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1Reduction of the closure time of postoperative enterocutaneous fistulas with fibrin sealant显示文摘AIM: To assess whether the use of fibrin sealantshortens the closure time of postoperative enterocutaneous fistulas (ECFs). METHODS: The prospective case-control study included 70 patients with postoperative ECFs with an output of < 500 mL/d, a fistulous tract of > 2 cm and without any local complication. They were divided into study (n = 23) and control groups (n = 47). Esophageal, gastric and colocutaneous fistulas were monitored under endoscopic visualization, which also allowed fibrin glue application directly through the external hole. Outcome variables included closure time, time to resume oral feeding and morbidity related to nutritional support. RESULTS: There were no differences in mean age, fistula output, and follow-up. Closure-time for all patients of the study group was 12.5 ± 14.2 d and 32.5 ± 17.9 d for the control group (P < 0.001), and morbidity related to nutritional support was 8.6% and 42.5%, respectively (P < 0.01). In patients with colonic fistulas, complete closure occurred 23.5 ± 19.5 d after the first application of fibrin glue, and spontaneous closure was observed after 36.2 ± 22.8 d in the control group (P = 0.36). Recurrences were observed in 2 patients because of residual disease. One patient of each group died during follow-up as a consequence of septic complications related to parenteral nutrition. CONCLUSION: Closure time was significantly reduced with the use of fibrin sealant, and oral feeding was resumed faster. We suggest the use of fibrin sealant for the management of stable enterocutaneous fistulas.Jorge Avalos-González Eliseo Portilla-deBuen Caridad Aurea Leal-Cortés Abel Orozco-Mosqueda María del Carmen Estrada-Aguilar Gabriela Abigail Velázquez-Ramírez Gabriela Ambriz-González Clotilde Fuentes-Orozco Aldo Emmerson Guzmán-Gurrola Alejandro González-Ojeda 2010World Journal of Gastroenterology2010,16,22:10
2Prolonged high-fat-diet feeding promotes non-alcoholic fatty liver disease and alters gut microbiota in mice显示文摘BACKGROUND Non-alcoholic fatty liver disease (NAFLD) has become an epidemic largely due to the worldwide increase in obesity. While lifestyle modifications and pharmacotherapies have been used to alleviate NAFLD, successful treatment options are limited. One of the main barriers to finding safe and effective drugs for long-term use in NAFLD is the fast initiation and progression of disease in the available preclinical models. Therefore, we are in need of preclinical models that (1) mimic the human manifestation of NAFLD and (2) have a longer progression time to allow for the design of superior treatments. AIM To characterize a model of prolonged high-fat diet (HFD) feeding for investigation of the long-term progression of NAFLD. METHODS In this study, we utilized prolonged HFD feeding to examine NAFLD features in C57BL/6 male mice. We fed mice with a HFD (60% fat, 20% protein, and 20% carbohydrate) for 80 wk to promote obesity (Old-HFD group, n = 18). A low-fat diet (LFD)(14% fat, 32% protein, and 54% carbohydrate) was administered for the same duration to age-matched mice (Old-LFD group, n = 15). An additional group of mice was maintained on the LFD (Young-LFD, n = 20) for a shorter duration (6 wk) to distinguish between age-dependent and age-independent effects. Liver, colon, adipose tissue, and feces were collected for histological and molecular assessments.RESULTS Prolonged HFD feeding led to obesity and insulin resistance. Histological analysis in the liver of HFD mice demonstrated steatosis, cell injury, portal and lobular inflammation and fibrosis. In addition, molecular analysis for markers of endoplasmic reticulum stress established that the liver tissue of HFD mice have increased phosphorylated Jnk and CHOP. Lastly, we evaluated the gut microbial composition of Old-LFD and Old-HFD. We observed that prolonged HFD feeding in mice increased the relative abundance of the Firmicutes phylum. At the genus level, we observed a significant increase in the abundance of Adercreutzia, Coprococcus, Dorea, and Ruminococcus and decreased relative abundance of Turicibacter and Anaeroplasma in HFD mice. CONCLUSION Overall, these data suggest that chronic HFD consumption in mice can mimic pathophysiological and some microbial events observed in NAFLD patients.Kandy T Velázquez Reilly T Enos Jackie E Bader Alexander T Sougiannis Meredith S Carson Ioulia Chatzistamou James A Carson Prakash S Nagarkatti Mitzi Nagarkatti E Angela Murphy 2019World Journal of Hepatology2019,11,8:6
