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BACKGROUND: Recent retrospective studies suggest a role for distinct microbiota in the perioperative morbidity and mortality of pancreatic head resections. OBJECTIVE: We aimed to prospectively investigate the microbial colonization of critical operative sites of pancreatic head resections to identify microbial stratification factors for surgical and long-term oncologic outcomes. METHODS: Prospective biomarker study applying 16S rRNA sequencing and microbial culturing to samples collected from various sites of the GI tract and surgical sites of patients during pancreatic head resections at a German single high-volume pancreatic center. RESULTS: A total of 101 patients were included (38 non-cancer, 63 cancer patients [50 PDAC patients]) in the study. In a first data analysis series, 16S rRNA sequencing data were utilized from 96 patients to assess associations of microbiome profiles with clinical parameters and outcomes. In general, microbiome composition varied according to sampling site, cancer, age or preoperative ERCP intervention, notably for the bile microbiome. In the PDAC subcohort, compositional variance of the bile or periampullary microbiome was significantly associated with postoperative complications such as ICU admission; on a taxonomic level we observed Enterococcus spp. to be significantly more abundant in patients developing deep or organ-space surgical site infections (SSI). Elevated Enterococcus relative abundances in the upper GI tract, in turn, were associated with 6-months mortality rates. In a second step, we focused on microbiological cultures collected from bile aspirates during surgery and investigated associations with perioperative complications and long-term survival. Notably, Enterococcus spp. were among the most prevalent pathobiont isolates observed in cancer patient bile specimens that were associated with severe SSIs, and thereby elevated mortality rates up to 24 months. Clinically relevant postoperative pancreatic fistulas or severe SSI were found as other major variables determining short-term mortality in this cancer patient cohort. In the context of adverse microbiological factors, a preoperative ERCP was also observed to segregate long-term survival, and it appeared to interact with the presence of Enterococcus spp. as highest mortality rates were observed in PDAC patients with both preoperative ERCP and presence of E. faecalis in bile aspirates. CONCLUSIONS: The presence of Enterococcus spp. in bile ducts of PDAC patients undergoing pancreatic surgery represents a significant risk factor for perioperative infections and, thereby, elevated postoperative and long-term mortality. This finding supports previous data on the use of the antibiotic drug piperacillin-tazobactam as appropriate perioperative antibiotic prophylaxis for preventing adverse outcomes after pancreatoduodenectomy.
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BACKGROUND: Currently available risk scores fail to accurately predict morbidity and mortality in patients with severe symptomatic aortic stenosis who undergo transcatheter aortic valve implantation (TAVI). In this context, biomarkers like matrix metalloproteinase-2 (MMP-2) and Galectin-3 (Gal-3) may provide additional prognostic information. METHODS: Patients with severe aortic stenosis undergoing consecutive, elective, transfemoral TAVI were included. Baseline demographic data, functional status, echocardiographic findings, clinical outcomes and biomarker levels were collected and analysed. RESULTS: The study cohort consisted of 89 patients (age 80.4 ± 5.1 years, EuroScore II 7.1 ± 5.8%). During a median follow-up period of 526 d, 28 patients (31.4%) died. Among those who died, median baseline MMP-2 (alive: 221.6 [170.4; 263] pg/mL vs. deceased: 272.1 [225; 308.8] pg/mL, p < 0.001) and Gal-3 levels (alive: 19.1 [13.5; 24.6] pg/mL vs. deceased: 25 [17.6; 29.5] pg/mL, p = 0.006) were higher than in survivors. In ROC analysis, MMP-2 reached an acceptable level of discrimination to predict mortality (AUC 0.733, 95% CI [0.62; 0.83], p < 0.001), but the predictive value of Gal-3 was poor (AUC 0.677, 95% CI [0.56; 0.79], p = 0.002). Kaplan-Meier and Cox regression analyses showed that patients with MMP-2 and Gal-3 concentrations above the median at baseline had significantly impaired long-term survival (p = 0.004 and p = 0.02, respectively). CONCLUSIONS: In patients with severe aortic stenosis undergoing transfemoral TAVI, MMP-2 and to a lesser extent Gal-3, seem to have additive value in optimizing risk prediction and streamlining decision-making.
