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1.
Chemosphere ; 269: 128748, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33139043

RESUMO

Two new adsorbents, namely avocado-based hydrochar and LDH/bone-based biochar, were developed, characterized, and applied for adsorbing 2-nitrophenol. The pore volume and surface diffusion model (PVSDM) was numerically solved for different geometries and applied to interpret the adsorption decay curves. Both adsorbents presented interesting textural and physicochemical characteristics, which achieved maximum adsorption capacities of 761 mg/g for biochar and 562 mg/g for hydrochar. The adsorption equilibrium data were well fitted by Henry isotherm. Besides, thermodynamic investigation revealed endothermic adsorption with the occurrence of electrostatic interactions. PVSDM predicted the adsorption decay curves for different adsorbent geometries at different initial concentrations of 2-nitrophenol. The surface diffusion was the main intraparticle mass transport mechanism. Furthermore, the external mass transfer and surface diffusion coefficients increased with the increase of 2-nitrophenol concentration.


Assuntos
Poluentes Químicos da Água , Adsorção , Carvão Vegetal , Concentração de Íons de Hidrogênio , Cinética , Nitrofenóis , Soluções , Termodinâmica
2.
High Blood Press Cardiovasc Prev ; 27(2): 121-128, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32157643

RESUMO

The latest European Guidelines of Arterial Hypertension have officially introduced uric acid evaluation among the cardiovascular risk factors that should be evaluated in order to stratify patient's risk. In fact, it has been extensively evaluated and demonstrated to be an independent predictor not only of all-cause and cardiovascular mortality, but also of myocardial infraction, stroke and heart failure. Despite the large number of studies on this topic, an important open question that still need to be answered is the identification of a cardiovascular uric acid cut-off value. The actual hyperuricemia cut-off (> 6 mg/dL in women and 7 mg/dL in men) is principally based on the saturation point of uric acid but previous evidence suggests that the negative impact of cardiovascular system could occur also at lower levels. In this context, the Working Group on uric acid and CV risk of the Italian Society of Hypertension has designed the Uric acid Right for heArt Health project. The primary objective of this project is to define the level of uricemia above which the independent risk of CV disease may increase in a significantly manner. In this review we will summarize the first results obtained and describe the further planned analysis.


Assuntos
Doenças Cardiovasculares/epidemiologia , Hiperuricemia/epidemiologia , Ácido Úrico/sangue , Adulto , Idoso , Biomarcadores/sangue , Doenças Cardiovasculares/sangue , Doenças Cardiovasculares/mortalidade , Feminino , Humanos , Hiperuricemia/sangue , Hiperuricemia/diagnóstico , Hiperuricemia/mortalidade , Itália/epidemiologia , Masculino , Pessoa de Meia-Idade , Estudos Multicêntricos como Assunto , Estudos Observacionais como Assunto , Prognóstico , Projetos de Pesquisa , Estudos Retrospectivos , Medição de Risco , Fatores de Risco , Fatores de Tempo
3.
J Colloid Interface Sci ; 560: 722-729, 2020 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-31706654

RESUMO

Chitosan-based hybrid hydrogels such as chitosan hydrogel (CH), chitosan hydrogel with activated carbon (CH-AC), scaffold-chitosan hydrogel (SCH), scaffold-chitosan hydrogel with activated carbon (SCH-AC) and scaffold-chitosan hydrogel with carbon nanotubes (SCH-CN) were synthesized, characterized and applied to adsorb Acid Blue 9 (AB) and Allura Red AC (AR) from single and simultaneous binary liquid systems. Experimental results revealed competitive adsorption as the adsorption capacity was reduced in binary system for each dye. In addition, SCH-CN presented the highest adsorption capacity for both dyes, indicating that the modification increased the number of active sites and the functionalization with OH groups favored the interactions with sulfonated groups of the dyes. A predictive artificial neural network (ANN) was implemented to forecast the adsorption capacity for AB and AR dyes as a function of initial molar concentration of each dye, adsorption time, porosity and mass percentage of carbonaceous material on each hydrogel. The network was trained with the Levenberg-Marquardt back-propagation optimization, and according to the high correlation coefficient (R = 0.9987) and low values of root mean square error (RMSE = 0.0119), sum of the absolute error (SAE = 0.7541) and sum of squares error (SSE = 0.0132), the best topology was found to be 5-10-10-10-2. The ANN proved to be effective in predicting dye adsorption capacity of each hydrogel, even for the competitive adsorption, as the R values were close to unity for all simulation systems.


