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1.
Nutr Metab Cardiovasc Dis ; 27(9): 768-774, 2017 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-28739184

RESUMO

BACKGROUND AND AIMS: Recent studies highlighted the role of calcification processes in the clinical progression of chronic cardiovascular diseases. In this study we investigated the relationship between the chemical composition of calcification and atherosclerotic plaque stability in carotid arteries. METHODS AND RESULTS: To this end, we characterized the calcification on 229 carotid plaques, by morphology, immunohistochemistry, transmission electron microscopy and energy dispersive X-ray microanalysis. Plaques were classified into two categories: unstable and stable. No significant differences were found in the incidence of the various risk factors between patients with and without carotid calcification, with the exception of diabetes. The energy dispersive X-ray microanalysis allowed us to identify two types of calcium salts in the atheromatous plaques, hydroxyapatite (HA) and calcium oxalate (CO). Our results showed that calcification is a common finding in carotid plaques, being present in 77.3% of cases, and the amount of calcium is not a factor of vulnerability. Noteworthy, we observed an association between HA calcification and unstable plaques. On the contrary, CO calcifications were mainly detected in stable plaques. CONCLUSIONS: The presence of different types of calcification in atheromatous plaques may open new perspectives in understanding the molecular mechanisms of atheroma formation and plaque instability.


Assuntos
Oxalato de Cálcio/análise , Artérias Carótidas/química , Doenças das Artérias Carótidas/metabolismo , Durapatita/análise , Placa Aterosclerótica , Calcificação Vascular/metabolismo , Idoso , Biomarcadores/análise , Biópsia , Artérias Carótidas/ultraestrutura , Doenças das Artérias Carótidas/patologia , Progressão da Doença , Feminino , Humanos , Imuno-Histoquímica , Masculino , Microscopia Eletrônica de Transmissão , Pessoa de Meia-Idade , Fatores de Risco , Ruptura Espontânea , Espectrometria por Raios X , Calcificação Vascular/patologia
2.
Cytopathology ; 24(6): 365-71, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-22994380

RESUMO

OBJECTIVE: The aim of this study was to compare liquid-based endometrial cytology with hysteroscopy and endometrial biopsy regarding its diagnostic accuracy in a series of postmenopausal women with abnormal uterine bleeding (AUB) or asymptomatic women with thickened endometrium assessed by transvaginal ultrasound as a screening procedure. METHODS: Inclusion criteria were: menopausal status; the presence of AUB and/or thickened endometrium assessed by ultrasound (cut-off 4 mm); a normal Papanicolaou (Pap) smear; and no adnexal pathology at ultrasound. Exclusion criteria were: previous endometrial pathology; and previous operative hysteroscopy. Of 768 postmenopausal women referred to our general gynaecology clinics, 121 fulfilled the inclusion criteria and were recruited to the trial. Twenty-one refused to participate. Cytological sampling was carried out by brushing the uterine cavity using the Endoflower device with no cervical dilation and the vial was processed using a ThinPrep® 2000 automated slide processor. The slides were stained using a Pap method. RESULTS: In 98 cases with histological biopsies, endometrial cytology detected five cases of endometrial carcinoma, 10 of atypical hyperplasia and 47 of non-atypical hyperplasia; 36 cases were negative. In two cases cytology was inadequate because of uterine cervical stenosis. Taking atypical hyperplasia or worse as a positive test and outcome, the diagnostic accuracy of the endometrial cytology was 93.5%, with a sensitivity of 92% and specificity of 95%, a positive predictive value of 73% and a negative predictive value of 99%. All the carcinomas were detected by cytology. Only 42% of women with a positive diagnosis were symptomatic. The cytological sampling was well tolerated by all patients. No complication was registered. CONCLUSIONS: Liquid-based endometrial cytology can be considered an useful diagnostic method in the detection of endometrial pathology as a first-line approach, particularly if associated with transvaginal ultrasound.


