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1.
Genome Med ; 16(1): 54, 2024 Apr 08.
Artigo em Inglês | MEDLINE | ID: mdl-38589970

RESUMO

BACKGROUND: Lung cancer is the leading cause of cancer-related death in the world. In contrast to many other cancers, a direct connection to modifiable lifestyle risk in the form of tobacco smoke has long been established. More than 50% of all smoking-related lung cancers occur in former smokers, 40% of which occur more than 15 years after smoking cessation. Despite extensive research, the molecular processes for persistent lung cancer risk remain unclear. We thus set out to examine whether risk stratification in the clinic and in the general population can be improved upon by the addition of genetic data and to explore the mechanisms of the persisting risk in former smokers. METHODS: We analysed transcriptomic data from accessible airway tissues of 487 subjects, including healthy volunteers and clinic patients of different smoking statuses. We developed a computational model to assess smoking-associated gene expression changes and their reversibility after smoking is stopped, comparing healthy subjects to clinic patients with and without lung cancer. RESULTS: We find persistent smoking-associated immune alterations to be a hallmark of the clinic patients. Integrating previous GWAS data using a transcriptional network approach, we demonstrate that the same immune- and interferon-related pathways are strongly enriched for genes linked to known genetic risk factors, demonstrating a causal relationship between immune alteration and lung cancer risk. Finally, we used accessible airway transcriptomic data to derive a non-invasive lung cancer risk classifier. CONCLUSIONS: Our results provide initial evidence for germline-mediated personalized smoke injury response and risk in the general population, with potential implications for managing long-term lung cancer incidence and mortality.


Assuntos
Neoplasias Pulmonares , Humanos , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/metabolismo , Fumar/efeitos adversos , Fumar/genética , Pulmão/metabolismo , Nicotiana , Mucosa Nasal/metabolismo , Transcriptoma
2.
Am J Respir Crit Care Med ; 208(10): 1075-1087, 2023 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-37708400

RESUMO

Rationale: IL-33 is a proinflammatory cytokine thought to play a role in the pathogenesis of asthma and chronic obstructive pulmonary disease (COPD). A recent clinical trial using an anti-IL-33 antibody showed a reduction in exacerbation and improved lung function in ex-smokers but not current smokers with COPD. Objectives: This study aimed to understand the effects of smoking status on IL-33. Methods: We investigated the association of smoking status with the level of gene expression of IL-33 in the airways in eight independent transcriptomic studies of lung airways. Additionally, we performed Western blot analysis and immunohistochemistry for IL-33 in lung tissue to assess protein levels. Measurements and Main Results: Across the bulk RNA-sequencing datasets, IL-33 gene expression and its signaling pathway were significantly lower in current versus former or never-smokers and increased upon smoking cessation (P < 0.05). Single-cell sequencing showed that IL-33 is predominantly expressed in resting basal epithelial cells and decreases during the differentiation process triggered by smoke exposure. We also found a higher transitioning of this cellular subpopulation into a more differentiated cell type during chronic smoking, potentially driving the reduction of IL-33. Protein analysis demonstrated lower IL-33 levels in lung tissue from current versus former smokers with COPD and a lower proportion of IL-33-positive basal cells in current versus ex-smoking controls. Conclusions: We provide strong evidence that cigarette smoke leads to an overall reduction in IL-33 expression in transcriptomic and protein level, and this may be due to the decrease in resting basal cells. Together, these findings may explain the clinical observation that a recent antibody-based anti-IL-33 treatment is more effective in former than current smokers with COPD.


Assuntos
Doença Pulmonar Obstrutiva Crônica , Fumantes , Humanos , Interleucina-33/genética , Fumar/genética , Doença Pulmonar Obstrutiva Crônica/patologia , Perfilação da Expressão Gênica
3.
bioRxiv ; 2023 Jul 04.
Artigo em Inglês | MEDLINE | ID: mdl-37461506

