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Thermal Hydraulic Analysis Improvement for the IeA-R1 Research Reactor and Fuel Assembly Design Modification

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World Journal of Nuclear Science and Technology 2018年第2期8卷 54-69页

作者： Pedro ernesto Umbehaun Walmir Maximo Torres José antonio Batista Souza Mitsuo Yamaguchi antonio teixeira e silva Roberto Navarro de Mesquita Nikolas Lymberis Scuro Delvonei Alves de Andrade Nuclear and energy Research Institute (Instituto de Pesquisas energéticas e Nucleares) S&auml o Paulo Brazil

This paper presents the sequence of activities to improve the thermal hydraulic analysis of the IeA-R1 research reactor to operate in safe conditions after power upgrade from 2 to 5 MW and core size reduction from 30 to 24 fuel assemblies. A realistic analysis needs the knowledge of the actual operation conditions (heat flow, flow rates) beyond the geometric data and the uncertainties associated with manufacturing and measures. A dummy fuel assembly was designed and constructed to measure the actual flow rate through the core fuel assemblies and its pressure drop. First results showed that the flow distribution over the core is nearly uniform. Nevertheless, the values are below than the calculated ones and the core bypass flow rate is greater than those estimated previously. Based on this, several activities were performed to identify and reduce the bypass flow, such as reduction of the flow rate through the sample irradiators, closing some unnecessary secondary holes on the matrix plate, improvement in the primary flow rate system and better fit of the core components on the matrix plate. A sub-aquatic visual system was used as an important tool to detect some bypass flow path. After these modifications, the fuel assemblies flow rate increased about 13%. Additional tests using the dummy fuel assembly were carried out to measure the internal flow distribution among the rectangular channels. The results showed that the flow rate through the outer channels is 10% - 15% lower than the internal ones. The flow rate in the channel formed between two adjacent fuel assemblies is an estimated parameter and it is difficult to measure because this is an open channel. A new thermal hydraulic analysis of the outermost plates of the fuel assemblies takes into account all this information. Then, a fuel design modification was proposed with the reduction of 50% in the uranium quantity in the outermost fuel plates. In order to avoid the oxidation of the outermost plates by high temperature, low flow rate, a reduction of 50% in th

关键词： Nuclear Research Reactor Uranium Reduction Thermal Hydraulic Analysis Flow Measurement Dummy Fuel Assembly

Renin-angiotensin system in the central nervous system:focus on Huntington’s disease

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Neural Regeneration Research 2023年第10期18卷 2206-2207页

作者： Aline silva de Miranda antonio Lucio teixeira Laboratório de Neurobiologia Departamento de MorfologiaInstituto de Ciências BiológicasUniversidade Federal de Minas Gerais(UFMG)Belo HorizonteMGBrasil Laboratório Interdisciplinar de Investigação Médica(LIIM) Faculdade de MedicinaUniversidade Federal de Minas Gerais(UFMG)Belo HorizonteMGBrasil Neuropsychiatry Program Department of Psychiatry and Behavioral SciencesMcGovern Medical SchoolUniversity of Texas Health Science Center at HoustonTXUSA Faculdade Santa Casa BH Belo HorizonteMGBrasil

The renin-angiotensin system(RAS)was originally conceived as a circulating hormonal system involved in the regulation of cardiovascular and renal homeostasis.With the discovery of local RAS components in diverse organ... 详细信息

关键词： Huntington organs angiotensin

Development of a Ready-to-Use PSMA-11 Kit Formulation and Biological evaluation of Binding Affinity

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Advances in Molecular Imaging 2024年第2期13卷 7-22页

