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181.
Sally L. Elshaer Salma H. Bahram Pranav Rajashekar Rajashekhar Gangaraju Azza B. El-Remessy 《International journal of molecular sciences》2022,23(1)
Mesenchymal stem cells are multipotent stem cells isolated from various tissue sources, including but not limited to bone marrow, adipose, umbilical cord, and Wharton Jelly. Although cell-mediated mechanisms have been reported, the therapeutic effect of MSCs is now recognized to be primarily mediated via paracrine effects through the secretion of bioactive molecules, known as the “secretome”. The regenerative benefit of the secretome has been attributed to trophic factors and cytokines that play neuroprotective, anti-angiogenic/pro-angiogenic, anti-inflammatory, and immune-modulatory roles. The advancement of autologous MSCs therapy can be hindered when introduced back into a hostile/disease environment. Barriers include impaired endogenous MSCs function, limited post-transplantation cell viability, and altered immune-modulatory efficiency. Although secretome-based therapeutics have gained popularity, many translational hurdles, including the heterogeneity of MSCs, limited proliferation potential, and the complex nature of the secretome, have impeded the progress. This review will discuss the experimental and clinical impact of restoring the functional capabilities of MSCs prior to transplantation and the progress in secretome therapies involving extracellular vesicles. Modulation and utilization of MSCs–secretome are most likely to serve as an effective strategy for promoting their ultimate success as therapeutic modulators. 相似文献
182.
Romaina Iqbal Ghazala Rafique Salma Badruddin Rahat Qureshi Katherine Gray-Donald 《Nutrition journal》2006,5(1):18-6
Background
Precise measurements of activity at a population level are important for monitoring trends and evaluating health promotion strategies. Few studies have assessed the measurement of physical activity in developing countries. The aim of this study was to validate the MOSPA (Monica Optional Study of Physical Activity) questionnaire which was developed for the WHO-Monitoring trends and determinants of cardiovasculr disease (MONICA) study sites. 相似文献183.
This work aims at simulation of reactivity induced transients in High Enriched Uranium (HEU) and Low Enriched Uranium (LEU) cores of a typical Material Test research Reactor (MTR) using PARET code. The transient problem was forced through specification of externally inserted reactivity as a function of time. Reactivity insertions are idealized by ramps and steps. Superdelayed-critical transients, superprompt-critical transients and quasistatic transients are selected for the analysis. Ramp and step reactivity functions were employed to simulate these perturbations. The effect of initial power on transient behavior has also been investigated. The low enriched uranium core is analyzed for transients without scram. The magnitudes of maximum reactivity insertions are chosen to be in the range of $0.05 to 2.0 for different reactivity insertion times. Transient simulation with scram reveals that response of both HEU and LEU-cores is similar for selected ‘ramps’ and ‘steps’. The difference is observed in the peak values of power and coolant, clad and fuel temperatures. Trip level is achieved earlier in case of LEU-core. The peak clad temperatures in both LEU and HEU-cores remain below the melting point of aluminum-clad for the selected reactivity insertions. Simulation show that the LEU-core is more sensitive to perturbations at low power as compared to the transients at full power. For reactivity transients at low power level, power rises sharply to a higher peak value. In transients at full power, the peak power barely exceeds the trip level. The power oscillations after the first peak are observed for transients without scram. 相似文献
184.
Salma Bilal 《Electrochimica acta》2007,52(17):5346-5356
Results of in situ UV-vis spectroelectrochemical studies of the electropolymerization of o-phenylenediamine (OPD), m-toluidine (MT) and the copolymerization of OPD with MT are reported. Electropolymerization was performed in aqueous acidic medium at a constant potential of ESCE = 1.0 V at an indium doped tin oxide (ITO) coated glass electrode. The course of homopolymerization was followed for MT and OPD solutions with various monomer concentrations. The spectral characteristics of the mixed solutions were studied at a constant concentration of MT and various concentrations of OPD in the comonomer feed. An absorption band at λ = 497 nm was assigned to the head-to-tail mixed dimer/oligomer resulting from the cross reaction between OPD and MT cation radicals. UV-vis spectra recorded during copolymerization show dependence of the growth of the band at λ = 497 nm on OPD concentration in the feed. At lower OPD feed concentration it appears as the major band in the corresponding spectra. The UV-vis spectra recorded for the copolymer films suggest the incorporation of both monomer units in the copolymer. The FT-IR spectra of the copolymers show the presence of phenazine type structures in the copolymer backbone. 相似文献
185.
Mallika G. C. Alsadoon Abeer Pham Duong Thu Hang Mai Ha Thi Abdullah Salma Prasad P.W.C. Nguyen Tran Quoc Vinh 《Programming and Computer Software》2021,47(5):402-414
Programming and Computer Software - Type 2 Diabetes (T2DM) makes up about 90% of diabetes cases, as well as tough restriction on continuous monitoring and detecting become one of key aspects in... 相似文献
186.
