Blood Pressure in Acute Ischemic Stroke

Hypertension is present in up to 84% of patients presenting with acute stroke, and a smaller proportion of patients have blood pressures that are below typical values in the context of cerebral ischemia. Outcomes are generally worse in those who present with either low or severely elevated blood pressure. Several studies have provided valuable information about malignant trends in blood pressure during the transition from the acute to the subacute phase of stroke. It is not uncommon for practitioners in clinical practice to identify what appear to be pressure-dependent neurologic deficits. Despite physiologic and clinical data suggesting the importance of blood pressure modulation to support cerebral blood flow to ischemic tissue, randomized controlled trials have not yielded robust evidence for this in acute ischemic stroke. We highlight previous studies involving acute-stroke patients that have defined trends in blood pressure and that have evaluated the safety and efficacy of blood-pressure modulation in acute ischemic stroke. This overview reports the current status of this topic from the perspective of a stroke neurologist and provides a framework for future research.

Association of Insurance Status with Stroke-Related Mortality and Long-term Survival after Stroke

BACKGROUND

Lack of insurance is a barrier to optimal stroke risk factor control but data on its long-term impact on stroke outcomes are sparse. We assessed the association between health insurance and long-term mortality after stroke.

METHODS

Using data from the National Health and Nutrition Examination Surveys 1999-2004 with follow-up mortality assessment through 2006, we examined the independent effect of health insurance on (1) stroke mortality among all adult participants (n = 15,049) and (2) vascular and all-cause mortality rates among participants with self-reported stroke (n = 563).

RESULTS

Among individuals without a previous stroke, uninsured individuals aged less than 65 years were more likely to die of stroke than those with insurance (adjusted hazard ratio [HR], 3.13; 95% confidence interval [CI], .96-10.23); however, among those aged 65 years or older, those with private insurance, private plus Medicare, or Medicare plus Medicaid had similar risk of stroke mortality when compared to those with Medicare alone. Stroke survivors aged 65 years or older with private insurance were less likely to die from vascular causes (adjusted HR, .38; 95% CI, .23-.63) compared to those with Medicare alone. For stroke survivors aged less than 65 years, uninsured individuals had similar all-cause mortality rates compared to their counterparts with insurance.

CONCLUSIONS

Insurance status influences risk of dying from a stroke in the general population, as well as long-term mortality rates among stroke survivors in the United States, but these relationships vary by age.

Abstract T P139: Rising Rates of the Metabolic Syndrome Among Stroke Survivors in the United States

BACKGROUND: Metabolic syndrome (MetS), a constellation of cardiometabolic risk factors clustering together, affects >47 million US adults and has been independently linked to primary and recurrent stroke risk. Prevalence and trends in MetS among stroke survivors in the United States are unknown.

OBJECTIVES: To evaluate recent temporal trends in age and sex-specific MetS prevalence among adults with/without stroke in the US.

METHODS: Prevalence of MetS was assessed among fasting adults ≥35 years who participated in National Health and Nutrition Examination Surveys 1999-2010 (n=9,343).

Prevalence estimates were weighted to obtain nationally representative estimates (n=430,371,669). MetS was defined by the 2009 harmonized definition. Stroke was determined by self-report.

RESULTS: In all groups except men 35-64 years, MetS prevalence was similar among adults with and without stroke in 1999-2002 (Table). MetS prevalence rates were flat from 1999 to 2010 among those without stroke, but increased among stroke survivors, such that up to 80% of men and 86% of women with stroke had MetS, with the greatest rise among the middle-aged. Stroke survivors aged 35-64 years were ~3 times more likely to have MetS than their counterparts without stroke (OR 3.24, 95% CI 1.60-6.55 for men and OR 2.55, 95% CI 1.45-4.50 for women).

