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1.
Sensors (Basel) ; 21(3)2021 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-33535460

RESUMEN

The preservation of cultural heritage assets of all kind is an important task for modern civilizations. This also includes tools and instruments that have been used in the previous decades and centuries. Along with the industrial revolution 200 years ago, mechanical and electrical technologies emerged, together with optical instruments. In the meantime, it is not only museums who showcase these developments, but also companies, universities, and private institutions. Gyroscopes are fascinating instruments with a history dating back 200 years. When J.G.F. Bohnenberger presented his machine to his students in 1810 at the University of Tuebingen, Germany, nobody could have foreseen that this fascinating development would be used for complex orientation and positioning. At the University of Stuttgart, Germany, a collection of 160 exhibits is available and in transition towards their sustainable future. Here, the systems are digitized in 2D, 2.5D, and 3D and are made available for a worldwide community using open access platforms. The technologies being used are computed tomography, computer vision, endoscopy, and photogrammetry. We present a novel workflow for combining voxel representations and colored point clouds, to create digital twins of the physical objects with 0.1 mm precision. This has not yet been investigated and is therefore pioneering work. Advantages and disadvantages are discussed and suggested work for the near future is outlined in this new and challenging field of tech heritage digitization.

2.
Clin Transplant ; 27(5): E538-45, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-23924205

RESUMEN

BACKGROUND: While previous studies suggest advantages of minimally invasive surgery in living donor nephrectomy, similar data are lacking for kidney transplant recipients. Our aim was to prospectively evaluate short- and long-term outcome for kidney transplant recipients, comparing a short transverse (ST) to a classical hockey-stick (HS) incision. METHODS: Sixty-six patients were randomized into two groups: ST vs. HS from January 2008 to May 2010. ST was defined as incision length ≤9 cm and HS as >14 cm. Perioperative data were collected, with evaluation of intra- and postoperative complications and quality of recovery (QoR) score. RESULTS: There were no significant differences in patient demographics, early or long-term postoperative pain. There were no significant differences in QoR scores between the ST and HS group. Predictive for a worse QoR was persisting incisional pain at the 30-month follow-up. Thirty-days mortality, morbidity, and long-term kidney function did not differ between the two groups (p = 1.00, p = 0.62 and p = 0.66, respectively). CONCLUSIONS: Patient satisfaction as well as graft function and patient mortality was not influenced by incision length. With patient and graft safety being paramount, especially in times of organ shortage, incision length should reflect the requirement for a successful transplantation and not be a measure of feasibility.


Asunto(s)
Fallo Renal Crónico/cirugía , Trasplante de Riñón , Procedimientos Quirúrgicos Mínimamente Invasivos , Complicaciones Posoperatorias , Recuperación de la Función , Femenino , Estudios de Seguimiento , Humanos , Donadores Vivos , Masculino , Persona de Mediana Edad , Estudios Prospectivos , Calidad de Vida , Factores de Tiempo , Resultado del Tratamiento
3.
Carcinogenesis ; 29(2): 363-70, 2008 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-18192686

RESUMEN

The tissue concentrations of the female sex hormone 17beta-estradiol (E2) and its reactive catechol metabolites such as 4-hydroxyestradiol (4-HO-E2) play important roles in hormonal carcinogenesis. They are influenced by the activity of local enzymes involved in the metabolic activation and inactivation of E2. In the mammary gland, catechol estrogens are predominately inactivated by catechol-O-methyltransferase (COMT). Food supplements containing the soy isoflavones genistein and daidzein are consumed because they are believed to protect from breast cancer; however, this proposed benefit is controversial. The aim of the present study was to investigate the influence of soy isoflavones on the gene expression and activity of COMT in cultured human mammary adenocarcinoma MCF-7 cells. Levels of COMT messenger RNA (mRNA) were determined by reverse transcription/competitive polymerase chain reaction and COMT activity was determined by high-performance liquid chromatography analysis of the methylation products of both the model substrate quercetin and the physiological relevant substrate 4-HO-E2. Our study demonstrates for the first time that soy isoflavones at hormonally active concentrations cause a significant reduction of both COMT mRNA levels and COMT activity as well as of the methylation of 4-HO-E2. Experiments using the estrogen receptor (ER) antagonist ICI 182,780 support a role of the ER in the isoflavone-induced down-regulation of COMT expression. Thus, this study not only demonstrates that hormonally active concentrations of soy isoflavones inhibit the detoxification of catechols in this human breast cancer cell line but also implies that diet might influence COMT activity to a greater extent than heretofore recognized.


