Perfluorooctanoate and changes in anthropometric parameters with age in young girls in the Greater Cincinnati and San Francisco Bay Area.

METHODS: We conducted a study of per- and polyfluoroalkyl substance biomarkers, including PFOA, in girls from Greater Cincinnati (CIN, N = 353) and the San Francisco Bay Area (SFBA, N = 351). PFOA was measured in the baseline serum sample collected in 2004-2007 of 704 girls at age 6-8 years. Mixed effects models were used to derive the effect of PFOA on BMI, waist-to-height and waist-to-hip ratios over increasing age in this longitudinal cohort. RESULTS: Median PFOA serum concentrations were 7.3 (CIN) and 5.8 (SFBA) ng/mL, above the U.S. population median for children 12-19 years in 2005-2006 (3.8 ng/mL). Log-transformed serum PFOA had a strong inverse association with BMIz in the CIN girls (p = 0.0002) and the combined two-site data (p = 0.0008); the joint inverse effect of PFOA and Age*PFOA weakened at age at 10-11 years. However, in the SFBA group alone, the relationship was not significant (p = 0.1641) with no evidence of changing effect with age. The effect of PFOA on waist:height ratio was similar to BMIz at both sites, but we did not find a significant effect of PFOA on waist:hip ratio in either the CIN or SFBA girls. CONCLUSIONS: PFOA is associated with decreased BMI and waist:height ratio in young girls, but the strength of the relationship decreases with age. Site heterogeneity may be due to greater early life exposure in Cincinnati. DISCLAIMER: The findings and conclusions in this report are those of the authors and do not necessarily represent the official position of the Centers for Disease Control and Prevention. Use of trade names is for identification only and does not imply endorsement by the CDC, the Public Health Service, or the US Department of Health and Human Services.

Romantic, sexual, and sexual risk behaviours of adolescent females with severe obesity.

BACKGROUND: There is an increasing adolescent population with severe obesity with impairments in social and romantic relationships that are seeking clinical weight management, including weight loss surgery (WLS). OBJECTIVE: To document romantic, sexual and sexual risk behaviours in a clinical sample of adolescent females with severe obesity (BMI > 40 kg/m2 ) compared to those of healthy weight (HW). METHODS: This multi-site study-an ancillary to a prospective longitudinal observational study documenting health in adolescents having WLS-presents pre-operative/baseline data from 108 females undergoing WLS, 68 severely obese seeking lifestyle intervention and 118 of HW. Romantic and sexual risk behaviour and birth control information sources were assessed using the Sexual Activities and Attitudes Questionnaire (SAAQ). RESULTS: Severely obese females reported engaging in fewer romantic and sexual behaviours compared to HW. Similar to HW, a subgroup (25%) of severely females were engaging in higher rates of sexual risk behaviours and reported pregnancies and sexually transmitted infections (STIs). A considerable number (28-44%) reported receiving no birth control information from physicians. CONCLUSIONS: Discussion topics with the adolescent patient should extend beyond reproductive health needs (e.g. contraception, unintended pregnancies) to include guidance around navigating romantic and sexual health behaviours that are precursors to these outcomes.

Phthalate exposure and pubertal development in a longitudinal study of US girls.

