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1.
World J Clin Cases ; 12(3): 637-642, 2024 Jan 26.
Artigo em Inglês | MEDLINE | ID: mdl-38322476

RESUMO

BACKGROUND: Early initiation of enteral feeding is recognized to play a crucial role in improving the outcomes of treatment of acute pancreatitis. However, the method of administration of enteral nutrition remains debatable. We present the experience of treating a patient with moderate-severe acute pancreatitis, at high risk of progressing to a severe or fatal condition, using a novel method of selective feeding with duodenal isolation. CASE SUMMARY: A 27-year-old female patient presented to the emergency unit of the hospital with a typical manifestation of acute pancreatitis. Despite a conventional treatment, the patient's condition deteriorated by day 2 of hospitalization. Using an endoscopic approach, a novel catheter PandiCath® was placed to the duodenum of the patient, isolating its segment between the duodenal bulb and the ligament of Treitz. In the isolated area created, a negative pressure was applied, followed by introduction of early selective enteral feeding. The patient's condition subsequently improved in a rapid manner, and no complications often associated with moderate-to-severe acute pancreatitis developed. CONCLUSION: Within 48 h of starting treatment with the novel method, it can prevent the development of multiple organ failure and, when combined with minimally invasive drainage methods, help prevent infection.

2.
World J Gastrointest Endosc ; 14(10): 636-641, 2022 Oct 16.
Artigo em Inglês | MEDLINE | ID: mdl-36303813

RESUMO

BACKGROUND: Esophageal cancer is a common type of cancer and serious bleeding from esophageal tumors can occur in routine clinical practice. The arrest of bleeding from esophageal tumor is not a trivial task, which can sometimes require nonstandard solutions. We report a case of successful hemostasis of massive bleeding from esophageal tumor performed by a novel two-balloon catheter inserted endoscopically, with a local hemostatic treatment applied. CASE SUMMARY: A 36-years old male patient with advanced esophageal cancer developed bleeding from the tumor following endoscopic stenting with a self-expanding metal stent. Due to the ineffectiveness of standard approaches, after a medical conference, the patient was treated with a novel method based on the use of a two-balloon catheter creating an isolated area in esophagus and locally dispersing hemostatic polysaccharide powder inside the isolated interior. Hemostasis was successful and subsequent endoscopic examination revealed the presence of organized clot and localized defect, which was coagulated in a planned manner. CONCLUSION: The authors present a new catheter-based method of hemostasis of esophageal tumor bleeding.

3.
Biopreserv Biobank ; 19(1): 73-82, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33058731

RESUMO

The research biobanking field is developing rapidly in Russia. Over the course of the last decade, numerous biobanks were created or formed from existing collections of human and environmental biospecimens. The Russian National Association of Biobanks and Biobanking Specialists (NASBIO) was established in December 2018, aiming to: (1) unite professionals and research centers to create and develop a network of biobanks in Russia; (2) provide services and expertise in the field of biobanking; (3) execute various research projects utilizing biobanks' infrastructure; and (4) facilitate integration of Russian biomedical research centers into global research activities. The organizational structure, aims, and plans of this newly formed national association are reviewed in this article. The founders of NASBIO hope that the association will promote further development of biobanks and their networking in Russia, which is critically important for the success of national biomedical, pharmaceutical, and biotechnological research, and can facilitate international biobanking projects on a global scale.


Assuntos
Bancos de Espécimes Biológicos , Pesquisa Biomédica , Humanos , Federação Russa , Especialização
4.
Biopreserv Biobank ; 18(6): 533-546, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33164554

RESUMO

The era of COVID-19 has brought about a number of novel challenges for the global biobanking community. To better position the biobanking community to cope with current and future challenges, the International Society for Biological and Environmental Repositories (ISBER) COVID-19 Response Task Force was convened to identify needs and gaps in biobanking tools (existing resources that support good practice), for example, standards, best practices, business, etc. and to make recommendations to benefit the community. Toward these goals, the Task Force assembled a set of questions to explore individual biobanks' experiences, with emphasis on identification of key challenges and approaches, including tools employed. A survey was designed with the use of these questions and administered by ISBER. This article presents a summary of the aggregated data obtained from the survey responses, illustrating some of the major issues encountered and identifying which tools the survey respondents found most useful. In particular, this article focuses on the challenges identified during the early months of the COVID-19 era. Recommendations are provided to support biobank emergency preparedness for the future, address lessons learned, and propose solutions to bridge identified gaps. The analysis and the complete survey dataset will also inform the larger Task Force goal to develop specific tool recommendations.


