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1.
Strahlenther Onkol ; 190(4): 358-63, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24638238

RESUMO

INTRODUCTION: The German Society of Radiation Oncology initiated a multicenter trial to evaluate core processes and subprocesses of radiotherapy by prospective evaluation of all important procedures in the most frequent malignancies treated by radiation therapy. The aim of this analysis was to assess the required resources for interstitial high-dose-rate (HDR) and low-dose-rate (LDR) prostate brachytherapy (BRT) based on actual time measurements regarding allocation of personnel and room occupation needed for specific procedures. PATIENTS AND METHODS: Two radiotherapy centers (community hospital of Offenbach am Main and community hospital of Eschweiler) participated in this prospective study. Working time of the different occupational groups and room occupancies for the workflow of prostate BRT were recorded and methodically assessed during a 3-month period. RESULTS: For HDR and LDR BRT, a total of 560 and 92 measurements, respectively, were documented. The time needed for treatment preplanning was median 24 min for HDR (n = 112 measurements) and 6 min for LDR BRT (n = 21). Catheter implantation with intraoperative HDR real-time planning (n = 112), postimplantation HDR treatment planning (n = 112), and remotely controlled HDR afterloading irradiation (n = 112) required median 25, 39, and 50 min, respectively. For LDR real-time planning (n = 39) and LDR treatment postplanning (n = 32), the assessed median duration was 91 and 11 min, respectively. Room occupancy and overall mean medical staff times were 194 and 910 min respectively, for HDR, and 113 and 371 min, respectively, for LDR BRT. CONCLUSION: In this prospective analysis, the resource requirements for the application of HDR and LDR BRT of prostate cancer were assessed methodically and are presented for first time.


Assuntos
Braquiterapia/estatística & dados numéricos , Recursos em Saúde/estatística & dados numéricos , Oncologia , Corpo Clínico/estatística & dados numéricos , Neoplasias da Próstata/epidemiologia , Neoplasias da Próstata/radioterapia , Carga de Trabalho/estatística & dados numéricos , Alemanha/epidemiologia , Humanos , Masculino , Planejamento da Radioterapia Assistida por Computador/estatística & dados numéricos , Estudos de Tempo e Movimento , Revisão da Utilização de Recursos de Saúde , Fluxo de Trabalho , Recursos Humanos
2.
Sci Rep ; 10(1): 18728, 2020 10 30.
Artigo em Inglês | MEDLINE | ID: mdl-33127943

RESUMO

The visual word form area (VWFA) in the left ventral occipito-temporal (vOT) cortex is key to fluent reading in children and adults. Diminished VWFA activation during print processing tasks is a common finding in subjects with severe reading problems. Here, we report fMRI data from a multicentre study with 140 children in primary school (7.9-12.2 years; 55 children with dyslexia, 73 typical readers, 12 intermediate readers). All performed a semantic task on visually presented words and a matched control task on symbol strings. With this large group of children, including the entire spectrum from severely impaired to highly fluent readers, we aimed to clarify the association of reading fluency and left vOT activation during visual word processing. The results of this study confirm reduced word-sensitive activation within the left vOT in children with dyslexia. Interestingly, the association of reading skills and left vOT activation was especially strong and spatially extended in children with dyslexia. Thus, deficits in basic visual word form processing increase with the severity of reading disability but seem only weakly associated with fluency within the typical reading range suggesting a linear dependence of reading scores with VFWA activation only in the poorest readers.


Assuntos
Dislexia/diagnóstico por imagem , Dislexia/fisiopatologia , Processamento de Texto , Encéfalo/diagnóstico por imagem , Encéfalo/fisiologia , Mapeamento Encefálico , Criança , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino , Reconhecimento Visual de Modelos/fisiologia , Percepção Visual
3.
Urologe A ; 56(3): 336-341, 2017 Mar.
Artigo em Alemão | MEDLINE | ID: mdl-28102436

RESUMO

BACKGROUND: A urethral stricture is a scar of the urethral epithelium which can cause obstructive voiding dysfunction with consequential damage of the upper urinary tract. Almost 45% of all strictures are iatrogenic; they develop in 2-9% of patients after radical prostatectomy, but can also occur after prostate cancer radiotherapy. This study provides 5­year data of a certified prostate cancer center (PKZ) in terms of urethral strictures. MATERIALS AND METHODS: Between 01/2008 and 12/2012 a total of 519 men were irradiated for prostate cancer (LDR and HDR brachytherapy as well as external beam radiation). The entire cohort was followed-up prospectively according to a standardized protocol (by type of irradiation). Short segment urethral strictures were treated by urethrotomy, recurrent and long segment stenosis with buccal mucosa urethroplasty. RESULTS: A total of 18 of 519 (3.4%) patients developed a urethral stricture post-therapeutically, which recurred in 66% of cases after the first operative treatment. The largest risk for developing a urethral stricture is attributed to the HDR brachytherapy (8.9%). CONCLUSION: Urethral strictures after prostate cancer radiotherapy should be diagnosed and treated in time for long-term preservation of renal function. The rate of radiogenic urethral strictures (3.4%) is equivalent to those after radical prostatectomy. Due to a high rate of recurrences, urethrotomy has a limited importance after irradiation.


