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Biomedical subjects

J C Webster

Publications and source records attributed to J C Webster.

At least 37 records · Page 2Linked to original sources
PubMed1986

Changes in glycoprotein carbohydrate content in the aging human brain.

There is no significant change in the concentration, per gram of fresh tissue, of the total carbohydrate associated with brain glycoproteins as the human brain ages from 25 to 85 years. Nevertheless, notable shifts in the concentration of varied types of oligosaccharides do occur. The concentration and percentage of total glycopeptide-carbohydrate recovered from the whole brain represented by the N-glycosidically linked complex sialooligosaccharides of the tri- and tetraantennary type show a marked decline with age. On the other hand, the N-linked mannose high oligosaccharides of the ovalbumin type, the N-linked biantennary sialoglycopeptides of the transferrin type, and the O-linked oligosaccharides show an increase as the brain ages. Other age related changes that were noted include an increase in the number of sulfate ester groups associated with the N-linked sialoglycopeptides and a decrease in the number of phosphorylated high mannose oligosaccharides as the brain ages.

Adult↗
PubMed1984

Interlist equivalencies for a numeral and a vowel/consonant multiple-choice monosyllabic test for severely/profoundly deaf young adults.

Conventional multiple-choice speech tests measuring discrimination of initial/final consonants, and the CID "Everyday" Sentences test are too difficult for many young adults whose hearing is severely/profoundly limited. Using the 6-choice closed-set paradigm, a new 12-item Numerals test was developed as well as a modification of the Pickett et al (Gallaudet) modified rhyme test of vowel and consonantal discrimination. This test, here called the Webster-Pickett (W/P) test, essentially expands the original 2 alternative lists to 6, with some further minor changes. Both these tests were administered to 35 students at the National Technical Institute for the Deaf (NTID). In combination, the new tests provided usable scores for the NTID population. Most of those who yielded scores of zero on the W-22, on the CID sentences tests and on the W/P test nevertheless scored above zero on Numerals, while those who scored 100% on Numerals scored between 0 and 100% on the W/P test. All 6 recorded lists of the Numerals test were equivalent. Slight corrections to those raw scores between 10 and 90% on the 6 lists of the W/P were proposed to yield interlist equivalence.

Deafness↗
PubMed1983

Changes in the concentration and composition of human brain gangliosides with aging.

Ganglioside content and composition were studied in whole brains from 9 neurologically normal male individuals ranging from 25 to 85 years in age. The content of ganglioside-bound sialic acid decreased from 1,070 to 380 micrograms/g fresh tissue at 85 years. Ten individual ganglioside fractions were identified on high-performance thin-layer chromatography, seven of which were quantified. With age, ganglioside composition shifted to a more polar pattern due to an increase in the relative concentration of the more polar fractions GQ1b, GT1b and GD1b and a decrease in GD1a and GM1. Except for GQ1b, the absolute concentration of all gangliosides decreased with age. All changes were more pronounced in younger ages. Results are discussed in relation to structural changes occurring in the aging brain, and the involvement of gangliosides is suggested.

Adult↗
PubMed1980

Synaptic junctional glycoconjugates from chick brain. Glycoprotein identification and carbohydrate composition.

Forebrains from day-old chicks were homogenized and fractionated by differential sedimentation and density gradient centrifugation to yield subcellular fractions. The synaptosomal plasma membrane fraction was further treated with Triton X-100 to yield subsynaptic membrane fractions including synaptic junctions. Glycoproteins from these subsynaptic membrane fractions were identified after separation by SDS-polyacrylamide gel electrophoresis by incubating the gel slabs with radioiodinated concanavalin A. Two lectin-binding proteins were discerned in the synaptic junction fraction while none were observed in the Triton-soluble portion of the synaptic plasma membrane. The carbohydrate content of the glycoproteins from each subcellular fraction was quantitated after methanolysis and derivatization as o-methyl-trifluoroacetyl analogs by gas-liquid chromatography. The lowest concentration of glycoprotein sugars was found in the synaptic junction, mitochondrial, and soluble fractions while the greatest concentration was found in the myelin, light-synaptic plasma membrane, and the Triton-soluble portion of the synaptic plasma membrane. Of the subcellular fractions, the synaptic junction contained the highest porportion of mannose and lowest proportion of sialic acid. Moreover, this fraction's content of galactose and N-acetylglucosamine, relative to mannose was the lowest while its content of fucose was low. The oligosaccharide chains extending into the synaptic cleft therefore are predominantly of the "neutral, mannose-rich" type and are attached to a limited number of high-molecular-weight glycoproteins.

