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1.
Nature ; 581(7809): 396-400, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-32461650

RESUMO

Molecular spectroscopy offers opportunities for the exploration of the fundamental laws of nature and the search for new particle physics beyond the standard model1-4. Radioactive molecules-in which one or more of the atoms possesses a radioactive nucleus-can contain heavy and deformed nuclei, offering high sensitivity for investigating parity- and time-reversal-violation effects5,6. Radium monofluoride, RaF, is of particular interest because it is predicted to have an electronic structure appropriate for laser cooling6, thus paving the way for its use in high-precision spectroscopic studies. Furthermore, the effects of symmetry-violating nuclear moments are strongly enhanced5,7-9 in molecules containing octupole-deformed radium isotopes10,11. However, the study of RaF has been impeded by the lack of stable isotopes of radium. Here we present an experimental approach to studying short-lived radioactive molecules, which allows us to measure molecules with lifetimes of just tens of milliseconds. Energetically low-lying electronic states were measured for different isotopically pure RaF molecules using collinear resonance ionisation at the ISOLDE ion-beam facility at CERN. Our results provide evidence of the existence of a suitable laser-cooling scheme for these molecules and represent a key step towards high-precision studies in these systems. Our findings will enable further studies of short-lived radioactive molecules for fundamental physics research.

2.
Phys Rev Lett ; 127(3): 033001, 2021 Jul 16.
Artigo em Inglês | MEDLINE | ID: mdl-34328758

RESUMO

Isotope shifts of ^{223-226,228}Ra^{19}F were measured for different vibrational levels in the electronic transition A^{2}Π_{1/2}←X^{2}Σ^{+}. The observed isotope shifts demonstrate the particularly high sensitivity of radium monofluoride to nuclear size effects, offering a stringent test of models describing the electronic density within the radium nucleus. Ab initio quantum chemical calculations are in excellent agreement with experimental observations. These results highlight some of the unique opportunities that short-lived molecules could offer in nuclear structure and in fundamental symmetry studies.

3.
Phys Rev Lett ; 126(3): 032502, 2021 Jan 22.
Artigo em Inglês | MEDLINE | ID: mdl-33543945

RESUMO

The mean-square charge radii of ^{207,208}Hg (Z=80, N=127, 128) have been studied for the first time and those of ^{202,203,206}Hg (N=122, 123, 126) remeasured by the application of in-source resonance-ionization laser spectroscopy at ISOLDE (CERN). The characteristic kink in the charge radii at the N=126 neutron shell closure has been revealed, providing the first information on its behavior below the Z=82 proton shell closure. A theoretical analysis has been performed within relativistic Hartree-Bogoliubov and nonrelativistic Hartree-Fock-Bogoliubov approaches, considering both the new mercury results and existing lead data. Contrary to previous interpretations, it is demonstrated that both the kink at N=126 and the odd-even staggering (OES) in its vicinity can be described predominately at the mean-field level and that pairing does not need to play a crucial role in their origin. A new OES mechanism is suggested, related to the staggering in the occupation of the different neutron orbitals in odd- and even-A nuclei, facilitated by particle-vibration coupling for odd-A nuclei.

