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91.
Castaños-Vélez E Heiden T Lindvall C Capello D Sandlund A Imreh S Blennow E Andersson LC Gaidano G Nordenskjöld M Biberfeld P 《AIDS research and human retroviruses》2002,18(5):383-390
Simian AIDS-related lymphomas (sARL) of cynomolgus monkeys infected with a simian immunodeficiency virus (SIVsm) were studied in relation to growth in severe combined immunodeficient (SCID) mice, karyotype abnormalities, and DNA sequence of the first noncoding region of the Bcl-6 gene. The tumors were diffuse large B cell lymphomas and expressed a simian homolog to Epstein-Barr virus (HVMF-1) in 12 of 13 primary tumors and corresponding cell lines. A tested cell line was tumorigenic in SCID mice. Tumors in the SCID mice showed cell growth features similar to those in the original lymphoma, suggesting that no subpopulation with growth advantage was selected for in the mice. Spectral karyotype analysis of sARL cell lines showed normal cytogenetic features except for a trisomy of monkey chromosome 2 (corresponding to human chromosomes 7 and 21) in two of five sARL lines, which was not recovered in SCID tumors established from the same cell line. Sequence analysis of a Bcl-6 gene fragment showed sequence variations indicative of population polymorphism(s) in 10 of 13 sARLs, and no evidence of Bcl-6 mutations. Thus Bcl-6 mutations in the first noncoding region are irrelevant for sARL development in cynomolgus monkeys and for tumorigenicity of sARL cell lines. We also demonstrate that no cytogenetic alterations are needed for the development of highly aggressive lymphomas in the SIV-immunosuppressed host. 相似文献
92.
Molecular pathogenesis of HIV-associated lymphomas. 总被引:1,自引:0,他引:1
P Ballerini G Gaidano J Gong V Tassi G Saglio D M Knowles R Dalla-Favera 《AIDS research and human retroviruses》1992,8(5):731-735
The data presented here indicate that the pathogenesis of AIDS-NHL is variably associated with multiple genetic alterations including monoclonal EBV infection, oncogene activation (c-myc, N-, Ki-ras) and tumor suppressor gene (p53) inactivation. Up to three (3 cases) or four (1 case) different lesions have been observed in the same tumor. The distribution of these lesions among the various histotypes is heterogeneous, although some preferential associations have been found either between lesion and histotype or between lesions. The most notable case involves p53 mutations/loss that is exclusively associated with the SNCC lymphoma subtype. Since alterations of the c-myc gene occur at very high frequency in this same histotype it is possible that both lesions may be required for the pathogenesis of the BL phenotype. The consistent negativity of p53 lesions in other NHLs associated or non associated with HIV infection (18) reinforces this hypothesis. Finally, we note that the frequency of p53 mutations is significantly higher in AIDS-BL than in non HIV-related BL (18), although the significancy of this difference remains to be assessed. This study confirms the relatively low frequency of EBV infection in systemic AIDS-NHL in general, but reinforces the notion that EBV may be required for the pathogenesis of AIDS-LC-IBP, as recently suggested by the high frequency of EBV positivity in primary CNS AIDS-NHL which are mostly represented by LC-IBP (2). Conversely, the low frequency of EBV sequences in the AIDS-SNCC lymphomas appears similar to that observed in sBL. Only in a small minority of cases were ras oncogene mutations found, mostly associated with the BL type.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
93.
