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41.
Identification of T lymphocytes in human mixed hemopoietic colonies 总被引:11,自引:0,他引:11
The addition of a T-cell growth-promoting medium (PHA-TCM) to culture conditions that support growth of multi-lineage hemopoietic colonies enhances the proliferation of cells with lymphoid morphology within these colonies. These cells were identified as T lymphocytes by their ability to form rosettes with SRBC and their reaction with monoclonal antibodies (OKT3, OKT4) directed against T-cell-specific surface components. They continue to proliferate extensively under the influence of PHA-TCM after transfer of mixed colonies into liquid suspension culture. Supportive evidence for a common progenitor of myeloid and lymphoid cells within single mixed colonies is provided by Y-chromatin body analysis of E-rosette positive and negative cells in colonies grown in cocultures of male and female bone marrow cells. 相似文献
42.
Reversal of granulocyte adherence to nylon fibers using local anesthetic agents: possible application to filtration leukapheresis 总被引:1,自引:0,他引:1
The effects of the cationic anesthetic agents tetracaine and lidocaine on granulocyte function, morphology, and adherence to nylon fibers were studied in an attempt to improve current methods of granulocyte collection by filtration leukapheresis (FL). When dissolved in acid- citrate-dextrose (ACD) plasma, these drugs significantly increased granulocyte elution from the fibers in a dose-related fashion. Granulocytes exposed to tetracaine and lidocaine remained more than 95% viable, retained normal bactericidal capacity after the drugs were washed from the cells, and had preserved membrane integrity, as evidenced by the normal ultrastructural appearance of tetracaine- exposed cells and an absence of leakage of lysozyme or lactic dehydrogenase. Granulocytes eluted with the anesthetic agents were rounded in shape with a reduction in the number of filopodial cytoplasmic projections and a relative absence of cytoplasmic vacuolization when compared to granulocytes eluted with ACD plasma alone. Dose-related inhibition of phagocytosis and adherence, which was largely reversible after washing the granulocytes, was noted. Greater than 95% of the lidocaine could be removed from the eluate with a single centrifugation and resuspension, indicating that granulocytes prepared by FL with anesthetic-enhanced elution could be potentially transfusable. 相似文献
43.
Diesel exhaust particulates affect cell signaling,mucin profiles,and apoptosis in trachea explants of Balb/C mice 下载免费PDF全文
Robson Seriani Mara de Souza Junqueira Alessandra Choqueta de Toledo Milton Arruda Martins Marcelo Seckler Adriano Mesquita Alencar Elnara Marcia Negri Luiz Fernando Ferraz Silva Thaís Mauad Paulo Hilário Nascimento Saldiva Mariangela Macchione 《Environmental toxicology》2015,30(11):1297-1308
Particulate matter from diesel exhaust (DEP) has toxic properties and can activate intracellular signaling pathways and induce metabolic changes. This study was conducted to evaluate the activation of extracellular signal‐regulated kinase (ERK) and c‐Jun N‐terminal kinase (JNK) and to analyze the mucin profile (acid (AB+), neutral (PAS+), or mixed (AB/PAS+) mucus) and vacuolization (V) of tracheal explants after treatment with 50 or 100 μg/mL DEP for 30 or 60 min. Western blot analyses showed small increases in ERK1/2 and JNK phosphorylation after 30 min of 100 μg/mL DEP treatment compared with the control. An increase in JNK phosphorylation was observed after 60 min of treatment with 50 μg/mL DEP compared with the control. We did not observe any change in the level of ERK1/2 phosphorylation after treatment with 50 μg/mL DEP. Other groups of tracheas were subjected to histological sectioning and stained with periodic acid‐Schiff (PAS) reagent and Alcian Blue (AB). The stained tissue sections were then subjected to morphometric analysis. The results obtained were compared using ANOVA. Treatment with 50 μg/mL DEP for 30 min or 60 min showed a significant increase (p < 0.001) in the amount of acid mucus, a reduction in neutral mucus, a significant reduction in mixed mucus, and greater vacuolization. Our results suggest that compounds found in DEPs are able to activate acid mucus production and enhance vacuolization and cell signaling pathways, which can lead to airway diseases. © 2014 Wiley Periodicals, Inc. Environ Toxicol 30: 1297–1308, 2015. 相似文献
44.
