Faculty Bibliography

Health care, including oral health care and oral health education, is under great stress in the United States. The cost of and access to care, the cost of dental education, and a shortage of educators have led leaders in dental education, organized dentistry, and the public sector to underscore the problem. One of the proposed solutions is to find synergies and new health care and education models by building bridges among the health professions. One potential solution is being implemented at the NYU College of Dentistry (NYUCD). Dentistry and nursing are seemingly unrelated professions, and they are rarely if ever modeled together. That is about to change with the joining together of NYUCD and the Division of Nursing of the NYU Steinhardt School of Education in creating a College of Nursing within the College of Dentistry. This process has not been without controversy. Following the Division of Nursing's request to join NYUCD, and the subsequent announcement of the proposed combination by NYU in December 2004, some members of the dental profession responded by questioning the appropriateness of the merger and the similarity of the two programs. Nevertheless, substantial parallels exist in the education and practice of dentists and nurse practitioners (NP) including basic, social, and some clinical science education, practice models, research synergies, and community service. However, similarities in the core competencies of these professions have not been analyzed formally and in detail. Accordingly, the purpose of this study was to compare the core competencies of nurse practitioner and dental education programs. The results show a surprising overlap of the core competencies of the dental and nursing professions (38 percent partial or total overlap). A similar overlap with medicine also exists, albeit lower (25.4 percent). These results are notable because they demonstrate that the three health professions, independently of one another, developed very similar basic competencies and learning objectives. These data should encourage other health professions programs to seek new collaborative models for education, beyond the current silos of training, and new health care delivery systems as has been strongly recommended by the Institute of Medicine. Such collaborative education redirects health care toward providing truly interdisciplinary comprehensive primary care for patients.

BACKGROUND: The channel catfish, Ictalurus punctatus, is invested with a high density of cutaneous taste receptors, particularly on the barbel appendages. Many of these receptors are sensitive to selected amino acids, one of these being a receptor for L-arginine (L-Arg). Previous neurophysiological and biophysical studies suggested that this taste receptor is coupled directly to a cation channel and behaves as a ligand-gated ion channel receptor (LGICR). Earlier studies demonstrated that two lectins, Ricinus communis agglutinin I (RCA-I) and Phaseolus vulgaris Erythroagglutinin (PHA-E), inhibited the binding of L-Arg to its presumed receptor sites, and that PHA-E inhibited the L-Arg-stimulated ion conductance of barbel membranes reconstituted into lipid bilayers. RESULTS: Both PHA-E and RCA-I almost exclusively labeled an 82-84 kDa protein band of an SDS-PAGE of solubilized barbel taste epithelial membranes. Further, both rhodamine-conjugated RCA-I and polyclonal antibodies raised to the 82-84 kDa electroeluted peptides labeled the apical region of catfish taste buds. Because of the specificity shown by RCA-I, lectin affinity was chosen as the first of a three-step procedure designed to enrich the presumed LGICR for L-Arg. Purified and CHAPS-solubilized taste epithelial membrane proteins were subjected successively to (1), lectin (RCA-I) affinity; (2), gel filtration (Sephacryl S-300HR); and (3), ion exchange chromatography. All fractions from each chromatography step were evaluated for L-Arg-induced ion channel activity by reconstituting each fraction into a lipid bilayer. Active fractions demonstrated L-Arg-induced channel activity that was inhibited by D-arginine (D-Arg) with kinetics nearly identical to those reported earlier for L-Arg-stimulated ion channels of native barbel membranes reconstituted into lipid bilayers. After the final enrichment step, SDS-PAGE of the active ion channel protein fraction revealed a single band at 82-84 kDa which may be interpreted as a component of a multimeric receptor/channel complex. CONCLUSIONS: The data are consistent with the supposition that the L-Arg receptor is a LGICR. This taste receptor remains active during biochemical enrichment procedures. This is the first report of enrichment of an active LGICR from the taste system of vertebrata

Various genes related to early events in human gustation have recently been discovered, yet a thorough understanding of taste transduction is hampered by gaps in our knowledge of the signaling chain. As a first step toward gaining additional insight, the expression specificity of genes in human taste tissue needs to be determined. To this end, a fungiform papillae cDNA library has been generated and analyzed. For validation of the library, taste-related gene probes were used to detect known molecules. Subsequently, DNA sequence analysis was performed to identify further candidates. Of 987 clones sequenced, clustering results in 288 contigs. Comparison of these contigs with genomic databases reveals that 207 contigs (71.9%) match known genes, 16 (5.6%) match hypothetical genes, eight (2.8%) match repetitive sequences and 57 (19.8%) have no or low similarity to annotated genes. The results indicate that despite a high level of redundancy, this human fungiform cDNA library contains specific taste markers and is valuable for investigation of both known and novel taste-related genes

