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1.
Mikrochim Acta ; 191(3): 169, 2024 Feb 29.
Artigo em Inglês | MEDLINE | ID: mdl-38421458

RESUMO

The present work delves into the feasibility of employing a novel structured sorbent referred to as GFAD (Guefoam Adsorption Device) for the determination of volatile organic compounds (VOCs) in liquid samples. The chosen method has been static headspace sorptive extraction-thermal desorption gas chromatography mass spectrometry (HSSE-TD-GC-MS). The GFAD comprises an aluminum cellular material with a distinct replication structure and a solid guest phase consisting of activated carbon particles dispersed within the cavities of the cellular aluminum. The extensive specific surface area, robustness, and exceptional thermal conductivity of this pioneering material offer distinct advantages over commercially available polydimethylsiloxane-based Twister® devices. Therefore, the trapping efficiency for volatile organic compounds is enhanced, and it is possible to perform the analysis of concentrated samples. According to computational simulations, it has been demonstrated that GFAD has a high heat conductivity. As a result, the desorption efficiency is improved, and minimal temperature gradients are generated throughout the GFAD during the heating process. Besides, the energy consumption is significantly lowered, thus aligning with environmentally conscientious and sustainable analytical practices.The experimental results give a proof of the suitability of the GFAD for determining gaseous compounds in liquid samples through HSSE-TD-GC-MS. For volatile species, the new material provides higher peak areas and lower limits of detection than a commercially available Twister® device. Furthermore, the GFAD is reusable, its adsorbing properties remaining unchanged during, at least, 100 consecutive analyses. In addition, unlike to the Twister®, no intense siloxane peaks are observed in the chromatograms obtained with the GFAD. The feasibility of qualitative and semi-quantitative analysis with the new accessory has been demonstrated with both standards and a cereal bioethanol real sample.

2.
Molecules ; 25(13)2020 Jun 27.
Artigo em Inglês | MEDLINE | ID: mdl-32605125

RESUMO

In the present work, 38 elements were quantified in the different fractions generated by applying amateur winemaking methods. Inductively Coupled Plasma Mass Spectrometry was used as detection technique. Grapes were analyzed and separate metal profiles were also obtained for the skin and seeds. Additional vinification fractions included musts before and after the fermentation process. Meanwhile, solid fractions corresponded to the so-called hat, pressed pomace and the lees obtained after gravitational settling at the tank bottom. Wine was further analyzed. The obtained results revealed a different repartition depending on the particular element and winemaking solid and liquid fraction evaluated. The studies included vinification in presence and in absence of added yeast and grape geographical origin. Principal component analysis helped to discriminate among fractions and to determine the critical elements behaving differently. Finally, a mass balance allowed to unequivocally detect the migration of a given element to the winemaking fractions.


Assuntos
Frutas/química , Vitis/química , Vinho/análise , Bebidas Alcoólicas/análise , Fermentação , Humanos , Metais/química , Sementes/química
3.
Molecules ; 25(23)2020 Nov 28.
Artigo em Inglês | MEDLINE | ID: mdl-33260573

RESUMO

This paper presents a novel tool for Spanish commercial wine discrimination according to their designation of origin (PDO). A total of 65 commercial wines from different Spanish designation of origin (Alicante, Bullas, Campo de Borja, Jumilla, Castilla la Mancha, Ribeiro, Ribera de Duero, Rioja, Rueda, Utiel-Requena, Valdepeñas and Valencia) were characterized. The rare earth elements (REEs) content was determined by a high-temperature torch integrated sample introduction system (hTISIS) coupled to inductively coupled plasma mass spectrometry (ICP-MS). The REE content was used to draw characteristic PDOs radar charts. Results indicated that the REEs fingerprint provides a good prospect to discriminate the different Spanish PDOs, except for Alicante, Castilla la Mancha, Jumilla, Utiel-Requena and Valdepeñas. Finally, for those PDOs that were not properly distinguished, a second fingerprint obtained from Ba, Co, Cr, Mn, Ni, Pb and V content was used for discrimination purposes.