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Estenose da Valva Aórtica , Biomarcadores , Galectina 3 , Metaloproteinase 2 da Matriz , Substituição da Valva Aórtica Transcateter , Humanos , Metaloproteinase 2 da Matriz/sangue , Substituição da Valva Aórtica Transcateter/mortalidade , Biomarcadores/sangue , Masculino , Feminino , Estenose da Valva Aórtica/cirurgia , Estenose da Valva Aórtica/mortalidade , Estenose da Valva Aórtica/sangue , Galectina 3/sangue , Idoso de 80 Anos ou mais , Idoso , Prognóstico , Galectinas , Proteínas Sanguíneas/análise , Proteínas Sanguíneas/metabolismoRESUMO
OBJECTIVES: Early tumor shrinkage (ETS) quantifies the objective response at the first assessment during systemic treatment. In metastatic colorectal cancer (mCRC), ETS gains relevance as an early available surrogate for patient survival. The aim of this study was to increase the predictive accuracy of ETS by using semi-automated volumetry instead of standard diametric measurements. METHODS: Diametric and volumetric ETS were retrospectively calculated in 253 mCRC patients who received 5-fluorouracil, leucovorin, and irinotecan (FOLFIRI) combined with either cetuximab or bevacizumab. The association of diametric and volumetric ETS with overall survival (OS) and progression-free survival (PFS) was compared. RESULTS: Continuous diametric and volumetric ETS predicted survival similarly regarding concordance indices (p > .05). In receiver operating characteristics, a volumetric threshold of 45% optimally identified short-term survivors. For patients with volumetric ETS ≥ 45% (vs < 45%), median OS was longer (32.5 vs 19.0 months, p < .001) and the risk of death reduced for the first and second year (hazard ratio [HR] = 0.25, p < .001, and HR = 0.39, p < .001). Patients with ETS ≥ 45% had a reduced risk of progressive disease only for the first 6 months (HR = 0.26, p < .001). These survival times and risks were comparable to those of diametric ETS ≥ 20% (vs < 20%). CONCLUSIONS: The accuracy of ETS in predicting survival was not increased by volumetric instead of diametric measurements. Continuous diametric and volumetric ETS similarly predicted survival, regardless of whether patients received cetuximab or bevacizumab. A volumetric ETS threshold of 45% and a diametric ETS threshold of 20% equally identified short-term survivors. KEY POINTS: ⢠ETS based on volumetric measurements did not predict survival more accurately than ETS based on standard diametric measurements. ⢠Continuous diametric and volumetric ETS predicted survival similarly in patients receiving FOLFIRI with cetuximab or bevacizumab. ⢠A volumetric ETS threshold of 45% and a diametric ETS threshold of 20% equally identified short-term survivors.
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Neoplasias do Colo , Neoplasias Colorretais , Neoplasias Retais , Humanos , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Bevacizumab/uso terapêutico , Camptotecina/uso terapêutico , Cetuximab/uso terapêutico , Neoplasias Colorretais/patologia , Intervalo Livre de Doença , Fluoruracila/uso terapêutico , Estudos RetrospectivosRESUMO
OBJECTIVES: To asses mid-term clinical outcomes of bioresorbable vascular scaffolds (BVS) for the treatment of coronary artery disease in a large-scale all-comers population. BACKGROUND: Several clinical settings are underrepresented in randomized studies investigating BVS against drug-eluting stents. Whether their results can be translated into the heterogeny patient population seen during daily routine requires further investigation. METHODS: The European ABSORB Consortium comprises the following European registries: GABI-R, ABSORB UK Registry, ABSORB France, BVS RAI Registry, and REPARA BVS Registry, which all prospectively collected patient-level data regarding outcomes following unrestricted BVS implantation. The primary endpoint of target lesion failure (TLF) includes cardiac death, target-vessel myocardial infarction (TVMI) and target-lesion revascularisation (TLR) at 12 months. The incidence of scaffold thrombosis (ST) according to ARC criteria was also assessed. Multivariable analysis was used to adjust for differences in patient and lesion characteristics. RESULTS: A total of 10,312 patients (mean age 58.4 ± 11.4 y) underwent BVS implantation during routine practice. The 12-month follow-up was complete in 95.5% of patients. At 12 months, the primary endpoint of TLF occurred in 3.6%; its components cardiac death, TVMI and TLR were documented in 1.2%, 1.8%, and 2.6%, respectively. The definite/probable ST rate was 1.7%. Absence of predilatation, discontinuation of DAPT and scaffold diameter below 3 mm were independent predictors of ST. CONCLUSIONS: The EAC demonstrates reasonable real-world clinical outcome data after BVS implantation. However, the rate of scaffold thrombosis remains high.
