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1.
Nature ; 618(7963): 74-79, 2023 Jun.
Article in English | MEDLINE | ID: mdl-36977463

ABSTRACT

The tunable bandgaps and facile fabrication of perovskites make them attractive for multi-junction photovoltaics1,2. However, light-induced phase segregation limits their efficiency and stability3-5: this occurs in wide-bandgap (>1.65 electron volts) iodide/bromide mixed perovskite absorbers, and becomes even more acute in the top cells of triple-junction solar photovoltaics that require a fully 2.0-electron-volt bandgap absorber2,6. Here we report that lattice distortion in iodide/bromide mixed perovskites is correlated with the suppression of phase segregation, generating an increased ion-migration energy barrier arising from the decreased average interatomic distance between the A-site cation and iodide. Using an approximately 2.0-electron-volt rubidium/caesium mixed-cation inorganic perovskite with large lattice distortion in the top subcell, we fabricated all-perovskite triple-junction solar cells and achieved an efficiency of 24.3 per cent (23.3 per cent certified quasi-steady-state efficiency) with an open-circuit voltage of 3.21 volts. This is, to our knowledge, the first reported certified efficiency for perovskite-based triple-junction solar cells. The triple-junction devices retain 80 per cent of their initial efficiency following 420 hours of operation at the maximum power point.

2.
Biol Pharm Bull ; 43(10): 1455-1462, 2020 Oct 01.
Article in English | MEDLINE | ID: mdl-32759599

ABSTRACT

The aim of this study was to investigate the influences of acute and chronic inflammation on the dynamics of fluid shift of Ringer's solution and hemodynamics in patients during surgery. Thirty-seven patients with the American Society of Anesthesiologists (ASA) grades I-II were enrolled and allocated to two study groups according to the type of disease and operation and inflammation, including patients undergoing emergency appendectomy (Acute group, n = 19) and patients undergoing elective cholecystectomy (Chronic group, n = 18). All of the patients were administered 15 mL/kg of Ringer's lactated (LR) solution at a constant rate over 35 min before the induction of anesthesia. Plasma dilution (PD), volume expansion (VE), volume expansion efficiency (VEE), and extravascular volume (EVV) were calculated based on the concentration of hemoglobin within 2 h post-infusion. Heart rate (HR), arterial blood pressure and urine output were also recorded. PD and VE peaked at the end of infusion, while VEE peaked at the beginning of infusion in all of the patients. After infusion, PD, VE and VEE in the Acute group were all higher than those in the Chronic group (p < 0.05). PD and VE were higher during anesthesia or surgery than during awake or non-surgery (p < 0.001). The mean arterial pressure (MAP) and diastolic pressure (DBP) in the Acute group were significantly lower (p < 0.001) and HR was significantly higher (p < 0.001) than in the Chronic group during the study periods. It was suggested that patients with acute inflammation be treated with individualized fluid therapy during surgery.


Subject(s)
Elective Surgical Procedures/adverse effects , Fluid Therapy/methods , Inflammation/complications , Intraoperative Complications/prevention & control , Ringer's Solution/pharmacokinetics , Adolescent , Adult , Appendectomy/adverse effects , Appendectomy/methods , Arterial Pressure/immunology , Cholecystectomy, Laparoscopic/adverse effects , Cholecystectomy, Laparoscopic/methods , Chronic Disease , Elective Surgical Procedures/methods , Female , Fluid Shifts/immunology , Heart Rate/immunology , Humans , Inflammation/immunology , Intraoperative Complications/diagnosis , Intraoperative Complications/immunology , Male , Middle Aged , Monitoring, Intraoperative , Ringer's Solution/administration & dosage , Treatment Outcome , Young Adult
3.
Macromol Rapid Commun ; 40(24): e1900537, 2019 Dec.
Article in English | MEDLINE | ID: mdl-31762154

ABSTRACT

Mechanically controlled polymerization that employs the mechanical energy to fabricate novel synthetic materials has attracted considerable interest. However, only a few examples have been achieved so far, owing to the limited choices of materials and strategies. Herein, a versatile, liquid metal (LM)-mediated mechanochemical polymerization method (LMMMP) is developed for the air-compatible, robust preparation of polymers in an aqueous solution. This method involves the simultaneous disruption of bulk LMs into micro- and nanodroplets and the combination of monomers into polymers during ultrasonic irradiation. The pristine and reactive LM surface continuously generated by ultrasound endows this polymerization method with excellent oxygen tolerance, high reaction rate, and the ability to produce polymers with high molecular weight from a wide variety of water-soluble monomers. Besides, LM droplets are readily reclaimed and reused for polymerization. The authors envision that the LMMMP promotes the utilization of mechanical energy for the synthesis of functional polymers, constitutes a novel fabrication approach for polymer-LM nanocomposites, and provides new insight into the design of LM-based platforms for polymerization.


