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1.
G Ital Nefrol ; 36(5)2019 Sep 24.
Artigo em Italiano | MEDLINE | ID: mdl-31580547

RESUMO

Administrative databases contain precious information that can support the identification of specific pathologies. Specifically, chronic kidney disease (CKD) patients could be identified using hospital discharge records (HDR); these should contain information on the CKD stage using subcategories of the ICD9-CM classification's 585 code (subcategories can be expressed just by adding a fourth digit to this code). To verify the accuracy of HDR data regarding the coding of CKD collected in the Italian region Emilia-Romagna, we analyzed the HDR records of patients enrolled in the PIRP project, which could easily be matched with eGFR data obtained through laboratory examinations. The PIRP database was used as the gold standard because it contains data on CKD patients followed up since 2004 in thirteen regional nephrology units and includes data obtained from reliable and homogeneous laboratory measurement. All HDR of PIRP patients enrolled between 2009 and 2017 were retrieved and matched with available laboratory data on eGFR, collected within 15 days before or after discharge. We analyzed 4.168 HDR, which were classified as: a) unreported CKD (n=1.848, 44.3%); b) unspecified CKD, when code 585.9 (CKD, not specified) or 586 was used (n=446, 10.7%); c) wrong CKD (n=833, 20.0%); d) correct CKD (n=1041, 25.0%). We noticed the proportion of unreported CKD growing from 32.9% in 2009 to 56.6% in 2017, and the correspondent proportion of correct CKDs decreasing from 25.4% to 22.3%. Across disciplines, Nephrology showed the highest concordance (69.1%) between the CKD stage specified in the HDRs and the stage reported in the matched laboratory exam, while none of the other disciplines, except for Geriatrics, reached 20% concordance. When the CKD stage was incorrectly coded, it was generally underestimated; among HDRs with unreported or unspecified CKD at least half of the discharges were matched with lab exams reporting CKD in stage 4 or 5. We found that the quality of CKD stage coding in the HDR record database was very poor, and insufficient to identify CKD patients unknown to nephrologists. Moreover, the growing proportion of unreported CKD could have an adverse effect on patients' timely referral to a nephrologist, since general practitioners might remain unaware of their patients' illness. Actions aimed at improving the training of the operators in charge of HDRs compilation and, most of all, at allowing the exploitation of the informative potential of HDRs for epidemiological research are thus needed.


Assuntos
Codificação Clínica/normas , Confiabilidade dos Dados , Alta do Paciente/normas , Insuficiência Renal Crônica/diagnóstico , Idoso , Feminino , Taxa de Filtração Glomerular , Humanos , Itália , Masculino , Nefrologia , Encaminhamento e Consulta , Insuficiência Renal Crônica/patologia , Sensibilidade e Especificidade
2.
J Surg Res ; 179(1): e21-9, 2013 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-22475350

RESUMO

BACKGROUND: Permanence of grafted stem cells in the infarcted myocardial area has been suggested to be favored by tissue engineering strategies, including the application of a scaffold as a cell support. However, an estimation of how many cells remain localized in the site of transplantation has never been done. The aim of this work was to investigate the localization of mesenchymal stem cells (MSCs) grafted with a well cell-adhesive polymer in the scar region of the infarcted heart. MATERIALS AND METHODS: Rat MSCs were engineered in a hyaluronan-based scaffold (HYAFF(®)11) for 3 wk. The hearts of donor rats were also explanted, subjected to coronary artery ligation, and grafted into the abdomen of syngeneic rats. Two wk after coronary ligation a small dish of the HYAFF(®)11/MSC construct was introduced into a pouch created in the ventricular wall of the infarct area and left for 2 wk. RESULTS: Under ex vivo conditions, MSCs tightly adhered to the hyaluronan fibers and secreted abundant extracellular matrix. In contrast, HYAFF(®)11 was not more surrounded by the engrafted MSCs 2 wk after construct transplantation. Most MSCs migrated near the border zone of the infarcted area close to the coronary vessels. Moreover, the infarcted region of the heart was enriched in capillaries and the degree of fibrosis was attenuated. CONCLUSIONS: Two wk after transplantation most MSCs grafted in the infarcted myocardium with HYAFF(®)11 had left the scaffold and moved to the border zone. Nevertheless, this treatment increased the myocardial vascularization and reduced the degree of fibrosis in the scar area.