STUDY QUESTION: Does phthalate exposure during early childhood alter the timing of pubertal development in girls? SUMMARY ANSWER: Urinary concentrations of high-molecular weight phthalate (high-MWP) metabolites are associated with later pubarche. WHAT IS KNOWN ALREADY: Phthalates are anti-androgenic environmental agents known to alter early development, with possible effects on pubertal onset. STUDY DESIGN, SIZE, AND DURATION: This multi-ethnic study included 1239 girls from New York City, greater Cincinnati, and the San Francisco Bay Area who were 6-8 years old at enrollment (2004-2007) and who were followed until 2011. PARTICIPANTS/MATERIALS, SETTING, METHODS Phthalate metabolites were measured in urine collected at enrollment from 1170 girls; concentrations ranged from <1 to >10,000 µg/l. Breast and pubic hair stages and body size were assessed one to two times annually to determine the age at transition from stage 1 to 2 for breast and pubic hair development. Associations between exposures and pubertal ages were estimated using Cox proportional hazard ratios (HR) with 95% confidence intervals (CI) and survival analyses. Associations were examined with respect to age-specific body mass-index percentile, one of the strongest predictors of pubertal onset. MAIN RESULTS AND THE ROLE OF CHANCE: Urinary concentrations of high-MWP including di(2-ethylhexyl) phthalate (ΣDEHP) metabolites were associated with later pubic hair development during 7 years of observation. The relationship was linear and was stronger among normal-weight girls. Among normal-weight girls, age at pubic hair stage 2 (PH2) was 9.5 months older for girls in the fifth compared with the first quintile of urinary ΣDEHP (medians: 510 and 59 µg/g creatinine, respectively; adjusted HR 0.70, CI 0.53-0.93, P-trend 0.005. Age at first breast development was older for fifth quintile of mono-benzyl phthalate versus first (HR 0.83, CI 0.68-1.02; P-trend 0.018). No associations were observed between low-molecular weight phthalate urinary metabolite concentrations and age at pubertal transition in adjusted analyses. LIMITATIONS, REASONS FOR CAUTION: While there is evidence that phthalate exposures are fairly consistent over time, the exposure measure in this study may not reflect an earlier, more susceptible window of exposure. We investigated alternative explanations that might arise from exposure misclassification or confounding. WIDER IMPLICATIONS OF THE FINDINGS: Phthalates are widespread, hormonally active pollutants that may alter pubertal timing. Whether exposures delay or accelerate pubertal development may depend on age at exposure as well as other factors such as obesity and exposures earlier in life. Whether exposures act independently or as part of real life mixtures may also change their effects on maturation from birth through childhood. STUDY FUNDING/COMPETING INTEREST(S): This project was supported by the US National Institutes of Health, Environmental Protection Agency, New York State Empire Clinical Research Investigator Program and the Avon Foundation. L.H.K. is employed by Kaiser Permanente. The remaining authors declare they have no actual or potential competing financial interests.

Slow conformational changes in MutS and DNA direct ordered transitions between mismatch search, recognition and signaling of DNA repair.

MutS functions in mismatch repair (MMR) to scan DNA for errors, identify a target site and trigger subsequent events in the pathway leading to error removal and DNA re-synthesis. These actions, enabled by the ATPase activity of MutS, are now beginning to be analyzed from the perspective of the protein itself. This study provides the first ensemble transient kinetic data on MutS conformational dynamics as it works with DNA and ATP in MMR. Using a combination of fluorescence probes (on Thermus aquaticus MutS and DNA) and signals (intensity, anisotropy and resonance energy transfer), we have monitored the timing of key conformational changes in MutS that are coupled to mismatch binding and recognition, ATP binding and hydrolysis, as well as sliding clamp formation and signaling of repair. Significant findings include (a) a slow step that follows weak initial interaction between MutS and DNA, in which concerted conformational changes in both macromolecules control mismatch recognition, and (b) rapid, binary switching of MutS conformations that is concerted with ATP binding and hydrolysis and (c) is stalled after mismatch recognition to control formation of the ATP-bound MutS sliding clamp. These rate-limiting pre- and post-mismatch recognition events outline the mechanism of action of MutS on DNA during initiation of MMR.

Cancer incidence in world trade center rescue and recovery workers, 2001-2008.

BACKGROUND: World Trade Center (WTC) rescue and recovery workers were exposed to a complex mix of pollutants and carcinogens. OBJECTIVE: The purpose of this investigation was to evaluate cancer incidence in responders during the first 7 years after 11 September 2001. METHODS: Cancers among 20,984 consented participants in the WTC Health Program were identified through linkage to state tumor registries in New York, New Jersey, Connecticut, and Pennsylvania. Standardized incidence ratios (SIRs) were calculated to compare cancers diagnosed in responders to predicted numbers for the general population. Multivariate regression models were used to estimate associations with degree of exposure. RESULTS: A total of 575 cancers were diagnosed in 552 individuals. Increases above registry-based expectations were noted for all cancer sites combined (SIR = 1.15; 95% CI: 1.06, 1.25), thyroid cancer (SIR = 2.39; 95% CI: 1.70, 3.27), prostate cancer (SIR = 1.21; 95% CI: 1.01, 1.44), combined hematopoietic and lymphoid cancers (SIR = 1.36; 95% CI: 1.07, 1.71), and soft tissue cancers (SIR = 2.26; 95% CI: 1.13, 4.05). When restricted to 302 cancers diagnosed ≥ 6 months after enrollment, the SIR for all cancers decreased to 1.06 (95% CI: 0.94, 1.18), but thyroid and prostate cancer diagnoses remained greater than expected. All cancers combined were increased in very highly exposed responders and among those exposed to significant amounts of dust, compared with responders who reported lower levels of exposure. CONCLUSION: Estimates should be interpreted with caution given the short follow-up and long latency period for most cancers, the intensive medical surveillance of this cohort, and the small numbers of cancers at specific sites. However, our findings highlight the need for continued follow-up and surveillance of WTC responders.

