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51.
In vitro and in vivo effects of cisplatin on the generation of lymphokine-activated killer cells 总被引:1,自引:0,他引:1
P Allavena P Pirovano C Bonazzi N Colombo A Mantovani M D'Incalci 《Journal of the National Cancer Institute》1990,82(2):139-142
Pretreatment of human peripheral blood lymphocytes (PBL) with cisplatin (CDDP) before in vitro culture with interleukin-2 (IL-2) inhibited the generation of lymphokine-activated killer (LAK) cells and strongly inhibited proliferation. This inhibition was dose dependent, was significant only at concentrations greater than 6 microM, and it required exposure to the drug for more than 1 hour. This period of IL-2 unresponsiveness was maximum at 6 hours, but was spontaneously recovered within 24-48 hours and was more rapidly restored by increasing dosages of IL-2. Because inhibition of the generation of LAK cells by CDDP was observed only at relatively high levels of exposure to the drug (greater than 6 microM for greater than 1 hr), it was important that we explore the in vivo significance of these findings. The peripheral blood lymphocytes from patients bearing ovarian adenocarcinoma collected 1 hour after an iv infusion of 50 mg of CDDP/m2 were not inhibited, compared with those collected immediately before therapy. Relatively high levels of exposure to CDDP are required for inhibition of the generation of new cytotoxic effectors, most likely because of its antiproliferative effect. These results may bear relevance to approaches involving the combined use of CDDP and IL-2-LAK. 相似文献
52.
53.
Long, interlaminar, astroglial processes and its patterned organization in the striate cortex of adult primates was previously described. Loss of visual input following bilateral retinal detachment and degeneration in an adult Cebus apella monkey resulted three months later in reduction of interlaminar processes immunoreactive to Glial Fibrillary Acid Protein antibody, loss of the honeycomb-like pattern normally present in tangential sections, and loss of high density patches of terminal segments of those processes in the opercular striate. These results further indicate the highly interactive nature of neuron-glial cerebral cortex architecture, and the dynamic regulation of astroglial interlaminar processes. 相似文献
54.
Astrocytes were cultured from striatum and neocortex of fetal (embryonic day 90) monkeys (Cebus apella). The cultures grew well, and the cells retained viability after freeze-storage and thawing. The cells displayed depolarized membrane potentials (-19 and -33 mV, for striatal and cortical cells, respectively) and the vast majority of cells were dye-coupled to a mean of 7 (1-18) neighbouring cells. Cell coupling was blocked by octanol (0.25 and 0.5 mM) but was independent of high K+ (10 and 50 mM) and glutamate (500 microm). Thus, cultures of fetal primate astrocytic cells are established as a model system for studies on astroglial cell-cell coupling. 相似文献
55.
R Ciccocioppo S Angeletti G Colombo G Gessa M Massi 《European journal of pharmacology》1999,373(1):13-19
The density of 5-HT2A binding sites in the brain of Sardinian alcohol-preferring (sP) and nonpreferring (sNP) rats was evaluated, using [3H]ketanserin for quantitative autoradiography. The highest [3H]ketanserin binding levels were found in the anterior olfactory nucleus, prefrontal cortex, medial prefrontal cortex, post-genual anterior cingulate cortex, insular cortex and claustrum. Statistically significant differences between sP and sNP rats were found in prefrontal cortex, medial prefrontal cortex and post-genual anterior cingulate cortex, where sP rats showed about 20% lower [3H]ketanserin binding levels. No significant difference was found in other areas, although some of them showed slightly lower [3H]ketanserin binding density in sP rats. The 5-HT2A receptor agonist, (+/-)-1-(2,5-dimethoxy-4-iodophenyl)-2-amino-propane hydrochloride (DOI), microinjected into the medial prefrontal cortex, induced a lower number of wet dog shakes in sP than in sNP rats. These results indicate a different density of 5-HT2A binding sites, and a different functional regulation of 5-HT2A receptor mechanisms in discrete brain areas of sP, in comparison to sNP rats. These findings, and those showing lower levels of 5-HT in the frontal cortex of sP rats, suggest that altered 5-HT function in fronto-cortical areas could be linked to the genetic predisposition to high voluntary ethanol intake in these rats. 相似文献
56.
