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81.
Natália C.C.A Fernandes Juliana S. Nogueira Rodrigo A. Réssio Cinthya S. Cirqueira Lidia M. Kimura Karolina R. Fernandes Mariana S. Cunha Renato P. Souza Juliana M. Guerra 《Experimental and toxicologic pathology》2017,69(2):63-71
A widespread epidemic of Zika virus (ZIKV) infection was reported in 2015 in South and Central America, with neurological symptons including meningoencephalitis and Guillain-Barré syndrome in adults, besides an apparent increased incidence of microcephaly in infants born to infected mothers. It is becoming a necessity to have a trustworthy animal model to better understand ZIKV infection. In this study we used newborn white Swiss mice as a model to investigate the ZIKV strain recently isolated in Brazil. ZIKV was inoculated via intracerebral and subcutaneous routes and analysed through gross histopathology and immunohistochemistry. Here we demonstrated first that the intracerebral group (ICG) displayed severe cerebral lesions, with neuronal death, presence of apoptotic bodies, white matter degeneration and neutrophil perivascular cuffing. In the subcutaneous group (SCG), we observed moderate cerebral lesions, morphologically similar to that found in ICG and additional myelopathy, with architectural loss, marked by neuronal death and apoptotic bodies. Interestingly, we found an intense astrogliosis in brain of both groups, with increased immunoexpression of GFAP (glial fibrillary acidic protein) and presence of hypertrophic astrocytes. The spinal cord of subcutaneous group (SCG) exhibited reduction of astrocytes, but those positive for GFAP were hypertrophic and presented prolonged cellular processes. Finally significant lesions in the central nervous system (CNS) were present in newborn mice inoculated by both routes, but SCG method led to an important neurological manifestations (including myelopathy), during a longer period of time and appears for us to be a better model for ZIKV infection. 相似文献
82.
Silvia Cristina Núñez Cristiane Miranda França Daniela Fátima Teixeira Silva Gessé Eduardo Calvo Nogueira Renato Araujo Prates Martha Simões Ribeiro 《Lasers in medical science》2013,28(2):633-641
Low-level laser therapy (LLLT) promotes biomodulation of wound healing and literature reports that light delivery during the inflammation could play a different role compared with latter phases of the healing process. The objective of this study was to investigate whether single dose of a red laser (λ?=?660 nm) is different from fractionated delivery protocol in full thickness burns. Two lesions were inflicted on the back of 36 rats. In the fractionated dose group (FG), the lesions were irradiated with 1 J/cm² on days 1, 3, 8, and 10 post-wounding. In the single dose group (SG), the lesions were irradiated with 4 J/cm² on day 1, immediately after injury. Control lesions (CG) received no light and were left to heal spontaneously. Blood flow was measured on days 1, 3, 8, 10, 15, and 21 using laser Doppler flowmetry. Animals were killed on days 3, 8, 10, 15, and 21. Skin specimens were obtained and routinely processed for hematoxylin and eosin. The specimens were evaluated according to differential leukocyte counting and angiogenesis. Statistical analysis was performed, and significance was accepted at p?<?0.05. Irradiated groups showed a peak of new vessels on day 15 while, for CG, the peak was on day 21. On day 21, FG exhibited a significantly greater number of cumulative neutrophils while SG showed a higher number of mononuclear cells. Our results confirm that both protocols used accelerate angiogenesis and stimulate leukocyte chemotaxis on burn treatment. In addition, this work suggests that a single-dose LLLT accelerates the inflammatory phase of skin repair. 相似文献
83.
C. Quintaneiro M. Monteiro A. M. V. M. Soares J. Ranville A. J. A. Nogueira 《Ecotoxicology (London, England)》2014,23(3):449-458
Metals are released into freshwater ecosystems from natural and anthropogenic sources, compromising their structural and functional equilibrium. As early warning tools, cholinesterases (ChEs) are usually used to assess the effects of organophosphate and carbamate pesticides, but are also known to be inhibited by metals. The objectives of this work were to characterise the activity of ChE present in the amphipod Echinogammarus meridionalis and the shrimp Atyaephyra desmarestii and to evaluate the in vivo effects of the metals copper and zinc in their ChE activity. To achieve this, firstly the activity of ChE forms were characterised using different in vitro assays with substrates and selective inhibitors. Then, the in vivo effects of 48 h exposures to increasing concentrations of copper and zinc on ChE activity were determined. The ChE form present in both species was acetylcholinesterase (AChE) since both revealed preference for the acetylthiocholine iodide substrate, total inhibition with eserine, the inhibitor of ChEs, and with 1,5-bis(4-allyldimethylammoniumphenyl)-pentan-3-one dibromide, the specific inhibitor of AChE, and presented insensitivity to iso-OMPA, a specific inhibitor of butyrylcholinesterase. The activity of ChEs was inhibited by zinc exposures in the amphipod species, but was not affected by copper. Exposure to copper and zinc did not affect ChEs activity in the shrimp at the concentrations tested. This work is a relevant contribution as foundation for the use of AChE in freshwater crustaceans in further studies including biomonitoring campaigns in different contamination scenarios. 相似文献
84.
85.