Salma Cheikh-Rouhou Souhail Besbes Basma Hentati Christophe Blecker Claude Deroanne Hamadi Attia 《Food chemistry》2007,101(2):673-681
Physicochemical properties of two Nigella seed varieties, having a Tunisian and Iranian origin, were determined. Physical and chemical analyses of crude oils extracted from the seeds by a cold solvent method were also performed. The following results (on a dry-weight basis) were obtained for Tunisian and Iranian varieties, respectively: protein 26.7% and 22.6%, oil 28.48% and 40.35%, ash 4.86% and 4.41%, and total carbohydrate 40.0% and 32.7%. The major unsaturated fatty acids were linoleic acid (50.3–49.2%), followed by oleic acid (25.0–23.7%), while the main saturated fatty acid was palmitic acid (17.2–18.4%). Myristic, myristoleic, palmitoleic, margaric, margaroleic, stearic, linolenic, arachidic, eicosenoic, behenic and lignoceric acids were also detected. Thermal profiles of both Nigella seed varieties, determined by their DSC melting curves, revealed different thermograms. Sensorial profiles of Tunisian and Iranian seed oils were defined through the CieLab (L∗, a∗, b∗) colour, oxidative stability by Rancimat test and viscosity. Physicochemical properties of the oils for Tunisian and Iranian varieties, respectively, include: saponification number 211 and 217, peroxide value 5.65 and 4.35, iodine index 120 and 101, and an acidity of 22.7% and 18.6%. Results suggested that Nigella seed oil could deserve further consideration and investigation as a potential new multi-purpose product for industrial, cosmetic and pharmaceutical uses. 相似文献
187.
Alexander V Prokhorov Karen Suchanek Hudmon Paul M Cinciripini Salma Marani 《Nicotine & tobacco research》2005,7(6):909-913
Since the early 1980s, investigators have been reporting that adolescent smokers felt "dependent" on cigarettes and that adolescents trying to quit smoking experienced the same withdrawal symptoms observed in adult quitters, including restlessness, insomnia, increased appetite and weight gain, irritability or anger, depression, craving for cigarettes, and trouble concentrating. We hypothesized that most of these symptoms might be attributed to adolescence itself. To investigate this hypothesis, we examined the prevalence of these seven "adult" withdrawal symptoms in a population of adolescent former smokers and never-smokers. Participants were high school students in Houston, Texas, participating in a nested, group-randomized control group study designed to estimate the impact of a CD-ROM intervention for smoking prevention and cessation. We measured differences in symptoms frequency between never-smokers and former smokers, matched in a 2:1 ratio on sex and race/ethnicity, and differences in symptoms among former smokers as a function of time since final quit attempt and prior level of smoking. Only former heavy smokers have shown significantly higher prevalence of withdrawal symptoms compared with never-smokers. Of the seven symptoms assessed, only craving incrementally increased with the intensity of smoking. Overall the individual withdrawal symptoms did not effectively differentiate between 112 never-smokers and 34 former lighter smokers (persons who used to smoke less than "a few cigarettes on most days"). Withdrawal symptoms can reliably differentiate former heavy smokers from light smokers and never-smokers, among adolescents. Because most adolescents tend to be lighter smokers, future tobacco use and cessation studies should interpret adult withdrawal symptoms among adolescents with caution. 相似文献
188.
Issa Korbag Salma Mohamed Saleh 《The International journal of environmental studies》2016,73(2):226-235
The intermolecular interactions of lignin with a hydrophilic polymer, poly (vinyl alcohol) (PVA), were studied using Nuclear Magnetic Resonance (NMR) and FT-IR spectroscopy of PVA/lignin blend fibres prepared by casting method. The structure of polyvinyl alcohol/lignin blended film has also been studied. The FT-IR technique indicates the formation of strong intermolecular hydrogen bonds between the hydroxyl groups of PVA and lignin. 1H and 13C NMR spectra of the blend show extra peaks which confirm the formation of strong intermolecular hydrogen bonds between the hydroxyl groups of PVA and lignin. The results show that there is some specific intermolecular interaction between PVA and lignin. 相似文献
189.
190.
Inflorescence scent samples from nine populations of dioecious Silene otites, a plant pollinated by moths and mosquitoes, were collected by dynamic headspace extraction. Sixty-three scent samples were
analyzed by gas chromatography–mass spectrometry. Out of 38 found, 35 compounds were identified, most of which were monoterpenoids,
fatty acid derivatives, and benzenoids. Phenyl acetaldehyde was the most dominant compound in the majority of samples. The
variability in scent composition was high, and population and sex differences were found. Nevertheless, wind tunnel experiments
proved similar attraction of Culex pipiens pipiens biotype molestus mosquitoes to the inflorescence odor of S. otites of different populations, indicating that different blends are similarly attractive to mosquitoes. The electrophysiological
responses of mosquitoes to the 12 most common and abundant odor compounds of S. otites differed. Linalool oxide (furanoid) and linalool evoked the strongest responses in male and female mosquitoes, and (Z)-3-hexenyl acetate was strongly active in females. Medium responses were evoked in males by (Z)-3-hexenyl acetate, in females by benzaldehyde and methyl salicylate, and in both sexes by lilac aldehyde, lilac alcohol,
and linalool oxide (pyranoid). 相似文献