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1.
Eur Radiol ; 2024 May 20.
Artículo en Inglés | MEDLINE | ID: mdl-38769164

RESUMEN

OBJECTIVES: Somatostatin receptor positron emission tomography/computed tomography (SSTR-PET/CT) using [68Ga]-labeled tracers is a widely used imaging modality for neuroendocrine tumors (NET). Recently, [18F]SiTATE, a SiFAlin tagged [Tyr3]-octreotate (TATE) PET tracer, has shown great potential due to favorable clinical characteristics. We aimed to evaluate the reproducibility of Somatostatin Receptor-Reporting and Data System 1.0 (SSTR-RADS 1.0) for structured interpretation and treatment planning of NET using [18F]SiTATE. METHODS: Four readers assessed [18F]SiTATE-PET/CT of 95 patients according to the SSTR-RADS 1.0 criteria at two different time points. Each reader evaluated up to five target lesions per scan. The overall scan score and the decision on peptide receptor radionuclide therapy (PRRT) were considered. Inter- and intra-reader agreement was determined using the intraclass correlation coefficient (ICC). RESULTS: The ICC analysis on the inter-reader agreement using SSTR-RADS 1.0 for identical target lesions (ICC ≥ 85%), overall scan score (ICC ≥ 90%), and the decision to recommend PRRT (ICC ≥ 85%) showed excellent agreement. However, significant differences were observed in recommending PRRT among experienced readers (ER) (p = 0.020) and inexperienced readers (IR) (p = 0.004). Compartment-based analysis demonstrated good to excellent inter-reader agreement for most organs (ICC ≥ 74%), except for lymph nodes (ICC ≥ 53%). CONCLUSION: SSTR-RADS 1.0 represents a highly reproducible and consistent framework system for stratifying SSTR-targeted PET/CT scans, even using the novel SSTR-ligand [18F]SiTATE. Some inter-reader variability was observed regarding the evaluation of uptake intensity prior to PRRT as well as compartment scoring of lymph nodes, indicating that those categories require special attention during further clinical validation and might be refined in a future SSTR-RADS version 1.1. CLINICAL RELEVANCE STATEMENT: SSTR-RADS 1.0 is a consistent framework for categorizing somatostatin receptor-targeted PET/CT scans when using [18F]SiTATE. The framework serves as a valuable tool for facilitating and improving the management of patients with NET. KEY POINTS: SSTR-RADS 1.0 is a valuable tool for managing patients with NET. SSTR-RADS 1.0 categorizes patients with showing strong agreement across diverse reader expertise. As an alternative to [68Ga]-labeled PET/CT in neuroendocrine tumor imaging, SSTR-RADS 1.0 reliably classifies [18F]SiTATE-PET/CT.

2.
World J Urol ; 39(3): 943-951, 2021 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-32436072

RESUMEN

PURPOSE: To improve outcome prediction of extracorporeal shock wave lithotripsy (SWL) by development of a model based on easily available clinical and radiographical predictors and suitable for daily clinical use. MATERIALS AND METHODS: We evaluated predictive factors for SWL success in 517 consecutive patients suffering from urinary calculi who underwent SWL between 2010 and 2018. Analyses included descriptive statistics, receiver operating characteristic statistics and logistic regression. Predictive value was improved by combining parameters using model selection and recursive partitioning. RESULTS: Of the 517 patients, 310 (60.0%) had a successful SWL. Best individual predictor of SWL success was mean attenuation (MAV), with an area under the curve (AUC) of 0.668, and an optimal cutpoint (OC) of 987.5 HU. The best multivariable model, including MAV, stone size, skin to stone distance (SSD), presence of an indwelling stent, and four interaction effects, yielded an AUC of 0.736. Recursive partitioning would categorize patients into three outcome groups with high (76.9%), intermediate (41%) and low (10%) success probability. High probability of SWL success (76.9%) was found for patients with a stone with MAV ≤ 987 HU or with MAV > 987 HU but stone size ≤ 11 mm and SSD (45°) ≤ 88 mm. CONCLUSION: A model based on four established predictors, and provided as an Excel®-Tool, can clearly improve prediction of SWL success. In addition, patients can be classified into three defined outcome groups based on simple cutpoint combinations. Both tools improve informed decision-making in daily clinical practice and might reduce failure rates.


