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11.
Modulatory effect of prolactin on the resting and mitogen-induced activity of T, B, and NK lymphocytes 总被引:4,自引:0,他引:4
Lina Matera Alessandra Cesano Graziella Bellone Emanuela Oberholtzer 《Brain, behavior, and immunity》1992,6(4):409-417
Prolactin (PRL) has been shown to contribute to the development of lymphoid tissues and maintenance of physiological immune function. Here we show that the role of the hormone extends to the control of the effector phase of the immune response. In addition to triggering resting lymphocytes to cell division, the hormone can also control the magnitude of their response to polyclonal stimuli. Concentrations of PRL in the physiological range increased the [3H]thymidine, [3H]uridine, and [3H]leucine incorporation of unstimulated NK cells cultured in serum-free conditions. The same concentrations of the hormone increased the response of NK, T, and B cells to the mitogenic stimuli interleukin 2 (IL2), phytohemagglutinin (PHA), and staphylococcus aureus cowan, respectively, the effect being maximally evident in the presence of suboptimal concentrations of the mitogens. By contrast concentrations of PRL five- to tenfold the physiological levels inhibited the mitogenic response to IL2 and PHA. These data indicate a double-faceted regulatory role of this hormone in vivo. 相似文献
12.
Lucia Carvalho Monica Lipay Francisco Belfort Ivan Santos Joyce Andrade Alessandra Haddad Flavia Brunstein Lydia Ferreira 《Journal of plastic, reconstructive & aesthetic surgery》2006,59(9):961-968
BACKGROUND: Telomerase activity (TA) is believed to play a role in the regulation of senescence and to limit the number of cell divisions. The deregulation of telomerase appears to contribute to oncogenesis and the formation of immortal cell lines. As a result, it is believed that it could be used as a prognostic marker in melanoma. METHODS: TA was assayed by the polymerase chain reaction PCR-ELISA-based telomeric repeat amplification protocol (TRAP assay). One hundred and eight samples were distributed in four histological groups: 30 samples from primary cutaneous melanomas, 24 from peritumoural skin sites, 28 from benign melanocytic lesions, and 26 from normal skin sites as a control. RESULTS: TA was different among the four tested groups (Kruskall-Wallis test p<0.001), and increasing values of TA were observed progressing from normal skin to benign and then to malignant lesions. Among melanoma samples, there was a significant association between TA and ulceration (p=0.025), TA and vascular invasion (p=0.018) and TA and mitotic rate (p=0.029) (Mann-Whitney test). A linear regression analysis showed significant associations between the increase of TA with Breslow thickness (p=0.004) and the presence of satellites (p=0.002). CONCLUSIONS: We observed that TA had increased from control skin to peritumoural skin, and then to benign melanocytic lesions and finally to melanoma, suggesting tumour progression. TA showed higher values in the presence of some important histopathologic parameters related to poor prognosis in cutaneous melanoma such as ulceration, vascular invasion, satellites, high rates of mitosis, and in thicker tumours. 相似文献
13.
Inhibition by N-acetylcysteine of carcinogen-DNA adducts in the tracheal epithelium of rats exposed to cigarette smoke 总被引:1,自引:0,他引:1
Izzotti Alberto; Balansky Roumen; Scatolini Leonardo; Rovida Alessandra; De Flora Silvio 《Carcinogenesis》1995,16(3):669-672
The ability of the aminothiol N-acetylcysteine (NAC) to preventthe formation of carcinogen-DNA adducts in tracheal epithelialcells was investigated in Sprague-Dawley rats exposed whole-bodyto mainstream cigarette smoke for either 40 or 100 consecutivedays. 32P-Postlabelling analyses showed the occurrence of DNAadducts (12.49 adducts/108 nucleotides) after 40 days of exposure,with a trend to formation of characteristic diagonal radioactivezones. Total adduct levels were not further enhanced after 100days of exposure to smoke, although significant changes occurredin the amounts of individual adducts. NAC, given by gavage inthe 40 day study and in drinking water in the 100 day study,significantly inhibited the formation of smoke-related carcinogen-DNAadducts in the tracheal epithelium, to such an extent that adductlevels were not significantly higher than those detected insham-exposed control rats. Together with a variety of othermolecular, clastogenicity, metabolic, cytological and histopathologicalend-points investigated in rodents and with the preliminaryevidence arising from a study in humans, these results documentthe considerable efficacy of oral NAC in inhibiting smoke-relatedcarcinogen-DNA adducts. 相似文献
14.