PURPOSE: To determine both the efficacy and safety of the topical application of 50 mg penicillin G potassium troches (Cankercillin) in the treatment of minor recurrent aphthous stomatitis (RAS). STUDY DESIGN: The investigation used a phase 2 double-blind, randomized placebo-controlled trial with a no-treatment arm. Subjects with minor aphthous ulcers of duration <48 hours were followed for 1 week. The primary endpoint for efficacy was time (days) to complete ulcer resolution, and the secondary endpoint was time (days) to complete pain relief. RESULTS: Thirty-one, 33, and 36 subjects were randomized to the active treatment, placebo, and no-treatment arms, respectively. Baseline findings were heterogeneous across arms. Subjects who received penicillin G treatment had complete ulcer healing and pain relief significantly earlier than those in the placebo and no-treatment arms. No allergic reactions were observed. CONCLUSIONS: Topical penicillin G, by mechanisms which remain unclear, reduces the time of healing and pain relief of minor aphthous ulcers with minimal safety concerns. Larger phase 3 studies are necessary to confirm these findings

The sweeteners saccharin, D-tryptophan, and neohesperidin dihydrochalcone (NHD) and the bitter tastant cyclo(Leu-Trp) stimulated concentration-dependent pigment aggregation in a Xenopus laevis melanophore cell line similar to melatonin. Like melatonin, these tastants inhibited (by 45-92%) cAMP formation in melanophores; pertussis toxin pretreatment almost completely abolished the tastant-induced cAMP inhibition, suggesting the involvement of the inhibitory pathway (Gi) of adenylyl cyclase. The presence of luzindole (melatonin receptor antagonist) almost completely abolished the inhibition of cAMP formation induced by saccharin, D-tryptophan, and cyclo(Leu-Trp) but only slightly affected the inhibitory effect of NHD. In contrast, the presence of an alpha2-adrenergic receptor antagonist, yohimbine, almost completely abolished the inhibition of cAMP formation induced by NHD but had only a minor effect on that induced by the other tastants. Thus saccharin, D-tryptophan, and cyclo(Leu-Trp) are melatonin receptor agonists whereas NHD is an alpha2-adrenergic receptor agonist, but both pathways lead to the same transduction output and cellular response. Formation of D-myo-inositol 1,4,5-trisphosphate (IP3) in melanophores was reduced (15-58%, no concentration dependence) by saccharin, D-tryptophan, and cyclo(Leu-Trp) stimulation but increased by NHD stimulation. Tastant stimulation did not affect cGMP. Although some of the above tastants were found to be membrane permeant, their direct activation of downstream transduction components in this experimental system is questionable. MT1 and MT2 melatonin receptor mRNAs were identified in rat circumvallate papilla taste buds and nonsensory epithelium, suggesting the occurrence of MT1 and MT2 receptors in these tissues. Melatonin stimulation reduced the cellular content of cAMP in taste cells, which may or may not be related to taste sensation

Human submandibular/sublingual saliva contains a protein that promotes adhesion of Streptococcus mutans JBP serotype-c to spheroidal hydroxyapatite in vitro. A high molecular-weight (250,000-300,000 Da) adhesion-promoting protein (APP) was purified by Trisacryl 2000 M gel-filtration chromatography and gel electroelution before it was partially characterized. Lectin blotting identified that the terminal carbohydrates include N-acetyl glucosamine-beta 1-4-N-acetylglucosamine, galactose and galactose-beta 1-3-N-acetyl galactosamine. Antibodies to APP demonstrated no difference in the immunoreactive pattern of APP from saliva of caries-active or caries-resistant individuals belonging to four different ethnic groups: Asian, African-American, Hispanic or Caucasian. No immunological similarities to salivary mucins or parotid agglutinins were detected by Western blotting using immuno-cross-reactivity as a criterion. APP appears to be a unique protein found in submandibular/sublingual saliva. Understanding such a protein could help prevent S. mutans attachment to the enamel surface

Signal messengers such as cAMP, IP3 and cGMP in taste cells following bitter and sweet taste stimulation can be monitored in real time, in the subsecond range. However, many amphipathic sweeteners and bitter tastants are slow in taste onset and linger, and the molecular basis for these temporal properties is ill-defined. The bitter tastants quinine and cyclo(Leu-Trp), and the non-sugar sweetener saccharin, permeate rapidly through liposomes and taste cells. Furthermore, amphipathic bitter tastants appear to interact with and/or permeate phospholipid-based bitter taste inhibitors. Thus, bitter taste is masked by preventing access of these tastants to taste cells. Such tastants can stimulate responses in cells that are not related to taste cells, and are therefore unlikely to contain taste receptors. It is hypothesized that due to their rapid permeation into taste cells, these tastants may activate the downstream transduction components directly, in addition to their action on G-protein-coupled receptors. The delayed temporal properties produced by many bitter tastants and non-sugar sweeteners may be related to this phenomenon