Efficient Muscle Regeneration by Human PSC-Derived CD82+ ERBB3+ NGFR+ Skeletal Myogenic Progenitors

Differentiation of pluripotent stem cells (PSCs) is a promising approach to obtaining large quantities of skeletal myogenic progenitors for disease modeling and cell-based therapy. However, generating skeletal myogenic cells with high regenerative potential is still challenging. We recently reported that skeletal myogenic progenitors generated from mouse PSC-derived teratomas possess robust regenerative potency. We have also found that teratomas derived from human PSCs contain a skeletal myogenic population. Here, we showed that these human PSC-derived skeletal myogenic progenitors had exceptional engraftability. A combination of cell surface markers, CD82, ERBB3, and NGFR enabled efficient purification of skeletal myogenic progenitors. These cells expressed PAX7 and were able to differentiate into MHC+ multinucleated myotubes. We further discovered that these cells are expandable in vitro. Upon transplantation, the expanded cells formed new dystrophin⁺ fibers that reconstituted almost ¾ of the total muscle volume, and repopulated the muscle stem cell pool. Our study, therefore, demonstrates the possibility of producing large quantities of engraftable skeletal myogenic cells from human PSCs.

In vitro expanded skeletal myogenic progenitors from pluripotent stem cell-derived teratomas have high engraftment capacity

One major challenge in realizing cell-based therapy for treating muscle-wasting disorders is the difficulty in obtaining therapeutically meaningful amounts of engraftable cells. We have previously described a method to generate skeletal myogenic progenitors with exceptional engraftability from pluripotent stem cells via teratoma formation. Here, we show that these cells are functionally expandable in vitro while retaining their in vivo regenerative potential. Within 37 days in culture, teratoma-derived skeletal myogenic progenitors were expandable to a billion-fold. Similar to their freshly sorted counterparts, the expanded cells expressed PAX7 and were capable of forming multinucleated myotubes in vitro. Importantly, these cells remained highly regenerative in vivo. Upon transplantation, the expanded cells formed new DYSTROPHIN⁺ fibers that reconstituted up to 40% of tibialis anterior muscle volume and repopulated the muscle stem cell pool. Our study thereby demonstrates the possibility of producing large quantities of engraftable skeletal myogenic cells for transplantation.

Statutory classification of cocaine as a narcotic: an illogical anachronism

Although cocaine is pharmacologically not a narcotic, federal and state drug control laws have classified it as one from 1922 through the present. In many states and under federal law, the classification is part of a statutory scheme that imposes substantially more severe penalties for offenses involving cocaine than for offenses involving other nonnarcotic drugs. This Note examines the circumstances surrounding the adoption and maintenance of the legal classification of cocaine as a narcotic. It then reviews two of the many cases that have rejected claims that the classification is unconstitutional. The Note concludes that, despite its constitutionality, the inaccurate classification is not only illogical and unnecessary to a legislative goal of strictly penalizing cocaine offenses, but is counterproductive as well.

The Multidimensional Scaling Of A Set Of Artistic Drawings : Perceived Structure And Scale Correlates

Product-centered research on creativity approaches the criterion problem of what is to be the referent for creativity through the analysis of tangible products such as a r t objects, writing, or scientific achievements. The present research is concerned with the evaluation and study of artist drawings contributed by sophomore students a t the Rhode Island School of Design. Multi-dimensional scaling methods were applied to similarity judgments obtained from art experts on two separate sets of 26 drawings. Three similarity dimensions accounted for the interstimulus distances for each set of drawings. Although no statistical test was available, the dimensions from the two seta appeared to correspond. Scale values of 4 drawings common to the two sets were consistent, and the dimensions appeared to define very similar stimulus characteristics. It was concluded that multidimensional scaling procedures provided a means for differentiating among a set of complex, esthetic products. Scale values of drawings on the three dimensions also correlated differentially with cognitive and achievement measures available on the students, suggesting that product dimensions identified via similarity judgments were related to characteristics of individuals producing the products. Hypotheses were developed as to the psychological meaning of the three product dimensions.

Points of view about preference as tools in the analysis of creative products

Research on the creative product may provide an analytical tool for generating and testing hypotheses about psychological variables related to level and style of creative achievement. Evaluations of products should be analyzed to determine (1) whether more than one point of view about quality is held among a heterogeneous group of judges and (2) whether personality, academic, and background characteristics of Ss producing the products relate differentially to quality as defined by different points of view. In a study of artistic creativity, drawings were collected from 191 sophomore students at a school of design and rated for esthetic quality by 28 artist and non-artist judges. Four points of view about quality were identified by factor analysis of correlations between judges. Evidence is presented that psychological, achievement, and background characteristics of Ss are differentially related to quality of their drawings as defined by the four points of view. In particular, choice of major, scores on certain aptitude tests, academic performance in the fine arts courses, and measures of wealth of cultural background showed differential correlations with the points of view. Finally, characteristics of drawings rated high or low according to at least two of the judgmental viewpoints may be useful in the generation of hypotheses about psychological variables related to creativity.

Paleontologic Investigations at Big Bone Lick State Park, Kentucky: A Preliminary Report

The Big Bone Lick area in Kentucky, the first widely known collecting locality for vertebrate fossils in North America, is being investigated for further faunal and geologic evidence. Mammal bones, ranging in age from Wisconsin (Tazewell?) to Recent, were recovered in 1962 from four different faunal zones in two terrace fills.