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231.
Geographic variation in stroke rates is well established in the general population, with higher rates in the South than in other areas of the United States. ESRD is a potent risk factor for stroke, but whether regional variations in stroke risk exist among dialysis patients is unknown. Medicare claims from 2000 to 2005 were used to ascertain ischemic stroke events in a large cohort of 265,685 incident dialysis patients. A Poisson generalized linear mixed model was generated to determine factors associated with stroke and to ascertain state-by-state geographic variability in stroke rates by generating observed-to-expected (O/E) adjusted rate ratios for stroke. Older age, female sex, African American race and Hispanic ethnicity, unemployed status, diabetes, hypertension, history of stroke, and permanent atrial fibrillation were positively associated with ischemic stroke, whereas body mass index >30 kg/m2 was inversely associated with stroke (P<0.001 for each). After full multivariable adjustment, the three states with O/E rate ratios >1.0 were all in the South: North Carolina, Mississippi, and Oklahoma. Regional efforts to increase primary prevention in the “stroke belt” or to better educate dialysis patients on the signs of stroke so that they may promptly seek care may improve stroke care and outcomes in dialysis patients.Stroke is a catastrophic health event and a leading cause of disability. It represents a particularly heavy burden for the long-term dialysis population, in whom stroke rates are substantially higher than in the general population.1 In the general population, there is substantial geographic variability in stroke rates, with the southeastern United States having long been recognized as a “stroke belt” of higher stroke mortality rates.24 However, whether a stroke belt of increased ischemic stroke incidence exists in dialysis patients has not been formally studied.Although one might suspect that the same factors contributing to ischemic stroke risk in the general population also apply to dialysis patients, there are several reasons to posit that this might not be the case. First, unlike the general population, dialysis patients across the United States have consistent access to insurance and frequent contact with health care providers, who routinely measure their BP, irrespective of geographic location. Second, the nature of vascular disease differs between dialysis and nondialysis patients, so different pathophysiologic mechanisms may be operative in the two populations.5 Third, dialysis patients fundamentally represent a “survivor cohort” relative to individuals with (predialysis) CKD and its attendant cardiovascular disorders, suggesting that epidemiologic trends evident in one population might not be found in the other.6 Accordingly, it is uncertain whether there is substantial geographic variation in stroke risk among dialysis patients and what factors might, in part, explain such a finding.To address this gap in knowledge, we constructed a large cohort of incident dialysis patients to determine whether ischemic stroke rates vary by geography and how differences in stroke rates might be explained by patient characteristics. We reasoned that uncovering the existence of geographic variability in the stroke rates of dialysis patients might provide direction for focused health care efforts in regions at elevated risk, such as screening new dialysis patients for symptoms that might be referable to old strokes, lowering the threshold for investigating cerebrovascular disease, or educating dialysis patients on the importance of seeking immediate care for stroke-type symptoms.  相似文献   
232.

Background

Borderline Personality Disorder (BPD) is well-known to be a clinically severe and impairing diagnosis. Research shows that BPD symptoms decrease in severity over time. However, a subset of patients with BPD continue to meet criteria for the disorder in older adulthood. Little is known about this subset. Perception of BPD as a young-person's diagnosis could lead to under recognition in older patients. As such, the objective of the present report is to provide the first direct comparison between older and younger adults with BPD on demographics, clinical presentation, and functional impairment.

Method

Over 3000 psychiatric outpatients were evaluated with semi-structured diagnostic interviews. Forty-six older adults (age 45–68) and 97 younger adults (age 18–25) met criteria for BPD.

Results

Both groups reported high levels of functional impairment and Axis I comorbidity. Older adults were more likely to endorse chronic emptiness, and less likely to endorse impulsivity, self-harm, and affective instability. Older adults also reported fewer substance use disorders, more lifetime hospitalizations and higher social impairment.

Conclusion

Older adults with BPD had a significantly different clinical presentation from younger adults with BPD, including differences in likelihood of endorsing specific BPD criteria, social impairment, and comorbid substance use. It is important to assess less prototypic features of BPD to avoid overlooking borderline personality features in this population.  相似文献   
233.
234.
This paper examines the concept of resilience in the context of children affected by armed conflict. Resilience has been frequently viewed as a unique quality of certain ‘invulnerable’ children. In contrast, this paper argues that a number of protective processes contribute to resilient mental health outcomes in children when considered through the lens of the child's social ecology. While available research has made important contributions to understanding risk factors for negative mental health consequences of war-related violence and loss, the focus on trauma alone has resulted in inadequate attention to factors associated with resilient mental health outcomes. This paper presents key studies in the literature that address the interplay between risk and protective processes in the mental health of war-affected children from an ecological, developmental perspective. It suggests that further research on war-affected children should pay particular attention to coping and meaning making at the individual level; the role of attachment relationships, caregiver health, resources and connection in the family, and social support available in peer and extended social networks. Cultural and community influences such as attitudes towards mental health and healing as well as the meaning given to the experience of war itself are also important aspects of the larger social ecology.  相似文献   
235.
236.
NaCrO2 with high rate-capability is an attractive cathode material for sodium-ion batteries (NIBs). However, the amount of reversibly extractable Na+ ions is restricted by half, which results in relatively low energy density for practical NIB cathodes. Herein, we describe aliovalent-doped O3–Na0.9[Cr0.9Sn0.1]O2 (NCSnO) and O3–Na0.8[Cr0.9Sb0.1]O2 (NCSbO), both of which show high-voltage characteristics that translate to an increase in energy density. In contrast to NaCrO2, NCSnO and NCSbO can be reversibly charged to 3.80 and 3.95 V, respectively, delivering 0.5 Na+ along with Cr3+/4+ redox alone. The reversible chargeability to Na0.4[Cr0.9Sn0.1]O2 and Na0.3[Cr0.9Sb0.1]O2 is not associated with the suppression of Cr6+ formation. Both compounds show concentrations of Cr6+ that are higher than that of Na0.3CrO2, with an absence of O3′ phases. This implies that aliovalent-doping contributes to a suppression of the Cr6+ migration into tetrahedral sites in the interslab space, which reduces the possibility of irreversible comproportionation. NCSnO and NCSbO deliver capacities comparable to that of NaCrO2, but show a higher average discharge voltage (2.94 V for NaCrO2; 3.14 V for NCSnO; 3.21 V for NCSbO), which leads to a noticeable increase in energy densities. The high-voltage characteristics of NCSnO and NCSbO are also validated via density-functional-theory calculations.

