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1.
J Eur Acad Dermatol Venereol ; 36(12): 2516-2524, 2022 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-35876737

RESUMEN

BACKGROUND: Artificial intelligence (AI) techniques are promising in early diagnosis of skin diseases. However, a precondition for their success is the access to large-scaled annotated data. Until now, obtaining this data has only been feasible with very high personnel and financial resources. OBJECTIVES: The aim of this study was to overcome the obstacle caused by the scarcity of labelled data. METHODS: To simulate the scenario of label shortage, we discarded a proportion of labels of the training set. The training set consisted of both labelled and unlabelled images. We then leveraged a self-supervised learning technique to pretrain the AI model on the unlabelled images. Next, we fine-tuned the pretrained model on the labelled images. RESULTS: When the images in the training dataset were fully labelled, the self-supervised pretrained model achieved 95.7% of accuracy, 91.7% of precision and 90.7% of sensitivity. When only 10% of the data were labelled, the model could still yield 87.7% of accuracy, 81.7% of precision and 68.6% of sensitivity. In addition, we also empirically verified that the AI model and dermatologists are consistent in visually inspecting the skin images. CONCLUSIONS: The experimental results demonstrate the great potential of the self-supervised learning in alleviating the scarcity of annotated data.


Asunto(s)
Inteligencia Artificial , Aprendizaje Profundo , Humanos , Piel
2.
Ann Oncol ; 29(10): 2105-2114, 2018 10 01.
Artículo en Inglés | MEDLINE | ID: mdl-30412221

RESUMEN

Background: The German multicenter randomized phase II larynx organ preservation (LOP) trial DeLOS-II was carried out to prove the hypothesis that cetuximab (E) added to induction chemotherapy (IC) and radiotherapy improves laryngectomy-free survival (LFS; survival with preserved larynx) in locally advanced laryngeal/hypopharyngeal cancer (LHSCC). Patients and methods: Treatment-naïve patients with stage III/IV LHSCC amenable to total laryngectomy (TL) were randomized to three cycles IC with TPF [docetaxel (T) and cisplatin (P) 75 mg/m2/day 1, 5-FU (F) 750 mg/m2/day days 1-5] followed by radiotherapy (69.6 Gy) without (A) or with (B) standard dose cetuximab for 16 weeks throughout IC and radiotherapy (TPFE). Response to first IC-cycle (IC-1) with ≥30% endoscopically estimated tumor surface shrinkage (ETSS) was used to define early responders; early salvage TL was recommended to non-responders. The primary objective was 24 months LFS above 35% in arm B. Results: Of 180 patients randomized (July 2007 to September 2012), 173 fulfilled eligibility criteria (A/B: larynx 44/42, hypopharynx 41/46). Because of 4 therapy-related deaths among the first 64 randomized patients, 5-FU was omitted from IC in the subsequent 112 patients reducing further fatal toxicities. Thus, IC was TPF in 61 patients and TP in 112 patients, respectively. The primary objective (24 months LFS above 35%) was equally met by arms A (40/85, 47.1%) as well as B (41/88, 46.6%). One hundred and twenty-three early responders completed IC+RT; their overall response rates (TPF/TP) were 94.7%/87.2% in A versus 80%/86.0% in B. The 24 months overall survival (OS) rates were 68.2% and 69.3%. Conclusions: Despite being accompanied by an elevated frequency in adverse events, the IC with TPF/TP plus cetuximab was feasible but showed no superiority to IC with TPF/TP regarding LFS and OS at 24 months. Both early response and 24 months LFS compare very well to previous LOP trials and recommend effective treatment selection and stratification by ETSS. Clinical trial information: NCT00508664.


Asunto(s)
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Quimioradioterapia/mortalidad , Neoplasias Hipofaríngeas/terapia , Neoplasias Laríngeas/terapia , Laringectomía/mortalidad , Radioterapia/mortalidad , Terapia Recuperativa , Adulto , Anciano , Cetuximab/administración & dosificación , Cisplatino/administración & dosificación , Terapia Combinada , Docetaxel/administración & dosificación , Femenino , Fluorouracilo/administración & dosificación , Estudios de Seguimiento , Humanos , Neoplasias Hipofaríngeas/patología , Quimioterapia de Inducción , Neoplasias Laríngeas/patología , Masculino , Persona de Mediana Edad , Tratamientos Conservadores del Órgano , Pronóstico , Tasa de Supervivencia
3.
Prog Urol ; 28(5): 251-281, 2018 Apr.
Artículo en Francés | MEDLINE | ID: mdl-29428190