Asunto(s)
Neoplasias de la Mama/tratamiento farmacológico , Catecol O-Metiltransferasa/metabolismo , Estradiol/análogos & derivados , Regulación Neoplásica de la Expresión Génica , Glycine max/metabolismo , Línea Celular Tumoral , Proliferación Celular , Dieta , Estradiol/metabolismo , Estradiol/farmacología , Estrógenos de Catecol/metabolismo , Femenino , Fulvestrant , Humanos , Modelos Biológicos , Modelos Químicos , Receptores de Estrógenos/metabolismo
4.
Adv Exp Med Biol ; 617: 617-24, 2008.
Artículo en Inglés | MEDLINE | ID: mdl-18497089

RESUMEN

Metabolic activation of 17beta-estradiol (E2) to catechols and quinones together with lack of deactivation constitute risk factors in human breast carcinogenesis. E2-catchols are generated by cytochrome P450-dependent monooxygenases (CYPs). Deactivation of E2, E2-catechols, and E2-quinones is mediated by UDP-glucuronosyltransferase (UGT), sulfotransferase (SULT), catechol-O-methyltransferase (COMT), glutathione-S-transferase (GST), and NADPH-quinone-oxidoreductase (QR) isozymes, respectively. The aim of the present study was to quantify mRNA levels of E2-metabolizing isozymes expressed in MCF-7 cells cultured in the presence/absence of steroids by reverse transcription/competitive PCR in relation to the housekeeping gene hypoxanthine-guanine phosphoribosyltransferase and compare them with expression levels in normal human mammary gland (MG) and liver tissue. CYP1A1, 1B1, SULT1A1, 1A2, membrane-bound and soluble COMT, GSTT1, QR1, and UGT2B7 were detected in both tissues and MCF-7 cells; however, most enzymes were expressed at least tenfold higher in liver. Yet, CYP1B1 was expressed as high in breast as in liver and UGTs were not detected in MCF-7 cells cultured with steroids. MCF-7 cells cultured steroid-free additionally expressed CYP1A2 as well as UGT1A4, 1A8, and 1A9. Normal human liver but not MG expressed CYP1A2, 3A4, UGT1A1, 1A3, 1A4, 1A9, and SULT2A1. UGT1A8 was only detected in MCF7 cells but was not found in human liver. Thus, our study provides a comprehensive overview of expression levels of E2-metabolizing enzymes in a popular in vitro model and in human tissues, which will contribute to the interpretation of in vitro studies concerning the activation/deactivation of E2.


Asunto(s)
Adenocarcinoma/genética , Neoplasias de la Mama/genética , Mama/enzimología , Estradiol/farmacología , Estrógenos/farmacología , Regulación Enzimológica de la Expresión Génica/efectos de los fármacos , Hígado/enzimología , Adenocarcinoma/enzimología , Neoplasias de la Mama/enzimología , Catecol O-Metiltransferasa/genética , Catecol O-Metiltransferasa/metabolismo , Células Cultivadas , Sistema Enzimático del Citocromo P-450/genética , Sistema Enzimático del Citocromo P-450/metabolismo , Estrógenos de Catecol/farmacología , Glucuronosiltransferasa/genética , Glucuronosiltransferasa/metabolismo , Glutatión Transferasa/genética , Glutatión Transferasa/metabolismo , Humanos , ARN Mensajero/genética , ARN Mensajero/metabolismo , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa
5.
Adv Exp Med Biol ; 617: 625-32, 2008.
Artículo en Inglés | MEDLINE | ID: mdl-18497090