Assuntos
Compostos Azo/química , Benzenossulfonatos/química , Quitosana/química , Corantes/química , Hidrogéis/química , Nanotubos de Carbono/química , Redes Neurais de Computação , Adsorção , Ligação Competitiva , Carvão Vegetal/química
4.
Thromb Res ; 136(2): 225-8, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-26033396

RESUMO

INTRODUCTION: The relationship between metabolic syndrome (MetS), and the development of post-thrombotic syndrome (PTS) is currently unknown. MATERIALS AND METHODS: We enrolled 120 patients with a previous episode of deep venous thrombosis (DVT) diagnosed more than 2years apart from the enrollment. Presence of MetS was identified according to NCEP ATP III criteria and Villalta Score (VS) was used to establish the presence of PTS (VS≥5). RESULTS: We identified 49 (40.8%) subjects with clinical diagnosed of PTS. Patients with or without PTS showed comparable age and temporal distance from DVT event. We observed higher BMI (p=0.005) and waist circumference (p=0.006) among subjects with VS≥5 as compared to patients without PTS. No differences between the two groups were found in terms of lipid profile, blood pressure, diabetes, hs-CRP level and ongoing medications. The prevalence of MetS was equally distributed among patients with or without PTS (20% vs 26% respectively, p=0.64). Among the individual components of MetS only the prevalence of visceral adiposity was significantly increased in subjects affected by PTS (OR 2.81, p=0.008). Moreover, a significant linear correlation was found between VS and waist circumference in the entire cohort (r=0,354, p<0.0001). CONCLUSION: There is no evidence of association between MetS and PTS. However, the degree of visceral adiposity is strongly correlated with the presence and severity of post-thrombotic disease.


Assuntos
Síndrome Metabólica/complicações , Obesidade Abdominal/complicações , Síndrome Pós-Trombótica/etiologia , Tromboembolia Venosa/etiologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Fatores de Risco , Circunferência da Cintura
5.
J Hum Hypertens ; 29(9): 561-5, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-25518897

RESUMO

We evaluated the structural/functional characteristics of the arterial wall in a cohort of hypertensives with well-controlled blood pressure (BP) levels. We studied 40 hypertensives with well-controlled BP. We assessed by B-mode ultrasound the mean intima-media thickness (mean-IMT) and maximum-IMT (M-MAX) of carotid artery (common, bulb, internal) bilaterally. Endothelial function was evaluated by post-occlusion flow-mediated dilation (FMD) of the brachial artery. Along with traditional risk factors, we studied the impact of serum high-sensitivity C-reactive protein (hs-CRP) and osteoprotegerin (OPG). Forty normotensive subjects served as controls. In the hypertensives, the BP levels were well controlled (office BP: 129/79 mm Hg, ambulatory BP monitoring: 121/75 mm Hg). Compared with controls, higher BP levels and body mass index were present in hypertensives, whereas age and metabolic parameters were similar. In hypertensives, the IMT (mean-IMT 0.68 mm, M-MAX 0.81 mm) was significantly higher than in controls (mean-IMT 0.60 mm, M-MAX 0.71 mm). FMD was impaired in hypertensives (5.9%) compared with controls (9.2%). In multivariate analyses, it turned out that in hypertensives IMT parameters were related to age, hs-CRP and OPG. Low-density lipoprotein (LDL) cholesterol was the only factor related to FMD. IMT and FMD had no relationship with BP levels. In conclusion, in hypertensives with well-controlled BP, the pro-atherogenic remodelling (IMT) is mainly dependent on age and the inflammatory cytokines, OPG in particular. The functional impairment of the arterial wall (FMD) was related to the levels of LDL cholesterol. Under these conditions, when the impact of BP is minimized, the role of inflammatory cytokines and lipids on structural/functional remodelling becomes predominant.


Assuntos
Anti-Hipertensivos/uso terapêutico , Pressão Sanguínea/efeitos dos fármacos , Artéria Braquial/efeitos dos fármacos , Artéria Carótida Primitiva/efeitos dos fármacos , Hipertensão/tratamento farmacológico , Remodelação Vascular/efeitos dos fármacos , Vasodilatação/efeitos dos fármacos , Adulto , Biomarcadores/sangue , Artéria Braquial/diagnóstico por imagem , Artéria Braquial/metabolismo , Artéria Braquial/fisiopatologia , Proteína C-Reativa/análise , Artéria Carótida Primitiva/diagnóstico por imagem , Artéria Carótida Primitiva/metabolismo , Artéria Carótida Primitiva/fisiopatologia , Espessura Intima-Media Carotídea , Estudos de Casos e Controles , LDL-Colesterol/sangue , Feminino , Humanos , Hipertensão/sangue , Hipertensão/diagnóstico por imagem , Hipertensão/fisiopatologia , Mediadores da Inflamação/sangue , Masculino , Pessoa de Meia-Idade , Osteoprotegerina/sangue , Valor Preditivo dos Testes , Estudos Prospectivos , Resultado do Tratamento
6.
J Hum Hypertens ; 28(2): 105-10, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-23842084