Assuntos
Bancos de Espécimes Biológicos , COVID-19 , Pandemias , SARS-CoV-2/metabolismo , COVID-19/epidemiologia , COVID-19/metabolismo , Humanos
6.
Biopreserv Biobank ; 13(5): 371-5, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26417917

RESUMO

BACKGROUND: Poor nutrition during the early stages of human development can lead to rare pathological conditions in adult life. The best-known and most severe historical cases of famine include the Dutch 'Hunger Winter,' the Finnish famine, the Chinese Great famine, and the siege of Leningrad. The siege of Leningrad (now Saint Petersburg) was one of the longest in history, lasting 872 days, from September 8, 1941 to January 27, 1944. There were 670,000 registered deaths of the civil population, in which 97% died due to starvation. The aim of the present study is to create a collection of biospecimens from extensively phenotyped siege of Leningrad survivors, who underwent starvation during the early periods of their lives, and from a matched control group. METHODS: A total 305 siege survivors and 51 age- and sex- matched control subjects were investigated in of an observational retroprospective cohort study in 2009-2011 at a baseline visit. After 3 years of follow-up, 252 siege survivors (182 females and 70 males; mean age 74.7 ± 2.6 years) and 45 controls (32 females and 13 males; mean age 75.5 ± 2.8 years) were examined. All siege survivors were exposed to the extreme dietary restriction and stress associated with the siege in their early childhood. All participants signed informed consent and were subject to questionnaires and physical examination, as well as various laboratory and instrumental tests. Anthropometry, blood measurement, cognitive and physiological testing, and vascular damage assessment were performed. RESULTS: Blood specimens of the extensively phenotyped siege survivors were collected and processed (blood plasma, blood serum, and flash-frozen PBMC); serum and urine were used for laboratory tests. CONCLUSIONS: We believe that data obtained from this unique collection of biospecimens can elucidate the mechanisms of healthy aging and emphasize the importance of reproductive health, counseling, and monitoring among people with eating disorders.


Assuntos
Bancos de Espécimes Biológicos , Inanição , Sobreviventes/estatística & dados numéricos , Idoso , Feminino , Humanos , Masculino , Fenótipo , Estudos Retrospectivos , Federação Russa
7.
Cell Cycle ; 13(9): 1495-500, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24626177

RESUMO

It is proposed that patients with heart failure may have not only myocardial dysfunction, but also a reduced regenerative capacity of stem cells. However, very little is known about bone marrow stromal cell (BMSC) characteristics in heart failure and its comorbidities (obesity and/or diabetes). We hypothesized that metabolic alterations associated with the latter will be reflected in altered expression of key genes related to angiogenesis, inflammation, and tissue remodeling in patient-derived BMSCs. We found that BMSCs of heart failure patients with lower body mass index have enhanced expression of genes involved in extracellular matrix remodeling. In particular, body mass index<30 was associated with upregulated expression of genes encoding collagen type I, proteases and protease activators (MMP2, MMP14, uPA), and regulatory molecules (CTGF, ITGß5, SMAD7, SNAIL1). In contrast, these transcript levels did not differ significantly between BMSCs from obese heart failure patients and healthy subjects. Comorbidities (including obesity and diabetes) are known to play role in heart failure progression rate and outcome of the disease. We thus suggest that key molecular targets identified in this study should become the target of the subsequent focused studies. In the future, these targets may find some use in the clinical setting.


Assuntos
Insuficiência Cardíaca/metabolismo , Células-Tronco Mesenquimais/metabolismo , Adulto , Estudos de Casos e Controles , Feminino , Regulação da Expressão Gênica , Insuficiência Cardíaca/patologia , Humanos , Masculino , Pessoa de Meia-Idade , Cultura Primária de Células , Transcrição Gênica
8.
Biochimie ; 95(12): 2246-56, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-23871834

RESUMO

Mesenchymal stem cells have shown regenerative properties in many tissues. This feature had originally been ascribed to their multipotency and thus their ability to differentiate into tissue-specific cells. However, many researchers consider the secretome of mesenchymal stem cells the most important player in the observed reparative effects of these cells. In this review, we specifically focus on the potential neuroregenerative effect of mesenchymal stem cells, summarize several possible mechanisms of neuroregeneration and list key factors mediating this effect. We illustrate examples of mesenchymal stem cell treatment in central nervous system disorders including stroke, neurodegenerative disorders (such as Parkinson's disease, Huntington's disease, multiple system atrophy and cerebellar ataxia) and inflammatory disease (such as multiple sclerosis). We specifically highlight studies where mesenchymal stem cells have entered clinical trials.


