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91.
The synthesis of 14C‐labeled, 13CD2‐labeled saxagliptin,and its 13CD2‐labeled 5‐hydroxy metabolite
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Scott B. Tran Brad D. Maxwell Kai Cao Samuel J. Bonacorsi 《Journal of labelled compounds & radiopharmaceuticals》2014,57(3):136-140
14C‐labeled saxagliptin, 13CD2‐labeled saxagliptin, and its 13CD2‐labeled 5‐hydroxy metabolite were synthesized to further support development of the compound for biological studies. This paper describes new syntheses leading to the desired compounds. A total of 3.0 mCi of 14C‐labeled saxagliptin was obtained with a specific activity of 53.98 μCi/mg (17.13 mCi/mmol). The radiochemical purity determined by HPLC was 99.29%, and the overall radiochemical yield was 3.0% based upon 100 mCi of [14C]CH2I2 starting material. By following similar synthetic routes, 580.0 mg of 13CD2‐labeled saxagliptin and 153.1 mg of 13CD2‐labeled 5‐hydroxysaxagliptin metabolite were prepared. Copyright © 2014 John Wiley & Sons, Ltd. 相似文献
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Rajesh Thippeshappa Baoping Tian Brad Cleveland Wenjin Guo Patricia Polacino Shiu-Lok Hu 《Clinical and Vaccine Immunology : CVI》2016,23(3):204-212
Human immunodeficiency virus type 1 (HIV-1) acquisition occurs predominantly through mucosal transmission. We hypothesized that greater mucosal immune responses and protective efficacy against mucosal HIV-1 infection may be achieved by prime-boost immunization at mucosal sites. We used a macaque model to determine the safety, immunogenicity, and protective efficacy of orally delivered, replication-competent but attenuated recombinant vaccinia viruses expressing full-length HIV-1 SF162 envelope (Env) or simian immunodeficiency virus (SIV) Gag-Pol proteins. We examined the dose and route that are suitable for oral immunization with recombinant vaccinia viruses. We showed that sublingual inoculation of two vaccinia virus-naive pigtailed macaques with 5 × 108 PFU of recombinant vaccinia viruses was safe. However, sublingual inoculation with a higher dose or tonsillar inoculation resulted in secondary oral lesions, indicating the need to optimize the dose and route for oral immunization with replication-competent vaccinia virus vectors. Oral priming alone elicited antibody responses to vaccinia virus and to the SF162 Env protein. Intramuscular immunization with the SF162 gp120 protein at either 20 or 21 weeks postpriming resulted in a significant boost in antibody responses in both systemic and mucosal compartments. Furthermore, we showed that immune responses induced by recombinant vaccinia virus priming and intramuscular protein boosting provided protection against intrarectal challenge with the simian-human immunodeficiency virus SHIV-SF162-P4. 相似文献
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A. M. Getachew G. Innocent C. J. Proudman A. Trawford G. Feseha S. W. J. Reid B. Faith S. Love 《Parasitology research》2013,112(1):141-146
The efficacy of an oral formulation of praziquantel (Equitape, Horse paste, Fort Dodge) in the reduction of cestode egg counts and serum antibody level against Anoplocephala perfoliata was assessed in 44 donkeys under field conditions. The donkeys were confirmed both by faecal examination and serum antibody assessed by an enzyme-linked immunosorbent assay to have natural infection with tapeworms. The donkeys were randomly allocated into treatment (n?=?22) and control (n?=?22) groups. The treatment group was treated with both praziquantel and ivermectin (Ivomec, Merial) at a dose rate of 1 mg/kg and 200 μg/kg, respectively while the control group was treated only with ivermectin. Faecal samples were collected before treatment (day-0) and 2, 6, 8, 12, and 16 weeks post-treatment while blood samples were collected before treatment and 8 and 16 weeks after treatment and analysed. The results of the study demonstrated that praziquantel paste was highly effective in reducing cestode eggs in donkeys and had an efficacy of more than 99 % until week 16 (day?112). No cestode egg reappearance by 16 weeks post-treatment in any animal in the treatment group was observed while donkeys in the control group continued shedding cestode eggs. The immunological assay also showed a significant reduction in serum antibody level against A. perfoliata in treated donkeys compared to the control group (p?=?0.0001). This marked decrease in serum antibody level indicates reduced risk of cestode-associated colic and other gastrointestinal disorders and clinical diseases. No adverse reactions or clinical effects were encountered in any animal within either group throughout the trial period. 相似文献
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Jason J. S. Barton Andrea Albonico Tirta Susilo Brad Duchaine Sherryse L. Corrow 《Cognitive neuropsychology》2019,36(1-2):54-84
Whether face and object recognition are dissociated in prosopagnosia continues to be debated: a recent review highlighted deficiencies in prior studies regarding the evidence for such a dissociation. Our goal was to study cohorts with acquired and developmental prosopagnosia with a complementary battery of tests of object recognition that address prior limitations, as well as evaluating for residual effects of object expertise. We studied 15 subjects with acquired and 12 subjects with developmental prosopagnosia on three tests: the Old/New Tests, the Cambridge Bicycle Memory Test, and the Expertise-adjusted Test of Car Recognition. Most subjects with developmental prosopagnosia were normal on the Old/New Tests: for acquired prosopagnosia, subjects with occipitotemporal lesions often showed impairments while those with anterior temporal lesions did not. Ten subjects showed a putative classical dissociation between the Cambridge Face and Bicycle Memory Tests, seven of whom had normal reaction times. Both developmental and acquired groups showed reduced car recognition on the expertise-adjusted test, though residual effects of expertise were still evident. Two subjects with developmental prosopagnosia met criteria for normal object recognition across all tests. We conclude that strong evidence for intact object recognition can be found in a few subjects but the majority show deficits, particularly those with the acquired form. Both acquired and developmental forms show residual but reduced object expertise effects. 相似文献
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Brad Wright PhD Canada Parrish PhD MSPH Anirban Basu PhD MS Karen E. Joynt Maddox MD MPH Joshua M. Liao MD. MSc Amber K. Sabbatini MD MPH 《Health services research》2023,58(3):554-559
Objective
To evaluate whether Medicare's Hospital Readmissions Reduction Program (HRRP) is associated with increased observation stay use.Data Sources and Study Setting
A nationally representative sample of fee-for-service Medicare claims, January 2009–September 2016.Study Design
Using a difference-in-difference (DID) design, we modeled changes in observation stays as a proportion of total hospitalizations, separately comparing the initial (acute myocardial infarction, pneumonia, heart failure) and subsequent (chronic obstructive pulmonary disease) target conditions with a control group of nontarget conditions. Each model used 3 time periods: baseline (15 months before program announcement), an intervening period between announcement and implementation, and a 2-year post-implementation period, with specific dates defined by HRRP policies.Data Collection/Extraction Methods
We derived a 20% random sample of all hospitalizations for beneficiaries continuously enrolled for 12 months before hospitalization (N = 7,162,189).Principal Findings
Observation stays increased similarly for the initial HRRP target and nontarget conditions in the intervening period (0.01% points per month [95% CI −0.01, 0.3]). Post-implementation, observation stays increased significantly more for target versus nontarget conditions, but the difference is quite small (0.02% points per month [95% CI 0.002, 0.04]). Results for the COPD analysis were statistically insignificant in both policy periods.Conclusions
The increase in observation stays is likely due to other factors, including audit activity and clinical advances. 相似文献100.