4.
Unfallchirurg ; 124(12): 1000-1006, 2021 Dec.
Artigo em Alemão | MEDLINE | ID: mdl-33665719

RESUMO

BACKGROUND: For years e­bike (Pedelec) sales have been steadily increasing. Therefore, the incidence of e­bike-related injuries and deaths has been growing. Due to clinical experience, emergency personnel are suspecting that e­bikers might be injured more severely compared to conventional bicyclists suffering from an accident. This topic has not yet been analyzed for Germany. OBJECTIVE: Analysis of injury severity and mortality following e­bike and conventional bicycle accidents in a level I trauma center in Germany. MATERIAL AND METHODS: Data of patients treated after a bicycle accident at the accident and emergency department as well as the clinic for traumatology and orthopedics of the Evangelical Hospital (Evangelisches Krankenhaus) Oldenburg were gathered from 1 March 2017 to 1 March 2019. RESULTS: In this study 59 electric bicycle users (e-bikers) and 164 conventional cyclists were included. The average age of e­bikers was 62 years compared to 48 years in the group of conventional cyclists. Comorbidities were significantly more frequent in the e­bike group compared to classical cyclists. The e­bikers were found to be significantly more severely injured than conventional bicyclists, the mean injury severity scores (ISS) were 5.2 and 3.4, respectively. E­bikers were admitted to the hospital more often and for longer periods than the control group. There was no significant difference in mortality. CONCLUSION: E­bikers are more severely injured in accidents compared to conventional cyclists. Due to older age and comorbidity they form a sensitive trauma subgroup. Based on demographics, an increase of old age, more frail cyclists and a growing incidence of serious e­bike accidents is to be expected. Preventive measures, such as helmet usage and riding lessons should be introduced, especially in e­bikers. E­bikers in the emergency department should be examined and treated with special care and aggressive diagnostics. A low threshold for an initial interdisciplinary assessment (shock room management) is advised.


Assuntos
Acidentes de Trânsito , Ciclismo , Idoso , Alemanha/epidemiologia , Dispositivos de Proteção da Cabeça , Humanos , Incidência , Escala de Gravidade do Ferimento , Pessoa de Meia-Idade
5.
Arch Orthop Trauma Surg ; 139(9): 1225-1233, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-30976900

RESUMO

BACKGROUND: Pelvic ring injuries are serious injuries, often associated with substantial morbidity and mortality rates. The long-term consequences of these injuries might affect the patients' personal life. Our aim was to assess the long-term effects of pelvic ring injuries on physical functioning and quality of life (QoL) using validated patient-reported outcome measures (PROMs) and comparing these results to normative data from the general population. PATIENTS AND METHODS: A retrospective cohort study was conducted on adults treated for pelvic ring injuries between 2007 and 2016. Demographics, fracture type, injury mechanism, treatment and complications were recorded. PROMs questionnaires concerning physical functioning (SMFA) and quality of life (EQ-5D) were used. Patients were divided according to their age (18-30, 31-64, 65 and older) and fracture type (Tile/AO type A, B or C). Differences in SMFA and EQ-5D scores of the operatively and non-operatively treated patients and between the study population and general population were analyzed. RESULTS: A total of 413 patients were identified of which 279 were eligible for follow-up. One-hundred and ninety-two (69%) patients responded with a mean follow-up of 4.4 years. Patients reported a median score of 13.9 on the SMFA function index, 16.7 on the bother index, 12.5 on the lower extremity, 18.8 on the activities of daily living and 23.4 on the emotion subscale. A median EQ-5D score of 0.8 was reported. There was no difference in physical functioning and QoL between operatively and non-operatively treated patients. Comparison of these results to normative data of the general population revealed a significant (P < 0.05) decrease in physical functioning and QoL in patients with all types of pelvic ring injuries. CONCLUSION: Long-term physical functioning and QoL in patients who had sustained a pelvic ring injury seems fair, although significantly decreased in comparison with their peers from the general population.


Assuntos
Fraturas Ósseas , Ossos Pélvicos/lesões , Qualidade de Vida , Adulto , Fraturas Ósseas/epidemiologia , Fraturas Ósseas/terapia , Humanos , Estudos Retrospectivos
6.
Anaesthesist ; 67(7): 504-511, 2018 07.
Artigo em Alemão | MEDLINE | ID: mdl-29767825

