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Older Males (older + male)
Selected AbstractsThe carotenoid-based plumage coloration of adult Blue Tits Cyanistes caeruleus correlates with the health status of their broodIBIS, Issue 4 2006SERGIO HIDALGO-GARCIA The Blue Tit Cyanistes caeruleus is a passerine bird in which both sexes provide substantial care to the offspring and display conspicuous carotenoid-based plumage coloration. It has been shown that carotenoid-based coloration in birds reflects both individual quality and foraging ability. Because the body condition of nestlings usually depends on the capacity of their parents to feed them, I predicted that, independent of sex, those individuals with the most exaggerated carotenoid-based plumage coloration should raise offspring in better health. I found that although, in my study population, the smallest females were paired with the largest males, the brightest females were paired with the brightest and most intensely coloured males. I used body condition and T-cell-mediated immune response of nestlings as measures of their health status. Generalized mixed models showed that brighter and more-yellow adults reared offspring in better than average condition and immune response. Older males and smaller females were also able to raise offspring with better immune response. All these results suggest that the carotenoid-based plumage coloration of parents is somehow linked with individual quality, as it presents a significant and positive correlation with the health status of their growing chicks. Thus, the brightest and more intensely coloured individuals raised the healthiest offspring. [source] Age-related patterns of reproductive success in house sparrows Passer domesticusJOURNAL OF AVIAN BIOLOGY, Issue 5 2007Margret I. Hatch A common life history pattern in many organisms is that reproductive success increases with age. We report a similar pattern in house sparrows Passer domesticus, older individuals performed better than yearlings for most measures of reproductive success. Older males and females began breeding earlier in a given season and fledged more young than their yearling counterparts. Individual males also fledged more young in their second breeding season than they did in their first, but individual females did not show consistent improvement in reproductive success from year one to two. A path analysis indicated that age in both sexes acted primarily through the timing of breeding; earlier nesters laid more eggs and hence fledged more young but did not have more nesting attempts. We tested whether the increased reproductive success with age arose from high quality individuals surviving to be older (selection hypothesis). In contrast to the main prediction of this hypothesis that reproductive success and survival should be positively related, we found that survival from one year of age to two years of age was negatively related to reproductive success in the first year for males and females combined. Additionally, individuals that survived to breed as two-year-olds did not differ in total young fledged in their first year from those that did not survive to their second season of breeding. Our results indicate that fledgling production increases with age due to improvements in timing of breeding, particularly in females, and not because of the loss of poor breeders or increased output. Mechanisms producing age-related differences in timing of breeding warrant further study. [source] Sexual-Minority and Heterosexual Youths' Peer Relationships: Experiences, Expectations, and Implications for Well-BeingJOURNAL OF RESEARCH ON ADOLESCENCE, Issue 3 2004Lisa M. Diamond The current study compared the peer relationships and well-being of 60 sexual-minority (i.e., nonheterosexual) and 65 heterosexual youths between the ages of 15 and 23. Sexual-minority youths had comparable self-esteem, mastery, and perceived stress as did heterosexuals, but greater negative affect. Younger sexual-minority male adolescents had smaller overall peer networks than did young male heterosexuals, whereas older male and female sexual minorities had larger numbers of extremely close friends within their networks than did heterosexuals. Younger sexual-minority adolescents had lost or drifted away from more friends than did heterosexuals. Regardless of age, sexual-minority youths reported disproportionately high worries about losing friends, low feelings of control in their romantic relationships, and fears of never finding the type of romantic relationship they wanted. Sexual-minority youths that were "out" to more heterosexual peers had larger peer networks but more friendship loss and friendship worries. Youths' relationship experiences and concerns mediated sexual identity differences in negative affect. [source] Measurement of testosterone in the diagnosis of hypogonadism in the ageing maleCLINICAL ENDOCRINOLOGY, Issue 4 2008M. J. Wheeler Summary Many males in their old age demonstrate symptoms consistent with hypogonadism. With the introduction of new and more convenient methods of testosterone replacement treatment of these males is