RESUMO

We studied the impact of hypertension along with traditional and new cardiovascular risk factors on the structural and functional properties of arteries in psoriatic arthritis (PsA) patients. We examined 42 PsA subjects (aged 51±9 years) stratified according to hypertensive status (19 normotensive, PsA-NT and 23 hypertensives, PsA-HT). Thirty-eight normotensive subjects (C-NT) and 23 hypertensives (C-HT) comparable by age and sex served as controls. Mean carotid intima-media thickness (mean-IMT) and mean of the maximum IMT (M-Max) were evaluated by ultrasound in carotid artery segment bilaterally. Post-occlusion flow-mediated dilation (FMD) of the brachial artery was evaluated by ultrasonography. These parameters were correlated with risk factors, markers of inflammation and disease activity. Values of mean-IMT were higher in both groups of PsA patients compared with C-NT (0.68 mm in PsA-NT and 0.75 mm in PsA-HT versus 0.61 mm in C-NT). PsA-HT displayed higher M-Max (0.95 mm) versus both C-HT (0.71 mm) and PsA-NT (0.79 mm). FMD was impaired in PsA subjects compared with C-NT (5.7% in PsA-NT and 6.0% PsA-HT versus 9.3% in C-NT), whereas there was no difference among PsA-HT, PsA-NT, and C-HT groups. Values of carotid IMT were directly related to tumor necrosis factor (TNF)-α, osteoprotegerin (OPG), blood pressure and lipid profile levels. FMD showed an inverse relationship with TNF-α and blood pressure, but no correlation with lipids. In conclusion, PsA per se implies a pro-atherogenic remodeling, which is enhanced by the hypertensive status. TNF-α and OPG may have an independent role in the development of such vascular damage.


Assuntos
Artrite Psoriásica/complicações , Artéria Braquial/fisiopatologia , Artérias Carótidas , Doenças das Artérias Carótidas/complicações , Hipertensão/complicações , Vasodilatação , Adulto , Artrite Psoriásica/sangue , Artrite Psoriásica/diagnóstico , Biomarcadores/sangue , Artéria Braquial/diagnóstico por imagem , Artérias Carótidas/diagnóstico por imagem , Doenças das Artérias Carótidas/diagnóstico , Doenças das Artérias Carótidas/fisiopatologia , Espessura Intima-Media Carotídea , Estudos de Casos e Controles , Feminino , Humanos , Hipertensão/diagnóstico , Hipertensão/fisiopatologia , Mediadores da Inflamação/sangue , Masculino , Pessoa de Meia-Idade , Osteoprotegerina/sangue , Valor Preditivo dos Testes , Fatores de Risco , Fator de Necrose Tumoral alfa/sangue
8.
Angiology ; 58(5): 565-71, 2007.
Artigo em Inglês | MEDLINE | ID: mdl-18024939

RESUMO

Carotid stenting is an alternative to endarterectomy for the treatment of carotid stenosis. To determine the role of vascular remodeling after stent placement, we studied 19 high surgical risk patients undergoing carotid stenting for severe stenosis. Using high-resolution ultrasound, we evaluated the intima-media thickness (IMT), the intima-intima diameter, and the adventitia-adventitia diameter at prespecified sites of the carotid artery tree during 3 years of follow-up. The IMT of internal carotid artery, at the site of maximum stenosis, increased significantly from 0 mm after 24 hours, to 0.41 mm at 3 months, to 0.48 mm at 6 months, and to 0.51 mm at 3 years of follow-up. In the same site, diameters and residual stenosis (range 29-24%) did not change over time. Our study showed that stent is self-expanding against the atherosclerotic plaque within the 3-year follow-up period. Despite neointima formation, the intima-intima diameter does not change without worsening of the residual stenosis.