RESUMO

BACKGROUND: Palliative sedation (PS) serves as a therapeutic option in cases of otherwise intractable suffering. As the use of sedative and hypnotic medication in many diverse situations is a core competency of anesthesiology, anesthesiologists are confronted with questions of sedative therapy at the end of life in institutions for specialized palliative care, in intensive care units and intermediate care wards. In recent years a number of guidelines have been published internationally but so far no official guidelines exist in Germany. The most recognized document is the European Association for Palliative Care (EAPC) framework on PS. This project aims to develop a German language template for the preparation, application, documentation and evaluation of PS according to the current frameworks, especially the EAPC framework on PS. METHODS: A first draft of the template was generated by the project team using the EAPC framework and individual templates of various institutions, which had been collected during a previous project. Professionals (n = 136) from inpatient and outpatient specialist palliative and hospice care were invited to assess all items of the draft regarding "relevance", "wording" and "feasibility" in an online Delphi survey (Unipark®, Questback, Cologne, Germany). After the second Delphi round an expert panel was asked to reflect the results and generate a final draft. Approval was granted if acceptance exceeded 75% of participants. RESULTS: The 3 rounds of the Delphi process were completed by 64, 46 and 41 participants, respectively. The Delphi process as well as the expert panel led to significant changes of the template. The indications for PS had to be clarified. The significance of documentation of vital parameters, such as oxygen saturation, blood pressure or respiratory rate during PS was intensively discussed. In many teams, predominantly hospice or outpatient palliative care teams, it seems to be difficult to measure these parameters or it is regarded as inappropriate in a palliative care setting. In contrast, the EAPC framework recommends monitoring of vital parameters in cases of intermittent or respite sedation. Finally, a solution was found to support documentation of additional data without the explicit mentioning of specific parameters. After the third Delphi round, all 16 items of the documentation template reached consensus with respect to relevance (82.9-100%), clarity of wording (80.5-100%), and feasibility in practice (78-100%). CONCLUSION: This article provides an empirically based, multiprofessional consented documentation template for PS. Core elements of the documentation of PS are the indications and the decision process towards PS. During the treatment, at least the level of sedation and the symptom burden have to be recorded. The documentation of vital signs during PS remains a highly disputed topic. The presented data suggest that especially in outpatient settings and in hospices measuring and documentation of vital parameters is uncommon and therefore is often regarded as not feasible. This template can help to support the medically and ethically sound use of PS and facilitate research. The template can be accessed at http://www.palliativmedizin.uk-erlangen.de/forschung/downloads/ .


Assuntos
Sedação Profunda/normas , Documentação/normas , Guias como Assunto , Cuidados Paliativos/normas , Anestesia , Consenso , Tomada de Decisões , Atenção à Saúde , Alemanha , Humanos , Idioma , Inquéritos e Questionários
7.
Clin Genet ; 89(1): 74-81, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25652421

RESUMO

Cornelia de Lange syndrome (CdLS) and KBG syndrome are two distinct developmental pathologies sharing common features such as intellectual disability, psychomotor delay, and some craniofacial and limb abnormalities. Mutations in one of the five genes NIPBL, SMC1A, SMC3, HDAC8 or RAD21, were identified in at least 70% of the patients with CdLS. Consequently, additional causative genes, either unknown or responsible of partially merging entities, possibly account for the remaining 30% of the patients. In contrast, KBG has only been associated with mutations in ANKRD11. By exome sequencing we could identify heterozygous loss-of-function mutations in ANKRD11 in two patients with the clinical diagnosis of CdLS. Both patients show features reminiscent of CdLS such as characteristic facies as well as a small head circumference which is not described for KBG syndrome. Patient A, who carries the mutation in a mosaic state, is a 4-year-old girl with features reminiscent of CdLS. Patient B, a 15-year-old boy, shows a complex phenotype which resembled CdLS during infancy, but has developed to a more KBG overlapping phenotype during childhood. These findings point out the importance of screening ANKRD11 in young CdLS patients who were found to be negative for mutations in the five known CdLS genes.


Assuntos
Síndrome de Cornélia de Lange/diagnóstico , Síndrome de Cornélia de Lange/genética , Exoma , Estudos de Associação Genética , Fenótipo , Proteínas Repressoras/genética , Adolescente , Pré-Escolar , Fácies , Feminino , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Masculino
8.
Clin Genet ; 89(5): 564-73, 2016 May.
Artigo em Inglês | MEDLINE | ID: mdl-26671848

