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1.
Front Chem ; 10: 976635, 2022.
Article En | MEDLINE | ID: mdl-36092655

Flerovium (Fl, element 114) is the heaviest element chemically studied so far. To date, its interaction with gold was investigated in two gas-solid chromatography experiments, which reported two different types of interaction, however, each based on the level of a few registered atoms only. Whereas noble-gas-like properties were suggested from the first experiment, the second one pointed at a volatile-metal-like character. Here, we present further experimental data on adsorption studies of Fl on silicon oxide and gold surfaces, accounting for the inhomogeneous nature of the surface, as it was used in the experiment and analyzed as part of the reported studies. We confirm that Fl is highly volatile and the least reactive member of group 14. Our experimental observations suggest that Fl exhibits lower reactivity towards Au than the volatile metal Hg, but higher reactivity than the noble gas Rn.

2.
Eat Weight Disord ; 27(4): 1427-1436, 2022 May.
Article En | MEDLINE | ID: mdl-34370271

OBJECTIVES: Exercise addiction can be secondary to eating disorders, or a primary condition in the absence of another disorder. Currently, to determine secondary exercise addiction, two screening tools must be administered. The aim of this study was to validate a novel screening tool able to stratify between primary and secondary exercise addiction, called the secondary exercise addiction scale (SEAS). METHODS: Phase 1 (n = 339) described the statistical reduction of an initial pool of scale items. Phase 2 (n = 382) used a confirmatory factor analysis (CFA) to examine the robustness of the latent structure. Phase 3 (n = 721) determined cut off scores for the eating disorder and exercise addiction sections of the SEAS and determine concurrent reliability with the exercise addiction inventory (EAI) and the SCOFF questionnaires. Phase 4 (n = 45) determined test-retest reliability. RESULTS: Phase 1 extracted two components: exercise addiction and eating disorder symptomology, with 11 items retained. The CFA in Phase 2 showed an acceptable fit to the proposed model (comparative fit index = 0.93, Tucker Lewis Index = 0.91). Phase 3 determined cut off scores of ≥ 28 (specificity = 91.97%), and ≥ 20 (specificity = 96.27%) in the respective exercise addiction and eating disorders sections of the SEAS. The respective sections also correlated well with the EAI (r = 0.70, p = < 0.001) and the SCOFF (r = 0.72, p = < 0.001). Phase 4 showed excellent test-retest reliability (exercise addiction r = 0.95, p = < 0.001, eating disorders r = 0.93, p = < 0.001). CONCLUSION: The SEAS appears to be a valid and reliable tool for measuring primary and secondary exercise addiction. Further studies are warranted to further validate this tool amongst clinical populations. LEVEL OF EVIDENCE: Level III: evidence obtained from cohort or case-control analytic studies.


Behavior, Addictive , Feeding and Eating Disorders , Behavior, Addictive/diagnosis , Feeding and Eating Disorders/diagnosis , Humans , Psychometrics , Reproducibility of Results , Surveys and Questionnaires
3.
Bone Rep ; 15: 101151, 2021 Dec.
Article En | MEDLINE | ID: mdl-34926730

Two cases of advanced alkaptonuria (AKU) with co-existing osteoporosis are described. Case 1 developed multiple non-vertebral fragility fractures, while Case 2 developed vertebral fragility fractures, both refractory to bisphosphonates. Difficulties in diagnosing osteoporosis in AKU complicated by extensive calcifying and ossifying spondylosis are discussed. Both patients continued to fracture despite nitisinone therapy for metabolic control of AKU, as well as bisphosphonate antiresorptive therapy for osteoporosis. Subsequently the patients were treated with teriparatide 20 µg subcutaneous injections daily for two years, leading to reduction in fractures soon after commencing therapy in both cases. Markers of bone remodelling P1NP and CTX were stimulated. No complications due hypercalcaemia or calcification were encountered in either case. We conclude that teriparatide is an effective adjunct in the treatment of AKU when bisphosphonates prove ineffective.

