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1.
Hautarzt ; 69(2): 109-115, 2018 Feb.
Artigo em Alemão | MEDLINE | ID: mdl-29344728

RESUMO

BACKGROUND: Graft-versus-host disease (GvHD) is a complex multiorgan disease, which can occur as a complication following allogeneic stem cell transplantation. Involvement of the skin represents the most common appearance of GvHD. The role of the dermatologist is critical for diagnosis and initiation of treatment. OBJECTIVES: The aim of this article is to provide a comprehensive review of the cutaneous types of GvHD and to present the most recent data on diverse therapy options for its acute and chronic form allowing the clinician to establish a definite diagnosis and to initiate proper therapy. MATERIALS AND METHODS: Possible clinical appearances and recommended criteria to assist in making the right diagnosis are presented by means of expert recommendations. RESULTS AND CONCLUSION: GvHD is still a complex entity whose diagnosis is often associated with challenges due to its variable presentation. Proper diagnosis and subsequent therapy is paramount for the optimal clinical outcome.


Assuntos
Doença Enxerto-Hospedeiro/diagnóstico , Transplante de Células-Tronco Hematopoéticas/efeitos adversos , Dermatopatias/diagnóstico , Aloenxertos , Diagnóstico Diferencial , Doença Enxerto-Hospedeiro/classificação , Doença Enxerto-Hospedeiro/tratamento farmacológico , Humanos , Comunicação Interdisciplinar , Colaboração Intersetorial , Fotoferese , Dermatopatias/classificação , Dermatopatias/tratamento farmacológico
2.
J Eur Acad Dermatol Venereol ; 31(10): 1581-1594, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-28786499

RESUMO

The term 'sclerosing diseases of the skin' comprises specific dermatological entities which have fibrotic changes of the skin in common. These diseases mostly manifest in different clinical subtypes according to cutaneous and extracutaneous involvement and can sometimes be difficult to distinguish from each other. The present guideline focuses on characteristic clinical and histopathological features, diagnostic scores and the serum autoantibodies most useful for differential diagnosis. In addition, current strategies in the first- and advanced-line therapy of sclerosing skin diseases are addressed in detail. Part 2 of this guideline provides clinicians with an overview of the diagnosis and treatment of scleromyxedema, scleredema (of Buschke) and nephrogenic systemic sclerosis (nephrogenic fibrosing dermopathy).


Assuntos
Dermopatia Fibrosante Nefrogênica/diagnóstico , Dermopatia Fibrosante Nefrogênica/terapia , Escleredema do Adulto/diagnóstico , Escleredema do Adulto/terapia , Escleromixedema/diagnóstico , Escleromixedema/terapia , Diagnóstico Diferencial , Humanos , Dermopatia Fibrosante Nefrogênica/patologia , Escleredema do Adulto/patologia , Escleromixedema/patologia
3.
J Eur Acad Dermatol Venereol ; 31(9): 1401-1424, 2017 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-28792092

RESUMO

The term 'sclerosing diseases of the skin' comprises specific dermatological entities, which have fibrotic changes of the skin in common. These diseases mostly manifest in different clinical subtypes according to cutaneous and extracutaneous involvement and can sometimes be difficult to distinguish from each other. The present guideline focuses on characteristic clinical and histopathological features, diagnostic scores and the serum autoantibodies most useful for differential diagnosis. In addition, current strategies in the first- and advanced-line therapy of sclerosing skin diseases are addressed in detail. Part 1 of this guideline provides clinicians with an overview of the diagnosis and treatment of localized scleroderma (morphea), and systemic sclerosis including overlap syndromes of systemic sclerosis with diseases of the rheumatological spectrum.