Assuntos
Braquiterapia/estatística & dados numéricos , Neoplasias da Próstata/epidemiologia , Neoplasias da Próstata/radioterapia , Lesões por Radiação/epidemiologia , Radioterapia Conformacional/estatística & dados numéricos , Estreitamento Uretral/epidemiologia , Idoso , Idoso de 80 Anos ou mais , Causalidade , Comorbidade , Fracionamento da Dose de Radiação , Alemanha/epidemiologia , Humanos , Incidência , Estudos Longitudinais , Masculino , Pessoa de Meia-Idade , Lesões por Radiação/patologia , Fatores de Risco , Estreitamento Uretral/patologia
4.
Biochim Biophys Acta ; 697(2): 221-8, 1982 May 31.
Artigo em Inglês | MEDLINE | ID: mdl-6285978

RESUMO

At 0 degrees C, CHO cells efficiently incorporated [3H]thymidine into the nucleotide fraction, but not into DNA. Upon reincubation of asynchronous cultures at 37 degrees C, 15-25% of the radioactivity contained in the cellular nucleotide fraction was released, in the form of thymidine, into the culture medium. At 0 degrees C, however, radioactivity of the nucleotide fraction was retained within the cells. Similarly, dTMP phosphatase (EC 3.1.3.35) in cell extracts was active at 37 degrees C, but not at 0 degrees C, whereas thymidine kinase (EC 2.7.1.21) was active at both temperatures. If synchronous cultures in Gl phase were prelabeled at 0 degrees C and reincubated at 37 degrees C, almost all radioactivity in the nucleotide fraction was released into the medium, whereas in S-phase cultures nearly all radioactivity of the nucleotide fraction was incorporated into DNA. In synchronous S-phase cultures treated with hydroxyurea, radioactivity in the nucleotide fraction was released into the medium at a rate considerably lower than that observed for Gl-phase cells. Rates of endogenous synthesis of thymidine nucleotides were calculated from changes of cellular thymidine nucleotide content, incorporation of thymidine nucleotides into DNA and release of thymidine into the medium during reincubation of prelabeled cultures in thymidine-free medium. The results obtained (see Table III) reveal marked differences between Gl and S phases with respect to the determinants of thymidine nucleotide metabolism.


Assuntos
Nucleotídeos de Timina/metabolismo , Animais , Ciclo Celular , Linhagem Celular , Cricetinae , Cricetulus , Feminino , Cinética , Ovário , Monoéster Fosfórico Hidrolases/metabolismo , Técnica de Diluição de Radioisótopos , Timidina/metabolismo , Timidina Quinase/metabolismo , Trítio
5.
Biochim Biophys Acta ; 1009(1): 90-3, 1989 Sep 21.
Artigo em Inglês | MEDLINE | ID: mdl-2506931

RESUMO

Two heat-sensitive (reversibly arrested in G1 phase at 39.5 degrees C, multiplying at 33 degrees C) and two cold-sensitive (reversibly arrested in G1 phase at 33 degrees C, multiplying at 39.5 degrees C) cell-cycle mutants of the P-815-X2 murine mastocytoma line were tested for ribonucleotide reductase activity, using cells made permeable to nucleotides. After transfer of the heat-sensitive mutant cells to 39.5 degrees C, ribonucleotide reductase activity, similar to thymidine kinase (Schneider, E., Müller, B. and Schindler, R. (1983) Biochim. Biophys. Acta 741, 77-85), but unlike DNA polymerase alpha (Schneider, E., Müller, B. and Schindler, R. (1985) Biochim. Biophys. Acta 825, 375-383), decreased rapidly and in parallel with numbers of cells in S phase, whereas in the cold-sensitive mutant cells brought to 33 degrees C, ribonucleotide reductase activity decreased approx. 8 h later than numbers of DNA-synthesizing cells. When arrested heat- or cold-sensitive mutant cells were returned to the permissive temperature, ribonucleotide reductase activities, similar to DNA polymerase alpha and to thymidine kinase in heat-sensitive mutants, increased essentially in parallel with reentry of cells into S phase, whereas the increase in thymidine kinase activity in the cold-sensitive mutants was previously shown to occur approx. one cell-cycle time later. This indicates that ribonucleotide reductase and thymidine kinase are coordinately expressed in the heat-sensitive, but independently regulated in the cold-sensitive mutants.


Assuntos
Ciclo Celular , Mutação , Ribonucleotídeo Redutases/metabolismo , Animais , Temperatura Baixa , DNA/biossíntese , Temperatura Alta , Interfase , Sarcoma de Mastócitos , Camundongos , Timidina Quinase/metabolismo , Células Tumorais Cultivadas
6.
Cell Death Differ ; 10(4): 451-60, 2003 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-12719722

RESUMO

The mechanism of p53-dependent apoptosis is still only partly defined. Using early-passage embryonic fibroblasts (MEF) from wild-type (wt), p53(-/-) and bax(-/-) mice, we observe a p53-dependent translocation of Bax to the mitochondria and a release of mitochondrial Cytochrome c during stress-induced apoptosis. These events proceed independent of zVAD-inhibitable caspase activation, are not prevented by dominant negative FADD (DN-FADD), but are negatively regulated by Mdm-2. Bcl-x(L) expression prevents the release of mitochondrial Cytochrome c and apoptosis, but not Bax translocation. At a single-cell level, enforced expression of p53 is sufficient to induce Bax translocation and Cytochrome c release. Real-time RT-PCR analysis reveals a significant induction of RNA expression of Noxa and Bax in p53(+/+), but not in p53(-/-) MEF. Noxa protein expression becomes detectable prior to Bax translocation, and downregulation of endogenous Noxa by RNA interference protects wt MEF against p53-dependent apoptosis. Hence, in oncogene-expressing MEF p53 induces apoptosis by BH3 protein-dependent caspase activation.


