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1.
Antioxidants (Basel) ; 13(2)2024 Jan 26.
Artigo em Inglês | MEDLINE | ID: mdl-38397754

RESUMO

Lung cancer (LC) constitutes an important cause of death among patients with Chronic Obstructive Pulmonary Disease (COPD). Both diseases may share pathobiological mechanisms related to oxidative damage and cellular senescence. In this study, the potential value of leucocyte telomere length, a hallmark of aging, and 8-OHdG concentrations, indicative of oxidative DNA damage, as risk biomarkers of LC was evaluated in COPD patients three years prior to LC diagnosis. Relative telomere length measured using qPCR and serum levels of 8-OHdG were determined at the baseline in 99 COPD smokers (33 with LC and 66 age-matched COPD without LC as controls). Of these, 21 COPD with LC and 42 controls had the biomarkers measured 3 years before. Single nucleotide variants (SNVs) in TERT, RTEL, and NAF1 genes were also determined. COPD cases were evaluated, which showed greater telomere length (p < 0.001) and increased serum 8-OHdG levels (p = 0.004) three years prior to LC diagnosis compared to the controls. This relationship was confirmed at the time of LC diagnosis. No significant association was found between the studied SNVs in cases vs. controls. In conclusion, this preliminary study shows that longer leucocyte telomere length and increased 8-OHdG serum levels can be useful as early biomarkers of the risk for future lung cancer development among COPD patients.

2.
Front Pharmacol ; 14: 1184457, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37533632

RESUMO

Introduction: The use of opioids has increased markedly in the past decades in European countries, especially for treatment of non-cancer pain including painful chronic musculoskeletal conditions. However, there are some notable differences in the relative levels of use between geographical areas and some distinct, context-specific patterns of weak and strong opioid use. The aim of this work is to describe real world trends in dosage forms and population exposure in the prescription opioid use on isolated geographically area: The Canary Islands of Gran Canaria, Lanzarote and Fuerteventura, Spain. For this, several factors such as living in a rural or urban area, population over 65 years of age, population density or socioeconomic status were analyzed. Methods: Data were extracted from the wholesalers who supply the community pharmacies at the population level. Prescription opioid use was measured as defined daily doses (DDD) per 1,000 inhabitants per day. A model based on covariance analysis with two nested fixed factors and one co-variable was used for contrast analysis at different level. Results: The overall DDD per 1000 inhabitants per day and year variation rate in Spain was very similar to that obtained for Gran Canaria and Fuerteventura (0.967 vs. 1.006), although the levels of dispensation were different (14.75 versus 18.24 for Gran Canaria and 12.7 for Fuerteventura, respectively). Lanzarote is completely different in all issues, where the opioid consumption rate remained stable during the study period, but with a decreasing tendency. The dispensation level of strong opioids varied between islands, from 56.41% for Fuerteventura vs. 17.61% for Gran Canaria, although these values remained stable. Tramadol with acetaminophen and Tramadol in monotherapy were the most consumed forms of the weak opioids, whereas Buprenorphine was the most used strong opioid followed by Fentanyl, although demand for it varied between islands, the transdermal formulations were the most frequent pharmaceutical preparation. Conclusion: The differences in prescription opioid use are most likely explained by the opioid prescribing practices in each island, whereas factors such urbanicity level, population age, population density and status socioeconomic does not help to explain the differences in prescription opioid use across rural and urban areas.

3.
Int J Mol Sci ; 24(15)2023 Aug 04.
Artigo em Inglês | MEDLINE | ID: mdl-37569812

RESUMO

Lung cancer (LC) is the most common cause of cancer death, with 75% of cases being diagnosed in late stages. This study aimed to determine potential miRNAs as biomarkers for the early detection of LC in chronic obstructive pulmonary disease (COPD) cases. Ninety-nine patients were included, with registered clinical and lung function parameters followed for 6 years. miRNAs were determined in 16 serum samples from COPD patients (four with LC and four controls) by next generation sequencing (NGS) at LC diagnosis and 3 years before. The validation by qPCR was performed in 33 COPD-LC patients and 66 controls at the two time points. Over 170 miRNAs (≥10 TPM) were identified; among these, miR-224-5p, miR-206, miR-194-5p, and miR-1246 were significantly dysregulated (p < 0.001) in COPD-LC 3 years before LC diagnosis when compared to the controls. The validation showed that miR-1246 and miR-206 were differentially expressed in COPD patients who developed LC three years before (p = 0.035 and p = 0.028, respectively). The in silico enrichment analysis showed miR-1246 and miR-206 to be linked to gene mediators in various signaling pathways related to cancer. Our study demonstrated that miR-1246 and miR-206 have potential value as non-invasive biomarkers of early LC detection in COPD patients who could benefit from screening programs.


