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| 1 | Myocardial reperfusion injury and oxidative stress: Therapeutic opportunities显示文摘Acute myocardial infarction(AMI) is the leading cause of death worldwide. Its associated mortality, morbidity and complications have significantly decreased with the development of interventional cardiology and percutaneous coronary angioplasty(PCA) treatment, which quick-ly and effectively restore the blood flow to the area previously subjected to ischemia. Paradoxi-cally, the restoration of blood flow to the ischemic zone leads to a massive production of reactive oxygen species(ROS) which generate rapid and severe damage to biomolecules, generating a phenomenon called myocardial reperfusion injury(MRI). In the clinical setting, MRI is associated with multiple complications such as lethal reperfusion, no-reflow, myocardial stunning, and reperfusion arrhythmias. Despite significant advances in the understanding of the mechanisms accounting for the myocardial ischemia reperfusion injury, it remains an unsolved problem. Although promising results have been obtained in experimental studies(mainly in animal models), these benefits have not been translated into clinical settings. Thus, clinical trials have failed to find benefits from any therapy to prevent MRI. There is major evidence with respect to the contribution of oxidative stress to MRI in cardiovascular diseases. The lack- of consistency between basic studies and clinical trials is not solely based on the diversity inherent in epidemiology but is also a result of the methodological weak-nesses of some studies. It is quite possible that pharmacological issues, such as doses, active ingredients, bioavailability, routes of administration, co-therapies, startup time of the drug intervention,and its continuity may also have some responsibility for the lack- of consistency between different studies. Furthermore, the administration of high ascorbate doses prior to reperfusion appears to be a safe and rational therapy against the development of oxidative damage associated with myocardial reperfusion. In addition, the association with N-acetylcysteine(a glutathione donor) and deferoxamine(an iron chelator) could improve the antioxidant cardioprotection by ascorbate, mak-ing it even more effective in preventing myocardial reperfusion damage associated with PCA following AMI. | Jaime González-Montero Roberto Brito Abraham IJ Gajardo Ramón Rodrigo | 2018 | World Journal of Cardiology2018，10，9： | 56 |
| 2 | Essential hypertension and oxidative stress:New insights显示文摘Essential hypertension is a highly prevalent pathological condition that is considered as one of the most relevant cardiovascular risk factors and is an important cause of morbidity and mortality around the world. Despite the fact that mechanisms underlying hypertension are not yet fully elucidated,a large amount of evidence shows that oxidative stress plays a central role in its pathophysiology. Oxidative stress can be defined as an imbalance between oxidant agents,such as superoxide anion,and antioxidant molecules,and leads to a decrease in nitric oxide bioavailability,which is the main factor responsible for maintaining the vascular tone. Several vasoconstrictor peptides,such as angiotensin Ⅱ,endothelin-1 and urotensin Ⅱ,act through their receptors to stimulate the production of reactive oxygen species,by activating enzymes like NADPH oxidase andxanthine oxidase. The knowledge of the mechanism described above has allowed generating new therapeutic strategies against hypertension based on the use of antioxidants agents,including vitamin C and E,N-Acetylcysteine,polyphenols and selenium,among others. These substances have different therapeutic targets,but all represent antioxidant reinforcement. Several clinical trials using antioxidants have been made. The aim of the present review is to provide new insights about the key role of oxidative stress in the pathophysiology of essential hypertension and new clinical attempts to demonstrate the usefulness of antioxidant therapy in the treatment of hypertension. | Jaime González Nicolás Valls Roberto Brito Ramón Rodrigo | 2014 | World Journal of Cardiology2014，6，6： | 20 |