Application of stopped-flow kinetics methods to investigate the mechanism of action of a DNA repair protein.

Transient kinetic analysis is indispensable for understanding the workings of biological macromolecules, since this approach yields mechanistic information including active site concentrations and intrinsic rate constants that govern macromolecular function. In case of enzymes, for example, transient or pre-steady state measurements identify and characterize individual events in the reaction pathway, whereas steady state measurements only yield overall catalytic efficiency and specificity. Individual events such as protein-protein or protein-ligand interactions and rate-limiting conformational changes often occur in the millisecond timescale, and can be measured directly by stopped-flow and chemical-quench flow methods. Given an optical signal such as fluorescence, stopped-flow serves as a powerful and accessible tool for monitoring reaction progress from substrate binding to product release and catalytic turnover(1,2). Here, we report application of stopped-flow kinetics to probe the mechanism of action of Msh2-Msh6, a eukaryotic DNA repair protein that recognizes base-pair mismatches and insertion/deletion loops in DNA and signals mismatch repair (MMR)(3-5). In doing so, Msh2-Msh6 increases the accuracy of DNA replication by three orders of magnitude (error frequency decreases from approximately 10(-6) to 10(-9) bases), and thus helps preserve genomic integrity. Not surprisingly, defective human Msh2-Msh6 function is associated with hereditary non-polyposis colon cancer and other sporadic cancers(6-8). In order to understand the mechanism of action of this critical DNA metabolic protein, we are probing the dynamics of Msh2-Msh6 interaction with mismatched DNA as well as the ATPase activity that fuels its actions in MMR. DNA binding is measured by rapidly mixing Msh2-Msh6 with DNA containing a 2-aminopurine (2-Ap) fluorophore adjacent to a G:T mismatch and monitoring the resulting increase in 2-aminopurine fluorescence in real time. DNA dissociation is measured by mixing pre-formed Msh2-Msh6 G:T(2-Ap) mismatch complex with unlabeled trap DNA and monitoring decrease in fluorescence over time(9). Pre-steady state ATPase kinetics are measured by the change in fluorescence of 7-diethylamino-3-((((2-maleimidyl)ethyl)amino)carbonyl) coumarin)-labeled Phosphate Binding Protein (MDCC-PBP) on binding phosphate (Pi) released by Msh2-Msh6 following ATP hydrolysis(9,10). The data reveal rapid binding of Msh2-Msh6 to a G:T mismatch and formation of a long-lived Msh2-Msh6 G:T complex, which in turn results in suppression of ATP hydrolysis and stabilization of the protein in an ATP-bound form. The reaction kinetics provide clear support for the hypothesis that ATP-bound Msh2-Msh6 signals DNA repair on binding a mismatched base pair in the double helix. F

Mechanism of cadmium-mediated inhibition of Msh2-Msh6 function in DNA mismatch repair.

