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1.
Patient Educ Couns ; 102(3): 511-519, 2019 03.
Article in English | MEDLINE | ID: mdl-30279028

ABSTRACT

The objective of this study was to assess the effectiveness of an education program and telephone call follow-up at improving the health related quality of life (HRQL) of patients with chronic obstructive pulmonary disease (COPD). METHOD: Experimental, controlled, randomized, single blind study, masked data analysis. Duration of 2 years and 3 months. Patients hospitalised for exacerbation. The effectiveness was evaluated by calculating the absolute and relative change (%) of the St. George questionnaire scores (total and by dimensions) before and after the intervention program. Calculation of the effect of the group variable on the absolute and relative changes of the variables, Multiple Analysis of Variance (MANOVA). RESULTS: Completed study of 116 patients. Greater effects on their HRQL reported at admission (48.3 ± SD 20.0 years). Patients in the intervention group improved significantly in their total SGRQ scores (-6.83) in absolute and relative terms and more significantly in their activity dimension (-16.05). CONCLUSIONS: The education program was effective at improving global HRQL, especially the activity dimension, in exacerbated COPD patients. PRACTICE IMPLICATIONS: This research contributes to clarifying the benefits and contents of education programs for patients with COPD; hospital admission is the suitable moment to contact these patients.


Subject(s)
Inpatients/education , Patient Education as Topic/methods , Pulmonary Disease, Chronic Obstructive/psychology , Quality of Life , Aged , Aged, 80 and over , Female , Follow-Up Studies , Hospitalization , Humans , Inpatients/psychology , Male , Middle Aged , Outcome Assessment, Health Care , Pulmonary Disease, Chronic Obstructive/physiopathology , Single-Blind Method , Spain , Surveys and Questionnaires , Telephone
2.
Insect Sci ; 25(4): 631-642, 2018 Aug.
Article in English | MEDLINE | ID: mdl-28213963

ABSTRACT

Resistance of the melon line TGR-1551 to the aphid Aphis gossypii is based on preventing aphids from ingesting phloem sap. In electrical penetration graphs (EPGs), this resistance has been characterized with A. gossypii showing unusually long phloem salivation periods (waveform E1) mostly followed by pathway activities (waveform C) or if followed by phloem ingestion (waveform E2), ingestion was not sustained for more than 10 min. Stylectomy with aphids on susceptible and resistant plants was performed during EPG recording while the stylet tips were phloem inserted. This was followed by dissection of the penetrated leaf section, plant tissue fixation, resin embedding, and ultrathin sectioning for transmission electron microscopic observation in order to study the resistance mechanism in the TGR. The most obvious aspect appeared to be the coagulation of phloem proteins inside the stylet canals and the punctured sieve elements. Stylets of 5 aphids per genotype were amputated during sieve element (SE) salivation (E1) and SE ingestion (E2). Cross-sections of stylet bundles in susceptible melon plants showed that the contents of the stylet canals were totally clear and also, no coagulated phloem proteins occurred in their punctured sieve elements. In contrast, electron-dense coagulations were found in both locations in the resistant plants. Due to calcium binding, aphid saliva has been hypothesized to play an essential role in preventing/suppressing such coagulations that cause occlusion of sieves plate and in the food canal of the aphid's stylets. Doubts about this role of E1 salivation are discussed on the basis of our results.


Subject(s)
Aphids/physiology , Cucumis melo/physiology , Phloem/physiology , Animals , Electric Conductivity , Feeding Behavior/physiology , Microscopy, Electron, Transmission , Plant Leaves/ultrastructure , Plant Proteins/chemistry , Saliva/chemistry , Salivation/physiology
3.
Eur J Neurol ; 20(9): 1277-83, 2013 Sep.
Article in English | MEDLINE | ID: mdl-23647568

