Comparative Effectiveness of Structural versus Regulatory Protein Gene Transfer on Articular Chondrocyte Matrix Gene Expression

OBJECTIVE: The production of extracellular matrix is a necessary component of articular cartilage repair. Gene transfer is a promising method to improve matrix biosynthesis by articular chondrocytes. Gene transfer may employ transgenes encoding regulatory factors that stimulate the production of matrix proteins, or may employ transgenes that encode the proteins themselves. The objective of this study was to determine which of these 2 approaches would be the better choice for further development. We compared these 2 approaches using the transgenes encoding the structural matrix proteins, aggrecan or type II collagen, and the transgene encoding the anabolic factor, insulin-like growth factor I (IGF-I). METHODS: We transfected adult bovine articular chondrocytes with constructs encoding type II collagen, aggrecan, or IGF-I, and measured the expression of type II collagen ( COL2A1) and aggrecan ( ACAN) from their native genes and from their transgenes. RESULTS: IGF-I gene ( IGF1) transfer increased the expression of the native chondrocyte COL2A1 and ACAN genes 2.4 and 2.9 times control, respectively. COL2A1 gene transfer did not significantly increase COL2A1 transcripts, even when the transgene included the genomic COL2A1 regulatory sequences stimulated by chondrogenic growth factors. In contrast, ACAN gene transfer increased ACAN transcripts up to 3.4 times control levels. IGF1, but not ACAN, gene transfer increased aggrecan protein production. CONCLUSION: Taken together, these results suggest that the type II collagen and aggrecan production required for articular cartilage repair will be more effectively achieved by genes that encode anabolic regulatory factors than by genes that encode the matrix molecules themselves

Transformations of Additivity in Measurement Error Models

In many problems one wants to model the relationship between a response Y and a covariate X. Sometimes it is difficult, expensive, or even impossible to observe X directly, but one can instead observe a substitute variable W which is easier to obtain. By far the most common model for the relationship between the actual covariate of interest X and the substitute W is W = X + U, where the variable U represents measurement error. This assumption of additive measurement error may be unreasonable for certain data sets. We propose a new model, namely h(W) = h(X) + U, where h(.) is a monotone transformation function selected from some family H of monotone functions. The idea of the new model is that, in the correct scale, measurement error is additive. We propose two possible transformation families H. One is based of selecting a transformation which makes the within sample mean and standard deviation of replicated W’s uncorrelated. The second is based on selecting the transformation so that the errors (U’s) fit a prespecified distribution. Transformation families used are the parametric power transformations and a cubic spline family. Several data examples are presented to illustrate the methods

The Physics of Galaxy Cluster Outskirts

As the largest virialized structures in the universe, galaxy clusters continue to grow and accrete matter from the cosmic web. Due to the low gas density in the outskirts of clusters, measurements are very challenging, requiring extremely sensitive telescopes across the entire electromagnetic spectrum. Observations using X-rays, the Sunyaev-Zeldovich effect, and weak lensing and galaxy distributions from the optical band, have over the last decade helped to unravel this exciting new frontier of cluster astrophysics, where the infall and virialization of matter takes place. Here, we review the current state of the art in our observational and theoretical understanding of cluster outskirts, and discuss future prospects for exploration using newly planned and proposed observatories.Comment: 56 pages. Review paper. Published in Space Science Review

Interpreting scores on multiple sclerosis-specific patient reported outcome measures (the PRIMUS and U-FIS)

BACKGROUND: The PRIMUS is a Multiple Sclerosis (MS)-specific suite of outcome measures including assessments of QoL (PRIMUS QoL, scored 0-22) and activity limitations (PRIMUS Activities, scored 0-30). The U-FIS is a measure of fatigue impact (scored 0-66). These measures have been fully validated previously using an MS sample with mixed diagnoses. The aim of the present study was to validate the measures further in a specifically Relapse Remitting MS (RRMS) sample and to provide preliminary evidence of the responder definitions (RD; also known as minimal important difference) for these instruments. METHODS: Data were derived from a multi-country efficacy trial of MS patients with assessments at baseline and 12 months. Baseline data were used to assess the internal reliability and validity of the measures. Both anchor-based and distribution-based approaches were employed for estimating RD. Anchor-based estimates were based on published RD values for the EQ-5D and were assessed for those improving and deteriorating separately. Distribution-based estimates were based on standard error of measurement (SEM), change score equivalent to 0.30, and change score equivalent to 0.50, effect sizes (ES). RESULTS: The sample included 911 RRMS patients (67.3% female, age mean (SD) 36.2 (8.4) years, duration of MS mean (SD) 4.8 (5.2) years). Results showed that the PRIMUS and U-FIS had good internal consistency. Appropriate correlations were observed with comparator instruments and both measures were able to distinguish between participants based on Expanded Disability Status Scale scores and time since diagnosis. The anchor-based and distribution-based RD estimates were: PRIMUS Activities range = 1.2-2.3, PRIMUS QoL range = 1.0-2.2, and U-FIS range = 2.4-7.0. CONCLUSIONS: The results show that the PRIMUS and U-FIS are valid instruments for use with RRMS patients. The analyses provide preliminary information on how to interpret scores on the scales. These data will be useful for assessing treatment efficacy and for powering clinical studies. TRIAL REFERENCE NUMBER: ClinicalTrials.gov Identifier NCT00340834