RESUMO

Cornelia de Lange syndrome (CdLS) is a clinically heterogeneous disorder characterized by typical facial dysmorphism, cognitive impairment and multiple congenital anomalies. Approximately 75% of patients carry a variant in one of the five cohesin-related genes NIPBL, SMC1A, SMC3, RAD21 and HDAC8. Herein we report on the clinical and molecular characterization of 11 patients carrying 10 distinct variants in HDAC8. Given the high number of variants identified so far, we advise sequencing of HDAC8 as an indispensable part of the routine molecular diagnostic for patients with CdLS or CdLS-overlapping features. The phenotype of our patients is very broad, whereas males tend to be more severely affected than females, who instead often present with less canonical CdLS features. The extensive clinical variability observed in the heterozygous females might be at least partially associated with a completely skewed X-inactivation, observed in seven out of eight female patients. Our cohort also includes two affected siblings whose unaffected mother was found to be mosaic for the causative mutation inherited to both affected children. This further supports the urgent need for an integration of highly sensitive sequencing technology to allow an appropriate molecular diagnostic, genetic counseling and risk prediction.


Assuntos
Síndrome de Cornélia de Lange/genética , Face/anormalidades , Assimetria Facial/genética , Histona Desacetilases/genética , Mutação , Proteínas Repressoras/genética , Sequência de Aminoácidos , Sequência de Bases , Criança , Síndrome de Cornélia de Lange/patologia , Assimetria Facial/patologia , Fácies , Feminino , Aconselhamento Genético , Genótipo , Humanos , Masculino , Fenótipo , Fatores de Risco , Análise de Sequência de DNA/métodos , Homologia de Sequência de Aminoácidos , Índice de Gravidade de Doença , Inativação do Cromossomo X
9.
Eur J Vasc Endovasc Surg ; 51(2): 194-201, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26482508

RESUMO

OBJECTIVE/BACKGROUND: The objective was to examine trends in abdominal aortic and iliac aneurysm repairs in Norway from 2001 to 2013, and study regional variations and organizational developments in this type of vascular surgery. METHODS: This was a retrospective study on aortic and iliac aneurysm repairs using data from the Norwegian Patient Register. The vascular centers were categorized by yearly volume of repairs into small (<18), medium (18-49) and large (≥50). Incidence rates were assessed per 100,000 ≥ 60 years. The percentage of endovascular aneurysm repairs (EVAR) was calculated among the conducted repairs at the three categories of centers and the South-Eastern, Western, Central, and Northern Norway Regional Health Authority (NRHA). RESULTS: The national incidence rates of intact repairs per 100,000 ≥ 60 years increased from 57.4 to 65.7 (p < .01). Ruptured repairs decreased from 19.7 to 9.2 (p < .01). The rate of EVAR increased from 6.0 to 29.9 (p < .01) in intact and from 0.4 to 2.5 (p < .01) in ruptured repairs. The vascular centers were reduced from 25 to 16. The rate of EVAR was 27.1% (p < .01) higher at large centers and 7.9% (p < .03) higher at medium centers compared with small centers, and from 11.1% to 15.7% higher (p < .01) at the Central, Western, and Northern NRHA compared with the South-Eastern NRHA, which had the most centers (also in the large category). The national increase in intact EVAR from 10.6% to 43.3% was less compared with many other Western countries. CONCLUSION: During the study period the rates of intact repairs increased while the ruptured repairs decreased. EVAR was associated with centers performing high volumes of abdominal aortic and iliac aneurysm repairs and regional authorities organized with few centers.


Assuntos
Aneurisma da Aorta Abdominal/cirurgia , Ruptura Aórtica/cirurgia , Implante de Prótese Vascular/tendências , Procedimentos Endovasculares/tendências , Aneurisma Ilíaco/cirurgia , Padrões de Prática Médica/tendências , Aneurisma da Aorta Abdominal/diagnóstico , Aneurisma da Aorta Abdominal/mortalidade , Ruptura Aórtica/diagnóstico , Ruptura Aórtica/mortalidade , Implante de Prótese Vascular/efeitos adversos , Implante de Prótese Vascular/mortalidade , Serviços Centralizados no Hospital/tendências , Procedimentos Endovasculares/efeitos adversos , Procedimentos Endovasculares/mortalidade , Feminino , Hospitais com Alto Volume de Atendimentos/tendências , Hospitais com Baixo Volume de Atendimentos/tendências , Humanos , Aneurisma Ilíaco/diagnóstico , Aneurisma Ilíaco/mortalidade , Masculino , Pessoa de Meia-Idade , Noruega/epidemiologia , Sistema de Registros , Estudos Retrospectivos , Fatores de Tempo , Resultado do Tratamento
10.
Bioconjug Chem ; 26(3): 383-8, 2015 Mar 18.
Artigo em Inglês | MEDLINE | ID: mdl-25629889

