Interrelationships among subgroups of serum lipoproteins in normal human subjects

Analytic ultracentrifugation of serum lipoproteins from 80 men and 54 women aged 27--66 was used to determine if specific segments of the high density (HDL), low density (LDL) and very low density (VLDL) lipoprotein schlieren curves could be defined so as to reveal significant correlations among them. Differences in correlations resulted in division of LDL into three subgroups based on flotation rate S(0)(f) 0--7, 7--12, and 12--20) and division of HDL into two subgroups F(0)(1.20) 0--1.5 and s--9). HDL of F(0)(1.20) 2--9 (designated HDL 2--9) correlated negatively with LDL of S(0)(f) 0--7 (LDL 0--7) for all groups, positively with LDL of S(0)(f) 7--12 except in women aged 27--46, and negatively with VLDL except in men aged 47--66. HDL of F1.20(0) 0--1.5 (HDL0-1.5) correlated positively with LDL 0-7 except in men aged 27--46 and with VLDL in all but older men. Some correlations were reduced to non-significant levels by controlling for LDL (0-7) or VLDL. Correlations of HDL and LDL flotation subgroups yielded no significant net correlation between total HDL and LDL. Total HDL was directly correlated with HDL (2-9) (r greater than 0.97) but not with HDL0-1.5. The foregoing suggests that decreased HDL represents reduced HDL2-9 and may be accompanied by increased LDL0-7 and VLDL. LDL0-7 may represent and "atherogenic" LDL subclass in part responsible for increased coronary risk associated with low HDL.

Fecal bile acids in two Japanese populations with different colon cancer risks

Some workers have associated fecal bile acids with colon cancer frequency. They suggest that the risk for colon cancer increases with a rise in the level of total and degraded fecal bile acids. The Japanese in Hawaii, who are at high risk for this cancer, had higher concentrations of deoxycholic acid (a degraded bile acid) in their fecal specimens than did the people in Akita, Japan, who are at low risk. However, the findings for the other bile acids were unremarkable or inconsistent. These data were suggestive, but not strongly supportive, of a relationship between fecal bile acid patterns and colon cancer risk.

Linear discriminant function analysis in neuropsychological research: some uses and abuses

The present paper addressed the continued misinterpretation and misapplication of linear discriminant function analysis in neuropsychological research. Methodological problems concerning the influence of shrinkage and stepwise selection procedures on LDFA are virtually ignored and affect both the classification and inferential application of LDFA. Throughout the paper examples of potential abuses of LDFA were cited and data from a familiar research problem was employed to demonstrate procedures which enable more accurate interpretation of LDFA results. Linear discriminant function analysis and its multivariate equivalents are powerful and flexible tools for exploring group differences provided appropriate applications and interpretations of results are made.

Analysis of fecal bile acids and diet among the Japanese in Hawaii

Fecal samples of 165 Japanese men in Hawaii, age 43 to 74, were analyzed for bile acid content by their conversion to the methyl ester and the trimethylsilyl ether derivative followed by separation on a gas chromatograph. The arithmetic mean of total bile acids for the 165 specimens was 10.96 mg/g dry weight feces. Each of the following bile acids was detectable in over 77% of the fecal specimens: cholic, deoxycholic, lithocholic, and cholanic acid. The intake of Western foods was not positively correlated with the fecal content of secondary or modified bile acids, even though other workers have observed that these bile acids predominated in persons from Westernized countries. Two of the Japanese foods were negatively correlated with the levels of modified bile acids, which suggested that these foods contributed to a decrease in modified bile acids in fecal specimens. Fecal bile acid measurements appeared to be associated with age, but not with weight, height, or serum cholesterol levels.

Cardiac structure growth pattern determined by echocardiography

Using M-mode echocardiography, we measured dimensions of the ventricular walls and cavities, great vessels, and left atrium and atrioventricular valve excursions on 93 infants and children without heart disease. The data were analyzed by relating each dimension in mm to body surface area in m2 and the 90% tolerance limits for the data were calculated. The tolerance lines of the data were wider than previously recorded. At birth and maturity they were similar to the range defined as normal by studies in neonates and adults. We suggest that the tolerance lines of these normal data may be used for quantitative echocardiography in childhood.

Comparisons between direct microscopic and cultural methods for recognition of Corynebacterium vaginale in women with vaginitis

The frequency with which clue cells could be detected in Gram-stained vaginal smears and/or cervical Papanicolaou (Pap) smears was compared with the frequency of Corynebacterium vaginale (Haemophilus vaginalis) isolation in a group of 236 female patients, of whom 221 had vaginitis. Vaginal clue cells were found most often in women from whom C. vaginale was isolated (P = 0.00006) whereas, conversely, clue cells in cervical Pap smears were reported more frequently in women with negative cultures for this organism (P = 0.006). C. vaginale isolations were made more frequently from women with both vaginal and cervical clue cells reported (P = 0.000088). However, the combined false positive-false negative vaginal clue cell rate in the patients studied was 36.5%. Neither the detection of vaginal clue cells nor the isolation of C. vaginale was significantly affected by whether or not patients had trichomoniasis (P = 0.25). Trichomonas vaginalis detection in cervical Pap smears and vaginal isolation were related (P = 0.00005), whereas the same relationship was not significant for fungi (P = greater than 0.05).