The relationship between the dim light melatonin onset and sleep on a regular schedule in young healthy adults

The endogenous melatonin onset in dim light (DLMO) is a marker of circadian phase that can be used to appropriately time the administration of bright light or exogenous melatonin in order to elicit a desired phase shift. Determining an individual's circadian phase can be costly and time-consuming. We examined the relationship between the DLMO and sleep times in 16 young healthy individuals who slept at their habitual times for a week. The DLMO occurred about 2 hours before bedtime and 14 hours after wake. Wake time and midpoint of sleep were significantly associated with the DLMO (r = 0.77, r = 0.68 respectively), but bedtime was not (r = 0.36). The possibility of predicting young healthy normally entrained people's DLMOs from their sleep times is discussed.     

Genital-tract cancers in adolescents and young adults

In a review of the California Tumor Registry from 1950-1969, which records 1/3 of all cancer cases in California, there was an increase in the number of cancers of the vagina, corpus uteri, prostate, testis, and bladder (male) for the 10-19 year old age group. There was no increase in cancers of the vulva, ovary, cervix, breast, stomach, colon, rectum, and bladder (female). However, for the 20-24 year old age group, cancer of the vulva and testis increased from 1962-1969. The increases are compatible with other observations which indicate a possible association between stilbesterol and other cervical sites besides the vagina. There is a need for cancer surveillance to determine disease patterns and stimulate examination of existing data.     

Hypervolemic hyperalgesia in healthy young adults

A cardiopulmonary baroreflex mechanism may be implicated in hypertensive hypoalgesia. Previous research in animals and humans has noted that manipulations that stimulate the vagus nerve are associated with predominantly anti-nociceptive effects. This study examined the effects of cardiopulmonary baroreceptor stimulation on venipuncture and intraveneous catherization pain during euvolemic and hypervolemic conditions while participants lay supine. In the euvolemic condition, participants maintained their normal diet whereas in the hypervolemic condition, they consumed additional water containing sodium citrate. As expected, blood volume was higher (P < .05) during the hypervolemic condition than the hypovolemic condition. Pain ratings were higher (P < .05) during hypervolemia compared to euvolemia. These findings suggest that increased cardiopulmonary baroreceptor activation during hypervolemia can be associated with increased sensitivity to noxious stimulation. In agreement with previously reported pro-nociceptive effects of vagus nerve stimulation, the current hyperalgesia finding provides further evidence that the cardiovascular system can influence the pain system.     

Cognitive performance, hyperoxia, and heart rate following oxygen administration in healthy young adults

It was recently established that supplemental oxygen administration significantly enhances memory formation in healthy young adults. In the present study, a double-blind, placebo-controled design was employed to assess the cognitive and physiological effects of subjects' inspiration of oxygen or air (control) prior to undergoing simple memory and reaction-time tasks. Arterial blood oxygen saturation and heart rate were monitored during each of six phases of the experiment, corresponding to baseline, gas inhalation, word presentation, reaction time, distractor and word recall, respectively. The results confirm that oxygen administration significantly enhances cognitive performance above that seen in the air inhalation condition. Subjects who received oxygen recalled more words and had faster reaction times. Moreover, compared to participants who inhaled air, they exhibited significant hyperoxia during gas administration, word presentation, and the reaction-time task, but not at other phases of the experiment. Compared to baseline, heart rate was significantly elevated during the word presentation, reaction-time, and distractor tasks in both the air and oxygen groups. In the oxygen group, significant correlations were found between changes in oxygen saturation and cognitive performance. In the air group, greater changes in heart rate were associated with more improved cognitive performance. These results are discussed in the context of cognitive demand and metabolic supply. It is suggested that under periods of cognitive demand a number of physiological responses are brought into play that serve to increase the delivery of metabolic substrates to active neural tissue. These mechanisms can be supplemented by increased availability of circulating blood oxygen, resulting in an augmentation of cognitive performance. Heart rate reactivity and the capacity for increased blood oxygen appear to be important physiological individual differences mediating these phenomena.     