Assuntos
Esclerodermia Localizada , Escleroderma Sistêmico , Doenças do Tecido Conjuntivo Indiferenciado , Humanos , Diagnóstico Diferencial , Europa (Continente) , Exame Físico , Prognóstico , Esclerodermia Localizada/diagnóstico , Esclerodermia Localizada/patologia , Esclerodermia Localizada/terapia , Escleroderma Sistêmico/diagnóstico , Escleroderma Sistêmico/patologia , Escleroderma Sistêmico/terapia , Doenças do Tecido Conjuntivo Indiferenciado/diagnóstico , Doenças do Tecido Conjuntivo Indiferenciado/patologia , Doenças do Tecido Conjuntivo Indiferenciado/terapia
4.
Hautarzt ; 66(11): 804-9, 2015 Nov.
Artigo em Alemão | MEDLINE | ID: mdl-26431837

RESUMO

Extracorporeal photopheresis (ECP) is a treatment approach that combines leukapheresis with photochemotherapy and is derived from PUVA; with this procedure, nucleated cells such as lymphocytes and monocytes are extracorporeally irradiated with UVA light after photosensitization. ECP is an effective treatment modality with few side effects that in recent years has been expanded to treat a range of indications. It has been proven effective in the treatment of cutaneous T cell lymphoma and is being increasing used in other lymphocyte-mediated, autoimmune and inflammatory diseases that are associated with proliferation of autoreactive T cells.


Assuntos
Dermatite/terapia , Fotoferese/métodos , Fotoferese/tendências , Fármacos Fotossensibilizantes/uso terapêutico , Neoplasias Cutâneas/terapia , Dermatite/patologia , Medicina Baseada em Evidências , Humanos , Neoplasias Cutâneas/patologia , Resultado do Tratamento , Raios Ultravioleta
5.
J Eur Acad Dermatol Venereol ; 28 Suppl 1: 1-37, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-24354653

RESUMO

BACKGROUND: After the first investigational study on the use of extracorporeal photopheresis for the treatment of cutaneous T-cell lymphoma was published in 1983 with its subsequent recognition by the FDA for its refractory forms, the technology has shown significant promise in the treatment of other severe and refractory conditions in a multi-disciplinary setting. Among the major studied conditions are graft versus host disease after allogeneic bone marrow transplantation, systemic sclerosis, solid organ transplant rejection and inflammatory bowel disease. MATERIALS AND METHODS: In order to provide recognized expert practical guidelines for the use of this technology for all indications the European Dermatology Forum (EDF) proceeded to address these questions in the hands of the recognized experts within and outside the field of dermatology. This was done using the recognized and approved guidelines of EDF for this task. RESULTS AND CONCLUSION: These guidelines provide at present the most comprehensive available expert recommendations for the use of extracorporeal photopheresis based on the available published literature and expert consensus opinion.


Assuntos
Doenças Autoimunes/tratamento farmacológico , Linfoma Cutâneo de Células T/tratamento farmacológico , Fotoferese/estatística & dados numéricos , Fármacos Fotossensibilizantes/uso terapêutico , Neoplasias Cutâneas/tratamento farmacológico , Rejeição de Enxerto/tratamento farmacológico , Doença Enxerto-Hospedeiro/tratamento farmacológico , Humanos , Doenças Inflamatórias Intestinais/tratamento farmacológico , Fotoferese/métodos , Escleroderma Sistêmico/tratamento farmacológico , Resultado do Tratamento
6.
Cell Death Differ ; 15(2): 398-407, 2008 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-18049480