Assuntos
Citodiagnóstico/métodos , Hiperplasia Endometrial/diagnóstico , Hiperplasia Endometrial/patologia , Pós-Menopausa , Hemorragia Uterina/diagnóstico , Hemorragia Uterina/patologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Diagnóstico Diferencial , Hiperplasia Endometrial/diagnóstico por imagem , Feminino , Humanos , Histeroscopia , Pessoa de Meia-Idade , Fatores de Risco , Ultrassonografia , Hemorragia Uterina/diagnóstico por imagem
3.
J Hosp Infect ; 130: 122-130, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36202186

RESUMO

BACKGROUND: Limited data are currently available on the incidence rates and risk factors for bacterial sepsis and invasive fungal infections (IFIs) among neonates and infants undergoing major surgery. AIM: To assess the incidence of bacterial sepsis and IFI, fungal colonization, risk factors for sepsis, and mortality in neonates and infants aged <3 months undergoing major surgery. METHODS: A multicentre prospective study was conducted involving 13 level-3 neonatal intensive care units in Italy, enrolling all infants aged ≤3 months undergoing major surgery. FINDINGS: From 2018 to 2021, 541 patients were enrolled. During hospitalization, 248 patients had a bacterial infection, and 23 patients had a fungal infection. Eighty-four patients were colonized by fungal strains. Overall, in-hospital mortality was 2.8%, but this was higher in infected than in uninfected infants (P = 0.034). In multivariate analysis, antibiotic exposure before surgery, ultrasound-guided or surgical placement of vascular catheters, vascular catheterization duration, and gestational age ≤28 weeks were all associated with bacterial sepsis. The risk of IFI was markedly higher in colonized infants (odds ratio (OR): 8.20; P < 0.001) and was linearly associated with the duration of vascular catheterization. Fungal colonization in infants with abdominal surgery increased the probability of IFI 11-fold (OR: 11.1; P < 0.001). CONCLUSION: Preventive strategies such as early removal of vascular catheters and the fluconazole prophylaxis should be considered to prevent bacterial and fungal sepsis in infants undergoing abdominal surgery, and even more so in those with fungal colonization.


Assuntos
Infecções Fúngicas Invasivas , Micoses , Sepse , Recém-Nascido , Lactente , Humanos , Incidência , Estudos Prospectivos , Micoses/epidemiologia , Micoses/prevenção & controle , Infecções Fúngicas Invasivas/epidemiologia , Infecções Fúngicas Invasivas/tratamento farmacológico , Fatores de Risco , Sepse/epidemiologia , Sepse/tratamento farmacológico , Antifúngicos/uso terapêutico
4.
Anticancer Res ; 29(5): 1499-506, 2009 May.
Artigo em Inglês | MEDLINE | ID: mdl-19443357

RESUMO

BACKGROUND: Ductal intraepitelial neoplasia (DIN) represents a spectrum of disease that may progress from usual hyperplasia to ductal carcinoma in situ (DCIS) grade 3. The aim of the study was to asses the correlation between the DIN classification and the surgical treatment including sentinel lymph node biopsy (SLNB). PATIENTS AND METHODS: In this retrospective study, 229 patients with DIN had undergone conservative or radical surgical treatment and SLNB in cases of DIN1C-DIN3. RESULTS: Breast conservative surgery was the definitive treatment in 80% of the cases. The H&E evaluation of excised sentinel nodes was negative for metastatic disease; nevertheless the immunohistochemical (IHC) evaluation revealed the presence of metastatic cells in 6 patients (3.7%). CONCLUSION: In cases of DIN lesions SLNB is not indicated. The only reason SLNB should be considered is when there is an evidence of invasive foci at definitive histology or when radical mastectomy is proposed.


Assuntos
Neoplasias da Mama/classificação , Carcinoma Intraductal não Infiltrante/classificação , Adulto , Neoplasias da Mama/patologia , Neoplasias da Mama/cirurgia , Carcinoma Intraductal não Infiltrante/patologia , Carcinoma Intraductal não Infiltrante/cirurgia , Feminino , Humanos , Imuno-Histoquímica , Pessoa de Meia-Idade , Planejamento de Assistência ao Paciente , Biópsia de Linfonodo Sentinela
6.
Eur J Histochem ; 60(1): 2573, 2016 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-26972714