Antibody response to influenza vaccination in healthy adults

The aim of this study was to assess antibody response in 184 healthy adults vaccinated with split influenza vaccine (Begrivac, Chiron Behring). Response to hemagglutinin and neuraminidase was assessed before vaccination and after 1 month by hemagglutination inhibition test and neuraminidase inhibition test. After vaccination, statistically significant increases of antibody titers, both for hemagglutinins and for neuraminidases, were observed. The post-vaccination proportion of persons with protective antihemagglutinin antibody titers ranged from 78.4%to 90.8%, while the proportion of persons with at least a fourfold increase of antihemagglutinin antibody titers ranged from 50.5% to 71.2%. All requirements of the Committee for Proprietary Medicinal Products regarding humoral response to inactivated influenza vaccine in healthy adults were fulfilled. Due to a wide range of age of the persons included in this study, the results were also analyzed in two age groups: from 20 to 45 years and from 46 to 56 years. Nevertheless, there were no statistically significant differences in antibody response between these two groups either for hemagglutinin or for neuraminidase.     

Genital herpes and hepatitis in healthy young adults

Although case reports of herpes simplex virus (HSV) causing acute hepatitis in otherwise healthy adults have appeared recently in the literature, a prospective study of the incidence of HSV-hepatitis in the general population hitherto has not been reported. In the present study, serum samples from 124 young adults attending a sexually transmitted disease clinic with either genital herpes infections (n = 86) or non-herpes sexually transmitted diseases (n = 38) (controls) were analyzed for liver enzyme abnormalities (including aspartate aminotransferase [AST] and alanine aminotransferase [ALT]). Twelve of eighty-six (14%) herpes-infected patients had mildly abnormal liver enzyme tests (less than or equal to twice the upper limit of normal) as opposed to only 1 of 38 controls (2.6%), (P less than .05). All individuals in the herpes-hepatitis group were anicteric, and only two complained of constitutional symptoms (malaise and fatigue). Liver enzyme tests were repeated in nine herpes-hepatitis patients 1 week after their genital lesions had resolved, and in six of nine patients the results had returned to within normal limits. Four patients subsequently returned at the onset of a recurrence of their genital herpes. In all four, serum ALT levels were elevated from the previous occasion, and in three of the four levels just exceeded the upper limit of normal. One patient was followed through three recurrences of his genital herpes. In that individual, the extent of liver enzyme abnormalities appeared to correlate with the presence or absence of his genital lesions.(ABSTRACT TRUNCATED AT 250 WORDS)     

Symptoms of depression among adolescents and young adults

The authors evaluated the depressive symptomatology of 26 adolescent and 27 young adult, hospitalized patients meeting Research Diagnostic Criteria for Major Depressive Disorder. Few differences were found between these two groups with regard to either symptoms or subtypes of depression. Overall, these data indicate that Major Depressive Disorder can be easily identified in younger samples using established criteria. We also report a particularly high percentage of endogenous subtype among our patients. The RDC endogenous subtype of depression among younger inpatients may be more frequent than generally realized.     

Season of birth and personality in healthy young adults

The purpose of this study was to explore a possible season of birth effect on big five personality traits, taking into account also gender and circadian typology variables. A sample of 419 healthy young adults (249 females and 170 males) was administered the self-report version of the Big Five Observer (BFO) and the Morningness–Eveningness Questionnaire (MEQ) to determine, respectively, personality features and circadian preference. Participants were subdivided into four season groups, according to their birth date. No significant season of birth effect was observed as regards personality traits even if summer-born participants tended to score lower on the conscientiousness dimension. In regard to the conscientiousness domain, there was a significant interaction between gender and season of birth. Males presented greater conscientiousness variation with summer born participants scoring lower. On the basis of a multiple regression analysis, MEQ score proved to be a better predictor of conscientiousness than gender, age, and season of birth. The results provide no clear evidence for a season of birth effect on the big five personality traits. It is possible that circadian preference may modulate the season of birth effect on personality traits.     