作者： Maria Renata Valente Brandão Freire Natália Marchesan Bexiga Marco antonio Stephano João ezequiel Oliveira Carlos Roberto Jorge Soares Ana Cláudia Camargo Miranda Anna Carolina de Alcântara Barbosa Marycel Figols de Barboza Laura Fernanda Garcia Luiz Felipe S. teixeira Maria Helena Marumo Bellini Natanael Gomes da silva Luiza Mascarenhas Balieiro Joel Mendes elaine Bortoleti de Araújo Centro de Radiofarmcia Instituto de Pesquisas Energticas e Nucleares (IPEN) Cidade Universitria So Paulo Brasil Departamento de Tecnologia Farmacutica Faculdade de Cincias Farmacuticas (USP) Cidade Universitria So Paulo Brasil Centro de Biotecnologia Instituto de Pesquisas Energticas e Nucleares (IPEN) Cidade Universitria So Paulo Brasil Departamento de Medicina Nuclear do Hospital Israelita Albert einstein So Paulo/SP Brasil

Introduction: 68Ga-PSMA-11 is considered the gold standard in detection of micro and oligometastases in advanced prostate cancer, being used for therapeutic planning, as well as, potentially, for evaluating response to treatment. The development of ready-to-use lyophilized kit of PSMA-11 adds quality and safety to the routine use of this radiopharmaceutical and represents a pharmacotechnical challenge as it must preserve the integrity and specificity of the ligand. Methods: PSMA-11 kit formulation was proposed, considering radiolabeling parameters and the preservation of the peptide during the lyophilization process, using mannitol as an excipient. Critical temperature characterization studies were carried out using DSC equipment and the freeze-drying process was developed. The direct radiolabeling conditions were evaluated and standardized using 68Ge/68Ga generator eluate from two different manufacturers (ITG and eckert & Ziegler). The radiochemical purity was evaluated by TLC and HPLC. Biological evaluation was carried out with lyophilized PSMA-11 to demonstrate the integrity of the peptide and preservation of biological activity after the lyophilization process. Results: Based on critical temperature characterization studies, the freeze-drying cycle was designed to reach a freezing temperature of around −40˚C and primary drying at 2˚C. Using 20 mg of mannitol, an intact and elegant lyophilized cake was obtained. PSMA-11 lyophilized kit was directly labeled with 68Ga eluate from 68Ge/68Ga GMP generators (ITG and eckert & Ziegler) resulting in % RP > 95% at pH 4.0 to 4.5. The results obtained from in vitro and in vivo biological competition studies confirmed the preservation of PSMA-11 affinity for the receptor after lyophilization. Conclusion: A lyophilized formulation (Kit) of PSMA-11 was successfully obtained, which preserved the integrity and biological activity of the peptide and guaranteed radiolabeling efficiency.

关键词： 68Ga-PSMA-11 Prostate-Specific Membrane Antigen (PSMA) Ready-to-Use Kit GMP-Grade Generators Metastatic Prostate Cancer PeT Imaging

Assessment of retracted papers,and their retraction notices,from a cancer journal associated with“paper mills”

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数据与情报科学学报:英文版 2023年第2期8卷 118-125页

作者： Jaime A.teixeira da silva Serhii Nazarovets Independent researcher Ikenobe 3011-2Kagawa-ken761-0799Japan Borys Grinchenko Kyiv University 18/2 Bulvarno-Kudriavska Str.04053 KyivUkraine

Cancer research is occasionally described as being in a reproducibility crisis.The cancer literature has ample papers retracted due to misconduct,including the use of paper mills,invalid authorship,or fake data.The objective of this paper was to gain an appreciation of the balance of retractions and associated retraction notices of 23 retracted Cancer Biotherapy and Radiopharmaceuticals papers associated with paper mills.By 23 March 2023,these retracted papers had already accumulated 287 citations according to Web of Science Core Collection,253 according to Scopus,and 365 according to Google Scholar,i.e.,metrically speaking,they were highly rewarded.All authors had an affiliation(71%being a hospital)in China.Most(12/21;57%)of corresponding authors had emails with a@*** suffix.Four of the retraction notices(i.e.,17%)explicitly indicated paper mills as a reason for retraction although,in general,the retraction notices lacked details and background that could assist readers’understanding of the retractions.

