992 resultados para 414
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BACKGROUND: Highly active antiretroviral therapy (HAART) is being scaled up in developing countries. We compared baseline characteristics and outcomes during the first year of HAART between HIV-1-infected patients in low-income and high-income settings. METHODS: 18 HAART programmes in Africa, Asia, and South America (low-income settings) and 12 HIV cohort studies from Europe and North America (high-income settings) provided data for 4810 and 22,217, respectively, treatment-naive adult patients starting HAART. All patients from high-income settings and 2725 (57%) patients from low-income settings were actively followed-up and included in survival analyses. FINDINGS: Compared with high-income countries, patients starting HAART in low-income settings had lower CD4 cell counts (median 108 cells per muL vs 234 cells per muL), were more likely to be female (51%vs 25%), and more likely to start treatment with a non-nucleoside reverse transcriptase inhibitor (NNRTI) (70%vs 23%). At 6 months, the median number of CD4 cells gained (106 cells per muL vs 103 cells per muL) and the percentage of patients reaching HIV-1 RNA levels lower than 500 copies/mL (76%vs 77%) were similar. Mortality was higher in low-income settings (124 deaths during 2236 person-years of follow-up) than in high-income settings (414 deaths during 20,532 person-years). The adjusted hazard ratio (HR) of mortality comparing low-income with high-income settings fell from 4.3 (95% CI 1.6-11.8) during the first month to 1.5 (0.7-3.0) during months 7-12. The provision of treatment free of charge in low-income settings was associated with lower mortality (adjusted HR 0.23; 95% CI 0.08-0.61). INTERPRETATION: Patients starting HAART in resource-poor settings have increased mortality rates in the first months on therapy, compared with those in developed countries. Timely diagnosis and assessment of treatment eligibility, coupled with free provision of HAART, might reduce this excess mortality.
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Gastrin-releasing peptide receptors (GRP-R) are upregulated in many cancers, including prostate, breast, and lung. We describe a new radiolabeled bombesin (BBN) analog for imaging and systemic radiotherapy that has improved pharmacokinetics (PK) and better retention of radioactivity in the tumor. METHODS: DO3A-CH2CO-G-4-aminobenzoyl-Q-W-A-V-G-H-L-M-NH2 (AMBA) was synthesized and radiolabeled. The human prostate cancer cell line PC-3 was used to determine the binding (Kd), retention, and efflux of 177Lu-AMBA. Receptor specificity was determined by in vitro autoradiography in human tissues. PK and radiotherapy studies were performed in PC-3 tumor-bearing male nude mice. RESULTS: 177Lu-AMBA has a high affinity for the GRP-R (Kd, 1.02 nmol/L), with a maximum binding capacity (Bmax) of 414 fmol/10(6) cells (2.5 x 10(5) GRP-R/cell). Internalization was similar for 177Lu-AMBA (76.8%), 177Lu-BBN8 (72.9%), and 125I-[Tyr4]-BBN (74.9%). Efflux was markedly lower for 177Lu-AMBA (2.9%) compared with 177Lu-BBN8 (15.9%) and 125I-[Tyr4]-BBN (46.1%). By receptor autoradiography, Lu-AMBA binds specifically to GRP-R (0.8 nmol/L) and to the neuromedin B receptor (NMB-R) (0.9 nmol/L), with no affinity for the bb3 receptor (>1,000 nmol/L). 177Lu-AMBA was renally excreted (55 %ID 1 h [percentage injected dose at 1 h]); tumor uptake at 1 and 24 h was 6.35 %ID/g and 3.39 %ID/g, respectively. One or 2 doses of 177Lu-AMBA (27.75 MBq/dose) significantly prolonged the life span of PC-3 tumor-bearing mice (P < 0.001 and P < 0.0001, respectively) and decreased PC-3 tumor growth rate over controls. When compared using World Health Organization criteria, mice receiving 2 doses versus 1 dose of 177Lu-AMBA demonstrated a shift away from stable/progressive disease toward complete/partial response; by RECIST (Response Evaluation Criteria in Solid Tumors), median survival increased by 36% and time to progression/progression-free survival increased by 65%. CONCLUSION: 177Lu-AMBA binds with nanomolar affinity to GRP-R and NMB-R, has low retention of radioactivity in kidney, demonstrates a very favorable risk-benefit profile, and is in phase I clinical trials.