4.
Front Chem ; 9: 753738, 2021.
Article En | MEDLINE | ID: mdl-34917588

Nihonium (Nh, element 113) and flerovium (Fl, element 114) are the first superheavy elements in which the 7p shell is occupied. High volatility and inertness were predicted for Fl due to the strong relativistic stabilization of the closed 7p 1/2 sub-shell, which originates from a large spin-orbit splitting between the 7p 1/2 and 7p 3/2 orbitals. One unpaired electron in the outermost 7p 1/2 sub-shell in Nh is expected to give rise to a higher chemical reactivity. Theoretical predictions of Nh reactivity are discussed, along with results of the first experimental attempts to study Nh chemistry in the gas phase. The experimental observations verify a higher chemical reactivity of Nh atoms compared to its neighbor Fl and call for the development of advanced setups. First tests of a newly developed detection device miniCOMPACT with highly reactive Fr isotopes assure that effective chemical studies of Nh are within reach.

5.
Phys Rev Lett ; 126(3): 032503, 2021 Jan 22.
Article En | MEDLINE | ID: mdl-33543956

A nuclear spectroscopy experiment was conducted to study α-decay chains stemming from isotopes of flerovium (element Z=114). An upgraded TASISpec decay station was placed behind the gas-filled separator TASCA at the GSI Helmholtzzentrum für Schwerionenforschung in Darmstadt, Germany. The fusion-evaporation reactions ^{48}Ca+^{242}Pu and ^{48}Ca+^{244}Pu provided a total of 32 flerovium-candidate decay chains, of which two and eleven were firmly assigned to ^{286}Fl and ^{288}Fl, respectively. A prompt coincidence between a 9.60(1)-MeV α particle event and a 0.36(1)-MeV conversion electron marked the first observation of an excited state in an even-even isotope of the heaviest man-made elements, namely ^{282}Cn. Spectroscopy of ^{288}Fl decay chains fixed Q_{α}=10.06(1) MeV. In one case, a Q_{α}=9.46(1)-MeV decay from ^{284}Cn into ^{280}Ds was observed, with ^{280}Ds fissioning after only 518 µs. The impact of these findings, aggregated with existing data on decay chains of ^{286,288}Fl, on the size of an anticipated shell gap at proton number Z=114 is discussed in light of predictions from two beyond-mean-field calculations, which take into account triaxial deformation.

6.
Phys Rev Lett ; 125(14): 142504, 2020 Oct 02.
Article En | MEDLINE | ID: mdl-33064498

The electron-capture decay followed by a prompt fission process was searched for in the hitherto unknown most neutron-deficient Md isotope with mass number 244. Alpha decay with α-particle energies of 8.73-8.86 MeV and with a half-life of 0.30_{-0.09}^{+0.19} s was assigned to ^{244}Md. No fission event with a similar half-life potentially originating from spontaneous fissioning of the short-lived electron-capture decay daughter ^{244}Fm was observed, which results in an upper limit of 0.14 for the electron-capture branching of ^{244}Md. Two groups of fission events with half-lives of 0.9_{-0.3}^{+0.6} ms and 5_{-2}^{+3} ms were observed. The 0.9_{-0.3}^{+0.6} ms activity was assigned to originate from the decay of ^{245}Md. The origin of eight fission events resulting in a half-life of 5_{-2}^{+3} ms could not be unambiguously identified within the present data while the possible explanation has to invoke previously unseen physics cases.

