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1.
BMC Urol ; 23(1): 46, 2023 Mar 28.
Artigo em Inglês | MEDLINE | ID: mdl-36978025

RESUMO

BACKGROUND: We evaluated the hydrostatic pressure of the renal pelvis (RPP) as a radiation-free alternative to fluoroscopic nephrostogram to assess ureteral patency after percutaneous nephrolithotomy (PCNL). METHODS: Retrospective non-inferiority study analyzing 248 PCNL-patients (86 female (35%) and 162 males (65%)) between 2007 and 2015. Postoperatively, RPP was measured using a central venous pressure manometer in cmH2O. The primary endpoint was to assess RPP depending on the patency of the ureter and the nephrostomy tube removal. Secondary, the upper limit of normal RPP of [Formula: see text] 20 cmH2O was assessed as an indicator of an unobstructed patency. RESULTS: The median procedure duration was 141 min (112-171.5) with a stone free rate of 82% (n = 202). RPP was significantly higher in patients with obstructive nephrostogram with 25.0 mmH2O (21.0-32.0) versus 20.0 mmH2O (16.0-24.0; p < 0.001). The pressure was lower in successful nephrostomy removal with 18 cmH2O (15-21) versus 23 cmH2O (20-29) in the leakage group (p < 0.001). The analysis of a cut-off of [Formula: see text] 20 cmH2O showed a sensitivity of 76.9% (95% CI [60.7%; 88.9%]) and a specificity of 61.5% (95% CI [54.6%; 68.2%]). The negative predictive value was 93.4% (95% CI: [87.9%; 97.0%]) and the positive predictive value 27.3% (95% CI [19.2%; 36.6%]). The accuracy of the model showed an AUC = 0.795 (95% CI [0.668; 0.862]). CONCLUSION: The hydrostatic RPP seems to allow a bedside evaluation of ureteral patency after PCNL.


Assuntos
Cálculos Renais , Nefrolitotomia Percutânea , Nefrostomia Percutânea , Masculino , Humanos , Feminino , Nefrolitotomia Percutânea/métodos , Pressão Hidrostática , Cálculos Renais/diagnóstico por imagem , Cálculos Renais/cirurgia , Estudos Retrospectivos , Pelve Renal/diagnóstico por imagem , Pelve Renal/cirurgia , Nefrostomia Percutânea/métodos
2.
Small ; 18(9): e2105896, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-34913586

RESUMO

The poor chemical miscibility between metal and organic materials usually leads to both structural and energetic mismatches at gold/organic interfaces, and thereby, high contact resistance of organic electronic devices. This study shows that the contact resistance of organic field-effect transistors is significantly reduced by one order of magnitude, by reforming the contact interface between gold electrodes and conjugated polymers upon a polymer insulator-assisted thermal annealing. Upon an optimized solution process, the conjugated polymer is homogenously distributed within the amorphous polymer insulator matrix with relatively low glass transition temperature, and thus, even a moderate annealing temperature can induce sufficient motion of conjugated polymer chains to simultaneously adjust the polymer orientation and improve the packing of gold atoms. Consequently, gold/conjugated polymer contact is reorganized after annealing, which improves both charge transport from bulk gold to interface and charge injection from gold into conjugated polymers. This method, with appropriate insulator matrix, is effective for improving the injection of both holes and electrons, and widely applicable for many unipolar and ambipolar conjugated polymers to optimize the device performance and simultaneously increase the optical transparency (over 80%). A frequency doubler and a phase modulator are demonstrated, respectively, using the ambipolar transistors with optimized charge injection properties.