Assuntos
Metais Terras Raras/análise , Metais/análise , Vinho/análise , Análise Discriminante , Geografia , Espanha
4.
Anal Chem ; 89(24): 13618-13625, 2017 12 19.
Artigo em Inglês | MEDLINE | ID: mdl-29140072

RESUMO

A novel extraction method was developed, optimized, and validated for the elemental analysis of organic samples. The method, called aerosol-phase extraction (APE), is based on nebulization of the extracting aqueous solution (0.1 mol·L-1 nitric acid) on the sample. Extraction was performed at the interface of generated extractant droplets as they entered into contact with the samples. Afterward, the phases were allowed to separate and Ca, K, Na, and Mg were determined in aqueous phase by means of inductively coupled plasma optical emission spectroscopy (ICP-OES). Measurement of aerosol characteristics demonstrated that a water-in-oil emulsion was generated. Therefore, once the aqueous solution was dispersed into the sample, the phases spontaneously separated. Furthermore, the interfacial specific surface area exhibited values on the order of 1 m2·mL-1, hence enhancing the extraction kinetics over conventional extraction methods. Key variables affecting the extraction yield were the nebulization gas flow rate, liquid flow rate, extraction time, acid concentration, nebulizer tip to sample surface gap, and morg/maq ratio. Once the optimal conditions were selected, the method was applied and validated for the determination of Ca, K, Na, and Mg by ICP-OES in 0.5 mL biodiesel samples with an expanded uncertainty lower than 2%. With the APE method, the extraction time was around 1 min, whereas conventional methods employed to perform this kind of extraction required from 4 to 50 min. Additionally, the APE involved preconcentration of analytes, thus lowering the limit of detection (LOD) to the nanograms per milliliter level (i.e., LODs based on the 3sb criterion were 32, 20, 19, and 24 ng·mL-1 for Ca, K, Na, and Mg, respectively). Furthermore, accuracy of quantification of Ca, K, Na, and Mg concentration by APE was not significantly different as compared to that afforded by conventional liquid-liquid extraction. Finally, Ca, K, Na, and Mg contents were determined in four real samples in the 0.5-13 mg·kg-1 range. The obtained results were not statistically different from those encountered with a microwave-based digestion method.

5.
Anal Chem ; 89(6): 3787-3794, 2017 03 21.
Artigo em Inglês | MEDLINE | ID: mdl-28230344

RESUMO

A proof of concept study involving the online coupling of automatic dispersive liquid-liquid microextraction (DLLME) to inductively coupled plasma optical emission spectrometry (ICP OES) with direct introduction and analysis of the organic extract is herein reported for the first time. The flow-based analyzer features a lab-in-syringe (LIS) setup with an integrated stirring system, a Meinhard nebulizer in combination with a heated single-pass spray chamber, and a rotary injection valve, used as an online interface between the microextraction system and the detection instrument. Air-segmented flow was used for delivery of a fraction of the nonwater miscible extraction phase, 12 µL of xylene, to the nebulizer. All sample preparative steps including magnetic stirring assisted DLLME were carried out inside the syringe void volume as a size-adaptable yet sealed mixing and extraction chamber. Determination of trace level concentrations of cadmium, copper, lead, and silver as model analytes has been demonstrated by microextraction as diethyldithiophosphate (DDTP) complexes. The automatic LIS-DLLME method features quantitative metal extraction, even in troublesome sample matrixes, such as seawater, salt, and fruit juices, with relative recoveries within the range of 94-103%, 93-100%, and 92-99%, respectively. Furthermore, no statistically significant differences at the 0.05 significance level were found between concentration values experimentally obtained and the certified values of two serum standard reference materials.