Asunto(s)
Litotricia , Cálculos Urinarios/terapia , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Femenino , Humanos , Masculino , Persona de Mediana Edad , Modelos Teóricos , Pronóstico , Estudios Retrospectivos , Resultado del Tratamiento , Adulto Joven
3.
Br J Dermatol ; 182(5): 1262-1268, 2020 05.
Artículo en Inglés | MEDLINE | ID: mdl-31378928

RESUMEN

BACKGROUND: Melanoma risk prediction models could be useful for matching preventive interventions to patients' risk. OBJECTIVES: To develop and validate a model for incident first-primary cutaneous melanoma using clinically assessed risk factors. METHODS: We used unconditional logistic regression with backward selection from the Australian Melanoma Family Study (461 cases and 329 controls) in which age, sex and city of recruitment were kept in each step, and we externally validated it using the Leeds Melanoma Case-Control Study (960 cases and 513 controls). Candidate predictors included clinically assessed whole-body naevi and solar lentigines, and self-assessed pigmentation phenotype, sun exposure, family history and history of keratinocyte cancer. We evaluated the predictive strength and discrimination of the model risk factors using odds per age- and sex-adjusted SD (OPERA) and the area under curve (AUC), and calibration using the Hosmer-Lemeshow test. RESULTS: The final model included the number of naevi ≥ 2 mm in diameter on the whole body, solar lentigines on the upper back (a six-level scale), hair colour at age 18 years and personal history of keratinocyte cancer. Naevi was the strongest risk factor; the OPERA was 3·51 [95% confidence interval (CI) 2·71-4·54] in the Australian study and 2·56 (95% CI 2·23-2·95) in the Leeds study. The AUC was 0·79 (95% CI 0·76-0·83) in the Australian study and 0·73 (95% CI 0·70-0·75) in the Leeds study. The Hosmer-Lemeshow test P-value was 0·30 in the Australian study and < 0·001 in the Leeds study. CONCLUSIONS: This model had good discrimination and could be used by clinicians to stratify patients by melanoma risk for the targeting of preventive interventions. What's already known about this topic? Melanoma risk prediction models may be useful in prevention by tailoring interventions to personalized risk levels. For reasons of feasibility, time and cost many melanoma prediction models use self-assessed risk factors. However, individuals tend to underestimate their naevus numbers. What does this study add? We present a melanoma risk prediction model, which includes clinically-assessed whole-body naevi and solar lentigines, and self-assessed risk factors including pigmentation phenotype and history of keratinocyte cancer. This model performs well on discrimination, the model's ability to distinguish between individuals with and without melanoma, and may assist clinicians to stratify patients by melanoma risk for targeted preventive interventions.


Asunto(s)
Lentigo , Melanoma , Neoplasias Cutáneas , Adolescente , Australia/epidemiología , Estudios de Casos y Controles , Humanos , Lentigo/epidemiología , Melanoma/diagnóstico , Melanoma/epidemiología , Melanoma/etiología , Factores de Riesgo , Neoplasias Cutáneas/epidemiología , Neoplasias Cutáneas/etiología
4.
J Eur Acad Dermatol Venereol ; 33(10): 1874-1885, 2019 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-31087403

RESUMEN

BACKGROUND: People at high risk of developing melanoma are usually identified by pigmentary and naevus phenotypes. OBJECTIVE: We examined whether associations of these phenotypes with melanoma risk differed by ambient sun exposure or participant characteristics in two population-based, case-control studies with comparable ancestry but different ambient sun exposure. METHODS: Data were analysed from 616 cases and 496 controls from the Australian Melanoma Family Study and 2012 cases and 504 controls from the Leeds (UK) case-control study. Questionnaire, interview and dermatological skin examination data were collected using the same measurement protocols. Relative risks were estimated as odds ratios using unconditional logistic regression, adjusted for potential confounders. RESULTS: Hair and skin colour were the strongest pigmentary phenotype risk factors. All associations of pigmentary phenotype with melanoma risk were similar across countries. The median number of clinically assessed naevi was approximately three times higher in Australia than Leeds, but the relative risks for melanoma associated with each additional common or dysplastic naevus were higher for Leeds than Australia, especially for naevi on the upper and lower limbs. Higher naevus counts on the head and neck were associated with a stronger relative risk for melanoma for women than men. The two countries had similar relative risks for melanoma based on self-reported naevus density categories, but personal perceptions of naevus number differed by country. There was no consistent evidence of interactions between phenotypes on risk. CONCLUSIONS: Classifying people at high risk of melanoma based on their number of naevi should ideally take into account their country of residence, type of counts (clinical or self-reported), body site on which the naevus counts are measured and sex. The presence of naevi may be a stronger indicator of a genetic predisposition in the UK than in Australia based on less opportunity for sun exposure to influence naevus development.