Marzola M.; Parma G.; Bonazzi C.; Colombo N.; Maneo A.; Pittelli M. R.; Mangioni C. 《Annals of oncology》1996,7(4):419-421
OBJECTIVE:: To evaluate the anti-tumour activity and toxicity of ifosfamide(5 g/m2 continuous infusion) and mitoxantrone (10 mg/ m2 givenin combination every 3 weeks in patients with ovarian cancerresistant to at least two previous regimens which included platinum. PATIENTS AND METHODS:: Additional eligibility criteria were an ECOG performance status2 and measurable disease. Of 47 patients entered in the study,8 were defined as platinum-resistant and 39 as potentially sensitiveaccording to Markman's criteria. Thirty-five patients had alsoreceived pacitaxel as last treatment before entering this study.Tumour response was evaluated every three cycles. RESULTS:: One complete and 11 partial responses were reported, for anoverall response rate of 25% (95% CI: 14%40%). Threeof the partial responders were resistant to num. None of the7 partial responders pretreated with had responded to it. Theoverall median urvival was months. Neutropema G4 was reportedin 18 patients(42%) with hospitalisation because of febrileneutropenia in 3 of them. CONCLUSIONS:: In patients with ovarian cancer failing least 2 previous therapiesincluding platinum, the nation of ifosfamide and mitoxantronehas shown antitumour activity comparable to that of paclitaxel,with accept able toxicity. Objective responses were reportedalso patients failing pacitaxel, suggesting a lack of crossresistance. ifosfamide, mitoxantrone, ovarian cancer 相似文献
57.
AIMS AND BACKGROUND: Isolated vaginal recurrences of endometrial carcinoma are rare, and prognostic factors that predict treatment outcome are still not well defined. The aim of the present study was to evaluate the results of brachytherapy in isolated vaginal recurrences from endometrial carcinoma. METHODS: Thirty-five patients with isolated vaginal recurrences were treated with brachytherapy with intravaginal ovoids or cylinders that were calculated to deliver 6000 to 7000 cGy at the surface. Patients were assessed for size and location of recurrence at presentation, response and complications from therapy. RESULTS: Treatment was well tolerated by most patients. Grade 2 toxicity occurred in 4 patients (3 cases of partial vaginal stenosis and one proctitis). Complete response to radiation was observed in all patients, and an overall 9 failures were observed (4 local, 4 distant and 1 local plus distant). Twenty patients (57%) were alive without evidence of disease at 3 to 11 years following treatment. Site of vaginal recurrence (upper third versus others) and long (more than 12 months versus less than 12 months) interval from hysterectomy were the only factors significantly related to local failures. CONCLUSIONS: Isolated vaginal recurrences following hysterectomy for endometrial carcinoma can be treated with brachytherapy with a low rate of severe toxicity. 相似文献
58.
Franco M. Muggia Kenneth K. Chan Christy Russell Nicoletta Colombo James L. Speyer Kishore Sehgal Susan Jeffers Joan Sorich Lawrence Leichman Uziel Beller E. Mark Beckman 《Cancer chemotherapy and pharmacology》1991,28(4):241-250
Summary Intraperitoneal (i.p.) 5-fluoro-2-deoxyuridine (Floxuridine, FUdR, FdUrd) was evaluated in a phase I study at a starting level of 500 mg given on 1 day in 2 I 1.5% dialysate. Escalations within patients were allowed every other cycle. A total of 23 patients (age, 32–78 years) received 108 treatment courses. Local tolerance at all dose levels was excellent, with no cases of drug-related peritonitis being observed. Nausea and vomiting increased in severity in relation to dose and was universal at >3,000 mg ×3 days. One patient each developed grade 1 mucositis as well as diarrhea at a dose of 3,000 mg×3 days and leukopenia and thrombocytopenia at 5,000 mg×3 days. Peritoneal fluid (PF) and plasma (PL) FdUrd profiles were monitored by an HPLC method in 13 subjects, with 7 being studied serially at 2–4 increment doses for up to 6 h. Profiles that exhibited apparent linear pharmacokinetics gave PF drug levels 2–4 logs higher than the PL counterparts, with the latter essentially declining in parallel to the former, indicating that the disposition of FdUrd from the peritoneal compartment is rate-determining. The mean terminal half-life for PF FdUrd was found to be 115 min and mean peritoneal clearance was 25 ml/min. The vast differences in drug levels and AUC found between the PF and the PL profiles suggests a high systemic clearance of FdUrd, which was confirmed in two patients receiving 2 g FdUrd by short i.v. infusion. A disproportionate increase in the plasma FdUrd levels and the corresponding AUC values was found with increasing dose, suggesting a disproportionate increase in the systemic partitioning of FdUrd when doses were escalated within a patient. Substantial levels of peritoneal 5-fluorouracil (FUra) were also detected in most of the subjects. Thus, FdUrd was found to have several desirable properties for i.p. administration: (1) a 2- to 4-log pharmacologic advantage, (2) the absence of local toxicities, and (3) a favorable antitumor spectrum and some evidence of antitumor effects in this phase I and pharmacology study. A 3,000-mg dose given in 2 l 1.5% dialysate for 3 consecutive days exhibited antitumor activity and produced no systemic toxicity except nausea and vomiting, which was controlled by antiemetics. This dose schedule is therefore recommended for phase II trials directed against small-volume disease in the peritoneal cavity, such as may be found in some stages of ovarian and gastrointestinal cancers. In addition, it is suitable for further exploration as a part of regimens including systemic therapy or drugs that modulate the action of fluoropyrimidines.Supported in part by Cancer Center Core Grant CA 14089, by ROI CA 50 412, by an ACS Institutional Grant (IN21Z, to C. R.) and by the Italian-American Foundation award (to N. C.)Deceased 相似文献
59.
