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1.
J Infect Chemother ; 25(4): 298-301, 2019 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-30482700

RESUMEN

Raoultella planticola is a gram-negative, encapsulated, aerobic bacterium within the Enterobacteriaceae family. It has been primarily described as pathogen in cases with pneumonia and gastrointestinal infections. Here we describe a case of severe pelvic cellulitis in a patient with neutropenia following induction therapy for myeloid sarcoma. The patient experienced a septic shock and was treated successfully with antibiotic therapy. A literature review is provided to put this case in context with previous reports on R. planticola. This report highlights that awareness for uncommon pathogens is crucial in the clinical management of infections in neutropenic patients.


Asunto(s)
Antibacterianos/uso terapéutico , Protocolos de Quimioterapia Combinada Antineoplásica/efectos adversos , Celulitis (Flemón)/microbiología , Neutropenia Febril Inducida por Quimioterapia/complicaciones , Infecciones por Enterobacteriaceae/microbiología , Enterobacteriaceae/aislamiento & purificación , Adulto , Celulitis (Flemón)/complicaciones , Celulitis (Flemón)/diagnóstico , Celulitis (Flemón)/tratamiento farmacológico , Neutropenia Febril Inducida por Quimioterapia/diagnóstico , Neutropenia Febril Inducida por Quimioterapia/etiología , Infecciones por Enterobacteriaceae/complicaciones , Infecciones por Enterobacteriaceae/diagnóstico , Infecciones por Enterobacteriaceae/tratamiento farmacológico , Humanos , Imagen por Resonancia Magnética , Masculino , Pelvis/diagnóstico por imagen , Sarcoma Mieloide/tratamiento farmacológico , Resultado del Tratamiento
2.
World J Urol ; 31(4): 855-9, 2013 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-22037634

RESUMEN

OBJECTIVE: To date, only few studies have evaluated the impact of ureteral stenting prior to ureterorenoscopy. This study is to clarify the role of preoperative ureteral stenting in the treatment for ureteral stones. METHODS: We retrospectively reviewed 550 ureterorenoscopies from 1998 to 2008. Patients were classified into two groups depending on whether they had a stent placed before URS. Baseline characteristics of patients and stone properties, stone-free rates, complications, and operation times were compared between both groups. Subanalysis was performed regarding stone localization. We retrospectively reviewed data from patient documentation, X-ray imagery, intravenous urography, and operation reports. RESULTS: Baseline characteristics of patients were similar in both groups. The majority of patients underwent stent placement before the ureteroscopic stone treatment (88.4%). The mean operation time in the prestented group was longer (43.3 vs. 38.4 min). Stone-free rate of patients with stent was 72.2%, compared to 59.4% without preoperative stenting. The rate of minor complications was 4.7% with stent versus 9.4% without stent, major complications 0.6% versus 1.6%, respectively. Patients with distal ureter stones had similar stone-free rates regardless of a stent placement (90.1% with stent vs. 87.6% without), and no difference in complication rates was observed (3.5% with stent vs. 3.1% without), respectively. CONCLUSIONS: Stent placement prior to ureteroscopic stone treatment in distal ureter is not reasonable and does not considerably improve stone-free rates.


Asunto(s)
Stents , Cálculos Ureterales/cirugía , Ureteroscopía , Femenino , Humanos , Incidencia , Masculino , Persona de Mediana Edad , Tempo Operativo , Complicaciones Posoperatorias/epidemiología , Periodo Preoperatorio , Estudios Retrospectivos , Resultado del Tratamiento , Ureteroscopía/efectos adversos
3.
Aktuelle Urol ; 51(6): 582-592, 2020 Dec.
Artículo en Alemán | MEDLINE | ID: mdl-29370587

RESUMEN

A recently discovered mechanism enabling prostate cancer cells to escape the effects of endocrine therapies consists in the synthesis of C-terminally truncated, constitutively active androgen receptor (AR) splice variants (AR-V). Devoid of a functional C-terminal hormone/ligand binding domain, various AR-Vs are insensitive to therapies targeting the androgen/AR signalling axis. Preliminary studies suggest that AR-V7, the most common AR-V, is a promising predictive tumour marker and a relevant selection marker for the treatment of advanced prostate cancer. This review critically outlines recent advances in AR-V7 diagnostics and presents an overview of current AR-V7 targeted therapies.


