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Implications of denitrification in the ecological status of an urban river using enzymatic activities in sediments as an indicator

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Journal of Environmental Sciences 2019年第1期31卷 255-268页

作者： Jessica Unda-Calvo Miren Martínez-Santos Estilita Ruiz-Romera juan luis Lechuga-Crespo Department of Chemical and Environmental Engineering University of the Basque Country

A better understanding of the effects of a number of environmental factors on denitrification is vital for analyzing its role as nitrogen sink and providing deeper knowledge about the ecological status of a nitrate-rich ecosystem. Since few studies have addressed the occurrence and implications of denitrification in river sediments, and complexity of interactions among all these environmental factors makes comprehension of the process difficult, the potential of sediments from the Deba River to attenuate nitrate excess through denitrification was investigated. For this purpose, we adapted an in vitro method to measure activities of two enzymes contributing to the entire multiple-step nitrate reduction: Nitrate Reductase and Nitrite Reductase. The environmental features that influence both or single enzymatic activities were identified as oxygen availability,regulated directly by the moisture content or indirectly through the aerobic respiration,organic matter and nitrate content of sediments, and electrical conductivity and exchangeable sodium percentage of water. Additionally, our results showed that Nitrate Reductase catalyzes the principal limiting step of denitrification in sediments. Therefore,taking this enzymatic activity as an indicator, the southern part of the Deba River catchment presented low potential to denitrify but nitrate-limited sediments, whereas the middle and northern parts were characterized by high denitrification potential but nitraterich sediments. In general, this study on denitrifying enzymatic activities in sediments evaluates the suitability of the management of the effluents from wastewater treatment plants and municipal sewages to ensure a good ecological status of the Deba River.

关键词： Urban catchment Sediments Denitrification Enzymatic activity Ecological status

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Proline and Oxidative Metabolism in Young Pecan Trees Associated with Sulphate Accumulation

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Phyton-International Journal of Experimental Botany 2022年第6期91卷 1141-1152页

作者： Dalila Jacqueline Escudero-Almanza Oscar Cruz-Alvarez Ofelia Adriana Hernández-Rodríguez juan luis Jacobo-Cuellar Esteban Sánchez-Chávez Pablo Preciado-Rángel Dámaris Leopoldina Ojeda-Barrios Facultad de Ciencias Agrotecnológicas Universidad Autónoma de ChihuahuaChihuahua31350México Centro de Investigación en Alimentación y Desarrollo A.C.Delicias33088México Institutotecnologico Nacional de México-Instituto tecnológico de Torreón Coahuila27170México

Pecan[Carya illinoinensis(Wangenh.)***.]is a deciduous tree whose fruits(nuts)are of high economic value and offer excellent nutritional ***,soils high in sulphates can limit its growth and *** with 5-year-old trees of‘Western Schley’pecan grown in soils high in sulphates,the levels of proline and oxidative metabolism were recorded in the *** showed that different levels of visible leaflet damage(‘sufficiency’,‘low’,‘moderate’or‘severe’)were associated with different levels of leaflet sulphates(mg kg^(−1)):‘sufficiency’(≤40),‘low’(41–60),‘moderate’(61–80)and‘severe’(80–100).‘Severe’sulphate damage was associated with significant reductions in chlorophyll(TChl)(17.04μg g^(−1)),relative water content(RWC)(50%)and leaf area(LA),and with increases in the concentrations of total carotenoids(TC)and proline(Prl).Increases were also observed in the activities of the oxidative metabolism enzymes:superoxide dismutase(SOD)(1.82 units min^(−1) g^(−1)),catalase(CAT)(2.86μmol H_(2)O_(2) min^(−1) g^(−1))and antioxidant capacity(AC)(87%DPPH inhibition).However,guaiacol peroxidase(GP)showed a reduction(2.97 nmol GSH min^(−1) g^(−1)).An inverse relationship was found between the sulphate concentration in the leaflets with respect to the evaluated parameters of TChl,TC,RWC,LA,AC,and *** synthesis and antioxidant enzymatic activity indicate salt stress in pecan leaflets in orchards irrigated with deep-well water high in sulphates.

