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1.
Science ; 384(6697): 757-762, 2024 May 17.
Artigo em Inglês | MEDLINE | ID: mdl-38753787

RESUMO

Electronic band convergence can have a beneficial impact on thermoelectric performance, but finding the right band-converged compositions is still time-consuming. We propose a method for designing a series of compositions with simultaneous band convergence in the high-entropy YbxCa1-xMgyZn2-ySb2 material by zeroing the weighted sum of crystal-field splitting energies of the parent compounds. We found that so-designed compositions have both larger power factors and lower thermal conductivities and that one of these compositions exhibits a large thermoelectric figure of merit value in comparison with to other p-type Zintls. Our material shows high stability both thermally and temporally. We then assembled an all-Zintl single-stage module, nontoxic and free of tellurium, that demonstrates an exceptional heat-to-electricity conversion efficiency exceeding 10% at a temperature difference of 475 kelvin.

2.
Science ; 382(6673): 921-928, 2023 Nov 24.
Artigo em Inglês | MEDLINE | ID: mdl-37995213

RESUMO

Thermoelectric interface materials (TEiMs) are essential to the development of thermoelectric generators. Common TEiMs use pure metals or binary alloys but have performance stability issues. Conventional selection of TEiMs generally relies on trial-and-error experimentation. We developed a TEiM screening strategy that is based on phase diagram predictions by density functional theory calculations. By combining the phase diagram with electrical resistivity and melting points of potential reaction products, we discovered that the semimetal MgCuSb is a reliable TEiM for high-performance MgAgSb. The MgCuSb/MgAgSb junction exhibits low interfacial contact resistivity (ρc <1 microhm square centimeter) even after annealing at 553 kelvin for 16 days. The fabricated two-pair MgAgSb/Mg3.2Bi1.5Sb0.5 module demonstrated a high conversion efficiency of 9.25% under a 300 kelvin temperature gradient. We performed an international round-robin testing of module performance to confirm the measurement reliability. The strategy can be applied to other thermoelectric materials, filling a vital gap in the development of thermoelectric modules.

3.
Nat Commun ; 14(1): 4722, 2023 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-37543679

RESUMO

Studies of vacancy-mediated anomalous transport properties have flourished in diverse fields since these properties endow solid materials with fascinating photoelectric, ferroelectric, and spin-electric behaviors. Although phononic and electronic transport underpin the physical origin of thermoelectrics, vacancy has only played a stereotyped role as a scattering center. Here we reveal the multifunctionality of vacancy in tailoring the transport properties of an emerging thermoelectric material, defective n-type ZrNiBi. The phonon kinetic process is mediated in both propagating velocity and relaxation time: vacancy-induced local soft bonds lower the phonon velocity while acoustic-optical phonon coupling, anisotropic vibrations, and point-defect scattering induced by vacancy shorten the relaxation time. Consequently, defective ZrNiBi exhibits the lowest lattice thermal conductivity among the half-Heusler family. In addition, a vacancy-induced flat band features prominently in its electronic band structure, which is not only desirable for electron-sufficient thermoelectric materials but also interesting for driving other novel physical phenomena. Finally, better thermoelectric performance is established in a ZrNiBi-based compound. Our findings not only demonstrate a promising thermoelectric material but also promote the fascinating vacancy-mediated anomalous transport properties for multidisciplinary explorations.

4.
Adv Mater ; 35(44): e2306097, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37607336

RESUMO

Developing non-precious catalysts with long-term catalytic durability and structural stability under industrial conditions is the key to practical alkaline anion exchange membrane (AEM) water electrolysis. Here, an energy-saving approach is proposed to synthesize defect-rich iron nickel oxyhydroxide for stability and efficiency toward the oxygen evolution reaction. Benefiting from in situ cation exchange, the nanosheet-nanoflake-structured catalyst is homogeneously embedded in, and tightly bonded to, its substrate, making it ultrastable at high current densities. Experimental and theoretical calculation results reveal that the introduction of Ni in FeOOH reduces the activation energy barrier for the catalytic reaction and that the purposely created oxygen defects not only ensure the exposure of active sites and maximize the effective catalyst surface but also modulate the local coordination environment and chemisorption properties of both Fe and Ni sites, thus lowering the energy barrier from *O to *OOH. Consequently, the optimized d-(Fe,Ni)OOH catalyst exhibits outstanding catalytic activity with long-term durability under both laboratory and industrial conditions. The large-area d-(Fe,Ni)OOH||NiMoN pair requires 1.795 V to reach a current density of 500 mA cm-2 at an absolute current of 12.5 A in an AEM electrolyzer for overall water electrolysis, showing great potential for industrial water electrolysis.

