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51.
52.
The involvement of adenosine A(1) and A(2A) receptors in the motor effects of caffeine is still a matter of debate. In the present study, counteraction of the motor-depressant effects of the selective A(1) receptor agonist CPA and the A(2A) receptor agonist CGS 21680 by caffeine, the selective A(1) receptor antagonist CPT, and the A(2A) receptor antagonist MSX-3 was compared. CPT and MSX-3 produced motor activation at the same doses that selectively counteracted motor depression induced by CPA and CGS 21680, respectively. Caffeine also counteracted motor depression induced by CPA and CGS 21680 at doses that produced motor activation. However, caffeine was less effective than CPT at counteracting CPA and even less effective than MSX-3 at counteracting CGS 21680. On the other hand, when administered alone in habituated animals, caffeine produced stronger motor activation than CPT or MSX-3. An additive effect on motor activation was obtained when CPT and MSX-3 were coadministered. Altogether, these results suggest that the motor-activating effects of acutely administered caffeine in rats involve the central blockade of both A(1) and A(2A) receptors. Chronic exposure to caffeine in the drinking water (1.0 mg/ml) resulted in tolerance to the motor effects of an acute administration of caffeine, lack of tolerance to amphetamine, apparent tolerance to MSX-3 (shift to the left of its 'bell-shaped' dose-response curve), and true cross-tolerance to CPT. The present results suggest that development of tolerance to the effects of A(1) receptor blockade might be mostly responsible for the tolerance to the motor-activating effects of caffeine and that the residual motor-activating effects of caffeine in tolerant individuals might be mostly because of A(2A) receptor blockade.  相似文献   
53.
PURPOSE: The extent of venous thromboembolism (VTE) associated with central vein catheters (CVC) in cancer patients remains unclear. The aim of this study was to evaluate the efficacy and safety of the low molecular weight heparin, enoxaparin, in the prevention of VTE. PATIENTS AND METHODS: In a multicenter, double-blind study, consecutive cancer patients scheduled for CVC insertion were randomly assigned to receive either subcutaneous enoxaparin 40 mg once a day or placebo. Treatment was started 2 hours before CVC insertion and continued for 6 weeks. The primary end points of the study were deep vein thrombosis (DVT), confirmed by venography of the CVC limb performed 6 weeks after randomization, or clinically overt pulmonary embolism, confirmed by objective testing during the study drug administration. Patients were assessed for bleeding complications. RESULTS: Three hundred eighty-five patients were randomized, of which 321 (83.4%) underwent venography. A venography was adequate for adjudication in 155 patients in each treatment group. A DVT was observed in 22 patients (14.1%) treated with enoxaparin and in 28 patients (18.0%) treated with placebo, corresponding to a relative risk of 0.78 (95% CI, 0.47 to 1.31). No major bleeding occurred. Five patients (2.6%) in the enoxaparin group and two patients (1.0%) in the placebo group died during the treatment period. CONCLUSION: In this study, no difference in the rate of CVC-related VTE was detected between patients receiving enoxaparin and patients receiving placebo. The dose of enoxaparin used in this study proved to be safe. Clinical trials evaluating higher enoxaparin doses could optimize the efficacy of this agent for this indication.  相似文献   
54.
PURPOSE: Bcl-2 overexpression is frequently detected in lymphoid malignancies, being associated with poor prognosis and reduced response to therapy. Here, we evaluated whether Bcl-2 overexpression affects the cytotoxic activity of proteasome inhibitors taken alone or in association with conventional anticancer drugs or tumor necrosis factor-related apoptosis-inducing ligand (TRAIL). EXPERIMENTAL DESIGN: Jurkat cells engineered to overexpress Bcl-2 were treated with proteasome inhibitors (MG132, epoxomicin, and bortezomib), anticancer drugs (etoposide and doxorubicin), TRAIL, or combinations of these compounds. Cell death and loss of mitochondrial transmembrane potential were detected by flow cytometry. Cytosolic relocalization of cytochrome c and SMAC/Diablo, caspase cleavage, and Bcl-2 and Mcl-1 levels were determined by immunoblotting. Nuclear factor-kappaB inhibition was done by retroviral transduction with a dominant-negative mutant of IkappaBalpha. RESULTS: Bcl-2 overexpression results in significant inhibition of apoptosis in response to proteasome inhibitors, antiblastics, and TRAIL. Addition of TRAIL to proteasome inhibitors results in a synergistic cytotoxic effect in Bcl-2-overexpressing cells, whereas this result is not reproduced by the combination of proteasome inhibitors with antiblastic drugs. Importantly, proteasome inhibitors plus TRAIL induce mitochondrial dysfunction irrespective of up-regulated Bcl-2. Bcl-2 cleavage to a fragment with putative proapoptotic activity and elimination of antiapoptotic Mcl-1 may both play a role in proteasome inhibitors-TRAIL cooperation. Conversely, nuclear factor-kappaB inhibition by proteasome inhibitors is per se insufficient to explain the observed synergy. CONCLUSIONS: Combined proteasome inhibitors and TRAIL overcome the apoptotic threshold raised by Bcl-2 and may prove useful in the treatment of chemoresistant malignancies with up-regulated Bcl-2.  相似文献   
55.
