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1.
Entropy (Basel) ; 25(8)2023 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-37628181

RESUMEN

This article focuses on entropy generation in the combustion field, which serves as a useful indicator to quantify the interaction between turbulence and combustion. The study is performed on the direct numerical simulations (DNS) of high pressure non-premixed and premixed swirling flames. By analyzing the entropy generation in thermal transport, mass transport, and chemical reactions, it is found that the thermal transport, driven by the temperature gradient, plays a dominant role. The enstrophy transport analysis reveals that the responses of individual terms to combustion can be measured by the entropy: the vortex stretching and the dissipation terms increase monotonically with the increasing entropy. In high entropy regions, the turbulence behaves as the "cigar shaped" state in the non-premixed flame, while as the axisymmetric state in the premixed flame. A substantial increase in the normal Reynolds stress with the entropy is observed. This is due to the competition between two terms promoted by the entropy, i.e., the velocity-pressure gradient correlation term and the shear production term. As a result, the velocity-pressure gradient correlation tends to isotropize turbulence by transferring energy increasingly from the largest streamwise component to the other smaller normal components of Reynolds stress and is dominated by the fluctuating pressure gradient that increases along the entropy. The shear production term increases with the entropy due to the upgrading alignment of the eigenvectors of strain rate and Reynolds stress tensors.

2.
Biochem Biophys Res Commun ; 550: 15-21, 2021 04 23.
Artículo en Inglés | MEDLINE | ID: mdl-33677131

RESUMEN

Liver ischemia-reperfusion (IR) injury is an unavoidable pathological process in transplantation, closely related to poor prognosis. To date, there has been no clear therapeutic measure. We previously reported that mild hypothermia (MH), a widely used therapy, can exert significant protective effect against liver IR injury. Among the multiple mechanisms underlying the therapeutic effect of MH, autophagy flux drew our special attention. In this study, we evaluated the role of autophagy flux in IR injury and thereby explored the relationship between MH and autophagy flux in IR injury. We developed in vivo and in vitro models for hepatic IR injury. By autophagy flux assay with Western blotting and immunofluorescence, we found that MH restricts heavy accumulation of autophagosomes (APs) during IR injury. Activation and blocking of the autophagy flux unraveled that accumulation of APs further aggravated IR injury. Further, MH reduces APs accumulation to restore autophagy flux by regulating the fusion of APs and lysosomes. Besides, MH upregulated the level of Rab7 protein expression that was seriously impaired during IR injury. Inhibition of Rab7 expression increased apoptosis of liver cells and reduced the degree of overlap between APs and lysosomes. The results were reversed upon activation of Rab7. In conclusion, MH can alleviate liver IR injury by regulating the Rab7-mediated APs-lysosomes fusion that reduces APs accumulation. This can provide a theoretical basis for the further application of MH in related clinical diseases.


Asunto(s)
Autofagosomas/metabolismo , Hipotermia Inducida , Hígado/citología , Lisosomas/metabolismo , Fusión de Membrana , Daño por Reperfusión/prevención & control , Proteínas de Unión al GTP rab/metabolismo , Animales , Autofagia , Hígado/lesiones , Masculino , Ratones , Proteínas de Unión a GTP rab7
3.
Innovation (Camb) ; 5(4): 100655, 2024 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-39040688

RESUMEN

Micro(nano)plastics (MNPs) have become a significant environmental concern due to their widespread presence in the biosphere and potential harm to ecosystems and human health. Here, we propose for the first time a MNPs capture, utilization, and storage (PCUS) concept to achieve MNPs remediation from water while meeting economically productive upcycling and environmentally sustainable plastic waste management. A highly efficient capturing material derived from surface-modified woody biomass waste (M-Basswood) is developed to remove a broad spectrum of multidimensional and compositional MNPs from water. The M-Basswood delivered a high and stable capture efficiency of >99.1% at different pH or salinity levels. This exceptional capture performance is driven by multiscale interactions between M-Basswood and MNPs, involving physical trapping, strong electrostatic attractions, and triggered MNPs cluster-like aggregation sedimentation. Additionally, the in vivo biodistribution of MNPs shows low ingestion and accumulation of MNPs in the mice organs. After MNPs remediation from water, the M-Basswood, together with captured MNPs, is further processed into a high-performance composite board product where MNPs serve as the glue for utilization and storage. Furthermore, the life cycle assessment (LCA) and techno-economic analysis (TEA) results demonstrate the environmental friendliness and economic viability of our proposed full-chain PCUS strategy, promising to drive positive change in plastic pollution and foster a circular economy.