关键词： Carya illinoinensis catalase guaiacol peroxidase salt stress photosynthetic pigments superoxide dismutase

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COVID-19 and Indirect Liver Injury:A Narrative Synthesis of the Evidence

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Journal of Clinical and Translational Hepatology 2021年第5期9卷 760-768页

作者： Francisco Idalsoaga Gustavo Ayares juan Pablo Arab luis Antonio Díaz Departamento de Gastroenterología Escuela de MedicinaPontificia Universidad Católica de ChileSantiagoChile Centro de Envejecimiento y Regeneración(CARE) Facultad de Ciencias BiológicasPontificia Universidad Católica de ChileSantiagoChile

The liver is frequently affected by severe acute respiratory syndrome-coronavirus 2(SARS-CoV-2)*** most common manifestations are mildly elevated alanine aminotransferase and aspartate aminotransferase,with a prevalence of 16-53%among *** with severe coronavirus disease 2019(COVID-19)seem to have higher rates of acute liver dysfunction,and the presence of abnormal liver tests at admission signifies a higher risk of severe disease during *** with chronic liver diseases also have a higher risk of severe disease and mortality(mainly seen in patients with metabolic-associated fatty liver disease).Several pathways of damage have been proposed in the liver involvement of COVID-19 patients;although,the end-cause is most likely *** liver tests have been attributed to the expression of angiotensin-converting enzyme 2 receptors in SARS-CoV-2 *** enzyme is expressed widely in cholangiocytes and less in *** factors attributed to liver damage include drug-induced liver injury,uncontrolled release of proinflammatory molecules(“cytokine storm”),pneumonia-associated hypoxia,and direct damage by the *** steatosis,vascular thrombosis,fibrosis,and inflammatory features(including Kupffer cell hyperplasia)are the most common liver histopathological findings in deceased COVID-19 patients,suggesting important indirect mechanisms of liver *** this translational medicinebased narrative review,we summarize the current data on the possible indirect mechanisms involved in liver damage due to COVID-19,the histopathological findings,and the impact of these mechanisms in patients with chronic liver disease.

关键词： COVID-19 SARS-CoV-2 Liver hepatitis Liver injury Novel coronavirus

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Electrochemical and spectroscopic study of interfacial interactions between chalcopyrite and typical flotation process reagents

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International Journal of Minerals,Metallurgy and Materials 2016年第2期23卷 127-136页

作者： Gustavo Urbano Isabel Lázaro Israel Rodríguez juan luis Reyes Roxana Larios Roel Cruz Instituto de Metalurgia Universidad Autonotrla de San Luis PotosiAvSierra Leona 550Lomas 2a SeccionSan Luis PotosiS.L.P.78210Mexico Industrial Minera Mexico S.A.de C.V. San Luis PotosiS.L.P.Mexico Centro Universitario de Ciencias Exactas e Ingenierias Universidad de GuadalajaraGuadalajaraJaliscoMexico

Comparative voltammetry and differential double-layer capacitance studies were performed to evaluate interfacial interactions between cnalcopyrite（CuFeS2） and n-isopropyl xanthate（X） in the presence of ammonium bisulfite/39wt%SO2 and caustic starch at different pH *** spectroscopy,Fourier transform infrared（FTIR） spectroscopy,contact angle measurements,and microflotation tests were used to establish the type and extent of xanthate adsorption as well as the species involved under different mineral surface conditions in this *** results demonstrate that the species that favor a greater hydrophobicity of chalcopyrite are primarily CuX and S^0,whereas oxides and hydroxides of Cu and Fe as well as an excess of starch decrease the hydrophobicity.A conditioning of the mineral surface with ammonium bisulfite/39wt%SO2 at pH 6 promotes the activation of surface and enhances the xanthate ***,this effect is diminished at pH ≥ 8,when an excess of starch is added during the preconditioning step.