OBJECTIVE To investigate the basal levels of gonadotrophins and sex steroids, with special reference to the effects of obesity and body fat distribution, In premenopausal women, both those with polycystic ovary syndrome (PCOS) and those with normal ovaries and regular menstrual cycles. DESIGN Cross-sectional study. The separate effects of obesity (and body fat distribution and fasting Insulin levels) and PCOS on endocrine variables were evaluated by means of analysis of covariance. PATIENTS Sixty-seven women with anovulatory menstrual cycles and polycystic ovaries according to ultrasonography and 59 women with normal ovaries and regular cycles, both groups covering a wide range of body mass index (BMI, PCOS, 17·6-37·4, mean 25·7 kg/m2; controls, 18·8-40·9, mean 25·1 kg/m2). MEASUREMENTS Serum levels of gonadotrophins, sex steroid hormones, prolactin and GH obtained in the early follicular phase in the controls, fasting insulin levels, anthropometric measures (BMI, skinfolds, waist hip ratio). RESULTS Mean serum concentrations of LH, andro-stenedione, testosterone, the free androgen index (FAI; all P < 0·0001) and DHEAS (P < 0·01) were higher, and serum FSH (P < 0·01) and serum SHBG levels lower (P < 0·0001), in the PCOS group than in the controls. Women with PCOS had a more pronounced upper body fat distribution and higher fasting insulin levels than the controls. Independent of PCOS, BMI was positlvely associated with serum levels of FSH (P < 0·001) and negatively with levels of LH (P < 0·05), LH/FSH ratio (P < 0·0001), SHBG (P < 0·0001) and androstenedione (P < 0·01), whereas for levels of testosterone, FAI and DHEAS the impact of obesity differed significantly between the groups. Thus, in the PCOS group, testosterone levels (P < 0·05) and the FAI (P < 0·001) were positively associated with BMI, whereas they were constant throughout the entire range of BMI in the controls. DHEAS levels were positively associated with BMI in the PCOS group (P < 0·05) and negatively in the controls (P < 0·01). Measures of upper body fat were related to testosterone and FAI levels, independent of BMI. CONCLUSIONS Lower FSH levels were found in women with PCOS than during the early follicular phase of normally ovulating women, suggesting a role in anovulation in PCOS. Obesity itself exerted effects on endocrine variables, with the net result of a reduced LHIFSH ratio and lower serum levels of androstenedione and SHBG in both groups; obesity was associated with increased levels of DHEAS, testosterone and FAI exclusively in the women with PCOS. The results underline the endocrine impact of obesity and body fat distribution and the necessity of applying reference values of BMI matched subjects when establishing the endocrine profile of women with PCOS. 相似文献
94.
Pre-Menopausal Breast Fat Density Might Predict MACE During 10 Years of Follow-Up: The BRECARD Study
Celestino Sardu Gianluca Gatta Gorizio Pieretti Luigi Viola Cosimo Sacra Graziella Di Grezia Lanfranco Musto Salvatore Minelli Daniele La Forgia Mariangela Capodieci Alessandro Galiano Angela Vestito Angela De Lisio Pia Clara Pafundi Ferdinando Carlo Sasso Salvatore Cappabianca Gianfranco Nicoletti Giuseppe Paolisso Raffaele Marfella 《JACC: Cardiovascular Imaging》2021,14(2):426-438
ObjectivesThis study sought to determine whether the breast gland adipose tissue is associated with different rates of major adverse cardiac events (MACEs) in pre-menopausal women.BackgroundTo our knowledge, no study investigated the impact of breast adipose tissue infiltration on MACEs in pre-menopausal women.MethodsProspective multicenter cohort study conducted on pre-menopausal women >40 years of age without cardiovascular disease and breast cancer at enrollment. The study started in January 2000 and ended in January 2009, and the end of the follow-up for the evaluation of MACEs was in January 2019. Participants underwent mammography to evaluate breast density and were divided into 4 groups according to their breast density. The primary endpoint was the probability of a MACE at 10 years of follow-up in patients staged for different breast deposition/adipose tissue deposition.ResultsThe propensity score matching divided the baseline population of 16,763 pre-menopausal women, leaving 3,272 women according to the category of breast density from A to D. These women were assigned to 4 groups of the study according to baseline breast density. At 10 years of follow-up, we had 160 MACEs in group 1, 62 MACEs in group 2, 27 MACEs in group 3, and 16 MACEs in group 4. MACEs were predicted by the initial diagnosis of lowest breast density (hazard ratio: 3.483; 95% confidence interval: 1.476 to 8.257). Further randomized clinical trials are needed to translate the results of the present study into clinical practice. The loss of ex vivo breast density models to study the cellular/molecular pathways implied in MACE is another study limitation.ConclusionsAmong pre-menopausal women, a higher evidence of adipose tissue at the level of breast gland (lowest breast density, category A) versus higher breast density shows higher rates of MACEs. Therefore, the screening mammography could be proposed in overweight women to stage breast density and to predict MACEs. (Breast Density in Pre-menopausal Women Is Predictive of Cardiovascular Outcomes at 10 Years of Follow-Up [BRECARD]; NCT03779217) 相似文献
95.
Tamagno G Maffei P Pasquali C De Carlo E Martini C Mioni R Crivellaro C Faggian D Pedrazzoli S Sicolo N 《Scandinavian journal of gastroenterology》2005,40(12):1497-1501
Cystic endocrine tumors of the pancreas rarely occur, and only a few cases of cystic insulinoma have been reported to date. Diagnosis of insulinoma could be difficult if the functional activity is incomplete, possibly leading to blunted symptoms of hypoglycemia and failure in the laboratory to provide evidence of hyperinsulinemia. We report a clinical case of cystic insulinoma confirmed by histological examination after surgery, characterized by a high intracystic insulin concentration despite normal blood basal levels of the hormone. New diagnostic findings from dynamic tests and cystic fluid examination have been carefully focused on. 相似文献
96.
