bluuebunny/crossref_metadata_2025_split huggingface dataset:
In men older than 70 years, total testosterone remains stable while free testosterone declines with age. The Health in Men Study
Authors: Yeap Bu B , Almeida Osvaldo P , Hyde Zoë , Norman Paul E , Chubb S A Paul , Jamrozik Konrad , Flicker Leon 
Published: April 2007

Objective: An age-related decline in serum total and free testosterone concentration may contribute to ill health in men, but limited data are available for men > 70 years of age. We sought to determine the distribution and associations of reduced testosterone concentrations in older men.
Design: The Health in Men Study is a community-representative prospective cohort investigation of 4263 men aged ≥ 70 years. Cross-sectional hormone data from 3645 men were analysed.
Methods: Early morning sera were assayed for total testosterone, sex hormone binding globulin (SHBG) and LH. Free testosterone was calculated using the Vermeulen method.
Results: Mean (± s.d.) serum total testosterone was 15.4 ± 5.6 nmol/l (444 ± 162 ng/dl), SHBG 42.4 ± 16.7 nmol/l and free testosterone 278 ± 96 pmol/l (8.01 ± 2.78 ng/dl). Total testosterone correlated with SHBG (Spearman’s r = 0.6, P < 0.0001). LH and SHBG increased with age (r = 0.2, P < 0.0001 for both). Instead of declining, total testosterone increased marginally (r = 0.04, P = 0.007) whilst free testosterone declined with age (r = −0.1, P < 0.0001). Free testosterone was inversely correlated with LH (r = −0.1, P < 0.0001). In multivariate analyses, increasing age, body mass index (BMI) and LH were associated with lower free testosterone.
Conclusions: In men aged 70–89 years, modulation of androgen action may occur via an age-related increase in SHBG and reduction in free testosterone without a decline in total testosterone concentration. Increasing age, BMI and LH are independently associated with lower free testosterone. Further investigation would be required to assess the clinical consequences of low serum free testosterone, particularly in older men in whom total testosterone may be preserved.
The sex-specific association of serum osteoprotegerin and receptor activator of nuclear factor κB legend with bone mineral density in older adults: the Rancho Bernardo Study
Authors: Stern Anna , Laughlin Gail A , Bergstrom Jaclyn , Barrett-Connor Elizabeth 
Published: April 2007

Objective: The role of osteoprotegerin (OPG) and its receptor activator of nuclear factor κB legend (RANKL) in the regulation of bone in humans remain unclear. We examined the sex-specific associations of serum OPG, RANKL, and their ratio with bone mineral density (BMD) in older adults.
Design: Participants were 681 community-dwelling adults, ages 45–90 years, who had serum OPG and RANKL measured and bone density scans in 1988–1991, with follow-up scans 5 and/or 10 years later.
Methods: Analyses were sex-specific; women using and not using estrogen were evaluated separately. Cross-sectional analyses used multivariable regression models; longitudinal analyses used repeated measures mixed effects models.
Results: In cross-sectional analyses, age- and weight-adjusted serum OPG levels were significantly positively associated with BMD at the lumbar spine in men, and at the femoral neck, total hip, and lumbar spine in women using estrogen, but not in non-users of estrogen. RANKL concentrations were significantly and inversely associated with BMD in men only, and at the total hip. Neither OPG nor RANKL was significantly associated with bone loss. Results for the RANKL/OPG ratio were the same as those for RANKL alone.
Conclusions: These results suggest a modulatory effect of both endogenous and exogenous sex hormones on the biologic interaction of OPG, RANKL, and bone.
Changes in Prevalence of HIV Infection and Sexual Risk Behavior in Men Who Have Sex With Men in San Francisco: 1997–2002
Authors: Osmond Dennis H. , Pollack Lance M. , Paul Jay P. , Catania Joseph A. 
Published: April 2007