ABSTRACT

BACKGROUND AND PURPOSE: An association between high blood pressure (BP) in acute intracerebral hemorrhage (ICH) and hematoma growth (HG) has not been clearly demonstrated. Therefore, the impact of BP changes and course on HG and clinical outcome in patients with acute ICH was determined. METHODS: In total, 117 consecutive patients with acute (<6 h) supratentorial ICH underwent baseline and 24-h CT scans, CT angiography for the detection of the spot sign and non-invasive BP monitoring at 15-min intervals over the first 24 h. Maximum and minimum BP, maximum BP increase and drop from baseline, and BP variability values from systolic BP (SBP), diastolic BP and mean arterial pressure (MAP) were calculated. SBP and MAP loads were defined as the proportion of readings >180 and >130 mmHg, respectively. HG (>33% or >6 ml), early neurological deterioration (END) and 3-month mortality were recorded. RESULTS: Baseline BP variables were unrelated to either HG or clinical outcome. Conversely, SBP 180-load independently predicted HG (odds ratio 1.05, 95% CI 1.010-1.097, P = 0.016), whilst both SBP 180-load (odds ratio 1.04, 95% CI 1.001-1.076, P = 0.042) and SBP variability (odds ratio 1.2, 95% CI 1.047-1.380, P = 0.009) independently predicted END. Although none of the BP monitoring variables was associated with HG in the spot-sign-positive group, higher maximum BP increases from baseline and higher SBP and MAP loads were significantly related to HG in the spot-sign-negative group. CONCLUSIONS: In patients with acute supratentorial ICH, SBP 180-load independently predicts HG, whilst both SBP 180-load and SBP variability predict END.


Subject(s)
Cerebral Hemorrhage/pathology , Hematoma/pathology , Hypertension/complications , Aged , Blood Pressure , Cerebral Angiography , Cerebral Hemorrhage/complications , Female , Hematoma/etiology , Humans , Male , Tomography, X-Ray Computed
4.
Neurology ; 77(17): 1599-604, 2011 Oct 25.
Article in English | MEDLINE | ID: mdl-21998314

ABSTRACT

OBJECTIVE: To investigate the impact of the adjustment of initial intracerebral hemorrhage (ICH) volume by onset-to-imaging time (ultraearly hematoma growth [uHG]) on further hematoma enlargement and outcome in patients with acute ICH. METHODS: We studied 133 patients with acute (<6 hours) supratentorial ICH. Patients underwent baseline and 24-hour CT scans for ICH volume measurement, and a CT angiography (CTA) for the detection of the spot sign. We defined uHG as the relation between baseline ICH volume/onset-to-imaging time, hematoma growth (HG) as hematoma enlargement >33% or >6 mL at 24 hours, early neurologic deterioration (END) as increase ≥4 points in the NIH Stroke Scale score or death at 24 hours, and poor long-term outcome as modified Rankin Scale score >2 at 3 months. RESULTS: The uHG was significantly faster in spot sign patients (p < 0.001), as well as in patients who experienced HG (p = 0.021), END (p < 0.001), 3-month mortality (p < 0.001), and poor long-term outcome (p < 0.001). The uHG improved the accuracy of baseline ICH volume in the prediction of END (sensitivity 93.1% vs 82.8%, specificity 85.3% vs 82.4%) and 3-month mortality (sensitivity 77.5% vs 70%, specificity 87.9% vs 84.6%). A uHG >10.2 mL/hour emerged as the most powerful predictor of HG (odds ratio [OR] 3.55, 95% confidence interval [CI] 1.39-9.07, p = 0.008), END (OR 70.22, 95% CI 14.63-337.03, p < 0.001), 3-month mortality (OR 16.96, 95% CI 5.32-54.03, p < 0.001), and poor long-term outcome (OR 6.19, 95% CI 1.32-28.98, p = 0.021). CONCLUSIONS: The uHG represents a powerful and easy-to-use tool for improving the prediction of HG and outcome in patients with acute ICH.


Subject(s)
Cerebral Hemorrhage/complications , Hematoma/etiology , Hematoma/pathology , Aged , Aged, 80 and over , Cerebral Angiography/methods , Disease Progression , Female , Glasgow Coma Scale , Hematoma/diagnostic imaging , Humans , Logistic Models , Male , Middle Aged , Predictive Value of Tests , Prospective Studies , ROC Curve , Tomography, X-Ray Computed/methods
5.
Stroke Res Treat ; 2011: 182783, 2011.
Article in English | MEDLINE | ID: mdl-21772966

ABSTRACT

An accurate understanding of the mechanisms underlying an individual's response to rt-PA treatment is critical to improve stroke patients' management. We thus reviewed the literature in order to identify biochemical and genetic factors that have been associated with safety and efficacy of rt-PA administration after stroke.

