21 results on '"Guimarães RR"'
Search Results
2. Novel Gadolinium-Free Ultrasmall Nanostructured Positive Contrast for Magnetic Resonance Angiography and Imaging.
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Kawassaki RK, Romano M, Klimuk Uchiyama M, Cardoso RM, Baptista MS, Farsky SHP, Chaim KT, Guimarães RR, and Araki K
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- Rats, Animals, Gadolinium, Rats, Wistar, Magnetic Resonance Imaging methods, Chelating Agents, Contrast Media, Magnetic Resonance Angiography
- Abstract
Nanostructured contrast agents are promising alternatives to Gd
3+ -based chelates in magnetic resonance (MR) imaging techniques. A novel ultrasmall paramagnetic nanoparticle (UPN) was strategically designed to maximize the number of exposed paramagnetic sites and r1 while minimizing r2 , by decorating 3 nm titanium dioxide nanoparticles with suitable amounts of iron oxide. Its relaxometric parameters are comparable to those of gadoteric acid (GA) in agar phantoms, and the r2 / r1 ratio of 1.38 at 3 T is close to the ideal unitary value. The strong and prolonged contrast enhancement of UPN before renal excretion was confirmed by T1 -weighted MR images of Wistar rats after intravenous bolus injection. Those results associated with good biocompatibility indicate its high potential as an alternative blood-pool contrast agent to the GA gold standard for MR angiography, especially for patients with severe renal impairment.- Published
- 2023
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3. Urinary tubular biomarkers as predictors of death in critically ill patients with COVID-19.
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Bezerra GF, Meneses GC, Albuquerque PL, Lopes NC, Santos RS, da Silva JC, Mota SM, Guimarães RR, Guimarães FR, Guimarães ÁR, Adamian CM, de Lima PR, Bandeira IC, Dantas MM, Junior GB, Oriá RB, Daher EF, and Martins AM
- Subjects
- Biomarkers, Critical Illness, Hepatitis A Virus Cellular Receptor 1, Humans, Lipocalin-2, Prospective Studies, Acute Kidney Injury diagnosis, COVID-19
- Abstract
Aim: To evaluate the prediction capacity of urinary biomarkers for death in critically ill patients with COVID-19. Methods: This is a prospective study with critically ill patients due to COVID-19 infection. The urinary biomarkers NGAL, KIM-1, MCP-1 and nephrin were quantified on ICU admission. Results: There was 40% of death. Urinary nephrin and MCP-1 had no association with death. Tubular biomarkers (proteinuria, NGAL and KIM-1) were predictors of death and cut-off values of them for death were useful in stratify patients with worse prognosis. In a multivariate cox regression analysis, only NGAL remains associated with a two-mount survival chance. Conclusion: Kidney tubular biomarkers, mostly urinary NGAL, had useful capacity to predict death in critically ill COVID-19 patients.
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- 2022
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4. Impact of Three Methods of Ischemic Preconditioning on Ischemia-Reperfusion Injury in a Pig Model of Liver Transplantation.
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Belon AR, Tannuri ACA, de Albuquerque Rangel Moreira D, Figueiredo JL, da Silva AM, Serafini S, Guimarães RR, Faria CS, de Alexandre AS, Gonçalves JO, Paes VR, and Tannuri U
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- Animals, Aspartate Aminotransferases, Liver pathology, Swine, Ischemic Preconditioning methods, Liver Transplantation adverse effects, Reperfusion Injury etiology, Reperfusion Injury metabolism, Reperfusion Injury prevention & control
- Abstract
Background: Ischemic preconditioning (IPC), either direct (DIPC) or remote (RIPC), is a procedure aimed at reducing the harmful effects of ischemia-reperfusion (I/R) injury., Objectives: To assess the local and systemic effects of DIPC, RIPC, and both combined, in the pig liver transplant model., Materials and Methods: Twenty-four pigs underwent orthotopic liver transplantation and were divided into 4 groups: control, direct donor preconditioning, indirect preconditioning at the recipient, and direct donor with indirect recipient preconditioning. The recorded parameters were: donor and recipient weight, graft-to-recipient weight ratio (GRWR), surgery time, warm and cold ischemia time, and intraoperative hemodynamic values. Blood samples were collected before native liver removal (BL) and at 0 h, 1 h, 3 h, 6 h, 12 h, 18 h, and 24 h post-reperfusion for the biochemical tests: aspartate aminotransferase (AST), alanine aminotransferase (ALT), alkaline phosphatase (ALP), gamma-glutamyl transferase (GGT), creatinine, BUN (blood urea nitrogen), lactate, total and direct bilirubin. Histopathological examination of liver, gut, kidney, and lung fragments were performed, as well as molecular analyses for expression of the apoptosis-related BAX (pro-apoptotic) and Bcl-XL (anti-apoptotic) genes, eNOS (endothelial nitric oxide synthase) gene, and IL-6 gene related to inflammatory ischemia-reperfusion injury, using real-time polymerase chain reaction (RT-PCR)., Results: There were no differences between the groups regarding biochemical and histopathological parameters. We found a reduced ratio between the expression of the BAX gene and Bcl-XL in the livers of animals with IPC versus the control group., Conclusions: DIPC, RIPC or a combination of both, produce beneficial effects at the molecular level without biochemical or histological changes.