RESUMO

Signaling mediated by activation of the transmembrane receptor Notch influences cell-fate decisions, differentiation, proliferation, and cell survival. Activated Notch reduces proliferation by altering cell-cycle kinetics and promotes differentiation in hematopoietic progenitor cells. Here, we investigated if the G(1) arrest and differentiation induced by activated mNotch1 are dependent on tumor suppressor p53, a critical mediator of cellular growth arrest. Multipotent wild-type p53-expressing (p53(wt)) and p53-deficient (p53(null)) hematopoietic progenitor cell lines (FDCP-mix) carrying an inducible mNotch1 system were used to investigate the effects of proliferation and differentiation upon mNotch1 signaling. While activated Notch reduced proliferation of p53(wt)-cells, no change was observed in p53(null)-cells. Activated Notch upregulated the p53 target p21(cip/waf) in p53(wt)-cells, but not in p53(null)-cells. Induction of the p21(cip/waf) gene by activated Notch was mediated by increased binding of p53 to p53-binding sites in the p21(cip/waf) promoter and was independent of the canonical RBP-J binding site. Re-expression of p53(wt) in p53(null) cells restored the inhibition of proliferation by activated Notch. Thus, activated Notch inhibits proliferation of multipotent hematopoietic progenitor cells via a p53-dependent pathway. In contrast, myeloid and erythroid differentiation was similarly induced in p53(wt) and p53(null) cells. These data suggest that Notch signaling triggers two distinct pathways, a p53-dependent one leading to a block in proliferation and a p53-independent one promoting differentiation.


Assuntos
Eritropoese , Células-Tronco Hematopoéticas/fisiologia , Células-Tronco Multipotentes/fisiologia , Mielopoese , Receptor Notch1/metabolismo , Proteína Supressora de Tumor p53/metabolismo , Animais , Proliferação de Células , Células-Tronco Hematopoéticas/citologia , Células-Tronco Hematopoéticas/metabolismo , Camundongos , Camundongos Mutantes , Células-Tronco Multipotentes/citologia , Células-Tronco Multipotentes/metabolismo , Transdução de Sinais
7.
Hautarzt ; 60(4): 337-43; quiz 344, 2009 Apr.
Artigo em Alemão | MEDLINE | ID: mdl-19352737

RESUMO

Photopheresis, originally developed in dermatology, has become a treatment method accepted across various disciplines. A basic knowledge of photomedicine and photobiology is one of the cornerstones of dermatology. Even if photopheresis is used for indications that are not specifically dermatological, e.g. graft-versus-host disease or Crohn's disease, an experienced dermatologist trained in the use of photopheresis should therefore always be consulted.


Assuntos
Dermatologia/instrumentação , Dermatologia/métodos , Fotoferese/instrumentação , Fotoferese/métodos , Dermatopatias/terapia , Dermatologia/tendências , Alemanha , Humanos , Fotoferese/tendências
8.
Mol Cell Biol ; 9(12): 5746-9, 1989 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-2586530

RESUMO

At least two separate but interdependent events are required to attain autonomous growth as a consequence of ectopic expression of the multilineage colony-stimulating factor gene in hematopoietic progenitor cells. The rate at which the second event occurs is more than 3 orders of magnitude higher in precursor cell lines (FDC-P1 or FDC-P2) than in stem cell lines (FDC-Pmix). Autonomous, but not density-dependent, growth is tightly coupled to tumorigenicity in precursor cells; however, neither growth-factor-independent nor autonomously growing stem cell lines are tumorigenic.


Assuntos
Transformação Celular Neoplásica , Fatores Estimuladores de Colônias/genética , Expressão Gênica , Células-Tronco Hematopoéticas/citologia , Mutação , Animais , Divisão Celular/efeitos dos fármacos , Linhagem Celular , Fatores Estimuladores de Colônias/imunologia , Fatores Estimuladores de Colônias/farmacologia , Vetores Genéticos , Células-Tronco Hematopoéticas/metabolismo , Soros Imunes , Cinética , Camundongos
9.
Oncogene ; 12(4): 931-5, 1996 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-8632916

RESUMO

Differentiation of blood cells is paralleled by a timely ordered expression of cytokine receptor genes. We show here that the expression of the c-fms gene which encodes the lineage-specific receptor for macrophage colony-stimulating factor (M-CSF or CSF-1) is directly linked to ligand-mediated activation of the receptor for the granulocyte/macrophage colony-stimulating factor (GM-CSF). In interleukin-3 (IL-3) dependent multipotent progenitor cells, FDC-Pmix GMV#2 cells, GM-CSF treatment results in the rapid formation of full-length c-fms transcripts. Surprisingly, this upregulation of c-fms transcripts is also observed in mouse NIH3T3 fibroblasts stably transfected with genes coding for the alpha- and beta-subunits of the GM-CSF receptor. These results indicate a direct control by the GM-CSF receptor that takes place regardless of cell differentiation. Furthermore, a 2.1 kb genomic fragment containing the c-fms proximal promoter directs GM-CSF-inducible expression of a reporter gene, suggesting a regulation of c-fms gene expression on the transcriptional level.