6.
Eur J Neurol ; 18(10): 1279-81, 2011 Oct.
Article in English | MEDLINE | ID: mdl-21463452

ABSTRACT

BACKGROUND: Cerebral amyloid angiopathy (CAA) is a well-established cause of lobar intracerebral hemorrhage (ICH). Familial forms of CAA are because of mutations in the gene encoding the beta-amyloid precursor protein (APP) and duplications of this gene can cause early-onset Alzheimer's disease associated with CAA. However, the contribution of APP genetic variants in the development of sporadic CAA remains unknown. METHODS: The presence of genetic variants in the APP was examined in 78 patients with CAA-related ICH by sequencing exons 16 and 17 coding the ß-amyloid protein and analyzing the presence of possible duplications of APP by microsatellite analysis and quantitative PCR. RESULTS: We did not identify any pathogenic mutation or chromosomal duplication of APP. CONCLUSIONS: Our results suggest that APP genetic variants, point mutations and locus duplication, are not a common cause of CAA-related ICH in the Spanish population.


Subject(s)
Amyloid beta-Protein Precursor/genetics , Cerebral Amyloid Angiopathy/genetics , Cerebral Hemorrhage/genetics , Gene Duplication/genetics , Genetic Loci/genetics , Genetic Predisposition to Disease/genetics , Point Mutation/genetics , Aged , Aged, 80 and over , Cerebral Amyloid Angiopathy/epidemiology , Cerebral Amyloid Angiopathy/metabolism , Cerebral Hemorrhage/epidemiology , Cerebral Hemorrhage/metabolism , Female , Humans , Male , Spain
7.
Eur J Neurol ; 18(6): 826-35, 2011 Jun.
Article in English | MEDLINE | ID: mdl-21122033

ABSTRACT

BACKGROUND: The biologic agents causing leukoaraiosis are unknown. Our aim was to study the genetic basis of leukoaraiosis. METHODS: We analyzed 212 single nucleotide polymorphisms (SNPs) in 142 patients with ischaemic stroke, generating a total of 30,104 genotypes. Seventy-nine subjects (55.6%) presented leukoaraiosis measured by the Fazekas scale and 69 (48.6%) by ARWMC scale. We analyzed the presence of synergic associations between SNPs using the hfcc software. Finally, functional studies were performed in 56 subjects. The Ingenuity Pathways software (ipa) was used to examine the role of the identified genes. RESULTS: Six SNPs were associated with leukoaraiosis using both measuring scales. After logistic regression adjusted for leukoaraiosis risk factors, the rs2252070 of MMP13 (OR = 4.9, 95%CI: 1.34-17.9, P = 0.016), rs662 of PON1 (OR = 0.37, 95%CI: 0.15-0.87, P = 0.024) and rs1800779 of NOS3 (OR = 3.9, 95%CI: 1.38-11.38, P = 0.01) were independently associated with leukoaraiosis under a dominant/recessive model and the rs2290608 of IL5RA (OR = 0.46, 95%CI: 0.25-0.85, P = 0.013) and rs669 of A2M (OR = 2.5, 95%CI: 1.36-4.83, P = 0.004) under an additive model. Computational analysis showed a synergic association of rs10497212-AA of ITGB6 and rs2290608-GG of IL5RA with leukoaraiosis using both scales. (i) ARWMC (P = 1.3 × 10(-4) ) and (ii) Fazekas (P = 4.5 × 10(-5) ). Functional studies showed that the rs669 SNP was associated with plasma levels of A2M (P = 0.012) and A2M levels with leukoaraiosis in Fazekas scale (P = 0.02). ipa analysis revealed that the genes associated with leukoaraiosis were involved in blood-brain barrier (BBB) homeostasis. CONCLUSIONS: Amongst patients with ischaemic stroke, several genes associated with BBB homeostasis could be involved with a higher risk of leukoaraiosis.


