TrueNTH sexual recovery study protocol: a multi-institutional collaborative approach to developing and testing a web-based intervention for couples coping with the side-effects of prostate cancer treatment in a randomized controlled trial.

BACKGROUND: Over half of men who receive treatment for prostate suffer from a range of sexual problems that affect negatively their sexual health, sexual intimacy with their partners and their quality of life. In clinical practice, however, care for the sexual side effects of treatment is often suboptimal or unavailable. The goal of the current study is to test a web-based intervention to support the recovery of sexual intimacy of prostate cancer survivors and their partners after treatment. METHODS: The study team developed an interactive, web-based intervention, tailored to type of treatment received, relationship status (partnered/non-partnered) and sexual orientation. It consists of 10 modules, six follow the trajectory of the illness and four are theme based. They address sexual side effects, rehabilitation, psychological impacts and coaching for self-efficacy. Each includes a video to engage participants, psychoeducation and activities completed by participants on the web. Tailored strategies for identified concerns are sent by email after each module. Six of these modules will be tested in a randomized controlled trial and compared to usual care. Men with localized prostate cancer with partners will be recruited from five academic medical centers. These couples (N = 140) will be assessed prior to treatment, then 3 months and 6 months after treatment. The primary outcome will be the survivors' and partners' Global Satisfaction with Sex Life, assessed by a Patient Reported Outcome Measure Information Systems (PROMIS) measure. Secondary outcomes will include interest in sex, sexual activity, use of sexual aids, dyadic coping, knowledge about sexual recovery, grief about the loss of sexual function, and quality of life. The impact of the intervention on the couple will be assessed using the Actor-Partner Interaction Model, a mixed-effects linear regression model able to estimate both the association of partner characteristics with partner and patient outcomes and the association of patient characteristics with both outcomes. DISCUSSION: The web-based tool represents a novel approach to addressing the sexual health needs of prostate cancer survivors and their partners that-if found efficacious-will improve access to much needed specialty care in prostate cancer survivorship. TRIAL REGISTRATION: Clinicaltrials.gov registration # NCT02702453 , registered on March 3, 2016.

Using doubly labeled water to validate associations between sugar-sweetened beverage intake and body mass among White and African-American adults.

BACKGROUND: Evidence is mixed regarding sugar-sweetened beverage (SSB) intake and adiposity among adults, perhaps because of reporting bias. OBJECTIVE: The objective of this study is to determine the impact of reporting bias on any associations between increased SSB intake and overweight/obesity. DESIGN: Beverage intake and overweight/obese status (body mass index ≥ 25 kg m(-2)) were examined among adults from a dietary assessment and doubly labeled water study (n=250). Four web-based, 24-h recalls assessed dietary intake. SSB intake was categorized as no intake, 1-99 kcals per day and >99 kcals per day. Logistic regression models adjusted for total caloric intake, age, race, education and diet quality compared SSB intake with overweight/obese status. To investigate dietary self-reporting bias, analyses were replicated in a subset of 'true reporters': those with self-reported total caloric intake within 25% of total energy expenditure per doubly labeled water assessments (n=108). RESULTS: One-half of participants were overweight/obese; more overweight/obese participants consumed SSB than normal-weight participants (69% vs 47%; P<0.001). Intake of other beverages did not differ by adiposity. Less number of White participants (48%) consumed SSB compared with African-American participants (68%; P=0.002). Compared with no intake, SSB intake up to the median intake doubled the risk of being overweight/obese (odds ratio: 2.1, 95% confidence interval: 1.0-4.3; P=0.046) and SSB intake over the median more than doubled the risk (odds ratio: 2.6, 95% confidence interval: 1.2-6.0; P=0.018). When limited to true reporters, SSB intake significantly increased the risk of being overweight/obese by nearly fourfold. CONCLUSION: Underreporting of SSB intake may be attenuating true associations of SSB intake and the risk of being overweight/obese.

