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971.
The capacity to generate effective dendritic cells (DC) from adult acute lymphoblastic leukemia (ALL) patients in complete remission (CR) and off-therapy was investigated. Monocyte-derived DC cultured in the presence of granulocyte-macrophage colony-stimulating factor, interleukin (IL)-4 and tumor necrosis factor (TNF)-alpha expressed maturation markers, produced IL-12 and loaded apoptotic bodies to a similar extent to normal DC. Patients' circulating T and NK lymphocytes were normally represented and, after stimulation, were capable of producing TNF-alpha and interferon-gamma to a similar extent to control lymphocytes. DC loaded with leukemia-derived apoptotic bodies increased their ability to stimulate both allogeneic and autologous lymphocytes, and to generate specific anti-leukemic CD3 + cells. These findings offer a rationale for the design of DC-based vaccine programs for adult ALL patients in CR with the aim of controlling/eradicating the disease.  相似文献   
972.
Little controlled drug administration data are available to aid in the interpretation of gamma-hydroxybutyric acid (GHB) distribution in conventional and nonconventional fluids and the potential correlation between the pharmacokinetics of GHB and drug effects. Single oral sodium GHB doses of 50 mg/kg were administered to five volunteers. Plasma, oral fluid, urine, and sweat were analyzed for GHB by gas chromatography-mass spectrometry. GHB stability in plasma was studied at different storage temperatures. Subjective effects were measured using a set of 13 different visual analog scales. Mean peak GHB plasma concentrations at 30 minutes were 83.1 microg/mL. After the absorption phase, concentrations declined to mean values of 0.9 microg/mL at 6 hours. GHB was found in oral fluid at peak value concentrations equivalent to one third to one fourth of those found in plasma. The oral fluid-to-plasma ratio varied two fold in the 1- to 6-hour time range but always was lower than unit. The mean half-life (t1/2) of GHB was approximately 0.7 hour in plasma and approximately 1.2 hours in oral fluid. GHB urinary excretion is less than 2% of the dose administered. GHB was also detected in sweat at low concentrations. GHB showed a mixed sedative-stimulant pattern with subjective effects peaking between 1 and 1.5 hours after drug administration and lasting for 2 hours. Oral fluid and sweat appeared not to be suitable biologic matrices for monitoring GHB consumption. GHB-mediated subjective effects are related to GHB plasma concentrations.  相似文献   
973.
Exposure to environmental tobacco smoke (ETS) is most often estimated using questionnaires, but they are unreliable. Biomarkers can provide valid information on ETS exposure, the preferred biomarker being cotinine. However, no reference range of hair cotinine exists to distinguish among active, passive, and unexposed nonsmokers. This study identifies cutoffs to validate cotinine as a marker for exposure to ETS. Data were obtained from six databases (four US, one Canada, one France). Active smoking and exposure to ETS were measured in the hair of women of reproductive age, pregnant women, their children, and neonates. Subjects were classified into active smokers, passively exposed to ETS, and unexposed nonsmokers. A total of 1746 cases were available for analysis. For active smokers, mean hair cotinine concentrations (95% confidence interval) were 2.3 to 3.1 ng/mg for nonpregnant women and 1.5 to 1.9 ng/mg for pregnant women. In the group of passive smokers, mean hair cotinine concentrations were 0.5 to 0.7 ng/mg for nonpregnant women, 0.04 to 0.09 ng/mg for pregnant women, 0.9 to 1.1 for children, and 1.2 to 1.7 for neonates. Among unexposed nonsmokers, mean hair cotinine was 0.2 to 0.4 ng/mg in nonpregnant women, 0.06 to 0.09 ng/mg in pregnant women, and 0.3 to 0.4 ng/mg in children. Cutoff values for hair cotinine were established to distinguish active smokers from passive or unexposed (0.8 ng/mg for nonpregnant women and 0.2 ng/mg for pregnant women). A cutoff value of 0.2 ng/mg was accurate in discriminating between exposed children and unexposed. These new values should facilitate clinical diagnosis of active and passive exposure to tobacco smoke. Such diagnosis is critical in pregnancy and in a large number of tobacco-induced medical conditions.  相似文献   
974.

Background

Glecaprevir and Pibrentasvir (G/P) determine high rates of sustained virological response (SVR) with optimal safety profile in patients with chronic hepatitis C virus (HCV) infection. The efficacy and safety of G/P in Caucasian patients aged 75 years and older have not been widely analysed.

Methods

This is a retrospective multicentre real-world study enrolling all consecutive patients 75 years and older who received G/P between October 2017 and January 2022 at five referral centres in Italy. SVR was analysed by intention-to-treat (ITT) and per-protocol analyses (PP).

Results

A total of 570 patients met the inclusion criteria and were analysed: mean age was 80 (75–97) years, 356 (62%) were females, 52% (298/570) had HCV-1, 44% (252/570) had HCV-2 and 137 (24%) patients had liver cirrhosis. Four hundred and sixty-three (81%) patients were taking at least one concomitant drug, with 144 (25%) taking ≥5 concomitant drugs. G/P was given for 8 weeks in 488 patients (86%). During treatment, 48 patients (8%) reported side effects, with 10 (2%) patients discontinuing treatment prematurely. Two patients developed treatment-unrelated serious adverse events. Overall, the SVR rate was 97.9% (558/570) by ITT analysis and 99.6% (558/560) by PP analysis. SVR rates remained consistently high among subgroup analysis stratified by genotype, treatment duration, fibrosis stage and concomitant medications.

Conclusions

Treatment with G/P achieved 97.9% SVR rates in HCV patients older than 75 years of age. Safety was optimal with only 2% of patients discontinuing early.  相似文献   
975.
Investigational New Drugs - Our group recently demonstrated that K858, an inhibitor of motor kinesin Eg5, has important antiproliferative and apoptotic effects on breast cancer, prostatic cancer,...  相似文献   
976.
977.
978.
979.
In the present work, dispersive liquid-liquid microextraction (DLLME) was used to extract six synthetic cannabinoids (JWH-018, JWH-019, JWH-073, JWH-200, or WIN 55,225, JWH-250, and AM-694) from oral fluids. A rapid baseline separation of the analytes was achieved on a bidentate octadecyl silica hydride phase (Cogent Bidentate C18; 4.6 mm × 250 mm, 4 μm) maintained at 37 °C, by eluting in isocratic conditions (water:acetonitrile (25:75, V/V)). Detection was performed using positive electrospray ionization–tandem mass spectrometry. The parameters affecting DLLME (pH and ionic strength of the aqueous phase, type and volume of the extractant and dispersive solvent, vortex and centrifugation time) were optimized for maximizing yields. In particular, using 0.5 mL of oral fluid, acetonitrile (1 mL), was identified as the best option, both as a solvent to precipitate proteins and as a dispersing solvent in the DLLME procedure. To select an extraction solvent, a low transition temperature mixture (LTTM; composed of sesamol and chlorine chloride with a molar ratio of 1:3) and dichloromethane were compared; the latter (100 μL) was proved to be a better extractant, with recoveries ranging from 73% to 101 % by vortexing for 2 min. The method was validated according to the guidelines of Food and Drug Administration bioanalytical methods: intra-day and inter-day precisions ranged between 4 % and 18 % depending on the spike level and analyte; limits of detection spanned from 2 to 18 ng/mL; matrix-matched calibration curves were characterized by determination coefficients greater than 0.9914. Finally, the extraction procedure was compared with previous methods and with innovative techniques, presenting superior reliability, rapidity, simplicity, inexpensiveness, and efficiency.  相似文献   
980.
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