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1.
Curr Atheroscler Rep ; 26(7): 249-262, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38795275

RESUMO

PURPOSE OF REVIEW: Sleep is an important component of cardiovascular (CV) health. This review summarizes the complex relationship between sleep and CV disease (CVD). Additionally, we describe the data supporting the treatment of sleep disturbances in preventing and treating CVD. RECENT FINDINGS: Recent guidelines recommend screening for obstructive sleep apnea in patients with atrial fibrillation. New data continues to demonstrate the importance of sleep quality and duration for CV health. There is a complex bidirectional relationship between sleep health and CVD. Sleep disturbances have systemic effects that contribute to the development of CVD, including hypertension, coronary artery disease, heart failure, and arrhythmias. Additionally, CVD contributes to the development of sleep disturbances. However, more data are needed to support the role of screening for and treatment of sleep disorders for the prevention of CVD.


Assuntos
Doenças Cardiovasculares , Transtornos do Sono-Vigília , Sono , Humanos , Doenças Cardiovasculares/fisiopatologia , Doenças Cardiovasculares/prevenção & controle , Transtornos do Sono-Vigília/fisiopatologia , Transtornos do Sono-Vigília/complicações , Sono/fisiologia , Apneia Obstrutiva do Sono/complicações , Apneia Obstrutiva do Sono/fisiopatologia , Apneia Obstrutiva do Sono/terapia , Qualidade do Sono , Fatores de Risco
2.
Molecules ; 29(18)2024 Sep 18.
Artigo em Inglês | MEDLINE | ID: mdl-39339429

RESUMO

Redox metabolism is an integral part of the glutathione system, encompassing reduced and oxidized glutathione, hydrogen peroxide, and associated enzymes. This core process orchestrates a network of thiol antioxidants like thioredoxins and peroxiredoxins, alongside critical thiol-containing proteins such as mercaptoalbumin. Modifications to thiol-containing proteins, including oxidation and glutathionylation, regulate cellular signaling influencing gene activities in inflammation and carcinogenesis. Analyzing thiol antioxidants, especially glutathione, in biological fluids offers insights into pathological conditions. This review discusses the analytical methods for biothiol determination, mainly in blood plasma. The study includes all key methodological aspects of spectroscopy, chromatography, electrochemistry, and mass spectrometry, highlighting their principles, benefits, limitations, and recent advancements that were not included in previously published reviews. Sample preparation and factors affecting thiol antioxidant measurements are discussed. The review reveals that the choice of analytical procedures should be based on the specific requirements of the research. Spectrophotometric methods are simple and cost-effective but may need more specificity. Chromatographic techniques have excellent separation capabilities but require longer analysis times. Electrochemical methods enable real-time monitoring but have disadvantages such as interference. Mass spectrometry-based approaches have high sensitivity and selectivity but require sophisticated instrumentation. Combining multiple techniques can provide comprehensive information on thiol antioxidant levels in biological fluids, enabling clearer insights into their roles in health and disease. This review covers the time span from 2010 to mid-2024, and the data were obtained from the SciFinder® (ACS), Google Scholar (Google), PubMed®, and ScienceDirect (Scopus) databases through a combination search approach using keywords.


Assuntos
Antioxidantes , Compostos de Sulfidrila , Humanos , Antioxidantes/análise , Antioxidantes/metabolismo , Antioxidantes/química , Compostos de Sulfidrila/análise , Compostos de Sulfidrila/sangue , Líquidos Corporais/química , Líquidos Corporais/metabolismo , Espectrometria de Massas/métodos , Oxirredução , Animais , Glutationa/análise , Glutationa/sangue , Técnicas Eletroquímicas/métodos
3.
Inorg Chem ; 61(37): 14705-14717, 2022 Sep 19.
Artigo em Inglês | MEDLINE | ID: mdl-36047922