Asunto(s)
Exposición a Riesgos Ambientales , Melanoma/etnología , Nevo Pigmentado/etnología , Neoplasias Cutáneas/etnología , Pigmentación de la Piel , Luz Solar , Adolescente , Adulto , Anciano , Australia/epidemiología , Estudios de Casos y Controles , Extremidades , Femenino , Color del Cabello , Humanos , Masculino , Persona de Mediana Edad , Nevo Pigmentado/patología , Fenotipo , Medición de Riesgo , Factores de Riesgo , Factores Sexuales , Neoplasias Cutáneas/patología , Carga Tumoral , Reino Unido/epidemiología , Población Blanca , Adulto Joven
5.
World J Urol ; 36(7): 1085-1091, 2018 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-29497859

RESUMEN

PURPOSE: To establish whether bipolar transurethral resection of tumours (bTURB) on the lateral bladder wall is superior to monopolar transurethral resection (mTURB) of such tumours. To our knowledge, this is the first prospective randomised study, which defines complete resection depending on obturator jerk as primary endpoint. METHODS: In a prospective, randomised, single centre study, 52 patients with newly diagnosed or recurrent bladder tumour on the lateral bladder wall were enrolled and randomised to undergo mTURB or bTURB; 44 patients were eligible for analysis, of whom 21 underwent mTURB and 23 bTURB. Any differences between the two techniques related to the incidence of unwanted stimulation of the obturator nerve and subsequent adductor spasms were evaluated. All procedures were carried out under laryngeal mask anaesthesia without obturator nerve block (ONB) and without drug-induced relaxation. RESULTS: Baseline characteristics of the two study groups did not differ statistically significantly. The success rate defined as complete resection of the bladder tumour without any clinically relevant adductor spasm was 61.9% in the monopolar group and 82.6% in the bipolar group (p = 0.18). CONCLUSIONS: Complete, undisturbed resection of tumours of the lateral bladder wall is feasible with mTURB and bTURB. Adductor spasms due to obturator jerk can occur suddenly with the risk of bladder perforation. We therefore support ONB when using spinal anaesthesia and drug-induced relaxation when using general anaesthesia when performing TURB on the lateral bladder wall.


Asunto(s)
Recurrencia Local de Neoplasia/cirugía , Bloqueo Nervioso , Nervio Obturador , Espasmo/etiología , Neoplasias de la Vejiga Urinaria/cirugía , Procedimientos Quirúrgicos Urológicos/métodos , Anciano , Anciano de 80 o más Años , Femenino , Humanos , Masculino , Persona de Mediana Edad , Recurrencia Local de Neoplasia/patología , Estudios Prospectivos , Carga Tumoral , Neoplasias de la Vejiga Urinaria/patología
6.
World J Urol ; 36(12): 2073-2080, 2018 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-29845319

RESUMEN

OBJECTIVES: To evaluate the predictive value of advanced non-contrasted computed tomography (NCCT) post-processing using novel CT-calculometry (CT-CM) parameters compared to established predictors of success of shock wave lithotripsy (SWL) for urinary calculi. MATERIALS AND METHODS: NCCT post-processing was retrospectively performed in 312 patients suffering from upper tract urinary calculi who were treated by SWL. Established predictors such as skin to stone distance, body mass index, stone diameter or mean stone attenuation values were assessed. Precise stone size and shape metrics, 3-D greyscale measurements and homogeneity parameters such as skewness and kurtosis, were analysed using CT-CM. Predictive values for SWL outcome were analysed using logistic regression and receiver operating characteristics (ROC) statistics. RESULTS: Overall success rate (stone disintegration and no re-intervention needed) of SWL was 59% (184 patients). CT-CM metrics mainly outperformed established predictors. According to ROC analyses, stone volume and surface area performed better than established stone diameter, mean 3D attenuation value was a stronger predictor than established mean attenuation value, and parameters skewness and kurtosis performed better than recently emerged variation coefficient of stone density. Moreover, prediction of SWL outcome with 80% probability to be correct would be possible in a clearly higher number of patients (up to fivefold) using CT-CM-derived parameters. CONCLUSIONS: Advanced NCCT post-processing by CT-CM provides novel parameters that seem to outperform established predictors of SWL response. Implementation of these parameters into clinical routine might reduce SWL failure rates.