Objectives. We assessed differences in HIV prevalence and sexual risk behavior among men who have sex with men (MSM) between 1997 and 2002 in San Francisco. Methods. We used 2 population-based random-digit-dial telephone surveys of MSM households in San Francisco in 1997 (n=915) and 2002 (n=879). Results. Estimated HIV prevalence increased from 19.6% in 1997 to 26.8% in 2002. Measures of sexual risk also increased. Unprotected anal intercourse with a partner of different or unknown HIV serostatus increased from 9.3% to 14.6%. Mean number of male partners increased from 10.7 to 13.8. The largest reported increase was 18.9% to 26.8% for “serosorting,” or choosing unprotected anal intercourse partners believed to have the same HIV serostatus as oneself. Men aged 30 to 50 reported the largest increase in unprotected anal intercourse, whereas men aged 18 to 29 reported the largest increase in serosorting. Changes in the age distribution did not explain the increase in risky behavior. Conclusions. Both HIV prevalence and sexual risk increased substantially among MSM in San Francisco between 1997 and 2002. Serosorting is being adopted more frequently than condom use by young MSM, but its effectiveness as a harm reduction strategy is not known.
Managing Medicare’s HIV Caseload in the Era of Suppressive Therapy
Authors: Gilden David E. , Kubisiak Joanna M. , Gilden Daniel M. 
Published: April 2007

Objectives. The 1996 introduction of antiretroviral medications changed Medicare’s role in providing HIV care. We analyzed Medicare’s patient database in an effort to document the new HIV therapies’ effects on expenditures and outcomes. Methods. We examined the medical billing records of a 5% national Medicare sample from 1997 through 2003. The cohort was stratified by year and categorized by age, race/ethnicity, gender, and Medicare status. Population summaries were categorized according to presence of major chronic diseases and HIV-related conditions. Results. The number of Medicare beneficiaries with HIV increased from 42520 in 1997 to 76500 in 2003, whereas mortality among this group fell by 35%. HIV-associated infections declined by as much as 43% (mycoses). Heart and liver disease and diabetes increased by more than 50%. Adjusted annual per person Medicare expenditures fell 28%; expenditures were 49% higher for Blacks than for Whites. Conclusions. Improved HIV medical management has led to fewer deaths and has shifted treatment toward chronic care. However, successful management is complicated by conditions that have not been historically linked to HIV and whose effects vary according to race/ethnicity.
History of Childhood Sexual Abuse and HIV Risk Behaviors in Homosexual and Bisexual Men
Authors: Brennan David J. , Hellerstedt Wendy L. , Ross Michael W. , Welles Seth L. 
Published: April 2007

Objectives. We examined the prevalence and frequency of childhood sexual abuse and their association with sexual risk among a sample of gay and bisexual men. Methods. Cross-sectional data were collected by survey from randomly selected gay and bisexual men who attended the 1997 and 1998 Minneapolis/St. Paul Gay, Lesbian, Bisexual, and Transgender Pride Festivals. Data included demographics, sexual activity, history of childhood sexual abuse, HIV status, history of sexually transmitted infection, use of sex-related drugs (such as crack, cocaine, Ecstasy, amyl nitrate, crystal methamphetamine, and Special K), and history of exchanging sex for payment. Results. childhood sexual abuse was reported by 15.5% of the survey respondents (n = 134). Those who reported experiencing abuse regularly were more likely to (1) be HIV positive, (2) have exchanged sex for payment, and (3) be a current user of sex-related drugs. Neither unsafe sex nor sexually transmitted infections were associated with childhood sexual abuse. Conclusions. These findings show that more than 1 in 7 gay and bisexual men in a non-clinical, festival-based setting were victims of childhood sexual abuse and that childhood sexual abuse was associated with alarmingly high rates of men who were HIV infected and antecedent risk behaviors.
Reproductive Health of Adolescent Girls Perinatally Infected With HIV
Authors: Brogly Susan B. , Watts D. Heather , Ylitalo Nathalie , Franco Eduardo L. , Seage George R. , Oleske James , Eagle Michelle , Van Dyke Russell 
Published: April 2007

Objectives. We sought to describe the reproductive health of adolescent girls perinatally infected with HIV. Methods. We estimated the incidence of first pregnancy, genital infections, and abnormal cervical cytology for 638 girls aged 13 years and older in the Pediatric AIDS Clinical Trials Group protocol 219C. Results. Thirty-eight girls became pregnant, for a first pregnancy rate of 18.8/ 1000 person-years; 7 of these girls had additional pregnancies (95% confidence interval [CI]=13.3, 25.7). Thirty-two pregnancies resulted in live births. All girls received antiretroviral therapy during pregnancy. One infant was HIV infected, 29 were uninfected, and 2 had unknown infection status, for a rate of mother-to-child transmission of HIV in infants with known infection status of 3.3% (95% CI=0.1, 18.6). Condylomata and trichomoniasis were the most frequent genital infections. Forty-eight (47.5%) of 101 girls with Papanicolaou test examinations had abnormal cervical cytology, including atypical cells of undetermined significance (n=18), low-grade squamous intraepithelial lesions (SIL; n=27), and high-grade SIL (n=3). Many abnormalities persisted despite intervention. Conclusions. Pregnancy rates were lower and cervical abnormalities were higher than among non–HIV-infected adolescents. These findings underscore the importance of Papanicolaou tests and promotion of safer sexual practices in this population.
Prevalence of HIV Infection and Predictors of High-Transmission Sexual Risk Behaviors Among Men Who Have Sex With Men
Authors: Schwarcz Sandra , Scheer Susan , McFarland Willi , Katz Mitchell , Valleroy Linda , Chen Sanny , Catania Joseph 
Published: April 2007