RESUMO

The fitness effects of new mutations determine key properties of evolutionary processes. Beneficial mutations drive evolution, yet selection is also shaped by the frequency of small-effect deleterious mutations, whose combined effect can burden otherwise adaptive lineages and alter evolutionary trajectories and outcomes in clonally evolving organisms such as viruses, microbes, and tumors. The small effect sizes of these important mutations have made accurate measurements of their rates difficult. In microbes, assessing the effect of mutations on growth can be especially instructive, as this complex phenotype is closely linked to fitness in clonally evolving organisms. Here, we perform high-throughput time-lapse microscopy on cells from mutation-accumulation strains to precisely infer the distribution of mutational effects on growth rate in the budding yeast, Saccharomyces cerevisiae. We show that mutational effects on growth rate are overwhelmingly negative, highly skewed towards very small effect sizes, and frequent enough to suggest that deleterious hitchhikers may impose a significant burden on evolving lineages. By using lines that accumulated mutations in either wild-type or slippage repair-defective backgrounds, we further disentangle the effects of two common types of mutations, single-nucleotide substitutions and simple sequence repeat indels, and show that they have distinct effects on yeast growth rate. Although the average effect of a simple sequence repeat mutation is very small (~0.3%), many do alter growth rate, implying that this class of frequent mutations has an important evolutionary impact.

4.
Artigo em Inglês | MEDLINE | ID: mdl-36901230

RESUMO

The ability to drive depends on the motor, visual, and cognitive functions, which are necessary to integrate information and respond appropriately to different situations that occur in traffic. The study aimed to evaluate older drivers in a driving simulator and identify motor, cognitive and visual variables that interfere with safe driving through a cluster analysis, and identify the main predictors of traffic crashes. We analyzed the data of older drivers (n = 100, mean age of 72.5 ± 5.7 years) recruited in a hospital in São Paulo, Brazil. The assessments were divided into three domains: motor, visual, and cognitive. The K-Means algorithm was used to identify clusters of individuals with similar characteristics that may be associated with the risk of a traffic crash. The Random Forest algorithm was used to predict road crash in older drivers and identify the predictors (main risk factors) related to the outcome (number of crashes). The analysis identified two clusters, one with 59 participants and another with 41 drivers. There were no differences in the mean of crashes (1.7 vs. 1.8) and infractions (2.6 vs. 2.0) by cluster. However, the drivers allocated in Cluster 1, when compared to Cluster 2, had higher age, driving time, and braking time (p < 0.05). The random forest performed well (r = 0.98, R2 = 0.81) in predicting road crash. Advanced age and the functional reach test were the factors representing the highest risk of road crash. There were no differences in the number of crashes and infractions per cluster. However, the Random Forest model performed well in predicting the number of crashes.


Assuntos
Condução de Veículo , Humanos , Idoso , Estudos Transversais , Brasil , Condução de Veículo/psicologia , Acidentes de Trânsito , Algoritmos
5.
G3 (Bethesda) ; 13(3)2023 03 09.
Artigo em Inglês | MEDLINE | ID: mdl-36529906

RESUMO

Mutations in simple sequence repeat loci underlie many inherited disorders in humans, and are increasingly recognized as important determinants of natural phenotypic variation. In eukaryotes, mutations in these sequences are primarily repaired by the MutSß mismatch repair complex. To better understand the role of this complex in mismatch repair and the determinants of simple sequence repeat mutation predisposition, we performed mutation accumulation in yeast strains with abrogated MutSß function. We demonstrate that mutations in simple sequence repeat loci in the absence of mismatch repair are primarily deletions. We also show that mutations accumulate at drastically different rates in short (<8 bp) and longer repeat loci. These data lend support to a model in which the mismatch repair complex is responsible for repair primarily in longer simple sequence repeats.


Assuntos
Reparo de Erro de Pareamento de DNA , Saccharomyces cerevisiae , Humanos , Saccharomyces cerevisiae/genética , Mutagênese , Mutação , Reparo de Erro de Pareamento de DNA/genética , Repetições de Microssatélites , Reparo do DNA
7.
BMC Vet Res ; 12: 24, 2016 Feb 02.
Artigo em Inglês | MEDLINE | ID: mdl-26838095

