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1.
Nature ; 561(7723): 363-367, 2018 09.
Artículo en Inglés | MEDLINE | ID: mdl-30188496

RESUMEN

High-energy particle accelerators have been crucial in providing a deeper understanding of fundamental particles and the forces that govern their interactions. To increase the energy of the particles or to reduce the size of the accelerator, new acceleration schemes need to be developed. Plasma wakefield acceleration1-5, in which the electrons in a plasma are excited, leading to strong electric fields (so called 'wakefields'), is one such promising acceleration technique. Experiments have shown that an intense laser pulse6-9 or electron bunch10,11 traversing a plasma can drive electric fields of tens of gigavolts per metre and above-well beyond those achieved in conventional radio-frequency accelerators (about 0.1 gigavolt per metre). However, the low stored energy of laser pulses and electron bunches means that multiple acceleration stages are needed to reach very high particle energies5,12. The use of proton bunches is compelling because they have the potential to drive wakefields and to accelerate electrons to high energy in a single acceleration stage13. Long, thin proton bunches can be used because they undergo a process called self-modulation14-16, a particle-plasma interaction that splits the bunch longitudinally into a series of high-density microbunches, which then act resonantly to create large wakefields. The Advanced Wakefield (AWAKE) experiment at CERN17-19 uses high-intensity proton bunches-in which each proton has an energy of 400 gigaelectronvolts, resulting in a total bunch energy of 19 kilojoules-to drive a wakefield in a ten-metre-long plasma. Electron bunches are then injected into this wakefield. Here we present measurements of electrons accelerated up to two gigaelectronvolts at the AWAKE experiment, in a demonstration of proton-driven plasma wakefield acceleration. Measurements were conducted under various plasma conditions and the acceleration was found to be consistent and reliable. The potential for this scheme to produce very high-energy electron bunches in a single accelerating stage20 means that our results are an important step towards the development of future high-energy particle accelerators21,22.

2.
BMC Health Serv Res ; 23(1): 1095, 2023 Oct 12.
Artículo en Inglés | MEDLINE | ID: mdl-37828553

RESUMEN

INTRODUCTION: Effective leadership and management (L&M) are essential to the success of health care organizations. Young medical leaders often find themselves ill-prepared to take on these new responsibilities, but rarely attend training in L&M skills. The aims of this study were to evaluate physician's self-perceived competencies and training needs for L&M, to identify available regional L&M training, and to highlight opportunities, challenges and threats regarding physicians' training in medical L&M in the French-speaking part of Switzerland. METHODS: We conducted a mixed methods study in three steps: (1) a survey on perceived L&M competencies and training needs (5 dimensions) to all physicians of a Swiss University Hospital (N = 2247); (2) a mapping of the Swiss French speaking L&M training programs through analysis of hospital websites and interviews; and (3) semi-structured interviews with L&M program coordinators about the programs' strengths and weaknesses as well as the opportunities and challenges to include physicians in such training. We used analysis of variance to compare differences in perceived competences between physicians of different hierarchical status and used Cramer's V to measure the association's degree between physicians' training needs and prior training in L&M and hierarchical status. We analysed semi-structured interviews using thematic analysis. RESULTS: Five-hundred thirty-two physicians responded (24%). Physicians perceived themselves as rather competent in most leadership dimensions. More experienced physicians reported a higher sense of competence in all dimensions of leadership (e.g. Working with others: F = 15.55, p < .001; Managing services: F = 46.89, p < .001). Three competencies did not vary according to the hierarchical status: emotional intelligence (F = 1.56, p = .20), time management (F = 0.47, p = .70) and communicating (F = 1.97, p = .12). There was a weak to moderate association between the responders' self-perceived needs for training and their hierarchal status for all competencies (Cramer's V ∈ [0.16;0.35]). Physicians expressed a strong desire to seek out training for all competencies, especially for knowing one's leadership style (82%), managing teams (83%), and managing conflict (85%). Although existing local L&M training programs covered most relevant topics, only a forth of responders had attended any type of training. L&M program coordinators identified several facilitators and barriers to physician attendance on institutional (matching reality and training), relational (managing collective intelligence), and individual levels (beliefs and self-perceived identity). CONCLUSIONS: French-speaking Swiss hospital physicians clearly express training needs for L&M skills although they only rarely attend such training programs. Reasons for non-attendance to such programs should be explored in order to understand physicians' low participation rates in these trainings.