关键词： Indexing Oncology Publishing history PubMed Retraction Notices Transparency

Structural and optical properties of pillared eu^(3+)-containing layered double hydroxides intercalated by 2-to 12-carbon aliphatic dicarboxylates

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Journal of Rare earths 2022年第2期40卷 260-267,I0003页

作者： Alexandre Candido teixeira Ivan Guide Nunes silva Alysson Ferreira Morais Danilo Mustafa Physics Institute.University of Sao Paulo 05508-090Sao PauloSPBrazil

While the versatile composition of layered double hydroxides(LDHs)allows the introduction of almost any polyvalent cation in their structure,the exchangeable negatively charged ions intercalated between the plates increase their vast range of functionalities.Here we report on the preparation and optical properties of pillared eu^(3+)-substituted ZnAl LDHs intercalated by aliphatic dicarboxylates:-OOC-(CH_(2))_(n-2)-COO-.The basal distance in these materials is dependent on the size and packing of the intercalated anions.By varying the number(n)of carbon atoms in the aliphatic chain from 2 to 12,the interlayer gallery of these ZnAleu LDHs is considerably expanded from 0.9 to 2.1 nm.In the interlayer gallery,the aliphatic dicarboxylates form a monolayer,with the aliphatic chain inclined by an angleα≈63°with the hydroxide layers.The carbon atom in the COO-group is 0.43 nm far from the metal plane,showing that these carboxylates are not grafted in the brucite-like layers.These LDHs are thermally stable up to around 150℃,after which dehydroxylation of the hydroxide layers is observed.The Judd-Ofelt intensity parameters were obtained and compared to the eu^(3+)-containing complexes with the same ligand series indicating a more symmetrical and less polarizable chemical environment around the rare earth ion.

关键词： europium Layered double hydroxides Carboxylate ligands Luminescence Rare earths

Antioxidants enzymes Activities and NO Levels in Hemodialysis and Continuous Ambulatory Peritoneal Dialysis—A Comparative Study

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Journal of Biosciences and Medicines 2024年第2期12卷 50-59页

作者： Natalia Cristina Aparecida Ribeiro e Ribeiro Anderson Martins Tavares Jaslana Hainfellner da silva João Paulo Lima Daher Salim Kanaan Luciene de Carvalho Cardoso-Weide Laboratory of Neuroplasticity Neurobiology Department Biology Institute Federal Fluminense University Rio de Janeiro Brazil Postgraduate Program in Medical Sciences School of Medicine Federal Fluminense University Rio de Janeiro Brazil School of Biology UNIVERSO—Salgado de Oliveira University Rio de Janeiro Brazil Department of Pathology Faculty of Medicine Federal Fluminense University Rio de Janeiro Brazil

It consists of a retrospective study with twenty-two individuals diagnosed with DRC: fourteen HD and eight CAPD, followed up in the dialysis center of antonio Pedro University Hospital (HUAP) of Fluminense Federal University (UFF), between 2015 and 2017. Fifteen healthy control (HC) subjects were included, without diagnosed CKD. Patients with HIV positive, hepatitis A, B, and C, pregnant, cancer, smokers, alcoholics and those exposed to X-rays in the last 3 months, were excluded. Objectives: As oxidative stress and endothelial dysfunction may be linked to the higher prevalence of CVD in CKD patients, we measured the activities of the antioxidants enzymes: SOD and GPx and total NO levels in the plasma and serum of end-stage CKD patients undergoing dialysis therapy, comparing with the HC group. Methods: Quantification of NO levels was performed by fluorometric kit, while activities of SOD and GPx were determined using kinetic methods. Results: We found higher plasma SOD activity in HD (8.58 U/ml) and CAPD (10.14 U/ml), compared to C (3.73 U/ml) group, while GPx activity was decreased in HD (115.38 nmol/h/ml) and CAPD (122.76 nmol/h/ml) groups compared to HC group (275.83 nmol/h/ml). Total serum NO concentration was decreased in HD (14.09 pmol/μl) and CAPD (10.26 pmol/μl), compared to non-CKD patients (49.65 pmol/μl). Conclusion: Decreased total serum NO and GPx activities may lead to endothelial dysfunction and consequently a higher prevalence of CVD in CKD patients.

