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991.
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993.
Objectives: Depression is a common health problem in elderly nursing home (NH) residents and is often under-recognized and under-treated. This study aimed to determine the prevalence rates of depression and identify the risk factors associated with depression in the elderly NH population in Singapore.

Methods: A sample of 375 residents in six NHs in Singapore, aged 55 years and above, was assessed with the Structural Clinical Interview (SCID), based on the Diagnostic and Statistical Manual of Mental Disorders, fourth edition (DSM-IV) criteria. The association of demographic, functional and health-related characteristics with depression was examined using multivariate logistic regression analyses.

Results: Overall point prevalence for depression in the elderly NH residents was found to be 21.1% (95% confidence intervals (CI): 17.1%–25.6%). The prevalence rate for minor depression in the elderly NH residents was 14.4% (95% CI: 11.1%–18.5%) and 6.7% (95% CI: 4.5%–9.8%) for major depression. Significant risk factors that were found to be associated with depression were length of stay for more than 2 years, known history of depression, pain, and no or lack of social contact.

Conclusion: The prevalence rates for depression were high among NH residents in Singapore. More attention is needed to care for the psychosocial needs of elderly NH residents in Singapore.  相似文献   

994.
A majority of case control studies of suicide risks in psychiatric patients reveal an excess of risk factors in cases. None of the case control studies has been conducted blind to case identity. The present study examined the possibility that skilled clinicians could identify suicides blind from case records of last episode of care. Records of 39 suicides of psychiatric patients and their matched controls (N = 78) were abstracted blind and dichotomously rated for suicide by seven raters. Success in identification of cases approximated to chance expectation. Pending replication, these disappointing findings call in question the clinical utility of risk factor findings to date, their validity as a basis for significant change in service provision and the medico-legal significance of records in suicide-related civil law suits.  相似文献   
995.

Background

As important mediators of solute transport at the blood–brain and blood–cerebrospinal fluid barriers, ATP-binding cassette (ABC) transporters (including ABCB1, ABCC1, and ABCC2), impact the bioavailability of drugs and endogenous substrates in the brain. While several ABCB1, ABCC1, and ABCC2 single nucleotide polymorphisms (SNPs) have been identified, their impact on outcome after traumatic brain injury (TBI) is unknown.

Hypothesis

ABCB1, ABCC1, and ABCC2 SNPs are associated with Glasgow Outcome Scale (GOS) score after TBI.

Methods

DNA samples from 305 adult patients with severe TBI (Glasgow Coma Scale, GCS score ≤ 8) were genotyped for tagging SNPs of ABCB1 (rs1045642; rs1128503), ABCC1 (rs212093; rs35621; rs4148382), and ABCC2 (rs2273697). For each SNP, patients were dichotomized based on presence of variant allele for multivariate analysis to determine associations with GOS assigned at 6 months adjusting for GCS, Injury Severity score, age, and patient sex.

Results

For ABCB1 rs1045642, patients homozygous for the T allele were less likely to be assigned poor outcome versus those possessing the C allele [CT/CC; odds of unfavorable GOS = 0.71(0.55–0.92)]. For ABCC1 rs4148382, patients homozygous for the G allele were less likely to be assigned poor outcome versus those possessing the A allele [AG/AA; odds of unfavorable GOS = 0.73(0.55–0.98)].

Conclusions

In this single-center study, patients homozygous for the T allele of ABCB1 rs1045642 or the G allele of ABCC1 rs4148382 were found to have better outcome after severe TBI. Further study is necessary to replicate these very preliminary findings and to determine whether these associations are due to central nervous system bioavailability of ABC transporter drug substrates commonly used in the management of TBI, brain efflux of endogenous solutes, or both.  相似文献   
996.

Background

Altered cerebral vasomotor reactivity leading to vasospasm can be seen both in patients with primary headache disorders (PHD) and in patients with subarachnoid hemorrhage (SAH). The pathogenesis of vasospasm in post-SAH patients and in headache disorder sufferers may be related. To address this hypothesis, we analyzed a large cohort of SAH patients to determine whether a diagnosis of PHD predisposes to vasospasm, delayed cerebral ischemia, or worsened clinical outcome.

Methods

Prospectively collected data from patients enrolled in the SAH Outcomes Project between 1996 and 2006 were analyzed. Patients were segregated based on whether they had a diagnosis of PHD or not and were subsequently compared for differences in clinical and radiographic outcome.

Results

A total of 921 SAH patients were analyzed, 265 of which had a diagnosis of PHD. In total, symptomatic vasospasm was seen in 17 %, while angiographic vasospasm was seen in 28 %. Vasospasm rates were similar among patients with a PHD and in those without a PHD (p > 0.05). However, on multivariate analysis new ischemic infarcts were more common in patients with a PHD as compared to patients without a PHD (p = 0.015). Functional outcomes at 3 months were similar among PHD and non-PHD patients (p > 0.05).

