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1.
HLA ; 2018 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-29943500

RESUMO

Natural killer cells are thought to influence the outcome of hematopoietic stem cell transplant (HSCT), impacting on relapse, overall survival, graft versus host disease and the control of infection, in part through the complex interplay between the large and genetically diverse killer immunoglobulin-like receptor (KIR) family and their ligands. This study examined the relationship between KIR gene content and clinical outcomes including the control of opportunistic infections such as cytomegalovirus in the setting of human leucocyte antigen (HLA)-matched sibling HSCT in an Australian cohort. The presence of the KIR B haplotype which contain more activating receptors in the donor, in particular centromeric B haplotype genes (Cen-B), was associated with improved overall survival of patients with acute myeloid leukemia (AML) undergoing sibling HSCT and receiving myeloablative conditioning. Donor Cen-B haplotype was also associated with reduced acute graft versus host disease grades II-IV whereas donor telomeric-B haplotype was associated with decreased incidence of CMV reactivation. In contrast, we were not able to demonstrate a reduced rate of relapse when the donor had KIR Cen-B, however relapse with a donor Cen-A haplotype was a competing risk factor to poor overall survival. Here we show that the presence of donor activating KIR led to improved outcome for the patient, potentially through reduced relapse rates and decreased incidence of acute GvHD translating to improved overall survival. This article is protected by copyright. All rights reserved.

6.
Int J Cell Biol ; 2013: 918242, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23997768

RESUMO

With the increasing relevance of cell-based therapies, there is a demand for cell-labeling techniques for in vitro and in vivo studies. For the reasonable tracking of transplanted stem cells in animal models, the usage of quantum dots (QDs) for sensitive cellular imaging has major advances. QDs could be delivered to the cytoplasm of the cells providing intense and stable fluorescence. Although QDs are emerging as favourable nanoparticles for bioimaging, substantial investigations are still required to consider their application for adult stem cells. Therefore, rat pancreatic stem cells (PSCs) were labeled with different concentrations of CdSe quantum dots (Qtracker 605 nanocrystals). The QD labeled PSCs showed normal proliferation and their usual spontaneous differentiation potential in vitro. The labeling of the cell population was concentration dependent, with increasing cell load from 5 nM QDs to 20 nM QDs. With time-lapse microscopy, we observed that the transmission of the QD particles during cell divisions was random, appearing as equal or unequal transmission to daughter cells. We report here that QDs offered an efficient and nontoxic way to label pancreatic stem cells without genetic modifications. In summary, QD nanocrystals are a promising tool for stem cell labeling and facilitate tracking of transplanted cells in animal models.

8.
Eur Surg Res ; 49(2): 88-98, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22948659

RESUMO

BACKGROUND: Pancreatic cancer is one of the most deadly malignancies with insufficient therapeutic options and poor outcome. Cancer stem cells (CSCs) are thought to be responsible for progression and therapy resistance. We investigated the potential of pancreatic cell lines for CSC research by analyzing to what extent they contain CSC populations and how representative these are compared to clinical tissue. METHODS: Six pancreatic cancer cell lines were analyzed by flow cytometry for CD326, CD133, CD44, CD24, CXCR4 and ABCG2. Subsequently, 70 primary pancreatic tissues were evaluated for CD326, CD133 and CD44 by immunohistochemistry. RESULTS: All the cell lines but one showed a stable expression pattern throughout biological replicates. Marker expression in clinical tissue of CD44 distinguished normal patients from pancreatic carcinoma patients with a sensitivity of 50% at 80% specificity and metastasized from nonmetastasized carcinomas with 69% sensitivity at 100% specificity. CONCLUSIONS: Our results indicate a link between elevated CD44 expression, malignancy and metastasis of pancreatic tissue. Furthermore, individual pancreatic cell lines show a substantial amount of cells with CSC properties which is comparable with interpatient variability detected in primary tissue. These pancreatic cancer cell lines could thus serve for urgently needed pharmacological CSC in vitro research.