Timing of energy intake during the day is associated with the risk of obesity in adults.

BACKGROUND: The timing of energy intake is a modifiable behaviour that may influence energy regulation and the risk of obesity. We examined the associations of energy intake in the morning, midday and evening with body mass index (BMI) (n = 239). METHODS: Cross-sectional analyses were performed using data from the University of California, Los Angeles Energetics Study. Energy intake was assessed using three 24-h dietary recalls and stratified by time-of-day: morning (00.00 h to 11.00 h), midday (11.00 h to 17.00 h) and evening (17.00 h to 00.00 h). Sensitivity analysis was conducted among 'true-reporters', whose self-reported energy intake was ±25% of total energy expenditure measured by doubly-labelled water (n = 99). Logistic regression models were performed adjusting for age, sex, race, education, total daily energy intake and physical activity. RESULTS: Energy intake in the morning was not associated with BMI. Participants who consumed ≥33% (versus <33%) of their daily energy intake at 12.00 h were (nonsignificantly) less likely to be overweight/obese [odds ratio (OR) = 0.68; 95% confidence interval (CI) = 0.37-1.24] and this association was stronger and statistically significant among true-reporters (OR = 0.34; 95% CI = 0.12-0.95). Those who consumed ≥33% of daily energy intake in the evening were two-fold more likely overweight/obese (OR = 2.00; 95% CI = 1.03-3.89), although this association was not significant among true-reporters (OR = 2.10; 95% CI = 0.60-7.29). CONCLUSIONS: These data indicate that eating more of the day's total energy intake at midday is associated with a lower risk of being overweight/obese, whereas consuming more in the evening is associated with a higher risk. Randomised trials are needed to test whether shifting energy intake earlier in the day could have a regulatory effect with respect to reducing intake in the evening, thereby promoting weight loss and maintenance.

Leber's idiopathic stellate neuroretinitis: A clinical case.

Introduction: In 1916, Leber's idiopathic stellate neuroretinitis (LISN) was described by Theodore Leber as a rare disease characterized by optic disc swelling associated with a macular star. This fundus appearance can have multiple causes but the etiology of Leber's idiopathic stellate neuroretinitis remains unknown. Case report: A 40 year-old man consulted for a progressive decline in visual acuity and a blurred vision in his left eye. Corrected Visual acuity of the left eye was hand motion, Funduscopy of the left eye revealed a stellate maculopathy with loss of foveolar depression and a normal optic disc. The angiography confirmed an optic disc oedema. Laboratory investigations were normal. No infectious nor inflammatory etiology was found. Brain imaging was normal. Patient received 3 days of intravenous methylprednisolone at 10mg/kg/D for 3 days in a row and an oral relay was started with a progressive degression over 2 weeks. The evolution after treatment was satisfactory, the visual acuity 3 weeks after the intravenous injection of corticoids increased to 2/10. Discussion: Leber's idiopathic stellate neuroretinitis (LISN) is a disorder characterized by disc oedema, peripapillary and macular hard exudates and, often, the presence of vitreous cells. The changes in the optic nerve are the primary cause of reduced vision in this condition. The more common treatable causes must be excluded wich are cat scratch disease (CSD) and vascular disease. 50% of cases have no identifiable cause and are labeled idiopathic neuroretinitis. There is no consensus regarding optimal treatment. The prognosis of Leber's idiopathic stellate neuroretinitis is good in most cases. Conclusion: The cause of neuroretinitis must be aggressively pursued before a diagnosis of lebre's idiopathic neuroretinis can be retained in order to formulate an appropriate treatment strategy.

Chronic ozone exposure preferentially modifies root rather than foliar metabolism of date palm (Phoenix dactylifera) saplings.