Sexually transmitted disease prevention in adolescents and young adults

OBJECTIVE: Sexuality is one of the most pervasive aspects of the human life cycle. It warrants attention in childhood, adolescence and adulthood, and is an integral part of each health maintenance visit. Given this, it is unfortunate that U.S. medical schools do not offer more training in soliciting sexual histories and initiating dialogue about sexually healthy lifestyles. METHODS: Fourth-year medical student completed an adolescent and young-adult sexually transmitted disease elective. RESULTS: This elective allows medical students to confront personal biases and discomfort levels yet remain objective. It is also an opportunity to explore how the provider's body language and facial expressions can discourage information disclosure. Although sexuality is very prevalent in our society today, patients may still be apprehensive about discussing details of their sexual practices. Therefore, it becomes incumbent upon the physician to create an environment free from personal prejudice in order to best serve the patient. CONCLUSIONS: In order to promote sexual health awareness in a society that can be conservative and judgmental in this subject matter, it is essential to train all healthcare providers to lead discussions, educate patients and provide treatment in hopes that sexual health promotion will become as important as other socially accepted healthcare concerns.     

Epidemiological and immunological reasons for pertussis vaccination in adolescents and adults

The resurgence of pertussis has been the subject of considerable debate. Hypotheses to explain increased reporting in developed countries have focused mainly on three aspects: (1) increased recognition of the disease in adolescents and adults; (2) waning of vaccine-induced immunity and (3) loss of vaccine efficacy due to an antigenic shift of Bordetella pertussis. Waning immunity after vaccination or natural infection combined with the absence of regular boosters either in the form of vaccine boosters or natural exposure to B. pertussis – due to the low circulation of the bacterium in well-immunized populations – has been suggested to explain this shift in the age distribution of pertussis. The highest incidence of the disease is currently reported among adolescents and adults who may additionally serve as the source of infection for susceptible infants. Immunological and epidemiological data indicates the need for a universal booster vaccination against pertussis for adolescents and adults.     

Structure and cytoarchitecture of the human thymus in adolescents and young adults

The paper presents the quantitative parameters characterizing the cytoarchitecture of structural and functional components of thymus of practically healthy humans in adolescent and juvenile age periods. It was shown, that despite significant structural reorganization, in adolescence the lymphocytopoietic function of thymus was still high. In juvenile age, structural changes became more intensive. These were accompanied with the disturbances of organ function, manifested by a significant drop in mitotic index and reduction of blast cell content.     

Investigation of varicella-zoster virus DNA by the polymerase chain reaction in healthy children with varicella vaccination

Investigation of varicella-zoster virus (VZV) DNA in 20 healthy children with varicella vaccination was carried out by using the polymerase chain reaction (PCR) and nested double PCR. Samples of peripheral blood mononuclear cells (PBMC) and throat swabs were simultaneously collected 3 times (before, 1 week, and 4 weeks after vaccination) for PCR analysis. One sample of PBMC was also obtained from each of the 12 healthy children with varicella during the acute phase as a positive control. VZV DNA was not found by the first PCR in any samples except one PBMC of a control subject. The nested double PCR, which is a more sensitive method for VZV DNA detection, was applied to the same samples. The viral DNA was detected in every PBMC of the controls, and in 2 (16.7%) PBMC at 1 week and in 6 (50%) PBMC at 4 weeks after vaccination in the 12 vaccinees with seroconversion. In 3 of 4 vaccinees who were seropositive before vaccination, VZV DNA was detected in PBMC at 1 or 4 weeks after vaccination. The three vaccinees showed a booster immunization with a significant increase in antibody liters. In contrast, no VZV DNA could be detected in any throat swabs of all the vaccinees nor in PBMC of the vaccinees who did not Seroconvert. © 1994 Wiiey-Liss, Inc.     