3.
Langmuir ; 38(39): 11983-11993, 2022 Oct 04.
Artigo em Inglês | MEDLINE | ID: mdl-36150131

RESUMO

Ultrasmall nanoparticles (NPs) with a high active surface area are essential for optoelectronic and photovoltaic applications. However, the structural stability and sustainability of these ultrasmall NPs at higher temperatures remain a critical problem. Here, we have synthesized the nanocomposites (NCs) of Ag NPs inside the silica matrix using the atom beam co-sputtering technique. The post-deposition growth of the embedded Ag NPs is systematically investigated at a wide range of annealing temperatures (ATs). A novel, fast, and effective procedure, correlating the experimental (UV-vis absorption results) and theoretical (quantum mechanical modeling, QMM) results, is used to estimate the size of NPs. The QMM-based simulation, employed for this work, is found to be more accurate in reproducing the absorption spectra over the classical/modified Drude model, which fails to predict the expected shift in the LSPR for ultrasmall NPs. Unlike the classical Drude model, the QMM incorporates the intraband transition of the conduction band electrons to calculate the effective dielectric function of metallic NCs, which is the major contribution of LSPR shifts for ultrasmall NPs. In this framework, a direct comparison is made between experimentally and theoretically observed LSPR peak positions, and it is observed that the size of NPs grows from 3 to 18 nm as AT increases from room temperature to 900 °C. Further, in situ grazing-incidence small- & wide-angle X-ray scattering and transmission electron microscopy measurements are employed to comprehend the growth of Ag NPs and validate the UV + QMM results. We demonstrate that, unlike chemically grown NPs, the embedded Ag NPs ensure greater stability in size and remain in an ultrasmall regime up to 800 °C, and beyond this temperature, the size of NPs increases exponentially due to dominant Ostwald ripening. Finally, a three-stage mechanism is discussed to understand the process of nucleation and growth of the silica-embedded Ag NPs.

4.
Urol Int ; 106(8): 775-783, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-34963122

RESUMO

INTRODUCTION: The aim of the study was to evaluate the effectiveness of a modified transvesical obturator nerve block (ONB) in the prevention of obturator nerve reflex and consecutive bladder perforations (BPs) during transurethral resection of bladder tumors (TURBTs). MATERIALS AND METHODS: A retrospective analysis of all patients resected in 2014-2015 due to a bladder tumor of the lateral walls, including a follow-up period until December 2018, was performed. Two groups were defined: in the first group, all patients underwent TURBT with a modified transvesical ONB. The second group underwent conventional TURBT with intermittent resection. Primary endpoints were the rates of adductor contractions and BPs. RESULTS: Ninety-four out of 1,145 resected patients presented with tumors on the lateral wall of the bladder and a complete dataset including a long-term follow-up. Thirty-six patients were treated in the ONB group, and 58 patients comprised the control group. The median age in the 2 groups was 70.8 and 71.8 years in the first and second groups, respectively. Adductor spasms were reported in 8.33 versus 25.86% (p = 0.057) and perforation in 2.78 versus 17.24% (p = 0.047) in groups 1 and 2, respectively. After a median follow-up of 32.5 months, there was no significant difference in recurrence rates (52.78 vs. 51.72%, p = 0.672). In a subgroup analysis, lower perforation rates were recorded for the ONB group in patients with tumors <3 cm (0/30 vs. 8/46, p = 0.076) and in patients with unifocal tumors (0/12 vs. 5/23, p = 0.141). DISCUSSION/CONCLUSION: The simplified approach of transvesical ONB demonstrated in this study appears to be an inexpensive, safe, effective, and simple-to-use technique.


Assuntos
Bloqueio Nervoso , Neoplasias da Bexiga Urinária , Idoso , Cistectomia/efeitos adversos , Cistectomia/métodos , Humanos , Bloqueio Nervoso/efeitos adversos , Bloqueio Nervoso/métodos , Nervo Obturador/patologia , Estudos Retrospectivos , Neoplasias da Bexiga Urinária/patologia , Neoplasias da Bexiga Urinária/cirurgia
5.
Biomacromolecules ; 22(10): 4274-4283, 2021 10 11.
Artigo em Inglês | MEDLINE | ID: mdl-34541856

RESUMO

The nano- to microscale structures at the interface between materials can define the macroscopic material properties. These structures are extremely difficult to investigate for complex material systems, such as cellulose-rich materials. The development of new model cellulose materials and measuring techniques has opened new possibilities to resolve this problem. We present a straightforward approach combining micro-focusing grazing-incidence small-angle X-ray scattering and atomic force microscopy (AFM) to investigate the structural rearrangements of cellulose/cellulose interfaces in situ during drying. Based on the results, we propose that molecular interdiffusion and structural rearrangement play a major role in the development of the properties of the cellulose/cellulose interphase; this model is representative of the development of the properties of joint/contact points between macroscopic cellulose fibers.