Asunto(s)
Procesamiento de Imagen Asistido por Computador , Cálculos Renales/diagnóstico por imagen , Litotricia , Cálculos Ureterales/diagnóstico por imagen , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Femenino , Humanos , Imagenología Tridimensional , Cálculos Renales/terapia , Modelos Logísticos , Masculino , Persona de Mediana Edad , Pronóstico , Curva ROC , Estudios Retrospectivos , Tomografía Computarizada por Rayos X , Cálculos Ureterales/terapia , Adulto Joven
7.
Nano Lett ; 17(5): 2816-2824, 2017 05 10.
Artículo en Inglés | MEDLINE | ID: mdl-28383924

RESUMEN

III-V compound semiconductors are indispensable materials for today's high-end electronic and optoelectronic devices and are being explored for next-generation transistor logic and quantum technologies. III-V surfaces and interfaces play the leading role in determining device performance, and therefore, methods to control their electronic properties have been developed. Typically, surface passivation studies demonstrated how to limit the density of surface states. Strain has been widely used to improve the electronic transport properties and optoelectronic properties of III-Vs, but the potential of this technology to modify the surface properties still remains to be explored. Here we show that uniaxial stress induces a shift in the energy of the surface states of III-V nanowires, modifying their electronic properties. We demonstrate this phenomenon by modulating the conductivity of InAs nanowires over 4 orders of magnitude with axial strain ranging between -2.5% in compression and 2.1% in tension. The band bending at the surface of the nanostructure is modified from accumulation to depletion reversibly and reproducibly. We provide evidence of this physical effect using a combination of electrical transport measurement, Raman spectroscopy, band-structure modeling, and technology computer aided design (TCAD) simulations. With this methodology, the deformation potentials for the surface states are quantified. These results reveal that strain technology can be used to shift surface states away from energy ranges in which device performance is negatively affected and represent a novel route to engineer the electronic properties of III-V devices.

8.
Strahlenther Onkol ; 192(3): 182-9, 2016 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-26713323

RESUMEN

BACKGROUND AND PURPOSE: For localized prostate cancer, treatment options include external beam radiotherapy (EBRT), radical prostatectomy (RP), and brachytherapy (BT). Erectile dysfunction (ED) is a common side-effect. Our aim was to evaluate penile erectile function (EF) before and after BT, EBRT, or RP using a validated self-administered quality-of-life survey from a prospective registry. MATERIAL AND METHODS: Analysis included 478 patients undergoing RP (n = 252), EBRT (n = 91), and BT (n = 135) with at least 1 year of follow-up and EF documented using IIEF-5 scores at baseline, 6 weeks, 6 months, 1 year, and annually thereafter. RESULTS: Differences among treatments were most pronounced among patients with no or mild initial ED (IIEF-5 ≥ 17). Overall, corrected for baseline EF and age, BT was associated with higher IIEF-5 scores than RP (+ 7.8 IIEF-5 score) or EBRT (+ 3.1 IIEF-5 score). EBRT was associated with better IIEF-5 scores than RP (+ 4.7 IIEF-5 score). In patients undergoing EBRT or RP with bilateral nerve sparing (NS), recovery of EF was observed and during follow-up, the differences to BT were not statistically significant. Overall age had a negative impact on EF preservation (corrected for baseline IIEF). CONCLUSION: In our series, EF was adversely affected by each treatment modality. Considered overall, BT provided the best EF preservation in comparison to EBRT or RP.


Asunto(s)
Braquiterapia/estadística & datos numéricos , Disfunción Eréctil/epidemiología , Prostatectomía/estadística & datos numéricos , Neoplasias de la Próstata/epidemiología , Neoplasias de la Próstata/terapia , Radioterapia Conformacional/estadística & datos numéricos , Adulto , Distribución por Edad , Anciano , Anciano de 80 o más Años , Causalidad , Comorbilidad , Disfunción Eréctil/prevención & control , Alemania/epidemiología , Humanos , Incidencia , Masculino , Persona de Mediana Edad , Complicaciones Posoperatorias/epidemiología , Traumatismos por Radiación/epidemiología , Estudios Retrospectivos , Factores de Riesgo , Resultado del Tratamiento
10.
Nanotechnology ; 25(30): 305702, 2014 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-25004861

RESUMEN

Precise measurements of a complete set of thermoelectric parameters on a single indium-arsenide nanowire (NW) have been performed using highly sensitive, micro-fabricated sensing devices based on the heater/sensor principle. The devices were fabricated as micro electro-mechanical systems consisting of silicon nitride membranes structured with resistive gold heaters/sensors. Preparation, operation and characterization of the devices are described in detail. Thermal decoupling of the heater/sensor platforms has been optimized reaching thermal conductances as low as 20 nW K(-1) with a measurements sensitivity below 20 nW K(-1). The InAs NWs were characterized in terms of thermal conductance, four-probe electrical conductance and thermopower (Seebeck coefficient), all measured on a single NW. The temperature dependence of the parameters determining the thermoelectric figure-of-merit of an InAs NW was acquired in the range 200-350 K featuring a minor decrease of the thermal conductivity from 2.7 W (m K)(-1) to 2.3 W (m K)(-1).

