ABSTRACT
The interaction between catalyst and support plays an important role in electrocatalytic hydrogen evolution (HER), which may explain the improvement in performance by phase transition or structural remodeling. However, the intrinsic behavior of these catalysts (dynamic evolution of the interface under bias, structural/morphological transformation, stability) has not been clearly monitored, while the operando technology does well in capturing the dynamic changes in the reaction process in real time to determine the actual active site. In this paper, nitrogen-doped molybdenum atom-clusters on Ti3 C2 TX (MoACs /N-Ti3 C2 TX ) is used as a model catalyst to reveal the dynamic evolution of MoAcs on Ti3 C2 TX during the HER process. Operando X-ray absorption structure (XAS) theoretical calculation and in situ Raman spectroscopy showed that the Mo cluster structure evolves to a 6-coordinated monatomic Mo structure under working conditions, exposing more active sites and thus improving the catalytic performance. It shows excellent HER performance comparable to that of commercial Pt/C, including an overpotential of 60 mV at 10 mA cm-2 , a small Tafel slope (56 mV dec-1 ), and high activity and durability. This study provides a unique perspective for investigating the evolution of species, interfacial migration mechanisms, and sources of activity-enhancing compounds in the process of electroreduction.
ABSTRACT
Whether single-incision laparoscopic totally extraperitoneal (SIL-TEP) inguinal hernia repair is similar or superior to multi-trocar laparoscopic totally extraperitoneal (MTL-TEP) inguinal hernia repair is controversial. We conducted this meta-analysis to compare the safety, efficacy and cosmetic effect of the two surgical methods. We systematically searched the Cochrane Library, Embase database and PubMed database for published studies on SIL-TEP and MTL-TEP inguinal hernia repair. The studies were screened and evaluated for quality according to the inclusion and exclusion criteria, and RevMan 5.3 software was used for meta-analysis. Twenty studies were included, including 7 randomized controlled studies and 13 nonrandomized controlled studies. Meta-analysis revealed no significant difference between SIL-TEP and MTL-TEP inguinal hernia repair in terms of unilateral operation time (P = 0.12), bilateral operation time (P = 0.72), pain score on the first day after operation (P = 0.61], chronic pain rate (P = 0.61), total complication rate (P = 0.26), hospital stay (P = 0.72), and recurrence rate (P = 0.83), but the cosmetic effect score (P = 0.002) was higher in the former. These findings demonstrate that SIL-TEP inguinal hernia repair is safe, reliable and feasible. In addition, it can result in a better cosmetic effect of the incision than MTL-TEP inguinal hernia repair. SIL-TEP inguinal hernia repair should be considered for patients with stricter cosmetic requirements.Clinical trial registration: INPLASY2022110085.
Subject(s)
Hernia, Inguinal , Laparoscopy , Humans , Hernia, Inguinal/surgery , Herniorrhaphy/methods , Laparoscopy/methods , Length of Stay , Surgical Instruments , Treatment OutcomeABSTRACT
The real structure and in situ evolution of catalysts under working conditions are of paramount importance, especially for bifunctional electrocatalysis. Here, we report asymmetric structural evolution and dynamic hydrogen-bonding promotion mechanism of an atomically dispersed electrocatalyst. Pyrolysis of Co/Ni-doped MAF-4/ZIF-8 yielded nitrogen-doped porous carbons functionalized by atomically dispersed Co-Ni dual-metal sites with an unprecedented N8V4 structure, which can serve as an efficient bifunctional electrocatalyst for overall water splitting. More importantly, the electrocatalyst showed remarkable activation behavior due to the in situ oxidation of the carbon substrate to form C-OH groups. Density functional theory calculations suggested that the flexible C-OH groups can form reversible hydrogen bonds with the oxygen evolution reaction intermediates, giving a bridge between elementary reactions to break the conventional scaling relationship.
