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81.
Recent studies indicate that not only the anthelminthic levamisole but also the racemate tetramisole (R‐/S‐phenyltetraimidazothiazole, PTHIT) was found as an adulterant for cocaine. We herein report on the investigation of the prevalence of PTHIT among cocaine‐positive hair samples and the discrimination of the presence of its stereoisomers levamisole and dexamisole. Cocaine‐positive hair samples were collected in a forensic context in 2015 and mainly 2017 (n = 724). Cocaine and PTHIT concentrations have been determined by achiral liquid chromatography–tandem mass spectrometry (LC–MS/MS). For distinction of levamisole/dexamisole chiral LC–MS/MS was performed. Cocaine hair concentrations ranged from 500 (cut‐off) to approximately 800 000 pg/mg. The study demonstrates a strong prevalence of PTHIT in cocaine users' hair (87%, n = 627). PTHIT hair concentrations ranged from below LLOQ 3.5 to approximately 61 000 pg/mg (median: 260 pg/mg). Surprisingly, enantiomeric ratios of levamisole/dexamisole ranged from 0.17 to 1.34 (median: 0.63). Therefore, PTHIT‐adulterated street cocaine samples (n = 24) seized between 2013 and 2016 were tested. Samples mainly contained racemic tetramisole (87.5%), only one sample contained levamisole only and two samples contained non‐racemic PTHIT. Our experiments suggest that the presence of tetramisole in biological samples may have hitherto been underestimated. Most probably higher dexamisole than levamisole concentrations in hair specimens arise from stereoselective metabolism and/or elimination. This is particularly important in light of the different pharmacological activities of the two enantiomers and potentially different adverse effects. Toxicological interpretations in intoxication cases with adulterated cocaine should not only consider levamisole but also tetramisole and terminology in scientific contributions should be used accordingly. 相似文献
82.
For testing of dynamic light scattering of platelets with ThromboLUX (TLX) in platelet‐rich plasma (PRP) derived from venous whole blood (vWB), anticoagulation is needed. We compared TLX score in PRPs containing citrate, ethylene‐diamine‐tetraacetic‐acid (EDTA), citrate‐phosphate‐dextrose‐adenine (CPDA) or citrate‐theophylline‐adenosine‐dipyridamole. Initial and late TLX scores were measured after 30–120 min or four to six hours, respectively. Compared with citrate, mean differences in initial TLX score were only significant for CPDA. Also, mean differences between initial and late TLX scores were only significant for CPDA. TLX failed to detect EDTA‐induced platelet alterations. The clinical relevance of TLX needs further studies. 相似文献
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84.
Suffoletto B Callaway C Kristan J Kraemer K Clark DB 《Alcoholism, clinical and experimental research》2012,36(3):552-560
Background: Brief interventions have the potential to reduce heavy drinking in young adults who present to the emergency department (ED), but require time and resources rarely available. Text‐messaging (TM) may provide an effective way to collect drinking data from young adults after ED discharge as well as to provide immediate feedback and ongoing support for behavior change. The feasibility of screening young adults in the ED, recruiting them for a TM‐based interventional trial, collecting weekly drinking data through TM, and the variance in drinking outcomes remains unknown. Methods: Young adults in 3 urban EDs (n = 45; aged 18 to 24 years, 54% women) identified as hazardous drinkers by the Alcohol Use Disorders Identification Test‐Consumption score were randomly assigned to weekly TM‐based feedback with goal setting (Intervention), weekly TM‐based drinking assessments without feedback (Assessment), or control. Participants in the Intervention group who reported ≥5 (for men) and ≥4 (for women) maximum drinks during any one 24‐hour period were asked whether they would set a goal to reduce their drinking the following week. We describe the interaction with TM and goal setting. We also describe the heavy drinking days (HDDs), drinks per drinking day (DPDD) using timeline follow‐back procedure at baseline and 3 months. Results: We screened 109 young adults over 157 hours across 24 unique days and 52 (48%; 95% CI 38 to 50) screened positive for hazardous drinking. Of these, 45 (87%; 95% CI 74 to 94) met inclusion criteria, were enrolled and randomized, and 6 (13%; 95% CI 5 to 27) did not complete 3‐month web‐based follow‐up; 88% (95% CI 84 to 91) of weekly TM‐based drinking assessments were answered, with 77% (95% CI 58 to 90) of participants responding to all 12 weeks. Agreeing to set a goal was associated with a repeat HDD 36% (95% CI 17 to 55) of the time compared with 63% (95% CI 44 to 81) when not willing to set a goal. At 3 months, participants that were exposed to the TM‐based intervention had 3.4 (SD 5.4) fewer HDDs in the last month and 2.1 (SD 1.5) fewer DPDD when compared to baseline. Conclusions: TM can be used to assess drinking in young adults and can deliver brief interventions to young adults discharged from the ED. TM‐based interventions have the potential to reduce heavy drinking among young adults but larger studies are needed to establish efficacy. 相似文献
85.