11.
Klin Monbl Augenheilkd ; 230(12): 1251-6, 2013 Dec.
Artículo en Alemán | MEDLINE | ID: mdl-24327288

RESUMEN

BACKGROUND: Age-related macular degeneration (AMD) affects the quality of life of about 40,000 patients in Switzerland. The treatment of wet AMD with intravitreal injected anti-vascular endothelial growth factor (VEGF) can be a heavy burden for many patients. The aim of this study was to understand the quality of life of the patients and to seek ways to improve the treatment compliance. METHODS: Half-structured telephone interviews with 28 patients between 56 and 94 years of age were transcribed and analysed. In 21 patients, both eyes were concerned with AMD. RESULTS: The quality of life of patients with AMD is reduced. Many activities of daily living are hindered. Dependence on others increases. Communication of the diagnosis is perceived as a shock. Most interviewees wish for more information about their specific situation. Auxiliary means and counselling possibilities are hardly known. CONCLUSION: Wet AMD impacts on the quality of life of the patient. Treatment should therefore not be limited to the medical treatment of the ill eye. Triage to rehabilitation and counselling services should be included as important duties of the medical practitioners.


Asunto(s)
Actividades Cotidianas/psicología , Adaptación Psicológica , Cumplimiento de la Medicación/psicología , Soluciones Oftálmicas/uso terapéutico , Calidad de Vida/psicología , Degeneración Macular Húmeda/tratamiento farmacológico , Degeneración Macular Húmeda/psicología , Anciano , Anciano de 80 o más Años , Femenino , Humanos , Masculino , Persona de Mediana Edad , Suiza , Resultado del Tratamiento , Factor A de Crecimiento Endotelial Vascular/antagonistas & inhibidores
12.
Urologie ; 62(11): 1200-1203, 2023 Nov.
Artículo en Alemán | MEDLINE | ID: mdl-37367951

RESUMEN

Melanosis of the urinary bladder is an extremely rare benign condition in which melanin deposits occur in the urothelial and stromal cells. We report such a case in which melanosis of the urinary bladder was detected in a 55-year-old woman with known multiple sclerosis during an extended workup due to urinary urgency complaints. The findings were confirmed by biopsy.


Asunto(s)
Melanosis , Enfermedades de la Vejiga Urinaria , Trastornos Urinarios , Femenino , Humanos , Persona de Mediana Edad , Vejiga Urinaria/patología , Enfermedades de la Vejiga Urinaria/diagnóstico , Trastornos Urinarios/patología , Cistoscopía , Melanosis/diagnóstico , Enfermedades Raras/patología
13.
Exp Eye Res ; 103: 90-8, 2012 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-22960304

RESUMEN

The neuropeptide somatostatin and selective analogs for the sst(2/5) receptor subtypes provided neuroprotection against retinal chemical ischemia ex vivo and AMPA [(RS)-α-Amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid hydrobromide] induced retinal toxicity in vivo, when employed in micromolar concentrations (Mastrodimou et al., 2005; Kiagiadaki and Thermos, 2008). The aim of the present study was to investigate the neuroprotective properties of a new metabolically stable agent pasireotide (SOM230) in the above mentioned retinal models of ischemia. Adult Sprague Dawley (250-350 g) rats were employed. For the ex vivo experiments, retinal eye cups were incubated with PBS or the chemical ischemia mixture [iodoacetic acid (5 mM)/sodium cyanide (25 mM)] in the absence or presence of SOM230 (10(-7)-10(-5) M) alone or in the presence of the sst(2) antagonist CYN-154806 (10(-7) or 10(-5) M). In the in vivo model, the animals received intravitreally: PBS (50 mM), AMPA (42 nmol/eye) or AMPA (42 nmol) in combination with SOM230 (10(-7)-10(-5) M). Immunohistochemistry studies using antisera against bNOS, a marker for brain/neuronal NOS containing amacrine cells, protein kinase C (PKC) a marker for rod bipolar cells, and TUNEL studies in conjunction with FACS analysis were employed to examine retinal cell loss and protection. Chemical ischemia led to a loss of bNOS and PKC immunoreactivity which was reversed by SOM230. Partial and full protection of bNOS and PKC immunoreactive neurons, respectively, was observed even at the low concentration of 10(-7) M. The neuroprotective actions of SOM230 (10(-7) or 10(-5) M) were reversed by CYN-154806 (10(-7) or 10(-5) M, respectively). Similarly, SOM230 (10(-7), 10(-6), 10(-5) M) provided neuroprotection in the in vivo model. The dose of 10(-7) M prevented the loss of the bNOS cells and provided almost full protection. These data were substantiated by TUNEL staining and fluorescence-activated cell sorting (FACS) analysis. SOM230 appears very efficacious in its neuroprotective properties in both models of retinal ischemia affording neuroprotection at the concentration or dose of 100 nM. These data suggest that SOM230 might represent a useful pharmacological compound for the treatment of retinal disease.


