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81.
82.
Dr Franco Testore Simona Milanese Marco Ceste Enrico de Conciliis Giuseppe Parello Claudio Lanfranco Roberto Manfredi Gianfranco Ferrero Carlotta Simoni Loredana Miglietta Silvia Ferro Lorena Giaretto Giuseppina Bosso 《Am J Cardiovasc Drugs》2008,8(4):257-263
BACKGROUND AND OBJECTIVE: Anthracyclines are highly effective and widely used cytotoxic agents, but their application is often limited by cumulative dose-dependent cardiotoxicity. Dexrazoxane has been shown in several clinical trials to prevent the development of this serious toxicity. The aim of our study was to analyze the incidence of cardiac dysfunction over a 10-year period in patients with breast cancer who were treated with anthracycline-based regimens with addition of dexrazoxane, mainly in an adjuvant setting. METHODS: We conducted a retrospective analysis on a population of women with breast cancer treated at our institution between January 1993 and October 2003. We reviewed patients' medical records and data on patient characteristics, treatment history, and adverse events that were collected, starting from the time of first visit before starting therapy, with the use of software created and designed for clinical records management in our institution (1999 OK-DHtrade mark). Patients underwent an ECG assessment prior to starting chemotherapy, and were clinically monitored for cardiac failure. Those who developed signs and symptoms suggestive of cardiac dysfunction underwent further ECG. If clinical findings indicated, echocardiography and further cardiologic investigations were performed. The main outcome measure was the development of signs and symptoms indicative of congestive heart failure (CHF). RESULTS: A total of 318 female patients were treated with an anthracycline (doxorubicin or epirubicin)-based combination chemotherapy regimen during this time, in most cases in the adjuvant setting (n = 285). Most patients (n = 302) had early-stage disease and only 16 women presented with metastatic disease with good life expectancy (at least 1 year). All patients received dexrazoxane 1000 mg/m(2) intravenously prior to anthracycline administration during each chemotherapy cycle. The median follow-up duration was 35 months. During this time, five patients (1.57%) developed signs and symptoms of CHF. No patient at our institution died of heart failure during the period analyzed. Dexrazoxane was well tolerated, with no reports of adverse events associated with this drug. CONCLUSIONS: The reported incidence of cardiotoxicity in this study represents a marked reduction compared with historical data for patients receiving anthracycline-based chemotherapy without dexrazoxane. Dexrazoxane appears to have a cardioprotective effect in women with early-stage or advanced breast cancer treated with anthracycline-based combination chemotherapy, mainly as an adjuvant treatment. Prospective, randomized, controlled clinical trials in adjuvant setting should be performed to confirm these results. 相似文献
83.
Cosimo Sperti Carmelo Militello Roubik Behboo Edwin Khajeturian Sergio Pedrazzoli Antonio Perasole Rita Alaggio Lucio Rovati 《Journal of surgical oncology》1994,57(1):11-16
The effects of the cholecystokinin (CCK)-analogue, caerulein, and CCK-receptor antagonist lorglumide (CR-1409) on pancreatic carcinogenesis induced by 7,12-dimethylbenz(a)anthracene (DMBA) were studied. One hundred thirty rats were divided into the following 10 treatment groups: group 1, DMBA (2–3 mg); group 2, DMBA + caerulein (5 μg/kg); group 3, DMBA + caerulein + CR-1409 (12 mg/kg); group 4, caerulein + DMBA; group 5, caerulein + CR-1409 + DMBA; group 6, DMBA + CR-1409; group 7, CR-1409 + DMBA; group 8, caerulein; group 9, CR-1409; and group 10, sham operation + saline. DMBA was surgically implanted into the pancreas. Caerulein and/or CR-1409 was administered twice daily for 15 days after (in groups 2, 3, and 6) or before (in groups 4, 5, and 7) DMBA implantation. Six months after carcinogen administration, all rats were sacrificed and autopsied. The incidence of pancreatic cancer appeared significantly (P < 0.001) increased when caerulein was administered following DMBA implantation. CR-1409 significantly inhibited (P < 0.02) caerulein effects and reduced tumor growth when injected after carcinogen exposure. © 1994 Wiley-Liss, inc. 相似文献
84.