Assuntos
Ácido Hialurônico , Transplante de Células-Tronco Mesenquimais/métodos , Infarto do Miocárdio/patologia , Infarto do Miocárdio/cirurgia , Engenharia Tecidual/métodos , Alicerces Teciduais , Animais , Adesão Celular/fisiologia , Movimento Celular/fisiologia , Células Cultivadas , Cicatriz/patologia , Vasos Coronários/fisiologia , Modelos Animais de Doenças , Fibrose Endomiocárdica/prevenção & controle , Masculino , Células-Tronco Mesenquimais/patologia , Ratos , Ratos Endogâmicos Lew , Resultado do Tratamento
3.
Cell Struct Funct ; 36(1): 49-56, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21317539

RESUMO

The precise location of rDNA transcription to the components of mammalian cell nucleolus is still debated. This was due to the fact that all the molecules necessary for rRNA synthesis are located in two of the three components, the fibrillar centers (FCs) and the dense fibrillar component (DFC), which together with the granular component (GC) are considered to be constantly present in mammalian cell nucleoli. In the present study we demonstrated that in nucleoli of many regenerating rat hepatocytes at 15 h after partial hepatectomy the FCs were no longer present, only the DFC and the GC being detected. At this time of regeneration the rRNA transcriptional activity was three fold that of resting hepatocytes, while the synthesis of DNA was not yet significantly increased, indicating that these nucleolar changes were due to the rRNA synthesis up-regulation. The DFC appeared to be organized in numerous, small, roundish tufts of fibrils. The silver staining procedure for AgNOR proteins, which are associated with the ribosomal genes, selectively and homogeneously stained these fibrillar tufts. Immuno-gold visualization of the Upstream Binding Factor (UBF), which is associated with the promoter region and the transcribed portion of the rRNA 45S gene, demonstrated that UBF was selectively located in the fibrillar tufts. We concluded that in proliferating rat hepatocytes the increased synthesis of rRNA induced an activation of the rRNA transcription machinery located in the fibrillar centers which, by becoming associated with the ribonucleoprotein transcripts, assumed the morphological pattern of the DFC.


Assuntos
Nucléolo Celular/ultraestrutura , Hepatócitos/citologia , RNA Ribossômico/genética , Transcrição Gênica , Animais , DNA Ribossômico/genética , Hepatectomia , Hepatócitos/metabolismo , Hepatócitos/ultraestrutura , Regeneração Hepática , Ratos , Ratos Wistar , Coloração pela Prata
4.
Cytotherapy ; 12(3): 275-87, 2010 May.
Artigo em Inglês | MEDLINE | ID: mdl-20230218

RESUMO

BACKGROUND AIMS: The presence of ectopic tissues in the pathologic artery wall raises the issue of whether multipotent stem cells may reside in the vasculature itself. Recently mesenchymal stromal cells (MSC) have been isolated from different human vascular segments (VW MSC), belying the previous view that the vessel wall is a relatively quiescent tissue. METHODS: Resident multipotent cells were recovered from fresh arterial segments (aortic arches, thoracic and femoral arteries) collected in a tissue-banking facility and used to establish an in situ and in vitro study of the stemness features and multipotency of these multidistrict MSC populations. RESULTS: Notch-1+, Stro-1+, Sca-1+ and Oct-4+ cells were distributed along an arterial wall vasculogenic niche. Multidistrict VW MSC homogeneously expressed markers of stemness (Stro-1, Notch-1 and Oct-4) and MSC lineages (CD44, CD90, CD105, CD73, CD29 and CD166) whilst they were negative for hematopoietic and endothelial markers (CD34, CD45, CD31 and vWF). Each VW MSC population had characteristics of stem cells, i.e. a high efflux capability for Hoechst 33342 dye and the ability to form spheroids when grown in suspension and generate colonies when seeded at low density. Again, VW MSC cultured in induction media exhibited adipogenic, chondrogenic and leiomyogenic potential but less propensity to osteogenic differentiation, as documented by histochemical, immunohistochemical, molecular and electron microscopy analysis. CONCLUSIONS: Overall, these findings may enlighten the physiopathologic mechanisms of vascular wall diseases as well as having potential implications for cellular, genetic and tissue engineering approaches to treating vascular pathologies when these are unresponsive to medical and surgical therapies.