Subject(s)
Blood-Brain Barrier/physiopathology , Brain Ischemia/genetics , Genetic Predisposition to Disease/genetics , Homeostasis/genetics , Leukoaraiosis/genetics , Stroke/genetics , Adult , Aged , Aged, 80 and over , Brain Ischemia/metabolism , Brain Ischemia/physiopathology , Female , Gene Expression Regulation , Humans , Interleukin-5 Receptor alpha Subunit/biosynthesis , Interleukin-5 Receptor alpha Subunit/genetics , Leukoaraiosis/metabolism , Leukoaraiosis/physiopathology , Male , Middle Aged , Risk Factors , Stroke/metabolism , Stroke/physiopathology
8.
Int J Neurosci ; 120(4): 245-51, 2010 Apr.
Article in English | MEDLINE | ID: mdl-20374070

ABSTRACT

BACKGROUND: Despite t-PA proven benefits related to vessel reopening, up to 13% of stroke patients suffer reocclusions after t-PA. We aimed to analyze whether a functional polymorphism in a fibrinolysis inhibitor gene [plasminogen activator inhibitor-1 (PAI-1)] might be associated with reocclusion rates after stroke thrombolytic therapy. METHODS: 165 patients with ischemic stroke who received t-PA < 3 h were studied. Reocclusion and recanalization was diagnosed by transcranial Doppler. PAI-1 4G/5G polymorphism determination was performed by sequencing. PAI-1 mRNA was studied by real-time PCR analysis. National institutes of health stroke scale (NIHSS) was serially measured since patients arrival to assess the neurological outcome, and modified ranking scale (mRS) at 3rd month was used to evaluate functional outcome following stroke. RESULTS: PAI-1 4G/4G patients had higher reocclusion rates (4G/4G = 12.5% versus other genotypes = 2.7%, p = 0.025). . In a logistic regression, the 4G/4G genotype was the only factor associated with reocclusion (OR = 15.16 95%, CI = 1.4-163.4, p = 0.025). 4G/4G genotype was also associated with poor functional outcome at 3rd month (4G/4G = 4 versus others genotypes = 3, p = 0.017) and with mRNA levels at 12 h post stroke symptoms onset (4G/4G patients = 2.01% versus other genotypes = 0.68%, p = 0.034). CONCLUSIONS: PAI-1 4G/4G genotype is associated with reocclusion rates and poor functional outcome among stroke patients treated with t-PA.


Subject(s)
Genetic Predisposition to Disease , Plasminogen Activator Inhibitor 1/genetics , Polymorphism, Genetic/genetics , Thrombolytic Therapy/adverse effects , Thrombosis/chemically induced , Thrombosis/genetics , Aged , Aged, 80 and over , Chi-Square Distribution , Female , Gene Frequency , Humans , Male , Plasminogen Activator Inhibitor 1/metabolism , RNA, Messenger/genetics , Statistics, Nonparametric , Stroke/drug therapy , Stroke/genetics , Thrombosis/diagnostic imaging , Time Factors , Ultrasonography, Doppler, Transcranial/methods
9.
Prog Neuropsychopharmacol Biol Psychiatry ; 32(7): 1673-6, 2008 Oct 01.
Article in English | MEDLINE | ID: mdl-18657587

ABSTRACT

Suicidal attempts are relatively frequent and clinically relevant in patients with schizophrenia. Recent studies have found gray matter differences in suicidal and non-suicidal depressive patients. However, no previous neuroimaging study has investigated possible structural abnormalities associated to suicidal behaviors in patients with schizophrenia. A whole-brain magnetic resonance voxel-based morphometric examination was performed on 37 male patients meeting the DSM-IV criteria for schizophrenia. Thirteen (35.14%) patients had attempted suicide. A non-parametric permutation test was computed to perform the comparability between groups. An analysis of covariance (AnCova) model was constructed with a statistical threshold of p<0.05 corrected for multiple comparisons. After controlling for age and severity of illness, results showed significant gray matter density reduction in left superior temporal lobe (p=0.03) and left orbitofrontal cortex (p=0.04) in patients who had attempted suicide when comparing with non-suicidal patients. Although sample size limitations and potential clinical heterogeneity preclude definitive conclusions, these data point to structural differences in key cerebral areas. Neuroimaging studies are necessary to expand our knowledge of biological mechanisms underlying suicide in schizophrenia.