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Objective: The aim of this literature review, performed within the framework of the Swiss governmental Program of Evaluation of Complementary Medicine (PEK), was to investigate costs of complementary and alternative medicine (CAM). Materials and Methods: A systematic literature search was conducted in 11 electronic databases. All retrieved titles and reference lists were also hand-searched. Results: 38 publications were found: 23 on CAM of various definitions (medical and non-medical practitioners, over-the-counter products), 13 on homeopathy, 2 on phytotherapy. Studies investigated different kinds of costs (direct or indirect) and used different methods (prospective or retrospective questionnaires, data analyses, cost-effectiveness models). Most studies report 'out of pocket' costs, because CAM is usually not covered by health insurance. Costs per CAM-treatment / patient / month were AUD 7-66, CAD 250 and GBP 13.62 +/- 1.61. Costs per treatment were EUR 205 (range: 15-1,278), USD 414 +/- 269 and USD 1,127. In two analyses phytotherapy proved to be cost-effective. One study revealed a reduction of 1.5 days of absenteeism from work in the CAM group compared to conventionally treated patients. Another study, performed by a health insurance company reported a slight increase in direct costs for CAM. Costs for CAM covered by insurance companies amounted to approximately 0.2-0.5% of the total healthcare budget (Switzerland, 2003). Publications had several limitations, e.g. efficacy of therapies was rarely reported. As compared to conventional patients, CAM patients tend to cause lower costs. Conclusion: Results suggest lower costs for CAM than for conventional patients, but the limited methodological quality lowers the significance of the available data. Further well-designed studies and models are required.
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A double-blinded, randomised, placebo-controlled field study of the influence of prostaglandin E2 (PGE2) on cattle at parturition was carried out. The extent of cervical opening and the intensity of labour were scored before administration of the compound and 10 minutes later; routine birth assistance was then continued by the veterinarian. Successful birth occurred more quickly in the cows treated with PGE2. The extent of cervical opening before the administration of the drug had a significant effect on the time to delivery, but the intensity of labour and a concomitant infusion of calcium did not have significant effects on this period. The less open the cervix before administration of the drug, the more the duration of parturition differed between the two groups, with the placebo group taking longer. A telephone follow-up inquiry found no significant differences between the cows postpartum; there were cases of mastitis and hypocalcaemia in both groups. The incidence of retained fetal membranes and the mortality of the calves were higher in the placebo group, but in neither case was the difference significant.
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The role of macrophages in the clearance of particles with diameters less than 100 nm (ultrafine or nanoparticles) is not well established, although these particles deposit highly efficiently in peripheral lungs, where particle phagocytosis by macrophages is the primary clearance mechanism. To investigate the uptake of nanoparticles by lung phagocytes, we analyzed the distribution of titanium dioxide particles of 20 nm count median diameter in macrophages obtained by bronchoalveolar lavage at 1 hour and 24 hours after a 1-hour aerosol inhalation. Differential cell counts revealing greater than 96% macrophages and less than 1% neutrophils and lymphocytes excluded inflammatory cell responses. Employing energy-filtering transmission electron microscopy (EFTEM) for elemental microanalysis, we examined 1,594 macrophage profiles in the 1-hour group (n = 6) and 1,609 in the 24-hour group (n = 6). We found 4 particles in 3 macrophage profiles at 1 hour and 47 particles in 27 macrophage profiles at 24 hours. Model-based data analysis revealed an uptake of 0.06 to 0.12% ultrafine titanium-dioxide particles by lung-surface macrophages within 24 hours. Mean (SD) particle diameters were 31 (8) nm at 1 hour and 34 (10) nm at 24 hours. Particles were localized adjacent (within 13-83 nm) to the membrane in vesicles with mean (SD) diameters of 592 (375) nm at 1 hour and 414 (309) nm at 24 hours, containing other material like surfactant. Additional screening of macrophage profiles by conventional TEM revealed no evidence for agglomerated nanoparticles. These results give evidence for a sporadic and rather unspecific uptake of TiO(2)-nanoparticles by lung-surface macrophages within 24 hours after their deposition, and hence for an insufficient role of the key clearance mechanism in peripheral lungs.
