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Late Age (late + age)
Selected AbstractsAn autosomal dominant genetically heterogeneous variant of rolandic epilepsy and speech disorderEPILEPSIA, Issue 6 2008Steven L. Kugler Summary We report a three generation pedigree with 11 of 22 affected with a variant form of rolandic epilepsy, speech impairment, oromotor apraxia, and cognitive deficit. The core features comprised nocturnal rolandic seizures, interictal centrotemporal spike waves with early age of onset and late age of offset. The transmission of the phenotype was consistent with autosomal dominant inheritance, with variable expressivity but no evidence of anticipation. We found evidence that the seizure and speech traits may be dissociated. No abnormalities were found by cytogenetic analysis. Linkage analysis excluded loci at 11p, 15q, 16p12, and Xq22 for related phenotypes, suggesting genetic heterogeneity. [source] Prognostic Factors Affecting Long-Term Retention of Topiramate in Patients with Chronic EpilepsyEPILEPSIA, Issue 3 2000S. D. Lhatoo Summary: Purpose: To determine the long-term retention rate of topiramate (TPM) therapy in patients with chronic epilepsy and to identify the relevant prognostic factors that influence retention. Methods: All patients with chronic epilepsy (n = 393) prescribed TPM between October 1, 1995, and December 31, 1998, at a tertiary referral centre for epilepsy were analysed. The retention rate for TPM was calculated by using Kaplan-Meier survival analysis, and the prognostic factors influencing retention were analysed by using Cox regression. Results: Of patients prescribed TPM, 30% continued taking the drug beyond 3 years. Discontinuation was mainly due to adverse events and lack of efficacy. Use of more than one new concurrent antiepileptic drug (AED) and lower maximal daily doses were more likely to result in treatment discontinuation due to adverse events. Older age at onset of epilepsy, a history of having previously taken more than one new AED [lamotrigine (LTG), gabapentin (GBP), or vigabatrin (VGB)], and lower maximal daily doses were more likely to lead to discontinuation due to lack of efficacy. Conclusions: A third of patients with chronic epilepsy started on TPM therapy will continue on treatment for >3 years. Absence of learning disabilities, late age at onset of seizures, previous use of more than one new AED, two or more concurrent AED use, and low maximal daily doses of TPM are more likely to result in discontinuation of medication. These factors should be taken into account when considering the use of TPM for the treatment of chronic epilepsy. [source] Caloric restriction for longevity: I. Paradigm, protocols and physiological findings in animal researchEUROPEAN EATING DISORDERS REVIEW, Issue 5 2004Kelly M. Vitousek Abstract The initial article in this series reviews basic findings in the field of caloric restriction for longevity (CRL). To eating disorder specialists, the data are disconcerting. The chronic dieting and subnormal weight we endeavour to prevent and treat in humans appear highly beneficial when imposed on animals. In the laboratory, organisms from nematodes to monkeys thrive when forced to undereat, as long as they receive sufficient micronutrients. The most remarkable results are obtained through the most extreme measures: mice, for example, do best if limited to a third of expected caloric intake, beginning soon after weaning and continuing throughout adulthood. Deprivation can be achieved through an ,anorexic' protocol of steady underconsumption or a ,bulimic' pattern in which periods of fasting alternate with bouts of binge eating. The benefits of such regimens include delayed senescence, postponement and/or attenuation of age-related disease and dramatic increases in average and maximum lifespan. Although some biological functions are impaired (including growth, reproduction and perhaps resistance to certain stressors), the cost/benefit ratio clearly favours CRL when calculated on the basis of physical outcomes in late age. Advocacy of comparable regimens for people, however, is ill-considered. Enthusiasm for CRL can be sustained only by detaching deprivation from the context of daily life, ignoring psychological effects, and dismissing data on human semi-starvation and eating disorders. The experiences of participants in Biosphere 2 and individuals with anorexia nervosa suggest that the price of CRL is unacceptably high when a wider range of outcome variables is examined. Copyright © 2004 John Wiley & Sons, Ltd and Eating Disorders Association. [source] Interactions between genetic and reproductive factors