| 3 | Non invasive blood flow measurement in cerebellum detects minimal hepatic encephalopathy earlier than psychometric tests显示文摘AIM: To assess whether non invasive blood flow measurement by arterial spin labeling in several brain regions detects minimal hepatic encephalopathy. METHODS: Blood flow(BF) was analyzed by arterial spin labeling(ASL) in different brain areas of 14 controls, 24 cirrhotic patients without and 16 cirrhotic patients with minimal hepatic encephalopathy(MHE). Images were collected using a 3 Tesla MR scanner(Achieva 3T-TX, Philips, Netherlands). Pulsed ASL was performed. Patients showing MHE were detected using the battery Psychometric Hepatic Encephalopathy Score(PHES) consisting of five tests. Different cognitive and motor functions were also assessed: alterations in selective attention were evaluated using the Stroop test. Patients and controls also performed visuo-motor and bimanual coordination tests. Several biochemical parameters were measured: serum pro-inflammatory interleukins(IL-6 and IL-18), 3-nitrotyrosine, cGMP and nitrates+nitrites in plasma, and blood ammonia. Bivariate correlations were evaluated.RESULTS: In patients with MHE, BF was increased in cerebellar hemisphere(P = 0.03) and vermis(P = 0.012) and reduced in occipital lobe(P = 0.017). BF in cerebellar hemisphere was also increased in patients without MHE(P = 0.02). Bimanual coordination was impaired in patients without MHE(P = 0.05) and much more in patients with MHE(P < 0.0001). Visuo-motor coordination was impaired only in patients with MHE(P < 0.0001). Attention was slightly affected in patients without MHE and more strongly in patients with MHE(P< 0.0001). BF in cerebellar hemisphere and vermis correlated with performance in most tests of PHES [(number connection tests A(NCT-A), B(NCT-B)and line tracing test] and in the congruent task of Stroop test. BF in frontal lobe correlated with NCT-A. Performance in bimanual and visuomotor coordination tests correlated only with BF in cerebellar hemisphere. BF in occipital lobe correlates with performance in the PHES battery and with CFF. BF in cerebellar hemisphere correlates with plasma cGMP and nitric oxide(NO) metabolites. BF in vermis cerebellar also correlates with NO metabolites and with 3-nitrotyrosine. IL-18 in plasma correlates with BF in thalamus and occipital lobe.CONCLUSION: Non invasive BF determination in cerebellum using ASL may detect MHE earlier than the PHES. Altered NO-cGMP pathway seems to be associated to altered BF in cerebellum. | Vicente Felipo Amparo Urios Carla Giménez-Garzó Omar Cauli Maria-Jesús Andrés-Costa Olga González Miguel A Serra Javier Sánchez-González Roberto Aliaga Remedios Giner-Durán Vicente Belloch Carmina Montoliu | 2014 | World Journal of Gastroenterology2014，20，33： | 12 |
| 4 | Management of nonalcoholic fatty liver disease:An evidence-based clinical practice review显示文摘AIM:To build a consensus among Chilean specialists on the appropriate management of patients with nonalcoholic fatty liver disease(NAFLD)in clinical practice.METHODS:NAFLD has now reached epidemic proportions worldwide.The optimal treatment for NAFLD has not been established due to a lack of evidence-based recommendations.An expert panel of members of the Chilean Gastroenterological Society and the Chilean Hepatology Association conducted a structured analysis of the current literature on NAFLD therapy.The quality of the evidence and the level of recommendations supporting each statement were assessed according to the recommendations of the United States Preventive Services Task Force.A modified three-round Delphi technique was used to reach a consensus among the experts.RESULTS:A group of thirteen experts was established.The survey included 17 open-ended questions that were distributed among the experts,who assessed the articles associated with each question.The levels of agreement achieved by the panel were 93.8%in the first round and 100%in the second and third rounds.The final recommendations support the indication of lifestyle changes,including diet and exercise,for all patients with NAFLD.Proven pharmacological therapies include only vitamin E and pioglitazone,which can be used in nondiabetic patients with biopsy-proven nonalcoholic steatohepatitis(the progressive form of NAFLD),although the long-term safety and efficacy of these therapies have not yet been established.CONCLUSION:Current NAFLD management is rapidly evolving,and new pathophysiology-based therapies are expected to be introduced in the near future.All NAFLD patients should be evaluated using a three-focused approach that considers the risks of liver disease,diabetes and cardiovascular events. | Juan P Arab Roberto Candia Rodrigo Zapata Cristián Mu?oz Juan P Arancibia Jaime Poniachik Alejandro Soza Francisco Fuster Javier Brahm Edgar Sanhueza Jorge Contreras M Carolina Cuellar Marco Arrese Arnoldo Riquelme | 2014 | World Journal of Gastroenterology2014，20，34： | 11 |