关键词： sulfide minerals chalcopyrite xanthates flotation interfacial reactions electrochemistry spectroscopy

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Visual perception alterations in COVID-19:a preliminary study

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International Journal of Ophthalmology(English edition) 2023年第1期16卷 1-9页

作者： María Begoña Coco-Martín luis Leal-Vega Irene Alcoceba-Herrero Ainhoa Molina-Martín Dolores de-Fez María JoséLuque Carlos Dueñas-Gutiérrez juan Francisco Arenillas-Lara David PPiñero Group of Applied Clinical Neurosciences and Advanced Data Analysis Department of MedicineDermatology and ToxicologyUniversity of ValladolidValladolid 47005Spain Group of Optics and Visual Perception Department of OpticsPharmacology and AnatomyUniversity of AlicanteAlicante 03690Spain Department of Optics and Optometry and Vision SciencesUniversity of ValenciaValencia 46100Spain COVID-19 Unit Department of Internal MedicineUniversity Clinical Hospital of ValladolidValladolid 47003Spain Stroke Unit Department of NeurologyUniversity Clinical Hospital of ValladolidValladolid 47003Spain Clinical Optometry Unit Department of OphthalmologyVithas Medimar International HospitalAlicante 03016Spain

AIM:To compare the visual perception(color and chromatic-achromatic contrast vision)of a small cohort of COVID-19 patients at the time of infection and after 6mo with that of a healthy population matched for sex and ***:A total of 25 patients(9 females,16 males,mean age:54±10y)with COVID-19 hospitalized in the COVID-19 Unit of the University Clinical Hospital of Valladolid were recruited for this preliminary *** perception,as determined by monocular measurement of contrast sensitivity function(CSF)and color vision was assessed in each patient using the Optopad *** results obtained were then compared with those of a sample of 16 age-and sex-matched healthy controls(5 females,11 males,mean age:50±6y)in which the same measurement procedure was *** significant differences between groups were assessed using the Mann-Whitney U *** were repeated after a minimum follow-up period of 6mo and statistically significant differences between the two time points in each group were assessed using the Wilcoxon signed rank ***:Discrimination thresholds(color and chromatic-achromatic contrast vision)and their corresponding sensitivity,calculated as the inverse of the discrimination threshold,were *** of the data revealed higher contrast threshold results(i.e.,worse contrast sensitivity)in the COVID-19 group than in the control group for all spatial frequencies studied in the Optopad-CSF achromatic test and most of the spatial frequencies studied in the Optopad-CSF chromatic test for the red-green and blue-yellow *** addition,color threshold results in the COVID-19 group were also significantly higher(i.e.,worse color sensitivity)for almost all color mechanisms studied in the Optopad-Color *** 6mo,most of the differences found between the groups were maintained despite COVID-19 ***:The present results provide preliminary evidence that visual perception may be impaired in COVID-19

关键词： SARS-CoV-2 COVID-19 visual perception contrast sensitivity function color vision

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Survival after curative pancreaticoduodenectomy for ampullary adenocarcinoma in a South American population:A retrospective cohort study

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World Journal of Gastrointestinal Surgery 2022年第1期14卷 24-35页

作者： Ramiro Manuel Fernandez-Placencia Paola Montenegro Melvy Guerrero Mariana Serrano Emperatriz Ortega Mercedes Bravo Lourdes Huanca Stéphane Bertani juan Manuel Trejo Patricia Webb Jenny Malca-Vasquez luis Taxa Alberto Lachos-Davila juan Celis-Zapata Carlos Luque-Vasquez Eduardo Payet Eloy Ruiz Francisco Berrospi Hepato-Pancreato-Biliary Section Department of Abdominal SurgeryInstituto Nacional de Enfermedades NeoplasicasLima 15038Peru Department of Medical Oncology Instituto Nacional de Enfermedades NeoplasicasLima 15038Peru Department of Pathology Instituto Nacional de Enfermedades NeoplasicasLima 15038Peru International Joint Laboratory of Molecular Anthopological Oncology Instituto Nacional de Enfermedades NeoplasicasLima 15038Peru Unite Pharmacochim&Pharmacol Dev UMR152F-31062 ToulouseFrance Department of Radiation Oncology Instituto Nacional de Enfermedades NeoplasicasLima 15038Peru Department of Abdominal Surgery Instituto Nacional de Enfermedades NeoplasicasLima 15038Peru