Chest tubes are routinely inserted after thoracic surgery procedures in different sizes and numbers. The aim of this study is to assess the efficacy of Smart Drain Coaxial drainage compared with two standard chest tubes in patients undergoing thoracotomy for pulmonary lobectomy. Ninety-eight patients (57 males and 41 females, mean age 68.3 ± 7.4 years) with lung cancer undergoing open pulmonary lobectomy were randomized in two groups: 50 received one upper 28-Fr and one lower 32-Fr standard chest tube (ST group) and 48 received one 28-Fr Smart Drain Coaxial tube (SDC group). Hospitalization, quantity of fluid output, air leaks, radiograph findings, pain control and costs were assessed. SDC group showed shorter hospitalization (7.3 vs. 6.1 days, p = 0.02), lower pain in postoperative day-1 (p = 0.02) and a lower use of analgesic drugs (p = 0.04). Pleural effusion drainage was lower in SDC group in the first postoperative day (median 400.0 ± 200.0 mL vs. 450.0 ± 193.8 mL, p = 0.04) and as a mean of first three PODs (median 325.0 ± 137.5 mL vs. 362.5 ± 96.7 mL, p = 0.01). No difference in terms of fluid retention, residual pleural space, subcutaneous emphysema and complications after chest tubes removal was found. In conclusion, Smart Drain Coaxial chest tube seems a feasible option after thoracotomy for pulmonary lobectomy. The SDC group showed a shorter hospitalization and decreased analgesic drugs use and, thus, a reduction of costs.  相似文献   
56.
Antioxidant properties of ursodeoxycholic acid   总被引:5,自引:0,他引:5  
We have investigated potential antioxidant properties of the clinically relevant bile acid UDCA, which reaches therapeutic concentrations up to 0.09 and 29 mM, respectively, in human plasma and bile. UDCA was an excellent scavenger of OHz.rad; generated by FeCl(3)-EDTA, H(2)O(2) and ascorbate in the deoxyribose oxidation test, showing IC(min) and IC(50) values of 0.02 and 0.2 mM, respectively, and a second-order rate constant for reaction with OHz.rad; of 2+/-0.1 x 10(10)M(-1)s(-1). Notably, the drug could enhance at 1.5 mM concentration the antioxidant capacity of human bile against OHz.rad;-induced deoxyribose oxidation. UDCA also showed antioxidant effects in the deoxyribose test performed with nonchelated iron ions, such as Fe(2+) plus H(2)O(2) (IC(min): 7 mM, IC(50): 20 mM) or Fe(3+) plus H(2)O(2) and ascorbate (IC(min): 0.3 mM, IC(50): 5 mM), and inhibited ferrozine-Fe(2+) and desferrioxamine-Fe(3+) complexes formation with IC(50) values of, respectively, 12 and 0.3 mM, indicating that the drug interacts more with iron(III) than with iron(II). Moreover, UDCA significantly inhibited phospholipid liposome peroxidation induced by the OHz.rad;-generating system FeCl(3)-EDTA, H(2)O(2) and ascorbate (IC(min): 0.75 mM, IC(50): 3 mM), and by peroxyl radicals generated in the aqueous phase by AAPH (IC(min): 8 mM, IC(50): 14 mM). UDCA, even at 25 mM concentration, was ineffective on the lipoperoxidation mediated by Fe(2+) alone, but at the same concentration counteracted significantly that by Fe(3+) plus ascorbate, further pointing to its preferential antioxidant interaction with iron(III).In conclusion, UDCA has direct antioxidant properties, which are especially relevant against Fe(3+)- and OHz.rad;-dependent biomolecular oxidative damage; such properties are evident at therapeutically relevant drug concentrations, suggesting that UDCA could act as an antioxidant in vivo.  相似文献   
57.
