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1.
Tribol Int ; 109: 586-592, 2017 May.
Artículo en Inglés | MEDLINE | ID: mdl-28469288

RESUMEN

The menisci protect the articular cartilage by reducing contact pressure in the knee. To restore their function after injury, a new silk fibroin replacement scaffold was developed. To elucidate its tribological properties, friction of the implant was tested against cartilage and glass, where the latter is typically used in tribological cartilage studies. The silk scaffold exhibited a friction coefficient against cartilage of 0.056, which is higher than meniscus against cartilage but in range of the requirements for meniscal replacements. Further, meniscus friction against glass was lower than cartilage against glass, which correlated with the surface lubricin content. Concluding, the tribological properties of the new material suggest a possible long-term chondroprotective function. In contrast, glass always produced high, non-physiological friction coefficients.

2.
Osteoarthritis Cartilage ; 24(12): 2171-2180, 2016 12.
Artículo en Inglés | MEDLINE | ID: mdl-27514995

RESUMEN

OBJECTIVE: Mechanical trauma of articular cartilage results in cell loss and cytokine-driven inflammatory response. Subsequent accumulation of reactive oxygen (ROS) and nitrogen (RNS) species enhances the enzymatic degradation of the extracellular matrix (ECM). This study aims on the therapeutic potential of N-acetyl cysteine (NAC) in a human ex vivo cartilage trauma-model, focusing on cell- and chondroprotective features. DESIGN: Human full-thickness cartilage explants were subjected to a defined impact trauma (0.59 J) and treated with NAC. Efficiency of NAC administration was evaluated by following outcome parameters: cell viability, apoptosis rate, anabolic/catabolic gene expression, secretion and activity of matrix metalloproteinases (MMPs) and proteoglycan (PG) release. RESULTS: Continuous NAC administration increased cell viability and reduced the apoptosis rate after trauma. It also suppressed trauma-induced gene expression of ECM-destructive enzymes, such as ADAMTS-4, MMP-1, -2, -3 and -13 in a dosage- and time-depending manner. Subsequent suppression of MMP-2 and MMP-13 secretion reflected these findings on protein level. Moreover, NAC inhibited proteolytic activity of MMPs and reduced PG release. CONCLUSION: In the context of this ex vivo study, we showed not only remarkable cell- and chondroprotective features, but also revealed new encouraging findings concerning the therapeutically effective concentration and treatment-time regimen of NAC. Its defense against chondrocyte apoptosis and catabolic enzyme secretion recommends NAC as a multifunctional add-on reagent for pharmaceutical intervention after cartilage injury. Taken together, our data increase the knowledge on the therapeutic potential of NAC after cartilage trauma and presents a basis for future in vivo studies.


Asunto(s)
Cartílago , Acetilcisteína , Condrocitos , Matriz Extracelular , Humanos , Proteoglicanos
3.
Cell Biosci ; 6: 11, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-26877866

RESUMEN

BACKGROUND: Progenitor cells display interesting features for tissue repair and reconstruction. In the last years, such cells have been identified in different cartilage types. In this study, we isolated a migrative subpopulation of adult human nasoseptal chondrocytes with progenitor cell features by outgrowth from human nasal septum cartilage. These putative progenitor cells were comparatively characterized with mesenchymal stem cells (MSC) and human nasal septum chondrocytes with respect to their cellular characteristics as well as surface marker profile using flow cytometric analyses. Differentiation capacity was evaluated on protein and gene expression levels. RESULTS: The migrative subpopulation differentiated into osteogenic and chondrogenic lineages with distinct differences to chondrocytes and MSC. Cells of the migrative subpopulation showed an intermediate surface marker profile positioned between MSC and chondrocytes. Significant differences were found for CD9, CD29, CD44, CD90, CD105 and CD106. The cells possessed a high migratory ability in a Boyden chamber assay and responded to chemotactic stimulation. To evaluate their potential use in tissue engineering applications, a decellularized septal cartilage matrix was either seeded with cells from the migrative subpopulation or chondrocytes. Matrix production was demonstrated immunohistochemically and verified on gene expression level. Along with secretion of matrix metalloproteinases, cells of the migrative subpopulation migrated faster into the collagen matrix than chondrocytes, while synthesis of cartilage specific matrix was comparable. CONCLUSIONS: Cells of the migrative subpopulation, due to their migratory characteristics, are a potential cell source for in vivo regeneration of nasal cartilage. The in vivo mobilization of nasal cartilage progenitor cells is envisioned to be the basis for in situ tissue engineering procedures, aiming at the use of unseeded biomaterials which are able to recruit local progenitor cells for cartilage regeneration.