The observation that Cadmium (Cd(2+)) inhibits Msh2-Msh6, which is responsible for identifying base pair mismatches and other discrepancies in DNA, has led to the proposal that selective targeting of this protein and consequent suppression of DNA repair or apoptosis promote the carcinogenic effects of the heavy metal toxin. It has been suggested that Cd(2+) binding to specific sites on Msh2-Msh6 blocks its DNA binding and ATPase activities. To investigate the mechanism of inhibition, we measured Cd(2+) binding to Msh2-Msh6, directly and by monitoring changes in protein structure and enzymatic activity. Global fitting of the data to a multiligand binding model revealed that binding of about 100 Cd(2+) ions per Msh2-Msh6 results in its inactivation. This finding indicates that the inhibitory effect of Cd(2+) occurs via a nonspecific mechanism. Cd(2+) and Msh2-Msh6 interactions involve cysteine sulfhydryl groups, and the high Cd(2+):Msh2-Msh6 ratio implicates other ligands such as histidine, aspartate, glutamate, and the peptide backbone as well. Our study also shows that cadmium inactivates several unrelated enzymes similarly, consistent with a nonspecific mechanism of inhibition. Targeting of a variety of proteins, including Msh2-Msh6, in this generic manner would explain the marked broad-spectrum impact of Cd(2+) on biological processes. We propose that the presence of multiple nonspecific Cd(2+) binding sites on proteins and their propensity to change conformation on interaction with Cd(2+) are critical determinants of the susceptibility of corresponding biological systems to cadmium toxicity.

Intra-arterial injection of dissolved flunitrazepam tablets.

Intra-arterial application of dissolved tablets is associated with a high risk of tissue necrosis. An early active vasodilatating and recanalising treatment is necessary. We present the case of 21-year-old female who applied three dissolved Flunitrazepam tablets into the ulnar artery and was successfully treated with prostaglandin E1 and recombinant tissue plasminogen activator.

Value of transesophageal echocardiography, esophago-gastroduodenoscopy and retinoscopy prior to intra-arterial fibrinolytic therapy in patients with peripheral arterial disease.

BACKGROUND: We prospectively investigated the need for esophagogastroduodenoscopy (EGD), transesophageal echocardiography (TEE) and retinoscopy for pre-interventional screening in patients with peripheral arterial occlusive disease (PAD) prior to intraarterial fibrinolytic therapy. PATIENTS AND METHODS: 212 consecutive patients suffering from PAD (164 male and 48 female, mean age: 64 +/- 11 years, 161 patients stage II of Fontaine's classification, 10 patients at stage III and 41 patients at stage IV) referred for interventional treatment were included. 173 EGDs, 169 TEEs and 188 retinoscopies were performed within one week prior to fibrinolysis. 114 patients had all three examinations. RESULTS: Pathologic findings were detected in 56 (49%) of the 114 patients: 23 erosions, 12 ulcers, 2 esophagites, 1 gastric carcinomata, 3 intracardiac thrombi, 5 aortic thrombi, 11 diabetic and 5 hypertensive retinopathies and 1 with retinal aneurysms. 30 patients (25%) received fibrinolytic therapy, despite a contraindication: The one patient with ventricular thrombus was treated as an ultimate therapy, and amputation was prevented. Two patients showing plaques covered by large thrombi in the descending thoracic aorta were treated because cranial embolism should not occur. Four diabetic patients with multilevel disease, severe claudication and prior retinal bleeding were treated. Fibrinolytic therapy was started on 23 patients after complete healing of the mucosal lesions. CONCLUSION: TEE revealed potential sources of embolization in 4% of the patients and is justified to reduce the individual risk. Retinoscopy should be done in patients with diabetes mellitus and hypertension, and if prior bleeding is present fibrinolysis should be done only if other treatment-regimes are not available.

Exploring the relationship between timing of menarche and eating disorder symptoms in Black and White adolescent girls.

OBJECTIVE: This study examined the relationship between timing of sexual maturation and eating disorders symptoms in adolescent girls. METHOD: Data were collected over 10 years for a cohort of 1,213 Black girls and 1,166 White girls who were either 9 or 10 years old at study entry. Annually, girls' height and weight were measured and, biannually, girls completed self-report measures of eating disorders symptoms. RESULTS: Early-onset menarche is a risk factor for the development of body image and dieting concerns, but the effect of timing is due to the impact of early and late maturation on body weight. DISCUSSION: Findings underscore the importance of adiposity as a risk factor for poor mental health.

A preliminary examination of adolescent girls' perceptions of the parental knowledge of their boyfriends.