Assuntos
Celulose , Incidência , Interfase , Difração de Raios X , Raios X
6.
J Chem Phys ; 155(12): 124902, 2021 Sep 28.
Artigo em Inglês | MEDLINE | ID: mdl-34598569

RESUMO

We examine network formation and percolation of carbon black by means of Monte Carlo simulations and experiments. In the simulation, we model carbon black by rigid aggregates of impenetrable spheres, which we obtain by diffusion-limited aggregation. To determine the input parameters for the simulation, we experimentally characterize the micro-structure and size distribution of carbon black aggregates. We then simulate suspensions of aggregates and determine the percolation threshold as a function of the aggregate size distribution. We observe a quasi-universal relation between the percolation threshold and a weighted average radius of gyration of the aggregate ensemble. Higher order moments of the size distribution do not have an effect on the percolation threshold. We conclude further that the concentration of large carbon black aggregates has a stronger influence on the percolation threshold than the concentration of small aggregates. In the experiment, we disperse the carbon black in a polymer matrix and measure the conductivity of the composite. We successfully test the hypotheses drawn from simulation by comparing composites prepared with the same type of carbon black before and after ball milling, i.e., on changing only the distribution of aggregate sizes in the composites.

7.
Strahlenther Onkol ; 196(4): 386-397, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-31919547

RESUMO

BACKGROUND: Preoperative radiotherapy (PRT) or radiochemotherapy (PRCT) is used in different tumor sites. The aim of the study was to examine the long-term quality of life (QoL) of localized / locally advanced breast cancer patients treated with PRT/PRCT followed by breast-conserving surgery (BCS) or mastectomy (ME). METHODS: Assessment of QoL was done using EORTC QLQ-C30 questionnaires for overall QoL and EORTC QLQ-BR23 for breast-specific QoL. The summary scores were categorized into 4 distinct groups to classify the results. Furthermore, a comparative analysis was performed between the study cohort and a previously published reference cohort of healthy adults. We assessed the impact of different clinical, prognostic, and treatment-related factors on selected items from C30 and BR23 using a dependence analysis. RESULTS: Out of 315 patients treated with PRT/PCRT in the years 1991 to 1999, 203 patients were alive at long-term follow-up after a mean of 17.7 years (range 14-21). 37 patients were lost to follow-up and 61 patients refused to be contacted, leading to 105 patients (64 patients after BCS and 41 after ME) being willing to undergo further clinical assessment regarding QoL outcome. Overall, QoL (QLQ-C30) was rated "excellent" or "good" in 85% (mean value) of all patients (BCS 83%, ME 88%). Comparative analysis between the study cohort and a published healthy control group revealed significantly better global health status and physical and role functioning scores in the PRT/PRCT group. The analysis demonstrates no differences in nausea/vomiting, dyspnea, insomnia, constipation, or financial difficulties. According to the dependence analysis, global QoL was associated with age, operation type and ME reconstruction. CONCLUSION: We did not detect any inferiority of PRT/PRCT compared to a healthy reference group with no hints of a detrimental long-term effect on general and breast-specific quality of life.