more practical. The diagnosis of hypogonadism in the older male has been controversial with some clinicians suggesting that symptoms should be treated without due reliance on testosterone concentrations. However, most professional bodies have proposed that a low testosterone concentration should be part of the diagnosis. This is, in turn, reliant on the testosterone measurement being reliable and read against an appropriate reference range. This review looks at the factors that can influence the interpretation of testosterone results for the ageing male. [source] Syllable repertoire and the size of the song control system in captive canaries (Serinus canaria)DEVELOPMENTAL NEUROBIOLOGY, Issue 1 2004Stefan Leitner Abstract In songbirds, there is considerable interest in relationships between song structure and the size of the song control system in the forebrain. In male canaries, earlier studies have reported that repertoire size increased with age, and positive correlations were obtained between repertoire size and the volume of song control nuclei such as high vocal center (HVC). Here we investigate whether age has an effect upon both the song structure and the morphology of two song control nuclei [HVC and robustus archistriatalis (RA)] that are important in song production. We recorded songs from an aviary population of 1- and 2-year-old male domesticated canaries. We found that repertoire size, number of sexually attractive (sexy) syllables, and size of song nuclei did not differ between 1- and 2-year-old males. Neither did we find significant correlations between syllable repertoire size and the size of the song control nuclei. However, HVC size was positively correlated with the proportion of sexy syllables in the repertoires of 2-year-old males. Some older males may enhance vocal performance by modifying the control of syllables rather than by increasing repertoire size or neural space. © 2004 Wiley Periodicals, Inc. J Neurobiol 60: 21,27, 2004 [source] Exploratory behavior in mice selectively bred for developmental differences in aggressive behaviorDEVELOPMENTAL PSYCHOBIOLOGY, Issue 1 2008Kathryn E. Hood Abstract The development and expression of exploratory behavior was assessed in the Cairns lines of Institute for Cancer Research (ICR) mice that were selectively bred for differences in aggressive behavior, with a high-aggressive 900 line, low-aggressive 100 line, and control 500 line. Four paradigms were employed. Developmental changes were evident in the complex novel arena, with older males faster to contact a novel object, and ambulating more than young males. Within the control 500 line, older males showed longer latency to emerge from the home cage, and shorter latency to contact novel objects. In the 900 line, younger males showed this same pattern. R. B. Cairns proposed that line differences in aggressive behavior arise through alterations in developmental timing [Cairns et al. [1983] Life-span developmental psychology (Vol. 5). New York: Academic Press; Gariépy et al. [2001] Animal Behaviour 61: 933,947]. The early appearance of mature patterns of exploratory behavior in 900 line males supports this interpretation. The 900 line males also appear to be behaviorally inhibited in novel settings such as the light,dark box and the neohypophagia paradigm, compared to the 500 and 100 lines (Experiments 1, 2, and 4). Moreover, in the most complex apparatus, the novel arena, 900 line males were slowest to exit the home cage, and fastest to contact a novel object. The apparent contrast in these parameters of exploratory behavior is discussed in relation to T. C. Schneirla's [1965 Advances in the study of behavior (Vol. 1). New York: PN Academic] approach,withdrawal theory. © 2007 Wiley Periodicals, Inc. Dev Psychobiol 50: 32,47, 2008. [source] Health status and labour force participation: evidence from AustraliaHEALTH ECONOMICS, Issue 3 2006Lixin Cai Abstract This paper examines the effect of health on labour force participation using the Household, Income and Labour Dynamics in Australia (HILDA) Survey. The potential endogeneity of health, especially self-assessed health, in the labour force participation equation is addressed by estimating the health equation and the labour force participation equation simultaneously. Taking into account the correlation between the error terms in the two equations, the estimation is conducted separately for males aged 15,49, males aged 50,64, females aged 15,49 and females aged 50,60. The results indicate that better health increases the probability of labour force participation for all four groups. However, the effect is larger for the older groups and for women. As for the feedback effect, it is found that labour force participation has a significant positive impact on older females' health, and a significant negative effect on younger males' health. For younger females and older males, the impact of labour force participation on health is not significant. The null-hypothesis of exogeneity of health to labour force participation is rejected for all groups. Copyright © 2005 John Wiley & Sons, Ltd. [source] Allometry, bilateral