Assuntos
Angioplastia Coronária com Balão , Artéria Carótida Interna/diagnóstico por imagem , Estenose das Carótidas/terapia , Reestenose Coronária/diagnóstico por imagem , Ecocardiografia Doppler , Stents , Idoso , Idoso de 80 Anos ou mais , Angioplastia Coronária com Balão/efeitos adversos , Angioplastia Coronária com Balão/instrumentação , Estenose das Carótidas/diagnóstico por imagem , Tecido Conjuntivo/diagnóstico por imagem , Angiografia Coronária , Reestenose Coronária/etiologia , Estudos de Viabilidade , Seguimentos , Humanos , Pessoa de Meia-Idade , Índice de Gravidade de Doença , Fatores de Tempo , Resultado do Tratamento , Túnica Íntima/diagnóstico por imagem , Túnica Média/diagnóstico por imagem
10.
Aliment Pharmacol Ther ; 22 Suppl 2: 20-3, 2005 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-16225466

RESUMO

The atherosclerotic process is regulated by inflammatory mechanisms, which also appear to be involved in the modulation of insulin-resistance, a key player in the pathogenesis of the metabolic syndrome (MS). The interaction between components of the clinical phenotype of the MS with its biological phenotype (insulin resistance, dyslipidaemia, etc.) contributes to the development of a pro-inflammatory state characterized by an increased oxidative stress (i.e. oxidized lipoproteins) and a chronic, subclinical vascular inflammation, as also suggested by the increased C reactive protein (CRP) concentration found in patients with MS. The subclinical inflammatory state peculiar of the MS modulates the atherosclerotic process at different stages, resulting in: (i) endothelial dysfunction and increased expression of endothelial adhesion molecules; (ii) an enhanced recruitment of monocytes within the arterial wall, in the early stages of the atherosclerotic process; leading to (iii) the formation of an unstable atherosclerotic plaque, rich in inflammatory cells, which is the culprit lesion in the vast majority of both coronary and cerebrovascular events observed in with MS.


Assuntos
Aterosclerose/fisiopatologia , Síndrome Metabólica/fisiopatologia , Aterosclerose/complicações , Aterosclerose/metabolismo , Biomarcadores/análise , Proteína C-Reativa/análise , Moléculas de Adesão Celular/análise , Doença Crônica , Endotélio Vascular/fisiopatologia , Humanos , Inflamação/complicações , Inflamação/metabolismo , Inflamação/fisiopatologia , Lipoproteínas/metabolismo , Síndrome Metabólica/complicações , Síndrome Metabólica/metabolismo , Modelos Biológicos , Monócitos/fisiologia , Estresse Oxidativo/fisiologia
11.
Lupus ; 14(9): 747-51, 2005.
Artigo em Inglês | MEDLINE | ID: mdl-16218480

RESUMO

Atherosclerosis is recognized as the pathological basis of cardiovascular disease (CVD) and recent advances in basic science have shown that it should be considered as a chronic inflammatory process. Both elements of the innate and the adaptive immunity appear to be actively involved in atherogenesis. In fact, the potential role played by pattern-recognition receptors (Toll-like receptors and scavenger receptors), cytokines (such as IL-1, IL-6, TNFalpha), chemokines and pentraxines (such as CRP and PTX3) represents an emerging field of investigation in atherogenesis. In the near future we expect a better definition of the real biological and clinical impact on CVD of these mediators. On one side, they could become useful to complement traditional risk factors, in order to identify new categories of subjects prone to CVD development. On the other, they could become an additional potential target for therapeutic strategies.


Assuntos
Aterosclerose/imunologia , Imunidade Inata/fisiologia , Proteínas de Fase Aguda/imunologia , Proteína C-Reativa/imunologia , Citocinas/imunologia , Humanos , Receptores de Reconhecimento de Padrão/imunologia , Componente Amiloide P Sérico/imunologia
12.
Rheumatology (Oxford) ; 44(4): 484-7, 2005 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-15598706

RESUMO

OBJECTIVES: We report a female patient suffering from Takayasu arteritis (TA) who underwent surgical revascularization. METHODS: By studying specimens obtained at surgery, we evaluated the cell composition of the arterial wall, along with the maturation pattern of vascular smooth muscle cells (VSMC) during the active phase of TA. Using TUNEL, we detected apoptotic cells within the tunica media. RESULTS: The highest percentage of apoptotic cells was found in areas where inflammatory infiltrate was present and the medial structure was more or less damaged. Apoptotic cells were also found in structurally preserved areas, where VSMC but not inflammatory cells were present. CONCLUSIONS: Apoptosis involved not only inflammatory cells but also VSMC, particularly those of the immature type. We hypothesize a role for VSMC apoptosis in the development of TA.