Assuntos
Neoplasias Pulmonares , MicroRNAs , Doença Pulmonar Obstrutiva Crônica , Humanos , Perfilação da Expressão Gênica , Neoplasias Pulmonares/diagnóstico , Neoplasias Pulmonares/genética , MicroRNAs/genética , Doença Pulmonar Obstrutiva Crônica/diagnóstico , Doença Pulmonar Obstrutiva Crônica/genética , Detecção Precoce de Câncer
4.
Eur J Pharm Biopharm ; 180: 11-22, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-36162636

RESUMO

Statins are effective sterol lowering agents with high amoebicidal activity. Nevertheless, due to their poor aqueous solubility, they remain underused especially in eye drop formulation. The aim of the present study is to develop Pitavastatin loaded nanoparticles suitable for ophthalmic administration and designed for the management of Acanthamoeba Keratitis. These nanocarriers are aimed to solve both the ophthalmic route-associated problems and the limited aqueous drug solubility issues of Pitavastatin. Nanoparticles were obtained by a nanoprecipitation-solvent displacement method and their amoebicidal activity was evaluated against four strains of Acanthamoeba: A. castellanii Neff, A. polyphaga, A. griffini and A. quina. In Acanthamoeba polyphaga, the effect of the present nanoparticles was investigated with respect to the microtubule distribution and several programmed cell death features. Nanoparticles were able to eliminate all the tested strains and Acanthamoeba polyphaga was determined to be the most resistance strain. Nanoparticles induced chromatin condensation, autophagic vacuoles and mitochondria dysfunction.


Assuntos
Ceratite por Acanthamoeba , Acanthamoeba , Amebicidas , Nanopartículas , Humanos , Ceratite por Acanthamoeba/tratamento farmacológico , Administração Oftálmica , Amebicidas/farmacologia , Amebicidas/uso terapêutico , Morte Celular , Autofagia
5.
Endocrine ; 37(3): 430-9, 2010 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-20960164

RESUMO

Women with ovarian cancer have a low survival rate and develop resistance to chemotherapy, so new approaches to treatment are needed. We unexpectedly found administration of a replication-deficient adenovirus containing human growth hormone sequences (AdXGH) was beneficial in a mouse model of human ovarian cancer. Intraperitoneal injections of AdXGH prolonged median survival from a mean of 31 ± 1.2 to 40 ± 1.4 days in immunodeficient SCID mice given SKOV3.ip1 human ovarian cancer cells in the peritoneal cavity. Adenovirus containing human prolactin or del32-71growth hormone sequences had no effect. Repeated injection of growth hormone or implantation of tablets with sustained growth hormone release did not increase survival. Control mice had overlapping tumors throughout the peritoneal cavity and liver and frequent lung metastases 24 days after tumor cell injection. Mice that received two injections of AdXGH had no lung metastases. Mice that received four injections had no lung or liver metastases and peritoneal fibrosis. They did not survive longer than mice that received two injections, but they had enlarged livers with hepatocellular changes, indicating that a limitation of increasing the dose is liver toxicity.


Assuntos
Adenoviridae/genética , Hormônio do Crescimento Humano/genética , Neoplasias Ovarianas/terapia , Animais , Antineoplásicos/uso terapêutico , Sequência de Bases , Carboplatina/uso terapêutico , Terapia Combinada , Modelos Animais de Doenças , Feminino , Humanos , Injeções Intraperitoneais , Camundongos , Camundongos SCID , Neoplasias Ovarianas/tratamento farmacológico , Paclitaxel/uso terapêutico
6.
Talanta ; 78(3): 781-9, 2009 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-19269428