RESUMO

We report herein a Pt(IV) prodrug with metronidazole in axial positions Pt-Mnz. The nitroaromatic axial ligand was conjugated with a cisplatin scaffold to irreversibly reduce under hypoxic conditions, thereby retaining the Pt(IV) prodrug in the area of hypoxia. X-ray near-edge adsorption spectroscopy (XANES) on dried drug-preincubated tumor cell samples revealed a gradual release of cisplatin from the Pt-Mnz prodrug instead of rapid intracellular degradation. The ability of the prodrug to penetrate into three-dimensional (3D) spheroid cellular cultures was evaluated by a novel electrochemical assay via a platinum-coated carbon nanoelectrode, capable of single-cell measurements. Using a unique technique of electrochemical measurements in single tumor spheroids, we were able to both detect the real-time response of the axial ligand to hypoxia and establish the depth of penetration of the drug into the tumor model.


Assuntos
Antineoplásicos , Pró-Fármacos , Antineoplásicos/química , Antineoplásicos/farmacologia , Carbono , Linhagem Celular Tumoral , Cisplatino/química , Humanos , Hipóxia , Ligantes , Metronidazol/farmacologia , Platina/química , Pró-Fármacos/química , Pró-Fármacos/farmacologia
4.
Nucleic Acids Res ; 47(14): 7348-7362, 2019 08 22.
Artigo em Inglês | MEDLINE | ID: mdl-31194876

RESUMO

During differentiation of the Tetrahymena thermophila somatic nucleus, its germline-derived DNA undergoes extensive reorganization including the removal of ∼50 Mb from thousands of loci called internal eliminated sequences (IESs). IES-associated chromatin is methylated on lysines 9 and 27 of histone H3, marking newly formed heterochromatin for elimination. To ensure that this reorganized genome maintains essential coding and regulatory sequences, the boundaries of IESs must be accurately defined. In this study, we show that the developmentally expressed protein encoded by Lia3-Like 1 (LTL1) (Ttherm_00499370) is necessary to direct the excision boundaries of particular IESs. In ΔLTL1 cells, boundaries of eliminated loci are aberrant and heterogeneous. The IESs regulated by Ltl1 are distinct from those regulated by the guanine-quadruplex binding Lia3 protein. Ltl1 has a general affinity for double stranded DNA (Kd ∼ 350 nM) and binds specifically to a 50 bp A+T rich sequence flanking each side of the D IES (Kd ∼ 43 nM). Together these data reveal that Ltl1 and Lia3 control different subsets of IESs and that their mechanisms for flanking sequence recognition are distinct.


Assuntos
DNA de Protozoário/genética , Proteínas de Ligação a DNA/genética , Heterocromatina/genética , Proteínas de Protozoários/genética , Tetrahymena thermophila/genética , Sequência de Aminoácidos , Sítios de Ligação/genética , Linhagem Celular , DNA de Protozoário/metabolismo , Proteínas de Ligação a DNA/metabolismo , Regulação da Expressão Gênica , Técnicas de Inativação de Genes , Heterocromatina/metabolismo , Ligação Proteica , Proteínas de Protozoários/metabolismo , Homologia de Sequência de Aminoácidos , Tetrahymena thermophila/citologia , Tetrahymena thermophila/metabolismo
5.
Anal Chem ; 91(12): 7495-7499, 2019 06 18.
Artigo em Inglês | MEDLINE | ID: mdl-31117405

RESUMO

We first report on constant potential (dc) amperometric flow-injection analysis (FIA) transduced by electroactive (conductive) polymers. Amperometric response is caused by the polymer recharging in order to maintain the electrode potential at a constant level when (i) ions are crossing the film|solution interface and polarizing electrode|film interface or (ii) ions or neutral molecules are specifically interacting with the polymer recharging it. The response under constant solution flow is a current peak and in flow-injection mode is a couple of current peaks directed opposite of the first sharp, analytically valuable peak. In both constant flow and flow-injection regimes, the peak current is dependent on analyte concentrations; obviously, the FIA mode provides more advantageous analytical characteristics. Constant potential amperometric flow-injection analysis is shown for boronate- and sulfate-functionalized polyanilines as well as for Prussian Blue, a member of the inorganic polymer family. As a proof of concept, the successful dc amperometric detection of lactate in human sweat with boronate-functionalized polyaniline has been shown. The proposed approach would revolutionize the field of conductive/electroactive polymer-supported ion sensing with the introduction of reliable and robust amperometry as a valuable alternative to existing potentiometry.