Subject(s)
Frontal Lobe/pathology , Functional Laterality , Schizophrenia/pathology , Schizophrenic Psychology , Suicide/psychology , Temporal Lobe/pathology , Adult , Age Factors , Female , Humans , Magnetic Resonance Imaging , Male , Middle Aged , Psychiatric Status Rating Scales , Statistics, Nonparametric
11.
J Chromatogr A ; 1179(2): 190-7, 2008 Feb 01.
Article in English | MEDLINE | ID: mdl-18096177

ABSTRACT

A new analytical method for the quantitative determination of benzoxazolinones and their degradation products in agricultural soils based on the use of pressurized liquid extraction (PLE) followed by solid-phase extraction (SPE) and then instrumental determination using liquid chromatography-electrospray ionization tandem mass spectrometry (LC-ESI-MS-MS) is described. Using this method, the characterization, separation and quantitative detection of a mixture of two benzoxazolinones, benzoxazolin-2-one (BOA) and 6-methoxybenzoxazolin-2-one (MBOA) and their degradation products, 2-aminophenol (APH), N-(2-hydroxyphenyl)malonamic acid (HMPMA), 2-amino-3-H-phenoxazin-3-one (APO), 9-methoxy-2-amino-3-H-phenoxazin-3-one (AMPO), 2-acetylamino-3-H-phenoxazin-3-one (AAPO) and 2-acetylamino-9-methoxy-2-amino-3-H-phenoxazin-3-one (AAMPO) was achieved. The complete LC-ESI-MS-MS precursor-product ion fragmentation pathways for the degradation products of benzoxazolinones are described for the first time. Quantitative analysis was done in the multiple reaction mode using two specific combinations of precursor-product ion transitions for each compound. The optimized method was quality assessed by the measure of parameter as recovery, linearity, sensitivity, repeatability and reproducibility. Recoveries of the analytes ranged from 53 to 123%. The developed method offered improvements to the sensitivity as compared with our previously LC-MS method, with detection limits down to 2.4-21 ng/g of dry weight. This achievement allows us to identify and quantify for the first time degradation products of benzoxazolinones in real agricultural soil samples. Analytes were found in the range of 20.6-149 ng/g dry weight.


Subject(s)
Benzoxazoles/analysis , Chromatography, High Pressure Liquid/methods , Soil Pollutants/analysis , Spectrometry, Mass, Electrospray Ionization/methods , Tandem Mass Spectrometry/methods , Solid Phase Extraction/methods
12.
Neurosci Lett ; 430(1): 1-6, 2008 Jan 03.
Article in English | MEDLINE | ID: mdl-18055116

ABSTRACT

Our aim was to investigate caspase-3 plasma levels after stroke, its correlation with infarct expansion and neurological outcome. Caspase-3 plasma levels were determined by ELISA at different time points after stroke in 116 t-PA-treated patients and a control group of 40 healthy controls. Neurological status was evaluated by NIHSS scores and functional outcome by modified Rankin Scale. To assess brain infarct growth, serial brain magnetic resonance imaging scans including diffusion- (DWI) and perfusion-weighted (PWI) images were performed in a subgroup of 58 patients. Plasma caspase-3 levels were higher in stroke patients versus the control group throughout the acute phase of stroke. Furthermore, caspase-3 level at 24h was associated with poorer short- and long-term neurological outcome and positively correlated with infarct growth assessed by diffusion-weighted images. Our data suggest that caspase-3 could be involved in recruitment of ischemic brain tissue being a marker of infarct growth.


Subject(s)
Biomarkers/blood , Brain Infarction/enzymology , Caspase 3/blood , Stroke/enzymology , Aged , Brain/enzymology , Brain/pathology , Brain Infarction/blood , Brain Infarction/pathology , Diffusion Magnetic Resonance Imaging , Enzyme-Linked Immunosorbent Assay , Female , Humans , Male , Stroke/blood , Stroke/pathology
13.
Rev Neurol ; 45(9): 556-62, 2007.
Article in Spanish | MEDLINE | ID: mdl-17979086

ABSTRACT

AIM: To review the present knowledge about endothelial progenitor cells (EPCs), their relationship with stroke and their possible therapeutic potential. DEVELOPMENT: Activation of angiogenesis and vasculogenesis after cerebral ischemia is an attempt to recover damaged cerebral tissue. The role of EPCs in angiogenesis/vasculogenesis after brain ischemia remains unknown. Many studies have been published about the isolation, phenotyping and function of EPCs. However, there is not a unique definition for these cells; their origin and function are still an issue of controversy between different research groups. In this review, we summarize the currently used techniques and the most relevant publications about EPCs in experimental models of cerebral ischemia and their role in stroke. CONCLUSIONS: The identification of EPCs in peripheral blood as hematopoietic cells with the ability to differentiate into endothelial cells, broke the paradigm that vasculogenesis was only an embryogenic process. However, better knowledge about the origin and function of EPCs in cerebral ischemia is required. Stimulation of these cells opens a wide new field of cell-based angiogenic therapy that could improve the current stroke treatment.


