Proteoglycans (PGs), consisting of glycosaminoglycans (GAGs) linked with the core protein through a tetrasaccharide linkage region, play roles in many important biological events. The chemical ...synthesis of PG glycopeptides is extremely challenging. In this work, the enzymes required for synthesis of chondroitin sulfate (CS) PG (CSPG) have been expressed and the suitable sequence of enzymatic reactions has been established. To expedite CSPG synthesis, the peptide acceptor was immobilized on solid phase and the glycan units were directly installed enzymatically onto the peptide. Subsequent enzymatic chain elongation and sulfation led to the successful synthesis of CSPG glycopeptides. The CS dodecasaccharide glycopeptide was the longest homogeneous CS glycopeptide synthesized to date. The enzymatic synthesis was much more efficient than the chemical synthesis of the corresponding CS glycopeptides, which could reduce the total number of synthetic steps by 80%. The structures of the CS glycopeptides were confirmed by mass spectrometry analysis and NMR studies. In addition, the interactions between the CS glycopeptides and cathepsin G were studied. The sulfation of glycan chain was found to be important for binding with cathepsin G. This efficient chemoenzymatic strategy opens new avenues to investigate the structures and functions of PGs.
As genomic sequencing expands, so does our knowledge of the link between genetic variation and disease. Deeper catalogs of variant frequencies improve identification of benign variants, while ...sequencing affected individuals reveals disease‐associated variation. Accumulation of human genetic data thus makes reanalysis a means to maximize the benefits of clinical sequencing. We implemented pipelines to systematically reassess sequencing data from 494 individuals with developmental disability. Reanalysis yielded pathogenic or likely pathogenic (P/LP) variants that were not initially reported in 23 individuals, 6 described here, comprising a 16% increase in P/LP yield. We also downgraded 3 LP and 6 variants of uncertain significance (VUS) due to updated population frequency data. The likelihood of identifying a new P/LP variant increased over time, as ~22% of individuals who did not receive a P/LP variant at their original analysis subsequently did after 3 years. We show here that reanalysis and data sharing increase the diagnostic yield and accuracy of clinical sequencing.
Background Early-life human rhinovirus infection has been linked to asthma development in high-risk infants and children. Nevertheless, the role of rhinovirus infection in the initiation of asthma ...remains unclear. Objective We hypothesized that, in contrast to infection of mature BALB/c mice, neonatal infection with rhinovirus promotes an IL-25–driven type 2 response, which causes persistent mucous metaplasia and airways hyperresponsiveness. Methods Six-day-old and 8-week-old BALB/c mice were inoculated with sham HeLa cell lysate or rhinovirus. Airway responses from 1 to 28 days after infection were assessed by using quantitative PCR, ELISA, histology, immunofluorescence microscopy, flow cytometry, and methacholine responsiveness. Selected mice were treated with a neutralizing antibody to IL-25. Results Compared with mature mice, rhinovirus infection in neonatal mice increased lung IL-13 and IL-25 production, whereas IFN-γ, IL-12p40, and TNF-α expression was suppressed. In addition, the population of IL-13–secreting type 2 innate lymphoid cells (ILC2s) was expanded with rhinovirus infection in neonatal but not mature mice. ILC2s were the major cell type secreting IL-13 in neonates. Finally, anti–IL-25 neutralizing antibody attenuated ILC2 expansion, mucous hypersecretion, and airways responsiveness. Conclusions These findings suggest that early-life viral infection could contribute to asthma development by provoking age-dependent, IL-25–driven type 2 immune responses.
Abstract Objective To provide a framework for implementation of multicomponent, school-based nutrition interventions. This article describes the research methods for the Shaping Healthy Choices ...Program, a model to improve nutrition and health-related knowledge and behaviors among school-aged children. Design Longitudinal, pretest/posttest, randomized, controlled intervention. Setting Four elementary schools in California. Participants Fourth-grade students at intervention (n = 252) and control (n = 238) schools and their parents and teachers. Power analyses demonstrate that a minimum of 159 students per group will be needed to achieve sufficient power. The sample size was determined using the variables of nutrition knowledge, vegetable preference score, and body mass index percentile. Intervention A multicomponent school-based nutrition education intervention over 1 academic year, followed by activities to support sustainability of the program. Main Outcome Measures Dietary and nutrition knowledge and behavior, critical thinking skills, healthy food preferences and consumption, and physical activity will be measured using a nutrition knowledge questionnaire, a food frequency questionnaire, a vegetable preferences assessment tool, the Test of Basic Science Process Skills, digital photography of plate waste, PolarActive accelerometers, anthropometrics, a parent questionnaire, and the School and Community Actions for Nutrition survey. Analysis Evaluation will include quantitative and qualitative measures. Quantitative data will use paired t , chi-square, and Mann-Whitney U tests and regression modeling using P = .05 to determine statistical significance.
