Rational design of chitosan/guar gum/zinc oxide bionanocomposites based on Roselle calyx extract for Ras cheese coating.

Roselle calyx extract (RE) was used to prepare zinc oxide nanoparticles (ZnO-NPs) as a green technique. In the current work, chitosan/guar gum/zinc oxide bionanocomposites based on Roselle calyx extract, namely (CS/GG/RE-ZnO) bionanocomposite were prepared. The synthetic ZnO-NPs and the prepared bionanocomposites were characterized by Fourier transforms infrared spectroscopy (FT-IR), transmission electron microscopy (TEM), X-ray diffraction (XRD), and scanning electron microscopy (SEM). Moreover, the addition of RE-ZnO nanocomposites was improved mechanical, permeability, antimicrobial and antioxidant properties of bionanocomposite films. The influence of coating Ras cheese with the fabricated CS/GG/RE-ZnO bionanocomposites on chemical, microbiological, and sensorial properties of Ras cheese was evaluated during ripening in comparing with uncoated cheese. Ras cheese coating with bionanocomposite film containing 3% RE-ZnO nanocomposites protects their surface for around three months from yeasts, molds and other bacteria growth. The prepared CS/GG/RE-ZnO bionanocomposite films can be used as a promising candidate for food packaging applications.

Development of bionanocomposite materials and its use in coating of Ras cheese.

The aim of the present study was to prepare and characterize bionanocomposite materials, and to evaluate its use in the coating of Ras cheese. The bionanocomposite materials were made from mixture of chitosan/polyvinyl alcohol with loading of titanium dioxide nanoparticles (TiO2-NPs) from (0.5-2%). The prepared nanoparticles as well as the bionanocomposites were evaluated using, XRD, SEM, TEM, FT-IR and final contact angle. Furthermore, the mechanical properties and water vapor transmission rate (WVTR) of the fabricated bionanocomposites were evaluated. The impacts of coating Ras cheese with the prepared bionanocomposite on weight losses and microbiological, chemical, and physical characteristics of the Ras cheese were assessed during ripening in comparison to the uncoated cheese. Coating of cheese decreased the weight and moisture losses but didn't affect the normal ripening changes in the microbiological, chemical and textural properties of Ras cheese. Coating cheese with film containing 2% TiO2-NPs eliminated mold growth on the cheese surface.

Visante optical coherence tomography and tear function test evaluation of cholinergic treatment response in patients with sjögren syndrome.

PURPOSE: To evaluate tear meniscus changes in patients with Sjögren syndrome (SS) receiving oral pilocarpine with Visante optical coherence tomography (OCT). METHODS: Eight patients with primary SS were recruited in this prospective interventional case series study. Patients received pilocarpine tablets twice a day for 3 months. Visual analog scale assessment for dry eye and dry mouth symptoms was carried out. Patients underwent OCT and slit-lamp microscopy graticule scale tear meniscus height (TMH) measurements, strip meniscometry testing, tear film breakup time measurement, fluorescein and Rose Bengal staining, and the Schirmer 1 test. The data were analyzed 1 week, 1 month, and 3 months after treatment. Mann-Whitney test was performed. RESULTS: Visual analog scale assessment showed a significant time-wise improvement (P < 0.05). OCT and graticule scale TMH measurements significantly improved after 1 week (P < 0.05), 1 month, and 3 months of treatment (P < 0.001). Strip meniscometry, mean tear film stability, and fluorescein and Rose Bengal scores remained improved 3 months after treatment (P < 0.001), whereas Schirmer 1 test values tended to improve without statistical significance. CONCLUSIONS: Visante OCT was effective in monitoring tear meniscus changes during the course of treatment noninvasively and quickly. Oral pilocarpine seemed to be effective in improving TMH, and the signs and symptoms of dryness in patients with SS.

Corneal and retinal effects of ultraviolet-B exposure in a soft contact lens mouse model.