RESUMO

There is recent mounting evidence that nanoparticles may have enhanced toxicological potential in comparison to the same material in the bulk form. The aim of this study was to develop a new method for unmask asbestos nanofibers from Formalin-Fixed, Paraffin-Embedded tissue. There is an increasing amount of evidence that nanoparticles may enhance toxicological potential in comparison to the same material in the bulk form. The aim of this study was to develop a new method to unmask asbestos nanofibers from Formalin-Fixed Paraffin-Embedded (FFPE) tissue. For the first time, in this study we applied Energy Dispersive X-ray (EDX) microanalysis through transmission electron microscopy to demonstrate the presence of asbestos nanofibers in histological specimens of patients with possible occupational exposure to asbestos. The diagnostic protocol was applied to 10 randomly selected lung cancer patients with no history of previous asbestos exposure. We detected asbestos nanofibers in close contact with lung cancer cells in two lung cancer patients with previous possible occupational exposure to asbestos. We were also able to identify the specific asbestos iso-type, which in one of the cases was the same rare variety used in the workplace of the affected patient. By contrast, asbestos nanofibers were not detected in lung cancer patients with no history of occupational asbestos exposure. The proposed technique can represent a potential useful tool for linking the disease to previous workplace exposure in uncertain cases. Furthermore, Formalin-Fixed Paraffin-Embedded (FFPE) tissues stored in the pathology departments might be re-evaluated for possible etiological attribution to asbestos in the case of plausible exposure. Since diseases acquired through occupational exposure to asbestos are generally covered by workers' insurance in most countries, the application of the protocol used in this study may have also relevant social and economic implications.


Assuntos
Amianto , Neoplasias Pulmonares , Nanofibras/química , Exposição Ocupacional/efeitos adversos , Amianto/química , Amianto/toxicidade , Feminino , Humanos , Neoplasias Pulmonares/induzido quimicamente , Neoplasias Pulmonares/metabolismo , Neoplasias Pulmonares/patologia , Masculino
7.
Cell Death Dis ; 6: e1974, 2015 Nov 12.
Artigo em Inglês | MEDLINE | ID: mdl-26561783

RESUMO

Current hypothesis suggest that tumors can originate from adult cells after a process of 'reprogramming' driven by genetic and epigenetic alterations. These cancer cells, called cancer stem cells (CSCs), are responsible for the tumor growth and metastases. To date, the research effort has been directed to the identification, isolation and manipulation of this cell population. Independently of whether tumors were triggered by a reprogramming of gene expression or seeded by stem cells, their energetic metabolism is altered compared with a normal cell, resulting in a high aerobic glycolytic 'Warburg' phenotype and dysregulation of mitochondrial activity. This metabolic alteration is intricately linked to cancer progression.The aim of this work has been to demonstrate the possibility of differentiating a neoplastic cell toward different germ layer lineages, by evaluating the morphological, metabolic and functional changes occurring in this process. The cellular differentiation reported in this study brings to different conclusions from those present in the current literature. We demonstrate that 'in vitro' neuroblastoma cancer cells (chosen as experimental model) are able to differentiate directly into osteoblastic (by rapamycin, an mTOR inhibitor) and hepatic lineage without an intermediate 'stem' cell step. This process seems owing to a synergy among few master molecules, metabolic changes and scaffold presence acting in a concerted way to control the cell fate.


Assuntos
Células-Tronco Neoplásicas/efeitos dos fármacos , Células-Tronco Neoplásicas/patologia , Neuroblastoma/patologia , Inibidores de Proteínas Quinases/farmacologia , Serina-Treonina Quinases TOR/antagonistas & inibidores , Antibióticos Antineoplásicos/farmacologia , Diferenciação Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Humanos , Células K562 , Sirolimo/farmacologia
8.
Atherosclerosis ; 95(2-3): 191-9, 1992 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-1384519

RESUMO

The purpose of this study was to investigate the vasoformative behavior in vitro of the native intimal endothelium of the rat aorta. To visualize the intimal surface directly, thoracic aortas were everted using a procedure that sequestered adventitial cells and possible remnant microvessels of periaortic soft tissues inside the aortic tube. Everted aortas embedded in collagen gel and cultured under serum-free conditions generated branching microvessels by a process of sprouting from the aortic intima. The newly formed microvessels originated from patches of activated intimal endothelial cells, which had survived the mechanical damage of the eversion procedure. Activated endothelial cells crawled over each other and engaged in lumen formation forming bilayers or multilayers of cells which became the source of sprouting histotypic microvessels. The endothelium of the newly formed microvessels was positive for factor VIII-related antigen and was partially surrounded by periendothelial cells which expressed alpha-smooth muscle actin. The results of this study indicate that the intimal endothelium of the rat aorta has considerable functional plasticity and can switch to a vasoformative phenotype in response to changes in the surrounding extracellular matrix environment.


