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  • Danielsen Cotton posted an update 1 week, 6 days ago

    Graphene oxide (GO) has recently been highlighted as a promising multipurpose two-dimensional material. However, free-standing graphene oxide films suffer from poor strength and flexibility, which limits scaling-up of production and lifetime structural robustness in applications. Inspired by the relationship between the organic and inorganic components of the hierarchical structure of nacre found in mollusk shells, we have fabricated self-assembled, layered graphene-based composite films. The organic phase of our composite is produced via environmentally friendly and economical methods based on bacterial production of γ-poly(glutamic acid) (PGA). Composite films made of GO, PGA, and divalent cations (Ca2+) were prepared through a slow solvent evaporation method at ambient temperature, resulting in a nacre-like layered structure. These biobased nanocomposite films showed impressive mechanical properties, which resulted from a synergistic combination of hydrogen bonding with the bacterially produced PGA and ionic bonding with calcium ions (Ca2+). The GO/PGA/Ca2+ composite films possessed a high strength of 150 ± 51.9 MPa and a high Young’s modulus of 21.4 ± 8.7 GPa, which represents an increase of 120% and over 70% with respect to pure GO films. We provide rational design strategies for the production of graphene-based films with improved mechanical performance, which can be applied in filtration purification of wastewater in the paper, food, beverage, pigment, and pharmaceuticals industries, as well as for manufacturing of functional membranes and surface coatings.An efficient, safe, and environmentally friendly tertiary butyl hydrogen peroxide (TBHP)-mediated rearrangement of aryl/alkylidene malononitrile with anilines has been developed with in situ generation of HCN as the cyanide source for the synthesis of substituted α-aminonitriles and α-aminoamide. A diverse set of α-aminonitriles and α-aminoamides was efficiently synthesized in good to excellent yields. This method features a broad substrate scope and good functional group tolerance, and the in situ-generated HCN bypasses the use of an external cyanide source.The cell membrane possesses an extensive library of proteins, carbohydrates, and lipids that control a significant portion of inter- and intracellular functions, including signaling, proliferation, migration, and adhesion, among others. Augmenting the cell surface composition would open possibilities for advances in therapy, tissue engineering, and probing fundamental cell processes. While genetic engineering has proven effective for many in vitro applications, these techniques result in irreversible changes to cells and are difficult to apply in vivo. Another approach is to instead attach exogenous functional groups to the cell membrane without changing the genetic nature of the cell. This review focuses on more recent approaches of nongenetic methods of cell surface modification through metabolic pathways, anchorage by hydrophobic interactions, and chemical conjugation. Benefits and drawbacks of each approach are considered, followed by a discussion of potential applications for nongenetic cell surface modification and an outlook on the future of the field.Hyperuricemia seriously jeopardizes human health by increasing the risk of several diseases, such as gout and stroke. Nuciferine is able to alleviate hyperuricemia significantly. However, the underlying metabolic regulation mechanism remains unknown. To understand the metabolic effects of nuciferine on hyperuricemia by establishing a rat model of rapid hyperuricemia, 1H NMR and liquid chromatography-mass spectrometry were used to conduct nontargeted metabolomics studies. A total of 21 metabolites were authenticated in plasma and urine to be closely related with hyperuricemia, which were mainly correlated to the six metabolic pathways. Moreover, 16S rRNA analysis indicated that diversified intestinal microorganisms are closely related to changes in differential metabolites, especially bacteria from Firmicutes and Bacteroidetes. We propose that indoxyl sulfate and N-acetylglutamate in urine may be the potential biomarkers besides uric acid for early diagnosis and prevention of hyperuricemia. Gut microbiological analysis found that changes in the gut microbiota are closely related to these metabolites.Long non-coding RNA (lncRNA) KCNQ1 and opposite strand/antisense transcript 1 (KCNQ1OT1) have been validated to be carcinogenic in several cancers. However, the role of KCNQ1OT1 in regulating the malignant biological behavior and radiotherapy resistance of cervical cancer (CC) remains largely unknown. Avotaciclib molecular weight Quantitative real time-polymerase chain reaction (qRT-PCR) was carried out to detect KCNQ1OT1 and miR-491-5p expression in CC tissues and cells. Pyruvate kinase M1/2 (PKM2) expression was detected by Western blot. CC cell proliferation, movement, migration and invasion were monitored by CCK-8, scratch healing and Transwell assay, respectively. The CC cell colony survival was detected by colony formation assay under different doses of radiation. Dual luciferase reporter gene assay, pull-down assay and RIP assay were employed to verify the targeting relationship between KCNQ1OT1, miR-491-5p and PKM2. In this study, KCNQ1OT1 was significantly up-regulated in CC patient cancerous tissues and cell lines, and its high expression was significantly related to tumor volume increase and poor differentiation. KCNQ1OT1 overexpression significantly promoted CC cell proliferation, metastasis and radioresistance. On the contrary, KCNQ1OT1 knockdown compared to the control group inhibited the above biological behavior of CC cells. The underlying mechanism suggested that KCNQ1OT1 promoted progression and radioresistance of CC by modulating the miR-491-5p/PKM2 axis. In conclusion, KCNQ1OT1 enhances CC cell progression through the miR-491-5p/PKM2 axis.Terrestrial gastropods express metal-selective metallothioneins (MTs) by which they handle metal ions such as Zn2+ , Cd2+ , and Cu+ /Cu2+ through separate metabolic pathways. At the same time, they depend on the availability of sufficient amounts of Cu as an essential constituent of their respiratory protein, hemocyanin (Hc). It was, therefore, suggested that in snails Cu-dependent MT and Hc pathways might be metabolically connected. In fact, the Cu-specific snail MT (CuMT) is exclusively expressed in rhogocytes, a particular molluscan cell type present in the hemocoel and connective tissues. Snail rhogocytes are also the sites of Hc synthesis. In the present study, possible interactions between the metal-regulatory and detoxifying activity of MTs and the Cu demand of Hc isoforms was explored in the edible snail Cornu aspersum, one of the most common European helicid land snails. This species possesses CdMT and CuMT isoforms involved in metal-selective physiological tasks. In addition, C. aspersum expresses three different Hc isoforms (CaH ɑD, CaH ɑN, CaH β). We have examined the effect of Cd2+ and Cu2+ exposure on metal accumulation in the midgut gland and mantle of C. aspersum, testing the impact of these metals on transcriptional upregulation of CdMT, CuMT, and the three Hc genes in the two organs. We found that the CuMT and CaH ɑD genes exhibit an organ-specific transcriptional upregulation in the midgut gland of Cu-exposed snails. These results are discussed in view of possible interrelationships between the metal-selective activity of snail MT isoforms and the synthesis and metabolism of Hc isoforms.