Assuntos
Biomarcadores Tumorais/metabolismo , Carcinoma/metabolismo , Linhagem Celular Tumoral/metabolismo , Células-Tronco Neoplásicas/metabolismo , Neoplasias Pancreáticas/metabolismo , Idoso , Idoso de 80 Anos ou mais , Carcinoma/patologia , Estudos de Casos e Controles , Feminino , Citometria de Fluxo , Humanos , Masculino , Pessoa de Meia-Idade , Pâncreas/patologia , Neoplasias Pancreáticas/patologia
9.
Br J Dermatol ; 162(2): 380-3, 2010 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-19772523

RESUMO

BACKGROUND: We have recently shown that the expression of nestin, a progenitor/stem cell marker protein, is localized in different mesenchymal compartments in human skin including the sweat gland stroma. OBJECTIVES: As other exocrine glands are recognized sources of multipotent stem cell populations with potential for multilineage differentiation, it was our aim to isolate, expand and characterize glandular stem cells from human sweat glands. METHODS: Isolation of human sweat glands was based on mechanical and enzymatic digestion of axillary skin. Cultivation was performed on collagen-coated cell culture dishes and the resulting cell population was investigated at the protein and mRNA level. RESULTS: Outgrowing cells of isolated sweat glands showed a high-proliferation activity and were characterized by nestin expression in more than 80% of the cells. These sweat gland stem cells could be maintained in culture for long periods of time and showed spontaneous differentiation into cells representative of the different germ layers. CONCLUSIONS: This pilot study provides the first, simple protocol for the isolation of adult human nestin-positive stem cells from the sweat gland mesenchyme, which promises to provide an easily accessible and abundantly available, autologous source of multipotent stem cells for cell-based regenerative medicine applications.


Assuntos
Células-Tronco Adultas/citologia , Proteínas de Filamentos Intermediários/metabolismo , Células-Tronco Multipotentes/metabolismo , Proteínas do Tecido Nervoso/metabolismo , Glândulas Sudoríparas/citologia , Adulto , Células-Tronco Adultas/metabolismo , Biomarcadores/metabolismo , Técnicas de Cultura de Células/métodos , Separação Celular/métodos , Células Cultivadas/metabolismo , Humanos , Proteínas de Filamentos Intermediários/genética , Células-Tronco Multipotentes/citologia , Proteínas do Tecido Nervoso/genética , Nestina , Fenótipo , Projetos Piloto , Glândulas Sudoríparas/metabolismo
11.
Ann Anat ; 191(1): 94-103, 2009 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-19054657

RESUMO

Adult stem cells may possess great plasticity, but the cellular mechanisms regulating their fate are not fully understood. Prior to application of stem cell populations in regenerative medicine, major challenges remain to be overcome. Fundamental questions about in vitro growth and spontaneous differentiation of adult stem cell populations must be resolved. In this study, we comprehensively characterized a stem cell population derived from human pancreatic tissue by analyzing mRNA and protein expression in consecutive passages. We examined transcription and protein expression levels of markers related to stem cells or differentiated cells, respectively, as well as the growth rate of a primary human pancreatic stem cell population. In particular, the course of spontaneous mRNA and protein expression of the genes for alpha-smooth muscle actin (alpha-SMA), neurofilaments (NF), cytokeratin 18 (CK18) and nestin was examined during 11 passages by means of RT-PCR and immunocytochemistry. The cell population showed exponential growth over 10 of the 11 examined passages. Both the spontaneous expression of stem cell-related mRNA and protein as well as the characteristics of spontaneous differentiation were variable. Changes in mRNA and protein expression showed no direct correlation. These results demonstrate the unpredictable behaviour of spontaneously differentiating stem cells, being influenced by numerous, barely traceable extrinsic factors. Characterization studies of stem cell populations therefore require improved analysis techniques together with strictly controlled cell cultivation conditions to improve global gene and protein expression analyses.


