Free-standing carboxymethyl cellulose film incorporating nanoformulated pomegranate extract for meat packaging.

This study aimed to explore an innovative approach to enhancing the shelf-life and quality of meat products through the application of an active packaging system. The study involved the development of new free-standing carboxymethyl cellulose (CMC) nanocomposite films incorporated with nanoencapsulated flavonoids derived from pomegranate extract. The loaded flavonoids, known for their antioxidant and antimicrobial properties, were nanoencapsulated via a self-assembly approach in a mixture of chitosan and sodium alginate to improve their stability, solubility, and controlled release characteristics. Chemical structure, size, and morphology of the obtained nanoparticles (Pg-NPs) were studied with FTIR, zeta-sizer, and TEM. The Pg-NPs showed particle size of 232 nm, and zeta-potential of -20.7 mV. Various free-standing nanocomposite films were then developed via incorporation of Pg-NPs into CMC-casted films. FTIR, SEM, thermal and mechanical properties, and surface wettability were intensively studied for the nanocomposite films. Barrier properties against water vapor were investigated at 2022 g·m-2d-1. The nanocomposite films possessed superior properties for inhibiting bacterial growth and extending the shelf-life of beef and poultry meat for 12 days compared with the Pg-NPs-free CMC films. This study presented a promising approach for development of active packaging systems with improved antimicrobial and antioxidant properties, and economic and environmental impacts.

Polycaprolactone composite films infused with hyperbranched polyester/reduced graphene oxide: influence on biodegradability, gas/water transport and antimicrobial properties for sustainable packaging.

Biodegradable polymers have gained great interest as ecofriendly packaging materials. However, addition of suitable fillers to the polymer matrix enhances their barrier and mechanical properties besides gaining new features such as bactericidal activity. This work deals with investigation of mechanical, gas/water transport properties and biodegradability performance of films based on polycaprolactone (PCL) reinforced by 1wt% of reduced graphene oxide (RGO) or modified graphene (mRG). To achieve this goal, nanosheets of RGO were firstly prepared then their surfaces were modified through in situ polymerization of hyperbranched polyester (PES) to obtain mRG. Then PCL was loaded with both fillers, and the nanocomposite films were prepared by a casting technique. Studying of the thermal properties of the films showed that the addition of RGO or mRG had no influence on the crystallinity of the PCL matrix. Although the mechanical characteristics of the PCL did not change when either filler was added, there was an increase in permeability and diffusivity in the presence of the fillers regardless of their composition. Nevertheless, the nanocomposites demonstrated antimicrobial properties against S. aureus and E. coli as models for Gram-positive and Gram-negative bacteria, respectively. The biodegradability test performed on the prepared film PCL, and those containing 1% of the filler, PCL/RGO, and PCL/mRG, emphasized that the film degradation became pronounced after three months for all samples.

Photoluminescent and photochromic smart window from recycled polyester reinforced with cellulose nanocrystals.

Smart windows with long-persistent phosphorescence, ultraviolet (UV) light protection, high transparency, and high rigidity were developed by easily immobilizing varying ratios of lanthanide-activated aluminate phosphor nanoscale particles within a composite of recycled polyester/cellulose nanocrystals (RPET/CNC). Cellulose nanocrystals were prepared from rice straw waste. Cellulose nanocrystals were used at low concentration as both crosslinker and drier to improve both transparency and hardness. The phosphor nanoscale particles must be distributed into the recycled polyester/cellulose nanocrystals composite bulk without agglomeration to produce transparent RPET/CNC substrates. Photoluminescence characteristics were also studied using spectroscopic profiles of excitation/emission and decay/lifetime. The hardness efficiency was also examined. This transparent recycled polyester waste/cellulose nanocrystals nanocomposite smart window has been shown to change colour under UV light to strong green and to greenish-yellow when it is dark, as proved by Commission Internationale de l'éclairage (CIE) laboratory colour parameters. It was found that the afterglow RPET/CNC smart window had phosphorescence intensities of 428, 493, and 523 nm upon excitation at 368 nm. There was evidence of improved UV shielding, photostability, and hydrophobic activity. In the presence of a low phosphor ratio, the luminescent RPET/CNC substrates showed quick and reversible fluorescence photochromic activity when exposed to UV radiation.