RESUMO

Size-exclusion chromatography (SEC) coupled with online laser light-scattering (LS) and refractive index (RI) detection provides an excellent approach to determine the molecular weights (Mw) of proteins by the "two-detector" approach. Mw is determined only at the maximum of a peak, using either peak heights or area ratio from the two detectors. However, proper calibration of the SEC/LS/RI system is critical to obtain high precision. Today, an essential part of any analysis is to evaluate the uncertainty associated with the method. Basically, it is possible to distinguish between factors related to signal nature, precision and those due to signal processing. Given the signal of interest is the peak height or area ratio from two detectors, the signal ratio uncertainty was calculated using the random propagation of error formula. In this case, the effect of signal correlation was evaluated to avoid the uncertainty overestimation. In the second case, the sources of uncertainty affecting analytical measurement were estimated with the information from the precision assessment. For this, two designs with two-factor fully nested were followed for each method. Finally, the contributions from various uncertainty sources related with calibration are also analysed in detail. There are in fact only three main sources of measurement uncertainty: intermediate precision, calibration and repeatability. Of these, method precision is always the greatest, regardless of approach. For all proteins and peptides studied, the Mw calculated using both methods are close to the theoretical results, independently of the design, but the contributions of individual terms to combined uncertainty depend on both the design and method used. For example, the combined uncertainty varied between 223 and 813.2 Da for carbonic anhydrase, although higher values were found for human insulin and ovalbumin dimer. Other considerations that can have a significant impact on the results are discussed. The reproducibility of the two methods versus that based on ASTRA software used as reference method was performed using the concordance correlation coefficient. The methods' reproducibility depends on the permitted losses in precision and accuracy.


Assuntos
Cromatografia em Gel/normas , Peptídeos/química , Proteínas/química , Calibragem , Anidrases Carbônicas , Cromatografia em Gel/instrumentação , Cromatografia em Gel/métodos , Humanos , Insulina , Luz , Peso Molecular , Ovalbumina , Refratometria , Reprodutibilidade dos Testes , Espalhamento de Radiação
7.
Curr Drug Discov Technol ; 1(3): 229-42, 2004 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-16472250

RESUMO

The proliferation of new peptides and proteins requiring characterisation is a direct result of recent advances in genomics and proteomics, but protein aggregation is particular problem in the biotechnology industry, where aggregation is encountered throughout the lifetime of a therapeutic protein, including during refolding, purification, sterilization, shipping, and storage process. To ensure that it meets quality standards, the size, molecular weight and/or molecular weight distribution, and aggregate state must be accurately determined. Traditional analytical methods for determining molecular weight include size-exclusion chromatography (SEC), gel electrophoresis, analytical ultracentrifugation and time-of-flight mass spectrometry. These technologies are time-consuming (some take days), provide data based on relative standards, or cannot characterise very high molecular weight aggregates. Laser light-scattering (LS) detection coupled with SEC system have been used for over a decade to determine the size and molecular weight of bio-molecules such as proteins, peptides, polysaccharides, oligonucleotides, and antibodies, the method of choice being for molar mass determinations and the study of self-association and heterogeneous interaction under native, equilibrium conditions in solution. The purpose of the current review is to describe and discuss the capability of the SEC/LS system to determine absolute molecular weight of proteins and their complexes and the association state of the conjugate, either with itself or with protein receptor/ligands. For this, the "two or three detector" methods, each with its advantages and limitations, can be used to calculate the molecular weight of a simple protein or glycoprotein, and the stoichiometry of their complexes. Also, some alternative techniques for determining the molecular weight are discussed in this review. Applications of all these methodologies are described.


Assuntos
Peptídeos/análise , Proteínas/análise , Algoritmos , Glicoproteínas/análise , Lasers , Ligantes , Espectrometria de Massas , Espalhamento de Radiação , Espectrofotometria Ultravioleta , Ultracentrifugação
8.
Peptides ; 23(9): 1527-35, 2002 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-12217412

RESUMO

SPf66 is the first chemically synthesized peptide to elicit a partial protective immune response against malaria. Size-exclusion chromatography (SEC) with multi-angle laser light-scattering (MALLS) detection and hydrogen/deuterium (H/D) exchange monitored by (matrix-assisted laser desorption/ionization) MALDI-TOF (time-of-flight) mass spectrometry (MS) were used to assess the conformation and stability in aqueous solution after storage at different temperatures. Moreover, the feasible conformational changes of this peptide were also measured by circular dichroism (CD)-spectroscopy. The absolute molecular weight of SPf66 monomer and dimer species were 4765 and 8960Da using SEC with MALLS detection, and 4643 and 9490Da by MALDI-TOF MS, the discrepancy being between both methods lower than 5.7%, a value quite close to those found in other proteins. The results from H/D exchange monitored by MALDI-TOF MS and CD-spectroscopy show that the SPf66 monomer lacks ordered structure, whereas the SPf66 dimer species presents segments of secondary structure as a determined by CD measurements.


Assuntos
Proteínas de Protozoários/química , Proteínas Recombinantes , Cromatografia , Dicroísmo Circular/métodos , Dimerização , Luz , Vacinas Antimaláricas/química , Peptídeos/química , Estrutura Secundária de Proteína , Espalhamento de Radiação , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz/métodos
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