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991.
Reliability of Clinician-Based (GRBAS and CAPE-V) and Patient-Based (V-RQOL and IPVI) Documentation of Voice Disorders 总被引:4,自引:0,他引:4
Michael P. Karnell Sarah D. Melton Jana M. Childes Todd C. Coleman Scott A. Dailey Henry T. Hoffman 《Journal of voice》2007,21(5):576-590
This study examined the reliability of two methods for documenting voice quality by clinicians and compared the methods for documenting patients' perceptions of voice quality. It involved a prospective reliability study and a retrospective chart review. Reliability of two clinician-based voice assessment protocols-Grade, Roughness, Breathiness, Asthenia, Strain (GRBAS) and Consensus Auditory Perceptual Evaluation-Voice (CAPE-V)-was evaluated. These two protocols were then compared after use in voice assessments of 42 males and 61 females performed by a certified speech-language pathologist specializing in the assessment of voice disorders. In addition, two patient-based scales (Voice Related Quality of Life, or V-RQOL, and Iowa Patient's Voice Index, or IPVI) obtained from the same patients were compared with each other and with the clinician-based scales. Reliability of clinicians' ratings of overall severity of dysphonia using GRBAS and CAPE-V scales was very good (r>0.80). Agreement between V-RQOL Total scores and IPVI ratings of the patient's perceptions of impact of dysphonia was less strong (Spearman's r=-0.76). There was relatively weak agreement between patient-based and clinician-based scales. Clinician's perceptions of dysphonia appeared to be reliable and unaffected by rating tool, as indicated by the high level of agreement between the two rating systems when they were used together. The CAPE-V system appeared to be more sensitive to small differences within and among patients than the GRBAS system. The V-RQOL and IPVI approaches to documenting patient's perceptions of dysphonia agreed less well possibly due to differences in patient dependence on voice and on interpretation of the rating tool items. The differences between clinician-based and patient-based data support the conclusion that clinicians and patients experience and consider dysphonia very differently. 相似文献
992.
Francesca Gado Rebecca Ferrisi Sarah Di Somma Fabiana Napolitano Kawthar A. Mohamed Lesley A. Stevenson Simona Rapposelli Giuseppe Saccomanni Giuseppe Portella Roger G. Pertwee Robert B. Laprairie Anna Maria Malfitano Clementina Manera 《Molecules (Basel, Switzerland)》2022,27(9)
1,8-naphthyridine-3-carboxamide structures were previously identified as a promising scaffold from which to obtain CB2R agonists with anticancer and anti-inflammatory activity. This work describes the synthesis and functional characterization of new 1,8-naphthyridin-2(1H)-one-3-carboxamides with high affinity and selectivity for CB2R. The new compounds were able to pharmacologically modulate the cAMP response without modulating CB2R-dependent β-arrestin2 recruitment. These structures were also evaluated for their anti-cancer activity against SH-SY5Y and SK-N-BE cells. They were able to reduce the cell viability of both neuroblastoma cancer cell lines with micromolar potency (IC50 of FG158a = 11.8 μM and FG160a = 13.2 μM in SH-SY5Y cells) by a CB2R-mediated mechanism. Finally, in SH-SY5Y cells one of the newly synthesized compounds, FG158a, was able to modulate ERK1/2 expression by a CB2R-mediated effect, thus suggesting that this signaling pathway might be involved in its potential anti-cancer effect. 相似文献
993.
Maya Sarah Isti Madinah Hasibuan Erni Misran Seri Maulina 《Molecules (Basel, Switzerland)》2022,27(19)
Optimization of pectin extraction from cocoa pod husk was carried out to examine independent variables that affect the quality of pectin obtained and determine the best conditions for the extraction process. In this study, three independent variables thought to contribute to microwave-assisted pectin extraction were used, namely, extraction time (20, 25, and 30 min), microwave power (180, 300, and 450 W), and citric acid concentration (2.5%, 5%, and 10%). Response surface methodology was applied using central composite design (CCD) to examine the effect of independent variables on the parameter measured. Among the seven parameters measured, namely, yield, temperature, moisture content, ash content, equivalent weight, methoxyl content, and galacturonic acid content, the statistical analysis test showed that the model equations that were suitable for predicting response values were temperature, moisture content, and ash content. Therefore, the optimization of conditions was only reviewed for these three parameters. Optimization results concluded that the factors that had the most significant effect on temperature, moisture content, and ash content were extraction time and microwave power. Optimal conditions for pectin extraction were at 30 min extraction time, 450 W microwave power, and 10% solvent concentration, resulting in a temperature of 104 °C, moisture content of 6%, and ash content of 8%. Other parameter values measured under these conditions were a yield of 21.10%, equivalent weight of 602.40 mg/mol, methoxyl content of 6.07%, and galacturonic acid content of 72.86%. Pectin extracted from cocoa pod husk using this method has the potential to be further applied, especially in the food and pharmaceutical industries. 相似文献
994.