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Doença da Artéria Coronariana , Stents Farmacológicos , Intervenção Coronária Percutânea , Implantes Absorvíveis , Idoso , Doença da Artéria Coronariana/induzido quimicamente , Doença da Artéria Coronariana/diagnóstico por imagem , Doença da Artéria Coronariana/terapia , Everolimo/efeitos adversos , Humanos , Pessoa de Meia-Idade , Intervenção Coronária Percutânea/efeitos adversos , Desenho de Prótese , Alicerces Teciduais , Resultado do TratamentoRESUMO
BACKGROUND: Endoscopic vacuum therapy for the treatment of rectal anastomotic leak has been shown to be effective and safe. The majority of patients are treated after fecal diversion to avoid further septic complications. OBJECTIVE: To report the effectiveness of endoscopic vacuum therapy for rectal anastomotic leak without diversion compared to secondary stoma creation. DESIGN: Retrospective cohort analysis. SETTINGS: University hospital, single-center. PATIENTS: Patients undergoing sigmoid or rectal resection without fecal diversion during primary surgery who were treated with endoscopic vacuum therapy for clinically relevant anastomotic leak. MAIN OUTCOME MEASURES: Treatment success (sepsis control, granulation and closure of the leak cavity, and no subsequent interventional or surgical procedure required); treatment duration; complications associated with endoscopic vacuum therapy; outpatient treatment; and restoration of intestinal continuity in diverted patients. RESULTS: Fifty-seven patients were included. In 20 patients (35%), endoscopic vacuum therapy was initiated without secondary diversion since the leak was extraperitoneal, and the sponge could be placed into the leak cavity with an adequate seal toward the lumen. In 18 patients (90%), this approach was successful. None of these patients required subsequent diversion in the further course of their disease. In two patients, secondary diversion was necessary due to treatment failure. Balloon dilatation for luminal stenosis was required in two patients. When comparing patient and treatment characteristics of patients with and without a stoma, including treatment success and duration, no significant differences were found. Restoration of intestinal continuity was achieved in 69% of diverted patients. LIMITATIONS: Unrandomized, retrospective study design; confounding factors of treatment assignment; low patient numbers and short follow-up of diverted patients; and low statistical power. CONCLUSION: In this single-institution study, endoscopic vacuum therapy for rectal anastomotic leak was successful in 90% of patients without diversion with regard to sepsis control, granulation of the leak cavity, avoidance of surgery, and long-term stoma-free survival. See Video Abstract at http://links.lww.com/DCR/B737.TERAPIA ENDOSCÓPICA POR ASPIRACIÓN AL VACÍO EN CASOS DE FUGA ANASTOMÓTICA RECTO-CÓLICA IZQUIERDA SIN OSTOMÍA DE PROTECCIÓNANTECEDENTES:Se ha demostrado que la terapia endoscópica por aspiración al vacío en casos de fuga anastomótica recto-cólica izquierda en el tratamiento de la fuga anastomótica rectal es eficaz y segura. La mayoría de los casos beneficiaron del tratamiento después de la confeción de un ostomía de protección para evitar más complicaciones sépticas.OBJETIVO:Demostrar la efectividad de la terapia endoscópica por aspiración al vacío en casos de fuga anastomótica recto-cólica izquierda sin ostomía de protección comparada con los casos que tuvieron la creación de una ostomía secundaria.DISEÑO:Análisis de cohortes de tipo retrospectivo.AJUSTE:Hospital universitario, unicéntrico.PACIENTES:Aquellos pacientes sometidos a una resección sigmoidea o rectal sin ostomía de protección durante una cirugía primaria, y que fueron tratados con terapia endoscópica por aspiración al vacío en caso de fuga anastomótica clínicamente relevante.PRINCIPALES MEDIDAS DE RESULTADO:Tratamiento exitoso (control de la sepsis, granulación y cierre de la cavidad de la fuga, sin requerir procedimiento quirúrgico o intervención ulteterior); duración del tratamiento; complicaciones asociadas con la terapia endoscópica por aspiración al vacío; tratamiento ambulatorio; restablecimiento de la continuidad intestinal en los pacientes portadores de ostomía.RESULTADOS:Se incluyeron 57 pacientes. En 20 pacientes (35%), se inició la terapia endoscópica por aspiración al vacío sin derivación secundaria, ya que la fuga era extraperitoneal y la esponja podía colocarse en la cavidad de la fuga con un sellado adecuado hacia el lumen. En 18 pacientes (90%), este enfoque fue exitoso. Ninguno de estos pacientes requirió una derivación posterior durante la evolución de la enfermedad. En dos pacientes, fue necesaria una derivación secundaria debido al fracaso del tratamiento. Se requirió dilatación con balón por estenosis luminal en dos pacientes. Al comparar las características de los pacientes y del tratamiento con y sin ostomía, incluido el éxito y la duración del tratamiento, no se encontraron diferencias significativas. El restablecimiento de la continuidad intestinal se logró en el 69% de los pacientes derivados.LIMITACIONES:Diseño de estudio retrospectivo no aleatorio; factores de confusión en la asignación del tratamiento; escaso número de pacientes y seguimiento a corto plazo de los pacientes ostomizados; bajo poder estadístico.CONCLUSIÓN:En este estudio de una sola institución, la terapia al vacío por vía endoscópica en casos de fuga anastomótica rectal fue exitosa en el 90% de los pacientes sin derivación con respecto al control de la sepsis, granulación de la cavidad de la fuga, como se evitó la cirugía y la sobrevida sin ostomía a largo plazo. Consulte Video Resumen en http://links.lww.com/DCR/B737. (Traducción-Dr. Xavier Delgadillo).
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Fístula Anastomótica/terapia , Endoscopia do Sistema Digestório , Tratamento de Ferimentos com Pressão Negativa , Proctocolectomia Restauradora , Fístula Anastomótica/etiologia , Fístula Anastomótica/fisiopatologia , Fístula Anastomótica/cirurgia , Endoscopia do Sistema Digestório/instrumentação , Endoscopia do Sistema Digestório/métodos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Tratamento de Ferimentos com Pressão Negativa/instrumentação , Tratamento de Ferimentos com Pressão Negativa/métodos , Seleção de Pacientes , Proctocolectomia Restauradora/efeitos adversos , Proctocolectomia Restauradora/métodos , Doenças Retais/cirurgia , Reoperação/estatística & dados numéricos , Estudos Retrospectivos , Doenças do Colo Sigmoide/cirurgia , Resultado do TratamentoRESUMO
Corrosion is a major concern for many industries, as corrosive environments can induce structural and morphological changes that lead to material dissolution and accelerate material failure. The progression of corrosion depends on nanoscale morphology, stress, and defects present. Experimentally monitoring this complex interplay is challenging. Here we implement in situ Bragg coherent X-ray diffraction imaging (BCDI) to probe the dissolution of a Co-Fe alloy microcrystal exposed to hydrochloric acid (HCl). By measuring five Bragg reflections from a single isolated microcrystal at ambient conditions, we compare the full three-dimensional (3D) strain state before corrosion and the strain along the [111] direction throughout the corrosion process. We find that the strained surface layer of the crystal dissolves to leave a progressively less strained surface. Interestingly, the average strain closer to the centre of the crystal increases during the corrosion process. We determine the localised corrosion rate from BCDI data, revealing the preferential dissolution of facets more exposed to the acid stream, highlighting an experimental geometry effect. These results bring new perspectives to understanding the interplay between crystal strain, morphology, and corrosion; a prerequisite for the design of more corrosion-resistant materials.