Assuntos
Aorta/fisiopatologia , Endotélio Vascular/fisiopatologia , Técnicas Histológicas , Neovascularização Patológica/fisiopatologia , Animais , Aorta/metabolismo , Aorta/patologia , Colágeno , Técnicas de Cultura , Endotélio Vascular/metabolismo , Géis , Imuno-Histoquímica , Masculino , Microcirculação , Microscopia Eletrônica , Neovascularização Patológica/genética , Neovascularização Patológica/metabolismo , Fenótipo , Ratos , Ratos Endogâmicos F344
9.
J Nucl Med ; 41(2): 242-9, 2000 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-10688106

RESUMO

UNLABELLED: Activated mononuclear cells expressing interleukin-2 (IL2) receptors (IL2-Rs) heavily infiltrate the Crohn's disease (CD) gut wall. A new technique for the in vivo detection of tissue infiltrating IL2-R positive (IL2R+ve) cells was developed based on 123I-IL2 scintigraphy. The aim of this study was to investigate whether 123I-IL2 accumulates in the CD gut wall in different phases of the disease and to evaluate the specificity of 123I-IL2 binding to activated IL2R+ve cells infiltrating the gut wall. METHODS: Fifteen patients with ileal CD (10 active and 5 inactive) and 10 healthy volunteers were studied by 123I-IL2 scintigraphy. Six patients with active CD were studied before and after 12 wk of steroid treatment. After scintigraphy, patients were followed up for 29-54 mo. Ex vivo autoradiography was performed to determine specificity of 125I-IL2 binding to IL2R+ve cells. For bowel scintigraphy, 123I-IL2 (75 MBq) was injected intravenously and gamma camera images were acquired after 1 h. Bowel radioactivity was quantified in 64 regions of interest (ROIs). RESULTS: Autoradiography showed specific binding of 125I-IL2 to IL2R+ve mononuclear cells infiltrating the CD gut wall. Intestinal 123I-IL2 uptake assessed by the number of positive ROIs was higher in patients with active or inactive CD than in healthy volunteers (P < 0.0001 and P = 0.03, respectively) and positively correlated with the CD activity index (P = 0.01). 123I-IL2 intestinal uptake significantly decreased in patients with CD in steroid-induced remission (P = 0.03). A significant correlation was observed between the number of positive ROIs and time to disease relapse. CONCLUSION: 123I-IL2 accumulates in the diseased CD gut wall by specific binding to IL2R+ve cells, infiltrating the involved tissues. 123I-IL2 scintigraphy may be an objective tool for the in vivo assessment of intestinal activated mononuclear cell infiltration.


Assuntos
Doença de Crohn/diagnóstico por imagem , Interleucina-2 , Radioisótopos do Iodo , Adulto , Autorradiografia , Estudos de Casos e Controles , Feminino , Humanos , Íleo/diagnóstico por imagem , Interleucina-2/farmacocinética , Masculino , Cintilografia , Receptores de Interleucina-2/metabolismo , Sensibilidade e Especificidade
10.
Drugs Aging ; 8(4): 275-98, 1996 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-8920175

RESUMO

The incidence of cardiovascular diseases that are related to the atherosclerotic process increases exponentially with age. Organ lesions, the clinical manifestation of atherosclerotic disease, are late events due to complications in the plaque (ulceration, thrombosis, calcification) which are the result of an increased vulnerability to disruption of a previously stable plaque. The higher incidence of age-related clinical events could be explained by a rising sensitivity of plaques to destabilising factors, both parietal and humoral. The increased probability that a plaque in an elderly patient will became vulnerable could be related to those destabilising factors that significantly increase with aging, such as advanced glycation end-products. For these reasons, it seems most important that the analysis of these age-related destabilising factors, rather than those factors that promote the development of early atherosclerotic plaques, should be undertaken. Taking the point of view of a pharmacological intervention, this should eventually lead to a more complete understanding of this process.


