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1.
J Chromatogr A ; 1713: 464569, 2024 Jan 04.
Artigo em Inglês | MEDLINE | ID: mdl-38091845

RESUMO

In steam cracking, upstream pyrolysis oil hydroprocessing, and in many downstream processes, olefinic content is key to assess process performance and process safety risk associated with highly exothermic reactions. When looking to plastic pyrolysis oils as a potential feedstock, as well as downstream products such as pyrolysis gasoline (pygas), these materials contain unsaturated hydrocarbons which are not present in fossil feedstocks. Pygas is a product of pyrolysis and exhibits a large number of chemical structural similarities with plastic pyrolysis oils, especially in terms of olefins structure. Quantification of the unsaturation content (olefins and di-olefins) is extremely important in industry, hence the focus of this manuscript. Detailed hydrocarbon analysis with flame ionization detection is inadequate to fully characterize the hydrocarbon composition of such samples, especially when peaks are closely eluting, or even co-eluting. In this study, the gas chromatography coupled to vacuum ultraviolet (GC-VUV) detection method previously described for the analysis of liquid hydrocarbon streams1 and plastic pyrolysis oils2 has been compared with comprehensive gas chromatography (GC × GC) and the industry standard for olefin quantification (i.e., bromine number titration). Although based on different methodologies, a correlation between the olefin content obtained from GC-VUV and the bromine number titration method is hereby presented.


Assuntos
Alcenos , Gasolina , Gasolina/análise , Alcenos/análise , Bromo , Vácuo , Pirólise , Cromatografia Gasosa/métodos , Óleos/análise , Hidrocarbonetos/análise
2.
J Am Heart Assoc ; 10(1): e018184, 2021 01 05.
Artigo em Inglês | MEDLINE | ID: mdl-33327737

RESUMO

Background Type 2 diabetes mellitus is a risk factor for lower extremity arterial disease. Cilostazol expresses antiplatelet, anti-inflammatory, and vasodilator actions and improves the claudication intermittent symptoms. We investigated the efficacy and safety of adjunctive cilostazol to clopidogrel-treated patients with type 2 diabetes mellitus exhibiting symptomatic lower extremity arterial disease, in the prevention of ischemic vascular events and improvement of the claudication intermittent symptoms. Methods and Results In a prospective 2-arm, multicenter, open-label, phase 4 trial, patients with type 2 diabetes mellitus with intermittent claudication receiving clopidogrel (75 mg/d) for at least 6 months, were randomly assigned in a 1:1 ratio, either to continue to clopidogrel monotherapy, without receiving placebo cilostazol (391 patients), or to additionally receive cilostazol, 100 mg twice/day (403 patients). The median duration of follow-up was 27 months. The primary efficacy end point, the composite of acute ischemic stroke/transient ischemic attack, acute myocardial infarction, and death from vascular causes, was significantly reduced in patients receiving adjunctive cilostazol compared with the clopidogrel monotherapy group (sex-adjusted hazard ratio [HR], 0.468; 95% CI, 0.252-0.870; P=0.016). Adjunctive cilostazol also significantly reduced the stroke/transient ischemic attack events (sex-adjusted HR, 0.38; 95% CI, 0.15-0.98; P=0.046) and improved the ankle-brachial index and pain-free walking distance values (P=0.001 for both comparisons). No significant difference in the bleeding events, as defined by Bleeding Academic Research Consortium criteria, was found between the 2 groups (sex-adjusted HR, 1.080; 95% CI, 0.579-2.015; P=0.809). Conclusions Adjunctive cilostazol to clopidogrel-treated patients with type 2 diabetes mellitus with symptomatic lower extremity arterial disease may lower the risk of ischemic events and improve intermittent claudication symptoms, without increasing the bleeding risk, compared with clopidogrel monotherapy. Registration URL: https://www.clinicaltrials.gov; Unique identifier: NCT02983214.


