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1.
Surg Endosc ; 36(5): 3533-3541, 2022 05.
Artículo en Inglés | MEDLINE | ID: mdl-34459976

RESUMEN

BACKGROUND: Coffee is a widely consumed beverage. Surgeons often drink coffee before performing surgery. Caffeine intake leads to tremor which might have a negative effect on surgeons' fine motor skills. METHODS: A double-blinded parallel-group trial was conducted in order to investigate if caffeinated coffee intake has a negative effect on laparoscopic skills and increases tremor, regardless of previous coffee consumption. 118 participants were selected during a congress of the German Society of Surgery. Exclusion criteria were immaturity and no given consent. Participants and investigators were blinded. Participants were randomized with a 1:1 allocation into interventional group receiving caffeinated coffee or placebo group receiving decaffeinated coffee. The motor skills were tested with two validated laparoscopic exercises at a laparoscopy simulator (LapSim®) before and 30 min after coffee intake. Data on influencing factors were recorded in a standardized questionnaire and tested for equal distribution in both groups. In both exercises four parameters were recorded: left and right hand path length and angular path. Their differences and the resulting effect scores were calculated for both groups as primary outcome to test which group showed greater improvement on the second round of exercises. Registration number DRKS00023608, registered retrospectively. RESULTS: Fifty nine subjects were assigned to each the interventional (54 analyzed) and placebo group (53 analyzed) with 11 drop outs. There was no significant difference between the placebo and interventional group in the two exercises in effect score 30 min after coffee intake [mean (SD); 38.58 (10.66) vs. 41.73 (7.40) and 113.09 (28.94) vs. 116.59 (25.63)]. A significant improvement from first to second measurement in the first exercise could be observed for both groups, demonstrating the training effect. CONCLUSION: In our study, we verified that additional caffeinated coffee intake, e.g., during a coffee break, does not lead to deterioration of laparoscopic fine motor skills.


Asunto(s)
Café , Laparoscopía , Cafeína , Método Doble Ciego , Humanos , Estudios Retrospectivos , Temblor
2.
Arch Toxicol ; 88(3): 701-23, 2014 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-24374802

RESUMEN

For more than two decades, scientists have been trying to replace the regulatory in vivo Draize eye test by in vitro methods, but so far only partial replacement has been achieved. In order to better understand the reasons for this, historical in vivo rabbit data were analysed in detail and resampled with the purpose of (1) revealing which of the in vivo endpoints are most important in driving United Nations Globally Harmonized System/European Union Regulation on Classification, Labelling and Packaging (UN GHS/EU CLP) classification for serious eye damage/eye irritation and (2) evaluating the method's within-test variability for proposing acceptable and justifiable target values of sensitivity and specificity for alternative methods and their combinations in testing strategies. Among the Cat 1 chemicals evaluated, 36-65 % (depending on the database) were classified based only on persistence of effects, with the remaining being classified mostly based on severe corneal effects. Iritis was found to rarely drive the classification (<4 % of both Cat 1 and Cat 2 chemicals). The two most important endpoints driving Cat 2 classification are conjunctiva redness (75-81 %) and corneal opacity (54-75 %). The resampling analyses demonstrated an overall probability of at least 11 % that chemicals classified as Cat 1 by the Draize eye test could be equally identified as Cat 2 and of about 12 % for Cat 2 chemicals to be equally identified as No Cat. On the other hand, the over-classification error for No Cat and Cat 2 was negligible (<1 %), which strongly suggests a high over-predictive power of the Draize eye test. Moreover, our analyses of the classification drivers suggest a critical revision of the UN GHS/EU CLP decision criteria for the classification of chemicals based on Draize eye test data, in particular Cat 1 based only on persistence of conjunctiva effects or corneal opacity scores of 4. In order to successfully replace the regulatory in vivo Draize eye test, it will be important to recognise these uncertainties and to have in vitro tools to address the most important in vivo endpoints identified in this paper.


Asunto(s)
Ojo/efectos de los fármacos , Irritantes/clasificación , Irritantes/toxicidad , Pruebas de Toxicidad/métodos , Animales , Conjuntiva/efectos de los fármacos , Córnea/efectos de los fármacos , Bases de Datos Factuales , Evaluación Preclínica de Medicamentos/métodos , Unión Europea , Probabilidad , Conejos , Estudios Retrospectivos , Pruebas de Toxicidad/normas , Naciones Unidas
3.
J Surg Res ; 185(2): 676-83, 2013 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-23845866