Risky driving in adolescents and young adults with childhood ADHD

OBJECTIVE: To examine risky driving behaviors and negative driving outcomes in a large sample of adolescents and adults diagnosed in childhood with Attention Deficit Hyperactivity Disorder (ADHD) compared with demographically similar controls without ADHD. METHODS: 355 adolescents and young adults of the Pittsburgh ADHD Longitudinal Study (PALS) (n = 203 probands; n = 152 controls) were administered the Young Adult Driving Questionnaire. Parent and self-report of current ADHD symptoms and conduct problems were tested as potential mediators of the association between childhood ADHD and negative driving outcomes. RESULTS: ADHD group differences, of small to medium effect size, were found for number of tickets and accidents, and hyperactivity-impulsivity at follow-up emerged as a significant mediator of this association. Current conduct problems were associated with both risky and alcohol-impaired driving. CONCLUSIONS: Childhood ADHD elevates risk for driving-related problems, especially when symptoms persist. Co-occurring conduct problems capture some of this risk.     

Acute intravenous administration of morphine perturbs sleep architecture in healthy pain-free young adults: a preliminary study

STUDY OBJECTIVES: Pain is a leading cause of sleep disturbances in medical illness. Providing effective analgesia is considered an important intervention to reduce these sleep disturbances. Opioids remain the treatment of choice to relieve postoperative pain in hospitalized patients. However, their effects on sleep in pain patients or normal subjects remain unclear, as previous studies have been conducted mainly with former opioid addicts. The purpose of this investigation was to evaluate and describe the effects of acute clinical doses of morphine on sleep in healthy pain-free subjects. DESIGN: Subjects were randomly assigned to untreated (baseline), morphine (intravenous injections of 0.1 [corrected] mg/kg), and placebo (intravenous injections of 0.9% NaCI) conditions. SETTING: Sleep laboratory. PARTICIPANTS: Seven healthy pain-free, nonaddicts (5 women, 2 men; mean age = 25 +/- 1.6 years). MEASUREMENTS AND RESULTS: Standard polysomnographic sleep and respiratory variables were measured during 3 experimental conditions. The treatment effect was analyzed with a Latin square cross-over design followed, when appropriate, by Tukey contrasts. Morphine altered sleep architecture by reducing slow-wave sleep (non-rapid eye movement stages 3-4) and rapid eye movement sleep, and by increasing non-rapid eye movement stage 2 sleep. Results did not reveal any statistical differences for other sleep and respiratory variables. CONCLUSIONS: Similar to earlier findings in animals, nondependent opiate addicts, and postoperative patients, morphine was found to reduce duration of slow-wave sleep. Unlike previous reports, however, its acute administration produced a moderate reduction in rapid eye movement sleep and did not increase correlates of arousal (ie, awakenings, electroencephalogram arousals, wake after sleep onset). Future studies should correlate these findings in patients with pain and evaluate whether optimal pain relief with opioid therapy can improve sleep disturbances in pain patients.     

Patient-provider communication in nephrology care for adolescents and young adults

ObjectiveTo compare the relative quantity of talk between providers, caregivers, and adolescents and young adults (AYAs) with chronic kidney disease (CKD) and how communication differs by age.MethodsDuring nephrology clinic visits, conversations between AYAs with CKD (N = 99, ages 11–20, median = 15), their caregivers, and providers (N = 19) were audiotaped and coded using the Roter Interaction Analysis System. Linear mixed models tested AYA age differences in talk frequency by AYAs, caregivers, and providers. Post-hoc analyses tested differences in talk using AYA age groups.ResultsDuring clinic visits, providers spoke the most (63.7%), and caregivers spoke more (22.6%) than AYAs (13.7%). Overall talk differed by AYA age in AYAs (p < 0.001) and caregivers (p < 0.05), but not providers. Higher AYA age was associated with more AYA talk (biomedical information-giving, partnering, rapport-oriented) and less caregiver biomedical information-giving (ps < 0.001–0.05). In post-hoc analyses, young adults talked more than adolescents; caregiver talk decreased in the middle-adolescent group.ConclusionsIncreases in AYA talk occur primarily in young adulthood, whereas caregiver talk decreases in middle adolescence. This may indicate an appropriate developmental shift but raises concerns about conversational gaps during middle-adolescence.Practice implicationsDuring transition-oriented treatment planning, providers should engage both AYAs and caregivers to avoid potential gaps in communication.     

