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1.
BMC Psychiatry ; 21(1): 496, 2021 10 11.
Artigo em Inglês | MEDLINE | ID: mdl-34635063

RESUMO

BACKGROUND: Seventy per cent of patients with psychotic disorders has paranoid delusions. Paranoid delusions are associated with significant distress, hospital admission and social isolation. Cognitive-behavioural therapy for psychosis (CBTp) is the primary psychological treatment, but the median effect size is only small to medium. Virtual reality (VR) has a great potential to improve the effectiveness of CBTp. In a previous study, we found that VR based CBT (VRcbt) for paranoid delusions is superior to waiting list. As a next step, a direct comparison with CBTp is needed. The present study aims to investigate whether VRcbt is more effective and cost-effective than regular CBTp in treating paranoid delusions and improving daily life social functioning of patients with psychotic disorders. METHODS: A total of 106 patients with DSM-5 diagnosis of psychotic disorder and at least moderate level of paranoid ideations will be recruited for this multicentre randomized controlled trial (RCT). Patients will be randomized to either VRcbt or standard CBTp for paranoid delusions. VRcbt consists of maximum 16 sessions in virtual social situations that trigger paranoid ideations and distress, delivered in an 8-12 week time frame. Standard CBTp also consists of maximum 16 sessions including exposure and behavioural experiments, delivered in an 8-12 week time frame. The two groups will be compared at baseline, post-treatment and six months follow-up. Primary outcome is the level of paranoid ideations in daily life social situations, measured with ecological momentary assessments (EMA) at semi-random moments ten times a day during seven days, before and after treatment. Every session, participants and therapists will rate the level of paranoid ideation and global clinical impression. DISCUSSION: Comparison of VRcbt and CBTp will provide information about the relative (cost-) effectiveness of VRcbt for this population. VRcbt may become a preferred psychological treatment for paranoid delusions and social anxiety in patients with psychotic disorder. TRIAL REGISTRATION: Netherlands Trial Register, NL7758. Registered on 23 May 2019.


Assuntos
Terapia Cognitivo-Comportamental , Transtornos Psicóticos , Terapia de Exposição à Realidade Virtual , Realidade Virtual , Delusões/terapia , Humanos , Estudos Multicêntricos como Assunto , Transtornos Psicóticos/terapia , Ensaios Clínicos Controlados Aleatórios como Assunto , Resultado do Tratamento
2.
Clin Oral Investig ; 25(10): 5795-5805, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-33821321

RESUMO

OBJECTIVES: Topical drug administration is commonly applied to control oral inflammation. However, it requires sufficient drug adherence and a high degree of bioavailability. Here, we tested the hypothesis whether an ester-based core-multishell (CMS) nanocarrier is a suitable nontoxic drug-delivery system that penetrates efficiently to oral mucosal tissues, and thereby, increase the bioavailability of topically applied drugs. MATERIAL AND METHODS: To evaluate adhesion and penetration, the fluorescence-labeled CMS 10-E-15-350 nanocarrier was applied to ex vivo porcine masticatory and lining mucosa in a Franz cell diffusion assay and to an in vitro 3D model. In gingival epithelial cells, potential cytotoxicity and proliferative effects of the nanocarrier were determined by MTT and sulphorhodamine B assays, respectively. Transepithelial electrical resistance (TEER) was measured in presence and absence of CMS 10-E-15-350 using an Endohm-12 chamber and a volt-ohm-meter. Cellular nanocarrier uptake was analyzed by laser scanning microscopy. Inflammatory responses were determined by monitoring pro-inflammatory cytokines using real-time PCR and ELISA. RESULTS: CMS nanocarrier adhered to mucosal tissues within 5 min in an in vitro model and in ex vivo porcine tissues. The CMS nanocarrier exhibited no cytotoxic effects and induced no inflammatory responses. Furthermore, the physical barrier expressed by the TEER remained unaffected by the nanocarrier. CONCLUSIONS: CMS 10-E-15-350 adhered to the oral mucosa and adhesion increased over time which is a prerequisite for an efficient drug release. Since TEER is unaffected, CMS nanocarrier may enter the oral mucosa transcellularly. CLINICAL RELEVANCE: Nanocarrier technology is a novel and innovative approach for efficient topical drug delivery at the oral mucosa.