Hailong Zhang Shiqi Hong Sarah Si Kai Tan Tao Peng Lucas Yuan Hao Goh Kwan Hang Lam Keat Theng Chow Rajeev Gokhale 《Molecules (Basel, Switzerland)》2022,27(19)
Polysorbates (PS 20 and PS 80) are the most widely used surfactants in biopharmaceutical formulations to protect proteins from denaturation, aggregation, and surface adsorption. To date, around 70% of marketed therapeutic antibodies contain either PS 20 or PS 80 in their formulations. However, polysorbates are chemically diverse mixtures, which are prone to degradation by oxidation and hydrolysis to produce peroxides and fatty acids, which, in turn, induce protein oxidation, aggregation, and insoluble particle formation. These will negatively impact protein quality and stability. Thus, polysorbate degradation has emerged as one of the major challenges in the development and commercialization of therapeutic protein products. KLEPTOSE® HPβCD (hydroxypropyl beta-cyclodextrin), a new multifunctional excipient, has been shown to provide protein stabilization functions in biopharmaceutical downstream processes and in their final formulations. This study aims to evaluate HPβCD, a new molecule of its class, against polysorbates as a stabilizer in biologics formulations. In this study, the chemical stability of KLEPTOSE® HPβCDs is compared with polysorbates (20 and 80) under various stress conditions. When subjected to heat stress, HPβCDs show little change in product recovery (90.7–100.7% recovery for different HPβCDs), while polysorbates 20 and 80 show significant degradation, with only 11.5% and 7.3% undegraded product remaining, respectively. When subjected to other chemical stressors, namely, autoclave, light, and oxidative stresses, HPβCD remains almost stable, while polysorbates show more severe degradation, with 95.5% to 98.8% remaining for polysorbate 20 and 85.5% to 97.4% remaining for polysorbate 80. Further, profiling characterization and degradation analysis reveal that chemical structures of HPβCDs remain intact, while polysorbates undergo significant hydrolytic degradation and oxidation. Lastly, the physicochemical stability of monoclonal antibodies in formulations is investigated. When subjected to light stress, adalimumab, as a model mAb, formulated in the presence of HPβCD, shows a significant decrease in protein aggregation, and superior monomer and total protein recovery compared to PS 80-containing formulations. HPβCD also reduces both agitation and thermal stress-induced protein aggregation and prevents subvisible particle formation compared to PS 80. 相似文献
995.
Hassan H. Hammud Sarah A. Maache Nasreen Al Otaibi Nadeem S. Sheikh 《Molecules (Basel, Switzerland)》2022,27(21)
The corrosion inhibition effect of the three extracts from Harmal roots (HRE), leaves (HLE), and flowers (HFE) were studied for carbon steel corrosion inhibition in 0.25 M H2SO4 solution. The electrochemical impedance study indicated that the three types of extracts decreased corrosion effectively through a charge transfer mechanism. Harmal roots and leaf extracts showed inhibition values of 94.1% and 94.2%, while it was 88.7% for Harmal flower extract at the inhibitor concentration of 82.6 ppm. Potentiodynamic polarization data revealed that Harmal extracts acted through predominant cathodic type inhibition. Both the corrosion current density and corrosion rate decreased significantly in the presence of Harmal extracts compared to blank solution. The corrosion rate (mpy) value was 63.3, 86.1, and 180.7 for HRE, HLE, and HFE, respectively. The adsorption-free energy change ΔGads (kJ·mol−1) values calculated from the Langmuir adsorption isotherm plots were for HRE (−35.08), HLE (−33.17), and HFE (−33.12). Thus, corrosion inhibition occurred due to the adsorption of Harmal extract on the carbon steel surface via the chemisorption mechanism. Moreover, a computational investigation using B3LYP/6-311G++(d,p) basis set in both gaseous and aqueous phases was performed for the major alkaloids (1–8) present in the Harmal extract. 相似文献
996.