- Published
- 2022
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5. Outcome of SARS-CoV-2 Infection in 121 Patients with Inborn Errors of Immunity: A Cross-Sectional Study.
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Goudouris ES, Pinto-Mariz F, Mendonça LO, Aranda CS, Guimarães RR, Kokron C, Barros MT, Anísio F, Alonso MLO, Marcelino F, Valle SOR, Junior SD, Barreto IDP, Ferreira JFS, Roxo-Junior P, do Rego Silva AM, Campinhos FL, Bonfim C, Loth G, Fernandes JF, Garcia JL, Capelo A, Takano OA, Nadaf MIV, Toledo EC, Cunha LAO, Di Gesu RSW, Schidlowski L, Fillipo P, Bichuetti-Silva DC, Soldateli G, Ferraroni NR, de Oliveira Dantas E, Pestana S, Mansour E, Ulaf RG, Prando C, Condino-Neto A, and Grumach AS
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- Adult, Asymptomatic Diseases, Brazil, COVID-19 mortality, Cross-Sectional Studies, Disease Progression, Female, Humans, Male, Middle Aged, Primary Immunodeficiency Diseases mortality, Severity of Illness Index, Survival Analysis, Systemic Inflammatory Response Syndrome mortality, Young Adult, COVID-19 diagnosis, Primary Immunodeficiency Diseases diagnosis, SARS-CoV-2 physiology, Systemic Inflammatory Response Syndrome diagnosis
- Abstract
Purpose: There is still scarce data on SARS-CoV-2 infection in patients with Inborn Errors of Immunity (IEI) and many unresolved questions. We aimed to describe the clinical outcome of SARS-CoV-2 infection in Brazilian IEI patients and identify factors influencing the infection., Methods: We did a cross-sectional, multicenter study that included patients of any age affected by IEI and SARS-CoV-2 infection. The variables studied were sex, age, type of IEI, comorbidities (number and type), treatment in use for IEI, clinical manifestations and severity of SARS-CoV-2 infection., Results: 121 patients were included: 55.4% female, ages from six months to 74 yo (median age = 25.1 yo). Most patients had predominantly antibody deficiency (n = 53). The infection was mostly asymptomatic (n = 21) and mild (n = 66), and one child had multisystem inflammatory syndrome (MIS-C). We could not observe sex-related susceptibility, and there was a weak correlation between age and severity of infection. The number of comorbidities was higher in severe cases, particularly bronchiectasis and cardiopathy. There were no severe cases in hereditary angioedema patients. Six patients aged 2 to 74 years died, three of them with antibody deficiency., Conclusion: The outcome was mild in most patients, but the Case Fatality Ratio was higher than in the general population. However, the type of IEI was not a determining factor for severity, except for complement deficiencies linked to milder COVID-19. The severity of SARS-CoV-2 infection seems to be more related to older age, a higher number of comorbidities and type of comorbidities (bronchiectasis and cardiopathy)., (© 2021. The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature.)
- Published
- 2021
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6. Development of muffins as dialysis snacks for patients undergoing hemodialysis: results of chemical composition and sensory analysis.