Assuntos
Artérias/fisiopatologia , Arteriosclerose/prevenção & controle , Arteriosclerose/fisiopatologia , Fatores Etários , Idoso , Arteriosclerose/etiologia , Humanos , Hiperlipidemias/complicações , Hipertensão/complicações , Fatores de Risco
11.
In Vitro Cell Dev Biol Anim ; 36(5): 336-40, 2000 May.
Artigo em Inglês | MEDLINE | ID: mdl-10937837

RESUMO

Type IV collagen is a major basement membrane component that has been implicated in the regulation of angiogenesis. The purpose of this study was to evaluate the effect of type IV collagen on the angiogenic response of native endothelial cells in three-dimensional vascular organ culture. Rings of rat aorta were cultured under serum-free conditions in gels of type I collagen with or without type IV collagen. In the absence of type IV collagen, aortic rings generated neovessels, which proliferated until day 9 and gradually regressed during the second and third weeks of culture. Type IV collagen promoted neovessel elongation and survival in a dose-dependent manner. Microvascular length increased by 43, 57, and 119% over control values in cultures treated with 3, 30, and 300 microg/ml type IV collagen, respectively. When used at high concentrations (300 microg/ml) type IV collagen stabilized the neovascular outgrowths and prevented vascular regression. Type IV collagen also promoted the formation of neovessels, but significant stimulatory effects were observed only at an intermediate concentration (30 microg/ml) and were no longer significant at the high concentration (300 microg/ml). The observation that type IV collagen has dose-dependent effects on vascular elongation, proliferation, and stabilization, supports the concept that the developing basement membrane of neovessels acts as a solid-phase regulator of angiogenesis, whose function varies depending on the concentration of its molecular components.


Assuntos
Aorta/efeitos dos fármacos , Colágeno/farmacologia , Neovascularização Fisiológica/efeitos dos fármacos , Animais , Aorta/fisiologia , Técnicas In Vitro , Camundongos , Modelos Biológicos , Ratos
12.
Nucl Med Commun ; 24(3): 305-16, 2003 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-12612472

RESUMO

We describe in detail the labelling of interleukin-2 with I ( I-IL2), its biochemical characterization, the binding assay and its use for the detection of tissues infiltrated with mononuclear cells. Human recombinant IL2 was labelled using an enzymatic method and its biochemical characterization was performed using high performance liquid chromatography (HPLC) analysis of cyanogen bromide-cleaved protein. biological and binding assays were performed on CTLL-2 cell line and on activated peripheral blood lymphocytes. studies were performed 1 h after administration of 2-3 mCi of I-IL2 in 10 newly diagnosed type 1 diabetes patients, five pre-diabetic patients, 10 Hashimoto's thyroiditis patients, 10 coeliac disease patients and 10 normal volunteers. I-IL2 scintigraphy allowed the detection and quantification of activated mononuclear cells in several affected tissues. In detail, I-IL2 accumulation was detected in the thyroid of all patients affected by Hashimoto's thyroiditis, in the bowel of all coeliac disease patients and in the pancreas of all pre-type 1 diabetic patients. By contrast, in newly diagnosed type 1 diabetics, I-IL2 scan was positive in five of the 10 studied patients. I-IL2 scintigraphy may be useful for studying autoimmune phenomena and in diagnostic protocols to evaluate the presence of other tissue involvement in patients with an organ-specific autoimmune disease.


Assuntos
Doenças Autoimunes/diagnóstico por imagem , Diabetes Mellitus/diagnóstico por imagem , Interleucina-2/farmacocinética , Radioisótopos do Iodo , Linfócitos/diagnóstico por imagem , Adolescente , Adulto , Sequência de Aminoácidos , Doença Celíaca/diagnóstico por imagem , Doença Celíaca/imunologia , Células Cultivadas , Criança , Diabetes Mellitus/imunologia , Diabetes Mellitus Tipo 1/diagnóstico por imagem , Feminino , Humanos , Interleucina-2/química , Marcação por Isótopo/métodos , Contagem de Linfócitos , Masculino , Dados de Sequência Molecular , Valores de Referência , Reprodutibilidade dos Testes , Tireoidite Autoimune/diagnóstico por imagem , Tomografia Computadorizada de Emissão de Fóton Único , Tomografia Computadorizada por Raios X
13.
J Exp Clin Cancer Res ; 19(4): 467-9, 2000 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-11277324

