SOD2 promotes the immunosuppressive function of mesenchymal stem cells at the expense of adipocyte differentiation.

The potent immunomodulatory function of mesenchymal stem/stromal cells (MSCs) elicited by proinflammatory cytokines IFN-γ and TNF-α (IT) is critical to resolve inflammation and promote tissue repair. However, little is known about how the immunomodulatory capability of MSCs is related to their differentiation competency in the inflammatory microenvironment. In this study, we demonstrate that the adipocyte differentiation and immunomodulatory function of human adipose tissue-derived MSCs (MSC(AD)s) are mutually exclusive. Mitochondrial reactive oxygen species (mtROS), which promote adipocyte differentiation, were decreased in MSC(AD)s due to IT-induced upregulation of superoxide dismutase 2 (SOD2). Furthermore, knockdown of SOD2 led to enhanced adipogenic differentiation but reduced immunosuppression capability of MSC(AD)s. Interestingly, the adipogenic differentiation was associated with increased mitochondrial biogenesis and upregulation of peroxisome proliferator-activated receptor gamma coactivator-1 alpha (PPARGC1A/PGC-1α) expression. IT inhibited PGC-1α expression and decreased mitochondrial mass but promoted glycolysis in an SOD2-dependent manner. MSC(AD)s lacking SOD2 were compromised in their therapeutic efficacy in DSS-induced colitis in mice. Taken together, these findings indicate that the adipogenic differentiation and immunomodulation of MSC(AD)s may compete for resources in fulfilling the respective biosynthetic needs. Blocking of adipogenic differentiation by mitochondrial antioxidant may represent a novel strategy to enhance the immunosuppressive activity of MSCs in the inflammatory microenvironment.

Thermally Depolymerizable Polyether Electrolytes for Convenient and Low-Cost Recycling of LiTFSI.

Solid polymer electrolytes (SPEs) with LiTFSI (lithium bis(trifluoromethane sulfonimide)) are promising candidates for solid-state batteries, owing to their good interfacial contact with solid electrodes. Here, three copolymerized polyethers were prepared as SPEs, using the catalysts of SnF2 or SnF2 -LiPF6 . The thermal depolymerization of these polyethers was observed at elevated temperatures, which limits their operating temperature ranges. Once the catalyst is removed, the thermal degradation temperatures of these SPEs are raised by 30-55 °C, together with improved thermal performance in cells. For SPEs, the high price of LiTFSI is an obstacle for their large-scale application, and it's recycling is hindered by the strong interaction with polymers. By the thermal depolymerization of polyethers, LiTFSI can be easier reclaimed from above mentioned SPEs and even the commercial PEO(poly(ethylene-oxide)) based SPE in rates of 70-80 %, providing a low-cost strategy for the recycling of LiTFSI.

Has COVID-19 Changed China's Digital Trade?-Implications for Health Economics.

Digital technologies have played a significant role in the defense against the COVID-19 pandemic. This development raises the question of whether digital technologies have helped Chinese exports recover quickly and even grow. To answer this question, we study monthly data on Chinese exports to 40 countries/regions from January 2019 to June 2020 and covering 97 product categories. The study takes the COVID-19 outbreak as a natural experiment and treats digital trade products as the treatment group. Using a generalized difference-in-differences (DID) approach, we empirically investigate how this major global public health crisis and digital trade have influenced Chinese exports. Our empirical analysis reveals that the COVID-19 pandemic has inhibited China's export trade overall, digital trade has significantly promoted trade, and the supply mechanism has played a significant role in promoting the recovery of exports. Heterogeneity tests on destination countries/regions reveal that digital trade has significantly promoted exports to countries/regions with different income levels, with a more significant effect on low-risk destinations than on high-risk destinations. The sector heterogeneity test demonstrates that digital trade has enhanced the export recovery of sectors dealing in necessities for pandemic prevention. Other robustness tests, including parallel trend and placebo tests, support the above conclusions. Finally, we extend the research conclusions and discuss their implication for health economics and the practice of fighting COVID-19.

Portable Oxygen-Sensing Device for the Improved Assessment of Compartment Syndrome and other Hypoxia-Related Conditions.

Measurement of intramuscular oxygen could play a key role in the early diagnosis of acute compartment syndrome, a common condition occurring after severe trauma leading to ischemia and long-term consequences including rhabdomyolysis, limb loss, and death. However, to date, there is no existing oxygen sensor approved for such a purpose. To address the need to improve the assessment of compartment syndrome, a portable fiber-optic device for intramuscular oxygen measurements was developed. The device is based on phosphorescence quenching, where the tip of an optical fiber was coated with a poly(propyl methacrylate) (PPMA) matrix containing a brightly emitting Pt(II)-core porphyrin. The optoelectronic circuit is highly portable and is based on a microspectrometer and a microcontroller readout with a smartphone. Results from an in vivo tourniquet porcine model show that the sensor is sensitive across the physiological oxygen partial pressure range of 0-80 mmHg and exhibits an appropriate and reproducible response to changes in intramuscular oxygen. A commercial laboratory oxygen sensor based on a lifetime measurement did not respond as expected.