This phase 1 clinical trial was conducted to determine the safety, maximum-tolerated dose (MTD), and pharmacokinetics of imatinib, bevacizumab, and metronomic cyclophosphamide in patients with ...advanced colorectal cancer (CRC).
Patients with refractory stage IV CRC were treated with bevacizumab 5 mg kg(-1) i.v. every 2 weeks (fixed dose) plus oral cyclophosphamide q.d. and imatinib q.d. or b.i.d. in 28-day cycles with 3+3 dose escalation. Response was assessed every two cycles. Pharmacokinetics of imatinib and cyclophosphamide and circulating tumour, endothelial, and immune cell subsets were measured.
Thirty-five patients were enrolled. Maximum-tolerated doses were cyclophosphamide 50 mg q.d., imatinib 400 mg q.d., and bevacizumab 5 mg kg(-1) i.v. every 2 weeks. Dose-limiting toxicities (DLTs) included nausea/vomiting, neutropaenia, hyponatraemia, fistula, and haematuria. The DLT window required expansion to 42 days (1.5 cycles) to capture delayed toxicities. Imatinib exposure increased insignificantly after adding cyclophosphamide. Seven patients (20%) experienced stable disease for >6 months. Circulating tumour, endothelial, or immune cells were not associated with progression-free survival.
The combination of metronomic cyclophosphamide, imatinib, and bevacizumab is safe and tolerable without significant drug interactions. A subset of patients experienced prolonged stable disease independent of dose level.
To examine the association between sedentary behavior and cardiometabolic risk, while taking into account cardiorespiratory fitness (fitness) and physical activity.
We examined the association of ...sedentary behavior, physical activity, and fitness (exposure variables) to cardiometabolic biomarkers and metabolic syndrome (outcome measures) among a historic cohort (January 2, 1981, through October 16, 2012) of men. First, we estimated the association (cross-sectionally and longitudinally) of sedentary behavior along with physical activity and fitness to lipids and lipoproteins, glucose, blood pressure, and markers of adiposity, including body mass index, waist circumference, and body fat percentage. We then prospectively examined the effects of baseline sedentary time on the incidence of metabolic syndrome, while adjusting for physical activity, fitness, and other covariates in multivariate models.
Multivariate analysis of baseline data revealed that in comparison with the reference group (≤9 h/wk of sedentary time), more sedentary behavior was significantly associated with a higher triglyceride level, a higher triglycerides-high-density lipoprotein cholesterol ratio, and a higher body mass index, waist circumference, and body fat percentage (P<.05 for trend), after adjusting for physical activity and covariates. When adjusting for fitness and covariates, prolonged sedentary time was only associated with a higher triglyceride-high-density lipoprotein cholesterol ratio (P=.02 for trend). Sedentary time was not associated with the incidence of metabolic syndrome in multivariate models. Longitudinal analyses revealed that a 1-metabolic equivalent increase in fitness was significantly (P<.05) associated with almost all biomarkers when adjusting for sedentary behavior, with little moderation observed.
The association between prolonged sedentary time and cardiometabolic biomarkers is markedly less pronounced when taking fitness into account. Further exploration of the effects of sedentary behavior on cardiometabolic risk is warranted in cohorts with available fitness data. Furthermore, our findings underscore the need to encourage achieving higher fitness levels through meeting physical activity guidelines to decrease disease risk factors.
