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1.
J Biol Chem ; 296: 100070, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33187980

RESUMO

Lipids in complex, protein-enriched films at air/liquid interfaces reduce surface tension. In the absence of this benefit, the light refracting and immunoprotective tear film on eyes would collapse. Premature collapse, coupled with chronic inflammation compromising visual acuity, is a hallmark of dry eye disease affecting 7 to 10% of individuals worldwide. Although collapse seems independent of mutation (unlike newborn lung alveoli), selective proteome and possible lipidome changes have been noted. These include elevated tissue transglutaminase and consequent inactivation through C-terminal cross-linking of the tear mitogen lacritin, leading to significant loss of lacritin monomer. Lacritin monomer restores homeostasis via autophagy and mitochondrial fusion and promotes basal tearing. Here, we discover that lacritin monomer C-terminal processing, inclusive of cysteine, serine, and metalloproteinase activity, generates cationic amphipathic α-helical proteoforms. Such proteoforms (using synthetic peptide surrogates) act like alveolar surfactant proteins to rapidly bind and stabilize the tear lipid layer. Immunodepletion of C- but not N-terminal proteoforms nor intact lacritin, from normal human tears promotes loss of stability akin to human dry eye tears. Stability of these and dry eye tears is rescuable with C- but not N-terminal proteoforms. Repeated topical application in rabbits reveals a proteoform turnover time of 7 to 33 h with gradual loss from human tear lipid that retains bioactivity without further processing. Thus, the processed C-terminus of lacritin that is deficient or absent in dry eye tears appears to play a key role in preventing tear film collapse and as a natural slow release mechanism that restores epithelial homeostasis.


Assuntos
Síndromes do Olho Seco/fisiopatologia , Proteínas do Olho/metabolismo , Glicoproteínas/fisiologia , Isoformas de Proteínas/fisiologia , Lágrimas/metabolismo , Animais , Modelos Animais de Doenças , Humanos , Glândulas Tarsais/fisiologia , Coelhos
2.
Biosci Trends ; 14(1): 48-55, 2020 Mar 16.
Artigo em Inglês | MEDLINE | ID: mdl-32023563

RESUMO

The aim of this multicentric retrospective study is to evaluate the predictive and prognostic performance of neutrophil to lymphocyte ratio (NLR), platelet-lymphocyte ratio (PLR) and their dynamics in patients with non-small cell lung cancer (NSCLC) treated with pembrolizumab as a second line. Patients with metastatic NSCLC (n = 119), whose tumors expressed programmed death-ligand 1 (PD-L1) ≥ 1%, were retrospectively analyzed between Apr 2017 and Apr 2019. All patients received platinum-containing chemotherapy as a first line treatment. Pre-treatment NLR was calculated by dividing the number of neutrophils by the number of lymphocytes in peripheral blood before the first pembrolizumab infusion. Progression free survival (PFS) and overall survival (OS) was compared by Kaplan-Meier method and Cox Proportional Hazard model. Patients with NLR > 5 before immunotherapy showed significantly shorter mean PFS of 6.86 months (95% CI: 5.81-7.90) as compared to those with NLR ≤ 5 of 18.82 months (95% CI: 15.87-21.78) (long rank test p < 0.001). Furthermore in the multivariate analysis, only NLR > 5 was an independent predictive factor for shorter PFS (HR: 4.47, 95% CI: 2.20-9.07, p < 0.001). In multivariate analysis, presence of bone metastases (HR: 2.08, 95% CI: 1.10-4.94, p = 0.030), NLR > 5 before chemotherapy (HR: 8.09, 95% CI: 2.35-27.81, p = 0.001) and high PLR before chemotherapy (HR: 2.81, 95% CI: 1.13-6.97, p = 0.025) were found to be independent negative prognostic factors for poor OS. Our data suggests that NLR ≤ 5 is a potential predictive marker, which may identify patients appropriate for immunotherapy as a second line treatment.


