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51.
Cancer and stromal cells, which include (cancer‐associated) fibroblasts, adipocytes, and immune cells, constitute a mixed cellular ecosystem that dynamically influences the behavior of each component, creating conditions that ultimately favor the emergence of malignant clones. Ovarian cancer cells release cytokines that recruit and activate stromal fibroblasts and immune cells, so perpetuating a state of inflammation in the stroma that hampers the immune response and facilitates cancer survival and propagation. Further, the stroma vasculature impacts the metabolism of the cells by providing or limiting the availability of oxygen and nutrients. Autophagy, a lysosomal catabolic process with homeostatic and prosurvival functions, influences the behavior of cancer cells, affecting a variety of processes such as the survival in metabolic harsh conditions, the invasive growth, the development of immune and chemo resistance, the maintenance of stem‐like properties, and dormancy. Further, autophagy is involved in the secretion and the signaling of promigratory cytokines. Cancer‐associated fibroblasts can influence the actual level of autophagy in ovarian cancer cells through the secretion of pro‐inflammatory cytokines and the release of autophagy‐derived metabolites and substrates. Interrupting the metabolic cross‐talk between cancer cells and cancer‐associated fibroblasts could be an effective therapeutic strategy to arrest the progression and prevent the relapse of ovarian cancer. 相似文献
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A randomized trial of ultrasound-guided anterior subcostal liver biopsy versus the conventional Menghini technique 总被引:2,自引:0,他引:2
Enrico Papini Claudio M. Pacella Zaccaria Rossi Giancarlo Bizzarri Rossella Fabbrini Francesco Nardi Roberto Picardi 《Journal of hepatology》1991,13(3):291-297
An ultrasound-guided double pass biopsy technique using a large bore cutting needle via an anterior subcostal route (USAB) is described. The diagnostic adequacy of this biopsy procedure was evaluated in comparison with the traditional Menghini technique in 200 cases of suspected chronic liver disease randomly assigned to the two different procedures. Retrieval rate was better in the USAB group. The sample length was less than 15 mm in four cases in the USAB group and in 19 cases in the Menghini group. In three cases in the USAB group the second pass modified the diagnosis of the first specimen from chronic active hepatitis to active cirrhosis. In order to evaluate the safety and discomfort of the two procedures 340 patients assigned to the different techniques had liver ultrasound scans 6 and 24 h following percutaneous biopsy. USAB was associated with a reduced frequency of complications (one out of 170 patients vs. seven out of 170 patients who had the intercostal Menghini procedure). In our study, USAB seems to offer better sampling and size of individual samples, together with reduced frequency of major and minor complications. 相似文献
54.
Dioguardi N Franceschini B Russo C Grizzi F 《World journal of gastroenterology : WJG》2005,11(44):6995-7000
AIM: To introduce a computer-aided morphometric method for quantifying the necro-inflammatory phase in liver biopsy specimens using fractal geometry and Delaunay's triangulation. METHODS: Two-micrometer thick biopsy sections taken from 78 chronic hepatitis C virus-infected patients were immunohistochemically treated to identify the inflammatory cells. An automatic computer-aided image analysis system was used to define the inflammatory cell network defined on the basis of Delaunay's triangulation, and the inflammatory cells were geometrically classified as forming a cluster (an aggregation of a minimum of three cells) or as being irregularly distributed within the tissue. The phase of inflammatory activity was estimated using Hurst's exponent. RESULTS: The proposed automatic method was rapid and objective. It could not only provide rigorous results expressed by scalar numbers, but also allow the state of the whole organ to be represented by Hurst's exponent with an error of no more than 12%. CONCLUSION: The availability of rigorous metrical measures and the reasonable representativeness of the status of the organ as a whole raise the question as to whether the indication for hepatic biopsy should be revised by establishing clear rules concerning the contraindications suggested by its invasiveness and subjective interpretation. 相似文献
55.
Cammarota G Martino A Pirozzi GA Cianci R Cremonini F Zuccalà G Cuoco L Ojetti V Montalto M Vecchio FM Gasbarrini A Gasbarrini G 《Gastrointestinal endoscopy》2004,60(5):732-738
BACKGROUND: New generation videoendoscopes potentially may visualize duodenal villi. This study compared endoscopic findings with this type of instrument to the histopathologic evaluation of duodenal villi. METHODS: A total of 191 patients underwent upper endoscopy for the purpose of obtaining duodenal biopsy specimens. The findings were assessed independently by 3 experienced observers by using a commercially available, high-resolution, high-magnifying (x2) videoendoscope. The duodenal villous profile was determined by endoscopic magnification and by endoscopic magnification after filling the duodenum with water. With both endoscopic magnification and endoscopic magnification after filling the duodenum with water, villous patterns were scored as the following: definitely present, partially present, or definitely absent. Villous patterns also were histopathologically scored as the following: normal, partial villous pattern, or total villous atrophy. RESULTS: Interobserver variability was excellent (kappa = 0.93). The concordance between either endoscopic magnification or endoscopic magnification after filling the duodenum with water and histology was 100% for presence/absence of villi. The sensitivity, the specificity, and the positive and negative predictive values of endoscopic magnification for detection of any villous abnormality were 95%, 99%, 95%, and 99%, respectively; the respective values of endoscopic magnification after filling the duodenum with water were 95%, 98%, 92%, and 99%. CONCLUSIONS: High-resolution magnifying upper endoscopy can reliably predict the presence or the absence of duodenal villi. 相似文献
56.