Asunto(s)
Neoplasias de la Próstata , Receptores Androgénicos , Humanos , Masculino , Mutación , Pronóstico , Neoplasias de la Próstata/diagnóstico , Neoplasias de la Próstata/genética , Neoplasias de la Próstata/terapia , Sitios de Empalme de ARN , Receptores Androgénicos/genética , Transducción de Señal
4.
Urologe A ; 46(9): 1271-4, 2007 Sep.
Artículo en Alemán | MEDLINE | ID: mdl-17641866

RESUMEN

Prostate cancer is more frequently diagnosed in men from Western countries than from Asian societies. Therefore, nutritional factors such as phyto-oestrogens from soya are considered to cause this prostate cancer prevention effect. As there is no curative therapy for hormone-refractory prostate cancer, new strategies are in demand which might include phyto-oestrogens or inhibitors of histone deacetylases. Both approaches have in common the potential to reduce the aberrant androgen receptor and IGF receptor signalling. Furthermore, invasiveness and acquired survival strategies of tumours can be diminished. Reduced tumour cell proliferation and PSA secretion coincide with altered gene expression in the aforementioned processes. In addition, selective knock-down of genes by RNA interference afforded functional analyses regarding impact and succession of expression events involved in the beneficial effects caused by phyto-oestrogens and histone deacetylase inhibitors.


Asunto(s)
Terapias Complementarias , Inhibidores de Histona Desacetilasas , Fitoestrógenos/uso terapéutico , Fitoterapia , Neoplasias de la Próstata/genética , Neoplasias de la Próstata/terapia , Biomarcadores de Tumor/genética , División Celular/efectos de los fármacos , División Celular/genética , Expresión Génica/efectos de los fármacos , Humanos , Masculino , ARN Interferente Pequeño/genética , Receptores Androgénicos/efectos de los fármacos , Receptores Androgénicos/genética , Transducción de Señal/efectos de los fármacos , Transducción de Señal/genética
5.
Urologe A ; 56(4): 465-471, 2017 Apr.
Artículo en Alemán | MEDLINE | ID: mdl-28246761

RESUMEN

Androgen deprivation is still standard therapy for prostate cancer, either as primary androgen deprivation therapy or with the use of secondary hormonal drugs including abiraterone and enzalutamide. However, especially the clinically occult side effects like metabolic changes or cardiovascular complications and effects on the psyche of the patient are often not recognized in daily practice. Active monitoring of such side effects is essential for prevention and early intervention. In addition, the efficacy of androgen deprivation therapies is limited by primary and secondary resistance. The underlying molecular mechanism including splice variants of the androgen receptor in contrast to mutations are usually reversible and should be regarded as a sign of efficacy of the current treatment. Therefore, the clever, timely use of androgen deprivation or even the use of a bipolar androgen therapy should enable reversal of resistance to again render tumor cells sensitive to androgen-deprivation therapy.


Asunto(s)
Antagonistas de Andrógenos/administración & dosificación , Antagonistas de Andrógenos/efectos adversos , Enfermedades Cardiovasculares/inducido químicamente , Enfermedades Metabólicas/inducido químicamente , Neoplasias de la Próstata/complicaciones , Neoplasias de la Próstata/tratamiento farmacológico , Enfermedades Cardiovasculares/prevención & control , Relación Dosis-Respuesta a Droga , Interacciones Farmacológicas , Resistencia a Antineoplásicos , Medicina Basada en la Evidencia , Humanos , Masculino , Enfermedades Metabólicas/prevención & control , Neoplasias de la Próstata Resistentes a la Castración , Resultado del Tratamiento
6.
Urologe A ; 56(9): 1164-1167, 2017 Sep.
Artículo en Alemán | MEDLINE | ID: mdl-28702748

RESUMEN

Androgen receptor splice variants (AR-Vs), if overexpressed, lack the ligand-binding domain conveying metastasized castration-resistant prostate cancer with a therapeutic resistance to androgen receptor signaling inhibitors. Particularly AR-V7 has recently been proposed as a potential predictive biomarker to identify patients who would probably benefit most from taxane-based cytotoxic treatment. Several assays to substantiate or quantify AR-V7 expression have recently been proposed. However, their broad clinical value is still debatable. This contemporary update aims to shed light on the current evidence in the field and draw distinct practical conclusions.


Asunto(s)
Biomarcadores de Tumor/genética , Marcadores Genéticos/genética , Neoplasias de la Próstata Resistentes a la Castración/genética , Isoformas de Proteínas/genética , Receptores Androgénicos/genética , Andrógenos/uso terapéutico , Androstenos/uso terapéutico , Benzamidas , Humanos , Masculino , Nitrilos , Feniltiohidantoína/análogos & derivados , Feniltiohidantoína/uso terapéutico , Neoplasias de la Próstata Resistentes a la Castración/diagnóstico , Neoplasias de la Próstata Resistentes a la Castración/tratamiento farmacológico , ARN Mensajero/genética , Taxoides/uso terapéutico , Testosterona/sangre
7.
Orthop Traumatol Surg Res ; 103(2): 209-215, 2017 04.
Artículo en Inglés | MEDLINE | ID: mdl-28025151