Assuntos
Nanopartículas , Absorção Cutânea , Administração Cutânea , Animais , Portadores de Fármacos/metabolismo , Ésteres/metabolismo , Mucosa Bucal , Pele , Suínos
3.
Epidemiol Mikrobiol Imunol ; 68(2): 104-108, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31398984

RESUMO

The Bartonella genus comprises more than 20 species of Gram-negative rods which are difficult to culture. These are facultative intracellular bacteria. Humans are reservoir hosts for B. quintana and B. bacilliformis or accidental hosts for other species. Bartonella is a cause of zoonosis. Bartonella infection can be completely asymptomatic or can be linked to various conditions. Our experience with Bartonella endocarditis from 2012-2017 is presented. The most effective diagnostic method for Bartonella endocarditis is PCR detection of DNA of the pathogen from excised valve tissue. The European Society of Cardiology (ESC) in the guidelines from 2015 recommends the combination doxycycline gentamycin for the treatment of Bartonella endocarditis.


Assuntos
Infecções por Bartonella , Endocardite , Animais , Bartonella , Infecções por Bartonella/diagnóstico , Infecções por Bartonella/tratamento farmacológico , Endocardite/diagnóstico , Endocardite/tratamento farmacológico , Gentamicinas/uso terapêutico , Humanos , Zoonoses/diagnóstico , Zoonoses/tratamento farmacológico
4.
Diabet Med ; 2018 Apr 23.
Artigo em Inglês | MEDLINE | ID: mdl-29687658

RESUMO

AIM: The United Kingdom Prospective Diabetes Study (UKPDS) study showed that glycaemic control (HbA1c ) can predict vascular complications in Type 2 diabetes mellitus. The Diabetes Control and Complications Trial (DCCT) study showed that accumulation of advanced glycation end products (AGEs) from skin biopsies predicts vascular complications in Type 1 diabetes. Previously, we showed that tissue AGEs can be measured non-invasively using skin autofluorescence (SAF). The aim of this study was to compare the predictive value of HbA1c and SAF for new macrovascular events and microvascular complications in people with Type 2 diabetes. METHODS: A prospective cohort study of 563 participants, median age 64 years [interquartile range (IQR) 57-72], diabetes duration of 13 years, from five Dutch hospitals was performed. RESULTS: After a median follow-up of 5.1 (IQR 4.3-5.9) years, 79 (15%) participants had died and 49 (9%) were lost to follow-up. Some 133 (26%) developed a microvascular complication and 189 (37%) a macrovascular event. Tertiles of HbA1c were significantly associated with development of microvascular complications (log rank P = 0.022), but not with macrovascular events. Tertiles of SAF were significantly associated with macrovascular events (log rank P = 0.003). Cox regression analysis showed SAF was associated with macrovascular events: crude hazard ratio (HR) 1.53 (P < 0.001) per unit increase, HR 1.28 (P = 0.03) after correction for UKPDS score. HbA1c was predictive for microvascular complications: crude HR 1.20 (P = 0.004), HR 1.20 (P = 0.004) after correction for UKPDS score. CONCLUSION: This study shows that tissue accumulation of AGEs, assessed by SAF, is associated with development of macrovascular events in people with Type 2 diabetes, whereas HbA1c is associated with the development of microvascular complications.