Comparison of the Outcomes of Two Operational Methods Used for the Fixation of Calcaneal Fracture.

This study was aimed to compare the outcomes of two operational methods used for the fixation of calcaneal fracture, the open reduction using a plate and the minimally invasive cannulated screw fixations. Thus, we attempted to find out as to which of these fixation regimens was therapeutically superior by assessing improvement in the restoration of foot functioning and estimating the biochemical indices that reflect bone recovery. A total of 492 calcaneal fracture patients admitted in our hospital from February, 2008 to February, 2012 were selected for the study and randomly divided into two groups of 246 cases each. They were treated with either open reduction using a plate or minimally invasive cannulated screw fixation procedures. After the operations, patients were followed up for 2 years and the outcomes including functional restoration of calcaneus, the post-operational complications, and measure of the biochemical indicators of bone recovery were compared. The patients who underwent plate fixation procedure showed the excellent and good rate of 76.8 %. The minimally invasive cannulated screw fixation led to the excellent and good rate of 82.5 %. The angle, width, and height of calcaneus observed in the last follow-up were also improved significantly in the two groups (p < 0.05); however, these outcomes of the two techniques were not significantly different from each other (p > 0.05). The post-operative complications occurred with the rates of 14.2 and 4.9 % in the patients treated with the plate and the minimally invasive cannulated screw fixations, respectively. The length of stay and hospitalization costs in the plate fixation group were 9.16 ± 0.83 days and 12,639.74 ± 2,573.82 Chinese Yuan, respectively. In comparison, in cannulated screw fixation group, the length of hospital stay (7.03 ± 0.52 days) and its cost (6,795.01 ± 996.53 Chinese Yuan) were significantly lower. Serum bone alkaline phosphatase and tartrate-resistant acid phosphatase-5b levels measured at the last follow-up examination were significantly altered (p < 0.05) in the two groups. However, the difference between the outcomes of the two methods was not statistically significant (p > 0.05). Plate screw and the cannulated screw fixations showed equally good therapeutic effect and significantly improved patients' mobility. However, the cannulated screw fixation was superior in terms of post-operative infection-free recovery and economical burden to the patients.

Green and economical synthesis of carbon-coated MoO2 nanocrystallines with highly reversible lithium storage capacity.

Carbon-coated MoO2 nanocrystallines with uniform particle size and carbon-coating morphology have been fabricated by a green and economical hydrothermal route and carbonization process. Glucose here acts as a multifunctional agent, not only as the reducing species to prepare MoO2, but also as the carbonaceous precursor and coating agent to form the carbon-coated and nanoscale MoO2 crystallines. The electrochemical tests demonstrate that the as-synthesized carbon-coated MoO2 nanocrystallines exhibit high capacity and excellent capacity retention as an anode material for lithium-ion batteries. The specific discharge capacity is as high as 790 mA h g(-1) in the first cycle and 730 mA h g(-1) over 50 cycles. The significant enhancement in the electrochemical Li storage performance is attributed to the synergistic effect of the nanocrystallines structure with small particle size and uniform carbon-coating shell, which reduces the diffusion distance for Li-ion and electron, provides high electric conductivity and relieves the volume effect during the cycling.

Assessment of immunoreactive synthetic peptides from the structural proteins of severe acute respiratory syndrome coronavirus.

BACKGROUND: The widespread threat of severe acute respiratory syndrome (SARS) to human life has spawned challenges to develop fast and accurate analytical methods for its early diagnosis and to create a safe antiviral vaccine for preventive use. Consequently, we thoroughly investigated the immunoreactivities with patient sera of a series of synthesized peptides from SARS-coronavirus structural proteins. METHODS: We synthesized 41 peptides ranging in size from 16 to 25 amino acid residues of relatively high hydrophilicity. The immunoreactivities of the peptides with SARS patient sera were determined by ELISA. RESULTS: Four epitopic sites, S599, M137, N66, and N371-404, located in the SARS-coronavirus S, M, and N proteins, respectively, were detected by screening synthesized peptides. Notably, N371 and N385, located at the COOH terminus of the N protein, inhibited binding of antibodies to SARS-coronavirus lysate and bound to antibodies in >94% of samples from SARS study patients. N385 had the highest affinity for forming peptide-antibody complexes with SARS serum. CONCLUSIONS: Five peptides from SARS structural proteins, especially two from the COOH terminus of the N protein, appear to be highly immunogenic and may be useful for serologic assays. The identification of these antigenic peptides contributes to the understanding of the immunogenicity and persistence of SARS coronavirus.