7.
AJNR Am J Neuroradiol ; 41(4): 639-644, 2020 04.
Article En | MEDLINE | ID: mdl-32165366

BACKGROUND AND PURPOSE: The increased severity of white matter disease is associated with worse outcomes and an increased rate of intracerebral hemorrhage in patients with ischemic stroke undergoing thrombolytic treatment. However, whether white matter disease is associated with outcomes in patients undergoing endovascular treatment remains unclear. MATERIALS AND METHODS: In this prespecified exploratory analysis of our prospective multi-institutional study that enrolled consecutive adult patients with anterior circulation ischemic stroke undergoing endovascular treatment from November 2017 to September 2018, we compared the following outcomes between patients with none-to-minimal (van Swieten score, 0-2) and moderate-to-severe (van Swieten score, 3-4) white matter disease using logistic regression: 90-day mRS 3-6, death, intracerebral hemorrhage, successful recanalization, and early neurologic recovery. RESULTS: Of the 485 patients enrolled in the Blood Pressure after Endovascular Stroke Therapy (BEST) study, 389 had white matter disease graded (50% women; median age, 68 years; range, 58-79 years). A van Swieten score of 3-4 (n = 74/389, 19%) was associated with a higher rate of 90-day mRS of 3-6 (45% versus 18%; adjusted OR, 2.73; 95% CI, 1.34-5.93; P = .008). Although the death rate was higher in patients with van Swieten scores of 3-4 (26% versus 15%), the adjusted likelihood was not significantly different (adjusted OR, 1.14; 95% CI, 0.56-2.26; P = .710). Ordered regression revealed a shift toward worse mRS scores with increasing van Swieten scores (adjusted common OR, 3.04; 95% CI, 1.93-4.84; P < .001). No associations between white matter disease severity and intracerebral hemorrhage, successful recanalization, and early neurologic recovery were observed. CONCLUSIONS: Moderate-to-severe white matter disease is associated with worse outcomes in patients undergoing endovascular treatment without a significant increase in hemorrhagic complications. Studies comparing patients with and without endovascular treatment are necessary to determine whether the benefit of endovascular treatment is attenuated with greater white matter disease.


Leukoencephalopathies/complications , Stroke/complications , Stroke/surgery , Thrombectomy/methods , Treatment Outcome , Aged , Brain Ischemia/complications , Endovascular Procedures/methods , Female , Humans , Male , Middle Aged , Prospective Studies
8.
Rev Neurol ; 68(2): 75-81, 2019 Jan 16.
Article Es, En | MEDLINE | ID: mdl-30638257

INTRODUCTION: Dravet syndrome (DS) is a rare, drug resistant epilepsy that starts very early in life with febrile seizures followed by cognitive impairment and diverse seizure types. AIM: To generate evidence on the epidemiology of DS, its diagnosis, patient-flow, treatment and unmet needs from the perspective of Spanish experts. DEVELOPMENT: A two-round Delphi study involving 19 physicians was conducted. Questionnaires were based on literature review and validated by clinical experts. Consensus was reached when topics were subject to routine clinical practice and individual experience, or the coefficient of variation among answers was <= 0.3. The estimated number of new DS patients is 73 per year. Prevalence is estimated to be between 348-540 patients. DS is mostly diagnosed in children. Survival varies from 5 to 60 years. There is no standardised follow-up of patients beyond the age of 18 and mortality rates are uncertain. No standard guidelines exist for diagnosing or treating DS. It takes 9 to 15 months to confirm the diagnosis and genetic testing is unevenly available. Valproic acid, clobazam, stiripentol and topiramate are commonly used. Poor efficacy and safety are the main reasons for treatment switch. CONCLUSIONS: The epidemiology of DS in Spain is not well known and several areas of unmet needs still exist. Experts' views offer a starting point for further research into the reality of DS in Spain. Epidemiological studies, consensus criteria, easy access to genetic testing, treatment options, training and research into quality of life aspects are highly needed.