5.
J Periodontal Res ; 53(1): 57-65, 2018 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-28898420

RESUMO

BACKGROUND AND OBJECTIVES: In the oral cavity, the mucosal tissues may develop a number of different pathological conditions, such as inflammatory diseases (gingivitis, periodontitis) and autoimmune disorders (eg, oral lichen planus) that require therapy. The application of topical drugs is one common therapeutic approach. However, their efficacy is limited. Dilution effects due to saliva hinder the adherence and the penetration of drug formulations. Therefore, the bioavailability of oral topical drugs is insufficient, and patients may suffer from disease over years, if not life-long. MATERIAL AND METHODS: In the present study, we characterized core-multishell (CMS) nanocarriers for their potential use as drug delivery systems at oral mucosal tissues. For this purpose, we prepared porcine masticatory as well as buccal mucosa and performed Franz cell diffusion experiments. Penetration of fluorescently labeled CMS nanocarriers into the mucosal tissue was analyzed using confocal laser scanning microscopy. Upon exposure to CMS nanocarriers, the metabolic and proliferative activity of gingival epithelial cells was determined by MTT and sulforhodamine B assays, respectively. RESULTS: Here, we could show that the carriers penetrate into both mucosal tissues, while particles penetrate deeper into the masticatory mucosa. Electron paramagnetic resonance spectroscopy revealed that the 3-carboxy-2,2,5,5-tetramethyl-1-pyrrolidinyloxy-labeled glucocorticoid dexamethasone loaded on to the CMS nanocarriers was released from the carriers in both mucosal tissues but with a higher efficiency in the buccal mucosa. The release from the nanocarriers is in both cases superior compared to the release from a conventional cream, which is normally used for the treatment of inflammatory conditions in the oral cavity. The CMS nanocarriers exhibited neither cytotoxic nor proliferative effects in vitro. CONCLUSION: These findings suggested that CMS nanocarriers might be an innovative approach for topical drug delivery in the treatment of oral inflammatory diseases.


Assuntos
Dexametasona/administração & dosagem , Portadores de Fármacos , Sistemas de Liberação de Medicamentos , Glucocorticoides/administração & dosagem , Mucosa Bucal/efeitos dos fármacos , Nanopartículas , Animais , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Dexametasona/farmacocinética , Células Epiteliais/efeitos dos fármacos , Gengiva/citologia , Glucocorticoides/farmacocinética , Espectroscopia de Ressonância Magnética , Microscopia Confocal
6.
J Periodontal Res ; 52(4): 745-754, 2017 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-28321852

RESUMO

BACKGROUND AND OBJECTIVES: The aim of this clinical cross-sectional study was to determine the level of active matrix metalloproteinase-8 (aMMP-8) and periodontal pathogenic bacteria in gingival crevicular fluid in patients with rheumatoid arthritis (RA) with varying periodontal conditions. MATERIAL AND METHODS: In total, 103 patients with RA and 104 healthy controls (HC) were included. The assessment of periodontal status included periodontal probing depth, bleeding on probing and clinical attachment loss. Periodontal disease was classified as healthy/mild, moderate or severe. For the determination of aMMP-8 levels using enzyme-linked immunosorbent assay and periodontal pathogenic bacteria using polymerase chain reaction, samples of gingival crevicular fluid were taken from the deepest gingival pockets. The statistical analyses used included a Mann-Whitney U-test, a chi-squared test or a Fisher's exact test, and the significance level was set at α = 5%. RESULTS: We found that 65% of patients with RA and 79% of HC had moderate to severe periodontal disease (p = 0.02). The prevalence of periodontal pathogens was almost equal (p > 0.05). Furthermore, depending on periodontal disease severity only minor differences in bacterial prevalence were detected. With increasing severity of periodontal disease, higher aMMP-8 levels were observed. Accordingly, a significant difference in patients with moderate periodontal disease (RA: 15.3 ± 13.8; HC: 9.1 ± 9.1; p ≤ 0.01) and severe periodontal disease (RA: 21.7 ± 13.3; HC: 13.1 ± 8.6; p = 0.07) was detected, with a greater tendency in the latter group. CONCLUSION: The increased aMMP-8 levels in the RA group indicate that the presence of RA appears to have an influence on the host response at a comparable level of bacterial load and periodontal disease severity.


Assuntos
Artrite Reumatoide/complicações , Líquido do Sulco Gengival/enzimologia , Líquido do Sulco Gengival/microbiologia , Metaloproteinase 8 da Matriz/metabolismo , Periodontite/enzimologia , Periodontite/microbiologia , Adolescente , Adulto , Idoso , Estudos Transversais , Ensaio de Imunoadsorção Enzimática , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Perda da Inserção Periodontal/microbiologia , Índice Periodontal , Bolsa Periodontal/microbiologia , Reação em Cadeia da Polimerase
7.
J Intern Med ; 280(2): 209-20, 2016 08.
Artigo em Inglês | MEDLINE | ID: mdl-26864622

