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151.
152.
Clint Hansen Gentiane Venture Nasser Rezzoug Philippe Gorce Brice Isableu 《Journal of biomechanics》2014
Over the last decades a variety of research has been conducted with the goal to improve the Body Segment Inertial Parameters (BSIP) estimations but to our knowledge a real validation has never been completely successful, because no ground truth is available. The aim of this paper is to propose a validation method for a BSIP identification method (IM) and to confirm the results by comparing them with recalculated contact forces using inverse dynamics to those obtained by a force plate. Furthermore, the results are compared with the recently proposed estimation method by Dumas et al. (2007). Additionally, the results are cross validated with a high velocity overarm throwing movement. Throughout conditions higher correlations, smaller metrics and smaller RMSE can be found for the proposed BSIP estimation (IM) which shows its advantage compared to recently proposed methods as of Dumas et al. (2007). The purpose of the paper is to validate an already proposed method and to show that this method can be of significant advantage compared to conventional methods. 相似文献
153.
154.
McGee KC Harte AL da Silva NF Al-Daghri N Creely SJ Kusminski CM Tripathi G Levick PL Khanolkar M Evans M Chittari MV Patel V Kumar S McTernan PG 《PloS one》2011,6(6):e20287
Visfatin has been proposed as an insulin-mimicking adipocytokine, predominantly secreted from adipose tissue and correlated with obesity. However, recent studies suggest visfatin may act as a proinflammatory cytokine. Our studies sought to determine the significance of this adipocytokine and its potential role in the pathogenesis of T2DM. Firstly, we examined the effects of diabetic status on circulating visfatin levels, and several other adipocytokines, demonstrating that diabetic status increased visfatin*, TNF-α*** and IL-6*** compared with non-diabetic subjects (*p<0.05, **p<0.01, ***p<0.001, respectively). We then assessed the effects of an insulin sensitizer, rosiglitazone (RSG), in treatment naïve T2DM subjects, on circulating visfatin levels. Our findings showed that visfatin was reduced post-RSG treatment [vs. pre-treatment (*p<0.05)] accompanied by a reduction in HOMA-IR**, thus implicating a role for insulin in visfatin regulation. Further studies addressed the intracellular mechanisms by which visfatin may be regulated, and may exert pro-inflammatory effects, in human abdominal subcutaneous (Abd Sc) adipocytes. Following insulin (Ins) and RSG treatment, our in vitro findings highlighted that insulin (100 nM), alone, upregulated visfatin protein expression whereas, in combination with RSG (10 nM), it reduced visfatin*, IKKβ** and p-JNK1/2*. Furthermore, inhibition of JNK protein exacted a significant reduction in visfatin expression (**p<0.01), whilst NF-κB blockade increased visfatin (*p<0.05), thus identifying JNK as the more influential factor in visfatin regulation. Additional in vitro analysis on adipokines regulating visfatin showed that only Abd Sc adipocytes treated with recombinant human (rh)IL-6 increased visfatin protein (*p<0.05), whilst rh visfatin treatment, itself, had no influence on TNF-α, IL-6 or resistin secretion from Sc adipocytes. These data highlight visfatin''s regulation by insulin and RSG, potentially acting through NF-κB and JNK mechanisms, with only rh IL-6 modestly affecting visfatin regulation. Taken together, these findings suggest that visfatin may represent a pro-inflammatory cytokine that is influenced by insulin/insulin sensitivity via the NF-κB and JNK pathways. 相似文献
155.
Elsayed M. Younis Abdel-Wahab A. Abdel-Warith Nasser A. Al-Asgah Soltan A. Elthebite Md Mostafizur Rahman 《Saudi Journal of Biological Sciences》2021,28(3):1860-1866
The study evaluated the nutritional quality and investigated the heavy metals concentration in muscle tissues of five commercially important marine fish species, including brownspotted grouper (Epinephelus chlorostigma), squaretail coralgrouper (Plectropomus areolatus), black pomfret (Parastromateus niger), goldbanded jobfish (Pristipomoides multidens), and blueskin seabream (Polysteganus coeruleopunctatus) from the Red Sea, Jeddah Coast, Saudi Arabia. Significant differences (p < 0.05) were observed in the proximate chemical composition of fish muscles in these species. The highest protein content (17.66 ± 0.58%) was achieved in blueskin seabream while the lowest (15.28 ± 0.46%) was observed in brownspotted grouper. The highest lipid content (2.97 ± 0.45%) was recorded in squaretail coralgrouper while the lowest (1.52 ± 0.26%) was observed in blueskin seabream. Heavy metal concentrations varied significantly within and between fish species under study (p < 0.05). Significant differences in the concentration of heavy metals among fish species were recorded. Results revealed that the bioaccumulation of Cr, Fe, Ni, and Cd in muscles of fish species under study was higher than the standard concentration, but that of Mn, Cu, and Pb were less than the standard concentration recommended in the EU, FAO, and WHO guidelines. In conclusion, these fish species represent a high-quality food source but is unsafe due to the level of certain minerals in their tissues. Results also indicated that the Red Sea environment is contaminated with heavy metals, which was reflected in the tissues of fishes used in this study. 相似文献
156.