4.
Br J Pharmacol ; 160(5): 1252-62, 2010 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-20590617

RESUMEN

BACKGROUND AND PURPOSE: A main challenge in the therapy of osteoarthritis (OA) is the development of drugs that will modify the disease. Reliable test systems are necessary to enable an efficient screening of therapeutic substances. We therefore established a chondrocyte-based in vitro cell culture model in order to characterize different p38MAPK inhibitors. EXPERIMENTAL APPROACH: Interleukin-1beta (IL-1beta)-stimulated human OA chondrocytes were treated with the p38MAPK inhibitors Birb 796, pamapimod, SB203580 and the new substance CBS-3868. Birb 796- and SB203580-treated cells were analysed in a genome-wide microarray analysis. The efficacy of all inhibitors was characterized by quantitative gene expression analysis and the quantification of PGE(2) and NO release. KEY RESULTS: Microarray analysis revealed inhibitor-specific differences in gene expression. Whereas SB203580 had a broad effect on chondrocytes, Birb 796 counteracted the IL-1beta effect more specifically. All p38MAPK inhibitors significantly inhibited the IL-1beta-induced gene expression of COX-2, mPGES1, iNOS, matrix metalloproteinase 13 (MMP13) and TNFRSF11B, as well as PGE(2) release. Birb 796 and CBS-3868 showed a higher efficacy than SB203580 and pamapimod at inhibiting the expression of COX-2 and MMP13 genes, as well as PGE(2) release. In the case of mPGES1 and TNFRSF11B gene expression, CBS-3868 exceeded the efficacy of Birb 796. CONCLUSIONS AND IMPLICATIONS: Our test system could differentially characterize inhibitors of the same primary pharmaceutical target. It reflects processes relevant in OA and is based on chondrocytes that are mainly responsible for cartilage degradation. It therefore represents a valuable tool for drug screening in between functional in vitro testing and in vivo models.


Asunto(s)
Condrocitos/efectos de los fármacos , Condrocitos/metabolismo , Evaluación Preclínica de Medicamentos/métodos , Expresión Génica/efectos de los fármacos , Mediadores de Inflamación/metabolismo , Interleucina-1beta/antagonistas & inhibidores , Inhibidores de Proteínas Quinasas/farmacología , Proteínas Quinasas p38 Activadas por Mitógenos/antagonistas & inhibidores , Técnicas de Cultivo de Célula , Dinoprostona/metabolismo , Humanos , Interleucina-1beta/farmacología , Óxido Nítrico/metabolismo , Análisis de Secuencia por Matrices de Oligonucleótidos/métodos
5.
Unfallchirurg ; 110(2): 116-23, 2007 Feb.
Artículo en Alemán | MEDLINE | ID: mdl-17123043

RESUMEN

BACKGROUND: Follow-up of patients with pelvic ring fractures and associated injuries of the lower urogenital tract was performed from January 2000 to October 2004. Analysis focused on incidence, fracture type, type of urogenital injury, associated intrapelvic lesions, mortality, and urologic outcome. METHOD AND RESULTS: The retrospective study included 18 of 111 patients (16.2%). Nine patients had a rupture of the urethra, six a rupture of the bladder, three a rupture of the penile root, and two a gonadal defect. The type of the pelvic ring fracture according to the AO classification was type A in 1, type B in 6, and type C in 11 cases. Fifteen patients (83.3%) were followed up clinically for a mean duration of 26 months (range: 12-66 months) after trauma. Seven patients were asymptomatic concerning the urogenital injury, five had erectile dysfunction, two had urethral stenosis, in one case associated with incontinence, and one patient with bilateral defect of the testicles was under hormone substitution therapy. CONCLUSION: Urogenital injuries, often associated with intrapelvic lesions in so-called complex pelvic trauma, are typical for high-grade pelvic ring fractures and have an essential prognostic value for the patient's morbidity and quality of life.


