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1.
Int J Geriatr Psychiatry ; 32(12): e150-e156, 2017 12.
Artigo em Inglês | MEDLINE | ID: mdl-28185311

RESUMO

OBJECTIVE: Despite high rates of mortality and depression, there is limited knowledge of how depressive symptoms, especially feeling of hopefulness, affect mortality in the homebound elderly. METHODS: We conducted a secondary analysis of data from a community sample of 1034 adults, age 60 years and older. The Center for Epidemiologic Studies Depression Scale was used to evaluate the mood symptoms and feeling of hopefulness at baseline. The death data were collected within an 8-year follow-up period. Analysis of variance and Chi-square were used to compare the clinical conditions among the groups of individuals who feel hopeful always, sometimes, and rarely. Logistic regression was used to explore the association between the hopefulness about the future and mortality as an outcome. RESULTS: In the 8-year follow-up period, frequency of feeling hopeful, but not other individual depressive symptoms, was associated with mortality rate. The mortality rate among those who always, sometimes, and rarely felt hopeful were 21.6%, 26.4%, and 35.7%, respectively (P = 0.002). Logistic regression also confirmed that individuals who rarely feel hopeful had higher odds of decease within the 8-year follow-up period than those who always felt hopeful (OR = 1.74, CI = 1.14-2.65) after adjusting for age and medical conditions. CONCLUSIONS: Baseline hopefulness predicts mortality outcome among the homebound elderly in the community. Identifying individuals who are depressed with hopelessness in the elderly and providing early intervention may improve the mortality rate. Copyright © 2017 John Wiley & Sons, Ltd.


Assuntos
Transtorno Depressivo/mortalidade , Pacientes Domiciliares/psicologia , Esperança , Mortalidade , Idoso , Idoso de 80 Anos ou mais , Análise de Variância , Feminino , Humanos , Modelos Logísticos , Masculino , Pessoa de Meia-Idade
2.
Cancer Immunol Res ; 4(3): 194-203, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26787823

RESUMO

Tumor responses to programmed cell death protein 1 (PD-1) blockade therapy are mediated by T cells, which we characterized in 102 tumor biopsies obtained from 53 patients treated with pembrolizumab, an antibody to PD-1. Biopsies were dissociated, and single-cell infiltrates were analyzed by multicolor flow cytometry using two computational approaches to resolve the leukocyte phenotypes at the single-cell level. There was a statistically significant increase in the frequency of T cells in patients who responded to therapy. The frequency of intratumoral B cells and monocytic myeloid-derived suppressor cells significantly increased in patients' biopsies taken on treatment. The percentage of cells with a regulatory T-cell phenotype, monocytes, and natural killer cells did not change while on PD-1 blockade therapy. CD8(+) memory T cells were the most prominent phenotype that expanded intratumorally on therapy. However, the frequency of CD4(+) effector memory T cells significantly decreased on treatment, whereas CD4(+) effector T cells significantly increased in nonresponding tumors on therapy. In peripheral blood, an unusual population of blood cells expressing CD56 was detected in two patients with regressing melanoma. In conclusion, PD-1 blockade increases the frequency of T cells, B cells, and myeloid-derived suppressor cells in tumors, with the CD8(+) effector memory T-cell subset being the major T-cell phenotype expanded in patients with a response to therapy.


Assuntos
Anticorpos Monoclonais Humanizados/uso terapêutico , Antineoplásicos/uso terapêutico , Melanoma/tratamento farmacológico , Neoplasias Cutâneas/tratamento farmacológico , Subpopulações de Linfócitos T/imunologia , Idoso , Anticorpos Monoclonais Humanizados/farmacologia , Antineoplásicos/farmacologia , Feminino , Humanos , Masculino , Melanoma/imunologia , Melanoma/secundário , Pessoa de Meia-Idade , Receptor de Morte Celular Programada 1/antagonistas & inibidores , Neoplasias Cutâneas/imunologia , Neoplasias Cutâneas/patologia , Resultado do Tratamento
3.
Nature ; 515(7528): 568-71, 2014 Nov 27.
Artigo em Inglês | MEDLINE | ID: mdl-25428505