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BACKGROUND: Non-resectability is common in patients with pancreatic ductal adenocarcinoma (PDAC) due to local invasion or distant metastases. Then, biliary or gastroenteric bypasses or both are often established despite associated morbidity and mortality. The current study explores outcomes after palliative bypass surgery in patients with non-resectable PDAC. METHODS: From the prospectively maintained German StuDoQ|Pancreas registry, all patients with histopathologically confirmed PDAC who underwent non-resective pancreatic surgery between 2013 and 2018 were retrospectively identified, and the influence of the surgical procedure on morbidity and mortality was analyzed. RESULTS: Of 389 included patients, 127 (32.6%) underwent explorative surgery only, and a biliary, gastroenteric or double bypass was established in 92 (23.7%), 65 (16.7%) and 105 (27.0%). After exploration only, patients had a significantly shorter stay in the intensive care unit (mean 0.5 days [SD 1.7] vs. 1.9 [3.6], 2.0 [2.8] or 2.1 [2.8]; P < 0.0001) and in the hospital (median 7 days [IQR 4-11] vs. 12 [10-18], 12 [8-19] or 12 [9-17]; P < 0.0001), and complications occurred less frequently (22/127 [17.3%] vs. 37/92 [40.2%], 29/65 [44.6%] or 48/105 [45.7%]; P < 0.0001). In multivariable logistic regression, biliary stents were associated with less major (Clavien-Dindo grade ≥ IIIa) complications (OR 0.49 [95% CI 0.25-0.96], P = 0.037), whereas-compared to exploration only-biliary, gastroenteric, and double bypass were associated with more major complications (OR 3.58 [1.48-8.64], P = 0.005; 3.50 [1.39-8.81], P = 0.008; 4.96 [2.15-11.43], P < 0.001). CONCLUSIONS: In patients with non-resectable PDAC, biliary, gastroenteric or double bypass surgery is associated with relevant morbidity and mortality. Although surgical palliation is indicated if interventional alternatives are inapplicable, or life expectancy is high, less invasive options should be considered.
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Carcinoma Ductal Pancreático , Neoplasias Pancreáticas , Humanos , Estudos Retrospectivos , Neoplasias Pancreáticas/patologia , Carcinoma Ductal Pancreático/cirurgia , Pâncreas/patologia , Cuidados Paliativos , Sistema de Registros , Neoplasias PancreáticasRESUMO
Break junctions in noble-metal films can exhibit electroluminescence (EL) through inelastic electron tunneling. The EL spectrum can be tuned by depositing a single-layer crystal of a transition-metal dichalcogenide (TMDC) on top. Whereas the emission from the gaps between silver or gold nanoparticles formed in the break junction is spectrally broad, the hybrid metal/TMDC structure shows distinct luminescence from the TMDC material. The EL from individual hotspots is found to be linearly polarized, with a polarization axis apparently oriented randomly. Surprisingly, the degree of polarization is retained in the EL from the TMDC monolayer at room temperature. In analogy to polarized photoluminescence experiments, such polarized EL can be interpreted as a signature of valley-selective transitions, suggesting that spin-flip transitions and dephasing for excitons in the K valleys are of limited importance. However, polarized EL may also originate from the metal nanoparticles formed under electromigration which constitute optical antenna structures. Such antennae can apparently change over time since jumps in the polarization are observed in bare silver-nanoparticle films. Remarkably, photon-correlation spectroscopy reveals that gold-nanoparticle films exhibit signatures of deterministic single-photon emission in the EL, suggesting a route to designing room-temperature polarized single-photon sources with tunable photon energy through the choice of TMDC overlayer.
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Focused ion beam (FIB) techniques are commonly used to machine, analyse and image materials at the micro- and nanoscale. However, FIB modifies the integrity of the sample by creating defects that cause lattice distortions. Methods have been developed to reduce FIB-induced strain; however, these protocols need to be evaluated for their effectiveness. Here, non-destructive Bragg coherent X-ray diffraction imaging is used to study the in situ annealing of FIB-milled gold microcrystals. Two non-collinear reflections are simultaneously measured for two different crystals during a single annealing cycle, demonstrating the ability to reliably track the location of multiple Bragg peaks during thermal annealing. The thermal lattice expansion of each crystal is used to calculate the local temperature. This is compared with thermocouple readings, which are shown to be substantially affected by thermal resistance. To evaluate the annealing process, each reflection is analysed by considering facet area evolution, cross-correlation maps of the displacement field and binarized morphology, and average strain plots. The crystal's strain and morphology evolve with increasing temperature, which is likely to be caused by the diffusion of gallium in gold below â¼280°C and the self-diffusion of gold above â¼280°C. The majority of FIB-induced strains are removed by 380-410°C, depending on which reflection is being considered. These observations highlight the importance of measuring multiple reflections to unambiguously interpret material behaviour.