| 5 | Watch and wait approach in rectal cancer:Current controversies and future directions显示文摘According to the main international clinical guidelines,the recommended treatment for locally-advanced rectal cancer is neoadjuvant chemoradiotherapy followed by surgery.However,doubts have been raised about the appropriate definition of clinical complete response(cCR)after neoadjuvant therapy and the role of surgery in patients who achieve a cCR.Surgical resection is associated with significant morbidity and decreased quality of life(QoL),which is especially relevant given the favourable prognosis in this patient subset. Accordingly, therehas been a growing interest in alternative approaches with less morbidity,including the organ-preserving watch and wait strategy, in which surgery isomitted in patients who have achieved a cCR. These patients are managed with aspecific follow-up protocol to ensure adequate cancer control, including the earlyidentification of recurrent disease. However, there are several open questionsabout this strategy, including patient selection, the clinical and radiologicalcriteria to accurately determine cCR, the duration of neoadjuvant treatment, therole of dose intensification (chemotherapy and/or radiotherapy), optimal followupprotocols, and the future perspectives of this approach. In the present review,we summarize the available evidence on the watch and wait strategy in thisclinical scenario, including ongoing clinical trials, QoL in these patients, and thecontroversies surrounding this treatment approach. | Fernando López-Campos Margarita Martín-Martín Roberto Fornell-Pérez Juan Carlos García-Pérez Javier Die-Trill Raquel Fuentes-Mateos Sergio López-Durán JoséDomínguez-Rullán Reyes Ferreiro AlejandroRiquelme-Oliveira Asunción Hervás-Morón Felipe Couñago | 2020 | World Journal of Gastroenterology2020，26，29： | 10 |
| 6 | Portal vein thrombosis with protein C-S deficiency in a noncirrhotic patient显示文摘There are several conditions that can lead to portal vein thrombosis(PVT), including including infection, malignancies, and coagulation disorders. Anew condition of interest is protein C and S deficiencies, associated with hypercoagulation and recurrent venous thromboembolism. We report the case of a non-cirrhotic 63-year-old male diagnosed with acute superior mesenteric vein thrombosis and PVT and combined deficiencies in proteins C and S, recanalized by short-term low molecular heparin plus oral warfarin therapy. | Gustavo A Rodríguez-Leal Segundo Morán Roberto Corona-Cedillo Rocío Brom-Valladares | 2014 | World Journal of Hepatology2014，6，7： | 10 |
| 7 | Effect of phacoemulsification on intraocular pressure in patients with primary open angle glaucoma and pseudoexfoliation glaucoma显示文摘AIM: To compare the effect of phacoemulsification on intraocular pressure(IOP) in patients with primary open angle glaucoma(POAG) and pseudoexfoliation glaucoma(PXG). METHODS: A retrospective comparative case series conducted at the Glaucoma Department at the Association to Prevent Blindness in Mexico. The study enrolled consecutive patients having phacoemulsification with intraocular lens(IOL) implantation and a diagnosis of POAG or PXG. Data about IOP values and number of glaucoma medications used was collected at baseline, 1, 3, 6 and 12 mo postoperatively. RESULTS: The study enrolled 88 patients(88 eyes). After phacoemulsification, there was a statistically significant reduction in IOP values and glaucoma medications use compared to baseline in both POAG and PXG patients(P<0.001). In the POAG group, a 20% decrease in IOP values was evidenced, and a 56.5% reduction in the number of medications used at the one-year follow-up. The PXG group showed a 20.39%, and a 34.46% decrease in IOP and number of medications used, respectively. A significant difference in the mean ΔIOP(postoperative changes in IOP) was evidenced between groups(P=0.005). The reduction of the postsurgical IOP mean values in both groups, the POAG group showed a greater reduction in IOP values compared to the PXG group.CONCLUSION: In both types of glaucoma, phacoemulsification cataract surgery can result in a significant IOP reduction(20%) over a 12 mo follow-up period. The number of medications used is also significantly reduced up to 12 mo after surgery, especially in the PXG group. | Jesus Jimenez-Roman Gabriel Lazcano-Gomez Karina Martínez-Baez Mauricio Turati Rosario Gulías-Canizo Luis F.Hernández-Zimbrón Lenin Ochoa-De la Paz Rubén Zamora Roberto Gonzalez-Salinas | 2017 | International Journal of Ophthalmology(English edition)2017，10，9： | 7 |
