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1.
Braz J Med Biol Res ; 54(4): e10766, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33624732

RESUMO

The novel Coronavirus disease (COVID-19) is responsible for thousands of deaths worldwide, especially in Brazil, currently one of the leading countries in number of infections and deaths. The beginning of the COVID-19 epidemic in Brazil is uncertain due to the low number of tests done in the country. The excess number of deaths can suggest the beginning of the pandemic in this context. In this article, we used an autoregressive integrated moving average (ARIMA) model to investigate possible excesses in the number of deaths processed by the São Paulo Autopsy Service according to different causes of deaths: all-cause, cardiovascular, and pulmonary causes. We calculated the expected number of deaths using data from 2019 to 2020 (n=17,011), and investigated different seasonal patterns using harmonic dynamic regression with Fourier terms with residuals modeled by an ARIMA method. We did not find any abnormalities in the predicted number of deaths and the real values in the first months of 2020. We found an increase in the number of deaths only by March 20, 2020, right after the first COVID-19 confirmed case in the city of São Paulo, which occurred on March 16, 2020.


Assuntos
COVID-19 , Coronavirus , Autopsia , Brasil/epidemiologia , Humanos , Pandemias , SARS-CoV-2
2.
Braz. j. med. biol. res ; 54(4): e10766, 2021. tab, graf
Artigo em Inglês | LILACS | ID: biblio-1153540

RESUMO

The novel Coronavirus disease (COVID-19) is responsible for thousands of deaths worldwide, especially in Brazil, currently one of the leading countries in number of infections and deaths. The beginning of the COVID-19 epidemic in Brazil is uncertain due to the low number of tests done in the country. The excess number of deaths can suggest the beginning of the pandemic in this context. In this article, we used an autoregressive integrated moving average (ARIMA) model to investigate possible excesses in the number of deaths processed by the São Paulo Autopsy Service according to different causes of deaths: all-cause, cardiovascular, and pulmonary causes. We calculated the expected number of deaths using data from 2019 to 2020 (n=17,011), and investigated different seasonal patterns using harmonic dynamic regression with Fourier terms with residuals modeled by an ARIMA method. We did not find any abnormalities in the predicted number of deaths and the real values in the first months of 2020. We found an increase in the number of deaths only by March 20, 2020, right after the first COVID-19 confirmed case in the city of São Paulo, which occurred on March 16, 2020.


Assuntos
Humanos , Coronavirus , COVID-19 , Autopsia , Brasil/epidemiologia , Pandemias , SARS-CoV-2
3.
Cancer Gene Ther ; 21(8): 317-32, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-24971583

RESUMO

Optimal tumor cell surface expression of human leukocyte antigen (HLA) class I molecules is essential for the presentation of tumor-associated peptides to T-lymphocytes. However, a hallmark of many types of tumor is the loss or downregulation of HLA class I expression associated with ineffective tumor antigen presentation to T cells. Frequently, HLA loss can be caused by structural alterations in genes coding for HLA class I complex, including the light chain of the complex, ß2-microglobulin (ß2m). Its best-characterized function is to interact with HLA heavy chain and stabilize the complex leading to a formation of antigen-binding cleft recognized by T-cell receptor on CD8+ T cells. Our previous study demonstrated that alterations in the ß2m gene are frequently associated with cancer immune escape leading to metastatic progression and resistance to immunotherapy. These types of defects require genetic transfer strategies to recover normal expression of HLA genes. Here we characterize a replication-deficient adenoviral vector carrying human ß2m gene, which is efficient in recovering proper tumor cell surface HLA class I expression in ß2m-negative tumor cells without compromising the antigen presentation machinery. Tumor cells transduced with ß2m induced strong activation of T cells in a peptide-specific HLA-restricted manner. Gene therapy using recombinant adenoviral vectors encoding HLA genes increases tumor antigen presentation and represents a powerful tool for modulation of tumor cell immunogenicity by restoration of missing or altered HLA genes. It should be considered as part of cancer treatment in combination with immunotherapy.


