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1.
Nitric oxide (NO), a biologically active mediator generated in many cell types by the enzyme NO synthase, may play an important role in cardiovascular toxicity that is frequently observed in cancer patients during intravenous (i.v.) interleukin 2 (IL-2) therapy. The induction of NO synthase and the production of NO seem to be involved in the pathogenesis of the vascular leakage syndrome, as well as in the regulation of myocardial contractility. In the present study, we evaluated the pattern of plasmatic NO changes during multiple cycles of continuous i.v. infusion (CIVI) of IL-2 in ten advanced cancer patients (five males, five females, median age 59 years, range 33-67 years; eight affected by renal cell cancer and two affected by malignant melanoma). The patients received IL-2 at 18 MIU m-2 day-1 (14 cycles) or 9 MIU m-2 day-1 (seven cycles) for 96 h, repeated every 3 weeks. Interferon alpha (IFN alpha) was also administered subcutaneously (s.c) during the 3 week interval between IL-2 cycles. For each cycle, plasma samples were collected before treatment (t0), 24 h (t1), 48 h (t2), 72 h (t3) and 96 h (t4) after the start of IL-2 infusion, and 24 h after the end of the cycle. NO concentration was determined spectrophotometrically by measuring the accumulation of both nitrite and nitrate (after reduction to nitrite). The following observations may be drawn from data analysis: (1) plasma nitrate + nitrite significantly raised during treatment (P = 0.0226 for t0 vs t3), but statistical significance was retained only when cycles administered with IL-2 18 MIU m-2 day-1 are considered (P = 0.0329 for t0 vs t3; P = 0.0354 for t0 vs t2 vs t4) (dose-dependent pattern); (2) during subsequent cycles a significant trend toward a progressive increase of plasma nitrate + nitrite levels, with increasing cumulative dose of IL-2, was observed (linear regression coefficient r = 0.62, P = 0.0141 for t0; r = 0.80, P = 0.0003 for t1; r = 0.62, P = 0.013 for t2; r = 0.69, P = 0.045 for t3); (3) plasma nitrate + nitrite levels peaked earlier in subsequent cycles than in the first cycle; (4) all patients experienced hypotension. The mean of the systolic blood pressure values was significantly lower at the time of plasma nitrate + nitrite peak than at t0 (P = 0.0004); (5) the two cases of grade III hypotension occurred in patients with the higher mean and peak plasma nitrate + nitrite values. We conclude that determination of plasma nitrate + nitrite levels during CIVI IL-2 can usefully estimate, in a dose-dependent pattern, the degree of peripheral vascular relaxation and capillary leakage associated with cytokine action, clinically manifested as hypotension. However, isolated cardiac toxicity that continues to represent a relevant problem during IL-2 therapy, does not appear to correlate with plasma nitrate + nitrite levels; therefore, further studies are required to understand adequately the mechanisms underlying IL-2-induced cardiac toxicity.  相似文献   
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Cuff pressure of endotracheal tubes increases to dangerous levels during anesthesia with nitrous oxide. In a small clinical study the Authors conclude that Mallinckrodt-Brandt endotracheal tubes are the only "low pressure" tubes available at the moment.  相似文献   
4.
In isolated, perfused mesenteric vascular beds from female rats, it was assessed whether the constrictor response to cirazoline, an alpha(1)-adrenergic agonist, or acetylcholine (ACh)-induced relaxation was altered by oestrous cycle or pregnancy and the ability of nitric oxide (NO), prostanoids and endothelium-derived hyperpolarizing factor (EDHF) to modulate these responses. Mesenteries, removed from female rats on each oestrous cycle day and gestation day 16, were perfused with physiological salt solution. Tone was induced with cirazoline (1 micromol/l), and concentration-response curves to ACh generated. Responsiveness to ACh was tested in the presence of N(omega)-nitro-L-arginine (L-NA), ibuprofen (IBU) and tetrabutylammonium (TBA), to inhibit nitric oxide synthase (NOS), cyclo-oxygenase and K(+) channels respectively. Cirazoline-induced tone was smaller in pro-oestrous and pregnant groups, but the increase in tone to L-NA was larger in pregnant compared with oestrous and dioestrous groups. Control responses to ACh were not different, but L-NA attenuated the response in virgin groups only. IBU did not affect the ACh response, but TBA attenuated it in all groups. When TBA was introduced first, ACh-induced dilatation was significantly reduced and not altered by L-NA addition. These results suggest that in the mesenteric vascular bed from cycling and pregnant rats, EDHF is the major mediator of ACh-induced dilatation and NOS may be up-regulated in pregnant and pro-oestrous rats.  相似文献   
5.