Objectives. We sought to determine the prevalence of HIV and novel cofactors of high-transmission-risk behavior in a probability sample of men who have sex with men (MSM). Methods. We performed a cross-sectional telephone survey of 1976 adult MSM in San Francisco. Results. We found an HIV prevalence of 25.2%. Predictors of unprotected insertive anal intercourse with a serodiscordant (not having the same HIV/AIDS serostatus) partner among HIV-infected men included use of Viagra and a greater number of partners in the past 12 months. Unprotected receptive anal intercourse with a serodiscordant partner among men not known to be HIV infected was independently associated with having lived in San Francisco for less than 1 year, use of crystal methamphetamine and amyl nitrites, a greater number of partners, and agreement with the statement, “You are less careful about being safe with sex or drugs than you were several years ago because there are better treatments for HIV now.” Conclusions. Strategies to prevent HIV for urban MSM should focus on new predictors of HIV transmission.
Ethics in Public Health Research
Authors: Graham Wendy J. , Hussein Julia 
Published: April 2007

Maternal and perinatal mortality reduction has remained a priority on the international health agenda for nearly 2 decades. During this time, strategies for achieving these goals have shifted in emphasis from prevention of pregnancies to provision of care. Robust evidence is limited, particularly regarding what works best in delivering care in specific health system settings and at the population level. We describe the limited evidence base using a framework that highlights the consequences of the major gaps in measurement, evidence, and action, and we discuss existing opportunities for bridging these gaps at the policy level. Capitalizing on current global policy interests and generating demand-driven evidence is a priority for enabling documentation of progress toward reaching the United Nations Millennium Development Goals for 2015.
Growth Trajectories of Sexual Risk Behavior in Adolescence and Young Adulthood
Authors: Fergus Stevenson , Zimmerman Marc A. , Caldwell Cleopatra H. 
Published: April 2007

Objectives. Adolescence and young adulthood (ages 18–25 years) are periods of development and change, which include experimentation with and adoption of new roles and behaviors. We investigated longitudinal trajectories of sexual risk behaviors across these time periods and how these trajectories may be different for varying demographic groups.Methods. We developed multilevel growth models of sexual risk behavior for a predominantly African American sample (n=847) that was followed for 8 years, from adolescence to young adulthood. We investigated differences in growth parameters by race/ethnicity and gender and their interactions.Results. The final model included linear and quadratic terms for both adolescence and young adulthood, indicating acceleration of sexual risk behaviors during adolescence and a peak and deceleration during young adulthood. African American males exhibited the highest rate of sexual risk behavior in ninth grade, yet had the slowest rate of growth. Compared with their White peers, African American males and females exhibited less sexual risk behavior during young adulthood.Conclusions. Our results suggest that youths of different races/ethnicities and genders exhibit varying sexual risk behavior trajectories.
Directly Observed Highly Active Antiretroviral Therapy for HIV-Infected Children in Cambodia
Authors: Myung Patricia , Pugatch David , Brady Mark F. , Many Phok , Harwell Joseph I. , Lurie Mark , Tucker John 
Published: April 2007

Antiretroviral medications are becoming available for HIV-infected children in resource-limited settings. Maryknoll, an international Catholic charity, provided directly observed antiretroviral therapy to HIV-infected children in Phnom Penh, Cambodia. Child care workers administered generic antiretroviral drugs twice daily to children, ensuring adherence. Treatment began with 117 late-stage HIV-infected children; 22 died of AIDS during the first 6 months. The rest were treated for at least 6 months and showed CD4 count increases comparable to those achieved in US and European children. Staffing cost for this program was approximately US $5 per child per month, or 15% more than the price of the medications. Drug toxicities were uncommon and easily managed. Directly observed antiretroviral therapy appears to be a promising, low-cost strategy for ensuring adherent treatment for HIV-infected children in a resource-limited setting.
Pro12Ala Polymorphism of the PPARγ2 Locus Modulates the Relationship Between Energy Intake and Body Weight in Type 2 Diabetic Patients
Authors: Vaccaro Olga , Lapice Emanuela , Monticelli Antonella , Giacchetti Manuela , Castaldo Imma , Galasso Rocco , Pinelli Michele , Donnarumma Giovanna , Rivellese Angela A. , Cocozza Sergio , Riccardi Gabriele 
Published: April 2007