DISCUSSION: Due to a differential rise in MetS in stroke survivors over the last 10 years, as many as 9 out of 10 stroke survivors now have MetS, suggesting that Mets may increasingly be placing people at risk for stroke. Intensified efforts aimed at identifying and treating MetS, especially among middle-aged individuals, may be warranted to avert stroke risk.

Eastern equine encephalitis in children, Massachusetts and New Hampshire,USA, 1970-2010

We describe the clinical, laboratory, and radiographic characteristics of 15 cases of eastern equine encephalitis in children during 1970-2010. The most common clinical and laboratory features were fever, headache, seizures, peripheral leukocytosis, and cerebrospinal fluid neutrophilic pleocytosis. Radiographic lesions were found in the basal ganglia, thalami, and cerebral cortex. Clinical outcomes included severe neurologic deficits in 5 (33%) patients, death of 4 (27%), full recovery of 4 (27%), and mild neurologic deficits in 2 (13%). We identify an association between a short prodrome and an increased risk for death or for severe disease.

Abstract WMP92: Health Insurance Coverage is Associated with Mortality after Stroke

Background: Management of treatable risk factors is of paramount importance to decrease stroke mortality and improve outcomes after stroke. Optimizing healthcare access serves as a foundation for risk factor management. The association between health insurance type and mortality after stroke warrants investigation.

METHODS: Using data from the National Health and Nutrition Examination Surveys 1999-2004 with follow up mortality assessment through 2006, we examined the relationship between health insurance and (1) stroke mortality among all adult participants (n=15,049) and (2) vascular and all-cause mortality among participants with self-reported stroke (n=563). The relationship between insurance type and the aforementioned outcomes were evaluated using Cox regression after adjusting for covariates (age, sex, race, income, BMI, and major medical comorbidities).

RESULTS: Among 10,786 participants <65 years (representing 163,891,359 individuals in the US) 69% had private insurance, 21% were not insured and 4% had Medicaid. Among 4,263 participants ≥ 65 years (representing 33,375,771 individuals in the US), 43% had Medicare + private insurance, 41% had Medicare only, 8% had private insurance only and 4.2% had Medicare + Medicaid. Stroke survivors ≥65 years with private insurance were less likely to die from vascular causes compared to those with Medicare alone (adjusted HR 0.38, CI 0.23-0.63, p<0.001). The same subjects had lower all-cause mortality if they had Medicare + private insurance compared to Medicare alone (adjusted HR 0.63, CI 0.37-1.08, p=0.07). Uninsured stroke survivors <65 years had similar all-cause mortality to those with insurance (adjusted HR 0.97, CI 0.29-3.23). In the general population, uninsured individuals <65 years were more likely to die of stroke than those with insurance (adjusted HR 3.13, CI 0.96-10.23, p=0.06); however, insurance status did not affect stroke mortality among individuals ≥65 years.

CONCLUSION: In this nationally representative sample of the US population followed for up to 7 years, insurance status appears to have a profound, independent impact on mortality rates after stroke. These findings highlight the importance of health insurance coverage in post-stroke outcomes.

Effect of alveolar epithelial cell plasticity on the regulation of GM-CSF expression

Local pulmonary expression of granulocyte-macrophage colony-stimulating factor (GM-CSF) is critically important for defense of the pulmonary alveolar space. It is required for surfactant homeostasis and pulmonary innate immune responses and is protective against lung injury and aberrant repair. Alveolar epithelial cells (AEC) are a major source of GM-CSF; however, the control of homeostatic expression of GM-CSF is incompletely characterized. Increasing evidence suggests considerable plasticity of expression of AEC phenotypic characteristics. We tested the hypothesis that this plasticity extends to regulation of expression of GM-CSF using 1) MLE-12 cells (a commonly used murine cell line expressing some features of normal type II AEC, 2) primary murine AEC incubated under standard conditions [resulting in rapid spreading and loss of surfactant protein C (SP-C) expression with induction of the putative type I cell marker (T1α)], or 3) primary murine AEC on a hyaluronic acid/collagen matrix in defined medium, resulting in preservation of SP-C expression. AEC in standard cultures constitutively express abundant GM-CSF, with further induction in response to IL-1β but little response to TNF-α. In contrast, primary cells cultured to preserve SP-C expression and MLE-12 cells both express little GM-CSF constitutively, with significant induction in response to TNF-α and limited response to IL-1β. We conclude that constitutive and cytokine-induced expression of GM-CSF by AEC varies in concert with other cellular phenotypic characteristics. These changes may have important implications both for the maintenance of normal pulmonary homeostasis and for the process of repair following lung injury.

