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Vasileios Mourmouras Gabriele Cevenini Elena Cosci Maria C. Epistolato Maurizio Biagioli Letizia Barbagli Pietro Luzi Susanna Mannucci and Clelia Miracco 《Journal of cutaneous pathology》2009,36(6):637-646
Background: Nucleolin is a major nucleolar argyrophilic protein involved in carcinogenesis. There are only few studies on its tissue expression in human cancer and none in melanoma. We aimed at exploring this protein and its prognostic impact in cutaneous melanocytic lesions.
Methods: We studied 193 cases including benign, dysplastic and malignant melanocytic lesions. Nuclear positivity was evaluated by immunohistochemistry and quantified by automated image analysis.
Results: Most dysplastic and malignant lesions showed high percentages of cells with abnormal patterns of nuclear positivity (Abn+N) consisting in multiple, irregular, positive dots (ID+) and a coarse, irregularly positive nucleoplasm (CNpl+) or both (ID+CNpl+). The patterns CNpl+ and/or ID+CNpl+ were never observed in benign lesions, in which ID+ were also virtually absent. Abn+N% was significantly lower in dysplastic nevi than in primary melanomas and metastases and in primary melanomas than in metastases (p < 0.05). Furthermore, Abn+N was the second powerful prognostic discriminator, after melanoma thickness, and a significantly lower survival was observed in vertical growth phase melanoma patients showing Abn+N in more than 50% of melanoma cells.
Conclusion: An altered nuclear nucleolin expression seems to accompany melanoma progression. Further investigation on nucleolin functionality and subcellular trafficking could add information on its altered role in melanoma. 相似文献
Methods: We studied 193 cases including benign, dysplastic and malignant melanocytic lesions. Nuclear positivity was evaluated by immunohistochemistry and quantified by automated image analysis.
Results: Most dysplastic and malignant lesions showed high percentages of cells with abnormal patterns of nuclear positivity (Abn+N) consisting in multiple, irregular, positive dots (ID+) and a coarse, irregularly positive nucleoplasm (CNpl+) or both (ID+CNpl+). The patterns CNpl+ and/or ID+CNpl+ were never observed in benign lesions, in which ID+ were also virtually absent. Abn+N% was significantly lower in dysplastic nevi than in primary melanomas and metastases and in primary melanomas than in metastases (p < 0.05). Furthermore, Abn+N was the second powerful prognostic discriminator, after melanoma thickness, and a significantly lower survival was observed in vertical growth phase melanoma patients showing Abn+N in more than 50% of melanoma cells.
Conclusion: An altered nuclear nucleolin expression seems to accompany melanoma progression. Further investigation on nucleolin functionality and subcellular trafficking could add information on its altered role in melanoma. 相似文献
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Intrasplenic hepatocellular transplantation corrects hepatic encephalopathy in portacaval-shunted rats. 总被引:7,自引:0,他引:7
J Ribeiro B Nordlinger F Ballet L Cynober C Coudray-Lucas M Baudrimont C Legendre R Delelo Y Panis 《Hepatology (Baltimore, Md.)》1992,15(1):12-18
The aim of this work was to evaluate the effect of intrasplenic hepatocellular transplantation on hepatic encephalopathy in an experimental model of chronic liver failure induced by end-to-side portacaval shunt in the rat. Inbred male Wistar Furth rats were divided into three groups: rats subjected to portacaval shunt (n = 10), rats subjected to portacaval shunt and intrasplenic hepatocellular transplantation of 10(7) hepatocytes isolated from livers of syngeneic rats (n = 10) and sham-operated rats (n = 10). Behavior tests were performed in a blind fashion at 3 wk, at 2 mo and at 3 mo after surgery. Spontaneous activity and nose-poke exploration by individual rats were studied in automated open field boxes equipped with infrared cells. Each cell beam interruption was automatically recorded on a microcomputer and transformed into a score index (counts/hour). Plasma levels of amino acids, ammonia and total biliary acids were measured. Portacaval shunt rats showed reduced spontaneous activity and nose-poke exploration scores. Intrasplenic hepatocellular transplantation significantly increased spontaneous activity after 2 mo and improved nose-poke exploration after 3 wk. At 3 mo, spontaneous activity and nose-poke exploration in portacaval shunt/intrasplenic hepatocellular transplantation rats were not significantly different from those of sham rats. Increases in plasma ammonia levels after portacaval shunt were not corrected. Amino acid imbalance and bile acid concentration in plasma were partially corrected by intrasplenic hepatocellular transplantation. These data show that intrasplenic hepatocellular transplantation can correct the neurological symptoms of hepatic encephalopathy in an experimental model of chronic liver failure and suggest that intrasplenic hepatocellular transplantation might be of therapeutic interest in chronic liver failure. 相似文献