Assuntos
Artérias/citologia , Células-Tronco Mesenquimais , Células-Tronco Pluripotentes , Biomarcadores/metabolismo , Diferenciação Celular/fisiologia , Linhagem da Célula , Separação Celular , Células Cultivadas , Citometria de Fluxo , Humanos , Imunofenotipagem , Células-Tronco Mesenquimais/citologia , Células-Tronco Mesenquimais/fisiologia , Células-Tronco Pluripotentes/citologia , Células-Tronco Pluripotentes/fisiologia
5.
Microbiology (Reading) ; 156(Pt 6): 1609-1618, 2010 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-20167618

RESUMO

Bifidobacterium animalis subsp. lactis lives in the gastrointestinal tract of most mammals, including humans. Recently, for the probiotic strain B. animalis subsp. lactis BI07, a dose-dependent plasminogen-binding activity was demonstrated and five putative plasminogen-binding proteins were identified. Here we investigated the role of surface DnaK as a B. animalis subsp. lactis BI07 plasminogen receptor. DnaK was visualized on the bacterial cell surface by transmission electron microscopy. The His-tagged recombinant DnaK protein showed a high affinity for human plasminogen, with an equilibrium dissociation constant in the nanomolar range. The capability to tolerate physiological concentrations of bile salts is a crucial feature for an intestinal symbiont micro-organism. By proteome analysis we demonstrated that the long-term exposure of B. animalis subsp. lactis BI07 to bile salts results in the upregulation of important surface plasminogen receptors such as DnaK and enolase. Moreover, adaptation of B. animalis subsp. lactis BI07 to physiological concentrations of bile salts significantly increased its capacity to interact with the host plasminogen system. By enhancing the bacterial capacity to interact with the host plasminogen, the gut bile environment may facilitate the colonization of the human host by B. animalis subsp. lactis BI07.


Assuntos
Proteínas de Bactérias/metabolismo , Bifidobacterium/metabolismo , Ácidos e Sais Biliares/metabolismo , Trato Gastrointestinal/microbiologia , Proteínas de Choque Térmico HSP70/metabolismo , Plasminogênio/metabolismo , Regulação para Cima , Proteínas de Bactérias/análise , Bifidobacterium/química , Bifidobacterium/crescimento & desenvolvimento , Proteínas de Choque Térmico HSP70/análise , Humanos , Microscopia Eletrônica de Transmissão , Fosfopiruvato Hidratase/metabolismo , Proteoma/análise , Proteínas Recombinantes/metabolismo
6.
Tissue Eng Part A ; 15(9): 2751-62, 2009 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-19438299

RESUMO

Neovascularization can be improved using polymer scaffolds supporting endothelial progenitor cells (EPCs). The aim of the present study was to investigate whether human early EPCs (eEPCs) could be efficiently cultured in a hyaluronan-based non-woven mesh (HYAFF-11). eEPCs were seeded on HYAFF-11 at the density of 1 x 10(6)/cm(2) and cultured with endothelial differentiating factors for 3 weeks. After 24 h, nearly 90% of EPCs were adherent. Cell viability, evaluated by methyltetrazolium test, was greater in HYAFF-11 than on the most commonly used fibronectin-coated dishes, even if a progressive decline in viability was observed starting from approximately the second week of culture. eEPCs easily migrated to and aggregated on the scaffold. Evidence of active protein synthesis and features of endothelial differentiation, including cellular transcytotic channels and micropinocytotic vesicles, was revealed using electron microscopy, immunofluorescence, and reverse transcriptase polymerase chain reaction analysis. eEPCs cultured in the scaffold also showed a certain angiogenic activity, as demonstrated by hepatocyte growth factor transcription and vascular endothelial growth factor secretion. In conclusion, eEPCs can migrate and adhere inside HYAFF-11, maintain their pre-endothelial phenotype, and express angiogenic factors, especially within the first week of growth. These results indicate that non-woven HYAFF-11 could be a promising candidate as a vehicle for eEPCs for regenerative medicine applications.