TITLE: Determinacion de la epidemiologia, el flujo de pacientes y el tratamiento del sindrome de Dravet en España.Introduccion. El sindrome de Dravet (SD) es una epilepsia rara y resistente a los farmacos que comienza en etapas muy precoces de la vida con convulsiones febriles, seguidas de deterioro cognitivo y diversos tipos de crisis epilepticas. Objetivo. Generar datos objetivos sobre la epidemiologia del SD, su diagnostico, el flujo de pacientes, el tratamiento y las necesidades no cubiertas desde el punto de vista de expertos españoles. Desarrollo. Se efectuo un estudio Delphi de dos rondas en el que participaron 19 medicos. Los cuestionarios se basaron en una revision de la bibliografia y fueron validados por expertos clinicos. Se alcanzo consenso si los temas se referian a la practica clinica habitual y la experiencia individual, o si el coeficiente de variacion entre las respuestas era <= 0,3. El numero estimado de pacientes nuevos con SD es de 73 al año. La prevalencia se calcula entre 348 y 540 pacientes. El SD se diagnostica principalmente en niños. La supervivencia varia entre los 5 y los 60 años. No existe ningun seguimiento normalizado para los pacientes de mas de 18 años de edad, y las tasas de mortalidad son inciertas. No existen guias normalizadas para diagnosticar o tratar el SD. Se tarda de 9 a 15 meses en confirmar el diagnostico, y la disponibilidad de los analisis geneticos es irregular. Normalmente se utilizan el acido valproico, el clobazam, el estiripentol y el topiramato. La escasa eficacia y la seguridad son los motivos principales de los cambios de tratamiento. Conclusiones. La epidemiologia del SD en España es poco conocida, y sigue habiendo necesidades no cubiertas en algunas areas. Las opiniones de expertos suponen un punto de partida para poder investigar la realidad del SD en España. Los estudios epidemiologicos, los criterios de consenso, el acceso facil a las pruebas geneticas, las opciones de tratamiento, la formacion y la investigacion de la calidad de vida relacionada con la salud constituyen todos ellos aspectos muy necesarios.


Epilepsies, Myoclonic/epidemiology , Adult , Age of Onset , Anticonvulsants/therapeutic use , Child , Child, Preschool , Consensus , Continuity of Patient Care , Delphi Technique , Disease Management , Disease Progression , Drug Resistance , Epilepsies, Myoclonic/drug therapy , Epilepsies, Myoclonic/genetics , Humans , Infant , Prevalence , Referral and Consultation , Spain/epidemiology , Sudden Infant Death/etiology
9.
Phys Rev Lett ; 120(26): 263003, 2018 Jun 29.
Article En | MEDLINE | ID: mdl-30004781

One of the most important atomic properties governing an element's chemical behavior is the energy required to remove its least-bound electron, referred to as the first ionization potential. For the heaviest elements, this fundamental quantity is strongly influenced by relativistic effects which lead to unique chemical properties. Laser spectroscopy on an atom-at-a-time scale was developed and applied to probe the optical spectrum of neutral nobelium near the ionization threshold. The first ionization potential of nobelium is determined here with a very high precision from the convergence of measured Rydberg series to be 6.626 21±0.000 05 eV. This work provides a stringent benchmark for state-of-the-art many-body atomic modeling that considers relativistic and quantum electrodynamic effects and paves the way for high-precision measurements of atomic properties of elements only available from heavy-ion accelerator facilities.

10.
Phys Rev Lett ; 120(23): 232503, 2018 Jun 08.
Article En | MEDLINE | ID: mdl-29932712

Until recently, ground-state nuclear moments of the heaviest nuclei could only be inferred from nuclear spectroscopy, where model assumptions are required. Laser spectroscopy in combination with modern atomic structure calculations is now able to probe these moments directly, in a comprehensive and nuclear-model-independent way. Here we report on unique access to the differential mean-square charge radii of ^{252,253,254}No, and therefore to changes in nuclear size and shape. State-of-the-art nuclear density functional calculations describe well the changes in nuclear charge radii in the region of the heavy actinides, indicating an appreciable central depression in the deformed proton density distribution in ^{252,254}No isotopes. Finally, the hyperfine splitting of ^{253}No was evaluated, enabling a complementary measure of its (quadrupole) deformation, as well as an insight into the neutron single-particle wave function via the nuclear spin and magnetic moment.

12.
Phys Rev Lett ; 115(24): 242502, 2015 Dec 11.
Article En | MEDLINE | ID: mdl-26705628

Two short-lived isotopes ^{221}U and ^{222}U were produced as evaporation residues in the fusion reaction ^{50}Ti+^{176}Yb at the gas-filled recoil separator TASCA. An α decay with an energy of E_{α}=9.31(5) MeV and half-life T_{1/2}=4.7(7) µs was attributed to ^{222}U. The new isotope ^{221}U was identified in α-decay chains starting with E_{α}=9.71(5) MeV and T_{1/2}=0.66(14) µs leading to known daughters. Synthesis and detection of these unstable heavy nuclei and their descendants were achieved thanks to a fast data readout system. The evolution of the N=126 shell closure and its influence on the stability of uranium isotopes are discussed within the framework of α-decay reduced width.

