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11.
Screening asymptomatic women in the general population for 'early ovarian ageing' will be more effective in high-risk groups. Recent findings support the hypothesis that women with polycystic ovaries (PCO) may have actually been born with a larger pool of resting follicles. The mechanism is almost certainly genetic and occurs in fetal life. If, as is widely accepted, the rate of depletion of the ovarian reserve depends primarily on the size of the remaining pool of small follicles, women with PCO will be unlikely to undergo an accelerated depletion of their follicle pool, normally seen in the late thirties, significantly earlier. In terms of asymptomatic screening for early ovarian ageing in the general population, women with PCO constitute a low-risk group and should therefore be excluded. 相似文献
12.
Nichols SM Bavister BD Brenner CA Didier PJ Harrison RM Kubisch HM 《Human reproduction (Oxford, England)》2005,20(1):79-83
BACKGROUND: A decline in fertility is evident in human females past their middle thirties. This 'reproductive senescence', marked by a sharp decline in pregnancy rates, may be attributed to reductions in numbers of available oocytes and their quality. Because Old World primates exhibit ovarian morphology and physiological control and timing of menstrual cycles closely resembling those of humans, the current study investigated the rhesus macaque as a potential model for human reproductive senescence. METHODS: Ovaries collected from females aged 1-25 years and divided into five age groups were analysed histologically. RESULTS: General ovarian morphology demonstrated significant changes as the females approached menopause. The proportions of primordial and primary follicles all demonstrated significant differences across age groups (primordial: 77.1, 79.9, 69.7, 62.9, 55.1%; primary: 21.5, 18.8, 28.5, 35.2, 43.1% for age groups 1 to 5 respectively; P<0.0001 for both). Samples from females approaching or undergoing the menopausal transition (aged 20-25 years) demonstrated evidence of ovarian senescence, having scattered and atretic follicles, low numbers of primordial follicles and reduced stromal tissue. CONCLUSION: This study supports the value of the rhesus monkey as a model for reproductive ageing because its ovary undergoes follicular reservoir depletion similar to that seen in humans. 相似文献
13.
Fertilization and early embryology: Influence of maternal age on meiotic spindle assembly oocytes from naturally cycling women 总被引:1,自引:0,他引:1
Battaglia D.E.; Goodwin P.; Klein N.A.; Soules M.R. 《Human reproduction (Oxford, England)》1996,11(10):2217-2222
To examine the effects of maternal ageing on the meiotic apparatus,we obtained oocytes from naturally cyding women in two age groups,including younger (aged 2025 years) and older (aged 4045years) women. Using high- resolution confocal microscopy weobtained a detailed picture of the meiotic spindle and chromosomeplacement during various phases of meiosls. Our data revealedthat the meiotic spindle in older women is frequently abnormal,both with regard to chromosome alignment and the micro- tubulematrix that comprise the meiotic spindle. The spindle in 79%of the oocytes from the older group exhibited abnormal tubulinplacement and one or more chromosomes were displaced from themetaphase plate during the second meiotic division. In contrast,only 17% of the oocytes from the younger age group exhibitedaneuploid conditions. The majority of eggs from this group possesseda well ordered, meiotlc spindle containing chromosomes thatwere fully aligned within a distinct metaphase plate in thespindle. Chromosome management during meiosis is directed bymicrotubule assembly within the spindle. These data suggestthat the regulatory mechanisms responsible for assembly of themeiotic spindle are significantly altered in older women, leadingto the high prevalence of aneuploidy. 相似文献
14.
The effect of ageing in spinal cord injured humans on the blood pressure and heart rate responses during fatiguing isometric exercise 总被引:3,自引:0,他引:3
Groups of 50 healthy male controls and 50 subjects suffering from paraplegia (aged 20–65 years) were examined as to the inter-relationships
between age, paraplegia and the strength, endurance, blood pressure and heart rate responses to fatiguing isometric exercise.
Contractions were maintained in both groups under voluntary effort and through a contraction induced by electrical stimulation
in the paraplegic group. All contractions were maintained to fatigue at a tension of 40% of the maximal muscle strength in
either the handgrip or quadriceps muscles. Muscle strength of the handgrip was higher in the paraplegic subjects than in the
controls, averaging 589 N and 463 N, respectively for the two groups. In contrast, quadriceps leg extension strength averaged
696 N in the controls and 190 N in the paraplegic groups; for both groups, ageing was associated with a reduction in muscle
strength. While leg endurance was less in the paraplegic group than the control group, handgrip endurance was similar in the
two groups, endurance increasing with ageing in both the controls and paraplegics. Both systolic and diastolic blood pressures
increased at rest in paraplegic and control subjects with age. The magnitude of the pressor response to exercise also increased
with age. This was true during both voluntary exercise and exercise induced through electrical stimulation in the paraplegic
groups. The heart rate response (change in heart rate during exercise) to a fatiguing isometric handgrip contraction decreased
by about 50% between the ages of 20 and 60 years in both the controls and paraplegics for isometric handgrip exercise. In
contrast, heart rate changed little with age during contractions of the quadriceps muscle in paraplegics which were induced
by electrical stimulation.