- Author
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Machado J, Miyahira RF, Marques M, Moura-Nunes N, Guimarães RR, Zago L, Santana I, Leite Junior M, and Avesani CM
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- Adult, Cross-Sectional Studies, Female, Food Preferences, Humans, Male, Taste, Renal Dialysis adverse effects, Snacks
- Abstract
Objective: This study aimed to develop two non-industrial food products as financially accessible options to prevent and treat malnutrition in hemodialysis (HD) patients. These food products were developed and intended for use as dialysis snacks., Methods: This is a cross-sectional and multi-step study. First, 183 adult HD patients (55 ± 14 years; 50.8% males), replied to a questionnaire with their food preferences regarding taste (salty, sweet, bitter, sour) and consistency (liquid, solid, pasty) for a dialysis snack. Most patients preferred a food product with a solid consistency (90%) and a salty flavor (81.4%). Second, three muffin formulations of fine herbs were developed; one enriched with whey protein concentrate (WPC), a second with textured soy protein (TSP) and a third standard formulation without protein for comparison with the protein-enriched muffins, for which the chemical and nutritional compositions were analyzed. In the third step, 60 patients on HD (61 ± 15 years; 53% males) were enrolled in a sensory analysis by applying a 9-point structured hedonic scale, ranging from "extremely liked" (score 9) to "extremely disliked" (score 1)., Results: When compared with the standard formulation, the formulations enriched with WPC and TSP protein had a significantly higher amount of protein/serving (Standard: 5.9 ± 0.3 g vs WPC: 14.5 ± 0.9 g and TSP 10.8 ± 0.7 g; P < 0.05) but a lower amount of carbohydrate (Standard: 13.1 ± 2.2 g vs WPC: 5.6 ± 0.8 g and TSP 6.0 ± 1.2 g vs; P < 0.05). The mineral content/serving of the protein-enriched muffins was low in phosphorus (50 mg) and sodium (180 mg). The potassium content/serving was moderate for the WPC muffin (225.2 mg) and low for the TSP muffin (107.9 mg). The acceptability index (AI) for the enriched protein muffins was higher than 70% and similar to the standard formulation., Conclusion: The muffins with fine herbs and enriched with protein were well-accepted by all patients and appropriate to serve as dialysis snacks for HD patients., (© 2020. The Author(s).)
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- 2021
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7. Combined immunodeficiencies.
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Aranda CS, Guimarães RR, and de Gouveia-Pereira Pimentel M
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- Humans, Infant, Newborn, Neonatal Screening, T-Lymphocytes, Immunologic Deficiency Syndromes diagnosis, Severe Combined Immunodeficiency
- Abstract
Objectives: Inborn Errors of Immunity (IEI), also known as primary immunodeficiencies, correspond to a heterogeneous group of congenital diseases that primarily affect immune response components. The main clinical manifestations comprise increased susceptibility to infections, autoimmunity, inflammation, allergies and malignancies. The aim of this article is to review the literature on combined immunodeficiencies (CIDs) focusing on the diagnosis and treatment and the particularities of the clinical management of these patients., Source of Data: Critical integrative review, aimed to present articles related to primary immunodeficiencies combined with a searchin the PubMed and SciELO databases, with evaluation of publications from the last twenty years that were essential for the construction of knowledge on this group of diseases., Summary of Data: We highlight the main characteristics of CIDs, dividing them according to their pathophysiological mechanisms, such as defects in the development of T cells, TCR signaling, co-stimulatory pathways, cytokine signaling, adhesion, migration and organization of the cytoskeleton, apoptosis pathways, DNA replication and repair and metabolic pathways. In CIDs, clinical manifestations vary widely, from sinopulmonary bacterial infections and diarrhea to opportunistic infections, caused by mycobacteria and fungi. Neonatal screening makes it possible to suspect these diseases before clinical manifestations appear., Conclusions: The CIDs or IEI constitute a complex group of genetic diseases with T-cell involvement. Neonatal screening for these diseases has improved the prognosis of these patients, especially in severe ones, known as SCIDs., (Copyright © 2020 Sociedade Brasileira de Pediatria. Published by Elsevier Editora Ltda. All rights reserved.)
- Published
- 2021
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8. Implementation of a rapid response team in a large nonprofit Brazilian hospital: improving the quality of emergency care through Plan-Do-Study-Act.
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Almeida MC, Portela MC, Paiva EP, Guimarães RR, Pereira Neto WC, Cardoso PR, Mattos DA, Mendes IMACC, Tavares MV, Jácome GPO, and Fernandes GC
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- Brazil, Humans, Emergency Medical Services standards, Hospital Rapid Response Team organization & administration, Hospitals, Quality Improvement
- Abstract
Objective: To describe the implementation of a rapid response team in a large nonprofit hospital, indicating relevant issues for other initiatives in similar contexts, particularly in Latin America., Methods: In general terms, the intervention consisted of three major components: (1) a tool to detect aggravation of clinical conditions in general wards; (2) the structuring of a rapid response team to attend to all patients at risk; and (3) the monitoring of indicators regarding the intervention. This work employed four half-year Plan-Do-Study-Act cycles to test and adjust the intervention from January 2013 to December 2014., Results: Between 2013 and 2014, the rapid response team attended to 2,296 patients. This study showed a nonsignificant reduction in mortality from 8.3% in cycle 1 to 5.0% in cycle 4; however, death rates remained stable in cycles 3 and 4, with frequencies of 5.2% and 5.0%, respectively. Regarding patient flow and continuum of critical care, which is a premise of the rapid response system, there was a reduction in waiting time for intensive care unit beds with a decrease from 45.9% to 19.0% in the frequency of inpatients who could not be admitted immediately after indication (p < 0.001), representing improved patient flow in the hospital. In addition, an increase in the recognition of palliative care patients from 2.8% to 10.3% was noted (p = 0.005)., Conclusion: Implementing a rapid response team in contexts where there are structural restrictions, such as lack of intensive care unit beds, may be very beneficial, but a strategy of adjustment is needed.