Assuntos
Células-Tronco Mesenquimais/metabolismo , Regeneração Nervosa , Doenças Neurodegenerativas/terapia , Proteoma/metabolismo , Diferenciação Celular , Humanos , Esclerose Múltipla/terapia , Neurogênese/fisiologia , Comunicação Parácrina/fisiologia , Acidente Vascular Cerebral/terapia
9.
Int J Exp Pathol ; 94(3): 169-77, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23560418

RESUMO

This study aimed to investigate the effect of bone marrow- and adipose tissue-derived mesenchymal stem cell (BM-MSC and AD-MSC respectively) transplantation on left ventricular function and infarct area (IA) in the rat model of ischaemic heart failure. In anaesthetized Wistar rats, the left coronary artery (LCA) was occluded for 40 min with subsequent reperfusion for 7 days. Seven days following surgery, the animals with LCA occlusion/reperfusion were randomized into three groups: (i) Controls received intramyocardial injection of vehicle at three different locations within the peri-infarct zone, (ii) BM-MSC: cells were injected in the same way as in previous group (10(6) ), (iii) AD-MSC: using the same protocol as used in the BM-MSC group. In addition there was also a sham-treated group that had no injection. Two weeks following MSC transplantation, the hearts were isolated and perfused according to the Langendorff method followed by 30-min global ischaemia and 90-min reperfusion. After this IA was determined histologically. During Langendorff perfusion initial and postischaemic LV functions were the same in all groups although LV pressure at the 10th minute of reperfusion was higher in the AD-MSC group compared to controls. However, LV pressure during 30-min global ischaemia was significantly higher in BM-MSC as compared to controls and AD-MSC. The sham treated animals showed the same results as those seen with BM-MSC. Thus, BM-MSC transplantation, in contrast to transplantation of AD-MSC, resulted in better preservation of the LV ability to contract during ischaemia. Furthermore, IA was significantly smaller in BM-MSC group as compared to the controls and the AD-MSC groups. Thus this study has demonstrated that treatment with BM-MSC both ameliorates LV function and reduces histological scar size.


Assuntos
Tecido Adiposo/citologia , Transplante de Medula Óssea/métodos , Insuficiência Cardíaca/terapia , Transplante de Células-Tronco Mesenquimais/métodos , Isquemia Miocárdica/terapia , Remodelação Ventricular , Animais , Células Cultivadas , Doença Crônica , Modelos Animais de Doenças , Insuficiência Cardíaca/patologia , Masculino , Infarto do Miocárdio/patologia , Infarto do Miocárdio/terapia , Isquemia Miocárdica/patologia , Miocárdio/patologia , Ratos , Ratos Wistar , Função Ventricular Esquerda
10.
Mol Biol Int ; 2012: 793506, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22997578

RESUMO

Genomic imprinting is an epigenetic phenomenon that causes a differential expression of paternally and maternally inherited alleles of a subset of genes (the so-called imprinted genes). Imprinted genes are distributed throughout the genome and it is predicted that about 1% of the human genes may be imprinted. It is recognized that the allelic expression of imprinted genes varies between tissues and developmental stages. The current study represents the first attempt to estimate a prevalence of imprinted genes within the total human transcriptome. In silico analysis of the normalized expression profiles of a comprehensive panel of 173 established and candidate human imprinted genes was performed, in 492 publicly available SAGE libraries. The latter represent human cell and tissue samples in a variety of physiological and pathological conditions. Variations in the prevalence of imprinted genes within the total transcriptomes (ranging from 0.08% to 4.36%) and expression profiles of the individual imprinted genes are assessed. This paper thus provides a useful reference on the size of the imprinted transcriptome and expression of the individual imprinted genes.