5.
Nanomicro Lett ; 15(1): 157, 2023 Jun 19.
Artigo em Inglês | MEDLINE | ID: mdl-37336833

RESUMO

NiMo-based nanostructures are among the most active hydrogen evolution reaction (HER) catalysts under an alkaline environment due to their strong water dissociation ability. However, these nanostructures are vulnerable to the destructive effects of H2 production, especially at industry-standard current densities. Therefore, developing a strategy to improve their mechanical strength while maintaining or even further increasing the activity of these nanocatalysts is of great interest to both the research and industrial communities. Here, a hierarchical interconnected NiMoN (HW-NiMoN-2h) with a nanorod-nanowire morphology was synthesized based on a rational combination of hydrothermal and water bath processes. HW-NiMoN-2h is found to exhibit excellent HER activity due to the accomodation of abundant active sites on its hierarchical morphology, in which nanowires connect free-standing nanorods, concurrently strengthening its structural stability to withstand H2 production at 1 A cm-2. Seawater is an attractive feedstock for water electrolysis since H2 generation and water desalination can be addressed simultaneously in a single process. The HER performance of HW-NiMoN-2h in alkaline seawater suggests that the presence of Na+ ions interferes with the reation kinetics, thus lowering its activity slightly. However, benefiting from its hierarchical and interconnected characteristics, HW-NiMoN-2h is found to deliver outstanding HER activity of 1 A cm-2 at 130 mV overpotential and to exhibit excellent stability at 1 A cm-2 over 70 h in 1 M KOH seawater.

6.
Adv Mater ; 34(21): e2201774, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-35363922

RESUMO

Achieving efficient and durable nonprecious hydrogen evolution reaction (HER) catalysts for scaling up alkaline water/seawater electrolysis is desirable but remains a significant challenge. Here, a heterogeneous Ni-MoN catalyst consisting of Ni and MoN nanoparticles on amorphous MoN nanorods that can sustain large-current-density HER with outstanding performance is demonstrated. The hierarchical nanorod-nanoparticle structure, along with a large surface area and multidimensional boundaries/defects endows the catalyst with abundant active sites. The hydrophilic surface helps to achieve accelerated gas-release capabilities and is effective in preventing catalyst degradation during water electrolysis. Theoretical calculations further prove that the combination of Ni and MoN effectively modulates the electron redistribution at their interface and promotes the sluggish water-dissociation kinetics at the Mo sites. Consequently, this Ni-MoN catalyst requires low overpotentials of 61 and 136 mV to drive current densities of 100 and 1000 mA cm-2 , respectively, in 1 m KOH and remains stable during operation for 200 h at a constant current density of 100 or 500 mA cm-2 . This good HER catalyst also works well in alkaline seawater electrolyte and shows outstanding performance toward overall seawater electrolysis with ultralow cell voltages.

7.
Gland Surg ; 10(8): 2528-2534, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34527564

RESUMO

BACKGROUND: In the process of laparoscopic splenic vessels and spleen preservation distal pancreatectomy (LsvSPDP), because the splenic blood vessels have many small branches, how to safely separate the splenic blood vessels from the pancreas has always been the focus and difficulty of this operation. Many cases were switched to laparotomy, or the Warshaw method due to the inability to control bleeding during the separation of the splenic blood vessels. Therefore, we tried to use the selective splenic vascular control method when separating the splenic blood vessels to observe its effect on the conditions of the surgical patients during and after the operation. METHODS: We retrospectively collected 35 cases of LsvSPDP conducted in our center from September 2015 to December 2020, including 5 males and 30 females. Considering the influence of the surgical learning curve, the cases were divided into three groups. Finally, through statistics of its intraoperative and postoperative conditions, the effectiveness of selective splenic vascular control method can be judged. RESULTS: Patients in Group 2 and 3 showed significantly less blood loss (172.5 and 134.44 mL, respectively) compared to patients in Group 1 (541.43 mL; P=0.01). However, the amount of blood loss was not significantly different between Group 2 and 3. CONCLUSIONS: The amount of bleeding was significantly reduced by splenic blood vessel control technology. And it can improve the success rate of spleen preservation, preserve the success rate of splenic blood vessels, and reduce intraoperative bleeding.