Asunto(s)
Liderazgo , Médicos , Humanos , Suiza , Competencia Profesional , Competencia Clínica
3.
Phys Rev Lett ; 129(2): 024802, 2022 Jul 08.
Artículo en Inglés | MEDLINE | ID: mdl-35867433

RESUMEN

A long, narrow, relativistic charged particle bunch propagating in plasma is subject to the self-modulation (SM) instability. We show that SM of a proton bunch can be seeded by the wakefields driven by a preceding electron bunch. SM timing reproducibility and control are at the level of a small fraction of the modulation period. With this seeding method, we independently control the amplitude of the seed wakefields with the charge of the electron bunch and the growth rate of SM with the charge of the proton bunch. Seeding leads to larger growth of the wakefields than in the instability case.

4.
Phys Rev Lett ; 126(16): 164802, 2021 Apr 23.
Artículo en Inglés | MEDLINE | ID: mdl-33961468

RESUMEN

We use a relativistic ionization front to provide various initial transverse wakefield amplitudes for the self-modulation of a long proton bunch in plasma. We show experimentally that, with sufficient initial amplitude [≥(4.1±0.4) MV/m], the phase of the modulation along the bunch is reproducible from event to event, with 3%-7% (of 2π) rms variations all along the bunch. The phase is not reproducible for lower initial amplitudes. We observe the transition between these two regimes. Phase reproducibility is essential for deterministic external injection of particles to be accelerated.

5.
Phys Rev Lett ; 125(26): 264801, 2020 Dec 31.
Artículo en Inglés | MEDLINE | ID: mdl-33449727

RESUMEN

We study experimentally the effect of linear plasma density gradients on the self-modulation of a 400 GeV proton bunch. Results show that a positive or negative gradient increases or decreases the number of microbunches and the relative charge per microbunch observed after 10 m of plasma. The measured modulation frequency also increases or decreases. With the largest positive gradient we observe two frequencies in the modulation power spectrum. Results are consistent with changes in wakefields' phase velocity due to plasma density gradients adding to the slow wakefields' phase velocity during self-modulation growth predicted by linear theory.

6.
Phys Rev Lett ; 122(5): 054802, 2019 Feb 08.
Artículo en Inglés | MEDLINE | ID: mdl-30822008

RESUMEN

We give direct experimental evidence for the observation of the full transverse self-modulation of a long, relativistic proton bunch propagating through a dense plasma. The bunch exits the plasma with a periodic density modulation resulting from radial wakefield effects. We show that the modulation is seeded by a relativistic ionization front created using an intense laser pulse copropagating with the proton bunch. The modulation extends over the length of the proton bunch following the seed point. By varying the plasma density over one order of magnitude, we show that the modulation frequency scales with the expected dependence on the plasma density, i.e., it is equal to the plasma frequency, as expected from theory.

7.
Phys Rev Lett ; 122(5): 054801, 2019 Feb 08.
Artículo en Inglés | MEDLINE | ID: mdl-30822039

RESUMEN

We measure the effects of transverse wakefields driven by a relativistic proton bunch in plasma with densities of 2.1×10^{14} and 7.7×10^{14} electrons/cm^{3}. We show that these wakefields periodically defocus the proton bunch itself, consistently with the development of the seeded self-modulation process. We show that the defocusing increases both along the bunch and along the plasma by using time resolved and time-integrated measurements of the proton bunch transverse distribution. We evaluate the transverse wakefield amplitudes and show that they exceed their seed value (<15 MV/m) and reach over 300 MV/m. All these results confirm the development of the seeded self-modulation process, a necessary condition for external injection of low energy and acceleration of electrons to multi-GeV energy levels.