| 8 | Enamel microabrasion: An overview of clinical and scientific considerations显示文摘Superficial stains and irregularities of the enamelare generally what prompt patients to seek dental intervention to improve their smile. These stains or defects may be due to hypoplasia, amelogenesis imperfecta, mineralized white spots, or fluorosis, for which enamel microabrasion is primarily indicated. Enamel microabrasion involves the use of acidic and abrasive agents, such as with 37% phosphoric acid and pumice or 6% hydrochloric acid and silica, applied to the altered enamel surface with mechanical pressure from a rubber cup coupled to a rotatory mandrel of a lowrotation micromotor. If necessary, this treatment can be safely combined with bleaching for better esthetic results. Recent studies show that microabrasion is a conservative treatment when the enamel wear is minimal and clinically imperceptible. The most important factor contributing to the success of enamel microabrasion is the depth of the defect, as deeper, opaque stains, such as those resulting from hypoplasia, cannot be resolved with microabrasion, and require a restorative approach. Surface enamel alterations that result from microabrasion, such as roughness and microhardness, are easily restored by saliva. Clinical studies support the efficacy and longevity of this safe and minimally invasive treatment. The present article presents the clinical and scientific aspects concerning the microabrasion technique, and discusses the indications for and effects of the treatment, including recent works describing microscopic and clinical evaluations. | Núbia Inocencya Pavesi Pini Daniel Sundfeld-Neto Flavio Henrique Baggio Aguiar Renato Herman Sundfeld Luis Roberto Marcondes Martins José Roberto Lovadino Débora Alves Nunes Leite Lima | 2015 | World Journal of Clinical Cases2015，3，1： | 6 |
| 9 | 通过手术导致的重量损失由胃绕过在疾病的肥胖的病人改进非含酒精的脂肪肝疾病显示文摘 AIM:To evaluate the effects of surgical weight loss(Roux-en-Y gastric bypass with a modified Fobi-Capella technique) on non alcoholic fatty liver disease in obese patients.METHODS:A group of 26 morbidly obese patients aged 45 ± 2 years and with a body mass index > 40 kg/m 2 who underwent open surgical weight loss operations had paired liver biopsies,the first at surgery and the second after 16 ± 3 mo of weight loss.Biopsies were evaluated and compared in a blinded fashion.The presence of metabolic syndrome,anthropometric and biochemical variables were also assessed at baseline and at the time of the second biopsy.RESULTS:Percentage of excess weight loss was 72.1% ± 6.6%.There was a reduction in prevalence of metabolic syndrome from 57.7%(15 patients) to 7.7%(2 patients)(P < 0.001).Any significance difference was observed in aspartate aminotransferase or alanine aminotransferase between pre and postsurgery.There were improvements in steatosis(P < 0.001),lobular(P < 0.001) and portal(P < 0.05) inflammation and fibrosis(P < 0.001) at the second biopsy.There were 25(96.1%) patients with non alcoholic steatohepatitis(NASH) in their index biopsy and only four(15.3%) of the repeat biopsies fulfilled the criteria for NASH.The persistence of fibrosis(F > 1) was present in five patients at second biopsy.Steatosis and fibrosis at surgery were predictors of significant fibrosis postsurgery.CONCLUSION:Restrictive mildly malabsorptive surgery provides significant weight loss,resolution of metabolic syndrome and associated abnormal liver histological features in most obese patients. | Víctor Vargas Helena Allende Albert Lecube Maria Teresa Salcedo Juan A Baena-Fustegueras José M Fort Joaquín Rivero Roser Ferrer Roberto Catalán Eva Pardina Santiago Ramón y Cajal Jaime Guardia Julia Peinado-Onsurbe | 2012 | World Journal of Hepatology2012，4，12： | 6 |
| 10 | Imatinib-induced fatal acute liver failure显示文摘Imatinib mesylate is a drug that has been approved for treatment of chronic myeloid leukemia (CML) in blast crisis, accelerated or chronic phase, and also for advanced gastrointestinal stromal tumors. Severe hepatic toxicity and three deaths from hepatic failure have been reported. We report the case of a 51-year-old woman who was admitted to our institution with severe acute hepatitis. She was diagnosed with CML and began treatment with imatinib mesylate at a dose of 400 mg/d. Five months after beginning treatment, she developed severe hepatitis associated with coagulopathy, and was admitted to our institution. She had been consuming acetaminophen 500-1000 mg/d after the onset of symptoms. She had a progressive increase