G. Volpe B. Gamberi C. Pastore A. Roetto M. Pautasso G. Parvis C. Camaschella U. Mazza G. Saglio G. Gaidano 《Annals of hematology》1996,72(2):67-71
Microsatellite instability (MSI) represents one specific pattern of genomic instability and is one of the genetic lesions most frequently detected in human neoplasia. Although MSI has been found to be associated with a wide variety of solid cancers, its involvement in lymphoid malignancies is virtually unexplored. In this study, we have investigated the presence of MSI in chronic lymphoproliferative disorders by comparing the pattern of nine microsatellite repeats (two tetranucleotides, two trinucleotides, and five dinucleotides) on autologous germline and tumor DNA of 23 patients, including 17 with B-cell chronic lymphocytic leukemia/small lymphocytic lymphoma (B-CLL/SLL), four with hairy cell leukemia, one with lymphoplasmacytoid lymphoma, and one with T-cell chronic lymphocytic leukemia. All samples at diagnosis displayed a germline pattern of the microsatellites examined, thus suggesting that MSI is not involved in the pathogenesis of these lymphoproliferations. Also, no microsatellite alterations were observed in consecutive samples of B-CLL/SLL obtained from the same patient at various stages of the disease both before and after chemotherapy. Conversely, alterations in 3/9 microsatellite repeats were detected in one case of Richter's syndrome which had evolved from a pre-existent B-CLL/SLL phase. Overall, the low frequency of MSI among chronic lymphoproliferative disorders adds further weight to the common view that the mechanisms and patterns of genomic instability in lymphoid neoplasia differ markedly from those commonly observed in solid cancers. 相似文献
97.
98.
99.
Gianluca Marucci Alessandra Maresca Leonardo Caporali Anna Farnedi Christine Margaret Betts Luca Morandi Dario de Biase Serenella Cerasoli Maria Pia Foschini Elena Bonora Michele Vidone Giovanni Romeo Elena Perli Carla Giordano Giulia d'Amati Giuseppe Gasparre Agostino Baruzzi Valerio Carelli Vincenzo Eusebi 《Human pathology》2013
100.
Edoardo Conte Daniele Andreini Marco Magnoni Serge Masson Saima Mushtaq Sergio Berti Mauro Canestrari Giancarlo Casolo Domenico Gabrielli Roberto Latini Paolo Marraccini Tiziano Moccetti Maria Grazia Modena Gianluca Pontone Marco Gorini Aldo P. Maggioni Attilio Maseri 《Journal of Cardiovascular Computed Tomography》2021,15(1):73-80
BackgroundHigh-risk coronary atherosclerosis features evaluated coronary CT angiography (CCTA) were suggested to have a prognostic role. The present study aimed to evaluate the association of circulating biomarkers with high-risk plaque features assessed by CCTA.MethodsA consecutive cohort of subjects who underwent CCTA because of suspected CAD was screened for inclusion in the CAPIRE study. Based on risk factors (RF) burden patients were defined as having a low clinical risk (0–1 RF with the exclusion of patients with diabetes mellitus as single RF) or an high clinical risk (≥3 RFs). In all patients, measurement of inflammatory biomarkers and CCTA analysis focused on high-risk plaque features were performed. Univariate and multivariate logistic regression analysis were used to evaluate the relationship between clinical and biological variables with CCTA advanced plaque features.Results528 patients were enrolled in CAPIRE study. Older age and male sex appeared to be predictors of qualitative high-risk plaque features and associated with the presence of elevated total, non-calcified and low-attenuation plaque volume. Among circulating biomarkers only hs-CRP was found to be associated with qualitative high-risk plaque features (OR 2.02, p = 0.004 and 2.02, p = 0.012 for LAP and RI > 1.1, respectively) with borderline association with LAP-Vol (OR 1.52, p = 0.076); HbA1c and PTX-3 resulted to be significantly associated with quantitative high-risk plaque features (OR 1.71, p = 0.003 and 1.04, p = 0.002 for LAP-Vol, respectively).ConclusionsOur results support the association between inflammatory biomarkers (hs-CRP, PTX- 3), HbA1c and high-risk atherosclerotic features detected by CCTA. Male sex and older age are significant predictors of high-risk atherosclerosis. 相似文献