Evaluating How Safety-Net Hospitals Are Identified: Systematic Review and Recommendations

Objective:

To systematically review how safety-net hospitals' status is identified and defined, discuss current definitions' limitations, and provide recommendations for a new classification and evaluation framework.

Data Sources:

Safety-net hospital-related studies in the MEDLINE database published before May 16, 2019.

Study Design:

Systematic review of the literature that adheres to Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines.

Data Collection/Extraction Methods:

We followed standard selection protocol, whereby studies went through an abstract review followed by a full-text screening for eligibility. For each included study, we extracted information about the identification method itself, including the operational definition, the dimension(s) of disadvantage reflected, study objective, and how safety-net status was evaluated.

Principal Findings:

Our review identified 132 studies investigating safety-net hospitals. Analysis of identification methodologies revealed substantial heterogeneity in the ways disadvantage is defined, measured, and summarized at the hospital level, despite a 4.5-fold increase in studies investigating safety-net hospitals for the past decade. Definitions often exclusively used low-income proxies captured within existing health system data, rarely incorporated external social risk factor measures, and were commonly separated into distinct safety-net status categories when analyzed.

Conclusions:

Consistency in research and improvement in policy both require a standard definition for identifying safety-net hospitals. Yet no standardized definition of safety-net hospitals is endorsed and existing definitions have key limitations. Moving forward, approaches rooted in health equity theory can provide a more holistic framework for evaluating disadvantage at the hospital level. Furthermore, advancements in precision public health technologies make it easier to incorporate detailed neighborhood-level social determinants of health metrics into multidimensional definitions. Other countries, including the United Kingdom and New Zealand, have used similar methods of identifying social need to determine more accurate assessments of hospital performance and the development of policies and targeted programs for improving outcomes.

Single-arm, open-label, multicentre first in human study to evaluate the safety and performance of dural sealant patch in reducing CSF leakage following elective cranial surgery: the ENCASE trial

OBJECTIVE

The dural sealant patch (DSP) is designed for watertight dural closure after cranial surgery. The goal of this study is to assess, for the first time, safety and performance of the DSP as a means of reducing cerebrospinal fluid (CSF) leakage in patients undergoing elective cranial intradural surgery with a dural closure procedure.

DESIGN

First in human, open-label, single-arm, multicentre study with 360-day (12 months) follow-up.

SETTING

Three large tertiary reference neurosurgical centres, two in the Netherlands and one in Switzerland.

PARTICIPANTS

Forty patients undergoing elective cranial neurosurgical procedures, stratified into 34 supratentorial and six infratentorial trepanations.

INTERVENTION

Each patient received one DSP after cranial surgery and closure of the dura mater with sutures.

OUTCOME MEASURES

Primary composite endpoint was occurrence of one of the following events: postoperative percutaneous CSF leakage, intraoperative leakage at 20 cm H₂O positive end-expiratory pressure or postoperative wound infection. Overall success was defined as achieving the primary endpoint in no more than two patients. Secondary endpoints were device-related serious adverse events or adverse events (AEs), pseudomeningocele and thickness of dura+DSP. Additional endpoints were reoperation in 30 days and user satisfaction.

RESULTS

No patients met the primary endpoint. No device-related (serious) AEs were observed. There were two incidences of self-limiting pseudomeningocele as confirmed on MRI. Thickness of dura and DSP were (mean±SD) 3.5 mm±2.0 at day 7 and 2.1 mm±1.2 at day 90. No patients were reoperated within 30 days. Users reported a satisfactory design and intuitive application.

CONCLUSIONS

DSP, later officially named Liqoseal, is a safe and potentially efficacious device for reducing CSF leakage after intracranial surgery, with favourable clinical handling characteristics. A randomised controlled trial is needed to assess Liqoseal efficacy against the best current practice for reducing postoperative CSF leakage.

TRIAL REGISTRATION NUMBER

NCT03566602.

Associations of Baseline Frailty Status and Age With Outcomes in Patients Undergoing Vestibular Schwannoma Resection

Importance

Although numerous studies have evaluated the influence of advanced age on surgical outcomes following vestibular schwannoma (VS) resection, few if any large-scale investigations have assessed the comparative prognostic effects of age and frailty. As the population continues to age, it is imperative to further evaluate treatment and management strategies for older patients.

Objective

To conduct a population-based evaluation of the independent associations of chronological age and frailty (physiological age) with outcomes following VS resection.