RESUMEN

This article aimed to gather male genital dermatoses that may lead to consult a urologist, except pre-neoplastic or neoplastic lesion. METHOD: This review is based on a research on Pubmed and EM-consult database, in English and in French, using the following key terms "male genital dermatoses", "male genital lesions", "balanitis", "balanoposthitis", "dermatoses des organes génitaux externes masculines", "lésions des organes génitaux externes de l'homme", "balanoposthites". RESULTS: It highlights normal morphological aspects, acute balanoposthitis (nonspecific, infectious, allergic, irritative and traumatic), common skin disease localized to male genital and male genital specific dermatoses. CONCLUSION: Any suspicious, fixed, must lead to a skin biopsy.


Asunto(s)
Balanitis/diagnóstico , Dermatología , Enfermedades de la Piel/diagnóstico , Urología , Balanitis/etiología , Balanitis/terapia , Medicina Basada en la Evidencia , Enfermedades de los Genitales Masculinos/diagnóstico , Humanos , Masculino , Enfermedades de la Piel/etiología , Enfermedades de la Piel/terapia , Enfermedades Cutáneas Parasitarias/diagnóstico , Enfermedades Cutáneas Virales/diagnóstico , Recursos Humanos
5.
Skin Res Technol ; 23(4): 602-606, 2017 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-28513053

RESUMEN

BACKGROUND: Acute radiation dermatitis (ARD) is a frequent complication after breast cancer radiotherapy and is usually assessed by semi-quantitative clinical scores, which may be subject to inter-observer variability. High-frequency ultrasound imaging of the skin can reliably quantify thickness and edema in diseased skin. We aimed to compare the relative increase in dermal thickness of the irradiated zone in breast-cancer patients undergoing radiotherapy, with clinical severity. METHODS: A consecutive series of patients undergoing treatment for breast cancer by lumpectomy and radiotherapy in a 6-month period also underwent clinical and ultrasound evaluation of ARD. RESULTS: We included 34 female patients 17 had grade 1 (group 1), 17 had grade 2 or grade 3 ARD (group 2). The mean relative increase in dermal thickness in irradiated skin (RIDTIS) was greater for group 2 than 1: 0.53 vs 0.29 mm (P=.023). On univariate analysis, ARD was associated with skin phototype, breast volume and RIDTIS, and on multivariable analysis, breast volume and age remained predictive of the disease. CONCLUSION: Patients with more severe dermatitis showed significantly increased dermal thickness. Dermal thickness is a quantitative variable that could help quantify the efficacy of drugs and improve the treatment of this disease in patients undergoing radiotherapy.


Asunto(s)
Neoplasias de la Mama/radioterapia , Radiodermatitis/diagnóstico por imagen , Enfermedad Aguda , Anciano , Femenino , Humanos , Persona de Mediana Edad , Proyectos Piloto , Curva ROC , Radiodermatitis/etiología , Ultrasonografía
6.
J Appl Microbiol ; 121(2): 587-97, 2016 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-27207818

RESUMEN

AIMS: To investigate the UVB-independent and exogenous indirect photoinactivation of eight human health-relevant bacterial species in the presence of photosensitizers. METHODS AND RESULTS: Eight bacterial species were exposed to simulated sunlight with greatly reduced UVB light intensity in the presence of three synthetic photosensitizers and two natural photosensitizers. Inactivation curves were fit with shoulder log-linear or first-order kinetic models, from which the presence of a shoulder and magnitude of inactivation rate constants were compared. Eighty-four percent reduction in the UVB light intensity roughly matched a 72-95% reduction in the overall bacterial photoinactivation rate constants in sensitizer-free water. With the UVB light mostly reduced, the exogenous indirect mechanism contribution was evident for most bacteria and photosensitizers tested, although most prominently with the Gram-positive bacteria. CONCLUSIONS: Results confirm the importance of UVB light in bacterial photoinactivation and, with the reduction of the UVB light intensity, that the Gram-positive bacteria are more vulnerable to the exogenous indirect mechanism than Gram-negative bacteria. SIGNIFICANCE AND IMPACT OF THE STUDY: UVB is the most important range of the sunlight spectrum for bacterial photoinactivation. In aquatic environments where photosensitizers are present and there is high UVB light attenuation, UVA and visible wavelengths can contribute to exogenous indirect photoinactivation.