4.
Cell Death Dis ; 12(2): 211, 2021 02 24.
Artículo en Inglés | MEDLINE | ID: mdl-33627626

RESUMEN

Ischemia-reperfusion injury (IRI) is an inevitable and serious clinical problem in donations after heart death (DCD) liver transplantation. Excessive sterile inflammation plays a fateful role in liver IRI. Hypothermic oxygenated perfusion (HOPE), as an emerging organ preservation technology, has a better preservation effect than cold storage (CS) for reducing liver IRI, in which regulating inflammation is one of the main mechanisms. HECTD3, a new E3 ubiquitin ligase, and TRAF3 have an essential role in inflammation. However, little is known about HECTD3 and TRAF3 in HOPE-regulated liver IRI. Here, we aimed to investigate the effects of HOPE on liver IRI in a DCD rat model and explore the roles of HECTD3 and TRAF3 in its pathogenesis. We found that HOPE significantly improved liver damage, including hepatocyte and liver sinusoidal endothelial cell injury, and reduced DCD liver inflammation. Mechanistically, both the DOC and HECT domains of HECTD3 directly interacted with TRAF3, and the catalytic Cys (C832) in the HECT domain promoted the K63-linked polyubiquitination of TRAF3 at Lys138. Further, the ubiquitinated TRAF3 at Lys138 increased oxidative stress and activated the NF-κB inflammation pathway to induce liver IRI in BRL-3A cells under hypoxia/reoxygenation conditions. Finally, we confirmed that the expression of HECTD3 and TRAF3 was obviously increased in human DCD liver transplantation specimens. Overall, these findings demonstrated that HOPE can protect against DCD liver transplantation-induced-liver IRI by reducing inflammation via HECTD3-mediated TRAF3 K63-linked polyubiquitination. Therefore, HOPE regulating the HECTD3/TRAF3 pathway is a novel target for improving IRI in DCD liver transplantation.


Asunto(s)
Hipotermia Inducida , Circulación Hepática , Hígado/irrigación sanguínea , Hígado/cirugía , Preservación de Órganos , Perfusión , Daño por Reperfusión/prevención & control , Factor 3 Asociado a Receptor de TNF/metabolismo , Ubiquitina-Proteína Ligasas/metabolismo , Animales , Hipoxia de la Célula , Línea Celular , Modelos Animales de Enfermedad , Hepatectomía , Humanos , Mediadores de Inflamación/metabolismo , Hígado/metabolismo , Hígado/patología , Trasplante de Hígado , Masculino , Estrés Oxidativo , Ratas Sprague-Dawley , Daño por Reperfusión/genética , Daño por Reperfusión/metabolismo , Daño por Reperfusión/patología , Factor 3 Asociado a Receptor de TNF/genética , Recolección de Tejidos y Órganos , Ubiquitina-Proteína Ligasas/genética , Ubiquitinación
5.
Front Neurol ; 11: 600, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32849166