RESUMO

Treatment with 5-fluorouracil (5-FU) or recombinant interferon-gamma (IFN), alone or in combination, was found to increase carcinoembryonic antigen (CEA) expression in several carcinoma cell lines. In this study we examined the in vitro effect of these agents on CEA expression of tumor cells, obtained from a patient operated for rectal cancer. The results showed that exposure of cancer cells to 5-FU or to IFN resulted in increased CEA levels in terms of percentage of CEA-positive cells and mean fluorescence values, as indicated by FACS analysis. However, drug combination did not induce CEA expression higher than that provided by single agents alone. Treatment with 5-FU or with IFN produced a reduction of the total number of viable cells. Moreover, Western blot analysis revealed that exposure of cancer cells to each drug was followed by a substantial increase of the total cellular CEA content. On the contrary, 5-FU in combination with IFN did not increase the expression of the antigen more than that obtained by single agents. Noteworthy, exposure of CEA-negative cells from adjacent normal rectal tissue to both agents alone or in combination, did not result in CEA induction. In conclusion, the present results suggest new approaches aimed at (a) increasing the sensitivity of diagnostic procedures based on detection of CEA-positive tumor cells; (b) facilitating the recognition of CEA-positive cancer cells by immune responses induced by anti-CEA peptide vaccines.


Assuntos
Antígeno Carcinoembrionário/metabolismo , Fluoruracila/farmacologia , Interferon gama/farmacologia , Neoplasias Retais/metabolismo , Adulto , Antígeno Carcinoembrionário/sangue , Feminino , Citometria de Fluxo , Humanos , Proteínas Recombinantes , Neoplasias Retais/patologia , Neoplasias Retais/cirurgia , Células Tumorais Cultivadas
14.
Surg Neurol ; 56(4): 242-6, 2001 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-11738672

RESUMO

BACKGROUND: Solitary fibrous tumor (SFT), which usually presents in the pleura and is thought to be mesothelial in nature, has been recently discovered in extrapleural sites, including the orbit. Presently ultrastructural studies show absence of epithelial-mesothelial features, and reactivity of the tumor cells to CD34 antigen on immunohistochemical analysis suggests the mesenchymal origin of such tumors. CASE DESCRIPTION: A 40-year-old woman had a 4-year history of progressive swelling of her right upper lid and a slow-growing palpable mass of the orbit. CT and MR imaging showed a well circumscribed, nonenhanced extraconal mass with mild erosion of the right orbital roof. The tumor was totally excised. Histological examination disclosed a spindle-cell tumor in a dense fibrous tissue. Immunohistochemistry showed positive staining for vimentin and CD34. We review the clinical, diagnostic, and surgical features of 22 orbital SFTs including the present case. CONCLUSIONS: Orbital SFT generally pursues a slow, indolent, and nonaggressive course, reaches a size up to 4.5 cm, and can be cured by a single excision. It must be immunohistochemically differentiated from other spindle-cell tumors of the orbit.


Assuntos
Neoplasias de Tecido Fibroso/diagnóstico , Neoplasias Orbitárias/diagnóstico , Adulto , Antígenos CD34/metabolismo , Feminino , Humanos , Imuno-Histoquímica , Neoplasias de Tecido Fibroso/metabolismo , Neoplasias de Tecido Fibroso/patologia , Neoplasias de Tecido Fibroso/cirurgia , Neoplasias Orbitárias/metabolismo , Neoplasias Orbitárias/patologia , Neoplasias Orbitárias/cirurgia , Vimentina/metabolismo
15.
Eur J Histochem ; 48(2): 103-10, 2004.
Artigo em Inglês | MEDLINE | ID: mdl-15208076