Assuntos
Isquemia Encefálica , Cilostazol , Clopidogrel , Diabetes Mellitus Tipo 2/complicações , Claudicação Intermitente , Infarto do Miocárdio , Idoso , Isquemia Encefálica/diagnóstico , Isquemia Encefálica/etiologia , Isquemia Encefálica/mortalidade , Isquemia Encefálica/prevenção & controle , Cilostazol/administração & dosagem , Cilostazol/efeitos adversos , Clopidogrel/administração & dosagem , Clopidogrel/efeitos adversos , Monitoramento de Medicamentos/métodos , Quimioterapia Combinada/métodos , Feminino , Humanos , Claudicação Intermitente/complicações , Claudicação Intermitente/terapia , Extremidade Inferior/irrigação sanguínea , Extremidade Inferior/fisiopatologia , Masculino , Infarto do Miocárdio/diagnóstico , Infarto do Miocárdio/etiologia , Infarto do Miocárdio/mortalidade , Infarto do Miocárdio/prevenção & controle , Avaliação de Processos e Resultados em Cuidados de Saúde , Inibidores da Agregação Plaquetária/administração & dosagem , Inibidores da Agregação Plaquetária/efeitos adversos , Resultado do Tratamento
3.
J Chromatogr A ; 1637: 461837, 2021 Jan 25.
Artigo em Inglês | MEDLINE | ID: mdl-33383237

RESUMO

The conversion of waste streams into a useable material through a recycling process is a hot topic. Waste streams can originate from domestic and industrial sources and range from plastic waste to medical waste to various industrial waste streams, both solid and liquid. In addition to waste circularity, circularity for bio-based waste streams and renewable sources are also being investigated. To simplify this complexity, this article presents a case study evaluating the output from the feedstock recycling of plastic waste originating from municipal solid waste. Plastic waste entering the environment is undesired, and many initiatives are working towards a plastics circular economy. Once disposed of, ideally, plastic waste should be either re-used or recycled in order to avoid incineration or disposal in landfills. Recycling waste plastic can occur either via mechanical recycling or feedstock (chemical) recycling, where feedstock recycling can occur for example, through gasification or pyrolysis technologies. This article will focus only on the oils obtained from the pyrolysis of mixed waste plastic. The output from pyrolysis has a different composition than traditional fossil-based hydrocarbon streams, and therefore, must be evaluated to correctly process as feedstock. The authors have previously shown that gas chromatography coupled to vacuum ultraviolet detection (GC-VUV) provides accurate identification and quantification of the hydrocarbon composition (paraffins, isoparaffins, olefins, naphthenes, and aromatics - PIONA) of fossil-based liquid hydrocarbon streams.1 Therefore, GC-VUV was evaluated for analysis of the pyrolysis oils from plastic waste. Using an in-house modified spectral library in combination with the PIONA+ software, accurate identification and quantification of the hydrocarbon composition of pyrolysis oils from C4 through C30+ was possible with a limit of detection of 0.1 wt.%. To the best of our knowledge, this article is the first example of accurate PIONA-type quantification of pyrolysis oils by GC-VUV.


Assuntos
Cromatografia Gasosa/métodos , Óleos/química , Plásticos/química , Pirólise , Resíduos Sólidos/análise , Alcenos/análise , Hidrocarbonetos/análise , Reprodutibilidade dos Testes
4.
J Chromatogr A ; 1587: 239-246, 2019 Feb 22.
Artigo em Inglês | MEDLINE | ID: mdl-30583879

RESUMO

Hydrocarbons analysis is important in the oil and gas industry, as stream composition has a strong impact on plant operations. The composition of hydrocarbon streams vary across a plant, which makes the selection of analytical methods challenging. Traditional methods for the evaluation of liquid hydrocarbon streams include the Detailed Hydrocarbon Analysis (DHA); however, non-traditional methods, such as comprehensive gas chromatography (GCxGC), are also utilized in the chemical industry, including Dow. This work details a comparison of analytical techniques available for such analyses, specifically, DHA and GCxGC compared to the recently introduced GC-Vacuum Ultra Violet (GC-VUV) system. Numerous liquid hydrocarbon streams were blended together to generate a composite and extensive matrix in terms of composition. Paraffin, isoparaffin, olefin, naphthene, and aromatic (PIONA) results are presented for the three techniques. All of those methods obtained relative standard deviations lower than 1.3% for five injections a day for three days. Standard addition curves were utilized to accurately quantify specific compounds in a liquid hydrocarbon stream, and these results were compared to the GC-VUV PIONA+ and DHA quantification procedures.