Assuntos
Adenoviridae/genética , Expressão Gênica , Vetores Genéticos/genética , Antígenos de Histocompatibilidade Classe I/genética , Neoplasias/genética , Neoplasias/imunologia , Subpopulações de Linfócitos T/imunologia , Microglobulina beta-2/genética , Apresentação de Antígeno/imunologia , Apoptose/genética , Linhagem Celular Tumoral , Proliferação de Células , Loci Gênicos , Antígenos de Histocompatibilidade Classe I/metabolismo , Humanos , Imuno-Histoquímica , Imunofenotipagem , Melanoma/genética , Melanoma/metabolismo , Subpopulações de Linfócitos T/metabolismo , Transcrição Gênica , Transdução Genética , Transgenes , Microglobulina beta-2/metabolismo
4.
Tissue Antigens ; 79(3): 147-54, 2012 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-22309256

RESUMO

The dynamic interaction between the host immune system and growing cancer has been of central interest to the field of tumor immunology over the past years. Recognition of tumor-associated antigens (TAA) by self-HLA (human leukocyte antigen) class I-restricted CD8+ T cells is a main feature in the detection and destruction of malignant cells. The discovery and molecular characterization of TAA has changed the field of cancer treatment and introduced a new era of cancer immunotherapy aimed at increasing tumor immunogenicity and T-cell-mediated anti-tumor immunity. Unfortunately, while these new protocols of cancer immunotherapy are mediating induction of tumor-specific T lymphocytes in patients with certain malignancies, they have not yet delivered substantial clinical benefits, such as induction of tumor regression or increased disease-free survival. It has become apparent that lack of tumor rejection is the result of immune selection and escape by tumor cells that develop low immunogenic phenotypes. Substantial experimental data support the existence of a variety of different mechanisms involved in the tumor escape phase, including loss or downregulation of HLA class I antigens. These alterations could be caused by regulatory ('soft') or by structural/irreversible ('hard') defects. On the basis of the evidence obtained from experimental mouse cancer models and metastatic human tumors, the structural defects underlying HLA class I loss may have profound implications on T-cell-mediated tumor rejection and ultimately on the outcome of cancer immunotherapy. Strategies to overcome this obstacle, including gene therapy to recover normal expression of HLA class I genes, require consideration. In this review, we outline the importance of monitoring and correction of HLA class I alterations during cancer development and immunotherapy.


Assuntos
Regulação Neoplásica da Expressão Gênica , Antígenos de Histocompatibilidade Classe I/metabolismo , Imunoterapia , Animais , Modelos Animais de Doenças , Antígenos de Histocompatibilidade Classe I/genética , Humanos , Neoplasias/terapia
5.
Scand J Immunol ; 70(2): 125-35, 2009 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-19630918

RESUMO

Here we report a successful use of a non-replicating adenovirus expressing the wild-type human beta2m gene in recovery of normal human leucocyte antigen (HLA) class I expression in beta2m-null cancer cells. Total loss of HLA class I expression in these cell lines is caused by a mutation in beta2m gene and a loss of heterozygosity in chromosome 15 carrying another copy of that gene. Normal HLA class I expression on the tumour cell surface is critical for the successful outcome of cancer immunotherapy as T cells can only recognize tumour-derived peptides in a complex with self-HLA class I molecules. In this report we characterize the newly generated adenoviral vector AdCMVbeta2m and demonstrate an efficient beta2m gene transfer in tumour cell lines of different histological origin, including melanoma, prostate and colorectal carcinoma. The beta2m re-expression lasted for an extended period of time both in vitro and in vivo in human tumour xenograft transplants. We propose that in a subset of cancer patients with structural defect in beta2m gene or chromosome 15, the adenoviral-mediated recovery (or even increase) of HLA class I expression on tumour cells in combination with vaccination or adoptive T-cell therapy can provide a complementary approach to improve the clinical efficacy of cancer immunotherapy.


Assuntos
Terapia Genética , Antígenos de Histocompatibilidade Classe I/imunologia , Imunoterapia , Neoplasias/terapia , Microglobulina beta-2/genética , Animais , Linhagem Celular , Linhagem Celular Tumoral , Expressão Gênica , Técnicas de Transferência de Genes , Vetores Genéticos , Humanos , Camundongos , Camundongos Nus , Neoplasias/imunologia , Ensaios Antitumorais Modelo de Xenoenxerto
7.
J Neurosci Res ; 75(2): 182-193, 2004 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-14705139