in bilirubin level and a marked decrease of clotting factor Ⅴ. Five days after admission, grade Ⅱ encephalopathy developed and she was referred for liver transplantation. Her clinical condition progressively deteriorated, and 48 h after being referred for transplantation she suffered a cardiac arrest and died. This report adds concern about the possibility of imatinib-mesylate-induced hepatotoxicity and liver failure, particularly in the case of concomitant use with acetaminophen. Liver function tests should be carefully monitored during treatment and, with the appearance of any elevation of liver function tests, treatment should be discontinued. | Ezequiel Ridruejo Roberto Cacchione Alejandra G Villamil Sebastián Marciano Adrián C Gadano Oscar G Mandó | 2007 | World Journal of Gastroenterology2007，13，48： | 5 |
| 11 | Celiac disease serology in patients with different pretest probabilities: Is biopsy avoidable?显示文摘AIM: To establish the diagnostic performance of sev-eral serological tests, individually and in combination, for diagnosing celiac disease (CD) in patients with different pretest probabilities, and to explore potential se- rological algorithms to reduce the necessity for biopsy. METHODS: We prospectively performed duodenal biopsy and serology in 679 adults who had either high risk (n = 161) or low risk (n = 518) for CD. Blood samples were tested using six assays (enzyme-linked immunosorbent assay) that detected antibodies to tissue transglutaminase (tTG) and deamidated gliadin peptide (DGP). RESULTS: CD prevalence was 39.1% in the high-risk population and 3.3% in the low-risk group. In high-risk patients, all individual assays had a high diagnostic efficacy [area under receiving operator characteristic curves (AU ROC): 0.968 to 0.999]. In contrast, assays had a lower diagnostic efficacy (AU ROC: 0.835 to 0.972) in the low-risk group. Using assay combinations, it would be possible to reach or rule out diagnosis of CD without biopsy in 92% of cases in both pretest populations. We observed that the new DGP/tTG Screen assay resulted in a surplus compared to more conventional assays in any clinical situation. CONCLUSION: The DGP/tTG Screen assay could be considered as the best initial test for CD. Combinations of two tests, including a DGP/tTG Screen, might be able to diagnose CD accurately in different clinical scenarios making biopsy avoidable in a high proportion of subjects. | Emilia Sugai María L Moreno Hui J Hwang Ana Cabanne Adriana Crivelli Fabio Nach-man Horacio Vázquez Sonia Niveloni Julio Argonz Roberto Mazure Graciela La Motta María E Caniggia Edgardo Smecuol Néstor Chopita Juan C Gómez Eduardo Maurińo Julio C Bai | 2010 | World Journal of Gastroenterology2010，16，25： | 4 |
| 12 | Role of the HLA-DQ locus in the development of chronic gastritis and gastric carcinoma in Mexican patients显示文摘AIM: To determine the HLA-DQ locus in Mexican patients with Chronic gastritis and gastric adenocarcinoma. METHODS: Oligotyping for HLA-DQ locus was performed in 45 Mexican patients with chronic gastritis and 13 Mexican patients with diffuse-type gastric adenocarcinoma, and was then compared with 99 clinically healthy unrelated individuals. H pylori infection and CagA status were assessed in patients by enzyme-linked immunosor-bent assay (ELISA) method. RESULTS: We found a significant increased frequency of HLA-DQB1*0401 allele in H pylori-positive patients with chronic gastritis when compared with healthy subjects [19 vs 0%, P= 1 × 10-7, odds ratio (OR) = 4.96; 95% confidence interval (95% CI), 3.87-6.35]. We also found a significant increased frequency of HLA-DQB1*0501 in patients with diffuse-type gastric carcinoma in comparison with healthy individuals (P = 1 × 10-6, OR = 13.07; 95% CI, 2.82-85.14). CONCLUSION: HLA-DQ locus may play a different role in the development of H pylori-related chronic gastritis and diffuse-type gastric adenocarcinoma in the Mexican Mestizo population. | Roberto Herrera-Goepfert Jesús K Yamamoto-Furusho Luis F Oate-Ocaa Margarita Camorlinga-Ponce Leopoldo Muoz Jorge A Ruiz-Morales Gilberto Vargas-Alarcón Julio Granados Cellular Biology Section | 2006 | World Journal of Gastroenterology2006，12，48： | 4 |