6.
J Sep Sci ; 38(7): 1073-81, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25641918

RESUMO

In this manuscript, a study of the effect of microwave radiation on the high-performance liquid chromatography separation of tocopherols and vitamin K1 was conducted. The novelty of the application was the use of a relatively low polarity mobile phase in which the dielectric heating effect was minimized to evaluate the nonthermal effect of the microwave radiation over the separation process. Results obtained show that microwave-assisted high-performance liquid chromatography had a shorter analysis time from 31.5 to 13.3 min when the lowest microwave power was used. Moreover, narrower peaks were obtained; hence the separation was more efficient maintaining or even increasing the resolution between the peaks. This result confirms that the increase in mobile phase temperature is not the only variable for improving the separation process but also other nonthermal processes must intervene. Fluorescence detection demonstrated better signal-to-noise compared to photodiode arrayed detection mainly due to the independent effect of microwave pulses on the baseline noise, but photodiode array detection was finally chosen as it allowed a simultaneous detection of nonfluorescent compounds. Finally, a determination of the content of the vitamin E homologs was carried out in different vegetable oils. Results were coherent with those found in the literature.


Assuntos
Cromatografia Líquida de Alta Pressão/métodos , Gorduras/química , Micro-Ondas , Óleos de Plantas/química , Vitaminas/análise , Limite de Detecção , Reprodutibilidade dos Testes , Solubilidade , Vitaminas/química
7.
ACS Omega ; 9(27): 29422-29430, 2024 Jul 09.
Artigo em Inglês | MEDLINE | ID: mdl-39005828

RESUMO

The dispersive liquid-liquid aerosol phase extraction (DLLAPE) method was applied for the determination of Ag, Cd, Cu, Ni, and Pb in seawater samples by inductively coupled plasma optical emission spectroscopy (ICP-OES). Key parameters such as sample pH and extractant concentration were systematically evaluated, with ammonium O,O'-diethyldithiophosphate (DDTP) identified as the optimal chelating agent. Optimal extraction conditions were achieved at pH 2.5 for Ag, Cu, Ni, and Pb, while Cd extraction efficiency was found to be pH independent. The extractant concentration did not greatly improve the extraction efficiency. Furthermore, the influence of nebulizer gas flow rate and extraction time was evaluated, achieving the maximum extraction yield at 0.6 L min-1 and 120 s, respectively. The method was evaluated for accuracy and bias through recovery studies, and the results showed that most elements had recovery rates close to 100% with relative standard deviation values in between 3 and 9%. However, in the case of Ag and Ni, 1.184 and 1.089 correction factors were, respectively, applied to compensate for the bias. Moreover, the procedural limits of quantification (pLOQs) found for Ag, Cd, Cu, Ni, and Pb were 0.4, 0.14, 0.2, 0.2, and 0.2 µg L-1, respectively. The in-house validation of the method provided expanded uncertainty values lower than 6% for all elements except for Ag (16.6%). Finally, the application of the method to real seawater samples from coastal areas in Alicante and San Juan (Spain) confirmed its suitability for trace metal analysis in complex marine matrices, underscoring its potential for environmental monitoring and research.

8.
Appl Spectrosc ; : 37028241263567, 2024 Jun 16.
Artigo em Inglês | MEDLINE | ID: mdl-38881037

RESUMO

The almost-two-centuries history of spectrochemical analysis has generated a body of literature so vast that it has become nearly intractable for experts, much less for those wishing to enter the field. Authoritative, focused reviews help to address this problem but become so granular that the overall directions of the field are lost. This broader perspective can be provided partially by general overviews but then the thinking, experimental details, theoretical underpinnings and instrumental innovations of the original work must be sacrificed. In the present compilation, this dilemma is overcome by assembling the most impactful publications in the area of analytical atomic spectrometry. Each entry was proposed by at least one current expert in the field and supported by a narrative that justifies its inclusion. The entries were then assembled into a coherent sequence and returned to contributors for a round-robin review.