RESUMO

Obesity, which affects 600 million adults worldwide, is a major risk factor for type 2 diabetes (T2D) and insulin resistance. Current therapies for these metabolic disorders include weight management by lifestyle intervention or bariatric surgery and pharmacological treatment with the aim of regulating blood glucose. Probably because of their short-term effectiveness, these therapies have not been able to stop the rapidly rising prevalence of T2D over the past decades, highlighting an urgent need to develop new therapeutic strategies. The role of immune cells, such as macrophages, in insulin resistance has been extensively studied. Major advances have been made to elucidate the role of adipose tissue macrophages in these pathogeneses. Recently, anti-inflammatory drugs have been suggested as an alternative treatment for T2D, and clinical trials of these agents are currently ongoing. In addition, results of previous clinical trials using antibodies against inflammatory cytokines, which showed modest effects, are now being rigorously re-evaluated. However, it is still unclear how liver macrophages [termed Kupffer cells (KCs)], which constitute the major source of macrophages in the body, contribute to the development of insulin resistance. In this review, we will discuss the present understanding of the role of liver immune cells in the development of insulin resistance. We will particularly focus on KCs, which could represent an attractive target for the treatment of metabolic diseases.


Assuntos
Resistência à Insulina/imunologia , Células de Kupffer/imunologia , Fígado/imunologia , Animais , Diabetes Mellitus Tipo 2/imunologia , Hepatite/imunologia , Hepatócitos/imunologia , Humanos , Obesidade/imunologia
8.
Tijdschr Psychiatr ; 58(3): 223-7, 2016.
Artigo em Holandês | MEDLINE | ID: mdl-26979854

RESUMO

BACKGROUND: Research has shown that young adults with psychotic disorders frequently have problems relating to sexuality, intimacy and relationships. Such problems are often neglected in clinical practice. AIM: To perform a study that explores, on the basis of focus groups, how issues such as sexuality, intimacy and relationships can be addressed as part of the treatment of adolescents suffering from a psychotic disorder. METHOD: We created eight focus groups consisting of clients attending the department of psychotic disorders and caregivers who worked there. The meetings of each focus group were fully transcribed and analysed by means of Nvivo. RESULTS: Clients indicated they wanted to address the topics of sexuality, intimacy and relationships in a group setting. They expressed the wish to have mixed gender groups and decided that in the group discussions the main focus should be on the exchange of personal experiences. CONCLUSION: In our view, it is desirable that psychiatry should pay more attention to the subject of sexuality. By giving adolescents suffering from psychotic disorders the opportunity to discuss their experiences, problems and feelings of insecurity in a group setting and in a low-threshold environment, psychiatrists can greatly improve the quality of care that they provide for their patients.


Assuntos
Relações Interpessoais , Transtornos Psicóticos/psicologia , Parceiros Sexuais/psicologia , Sexualidade/psicologia , Adolescente , Feminino , Grupos Focais , Humanos , Masculino , Transtornos Psicóticos/fisiopatologia , Sexualidade/fisiologia
9.
J Intern Med ; 275(1): 59-70, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-23981104

RESUMO

OBJECTIVES: We investigated whether metformin can improve endothelial function and decrease inflammatory activity, and thereby decrease the risk of atherothrombotic disease. SUBJECTS AND DESIGN: A randomized, placebo-controlled trial with a follow-up period of 4.3 years set in the outpatient clinics of three nonacademic hospitals (Hoogeveen, Meppel and Coevorden Hospitals, the Netherlands). A total of 390 patients with type 2 diabetes treated with insulin were included. Either metformin 850 mg or placebo (one to three times daily) was added to insulin therapy. Urinary albumin excretion and plasma levels of von Willebrand factor (vWf), soluble vascular adhesion molecule-1 (sVCAM-1), soluble E-selectin (sE-selectin), tissue-type plasminogen activator (t-PA), plasminogen activator inhibitor-1 (PAI-1), C-reactive protein (CRP) and soluble intercellular adhesion molecule-1 (sICAM-1) were measured at baseline and after 4, 17, 30, 43 and 52 months. RESULTS: Metformin significantly reduced levels of vWF, sVCAM-1, t-PA, PAI-1, CRP and sICAM-1, which, except for CRP, remained significant after adjustment for baseline differences in age, sex, smoking and severity of previous cardiovascular (CV) disease. No effects on urinary albumin excretion or sE-selectin were observed. The improvements in vWf and sVCAM-1 statistically explained about 34% of the reduction in the risk of CV morbidity and mortality associated with metformin treatment in this study. CONCLUSIONS: Metformin is associated with improvement in some (vWF and sVCAM-1) but not all markers of endothelial function, which may explain why it is associated with a decreased risk of CV disease in type 2 diabetes.