Magnetic resonance imaging of severe idiopathic club foot treated with one-week accelerated Ponseti (OWAP) technique.

PURPOSE: This study aims to evaluate changes in tarsal bones relationship after the use of one week accelerated Ponseti method in the treatment of severe idiopathic clubfoot using MRI. We hypothesize that one-week accelerated Ponseti is at least as effective as standard techniques in achieving the desirable MRI parameters. METHODS: This is a prospective study of 8 children with severe idiopathic clubfeet (Pirani 6) (4 unilateral and 4 bilateral) treated before the age of three months with one-week accelerated Ponseti technique, as described in a former study with minimum 2-year follow-up. The 8 corrected feet were compared with the 4 unilateral normal feet at clinical and radiological levels using a Pirani scoring system and an MRI, respectively. RESULTS: Clinical results showed that Pirani score was 1.1 in the last follow up in comparison to Pirani 6 pretreatment (p < 0.05). MRI results indicated that the malleocalcaneal angle, axial malleocalcaneal index, coronal tibiocalcaneal angle, sagittal talocalcaneal angle, and talar head neck calcaneal rotation showed statistical difference between the two groups (p < 0.05). Sagittal malleocalcaneal index, sagittal tibiocalcaneal angle, talar head neck rotation related to talar body, and posterior calcaneal rotation showed no statistical difference between normal feet and clubfeet after correction (p value >0.05). CONCLUSION: One-week accelerated Ponseti technique showed to be as effective and safe as other treatment methods through clinical and MRI follow up data. MRI role was to confirm the efficiency of this innovative accelerated technique, but not used as a routine follow up.

User-friendly lab-on-paper optical sensor for the rapid detection of bacterial spoilage in packaged meat products.

A lab-on-paper colorimetric sensor for detection and quantification of bacterial meat spoilage is reported. Bromocresol purple (BCP) and bromothymol blue (BTB) were used for the construction of the proposed sensor. An Android application allowing fast detection and accurate quantification of bacteria in the spoiled chicken meat samples was developed. The sensor was applied to the determination of spoilage in real chicken-meat samples, at chiller and room temperatures, and can be used for producing smart meat-packaging films. Linearity ranges were found to be 11.2 × 103 to 1.12 × 106 and 38.0 × 103 to 1.12 × 106 CFU g-1 for BTB and BCP, respectively. The calibration plots showed correlation coefficients (r) of 0.9998 (slope: 2.48 g CFU-1) and 0.9999 (slope: 1.95 g CFU-1) in case of bromothymol blue and bromocresol purple, respectively. The Android application uses standard images to plot a calibration curve for calculating the microbial count in the samples and relates it to the standard limits. Thereafter, the application shows a message with the product's freshness degree ranging from excellent to poor.

Prevalence of Hypothyroidism among Dialysis Patients in Palestine: A Cross-Sectional Study.

INTRODUCTION: The kidney affects the thyroid gland causing various derangements in its function whenever the kidney is impaired, even with a minor imperfection in its job, and this makes dialysis patients more prone to thyroid disorders with subsequent increase in mortality and morbidity. This study aims to assess the prevalence of thyroid disease (hypo- and hyperthyroidism) among dialysis patients and their associated factors. METHODS: This cross-sectional study was conducted in the dialysis unit of An-Najah National University Hospital. 209 dialysis patients (60% were male, 57.6 ± 14.5 years, mean age) meeting our inclusion criteria were tested for thyrotropin (TSH) and free thyroxine (FT4) in addition to routine laboratory tests. Findings. The prevalence of hypothyroidism was assessed as 16.3% (95% CI = 11.29% to 21.3%), overt hypothyroidism was 9.1%, and subclinical hypothyroidism was 7.2%. Subclinical hyperthyroidism prevalence was 1%, and no overt hyperthyroidism cases were reported. We observed no significant association between thyroid state and age, gender, duration of dialysis, or weight. Discussion. Hypothyroidism (both subclinical and overt type) is commonly seen in dialysis patients, and its symptoms are ordinary complains even in euthyroid dialysis patients, and this warrants screening programs and more studies on the efficacy of thyroid hormone supplements.