Behnam Sadeghi Elham Roshandel Ali Pirsalehi Sepide Kazemi Ghazaleh Sankanian Mohammad Majidi Maryam Salimi Nasser Aghdami Hoda Sadrosadat Sarvenaz Samadi Kochaksaraei Farshid Alaeddini Olle Ringden Abbas Hajifathali 《Journal of cellular and molecular medicine》2021,25(22):10554-10564
Acute respiratory distress syndrome (ARDS) is the most common cause of death in COVID-19 patients. The cytokine storm is the main driver of the severity and magnitude of ARDS. Placenta-derived decidua stromal cells (DSCs) have a stronger immunosuppressive effect than other sources of mesenchymal stromal cells. Safety and efficacy study included 10 patients with a median age of 50 (range 14–68) years with COVID-19-induced ARDS. DSCs were administered 1–2 times at a dose of 1 × 106/kg. End points were safety and efficacy by survival, oxygenation and effects on levels of cytokines. Oxygenation levels increased from a median of 80.5% (range 69–88) to 95% (range 78–99) (p = 0.012), and pulmonary infiltrates disappeared in all patients. Levels of IL-6 decreased from a median of 69.3 (range 35.0–253.4) to 11 (range 4.0–38.3) pg/ml (p = 0.018), and CRP decreased from 69 (range 5–169) to 6 (range 2–31) mg/ml (p = 0.028). Two patients died, one of a myocardial infarction and the other of multiple organ failure, diagnosed before the DSC therapy. The other patients recovered and left the intensive care unit (ICU) within a median of 6 (range 3–12) days. DSC therapy is safe and capable of improving oxygenation, decreasing inflammatory cytokine level and clearing pulmonary infiltrates in patients with COVID-19. 相似文献
157.
J.A. Nasser A. Del Parigi K. Merhige C. Wolper A. Geliebter S.A. Hashim 《Obesity (Silver Spring, Md.)》2013,21(5):976-980
Objective:
The activity of dopamine‐dependent retinal signaling can be assessed using electroretinography. Response of this system to oral food stimulation might provide accessible insight into the brain dopamine response to oral stimuli as retinal dopamine concentration is dependent upon mid brain dopamine concentration was postulated.Design and Methods:
Nine individuals had cone ERG (b wave) response to oral food stimulation and oral methylphenidate (MPH) administration measured on separate days, and completed self reported eating behavior questionnaires.Results:
Significant and similar increases in b wave response to both stimuli (P = 0.012 and P = 0.042, MPH and food, respectively) and significant correlations of the food stimulated b wave amplitude with binge eating related behavior as measured by the Gormally Binge Eating Scale (r = 0.68, P = 0.044) and self‐reported trait hunger as measured by the Stunkard and Messick Three Factor Eating Questionnaire (r = 0.67, P = 0.048) were found.Conclusion:
The significant increase in food stimulated dopamine dependent b wave amplitude and correlation with methylphenidate stimulated b wave amplitude suggest that ERG may offer a relatively inexpensive and accessible methodology for potentially assess dopaminergic responses to food and other externally applied stimuli that have been implicated in the pathogenesis of a number of human diseases. 相似文献158.
Mousa Abkhezr Ali Reza Keramati Seyed Nasser Ostad Jamshid Davoodi Mohammad H. Ghahremani 《Molecular biology reports》2010,37(4):2037-2042
The cell growth is controlled by the interaction of survival and cell growth arrest pathways as well as apoptosis mechanisms
which determine the outcome of cell faith as proliferation or apoptosis. In this study, we have studied the activity of survival
pathways, i.e., Akt and ERK1/2 with regard to XIAP (inhibitor of apoptosis) in serum starved and stimulated conditions. The
HEK-293 cells were cultured in RPMI + 10% FBS. The cells were serum starved by switching to medium with 1% FBS for 24 h and
serum stimulated by changing the medium to 10% FBS following serum starvation. The expression of p-Akt, p-ERK, Akt, ERK and
XIAP was studied in various time points using western blot. The apoptosis was evaluated by DNA condensation using Hoechst
33258 and Caspase-3 assay. In serum starved condition expression of p-Akt and XIAP is very low. Serum stimulation increases
p-Akt and p-ERK within 5 min and sustains a high level for 30 min. The expression of total Akt and ERK1/2 has not changed
significantly for 24 h. XIAP expression starts at 6 h after serum stimulation, reaches to maximum level at 12 h and decreases
to baseline within 24 h. Furthermore, serum starvation for 24 h does not induced apoptosis and DNA condensation. Taken together,
the results indicate that serum activates Akt and ERK pathways earlier than XIAP expression. Furthermore, XIAP expression
is low in serum starvation unlike p-ERK which suggests a survival role for ERK in serums starvation. The expression pattern
of XIAP indicates induction by Akt and/or ERK activation which requires further studies. 相似文献
159.
B Nasser C Morpain B Laude N Latruffe 《Comptes rendus des séances de la Société de biologie et de ses filiales》1988,182(6):565-571
The structural requirements of lecithins analogs for purified D-beta-hydroxybutyrate dehydrogenase activation have been studied with chemically defined phospholipids. It appears that the trimethylamine group of choline can be changed by a pyridinium group. On the other hand, the decrease of density of the positive charges on the liposomes surface obtained by dilution of such bearing molecules with negative or non charged phospholipids increases the enzyme reactivation. Finally, the PAF acether, a lipid mediator, is able to reactivate the enzyme in similar conditions as these obtained with mitochondrial phosphatidylcholines. 相似文献
160.