8.
Front Oncol ; 11: 666313, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34395245

RESUMO

Pancreatic cancer is known for its notorious fast progression and poor prognosis. Long noncoding RNA (lncRNA) AL161431.1 has been reported to be involved in the pathogenesis of different cancers. In this study, we explored the role of lncRNA AL161431.1 in the development and progression of pancreatic cancer by bioinformatic analysis, in vitro and in vivo experiments in pancreatic cancer BxPC-3 and SW1990 cells, as well as clinical samples. We found that lncRNA AL161431.1 was highly expressed in pancreatic cancer cells and tissues. Knock down of lncRNA AL161431.1 led to increased cancer cell death and cell cycle arrest. Xenograft growth of SW1990 cells with stable knockdown of lncRNA AL161431.1 in mice was significantly slower than that of SW1990 cells with scrambled control shRNA. Finally, we showed the involvement of lncRNA AL161431.1 in pancreatic cancer was related to its promotion of epithelial mesenchymal transition process.

9.
Gland Surg ; 10(7): 2304-2312, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-34422601

RESUMO

OBJECTIVE: Our purpose is to explain the onset, diagnosis, and treatment of pancreatic tumor-associated pancreatitis (PTP), and inform clinicians about the management of PTP. It is hoped that clinicians can gain some experience and inspiration from this review, so that patients can obtain better treatment results. BACKGROUND: Acute pancreatitis (AP) is an inflammatory disease, and pancreatic tumors are one of the causes of pancreatitis. When pancreatic tumors and pancreatitis exist at the same time, and there is a "connection" between them, this type of pancreatitis is referred to as PTP. The manifestations of PTP can be as follows: (I) AP is the first symptom of pancreatic tumors; (II) pancreatitis is found in patients after pancreatic tumor diagnosis or during pancreatic tumor surgery. Because pancreatic tumors are not one of the most common causes of pancreatitis, PTP has not attracted the attention of researchers and clinicians, and there is no consistent and clear understanding of the diagnosis and treatment of PTP. METHODS: From the online database PubMed (https://pubmed.ncbi.nlm.nih.gov/) and Web of Science (https://webofknowledge.com/), we use specific retrieval strategies to retrieve relevant articles, and we review and discuss them. CONCLUSIONS: What we need to realize is that PTP is different from ordinary AP. It has its own characteristics in terms of diagnosis and treatment, which requires the attention of clinicians. More importantly, future research should design the best diagnosis and treatment algorithms for PTP.

10.
Gland Surg ; 10(7): 2313-2324, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-34422602

RESUMO

OBJECTIVE: Although considerable progress has been made in our understanding of intraductal papillary mucinous neoplasm (IPMN) of the pancreas, there are still some problems to be solved. BACKGROUND: IPMN is one of the most important precancerous lesions of pancreatic cancer, but the relationship between IPMN and pancreatic cancer, and the specific mechanism of the development from IPMN to invasive carcinoma, remain to be explored in depth. With the development of imaging, the detection rate of IPMN has been greatly improved. However, the degree of malignancy of IPMN is difficult to assess, and its classification criteria and surgical treatment strategies are still controversial. Therefore, there is an urgent need for the best treatment plan for IPMN and research that can better predict IPMN recurrence and tumor malignancy. METHODS: From the online database Web of Science (https://webofknowledge.com/) and PubMed (https://pubmed.ncbi.nlm.nih.gov/), we use specific retrieval strategies to retrieve relevant articles based on the topics we discussed, and we review and discuss them. CONCLUSIONS: This paper discusses the related research and progress of IPMN in recent years to improve the understanding of the incidence, diagnosis, treatment, and prognosis of this disease. The follow-up and monitoring of IPMN is particularly important, but the specific strategy also remains controversial.