Neuropathology of a fatal case of posterior reversible encephalopathy syndrome

The pathology of posterior reversible encephalopathy syndrome (PRES) is undefined, since it is rarely fatal and is biopsied in only exceptional circumstances. We describe rapidly progressive PRES following stem cell transplant for acute lymphoblastic leukemia. After development of altered mental status, this 8-year-old girl had T2 prolongation of the white matter in a posterior-dominant distribution, eventually developing cerebellar edema, hemorrhage, hydrocephalus, and herniation. Despite surgical and medical management, she died 36 hours later. At autopsy, the occipital and cerebellar white matter and focal occipital cortical gray matter showed a spectrum of microvascular changes, including dilated perivascular spaces containing proteinaceous exudates and macrophages, as well as fibrinoid necrosis and acute hemorrhage, in a distribution corresponding to the neuroimaging abnormalities and reminiscent of those seen in patients with acute hypertensive encephalopathy. Of note, similar microvascular changes were not seen in the kidney or other systemic sites. Thus, the findings indicate a brain-specific microvascular compromise as the substrate of PRES, at least in the rare instance of cases progressing to fatal outcome.

Mechanisms of suppression of alveolar epithelial cell GM-CSF expression in the setting of hyperoxic stress

Pulmonary expression of granulocyte/macrophage colony-stimulating factor (GM-CSF) is critically important for normal functional maturation of alveolar macrophages. We found previously that lung GM-CSF is dramatically suppressed in mice exposed to hyperoxia. Alveolar epithelial cells (AEC) are a major source of GM-CSF in the peripheral lung, and in vivo hyperoxia resulted in greatly reduced expression of GM-CSF protein by AEC ex vivo. We now explore the mechanisms responsible for this effect, using primary cultures of murine AEC exposed to hyperoxia in vitro. Exposure of AEC to 80% oxygen/5% CO(2) for 48 h did not induce overt toxicity, but resulted in significantly decreased GM-CSF protein and mRNA expression compared with cells in normoxia. Similar effects were seen when AEC were stressed with serum deprivation, an alternative inducer of oxidative stress. The effects in AEC were opposite those in a murine lung epithelial cell line (MLE-12 cells), in which hyperoxia induced GM-CSF expression. Both hyperoxia and serum deprivation resulted in increased intracellular reactive oxygen species (ROS) in AEC. Hyperoxia and serum deprivation induced significantly accelerated turnover of GM-CSF mRNA. Treatment of AEC with catalase during oxidative stress preserved GM-CSF protein and mRNA and was associated with stabilization of GM-CSF mRNA. We conclude that hyperoxia-induced suppression of AEC GM-CSF expression is a function of ROS-induced destabilization of GM-CSF mRNA. We speculate that AEC oxidative stress results in significantly impaired pulmonary innate immune defense due to effects on local GM-CSF expression in the lung.