Subject(s)
Alloys/chemical synthesis , Gallium/chemistry , Indium/chemistry , Alloys/chemistry , Molecular Structure , Particle Size , Polymerization , Surface Properties
4.
Pharmacology ; 103(5-6): 236-245, 2019.
Article in English | MEDLINE | ID: mdl-30699431

ABSTRACT

BACKGROUND: Systemic oxidative stress has been reported to play a central role in the pathogenesis of kidney function decline. The nuclear factor erythroid 2-related factor 2 (Nrf2)/antioxidant response element (ARE) pathway is one of the important endogenous antioxidant stress pathways in cells. This study aims to investigate whether shenduning granule can ameliorate oxidative stress in kidney tissues by activating the Nrf2/ARE pathway, and explores the detailed underlying mechanism. METHODS: A total of 120 male Sprague-Dawley rats were randomly assigned to the sham-operated and operation groups. Rats in the operation group underwent 5/6 nephrectomy. Two weeks later, rats in the operation group were further randomly divided into 5 groups: model group, low-dose, medium-dose and high-dose shenduning granule groups, and losartan group. Rats in each group were given the same volume of corresponding liquid orally. Serum creatinine (SCr), blood urea nitrogen (BUN), 24-h urinary protein, malondialdehyde (MDA) and superoxide dismutase (SOD), Nrf2, heme oxygenase-1 (HO-1), and γ-glutamyl-cysteine synthetase (γ-GCS) were determined. RESULTS: Shenduning granule could markedly elevate HO-1, NRF2, γ-GCS and SOD (p < 0.05), and significantly decreased MDA, 24-h urinary protein, SCr and BUN in rats (p < 0.05). CONCLUSION: Shenduning granule can improve renal antioxidative stress activity in rats, exhibiting a renoprotective effect. The potential mechanism is likely exerted by the activation of the Nrf2/ARE pathway.


Subject(s)
Kidney Diseases/prevention & control , NF-E2-Related Factor 2/metabolism , Oxidative Stress/drug effects , Plant Extracts/pharmacology , Animals , Antioxidant Response Elements/drug effects , Disease Models, Animal , Dose-Response Relationship, Drug , Kidney Diseases/etiology , Kidney Diseases/physiopathology , Male , Malondialdehyde/metabolism , Plant Extracts/administration & dosage , Plant Extracts/chemistry , Plants, Medicinal/chemistry , Random Allocation , Rats , Rats, Sprague-Dawley , Superoxide Dismutase/metabolism
5.
Biochem Biophys Res Commun ; 478(2): 618-23, 2016 09 16.
Article in English | MEDLINE | ID: mdl-27473656

ABSTRACT

Microbial pathogens enter host cells by injecting effector proteins of the Type III secretion system (T3SS), which facilitate pathogen translocation across the host cell membrane. These effector proteins exert their effects by modulating a variety of host innate immune responses, thereby facilitating bacterial replication and systemic infection. Salmonella enterica serovar typhimurium (S.typhimurium) is a clinically important pathogen that causes food poisoning and gastroenteritis. The SopB effector protein of S. typhimurium, encoded by Salmonella pathogenicity islands (SPI)-1 T3SS, protects host epithelial cells from infection-induced apoptosis. However, how SopB influences apoptosis induction remains unclear. Here, we investigated the mechanism of SopB action in host cells. We found that SopB inhibits infection-induced apoptosis by attenuating the production of reactive oxygen species (ROS) in mitochondria, the crucial organelles for apoptosis initiation. Further investigation revealed that SopB binds to cytosolic tumor necrosis factor receptor associated factor 6 (TRAF6) and forms a trap preventing the mitochondrial recruitment of TRAF6, an essential event for ROS generation within mitochondria. By studying the response of Traf6(+/+) and Traf6(-/-)mouse embryonic fibroblasts to S. typhimurium infection, we found that TRAF6 promoted apoptosis by increasing ROS accumulation, which led to increased Bax/Bcl-2 ratio, Bax recruitment to mitochondrial membrane, and release of Cyt c into the cytoplasm. These findings show that SopB suppresses host cell apoptosis by binding to TRAF6 and preventing mitochondrial ROS generation.