3Modeling and multi-objective optimization of a gasoline engine using neural networks and evolutionary algorithms显示文摘In this paper, a multi-objective particle swarm optimization (MOPSO) algorithm and a nondominated sorting genetic algorithm Ⅱ (NSGA-Ⅱ) are used to optimize the operating parameters of a 1.6 L, spark ignition (SI) gasoline engine. The aim of this optimization is to reduce engine emissions in terms of carbon monoxide (CO), hydrocarbons (HC), and nitrogen oxides (NOx), which are the causes of diverse environmental problems such as air pollution and global warming. Stationary engine tests were performed for data generation, covering 60 operating conditions. Artificial neural networks (ANNs) were used to predict exhaust emissions, whose inputs were from six engine operating parameters, and the outputs were three resulting exhaust emissions. The outputs of ANNs were used to evaluate objective functions within the optimization algorithms: NSGA-Ⅱ and MOPSO. Then a decision-making process was conducted, using a fuzzy method to select a Pareto solution with which the best emission reductions can be achieved. The NSGA-Ⅱ algorithm achieved reductions of at least 9.84%, 82.44%, and 13.78% for CO, HC, and NOx , respectively. With a MOPSO algorithm the reached reductions were at least 13.68%, 83.80%, and 7.67% for CO, HC, and NOx , respectively.JoséD. MARTíNEZ-MORALES Elvia R. PALACIOS-HERNáNDEZ Gerardo A. VELáZQUEZ-CARRILLO 2013Journal of Zhejiang University-Science A(Applied Physics & Engineering)2013,14,9:6
4Performance Improvement of Artificial Neural Network Model in Short-term Forecasting of Wind Farm Power Output显示文摘Due to the low dispatchability of wind power,the massive integration of this energy source in power systems requires short-term and very short-term wind power output forecasting models to be as efficient and stable as possible.A study is conducted in the present paper of potential improvements to the performance of artificial neural network(ANN)models in terms of efficiency and stability.Generally,current ANN models have been developed by considering exclusively the meteorological information of the wind farm reference station,in addition to selecting a fixed number of time periods prior to the forecasting.In this respect,new ANN models are proposed in this paper,which are developed by:varying the number of prior 1-h periods(periods prior to the forecasting hour)chosen for the input layer parameters;and/or incorporating in the input layer data from a second weather station in addition to the wind farm reference station.It has been found that the model performance is always improved when data from a second weather station are incorporated.The mean absolute relative error(MARE)of the new models is reduced by up to 7.5%.Furthermore,the longer the forecasting horizon,the greater the degree of improvement.Sergio Velázquez Medina Ulises Portero Ajenjo 2020Journal of Modern Power Systems and Clean Energy2020,8,3:6
