Faculty Bibliography

Abstract Objectives: Craniosynostosis affects 1 in 2,000-3,000 live births and may result in craniofacial and neural growth disturbances. Histological data have shown that thick collagenous bundles are present in the sutural ligament, which may tether the osteogenic fronts, resulting in premature fusion. The hormone relaxin has been shown to disrupt collagen fiber organization, possibly preventing craniosynostosis by relaxing the sutural ligament and allowing osteogenic fronts to separate normally and stay patent. This study tested this hypothesis in a rabbit model of delayed onset coronal suture synostosis. Methods: 18 New Zealand White rabbits with craniosynostosis were randomly assigned to three groups: Sham control, protein control (BSA), relaxin treatment. After initial diagnosis, sham surgery, BSA, or relaxin were delivered to the fusing coronal suture in a slow release (56 day) collagen vehicle. Longitudinal radiographs and body weights were collected at 10, 25, 42, and 84 days of age and sutures were harvested for histology. Results: Relaxin treated animals had more disorganized intra-suture content than control groups. These specimens also appeared to have relatively wider sutures ectocranially. There were no significant differences in relaxin treated animals for all craniofacial growth measures, or suture separation compared to controls. Conclusions: These data do not support our initial hypothesis that the use of relaxin may rescue sutures destined to undergo premature suture fusion. These findings suggest that collagen fiber arrangement may not be important for suture fusion. This protein therapy would not be clinically useful for craniosynostosis. Key Words: Relaxin, Craniosynostosis, Extracellular Matrix, Collagen Fibers, Cephalometrics

PURPOSE: The purpose of this study was to determine the quantity and quality of DNA extracted from a dental bite impression wafer immediately after impression and after 12 months of home storage. The authors' hypothesis was that the wafer would retain sufficient DNA with appropriate genetic markers to make an identification match. METHODS: Two impression wafers (Toothprints((R)) brand) were administered to 100 3- to 26-year-olds. A cotton swab was used as a control. DNA from wafers stored for 12 months at home were compared to DNA collected at time 0 and compared to swabs at specific sites to determine quality and accuracy. The amount of DNA captured and recovered was analyzed using MagAttract technology and a quantitative real-time polymerase chain reaction. Capillary gel electrophoresis was performed to determine the quality of the DNA profiles obtained from the wafers vs those generated from the swabs of each subject. RESULTS: Average DNA concentration was: 480 pg/muL (wafer at time 0); 392 pg/muL (wafer after 12 months kept by subjects); and 1,041 pg/muL (buccal swab). Sufficient DNA for human identification was recovered from all sets of wafers, producing clear DNA profiles and accurate matches to buccal swabs. No inhibitors were found that could interfere with DNA profiling. CONCLUSIONS: Toothprints(R) impression wafers can be useful for DNA collection and child identification. After 12 months, the wafer was still usable for DNA capture and identification match.

A piano concert series and jazz reception program was organized at the College of Dentistry at New York University, in 2007. An anonymous survey to assess the response of faculty, staff, and students to the concert series was conducted during 2010 to 2011. Overwhelmingly, the respondents recommend that music concerts in the dental college be continued. Support is apparent in the overall recommendation and in questions dealing with stress, productivity, music, the auditorium, and the community. Differences between groups defined by status (student, faculty, other, or unknown) and by previous music study (yes, no, or unknown) were small. Events such as a concert series organized at the College of Dentistry apparently can have positive influence on work-life balance.

The introduction of mobile electronic devices, as opposed to paper forms, in pediatric outreach programs of the New York University College of Dentistry is discussed. Since 2007, students have been receiving training on how to operate a personal digital assistant (PDA) and use it in community outreach for non-invasive oral-facial screenings and patient education. The shift from using paper forms to electronic media had a positive impact among the academic community, as it resulted in saving time and reducing the possibility of data collection errors. It may represent a significant improvement in data collection and patient education; and it provides an opportunity to enhance research and quality assessment.

The HIV-1 Tat peptide has been successfully used for intracellular gene delivery. Likewise, various lipid-based methods have shown increased endocytosis and can influence endosomal escape. This study combines the favorable properties of Tat peptide with that of lipid systems for DNA delivery. We combined the lipid FuGENE HD (FH) with the Tat peptide sequence modified with histidine and cysteine residues (mTat). mTat/FH transfection was evaluated by luciferase expression plasmid in five cell types. mTat/FH produced significant improvement in transfection efficiency of all cell lines when compared to FH or mTat. Treatment with chloroquine, associated with energy-dependent endocytosis, significantly increased transfection efficiency with mTat/FH while incubation at low temperature decreased it. The zeta potential of mTat/FH/DNA was significantly higher compared to FH, mTat, or their DNA combination in the presence of serum, and it was correlated with transfection efficiency. The particle size of the FH/DNA complex was significantly reduced by addition of mTat. Filipin III, an inhibitor of caveolae-mediated endocytosis, significantly inhibited mTat/FH transfection, but transfection was increased by chlorpromazine, an inhibitor of clathrin-mediated endocytosis. These findings demonstrated the feasibility of using a combination of mTat with lipids, utilizing temperature-dependent and caveolae-mediated endocytosis, as a potentially attractive non-viral gene vector

BACKGROUND:: Craniosynostosis is defined as the premature fusion of one or more cranial sutures. Bone morphogenetic proteins (BMPs), regulators of ossification, have been implicated in premature suture fusion. Noggin, an extracellular BMP inhibitor, has been shown experimentally to inhibit resynostosis following surgery. The present study was designed to test the hypothesis that BMP inhibition using noggin therapy may rescue sutures destined to fuse by inhibiting initial ossification. METHODS:: Twenty-six, 10-day old rabbits with familial, delayed-onset, coronal suture synostosis were randomly divided into three groups: (1) the sham surgical control group, (2) the bovine serum albumin-treated group [10 mug/suture (protein/vehicle controls)], and (3) the noggin therapy group (10 mug/suture; experimental group). Sutural growth was monitored by radiopaque markers implanted at 10 days of age. At 25 days, the bovine serum albumin or noggin was combined with a slow-resorbing collagen vehicle and injected subperiosteally above the coronal suture. Somatic and sutural growth data were collected at 10, 25, 42, and 84 days of age. Coronal sutures were harvested at 84 days to histologically assess fusion. RESULTS:: Results showed no significant (p > 0.05) differences in suture separation at any age. Suture fusion assessed by histomorphology did not differ among the three groups. Although previous data showed noggin to inhibit postoperative resynostosis in this craniosynostotic rabbit model, here there was no effect on initial suture fusion. CONCLUSION:: These results suggest that in this rabbit model of craniosynostosis, BMPs do not play a role in the pathogenesis of craniosynostosis and only play a role in postoperative bony wound healing