6.
Anal Chem ; 89(21): 11198-11202, 2017 11 07.
Artigo em Inglês | MEDLINE | ID: mdl-29065687

RESUMO

For noninvasive diagnostics of hypoxia, we propose the nonenzymatic sensor based on screen-printed structures with the working surface modified in course of electropolymerization of 3-aminophenylboronic acid (3-APBA) with imprinting of lactate. Impedimetric sensor allows lactate detection in the range from 3 mM to 100 mM with the detection limit of 1.5 mM; response time is 2-3 min. Sensor sensitivity remains unchanged within 6 months of storage unpacked in dry state at a room temperature, which is unachievable for enzyme based devices. Analysis of human sweat with poly(3-APBA) based sensor is possible due to (i) much higher lactate content compared to other polyols and (ii) high sensor selectivity (Klactateglucose < 3 × 10-2). Successful detection of lactate in human sweat by means of the poly(3-APBA) based sensor has been confirmed using the highly specific reference method based on lactate oxidase enzyme (correlation coefficient r > 0.9). The attractive performance characteristics of poly(3-APBA) based enzyme-free sensors justify their future use for noninvasive clinical analysis and sports medicine.


Assuntos
Técnicas Eletroquímicas/métodos , Ácido Láctico/análise , Suor/química , Ácidos Borônicos/química , Humanos , Limite de Detecção , Polimerização , Polímeros/química
7.
Anal Chem ; 86(23): 11690-5, 2014 Dec 02.
Artigo em Inglês | MEDLINE | ID: mdl-25363870

RESUMO

We report on the novel reagentless and label-free detection principle based on electroactive (conducting) polymers considering sensors for polyols, particularly, saccharides and hydroxy acids. Unlike the majority of impedimetric and conductometric (bio)sensors, which specific and unspecific signals are directed in the same way (resistance increase), making doubtful their real applications, the response of the reported system results in resistance decrease, which is directed oppositely to the background. The mechanism of the resistance decrease is the polyaniline self-doping, i.e., as an alternative to proton doping, an appearance of the negatively charged aromatic ring substituents in polymer chain. Negative charge "freezing" at the boron atom is indeed a result of complex formation with di- and polyols, specific binding. Changes in Raman spectra of boronate-substituted polyaniline after addition of glucose are similar to those caused by proton doping of the polymer. Thermodynamic data on interaction of the electropolymerized 3-aminophenylboronic acid with saccharides and hydroxy acids also confirm that the observed resistance decrease is due to polymer interaction with polyols. The first reported conductivity increase as a specific signal opens new horizons for reagentless affinity sensors, allowing the discrimination of specific affinity bindings from nonspecific interactions.

8.
Biosens Bioelectron ; 220: 114851, 2023 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-36345086

RESUMO

We report on the amperometric second-generation glucose test strips with the linear calibration range covering blood glucose concentrations. Chitosan membrane was used for immobilization of both enzyme and mediator in a single step. Optimal chitosan concentration in membrane-forming mixture corresponds to the highest enzyme activity and dramatically improved mediator adsorption in final membrane. On one hand, the immobilized glucose oxidase activation with an increase of the chitosan polymer content in the membrane has been noticed. On the other hand, positively charged chitosan matrix retains mediator (hexacyanoferrate (III) ion) in the membrane, due to its negative charge. Additionally, the excessive adsorption of the mediator on screen-printed electrodes coated with membranes was proved by means of cyclic voltammetry and impedance spectroscopy. Glucose test strips have been elaborated via single-step modification of the sensor support with the enzyme-mediator-polymer mixture. Apparently, the record linear calibration range from 1 mM to 50 mM glucose was achieved recording amperometric response at 5th second after potential was applied. The elaborated test strips have been validated through analysis of standard serum and blood samples. In whole blood test strips keep 84-98% of their sensitivity in buffer solution.