Assuntos
Apoptose , Músculo Liso Vascular/patologia , Miócitos de Músculo Liso/patologia , Arterite de Takayasu/patologia , Adulto , Aorta Abdominal/patologia , Feminino , Humanos , Túnica Média/patologia
13.
J Vasc Surg ; 38(6): 1390-5, 2003 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-14681646

RESUMO

PURPOSE: We investigated whether differences in cellular composition of the shoulder region of carotid plaque, a cell-rich, debris-free area, can be revealed with computer-driven analysis of ultrasound scans. METHODS: In 26 patients referred for carotid endarterectomy, the shoulder region of plaque eligible for surgical removal was identified with ultrasound scanning. Digital images were obtained and evaluated with a specially developed computer-driven system (Medical Image Processing [MIP]). The gray level distribution of the region of interest (ROI), along with some statistical parameters exploring the spatial distribution of pixels, such as entropy and second angular moment, were analyzed. In the specimen retrieved at surgery, the area corresponding to the ROI was selected. Cryosections were tested at immunocytochemistry with monoclonal antibodies specific to smooth muscle cells (SMCs), macrophages), and lymphocytes. Computerized image analysis was performed to quantify each cellular component of the lesion. RESULTS: Mean gray levels were related positively to the content of SMCs (r = 0.576, P =.002) and negatively to the content of macrophages (r = -0.555, P =.003). Lymphocytes did not show any correlation. Prevalence of SMCs, expressed as the ratio SMC/(SMC + macrophages), was related positively with entropy (r = 0.517, P =.007) and negatively with the second angular moment (r = -0.422, P =.032). The quartiles of gray level were useful for detecting significant differences in terms of cellular composition. CONCLUSIONS: Some cellular features of the shoulder region of plaque are associated with specific videodensitometric patterns evaluated with MIP. This approach enables in vivo noninvasive prediction and monitoring of cell composition of the shoulder region, and could be extended to study of the thickened intima.


Assuntos
Estenose das Carótidas/patologia , Processamento de Imagem Assistida por Computador/métodos , Imuno-Histoquímica/métodos , Túnica Íntima/diagnóstico por imagem , Estenose das Carótidas/metabolismo , Estruturas Celulares/diagnóstico por imagem , Estruturas Celulares/metabolismo , Estudos de Viabilidade , Humanos , Miócitos de Músculo Liso/diagnóstico por imagem , Miócitos de Músculo Liso/metabolismo , Túnica Íntima/metabolismo , Ultrassonografia/métodos
14.
Ann Rheum Dis ; 62(11): 1071-7, 2003 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-14583570

RESUMO

OBJECTIVE: To evaluate traditional and non-traditional risk factors for subclinical atherosclerosis in systemic lupus erythematosus (SLE). METHODS: A prospective cohort of 78 patients with SLE without overt atherosclerotic disease was studied. SLE clinical and laboratory parameters, disease activity and damage, treatment and traditional risk factors for atherosclerosis were evaluated. At baseline (T1) and after five years' follow up (T2), the serum levels of anti-oxidised palmitoyl arachidonoyl phosphocholine (oxPAPC), anti-heat shock protein 65, and anti-beta(2)-glycoprotein I antibodies and C reactive protein were tested. At T2, intima-media thickness (IMT) was measured using duplex carotid sonography. Thickened intima, plaque, mean IMT (m-IMT), and maximum IMT (M-IMT) were assessed. RESULTS: A thickened intima was seen in 22/78 (28%) patients and plaque in 13/78 (17%). M-IMT and m-IMT were (mean (SD)) 0.77 (0.34) mm and 0.55 (0.15) mm, respectively. Patients with carotid abnormalities were significantly older, had higher blood pressure and total serum cholesterol levels, and had taken a higher prednisone cumulative dosage than those without any lesions. The carotid abnormalities were associated with renal disease and ECLAM >2 at T1, and with azathioprine treatment. In multivariate analysis, age and cumulative prednisone dose were associated with carotid abnormalities; age, hypertension, and anti-oxPAPC at T2 were correlated with higher M-IMT and m-IMT. CONCLUSIONS: In patients with SLE some non-traditional risk factors for atherosclerosis were identified, the most important of which was the cumulative prednisone dose. The role of some traditional risk factors, such as age and hypertension, was also confirmed. The predictive value of the new immunological and inflammatory markers of atherosclerosis seems to be masked by some disease related features.