Assuntos
Neoplasias da Mama/terapia , Quimiorradioterapia Adjuvante/efeitos adversos , Qualidade de Vida , Radioterapia de Intensidade Modulada/métodos , Neoplasias da Mama/patologia , Feminino , Humanos , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Cuidados Pré-Operatórios , Radiodermite/prevenção & controle , Radiometria , Planejamento da Radioterapia Assistida por Computador/métodos
8.
Soft Matter ; 16(23): 5439-5449, 2020 Jun 17.
Artigo em Inglês | MEDLINE | ID: mdl-32469347

RESUMO

Hydrodynamic alignment of proteinaceous or polymeric nanofibrillar building blocks can be utilized for subsequent assembly into intricate three-dimensional macrostructures. The non-equilibrium structure of flowing nanofibrils relies on a complex balance between the imposed flow-field, colloidal interactions and Brownian motion. The understanding of the impact of non-equilibrium dynamics is not only weak, but is also required for structural control. Investigation of underlying dynamics imposed by the flow requires in situ dynamic characterization and is limited by the time-resolution of existing characterization methods, specifically on the nanoscale. Here, we present and demonstrate a flow-stop technique, using polarized optical microscopy (POM) to quantify the anisotropic orientation and diffusivity of nanofibrils in shear and extensional flows. Microscopy results are combined with small-angle X-ray scattering (SAXS) measurements to estimate the orientation of nanofibrils in motion and simultaneous structural changes in a loose network. Diffusivity of polydisperse systems is observed to act on multiple timescales, which is interpreted as an effect of apparent fibril lengths that also include nanoscale entanglements. The origin of the fastest diffusivity is correlated to the strength of velocity gradients, independent of type of deformation (shear or extension). Fibrils in extensional flow results in highly anisotropic systems enhancing interfibrillar contacts, which is evident through a slowing down of diffusive timescales. Our results strongly emphasize the need for careful design of fluidic microsystems for assembling fibrillar building blocks into high-performance macrostructures relying on improved understanding of nanoscale physics.

9.
Phys Chem Chem Phys ; 22(5): 3097-3104, 2020 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-31967129

RESUMO

Small π-conjugated organic molecules have attracted substantial attention in the past decade as they are considered as candidates for future organic-based (opto-)electronic applications. The molecular arrangement in the organic layer is one of the crucial parameters that determine the efficiency of a given device. The desired orientation of the molecules is achieved by a proper choice of the underlying substrate and growth conditions. Typically, one underlying material supports only one inherent molecular orientation at its interface. Here, we report on two different orientations of diindenoperylene (DIP) molecules on the same underlayer, i.e. on a few-layer MoS2 substrate. We show that DIP molecules adopt a lying-down orientation when deposited on few-layer MoS2 with horizontally oriented layers. In contrast, for vertically aligned MoS2 layers, DIP molecules are arranged in a standing-up manner. Employing in situ and real-time grazing-incidence wide-angle X-ray scattering (GIWAXS), we monitored the stress evolution within the thin DIP layer from the early stages of the growth, revealing different substrate-induced phases for the two molecular orientations. Our study opens up new possibilities for the next-generation of flexible electronics, which might benefit from the combination of MoS2 layers with unique optical and electronic properties and an extensive reservoir of small organic molecules.

10.
Proc Natl Acad Sci U S A ; 114(6): 1232-1237, 2017 02 07.
Artigo em Inglês | MEDLINE | ID: mdl-28123065

RESUMO

Some of the most remarkable materials in nature are made from proteins. The properties of these materials are closely connected to the hierarchical assembly of the protein building blocks. In this perspective, amyloid-like protein nanofibrils (PNFs) have emerged as a promising foundation for the synthesis of novel bio-based materials for a variety of applications. Whereas recent advances have revealed the molecular structure of PNFs, the mechanisms associated with fibril-fibril interactions and their assembly into macroscale structures remain largely unexplored. Here, we show that whey PNFs can be assembled into microfibers using a flow-focusing approach and without the addition of plasticizers or cross-linkers. Microfocus small-angle X-ray scattering allows us to monitor the fibril orientation in the microchannel and compare the assembly processes of PNFs of distinct morphologies. We find that the strongest fiber is obtained with a sufficient balance between ordered nanostructure and fibril entanglement. The results provide insights in the behavior of protein nanostructures under laminar flow conditions and their assembly mechanism into hierarchical macroscopic structures.