Pierpaolo Sileri Vito Maria Stolfi Giampiero Palmieri Alessandra Mele Alessandro Falchetti Sara Di Carlo Achille Lucio Gaspari 《Journal of gastrointestinal surgery》2007,11(12):1662-1668
Stapled hemorrhoidopexy is widely accepted to treat hemorrhoids, but serious complications have been reported. In this prospective
audit, we correlated clinical outcome with pathological findings. From January 2003 to April 2007, 94 patients underwent hemorrhoidopexy.
Macroscopic appearance of the specimen (shape, size, and depth) was recorded. Microscopically, the presence of columnar, transitional,
and squamous epithelium, the involvement of circular/longitudinal smooth muscle, and features of mucosal prolapse were assessed.
Clinical outcome was evaluated by a validated questionnaire. Postoperative pain, secretion, and bleeding durations were 12.7 +/− 10.6,
5.6 +/− 9.6, and 6.3 +/− 8.4 days. Patient’s return to work averaged 16.7 +/− 10.7 days. Fissure, skin tags, and anal strictures
were observed in 23.4%. Seven patients experienced pain for a significantly longer period of time. All specimens contained
columnar mucosa, but 29.8% contained columnar and transitional epithelium and 12.8% contained columnar, anal transitional,
and stratified squamous epithelium. Smooth muscle was observed in 62.7%. Pain was significantly increased if transitional
epithelium was present in the specimen. No correlation or differences were observed if smooth muscle was present, although
postoperative bleeding was more frequent. Hemorrhoidopexy is safe and effective. The specimen should always be sent for pathology
examination. Only columnar epithelium should be present and, although the presence of smooth muscle does not influence the
outcome in terms of functional results, its presence may play a role in postoperative bleeding.
Presented as poster at the Digestive Disease Week, May 2007, Washington, USA 相似文献
15.
G. Fatati M. L. Amerio M. Bacci F. Brunetti A. Caretto L. Casali S. Coaccioli F. D’Andrea E. Del Toma M. Di Sapio D. Domeniconi M. Kob F. Leonardi E. Mirri P. Nanni A. Paci P. Pallini G. Ronzani A. R. Sabbatini S. G. Sukkar M. Tagliaferri G. Vincenzoni M. A. Fusco 《Mediterranean journal of nutrition and metabolism》2009,1(3):203-206
16.
17.
Giovanni Melioli Editta Baldini Maria Cristina Mingari Andrea De Maria Mario Roberto Sertoli Fausto Badellino Pier Luigi Percivale Alessandra Catturich Sergio Bertoglio Dario Civalleri Leonardo Santi Lorenzo Moretta 《International journal of cancer. Journal international du cancer》1989,43(2):231-234
In the course of a phase I trial, in which recombinant IL-2 (rIL-2) was infused intraperitoneally (i.p.) in patients with peritoneal carcinomatosis, we evaluated the effect on "tumor-associated lymphocytes" (TAL) isolated from the ascitic fluid. No major changes in the percentages of cells expressing the CD3, CD4, CD8, Leu-7, OKM1 and WT-31 antigens were detected either in TAL or in peripheral blood lymphocytes (PBL) after 7 days of rIL-2 infusion. In contrast the percentages of TAL (but not PBL) expressing surface IL-2 receptor (Tac), or LAK-1 antigen were sharply increased. Analysis of cytolytic functions showed a potentiation of the lytic activity against natural-killer (NK) sensitive K562 target cells and the de novo appearance of lytic activity against fresh melanoma cells. In one patient IFN-gamma was detected in the ascitic fluid following rIL-2 infusion. T-cell clones derived from the patient were analyzed for the IFN-gamma production. While only approximately 40% of PB-derived control clones produced medium to low amounts of IFN-gamma, all of the TAL-derived clones produced medium to high amounts of the lymphokine. 相似文献
18.