Assuntos
Células Endoteliais/citologia , Células Endoteliais/efeitos dos fármacos , Ácido Hialurônico/farmacologia , Polímeros/farmacologia , Células-Tronco/citologia , Células-Tronco/efeitos dos fármacos , Alicerces Teciduais/química , Biomarcadores/metabolismo , Adesão Celular/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Células Cultivadas , Células Endoteliais/ultraestrutura , Imunofluorescência , Humanos , Microscopia Eletrônica de Varredura , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Células-Tronco/ultraestrutura , Fator A de Crescimento do Endotélio Vascular/metabolismo
7.
Ultrastruct Pathol ; 31(6): 401-7, 2007.
Artigo em Inglês | MEDLINE | ID: mdl-18098058

RESUMO

Cooperation between research communities and software-development teams has led to the creation of novel software. The purpose of this paper is to show an alternative work method based on the usage of ImageJ (http://rsb.info.nih.gov/ij/), which can be effectively employed in solving common microscopic and ultrastructural image analysis tasks. As an open-source software, ImageJ provides the possibility to work in a free-development/sharing world. Its very "friendly" graphical user interface helps users to manage and edit biomedical images. The on-line material such as handbooks, wikis, and plugins leads users through various functions, giving clues about potential new applications. ImageJ is not only a morphometric analysis software, it is sufficiently flexible to be adapted to the numerous requirements tasked in the laboratories as routine as well as research demands. Examples include area measurements on selectively stained tissue components, cell count and area measurements at single cell level, immunohistochemical antigen quantification, and immunoelectron microscopy gold particle count.


Assuntos
Processamento de Imagem Assistida por Computador , Microscopia Eletrônica de Transmissão/instrumentação , Microscopia Eletrônica de Transmissão/métodos , Animais , Comportamento Cooperativo , Feminino , Humanos , Imuno-Histoquímica , Ratos , Software
8.
Stem Cells ; 25(7): 1627-34, 2007 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-17446560

RESUMO

The clinical use of endothelial progenitor cells is hampered by difficulties in obtaining an adequate number of functional progenitors. This study aimed to establish whether human thoracic aortas harvested from healthy multiorgan donors can be a valuable source of angiogenic progenitors. Immunohistochemical tissue studies showed that two distinct cell populations with putative stem cell capabilities, one composed of CD34+ cells and the other of c-kit+ cells, are present in between the media and adventitia of human thoracic aortas. Ki-67+ cells with high growth potential were located in an area corresponding to the site of CD34+ and c-kit+ cell residence. We thus isolated cells (0.5 approximately 2.0 x 10(4) aortic progenitors per 25 cm2) which, upon culturing, coexpressed molecules of mesenchymal stromal cells (i.e., CD44+, CD90+, CD105+) and showed a transcript expression of stem cell markers (e.g., OCT4, c-kit, BCRP-1, Interleukin-6) and BMI-1. Cell expansion was adequate for use in a clinical setting. A subset of cultured cells acquired the phenotype of endothelial cells in the presence of vascular endothelial growth factor (e.g., increased expression of KDR and von Willebrand factor positivity), as documented by flow cytometry, immunofluorescence, electron microscopy, and reverse transcription-polymerase chain reaction assays. An in vitro angiogenesis test kit revealed that cells were able to form capillary-like structures within 6 hours of seeding. This study demonstrates that thoracic aortas from multiorgan donors yield mesenchymal stromal cells with the ability to differentiate in vitro into endothelial cells. These cells can be used for the creation of an allogenic bank of angiogenic progenitors, thus providing new options for restoring vascularization at ischemic sites. Disclosure of potential conflicts of interest is found at the end of this article.


Assuntos
Aorta Torácica/citologia , Vasos Sanguíneos/citologia , Separação Celular/métodos , Células-Tronco Mesenquimais/citologia , Células Estromais/citologia , Doadores de Tecidos , Adulto , Antígenos CD34/metabolismo , Diferenciação Celular , Células Cultivadas , Feminino , Citometria de Fluxo , Imunofluorescência , Humanos , Masculino , Proteínas Proto-Oncogênicas c-kit/metabolismo , Fator A de Crescimento do Endotélio Vascular/metabolismo
9.
Ultrastruct Pathol ; 31(1): 23-31, 2007.
Artigo em Inglês | MEDLINE | ID: mdl-17455095

