Osteosarcoma and other bone cancers

Streptokinase (SK), an extracellular protein from Streptococcus equisimilis, is secreted post-translationally by Escherichia coli using both its native and E. coli-derived transport signals. In this communication we report that cleavage specificity of signal peptidase I, and thus efficiency of secretion, varies in E. coli when SK export is directed by different transport signals. The native (+1) N-terminus of mature SK was retained when it was transported under the control of its own, PelB or LamB signal peptide. However, when translocation of SK was controlled by the OmpA or MalE signal peptide, Ala2 of mature SK was preferred as a cleavage site for the pre-SK processing. Our results indicate that compatibility of the leader peptide with the mature sequences of SK, which fulfills the requirement for a given secondary structure within the cleavage region, is essential for maintaining the correct processing of pre-SK. An OmpA-SK fusion, which results in the deletion of two N-terminal amino acid residues of mature SK, was further studied with respect to the recognition of alternative cleavage site in E. coli. The alanine at +2 in mature SK was changed to glycine or its relative position was changed to +3 by introducing a methionine residue at the +1 position. Both alterations resulted in the correct cleavage of pre-SK at the original OmpA fusion site. In contrast, introduction of an additional alanine at +4, creating three probable cleavage sites (Ala-x-Ala-x-Ala-x-Ala), resulted in the recognition of all three target sites for cleavage, with varying efficiency. The results indicate that the nature of the secondary structure generated at the cleavage junction of pre-SK, resulting from the fusion of different signal peptides, modulates the cleavage specificity of signal peptidase I during extracellular processing of SK. Based on these findings it is proposed that flexibility in the interaction of the active site of signal peptidase I with the cleavage sites of signal peptides may occur when it encounters two or more juxtaposed cleavage sites. Preference for one cleavage site over another, then, may depend on fulfillment of secondary structure requirements in the vicinity of the pre-protein cleavage junction.     

Research with the Stanford-Binet, Form L-M: The first five years.

Research literature on the Stanford Binet (S-B), Form L-M, is reviewed beginning with 1960, the year of publication of the latest revision. Major areas include validity, reliability, sensitivity to extratest influences, performance of southern Negro children, influence of socioeconomic status, diagnostic value, and brief forms. Almost all validity studies are concerned with concurrent validity, in which the S-B is correlated with another test. (30 ref.) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Taylor Scale characteristics of volunteers and non-volunteers for psychological experiments.

The hypothesis that there are no differences on the Taylor Manifest Anxiety Scale between volunteers and non-volunteers in a classroom setting was tested by requesting students in introductory classes in psychology and education to volunteer for a psychological experiment, then testing those who volunteered and those who did not. The results give no basis for rejecting the null hypothesis. It would appear that level of anxiety as measured by the MAS is not a factor in the act of volunteering for psychological experiments. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Videotape versus verbal feedback in the modification of meal behavior of chronic mental patients.

Data from "meal behavior indexes" were calculated for 28 chronic adult psychiatric patients who received either videotape or verbal feedback and structured discussions with 2 therapists about their meal behavior. Results show no significant effects attributable to group treatments, therapists, or Therapist * Treatment interactions. The very low level of functioning of these Ss appears to account for results. It is suggested that a token economy offers more promise for this type of patient. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Prediction of an intermediate criterion of combat effectiveness with a biographical inventory.

If, according to biographical data, an individual has tended to engage in risky activities such as contact sports, playing poker, etc., will he also tend to be more effective in combat? Using a Risk Scale and a Peer Rating Scale, 57 seniors enrolled in Army ROTC courses were tested. The criterion was selection of combat and noncombat assignments. For combat effectiveness and leadership, the Risk Scale showed a significant difference in the expected direction. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Further evidence on the ego strength scale as a measure of psychological health.

This study was designed to see if the difference between undergraduates and mental patients obtained by Taft (1957) on the ES Scale represents a difference between college and noncollege populations. Therapy and nontherapy groups in a university setting were compared on the ES scale and results similar to that of Taft were obtained. There was also a trend for self-referred counselees to obtain higher scores on the ES scale than those earned by referred counselees. (PsycINFO Database Record (c) 2010 APA, all rights reserved)