[Mediating effect of self-efficacy on self-management ability and self-management behavior in patients with type 2 diabetes mellitus].

OBJECTIVE: To investigate the mechanism of self-efficacy between self-management ability and self-management behavior and its differences among patients with different disease courses through mediation tests. METHODS: In the study, 489 patients with type 2 diabetes who attended the endocrinology departments of four hospitals in Shanxi Province and Inner Mongolia Autonomous Region from July to September 2022 were enrolled as the study population. They were investigated by General Information Questionnaire, Diabetes Self-Management Scale, Chinese version of Diabetes Empowerment Simplified Scale, and Diabetes Self-Efficacy Scale. Mediation analyses were performed using the linear regression model, Sobel test, and Bootstrap test in the software Stata version 15.0 and divided the patients into different disease course groups for subgroup analysis according to whether the disease course was > 5 years. RESULTS: In this study, the score of self-management behavior in the patients with type 2 diabetes was 6.16±1.41, the score of self-management ability was 3.99±0.74, and the score of self-efficacy was 7.05±1.90. The results of the study showed that self-efficacy was positively correlated with self-management ability (r=0.33) as well as self-management behavior (r=0.47) in the patients with type 2 diabetes (P < 0.01). The mediating effect of self-efficacy accounted for 38.28% of the total effect of self-management ability on self-management behaviors and was higher in the behaviors of blood glucose monitoring (43.45%) and diet control (52.63%). The mediating effect of self-efficacy accounted for approximately 40.99% of the total effect for the patients with disease course ≤ 5 years, while for the patients with disease course > 5 years, the mediating effect accounted for 39.20% of the total effect. CONCLUSION: Self-efficacy enhanced the effect of self-management ability on the behavior of the patients with type 2 diabetes, and this positive effect was more significant for the patients with shorter disease course. Targeted health education should be carried out to enhance patients' self-efficacy and self-management ability according to their disease characteristics, to stimulate their inner action, to promote the development of their self-management behaviors, and to form a more stable and long-term mechanism for disease management.

Fabrication of polylactic acid/paclitaxel nano fibers by electrospinning for cancer therapeutics.

Polylactic acid (PLA) is a thermoplastic and biodegradable polyester, largely derived from renewable resources such as corn starch, cassava starch and sugarcane. However, PLA is only soluble in a narrow range of solvents such as tetrahydrofuran, dioxane, chlorinated solvents and heated benzene. The limited choices of solvent for PLA dissolution have imposed significant challenges in the development of specifically engineered PLA nanofibers with electrospinning techniques. Generally, the electrospun polymeric materials have been rendered with unique properties such as high porosity and complex geometry while maintaining its biodegradability and biocompatibility for emerging biomedical applications. In this study, a new anticancer drug delivery system composed of PLA nanofibers with encapsulated paclitaxel was developed by the electrospinning of the respective nanofibers on top of a spin-coated thin film with the same chemical compositions. Our unique approach is meant for promoting strong bonding between PLA-based nanofibers and their respective films in order to improve the prolonged release properties and composite film stability within a fluctuative physiochemical environment during cell culture. PLA/paclitaxel nanofiber supported on respective polymeric films were probed by scanning electronic microscope, Fourier transform infrared spectrometer and water contact measurement for determining their surface morphologies, fibers' diameters, molecular vibrational modes, and wettability, respectively. Moreover, PLA/paclitaxel nanofibers supported on respective spin-coated films at different loadings of paclitaxel were evaluated for their abilities in killing human colorectal carcinoma cells (HCT-116). More importantly, MTT assays showed that regardless of the concentrations of paclitaxel, the growth of HCT-116 was effectively inhibited by the prolonged release of paclitaxel from PLA/paclitaxel nanofibers. An effective prolonged delivery system of paclitaxel based on PLA nanofiber-based film has demonstrated exciting potentials for emerging applications as implantable drug delivery patch in post-surgical cancer eradication.

Characterization of changes in the proteome in different regions of 3D multicell tumor spheroids.

Three dimensional multicell tumor spheroids (MCTS) provide an experimental model where the influence of microenvironmental conditions on protein expression can be determined. Sequential trypsin digestion of HT29 colon carcinoma MCTS enabled segregation into four populations comprising proliferating cells from the surface (SL), an intermediate region (IR), nonproliferating hypoxic cells from the perinecrotic region (PN), and a necrotic core (NC). Total protein was extracted from each population and subjected to iTRAQ-based quantitative proteomics analysis. From a total of 887 proteins identified, 209 were observed to be up-regulated and 114 were down-regulated in the PN and NC regions relative to the SL. Among the up-regulated proteins, components of glycolysis, TCA cycle, lipid metabolism, and steroid biosynthesis increased progressively toward the PN and NC regions. Western blotting, immunohistochemistry, and enzyme assays confirmed that significant changes in the expression of proteins involved in cellular metabolism occur in the nonproliferating fraction of cells within the viable rim. The presence of full length, functional proteins within the NC was unexpected, and further analysis demonstrated that this region contains cells that are undergoing autophagy. This study has identified possible targets that may be suitable for therapeutic intervention, and further studies to validate these are required.