Assuntos
Lactoglobulinas/química , Nanoestruturas/química , Microscopia de Força Atômica , Reologia , Espalhamento a Baixo Ângulo
11.
J Am Chem Soc ; 141(50): 19700-19707, 2019 Dec 18.
Artigo em Inglês | MEDLINE | ID: mdl-31747277

RESUMO

Perovskite solar cells (PSCs) has skyrocketed in the past decade to an unprecedented level due to their outstanding photoelectric properties and facile processability. However, the utilization of expensive hole transport materials (HTMs) and the inevitable instability instigated by the deliquescent dopants represent major concerns hindering further commercialization. Here, a series of low-cost, conjugated polymers are designed and applied as dopant-free HTMs in PSCs, featuring tuned energy levels, good temperature and humidity resistivity, and excellent photoelectric properties. Further studies highlight the critical and multifaceted roles of the polymers with respect to facilitating charge separation, passivating the surface trap sites of perovskite materials, and guaranteeing long-term stability of the devices. A stabilized power conversion efficiency (PCE) of 20.3% and remarkably enhanced device longevity are achieved using the dopant-free polymer P3 with a low concentration of 5 mg/mL, qualifying the device as one of the best PSC systems constructed on the basis of dopant-free HTMs so far. In addition, the flexible PSCs based on P3 also exhibit a PCE of 16.2%. This work demonstrates a promising route toward commercially viable, stable, and efficient PSCs.

12.
Strahlenther Onkol ; 195(7): 615-628, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31101954

RESUMO

BACKGROUND: Preoperative radiotherapy and chemoradiotherapy (PRT/PCRT) represent an increasingly used clinical strategy in different tumor sites. We have previously reported on a PRT/PRCT protocol in patients with locally advanced non-inflammatory breast cancer (LABC) with promising clinical results. However, concerns regarding a possible unfavorable influence on cosmesis still exist. Thus, the aim of the current study was to examine long-term cosmetic outcome in our series of LABC patients treated with PRT/PCRT followed by breast-conserving surgery (BCS) or mastectomy (ME). PATIENTS AND METHODS: Of the 315 patients treated with PRT/PCRT in the years 1991 to 1999, 203 were still alive at long-term follow-up of mean 17.7 years (range 14-21). Thirty-seven patients were lost to follow-up and 58 patients refused to be contacted, which resulted in 107 patients (64 patients after BCS and 43 after mastectomy) being available and willing to undergo further cosmetic assessment. One patient had a complete response after PRT/PCRT and refused surgery. PRT/PCRT consisted of external beam radiation therapy (EBRT) with 50 Gy (5â€¯× 2 Gy/week) to the breast and the supra-/infraclavicular lymph nodes combined with a consecutive electron boost or (in case of BCS) a 10-Gy interstitial brachytherapy boost with Ir-192 prior to EBRT. Overall, chemotherapy was administered either prior to RT or concomitantly in the majority of patients. BCS and mastectomy were performed with and without reconstruction. The cosmetic outcome was assessed by patient questionnaire, panel evaluation, and breast retraction assessment (BRA) score. RESULTS: Eighty percent of all BCS patients rated their overall cosmetic result as "excellent" or "good" as compared to 55.8% after mastectomy. Patient and panel ratings on cosmetic outcomes were similar between the two groups. No grade III or IV fibrosis were detected in any of the groups. The median BRA score after breast conserving surgery was 2.9. CONCLUSION: PRT/PCRT is associated with low grades of fibrosis and a good to excellent long-term cosmetic outcome.