9.
Anal Chim Acta ; 1249: 340948, 2023 Apr 08.
Artigo em Inglês | MEDLINE | ID: mdl-36868775

RESUMO

The high temperature torch integrated sample introduction system (hTISIS) is coupled to microwave plasma optical emission spectrometry (MIP-OES) for the first time. The goal of this work is to develop an accurate analysis of digested samples under continuous sample aspiration mode by coupling the hTISIS to a MIP-OES instrument. To achieve this, different operating conditions such as, nebulization flow rate, liquid flow rate and the spray chamber temperature were optimized in terms of sensitivity, limits of quantification (LOQs) and background equivalent concentration (BECs) for the determination of Ca, Cr, Cu Fe, K, Mg, Mn, Na, Pb and Zn, and these values were compared with those reported with a conventional sample introduction system. Under optimum conditions (0.8-1 L min-1, 100 µL min-1 and 400 ᵒC, respectively), the hTISIS improved MIP-OES analytical figures of merit and shortened 4-times wash out times with respect to a conventional cyclonic spray chamber, reporting an enhancement factor in the sensitivity among 2-47 times and LOQs from 0.9 to 360 µg kg-1. Once the best operating conditions were set, the magnitude of the interference caused by 15 different acid matrices (2, 5 and 10% w/w of HNO3, H2SO4, HCl and mixtures of HNO3 with H2SO4 and HNO3 with HCl) was significantly lower for the former device. Finally, 6 different digested oily samples (used cooking oil, animal fat, corn oil and the same samples after a filtration step) were analyzed by means of an external calibration approach based on the use of multielemental standards prepared in 3% (w/w) HCl solution. The obtained results were compared against those supplied by a conventional methodology employing an inductively coupled plasma optical emission spectrometry, ICP-OES, instrument. It was clearly concluded that the hTISIS coupled to MIP-OES afforded similar concentrations as compared to the conventional methodology.

10.
J Agric Food Chem ; 71(28): 10742-10750, 2023 Jul 19.
Artigo em Inglês | MEDLINE | ID: mdl-37399284

RESUMO

Seventeen extra virgin olive oil samples from Valencian Community (Spain) were submitted to a domestic-frying process (180 °C) during different degradation times (5, 10, 30, 60, 120 min). A dispersive liquid-liquid aerosol phase extraction by using a methanol/water (50:50) extracting solution was used to isolate the polyphenol fraction. Total phenolic content (TPC) was determined, whereas the determination of seven individual target polyphenolic compounds (hydroxytyrosol, tyrosol, oleuropein, vanillic acid, p-coumaric acid, ferulic acid, and vanillin) was carried out by using ultrahigh-performance liquid chromatography coupled to a tandem mass spectrometer. Statistically significant differences in the TPC values were found for Blanqueta and Manzanilla samples from different harvesting years. The domestic-frying process impacted the TPC and the individual phenolic compounds content. Thermal treatment for 2 h gave rise to a 94% decrease in the TPC. A first-order kinetic model was suitable to accurately describe the degradation of the individual phenolic compounds.


Assuntos
Fenóis , Óleos de Plantas , Azeite de Oliva/química , Óleos de Plantas/química , Cromatografia Líquida de Alta Pressão/métodos , Fenóis/análise , Aerossóis
11.
JAMA Netw Open ; 6(4): e237243, 2023 04 03.
Artigo em Inglês | MEDLINE | ID: mdl-37027155