ABSTRACT
In this study, 9-anthracenemethyl methacrylate (AMMA) and styrene (St) as monomers and benzoyl peroxide as an initiator were used to synthesize P(St-co-AMMA), a macromolecule tracer with a fluorescence effect, via free radical copolymerization. A fluorescent online detection device was built on the basis of the principle of fluorescence online detection by using the single-screw extrusion platform of a torque rheometer to explore the effect of the amount of macromolecular tracer and screw speed on the residence time distribution of polystyrene in single-screw extrusion. Fourier transform infrared spectroscopy, 1H-NMR, thermal stability, fluorescence properties, and rheological properties show that the resulting product P(St-co-AMMA) has a degree of thermal stability, fluorescence, and rheological properties similar to polystyrene, so this product can be used to characterize the residence time distribution during single-screw extrusion. The amount of macromolecular tracer P(St-co-AMMA) does not affect the residence time distribution of polystyrene during single-screw extrusion processing, meanwhile, the minimum residence time decreases and the residence time distribution becomes narrow as the screw speed increases, that is, the axial mixing capacity of the single-screw extruder decreases as the screw speed increases.
ABSTRACT
The blending of aliphatic polyolefins and aromatic poly(ethylene terephthalate) (PET) based on different intrinsic viscosities (IV) was conducted in a torque rheometer. The comparison of blend components in terms of low density polythene (LDPE) and polypropylene (PP) in blending with PET was investigated, and the effects of the IV and proportion of PET on polymer blends are discussed in detail. Polymer blends with or without compatibilizer were examined by using a differential scanning calorimeter, thermogravimetric analyzer, rotary rheometer, field-emission scanning electron microscopy and a universal testing machine. It was found that the blending led to an increase in processability and a decrease in thermal stability for blends. The morphological analysis revealed that the incompatibility of blends was aggravated by a higher IV of PET, while this situation could be improved by the addition of compatibilizer. Results showed that there was an opposite effect for the tensile strength and the elongation at break of the polymer blend in the presence of a compatibilizer, wherein the influence of IV of PET was complicated.
ABSTRACT
Accumulative evidences have underpinned the nature candidates from Chinese medicine (CM), particularly CM served as blood activating and stasis resolving (BASR, Huoxue Huayu in Chinese) by targeting tumor-associated angiogenesis. However, recent experiment research on the therapeutic angiogenesis by BASR-CM attracts wide attention and discussion. This opinion review focused on the underlying link between two indications and anticipated that (1) BASR-CM might emphasize on a balanced multi-cytokines network interaction; (2) BASR-CM might address on the nature of diseases prior to differently affecting physiological and pathological angiogenesis; (3) BASR-CM might mainly act on perivascular cells, either promotes arteriogenesis by increasing arteriogenic factors in ischemic diseases, or simultaneously keep a quiescent vasculature to impede angiogenesis in tumor context.
Subject(s)
Drugs, Chinese Herbal/therapeutic use , Neovascularization, Pathologic/blood , Neovascularization, Pathologic/drug therapy , Angiogenesis Inhibitors/chemistry , Angiogenesis Inhibitors/therapeutic use , Animals , Antineoplastic Agents/therapeutic use , Drugs, Chinese Herbal/chemistry , Humans , Models, BiologicalABSTRACT
A new phenolic glycoside derivative, saproglucoside (1), along with five known phenolic glycoside derivatives (2-6) were isolated from the stems of Saprosma merrillii. The structure of the new compound 1 was determined by 1D and 2D NMR as well as by HRESIMS and hydrolysis. The inhibitory activities of all compounds against seven pathogenic bacteria and two cancer cell lines were evaluated.
Subject(s)
Glucosides/isolation & purification , Phenols/isolation & purification , Rubiaceae/chemistry , Anti-Bacterial Agents/pharmacology , Antineoplastic Agents, Phytogenic/pharmacology , Cell Line, Tumor , Glucosides/chemistry , Glucosides/pharmacology , Humans , Magnetic Resonance Spectroscopy , Phenols/chemistry , Phenols/pharmacologyABSTRACT
To investigate the antiemetic effect of the active extract (ginger ether extract, GEE) and its bioactive compounds in ginger, the pica vomiting model in rats and the gastric emptying model in mice were used to observe the antiemetic effect of GEE in cisplatin-induced pica and gastric emptying, and the main components in GEE were detected by RP-HPLC; in vitro, the antagonist effect of GEE and the four components in it were explored by the contraction of guinea-pig ileum induced by SR57227A and carbachol. The results showed that the amount of Kaolin ingested by rats were declined significantly in all the three groups of GEE (25,50,100 mgâ¢kg⻹) (P<0.01), while cisplatin-induced gastric emptying in mice was also suppressed in all the three groups (P<0.01), and 6-gingerol, 8-gingerol,10-gingerol and 6-shogaol were found mainly in GEE by RP-HPLC; the maximum contraction of isolated guinea-pig ileum could be reduced by addition of GEE (2.3, 4.6, 11.5 mgâ¢L⻹), 6-gingerol,8-gingerol,10-gingerol or 6-shogaol (1, 2, 5 µmolâ¢L⻹) when the concentration of SR5727A was 1×10â»5 molâ¢L⻹ and that of carbachol was 1×10â»4 molâ¢L⻹ (P<0.05, P<0.01). In conclusion, 5-HT3 and M3 receptors could be antagonized by GEE and its bioactive compounds 6-gingerol, 8-gingerol, 10-gingerol and 6-shogaol, which may be correlated with the antiemetic mechanism of ginger maybe related to it.