RESUMEN

BACKGROUND: Three-dimensional (3D) acetabular orientation is a fundamental topic in orthopedic surgery. Computed tomography (CT) allows 3D measurement of native acetabular orientation, but with a substantial radiation dose. The EOS imaging system was developed to perform this kind of evaluation, but has not been validated in this indication with specific attention to the acetabulum. We therefore performed a prospective study using EOS to assess: (1) the reproducibility of the 3D acetabulum orientation measures; (2) normative asymptomatic acetabular morphology in standing position, according to side and gender; and (3) the relationship between acetabular anteversion and pelvic incidence. HYPOTHESIS: The low-dose EOS imaging system is a reproducible method for measuring 3D acetabular orientation in standing position. PATIENTS AND METHODS: In a previous prospective study of spine sagittal balance, 165 asymptomatic volunteers were examined on whole-body EOS biplanar X-ray; 102 had appropriate images for pelvic and acetabular analysis, with an equal sex-ratio (53 female, 49 male). These EOS images were reviewed using sterEOS 3D software, allowing automatic measurement of acetabular parameters (anteversion and inclination) and pelvic parameters (pelvic incidence, pelvic tilt and sacral slope) in an anatomical (anterior pelvic plane: APP) and a functional reference plane (patient vertical plane: PVP). RESULTS: Both intra- and inter-observer analysis showed good agreement (ICC>0.90); Bland-Altman plot distributions were good. Acetabular anatomical anteversion and inclination relative to APP (AAAPP and AIAPP, respectively) were significantly greater in women than in men, with no effect of side (right AAA: women 21.3°±3.4° vs. men 16.1°±3.3° (P<0001); right AIAPP: women 55.3°±3.7° vs. men 52.5°±3.0° (P<0001); left AAAPP: women 20.9°±3.5° vs. men 15.6°±4.0° (P<0001); left AIAPP: women 54.6°±3.5° vs. men 52.7°±2.8° (P=0003)). The same differences between men and women were observed when measurements were related to PVP. Pelvic incidence subgroup (<44°; 44-62°; >62°) correlated significantly with functional acetabular orientation in standing position: PVP functional anteversion decreased by 5° relative to APP anteversion with incidence <44°, was equal to APP with incidence 44-62°, and or was greater by 4° relative to APP with incidence >62°. DISCUSSION: The use of a 3D sterEOS software prototype version for 3D reconstruction of the native acetabulum from standard EOS X-ray was shown to be a reliable and reproducible method. This innovative method enabled the reference values of 3D acetabular orientation in standing position to be measured for the first time. The results reinforced the concept of hip-spine relationships, and involved very low radiation dose. LEVEL OF EVIDENCE: IV prospective study without control group.


Asunto(s)
Acetábulo/diagnóstico por imagen , Imagenología Tridimensional/métodos , Postura , Tomografía Computarizada por Rayos X/métodos , Acetábulo/anatomía & histología , Adulto , Femenino , Humanos , Masculino , Tamaño de los Órganos , Pelvis , Estudios Prospectivos , Reproducibilidad de los Resultados , Factores Sexuales , Adulto Joven
8.
Urologe A ; 45(2): 195-6, 197-201, 2006 Feb.
Artículo en Alemán | MEDLINE | ID: mdl-16237540

RESUMEN

INTRODUCTION: Phytoestrogenes are plant-derived compounds that have been shown to exert an antiproliferative potential on prostate cancer cells, although the exact mechanisms are still unclear. In prostate cancer cells proliferation is regulated by modulation of the IGF-1 receptor (IGF-R-1) by the androgen receptor (AR) and its co-activator prostate derived Ets factor (PDEF). Phytooestrogenes interact with these mechanisms as demonstrated exemplarily in the presented study with the isoflavone tectorigenin derived from Belamcanda chinensis. MATERIAL AND METHODS: Cultured androgen-sensitive LNCaP prostate cancer cells were treated with tectorigenin of 100 microM for 24 hours. The mRNA-expression of AR, PSA, PDEF, hTERT, TIMP-3 and IGF-R-1 were quantified by real-time RT-PCR. Furthermore, the expression or activity of PSA, telomerase and IGF-R-1 was measured on the protein level. In addition, we investigated in nude mice the influence of a diet of extracts of Belamcanda chinensis on the growth of subcutaneously injected LNCaP cells versus a control group of animals fed with a soy-free diet. RESULTS: In cultured LNCaP cells treatment with tectorigenin resulted in a significant down-regulation of the gene expression of AR, PDEF, PSA, IGF-R-1 and hTERT. On the protein level PSA secretion and the activity of telomerase and IGF-R-1 expression was also decreased. The gene expression of TIMP-3 was distinctly up-regulated by tectorigenin. Nude mice fed with Belamcanda chinensis extract showed a significantly decreased incidence and tumor growth compared to controls. CONCLUSIONS: Tectorigenin shows an inhibition of the IGF-1-R modulated cell proliferation of PCa-Cells, due to modulation of the activity the co-activator PDEF independently from the AR. Furthermore, tectorigenin has pro-apoptotic effects and decreases tissue invasion by up-regulation of TIMP-3. Therefore, phytooestrogenes are an interesting option in the therapy of prostate especially advanced prostate cancer.