Assuntos
Técnicas Biossensoriais , Quitosana , Glucose Oxidase/química , Quitosana/química , Glucose/análise , Enzimas Imobilizadas/química , Técnicas Biossensoriais/métodos , Eletrodos , Polímeros , Testes Hematológicos
9.
Bioelectrochemistry ; 149: 108275, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36228395

RESUMO

We report on Prussian Blue based nanozymes, comparable in size with a natural enzyme peroxidase. Protein-sized nanoparticles have been synthesized in the course of reduction of ferric ion (Fe3+) and ferricyanide ([Fe(CN)6]3-) one-to-one mixture in reversed micelles (isooctane|AOT|water) used as templates. Aniline chosen as the best reductant for this aim has led to formation of composite (according to Raman spectroscopy) Prussian Blue - polyaniline nanoparticles. The protein-like size of the nanoparticles (∅ = 4 - 6 nm) has been confirmed by DLS and TEM imaging. Kinetic investigations of peroxidase-like activity in reversed micelles resulted in the catalytic rate constant belonging to the same size-dependence as regular bulk catalytically synthesized nanozymes (slope ≈ 2.6), allowing to denote the reported Prussian Blue nanoparticles synthesized in reversed micelles as nanozymes «artificial peroxidase¼. Hydrogen peroxide sensors made by dipping the suspension of the latter onto the electrode support, displayed two-fold higher sensitivity as compared to the Prussian Blue film-based ones. Protein-sized nanozymes «artificial peroxidase¼ would obviously provide an advantage over regular nanozymes in (bio)sensors and analytical kits.


Assuntos
Micelas , Peroxidase , Ferrocianetos , Catálise , Peroxidases , Peróxido de Hidrogênio , Corantes , Ferro
10.
ACS Appl Mater Interfaces ; 15(10): 12882-12894, 2023 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-36854172

RESUMO

Controlled photoreduction of Pt(IV) prodrugs is a challenging task due to the possibility of targeted light-controlled activation of anticancer agents without affecting healthy tissues. Also, a conjugation of photosensitizers and clinically used platinum drugs into one Pt(IV) prodrug allows combining photodynamic therapy and chemotherapy approaches into one molecule. Herein, we designed the cisplatin-based Pt(IV) prodrug Riboplatin with tetraacetylriboflavin in the axial position. A novel Pt(IV) prodrug is able to act both as a photodynamic therapy (PDT) agent through the conversion of ground-state 3O2 to excited-state 1O2 and as an agent of photoactivated chemotherapy (PACT) through releasing of cisplatin under gentle blue light irradiation, without the requirement of a reducing agent. The light-induced behavior of Riboplatin was investigated using an electrochemical sensor in MCF-7 tumor spheroids. Photocontrolled cisplatin release and ROS generation were detected electrochemically in real time. This appears to be the first confirmation of simultaneous photoactivated release of anticancer drug cisplatin and ROS from a dual-action Pt(IV) prodrug observed from the inside of living tumor spheroids.


Assuntos
Antineoplásicos , Pró-Fármacos , Cisplatino/farmacologia , Cisplatino/química , Pró-Fármacos/farmacologia , Pró-Fármacos/química , Espécies Reativas de Oxigênio , Antineoplásicos/farmacologia , Antineoplásicos/química , Platina/química , Linhagem Celular Tumoral
11.
Am Heart J Plus ; 15: 100135, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38558756