Assuntos
Pâncreas/citologia , Células-Tronco/citologia , Células-Tronco/fisiologia , Técnicas de Cultura de Células , Divisão Celular , DNA/genética , DNA Complementar/genética , Regulação da Expressão Gênica , Marcadores Genéticos , Humanos , Imuno-Histoquímica , Proteínas/genética , RNA Mensageiro/genética , Transcrição Gênica
12.
Transplant Proc ; 40(2): 470-2, 2008 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-18374105

RESUMO

The aim of this work was to evaluate the effects of rapamycin on rat macrophage viability and chemotaxis toward allogereic pancreatic islet supernates. Macrophages were isolated from rats by peritoneal lavage at 3 days after intraperitoneal injection of thioglycolate. Macrophage viability was studied after 7 days of culture by Cell Titer assays in the presence of rapamycin at 0.1, 1, and 10 ng/mL (n = 6). After 48 hours of culture, pancreatic rat islet supernates were studied for there chemotactic properties toward freshly isolated macrophages in the presence of rapamycin at 0.1, 1, and 10 ng/mL. Chemotaxis was expressed as a migration index defined as the number of macrophages attracted by the test solution (islet supernate +/- rapamycin)/number of macrophages attracted by the supernate (n = 6). After 3 days of culture, macrophage viability decreased significantly by 22%, 36%, and 32% in the presence of 0.1, 1, and 10 ng/mL rapamycin, respectively (P = .008). Macrophage viability remained stable at about 70% after 7 days of culture. In the presence of islet supernates, macrophage migration increased two-fold compared with those obtained by culture medium. Rapamycin did not influence macrophage migration toward culture medium. However, the drug significantly reduced the migration of macrophages toward islet supernates from 2 +/- 0.6 to 0.9 +/- 0.4, 0.7 +/- 0.3, or 0.8 +/- 0.4 in the presence of 0.1, 1, or 10 ng/mL rapamycin, respectively (P = .04). Rapamycin decreased the survival of cultured rat macrophages and their migration toward allogenic islet supernates. These results suggested that, besides its anti-proliferative effect on T cells, rapamycin reduced macrophage attraction to the graft site.


Assuntos
Sobrevivência Celular/efeitos dos fármacos , Quimiotaxia/fisiologia , Transplante das Ilhotas Pancreáticas/fisiologia , Macrófagos Peritoneais/citologia , Macrófagos Peritoneais/fisiologia , Sirolimo/farmacologia , Animais , Movimento Celular/efeitos dos fármacos , Movimento Celular/fisiologia , Quimiotaxia/efeitos dos fármacos , Meios de Cultura , Macrófagos Peritoneais/efeitos dos fármacos , Masculino , Ratos , Ratos Wistar , Transplante Homólogo
13.
Biophys J ; 94(12): 4688-99, 2008 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-18326643

RESUMO

As the main difference between bacterial and mammalian cell membranes is their net charge, the focal point of consideration in many model membrane experiments with antimicrobial peptides is lipid headgroup charge. We studied the interaction of the human multifunctional peptide LL-37 with single phospholipid monolayers, bilayers, and bilayers composed of binary mixtures of the four phospholipid species predominantly used in model membrane experiments (phosphatidylcholine, phosphatidylethanolamine, phosphatidylglycerol, and phosphatidylserine). We found that 1), the effects on single lipid monolayers are not comparable to those on the corresponding bilayers; 2), there are four different effects of LL-37 on bilayers of the four lipids; 3), the preference of LL-37 for the specific lipids is roughly inversely related to chain packing density; and 4), in the binary lipid mixtures, one lipid-and not necessarily the charged one--generally governs the mode of lipid/peptide interaction. Thus, our results show that lipid net charge is not the decisive factor determining the membrane-perturbing mechanism of LL-37, but only one of several parameters, among them packing density, the ability to form intermolecular H-bonds, and lipid molecular shape, which emphasizes how profoundly the choice of the model system can influence the outcome of a study of lipid/peptide interaction.