RESUMO

Targeted drug-delivery methods are crucial for effective treatment of degenerative joint diseases such as osteoarthritis (OA). Toward this goal, we developed a small multivalent structure as a model drug for the attenuation of cartilage degradation. The DOTAM (1,4,7,10-tetraazacyclododecane-1,4,7,10-tetraacetic acid amide)-based model structure is equipped with the cathepsin D protease inhibitor pepstatin A, a fluorophore, and peptide moieties targeting collagen II. In vivo injection of these soluble probes into the knee joints of mice resulted in 7-day-long local retention, while the drug carrier equipped with a scrambled peptide sequence was washed away within 6-8 h. The model drug conjugate successfully reduced the cathepsin D protease activity as measured by release of GAG peptide. Therefore, these conjugates represent a promising first drug conjugate for the targeted treatment of degenerative joint diseases.


Assuntos
Acetamidas/administração & dosagem , Cartilagem/efeitos dos fármacos , Portadores de Fármacos/administração & dosagem , Sistemas de Liberação de Medicamentos/métodos , Compostos Heterocíclicos com 1 Anel/administração & dosagem , Osteoartrite/tratamento farmacológico , Acetamidas/metabolismo , Animais , Artrite Experimental/tratamento farmacológico , Artrite Experimental/metabolismo , Artrite Experimental/patologia , Cartilagem/metabolismo , Cartilagem/patologia , Portadores de Fármacos/metabolismo , Compostos Heterocíclicos com 1 Anel/metabolismo , Camundongos , Osteoartrite/metabolismo , Osteoartrite/patologia , Suínos
11.
Phys Rev Lett ; 115(13): 132501, 2015 Sep 25.
Artigo em Inglês | MEDLINE | ID: mdl-26451548

RESUMO

New technical developments have led to a 2 orders of magnitude improvement of the resolution of the collinear resonance ionization spectroscopy (CRIS) experiment at ISOLDE, CERN, without sacrificing the high efficiency of the CRIS technique. Experimental linewidths of 20(1) MHz were obtained on radioactive beams of francium, allowing us for the first time to determine the electric quadrupole moment of the short lived [t_{1/2}=22.0(5) ms] ^{219}Fr Q_{s}=-1.21(2) eb, which would not have been possible without the advantages offered by the new method. This method relies on a continuous-wave laser and an external Pockels cell to produce narrow-band light pulses, required to reach the high resolution in two-step resonance ionization. Exotic nuclei produced at rates of a few hundred ions/s can now be studied with high resolution, allowing detailed studies of the anchor points for nuclear theories.

12.
Qual Life Res ; 24(8): 2015-23, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-25676859

RESUMO

BACKGROUND: The Short Musculoskeletal Function Assessment (SMFA) is widely used in both research and clinical practice. Despite its frequent use, normative data of the SMFA have remained limited. Aim of this study was to gather normative data for the Dutch SMFA (SMFA-NL). METHODS: The SMFA-NL consists of two indices (function index and bother index) and four subscales (upper extremity dysfunction, lower extremity dysfunction, mental and emotional problems, and problems with daily activities). A total of 900 patients were invited to fill in the SMFA-NL. Six age groups (18-24, 25-34, 35-44, 45-54, 55-64, and 65-75 years) were constructed. Analysis of variance, t tests, and regression analyses were used to assess age and gender effects. RESULTS: The response rate was 97 %. There was a significant difference between men and women in scores on all indices and subscales (range p < 0.001 to p = 0.002), except for the upper extremity dysfunction subscale (p = 0.06). A significant interaction effect was found between gender and age for the upper extremity dysfunction subscale; a larger decrease in score with increasing age was observed for women, compared with men. Significant differences were found between age groups for the bother index (p < 0.001), lower extremity dysfunction subscale (p = 0.001), and the problems with daily activities subscale (p = 0.002). CONCLUSION: Significant differences in SMFA-NL scores were found between men and women and between different age groups. These SMFA-NL normative data provide an opportunity of benchmarking health status of participants with musculoskeletal disorders or injuries against their age- and gender-matched peers in the Dutch population.