Asunto(s)
Biomarcadores de Tumor/metabolismo , Isoflavonas/administración & dosificación , Proteínas de Neoplasias/metabolismo , Fitoestrógenos/administración & dosificación , Extractos Vegetales/administración & dosificación , Neoplasias de la Próstata/tratamiento farmacológico , Neoplasias de la Próstata/metabolismo , Animales , Antineoplásicos/administración & dosificación , Línea Celular Tumoral , Supervivencia Celular/efectos de los fármacos , Estudios de Factibilidad , Humanos , Masculino , Ratones , Ratones Desnudos , Fitoterapia/métodos , Neoplasias de la Próstata/patología , Resultado del Tratamiento
9.
Aktuelle Urol ; 47(1): 79-85, 2016 Feb.
Artículo en Alemán | MEDLINE | ID: mdl-26814975

RESUMEN

With the development of Abiraterone and Enzalutamide new treatment option have become available in addition to Docetaxel for first-line treatment of castration resistant prostate cancer. However, resistance and ultimately failure occurs inevitably with all available treatment options. Moreover, cross-resistance leads to considerably reduced efficacy in second-line treatment. Preclinical data suggest discriminative mechanisms of resistance development for Abiraterone and Enzalutamide. Clinical confirmation of these putative mechanisms for treatment failure might facilitate recommendations for future sequencing of these drugs.


Asunto(s)
Antineoplásicos/efectos adversos , Antineoplásicos/uso terapéutico , Resistencia a Medicamentos , Feniltiohidantoína/análogos & derivados , Neoplasias de la Próstata/tratamiento farmacológico , Acetato de Abiraterona/efectos adversos , Acetato de Abiraterona/uso terapéutico , Benzamidas , Humanos , Masculino , Nitrilos , Feniltiohidantoína/efectos adversos , Feniltiohidantoína/uso terapéutico
10.
Biochim Biophys Acta ; 944(2): 285-96, 1988 Oct 06.
Artículo en Inglés | MEDLINE | ID: mdl-3052588

RESUMEN

Human erythrocytes treated with low concentrations (1-5 mM) of the carboxyl group-modifying reagent 1-ethyl-3-(3-dimethylaminopropyl)carbodiimide (EDC) lose their native deformability in parallel with extensive cross-linking of the membrane skeleton. After treatment with higher (5-40 mM) concentrations of the reagent the cells develop a hitherto undescribed property: when subjected to even very low shear stresses (resuspension after packing by centrifugation or viscometric shearing at up to 4 s-1) they become highly leaky to ions, lose their K+ with a half-time of about 5 min and subsequently undergo hemolysis. Lysis is not accompanied by cell fragmentation as occurs with mechanical hemolysis, but is colloid-osmotic, due to the formation of aqueous membrane leaks with an apparent radius of about 3 nm. Leakiness and lysis affect an increasing fraction of the cell population, in relation to (a) the concentration of EDC applied, (b) the shearing intensity, and (c) particularly, the hematocrit during shearing. The physical parameter determining the mechanical component of this 'chemo-mechanical' leak formation is not predominantly the shear stress. Rather, cell-cell interactions of as yet undefined nature seem to be involved. The analysis of chemo-mechanical leak formation may provide interesting insights into the influence of mechanical forces on membranes.


Asunto(s)
Carbodiimidas/farmacología , Membrana Eritrocítica/efectos de los fármacos , Etildimetilaminopropil Carbodiimida/farmacología , Viscosidad Sanguínea , Permeabilidad de la Membrana Celular , Membrana Eritrocítica/lesiones , Hemólisis , Humanos , Microscopía de Contraste de Fase , Modelos Biológicos , Potasio/sangre , Solubilidad , Estrés Mecánico , Factores de Tiempo , Agua
11.
Biochim Biophys Acta ; 944(2): 297-307, 1988 Oct 06.
Artículo en Inglés | MEDLINE | ID: mdl-3179292