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OBJECTIVES: The aim of this study was to evaluate very long-term results after unrestricted everolimus-eluting bioresorbable scaffolds (BRS) implantation. BACKGROUND: Previous randomized studies mainly included selected patients differing from those seen during daily routine and long-term data from all-comers registries are sparse. METHODS: Consecutive patients undergoing BRS implantation were included in this observational, single center study. Clinical follow-up was conducted up to 5 years. Endpoint of interest was the composite of target lesion failure (TLF), including target-vessel myocardial infarction and target lesion revascularization and cardiac death. Furthermore, ARC-defined scaffold thrombosis (ScT) were assessed. RESULTS: A total of 176 patients with a median age of 64 (55 - 72) years were analyzed, of which 59.6% presented an acute coronary syndrome. A total of 183 mainly complex lesions (55.8%) were treated. At 5 years, the rate for TLF was 21.6%. Definite or probable ScT rate was 4.1%. The rate of ScT within the first year was 2.8% and afterwards 1.2%. Notably, no ScT was seen later than 2 years. CONCLUSIONS: Although this real-world registry displays high rates of clinical events during long-term follow-up, no ScT was seen after 2 years.
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Doença da Artéria Coronariana , Stents Farmacológicos , Intervenção Coronária Percutânea , Implantes Absorvíveis , Idoso , Doença da Artéria Coronariana/diagnóstico por imagem , Doença da Artéria Coronariana/cirurgia , Everolimo/efeitos adversos , Seguimentos , Humanos , Pessoa de Meia-Idade , Intervenção Coronária Percutânea/efeitos adversos , Desenho de Prótese , Resultado do TratamentoRESUMO
BACKGROUND: Only laboratory-confirmed norovirus (NoV) cases have to be notified to the Robert Koch Institute (RKI) since 2011, but not other, e. g. clinical-epidemiological cases. It can be assumed that the extent of underreporting of NoV cases in Germany has significantly increased since then. OBJECTIVES: To discuss the extent of underreporting, we wanted to find out how many laboratory tests were carried out during gastroenteritis outbreaks. Furthermore, the significance of NoV outbreaks in occupational health is discussed. MATERIALS AND METHODS: Of all pseudonymized gastroenteritis outbreak data reported to 2 local health authorities between 2011 and 2015, the proportion of NoV outbreaks and reported cases of infection among employees in hospitals and community facilities (nursing homes for the elderly, day-care centers, schools) confirmed by laboratory tests was calculated retrospectively. RESULTS: Only a few gastroenteritis outbreaks in day-care centers were etiologically diagnosed, so that only 6% and less could be classified as NoV outbreaks. In nursing homes for the elderly, about half of the outbreaks were classified as NoV, in hospitals almost all of them. Employees accounted for up to 23% of those affected in NoV outbreaks. CONCLUSIONS: The low level of laboratory diagnostics carried out during gastroenteritis outbreaks in day-care centers suggests a considerable number of hidden NoV cases. The significant proportion of staff relative to the total number of infected persons during the outbreaks highlights the importance of the burden of NoV outbreaks as a topic in occupational health. Further, large-scale prospective studies are needed to empirically substantiate these initial findings.
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Norovirus , Saúde Pública , Idoso , Surtos de Doenças , Alemanha/epidemiologia , Humanos , Estudos Prospectivos , Estudos RetrospectivosRESUMO
Interventional cardiovascular medicine has seen constant progress over the last few decades. Since the first angiograms and percutaneous transluminal coronary angioplasty were carried out, this progress has been tremendous and has led to a substantial decline in cardiovascular morbidity and mortality. The purpose of this article is to report and review the latest developments and evidence in robotics-assisted percutaneous coronary intervention (rPCI) and its potential future applications, opportunities, and limitations. Contemporary evidence shows that rPCI can lead to a significant reduction in radiation exposure as well as medical hazards for cardiologists. Rates of device and procedural success remain high and there is no evidence of a disadvantage for the patient. The accuracy of implantation with a reduced geographic mismatch is a further advantage that can result in a higher quality of treatment. Even in complex coronary lesions and procedures, rPCI seems to be safe and efficient. The latest developments include telestenting over hundreds of kilometers from a remote platform. Currently, the main limitations are the absence of large-scale randomized trials for the valid assessment of the benefits and disadvantages of rPCI as well as the technical limitations of the currently available rPCI systems. rPCI is a forward-looking innovation in cardiology that is applicable to a wide range of coronary interventions. Despite the present lack of knowledge and the limited data concerning the outcome for the patient, the available literature reveals promising results that should lead to improvements for physicians and patients.