Electronic Publication 相似文献
15.
Tanvir S Sian Ushnah S. U. Din Colleen S. Deane Ken Smith Amanda Gates Jonathan N. Lund John P. Williams Ricardo Rueda Suzette L. Pereira Bethan E. Phillips Philip J. Atherton 《Nutrients》2021,13(5)
Ageing is associated with postprandial muscle vascular and metabolic dysfunction, suggesting vascular modifying interventions may be of benefit. Reflecting this, we investigated the impact of acute cocoa flavanol (450–500 mg) intake (versus placebo control) on vascular (via ultrasound) and glucose/insulin metabolic responses (via arterialised/venous blood samples and ELISA) to an oral nutritional supplement (ONS) in twelve healthy older adults (50% male, 72 ± 4 years), in a crossover design study. The cocoa condition displayed significant increases in m. vastus lateralis microvascular blood volume (MBV) in response to feeding at 180 and 240-min after ONS consumption (baseline: 1.00 vs. 180 min: 1.09 ± 0.03, p = 0.05; 240 min: 1.13 ± 0.04, p = 0.002), with MBV at these timepoints significantly higher than in the control condition (p < 0.05). In addition, there was a trend (p = 0.058) for MBV in m. tibialis anterior to increase in response to ONS in the cocoa condition only. Leg blood flow and vascular conductance increased, and vascular resistance decreased in response to ONS (p < 0.05), but these responses were not different between conditions (p > 0.05). Similarly, glucose uptake and insulin increased in response to ONS (p < 0.05) comparably between conditions (p > 0.05). Thus, acute cocoa flavanol supplementation can potentiate oral feeding-induced increases in MBV in older adults, but this improvement does not relay to muscle glucose uptake. 相似文献
16.
《Vaccine》2021,39(26):3520-3527
Influenza, pneumococcal disease, and shingles (herpes zoster) are more prevalent in older people. These illnesses are preventable via vaccination, but uptake is low and decreasing. Little research has focused on understanding the psychosocial reasons behind older adults’ hesitancy towards different vaccines. A cross-sectional survey with 372 UK-based adults aged 65–92 years (M = 70.5) assessed awareness and uptake of the influenza, pneumococcal, and shingles vaccines. Participants provided health and socio-demographic data and completed two scales measuring the psychosocial factors associated with vaccination behaviour. Self-reported daily functioning, cognitive difficulties, and social support were also assessed. Participants were additionally given the opportunity to provide free text responses outlining up to three main reasons for their vaccination decisions. We found that considerably more participants had received the influenza vaccine in the last 12 months (83.6%), relative to having ever received the pneumococcal (60.2%) and shingles vaccines (58.9%). Participants were more aware of their eligibility for the influenza vaccine, and were more likely to have been offered it. Multivariate logistic regression analyses showed that a lower sense of collective responsibility independently predicted lack of uptake of all three vaccines. Greater calculation of disease and vaccination risk, and preference for natural immunity, also predicted not getting the influenza vaccine. For both the pneumococcal and shingles vaccines, concerns about profiteering further predicted lack of uptake. Analysis of the qualitative responses highlighted that participants vaccinated to protect their own health and that of others. Our findings suggest that interventions targeted towards older adults would benefit from being vaccine-specific and that they should emphasise disease risks and vaccine benefits for the individual, as well as the benefits of vaccination for the wider community. These findings can help inform intervention development aimed at increasing vaccination uptake in future. 相似文献
17.
Way K. Bong PhD Lisa M. Gaustadnes Master Astrid Bergland PhD Weiqin Chen PhD Asta Bye Phd Clinical Dietitian 《Health & social care in the community》2021,29(6):1695-1705
The aim of this study is to investigate how community-living older people interpret the Norwegian version of Older People's Quality of Life (OPQOL) questionnaire. The original OPQOL questionnaire was translated based on guidelines for cross-cultural translation. The Three-Step Test-Interview instrument was adopted to investigate how community-living older people interpreted the questionnaire. Data were collected from 14 participants (72–89 years). The questionnaire was filled in under observation. Semi-structured interviews were then conducted to clarify the observational data and elicit the participants’ experiences and opinions. Lastly, data were analysed using a hermeneutic interpretation approach. Our findings indicate that most of the participants managed to complete the OPQOL questionnaire without problems. The data analysis resulted in four primary themes: relevance & applicability, formulation, consistency & accuracy and subjectivity. The questionnaire covered all aspects related to the participants’ quality of life. However, statements related to religion were found to be irrelevant to their quality of life. Most of the participants thought that religion, philosophy and culture should be separate rather than included in the same statement. The participants missed the option of ‘not applicable’ when the statements were irrelevant to them. The statements are formulated in both positive and negative ways, which was sometimes confusing to them. The participants perceived phases such as “around me” “local,” and “things” as ambiguous, and thus they raised concerns about whether the OPQOL questionnaire could capture consistent data regarding their quality of life. The results of this study pinpoint the issues that community-living older people faced when interpreting and answering the Norwegian version of OPQOL questionnaire. These issues were mostly caused by sociocultural differences. Our work provides an overview of the changes that must be made in the questionnaire in order to address these sociocultural differences while using the OPQOL questionnaire in the Norwegian context. 相似文献
18.
