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1.
Heart ; 109(15): 1175-1182, 2023 07 12.
Artículo en Inglés | MEDLINE | ID: mdl-37137675

RESUMEN

AIMS: Hypertrophic cardiomyopathy (HCM) is characterised by left ventricular hypertrophy (LVH), myocardial fibrosis, enhanced oxidative stress and energy depletion. Unbound/loosely bound tissue copper II ions are powerful catalysts of oxidative stress and inhibitors of antioxidants. Trientine is a highly selective copper II chelator. In preclinical and clinical studies in diabetes, trientine is associated with reduced LVH and fibrosis, and improved mitochondrial function and energy metabolism. Trientine was associated with improvements in cardiac structure and function in an open-label study in patients with HCM. METHODS: The Efficacy and Mechanism of Trientine in Patients with Hypertrophic Cardiomyopathy (TEMPEST) trial is a multicentre, double-blind, parallel group, 1:1 randomised, placebo-controlled phase II trial designed to evaluate the efficacy and mechanism of action of trientine in patients with HCM. Patients with a diagnosis of HCM according to the European Society of Cardiology Guidelines and in New York Heart Association classes I-III are randomised to trientine or matching placebo for 52 weeks. Primary outcome is change in left ventricular (LV) mass indexed to body surface area, measured using cardiovascular magnetic resonance. Secondary efficacy objectives will determine whether trientine improves exercise capacity, reduces arrhythmia burden, reduces cardiomyocyte injury, improves LV and atrial function, and reduces LV outflow tract gradient. Mechanistic objectives will determine whether the effects are mediated by cellular or extracellular mass regression and improved myocardial energetics. CONCLUSION: TEMPEST will determine the efficacy and mechanism of action of trientine in patients with HCM. TRIAL REGISTRATION NUMBERS: NCT04706429 and ISRCTN57145331.


Asunto(s)
Cardiomiopatía Hipertrófica , Trientina , Humanos , Trientina/uso terapéutico , Cobre/uso terapéutico , Cardiomiopatía Hipertrófica/diagnóstico , Cardiomiopatía Hipertrófica/tratamiento farmacológico , Cardiomiopatía Hipertrófica/complicaciones , Corazón , Hipertrofia Ventricular Izquierda/tratamiento farmacológico , Hipertrofia Ventricular Izquierda/etiología , Hipertrofia Ventricular Izquierda/prevención & control , Fibrosis
2.
Crit Rev Anal Chem ; : 1-18, 2023 Jan 13.
Artículo en Inglés | MEDLINE | ID: mdl-36637361

RESUMEN

Advances in inductively coupled plasma mass spectrometry and the methods used to prepare isotopically enriched standards, allow for the high accuracy measurement of metalloproteins by isotope dilution mass spectrometry. This technique has now reached a level of maturity whereby a step change in the accuracy, precision, and traceability of, in particular, clinical, and biomedical measurements is achievable. Current clinical measurements, which require low limits of detection in the presence of complex sample matrices, use indirect methods based on immunochemistry for the study of human disease. However, this approach suffers from poor traceability, requiring comparisons based on provision of matrix-based reference materials, used as analytical standards. This leads to difficulty when changes in the reference material are required, often resulting in a lack of interlaboratory and temporal comparability in clinical results and reference ranges. In this review, we focus on the most important metalloproteins for clinical studies, to illustrate how the attributes of chromatography coupled to inorganic mass spectrometry can be used for the direct measurement of metalloproteins such as hemoglobin, transferrin, and ceruloplasmin. By using this approach, we hope to demonstrate how isotope dilution analysis can be used as a reference method to improve traceability and underpin clinical, biomedical, and other biological measurements.