Most of the copper sulfide synthetic approaches developed until now are still facing issues in their procedure, such as long synthesis duration, high energetic consumption, and high implementation costs. This publication reports a facile and sustainable approach for synthesizing copper sulfides on a large scale. In particular, an industrial by-product of sulfur waste was used as a sulfurizing agent for copper sulfide synthesis in a water medium. The reaction was performed in the hydrothermal environment by following a novel proposed mechanism of copper sulfide formation. The investigation of morphological and optical properties revealed that the target products obtained by using waste possess the resembling properties as the ones synthesized from the most conventional sulfurizing agent. Since the determined band gap of synthesis products varied from 1.72 to 1.81 eV, the photocatalytic properties, triggered under visible light irradiation, were also investigated by degrading the methylene blue as a model pollutant. Importantly, the degradation efficiency of the copper sulfide synthesized from sulfur waste was equivalent to a sample obtained from a reference sulfurizing agent since the value for both samples was 96% in 180 min. This very simple synthetic approach opens up a new way for large-scale sustainable production of visible-light-driven photocatalysts for water purification from organic pollutants.  相似文献   
58.
CoronaVirus disease-2019 has changed the delivery of health care worldwide and the pandemic has challenged oncologists to reorganize cancer care. Recently, progress has been made in the field of precision medicine to provide to patients with cancer the best therapeutic choice for their individual needs. In this context, the Foundation Medicine (FMI)-Liquid@Home project has emerged as a key weapon to deal with the new pandemic situation. FoundationOne Liquid Assay (F1L) is a next-generation sequences-based liquid biopsy service, able to detect 324 molecular alterations and genomic signatures, from May 2020 available at patients’ home (FMI-Liquid@Home). We analyzed time and costs saving for patients with cancer, their caregivers and National Healthcare System (NHS) with FMI-Liquid@Home versus F1L performed at our Department. Different variables have been evaluated. Between May 2020 and August 2021, 218 FMI-Liquid@Home were performed for patients with cancer in Italy. Among these, our Department performed 153 FMI-Liquid@Home with the success rate of 98% (vs. 95% for F1L in the hospital). Time saving for patients and their caregivers was 494.86 and 427.36 hours, respectively, and costs saving was 13 548.70€. Moreover, for working people these savings were 1084.71 hours and 31 239.65€, respectively. In addition, the total gain for the hospital was 163.5 hours and 6785€, whereas for NHS was 1084.71 hours and 51 573.60€, respectively. FMI-Liquid@Home service appears to be useful and convenient allowing time and costs saving for patients, caregivers, and NHS. Born during the COVID-19 pandemic, it could be integrated in oncological daily routine in the future. Therefore, additional studies are needed to better understand the overall gain and how to integrate this service in different countries.  相似文献   
59.
A meta-analysis of four trials showed significant advantage in pregnancy and delivery rates with aromatase inhibitors compared with CC in women with PCOS. A recent randomized trial demonstrated no clear benefit.  相似文献   
60.
Treatment of unexplained infertility is empiric and different regimens or protocols have been used so far. Clomiphene can be used alone or combined with gonadotrophins. Aromatase inhibitors may offer an alternative for first-line treatment. To compare the efficacy of aromatase inhibitors versus climiphene, we conducted a systematic review and meta-analysis for randomized controlled trials comparing the above regimens to estimate live pregnancy rates in women with unexplained infertility. Trials were located through PubMed and Cochrane Library searches. Methodological quality of included trials has been assessed. Then, 2 x 2 tables were constructed, and pooled odds ratios (ORs) were calculated. Ten arms (273 patients) were included in the meta-analysis. ORs were homogeneous between studies (heterogeneity chi2 = 2.33, P = 0.676). No difference was observed for live pregnancies (pooled OR 0.87, 95% CI, 0.46-1.65, P = 0.666) for aromatase inhibitors versus clomiphene citrate; however, the definition of live pregnancy by the authors was clear only in one trial. Data regarding secondary outcomes were omitted, and methodogical quality of eligible trials did not reach high scores. Evidence from randomized data regarding the use of aromatase inhibitors is fragmented and weak. Aromatase inhibitors may have a role in the treatment of women with unexplained infertility desiring pregnancy. However, meticulous reporting and study design should be a priority in this field and large, registered, and properly designed randomized trials are essential to test whether aromatase inhibitors can be introduced as a first-line treatment in carefully selected subgroups of women with unexplained infertility.  相似文献   
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