Efeito da claritromicina na celularidade do lavado broncoalveolar em camundongos com doença pulmonar neutrofílica induzida

OBJECTIVE: Macrolide antibiotics have anti-inflammatory properties in lung diseases. The aim of this study was to investigate the effect of clarithromycin in pulmonary cellular inflammatory response in mice. METHOD: Eight adult Swiss mice were studied. All animals received an intranasal challenge (80 µL) with dead Pseudomonas aeruginosa (1.0 x 10(12) CFU/mL). Bronchoalveolar lavage was performed 2 days later, with total cell count and differential cell analysis. The study group (n = 4) received clarithromycin treatment (50 mg/kg/day, intraperitoneal) for 5 days. Treatment was initiated 2 days before intranasal challenge. RESULTS: There was no significant difference in total cell count between the groups (mean: 2.0 x 10(6) and 1.3 x 10(6), respectively). In both groups, there was a predominance of neutrophils. However, the study group had a higher percentage of lymphocytes in the bronchoalveolar lavage than the control group (median of 19% vs 2.5%, P = .029). CONCLUSION: Clarithromycin alters the cytological pattern of bronchoalveolar lavage of Swiss mice with neutrophil pulmonary inflammation, significantly increasing the percentage of lymphocytes.OBJETIVO: Os antibióticos macrolídeos podem apresentar um efeito antiinflamatório em doenças pulmonares. O objetivo deste estudo é investigar o efeito da claritromicina na resposta inflamatória celular pulmonar em camundongos Swiss. MÉTODO: Foram utilizados 8 camundongos Swiss adultos (6-8 semanas). Todos os animais receberam um desafio intranasal (80 µL) com Pseudomonas aeruginosa mortas (1 x 10(12) UFC/mL). Dois dias após o desafio, foi realizado lavado broncoalveolar (LBA) com contagem total de células (CTC) e exame citológico diferencial. O grupo em estudo (n=4) recebeu tratamento com claritromicina (50mg/kg/dia, intraperitoneal) por 5 dias, sendo iniciado o tratamento 2 dias antes do desafio intranasal. O grupo controle (n=4) não recebeu tratamento com claritromicina. RESULTADOS: Não houve diferença significativa na CTC entre os grupos (média de 2x10(6) e 1,3x10(6), respectivamente). Em ambos os grupos, houve predomínio absoluto de neutrófilos. Contudo, o grupo tratado com claritromicina, apresentou um número percentual significativamente maior de linfócitos no LBA (mediana de 2,5% vs 19%, p=0,029). CONCLUSÃO: O uso de claritromicina altera o exame citológico diferencial do lavado bronco-alveolar de camundongos Swiss com inflamação pulmonar neutrofílica, aumentando significativamente o número percentual de linfócitos

Experimental model of spinal cord injury in rats with a device for local therapeutic agents access

An experimental model of spinal cord injury at a precise and reproducible site is an extremely important tool for studying new therapies in spinal cord injuries. OBJECTIVES: To develop an experimental model of spinal cord injury in rats that is able to produce a complete injury (paraplegia) and placing a system enabling agents access close to injury site in order to test local therapeutic agents. METHODS: Fifteen Wistar rats were submitted to surgical transection of the spine, performed by using scissors at the level of T-13 to L-3 vertebral bodies, and, at the end of the procedure, to the insertion of a subdermal catheter intended to enable local therapeutic agents access to injury site. RESULTS: An experimental model of paraplegia was consistently developed by adding a supplementary catheter for local therapeutic agents access to injury site. CONCLUSION: An animal model of spinal cord injury and a system for local therapeutic agents access can be reproduced for the study of different modifiers of the regenerative response in a model of rats with spinal cord injury.Um modelo experimental de lesão raquimedular com localização precisa e reproduzível é uma ferramenta extremamente importante para o estudo de novas terapias em lesões raquimedulares. OBJETIVOS: Desenvolver um modelo experimental de lesão raquimedular em ratos que produza lesão completa (paraplegia) com o posicionamento de um sistema que permita o acesso de agentes próximo ao local da lesão para testar agentes terapêuticos locais. MÉTODOS: Quinze ratos Wistar foram submetidos à transecção cirúrgica da medula espinhal, realizada com o uso de tesoura ao nível dos corpos vertebrais de T-13 a L-3 e, ao final do procedimento, à implantação de um cateter subcutâneo para o acesso de agentes terapêuticos locais ao local da lesão. RESULTADOS: Um modelo experimental de paraplegia foi consistentemente desenvolvido com a adição suplementar de um cateter para o acesso de agentes terapêuticos locais ao local da lesão. CONCLUSÃO: Um modelo animal de lesão raquimedular e um sistema para o acesso de agentes terapêuticos locais pode ser reproduzido para o estudo de diferentes modificadores da resposta regenerativa em um modelo de ratos com lesão raquimedular.UNIFESPUNIFESPSciEL

Oral manifestations, counts of CD4+ T lymphocytes and viral load in Brazilian and American HIV-infected children

