Search PubMed⌕ Search

Biomedical subjects

J Kleinberg

Publications and source records attributed to J Kleinberg.

6 recordsLinked to original sources
PubMed1983

Effects of deinstitutionalization on adaptive behavior of mentally retarded adults.

Twenty mentally retarded clients were moved from a large developmental center to three small community residences. Their functional abilities were measured at 0, 4, 8, and 12 months. Consistent improvement was found for language development, domestic activity, responsibility, and social interaction. Findings from this and other "deinstitutionalization" studies were synthesized. Results suggested that the improvement in functioning represents a manifestation of behavior already in the clients' repertoire rather than new learning. The need for systematic programming to promote learning, both in the community and institution, was emphasized.

Adolescent↗
PubMed1979

Intraocular penetration of topically applied lincomycin hydrochloride in rabbits.

Ocular penetration of lincomycin hydrochloride in albino rabbits was determined by bioassay. On topical application, the frequency of multiple instillation of drops played an important role in producing therapeutic levels in the anterior chambers. Therapeutic levels were attained in the cornea, aqueous humor, and iris-ciliary body, with peak values occurring at 30 to 45 minutes. Varying the pH of the dosing solution did not change ocular absorption and distribution substantially. Removal of corneal epithelium, however, greatly enhanced absorption. Relative to clindamycin, lincomycin hydrochloride had longer onset of peak values and lower overall concentration in ocular tissues. Intravitreous injection of lincomycin hydrochloride produced therapeutic and steady levels of antibiotic in anterior chambers. Injection produced a concentration in aqueous humor twice that achievable topically. The major route of elimination from the posterior chamber was through retina-choroid.

Administration, Topical↗
PubMedDate not supplied

Fast detection of common geometric substructure in proteins.

We consider the problem of identifying common three-dimensional substructures between proteins. Our method is based on comparing the shape of the alpha-carbon backbone structures of the proteins in order to find three-dimensional (3D) rigid motions that bring portions of the geometric structures into correspondence. We propose a geometric representation of protein backbone chains that is compact yet allows for similarity measures that are robust against noise and outliers. This representation encodes the structure of the backbone as a sequence of unit vectors, defined by each adjacent pair of alpha-carbons. We then define a measure of the similarity of two protein structures based on the root mean squared (RMS) distance between corresponding orientation vectors of the two proteins. Our measure has several advantages over measures that are commonly used for comparing protein shapes, such as the minimum RMS distance between the 3D positions of corresponding atoms in two proteins. A key advantage is that this new measure behaves well for identifying common substructures, in contrast with position-based measures where the nonmatching portions of the structure dominate the measure. At the same time, it avoids the quadratic space and computational difficulties associated with methods based on distance matrices and contact maps. We show applications of our approach to detecting common contiguous substructures in pairs of proteins, as well as the more difficult problem of identifying common protein domains (i.e., larger substructures that are not necessarily contiguous along the protein chain).

Algorithms↗