In their natural environment, date palms are exposed to chronic atmospheric ozone (O3) concentrations from local and remote sources. In order to elucidate the consequences of this exposure, date palm saplings were treated with ambient, 1.5 and 2.0 times ambient O3 for three months in a free-air controlled exposure facility. Chronic O3 exposure reduced carbohydrate contents in leaves and roots, but this effect was much stronger in roots. Still, sucrose contents of both organs were maintained at elevated O3, though at different steady states. Reduced availability of carbohydrate for the Tricarboxylic acid cycle (TCA cycle) may be responsible for the observed reduced foliar contents of several amino acids, whereas malic acid accumulation in the roots indicates a reduced use of TCA cycle intermediates. Carbohydrate deficiency in roots, but not in leaves caused oxidative stress upon chronic O3 exposure, as indicated by enhanced malonedialdehyde, H2O2 and oxidized glutathione contents despite elevated glutathione reductase activity. Reduced levels of phenolics and flavonoids in the roots resulted from decreased production and, therefore, do not indicate oxidative stress compensation by secondary compounds. These results show that roots of date palms are highly susceptible to chronic O3 exposure as a consequence of carbohydrate deficiency.

Saturated fat intake and prostate cancer aggressiveness: results from the population-based North Carolina-Louisiana Prostate Cancer Project.

BACKGROUND: Epidemiologic and laboratory evidence supports a role for cholesterol in prostate cancer (PC). Dietary saturated fat content impacts serum cholesterol levels. However, epidemiologic associations between saturated fat and PC aggressiveness are inconsistent. We hypothesized that high saturated fat intake would be associated with increased PC aggressiveness, and that statin use would modify this association. METHODS: Of 1854 PC cases in the North Carolina-Louisiana PC Project, 321 (17%) were classified as high aggressive (Gleason sum ⩾8, PSA>20 ng ml-1, or Gleason sum ⩾7 and clinical stage T3-4) or low/intermediate aggressive (all other cases). Using low/intermediate aggressive cases as the referent group, we examined the association between tertiles of total fat-adjusted saturated fat intake and high aggressive PC using logistic regression, overall and stratified by race and statin use. We examined total fat-adjusted polyunsaturated and monounsaturated fatty acids (PUFA and MUFA, respectively), trans fat and cholesterol intake in secondary analysis. RESULTS: High total fat-adjusted saturated fat intake was associated with an elevated odds ratio (OR) for aggressive PC (ORT3vsT1 1.51; 95% CI 1.10-2.06; P-trend=0.009), with an attenuated association in statin users (ORT3vsT1 1.16; 95% CI 0.67-2.01; P-trend=0.661) compared with non-users (ORT3vsT1 1.71; 95% CI 1.16-2.51; P-trend=0.053). High total fat-adjusted cholesterol intake was associated with aggressive PC in European Americans (ORT3vsT1 1.62; 95% CI 1.02-2.58; P-trend=0.056), but not African Americans (ORT3vsT1 0.92; 95% CI 0.60-1.42; P-trend=0.750). High total fat-adjusted PUFA was inversely associated with PC aggressiveness (ORT3vsT1 0.75; 95% CI 0.55-1.03), although this was not significant. No associations were found between total fat-adjusted MUFA or trans fat and PC aggressiveness. CONCLUSIONS: High total fat-adjusted saturated fat intake was associated with increased PC aggressiveness, with a suggestion of a stronger effect in men not using statins. The association between total fat-adjusted cholesterol intake and PC aggressiveness was most pronounced in European Americans.

A cross sectional study of the association between walnut consumption and cognitive function among adult US populations represented in NHANES.