Assuntos
Diabetes Mellitus Tipo 2 , Endotélio Vascular , Molécula 1 de Adesão Intercelular/sangue , Metformina , Fator de von Willebrand/análise , Idoso , Biomarcadores/análise , Biomarcadores/sangue , Diabetes Mellitus Tipo 2/tratamento farmacológico , Diabetes Mellitus Tipo 2/metabolismo , Diabetes Mellitus Tipo 2/fisiopatologia , Monitoramento de Medicamentos , Quimioterapia Combinada , Endotélio Vascular/metabolismo , Endotélio Vascular/fisiopatologia , Feminino , Humanos , Hipoglicemiantes/administração & dosagem , Hipoglicemiantes/efeitos adversos , Insulina/administração & dosagem , Masculino , Metformina/administração & dosagem , Metformina/efeitos adversos , Pessoa de Meia-Idade , Tempo , Resultado do Tratamento
10.
Genes Immun ; 14(7): 453-61, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-23985573

RESUMO

Interleukin-7 receptor alpha (IL7RA) is among the top listed candidate genes influencing the risk to develop multiple sclerosis (MS), an inflammatory demyelinating disease of the central nervous system. Soluble IL-7RA (sIL-7RA) protein and mRNA levels vary among the four common IL7RA haplotypes. Here we show and confirm that protective haplotype carriers have three times lower sIL-7RA serum levels than the other three haplotypes. High sIL-7RA concentrations significantly decrease IL-7-mediated STAT5 phosphorylation in CD4(+) T cells. Transcriptome analysis of unstimulated and stimulated CD4(+) T cells of MS patients carrying the different IL7RA haplotypes revealed complex and overlapping patterns in genes participating in cytokine signaling networks, apoptosis, cell cycle progression and cell differentiation. Our findings indicate that genetic variants of IL7RA result in haplotype-associated differential responsiveness to immunological stimuli that influence MS susceptibility not exclusively by varying levels of sIL-7RA.


Assuntos
Redes Reguladoras de Genes , Haplótipos , Subunidade alfa de Receptor de Interleucina-7/genética , Esclerose Múltipla/genética , Transcrição Gênica , Adulto , Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD4-Positivos/metabolismo , Feminino , Humanos , Subunidade alfa de Receptor de Interleucina-7/metabolismo , Células Matadoras Naturais/imunologia , Células Matadoras Naturais/metabolismo , Masculino , Pessoa de Meia-Idade , Esclerose Múltipla/imunologia , Fosforilação , Polimorfismo de Nucleotídeo Único , Fator de Transcrição STAT5/metabolismo
11.
Opt Express ; 21(14): 16473-85, 2013 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-23938498

RESUMO

By means of a metal opto-acoustic transducer we generate quasi-longitudinal and quasi-transverse picosecond strain pulses in a (311)-GaAs substrate and monitor their propagation by picosecond acoustic interferometry. By probing at the sample side opposite to the transducer the signals related to the compressive and shear strain pulses can be separated in time. In addition to conventional monitoring of the reflected probe light intensity we monitor also the polarization rotation of the optical probe beam. This polarimetric technique results in improved sensitivity of detection and provides comprehensive information about the elasto-optical anisotropy. The experimental observations are in a good agreement with a theoretical analysis.


Assuntos
Arsenicais/química , Gálio/química , Interferometria/instrumentação , Técnicas Fotoacústicas/instrumentação , Refratometria/instrumentação , Transdutores , Desenho de Equipamento , Análise de Falha de Equipamento
12.
Artigo em Inglês | MEDLINE | ID: mdl-37288385