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OBJECTIVES: To assess perioperative outcomes and blood pressure (BP) responses to an implantable carotid sinus baroreflex activating system being investigated for the treatment of resistant hypertension. METHODS: We report on the first seventeen patients enrolled in a multicenter study. Bilateral perivascular carotid sinus electrodes (CSL) and a pulse generator (IPG) are permanently implanted. Optimal placement of the CSL is determined by intraoperative BP responses to test activations. Acute BP responses were tested postoperatively and during the first four months of follow-up. RESULTS: Prior to implant, BP was 189.6+/-27.5/110.7+/-15.3 mmHg despite stable therapy (5.2+/-1.8 antihypertensive drugs). The mean procedure time was 202+/-43 minutes. No perioperative strokes or deaths occurred. System tests performed 1 or up to 3 days postoperatively resulted in significant (all p < or = 0.0001) mean maximum reduction, with standard deviations and 95% confidence limits for systolic BP, diastolic BP and heart rate of 28+/-22 (17, 39) mmHg, 16+/-11 (10, 22) mmHg and 8+/-4 (6, 11) BPM, respectively. Repeated testing during 3 months of therapeutic electrical activation demonstrated a durable response. CONCLUSIONS: These preliminary data suggest an acceptable safety of the procedure with a low rate of adverse events and support further clinical development of baroreflex activation as a new concept to treat resistant hypertension.
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PURPOSE: To prospectively determine the accuracy of 64-section computed tomographic (CT) angiography for the depiction of coronary artery disease (CAD) that induces perfusion defects at myocardial perfusion imaging with single photon emission computed tomography (SPECT), by using myocardial perfusion imaging as the reference standard. MATERIALS AND METHODS: All patients gave written informed consent after the study details, including radiation exposure, were explained. The study protocol was approved by the local institutional review board. In patients referred for elective conventional coronary angiography, an additional 64-section CT angiography study and a myocardial perfusion imaging study (1-day adenosine stress-rest protocol) with technetium 99m-tetrofosmin SPECT were performed before conventional angiography. Coronary artery diameter narrowing of 50% or greater at CT angiography was defined as stenosis and was compared with the myocardial perfusion imaging findings. Quantitative coronary angiography served as a reference standard for CT angiography. RESULTS: A total of 1093 coronary segments in 310 coronary arteries in 78 patients (mean age, 65 years +/- 9 [standard deviation]; 35 women) were analyzed. CT angiography revealed stenoses in 137 segments (13%) corresponding to 91 arteries (29%) in 46 patients (59%). SPECT revealed 14 reversible, 13 fixed, and six partially reversible defects in 31 patients (40%). Sensitivity, specificity, and negative and positive predictive values, respectively, of CT angiography in the detection of reversible myocardial perfusion imaging defects were 95%, 53%, 94%, and 58% on a per-patient basis and 95%, 75%, 96%, and 72% on a per-artery basis. Agreement between CT and conventional angiography was very good (96% and kappa = 0.92 for patient-based analysis, 93% and kappa = 0.84 for vessel-based analysis). CONCLUSION: Sixty-four-section CT angiography can help rule out hemodynamically relevant CAD in patients with intermediate to high pretest likelihood, although an abnormal CT angiography study is a poor predictor of ischemia.