Asunto(s)
Fracturas Óseas/diagnóstico , Traumatismo Múltiple/diagnóstico , Huesos Pélvicos/lesiones , Pene/lesiones , Testículo/lesiones , Uretra/lesiones , Vejiga Urinaria/lesiones , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Estudios Transversales , Femenino , Fijación Interna de Fracturas , Fracturas Óseas/epidemiología , Fracturas Óseas/cirugía , Humanos , Puntaje de Gravedad del Traumatismo , Masculino , Persona de Mediana Edad , Traumatismo Múltiple/epidemiología , Traumatismo Múltiple/cirugía , Huesos Pélvicos/cirugía , Pene/cirugía , Rotura , Testículo/cirugía , Tomografía Computarizada por Rayos X , Uretra/cirugía , Vejiga Urinaria/cirugía , Urografía
6.
Neuropediatrics ; 36(3): 210-3, 2005 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-15944908

RESUMEN

Severe myoclonic epilepsy in infancy (SMEI), severe idiopathic generalized epilepsy of infancy (SIGEI) with generalized tonic clonic seizures (GTCS), and myoclonic astatic epilepsy (MAE) may show semiological overlaps. In GEFS+ families, all three phenotypes were found associated with mutations in the SCN1A gene. We analyzed the SCN1A gene in 20 patients with non-familial myoclonic astatic epilepsy -- including 12 probands of the original cohort used by Doose et al. in 1970 to delineate MAE. In addition, 18 patients with sporadic SIGEI -- mostly without myoclonic-astatic seizures -- were analyzed. Novel SCN1A mutations were found in 3 individuals. A frame shift resulting in an early premature stop codon in a now 35-year-old woman with a borderline phenotype of MAE and SIGEI (L433fsX449) was identified. A splice site variant (IVS18 + 5 G --> C) and a missense mutation in the conserved pore region (40736 C --> A; R946 S) were detected each in a child with SIGEI. We conclude that, independent of precise syndromic delineation, myoclonic-astatic seizures are not predictive of SCN1A mutations in sporadic myoclonic epilepsies of infancy and early childhood.


Asunto(s)
Epilepsias Mioclónicas/genética , Epilepsia Tónico-Clónica/genética , Proteínas del Tejido Nervioso/genética , Canales de Sodio/genética , Niño , Desarrollo Infantil , Análisis Mutacional de ADN , Epilepsias Mioclónicas/fisiopatología , Epilepsias Mioclónicas/psicología , Epilepsia Tónico-Clónica/fisiopatología , Epilepsia Tónico-Clónica/psicología , Femenino , Estudios de Seguimiento , Humanos , Lactante , Masculino , Canal de Sodio Activado por Voltaje NAV1.1
7.
J Neurol Neurosurg Psychiatry ; 75(8): 1186-8, 2004 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-15258228

RESUMEN

Mutations in the gene encoding Cu/Zn superoxide dismutase (SOD1) account for approximately 20% of patients with familial amyotrophic lateral sclerosis (FALS). In this study, sequence analysis of exons 1-5 of SOD1 in a large German cohort with FALS was performed. Among 75 affected patients, who were not obviously related probands with a positive family history, nine had missense mutations in SOD1. Four of the nine probands carry the same R115G mutation in exon 4 of the SOD1 gene. Genotyping with markers from the SOD1 locus revealed a common haplotype and shared allelic characteristics in these patients. These findings suggest that the R115G mutation in the German population originates from a common founder.


Asunto(s)
Esclerosis Amiotrófica Lateral/genética , Superóxido Dismutasa/genética , Adulto , Anciano , Análisis Mutacional de ADN , Exones/genética , Femenino , Genotipo , Alemania , Humanos , Masculino , Persona de Mediana Edad , Análisis de Secuencia de ADN , Superóxido Dismutasa-1
8.
Int J Radiat Oncol Biol Phys ; 50(4): 909-13, 2001 Jul 15.
Artículo en Inglés | MEDLINE | ID: mdl-11429218