Effect of prolonged incubation with copper on endothelium-dependent relaxation in rat isolated aorta
Chiarugi A Pitari GM Costa R Ferrante M Villari L Amico-Roxas M Godfraind T Bianchi A Salomone S 《British journal of pharmacology》2002,136(8):1185-1193
1 We investigated the effects of prolonged exposure to copper (Cu(2+)) on vascular functioning of isolated rat aorta. 2 Aortic rings were exposed to CuSO(4) (3-24 h) in Dulbecco's modified Eagle medium with or without 10% foetal bovine serum (FBS) and then challenged with vasoconstrictors or vasodilators in the absence of Cu(2+). 3 Exposure to 2 micro M Cu(2+) in the absence of FBS did not modify the response to phenylephrine (PE) or acetylcholine (ACh) in aortic rings incubated for 24 h. Identical exposure in the presence of FBS increased the contractile response to 1 micro M PE by 30% (P<0.05) and impaired the relaxant response to 3 micro M ACh or 1 micro M A23187 (ACh, from 65.7+/-7.1 to 6.2+/-1.1%, n=8; A23187, from 74.6+/-8.2 to 12.0+/-0.8%, n=6; P<0.01 for both). Cu(2+) exposure did not affect the relaxant response to NO-donors. 4 Impairment of vasorelaxation appeared 3 h after incubation with 2 micro M Cu(2+) and required 12 h to attain a steady state. Vasorelaxation to ACh was partially restored by 1 mM tiron (intracellular scavenger of superoxide ions; maximum relaxation 34.2+/-6.4%, n=10, P<0.01 vs Cu(2+) alone), whereas catalase, superoxide dismutase or cycloheximide were ineffective. 5 Twenty-four hour-exposure to 2 micro M Cu(2+) did not affect endothelium integrity or eNOS expression, and increased the Cu content in arterial rings from 6.8+/-1.1 to 18.9+/-2.9 ng mg(-1) wet weight, n=8; P<0.01. 6 Our results show that, in the presence of FBS, prolonged exposure to submicromolar concentrations of Cu(2+) impaired endothelium-dependent vasorelaxation in aortic rings, probably through an intracellular generation of superoxide ions. British Journal of Pharmacology (2002) 136, 1185-1193 相似文献
85.
Cappellacci L Barboni G Palmieri M Pasqualini M Grifantini M Costa B Martini C Franchetti P 《Journal of medicinal chemistry》2002,45(6):1196-1202
1'-C-Methyl analogues of adenosine and selective adenosine A(1) receptor agonists, such as N-[(1R)-1-methyl-2-phenylethyl]adenosine ((R)-PIA) and N(6)-cyclopentyladenosine, were synthesized to further investigate the subdomain that binds the ribose moiety. Binding affinities of these new compounds at A(1) and A(2A) receptors in rat brain membranes and at A(3) in rat testis membranes were determined and compared. It was found that the 1'-C-methyl modification in adenosine resulted in a decrease of affinity, particularly at A(1) and A(2A) receptors. When this modification was combined with N(6) substitutions with groups that induce high potency and selectivity at A(1) receptors, the high affinity was in part restored and the selectivity was increased. The most potent compound proved to be the 1'-C-methyl analogue of (R)-PIA with a K(i) of 23 nM for the displacement of [(3)H]CHA binding from rat brain A(1) receptors and a > 435-fold selectivity over A(2A) receptors. In functional assays, these compounds inhibited forskolin-stimulated adenylate cyclase with IC(50) values ranging from 0.065 to 3.4 microM, acting as full agonists. Conformational analysis based on vicinal protonminus signproton J-coupling constants and molecular mechanics calculations using the MM2 force field proved that the methyl group on C1' in adenosine has a pronounced impact on the furanose conformation by driving its conformational equilibrium toward the north, gamma+, syn form. 相似文献
86.