Assuntos
Proteínas Adaptadoras de Transdução de Sinal , Apoptose/genética , Fibroblastos/enzimologia , Mitocôndrias/enzimologia , Proteínas Proto-Oncogênicas c-bcl-2/biossíntese , Proteínas Proto-Oncogênicas/deficiência , Proteína Supressora de Tumor p53/deficiência , Animais , Proteínas de Transporte/genética , Caspases/metabolismo , Células Cultivadas , Grupo dos Citocromos c/metabolismo , Regulação para Baixo/efeitos dos fármacos , Regulação para Baixo/genética , Inibidores Enzimáticos/farmacologia , Proteína de Domínio de Morte Associada a Fas , Feto , Fibroblastos/citologia , Regulação da Expressão Gênica/genética , Camundongos , Camundongos Knockout , Mitocôndrias/genética , Transporte Proteico/efeitos dos fármacos , Transporte Proteico/fisiologia , Proteínas Proto-Oncogênicas/genética , Proteínas Proto-Oncogênicas c-bcl-2/genética , Proteína Supressora de Tumor p53/genética , Proteína X Associada a bcl-2
7.
Leukemia ; 16(5): 846-54, 2002 May.
Artigo em Inglês | MEDLINE | ID: mdl-11986946

RESUMO

The Wilms tumor gene wt1 and the protooncogene bcl-2 are upregulated in acute myeloid leukemia (AML) and are known to regulate or to inhibit the onset of apoptosis. Since wt1 has been shown to regulate the expression of bcl-2, we investigated the association of the expression of these genes and their prognostic relevance in AML. Leukemic blasts from the bone marrow of 152 patients with newly diagnosed AML were analyzed for bcl-2 and wt1 mRNA expression using RT-PCR and quantitative PCR. Therapy outcome was correlated with the level of bcl-2 and wt1 transcripts. Bcl-2-specific mRNA was detectable in 127/152 (84%) patients and wt1 mRNA in 113/152 (74%) patients with AML. In monocytic subtypes the frequency of bcl-2 and wt1 transcripts was significantly lower. The expression of bcl-2 mRNA was correlated significantly with that of wt1 mRNA (P < 0.0001). In AML patients <60 years, high expression of bcl-2 and wt1 was associated with a reduced rate of continuing complete remission (CCR, P = 0.002 and P = 0.005, respectively) and increased death rate (P = 0.0002 and P = 0.04, respectively) in contrast to patients >60 years, where the expression of bcl-2 or wt1 had no prognostic impact. Based on the coexpression of bcl-2 and wt1, we established a prognostic model defining three risk groups with significant differences in CCR rate (P = 0.01), overall survival (P < 0.04) and disease-free survival (P < 0.03). Thus, bcl-2 and wt1 mRNA expression are associated with response and long-term outcome in AMLs. The coexpression of these genes allows determination of prognostic groups with high predictive value for overall and disease-free survival.


Assuntos
Leucemia Mieloide/genética , Leucemia Mieloide/mortalidade , Proteínas Proto-Oncogênicas c-bcl-2/genética , RNA Mensageiro/metabolismo , Proteínas WT1/genética , Doença Aguda , Adulto , Idoso , Idoso de 80 Anos ou mais , Apoptose/genética , Seguimentos , Humanos , Leucemia Mieloide/tratamento farmacológico , Pessoa de Meia-Idade , Prognóstico , Análise de Sobrevida , Resultado do Tratamento
8.
Leukemia ; 11(5): 709-13, 1997 May.
Artigo em Inglês | MEDLINE | ID: mdl-9180296

RESUMO

We established a factor-independent acute myeloid leukemia cell line, designated Ei501. The line has been growing in RPMI 1640 media for 18 months and can be maintained without addition of growth factors. Ei501 is positive for myeloperoxidase and negative for esterase and PAS. Cytogenetic analysis revealed the FAB M3 associated t(15;17) translocation and a translocation of the chromosomes 7 and 8: 46 XX, -7, +t(7;8)(q32;q13), t(15;17)(q22;q12). This karyotype was confirmed by fluorescence in situ hybridization. Ei501 cells express AML-associated surface markers such as CD13, CD33 and CD38. Although 42% of the patient's blast cells were CD34-positive, the line lacks surface expression of CD34. Furthermore the line has a number of characteristics which are detectable in blasts from AML patients, such as surface adhesion molecules, cytokines such as TGF-beta, cytokine receptors such as the IL-2 receptor beta and gamma chains or the IL-4 receptor and the genes for the transcription factor wt-1 (Wilms' tumor gene) and for the proto-oncogene bcl-2, both shown to be present in the majority of patients with AML. Additionally the line can be used as target in cytotoxicity assays using IL-2 activated cytotoxic lymphocytes as effector cells. In conclusion, besides a rare karyotype the Ei501 cell line has several features common in AML, and may therefore be used as a model to study pathogenetic mechanisms in acute myeloid leukemia.