11.
Gland Surg ; 10(5): 1832-1839, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-34164329

RESUMO

Inflammatory myofibroblastic tumor (IMT) is a rare disease of unknown etiology. It usually occurs in abdominal soft tissues and lung, and is extremely rare in the pancreas. IMT can occur in any part of a person at any age, however, it mostly affects children and young people. Its clinical manifestations are atypical, imaging examinations are not specific, and the differential diagnosis of pancreatic malignancies is difficult, making it easily misdiagnosed. Surgical resection is the preferred method of treatment for IMT. In this case report, we report a rare case of IMT in the neck of the pancreas and reviewed the relevant literature. In our case, the patient was a 57-year-old woman with an IMT in the neck of the pancreas. Abdominal pain was the only clinical symptom, and imaging features were not specific. She underwent surgery to remove the pancreatic mass, and the final diagnosis of IMT was based on histopathology and immunohistochemistry. After 6 months of regular follow-up, the patient had no complications or further incidents. The purpose is to emphasize the difficulty of the preoperative diagnosis of pancreatic IMT and the difficulty of distinguishing it from pancreatic malignancies. It is hoped that clinicians can gain a deeper understanding of pancreatic IMT through this case report.

12.
Ann Transl Med ; 9(10): 877, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-34164511

RESUMO

BACKGROUND: Long non-coding ribonucleic acid (lncRNA) ELFN1 antisense RNA 1 (ELFN1-AS1) is involved in the pathogenesis of many different cancers. But the current research on the relationship between lncRNA ELFN1-AS1 and pancreatic cancer is still blank. METHODS: We investigated the role of lncRNA ELFN1-AS1 in the pathogenesis of pancreatic cancer using bioinformatics, in vitro and in vivo experiments in pancreatic cancer cell lines, and surgically removed clinical samples. RESULTS: Through bio-information analysis and in vitro and in vivo experiments, we found that LncRNA ELFN1-AS1 was highly enriched in pancreatic cancer data sets and highly expressed in pancreatic cancer cell lines and tissues. The knocking down of lncRNA ELFN1-AS1 significantly increased cancer cell death and growth arrest. Xenografts in nude mice showed that the growth of SW1990 cells in the mice group with a stable knock down of lncRNA ELFN1-AS1 was significantly slower than that in the control group. CONCLUSIONS: The experimental results show that the expression of LncRNA ELFN1-AS1 is related to the growth and invasion ability of pancreatic cancer cells. By further studying the function of LncRNA ELFN1-AS1 in pancreatic cancer, LncRNA ELFN1-AS1 was found to be involved in the epithelial-mesenchymal transition process in pancreatic cancer.

13.
Cell Death Dis ; 12(7): 656, 2021 06 28.
Artigo em Inglês | MEDLINE | ID: mdl-34183642

RESUMO

Growing evidence indicates that circular RNAs (circRNAs) are closely involved in tumorigenesis, but the association between circRNAs and pancreatic ductal adenocarcinoma (PDAC) is far from clear. Here, we focused on the functional investigation of circ-0005105, a newly identified circRNA, in PDAC progression. In the present study, we assessed circ-0005105 expression in PDAC tissues and cell lines with quantitative reverse transcription-polymerase chain reaction (qRT-PCR). The biological functions of circ-0005105 in cellular proliferation and invasion were identified through gain- and loss-of-function experiments in vitro and in vivo. The interaction between circ-0005105 and the microRNA (miR)-20a-3p-COL11A1 (collagen type XI alpha 1) axis was examined using luciferase reporter and RNA immunoprecipitation assays. We found that circ-0005105 expression was upregulated in both PDAC tissues and cell lines. Higher circ-0005105 expression correlated positively with the malignant clinical phenotype and poor prognosis of patients with PDAC. Gain- and loss-of-function analysis showed that circ-0005105 facilitated both in vitro and in vivo cellular proliferation and invasion. Mechanistically, circ-000510 served as a competing endogenous RNA (ceRNA) of miR-20a-3p and indirectly modulated COL11A1 expression, leading to activation of epithelial-mesenchymal transition (EMT). Rescue experiments suggested that the oncogenic activity of circ-0005105 was dependent on the modulation of the miR-20a-3p-COL11A1 axis. More importantly, COL11A1 overexpression was significantly associated with poor prognosis in PDAC, and silencing COL11A1 reduced PDAC cell tumorigenicity and metastasis. Taken together, our findings confirm for the first time that circ-0005105 has critical functions by regulating the miR-20a-3p-COL11A1 axis. In the clinic, circ-0005105 can act as a potential prognostic marker and therapeutic target in PDAC.