Lentivirus production

RNA interference (RNAi) is a system of gene silencing in living cells. In RNAi, genes homologous in sequence to short interfering RNAs (siRNA) are silenced at the post-transcriptional state. Short hairpin RNAs, precursors to siRNA, can be expressed using lentivirus, allowing for RNAi in a variety of cell types. Lentiviruses, such as the Human Immunodeficiency Virus, are capable to infecting both dividing and non-dividing cells. We will describe a procedure which to package lentiviruses. Packaging refers to the preparation of competent virus from DNA vectors. Lentiviral vector production systems are based on a 'split' system, where the natural viral genome has been split into individual helper plasmid constructs. This splitting of the different viral elements into four separate vectors diminishes the risk of creating a replication-capable virus by adventitious recombination of the lentiviral genome. Here, a vector containing the shRNA of interest and three packaging vectors (p-VSVG, pRSV, pMDL) are transiently transfected into human 293 cells. After at least a 48-hour incubation period, the virus containing supernatant is harvested and concentrated. Finally, virus titer is determined by reporter (fluorescent) expression with a flow cytometer.

Extracellular sulfatases, elements of the Wnt signaling pathway, positively regulate growth and tumorigenicity of human pancreatic cancer cells

Background

Heparan sulfate proteoglycans (HSPGs) are control elements in Wnt signaling, which bind extracellularly to Wnt ligands and regulate their ability to interact with signal transduction receptors on the cell surface. Sulf-1 and Sulf-2 are novel extracellular sulfatases that act on internal glucosamine-6-sulfate (6S) modifications within HSPGs and thereby modulate HSPG interactions with various signaling molecules, including Wnt ligands. Emerging evidence indicates the importance of reactivated Wnt signaling in a number of cancers, including pancreatic adenocarcinoma.

Principle Findings

Both Sulf proteins were upregulated in human pancreatic adenocarcinoma tumors and were broadly expressed in human pancreatic adenocarcinoma cell lines. Expression of human extracellular sulfatases Sulf-1 and Sulf-2 enhanced Wnt signaling in a reconstituted system. Three of four pancreatic adenocarcinoma cell lines tested exhibited autocrine Wnt signaling, in that extracellular Wnt ligands were required to initiate downstream Wnt signaling. Exposure of these pancreatic adenocarcinoma cells to a catalytically inactive form of Sulf-2 or siRNA-mediated silencing of endogenous Sulf-2 inhibited both Wnt signaling and cell growth. Sulf-2 silencing in two of these lines resulted in markedly reduced tumorigenesis in immunocompromised mice.

Conclusions/Significance

We have identified the Sulfs as potentiators of autocrine Wnt signaling in pancreatic cancer cells and have demonstrated their contribution to the growth and tumorigenicity of these cells. Since the Sulfs are extracellular enzymes, they would be attractive targets for therapy of pancreatic cancer. Our results run counter to the prevailing view in the literature that the Sulfs are negative regulators of tumorigenesis.

Hippocampal atrophy in the healthy is initially linear and independent of age

Patients with minimal cognitive impairment (MCI) or Alzheimer's disease (AD) have smaller hippocampal volumes (HV) and increased rates of HV loss (rHVL). A 6-year study was conducted to assess rHVL in healthy aging subjects (HC) in which four MRI scans, each 2 years apart, were obtained on 26 HC with a mean age of 58.8 years when entering the study. rHVLs were linear and significantly differed among subjects, even those sharing an identical apoliporotein E genotype, ranging from .027 to .191 cc/year (S.D. = .022 cc/year), and were not affected by age or sex. rHVL, but not HV, at time of subject entry, was found to predict performance on the delayed recall measure of the Selective Reminder Task obtained 6 years after subject entry into study. Although the molecular events underlying rHVL are unclear, the significance of rHVL in subjects in their sixth and seventh decades of life for predicting age-related cognitive trajectories and whether changes in rHVLs foreshadow the development of MCI are the subject of ongoing study.