| 13 | Immunohistochemical expression of intrarenal renin angiotensin system components in response to tempol in rats fed a high salt diet显示文摘AIM To determine the effect of tempol in normal rats fed high salt on arterial pressure and the balance between antagonist components of the renal renin-angiotensin system.METHODS Sprague-Dawley rats were fed with 8% Na Cl highsalt(HS) or 0.4% Na Cl(normal-salt,NS) diet for 3 wk,with or without tempol(T)(1 mmol/L,administered in drinking water). Mean arterial pressure(MAP),glomerularfiltration rate(GFR),and urinary sodium excretion(UVNa) were measured. We evaluated angiotensin Ⅱ(Ang Ⅱ),angiotensin 1-7(Ang 1-7),angiotensin converting enzyme 2(ACE2),mas receptor(Mas R),angiotensin type 1 receptor(AT1R) and angiotensin type 2 receptor(AT2R) in renal tissues by immunohistochemistry.RESULTS The intake of high sodium produced a slight but significant increase in MAP and differentially regulated components of the renal renin-angiotensin system(RAS). This included an increase in Ang Ⅱ and AT1 R,and decrease in ACE-2 staining intensity using immunohistochemistry. Antioxidant supplementation with tempol increased natriuresis and GFR,prevented changes in blood pressure and reversed the imbalance of renal RAS components. This includes a decrease in Ang Ⅱ and AT1 R,as increase in AT2,ACE2,Ang(1-7) and Mas R staining intensity using immunohistochemistry. In addition,the natriuretic effects of tempol were observed in NS-T group,which showed an increased staining intensity of AT2,ACE2,Ang(1-7) and Mas R.CONCLUSION These findings suggest that a high salt diet leads to changes in the homeostasis and balance between opposing components of the renal RAS in hypertension to favour an increase in Ang Ⅱ. Chronic antioxidant supplementation can modulate the balance between the natriuretic and antinatriuretic components of the renal RAS. | Gabriel Cao Silvana Lorena Della Penna Nicolas Martín Kouyoumdzian Marcelo Roberto Choi Susana Gorzalczany Belisario Enrique Fernández Jorge Eduardo Toblli María Inés Roson | 2017 | World Journal of Nephrology2017，6，1： | 4 |
| 14 | Partial anterior cruciate ligament tears treated with intraligamentary plasma rich in growth factors显示文摘AIM:To evaluate the effect of the application of plasma rich in growth factors(PRGF)-Endoret to the remaining intact bundle in partial anterior cruciate ligament(ACL)tears.METHODS:A retrospective review of the rate of return to play in football players treated with the application of PRGF-Endoret in the remaining intact bundle in partial ACL injuries that underwent surgery for knee instability.Patients with knee instability requiring revision surgery for remnant ACL were selected.PRGF was applied in the wider part of posterolateral bundle and the time it took patients to return to their full sporting activities at the same level before the injury was evaluated.RESULTS:A total of 19 patients were reviewed.Three had a Tegner activity level of 10 and the remaining 16level 9.The time between the injury and the time of surgery was 5.78 wk(SD 1.57).In total,81.75%(16/19)returned to the same pre-injury level of sport activity(Tegner 9-10).17 males and 2 females were treated.The rate of associated injury was 68.42%meniscal lesions and 26.31%cartilage lesions.The KT-1000 values were normalized in all operated cases.One patient was not able to return to sport due to the extent of their cartilage lesions.The 15 patients with Tegner activity level 9 returned to play at an average of 16.20 wk(SD1.44)while the 3 patients with Tegner activity level 10did so in 12.33 wk(SD 1.11).CONCLUSION:With one remaining intact bundle the application of PRGF-Endoret in instability cases due to partial ACL tear showed high return to sport rates at pre-injury level in professional football players. | Roberto Seijas Oscar Ares Xavier Cuscó Pedro lvarez Gilbert Steinbacher Ramón Cugat | 2014 | World Journal of Orthopedics2014，5，3： | 3 |
| 15 | Wavelet-based deconvolution of ultrasonic signals in nondestructive evaluation显示文摘In this paper, the inverse problem of reconstructing reflectivity function of a medium is examined within a blind deconvolution framework. The ultrasound pulse is estimated using higher-order statistics, and Wiener filter is used to obtain the ultrasonic reflectivity function through wavelet-based models. A new approach to the parameter estimation of the inverse filtering step is proposed in the nondestructive evaluation field, which is based on the theory of Fourier-Wavelet regularized deconvolution (ForWaRD). This new approach can be viewed as a solution to the open problem of adaptation of the ForWaRD framework to perform the convolution kernel estimation and deconvolution interdependently. The results indicate stable solutions of the esti- mated pulse and an improvement in the radio-frequency (RF) signal taking into account its signal-to-noise ratio (SNR) and axial resolution. Simulations and experiments showed that the proposed approach can provide robust and optimal estimates of the reflectivity function. | HERRERA Roberto Henry OROZCO Rubén RODRIGUEZ Manuel | 2006 | Journal of Zhejiang University-Science A(Applied Physics & Engineering)2006，7，10： | 2 |