Marcos Araújo Castro e Silva Tiago Ferraz Maria Ctira Bortolini David Comas Tbita Hünemeier 《Proceedings of the National Academy of Sciences of the United States of America》2021,118(14)
Different models have been proposed to elucidate the origins of the founding populations of America, along with the number of migratory waves and routes used by these first explorers. Settlements, both along the Pacific coast and on land, have been evidenced in genetic and archeological studies. However, the number of migratory waves and the origin of immigrants are still controversial topics. Here, we show the Australasian genetic signal is present in the Pacific coast region, indicating a more widespread signal distribution within South America and implicating an ancient contact between Pacific and Amazonian dwellers. We demonstrate that the Australasian population contribution was introduced in South America through the Pacific coastal route before the formation of the Amazonian branch, likely in the ancient coastal Pacific/Amazonian population. In addition, we detected a significant amount of interpopulation and intrapopulation variation in this genetic signal in South America. This study elucidates the genetic relationships of different ancestral components in the initial settlement of South America and proposes that the migratory route used by migrants who carried the Australasian ancestry led to the absence of this signal in the populations of Central and North America. 相似文献
45.
Daniel Dominguez Ferraz Karen Valadares Trippo Gabriel Pereira Duarte Mansueto Gomes Neto Kionna Oliveira Bernardes Santos Jamary Oliveira Filho 《Archives of physical medicine and rehabilitation》2018,99(5):826-833
Objectives
To compare the effects of functional training, bicycle exercise, and exergaming on walking capacity of elderly with Parkinson disease (PD).Design
A pilot randomized, controlled, single-blinded trial.Setting
A state reference health care center for elderly, a public reference outpatient clinic for the elderly.Participants
Elderly individuals (≥60 years of age; N=62) with idiopathic PD (stage 2 to 3 of modified Hoehn and Yahr staging scale) according to the London Brain Bank.Intervention
The participants were randomly assigned to three groups. Group 1 (G1) participated in functional training (n=22); group 2 (G2) performed bicycle exercise (n=20), and group 3 (G3) trained with Kinect Adventures (Microsoft, Redmond, WA) exergames (n=20).Main Outcome Measures
The primary outcome measure was the 6-minute walk test (6MWT); secondary outcome measures were the 10-m walk test (10MWT), sitting-rising test (SRT), body mass index, Parkinson Disease Questionnaire-39, World Health Organization Disability Assessment Schedule 2.0 (WHODAS 2.0), and 15-item Geriatric Depression Scale.Results
All groups showed significant improvements in 6MWT (G1 P=.008; G2 P=.001; G3 P=.005), SRT (G1 P<.001; G2 P=.001; G3 P=.003), and WHODAS 2.0 (G1 P=.018; G2 P=.019; G3 P=.041). Only G3 improved gait speed in 10MWT (P=.11). G1 (P=.014) and G3 (P=.004) improved quality of life. No difference was found between groups.Conclusions
Eight weeks of exergaming can improve the walking capacity of elderly patients with PD. Exergame training had similar outcomes compared with functional training and bicycle exercise. The three physical exercise modalities presented significant improvements on walking capacity, ability to stand up and sit, and functionality of the participants. 相似文献46.
Ferraz Ana Paula Seara Fernando A. C. Baptista Emanuelle F. Barenco Thais S. Sottani Thais B. B. Souza Natalia S. C. Domingos Ainá E. Barbosa Raiana A. Q. Takiya Christina M. Couto Marcos T. Resende Gabriel O. Campos de Carvalho Antonio C. Ponte Cristiano G. Nascimento Jose Hamilton M. 《Cardiovascular drugs and therapy / sponsored by the International Society of Cardiovascular Pharmacotherapy》2021,35(4):719-732
Cardiovascular Drugs and Therapy - In the present study, the therapeutic efficacy of a selective BKCa channel opener (compound X) in the treatment of monocrotaline (MCT)-induced pulmonary arterial... 相似文献
47.