Zhan B Santiago H Keegan B Gillespie P Xue J Bethony J de Oliveira LM Jiang D Diemert D Xiao SH Jones K Feng X Hotez PJ Bottazzi ME 《Parasite immunology》2012,34(8-9):404-411
Na-ASP-2 is a major protein secreted by infective third-stage larvae (L3) of the human hookworm Necator americanus upon host entry. It was chosen as a lead vaccine candidate for its ability to elicit protective immune responses. However, clinical development of this antigen as a recombinant vaccine was halted because it caused allergic reactions among some of human volunteers previously infected with N.?americanus. To prevent IgE-mediated allergic reactions induced by Na-ASP-2 but keep its immunogenicity as a vaccine antigen, we designed and tested a genetically engineered fusion protein, Fcγ/Na-ASP-2, composed of full-length Na-ASP-2 and truncated human IgG Fcγ1 that targets the negative signalling receptor FcγRIIb expressed on pro-allergic cells. The chimeric recombinant Fcγ/Na-ASP-2 protein was expressed in Pichia pastoris and shared the similar antigenicity as native Na-ASP-2. Compared to Na-ASP-2, the chimeric fusion protein efficiently reduced the release of histamine in human basophils sensitized with anti-Na-ASP-2 IgE obtained from individuals living in a hookworm-endemic area. In dogs infected with canine hookworm, Fcγ/Na-ASP-2 resulted in significantly reduced immediate-type skin reactivity when injected intradermally compared with Na-ASP-2. Hamsters vaccinated with Fcγ/Na-ASP-2 formulated with Alhydrogel(?) produced specific IgG that recognized Na-ASP-2 and elicited similar protection level against N.?americanus L3 challenge as native Na-ASP-2. 相似文献
86.
Dumas de La Roque E Savineau JP Metivier AC Billes MA Kraemer JP Doutreleau S Jougon J Marthan R Moore N Fayon M Baulieu EÉ Dromer C 《Annales d'endocrinologie》2012,73(1):20-25
ObjectivesIt was previously shown that dehydroepiandrosterone (DHEA) reverses chronic hypoxia-induced pulmonary hypertension (PH) in rats, but whether DHEA can improve the clinical and hemodynamic status of patients with PH associated to chronic obstructive pulmonary disease (PH-COPD) has not been studied whereas it is a very severe poorly treated disease.Patients and methodsEight patients with PH-COPD were treated with DHEA (200 mg daily orally) for 3 months. The primary end-point was the change in the 6-minute walk test (6-MWT) distance. Secondary end-points included pulmonary hemodynamics, lung function tests and tolerance of treatment.ResultsThe 6-MWT increased in all cases, from 333 m (median [IQR]) (257; 378) to 390 m (362; 440) (P < 0.05). Mean pulmonary artery pressure decreased from 26 mmHg (25; 27) to 21.5 mmHg (20; 25) (P < 0.05) and pulmonary vascular resistance from 4.2 UI (3.5; 4.4) to 2.6 UI (2.5; 3.8) (P < 0.05). The carbon monoxide diffusing capacity of the lung (DLCO % predicted) increased significantly from 27.4% (20.1; 29.3) to 36.4% (14.6; 39.6) (P < 0.05). DHEA treatment did not change respiratory parameters of gas exchange and the 200 mg per day of DHEA used was perfectly tolerated with no side effect reported.ConclusionDHEA treatment significantly improves 6-MWT distance, pulmonary hemodynamics and DLCO of patients with PH-COPD, without worsening gas exchange, as do other pharmacological treatments of PH (trial registration NCT00581087). 相似文献
87.
Worm PV Ferreira NP Ferreira MP Kraemer JL Lenhardt R Alves RP Wunderlich RC Collares MV 《The Journal of craniofacial surgery》2012,23(3):650-653
Current methods to evaluate the biologic development of bone grafts in human beings do not quantify results accurately. Cranial burr holes are standardized critical bone defects, and the differences between bone powder and bone grafts have been determined in numerous experimental studies. This study evaluated quantitative computed tomography (QCT) as a method to objectively measure cranial bone density after cranial reconstruction with autografts. In each of 8 patients, 2 of 4 surgical burr holes were reconstructed with autogenous wet bone powder collected during skull trephination, and the other 2 holes, with a circular cortical bone fragment removed from the inner table of the cranial bone flap. After 12 months, the reconstructed areas and a sample of normal bone were studied using three-dimensional QCT; bone density was measured in Hounsfield units (HU). Mean (SD) bone density was 1535.89 (141) HU for normal bone (P < 0.0001), 964 (176) HU for bone fragments, and 453 (241) HU for bone powder (P < 0.001). As expected, the density of the bone fragment graft was consistently greater than that of bone powder. Results confirm the accuracy and reproducibility of QCT, already demonstrated for bone in other locations, and suggest that it is an adequate tool to evaluate cranial reconstructions. The combination of QCT and cranial burr holes is an excellent model to accurately measure the quality of new bone in cranial reconstructions and also seems to be an appropriate choice of experimental model to clinically test any cranial bone or bone substitute reconstruction. 相似文献
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90.
In March 2010, the Patient Protection and Affordable Care Act as well as its amendments were signed into law. This sweeping legislation was aimed at controlling spiraling healthcare costs and redressing significant disparities in healthcare access and quality. Cancer diagnoses and their treatments constitute a large component of rising healthcare expenditures and, not surprisingly, the legislation will have a significant influence on cancer care in the USA. Because genitourinary malignancies represent an impressive 25% of all cancer diagnoses per year, this legislation could have a profound impact on urologic oncology. To this end, we will present key components of this landmark legislation, including the proposed expansion to Medicaid coverage, the projected role of Accountable Care Organizations, the expected creation of quality reporting systems, the formation of an independent Patient-Centered Outcomes Research Institute, and enhanced regulation on physician-owned practices. We will specifically address the anticipated effect of these changes on urologic cancer care. Briefly, the legal ramifications and current barriers to the statutes will be examined. 相似文献