RESUMO

Background: Spontaneous coronary artery dissection (SCAD) is an important cause of acute coronary syndrome in young women. There is no consensus on optimal treatment, though a conservative approach including antiplatelet agents is commonly used. We hypothesized that most cases of SCAD would not demonstrate true lumen thrombus in the dissected artery, suggesting that anti-platelet agents might not have a role in the treatment of SCAD. Methods: We conducted a systematic review of the published literature through March 2022 to identify pathology images from individuals who died of SCAD. The images were independently reviewed by a pathologist to assess for the presence of thrombus and inflammatory cells. Results: We identified 40 cases from 34 publications with available pathology images and found only one case of true lumen thrombus. Additionally, we found that 53% of cases involved eosinophilic inflammation. Conclusion: The role of antiplatelet agents in the treatment of SCAD should be re-evaluated. Further studies are needed to better understand the significance and treatment implications of eosinophilic inflammation.

12.
Pulmonology ; 28(3): 173-180, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-33500220

RESUMO

BACKGROUND: As delayed intubation may worsen the outcome of coronavirus disease 2019 (COVID-19) patients treated with continuous positive airway pressure (CPAP), we sought to determine COVID-specific early predictors of CPAP failure. METHODS: In this observational retrospective multicentre study, we included all COVID-19 patients treated with out-of-ICU CPAP, candidates for intubation in case of CPAP failure. From these patients, we collected demographic and clinical data. RESULTS: A total of 397 COVID-19 patients were treated with CPAP for respiratory failure, with the therapeutic goal of providing intubation in case of CPAP failure. Univariable analysis showed that, age, lactate dehydrogenase (LDH) and white cell counts were all significantly lower in patients with successful CPAP treatment compared to those failing it and undergoing subsequent intubation. The percentage changes between baseline and CPAP application in the ratio of partial pressure arterial oxygen (PaO2) and fraction of inspired oxygen (FiO2), PaO2, respiratory rate and ROX index were higher in patients experiencing successful CPAP compared to those failing it. FiO2 and male gender were also significantly associated with intubation. Multivariable analysis adjusting for age, gender, Charlson comorbidity index, percentage change in PaO2/FiO2 or PaO2 and FiO2 separately, lactate, white blood cell count, LDH and C-reactive protein levels led to an area under the curve of 0.818 and confirmed that age, LDH and percentage increase in PaO2/FiO2 are predictors of intubation. CONCLUSIONS: In COVID-19 patients requiring CPAP, age, LDH and percentage change in PaO2/FiO2 after starting CPAP are predictors of intubation.


Assuntos
COVID-19 , COVID-19/terapia , Pressão Positiva Contínua nas Vias Aéreas , Humanos , Unidades de Terapia Intensiva , Intubação Intratraqueal , Masculino , Oxigênio/uso terapêutico
13.
J Med Chem ; 65(12): 8227-8244, 2022 06 23.
Artigo em Inglês | MEDLINE | ID: mdl-35675651

RESUMO

We report herein the design, synthesis, and biological investigation of a series of novel Pt(IV) prodrugs with non-steroidal anti-inflammatory drugs naproxen, diclofenac, and flurbiprofen, as well as these with stearic acid in the axial position. Six Pt(IV) prodrugs 5-10 were designed, which showed superior antiproliferative activity compared to cisplatin as well as an ability to overcome tumor cell line resistance to cisplatin. By tuning the drug lipophilicity via variation of the axial ligands, the most potent Pt(IV) prodrug 7 was obtained, with an enhanced cellular accumulation of up to 153-fold that of cisplatin and nanomolar cytotoxicity both in 2D and 3D cell cultures. Pt2+ species were detected at different depths of MCF-7 spheroids after incubation with Pt(IV) prodrugs using a Pt-coated carbon nanoelectrode. Cisplatin accumulation in vivo in the murine mammary EMT6 tumor tissue of BALB/c mice after Pt(IV) prodrug injection was proved electrochemically as well. The drug tolerance study on BALB/c mice showed good tolerance of 7 in doses up to 8 mg/kg.