Design, Setting, and Participants

In this large-scale, multicenter, cross-sectional analysis, weighted discharge data from the National Inpatient Sample were searched to identify adult patients (≥18 years old) who underwent VS resection from 2002 through 2017 using International Classification of Diseases, Ninth Revision, Clinical Modification and Tenth Revision, Clinical Modification codes. Data collection and analysis took place September to December 2020.

Main Outcomes and Measures

Complex samples regression models and receiver operating characteristic curve analysis were used to evaluate the independent associations of frailty and age (along with demographic confounders) with complications and discharge disposition. Frailty was evaluated using the previously validated 11-point modified frailty index (mFI).

Results

Among the 27 313 patients identified for VS resection, the mean (SEM) age was 50.4 (0.2) years, 15 031 (55.0%) were women, and 4720 (21.0%) were of non-White race/ethnicity, as determined by the National Inpatient Sample data source. Of the included patients, 15 090 (55.2%) were considered robust (mFI score = 0), 8204 (30.0%) were prefrail (mFI score = 1), 3022 (11.1%) were frail (mFI score = 2), and 996 (3.6%) were severely frail (mFI score ≥3). On univariable analysis, increasing frailty was associated with development of postoperative hemorrhagic or ischemic stroke (odds ratio [OR], 2.44 [95% CI, 2.07-2.87]; area under the curve, 0.73), while increasing age was not. Following multivariable analysis, increasing frailty and non-White race/ethnicity were independently associated with both mortality (adjusted OR [aOR], 2.32 [95% CI, 1.70-3.17], and aOR, 3.05 [95% CI, 1.02-9.12], respectively) and extended hospital stays (aOR, 1.54 [95% CI, 1.41-1.67], and aOR, 1.71 [95% CI, 1.42-2.05], respectively), while increasing age was not. Increasing frailty (aOR, 0.61 [95% CI, 0.56-0.67]), age (aOR, 0.98 [95% CI, 0.97-0.99]), and non-White race/ethnicity (aOR, 0.62 [95% CI 0.51-0.75]) were all independently associated with routine discharge.

Conclusions and Relevance

In this cross-sectional study, findings suggest that frailty may be more accurate for predicting outcomes and guiding treatment decisions than advanced patient age alone following VS resection.

What Should a Clinician Do When Spreading Depolarizations are Observed in a Patient?

The International Conference on Spreading Depolarizations (iCSD) held in Boca Raton, Florida, in the September of 2018 devoted a section to address the question, "What should a clinician do when spreading depolarizations are observed in a patient?" Discussants represented a wide range of expertise, including neurologists, neurointensivists, neuroradiologists, neurosurgeons, and pre-clinical neuroscientists, to provide both clinical and basic pathophysiology perspectives. A draft summary of viewpoints offered was then written by a multidisciplinary writing group of iCSD members, based on a transcript of the session. Feedback of all discussants was formally collated, reviewed, and incorporated into the final document which was subsequently approved by all authors.

Reliability of the Diagnosis of Cerebral Vasospasm Using Catheter Cerebral Angiography: A Systematic Review and Inter- and Intraobserver Study

BACKGROUND AND PURPOSE

Conventional angiography is the benchmark examination to diagnose cerebral vasospasm, but there is limited evidence regarding its reliability. Our goals were the following: 1) to systematically review the literature on the reliability of the diagnosis of cerebral vasospasm using conventional angiography, and 2) to perform an agreement study among clinicians who perform endovascular treatment.

MATERIALS AND METHODS

Articles reporting a classification system on the degree of cerebral vasospasm on conventional angiography were systematically searched, and agreement studies were identified. We assembled a portfolio of 221 cases of patients with subarachnoid hemorrhage and asked 17 raters with different backgrounds (radiology, neurosurgery, or neurology) and experience (junior ≤10 and senior >10 years) to independently evaluate cerebral vasospasm in 7 vessel segments using a 3-point scale and to evaluate, for each case, whether findings would justify endovascular treatment. Nine raters took part in the intraobserver reliability study.

RESULTS

The systematic review showed a very heterogeneous literature, with 140 studies using 60 different nomenclatures and 21 different thresholds to define cerebral vasospasm, and 5 interobserver studies reporting a wide range of reliability (κ = 0.14-0.87). In our study, only senior raters reached substantial agreement (κ ≥ 0.6) on vasospasm of the supraclinoid ICA, M1, and basilar segments and only when assessments were dichotomized (presence or absence of ≥50% narrowing). Agreement on whether to proceed with endovascular management of vasospasm was only fair (κ ≤ 0.4).