Assuntos
Carcinoma Ductal Pancreático/metabolismo , Colágeno Tipo XI/metabolismo , MicroRNAs/metabolismo , Neoplasias Pancreáticas/metabolismo , RNA Circular/metabolismo , Animais , Carcinoma Ductal Pancreático/genética , Carcinoma Ductal Pancreático/secundário , Linhagem Celular Tumoral , Movimento Celular , Proliferação de Células , Colágeno Tipo XI/genética , Bases de Dados Genéticas , Progressão da Doença , Transição Epitelial-Mesenquimal , Regulação Neoplásica da Expressão Gênica , Humanos , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/metabolismo , Neoplasias Pulmonares/secundário , Camundongos Endogâmicos BALB C , Camundongos Nus , MicroRNAs/genética , Invasividade Neoplásica , Neoplasias Pancreáticas/genética , Neoplasias Pancreáticas/patologia , RNA Circular/genética , Transdução de Sinais
14.
Ann Palliat Med ; 10(5): 5902-5907, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-34107726

RESUMO

We report an extremely rare case of primary gastric melanoma with pancreatic metastasis. As far as we know, the concept of primary gastrointestinal melanoma is currently controversial, because there are very few reports of primary gastrointestinal melanoma. At the same time, isolated pancreatic metastases are also very rare. The patient was admitted to the hospital with a main complaint of decreased appetite, and then underwent gastroscopy and found a mass in the stomach. The mass was initially diagnosed as poorly differentiated adenocarcinoma following a gastroscopic biopsy. The patient underwent radical total gastrectomy, pancreatic body and tail resection, splenectomy, and Roux-en-Y esophagojejunostomy. After further immunohistochemical examination of the surgically removed tissue, malignant melanoma was diagnosed. The tumor cells were arranged in sheets or nests with infiltrating growth, the cell sizes were inconsistent, nucleoli were obvious, and melanin particles were seen in the cytoplasm of some cells. The tumor cells were positive for MITF and S-100. Detailed systemic and imaging examinations did not find any other primary lesions. The patient denied any melanoma and skin lesion history. We believe this is a manifestation of primary gastric melanoma. We report this rare case of gastric melanoma with the aim of increasing clinicians' awareness of non-cutaneous melanoma and its treatment methods.


Assuntos
Melanoma , Neoplasias Pancreáticas , Neoplasias Gástricas , Gastrectomia , Humanos , Neoplasias Pancreáticas/diagnóstico por imagem , Neoplasias Gástricas/diagnóstico por imagem
15.
Chemistry ; 27(18): 5761-5768, 2021 Mar 26.
Artigo em Inglês | MEDLINE | ID: mdl-33469957

RESUMO

Nanoscale composites for high-performance electrodes employed in flexible, all-solid-state supercapacitors are being developed. A series of binder-free composites, each consisting of a transition bimetal oxide, a metal oxide, and a metal nitride grown on N-doped reduced graphene oxide (rGO)-wrapped nickel foam are obtained by using a universal strategy. Three different transition metals, Co, Mo, and Fe, are separately compounded with nickel ions, which originate from the nickel foam, to form three composites, NiCoO2 @Co3 O4 @Co2 N, NiMoO4 @MoO3 @Mo2 N, and NiFe2 O4 @Fe3 O4 @Fe2 N, respectively. These as-prepared active materials have similar regular variation patterns in their properties, including better conductivity and battery-mimicking pseudocapacitance, which result in their high whole-electrode capacitance performance [2598.3 F g-1 (39.85 F cm-2 ), 3472.6 F g-1 (41.43 F cm-2 ) and 1907.5 F g-1 (3.41 F cm-2 ) for the composites incorporating Co, Mo, and Fe, respectively]. The as-assembled flexible, all-solid-state NiCoO2 @Co3 O4 @Co2 N//KOH/PVA//NiCoO2 @Co3 O4 @Co2 N device can be easily bent and exhibits high energy density and power density of 92.8 Wh kg-1 and 1670.4 W kg-1 , respectively. The universality of this design strategy could allow it to be employed in producing hybrid materials for high-performance energy-storage devices.