- Published
- 2019
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9. Transient Superdiffusion and Long-Range Correlations in the Motility Patterns of Trypanosomatid Flagellate Protozoa.
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Alves LG, Scariot DB, Guimarães RR, Nakamura CV, Mendes RS, and Ribeiro HV
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- Leishmania physiology, Leishmania braziliensis physiology, Models, Biological, Movement physiology, Trypanosoma brucei brucei physiology, Trypanosoma cruzi physiology, Trypanosomatina physiology
- Abstract
We report on a diffusive analysis of the motion of flagellate protozoa species. These parasites are the etiological agents of neglected tropical diseases: leishmaniasis caused by Leishmania amazonensis and Leishmania braziliensis, African sleeping sickness caused by Trypanosoma brucei, and Chagas disease caused by Trypanosoma cruzi. By tracking the positions of these parasites and evaluating the variance related to the radial positions, we find that their motions are characterized by a short-time transient superdiffusive behavior. Also, the probability distributions of the radial positions are self-similar and can be approximated by a stretched Gaussian distribution. We further investigate the probability distributions of the radial velocities of individual trajectories. Among several candidates, we find that the generalized gamma distribution shows a good agreement with these distributions. The velocity time series have long-range correlations, displaying a strong persistent behavior (Hurst exponents close to one). The prevalence of "universal" patterns across all analyzed species indicates that similar mechanisms may be ruling the motion of these parasites, despite their differences in morphological traits. In addition, further analysis of these patterns could become a useful tool for investigating the activity of new candidate drugs against these and others neglected tropical diseases.
- Published
- 2016
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10. Description of Dichelacera (Dichelacera) walteri n. sp. (Diptera: Tabanidae) with a Key to Related Species in the Subgenus Dichelacera Macquart.
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Guimarães RR, Gorayeb IS, Rodrigues-Guimarães R, Seppa GS, and Carvalho RW
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- Animals, Brazil, Diptera anatomy & histology, Female, Diptera classification
- Abstract
Dichelacera (Dichelacera) walteri Guimarães, Gorayeb & Rodrigues-Guimarães n. sp. is described from female specimens collected in Marambaia Island, located in Mangaratiba County, state of Rio de Janeiro, Brazil. The characterization of the species was based in the following characters: a medium-sized species, more sclerotized than others in the subgenus Dichelacera Macquart, the second segment of palp with dark setae and longer than the third antennal segment, a brown scutum with pruinescence on the anterior half and posterior edges with white tonality, yellow dorsum of abdomen with the last three segments brown, white-yellowish venter with yellow setae, narrow frons with dark brown callus, extending just beyond a ridge in the middle of the frons, vertex with ocelli, hyaline wings with three large black bands, and tricolored legs.
- Published
- 2015
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11. Effects of ischemic preconditioning in a pig model of large-for-size liver transplantation.