Developing Short-Term Study Abroad Programs: Achieving Successful International Student Experiences

Most business schools in the U.S. are employing various initiatives to “internationalize” their curriculum in order to prepare students to participate more effectively in a globally interconnected business world.  An integral part of these initiatives is to encourage more students to participate in study abroad programs. Though it maybe optimal for students to study abroad for a semester or more, many students do not have the time, resources or confidence to commit to a long-term experience.  Consequently, short-term two to three week study abroad programs (SSA) are often a viable and worth while experiential alternative. Often, the process of developing a short-term study abroad experience can be daunting.  Weuse a case study approach to examine how short-term study programs were initiated, planned, organized and implemented in five countries - Malaysia, Singapore, Chile, Germany and Australia. These programs were led by business faculty, at an AACSB accredited Midwestern University, each of whom also had prior experience in conducting study abroad programs. These faculty leaders provided detailed accounts related to each of the programs. A guide using probing questions was prepared through a triangulation process that included the faculty leaders and an administrator that had reviewed and audited 12 previous short-term study abroad programs. Drawing on actual SSA experiences and outcomes, this paper proposes a SSA framework consisting of planning, marketing, conducting and evaluating stages that can make the study abroad process understandable, efficient and easier to implement

Role of sox9 in growth factor regulation of articular chondrocytes

Chondrogenic polypeptide growth factors influence articular chondrocyte functions that are required for articular cartilage repair. Sox9 is a transcription factor that regulates chondrogenesis, but its role in the growth factor regulation of chondrocyte proliferation and matrix synthesis is poorly understood. We tested the hypotheses that selected chondrogenic growth factors regulate sox9 gene expression and protein production by adult articular chondrocytes and that sox9 modulates the actions of these growth factors. To test these hypotheses, we delivered insulin-like growth factor-I (IGF-I), fibroblast growth factor-2 (FGF-2), bone morphogenetic protein-2 (BMP-2) and/or bone morphogenetic protein-7 (BMP-7), or their respective transgenes to adult bovine articular chondrocytes, and measured changes in sox9 gene expression and protein production. We then knocked down sox9 gene expression with sox9 siRNA, and measured changes in the expression of the genes encoding aggrecan and types I and II collagen, and in the production of glycosaminoglycan, collagen and DNA. We found that FGF-2 or the combination of IGF-I, BMP-2, and BMP-7 increased sox9 gene expression and protein production and that sox9 knockdown modulated growth factor actions in a complex fashion that differed both with growth factors and with chondrocyte function. The data suggest that sox9 mediates the stimulation of matrix production by the combined growth factors and the stimulation of chondrocyte proliferation by FGF-2. The mitogenic effect of the combined growth factors and the catabolic effect of FGF-2 appear to involve sox9-independent mechanisms. Control of these molecular mechanisms may contribute to the treatment of cartilage damage

Sitting and Supine Esophageal Pressures in Overweight and Obese Subjects Authors

Esophageal pressure can be used to approximate pleural pressure and might be clinically useful, particularly in the obese e.g to guide mechanical ventilator settings in critical illness. However, mediastinal artifact (the difference between true pleural pressure and esophageal pressure) may limit acceptance of the measurement, and reproducibility of esophageal pressure measurements remains unknown. Therefore, we aimed to assess the effect of body posture on esophageal pressure in a cohort of obese but healthy subjects, some of whom had multiple measurements, to address the clinical robustness of esophageal manometry. Twenty-five overweight and obese subjects (BMI>25kg/m2) and 11 control lean subjects (BMI<25kg/m2) underwent esophageal manometry with pressures measured seated and supine. Twenty overweight and obese subjects had measurements repeated after ~1-2 weeks. Anthropometric data and sitting and supine spirometry were recorded. The average end-expiratory esophageal pressures sitting and supine were greater in the overweight and obese group than the lean group (sitting −0.1±2.1 vs. −3.3±1.2cmH2O, supine 9.3±3.3 vs. 6.9±2.8cmH2O, respectively). The mean differences between repeated measurements were small (−0.3 ± 1.7cmH2O sitting and −0.1 ± 1.5cmH2O supine). Esophageal pressures correlated with a number of anthropometric and spirometric variables. In conclusion, esophageal pressures are slightly greater in overweight and obese subjects than lean subjects; but changes with position are similar in both groups. These data indicate that mediastinal weight and postural effects on esophageal pressure are within a clinically acceptable range, and suggest that esophageal manometry can be used to inform clinical decision making across wide range of body types