OBJECTIVE: To examine the association between walnut consumption and measures of cognitive function in the US population. DESIGN: Nationally representative cross sectional study using 24 hour dietary recalls of intakes to assess walnut and other nut consumption as compared to the group reporting no nut consumption. SETTING: 1988-1994 and 1999-2002 rounds of the National Health and Nutrition Examination Survey (NHANES). POPULATION: Representative weighted sample of US adults 20 to 90 years of age. MAIN OUTCOME MEASURE: The Neurobehavioral Evaluation System 2 (NES2), consisting of simple reaction time (SRTT), symbol digit substitution (SDST), the single digit learning (SDLT), Story Recall (SRT) and digit-symbol substitution (DSST) tests. RESULTS: Adults 20-59 years old reporting walnut consumption of an average of 10.3 g/d required 16.4ms less time to respond on the SRTT, P=0.03, and 0.39s less for the SDST, P=0.01. SDLT scores were also significantly lower by 2.38s (P=0.05). Similar results were obtained when tertiles of walnut consumption were examined in trend analyses. Significantly better outcomes were noted in all cognitive test scores among those with higher walnut consumption (P < 0.01). Among adults 60 years and older, walnut consumers averaged 13.1 g/d, scored 7.1 percentile points higher, P=0.03 on the SRT and 7.3 percentile points higher on the DSST, P=0.05. Here also trend analyses indicate significant improvements in all cognitive test scores (P < 0.01) except for SRTT (P = 0.06) in the fully adjusted models. CONCLUSION: These significant, positive associations between walnut consumption and cognitive functions among all adults, regardless of age, gender or ethnicity suggest that daily walnut intake may be a simple beneficial dietary behavior.

Lycopene and cardiovascular disease.

Considerable evidence suggests that lycopene, a carotenoid without provitamin A activity found in high concentrations in a small set of plant foods, has significant antioxidant potential in vitro and may play a role in preventing prostate cancer and cardiovascular disease in humans. Tomato products, including ketchup, tomato juice, and pizza sauce, are the richest sources of lycopene in the US diet, accounting for >80% of the total lycopene intake of Americans. Unlike other carotenoids, lycopene is not consistently lower among smokers than among nonsmokers, suggesting that any possible preventive activity is not as an antioxidant. Instead, lycopene may have a cholesterol synthesis-inhibiting effect and may enhance LDL degradation. Available evidence suggests that intimal wall thickness and risk of myocardial infarction are reduced in persons with higher adipose tissue concentrations of lycopene. The question of whether lycopene helps to prevent cardiovascular disease can only be answered by a trial specifically evaluating its effectiveness in this area.

Garlic consumption and cancer prevention: meta-analyses of colorectal and stomach cancers.

BACKGROUND: Animal and in vitro studies have provided evidence of an anticarcinogenic effect of active ingredients in garlic. OBJECTIVE: The objective was to conduct meta-analyses of the epidemiologic literature on the association between garlic consumption and risk of stomach, colon, head and neck, lung, breast, and prostate cancers. DESIGN: Meta-analyses were conducted for all cancers mutually and separately for colorectal and stomach cancers in relation to consumption of exclusively raw garlic, cooked garlic, or both (RC garlic). Eighteen studies reported a relative risk estimate for RC garlic consumption and cancer risk. RESULTS: In the meta-analyses of colorectal and stomach cancer, the reference categories ranged from no consumption to consumption of 3.5 g/wk, whereas the highest categories ranged from any consumption to >28.8 g/wk. The average difference between the highest and lowest categories was 16 g/wk. The random-effects relative risk (RR) estimate of colorectal cancer and RC garlic consumption, excluding garlic supplements, was 0.69 (95% CI: 0.55, 0.89). For stomach cancer, the random-effects RR estimate was 0.53 (95% CI: 0.31, 0.92). The heterogeneity among studies for the latter outcome (P: = 0.0002) indicates the questionableness of the generalizability of this summary estimate. An indication of publication bias for all cancers combined is evident from a funnel plot of RC garlic consumption and cancer risk and from the results of the Begg and Mazumdar test (P: = 0.049). CONCLUSIONS: High intake of RC garlic may be associated with a protective effect against stomach and colorectal cancers. Heterogeneity of effect estimates, differences in dose estimation, publication bias, and possible alternative hypotheses (eg, confounding by total vegetable consumption) preclude sole reliance on summary effect estimates.

Salt and hypertension: data from the "Heidelberg Study".