BACKGROUND Ampullary adenocarcinoma(AAC)is a rare neoplasm that accounts for only 0.2%of all gastrointestinal *** incidence rate is lower than 6 cases per million *** prognostic factors have been described for AAC and are associated with a wide range of survival ***,these studies have been exclusively conducted in patients originating from Asian,European,and North American *** To evaluate the histopathologic predictors of overall survival(OS)in South American patients with AAC treated with curative pancreaticoduodenectomy(PD).METHODS We analyzed retrospective data from 83 AAC patients who underwent curative(R0)PD at the National Cancer Institute of Peru between January 2010 and October 2020 to identify histopathologic predictors of *** Sixty-nine percent of patients had developed intestinal-type AAC(69%),23%had pancreatobiliary-type AAC,and 8%had other ***-one percent of patients were classified as Stage I,according to the AJCC 8 th *** occurred primarily in the liver(n=8),peritoneum(n=4),and lung(n=4).Statistical analyses indicated that T3 tumour stage[hazard ratio(HR)of 6.4,95%confidence interval(CI)of 2.5-16.3,Ptended tumour stage(T3),pancreatobiliary type,and positive lymph node metastasis represent independent predictors of a lower OS rate in South American AAC patients who underwent curative PD.

关键词： Gastrointestinal neoplasms Adenocarcinoma Ampulla Pancreaticoduodenectomy Survival South America

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the 20GD Superfamily： Emerging Functions in Plant Epigenetics and Hormone Metabolism

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Molecular Plant 2018年第10期11卷 1222-1224页

作者： Riad Nadi Eduardo Mateo-Bonmati Lucia juan-Vicente Jose luis Micol Instituto de Bioingenieria Universidad Miguel Hern&ndez Campus de Elche 03202 Elche Spain

The 2-oxoglutarate and Fe （ll）-dependent dioxygenase （2OGD） superfamily includes oxidative enzymes with an active site con- taining two histidines and （in most cases） one aspartic or glutamic acid residue. This conserved motif is termed the 2-His-1-carboxylate facial triad, chelates iron, and is housed within a double-stranded β-helix fold, also known as the DSBH, jelly-roll, cupin, or Jumonji C fold （Martinez and Hausinger, 2015）. The reactions catalyzed by 2OGDs （also called 2ODDs, 2ODQs, and 2OGXs） include but are not limited to demethylation, demethylenation, hydroxytation, halogenation, desaturation, ring cleavage, ring closure, and epimerization （Farrow and Facchini, 2014）.

关键词： DEMETHYLASE DIVERSITY

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Comparison of biological fitness in crosses between subspecies of Meccus phyllosomus （Hemiptera： Reduviidae： Triatominae） in southern Mexico

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Insect Science 2017年第1期24卷 114-121页

作者： Jose Alejandro Martinez-Ibarra Benjamin Nogueda-Torres luis Fernando Salazar-Montano juan Carlos Garcia-Lino Demver Arroyo-Reyes juan Angel Hernandez-Navarro Area de Entomologia Medica Universidad de Guadalajara Ciudad Guzman Jalisco Mexico Becario de COFAA Escuela Nacional de Ciencias Biologicas Instituto Politecnico Nacional D.F. Mexico Carrera de Medicina Departamento de Salud y Bienestar Centro Universitario del Sur Universidad de Guadalajara Ciudad Guzman Jalisco Mexico

Understanding the biological parameters of some triatomine subspecies of Meccus phyllosomus （Burmeister） is a crucial first step in estimating the epidemiologie importance of this group. Biological parameters related to hatching, lifetime, number of blood meals to molt, percentage of females at the end of the cycle, number of laid eggs, and mortality for each instar of 3 M. phyllosomus subspecies [M. p. mazzottii （Usinger）, M. p. pallidipennis （Stal）, and M. p. phyllosomus] and their laboratory hybrids were evaluated and compared. No significant differences （P 〉 0.05） were found among the experimental hybrids （MaPa, MaPhy, PaPhy） and reciprocal cohorts. In 5 （hatching, number of blood meals to molt, accumulative mortality, percentage of females, and mean number of laid eggs） of the 6 studied parameters （with the exception of development time）, the hybrid cohorts had better fitness results than the parental cohorts involved in each set of crosses. The increase in hybrid fitness found in our study could lead to an increase in the epidemiologic risks caused by transmission of Trypanosoma cruzi to humans.