Assuntos
Regulação da Expressão Gênica/efeitos dos fármacos , Genes fms , Fator Estimulador de Colônias de Granulócitos e Macrófagos/farmacologia , Células-Tronco Hematopoéticas/citologia , Células-Tronco Hematopoéticas/metabolismo , Receptor de Fator Estimulador de Colônias de Macrófagos/biossíntese , Transcrição Gênica , Células 3T3 , Animais , Diferenciação Celular , Linhagem Celular , Granulócitos/citologia , Células-Tronco Hematopoéticas/efeitos dos fármacos , Interleucina-3/farmacologia , Cinética , Macrófagos/citologia , Camundongos , Regiões Promotoras Genéticas , Receptores de Fator Estimulador das Colônias de Granulócitos e Macrófagos/biossíntese , Receptores de Fator Estimulador das Colônias de Granulócitos e Macrófagos/metabolismo , Proteínas Recombinantes/biossíntese , Proteínas Recombinantes/metabolismo , Transcrição Gênica/efeitos dos fármacos , Transfecção
10.
Curr Top Microbiol Immunol ; 251: 27-34, 2000.
Artigo em Inglês | MEDLINE | ID: mdl-11036755

RESUMO

The genes controlling self renewal in the haemopoietic system are still unknown. Using retroviral insertional mutagenesis we have established multipotent haemopoietic stem cell lines (FDCP-mix) that possess an increased self renewal capacity in vitro. To identify genes involved in the regulation of self renewal, proviral integration sites were cloned from FDCP-mix cells and used as probes to screen independently isolated FDCP-mix cell lines for a common proviral insertion site. So far, two common integration sites have been identified, A25 and M4. A25 is rearranged in 50% of the FDCP-mix cell lines and M4 in 10%. Genes located at or near these sites are likely candidates for the control of self renewal of haemopoietic stem cells.


Assuntos
Diferenciação Celular/genética , Células-Tronco Hematopoéticas/citologia , Mutagênese Insercional , Técnicas de Cultura/métodos , Vírus Auxiliares , Retroviridae , Integração Viral/genética
11.
Leukemia ; 11(10): 1753-61, 1997 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-9324297

RESUMO

A coculture system of a murine erythroblastic leukemia cell line (ELM-D) with its supportive stromal cell line (MS-5) was established. Long-term growth of ELM-D cells is strictly stroma cell dependent. Interaction between stem cell factor (SCF) and its receptor, c-kit, was demonstrated to be important for stroma cell-dependent growth by anti c-kit neutralizing monoclonal antibody (mAb) inhibition experiments. Significantly, soluble growth factors such as granulocyte-macrophage colony-stimulating factor (GM-CSF), interleukin-3 (IL-3) or SCF of MS-5 stromal cells (MS-5 CM) could replace the requirement of stroma cells for a considerable period. However, ELM-D cells maintained in these growth factors underwent clonal extinction after 3-6 weeks unless contact with stroma was re-established. Furthermore, IL-3 or GM-CSF acted in a dominant manner in inducing cell death in the presence of stroma cells. Cells showing clonal extinction undergo programmed cell death and do not differentiate. These altered growth properties of ELM-D cells exposed to soluble growth factors or to stroma cells appear to be analogous to those described for T or B cells primed by antigen presenting cells and then grown in growth factors.