RESUMO

Abstract: The BASE collaboration at the antiproton decelerator/ELENA facility of CERN compares the fundamental properties of protons and antiprotons with ultra-high precision. Using advanced Penning trap systems, we have measured the proton and antiproton magnetic moments with fractional uncertainties of 300 parts in a trillion (p.p.t.) and 1.5 parts in a billion (p.p.b.), respectively. The combined measurements improve the resolution of the previous best test in that sector by more than a factor of 3000. Very recently, we have compared the antiproton/proton charge-to-mass ratios with a fractional precision of 16 p.p.t., which improved the previous best measurement by a factor of 4.3. These results allowed us also to perform a differential matter/antimatter clock comparison test to limits better than 3%. Our measurements enable us to set limits on 22 coefficients of CPT- and Lorentz-violating standard model extensions (SME) and to search for potentially asymmetric interactions between antimatter and dark matter. In this article, we review some of the recent achievements and outline recent progress towards a planned improved measurement of the antiproton magnetic moment with an at least tenfold improved fractional accuracy.

13.
Rev Sci Instrum ; 94(11)2023 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-37972020

RESUMO

Currently, the world's only source of low-energy antiprotons is the AD/ELENA facility located at CERN. To date, all precision measurements on single antiprotons have been conducted at this facility and provide stringent tests of fundamental interactions and their symmetries. However, magnetic field fluctuations from the facility operation limit the precision of upcoming measurements. To overcome this limitation, we have designed the transportable antiproton trap system BASE-STEP to relocate antiprotons to laboratories with a calm magnetic environment. We anticipate that the transportable antiproton trap will facilitate enhanced tests of charge, parity, and time-reversal invariance with antiprotons and provide new experimental possibilities of using transported antiprotons and other accelerator-produced exotic ions. We present here the technical design of the transportable trap system. This includes the transportable superconducting magnet, the cryogenic inlay consisting of the trap stack and detection systems, and the differential pumping section to suppress the residual gas flow into the cryogenic trap chamber.

14.
Rev Sci Instrum ; 94(10)2023 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-37874231

RESUMO

We present the design and characterization of a cryogenic window based on an ultra-thin aluminized biaxially oriented polyethylene terephthalate foil at T < 10 K, which can withstand a pressure difference larger than 1 bar at a leak rate <1×10-9 mbar l/s. Its thickness of ∼1.7 µm makes it transparent to various types of particles over a broad energy range. To optimize the transfer of 100 keV antiprotons through the window, we tested the degrading properties of different aluminum coated polymer foils of thicknesses between 900 and 2160 nm, concluding that 1760 nm foil decelerates antiprotons to an average energy of 5 keV. We have also explicitly studied the permeation as a function of coating thickness and temperature and have performed extensive thermal and mechanical endurance and stress tests. Our final design integrated into the experiment has an effective open surface consisting of seven holes with a diameter of 1 mm and will transmit up to 2.5% of the injected 100 keV antiproton beam delivered by the Antiproton Decelerator and Extra Low ENergy Antiproton ring facility of CERN.

15.
Rev Sci Instrum ; 94(12)2023 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-38109470

RESUMO

We present a fluorescence-detection system for laser-cooled 9Be+ ions based on silicon photomultipliers (SiPMs) operated at 4 K and integrated into our cryogenic 1.9 T multi-Penning-trap system. Our approach enables fluorescence detection in a hermetically sealed cryogenic Penning-trap chamber with limited optical access, where state-of-the-art detection using a telescope and photomultipliers at room temperature would be extremely difficult. We characterize the properties of the SiPM in a cryocooler at 4 K, where we measure a dark count rate below 1 s-1 and a detection efficiency of 2.5(3)%. We further discuss the design of our cryogenic fluorescence-detection trap and analyze the performance of our detection system by fluorescence spectroscopy of 9Be+ ion clouds during several runs of our sympathetic laser-cooling experiment.