Stephen A. Matlin Sarah E. Cornell Alain Krief Henning Hopf Goverdhan Mehta 《Chemical science》2022,13(40):11710
Recent assessments alarmingly indicate that many of the world''s leading chemicals are transgressing one or more of the nine planetary boundaries, which define safe operating spaces within which humanity can continue to develop and thrive for generations to come. The unfolding crisis cannot be ignored and there is a once-in-a-century opportunity for chemistry – the science of transformation of matter – to make a critical difference to the future of people and planet. How can chemists contribute to meeting these challenges and restore stability and strengthen resilience to the planetary system that humanity needs for its survival? To respond to the wake-up call, three crucial steps are outlined: (1) urgently working to understand the nature of the looming threats, from a chemistry perspective; (2) harnessing the ingenuity and innovation that are central to the practice of chemistry to develop sustainable solutions; and (3) transforming chemistry itself, in education, research and industry, to re-position it as ‘chemistry for sustainability’ and lead the stewardship of the world''s chemical resources. This will require conservation of material stocks in forms that remain available for use, through attention to circularity, as well as strengthening engagement in systems-based approaches to designing chemistry research and processes informed by convergent working with many other disciplines.Chemistry, the science of transformation of matter, is fundamental to achieving sustainability through ensuring biogeochemical flows do not transgress planetary boundaries. This requires urgent changes in chemistry education, research and industry. 相似文献
997.
Philip Wiredu Addo Sai Uday Kumar Reddy Sagili Samuel Eichhorn Bilodeau Frederick-Alexandre Gladu-Gallant Douglas A. MacKenzie Jennifer Bates Garnet McRae Sarah MacPherson Maxime Paris Vijaya Raghavan Valrie Orsat Mark Lefsrud 《Molecules (Basel, Switzerland)》2022,27(24)
Limited studies have explored different extraction techniques that improve cannabis extraction with scale-up potential. Ultrasound-assisted and microwave-assisted extraction were evaluated to maximize the yield and concentration of cannabinoids and terpenes. A central composite rotatable design was used to optimize independent factors (sample-to-solvent ratio, extraction time, extraction temperature, and duty cycle). The optimal conditions for ultrasound- and microwave-assisted extraction were the sample-to-solvent ratios of 1:15 and 1:14.4, respectively, for 30 min at 60 °C. Ultrasound-assisted extraction yielded 14.4% and 14.2% more oil and terpenes, respectively, compared with microwave-assisted extracts. Ultrasound-assisted extraction increased cannabinoid concentration from 13.2–39.2%. Considering reference ground samples, tetrahydrocannabinolic acid increased from 17.9 (g 100 g dry matter−1) to 28.5 and 20 with extraction efficiencies of 159.2% and 111.4% for ultrasound-assisted and microwave-assisted extraction, respectively. Principal component analyses indicate that the first two principal components accounted for 96.6% of the total variance (PC1 = 93.2% and PC2 = 3.4%) for ultrasound-assisted extraction and 92.4% of the total variance (PC1 = 85.4% and PC2 = 7%) for microwave-assisted extraction. Sample-to-solvent ratios significantly (p < 0.05) influenced the secondary metabolite profiles and yields for ultrasound-assisted extracts, but not microwave-assisted extracts. 相似文献
998.