ObjectivesTo evaluate the utility of in-bore multiparametric magnetic resonance-guided biopsy of the prostate (IB) in patients with visible lesion/s and previous negative software-based multiparametric magnetic resonance imaging/ultrasonography fusion-targeted biopsy of the prostate (FTB).Patients and methodsWe retrospectively analysed prospectively maintained database including consecutive men undergoing IB from March 2013 to October 2017 in 2 European centres expert in this procedure. We selected men with the following criteria: No previous treatment for prostate cancer (CaP), multiparametric magnetic resonance imaging (mpMRI) lesion(s) PIRADS score ≥ 3, FTB showing no clinically significant cancer (csCaP), and subsequent IB. Patient's characteristics, mpMRI findings, biopsy technique, and histopathological results were extracted. The primary outcome was to determine the detection rate of csCaP, defined as any Gleason pattern ≥ 4. A multivariable analysis was performed to identify predictors of positive findings at IB.ResultsFifty-three men were included. Median age was 68 years (interquartile range [IQR] 64–68), median Prostate-Specific Antigen (PSA) was 7.6 ng/ml (IQR 5.2–10.9), and median prostate volume was 59 ml (IQR 44–84). Fifty-six lesions with PIRADS score 3 in 9 cases (16%), 4 in 30 cases (54%), and 5 in 17 cases (30%) were detected. FTB was performed in all cases using a transrectal approach with 3 different platforms (Toshiba, Koelis, and Artemis). Median time between FTB and IB was 3 months (IQR 1–7). A median of 2 cores per lesion were collected with IB (IQR 2–3). No cancer, clinically insignificant and clinically significant cancer were found in 33 (59%), 9 (16%), and 14 (25%) targeted lesions, respectively. Median maximum cancer core length and maximum positive percentage were 9 mm (3–13) and 55% (21%–80%). The only predictor of csCaP on IB was prostate volume (P = 0.026) with an ideal cut-off at 70 ml.ConclusionOne in 4 patients with previous negative FTB, IB was able to detect csCaP. According to this study, IB would be of particularly useful in patients with large glands.  相似文献   
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PURPOSE: We demonstrated that vaccination with irradiated tumor cells engineered to secrete granulocyte-macrophage colony-stimulating factor (GM-CSF) stimulates potent, specific, and long-lasting antitumor immunity in multiple murine models and patients with metastatic melanoma. To test whether this vaccination strategy enhances antitumor immunity in patients with metastatic non-small-cell lung cancer (NSCLC), we conducted a phase I clinical trial. PATIENTS AND METHODS: Resected metastases were processed to single-cell suspension, infected with a replication-defective adenoviral vector encoding GM-CSF, irradiated, and cryopreserved. Individual vaccines consisted of 1 x 10(6), 4 x 10(6), or 1 x 10(7) cells, depending on overall yield, and were administered intradermally and subcutaneously at weekly and biweekly intervals. RESULTS: Vaccines were successfully manufactured for 34 (97%) of 35 patients. The average GM-CSF secretion was 513 ng/10(6) cells/24 h. Toxicities were restricted to grade 1 to 2 local skin reactions. Nine patients were withdrawn early because of rapid disease progression. Vaccination elicited dendritic cell, macrophage, granulocyte, and lymphocyte infiltrates in 18 of 25 assessable patients. Immunization stimulated the development of delayed-type hypersensitivity reactions to irradiated, dissociated, autologous, nontransfected tumor cells in 18 of 22 patients. Metastatic lesions resected after vaccination showed T lymphocyte and plasma cell infiltrates with tumor necrosis in three of six patients. Two patients surgically rendered as having no evidence of disease at enrollment remain free of disease at 43 and 42 months. Five patients showed stable disease durations of 33, 19, 12, 10, and 3 months. One mixed response was observed. CONCLUSION: Vaccination with irradiated autologous NSCLC cells engineered to secrete GM-CSF enhances antitumor immunity in some patients with metastatic NSCLC.  相似文献   
7.