RESUMEN

The chemical reactions underlying the chemo-mechanical leak formation in human erythrocytes upon treatment with the carboxyl-modifying reagent 1-ethyl-3-(3-dimethylaminopropyl)carbodiimide (EDC) and subsequent minimal shearing, described in the preceding paper (Thelen, P. and Deuticke, B. (1988) Biochim. Biophys. Acta 944, 285-296), are here characterized in more detail. The capacity to form leaks under minimal shearing results from the transformation of certain membrane carboxyl groups into an activated state, i.e., the O-acylisourea derivative of the original COO- group. This activated state re-disappears, i.e., the cell become shear-resistant again, when the O-acylisourea derivative under goes spontaneous hydrolysis upon removal of excess EDC in the suspension by addition of a cation-exchange resin. The activated state can be stabilized by addition of N-hydroxysuccinimide or N-hydroxysulfosuccinimide, which both form activated esters. The additional presence of nucleophilic amines, e.g., glycine methyl ester or aminomethane sulfonate, during the pretreatment with EDC strongly suppresses leak formation during subsequent shearing, which substantiates the involvement of COO- groups. EDC reactive side groups other than COO- (e.g., tyrosyl-OH or sulfhydryls) can be discarded as candidates for the underlying chemical reaction. The formation of the chemo-mechanical leaks most likely results from the cross-linking between a subpopulation of activated carboxyl groups and endogenous amino groups. This cross-linking, however, seems only to occur when the two reacting groups are brought into contact by the shear-induced cell--cell interactions required for leak formation. Besides information on chemo-mechanical leak formation the study provides new data helpful for future work with carbodiimides.


Asunto(s)
Carbodiimidas/farmacología , Membrana Eritrocítica/efectos de los fármacos , Etildimetilaminopropil Carbodiimida/farmacología , Membrana Eritrocítica/lesiones , Glutatión/metabolismo , Humanos , Concentración de Iones de Hidrógeno , Fragilidad Osmótica , Potasio/metabolismo , Estrés Mecánico , Relación Estructura-Actividad , Succinimidas/farmacología , Factores de Tiempo
12.
EJNMMI Res ; 5(1): 66, 2015 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-26576996

RESUMEN

BACKGROUND: Prostate-specific membrane antigen (PSMA) is a promising target for diagnostics and therapy of prostate carcinoma (PCa). Based on the hypothesis that PSMA expression can be modulated by variations in androgen deprivation therapy (ADT), we investigated the binding of a PSMA-directed radiopharmaceutical in vitro in order to get an insight of the interactions between altered premedication and PSMA expression before repetitive PSMA-directed PET/CT for therapy response and targeted therapy implementation. METHODS: The human castration-resistant PCa cell line VCaP (CRPC) was treated with either 1 nmol/L testosterone (T) over 20 passages yielding the androgen-sensitive cell line (revCRPC) or with 5 µmol/L abiraterone acetate (AA) generating the abiraterone-tolerant subtype CRPCAA. In these cell lines, T and AA were varied by either supply or withdrawal of T and AA. PSMA expression of the three cell culture models was detected by Western blot and immunohistochemical staining. For quantitative measurement of tracer uptake, 0.3 nmol/L (68)Ga-labelled PSMA-HBED-CC peptide (100-300 kBq/ml) was added to different treated parallel cultures (n = 9 each). Time-dependent uptake per 10(6) cells of each culture was calculated and evaluated. PSMA mRNA expression was investigated by qPCR. RESULTS: PSMA expression increased dependently on intensified ADT in all three basic cell lines. (68)Ga-PSMA-HBED-CC uptake almost doubled during 3 h in all cell lines (p < 0.01). Compared to the basic cells, pre-incubation with abiraterone for 48 h resulted in a significant increased uptake in CRPC (p < 0.001). In revCRPC, 48-h AA pre-incubation resulted in an eightfold higher uptake after 3 h (p < 0.001). Additional withdrawal of external testosterone increased the uptake up to tenfold (p < 0.01). The increase of PSMA expression upon ADT and AA treatments was confirmed by qPCR and Western blot data. Furthermore, in CRPCAA, 48-h AA withdrawal increased the uptake up to fivefold (p < 0.01). CONCLUSIONS: The investigated three PCa cell culture subtypes represent a serial preclinical model of androgen deprivation therapy as a proxy for clinical situations with differing basal PSMA expression. The uptake of PSMA-binding tracers could be stimulated by therapeutic effective short-term variation in premedication in all stages of ADT response. These complex interactions have to be considered in the interpretation of diagnostic imaging using PSMA ligands as well as in the optimal timing of PSMA-based therapies.

13.
Int J Oncol ; 19(2): 367-71, 2001 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-11445853

RESUMEN

Nephroblastomas (Wilms' tumors) are curable with survival rates above 80%. Some tumors, however, fail to respond to therapy and those patients have a poor prognosis. In a search for prognostic markers, we investigated the expression of the multidrug resistance-related protein 1 (MRP1) in 32 nephroblastomas by means of immunohistochemistry. The immunohistochemical results were validated with a real-time RT-PCR technique. MRP1 expression was heterogeneous and predominantly found in the blastemal and epithelial compartments compared to the stromal elements of nephroblastomas. We found significant relationships of MRP1 expression to survival of patients and to expression of p53, HSP70, and LRP/MVP. The relationship between MRP1 and p53 expression is a clue that the transcriptional control of MRP1 by p53 reported for other tumor types may also take place in nephroblastomas. The correlation of MRP1 to other drug resistance genes, e.g. HSP70 and LRP/MVP in nephroblastomas indicates that the co-expression of different drug resistance genes may be under a common regulation of still unknown transcription factors.