STUDY OBJECTIVE: The purpose of this study was to describe adolescent girls' perceptions of their parents' contact with and knowledge of the girls' boyfriends. A second objective was to determine if knowledge was related to demographic characteristics of the girls or aspects of the relationship with their boyfriend. DESIGN: Cross-sectional analysis of data from an interview with adolescent girls enrolled in a longitudinal study. SETTING: Urban adolescent medicine clinic. PARTICIPANTS: Adolescent girls (n = 109) with a mean age of 17.6 (range 14.9-19.3 yr). Eighty percent were African-American and 20% were Caucasian. RESULTS: Most girls reported that their parents had some contact (either in person or on the phone) with their boyfriends. Thirteen girls reported that their parents did not know their boyfriends well, 40 reported that their parents knew their boyfriends somewhat, and 56 reported that their parents knew their boyfriends well. Age, race, and sexual experience were not related to how well the parents knew the boyfriend. Girls who had been involved with their boyfriends longer, believed that their relationship would last longer, were more satisfied, were more likely to tell their boyfriends private information and were more likely to describe their parents as knowing their boyfriends well. CONCLUSIONS: These results provide an initial description of girls' perceptions of their parents' relationships with their boyfriends. It would be important to understand how to utilize the information regarding these parental-boyfriend relationships to further adolescent girls' development of healthy (both psychologically and physically) relationships.

Drug treatment of nonviral sexually transmitted diseases: specific issues in adolescents.

Sexually transmitted diseases (STDs) are common and happen more frequently in younger patients. These adolescents have unique risks of acquiring infection because of developing psychosocial skills, biological factors and sociocultural barriers. The clinician must be adept at identifying and modifying these risks through knowledge of the adolescent stages of development and biology, with good history and examination skills that make teens comfortable during their evaluation, and with patient education and treatment. Whereas patient compliance and partner notification can be problematic in any population, teenagers may be more prone not to follow through on these issues. While compliance may notbe as important as previously thought, there is a dearth of studies of patient compliance and STD treatment in adolescents. Guidelines for the treatment of STDs were published by the Centers for Disease Control and Prevention (CDC) in 1998 and the Medical Society for the Study of Venereal Diseases in 1999. Most of the data obtained to formulate these guidelines were not necessarily adolescent specific and few studies, if any, have included adolescent patients since the CDC document was published. In the treatment of chlamydia, it appears that even with relative noncompliance with the 7-day regimen of doxycycline, it is as effective as single dose azithromycin. This has implications in cost control, important for centres with limited funds for treatment. While fluoroquinolone-resistant gonorrhoea has been reported for some time, the number of reports in the US is increasing, with a recent report of decreased susceptibility to azithromycin. As many studies have shown efficacy with single agent therapy with azithromycin in combined gonococcal and chlamydial infection, one must view these new resistance data with concern and give serious consideration to dual agent treatment, especially in the locale of the practitioner. Also, fluoroquinolone use is not advised in patients under the age of 18 years at present because of concerns of adverse effects on cartilage. While not much has changed from the 1998 guidelines for most of the other STDs, there seems to be a general trend in treating pelvic inflammatory disease (PID) on an outpatient basis if good follow-up is assured, even in the adolescent population. There is still debate on whether anaerobe coverage is needed in PID without tubo-ovarian abscess or other complications. One other update includes the use of daily metronidazole gel instead of twice daily usage in the treatment of bacterial vaginosis. With the lack of studies specific to adolescents, it is left up to the clinician to tailor the treatment of adolescents on the basis of current guidelines and patient preferences.

Sexual initiation: predictors and developmental trends.

BACKGROUND: Early initiation of sexual intercourse is associated with increased risk for acquiring sexually transmitted diseases. GOAL: To examine variables related to sexual initiation and developmental changes in the reasons why adolescent girls have sexual intercourse. STUDY DESIGN: A longitudinal study of girls recruited from an adolescent medicine clinic was performed. RESULTS: Logistic regression showed that girls who described their families as being expressive, having a moral-religious emphasis, providing supervision, and having greater maternal education, and who experienced menarche at an older age were older at sexual initiation. On the basis of contingency analyses, younger girls were less likely to report attraction or love, and more likely to report peers having sex as a reason for sexual intercourse at initiation. A generalized estimating equation analysis indicated that girls at younger ages are more likely to report curiosity, a grown-up feeling, partner pressure, and friends having sexual intercourse as reasons for intercourse. Girls at older ages are more likely to report a feeling of being in love, physical attraction, too excited to stop, drunk or high partner, and feeling romantic as reasons for having sexual intercourse. CONCLUSIONS: Prevention programs should include a focus on familial characteristics and susceptibility to peer norms. They should be conducted with sensitivity to the developmental changes in intimate relationships that occur during adolescence.

