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911.
Neurological Sciences - To study for the first time the incidence of adult-onset CNS tumors in Southern Sardinia, Italy. Clinical records of patients > 18 years old who...  相似文献   
912.
Angiogenesis as a novel component of inflammatory bowel disease pathogenesis   总被引:14,自引:0,他引:14  
BACKGROUND & AIMS: Angiogenesis is a critical component of neoplastic and chronic inflammatory disorders, but whether angiogenesis also occurs in inflammatory bowel disease (IBD) has yet to be established. We assessed mucosal vascularization, expression of endothelial alphaVbeta3 integrin, angiogenic factors, and their bioactivity in Crohn's disease (CD) and ulcerative colitis (UC) mucosa. METHODS: Mucosal endothelium was immunostained for CD31 and factor VIII and quantified by digital morphometry. alphaVbeta3 expression was studied in vivo by confocal microscopy and in vitro by flow cytometric analysis of human intestinal microvascular endothelial cells (HIMECs). Vascular endothelial growth factor (VEGF), interleukin (IL)-8, and bFGF levels were measured in mucosal extracts and cells and angiogenic bioactivity shown by induction of HIMEC migration and the corneal and chorioallantoic membrane angiogenesis assays. RESULTS: Microvessel density was increased in IBD mucosa. Endothelial alphaVbeta3 was strongly expressed in IBD but only sporadically in normal mucosa and was up-regulated in HIMECs by VEGF, tumor necrosis factor alpha, and bFGF. IBD mucosal extracts induced a significantly higher degree of HIMEC migration than control mucosa, and this response was mostly dependent on IL-8 and less on basic fibroblast growth factor or vascular endothelial growth factor. Compared with normal mucosa, IBD mucosal extracts induced a potent angiogenic response in both the corneal and chorioallantoic membrane assays. CONCLUSIONS: These results provide morphological, phenotypic and functional evidence of potent angiogenic activity in both CD and UC mucosa, indicating that the local microvasculature undergoes an intense process of inflammation-dependent angiogenesis. Thus, angiogenesis appears to be an integral component of IBD pathogenesis, providing the practical and conceptual framework for anti-angiogenic therapies in IBD.  相似文献   
913.
In recent years, great emphasis has been placed on the role of arterial stiffness in the development of cardiovascular diseases. Indeed, the assessment of arterial stiffness is increasingly used in the clinical assessment of patients. Although several papers have previously addressed the methodological issues concerning the various indices of arterial stiffness currently available, and their clinical applications, clinicians and researchers still report difficulties in selecting the most appropriate methodology for their specific use. This paper summarizes the proceedings of several meetings of the European Network for Non-invasive Investigation of Large Arteries and is aimed at providing an updated and practical overview of the most relevant methodological aspects and clinical applications in this area.  相似文献   
914.
Summary β-thromboglobulin (BTG) and fibrinopeptide A (FpA) were studied in 68 non-insulin dependent diabetic patients (NIDD) aged 32–81 with a mean duration of diabetes of 9±0.8 SEM years and 44 healthy controls, comparable for age and sex. Diabetic patients were subdivided into subsets according to the presence of microvascular disease, macrovascular disease or the absence of these lesions. Patients with microangiopathy (micro- and/or macrovascular disease) had higher HbA (p<0.01), higher blood pressure (p<0.05) than both healthy controls and uncomplicated diabetics. Plasma BTG was higher in diabetic patients than in healthy controls (p<0.02), and was higher in complicated than in non-complicated diabetic subjects. Fpa was higher in complicated than in non-complicated diabetes (p<0.05). No differences were observed between the two subsets of complicated patients. In conclusion, we have shown that increased plasma- and platelet-BTG levels are present in non-insulin dependent diabetic subjects, with normal renal function and that plasma BTG is higher in patients with than in those without vascular disease. Fibrinopeptide A, a sensitive marker ofin vivo fibrin formation, was significantly increased in NIDD with vascular complications. This study was supported by the Juvenile Diabetes Foundation Grant N. 184066 and by the National Research Council of Italy,Progetto Finalizzato di Medicina Preventiva e Riabilitativa, Sottoprogetto 4.  相似文献   
915.
Background and aimsAdvances in colonoscopy, such as the Pentax i-Scan electronic technique, have the potential to improve the early detection of colorectal cancer. The aim of this multicentre study was to assess the interobserver agreement in the visualization of the surface and margins of colorectal polyps and in distinguishing neoplastic from non-neoplastic polyps.Patients and methodsEight expert endoscopists examined 400 mixed previously recorded images of polyps taken with different Pentax i-Scan settings in order to give an evaluation of the surface of the polyp and regular colonic mucosa, the pit-pattern and the nature of the lesion.ResultsA total of 400 mixed images of polyps with a diameter >5 mm and <10 mm were stored for analysis. Overall, there was a Kf agreement of 0.370 (p < 0.001) and 0.306 (p < 0.001) regarding pit-pattern and margins, respectively. The Kf agreement for the difference between neoplastic and non-neoplastic lesions was of 0.446 (p < 0.001).ConclusionsWe observed good interobserver agreement in the evaluation of neoplastic and non-neoplastic lesions and poor agreement in the evaluation of pit-pattern and margins. Adequate training is required in order to interpret images acquired with the i-Scan technique.  相似文献   
916.
Cutaneous vasculitis may be associated with malignancies, and may behave as a paraneoplastic syndrome. This association has been reported in a variable proportion of patients depending on population selection. We conducted the current study to assess the frequency, clinical features, treatment, and outcome of paraneoplastic vasculitis in a large unselected series of 766 patients with cutaneous vasculitis diagnosed at a single university hospital.Sixteen patients (10 men and 6 women; mean age ± standard deviation, 67.94 ± 14.20 yr; range, 40–85 yr) presenting with cutaneous vasculitis were ultimately diagnosed as having an underlying malignancy. They constituted 3.80% of the 421 adult patients. There were 9 hematologic and 7 solid underlying malignancies. Skin lesions were the initial clinical presentation in all of them, and the median interval from the onset of cutaneous vasculitis to the diagnosis of the malignancy was 17 days (range, 8–50 d). The most frequent skin lesions were palpable purpura (15 patients). Other clinical manifestations included constitutional syndrome (10 patients) and arthralgia and/or arthritis (4 cases). Hematologic cytopenias (11 cases) as well as immature peripheral blood cells (6 cases) were frequently observed in the full blood cell count, especially in those with vasculitis associated with hematologic malignancies.Specific treatment for vasculitis was prescribed in 10 patients; nonsteroidal antiinflammatory drugs (4 patients), corticosteroids (3 patients), chloroquine (1 patient), antihistamines (1 patient), and cyclophosphamide (1 patient). Ten patients died due to the malignancy and 6 patients recovered following malignancy therapy. Patients with paraneoplastic vasculitis were older, more frequently had constitutional syndrome, and less frequently had organ damage due to the vasculitis than the remaining patients with cutaneous vasculitis.In summary, cutaneous paraneoplastic vasculitis is an entity not uncommonly encountered by clinicians. The most common underlying malignancy is generally hematologic. In these cases the presence of cytopenias and immature cells may be red flags for the diagnosis of cancer. In patients with paraneoplastic cutaneous vasculitis, the prognosis depends on the underlying neoplasia.  相似文献   
917.

