不同工艺各类棉酚的反相薄层色谱分析

目的：考察苯胺法与酸法工艺制备的各类棉酚的质量,本胺法工艺制品中是否残留本胺棉酚。方法：采用RP18F反相薄层板,以丙酮-水（4：1）为展开系统分离展开。结果：苯胺法工艺生产的棉酚中出现苯胺棉酚的斑点。结论：首次用反相薄层色谱法确证了苯胺法工艺生产的棉酚中残留有苯胶棉酚。     

Delivering a psychosocial program for older people living in retirement homes during the Covid-19 pandemic: A process evaluation and recommendations for community interventions

The Covid-19 pandemic lockdown regulations caused retirement homes to temporarily ban in-person visitation potentially increasing the mental health risks of older people. An opportunity arose for a multistakeholder community collaboration to design a mental health program for older people. To evaluate the process of delivering a 12-week psychosocial program aimed at preventing loneliness, countering boredom, and providing older people in restricted settings with education about Covid-19 during the lockdown, in Durban, South Africa. A qualitative retrospective design was used. Data from two focus groups and six semistructured individual interviews conducted with stakeholders (volunteers, social workers, and residents) postproject were analyzed using reflexive thematic analysis. Stakeholders had varied experiences of the project, in terms of content, processes of engagement, and implementation, resulting in five themes. The study concluded with recommendations. A strong need exists for multistakeholder community collaborations when implementing a program where the context restricts physical access.     

统计过程控制在医用电子直线加速器机械性能监测中的应用

目的：使用统计过程控制方法分析医用电子直线加速器长期过程表现,监测加速器状态变化趋势,并评估加速器各项指标性能状态。方法：收集2019年6月至2021年4月加速器机器性能检测(MPC)数据。绘制每个机械指标的单值控制图,分析各指标过程特征,并使用过程能力指数C_pk及C_p评估加速器各项机械指标的过程质量。结果：加速器机械精度明显优于当前厂商推荐的规格限值,但控制图监测结果显示各指标均存在一定程度的过程漂移。过程能力分析结果显示所有指标的C_pk及C_p均大于1.33,过程质量优秀。结论：加速器在满足当前MPC规格限的情况下依然可能发生过程失控。统计过程控制方法可及时发现过程中的异常改变,过程能力指数可有效评估过程质量,为质量管理及临床决策提供有效的信息。     

Dependence of the Molecular Mobility and Protein Stability of Freeze-Dried γ-Globulin Formulations on the Molecular Weight of Dextran

Purpose. The effect of the molecular weight of dextran on the molecular mobility and protein stability of freeze-dried serum -globulin (BGG) formulations was studied. The stabilizing effect of higher molecular weight dextran is discussed in relation to the molecular mobility of the formulations. Methods. The molecular mobility of freeze-dried BGG formulations containing dextrans of various molecular weights was determined based on the free induction decay of dextran and water protons measured by proton NMR. The protein stability of the formulations was determined at temperatures ranging from 20 to 70°C by size exclusion chromatography. Results. Changes in the molecular mobility of freeze-dried formulations that occurred at temperatures below the glass transition temperature could be detected as the molecular mobility-changing temperature (T_mc), at which dextran protons started to exhibit a Lorentzian relaxation decay due to higher mobility in addition to a Gaussian relaxation decay. T_mc increased as the molecular weight of dextran increased. The proportion of dextran protons which exhibited the higher mobility relaxation process (P_hm) at temperatures above T_mc decreased as the molecular weight of dextran increased. Protein stability was closely related to molecular mobility. The temperature dependence of the denaturation rate changed at around T_mc, and denaturation in the microscopically liquidized state decreased as P_hm decreased with increasing molecular weight of dextran. Conclusions. The effect of the molecular weight of dextran on the protein stability of freeze-dried BGG formulations could be explained in terms of the parameters obtained by ¹H-NMR such as T_mc and P_hm. These parameters appear to be useful in preformulation and stability prediction of freeze-dried formulations.     

Measurement of Glass Transition Temperatures of Freeze-Concentrated Solutes by Differential Scanning Calorimetry

Thermal analysis of aqueous solutions in which the solute does not crystallize immediately upon freezing was carried out to define the effects of experimental parameters on thermograms in the glass transition region. The intensity of enthalpy relaxations in the glass transition region is related to both the rate of cooling and the rate of heating through the glass transition region—slow cooling or slow heating increases the extent of structural relaxation in the glassy state and increases the intensity of the endotherm. Plots of the logarithm of heating rate versus l /Tg are linear, and activation enthalpies for structural relaxation are in the range of 210–350 kJ/mol. For polymeric solutes, both the activation enthalpies for structural relaxation and the heat capacity change accompanying the glass transition increase with increasing molecular weight of the solute. Molecular weight dependence of the observed midpoint of the glass transition agrees with the Fox–Flory relationship. Results are compared and contrasted with glass transitions in solid polymers and with the glass transition of hyperquenched water. Practical implications for characterization of formulations intended for freeze-drying are discussed.     

Physical Stability and Protein Stability of Freeze-Dried Cakes During Storage at Elevated Temperatures

The relationship between physical stability of freeze-dried cakes and protein stability during storage was studied using -galactosidase as a model protein and inositol as an excipient. Amorphous samples freeze-dried from solutions containing the enzyme and various concentrations of inositol in sodium phosphate buffer (50 mM, pH 7.4) were stored for 7 days over P₂O₅ at 40 to 70°C. Structural collapse and inositol crystallization were observed in some of the samples, depending on the formulation and storage temperature. The physical stability of freeze-dried samples was also studied by differential scanning calorimeter (DSC). Inositol showed a protein-stabilizing effect when its amorphous form was retained during storage, regardless of structural collapse. However, crystallization of inositol during storage removed its stabilizing effect. Addition of water-soluble polymers such as dextran, Ficoll and carboxymethyl cellulose sodium salt (CMC-Na) preserved activity of the enzyme by preventing inositol crystallization.     

Patient,Provider, and Treatment Factors Associated with Poor-Quality Care for Schizophrenia

Interventions are needed to improve the quality of care for schizophrenia. However, in designing these interventions it would be helpful to understand better which patients are at highest risk for poor-quality care and why care for this disorder is often of poor quality. We study the extent to which patient and treatment factors are associated with poor-quality care in 224 patients randomly sampled from two mental health clinics. Quality of medication management is evaluated using an established method based on national treatment recommendations. Multivariate regression is used to study the effect of patient and treatment factors on treatment quality, controlling for provider. Risk for poor-quality care was greater for patients who were more severely ill, older, and less compliant with treatment recommendations. There were trends toward poor management of symptoms in men and substance abusers, and poor management of side effects in Black patients. Provision of poor-quality care was associated with failure to document symptoms and side effects in the medical record. Interventions to improve care for schizophrenia should attend to the need for accurate clinical assessment and strategies for managing challenging clinical situations.