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This study examined bidirectional relationships between age at first sexual intercourse and academic goals and achievement. It was hypothesized that lower educational goals and achievement would be associated with initiating sexual intercourse at a younger age, and that initiating sexual activity early would be associated with a decrease in subsequent academic achievement and goals. In longitudinal data spanning 11 years, evidence was found for bidirectional effects. One interpretation of these results is that adolescents with high educational goals and achievement delay having intercourse because of the perceived risks (e.g., pregnancy and sexually transmitted diseases may jeopardize their plans for the future). Conversely, adolescents who engage in sexual intercourse at young ages might undergo a change in attitudes, including reduced interest in academic achievement and goals. The specific educational variables most strongly related to adolescent sexual intercourse in this study differed substantially by race and gender.

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UNLABELLED: A larger proportion of adopted adolescents receive mental health counseling than do their nonadopted peers. Adoptees might have more problems that require counseling, or their adoptive parents might have a lower threshold for referral (or both). OBJECTIVE: To test the hypothesis that both the extent of adolescents' problems and their adoption status would predict whether adolescents received psychological counseling, after controlling for family demographic characteristics. METHOD: Two large data sets collected from 1994 through 1996 by the National Longitudinal Study of Adolescent Health (Add Health) were used. In parallel analyses of the 2 data sets, hierarchical logistic regression models were implemented to assess the incremental effects of problem behaviors, family characteristics, and adoption status on adolescents receiving counseling. RESULTS: Selected adolescents' problems and family demographic characteristics were significant predictors for having received counseling, but, after controlling for these variables, adoptees were still about twice as likely as nonadoptees to have received counseling. CONCLUSIONS: Prevalence of problems, adoptive family characteristics, and adoption status must all be taken into account to understand why adoptees are more likely to receive counseling. Clinicians should be sensitive to issues that are especially salient in adoptive families.

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There are conflicting findings about whether adopted children have more psychological and behavioral problems than nonadoptees. Research results are discrepant partly because many previous studies were based on small clinical samples or on samples biased by self-selection. A nationally representative school survey (Add Health) was used to compare adopted (n = 1,587) and nonadopted adolescents (total N = 87,165) across a wide variety of measures. Standardized mean differences show that adopted adolescents are at higher risk in all of the domains examined, including school achievement and problems, substance use, psychological well-being, physical health, fighting, and lying to parents. Demographic and background variable breakdowns show that the effect sizes for differences between adopted and nonadopted adolescents were larger for males, younger or older adolescents, Hispanics or Asians, and adolescents living in group homes or with parents of low education. Distributional analyses revealed approximately a 1:1 ratio of adopted to nonadopted adolescents in the middle ranges of the outcome variables but a ratio of 3:1 or greater near the tails of the distributions. These data clearly show that more adopted adolescents have problems of various kinds than their nonadopted peers; effect sizes were small to moderate based on mean differences, but comparisons of distributions suggest much larger proportions of adopted than nonadopted adolescents at the extremes of salient outcome variables.

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OBJECTIVE: The aim of this research was to investigate if there is a higher incidence of child abuse following major natural disasters. METHODOLOGY: Child abuse reports and substantiations were analyzed, by county, for 1 year before and after Hurricane Hugo, the Loma Prieta Earthquake. and Hurricane Andrew. Counties were included if damage was widespread, the county was part of a presidential disaster declaration, and if there was a stable data collection system in place. RESULTS: Based on analyses of numbers, rates, and proportions, child abuse reports were disproportionately higher in the quarter and half year following two of the three disaster events (Hurricane Hugo and Loma Prieta Earthquake). CONCLUSIONS: Most, but not all, of the evidence presented indicates that child abuse escalates after major disasters. Conceptual and methodological issues need to be resolved to more conclusively answer the question about whether or not child abuse increases in the wake of natural disasters. Replications of this research are needed based on more recent disaster events.

