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1.
Environmental experiences during development provide animals with important information about future conditions. Siberian hamsters are photoperiodic rodents that dramatically adjust their physiology and behavior to adapt to seasonal changes. For example, during short winter-like days, hamsters enhance some components of immune function putatively to cope with increasing environmental challenges. Furthermore, early life stress alters the developmental course of the immune system. Overall, immune function is typically suppressed in response to chronic stress, but responses vary depending on the type of stress and components of immune function assessed. This led us to hypothesize that delayed-type hypersensitivity (DTH), an antigen-specific, cell-mediated immune response, would be differentially modulated in hamsters that underwent early life maternal separation (MS) in either short or long photoperiods. At birth, hamsters were assigned to either short (SD; 8?h light/day) or long (LD; 16?h light/day) photoperiods and either daily 3?h MS, daily 15-min brief maternal separation (BMS), or no manipulation from postnatal day 2 through 14. In adulthood DTH was assessed. Hamsters reared in short days enhanced DTH responses. MS and BMS attenuated DTH responses in both short and long days. However, BMS long-day female hamsters did not suppress pinna swelling, suggesting a protective effect of female sex steroids on immune function. As is typical in short days, reproductive tissue was regressed. Reproductive tissue mass was also decreased in long-day MS female hamsters. Furthermore, MS altered photoperiod-induced changes in body mass. Taken together, these findings suggest that manipulations of early life mother-pup interactions in Siberian hamsters result in physiological changes and suppressed cell-mediated immunity. (Author correspondence: ).  相似文献   

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ABSTRACT

The purpose of this study was to investigate whether childhood experiences with family pets are associated with symptoms of depression and anxiety in early adulthood. Undergraduate students (n=318) responded to an online survey that included questions about bonding with childhood pets, exposure to family violence and human aggression directed toward family pets in childhood, and current symptoms of depression and anxiety. Two-way ANCOVAs were conducted with a measure of childhood emotional abuse included as a covariate, and significant interactions were observed between pet bonding and exposure to aggression toward pets (pet aggression). Among participants with medium-level bonds, those who were exposed to pet aggression had significantly higher depression and anxiety scores than those who were not exposed to pet aggression. Among participants who were not exposed to pet aggression, those with medium-level bonds had lower depression and anxiety scores than those with low-level bonds. Bearing in mind the limitations of the research design, the results are consistent with the assertion that bonding with pets may support mental health and that exposure to animal cruelty may lead to the development of internalizing symptoms. The results also support the contention that both bonding with pets and exposure to pet aggression should be considered when investigating the association between experiences with pets and mental health. Interventions for the protection of children may be indicated in cases of animal cruelty. Social workers who investigate child maltreatment may be advised to refer children who are exposed to animal cruelty for counseling. Clinicians should consider addressing issues that arise from exposure to pet aggression during the therapeutic process.  相似文献   

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We test the idea that male colour polymorphism in a lizard (red vs. yellow headed) may be maintained by a female preference for associating (and presumably mating) with both male morphs rather than only one. In female choice experiments on single males of different colours, females did not preferentially associate with either morph. However, when females were allowed to choose between pairs of males of the same vs. different colours, they preferred to associate with male pairs that were polymorphic. We suggest that this may be the result of selection arising from polyandrous mating benefits and show experimentally that polyandry results in increased hatching success. Most theoretical models of the evolution of mate choice assume that mate choice is costly. We test this assumption by releasing females into polymorphic vs. monomorphic groups in the wild, under the hypothesis that females move more between males in polymorphic groups and therefore suffer higher risks of mortality from predation. In accordance with this prediction, females released into polymorphic male groups were less likely to be recaptured than females released into monomorphic groups, with evidence to suggest that this is because of increased mortality and not increased dispersal. We propose that this cost could be (partly) balanced by polyandrous fitness benefits.  相似文献   

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生命之初     
我们大家都知道人是由猿演变来的,那么猿又是从哪里来的,最初的生命是什么样的,这要追溯到遥远的古代。46亿年前地球形成了,它不停地自转,又绕着太阳公转.一直转了17亿年,这个时候的地球陆地上还是一片荒芜死气,海洋却孕育了生命,它就是最原始的细胞。  相似文献   

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The sense of touch provides fundamental information about the surrounding world, and feedback about our own actions. Although touch is very important during the earliest stages of life, to date no study has investigated infants’ abilities to process visual stimuli implying touch. This study explores the developmental origins of the ability to visually recognize touching gestures involving others. Looking times and orienting responses were measured in a visual preference task, in which participants were simultaneously presented with two videos depicting a touching and a no-touching gesture involving human body parts (face, hand) and/or an object (spoon). In Experiment 1, 2-day-old newborns and 3-month-old infants viewed two videos: in one video a moving hand touched a static face, in the other the moving hand stopped before touching it. Results showed that only 3-month-olds, but not newborns, differentiated the touching from the no-touching gesture, displaying a preference for the former over the latter. To test whether newborns could manifest a preferential visual response when the touched body part is different from the face, in Experiment 2 newborns were presented with touching/no-touching gestures in which a hand or an inanimate object—i.e., a spoon- moved towards a static hand. Newborns were able to discriminate a hand-to-hand touching gesture, but they did not manifest any preference for the object-to-hand touch. The present findings speak in favour of an early ability to visually recognize touching gestures involving the interaction between human body parts.  相似文献   

