Niebuhrvinter2502

Bacterial nanocellulose (BNC) is characterized by high purity and excellent mechanical properties; however, its production is constrained by low yield. Therefore, efforts aimed at improving its yield and material properties are imperative. This study investigated the effect of adding different concentrations (0%, 0.5%, and 1.0%) of cellulose nanocrystal (CNC) in Hestrin-Schramm modified medium on the yield and properties of BNC produced by Komagataeibacter sp. SFCB22-18. The BNC yield increased as following an increase in added CNC concentration. Also, the morphology, structure, crystallinity, thermal stability, and mechanical properties of BNC improved after CNC incorporation. A low CNC concentration (0.1%) favored mechanical strength, whereas 0.5% gave the optimum morphology, structural, and thermal stability. These results showed that modifying BNC with CNC could help increase yield and improve its properties, and thus; the potentiality of BNC in various applications would be much enhanced.In this work, lignin-based carbon nanofibers (LCNFs) were for the first time served as substrate for in-situ electrodeposition of polyaniline (PANI) and tested as pseudocapacitor. Two LCNFs with different lignin ratios were designed to distinguish their morphology and structural properties. Next, PANI deposition mechanisms on both LCNFs were investigated and the electrochemical performance of the resulting LCNF/PANIs were evaluated. It was found although LCNF2 was composed of less uniform nanofibers due to more presence of lignin in precursor dope, it had higher tensile strength/modulus than LCNF1 (strength 34.3MPa to 24.2 MPa; Modulus 2.40 GPa to 1.45GPa) and was more cost-effective. Decarboxylase inhibitor Particularly, the beaded fibers on LCNF2 contributes to the deposition of PANI with higher specific mass capacitance (612.8 F g-1 to 547.0 F g-1). Upon assembling into solid-state supercapacitors, the Cm of LCNF2/PANI device was determined to be 229 F g-1 and the maximum energy density was 11.13Wh kg-1 at a power density of 0.08 kW kg-1. This work showed LCNF produced from renewable and low-cost lignin could be directly used as substrate for PANI deposition. Moreover, the composition in spinning dope played an important role in determining the performances of resulting pseudocapacitors.The main purpose of this study was to increase shelf life of banana using active hydrogel. For this purpose, carboxymethylcellulose/nanofiber cellulose/potassium permanganate (CMC/NFC/KMnO4) hydrogel film was prepared. The morphology and physicochemical properties of CMC hydrogels was investigated. The prepared films were used as humidity/ethylene absorbent in banana packaging for 30 days at 0 and 25 °C. The physical, mechanical and sensory properties of bananas were studied during storage. SEM images confirmed the presence of nanofibers in the hydrogel structure. NFC and KMnO4 increased the tensile strength of the film and decreased its elongation. On the 15th day of storage, bananas packaged with optimal active hydrogel (CMC/NFC/KMnO4) at 25 °C had a flavor of 3 and a general acceptance of 3.5, while control bananas had a flavor of 0.5 and a general acceptance of less than 1. On the 30th day of storage, bananas packaged with optimal active hydrogel at 25 °C had a toughness of 4 (N·s) and a firmness of 20 (N), while control bananas had a toughness of about 1 (N·s) and a firmness of about 8 (N). On the 30th day of storage, the humidity inside the package of bananas packed with the optimum active hydrogel at 25 °C was 59.5%, while the humidity in the control packages was 85%, indicating that the hydrogel was able to absorb the moisture inside the package. Totally it can be said that CMC/NFC/KmnO4 hydrogel can increase shelf life of a banana by simultaneously controlling ethylene and humidity in food packaging.In this study, a novel bio-based flame retardant LC-PA is prepared by the Mannich reaction between phytic acid (PA) and L-citrulline (LC). LC-PA is combined with tannic acid (TA) and introduced into PLA to improve fire performance and accelerate biodegradability. Compared with control PLA, the PLA composite containing 10% LC-PA/TA increases the LOI value to 26.9%, reaches a V-0 rating in the UL-94 test, and reduces the peak heat release rate and total heat release by 24.5% and 21.1%, respectively. More importantly, the introduction of LC-PA/TA accelerates the degradation rate of PLA in soil, which is of significance for biodegradable materials. The addition of LC-PA/TA can attract water and provide a suitable energy source for microbial proliferation, accelerating the hydrolysis and microbial degradation of PLA. This work provides a practical approach for high flame retardancy and rapid biodegradability in the soil to the bio-based polymer.Drug delivery systems are explained as methods to deliver a specific drug to desired organs, tissues, and cells for drug release to diseases treatment. Recently, considerable development has been interested in stimuli-responsive nano-systems, which respond to the essential pathological and physicochemical issues in diseased sites. During the last decades, researchers in the world presented, investigated, and implemented novel different nanomaterials with a focus on developing drug delivery. Polysaccharides including chitosan, alginate, hyaluronic acid, gums, and cellulose, as natural bio-materials, are suitable candidates for designing and formulations of these nano-systems because of the outstanding merits such as bio-compatibility, bio-degradability, non-toxicity, and gelling characteristics. On the other side, nanoparticles including metals (Au, Ag), metal oxides (Fe3O4, ZnO, CuO), or non-metal oxides (SiO2) and also, layered double hydroxides nanostructures have appealed significant consideration in the fields of biomedical therapeutics and cancer therapy owing to the bio-compatibility, great surface area, good chemical and mechanical features, and also proper magnetic characteristics. This comprehensive review provides an overview of current advancements in drug delivery strategies, and manufacturing methods using chitosan, alginate, hyaluronic acid, gums, and also, metals, metal oxides, non-metal oxides, and LDHs for delivery system uses.