Asunto(s)
Modelos Animales de Enfermedad , Fármacos Neuroprotectores/uso terapéutico , Daño por Reperfusión/prevención & control , Enfermedades de la Retina/prevención & control , Somatostatina/análogos & derivados , Células Amacrinas/enzimología , Animales , Apoptosis/efectos de los fármacos , Citometría de Flujo , Técnica del Anticuerpo Fluorescente Indirecta , Etiquetado Corte-Fin in Situ , Óxido Nítrico Sintasa de Tipo I/metabolismo , Oligopéptidos/uso terapéutico , Proteína Quinasa C/metabolismo , Ratas , Ratas Sprague-Dawley , Receptores de Somatostatina/antagonistas & inhibidores , Daño por Reperfusión/enzimología , Daño por Reperfusión/patología , Enfermedades de la Retina/enzimología , Enfermedades de la Retina/patología , Somatostatina/uso terapéutico
14.
World J Urol ; 30(4): 525-31, 2012 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-21928123

RESUMEN

INTRODUCTION AND OBJECTIVES: To evaluate retrospectively kidney-specific cadherin (Ksp-cad) expression in renal cell carcinoma (RCC) subtypes and oncocytoma in correlation with its ontogenetic origin of distal and proximal tubules and to correlate Ksp-cad expression with tumour characteristics. MATERIALS AND METHODS: Membranous and cytoplasmic expression of Ksp-cad was determined in 40 clear cell (ccRCC), 25 papillary (pRCC), 19 chromophobe carcinomas (chRCC), 27 oncocytomas (oncocytomas) (n = 111) and 32 benign kidney parenchyma specimens separated in distal tubules (DT) and proximal tubules (PT) by immunohistochemistry using tissue microarray technique. Staining intensity was quantified as a score ranging from 0 to 12. Comparison of data and correlation with tumour characteristics were done by Wilcoxon/Kruskal-Wallis tests (post hoc Tukey-Kramer analysis). RESULTS: In benign renal tissue, membranous and cytoplasmic expression of Ksp-cad in the DT was significantly higher than that in the PT (12.0 ± 0 vs. 5.2 ± 0.3 and 6.3 ± 0.5 vs. 0.0 ± 0.0, respectively; (P < 0.05)). Membranous KSP-cad expression was significantly higher in chRCC (5.2 ± 0.8) and oncocytomas (3.7 ± 0.4) than that in ccRCC (0.8 ± 0.2) and pRCC (1.4 ± 0.4; P < 0.05), while expression between oncocytomas and chRCC did not differ significantly. In RCC, Ksp-cad expression was significantly associated with higher T stage and the occurrence of synchronous metastasis (P < 0.05). Higher N stages and grading tended to correlate with a lower Ksp-cad expression. CONCLUSIONS: In this cohort, the origin of tumour subtypes-chRCC and oncocytomas develop from DT and ccRCC and pRCC from PT cells-is mirrored by the respective Ksp-cad expression. This raises the question whether DT-derived tumours have a less malignant potential than PT-derived tumours.


Asunto(s)
Adenoma Oxifílico/patología , Biomarcadores de Tumor/metabolismo , Cadherinas/metabolismo , Carcinoma de Células Renales/patología , Neoplasias Renales/patología , Índice de Severidad de la Enfermedad , Adenoma Oxifílico/clasificación , Adenoma Oxifílico/metabolismo , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Carcinoma de Células Renales/clasificación , Carcinoma de Células Renales/metabolismo , Linaje de la Célula , Estudios de Cohortes , Femenino , Humanos , Riñón/metabolismo , Riñón/patología , Neoplasias Renales/clasificación , Neoplasias Renales/metabolismo , Túbulos Renales Distales/metabolismo , Túbulos Renales Distales/patología , Túbulos Renales Proximales/metabolismo , Túbulos Renales Proximales/patología , Masculino , Persona de Mediana Edad , Estadificación de Neoplasias , Estudios Retrospectivos , Adulto Joven
15.
Gen Comp Endocrinol ; 178(2): 436-9, 2012 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-22634958