Aim

The aim of the study was to evaluate the association between high plasma ADMA levels, a biomarker of endothelial dysfunction, with the progression of albuminuria and chronic kidney disease (CKD) in hypertensive patients, with and without type 2 diabetes mellitus.

Methods

We successfully contacted 213 of 644 patients who had been evaluated between 2004 and 2005 and for whom basal data were available. After the exclusion of 51 patients, 162 hypertensive patients who were free from albuminuria were stratified into the following 4 groups according to the presence of diabetes and plasma ADMA percentiles: general hypertensive patients with high levels of plasma ADMA (>P4 or ADMA?>?0.61?μmol/L), general hypertensive patients with low levels of plasma ADMA (≤P4), diabetic hypertensive patients with high levels of plasma ADMA (>P4), and diabetic hypertensive patients with low levels of plasma ADMA (≤P4).

Results

The patients were prospectively evaluated over 5.8?years. High ADMA levels were associated with the progression of albuminuria in hypertensive patients, with and without type 2 diabetes. Major increases in the ADMA value during follow-up were associated with the progression of CKD, and direct correlations between ADMA changes and GFR changes were observed in the whole group and in the subgroup of diabetic patients.

Conclusions

We suggest that high plasma ADMA levels might be a biomarker of renal disease progression and might even be an early predictor of albuminuria and its progression to the late stages of renal disease in hypertensive and diabetic hypertensive patients.  相似文献   
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