Effect of green tea extract on gelatin-based films incorporated with lemon essential oil.

The use of natural polymers, such as gelatin and other proteins, has increased in an attempt to replace part of the consumption of petroleum-based packaging. This study evaluated the influence of green tea extract and lemon nanoemulsion on mechanical, thermal and permeability properties of gelatin matrix. The results showed that green tea increased the gelatin tensile strength (TS) from 86 ± 7 MPa to 101 ± 5 MPa, on the other hand, the nanoemulsion decreases to 78 ± 8 MPa. The incorporation of green tea and nanoemulsion enhanced the water vapor permeability of gelatin film; this could be due to the interacting with the hydrophobic domains of gelatin. This was indicated by melting point (Tm) in differential scanning calorimetry (DSC) and degradation temperatures in the thermogravimetric analysis (TG), respectively. Changes in FTIR spectra of gelatin film were observed when the green tea and nanoemulsion were incorporated. Therefore, this study showed a new characterization and formulation of gelatin films incorporated by green tea extract and lemon nanoemulsion and their potential for edible film.

Design of Biodegradable Films Using Pecan Nut Cake Extracts for Food Packing.

The excessive consumption of plastic packaging and its consequent disposal and accumulation in the environment have aroused the interest of researchers in developing packaging that can cause less harm to nature. In this sense, this article presents research on the addition of antioxidant extracts from pecan nut cake in biodegradable packaging made with a polymeric mixture of gelatin and corn starch. The films produced were characterized by scanning electron microscopy (SEM), Fourier transform infrared (FTIR) spectroscopy, thickness, mechanical properties, water vapor permeability (WVP), solubility, water contact angle, optical properties, in vitro bioactive activity, and biodegradability. A higher concentration of total phenolic compounds (101.61 mg GAE/g) was found for the condition where alcohol content and extraction time were 65% and 20 min, respectively. Pecan nut cake (PNC( extracts did not influence the film's tensile strength, and elongation at break was tightly increased by adding 10-20% extracts. The film's characterization pointed to more than 67% solubility, and adding PNC extract implied more hydrophilic surfaces (contact angles lower than 65°). Furthermore, the film opacity showed a linear relation with PNC extract concentration, and a higher luminosity (L*) was observed for the film without extract. Furthermore, the antioxidant activity of the films was enhanced with the addition of PNC extracts, and complete biodegradation was observed until the ninth day. Therefore, biodegradable films prepared from a mixture of gelatin starch and enriched with PNC extracts showed excellent mechanical properties and potential as carriers of antioxidant compounds, allowing us to propose their use as active packing.

Effect of corn stigma extract on physical and antioxidant properties of biodegradable and edible gelatin and corn starch films.

The development of bio-based food packaging with antioxidant properties is an important research topic and has gained prominence these days. In this study, bioactive films were developed based gelatin-corn starch (GCS) incorporated with corn stigma extract (CSE) at different concentrations (15% and 25%; w/v). In preliminary tests, the extract maintained cell viability above 90% indicating that it is safe for application as an active ingredient. Insertion of the extract did not influence the thickness of the films but caused a slight change in optical properties. Scanning electron microscopy (SEM) analysis revealed interactions between the extract's bioactive compounds with gelatin and corn starch compounds, which may have improved the mechanical properties (elongation at break, Young's modulus). The addition of 25% corn stigma extract increased the contact angle, giving the film a hydrophobic character. Furthermore, at this concentration, a 15% reduction in water vapor permeability was observed. The elaborated films showed complete biodegradability before the tenth day of the study. It can be inferred that the films with corn stigma extract have good antioxidant properties, indicating that they can be used as an ingredient for food packaging.

Performance of Gelatin Films Reinforced with Cloisite Na+ and Black Pepper Essential Oil Loaded Nanoemulsion.

The concern about consuming eco-friendly products has motivated research in the development of new materials. Therefore, films based on natural polymers have been used to replace traditional polymers. This study consists of a production of films based on gelatin reinforced with black pepper essential oil-loaded nanoemulsions and Cloisite Na+. The films were characterized by water vapor permeability, mechanical and thermal properties, surface contact angle, X-ray diffraction and scanning electron microscopy. It was observed that the films containing the nanoemulsion have higher permeability values and an increase in their mechanical resistance. The addition of nanoclay contributed to an increase in the surface hydrophobicity of the film and an increase in the tensile strength, at break, by about 150%. The addition of essential oil nanoemulsions led to an increase in thermal stability. The presence of clay dispersion contributed to the formation of a surface that was slightly rougher and grainier. The addition of the black pepper essential oil nanoemulsion resulted in an increase in porosity of the gelatin matrix. Through X-ray diffraction analysis, it was possible to conclude that both the polymeric gelatin matrix and the essential oils nanoemulsion are intercalated with the clay dispersion.