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The EL-4 thymoma cell line contains a peptidase which converts beta-endorphin to beta-endorphin 1-17 (gamma-endorphin), beta-endorphin 1-18, and their corresponding C-terminal fragments. This enzyme was purified approximately 700-fold to a single band on an SDS-polyacrylamide gel (106 kDa) in 16% yield. Estimation of the native molecular weight by molecular sieve chromatography gave a value of approximately 220 kDa, indicating that this enzyme is a dimer. Peptide sequencing demonstrated this activity can be attributed to insulin degrading enzyme, a previously described member of the inverzincin family (Hooper, 1994). Kinetic studies with a number of peptide substrates indicate that the enzyme preferentially cleaves on the amino side of hydrophobic or basic residues. However, the substrate specificity is more complex since not all basic and hydrophobic residues in a peptide are cleaved. The enzyme exhibits a requirement for a P'2 residue. On the basis of kcat/K(m) values, insulin, growth hormone releasing factor, and beta-endorphin are nearly equivalent substrates for the enzyme; however, growth hormone releasing factor and beta-endorphin exhibit a 40-fold higher kcat, but a 10-fold decreased affinity relative to insulin. A role for insulin-degrading enzyme as both a beta-endorphin-processing and -inactivating enzyme is implicated from these studies.

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Beta-endorphin metabolism by CD4+ and CD8+ T cells, and the thymoma cell line, EL4, was investigated. In all three cell types, extracellular beta-endorphin was metabolized exclusively by a secreted, metal-dependent, thiol peptidase. The enzyme activity is expressed constitutively in EL4 cells and following activation of CD4+ and CD8+ T cells with anti-CD3 antibody. The enzyme is not one of the proteinases associated with cytolytic T cells and does not appear to be identical with any previously described beta-endorphin metabolizing enzyme. The enzyme cleaves beta-endorphin at approximately equal rates at either of two sites to yield beta-endorphin(1-17) (which is gamma-endorphin), beta-endorphin(1-18), beta-endorphin(18-31) and beta-endorphin(19-31). Evidence in the literature indicates that these N- and C-terminal peptides which contain, respectively, the opioid and non-opioid receptor binding domains of beta-endorphin, are biologically active. Thus, it is likely that this new T cell peptidase has important immunoregulatory activity.

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In the 1987 National Survey of Children the question was asked: "Was there ever a time when you were forced to have sex against your will, or were you raped?" Among White females, aged 18-22, those who answered yes (n = 41) and no (n = 400) were compared on a number of social-psychological and sexual variables that might be thought of as outcomes affected by having had coercive sexual experience(s). Those who reported being forced to have sexual intercourse, compared to those who did not, had more permissive attitudes about 16-17-year-olds having intercourse and a younger age of first voluntary sexual intercourse themselves. They also had lower internal locus of control and higher depression scores, and they needed and received more psychological help than those not reporting forced sexual intercourse. Dividing the forced sexual intercourse group (FSI) into those reporting FSI before versus after their first date, and those whose FSI was before versus after age 12, yielded essentially the same findings. Even in the presence of multivariate control variables. FSI experience remained a significant predictor of age at first voluntary sexual intercourse, locus of control, depression, and perceived need for psychological help. These analyses of national survey data support the clinical perspective that forced sexual intercourse causes or exacerbates various sexual and psychological problems.

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This study was performed to determine the magnitude and time of onset of in vivo changes in hepatic bioenergetics in response to a sublethal dose of lipopolysaccharide (LPS), a bacterial endotoxin. Male rats (48-hour-fasted) were administered an intraperitoneal injection of LPS (5 mg/kg body weight) or vehicle alone, and the livers were freeze-clamped 5, 30, or 180 minutes or 24 hours later. Liver tissue was extracted with perchloric acid, and the metabolites necessary to calculate NAD(+)- and NADP(+)-linked redox states and the cytosolic phosphorylation potential were measured. There was no significant difference in hepatic cytosolic phosphorylation potential between LPS and control groups at any of the times investigated. This indicated that the ability of the liver to synthesize adenosine triphosphate (ATP) was not compromised under the conditions of the study. No changes in hepatic redox states were observed 5 or 30 minutes after LPS treatment. Three hours after LPS treatment, hepatic cytosolic and mitochondrial free-[NAD+]/[NADH] redox states and the cytosolic free-[NADP+]/[NADPH] redox state were more oxidized. By 24 hours, only NAD(+)-linked redox states were more oxidized than the time-matched controls. Hepatic urea content was elevated at both 3 and 24 hours, compatible with an increased rate of urea synthesis as a consequence of increased amino acid metabolism, whereas hepatic beta-hydroxybutyrate and total ketone bodies were decreased 24 hours after LPS treatment, indicating decreased hepatic ketogenesis.(ABSTRACT TRUNCATED AT 250 WORDS)