11.
PLoS One ; 7(4): e35577, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22523602

RESUMO

Blood vessels and adjacent cells form perivascular stem cell niches in adult tissues. In this perivascular niche, a stem cell with mesenchymal characteristics was recently identified in some adult somatic tissues. These cells are pericytes that line the microvasculature, express mesenchymal markers and differentiate into mesodermal lineages but might even have the capacity to generate tissue-specific cell types. Here, we isolated, purified and characterized a previously unrecognized progenitor population from two different regions in the adult human brain, the ventricular wall and the neocortex. We show that these cells co-express markers for mesenchymal stem cells and pericytes in vivo and in vitro, but do not express glial, neuronal progenitor, hematopoietic, endothelial or microglial markers in their native state. Furthermore, we demonstrate at a clonal level that these progenitors have true multilineage potential towards both, the mesodermal and neuroectodermal phenotype. They can be epigenetically induced in vitro into adipocytes, chondroblasts and osteoblasts but also into glial cells and immature neurons. This progenitor population exhibits long-term proliferation, karyotype stability and retention of phenotype and multipotency following extensive propagation. Thus, we provide evidence that the vascular niche in the adult human brain harbors a novel progenitor with multilineage capacity that appears to represent mesenchymal stem cells and is different from any previously described human neural stem cell. Future studies will elucidate whether these cells may play a role for disease or may represent a reservoir that can be exploited in efforts to repair the diseased human brain.


Assuntos
Células-Tronco Adultas/citologia , Células-Tronco Mesenquimais/citologia , Células-Tronco Multipotentes/citologia , Actinas/biossíntese , Adulto , Diferenciação Celular , Linhagem da Célula , Ventrículos Cerebrais/citologia , Células Clonais , Humanos , Neocórtex/citologia , Pericitos/citologia , Receptor beta de Fator de Crescimento Derivado de Plaquetas/biossíntese
12.
Cell Cycle ; 11(2): 377-83, 2012 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-22189711

RESUMO

Bone marrow (BM) and subcutaneous adipose tissue (Ad) are both considered being prospective sources of MSC for therapeutic applications. However, functional properties and therapeutic efficacy of MSC derived from different tissues of the same patient are still poorly investigated. In our study, BM-MSC and F-MSC cultures from 43 adult donors were evaluated in successive passages for immunophenotype, secretion of VEGF, SDF1, MCP1, IL6 and TGFß1, frequency of colony-forming units (CFU-F), frequency of adipo- and osteo-progenitors (CFU-Ad, CFU-Ost), and for onset of in vitro replicative senescence. We have demonstrated that at early passages (P2-P4 or up to 14-15 in vitro population doublings) BM- and Ad- derived MSC cultures are comparable in such important characteristics as proliferation rate (population doubling time: 3.4±0.2% in BM-MSC, 3±0.3% in F-MSC), clonogenity (CFU-F frequency: 32±5% in BM-MSC, 31±5% in F-MSC), differentiation potential (CFU-Ad frequency: 10.4±2% in BM-MSC, 13±3% in F-MSC; CFU-Ost frequency: 18.5±5.5% in BM-MSC, 18±5% in F-MSC), but differ significantly in abundance of CD146⁺ fraction within the sample (25±5% in BM-MSC, 7±3% in F-MSC) and in a level of VEGF, SDF-1, MCP1 and TGFß1 secretion. We have also demonstrated that BM-MSC enter senescence after P3-4 while most of F-MSC did not show senescence features up to P6-8. Together, these data demonstrate that specific properties of MSC from different sources should be always taken into account, when developing and optimizing the specific protocols for MSC expansion and evaluation for each particular clinical application.


Assuntos
Células da Medula Óssea/fisiologia , Células-Tronco Mesenquimais/fisiologia , Gordura Subcutânea/citologia , Antígenos de Diferenciação/metabolismo , Células da Medula Óssea/metabolismo , Diferenciação Celular , Linhagem da Célula , Proliferação de Células , Células Cultivadas , Senescência Celular , Ensaio de Unidades Formadoras de Colônias , Citocinas/metabolismo , Humanos , Imunofenotipagem , Células-Tronco Mesenquimais/metabolismo
13.
Cell Mol Biol Lett ; 16(1): 79-88, 2011 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-21161417

RESUMO

The majority of human embryonic stem cell lines depend on a feeder cell layer for continuous growth in vitro, so that they can remain in an undifferentiated state. Limited knowledge is available concerning the molecular mechanisms that underlie the capacity of feeder cells to support both the proliferation and pluripotency of these cells. Importantly, feeder cells generally lose their capacity to support human embryonic stem cell proliferation in vitro following long-term culture. In this study, we performed large-scale gene expression profiles of human foreskin fibroblasts during early, intermediate and late passages using a custom DNA microarray platform (NeuroStem 2.0 Chip). The microarray data was validated using RT-PCR and virtual SAGE analysis. Our comparative gene expression study identified a limited number of molecular targets potentially involved in the ability of human neonatal foreskin fibroblasts to serve as feeder cells for human embryonic stem cell cultures. Among these, the C-KIT, leptin and pigment epithelium-derived factor (PEDF) genes were the most interesting candidates.