RESUMEN

SOM230 (pasireotide, Signifor), a recently developed somatostatin analog, has been tested in ACTH-secreting pituitary tumors with promising results. No study has yet evaluated whether this analog also directly affects adrenal steroid production. The aim of the current study was to evaluate whether SOM230 modulates corticosteroid secretion by normal adrenals in vitro. Primary cultures from normal human and rat adrenals were incubated with 10-100 nM SOM230 with and without 10nM ACTH. Dose-response studies with 1 nM-1 µM SOM230 were performed on rat adrenals. Cortisol/corticosterone levels in medium were measured after 4 and 24h. SOM230 (10nM) significantly increased corticosteroid levels after 24h incubation in both human (36.4 ± 0.43 ng/well vs 27.7 ± 3.17 ng/well, p<0.05) and rat (16.2 ± 1.16 ng/well vs 11.6 ± 0.92 ng/well p<0.05) adrenals; lesser effects were observed with 100 nM SOM (33.4 ± 2.59 ng/well vs 27.7 ± 3.17 ng/well p<0.05; 13.4 ± 0.82 ng/well vs 11.6 ± 0.92 ng/well, N.S. vs baseline secretion for human and rat adrenals, respectively). Dose-response curves confirmed maximal effect at 10nM SOM230. The corticosteroid secretory response to ACTH was unaffected by SOM230 co-incubation. In conclusion, SOM230 exerts a moderate stimulatory effect on adrenal corticosteroid secretion in vitro. This argues against a direct adrenal involvement in the clinical efficacy of SOM230 in patients with ACTH-secreting pituitary tumors and widens the known range of action of SOM230.


Asunto(s)
Glándulas Suprarrenales/efectos de los fármacos , Glándulas Suprarrenales/metabolismo , Corticosterona/metabolismo , Somatostatina/análogos & derivados , Animales , Células Cultivadas , Humanos , Ratas , Somatostatina/agonistas , Somatostatina/farmacología
16.
Proc Natl Acad Sci U S A ; 105(49): 19336-41, 2008 Dec 09.
Artículo en Inglés | MEDLINE | ID: mdl-19052233

RESUMEN

The availability of nitrogen represents a key constraint on carbon cycling in terrestrial ecosystems, and it is largely in this capacity that the role of N in the Earth's climate system has been considered. Despite this, few studies have included continuous variation in plant N status as a driver of broad-scale carbon cycle analyses. This is partly because of uncertainties in how leaf-level physiological relationships scale to whole ecosystems and because methods for regional to continental detection of plant N concentrations have yet to be developed. Here, we show that ecosystem CO(2) uptake capacity in temperate and boreal forests scales directly with whole-canopy N concentrations, mirroring a leaf-level trend that has been observed for woody plants worldwide. We further show that both CO(2) uptake capacity and canopy N concentration are strongly and positively correlated with shortwave surface albedo. These results suggest that N plays an additional, and overlooked, role in the climate system via its influence on vegetation reflectivity and shortwave surface energy exchange. We also demonstrate that much of the spatial variation in canopy N can be detected by using broad-band satellite sensors, offering a means through which these findings can be applied toward improved application of coupled carbon cycle-climate models.


Asunto(s)
Carbono/metabolismo , Clima , Ecosistema , Nitrógeno/metabolismo , Árboles/metabolismo , Monitoreo del Ambiente/métodos , Retroalimentación , Modelos Biológicos , Hojas de la Planta/metabolismo , Nave Espacial , Temperatura
17.
Nanotechnology ; 21(43): 435202, 2010 Oct 29.
Artículo en Inglés | MEDLINE | ID: mdl-20890021

RESUMEN

In this work we investigate doping by solid-state diffusion from a doped oxide layer, obtained by plasma-enhanced chemical vapor deposition (PECVD), as a means for selectively doping silicon nanowires (NWs). We demonstrate both n-type (phosphorous) and p-type (boron) doping up to concentrations of 10(20) cm(-3), and find that this doping mechanism is more efficient for NWs as opposed to planar substrates. We observe no diameter dependence in the range of 25 to 80 nm, which signifies that the NWs are uniformly doped. The drive-in temperature (800-950 °C) can be used to adjust the actual doping concentration in the range 2 × 10(18) to 10(20) cm(-3). Furthermore, we have fabricated NMOS and PMOS devices to show the versatility of this approach and the possibility of achieving segmented doping of NWs. The devices show high I(on)/I(off) ratios of around 10(7) and, especially for the PMOS, good saturation behavior and low hysteresis.