Subject(s)
Apoptosis , Bacterial Proteins/metabolism , Epithelial Cells/microbiology , Reactive Oxygen Species/metabolism , Salmonella Infections/metabolism , Salmonella typhimurium/physiology , TNF Receptor-Associated Factor 6/metabolism , Animals , Cell Line , Epithelial Cells/metabolism , Fibroblasts/metabolism , Fibroblasts/microbiology , HEK293 Cells , Host-Pathogen Interactions , Humans , Mice , Mitochondria/metabolism , Mitochondria/microbiology , Salmonella Infections/microbiology
6.
Chem Asian J ; 18(1): e202201097, 2023 Jan 03.
Article in English | MEDLINE | ID: mdl-36424185

ABSTRACT

A series of ester-ether copolymers were obtained via the reaction between α,ω-dihydroxyl poly(ϵ-caprolactone) (PCL) and ethylene oxide (EO) or monosubstituted epoxides catalyzed by strong phosphazene bases. The two types of monomeric units were distributed in highly random manners due to the concurrence of epoxide ring-opening and fast transesterification reactions. The substituent of epoxide showed an interesting bidirectional effect on the enzymatic degradability of the copolymer. Compared with PCL, copolymers derived from EO exhibited enhanced hydrophilicity and decreased crystallinity which then resulted in higher degradability. For the copolymers derived from propylene oxide and 1,2-butylene oxide, the hydrophobic alkyl pendant groups also allowed lower crystallinity of the copolymers thus higher degradation rates. However, further enlarging the pendant groups by using styrene oxide or 2-ethylhexyl glycidyl ether caused a decrease in the degradation rate, which might be ascribed to the higher bulkiness hindering the contact of ester groups with lipase.


Subject(s)
Esters , Polymers , Polymers/chemistry , Polyesters/chemistry , Epoxy Compounds
7.
Front Med (Lausanne) ; 9: 837414, 2022.
Article in English | MEDLINE | ID: mdl-35712088

ABSTRACT

Elevation of plasma creatinine after surgery is associated with postoperative morbidity and mortality. We studied whether lengthy surgery might induce renal conservation of water strong enough to exceed the renal capacity to excrete creatinine. Colorectal cancer surgery was performed via laparoscopy in 126 patients. Blood and urine were sampled before surgery, in the postoperative care unit, and 1 day after surgery. The Fluid Retention Index (FRI), which is a composite index of renal water conservation, was calculated. The mean FRI before surgery was 2.4, indicating that patients were well-hydrated. The FRI increased to 2.8 after surgery, and further to 3.5 on the first postoperative day. Plasma creatinine increased in 66 (52%) of the patients while plasma proteins were diluted by 15%. Patients with urinary creatinine > 8.5 mmol/L before surgery were more likely to later show elevation of plasma creatinine (68 vs. 46%, P < 0.04). The final FRI was higher in those with perioperative elevation of plasma creatinine (median 3.7 vs. 3.4; P < 0.01) and a similar difference was found for the final urinary creatinine concentration (8.5 vs. 7.2 mmol/L; P < 0.01). The gastrointestinal recovery time was prolonged when >2 L of Ringer's had been infused during the surgery. We conclude that colorectal surgery initiated a process of renal water conservation that extended into the postoperative period. The water conservation was more intense and the urinary concentration of creatinine was higher in those who had a perioperative rise in plasma creatinine.

8.
Polymers (Basel) ; 14(11)2022 Jun 01.
Article in English | MEDLINE | ID: mdl-35683935

ABSTRACT

Liquid metal (LM)-polymer composites that combine the thermal and electrical conductivity of LMs with the shape-morphing capability of polymers are attracting a great deal of attention in the fields of reconfigurable electronics and soft robotics. However, investigation of the synergetic effect between the shape-changing properties of LMs and polymer matrices is lacking. Herein, a self-healable and recyclable dual-shape memory composite, comprising an LM (gallium) and a Diels-Alder (DA) crosslinked crystalline polyurethane (PU) elastomer, is reported. The composite exhibits a bilayer structure and achieves excellent shape programming abilities, due to the phase transitions of the LM and the crystalline PU elastomers. To demonstrate these shape-morphing abilities, a heat-triggered soft gripper, which can grasp and release objects according to the environmental temperature, is designed and built. Similarly, combining the electrical conductivity and the dual-shape memory effect of the composite, a light-controlled reconfigurable switch for a circuit is produced. In addition, due to the reversible nature of DA bonds, the composite is self-healable and recyclable. Both the LM and PU elastomer are recyclable, demonstrating the extremely high recycling efficiency (up to 96.7%) of the LM, as well as similar mechanical properties between the reprocessed elastomers and the pristine ones.