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Applying spatial distribution analysis techniques to classification of 3D medical images 总被引:3,自引:0,他引:3
Pokrajac D Megalooikonomou V Lazarevic A Kontos D Obradovic Z 《Artificial intelligence in medicine》2005,33(3):261-280
OBJECTIVE: The objective of this paper is to classify 3D medical images by analyzing spatial distributions to model and characterize the arrangement of the regions of interest (ROIs) in 3D space. METHODS AND MATERIAL: Two methods are proposed for facilitating such classification. The first method uses measures of similarity, such as the Mahalanobis distance and the Kullback-Leibler (KL) divergence, to compute the difference between spatial probability distributions of ROIs in an image of a new subject and each of the considered classes represented by historical data (e.g., normal versus disease class). A new subject is predicted to belong to the class corresponding to the most similar dataset. The second method employs the maximum likelihood (ML) principle to predict the class that most likely produced the dataset of the new subject. RESULTS: The proposed methods have been experimentally evaluated on three datasets: synthetic data (mixtures of Gaussian distributions), realistic lesion-deficit data (generated by a simulator conforming to a clinical study), and functional MRI activation data obtained from a study designed to explore neuroanatomical correlates of semantic processing in Alzheimer's disease (AD). CONCLUSION: Performed experiments demonstrated that the approaches based on the KL divergence and the ML method provide superior accuracy compared to the Mahalanobis distance. The later technique could still be a method of choice when the distributions differ significantly, since it is faster and less complex. The obtained classification accuracy with errors smaller than 1% supports that useful diagnosis assistance could be achieved assuming sufficiently informative historic data and sufficient information on the new subject. 相似文献
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Petter Fagerberg Evangelia Charmandari Christos Diou Rachel Heimeier Youla Karavidopoulou Penio Kassari Evangelia Koukoula Irini Lekka Nicos Maglaveras Christos Maramis Ioannis Pagkalos Vasileios Papapanagiotou Katerina Riviou Ioannis Sarafis Athanasia Tragomalou Ioannis Ioakimidis 《Nutrients》2021,13(3)
Fast self-reported eating rate (SRER) has been associated with increased adiposity in children and adults. No studies have been conducted among high-school students, and SRER has not been validated vs. objective eating rate (OBER) in such populations. The objectives were to investigate (among high-school student populations) the association between OBER and BMI z-scores (BMIz), the validity of SRER vs. OBER, and potential differences in BMIz between SRER categories. Three studies were conducted. Study 1 included 116 Swedish students (mean ± SD age: 16.5 ± 0.8, 59% females) who were eating school lunch. Food intake and meal duration were objectively recorded, and OBER was calculated. Additionally, students provided SRER. Study 2 included students (n = 50, mean ± SD age: 16.7 ± 0.6, 58% females) from Study 1 who ate another objectively recorded school lunch. Study 3 included 1832 high-school students (mean ± SD age: 15.8 ± 0.9, 51% females) from Sweden (n = 748) and Greece (n = 1084) who provided SRER. In Study 1, students with BMIz ≥ 0 had faster OBER vs. students with BMIz < 0 (mean difference: +7.7 g/min or +27%, p = 0.012), while students with fast SRER had higher OBER vs. students with slow SRER (mean difference: +13.7 g/min or +56%, p = 0.001). However, there was “minimal” agreement between SRER and OBER categories (κ = 0.31, p < 0.001). In Study 2, OBER during lunch 1 had a “large” correlation with OBER during lunch 2 (r = 0.75, p < 0.001). In Study 3, fast SRER students had higher BMIz vs. slow SRER students (mean difference: 0.37, p < 0.001). Similar observations were found among both Swedish and Greek students. For the first time in high-school students, we confirm the association between fast eating and increased adiposity. Our validation analysis suggests that SRER could be used as a proxy for OBER in studies with large sample sizes on a group level. With smaller samples, OBER should be used instead. To assess eating rate on an individual level, OBER can be used while SRER should be avoided. 相似文献