Assuntos
Citocinas/biossíntese , Leucemia Mieloide Aguda/genética , Leucemia Mieloide Aguda/patologia , Translocação Genética , Adolescente , Antígenos CD/análise , Medula Óssea/patologia , Linhagem Celular , Mapeamento Cromossômico , Cromossomos Humanos Par 15 , Cromossomos Humanos Par 17 , Cromossomos Humanos Par 7 , Cromossomos Humanos Par 8 , Citocinas/genética , Primers do DNA , Feminino , Antígenos HLA/análise , Antígenos HLA-DR/análise , Humanos , Imunofenotipagem , Hibridização in Situ Fluorescente , Cariotipagem , Leucemia Mieloide Aguda/imunologia , Reação em Cadeia da Polimerase , Proto-Oncogene Mas , Células Tumorais Cultivadas
9.
Early Hum Dev ; 81(3): 281-7, 2005 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-15814210

RESUMO

The objective of this study was to assess minor neurological dysfunction, cognitive development, and somatic development after dexamethasone therapy in very-low-birthweight infants. Thirty-three children after dexamethasone treatment were matched to 33 children without dexamethasone treatment. Data were assessed at the age of 3-7 years. Dexamethasone was started between the 7th and the 28th day of life over 7 days with a total dose of 2.35 mg/kg/day. Exclusion criteria were asphyxia, malformations, major surgical interventions, small for gestational age, intraventricular haemorrhage grades III and IV, periventricular leukomalacia, and severe psychomotor retardation. Each child was examined by a neuropediatrician for minor neurological dysfunctions and tested by a psychologist for cognitive development with a Kaufman Assessment Battery for Children and a Draw-a-Man Test. There were no differences in demographic data, growth, and socio-economic status between the two groups. Fine motor skills and gross motor function were significantly better in the control group (p<0.01). In the Draw-a-Man Test, the control group showed better results (p<0.001). There were no differences in development of speech, social development, and the Kaufman Assessment Battery for Children. After dexamethasone treatment, children showed a higher rate of minor neurological dysfunctions. Neurological development was affected even without neurological diagnosis. Further long-term follow-up studies will be necessary to fully evaluate the impact of dexamethasone on neurological and cognitive development.


Assuntos
Cognição/efeitos dos fármacos , Dexametasona/efeitos adversos , Dexametasona/uso terapêutico , Glucocorticoides/efeitos adversos , Glucocorticoides/uso terapêutico , Recém-Nascido de muito Baixo Peso/fisiologia , Doenças do Sistema Nervoso/induzido quimicamente , Criança , Pré-Escolar , Cognição/fisiologia , Feminino , Humanos , Recém-Nascido , Recém-Nascido de muito Baixo Peso/psicologia , Masculino , Estudos Retrospectivos
10.
Exp Hematol ; 28(12): 1413-22, 2000 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-11146163

RESUMO

Identification of immunogenic leukemia-associated antigens as target structures is mandatory for specific immunotherapy of leukemia. Here, we define acute myeloid leukemia (AML) antigens eliciting a humoral immune response in the autologous host. We applied the method of serologic screening of cDNA expression libraries with autologous serum (SEREX). To date, this technique has been used to characterize antigen structures in solid tumors. The mRNA expression pattern of these newly in AML isolated antigens and previously described leukemia antigens (PRAME, MAGE-1, and Wt-1) was evaluated by reverse transcriptase polymerase chain reaction. For Wt-1, Western blotting also was performed. Screening of a cDNA expression library prepared from a patient with AML FAB M2 using autologous and allogeneic sera, followed by sequencing of positive clones, yielded three autoantigens (Prp1p/Zer1p, L19H1, and one without homology to previously described genes) and two antigens reactive with allogeneic sera (MAZ, PINCH). PRAME mRNA was expressed in 47% of 34 AML patients, but not in 13 CD34(+) cell samples or in peripheral blood mononuclear cells of 13 healthy volunteers. mRNA expression of MAZ was detected in 44% of AML patients, but only in 8% of healthy donors. Humoral responses to MAZ were detected in 35%. More than 80% of the screened AML patients showed simultaneous expression of two or more of these antigens.Differential expression in AML patients vs healthy volunteers suggests that the immunogenic antigens PRAME and MAZ are potential candidates for immunotherapy in AML.


Assuntos
Antígenos de Neoplasias/genética , Expressão Gênica , Leucemia Mieloide Aguda/imunologia , Proteínas Adaptadoras de Transdução de Sinal , Animais , Antígenos CD34/análise , Análise Mutacional de DNA , DNA Complementar/análise , Proteínas de Ligação a DNA/genética , Biblioteca Gênica , Humanos , Proteínas com Domínio LIM , Leucemia Mieloide Aguda/genética , Leucócitos Mononucleares/imunologia , Proteínas de Membrana , Camundongos , Camundongos Endogâmicos BALB C , RNA Mensageiro/análise , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Fatores de Transcrição/genética , Células Tumorais Cultivadas
11.
Exp Hematol ; 25(9): 945-50, 1997 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-9257807

