Surface passivation for highly active, selective, stable, and scalable CO2 electroreduction

Electrochemical conversion of CO2 to formic acid using Bismuth catalysts is one the most promising pathways for industrialization. However, it is still difficult to achieve high formic acid production at wide voltage intervals and industrial current densities because the Bi catalysts are often poisoned by oxygenated species. Herein, we report a Bi3S2 nanowire-ascorbic acid hybrid catalyst that simultaneously improves formic acid selectivity, activity, and stability at high applied voltages. Specifically, a more than 95% faraday efficiency was achieved for the formate formation over a wide potential range above 1.0 V and at ampere-level current densities. The observed excellent catalytic performance was attributable to a unique reconstruction mechanism to form more defective sites while the ascorbic acid layer further stabilized the defective sites by trapping the poisoning hydroxyl groups. When used in an all-solid-state reactor system, the newly developed catalyst achieved efficient production of pure formic acid over 120 hours at 50 mA cm–2 (200 mA cell current)

Development of silk fibroin-derived nanofibrous drug delivery system in supercritical CO2

A silk fibroin (SF)-derived nanofibrous drug delivery system was fabricated by solution-enhanced dispersion via supercritical CO2 (SEDS) (20 MPa pressure, 8 mL/min flow rate, 35 °C temperature) in this study. Curcumin (CM) was used as a water-insoluble drug model. Nanofibrous structure with controllable fiber diameter (<100 nm) was obtained, and inter-molecular hydrogen bonds were formed between CM and SF; the crystallinity of the incorporated CM was remarkably decreased, which led to a significant enhancement in solubility of incorporated CM. In conclusion, SEDS could be developed to fabricate polymeric nanofibrous drug delivery system.Institute of Textiles and Clothin

ELECTIVE DELIVERY VERSUS EXPECTANT MANAGEMENT FOR GASTROSCHISIS: A SYSTEMIC REVIEW AND META-ANALYSIS

INTRODUCTION: The optimal timing of delivery for pregnancies complicated by foetal gastroschisis remains controversial. Therefore, the aim of this study is to find whether elective or expectant delivery is associated with improved neonatal outcome. MATERIALS AND METHODS: MEDLINE and Embase databases were searched for studies up to 2021 that reported timing of delivery for foetal gastroschisis. A systematic review and meta-analysis were then performed in group 1: moderately preterm (Gestational age, [GA] 34-35 weeks) elective delivery versus expectant management after GA 34-35 weeks; and group 2: near-term (GA 36-37 weeks) elective delivery versus expectant management after GA 36-37 weeks. The following clinical outcomes were evaluated: length of stay (LOS), total parenteral nutrition (TPN) days, bowel morbidity (atresia, perforation, and volvulus), sepsis, time of first feeding, short gut syndrome and respirator days, and mortality. RESULTS: Two randomised controlled trails (RCT)s and eight retrospective cohort studies were included, comprising of 629 participants. Moderately preterm elective delivery failed to improve clinical outcomes. However, near-term elective delivery significantly reduced bowel morbidity (7.4% vs 15.4%, RR=0.37; CI 0.18, 0.74; p=0.005; I2=0%) and TPN days (MD=-13.44 days; CI -26.68, -0.20; p=0.05; I2=45%) compared to expectant delivery. The mean LOS was 39.2 days after near-term delivery and 48.7 days in the expectant group (p=0.06). CONCLUSIONS: Based on the data analysed, near-term elective delivery (GA 36-37 weeks) appears to be the optimal timing for delivery of pregnancies complicated by foetal gastroschisis as it is associated with less bowel morbidity and shorter TPN days. However, more RCTs are necessary to better validate these findings.  

Biodegradable weft-knitted intestinal stents: Fabrication and physical changes investigation in vitro degradation

Biodegradable stents can alleviate intestinal obstruction and stenosis in patients. The objective of this study was to develop a biodegradable polydioxanone (PDO) stent using weft-knitting technology and then investigate its biodegradation behaviors in vitro. PDO monofilament with linear density of 100 ± 10 tex was knitted into a tubular stent using a tubular weft-knitting machine. The physical and mechanical properties were evaluated according to the British standard BS EN 13895:2003 and ISO 7198:1998. The biodegradation behaviors of PDO weft-knitted stent in a phosphate buffer solution (pH = 6.8 ± 0.2, 37 ± 0.5°C) were then investigated. The results showed that the stent maintained more than 60% of its original radial force above 12 weeks. During the 16 weeks of degradation, weight, crystallization, and pH change indicated the degradation medium was diffused into the chain segments of low molecular weight due to the rupture of ester bonds in the monofilament. Fourier transform infrared spectroscopy results demonstrated that the chemical structure of PDO polymer is stable during the in vitro degradation. In conclusion, this biodegradable stent can find valuable applications in treatment of intestinal obstruction and stenosis clinically.Institute of Textiles and Clothin