RESUMO

Somatostatin is a peptide hormone that exerts antisecretory and antiproliferative activities on some human tumors. The Ku70/86 heterodimer acts as regulatory subunit of the DNA dependent protein kinase and its DNA binding activity mediates DNA double strands breaks repair that is crucial to maintain the genetic integrity of the genome. The activation of the heterodimer regulates cell cycle progression and the activity of nuclear transcription factors involved in DNA replication and cell proliferation. Moreover Ku86 behaves as a receptor for the growth inhibitory tetradecapeptide, somatostatin. Herein we report that somatostatin treatment to a colon carcinoma cell line (Caco-2) inhibits cell growth and, at same time, strongly modulates the activation of Ku70/86 heterodimer and the levels of Ku86 in the nucleus by increasing its specific mRNA level. Our findings are consistent with the hypothesis that somatostatin controls cell cycle progression and DNA repair through a new signalling pathway that involves the regulation of Ku86 level and modulates the Ku70/86 activity in the nucleus.


Assuntos
Antígenos Nucleares/genética , Antígenos Nucleares/metabolismo , Núcleo Celular/metabolismo , Proteínas de Ligação a DNA/genética , Proteínas de Ligação a DNA/metabolismo , Somatostatina/farmacologia , Antígenos Nucleares/efeitos dos fármacos , Divisão Celular/efeitos dos fármacos , Divisão Celular/fisiologia , Linhagem Celular Tumoral , DNA/efeitos dos fármacos , DNA/metabolismo , Proteínas de Ligação a DNA/efeitos dos fármacos , Dimerização , Humanos , Imuno-Histoquímica , Autoantígeno Ku , RNA Mensageiro/efeitos dos fármacos , RNA Mensageiro/metabolismo
16.
Eur J Histochem ; 44(3): 237-46, 2000.
Artigo em Inglês | MEDLINE | ID: mdl-11095095

RESUMO

U937 cells induced to apoptosis, progressively and dramatically modified their cell shape by intense blebbing formation, leading to the production of apoptotic bodies. The blebs evolved with time; milder forms of blebbing involving only a region or just the cortical part of the cytoplasm were observed within the first hour of incubation with puromycin; blebbing involving the whole cell body with very deep constrictions is the most frequent event observed during late times of incubation. The ultrastructural analysis of apoptotic cells revealed characteristic features of nuclear fragmentation (budding and cleavage mode) and cytoplasmatic modifications. The cytoplasm of blebs does not contain organelles, such as ribosomes or mitochondria. Scarce presence of endoplasmic reticulum can be observed at the site of bleb detachment. However, blebbing is a dispensable event as evaluated by using inhibitor of actin polymerization. In the present study, the progressive modifications of the nucleus, mitochondria, nuclear fragmentation, cytoplasmic blebs formation and production of apoptotic bodies in U937 monocytic cells induced to apoptosis by puromycin (an inhibitor of protein synthesis) were simultaneously analyzed.


Assuntos
Apoptose , Tamanho Celular/fisiologia , Organelas/fisiologia , Organelas/ultraestrutura , Apoptose/efeitos dos fármacos , Núcleo Celular/ultraestrutura , Retículo Endoplasmático/ultraestrutura , Humanos , Microscopia Eletrônica de Varredura , Organelas/efeitos dos fármacos , Puromicina/farmacologia , Células U937
17.
Eur J Histochem ; 46(1): 61-74, 2002.
Artigo em Inglês | MEDLINE | ID: mdl-12044049

RESUMO

In this study we investigated the relationship between nuclear and cell surface modifications (i.e. blebbing, phosphatidylserine [PS] and sugar residues exposure) in a monocytic cell line, U937, during apoptosis induced by oxidative stress (1 mM H2O2) or inhibition of protein synthesis (10 microg/ml puromycin). Dying cells were simultaneously observed for nuclear modifications, presence of superficial blebs and plasma membrane alterations. Morphological analysis performed by conventional fluorescence microscopy, or by transmission and scanning electron microscopy showed that the courses of nuclear and membrane alterations occured concomitantly, but the phenotype was dependent on the stage of the apoptotic process and the type of apoptogenic inducer used. The progression of apoptosis in U937 cells beyond early stages resulted in the extensive formation of blebs which concomitantly lost some typical markers of apoptosis, such as PS and sugar residues. Therefore, the modality by which the nucleus condenses, or the amount and the pattern of distribution of PS on the cell surface were, for each cell line, strictly related to the apoptogenic inducer. The morphological data reported in the present paper should lead to a more precise quantification of apoptosis by improving the detection of apoptotic cells in vivo (i.e. in tissue, organs), which is a crucial point in the evaluation of efficiency of antiproliferative drugs, such as antiblastic or immunosuppressive compounds.