OBJECTIVE—We explore the relationship among BMI, habitual diet, and the Pro12Ala polymorphism in the peroxisome proliferator–activated receptor (PPAR)γ2.
RESEARCH DESIGN AND METHODS—The Pro12Ala variant was characterized in 343 unrelated type 2 diabetic patients who were consecutively seen at the outpatient clinic of a health district of the province of Naples. Anthropometric and laboratory parameters were measured; habitual diet was assessed by a validated semiquantitative food frequency questionnaire.
RESULTS—The overall frequency of Ala12 was 12% (n = 42). BMI was significantly higher in Ala carriers than non-Ala carriers, whereas total daily energy intake or macronutrient composition of the diet were similar in the two groups. For further analysis, participants were stratified according to genotype and sex-specific quartiles of energy intake. BMI increased in both genotype groups with increasing energy intake (P &lt; 0.03). BMI was similar in Ala carriers and non-Ala carriers (30.0 vs. 30.1 kg/m2, P &gt; 0.10) in the lower quartile of energy intake but significantly higher in Ala carriers in the upper quartile (36.0 vs. 32.1 kg/m2, P &lt; 0.001). Average daily energy intake and diet composition were comparable within each quartile for carriers or noncarriers of the Ala allele. Relative to the noncarriers, Ala carriers had a significantly lower energy intake per kilogram body weight, thus suggesting that the Ala allele is associated with a higher food efficiency. The confounding role of medications, glucose control, and physical exercise was ruled out.
CONCLUSIONS—This study provides evidence of a differential susceptibility to fat accumulation, and, hence, weight gain, in response to habitual high energy intake for Ala carriers compared with Pro/Pro homozygotes.
Kidney Function After Islet Transplant Alone in Type 1 Diabetes
Authors: Maffi Paola , Bertuzzi Federico , De Taddeo Francesca , Magistretti Paola , Nano Rita , Fiorina Paolo , Caumo Andrea , Pozzi Paolo , Socci Carlo , Venturini Massimo , del Maschio Alessandro , Secchi Antonio 
Published: April 2007

OBJECTIVE—Islet transplantation alone is an alternative for the replacement of pancreatic endocrine function in patients with type 1 diabetes. The aim of our study was to assess the impact of the Edmonton immunosuppressive protocol (tacrolimus-sirolimus association) on kidney function.
RESEARCH DESIGN AND METHODS—Nineteen patients with type 1 diabetes and metabolic instability received islet transplantation alone and immunosuppressive therapy according to the Edmonton protocol. Serum creatinine (sCr), creatinine clearance (CrCl), and 24-h urinary protein excretion (UPE) were assessed at baseline and during a follow-up of 339 patient-months.
RESULTS— After islet transplantation we observed 1) sCr within the normal range in all but two patients in whom sCr increased immediately after islet transplantation, and despite withdrawal of immunosuppression, patients progressed to end-stage renal disease (ESRD); 2) CrCl remained within the normal range for those patients who had normal baseline values and decreased, progressing to ESRD in two patients with a decreased baseline CrCl; and 3) 24-h UPE worsened (&gt;300 mg/24 h) in four patients. In the two patients who progressed to ESRD, the worsening of 24-h UPE occurred immediately after islet transplantation. In one patient 24-h UPE worsening occurred at 18 months, and, after withdrawal of immunosuppression, it returned to the normal range. In another patient 24-h UPE increased at 24 months and remained stable while immunosuppression was continued.
CONCLUSIONS—In type 1 diabetic patients receiving islet transplantation alone, the association of tacrolimus and sirolimus should be used only in patients with normal kidney function. Alternative options for immunosuppressive treatment should be considered for patients with even a mild decrease of kidney function.
Whole-Body Glycolysis Measured by the Deuterated-Glucose Disposal Test Correlates Highly With Insulin Resistance In Vivo
Authors: Beysen Carine , Murphy Elizabeth J. , McLaughlin Tracey , Riiff Timothy , Lamendola Cindy , Turner Holly C. , Awada Mohamad , Turner Scott M. , Reaven Gerald , Hellerstein Marc K. 
Published: April 2007