3.
Maedica (Bucur) ; 16(2): 207-210, 2021 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-34621341

RESUMEN

Aim: This report aims to render a proposed concept model for cancer risk in Nigerian electronic waste exposure by making deductions from data on the assessment of Nigerians' exposure to toxic metals in e-waste, using biomarkers of exposure and genotoxicity to evaluate the risk of cancer development. Material and methods: In the cross-sectional study, 632 consenting participants, consisting of 381 e-waste workers (EW) and 120 environmental e-waste exposed participants (EEEP), age-matched with 131 unexposed participants (controls), were enrolled from Benin, Lagos and Ibadan, Southwestern Nigeria. Levels of selected toxic metals in blood and essential metals in serum were determined using inductively coupled plasma-mass spectrometry. Oxidative stress biomarkers, including malondialdehyde and uric acid (UA), and activities of enzymatic antioxidants [catalase, superoxide dismutase (SOD), γ-glutamyltransferase (GGT) and glutathione peroxidase (GPx)], were determined in serum using standard methods like spectrophotometry. Genotoxicity biomarkers - wild-type tumour suppressor protein (wt-p53), 8-oxoguanine-DNA glycosylase (OGG1), and 8-hydroxy-2'-deoxyguanosine (8-OHdG); glutathione (GSH); and tumour markers [prostate-specific antigen (PSA) and alpha-fetoprotein] - were determined in serum using ELISA. Micronucleus assay was carried out using microscopy. Data were analysed using ANOVA and Pearson's correlation coefficient at α0.05. Results: There was evidence indicating elevated levels of genotoxic toxic metals, decreased levels of genome protective metals, increased oxidative stress markers as well as reduced cellular antioxidants in both EW and EEEP compared to controls. Additionally, the levels of wt-p53 in EW and EEEP were lower than controls, while OGG1 activity in EEEP was higher. The PSA and alpha-fetoprotein in EW were more elevated than EEEP and controls, respectively. The MnPCE/1000PCE in EW was higher than EEEP and controls. Conclusion: The proposed schematic model could be adopted to illustrate cancer risk in Nigerian population exposed to electronic waste.

4.
Haemophilia ; 27(3): 425-433, 2021 May.
Artículo en Inglés | MEDLINE | ID: mdl-33749973

RESUMEN

INTRODUCTION: Cardiovascular events in patients with inherited bleeding disorders are challenging to manage. The risk of bleeding secondary to antithrombotic treatment must be balanced against the risk of thrombosis secondary to haemostatic therapy. METHODS: Patients with inherited bleeding disorders with coronary artery bypass grafting (CABG), percutaneous coronary intervention (PCI) or atrial fibrillation (AF) from a single centre (2010-2018) are included. RESULTS: A total of 11 patients undergoing CABG (n = 3), PCI (n = 5) or with AF (n = 3) and a diagnosis of haemophilia A (n = 8), haemophilia B (n = 1), factor XI deficiency (n = 1) and von Willebrand disease (n = 1) managed by a multidisciplinary team are reported. In patients undergoing CABG, factor levels were normalized for 7-10 days with trough levels of 70-80% with severe patients continuing high-dose factor prophylaxis (trough 20-30%) three weeks post-operatively with daily aspirin. In a patient with mild haemophilia A and an inhibitor, recombinant factor VIIa dosing was monitored with thromboelastometry. For PCI, a 3rd-generation drug-eluting stent with one month of dual antiplatelet therapy in addition to high-dose prophylaxis as needed was preferred. Patients with AF and severe haemophilia did not receive antithrombotic treatment, and a thrombin generation assay was used to guide heparin dosing in mild haemophilia. CONCLUSION: Our experience demonstrates the importance of interdisciplinary communication to identify strategies that decrease the risk of bleeding and thrombosis. The use of extended, increased intensity prophylaxis facilitated antiplatelet therapy. Global assays may help balance the intensity of haemostatic and antithrombotic treatment.


Asunto(s)
Fibrilación Atrial , Enfermedades Cardiovasculares , Enfermedad de la Arteria Coronaria , Stents Liberadores de Fármacos , Intervención Coronaria Percutánea , Anticoagulantes/uso terapéutico , Fibrilación Atrial/tratamiento farmacológico , Quimioterapia Combinada , Fibrinolíticos/uso terapéutico , Humanos , Inhibidores de Agregación Plaquetaria/uso terapéutico
5.
Anal Chim Acta ; 1098: 27-36, 2020 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-31948584

RESUMEN

Biomedical analytical methods often rely on indirect measurements, such as immunoassays, which can lack effective metrological traceability. In the nephelometric determination of ceruloplasmin (Cp), an important protein whose circulating level is altered in Wilson's disease (WD), the anti-Cp antibody used is not specific for the biologically active holoprotein so the assay can overestimate the concentration of Cp due to the presence of the apoprotein. By providing quantitation using elemental standards, the use of strong anion exchange chromatography (SAX) coupled to triple quadrupole inductively coupled plasma mass spectrometry (ICP-MS-MS) can overcome the drawbacks of methods for the measurement of metalloproteins reliant on immunoassays. In the current study, a SAX-ICP-MS-MS method for Cp quantification was designed and tested in samples of blood serum of WD patients and healthy controls. Using standards based on a copper-EDTA complex for calibration, the method provides relatively simple quantification of Cp with the limit of detection of 0.1 µg L-1 (limit of quantification 0.4 µg L-1). The method was also used to investigate the copper species separated by using a 30 kDa cut-off ultrafiltration device. The so-called "exchangeable" copper fraction is considered as an alternative clinical biomarker of WD. Using the designed speciation approach, it was shown that the ultrafiltration method can overestimate the "exchangeable" copper fraction due to a removal of copper from Cp. This was confirmed by comparing the enzymatic activity of the fractions. Thus, the specificity of the "exchangeable" copper test can be ensured only under strict maintenance of ultrafiltration conditions.