Assuntos
Arteriosclerose/complicações , Arteriosclerose/diagnóstico , Lúpus Eritematoso Sistêmico/complicações , Adulto , Fatores Etários , Anti-Inflamatórios/uso terapêutico , Artérias Carótidas/patologia , Estudos Transversais , Feminino , Seguimentos , Humanos , Hipertensão/patologia , Lúpus Eritematoso Sistêmico/tratamento farmacológico , Nefrite Lúpica/patologia , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Prednisona/uso terapêutico , Estudos Prospectivos , Fatores de Risco , Túnica Íntima/patologia , Ultrassonografia Doppler Dupla
15.
J Endocrinol Invest ; 26(4): 359-63, 2003 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-12841545

RESUMO

Somatostatin receptors are highly expressed in almost all meningiomas but in this setting their functional role is not clear. A 59-yr-old woman had been treated with octreotide after an unsuccessful operation for a GH-secreting pituitary adenoma. After 8 yr of treatment, a nuclear magnetic resonance (NMR) scan disclosed a 3 cm meningioma of the tentorium. Mean GH was 2.2 ng/ml and IGF-I 325 ng/ml. Meningioma was resected and tissue was digested to obtain tumor cell suspension. Aim of the study was to measure epidermal growth factor (EGF)-induced proliferation of cultured meningioma cells in the presence of either somatostatin or octreotide. Cells were grown to semiconfluency in Dolbecco's modified eagle medium (D-MEM) supplemented with 10% fetal calf serum (FCS). After 48 h in D-MEM without serum, the medium was replaced by fresh medium plus recombinant EGF (10 ng/ml) and somatostatin or octreotide were added in the final concentrations of 1, 10 and 100 nM. 20 h later 1 microcgCi of 3H-thymidine was added to each well. After 4 h, incorporated radioactivity was measured. While octreotide did not influence significantly cell growth at the three dose tested, somatostatin increased thymidine incorporation dose-dependently (peak 100 nM: 150% +/- 27% vs medium plus EGF, p<0.05). Octreotide effectively suppressed GH secretion in our acromegalic patient but is unlikely that its long-term use could have stimulated the growth of meningioma since it did not significantly influence the in vitro proliferation of the meningioma cells. These results suggest that somatostatin-mediated proliferative effect on meningioma cells is not mediated by the subtype 2 of the somatostatin receptor.


Assuntos
Acromegalia/complicações , Neoplasias Meníngeas/etiologia , Meningioma/etiologia , Octreotida/efeitos adversos , Receptores de Somatostatina/efeitos dos fármacos , Acromegalia/tratamento farmacológico , Divisão Celular/efeitos dos fármacos , Fator de Crescimento Epidérmico/farmacologia , Feminino , Humanos , Imageamento por Ressonância Magnética , Neoplasias Meníngeas/patologia , Meningioma/patologia , Pessoa de Meia-Idade , Octreotida/uso terapêutico , Somatostatina/efeitos adversos , Somatostatina/análogos & derivados , Somatostatina/uso terapêutico , Células Tumorais Cultivadas
16.
Circ Res ; 89(12): 1111-21, 2001 Dec 07.
Artigo em Inglês | MEDLINE | ID: mdl-11739275

RESUMO

The adventitial layer surrounding the blood vessels has long been exclusively considered a supporting tissue the main function of which is to provide adequate nourishment to the muscle layers of tunica media. Although functionally interconnected, the adventitial and medial layers are structurally interfaced at the external elastic lamina level, clearly distinguishable at the maturational phase of vascular morphogenesis. Over the last few years the "passive" role that the adventitia seemed to play in experimental and spontaneous vascular pathologies involving proliferation, migration, differentiation, and apoptosis of vascular smooth muscle cells (VSMCs) has been questioned. It has been demonstrated that fibroblasts from the adventitia display an important partnership with the resident medial VSMCs in terms of phenotypic conversion, proliferation, apoptotic, and migratory properties the result of which is neointima formation and vascular remodeling. This article is an attempt at reviewing the major themes and more recent findings dealing with the phenotypic conversion process that leads adventitial "passive" (static) fibroblasts to become "activated" (mobile) myofibroblasts. This event shows some facets in common with vascular morphogenesis, ie, the process of recruitment, incorporation, and phenotypic conversion of cells surrounding the primitive endothelial tube in the definitive vessel wall. We hypothesize that during the response to vascular injuries in the adult, "activation" of adventitial fibroblasts is, at least in part, reminiscent of a developmental program that also invests, although with distinct spatiotemporal features, medial VSMCs.