Assuntos
Avaliação da Deficiência , Nível de Saúde , Doenças Musculoesqueléticas/fisiopatologia , Autorrelato , Inquéritos e Questionários , Adolescente , Adulto , Idoso , Feminino , Humanos , Extremidade Inferior/fisiologia , Masculino , Pessoa de Meia-Idade , Países Baixos , Qualidade de Vida , Adulto Jovem
14.
Angew Chem Int Ed Engl ; 54(22): 6511-5, 2015 May 26.
Artigo em Inglês | MEDLINE | ID: mdl-25877959

RESUMO

Structure-based drug design (SBDD) is a powerful and widely used approach to optimize affinity of drug candidates. With the recently introduced INPHARMA method, the binding mode of small molecules to their protein target can be characterized even if no spectroscopic information about the protein is known. Here, we show that the combination of the spin-diffusion-based NMR methods INPHARMA, trNOE, and STD results in an accurate scoring function for docking modes and therefore determination of protein-ligand complex structures. Applications are shown on the model system protein kinase A and the drug targets glycogen phosphorylase and soluble epoxide hydrolase (sEH). Multiplexing of several ligands improves the reliability of the scoring function further. The new score allows in the case of sEH detecting two binding modes of the ligand in its binding site, which was corroborated by X-ray analysis.


Assuntos
Desenho de Fármacos , Ligantes , Proteínas/química , Sítios de Ligação , Cristalografia por Raios X , Proteínas Quinases Dependentes de AMP Cíclico/antagonistas & inibidores , Proteínas Quinases Dependentes de AMP Cíclico/metabolismo , Difusão , Epóxido Hidrolases/antagonistas & inibidores , Epóxido Hidrolases/metabolismo , Glicogênio Fosforilase/antagonistas & inibidores , Glicogênio Fosforilase/metabolismo , Espectroscopia de Ressonância Magnética , Simulação de Acoplamento Molecular , Ligação Proteica , Proteínas/metabolismo
15.
Phys Rev Lett ; 113(26): 262504, 2014 Dec 31.
Artigo em Inglês | MEDLINE | ID: mdl-25615316

RESUMO

We optimize chiral interactions at next-to-next-to leading order to observables in two- and three-nucleon systems and compute Gamow-Teller transitions in 14C and (22,24)O using consistent two-body currents. We compute spectra of the daughter nuclei 14N and (22,24)F via an isospin-breaking coupled-cluster technique, with several predictions. The two-body currents reduce the Ikeda sum rule, corresponding to a quenching factor q2≈0.84-0.92 of the axial-vector coupling. The half-life of 14C depends on the energy of the first excited 1+ state, the three-nucleon force, and the two-body current.

16.
Angew Chem Int Ed Engl ; 53(29): 7669-73, 2014 Jul 14.
Artigo em Inglês | MEDLINE | ID: mdl-24888522

RESUMO

The synthesis and evaluation of two cathepsin S-specific probes is described. For long-term retention of the probe at the target site and a high signal-to-noise ratio, we introduced a lipidation approach via the simple attachment of palmitoic acid to the reporter. After cathepsin S-specific cleavage in cultured cells and in a grafted tumor mouse model, fluorescence increased owing to dequenching and we observed an intracellular accumulation of the fluorescence in the target tissue. The lipidated probe provided a prolonged and strongly fluorescent signal in tumors when compared to the very similar non-lipidated probe, demonstrating that non-invasive tumor identification is feasable. The homing principle by probe lipidation might also work for selective administration of cytotoxic compounds to specifically reduce tumor mass.


