Molecular design of environmentally sensitive complexation hydrogels for oral protein delivery

Novel pH-sensitive complexation hydrogels containing pendent glucose (P(MAA-co-MEG)) or grafted PEG chains (P(MAA-g-EG)) were synthesized by photopolymerization. These hydrogels showed excellent properties for oral protein delivery carriers such as pH-responsive swelling behavior and protective ability for protein. Both classes of the hydrogels exhibited sharp transitions between the swollen and the collapsed states at pH 5. Their equilibrium swelling ratio increased at pH values above 5, but decreased at pH values below 5. The swelling behavior was controlled more by polymer relaxation (Case II) than by penetrant diffusion at pH 7.0. The effect of complexation on the molecular network structure was investigated using ATR-FTIR spectroscopy. Both P(MAA-co-MEG) and P(MAA-g-EG) networks could form hydrogen bonds at low pH (below 5) by protonation of the carboxylic acid groups of the PMAA, while electrostatic interaction prevailed at high pH (above 5) due to the ionization of the carboxylic acid groups of the PMAA. At low pH, the presence of the grafted PEG chains contributed to the formation of more hydrogen bonding. However, the presence of pendent glucose groups disrupted the hydrogen bonding between the carboxylic acid groups of the PMAA. The feasibility of these hydrogels as oral protein delivery carriers was also evaluated. The pH-responsive release behavior of insulin was observed from both P(MAA-co-MEG) and P(MAA-g-EG) hydrogels. In acidic media (pH 2.2), insulin release from the hydrogels was very slow. However, as the pH of the medium was changed to 6.5, a rapid release of insulin occurred. After treatment with a simulated gastric solution, the biological activity of insulin that was inside both classes of hydrogels was retained. In P(MAA-co-MEG) hydrogels, insulin biological activity decreased when the pendent glucose content increased. In P(MAA-g-EG) hydrogels, when the grafted PEG molecular weight increased, insulin biological activity decreased. Finally, hydrogels of P(MAA-co-MEG) prepared with an initial ratio of 1:4 MEG:MAA and P(MAA-g-EG) containing PEG chain of 200 molecular weight showed the greatest change in insulin release rate from acidic to basic pH solutions and the greatest protective effect for insulin in the simulated GI tract condition

Lab-on-a-Chip Pathogen Sensors for Food Safety

There have been a number of cases of foodborne illness among humans that are caused by pathogens such as <em>Escherichia coli </em>O157:H7, <em>Salmonella typhimurium</em>, <em>etc</em>. The current practices to detect such pathogenic agents are cell culturing, immunoassays, or polymerase chain reactions (PCRs). These methods are essentially laboratory-based methods that are not at all real-time and thus unavailable for early-monitoring of such pathogens. They are also very difficult to implement in the field. Lab-on-a-chip biosensors, however, have a strong potential to be used in the field since they can be miniaturized and automated; they are also potentially fast and very sensitive. These lab-on-a-chip biosensors can detect pathogens in farms, packaging/processing facilities, delivery/distribution systems, and at the consumer level. There are still several issues to be resolved before applying these lab-on-a-chip sensors to field applications, including the pre-treatment of a sample, proper storage of reagents, full integration into a battery-powered system, and demonstration of very high sensitivity, which are addressed in this review article. Several different types of lab-on-a-chip biosensors, including immunoassay- and PCR-based, have been developed and tested for detecting foodborne pathogens. Their assay performance, including detection limit and assay time, are also summarized. Finally, the use of optical fibers or optical waveguide is discussed as a means to improve the portability and sensitivity of lab-on-a-chip pathogen sensors

A Brief Review of Gel Polymer Electrolytes Using In Situ Polymerization for Lithium-ion Polymer Batteries

Polymer electrolytes (PEs) have been thoroughly investigated due to their advantages that can prevent severe problems of Li-ion batteries, such as electrolyte leakage, flammability, and lithium dendrite growth to enhance thermal and electrochemical stabilities. Gel polymer electrolytes (GPEs) using in situ polymerization are typically prepared by thermal or UV curing methods by initially impregnating liquid precursors inside the electrode. The in situ method can resolve insufficient interfacial problems between electrode and electrolyte compared with the ex situ method, which could led to a poor cycle performance due to high interfacial resistance. In addition to the abovementioned advantage, it can enhance the form factor of bare cells since the precursor can be injected before polymerization prior to the solidification of the desired shapes. These suggest that gel polymer electrolytes prepared by in situ polymerization are a promising material for lithium-ion batteries

A Brief Review of Gel Polymer Electrolytes Using In Situ Polymerization for Lithium-ion Polymer Batteries