Assuntos
Anticorpos Monoclonais Humanizados/uso terapêutico , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Neoplasias Pulmonares/tratamento farmacológico , Linfócitos/citologia , Neutrófilos/citologia , Idoso , Antígeno B7-H1 , Biomarcadores , Carcinoma Pulmonar de Células não Pequenas/diagnóstico , Feminino , Humanos , Imunoterapia , Estimativa de Kaplan-Meier , Neoplasias Pulmonares/diagnóstico , Masculino , Pessoa de Meia-Idade , Compostos de Platina/uso terapêutico , Modelos de Riscos Proporcionais , Estudos Retrospectivos , Taxa de Sobrevida
3.
Chemosphere ; 168: 508-513, 2017 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-27871034

RESUMO

Isotope fractionation between benzene-D0 and benzene-D6 caused by multi-step partitioning of the benzenes between water and two organic solvents, n-octane and 1-octanol, as well as between water and the gas phase, was measured. The obtained fractionation factors αH = KH/KD are αH = 1.080 ± 0.015 and αH = 1.074 ± 0.015 for extraction into n-octane and 1-octanol, respectively, and αH = 1.049 ± 0.010 for evaporation from aqueous solution. The comparison of solvent- and gas-phase partitioning reveals that about 2/3 of the driving force of fractionation is due to different interactions in the aqueous phase, whereas 1/3 is due to different interactions in the organic phase. The heavy benzene isotopologue behaves more 'hydrophilically' and the light one more 'hydrophobically'. This synergistic alignment gives rise to relatively large fractionation effects in partitioning between water and non-polar organic matter. In contrast to a previous study, there is no indication of strong fractionation by specific interactions between benzene and octanol. Partitioning under non-equilibrium conditions yields smaller apparent fractionation effects due to opposite trends of thermodynamic and kinetic fractionation parameters, i.e. partition and diffusion coefficients of the isotopologues. This may have consequences which should be taken into account when considering isotope fractionation due to sorption in environmental compartments.


Assuntos
Benzeno/química , Deutério/química , Poluentes Químicos da Água/química , Fracionamento Químico , Ligação de Hidrogênio , Interações Hidrofóbicas e Hidrofílicas
4.
J Contam Hydrol ; 181: 59-68, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-25864966

RESUMO

The application of nanoscale zero-valent iron (nZVI) for subsurface remediation of groundwater contaminants is a promising new technology, which can be understood as alternative to the permeable reactive barrier technique using granular iron. Dechlorination of organic contaminants by zero-valent iron seems promising. Currently, one limitation to widespread deployment is the fast agglomeration and sedimentation of nZVI in colloidal suspensions, even more so when in soils and sediments, which limits the applicability for the treatment of sources and plumes of contamination. Colloid-supported nZVI shows promising characteristics to overcome these limitations. Mobility of Carbo-Iron Colloids (CIC) - a newly developed composite material based on finely ground activated carbon as a carrier for nZVI - was tested in a field application: In this study, a horizontal dipole flow field was established between two wells separated by 5.3m in a confined, natural aquifer. The injection/extraction rate was 500L/h. Approximately 1.2kg of CIC was suspended with the polyanionic stabilizer carboxymethyl cellulose. The suspension was introduced into the aquifer at the injection well. Breakthrough of CIC was observed visually and based on total particle and iron concentrations detected in samples from the extraction well. Filtration of water samples revealed a particle breakthrough of about 12% of the amount introduced. This demonstrates high mobility of CIC particles and we suggest that nZVI carried on CIC can be used for contaminant plume remediation by in-situ formation of reactive barriers.