in breast cancer risk in a population-based sample of African-American familiesGENETIC EPIDEMIOLOGY, Issue 4 2002Valérie Chaudru Abstract Incidence of breast cancer (BC) varies among ethnic groups, with higher rates in white than in African-American women. Until now, most epidemiological and genetic studies have been carried out in white women. To investigate whether interactions between genetic and reproductive risk factors may explain part of the ethnic disparity in BC incidence, a genetic epidemiology study was conducted, between 1989 and 1994, at the Howard University Cancer Center (Washington, DC), which led to the recruitment of 245 African-American families. Segregation analysis of BC was performed by use of the class D regressive logistic model that allows for censored data to account for a variable age of onset of disease, as implemented in the REGRESS program. Segregation analysis of BC was consistent with a putative dominant gene effect (P < 0.000001) and residual sister-dependence (P < 0.0001). This putative gene was found to interact significantly with age at menarche (P = 0.048), and an interaction with a history of spontaneous abortions was suggested (P = 0.08). A late age at menarche increased BC risk in gene carriers but had a protective effect in non-gene carriers. A history of spontaneous abortions had a protective effect in gene carriers and increased BC risk in non-gene carriers. Our findings agree partially with a similar analysis of French families showing a significant gene × parity interaction and a suggestive gene × age at menarche interaction. Investigating gene × risk factor interactions in different populations may have important implications for further biological investigations and for BC risk assessment. Genet. Epidemiol. 22:285,297, 2002. © 2002 Wiley-Liss, Inc. [source] Neural basis of first and second language processing of sentence-level linguistic prosodyHUMAN BRAIN MAPPING, Issue 2 2007Jackson Gandour Abstract A fundamental question in multilingualism is whether the neural substrates are shared or segregated for the two or more languages spoken by polyglots. This study employs functional MRI to investigate the neural substrates underlying the perception of two sentence-level prosodic phenomena that occur in both Mandarin Chinese (L1) and English (L2): sentence focus (sentence-initial vs. -final position of contrastive stress) and sentence type (declarative vs. interrogative modality). Late-onset, medium proficiency Chinese-English bilinguals were asked to selectively attend to either sentence focus or sentence type in paired three-word sentences in both L1 and L2 and make speeded-response discrimination judgments. L1 and L2 elicited highly overlapping activations in frontal, temporal, and parietal lobes. Furthermore, region of interest analyses revealed that for both languages the sentence focus task elicited a leftward asymmetry in the supramarginal gyrus; both tasks elicited a rightward asymmetry in the mid-portion of the middle frontal gyrus. A direct comparison between L1 and L2 did not show any difference in brain activation in the sentence type task. In the sentence focus task, however, greater activation for L2 than L1 occurred in the bilateral anterior insula and superior frontal sulcus. The sentence focus task also elicited a leftward asymmetry in the posterior middle temporal gyrus for L1 only. Differential activation patterns are attributed primarily to disparities between L1 and L2 in the phonetic manifestation of sentence focus. Such phonetic divergences lead to increased computational demands for processing L2. These findings support the view that L1 and L2 are mediated by a unitary neural system despite late age of acquisition, although additional neural resources may be required in task-specific circumstances for unequal bilinguals. Hum. Brain Mapp, 2007. © 2006 Wiley-Liss, Inc. [source] Parent age differentially influences offspring size over the course of development in Laysan albatrossJOURNAL OF ZOOLOGY, Issue 1 2008D. C. Dearborn Abstract Offspring growth and survival are predicted to be higher for older parents, due to a variety of mechanisms, such as increased breeding experience or greater investment favored by low residual reproductive value. Yet the extent to which parent age affects offspring viability is likely to vary between different aspects of growth and survival, perhaps being most pronounced at the most stressful stages of reproduction. We studied the link between parent age and nestling growth and survival in the Laysan albatross, a long-lived seabird with a mean first breeding age of 8 years. Offspring of older