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Inexpensive, commercial available off-the-shelf (COTS) Global Positioning Receivers (GPS) have typical accuracy of ±3 meters when augmented by the Wide Areas Augmentation System (WAAS). There exist applications that require position measurements between two moving targets. The focus of this work is to explore the viability of using clusters of COTS GPS receivers for relative position measurements to improve their accuracy. An experimental study was performed using two clusters, each with five GPS receivers, with a fixed distance of 4.5 m between the clusters. Although the relative position was fixed, the entire system of ten GPS receivers was on a mobile platform. Data was recorded while moving the system over a rectangular track with a perimeter distance of 7564 m. The data was post processed and yielded approximately 1 meter accuracy for the relative position vector between the two clusters.
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OBJECTIVE: To investigate the effect of plasma concentrations obtained by a low dose constant rate infusion (CRI) of racemic ketamine or S-ketamine on the nociceptive withdrawal reflex (NWR) in standing ponies. STUDY DESIGN: Prospective, blinded, cross-over study. ANIMALS: Six healthy 5-year-old Shetland ponies. METHODS: Ponies received either 0.6 mg kg(-1) racemic ketamine (group RS) or 0.3 mg kg(-1) S-ketamine (group S) intravenously (IV), followed by a CRI of 20 microg kg(-1)minute(-1) racemic ketamine (group RS) or 10 microg kg(-1)minute(-1) S-ketamine (group S) for 59 minutes. The NWR was evoked by transcutaneous electrical stimulation of a peripheral nerve before drug administration, 15 and 45 minutes after the start of the bolus injection and 15 minutes after the end of the CRI. Electromyographic responses were recorded and analysed. Arterial blood was collected before stimulation and plasma concentrations of ketamine and norketamine were measured enantioselectively using capillary electrophoresis. Ponies were video recorded and monitored to assess drug effects on behaviour, heart rate (HR), mean arterial blood pressure (MAP) and respiratory rate. RESULTS: The NWR was significantly depressed in group RS at plasma concentrations between 20 and 25 ng mL(-1) of each enantiomer. In group S, no significant NWR depression could be observed; plasma concentrations of S-ketamine (9-15 ng mL(-1)) were lower, compared to S-ketamine concentrations in group RS, although this difference was not statistically significant. Minor changes in behaviour, HR and MAP only occurred within the first 5-10 minutes after bolus drug administration in both groups. CONCLUSION: Antinociceptive activity in standing ponies, demonstrated as a depression of the NWR, could only be detected after treatment with racemic ketamine. S-ketamine may have lacked this effect as a result of lower plasma concentrations, a more rapid metabolism or a lower potency of S-ketamine in Equidae so further investigation is necessary.
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We developed a gel- and label-free proteomics platform for comparative studies of human serum. The method involves the depletion of the six most abundant proteins, protein fractionation by Off-Gel IEF and RP-HPLC, followed by tryptic digestion, LC-MS/MS, protein identification, and relative quantification using probabilistic peptide match score summation (PMSS). We evaluated performance and reproducibility of the complete platform and the individual dimensions, by using chromatograms of the RP-HPLC runs, PMSS based abundance scores and abundance distributions as objective endpoints. We were interested if a relationship exists between the quantity ratio and the PMSS score ratio. The complete analysis was performed four times with two sets of serum samples containing different concentrations of spiked bovine beta-lactoglobulin (0.1 and 0.3%, w/w). The two concentrations resulted in significantly differing PMSS scores when compared to the variability in PMSS scores of all other protein identifications. We identified 196 proteins, of which 116 were identified four times in corresponding fractions whereof 73 qualified for relative quantification. Finally, we characterized the PMSS based protein abundance distributions with respect to the two dimensions of fractionation and discussed some interesting patterns representing discrete isoforms. We conclude that combination of Off-Gel electrophoresis (OGE) and HPLC is a reproducible protein fractionation technique, that PMSS is applicable for relative quantification, that the number of quantifiable proteins is always smaller than the number of identified proteins and that reproducibility of protein identifications should supplement probabilistic acceptance criteria.