关键词： Hemodialysis CAPD SOD GPx NO

How does the brown mussel Perna perna respond to environmental pollution?A review on pollution biomarkers

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Journal of environmental Sciences 2022年第1期34卷 412-428页

作者： Fernanda silva dos Santos Raquel A.F.Neves Mirian Araújo Carlos Crapez Valéria Laneuville teixeira Natascha Krepsky Fluminense Federal University(UFF) Institute of BiologyGraduate Program in Science and BiotechnologyMario Santos Braga Streets/n.CentroNiteróiRJ CEP 24.020-141Brazil Federal University of the State of Rio de Janeiro(UNIRIO) Institute of Biosciences(IBIO)Graduate Program in Neotropical Biodiversity(PPGBIO)Pasteur Avenue458.UrcaRio de JaneiroRJ CEP 22.290-255Brazil Fluminense Federal University(UFF) Institute of BiologyGraduate Program in Marine Biology and Coastal EnvironmentsMario Santos Braga Streets/n.CentroNiteróiRJ CEP 24.020-141Brazil Federal University of the State of Rio de Janeiro(UNIRIO) Institute of Biosciences(IBIO)Graduate Program in Ecotourism and ConservationPasteur Avenue458.UrcaRio de JaneiroRJ CEP 22.290-255Brazil

The brown mussel Perna perna(Linnaeus,1758)is a valuable resource for aquaculture in tropical and subtropical coastal regions.It presents desirable characteristics for biomonitoring,including being sessile,widely distributed and abundant,and is a filter-feeder able to accumulate several classes of pollutants(e.g.,metals,hydrocarbons,among others).Mussels’biological responses to pollution exposure can be measured as biomarkers,which include alterations ranging from molecular to physiological levels,to estimate the degree of environmental contamination and its effects on biota.This full review compiles two decades(2000–2020)of literature concerning biological effects on P.perna mussel caused by environmental pollutants(i.e.,metals,hydrocarbons,and emerging pollutants),considering environmental and farm-based biomonitoring.Biochemical markers related to mussels’oxidative status were efficient for the biomonitoring of metals(i.e.,antioxidant enzymes associated with oxidative damage in biomolecules).Genotoxicity and cytotoxicity indicators(i.e.,comet,micronucleus,and neutral red assays)provided a depiction of hydrocarbon contamination.The neutral red assay gave a time-concentration cytotoxic response to a wide range of pollutants,including emerging pollutants(e.g.,pharmaceuticals and biocides)and hydrocarbons.Perna perna hemocyte parameters provided a useful approach for biocide biomonitoring.This paper summarizes useful biomarkers from molecular to physiological levels in this mussel species used to identify and quantify the degree of coastal pollution.An integrated biomarker analysis may provide a way to overcome possible biomarker variations and assess multi-polluted sites.Nevertheless,it is necessary to investigate biomarker variations according to natural factors(e.g.,season and gonad maturation stage)to standardize them for trustworthy biomonitoring.

关键词： Biological indexes Biomonitoring emerging pollutants Hydrocarbons Metals Sentinel species

Renin angiotensin system in liver diseases: Friend or foe?

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World Journal of Gastroenterology 2017年第19期23卷 3396-3406页

作者： Ana Cristina Simoes e silva Aline S Miranda Natália P Rocha antonio L teixeira Department of Pediatrics Faculty of MedicineFederal University of Minas Gerais Interdisciplinary Laboratory of Medical Investigation Faculty of MedicineUFMG Laboratory of Neurobiology Department of MorphologyInstitute of Biological SciencesUFMG Neuropsychiatry Program Department of Psychiatry and Behavioral SciencesMcGovern Medical SchoolUniversity of Texas Health Science Center at Houston