RESUMO

The Wilms' tumor gene (wt1) is strongly expressed in malignant blasts of acute myeloid leukemia (AML) in approximately 80% of all cases. However, the role of wt1 expression in non malignant hematopoietic cells remains unclear. To characterize the expression of wt1 in differentiating hematopoietic progenitors, we isolated and cultured CD34+ progenitor cells from four healthy bone marrow donors with stem cell factor (SCF) and granulocyte colony stimulating-factor (G-CSF) to induce differentiation into granulocytes. Four different cultures were carried out for 12 days. During culture, wt1 mRNA expression was analyzed by defining its ratio relative to beta-actin using reverse transcriptase polymerase chain reaction (RT-PCR). To monitor the stage of differentiation, expression of cell surface markers and peroxidase was analyzed daily. The initial purity of CD34+ cells ranged between 80% and 90%; after 12 days, the frequency of neutrophil bands and segmented neutrophils was approximately 60%. Using RT-PCR to determine the ratio of wt1 to beta-actin expression, we reproducibly detected maximum expression of wt1 mRNA at day 0 in two cultures and at day 1 in two other CD34+ cell cultures; at both these time points nearly all cells fulfilled the morphological and immunephenotypical criteria of early hematopoietic blast cells. Wt1 expression dropped rapidly at day 1 and 2, respectively, in these two pairs of cultures, and was accompanied by an increase of cells expressing CD33 surface antigen. Our data suggest that wt1 expression is restricted to a subset of CD34+ progenitors and downregulated in later stages of differentiation in vitro.


Assuntos
Antígenos CD34/análise , Diferenciação Celular , Regulação da Expressão Gênica , Genes do Tumor de Wilms , Células-Tronco Hematopoéticas/metabolismo , Southern Blotting , Células da Medula Óssea , Regulação para Baixo , Fator Estimulador de Colônias de Granulócitos/farmacologia , Células-Tronco Hematopoéticas/imunologia , Humanos , Reação em Cadeia da Polimerase , RNA Mensageiro/análise , DNA Polimerase Dirigida por RNA , Fator de Células-Tronco/farmacologia
12.
Exp Hematol ; 29(10): 1226-35, 2001 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-11602325

RESUMO

OBJECTIVE: The Wilms' tumor gene product (WT1) was identified as a tumor suppressor in pediatric kidney tumors. Conversely, acute leukemias express WT1 at a high frequency, and leukemias with high levels of WT1 expressed by leukemic blast cells have a significantly worse prognosis, suggesting an oncogenic function of WT1 in leukemic cells. To address this issue, we developed five hammerhead ribozymes (RZ1-RZ5) designed to cleave various wt1-mRNA GUC-recognition sites and thus suppress wt1 expression. METHODS: Using in vitro transcribed ribozymes and truncated wt1 target RNAs as substrates, we performed in vitro cleavage assays. The sequence of two ribozymes was then cloned into the pCDNA3 expression vector containing a self-processing ribozyme cassette. Downregulation of wt1 due to ribozyme expression was analyzed in the human 293 embryonic kidney and the K562 chronic myeloid leukemia cell line by Western blotting and RT-PCR. Growth of stable transfected K562 cells was determined by proliferation analysis and 3H-thymidine incorporation. RESULTS: In vitro, the anti-wt1 ribozymes were able to recognize and cleave the target RNA in a highly sequence-specific and time-dependent manner. The ribozymes showed different catalytic activity. Coexpression of wt1 and the self-processing ribozymes pRZ3 and pRZ5, respectively, resulted in a significantly downregulated WT1 protein level when transiently transfected in 293 cells. Furthermore, stable transfection of pRZ3 and pRZ5 resulted in considerably reduced expression of endogenous wt1 in K562 cells, correlating with the inhibition of cell proliferation and the induction of cell death. CONCLUSION: Our data suggest that anti-wt1 ribozymes are a potent inhibitor of wt1 expression with possible implications for the inhibition of cell proliferation in leukemic cells.


Assuntos
RNA Catalítico/metabolismo , RNA Mensageiro/genética , Proteínas WT1/genética , Sequência de Bases , Domínio Catalítico , Divisão Celular , Linhagem Celular , Sistema Livre de Células , Clonagem Molecular , Primers do DNA , Regulação da Expressão Gênica , Vetores Genéticos , Humanos , Células K562 , Cinética , Modelos Genéticos , Dados de Sequência Molecular , Reação em Cadeia da Polimerase , Regiões Promotoras Genéticas , RNA Catalítico/genética , Proteínas Recombinantes/metabolismo , Especificidade por Substrato , Supressão Genética , Transcrição Gênica , Células Tumorais Cultivadas
13.
J Biochem ; 115(2): 248-56, 1994 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-8206874

RESUMO

The expression of neutral glycosphingolipids and gangliosides was investigated in mouse and rabbit skeletal muscle by means of biochemical and immunochemical techniques. Neutral glycosphingolipids from muscle of the inbred rabbit strain used in this study showed a simple TLC pattern, comprising mainly monohexosylceramide. In addition to this compound, lactosylceramide, lacto-N-neotetraosylceramide, globoside and Forssman GSL were detected in mouse muscle. The major ganglioside in both species was GM3; GM3 (Neu5Ac) and GM3(Neu5Gc) were found in a 3:1 ratio in mouse muscle, whereas the absence of GM3(Neu5Gc) is characteristic of rabbit muscle. As a general structural feature of all muscle GM3 gangliosides investigated, a C18 fatty acid and C18 sphingosine were the major components besides minor C22 and C24:1 fatty acids of the respective ceramide portions, as revealed by positive and negative ion FAB-MS. alpha 2-3 sialylated lacto-N-neotetraosyl-ceramide (sialylparagloboside) was expressed in both species, whereas the alpha 2-6 sialylated isomeric compound was found only in mouse muscle. Minute quantities of ganglio-series GM1, GD1a, GD1b, and GT1b were detected in muscles from both species. Glycosphingolipid expression could be confirmed immunohistochemically by examining transverse and longitudinal cryosections of skeletal muscle samples. The results provide the basis for the investigation of muscle specific glycosphingolipids that might modulate membrane protein functions in muscle.