16.
Strahlenther Onkol ; 188(1): 84-90, 2012 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-22194025

RESUMO

PURPOSE: The goal was to provide a quantitative evaluation of the accuracy of three different fixation systems for stereotactic radiotherapy and to evaluate patients' acceptance for all fixations. METHODS: A total of 16 consecutive patients with brain tumours undergoing fractionated stereotactic radiotherapy (SCRT) were enrolled after informed consent (Clinical trials.gov: NCT00181350). Fixation systems evaluated were the BrainLAB® mask, with and without custom made bite-block (fixations S and A) and a homemade neck support with bite-block (fixation B) based on the BrainLAB® frame. The sequence of measurements was evaluated in a randomized manner with a cross-over design and patients' acceptance by a questionnaire. RESULTS: The mean three-dimensional (3D) displacement and standard deviations were 1.16 ± 0.68 mm for fixation S, 1.92 ± 1.28 and 1.70 ± 0.83 mm for fixations A and B, respectively. There was a significant improvement of the overall alignment (3D vector) when using the standard fixation instead of fixation A or B in the craniocaudal direction (p = 0.037). Rotational deviations were significantly less for the standard fixation S in relation to fixations A (p = 0.005) and B (p = 0.03). EPI imaging with off-line correction further improved reproducibility. Five out of 8 patients preferred the neck support with the bite-block. CONCLUSION: The mask fixation system in conjunction with a bite-block is the most accurate fixation for SCRT reducing craniocaudal and rotational movements. Patients favoured the more comfortable but less accurate neck support. To optimize the accuracy of SCRT, additional regular portal imaging is warranted.


Assuntos
Adenoma/cirurgia , Neoplasias Encefálicas/cirurgia , Processamento de Imagem Assistida por Computador/instrumentação , Imageamento Tridimensional/instrumentação , Aceitação pelo Paciente de Cuidados de Saúde , Posicionamento do Paciente/instrumentação , Radiocirurgia/instrumentação , Planejamento da Radioterapia Assistida por Computador/instrumentação , Tomografia Computadorizada por Raios X/instrumentação , Artefatos , Astrocitoma/cirurgia , Humanos , Neoplasias Meníngeas/cirurgia , Meningioma/cirurgia , Países Baixos , Neuroma Acústico/cirurgia , Neoplasias Hipofisárias/cirurgia , Estudos Prospectivos , Inquéritos e Questionários
17.
Diabet Med ; 29(12): 1556-61, 2012 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-22937960

RESUMO

AIMS: Skin autofluorescence is a non-invasive marker of advanced glycation end product accumulation. In a previous study, skin autofluorescence correlated with and predicted micro- and macrovascular complications in Type 2 diabetes in a primary care setting. The present cross-sectional study aims to confirm the association between skin autofluorescence and diabetic complications in patients with Type 2 diabetes in a multi-centre secondary care setting. METHODS: We analysed 563 subjects with Type 2 diabetes mellitus from five Dutch hospitals. RESULTS: Median age was 64 years, median duration of diabetes 13 years and median HbA(1c) 58 mmol/mol (7.5%). Sixty-one per cent of patients had microvascular complications (38% nephropathy, 36% retinopathy, 35% neuropathy) and 42% had macrovascular complications. Median UK Prospective Diabetes Study 10-year risk for coronary events was 19%. Median skin autofluorescence was elevated compared with age-matched healthy control subjects: 2.77 (interquartile range 2.39-3.28) vs. 2.46 (2.08-2.84) arbitrary units. Skin autofluorescence was particularly increased in patients with complications: no complications, median 2.56 (2.26-2.90); microvascular complications, 2.79 (2.38-3.29); macrovascular complications, 2.85 (2.41-3.41); both micro- and macrovascular complications, 2.96 (2.56-3.60) arbitrary units, P < 0.001. Logistic regression analysis showed that age, duration of diabetes, renal function, gender, atrial fibrillation and skin autofluorescence were independently associated with macrovascular complications. Multiple regression analysis identified age, smoking, renal function, macrovascular complications and the number of microvascular complications as the determinants of skin autofluorescence. CONCLUSIONS: This study confirms that skin autofluorescence is increased in patients with Type 2 diabetes in a secondary care setting. Skin autofluorescence was associated with macrovascular complications in patients with diabetes and this association was independent of classical risk factors.


