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61.
Circulating mitochondrial DNA increases with age and is a familiar trait: Implications for “inflamm‐aging”
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Marcello Pinti Elisa Cevenini Milena Nasi Sara De Biasi Stefano Salvioli Daniela Monti Stefania Benatti Lara Gibellini Rodolfo Cotichini Maria Antonietta Stazi Tommaso Trenti Claudio Franceschi Andrea Cossarizza 《European journal of immunology》2014,44(5):1552-1562
Mitochondrial components, including mitochondrial DNA (mtDNA), when released extracellularly, can act as “damage‐associated molecular pattern” (DAMP) agents and cause inflammation. As many elderly people are characterized by a low‐grade, chronic inflammatory status defined “inflamm‐aging,” we evaluated if circulating mtDNA can contribute to this phenomenon. Eight hundred and thirty‐one Caucasian subjects were enrolled in the study, including 429 siblings aged 90–104 (90+ siblings). mtDNA plasma levels increased gradually after the fifth decade of life. In 90+ subjects, mtDNA values of two members of the same sibling relationship were directly correlated, suggesting a role for familiar/genetic background in controlling the levels of circulating mtDNA. The subjects with the highest mtDNA plasma levels had the highest amounts of TNF‐α, IL‐6, RANTES, and IL‐1ra; the subjects with the lowest mtDNA levels had the lowest levels of the same cytokines. In vitro stimulation of monocytes with mtDNA concentrations similar to the highest levels observed in vivo resulted in an increased production of TNF‐α, suggesting that mtDNA can modulate the production of proinflammatory cytokines. Our findings therefore show that circulating mtDNA increases with age, and can significantly contribute to the maintenance of the low‐grade, chronic inflammation observed in elderly people. 相似文献
62.
Luigi Nappi Ugo Indraccolo Attilio Di Spiezio Sardo Giorgio Gentile Katia Palombino Maria Antonietta Castaldi Marialuigia Spinelli Pantaleo Greco 《Journal of minimally invasive gynecology》2009,16(2):157-162
Study ObjectiveTo investigate whether diabetes, hypertension (HTN), and obesity can be considered risk factors for endometrial polyps (EPs) independently of age and menopausal status.DesignRetrospective analysis (Canadian Task Force classification III).SettingDepartment of Obstetrics and Gynecology of the University of Foggia, Italy.PatientsA total of 353 Caucasian women undergoing office hysteroscopy to assess abnormal uterine bleeding, infertility, cervical polyps, and abnormal sonographic patterns.InterventionsDemographic characteristics and data on diabetes, HTN, and menopausal status were collected and anthropometric parameters were analyzed. Vaginoscopic hysteroscopy was performed with a 5-mm continuous-flow operative office hysteroscope. When present, EPs were treated during the same procedure by means of 5-Fr scissors or electrode.Measurements and Main ResultsIn 134 (38%) of 353 cases, EPs were found. Univariable and multivariable analysis were performed to verify the presence of a statistically significant association among age, menopause, HTN, obesity, diabetes (independent variables), and the presence of EPs. Univariable logistic analysis showed a statistically significant association among age, menopause, HTN, obesity, and the presence of EPs. However, when multivariable logistic regression was performed, all the independent variables, except age, lost statistical significance (OR 1.05, 95% CI 1.02–1.07, p <.001).ConclusionAlthough it appears that EP is a disorder of aging, the significance of diabetes, HTN, and obesity, as well as menopause, on the development of EPs should be reconsidered. 相似文献
63.
Vito Michele Lauta M. Antonietta De Sangro 《Medical oncology (Northwood, London, England)》1995,12(4):223-230
Thirty-three patients with II type mixed essential cryoglobulinemia (MEC) were randomized into two groups: one to receive combined therapy including prednisone plus interferon, the other to receive prednisone therapy. Interferon was administered as induction treatment (3 Mu/day) and then as maintenance therapy (3 Mu three times a week). 83% of the combined therapy patients responded as opposed to 27% of the prednisone treated patients. Among the patients that responded to combined therapy, nine of them had a complete response, four a partial response, and two a minor response. None of the patients treated with prednisone therapy responded completely but only two had a partial and two a minor response. Four patients (three of combined therapy and one of prednisone therapy) showed proteinuria before the treatment which improved at the end of the induction therapy. Ten patients showed anti-HCV positivity which remained unchanged after the treatment. Three patients showed liver involvement secondary to cryoglobulinemia and an improvement of histological pattern after the induction with combined therapy. One patient showed an improvement of peripheral neuropathy after induction with the combined therapy. These data suggest the effectiveness of interferon given as induction and as maintenance treatment in the therapy of II type mixed essential cryoglobulinemia. 相似文献
64.