RESUMEN

BACKGROUND: Despite various attempts at modifying usual treatment modalities, anaplastic thyroid cancer (ATC) is still associated with unfavorable prognosis. Results of preclinical investigations are often of limited transferability to clinical tumor biology. Individualized multimodal treatment regimens, including novel growth-inhibiting drugs, might be a future option. METHODS: Tumor tissue, freshly prepared from a patient operated for ATC, was xenotransplanted to nude mice. While the patient obtained a hyperfractionated external beam radiation, mice carrying xenotransplanted tumors were randomized (n = 6) and treated by multikinase inhibitors (sorafenib [S]: vascular endothelial growth factor receptor [VEGF-R], platelet derived growth factor receptor, RET; vandetanib [V]: VEGF-R, endothelial growth factor receptor [EGF-R]; and MLN8054 [M]: Aurora kinases [AK]). Antiproliferative, antiangiogenic, and proapoptotic effects were evaluated. RESULTS: Treatment of successfully xenotransplanted fresh ATC tumor tissue by multikinase inhibitors and aurora kinase inhibitor reduced the tumor volume up to 61% depending on the drug and time of application (3 wk of treatment: 46% [M], 34% [V], 30% [S]; 5 wk of treatment: 61% [S]). Tumor cell proliferation (BrdU) was reduced between 34% and 58% [S] and [V]. Reduction of tumor vascularity was between 67% [V] and 33% [S] and was accompanied by decreased EGF-R/VEGF-R2 receptor activity [V/V,S]. Tumor cell apoptosis (caspase 3 activity) increased up to 2.4-fold [S]. CONCLUSIONS: Successful in vivo evaluation of novel drugs in xenotransplanted fresh tumor tissue allows in-time (while patient receives standard treatment) prospective analysis for possible additional clinical application. However, technical specifications have to be taken into account to obtain stable in vivo tumor growth. Based on the individual results, a tailored clinical drug application seems possible.


Asunto(s)
Benzazepinas/farmacología , Niacinamida/análogos & derivados , Compuestos de Fenilurea/farmacología , Piperidinas/farmacología , Quinazolinas/farmacología , Neoplasias de la Tiroides/tratamiento farmacológico , Animales , Apoptosis/efectos de los fármacos , Proliferación Celular/efectos de los fármacos , Evaluación Preclínica de Medicamentos , Humanos , Masculino , Ratones , Ratones Desnudos , Persona de Mediana Edad , Neovascularización Patológica/tratamiento farmacológico , Niacinamida/farmacología , Inhibidores de Proteínas Quinasas/farmacología , Distribución Aleatoria , Receptores de Factores de Crecimiento Endotelial Vascular/antagonistas & inhibidores , Sorafenib , Carcinoma Anaplásico de Tiroides , Neoplasias de la Tiroides/patología , Neoplasias de la Tiroides/cirugía , Resultado del Tratamiento , Ensayos Antitumor por Modelo de Xenoinjerto
4.
J Cell Biochem ; 98(4): 954-65, 2006 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-16475167

RESUMEN

Tumor angiogenesis is believed to result from an imbalance of pro- and anti-angiogenic factors, some of which are candidates for targeted therapy. Such therapy has raised hopes for patients with undifferentiated thyroid carcinomas, who are facing a grave prognosis with a survival of only months. In this study, in vivo growth of xenografted human thyroid carcinomas unexpectedly responded quite differently to neutralizing anti-vascular endothelial growth factor (VEGF) antibody. In particular, lasting inhibition as well as accelerated growth occurred after treatment. Consequently, a panel of anti-angiogenic factors was addressed in a representative sample of thyroid carcinoma lines. VEGF, fibroblast growth factor (FGF-2), and endostatin were demonstrated by Western blotting and EIA, whereas PDGF-A, PDGF-B, and IL-6 were negative. Quantification of VEGF, FGF-2, and endostatin revealed a wide range of concentrations from 500 to 4,200 pg/ml VEGF, 5 to 60 pg/ml FGF-2, and 50 to 300 pg/ml endostatin, not related to a particular histologic thyroid carcinoma background. Angiostatin (kringles 1-3) was detected in all, but one of the cell lines. Finally, aaATIII was confirmed in FTC133 cells. These data highlight the complex regulation of angiogenesis in thyroid carcinoma cell lines and suggest that the array of angiogenic factors differs markedly between individual cell lines. For the first time, angiostatin, endostatin, and possibly also aaATIII are identified as novel candidate regulators of angiogenesis in thyroid carcinoma cells.


Asunto(s)
Inhibidores de la Angiogénesis/farmacología , Carcinoma/metabolismo , Proteínas de Neoplasias/metabolismo , Neovascularización Patológica/metabolismo , Neoplasias de la Tiroides/metabolismo , Inhibidores de la Angiogénesis/uso terapéutico , Carcinoma/tratamiento farmacológico , Línea Celular Tumoral , Relación Dosis-Respuesta a Droga , Evaluación Preclínica de Medicamentos , Humanos , Neovascularización Patológica/tratamiento farmacológico , Neoplasias de la Tiroides/tratamiento farmacológico
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