PURPOSE: To investigate the lipid and DNA oxidative stress as well as corneal and retinal effects after ultraviolet B (UV-B) exposure in mice, with or without silicon hydrogel soft contact lenses (SCL). METHODS: Twenty-eight C57BL6-strain male mice were divided into four groups: group I, control group with no SCL (SCL [-]) and no UV-B exposure (UV-B [-]); group II, senofilcon A SCL (senofilcon [+]) with UV-B exposure (UV-B [+]); group III, lotrafilcon A SCL (lotrafilcon [+]) with UV-B exposure (UV-B [+]); and group IV, no SCL (SCL [-]), but with UV-B exposure (UV-B [+]). All mice except group I received UV-B exposure for 5 days for a total dose of 2.73 J/cm(2). All mice underwent tear hexanoyl-lysine (HEL) and tear cytokine ELISA measurements, and fluorescein and rose bengal corneal staining before and after UV-B exposure. Corneal specimens underwent immunohistochemistry staining with CD45, HEL, 4-hydroxynonenal (4-HNE), and 8-hydroxy-2'-deoxyguanosine (8-OHdG) antibodies and evaluation with electron microscopy. RESULTS: All mice without SCL but exposed to UV-B developed corneal edema, ulcers, or epithelial damage compared with mice with senofilcon A SCL and exposure to UV-B. Tear HEL and cytokine levels significantly increased in mice without SCL after UV-B exposure. Immunohistochemistry showed a significantly higher number of cells positively stained for CD45, 8-OHdG, HEL, and 4-HNE in the corneas of mice without SCLs compared with those with senofilcon A after UV-B exposure. CONCLUSION: Silicon hydrogel SCL showed corneal and retinal protective effects, owing to UV blocking properties, against oxidative stress-related membrane lipid and cellular DNA damage.

The effects of 2 week senofilcon-A silicone hydrogel contact lens daily wear on tear functions and ocular surface health status.

PURPOSE: To prospectively investigate the effects of 2 week senofilcon A contact lens (CL) daily wear on the functional visual acuity (VA), ocular surface and tear film. METHODS: Seventeen right eyes of 17 senofilcon A CL wearers without any ocular or systemic diseases were examined before and 2 weeks after lens wear. Visual acuity measurements, tear evaporation rate, ELISA for tear cytokines, strip meniscometry, tear lipid layer interferometry, tear film break-up time (BUT), in vivo confocal microscopy, corneal sensitivity, ocular surface vital staining, Schirmer I test and brush cytology for MUC5AC mRNA expression were performed before and after CL wear. RESULTS: The best corrected Landolt VA, functional VA parameters, the mean lipid layer interferometry grades, tear evaporation rates, Schirmer test values, vital staining scores and in vivo confocal microscopy parameters did not show any significant differences after 2 weeks of CL wear. The tear film BUT showed a significant decrease together with a significant down regulation of MUC5 AC mRNA expression after CL wear. A statistically significant elevation in the mean tear interleukin (IL)-6 concentration was also observed after 2 weeks of CL wear. CONCLUSIONS: Two week senofilcon A daily CL wear seems to be associated with tear instability, a decrease in MUC5AC expression, and elevation of IL-6 in tears without significant alterations in epithelial damage scores or in the morphology or density of in vivo keratoconjunctival cells and nerves. Alterations associated with long term wear and patients with dry eye disease need to be studied in future trials.

Effect of controlled adverse chamber environment exposure on tear functions in silicon hydrogel and hydrogel soft contact lens wearers.

PURPOSE: To prospectively evaluate the effect of controlled adverse chamber environment (CACE) exposure on tear function, including tear osmolarity, in subjects wearing narafilcon A versus those wearing etafilcon A soft contact lens (SCL). METHODS: Thirty-one healthy subjects with no history of contact lens wear (13 women, 18 men; average age, 30.5 ± 6.5 years) were randomly divided into age- and sex-matched groups (15 subjects wearing narafilcon A SCL; 16 subjects wearing etafilcon A SCL) and entered a CACE for 20 minutes. All subjects underwent tear osmolarity, tear evaporation rate, strip meniscometry, tear film breakup time, fluorescein vital staining, and functional visual acuity measurement before and after exposure to the controlled adverse chamber. RESULTS: The mean blink rate increased with significant deteriorations in the mean symptom VAS scores, mean tear osmolarity, tear evaporation rate, strip meniscometry score, and tear stability with CACE exposure along with a decrease in visual maintenance ratio in functional visual acuity testing in etafilcon A wearers. The mean symptom VAS scores, mean tear evaporation rate, tear stability, blink rates, and visual maintenance ratios did not change significantly in narafilcon A wearers after CACE exposure. CONCLUSIONS: This study suggested marked tear instability, higher tear osmolarity, and increased tear evaporation with marked dry eye and visual symptomatology in nonadapted hydrogel SCL wearers, suggesting that silicone hydrogel SCLs may be suitable for persons who live and work in cool, low-humidity, and windy environments, as tested in this study.