5Gallstone ileus:One-stage surgery in a patient with intermittent obstruction显示文摘Gallstone ileus, an uncommon complication of cholelithiasis, is described as a mechanical intestinal obstruction due to impaction of one or more large gallstones within the gastrointestinal tract. The clinical presentation is variable, depending on the site of obstruction, manifested as acute, intermittent or chronic episodes. A 51-year-old female patient was referred to our hospital with 3 events of intestinal obstruction during the previous 7 d. At admission, there were clinical signs of intestinal obstruction; abdominal film demonstrated dilated bowel loops, air-fluid levels and a vague image of a stone in the inferior left quadrant. Once stabilized, a laparotomy was performed. Surgical findings were distention of the jejunum and ileum proximal to a palpable stone in the ileum as well as gallstones and a cholecystoduodenal fistula in the gallbladder. An enterolithotomy, repair of the cholecystoduodenal fistula and cholecystectomy were performed. The postoperative course was uneventful. There is no uniform surgical procedure for this disease. When the patient is too ill or when biliary surgery is not advisable, an enterolithotomy is the best option. The one-stage procedure should be the offered to adequately stabilized patients when local and general conditions, such as good cardiorespiratory and metabolic reserve permit a more prolonged surgical procedure.Carlos M Nuo-Guzmán José Arróniz-Jáuregui Pável A Moreno-Pérez édgar A Chávez-Solís Nereida Esparza-Arias Cuauhtémoc I Hernández-González 2010World Journal of Gastrointestinal Surgery2010,2,5:5
6Timing, method and discontinuation of hydrocortisone administration for septic shock patients显示文摘AIM To characterize the prescribing patterns for hydrocortisone for patients with septic shock and perform an exploratory analysis in order to identify the variables associated with better outcomes.METHODS This prospective cohort study included 59 patients with septic shock who received stress-dose hydrocortisone.It was performed at 2 critical care units in academic hospitals from June 1st, 2015, to July 31 st, 2016. Demographic data, comorbidities, medical management details, adverse effects related to corticosteroids, and outcomes were collected after the critical care physician indicated initiation of hydrocortisone. Univariate comparison between continuous and bolus administration of hydrocortisone was performed, including multivariate analysis, as well as Kaplan-Meier analysis to compare the proportion of shock reversal at 7 d after presentation. Receiver operating characteristic(ROC) curves determined the best cut-off criteria for initiation of hydrocortisone associated with the highest probability of shock reversal. We addressed the effects of the taper strategy for discontinuation of hydrocortisone, noting risk of shock relapse and adverse effects.RESULTS All-cause 30-d mortality was 42%. Hydrocortisone was administered as a continuous infusion in 54.2% of patients; time to reversal of shock was 49 h longer in patients who were given a bolus administration [59 h(range, 47.5-90.5) vs 108 h(range, 63.2-189); P = 0.001]. The maximal dose of norepinephrine after initiation of hydrocortisone was lower in patients on continuous infusion [0.19 μg/kg per minute(range, 0.11-0.28 μg)] compared with patients who were given bolus [0.34 μg/kg per minute(range, 0.16-0.49); P = 0.004]. Kaplan-Meier analysis revealed a higher proportion of shock reversal at 7 d in patients with continuous infusion compared to those given bolus(83% vs 63%; P = 0.004). There was a good correlation between time to initiation of hydrocortisone and time to reversal of shock(r = 0.80; P < 0.0001); ROC curve analysis revealed that the best criteria for prediction of shock reversal was a time to initiation of hydrocortisone of ≤ 13 h after administration of norepinephrine, with an area under the curve of 0.81(P < 0.001). The maximal dose of norepinephrine at initiation of hydrocortisone with the highest association with shock reversal was ≤ 0.28 μg/kg per minute, with an area under the curve of 0.75(P = 0.0002). On a logistic regression model, hydrocortisone taper was not associated with a lower risk of shock relapse(RR = 1.29; P = 0.17) but was related to a higher probability of hyperglycemia [odds ratio(OR), 5.3; P = 0.04] and hypokalemia(OR = 10.6; P = 0.01). CONCLUSION Continuous infusion of hydrocortisone could hasten the resolution of septic shock compared to bolus administration. Earlier initiation corresponds with a higher probability of shock reversal. Tapering strategy is unnecessary.Miguel A Ibarra-Estrada Quetzalcóatl Chávez-Pe?a Claudia I Reynoso-Estrella Jorge Rios-Zerme?o Pável E Aguilera-González Miguel A García-Soto Guadalupe Aguirre-Avalos 2017World Journal of Critical Care Medicine2017,6,1:4