RESUMO

Human mesenchymal stromal (stem) cells (hMSCs) isolated from adult bone marrow (BM-hMSCs) as well as amnion (AM-hMSCs) and chorion (CM-hMSCs) term placenta leaves were studied by transmission electron microscopy (TEM) to investigate their ultrastructural basic phenotype. At flow cytometry, the isolated cells showed a homogeneous expression of markers commonly used to identify hMSCs, i.e., CD105, CD44, CD90, CD166, HLA-ABC positivities, and CD45, AC133, and HLA-DR negativities. However, TEM revealed subtle yet significant differences. BM-hMSCs had mesenchymal features with dilated cisternae of rough endoplasmic reticulum (rER) and peripheral collections of multiloculated clear blisters; this latter finding mostly representing complex foldings of the plasma membrane could be revelatory of the in situ cell arrangement in the niche microenvironment. Unlike BM-hMSCs, CM-hMSCs were more primitive and metabolically quiescent, their major features being the presence of rER stacks and large peripheral collections of unbound glycogen. AM-hMSCs showed a hybrid epithelial-mesenchymal ultrastructural phenotype; epithelial characters included non-intestinal-type surface microvilli, intracytoplasmic lumina lined with microvilli, and intercellular junctions; mesenchymal features included rER profiles, lipid droplets, and well-developed foci of contractile filaments with dense bodies. These features are consistent with the view that AM-hMSCs have a pluripotent potential. In conclusion, this study documents that ultrastructural differences exist among phenotypically similar hMSCs derived from human bone marrow and term placenta leaves; such differences could be revelatory of the hMSCs in vitro differentiation potential and may provide useful clues to attempt their in situ identification.


Assuntos
Células-Tronco Adultas/ultraestrutura , Células da Medula Óssea/ultraestrutura , Células-Tronco Mesenquimais/ultraestrutura , Placenta/ultraestrutura , Células-Tronco Pluripotentes/ultraestrutura , Adulto , Células-Tronco Adultas/imunologia , Âmnio/ultraestrutura , Antígenos CD/análise , Células da Medula Óssea/imunologia , Separação Celular , Células Cultivadas , Córion/ultraestrutura , Feminino , Citometria de Fluxo , Antígenos HLA-A/análise , Humanos , Imunofenotipagem , Células-Tronco Mesenquimais/imunologia , Microscopia Eletrônica de Transmissão , Fenótipo , Placenta/citologia , Placenta/imunologia , Células-Tronco Pluripotentes/imunologia , Células Estromais/ultraestrutura
10.
Cell Tissue Bank ; 7(2): 123-33, 2006.
Artigo em Inglês | MEDLINE | ID: mdl-16732415

RESUMO

New and often aggressive treatment schemes allow the successful healing of many young patients with cancer, but the price the young women have to pay is high: many of them lose ovarian function and fertility. Due to the improved long-term survival of adolescents and young women with malignancies undergoing gonadotoxic chemotherapy, preservation of future fertility has been the focus of recent ubiquitarian interest. A feasible solution is the cryopreservation of ovarian tissue. Ovarian tissue, after thawing, can be used in three different ways: 1. grafted into its normal site (orthotopic); 2. grafted into a site other than its normal position (heterotopic), necessitating recourse to in vitro fertilization (IVF); 3. grown and in vitro matured in order to obtain metaphase II oocytes for an IVF program. It is believed that protein supplementation, in cryopreservation solution, is essential for improving ovarian tissue cryopreservation. The aim of this study was to evaluate the ultrastructural appearance of human ovarian tissue cryopreserved in 1.5 M 1,2 propanediol (PROH), 0.2 M sucrose using different protein sources: fetal calf serum (FCS), plasmanate or syntetic serum substitute (SSS). Fresh and frozen/thawed ovarian tissues were compared by transmission electron microscope (TEM), to evaluate the appearance of stromal and follicle cells as affected by different protein sources. Our data indicate that FCS is a better protein support for ovarian tissue cryopreservation when compared to SSS or Plasmanate. In addition the follicles are more resistant to the cryopreservation with respect to stroma.


Assuntos
Criopreservação/métodos , Folículo Ovariano/ultraestrutura , Ovário/citologia , Células Estromais/ultraestrutura , Adolescente , Adulto , Animais , Proteínas Sanguíneas/metabolismo , Bovinos , Técnicas de Cultura de Células , Células Cultivadas , Crioprotetores/farmacologia , Feminino , Fertilidade , Humanos , Folículo Ovariano/citologia , Folículo Ovariano/efeitos dos fármacos , Neoplasias Ovarianas/tratamento farmacológico , Ovário/efeitos dos fármacos , Ovário/ultraestrutura , Substitutos do Plasma/metabolismo , Propilenoglicol/farmacologia , Albumina Sérica , Soroalbumina Bovina/metabolismo , Albumina Sérica Humana , Soroglobulinas , Células Estromais/citologia , Células Estromais/efeitos dos fármacos , Sacarose/farmacologia
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