Martelli A Carrozzino R Mattioli F Brambilla G 《Toxicology and applied pharmacology》2002,182(3):219-225
4,4'-Methylenedianiline (MDA), an aromatic amine used in various industrial processes and previously found to induce tumor development in liver and thyroid of mice and rats, was evaluated for its DNA-damaging activity in primary cultures of hepatocytes and thyreocytes from rat and human donors. After exposure for 4 and 20 h to MDA concentrations ranging from 10 to 180 microM, a statistically significant increase in the frequency of DNA lesions was revealed by the Comet assay in primary hepatocytes and thyreocytes from donors of both species, the response being dose dependent up to 56-100 microM MDA. DNA fragmentation was more marked after 4 than after 20 h exposure in all four cell types. DNA was damaged to a lesser extent in human hepatocytes and thyreocytes than in corresponding rat cells and in both species in hepatocytes than in thyreocytes. In both rat and human hepatocytes a 20-h exposure to the same MDA concentrations elicited a modest amount of DNA repair synthesis, as evaluated by autoradiography. Evidence of a partial reduction of DNA damage, and therefore of only partial DNA repair, was observed in rat hepatocytes and in rat and human thyreocytes incubated for 16 h in MDA-free medium after a 4-h MDA treatment. A 4-h exposure to 56, 100, and 180 microM MDA did not induce DNA lesions in primary cultures of cells from three rat organs, kidney, urinary bladder mucosa, and brain, which are resistant to MDA carcinogenic activity. Under the same experimental conditions any evidence of DNA damage was absent in primary kidney and urinary bladder cells from human donors. Taken as a whole the results of this work indicate that MDA is specifically activated to DNA-damaging reactive species by hepatocytes and thyreocytes in both rats and humans and thus suggest that liver and thyroid might be the targets of the carcinogenic activity of MDA also in humans. 相似文献
65.
Potassium canrenoate (PC), a competitive aldosterone antagonist previously found to increase tumor incidence in rats and to produce genotoxic effects in in vitro systems, was examined in rats to acquire information on its genotoxic activity in vivo. Intragastric administration of 1/2 LD50 produced, as revealed by the Comet assay, a modest but statistically significant increase in the frequency of DNA lesions in liver but not in thyroid and bone marrow of male rats, and in thyroid and bone marrow but not in liver of female rats. In contrast with the frankly positive responses observed in primary cultures of rat hepatocytes (Martelli et al., Mutagenesis 14 (1999) 463-472) any evidence of DNA repair and micronuclei formation was absent in liver of rats treated with 1/2 LD50, and initiation of enzyme-altered liver preneoplastic lesions did not occur in the liver of rats given 100 mg/kg PC once a week for 6 successive weeks. A high and dose-dependent frequency of DNA lesions was found to occur in testes and ovaries of rats given single doses ranging from 1/8 to 1/2 LD50. 相似文献
66.
67.
De Simone R Ajmone-Cat MA Tirassa P Minghetti L 《Journal of neuropathology and experimental neurology》2003,62(2):208-216
The interaction of phosphatidylserine (PS), exposed on the surface of apoptotic cells and with its specific receptor (PtdSerR) expressed by microglia, is a crucial event in the recognition and clearance of apoptotic neurons. Here, we extend our previous studies in which PS-liposomes mimicking apoptotic cells were used to investigate the functional role of PS-PtdSerR interactions on microglial functional state. Purified rat microglial cells were either incubated with PC12 cells maintained in complete medium (healthy), exposed to staurosporine or serum deprivation (apoptotic), or treated with hydrogen peroxide (necrotic). After 24 hours, supernatants from co-cultures and single cell type cultures were analyzed for nitric oxide (NO), tumor necrosis factor-alpha (TNF-alpha), interleukin-10 (IL-10), prostaglandin E2 (PGE2), transforming growth factor-beta1 (TGF-beta1), and nerve growth factor (NGF). When lipopolysaccharide (LPS)-activated microglia was cultured with apoptotic PC12 cells, NO and TNF-alpha levels significantly decreased, IL-10 was not affected, and PGE2 levels were substantially increased. In addition, TGF-beta and NGF syntheses increased when resting microglia was cultured with apoptotic but not healthy or necrotic PC12 cells. We proposed that upon interaction with PS-expressing apoptotic neurons, microglia no longer act as a promoter of the inflammatory cascade and that the specific microglial functional state induced by PS-PtdSerR may be relevant for the final outcome of neurodegenerative diseases. 相似文献
68.