Assuntos
Substâncias de Crescimento/fisiologia , Leucemia Eritroblástica Aguda/patologia , Animais , Divisão Celular/efeitos dos fármacos , Células Clonais , Meios de Cultura , Fator Estimulador de Colônias de Granulócitos e Macrófagos/farmacologia , Interleucina-3/farmacologia , Camundongos , Proteínas Proto-Oncogênicas c-kit/efeitos dos fármacos , Proteínas Proto-Oncogênicas c-kit/metabolismo , RNA Mensageiro/metabolismo , Solubilidade , Células Estromais/patologia
12.
Exp Hematol ; 28(11): 1206-13, 2000 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-11063868

RESUMO

Notch receptors are involved in the regulation of cell-fate decisions, differentiation, and proliferation in many tissues. The expression of Notch receptors on hemopoietic cells and of cognate ligands on bone marrow stromal cells suggests a possible role for Notch signaling in the regulation of hemopoiesis. We were interested to assess the involvement of Notch1 signaling on cell proliferation of myeloid progenitor cells. Proliferation, cell-cycle status, and apoptosis of myeloid progenitor 32D cell lines engineered to permit the conditional induction of the constitutively active intracellular domain of mNotch1 (mN1(IC)) by the 4-hydroxytamoxifen(OHT)-inducible system were analyzed in the presence or absence of OHT. The induction of mN1(IC) by OHT resulted in reduction of proliferation (p<0.01) and accumulation of cells in the G(1)/G(0) phase of the cell cycle (p<0.001) without substantially affecting apoptosis of 32D cells. These effects were observed under culture conditions that allow differentiation and, to a lesser degree, under conditions that normally promote self-renewal in the absence of differentiated cells. Our data suggest that mNotch1 signaling suppresses proliferation of myeloid progenitor cells by altering cell-cycle kinetics.


Assuntos
Ciclo Celular/fisiologia , Leucopoese , Proteínas de Membrana/fisiologia , Células Progenitoras Mieloides/citologia , Células Progenitoras Mieloides/fisiologia , Divisão Celular/fisiologia , Linhagem Celular , Humanos , Receptores de Superfície Celular/fisiologia , Receptores Notch , Transdução de Sinais/fisiologia
13.
Exp Hematol ; 22(9): 933-40, 1994 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-8062891

RESUMO

FDCP-Mix cells infected with a retroviral vector expressing the GM-CSF gene (GMV-FDCP-Mix) self-renew in the presence of interleukin-3 (IL-3), are multipotent, and undergo differentiation into granulocytes and macrophages coupled with clonal extinction after removal of IL-3. Mutants of GMV-FDCP-Mix were isolated that escape clonal extinction after differentiation induction by the autocrine secreted GM-CSF. Some of these mutant clones have a blast cell morphology and are blocked in differentiation, whereas others exhibit all stages of granulocyte and macrophage differentiation without clonal extinction. In contrast to the parental GMV-FDCP-Mix cells, all the mutants tested were leukemogenic when injected into syngeneic mice. Depending on the in vitro differentiation capacity of the transplanted mutant cell lines, the animals developed undifferentiated blast cell leukemias or CML-like syndromes. Thus, these mutant cell lines can be used to define the cooperating steps in autocrine myeloid leukemia.


Assuntos
Transformação Celular Neoplásica/patologia , Fator Estimulador de Colônias de Granulócitos e Macrófagos/fisiologia , Células-Tronco Hematopoéticas/citologia , Leucemia Mielogênica Crônica BCR-ABL Positiva/etiologia , Leucemia Mielogênica Crônica BCR-ABL Positiva/patologia , Mutação , Animais , Diferenciação Celular/efeitos dos fármacos , Diferenciação Celular/fisiologia , Linhagem Celular , DNA de Neoplasias/análise , DNA de Neoplasias/genética , Regulação da Expressão Gênica , Fator Estimulador de Colônias de Granulócitos e Macrófagos/genética , Granulócitos/citologia , Granulócitos/efeitos dos fármacos , Granulócitos/fisiologia , Hematopoese/fisiologia , Células-Tronco Hematopoéticas/efeitos dos fármacos , Células-Tronco Hematopoéticas/fisiologia , Interleucina-3/farmacologia , Macrófagos/citologia , Macrófagos/efeitos dos fármacos , Macrófagos/fisiologia , Camundongos
14.
Hum Gene Ther ; 2(1): 61-70, 1991.
Artigo em Inglês | MEDLINE | ID: mdl-1863641