CONCLUSIONS

Research on cerebral vasospasm would benefit from standardization of definitions and thresholds. Dichotomized decisions by experienced readers are required for the reliable angiographic diagnosis of cerebral vasospasm.

The Long-Acting D3 Partial Agonist MC-25-41 Attenuates Motivation for Cocaine in Sprague-Dawley Rats

The dopamine D3 receptor is a prime target for developing treatments for cocaine use disorders (CUDs). In this study, we conducted a pre-clinical investigation of the therapeutic potential of a long-acting, D3 receptor partial agonist, MC-25-41. Male rats were pre-treated with MC-25-41 (vehicle, 1.0, 3.0, 5.6, or 10 mg/kg, intraperitoneal (IP)) five minutes prior to tests of cocaine or sucrose intake on either a progressive ratio schedule of reinforcement or a variable interval 60 s multiple schedule consisting of 4, 15-min components with sucrose or cocaine available in alternating components. A separate cohort of rats was tested on a within-session, dose-reduction procedure to determine the effects of MC-25-41 on demand for cocaine using a behavioral economics analysis. Finally, rats were tested for effects of MC-25-41 on spontaneous and cocaine-induced locomotion. MC-25-41 failed to alter locomotion, but reduced reinforcement rates for both cocaine and sucrose on the low-effort, multiple schedule. However, on the higher-effort, progressive ratio schedule of cocaine reinforcement, MC-25-41 reduced infusions, and active lever presses at doses that did not alter sucrose intake. The behavioral economics analysis showed that MC-25-41 also increased cocaine demand elasticity compared to vehicle, indicating a reduction in consumption as price increases. Together, these results suggest that similar to other D3-selective antagonists and partial agonists, MC-25-41 reduces motivation for cocaine under conditions of high cost but has the added advantage of a long half-life (>10 h). These findings suggest that MC-25-41 may be a suitable pre-clinical lead compound for development of medications to treat CUDs.

AB1358-HPR DIAGNOSIS OF AXIAL SPONDYLOARTHRITIS: A PRIMARY UNMET EDUCATIONAL NEED FOR RHEUMATOLOGISTS

Background:

Diagnosis of axial spondyloarthritis (axSpA) is challenging because of absent physical findings in early disease and the limited diagnostic performance of laboratory markers. Considerable reliance is placed on imaging of the sacroiliac joints (SIJ) but specialty training is primarily focused on interpretation of plain radiographic abnormalities.

Objectives:

We aimed to identify what might be the primary unmet educational needs of rheumatologists completing fellowship training by using clinical and imaging data from an inception cohort of patients presenting with undiagnosed back pain. We hypothesized that concordance would increase after imaging is reviewed after the clinical data.

Methods:

The diagnosis of axSpA was compared between local rheumatologists, axSpA experts and pF using clinical and imaging data from the multicenter Screening for Axial Spondyloarthritis in Psoriasis, Iritis, and Colitis (SASPIC) Study. In this inception cohort, patients ≤45 years of age with ≥3 months back pain undergo diagnostic evaluation by a local SASPIC rheumatologist, including imaging of the SIJ, who then records a global evaluation of presence/absence of axial SpA. This is done at 3 consecutive stages: 1.After the clinical evaluation. 2.After the results of labs (HLA B27, CRP) and radiography. 3.After review of the local MRI. In this exercise, 20 cases were selected from the SASPIC cohort and the rheumatologist global evaluations were removed from the eCRFs. Four experts in axSpA reviewed the clinical and imaging data in each eCRF and provided their global evaluations for stages 1, 2, and 3 of these 20 cases. Subsequently, 4 pF rheumatologists conducted the same exercise blinded to the assessments of the local rheumatologist and experts in axSpA. Concordance (% agreement) between the assessors was analyzed.

Results:

Diagnosis of axSpA by the local SASPIC rheumatologist was made in 90%, 65%, and 75% of cases after stages 1, 2, and 3, respectively. Majority diagnosis of axSpA by experts was made in 84.2% (16/19), 57.9% (11/19), and 63.2% (12/19), after stages 1,2, and 3, respectively. Majority diagnosis of axSpA by pF rheumatologists was made in 94.4% (17/18), 100% (16/16), and 93.8% (15/16). Concordance among experts and between experts and local SASPIC rheumatologists increased after review of imaging data. For pf-rheumatologists concordance with experts increased after review of imaging for 2 assessors and decreased for the other 2 assessors. For the latter, the primary reason for decrease in concordance with experts was false positive diagnosis of axSpA in 35% and 30% of the cases after review of the imaging.