Asunto(s)
Bacterias/crecimiento & desarrollo , Bacterias/efectos de la radiación , Viabilidad Microbiana/efectos de la radiación , Fármacos Fotosensibilizantes/farmacología , Bacterias/química , Bacterias/efectos de los fármacos , Humanos , Cinética , Fármacos Fotosensibilizantes/síntesis química , Luz Solar , Microbiología del Agua
7.
Laryngorhinootologie ; 95(2): 118-24, 2016 Feb.
Artículo en Alemán | MEDLINE | ID: mdl-26190042

RESUMEN

INTRODUCTION: The follow-up for head and neck cancer (HNC) focussed on therapy control. Accessory long term functionality is important. Impairment of function is observed, but a comparable documentation is not established. Additional we frequently see psychooncological comorbidities, what complicates the assessment. This was the reason why Tschiesner et al. developed on the base of the "ICF Core set for head and neck cancer" a guideline for the Assessment of Function in HNC. In consequence of good results in other tumour entities we developed an electronic version (OncoFunction). METHODS: In a proof of concept study all patients of our follow up consultation from 07/13 to 03/14 were included. OncoFunction was given to patients in a digital form using tablet computers. The results were visible to the physician in a concentrated form before consultation and were supplemented by a physician questionnaire. Furthermore we evaluated the usability in 202 patients. RESULTS: We had 682 patient contacts. 530 patient contacts (77, 7%) used the questionnaire. The physician questionnaire was answered in 470 times. Finally there are from 69.8% of the patient contacts full datasets available. Between users and non-users of the questionnaire we see no difference. CONCLUSION: The use of a computer-based screening and feedback system (OncoFunction) in clinical use is feasible and excellent assessed by patients. The patient data are visible in a compact form for the physician and problems can clear addressed to the patient. One more benefit is the standardized follow up documentation and the use of comparable data in research.


Asunto(s)
Cuidados Posteriores/organización & administración , Evaluación de la Discapacidad , Tamizaje Masivo/métodos , Sistemas de Registros Médicos Computarizados/organización & administración , Registros Médicos Orientados a Problemas , Neoplasias de Oído, Nariz y Garganta/terapia , Evaluación de Resultado en la Atención de Salud/organización & administración , Complicaciones Posoperatorias/diagnóstico , Programas Informáticos , Encuestas y Cuestionarios , Adulto , Anciano , Femenino , Guías como Asunto , Humanos , Masculino , Persona de Mediana Edad , Estadificación de Neoplasias , Neoplasias de Oído, Nariz y Garganta/patología , Satisfacción del Paciente , Calidad de Vida , Terminología como Asunto
8.
Ann Oncol ; 26(3): 561-7, 2015 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-25527417

RESUMEN

BACKGROUND: Squamous cell carcinoma of the head and neck (SCCHN) is a common disease, which has a poor prognosis after failure of therapy. Activation of the PI3K-AKT-mTOR axis is commonly detected in recurrent or metastatic SCCHN, and provided the rationale for the clinical phase II trial in pretreated SCCHN. PATIENTS AND METHODS: The primary end point was the progression-free survival rate (PFR) at 12 weeks. Forty eligible patients have been recruited after failure of platinum chemotherapy and cetuximab. A preplanned futility analysis was successfully passed after ≥1 success was detected in 20 patients. Secondary objectives consisted of progression-free survival (PFS), disease control rate (DCR), overall survival (OS), safety and tolerability, and predictive biomarkers for KRAS, BRAF, PIK3CA mutations, and HPV status. Archived tumor tissue was analyzed for DNA sequence. RESULTS: A total of 40 patients were eligible. The PFR at 12 weeks was 40% (95% CI 25.0-54.6). The median PFS and OS were 56 days (95% CI 36-113 days) and 152 days (76-256 days), respectively. In 33 assessable patients, disease stabilization occurred in 57.6%, with tumor shrinkage in 13 patients (39.4%). Overall, the treatment was well tolerated. Fatigue (47.5%), anemia (25.0%), nausea (20.0%), and pneumonia (20.0%) were the most common adverse events. Neither PIK3CA mutations, nor HPV status were predictive for success with temsirolimus treatment. No mutations were found for KRAS or BRAF. CONCLUSION: Tumor shrinkage and efficacy parameter indicate that inhibition of the PI3K-AKT-mTOR axis was a putative novel treatment paradigm for SCCHN. We could not identify parameters predictive for treatment success of temsirolimus, which underscores the need for refinement of the molecular analysis in future studies. CLINICAL TRIALS NUMBER: NCT01172769.