Animals↗
PubMed1980

Recreational activities of lower extremity amputees: a survey.

This study summarizes a detailed questionnaire evaluation of recreational activities participated in by 100 persons with lower extremity amputations. Additional information was obtained from prosthetists and physical therapists. Approximately 60% of the respondents are active in sports. Younger persons of either sex, who have had amputations for congenital deformities or trauma, are most active. Level of amputation does not appear to be a determining factor as to whether amputees participated or not. The most common recreational activities are fishing and swimming. Sports causing the amputee most discomfort are hunting and jogging. The ability to run and jump is the most difficult to achieve. Reasons for non-participation are pain, embarrassment, insufficient training and lack of organized sports programs for the disabled. Fear of further injury or an overprotective family are not inhibiting factors, nor is cost of the prosthesis. Only a few people wear specifically designed recreational prostheses, and only one-third of the amputees believe that their prosthetist is knowledgeable about recreational prostheses, while 40% feel the prosthetist discouraged their own ideas about prosthetic innovations. Therapists also proved inadequate in their knowledge and efforts at preparing the amputee for recreation. The amputees indicate a need for improved prosthetic design, and believe that insufficient information, both verbal and written, was given to them.

Adult↗
PubMed1979

Isolation of synaptic junction-enriched fraction from the forebrain of day-old chickens. Preparation and characterization of chick forebrain subcellular fractions.

Synaptosomal plasma membrane (SPM) and other subcellular fractions were isolated from the forebrain of 1-day-old chickens by a procedure based on that of Davis and Bloom (16) and Cotman and Taylor (13). The procedure involves the centrifugation through a discontinuous sucrose gradient of a crude synaptosomal-mitochondrial fraction which has been lysed and weighed with iodonitrotetrazolium. SPM isolated by this method contains only small amounts of lysosomal or mitochondrial membranes and is practically devoid of contaminating microsomal membranes, as estimated by enzyme marker assays. The purity of chick-brain SPM prepared by this method is compared to the purity of chick-brain fractions obtained by two other laboratories, using different methods (4, 59). The SPM were extracted with Triton X-100 and all fractions solubilized in sodium dodecyl sulfate (sds). The delipidated proteins of all fractions were subjected to SDS-polyacrylamide electrophoresis on slab gels and stained for protein. A distinct difference was observed between the patterns given by the Triton-soluble and -insoluble fractions. Electron microscopy of the synaptic junction fraction showed numerous junctional complexes.

Animals↗
PubMed1978

Ear disease in relation to age in the cleft palate child and adolescent.

Ninety-eight cleft palate subjects were studied to ascertain the eventual adolescent and adult hearing. There were 72 complete clefts of lip and palate and 26 clefts of the palate alone. The incidence or side of ear disease did not appear to be influenced by this type of cleft. Other systemic anomalies were present in 11 cases with congenital middle ear abnormalities in 3 and sensory neural hearing loss in 8 subjects. Progressive improvement in incidence of hearing loss from 94% at 4 years to 42% at 20 years was noted with the strict definition of hearing loss as 10 dB conductive loss at any one frequency. 10% of ears were left with permanent structural changes in the middle ear. In only 2 patients was there a bilateral hearing loss of 20 dB or more through the speech range.

Adolescent↗