RESUMEN

PURPOSE: Testicular intraepithelial neoplasia (TIN) is a consistent precursor of most invasive germ cell tumors, currently treated by radiotherapy with 20 Gy, which destroys TIN but preserves Leydig cells. Nevertheless, analysis has shown dose-dependent dysfunction even with low therapeutic doses of 20 Gy in some cases. Therefore, we tested a dose reduction regimen by delivering smaller fractional doses to enhance the tolerance of Leydig cells. METHODS AND MATERIALS: Between 1993 and 1999, 9 patients were treated for TIN in a prospective multicenter trial. A total dose of 13 Gy was administered in 10 fractions of 1.3 Gy. Hormonal levels of follicle-stimulating hormone, luteinizing hormone, and testosterone were assayed serially. RESULTS: During a median follow-up time of 36 months, no patient showed evidence of local disease. A first postradiation biopsy was obtained 3-12 months after radiotherapy; 5 patients underwent a second biopsy 2-3 years after treatment. All biopsies showed a Sertoli cell-only pattern. Follicle-stimulating hormone levels continued to increase 1 year after radiotherapy, signaling eradicated spermiogenesis. Luteinizing hormone and testosterone remained within the normal range 2 years after radiotherapy. CONCLUSIONS: In the treatment of TIN, there seems to be a dose reduction potential to 13 Gy by lowering single fractional doses, which enhances the therapeutic ratio in favor of the Leydig cells.


Asunto(s)
Carcinoma in Situ/radioterapia , Neoplasias Testiculares/radioterapia , Adulto , Biomarcadores/sangre , Carcinoma in Situ/sangre , Fraccionamiento de la Dosis de Radiación , Hormona Folículo Estimulante/sangre , Estudios de Seguimiento , Humanos , Células Intersticiales del Testículo/efectos de la radiación , Hormona Luteinizante/sangre , Masculino , Tolerancia a Radiación , Espermatogonias/efectos de la radiación , Neoplasias Testiculares/sangre , Testosterona/sangre
9.
Biochem J ; 354(Pt 2): 345-50, 2001 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-11171113

RESUMEN

The role of mitochondria in stimulus-secretion coupling of pancreatic beta-cells was examined using methyl pyruvate (MP). MP stimulated insulin secretion in the absence of glucose, with maximal effect at 5 mM. K+ (30 mM) alone, or in combination with diazoxide (100 microM), failed to enhance MP-induced secretion. Diazoxide (100 microM) inhibited MP-induced insulin secretion. MP depolarized the beta-cell in a concentration-dependent manner (5-20 mM). The sustained depolarization induced by 20 mM MP was not influenced by 100 microM diazoxide, but the continuous spiking activity was suppressed by 500 microM diazoxide. Pyruvate failed to initiate insulin release (5-20 mM) or to depolarize the membrane potential. ATP production in isolated beta-cell mitochondria was detected as accumulation of ATP in the medium during incubation in the presence of malate or glutamate in combination with pyruvate or MP. There was no difference in ATP production induced by pyruvate/malate or MP/malate in isolated beta-cell mitochondria. ATP production by MP/glutamate was higher than that induced by pyruvate/glutamate, but it was much lower than that induced by alpha-ketoisocaproate/glutamate. Pyruvate (5 mM) or MP (5 mM) had no effect on the ATP/ADP ratio in whole islets, whereas glucose (20 mM) significantly increased the whole islet ATP/ADP ratio. It is concluded that MP-induced beta-cell membrane depolarization or insulin release does not relate directly to mitochondrial ATP production. Instead MP may exert a direct extramitochondrial effect, or it may stimulate beta-cell mitochondria to produce coupling factors different from ATP to initiate insulin release.


Asunto(s)
Insulina/metabolismo , Islotes Pancreáticos/efectos de los fármacos , Piruvatos/farmacología , Adenosina Difosfato/metabolismo , Adenosina Trifosfato/metabolismo , Animales , Células Cultivadas , Glucosa/farmacología , Secreción de Insulina , Islotes Pancreáticos/metabolismo , Islotes Pancreáticos/fisiología , Potenciales de la Membrana/efectos de los fármacos , Ratones , Mitocondrias/efectos de los fármacos , Mitocondrias/metabolismo , Ácido Pirúvico/farmacología
10.
Oncogene ; 18(47): 6488-95, 1999 Nov 11.
Artículo en Inglés | MEDLINE | ID: mdl-10597251

RESUMEN

Hematopoietic cell growth, differentiation, and commitment to a restricted lineage are guided by a set of cytokines acting exclusively on cells expressing the corresponding cytokine receptor. The macrophage colony stimulating factor (M-CSF, also termed CSF-1) and its cognate receptor, the tyrosine kinase c-Fms, are essential for monocyte and macrophage development. The underlying molecular mechanism, however, is poorly understood. Here we identified a novel Fms-interacting protein (FMIP, MW 78 kDa) which binds transiently via its N-terminal 144 residues to the cytoplasmic domain of activated Fms-molecules. Binding of FMIP was paralleled by rapid tyrosine phosphorylation within the binding domain which drastically reduced its ability to associate with Fms. Binding was specific as evidenced by co-immunoprecipitation and association with recombinant GST-Fms fusion proteins. No binding was observed with the tyrosine phosphorylated cytoplasmic domains of c-Kit, TrkA, c-Met, and the insulin receptor. The role of FMIP in hematopoietic differentiation was studied in the bipotential myeloid progenitor cell line, FDC-P1Mac11. Overexpression of FMIP prevented M-CSF induced macrophage differentiation. Instead, cells differentiated into granulocytes. Our data suggest that the level of FMIP expression could form a threshold that decides about differentiation either into macrophages or into granulocytes.