Asunto(s)
Protocolos de Quimioterapia Combinada Antineoplásica/administración & dosificación , Carcinoma de Células Escamosas/tratamiento farmacológico , Cetuximab/administración & dosificación , Cisplatino/administración & dosificación , Neoplasias de Cabeza y Cuello/tratamiento farmacológico , Recurrencia Local de Neoplasia/tratamiento farmacológico , Sirolimus/análogos & derivados , Adulto , Anciano , Carcinoma de Células Escamosas/diagnóstico , Carcinoma de Células Escamosas/epidemiología , Supervivencia sin Enfermedad , Femenino , Alemania/epidemiología , Neoplasias de Cabeza y Cuello/diagnóstico , Neoplasias de Cabeza y Cuello/epidemiología , Humanos , Masculino , Persona de Mediana Edad , Recurrencia Local de Neoplasia/diagnóstico , Sirolimus/administración & dosificación , Carcinoma de Células Escamosas de Cabeza y Cuello , Resultado del Tratamiento
9.
Environ Sci Technol ; 49(1): 423-31, 2015 Jan 06.
Artículo en Inglés | MEDLINE | ID: mdl-25489920

RESUMEN

Traditional beach management that uses concentrations of cultivatable fecal indicator bacteria (FIB) may lead to delayed notification of unsafe swimming conditions. Predictive, nowcast models of beach water quality may help reduce beach management errors and enhance protection of public health. This study compares performances of five different types of statistical, data-driven predictive models: multiple linear regression model, binary logistic regression model, partial least-squares regression model, artificial neural network, and classification tree, in predicting advisories due to FIB contamination at 25 beaches along the California coastline. Classification tree and the binary logistic regression model with threshold tuning are consistently the best performing model types for California beaches. Beaches with good performing models usually have a rainfall/flow related dominating factor affecting beach water quality, while beaches having a deteriorating water quality trend or low FIB exceedance rates are less likely to have a good performing model. This study identifies circumstances when predictive models are the most effective, and suggests that using predictive models for public notification of unsafe swimming conditions may improve public health protection at California beaches relative to current practices.


Asunto(s)
Playas , Modelos Estadísticos , Microbiología del Agua , Calidad del Agua , California , Enterobacteriaceae , Enterococcus , Ambiente , Heces/microbiología , Gastroenteritis , Humanos , Análisis de los Mínimos Cuadrados , Modelos Lineales , Modelos Logísticos , Modelos Teóricos , Redes Neurales de la Computación , Sensibilidad y Especificidad , Agua
10.
J Appl Microbiol ; 118(5): 1226-37, 2015 May.
Artículo en Inglés | MEDLINE | ID: mdl-25688992

RESUMEN

AIMS: To investigate how the growth stage of Enterococcus faecalis affects its photoinactivation in clear water. METHODS AND RESULTS: Enterococcus faecalis were grown in batch cultures to four different growth stages or grown in chemostats set at four different dilution rates, then harvested and exposed to full spectrum or UVB-blocked simulated sunlight. Experiments were conducted in triplicate in clear water with no added sensitizers. Decay curves were shoulder-log linear and were generally not statistically different in experiments conducted under full spectrum light. Shoulders were longer and first order inactivation rates smaller when experiments were seeded with cells grown to stationary as compared to exponential phase, and for slower growing cells when experiments were done under UVB-blocked light. Chemostat-sourced bacteria generally showed less variability among replicates than batch-sourced cells. CONCLUSIONS: The physiological state of cells and the method via which they are being generated may affect the photoinactivation experimental results. SIGNIFICANCE AND IMPACT OF THE STUDY: Photoinactivation experiments conducted with exponential phase cells may overestimate the photoinactivation kinetics in the environment, particular if UVB-independent mechanisms predominate. Chemostat-sourced cells are likely to provide more consistent experimental results than batch-sourced cells.