Assuntos
Gangliosídeos/biossíntese , Glicoesfingolipídeos/biossíntese , Músculos/metabolismo , Animais , Sequência de Carboidratos , Cromatografia Líquida de Alta Pressão , Cromatografia em Camada Fina , Feminino , Gangliosídeos/análise , Gangliosídeos/química , Glicoesfingolipídeos/análise , Glicoesfingolipídeos/química , Imuno-Histoquímica , Espectrometria de Massas , Camundongos , Microscopia de Fluorescência , Dados de Sequência Molecular , Músculos/química , Coelhos , Distribuição Tecidual
14.
Leuk Lymphoma ; 25(5-6): 435-43, 1997 May.
Artigo em Inglês | MEDLINE | ID: mdl-9250813

RESUMO

The Wilms' tumor gene product (WT-1) is suggested to act as a tumor suppressor in childhood malignancies of the kidney and as a transcription factor with regulating activity on a number of growth and differentiation factors. Wt-1 has been shown to be expressed in blast cells of the vast majority of patients with acute myeloid and lymphoblastic leukemias (AL) by a number of workers. High levels of wt-1 mRNA expression in blast cells of newly diagnosed AML patients predict worse prognosis when compared to patients with no or low wt-1 mRNA expression. Patients achieving complete responses after chemotherapy usually lose detectable signals of wt-1. In relapse of the disease reoccurrence of wt-1 mRNA can be determined in almost all patients with initially detectable wt-1 mRNA. Using sensitive techniques such as reverse transcription polymerase chain reaction (RT-PCR) relapses are preceded by wt-1 expression in some cases. Although a subpopulation of normal hematopoietic precursor cells has also been shown to express message for wt-1, detectable levels of wt-1 during follow-ups in AML patients have been shown to be useful as a marker for residual blast populations or even to predict relapse of AML. Whether the high level of wt- expression is a non-specific phenomenon resulting from malignant transformation or whether it has an impact on the pathophysiology of AML or the uncontrolled growth of AML blasts is still controversial. However, there are indicators for an involvement of wt-1 in malignant events of AML blasts such as the downregulation of wt-1 in chemically induced differentiation of AML blast cell lines or the interactions of wt-1 with the protooncogene bcl-2 and the tumor suppressor gene p53. In conclusion, its possible relevance as an AML marker and its role in pathophysiological mechanisms in AML will still have to be defined in the future.


Assuntos
Proteínas de Ligação a DNA/biossíntese , Genes do Tumor de Wilms , Leucemia Mieloide/genética , Leucemia Mieloide/metabolismo , Fatores de Transcrição/biossíntese , Doença Aguda , Expressão Gênica , Humanos , Proteínas WT1
15.
Leuk Lymphoma ; 41(5-6): 655-8, 2001 May.
Artigo em Inglês | MEDLINE | ID: mdl-11378583

RESUMO

Screening for mutations by PCR-SSCP in exons 5 to 9 of the p53 gene in 38 bone marrow or peripheral blood specimens of patients with acute myeloid leukemia (AML) showed abnormal shifts in 9 cases. One reflected a mutation in exon 8, whereas in the other cases there were no exonic mutations identified by sequencing. As PCR primers were chosen annealing in the introns flanking the exon region, following sequencing of the encompassing introns identified 5 base substitutions at various sites in intron 7. Two of them have been described previously [1] and 3 novel polymorphisms could be identified. To determine whether these polymorphisms are linked to the pathogenesis of AML, we screened peripheral blood specimens of 26 healthy controls. We found identical base substitutions in 6 out of 26 controls. Our data suggest that these polymorphisms are not related to the pathogenesis of AML.


Assuntos
Leucemia Mieloide/genética , Polimorfismo Genético/genética , Proteína Supressora de Tumor p53/genética , Doença Aguda , Substituição de Aminoácidos , Células Sanguíneas , Medula Óssea , Estudos de Casos e Controles , Análise Mutacional de DNA , Humanos , Íntrons , Leucemia Mieloide/etiologia , Proteínas de Neoplasias/genética
16.
Fertil Steril ; 28(7): 737-40, 1977 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-872954

RESUMO

Forty 3-hour oral glucose tolerance tests (OGTTs) were performed in 10 assumedly healthy female volunteers 19 to 30 years old, each serving four times as her own control. Each subject was taking a sequential type oral contraceptive containing either 50 microgram of ethinylestradiol or 80 microgram of mestranol alternatingly in four consecutive treatment cycles. The OGTTs were performed on the 6th day of each cycle, during pure estrogen medication. Blood glucose and serum insulin values did not differ significantly under either estrogen as tested by the t-test for paired observations. Our results do not support the findings of others that mestranol has a more pronounced or even exclusively adverse effect on glucose tolerance as compared with ethinylestradiol.


PIP: 10 female volunteers (19-30 years) received ethinyl estradiol (EE) and mestranol (ME) in order to determine whether treatment would influence carbohydrate metabolism. EE dose was 50 mcg and ME dose was 80 mcg. In each treatment cycle the estrogenic compound was given for 7 days, followed by 15 days of combined treatment with a gestagenic compound and a treatment-free interval of 6 days during which withdrawal bleeding occurred. On the 6th day of each treatment cycle on oral glucose tolerance test (OGTT) was performed. Blood smaples were obtained every 30 minutes over 3 hours and assayed for blood glucose and for serum insulin. The differences in blood glucose levels or serum insulin between EE cycles and ME cycles were insignificant.