- Author
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Leal AJ, Tannuri AC, Belon AR, Guimarães RR, Coelho MC, Gonçalves Jde O, Serafini S, Melo ES, and Tannuri U
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- Acidosis complications, Alanine Transaminase metabolism, Animals, Apoptosis physiology, Aspartate Aminotransferases metabolism, Biomarkers metabolism, Gene Expression, Hydrogen-Ion Concentration, Liver anatomy & histology, Liver Transplantation adverse effects, Models, Animal, Nitric Oxide Synthase metabolism, Organ Size, Potassium blood, Random Allocation, Reperfusion Injury metabolism, Reverse Transcriptase Polymerase Chain Reaction, Sodium blood, Swine, Transforming Growth Factor beta metabolism, Tumor Necrosis Factor-alpha metabolism, bcl-2-Associated X Protein metabolism, Hepatocytes metabolism, Ischemic Preconditioning methods, Liver blood supply, Liver Transplantation methods, Reperfusion Injury prevention & control
- Abstract
Objective: In most cases of pediatric liver transplantation, the clinical scenario of large-for-size transplants can lead to hepatic dysfunction and a decreased blood supply to the liver graft. The objective of the present experimental investigation was to evaluate the effects of ischemic preconditioning on this clinical entity., Methods: Eighteen pigs were divided into three groups and underwent liver transplantation: a control group, in which the weights of the donors were similar to those of the recipients, a large-for-size group, and a large-for-size + ischemic preconditioning group. Blood samples were collected from the recipients to evaluate the pH and the sodium, potassium, aspartate aminotransferase and alanine aminotransferase levels. In addition, hepatic tissue was sampled from the recipients for histological evaluation, immunohistochemical analyses to detect hepatocyte apoptosis and proliferation and molecular analyses to evaluate the gene expression of Bax (pro-apoptotic), Bcl-XL (anti-apoptotic), c-Fos and c-Jun (immediate-early genes), ischemia-reperfusion-related inflammatory cytokines (IL-1, TNF-alpha and IL-6, which is also a stimulator of hepatocyte regeneration), intracellular adhesion molecule, endothelial nitric oxide synthase (a mediator of the protective effect of ischemic preconditioning) and TGF-beta (a pro-fibrogenic cytokine)., Results: All animals developed acidosis. At 1 hour and 3 hours after reperfusion, the animals in the large-for-size and large-for-size + ischemic preconditioning groups had decreased serum levels of Na and increased serum levels of K and aspartate aminotransferase compared with the control group. The molecular analysis revealed higher expression of the Bax, TNF-alpha, I-CAM and TGF-beta genes in the large-for-size group compared with the control and large-for-size + ischemic preconditioning groups. Ischemic preconditioning was responsible for an increase in c-Fos, IL-1, IL-6 and e-NOS gene expression., Conclusion: Ischemia-reperfusion injury in this model of large-for-size liver transplantation could be partially attenuated by ischemic preconditioning.
- Published
- 2015
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12. [Macrophage activation syndrome in a patient with systemic juvenile idiopathic arthritis].
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Tavares AC, Ferreira GA, Guimarães LJ, Guimarães RR, and Santos FP
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- Child, Female, Humans, Arthritis, Juvenile complications, Macrophage Activation Syndrome etiology
- Abstract
Machrophage activation syndrome (MAS) is a rare and potentially fatal disease, commonly associated with chronic rheumatic diseases, mainly juvenile idiopathic arthritis. It is included in the group of secondary forms of haemophagocytic syndrome, and other causes are lymphoproliferative diseases and infections. Its most important clinical and laboratorial manifestations are non-remitting fever, splenomegaly, bleeding, impairment of liver function, cytopenias, hypoalbuminemia, hypertriglyceridemia, hypofibrinogenemia and hyperferritinemia. The treatment needs to be started quickly, and the majority of cases have a good response with corticosteroids and cyclosporine. The Epstein-Barr virus is described as a possible trigger for many cases of MAS, especially in these patients in treatment with tumor necrosis factor (TNF) blockers. In these refractory cases, etoposide (VP16) should be administered, associated with corticosteroids and cyclosporine. Our objective is to describe a rare case of MAS probably due to EBV infection in a subject with systemic-onset juvenile idiopathic arthritis, which achieved complete remission of the disease after therapy guided by 2004-HLH protocol., (Copyright © 2014 Elsevier Editora Ltda. All rights reserved.)
- Published
- 2015
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13. Large-for-size liver transplantation: a flowmetry study in pigs.
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Rangel Moreira Dde A, Aoun Tannuri AC, Belon AR, Mendonça Coelho MC, Oliveira Gonçalves J, Serafini S, Roberto Lima F, Agostini LO, Guimarães RR, and Tannuri U
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- Animals, Hemodynamics, Liver enzymology, Liver pathology, Organ Size, Pediatrics, Random Allocation, Swine, Liver Circulation, Liver Transplantation adverse effects, Reperfusion Injury etiology
- Abstract
Background: Ischemia-reperfusion injury is partly responsible for morbidity in pediatric liver transplantation. Large-for-size (LFS) liver transplantation has not been fully studied in the pediatric population, and the effects of reperfusion injury may be underestimated., Materials and Methods: Thirteen Landrace-Large white pigs weighing 23 kg (range, 17-38 kg) underwent orthotopic liver transplantation. They were divided into two groups according to the size of the donor body: LFS and control (CTRL). After transplantation, the abdominal cavity of the recipient was kept open and portal venous flow (PVF) was measured after 1 h. The ratio of recipient PVF (PVFr) to donor PVF was used to establish correlations with ischemia and reperfusion parameters. Liver biopsies were taken 1 h after transplantation to assess ischemia and reperfusion and to quantify the gene expression of endothelial nitric oxide synthase, interleukin 6, BAX, and BCL., Results: Recipient weight, total ischemia time, and warm ischemia time were similar between groups. Among hemodynamic and metabolic analyses, pH, central arteriovenous PCO2 difference, and AST were statistically worse in the LFS group than in the CTRL group. The same was found with endothelial nitric oxide synthase (0.41 ± 0.18 versus 1.56 ± 0.78; P = 0.02) and interleukin 6 (4.66 ± 4.61 versus 16.21 ± 8.25; P = 0.02). In the LFS group, a significant decay in the PVFr was observed in comparison with the CTRL group (0.93 ± 0.08 and 0.52 ± 0.11, respectively; P < 0.001)., Conclusions: The implantation of a graft was responsible for poor hemodynamic status of the recipient 1 h after transplantation. Furthermore, the LFS group demonstrated markers of ischemia and reperfusion that were worse when compared with the CTRL group and exhibited a more significant decrease in PVF from donor to recipient., (Copyright © 2014 Elsevier Inc. All rights reserved.)
