Racial and Ethnic Variations in Preventive Dental Care Utilization among Middle-Aged and Older Americans, 1999-2008.

Objective: This study examined recent trends of preventive dental care utilization among Americans aged 50 and above, focusing on variations across racial and ethnic groups including Whites, Blacks, Hispanics, American Indians/Alaska Natives, and Asians.

Methods: Self-reported information on oral health behaviors was collected from 644,635 participants in the Behavioral Risk Factor Surveillance System between 1999 and 2008.

Results: Despite a significant upward trend of frequency of dental cleaning from 1999 to 2008 (OR = 1.

Efficient introduction of aryl bromide functionality into proteins in vivo.

Artificial proteins can be engineered to exhibit interesting solid state, liquid crystal or interfacial properties and may ultimately serve as important alternatives to conventional polymeric materials. The utility of protein-based materials is limited, however, by the availability of just the 20 amino acids that are normally recognized and utilized by biological systems; many desirable functional groups cannot be incorporated directly into proteins by biosynthetic means. In this study, we incorporate para-bromophenylalanine (p-Br-phe) into a model target protein, mouse dihydrofolate reductase (DHFR), by using a bacterial phenylalanyl-tRNA synthetase (PheRS) variant with relaxed substrate specificity.

Expansion of the genetic code: site-directed p-fluoro-phenylalanine incorporation in Escherichia coli.

Site-directed incorporation of the amino acid analogue p-fluoro-phenylalanine (p-F-Phe) was achieved in Escherichia coli. A yeast suppressor tRNA(Phe)amber/phenylalanyl-tRNA synthetase pair was expressed in an analogue-resistant E. coli strain to direct analogue incorporation at a programmed amber stop codon in the DHFR marker protein.

The in vitro kinetics of mitochondrial and cytosolic creatine kinase determined by saturation transfer 31P-NMR.

Michaelis- and dissociation constants of sarcomeric mitochondrial creatine kinase (Mi(b)-CK) in solution were determined by enzyme assay and compared to those of cytosolic MM-CK under identical conditions at pH 7.4 and 25 degrees C. Saturation transfer 31P-NMR was used to determine the steady state fluxes mediated by Mi-CK and MM-CK in solution.

Reconstitution of active octameric mitochondrial creatine kinase from two genetically engineered fragments.

Creatine kinase (CK) has been postulated to consist of two flexibly hinged domains. A previously demonstrated protease-sensitive site in M-CK (Morris & Jackson, 1991) has directed our attempts to dissect mitochondrial CK (Mi-CK) into two protein fragments encompassing amino acids [1-167] and [168-380]. When expressed separately in Escherichia coli, the two fragments yielded large amounts of insoluble inclusion bodies, from which the respective polypeptides could be purified by a simple two-step procedure.