Confidentiality Discussions and Private Time With a Health-Care Provider for Youth,United States, 2016

Purpose

The objective of the study was to define factors associated with adolescent and young adult (AYA) experiences with private time and having discussed confidentiality and the impact of these experiences on improving delivery of clinical preventive services.

Gastric schwannoma. A case diagnosed by puncture biopsy]

One case of schwannoma of the stomach diagnosed with ultrasound-guided biopsy puncture is reported. This diagnosis is usually not established with radiographic and endoscopic examinations. A preoperative diagnosis allows partly predicting the type of exeresis to be performed. On the other hand, guided biopsy puncture seldom allows establishing a prognosis, for which the criteria are based on the analysis of the whole tumor and the possible discovery of synchronous or metachronous metastases.     

Schedule-dependent antitumor and toxic effects of thymidine and 5-fluorouracil in AKR and L1210 leukemias

Summary The effect of thymidine (dThd) on 5-fluorouracil (FUra) toxicity to both leukemia stem cells (LCFU) and hematopoietic stem cells (NCFU) was examined. A dose of 10 mg/mouse of dThd given within 1 h before FUra enhanced FUra cytotoxicity to NCFU by a factor of about 4. This effect was also reflected in the reduction of the LD₁₀. The dose-survival curve of FUra in AKR leukemia was modified by the prior administration of dThd 10 mg/mouse: the cytotoxic effect of FUra was enhanced by a factor of between 100 and 1000 throughout the dose range studied. These findings were reflected in the ILS studies. When given by high dose infusion dThd had only a slight antitumor effect on AKR leukemia, and no effect on L1210. When large doses of dThd were infused concomitantly with FUra they ptoentiated its cytotoxicity against NCFU, AKR LCFU, and L1210 LCFU in a dose-dependent manner and by a maximum factor of about 70.This investigation was supported by PHS grant no CA-34144 awarded by the National Cancer Institute, DHSS     

Sexually transmitted diseases, unintended pregnancy, and adolescent health promotion

Adolescence is a critical period in the development of sexual behaviors that may lead to acquiring sexually transmitted diseases (STDs), including human immunodeficiency virus (HIV), and to unintended pregnancy. Understanding adolescent sexual behavior is essential for understanding adolescents' risk of pregnancy and STD/HIV infection and for planning and evaluating health promotion activities. This chapter reviews the sexual behaviors and psychosocial factors associated with STDs and unintended pregnancy among adolescents as well as school-, community-, and clinic-based interventions designed to reduce risk behaviors and promote adolescent sexual health.     

Initiation of sexual intercourse among middle school adolescents: the influence of psychosocial factors.

PURPOSE: To explore potential psychosocial predictors for initiation of sexual intercourse among middle-school, inner-city youth, using longitudinal data from the Healthy and Alive! project. METHODS: We conducted hierarchical, logistic regression with adjustment for intraclass correlation over two sequential periods, including seventh and eighth grades (N = 3163), to assess the independent influence of psychosocial and demographic factors. Internally reliable scales to assess psychosocial influences were created, based on major theories of behavior. The sample was 52% female, 51% black, 30% Hispanic, 9% white, and 3% Asian. At baseline, 13% of girls and 39% of boys reported already having initiated sexual intercourse. RESULTS: Personal and perceived peer norms about refraining from sex were a strong and consistent protective factor. Alcohol and other drug use, poor academic performance, male gender, and black race were consistent risk factors. Self-efficacy showed a mixed effect: protective in the seventh grade but increasing risk in the eighth grade. Speaking a language other than English was a protective factor in seventh grade. Both psychosocial and demographic factors provided independent explanatory power. CONCLUSIONS: Psychosocial factors, particularly norms about having sex, influence initiation of sexual intercourse. These data suggest that programs to delay initiation of sexual intercourse should reinforce norms about refraining from sex.     