关键词： biological parameters Chagas disease Meccus subspecies Mexico tri- atomines Trypanosoma cruzi transmission

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Increased DNA binding activity of NF-κB,STAT-3,SMAD3 and AP-1 in acutely damaged liver

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World Journal of Gastroenterology 2006年第37期12卷 5995-6001页

作者： Adriana Salazar-Montes luis Ruiz-Corro Ana Sandoval-Rodriguez Alberto Lopez-Reyes juan Armendariz-Borunda Institute of Molecular Biology in Medicine and Gene Therapy CUCS University of Guadalajara Apdo. Postal 2-123 Guadalajara 44281 Jal Mexico Institute of Molecular Biology in Medicine and Gene Therapy CUCS University of Guadalajara Apdo.Postal 2-123 Guadalajara 44281 Jal Mexico OPD Hospital Civil de Guadalajara Guadalajara Jal Mexico

AIM: To investigate the role of genes and kinetics of specific transcription factors in liver regeneration, and to analyze the gene expression and the activity of some molecules crucially involved in hepatic regeneration. METHODS: USING gel-shift assay and RT-PCR, transcription factors, such as NF-κB, STAT-3, SMAD3 and AP-1, and gene expression of inducible nitric oxide synthase (iNOS), hepatocyte growth factor (HGF) and c-met were analyzed in an animal model of chemically induced hepatectomy. RESULTS: Gene expression of HGF and its receptor c-met peaked at 3 h and 24 h after acute CCl4 intoxi- cation. iNOS expression was only observed from 6 to 48 h. Transcriptional factor NF-κB had an early activation at 30 min after acute liver damage. STAT-3 peaked 3 h post- intoxication, while AP-1 displayed a peak of activation at 48 h. SMAD3 showed a high activity at all analyzed times. CONCLUSION: TNF-α and IL-6 play a central role in hepatic regeneration. These two molecules are responsible for triggering the cascade of events and switch-on of genes involved in cell proliferation, such as growth factors, kinases and cyclins which are direct participants of cell proliferation.

关键词： NF-κB STAT-3 SMAD3 AP-1 肝疾病基因表达病理机制

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Experience with the surgical treatment of hepatic hydatidosis: Case series with follow-up

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World Journal of Gastroenterology 2010年第26期16卷 3305-3309页

作者： Hector Losada Morales luis Burgos San juan Jorge Silva Abarca Cesar Muoz Castro Department of Surgery Universidad de La Frontera Hepato Pancreatic and Biliary Surgery Hospital Hernán Henríquez Aravena Department of Surgery Clínica Alemana de Temuco

AIM: To describe patient characteristics and the results of surgical treatment for hepatic hydatidosis (HH) in the Hospital Hernán Henríquez Aravena from December 2001 to March 2005. METHODS: Subjects older than 16 years with suspected HH were included based on the clinical picture and radiological studies. Variables examined included clinical and laboratory aspects, outcome, features of the parasite and surgical aspects. Descriptive statistics were used, calculating central tendency, dispersion and extreme tendency. RESULTS: The series was comprised of 122 patients, with an average age of 44 ± 16.9 years. The most frequently used surgical technique was subtotal cys-tectomy in 90% of the patients, followed by hepatic resection (hepatectomy, segmentectomy and subsegmentectomy) in 5%. In 2%, a combination of subtotal cystectomy and segmentectomy was performed. In addition, 28% of the series presented complications in the postoperative period and mortality was 2%. CONCLUSION: The most frequently used surgical technique for HH was subtotal cystectomy and the morbidity and mortality rates in this Chilean series are comparable to other national and international series.

关键词： Echinococcosis of liver Surgery Cases series Mortality Morbidity

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