Asunto(s)
Investigación Biomédica , Cobre/sangre , Degeneración Hepatolenticular/sangre , Cromatografía por Intercambio Iónico/instrumentación , Degeneración Hepatolenticular/diagnóstico , Humanos , Espectrometría de Masas/instrumentación
6.
World J Gastrointest Endosc ; 10(1): 37-44, 2018 Jan 16.
Artículo en Inglés | MEDLINE | ID: mdl-29375740

RESUMEN

AIM: To investigate the impact of endoscopic ultrasound-guided fine-needle aspiration (EUS-FNA) and positron emission tomography-computed tomography (PET-CT) in the nodal staging of upper gastrointestinal (GI) cancer in a tertiary referral centre. METHODS: We performed a retrospective review of prospectively recorded data held on all patients with a diagnosis of upper GI cancer made between January 2009 and December 2015. Only those patients who had both a PET-CT and EUS with FNA sampling of a mediastinal node distant from the primary tumour were included. Using a positive EUS-FNA result as the gold standard for lymph node involvement, the sensitivity, specificity, positive and negative predictive values (PPV and NPV) and accuracy of PET-CT in the staging of mediastinal lymph nodes were calculated. The impact on therapeutic strategy of adding EUS-FNA to PET-CT was assessed. RESULTS: One hundred and twenty one patients were included. Sixty nine patients had a diagnosis of oesophageal adenocarcinoma (Thirty one of whom were junctional), forty eight had oesophageal squamous cell carcinoma and four had gastric adenocarcinoma. The FNA results were inadequate in eleven cases and the PET-CT findings were indeterminate in two cases, therefore thirteen patients (10.7%) were excluded from further analysis. There was concordance between PET-CT and EUS-FNA findings in seventy one of the remaining one hundred and eight patients (65.7%). The sensitivity, specificity, PPV and NPV values of PET-CT were 92.5%, 50%, 52.1% and 91.9% respectively. There was discordance between PET-CT and EUS-FNA findings in thirty seven out of one hundred and eight patients (34.3%). MDT discussion led to a radical treatment pathway in twenty seven of these cases, after the final tumour stage was altered as a direct consequence of the EUS-FNA findings. Of these patients, fourteen (51.9%) experienced clinical remission of a median of nine months (range three to forty two months). CONCLUSION: EUS-FNA leads to altered staging of upper GI cancer, resulting in more patients receiving radical treatment that would have been the case using PET-CT staging alone.

7.
Ann Clin Biochem ; 54(3): 362-369, 2017 May.
Artículo en Inglés | MEDLINE | ID: mdl-27422134

RESUMEN

Background Patients with metal-on-metal hip replacements require testing for cobalt and chromium. There may also be a need to test for titanium, which is used in the construction of the femoral stem in total hip replacements. It is not possible to use quadrupole inductively coupled plasma mass spectrometry due to interferences. Methods Titanium was measured using inductively coupled plasma optical emission spectroscopy using the emission line at 336.1 nm and Y (internal standard) at 371.0 nm. Internal quality control materials were prepared for blood and serum and concentrations assigned using a sector field-inductively coupled plasma mass spectrometer. A candidate whole blood certified reference material was also evaluated. Results The method had detection and quantitation limits of 0.6 and 1.9 µg/L, respectively. The respective bias (%) and measurement uncertainty ( U) (k = 2) were 3.3% and 2.0 µg/L (serum) and - 1.0% and 1.4 µg/L (whole blood). The respective repeatability and intermediate precision (%) were 5.1% and 10.9% (serum) and 2.4% and 8.6% (whole blood). The concentration of titanium was determined in patients' samples, serum (median = 2.4 µg/L, n = 897) and whole blood (median = 2.4 µg/L, n = 189). Serum is recommended for monitoring titanium in patients, since the concentration is higher than in whole blood and the matrix less problematic. In hip fluid samples, the concentrations were much higher (mean 58.5 µg/L, median 5.1 µg/L, n = 83). Conclusions A method based on inductively coupled plasma optical emission spectroscopy was developed and validated for measuring titanium in clinical samples.