Asunto(s)
Transportadoras de Casetes de Unión a ATP/genética , Neoplasias Renales/patología , Tumor de Wilms/patología , Transportadoras de Casetes de Unión a ATP/análisis , Resistencia a Múltiples Medicamentos , Regulación Neoplásica de la Expresión Génica , Proteínas HSP70 de Choque Térmico/análisis , Humanos , Inmunohistoquímica , Neoplasias Renales/genética , Neoplasias Renales/metabolismo , Proteínas Asociadas a Resistencia a Múltiples Medicamentos , Proteínas de Neoplasias/análisis , Estadificación de Neoplasias , ARN Mensajero/genética , ARN Mensajero/metabolismo , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Análisis de Supervivencia , Proteína p53 Supresora de Tumor/análisis , Partículas Ribonucleoproteicas en Bóveda , Tumor de Wilms/genética , Tumor de Wilms/metabolismo
14.
Int J Oncol ; 19(1): 163-8, 2001 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-11408938

RESUMEN

Nephroblastomas (Wilms' tumors) are curable with survival rates above 80%. Some tumors, however, fail to respond to therapy and those patients have a poor prognosis. In a search for molecular markers of drug resistance, we investigated the expression of lung resistance protein (LRP) in tissue samples from 32 children with nephroblastoma by means of immunohistochemistry. LRP is a human major vault protein (MVP) and is associated with multidrug resistance of tumors. LRP/MVP expression was found in the blastemal and epithelial compartments but to a significantly lesser extent in the stromal compartment of Wilms' tumors. Expression was generally heterogeneous with respect to staining intensity and percentage of positive cells. We found significant relationships between LRP/MVP expression and chemotherapeutic pre-treatment of tumors and tumor stage. The immunohistochemical results were validated with a real-time RT-PCR technique and a significant association between protein and mRNA expression was observed.


Asunto(s)
Biomarcadores de Tumor/metabolismo , Neoplasias Renales/metabolismo , Proteínas de Neoplasias/metabolismo , Partículas Ribonucleoproteicas en Bóveda/metabolismo , Tumor de Wilms/metabolismo , Antibióticos Antineoplásicos/uso terapéutico , Antineoplásicos Fitogénicos/uso terapéutico , Biomarcadores de Tumor/genética , Niño , Preescolar , Cartilla de ADN/química , Dactinomicina/uso terapéutico , Resistencia a Múltiples Medicamentos , Humanos , Técnicas para Inmunoenzimas , Neoplasias Renales/tratamiento farmacológico , Neoplasias Renales/patología , Proteínas de Neoplasias/genética , ARN Mensajero/metabolismo , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Partículas Ribonucleoproteicas en Bóveda/genética , Vincristina/uso terapéutico , Tumor de Wilms/tratamiento farmacológico , Tumor de Wilms/patología , Microglobulina beta-2/metabolismo
15.
J Biochem ; 116(2): 285-90, 1994 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-7822245

RESUMEN

We isolated a mutant of Escherichia coli which was defective in an Na+/H+ antiporter and grew poorly under alkaline conditions [Ishikawa, T., Hama, H., Tsuda, T., and Tsuchiya, T. (1987) J. Biol. Chem. 262, 7443-7446]. Later, it was concluded that the defective Na+/H+ antiporter in the mutant was the NhaB system, and the nhaB gene was mapped to 25.6 min on the E. coli chromosome [Thelen, P., Tsuchiya, T., and Goldberg, E.B. (1991) J. Bacteriol. 173, 6553-6557]. We found that the NhaB-defective cells cannot grow in a high pH medium. Furthermore, intracellular pH in the mutant cells was almost the same as extracellular pH between 7.9 and 9.1, that is, intracellular pH was not regulated at this pH range. On the other hand, intracellular pH of the wild-type cells was maintained at about 7.6 when the extracellular pH was between 7.6 and 8.5. Thus, the NhaB Na+/H+ antiporter is essential for the regulation of intracellular pH under alkaline conditions in E. coli. Introduction of nhaA gene into the mutant cells increased Na+/H+ antiporter activity, but did not restore the defective growth and defective intracellular pH regulation under alkaline conditions.