8.
World J Urol ; 37(7): 1369-1375, 2019 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-30288598

RESUMEN

PURPOSE: Aquablation of the prostate using the AquaBeam™ system promises equivalent functional outcomes, reduced learning curve, and improved sexual function compared to transurethral prostate resection as shown in prospective randomized trials. This prospective cohort study aims to evaluate if published results can be transferred into the clinical routine in a non-selected patient collective. METHODS: This study includes all patients treated between September 2017 and June 2018 with Aquablation of the prostate. Patients have been evaluated prospectively for the perioperative course and early follow-up. Besides voiding parameter and symptom score, TRUS-volume change, ejaculatory function, and adverse events have been recorded. RESULTS: 118 consecutive patients have been treated in the given time. Aquablation could be carried out successfully in all patients. IPSS, QoL, Qmax, and PVR improved significantly after the procedure and continued to improve during 3-month follow-up. Mean OR time was 20 min, TRUS volume decreased by 65%, and 73% of the patients retained antegrade ejaculation. Thirteen adverse events (> Clavien-Dindo I) occurred in 10 patients. CONCLUSION: The surgical ablation of the prostate using Aquablation achieved significant and immediate improvement of functional voiding parameters Qmax and PVR as well as symptomatic improvement of IPSS and QoL. Aquablation seems to be safe and effective with a low perioperative complication profile even in a non-selected group of patients.


Asunto(s)
Técnicas de Ablación/métodos , Hiperplasia Prostática/cirugía , Resección Transuretral de la Próstata/métodos , Obstrucción Uretral/cirugía , Agua , Anciano , Anciano de 80 o más Años , Estudios de Cohortes , Humanos , Masculino , Persona de Mediana Edad , Complicaciones Posoperatorias/epidemiología , Hiperplasia Prostática/complicaciones , Disfunciones Sexuales Fisiológicas/epidemiología , Resultado del Tratamiento , Obstrucción Uretral/etiología
9.
Philos Trans A Math Phys Eng Sci ; 377(2151): 20180418, 2019 Aug 12.
Artículo en Inglés | MEDLINE | ID: mdl-31230571

RESUMEN

In this article, we briefly summarize the experiments performed during the first run of the Advanced Wakefield Experiment, AWAKE, at CERN (European Organization for Nuclear Research). The final goal of AWAKE Run 1 (2013-2018) was to demonstrate that 10-20 MeV electrons can be accelerated to GeV energies in a plasma wakefield driven by a highly relativistic self-modulated proton bunch. We describe the experiment, outline the measurement concept and present first results. Last, we outline our plans for the future. This article is part of the Theo Murphy meeting issue 'Directions in particle beam-driven plasma wakefield acceleration'.

10.
J Microsc ; 266(2): 115-125, 2017 05.
Artículo en Inglés | MEDLINE | ID: mdl-28267878

RESUMEN

The mechanical cell environment is a key regulator of biological processes . In living tissues, cells are embedded into the 3D extracellular matrix and permanently exposed to mechanical forces. Quantification of the cellular strain state in a 3D matrix is therefore the first step towards understanding how physical cues determine single cell and multicellular behaviour. The majority of cell assays are, however, based on 2D cell cultures that lack many essential features of the in vivo cellular environment. Furthermore, nondestructive measurement of substrate and cellular mechanics requires appropriate computational tools for microscopic image analysis and interpretation. Here, we present an experimental and computational framework for generation and quantification of the cellular strain state in 3D cell cultures using a combination of 3D substrate stretcher, multichannel microscopic imaging and computational image analysis. The 3D substrate stretcher enables deformation of living cells embedded in bead-labelled 3D collagen hydrogels. Local substrate and cell deformations are determined by tracking displacement of fluorescent beads with subsequent finite element interpolation of cell strains over a tetrahedral tessellation. In this feasibility study, we debate diverse aspects of deformable 3D culture construction, quantification and evaluation, and present an example of its application for quantitative analysis of a cellular model system based on primary mouse hepatocytes undergoing transforming growth factor (TGF-ß) induced epithelial-to-mesenchymal transition.