Assuntos
Anti-Inflamatórios não Esteroides , Antineoplásicos , Compostos de Platina , Pró-Fármacos , Animais , Anti-Inflamatórios não Esteroides/farmacologia , Antineoplásicos/farmacologia , Linhagem Celular Tumoral , Cisplatino/farmacologia , Desenho de Fármacos , Humanos , Células MCF-7 , Camundongos , Camundongos Endogâmicos BALB C , Compostos de Platina/farmacologia , Pró-Fármacos/farmacologia
14.
J Exp Med ; 191(10): 1807-12, 2000 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-10811873

RESUMO

Little is known about innate immunity to bacteria after birth in the hitherto sterile fetal intestine. Breast-feeding has long been associated with a lower incidence of gastrointestinal infections and inflammatory and allergic diseases. We found in human breast milk a 48-kD polypeptide, which we confirmed by mass spectrometry and sequencing to be a soluble form of the bacterial pattern recognition receptor CD14 (sCD14). Milk sCD14 (m-sCD14) concentrations were up to 20-fold higher than serum sCD14 from nonpregnant, pregnant, or lactating women. In contrast, lipopolysaccharide (LPS)-binding protein was at very low levels. Mammary epithelial cells produced 48-kD sCD14. m-sCD14 mediated activation by LPS and whole bacteria of CD14 negative cells, including intestinal epithelial cells, resulting in release of innate immune response molecules. m-sCD14 was undetectable in the infant formulas and commercial (cows') milk tested, although it was present in bovine colostrum. These findings indicate a sentinel role for sCD14 in human milk during bacterial colonization of the gut, and suggest that m-sCD14 may be involved in modulating local innate and adaptive immune responses, thus controlling homeostasis in the neonatal intestine.


Assuntos
Bactérias/imunologia , Receptores de Lipopolissacarídeos/metabolismo , Leite Humano/imunologia , Leite Humano/microbiologia , Sequência de Aminoácidos , Animais , Bovinos , Colostro/imunologia , Feminino , Humanos , Imunidade Inata , Imunidade nas Mucosas , Alimentos Infantis/análise , Recém-Nascido , Intestinos/imunologia , Intestinos/microbiologia , Receptores de Lipopolissacarídeos/sangue , Receptores de Lipopolissacarídeos/genética , Dados de Sequência Molecular , Gravidez , Solubilidade
15.
J Med Chem ; 63(21): 13031-13063, 2020 11 12.
Artigo em Inglês | MEDLINE | ID: mdl-32985193

RESUMO

A series of 73 ligands and 73 of their Cu+2 and Cu+1 copper complexes with different geometries, oxidation states of the metal, and redox activities were synthesized and characterized. The aim of the study was to establish the structure-activity relationship within a series of analogues with different substituents at the N(3) position, which govern the redox potentials of the Cu+2/Cu+1 redox couples, ROS generation ability, and intracellular accumulation. Possible cytotoxicity mechanisms, such as DNA damage, DNA intercalation, telomerase inhibition, and apoptosis induction, have been investigated. ROS formation in MCF-7 cells and three-dimensional (3D) spheroids was proven using the Pt-nanoelectrode. Drug accumulation and ROS formation at 40-60 µm spheroid depths were found to be the key factors for the drug efficacy in the 3D tumor model, governed by the Cu+2/Cu+1 redox potential. A nontoxic in vivo single-dose evaluation for two binuclear mixed-valence Cu+1/Cu+2 redox-active coordination compounds, 72k and 61k, was conducted.