asymmetry and sexual differences in the vocal tract of common eiders Somateria mollissima and king eiders S. spectabilisJOURNAL OF AVIAN BIOLOGY, Issue 2 2007Edward H. Miller Intraspecific sexual differences, high variation, and positive allometry of sexually-selected external display structures are common. Many sexually-selected anatomical specializations occur in the avian vocal tract but intraspecific variation and allometry have been investigated little. The tracheal bulla bulla syringealis occurs in males of most duck species. We quantified variation and size-scaling of the bulla, plus sexual differences in size of trachea, bronchi, and vocal muscles, for 62 common eiders Somateria mollissima and 51 king eiders S. spectabilis. Trends were similar in both species. Bullar ossification and definitive size occurred early in life: bullar size did not differ between first-year and older males. Bullar size did not vary more than size of other body parts (CVs of 3.4,7.0% for bullar length and breadth). Bullar size scaled to body size with negative allometry or isometry. Vocal muscles were 10,50% thicker in males than females, a much greater sexual difference than in body size (CVs of 3,6% on linear body-size variables). Vocal muscles were larger on the left side in both sexes and bilateral asymmetry was slightly more pronounced in males. Low variation and a trend towards negative allometry suggest that bullar size is under stabilizing selection; if bullar size affects vocal attributes of voice, then the latter cannot be condition-dependent. We recommend comparative research on vocal communication, vocal individuality and vocal-tract anatomy and function in eiders and other ducks. [source] How female reed buntings benefit from extra-pair mating behaviour: testing hypotheses through patterns of paternity in sequential broodsMOLECULAR ECOLOGY, Issue 9 2006KAREN M. BOUWMAN Abstract Extra-pair paternity is an important aspect of reproductive strategies in many species of birds. Given that in most species females control whether fertilization occurs, they are expected to benefit in some way from the extra-pair matings. In this study we use patterns of extra-pair paternity (EPP) in broods of individual reed buntings (Emberiza schoeniclus), both within and between seasons, to test four hypothesized female benefits: (1) assessing potential future partners and seeking (2) genetic diversity (3) good genes, or (4) compatible genes. Reed buntings are socially monogamous, multibrooded passerines with extremely high levels of extra-pair paternity. We studied a population of reed buntings in the Netherlands in 2002 and 2003; 51% of offspring in 74% of nests were extra-pair. We showed that patterns of EPP did not support the first and second hypotheses, since females did not form a pair with previous extra-pair partners, EPP was not evenly distributed among broods and more broods than expected were sired by a single male. Furthermore, there was no relation between a male's within- and extra-pair fertilization success, no consistency in EPP between breeding attempts, no effect of parental relatedness on EPP and several cases of reciprocal paternity. These patterns do not support the good genes hypothesis and are most consistent with the genetic compatibility hypothesis. However, our previous finding that older males are more successful in gaining EPP, suggests some effect of good genes. These hypotheses need not be mutually exclusive, as females may select compatible males above a certain quality threshold (e.g. old males). [source] Mice lacking cyclin-dependent kinase inhibitor p19Ink4d show strain-specific effects on male reproductionMOLECULAR REPRODUCTION & DEVELOPMENT, Issue 8 2007Gregory M. Buchold Abstract p19Ink4d is a member of the INK4 family of cyclin-dependent kinase inhibitors, which are important negative regulators of the G1-phase cyclin-dependent kinases CDK4 and CDK6. On a mixed C57BL/6,×,129P2/OlaHsd background, mice deficient for p19Ink4d exhibited defects in male reproductive function including testicular atrophy, alteration in serum follicle stimulating hormone, qualitative increase in germ cell apoptosis, and delayed kinetics of meiotic prophase markers (Zindy et al., 2001. Mol Cell Biol 21:3244,3255; Zindy et al., 2000. Mol Cell Biol 20:372,378). In this study, a quantitative assessment of these aspects of reproductive capacity demonstrated relatively mild deficits in p19Ink4d,/, males compared to controls. These effects did not dramatically worsen in older males although some seminiferous tubule defects were observed. Following marker-assisted backcrossing into the C57BL/6 background, p19Ink4d,/, males did not display defects in testis weights, sperm numbers, serum FSH, germ cell apoptosis, or kinetics of selected meiotic prophase markers. These studies indicate that a reduction in Ink4 family function by the loss of p19Ink4d is sufficient to induce mild reproductive defects in male mice with a mixed genetic background, but not in the C57BL/6 genetic background. Mol. Reprod. Dev. 74: 1008,1020, 2007. © 2007 Wiley-Liss, Inc. [source] Changes in social interactions during adolescence