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1.
Philos Trans A Math Phys Eng Sci ; 382(2280): 20230410, 2024 Oct 09.
Article in English | MEDLINE | ID: mdl-39183651

ABSTRACT

Ensuring tritium fuel self-sufficiency while maintaining continuous and high-specification fuel flow to the tokamak via a low tritium inventory and controllable fuel cycle is a significant challenge to the STEP plant design. Effective and high-quality fuelling and exhaust design is required to sustain and control a stable plasma, whereas fuel sufficiency is required to prevent depletion of available tritium supply. Concerns regarding the lack of tritium availability preventing continuous tritium import are countered by breeding, where highly energetic neutrons from the core fusion reactions interact with lithium atoms suspended in the surrounding breeder blanket to produce tritium. The compact nature of STEP prohibits the integration of inboard breeder blankets posing a significant challenge for the design team looking to ensure more tritium is bred and made available than consumed within the core plasma. This paper outlines how purposeful technology selection and system architecting has converged on the outline of a conceivable and tritium-capable fuel cycle and breeder blanket design. Before introducing the STEP fuel cycle design outline and summarizing the approach undertaken to address the challenges facing plasma fuelling, key aspects of fuel self-sufficiency are discussed. This includes discussing a proposed helium-cooled liquid lithium breeder blanket and possible technology options for tritium extraction from lithium. Lastly, there is a brief process modelling overview, which emphasizes the central contribution of various employed modelling methods. Reflections on the presented fuel cycle design outline conclude that substantial development work is still required to realize a continuous tritium fuel cycle design and overcome the major challenges posed by tritium and lithium handling. Reflections on the presented breeder blanket design proposal conclude that while many substantial risks and blockers remain to achieve fuel self-sufficiency, high breeding ratios are expected to be achievable with a compact spherical tokamak configuration. Nonetheless, it is recognized that further consideration is required to ensure that the selection of liquid lithium as a breeder medium provides the overall simplest route to a self-sufficient and realizable design.This article is part of the theme issue 'Delivering Fusion Energy - The Spherical Tokamak for Energy Production (STEP)'.

2.
Clin Chem Lab Med ; 2024 Jul 30.
Article in English | MEDLINE | ID: mdl-39072400

ABSTRACT

OBJECTIVES: Assessment of Wilson disease is complicated, with neither ceruloplasmin, nor serum or urine copper, being reliable. Two new indices, accurate non-ceruloplasmin copper (ANCC) and relative ANCC were developed and applied to a cohort of 71 patients, as part of a Wilson Disease Registry Study. METHODS: Elemental copper-protein speciation was developed for holo-ceruloplasmin quantitation using strong anion exchange chromatography coupled to triple quadrupole inductively coupled plasma mass spectrometry. The serum proteins were separated using gradient elution and measured at m/z 63 (63Cu+) and 48 (32S16O+) using oxygen reaction mode and Cu-EDTA as calibration standard. The ANCC was calculated by subtraction of the ceruloplasmin bound copper from the total serum copper and the RelANCC was the percentage of total copper present as the ANCC. RESULTS: The accuracy of the holo-ceruloplasmin measurement was established using two certified reference materials, giving a mean recovery of 94.2 %. Regression analysis between the sum of the copper containing species and total copper concentration in the patient samples was acceptable (slope=0.964, intercept=0, r=0.987) and a difference plot, gave a mean difference for copper of 0.38 µmol/L. Intra-day precision for holo-ceruloplasmin at serum copper concentrations of 0.48 and 3.20 µmol/L were 5.2 and 5.6 % CV and the intermediate precision at concentrations of 0.80 and 5.99 µmol/L were 6.4 and 6.4 % CV, respectively. The limit of detection (LOD) and lower limit of quantification (LLOQ) for holo-ceruloplasmin were 0.08 and 0.27 µmol/L as copper, respectively. CONCLUSIONS: ANCC and Relative ANCC are important new diagnostic and monitoring biomarker indices for Wilson disease (WD).