Asunto(s)
Artroplastia de Reemplazo de Cadera , Espectrofotometría Atómica/normas , Titanio/sangre , Cromo/sangre , Cobalto/sangre , Femenino , Prótesis de Cadera , Humanos , Límite de Detección , Masculino , Control de Calidad , Estándares de Referencia
9.
Clin Chem Lab Med ; 54(12): 1921-1928, 2016 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-27174868

RESUMEN

BACKGROUND: Proficiency testing or external quality assessment schemes (PT/EQASs) are an important method of assessing laboratory performance. As each scheme establishes assigned values and acceptable ranges for the analyte according to its own criteria, monitoring of participant performance varies according to the scheme and can lead to conflicting conclusions. METHODS: Standard deviations (SDs) for PT were derived from Thompson's and biological variation models applied to blood and urine manganese (Mn) robust data from four EQASs from North America and Europe. The fitness for purpose was verified by applying these SDs to individual results. RESULTS: Using Thompson characteristic function the relationship between SD and Mn concentration, expressed in nmol/L was the square root of [19.72+(0.07712×Mn concentration2)] for blood and the square root of [6.772+(0.09852×Mn concentration2)] for urine. While the biological variation model was not suitable for urine, it produced an acceptable range for blood as ±54.4 nmol/L (assigned value ≤320 nmol/L) or 17% (assigned value >320 nmol/L). For blood, individual performance evaluated by the two approaches led to similar conclusions. CONCLUSIONS: The biological variation model can be used to propose quality specifications for blood, however it could not be applied to urine. The Thompson characteristic function model could be applied to derive quality specifications for Mn in urine and, to a lesser extent in blood. The more lenient quality specifications for blood highlight the difficulty of determining Mn in this matrix. Further work is needed to harmonize PT, such as using assigned ranges for the specimens.


Asunto(s)
Técnicas de Laboratorio Clínico/normas , Manganeso/sangre , Manganeso/orina , Humanos
10.
Ann Surg Oncol ; 23(2): 573-8, 2016 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-26286197

RESUMEN

BACKGROUND: Merkel cell carcinoma (MCC) is an uncommon aggressive skin malignancy. Published series mainly focus on wide excision, which can be difficult at some sites (e.g., face) and in patients with comorbidities. In British Columbia, an approach of conservative surgery followed by radiotherapy is common. MATERIALS AND METHODS: This is a retrospective review of 179 patients treated for MCC with curative intent in British Columbia. RESULTS: Totals of 68, 63, and 37 patients underwent narrow excision of primary, attempted wide excision, and biopsy only, respectively. Adjuvant radiotherapy reduced local recurrence after narrow excision (<10 mm margin) from 25 to 4.9 % (p = .03) and was effective in the presence of microscopic positive margins. Local recurrence rate was 7.1 % if the margin was >10 mm irrespective of radiation use. Local RFS was improved by adjuvant radiation therapy (RT) (p = 0.04), and there was a trend to reduced nodal relapse after elective nodal RT (p = .07). Irradiation of macroscopic tumor at 37 primary and 33 nodal sites provided 5-year local and nodal RFS of 90 and 75 %, respectively. The 5-year cancer specific survival was 77 % and was not improved by the use of adjuvant radiotherapy. CONCLUSIONS: Local excision plus adjuvant RT is an effective treatment for MCC. Adjuvant radiation should be considered when the excision margin is <1 cm.


Asunto(s)
Carcinoma de Células de Merkel/radioterapia , Carcinoma de Células de Merkel/cirugía , Recurrencia Local de Neoplasia/radioterapia , Recurrencia Local de Neoplasia/cirugía , Neoplasias Cutáneas/radioterapia , Neoplasias Cutáneas/cirugía , Adulto , Anciano , Anciano de 80 o más Años , Colombia Británica , Carcinoma de Células de Merkel/patología , Terapia Combinada , Manejo de la Enfermedad , Femenino , Estudios de Seguimiento , Humanos , Masculino , Persona de Mediana Edad , Recurrencia Local de Neoplasia/patología , Estadificación de Neoplasias , Pronóstico , Radioterapia Adyuvante , Estudios Retrospectivos , Neoplasias Cutáneas/patología , Tasa de Supervivencia
11.
Anal Bioanal Chem ; 407(16): 4541-54, 2015 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-25874977