M. Abdellah Alaoui Jamali Ming-biao Yin Alessandra Mazzoni Issam Bankusli Youcef M. Rustum 《Cancer chemotherapy and pharmacology》1989,25(2):77-83
Summary The effect ofN-(3,4-dimethoxyphenyl)N-methyl-2-(naphthyl)-m-dithiane-2-propylamine hydrochloride (RO11-2933), an analog of the calcium channel blocker tiapamil, on doxorubicin (DOX)-induced cytotoxicity and DNA damage in human ovarian cancer cells sensitive and resistant to DOX was investigated. A2780-DX2, A2780-DX3, and A2780-DX6 cell sublines were characterized by 7-, 26-, and 48-fold resistance after 2 h DOX exposure and 30-, 50-, and 500-fold resistance after 72 h DOX exposure, respectively. Increased drug efflux resulting in a lower intracellular drug accumulation, decreased DOX-induced DNA single-strand breaks (DNA SSBs), and rapid DNA repair correlated with the degree of resistance. In addition, DNA SSBs were rapidly repaired within 8 h in A2780-DX3 cells, whereas no significant repair of DNA SSBs was observed in sensitive cells. In comparison with verapamil, RO11-2933 was found to reverse DOX resistance at lower and nontoxic concentrations (2 M as compared with 10 M verapamil). This reversion was complete in cells with a low degree of resistance (A2780-DX1 and A2780-DX2) but partial in highly resistant cells (A2780-DX3 and A2780-DX6), and continuous exposure to RO11-2933 was essential for optimal reversal of drug resistance. Interestingly, RO11-2933 was found to inhibit the repair of DNA SSBs induced by DOX but not those induced by X-ray. These results suggest that the potentiation of DNA SSBs and the specific inhibition of DNA repair by RO11-2933 in multidrug-resistant cells could be of particular value in overcoming MDR in the clinic.Abbreviations RO11-2933
N-(3,4-dimethoxyphenethyl)-N-methyl-2-(2-naphthyl)-m-dithiane-2-propylamine hydrochloride
- DOX
doxorubicin-HCl
- SSBs
single-strand breaks
- MDR
multidrug resistance
This work was supported in part by CA 18420 and CA 21071 相似文献
19.
Faravelli C Abrardi L Bartolozzi D Cecchi C Cosci F D'Adamo D Lo Iacono B Ravaldi C Scarpato MA Truglia E Rossi Prodi PM Rosi S 《Psychotherapy and psychosomatics》2004,73(4):226-234
BACKGROUND: It has been argued that lay interviewers' use of fully-structured interviews could lead to a diagnostic pattern different to that by treating physicians. Clinical interviewers in community samples should probably identify cases that are closer to those seen in clinical settings. The greatest advantage of using clinical interviewers consists of the immediate assessment of a possible psychopathology, i.e. the evaluation of current disorders. METHODS: Two thousand three hundred and sixty-three citizens from the community of Sesto Fiorentino, Italy, were interviewed by their own general practitioners using the Mini International Neuropsychiatric Interview (MINI). Positive cases for any lifetime psychiatric disorder as well as a random sample of the negative cases were re-interviewed by psychiatrists or trained residents in psychiatry using the Florence Psychiatric Interview (FPI). RESULTS: The point prevalence for any current disorder was 8.7%; the two disorders with the highest prevalence were generalised anxiety disorder (2.9%) and major depressive episode (2.7%). The figures increase about 50% when the sub-threshold sequelae of previous disorders are considered. Current comorbidity was generally high. The one-year prevalence of any disorder was 10.6%. Ninety-two percent of the cases sought help, 82% were being treated at the moment of interview. Social impairment was considerable. CONCLUSIONS: The period prevalence rates for most of the disorders considered were generally comparable with the range defined by previous studies conducted in other Western countries, despite using different methodologies. Conversely, the use of health facilities, the treatment received and the social impairment were much higher than those reported by the other studies, suggesting a greater similarity with the clinical samples. 相似文献
20.
Farilla L Tiberti C Luzzago A Yu L Eisenbarth GS Cortese R Dotta F Di Mario U 《European journal of immunology》2002,32(5):1420-1427
Autoantigenic epitope mapping represents a critical issue in autoimmune diseases. The islet tyrosine phosphatase-like protein IA-2/ICA512bdc is a major autoantigen in type 1 diabetes (IDDM), but the epitopes responsible for autoantibody binding have been only partially defined. The aim of our study was to identify ICA512bdc epitopes, and in particular mini-epitopes, utilizing a novel strategy for autoimmune diseases. The study was performed in three sequential steps: (1) construction of a lambda-phage surface-displayed ICA512bdc cDNA library with the methodology of tagged random priming with peptides displayed as a fusion to the C terminus of the capsid protein D; (2) affinity selection of the resulting library, followed by immunoscreening, enzyme-linked immunosorbent assay and sequence analysis of positive clones, and (3) radioimmunoprecipitation to detect autoantibodies to the selected clones. This strategy resulted in the identification of two epitopes (IA-2 residues 761 - 964 and 929 - 979), which were recognized by 100 % and 62.9 % ICA512bdc-positive IDDM patients, respectively. Interestingly, the larger clone was detected also by a proportion (16.7 %) of new onset ICA512bdc-negative patients, thus suggesting that this region contains not only the main autoantigenic repertoire of ICA512bdc molecule, but is able to detect IA-2 autoantibodies in even higher percentages of patients. In addition, this study showed the existence of multiple epitopes located in the C-terminal domain of the IA-2 protein, one of which is formed by the 50 C-terminal amino acids, and provided evidence that the strategy used represents a valid tool for identification of epitopes within autoantigenic molecules. 相似文献