QT-interval prolongation in right precordial leads: an additional electrocardiographic hallmark of Brugada syndrome 总被引:2,自引:0,他引:2
Pitzalis MV Anaclerio M Iacoviello M Forleo C Guida P Troccoli R Massari F Mastropasqua F Sorrentino S Manghisi A Rizzon P 《Journal of the American College of Cardiology》2003,42(9):1632-1637
OBJECTIVES: The aim of this study was to evaluate whether the occurrence of the Brugada Syndrome typical electrocardiogram (ECG) pattern (i.e., right bundle branch block, coved-type ST-segment elevation, and T-wave inversion in the right precordial leads) is characterized by a concomitant lengthening of QT intervals in the right precordial leads. BACKGROUND: It has been suggested that the typical ECG pattern of Brugada syndrome is due to a decreased net inward current during phase 1 of the action potential, which also leads to its prolongation in the right epicardium. METHODS: Thirty-two subjects (19 males) age 37 +/- 15 years with a suspicious baseline ECG, or who were relatives of Brugada syndrome patients, underwent 12-lead ECG before and after the administration of flecainide. RESULTS: The flecainide test was negative in 14 and positive in 18 subjects. After flecainide administration, the positive ECGs were characterized by a greater QT interval corrected for heart rate (QTc) prolongation in the right precordial leads than that in the negative ECGs (78.2 +/- 35.5 ms vs. 22.0 +/- 28.4 ms in V(1) and 107.1 +/- 43.8 ms vs. 26.7 +/- 30.1 ms in V(2); p < 0.01), whereas there was no difference in the QTc prolongation in the left precordial leads (55.2 +/- 25.3 ms vs. 35.1 +/- 28.1 ms in V(5) and 53.1 +/- 32.8 ms vs. 27.3 +/- 22.4 ms in V(6); p = NS). CONCLUSIONS: In accordance with the electrophysiological background, the typical ECG pattern of Brugada syndrome is also characterized by a considerable prolongation of the QT interval in right precordial leads. 相似文献
57.
Priori R Medda E Conti F Cassara EA Danieli MG Gerli R Giacomelli R Franceschini F Manfredi A Pietrogrande M Stazi MA Valesini G 《Lupus》2003,12(10):735-740
The objective of this multicentric case-control study was to investigate if a history of autoimmune disease (AD) in first-degree relatives (FDR) is a risk factor for systemic lupus erythematosus (SLE) and to evaluate the risk of AD among FDR of SLE patients. Cases were Italian SLE patients consecutively enrolled. Controls were orthopaedic inpatients without any autoimmune diseases. The strength of the association between family history of AD and SLE was measured as an odds ratio (OR) calculated from the coefficient of an unconditional regression model. To calculate the risk of AD among FDR of SLE patients, the extended generalized estimating equation technique was used. In total, 154 SLE cases and 140 controls were enrolled. A family history of AD was reported by 22.7% of SLE patients and by 5.7% of the controls. The risk of SLE increased with the number of FDR with AD (one FDR affected, OR = 4.1; two or more, OR = 11.3). The probability of having AD was higher among FDR of SLE cases in comparison to FDR of controls (RR = 4.6; 95%CI 1.9-11.1). A female SLE patient conferred an increased risk of AD to her FDR; this risk is doubled in females (OR 10.3; 95% CI 3.1-34.4). 相似文献
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59.
Angelo Picardi Rossella Miglio Lorenzo Tarsitani Francesca Battisti Maurizio Baldassari Alfredo Copertaro Eugenio Mocchegiani Isabella Cascavilla Massimo Biondi 《Biological psychology》2013
Previous cross-sectional studies suggested an association between attachment-related avoidance and altered immune function. We aimed at testing this hypothesis with longitudinal data. A random sample of 65 female nurses provided a blood sample and completed measures of perceived stress, social support, alexithymia, and attachment style. Immune assays included lymphocyte proliferative response (LPR) to Phytohemagglutinin and NK cell cytotoxicity (NKCC). State measures (perceived stress and support) and immune measures were collected again after 4, 8, and 12 months. Linear mixed effects models were used to examine the relationship between attachment and immunity. While low to moderate levels of attachment-related avoidance were not associated with NKCC, there was a significant negative association (beta −.35; p = .005) between high levels of avoidance and NKCC. No association was observed between NKCC and attachment-related anxiety, and between LPR and both attachment dimensions. While our findings should be interpreted with caution due to study limitations such as the relatively small sample size and the inclusion of only female participants, they corroborate the notion that attachment is linked to physiology and health. 相似文献
60.
Innocenti Francesca Gori Anna Maria Giusti Betti Tozzi Camilla Donnini Chiara Meo Federico Giacomelli Irene Ralli Maria Luisa Sereni Alice Sticchi Elena Tassinari Irene Marcucci Rossella Pini Riccardo 《Clinical and experimental medicine》2021,21(1):101-107
Clinical and Experimental Medicine - The aim of the study is to evaluate the prognostic value of early PCSK9 levels in non-intubated septic patients admitted to the emergency department. This... 相似文献