3.
Heart ; 109(15): 1175-1182, 2023 07 12.
Article in English | MEDLINE | ID: mdl-37137675

ABSTRACT

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.


Subject(s)
Cardiomyopathy, Hypertrophic , Trientine , Humans , Trientine/therapeutic use , Copper/therapeutic use , Cardiomyopathy, Hypertrophic/diagnosis , Cardiomyopathy, Hypertrophic/drug therapy , Cardiomyopathy, Hypertrophic/complications , Heart , Hypertrophy, Left Ventricular/drug therapy , Hypertrophy, Left Ventricular/etiology , Hypertrophy, Left Ventricular/prevention & control , Fibrosis
4.
Crit Rev Anal Chem ; : 1-18, 2023 Jan 13.
Article in English | MEDLINE | ID: mdl-36637361

ABSTRACT

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.

5.
Maedica (Bucur) ; 16(2): 207-210, 2021 Jun.
Article in English | MEDLINE | ID: mdl-34621341

ABSTRACT

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.

6.
Haemophilia ; 27(3): 425-433, 2021 May.
Article in English | MEDLINE | ID: mdl-33749973

ABSTRACT

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.


Subject(s)
Atrial Fibrillation , Cardiovascular Diseases , Coronary Artery Disease , Drug-Eluting Stents , Percutaneous Coronary Intervention , Anticoagulants/therapeutic use , Atrial Fibrillation/drug therapy , Drug Therapy, Combination , Fibrinolytic Agents/therapeutic use , Humans , Platelet Aggregation Inhibitors/therapeutic use
7.
Anal Chim Acta ; 1098: 27-36, 2020 Feb 15.
Article in English | MEDLINE | ID: mdl-31948584

ABSTRACT

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.


Subject(s)
Biomedical Research , Copper/blood , Hepatolenticular Degeneration/blood , Chromatography, Ion Exchange/instrumentation , Hepatolenticular Degeneration/diagnosis , Humans , Mass Spectrometry/instrumentation
8.
World J Gastrointest Endosc ; 10(1): 37-44, 2018 Jan 16.
Article in English | MEDLINE | ID: mdl-29375740

ABSTRACT

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.

9.
Ann Clin Biochem ; 54(3): 362-369, 2017 May.
Article in English | MEDLINE | ID: mdl-27422134

ABSTRACT

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.


Subject(s)
Arthroplasty, Replacement, Hip , Spectrophotometry, Atomic/standards , Titanium/blood , Chromium/blood , Cobalt/blood , Female , Hip Prosthesis , Humans , Limit of Detection , Male , Quality Control , Reference Standards
11.
Clin Chem Lab Med ; 54(12): 1921-1928, 2016 Dec 01.
Article in English | MEDLINE | ID: mdl-27174868

ABSTRACT

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.


Subject(s)
Clinical Laboratory Techniques/standards , Manganese/blood , Manganese/urine , Humans
12.
Ann Surg Oncol ; 23(2): 573-8, 2016 Feb.
Article in English | MEDLINE | ID: mdl-26286197

ABSTRACT

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.


Subject(s)
Carcinoma, Merkel Cell/radiotherapy , Carcinoma, Merkel Cell/surgery , Neoplasm Recurrence, Local/radiotherapy , Neoplasm Recurrence, Local/surgery , Skin Neoplasms/radiotherapy , Skin Neoplasms/surgery , Adult , Aged , Aged, 80 and over , British Columbia , Carcinoma, Merkel Cell/pathology , Combined Modality Therapy , Disease Management , Female , Follow-Up Studies , Humans , Male , Middle Aged , Neoplasm Recurrence, Local/pathology , Neoplasm Staging , Prognosis , Radiotherapy, Adjuvant , Retrospective Studies , Skin Neoplasms/pathology , Survival Rate
13.
Anal Bioanal Chem ; 407(16): 4541-54, 2015 Jun.
Article in English | MEDLINE | ID: mdl-25874977

ABSTRACT

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.