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Angioplastia Coronária com Balão , Doença da Artéria Coronariana , Intervenção Coronária Percutânea , Robótica , Doença da Artéria Coronariana/cirurgia , Humanos , StentsRESUMO
Intestinal cylindrical growth peaks in mice a few weeks after birth, simultaneously with crypt fission activity. It nearly stops after weaning and cannot be reactivated later. Transgenic mice expressing Cd97/Adgre5 in the intestinal epithelium develop a mega-intestine with normal microscopic morphology in adult mice. Here, we demonstrate premature intestinal differentiation in Cd97/Adgre5 transgenic mice at both the cellular and molecular levels until postnatal day 14. Subsequently, the growth of the intestinal epithelium becomes activated and its maturation suppressed. These changes are paralleled by postnatal regulation of growth factors and by an increased expression of secretory cell markers, suggesting growth activation of non-epithelial tissue layers as the origin of enforced tissue growth. To understand postnatal intestinal growth mechanistically, we study epithelial fate decisions during this period with the use of a 3D individual cell-based computer model. In the model, the expansion of the intestinal stem cell (SC) population, a prerequisite for crypt fission, is largely independent of the tissue growth rate and is therefore not spontaneously adaptive. Accordingly, the model suggests that, besides the growth activation of non-epithelial tissue layers, the formation of a mega-intestine requires a released growth control in the epithelium, enabling accelerated SC expansion. The similar intestinal morphology in Cd97/Adgre5 transgenic and wild type mice indicates a synchronization of tissue growth and SC expansion, likely by a crypt density-controlled contact inhibition of growth of intestinal SC proliferation. The formation of a mega-intestine with normal microscopic morphology turns out to originate in changes of autonomous and conditional specification of the intestinal cell fate induced by the activation of Cd97/Adgre5.
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Simulação por Computador , Mucosa Intestinal/crescimento & desenvolvimento , Intestino Delgado/crescimento & desenvolvimento , Modelos Biológicos , Receptores Acoplados a Proteínas G/metabolismo , Células-Tronco/metabolismo , Animais , Fator 4 Semelhante a Kruppel , Camundongos , Camundongos Transgênicos , Técnicas de Cultura de Órgãos , Receptores Acoplados a Proteínas G/genéticaRESUMO
Combining spatially resolved x-ray Laue diffraction with atomic-scale simulations, we observe how ion-irradiated tungsten undergoes a series of nonlinear structural transformations with increasing radiation exposure. Nanoscale defect-induced deformations accumulating above 0.02 displacements per atom (dpa) lead to highly fluctuating strains at â¼0.1 dpa, collapsing into a driven quasisteady structural state above â¼1 dpa. The driven asymptotic state is characterized by finely dispersed vacancy defects coexisting with an extended dislocation network and exhibits positive volumetric swelling, due to the creation of new crystallographic planes through self-interstitial coalescence, but negative lattice strain.
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OBJECTIVES: Globally, norovirus (NoV) is the leading cause of gastroenteritis infection among all ages. The development of prevention strategies in the field of occupational health requires a detailed knowledge about the impact of the disease on employees. This review article aims not only at evaluating the burden of NoV outbreaks on staff but also at discussing implications for future prevention strategies. METHODS: Published NoV outbreaks in Central and Northern Europe were identified via a systematic literature search. Additionally, published NoV outbreaks in Germany were detected via a manual literature search. Key epidemiological data, as the number of symptomatic staff, was then extracted. The proportion of affected employees was calculated for each dataset (single NoV outbreaks or aggregated data of multiple outbreaks). RESULTS: Overall, 116 datasets were extracted from 72 relevant articles. 144,852 persons were affected by NoV gastroenteritis, 25,408 out of them (17.5%) were employees. 23,874 (94.0%) of them fell sick during outbreaks in hospitals and related settings. NoV cases among personnel in food establishments were reported only sporadically (mean ratio: 0.01). CONCLUSIONS: Employees in hospitals and community facilities seem quantitatively to be most vulnerable towards NoV epidemics. Therefore, high quality of prevention measures in these settings, respective compliance with prevention strategies should have the highest priority. The disease can be considered as an occupational disease, even regularly without long-term consequences. Following work safety rules, a vaccination for vulnerable groups should be recommended if the vaccine development turns out to be successful.