Investigating the Barrier Activity of Novel, Human Enhancer-Blocking Chromatin Insulators for Hematopoietic Stem Cell Gene Therapy.

Despite the unequivocal success of hematopoietic stem and progenitor cell gene therapy, limitations still exist including genotoxicity and variegation/silencing of transgene expression. A class of DNA regulatory elements known as chromatin insulators (CIs) can mitigate both vector transcriptional silencing (barrier CIs) and vector-induced genotoxicity (enhancer-blocking CIs) and have been proposed as genetic modulators to minimize unwanted vector/genome interactions. Recently, a number of human, small-sized, and compact CIs bearing strong enhancer-blocking activity were identified. To ultimately uncover an ideal CI with a dual, enhancer-blocking and barrier activity, we interrogated these elements in vitro and in vivo. After initial screening of a series of these enhancer-blocking insulators for potential barrier activity, we identified three distinct categories with no, partial, or full protection against transgene silencing. Subsequently, the two CIs with full barrier activity (B4 and C1) were tested for their ability to protect against position effects in primary cells, after incorporation into lentiviral vectors (LVs) and transduction of human CD34+ cells. B4 and C1 did not adversely affect vector titers due to their small size, while they performed as strong barrier insulators in CD34+ cells, both in vitro and in vivo, shielding transgene's long-term expression, more robustly when placed in the forward orientation. Overall, the incorporation of these dual-functioning elements into therapeutic viral vectors will potentially provide a new generation of safer and more efficient LVs for all hematopoietic stem cell gene therapy applications.

Upcycling Microbial Cellulose Scraps into Nanowhiskers with Engineered Performance as Fillers in All-Cellulose Composites.

Cellulose is everywhere and renovates in nature continuously and rapidly, while petroleum does not. Unlike the latter, cellulose biodegrades and may represent a carbon sink. Inspired by the multiscale architecture of cellulose, we report on all-cellulose composites comprising cellulose ether as a matrix and highly pure bacterial cellulose nanocrystals (BCNCs) as fillers. Optimum performance as a packaging material was achieved by engineering BCNC surface chemistry as well as the filler-in-matrix dispersion, targeting the replacement of unsustainable, fossil-derived plastics intended for single-use applications. Cost could pose a hurdle, eliminated through the valorization of underutilized scraps from industrial operations, which is also in line with the circular bioeconomy in terms of the integral use of biomass. As far as performance, the optically transparent hydroxypropyl methylcellulose (HPMC) films presented improved tensile strength (from 61 ± 6 to 86 ± 9 MPa) and Young's modulus (from 1.5 ± 0.2 to 2.7 ± 0.4 GPa) while reduced elongation at break (from 15 ± 2 to 12 ± 2%) and water vapor permeability (from 0.40 ± 0.02 to 0.31 ± 0.01 g mm h-1 m-2 kPa-1) when filled with only 5 wt % of (120 ± 31) nm long, (13 ± 3) nm wide, 88% crystalline BCNC. This dual, win-win effect of BCNCs on the mechanical and barrier properties of HPMC films was enabled by a suitable dispersion state, achieved via high-energy mixing, and quenched by casting. This study adds to the current literature on all-cellulose composites and helps pave the route for the technical and economical feasibilities of replacing non-renewable, non-biodegradable plastics in short-term applications by materials that are both renewable and biodegradable, that are also produced through green protocols and isolated from surplus biomass, and that still perform similarly or even better.

Reduced expression of L-selectin in T-cells correlates with relative lymphocyte increase in patients with RRMS treated with natalizumab - functional implication towards PML risk.