Assuntos
Neoplasias da Mama/terapia , Quimiorradioterapia , Estética , Mastectomia Segmentar , Mastectomia , Terapia Neoadjuvante , Complicações Pós-Operatórias/etiologia , Adulto , Neoplasias da Mama/patologia , Terapia Combinada , Feminino , Seguimentos , Humanos , Irradiação Linfática , Mamoplastia , Pessoa de Meia-Idade , Satisfação do Paciente , Complicações Pós-Operatórias/prevenção & controle , Inquéritos e Questionários
13.
Angew Chem Int Ed Engl ; 58(51): 18562-18569, 2019 12 16.
Artigo em Inglês | MEDLINE | ID: mdl-31600016

RESUMO

Designing engineering materials with high stiffness and high toughness is challenging as stiff materials tend to be brittle. Many biological materials realize this objective through multiscale (i.e., atomic- to macroscale) mechanisms that are extremely difficult to replicate in synthetic materials. Inspired from the architecture of such biological structures, we here present flow-assisted organization and assembly of renewable native cellulose nanofibrils (CNFs), which yields highly anisotropic biofibers characterized by a unique combination of high strength (1010 MPa), high toughness (62 MJ m-3 ) and high stiffness (57 GPa). We observed that properties of the fibers are primarily governed by specific ion characteristics such as hydration enthalpy and polarizability. A fundamental facet of this study is thus to elucidate the role of specific anion binding following the Hofmeister series on the mechanical properties of wet fibrillar networks, and link this to the differences in properties of dry nanostructured fibers. This knowledge is useful for rational design of nanomaterials and is critical for validation of specific ion effect theories. The bioinspired assembly demonstrated here is relevant example for designing high-performance materials with absolute structural control.


Assuntos
Íons/química , Nanofibras/química , Humanos
14.
Opt Express ; 26(8): 10968-10980, 2018 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-29716025

RESUMO

Laser drop on demand jetting of Cu-base braze droplets was proven a suitable method for joining wires to electrode structures of electronic devices, particularly if the electrical contacts need to withstand high thermal loads. During joining, a braze preform of 600 µm diameter is placed inside a capillary, molten by a laser pulse and subsequently ejected from the capillary by inert gas overpressure similarly to conventional solder ball bumping processes. However, since the liquidus temperature of the used braze material of 990 °C is about 760 °C higher than of standard Sn-based solders used in electronics packaging, the system technology was modified significantly to enable jetting of CuSn alloys. In particular, the beam source emits a five times higher optical output power than standard machines designed for processing Sn-based solders. In addition, a modified capillary made from technical ceramic was machined, to withstand the significantly higher heating- and cooling rates during the process. In order to understand the influence of capillary geometry on droplet detachment, and flight trajectory, two capillary geometries were machined applying a picosecond laser ablation process. Subsequently, stereoscopic high speed videos of droplet detachment and flight phase were analyzed. Using this approach it is possible, to determine droplet flight trajectories, velocities and lateral positional deviations in dependency of relative inert gas overpressure inside the machining head, pulse power and capillary geometry. The findings indicate a significant influence of the capillary geometry and the applied overpressure on the droplet flight trajectory, whereas the role of the laser pulse power seems neglectable.

15.
Soft Matter ; 14(31): 6582-6594, 2018 Aug 21.
Artigo em Inglês | MEDLINE | ID: mdl-30052259

RESUMO

The effect of chain architecture on the swelling and thermal response of thin films obtained from an amphiphilic three-arm star-shaped thermo-responsive block copolymer poly(methoxy diethylene glycol acrylate)-block-polystyrene ((PMDEGA-b-PS)3) is investigated by in situ neutron reflectivity (NR) measurements. The PMDEGA and PS blocks are micro-phase separated with randomly distributed PS nanodomains. The (PMDEGA-b-PS)3 films show a transition temperature (TT) at 33 °C in white light interferometry. The swelling capability of the (PMDEGA-b-PS)3 films in a D2O vapor atmosphere is better than that of films from linear PS-b-PMDEGA-b-PS triblock copolymers, which can be attributed to the hydrophilic end groups and limited size of the PS blocks in (PMDEGA-b-PS)3. However, the swelling kinetics of the as-prepared (PMDEGA-b-PS)3 films and the response of the swollen film to a temperature change above the TT are significantly slower than that in the PS-b-PMDEGA-b-PS films, which may be related to the conformation restriction by the star-shape. Unlike in the PS-b-PMDEGA-b-PS films, the amount of residual D2O in the collapsed (PMDEGA-b-PS)3 films depends on the final temperature. It decreases from (9.7 ± 0.3)% to (7.0 ± 0.3)% or (6.0 ± 0.3)% when the final temperatures are set to 35 °C, 45 °C and 50 °C, respectively. This temperature-dependent reduction of embedded D2O originates from the hindrance of chain conformation from the star-shaped chain architecture.

