Factors related to depression and eating disorders: self-esteem, body image, and attractiveness.

To test hypotheses that women suffering from some form of eating disorder would experience lower self-esteem and higher depression and that women with lower self-esteem and greater depression would rate their attractiveness lower and see themselves as heavier than less depressed individuals, 42 college undergraduate women were individually administered the Eating Disorders Inventory, Beck Depression Inventory, Coopersmith Self-esteem Inventory, and a Body Image/Attractiveness Perception Scale. A Pearson correlation indicated a substantial relation between scores on depression and scores on eating disorders, but nonsignificant values between self-esteem scores and scores on either eating disorders or on depression. Depression scores correlated significantly with rated body size, but not attractiveness, while self-esteem scores were significantly correlated with rated attractiveness, not body size. These results contradict literature on the relation between self-esteem and depression. Directions for additional research are discussed.

Studies on the entry of viruses into the central nervous system of mice via the circulation. Differential effects of vasoactive amines and CO2 on virus infectivity.

The inhalation of CO(2) exerted a selective action on the entry of viruses into the CNS of mice via the circulation. In 6 wk old animals, the infectivity of poliovirus, vaccinia, and vesicular stomatitis viruses was enhanced, whereas the entry of herpesviruses and of a neurotropic influenza virus was not affected. However, in 3 to 4 wk old mice, inhalation of the gas enhanced the infectivity of all the viruses. To explain the relationship of age to the animals' response to CO(2), it was proposed that CO(2) inhalation, by increasing the rate of cerebral blood flow, served to increase the exposure of some extraneural cell(s) to virus, possibly the cerebrovascular endothelial cell, in which virus replicated and reached the brain parenchyma by direct extension of the infectious process. Consequent to maturation, the postulated target cell developed resistance to certain viruses, while its susceptibility to others remained unchanged. Inoculation of adrenalin or serotonin simultaneously with virus into the circulation enhanced the CNS infectivity of all the viruses tested in both 4 wk and 6 wk age groups of mice. The enhancing effects were completely inhibited by the action of an alpha-adrenergic blocking agent; it was therefore concluded that hemodynamic changes produced by the contractile response of the smooth muscle cells in the vessel walls mediated the enhancing effect. It was suggested that a vasopressor response invoked in the peripheral vessels, with a consequent increase in cerebral blood flow, increased virus dosage to the CNS. In addition, a direct effect of the vasoactive amine on the cerebral vessels, resulting in the disruption of an anatomical "barrier", was considered as a contributory factor in increasing the transfer of virus to the CNS from the circulation.

Further studies of infectious DNA extracted from mycobacteriophages.

Results of the previous investigation in which it was found that DNA extracted from D29 mycobacteriophage was infectious for Mycobacterium smegmatis 607, have been extended. DNA extracted from mycobacteriophage D4 and D32 produced plaques when plated on their respective hosts; D28 DNA, extracted in the same manner and tested under similar conditions, failed to show infectivity. Species barriers were not crossed by mycobacteriophage DNA; bacteria resistant to intact phage were not infected with the phage DNA. The efficiency of plating of the DNA is very much lower than that of intact phage; infection of a given host was not accomplished by DNA when titration for plaque formation by the intact phage was less than 10(9) PFU. The base composition of DNA extracted from the four mycobacteriophages and the three propagating hosts was very similar. The bases were paired, adenine with thymine and guanine with cytosine. A relatively higher per cent of guanine-cytosine than of adenine-thymine, was found. The buoyant density of each DNA in CsCl was linearly related to its guanine-cytosine content whereas with the exception of D28 DNA, thermal denaturation temperatures failed to show this relationship. However, the thermal transition profiles were characteristic of double stranded DNA. Additional evidence that D29 DNA forms complexes with basic proteins was obtained. Binding between calf thymus histone and between RNAase and D29 DNA readily occurs with a resultant loss in DNA infectivity. Trypsin and D29 DNA are only weakly reactive.