16.
Ann Transl Med ; 8(19): 1234, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-33178766

RESUMO

BACKGROUND: Activating transcription factor 2 (ATF2) regulates the expression of downstream target genes and is phosphorylated by the Ras-extracellular-signal-regulated kinase (ERK) pathway. Acetylation of ATF2 is necessary for this type of regulation. However, the molecular mechanism by which the Ras-ERK pathway mediates the regulation of acetylated ATF2 is unknown. This study investigates the mechanism of Ras-ERK pathway-mediated regulation of acetylated ATF2 in maintaining the characteristic phenotype of pancreatic cancer cells. METHODS: This study was carried out using ASPC-1 and BXPC-3 pancreatic cancer cell lines transfected with the double mutant RasG12V/T35S. The levels of phosphorylated ERK1/2 were measured to establish the activated Ras-ERK pathway. The regulation of acetylated ATF2 was examined by detecting the protein level using western blotting, and the effects on cancer cell phenotype were measured using cell viability, proliferation, migration, and apoptosis assays. Also, chromatin immunoprecipitation (ChIP) assays were used to measure the effect on respective downstream target genes. RESULTS: The results showed that RasG12V/T35S reduced the level of acetylated ATF2 in ASPC-1 and BXPC-3 cells. Compared to wild-type ATF2, the mutant ATF2K357Q (which mimics the irreversible acetylated form of ATF2) reduced the cancer cell phenotype and showed decreased enrichment on target genes upon transfection with Ras. Moreover, the level of acetylated ATF2 was regulated by the degradation of p300 through E3 ubiquitin ligase mouse double minute 2 homolog (MDM2). CONCLUSIONS: Activation of the Ras-ERK pathway regulates acetylated ATF2 through degradation of p300 via a proteasome-dependent pathway, which alters the transcription of downstream target genes responsible for the cancer cell phenotype.

17.
Int J Mol Sci ; 21(18)2020 Sep 14.
Artigo em Inglês | MEDLINE | ID: mdl-32938013

RESUMO

Orthotopic liver transplantation (OLT) using allografts from donation after circulatory death (DCD) is potentially associated with compromised clinical outcomes due to ischemia-reperfusion injury (IRI)-induced organ damage and graft-related complications. The aim of this study was to provide in vivo data on the effects of adenosine A2a receptor stimulation in a clinically relevant large animal model of DCD liver transplantation. Cardiac arrest was induced in German Landrace pigs (n = 10; 20-25 kg). After 30 min of warm ischemia, the donor liver was retrieved following a cold flush with 3 L of histidine-tryptophan-ketoglutarate-HTK solution. Animals of the treatment group (n = 5/group) received a standard dose of the selective adenosine receptor agonist CGS 21680 added to the cold flush. All grafts were stored for 4.5 h at 4 °C in HTK-solution before OLT. Hepatocellular injury, apoptosis, protein kinase A-PKA activity, graft microcirculation, liver function, and animal survival were assessed. Compared to untreated livers, adenosine A2a receptor stimulation resulted in improved tissue microcirculation (103% ± 5% vs. 38% ± 4% compared to baseline; p < 0.05), accelerated functional recovery of the graft (indocyanine green-plasma disappearance rate (ICG-PDR) of 75% ± 18% vs. 40% ± 30% after 3 h), increased PKA activity ratio (56% ± 3% vs. 32% ± 3%; p < 0.001 after 1 h), and consequently reduced tissue necrosis and apoptosis. The potent protective effects were clinically manifested in significantly improved survival in the treatment group after 72 h (100% vs. 40%; p = 0.04). The ex vivo administration of adenosine A2a receptor agonist during the back-table flush mitigates IRI-mediated tissue damage and improves functional graft recovery and survival in a large animal model of DCD liver transplantation.