Asunto(s)
Técnicas de Cultivo de Célula/métodos , Hepatocitos/citología , Hepatocitos/fisiología , Imagenología Tridimensional/métodos , Microscopía/métodos , Estrés Mecánico , Animales , Transición Epitelial-Mesenquimal , Hidrogel de Polietilenoglicol-Dimetacrilato , Ratones
11.
Methods ; 76: 27-34, 2015 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-25461776

RESUMEN

Isothermal microcalorimetry measures the heat released or consumed by physical or chemical processes. Metabolic activity releases heat that can be measured. However the calorimetric signal can be difficult for new users to interpret. This paper compares microcalorimetry to other techniques and reviews its application to different fields where microbiological activity is important. We also describe different ways to analyze the data and translate it into meaningful (micro)biological equivalents. This paper aims at providing non-specialist reader the tools to understand how isothermal microcalorimetry can be used for microbiological applications.


Asunto(s)
Bacterias/crecimiento & desarrollo , Calorimetría/métodos , Bacterias/metabolismo , Calor
13.
Eur Arch Otorhinolaryngol ; 272(12): 3693-703, 2015 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-25527412

RESUMEN

Higher levels of fibrinogen or cholesterol were associated with improved hearing recovery in SSHL patients after treatment with HELP-apheresis (Heparin-induced extracorporeal LDL precipitation apheresis). The present trial was performed to demonstrate HELP-related effects on relevant metabolic and inflammatory parameters in the context of SSHL treatment. In the framework of a single arm non-controlled trial, we investigated the variation of metabolic and inflammatory parameters using HELP-apheresis for a defined group of 100 patients with SSHL. Based on cut off inclusion criteria (Serum LDL-cholesterol >1.6 g/l and/or fibrinogen >2.0 g/l, SSHL in minimum three frequencies more than 30 dB, time after event not longer than 6 days), the protocol followed a strict time line with one single shot HELP-apheresis and follow-up monitoring including laboratory parameters at six defined time points. If HELP-apheresis could not effect improvement of hearing on day 5, additional corticosteroid treatment was applied. Concentration of anti-inflammatory IL-10 increased while other proinflammatory parameters declined. Serum levels of all measured sterols and apolipoproteins decreased significantly. None of the investigated parameters were suitable to predict hearing improvement of the patients. Levels of fibrinogen and LDL-cholesterol were not prognostic for outcome after HELP-apheresis. A significant (p < 0.001) increase of anti-inflammatory IL-10 after apheresis was notable, while most of the proinflammatory parameters declined. Despite the limited validity of a single arm non-controlled trial, these alterations on immune modulating factors indicate possible secondary pleiotropic effects caused by HELP-apheresis.


Asunto(s)
Eliminación de Componentes Sanguíneos/métodos , Fibrinógeno/análisis , Pérdida Auditiva Sensorineural/terapia , Pérdida Auditiva Súbita/terapia , Adulto , Anciano , Anciano de 80 o más Años , Anticoagulantes/uso terapéutico , LDL-Colesterol/sangre , Circulación Extracorporea , Femenino , Heparina/uso terapéutico , Humanos , Interleucina-10/sangre , Masculino , Persona de Mediana Edad , Pronóstico , Estudios Prospectivos , Adulto Joven
14.
Z Gerontol Geriatr ; 48(8): 677-90, 2015 Dec.
Artículo en Alemán | MEDLINE | ID: mdl-26582461