7Tumor cells educate mesenchymal stromal cells to release chemoprotective and immunomodulatory factors显示文摘Factors released by surrounding cells such as cancer-associated mesenchymal stromal cells(CA-MSCs)are involved in tumor progression and chemoresistance.In this study,we characterize the mechanisms by which naYve mesenchymal stromal cells(MSCs)can acquire a CA-MSCs phenotype.Ovarian tumor cells trigger the transformation of MSCs to CA-MSCs by expressing pro-tumoral genes implicated in the chemoresistance of cancer cells,resulting in the secretion of high levels of CXC chemokine receptors 1 and 2(CXCR1/2)ligands such as chemokine(C-X-C motif)ligand 1(CXCL1),CXCL2,and interleukin 8(IL-8).CXCR1/2 ligands can also inhibit the immune response against ovarian tumor cells.Indeed,through their released factors,CA-MSCs promote the differentiation of monocytes towards M2 macrophages,which favors tumor progression.When CXCR1/2 receptors are inhibited,these CA-MSC-activated macrophages lose their M2 properties and acquire an anti-tumoral phenotype.Both ex vivo and in vivo,we used a CXCR1/2 inhibitor to sensitize ovarian tumor cells to carboplatin and circumvent the pro-tumoral effects of CA-MSCs.Since high concentrations of CXCR1/2 ligands in patients*blood are associated with chemoresistance,CXCR1/2 inhibition could be a potential therapeutic strategy to revert carboplatin resistance.Augustin Le Naour Melissa Prat Benolt Thibault Renaud Mével Léa Lemaitre Helene Leray Marie-Veronique Joubert Kimberley Coulson Muriel Golzio Lise Lefevre Eliane Mery Alejandra Martinez Gwénael Ferron Jean-Pierre Delord Agnès Coste Bettina Couderc 2020Journal of Molecular Cell Biology2020,12,3:3
8Cognitive disorder and dementia in type 2 diabetes mellitus显示文摘Insulin,a key pleiotropic hormone,regulates metabolism through several signaling pathways in target tissues including skeletal muscle,liver,and brain.In the brain,insulin modulates learning and memory,and impaired insulin signaling is associated with metabolic dysregulation and neurodegenerative diseases.At the receptor level,in aging and Alzheimer’s disease(AD)models,the amount of insulin receptors and their functions are decreased.Clinical and animal model studies suggest that memory improvements are due to changes in insulin levels.Furthermore,diabetes mellitus(DM)and insulin resistance are associated with age-related cognitive decline,increased levels ofβ-amyloid peptide,phosphorylation of tau protein;oxidative stress,pro-inflammatory cytokine production and dyslipidemia. Recent evidence shows that deleting brain insulin receptors leads to mildobesity and insulin resistance without influencing brain size and apoptosis development.Conversely, deleting insulin-like growth factor 1 receptor (IGF-1R) affects brain size anddevelopment, and contributes to behavior changes. Insulin is synthesized locally in the brain andis released from the neurons. Here, we reviewed proposed pathophysiological hypotheses toexplain increased risk of dementia in the presence of DM. Regardless of the exact sequence ofevents leading to neurodegeneration, there is strong evidence that mitochondrial dysfunctionplays a key role in AD and DM. A triple transgenic mouse model of AD showed mitochondrialdysfunction, oxidative stress, and loss of synaptic integrity. These alterations are comparable tothose induced in wild-type mice treated with sucrose, which is consistent with the proposal thatmitochondrial alterations are associated with DM and contribute to AD development. Alterationsin insulin/IGF-1 signaling in DM could lead to mitochondrial dysfunction and low antioxidantcapacity of the cell. Thus, insulin/IGF-1 signaling is important for increased neural processing andsystemic metabolism, and could be a specific target for therapeutic strategies to decreasealterations associated with age-related cognitive decline.Genaro G Ortiz Miguel Huerta Héctor A González-Usigli Erandis D Torres-Sánchez Daniela LC Delgado-Lara Fermín P Pacheco-Moisés Mario A Mireles-Ramírez Blanca MG Torres-Mendoza Roxana I Moreno-Cih Irma E Velázquez-Brizuela 2022World Journal of Diabetes2022,13,4:2