Assuntos
Bicamadas Lipídicas/química , Lipossomos/química , Lipídeos de Membrana/química , Modelos Químicos , Modelos Moleculares , Simulação por Computador , Conformação Molecular
14.
Clin Pharmacol Ther ; 84(4): 513-6, 2008 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-19238657

RESUMO

The irrational prescribing of drugs seems to be a general problem in medical practice, occasionally leading to serious consequences. In order to improve the drug prescribing performance of medical students, a compulsory context-learning pharmacotherapy module was implemented in 1998 in the medical curriculum of 2nd-4th-year medical students at theVU University Medical Center (VUmc), Amsterdam, The Netherlands. As part of this program, preclinical medical students are taught how to select, prescribe, and evaluate a drug regimen rationally. The aim of this study was to investigate the effect of this preclinical pharmacotherapy program on the quality of rational prescribing during the ensuing clinical clerkship of these students in internal medicine. The results of this study indicate that preclinical context-learning in pharmacotherapy leads to the use of more rational prescribing modalities by medical students during their ensuing clinical clerkship in internal medicine. This effect was obtained not only with respect to the clinical topics in which training had been given as part of the pharmacotherapy curriculum, but also for other disease situations that the students dealt with. This implies that students not only remember the specific information they have learned during the training, but are also able to apply the acquired skills in new situations (transfer effect).


Assuntos
Estágio Clínico , Competência Clínica , Prescrições de Medicamentos , Medicina Interna/educação , Farmacologia Clínica/educação , Estudantes de Medicina , Adulto , Tomada de Decisões , Educação de Graduação em Medicina , Avaliação Educacional , Humanos , Países Baixos , Aprendizagem Baseada em Problemas , Avaliação de Programas e Projetos de Saúde
15.
Mol Hum Reprod ; 13(1): 11-20, 2007 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-17114208

RESUMO

Adult pancreatic stem cells (PSCs) are able to differentiate spontaneously in vitro into various somatic cell types. Stem cells isolated from rat pancreas show extensive self-renewal ability and grow in highly viable long-term cultures. Additionally, these cells express typical stem cell markers such as Oct-4, nestin and SSEA-1. Although differentiation potential is slightly decreasing in long-term cultures, it is possible to keep cell lines up to passage 140. Clonal cell lines could be established from different passages and showed similar characteristics. Remarkably, one clonal cell line, generated from passage 75, showed deviant properties during further culture. Clonal cells formed aggregates, which built tissue-like structures in suspension culture. These generated 3D aggregates produced permanently new cells at the outside margin. Released cells had remarkable size, and closer examination by light microscopy analysis revealed oocyte-like morphology. A comparison of the gene expression patterns between primary cultures of passages 8 and 75, the clonal cell line and the produced oocyte-like cells (OLCs) from tissue-like structures demonstrated some differences. Expression of various germ cell markers, such as Vasa, growth differentiation marker 9 and SSEA-1, increased in the clonal cell line, and OLCs showed additionally expression of meiosis-specific markers SCP3 and DMC1. We here present a first pilot study investigating the putative germ line potential of adult PSCs.


Assuntos
Oócitos/citologia , Pâncreas/citologia , Células-Tronco/citologia , Animais , Biomarcadores/metabolismo , Linhagem Celular , Células Clonais , Feminino , Expressão Gênica , Masculino , Modelos Biológicos , Oócitos/metabolismo , Ratos , Ratos Sprague-Dawley , Células-Tronco/metabolismo
18.
HIV Med ; 7(3): 146-55, 2006 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-16494628