Subject(s)
Antiemetics/administration & dosage , Plant Extracts/administration & dosage , Vomiting/drug therapy , Zingiber officinale/chemistry , Animals , Antiemetics/chemistry , Catechols/administration & dosage , Catechols/chemistry , Fatty Alcohols/administration & dosage , Fatty Alcohols/chemistry , Guinea Pigs , Male , Mice , Mice, Inbred ICR , Plant Extracts/chemistry , Rats , Rats, Sprague-DawleyABSTRACT
BACKGROUND: Acupuncture treatment has been increasingly used to treat chronic liver diseases. We previously reported that acupuncture combined with curcumin, a natural antifibrotic compound, could remarkably attenuate liver fibrosis in chemically intoxicated rats, but the underlying molecular mechanisms are poorly understood. The present study was aimed at investigating the effects of acupuncture combined with curcumin on platelet-derived growth factor (PDGF) signalling and extracellular matrix (ECM) regulation in the fibrotic liver. METHODS: A total of 60 Sprague-Dawley male rats were randomly divided into control, model, sham, acupuncture, curcumin and combination treatment groups. During the establishment of fibrosis using carbon tetrachloride (CCl(4)), acupuncture at LR3, LR14, BL18 and ST36 and/or curcumin treatment by mouth were performed simultaneously. After treatment, serum PDGF levels were measured. Protein and mRNA expression of key effectors in PDGF pathway and fibrinolysis in the liver was determined. RESULTS: Acupuncture combined with curcumin potently reduced serum PDGF levels and selectively disrupted the PDGF-ßR/extracellular signal-regulated kinase (ERK) cascade. Combination treatment also significantly repressed expression of connective tissue growth factor and upregulated expression of matrix metalloproteinase-9, promoting fibrinolysis in the fibrotic liver. CONCLUSIONS: The beneficial effects of acupuncture and its combination with curcumin could be attributed to the disruption of PDGF-ßR/ERK pathway and stimulated ECM degradation in the fibrotic liver. Acupuncture treatment significantly enhanced curcumin effects at the molecular level. These findings may provide molecular insights into the potential of acupuncture combined with curcumin for prevention of hepatic fibrosis.