Role of gamma-glutamyl transferase activity in patients with chronic hepatitis C virus infection 总被引:2,自引:0,他引:2
Silva IS Ferraz ML Perez RM Lanzoni VP Figueiredo VM Silva AE 《Journal of gastroenterology and hepatology》2004,19(3):314-318
BACKGROUND: Increased serum gamma-glutamyl transferase (GGT) levels are frequently observed in chronic hepatitis C virus (HCV) infection. However, the significance of this finding remains unclear. The purpose of the present paper was to assess the relationship between GGT levels and clinical, biochemical and histological features in chronic HCV-infected carriers. METHODS: Patients with a liver biopsy presenting anti-HCV and HCV-RNA were evaluated. Age, gender, risk factors of transmission, serum alanine aminotransferase (ALT), GGT and alkaline phosphatase (ALP) levels and histological features were assessed in all. Data were analyzed statistically by the chi2 test and multivariate logistic regression analysis. RESULTS: Among 201 patients studied, elevated GGT levels and bile duct damage were observed in 48% and 35% of them, respectively. No association was seen between GGT level and bile duct damage or between GGT level and hepatic steatosis. Initially, age >40 years (P=0.007), elevated ALT (P=0.01), grading of inflammatory activity (P=0.004) and staging of fibrosis (P<0.001) were found to be associated with elevated GGT levels. After multivariate regression analysis, histology grading 3 and 4 inflammation activity (P=0.01) and staging 3 and 4 fibrosis (P=0.01) remained independently associated with elevated GGT level. CONCLUSIONS: A significant number of patients with chronic HCV infection had elevated serum GGT levels. Furthermore, this enzyme seemed to be useful as an indirect marker of more advanced liver disease in chronic hepatitis C. 相似文献
48.
Ana Maria Passos Tiago Pires Heringer José Osmar Medina‐Pestana Maria Lucia Gomes Ferraz Celso Francisco Hernandes Granato 《Journal of medical virology》2013,85(4):615-619
Hepatitis E virus (HEV) causes acute and chronic hepatitis in organ transplant recipients. Serological evidence for HEV infection has been discovered in various population groups in Brazil, and a single acute case has been confirmed. To date, however, no cases of HEV infection in immunocompromised patients have been reported in Brazil. This study aimed to identify and characterize hepatitis E cases in renal transplant recipients in Brazil. A retrospective study was performed on 96 serum samples from renal transplant recipients with unexplained liver enzymes elevation. Three confirmed cases of HEV infection were identified that lacked seroconversion to HEV IgG antibodies. The prevalence of HEV in these patients was 3.1%. Using a sequence analysis of a 304‐nucleotide fragment within ORF2, the strains were classified as genotype 3 with a low percent identity to previously characterized strains. This is the first report of hepatitis E infection in renal transplant recipients in Brazil, and the data indicate that a novel genotype 3 subvariant may be present and that further investigation is necessary to characterize the circulating HEV strains. In this setting, HEV infection should be considered as a potential cause of abnormal liver tests of unknown origin. J. Med. Virol. 85:615–619, 2013. © 2013 Wiley Periodicals, Inc. 相似文献
49.
Mark P Maskery Christian Holscher Stephanie P Jones Christopher I Price W David Strain Caroline L Watkins David J Werring Hedley CA Emsley 《Journal of cerebral blood flow and metabolism》2021,41(1):14
Stroke mortality and morbidity is expected to rise. Despite considerable recent advances within acute ischemic stroke treatment, scope remains for development of widely applicable neuroprotective agents. Glucagon-like peptide-1 receptor agonists (GLP-1RAs), originally licensed for the management of Type 2 Diabetes Mellitus, have demonstrated pre-clinical neuroprotective efficacy in a range of neurodegenerative conditions. This systematic scoping review reports the pre-clinical basis of GLP-1RAs as neuroprotective agents in acute ischemic stroke and their translation into clinical trials. We included 35 pre-clinical studies, 11 retrospective database studies, 7 cardiovascular outcome trials and 4 prospective clinical studies. Pre-clinical neuroprotection was demonstrated in normoglycemic models when administration was delayed by up to 24 h following stroke induction. Outcomes included reduced infarct volume, apoptosis, oxidative stress and inflammation alongside increased neurogenesis, angiogenesis and cerebral blood flow. Improved neurological function and a trend towards increased survival were also reported. Cardiovascular outcomes trials reported a significant reduction in stroke incidence with semaglutide and dulaglutide. Retrospective database studies show a trend towards neuroprotection. Prospective interventional clinical trials are on-going, but initial indicators of safety and tolerability are favourable. Ultimately, we propose that repurposing GLP-1RAs is potentially advantageous but appropriately designed trials are needed to determine clinical efficacy and cost-effectiveness. 相似文献
50.
Paulo Ernando Ferraz Cavalcanti Michel Pompeu Barros de Oliveira Sá Cecília Andrade dos Santos Isaac Melo Esmeraldo Mariana Leal Chaves Ricardo Felipe de Albuquerque Lins Ricardo de Carvalho Lima 《Brazilian Journal Of Cardiovascular Surgery》2015,30(2):148-158