Assuntos
Catepsinas/metabolismo , Metabolismo dos Lipídeos , Neoplasias Experimentais/patologia , Animais , Camundongos , Neoplasias Experimentais/enzimologia , Especificidade por Substrato
17.
Biol Chem ; 394(2): 307-16, 2013 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-23152404

RESUMO

Osteoarthritis and rheumatoid arthritis are destructive joint diseases that involve the loss of articular cartilage. Degradation of cartilage extracellular matrix is believed to occur due to imbalance between the catabolic and anabolic processes of resident chondrocytes. Previous work has suggested that various lysosomal cysteine cathepsins participate in cartilage degeneration; however, their exact roles in disease development and progression have not been elucidated. In order to study degradation processes under conditions resembling the in vivo milieu of the cartilage, we cultivated chondrocytes on a type II collagen-containing matrix. Stimulation of the cultivated chondrocytes with interleukin-1α and/or tumor necrosis factor α resulted in a time-dependent increase in cathepsin S expression and induced its secretion into the conditioned media. Using a novel bioluminescent activity-based probe, we were able to demonstrate a significant increase in proteolytic activity of cathepsin S in the conditioned media of proinflammatory cytokine-stimulated chondrocytes. For the first time, cathepsin S was demonstrated to be secreted from chondrocytes upon stimulation with the proinflammatory cytokines, and displayed proteolytic activity in culture supernatants. Its stability at neutral pH and potent proteolytic activity on extracellular matrix components mean that cathepsin S may contribute significantly to cartilage degradation and may thus be considered a potential drug target in joint diseases.


Assuntos
Catepsinas/biossíntese , Catepsinas/metabolismo , Condrócitos/metabolismo , Inflamação/metabolismo , Interleucina-1alfa/metabolismo , Fator de Necrose Tumoral alfa/metabolismo , Células Cultivadas , Humanos , Proteólise
18.
Phys Rev Lett ; 111(21): 212501, 2013 Nov 22.
Artigo em Inglês | MEDLINE | ID: mdl-24313482

RESUMO

The magnetic moments and isotope shifts of the neutron-deficient francium isotopes (202-205)Fr were measured at ISOLDE-CERN with use of collinear resonance ionization spectroscopy. A production-to-detection efficiency of 1% was measured for (202)Fr. The background from nonresonant and collisional ionization was maintained below one ion in 10(5) beam particles. Through a comparison of the measured charge radii with predictions from the spherical droplet model, it is concluded that the ground-state wave function remains spherical down to (205)Fr, with a departure observed in (203)Fr (N=116).

19.
Anal Bioanal Chem ; 404(8): 2163-72, 2012 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-22865006

RESUMO

The in-source resonance ionization mass spectrometry technique was applied for quantification of ultratrace amounts of plutonium isotopes as a proof of principle study. In addition to an overall detection limit of 10(4) to 10(5) atoms, this method enables the unambiguous identification and individual quantification of the plutonium isotopes (238)Pu and (241)Pu which are of relevance for dating of radiogenic samples. Due to the element-selective ionization process, these isotopes can be measured even under a high surplus of isobaric contaminations from (238)U or (241)Am, which considerably simplifies chemical preparation. The technique was developed, tested, and characterized on a variety of synthetic and calibration samples and is presently applied to analyze environmental samples.


Assuntos
Espectrometria de Massas , Plutônio/análise , Isótopos/análise , Limite de Detecção
20.
Anal Bioanal Chem ; 404(8): 2173-6, 2012 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-22890539

RESUMO

Laser resonance ionization mass spectrometry (RIMS) represents one of the most sensitive and selective techniques for ultra trace determination of long-lived radioisotopes. The isotope (99g)Tc constitutes a specific candidate of high relevance concerning its environmental behavior as well as fundamental research applications. Based on the recent precision determination of the ionization potential of technetium by laser resonance ionization, refined resonant optical excitation pathways have been derived for analytical determination of ultra trace amounts of (99g)Tc by laser mass spectrometric approaches. The state of the art and the specifications of RIMS-based ultra trace determination for (99g)Tc, leading to a level of detection of ε ≈ 3 × 10(-4) atoms (3 µBq), are reported.

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