Duox2 exhibits potent heme peroxidase activity in human respiratory tract epithelium

The dual oxidase isozymes Duox1 and Duox2 exhibit functional NADPH:O(2) oxidoreductase activity in thyroid and respiratory tract cells and are thought to be essential for H(2)O(2) generation in these tissues. However, it is not universally accepted that the heme peroxidase domains of the Duox isozymes are functional. To address this question, we modulated Duox2 expression in human tracheobronchial epithelial (TBE) cell culture systems and quantified peroxidase activity. We discovered that interferon-gamma (IFN-gamma) induced robust peroxidase activity in TBE cells that paralleled Duox2 expression. IFN-gamma-induced peroxidase activity was abolished in the presence of sodium azide, which implicated the activation of a heme peroxidase. IFN-gamma-induced peroxidase activity was abolished in TBE cell lines expressing anti-Duox2 short hairpin RNA transcripts. Together, these data unequivocally demonstrated that Duox2 contains a functional heme peroxidase in intact respiratory tract epithelium.

Cre-lox-regulated conditional RNA interference from transgenes

We have generated two lentiviral vectors for conditional, Cre-lox-regulated, RNA interference. One vector allows for conditional activation, whereas the other permits conditional inactivation of short hairpin RNA (shRNA) expression. The former is based on a strategy in which the mouse U6 promoter has been modified by including a hybrid between a LoxP site and a TATA box. The ability to efficiently control shRNA expression by using these vectors was shown in cell-based experiments by knocking down p53, nucleophosmin and DNA methyltransferase 1. We also demonstrate the usefulness of this approach to achieve conditional, tissue-specific RNA interference in Cre-expressing transgenic mice. Combined with the growing array of Cre expression strategies, these vectors allow spatial and temporal control of shRNA expression in vivo and should facilitate functional genetic analysis in mammals.

Occurrence of spruce bark beetles in forest stands at different levels of air pollution stress

The spruce bark beetle, Ips typographus (L.) is the most serious pest of mature spruce stands, mainly Norway spruce, Picea abies (L.) Karst. throughout Eurasia. A complex of weather-related events and other environmental stresses are reported to predispose spruce stands to bark beetle attack and subsequent tree mortality; however the possible role of industrial pollution as a predisposing factor to attack by this species is poorly understood. The abundance and dynamics of I. typographus populations was evaluated in 60-80 year old Norway spruce stands occurring on 10 x 50 ha sites in five countries within the Carpathian range that were selected in proximity to established ozone measurement sites. Data were recorded on several parameters including the volume of infested trees, captures of adult beetles in pheromone traps, number of attacks, and the presence and relative abundance of associated bark beetle species. In several cases, stands adjacent to sites with higher ozone values were associated with higher bark beetle populations. The volume of sanitary cuttings, a reflection of tree mortality, and the mean daily capture of beetles in pheromone traps were significantly higher at sites where the O(3) level was higher. However, the mean infestation density on trees was higher in plots associated with lower O(3) levels. Captures of beetles in pheromone traps and infestation densities were higher in the zone above 800 m. However, none of the relationships was conclusive, suggesting that spruce bark beetle dynamics are driven by a complex interaction of biotic and abiotic factors and not by a single parameter such as air pollution.

New international long-term ecological research on air pollution effects on the Carpathian Mountain forests, Central Europe

An international cooperative project on distribution of ozone in the Carpathian Mountains, Central Europe was conducted from 1997 to 1999. Results of that project indicated that in large parts of the Carpathian Mountains, concentrations of ozone were elevated and potentially phytotoxic to forest vegetation. That study led to the establishment of new long-term studies on ecological changes in forests and other ecosystems caused by air pollution in the Retezat Mountains, Southern Carpathians, Romania and in the Tatra Mountains, Western Carpathians on the Polish-Slovak border. Both of these important mountain ranges have the status of national parks and are Man & the Biosphere Reserves. In the Retezat Mountains, the primary research objective was to evaluate how air pollution may affect forest health and biodiversity. The main research objective in the Tatra Mountains was to evaluate responses of natural and managed Norway spruce forests to air pollution and other stresses. Ambient concentrations of ozone (O(3)), sulfur dioxide (SO(2)), nitrogen oxides (NO(x)) as well as forest health and biodiversity changes were monitored on densely distributed research sites. Initial monitoring of pollutants indicated low levels of O(3), SO(2), and NO(x) in the Retezat Mountains, while elevated levels of O(3) and high deposition of atmospheric sulfur (S) and nitrogen (N) have characterized the Tatra Mountains. In the Retezat Mountains, air pollution seems to have little effect on forest health; however, there was concern that over a long time, even low levels of pollution may affect biodiversity of this important ecosystem. In contrast, severe decline of Norway spruce has been observed in the Tatra Mountains. Although bark beetle seems to be the immediate cause of that decline, long-term elevated levels of atmospheric N and S depositions and elevated O(3) could predispose trees to insect attacks and other stresses. European and US scientists studied pollution deposition, soil and plant chemistry, O(3)-sensitive plant species, forest insects, and genetic changes in the Retezat and Tatra Mountains. Results of these investigations are presented in a GIS format to allow for a better understanding of the changes and the recommendations for effective management in these two areas.