parents were more likely to survive to fledging. Among those that did fledge, nestlings of older parents grew more rapidly. However, parent age did not influence the eventual asymptotic size that nestlings reached before fledging: fast-growing nestlings of older parents reached 90% of asymptotic size roughly 1 week sooner, but slow-growing nestlings of younger parents eventually caught up in size before fledging. Older parents bred c. 2 days earlier than younger parents, but hatch date did not explain observed variation in offspring success. The extent to which parent age accounted for variation in size of individual nestlings was not constant but peaked near the midpoint of development. This could reflect a time period when demands on parents reveal age-based differences in parental quality. Overall, growth and survival of offspring increased with parent age in this species, even though the late age of first breeding potentially provides a 7-year period for birds to hone their foraging skills or for selection to eliminate low-quality individuals. [source] Spinocerebellar ataxia type 12 identified in two Italian families may mimic sporadic ataxia,MOVEMENT DISORDERS, Issue 9 2010Alessandro Brussino MD Abstract SCA12 is an autosomal dominant cerebellar ataxia characterized by onset in the fourth decade of life with action tremor of arms and head, mild ataxia, dysmetria, and hyperreflexia. The disease is caused by an expansion of ,51 CAGs in the 5, region of the brain- specific phosphatase 2 regulatory subunit B-beta isoform (PPP2R2B) gene. SCA12 is very rare, except for a single ethnic group in India. We screened 159 Italian ataxic patients for SCA12 and identified two families that segregated an expanded allele of 57 to 58 CAGs, sharing a common haplotype. The age at onset, phenotype, and variability of symptoms were compatible with known cases. In one family, the disease was apparently sporadic due to possible incomplete penetrance and/or late age at onset. Our data indicate that SCA12 is also present in Italian patients, and its genetic testing should be applied to both sporadic and familial ataxias. © 2010 Movement Disorder Society [source] Fetal programming: Adaptive life-history tactics or making the best of a bad start?AMERICAN JOURNAL OF HUMAN BIOLOGY, Issue 1 2005James Holland Jones Fetal programming is an ontogenetic phenomenon of increasing interest to human biologists. Because the downstream consequences of fetal programming have clear impacts on specific life-history traits (e.g., age at first reproduction and the general age-pattern of reproductive investments), a number of authors have raised the question of the adaptive significance of fetal programming. In this paper, I review in some detail several classical models in life-history theory and discuss their relative merits and weaknesses for human biology. I suggest that an adequate model of human life-history evolution must account for the highly structured nature of the human life cycle, with its late age at first reproduction, large degree of iteroparity, highly overlapping generations, and extensive, post-weaning parental investment. I further suggest that an understanding of stochastic demography is essential for answering the question of the adaptive significance of fetal programming, and specifically the finding of low birth weight on smaller adult body size and earlier age at first reproduction. Using a stage-structured stochastic population model, I show that the downstream consequences of early deprivation may be "making the best of a bad start" rather than an adaptation per se. When a high-investment strategy entails survival costs, the alternate strategy of early reproduction with relatively low investment may have higher fitness than trying to play the high-investment strategy and failing. Am. J. Hum. Biol. 17:22,33, 2005. © 2004 Wiley-Liss, Inc. [source] Reproductive aging in captive and wild common chimpanzees: factors influencing the rate of follicular depletionAMERICAN JOURNAL OF PRIMATOLOGY, Issue 4 2009Sylvia Atsalis Abstract We examine and discuss evidence of contrasting differences in fertility patterns between captive and wild female chimpanzees, Pan troglodytes, as they age; in the wild females reproduce in their 40s, but captive studies suggest that menopause occurs around that time. Thus, despite the increased longevity generally observed in captive populations reproductive life span is shortened. We outline a hypothesis to explain the apparent differential pace of reproductive decline observed between wild and captive populations. The breeding schedules of captive primates may contribute to accelerated