OBJECTIVE—The purpose of this study was to compare an in vivo test of whole-body glycolysis, the deuterated-glucose disposal test (2H-GDT), with insulin sensitivity measured by the euglycemic-hyperinsulinemic glucose clamp and the steady-state plasma glucose (SSPG) test.
RESEARCH DESIGN AND METHODS—The 2H-GDT consists of an oral glucose challenge containing deuterated glucose, followed by measurement of heavy water (2H2O) production, which represents whole-body glycolytic disposal of the glucose load. 2H2O production is corrected for ambient insulin concentration as an index of tissue insulin sensitivity. The 2H-GDT was compared with euglycemic-hyperinsulinemic glucose clamps in healthy lean subjects (n = 8) and subjects with the metabolic syndrome (n = 9) and with the SSPG test in overweight (n = 12) and obese (n = 6) subjects.
RESULTS—A strong correlation with the clamp was observed for the 75-g and 30-g 2H-GDT (r = 0.95, P &lt; 0.0001 and r = 0.88, P &lt; 0.0001, respectively). The 2H-GDT and clamp studies revealed marked insulin resistance in subjects with metabolic syndrome compared with lean control subjects. The correlation with the clamp was maintained in each group (lean, r = 0.86, P &lt; 0.01; metabolic syndrome, r = 0.81, P &lt; 0.01) for the 75-g test. The 2H-GDT also correlated strongly with the SSPG test (r = −0.87, P &lt; 0.0001) in overweight and obese subjects.
CONCLUSIONS—The 2H-GDT, which measures whole-body glycolysis in humans in a quantitative manner, correlates highly with the euglycemic-hyperinsulinemic glucose clamp and the SSPG test. Impaired insulin-mediated whole-body glycolysis is a feature of insulin resistance, which provides a means of assessing insulin sensitivity in vivo.
Glucose Homeostasis and Genotype-Phenotype Interplay in Cystic Fibrosis Patients With CFTR Gene ΔF508 Mutation
Authors: Preumont Vanessa , Hermans Michel P. , Lebecque Patrick , Buysschaert Martin 
Published: April 2007

OBJECTIVE—We sought to determine the clinical phenotype of adolescent/adult patients with cystic fibrosis, according to heterozygosity or homozygosity for cystic fibrosis transmembrane regulator (CFTR) ΔF508 mutation, and to analyze their characteristics according to glucose tolerance status.
RESEARCH DESIGN AND METHODS—A total of 76 cystic fibrosis patients with CFTR ΔF508 mutation (33 heterozygous and 43 homozygous) stratified according to normal glucose tolerance (NGT) (n = 51) or abnormal glucose homeostasis (AGH) (impaired fasting glucose, impaired glucose tolerance, or diabetes; n = 25) had their homeostasis model assessment (HOMA) of β-cell function and of insulin sensitivity and hyperbolic product (β-cell function × insulin sensitivity [B × S]) measured. Pancreatic exocrine insufficiency was inferred from pancreatine requirements. Clinical effects of insulin therapy on weight and lung function were recorded.
RESULTS—AGH was observed in 24 and 40% of heterozygous and homozygous subjects, respectively. AGH patients were older than NGT patients (mean ± SD age 29 ± 10 vs. 23 ± 8 years, P = 0.006), and their β-cell function was lower (93 ± 49 vs. 125 ± 51%, P = 0.011). Insulin sensitivity values were comparable in NGT and AGH patients. A lower B × S product was observed in AGH, although it was nonsignificant when adjusted for error propagation. Pancreatic insufficiency was observed in 52 and 100% of heterozygous and homozygous patients (P = 0.001).
CONCLUSIONS—Pre-diabetes and diabetes represent frequent comorbidities in CFTR ΔF508 mutation in the homozygous or heterozygous states. Impairment of insulin secretion, as shown by HOMA, is an important determinant when compared with the magnitude of compensation from insulin sensitivity. Given the high prevalence of abnormal glucose tolerance, screening for (pre-)diabetes is mandatory. Insulin supplementation in diabetic subjects with CFTR ΔF508 mutation seems a rational therapy for consideration, although this does not preclude that therapy directed toward insulin resistance could also interact.