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121.
Overall progress in life expectancy (LE) depends increasingly on survival in older ages. The birth cohorts now reaching old age have experienced considerable educational expansion, which is a driving force for the social change and social inequality. Thus, this study examines changes in old age LE by educational attainment in the Nordic countries and aims to find out to what extent the change in national LEs is attributable to education-specific mortality and the shifting educational composition. We used national register data comprising total 65 + populations in Denmark, Finland, Norway and Sweden to create period life tables stratified by five-year age groups (65–90 +), sex and educational attainment. Difference in LE between 2001 and 2015 was decomposed into the contributions of mortality changes within each educational group and changes in educational composition. Increasing LE at all ages and in all educational groups coincided with persistent and growing educational inequalities in all countries. Most of the gains in LE at age 65 could be attributed to decreased mortality (63–90%), especially among those with low education, the largest educational group in most countries. The proportion of the increase in LE attributable to improved education was 10–37%, with the highest contributions recorded for women in Norway and Sweden. The rising educational levels in the Nordic countries still carry potential for further gains in national LEs. However, the educational expansion has contributed to uneven gains in LE between education groups, which poses a risk for the future increase of inequalities in LE.Supplementary InformationThe online version contains supplementary material available at 10.1007/s10433-022-00698-y.  相似文献   
122.
Receptor-activity-modifying proteins (RAMPs) are ubiquitously expressed membrane proteins that associate with different G protein–coupled receptors (GPCRs), including the parathyroid hormone 1 receptor (PTH1R), a class B GPCR and an important modulator of mineral ion homeostasis and bone metabolism. However, it is unknown whether and how RAMP proteins may affect PTH1R function. Using different optical biosensors to measure the activation of PTH1R and its downstream signaling, we describe here that RAMP2 acts as a specific allosteric modulator of PTH1R, shifting PTH1R to a unique preactivated state that permits faster activation in a ligand-specific manner. Moreover, RAMP2 modulates PTH1R downstream signaling in an agonist-dependent manner, most notably increasing the PTH-mediated Gi3 signaling sensitivity. Additionally, RAMP2 increases both PTH- and PTHrP-triggered β-arrestin2 recruitment to PTH1R. Employing homology modeling, we describe the putative structural molecular basis underlying our functional findings. These data uncover a critical role of RAMPs in the activation and signaling of a GPCR that may provide a new venue for highly specific modulation of GPCR function and advanced drug design.

G protein–coupled receptors(GPCRs) represent the largest class of membrane-bound proteins and are involved in a multitude of biological processes (1). They are characterized by a seven-transmembrane helix structure, which undergoes a characteristic rearrangement upon binding of agonists. Agonist binding to its cognate receptor induces conformational changes in the transmembrane helices, which are transmitted to the cytosolic face of the receptors and ultimately result in receptor activation, which represents the key step of signal transduction. The combination of crystallographic and cryogenic electron microscopy studies and the employment of optical biosensors to study the reorganization of the seven transmembrane domains has allowed a detailed understanding of the general mechanisms of GPCR activation (25).Earlier structural studies suggest that GPCRs undergo similar conformational changes upon activation, including, most prominently, an outward movement of the transmembrane helix 6 at the cytosolic face, thereby creating a pocket to which the G protein α-subunit can couple (5). More recent studies, however, have revealed that the exact type of changes may depend on the receptor class and the specific receptor (68). Class- and receptor-specific differences may also exist in the interaction of receptors not only with downstream G proteins and β-arrestins but also with accessory and modulatory proteins (9).Studies of the kinetic steps that govern the structural rearrangements which underlie receptor activation (10) showed that its speed might depend on the receptor class and the specific receptor. For example, when exposed to saturating agonist concentrations, most class A GPCRs switch into the active state within tens of milliseconds. The same process takes 1 to 2 ms for a class C GPCR and may take up to a second for class B receptors (1115). Little is known whether the activation kinetics of GPCRs can be modulated by their cellular context and whether proteins other than the receptors themselves might play a role in shaping signaling kinetics and specificity.Here, we study the parathyroid hormone 1 receptor (PTH1R), a prototypical member of class B GPCRs characterized by a large N-terminal domain that binds a major part of their cognate peptide agonists (16, 17). Compared to class A GPCRs, PTH1R activation is relatively slow and occurs in a two-step process: The initial N-terminal binding step has a time constant of ∼140 ms, followed by an interaction of the ligand with the transmembrane core, which changes into its active conformation with a time constant of ∼1 s (11, 14). Pleiotropic in its downstream coupling, PTH1R signals primarily via Gs but can also couple to Gq (18), G12/13 (19), and Gi (20) and interacts with and signals via β-arrestins (21, 22). The two endogenous agonists, parathyroid hormone (PTH) and parathyroid hormone-related peptide (PTHrP), trigger PTH1R activation with similar kinetics and specificity for the various intracellular pathways (2325). However, PTH can induce prolonged signaling from intracellular sites, while PTHrP signals exclusively from the cell surface (26).PTH1R has been reported to interact with modulatory proteins of the receptor-activity-modifying protein (RAMP) family (2729). RAMPs constitute a family of single transmembrane helix proteins with three members: RAMP1, RAMP2, and RAMP3.It is controversial whether PTH1R interacts only or preferentially with RAMP2 (28) or all three RAMPs (28, 29). In RAMP2 knock-out mice, PTH1R function is deregulated, and placental dysfunction is observed (30), suggesting a major physiological role of the PTH1R/RAMP2 interaction. Yet, the molecular mechanisms of how RAMPs may modulate the activation dynamics of PTH1R and their signaling properties remain to be elucidated.To address these questions, we develop and employ biosensors for PTH1R activation and investigate an array of downstream signaling pathways to assess the effects of RAMPs on the activation dynamics and signaling properties of PTH1R in response to its two endogenous ligands, PTH and PTHrP. We observe that RAMP2 specifically interacts with PTH1R and modulates its activation kinetics as well as signaling dynamics in an agonist-dependent manner.  相似文献   
123.
Introduction: Increasing numbers of pre-lingually profoundly deaf adults are seeking a cochlear implant (CI). Pre- and post-operative outcomes are presented on 20 of these patients.