RESUMO

BACKGROUND: Equine sarcoids are locally invasive, fibroblastic benign skin tumors. Bovine papillomavirus type-1 (BPV-1) and/or Bovine papillomavirus type-2 (BPV-2) are believed to be the causative agent of sarcoids, although the mechanisms by which the virus induce the tumor are still poorly understood. We hypothesized that in genetically predisposed equines latent BPV infection may be reactivated by immunosoppression and/or mechanical injury leading to a form of pathologic wound which may transform into a sarcoid. In this study, we investigated in 25 equine sarcoids and in five normal skin samples the histological features and evaluated the immunohistochemical and molecular expression of type I and type III Collagen, vimentin (VIM), alfa Smooth Muscle Actin (α-SMA), Matrix Metalloproteinase (MMPs) -2, 9, 14 and tissue inhibitor of metalloproteinase 2 (TIMP-2). RESULTS: In 64% of investigated sarcoids, type I collagen staining was stronger than that of type III collagen. In 80% of sarcoids, SFs were strongly positive for vimentin and negative for α-SMA; the remaining sarcoid samples (20%) showed 70-80% of SFs labeled for vim and approximately 20-30% labeled for α-SMA. Moreover, all sarcoid specimen showed a variable staining pattern (weak to moderate) for MMP-9 and MMP-14, and a moderate to strong staining for MMP-2 and TIMP-2. Biochemical analysis confirmed immunohistochemical results and showed in sarcoids, for the first time, the cleaved form of MMP9, the 35 KDa active species for MMP-9. CONCLUSIONS: This study revealed that in equine sarcoids exhibit an altered turnover of the Extracellular Matrix (ECM) deposition and degradation, as result of an altered expression of MMPs and TIMPs. Therefore, these observations seem to confirm that the basic mechanism for growth of equine sarcoids could be a neoplastic transformation during wound healing.


Assuntos
Matriz Extracelular/patologia , Doenças dos Cavalos/patologia , Neoplasias Cutâneas/veterinária , Animais , Matriz Extracelular/metabolismo , Doenças dos Cavalos/metabolismo , Cavalos , Inibidores de Metaloproteinases de Matriz/metabolismo , Metaloproteinases da Matriz/metabolismo , Neoplasias Cutâneas/metabolismo , Neoplasias Cutâneas/patologia , Inibidor Tecidual de Metaloproteinase-2/metabolismo
8.
Sci Rep ; 6(1): 18, 2016 Dec 21.
Artigo em Inglês | MEDLINE | ID: mdl-28442708

RESUMO

In contrast to the widely accepted consensus of the existence of a single RNA polymerase in bacteria, several actinomycetes have been recently shown to possess two forms of RNA polymerases due the to co-existence of two rpoB paralogs in their genome. However, the biological significance of the rpoB duplication is obscure. In this study we have determined the genome sequence of the lipoglycopeptide antibiotic A40926 producer Nonomuraea gerenzanensis ATCC 39727, an actinomycete with a large genome and two rpoB genes, i.e. rpoB(S) (the wild-type gene) and rpoB(R) (the mutant-type gene). We next analyzed the transcriptional and metabolite profiles in the wild-type gene and in two derivative strains over-expressing either rpoB(R) or a mutated form of this gene to explore the physiological role and biotechnological potential of the "mutant-type" RNA polymerase. We show that rpoB(R) controls antibiotic production and a wide range of metabolic adaptive behaviors in response to environmental pH. This may give interesting perspectives also with regard to biotechnological applications.


Assuntos
Actinomycetales/genética , Proteínas de Bactérias/genética , RNA Polimerases Dirigidas por DNA/genética , Genoma Bacteriano , Transcriptoma , Actinomycetales/metabolismo , Antibacterianos/biossíntese , Concentração de Íons de Hidrogênio , Mutação , Teicoplanina/análogos & derivados , Teicoplanina/biossíntese
9.
Int J Geriatr Psychiatry ; 28(6): 632-9, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-22968978