The clinical usefulness of total sleep deprivation (TSD) in the treatment of bipolar depression is hampered by a high-rate short-term relapse. Previous literature has suggested that both long-term lithium treatment and light therapy could successfully prevent relapse. We randomized 115 bipolar depressed inpatients to receive three cycles of TSD, alone or in combination with morning light exposure, given at an intensity of 150 or 2500 lux. Forty-nine patients were undergoing long-term treatment with lithium salts (at least 6 months), while 66 patients were taking no psychotropic medication. Mood was self-rated by the Visual Analogue Scale three times a day during treatment. The results showed that both light therapy and ongoing lithium treatment significantly enhanced the effects of TSD on the perceived mood, with no additional benefit when the two treatments were combined. Subjective sleepiness during TSD, as rated by the self-administered Stanford Sleepiness Scale, was significantly reduced by light exposure, and was correlated with the outcome. This study confirms the possibility of obtaining a sustained antidepressant response to TSD in bipolar patients.  相似文献   
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Not only workers employed at industrial plants are exposed to intoxication with the element they manipulate, the population at large is also at risk of suffering health problems caused by contaminating wastes inadequately treated for their safe disposal. As a result certain toxic substances, such as hexavalent chromium,has reached the general population including children. The present study sought to evaluate the effect of intoxication with hexavalent chromium on body and mandibular growth and tooth eruption in suckling Wistar rats. Potassium dichromate was administered by gavage in a dose of 6.25 or 12.5 mg/kg body weight (b.w.) to one of the two groups of 4-day-old Wistar rats during 10 days. Our results showed that the effects of chromium are dose-dependent. Morphometric studies of body growth showed lower body weight in both experimental groups and shorter tail length in animals receiving 12.5 mg/kg b.w. dose of chromium, compared with controls. All parameters of mandibular growth were lower in the experimental group receiving 12.5 mg/kg b.w. of chromium. Differences in tooth eruption were observed at the level of the first molar in animals receiving 12.5 mg/kg and of the second molar in those receiving 6.25 mg/kg b.w. of chromium. Chromium was found to affect all the studied parameters.  相似文献   
10.
Shattil  SJ; Motulsky  HJ; Insel  PA; Flaherty  L; Brass  LF 《Blood》1986,68(6):1224-1231
Epinephrine causes platelet aggregation and secretion by interacting with alpha 2-adrenergic receptors on the platelet surface. Platelet aggregation requires the binding of fibrinogen to a specific receptor on the membrane glycoprotein IIb-IIIa complex. Although the IIb-IIIa complex is identifiable on the surface of resting platelets, the fibrinogen receptor is expressed only after platelet activation. The current studies were designed to examine the effect of occupancy of platelet alpha 2-adrenergic receptors by epinephrine on the expression of fibrinogen receptors and on the aggregation of platelets. The ability of epinephrine to induce the expression of fibrinogen receptors was studied under two different conditions: acute stimulation (less than 1 min) and prolonged stimulation (50 to 90 min), the latter of which is associated with a reduction or "desensitization" of the platelet aggregation response. Expression of the fibrinogen receptor was monitored with 125I-fibrinogen as well as with 125I-PAC-1 (PAC-1), a monoclonal antibody that binds to the glycoprotein IIb-IIIa complex only after platelets are activated. Epinephrine caused an immediate increase in PAC-1 and fibrinogen binding that was dependent on occupancy of the alpha 2-receptor by epinephrine and on the presence of extracellular free Ca (KCa = 30 mumol/L). By itself, 1 mmol/L Mg was unable to support induction of the fibrinogen receptor by epinephrine. However, it did decrease the Ca requirement by about two orders of magnitude. Prolonged stimulation of unstirred platelets by epinephrine led to a 70% decrease in the aggregation response when the platelets were subsequently stirred. Despite their decreased aggregation response, desensitized platelets bound PAC-1 and fibrinogen normally, indicating that the loss of aggregation was not due simply to a decrease in fibrinogen receptor expression. Although desensitization was not affected by pretreatment of the platelets with aspirin, it was partially prevented when extracellular Ca was chelated by EDTA during the long incubation with epinephrine. These studies demonstrate that once platelet alpha 2-adrenergic receptors are occupied by epinephrine, extracellular Ca is involved in initiating the aggregation response by supporting the induction of the fibrinogen receptor and the binding of fibrinogen. Furthermore. Ca-dependent reactions subsequent to fibrinogen binding may be necessary for maximal platelet aggregation and are impaired when platelets become desensitized to epinephrine.  相似文献   
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