RESUMO

Therapies that target the programmed death-1 (PD-1) receptor have shown unprecedented rates of durable clinical responses in patients with various cancer types. One mechanism by which cancer tissues limit the host immune response is via upregulation of PD-1 ligand (PD-L1) and its ligation to PD-1 on antigen-specific CD8(+) T cells (termed adaptive immune resistance). Here we show that pre-existing CD8(+) T cells distinctly located at the invasive tumour margin are associated with expression of the PD-1/PD-L1 immune inhibitory axis and may predict response to therapy. We analysed samples from 46 patients with metastatic melanoma obtained before and during anti-PD-1 therapy (pembrolizumab) using quantitative immunohistochemistry, quantitative multiplex immunofluorescence, and next-generation sequencing for T-cell antigen receptors (TCRs). In serially sampled tumours, patients responding to treatment showed proliferation of intratumoral CD8(+) T cells that directly correlated with radiographic reduction in tumour size. Pre-treatment samples obtained from responding patients showed higher numbers of CD8-, PD-1- and PD-L1-expressing cells at the invasive tumour margin and inside tumours, with close proximity between PD-1 and PD-L1, and a more clonal TCR repertoire. Using multivariate analysis, we established a predictive model based on CD8 expression at the invasive margin and validated the model in an independent cohort of 15 patients. Our findings indicate that tumour regression after therapeutic PD-1 blockade requires pre-existing CD8(+) T cells that are negatively regulated by PD-1/PD-L1-mediated adaptive immune resistance.


Assuntos
Imunidade Adaptativa/imunologia , Linfócitos T CD8-Positivos/imunologia , Imunoterapia , Melanoma/terapia , Modelos Biológicos , Idoso , Idoso de 80 Anos ou mais , Biomarcadores , Linfócitos T CD8-Positivos/citologia , Proliferação de Células , Feminino , Regulação Neoplásica da Expressão Gênica , Humanos , Masculino , Melanoma/diagnóstico , Melanoma/imunologia , Melanoma/patologia , Pessoa de Meia-Idade , Análise Multivariada , Receptor de Morte Celular Programada 1/antagonistas & inibidores , Receptor de Morte Celular Programada 1/genética , Receptor de Morte Celular Programada 1/imunologia , Resultado do Tratamento
4.
PLoS One ; 5(8): e12009, 2010 Aug 06.
Artigo em Inglês | MEDLINE | ID: mdl-20700454

RESUMO

Genetically modified mice carrying engrafted human tissues provide useful models to study human cell biology in physiologically relevant contexts. However, there remain several obstacles limiting the compatibility of human cells within their mouse hosts. Among these is inadequate cross-reactvitiy between certain mouse cytokines and human cellular receptors, depriving the graft of important survival and growth signals. To circumvent this problem, we utilized a lentivirus-based delivery system to express physiologically relevant levels of human interleukin-7 (hIL-7) in Rag2-/-gammac-/- mice following a single intravenous injection. hIL-7 promoted homeostatic proliferation of both adoptively transferred and endogenously generated T-cells in Rag2-/-gammac-/- Human Immune System (HIS) mice. Interestingly, we found that hIL-7 increased T lymphocyte numbers in the spleens of HIV infected HIS mice without affecting viral load. Taken together, our study unveils a versatile approach to deliver human cytokines to HIS mice, to both improve engraftment and determine the impact of cytokines on human diseases.


Assuntos
Técnicas de Transferência de Genes , Vetores Genéticos/genética , Interleucina-7/genética , Interleucina-7/imunologia , Lentivirus/genética , Linfócitos T/citologia , Linfócitos T/metabolismo , Animais , Contagem de Células , Proliferação de Células , Regulação da Expressão Gênica , Infecções por HIV/imunologia , Homeostase , Humanos , Camundongos , Proteínas Proto-Oncogênicas/metabolismo , Proteínas Proto-Oncogênicas c-bcl-2 , Baço/citologia , Linfócitos T/imunologia , Carga Viral
5.
BMC Mol Biol ; 8: 98, 2007 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-17971228

RESUMO

BACKGROUND: Effective and stable knockdown of multiple gene targets by RNA interference is often necessary to overcome isoform redundancy, but it remains a technical challenge when working with intractable cell systems. RESULTS: We have developed a flexible platform using RNA polymerase II promoter-driven expression of microRNA-like short hairpin RNAs which permits robust depletion of multiple target genes from a single transcript. Recombination-based subcloning permits expression of multi-shRNA transcripts from a comprehensive range of plasmid or viral vectors. Retroviral delivery of transcripts targeting isoforms of cAMP-dependent protein kinase in the RAW264.7 murine macrophage cell line emphasizes the utility of this approach and provides insight to cAMP-dependent transcription. CONCLUSION: We demonstrate functional consequences of depleting multiple endogenous target genes using miR-shRNAs, and highlight the versatility of the described vector platform for multiple target gene knockdown in mammalian cells.