| 16 | Complex causes and consequences of rangeland greening in South America -multiple interacting natural and anthropogenic drivers and simultaneous ecosystem degradation and recovery trends显示文摘Land-surface greening has been reported globally over the past decades.While often seen to represent ecosystem recovery,the impacts on biodiversity and society can also be negative.Greening has been widely reported from rangelands,where drivers and processes are complex due to its high environmental heterogeneity and societal dynamics.Here,we assess the complexity behind greening and assess its links to various drivers in an iconic,heterogeneous rangeland area,the IberáWetlands and surroundings,in Argentina.Time-series satellite imagery over the past 19 years showed overall net greening,but also substantial local browning both in protected and unprotected areas,linking to land use,temporal changes in surface water,fire,and weather.We found substantial woody expansion mainly in the unprotected land,with 37%contributed by tree plantations and the remaining 63%by spontaneous woody expansion,along with widespread transitions from terrestrial land to seasonal surface water.Fire occurrences tended to reduce greening with unprotected areas experiencing widespread and frequent fire.However,protected areas had more browning in unburnt areas than burned areas.Temporal variation in annual precipitation and temperature tended to nonlinearly influence fire occurrences with an interplay of human fire management,further shaping the vegetation greening,pointing to high complexity behind the observed rangeland greening involving interactions among local drivers.Our findings highlight that the observed overall greening is an outcome of multiple trends with clear negative impacts on biodiversity and the local livestock-oriented culture(notably expanding tree plantations)and spontaneous vegetation dynamics,partly involving spontaneous woody expansion.The latter has positive potential for biodiversity and ecosystem services in terms of woodland recovery,but can become negative in such a natural savanna region if expansions develop on a too broad scale,highlighting the importance of ensuring recovery of natural fire and herbivory regimes in protected areas along with sustainable rangeland management elsewhere. | Wang Li Robert Buitenwerf Renata Nicora Chequín Javier Elias Florentín Roberto Manuel Salas Julia Carolina Mata Li Wang Zheng Niu Jens-Christian Svenning | 2020 | Geography and Sustainability2020，1，4： | 2 |
| 17 | Management of Helicobacter pylori infection in Latin America: A Delphi technique-based consensus显示文摘AIM: To optimize diagnosis and treatment guidelines for this geographic region, a panel of gastroenterologists, epidemiologists, and basic scientists carried out a structured evaluation of available literature.METHODS: Relevant questions were distributed among the experts, who generated draft statements for consideration by the entire panel. A modified three-round Delphi technique method was used to reach consensus. Critical input was also obtained from representatives of the concerned medical community. The quality of the evidence and level of recommendation supporting each statement was graded according to United States Preventive Services Task Force criteria.RESULTS: A group of ten experts was established. The survey included 15 open-ended questions that were distributed among the experts, who assessed the articles associated with each question. The levels of agreement achieved by the panel were 50% in the first round, 73.3% in the second round and 100% in the third round. Main consensus recommendations included:(1) when available, urea breath and stool antigen test(HpSA) should be used for non-invasive diagnosis;(2) detect and eradicate Helicobacter pylori(H. pylori) in all gastroscopy patients to decrease risk of peptic ulcer disease, prevent o retard progression in patients with preneoplastic lesions, and to prevent recurrence in patients treated for gastric cancer;(3) further investigate implementation issues and health outcomes of H. pylorieradication for primary prevention of gastric cancer in high-risk populations;(4) prescribe standard 14-d triple therapy or sequential therapy for first-line treatment;(5) routinely assess eradication success post-treatment in clinical settings; and(6) select second- and third-line therapies according to antibiotic susceptibility testing.CONCLUSION: These achievable steps toward better region-specific management can be expected to improve clinical health outcomes. | Antonio Rollan Juan Pablo Arab M Constanza Camargo Roberto Candia Paul Harris Catterina Ferreccio Charles S Rabkin Juan Cristóbal Gana Pablo Cortés Rolando Herrero Luisa Durán Apolinaria García Claudio Toledo Alberto Espino Nicole Lustig Alberto Sarfatis Catalina Figueroa Javier Torres Arnoldo Riquelme | 2014 | World Journal of Gastroenterology2014，20，31： | 2 |