RESUMEN

The activation of 17beta-estradiol (E2) to 2-hydroxyestradiol (2-HO-E2), the more genotoxic 4-hydroxyestradiol (4-HO-E2), and the oxidation to the respective quinones constitutes a risk factor in hormonal carcinogenesis. 2-HO-E2 is formed by cytochrome P450 CYP1A1, and 4-HO-E2 is formed by CYP1B1. Both are detoxified by catechol-O-methyltransferase (COMT), whereas their quinones are inactivated by NADPH-quinone-oxidoreductase (QR). Since the soy isoflavones genistein (GEN) and daidzein (DAI) are widely consumed due to their putative protective function in breast carcinogenesis, we examined the influence of E2, GEN, and DAI on CYP1A1/1B1, COMT, and QR expression in MCF-7 cells by reverse transcription/competitive PCR. CYP1A1 and COMT enzyme activity were determined using ethoxyresorufin and quercetin as substrates. Furthermore, estrogen receptor (ER)-regulated cell proliferation was determined by E-screen. E2, GEN, and DAI inhibited the expression of CYP1A1, COMT, and QR. The maximum effect (reduction by 40-80%, depending on the gene product and compound) was obtained at 100 pM E2, 1 microM GEN, and 10 microM DAI, which also induced the most pronounced cell proliferation in the E-screen. In contrast, expression of CYP1B1 was only slightly affected. CYP1A1 and COMT mRNA levels correlated with enzyme activities. The ER antagonist ICI 182,780 reversed the E2- and isoflavone-mediated effects. Thus, GEN and DAI at estrogen-active concentrations stimulate the formation of the more E2 genotoxic metabolites and inhibit the detoxification of catechol and quinone estrogens in estrogen-responsive tumor cells.


Asunto(s)
Neoplasias de la Mama/tratamiento farmacológico , Estradiol/metabolismo , Regulación Enzimológica de la Expresión Génica/efectos de los fármacos , Fitoestrógenos/farmacología , Hidrocarburo de Aril Hidroxilasas/genética , Hidrocarburo de Aril Hidroxilasas/metabolismo , Neoplasias de la Mama/genética , Neoplasias de la Mama/metabolismo , Catecol O-Metiltransferasa/genética , Catecol O-Metiltransferasa/metabolismo , Proliferación Celular/efectos de los fármacos , Citocromo P-450 CYP1A1/genética , Citocromo P-450 CYP1A1/metabolismo , Citocromo P-450 CYP1B1 , Femenino , Regulación Neoplásica de la Expresión Génica , Genisteína/farmacología , Humanos , Isoflavonas/farmacología , NAD(P)H Deshidrogenasa (Quinona)/genética , NAD(P)H Deshidrogenasa (Quinona)/metabolismo , ARN Mensajero/genética , ARN Mensajero/metabolismo , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Células Tumorales Cultivadas
6.
Toxicol Sci ; 100(1): 88-98, 2007 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-17686921

RESUMEN

4-Monochlorobiphenyl (PCB3) is a component of commercial polychlorinated biphenyl (PCB) products and is an airborne environmental pollutant. Our recent study with transgenic Fischer 344 rats revealed the mutagenic potential of PCB3 in the livers of male rats. PCB3 is converted in vitro to hydroxylated metabolites, to hydroquinones (HQs, e.g., 2',5'-HQ and 3',4'-HQ), and can be further oxidized to quinones (Qs, e.g., 2',5'-Q and 3',4'-Q). This raises the question whether the mutagenic potential of PCB3 is due to the mutagenicity of PCB3 itself or of one of the metabolites. In this study, we investigated the mutagenicity of PCB3, of the monohydroxylated metabolites 2'-hydroxy (HO)-, 3'-HO-, and 4'-HO, of the HQs 3',4'-HQ and 2',5'-HQ and of the Qs 3',4'-Q and 2',5'-Q in cultured Chinese hamster V79 cells. The induction of gene mutations was determined at the hypoxanthine-guanine phosphoribosyltransferase (hprt) gene locus by selection with 6-thioguanine. The induction of chromosome and genome mutations was assessed using the micronucleus assay and immunochemical differentiation of micronuclei containing whole chromosomes (kinetochore positive) and DNA fragments (kinetochore negative). The induction of chromosome and genome mutations, detected as micronuclei, was only observed at higher, cytotoxic concentrations of monohydroxylated, catecholic, and quinoid metabolites of PCB3. However, both PCB3-Qs induced a significant increase in the mutant frequency of the hprt gene and did so at submicromolar concentrations. Thus, the present study demonstrates for the first time the mutagenicity of PCB3 metabolites in mammalian cells and identifies quinoid metabolites of PCB3 as potential ultimate mutagens.


