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31.
Madörin Maya van Hoogevest Peter Hilfiker Rolf Langwost Birgit Kresbach Gerhard M. Ehrat Markus Leuenberger Hans 《Pharmaceutical research》1997,14(12):1706-1712
Purpose. The applicability of Asymmetrical Flow Field-Flow Fractionation (Asymmetrical Flow FFF) as an alternative tool to examine the distribution of a lipophilic drug (N-Benzoyl-staurosporine) within human plasma protein fractions was investigated with respect to high separation speed and loss of material on surfaces due to adsorption.
Methods. Field-Flow Fractionation is defined as a group of pseudo-chromatographic separation methods, where compounds are separated under the influence of an externally applied force based on differences in their physicochemical properties. This method was used to separate human plasma in its protein fractions. The drug distribution in the fractions was investigated by monitoring the fractionated eluate for drug content by fluorescence spectroscopy.
Results. Human plasma was separated into human serum albumin (HSA), high density lipoprotein (HDL), 2-macroglobulin and low density lipoprotein (LDL) fractions in less than ten minutes. Calibration of the system and identification of the individual fractions was performed using commercially available protein reference standards. The influence of membrane type and carrier solution composition on the absolute recovery of N-Benzoyl-staurosporine and fluorescein-isothio-cyanate-albumin (FITC-albumin) was found to be quite significant. Both factors were optimized during the course of the investigations. N-Benzoyl-staurosporine was found to be enriched in the fraction containing HSA.
Conclusions. If experimental conditions are thoroughly selected and controlled to suppress drug and plasma protein adsorption at the separation membrane, Asymmetrical Flow FFF shows high recoveries and fast separation of human plasma proteins, and can be a reliable tool to characterize drug / plasma protein interactions. For analytical purposes it has the potential to rival established technologies like ultracentrifugation in terms of ease-of-use, precision, and separation time. 相似文献
32.
OBJECTIVE: To study alterations of serum levels of the pancreatic reg family of proteins in two models of acute pancreatitis. SUMMARY BACKGROUND DATA: The pancreatic reg family of proteins is expressed in the acinar pancreas. Reg I (pancreatic stone protein, PSP) and reg III (pancreatitis-associated protein, PAP) are induced after the onset of acute pancreatitis, and both have been proposed as potential markers of pancreatitis. METHODS: Pancreatitis was induced in rats by either retrograde infusion of sodium taurocholate or by direct trauma. Serum samples were obtained daily for 4 days after the procedure, and the animals were then killed. Twelve animals underwent sham procedure and six underwent daily analysis without surgery. Levels of reg I/PSP and reg III/PAP were estimated by enzyme-linked immunosorbent assay. RESULTS: Reg III/PAP levels increased significantly the first day after induction of both types of pancreatitis and rapidly returned to baseline in all survivors. Even animals who received retrograde infusion of saline showed a mild increase in reg III/PAP on the first day, whereas control animals that did not undergo surgery showed no variations. Reg I/PSP serum levels remained unchanged throughout all experimental periods. Postinjury reg III/PAP levels significantly correlated with severity of the pancreatic injury and animal survival; reg I/PSP levels did not. CONCLUSION: After induction of pancreatitis, serum levels of reg I and III protein differ significantly. Reg III/PAP levels are a sensitive marker of pancreatic injury and early in the disease may be a useful prognostic indicator for disease severity. 相似文献
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The full stereochemical characterization of 4-methylproline, a rare amino acid found in a number of peptidic secondary metabolites, has often been hindered by long reaction sequences or low stereoselectivity in the synthesis leading to reference samples. The preparation of the four diastereoisomers of 4-methylproline by a concise and stereoselective route is presented and features a six-step route with late-stage stereodivergence, good stereoselectivity for both cis- and trans-series (75% and 88% de, respectively), and good overall yields (cumulative yields of 30-40%). Additional data on the Marfey's derivatives of the stereoisomers are also presented. 相似文献
37.
Subinhibitory concentrations of antibiotics were found to enhance and modulate the production of new phenazines, streptophenazines A-H, in a marine Streptomyces isolate. The streptophenazines differ in length and substitution of an alkyl chain. The pattern of metabolites formed depends on the antibiotic used. In the presence of tetracycline, streptophenazines F and G were induced and the production of streptophenazines A-D was increased. When using bacitracin, mainly streptophenazine H was produced. Streptophenazines C and H showed moderate activity against Bacillus subtilis, while streptophenazine C was also active against Staphylococcus lentus. 相似文献
38.