Objectives: Natalizumab (NTZ), a treatment indicated for patients with highly active Relapsing - Remitting Multiple Sclerosis (RRMS), is known to induce increased relative frequency of lymphocytes. Progressive Multifocal Leukoencephalitis (PML) is a rare but serious adverse event related to NTZ. Moreover, reduced L-selectin (CD62L) expression in T-cells in cryopreserved samples of patients with RRMS under NTZ has been proposed as a biomarker of pre-PML state. We explore the association between L-selectin expression in T-cells and hematological parameters in freshly processed samples of patients with RRMS under NTZ.Methods: We studied L-selectin expression in patients with: RRMS under NTZ (n=34), fingolimod (FTY, n=14), interferon-beta (IFNß, n=22), glatiramer acetate (GA, N=17); in 9 patients with secondary progressive (SP) MS and in 6 healthy controls. Twenty-two patients under NTZ and 6 patients under FTY were followed for 18 months. One NTZ-treated patient developed PML during the study.Results: Patients under NTZ exhibited increased relative frequency of lymphocytes (40.02±1.45) compared to patients under first-line treatment (30.57±1.68, p<0.001) and to patients with SPMS (29±1.56, p=0.02), and a lower mean L-selectin expression in (69.39±1.73) compared to patients under first-line treatment (79.1±1.17, p=0.003). A negative correlation between the relative frequency of CD4+CD62L+ T-cells and the absolute lymphocyte counts (Pearson's r=0.367, p=0.033) was observed.Discussion: We hereby provide mechanistic insight in a possible pathway implicated in NTZ-related PML risk. These results further underline the need for thorough validation of L-selectin expression in T-cells as a potential pre-PML biomarker.

Combining Cupuassu (Theobroma grandiflorum) Puree, Pectin, and Chitosan Nanoparticles into Novel Edible Films for Food Packaging Applications.

Every year, the residues generated by the disposal of packaging materials produced from fossil fuels have been growing, denoting a major environmental problem that can be mitigated by the development of biodegradable materials from natural polymers, particularly edible films. This work aimed at the development of pectin films added by cupuassu puree and chitosan nanoparticles and to evaluate the improvement of the physical-mechanical performance of the composite films. The nanostructures displayed an average size of 110 nm and a zeta potential of approximately +40 mV. The films were produced by casting, and they exhibited manageability, homogeneity, and continuity. Based upon the mechanical analysis of maximum stress and elongation, it was concluded that the nanoparticles functioned as fillers, increasing the toughness of the pectin films. Water vapor permeability assays demonstrated that the nanostructured films containing cupuassu exhibited improved barrier properties. The glass transition temperature of the films was not strongly affected by the addition of nanoparticles. Conversely, the initial degradation temperature decreased with the addition of nanoparticles and cupuassu puree. The outcomes of this research pave a new route for the development of nonconventional food packaging materials.

Induction of apoptosis in CD4(+) T-cells is linked with optimal treatment response in patients with relapsing-remitting multiple sclerosis treated with Glatiramer acetate.

BACKGROUND: Induction of T-cell apoptosis constitutes a mechanism of action for Glatiramer Acetate (GA). We investigated whether activation of apoptotic T-cell death may be indicative of optimal treatment response in patients with relapsing-remitting Multiple Sclerosis (RRMS), with respect to radiological activity. METHODS: We studied apoptotic markers on blood T-cells of forty patients with RRMS, 19 patients under GA and 21 patients under interferon-ß (IFNß), by flow cytometry. Patients were relapse-free and were further classified into optimal and sub-optimal responders based on radiological activity. Eighteen patients (8 patients under GA and 10 patients under IFNß were additionally evaluated at a 12-month follow-up and were relapse- and radiological activity-free. For these patients, apoptosis was also evaluated by molecular techniques. RESULTS: At inclusion, optimal responders to GA exhibited increased (23.6 ±â€¯1.976) relative % frequency of CD4(+)AnnexinV(+)7AAD(-) T-cells, compared to sub-optimal responders (14.478 ±â€¯1.204, p = 0.001). Similarly, relative % frequency of caspase-3(+) T-cells was 1.517 ±â€¯0.436 versus 0.45 ±â€¯0.149 (p = 0.041), respectively. Anti-apoptotic molecule bcl-2 showed an inverse pattern 4.532 ±â€¯1.321 versus 13.094 ±â€¯3.987, p = 0.044, respectively. These differences were not evident for IFNß-treated patients. CONCLUSIONS: T-cell apoptotic markers may be applied as a biomarker useful in evaluating optimal treatment response under GA, thus allowing for personalized treatment decisions.