Assuntos
Inativação Gênica , MicroRNAs , Interferência de RNA , RNA Interferente Pequeno/metabolismo , Animais , Moléculas de Adesão Celular/metabolismo , Linhagem Celular , AMP Cíclico/metabolismo , AMP Cíclico/farmacologia , Proteínas Quinases Dependentes de AMP Cíclico/metabolismo , Vetores Genéticos , Humanos , Isoenzimas/metabolismo , Rim/citologia , Lentivirus/genética , Macrófagos/metabolismo , Camundongos , Proteínas dos Microfilamentos/metabolismo , Fosfoproteínas/metabolismo , Fosforilação , Plasmídeos , Regiões Promotoras Genéticas , RNA Polimerase II/metabolismo , RNA Mensageiro/metabolismo , Recombinação Genética , Retroviridae/genética , Transcrição Gênica , Transfecção
6.
J Struct Biol ; 160(1): 103-13, 2007 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-17723309

RESUMO

We have developed methods to locate individual ligands that can be used for electron microscopy studies of dynamic events during endocytosis and subsequent intracellular trafficking. The methods are based on enlargement of 1.4 nm Nanogold attached to an endocytosed ligand. Nanogold, a small label that does not induce misdirection of ligand-receptor complexes, is ideal for labeling ligands endocytosed by live cells, but is too small to be routinely located in cells by electron microscopy. Traditional pre-embedding enhancement protocols to enlarge Nanogold are not compatible with high pressure freezing/freeze substitution fixation (HPF/FSF), the most accurate method to preserve ultrastructure and dynamic events during trafficking. We have developed an improved enhancement procedure for chemically fixed samples that reduced auto-nucleation, and a new pre-embedding gold enlarging technique for HPF/FSF samples that preserved contrast and ultrastructure and can be used for high-resolution tomography. We evaluated our methods using labeled Fc as a ligand for the neonatal Fc receptor. Attachment of Nanogold to Fc did not interfere with receptor binding or uptake, and gold-labeled Fc could be specifically enlarged to allow identification in 2D projections and in tomograms. These methods should be broadly applicable to many endocytosis and transcytosis studies.


Assuntos
Endocitose , Congelamento , Ouro/química , Nanopartículas Metálicas , Microscopia Eletrônica/métodos , Animais , Animais Recém-Nascidos , Concentração de Íons de Hidrogênio , Ratos , Ratos Sprague-Dawley
7.
Mol Cell Proteomics ; 6(3): 413-24, 2007 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-17192258

RESUMO

Cellular responses to inputs that vary both temporally and spatially are determined by complex relationships between the components of cell signaling networks. Analysis of these relationships requires access to a wide range of experimental reagents and techniques, including the ability to express the protein components of the model cells in a variety of contexts. As part of the Alliance for Cellular Signaling, we developed a robust method for cloning large numbers of signaling ORFs into Gateway entry vectors, and we created a wide range of compatible expression platforms for proteomics applications. To date, we have generated over 3000 plasmids that are available to the scientific community via the American Type Culture Collection. We have established a website at www.signaling-gateway.org/data/plasmid/ that allows users to browse, search, and blast Alliance for Cellular Signaling plasmids. The collection primarily contains murine signaling ORFs with an emphasis on kinases and G protein signaling genes. Here we describe the cloning, databasing, and application of this proteomics resource for large scale subcellular localization screens in mammalian cell lines.


Assuntos
Proteínas Quinases/metabolismo , Proteômica , Animais , Linhagem Celular , Clonagem Molecular , DNA Complementar/genética , Bases de Dados Factuais , Camundongos , Fases de Leitura Aberta/genética , Plasmídeos , Proteínas Quinases/genética , Transdução de Sinais
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