Asunto(s)
Proteínas Portadoras/metabolismo , Diferenciación Celular , Granulocitos/citología , Péptidos y Proteínas de Señalización Intracelular , Macrófagos/citología , Secuencia de Aminoácidos , Proteínas Portadoras/química , Proteínas Portadoras/genética , Línea Celular , Factor Estimulante de Colonias de Macrófagos/fisiología , Datos de Secuencia Molecular , Fosforilación , Unión Proteica , Proteínas Tirosina Quinasas Receptoras/metabolismo , Receptor de Factor Estimulante de Colonias de Macrófagos/metabolismo , Especificidad por Sustrato
11.
Strahlenther Onkol ; 175(7): 320-4, 1999 Jul.
Artículo en Alemán | MEDLINE | ID: mdl-10432993

RESUMEN

PURPOSE: To review patterns of relapse in a long-term analysis of patients with Stage I seminoma treated by orchidectomy and radiotherapy to the paraaortic lymph nodes only and to follow follicle stimulating hormone (FSH) levels dependent on testicular scatter dose. PATIENTS AND METHODS: From 1980 to 1995, 58 patients with Stage I seminoma received elective radiotherapy to the paraaortic lymph nodes only (Th12 to L4), with a mean total dose of 28.07 Gy (+/- 2.2 SD), using fractional doses between 1.5 and 2 Gy (mean 1.62 Gy +/- 0.083 SD). Since 1989, testicular scatter doses were measured routinely by in-vivo thermoluminescent dosimetry (TLD) in 45 patients. In 26 patients with normal pre-treatment values of FSH, FSH-levels were repeatedly controlled after radiotherapy in order to evaluate any radiation-induced sequelae. RESULTS: During a mean observation period of 69.4 months (range 30 to 210), 2 out of 57 patients (3.5%) developed regional recurrences in the ipsilateral pelvic lymph nodes 14 months and 5 years after radiotherapy, respectively. One patient was lost to follow-up. The relapse-free survival rate at 5 years was 96.5% after radiotherapy alone. After salvage chemotherapy, both relapse-free survival and overall survival rates come to 100%. The mean testicular scatter dose in 45 patients was 0.22 Gy (+/- 0.087 SD). Seven out of 26 patients (26.9%) developed a transient increase of FSH-levels, reaching peak values at 4.2 months and returning to normal ranges within 18 months after radiotherapy. Below 0.2 Gy, no effect on FSH was observed. Testicular scatter doses showed no clear correlation to FSH risings (Figure 1). CONCLUSION: After exclusive paraaortic radiation of Stage I seminoma, even at follow-up periods in excess of 5 years the incidence of pelvic lymph node relapses remains below 4%. However, there seems to be a small potential for the development of late recurrences. With limited radiotherapy, permanent radiation-induced effects on the remaining testicle are very unlikely.


Asunto(s)
Infertilidad Masculina/etiología , Irradiación Linfática , Traumatismos por Radiación/etiología , Seminoma/radioterapia , Neoplasias Testiculares/radioterapia , Adulto , Aorta Abdominal , Terapia Combinada , Fraccionamiento de la Dosis de Radiación , Hormona Folículo Estimulante/sangre , Estudios de Seguimiento , Humanos , Metástasis Linfática , Masculino , Persona de Mediana Edad , Recurrencia Local de Neoplasia/mortalidad , Estadificación de Neoplasias , Dosificación Radioterapéutica , Radioterapia Adyuvante , Dispersión de Radiación , Seminoma/mortalidad , Seminoma/patología , Tasa de Supervivencia , Neoplasias Testiculares/mortalidad , Neoplasias Testiculares/patología
12.
Oncogene ; 17(20): 2593-600, 1998 Nov 19.
Artículo en Inglés | MEDLINE | ID: mdl-9840922