Assuntos
Carvão Vegetal/química , Recuperação e Remediação Ambiental/métodos , Ferro/química , Nanopartículas Metálicas/química , Carbono/química , Carboximetilcelulose Sódica/química , Coloides/análise , Coloides/química , Alemanha , Água Subterrânea/análise , Água Subterrânea/química , Halogenação , Ferro/análise , Nanopartículas Metálicas/análise , Solo , Suspensões/química , Poluição da Água
5.
Cell Physiol Biochem ; 33(1): 117-28, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24481011

RESUMO

BACKGROUND/AIMS: ageing is associated with a marked decline in immune function which may contribute to the local environment that can influence the regenerative process of skeletal muscle cells. METHODS: Herein, we focused on determining the effect of an activated immune system secretome on myoblast differentiation and proliferation as possible means to attenuate adverse effects of muscle aging. C2C12 myoblasts were used as model to assess the impact of lymphocyte conditioned media (CM) following anti-CD3/IL-2 activation. RESULTS: Myoblasts cultured with activated lymphocytes CM exhibited reduced morphological and biochemical differentiation (98±20, p<0.005) and increased entry to the S Phase of the cell cycle (61%±7, p<0.001), when compared with myoblasts cultured with non-activated lymphocytes CM. Associated with increased proliferation and reduced differentiation, muscle specific transcription factors MyoD and myogenin were significantly reduced in C2C12 treated with activated lymphocytes CM vs control CM, respectively (myoD: 0.5±0.12 fold reduction P<0.005); myogenin: 0.38±0.08 fold reduction; p<0.005). Moreover, key protein of proliferation pERK1/2 increased (46±11U/ml, p<0.05) whereas mediator of differentiation pAkt decreased (21±12U/ml, p<0.05) in C2C12 treated with activated vs. non-activated CM. CONCLUSION: our data demonstrate that, following activation, secretome of the immune system cells elicit marked regulatory effects on skeletal muscle growth and differentiation; enhancing the former with the loss of the latter.


Assuntos
Diferenciação Celular , Ativação Linfocitária , Linfócitos/metabolismo , Mioblastos/citologia , Adulto , Animais , Ciclo Celular , Linhagem Celular , Proliferação de Células , Forma Celular , MAP Quinases Reguladas por Sinal Extracelular/metabolismo , Feminino , Humanos , Processamento de Imagem Assistida por Computador , Masculino , Camundongos , Proteína MyoD/genética , Proteína MyoD/metabolismo , Mioblastos/metabolismo , Miogenina/genética , Miogenina/metabolismo , Fosforilação , Proteínas Proto-Oncogênicas c-akt/metabolismo , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Transdução de Sinais , Adulto Jovem
6.
Breast Cancer ; 21(5): 590-7, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-23104395

RESUMO

PURPOSE: To evaluate the detection of epithelial cells in bone marrow of breast cancer patients as an indicator of metastatic disease. PATIENTS AND METHODS: Between 2001 and 2005, bone marrow biopsies were taken from 79 breast cancer patients during primary surgery. Specimens were stained immunocytochemically for epithelial cells expressing cytokeratins or epithelial membrane antigen. The long-term outcomes of these patients were analyzed. RESULTS: In 51 CK-positive results of 79 patients, epithelial cells were found in the bone marrow (BM) biopsies. These patients were designated CK(+). The rate of tumor recurrence or cancer-related death was significantly higher in CK(+) patients than in CK-negative patients. Multivariate analysis using the Cox regression model revealed BM status as a prognostic parameter independent of axillary lymph node status. CONCLUSION: Disseminated epithelial cells in BM are associated with poor clinical outcome in breast cancer patients. However, the presence of these cells is not a sufficient parameter, suggesting that epithelial cells in the BM of breast cancer patients at the time of surgery have limited metastatic potential. The role of these cells needs to be further evaluated.


Assuntos
Biomarcadores Tumorais/metabolismo , Células da Medula Óssea/metabolismo , Neoplasias da Mama/patologia , Neoplasias da Mama/cirurgia , Células Epiteliais/metabolismo , Queratina-19/metabolismo , Micrometástase de Neoplasia/patologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Neoplasias da Mama/metabolismo , Neoplasias da Mama/mortalidade , Intervalo Livre de Doença , Células Epiteliais/patologia , Feminino , Seguimentos , Humanos , Pessoa de Meia-Idade , Análise Multivariada , Estudos Prospectivos , Resultado do Tratamento
7.
J Muscle Res Cell Motil ; 34(2): 125-36, 2013 May.
Artigo em Inglês | MEDLINE | ID: mdl-23553034