RESUMO

Importance: COVID-19 pneumonia is often associated with hyperinflammation. The efficacy and safety of anakinra in treating patients with severe COVID-19 pneumonia and hyperinflammation are still unclear. Objective: To assess the efficacy and safety of anakinra vs standard of care alone for patients with severe COVID-19 pneumonia and hyperinflammation. Design, Setting, and Participants: The Clinical Trial of the Use of Anakinra in Cytokine Storm Syndrome Secondary to COVID-19 (ANA-COVID-GEAS) was a multicenter, randomized, open-label, 2-group, phase 2/3 clinical trial conducted at 12 hospitals in Spain between May 8, 2020, and March 1, 2021, with a follow-up of 1 month. Participants were adult patients with severe COVID-19 pneumonia and hyperinflammation. Hyperinflammation was defined as interleukin-6 greater than 40 pg/mL, ferritin greater than 500 ng/mL, C-reactive protein greater than 3 mg/dL (rationale, ≥5 upper normal limit), and/or lactate dehydrogenase greater than 300 U/L. Severe pneumonia was considered if at least 1 of the following conditions was met: ambient air oxygen saturation 94% or less measured with a pulse oximeter, ratio of partial pressure O2 to fraction of inspired O2 of 300 or less, and/or a ratio of O2 saturation measured with pulse oximeter to fraction of inspired O2 of 350 or less. Data analysis was performed from April to October 2021. Interventions: Usual standard of care plus anakinra (anakinra group) or usual standard of care alone (SoC group). Anakinra was given at a dose of 100 mg 4 times a day intravenously. Main Outcomes and Measures: The primary outcome was the proportion of patients not requiring mechanical ventilation up to 15 days after treatment initiation, assessed on an intention-to-treat basis. Results: A total of 179 patients (123 men [69.9%]; mean [SD] age, 60.5 [11.5] years) were randomly assigned to the anakinra group (92 patients) or to the SoC group (87 patients). The proportion of patients not requiring mechanical ventilation up to day 15 was not significantly different between groups (64 of 83 patients [77.1%] in the anakinra group vs 67 of 78 patients [85.9%] in the SoC group; risk ratio [RR], 0.90; 95% CI, 0.77-1.04; P = .16). Anakinra did not result in any difference in time to mechanical ventilation (hazard ratio, 1.72; 95% CI, 0.82-3.62; P = .14). There was no significant difference between groups in the proportion of patients not requiring invasive mechanical ventilation up to day 15 (RR, 0.99; 95% CI, 0.88-1.11; P > .99). Conclusions and Relevance: In this randomized clinical trial, anakinra did not prevent the need for mechanical ventilation or reduce mortality risk compared with standard of care alone among hospitalized patients with severe COVID-19 pneumonia. Trial Registration: ClinicalTrials.gov Identifier: NCT04443881.


Assuntos
COVID-19 , Adulto , Masculino , Humanos , Pessoa de Meia-Idade , Proteína Antagonista do Receptor de Interleucina 1/uso terapêutico , SARS-CoV-2 , Padrão de Cuidado , Respiração Artificial
12.
Analyst ; 137(9): 2260-6, 2012 May 07.
Artigo em Inglês | MEDLINE | ID: mdl-22448390

RESUMO

The present work describes the first attempt to use microwave reversed phase high performance liquid chromatography (MW-HPLC) to carry out the separation of organic compounds. Biotin and riboflavin were selected for the characterization of the new separation technique. Additional vitamins (nicotinamide, pyridoxine and thiamine) were used as reference compounds. In order to perform the separation, a chromatographic column was placed inside a domestic microwave oven in a hanging position. The column particular location was an extremely critical point, since it precluded the actual power absorbed by the sample. In order to avoid magnetron damage, a heat well (i.e., water vessels) was used. Vitamins were detected using a UV-VIS detector. Results obtained showed that the application of microwave radiation, even at low power levels, gave rise to a significant modification in the characteristics of the chromatograms. It was found that retention times for biotin and riboflavin shortened as the power increased. Furthermore, the peak shape also changed, with the modification being more significant for the former vitamin than for the latter one. Furthermore, sensitivity also increased as the column was exposed to the action of microwave. Comparatively speaking, MW-HPLC was more efficient in terms of compound separation than when performed at room temperature or thermostatted at 45 °C HPLC. This was likely due to the combined action of a moderate and quick heating of the mobile phase with an increase in the analytes diffusivity caused by the radiation.


Assuntos
Cromatografia Líquida de Alta Pressão/métodos , Micro-Ondas , Espectrofotometria Ultravioleta/métodos , Vitaminas/análise , Vitaminas/isolamento & purificação , Absorção , Temperatura
13.
J Sep Sci ; 35(8): 929-36, 2012 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-22589153

RESUMO

In the present work, an evaporative light scattering detector was used as a high-temperature liquid chromatography detector for the determination of carbohydrates. The compounds studied were glucose, fructose, galactose, sucrose, maltose, and lactose. The effect of column temperature on the retention times and detectability of these compounds was investigated. Column heating temperatures ranged from 25 to 175°C. The optimum temperature in terms of peak resolution and detectability with pure water as mobile phase and a liquid flow rate of 1 mL/min was 150°C as it allowed the separation of glucose and the three disaccharides here considered in less than 3 min. These conditions were employed for lactose determination in milk samples. Limits of quantification were between 2 and 4.7 mg/L. On the other hand, a temperature gradient was developed for the simultaneous determination of glucose, fructose, and sucrose in orange juices, due to coelution of monosaccharides at temperatures higher than 70°C, being limits of quantifications between 8.5 and 12 mg/L. The proposed hyphenation was successfully applied to different types of milk and different varieties of oranges and mandarins. Recoveries for spiked samples were close to 100% for all the studied analytes.