9.
ACS Appl Mater Interfaces ; 14(37): 42744-42756, 2022 Sep 21.
Article in English | MEDLINE | ID: mdl-36068651

ABSTRACT

Adhesion and spreading of liquid metals (LMs) on substrates are essential steps for the generation of flexible electronics and thermal management devices. However, the controlled deposition is limited by the high surface tension and peculiar wetting and adhesion behavior of LMs. Herein, we introduce gelatin-regulated LM droplet deposition and sintering (GLMDDS), for the upscalable production of conformally adhesive, solidlike, yet transient LM thin films and patterns on diverse substrates. This method involves four steps: homogeneous deposition of LM microdroplets, gelation of the LM-gelatin solution, toughening of the gelatin hydrogel by solvent displacement, and peeling-induced sintering of LM microdroplets. The LM thin film exhibits a three-layer structure, comprising an LM microdroplet-embedded tough organohydrogel adhesion layer, a continuous LM layer, and an oxide skin. The composite exhibits high stretchability and mechanical robustness, conformal adhesion to various substrates, high conductivity (4.35 × 105 S·m-1), and transience (86% LM recycled). Large-scale deposition (i.e., 5.6 dm2) and the potential for patterns on diverse substrates demonstrate its upscalability and broad suitability. Finally, the LM thin films and patterns are applied for flexible and wearable devices, i.e., pressure sensors, heaters, human motion tracking devices, and thermal management devices, illustrating the broad applicability of this strategy.

10.
Front Psychiatry ; 13: 853795, 2022.
Article in English | MEDLINE | ID: mdl-35280171

ABSTRACT

Objective: Posttraumatic stress disorder (PTSD) is a frequent and disabling consequence of traumatic events. A previous study found that early use of propofol was a potential risk factor for PTSD. This prospective study aimed to investigate the effect of propofol and sevoflurane on PTSD after emergency surgery in trauma patients. Methods: A total of 300 trauma patients undergoing emergency surgery were randomly divided into two groups and anesthetized with propofol and/or sevoflurane. Perioperative clinical data were collected. The incidence of PTSD was evaluated with the Clinician-Administered PTSD Scale for DSM-5 (CAPS-5) in the two groups 1 month after the operation. The relevance of the injury time and CAPS-5 scores was assessed by Spearman correlation analysis. Logistic regression analysis was used to analyze the risk factors for PTSD. Results: The incidence of PTSD in the propofol group was higher than that in the sevoflurane group 1 month postoperatively (23.2 vs. 12.2%, P = 0.014). The injury time was negatively correlated with the CAPS-5 score in the propofol group (r = -0.226, P < 0.001). In the logistic regression analysis, the utilization of propofol was an independent risk factor for PTSD (P = 0.017). Conclusion: Early use of propofol general anesthesia in emergency surgery for trauma patients may increase the risk of PTSD. Clinical Trial Registration: www.chictr.org.cn, identifier: ChiCTR2100050202.

11.
Front Med (Lausanne) ; 8: 706844, 2021.
Article in English | MEDLINE | ID: mdl-35111766

ABSTRACT

OBJECTIVE: To compare the efficacy of intravenous (IV) lidocaine with standard analgesics (NSAIDS, opioids) for pain control due to any cause in the emergency department. METHODS: The electronic databases of PubMed, Embase, ScienceDirect, CENTRAL, and Google Scholar were explored from 1st January 2000 to 30th March 2021 and randomized controlled trials (RCTs) comparing IV lidocaine with a control group of standard analgesics were included. RESULTS: Twelve RCTs including 1,351 patients were included. The cause of pain included abdominal pain, renal or biliary colic, traumatic pain, radicular low back pain, critical limb ischemia, migraine, tension-type headache, and pain of unknown origin. On pooled analysis, we found no statistically significant difference in pain scores between IV lidocaine and control group at 15 min (MD: -0.24 95% CI: -1.08, 0.61 I 2 = 81% p = 0.59), 30 min (MD: -0.24 95% CI: -1.03, 0.55 I 2 = 86% p = 0.55), 45 min (MD: 0.31 95% CI: -0.66, 1.29 I 2 = 66% p = 0.53), and 60 min (MD: 0.59 95% CI: -0.26, 1.44 I 2 = 75% p = 0.18). There was no statistically significant difference in the need for rescue analgesics between the two groups (OR: 1.45 95% CI: 0.82, 2.56 I 2 = 41% p = 0.20), but on subgroup analysis, the need for rescue analgesics was significantly higher with IV lidocaine in studies on abdominal pain but not for musculoskeletal pain. On meta-analysis, there was no statistically significant difference in the incidence of side-effects between the two study groups (OR: 1.09 95% CI: 0.59, 2.02 I 2 = 48% p = 0.78). CONCLUSION: IV lidocaine can be considered as an alternative analgesic for pain control in the ED. However, its efficacy may not be higher than standard analgesics. Further RCTs with a large sample size are needed to corroborate the current conclusions.