Vital capacity in trained and untrained healthy young adults in the Netherlands

Summary Slow inspiratory vital capacity was measured in 226 healthy young adults, aged from 17 to 35 years. The group included 119 men and 107 women, 87 trained subjects, 71 untrained subjects who intended to take part in a training program for competitive rowing, and 68 untrained subjects who never took part in any competitive sport.The vital capacity increased with height, weight, fat-free mass, height×fat-free mass, and height-independent fat-free mass, with men having significantly higher vital capacities than women of the same height or weight. In both males and females vital capacity showed the best relation with height×fat-free mass (correlation coefficients are 0.78 and 0.57 respectively). Multiple regression on vital capacity with height, weight, fat-free mass, height×fat-free mass, height-independent fat-free mass, percentage body fat, and age increased the correlation coefficient only slightly (0.80 and 0.59 respectively).The subjects had vital capacities that were much higher than those predicted for them by equations originating from the USA. There was no difference between the observed vital capacities and those predicted by equations originating from Europe. There is a difference in vital capacity between the European subjects studied and subjects of similar height studied in the USA. This implies that equations derived from subjects in the USA cannot be applied to European subjects.From our results we conclude that vital capacity is not increased by physical activity.We derived one simple equation that can be used to predict the vital capacity for both male and female, trained and untrained young adults, who have a similar genetic background to our subjects.     

Immunogenicity and safety of an accelerated hepatitis E vaccination schedule in healthy adults: a randomized,controlled, open-label,phase IV trial

ObjectivesThis study aimed to evaluate the immunogenicity and safety of a hepatitis E (HE) vaccine using an accelerated vaccination schedule (vaccine doses at 0, 7 and 21 days).MethodsA total of 126 participants aged ≥18 years were randomly assigned to receive the hepatitis E virus vaccine in either the accelerated group (0, 7 and 21 days) or the routine group (0, 1 and 6 months). Serology samples were obtained at 0, 21, 28 and 51 days, and 7 months in the accelerated group, or 0, 1, 2 and 7 months in the routine group after the first vaccine injection. Adverse events (AEs) reported during the whole study were analysed.ResultsA total of 126 participants were randomized, 63 for each group. Sixty-two participants in the accelerated group and 63 in the routine group received at least one dose of vaccine; 57 and 63 participants received all three doses and were included in per-protocol set, respectively. In the per-protocol population, at 1 month after the last dose (accelerated group at 51 days versus routine group at 7 months), the seropositive rates were both 100% (57/57 and 63/63, respectively), and the geometric mean concentrations (GMCs) were 8.51 WHO units/mL (95% CI 6.73–10.76) in the accelerated group and 9.67 WHO units/mL (95% CI 7.67–12.20) in the routine group. The ratio of the accelerated group GMC to the routine group GMC was 0.88 (95% CI 0.61–2.17, lower limit of 95% CI > 0.5), indicating that the accelerated vaccination schedule was non-inferior to the routine one. The overall incidence rates of solicited AEs in the accelerated and routine groups were 32.26% (20/62) and 30.16% (19/63), respectively (p 0.800). Most AEs were moderate.ConclusionsAn accelerated schedule is safe and provides protective antibodies in a shorter time compared with the routine schedule. The accelerated schedule should be recommended to adults who are travelling on short notice to an HE-endemic area or during an HE outbreak (Clinical Trial Registration. NCT03168412)