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Infecções por Caliciviridae/epidemiologia , Surtos de Doenças/estatística & dados numéricos , Norovirus , Doenças Profissionais/epidemiologia , Europa (Continente)/epidemiologia , Serviços de Alimentação , Gastroenterite/epidemiologia , Gastroenterite/virologia , Pessoal de Saúde , Humanos , Doenças Profissionais/virologiaRESUMO
Single formamidinium lead bromide (FAPbBr3) perovskite nanocubes, approximately 10 nm in size, have extinction cross sections orders of magnitude larger than single dye molecules and can therefore be used to photoexcite one single dye molecule within their immediate vicinity by means of excitation-energy transfer (EET). The rate of photon emission by the single dye molecule is increased by 2 orders of magnitude under excitation by EET compared to direct excitation at the same laser fluence. Because the dye cannot accommodate biexcitons, NC biexcitons are filtered out by EET, giving rise to up to an order-of-magnitude improvement in the fidelity of photon antibunching. We demonstrate here that, contrary to expectation, energy transfer from the nanocrystal to dye molecules does not depend on the spectral line widths of the donor and acceptor and is therefore not governed by Förster's theory of resonance energy transfer (FRET). Two different cyanine dye acceptors with substantially different spectral overlaps with the nanocrystal donor show a similar light-harvesting capability. Cooling the sample from room temperature to 5 K reduces the average transition line widths 25-fold but has no apparent effect on the number of molecules emitting, i.e., on the spatial density of single dye molecules being photoexcited by single nanocrystals. Narrow zero-phonon lines are identified for both donor and acceptor, with an energetic separation of over 40 times the line width, implying a complete absence of spectral overlap-even though EET is evident. Both donor and acceptor exhibit spectral fluctuations, but no correlation is apparent between the jitter, which controls spectral overlap, and the overall light harvesting. We conclude that the energy transfer process is fundamentally nonresonant, implying effective energy dissipation in the perovskite donor because of strong electron-phonon coupling of the carriers comprising the exciton. The work highlights the importance of performing cryogenic spectroscopy to reveal the underlying mechanisms of energy transfer in complex donor-acceptor systems.
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Bragg coherent X-ray diffraction imaging (BCDI) is a non-destructive, lensless method for 3D-resolved, nanoscale strain imaging in micro-crystals. A challenge, particularly for new users of the technique, is accurate mapping of experimental data, collected in the detector reciprocal space coordinate frame, to more convenient orthogonal coordinates, e.g. attached to the sample. This is particularly the case since different coordinate conventions are used at every BCDI beamline. The reconstruction algorithms and mapping scripts composed for individual beamlines are not readily interchangeable. To overcome this, a BCDI experiment simulation with a plugin script that converts all beamline angles to a universal, right-handed coordinate frame is introduced, making it possible to condense any beamline geometry into three rotation matrices. The simulation translates a user-specified 3D complex object to different BCDI-related coordinate frames. It also allows the generation of synthetic coherent diffraction data that can be inserted into any BCDI reconstruction algorithm to reconstruct the original user-specified object. Scripts are provided to map from sample space to detector conjugated space, detector conjugated space to sample space and detector conjugated space to detector conjugated space for a different reflection. This provides the reader with the basis for a flexible simulation tool kit that is easily adapted to different geometries. It is anticipated that this will find use in the generation of tailor-made supports for phasing of challenging data and exploration of novel geometries or data collection modalities.
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PURPOSE: To investigate, whether cartilage repair surgery for focal osteochondral defects at the knee results in less degenerative changes over 6 years in a MR imaging follow-up than morphologically initially identical defects in non-operated control subjects from the osteoarthritis initiative (OAI). METHODS: A total of 32 individuals received baseline and follow-up MRI. In n = 16 patients with cartilage repair [osteochondral autograft transfer system (OATS), n = 12; spongiosa-augmented matrix-associated autologous chondrocyte implantation (MACI), n = 4] MRI was performed preoperatively and after 5.7 ± 2.3 year follow-up. Baseline MRIs of non-operated subjects from the OAI were screened for initially identical cartilage defects (n = 16). Morphological knee abnormalities were assessed using WORMS, AMADEUS and MOCART scores. A sagittal 2D MSME sequence was implemented for quantitative cartilage T2 relaxation time measurements in all (0, 2, 4, 6 and 8-years) follow-ups from the OAI and in the postoperative MRI protocol. RESULTS: For both groups, focal osteochondral defects were located at the femoral condyle in 8/16 cases (5 medial, 3 lateral) and at the patella in 8/16 cases. At baseline, the mean cartilage defect size ± SD was 1.4 ± 1.3 cm2 for the control group and 1.3 ± 1.2 cm2 for the cartilage repair group (n.s.). WORMS scores were not significantly different between the cartilage repair group and the control group at baseline [mean difference ± SEM (95%CI); 0.5 ± 2.5 (- 4.7, 5.7), n.s.]. During identical follow-up times, the progression of total WORMS scores [19.9 ± 2.3 (15.0, 24.9), P < 0.001] and of cartilage defects scores in the affected (P < 0.001) and in the opposing (P = 0.029) compartment was significantly more severe in non-operated individuals (P < 0.05). In non-operated subjects, T2 values increased continuously from baseline to the 8-year follow-up (P = 0.001). CONCLUSIONS: Patients with cartilage repair showed less progression of degenerative MRI changes at 6-year follow-up than a control cohort from the OAI with initially identical osteochondral defects. Patients with focal cartilage defects may profit from cartilage repair surgery since it may prevent progression of early osteoarthritis at the knee joint. LEVEL OF EVIDENCE: Prognostic study, Level II.