9前列腺癌:ferumoxtran-10增强MRI对常规手术区外淋巴结转移的检出显示文摘目的前瞻性评价利用ferumoxtran-10进行增强MRI检查对前列腺癌病人常规盆腔淋巴结清扫区以外的淋巴结转移检出的可行性。方法该研究中4家医院都得到医院审查委员会批准,病人签署知情同意书。连续296例患前列腺癌并具有中至高度淋巴结转移风险(前列腺特异性抗原〉10ng/mL Gleason评分〉6,或分期为T3期)的病人(年龄47-83岁,平均67岁)纳入本研究。静脉注射ferumoxtran-10后24h进行MR淋巴结成像。在MR淋巴结成像中,阳性淋巴结是指常规淋巴结清扫区域(RDA)l以内或以外的淋巴结。依据MR淋巴结成像.进行了CT引导下活检、R.A.Heesakkers G.J.Jager A.M.Hvels B.de Hoop H.C.van den Bosch, F.Raat 刘丽华 2009国际医学放射学杂志2009,32,4:2
10Modifi cation of sleep architecture in an animal model of experimental cirrhosis显示文摘AIM: To analyze the polygraphic sleep patterns during cirrhosis progression in a rat model by repeated CCl4 administration. METHODS: Male Wistar rats received three weekly injections of CCl4 for 11 wk, and were analyzed before and during the induction of cirrhosis. Rats were implanted with electrodes to record their sleep patterns. Polygraph recordings were made weekly over 11 wk for 8 h, during the light period. After a basal recording, rats received three weekly injections of CCl4. Histological conf irmation of cirrhosis was performed after 11 wk.RESULTS: The results showed a progressive decrease in total wake time that reached statistical signif icance from the second week of treatment. In addition, there was an increase in total time of slow wave sleep (SWS) and rapid eye movement sleep (REM sleep) in most of the 11 wk. SWS showed no signif icant variations.During the final weeks, a significant increase in REM sleep frequency was also observed. Histological analyses of the livers showed unequivocal signs of cirrhosis. CONCLUSION: These data suggest that hepatic failure produced by CCl4 administration is capable of modifying the sleep pattern even after only a few doses.Anabel Jiménez-Anguiano Vanessa Díaz-Medina Blanca Eugenia Farfán-Labonne Gloria Giono-Chiang David Kersenobich Mario García-Lorenzana Maria Concepción Gutiérrez-Ruiz Javier Velázquez-Moctezuma 2009World Journal of Gastroenterology2009,15,41:2
11大型永磁同步电机在北欧国家的研究活动调查显示文摘本文概述了大型永磁同步电机在北欧国家的研究状况。研究发现,北欧国家在大型永磁同步电机的发展中处于领先地位。这主要得益于其悠久的造船传统,大型永磁同步电机的广泛应用及在风能转化方面的开拓。研究的焦点主要集中在运用径向磁通的永磁电机上,但最近几年,人们同样也把注意力集中在运用轴向及横向磁通的永磁电机上。大型永磁同步电机已开始在工业生产中得以应用,如ABB公司小型azipod中运用的径向磁通电机,Siemens公司的径向磁通潜艇发动机以及Jeumont在风力涡轮机中运用轴向磁通发电机。目前,欧洲大型电机生产商在他们多种多样的产品中运用径向磁通的同时正在开发轴向磁通技术,而较小且更专业的公司在他们的应用中研发出了轴向磁通电机。Kr Vel R. Nilssen A. Nysveen 赵东阳(翻译) 2009电器工业2009,,5:2
12Regeneration of neurotransmission transcriptome in a model of epileptic encephalopathy after antiinflammatory treatment显示文摘Inflammation is an established etiopathogenesis factor of infantile spasms(IS), a therapy-resistant epileptic syndrome of infancy. We investigated the IS-associated transcriptomic alterations of neurotransmission in rat hypothalamic arcuate nucleus, how they are corrected by antiinflamatory treatments and whether there are sex differences. IS was triggered by repeated intraperitoneal administration of N-methyl-D-aspartic acid following anti-inflammatory treatment(adreno-cortico-tropic-hormone(ACTH) or PMX53)or normal saline vehicle to prenatally exposed to betamethasone young rats. We found that treatments with both ACTH and PMX53 resulted in substantial recovery of the genomic fabrics of all types of synaptic transmission altered by IS. While ACTH represents the first line of treatment for IS, the even higher efficiency of PMX53(an antagonist of the complement C5 a receptor) in restoring the normal transcriptome was not expected. In addition to the childhood epilepsy, the recovery of the neurotransmission genomic fabrics by PMX53 also gives hope for the autism spectrum disorders that share a high comorbidity with IS. Our results revealed significant sex dichotomy in both IS-associated transcriptomic alterations(males more affected) and in the efficiency of PMX53 anti-inflammatory treatment(better for males). Our data further suggest that anti-inflammatory treatments correcting alterations in the inflammatory transcriptome may become successful therapies for refractory epilepsies.Dumitru A.Iacobas Libor Velísek 2018Neural Regeneration Research2018,13,10:2