RESUMEN

Parkinson's disease (PD) is a progressive neurodegenerative disorder, and the rate of progression is different across individuals. Subthalamic nucleus deep brain stimulation (STN-DBS) has been shown to produce long-term symptom improvement in PD. In this retrospective study, we wanted to explore the effects of bilateral STN-DBS in PD patients with different rates of disease progression. Forty patients with PD were included. An index of progression rate was calculated by the ratio of the Unified Parkinson Disease Rating Scale, part III (UPDRS-III), score in the off-medication condition at baseline and disease duration. The patients were divided into fast-, medium-, and slow-progression groups by this index. The outcome measurements at the 1st, 6th, and 12th months after surgery were the changes in UPDRS-III scores in the off-medication/on-stimulation condition compared with the baseline. We found the following. (1). Motor functions in the different PD progression groups were improved by bilateral STN-DBS treatment at 1 year of follow-up. (2). However, compared to the slow- and medium-progression groups, the fast-progression group had less improvement at the 6th- and 12th-month follow-up. The results indicated that bilateral STN-DBS can improve motor functions of Parkinson's patients over the 1-year follow-up. Moreover, the outcomes in the slow- and medium-progression patients were better than those with fast-progression rates.

6.
Oxid Med Cell Longev ; 2020: 5849794, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32256954

RESUMEN

Hepatic ischemia-reperfusion (IR) injury is a clinical issue that can result in poor outcome and lacks effective therapies at present. Mild hypothermia (32-35°C) is a physiotherapy that has been reported to significantly alleviate IR injury, while its protective effects are attributed to multiple mechanisms, one of which may be the regulation of fatty acid ß-oxidation (FAO). The aim of the present study was to investigate the role and underlying mechanisms of FAO in the protective effects of mild hypothermia. We used male mice to establish the experimental models as previously described. In brief, before exposure to in situ ischemia for 1 h and reperfusion for 6 h, mice received pretreatment with mild hypothermia for 2 h and etomoxir (inhibitor of FAO) or leptin (activator of FAO) for 1 h, respectively. Then, tissue and blood samples were collected to evaluate the liver injury, oxidative stress, and changes in hepatic FAO. We found that mild hypothermia significantly reduced the hepatic enzyme levels and the score of hepatic pathological injury, hepatocyte apoptosis, oxidative stress, and mitochondrial injury. In addition, the expression of the rate-limiting enzyme (CPT1a) of hepatic FAO was downregulated almost twofold by IR, while this inhibition could be significantly reversed by mild hypothermia. Experiments with leptin and etomoxir confirmed that activation of FAO could also reduce the hepatic enzyme levels and the score of hepatic pathological injury, hepatocyte apoptosis, oxidative stress, and mitochondrial injury induced by IR, which had the similar effects to mild hypothermia, while inhibition of FAO had negative effects. Furthermore, mild hypothermia and leptin could promote the phosphorylation of JAK2/STAT3 and upregulate the ratio of BCL-2/BAX to suppress hepatocyte apoptosis. Thus, we concluded that FAO played an important role in hepatic IR injury and mild hypothermia attenuated hepatic IR injury mainly via the regulation of JAK2/STAT3-CPT1a-dependent FAO.


Asunto(s)
Hipotermia Inducida/métodos , Janus Quinasa 2/metabolismo , Hígado/metabolismo , Daño por Reperfusión/metabolismo , Factor de Transcripción STAT3/metabolismo , Animales , Humanos , Masculino , Ratones , Oxidación-Reducción
7.
Zhongguo Xiu Fu Chong Jian Wai Ke Za Zhi ; 33(4): 440-444, 2019 Apr 15.
Artículo en Zh | MEDLINE | ID: mdl-30983191