    Racial/ethnic minorities experience more severe outcomes of coronavirus disease 2019 (COVID-19) in the general US population. This study was undertaken to examine the association between race/ethnicity and COVID-19 hospitalization, ventilation status, and mortality in people with rheumatic disease.

    US patients with rheumatic disease and COVID-19 were entered into the COVID-19 Global Rheumatology Alliance physician registry between March 24, 2020 and August 26, 2020 were included. Race/ethnicity was defined as White, African American, Latinx, Asian, or other/mixed race. Outcome measures included hospitalization, requirement for ventilatory support, and death. Multivariable regression models were used to estimate odds ratios (ORs) and 95% confidence intervals (95% CIs) adjusted for age, sex, smoking status, rheumatic disease diagnosis, comorbidities, medication use prior to infection, and rheumatic disease activity.

    A total of 1,324 patients were included, of whom 36% were hospitalized and 6% died; 26% ofc minorities with rheumatic disease and COVID-19 had increased odds of hospitalization and ventilatory support. These results illustrate significant health disparities related to COVID-19 in people with rheumatic diseases. The rheumatology community should proactively address the needs of patients currently experiencing inequitable health outcomes during the pandemic.Arbutin, a glycoside extracted from the plant Arctostaphylos uva-ursi, has been previously reported to possess antioxidant, anti-inflammatory and anticancer effects. Here, we investigated whether arbutin affects the proliferation of the cells of the osteosarcoma (OS) cell lines MG-63 and SW1353. Arbutin suppressed OS cell viability in a dose- and time-dependent manner, as shown by Cell Counting Kit-8 assay. Furthermore, arbutin exposure decreased the protein levels of MTHFD1L, CCND1 and phosphorylated-protein kinase B (AKT)/phosphorylated-mammalian target of rapamycin (mTOR). Potential upstream miRNAs of MTHFD1L were predicted using TargetScan, PICTAR5, miRanda and miRWalk. We performed luciferase activity assays to show that miR-338-3p directly targets and negatively regulates the expression of MTHFD1L. Knockdown of miR-338-3p promoted cell invasion, migration and proliferation in arbutin-treated OS cells via MTHFD1L. In summary, our data suggest that arbutin inhibits OS cell proliferation, migration and invasion via miR-338-3p/MTHFD1L and by inactivating the AKT/mTOR pathway.

    Total gastrectomy with splenectomy (TGS) is sometimes performed for treatment of locally advanced gastric cancer invading the greater curvature because metastasis to splenic hilar nodes is expected. Despite the widespread use of laparoscopic procedures, the feasibility of laparoscopic TGS (LTGS) has been scarcely reported because of its technical difficulties.

    This retrospective single-institutional study included 93 consecutive patients with proximal advanced gastric cancer who underwent either LTGS or open TGS (OTGS) from 2010 to 2018. The patients who underwent LTGS (n = 12) were compared with a 12 ratio propensity score-matched cohort of patients who underwent OTGS (n = 20). Clinical outcomes were retrospectively reviewed and compared between the two groups.

    The patients’ baseline characteristics were well balanced between the two groups. The operating time was longer (332.5 vs 222.5 minutes, P < .01) but the blood loss volume was smaller (34.5 vs 426 mL, P < .01) in the LTGS than OTGS group. The incidence of postoperative morbidity (≥ Clavien-Dindo grade III) was much lower (0.0% vs 36.8%, P = .02) and the median postoperative hospital stay was shorter (9 vs 11 days, P < .01) in the LTGS than OTGS group. The median number of harvested No. 10 or 11 days lymph nodes was equivalent between the two groups.

    Although TGS is not a common procedure, LTGS may be safely performed in selected patients when carried out by an experienced surgical team. The oncological safety remains unclear and needs to be further examined in future trials.

    Although TGS is not a common procedure, LTGS may be safely performed in selected patients when carried out by an experienced surgical team. The oncological safety remains unclear and needs to be further examined in future trials.