RESUMEN

BACKGROUND: Although the need for interdisciplinary research is generally accepted in gerontology, such interdisciplinary communication is often limited to various combinations of psychological, sociological and biomedical scientific approaches. We argue that gerontology requires a continuous examination of novel disciplinary constellations to obtain a better understanding of aging in its complexity and to further develop this scientific field in its entirety. OBJECTIVE: The present study introduced and tested for the first time an innovative disciplinary trialogue, i.e. the combination of psychology, theology and diaconal studies. In particular, it is assumed that this combination can contribute to a more profound interpretation of the prominent concept of structural lag which is underresearched in gerontology. MATERIAL AND METHODS: The analysis of structural lag with another overarching concept, "room for possibilities", can provide a synergy-rich interpretation category for a range of challenges connected with old age. In this respect, three major transitions were selected to shed light on these concepts and examined by means of three focus group interviews: transition to retirement, need for long-term care in the private home context and transition to nursing home life. The data were evaluated using qualitative content analysis. RESULTS: The interdisciplinary-oriented evaluation of the interviews and the qualitative data analysis revealed the relevance of different perceptions of time in all three transitions. In addition, different dynamics in terms of the interplay of gains and losses as well as participation were found to be important for a better understanding of the three transitions. In particular, the subjective interpretation of the time remaining for living and the predetermined or self-selected time structuring of the daily routine were important factors for the perception of one's own potential. The results also underline a range of unused room for possibilities and the existence of structural lag for each transition. CONCLUSION: By the cooperation of the participating disciplines aspects of aging and their interdependence became visible. At the same time this pilot-like disciplinary trialogue revealed the challenges in combining interdisciplinary perspectives by the combination of empirical and hermeneutical methods.


Asunto(s)
Servicios de Salud para Ancianos/organización & administración , Grupo de Atención al Paciente/organización & administración , Psicología/organización & administración , Servicio Social/organización & administración , Teología , Atención a la Salud/organización & administración , Alemania , Modelos Organizacionales , Proyectos Piloto
15.
Br J Cancer ; 111(2): 213-9, 2014 Jul 15.
Artículo en Inglés | MEDLINE | ID: mdl-25003663

RESUMEN

BACKGROUND: Pelvic lymph node dissection in patients undergoing radical prostatectomy for clinically localised prostate cancer is not without morbidity and its therapeutical benefit is still a matter of debate. The objective of this study was to develop a model that allows preoperative determination of the minimum number of lymph nodes needed to be removed at radical prostatectomy to ensure true nodal status. METHODS: We analysed data from 4770 patients treated with radical prostatectomy and pelvic lymph node dissection between 2000 and 2011 from eight academic centres. For external validation of our model, we used data from a cohort of 3595 patients who underwent an anatomically defined extended pelvic lymph node dissection. We estimated the sensitivity of pathological nodal staging using a beta-binomial model and developed a novel clinical (preoperative) nodal staging score (cNSS), which represents the probability that a patient has lymph node metastasis as a function of the number of examined nodes. RESULTS: In the development and validation cohorts, the probability of missing a positive lymph node decreases with increase in the number of nodes examined. A 90% cNSS can be achieved in the development and validation cohorts by examining 1-6 nodes in cT1 and 6-8 nodes in cT2 tumours. With 11 nodes examined, patients in the development and validation cohorts achieved a cNSS of 90% and 80% with cT3 tumours, respectively. CONCLUSIONS: Pelvic lymph node dissection is the only reliable technique to ensure accurate nodal staging in patients treated with radical prostatectomy for clinically localised prostate cancer. The minimum number of examined lymph nodes needed for accurate nodal staging may be predictable, being strongly dependent on prostate cancer characteristics at diagnosis.


Asunto(s)
Neoplasias de la Próstata/patología , Anciano , Anciano de 80 o más Años , Estudios de Cohortes , Humanos , Escisión del Ganglio Linfático , Metástasis Linfática , Masculino , Persona de Mediana Edad , Estadificación de Neoplasias , Prostatectomía , Neoplasias de la Próstata/cirugía , Medición de Riesgo
16.
Nutr Metab Cardiovasc Dis ; 24(9): 1027-34, 2014 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-24813306