Asunto(s)
Enterococcus faecalis/crecimiento & desarrollo , Enterococcus faecalis/efectos de la radiación , Técnicas de Cultivo Celular por Lotes , Enterococcus faecalis/química , Cinética , Luz Solar
11.
Lett Appl Microbiol ; 61(2): 130-8, 2015 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-25900660

RESUMEN

UNLABELLED: Faecal indicator bacteria (FIB) and harmful algal blooms (HABs) threaten the health and the economy of coastal communities worldwide. Emerging automated sampling technologies combined with molecular analytical techniques could enable rapid detection of micro-organisms in-situ, thereby improving resource management and public health decision-making. We evaluated this concept using a robotic device, the Environmental Sample Processor (ESP). The ESP automates in-situ sample collection, nucleic acid extraction and molecular analyses. Here, the ESP measured and reported concentrations of FIB (Enterococcus spp.), a microbial source-tracking marker (human-specific Bacteriodales) and a HAB species (Psuedo-nitzschia spp.) over a 45-day deployment on the Santa Cruz Municipal Wharf (Santa Cruz, CA, USA). Both FIB and HABs were enumerated from single in-situ collected water samples. The in-situ qPCR efficiencies ranged from 86% to 105%, while the limit of quantifications during the deployment was 10 copies reaction(-1) . No differences were observed in the concentrations of enterococci, the human-specific marker in Bacteroidales spp., and P. australis between in-situ collected sample and traditional hand sampling methods (P > 0·05). Analytical results were Internet-accessible within hours of sample collection, demonstrating the feasibility of same-day public notification of current water quality conditions. SIGNIFICANCE AND IMPACT OF THE STUDY: This study presents the first report of in-situ qPCR enumeration of both faecal indicators and harmful algal species in coastal marine waters. We utilize a robotic device for in-situ quantification of enterococci, the human-specific marker in Bacteriodales and Pseudo-nitzschia spp. from the same water samples collected and processed in-situ. The results demonstrate that rapid, in-situ monitoring can be utilized to identify and quantify multiple health-relevant micro-organisms important in water quality monitoring and that this monitoring can be used to inform same-day notifications.


Asunto(s)
Enterococcus/aislamiento & purificación , Monitoreo del Ambiente/métodos , Heces/microbiología , Floraciones de Algas Nocivas , Reacción en Cadena en Tiempo Real de la Polimerasa/métodos , Enterococcus/genética , Humanos , Robótica , Calidad del Agua
12.
Eur Arch Otorhinolaryngol ; 272(8): 2017-25, 2015 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-24961436

RESUMEN

Based on level I evidence, postoperative platinum-based radiochemotherapy (PORCT) is the recommended standard of care in defined risk situations after resection of squamous cell carcinomas of the larynx and hypopharynx (LHSCC). The value of the addition of chemotherapy to adjuvant radiation in intermediate and high risk situations other than extracapsular spread or R1-/R2 resection is still debated. From 1993 to 2009, 555 patients (median follow-up: 24.4 months) with advanced LHSCC (UICC stages III-IVB) were treated in a curative intent. Patient data were continuously documented in the county of Leipzig cancer registry and were retrospectively analyzed as mono institutional survey. PORCT was introduced into the standard procedures in 2004, but also applied before in selected cases. Based on this paradigm shift, the patient population was divided into two comparative groups treated before and after 2004. 361 patients were treated before 2004. 43.8 % received primary surgery (OP) + postoperative radiotherapy (PORT) and 20.2 % OP + PORCT. 194 patients were treated after 2004: 21.1 % received OP + PORT and 35.6 % OP + PORCT. Regarding the PORCT groups, 20.6 % received cisplatin plus 5FU before 2004 which shifted to 59.4 % after 2004. The 3-year tumor-specific-survival rate of the whole cohort was improved from 47 to 60 % (p = 0.006). The subgroup treated with OP + PORT or PORCT improved from 56.1 to 68.5 % (p = 0.028). Localization proved to be a significant and independent factor. Only patients with advanced laryngeal cancer had significant improved survival (p < 0.01), while the improvement for hypopharyngeal cancer patients was not significant (p < 0.2). After 2004, there was a slight increase (+10.2 %) of primary radiochemotherapy (pRCT) due to stronger selection if R0 > 5 mm-resectability is unlikely. Standardised use of PORCT and pRCT considering clear indications showed to be significantly involved in improved survival in advanced LHSCC.


Asunto(s)
Carcinoma de Células Escamosas , Quimioterapia Adyuvante/métodos , Neoplasias de Cabeza y Cuello , Neoplasias Hipofaríngeas , Neoplasias Laríngeas , Radioterapia/métodos , Antineoplásicos/administración & dosificación , Carcinoma de Células Escamosas/patología , Carcinoma de Células Escamosas/terapia , Cisplatino/administración & dosificación , Terapia Combinada/métodos , Estudios de Seguimiento , Alemania , Neoplasias de Cabeza y Cuello/patología , Neoplasias de Cabeza y Cuello/terapia , Humanos , Neoplasias Hipofaríngeas/patología , Neoplasias Hipofaríngeas/terapia , Hipofaringe/patología , Hipofaringe/cirugía , Neoplasias Laríngeas/patología , Neoplasias Laríngeas/terapia , Laringe/patología , Laringe/cirugía , Masculino , Persona de Mediana Edad , Estadificación de Neoplasias , Evaluación de Resultado en la Atención de Salud , Estudios Retrospectivos , Carcinoma de Células Escamosas de Cabeza y Cuello , Tasa de Supervivencia
13.
Eur J Nucl Med Mol Imaging ; 41(4): 639-48, 2014 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-24292211