- Published
- 2014
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14. Annihilation dynamics of stringlike topological defects in a nematic lyotropic liquid crystal.
- Author
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Guimarães RR, Mendes RS, Fernandes PR, and Mukai H
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- Computer Simulation, Materials Testing, Phase Transition, Temperature, Liquid Crystals chemistry, Models, Chemical, Models, Molecular, Refractometry methods
- Abstract
Topological defects can appear whenever there is some type of ordering. Its ubiquity in nature has been the subject of several studies, from early Universe to condensed matter. In this work, we investigated the annihilation dynamics of defects and antidefects in a lyotropic nematic liquid crystal (ternary mixture of potassium laurate, decanol and deionized-destillated water) using the polarized optical light microscopy technique. We analyzed Schlieren textures with topological defects produced due to a symmetry breaking in the transition of the isotropic to nematic calamitic phase after a temperature quench. As result, we obtained for the distance D between two annihilating defects (defect-antidefect pair), as a function of time t remaining for the annihilation, the scaling law D ∝ t(α), with α = 0.390 and standard deviation σ = 0.085. Our findings go in the direction to extend experimental results related to dynamics of defects in liquid crystals since only thermotropic and polymerics ones had been investigated. In addition, our results are in good quantitative agreement with previous investigations on the subject.
- Published
- 2013
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15. Antipersistent behavior of defects in a lyotropic liquid crystal during annihilation.
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Ribeiro HV, Guimarães RR, Teixeira-Souza RT, Mukai H, Fernandes PR, Lenzi EK, and Mendes RS
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- Computer Simulation, Phase Transition, Liquid Crystals chemistry, Models, Chemical, Models, Molecular, Models, Statistical, Solutions chemistry, Solvents chemistry
- Abstract
We report on the dynamical behavior of defects of strength s=±1/2 in a lyotropic liquid crystal during the annihilation process. By following their positions using time-resolved polarizing microscopy technique, we present statistically significant evidence that the relative velocity between defect pairs is Gaussian distributed, antipersistent, and long-range correlated. We further show that simulations of the Lebwohl-Lasher model reproduce quite well our experimental findings.
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- 2013
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16. A simplified experimental model of large-for-size liver transplantation in pigs.
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Leal AJ, Tannuri AC, Belon AR, Guimarães RR, Coelho MC, Oliveira Gonçalves Jd, Sokol SS, De Melo ES, Otoch JP, and Tannuri U
- Subjects
- Animals, Aspartate Aminotransferases blood, Body Weight, Feasibility Studies, Hemodynamics, Models, Animal, Organ Size, Potassium blood, Reproducibility of Results, Sodium blood, Swine, Time Factors, Liver anatomy & histology, Liver Transplantation methods
- Abstract
Objective: The ideal ratio between liver graft mass and recipient body weight for liver transplantation in small infants is unknown; however, if this ratio is over 4%, a condition called large-for-size may occur. Experimental models of large-for-size liver transplants have not been described in the literature. In addition, orthotopic liver transplantation is marked by high morbidity and mortality rates in animals due to the clamping of the venous splanchnic system. Therefore, the objective of this study was to create a porcine model of large-for-size liver transplantation with clamping of the supraceliac aorta during the anhepatic phase as an alternative to venovenous bypass., Method: Fourteen pigs underwent liver transplantation with whole-liver grafts without venovenous bypass and were divided into two experimental groups: the control group, in which the weights of the donors were similar to the weights of the recipients; and the large-for-size group, in which the weights of the donors were nearly 2 times the weights of the recipients. Hemodynamic data, the results of serum biochemical analyses and histological examination of the transplanted livers were collected., Results: The mortality rate in both groups was 16.5% (1/7). The animals in the large-for-size group had increased serum levels of potassium, sodium, aspartate aminotransferase and alanine aminotransferase after graft reperfusion. The histological analyses revealed that there were no significant differences between the groups., Conclusion: This transplant method is a feasible experimental model of large-for-size liver transplantation.