Casati V Sandrelli L Speziali G Calori G Grasso MA Spagnolo S 《The Journal of thoracic and cardiovascular surgery》2002,123(6):1084-1091
OBJECTIVE: We studied the hemostatic effects of tranexamic acid in patients undergoing elective surgery involving the thoracic aorta. METHODS: In a double-blind, randomized fashion, 60 consecutive patients were assigned to two treatment groups: 30 patients (placebo group) received infusion of saline solution, and 30 (treatment group) received tranexamic acid (1 g before skin incision, an infusion of 400 mg/h during the operation, and 500 mg in the pump priming). Perioperative bleeding was considered as a primary outcome. Perioperative allogeneic transfusions, major thrombotic complications (myocardial infarction, pulmonary embolism, renal insufficiency), and surgical outcomes were also considered. RESULTS: Patients treated with tranexamic acid showed significant reductions in postoperative bleeding, both in terms of the amount collected during the first 4 postoperative hours (median 307 mL, interquartile range 253-361 mL in the placebo group vs median 211 mL, interquartile range 108-252 mL in the treatment group, P =.002) and in terms of total bleeding (median 722 mL, interquartile range 574-952 mL in the placebo group vs median 411 mL, interquartile range 313-804 mL in the treatment group, P =.04). Consequently, the number of patients transfused differed significantly between groups (21 patients [72.4%] in the placebo group vs 13 [44.8%] in the treatment group, P =.033). Patients in the treatment group showed significant reductions in the total amount for the entire group of packed red cells transfused (13,500 mL in the treatment group vs 28,000 mL in the placebo group, P =.012) and in the total amount of allogeneic transfusions (23,400 mL in the treatment group vs 53,000 mL in the placebo group, P =.024). No differences in perioperative thrombotic complications were found. CONCLUSIONS: In this initial series of patients undergoing thoracic aortic surgery, tranexamic acid appeared effective in reducing perioperative bleeding, with a significant reduction in the need for allogeneic transfusions and without any increased risk of thrombotic complications. 相似文献
69.
Casati V Speziali G D'Alessandro C Cianchi C Antonietta Grasso M Spagnolo S Sandrelli L 《Anesthesiology》2002,97(2):367-373
BACKGROUND: Recently, various studies have questioned the efficacy of intraoperative acute normovolemic hemodilution (ANH) in reducing bleeding and the need for allogeneic transfusions in cardiac surgery. The aim of the present study was to reevaluate the effects of a low-volume ANH in elective, adult open-heart surgery. METHODS: Two hundred four consecutive adult patients undergoing cardiac surgery were prospectively randomized in a nonblinded manner into two groups: ANH group (103 patients), where 5-8 ml/kg of blood was withdrawn before systemic heparinization and replaced with colloid solutions, and a control group, where no hemodilution was performed (101 patients). Procedures included single and multiple valve surgery, aortic root surgery, coronary surgery combined with valve surgery, or partial left ventriculectomy. The purpose of the study was to evaluate the efficacy of ANH in reducing the need for allogeneic blood components. Routine hematochemical evaluations, perioperative blood loss, major complications, and outcomes were also recorded. RESULTS: No differences were found between the groups regarding demographics, baseline hematochemical data, and operative characteristics. There was no difference in the amount of transfusions of packed red cells, fresh frozen plasma, platelet concentrates, total number of patients transfused (control group, 36% vs. ANH group, 34.3%; P = 0.88), and amount of postoperative bleeding (control group, 412 ml [313-552 ml] vs. ANH group, 374 ml [255-704 ml]) (median [25th-75th percentiles]); P = 0.94. Further, perioperative complications, postoperative hematochemical data, and outcomes were not different. CONCLUSIONS: In patients undergoing elective open-heart surgery, low-volume ANH showed lack of efficacy in reducing the need for allogeneic transfusions and postoperative bleeding. 相似文献
70.
Pizzichetta MA Talamini R Piccolo D Trevisan G Veronesi A Carbone A Soyer HP 《Tumori》2002,88(3):234-238
AIM AND BACKGROUND: Dermoscopic diagnosis of pigmented skin lesions is based on the evaluation of dermoscopic criteria (classical pattern analysis) and on alternative diagnostic methods, such as the ABCD (A, asymmetry; B, border; C, color; D, differential structures) rule based on the total dermatoscopic score. The aim of the study was to investigate the interobserver agreement of standard dermoscopic criteria between two observers and the diagnostic validity of dermoscopic diagnosis by pattern analysis and by the ABCD rule. STUDY DESIGN: The study included a total of 129 small (< or = 5 mm) melanocytic skin lesions selected from all lesions observed in consecutive patients between April 1996 and September 1998. Before surgery, each lesion was photographed with a Dermaphot. Dermoscopic images were examined independently by two observers to evaluate the presence or absence of standard dermoscopic criteria and to establish the dermoscopic diagnosis by pattern analysis and by the ABCD rule. RESULTS: Interobserver agreement for dermoscopic criteria varied from moderately good to good, with the highest agreement for radial streaks (k = 0.96) and the lowest for pseudopods (k = 0.49). Interobserver agreement was moderately good in dermoscopic diagnosis by pattern analysis (k = 0.48) and by the total dermatoscopic score (k = 0.44). The sensitivity and specificity of dermoscopic diagnosis by pattern analysis were 40% and 99%, respectively, for both observers. As regards the total dermatoscopic score (a cutoff score of < or = 5.45 vs > 5.45), sensitivity ranged from 80% to 100% and specificity from 48% to 59%. CONCLUSIONS: The study showed that the pattern analyses as well as the ABCD rule give a poor discrimination between benign and malignant lesions and do not add relevant information for management decision in small melanocytic lesions. However, close follow-up examinations of small equivocal melanocytic lesions using digital equipment allow evaluation of their dermoscopic features during progression and whether their rather commonly found atypical dermoscopic features are lost during their natural course of growth. 相似文献