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1.
J Autoimmun ; 144: 103185, 2024 04.
Artículo en Inglés | MEDLINE | ID: mdl-38428109

RESUMEN

BACKGROUND: The significance of muscle biopsy as a diagnostic tool in idiopathic inflammatory myopathies (IIM) remains elusive. We aimed to determine the diagnostic weight that has been given to muscle biopsy in patients with suspected IIM, particularly in terms of clinical diagnosis and therapeutic decisions. MATERIAL AND METHODS: In this retrospective multicentric study, we analyzed muscle biopsy results of adult patients with suspected IIM referred to a tertiary center between January 1, 2007, and October 31, 2021. Information regarding referral department, suspected diagnosis, biopsy site, demographic, clinical, laboratory data, and imaging results were extracted. Statistical analyses included the level of agreement between suspected and histological diagnosis and calculation of diagnostic performance (positive and negative predictive values, positive and negative likelihood ratios, sensitivity, and specificity of muscle biopsy in relation to clinical diagnosis and/or treatment initiation). Performance was tested in different strata based on clinical pre-test probability. RESULTS: Among 758 muscle biopsies, IIM was histologically compatible in 357/758 (47.1%) cases. Proportion of IIM was higher if there was a solid clinical pre-test probability (64.3% vs. 42.4% vs. 48% for high, medium and low pre-test probability). Sensitivity and specificity of muscle biopsy were highest (82%) when the diagnosis by the clinician was used as outcome scenario. Negative predictive value was only moderate (between 63% and 80%) and lowest if autoantibodies were positive (35%). CONCLUSION: In patients with clinically suspected IIM, approximately 50% of biopsies revealed features indicative of IIM. Diagnostic performance of muscle biopsy was moderate to high depending on clinical pre-test probability.


Asunto(s)
Miositis , Adulto , Humanos , Estudios Retrospectivos , Miositis/diagnóstico , Miositis/patología , Biopsia , Toma de Decisiones Clínicas , Autoanticuerpos , Músculos
4.
Nano Lett ; 15(3): 1603-8, 2015 Mar 11.
Artículo en Inglés | MEDLINE | ID: mdl-25706329

RESUMEN

Fluorescence super-resolution microscopy showed correlated fluctuations of photoluminescence intensity and spatial localization of individual perovskite (CH3NH3PbI3) nanocrystals of size ∼200 × 30 × 30 nm(3). The photoluminescence blinking amplitude caused by a single quencher was a hundred thousand times larger than that of a typical dye molecule at the same excitation power density. The quencher is proposed to be a chemical or structural defect that traps free charges leading to nonradiative recombination. These trapping sites can be activated and deactivated by light.


Asunto(s)
Compuestos de Calcio/química , Compuestos de Calcio/efectos de la radiación , Cristalización/métodos , Mediciones Luminiscentes/métodos , Nanopartículas/química , Nanopartículas/efectos de la radiación , Óxidos/química , Óxidos/efectos de la radiación , Titanio/química , Titanio/efectos de la radiación , Absorción de Radiación , Luz , Ensayo de Materiales , Nanopartículas/ultraestructura , Tamaño de la Partícula
5.
Phys Chem Chem Phys ; 17(38): 24978-87, 2015 Oct 14.
Artículo en Inglés | MEDLINE | ID: mdl-26343504

RESUMEN

A light-induced photoluminescence (PL) enhancement in surface-deposited methylammonium lead iodide (CH3NH3PbI3) perovskites was investigated in detail using time-resolved luminescence microscopy. We found the PL intensity to increase up to three orders of magnitude upon light illumination with an excitation power density of 0.01-1 W cm(-2). The PL enhancement is accompanied by an increase of the PL lifetime from several nanoseconds to several hundred nanoseconds and also by an increase of the initial amplitude of the PL decay. The latter suggests excited state quenching at the subpicosecond timescale. We propose a model where the trapping sites responsible for non-radiative charge recombination can be de-activated by a photochemical reaction involving oxygen. The reaction zone is spatially limited by the excitation light-penetration depth and diffusion length of the charge carriers. The latter increases in the course of the light-curing process making the reaction zone spreading from the surface towards the interior of the crystal. The PL enhancement can be reversed by switching on/off the excitation light or switching the atmosphere between oxygen and nitrogen. Slow diffusion of the reactants and products and equilibrium between the active and "cured" trapping sites are proposed to be the reasons for peculiar responses of PL to such varied experimental conditions.