Prevalence of hypertension and "intake" of sodium chloride (as estimated from 24-hr urinary Na-excretion) were measured in a random sample (n = 800) of 20- to 40-year-old Heidelberg men. There was a high (14%) prevalence of hypertension and a high (mean = 11.32 g) NcCl intake; both showed, however, no correlation. The lack of a NaCl/blood pressure correlation in this cross-sectional study might be due to intra- and interindividual variability of both parameters and, possibly, to a "threshold" argument concerning the etiological role of sodium in hypertension.

Influence of diet on high-density lipoproteins.

Evidence of a relation between diet and high-density lipoprotein (HDL) levels in humans comes from numerous cross-sectional and experimental studies. Evaluation of data from cross-sectional nutrition and health surveys sometimes yields different results for men and women but usually demonstrates positive correlations of HDL cholesterol levels with total energy intake, alcohol consumption, dietary cholesterol and total and animal fat, and negative correlations of HDL with dietary carbohydrates (simple sugars) and, in some instances, plant fats. Short-term dietary manipulation produced confirmatory evidence of a causal relation between diet and HDL with regard to several of these factors; however, there are few long-term data. The underlying mechanisms as well as the relation of HDL manipulation to cardiovascular health are still to be defined, particularly because the functions and fates of the HDL molecule may vary according to its composition and turnover, which are not reflected by the HDL cholesterol concentration. Furthermore, some relations between diet and HDL may only be the result of other metabolic consequences of dietary change, for instance, triglyceride metabolism and other lipoproteins. Although there is consistent evidence that a high HDL cholesterol level is indicative of a low risk of coronary heart disease in industrialized populations, evidence is inconclusive that manipulation of HDL leads to an alteration of risk.

Nutritional status of folate and colon cancer risk: evidence from NHANES I epidemiologic follow-up study.

PURPOSE: This manuscript utilized the NHANES I Epidemiologic Follow-up Study (NHEFS), a national probability sample of the U.S. non-institutionalized population, to examine whether the intake of folate at baseline is associated with colon cancer risk. METHODS: The NHEFS consists of 14,407 subjects with 20 years of follow-up. Sociodemographic status, dietary information, family history of colon cancer, alcohol and aspirin use, smoking status, and body mass index (BMI) are included in the Cox proportional hazard model to examine confounding effects. RESULTS: After adjusting for confounders, a marginally significant association was observed between folate intake and reduced colon cancer risk. Gender and alcohol consumption appears to have an interactive effect with this association. The stratified results suggest that dietary folate is significantly inversely associated with colon cancer in men (relative risk (RR) = 0.40, 95% confidence interval (CI) = 0.18, 0.88) who consumed more than 249 microg/day of folate and that there is a significant dose-response relationship (p = 0.03). The association did not reach statistical significance in women. Using a composite dietary profile, we found that there is a significantly increased risk for men who consumed low-folate, low-methionine, and high alcohol diets when compared to male non-drinkers who consumed high-folate and high methionine diets (RR = 2.67, 95% CI = 1.16, 6.16). CONCLUSIONS: This study found significant association between folate intake and reduced colon cancer risk among men and non-drinkers, but not women or drinkers. The study supports a synergistic interaction between intakes of folate, methionine and alcohol and colon cancer risk.

Plasma and lung macrophage responsiveness to carotenoid supplementation and ozone exposure in humans.