16.
BMC Urol ; 17(1): 3, 2017 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-28056942

RESUMO

BACKGROUND: Stone retropulsion represents a challenge for intracorporeal lithotripsy of ureteral calculi. The consequences are an increased duration and cost of surgery as well as decreased stone-free rates. The use of additional tools to prevent proximal stone migration entails further costs and risks for ureteral injuries. We present the simple technique of using a coil of the routinely used guidewire to prevent stone retropulsion. METHODS: We retrospectively evaluated all patients with mid-to-proximal ureteral stones in 2014, which were treated by ureteroscopic lithotripsy (Ho: YAG and/or pneumatic lithotripsy). The preoperative stone burden was routinely assessed using low dose CT scan (if available) and/or intravenous pyelogram. RESULTS: The study population consisted of 55 patients with 61 mid-to-proximal calculi. Twentyseven patients underwent semirigid ureterorenoscopy using the "Guidewire-Coil-Technique", the second group (n = 28) served as control group using the guidewire as usual. There has been a statistically significant reduction of accidental stone retropulsion (2/27 vs. 8/28, p < 0.05) as well as a decreased use of auxiliary procedures (p < 0.05) compared to the control group. No difference was observed in operative time. One ureteral injury in the control group required a prolonged ureteral stenting. CONCLUSION: The "Guidewire-Coil-Technique" is a simple and safe procedure that may help to prevent proximal calculus migration and therefore may increase stone-free rates without causing additional costs.


Assuntos
Cuidados Intraoperatórios/instrumentação , Complicações Intraoperatórias/prevenção & controle , Litotripsia , Cálculos Ureterais/cirurgia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos
17.
Urol Int ; 98(4): 478-482, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-27806367

RESUMO

INTRODUCTION: We performed a professional campaign in Germany intending to establish the urologic profession as a competent and helpful point of contact for patients with cryptorchidism. The aim of this study was to assess the feasibility of this campaign and to quantify the efficacy of using Internet vs. social media. MATERIALS AND METHODS: The strategic design of the campaign comprised a strategy meeting, creation of a landing page, and targeted advertisements on Google in the form of Adwords and on Facebook in the form of sidebar ads and sponsored posts. Outcome measurements were number of impressions, homepage sessions, and downloads of an information brochure. RESULTS: The campaign generated 2,511,923 impressions, 7,369 homepage sessions and 1,086 downloads of information brochures using a total investment budget of 7,500€. Use of Google Adwords was more efficient on outcome measurements than Facebook. A subanalysis of Facebook advertisements showed that sidebar ads and sponsored posts were equally efficient. CONCLUSIONS: New media are an effective platform for a profession campaign. Google Adwords is a more effective and cost-efficient platform than Facebook for a targeted campaign.