Assuntos
Bebidas/análise , Cromatografia Líquida de Alta Pressão/métodos , Dissacaridases/análise , Leite/química , Monossacarídeos/análise , Animais , Bovinos , Cromatografia Líquida de Alta Pressão/instrumentação , Espalhamento de Radiação , Sensibilidade e Especificidade , Temperatura
14.
Polymers (Basel) ; 13(3)2021 Jan 22.
Artigo em Inglês | MEDLINE | ID: mdl-33499051

RESUMO

The present work shows, for the first time, the application of laser ablation connected to inductively coupled plasma mass spectrometry (LA-ICP-MS) to the localized quantitative analysis of inclusions in polymeric industrial films. The multielemental mapping capabilities of LA-ICP-MS has allowed to chemically examine unique defects appeared during the plastic processing. This analytical tool is perfectly suited to detect elements such as Al, Mg, Zr, Ti, Cr, P, Pb, Sb, Zn, and Si in those inclusions. A method for multielemental quantitative analysis of these defects has been developed in the present work. The profiling for more than 100 different defects in three samples has demonstrated that more than 50% of these inclusions contain aggregates of some of the aforementioned elements. Therefore, the distribution of elements used as additives or present in catalysts must be carefully controlled during the production of polymeric films in order to avoid degradation in their performance.

15.
Anal Chim Acta ; 1094: 34-46, 2020 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-31761046

RESUMO

This report presents a study on the determination of total polyphenols together with metals in several samples of olive oil produced in Spain. The results provided by applying a conventional extraction method were compared against those encountered by means of the so-called Dispersive Liquid-Liquid Aerosol Phase Extraction method. The novel method is based on the dispersion of the extracting solution in the sample. To accomplish this, an aerosol is pneumatically generated and directed against the surface of the oil sample. The aerosol was generated in order to increase as much as possible the surface area of the interface between the two involved non-miscible phases. As a result, the partition equilibrium was quickly achieved. The critical variables dictating the characteristics of the obtained aerosols as well as those influencing the partition equilibrium state were studied. With the aerosol phase extraction method, the values corresponding to the total polyphenols and metals in real samples were not statistically different as compared to those obtained by the conventional liquid - liquid extraction method. The new method provided shorter extraction times and lower mass of consumed reagents than the conventional one, thus giving rise to a more environmentally friendly method. For polyphenols, calculated limits of detection and quantification were 0.48 and 1.5 mg of gallic acid kg-1, respectively. The absorbance linearity, in turn, was kept from 0 to 50 mg kg-1 (R2 = 0.998). In the case of metal and metalloid quantification, the limits of detection found with a sample digestion method ranged from 1.3 (Cu) to 291 (Na) ng mL-1. Meanwhile, because of the lower dilution factor, this parameter was one order of magnitude lower when these elements were extracted according to the new method. The new extraction method was applied to the analysis of 42 extra virgin olive oils both bottled and directly collected from the oil press, containing single cultivars or blends and produced from different areas. Fresh oils were analyzed and a preliminary study on the oil thermal degradation was also done. Dispersing the extracting solution as an aerosol into the sample can be considered a versatile method able to provide extensive oil chemical information in a rapid way what is especially important in the case of polyphenols.