Asunto(s)
Compuestos de Bifenilo/toxicidad , Fibroblastos/efectos de los fármacos , Hidroquinonas/toxicidad , Hipoxantina Fosforribosiltransferasa/genética , Micronúcleos con Defecto Cromosómico/inducido químicamente , Mutágenos/toxicidad , Mutación , Quinonas/toxicidad , Animales , Compuestos de Bifenilo/metabolismo , Línea Celular , Proliferación Celular/efectos de los fármacos , Supervivencia Celular/efectos de los fármacos , Cricetinae , Cricetulus , Relación Dosis-Respuesta a Droga , Fibroblastos/patología , Hidroquinonas/metabolismo , Hidroxilación , Masculino , Pruebas de Micronúcleos , Mutágenos/metabolismo , Quinonas/metabolismo , Factores de Tiempo
7.
Mol Nutr Food Res ; 51(7): 888-98, 2007 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-17579897

RESUMEN

Phytosterols are constituents of plant membranes and are thus contained in low concentrations in vegetable products as well as at high concentrations in functional food designed to reduce serum cholesterol levels. Similar to ChOL, phytosterols are oxidized chemically in food and by biotransformation in vivo. Although oxyphytosterols have been detected in the serum of healthy human subjects, little is known of their biological activity. Therefore, the estrogenic and antiestrogenic activities of a mixture of six oxidation products of stigmasterol (oxy-StOL) were determined at the following endpoints: (i) the affinity to isolated human estrogen receptors (ER), (ii) the basal and 17beta-estradiol (E2)-induced expression of the alkaline phosphatase (AlP) in human endometrial adenocarcinoma (Ishikawa) cells, and (iii) the basal and E2-induced proliferation of human breast adenocarcinoma (MCF-7) cells. Oxy-StOL was able to replace E2 from human ERalpha and ERbeta and induced a weak estrogenic response in MCF-7 cells. Moreover, the E2-induced activity of the AlP in Ishikawa cells as well as the E2-induced proliferation of MCF-7 cells were decreased at noncytotoxic concentrations (up to 10 microM), indicating that at least one component of oxy-StOL represents an estrogen-active compound which might interfere with endogenous estrogens.


Asunto(s)
Estradiol/farmacología , Antagonistas de Estrógenos/farmacología , Estigmasterol/química , Estigmasterol/farmacología , Fosfatasa Alcalina/genética , Neoplasias de la Mama , División Celular/efectos de los fármacos , Línea Celular Tumoral , Neoplasias Endometriales , Receptor alfa de Estrógeno/metabolismo , Receptor beta de Estrógeno/metabolismo , Femenino , Expresión Génica/efectos de los fármacos , Humanos , Oxidación-Reducción , ARN Mensajero/análisis , Proteínas Recombinantes/metabolismo
8.
Mol Nutr Food Res ; 50(4-5): 368-72, 2006 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-16534752

RESUMEN

The glycoprotein Wnt-7a participates in a signaling pathway that transmits information among uterine cell types. Disruption of this pathway by the transplacentally acting carcinogen diethylstilbestrol (DES) is associated with morphological abnormalities of the female reproductive tract (FRT). This raises the question whether estrogens in the diet might also interfere with this pathway. Therefore, this study investigated the influence of the steroid hormone 17beta-estradiol (E2), the mycotoxin zearalenone (ZEN), the soy phytoestrogen genistein (GEN), and DES on the expression of Wnt-7a in an endometrial adenocarcinoma cell line (Ishikawa cells) by reverse transcription/competitive PCR. In addition, the enzymatic activity of alkaline phosphatase (ALP) was determined, which is estrogen receptor (ER)-dependently regulated in Ishikawa cells. After treatment of Ishikawa cells with E2, ZEN, GEN, and DES, a decrease in the gene expression of Wnt-7a was observed. Maximum effect (50% reduction) was observed after treatment with concentrations that induced maximum expression of the ALP. Experiments in the presence of the ER antagonist (ICI 182,780) suggested that the ER is involved in the regulation of Wnt-7a in Ishikawa cells. In conclusion, interference with the expression of Wnt genes in the FRT might be a novel mechanism by which estrogens disrupt the function of the FRT.


