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Biomedical subjects

K Pierce

Publications and source records attributed to K Pierce.

7 recordsLinked to original sources
PubMed1991

Efficacy of acemannan in treatment of canine and feline spontaneous neoplasms.

Forty-three dogs and cats with spontaneous tumors were treated with the immunostimulating polysaccharide acemannan by intraperitoneal and intralesional routes of administration. Tumors from 26 of these animals showed histopathological evidence of immunological attack as shown by marked necrosis or lymphocytic infiltration. Thirteen showed moderate to marked tumor necrosis or liquefaction. Twenty-one demonstrated lymphoid infiltration, and seven demonstrated encapsulation. Twelve animals showed obvious clinical improvement as assessed by tumor shrinkage, tumor necrosis, or prolonged survival; these included five of seven animals with fibrosarcomas. It is believed that acemannan exerts its antitumor activity through macrophage activation and the release of tumor necrosis factor, interleukin-1, and interferon.

Adjuvants, Immunologic↗
PubMed1990

Expression of functional coagulation factor XIII in Escherichia coli.

Coagulation factor XIII is a zymogen that can be activated by thrombin cleavage to a transglutaminase that catalyses the formation of covalent crosslinks between fibrin chains in the final stages of the blood clotting cascade. Although circulating factor-XIII is composed of A and B subunits the catalytic activity is a property of the A subunits. In this study we have constructed a plasmid (pKKF13A) that contains a cDNA encoding the A subunit positioned downstream of a tac promoter. Escherichia coli containing this plasmid produce A subunit protein when grown in the presence of IPTG. The cloned A subunit has been partially purified and characterized. Comparison with A subunits purified from plasma showed that the cloned A subunits were of the same size, assembled as dimers, and had the same native electrophoretic mobility. The cloned A subunits expressed transglutaminase activity with putrescine, dansylcadaverine and casein as substrates, and were able to crosslink fibrin in clots formed from A subunit deficient plasma. These studies have demonstrated that functional recombinant factor XIII A subunit can be produced in E. coli and suggest that recombinant factor XIII can potentially provide a safe and inexhaustible supply for therapeutic use.

Amino Acid Sequence↗
PubMed1989

The conjugative plasmid pTR2030 encodes two bacteriophage defense mechanisms in lactococci, restriction modification (R+/M+) and abortive infection (Hsp+).

pTR2030 is a conjugative plasmid which encodes resistance to bacteriophage in lactococci by a mechanism that aborts the phage infection (Hsp+). Subcloning and in vivo deletion events showed that two independent mechanisms of resistance are located on a 13.6-kilobase Bg/II fragment cloned in pSA3; one mechanism is responsible for the abortive infection, and the other incodes a restriction modification system. The introduction of pTR2030 or the recombinant plasmid pTK6 resulted in the loss of a resident restriction modification plasmid in Lactococcus lactis NCK202 which was not previously identified.

Bacteriophages↗