Young adults are now considered major spreaders of COVID-19 disease. Although most young individuals suffer from mild to moderate disease, there are concerns of long-term adverse health effects. The impact of COVID-19 disease and to which extent population-level immunity against SARS-CoV-2 exist in young adults remain unclear.

To conduct a population-based study on humoral and cellular immunity to SARS-CoV-2 and explore COVID-19 disease characteristics in young adults.

We invited participants from the Swedish BAMSE birth cohort (age 24-27 years) to take part in a COVID-19 follow-up. From 980 participants (October 2020-June 2021), we here present data on SARS-CoV-2 RBD-specific IgM, IgA and IgG titres measured by ELISA and on symptoms and epidemiological factors associated with seropositivity. Further, SARS-CoV-2-specific memory B- and T-cell responses were detected for a subpopulation (n=108) by ELISpot and Fluorospot.

28.4% of subjects were seropositive of which 18.4% were IgM single positive. One in seven seropositive subjects were asymptomatic. Seropositivity associated with use of public transport, but not with sex, asthma, rhinitis, IgE-sensitization, smoking or BMI. In a subset of representative samples, 20.7% and 35.0% had detectable SARS-CoV-2 specific B- and T-cell responses, respectively. B- and T-cell memory responses were clearly associated with seropositivity, but T-cell responses were also detected in 17.2% of seronegative subjects.

Assessment of IgM and T-cell responses may improve population-based estimations of SARS-CoV-2 infection. The pronounced surge of both symptomatic and asymptomatic infections among young adults should imply a continuation of the large-scale vaccination campaign.

Assessment of IgM and T-cell responses may improve population-based estimations of SARS-CoV-2 infection. The pronounced surge of both symptomatic and asymptomatic infections among young adults should imply a continuation of the large-scale vaccination campaign.

Generation of thymic tissue from pluripotent stem cells would provide therapies for acquired and congenital thymic insufficiency states.

We aimed to generate human thymic epithelial progenitors from human embryonic stem cells (hES-TEPs) and to assess their thymopoietic function in vivo.

We differentiated hES-TEPs by mimicking developmental queues with FGF8, Retinoic Acid, Sonic Hedgehog, Noggin and BMP4. We assessed their function in reaggregate cellular grafts under the kidney capsule and in hybrid thymi by incorporating them into fetal swine thymus (SwTHY) grafts implanted under the kidney capsules of immunodeficient mice that received human hematopoietic stem and progenitor and stem cells (hHPSCs) intravenously.

Cultured hES-TEPs expressed FOXN1 and formed colonies expressing EpCAM and both cortical and medullary thymic epithelial cell (TEC) markers. In thymectomized immunodeficient mice receiving hHSPCs, hES-TEPs mixed with human thymic mesenchymal cells supported human T cell development. Hypothesizing that support from non-TEC thymic cells might allow long-term function of hES-TEPs, we injected them into SwTHY tissue, which supports human thymopoiesis in NSG mice receiving hHSPCs. hES-TEPs integrated into SwTHY grafts, enhanced human thymopoiesis and increased peripheral CD4

naive T cell reconstitution.

We have developed and demonstrated in vivo thymopoietic function of hES-TEPs generated with a novel differentiation protocol. The SwTHY hybrid thymus model demonstrates beneficial effects on human thymocyte development of hES-TEPs maturing in the context of a supportive thymic structure.

We have developed and demonstrated in vivo thymopoietic function of hES-TEPs generated with a novel differentiation protocol. The SwTHY hybrid thymus model demonstrates beneficial effects on human thymocyte development of hES-TEPs maturing in the context of a supportive thymic structure.Lipopolysaccharide (LPS) tolerance can reduce the neuroinflammation caused by high fat maternal diets; however, there are no reports that have evaluated the effects of prenatal LPS exposure on the memories of the offspring of high-fat diet fed dams. This study evaluated the effects of prenatal LPS exposure on the inflammatory parameters and redox status in the brain, as well as the object recognition memory of adolescent offspring of Wistar rat dams that were treated with a high-fat diet during gestation and lactation. Female pregnant Wistar rats randomly received a standard diet (17.5% fat) or a high-fat diet (45.0% fat) during gestation and lactation. On gestation days 8, 10, and 12, half of the females in each group were intraperitoneally treated with LPS (0.1 mg.kg-1). After weaning, the male offspring were placed in cages in standard conditions, and at 6 weeks old, animals underwent the novel object recognition test (for short- and long-term memory). The offspring of the high-fat diet fed dams showed increased hippocampus IL-6 levels (21-days-old) and impaired short-term memories. These effects were avoided in the offspring of high-fat diet fed dams submitted to prenatal LPS exposure, which showed greater hippocampus IL-10 levels (at 21- and 50-days-old), increased antioxidant activity (50-days-old) in the hippocampus and prefrontal cortex, without memory impairments (short- and long-term memory). IL-6 has been consistently implicated in memory deficits and as an endogenous mechanism for limiting plasticity, while IL-10 regulates glial activation and has a strong association with improvements in cognitive function. Prenatal LPS exposure preventing the increase of IL-6 in the hippocampus and the impairment to short-term object recognition memory caused by the high-fat maternal diet.