6.
Odontology ; 102(2): 297-302, 2014 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-23604464

RESUMEN

Evidence from epidemiologic studies suggests that periodontal diseases may exert a weak to moderate influence on the severity and course of coronary heart disease. The aim of this study was to investigate whether an association between chronic oral infections and the presence of an acute myocardial infarction (AMI) exists. A total of 248 patients after AMI and 249 healthy controls were recruited for this study. The oral assessment included caries frequency (DMFT indices), number of teeth, probing pocket depths, bleeding on probing, clinical attachment level, as well as radiographs to diagnose apical lesions. The medical examination included a blood analysis, e.g. the determination of the serum concentration of C-reactive protein (CRP). The data analysis showed statistically significant differences between AMI patients and the controls with regard to number of missing teeth (p = 0.001), DMFT index (p = 0.001) and presence of apical lesions of endodontic origin (p = 0.001). Logistic regression showed that the probability of having lesions of endodontic origin was with an odds ratio of 1.54 (95% CI 1.10-2.16; p = 0.012) considerably higher in the AMI patient group. Likewise, the AMI patients had with an odds ratio of 1.21 (95% CI 1.14-1.28; p < 0.001) a higher number of missing teeth. The data from the blood analysis, in particular the CRP values, showed no significant correlation with the number of apical lesions. The results of the present study underline that patients, who have experienced a myocardial infarction, had more missing teeth and a higher number of inflammatory processes, especially of endodontic origin, than healthy patients.


Asunto(s)
Infarto del Miocardio/complicaciones , Periodontitis/complicaciones , Anciano , Anciano de 80 o más Años , Proteína C-Reactiva/metabolismo , Estudios de Casos y Controles , Enfermedad Crónica , Femenino , Humanos , Masculino , Persona de Mediana Edad , Infarto del Miocardio/sangre , Periodontitis/sangre
7.
J Am Coll Cardiol ; 83(1): 47-59, 2024 01 02.
Artículo en Inglés | MEDLINE | ID: mdl-38171710

RESUMEN

BACKGROUND: The lack of disease-modifying drugs is one of the major unmet needs in patients with heart failure (HF). Peptides are highly selective molecules with the potential to act directly on cardiomyocytes. However, a strategy for effective delivery of therapeutics to the heart is lacking. OBJECTIVES: In this study, the authors sought to assess tolerability and efficacy of an inhalable lung-to-heart nano-in-micro technology (LungToHeartNIM) for cardiac-specific targeting of a mimetic peptide (MP), a first-in-class for modulating impaired L-type calcium channel (LTCC) trafficking, in a clinically relevant porcine model of HF. METHODS: Heart failure with reduced ejection fraction (HFrEF) was induced in Göttingen minipigs by means of tachypacing over 6 weeks. In a setting of overt HFrEF (left ventricular ejection fraction [LVEF] 30% ± 8%), animals were randomized and treatment was started after 4 weeks of tachypacing. HFrEF animals inhaled either a dry powder composed of mannitol-based microparticles embedding biocompatible MP-loaded calcium phosphate nanoparticles (dpCaP-MP) or the LungToHeartNIM only (dpCaP without MP). Efficacy was evaluated with the use of echocardiography, invasive hemodynamics, and biomarker assessment. RESULTS: DpCaP-MP inhalation restored systolic function, as shown by an absolute LVEF increase over the treatment period of 17% ± 6%, while reversing cardiac remodeling and reducing pulmonary congestion. The effect was recapitulated ex vivo in cardiac myofibrils from treated HF animals. The treatment was well tolerated, and no adverse events occurred. CONCLUSIONS: The overall tolerability of LungToHeartNIM along with the beneficial effects of the LTCC modulator point toward a game-changing treatment for HFrEF patients, also demonstrating the effective delivery of a therapeutic peptide to the diseased heart.


Asunto(s)
Insuficiencia Cardíaca , Animales , Enfermedad Crónica , Pulmón , Péptidos , Volumen Sistólico , Porcinos , Porcinos Enanos , Función Ventricular Izquierda
8.
J Dtsch Dermatol Ges ; 8(12): 990-8, 2010 Dec.
Artículo en Inglés, Alemán | MEDLINE | ID: mdl-20678148