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Doenças das Cartilagens/cirurgia , Cartilagem Articular/transplante , Articulação do Joelho/cirurgia , Osteoartrite/cirurgia , Adulto , Doenças das Cartilagens/diagnóstico por imagem , Cartilagem Articular/diagnóstico por imagem , Estudos de Coortes , Progressão da Doença , Feminino , Fêmur/diagnóstico por imagem , Fêmur/cirurgia , Seguimentos , Humanos , Articulação do Joelho/diagnóstico por imagem , Estudos Longitudinais , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Procedimentos Ortopédicos , Osteoartrite/diagnóstico por imagem , Patela/diagnóstico por imagem , Patela/cirurgia , Estudos Prospectivos , Transplante Autólogo , Adulto JovemRESUMO
PURPOSE: To investigate the association of the presence and severity of diabetes mellitus (DM) with articular cartilage composition, using magnetic resonance imaging (MRI)-based T2 relaxation time measurements, and structural knee abnormalities. MATERIALS AND METHODS: In the Osteoarthritis Initiative 208, participants with DM (age 63.0 ± 8.9 years; 111 females) and risk factors for osteoarthritis (OA) or mild radiographic tibiofemoral OA (Kellgren-Lawrence [KL] grade ≤2) were identified and group-matched with 208 controls without DM (age 63.3 ± 9.1 years; 111 females). Subjects with diabetes-related renal or ophthalmological complications or insulin treatment at baseline (n = 50) were defined as severe DM. 3T MR images of the right knee were assessed for articular cartilage T2 , including texture and laminar analyses derived from the patella, medial, and lateral femur and tibia and for structural abnormalities using the modified whole-organ magnetic resonance imaging score (WORMS). Clustered linear regression analyses were used to assess associations of DM with MRI findings. RESULTS: DM subjects had significantly higher cartilage T2 in the patella (mean difference 0.92 msec [95% confidence interval (CI) 0.79, 1.06]; P = 0.001) and medial femur (mean difference 0.36 msec [95% CI 0.27, 0.81]; P = 0.006) compared to controls. Averaged over all compartments, DM subjects showed significantly higher texture parameters (variance, P = 0.001; contrast, P = 0.002; entropy, P < 0.001). Subjects with severe DM additionally showed higher T2 in the medial tibial deep and superficial layers (P = 0.011 and P = 0.041) compared to controls. No significant differences in cartilage, meniscus, and overall WORMS were found between the groups (P > 0.05). CONCLUSION: In comparison to nondiabetic controls, cartilage in DM subjects showed higher and more heterogeneous cartilage T2 values, indicating increased articular cartilage degeneration. This affected even more compartments in subjects with severe DM. LEVEL OF EVIDENCE: 2 Technical Efficacy: 5 J. Magn. Reson. Imaging 2018;47:380-390.
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Doenças das Cartilagens/complicações , Doenças das Cartilagens/diagnóstico por imagem , Complicações do Diabetes/diagnóstico por imagem , Imageamento por Ressonância Magnética/métodos , Osteoartrite do Joelho/complicações , Osteoartrite do Joelho/diagnóstico por imagem , Doenças das Cartilagens/patologia , Cartilagem Articular/diagnóstico por imagem , Cartilagem Articular/patologia , Estudos de Coortes , Complicações do Diabetes/patologia , Feminino , Humanos , Articulação do Joelho/diagnóstico por imagem , Articulação do Joelho/patologia , Estudos Longitudinais , Masculino , Pessoa de Meia-Idade , Osteoartrite do Joelho/patologia , Fatores de Risco , Índice de Gravidade de Doença , TempoRESUMO
OBJECTIVES: To assess the prognostic value of pre-therapeutic computed tomography (CT) attenuation of liver metastases for overall survival (OS) in metastatic colorectal cancer (mCRC). METHODS: In the open-label, randomised, prospective phase-III FIRE-3 trial, patients with histologically confirmed mCRC received fluorouracil (5-FU), leucovorin and irinotecan (FOLFIRI) with either cetuximab or bevacizumab. Participating patients gave written informed consent prior to study entry. In CT at baseline (portal venous phase, slice thickness ≤5 mm), mean attenuation [Hounsfield units (HU)] of liver metastases was retrospectively assessed by semi-automated volumetry. Its prognostic influence on OS was analysed in Kaplan-Meier-analysis and Cox proportional hazard regression and an optimal threshold was determined. RESULTS: In FIRE-3, 592 patients were enrolled between 2007 and 2012. Among the 347 patients eligible for liver volumetry, median baseline CT attenuation of liver metastases was 59.67 HU [interquartile range (IQR), 49.13, 68.85]. Increased attenuation was associated with longer OS {per 10 HU: hazard ratio (HR), 0.85 [95% confidence interval (CI), 0.78, 0.93], p < 0.001}. The optimised threshold (≥61.62 HU) was a strong predictor for increased OS [median, 21.3 vs 30.6 months; HR, 0.61 (95% CI, 0.47, 0.80), p < 0.001]. Multivariate regression controlling for correlated and further prognostic factors confirmed this [HR, 0.60 (95% CI, 0.45, 0.81), p = 0.001]. Furthermore, mean attenuation ≥61.62 HU was significantly associated with increased early tumour shrinkage (p = 0.002) and increased depth of response (p = 0.012). CONCLUSIONS: Increased mean baseline CT attenuation of liver metastases may identify mCRC patients with prolonged OS and better tumour response. KEY POINTS: ⢠In colorectal cancer, increased attenuation of liver metastases in baseline computed tomography is a prognostic factor for prolonged OS (p < 0.001). ⢠A threshold of ≥61.62 HU was determined as optimal cut-off to identify patients with prolonged OS (p < 0.001), early tumour shrinkage (p = 0.002) and increased depth of response (p = 0.012).