Asunto(s)
Endometrio/metabolismo , Estrógenos/farmacología , Expresión Génica/efectos de los fármacos , Proteínas Proto-Oncogénicas/genética , Proteínas Wnt/genética , Adenocarcinoma , Fosfatasa Alcalina/metabolismo , Línea Celular Tumoral , Dietilestilbestrol/farmacología , Neoplasias Endometriales , Estradiol/farmacología , Receptor beta de Estrógeno/genética , Femenino , Genisteína/farmacología , Humanos , ARN Mensajero/análisis , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Zearalenona/farmacología
9.
Toxicol Lett ; 164(3): 221-30, 2006 Jul 14.
Artículo en Inglés | MEDLINE | ID: mdl-16464542

RESUMEN

The mycotoxin alternariol (AOH) is an important contaminant of fruit and cereal products. Concern about exposure to low levels of AOH was raised after the disclosure that contamination of food with the AOH-producing species Alternaria alternata is associated with oesophagal cancer. Previously we have reported that AOH induces kinetochore-negative micronuclei in cultured Chinese hamster V79 cells. The present study investigates the mutagenicity of AOH at the hypoxanthine-guanine phosphoribosyltransferase (HPRT) gene locus in V79 cells and at the thymidine kinase (TK) gene locus in mouse lymphoma L5178Y tk(+/-) cells (MLC). Concentrations of 10 microM AOH and more gave rise to a significant and concentration-dependent induction of HPRT and TK mutations in V79 cells and in MLC, respectively. The mutagenic potency of AOH was about 50-fold lower than that of the established mutagen 4-nitroquinoline-N-oxide in both cell lines. Discrimination between small and large colonies in the TK assay revealed the predominant induction of small colonies, which are indicative for extensive chromosomal deletions and which correlated with the induction of micronuclei in MLC. The mutagenicity of AOH may have a bearing on the carcinogenicity of this mycotoxin.


Asunto(s)
Hipoxantina Fosforribosiltransferasa/genética , Lactonas/toxicidad , Mutágenos/toxicidad , Mutación , Micotoxinas/toxicidad , Timidina Quinasa/genética , Animales , Ciclo Celular/efectos de los fármacos , Línea Celular Tumoral , Supervivencia Celular/efectos de los fármacos , Cricetinae , Cricetulus , Relación Dosis-Respuesta a Droga , Fibroblastos/efectos de los fármacos , Masculino , Ratones , Micronúcleos con Defecto Cromosómico/inducido químicamente
10.
Crit Care Med ; 33(3): 547-55, 2005 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-15753746

RESUMEN

OBJECTIVE: To assess long-term survival, health-related quality of life, and associated costs 5 yrs after discharge from a medical intensive care unit. DESIGN: Prospective cohort study. SETTING: Medical intensive care unit of a German university hospital. PATIENTS: Three hundred and three consecutive patients with predominantly cardiovascular and pulmonary disorders admitted between November 1997 and February 1998 with an intensive care unit length of stay >24 hrs. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: Demographic data, Simplified Acute Physiology Score II, Sequential Organ Failure Assessment, simplified Therapeutic Intervention Scoring System, and individual intensive care unit and hospital costs were prospectively recorded. Primary outcomes included 5-yr survival, functional status, health-related quality of life (Medical Outcome Short Form, SF-36), effective costs per survivor, and costs per life year and per quality-adjusted life year gained. Of 303 patients, 44 (14.5%) died in the hospital. Among the remaining 259 patients, 190 (73%) survived the 5-yr follow up and 173 patients (91%) completed the questionnaire. Baseline demographics including gender, age, Simplified Acute Physiology Score II, Sequential Organ Failure Assessment, simplified Therapeutic Intervention Scoring System, and admission diagnosis were similar between hospital and long-term survivors (p > .05 for all). The health status index of those patients surviving the 5-yr follow-up was 0.88, independent of patients' severity of illness. The average effective costs per survivor were 8.827 for intensive care unit costs and 14.130 for intensive care unit and hospital costs. Mean costs per life year and per quality-adjusted life year gained amounted to 19.330 and 21.922 , respectively. Increasing severity of illness was associated with higher costs. CONCLUSIONS: Considering the severity of illness and the patients' outcome, the costs associated with both life year and quality-adjusted life year gained were within generally accepted limits for other potentially life-saving treatments.


Asunto(s)
Enfermedad Crítica/economía , Costos de la Atención en Salud , Estado de Salud , Unidades de Cuidados Intensivos/economía , Calidad de Vida , APACHE , Análisis Costo-Beneficio , Enfermedad Crítica/mortalidad , Femenino , Alemania/epidemiología , Humanos , Masculino , Persona de Mediana Edad , Estudios Prospectivos , Años de Vida Ajustados por Calidad de Vida , Asignación de Recursos , Estadísticas no Paramétricas , Tasa de Supervivencia
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