In the present study, we have analyzed the expression of nitric oxide synthase (NOS) in the preoptic-hypothalamo-hypophyseal system of the teleost Oreochromis niloticus. The assay for enzyme activity demonstrated that a constitutive NOS activity is present both in soluble and particulate fractions of the homogenates of diencephalons. Western blot analysis using an antibody against the N-terminus of human nNOS revealed two bands both in the supernatant and in the pellet. One band co-migrates at approximately 150 kDa with that detected in the rat cerebellum homogenates and presumably corresponds to neuronal NOS (nNOS) of mammals. The additional band, which migrates at approximately 180 kDa, might be attributed to an alternatively spliced nNOS isoform. Using NADPH diaphorase (NADPHd) histochemistry in combination with NOS immunohistochemistry, nNOS expression has been detected in preoptic nuclei, hypophysiotrophic nuclei of the ventral hypothalamus, and the pituitary gland. Various degrees of dissociation of NADPHd activity and nNOS immunoreactivity have been detected that could be attributed to the expression of different subtypes of nNOS in the preoptic/hypothalamo/hypophysial system of tilapia. In this paper, we also investigated the colocalization of nNOS with arginine-vasotocin (AVT) by means of immunolabeling of consecutive sections. Results suggest that NO may be colocalized with AVT in a subpopulation of neurosecretory neurons. Present findings suggest that nitric oxide (NO) is implicated in the modulation of hormone release in teleosts in a similar way to mammals. 相似文献
87.
Selective cytotoxicity of betulinic acid on tumor cell lines, but not on normal cells. 总被引:7,自引:0,他引:7
Valentina Zuco Rosanna Supino Sabina C Righetti Loredana Cleris Edoardo Marchesi Carlo Gambacorti-Passerini Franca Formelli 《Cancer letters》2002,175(1):17-25
Betulinic acid is a triterpene with selective cytotoxicity against melanoma, neuroectodermal and malignant brain tumor cell lines. In this study the betulinic acid activity was evaluated, in comparison with doxorubicin, on different human neoplastic and non-neoplastic cell lines and on proliferating normal lymphocytes. Growth inhibition was evident in all the neoplastic cell lines independently on p53 status and histotype. Antiproliferative activity of betulinic acid was related to a cytotoxic effect on two p53 wild-type and on one p53 mutant cell lines and to a cytostatic effect on one p53 mutant melanoma clone. At the same concentrations, normal cells were unaffected indicating a selective effect of this agent. A cytotoxic activity of doxorubicin was evident on all the tested systems. In vivo experiments, performed on one of these cell lines, confirmed the antineoplastic activity of this drug. These data support further preclinical studies of betulinic acid not confined to melanoma and neuroectodermal tumors independently of p53 status. 相似文献
88.
Tagliabracci A Turchi C Buscemi L Sassaroli C 《International journal of legal medicine》2001,114(4-5):224-228
Mitochondrial DNA sequences of the hypervariable regions HVI and HVII were analysed in 83 Caucasians living in central Italy
to expand the database for forensic identification purposes, and 75 different haplotypes resulting from 62 polymorphic positions
in HVI and 44 in HVII were observed. The most frequent haplotype (263G, 309.1C, 315.1C) was shared by 7 individuals, 2 haplotypes
were shared by 2 individuals, and 72 were unique. The genetic diversity was found to be 0.99 and the random match probability
1.9%. A condition of sequence heteroplasmy was found in only one case at nt 16311, whereas a length heteroplasmy was found
in the homopolymeric stretch of cytosines 303–315. Our results indicate that in direct sequencing beyond the poly-cytosine
stretch, the overlap is due to length heteroplasmy, whereas the blurred signal occurs when the stretch is composed of more
than 10 cytosines.