Assuntos
Apoptose/fisiologia , Núcleo Celular/ultraestrutura , Extensões da Superfície Celular/ultraestrutura , Apoptose/efeitos dos fármacos , Núcleo Celular/efeitos dos fármacos , Tamanho Celular/efeitos dos fármacos , Extensões da Superfície Celular/efeitos dos fármacos , Fragmentação do DNA/efeitos dos fármacos , Humanos , Peróxido de Hidrogênio/farmacologia , Microscopia Eletrônica de Varredura , Puromicina/farmacologia , Fatores de Tempo , Células U937
18.
Int Angiol ; 7(1): 75-80, 1988.
Artigo em Inglês | MEDLINE | ID: mdl-3290360

RESUMO

The positive correlation between cerebral ischemia and carotid atherosclerosis of extracranial tract has been well established. The reliability of echotomography as diagnostic and prognostic tool in the evaluation of the carotid atherosclerotic lesions is now intensively investigated. Most of the attention has been payed to the accuracy in the determination of the carotid stenosis. A percentage of cerebrovascular accidents do not correlate to the vascular stenosis but to the other modifications induced by the atherosclerotic plaque, such as the release of emboli, acute stenosis for intraplaque haemorrhage or thrombosis. Thus the evaluation of the composition of the plaque may represent a good prognostic tool. In the present study, fifty-two carotid obtained at surgery from patients, who preoperatively underwent ultrasonographic scanning of both carotid arteries, were examined by histological methods. In calcified tissues a significant correlation between findings obtained with both techniques was observed. In the complicated plaques atheromasic gruel, intraplaque haemorrhages and thrombosis could not be discriminated by echotomography.


Assuntos
Artérias Carótidas/patologia , Doenças das Artérias Carótidas/diagnóstico , Arteriosclerose Intracraniana/diagnóstico , Ultrassonografia , Doenças das Artérias Carótidas/patologia , Humanos , Arteriosclerose Intracraniana/patologia
19.
Int Angiol ; 8(4): 216-23, 1989.
Artigo em Inglês | MEDLINE | ID: mdl-2699484

RESUMO

The ultrasound image of the fibroatheromatous plaque has to date been unable to reveal the presence or absence of complications as shown by histology, such as thrombosis and intraplaque hemorrhage. We propose a novel densitometric method for determining the composition of the plaque at the echotomography, along with a new classification based on mathematical models drawn from the optical density distribution curve. This approach avails of an extremely high sensitivity. Percent areas occupied by thrombosis, intraplaque hemorrhage and atheroma in histologic sections have been shown to correspond to hyporeflecting areas in echotomographic images, whereas those occupied by calcium and fibrous tissue correspond to reflecting areas with or without acoustic shadow, respectively. This method may prove to have an important role in the non-invasive monitoring of even slight changes during progression or regression of the fibroatheromatous plaque.


Assuntos
Arteriosclerose/diagnóstico , Doenças das Artérias Carótidas/diagnóstico , Densitometria , Ultrassonografia/métodos , Humanos
20.
Arch Gerontol Geriatr ; 22 Suppl 1: 423-8, 1996.
Artigo em Inglês | MEDLINE | ID: mdl-18653071

RESUMO

The response of human red blood cells (RBC) to oxidative stress has been studied with the aim to evaluate any difference in the behavior of cells from young and old subjects. Thus, RBC from 5 young (27 +/- 2 years) and 5 old (80 +/- 5 years) individuals have been treated with the organic peroxide t-butyl hydroperoxide (TBHP). The two groups behaved differently: after 4 hrs of incubation in 0.5 mM TBHP, RBC from young donors showed a higher level of hemolysis; instead, RBC from old individuals showed abnormal morphologies, being absent in unstressed RBC, with constriction and budding, which could be identified as poikilocytosis. The same abnormal forms are found in patients with spectrin mutation, leading us to hypothesize that TBHP causes damage to the cytoskeletal spectrin. This suggests that poikilocytosis might be an early stage of red blood cell hemolysis because their presence is associated to a lower level of hemolysis.

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