Durable Surface Modification of Low-Density Polyethylene/Nano-Silica Composite Films with Bacterial Antifouling and Liquid-Repelling Properties for Food Hygiene and Safety.

The growing prevalence of antimicrobial resistance in bacterial strains has increased the demand for preventing biological deterioration on the surfaces of films used in applications involving food contact materials (FCMs). Herein, we prepared superhydrophobic film surfaces using a casting process that involved the combination of low-density polyethylene (LDPE) with solutions containing surface energy-reducing silica (SRS). The bacterial antifouling properties of the modified film surfaces were evaluated using Escherichia coli O157:H7 and Staphylococcus epidermidis via the dip-inoculation technique. The reduction in bacterial populations on the LDPE film embedded with SRS was confirmed to be more than 2 log-units, which equates to over 99%, when compared to the bare LDPE film. Additionally, the modified film demonstrated liquid-repelling properties against food-related contaminants, such as blood, beverages, and sauces. Moreover, the modified film demonstrated enhanced durability and robustness compared to one of the prevalent industry methods, dip-coating. We anticipate that the developed LDPE/nano-silica composite film represents a promising advancement in the multidisciplinary aspects of food hygiene and safety within the food industry, particularly concerning FCMs.

Nickel affects gill and muscle development in oriental fire-bellied toad (Bombina orientalis) embryos.

The developmental toxicity of nickel was examined in the embryos of Bombina orientalis, a common amphibian in Korea. Based on a standard frog embryo teratogenesis assay, the LC50 and EC50 for malformation of nickel after 168h of treatment were 33.8µM and 5.4µM, respectively. At a lethal concentration (100µM), nickel treatment decreased the space between gill filaments and caused epithelial swelling and abnormal fusion of gill filaments. These findings suggest that nickel affects the functional development of gills, leading to embryonic death. At sublethal concentrations (1-10µM), nickel produced multiple embryonic abnormalities, including bent tail and tail dysplasia. At 10µM, nickel significantly decreased tail length and tail muscle fiber density in tadpoles, indicating inhibition of myogenic differentiation. Before hatching, the pre-muscular response to muscular response stages (stages 26-31) were the most sensitive period to nickel with respect to tail muscle development. During these stages, MyoD mRNA was upregulated, whereas myogenic regulatory factor 4 mRNA was downregulated by 0.1µM nickel. Calcium-dependent kinase activities in muscular response stage embryos were significantly decreased by nickel, whereas these activities were restored by exogenous calcium. In tadpoles, 10µM nickel significantly decreased the expression of the myosin heavy chain and the 12/101 muscle marker protein in the tail. Expression was restored by exogenous calcium. Our results indicate that nickel affects muscle development by disrupting calcium-dependent myogenesis in developing B. orientalis embryos.

Developmental and acute toxicity of cetylpyridinium chloride in Bombina orientalis (Amphibia: Anura).

In an effort to evaluate the toxicity of cetylpyridinium chloride (CPC), a cationic surfactant in amphibians, we examined the developmental and acute toxicity of CPC in Bombina orientalis embryos and tadpoles. Embryonic exposure to 2.0µM (0.72mg/l) CPC for 7 days significantly decreased the survival rates and increased DNA damage in the intestine of developed tadpoles. Exposure to 1.5µM (0.54mg/l) CPC significantly decreased the growth of embryos and increased developmental abnormalities. The 168-h LC50 and EC50 values of CPC were 1.95µM (0.697mg/l) and 1.48µM (0.531mg/l) in embryos, respectively. In an extended acute toxicity test using tadpoles, the 168-h LC50 value of CPC was 5.07µM (1.82mg/l). In terms of survival and growth rates, the lowest observed effective concentration of CPC was 1.5µM. At sub-lethal concentrations (1.0 and 2.0µM) CPC treatment to embryos increased lipid peroxidation in the intestine and gills of developed tadpoles, indicating that CPC can impose oxidative stress. At 2.0µM CPC, pro-apoptotic Bax and Bak mRNA levels were significantly increased together with DNA fragmentation, indicative of apoptotic cell death. CPC in freshwater system may threaten the normal development of amphibian embryos.

External control of exhalation for cough assistance: a method for patients with glottis dysfunction and/or tracheostomy.

OBJECTIVE: To investigate the effectiveness of our method of assisting a cough by mimicking the functions of the glottis in patients with bulbar muscle weakness or paralysis and/or those who had a tracheostomy tube. DESIGN: Before-after trial. SETTING: University rehabilitation hospital. PARTICIPANTS: Patients (N=35) with bulbar muscle weakness or paralysis and/or those who had a tracheostomy tube. INTERVENTIONS: Not applicable. MAIN OUTCOME MEASURES: The unassisted peak cough flow (PCF), the assisted PCF, and the assisted PCF with the external control method mimicking glottis function by an end-inspiratory external closure of the airways. RESULTS: Of the 35 patients, 13 were tracheostomized cervical cord injury patients, 11 were neuromuscular disease (NMD) patients with glottis dysfunction only, and 11 were NMD patients with a tracheostomy and glottis dysfunction. Assisted PCF with the external control method were higher than unassisted PCF and/or assisted PCF in all patients. Assisted PCF with the external control methods were measured in all of the patients even when the unassisted PCFs and/or assisted PCFs could not be measured. For patients with measurable assisted PCFs, the assisted PCF with the external control methods were significantly higher than the assisted PCFs. CONCLUSIONS: We showed the effectiveness of our method of assisting a cough by external control of the glottis in patients with bulbar muscle weakness or paralysis and/or those who had a tracheostomy tube who cannot effectively cough with the help of existing cough assistance methods.

Personalized healthcare comment service for hypertension patients using mobile device.

Hypotension and hypertension are chronic diseases, which can be effectively prevented and controlled by constantly monitoring. In this study, personalized healthcare comment service for hypertension patients is proposed and implemented. We have developed algorithms of health state code generation and doctor's comments for patients on case-by-case basis. This prototype service shows how such personalized comments can manage patients with hypertension using blood pressure monitor and mobile device.