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Biomedical subjects

L Boyd

Publications and source records attributed to L Boyd.

30 records · Page 2Linked to original sources
PubMed1987

Disinfection of metal and plastic pelvic specula in general practice.

One hundred and sixteen general practices in Wellington were surveyed about their use and disinfection of gynaecological specula. Two thirds of the practices used metal specula which were adequately disinfected by boiling for at least one hour. Of the 46 practices that used plastic specula, only four always disposed of them, as recommended, after use. Aldehyde or halogen disinfectants which are effective against all important sexually-transmitted disease (STD) organisms were used by only 13 of the 42 practices that recycled specula. The remaining 29 practices used quaternary ammonium or diguanide disinfectants which may not be effective against all STD organisms.

Disinfection↗
PubMed1986

Analysis of hybrid H-2D and L antigens with reciprocally mismatched aminoterminal domains: functional T cell recognition requires preservation of fine structural determinants.

Studies of immune recognition of hybrid class I antigens expressed on transfected cells have revealed an apparent general requirement that the N(alpha 1) and C1(alpha 2) domains be derived from the same gene in order to preserve recognition by virus-specific H-2-restricted and allospecific T cells. One exception has been the hybrid DL antigen in which the N domain of H-2Ld has been replaced by that of H-2Dd. Cells bearing this molecule serve as targets for some virus and allospecific CTL. Because cells expressing the reciprocal hybrid LD (N domain of H-2Dd replaced by that of H-2Ld) antigen have not been available, it has not been possible to evaluate whether this exception stemmed from the relatedness of H-2Ld and H-2Dd or whether the DL antigen fortuitously preserved some function of the parent molecule as a rare exception. To assess this question, and to evaluate the contribution of the N and C1 domains of H-2Ld and H-2Dd to serologic and T cell recognition, we have constructed the reciprocal chimeric gene pLD (the N exon of H-2Ld substituted for that of H-2Dd), introduced this into mouse L cells by DNA-mediated gene transfer, and analyzed the expressed product biochemically, serologically, and functionally. Transformant L cells expressing either LD or DL antigens were both reactive with a number of anti-H-2Ld or anti-H-2Dd N/C1-specific monoclonal antibodies, indicating the preservation in the hybrid molecules of determinants controlled by discrete domains. Mab binding was generally greater with cells expressing hybrid DL antigen than with those transformants expressing LD molecules. Moreover, the amount of beta 2M associated with DL antigens was more than that associated with LD. Cells expressing hybrid DL antigens were recognized as targets by bulk and cloned allospecific anti-H-2Dd and anti-H-2Ld CTL, whereas cells expressing LD molecules were not recognized by any of the T cells tested. VSV-specific H-2Ld-restricted CTL failed to lyse VSV-infected targets expressing either DL or LD. These results indicate that T cell reactivity of cells expressing the DL hybrid antigen is an exception to the observed general requirement for class I antigens to possess matched N and C1 domains for functional T cell recognition by T cells restricted to parental antigens.(ABSTRACT TRUNCATED AT 400 WORDS)

Amino Acid Sequence↗
PubMed1986

Behavior problems of equids in zoos.

Behavior problems in zoo equids commonly result from a failure to provide for needs basic to equine nature. Equids are gregarious, and failure to provide companions may result in pacing. Wild equids spend 60 to 70 per cent of their time grazing, and failure to provide ad libitum roughage contributes to the problems of pacing, cribbing, wood chewing, and coprophagia. Mimicking the normal processes of juvenile dispersal, bachelor-herd formation, and mate acquisition reduces the likelihood of agonistic and reproductive behavior problems. Infanticide can be avoided by introducing new stallions to herds containing only nonpregnant mares and older foals.

Aerophagy↗
PubMed1985

Deletion of the proximal long arm of chromosome 3 in an infant with features of Turner syndrome.

A case of deletion of the proximal one-fourth of chromosome 3 long arm is described. While the Turner syndrome phenotype was present neonatally, the patient has no structural or numerical abnormality of the sex chromosomes, and thus may represent an autosomal deletion with a clinical picture similar to Turner syndrome. Her score on the Noonan syndrome index of Duncan et al. (1981) is 27%, making Noonan syndrome unlikely.

Child↗
PubMed1982

Testing counseling psychologists: current practices and implications for training.

The present study provides information concerning the opinions and utilization of psychological testing among counseling psychologists. A survey was mailed to a random sample of 500 members of Division 17 (Counseling Psychology) of the APA. Results indicate that counseling psychologists are engaged in a substantial amount of psychological testing. Current practices are discussed and implications for training are cited. Suggested alternatives to traditional testing procedures are also discussed.

Counseling↗
PubMed1981

Trisomy 14 mosaicism in a translocation 14q15q carrier: probable dissociation and isochromosome formation.

A case of trisomy 14q mosaicism is described and compared with three other similar reported cases. The clinical picture is characterised by severe developmental retardation, failure to thrive, and somatic abnormalities including skeletal asymmetry, high arched or cleft palate, and low set dysplastic ears. The present chromosome imbalance probably resulted from dissociation of a balanced 14q15q translocation with subsequent formation of a 14q isochromosome.

Abnormalities, Multiple↗
PubMed1981

Antimicrobial activity of some alkyl esters of gallic acid (3,4,5,-trihydroxybenzoic acid) against Escherichia coli NCTC 5933 with particular reference to n-propyl gallate.

The growth inhibitory and bactericidal activities of eight alkyl esters of gallic acid towards Escherichia coli NCTC 5933 have been determined. A previously suggested role for gallic acid and its esters as shikimate antimetabolites could not be substantiated. No induction of gross changes in cell morphology was observed. Bactericidal activity was accompanied only be very slight leakage of general ionic materials from the bacteria. Propyl gallate did not appear to uncouple oxidative phosphorylation from respiration as indicated by its failure to stimulate proton translocation across the cytoplasmic membrane.

4-Aminobenzoic Acid↗
PubMed1978

Trisomy 21 with 47,+18 lymphocyte cell line: double mitotic nondisjunction.

A patient with Down's syndrome was found to have 47,XX,+18/47,XX,+21 mosaicism. Chromosome 18 trisomy was found only in 18% of lymphocytes and not in skin fibroblasts. A likely interpretation is double nondisjunction in a single lymphocyte precursor of a trisomy 21 embryo. A brief review of other cases of mitotic multiple nondisjunction and double aneuploid mosiacism is presented.

Adult↗
PubMedDate not supplied

Studies designed to increase the stability and antiviral activity (HCMV) of the active benzimidazole nucleoside, TCRB.

The potent activity of 2,5,6-trichloro-1-(beta-D-ribofuranosyl)benzimidazole (TCRB) against Human Cytomegalovirus with the concomitant low cellular toxicity at concentrations that inhibit viral growth prompted considerable interest in this research area. This interest was moderated by the pharmacokinetic studies of TCRB in rats and monkeys that revealed the instability of TCRB in vivo. These studies suggested that the instability was due to a cleavage of the glycosidic bond in vivo which released the heterocycle (2,5,6-trichlorobenzimidazole) into the bloodstream. This prompted us to initiate synthetic studies designed to increase the stability of the glycosidic bond of TCRB and BDCRB. Several synthetic approaches to address this and other problems are presented.

Animals↗