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Day treatment, or partial hospitalization, may have unique advantages for the treatment of patients with borderline personality disorder. Such treatment may offer patients the optimal level of intensiveness and containment, resulting in less regressive dependency and acting-out behavior. To be successful in treatment of patients with borderline personality disorder, a day treatment program should facilitate the patient's need to experience and express affect safely, optimize the program's ability to provide less restrictiveness than inpatient treatment but more sustained and intensive support than outpatient treatment, and use verbal and nonverbal approaches to help patients maintain primary responsibility for their well-being. A length of stay of three weeks allows patients to regain baseline functioning and resume long-term outpatient care. Treatment goals should be clear and resolvable in three weeks.

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Exogenous methionine enkephalin incubated with CD4+ or CD8+ T cells purified from murine spleen is metabolized primarily, if not exclusively, by aminopeptidase N (aminopeptidase M, EC 3.4.11.2), a membrane-anchored ectopeptidase. The enzyme activity is identified by its substrate specificity, sensitivity to inhibition by amastatin, and immunoreactivity with antibody to rat kidney aminopeptidase N. Activation of CD4+ T cells results in a small increase per cell in aminopeptidase N activity.

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13C NMR analysis of 13C-enriched glucose containing multiple isotopomers is hampered by chemical shift similarities of several carbon resonances and by the presence of two anomeric forms. A convenient and quantitative method of enzymatically oxidizing glucose to gluconate in tissue and perfusate extracts is presented. The six carbon resonances of the resulting 13C-enriched gluconate are fully resolved at high pH, thereby allowing a determination of the fractional population of each 13C isotopomer by 13C NMR. The utility of this method is demonstrated using the effluent from an isolated perfused liver containing 13C-enriched glucose produced by hepatic metabolism of sodium [1,2,3-13C3]propionate via the citric acid cycle and gluconeogenesis. An analysis of the gluconate C2 and C5 resonances in this sample showed that pentose phosphate activity was insignificant during this perfusion protocol. As demonstrated, this method provides a means of fully describing 13C isotopomer populations in enriched glucose samples where isotope may be derived from multiple metabolic pathways, thus expanding the scope of experimental design and enrichment strategies.

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Ectopeptidases which hydrolyze opioid and other neuropeptides have been identified in brain, kidney and intestine. In this study, identification of the enzymes metabolizing the opioid peptide methionine enkephalin (YGGFM) in murine macrophages was undertaken. Incubation of methionine enkephalin with intact murine peritoneal macrophages results in five products identified as Y, F, FM, GFM and GGFM by amino acid analysis and peptide microsequencing after fractionation by HPLC. The spectrum of metabolites results from at least two distinct aminopeptidase activities. The enzyme hydrolyzing YGGFM to GGFM is identified as the membrane-anchored aminopeptidase N (ApN; EC 3.4.11.2) based on its substrate specificity and inhibitor profile. A distinct bestatin and amastatin sensitive aminopeptidase catalyzes hydrolysis of GGFM to GFM. The macrophage ApN protein has a larger mass and is antigenically distinct from murine kidney ApN, which is suggested to result from glycosylation differences rather than expression of a distinct protein. The ApN catalytic activity and mRNA levels are increased in thioglycollate-elicited as compared to resident peritoneal macrophages. RT-PCR analysis identified a 0.7 kb fragment of the ApN coding sequence which was identical in mouse kidney and thioglycollate-elicited peritoneal macrophages and which has 89% identity with the corresponding rat kidney ApN cDNA sequence.