Assuntos
Extração Líquido-Líquido/métodos , Espectrometria de Massas/métodos , Metais/análise , Azeite de Oliva/análise , Polifenóis/análise , Aerossóis/química , Limite de Detecção , Espanha
16.
ACS Omega ; 5(33): 20912-20921, 2020 Aug 25.
Artigo em Inglês | MEDLINE | ID: mdl-32875226

RESUMO

Forty-one bioethanol real samples and related fractions, together with a biobutanol sample, have been analyzed with gas chromatography coupled to either mass spectrometry (GC-MS) or flame ionization detection (GC-FID). Bioethanol with different water contents, samples originated from several sources of biomass, first- as well as second-generation specimens, distillation fractions, samples stocked in containers made of four different materials, and, finally, a biobutanol sample have been analyzed. The number of the compounds found through GC-MS has been 130, including alcohols, aldehydes, ketones, esters, ethers, nitrogen compounds, organic acids, furane derivates as well as other species (e.g., limonene). Afterward, a quantitative determination of major components of bioethanol has been carried out. The achieved results have revealed that, besides ethanol and, in some cases, water, species such as acetaldehyde, methanol, and higher alcohols, as well as 1,1-diethoxyethane, may be present at concentrations above 500 mg L-1. While the source of bioethanol (nature of the raw material, ethanol generation, or water content) has a direct impact on its volatile organic compound (VOC) profile, the material of the container where the biofuel has been stored does not play a significant role. Finally, the results have demonstrated that, for a given production process, different distillation fractions contain unequal VOC profiles.

17.
Thromb Res ; 123 Suppl 2: S10-5, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-19217463

RESUMO

BACKGROUND: Cancer patients with venous thromboembolism (VTE) have an increased incidence of recurrences and bleeding complications Reliable information on the factors determining the risk for such complications may facilitate better use of therapy. METHODS: RIETE Registry is an ongoing, international registry of consecutive patients presenting with symptomatic acute VTE confirmed by objective tests. We assessed the 3-month outcome in all women with active cancer, trying to identify if differences exist according to the tumor site. RESULTS: Up to May 2007, 18,883 patients had been enrolled. Of them, 3805 (20%) had active cancer, 1719 (45%) were women. During the 3-month study period, 40 (2.3%) had recurrent deep vein thrombosis, 39 (2.3%) recurrent pulmonary embolism (PE), 67 (3.9%) major bleeding, 394 (23%) died. Of these, 13 (33%) women with recurrent PE died of the PE, 17 (42%) with major bleeding had fatal bleeding. In women with gastrointestinal (5.7% vs. 4.3%) or genitourinary (6.4% vs. 4.7%) cancers the incidence of bleeding complications exceeded that of VTE recurrences, while in those with brain (3.4% vs. 13%) or lung cancer (2.6% vs. 11%) the rate of recurrences outweighed that of major bleeding. CONCLUSIONS: We identified significant differences in outcome according to the site of cancer that may help to identify those women with cancer and VTE at a higher risk for recurrences or major bleeding.


Assuntos
Hemorragia/etiologia , Recidiva Local de Neoplasia/sangue , Neoplasias/sangue , Tromboembolia Venosa/complicações , Idoso , Anticoagulantes/uso terapêutico , Feminino , Humanos , Neoplasias/terapia , Estudos Prospectivos , Embolia Pulmonar/complicações , Embolia Pulmonar/diagnóstico , Sistema de Registros , Fatores de Risco , Resultado do Tratamento , Tromboembolia Venosa/sangue , Tromboembolia Venosa/diagnóstico , Trombose Venosa/complicações , Trombose Venosa/diagnóstico
18.
Clin Hemorheol Microcirc ; 42(1): 65-9, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-19363241

RESUMO

It is not yet known whether Yasmin involves a higher thrombotic risk compared with other contraceptives. We present a serie of eight new cases of women who developed thrombotic events early after starting on Yasmin who were sent to our Thrombosis and Hemostasis Unit for a thrombophilia work-up in the last five years. Only two of them were heterozygous carriers of the prothrombin G20210A mutation and three were obese while none of them were smoker. These new cases provide information about the characteristics of the thrombotic events and the concomitant risk factors, indicating that this pill may not be as safe as had been previously thought, and suggest that new studies regarding safety profile of Yasmin are required to explain the association with venous thrombotic events.