Assuntos
Criptorquidismo/diagnóstico , Criptorquidismo/terapia , Internet , Educação de Pacientes como Assunto/métodos , Mídias Sociais , Urologia , Publicidade , Criança , Estudos de Viabilidade , Alemanha , Humanos , Masculino , Educação de Pacientes como Assunto/economia , Guias de Prática Clínica como Assunto , Sociedades Médicas
18.
J Urol ; 195(6): 1911-9, 2016 06.
Artigo em Inglês | MEDLINE | ID: mdl-26802582

RESUMO

PURPOSE: We used targeted mass spectrometry to study the metabolic fingerprint of urothelial cancer and determine whether the biochemical pathway analysis gene signature would have a predictive value in independent cohorts of patients with bladder cancer. MATERIALS AND METHODS: Pathologically evaluated, bladder derived tissues, including benign adjacent tissue from 14 patients and bladder cancer from 46, were analyzed by liquid chromatography based targeted mass spectrometry. Differential metabolites associated with tumor samples in comparison to benign tissue were identified by adjusting the p values for multiple testing at a false discovery rate threshold of 15%. Enrichment of pathways and processes associated with the metabolic signature were determined using the GO (Gene Ontology) Database and MSigDB (Molecular Signature Database). Integration of metabolite alterations with transcriptome data from TCGA (The Cancer Genome Atlas) was done to identify the molecular signature of 30 metabolic genes. Available outcome data from TCGA portal were used to determine the association with survival. RESULTS: We identified 145 metabolites, of which analysis revealed 31 differential metabolites when comparing benign and tumor tissue samples. Using the KEGG (Kyoto Encyclopedia of Genes and Genomes) Database we identified a total of 174 genes that correlated with the altered metabolic pathways involved. By integrating these genes with the transcriptomic data from the corresponding TCGA data set we identified a metabolic signature consisting of 30 genes. The signature was significant in its prediction of survival in 95 patients with a low signature score vs 282 with a high signature score (p = 0.0458). CONCLUSIONS: Targeted mass spectrometry of bladder cancer is highly sensitive for detecting metabolic alterations. Applying transcriptome data allows for integration into larger data sets and identification of relevant metabolic pathways in bladder cancer progression.


Assuntos
Biomarcadores Tumorais/metabolismo , Carcinoma de Células de Transição/metabolismo , Metaboloma , Neoplasias da Bexiga Urinária/metabolismo , Biomarcadores Tumorais/genética , Carcinoma de Células de Transição/genética , Carcinoma de Células de Transição/mortalidade , Estudos de Casos e Controles , Cromatografia Líquida , Humanos , Espectrometria de Massas , Metabolômica , Prognóstico , Transcriptoma , Neoplasias da Bexiga Urinária/genética , Neoplasias da Bexiga Urinária/mortalidade
19.
Opt Express ; 24(24): 27280-27287, 2016 Nov 28.
Artigo em Inglês | MEDLINE | ID: mdl-27906300

RESUMO

The optical transfer function (OTF) is widely used to compare the performance of different optical systems. Conventionally, the OTF is normalized to unity for zero spatial frequency, but in some cases it is better to consider the unnormalized OTF, which gives the absolute value of the image signal. Examples are in confocal microscopy and image scanning microscopy, where the signal level increases with pinhole or array size. Comparison of the respective unnormalized OTFs gives useful insight into their relative performance. The significance of other properties of the general OTF is discussed.

20.
Opt Lett ; 41(9): 2109-12, 2016 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-27128086

RESUMO

Concentration of light is limited by a fundamental physical principle, which ensures that étendue, the product of area and solid angle, can never decrease in an optical system. In microscopy, many superresolving methods, which can overcome the classical resolution limit, have recently emerged. We propose, and demonstrate experimentally, that it is also possible to circumvent the classical light concentration limit. Actually, most superresolution methods exhibit a common drawback: with respect to the total number of emitted photons, they are less efficient than standard widefield microscopy. Most methods "shave"' the point spread function (PSF) by discarding the disturbing signal from its edge. We show, that in contrast to PSF-shaving, methods related to reassignment microscopy (image scanning microscopy, optical photon reassignment, rescan confocal, instant structured illumination microscopy) concentrate all detected photons in their superresolving images and thereby increase the detected signal per sample area compared to widefield microsopy. We term this behavior superconcentration, as it breaks the classical light concentration limit.

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