Assuntos
Arteriopatias Oclusivas/patologia , Artérias/patologia , Fibroblastos/patologia , Músculo Liso Vascular/patologia , Túnica Íntima/patologia , Animais , Antígenos de Diferenciação/metabolismo , Arteriopatias Oclusivas/metabolismo , Artérias/embriologia , Artérias/metabolismo , Artérias/cirurgia , Diferenciação Celular , Divisão Celular , Movimento Celular , Progressão da Doença , Fibroblastos/metabolismo , Humanos , Morfogênese , Músculo Liso Vascular/embriologia , Músculo Liso Vascular/metabolismo , Veias/transplante
17.
Clin Chim Acta ; 312(1-2): 135-42, 2001 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-11580919

RESUMO

In this study we assessed whether the serum levels of the N-terminal peptide of type III collagen (PIIIP), an index of type III collagen synthesis, are influenced by colorectal cancer stage, and whether "in vitro" fibroblast growth and PIIIP production could be altered by tumor tissues obtained from metastatic and nonmetastatic colorectal cancer. 208 colorectal cancer patients (115 colon and 93 rectum) were studied; 54 were stage I, 62 stage II, 37 stage III and 55 stage IV. PIIIP serum levels were significantly higher in stage IV as compared to all other patient groups. The 5-year survival of stage I, stage II, stage III and stage IV patients were 87%, 88%, 32% and 20%, respectively. In the subgroup of stage I and stage II patients considered together, PIIIP (> 0.5 U/ml), but not CEA (> 5 microg/l) serum levels, were predictive for survival. Fibroblast growth was significantly inhibited, while PIIIP production was significantly enhanced, when these cells were conditioned with colorectal cancer homogenates obtained from patients with distant metastases, than from those without distant metastases. In conclusion, colorectal tumors, when metastatic, stimulate fibroblasts' PIIIP synthesis and the serum levels of this peptide might predict patients' outcome after radical surgery.


Assuntos
Colágeno Tipo III/sangue , Neoplasias Colorretais/metabolismo , Neoplasias Colorretais/patologia , Fibroblastos/metabolismo , Antígeno Carcinoembrionário/sangue , Divisão Celular , Células Cultivadas , Neoplasias Colorretais/mortalidade , Feminino , Fibroblastos/patologia , Humanos , Neoplasias Hepáticas/metabolismo , Neoplasias Hepáticas/patologia , Neoplasias Hepáticas/secundário , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Fragmentos de Peptídeos/sangue , Valor Preditivo dos Testes , Pró-Colágeno/sangue , Taxa de Sobrevida
18.
Am J Hypertens ; 13(12): 1256-62, 2000 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-11130768

RESUMO

The aim of the study was to investigate whether hypertension and physical training induce parallel changes in the arterial wall. Ninety-seven never-treated stage 1 hypertensive patients (HT) (systolic blood pressure 140 to 159 mm Hg or diastolic blood pressure 90 to 99 mm Hg) aged 18 to 45 years taking part in the Hypertension and Ambulatory Recording Venetia Study and 27 normotensive volunteers (NT) aged 30 +/- 9 years were studied. Data on physical or sports activity were collected and scored, and target organ involvement was investigated by assessing microalbuminuria, echocardiography, and carotid ultrasound study. The carotid arteries were examined according to the Atherosclerosis Risk in Communities protocol. Mean (m-IMT) and maximal (M-IMT) carotid intima-media thickness were measured at end-diastole in the far wall common carotid artery, in the bulb and internal carotid artery, in the lateral and posterior projection, averaging the left and right sides. A comparable level of physical activity was present in HT patients and NT subjects. Twenty-four-hour blood pressure and blood lipid levels, as well as target organ damage, were similar in physically active and sedentary HT. The m-IMT of the common carotid was greater in sedentary HT than in sedentary NT, as well as in active than in sedentary NT. The m-IMT of the internal carotid artery was also greater in active HT than in active NT, as well as in active than in sedentary HT. In logistic regression, comparing the first and fourth quartile of m-IMT, scored physical activity was a predictor of m-IMT in the internal carotid artery. No statistical interaction was found between physical activity and hypertension, indicating that these two items have a cumulative effect and act independently of each other. Sedentary HT had significantly greater levels of M-IMT than sedentary NT in all sites but the bulbs; in the internal and common carotid arteries, HT exercisers had significantly greater M-IMT than NT exercisers. Therefore, physical activity appears to be an early independent predictor of carotid wall thickness. This factor should be taken into consideration in population-based studies aimed at investigating supraortic vessels as it can act as a confounder.