Subject(s)
Brain Ischemia/surgery , Endothelial Cells/cytology , Hematopoietic Stem Cell Transplantation , Hematopoietic Stem Cells/cytology , Animals , Biomarkers , Brain Ischemia/pathology , Cell Differentiation , Cell Lineage , Cell Movement , Cells, Cultured/transplantation , Cytokines/metabolism , Flow Cytometry , Green Fluorescent Proteins/analysis , Hematopoietic Stem Cells/classification , Humans , Mice , Neovascularization, Physiologic , Rabbits , Rats
14.
Rev. neurol. (Ed. impr.) ; 45(9): 556-562, 1 nov., 2007. ilus, tab
Article in Es | IBECS | ID: ibc-65949

ABSTRACT

Revisar el conocimiento actual sobre células progenitoras endoteliales (CPE), su relación con el ictus y su posible uso terapéutico. Desarrollo. La activación de la angiogénesis y la vasculogénesis tras la isquemia supone un intento de recuperación del tejido cerebral. El papel que pueden tener las CPE en estos procesos tras la isquemia cerebral es aúndesconocido. Son muchos los trabajos que aparecen en la bibliografía sobre el aislamiento, fenotipo y estudio de la funcionalidad de las CPE, pero no existe aún una definición única para estas células, y su origen y función son aún motivo de controversia.En esta revisión se resumen las técnicas utilizadas actualmente para su estudio y se revisan las publicaciones más relevantes en modelos experimentales de isquemia cerebral y de su papel en el ictus isquémico. Conclusiones. La identificaciónde las CPE en sangre periférica como células hematopoyéticas, con capacidad de diferenciarse en células con un fenotipo endotelial, rompió la visión clásica de la vasculogénesis como un proceso exclusivamente embriogénico. Una década después,sólo encontramos tres trabajos publicados en relación con el papel de las CPE tras la isquemia cerebral en humanos. A pesar de que es necesario un mayor conocimiento de la naturaleza y funcionalidad de las CPE en la isquemia cerebral, la potenciaciónde estas células para su uso como terapia celular podría ser una buena herramienta terapéutica basada en la angiogénesis tras la isquemia cerebral


To review the present knowledge about endothelial progenitor cells (EPCs), their relationship with stroke and their possible therapeutic potential. Development. Activation of angiogenesis and vasculogenesis after cerebral ischemia is an attempt to recover damaged cerebral tissue. The role of EPCs in angiogenesis/vasculogenesis after brain ischemia remainsunknown. Many studies have been published about the isolation, phenotyping and function of EPCs. However, there is not a unique definition for these cells; their origin and function are still an issue of controversy between different research groups.In this review, we summarize the currently used techniques and the most relevant publications about EPCs in experimental models of cerebral ischemia and their role in stroke. Conclusions. The identification of EPCs in peripheral blood as hematopoietic cells with the ability to differentiate into endothelial cells, broke the paradigm that vasculogenesis was only anembryogenic process. However, better knowledge about the origin and function of EPCs in cerebral ischemia is required.Stimulation of these cells opens a wide new field of cell-based angiogenic therapy that could improve the current stroke treatment


Subject(s)
Humans , Endothelial Cells , Stem Cells , Stroke/drug therapy , Neovascularization, Physiologic , Flow Cytometry , Cell Separation
15.
J Chromatogr A ; 1157(1-2): 108-14, 2007 Jul 20.
Article in English | MEDLINE | ID: mdl-17507023

ABSTRACT

Despite the increasing success of liquid chromatography (LC) coupled to mass spectrometry (MS), matrix effects have limited the ESI applications. Matrix effects result from co-eluting residual matrix components affecting the ionization efficiency of target analytes and can lead to erroneous results. The present work evaluates the LC-electrospray ionization (ESI)-MS behaviour of benzoxazinoid derivatives in wheat plant material as a case where endogenous matrix components were found to interfere with the ionization of target analytes. When LC-MS was applied to the analysis of foliage and root extracts, significant signal suppressions were observed. To compensate for this matrix signal suppression, different methods were applied: the use of internal standards, the application of standard dilution method and the dilution of the extracts before instrumental determination. The results obtained indicated that evaluation of matrix effects should become an integrated part of quantitative LC-ESI-MS method development and validation.