Assuntos
Glicemia , Anticoncepcionais Orais Sequenciais/farmacologia , Anticoncepcionais Orais/farmacologia , Etinilestradiol/farmacologia , Insulina/sangue , Mestranol/farmacologia , Adulto , Metabolismo dos Carboidratos , Feminino , Teste de Tolerância a Glucose , Humanos , Gravidez
17.
Thromb Res ; 91(4): 183-90, 1998 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-9736421

RESUMO

In a pilot study, alterations of polymorphonuclear neutrophil function during systemic thrombolysis in acute myocardial infarction have been investigated in humans. The following parameters of neutrophil function were measured before and at 15 and 45 minutes after initiation of systemic thrombolysis with a recombinant tissue-type plasminogen activator in 20 patients with acute myocardial infarction: (1) neutrophil adhesion and (2) neutrophil activation. During systemic thrombolysis a significant decrease was observed in neutrophil adhesion (5.5+/-6.4 to 3.2+/-3.3; p<0.05), in phagocyting neutrophil activation (39+/-18 to 25+/-14%; p<0.05), and in resting neutrophil activation (9+/-7 to 3+/-4%; p<0.05). Successful reperfusion coincided with a significantly higher reduction of phagocyting neutrophil activation (40+/-14 to 20+/-12% vs. 39+/-24 to 26+/-19% in unsuccessful reperfusion; p<0.05), and of neutrophil adhesion (6.2+/-5.7 to 2.7+/-3.0 vs. 4.1+/-3.8 to 3.5+/-4.0 in unsuccessful reperfusion; p<0.05) during thrombolysis. Systemic thrombolysis in acute myocardial infarction is accompanied by a reduction in neutrophil adhesion and activation dependent on thrombolytic success.


Assuntos
Fibrinolíticos/administração & dosagem , Infarto do Miocárdio/sangue , Ativação de Neutrófilo/efeitos dos fármacos , Neutrófilos/patologia , Ativador de Plasminogênio Tecidual/administração & dosagem , Doença Aguda , Idoso , Adesão Celular , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Infarto do Miocárdio/patologia , Reperfusão Miocárdica , Proteínas Recombinantes/administração & dosagem
18.
Arch Dis Child Fetal Neonatal Ed ; 89(4): F315-20, 2004 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-15210663

RESUMO

OBJECTIVE: To identify risk factors for the development of cystic periventricular leucomalacia (PVL) in twin gestation. DESIGN: Retrospective case-control study. SETTING: Tertiary care university hospital, Department of Paediatrics, Division of Neonatology, Graz, Austria. PATIENTS: Preterm twin gestations with one sibling having developed cystic PVL, diagnosed by ultrasound scans, compared with their co-twins without PVL, in hospital between 1988 and 2000. MAIN OUTCOME MEASURES: Perinatal and postnatal risk factors for the development of PVL. RESULTS: Eighteen preterm twin gestations were included. Monochorionicity was evident in 47% of the pregnancies, and twin to twin transfusion syndrome occurred in two cases (11%). Fetal distress correlated inversely with PVL (15% v 53%, p = 0.019, relative risk (RR) = 2.057, 95% confidence interval (CI) = 1.067 to 3.968). Hypocarbia with Pco(2) levels below 30 mm Hg (4 kPa) was diagnosed in 29% of the cases compared with 6% of the controls (p = 0.038, RR = 1.944, 95% CI = 1.113 to 3.396). There were no significant differences between groups with regard to premature rupture of the membranes, early onset infection, respiratory distress syndrome, mechanical ventilation, arterial hypotension, persistent ductus arteriosus, and hyperbilirubinaemia. Asphyxia was only evident in three controls. Three infants died and another three were lost to follow up. None of the cases compared with 62% of the controls were diagnosed as having developed normally (p < 0.001), and 14 cases (82%) compared with two controls (15%) developed cerebral palsy (p < 0.001). CONCLUSION: Hypocarbia was the only risk factor strongly associated with cystic PVL. The general outcome of the infants was poor.


Assuntos
Leucomalácia Periventricular/etiologia , Trabalho de Parto Prematuro/etiologia , Gravidez Múltipla , Adulto , Peso ao Nascer , Estudos de Casos e Controles , Feminino , Humanos , Recém-Nascido , Leucomalácia Periventricular/diagnóstico por imagem , Gravidez , Resultado da Gravidez , Segundo Trimestre da Gravidez , Terceiro Trimestre da Gravidez , Prognóstico , Análise de Regressão , Estudos Retrospectivos , Fatores de Risco , Gêmeos , Ultrassonografia Pré-Natal
19.
Early Hum Dev ; 69(1-2): 47-56, 2002 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-12324182