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- 2013
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17. The role of interleukin-6, endothelins, and apoptotic genes in small bowel transplantation, in a swine model of ischemia and reperfusion injury.
- Author
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de Pinho-Apezzato ML, Maksoud-Filho JG, Valinetti EA, Santos MM, Tannuri AC, Mello ES, Silva LF, de Mendonça Coelho MC, Gibelli NE, Rocha RM, Nonogaki S, Guimarães RR, and Tannuri U
- Subjects
- Animals, Endothelin-1 biosynthesis, Gene Expression Profiling, Gene Expression Regulation, Immunohistochemistry methods, Ischemia pathology, Neutrophils pathology, Swine, bcl-2 Homologous Antagonist-Killer Protein biosynthesis, bcl-X Protein biosynthesis, Apoptosis, Endothelins metabolism, Interleukin-6 metabolism, Intestines transplantation, Reperfusion Injury pathology
- Abstract
IRI is closely related to sepsis in ITx setting. Complete understanding of the mechanisms involved in IRI development may improve outcomes. Ortothopic ITx without immunosuppression was performed in order to characterize IRI-associated mucosal damage. Twenty pigs underwent ITx. Two groups were assigned to different CI times: G1: 90 min and, G2: 180 min. Euro-Collins was used as preservation solution. Jejunal fragments were collected at donor laparotomy, 30 min, and 3 days after reperfusion. IRI assessment involved: histopathologic analysis, quantification of MPO-positive cells through immunohistochemical studies, quantification of epithelial apoptotic cells using TUNEL staining, and quantification of IL-6, ET-1, Bak, and Bcl-XL genes expression by RT-PCR. Neutrophilic infiltration increased in a similar fashion in both groups, but lasted longer in G2. Apoptosis detected by TUNEL staining increased and anti-apoptotic gene Bcl-XL expression decreased significantly in G1, 3 days after surgery. Endothelin-1 and IL-6 genes expression increased 30 min after the procedure and returned to baseline 3 days after surgery. In conclusion, IL-6 and ET-1 are involved precociously in the development of intestinal IRI. Apoptosis was more frequently detected in G1 grafts by TUNEL-staining and by RT-PCR., (© 2011 John Wiley & Sons A/S.)
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- 2011
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18. Which is the best technique for hepatic venous reconstruction in pediatric living-donor liver transplantation? Experience from a single center.
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Tannuri U, Santos MM, Tannuri AC, Gibelli NE, Moreira A, Carnevale FC, Ayoub AA, Maksoud-Filho JG, Andrade WC, Velhote MC, Silva MM, Pinho-Apezzato ML, Miyatani HT, and Guimarães RR
- Subjects
- Adolescent, Adult, Anastomosis, Surgical methods, Child, Child, Preschool, Female, Hepatectomy methods, Hepatic Veno-Occlusive Disease epidemiology, Hepatic Veno-Occlusive Disease etiology, Hospitals, Pediatric statistics & numerical data, Humans, Infant, Male, Middle Aged, Postoperative Complications epidemiology, Postoperative Complications etiology, Prospective Studies, Stents, Treatment Outcome, Young Adult, Hepatic Veins surgery, Hepatic Veno-Occlusive Disease prevention & control, Liver Transplantation methods, Living Donors, Postoperative Complications prevention & control, Vena Cava, Inferior surgery
- Abstract
Background/purpose: The introduction of the piggyback technique for reconstruction of the liver outflow in reduced-size liver transplants for pediatric patients has increased the incidence of hepatic venous outflow block (HVOB). Here, we proposed a new technique for hepatic venous reconstruction in pediatric living-donor liver transplantation., Methods: Three techniques were used: direct anastomosis of the orifice of the donor hepatic veins and the orifice of the recipient hepatic veins (group 1); triangular anastomosis after creating a wide triangular orifice in the recipient inferior vena cava at the confluence of all the hepatic veins (group 2); and a new technique, which is a wide longitudinal anastomosis performed at the anterior wall of the inferior vena cava (group 3)., Results: In groups 1 and 2, the incidences of HVOB were 27.7% and 5.7%, respectively. In group 3, no patient presented HVOB (P = .001). No difference was noted between groups 2 and 3., Conclusions: Hepatic venous reconstruction in pediatric living-donor liver transplantation must be preferentially performed by using a wide longitudinal incision at the anterior wall of the recipient inferior vena cava. As an alternative technique, triangulation of the recipient inferior vena cava, including the orifices of the 3 hepatic veins, may be used., (Copyright © 2011 Elsevier Inc. All rights reserved.)