RESUMO

Objectives Current research is unclear about the most effective pharmacological agents for managing the loss of weight and fat-free mass common in HIV/AIDS. The aim of this study was to compare nandrolone decanoate with placebo and testosterone. Methods The study was a multicentre randomized double-blind placebo-controlled trial. Three hundred and three adult HIV-positive male patients with a weight loss of 5-15% in the last 12 months, or a body mass index of 17-19 kg/m(2), or a body cell mass/height ratio lower than 13.5 kg/m, were randomly assigned to receive nandrolone decanoate (150 mg), testosterone (250 mg) or placebo intramuscularly every 2 weeks for 12 weeks. Fat-free mass, weight, immune markers and perception of treatment were the main outcome measures. Results Treatment with nandrolone resulted in significantly greater increases in fat-free mass [mean increase 1.34 kg; 95% confidence interval (CI) 0.60; 2.08 kg] and in weight (mean increase 1.48 kg; 95% CI 0.82; 2.14 kg) compared with placebo. The mean increase in weight with nandrolone of 1.00 kg (95% CI 0.27; 1.74 kg) when compared with testosterone was significant, although the difference in fat free mass did not reach significance (mean increase 0.69 kg; 95% CI-0.13; 1.51 kg). Patient perception of benefit was significantly greater in the nandrolone group when compared with both the placebo and the testosterone groups. Conclusions Treatment with nandrolone decanoate increased body weight when compared with placebo and testosterone. Nandrolone decanoate treatment resulted in greater increases in fat-free mass than placebo and demonstrated a trend for a significant increase when compared with testosterone.


Assuntos
Anabolizantes/uso terapêutico , Síndrome de Emaciação por Infecção pelo HIV/tratamento farmacológico , HIV-1 , Nandrolona/análogos & derivados , Testosterona/uso terapêutico , Adulto , Análise de Variância , Índice de Massa Corporal , Método Duplo-Cego , Esquema de Medicação , Quimioterapia Combinada , Impedância Elétrica , Humanos , Masculino , Pessoa de Meia-Idade , Nandrolona/uso terapêutico , Decanoato de Nandrolona , Resultado do Tratamento
19.
Neth J Med ; 62(11): 454-5, 2004 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-15685897

RESUMO

This case report describes the diagnosis of Cushing's syndrome due to macronodular adrenal hyperplasia in an elderly woman who presented with fatigue, muscle weakness and oedema, and recent excessive bruising. Long-standing disease and comorbidity precluded adrenalectomy. Despite treatment with metyrapone and diuretics, the patient died after two months hospitalisation. Postmortal examination revealed overexpression of luteinising hormone (LH) receptors in the adrenal glands, suggesting that the postmenopausal rise in LH may have a role in adrenal hyperplasia and hypercortisolism.


Assuntos
Córtex Suprarrenal/patologia , Hiperfunção Adrenocortical/diagnóstico , Hiperfunção Adrenocortical/etiologia , Hiperfunção Adrenocortical/cirurgia , Idoso , Feminino , Humanos , Hiperplasia , Hipersecreção Hipofisária de ACTH/etiologia
20.
Qual Saf Health Care ; 12(3): 188-93, 2003 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-12792008

RESUMO

BACKGROUND: An HIV-specific version of the QUOTE questionnaire was developed to measure the quality of care of patients infected with HIV from the patients' perspective. The consistency and validity of the questionnaire was assessed. METHODS: Focus group discussions were held to select aspects for inclusion in the questionnaire that are important to patients with HIV. Item and inter-item analysis, factor analysis, and reliability analysis were performed to test the internal consistency and validity of the questionnaire. RESULTS: Twenty seven items (13 generic and 14 HIV specific) were used in the QUOTE-HIV questionnaire. Separate factor analyses of the generic and HIV specific aspects indicated that each loaded onto a single factor. The internal consistency of the total questionnaire was good (Cronbach's alpha >/=0.80). Feasibility of the questionnaire was shown by the diversity of importance and performance scores for general practitioners as well as for HIV specialists and AIDS nursing consultants. CONCLUSION: The QUOTE-HIV questionnaire is a useful instrument for measuring the quality of care from the perspective of HIV infected patients.


Assuntos
Infecções por HIV/terapia , Satisfação do Paciente/estatística & dados numéricos , Qualidade da Assistência à Saúde/estatística & dados numéricos , Inquéritos e Questionários/normas , Adulto , Estudos de Viabilidade , Feminino , Grupos Focais , Pesquisa sobre Serviços de Saúde , Humanos , Masculino , Pessoa de Meia-Idade , Países Baixos , Reprodutibilidade dos Testes
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