reproductive senescence because continuous cycling in captive animals results in early depletion of the ovarian stock and premature senescence. Available evidence supports the hypothesis that women with patterns of high oocyte loss experience earlier menopause. Chimpanzees in captivity live longer, and thus, similar to humans, they may experience follicular depletion that precedes death by many years. In captivity, chimpanzees typically have an early age at menarche and first birth, shorter interbirth intervals associated with short lactational periods as young mature faster, and nursery rearing, which allows mothers to begin cycling earlier. Variables typical of wild chimpanzee populations, including late age at menarche and first birth, long interbirth intervals associated with prolonged lactational periods, and a long period of female infertility after immigration, spare ovulations and may be responsible for the later age at reproductive termination. Finally, we describe and discuss the timing of specific reproductive landmarks that occur as female chimpanzees age, distinguishing between functional menopause (age at last birth) and operational menopause (end of cycling). Am. J. Primatol. 71:271,282, 2009. © 2008 Wiley-Liss, Inc. [source] Reef shark declines in remote atolls highlight the need for multi-faceted conservation actionAQUATIC CONSERVATION: MARINE AND FRESHWATER ECOSYSTEMS, Issue 5 2010Nicholas A. J. Graham Abstract 1.The decline of large-bodied predatory species in the oceans is a concern both from a sustainability perspective and because such species can have important ecological roles. Sharks are particularly vulnerable to fishing as their life histories are characterized by late age at maturity, large body size, and low fecundity. 2.Substantial shark population declines have been documented for a number of coastal and pelagic systems, with high population abundance limited to a few remote locations. The relative abundance and composition of reef shark populations are assessed from 1975 to 2006 at a remote, largely uninhabited, group of atolls in the central Indian Ocean; the Chagos Archipelago. 3.Number of sharks observed per scientific dive declined from a mean of 4.2 in the 1970s to 0.4 in 2006, representing a decline of over 90%. Silvertip sharks displayed an increase in abundance from 1996, whereas blacktip and whitetip reef sharks were rarely encountered in 2006. 4.Poaching in the archipelago, is the most likely cause of these declines, highlighted by a number of illegal vessels containing large numbers of sharks arrested since 1996. The data highlight that shark populations, even in remote, otherwise pristine, marine areas, are vulnerable to distant fishing fleets, and a range of strategies will need to be used in concert for their conservation. Copyright © 2010 John Wiley & Sons, Ltd. [source] Managing global shark fisheries: suggestions for prioritizing management strategiesAQUATIC CONSERVATION: MARINE AND FRESHWATER ECOSYSTEMS, Issue 4 2005Michael J. Barker Abstract 1.Over the past two decades the number of fisheries targeting shark resources has increased dramatically. A combination of factors, including relatively slow growth rate, low fecundity and late age of maturity, result in low recovery rates from exploitation for most shark species. This, in turn, is reflected in the poor record of sustainability of shark fisheries. 2.One of the greatest challenges is to find a way to deal with the substantial levels of shark bycatch taken in many non-target fisheries. Poor general recording of shark landings and paucity of shark landing data at the species level also undermine the development of effective shark management strategies.3. This paper reviews the problems that must be faced worldwide if shark resources are to be managed sustainably and lays out a comprehensive set of prioritized management strategies to facilitate the sustainable management of global shark fisheries. It is acknowledged that the majority of sharks are harvested in developing countries and that the management of shark resources in developing and developed countries will need to incorporate different management strategies relevant to local socio-economic agendas. The management recommendations deal with methods to improve the global regulation of fisheries, ways to improve global conservation ethics and encourage active participation in management, as well as means by which specific management strategies may be implemented. Copyright © 2004 John Wiley & Sons, Ltd. [source] Darwinian fitness, evolutionary entropy and directionality theoryBIOESSAYS, Issue 11 2005Klaus Dietz Two recent articles1,2 