Assuntos
Cromatografia Gasosa/métodos , Hidrocarbonetos/análise , Raios Ultravioleta , Vácuo , Alcenos/análise , Calibragem , Naftalenos/análise
5.
J Proteomics ; 188: 59-62, 2018 09 30.
Artigo em Inglês | MEDLINE | ID: mdl-29518575

RESUMO

The global incidence of metabolic disorders like type 2 diabetes mellitus (DM2) has assumed epidemic proportions, leading to adverse health and socio-economic impacts. It is therefore of critical importance the early diagnosis of DM2 patients and the detection of those at increased risk of disease. In this respect, Precision Medicine (PM) is an emerging approach that includes practices, tests, decisions and treatments adapted to the characteristics of each patient. With regard to DM2, PM manages a wealth of "omics" data (genomic, metabolic, proteomic, environmental, clinical and paraclinical) to increase the number of clinically validated biomarkers in order to identify patients in early stage even before the prediabetic phase. SIGNIFICANCE: In this paper, we discuss the epidemic dimension of metabolic disorders like type 2 diabetes mellitus (DM2) and the urgent demand for novel biomarkers to reduce the incidence or even delay the onset of DM2. Recent research data produced by "multi-omics" technologies (genomics/epigenomics, transcriptomics, proteomics and metabolomics), suggest that many potential biomarkers might be helpful in the prediction and early diagnosis of DM2. Predictive, Preventive and Personalized Medicine (PPPM) manages and integrates these data to apply personalized, preventive, and therapeutic approaches. This is significant because there is an emerging need for establishing channels for communication and personalized consultation between systems research and precision medicine, as the medicine of the future.


Assuntos
Diabetes Mellitus Tipo 2/diagnóstico , Biomarcadores/análise , Diabetes Mellitus Tipo 2/prevenção & controle , Diabetes Mellitus Tipo 2/terapia , Diagnóstico Precoce , Genômica/métodos , Humanos , Metabolômica/métodos , Proteômica/métodos
6.
EPMA J ; 7: 10, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27182287

RESUMO

Micronutrients are indispensable for a variety of vital functions. Micronutrient deficiencies are a global problem concerning two billion people. In most cases, deficiencies are treatable with supplementation of the elements in lack. Drug-nutrient interactions can also lead to micronutrient reduce or depletion by various pathways. Supplementation of the elements and long-term fortification programs for populations at risk can prevent and restore the related deficiencies. Within the context of Predictive, Preventive, and Personalized Medicine, a multi-professional network should be developed in order to identify, manage, and prevent drug-micronutrient interactions that can potentially result to micronutrient deficiencies.

7.
Public Health Nutr ; 9(4): 449-64, 2006 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-16870017

RESUMO

OBJECTIVE: There is increasing evidence for a significant effect of processed meat (PM) intake on cancer risk. However, refined knowledge on how components of this heterogeneous food group are associated with cancer risk is still missing. Here, actual data on the intake of PM subcategories is given; within a food-based approach we considered preservation methods, cooking methods and nutrient content for stratification, in order to address most of the aetiologically relevant hypotheses. DESIGN AND SETTING: Standardised computerised 24-hour diet recall interviews were collected within the framework of the European Prospective Investigation into Cancer and Nutrition (EPIC), a prospective cohort study in 27 centres across 10 European countries. SUBJECTS: Subjects were 22,924 women and 13,031 men aged 35-74 years. RESULTS: Except for the so-called 'health-conscious' cohort in the UK, energy-adjusted total PM intake ranged between 11.1 and 47.9 g day(-1) in women and 18.8 and 88.5 g day(-1) in men. Ham, salami-type sausages and heated sausages contributed most to the overall PM intake. The intake of cured (addition of nitrate/nitrite) PM was highest in the German, Dutch and northern European EPIC centres, with up to 68.8 g day(-1) in men. The same was true for smoked PM (up to 51.8 g day(-1)). However, due to the different manufacturing practice, the highest average intake of NaNO2 through PM consumption was found for the Spanish centres (5.4 mg day(-1) in men) as compared with German and British centres. Spanish centres also showed the highest intake of NaCl-rich types of PM; most cholesterol- and iron-rich PM was consumed in central and northern European centres. Possibly hazardous cooking methods were more often used for PM preparation in central and northern European centres. CONCLUSIONS: We applied a food-based categorisation of PM that addresses aetiologically relevant mechanisms for cancer development and found distinct differences in dietary intake of these categories of PM across European cohorts. This predisposes EPIC to further investigate the role of PM in cancer aetiology.