13.
Phys Rev Lett ; 112(17): 172501, 2014 May 02.
Article En | MEDLINE | ID: mdl-24836239

The superheavy element with atomic number Z=117 was produced as an evaporation residue in the (48)Ca+(249)Bk fusion reaction at the gas-filled recoil separator TASCA at GSI Darmstadt, Germany. The radioactive decay of evaporation residues and their α-decay products was studied using a detection setup that allowed measuring decays of single atomic nuclei with half-lives between sub-µs and a few days. Two decay chains comprising seven α decays and a spontaneous fission each were identified and are assigned to the isotope (294)117 and its decay products. A hitherto unknown α-decay branch in (270)Db (Z = 105) was observed, which populated the new isotope (266)Lr (Z = 103). The identification of the long-lived (T(1/2) = 1.0(-0.4)(+1.9) h) α-emitter (270)Db marks an important step towards the observation of even more long-lived nuclei of superheavy elements located on an "island of stability."

14.
Phys Rev Lett ; 111(11): 112502, 2013 Sep 13.
Article En | MEDLINE | ID: mdl-24074079

A high-resolution α, x-ray, and γ-ray coincidence spectroscopy experiment was conducted at the GSI Helmholtzzentrum für Schwerionenforschung. Thirty correlated α-decay chains were detected following the fusion-evaporation reaction 48Ca + 243Am. The observations are consistent with previous assignments of similar decay chains to originate from element Z=115. For the first time, precise spectroscopy allows the derivation of excitation schemes of isotopes along the decay chains starting with elements Z>112. Comprehensive Monte Carlo simulations accompany the data analysis. Nuclear structure models provide a first level interpretation.

15.
Mediterr J Hematol Infect Dis ; 3(1): e2011045, 2011.
Article En | MEDLINE | ID: mdl-22110895

Balanced chromosomal translocations that generate chimeric oncoproteins are considered to be initiating lesions in the pathogenesis of acute myeloid leukemia. The most frequent is the t(15;17)(q22;q21), which fuses the PML and RARA genes, giving rise to acute promyelocytic leukemia (APL). An increasing proportion of APL cases are therapy-related (t-APL), which develop following exposure to radiotherapy and/or chemotherapeutic agents that target DNA topoisomerase II (topoII), particularly mitoxantrone and epirubicin. To gain insights into molecular mechanisms underlying the formation of the t(15;17) we mapped the translocation breakpoints in a series of t-APLs, which revealed significant clustering according to the nature of the drug exposure. Remarkably, in approximately half of t-APL cases arising following mitoxantrone treatment for breast cancer or multiple sclerosis, the chromosome 15 breakpoint fell within an 8-bp "hotspot" region in PML intron 6, which was confirmed to be a preferential site of topoII-mediated DNA cleavage induced by mitoxantrone. Chromosome 15 breakpoints falling outside the "hotspot", and the corresponding RARA breakpoints were also shown to be functional topoII cleavage sites. The observation that particular regions of the PML and RARA loci are susceptible to topoII-mediated DNA damage induced by epirubicin and mitoxantrone may underlie the propensity of these agents to cause APL.

