Objective To determine the in vivo biocompatibility of septal neocartilage constructs developed in vitro by an alginate intermediate step. Study Design Prospective, animal model. Setting Research laboratory. Subjects and Methods A murine model was used to examine the maturation of neocartilage constructs in vivo. Chondrocytes collected from patients undergoing septoplasty were expanded in monolayer and suspended in alginate beads for three-dimensional culture in media containing human serum and growth factors. After in vitro incubation for 5 weeks, the constructs were implanted in the dorsum of athymic mice for 30 and 60 days (n=9). After the mice were sacrificed, the constructs were recovered for assessment of their morphological, histochemical, biochemical, and biomechanical properties. Results The mice survived and tolerated the implants well. Infection and extrusion were not observed. Neocartilage constructs maintained their general shape and size, and demonstrated cell viability after implantation. The implanted constructs were firm and opaque, sharing closer semblance to native septal tissue relative to the gelatinous, translucent pre-implant constructs. Histochemical staining with hematoxylin and eosin (H&E) revealed that the constructs exhibited distinct morphologies characteristic of native tissue, which were not observed in pre-implant constructs. DNA and type II collagen increased with duration of implantation, whereas type I collagen and glycoaminoglycans (GAG) decreased. Mechanical testing of a 60-day implanted construct demonstrated characteristics similar to native human septal cartilage. Conclusions Neocartilage constructs are viable in an in vivo murine model. The histologic, biochemical, and biomechanical features of implanted constructs closely resemble native septal tissue when compared to pre-implant constructs.

Objectives 1) To localize quantitatively the major biochemical constituents of native adult human septal cartilage across whole septa. Study Design Prospective, basic science Methods The nasal septa from seven cadavers were partitioned into 24 separate regions: six from caudal to cephalic and 4 from dorsal to ventral. Biochemical assays were used to determine the quantities, relative to wet weight, of the major constituents of cartilage: chondrocytes, collagen and sulfated glycosaminoglycan. Results On average, each milligram of wet cartilage contained 24,900 cells, 73.9 micrograms collagen, and 17.1 micrograms sulfated glycosaminoglycan. Cell number showed no significant variation across the septa. In contrast, the caudal regions of the septa were associated with higher levels of collagen, the ventral regions correlated with higher levels of sulfated glycosaminoglycan, and the dorsal regions were associated with an elevated ratio of collagen to sulfated glycosaminoglycan. Conclusion This study represents the first characterization of the biochemical composition of native human septal cartilage across whole septa. Quantities of collagen and sulfated glycosaminoglycan showed region-specific variation across the septum. The localized pattern of collagen and sulfated glycosaminoglycan deposition are consistent with the significance of preserving the “L-strut” during rhinoplasty and other nasal reconstructive procedures. In addition, it may assist in defining design goals for tissue-engineered septal neocartilage constructs to meet specific reconstructive needs in the future. Level of Evidence N/A

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The mAb lan3-6 recognizes a cytosolic antigen which is selectively expressed in the growth cones and axons of a small subset of peripheral sensory neurons fasciculating in a single tract common to all hirudinid leeches. We have used this antibody to clone a novel EF-hand calcium-binding protein, calsensin, by screening an expression vector library. A full-length clone of 1.1 kb identified by the antibody was isolated and sequenced. In situ hybridizations with calsensin probes and antibody staining using new polyclonal antisera generated against calsensin sequence demonstrate that calsensin indeed corresponds to the lan3-6 antigen. Calsensin consists of 83 residues with a calculated molecular mass of 9.1 kD that contains two helix-loop-helix 1. Abbreviations used in this paper: aa, amino acids; CNS, central nervous system; HLH, helix-loop-helix; nt, nucleotide.

Adults automatically adjust their speech and actions in a way that may facilitate infants’ processing (e.g., Brand, Baldwin, & Ashburn, 2002). This research examined whether mothers’ use of repetition for infants depended on whether the object being demonstrated required a series of actions in sequence in order to reach a salient goal (called an “enabling” sequence). Mothers (n = 39) demonstrated six objects, three with an enabling sequence and three with an arbitrary sequence, to their 6- to 8- or 11- to 13-month-olds. As predicted, in demonstrations of objects with an enabling sequence, mothers were more likely to repeatseriesof actions, whereas for those without such structure, mothers were more likely to repeatindividual unitsof action. This may or may not have been deliberately pedagogical on mothers’ part, but nevertheless indicates another way in which input to infants is richly patterned to support their learning.