RESUMO

Retroviral vectors are considered to be the most suited vehicles for somatic gene therapy with hematopoietic stem cells as targets. Retrovirus-mediated gene transfer into differentiation-restricted hematopoietic precursor (FDC-P1, FDC-P2) and multipotent progenitor (stem) cell lines (FDC-Pmix) is inefficient. Two cellular restrictions are involved. One is specific for stem but not precursor cells and is at the level of transcription. Due to a unique property of the transcriptional control region of the myeloproliferative sarcoma virus (MPSV), vectors derived from MPSV are not affected by this block. The second restriction occurs before proviral DNA synthesis and integration. This inhibition of effective viral infection depends on the state of differentiation, being more pronounced in multipotent clonogenic blast cells. This block to retroviral infection affects all retroviral vectors tested.


Assuntos
Vírus Defeituosos/genética , Regulação da Expressão Gênica , Vetores Genéticos , Células-Tronco Hematopoéticas/microbiologia , Vírus do Sarcoma Murino de Moloney/genética , Transfecção , Animais , Diferenciação Celular , Linhagem Celular , DNA Viral/genética , Vírus Defeituosos/fisiologia , Fibroblastos/metabolismo , Células-Tronco Hematopoéticas/citologia , Camundongos , Vírus do Sarcoma Murino de Moloney/fisiologia , Provírus/genética , Provírus/metabolismo , Receptores Virais/metabolismo , Transcrição Gênica , Transformação Genética
15.
Bone Marrow Transplant ; 18(3): 513-9, 1996 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-8879611

RESUMO

Peripheral blood progenitor cells (PBPCs) obtained from cytapheresis products (CPs) of tumor patients undergoing mobilizing chemotherapy for PBPC support and dose-intensified anticancer chemotherapy initiate multilineage human hematopoiesis after intraperitoneal (i.p.) transplantation into young severe combined immunodeficient (SCID) mice. The engraftment process was significantly accelerated by subcutaneous cotransplants of a rat fibroblast cell line stably transfected with a retroviral vector carrying the human interleukin-3 (hIL-3) gene and producing sustained in vivo levels of circulating human IL-3 over a prolonged period of time. These cotransplants were found to provide a suitable microenvironment for i.p. transplanted CD34-positive cells separated from PBPC preparations using immunomagnetic beads. Flow cytometry analysis and immunocytology revealed that selected PB CD34- cells, more than 90% pure, were capable of initiating and sustaining a productive multilineage hematopoiesis preferentially within the hIL-3-secreting cotransplants followed by release of mature human cells into the circulation, spleen and thymus. The percentages of human cells found in hIL-3 cotransplants 8 weeks post-transplantation (p.t.) were generally higher than those measured after transplantation of complete CP mononuclear cells containing comparable doses of CD34-positive cells. When selected PB CD34+ cells that were expanded ex vivo with combinations of human hematopoietic growth factors including the c-kit ligand (KL), interleukin (IL)-1 beta, IL-3, IL-6, erythropoietin (EPO) and granulocyte-macrophage colony-stimulating factor (GM-CSF) for 14 days were grafted to cotransplant-carrying SCID mice, a considerable loss of their proliferative potential was observed regardless of the HGF combination used. When experiments with grafts of selected PBPC were compared to those performed with selected/expanded PBPC on a per CD34+ cell basis the results revealed that over a dose range of 0.3 to 1.0 x 10(6) cells/graft the in vivo proliferative capacity of expanded cells was reduced by a factor of 2 to 3.