Adolescent girl's coping with an STD. Not enough problem solving and too much self-blame.

STUDY OBJECTIVE: Approximately three million teenagers are infected with an STD each year. The ways in which an adolescent girl copes with an STD may have implications for future risk and for psychological adjustment. The purpose of the current study was to compare whether coping with an STD was similar to coping with other stressors. SETTING: Urban, hospital-based adolescent medicine clinic. DESIGN AND PARTICIPANTS: Sixty-seven girls with a mean age of 15.9 (sexual debut was 13.8) yr completed the KIDCOPE in response to both an STD acquisition and an interpersonal stressor within the previous 6 months. RESULTS: Problem solving was used less often, and self-blame was used more often, in response to an STD acquisition. Frequency of use of self-blame was not correlated with perceived helpfulness. CONCLUSIONS: These findings suggest that clinicians need to help adolescent girls manage STD acquisition from the perspective of problem solving rather than self-blame.

Impact of timing of pubertal maturation on growth in black and white female adolescents: The National Heart, Lung, and Blood Institute Growth and Health Study.

OBJECTIVES: To evaluate the impact of early, mid-onset, and late maturation, as assessed by timing of menarche, on height, height velocity, weight, body mass index, and sum of skinfolds in a group of white and black girls. STUDY DESIGN: The Growth and Health Study recruited 9- and 10-year-old girls from Richmond, California, Cincinnati, Ohio, and Washington, DC. There were 616 white and 539 black participants recruited at age 9 and 550 white and 674 black participants recruited at age 10. Participants were seen annually for 10 visits. Longitudinal regression models were used to test for differences in each growth measure by timing of menarche across all ages and to determine whether these differences change with age. RESULTS: Mean age at menarche among white participants was 12.7 years, and among black participants, 12.0 years. According to race-specific 20th and 80th percentiles, early maturers were tallest at early ages and shortest after adult stature had been attained. Peak height velocity and post-menarche increment in stature were greatest in early maturers and least in late maturers. Weight was greatest in early and least in late maturers, as was body mass index. Sum of skinfolds was also greatest in early and least in late maturers. There was no impact of timing of maturation on two common measures of regional fat distribution. CONCLUSIONS: Girls who matured early were shorter in early adulthood, despite having greater peak height velocity and post-menarchal increment in height. Throughout puberty, early maturers had greater ponderosity and adiposity, although there was no association with regional distribution of fat.

Racial differences in accuracy of self-assessment of sexual maturation among young black and white girls.

PURPOSE: To examine the validity of maturation self-assessments and to investigate the association between race and validity of self-assessments among young black and white girls. METHODS: Self-assessments and examiner-assessments of areolar and pubic hair development using line drawings were compared at three visits among a cohort of 11- to 14-year-old girls enrolled in the National Heart, Lung, and Blood Institute's Growth and Health Study. Accuracy rates and kappa coefficients were calculated to measure the agreement between girls and examiners. Logistic regression models were used to assess the racial differences in the accuracy of self-assessments while adjusting for possible confounders. RESULTS: Fair to moderate agreement was found between self- and examiner-assessments (areolar self-assessments: adjusted accuracy rates: 60.7-69.9%, kappa: 0.32-0.51; pubic hair self-assessments: adjusted accuracy rates: 57.9-70.7%, kappa: 0.36-0.55). While there were indications of racial differences in the ability to perform self-assessment with black girls tending to self-assess less accurately, most of the differences disappeared after adjusting for nurse-assessed stage. CONCLUSIONS: These findings suggest that self-assessment can substitute for examiner evaluations only when crude estimates of maturation are needed. However, when accurate maturation stage data are required, examiner-assessments are necessary. Because black girls are usually more pubertally advanced and tend to underestimate their development, the value of self-assessment is questionable for assessing populations with young black and white girls. Use of self-assessment might present biased estimates of maturation and confound research findings.