RESUMEN

BACKGROUND AND AIMS: The adipokine adipocyte fatty acid binding protein (AFABP) is positively associated with the development of the metabolic syndrome, diabetes mellitus, and cardiovascular disease. We hypothesized that AFABP also increases with deteriorating renal function. METHODS AND RESULTS: Serum AFABP levels were quantified by enzyme linked immunosorbent assay in 532 patients with chronic kidney disease (CKD) covering the whole spectrum of estimated glomerular filtration rate (eGFR) categories from G1 to G5 (study population 1). Furthermore, AFABP was measured in 32 patients before and within 30 h after elective unilateral nephrectomy, a model of acute kidney dysfunction (AKD) (study population 2). Moreover, circulating AFABP was investigated in rats undergoing bilateral nephrectomy (BNE) as compared to sham-operated animals. Median serum AFABP levels adjusted for age, gender, and body mass index significantly increased with increasing eGFR category (G1: 22.0 µg/l; G2: 34.6 µg/l; G3: 56.7 µg/l; G4: 95.2 µg/l; and G5: 173.9 µg/l). Furthermore, renal dysfunction remained positively associated with AFABP in multivariate analysis in this cohort. In patients undergoing unilateral nephrectomy, AFABP increased significantly after surgery (42.1 µg/l) as compared to pre-surgical values (29.3 µg/l). Furthermore, relative changes of post-to-pre-surgical AFABP levels were independently associated with relative changes of post-to-pre-surgical creatinine concentrations. After BNE in rats, AFABP increased significantly as compared to sham-operated animals. CONCLUSIONS: We show that AFABP is significantly elevated in CKD and AKD patients. Furthermore, measures of renal function are associated with circulating AFABP. Moreover, animal experiments indicate that AFABP levels strongly depend on renal function.


Asunto(s)
Lesión Renal Aguda/sangre , Adipocitos/metabolismo , Proteínas de Unión a Ácidos Grasos/sangre , Insuficiencia Renal Crónica/sangre , Adipoquinas/sangre , Adulto , Anciano , Anciano de 80 o más Años , Animales , Índice de Masa Corporal , Creatinina/sangre , Estudios Transversales , Femenino , Tasa de Filtración Glomerular , Humanos , Masculino , Persona de Mediana Edad , Análisis Multivariante , Nefrectomía , Ratas , Adulto Joven
17.
Facts Views Vis Obgyn ; 16(2): 185-193, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38950532

RESUMEN

Background: Abdominal hysterectomy has been largely replaced by minimally invasive surgery. Nevertheless, in some situations, a minimally invasive intervention must be converted to laparotomy. Factors associated with conversion to laparotomy are still a matter of debate. Objective: The aim of this study was to evaluate the clinicopathological factors associated with the conversion of laparoscopic hysterectomy to laparotomy. Materials and Methods: The risk factors for conversion of a preplanned laparoscopic procedure to laparotomy were retrospectively evaluated in 441 patients undergoing a hysterectomy for a benign indication between 2016 and 2020. Associations between the clinical factors were analysed using Pearson's chi-square and Fisher's exact test, and predictive values for conversion were assessed through multivariate logistic regression. Result: Conversion occurred in 32 (7.3%) of the cases. Significant differences were detected for uterus weight (576.9gr vs 174.6gr, p<0.001), myoma size (7.0 cm vs. 1.8 cm, p<0.001), and presence of triple diagnosis consisting of leiomyoma, adenomyosis uteri, and pathological adnexal findings (p<0.013). The conversion resulted in prolonged surgery time (181.6 min vs. 119.6 min, p<0.001) and hospital stay (4.0 vs. 3.1 days, p<0.001), as well as an increased rate of wound infection (15.6% vs. 3.4%, p<0.001). A 10g increase in uterus weight raised the risk of conversion by 7.0%, and a 1cm increase in myoma diameter by 7.3%, while adnexal pathologies and extensive adhesions increased the odds of conversion to laparotomy threefold (ORs of 3.2, 1.09-9.6 and 3.6, 1.3-10.0, respectively). Conclusion: Uterus weight, myoma size, the coexistence of pathological adnexal findings, and non-physiological adhesions are independent risk factors for conversion. What is new?: This study provides data regarding the risk and factors increasing this risk for conversion to laparotomy during laparoscopic hysterectomy.