Polymer electrolytes (PEs) have been thoroughly investigated due to their advantages that can prevent severe problems of Li-ion batteries, such as electrolyte leakage, flammability, and lithium dendrite growth to enhance thermal and electrochemical stabilities. Gel polymer electrolytes (GPEs) using in situ polymerization are typically prepared by thermal or UV curing methods by initially impregnating liquid precursors inside the electrode. The in situ method can resolve insufficient interfacial problems between electrode and electrolyte compared with the ex situ method, which could led to a poor cycle performance due to high interfacial resistance. In addition to the abovementioned advantage, it can enhance the form factor of bare cells since the precursor can be injected before polymerization prior to the solidification of the desired shapes. These suggest that gel polymer electrolytes prepared by in situ polymerization are a promising material for lithium-ion batteries

Significance of serum ferritin as a prognostic factor in advanced hepatobiliary cancer patients treated with Korean medicine: a retrospective cohort study

Abstract Background Advanced hepatobiliary cancers are highly lethal cancers that require precise prediction in clinical practice. Serum ferritin level increases in malignancy and high serum ferritin level is associated with poor survival in various cancers. This study aimed to identify whether serum ferritin could independently predict the overall survival (OS) of patients with advanced hepatobiliary cancers. Methods The retrospective cohort study was performed by reviewing medical records of patients with advanced hepatobiliary cancers from June 2006 to September 2016. The demographic and clinicopathological characteristics as well as the biochemical markers were evaluated at the initiation of Korean medicine (KM) treatment. The OS was calculated using Kaplan-Meier estimates. The Cox proportional hazard model was used to identify the independent prognostic significance of serum ferritin for survival. Results The median OS of all subjects was 5.1 months (range, 0.5–114.9 months). The median OS of group with low ferritin levels and that with high ferritin levels was 7.5 months (range, 0.7–114.9 months) and 2.8 months (range, 0.5–22.8 months), respectively (P < 0.001). The results of the univariate analysis showed that the Eastern Cooperative Oncology Group Performance Status (ECOG-PS) (P = 0.002), tumor type (P = 0.001), prior treatment (P = 0.023), serum ferritin (P < 0.001), hemoglobin (P = 0.002), total bilirubin (P = 0.002), gamma-glutamyl transpeptidase (P = 0.007), albumin (P = 0.013), white blood cell (P = 0.002), and C-reactive protein (CRP) (P < 0.001) were significant factors for the patients’ survival outcome. On multivariate analysis controlling confounding factors, ferritin (P = 0.041), CRP (P = 0.010), ECOG-PS (P = 0.010), and tumor type (P = 0.018) were identified as independent prognostic factors for survival. Conclusions These results indicate that serum ferritin is a valid clinical biochemical marker to predict survival of patients with advanced hepatobiliary cancers

Prognostic Value of Functional Assessment of Cancer Therapy-General (FACT-G) in Advanced Non-Small-Cell Lung Cancer Treated with Korean Medicine

Objectives. The impact of health-related quality of life (HRQoL) on survival has been investigated in patients with various cancers. Here, we evaluated the prognostic value of HRQoL using the Functional Assessment of Cancer Therapy-General (FACT-G) in advanced non-small-cell lung cancer (NSCLC) patients treated with Korean medicine. Methods. A retrospective review of medical records and FACT-G scores of patients with advanced NSCLC who received treatment with Korean medicine was conducted. The reliability of the FACT-G was determined using Cronbach’s alpha and calculating floor-and-ceiling effects. Correlations between FACT-G scores were estimated using Pearson’s correlation analysis. Overall survival was calculated using the Kaplan–Meier method, and the prognostic impact of FACT-G scores and patients’ characteristics was evaluated with Cox proportional hazards regression. Results. Of the 165 enrolled patients, 115 (70%) had extrathoracic metastasis and 139 (84%) had undergone prior anticancer treatment. The median overall survival was 10.1 months. The mean FACT-G score was 65.0, and Cronbach’s alpha for the FACT-G was 0.917. Age ≥65 years, male sex, smoking history, squamous-cell carcinoma, Eastern Cooperative Oncology Group Performance Status (ECOG-PS) ≥2, and presence of extrathoracic metastasis were associated with an increased risk of mortality. High FACT-G total scores, physical well-being (PWB), emotional well-being, and functional well-being were associated with prolonged survival. After adjusting for age, sex, smoking history, ECOG-PS, histological type, and presence of extrathoracic metastasis, a high FACT-G total score (hazard ratio (HR): 0.99, p=0.032) and high PWB score (HR: 0.94, p<0.001) were associated with prolonged survival as independent prognostic factors in patients with advanced NSCLC. Conclusion. The FACT-G total score and PWB score as HRQoL measurements were significant prognostic factors for survival in advanced NSCLC patients treated with Korean medicine. This finding implies that the FACT-G can be used in clinical practice as a predictor of survival in patients with advanced NSCLC