Assuntos
Antígenos CD34/análise , Hematopoese , Transplante de Células-Tronco Hematopoéticas , Interleucina-3/genética , Animais , Divisão Celular , Linhagem Celular , Fibroblastos/metabolismo , Humanos , Camundongos , Camundongos SCID , Ratos , Transfecção , Transplante Heterólogo
16.
Phytochemistry ; 49(1): 153-6, 1998 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-9745766

RESUMO

The cytotoxic compound, virgaureasaponin 1, was converted using several optimized enzymecatalysed hydrolyses to the 28-O-beta-D-xylopyranosyl (1-->4)-alpha-L-rhamnopyranosyl-(1-->2)-beta-D-fucopyranoside (2), and the 28-O-alpha-L-rhamnopyranosyl-(1-->3)-beta-D-xylopyranosyl-(1-->4)-alpha- L- rhamnopyranosyl-(1-->2)-beta-D-fucopyranoside (3) and 28-O-beta-D-xylyopyranosyl-(1-->4)-alpha-L-rhamnopyranosyl-(1-->2) - beta-D-fucopyranoside (4) both lacking the glucose moiety at C-3 of the aglycone. The terminal rhamnose of the acylglycosidic bonded tetrasaccharide was cleaved by naringinase to give compound 2. The new acylglycosides 3 and 4 were obtained with the help of a relatively crude beta-glucuronidase preparation, but the cleavage of the sapogenin bonded glucose was impossible using several beta-glucosidase preparations directly. These derivatives were used for the investigation of the relationship between the saponin carbohydrate structure and their cytotoxic activity.


Assuntos
Antineoplásicos Fitogênicos/química , Glicosídeo Hidrolases/metabolismo , Complexos Multienzimáticos/metabolismo , Saponinas/química , Triterpenos/química , beta-Glucosidase/metabolismo , Animais , Antineoplásicos Fitogênicos/isolamento & purificação , Antineoplásicos Fitogênicos/toxicidade , Configuração de Carboidratos , Sequência de Carboidratos , Sobrevivência Celular/efeitos dos fármacos , Hidrólise , Camundongos , Modelos Moleculares , Dados de Sequência Molecular , Penicillium/enzimologia , Saponinas/isolamento & purificação , Saponinas/toxicidade , Triterpenos/isolamento & purificação , Triterpenos/toxicidade , Células Tumorais Cultivadas
17.
J Biochem Biophys Methods ; 43(1-3): 209-21, 2000 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-10869677

RESUMO

Polydimethylsiloxanes (PDMSs) modified by introducing ethylene oxide units with the aim of forming sufficiently water-soluble siloxane compounds were characterized using supercritical fluid chromatography (SFC) coupled with Fourier transform infrared (FTIR) spectroscopy and atmospheric pressure chemical ionization mass spectrometry (APCI-MS), and matrix-assisted laser desorption-ionization time-of-flight mass spectrometry (MALDI-TOF-MS). SFC has a domain in analyzing oligomers. Hyphenated techniques enable elucidation of the components. Remarkable is the resolution and short analysis time of MALDI-TOF-MS. SFC also allows quantification of the basic and reaction products.


Assuntos
Cromatografia/instrumentação , Cromatografia/métodos , Dimetilpolisiloxanos/isolamento & purificação , Espectrometria de Massas/métodos , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz/métodos , Modelos Químicos , Polímeros/isolamento & purificação , Espectrofotometria Infravermelho/métodos , Fatores de Tempo
18.
Cell Death Differ ; 19(3): 461-9, 2012 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-21869831