RESUMEN

Hip replacements are used to improve the quality of life of people with orthopaedic conditions, but the use of metal-on-metal (MoM) arthroplasty has led to poor outcomes for some patients. These problems are related to the generation of micro- to nanosized metal wear particles containing Cr, Co or other elements, but the current analytical methods used to investigate the processes involved do not provide sufficient information to understand the size or composition of the wear particles generated in vivo. In this qualitative feasibility study, asymmetric flow field-flow fractionation (AF(4)) coupled with inductively coupled plasma mass spectrometry (ICP-MS) was used to investigate metal protein binding and the size and composition of wear metal particles present in serum and hip aspirates from MoM hip replacement patients. A well-established HPLC anion exchange chromatography (AEC) separation system coupled to ICP-MS was used to confirm the metal-protein associations in the serum samples. Off-line single particle ICP-MS (spICP-MS) analysis was used to confirm the approximate size distribution indicated by AF(4) of the wear particles in hip aspirates. In the serum samples, AF(4) -ICP-MS suggested that Cr was associated with transferrin (Tf) and Co with albumin (Alb) and an unidentified species; AEC-ICP-MS confirmed these associations and also indicated an association of Cr with Alb. In the hip aspirate sample, AF(4)-ICP-MS suggested that Cr was associated with Alb and Tf and that Co was associated with Alb and two unidentified compounds; AEC analysis confirmed the Cr results and the association of Co with Alb and a second compound. Enzymatic digestion of the hip aspirate sample, followed by separation using AF(4) with detection by UV absorption (280 nm), multi-angle light scattering and ICP-MS, suggested that the sizes of the Cr-, Co- and Mo-containing wear particles in a hip aspirate sample were in the range 40-150 nm. Off-line spICP-MS was used to confirm these findings for the Co- and Cr-containing nanoparticles. Whilst limited in scope, the results are sufficient to show the interaction of ions with transport proteins and give an indication of particle size, providing useful pathological indices. As such, the methods indicate a new way forward for in vivo investigation of the processes which lead to tissue necrosis and hip loosening in patients with MoM hip replacements.


Asunto(s)
Artroplastia de Reemplazo de Cadera , Líquidos Corporales/química , Fraccionamiento de Campo-Flujo , Metaloproteínas/análisis , Metales/análisis , Estudios de Factibilidad , Humanos , Espectrometría de Masas
12.
J Pharm Biomed Anal ; 106: 210-7, 2015 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-25455724

RESUMEN

Many pharmaceuticals contain metals, either as part of the active compound or within the formulation. They are also found in related products such as dietary supplements and toiletries. Concentrations of metals in biological fluids or tissues from patients taking these agents, are measured where there may be an adverse reaction, dose-related toxicity or for therapeutic drug monitoring. Other situations, for analysis of environmental samples include occupational exposure (manufacture, administration to patients, pharmaceutical research) or in investigations of poisoning. Highly sensitive and accurate analytical methods are now available to determine the total metal concentration in a specific sample, but also to measure the specific chemical form of the drug, a metabolite of the drug, or the drug's interaction with important cellular components, such as DNA. The use of ICP-MS to measure total metal concentrations, or HPLC coupled to ICP-MS for the more complex speciation measurements, will depend on the type of information that is required. For the investigation of the drug species present, other complementary analytical techniques such as electrospray mass spectrometry (LC-MS/MS) are required for a full structural elucidation of the analytes. In this current publication we highlight the measurement of two metal(loid) based pharmaceutical drugs for the treatment of cancer. One 4-(N-(S-glutathionylacetyl)amino) phenylarsenoxide (GSAO) containing arsenic and under investigation for the treatment of solid tumours, and the second cis-diamminedichloroplatinum (II) (cisplatin) containing platinum and widely used in the clinical setting as a front line treatment against various neplasias in particular testicular, ovarian, bladder and head and neck cancers.


Asunto(s)
Antineoplásicos/análisis , Arsenicales/análisis , Cisplatino/análisis , Glutatión/análogos & derivados , Animales , Cromatografía Liquida/métodos , Glutatión/análisis , Humanos , Espectrometría de Masas/métodos , Espectrofotometría Atómica/métodos
13.
BMJ Case Rep ; 20142014 Jul 08.
Artículo en Inglés | MEDLINE | ID: mdl-25006053

RESUMEN

An underweight 15-year-old boy had a video capsule endoscopy (VCE) to investigate iron deficient anaemia associated with elevated platelet and white cell counts. The suspicion was of subclinical small bowel Crohn's disease after the findings of a radiolabelled white cell scan. The VCE in May 2007 found patchy inflammation and superficial ulcers in the terminal ileum consistent with Crohn's disease. By March 2008, the patient remained asymptomatic but the capsule had not passed. He was treated with steroids to improve the inflammation and allow the capsule to pass. This was unsuccessful. Abdominal X-rays appeared to show that it was in the rectum. CT of the abdomen and pelvis in July 2012 showed that it was actually in the mid-distal ileum within a mass of inflamed and matted small bowel loops. He was last reviewed in March 2014. He has now retained the capsule asymptomatically for 6 years and 10 months.