RESUMEN

Apoptotic cell death was shown to be accompanied or preceded by an elevated expression of the c-fos protooncogene and DNA binding activity of transcription factor AP-1. We used Fos-deficient mice to study the role of c-Fos during programmed cell death in the prostate. In normal mice apoptosis is induced in the prostate within 2-4 days after castration. Histological features of reduced secretory activity and morphological signs of programmed cell death become obvious. No apparent decrease in secretory activity and no epithelial cell death were observed in Fos-deficient animals after castration. Fragmentation of nuclear DNA was measured by in situ terminal transferase reaction. DNA fragmentation was observed in the prostate epithelium of control mice after castration whereas no similar fragmentation was found in Fos-deficient animals. After castration an AP-1 complex accumulated in the prostate of Fos deficient mice which mainly consists of FosB, Fra-2 and JunD whereas in control animals the AP-1 complex in addition contained c-Fos. Our data strongly suggest that c-Fos is required for programmed cell death of prostate epithelial cells.


Asunto(s)
Apoptosis/fisiología , Genes fos , Orquiectomía , Próstata/patología , Proteínas Proto-Oncogénicas c-fos/fisiología , Factor de Transcripción AP-1/fisiología , Animales , Atrofia , Proteínas Bacterianas/aislamiento & purificación , Proteínas de Unión al ADN/aislamiento & purificación , Antígeno 2 Relacionado con Fos , Sustancias Macromoleculares , Masculino , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Proteínas Proto-Oncogénicas c-fos/aislamiento & purificación , Proteínas Proto-Oncogénicas c-jun/aislamiento & purificación , Espermatogénesis , Testículo/patología , Factor de Transcripción AP-1/aislamiento & purificación , Factores de Transcripción/aislamiento & purificación
13.
Oncogene ; 15(13): 1565-72, 1997 Sep 25.
Artículo en Inglés | MEDLINE | ID: mdl-9380408

RESUMEN

Tyrosine autophosphorylation of the v-Fms oncogene product results in the formation of high-affinity binding sites for cellular proteins containing Src homology 2 (SH2) domains. These proteins transduce various mitogenic and morphogenic signals. As reported previously, Y696KNI in the kinase insert domain of v-Fms binds to the growth factor receptor bound protein 2 (Grb2), a stimulator of the Ras/Raf1 pathway. Here, we mapped Y921TNL within the C-terminal domain of Fms as a novel autophosphorylation site. We demonstrate that this site constitutes a second Grb2 binding site: a recombinant fusion protein (residues 904-944) containing phosphorylated Y921 bound Grb2 from FDCP-1Mac11 cell extracts significantly more efficiently than a corresponding protein (residues 617-759) containing Y696. A yeast two-hybrid system which allowed the formation of a functional Fms tyrosine kinase was employed to quantify binding of Grb2. Fms-protein containing either one of the two phosphorylation sites bound Grb2 equally well, binding was increased for proteins carrying both sites. In contrast, the simultaneous substitution of Y696 and Y921 by phenylalanines abolished Grb2 binding. Mouse NIH3T3 cells expressing the Y921F mutant Fms-protein showed a substantially higher content of fibronectin network than wild-type transformed cells and had largely lost their serum independent growth phenotype.


Asunto(s)
Proteínas Adaptadoras Transductoras de Señales , Proteína Oncogénica gp140(v-fms)/química , Proteínas/metabolismo , Células 3T3 , Animales , Sitios de Unión , Línea Celular Transformada , Proteína Adaptadora GRB2 , Ratones , Mutación , Mapeo Peptídico , Fosforilación , Proteínas Tirosina Quinasas/metabolismo , Proteínas Recombinantes/metabolismo , Dominios Homologos src
14.
Radiother Oncol ; 43(2): 159-62, 1997 May.
Artículo en Inglés | MEDLINE | ID: mdl-9192961