RESUMEN

PURPOSE: The aim of this study was to evaluate the diagnostic capability of simultaneous (18)F-fluorodeoxyglucose (FDG) positron emission tomography (PET)/MRI compared to (18)F-FDG PET/CT as well as their single components in head and neck cancer patients. METHODS: In a prospective study 17 patients underwent (18)F-FDG PET/CT for staging or follow-up and an additional (18)F-FDG PET/MRI scan with whole-body imaging and dedicated examination of the neck. MRI, CT and PET images as well as PET/MRI and PET/CT examinations were evaluated independently and in a blinded fashion by two reader groups. Results were compared with the reference standard (final diagnosis determined in consensus using all available data including histology and follow-up). Sensitivity, specificity, positive predictive value (PPV) and negative predictive value (NPV) were calculated. RESULTS: A total of 23 malignant tumours were found with the reference standard. PET/CT showed a sensitivity of 82.7%, a specificity of 87.3%, a PPV of 73.2% and a NPV of 92.4%. Corresponding values for PET/MRI were 80.5, 88.2, 75.6 and 92.5%. No statistically significant difference in diagnostic capability could be found between PET/CT and PET/MRI. Evaluation of the PET part from PET/CT revealed highest sensitivity of 95.7%, and MRI showed best specificity of 96.4%. There was a high inter-rater agreement in all modalities (Cohen's kappa 0.61-0.82). CONCLUSION: PET/MRI of patients with head and neck cancer yielded good diagnostic capability, similar to PET/CT. Further studies on larger cohorts to prove these first results seem justified.


Asunto(s)
Neoplasias de Cabeza y Cuello/diagnóstico por imagen , Imagen por Resonancia Magnética , Imagen Multimodal , Tomografía de Emisión de Positrones , Tomografía Computarizada por Rayos X , Adulto , Anciano , Femenino , Fluorodesoxiglucosa F18 , Neoplasias de Cabeza y Cuello/diagnóstico , Humanos , Masculino , Persona de Mediana Edad , Valor Predictivo de las Pruebas , Estudios Prospectivos , Radiofármacos
14.
J Opt Soc Am A Opt Image Sci Vis ; 31(4): A385-93, 2014 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-24695198

RESUMEN

Red, green, blue, yellow, and white have been distinguished from other hues as unique. We present results from two experiments that undermine existing behavioral evidence to separate the unique hues from other colors. In Experiment 1 we used hue scaling, which has often been used to support the existence of unique hues, but has never been attempted with a set of non-unique primaries. Subjects were assigned to one of two experimental conditions. In the "unique" condition, they rated the proportions of red, yellow, blue, and green that they perceived in each of a series of test stimuli. In the "intermediate" condition, they rated the proportions of teal, purple, orange, and lime. We found, surprisingly, that results from the two conditions were largely equivalent. In Experiment 2, we investigated the effect of instruction on subjects' settings of unique hues. We found that altering the color terms given in the instructions to include intermediate hues led to significant shifts in the hue that subjects identified as unique. The results of both experiments question subjects' abilities to identify certain hues as unique.


Asunto(s)
Percepción de Color , Artefactos , Color , Discriminación en Psicología/fisiología , Humanos , Estimulación Luminosa
15.
J Vis ; 14(13): 19, 2014 Nov 20.
Artículo en Inglés | MEDLINE | ID: mdl-25413625