Mary E. Patrick Kelly A. Shaw Patricia M. Dietz Jon Baio Marshalyn Yeargin-Allsopp Deborah A. Bilder Russell S. Kirby Jennifer A. Hall-Lande Rebecca A. Harrington Li-Ching Lee Maya Liza C. Lopez Julie Daniels Matthew J. Maenner 《Disability and health journal》2021,14(2):101023
BackgroundChildren with intellectual disability (ID), characterized by impairments in intellectual functioning and adaptive behavior, benefit from early identification and access to services. Previous U.S. estimates used administrative data or parent report with limited information for demographic subgroups.ObjectiveUsing empiric measures we examined ID characteristics among 8-year-old children and estimated prevalence by sex, race/ethnicity, geographic area and socioeconomic status (SES) area indicators.MethodsWe analyzed data for 8-year-old children in 9 geographic areas participating in the 2014 Autism and Developmental Disabilities Monitoring Network. Children with ID were identified through record review of IQ test data. Census and American Community Survey data were used to estimate the denominator.ResultsOverall, 11.8 per 1,000 (1.2%) had ID (IQ ≤ 70), of whom 39% (n = 998) also had autism spectrum disorder. Among children with ID, 1,823 had adaptive behavior test scores for which 64% were characterized as impaired. ID prevalence per 1,000 was 15.8 (95% confidence interval [95% CI], 15.0–16.5) among males and 7.7 (95% CI, 7.2–8.2) among females. ID prevalence was 17.7 (95% CI, 16.6–18.9) among children who were non-Hispanic black; 12.0 (95% CI, 11.1–13.0), among Hispanic; 8.6 (95% CI, 7.1–10.4), among non-Hispanic Asian; and 8.0 (95% CI, 7.5–8.6), among non-Hispanic white. Prevalence varied across geographic areas and was inversely associated with SES.ConclusionsID prevalence varied substantively among racial, ethnic, geographic, and SES groups. Results can inform strategies to enhance identification and improve access to services particularly for children who are minorities or living in areas with lower SES. 相似文献
39.
Rachael N. Martinez Bridget M. Smith Dustin D. French Timothy P. Hogan Beverly Gonzalez Chad M. Osteen Maya Hatch Vicki Anderson Elizabeth Tarlov Abigail Silva Barry Goldstein Kevin T. Stroupe 《The journal of spinal cord medicine》2022,45(4):575
Context/Objective: Provisions of the Affordable Care Act (ACA) potentially increase insurance options for Veterans with disabilities. We examined Veterans with spinal cord injuries and disorders (SCI/D) to assess whether the ACA was associated with changes in healthcare utilization from Department of Veterans Affairs (VA) healthcare facilities.Design: Using national VA data, we investigated impacts on VA healthcare utilization pre- (2012/13) and post-ACA (2014/15) implementation with negative binomial regression models.Setting: VA healthcare facilities.Participants: 8,591 VA users with SCI/D. Veterans with acute myelitis, Guillain-Barré syndrome, multiple sclerosis, or amyotrophic lateral sclerosis were excluded as were patients who died during the study period.Interventions: We assessed VA healthcare utilization before and after ACA implementation.Outcome Measures: Total numbers of VA visits for SCI/D care, diagnostic care, primary care, specialty care, and mental health care, and VA admissions.Results: The number of VA admissions was 7% higher in the post than pre-ACA implementation period (P < 0.01). The number of VA visits post-implementation increased for SCI/D care (8%; P < 0.01) and specialty care (12%; P < 0.001). Conversely, the number of mental health visits was 17% lower in the post-ACA period (P < 0.001). Veterans with SCI/D who live <5 miles from their nearest VA facility received VA care more frequently than those ≥40 miles from VA (P < 0.001).Conclusion: Counter to expectations, results suggest that Veterans with SCI/D sought more frequent VA care after ACA implementation, indicating Veterans with SCI/D continue to utilize the lifelong, comprehensive care provided at VA. 相似文献
40.
Belgium has actively participated in clinical research on severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) since the beginning of the pandemic to help identify effective and safe treatments for COVID-19. The objective of this review is to provide a picture of the clinical studies carried out in hospitalized patients with COVID-19 in Belgium. We collected data on all randomized, interventional trials in patients with COVID-19 that were registered on two recognized clinical trial registers, started enrollment before 31 December 2021, and included at least one patient in a Belgian center. Data were collected concerning the therapies investigated and the nature of the trials performed. Thirty-three hospitals (32% of all Belgian hospitals) participated in at least one of 28 trials (13 sponsored by the industry and 15 by academic centers) on therapeutics for COVID-19 in hospitalized patients: 7 (25%) evaluated antivirals, 17 (61%) immunomodulators, 2 (7%) anti-coagulants, and 1 (3%) nitric oxide to improve respiratory function. Nineteen (68%) were phase II trials. Only three (11%) of the trials were international platform trials. Despite numerous trials, less than 3% of all Belgian patients hospitalized with COVID-19 participated in a clinical trial on therapeutics. As in many other countries, more efforts could have been made to avoid running small, under-powered, mono- or bicenter trials, to create better collaboration between the different Belgian hospitals, and to participate in more international clinical trials, and more specifically in adaptive, platform trials. 相似文献