provide computational and empirical validation of the following analytical fact: the outcome of competition between an invading genotype and that of a resident population is determined by the rate at which the population returns to its original size after a random perturbation. This phenomenon can be quantitatively described in terms of the demographic parameter termed "evolutionary entropy", a measure of the variability in the age at which individuals produce offspring and die. The two articles also validate certain predictions of directionality theory, an evolutionary model that integrates demography and ecology with population genetics. In particular, directionality theory predicts that in populations that spend the greater part of their life cycle in the stationary growth phase, evolution will result in an increase in entropy. These species will be described by a late age of sexual maturity, small progeny sets and a broad reproductive time-span. In populations that undergo large fluctuations in size, however, the evolutionary outcome will be different. When the average size is large, evolution will result in a decrease in entropy,these populations will be described by early age of sexual maturity, large numbers of offspring and narrow reproductive span but when the average size is small, the evolutionary outcome will be random and non-directional. BioEssays 27:1097,1101, 2005. © 2005 Wiley Periodicals, Inc. [source] Bullous pemphigoid in pregnancy: contrasting behaviour in two patientsBRITISH JOURNAL OF DERMATOLOGY, Issue 6 2001B.C. Gee Bullous pemphigoid (BP) is an increasingly common immunobullous disease of the elderly, and, due to the late age of onset, is rarely seen in women of fertile age. Consequently, to the best of our knowledge no cases of BP in pregnancy have been described. We present two cases of BP that have differed in disease behaviour during pregnancy. [source] Age of sitting unsupported and independent walking in very low birth weight preterm infants with normal motor development at 2 yearsACTA PAEDIATRICA, Issue 11 2009MA Marín Gabriel Abstract Aims:, The aims of this study is to (i) determine the age of sitting unsupported and independent walking in preterm infants with birth weight under 1500 g (very low birth weight, VLBW); (ii) estimate differences between VLBW children and a reference population and (iii) estimate the association between clinical characteristics and late age at sitting and walking. Methods:, A longitudinal study was conducted of a cohort of 876 children with VLBW. The World Health Organization (WHO) motor development study population was used as a reference. Ages for both skills were established by interview with parents. Means were compared with t -test, ANOVA and Bonferroni adjustment where appropriate. Results:, The inclusion criteria were complied with 694 patients; 50% of VLBW sat at 7 m corrected age (CA) and walked at 13 m CA. Both motor skills were acquired later (7.3 ± 1.5 and 13.6 ± 2.8 m) compared with the control group (6 ± 1.1 and 12.1 ± 1.8 m). Weight or head circumference at birth below the 10th percentile or the presence of bronchopulmonary dysplasia were associated with delayed acquisition of both skills. Conclusion:, Very low birth weight infants typically sit unsupported and walk later than term infants. Tables describing reference values for milestones acquisition for different categories of infants (gestational age, birth weight and other determinants) may contribute to inform the decision making process on access to available resources. [source] Evolution of late-life fecundity in Drosophila melanogasterJOURNAL OF EVOLUTIONARY BIOLOGY, Issue 1 2006C. L. RAUSER Abstract Late-life fecundity has been shown to plateau at late ages in Drosophila analogously to late-life mortality rates. In this study, we test an evolutionary theory of late life based on the declining force of natural selection that can explain the occurrence of these late-life plateaus in Drosophila. We also examine the viability of eggs laid by late-age females and test a population genetic mechanism that may be involved in the evolution of late-life fecundity: antagonistic pleiotropy. Together these experiments demonstrate that (i) fecundity plateaus at late ages, (ii) plateaus evolve according to the age at which the force of natural selection acting on fecundity reaches zero, (iii) eggs laid by females in late life are viable and (iv) antagonistic pleiotropy is involved in the evolution of late-life fecundity. This study further supports the evolutionary theory of late life based on the age-specific force of natural selection. [source] | |||||||||||||