Assuntos
Agonistas do Receptor A2 de Adenosina/farmacologia , Transplante de Fígado/mortalidade , Receptor A2A de Adenosina/metabolismo , Traumatismo por Reperfusão/tratamento farmacológico , Traumatismo por Reperfusão/mortalidade , Adenosina/análogos & derivados , Adenosina/farmacologia , Animais , Modelos Animais de Doenças , Feminino , Glucose/farmacologia , Fígado/efeitos dos fármacos , Fígado/metabolismo , Doadores Vivos , Manitol/farmacologia , Preservação de Órgãos/métodos , Soluções para Preservação de Órgãos/farmacologia , Fenetilaminas/farmacologia , Cloreto de Potássio/farmacologia , Procaína/farmacologia , Traumatismo por Reperfusão/metabolismo , Suínos , Isquemia Quente/métodos
18.
Life Sci ; 256: 117936, 2020 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-32531376

RESUMO

AIMS: The regulation of the Ras-ERK pathway is the crucial point in pancreatic carcinogenesis, and the Ras kinase is an essential regulatory upstream signal molecule of the ERK1/2 pathway. H3K9ac is a vital histone modification, but its specific role in pancreatic cancer remains unclear. This research aims to study whether the modification level of H3K9ac can regulate the characteristic phenotype of the pancreatic cancer cells by affecting the downstream expression, proliferation, migration, and other related genes. MAIN METHODS: The RasG12V/T35S were used to transfect pancreatic cancer cells, and the levels of phosphorylated ERK1/2 and H3K9ac were detected by western blotting. The colony formation assay, transwell assay, and chromatin immunoprecipitation assay were used to study cell viability, migration, and the downstream genes of the ERK1/2 pathway. KEY FINDINGS: The results showed that Ras ERK1/2 reduced H3K9ac expression in ASPC-1 cells, and H3K9ac significantly repressed the viability of cells, colony formation, and ASPC-1 cell movement induced by Ras ERK1/2. Besides, HDAC1 silencing increased H3K9ac expression, and changed the effect of Ras ERK1/2 on ASPC-1 cells proliferation, its movement, and mRNAs of ERK1/2 downstream genes. Moreover, Ras ERK1/2 inhibited H3K9ac expression by the degradation of PCAF via MDM2. SIGNIFICANCE: Ras ERK1/2 promotes pancreatic carcinogenesis cell movement, through down-regulating H3K9ac via MDM2 mediated PCAF degradation.


Assuntos
Carcinogênese/patologia , Histonas/metabolismo , Lisina/metabolismo , Sistema de Sinalização das MAP Quinases , Neoplasias Pancreáticas/metabolismo , Neoplasias Pancreáticas/patologia , Fatores de Transcrição de p300-CBP/metabolismo , Proteínas ras/metabolismo , Acetilação , Carcinogênese/genética , Carcinogênese/metabolismo , Linhagem Celular Tumoral , Movimento Celular , Proliferação de Células , Regulação Neoplásica da Expressão Gênica , Inativação Gênica , Histona Desacetilase 1/metabolismo , Humanos , Neoplasias Pancreáticas/genética , Fenótipo , Proteólise , Proteínas Proto-Oncogênicas c-mdm2/metabolismo , Transdução de Sinais , Transcrição Gênica
19.
Research (Wash D C) ; 2020: 3976278, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32159161

RESUMO

Electrochemical water splitting driven by clean and sustainable energy sources to produce hydrogen is an efficient and environmentally friendly energy conversion technology. Water splitting involves hydrogen evolution reaction (HER) and oxygen evolution reaction (OER), in which OER is the limiting factor and has attracted extensive research interest in the past few years. Conventional noble-metal-based OER electrocatalysts like IrO2 and RuO2 suffer from the limitations of high cost and scarce availability. Developing innovative alternative nonnoble metal electrocatalysts with high catalytic activity and long-term durability to boost the OER process remains a significant challenge. Among all of the candidates for OER catalysis, self-supported layered double hydroxides (LDHs) have emerged as one of the most promising types of electrocatalysts due to their unique layered structures and high electrocatalytic activity. In this review, we summarize the recent progress on self-supported LDHs and highlight their electrochemical catalytic performance. Specifically, synthesis methods, structural and compositional parameters, and influential factors for optimizing OER performance are discussed in detail. Finally, the remaining challenges facing the development of self-supported LDHs are discussed and perspectives on their potential for use in industrial hydrogen production through water splitting are provided to suggest future research directions.