| 18 | Liver fat deposition and mitochondrial dysfunction in morbid obesity:An approach combining metabolomics with liver imaging and histology显示文摘AIM: To explore the usefulness of magnetic resonance imaging(MRI) and spectroscopy(MRS) for assessment of non-alcoholic fat liver disease(NAFLD) as compared with liver histological and metabolomics findings. METHODS: Patients undergoing bariatric surgery following procedures involved in laparoscopic sleeve gastrectomy were recruited as a model of obesityinduced NAFLD in an observational, prospective, singlesite, cross-sectional study with a pre-set duration of 1 year. Relevant data were obtained prospectively and surrogates for inflammation, oxidative stress and lipid and glucose metabolism were obtained through standard laboratory measurements. To provide reliable data from MRI and MRS, novel procedures were designed to limit sampling variability and other sources of error using a 1.5T Signa HDx scanner and protocols acquired from the 3D or 2D Fat SAT FIESTA prescription manager. We used our previously described 1H NMRbased metabolomics assays. Data were obtained immediately before surgery and after a 12-mo period including histology of the liver and measurement of metabolites. Values from 1H NMR spectra obtained after surgery were omitted due to technical limitations.RESULTS: MRI data showed excellent correlation with the concentration of liver triglycerides, other hepatic lipid components and the histological assessment, w h i c h e xc l u d e d t h e p r e s e n c e o f n o n-a l c o h o l i c steatohepatitis(NASH). MRI was sufficient to follow up NAFLD in obese patients undergoing bariatric surgery and data suggest usefulness in other clinical situations. The information provided by MRS replicated that obtained by MRI using the-CH3 peak(0.9 ppm), the-CH2- peak(1.3 ppm, mostly triglyceride) and the-CH=CH- peak(2.2 ppm). No patient depicted NASH. After surgery all patients significantly decreased their body weight and steatosis was virtually absent even in patients with previous severe disease. Improvement was also observed in the serum concentrations of selected variables. The most relevant findings using metabolomics indicate increased levels of triglyceride and monounsaturated fatty acids in severe steatosis but those results were accompanied by a significant depletion of diglycerides, polyunsaturated fatty acids, glucose-6-phosphate and the ATP/AMP ratio. Combined data indicated the coordinated action on mitochondrial fat oxidation and glucose transport activity and may support the consideration of NAFLD as a likely mitochondrial disease. This concept may helpto explain the dissociation between excess lipid storage in adipose tissue and NAFLD and may direct the search for plasma biomarkers and novel therapeutic strategies. A limitation of our study is that data were obtained in a relatively low number of patients.CONCLUSION: MRI is sufficient to stage NAFLD in obese patients and to assess the improvement after bariatric surgery. Other data were superfluous for this purpose. | Nahum Calvo Raúl Beltrán-Debón Esther Rodríguez-Gallego Anna Hernández-Aguilera Maria Guirro Roger Mariné-Casadó Lidón Millá Josep M Alegret Fàtima Sabench Daniel del Castillo María Vinaixa Miguelàngel Rodríguez Xavier Correig Roberto García-álvarez Javier A Menendez Jordi Camps Jorge Joven | 2015 | World Journal of Gastroenterology2015，21，24： | 2 |
| 19 | Soil moisture pre-treatment effects on enzyme activities as indicators of heavy metal-contaminated and reclaimed soils显示文摘 | M. Belén Hinojosa José A. Carreira Roberto García-Ruíz Richard P. Dick | 2004 | Soil Biology and Biochemistry2004，，10： | 2 |
| 20 | Suitability of enzyme activities for the monitoring of soil quality improvement in organic agricultural systems显示文摘 | Roberto García-Ruiz Victoria Ochoa M. Belén Hinojosa Jose Antonio Carreira | 2008 | Soil Biology and Biochemistry2008，，9： | 2 |
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