Results: An Adult Pre-Lingually Profoundly Deaf Implant Profile (APDIP) weighted the pre-operative level of concern about potential CI benefit. Results indicated no group mean post-operative open-set improvement. However CUNY sentence testing (auditory plus lip-reading cues) revealed improved performance with a CI. Twelve out of 20 patients used their CIs for more than 10 hours per day, suggesting good usage. Moreover, hours of usage were positively associated with measured benefit on CUNY sentences in the lip-reading plus sound via CI condition. There was no apparent relationship between pre-operative level of concern and post-operative CI performance or hours of processor use.

Conclusion: Results suggest implantation is beneficial and effective in this group.  相似文献   
124.
125.

Background

In Australia and internationally, there is concern about the growing proportion of women giving birth by caesarean section. There is evidence of increased risk of placenta accreta and percreta in subsequent pregnancies as well as decreased fertility; and significant resource implications. Randomised controlled trials (RCTs) of continuity of midwifery care have reported reduced caesareans and other interventions in labour, as well as increased maternal satisfaction, with no statistically significant differences in perinatal morbidity or mortality. RCTs conducted in the UK and in Australia have largely measured the effect of teams of care providers (commonly 6–12 midwives) with very few testing caseload (one-to-one) midwifery care. This study aims to determine whether caseload (one-to-one) midwifery care for women at low risk of medical complications decreases the proportion of women delivering by caesarean section compared with women receiving 'standard' care. This paper presents the trial protocol in detail.

Methods/design

A two-arm RCT design will be used. Women who are identified at low medical risk will be recruited from the antenatal booking clinics of a tertiary women's hospital in Melbourne, Australia. Baseline data will be collected, then women randomised to caseload midwifery or standard low risk care. Women allocated to the caseload intervention will receive antenatal, intrapartum and postpartum care from a designated primary midwife with one or two antenatal visits conducted by a 'back-up' midwife. The midwives will collaborate with obstetricians and other health professionals as necessary. If the woman has an extended labour, or if the primary midwife is unavailable, care will be provided by the back-up midwife. For women allocated to standard care, options include midwifery-led care with varying levels of continuity, junior obstetric care and community based general medical practitioner care. Data will be collected at recruitment (self administered survey) and at 2 and 6 months postpartum by postal survey. Medical/obstetric outcomes will be abstracted from the medical record. The sample size of 2008 was calculated to identify a decrease in caesarean birth from 19 to 14% and detect a range of other significant clinical differences. Comprehensive process and economic evaluations will be conducted.