In the last three decades,the understanding of the renin angiotensin system(RAS)has been changed by the discoveries of functional local systems,novel biologically active peptides,additional specific receptors,alternative pathways of angiotensin(Ang)?Ⅱ?generation,and new roles for enzymes and precursor components other than those in Ang?Ⅱ?synthesis.In this regard,the discovery that Ang-(1-7)opposes the pressor,proliferative,pro-fibrotic,and pro-inflammatory effects mediated by Ang?Ⅱ?has contributed to the realization that the RAS is composed of two axes.The first axis consists of the angiotensin-converting enzyme(ACe),with Ang?Ⅱ?as the end product,and the angiotensin type 1(AT1)receptor as the main effector mediating the biological actions of Ang?Ⅱ.The second axis results from ACe2-mediated hydrolysis of Ang?Ⅱ,leading to the production of Ang-(1-7),with the Mas receptor as the main effector conveying the vasodilatory,antiproliferative,anti-fibrotic,and anti-inflammatory effects of Ang-(1-7).experimental and clinical studies have shown that both axes of the RAS may take part in the pathogenesis of liver diseases.In this manuscript,we summarize the current evidence regarding the role of RAS in hepatic cirrhosis and its complications,including hemodynamic changes and hepatorenal syndrome.The therapeutic potential of the modulation of RAS molecules in liver diseases is also discussed.

关键词： Renin angiotensin system Angiotensin Ⅱ Angiotensin-(1-7) Hepatic cirrhosis Liver fibrosis Hepatorenal syndrome

Delay Times and Clinical Outcomes in Acute Myocardial Infarction: Comparison of Periods before and during the COVID-19 Pandemic—Myocardial Infarction and the Pandemic

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World Journal of Cardiovascular Diseases 2024年第6期14卷 392-400页

作者： Clarice teixeira silva Araújo Arnon Salviato Mameri Thúlio Carrera Guarçoni Venturini Marcus Tadeu Aguilar Constantino Matos Igor Morais Araujo Lopes Luiz Gustavo Ribeiro de Carvalho Murad Cleberson Duartes Ovani Guilherme Vassalo Morais Fernanda Venturini de Castro Danielle Lopes Rocha Lucas Crespo de Barros Rodolfo Costa Sylvestre Luiz Fernando Machado Barbosa Roberto Ramos Barbosa Internal Medicine Universidade Federal do Esprito Santo (UFES) Vitria Brazil Hospital Santa Casa de Misericrdia de Vitria Vitria Brazil Hospital Santa Rita de Cssia Vitria Brazil Hospital estadual Dr. Jayme Santos Neves Serra Brazil Grupo Kora Sade Vitria Brazil Hospital estadual Infantil e Maternidade Alzir Bernardino Alves (HIMABA) Vila Velha Brazil

Introduction: At the beginning of the COVID-19 pandemic, a drop in the number of patients treated for cardiac emergencies raised concern about cardiovascular mortality in that period. An increase in care delay for patients with ST-segment elevation myocardial infarction (STeMI) may have affected clinical outcomes. Objectives: To analyze delay times and clinical outcomes of patients with STeMI undergoing primary percutaneous coronary intervention (PPCI), before and during the COVID-19 pandemic. Methods: Retrospective observational study that included patients with STeMI undergoing PPCI from December 2018 to July 2021. The COVID-19 pandemic cases were divided into two groups: pandemic I—from March to August 2020;and pandemic II—from September 2020 to July 2021. Patients were compared according to the period of hospitalization. Primary outcomes were delay times in assistance and clinical outcomes (acute kidney injury [AKI], post-procedural vascular complications and in-hospital mortality). Results: 108 patients were included, 39 (36.1%) in the pre-pandemic period, 13 (12.1%) in pandemic I and 56 (51.8%) in pandemic II. Time from onset of symptoms to arrival at the service and door-to-balloon time did not differ significantly among groups. Vascular complications were more frequent during the pandemic (I and II) than in the pre-pandemic period (2.5% pre-pandemic vs 15.4% pandemic vs 12.5% pandemic II;p = 0.03). AKI incidence was similar in all three periods. There was a non-significant increase in in-hospital mortality during the COVID-19 pandemic. Conclusion: In patients with STeMI, there was an increase in vascular complications and a trend toward increased mortality during the COVID-19 pandemic. Delay times to admission and reperfusion did not differ significantly between before and during the pandemic.

关键词： Myocardial Infarction Primary Percutaneous Coronary Intervention Coronary Reperfusion Pandemic COVID-19