fabricated and applied as a new magnetically recoverable ternary adsorbent to remove antibiotics and dyes from aqueous solutions. 相似文献
37.
Herein, a series of vanillin-crosslinked chitosan (Vn-CS) nanocomposites (NCs) containing various contents of ZnO nanoparticles (NPs) was prepared and characterized via FTIR spectroscopy, XRD, TGA, SEM and TEM. Changing the weight% of ZnO NPs in the prepared NCs resulted in an improvement in their antibacterial activity against Gram-negative and Gram-positive bacteria strains compared with the unmodified CS, and the encapsulation efficiency of 5-fluorouracil (5-FU) was found to be in the range of 61.4–69.2%. Subsequently, the release of 5-FU was monitored utilizing the mesoporous ZrO2–Co3O4 NPs modified carbon paste sensor via the square-wave adsorptive anodic stripping voltammetry (SW-AdASV) technique. Also, the release mechanism of 5-FU from each NC was studied by applying the zero-order, first-order, Hixson–Crowell and Higuchi models to the experimental results. The cytotoxicity of prepared NCs and 5-FU-encapsulated NCs was evaluated against the HePG-2, MCF-7 and HCT-116 cancer cell lines, in addition to the WI-38 and WISH normal cell lines using the MTT assay. Notably, 5-FU/CV10 NC exhibited the highest antitumor activity towards all tested cancer cell lines and a moderate activity against WI-38 and WISH normal cell lines with IC50 values of 28.02 ± 2.5 and 31.65 ± 2.7 μg mL−1, respectively. The obtained nanocomposites exhibited suitable selectivity with minimum toxicity against normal cells.Herein, a series of vanillin-crosslinked chitosan (Vn-CS) nanocomposites (NCs) containing various contents of ZnO nanoparticles (NPs) was prepared and characterized via FTIR spectroscopy, XRD, TGA, SEM and TEM. 相似文献
38.
IntroductionPedagogical workshop planning is challenging especially when we aim to promote a reflective practice of the tutees. This practice has been widely discussed in the literature without a real consensus. Some authors reported oral exercises or anecdotes, other described writings or even storytelling. The aim of the authors was to describe the different steps performed by the tutors and to assess the tutees’ satisfaction.Material and methodsThis was a pilot study dealing with the use of the prospective strategy principles in order to plan a pedagogical workshop. Included participants were early academic teacher trainees.ResultsThe authors illustrated how they planned a pedagogical workshop using the prospective strategy and highlighted the satisfaction of the tutees.ConclusionProspective strategy is mainly used in economic field in order to change the future of the companies by acting on different intervening factors. Associating prospective strategy to pedagogical principles hasn’t been reported in the medical literature and seems to be available in order to induce reflective practice. 相似文献
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