Received: 14 February 2000 / Accepted: 23 May 2000 相似文献
89.
Materia E Cacciani L Bugarini G Cesaroni G Davoli M Mirale MP Vergine L Baglio G Simeone G Perucci CA 《European journal of public health》2005,15(4):411-417
BACKGROUND: The relationship between income inequality and health remains controversial in terms of whether or not it exists and, if so, its extent and the mechanisms involved. This study examines the relationship between income inequality, as indicated by the Gini coefficient, and mortality in Italy. METHODS: Cross-sectional ecological study on the 57,138,489 inhabitants living in the 95 provinces existing in Italy in 1994. Multivariate weighted regression analysis of total and age-specific mortality, income inequality, gender, and interaction between income inequality and median income or geographical area. RESULTS: A positive association between income inequality and total mortality was observed for both genders in provinces with a low per capita income and in Southern and Central Italy. The effect was present for infants and for persons over 24 years of age; it was marked for the elderly, particularly women. A negative association with mortality was observed for males living in the North-west. Interactions between income inequality and median income, and between income inequality and geographical area were found. CONCLUSION: In Italy, the relationship between income inequality and health is mixed and not universal, in so far as a positive association was observed only in provinces with lower absolute income. Elderly persons living in Southern Italy represent the population subgroup most vulnerable to unequal income distribution. Income inequality can, in part, explain the historically higher mortality among women in Southern Italy compared to women in the North. These results indicate that income inequality affects the health of population subgroups differentially. 相似文献
90.
Memoli B Grandaliano G Soccio M Postiglione L Guida B Bisesti V Esposito P Procino A Marrone D Michael A Andreucci M Schena FP Pertosa G 《Journal of the American Society of Nephrology : JASN》2005,16(4):1099-1107
Soluble gp130 (sgp130) is a soluble circulating receptor of IL-6 with "antagonistic" biologic activity. It is generated independently by either shedding of the extracellular domain of membrane gp130 or alternative mRNA splicing. This study was addressed to clarify the mechanisms underlying sgp130 synthesis and release in patients who undergo regular dialysis treatment (RDT) using dialytic membranes with different biocompatibility. Two groups of RDT patients were enrolled: 11 patients who were treated with cellulosic membranes (C) and 10 patients who were treated with synthetic membranes (S). Ten healthy subjects constituted the control group. Serum samples and peripheral blood mononuclear cells (PBMC) were harvested in all groups (before dialysis in RDT patients). PBMC were cultured for 24 h in the absence or presence of LPS. The serum levels of sgp130 were significantly higher in C group than in control and S patients (C, 603.1 +/- 89.9; control, 396 +/- 49.5; S, 423.4 +/- 27.7 ng/ml; P < 0.01). PBMC from C patients, in the absence of any mitogenic stimulation, released a significantly greater amount of sgp130 as compared with S and control groups (C, 532.6 +/- 161.2; S, 332.4 +/- 148.6; control, 341.4 +/- 125.4 pg/ml; P < 0.01). The sgp130 release was positively correlated with the release of both IL-6 (r = 0.336, P < 0.05) and sIL-6R receptor (r = 0.324, P < 0.05). A significantly higher gp130 gene expression was also observed in unstimulated PBMC from C patients when compared with control and S groups. It is interesting that the expression of the 85-bp exon characteristic of the alternative splicing mRNA for sgp130 was low in all groups. Finally, confocal microscopy analysis showed an increased expression of gp130 on cell surface in unstimulated PBMC from C patients as compared with control and S groups. Our results demonstrate that in patients on RDT with C membranes, the synthesis and release of sgp130 "antagonistic" receptor is significantly increased. This release is seemingly due to a shedding of membrane-bound gp130 receptor. The increased sgp130 release may partially counteract the inflammatory effects caused by IL-6. 相似文献