In contrast to O3–NaCrO2, O3–Na0.8[Cr0.9Sb0.1]O2 shows reversibility when charged to 3.95 V and high-voltage charge/discharge features, which results in improvement of energy density.  相似文献   
237.
P-glycoprotein (P-gp) is an ATP-dependent efflux pump that has a marked impact on the absorption, distribution, and excretion of therapeutic drugs. As P-gp inhibition can result in drug–drug interactions and altered drug bioavailability, identifying molecular properties that are linked to inhibition is of great interest in drug development. In this study, we combined chemical synthesis, in vitro testing, quantitative structure–activity relationship analysis, and docking studies to investigate the role of hydrogen bond (H-bond) donor/acceptor properties in transporter–ligand interaction. In a previous work, it has been shown that propafenone analogs with a 4-hydroxy-4-piperidine moiety exhibit a generally 10-fold higher P-gp inhibitory activity than expected based on their lipophilicity. Here, we specifically expanded the data set by introducing substituents at position 4 of the 4-phenylpiperidine moiety to assess the importance of H-bond donor/acceptor features in this region. The results suggest that indeed an H-bond acceptor, such as hydroxy and methoxy, increases the affinity by forming a H-bond with Tyr310.  相似文献   
238.
PurposeTo evaluate tumor response to transarterial chemoembolization as well as biologic characteristics of the tumor as predictors of recurrence after transplantation in patients with hepatocellular carcinoma (HCC) who were bridged or down-staged to liver transplantation.Materials and MethodsAn institutional review board-approved, Health Insurance Portability and Accountability Act-compliant, single-institution retrospective analysis was performed on all patients with HCC who were treated with the use of conventional transarterial chemoembolization or transarterial chemoembolization with drug-eluting embolics (DEE) over a 12-year period and who subsequently underwent liver transplantation (n = 142). Treatment response was based on modified Response Evaluation Criteria in Solid Tumors (mRECIST) imaging criteria and then correlated with tumor characteristics and recurrence. Of the 142 patients followed after transplantation, 127 had imaging after transarterial chemoembolization but before transplantation. Imaging response and post-transplantation recurrence were correlated with patient demographics, liver function, and tumor morphology. HCC recurred in 9 patients (mean time from transplantation, 526 days). Recurrence was analyzed with the use of univariate and multivariate statistics. Kaplan-Meier recurrence-free survival curves were calculated based on immediate imaging response before transplantation with the use of the log-rank test.ResultsBefore transplantation, 57% of patients (72/127) demonstrated complete response (CR) and 24% (31/127) showed partial response (PR). Complete pathologic necrosis occurred in 54% (39/72) of CR patients and 20% (6/31) of PR patients. Poor treatment response, defined as stable disease (SD) or progressive disease (PD), occurred in 18% of patients (24/127) before transplantation and was present in 67% of cases of recurrence (6/9; P < .001). Post-transplantation recurrence was present in 1.4% of patients (1/71) with CR and in 6.5% of patients (2/31) with PR. In patients with SD after transarterial chemoembolization, HCC recurred in 18.8% of transplant patients (3/16) and in 43% of patients (3/7) with PD. Larger pretreatment tumor size (P = .05), higher Child-Pugh score (P = .002), higher tumor grade at explantation (P = .04), and lymphovascular invasion at explantation (P = .008) also were associated with increased incidence of post-transplantation recurrence.ConclusionsPoor tumor response to transarterial chemoembolization before transplantation identifies patients at increased risk for post-transplantation recurrence.  相似文献   
239.
Psychiatric Quarterly - This study investigated whether with disruptions in care due to the COVID-19 pandemic, persons who self-identified as living with a mental health condition increased their...  相似文献   
240.
Journal of Neurology - Parkinson’s disease (PD) is a progressive neurodegenerative disorder. Genetic modifiers, environmental factors and gene–environment interactions have been found...  相似文献   
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