Assuntos
Androstenos/efeitos adversos , Anticoncepcionais Orais Combinados/efeitos adversos , Etinilestradiol/efeitos adversos , Tromboembolia Venosa/induzido quimicamente , Adulto , Feminino , Predisposição Genética para Doença , Humanos , Protrombina/genética , Fatores de Risco , Adulto Jovem
19.
Br J Haematol ; 141(5): 716-9, 2008 May.
Artigo em Inglês | MEDLINE | ID: mdl-18341631

RESUMO

This study aimed to assess the fibrinolytic inhibitors and their association with thrombosis in Behçet disease. Thrombin activatable fibrinolysis inhibitor (TAFI) (P < 0.001) and plasminogen activator inhibitor-1 (PAI-1) levels (P = 0.022) were significantly higher in 79 patients than in 84 controls. No significant differences were observed in CPB2 (TAFI) Thr325Ile and SERPINE1 (PAI1) 4G/5G polymorphism distribution between patients and controls. TAFI activity levels were significantly higher in patients with thrombosis than in those without thrombosis (P = 0.024). In conclusion, the increased TAFI levels in Behçet disease could contribute to the increased risk of thrombosis observed in these patients.


Assuntos
Síndrome de Behçet/sangue , Carboxipeptidase B2/sangue , Inibidor 1 de Ativador de Plasminogênio/sangue , Polimorfismo Genético , Trombose/sangue , Adulto , Síndrome de Behçet/genética , Glicemia/análise , Feminino , Fibrinólise , Predisposição Genética para Doença , Humanos , Lipídeos/sangue , Masculino , Pessoa de Meia-Idade , Trombose/genética
20.
Thromb Haemost ; 100(1): 26-31, 2008 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-18612534

RESUMO

A score that can accurately determine the risk of major bleeding during anticoagulant therapy may help to make decisions on anticoagulant use. RIETE is an ongoing registry of consecutive patients with acute venous thromboembolism (VTE). We composed a score to predict the risk for major bleeding within three months of anticoagulant therapy. Of 19,274 patients enrolled, 13,057 (67%) were randomly assigned to the derivation sample, 6,572 to the validation sample. In the derivation sample 314 (2.4%) patients bled (fatal bleeding, 105). On multivariate analysis, age >75 years, recent bleeding, cancer, creatinine levels >1.2 mg/dl, anemia, or pulmonary embolism at baseline were independently associated with an increased risk for major bleeding. A score was composed assigning 2 points to recent bleeding, 1.5 to abnormal creatinine levels or anemia, 1 point to the remaining variables. In the derivation sample 2,654 (20%) patients scored 0 points (low risk); 9,645 (74%) 1-4 points (intermediate); 758 (5.8%) >4 points (high risk). The incidences of major bleeding were: 0.3% (95% confidence interval [CI]: 0.1-0.6), 2.6% (95% CI: 2.3-2.9), and 7.3% (95% CI: 5.6-9.3), respectively. The likelihood ratio test was: 0.14 (95% CI: 0.07-0.27) for patients at low risk;2.96 (95% CI: 2.18-4.02) for those at high risk. In the validation sample the incidence of major bleeding was: 0.1%, 2.8%, and 6.2%, respectively. In conclusion, a risk score based on six variables documented at entry can identify VTE patients at low, intermediate, or high risk for major bleeding during the first three months of therapy.


Assuntos
Anticoagulantes/efeitos adversos , Hemorragia/induzido quimicamente , Tromboembolia Venosa/tratamento farmacológico , Doença Aguda , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Anemia/complicações , Argentina/epidemiologia , Creatinina/sangue , Europa (Continente)/epidemiologia , Feminino , Hemorragia/sangue , Hemorragia/epidemiologia , Humanos , Incidência , Israel/epidemiologia , Funções Verossimilhança , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Seleção de Pacientes , Estudos Prospectivos , Embolia Pulmonar/complicações , Sistema de Registros , Reprodutibilidade dos Testes , Medição de Risco , Fatores de Risco , Fatores de Tempo , Resultado do Tratamento , Tromboembolia Venosa/sangue , Tromboembolia Venosa/epidemiologia
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