RESUMO

Muscle progenitor cell migration is an important step in skeletal muscle myogenesis and regeneration. Migration is required for muscle precursors to reach the site of damage and for the alignment of myoblasts prior to their fusion, which ultimately contributes to muscle regeneration. Limited spreading and migration of donor myoblasts are reported problems of myoblast transfer therapy, a proposed therapeutic strategy for Duchenne Muscular Dystrophy, warranting further investigation into different approaches for improving the motility and homing of these cells. In this article, the effect of protein phospho-tyrosine phosphatase and PTEN inhibitor BpV(Hopic) on C2C12 myoblast migration and differentiation was investigated. Applying a wound healing migration model, it is reported that 1 µM BpV(Hopic) is capable of enhancing the migration of C2C12 myoblasts by approximately 40 % in the presence of myotube conditioned media, without significantly affecting their capacity to differentiate and fuse into multinucleated myotubes. Improved migration of myoblasts treated with 1 µM BpV(Hopic) was associated with activation of PI3K/AKT and MAPK/ERK pathways, while their inhibition with either LY294002 or UO126, respectively, resulted in a reduction of C2C12 migration back to control levels. These results propose that bisperoxovanadium compounds may be considered as potential tools for enhancing the migration of myoblasts, while not reducing their differentiation capacity and underpin the importance of PI3K/AKT and MAPK/ERK signalling for the process of myogenic progenitor migration.


Assuntos
Movimento Celular/efeitos dos fármacos , Inibidores Enzimáticos/farmacologia , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Mioblastos/enzimologia , PTEN Fosfo-Hidrolase/antagonistas & inibidores , Fosfatidilinositol 3-Quinases/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Animais , Linhagem Celular , Inibidores Enzimáticos/química , Camundongos , Mioblastos/citologia , PTEN Fosfo-Hidrolase/metabolismo , Inibidores de Fosfoinositídeo-3 Quinase , Proteínas Proto-Oncogênicas c-akt/antagonistas & inibidores
8.
World J Pediatr Congenit Heart Surg ; 3(3): 321-7, 2012 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-23804864

RESUMO

BACKGROUND: The study evaluates the long-term results of surgery for anomalous left coronary artery from the pulmonary artery (ALCAPA) with special attention on the left ventricular (LV) function and mitral regurgitation. METHODS: Twenty-one children underwent surgery for ALCAPA over 23 years (1987-2010). All patients underwent establishment of a two-coronary system, by direct reimplantation (n = 13) or by intrapulmonary tunnel technique (n = 8), with concomitant mitral valve repair in one. The follow-up echocardiograms were evaluated to assess LV function and mitral regurgitation. RESULTS: Five patients died. The age of the nonsurvivors was lower, 4.2 ± 1.3 versus 22.7 ± 29.4 months, P = .04. All nonsurvivors had moderate or severe mitral regurgitation preoperatively and higher LV diameter z score than the survivors: 11.8 (9-14.6) versus 4.6 (1.9-13.1), P = .01. At last follow-up, all survivors were asymptomatic; the diastolic LV diameter was normal, with z scores: 0.3 (0.1-1.9) versus 7 (1.9-14.6) preoperatively, P = .001, as was the LV ejection fraction: 66% (61%-78%) versus 38% (16%-70%) preoperatively, P = .001. Fifteen patients had moderate or severe mitral regurgitation at initial presentation and it eventually regressed to insignificant in all survivors (P = .001). No subsequent interventions on the coronary arteries or the mitral valve were needed. Four patients with intrapulmonary tunnel had mild suprapulmonary obstruction with Doppler peak gradients between 20 and 30 mm Hg. CONCLUSIONS: In our experience, establishment of a two-coronary circulation without mitral valve repair leads to normalization of LV dimension and systolic function and to improvement of mitral regurgitation in the surviving patients. Mortality is related to low age and to the associated higher degree of LV dysfunction.

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