Philip Wiredu Addo Sai Uday Kumar Reddy Sagili Samuel Eichhorn Bilodeau Frederick-Alexandre Gladu-Gallant Douglas A. MacKenzie Jennifer Bates Garnet McRae Sarah MacPherson Maxime Paris Vijaya Raghavan Valrie Orsat Mark Lefsrud 《Molecules (Basel, Switzerland)》2022,27(24)
Efficient cannabis biomass extraction can increase yield while reducing costs and minimizing waste. Cold ethanol extraction was evaluated to maximize yield and concentrations of cannabinoids and terpenes at different temperatures. Central composite rotatable design was used to optimize two independent factors: sample-to-solvent ratio (1:2.9 to 1:17.1) and extraction time (5.7 min–34.1 min). With response surface methodology, predicted optimal conditions at different extraction temperatures were a cannabis-to-ethanol ratio of 1:15 and a 10 min extraction time. With these conditions, yields (g 100 g dry matter−1) were 18.2, 19.7, and 18.5 for −20 °C, −40 °C and room temperature, respectively. Compared to the reference ground sample, tetrahydrocannabinolic acid changed from 17.9 (g 100 g dry matter−1) to 15, 17.5, and 18.3 with an extraction efficiency of 83.6%, 97.7%, 102.1% for −20 °C, −40 °C, and room temperature, respectively. Terpene content decreased by 54.1% and 32.2% for extraction at −20 °C and room temperature, respectively, compared to extraction at −40 °C. Principal component analysis showed that principal component 1 and principal component 2 account for 88% and 7.31% of total variance, respectively, although no significant differences in cold ethanol extraction at different temperatures were observed. 相似文献
999.
James W. Favell Kerry L. Wilkinson Ieva Zigg Sarah M. Lyons Renata Ristic Carolyn J. Puglisi Eric Wilkes Randell Taylor Duane Kelly Greg Howell Marianne McKay Lucky Mokwena Tim Plozza Pei Zhang AnhDuyen Bui Ian Porter Orrin Frederick Jasha Karasek Colleen Szeto Bruce S. Pan Steve Tallman Beth Anne McClure Hui Feng Eric Herv Anita Oberholster Wesley F. Zandberg Matthew Noestheden 《Molecules (Basel, Switzerland)》2022,27(15)
Vineyard exposure to wildfire smoke can taint grapes and wine. To understand the impact of this taint, it is imperative that the analytical methods used are accurate and precise. This study compared the variance across nine commercial and research laboratories following quantitative analysis of the same set of smoke-tainted wines. In parallel, correlations between the interlaboratory consensus values for smoke-taint markers and sensory analyses of the same smoke-tainted wines were evaluated. For free guaiacol, the mean accuracy was 94 ± 11% in model wine, while the free cresols and 4-methylguaiacol showed a negative bias and/or decreased precision relative to guaiacol. Similar trends were observed in smoke-tainted wines, with the cresols and glycosidically bound markers demonstrating high variance. Collectively, the interlaboratory results show that data from a single laboratory can be used quantitatively to understand smoke-taint. Results from different laboratories, however, should not be directly compared due to the high variance between study participants. Correlations between consensus compositional data and sensory evaluations suggest the risk of perceivable smoke-taint can be predicted from free cresol concentrations, overcoming limitations associated with the occurrence of some volatile phenols, guaiacol in particular, as natural constituents of some grape cultivars and of the oak used for barrel maturation. 相似文献
1000.
Many natural and artificial systems are subject to some sort of delay, which can be in the form of a single discrete delay or distributed over a range of times. Here, we discuss the impact of this distribution on (thermo-)dynamical properties of time-delayed stochastic systems. To this end, we study a simple classical model with white and colored noise, and focus on the class of Gamma-distributed delays which includes a variety of distinct delay distributions typical for feedback experiments and biological systems. A physical application is a colloid subject to time-delayed feedback control, which is, in principle, experimentally realizable by co-moving optical traps. We uncover several unexpected phenomena in regard to the system’s linear stability and its thermodynamic properties. First, increasing the mean delay time can destabilize or stabilize the process, depending on the distribution of the delay. Second, for all considered distributions, the heat dissipated by the controlled system (e.g., the colloidal particle) can become negative, which implies that the delay force extracts energy and entropy of the bath. As we show here, this refrigerating effect is particularly pronounced for exponential delay. For a specific non-reciprocal realization of a control device, we find that the entropic costs, measured by the total entropy production of the system plus controller, are the lowest for exponential delay. The exponential delay further yields the largest stable parameter regions. In this sense, exponential delay represents the most effective and robust type of delayed feedback. 相似文献