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1.
Bioresour Technol ; 369: 128472, 2023 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-36509306

RESUMEN

Machine learning methods have recently shown a broad application prospect in biomass gasification modeling. However, a significant drawback of the machine learning approaches is their poor physical interpretability when relying on limited experimental data. In the present work, a physics-informed neural network method (PINN) is developed to predict biomass gasification products (N2, H2, CO, CO2, and CH4). PINN simultaneously considers regression, structure, and physical monotonicity constraints in the loss function, providing physically feasible predictions. Specifically, the PINN models have outperformed prediction capability (average test R2 0.91-0.97) compared to five other machine learning methods through 50 times random sample classifications. Furthermore, it is demonstrated that the developed models can maintain correct monotonicity even if the feedstock characteristics or gasification conditions are outside the training data. By using a reliable physical mechanism to guide machine learning, the model can ensure better generalizability and scientific interpretability.


Asunto(s)
Biomasa , Gases , Aprendizaje Automático , Modelos Teóricos , Redes Neurales de la Computación , Física , Gases/química
2.
Int J Mol Sci ; 20(13)2019 Jun 28.
Artículo en Inglés | MEDLINE | ID: mdl-31261843

RESUMEN

The antioxidant effect of salidroside has been proven, but its role in liver injury is poorly understood. In this study, we aimed to evaluate the protective effects and mechanism of salidroside on liver injury induced by carbon tetrachloride (CCl4) in vivo. Mice were pretreated with salidroside (60 mg/kg, intraperitoneally injected, i.p.) once per day for 14 consecutive days and then administered with CCl4 (15.95 g/kg, i.p.) for 24 h to produce a liver injury model. Salidroside attenuated hepatic transaminase elevation in serum and ameliorated liver steatosis and necrosis, thereby suggesting its protective effect on the liver. Salidroside antagonized CCl4-induced toxicity by equilibrating antioxidation system, thereby inhibiting reactive oxygen species accumulation, and restoring mitochondrial structure and function. Salidroside exerts antioxidant and liver-protective effects by selectively inhibiting the activation of genes, including growth arrest and DNA -damage-inducible 45 α (Gadd45a), mitogen-activated protein kinase 7 (Mapk7), and related RAS viral oncogene homolog 2 (Rras2), which induce oxidative stress in the mitogen-activated protein kinase pathway. These results revealed that salidroside can protect the liver from CCl4-induced injury by resisting oxidative stress and protecting mitochondrial function.


Asunto(s)
Antioxidantes , Enfermedad Hepática Inducida por Sustancias y Drogas , Glucósidos , Mitocondrias Hepáticas , Estrés Oxidativo , Fenoles , Animales , Masculino , Ratones , Antioxidantes/farmacología , Antioxidantes/uso terapéutico , Tetracloruro de Carbono/toxicidad , Proteínas de Ciclo Celular/genética , Proteínas de Ciclo Celular/metabolismo , Enfermedad Hepática Inducida por Sustancias y Drogas/tratamiento farmacológico , Enfermedad Hepática Inducida por Sustancias y Drogas/metabolismo , Enfermedad Hepática Inducida por Sustancias y Drogas/prevención & control , Glucósidos/farmacología , Glucósidos/uso terapéutico , Sistema de Señalización de MAP Quinasas , Proteínas de la Membrana/genética , Proteínas de la Membrana/metabolismo , Proteínas Asociadas a Microtúbulos/genética , Proteínas Asociadas a Microtúbulos/metabolismo , Mitocondrias Hepáticas/efectos de los fármacos , Mitocondrias Hepáticas/metabolismo , Proteínas de Unión al GTP Monoméricas/genética , Proteínas de Unión al GTP Monoméricas/metabolismo , Fenoles/farmacología , Fenoles/uso terapéutico
3.
Wideochir Inne Tech Maloinwazyjne ; 13(2): 227-232, 2018 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-30002756