16.
Clin Radiol ; 66(6): 540-5, 2011 Jun.
Article En | MEDLINE | ID: mdl-21458784

AIMS: To define and compare magnetic resonance imaging (MRI) findings of asymptomatic patients with metal-on-metal (MOM) and polyethylene-on-metal (POM) total hip replacements (THRs). MATERIALS AND METHODS: Twenty-two THRs in 20 asymptomatic patients (seven men, 13 women, mean age 68 years, range 47-86 years) with normal hip radiographs were included in the study. These comprised 10 POM and 12 MOM bearings. Each patient underwent MRI with metal artefact reduction sequences (MARS) at a mean time of 46 months (POM) and 70 months (MOM) after surgery. Two musculoskeletal radiologists independently read each MRI examination for fluid collections, soft-tissue masses, muscle atrophy, and bone marrow signal changes. RESULTS: A pre-MRI hip radiograph showed no significant differences from the postoperative radiograph regarding acetabular inclination, femoral stem angle, and stem mantle grade. There were eight periprosthetic collections (one POM, seven MOM). The majority of THRs had normal gluteal muscles. The ipsilateral piriformis and obturator internus muscles were more frequently abnormal in the MOM group. Overall, there were no significant differences in the number of abnormalities between the two types of bearings. CONCLUSION: A range of MRI abnormalities are present in normal asymptomatic THRs but the increased frequency of these associated with MOM THR suggest that some of these changes might represent subclinical disease.


Arthroplasty, Replacement, Hip/instrumentation , Metals , Osteoarthritis, Hip/diagnosis , Polyethylene , Aged , Aged, 80 and over , Bone Density/physiology , Epidemiologic Methods , Female , Humans , Magnetic Resonance Imaging , Male , Middle Aged , Osteoarthritis, Hip/physiopathology , Osteoarthritis, Hip/surgery
17.
JRSM Short Rep ; 1(4): 30, 2010 Sep 15.
Article En | MEDLINE | ID: mdl-21103122

OBJECTIVES: Providing information to cancer patients can have significant benefits to their psychological wellbeing. The aim of this study was to investigate whether and how information needs may differ for patients at different stages of the cancer journey. DESIGN: Cross-sectional, self-completed survey using convenience sampling. SETTING: Oncology outpatients in Wolverhampton, West Midlands. PARTICIPANTS: Cancer patients aged 18 years and over. MAIN OUTCOME MEASURES: The survey used Likert scales to determine whether patients wished to know more about 35 items of information categorized under seven domains: cancer (diagnosis); prognosis; treatment; rehabilitation; psychological/spiritual; social/family; and body image/sexuality. Each domain was scored, with higher scores indicating a greater wish for information. RESULTS: There were 187 participants (50% response rate). Patients tended to want more information, particularly related to prognosis. Post-treatment patients continued to have information needs comparable to patients undergoing treatment or at the pre-treatment stage, except with reference to treatment-related information (p = <0.01), although as time from diagnosis increased, information needs reduced. Educational attainment, age, treatment status, gender and ethnicity were all significant predictors of scores in various domains. CONCLUSION: This study indicates that the time since diagnosis may interact with various demographic and disease-related factors in contributing to the information needs of cancer patients. The majority of cancer patients wish to know more about a wide range of factors, and such information seeking preferences are present regardless of an individual's stage following diagnosis.

18.
J Biomed Mater Res A ; 83(4): 940-953, 2007 Dec 15.
Article En | MEDLINE | ID: mdl-17580323

In this work, we evaluated the in vitro cytotoxicity and in vivo biocompatibility of a novel poly(propylene fumarate) (PPF)-based/alumoxane nanocomposite for bone tissue engineering applications. The incorporation of functionalized alumoxane nanoparticles into the PPF-based polymer was previously shown to significantly increase the material's flexural mechanical properties. In the current study, samples underwent accelerated in vitro degradation to allow the study of biological responses to these materials over the course of their degradation on a shortened timescale. The polymer, a macrocomposite composed of the polymer and micron-sized particles, and the nanocomposite were evaluated at three stages of degradation for in vitro cytotoxicity with a fibroblast cell line and in vivo soft-tissue response after 3 and 12 weeks of implantation in adult goats. All three material groups experienced mass loss during degradation, but the nanocomposite group eroded significantly faster than the other groups. Nondegraded materials demonstrated minimal cytotoxicity and a minor inflammatory response in soft tissue. On the contrary, predegraded samples elicited more pronounced responses, though these were due to the increase in surface area, surface roughness, and fragmentation associated with the degradation process. The presence of alumoxane nanoparticles in the PPF-based nanocomposite did not significantly affect its cytotoxicity or biocompatibility.