Asunto(s)
Proteínas Bacterianas/fisiología , Escherichia coli/fisiología , Intercambiadores de Sodio-Hidrógeno/fisiología , Proteínas Bacterianas/genética , Escherichia coli/genética , Escherichia coli/crecimiento & desarrollo , Concentración de Iones de Hidrógeno , Líquido Intracelular/metabolismo , Mutación , Intercambiadores de Sodio-Hidrógeno/genética
16.
Virchows Arch ; 439(5): 645-52, 2001 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-11764385

RESUMEN

Rapidly growing tumors often develop necrosis. In the present study the expression of vascular endothelial growth factor (VEGF) was investigated and compared to microvessel density and necrosis of renal cell carcinomas. In the tumor-host interface the microvessel density was significantly increased compared to central tumor areas. Tumor necrosis was associated with a decrease of microvessel density and an increase of the VEGF protein expression within the perinecrotic rim. VEGF protein was focally upregulated in vital tumor tissue. An increase of the apoptotic rate of endothelia and vital tumor tissue in tumors with necrosis could not be detected. VEGF(121,165) mRNA was decreased in proliferatively active carcinomas compared to less proliferative tumors. Multicellular renal cell cancer spheroids as a model of chronic hypoxia developed central apoptosis but no necrosis. VEGF was upregulated in the spheroid. Tumor microvessels expressed matrix metalloproteinase -2 and -9 and an incomplete pericyte covering in comparison to tumor-free tissue indicating immature active angiogenesis. We conclude that highly proliferative renal cell carcinomas outgrow their vascular supply and develop chronic hypoxia inducing a decrease of proliferation and an increase of VEGF expression. However, chronic hypoxia does not cause significant necrosis or apoptosis. Tumor necrosis is more likely induced by acute hypoxia due to immature microvessels. Furthermore, VEGF expression associated with concomitant tumor necrosis may help identify renal cell carcinomas susceptible to antiangiogenic therapy.


Asunto(s)
Carcinoma de Células Renales/metabolismo , Factores de Crecimiento Endotelial/biosíntesis , Neoplasias Renales/metabolismo , Linfocinas/biosíntesis , Neovascularización Patológica/metabolismo , Antígenos Nucleares , Apoptosis , Carcinoma de Células Renales/irrigación sanguínea , Carcinoma de Células Renales/patología , División Celular , Factores de Crecimiento Endotelial/genética , Endotelio Vascular/metabolismo , Endotelio Vascular/patología , Humanos , Inmunohistoquímica , Hibridación in Situ , Etiquetado Corte-Fin in Situ , Neoplasias Renales/irrigación sanguínea , Neoplasias Renales/patología , Linfocinas/genética , Metaloproteinasa 2 de la Matriz/biosíntesis , Metaloproteinasa 2 de la Matriz/genética , Metaloproteinasa 9 de la Matriz/biosíntesis , Metaloproteinasa 9 de la Matriz/genética , Microcirculación , Necrosis , Proteínas Nucleares/análisis , Pericitos/metabolismo , Pericitos/patología , Molécula-1 de Adhesión Celular Endotelial de Plaqueta/análisis , ARN Mensajero/análisis , ARN Neoplásico/análisis , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Esferoides Celulares/metabolismo , Esferoides Celulares/patología , Células Tumorales Cultivadas , Factor A de Crecimiento Endotelial Vascular , Factores de Crecimiento Endotelial Vascular
17.
J Med Microbiol ; 11(4): 463-70, 1978 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-722783

RESUMEN

Culture filtrates of micro-organisms isolated from the upper intestinal secretions of malnourished children and grown in pure culture were shown to impair the intestinal absorption of water and electrolytes in live rats. Decreased net movement out of the intestinal lumen, or actual secretion of water, sodium or potassium into the intestinal lumen, was found with culture filtrates of single isolates of Staphylococcus epidermidis, Escherichia coli 055, Escherichia coli B7A, Shigella sonnei, Klebsiella pneumoniae, Candida albicans and Candida tropicalis. These organisms have been found to contaminate upper intestinal secretions in malnourished children and it is suggested that the effects observed in these experiments might be relevant to the production of the diarrhoea that is a dominant clinical feature of childhood malnutrition.