Assuntos
Complexos de Coordenação/química , Cobre/química , Imidazóis/química , Antineoplásicos/química , Antineoplásicos/metabolismo , Antineoplásicos/farmacologia , Apoptose/efeitos dos fármacos , Complexos de Coordenação/metabolismo , Complexos de Coordenação/farmacologia , Cristalografia por Raios X , Dano ao DNA/efeitos dos fármacos , Humanos , Ligantes , Células MCF-7 , Modelos Biológicos , Conformação Molecular , Oxirredução , Espécies Reativas de Oxigênio/metabolismo , Esferoides Celulares/efeitos dos fármacos , Relação Estrutura-Atividade , Telomerase/antagonistas & inibidores , Telomerase/metabolismo
16.
Toxicol Lett ; 287: 70-82, 2018 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-29408348

RESUMO

The cosmetic industry's growing concern about the impact of its supply chain on the environment, sustainability of raw materials, and biodiversity increases the need to ensure that the final product has a lower environmental impact. The objective of this review is to summarize and compare the information available from international organizations and legislation regarding the main criteria used to assess raw materials for aquatic toxicity, as well as the most suitable alternative methods for obtaining assessment parameters. Using the literature available in databases, a review of the scientific literature and international legislation, this work discusses and compares the parameters established by international organizations such as the Environmental Protection Agency (EPA) and Cradle to Cradle (C2C), as well as European legislation, namely, European Regulation 1272/2008, for assessing environmental impact. Defining the ecotoxicity parameters of the main classes of raw materials in rinse-off cosmetic products can enable the development of products that are more environmentally sustainable, prioritizing substances with less environmental impact.


Assuntos
Cosméticos/efeitos adversos , Ecotoxicologia/métodos , Monitoramento Ambiental/métodos , Poluentes Químicos da Água/efeitos adversos , Poluição Química da Água , Qualidade da Água , Animais , Conservação dos Recursos Naturais , Cosméticos/análise , Ecotoxicologia/legislação & jurisprudência , Meio Ambiente , Monitoramento Ambiental/legislação & jurisprudência , Política Ambiental , Humanos , Formulação de Políticas , Medição de Risco , Poluentes Químicos da Água/análise , Poluição Química da Água/legislação & jurisprudência
17.
J Am Coll Cardiol ; 10(4): 743-7, 1987 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-3655142

RESUMO

The relation of degree of regional wall motion abnormality by equilibrium radionuclide angiocardiography to the presence and mural extent of regional necrosis or scar at autopsy was evaluated in 23 autopsy patients who had a history of myocardial infarction and had equilibrium radionuclide angiocardiography within 40 days of death. Of the 228 regions evaluated by equilibrium radionuclide angiocardiography, 135 had abnormal regional wall motion and 102 (76%) of these 135 regions had evidence of myocardial infarction at autopsy. The overall sensitivity, specificity and predictive values of regional wall motion abnormality for regional necrosis or scar were 69, 59 and 76%, respectively. Of the 33 false positive regions, 20 (61%) had severe narrowing of the coronary artery supplying that region, 13 (39%) were adjacent to a region with a myocardial infarction and almost half (16 [48%]) were in the lateral wall. Eighty-three (36%) of the 228 regions were akinetic or dyskinetic, 52 (23%) were hypokinetic and 93 (41%) were normal. Sixty-three (76%) of the 83 akinetic/dyskinetic segments had transmural myocardial infarction at autopsy, 14 (17%) had nontransmural myocardial infarction and only 6 (7%) contained no necrosis or scar. In contrast, 14 (27%) of 52 hypokinetic segments had transmural myocardial infarction, 11 (21%) had nontransmural myocardial infarction and 27 (52%) were normal. Thus, the most severe regional wall motion abnormality (akinesia/dyskinesia) almost always indicates regional myocardial infarction which is usually transmural whereas less severe dysfunction (hypokinesia) is not necessarily associated with regional necrosis or scar. The severity of regional dysfunction must be considered if equilibrium radionuclide angiocardiography is used to evaluate the presence and mural extent of myocardial infarction within a region.