The synchronous performance of aortic graft with a second surgical procedure should be avoided because of the risk of subsequent graft infection. The Authors reported the experience of 21 patients who underwent synchronous aortic graft with second surgical procedure. No graft infection occurred and it is concluded that such combined operation may be safer to perform than staged surgery in elderly patients. 相似文献
60.
Colombo T Wieselmann G Pichler-Zalaudek K Steinbrenner B Jantscher M Halbwedl I Zapotoczky HG Hubmer G 《Der Urologe. Ausg. A》2000,39(2):160-165
PURPOSE: The pontine micturition center plays a central role in regulating the micturition reflex, but the precise neural mechanisms are unclear. The cerebral cortex is involved in coordinating micturition but there is little knowledge on specific evolutionary higher brain regions. The present study aimed to investigate whether cortical activation during micturition can be demonstrated by EEG power spectra patterns and to explore whether specific cortical regions involved in the interaction of inhibition and release during the micturition reflex can be discerned. We also aimed to test whether intravesical electrostimulation (IVES) therapy in patients with micturition disorders has an effect on patterns of cortical activity. METHODS: The healthy control group was divided into those who were able to void when requested (6 women, 12 men) and those who were not (8 women, 10 men). These subgroups were compared separately with the 14 patients before and after IVES for voiding dysfunction. Following IVES all patients were able to void spontaneously. Mean age of the patients and healthy volunteers was 52 and 30 years, respectively. At the beginning of the study all subjects had a bladder volume of approximately 250 mL as measured by sonography. The EEG was obtained at rest and during the attempt to void. In the patients' group EEG was obtained before IVES treatment and at the day of the last stimulation. The measurement period lasted about 6 minutes. At the beginning of the recording the proband was asked to close his/her eyes. During the resting period after 1 minute the patient was asked to open his/her eyes. After 10 seconds he/she was asked to close his/her eyes again. Then, with eyes still closed, the patient was asked to void. During the entire EEG recording the patient was seated in a comfortable, electrically isolated chair in a darkened room and separated from the examiner by a partition. The subject was asked to relax and not move his/her eyes. The EEG was recorded from the 19 standard points (10-20 System) versus an averaged mastoid electrode with a gold-plated cup electrode (Glass). An EOG was recorded simultaneously to register eye artefacts. The amplification chain was calibrated with a 10-Hz 100-microVss sinus signal generated with a biosignal amplifier. The transitional resistances of all EEG channels were less than 5 kOhm and established as soon as possible. EEG and EOG signals were amplified and recorded with a B.E.S.T. Brain Mapping System. The recording frequency was 256 Hz and the resolution of the analog digital conversion was 12 bit. A high pass and a low pass filter were set to 0.53 Hz and 70 Hz, respectively. All recordings were inspected visually before computer analysis. Artefacts were marked and excluded from the further analysis. None of the EEG recordings showed clinical abnormalities. As expected, the EEGs during voiding attempts showed some muscle potentials and slow motion artefacts. For each subject two artefact-free resting segments of about 20 seconds, one from the resting phase and one from the voiding attempt, were defined by hand for automated analysis. Relative power spectra (microV2) were calculated for the defined segments. From the spectra the relative alpha band power (7.5-13.0 Hz) was calculated for each subject for rest and voiding. Group (patients vs. voiding probands vs. probands unable to void) and sex were independent variables. The alpha power of the 17 electrode positions of the 10-20 system (without Fp1 and Fp2) during rest and attempted voiding were repeated measurement variables. The frontopolar electrode was not used because of its susceptibility to artefacts. The number of dependent variables was due to the explorative nature of the study. With interactions of variables with more than two factor levels a Greenhouse-Geisser correction was performed. Interactions were subjected to contrast analysis and Newman-Keuls-Post tests. RESULTS: Significant effects were seen for BEDINGUNG ( 相似文献