RESUMO

Notch signaling is involved in several cell lineage determination processes during embryonic development. Recently, we have shown that Sox9 is most likely a primary target gene of Notch1 signaling in embryonic stem cells (ESCs). By using our in vitro differentiation protocol for chondrogenesis from ESCs through embryoid bodies (EBs) together with our tamoxifen-inducible system to activate Notch1, we analyzed the function of Notch signaling and its induction of Sox9 during EB differentiation towards the chondrogenic lineage. Temporary activation of Notch1 during early stages of EB, when lineage determination occurs, was accompanied by rapid and transient Sox9 upregulation and resulted in induction of chondrogenic differentiation during later stages of EB cultivation. Using siRNA targeting Sox9, we knocked down and adjusted this early Notch1-induced Sox9 expression peak to non-induced levels, which led to reversion of Notch1-induced chondrogenic differentiation. In contrast, continuous Notch1 activation during EB cultivation resulted in complete inhibition of chondrogenic differentiation. Furthermore, a reduction and delay of cardiac differentiation observed in EBs after early Notch1 activation was not reversed by siRNA-mediated Sox9 knockdown. Our data indicate that Notch1 signaling has an important role during early stages of chondrogenic lineage determination by regulation of Sox9 expression.


Assuntos
Diferenciação Celular/fisiologia , Condrogênese/fisiologia , Células-Tronco Embrionárias/metabolismo , Receptor Notch1/metabolismo , Fatores de Transcrição SOX9/metabolismo , Transdução de Sinais/fisiologia , Animais , Diferenciação Celular/efeitos dos fármacos , Linhagem Celular , Condrogênese/efeitos dos fármacos , Células-Tronco Embrionárias/citologia , Antagonistas de Estrogênios/farmacologia , Técnicas de Silenciamento de Genes , Humanos , Camundongos , Receptor Notch1/genética , Fatores de Transcrição SOX9/genética , Transdução de Sinais/efeitos dos fármacos , Tamoxifeno/farmacologia
19.
Leukemia ; 26(4): 746-56, 2012 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-21926960

RESUMO

Chronic graft-versus-host disease (GVHD) remains a serious complication after allogeneic hematopoietic stem cell transplantation (HCT). In 2005 the National Institutes of Health (NIH) established new criteria for chronic GVHD based on retrospective data and expert recommendations. We prospectively evaluated the incidence of NIH-defined chronic GVHD and its prognostic impact in 178 consecutive patients. The cumulative incidence of chronic GVHD at 3 years was 64, 48 and 16% for chronic classic GVHD and overlap syndrome. Prior acute GVHD and myeloablative conditioning were significantly associated with increased risk of chronic GVHD. Three-year survival (overall survival (OS)) for late-acute GVHD, chronic classic and overlap chronic GVHD when assigned on day 100 were 69, 83 and 73%. OS was significantly worse for patients with platelet counts below 100 g/l at onset of chronic GVHD (35% versus 86%, P<0.0001) and progressive as compared with de novo and quiescent onset of chronic GVHD (54.5% versus 89.5% versus 84%, P = 0.022 and 0.001). Peak severity of chronic GVHD had no impact on non-relapse mortality (NRM) and OS. Recurrent acute GVHD, platelet counts below 100 g/l at diagnosis of chronic GVHD, progressive onset of chronic GVHD and advanced disease stage prior to HCT were significantly associated with increased NRM. This prospective analysis provides for the first-time data on the incidence rates of NIH-defined chronic GVHD categories and identified risk factors for the occurrence of chronic GVHD. A prognostic value of thrombocytopenia and progressive onset type of chronic GVHD for survival after HCT was observed in NIH-defined chronic GVHD.


Assuntos
Doença Enxerto-Hospedeiro/mortalidade , Trombocitopenia/mortalidade , Adulto , Idoso , Doença Crônica , Progressão da Doença , Feminino , Doença Enxerto-Hospedeiro/epidemiologia , Humanos , Incidência , Masculino , Pessoa de Meia-Idade , Modelos de Riscos Proporcionais , Estudos Prospectivos , Fatores de Risco , Índice de Gravidade de Doença
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