Background The primary rescue medication to treat acute asthma exacerbation is the short-acting β2 -adrenergic receptor agonist; however, there is variation in how well a patient responds to ...treatment. Although these differences might be due to environmental factors, there is mounting evidence for a genetic contribution to variability in bronchodilator response (BDR). Objective To identify genetic variation associated with bronchodilator drug response in Latino children with asthma. Methods We performed a genome-wide association study (GWAS) for BDR in 1782 Latino children with asthma using standard linear regression, adjusting for genetic ancestry and ethnicity, and performed replication studies in an additional 531 Latinos. We also performed admixture mapping across the genome by testing for an association between local European, African, and Native American ancestry and BDR, adjusting for genomic ancestry and ethnicity. Results We identified 7 genetic variants associated with BDR at a genome-wide significant threshold ( P < 5 × 10−8 ), all of which had frequencies of less than 5%. Furthermore, we observed an excess of small P values driven by rare variants (frequency, <5%) and by variants in the proximity of solute carrier (SLC) genes. Admixture mapping identified 5 significant peaks; fine mapping within these peaks identified 2 rare variants in SLC22A15 as being associated with increased BDR in Mexicans. Quantitative PCR and immunohistochemistry identified SLC22A15 as being expressed in the lung and bronchial epithelial cells. Conclusion Our results suggest that rare variation contributes to individual differences in response to albuterol in Latinos, notably in SLC genes that include membrane transport proteins involved in the transport of endogenous metabolites and xenobiotics. Resequencing in larger, multiethnic population samples and additional functional studies are required to further understand the role of rare variation in BDR.
We observed asteroid (596) Scheila and its ejecta cloud using the Swift UV-optical telescope. We obtained photometry of the nucleus and the ejecta, and for the first time measured the asteroid's ...reflection spectrum between 290 and 500 nm. Our measurements indicate significant reddening at UV wavelengths (13% per 103 A) and a possible broad, unidentified absorption feature around 380 nm. Our measurements indicate that the outburst has not permanently increased the asteroid's brightness. We did not detect any of the gases that are typically associated with either hypervolatile activity thought responsible for cometary outbursts (CO+, CO2 +), or for any volatiles excavated with the dust (OH, NH, CN, C2, C3). We estimate that 6 X 108 kg of dust was released with a high ejection velocity of 57 m s--1 (assuming 1 Delta *mm sized particles). While the asteroid is red in color and the ejecta have the same color as the Sun, we suggest that the dust does not contain any ice. Based on our observations, we conclude that (596) Scheila was most likely impacted by another main belt asteroid less than 100 m in diameter.
Context. Comet 8P/Tuttle is a nearly isotropic comet whose physical properties are poorly known and might be different from those of ecliptic comets owing to their different origin. Two independent ...observations have shown that 8P/Tuttle has a bilobate nucleus. Aims. Our goal is to determine the physical properties of the nucleus (size, shape, thermal inertia, and albedo) and coma (water and dust) of 8P/Tuttle. Methods. We observed the inner coma of 8P/Tuttle with the infrared spectrograph and the infrared camera of the Spitzer Space Telescope. We obtained one spectrum (5–40 μm) on 2 November 2007 and a set of 19 images at 24 μm on 22–23 June 2008 sampling the rotational period of the nucleus. The data were interpreted using thermal models for the nucleus and the dust coma, and we considered two possible shape models of the nucleus derived from Hubble Space Telescope visible and Arecibo radar observations. Results. We favor a model for the nucleus shape that is composed of two contact spheres with respective radii of 2.7 ± 0.1 km and 1.1 ± 0.1 km and a pole orientation with RA = 285 ± 12° and Dec = +20 ± 5°. The thermal inertia of the nucleus lies in the range 0–100 J K−1 m−2 s−1∕2 and the R-band geometric albedo is 0.042 ± 0.008. The water production rate amounts to 1.1 ± 0.2 × 1028 molecules s−1 at 1.6 AU from the Sun pre-perihelion, which corresponds to an active fraction of ≈9%. At the same distance, the ɛfρ quantity amounts to 310 ± 34 cm, and it reaches 325 ± 36 cm at 2.2 AU post-perihelion. The dust grain temperature is estimated to be 258 ± 10 K, which is 37 K higher than the thermal equilibrium temperature at 1.6 AU. This indicates that the dust grains that contribute to the thermal infrared flux have a typical size of ≈10 μm. The dust spectrum exhibits broad emission around 10 μm (1.5σ confidence level) and 18 μm (5σ confidence level) that we attribute to amorphous pyroxene.
Streptococcus pneumoniae strains have exhibited decreasing susceptibility to penicillins and macrolides during the past several years. We reviewed the medical charts of all patients with pneumococcal ...bacteremia who were admitted to a university hospital over a period of 1 year, to identify failures of outpatient therapy. Of 41 patients admitted with pneumococcal bacteremia, 4 had previously taken either azithromycin or clarithromycin for 3-5 days. All 4 had pneumococcal strains that exhibited low-level resistance to macrolide antibiotics. Among pneumococci, low-level resistance to macrolides can lead to clinical failure, and resistance to macrolides should be considered during the selection of empiric therapy for patients with presumed pneumococcal infections.
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