Assuntos
Células-Tronco Embrionárias/citologia , Fibroblastos/metabolismo , Proteínas do Olho/genética , Proteínas do Olho/metabolismo , Prepúcio do Pênis/citologia , Perfilação da Expressão Gênica , Humanos , Masculino , Fatores de Crescimento Neural/genética , Fatores de Crescimento Neural/metabolismo , Análise de Sequência com Séries de Oligonucleotídeos , Proteínas Proto-Oncogênicas c-kit/genética , Proteínas Proto-Oncogênicas c-kit/metabolismo , Serpinas/genética , Serpinas/metabolismo
14.
Stem Cell Rev Rep ; 6(3): 411-24, 2010 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-20300888

RESUMO

Unique biological properties of stem cells make them a precious source of cell material for treatment of a number of pathological conditions. Among issues inhibiting transition of stem cell technologies to the clinics, the risk of oncological complications of stem cell-based therapies is the most critical. A massive amount of clinical and experimental data demonstrates that both hematological (including acute and chronic myeloid leukemia) and non-hematological (including teratoma and non-teratoma tumors) malignancies could arise from donor stem cells of different types. A wide spectrum of mechanisms could underlie the development of oncological disease in recipients, including: i) blast transformation of proliferating donor stem cells under persistent action of certain factors in the recipient, thus causing de novo malignancies; ii) contamination of donor cell material with malignant cells; iii) transmission of particular viral subtypes with donor stem cells, combined with immunosuppression therapy effects; iv) uncontrollable proliferation of residual undifferentiated stem cells of various plasticity; and v) karyotypic instability in stem cells following prolonged culturing/expansion in vitro. Potential preventive strategies are diverse and include i) high-throughput cell sorting-based strategies; ii) introduction of suicide genes into the donor stem cell genome; iii) application of apoptosis-inducing epigenetic factors; and some other options.


Assuntos
Neoplasias/etiologia , Transplante de Células-Tronco/efeitos adversos , Animais , Humanos , Terapia de Imunossupressão/efeitos adversos , Terapia de Imunossupressão/métodos , Modelos Biológicos , Medição de Risco , Transplante de Células-Tronco/métodos , Condicionamento Pré-Transplante/efeitos adversos , Condicionamento Pré-Transplante/métodos
15.
Rev Neurosci ; 20(5-6): 347-81, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-20397620

RESUMO

Motor dysfunctions in Parkinson's disease are believed to be primarily due to the degeneration of dopaminergic neurons located in the substantia nigra pars compacta. Because a single-type cell population is depleted, Parkinson's disease is considered a primary target for cell replacement-based therapeutic strategies. Extensive studies have confirmed transplantation of donor neurons could be beneficial, yet identifying an alternative cell source is clearly essential. Human embryonic stem cells (hESCs) have been proposed as a renewable source of dopaminergic neurons for transplantation in Parkinson's disease; other potential sources could include neural stem cells (hNSCs) and adult mesenchymal stem cells (hMSCs). However, numerous difficulties avert practical application of stem cell-based therapeutic approaches for the treatment of Parkinson's disease. Among the latter, ethical, safety (including xeno- and tumor formation-associated risks) and technical issues stand out. This review aims to provide a balanced and updated outlook on various issues associated with stem cells in regard to their potential in the treatment of Parkinson's disease. Essential features of the individual stem cell subtypes, principles of available differentiation protocols, transplantation, and safety issues are discussed extensively.


Assuntos
Transplante de Células/métodos , Doença de Parkinson/cirurgia , Células-Tronco/fisiologia , Animais , Humanos
16.
Front Neurosci ; 2(1): 26-34, 2008 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-18982104

