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L Bacon

Publications and source records attributed to L Bacon.

26 records · Page 2Linked to original sources

A review of two safety factors in the use of paraldehyde.

Clinical observations and laboratory tests suggest that, contrary to normal practice, paraldehyde can be used with certain plastic syringes and has been safely used when well over six months old. This may make its use as an anticonvulsant in primary care more widely acceptable.

Child↗

Plasma estrogen response to dehydroepiandrosterone sulphate injection in normal and complicated late pregnancy.

Dehydroepiandrosterone sulphate (DHAS) was administered intravenously to 70 women in the third trimester of pregnancy. By measuring the increase in the concentrations of estrogens in maternal plasma, it was hoped to assess the reserve capacity of the placenta. In normal pregnancies, unconjugated estradiol invariably showed a marked increase within 60 minutes of the injection of DHAS, reaching 174 to 478% above basal levels. Changes in unconjugated estrone were more variable, but significant increases usually occurred 2 to 3 hours after the peak concentration of estradiol. The concentrations of unconjugated estriol showed no significant change. Patients with preeclampsia, essential hypertension, retarded intrauterine growth, diabetes, and twin pregnancies did not show any major differences in response compared to the normal pregnancies. Two patients with intrauterine deaths had low basal concentrations of estrogens but responded to the DHAS injection by having significantly increased concentrations of unconjugated estradiol after 60 minutes. The only patient who did not show any increase in unconjugated estradiol levels after DHAS was thought to have a placental sulphatase deficiency. This test does not appear to have any advantage over existing methods of assessing the endocrine function of the placenta except in confirmation of placental sulphatase deficiency.

Dehydroepiandrosterone↗

Characterization of different B-F (MHC class I) molecules in the chicken.

B-F alloantisera recognized distinct 45-Kd molecules on peripheral red blood cells (RBC) from embryonic chickens and heterogeneous molecules of approximately 40 to 44 Kd on peripheral RBC from adult chickens, provisionally referred to as type 1 and type 2, respectively. Type 2 molecules migrated to the basic end of isoelectric focusing gels, exhibited multiple isomorphic variants, and were associated with a smaller polypeptide of approximately 11 to 12 Kd assumed to be beta-2-microglobulin. Type 1 molecules migrated to the acidic end of isoelectric focusing gels, exhibited limited heterogeneity, and were not associated with a smaller polypeptide. Type 1 and type 2 molecules were also shown to be distinct by peptide mapping and serological analyses. In addition, two distinct molecular-weight forms of the type 2 molecules were distinguished, provisionally referred to as 2A (45 Kd) and 2B (42 Kd). In vivo-derived avian erythroblastosis virus (AEV)-transformed erythroleukemia cells expressed type 2A molecules. In vitro-derived AEV-transformed erythroleukemia cells expressed very low levels of B-F molecules; however, they expressed type 2B molecules when induced to differentiate. Normal bursa-derived lymphoid cells expressed type 2A molecules, whereas normal thymus-derived lymphoid cells expressed type 2B molecules. Cloned reticuloendotheliosis virus (REV)-transformed immature lymphoid cells expressed either type 2A or type 2B molecules.

Animals↗

Characterization of two distinct disulfide-linked B-G molecules in the chicken.

Alloantisera specific for B-G antigens recognized a complex of molecules of apparent molecular weights of 90 and 98 Kd under nonreducing conditions and molecules of 40, 44, and 48 Kd under reducing conditions on both embryo- and adult-derived peripheral red blood cells (RBC). The chicken B-G molecules produced a unique two-dimensional "diagonal" pattern. Two antisera permitted the characterization of the complex B-G molecular profile as a homodimer composed of 48-Kd subunits and as a heterodimer composed of 40- and 44-Kd subunits. A rabbit antiserum produced against B-G molecules preferentially recognized the 48-Kd reduced molecules, suggesting that the 90-Kd molecule was a homodimer composed of two 48-Kd molecules. One B-G reagent was capable of recognizing only the 98-Kd nonreduced B-G molecule that gave rise to 40- and 44-Kd molecules under reducing conditions, suggesting that the 98-Kd molecule was a heterodimer composed of 44- and 40-Kd subunits. Adult chicken B-G2 molecules produced a variety of two-dimensional isoelectric focusing/sodium dodecyl sulfate-polyacrylamide gel electrophoresis (IEF/SDS-PAGE) patterns depending on the characteristics of the reagent employed in the immunoprecipitation. B-G molecules were immunoprecipitated from primitive and definitive chicken RBCs but not from any nonerythroid cells tested. B-G molecules were not expressed by avian erythroblastosis virus (AEV)-transformed erythroleukemia cells, nor were they induced to appear with butyric acid-induced erythroid differentiation.

Animals↗