Toxicity study of isolated polypeptide from wool hydrolysate

The cytotoxicity of wool polypeptide has been evaluated by both cell and animal models. Wool was dissolved in sodium hydroxide solution, the pH value of the solution was adjusted to 5.55 and the precipitate was harvested as wool polypeptide. The spray-dried polypeptide was collected as powders and characterized by SEM, FTIR and TG-DSC. The cell culturing results showed that wool polypeptide had no obvious negative effect on cell viability in vitro. Both acute oral toxicity and subacute 30-day oral toxicology studies showed that wool polypeptide had no influence on body weight, feed consumption, blood chemistry, and hematology at any dose levels. There were no treatment related findings on gross or detailed necroscopy, organ weights, organ/body weight ratios and histology. Our study indicated the absence of toxicity in wool polypeptide and supported its safe use as a food ingredient or drug carrier.Institute of Textiles and Clothin

Generation of biofunctional and biodegradable electrospun nanofibers composed of poly (L-lactic acid) and wool isoelectric precipitate

The present study introduced a novel biocompatible electrospun membrane composed of poly (l-lactic acid) (PLLA) and water-insoluble keratin precipitates from wool hydrolyzed solution. Ultrafine nanofibrous membranes were successfully prepared by electrospinning the blend of PLLA and keratin/alcohol suspension. Uniform structure of the composite nanofibers was observed by scanning electron microscopy. Transmission electron microscopy pictures indicated keratin was evenly distributed within the composite fibers. The result of Fourier transform infrared (FT-IR) spectra revealed the composition of the keratin/PLLA membrane. X-ray differential spectroscopy suggested that higher crystallinity can be observed from keratin/PLLA composite nanofibers than pristine keratin precipitates. The thermogravimetric analyzer spectra indicated that keratin/PLLA composite fibers possessed more constant thermostability than pristine keratin precipitates. The in vitro degradation of keratin/PLLA composite nanofibers was evaluated by FT-IR spectra and ultraviolet spectra. The experimental results showed that the degradation rate was fast on the first day and slow in the following period. The biocompatibility of the keratin/PLLA composite membrane was examined by MTT assay and the cell proliferation profile was observed by fluorescent micrographs. The results indicated that with the promoting effect on cell adherence and proliferation, this composite material was suitable as a biomedical fabrics candidate for use in drug delivery vehicle and tissue engineering scaffolds

Oligosaccharide attenuates aging‐related liver dysfunction by activating Nrf2 antioxidant signaling

Abstract Chitosan oligosaccharide (COS) is the depolymerized product of chitosan possessing various biological activities and protective effects against inflammation and oxidative injury. The aim of the present study was to investigate the antioxidant effects of COS supplements on aging‐related liver dysfunction. We found that COS treatment significantly attenuated elevated liver function biomarkers and oxidative stress biomarkers and decreased antioxidative enzyme activities in liver tissues in D‐galactose (D‐gal)‐treated mice. Furthermore, COS treatment significantly upregulated the expression of Nrf2 and its downstream target genes HO‐1, NQO1, and CAT. Moreover, in vitro experiments showed that COS treatment played a vital role in protecting H2O2‐exposed L02 cells against oxidative stress by activating Nrf2 antioxidant signaling. These data indicate that COS could protect against D‐gal‐induced hepatic aging by activating Nrf2 antioxidant signaling, which may provide novel applications for the prevention and treatment of aging‐related hepatic dysfunction

Disruptive NADSYN1 Variants Implicated in Congenital Vertebral Malformations

Genetic perturbations in nicotinamide adenine dinucleotide de novo (NAD) synthesis pathway predispose individuals to congenital birth defects. The NADSYN1 encodes the final enzyme in the de novo NAD synthesis pathway and, therefore, plays an important role in NAD metabolism and organ embryogenesis. Biallelic mutations in the NADSYN1 gene have been reported to be causative of congenital organ defects known as VCRL syndrome (Vertebral-Cardiac-Renal-Limb syndrome). Here, we analyzed the genetic variants in NADSYN1 in an exome-sequenced cohort consisting of patients with congenital vertebral malformations (CVMs). A total number of eight variants in NADSYN1, including two truncating variants and six missense variants, were identified in nine unrelated patients. All enrolled patients presented multiple organ defects, with the involvement of either the heart, kidney, limbs, or liver, as well as intraspinal deformities. An in vitro assay using COS-7 cells demonstrated either significantly reduced protein levels or disrupted enzymatic activity of the identified variants. Our findings demonstrated that functional variants in NADSYN1 were involved in the complex genetic etiology of CVMs and provided further evidence for the causative NADSYN1 variants in congenital NAD Deficiency Disorder