RESUMEN

For anomalous trichromats, threshold contrasts for color differences captured by the L and M cones and their anomalous analogs are much higher than for normal trichromats. The greater spectral overlap of the cone sensitivities reduces chromatic contrast both at and above threshold. But above threshold, adaptively nonlinear processing might compensate for the chromatically impoverished photoreceptor inputs. Ratios of sensitivity for threshold variations and for color appearance along the two cardinal axes of MacLeod-Boynton chromaticity space were calculated for three groups: normals (N = 15), deuteranomals (N = 9), and protanomals (N = 5). Using a four-alternative forced choice (4AFC) task, threshold sensitivity was measured in four color-directions along the two cardinal axes. For the same participants, we reconstructed perceptual color spaces for the positions of 25 hues using multidimensional scaling (MDS). From the reconstructed color spaces we extracted "color difference ratios," defined as ratios for the size of perceived color differences along the L/(L + M) axis relative to those along the S/(L + M) axis, analogous to "sensitivity ratios" extracted from the 4AFC task. In the 4AFC task, sensitivity ratios were 38% of normal for deuteranomals and 19% of normal for protanomals. Yet, in the MDS results, color difference ratios were 86% of normal for deuteranomals and 67% of normal for protanomals. Thus, the contraction along the L/(L + M) axis shown in the perceptual color spaces of anomalous trichromats is far smaller than predicted by their reduced sensitivity, suggesting that an adaptive adjustment of postreceptoral gain may magnify the cone signals of anomalous trichromats to exploit the range of available postreceptoral neural signals.


Asunto(s)
Defectos de la Visión Cromática/fisiopatología , Visión de Colores/fisiología , Sensibilidad de Contraste/fisiología , Células Fotorreceptoras Retinianas Conos/fisiología , Adulto , Conducta de Elección , Pruebas de Percepción de Colores/métodos , Femenino , Humanos , Masculino , Umbral Sensorial/fisiología , Adulto Joven
16.
Laryngorhinootologie ; 93(4): 237-43, 2014 Apr.
Artículo en Alemán | MEDLINE | ID: mdl-24327352

RESUMEN

BACKGROUND: The Head and Neck Cancer Tumor Board is a multispeciality comprehensive conference that brings together experts with different backgrounds to make group decisions about the appropriate treatment. Due to the complexity of the patient cases and the collaboration of different medical disciplines most of these decisions have to be made under uncertainty, i. e., with-out knowing all relevant factors and without being quite sure about the outcome. METHODS: To develop effective team decision making under uncertainty, it is necessary to understand how medical experts perceive and handle uncertainties. The aim of this field study was to develop a knowledge base by exploring additionally the factors that influence group decision making processes. A structured nonparticipant observational study was employed to address the research goal. Video data were analyzed by 2 independent observers using an observation checklist. A total of 20 videotaped case discussions were studied. Observations were complemented by a questionnaire gathering subjective evaluations of board members about the process and quality of their decisions (N=15). RESULTS: The results show that uncertainty is recognized by board members. Reasons for uncertainty may stem from the complexity of the cases (e. g. therapy options) or the assessment from different disciplines coming together at the board. CONCLUSION: With respect to handling uncertainty and guaranteeing an optimal decision making process potential for improvement could be defined. This pertains to the handling of different levels of competence, the promotion of a positive discussion culture as well as structuring of the decision making process.


Asunto(s)
Conducta Cooperativa , Técnicas de Apoyo para la Decisión , Medicina Basada en la Evidencia , Comunicación Interdisciplinaria , Neoplasias de Oído, Nariz y Garganta/terapia , Competencia Clínica , Consenso , Humanos , Neoplasias de Oído, Nariz y Garganta/diagnóstico , Seguridad del Paciente , Encuestas y Cuestionarios , Incertidumbre , Grabación en Video
17.
Laryngorhinootologie ; 92(2): 97-101, 2013 Feb.
Artículo en Alemán | MEDLINE | ID: mdl-23247549

RESUMEN

BACKGROUND: Cancer support groups provide information and coping resources as well as represent patients' interests. To date it is unknown how often cancer patients post-laryngectomy use support groups and in which parameters users of support groups differ from non-users. MATERIAL AND METHODS: In a multicentre study, 224 laryngectomees were asked about their support group membership. Further, possible predictors for membership one year post-surgery were assessed. Data were collected with a semi-structured interview and standardized instruments. RESULTS: Overall, 23% of the laryngectomized patients are actively involved in cancer support groups. The probability of a membership increases if patients are well-educated, are living in good economic conditions and in a partnership, if they perceive low family support and wish additional counselling with a physician. CONCLUSION: A cancer support group seems to "buffer" family support perceived to be insufficient. However, support group users are living more frequently in a partnership and in good economic conditions compared to non-users. Physicians and speech therapists are important mediators to cancer support groups. They particularly should inform laryngectomees who are living in bad economic conditions and who are not living in a partnership about the availability of cancer support groups.