CP110, a cell cycle-dependent CDK substrate, regulates centrosome duplication in human cells

Centrosome duplication and separation are linked inextricably to certain cell cycle events, in particular activation of cyclin-dependent kinases (CDKs). However, relatively few CDK targets driving these events have been uncovered. Here, we have performed a screen for CDK substrates and have isolated a target, CP110, which is phosphorylated by CDKs in vitro and in vivo. Human CP110 localizes to centrosomes. Its expression is strongly induced at the G1-to-S phase transition, coincident with the initiation of centrosome duplication. RNAi-mediated depletion of CP110 indicates that this protein plays an essential role in centrosome duplication. Long-term disruption of CP110 phosphorylation leads to unscheduled centrosome separation and overt polyploidy. Our data suggest that CP110 is a physiological centrosomal CDK target that promotes centrosome duplication, and its deregulation may contribute to genomic instability.

Whither nursing? Discourses underlying the attribution of master's level performance in nursing

AIM

Drawing upon the selected findings from a multidisciplinary study that sought to explore the meaning of master's level performance in health professional practice, the characteristics which nurse educators attributed to the practice of master's level nursing graduates are analysed to reveal underlying discourses.

BACKGROUND

Although master's level programmes for nurses have been available in the United Kingdom (UK) for the past three decades and current heath policy directives link master's level qualifications with senior clinical nursing roles, the contribution that master's level education might make to the future direction of nursing is unclear.

RESEARCH DESIGN AND METHODS

In-depth interviews were undertaken with a purposive sample of 18 nurse lecturers drawn from eight universities in the UK who were responsible for master's level programmes in nursing. The interview agenda explored participants' perspectives of the characteristics of master's level performance. Drawing upon the methodology of discourse analysis, interview transcripts were interpreted in such a way as to show the implicit discourses underlying the participants' claims regarding their graduate's attributes of professional practice.

FINDINGS

The characteristics attributed to master's graduates were categorized under (a) cognitive competencies, (b) practice-related competencies, (c) research orientation and (d) personal dynamism. However, these attributions are not empirical generalizations, developed inductively. Rather, they draw on socially available discourses regarding the future direction of the profession.

CONCLUSION

The nurse educators drew on the following socially available discourses: (a) a discourse in which nursing is construed as involving great competence in practice, but without radicality of thought. Associated with this is a pervasive rhetoric of pragmatism; (b) a discourse of interprofessional practice in which nursing has a role of leadership. This is associated with a view of the location and power of nursing within the structure of the National Health Service and (c) notably lacking were discourses of care-giving, and of academic/intellectual aspiration. The implications of these discourses for the future direction of nursing are considered.

DYSPHAGIA in Psychiatric Patients

1. Psychiatric patients in acute and long-term care settings may be at high risk for dysphagia and its sequelae. 2. The prevalence of dysphagia in the psychiatric population is higher than commonly believed. 3. Routine screening is essential for the safety and management of psychiatric patients at risk for dysphagia.