20.
Dig Dis Sci ; 65(7): 2079-2088, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-31691173

RESUMO

BACKGROUND: Secondary infection is an important factor affecting mortality and quality of life in patients with severe acute pancreatitis. The characteristics of secondary infection, which are well known to clinicians, need to be re-examined in detail, and their understanding among clinicians needs to be updated accordingly. AIM: This study aims to investigate the characteristics and drug resistance of pathogens causing severe acute pancreatitis (SAP) secondary infection, to objectively present infection situation, and to provide reference for improved clinical management. METHODS: A retrospective analysis was performed on 55 consecutive patients with SAP who developed secondary infection with an accurate evidence of bacterial/fungal culture from 2016 to 2018. The statistics included the spectrum and distribution of pathogens, the drug resistance of main pathogens, and associations between multiple infectious parameters and mortality. RESULTS: A total of 181 strains of pathogens were isolated from (peri)pancreas; bloodstream; and respiratory, urinary, and biliary systems in 55 patients. The strains included 98 g-negative bacteria, 58 g-positive bacteria, and 25 fungi. Bloodstream infection (36.5%) was the most frequent infectious complication, followed by (peri)pancreatic infection (32.0%). Acinetobacter baumannii, Pseudomonas aeruginosa, Klebsiella pneumoniae, Escherichia coli, and Stenotrophomonas maltophilia were predominant among gram-negative bacteria. Gram-positive bacterial infections were mainly caused by Enterococcus faecium and Staphylococcus spp. Fungal infections were predominantly caused by Candida spp. The drug resistance of pathogens causing SAP secondary infection was generally higher than the surveillance level. Patients in the death group were older (55 ± 13 years vs. 46 ± 14 years; p = 0.039) and had longer intensive care unit (ICU) stay (14 vs. 8; p = 0.026) than those in the survival group. A. baumannii infection (68.4% vs. 33%; p = 0.013), number of pathogens ≥ 4 (10 vs. 6; p = 0.005), pancreatic infection (14 vs. 15, p = 0.024), and urinary infection (8 vs. 5; p = 0.019) were significantly associated with mortality. CONCLUSION: Gram-negative bacteria are the main pathogens causing SAP secondary infection, in which nosocomial infections play a major role. The drug resistance profile of gram-negative bacteria is seriously threatening, and the commonly used antibiotics in SAP are gradually losing their effectiveness. Much attention should be paid to the rational use of antibiotics, and strategies should be established for infection prevention in SAP.


Assuntos
Candidíase/microbiologia , Infecção Hospitalar/microbiologia , Resistência Microbiana a Medicamentos , Infecções por Bactérias Gram-Negativas/microbiologia , Infecções por Bactérias Gram-Positivas/microbiologia , Pancreatite/terapia , Acinetobacter baumannii , Adulto , Idoso , Bacteriemia/complicações , Bacteriemia/tratamento farmacológico , Bacteriemia/microbiologia , Bacteriemia/mortalidade , Doenças Biliares/complicações , Doenças Biliares/tratamento farmacológico , Doenças Biliares/microbiologia , Doenças Biliares/mortalidade , Candida , Candidemia/complicações , Candidemia/tratamento farmacológico , Candidemia/microbiologia , Candidemia/mortalidade , Candidíase/complicações , Candidíase/tratamento farmacológico , Candidíase/mortalidade , Causas de Morte , Coinfecção/complicações , Coinfecção/tratamento farmacológico , Coinfecção/microbiologia , Coinfecção/mortalidade , Infecção Hospitalar/complicações , Infecção Hospitalar/tratamento farmacológico , Infecção Hospitalar/mortalidade , Enterococcus faecium , Escherichia coli , Feminino , Infecções por Bactérias Gram-Negativas/complicações , Infecções por Bactérias Gram-Negativas/tratamento farmacológico , Infecções por Bactérias Gram-Negativas/mortalidade , Infecções por Bactérias Gram-Positivas/complicações , Infecções por Bactérias Gram-Positivas/tratamento farmacológico , Infecções por Bactérias Gram-Positivas/mortalidade , Mortalidade Hospitalar , Hospitais de Ensino , Hospitais Universitários , Humanos , Unidades de Terapia Intensiva , Infecções Intra-Abdominais/complicações , Infecções Intra-Abdominais/tratamento farmacológico , Infecções Intra-Abdominais/microbiologia , Infecções Intra-Abdominais/mortalidade , Klebsiella pneumoniae , Tempo de Internação , Masculino , Pessoa de Meia-Idade , Pancreatite/complicações
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