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Anastasios Serbis Vasileios Giapros Eleni P Kotanidou Assimina Galli-Tsinopoulou Ekaterini Siomou 《World journal of diabetes》2021,12(4):344-365
During the last two decades, there have been several reports of an increasing incidence of type 2 diabetes mellitus (T2DM) in children and adolescents, especially among those belonging to minority ethnic groups. This trend, which parallels the increases in prevalence and degree of pediatric obesity, has caused great concern, even though T2DM remains a relatively rare disease in children. Youth T2DM differs not only from type 1 diabetes in children, from which it is sometimes difficult to differentiate, but also from T2DM in adults, since it appears to be an aggressive disease with rapidly progressive β-cell decline, high treatment failure rate, and accelerated development of complications. Despite the recent research, many aspects of youth T2DM still remain unknown, regarding both its pathophysiology and risk factor contribution, and its optimal management and prevention. Current management approaches include lifestyle changes, such as improved diet and increased physical activity, together with pharmacological interventions, including metformin, insulin, and the recently approved glucagon-like peptide-1 analog liraglutide. What is more important for everyone to realize though, from patients, families and physicians to schools, health services and policy-makers alike, is that T2DM is a largely preventable disease that will be addressed effectively only if its major contributor (i.e., pediatric obesity) is confronted and prevented at every possible stage of life, from conception until adulthood. Therefore, relevant comprehensive, coordinated, and innovative strategies are urgently needed. 相似文献
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Zoi Tsimtsiou Ioanna Tsiligianni Anastasia Papaioannou Dimitrios Gougourelas Konstantinos Kolokas Vasileios Gkizlis Emmanuil Chatzimanolis Philippe-Richard J. Domeyer 《Health & social care in the community》2021,29(3):818-828
Despite the unequivocal value of vaccination in reducing the global burden of infectious diseases, the anti-vaccination movement thrives. The vast majority of the existing validated tools explore attitudes regarding vaccination in children. The aim of our study was to develop and validate a scale assessing attitudes towards adult immunisation. This national cross-sectional study included adult healthcare users who visited 23 Greek Primary Healthcare Units. The development of the scale was the result of literature review, semi-structured interviews and pilot testing of its preliminary versions. The initial version contained 15 items measuring respondents’ attitudes on a 6-point Likert scale. The sample was randomly split into two halves. Exploratory factor analysis, performed in the first sample, was used for the creation of multi-item scales; confirmatory factor analysis was used in the second sample to assess goodness of fit. Moreover, concurrent validity, internal consistency reliability, test–retest reliability and ceiling and floor effects were explored. The total sample consisted of 1,571 individuals. Overall ‘Cronbach's alpha’ (0.821) indicated good internal consistency. The initial exploratory factor analysis resulted in a three-factor model. The subsequent confirmatory factor analysis indicated that an 11-item version of the scale provided the best fit of the model to the data (RMSEA = 0.050, SRMR = 0.053, TLI = 0.937, CFI = 0.955, AIC = 24,999.949). All subscales (‘value of adult vaccination’, ‘safety concerns’ and ‘perceived barriers’) demonstrated strong concurrent associations with participants’ attitudes and behaviour regarding vaccination (p < .001). No ceiling or floor effects were noted for any of the subscales (0.13%, 2.61% and 0.51%; 0.13%, 0.57% and 0.45% respectively). The 11-item ATAVAC scale proved to be a reliable and valid tool, suitable for assessing attitudes towards adult vaccination. 相似文献
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