Synergistic effect of zinc oxide nanorods on the photocatalytic performance and the biological activity of graphene nano sheets.

In this work, decoration of the graphene surface with 5 wt. % ZnO nanorods (ZnO NRs), to ensure the potential photocatalytic performance of the formed nanocomposites, is demonstrated. Graphene oxide (GO) was synthesized with Hummer method followed by reduction to give reduced graphene oxide (RGO). The adjustable nano-compositing exhibited long-sought workability not only in in-situ incorporation of nanorods while reduction of graphene oxide (IZG) but also in ex-situ mixing of RGO or GO with the nanorods, (EZG) and (ZGO) respectively. The demineralization of synthetic wastewater has been evaluated by chemical oxygen demand and the obtained nanocomposites possess enhanced photocatalytic activities with 30 % and 35% over pure RGO and GO, respectively. This higher efficiency could be attributed to the synergistic effect between ZnO and the planner structure of graphene sheets which developed unprecedented polycrystalline structure. Also, the results proved that even the RGO or GO have played a dual function in photocatalysis, adsorption, and degradation. Also, the bactericidal effect of the prepared samples was studied against deleterious microorganisms. The findings of this work pave the way for the new generation of highly efficient photocatalysts based graphene with economic attraction and environmental impact.

Functionalized κ-carrageenan/hyperbranched poly(amidoamine)for protease immobilization: Thermodynamics and stability studies.

Hyperbranched polyamidoamine (PAMAM) has a high density of surface amino groups. This feature was exploited in the surface modification of κ-carrageenan gel beads for successful protease immobilization. The optimum PAMAM pH was at 2.1 and 9.3. However, treatment of κ-carrageenan gel beads at the higher pH showed re-usability for more than seven successive times. As a result of central composite design optimization, the maximum immobilization yield was obtained by soaking 8 U for 24 h. The comparative thermodynamics studies showed an enhancement in the thermal stability at high temperature for the immobilized protease as well as increased half-life time from 24.06 min to 79.95 min. Also, the D-values increased from 165.03 min to 548.23 min for free and immobilized enzyme, respectively. Moreover, the enzyme stability enhancement for the immobilized protease catalyst was accompanied with a remarkable increase in the enthalpy and in the free energy. Immobilized protease onto Carr-PAMAM gel beads can retain 89% of its initial activity and lost only 11% after 8 weeks of storage at 4 °C. Furthermore, an effective removal of silver from used X-ray film by the immobilized protease was achieved for six repeated cycles.

Antifouling and antimicrobial polyethersulfone/hyperbranched polyester-amide/Ag composite.

This study provided a facile approach for the development of antifouling and antibacterial polyethersulfone (PES) composite film. Mainly, hyperbranched polyester-amide (PESAM) was used as both the reducing and capping agent for the in situ formation of AgNPs. The nanoparticles were intensively investigated using Fourier transform infrared spectroscopy (FTIR), ultra-violet spectroscopy (UV-vis), scanning and transmission electron microscopy (SEM & TEM) and X-ray diffraction (XRD). AgNPs were narrowly distributed with an average particle size of about 6 nm. PESAM was mixed with PES to realize free-standing film using the phase inversion method. The inclusion of PESAM in the composite film significantly improved hydrophilicity as confirmed by the contact angle measurements. Furthermore, SEM and EDX investigations confirmed that PESAM induced the in situ formation of AgNPs not only on the film surface but also inside its macro-voids. The composite film (PES/PESAM/Ag) displayed significant antibacterial potential against Gram positive and Gram negative bacteria. Overall, the described method paves the way towards development of advanced PES composite films with antimicrobial properties for broad application areas that include desalination membranes or active packaging materials.