Subject(s)
Arthroplasty, Replacement, Hip , Body Fluids/chemistry , Fractionation, Field Flow , Metalloproteins/analysis , Metals/analysis , Feasibility Studies , Humans , Mass Spectrometry
14.
J Pharm Biomed Anal ; 106: 210-7, 2015 Mar 15.
Article in English | MEDLINE | ID: mdl-25455724

ABSTRACT

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.


Subject(s)
Antineoplastic Agents/analysis , Arsenicals/analysis , Cisplatin/analysis , Glutathione/analogs & derivatives , Animals , Chromatography, Liquid/methods , Glutathione/analysis , Humans , Mass Spectrometry/methods , Spectrophotometry, Atomic/methods
15.
Ann Surg Oncol ; 21(11): 3401-5, 2014 Oct.
Article in English | MEDLINE | ID: mdl-25001091

ABSTRACT

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.


Subject(s)
Carcinoma, Merkel Cell/radiotherapy , Carcinoma, Merkel Cell/surgery , Radiotherapy , Skin Neoplasms/radiotherapy , Skin Neoplasms/surgery , Adult , Aged , Aged, 80 and over , Carcinoma, Merkel Cell/mortality , Carcinoma, Merkel Cell/pathology , Combined Modality Therapy , Female , Follow-Up Studies , Humans , Male , Middle Aged , Neoplasm Staging , Prognosis , Retrospective Studies , Skin Neoplasms/mortality , Skin Neoplasms/pathology , Survival Rate
16.
BMJ Case Rep ; 20142014 Jul 08.
Article in English | MEDLINE | ID: mdl-25006053

ABSTRACT

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.


Subject(s)
Capsule Endoscopes , Crohn Disease/diagnosis , Foreign Bodies/diagnostic imaging , Ileum/diagnostic imaging , Adolescent , Capsule Endoscopy , Humans , Male , Radiography , Thinness , Young Adult
17.
Ann Clin Biochem ; 51(Pt 3): 386-91, 2014 May.
Article in English | MEDLINE | ID: mdl-24081185

ABSTRACT

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.


Subject(s)
Blood Chemical Analysis/methods , Gadolinium/blood , Mass Spectrometry/methods , Selenium/blood , Artifacts , Gadolinium/chemistry , Hospitals , Humans
18.
J Toxicol Environ Health A ; 75(13-15): 893-908, 2012.
Article in English | MEDLINE | ID: mdl-22788375

ABSTRACT

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.


Subject(s)
Environmental Exposure , Immunosuppressive Agents/metabolism , Metalloids/metabolism , Metals, Heavy/metabolism , Mining , Mutagens/metabolism , Occupational Exposure , Aged , Arsenic/administration & dosage , Arsenic/blood , Arsenic/metabolism , Arsenic/urine , Biomarkers/blood , Biomarkers/metabolism , Biomarkers/urine , Female , Genes, T-Cell Receptor/drug effects , Hair/metabolism , Heavy Metal Poisoning , Humans , Immunosuppressive Agents/administration & dosage , Immunosuppressive Agents/blood , Immunosuppressive Agents/urine , Lymphocyte Subsets/drug effects , Male , Metalloids/administration & dosage , Metalloids/blood , Metalloids/urine , Metals, Heavy/administration & dosage , Metals, Heavy/blood , Metals, Heavy/urine , Middle Aged , Mutagens/administration & dosage , Mutation/drug effects , Nails/metabolism , Poisoning/blood , Poisoning/etiology , Poisoning/metabolism , Poisoning/urine , Portugal/epidemiology , Selenium/administration & dosage , Selenium/blood , Selenium/metabolism , Selenium/urine
20.
N Engl J Med ; 365(25): 2357-65, 2011 Dec 22.
Article in English | MEDLINE | ID: mdl-22149959

ABSTRACT

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.).


Subject(s)
Dependovirus , Factor IX/genetics , Genetic Therapy , Genetic Vectors , Hemophilia B/therapy , Adult , Dependovirus/genetics , Factor IX/therapeutic use , Genetic Therapy/adverse effects , Genetic Vectors/immunology , Humans , Infusions, Intravenous , Middle Aged , Transgenes/immunology
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