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91.

Background

Representative surveys collecting weight, height and MUAC are used to estimate the prevalence of acute malnutrition. The results are then used to assess the scale of malnutrition in a population and type of nutritional intervention required. There have been changes in methodology over recent decades; the objective of this study was to determine if these have resulted in higher quality surveys.

Methods

In order to examine the change in reliability of such surveys we have analysed the statistical distributions of the derived anthropometric parameters from 1843 surveys conducted by 19 agencies between 1986 and 2015.

Results

With the introduction of standardised guidelines and software by 2003 and their more general application from 2007 the mean standard deviation, kurtosis and skewness of the parameters used to assess nutritional status have each moved to now approximate the distribution of the WHO standards when the exclusion of outliers from analysis is based upon SMART flagging procedure. Where WHO flags, that only exclude data incompatible with life, are used the quality of anthropometric surveys has improved and the results now approach those seen with SMART flags and the WHO standards distribution. Agencies vary in their uptake and adherence to standard guidelines. Those agencies that fully implement the guidelines achieve the most consistently reliable results.

Conclusions

Standard methods should be universally used to produce reliable data and tests of data quality and SMART type flagging procedures should be applied and reported to ensure that the data are credible and therefore inform appropriate intervention. Use of SMART guidelines has coincided with reliable anthropometric data since 2007.
  相似文献   
92.

Background

Many young adults, specifically those with a diagnosis of autism spectrum disorder (ASD), do not meet the national physical activity (PA) guidelines. One way to address this problem may be to examine the factors that motivate individuals to engage in PA. However, the majority of current literature does not consider the unique characteristics of individuals with ASD, which may influence their motivation.

Objective

The purpose of this research was to examine Self-Determination Theory predictors for PA for young adults with ASD.

Methods

Respondents included 143 young adults with ASD who completed a survey pertaining to their motivational process to engage in physical activity, based on self-determination theory variables.

Results

Goodness of fit indices reported from a path analysis suggests the current data closely align with the self-determination theory (χ2 (3, N?=?143)?=?11.99, p?>?.01, GFI?=?0.97, NFI?=?0.95, CFI?=?. 96, RMSEA?=?0.15). The three basic psychological needs explained 39% of the variance within respondents' self-determined motivation, and self-determined motivation explained 8% of the variance in PA levels.

Conclusions

These findings support utilizing the self-determination theory within health promotion efforts for young adults with ASD. Practitioners should focus on enhancing the perceived basic psychological needs of young adults within physical activity settings.  相似文献   
93.
The purpose of this study is to document the potential impacts on indoor air quality associated with different types of building materials (wall and floor finishes) through the development of an Indoor Air Quality index. The study first identifies pollutant sources and their corresponding health impacts due to short-term and long-term exposures. The study also quantifies levels of certain pollutants within a steady-state controlled environment, comparing the results of this study with previous studies conducted in different regions. It also proposes an IAQ index as an assessment tool which can be utilized preoccupancy. The field studies were conducted in residential buildings during January and February in Cairo to monitor volatile organic compounds (VOCs), formaldehyde (HCHO), ammonia (NH3), radon gas, and particulate matter (PM). The indoor air was monitored in nine locations: four during the construction process and five following completion of construction. For this investigation, three rooms under construction within a Cairene building site were utilized to test the finishing materials. Chemical analysis and direct reading devices were used for air sampling and monitoring. The results revealed that the concentration of some pollutants decreased within the first year of construction, while others remained above target limits. The results of this study offer recommendations for engineers regarding the selection of appropriate materials through the implementation of source control strategies and an IAQ index which can be used as an assessment tool to ensure that the Indoor Air Quality meets recommended standards. Based on the conclusions and limitations of this study, recommendations for future work are documented such as the screening of materials and monitoring of Indoor Air Quality.  相似文献   
94.
Poor air quality and related health impacts are still an issue in many cities and regions worldwide. Integrated assessment models (IAMs) can support the design of measures to reduce the emissions of precursors affecting air pollution. In this study, we apply the SHERPA (screening for high emission reduction potentials for air quality) model to compare spatial and sectoral emission reductions, given country-scale emission targets. Different approaches are tested: (a) country ”uniform” emission reductions, (b) emission reductions targeting urban areas, (c) emission reductions targeting preferential sectors. As a case study, we apply the approaches to the implementation of the National Emission Ceiling Directive. Results are evaluated in terms of the reduction in average population exposure to PM2.5 overall in a country and in its main cities. Results indicate that the reduction of population exposure to PM2.5 highly depends on the way emission reductions are implemented. This work also shows the usefulness of the SHERPA model to support national authorities implementing national emission reduction targets while, at the same time, addressing their local air quality issues.  相似文献   
95.

Purpose

This article describes preclinical development of cell-based medicinal products for European markets and discusses European regulatory mechanisms open to developers to aid successful product development. Cell-based medicinal products are diverse, including cells that are autologous or allogeneic, have been genetically modified, or not, or expanded ex vivo, and applied systemically or to an anatomical site different to that of their origin; comments applicable to one product may not be applicable to others, so bespoke development is needed, for all elements - quality, preclinical and clinical.

Methods

After establishing how the product is produced, proof of potential for therapeutic efficacy, and then safety, of the product need to be determined. This includes understanding biodistribution, persistence and toxicity, including potential for malignant transformation. These elements need to be considered in the context of the intended clinical development.