Assuntos
Doenças Cardiovasculares/metabolismo , Diabetes Mellitus Tipo 2/metabolismo , Angiopatias Diabéticas/metabolismo , Fluorescência , Produtos Finais de Glicação Avançada/metabolismo , Pele/química , Idoso , Biomarcadores/química , Pressão Sanguínea , Índice de Massa Corporal , Doenças Cardiovasculares/epidemiologia , Doenças Cardiovasculares/prevenção & controle , Estudos Transversais , Diabetes Mellitus Tipo 2/epidemiologia , Angiopatias Diabéticas/epidemiologia , Angiopatias Diabéticas/prevenção & controle , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Países Baixos/epidemiologia , Reprodutibilidade dos Testes , Fatores de Risco , Pele/irrigação sanguínea
18.
Rev Sci Instrum ; 93(9): 093303, 2022 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-36182508

RESUMO

We describe a newly developed polytetrafluoroethylene/copper capacitor driven by a cryogenic piezoelectric slip-stick stage and demonstrate with the chosen layout cryogenic capacitance tuning of ≈60 pF at ≈10 pF background capacitance. Connected to a highly sensitive superconducting toroidal LC circuit, we demonstrate tuning of the resonant frequency between 345 and 685 kHz, at quality factors Q > 100 000. Connected to a cryogenic ultra low noise amplifier, a frequency tuning range between 520 and 710 kHz is reached, while quality factors Q > 86 000 are achieved. This new device can be used as a versatile image current detector in high-precision Penning-trap experiments or as an LC-circuit-based haloscope detector to search for the conversion of axion-like dark matter to radio-frequency photons. This new development increases the sensitive detection bandwidth of our axion haloscope by a factor of ≈1000.

19.
Diabetologia ; 54(1): 180-9, 2011 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-20953578

RESUMO

AIMS/HYPOTHESIS: Extracellular signal-regulated kinase (ERK) activity is increased in adipose tissue in obesity and type 2 diabetes mellitus and strong evidences suggests that it is implicated in the downregulation of insulin signalling and action in the insulin-resistant state. To determine the role of ERK1 in obesity-associated insulin resistance in vivo, we inactivated Erk1 (also known as Mapk3) in obese leptin-deficient mice (ob/ob). METHODS: Mice of genotype ob/ob-Erk1⁻(/)⁻ were obtained by crossing Erk1⁻(/)⁻ mice with ob/ob mice. Glucose tolerance and insulin sensitivity were studied in 12-week-old mice. Tissue-specific insulin sensitivity, insulin signalling, liver steatosis and adipose tissue inflammation were determined. RESULTS: While ob/ob-Erk1⁻(/)⁻ and ob/ob mice exhibited comparable body weight and adiposity, ob/ob-Erk1⁻(/)⁻ mice did not develop hyperglycaemia and their glucose tolerance was improved. Hyperinsulinaemic-euglycaemic clamp studies demonstrated an increase in whole-body insulin sensitivity in the ob/ob-Erk1⁻(/)⁻ mice associated with an increase in both insulin-stimulated glucose disposal in skeletal muscles and adipose tissue insulin sensitivity. This occurred in parallel with improved insulin signalling in both tissues. The ob/ob-Erk1⁻(/)⁻ mice were also partially protected against hepatic steatosis with a strong reduction in acetyl-CoA carboxylase level. These metabolic improvements were associated with reduced expression of mRNA encoding inflammatory cytokine and T lymphocyte markers in the adipose tissue. CONCLUSIONS/INTERPRETATION: Our results demonstrate that the targeting of ERK1 could partially protect obese mice against insulin resistance and liver steatosis by decreasing adipose tissue inflammation and by increasing muscle glucose uptake. Our results indicate that deregulation of the ERK1 pathway could be an important component in obesity-associated metabolic disorders.


Assuntos
Resistência à Insulina/fisiologia , Leptina/deficiência , Proteína Quinase 3 Ativada por Mitógeno/deficiência , Obesidade/fisiopatologia , Animais , Fígado Gorduroso/genética , Fígado Gorduroso/metabolismo , Fígado Gorduroso/fisiopatologia , Feminino , Resistência à Insulina/genética , Leptina/genética , Masculino , Camundongos , Camundongos Knockout , Camundongos Obesos , Proteína Quinase 3 Ativada por Mitógeno/genética , Obesidade/genética
20.
Opt Lett ; 35(4): 583-5, 2010 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-20160825

RESUMO

We report the direct observation of the electromagnetic-field distribution of whispering gallery modes in silica microcavities (spheres and toroids). It is revealed by their excitation efficiency with a tapered fiber coupler swept along the meridian. The originality of this method lies in the use of the coupler itself for the near-field mapping, eliminating the need of additional tools used in previous work. This method is successfully applied to microspheres and microtoroids.

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