Asunto(s)
Neoplasias Laríngeas/psicología , Neoplasias Laríngeas/cirugía , Laringectomía/psicología , Grupos de Autoayuda/estadística & datos numéricos , Adulto , Anciano , Escolaridad , Femenino , Alemania , Humanos , Entrevista Psicológica , Masculino , Estado Civil , Persona de Mediana Edad , Probabilidad , Apoyo Social , Factores Socioeconómicos , Revisión de Utilización de Recursos
18.
HNO ; 60(1): 19-31, 2012 Jan.
Artículo en Alemán | MEDLINE | ID: mdl-22282007

RESUMEN

This article presents the current data and discussion on multimodal laryngeal preservation strategies in advanced laryngeal/hypopharyngeal carcinoma. Principally a distinction is made between simultaneous and induction chemoradiation protocols. In terms of late toxicity and related functional limitations, induction protocols are far superior to simultaneous platinum-based chemoradiation. Currently, the individual response to the first cycle of (short) induction chemotherapy appears to be the most reliable clinical marker for making treatment decisions, and this is under clinical investigation. No standard multimodal therapeutic alternative to laryngectomy exists; therefore, at this time multimodal strategies should only be carried out within the framework of clinical trials.


Asunto(s)
Antineoplásicos/uso terapéutico , Quimioradioterapia/métodos , Neoplasias Hipofaríngeas/terapia , Neoplasias Laríngeas/terapia , Tratamientos Conservadores del Órgano/tendencias , Selección de Paciente , Radioterapia Conformacional/métodos , Humanos , Neoplasias Hipofaríngeas/diagnóstico , Neoplasias Laríngeas/diagnóstico
19.
Laryngorhinootologie ; 90(10): 591-4, 2011 Oct.
Artículo en Alemán | MEDLINE | ID: mdl-22016255

RESUMEN

Since many years, the European Organisation for Research and Treatment of Cancer (EORTC) Quality of Life Group develops and validates measures for the assessment of quality of life in cancer patients, using high standards of methodology. These questionnaires are meant to be used primarily in clinical trials.As treatment strategies are changing and because of some -methodological criticism, the head and neck module EORTC QLQ-H&N35 is currently being revised and updated.In this paper, we will present the current state of work and other recent developments regarding the EORTC Quality of Life questionnaire development.


Asunto(s)
Comparación Transcultural , Neoplasias/terapia , Neoplasias de Oído, Nariz y Garganta/terapia , Calidad de Vida/psicología , Encuestas y Cuestionarios , Actividades Cotidianas/clasificación , Actividades Cotidianas/psicología , Europa (Continente) , Alemania , Humanos , Neoplasias/psicología , Neoplasias de Oído, Nariz y Garganta/psicología , Evaluación de Resultado en la Atención de Salud/estadística & datos numéricos , Psicometría/estadística & datos numéricos , Reproducibilidad de los Resultados , Programas Informáticos , Traducción
20.
Laryngorhinootologie ; 90(11): 657-62, 2011 Nov.
Artículo en Alemán | MEDLINE | ID: mdl-22083858

RESUMEN

Altered fractionated radiotherapy and concurrent chemoradiation could improve local control and survival for patients with locally advanced head and neck cancer. However, intensified treatment seems to increase late toxicity. Late swallowing dysfunction is common and has a large impact on quality of life and can get life-threatening character. Recent studies could show interrelations between the radiation dose to certain anatomical structures involved in the swallowing process and the risk of swallowing dysfunction. Important structures seem to be the pharyngeal constrictors and the supraglottic and glottic larynx. Further prospective clinical validations using standardized diagnostic protocols for dysphagia are necessary to establish dose constraints to anatomical structures involved in swallowing.


Asunto(s)
Trastornos de Deglución/radioterapia , Glotis/efectos de la radiación , Laringe/efectos de la radiación , Neoplasias de Oído, Nariz y Garganta/radioterapia , Músculos Faríngeos/efectos de la radiación , Traumatismos por Radiación/prevención & control , Radioterapia de Intensidad Modulada , Quimioradioterapia Adyuvante , Terapia Combinada , Trastornos de Deglución/diagnóstico por imagen , Fraccionamiento de la Dosis de Radiación , Glotis/diagnóstico por imagen , Humanos , Imagenología Tridimensional , Laringe/diagnóstico por imagen , Neoplasias de Oído, Nariz y Garganta/tratamiento farmacológico , Músculos Faríngeos/diagnóstico por imagen , Traumatismos por Radiación/diagnóstico por imagen , Planificación de la Radioterapia Asistida por Computador , Tomografía Computarizada por Rayos X
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