18.
World J Urol ; 31(6): 1427-32, 2013 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-23358791

RESUMEN

PURPOSE: To describe the incidence and drug susceptibility profiles of uropathogenic extended-spectrum-ß-lactamase-producing Escherichia coli (ESBL-EC) during a 10-year period and to identify differences in resistance patterns between urological and non-urological ESBL-EC isolates. METHODS: Retrospective analysis of 191,564 urine samples obtained during 2001 to 2010 at the University Hospital Basel, Switzerland. The computerized database of the Clinical Microbiology Laboratory and the Division of Infectious Diseases and Hospital Epidemiology was used to identify ESBL-EC positive urine samples. ESBL-EC isolates were stratified according their origin into two groups: Urology and non-Urology isolates. RESULTS: The rate of ESBL-EC positive urine samples increased significantly during the study period (3 in 2001 compared to 55 in 2010, p < 0.05). The most active agents were imipenem, meropenem, and fosfomycin (100%), followed by amikacin (99.1%) and nitrofurantoin (84%). The least active substances were ampicillin-clavulanate (20%), sulfamethoxazole (28%), and ciprofloxacin (29.6%). ESBL-EC isolates from urological and non-urological patients showed similar susceptibility profiles. However, ESBL-EC isolates from urological patients were significantly less susceptible to ciprofloxacin compared to non-urological isolates (14.7 vs. 32.7%, p < 0.05). CONCLUSIONS: The rate of urinary ESBL-EC isolates is increasing. Their susceptibility to nitrofurantoin, fosfomycin, and carbapenems is excellent, whereas ampicillin-clavulanate, sulfamethoxazole, and ciprofloxacin demonstrate only low susceptibility. In particular, the use of ciprofloxacin should be strictly avoided in urologic patients with suspicion for an ESBL-EC urinary tract infection as well as routine antibiotic prophylaxis prior to urological interventions if not explicit indicated by current international guidelines or local resistance patterns.


Asunto(s)
Ciprofloxacina/uso terapéutico , Farmacorresistencia Bacteriana , Infecciones por Escherichia coli/epidemiología , Escherichia coli/aislamiento & purificación , Infecciones Urinarias/epidemiología , Sistema Urinario/microbiología , beta-Lactamasas/metabolismo , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Antibacterianos/farmacología , Antibacterianos/uso terapéutico , Carbapenémicos/farmacología , Carbapenémicos/uso terapéutico , Ciprofloxacina/farmacología , Contraindicaciones , Escherichia coli/efectos de los fármacos , Escherichia coli/metabolismo , Infecciones por Escherichia coli/tratamiento farmacológico , Femenino , Fosfomicina/farmacología , Fosfomicina/uso terapéutico , Humanos , Masculino , Persona de Mediana Edad , Nitrofurantoína/farmacología , Nitrofurantoína/uso terapéutico , Prevalencia , Estudios Retrospectivos , Insuficiencia del Tratamiento , Resultado del Tratamiento , Infecciones Urinarias/tratamiento farmacológico , Infecciones Urinarias/microbiología , Adulto Joven
19.
World J Urol ; 31(3): 579-84, 2013 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-23053214