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表观遗传学(epigenetics)是指不涉及DNA序列改变、可以通过有丝分裂和减数分裂进行遗传的基因表达变化的遗传学分支领域。目前研究主要集中在DNA甲基化、组蛋白密码、染色质重塑和非编码RNA调控等方面。早期负性经历是指个体出生早年所经历的不良生活事件,还包括个体出生前所经历的负性生活事件。大量研究表明早期负性经历对个体成年后的行为会造成明显影响。本文将综述早期负性经历中表观遗传的各种机制。  相似文献   

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表观遗传学(epigenetics)是指不涉及DNA序列改变、可以通过有丝分裂和减数分裂进行遗传的基因表达变化的遗传学分支领域。目前研究主要集中在DNA甲基化、组蛋白密码、染色质重塑和非编码RNA调控等方面。早期负性经历是指个体出生早年所经历的不良生活事件,还包括个体出生前所经历的负性生活事件。大量研究表明早期负性经历对个体成年后的行为会造成明显影响。本文将综述早期负性经历中表观遗传的各种机制。  相似文献   

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Introduction/Aim

Haemophilia is caused by deficiency in coagulation factor VIII or IX. Treatment with the missing coagulation factors has been available in most developed countries for several decades. The aim was to explore the experiences of adults living with severe or moderate haemophilia and their coping strategies at a single centre in Sweden.

Method

The interview study had a qualitative empirical approach and was analyzed on the basis of the method empirical phenomenological psychology. The sample included 14 participants, mean age 42 (19–80 y), who met the inclusion criteria and to saturation of information. Results: General characteristics were; All were satisfied with and grateful for access to medication. An acceptance of the disorder and willingness to live a normal life was identified among all participants. They were all content with the care provided by Haemophilia Treatment Centre (HTC) and felt supported by its multidisciplinary team. Four typologies were identified; Protective adults and assertive children during up-bringing, finding a role in social context, symptoms and treatments, fear of limited resources in the future. Task-, emotional- and avoidance coping strategies were seen in the interviews. The most prominent coping strategy was task oriented.

Conclusion

This interview study with Swedish PWH shows that they strive for normality and adaptation in social activities throughout life finding their own niche. The PWH expressed the importance of knowledge and support from the comprehensive medical team at HTC and therefore it seems important to continue comprehensive medical care at HTC in order to follow-up the haemophilia persons regularly.  相似文献   

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Moshe Szyf 《遗传学报》2013,40(7):331-338
The impact of early physical and social environments on life-long phenotypes is well known. Moreover, we have documented evidence for gene–environment interactions where identical gene variants are associated with different phenotypes that are dependent on early life adversity. What are the mechanisms that embed these early life experiences in the genome? DNA methylation is an enzymatically-catalyzed modification of DNA that serves as a mechanism by which similar sequences acquire cell type identity during cellular differentiation and embryogenesis in the same individual. The hypothesis that will be discussed here proposes that the same mechanism confers environmental-exposure specific identity upon DNA providing a mechanism for embedding environmental experiences in the genome, thus affecting long-term phenotypes. Particularly important is the environment early in life including both the prenatal and postnatal social environments.  相似文献   

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Maternal obesity induced by a high fat (HF) diet may program susceptibility in offspring, altering pancreatic development and causing later development of chronic degenerative diseases, such as obesity and diabetes. Female mice were fed standard chow (SC) or an HF diet for 8 weeks prior to mating and during the gestational and lactational periods. The male offspring were assessed at birth, at 10 days, and at 3 months of age. The body mass (BM) gain was 50% greater before pregnancy and 80% greater during pregnancy in HF dams than SC dams. Dams fed an HF diet showed higher oral glucose tolerance test (OGTT), blood pressure, serum corticosterone, and insulin levels than dams fed SC. At 10 days of age and at 3 mo old the HF offspring showed greater BM and higher blood glucose levels than the SC offspring. The mean diameter of the islets had increased by 37% in the SC offspring and by 155% in the HF offspring at 10 days of age. The islet mass ratio (IM/PM) was 88% greater in the HF offspring at 10 days of age, and 107% greater at 3 mo of age, compared to the values obtained at birth. The HF offspring had a beta cell mass (BCM)/PM ratio 54% lower than SC offspring at birth. However, HF offspring displayed a 146% increase in the BCM/PM ratio at 10 days of age, and 112% increase at 3 months of age than values at birth. A 3 mo of age, the HF offspring showed a greater OGTT and higher levels of than SC offspring. In conclusion, a maternal HF diet consumed during the preconceptional period and throughout the gestational and lactational periods in mice results in dramatic alterations in the pancreata of the offspring.  相似文献   