The prevalence of upper lip hair in black and white girls during puberty: a new standard.

In order to develop standards for upper lip hair in adolescent girls, 4693 observations in 856 black and white subjects were made over 9 years. Up to 2 years after menarche, 90% of girls had no upper lip hair. More than 2 years after menarche, 48.8% of black girls and 9.0% of white girls had small amounts of upper lip hair. This may be more significant in adolescent girls than in older women.

Techniques of testing for sexually transmitted diseases.

Adolescent and young adult women are the highest-risk group for nearly all sexually transmitted infections. This article reviews diagnostic methods for the most common bacterial and viral sexually transmitted infections, with special attention to the use of nucleic acid amplification methods, as well as the utilization of nontraditional clinical specimens. These new modalities should help the care provider identify and manage the large asymptomatic pool of infected patients, and further lower the prevalence and burden of infection.

Estradiol and testosterone effects on lipids in black and white boys aged 10 to 15 years.

Previous studies of lipids in adolescent males have shown greater increases in triglycerides and decreases in high-density lipoprotein cholesterol (HDL-C) in white boys compared with black boys, significant correlations between sex hormones and lipids, and complex body mass index (BMI) hormone-lipid associations. Within this frame of reference, we assessed race, BMI, and sex hormones as predictors of lipid parameters in 536 black and white boys recruited from area schools. Black boys were more advanced in puberty than white boys. After adjusting for pubertal stage, estradiol (E2) levels were higher in black boys but free testosterone (T) levels did not differ. Age, pubertal stage, race, BMI, free T, and E2 were entered as explanatory variables for lipids in backward stepwise regression analyses. The BMI and race were retained in every model. Black boys had lower triglycerides and apolipoprotein B (apo B) and higher HDL-C. E2 was inversely associated with total cholesterol (TC), triglycerides, low-density lipoprotein cholesterol (LDL-C), apo B, and the LDL-C/HDL-C ratio. Free T was inversely associated with HDL-C and positively associated with apo B. Given the increases in free T and E2 during adolescence and the association of these hormones with both atherogenic and protective lipid parameters, racial differences in E2 could contribute to the more atherogenic lipid profile found in white boys after puberty.

Longitudinal risk of std acquisition in adolescent girls using a generalized estimating equations model

Background: To date, few studies have used a longitudinal approach in examining risk factors for STD acquisition in teenage girls. In the present study, we examined risk of STD acquisition in adolescent girls over a three-year period using longitudinal analyses.Methods: One hundred and seventy-four girls between the ages of 12 and 16 (mean age = 14.5) participated in a longitudinal study of adolescent romantic relationships. The racial composition of the subject pool was 80% African-American and 20% Caucasian. These girls were followed for three years at six-month intervals. By the end of the study, 127 of the girls were sexually experienced, and thus, were included in the analyses regarding risk for STDs. The risk for history of STD was evaluated using a generalized estimating equations (GEE) model, which allows for the inclusion of data from subjects with missing visits. The following independent variables were entered into the model: age, race, screening IQ score, qualitative cognitive functioning, perceptions of STD prevalence among female friends, and whether a condom was used at last intercourse. Additional independent variables included number of lifetime partners (4 or more lifetime partners, 2 to 3 lifetime partners, only one partner) and age of sexual debut (less than 14 years, 14-16 years, and 17 years and older), five factors from the Family Environment Scale, and three types of parental monitoring (direct, direct when with peers, and indirect).Results: The results of the longitudinal (GEE) model indicated that having a history of an STD was significantly related to a younger age of sexual debut (p <.01), having more partners (p <.0001), being African-American (p =. 01), and having a lower screening IQ score (p <.01).Conclusions: These results suggest that risk of STD is associated with both modifiable and non-modifiable variables. Race and intellectual functioning independently contributed to STD risk, stressing the importance of utilizing prevention programs that are culturally and developmentally specific. For example, less intelligent girls may need to have information presented in a more concrete manner, with a focus on the present rather than the future. The targets of these prevention programs should continue to emphasize delaying initiation, as well as partner selection. Finally, the fact that variables for STD acquisition in this longitudinal model are comparable to previous cross-sectional studies of STD acquisition suggests that these are potent predictors of risk.