RESUMO

OBJECTIVE: The aim of this research was to investigate relationships between cognitive function and non-invasive, repeatable cardiac parameters in elderly subjects suffering from mild cognitive impairment (MCI) or Alzheimer's disease (AD). METHODS: Two hundred and twenty-four community-living elderly subjects, 31 AD patients, 77 MCI patients, and 116 cognitively normal subjects (CNS), were evaluated for cognitive abilities (Mini Mental State Examination score (MMSE)) and for electrocardiographic [corrected heart rate QT interval dispersion (QTcD)] and echocardiographic [Left ventricular ejection fraction (LVEF)] parameters. RESULTS: Mean values of LVEF were not significantly different between the three groups; QTcD mean values were significantly lower in CNS group than in subjects with MCI and AD. The Pearson Product Moment Correlation test, carried out in the three study groups, showed a significant inverse correlation between QTcD and MMSE score (r = -0.357; p < 0.01) in the group of MCI patients, only. In multivariable-adjusted linear regression tests, QTcD (p = 0.030) and education (p = 0.021) are associated with MMSE score in MCI group. Only the parameter of education appears to predict MMSE in CNS group; none of these parameters appear to predict MMSE in the group of patients with AD. CONCLUSION: The association between QTcD and MMSE requires cautious interpretation and further extensive investigation. However, if confirmed by longitudinal studies, the finding could play a role in the management of the subjects with MCI.


Assuntos
Disfunção Cognitiva/fisiopatologia , Demência/fisiopatologia , Frequência Cardíaca/fisiologia , Idoso , Idoso de 80 Anos ou mais , Análise de Variância , Cognição/fisiologia , Disfunção Cognitiva/complicações , Demência/etiologia , Progressão da Doença , Ecocardiografia , Eletrocardiografia , Feminino , Humanos , Itália , Masculino , Valor Preditivo dos Testes , Função Ventricular Esquerda/fisiologia
11.
Am J Med Sci ; 333(3): 154-60, 2007 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-17496733

RESUMO

BACKGROUND: Increased plasma levels of fibrinogen are been associated with an increased risk of cardiovascular accident. We aimed at verifying whether the changes of fibrinogen levels are associated with red blood cell (and/or hemoglobin) concentration. METHODS: A group of 381 carefully selected healthy volunteers (219 male and 162 female), aged from 18 to 101 years, were enrolled in this study. Fasting blood samples were taken and all measurements (fibrinogen plasma level, whole blood viscosity, hemoglobin concentration, hematocrit value, red blood cell and white blood cell count, platelet count, glucose, total cholesterol and triglycerides plasma concentration, and C-reactive protein level) were obtained with standardized methodology using appropriate equipment, procedures, and controls. RESULTS AND CONCLUSIONS: In the male but not in the female group, plasma fibrinogen concentration inversely correlated with hemoglobin (P < 0.0001) and hematocrit value (P < 0.01). In a post hoc analysis, plasma fibrinogen level inversely correlated with hemoglobin in the subgroup of the 93 premenopausal women and directly correlated with age and inversely correlated with platelet count in the subgroup of the 69 postmenopausal women. Results of multiple regression analysis revealed that in all the subjects, except in the postmenopausal women, hemoglobin level is an independent predictor of fibrinogen plasma level. Considering the physiopathologic role of increased plasma fibrinogen concentration and the scarcity of pharmacologic approaches to decrease its level, these findings could be important in designing a preventive therapy of cardiovascular disease.


Assuntos
Fibrinogênio/análise , Hemoglobinas/análise , Adulto , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Contagem de Células Sanguíneas , Análise Química do Sangue , Feminino , Hematócrito , Humanos , Masculino , Pessoa de Meia-Idade , Análise de Regressão , Fatores Sexuais
12.
Med. reabil ; 23(2): 25-28, maio-ago. 2004.
Artigo em Português | LILACS | ID: lil-392321

RESUMO

Relata os resultados obtidos no treino de marcha com equipamento de suuspensão em cinco pacientes portadores de lesão medular, com idade média de 27,6 anos, média de tempo de lesão de 5 anos, 2 com lesão T12 e 3 com lesão C7, sendo 4 icompletos e 1 completo. O treino foi realizado com uma estrutura capaz de sustentar o peso do paciente, em sessões semanais de aproximadamente 50 minutos, numa média de 12,4 sessões. Os pacientes apresentaram melhora da marcha com o treino, porém há necessidade de um estudo controlado, com número maior de casos


Assuntos
Marcha , Locomoção , Reabilitação , Traumatismos da Medula Espinal
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