RESUMEN

BACKGROUND: Our understanding of the pathogenic role of IgE in atopic dermatitis is incomplete. We asked whether blocking free IgE would alter the course of the disease. PATIENTS AND METHODS: We administered either omalizumab, a humanized monoclonal mouse antibody against IgE, or placebo subcutaneously for 16 weeks to 20 atopic dermatitis patients and measured immunological and clinical disease parameters. RESULTS: Omalizumab (I) reduced free serum IgE, (II) lowered surface IgE and FcɛRI expression on different peripheral blood mononuclear cells, (III) reduced the saturation of FcɛRI with IgE, (IV) increased the number of free FcɛRI and (V) lowered the number of IgE+, but not of FcɛRI+ cells in skin. The in vivo relevance of these results is evidenced by the increase in the threshold allergen concentration required to give a type I hypersensitivity reaction in the titrated skin test. While not significantly altering the clinical disease parameters, omalizumab treatment led to an improvement of the atopy patch test results in single patients, i.e. an eczematous reaction upon epicutaneous allergen challenge. CONCLUSIONS: The interference with immediate and delayed type skin tests may imply that a therapeutic benefit of omalizumab treatment, if present at all, would be seen in patients with acute rather than chronic forms of the disease.


Asunto(s)
Anticuerpos Monoclonales/administración & dosificación , Dermatitis Atópica/tratamiento farmacológico , Dermatitis Atópica/inmunología , Inmunoglobulina E/inmunología , Adolescente , Adulto , Antialérgicos/uso terapéutico , Anticuerpos Antiidiotipos , Anticuerpos Monoclonales Humanizados , Método Doble Ciego , Femenino , Humanos , Inyecciones Subcutáneas , Masculino , Persona de Mediana Edad , Omalizumab , Proyectos Piloto , Efecto Placebo , Pruebas Cutáneas , Resultado del Tratamiento , Adulto Joven
9.
J Invest Dermatol ; 139(12): 2417-2424.e2, 2019 12.
Artículo en Inglés | MEDLINE | ID: mdl-31229501

RESUMEN

Deposition of autoantibodies (α-BP180 and BP230) and complement along the dermal-epidermal-junction is a hallmark of bullous pemphigoid and was shown to be important for pathogenesis. Given the adverse effects of standard treatment (glucocorticoids, immunosuppressants), there is an unmet need for safe and effective therapies. In this phase 1 trial, we evaluated the safety and activity of BIVV009 (sutimlimab, previously TNT009), a targeted C1s inhibitor, in 10 subjects with active or past bullous pemphigoid (NCT02502903). Four weekly 60 mg/kg infusions of BIVV009 proved sufficient for inhibition of the classical complement pathway in all patients, as measured by CH50. C3c deposition along the dermal-epidermal junction was partially or completely abrogated in 4 of 5 patients, where it was present at baseline. BIVV009 was found to be safe and tolerable in this elderly population, with only mild to moderate adverse events reported (e.g., headache, fatigue). One serious adverse event (i.e., fatal cardiac decompensation) occurred at the end of the post-treatment observation period in an 84-year-old patient with a history of diabetes and heart failure, but was deemed unlikely to be related to the study drug. This trial provides the first results with a complement-targeting therapy in bullous pemphigoid, to our knowledge, and supports further studies on BIVV009's efficacy and safety in this population.


Asunto(s)
Autoantígenos/administración & dosificación , Complemento C3/metabolismo , Vía Clásica del Complemento/efectos de los fármacos , Dermis/patología , Distonina/administración & dosificación , Epidermis/patología , Colágenos no Fibrilares/administración & dosificación , Penfigoide Ampolloso/tratamiento farmacológico , Anciano , Anciano de 80 o más Años , Dermis/metabolismo , Epidermis/metabolismo , Femenino , Humanos , Infusiones Intravenosas , Masculino , Persona de Mediana Edad , Penfigoide Ampolloso/metabolismo , Penfigoide Ampolloso/patología , Colágeno Tipo XVII
10.
Aktuelle Urol ; 49(6): 500-508, 2018 Dec.
Artículo en Alemán | MEDLINE | ID: mdl-30522160