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The rate of carbohydrate flux through phosphofructokinase (measured as the rate of [3-3H]glucose detritiation) was increased fourfold in rat liver parenchymal cells incubated with conditioned medium from lipopolysaccharide-stimulated adherent liver non-parenchymal cells. The rate was not affected in parenchymal cells incubated either with lipopolysaccharide directly or with conditioned medium from non-stimulated non-parenchymal cells. The stimulation of carbohydrate flux through phosphofructokinase by conditioned medium was not duplicated by peptide cytokines known to be released by lipopolysaccharide-activated liver non-parenchymal cells (interleukin-1, interleukin-6, tumor necrosis factor-alpha, and transforming growth factor-beta) or platelet activating factor. Furthermore, formation of the active conditioned medium was not prevented by inclusion of cycloheximide or dexamethasone to inhibit cytokine synthesis, or indomethacin or BW755c to inhibit arachidonic acid metabolism, during lipopolysaccharide-stimulation of the non-parenchymal cells. The results indicate that intercellular communication between lipopolysaccharide-stimulated liver non-parenchymal cells and parenchymal cells by soluble mediators is responsible for the stimulation of liver phosphofructokinase activity during endotoxin-induced shock. Studies to isolate and identify the factor(s) in the conditioned medium are currently in progress.

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PIP: Economic disadvantage and limited opportunities have been viewed as fundamental causes of adolescent pregnancy and childbearing. Adolescents who become pregnant and bear children, however, often suffer adverse social and economic consequences. Much of the economic burden of raising these children falls upon extended family members and the public sector. Socioeconomic disadvantage is thus a cause and a consequence of adolescent pregnancy and childbearing, with women who become mothers as teenagers at greater risk of social and economic disadvantage throughout their lives than those who delay childbearing until their twenties. They are less likely to complete their education, to be employed, to earn high wages, and to be happily married. These women are also more likely to have larger families and to receive welfare. The author reviews and summarizes recent research and revisionist debates on these issues, and considers the implications for social policy. Emphasis is given to prevention approaches which build upon postponing adolescent sexual intercourse and helping sexually active teens avoid pregnancy.^ieng

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PIP: Sexual intercourse and contraceptive use are fertility-related behaviors. Such behavior affects the risks of adolescent pregnancy, abortion, birth, adoption, and parenthood. The issue of adolescent sexuality gained prominence during the 1980s. This paper introduces and briefly reviews a group of five empirical studies which focus upon the fertility-related behavior of adolescents in the 1990s. Synopses of each study are provided. The authors find that these articles shed considerable light upon the many issues involved in adolescent sexual behavior. They are based upon some of the richest and most recent data sets available. As the 1990s begin, there is no indication that adolescents will decrease their level of sexual activity, and it is too soon to tell whether the apparent recent increase in condom use will result in lower pregnancy rates.^ieng

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Release of eicosanoids is an important response of macrophages to inflammation and bacterial infection. At low concentrations, bacterial lipopolysaccharide (1-2 micrograms/ml) fails to stimulate eicosanoid release in resident peritoneal macrophages but primes the macrophages for a greatly enhanced release of eicosanoids on stimulation with the calcium ionophore A23187 (0.1 microM) or with phorbol 12-myristate 13-acetate (50 nM), an activator of protein kinase C. Incubation of macrophages with Bordetella pertussis toxin, prior to priming with lipopolysaccharide, inhibited the release of both cyclooxygenase and lipoxygenase products upon A23187 stimulation. Pertussis toxin treatment of macrophages had no effect on eicosanoid release when the stimulus was phorbol 12-myristate 13-acetate. The presence of 1-(5-isoquinolinylsulfonyl)-2-methylpiperazine (H-7), an effective inhibitor of protein kinase C, during lipopolysaccharide priming and subsequent stimulation significantly inhibited eicosanoid release when phorbol 12-myristate 13-acetate was the stimulus, but did not affect eicosanoid release stimulated by A23187. Based on these results, at least two mechanisms, distinguished by apparent differences in sensitivity to pertussis-toxin-sensitive, guanine-nucleotide-binding proteins and protein kinase C, are involved in eicosanoid secretion by lipopolysaccharide-activated macrophages in response to A23187 and phorbol 12-myristate 13-acetate.

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