OBJECTIVE: To examine the effect of ozone exposure and vegetable juice supplementation on plasma and lung macrophage concentrations of carotenoids. DESIGN: A randomized trial. SETTING: Subjects were exposed to ambient air prior to antioxidant supplementation and to ozone after antioxidant supplementation or placebo. Exposures occurred while exercising intermittently in a controlled metabolic chamber at the Human Studies Division, US EPA. SUBJECTS: In all, 23 healthy subjects between ages of 18 and 35 y. INTERVENTIONS: Subjects consumed a low fruit and vegetable diet for 3 weeks. After the first week, subjects underwent a sham exposure to filtered air with exercise, followed by bronchoalveolar lavage (BAL). Subjects were randomly assigned into supplement (one can vegetable juice, vitamins C and E daily) or placebo (orange soda, placebo pill daily) groups for 2 weeks. After the 2-week intervention, subjects were exposed to 0.4 ppm (784 microg/m(3)) ozone for 2 h with exercise followed by BAL. Blood samples were drawn before, immediately after and 3 h postexposure on each exposure day. The concentrations of nine carotenoids were determined by HPLC in BAL macrophages and plasma samples. RESULTS: Plasma concentrations of all the carotenoids that were present in the vegetable juice (except cis-beta-carotene) increased significantly in the supplemented group. Lung macrophage alpha-carotene concentrations increased significantly, lycopene isomers increased slightly, and all other carotenoids decreased (nonsignificantly) in the supplementation group following the intervention. Ozone exposure resulted in decreases in several carotenoids in plasma of the placebo group, but not in the supplemented group. CONCLUSIONS: Lung macrophage concentrations of carotenoids can be manipulated by diet. Ozone is a potent environmental oxidant that appears to reduce plasma carotenoids in nonsupplemented individuals.

Dietary intake associated with serum versus urinary carboxymethyl-lysine, a major advanced glycation end product, in adults: the Energetics Study.

BACKGROUND/OBJECTIVES: Advanced glycation end products (AGEs) are implicated in the pathogenesis of atherosclerosis, diabetes and kidney disease. The objective was to describe dietary intake, the dominant source of exposure to AGEs, with carboxymethyl-lysine (CML), a major AGE, in serum and urine, respectively. SUBJECTS/METHODS: Serum and urinary CML were measured in 261 adults, aged 21-69 years, and compared with diet as assessed by six separate 24-h dietary recalls. RESULTS: Median (25th, 75th percentile) serum and urinary CML concentrations were 686 (598, 803) µg/l and 1023 (812, 1238) µg/gm creatinine. There was no correlation between serum and urinary CML (r=-0.02, P=0.78). Serum CML was positively correlated with intake of soy, fruit juice, cold breakfast cereal, non-fat milk, whole grains, fruit, non-starchy vegetables and legumes, and negatively correlated with intake of red meat. Intake of fast food was not significantly correlated with serum CML. Urinary CML was positively correlated with intake of starchy vegetables, whole grains, sweets, nuts/seeds and chicken, and negatively correlated with intake of fast foods. Intake of AGE-rich foods such as fried chicken, French fries, bacon/sausage and crispy snacks were not significantly correlated with serum or urinary CML, except for a significant negative correlation between fried chicken and serum CML. CONCLUSIONS: These findings suggest that the high consumption of foods considered high in CML is not a major determinant of either serum or urinary CML. Further work is needed to understand the relationship of AGEs in blood and urine with the metabolism of dietary AGEs.

Feasibility testing of an automated image-capture method to aid dietary recall.

BACKGROUND/OBJECTIVES: The accuracy of dietary recalls might be enhanced by providing participants with photo images of foods they consumed during the test period. SUBJECTS/METHODS: We examined the feasibility of a system (Image-Diet Day) that is a user-initiated camera-equipped mobile phone that is programmed to automatically capture and transmit images to a secure website in conjunction with computer-assisted, multipass, 24-h dietary recalls in 14 participants during 2007. Participants used the device during eating periods on each of the three independent days. Image processing filters successfully eliminated underexposed, overexposed and blurry images. The captured images were accessed by the participants using the ImageViewer software while completing the 24-h dietary recall on the following day. RESULTS: None of the participants reported difficulty using the ImageViewer. Images were deemed 'helpful' or 'sort of helpful' by 93% of participants. A majority (79%) of users reported having no technical problems, but 71% rated the burden of wearing the device as somewhat to very difficult, owing to issues such as limited battery life, self-consciousness about wearing the device in public and concerns about the field of view of the camera. CONCLUSION: Overall, these findings suggest that automated imaging is a promising technology to facilitate dietary recall. The challenge of managing the thousands of images generated can be met. Smaller devices with a broader field of view may aid in overcoming self-consciousness of the user with using or wearing the device.