Green synthesis of cellulose nanofibers using immobilized cellulase.

Isolation of cellulose nanofibers (CNF) using cellulase immobilized on cheap and easily formed polymeric gel disks is discussed. Such gel disks based on carrageenan gel coated with hyperbranched polyamidoamine that can covalently bind to cellulase through glutaraldehyde spacer. Thermal and mechanical stability of the coated gel disks were significantly improved. Free and immobilized cellulase exhibited maximum activities at 50 °C and pH 5. However, immobilized cellulase exhibited broader temperature stability than in the free form. Additionally, immobilized cellulase gel disks can be easily separated and reused with great reusability capacity of about 85% of the initial activity after six cycles. Immobilized cellulase was capable to disintegrate cellulose fibers providing nanofibers with diameter of 15-35 nm and several micrometers long. Overall, enhanced thermal stability and reusability of immobilized cellulase pave the way for its use in industrial production of CNF that can be applicable for biomedical and food packaging applications.

Assisted Tip Sonication Approach for Graphene Synthesis in Aqueous Dispersion.

Graphene (G) is a newcomer material that holds promising properties for many applications. The production of high quality G with a good yield is a long-standing goal for many researchers. This work emphasizes synthesis of dispersed graphene nanoplatelets (DGP) through aqueous dispersion technique in surfactant/water solution with the aid of tip sonication. A chemical method was also used to prepare graphene oxide (GO) and reduced graphene oxide (RGO) for comparison. Elemental analysis revealed the C:O ratio to be 12:1 for DGP but much lower for other graphene structures. Optical characterization of DGP, GO and RGO with UV and Raman spectroscopy confirmed the ideal structure of DGP. Moreover, X-ray diffraction (XRD) revealed the amorphous structure of DGP. Transmission electron microscope (TEM) imaging showed that DGP was composed of a few flat layers, unlike the wrinkled and partially bent multilayered G. Topological study of the DGP surface with scanning electron microscope (SEM) depicted its rough surface with (ra) value of 35 nm, as revealed using an atomic force microscope (AFM). Electrochemical measurements confirmed the higher conductivity of DGP over graphene prepared by chemical method due to lack of structural defects. Its perfect structure facilitates the mobility of charge carriers that makes it preferable in optoelectronic applications.

The usefulness of MR defecography in the evaluation of pelvic floor dysfunction: our experience using 3T MRI.

PURPOSE: To assess the usefulness of MR defecography in evaluating pelvic floor dysfunction, and to correlate several pelvic organ abnormalities with each other and with patients' symptoms and characteristics. METHODS: MR defecographic examinations performed in 3T MRI machine of 95 patients (70 females, 25 males; mean age 48) were retrospectively reviewed. Pelvic organ abnormalities from all three compartments were recorded, including the anorectal junction descent, anterior rectocele, and cystocele. These were graded according to the known HMO system in relation to the pubococcygeal line. The correlation between these different abnormalities and their relation to patient symptoms and characteristics were evaluated. RESULTS: Anorectal junction descent and anterior rectocele were most commonly observed, predominantly manifesting in female patients. Both were associated with abnormalities from all compartments. The middle compartment was the least affected, and its abnormality of uterine/vaginal descent tended to occur in association with the anterior compartment abnormality (cystocele). Anismus was low in incidence, and was not associated with other compartments abnormalities. Both enterocele/peritoneocele and intussusception were uncommon. CONCLUSION: MR defecography is the modality of choice in assessing pelvic floor dysfunction, because it can neatly show various pelvic organ abnormalities from all compartments in a dynamic fashion, which are frequently coexistent. It can even show clinically silent or unsuspected abnormalities which can impact the management of patients.