Changes in physicochemical properties of egg white and yolk proteins from duck shell eggs due to hydrostatic pressure treatment.

The shell of the duck egg did not crack after pressure treatments (300 to 500 MPa; 25 degrees C; 10 min) in this study; therefore, the changes of physicochemical properties of egg white and yolk proteins from the intact shell egg by pressure treatment were first investigated and compared with those of pressurized hen liquid eggs. Although the proximate compositions of duck eggs and hen eggs were similar, the moisture and protein contents of hen whole eggs were higher than those of duck whole eggs. The protein contents of duck egg white and yolk were slightly lower than those of hen eggs, and the moisture content of duck egg white was equal to that of hen egg white, whereas that of duck egg yolk was lower than that of hen egg yolk. After pressure treatment at 500 MPa, the results of solubility, sulfhydryl content, surface hydrophobicity, and residual denaturation enthalpy showed that egg white proteins underwent slight but significant unfolding and aggregation, whereas pressure treatments below 500 MPa induced insignificant changes in the physicochemical properties. On the other hand, pressure treatments at 400 and 500 MPa significantly reduced the solubility and residual denaturation enthalpy of egg yolk proteins. However, the native PAGE result showed that pressure treatment up to 500 MPa did not affect the protein components of egg white and yolk. The results showed that the application of pressure treatment on duck shell egg may induce reversible denaturation of both egg white and yolk proteins. The egg white and yolk proteins may be prevented from denaturation after pressure treatment in the presence of the eggshell compared with the absence of the eggshell. As reported in the literature, pressure treatments at 300 to 500 MPa and 25 degrees C would be efficient for decontamination of duck shell eggs. Therefore, based on the consideration for food safety and functional properties, pressure processing can be a good preservation technique for duck shell eggs.

Effects of lead and noise exposures on hearing ability.

Lead and noise, via different mechanisms, may damage hearing ability, and, in some cases, cause severe and irreversible damage. To explore possible independent and synergistic effects of lead and noise on auditory function, the authors conducted a cross-sectional study in two lead-battery manufacturing factories. Lead and noise were the two most common sources of occupational exposures in the factories. Blood lead level, ambient lead concentration, noise exposure level, and hearing thresholds of 339 lead-battery workers-including clerical and managerial staffs-were measured. The authors obtained demographics and working histories via an interview-based structured questionnaire. A total of 220 lead-battery workers were exposed to high levels of lead and noise; their average blood lead concentration was 56.9 microg/dl, and their average noise exposure level was 86.0 dBALeq. Multivariate analysis, in which possible risk factors of hearing ability were considered, demonstrated a significant correlation between a high, long-term lead exposure index (defined by duration of employment and ambient lead concentration) and decreased hearing ability. In contrast, such a correlation between short-term lead exposure (defined by blood lead level) and hearing ability was not significant. Furthermore, neither noise exposure level alone nor the interaction between noise exposure level and short- or long-term lead exposure was correlated significantly with hearing ability. The present study raises an important, but typically ignored, issue: lead exposure might precipitate a more severe auditory than noise-exposure effect. The preservation of workers' hearing ability requires that preventive measures be taken against noise exposure, which is as essential as measures taken against lead exposure.

A study of the relationship between ambient lead and blood lead among lead battery workers.

OBJECTIVE: To examine the relationship between ambient lead levels and blood lead levels and to explore the modifiers of the relationship between ambient lead and blood lead. METHOD: A cross-sectional study was conducted in two lead battery factories. Blood lead level and ambient lead concentration were measured for each participant concurrently. A structured questionnaire was administered to collect sociodemographic characteristics and occupational history. DESIGN: Biological and personal environmental measurements of 219 lead-exposed workers were analyzed by both simple and multiple linear regression. A regression model was selected for interpretation. RESULTS: A high correlation (r = 0.62) between ambient lead (PbA) and blood lead (PbB) was observed. In addition, numerous factors, including age, sex, alcohol consumption, personal hygiene practice and type of lead exposure, were also found to influence blood lead levels. Although PbB was highly correlated with PbA, blood lead level may not be effectively lowered by reducing ambient lead level. Based on the regression coefficients, improvement of hygienic practice was more effective at lowering PbB than reducing ambient lead level. Good hygienic practice may be the preferential way to reduce lead exposure in current conditions. CONCLUSION: Education of correct work practice may be more important than engineering control in the developing countries to lower blood lead levels in lead battery factories.