Consequences of Aberrant Insulin Regulation in the Brain: Can Treating Diabetes be Effective for Alzheimer's Disease.

There is an urgent need for new ways to treat Alzheimer's disease (AD), the most common cause of dementia in the elderly. Current therapies are modestly effective at treating the symptoms, and do not significantly alter the course of the disease. Over the years, a range of epidemiological and experimental studies have demonstrated interactions between diabetes mellitus and AD. As both diseases are leading causes of morbidity and mortality in the elderly and are frequent co-morbid conditions, it has raised the possibility that treating diabetes might be effective in slowing AD. This is currently being attempted with drugs such as the insulin sensitizer rosiglitazone. These two diseases share many clinical and biochemical features, such as elevated oxidative stress, vascular dysfunction, amyloidogenesis and impaired glucose metabolism suggesting common pathogenic mechanisms. The main thrust of this review will be to explore the evidence from a pathological point of view to determine whether diabetes can cause or exacerbate AD. This was supported by a number of animal models of AD that have been shown to have enhanced pathology when diabetic conditions were induced. The one drawback in linking diabetes and insulin to AD has been the postmortem studies of diabetic brains demonstrating that AD pathology was not increased; in fact decreased pathology has often been reported. In addition, diabetes induces its own distinct features of neuropathology different from AD. There are common pathological features to be considered including vascular abnormalities, a major feature arising from diabetes; there is increasing evidence that vascular abnormalities can contribute to AD. The most important common mechanism between insulin-resistant (type II) diabetes and AD could be impaired insulin signaling; a form of toxic amyloid can damage neuronal insulin receptors and affect insulin signaling and cell survival. It has even been suggested that AD could be considered as "type 3 diabetes" since insulin can be produced in brain. Another common feature of diabetes and AD are increased advanced glycation endproduct-modified proteins are found in diabetes and in the AD brain; the receptor for advanced glycation endproducts plays a prominent role in both diseases. In addition, a major role for insulin degrading enzyme in the degradation of Aß peptide has been identified. Although clinical trials of certain types of diabetic medications for treatment of AD have been conducted, further understanding the common pathological processes of diabetes and AD are needed to determine whether these diseases share common therapeutic targets.

Impacto de las redes sociales e internet en la adolescencia: aspectos positivos y negativos / Impact of social networks and internet in adolescence: strengths and weaknesses

Este artículo presenta una revisión teórica del impacto, tanto positivo como negativo, de las redes sociales en los adoles- centes y de la relación directa entre esto y el uso o abuso de las nuevas tecnologías. A su vez, se establece el vínculo entre las formas de utilizarlas y las características psicológi- cas individuales, los desarrollos previos de personalidad y el control parental. Se toma como punto de partida el desa- rrollo adolescente asociado a la construcción de la identidad juvenil en el contexto de un nuevo paradigma comunica- cional (cibercomunicación), donde el límite entre lo públi- co y lo privado se torna cada vez más difuso. Se expone la terminología propia de las redes sociales y se pone énfasis en las estrategias de supervisión y control adulto. Se deta- llan los aspectos positivos que las nuevas tecnologías ofre- cen (diversas oportunidades de aprendizaje, entretención, socialización, desarrollo de habilidades, creatividad y me- jora de la motivación al aprendizaje especialmente en ado- lescentes, entre otros) y los aspectos negativos asociados (distanciamiento afectivo, pérdida de límites en la comuni- cación y pérdida de la capacidad de escucha, entre otros). Este artículo destaca la necesidad de entregar y estimular modelos de comunicación social reales y una educación en el uso de las nuevas tecnologías. El objetivo es actualizar y orientar a profesionales de la salud sobre los aspectos posi- tivos y/o negativos de las redes sociales en los adolescentes.