Karina Azzolin Claudia Motta Mussi Karen Brasil Ruschel Emiliane Nogueira de Souza Amália de Fátima Lucena Eneida Rejane Rabelo-Silva 《Applied Nursing Research》2013,26(4):239-244
ObjectiveThe objective of the study is to evaluate the effectiveness of nursing interventions (NIC) using nursing outcomes (NOC) and based on NANDA-I nursing diagnoses in patients with heart failure in home care.MethodIn this longitudinal study, 23 patients with heart failure were followed for 6 months, in four home visits. During the visits, nursing diagnoses were established, outcomes assessed, and interventions implemented.ResultsOf the 11 NIC interventions implemented, eight proved effective, that is, showed significant improvement between the first and the fourth visit, according to scores obtained for six outcomes: knowledge: treatment regimen, knowledge: medication, compliance behavior, symptom control, activity tolerance, and energy conservation.ConclusionNIC interventions health education, self-modification assistance, behavior modification, teaching: prescribed medication, teaching: disease process, nutritional counseling, telephone consultation, and energy conservation showed effective outcomes based on NOC scores, suggesting that the NANDA-I, NIC, and NOC linkage is useful in patients with heart failure in home care. 相似文献
86.
Beatriz Deoti e Silva Rodrigues Raniere dos Santos Magda Maria Profeta da Luz Flávia Chaves e Silva Igor Guedes Nogueira Reis 《Clinical journal of gastroenterology》2016,9(6):341-344
Acute esophageal necrosis (AEN) or “black esophagus” is a rare condition presented by patients with critical state of health and characterized by a darkened esophagus, usually the distal third, in upper digestive endoscopy. The main clinical manifestation is upper gastrointestinal bleeding and there may be abdominal pain, dysphagia, nausea, vomiting, fever and syncope associated. The diagnosis depends on clinical suspicion and performing endoscopy, the biopsy not being required. In this article we present a case of a patient who had lots of comorbidities and developed AEN during a post-operative period, and discuss the importance of AEN in an increasingly ageing population. 相似文献
87.
Fernanda Souza de Menezes Heitor Pons Leite Paulo Cesar Koch Nogueira 《Nutrition (Burbank, Los Angeles County, Calif.)》2013,29(1):76-80
ObjectiveChildren admitted to the intensive care unit (ICU) are at risk of inadequate energy intake. Although studies have identified factors contributing to an inadequate energy supply in critically ill children, they did not take into consideration the length of time during which patients received their estimated energy requirements after having achieved a satisfactory energy intake. This study aimed to identify factors associated with the non-attainment of estimated energy requirements and consider the time this energy intake is maintained.MethodsThis was a prospective study involving 207 children hospitalized in the ICU who were receiving enteral and/or parenteral nutrition. The outcome variable studied was whether 90% of the estimated basal metabolic rate was maintained for at least half of the ICU stay (satisfactory energy intake). The exposure variables for outcome were gender, age, diagnosis, use of vasopressors, malnutrition, route of nutritional support, and Pediatric Index of Mortality and Pediatric Logistic Organ Dysfunction scores.ResultsSatisfactory energy intake was attained by 20.8% of the patients, within a mean time of 5.07 ± 2.48 d. In a multivariable analysis, a diagnosis of heart disease (odds ratio 3.62, 95% confidence interval 1.03–12.68, P = 0.045) increased the risk of insufficient energy intake, whereas malnutrition (odds ratio 0.43, 95% confidence interval 0.20–0.92, P = 0.030) and the use of parenteral nutrition (odds ratio 0.34, 95% confidence interval 0.15–0.77, P = 0.001) were protective factors against this outcome.ConclusionA satisfactory energy intake was reached by a small proportion of patients during their ICU stay. Heart disease was an independent risk factor for the non-attainment of satisfactory energy intake, whereas malnutrition and the use of parenteral nutrition were protective factors against this outcome. 相似文献
88.
89.
Global vascular expression of murine CD34, a sialomucin-like endothelial ligand for L-selectin 总被引:19,自引:2,他引:19
Extravasation of leukocytes into organized lymphoid tissues and into sites of inflammation is critical to immune surveillance. Leukocyte migration to peripheral lymph nodes (PLN), mesenteric lymph nodes (MLN) and Peyer's patches (PP) depends on L-selectin, which recognizes carbohydrate-bearing, sialomucin-like endothelial cell surface glycoproteins. Two of these ligands have been identified at the molecular level. One is the potentially soluble mucin, GlyCAM 1, which is almost exclusively produced by high endothelial venules (HEV) of PLN and MLN. The second HEV ligand for L-selectin is the membrane-bound sialomucin CD34. Historically, this molecule has been successfully used to purify human pluripotent bone marrow stem cells, and limited data suggest that human CD34 is present on the vascular endothelium of several organs. Here we describe a comprehensive analysis of the vascular expression of CD34 in murine tissues using a highly specific antimurine CD34 polyclonal antibody. CD34 was detected on vessels in all organs examined and was expressed during pancreatic and skin inflammatory episodes. A subset of HEV-like vessels in the inflamed pancreas of nonobese diabetic (NOD) mice are positive for both CD34 and GlyCAM 1, and bind to an L-selectin/immunoglobulin G (IgG) chimeric probe. Finally, we found that CD34 is present on vessels of deafferentiated PLN, despite the fact that these vessels are no longer able to interact with L-selectin or support lymphocyte binding in vitro or trafficking in vivo. Our data suggest that the regulation of posttranslational carbohydrate modifications of CD34 is critical in determining its capability to act as an L-selectin ligand. Based on its ubiquitous expression, we propose that an appropriately glycosylated form of vascular CD34 may act as a ligand for L-selectin-mediated leukocyte trafficking to both lymphoid and nonlymphoid sites. 相似文献
90.
Viral respiratory infection in Curitiba, Southern Brazil 总被引:1,自引:0,他引:1