A prevalência de manifestações estomatológicas associadas à infecção pelo HIV foi avaliada em 184 crianças de ambos os sexos, da faixa etária de zero a 13 anos de idade, atendidas nos Ambulatórios de AIDS Pediátrica do Hospital São Lucas (HSL) da PUCRS, e do Hospital de Clínicas de Porto Alegre (HCPA) da UFRGS, ambos em Porto Alegre, RS, Brasil e no Centro Pediátrico para Doenças Infecciosas do Hospital Universitário e Departamento de Odontopediatria da Faculdade de Odontologia da Universidade Estadual de Nova Iorque (SUNY) em Stony Brook, Nova Iorque, EUA, no período de janeiro de 1999 a maio de 2000. A freqüência de crianças brasileiras (72,73%) e norte-americanas (53,66%) com manifestações estomatológicas associadas à infecção pelo HIV foi estatisticamente significativa, com destaque para linfadenopatia cérvico-facial, aumento de volume das parótidas, candidíase eritematosa, petéquias, gengivite, xerostomia e queilite angular. As crianças com manifestações estomatológicas apresentaram contagens médias de linfócitos T-CD4+ próximas à normalidade e carga viral alta.Oral manifestations related to HIV infection were evaluated in 184 children of both genders, aging 0-13 years. The oral exams were carried out at the Ambulatory of Pediatric AIDS, São Lucas Hospital and at the Clinics Hospital, both in Porto Alegre, RS, Brazil, and at the University Hospital and School of Dentistry, State University of New York, Stony Brook, NY, USA, from January 1999 to May 2000. A high prevalence of oral manifestations was observed both in Brazilian (72.73%) and American (53.66%) children. The most frequent manifestations were cervical lymphadenopathy, swelling of the parotids, erythematous candidiasis, petechia, gingivitis, xerostomia and angular cheilitis. Children with oral manifestations had almost normal counts of CD4+ T lymphocytes and high viral load

Hepcidin serum levels in HCV chronically mono-infected naïve patients, compared to healthy individuals

Introduction: Metabolism of iron is altered in patients infected with chronically Hepatitis C. The aim of this study is to compare compare the hepcidin levels in between individuais chronically infected with HCV and uninfected individuals. The aim of this study is to compare the hepcidin serum levels between individuals chronically infected with HCV and uninfected individuals. Methods: A cross-sectional study evaluating hepcidin serum levels of mono-infected HCV (n=29), naive, non-diabetic, non-cirrhotic and non-obese patients by means of ELISA, compared to uninfected patients (n=9) with the same characteristics. The degree of liver fibrosis, according to the METAVIR scale on liver biopsies, the lipid profile, the resistance insulin level, as calculated on HOMA-IR (homeostatic model assessment for insulin resistance), the interleukin-6 (IL-6) and the ferritin serum levels were also measured. Results: The levels of hepcidin were significantly lower in HCV patients compared to controls (8.4 pg/mL (±4.94) vs. 19.51 pg/mL (±5.51)) with p<0.001. The levels of ferritin and hepcidin did not show any relation. There was no difference between hepcidin levels in relation to viral genotype, viral load, IL-6 and degrees of fibrosis within HCV infected individuals. Conclusion: It is possible that hepatic iron overload in this population is explained by suppressed levels of hepcidin in patients with HCV. Keywords: Hepcidin; HCV; interleukin-6 (IL-6); mono-infecte

A new waterborne chitosan-based polyurethane hydrogel as a vehicle to transplant bone marrow mesenchymal cells improved wound healing of ulcers in a diabetic rat model

[EN] Foot ulcers, a common complication of diabetes, can cause physical incapacity and are derived from several factors, including poor wound healing. New therapeutic strategies are needed to minimize this complication for the sake of patients' health. We therefore developed a new chitosan- polyurethane hydrogel membrane (HPUC) and the WA results confirmed that HPUC present low cytotoxicity and improved wound healing when used with mononuclear bone marrow fraction cells in the diabetic rat model. The biodegradable hydrogels were produced in block copolymer networks with a combination of chitosan blocks and biodegradable polyurethane. The membranes were characterized by FTIR, C-13-NMR and thermogravimetry. Swelling and hydrolytic degradation were also evaluated. The non-solubility of the membranes in good solvents and the chemical characterization confirmed that the network structure was formed between the PU and the chitosan through urea/urethane bonds. The findings confirm that the HPUC have interesting properties that make them suitable for wound healing applications.This work was funded by: Coordenacao de Aperfeicoamento de Pessoal de Nivel Superior -doctoral fellowships to Viezzer, C (CAPES/PDSE-BEX: 1408/11-9) and the Spanish Ministry of Economy and Competitiveness (MINECO) through the MAT2016-76039-C4-1-R Project, including FEDER financial support. CIBER-BBN is an initiative funded by the VI National R&D&i Plan 2008-2011, Iniciativa Ingenio 2010, Consolider Program, CIBER Actions and financed by the Instituto de Salud Carlos III with assistance from the European Regional Development Fund.Viezzer, C.; Mazzuca, R.; Machado, DC.; Forte, MMDC.; Gómez Ribelles, JL. (2020). A new waterborne chitosan-based polyurethane hydrogel as a vehicle to transplant bone marrow mesenchymal cells improved wound healing of ulcers in a diabetic rat model. 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