RESUMO

We demonstrate the presence and functional properties of Group I metabotropic glutamate receptors (mGluRs) expressed in chromaffin cells. Immunocytochemical techniques revealed that two mGluR subtypes (mGluR1alpha and mGluR5) are expressed in chromaffin cells, located in both the cytoplasmic membrane and the cytosol surrounding the nucleus. These mGluRs are functionally active on catecholamine (CA) secretion in chromaffin cells because both (1S, 3R)-1-aminocyclopentane-1,3-dicarboxylic acid (t-ACPD) and the specific agonist of Group I mGluRs, (S)-3,5-dihydroxyphenylglycine (DHPG), were able to stimulate the release of CAs (adrenaline and noradrenaline) in a dose-response manner. These effects were specifically reversed by L-(+)-2-amino-3-phosphonopropionic acid (L-AP3), a selective antagonist of the Group I metabotropic glutamate receptors. t-ACPD induced an increase in CA secretion in both the presence and absence of extracellular calcium, the former effect being accompanied by cell membrane depolarization. Noradrenaline (NA) release was higher in the presence of extracellular calcium than in its absence, whereas adrenaline release was of the same order under both conditions. These results indicate that different subtypes of Group I mGluRs are present in noradrenergic and adrenergic cells. Fluorescence imaging techniques in single cells showed different t-ACPD-induced increases in intracellular calcium in different chromaffin cells: in chromaffin cells, 67% expressed functional metabotropic glutamate receptors and with nicotinic receptors, whereas the remaining 33% expressed only nicotinic receptors. In the absence of external calcium, only about 25% of cells responded to t-ACPD-increased intracellular calcium by increasing inositol 1,4,5-trisphosphate (IP(3)) concentration and subsequent calcium mobilization from intracellular stores, whereas the remaining 75% increased intracellular calcium by promoting Ca(2+) influx from the extracellular medium through L- and N- but not P/Q voltage-dependent calcium channels.


Assuntos
Medula Suprarrenal/metabolismo , Alanina/análogos & derivados , Células Cromafins/metabolismo , Metoxi-Hidroxifenilglicol/análogos & derivados , Receptores de Glutamato Metabotrópico/metabolismo , Medula Suprarrenal/citologia , Alanina/farmacologia , Animais , Cálcio/metabolismo , Cálcio/farmacologia , Canais de Cálcio/efeitos dos fármacos , Canais de Cálcio/metabolismo , Sinalização do Cálcio/efeitos dos fármacos , Sinalização do Cálcio/fisiologia , Bovinos , Células Cultivadas , Células Cromafins/citologia , Células Cromafins/efeitos dos fármacos , Cicloleucina/análogos & derivados , Cicloleucina/farmacologia , Agonistas de Aminoácidos Excitatórios/farmacologia , Antagonistas de Aminoácidos Excitatórios/farmacologia , Líquido Extracelular/efeitos dos fármacos , Líquido Extracelular/metabolismo , Inositol 1,4,5-Trifosfato/metabolismo , Potenciais da Membrana/efeitos dos fármacos , Potenciais da Membrana/fisiologia , Metoxi-Hidroxifenilglicol/farmacologia , Nicotina/farmacologia , Norepinefrina/metabolismo , Tempo de Reação/efeitos dos fármacos , Tempo de Reação/fisiologia , Receptor de Glutamato Metabotrópico 5 , Receptores de Glutamato Metabotrópico/efeitos dos fármacos , Receptores Nicotínicos/efeitos dos fármacos , Receptores Nicotínicos/metabolismo
8.
Eur J Clin Microbiol Infect Dis ; 23(2): 116-8, 2004 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-14712368

RESUMO

Reported here is a rare case of atypical pneumonia due to a non- pneumophila Legionella sp. that occurred in a young patient with systemic lupus erythematosus. In spite of aggressive treatment, the patient died 24 h following admission to the intensive care unit. Legionella longbeachae was cultured from respiratory tract specimens and identified to the genus level by PCR and to the species level by an immunofluorescence test. Since most current laboratory tests for Legionella spp., including urinary antigen and serology, cannot detect infections caused by non- pneumophila Legionella spp., culture on legionella-selective media should be strongly considered when diagnosing immunosuppressed patients with pneumonia.


Assuntos
Legionella longbeachae/isolamento & purificação , Legionelose/diagnóstico , Lúpus Eritematoso Sistêmico/imunologia , Adulto , Infecções Comunitárias Adquiridas/complicações , Infecções Comunitárias Adquiridas/diagnóstico , Infecções Comunitárias Adquiridas/imunologia , Progressão da Doença , Evolução Fatal , Feminino , Humanos , Hospedeiro Imunocomprometido , Legionelose/complicações , Legionelose/imunologia , Lúpus Eritematoso Sistêmico/complicações , Lúpus Eritematoso Sistêmico/diagnóstico , Doenças Raras , Medição de Risco , Índice de Gravidade de Doença
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