RESUMO

Human embryonic stem cells (hESCs) are a potential source of dopaminergic neurons for treatment of patients with Parkinson's disease (PD). Dopaminergic neurons can be derived from hESCs and display a characteristic midbrain phenotype. Once transplanted, they can induce partial behavioral recovery in animal models of PD. However, the potential research field faces several challenges that need to be overcome before clinical application of hESCs in a transplantation therapy in PD can be considered. These include low survival of the hESC-derived, grafted dopaminergic neurons after transplantation; unclear functional integration of the grafted neurons in the host brain; and, the risk of teratoma/tumor formation from the transplanted cells. This review is focused on our recent efforts to improve the survival of hESC-dervied dopaminergic neurons. In a recent study, we examined the effect of fibroblast growth factor (FGF)-20 in the differentiation of hESCs into dopaminergic neurons. We supplemented cultures of hESCs with FGF-20 during differentiation on PA6 mouse stromal cells for 3 weeks. When we added FGF-20 the yield of neurons expressing tyrosine hydroxylase increased. We demonstrated that at least part of the effect is contributed by enhanced cell differentiation towards the dopaminergic phenotype as well as reduced cell death. We compare our results with those obtained in other published protocols using different sets of growth factors. Taken together, our data indicate that FGF-20 has potent effects to generate large number of dopaminergic neurons derived from hESCs, which may be useful for hESC-based therapy in PD.

18.
Curr Pharm Biotechnol ; 9(5): 338-50, 2008 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-18855686

RESUMO

A number of molecular methods of gene expression analysis can approach genomic level. Among those, Serial Analysis of Gene Expression (SAGE) stands out. Unlike many other techniques, SAGE allows both qualitative and quantitative analysis of previously unknown transcripts. Over the course of the last 13 years, SAGE has became a recognized tool of large-scale gene expression profiling, being used extensively in human, animal, yeast and plant studies of various nature. A number of important adaptations was introduced both to the protocol of SAGE library construction and to the analytical algorithm employed. Moreover, some variations of the original protocol (MAGE, SADE, microSAGE, miniSAGE, longSAGE, superSAGE, deepSAGE, etc.) were derived to improve the utility of SAGE in certain conditions. Current review aims comparing the benefits and drawbacks of the techniques for high-throughput gene expression analysis (including SAGE) in a realistic, balanced manner. Issues related to modifications to the original protocol and further development of the SAGE are discussed.


Assuntos
Mapeamento Cromossômico/métodos , Biologia Computacional/métodos , Etiquetas de Sequências Expressas , Perfilação da Expressão Gênica/tendências , Proteoma/metabolismo , Pesquisa/tendências , Fatores de Transcrição/metabolismo , Previsões
19.
Cells Tissues Organs ; 188(1-2): 31-45, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-18303244

RESUMO

Knowledge of the transcriptional circuitry responsible for pluripotentiality and self-renewal in embryonic stem cells is tantamount to understanding early mammalian development and a prerequisite to determining their therapeutic potential. Various techniques have employed genomics to identify transcripts that were abundant in stem cells, in an attempt to define the molecular basis of 'stemness'. In this study, we have extended traditional genomic analyses to identify cis-elements that might be implicated in the control of embryonic stem cell-restricted gene promoters. The strategy relied on the generation of a problem-specific list from serial analysis of gene expression profiles and subsequent promoter analyses to identify frameworks of multiple cis-elements conserved in space and orientation among genes from the problem-specific list. Subsequent experimental data suggest that 2 novel transcription factors, B-Myb and Maz, predicted from these models, are implicated either in the maintenance of the undifferentiated stem cell state or in early steps of differentiation.


Assuntos
Redes Reguladoras de Genes , Células-Tronco Pluripotentes/metabolismo , Animais , Sequência de Bases , Linhagem Celular , Imunoprecipitação da Cromatina , Sequência Conservada , Perfilação da Expressão Gênica , Regulação da Expressão Gênica no Desenvolvimento , Camundongos , Modelos Genéticos , Dados de Sequência Molecular , Células-Tronco Pluripotentes/citologia , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Sequências Reguladoras de Ácido Nucleico/genética , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Fatores de Transcrição/metabolismo
20.
Methods Mol Biol ; 371: 249-65, 2007.
Artigo em Inglês | MEDLINE | ID: mdl-17634587

RESUMO

The emergence of microarray technology as a novel tool in molecular biology has led to significant progress in many biomedical disciplines, including gerontology. Both cDNA and oligonucleotide-based DNA microarrays are now widely used to identify the basic physiological mechanisms of aging and to uncover the molecular mechanisms underlying the biological effects of anti-aging drugs. Two different protocols covering both cDNA and oligonucleotide microarray platforms, with radioactive and nonradioactive (fluorescent) labeling, are detailed in the manuscript. These in-depth protocols provide a background for the technical aspects of everyday work with DNA microarrays.


Assuntos
Envelhecimento , Análise de Sequência com Séries de Oligonucleotídeos/métodos , Animais , Humanos
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