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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
84.
L. Severi 《Journal of cancer research and clinical oncology》1954,59(6):679-686
Zusammenfassung Sowohl Mastopathia fibrocystica als auch Mamma-Fibroadenom sind morphologisch präcanceröse Gewebsveränderungen, aus denen sich besondere Krebse bilden.Die Brustkrebse können in folgender Weise unterteilt werden: Carcinoma ex fibroadenoma (16,09%), Carcinoma ex mastopathia (37,56%), von Fibroadenom und Mastopathie unabhängige Krebse (46,35%).Es wird aus gutem Grund angenommen, daß die Induktionszeit des Carcinoma ex fibroadenoma ungefähr 20 Jahre ausmacht, die des Carcinoma ex mastopathia ungefähr 8 Jahre beträgt.Zentrum für die Diagnose und Behandlung bösartiger Tumoren, Histopathologische Abteilung 相似文献
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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
86.
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
87.
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
88.
S Severi C Michelassi E Orsini P Marraccini A L'Abbate 《The American journal of cardiology》1989,64(14):889-895
A medical approach to treatment was adopted in 652 patients with documented myocardial ischemia at rest during both the acute and follow-up phases. No patient underwent coronary revascularization during hospitalization and only 86 patients (13%) underwent coronary bypass surgery within 8 months from discharge. During hospitalization 13 patients died. In the remaining group (639 patients), the likelihood of death in the 10-year period after discharge was 28% for all patients and 20% for cardiac causes only. A series of factors studied during the acute stage were assessed in an effort to predict long-term outcome. The following noninvasive characteristics, listed in decreasing order of statistical significance, were found to be significant univariate predictors of survival: abnormal basal electrocardiogram, duration of coronary artery disease, previous myocardial infarction, pattern of ST-T changes during episodes of ischemia at rest, age and systemic hypertension. The average annual mortality rate for patients with T-wave changes, ST-segment elevation and ST-segment depression was 0.9, 1.8 and 3%, respectively. The Cox survival analysis identified abnormal basal electrocardiogram, duration of coronary artery disease and pattern of ST-T changes as significant, independent predictors of death. When invasive characteristics were entered in the model, number of greater than or equal to 50% narrowed coronary arteries, left ventricular ejection fraction, abnormal basal electrocardiogram and smoking habit were found to be independent and additive prognostic variables. Thus, long-term prognosis of patients with ischemia at rest is related to the severity of anatomic impairment, independent of the pattern of ST-T changes observed during the acute phase.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
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