RESUMEN

BACKGROUND AND PURPOSE: In patients with stage I seminoma treated with elective lymph node irradiation, testicular scatter doses are often thought to be responsible for later disturbances in fertility. We studied the influence of radiation field extensions and testicular doses on hormonal function. MATERIALS AND METHODS: FSH (follicle stimulating hormone) and LH (luteinizing hormone) were evaluated before radiotherapy (RT) and by serial analyses after treatment for 4 years. Twenty-three patients were irradiated by hockey stick fields with a mean dose of 31.9 Gy (+/-4.7 SD) and a mean scatter dose of 54 8 cGy (+/-16.6 SD). Twenty-one patients received limited RT to the paraaortic nodes with 28.1 Gy (+/-2.4 SD). The mean testicular dose was only 25 cGy (+/-7.8 SD). All patients had normal pre-treatment hormonal values. RESULTS: Six months after the end of RT, mean FSH values were significantly elevated in the hockey stick group (P = 0.032), returning to normal after 3 years. The increase in LH was also significant, but stayed within normal ranges. Limited RT resulted in a minimal, dose-dependent increase of FSH; no changes in LH were noted. CONCLUSIONS: In patients with a normal hormonal status after semicastration, FSH is a reliable monitor for transient radiation-induced effects. To avoid treatment-related disturbances in spermatogenesis, scatter doses should be reduced to less than 20 cGy.


Asunto(s)
Hormonas/sangre , Seminoma/radioterapia , Neoplasias Testiculares/radioterapia , Adulto , Estradiol/sangre , Hormona Folículo Estimulante/sangre , Humanos , Hormona Luteinizante/sangre , Masculino , Radioterapia/métodos , Dosificación Radioterapéutica , Seminoma/sangre , Seminoma/patología , Neoplasias Testiculares/sangre , Neoplasias Testiculares/patología , Testosterona/sangre
15.
Int J Androl ; 20(2): 92-5, 1997 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-9292319

RESUMEN

The estimation of alpha-glucosidase activity in semen is widely used as a marker of epididymal function. In the present studies, glucosidase activity was evaluated in the different segments of the rat epididymis under various physiological conditions. In addition, the effect of two known male antifertility agents, gossypol and alpha-chlorohydrin, on enzyme activity was evaluated. Enzyme activity was absent from the epididymis of rats aged 10 and 20 days but became detectable at 30 days of age when the adult pattern of distribution (highest activity in the caput epididymis) was established. Enzyme activity was reduced significantly in all segments of the epididymis at 7 days after castration and a significant decrease in activity was also observed following the administration of either gossypol or alpha-chlorohydrin. These findings are consistent with a role for alpha-glucosidase in sperm maturation in the epididymis.


Asunto(s)
Anticonceptivos Masculinos/farmacología , Epidídimo/fisiología , alfa-Glucosidasas/metabolismo , Envejecimiento/metabolismo , Animales , Epidídimo/enzimología , Epidídimo/crecimiento & desarrollo , Gosipol/farmacología , Cinética , Masculino , Orquiectomía , Especificidad de Órganos , Ratas , alfa-Clorhidrina/farmacología
16.
J Biol Chem ; 271(40): 24476-81, 1996 Oct 04.
Artículo en Inglés | MEDLINE | ID: mdl-8798707

RESUMEN

Tyrosine autophosphorylation of the v-Fms oncogene product results in the formation of high affinity binding sites for cellular proteins with Src homology 2 (SH2) domains that are involved in various signal cascades. Tryptic digestion of the autophosphorylated v-Fms and of its cellular counterpart, the feline c-Fms polypeptide, gave rise to at least six common major phosphopeptides, four of which have been characterized previously. Employing site-directed mutagenesis and phosphopeptide mapping of in vitro phosphorylated glutathione S-transferase v-Fms fusion proteins as well as full-length v-Fms molecules expressed in various cells, we show here that Tyr543 of the juxtamembrane domain and Tyr696 of the kinase insert domain constitute major autophosphorylation sites. Recombinant fusion proteins containing the tyrosine-phosphorylated kinase insert domain bind the growth factor receptor bound protein 2 and the p85 and p110 subunits of phosphatidylinositol 3'-kinase. In contrast, fusion proteins containing the juxtamembrane domain phosphorylated on Tyr543 fail to bind any of the known SH2 domain-containing cellular proteins but associate specifically with an as yet undefined 55-kDa cellular protein that by itself is phosphorylated on tyrosine.