Subject(s)
Benzoxazines/analysis , Chromatography, Liquid/methods , Plants/chemistry , Spectrometry, Mass, Electrospray Ionization/methods , Reference Standards
16.
J Chromatogr A ; 1052(1-2): 53-9, 2004 Oct 15.
Article in English | MEDLINE | ID: mdl-15527120

ABSTRACT

A new method for the simultaneous analysis of some benzoxazolinones, aminophenoxazinones and malonamic acids was developed based on liquid chromatography (LC) coupled to mass spectrometry (MS), using electrospray ionization (ESI) and operating in positive mode. Different ESI-MS parameters, such as fragmentor voltage, capillary voltage, drying gas flow, nebulizer gas pressure and drying gas temperature, were optimized in order to obtain structural information and to achieve maximum sensitivity. Chromatographic separation was performed by a reversed-phase LC column using a linear gradient of water and methanol. Quality assurance of the developed method was assessed by measuring parameters as linearity, sensitivity, repeatability and reproducibility. Quantification method based on the use of internal standard was developed, selecting synthetic 2-methoxy-2H-1,4-benzoxazin-3(4H)-one as internal standard. Good correlations were obtained for all analytes relative to this compound in the range of 0.05-1.5 ng/microL. Instrumental detection limits were between 0.02 and 0.2 ng/microL. Repeatability and reproducibility studies showed acceptable coefficient of variation values.


Subject(s)
Benzoxazoles/analysis , Chromatography, Liquid/methods , Spectrometry, Mass, Electrospray Ionization/methods , Reference Standards , Reproducibility of Results , Sensitivity and Specificity
17.
J Chromatogr A ; 1047(1): 69-76, 2004 Aug 20.
Article in English | MEDLINE | ID: mdl-15481461

ABSTRACT

Six laboratories from four different countries participated in the first European interlaboratory comparison exercise within the framework of the "Fate and toxicity of allelochemicals (natural plant toxins) in relation to environment and consumer" (FATEALLCHEM) European Union Project. The study, organized between November 2002 and March 2003, involved the analyses of seven benzoxazinone derivatives in two standard solutions and one purified extract of root material. Results are reported from the first phase of the study that examined the variability associated with different detection methods and different laboratories. The analytical strategies were based on liquid chromatography (LC) with diode array detection, LC coupled to mass spectrometry (MS) and LC coupled to tandem MS. When data from all laboratories were pooled, the relative standard deviation values ranged from 2 to 14% for the determination of target compounds in standard solutions, and between 19 and 47% for the analysis in root material. Comparison of the three detection techniques leads to the conclusion that MS approaches are the most accurate and precise techniques for the determination of benzoxazinone derivatives at ng/microL level in plant material.


Subject(s)
Benzoxazines/analysis , Chromatography, Liquid/methods , Plants/chemistry , Chromatography, Liquid/standards , Europe , Laboratories
18.
Theor Appl Genet ; 108(1): 41-52, 2003 Dec.
Article in English | MEDLINE | ID: mdl-14504742

ABSTRACT

Genetic relationships among 125 Spanish melon ( Cucumis melo L.) accessions from a Spanish germplasm collection were assessed using a standard molecular-marker array consisting of 34 random amplified polymorphic DNA (RAPD) markers bands (19 primers) and 72 reference accessions drawn from previous studies. The reference accession array consisted of a broad range [Japanese (19) Crete (17), African (15), and USA and Europe (US/EU, 21)] of horticultural groupings (Group Cantalupensis, Group Conomon, Group Inodorus, Group Flexuosus, and Group Chito), and of melon market classes (e.g., Charentais, U.S. Western and European Shipper types, Ogen, and Galia, Honeydew, and Casaba). Spanish melon accessions (largely Casaba, Group Inodorus) were genetically distinct from the reference accessions and other Group Inodorus melons of different origins. Most African accessions showed common genetic affinities, and grouped with the Group Chito and the Group Conomon accessions examined. Those accession groupings were distinct from all other accessions belonging to Group Cantalupensis, Flexuosus, and Inodorus accessions originating from Crete, Japan, Europe, and the U.S. Genetic diversity was highest in accessions of African origin and lowest in accessions of Spanish origin. Additional RAPD markers (49 primers, 141 bands) and 22 selected agronomic traits (quantitative and qualitative) were then used to assess the genetic diversity among Spanish accessions. While cluster analysis using fruit characteristics grouped accessions into cultivars, RAPD-based genetic-distance estimate did not provide consistent accession groupings either by cultivar or geographic origin. While the highest level of polymorphism was detected among melons originating from the central region of Spain, and in the Rochet cultivar, accessions from the Andalucía region and Green cultivars were comparatively less diverse. These results indicate that the Spanish melon accessions could be used to broaden the genetic base of local and foreign Casaba germplasm, to enhance the genetic diversity of U.S and European commercial melon germplasm, and to delineate collection strategies for acquisition of additional Spanish landraces.


