Social,Educational, and Psychological Correlates of Weight Status in Adolescents

Objectives: The purpose of this research was to examine the social, educational, and psychological correlates of weight status in an adolescent population. It was hypothesized that obese adolescents would differ on psychological, social, and educational variables compared with their non‐overweight peers. Research Methods and Procedures: In this cross‐sectional study, a population‐based sample of 4742 male and 5201 female public school students in the 7th, 9th, and 11th grades responded anonymously to a classroom administered questionnaire. Body mass index was calculated from self‐reported height and weight and categorized into four classes of weight status: underweight (<15th percentile), average weight (15th to 85th percentile), overweight (>85th to 95th percentile), and obese (>95th percentile). The questionnaire also included questions about social experiences, psychological well‐being, educational experiences, and future goals. Associations of weight status with social, psychological, and educational variables and future goals were explored. Results: After adjustment for grade level, race, and parental socioeconomic status, obese girls, when compared with their average weight counterparts, were 1.63 (95% confidence interval [CI]: 1.16, 2.30) times less likely to hang out with friends in the last week, 1.49 (95% CI: 1.12, 1.98) times more likely to report serious emotional problems in the last year, 1.79 (95% CI: 1.20, 2.65) times more likely to report hopelessness, and 1.73 (95% CI: 1.21, 1.98) times more likely to report a suicide attempt in the last year. Obese girls were also 1.51 (95% CI: 1.09, 2.10) times more likely to report being held back a grade and 2.09 (95% CI: 1.35, 3.24) times more likely to consider themselves poor students compared with average weight girls. Compared with their average weight counterparts, obese boys were 1.91 (95% CI: 1.43, 2.54) times less likely to hang out with friends in the last week, 1.34 (95% CI: 1.06, 1.70) times more likely to feel that their friends do not care about them, 1.38 (95% CI: 1.08, 1.76) times more likely to report having serious problems in the last year, 1.46 (95% CI: 1.05, 0.03) times more likely to consider themselves poor students, and 2.18 (95% CI: 1.45, 3.30) times more likely to expect to quit school. Compared with average weight boys, underweight boys were 1.67 (95% CI: 1.30, 2.13) times more likely to report hanging out with friends in the last week, 1.22 (95% CI: 1.01, 1.49) times more likely to report disliking school, and 1.40 (95% CI: 1.06, 1.86) times more likely to consider themselves poor students. Discussion: Associations of weight status with social relationships, school experiences, psychological well‐being, and some future aspirations were observed. Among girls, the pattern of observations indicates that obese girls reported more adverse social, educational, and psychological correlates. Obese as well as underweight boys also reported some adverse social and educational correlates. These findings contribute to an understanding of how adolescent experiences vary by weight status and suggest social and psychological risks associated with not meeting weight and body shape ideals embedded in the larger culture.     

Loss of heterozygosity on chromosome 10 in human glioblastoma multiforme

Recessive mutations, revealed by loss of the wild-type allele, have been associated with the development of a variety of cancers in children and adults. Polymorphic chromosome 10 markers were used to screen paired tumor and lymphocyte DNA samples in 13 patients with glioblastoma multiforme. Ten patients showed loss of constitutional heterozygosity in the tumor samples. This finding suggests that a recessive gene involved in the development of glioblastoma multiforme is present on chromosome 10.     

Characterization of an aminoacylase from the hyperthermophilic archaeon Pyrococcus furiosus.

Aminoacylase was identified in cell extracts of the hyperthermophilic archaeon Pyrococcus furiosus by its ability to hydrolyze N-acetyl-L-methionine and was purified by multistep chromatography. The enzyme is a homotetramer (42.06 kDa per subunit) and, as purified, contains 1.0 +/- 0.48 g-atoms of zinc per subunit. Treatment of the purified enzyme with EDTA resulted in complete loss of activity. This was restored to 86% of the original value (200 U/mg) by treatment with ZnCl(2) (and to 74% by the addition of CoCl(2)). After reconstitution with ZnCl(2), the enzyme contained 2.85 +/- 0.48 g-atoms of zinc per subunit. Aminoacylase showed broad substrate specificity and hydrolyzed nonpolar N-acylated L amino acids (Met, Ala, Val, and Leu), as well as N-formyl-L-methionine. The high K(m) values for these compounds indicate that the enzyme plays a role in the metabolism of protein growth substrates rather than in the degradation of cellular proteins. Maximal aminoacylase activity with N-acetyl-L-methionine as the substrate occurred at pH 6.5 and a temperature of 100 degrees C. The N-terminal amino acid sequence of the purified aminoacylase was used to identify, in the P. furiosus genome database, a gene that encodes 383 amino acids. The gene was cloned and expressed in Escherichia coli by using two approaches. One involved the T7 lac promoter system, in which the recombinant protein was expressed as inclusion bodies. The second approach used the Trx fusion system, and this produced soluble but inactive recombinant protein. Renaturation and reconstitution experiments with Zn(2+) ions failed to produce catalytically active protein. A survey of databases showed that, in general, organisms that contain a homolog of the P. furiosus aminoacylase (> or = 50% sequence identity) utilize peptide growth substrates, whereas those that do not contain the enzyme are not known to be proteolytic, suggesting a role for the enzyme in primary catabolism.     

Cryostat Techniques: Methods for Improving Conservation and Sectioning of Tissue

Tissues have been conserved for satisfactory enzymatic histochemical assay for up to 12 mo by low temperature storage (in a dry ice chest or at -40° C) and by measures designed to offset the deleterious effects of sublimation of H₂O by using the following modifications of standard procedures (which include steps to give a mechanical support to otherwise fragmenting sections): 1. tissue blocks are coated with a polystyrene solution between each storage period; 2. modified bolts are used as tissue holders and types of bolt holders have been designed to fit on standard microtomes which permit manipulation of each tissue block independently of its mates on the same bolt holder, or the simultaneous cutting of all blocks on any one holder with each advance of the microtome feed; 3. tissues are coated with 20% polystyrene in methylene chloride prior to cutting and rubber cement painted on the slide as an adhesive. Lillie's 20% polystyrene diethylbenzene is used as a mounting medium. Other details of practical importance include the technique of freezing, control of moisture within a cryostat and on the microtome, and tests on histochemical procedures.     

Lamin B is a prompt heat shock protein

The cellular response to hyperthermia involves the increased synthesis of heat shock proteins (HSPs) within several hours after treatment. In addition, a subset of proteins has been shown to be increased immediately after heating. These “prompt” HSPs are predominantly found in the nuclear matrix–intermediate filament fraction and are not present or detectable in unheated cells. Since the nuclear matrix has been suggested to be a target for heat-induced cell killing, prompt HSPs may play a prominent role in the heat shock response. Using Western blotting and flow cytometry, we found that an increase in the synthesis of lamin B, one of the major proteins of the nuclear lamina, is induced during heating at 45.5°C but not during heating at 42°C. Since it is an abundant protein which is constitutively expressed in mammalian cells, lamin B appears to be a unique member of the prompt HSP family. The kinetics of induction of lamin B during 45.5°C heating did not correlate with the dose-dependent reduction in cell survival. While increased levels of lamin B during 45.5°C heating do not appear to confer a survival advantage directly, a possible role for lamin B in cellular recovery after heat shock cannot be discounted. J Cell Physiol 178:28–34, 1999. © 1999 Wiley-Liss, Inc.