Asunto(s)
Endoscopios en Cápsulas , Enfermedad de Crohn/diagnóstico , Cuerpos Extraños/diagnóstico por imagen , Íleon/diagnóstico por imagen , Adolescente , Endoscopía Capsular , Humanos , Masculino , Radiografía , Delgadez , Adulto Joven
14.
Ann Surg Oncol ; 21(11): 3401-5, 2014 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-25001091

RESUMEN

BACKGROUND: Achieving clear surgical margins in Merkel cell carcinoma (MCC) can be difficult due to tumor location or patient comorbidity. Clinical impression suggests that radiation treatment achieves good control of macroscopic disease. METHODS: A retrospective chart review was undertaken of all patients with pathological evidence of MCC and treated with curative intent at the BC Cancer Agency between 1979 and 2007. This is a report on the outcomes of those with gross disease treated with radiotherapy, without radical surgery. RESULTS: Fifty-seven patients received definitive radiotherapy to the primary and/or nodal disease. Median age was 75 years and median follow-up was 34 months (84.5 months for those alive at last follow-up). American Joint Committee on Cancer (AJCC) stage distribution was 23, 19, and 58 % for stages I, II, and III, respectively. Tumor control at sites treated for macroscopic disease was 88 % at 12 months and 82 % at 2 years, and 5-year local relapse-free survival (RFS) was 90 %. Five-year RFS, cancer-specific survival (CSS), and overall survival were 57, 68, and 39 %, respectively. On univariate and multivariate analyses, only male sex was associated with a worse RFS, and a radiotherapy dose >50 Gy was associated with a better CSS. LIMITATIONS: The retrospective nature of the study and small sample size limit the strength of the conclusions. CONCLUSIONS: Radical radiotherapy is effective in the curative treatment of MCC, especially in patients who would tolerate wide surgical excision poorly, or where it would cause significant cosmetic or functional deficits.


Asunto(s)
Carcinoma de Células de Merkel/radioterapia , Carcinoma de Células de Merkel/cirugía , Radioterapia , Neoplasias Cutáneas/radioterapia , Neoplasias Cutáneas/cirugía , Adulto , Anciano , Anciano de 80 o más Años , Carcinoma de Células de Merkel/mortalidad , Carcinoma de Células de Merkel/patología , Terapia Combinada , Femenino , Estudios de Seguimiento , Humanos , Masculino , Persona de Mediana Edad , Estadificación de Neoplasias , Pronóstico , Estudios Retrospectivos , Neoplasias Cutáneas/mortalidad , Neoplasias Cutáneas/patología , Tasa de Supervivencia
15.
Ann Clin Biochem ; 51(Pt 3): 386-91, 2014 May.
Artículo en Inglés | MEDLINE | ID: mdl-24081185

RESUMEN

BACKGROUND: Measurement of selenium in serum is an important clinical biomarker of nutritional status. The presence of gadolinium (Gd) in samples following administration of the contrast agents used for magnetic resonance imaging (MRI) results in a significant positive bias when using quadrupole inductively coupled plasma mass spectrometry (Q-ICP-MS). METHODS: Three instrumental set-ups were assessed: standard mode with no collision gas and collision cell mode with either a hydrogen:helium mixture or hydrogen. The effect of Gd on the selenium (Se) signal was assessed using external quality assurance (EQA) specimens and internal quality control (IQC) materials, both unspiked and spiked with Gd. Serum previously shown to contain high concentrations of Gd-containing contrast agents were also analysed. RESULTS: Recoveries of Se in the spiked compared to the unspiked samples were: between 500% and 1300% using standard mode; 100% and 29,000% using collision cell mode with hydrogen:helium mixture; and between 99% and 103% using hydrogen. The use of H2 in the collision cell provided accurate results, indicating that the charge exchange reaction (CER) of Gd(2+) with H2 removes this interference. Analysis of patient serum known to contain the Gd contrast agent using the method gave results within the selenium reference range (adults 0.89-1.65 µmol/L). The presence of Gd, as low as 0.2 mg/L, in serum samples causes a positive interference on the measurement of Se by ICP-MS. CONCLUSIONS: Using a CER mode with pure H2 in the collision cell it was possible to fully remove the interference due to Gd(2+) from the signal for Se.