Assuntos
Coração/diagnóstico por imagem , Contração Miocárdica , Infarto do Miocárdio/diagnóstico por imagem , Adulto , Idoso , Idoso de 80 Anos ou mais , Eletrocardiografia , Reações Falso-Positivas , Feminino , Coração/fisiopatologia , Humanos , Masculino , Pessoa de Meia-Idade , Infarto do Miocárdio/patologia , Infarto do Miocárdio/fisiopatologia , Miocárdio/patologia , Angiografia Cintilográfica
18.
Mol Immunol ; 23(6): 619-24, 1986 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-2427939

RESUMO

The relative distribution of 12 antigenic determinants on the surface of the human growth hormone (hGH) molecule has been established. The necessary information was obtained by testing the ability of paired monoclonal antibodies (MAb) to bind simultaneously or not, to 125I-hGH which leads to the formation of 1:2 or 1:1, Ag-Ab complexes, respectively. The results obtained indicate that the epitopes occupy a large percentage of the total hGH molecular surface and revealed the existence of; an antigenic region specific for hGH; at least two independent domains of immunological identity between hGH and human placental lactogen (hPL), one of them also shared by heterologous GH; and other independent areas of partial cross reactivity with hPL. MAb competition experiments in a solid-phase RIA showed the unreliability of this technique for mapping purposes. The distribution of the hGH epitopes suggested in this work is in accord with present views on protein antigenicity and also explains data existing in the literature concerning the behavior of some of the MAb tested here.


Assuntos
Epitopos/análise , Hormônio do Crescimento/imunologia , Anticorpos Monoclonais/classificação , Anticorpos Monoclonais/imunologia , Ligação Competitiva , Cromatografia em Camada Fina , Humanos , Lactogênio Placentário/imunologia , Radioimunoensaio
19.
Mol Immunol ; 28(11): 1183-92, 1991 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-1720501

RESUMO

Three different epitopes of the human IL-6 (IL-6) molecule were recognized by the mAb B-E4 (IgG2b), B-E8 (IgG1) and B-F6 (IgG1). The affinities of these three mAb for IL-6 differ little in several assays but if ranked by affinity they fall into the following order B-E8 greater than B-E4 greater than B-F6. B-E4 and B-E8 mAb, recognizing two different epitopes, are inhibiting mAb in the bioassay with the IL-6 depending cell line B9, however B-E8 has an inhibiting activity higher than B-E4. Both human natural IL-6 (HnIL-6) and human recombinant IL-6 (HrIL-6) were inhibited but not the murine natural IL-6 (MnIL-6). Surprisingly, not only the non-inhibiting mAb (B-F6) recognizes the HrIL-6 fixed to the receptor but also the inhibiting mAb B-E4 and B-E8. This together with the results obtained in a sandwich ELISA where the same mAb was used as both catcher and tracer to detect HrIL-6, it was concluded that dimeric HrIL-6 is able to fix the IL-6 receptor. Competition studies between monomeric HnIL-6 and dimeric HrIL-6 showed that the affinity of the dimeric HrIL-6 for the receptor was higher than that of HnIL-6.


Assuntos
Interleucina-6/metabolismo , Receptores Imunológicos/metabolismo , Proteínas Recombinantes/metabolismo , Animais , Anticorpos Monoclonais , Reações Antígeno-Anticorpo , Ligação Competitiva , Relação Dose-Resposta a Droga , Eletroforese em Gel de Poliacrilamida , Ensaio de Imunoadsorção Enzimática , Epitopos/imunologia , Humanos , Hibridomas , Camundongos , Camundongos Endogâmicos BALB C , Receptores de Interleucina-6
20.
Cardiol Rev ; 23(5): 236-9, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25699981

RESUMO

Tissue-engineered vascular grafts (TEVGs) are currently being developed to overcome the limitations and complications associated with traditional synthetic grafts. This article aims to review the current status of research into the production and use of tissue-engineered grafts. TEVGs have a number of theoretical advantages over synthetic grafts. The results of animal and human studies have been promising, but more work must be done before TEVGs can replace traditional grafts.


Assuntos
Materiais Biocompatíveis , Prótese Vascular , Engenharia Tecidual/métodos , Alicerces Teciduais , Doenças Vasculares/cirurgia , Animais , Implante de Prótese Vascular , Humanos
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