RESUMO

UNLABELLED: The objective of this study was to examine the cognitive, neurological and somatic developments of children who had in utero an absent or reversed end-diastolic blood flow (ARED) in the umbilical artery or an abnormal cerebroplacental ratio (ABF). METHODS: 16 children with ARED blood flow and 15 children with ABF were each matched to children with the same gestational age, appropriate for gestational age, the same sex and born within 4 months. Data were assessed at the age of 3-6 years. Children with asphyxia, neonatal infection, malformation or major surgical interventions in the neonatal period were excluded. Each child underwent a neuropediatrical examination; furthermore, a Kaufman Assessment Battery for Children, a Snijders-Oomen Intelligence Scale for Children and a Man-Drawing Test were used to evaluate cognitive development. The socioeconomic status was also assessed. RESULTS: Children in the ARED group remained lighter and had a higher frequency of microcephaly. In the Kaufman Assessment Battery for Children and the Snijders-Oomen Intelligence Scale for Young Children, cognitive development was impaired in the ARED and the ABF groups compared to the control group. The ARED and the ABF groups, however, showed no differences. The Man-Drawing Test and the Denver Development Test did not show any differences. DISCUSSION: ARED blood flow and ABF showed impaired cognitive development. The degree of impairment was the same in the ARED and the ABF groups. Long-term follow-up studies until adulthood are necessary to see if impaired cognitive development remains significant in these groups of patients.


Assuntos
Artérias Cerebrais/diagnóstico por imagem , Transtornos Cognitivos/fisiopatologia , Deficiências do Desenvolvimento/fisiopatologia , Doenças do Sistema Nervoso/fisiopatologia , Circulação Placentária , Complicações Cardiovasculares na Gravidez/fisiopatologia , Artérias Umbilicais/fisiopatologia , Adulto , Criança , Pré-Escolar , Diástole , Feminino , Feto/irrigação sanguínea , Idade Gestacional , Humanos , Fluxometria por Laser-Doppler , Masculino , Gravidez , Ultrassonografia Pré-Natal , Artérias Umbilicais/diagnóstico por imagem
20.
Carbohydr Res ; 307(1-2): 147-57, 1998 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-9658570

RESUMO

Membrane vesicles of rabbit skeletal muscle were prepared and separated by sucrose density gradient centrifugation. The fractions obtained (in the order of increasing density) were sarcolemma (SL), T-tubules (TT), sarcoplasmic reticulum (SR1 and SR2) and triads/mitochondria (Tr/M) as characterized by their specific marker enzymes, ligand binding, and ion flux activities. The distribution of neutral glycosphingolipids and gangliosides in these membrane preparations has been documented in the preceding paper (J. Müthing, U. Maurer, U. Neumann, B. Kniep, and S. Weber-Schürholz, Carbohydr, Res., (1988) 135-145). GM3(Neu5Ac) is the dominant ganglioside, neolacto-series gangliosides are moderately expressed and ganglio-series gangliosides were found in minor quantities, however, all showing different qualitative and quantitative membrane-type specific patterns. The voltage dependent Ca(2+)-channels of skeletal muscle reside prevalently in the triad enriched membrane fractions deduced from highest binding capacity of 1,4-dihydropyridines. Calcium channel complexes of triads were reconstituted into unilamellar phospholipid vesicles of 400 nm defined size and the active 45Ca(2+)-uptake into intravesicular space was measured after incorporation of muscle specific gangliosides into the outer vesicle lipid bilayer in parallel to control liposomes without gangliosides. GM3(Neu5Ac) strongly increased the uptake of 45Ca2+ (+285%) whereas GM3(Neu5Gc) severely inhibited the ion flux (-61%). Neolacto-series gangliosides evoked miscellaneous effects upon 45Ca(2+)-flux depending on isomeric sialic acid configuration, oligosaccharide size and fatty acid chain length of the ceramide portion. VI3Neu5Ac-nLcOse6Cer (C24-fatty acid), IV3Neu5Ac-nLcOse4Cer (C16-fatty acid) and IV6Neu5Ac-nLcOse4Cer (C16-fatty acid) strongly enhanced the 45Ca(2+)-flux (+208, +162, and +120%, respectively, whereas IV3Neu5Ac-nLcOse4Cer (C24-fatty acid), VI3Neu5Ac-nLcOse6Cer (C16-fatty acid) and IV6Neu5Ac-nLcOse4Cer (C24-fatty acid) slightly reduced 45Ca(2+)-flux (-3, -6, and -17%, respectively). Out of all gangliosides tested in this study, GM1 showed the strongest stimulatory effect (+327%). GD1a and GT1b gave rise to remarkable flux-stimulation of +283 and +255%, respectively, whereas GD1b exhibited only a slightly positive effect (+38%). This data suggest a functional role of gangliosides in subcellular muscle membranes giving strong evidence that gangliosides are capable of modulating the cytosolic calcium level of muscle, which regulates muscle contraction.


Assuntos
Canais de Cálcio/metabolismo , Cálcio/metabolismo , Gangliosídeos/química , Gangliosídeos/farmacologia , Membranas Intracelulares/metabolismo , Músculo Esquelético/metabolismo , Sarcolema/metabolismo , Animais , Canais de Cálcio/efeitos dos fármacos , Configuração de Carboidratos , Sequência de Carboidratos , Fracionamento Celular , Membranas Intracelulares/efeitos dos fármacos , Lipossomos , Microtúbulos/efeitos dos fármacos , Microtúbulos/metabolismo , Mitocôndrias Musculares/efeitos dos fármacos , Mitocôndrias Musculares/metabolismo , Modelos Estruturais , Dados de Sequência Molecular , Fibras Musculares Esqueléticas/metabolismo , Fibras Musculares Esqueléticas/ultraestrutura , Músculo Esquelético/ultraestrutura , Coelhos , Sarcolema/efeitos dos fármacos , Retículo Sarcoplasmático/efeitos dos fármacos , Retículo Sarcoplasmático/metabolismo
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