Asunto(s)
Análisis Químico de la Sangre/métodos , Gadolinio/sangre , Espectrometría de Masas/métodos , Selenio/sangre , Artefactos , Gadolinio/química , Hospitales , Humanos
16.
J Toxicol Environ Health A ; 75(13-15): 893-908, 2012.
Artículo en Inglés | MEDLINE | ID: mdl-22788375

RESUMEN

Mining activities may affect the health of miners and communities living near mining sites, and these health effects may persist even when the mine is abandoned. During mining processes various toxic wastes are produced and released into the surrounding environment, resulting in contamination of air, drinking water, rivers, plants, and soils. In a geochemical sampling campaign undertaken in the Panasqueira Mine area of central Portugal, an anomalous distribution of several metals and arsenic (As) was identified in various environmental media. Several potentially harmful elements, including As, cadmium (Cd), chromium (Cr), manganese (Mn), nickel (Ni), lead (Pb), and selenium (Se), were quantified in blood, urine, hair, and nails (toe and finger) from a group of individuals living near the Panasqueira Mine who were environmentally and occupationally exposed. A group with similar demographic characteristics without known exposure to mining activities was also compared. Genotoxicity was evaluated by means of T-cell receptor (TCR) mutation assay, and percentages of different lymphocyte subsets were selected as immunotoxicity biomarkers. Inductively coupled plasma-mass spectrometry (ICP-MS) and inductively coupled plasma-atomic emission spectrometry (ICP-AES) analysis showed elevated levels of As, Cd, Cr, Mn, and Pb in all biological samples taken from populations living close to the mine compared to controls. Genotoxic and immunotoxic differences were also observed. The results provide evidence of an elevated potential risk to the health of populations, with environmental and occupational exposures resulting from mining activities. Further, the results emphasize the need to implement preventive measures, remediation, and rehabilitation plans for the region.


Asunto(s)
Exposición a Riesgos Ambientales , Inmunosupresores/metabolismo , Metaloides/metabolismo , Metales Pesados/metabolismo , Minería , Mutágenos/metabolismo , Exposición Profesional , Anciano , Arsénico/administración & dosificación , Arsénico/sangre , Arsénico/metabolismo , Arsénico/orina , Biomarcadores/sangre , Biomarcadores/metabolismo , Biomarcadores/orina , Femenino , Genes Codificadores de los Receptores de Linfocitos T/efectos de los fármacos , Cabello/metabolismo , Intoxicación por Metales Pesados , Humanos , Inmunosupresores/administración & dosificación , Inmunosupresores/sangre , Inmunosupresores/orina , Subgrupos Linfocitarios/efectos de los fármacos , Masculino , Metaloides/administración & dosificación , Metaloides/sangre , Metaloides/orina , Metales Pesados/administración & dosificación , Metales Pesados/sangre , Metales Pesados/orina , Persona de Mediana Edad , Mutágenos/administración & dosificación , Mutación/efectos de los fármacos , Uñas/metabolismo , Intoxicación/sangre , Intoxicación/etiología , Intoxicación/metabolismo , Intoxicación/orina , Portugal/epidemiología , Selenio/administración & dosificación , Selenio/sangre , Selenio/metabolismo , Selenio/orina
18.
N Engl J Med ; 365(25): 2357-65, 2011 Dec 22.
Artículo en Inglés | MEDLINE | ID: mdl-22149959

RESUMEN

BACKGROUND: Hemophilia B, an X-linked disorder, is ideally suited for gene therapy. We investigated the use of a new gene therapy in patients with the disorder. METHODS: We infused a single dose of a serotype-8-pseudotyped, self-complementary adenovirus-associated virus (AAV) vector expressing a codon-optimized human factor IX (FIX) transgene (scAAV2/8-LP1-hFIXco) in a peripheral vein in six patients with severe hemophilia B (FIX activity, <1% of normal values). Study participants were enrolled sequentially in one of three cohorts (given a high, intermediate, or low dose of vector), with two participants in each group. Vector was administered without immunosuppressive therapy, and participants were followed for 6 to 16 months. RESULTS: AAV-mediated expression of FIX at 2 to 11% of normal levels was observed in all participants. Four of the six discontinued FIX prophylaxis and remained free of spontaneous hemorrhage; in the other two, the interval between prophylactic injections was increased. Of the two participants who received the high dose of vector, one had a transient, asymptomatic elevation of serum aminotransferase levels, which was associated with the detection of AAV8-capsid-specific T cells in the peripheral blood; the other had a slight increase in liver-enzyme levels, the cause of which was less clear. Each of these two participants received a short course of glucocorticoid therapy, which rapidly normalized aminotransferase levels and maintained FIX levels in the range of 3 to 11% of normal values. CONCLUSIONS: Peripheral-vein infusion of scAAV2/8-LP1-hFIXco resulted in FIX transgene expression at levels sufficient to improve the bleeding phenotype, with few side effects. Although immune-mediated clearance of AAV-transduced hepatocytes remains a concern, this process may be controlled with a short course of glucocorticoids without loss of transgene expression. (Funded by the Medical Research Council and others; ClinicalTrials.gov number, NCT00979238.).