RESUMEN

BACKGROUND: Microbial ureteral stent colonisation (MUSC) is one leading risk factor for complications associated with ureteral stent placement. As MUSC remains frequently undetected by standard urine cultures, its definitive diagnosis depends on microbiological investigation of the stent. However, a standard reference laboratory technique for studying MUSC is still lacking. MATERIALS AND METHODS: A total of 271 ureteral stents removed from 199 consecutive patients were investigated. Urine samples were obtained prior to device removal. Stents were divided into four parts. Each part was separately processed by the microbiology laboratory within 6 h. Ureteral stents were randomly allocated to roll-plate or sonication, respectively, and analysed using standard microbiological techniques. Demographic and clinical data were prospectively collected using a standard case-report form. RESULTS: Overall, roll-plate showed a higher detection rate of MUSC compared with sonication (35 vs. 28 %, p < 0.05) and urine culture (35 vs. 8 %, p < 0.05). No inferiority of Maki's technique was observed even when stents were stratified according to indwelling time below or above 30 days. Compared with roll-plate, sonication commonly failed to detect Enterococcus spp., coagulase-negative staphylococci (CoNS) and Enterobacteriaceae. In addition, sonication required more hands-on time, more equipment and higher training than roll-plate in the laboratory. CONCLUSIONS: This prospective randomised study demonstrates the superiority of Maki's roll-plate technique over sonication in the diagnosis of MUSC and that urine culture is less sensitive than both methods. The higher detection rate, simplicity and cost-effectiveness render roll-plate the methodology of choice for routine clinical investigation as well as basic laboratory research.


Asunto(s)
Infecciones Relacionadas con Catéteres/diagnóstico , Infecciones por Enterobacteriaceae/diagnóstico , Enterobacteriaceae/aislamiento & purificación , Enterococcus/aislamiento & purificación , Técnicas Microbiológicas/métodos , Infecciones Estreptocócicas/diagnóstico , Catéteres Urinarios/microbiología , Adulto , Anciano , Infecciones Relacionadas con Catéteres/microbiología , Recuento de Colonia Microbiana , Análisis Costo-Beneficio , Infecciones por Enterobacteriaceae/microbiología , Femenino , Humanos , Masculino , Persona de Mediana Edad , Estudios Prospectivos , Sensibilidad y Especificidad , Sonicación/métodos , Infecciones Estreptocócicas/microbiología , Orina/microbiología
20.
J Appl Microbiol ; 115(5): 1186-93, 2013 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-23865534

RESUMEN

AIMS: Urinary tract infection (UTI) caused by Candida spp. is an increasing problem in clinical practice. Risk factors include diabetes mellitus, extremes of age, urinary tract abnormalities and indwelling catheters. Here, we determined the applicability of isothermal microcalorimetry (IMC) for the detection and antifungal drug susceptibility testing of Candida albicans in artificial urine. METHODS AND RESULTS: Isothermal microcalorimetry was used to monitor the metabolic heat production rates of C. albicans at 37 °C (µW = µJ s(-1) ). The influence of increasing concentrations of glucose and antifungal drugs on the growth of C. albicans was investigated. The growth rate increased linearly from 0.024 ± 0.010 to 0.203 ± 0.006 h(-1) with increasing concentration of glucose from 20 to 1640 mg l(-1) . The minimum inhibitory concentrations (MIC) against C. albicans were determined at a fixed glucose concentration of 560 mg l(-1) . These MIC were 0.5 µg ml(-1) for amphotericin B, 5 µg ml(-1) for flucytosine, 0.8 µg ml(-1) for fluconazole and 0.5 µg ml(-1) for tioconazole, respectively. CONCLUSIONS: IMC is able to detect and quantify growth of C. albicans in artificial urine and to determine the MIC of antifungal drugs against C. albicans. This study demonstrated that IMC can be used for basic research on Candida-UTI and opens promising avenue for the use of IMC as rapid drug resistance screening tool and diagnostic tool. SIGNIFICANCE AND IMPACT OF STUDY: Little is known on the growth of C. albicans in urine. Our study provides measurements of the growth rate of this yeast in urine with various glucose concentrations. Thus, important insights are gathered for risk group such as patients with diabetes or patients with prolonged parenteral nutrition resulting in higher urinary glucose concentration.


Asunto(s)
Antifúngicos/farmacología , Candida albicans/efectos de los fármacos , Glucosa/química , Orina/microbiología , Anfotericina B/farmacología , Calorimetría , Candida albicans/crecimiento & desarrollo , Fluconazol/farmacología , Flucitosina/farmacología , Humanos , Imidazoles/farmacología , Pruebas de Sensibilidad Microbiana , Infecciones Urinarias/tratamiento farmacológico , Infecciones Urinarias/microbiología
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