Trial registration

Australian New Zealand Clinical Trials Registry ACTRN012607000073404.  相似文献   
126.
Soy has been used in traditional medicine for the treatment of various diseases, including cancer. The isoflavones present in soy have been shown in animal models to have cancer-preventing activity. However, the therapeutic effects of isoflavones against cancer are still unclear. We have evaluated the in vitro and in vivo antileukemic activity of genistein (1), a major isoflavone present in soy. We observed that it produced a dose- and time-dependent antineoplastic activity against myeloid and lymphoid leukemic cell lines. In addition, genistein treatment of the leukemic cells reactivated tumor suppressor genes that were silenced by aberrant DNA methylation. A genistein-enriched diet produced a moderate, but significant, antileukemic effect in mice. The limited extent of this in vivo response may have been due to the rapid metabolic inactivation of genistein in mice. Due to the longer half-life of genistein in humans, a soy-enriched diet has the potential to produce plasma levels of this isoflavone in the range of the concentrations used in vitro that produced an antileukemic activity.  相似文献   
127.
OBJECTIVE: To explore women's experiences of nausea and vomiting in pregnancy. DESIGN: secondary (thematic) analysis of data collected by narrative interviews for two wider studies about antenatal screening and about pregnancy for the DIPEx website (www.dipex.org). PARTICIPANTS AND SETTING: A maximum variation sample was recruited throughout the UK. Data from the 73 women interviewed have been analysed. Interviews took place between October 2003 and December 2004, mostly in the home. FINDINGS: sickness is considered a typical and almost inevitable feature of pregnancy. Against this backdrop, a new framework for understanding women's responses to nausea and vomiting in pregnancy, and the meanings they attach to it, is suggested: nausea and vomiting as something to be expected, survived, resisted, resented, and acknowledged by others. KEY CONCLUSIONS: The concepts of loss of self and biographical disruption from the field of chronic illness seem to resonate with the women's experiences, and may perhaps be extended to transient as well as chronic health conditions. People's experiences of their bodies in health as well as illness need to be more widely studied. IMPLICATIONS FOR PRACTICE: Many women would appreciate greater acknowledgement of the distress nausea and vomiting in pregnancy causes them, information about remedies and strategies other women have found helpful, and reassurance. Expressions of empathy by health-care professionals are frequently lacking and particularly desired.  相似文献   
128.
In Britain, teenage pregnancy is seen as both a cause and a consequence of social exclusion. The emphasis on 'prevention' of teenage pregnancy and a limited conception of 'support' within the Teenage Pregnancy Strategy (Social Exclusion Unit, 1999) positions parenthood for young people as a negative choice; this dominant discourse is likely to influence young people's reproductive decisions and experiences. With this in mind, this article focuses on a key finding from a multidisciplinary empirical research study, conducted in a city in the West Midlands of England, which considered and explored young people's experience of support before and following termination and miscarriage. Data were collected via in-depth interviews with professionals and practitioners (n = 15), young mothers (n = 4) and one young father. Although termination and miscarriage are generally perceived as distinct and different issues, the data suggest that the issues become more blurred where younger women are concerned. The experiences of young, 'inappropriately pregnant teenagers' often remain unacknowledged and devalued. This analysis highlights the social and political context in which young women experience termination and miscarriage, and suggests that termination and miscarriage should be acknowledged as significant medical, social and emotional events in the lives of young people.  相似文献   
129.
Primary hypertrophic osteoarthropathy is a condition characterized by clubbing, arthropathy and periostosis of long tubular bones. Three variants of primary hypertrophic osteoarthropathy are distinguished: pachydermoperiostosis, which shows as additional symptom pachydermia; cranio-osteoarthropathy, which has a decreased neurocranium ossification as additional feature; and a secondary form. Primary hypertrophic osteoarthropathy is also genetically heterogeneous, with evidence for both autosomal dominant and autosomal recessive inheritance. We describe two sibs with cranio-osteoarthropathy and briefly review previously reported cases. The present cases demonstrate the phenotypic variability of the condition. The consanguinity in the present family and analysis of previously described cases support autosomal recessive inheritance for cranio-osteoarthropathy.  相似文献   
130.
A total of 134 controlled natural IVF (nIVF) cycles were reviewed retrospectively and compared with 370 stimulated IVF (sIVF) cycles. The clinical pregnancy rate per embryo transfer following nIVF was 27% and 47% in sIVF cycles for patients aged less than 35. However, natural cycle patients could attempt consecutive cycles with much less impact on their lives, both medically and financially. In patients under 35 years of age, the choice of controlled nIVF reduces the cost and risk to the patient, permitting her to have multiple, consecutive attempts, and cumulatively offers a clinical pregnancy rate which approaches that of sIVF. The multiple pregnancy rate in nIVF is significantly reduced compared with sIVF treatment cycles. In patients over 35 years of age the benefits of nIVF were much less evident (clinical pregnancy rate: 8% per embryo transfer) and the opportunity to transfer multiple embryos in these patients seems to be advantageous.  相似文献   
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