Human IGF-I propeptide A promotes articular chondrocyte biosynthesis and employs glycosylation-dependent heparin binding

Background Insulin-like growth factor I (IGF-I) is a key regulator of chondrogenesis, but its therapeutic application to articular cartilage damage is limited by rapid elimination from the repair site. The human IGF-I gene gives rise to three IGF-I propeptides (proIGF-IA, proIGF-IB and proIGF-IC) that are cleaved to create mature IGF-I. In this study, we elucidate the processing of IGF-I precursors by articular chondrocytes, and test the hypotheses that proIGF-I isoforms bind to heparin and regulate articular chondrocyte biosynthesis. Methods Human IGF-I propeptides and mutants were overexpressed in bovine articular chondrocytes. IGF-I products were characterized by ELISA, western blot and FPLC using a heparin column. The biosynthetic activity of IGF-I products on articular chondrocytes was assayed for DNA and glycosaminoglycan that the cells produced. Results Secreted IGF-I propeptides stimulated articular chondrocyte biosynthetic activity to the same degree as mature IGF-I. Of the three IGF-I propeptides, only one, proIGF-IA, strongly bound to heparin. Interestingly, heparin binding of proIGF-IA depended on N-glycosylation at Asn92 in the EA peptide. To our knowledge, this is the first demonstration that N-glycosylation determines the binding of a heparin-binding protein to heparin. Conclusion The biosynthetic and heparin binding abilities of proIGF-IA, coupled with its generation of IGF-I, suggest that proIGF-IA may have therapeutic value for articular cartilage repair. General significance These data identify human pro-insulin-like growth factor IA as a bifunctional protein. Its combined ability to bind heparin and augment chondrocyte biosynthesis makes it a promising therapeutic agent for cartilage damage due to trauma and osteoarthritis

Kestrel Eye Block II

Kestrel Eye (KE) is a microsatellite technology demonstrator for the US Army Space and Missile Defense Command (USASMDC) / Army Forces Strategic Command (ARSTRAT) developed by Quantum Research International, Inc. and Adcole Maryland Aerospace (AMA). Kestrel Eye weighs approximately 50 kg and provides electro-optical images with tactically useful resolution as requested by the warfighters in theater. The warfighters in theater will task and receive data from the satellite during the same pass overhead. The data can be downlinked directly to provide rapid situational awareness to our Army Brigade Combat Teams in theater without the need for continental United States relays. By using a small satellite, the required logistics footprint in the field is reduced as compared to an Unmanned Aerial System (UAS). In addition, developing a constellation of small satellites increases survivability and provides graceful degradation as no individual satellite is critical to the functioning of the constellation. Once Kestrel Eye reaches production, it will have a relatively low cost at approximately $2 million per spacecraft and will have an operational life of greater than one year in low earth orbit. With its low cost, large numbers of satellites can be procured enabling the system to be dedicated to the tactical warfighter. Kestrel Eye was successfully deployed from the International Space Station on 24 October 2017. The performance of this satellite is now undergoing investigation to validate the specifications of the satellite are met. The checkout investigation is being performed jointly by a ground station in Huntsville, AL operated by USASMDC/ARSTRAT and one in Hawaii operated by United States Pacific Command (USPACOM). At the conclusion of those investigations, the satellite will undergo a series of exercise experiments to evaluate if similar satellites could support critical operations. If the experiments are successful, it is expected satellites of similar capability can be procured/operated at a low cost. This paper provides the background and development of Kestrel Eye as well as a current status of the orbital mission

Vocation Learning Outcomes at the University of Dayton

This working paper summarizes the work of the Habits of Inquiry and Reflection Vocation Fellows. It offers a definition of vocation for use at the University of Dayton, proposes a series of steps the University could take to promote vocational discernment on campus, and identifies challenges the institution must address to achieve that goal