Asunto(s)
Dependovirus , Factor IX/genética , Terapia Genética , Vectores Genéticos , Hemofilia B/terapia , Adulto , Dependovirus/genética , Factor IX/uso terapéutico , Terapia Genética/efectos adversos , Vectores Genéticos/inmunología , Humanos , Infusiones Intravenosas , Persona de Mediana Edad , Transgenes/inmunología
19.
Ann Clin Biochem ; 48(Pt 2): 176-7, 2011 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-21355013

RESUMEN

Selenium is an important clinical biomarker of nutritional status; however, the occurrence of gadolinium in a patient's serum as a result of the contrast agents used during magnetic resonance imaging investigations, results in a significant positive bias in its measurement by inductively coupled plasma-quadrupole mass spectrometry.


Asunto(s)
Artefactos , Análisis Químico de la Sangre/métodos , Gadolinio/sangre , Espectrometría de Masas/métodos , Selenio/sangre , Femenino , Humanos
20.
Chem Res Toxicol ; 23(8): 1313-21, 2010 Aug 16.
Artículo en Inglés | MEDLINE | ID: mdl-20666396

RESUMEN

Platinum-containing drugs are widely used to treat cancer in a variety of clinical settings. Their mode of action involves the formation of DNA adducts, which facilitate apoptosis in cancer cells. Cisplatin binds to the N7 position of the purine DNA bases forming intrastrand cross-links between either two adjacent guanines [cis-Pt(NH(3))(2)d(pGpG), 1,2-GG] or an adjacent adenine and guanine [cis-Pt(NH(3))(2)d(pApG), 1,2-AG)]. The cytotoxic efficacy for each of the different types of DNA adducts and the relationship between adduct levels in tumor cells and blood are not well understood. By using these Pt-containing adduct species as biomarkers, information on a patient's response to chemotherapy would be directly related to the mode of action of the drug. This type of analysis requires the most sensitive and specific methods available, to facilitate detection limits sufficient to measure the DNA adduct in the limited sample quantities available from patients. This was achieved in the current study by coupling a highly specific enzyme-based adduct isolation method with a sensitive detection system based on HPLC coupled to inductively coupled plasma mass spectrometry to measure the 1,2-GG cisplatin adducts formed in DNA. The method was developed and validated using calf thymus DNA and two different adenocarcinoma cell lines. The values for the limit of detection (LOD) and the limit of quantitation determined for the 1,2-GG cisplatin adduct were 0.21 and 0.67 fmol per microg DNA, respectively. This corresponds to an absolute LOD of 0.8 pg as Pt for the 1,2-GG adduct. Cisplatin-sensitive (H23) and -resistant (A549) tumor cells were exposed to the drug, and the 1,2-GG adduct levels were measured over a 24 h time period. The results showed a statistically significant (P < 0.05) higher concentration in the sensitive cells as compared to the resistant cells after repair for 7 h. Although the adduct concentration present fell at subsequent time points (12 and 24 h), the levels in each cell line were broadly similar. The protocol was then applied to the analysis of patient samples taken before and then 1 h after treatment. The 1,2-GG cisplatin adduct was present in the range from 113 to 1245 fg Pt per microg DNA in all of the patient samples taken after treatment. Although the adduct was not present at levels greater than the LOD in the initial pretreatment samples, trace amounts were discernible in some patient samples on their third treatment cycle.


Asunto(s)
Antineoplásicos/análisis , Cisplatino/análisis , Aductos de ADN/análisis , Aductos de ADN/química , Guanina/química , Leucocitos/metabolismo , Animales , Antineoplásicos/química , Antineoplásicos/farmacología , Bovinos , Línea Celular Tumoral , Supervivencia Celular/efectos de los fármacos , Cromatografía Líquida de Alta Presión , Cisplatino/química , Cisplatino/farmacología , ADN/química , ADN/efectos de los fármacos , Aductos de ADN/farmacología , ADN de Neoplasias/efectos de los fármacos , ADN de Neoplasias/genética , Ensayos de Selección de Medicamentos Antitumorales , Humanos , Leucocitos/citología , Leucocitos/efectos de los fármacos , Espectrometría de Masas , Sensibilidad y Especificidad
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