Catherine Lunt Christopher Dowrick Mari Lloyd-Williams 《Health & social care in the community》2021,29(5):1201-1221
There is a lack of robust evidence regarding outcomes for day care use among older people living with long-term conditions (LTCs). Day care is provided by independent, private and voluntary and charitable sectors. This systematic review aims to establish current evidence of outcomes for older people with LTCs attending day care services and outcomes on carers, across all service models. Narrative synthesis of quantitative and qualitative data was undertaken. The review adhered to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. A systematic literature search was carried out across eight electronic databases and reference lists of key journals between 2004 and October 2020 were searched. Searches returned 1,202 unique titles. Forty-five articles from 16 countries met the criteria on review of title, abstract and full article. There is limited evidence suggesting improved levels of perceived psychological health, quality of life, perceived general health, physical health and functioning for older people attending day care who have LTCs. The respite function of day care resulted in positive outcomes for carers. Studies evaluating outcomes for participants or carers were limited in quantity and quality. There is limited information regarding outcomes for day care attendance for older people with multiple LTCs from existing literature. Further research focusing on LTCs and day care attendance would benefit this field. 相似文献
19.
beta-amyloid deposition and neurofibrillary tangle formation in the olfactory bulb in ageing and Alzheimer's disease 总被引:1,自引:0,他引:1
Impaired olfaction, hyposmia or anosmia are part of the clinical phenotype in neurodegenerative disorders including Alzheimer's disease (AD). It has been proposed that the most severely affected areas are interconnected with the central olfactory system in contrast to the relative sparing of other sensory areas which lack olfactory connections. The pathology of the first synaptic relay in the olfactory pathway, the olfactory bulb (OB), has been studied in AD, but the results have been inconsistent. In order to define more fully the pathology of the OB, we analysed 15 AD and 15 control cases, using amyloid and tau immunohistochemistry on serial sections. This study demonstrates for the first time that all layers of the OB are severely affected in AD and in normal ageing. The principal effector cells of the OB, the mitral cells, developed neurofibrillary tangles (NFTs) both in AD and in controls. All the cases, with the exception of two of the controls, contained NFTs. Amyloid immunoreactivity was detected in diffuse, primitive, classical and compact deposits in AD, while five control cases contained mainly diffuse deposits. We did not find a correlation between amyloid deposition and NFT formation. Among the control cases, two contained neither amyloid nor NFTs, eight had NFTs but no amyloid and only five had both NFTs and amyloid. All the AD cases had NFT and amyloid deposition. Our data suggest that the earlier pathology in the OB is NFT formation and more than ten NFTs/section is compatible with 93.3% diagnostic accuracy for AD. 相似文献
20.
In the human hypothalamus, arginine-vasopressin (AVP) is produced for a major part by the neurones of the supraoptic nucleus (SON). Since plasma AVP levels in men were reported to be higher than those of women and we did not find a sex difference in the neurone number, a higher vasopressinergic neurone activity was supposed to be present in the SON of men. Therefore we studied the size of the Golgi-apparatus (GA), which has been demonstrated previously to be a sensitive parameter for protein synthetic ability of neurones, in 15 men and 17 women ranging in age from 29 to 94 years. A polyclonal antibody against immunoaffinity purified MG-160, a sialoglycoprotein of the medial cisternae of the GA was applied on paraffin-embedded sections containing the dorsolateral SON (dl-SON) from which 90-95% of neurones are vasopressinergic. SON areas that contain oxytocin (OT) cells were excluded on the basis of adjacent sections stained with a monoclonal antibody against OT. By means of an image analysis system the size of the GA and the cellular profile area were determined in dl-SON neurones with a nucleolus. Our results showed indeed an age-dependent sex difference in the size of the GA that appeared to be twice as large in young men (< or = 50 years old) than in young women of the same age. The size of the GA increased with age in women but not in men. In addition, the mean cell profile area, another measure for neuronal activity, was significantly larger in young men than in young women and was in old women larger than in young women. In conclusion, these data show the presence of a sex-dependent age-difference in the activity of vasopressinergic neurones in dl-SON which may relate to differences in AVP and sex hormone levels and kidney AVP receptors. 相似文献