Prolonged inhibition of muscle carnitine palmitoyltransferase-1 promotes intramyocellular lipid accumulation and insulin resistance in rats.

Cross-sectional studies in human subjects have used 1H magnetic resonance spectroscopy (HMRS) to demonstrate that insulin resistance correlates more tightly with the intramyocellular lipid (IMCL) concentration than with any other identified risk factor. To further explore the interaction between these two elements in the rat, we used two strategies to promote the storage of lipids in skeletal muscle and then evaluated subsequent changes in insulin-mediated glucose disposal. Normal rats received either a low-fat or a high-fat diet (20% lard oil) for 4 weeks. Two additional groups (lowfat + etoxomir and lard + etoxomir) consumed diets containing 0.01% of the carnitine palmitoyltransferase-1 inhibitor, R-etomoxir, which produced chronic blockade of enzyme activity in liver and skeletal muscle. Both the high-fat diet and drug treatment significantly impaired insulin sensitivity, as measured with the hyperinsulinemic-euglycemic clamp. Insulin-mediated glucose disposal (IMGD) fell from 12.57 +/- 0.72 in the low-fat group to 9.79 +/- 0.59, 8.96 +/- 0.38, and 7.32 +/- 0.28 micromol x min(-1) x 100 g(-1) in the low-fat + etoxomir, lard, and lard + etoxomir groups, respectively. We used HMRS, which distinguishes between fat within the myocytes and fat associated with contaminating adipocytes located in the muscle bed, to assess the IMCL content of isolated soleus muscle. A tight inverse relationship was found between IMGD and IMCL, the correlation (R = 0.96) being much stronger than that seen between IMGD and either fat mass or weight. In conclusion, either a diet rich in saturated fat or prolonged inhibition of fatty acid oxidation impairs IMGD in rats via a mechanism related to the accumulation of IMCL.

The place of self-esteem in interpersonal behavior.

Two measures of self-esteem (Confidence and Perceived Social Approval) were administered with the short form of the Interpersonal Style Inventory to 75 male high school students. The purpose was to determine the place of self-esteem in the domain of interpersonal behavior. A principal components analysis of the intercorrelations among the 17 scale scores disclosed six factors. After an oblique rotation (Promax) the factors were interpreted as higher-order dimensions of Impulse Control, Level of Socialization, Interpersonal Involvement, and Autonomy. Confidence and Popularity emerged as two separate factors; the first was seen as a broad dimension of self-confident, rule-free stability.

Factors common to the ISI and the 16PF inventories.

This study tested for five higher-order dimensions hypothesized to be common to the Interpersonal Style (ISI) and the 16PF questionnaires. A sample of detoxified alcohol dependent inpatients (N = 50) were administered the ISI and the 16PF on two separate occasions. The 31 scale intercorrelations were analyzed by the method of principal axes. An oblique factor structure obtained by use of the Promax procedure confirmed the factors expected. These were interpreted as representing Self Control, Interpersonal Involvement or Exvia, Emotional Stability or reversed 16PF Anxiety, Independence, and Level of Socialization. At least two or three closely similar higher-order factors have been isolated on each of three other popular inventories (PRF, CPI and GZTS). The existence of such common dimensions should facilitate the interpretation and confirmation of distinctive score profiles.

The Coopersmith Self-Esteem Inventory: analysis and partial validation of a modified adult form.

Determined the factor structure of an adult form of the Coopersmith Self-Esteem Inventory (SEI), tested several hypotheses related to its content, and assessed the utility of the five derived scores for differentiating psychiatric outpatients from normals. The modified Self-Esteem Inventory and six other scales were completed by 200 local-government employees. A principal components analysis of correlations among 58 SEI items and two marker variables revealed five factors. The rotated dimensions were labelled (1) anxiety; (2) defensiveness; (3) negative social attitude; (4) rejection of self; and (5) inadequacy of self. Fifty psychiatric outpatients were compared with 100 normals with respect to the five derived factor scores. Tests of significance indicated that the two groups differed significantly on all measures except the defensiveness or lie scale factor. It is concluded that the Coopersmith Inventory is complex and measures several characteristics in addition to self-esteem.