Aluminum Compounds/chemistry , Biocompatible Materials , Fumarates/chemistry , Nanocomposites , Polypropylenes/chemistry , Tissue Engineering , Animals , Cell Line , Female , Goats , Rats
19.
Gene Ther ; 13(2): 117-26, 2006 Jan.
Article En | MEDLINE | ID: mdl-16163377

Immune responses against an introduced transgenic protein are a potential risk in many gene replacement strategies to treat genetic disease. We have developed a gene delivery approach for hemophilia B based on lentiviral expression of human factor IX in purified hematopoietic stem cells. In both normal C57Bl/6J and hemophilic 129/Sv recipient mice, we observed the production of therapeutic levels of human factor IX, persisting for at least a year with tolerance to human factor IX antigen. Secondary and tertiary recipients also demonstrate long-term production of therapeutic levels of human factor IX and tolerance, even at very low levels of donor chimerism. Furthermore, in hemophilic mice, partial functional correction of treated mice and phenotypic rescue is achieved. These data show the potential of a stem cell approach to gene delivery to tolerize recipients to a secreted foreign transgenic protein and, with appropriate modification, may be of use in developing treatments for other genetic disorders.


Factor IX/genetics , Genetic Therapy/methods , HIV-1/genetics , Hemophilia B/therapy , Stem Cell Transplantation/methods , Animals , Antigens/immunology , Cells, Cultured , Factor IX/metabolism , Gene Expression , Genetic Diseases, Inborn/genetics , Genetic Diseases, Inborn/therapy , Genotype , Green Fluorescent Proteins/genetics , Hemophilia B/blood , Humans , Immune Tolerance , Mice , Mice, Inbred C57BL , Phenotype , Stem Cells/metabolism , Stem Cells/virology , Time Factors , Transduction, Genetic/methods , Transgenes
20.
Ecotoxicology ; 14(4): 465-75, 2005 May.
Article En | MEDLINE | ID: mdl-16385740

Metal (Al, As, Ca, Cd, Cu, Fe, K, Mg, Mn, Na, Pb, Zn) levels in the feeding organ or radula of the common limpet Patella vulgata L. were surveyed in 10 populations over a approximately 150-km stretch of coastline in north-east England. The most northern population was at Beadnell in Northumberland and the most southern was at Port Mulgrave in North Yorkshire; sites included unspoilt bays and areas heavily affected by industrial contamination such as the River Tees estuary. We hypothesized that the radula might be used as an indicator of environmental contamination. There were significant differences between the sites in the ratio of radula length to shell length. Limpets from Whitburn had the smallest radula fraction (mean = 1.665), while those from Port Mulgrave the largest (mean = 1.998). Such variation is common in the literature and we detected no correlate and propose no cause. Iron was clearly the dominant metal in the radulae, with an overall of mean of 1.46% of radular weight, though this is rather low in comparison to values in the literature. Iron is naturally secreted into the developing radula as a putative hardening agent. The next most abundant metals, in descending order, were Na (at approximately 2000-8000 microg g(-1)), K, Mg, Ca (approximately 1000-1500 microg g(-1)), Zn, Cu, Al, Pb (approximately 7-75 microg g(-1)), Mn, As, Cd (approximately 0-1 microg g(-1)). All but Al and Cd showed significant differences between the sites, but not in any consistent or convincing geographic manner. Nevertheless, the variations in metal levels between sites (e.g. Fe > 72%, Cu and Zn > 10-fold) suggest an environmental cause, but we are unable to offer any responsible factor, for example, there appeared little effect of the River Tees estuary. Cadmium is at a relatively low level in the radula in comparison to published data on pedal mucus and the flesh, but Pb is relatively high in pedal mucus and the radula and this might suggest that the radula is a detoxification route for Pb. Although the relationship between radula metal content and environmental metal content is unknown, the radula is constantly replaced and so may yet have the potential to be of use as a bioindicator, integrating metal exposure over much shorter periods than whole body burdens.


Gastropoda , Metals, Heavy/analysis , Water Pollutants/analysis , Animals , Environmental Monitoring , Feeding Behavior , Metals, Heavy/pharmacokinetics , Tissue Distribution , United Kingdom , Water Pollutants/pharmacokinetics
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