- Published
- 2011
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19. Colon mucinous adenocarcinoma in childhood: a case report with emphasis on image findings.
- Author
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Muccillo A, Marchiori E, Penna CR, Guimarães RR, Zanetti G, Abdalla G, Ventura N, Constantino CL, Pereira ML, Brandão V, Martins P, Canellas R, and Varella de Oliveira R
- Abstract
Colorectal cancer is extremely rare in children. We report a case of a 12-year-old boy who presented with a five-month history of weight loss and anorexia, associated with vomiting episodes, dizziness, fatigue, and dyspnea. On physical examination, a palpable abdominal mass was noticed on the right hypochondrium and flank. An imaging study was performed, which showed a solid mass on the right colon. The patient underwent incisional surgical biopsy, and subsequent histopathologic analysis revealed a colon mucinous adenocarcinoma.
- Published
- 2010
- Full Text
- View/download PDF
20. [Register of Aphaereta laeviuscula (Spinola) (Hymenoptera: Braconidae) and Nasonia vitripennis (Walker) (Hymenoptera: Pteromalidae) as parasitoids of Cochliomyia hominivorax (Coquerel) (Diptera: Calliphoridae), in the State of Rio de Janeiro, Brazil].
- Author
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Rodrigues-Guimarães R, Guimarães RR, Carvalho RW, Mayhé-Nunes AJ, and Moya-Borja GE
- Subjects
- Animals, Brazil, Diptera parasitology, Hymenoptera physiology
- Abstract
The captures occurred between January and December of 2004 in urban area in the city of Nova Iguaçu, the rural area of the city of Seropédica and in a forest area in the Biological Reserve of the Tinguá, Nova Iguaçu State of Rio de Janeiro. The total of 1,528 larvae of Cochliomyia hominivorax (Coquerel) were used as bait, 505 in the urban area, 556 in rural and the 467 in the forest one. The indices of Synantropic, Coefficient of Constancy, the risk (Odds Ratio) of parasitism between the areas was calculated, prevalence and parasitic intensity. The percentage of emergence was of 46.6%. Aphaereta laeviuscula (Spinola) was captured only in rural environment; its indices were: Synantropic I. = +50, c. constancy = 25%, prevalence = 0.72% and I. parasitic = 44.5; already Nasonia vitripennis (Walker) was captured in the areas rural and urban and the indices had been: synanthropy = +98, constancy = 58.3%, Odds Ratio = IC95% = 0,025 < micro > 0.27, P < 0,05, prevalence = 3.2% and parasitic intensity = 7.35. The risk of parasitism for N. vitripennis in urban areas is high. The occurrence of A. laeviuscula as parasitic of C. hominivorax is registered in the State of Rio de Janeiro.
- Published
- 2006
- Full Text
- View/download PDF
21. [Thoracic radiologic aspects in paracoccidioidomycosis].
- Author
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do Valle AC, Guimarães RR, Lopes DJ, and Capone D
- Subjects
- Adult, Aged, Aged, 80 and over, Female, Humans, Lung Diseases, Fungal complications, Male, Middle Aged, Paracoccidioidomycosis complications, Radiography, Retrospective Studies, Tuberculosis, Pulmonary diagnostic imaging, Lung diagnostic imaging, Lung Diseases, Fungal diagnostic imaging, Paracoccidioidomycosis diagnostic imaging
- Abstract
In this paper the authors analyse 159 radiographs from paracoccidioidomycosis patients seen at the Evandro Chagas Hospital/Fiocruz in the period between January 1960 to December 1988. Twenty four cases (15.09%) of association with tuberculosis were observed; one with pneumoconiosis; one with aspergillosis, and two with carcinoma. Twenty cases were excluded from the radiologic analysis: in 8 of these the diagnosis of tuberculosis occurred concomitantly, and in 12 patients, lung fibrosis due to previous treatment for tuberculosis or paracoccidioidomycosis was present in the 139 remaining cases, the radiographic abnormalities encountered were grouped according to the predominance of lesions at the various lung sites, if alveolar or interstitial, according to Magalhães' (1982) classification modified by the authors: infiltrate 55 cases (39.6%); mist 28 (20.1%); pneumonic 23 (16.6%); nodular 16 (11.5%); micronodular 10 (7.2%), and fibrotic 7 (5.0%). In 113 cases it was possible to follow the regression of the pulmonary process radiologically. In 85 (75.2%) patients, regression took place within 6 months; in 17 (15.0%) cases between 7 and 12 months; in 4 (3.5%) between 13 and 24 months, and in 7 (6.1%) cases no changes in the radiographic pattern were noted.
- Published
- 1992
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