This paper presents a theoretical review of the impact, both positive and negative, of social networks in adolescents and direct relationship between this and the use and abuse of new technologies, respectively. In turn, the link between forms of use to individual psychological characteristics, previous developments of personality and parental control is set. It takes as its starting point the adolescent development associated with the construction of youth identity in the context of a new communication paradigm (Cibercomunicación), where the boundary between public and private is becoming increasingly blurred. The terminology of social networks are presented and emphasis is placed on the strategies of adult supervision and control. The positive and negative aspects of new technologies are discussed (diverse learning opportunities, entertainment, socialization, skill development, creativity, improving learning motivation especially in adolescents, affective detachment, loss of detailed limits on communication, loss of the ability to listen). The need to deliver and stimulate real social models of communication and education in the use of new technologies is emphasized. The aim of this article is to update and provide a guidance to health professionals on the positive and/or negative effects of social networking on teenagers.

Incidence and risk factors for hip or other bone fractures among hemodialysis patients in the Dialysis Outcomes and Practice Patterns Study.

The available data on bone fractures in hemodialysis (HD) patients are limited to results of a few studies of subgroups of patients in the United States. This study describes the prevalence of hip fractures and the incidence and risk factors associated with hip and other fractures in representative groups of HD facilities (n=320) and patients (n=12 782) from the 12 countries in the second phase of the Dialysis Outcomes and Practice Patterns Study (2002-2004). Among prevalent patients, 2.6% had a prior hip fracture. The incidence of fractures was 8.9 per 1000 patient years for new hip fractures and 25.6 per 1000 for any new fracture. Older age (relative risk (RR)(HIP)=1.91, RR(ANY)=1.33, P<0.0001), female sex (RR(HIP)=1.41, P=0.02; RR(ANY)=1.59, P<0.0001), prior kidney transplant (RR(HIP)=2.35, P=0.04; RR(ANY)=1.76, P=0.007), and low serum albumin (RR(HIP)=1.85, RR(ANY)=1.45, per 1 g/dl lower, P<0.0001) were predictive of new fractures. Elevated risk of new hip fracture was observed for selective serotonin reuptake inhibitors and combination narcotic medications (RR=1.63, RR=1.74, respectively, P<0.05). Several medications were associated with risk of any new fracture: narcotic pain medications (RR=1.67, P=0.02), benzodiazepines (RR=1.31, P=0.03), adrenal cortical steroids (RR=1.40, P<0.05), and combination narcotic medications (RR=1.72, P=0.001). Parathyroid hormone (PTH) levels >900 pg/ml were associated with an elevated risk of any new fracture (RR=1.72, P<0.05) versus PTH 150-300. The results suggest that greater selectivity in prescribing several classes of psychoactive drugs and more efficient treatment of secondary hyperparathyroidism may help reduce the burden of fractures in HD patients.

Epidemiologic challenges in the study of the efficacy and safety of medicinal herbs.

Although clinical trials are needed to prove the efficacy of medicinal herbs and pharmacological studies are essential to the long-term goal of identifying the active ingredients in plants, these will not be forthcoming rapidly enough to meet the acute public health needs for knowledge on efficacy and safety since these substances are currently being widely consumed at various dosages. Resulting from the ongoing 'natural experiment' well-conducted observational epidemiology can bridge the gap and determine whether, as consumed its use is of benefit or detrimental, for whom and when in the course of disease prevention or minimization of disease severity. The classic study designs (cohort and case-control) and the more recent development of case-only studies can be put to service for these purposes. The challenges are in dose assessment, understanding mechanisms of effect, determining the relevant time period of exposure for a given disease or symptom, controlling for confounding factors such as disease status, and the special challenges presented by irregular use of medicinal herbs and concurrent use of multiple products and multiple sources.