Conclusion

A history of PHD is associated with an increased rate of ischemic infarcts during admission for SAH. Increased rates of vasospasm within small cerebral blood vessels may be implicated. Further studies are warranted to more closely link the mechanisms of vasospasm in PHD and SAH patients.  相似文献   
997.
Timely and efficient information transfer at synapses is fundamental to brain function. Synapses are highly dynamic structures that exhibit long-lasting activity-dependent alterations to their structure and transmission efficiency, a phenomenon termed synaptic plasticity. These changes, which occur through alterations in presynaptic release or in the trafficking of postsynaptic receptor proteins, underpin the formation and stabilisation of neural circuits during brain development, and encode, process and store information essential for learning, memory and cognition. In recent years, it has emerged that the ubiquitin-like posttranslational modification SUMOylation is an important mediator of several aspects of neuronal and synaptic function. Through orchestrating synapse formation, presynaptic release and the trafficking of postsynaptic receptor proteins during forms of synaptic plasticity such as long-term potentiation, long-term depression and homeostatic scaling, SUMOylation is being increasingly appreciated to play a central role in neurotransmission. In this review, we outline key discoveries in this relatively new field, provide an update on recent progress regarding the targets and consequences of protein SUMOylation in synaptic function and plasticity, and highlight key outstanding questions regarding the roles of protein SUMOylation in the brain.  相似文献   
998.

Background

Increasing pressures on emergency departments (ED) are straining services and creating inefficiencies in service delivery worldwide. A potentially avoidable pressure is inappropriate attendances (IA); typically low urgency, self-referred patients better managed by other services. This study examines demographics and temporal trends associated with IA to help inform measures to address them.

Methods

Using a national ED dataset, a cross-sectional examination of ED attendances in England from April 2011 to March 2012 (n?=?15,056,095) was conducted. IA were defined as patients who were self-referred; were not attending a follow-up; received no investigation and either no treatment or ‘guidance/advice only’; and were discharged with either no follow-up or follow-up with primary care. Small, nationally representative areas were used to assign each attendance to a residential measure of deprivation. Multivariate analysis was used to predict relationships between IA, demographics (age, gender, deprivation) and temporal factors (day, month, hour, bank holiday, Christmas period).

Results

Overall, 11.7% of attendances were categorized as inappropriate. IA peaked in early childhood (adjusted odds ratio (AOR)?=?1.53 for both one and two year olds), and was elevated throughout late-teens and young adulthood, with odds reducing steadily from age 27 (reference category, age 40). Both IA and appropriate attendances (AA) were most frequent in the most deprived populations. However, relative to AA, those living in the least deprived areas had the highest odds of IA (AOR?=?0.89 in most deprived quintile). Odds of IA were also higher for males (AOR?=?0.95 in females). Both AA and IA were highest on Mondays, whilst weekends, bank holidays and the period between 8 am and 4 pm saw more IA relative to AA.

Conclusions

Prevention of IA would be best targeted at parents of young children and at older youths/young adults, and during weekends and bank holidays. Service provision focusing on access to primary care and EDs serving the most deprived communities would have the most benefit. Improvements in coverage and data quality of the national ED dataset, and the addition of an appropriateness field, would make this dataset an effective monitoring tool to evaluate interventions addressing this issue.
  相似文献   
999.
Activity-regulated cytoskeleton-associated protein (Arc) integrates information from multiple intracellular signaling cascades and, in turn, regulates cytoskeletal proteins involved in structural synaptic modifications. The purposes of the present study were: (1) to determine if the retrieval of contextual memories would induce Arc in hippocampal and amygdalar neurons; (2) use unbiased stereology at the ultrastructural level to quantify synapses contacting Arc-labeled (Arc+) and unlabeled (Arc?) postsynaptic structures in brain regions in which the amount of Arc integrated density (ID) correlated strongly with the degree of amphetamine conditioned place preference (AMPH CPP). The retrieval of contextual memories increased the Arc ID in the dentate gyrus, cornu ammonis (CA)1, and CA3 fields of the hippocampus and the basolateral, lateral, and central nuclei of the amygdala but not the primary auditory cortex, a control region. Stereological quantification of Arc+ and Arc? synapses in the basolateral nucleus of the amygdala (BLA) was undertaken because the strongest relationship between the amount of Arc ID and AMPH CPP was observed in the BLA. The retrieval of contextual memories increased the number and density of asymmetric (presumed excitatory) synapses contacting Arc+ spines and dendrites of BLA neurons, symmetric (presumed inhibitory or modulatory) synapses contacting Arc+ dendrites of BLA neurons, and multisynaptic boutons contacting Arc+ postsynaptic structures. Thus, the retrieval of contextual memories increases Arc in the amygdala and hippocampus, an effect that could be important for approach behavior to a drug-associated context.  相似文献   
1000.
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