18.
Vasa ; 39(4): 325-33, 2010 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-21104622

RESUMEN

BACKGROUND: The predictive value of PROCAM, FRAMINGHAM, SCORE and SMART-score to estimate the cardiovascular risk in patients with overt atherosclerosis had never been assessed. PATIENTS AND METHODS: 96 consecutive patients with clinically evident atherosclerosis (coronary, cerebrovascular, peripheral artery and renovascular disease) were enrolled in this preliminary observational study. At baseline, medical history and blood chemistry were obtained. Sonographic measurement of the intima-media thickness (IMT) in the common carotid artery was performed and risk estimations according to the above listed risk scores were calculated. During a 6 year follow-up the occurrence of cardiovascular death, acute coronary syndrome and stroke was assessed. RESULTS: Mean (±SD) risk-scores were 10.9±2.5, range 6-17 (SMART); 18.9±18.2%; range 0.2-94.1% (PROCAM); 21.4±13.1%, range 4-56% (FRAMINGHAM); and 4.8±3.9%, range 0.4-15.3% (SCORE). Mean IMT was 0.84±0.14 mm, range 0.51-1.20 mm. All scores correlate significantly with each other (r>0.321; p<0.01), but only SMART-score correlated significantly with baseline IMT(r=0.372; p<0.001). Within the median follow-up of 73 months, a cardiovascular endpoint was observed in 36 (42%) patients. The AUC (95% confidence interval) for SMART-risk-score predicting a cardiovascular event was 0.67 (0.54-0.77; p<0.02); for PROCAM 0.60 (0.47-0.73; p=n.s.); for FRAMINGHAM 0.56 (0.43-0.69; p=n.s.); and for SCORE 0.60 (0.46-0.73; p=n.s.). Cox regression analysis showed a relative risk for a cardiovascular event per additional SMART score point of 1.15 (95% CI 1.01-1.30 p=0.03). CONCLUSIONS: PROCAM-, FRAMINGHAM- and SCORE-risk score seem to be barely useful in a secondary prevention setting. In patients with overt atherosclerosis, the cardiovascular risk seems to be better assessed by means of the SMART score.


Asunto(s)
Aterosclerosis/complicaciones , Aterosclerosis/mortalidad , Enfermedades Cardiovasculares/etiología , Enfermedades Cardiovasculares/mortalidad , Indicadores de Salud , Anciano , Anciano de 80 o más Años , Aterosclerosis/diagnóstico por imagen , Aterosclerosis/terapia , Enfermedades Cardiovasculares/prevención & control , Femenino , Estudios de Seguimiento , Humanos , Estimación de Kaplan-Meier , Masculino , Persona de Mediana Edad , Proyectos Piloto , Valor Predictivo de las Pruebas , Prevención Primaria , Pronóstico , Modelos de Riesgos Proporcionales , Estudios Prospectivos , Medición de Riesgo , Factores de Riesgo , Prevención Secundaria , Suiza , Factores de Tiempo , Ultrasonografía Doppler Dúplex
19.
J Cell Biol ; 93(3): 893-8, 1982 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-6811601

RESUMEN

Two distinct forms of globin messenger RNA were isolated from mouse spleen cells infected with Friend erythroleukemia virus: polyribosomal messenger ribonucleoprotein particles (15S mRNP), and their corresponding protein-free mRNAs obtained by chemical deproteinization. The translation efficiencies of both messenger forms were assayed in a Krebs II ascites cell-free system. Selective removal of RNA-binding proteins from the ascites cell lysate did not affect globin synthesis when the mRNA was supplied as 15S mRNP; deproteinized mRNA however was not translated. Only in the presence of two fractions of RNA-binding proteins was the protein-free mRNA translated. Some of the RNA-binding proteins have the same molecular weights and isoelectric points as the principal proteins of 15S mRNP.


Asunto(s)
Proteínas Portadoras/fisiología , Globinas/biosíntesis , ARN Mensajero/fisiología , Animales , Fraccionamiento Celular , Sistema Libre de Células , Virus de la Leucemia Murina de Friend , Globinas/genética , Leucemia Experimental/genética , Ratones , Ratones Endogámicos BALB C , Biosíntesis de Proteínas , Proteínas de Unión al ARN , Ribonucleoproteínas/análisis , Bazo/metabolismo
20.
Science ; 276(5313): 779-81, 1997 May 02.
Artículo en Inglés | MEDLINE | ID: mdl-9115199

RESUMEN

Microfluidic networks (microFNs) were used to pattern biomolecules with high resolution on a variety of substrates (gold, glass, or polystyrene). Elastomeric microFNs localized chemical reactions between the biomolecules and the surface, requiring only microliters of reagent to cover square millimeter-sized areas. The networks were designed to ensure stability and filling of the microFN and allowed a homogeneous distribution and robust attachment of material to the substrate along the conduits in the microFN. Immunoglobulins patterned on substrates by means of microFNs remained strictly confined to areas enclosed by the network with submicron resolution and were viable for subsequent use in assays. The approach is simple and general enough to suggest a practical way to incorporate biological material on technological substrates.


Asunto(s)
Dimetilpolisiloxanos , Vidrio , Oro , Inmunoglobulina G , Poliestirenos , Siliconas , Adhesividad , Animales , Fenómenos Químicos , Química Física , Pollos , Ensayo de Inmunoadsorción Enzimática , Goma , Propiedades de Superficie
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