Subject(s)
Acupuncture Therapy , Curcumin/administration & dosage , Extracellular Matrix/metabolism , Extracellular Signal-Regulated MAP Kinases/metabolism , Liver Cirrhosis/therapy , Receptor, Platelet-Derived Growth Factor beta/metabolism , Animals , Carbon Tetrachloride/adverse effects , Combined Modality Therapy , Extracellular Signal-Regulated MAP Kinases/genetics , Humans , Liver Cirrhosis/drug therapy , Liver Cirrhosis/genetics , Liver Cirrhosis/metabolism , Male , Rats , Rats, Sprague-Dawley , Receptor, Platelet-Derived Growth Factor beta/genetics , Signal TransductionABSTRACT
OBJECTIVE: To observe the effect of acupuncture stimulation of "Taichong" (LR 3), "Qimen" (LR 14), etc. on hepatic platelet-derived growth factor (PDGF) signal pathway activity at the protein and mRNA levels in hepatic fibrosis rats. METHODS: Forty-six SD rats were randomly divided into control (10 rats), model (12 rats), acupuncture (12 rats) and non-acupoint (12 rats) groups. Hepatic fibrosis model was established by intraperitoneal injection of mixture solution of 50% CCl4 and olive oil [1:1, 3 times on the 1st week (W), twice/W thereafter for 5 more weeks]. During modeling, acupuncture stimulation of "Taichong" (LR 3), "Qimen" (LR 14), "Ganshu" (BL 18) and "Zusanli" (ST 36) was conducted simultaneously. At the end of the experiments, all the rats were sacrificed for collecting their liver and blood samples, followed by separation of the hepatic stellate cells (HSCs). ELISA, Western blot and Real-time quantitative PCR techniques were used to detect the content of serum PDGF and expression levels of PDGF-beta receptor (PDGF-beta R), extracellular signal-regulated kinase (ERK1/2), c-jun N-terminal kinase (JNK) and P 38 genes and proteins of HSCs, respectively. RESULTS: Compared to the control group, serum PDGF content, and expression levels of PDGF-beta R mRNA and protein, ERK mRNA and protein and P 38 protein of HSCs in the model group were upregulated significantly (P < 0.01, P < 0.05). In comparison with the model group, serum PDGF content, and the expression levels of PDGF-beta R mRNA and protein, ERK mRNA and protein of HSCs in the acupuncture group were down-regulated apparently (P < 0.05, P < 0.01). No significant differences were found between the acupuncture and non-acupoint groups in serum PDGF content and between the model group and non-acupoint group in the expression levels of PDGF-beta R mRNA and protein, ERK mRNA and protein, JNK protein and P 38 protein of HSCs, as well as between the model group and acupuncture group in the expression levels of JNK protein and P 38 protein of HSCs (P > 0.05). CONCLUSION: Acupuncture intervention can effectively down-regulate serum PDGF content, and expression levels of PDGF-beta R mRNA and protein, ERK mRNA and protein of HSCs in liver fibrosis rats, which may contribute to its effect in improving liver fibrosis through down-regulating PDGF signal pathway activity.
Subject(s)
Acupuncture Therapy , Carbon Tetrachloride/adverse effects , Liver Cirrhosis/metabolism , Liver Cirrhosis/therapy , Platelet-Derived Growth Factor/metabolism , Signal Transduction , Animals , Humans , JNK Mitogen-Activated Protein Kinases/genetics , JNK Mitogen-Activated Protein Kinases/metabolism , Liver Cirrhosis/chemically induced , Liver Cirrhosis/genetics , Mitogen-Activated Protein Kinases/genetics , Mitogen-Activated Protein Kinases/metabolism , Platelet-Derived Growth Factor/genetics , Rats , Rats, Sprague-Dawley , Receptor, Platelet-Derived Growth Factor beta/genetics , Receptor, Platelet-Derived Growth Factor beta/metabolismABSTRACT
BACKGROUND: Increasingly, studies demonstrate the effectiveness of acupuncture therapy against liver fibrosis. Curcumin is a natural product with antifibrotic effects, but has poor pharmacokinetic profiles. This study aimed to evaluate whether acupuncture combined with curcumin could more potently attenuate liver fibrosis in chemical intoxicated rats. METHODS: 60 Sprague-Dawley male rats were randomly divided into control, model, sham, acupuncture, curcumin and combination therapy groups. During the establishment of fibrosis using carbon tetrachloride (CCl(4)), acupuncture at LR3, LR14, BL18 and ST36 and/or curcumin treatment by mouth were performed simultaneously. After treatment, pathological indexes and histology for hepatic injury and fibrogenesis were detected. The expression of extracellular matrix (ECM) components was also determined. RESULTS: Acupuncture combined with curcumin potently protected the liver from CCl(4)-induced injury and fibrogenesis, as indicated by reduced levels of serum aspartate aminotransferase, alanine aminotransferase, alkaline phosphatase, hyaluronic acid, laminin and procollagen III. Combined use also led to significant liver histological improvements. Furthermore, combined use effectively inhibited ECM expression such as α-smooth muscle actin, fibronectin and α1(1) collagen. CONCLUSIONS: Acupuncture treatment could significantly enhance the antifibrotic efficacy of curcumin on CCl(4)-induced hepatic fibrosis in rats in vivo, suggesting that a combination of acupuncture with curcumin may be exploited for the prevention of hepatic fibrosis.