in male mandrills (Mandrillus sphinx)AMERICAN JOURNAL OF PRIMATOLOGY, Issue 2 2004Marie Charpentier Abstract The adolescent period in male mandrills extends from the time the testicles descend (at the age of 3,4 years) to the time adult characteristics develop (at the age of 10 years), and is thus one of the longest adolescent periods in cercopithecines. In this short cross-sectional study of 11 male mandrills (4.7,9.1 years old), we analyzed social behavioral patterns to investigate partner preference and changes in types of interactions throughout puberty. The mandrills were separated into two clusters on the basis of all of the social interactions scored, as well as the age and sex of the protagonist. During early to mid puberty, immature individuals interacted preferentially with other male adolescents and juveniles. Playing was an important activity, and some affiliative interactions with juveniles were observed. Older adolescents interacted more with adult males and females. These older adolescents were predominantly aggressive toward other adolescents, females, and juveniles, and showed little or no affiliative or playful behaviors. These results indicate a shift in social partners: older males interacted more frequently with adult males, and their behavior involved more aggression and less submission compared to younger adolescents, which showed predominantly submissive and playful behavior. These changes are consistent with preparation for dispersal and future intermale competition. Am. J. Primatol. 63:63,73, 2004. © 2004 Wiley-Liss, Inc. [source] Routine Screening for Asymptomatic Abdominal Aortic Aneurysm in High-risk Patients Is Not Recommended in Emergency Departments That Are Frequently CrowdedACADEMIC EMERGENCY MEDICINE, Issue 11 2009Beatrice Hoffmann MD Abstract Objectives:, The objectives were to examine the feasibility of offering abdominal aortic aneurysm (AAA) screening to consecutive, asymptomatic high-risk patients in a busy emergency department (ED) and to compare the prevalence of undetected AAA among ED patients to the prevalence among similarly aged men from the general population. Methods:, A prospective cohort study was conducted at an academic community ED with an annual census of 58,000 patients. Dedicated study coordinators attempted to approach all consecutive male ED patients >50 years who presented in June,August 2007 during hours of high patient volume. To be eligible, older males had to have a smoking history or a family history of AAA. Patients were excluded if they presented with AAA symptoms, had a previous history of AAA screening or repair, had hemodynamic instability, or had an altered mental status. Study coordinators completed a brief interview with all enrolled subjects to obtain demographic and health information. A credentialed ED provider performed the ultrasound (US) screening exam and documented all findings. The US director reviewed representative images of the sonographic exam for correct visualization and measurement during quality assurance. The ED sonographers also completed a survey regarding their attitudes toward AAA screening in the ED. The primary study outcomes were the feasibility of AAA screening in the ED (screening rate, enrollment rate, US success rate, and providers' opinions) and the prevalence of AAA (aortic diameter of ,3.0 cm) in the study sample. Results:, During the 12-week study period, the study coordinators successfully approached 96% (700/729) of males > 50 years who were in the ED during study enrollment hours. Of those approached, 278 were eligible (40%), 25% were ineligible, 20% were not at high risk, and for 15% we could not determine risk factor status because of altered mental status. Of the 278 eligible, 196 (70%) underwent an US exam; 10% were not scanned because the providers were too busy, and 20% declined participation. Of those scanned, the ED sonographer was able to completely visualize and correctly measure the abdominal aortas of 71% of subjects. The prevalence rate of AAA in the study sample was 5.7% (95% confidence interval [CI] = 1.9% to 9.6%), similar to reported rates of 6 or 7% in other studies. More than half of the ED sonographers reported that US screening for AAA improved the quality of ED care (58%) and patient satisfaction (63%). However, 47% reported that AAA screening reduced ED efficiency, and 74% felt that the ED was not an appropriate setting for routine AAA screening. Conclusions:, Routine screening for asymptomatic AAA required substantial ED resources for a relatively low success rate of completed screens. The prevalence rate of AAA in our ED sample was not significantly different than prevalence estimates obtained from older men in the general population. ED sonographers reported benefits of screening in terms of improving the quality of emergency care and patient satisfaction, but also reported that it reduced operational efficiency. For EDs that have problems with crowding, we do not recommend implementing a routine screening program for AAA, even among high-risk patients. [source] ANTERIOR TONGUE CANCER: AGE IS NOT A PREDICTOR OF OUTCOME AND SHOULD NOT ALTER