12.
J Biomed Nanotechnol ; 15(11): 2262-2270, 2019 Nov 01.
Article in English | MEDLINE | ID: mdl-31847940

ABSTRACT

Gold nano rods (GNRs) have showed cytotoxicity to cancer cells. At the same time, it shows little effects on non-tumor cells. Between GNRs and sub-cellular organelles, the understanding of interaction plays a very important role to determine the intracellular mechanisms. The purpose of what we done is to explain the effects of the surface properties of GNRs on specific cancer cell death. Three GNR samples with different aspect ratios were finely prepared by the seed-mediated growth method. Then the intracellular transport and the in vitro/vivo mechanisms of cancer cell death were studied by transmission electron microscopy (TEM), confocal laser scanning microscopy (CLSM), laser light scattering, and flow cytometry (FCM). It was found that GNRs700 exhibited the largest photothermal conversion efficiency. However, the GNR660 with or without light stimulation exhibited the highest cytotoxicity against cancer cells, which was contradict to the general knowledge. Detailed intracellular investigations showed that the lysosome was the key sub-organelle affecting the GNR function. Further experiments revealed that cytotoxicity was strongly affected by the GNR's surface potential. This potential was actually related to the density of surface cationic molecules, which further regulated lysosomal membrane penetration. The results obtained herein indicated that the physicochemical properties of the surface potential mediated the specific toxicity of GNRs against tumours.


Subject(s)
Gold , Nanotubes , Cell Line, Tumor , Humans , Lasers , Surface Properties
13.
Oncotarget ; 8(68): 113163-113173, 2017 Dec 22.
Article in English | MEDLINE | ID: mdl-29348895

ABSTRACT

It was recently reported that increased SOX9 expression drives tumor growth and promotes cancer invasion during human tumorigenicity and metastasis. However, the prognostic value of SOX9 for the survival of patients with solid tumors remains controversial. The present meta-analysis was thus performed to highlight the link between dysregulated SOX9 expression and prognosis in cancer patients. A systematic literature search was conducted using the electronic databases PubMed, Web of Science and Embase to identify eligible studies. A random-effects meta-analytical model was employed to correlate SOX9 expression with overall survival (OS), disease-free survival (DFS) and clinicopathological features. In total, 17 studies with 3307 patients were eligible for the final analysis. Combined hazard ratios (HRs) and 95% confidence intervals (CIs) suggested that high SOX9 expression has an unfavourable impact on OS (HR = 1.66, 95% CI 1.36-2.02, P < 0.001) and DFS (HR = 3.54, 95% CI 2.29-5.47, P = 0.008) in multivariate analysis. Additionally, the pooled odds ratios (ORs) indicated that SOX9 over-expression is associated with large tumor size, lymph node metastasis, distant metastasis and a higher clinical stage. Overall, these results indicated that SOX9 over-expression in patients with solid tumors might be related to poor prognosis and could serve as a potential predictive marker of poor clinicopathological prognosis factor.

14.
ACS Macro Lett ; 5(1): 40-44, 2016 Jan 19.
Article in English | MEDLINE | ID: mdl-35668601

ABSTRACT

Inter- and intrachain transesterification, normally regarded as a detrimental side reaction for the synthesis of polyesters, is utilized herein to formulate a novel strategy for the modification of polyesters. Addition of an organic superbase into the mixture of hydroxyl-terminated poly(ε-caprolactone) and an epoxide, for example, propylene oxide or 1,2-butylene oxide, triggers concurrent nucleophilic ring-opening of the epoxide and transesterification reaction. The synergetic effect enables convenient and efficient transformation of the polyester into poly(ester-ether) random copolymers and thus advances the preparation of functional degradable polymeric materials taking advantage of the variety of commercial and laboratory-made polyesters and epoxides.

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