RESUMEN

INTRODUCTION: Virtual reality (VR) is an artificially simulated environment permitting interaction. On the other hand, augmented reality (AR) is an enhanced version of reality created by the use of technology to overlay digital information on an image of something being viewed through a device. Both technologies have partially been implemented in clinical daily routine. Surgical applications of VR and AR are currently evaluated. Yet it is still unclear which possibilities these new and versatile applications offer for physicians. INTENTION: The goal of this article was to assess current and future use of AR und VR, with a special focus on surgery. We also summarised obstacles for AR and VR use as well as potential clinical improvements through these new technologies. METHODS: Systematic literature research in PubMed with inclusion of reviews referring to AR and VR, especially focused on articles on surgery. Keywords were Augmented Reality, Virtual Reality, Telementoring and Telesurgery. Furthermore we briefly analysed the investment volume and investment strategy in medicine from the ten largest private technology companies of the USA. RESULTS: The keyword "Augmented Reality" leads to 1222 articles and 119 reviews, while "Virtual Reality" offered 7766 articles and 878 reviews. In recent years, the amount of published articles has increased. 45 articles were included. Multiple AR- and VR-applications are already integrated in surgical daily routine. The next promising applications will concern the possibility of intraoperative overlap with radiological imaging via AR-tools, as well as telementoring and the use of AR and VR in surgical and anatomical education. The expected - but unproven - advantages include cost savings, reduction in complications, comprehensive knowledge acquisition and improvement in surgical results. In addition, we notice enormous financial investment by technology companies in this sector. CONCLUSION: Due to their tremendous potential, AR and VR technologies will be increasingly integrated into surgery. However, the benefit of these new technologies for relevant endpoints are currently unclear. This should be examined in rigorous clinical trials. Physicians should play a key role in this technological revolution to exploit the potential of AR and VR for their patients.


Asunto(s)
Cirugía Asistida por Computador/métodos , Procedimientos Quirúrgicos Urológicos , Realidad Virtual , Humanos , Laparoscopía/métodos , Interfaz Usuario-Computador
11.
ChemSusChem ; 1(5): 417-24, 2008.
Artículo en Inglés | MEDLINE | ID: mdl-18702136

RESUMEN

Liquid transportation fuels must burn cleanly and have high energy densities, criteria that are currently fulfilled by petroleum, a non-renewable resource, the combustion of which leads to increasing levels of atmospheric CO(2). An attractive approach for the production of transportation fuels from renewable biomass resources is to convert carbohydrates into alkanes with targeted molecular weights, such as C(8)-C(15) for jet-fuel applications. Targeted n-alkanes can be produced directly from fructose by an integrated process involving first the dehydration of this C(6) sugar to form 5-hydroxymethylfurfural, followed by controlled formation of C-C bonds with acetone to form C(9) and C(15) compounds, and completed by hydrogenation and hydrodeoxygenation reactions to form the corresponding n-alkanes. Analogous reactions are demonstrated starting with 5-methylfurfural or 2-furaldehyde, with the latter leading to C(8) and C(13) n-alkanes.


Asunto(s)
Alcanos/química , Biomasa , Carbohidratos/química , Catálisis , Cetonas/química , Estructura Molecular , Peso Molecular , Temperatura , Agua/química
12.
J Dtsch Dermatol Ges ; 3(12): 974-8, 2005 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-16405713

RESUMEN

BACKGROUND: Patients with gluten sensitivity, i. e. celiac disease and dermatitis herpetiformis have anti-endomysial antibodies recognizing transglutaminases, which are usually detected on appropriate tissue sections. It would be desirable to have available a reliable, tissue-independent serological diagnostic tool. We compared disease-specificity and sensitivity of tTG versus eTG-based detection systems for the diagnosis of anti-endomysial IgA-antibodies. PATIENTS AND METHODS: We examined 204 serum samples in duplicates with commercial human ELISA-kits: 54 healthy blood donors, 20 celiac disease, 29 dermatitis herpetiformis and 101 with other autoimmune dermatoses. RESULTS: The tTG-based ELISA proved to be very disease-specific (100 %) and sensitive for the diagnosis of gluten sensitivity (95 % celiac disease; 96.6 % dermatitis herpetiformis). The eTG-based ELISA was also perfectly specific (100 %), but only 15 % of celiac disease-sera and 44.8 % of dermatitis herpetiformis-sera yielded positive results. CONCLUSIONS: The human tTG-ELISA fulfills all criteria of a screening test and, because of being investigator-independent, inexpensive and highly reproducible, compares favorably with the current diagnostic gold standard (indirect immunofluorescence and biopsy) of celiac disease and dermatitis herpetiformis. The low sensitivity of the eTG-ELISA may have technical reasons, but could theoretically also be linked to disease activity or indicate the existence of an as yet undefined disease subset. Studies are currently under way to address these issues.


Asunto(s)
Enfermedad Celíaca/sangre , Enfermedad Celíaca/diagnóstico , Dermatitis Herpetiforme/sangre , Dermatitis Herpetiforme/diagnóstico , Ensayo de Inmunoadsorción Enzimática/métodos , Transglutaminasas/sangre , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Autoantígenos/sangre , Biomarcadores/sangre , Enfermedad Celíaca/enzimología , Dermatitis Herpetiforme/enzimología , Femenino , Humanos , Masculino , Persona de Mediana Edad , Reproducibilidad de los Resultados , Sensibilidad y Especificidad
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