TREATMENTANZ JOURNAL OF SURGERY, Issue 11 2003Michael J. Veness Background: Mucosal head and neck cancers usually occur in older males after years of smoking and alcohol abuse. Despite this, approximately 5% of cases occur in young adults. The aetiology remains unclear and the anterior tongue is a prevalent site. Prognosis has been reported as worse in young patients and some have proposed a more aggressive treatment approach. Methods: Patients diagnosed with previously untreated anterior tongue squamous cell carcinoma and treated with curative intent were identified. Retrospective and prospective data were collected. Univariate and multivariate analyses were undertaken using Cox regression analysis. The outcome of patients treated with anterior tongue cancer using a cut-off age of 40 years was compared. Results: Between 1980 and 2000, 106 males and 58 females with anterior tongue squamous cell carcinoma were treated at Westmead Hospital. Median follow up was 47 months (6,210 months). Twenty-two patients (13.4%) were aged ,40 years. Other than age, patient demographics, TNM stage and treatment approach were similar between the two groups. Eighty-one per cent had either a T1 or T2 primary. In total, 139 patients (84.8%) had surgery or surgery and radiotherapy. A total of 56 (34%) patients experienced a recurrent event, with nodal recurrence occurring most often as the first site (n = 33, 59%). Young patients had a higher recurrence rate (45.5% vs 32.4%; P = 0.23). Relapse-free survival at 5 years was 62% versus 81% (P = 0.27). Overall survival at 5 years was 65% versus 67% (P = 0.74). Conclusions: In keeping with recently published evidence, young age at diagnosis with anterior tongue cancer did not portend worse outcome. There is therefore currently no strong evidence to support a different treatment approach in young patients. [source] Pharmacokinetics and pharmacodynamics of TF-505, a novel nonsteroidal 5,-reductase inhibitor, in normal subjects treated with single or multiple dosesBRITISH JOURNAL OF CLINICAL PHARMACOLOGY, Issue 3 2002Tomoe Fujita Aims To assess the tolerability, pharmacokinetics and pharmacodynamics of a novel nonsteroidal,, and,, noncompetitive,, inhibitor,, of,, type,, I,, and,, type,, II,, 5,-reductases, (,)-(S)-4-[1-[4-[1-(4-isobutylphenyl) butoxy]benzoyl]indolizin-3-yl]butyric acid (TF-505), after single and multiple oral doses in healthy volunteers. Methods In the single-dose study, six young adult males in each dose group received 25 mg or 50 mg of TF-505, and six older males (, 40 years) in each dose group received 75 mg or 100 mg of TF-505. The subjects were given the drug in ascending dose and in the fasting state. Six subjects also received 50 mg of TF-505 after breakfast in a two-period crossover manner. In the multiple-dose study, six older males in each dose group received 12.5 mg or 25 mg TF-505 after breakfast daily for 7 days. Plasma concentrations of TF-505, dihydrotestosterone (DHT) and testosterone were measured. The pharmacokinetics of TF-505 were analysed by a compartment model with first-order absorption, first-order elimination and a lag time. Pharmacokinetic and pharmacodynamic relationships were evaluated by indirect response modelling with inhibition of input. Results Maximum plasma concentration (Cmax) and the area under the concentration,time curve (AUC) increased proportionately after the single dose up to 50 mg and with the multiple doses. Linearity was not detected between 75 and 100 mg of TF-505. Dose dependency was also noted for the effect of TF-505 on DHT concentrations following single doses up to 50 mg and multiple doses. Plasma DHT concentrations decreased maximally to 58.2, 49.5, 54.2 and 49.8% of basal values at 8,12 h after single administration of 25, 50, 75 and 100 mg TF-505, respectively, and to 60.5 and 49.4% at the 7th and 5th dose following multiple doses of 12.5 and 25 mg TF-505, respectively. The predicted effect curves matched the observed data when the indirect response model was applied to the time course of the suppressant effect of TF-505 on plasma DHT concentrations after both the single and multiple studies. Fifty percent inhibitory concentrations (IC50) of 0.82, 1.48, 1.31 and 0.88 µ g ml,1, zero-order rate constants for the onset of plasma DHT concentration changes (kin) of 17.8, 17.4, 17.0 and 10.7% h,1 and first-order rate constants,, for,, increase,, in,, plasma,, DHT,, concentrations,, to,, basal,, values,, (kout),, of,, 0.17,,, 0.16,,, 0.17,, and,, 0.10 h,1,, for,, the,, single,, study,, at,, doses,, of,, 25,,, 50,,, 75,, and 100 mg, respectively, were attained. In the multiple-dose study, IC50s were 1.74 and 1.49 µg ml,1 for the 12.5 and 25 mg doses, respectively. No serious adverse events related to TF-505 were observed. Conclusions TF-505 was well tolerated in healthy male volunteers. Accumulation of TF-505 in plasma was not observed during multiple dosing. The indirect response model described the relationships between pharmacokinetics and pharmacodynamics of TF-505. Such modelling is expected to yield an appropriate dosage regimen in subsequent clinical trials. [source] | |||||||||||||