Asunto(s)
Proteína Oncogénica gp140(v-fms)/metabolismo , Proteínas/metabolismo , Tirosina/metabolismo , Células 3T3 , Animales , Gatos , Membrana Celular/metabolismo , Ratones , Fosfatidilinositol 3-Quinasas , Fosfopéptidos/metabolismo , Fosforilación , Fosfotransferasas (Aceptor de Grupo Alcohol)/metabolismo , Unión Proteica , Receptor de Factor Estimulante de Colonias de Macrófagos/metabolismo , Proteínas Recombinantes de Fusión/metabolismo
17.
Theor Appl Genet ; 92(2): 281-4, 1996 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-24166179

RESUMEN

Isolate WELA of the plant pathogenic oomycete fungus Peronospora parasitica causes downy mildew in the Arabidopsis thaliana ecotypes Weiningen (Wei-0) and La-er, whereas ecotypes RLD and Col-0 are resistant. Genetic crosses between resistant RLD and susceptible Wei-0 showed that resistance was inherited in a simple Mendelian fashion as a monogenic dominant trait. The interactions between different isolates of P. parasitica and ecotypes of A. thaliana show race-specific variation and fit a gene-for-gene relationship. The RPP11 resistance gene was mapped by following the co-segregation of the resistance phenotype with RFLP markers in a mapping population of 254 F3 families derived from RLD x Wei-0 F2 individuals. Linkage analysis using version 1.9 of the MAPMAKER program placed the RPP11 resistance locus on chromosome III between marker m249 (two recombinants) and marker g2534 (six recombinants). Markers g2534 and g4117 are on YAC EG7H1. Marker g4117 and one end probe (N5) generated from YAC EG7H1 showed no recombinants. The YAC end probe N5, which was generated by plasmid rescue, was used to screen clones in the Eric Ward YAC library and a YAC was fished (EW19B12) which also hybridised with m249. Thus, a YAC contig has been established over the region where the resistance locus maps. Because the YACs were made with ecotype Columbia DNA it is necessary to isolate the equivalent region from RLD in order to clone the resistance locus. To this end a phage λ-DASH (™) genomic library was prepared from RLD and a contig covering the relevant region of the YACs is currently under construction.

18.
Gene ; 160(1): 89-93, 1995 Jul 04.
Artículo en Inglés | MEDLINE | ID: mdl-7628724

RESUMEN

The tetracycline-resistance (TcR) determinant of the Enterococcus faecalis plasmid pJH1 has been identified and located on a 2.2-kb RsaI-EcoRI fragment. The fragment was cloned in Escherichia coli, and specified TcR in this host. The nucleotide (nt) sequence of the cloned fragment showed the presence of an open reading frame (ORF) of 1374 bp, designated tetL. The nt sequence of tetL from pJH1 was identical to that of the tetL present on pLS1 from Streptococcus agalactiae. Upstream of the pJH1 tetL, part of another ORF was found that, except for two single-nt substitutions, was identical to an iso-ISS1 element from Lactococcus lactis. Hybridization studies indicated the presence of several ISS1-like elements in plasmid pJH1, but not on the En. faecalis chromosome. To study its usefulness as a marker in Gram+ organisms, the pJH1 tetL was cloned on the broad-host-range plasmid pNZ124, resulting in pNZ280, that was found to give resistance to 40 micrograms Tc/ml in Lc. lactis and Bacillus subtilis.


Asunto(s)
Proteínas Bacterianas/genética , Elementos Transponibles de ADN , Farmacorresistencia Microbiana , Enterococcus faecalis/genética , Enterococcus faecalis/metabolismo , Plásmidos , Resistencia a la Tetraciclina/genética , Secuencia de Aminoácidos , Proteínas Bacterianas/biosíntesis , Secuencia de Bases , Clonación Molecular , Escherichia coli , Expresión Génica , Datos de Secuencia Molecular , Sistemas de Lectura Abierta , Mapeo Restrictivo
19.
Zentralbl Gynakol ; 116(5): 301-3, 1994.
Artículo en Alemán | MEDLINE | ID: mdl-8023629

RESUMEN

The breast is an unusual site for metastatic extra-mammalian tumors, for instance for renal cell carcinoma. In the literature only few cases are reported. Our two cases show the possibility of different metastatic forms in hypernephroma after nephrectomy 5 and 6 years before.


Asunto(s)
Neoplasias de la Mama/secundario , Carcinoma de Células Renales/secundario , Neoplasias Renales/cirugía , Biopsia , Mama/patología , Neoplasias de la Mama/patología , Neoplasias de la Mama/cirugía , Carcinoma de Células Renales/patología , Carcinoma de Células Renales/cirugía , Diagnóstico Diferencial , Femenino , Humanos , Neoplasias Renales/patología , Mastectomía Radical Modificada , Persona de Mediana Edad , Nefrectomía
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