Mn(II) oxidation by an ascomycete fungus is linked to superoxide production during asexual reproduction

Manganese (Mn) oxides are among the most reactive minerals within the environment, where they control the bioavailability of carbon, nutrients, and numerous metals. Although the ability of microorganisms to oxidize Mn(II) to Mn(III/IV) oxides is scattered throughout the bacterial and fungal domains of life, the mechanism and physiological basis for Mn(II) oxidation remains an enigma. Here, we use a combination of compound-specific chemical assays, microspectroscopy, and electron microscopy to show that a common Ascomycete filamentous fungus, Stilbella aciculosa, oxidizes Mn(II) to Mn oxides by producing extracellular superoxide during cell differentiation. The reactive Mn oxide phase birnessite and the reactive oxygen species superoxide and hydrogen peroxide are colocalized at the base of asexual reproductive structures. Mn oxide formation is not observed in the presence of superoxide scavengers (e.g., Cu) and inhibitors of NADPH oxidases (e.g., diphenylene iodonium chloride), enzymes responsible for superoxide production and cell differentiation in fungi. Considering the recent identification of Mn(II) oxidation by NADH oxidase-based superoxide production by a common marine bacterium (Roseobacter sp.), these results introduce a surprising homology between some prokaryotic and eukaryotic organisms in the mechanisms responsible for Mn(II) oxidation, where oxidation appears to be a side reaction of extracellular superoxide production. Given the versatility of superoxide as a redox reactant and the widespread ability of fungi to produce superoxide, this microbial extracellular superoxide production may play a central role in the cycling and bioavailability of metals (e.g., Hg, Fe, Mn) and carbon in natural systems.     

Noncoital sexual activities among adolescents

PURPOSE: Although prior research has demonstrated that many adolescents engage in noncoital sexual behavior, extant peer-reviewed studies have not used nationally representative data or multivariate methods to examine these behaviors. We used data from Cycle 6 of National Survey of Family Growth (NSFG) to explore factors related to oral and anal sex among adolescents. METHODS: Data come from 2,271 females and males aged 15-19 in 2002. Computer-assisted self-administered interviews were used to collect sensitive information, including whether respondents had ever engaged in vaginal, oral or anal sex. We used t tests and multivariate logistic regression to test for differences and identify independent characteristics associated with experience with oral or anal sex. RESULTS: In all, 54% of adolescent females and 55% of adolescent males have ever had oral sex, and one in 10 has ever had anal sex. Both oral sex and anal sex were much more common among adolescents who had initiated vaginal sex as compared with virgins. The initiations of vaginal and oral sex appear to occur closely together; by 6 months after first vaginal intercourse, 82% of adolescents also engaged in oral sex. The strongest predictor of anal sex involvement was time since initiation of vaginal sex and the likelihood of anal sex increased with greater time since first vaginal intercourse. Teens of white ethnicity and higher socioeconomic status were more likely than their peers to have ever had oral or anal sex. CONCLUSIONS: Health professionals and sexual health educators should address noncoital sexual behaviors and risk for sexually transmitted infections risk, understanding that noncoital behaviors commonly co-occur with coital behaviors.     

The association of sexual behaviors with socioeconomic status, family structure, and race/ethnicity among US adolescents

OBJECTIVES: This study assessed the relation of socioeconomic status (SES), family structure, and race/ethnicity to adolescent sexual behaviors that are key determinants of pregnancy and sexually transmitted diseases (STDs). METHODS: The 1992 Youth Risk Behavior Survey/Supplement to the National Health Interview Survey provided family data from household adults and behavioral data from adolescents. RESULTS: Among male and female adolescents, greater parental education, living in a 2-parent family, and White race were independently associated with never having had sexual intercourse. Parental education did not show a linear association with other behaviors. Household income was not linearly related to any sexual behavior. Adjustment for SES and family structure had a limited effect on the association between race/ethnicity and sexual behaviors. CONCLUSIONS: Differences in adolescent sexual behavior by race and SES were not large enough to fully explain differences in rates of pregnancy and STD infection. This suggests that other factors, including access to health services and community prevalence of STDs, may be important mediating variables between SES and STD transmission and pregnancy among adolescents.     

Synchronous growth and aging of Caenorhabditis elegans in the presence of fluorodeoxyuridine.

Fluorodeoxyuridine (FUdR), an inhibitor of DNA synthesis, was examined for its ability to prevent a synchronous population of C. elegans from reproducing without otherwise interfering with the organism's post-maturational development and aging. When a synchronized population was exposed to 400 micrometer FUdR just as the population reached sexual maturity, the FUdR induced complete sterility within five hours by preventing eggs from hatching. Any larvae that hatched from eggs made before the FUdR was added remained small in the presence of FUdR and were easily removed by filtration or sedimentation. FUdR-sterilized adults showed no morphological abnormalities. Age-associated changes seen in controls also occurred in FUdR-treated worms, including atrophy of the gonads, increased pigmentation, sluggishness and increased transparency. Life span was not shortened by FUdR treatment. Our observations suggest that treatment with FUdR under carefully controlled conditions is a reasonable way to maintain synchronously aging populations of C. elegans.