Assuntos
Pressão Sanguínea , Artérias Carótidas/diagnóstico por imagem , Exercício Físico , Hipertensão/diagnóstico por imagem , Hipertensão/fisiopatologia , Túnica Íntima/diagnóstico por imagem , Túnica Média/diagnóstico por imagem , Adulto , Monitorização Ambulatorial da Pressão Arterial , Feminino , Humanos , Lipídeos/sangue , Masculino , Valores de Referência , Ultrassonografia
19.
Ann Thorac Surg ; 70(5): 1594-600, 2000 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-11093493

RESUMO

BACKGROUND: Cell populations present in human semilunar valves have not been investigated thoroughly. The aim of this study was to characterize the cell phenotypes in pulmonary valve leaflets (PVL) in comparison with aortic (AVL) valve leaflets. METHODS: AVL and PVL were dissected from hearts (n = 4) harvested from transplanted patients. Leaflets were processed for immunocytochemistry analysis and Western blotting procedures using a panel of monoclonal antibodies specific for cytoskeletal/contractile antigens. RESULTS: The fibrosa and the ventricularis layers of AVL had a higher cellularity than PVL. In PVL and AVL most cells were reactive for vimentin and nonmuscle (NM) myosin, though vimentin-positive cells were more abundant in AVL than in PVL. Sparse cells positive to anti-smooth muscle (SM) alpha-actin, calponin, and anti-SM myosin antibodies were found only at the outer edge of fibrosa. In Western blotting, AVL and PVL extracts were shown to be equally reactive for vimentin, SM alpha-actin, and NM myosin, whereas both valves were negative for SM myosin and SM22. CONCLUSIONS: Three distinct cell phenotypes have been identified in both valves: fibroblasts, myofibroblasts, and fetal-type SM cells whose distribution is specifically related to the valve layers. Although PVL and AVL cell populations differ quantitatively, some minor qualitative differences exist for vimentin and NM myosin distribution. These data are essential for studies aimed at repopulating valve scaffolds by using tissue engineering technology.


Assuntos
Valva Aórtica/citologia , Valva Pulmonar/citologia , Actinas/análise , Western Blotting , Proteínas de Ligação ao Cálcio/análise , Contagem de Células , Eletroforese , Fibroblastos/citologia , Humanos , Imuno-Histoquímica , Proteínas dos Microfilamentos , Proteínas Musculares/análise , Músculo Liso/citologia , Miosinas/análise , Vimentina/análise , Calponinas
20.
Circulation ; 102(7): 771-8, 2000 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-10942746

RESUMO

BACKGROUND: The purpose of this study was to investigate whether some cellular and molecular features of tissue retrieved at carotid endarterectomy are associated with the extent of neointima formation at ultrasound follow-up. METHODS AND RESULTS: One hundred fifty patients were studied. Endarterectomy specimens were tested by immunocytochemistry with the use of (1) monoclonal antibodies that identify smooth muscle cells (SMCs) and fetal-type SMCs on the basis of smooth muscle and nonmuscle myosin content, (2) the anti-macrophage HAM 56, and (3) the anti-lymphocyte CD45RO. The maximum intima-media thickness (M-IMT) of the revascularized vessel was assessed by the use of B-mode ultrasonography 6 months after surgery. The M-IMT values were related positively to the number of SMCs (r=0.534, P<0.0005) and negatively to that of macrophages and lymphocytes (r=-0.428, P<0.0005, and -0.538, P=0.001, respectively). Patients were classified as class 1 (M-IMT 1.3 mm). An abundance of SMCs, mostly of fetal type, was found in the plaque of class 3 patients, whereas lesions from class 1 patients were rich in macrophages and lymphocytes. In the multivariate analysis, factors related to M-IMT were the number of SMCs and the percentage of fetal-type SMCs present in the plaque. CONCLUSIONS: Although the classic risk factors did not play a role, an abundance of SMCs and a scarcity of macrophages characterized the primary lesion of patients in whom neointima developed after surgery. In patients in whom neointima did not develop, lesions were rich in macrophages and lymphocytes. This approach can be useful in defining patients at risk of restenosis.


Assuntos
Artérias Carótidas/patologia , Artérias Carótidas/cirurgia , Doenças das Artérias Carótidas/patologia , Doenças das Artérias Carótidas/cirurgia , Endarterectomia , Túnica Íntima/patologia , Idoso , Artérias Carótidas/diagnóstico por imagem , Doenças das Artérias Carótidas/diagnóstico por imagem , Feminino , Seguimentos , Humanos , Linfócitos/patologia , Macrófagos/patologia , Masculino , Pessoa de Meia-Idade , Músculo Liso Vascular/patologia , Período Pós-Operatório , Recidiva , Fatores de Risco , Túnica Íntima/diagnóstico por imagem , Túnica Íntima/crescimento & desenvolvimento , Túnica Média/diagnóstico por imagem , Ultrassonografia
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