Abnormal enzyme phenotype (E1a E1f): normal response to succinylcholine.

The enzyme serum cholinesterase responsible for the hydrolysis of the muscle relaxant succinylcholine exists in the form of several variants. These may be identified in serum by using substances which inhibit their activity to different degrees. The heterozygote for the atypical and fluoride resistant enzymes (E1a E1f) is one of the phenotypes which has been reported to be sinsitive to succinylcholine.

Lipoidal bladder concretion: an unusual autopsy finding in acute lymphoblastic leukemia.

The occurrence of a large (2.3 gm.), wax-like, creamy white concretion in the bladder of a 7-year-old girl who died of acute lymphoblastic leukemia is reported.

Evaluation of an automated immunoassay procedure for apo-LDL for phenotyping type II hyperlipoproteinemia.

Apo-low density lipoproteins were determined by an automated immunoassay procedure on serum samples from 88 normolipidemic individuals and 84 hyperlipoproteinemic subjects, to establish whether this method was useful in the routine detection of type II hyperlipoproteinemia. The results obtained were compared with the cholesterol levels of the same specimens. In subjects with type II hyperlipoproteinemia, the apo low density lipoprotein levels, as well as the ratio of low density lipoprotein cholesterol/apo-low density lipoprotein were higher, as expected, than in normals or in subjects with other types of hyperlipoproteinemia.

Use of a programmable calculator in processing and interpreting serum cholinesterase phenotypes.

Cholinesterase phenotyping is done at 25 degrees C with use of benzoylcholine as substrate and dibucaine, fluoride, chloride, and succinyldicholine as inhibitors. We wrote a diagnostic program in modified BASIC language for the processing and interpretation of these cholinesterase phenotypes. We used the HP 9830A calculator.

Succinylcholine sensitivity in a Nova Scotia family.

Succinylcholine apnoea is usually the result of a delay in hydrolysis of the injected muscle relaxant due to the presence of an inherited defect in the enzyme cholinesterase. This report presents a Nova Scotia family in whom several members had "difficulty in breathing" following anaesthesia. Subsequent investigations revealed the presence of several phenotypes of the enzyme cholinesterase including individuals who were homozygous for the atypical cholinesterase genes.

True Arrhenius relationships of human lactate dehydrogenase.

The pyruvate and NADH concentrations and the buffer pH which gave maximal activity with LDH isoenzymes derived from human heart and liver tissue were established for the temperatures 25 degrees C, 30 degrees C, 35 degrees C, 37 degrees C,, 40 degrees C, 45 degrees C, and 50 degrees C. The velocities of the LDH isoenzymes using these maximal assay conditions were used to obtain Arrhenius plots, i.e.