Assuntos
Culinária/métodos , Inquéritos sobre Dietas , Manipulação de Alimentos/métodos , Produtos da Carne/efeitos adversos , Neoplasias/epidemiologia , Neoplasias/etiologia , Adulto , Idoso , Animais , Estudos de Coortes , Computadores , Europa (Continente)/epidemiologia , Feminino , Humanos , Masculino , Rememoração Mental , Pessoa de Meia-Idade , Valor Nutritivo , Vigilância da População/métodos , Estudos Prospectivos , Fatores de Risco
8.
Int J Cancer ; 111(5): 762-71, 2004 Sep 20.
Artigo em Inglês | MEDLINE | ID: mdl-15252848

RESUMO

The evidence for anthropometric factors influencing breast cancer risk is accumulating, but uncertainties remain concerning the role of fat distribution and potential effect modifiers. We used data from 73,542 premenopausal and 103,344 postmenopausal women from 9 European countries, taking part in the EPIC study. RRs from Cox regression models were calculated, using measured height, weight, BMI and waist and hip circumferences; categorized by cohort-wide quintiles; and expressed as continuous variables, adjusted for study center, age and other risk factors. During 4.7 years of follow-up, 1,879 incident invasive breast cancers were identified. In postmenopausal women, current HRT modified the body size-breast cancer association. Among nonusers, weight, BMI and hip circumference were positively associated with breast cancer risk (all ptrend < or = 0.002); obese women (BMI > 30) had a 31% excess risk compared to women with BMI < 25. Among HRT users, body measures were inversely but nonsignificantly associated with breast cancer. Excess breast cancer risk with HRT was particularly evident among lean women. Pooled RRs per height increment of 5 cm were 1.05 (95% CI 1.00-1.16) in premenopausal and 1.10 (95% CI 1.05-1.16) in postmenopausal women. Among premenopausal women, hip circumference was the only other measure significantly related to breast cancer (ptrend = 0.03), after accounting for BMI. In postmenopausal women not taking exogenous hormones, general obesity is a significant predictor of breast cancer, while abdominal fat assessed as waist-hip ratio or waist circumference was not related to excess risk when adjusted for BMI. Among premenopausal women, weight and BMI showed nonsignificant inverse associations with breast cancer.


Assuntos
Composição Corporal , Estatura , Índice de Massa Corporal , Neoplasias da Mama/etiologia , Abdome , Tecido Adiposo , Adulto , Idoso , Peso Corporal , Neoplasias da Mama/epidemiologia , Estudos de Coortes , Europa (Continente)/epidemiologia , Feminino , Terapia de Reposição Hormonal , Humanos , Incidência , Pessoa de Meia-Idade , Estado Nutricional , Obesidade/complicações , Pós-Menopausa , Pré-Menopausa , Estudos Prospectivos , Fatores de Risco
9.
J Cancer Educ ; 17(1): 19-23, 2002.
Artigo em Inglês | MEDLINE | ID: mdl-12000100

RESUMO

BACKGROUND: General practitioners need to play a more active role in the management of patients with breast cancer, specifically in screening programs, counseling, follow-up, palliative care, and psychosocial support. Special training is needed to meet these demands. METHODS: An interactive training program resident on CD-ROM was developed. It includes nine cases designed according to the case method and three cases created for group discussions. The program also contains a self-test and an encyclopedia with facts and figures about breast cancer. The program was tested by 20 trainers/trainees in each of four participating countries. RESULTS: The formata, content, and usefulness of the program were ranked highly: generally between 4 and 5 on a scale from 1 (low) to 5 (high), based on 78 evaluation forms. CONCLUSION: The program seems to be an adequate tool for GP training.


Assuntos
Neoplasias da Mama/terapia , Instrução por Computador , Medicina de Família e Comunidade/educação , Adulto , CD-ROM , Europa (Continente) , Humanos , Pessoa de Meia-Idade , Avaliação de Programas e Projetos de Saúde
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