RESUMEN

INTRODUCTION: Vertebral artery stenosis is a major cause of posterior circulation ischemia in the elderly. There is not a clear consensus on the optimal therapeutic approach for symptomatic extracranial vertebral artery stenosis. AIM: To evaluate the feasibility and efficacy of balloon-expandable stent angioplasty in the treatment of vertebral artery stenosis in the V2 segment. MATERIAL AND METHODS: Five patients with vertebral artery stenosis (V2 segment) and treatment of percutaneous transluminal stenting from July 2009 to June 2014 were retrospectively evaluated. All patients underwent color Doppler, transcranial color Doppler (TCD), CT angiography (CTA) and cerebral digital subtraction angiography (DSA) preoperatively. Whether there was osseous oppression was determined according to neck computed tomography (CT) and CTA. After the surgery, angiography was performed to determine if there was infarction or bleeding in the intracranial vertebral artery, basilar artery and posterior cerebral artery. The surgical parameters, residual stenosis, complications, etc. were recorded and evaluated. The patients were followed up accordingly. RESULTS: Five patients (3 males, 2 females; average age of 66 ±4.2, range of 54-75) were enrolled in the study. Balloon-expandable stents were successfully implanted in the 5 patients. The mean residual stenosis after the balloon-expandable stenting (preoperative: average, 87.0 ±6.6%, range: 75-93%) was 12.6 ±7.8% (range: 5-25%). The clinical symptoms disappeared or receded. No serious complications occurred. CONCLUSIONS: The balloon-expandable stent angioplasty seemed to be feasible and efficacious in treating vertebral artery stenosis in the V2 segment. Further study with a large sample size is needed.

4.
Int J Surg ; 33 Pt A: 42-8, 2016 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-27452300

RESUMEN

INTRTODUCTION: Osteoporotic vertebral collapse (OVC) with delayed neurological deficits (DND) is one severe subtype of OVC, for which surgical intervention is more complicated and difficult. Although many individual case reports and series have described the surgery for stabilization and neurological decompression of OVC with DND, no systematic review has been published. METHODS: We searched eligible studies in PubMed, SCOPUS, EMBASE and ISIWeb of Knowledge for eligible studies and conducted comprehensive analysis. RESULTS: A total of 29 publications involving 596 patients of OVC with DND were included in this review. There are 36.6%, 60.6% and 2.8% of patients receiving anterior neural decompression and reconstruction, posterior surgery which can be further divided into 6 distinct groups, and posteroanterior surgery, respectively. Among them, patients in the posteroanterior surgery had the longest time (351.0 min) for operation and the largest volume of mean blood loss (2892.0 ml). For clinical outcomes, patients in the posterior spinal shortening osteotomy with direct neural decompression group had the most significantly LKA correction effect, with mean LKA correction 21.3°, while the posterior decompression and posterior column reconstruction group exhibited the lowest LKA correction loss rate (14.7%). CONCLUSION: Although the optimal treatment has not been determined for patients of OVC with DND in this study, our analysis could provide guidance for choosing an appropriate approach. Besides, effective treatment for OVC with DND requires multidisciplinary collaboration, such as geriatricians, interventional radiologists, respiratory disease experts, and spine surgeons. On light of the above analysis, we believe that individualized surgical approach should be introduced based on the clinical characteristics of each patient.


Asunto(s)
Fracturas por Compresión/cirugía , Enfermedades del Sistema Nervioso/terapia , Fracturas Osteoporóticas/cirugía , Fracturas de la Columna Vertebral/cirugía , Descompresión Quirúrgica/métodos , Fracturas por Compresión/complicaciones , Humanos , Vértebras Lumbares/cirugía , Enfermedades del Sistema Nervioso/etiología , Fracturas Osteoporóticas/complicaciones , Estudios Retrospectivos , Fracturas de la Columna Vertebral/complicaciones , Fusión Vertebral/métodos , Estenosis Espinal/complicaciones , Vértebras Torácicas/lesiones , Resultado del Tratamiento
5.
Exp Ther Med ; 11(5): 1983-1986, 2016 May.
Artículo en Inglés | MEDLINE | ID: mdl-27168838

RESUMEN

Internal carotid artery dissection (ICAD) is a major cause of ischemic stroke in young and middle-aged patients. Patients may be asymptomatic or present with symptoms ranging from headache and neck pain to severe cerebral ischemic events. Conventional treatment is medical anticlotting therapy or involves the use of interventional tools, such as endovascular treatment. Anticoagulation or antiplatelet therapy are the primary treatment modalities used to prevent thromboembolic complications from arterial dissections, however, they are unsuitable in certain cases of dissecting aneurysms. In the current study reports the case of a 52-year-old male patient presenting with the primary complaint of left limb weakness. Computed tomography angiography revealed a right ICAD located in the oropharyngeal segment. Subsequently, digital subtraction angiography was performed to assess the oropharyngeal segment. Antithrombotic therapy resulted in no improvement; therefore, endovascular treatment with the insertion of a Willis covered stent was performed, resulting in an improved outcome.