13Few-mode fibre-optic microwave photonic links显示文摘The fibre-optic microwave photonic link has become one of the basic building blocks for microwave photonics.Increasing the optical power at the receiver is the best way to improve all link performance metrics including gain,noise figure and dynamic range.Even though lasers can produce and photodetectors can receive optical powers on the order of a Watt or more,the power-handling capability of optical fibres is orders-of-magnitude lower.In this paper,we propose and demonstrate the use of few-mode fibres to bridge this power-handling gap,exploiting their unique features of small acousto-optic effective area,large effective areas of optical modes,as well as orthogonality and walk-off among spatial modes.Using specially designed few-mode fibres,we demonstrate order-of-magnitude improvements in link performances for single-channel and multiplexed transmission.This work represents the first step in few-mode microwave photonics.The spatial degrees of freedom can also offer other functionalities such as large,tunable delays based on modal dispersion and wavelength-independent lossless signal combining,which are indispensable in microwave photonics.He Wen Hongjun Zheng Qi Mo Amado Manuel Velázquez-Benítez Cen Xia Bin Huang Huiyuan Liu Huang Yu Pierre Sillard Jose Enrique Antonio Lopez Rodrigo Amezcua Correa Guifang Li 2017Light(Science & Applications)2017,6,1:2
14Markov chain modelling of pitting corrosion in underground pipelines显示文摘F. Caleyo J.C. Velázquez A. Valor J.M. Hallen 2009Corrosion Science2009,,9:2
15Pain management in mice using methanol extracts of three plants belongs to family Amaranthaceae显示文摘Objective:To investigate the analgesic activity of methanolic extract of Amaranthus viridis(A. viridis),Amaranthus caudatus(A.caudatus) and Amaranthus spinosus(A.spinosus).Methods:In this study,the analgesic activity of methanol extracts of all three plants at doses of 200 and 400 mg/kg were investigated by acetic acid-induced writhings test,hot plate test and tail immersion test for mice.Results:It was found that all the three plants showed significant pain management effect(P<0.01) at a dose of 400 mg/kg,but showed a less significant effect at a dose of 20 mg/kg in the entire tests used for evaluation of analgesic activities(P<0.05).Conclusions:Methanol extracts of A.viridis,A.caudatus and A.spinosus show potent analgesic activities,and this study provides the scientific proof for their traditional claims.Ashok Kumar BS Lakshman K Jayaveera KN Vel Murgan C Arun Kumar PA Vinod Kumar R Meghda Hegade Sridhar SM 2010Asian Pacific Journal of Tropical Medicine2010,3,7:2
16Methyl tert-butyl ether biodegradation by microbial consortia obtained from soil samples of gasoline-polluted sites in Mexico显示文摘Marcia Morales Elia Velázquez Janet Jan Sergio Revah Uriel González Elías Razo-Flores 2004Biotechnology Letters2004,,4:1
17Business Model Innovation through Trial- and- Error Learning: The Naturhouse Case 显示文摘SOSNA M TREVINYORODNGUEZ R N VEL AMURI S R 2010Long Range Planning2010,43,23:1
18Cyto-kine and acute phase protein gene expression in repeat-ed liver biopsies of dairy cows with a lipopolysaccha-ride-induced mastitis 显示文摘VELS L R0NTVED C M BJERRING M 2009Journal of Dairy Science2009,92,3:1
19Evaluation of seven housekeeping genes for multilocus sequence analysis of the genus Mesorhizobium : resolving the taxonomic affiliation of the Cicer canariense rhizobia显示文摘Juan Pérez-Yépez Natalia Armas-Capote Encarna Velázquez Ricardo Pérez-Galdona Raúl Rivas Milagros León-Barrios 2014Systematic and Applied Microbiology2014,,:1
20Sensory, microbial and chemical effects of a slurry ice system on horse mackerel (Trachurus trachurus)显示文摘óscarRodríguez VanesaLosada Santiago PAubourg JorgeBarros‐Velázquez 2004Food Agric2004,,2:1
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