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目的:探讨运动康复锻炼对冠心病经皮冠状动脉介入术(PCI)后患者心肺功能及生活质量的影响。方法:选取2016年10月-2018年4月期间我院收治的冠心病稳定性心绞痛患者80例,根据随机数字表法将患者分为对照组(n=40)和运动康复组(n=40),其中对照组给予常规康复运动,运动康复组在此基础上联合运动康复训练。比较两组患者术后12周的心肺功能指标,比较两组患者术前、术后2周、术后12周的6 min步行距离,比较两组患者术前、术后12周生活质量评分。结果:运动康复组患者术后12周峰值摄氧量、峰值通气量、峰值功率、每搏输出量、代谢当量以及摄氧效率斜率均高于对照组患者(P0.05)。两组患者术后2周、术后12周6 min步行距离均较术前增加,且运动康复组高于对照组(P0.05)。两组患者术后12周生理机能、生理职能、躯体疼痛、精神健康评分均较术前升高,且运动康复组高于对照组(P0.05);而两组患者术后12周社会功能、总体健康、精力、情感职能评分比较差异无统计学意义(P0.05)。结论:PCI术后患者给予运动康复锻炼,可显著提升患者生活质量,对患者心肺功能恢复具有较好的促进作用。  相似文献   

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BackgroundThe role of the natriuretic peptides (NPs) in hypertension is complex. Thus, a higher blood NP concentration is a robust marker of pressure-induced cardiac damage in patients with hypertension, whereas genetically elevated NP concentrations are associated with a reduced risk of hypertension and overweight individuals presumably at high risk of hypertension have lower NP concentrations.ObjectiveTo investigate the associations between serum N-terminal pro-B-type natriuretic peptide (NT-proBNP), used as a surrogate marker for active BNP, and prevalent as well as 5-year incident hypertension in a Danish general population sample.MethodsCross-sectional and prospective population-based study.ResultsAt baseline, among 5,307 participants (51.3% women, mean age 46.0±7.9 years) with a complete set of data, we recorded 1,979 cases with prevalent hypertension (PHT). Among 2,389 normotensive participants at baseline with a complete set of data, we recorded 324 cases with incident hypertension (IHT) on follow-up 5 years later. In models adjusted for age, sex, lifestyle, social, dietary, anthropometric, pulmonic, lipid, metabolic and renal risk factors, as well as heart rate and baseline blood pressure (only incident model), one standard deviation increase in baseline log-transformed NT-proBNP concentrations was on one side associated with a 21% higher risk of PHT (odds ratio [OR]: 1.21 [95% confidence interval (CI): 1.13-1.30], P<0.001), and on the other side with a 14% lower risk of IHT (OR: 0.86 [95%CI:0.76-0.98], P = 0.020).ConclusionsHigher serum concentrations of NT-proBNP associate with PHT whereas lower concentrations associate with IHT. This suggests that a lower amount of circulating BNP, resulting in diminished vasodilation and natriuresis, could be involved in the pathogenesis of hypertension in its early stages.  相似文献   

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Immunoglobulin A deficiency (IgAD) is the most common primary immune deficiency disorder in both humans and dogs, characterized by recurrent mucosal tract infections and a predisposition for allergic and other immune mediated diseases. In several dog breeds, low IgA levels have been observed at a high frequency and with a clinical resemblance to human IgAD. In this study, we used genome-wide association studies (GWAS) to identify genomic regions associated with low IgA levels in dogs as a comparative model for human IgAD. We used a novel percentile groups-approach to establish breed-specific cut-offs and to perform analyses in a close to continuous manner. GWAS performed in four breeds prone to low IgA levels (German shepherd, Golden retriever, Labrador retriever and Shar-Pei) identified 35 genomic loci suggestively associated (p <0.0005) to IgA levels. In German shepherd, three genomic regions (candidate genes include KIRREL3 and SERPINA9) were genome-wide significantly associated (p <0.0002) with IgA levels. A ~20kb long haplotype on CFA28, significantly associated (p = 0.0005) to IgA levels in Shar-Pei, was positioned within the first intron of the gene SLIT1. Both KIRREL3 and SLIT1 are highly expressed in the central nervous system and in bone marrow and are potentially important during B-cell development. SERPINA9 expression is restricted to B-cells and peaks at the time-point when B-cells proliferate into antibody-producing plasma cells. The suggestively associated regions were enriched for genes in Gene Ontology gene sets involving inflammation and early immune cell development.  相似文献   

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The acknowledged success of early Homo has generally been thought to reflect male-dominated provisioning and associated patterns of co-operative social organization; recently, however, such conclusions have been challenged with the argument that post-menopausal females, instead, played a significant role in early human subsistence activities; males, it has been proposed, had a very minor role in food acquisition in early Homo . The fossil record, however, indicates minimal old-age survivorship of either sex and heavy young adult mortality, a pattern which is also seen in larger prehistoric and ethnographic samples. Heavy young adult mortality, when combined with characteristically slow maturation, represents a paradox which humans have solved through new reproductive strategies (early weaning and alloparenting) and new life history stages (childhood and adolescence). Stone tools, when used to acquire marrow and brain tissue to feed needful youngsters, may also have been among the strategies developed in response to frequent early parental death.  相似文献   

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