RESUMEN

OBJECTIVE: To investigate the feasibility and effectiveness of unexposed ulnar nerve medial elbow incision, open reduction and internal fixation of anatomical locking compression plate (LCP) for distal humerus fractures. METHODS: Fourteen patients with distal humerus fracture were treated between January 2014 and June 2017. There were 5 males and 9 females, aged 18-85 years (mean, 65.5 years). The causes of injury included falling from height in 12 cases and traffic accident in 2 cases, all were closed fractures. Fractures were classified according to the AO/Association for the Study of Internal Fixation (AO/ASIF): 3 cases of type A2, 2 cases of type A3, 4 cases of type B2, 2 cases of type C1, 2 cases of type C2, and 1 case of type C3; without ulnar nerve damage. The time from injury to operation was 4-15 days, with an average of 7 days. The type B2 fractures were treated with unexposed ulnar nerve elbow medial incision and anatomic LCP internal fixation, the rest patients were all treated with unexposed ulnar nerve medial plus conventional lateral approach and bilateral LCP internal fixation. RESULTS: The operation time was 50-140 minutes (mean, 80 minutes), and the intraoperative blood loss was 20-200 mL (mean, 70 mL). There was no blood vessels or nerve damage during operation. All incisions healed by first intension, and no incision infection occurred. All the 14 cases were followed up 9-24 months (mean, 13 months). X-ray films showed that all fractures healed within 4 months without complications such as nonunion and osteomyelitis. No ulnar nerve injury, cubitus varus deformity, and ossifying myositis occurred during follow-up. At last follow-up, the elbow function was assessed by Mayo Elbow Performance score (MEPS), the results were excellent in 8 cases, good in 4 cases, fair in 1 case, and poor in 1 case (type C3 fracture), with the excellent and good rate of 85.7%. CONCLUSION: The unexposed ulnar nerve medial elbow incision can be used effectively to reduct the fracture, and it is not prone to ulnar nerve injury. Combined with the lateral approach to treat the distal humerus fracture, which has the advantages of short operation time, few trauma, little bleeding, and reliable effectiveness.


Asunto(s)
Placas Óseas , Codo , Fijación Interna de Fracturas , Fracturas del Húmero , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Femenino , Fijación Interna de Fracturas/métodos , Humanos , Fracturas del Húmero/cirugía , Húmero , Masculino , Persona de Mediana Edad , Resultado del Tratamiento , Nervio Cubital , Adulto Joven
8.
Zhongguo Xiu Fu Chong Jian Wai Ke Za Zhi ; 32(8): 984-988, 2018 08 15.
Artículo en Zh | MEDLINE | ID: mdl-30238722

RESUMEN

Objective: To explore the effectiveness of maintaining the stability between the fourth and the fifth metacarple base during the treatment in the hamate-metacarpal joint injury. Methods: Between September 2015 and June 2017, 13 cases of hamate-metacarpal joint injury were treated, including 12 males and 1 female, aged from 17 to 55 years (mean, 30.8 years). The injury causes included heavy boxing in 10 cases and falling in 3 cases. There were 2 cases of simple fourth metacarpal basal fracture, 1 basal fracture of the fourth metacarpal bone combined with intermetacarpal ligament fracture, 7 fractures of the fourth and fifth metacarpal base, 2 fourth metacarpal basal fractures combined with the fifth metacarpal basal fracture dislocation, and 1 base fracture of fourth and fifth metacarpal bone combined with hamate bone fracture. The time from injury to operation was 5-11 days (mean, 7.2 days). According to different damage degree and stability change between the fourth and the fifth metacarple base, a preliminary classification was made for different degrees of injury: 2 cases of type Ⅰ, 1 case of type Ⅱ, 7 cases of type Ⅲ, 2 cases of type Ⅳ, and 1 case of type Ⅴ. The patients were treated with corresponding internal fixation methods under the principle of stability recovery between the fourth and fifth metacarple base. Results: All the incisions healed by first intention without infection or skin necrosis. All the 13 patients were followed up 6-18 months with an average of 9.4 months. All fractures healed clinically, and the healing time was 5.5-8.0 weeks with an average of 6.3 weeks. No complication such as plate breakage, fracture dislocation, fracture malunion, and bone nonunion occurred. Hand function was evaluated according to the total active motion (TAM) functional evaluation standard of hand surgery at 6 months after operation, and the results was excellent in 9 cases, good in 3 cases, and fair in 1 case, with an excellent and good rate of 92.3%. Conclusion: Stability between the fourth and fifth metacarple base is of great significance to the classification and the treatment of the hamate-metacarpal joint injury.


Asunto(s)
Fijación Interna de Fracturas , Luxaciones Articulares , Huesos del Metacarpo , Adolescente , Adulto , Placas Óseas , Femenino , Humanos , Luxaciones Articulares/cirugía , Masculino , Huesos del Metacarpo/cirugía , Articulación Metacarpofalángica , Persona de Mediana Edad , Adulto Joven
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