Subject(s)
Cucumis melo/genetics , DNA, Plant/genetics , Genetic Markers , Genetic Variation , Evolution, Molecular , Geography , Phenotype , Phylogeny , Random Amplified Polymorphic DNA Technique
19.
J Environ Monit ; 3(5): 475-82, 2001 Oct.
Article in English | MEDLINE | ID: mdl-11695114

ABSTRACT

The purpose of this paper is to relate the implementation of Directive 76/464/CEE concerning the survey of priority dangerous substances and indicate the main priority pollutants encountered throughout a systematic monitoring program carried out in Portugal during a period of 14 months (April 1999-May 2000). Contrary to what it seems, the implementation of such a Directive is not straightforward owing to the large number of compounds and samples to be analyzed at trace levels. During this period of time, 115 priority semivolatile organic compounds (SVOCs), 41 volatile organic compounds (VOCs), six organotin compounds, 14 heavy metals, phosphate, nitrates, nitrites and ammonia were determined in 644 surface water samples (corresponding to 14 months and 46 sites). In addition, priority SVOCs were also determined in sediment, mussels and fish (muscle and liver). This paper reports the procedure and analytical tools used and necessary to determine the levels of 115 priority toxic and persistent semivolatile organic compounds selected from the EC Council Directive list (76/464/EEC). An advanced analytical protocol was developed involving enrichment of water samples in Oasis solid-phase extraction cartridges (SPE) in the Lisbon laboratory with a Gilson ASPEC XL automated extraction system and by sending the enriched cartridges to Barcelona by aeroplane at 4 degrees C, where elution and analysis were performed. Final determination was performed with gas chromatography-electron ionization mass spectrometry (GC-EI-MS). Acidic herbicides were determined by liquid chromatography with diode array detection. Owing to the great amount of data generated throughout the monitoring study, statistical analysis of the more representative contaminants was performed, allowing the identification of the more relevant contamination sources, percentages of findings and the description of their temporal and spatial (geographical) distributions. Recommendations and compounds that should be included in future monitoring programs are given.


Subject(s)
Environmental Monitoring/methods , Water Pollutants, Chemical/analysis , Environmental Monitoring/standards , Gas Chromatography-Mass Spectrometry , Guideline Adherence , Organic Chemicals/analysis , Portugal , Specimen Handling , Volatilization
20.
J Chromatogr A ; 938(1-2): 57-65, 2001 Dec 14.
Article in English | MEDLINE | ID: mdl-11771847

ABSTRACT

Polycyclic aromatic hydrocarbons (PAHs) are an important group of organic contaminants present in sewage sludge. Due to their persistence and toxic potential, information about their presence in sewage sludge is needed in order to assess applicability on agricultural land. A method for the gas chromatographic-mass spectrometric (GC-MS) determination was developed and applied to the trace determination of PAHs present in sewage sludge samples from six wastewater treatment plants (WWTPs) differing in the type of treatment and the origin of wastewater. PAHs were extracted from freeze-dried samples by a dichloromethane-methanol (2:1) mixture in a sonication bath. The sludge extracts were cleaned-up by an alumina column. The method showed recovery values varying from 60 to 98%. Four surrogate standards ([2H8]naphthalene, [2H10]anthracene, [2H12]benzo[a]anthracene, and [2H12]benzo[ghi]perylene) were used for quantitation by GC-MS. A reference sludge sample was analysed in order to validate the method. The sum of the 16 US Environmental Protection Agency PAHs analysed in the sewage sludge samples varied from 1.13 to 5.52 mg/kg. No significant difference between the different WWTPs was found.


Subject(s)
Industrial Waste , Polycyclic Compounds/analysis , Sewage/chemistry , Calibration , Gas Chromatography-Mass Spectrometry/methods , Reproducibility of Results
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