Asunto(s)
Toxinas Bacterianas/toxicidad , Enterotoxinas/toxicidad , Absorción Intestinal/efectos de los fármacos , Yeyuno/metabolismo , Micotoxinas/toxicidad , Potasio/metabolismo , Sodio/metabolismo , Agua/metabolismo , Animales , Bacterias/metabolismo , Candida/metabolismo , Niño , Enterotoxinas/biosíntesis , Humanos , Secreciones Intestinales/microbiología , Masculino , Trastornos Nutricionales/microbiología , Ratas , Especificidad de la Especie
18.
Anticancer Res ; 19(2C): 1563-5, 1999.
Artículo en Inglés | MEDLINE | ID: mdl-10365146

RESUMEN

The field of angiogenesis and its mediators in tumour tissue is gaining more and more interest because of their therapeutic implications to arrest progressive growth and metastasis. We examined the expression status of the proangiogenic vascular endothelial growth factor (VEGF) in tumour tissue and adjacent tumour-free tissue from renal cell carcinoma (RCC) as well as in cell cultures deriving from tumour tissue. Quantification of both secreted isoforms ot VEGF by competitive RT-PCR revealed a marked increase of VEGF message in tumours and especially in cell cultures from RCC. We found a significant correlation of VEGF expression and microvessel density which was investigated immunohistochemically. As further compared to other urological neoplasms we investigated for VEGF mediated vascularization, RCC is the most promising candidate for anti-angiogenic therapies.


Asunto(s)
Carcinoma de Células Renales/genética , Factores de Crecimiento Endotelial/genética , Neoplasias Renales/genética , Linfocinas/genética , Transcripción Genética , Carcinoma de Células Renales/irrigación sanguínea , Carcinoma de Células Renales/patología , Carcinoma de Células Renales/cirugía , Regulación Neoplásica de la Expresión Génica , Humanos , Riñón/citología , Riñón/metabolismo , Riñón/patología , Neoplasias Renales/irrigación sanguínea , Neoplasias Renales/patología , Neoplasias Renales/cirugía , Microcirculación/patología , Estadificación de Neoplasias , Nefrectomía , ARN Mensajero/análisis , ARN Mensajero/genética , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa/métodos , Células Tumorales Cultivadas , Factor A de Crecimiento Endotelial Vascular , Factores de Crecimiento Endotelial Vascular
19.
Anticancer Res ; 21(4B): 2915-20, 2001.
Artículo en Inglés | MEDLINE | ID: mdl-11712786

RESUMEN

Nephroblastomas (Wilms' tumors) are curable with survival rates above 80%. Nevertheless, some tumors fail to respond to therapy and those patients have a poor prognosis. Prognostic factors for nephroblastomas have still not been satisfactorily explored. In an effort to unravel molecular markers for non-responding nephroblastomas, we investigated by means of immunohistochemistty the expression of heat-shock protein 70 (HSP70) in formalin-fixed and paraffin-embedded tissue samples from 32 children afflicted with nephroblastoma. The results were validated using real-time RT-PCR. HSP70 expression was confined to blastemal and epithelial components, while the tumor stroma was negative. HSP70 expression was greater, if the tumors had been chemotherapeutically treated prior to operation, indicating that cytostatic drugs induce HSP70. Furthermore, high HSP70 expression was confined to tumors from children who survived, whereas tumors from dead patients were negative or weakly-positive for HSP70. Though the number of cases analyzed was small, they provide an indication that HSP70 expression may be of prognostic value.


Asunto(s)
Biomarcadores de Tumor/análisis , Regulación Neoplásica de la Expresión Génica , Proteínas HSP70 de Choque Térmico/biosíntesis , Neoplasias Renales/metabolismo , Proteínas de Neoplasias/biosíntesis , Tumor de Wilms/metabolismo , Adolescente , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Niño , Preescolar , Terapia Combinada , Sistemas de Computación , Dactinomicina/administración & dosificación , Resistencia a Antineoplásicos , Células Epiteliales/química , Proteínas HSP70 de Choque Térmico/análisis , Proteínas HSP70 de Choque Térmico/genética , Humanos , Lactante , Neoplasias Renales/tratamiento farmacológico , Neoplasias Renales/mortalidad , Neoplasias Renales/patología , Neoplasias Renales/cirugía , Proteínas de Neoplasias/análisis , Proteínas de Neoplasias/genética , Estadificación de Neoplasias , Células Madre Neoplásicas/química , Pronóstico , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Células del Estroma/química , Análisis de Supervivencia , Resultado del Tratamiento , Vincristina/administración & dosificación , Tumor de Wilms/tratamiento farmacológico , Tumor de Wilms/mortalidad , Tumor de Wilms/patología , Tumor de Wilms/cirugía
20.
Methods Mol Med ; 53: 139-50, 2001.
Artículo en Inglés | MEDLINE | ID: mdl-21318793

RESUMEN

Matrix metalloproteinases (MMPs) are a group of 16 enzymes that are capable of degrading extracellular matrix components. Their catalytic function is dependent on a zinc ion in the active center. MMPs are separated in three groups: gelatinases (type IV-collagenases), stromelysins, and interstitial collagenases. Their physiological and pathological significance is to modulate the extracellular matrix-e. g., in embryogenesis, in the ovarian cycles, or in inflammatory diseases such as rheumatoid arthritis or fibrosis of the liver or kidney (1,2).

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