Results

This article describes regulatory mechanisms available to developers to support product development that aim to resolve scientific issues prior to marketing authorization application, to enable patients to have faster access to the product than would otherwise be the case.

Conclusions

Developers are encouraged to be aware of both the scientific issues and regulatory mechanisms to ensure patients can be supplied with these products.
  相似文献   
96.

Purpose

Biotherapeutics can be susceptible to oxidation during manufacturing and storage. Free L-methionine is known to protect methionine residues in proteins from oxidation. Similarly, free tryptophan and other indole derivatives have been shown to protect tryptophan residues from oxidation. N-acetyl-DL-tryptophan was previously identified as a potentially superior antioxidant to tryptophan as it has a lower oxidation potential and produces less peroxide upon light exposure. This study sought to confirm the antioxidant efficacy and safety of N-acetyl-DL-tryptophan and L-methionine as formulation components for biotherapeutic drugs.

Methods

Antibodies were subjected to AAPH and light exposure in the presence of N-acetyl-DL-tryptophan and L-methionine. Oxidation in relevant CDR and Fc residues was quantified by peptide map. In silico, in vitro, and in vivo studies were performed to evaluate the safety of N-acetyl-DL-tryptophan and L-methionine.

Results

Peptide mapping demonstrated that N-acetyl-DL-tryptophan was effective at protecting tryptophans from AAPH stress, and that the combination of N-acetyl-DL-tryptophan and L-methionine protected both tryptophan and methionine from AAPH stress. The safety assessment suggested an acceptable safety profile for both excipients.

Conclusions

N-acetyl-tryptophan and L-methionine effectively reduce the oxidation of susceptible tryptophan and methionine residues in antibodies and are safe for use in parenteral biotherapeutic formulations.
  相似文献   
97.

Purpose

Accurate quantification of the intact proteins, antibodies or peptides and their impurities without interaction to silanols of HPLC column.

Methods

Hydroxypropyl ß Cyclodextrin (HPCD) is added in the mobile phase at different concentrations. Different commercial SEC-HPLC columns and biologics with a molecular weight ranging from 5.8 kDa to 150kDa were assessed with and without cyclodextrin.

Results

Addition of non-ionic sugars such as Hydroxypropyl ß Cyclodextrin in the mobile phase, resulted improved peak performance such as theoretical plates, peak resolution, peak width, peak height, and improved quantification of aggregates in biologics such as antibodies Humira and Actemra, and peptides such as insulin. There is an increase in peak height, reduced retention time, increased plate and reduced peak width with increasing concentration of cyclodextrin studied.

Discussion

High ionic strength, basic amino acids such as arginine, organic solvents (with a concentration low enough not to precipitate protein), sodium perchlorate and ion pairing agents in the mobile phase used for separation of peptides, proteins and antibodies to prevent silanol interaction. These commonly used solutions are not always successful, as they not only interact with the biologic, but are sometimes, not compatible. The non-ionic cyclodextrin itself does not cause protein aggregation but prevents the nonspecific binding or interaction of protein itself and thereby allowing for improved resolution, and accurate quantification of aggregates in antibodies, and peptides. The data on the separation in presence of cyclodextrin in the mobile phase showed higher peak resolution, improved peak shape, accurate apparent molecular weight, improved efficiency, and less peak tailing for biological products.

Conclusion

Hydroxypropyl ß Cyclodextrin in the mobile phase, resulted improved SEC-HPLC resolution, and quantitation of aggregates in biologics by preventing the interaction of biologics to silanol of the commercial SEC-HPLC columns.
  相似文献   
98.
We demonstrate the coating of tablets using an injection molding (IM) process that has advantage of being solvent free and can provide precision coat features. The selected core tablets comprising 10% w/w griseofulvin were prepared by an integrated hot melt extrusion-injection molding (HME-IM) process. Coating trials were conducted on a vertical injection mold machine. Polyethylene glycol and polyethylene oxide based hot melt extruded coat compositions were used. Tablet coating process feasibility was successfully demonstrated using different coating mold designs (with both overlapping and non-overlapping coatings at the weld) and coat thicknesses of 150 and 300?μm. The resultant coated tablets had acceptable appearance, seal at the weld, and immediate drug release profile (with an acceptable lag time). Since IM is a continuous process, this study opens opportunities to develop HME-IM continuous processes for transforming powder to coated tablets.  相似文献   
99.
During the past decades, lipid nanocarriers are gaining momentum with their multiple advantages for the management of skin diseases. Lipid nanocarriers enable to target the therapeutic payload to deep skin layers or even to reach the blood circulation making them a promising cutting-edge technology.Lipid nanocarriers refer to a large panel of drug delivery systems. Lipid vesicles are the most conventional, known to be able to carry lipophilic and hydrophilic active agents. A variety of lipid vesicles with high flexibility and deformability could be obtained by adjusting their composition; namely ethosomes, transfersomes and penetration enhancer lipid vesicles which achieve the best results in term of skin permeation. Others are designed with the objective to perform higher encapsulation rate and higher stability, such as solid lipid nanoparticles and nanostructured lipid nanocarriers.In this review, we attempted to give an overview of lipid based nanocarriers developed with the aim to enhance dermal and transdermal drug delivery. A special focus is put on the nanocarrier composition, behavior and interaction mechanisms with the skin. Recent applications of lipid-based nanocarriers for the management of skin diseases and other illnesses are highlighted as well.  相似文献   
100.
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