6.
Zhongguo Gu Shang ; 26(3): 252-6, 2013 Mar.
Artículo en Chino | MEDLINE | ID: mdl-23795450

RESUMEN

OBJECTIVE: To evaluate the value of the Centerpiece plate in the cervical single open-door laminoplasty and compared its advantages with conventional suture fixation methods. METHODS: From December 2009 to August 2011,32 patients with cervical spondylotic myelopathy were treated with operation. Of them, 15 cases underwent cervical single open-door laminoplasty and Centerpiece plate fixation (group A),there were 8 males and 7 females,aged from 51 to 65 years old with an average of 60.5 years and ranged in course of disease from 2 to 15 months; 17 cases underwent cervical single open-door laminoplasty and silk suture fixation (group B), there were 9 males and 8 females, aged from 49 to 66 years old with an average of 61.5 years and ranged in course of disease from 1 to 14 months. All the patients with unsteady gait symptom before operation and cervical MR imaging showed spinal cord compression and denaturation. According to standard of Japanese Orthopaedics Association (JOA) to evaluate the spinal nervers function before operation and at 6 months after operation;according to CT scan to determine the sagittal diameter (AP) of upper vertebral canal and cervical activity (ROM). RESULTS: All the patients were followed up from 8 to 20 months with an average of 13 months. All the incisions healed well and no complications such as internal fixation loosening and breakage,spinal cord injury, reclose-door were found. Postoperative symptoms relieved obviously and MRI and CT showed vertebral canal volume expanded significantly. Operative time and blood loss in group A were respectively (155.0+/-12.3) min, (407.0+/-11.8) ml and in group B were respectively (148.0+/-14.4) min, (398.0+/-15.4) ml. There was no significantly differenc, between two groups (P>0.05). JOA score in group A improved from preoperative 9.1+/-2.6 to postoperative 15.5+/-1.8 and in group B improved from preoperative 9.3 +/- 2.1 to postoperative 13.1 +/- 2.5 (P<0.05). CT sagittal diameter (AP) in group A increased from preoperative (10.7+/-2.4) mm to postoperative (17.6+/-3.2) mm and in group B increased from preoperative (11.6+/-1.7) mm to postoperative (15.9+/-2.0) mm (P<0.05). Cervical activity (ROM) in group A be- fore and after operation were respectively (51.0+/-2.6) degrees, (45.0+/-3.5) degrees and in group B were respectively (52.0+/-1.8) and (42.0+/-2.4). There was no significantly difference before operation between two groups (P>0.05) and there was significantly difference after operation between two groups (P<0.05). CONCLUSION: Treatment of cervical spondylotic myelopathy with posterior single open-door laminoplasty and Centerpiece plate fixation can enlarge spinal canal volume,keep original cervical activity, improve postoperative JOA score. The method has obviously advantages compared with traditional suture fixation methods.


Asunto(s)
Placas Óseas , Vértebras Cervicales/cirugía , Laminectomía/métodos , Espondilosis/cirugía , Anciano , Femenino , Humanos , Masculino , Persona de Mediana Edad , Canal Medular/cirugía , Espondilosis/etiología
7.
Zhong Yao Cai ; 31(7): 1024-7, 2008 Jul.
Artículo en Chino | MEDLINE | ID: mdl-18973022

RESUMEN

OBJECTIVE: To compare alpha-glycosidase inhibitor microamount screening models which are established by two different resources alpha-glycosidase to screen the Chinese herbal medicines which have great alpha-glycosidase inhibition. METHODS: Comparing the activities of two different resources alpha-glycosidase with glucose oxidase method, then establishing optimal reaction conditions. Extracting the water soluble compositions of Chinese gallnut, paeoniae radix, Glycyrrhiza, rhubarb, fructus by boiling ,then using the alpha-glycosidase inhibition model to check and compare their alpha-glycosidase inhibitions. RESULTS: Five Chinese herbal medicines all had alpha-glycosidase inhibition, and the greatest was Chinese gallnut. CONCLUSION: The activities of two resources alpha-glycosidase are certainly different, but they do not have significant influence on findings of screening alpha-glycosidase inhibitors in vitro. Water soluble compositions of five Chinese herbal medicines have alpha-glycosidase inhibition.


Asunto(s)
Medicamentos Herbarios Chinos/farmacología , Inhibidores de Glicósido Hidrolasas , Plantas Medicinales/química , Acarbosa/farmacología , Animales , Cornus/química , Medicamentos Herbarios Chinos/aislamiento & purificación , Glycyrrhiza uralensis/química , Mucosa Intestinal/enzimología , Plantas Medicinales/clasificación , Ranunculaceae/química , Ratas , Rheum/química , Factores de Tiempo , alfa-Glucosidasas/aislamiento & purificación , alfa-Glucosidasas/metabolismo
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