Conclusion:

A structured case-based and sequential evaluation of clinical and imaging data suggests a gap in the training of recently graduated rheumatologists, with over-interpretation of imaging leading to false positive diagnosis of axSpA.

AssessorsMean % Concordance (range) for diagnosis of axSpAStage 1Stage 2Stage 3Experts in axSpA64.2 (45-80)75.8 (65-85)84.2 (70-95)Local rheumatologist vs Experts in axSpA73.8 (70-80)83.8 (80-85)83.8 (80-90)pF rheumatologist 1 vs Experts consensus78.994.494.7pF rheumatologist 2 vs Experts consensus89.561.168.4pF rheumatologist 3 vs Experts consensus63.272.284.2pF rheumatologist 4 vs Experts consensus89.566.768.4

Disclosure of Interests:

Walter P. Maksymowych Grant/research support from: AbbVie, Novartis, Pfizer, and UCB, Consultant of: AbbVie, Boehringer Ingelheim, Celgene, Eli Lilly, Galapagos, Janssen, Novartis, Pfizer, and UCB, Employee of: Chief Medical Officer of CARE Arthritis Limited, Speakers bureau: AbbVie, Janssen, Novartis, Pfizer, and UCB, Liron Caplan: None declared, Atul Deodhar Grant/research support from: AbbVie, Eli Lilly, GSK, Novartis, Pfizer, UCB, Consultant of: AbbVie, Amgen, Boehringer Ingelheim, Bristol Myer Squibb (BMS), Eli Lilly, GSK, Janssen, Novartis, Pfizer, UCB, Speakers bureau: AbbVie, Amgen, Boehringer Ingelheim, Bristol Myer Squibb (BMS), Eli Lilly, GSK, Janssen, Novartis, Pfizer, UCB, Soha Dolatabadi: None declared, Mark Hwang: None declared, Adam Carlson: None declared, Kelly Steed: None declared, Amanda Carapellucci: None declared, Joel Paschke: None declared, Lianne S. Gensler Grant/research support from: Pfizer, Novartis, UCB, Consultant of: AbbVie, Eli Lilly, GSK, Novartis, UCB

0388 Predictors of Incident Reduced Sleep Efficiency in Community-Dwelling Older Women

Introduction

There is a paucity of longitudinal studies with sleep efficiency (SE) as an outcome measure. Our objective was to examine potential risk factors for incident reduced SE among community-dwelling women in late life.

Methods

We studied 700 women (mean age 82.5 [SD=3.0] years) with a SE ≥70% at the Year 16 (2002-04) visit of the Study of Osteoporotic Fractures with a follow-up measure of SE at the Year 20 (2006-08) visit. SE (percentage of time sleeping while in bed) at both visits was measured using a wrist actigraph with data collected for an average of four 24-hour periods. Women were classified as having incident reduced SE if they had SE <70% at Year 20. Logistic regression was used to estimate the associations between potential risk factors (demographics, lifestyle, use of medications, self-reported medical conditions, functional impairment, frailty, mental and physical health) at Year 16 and reduced SE at Year 20. The association of each candidate risk factor with reduced SE at Year 20 was examined in models adjusted for age, clinical site and continuous SE at Year 16. Candidate risk factors with Benjamin Hochberg false-discovery rate q-values <0.10 were included in a final multivariate model.

Results

Among the 700 eligible women, 62 (8.9%) developed incident reduced SE between the Year 16 and Year 20 visits. After adjusting for age, site and baseline SE, antidepressant use [OR=3.06; 95% CI: 1.50-6.25], benzodiazepine use [OR=2.97; 95% CI: 1.30-6.80] and the presence of hypertension [OR=2.83; 95% CI: 1.47-5.45] at Year 16 were independently associated with a higher odds of having reduced SE at follow-up.

Conclusion

These findings suggest that antidepressant use, benzodiazepine use and hypertension are risk factors or markers for the development of reduced sleep efficiency in older women. Future studies are warranted to examine the underlying mechanisms for these associations.

Support

The Study of Osteoporotic Fractures (SOF) is supported by National Institutes of Health funding. The National Institute on Aging (NIA) provides support under the following grant numbers: R01 AG005407, R01 AR35582, R01 AR35583, R01 AR35584, R01 AG005394, R01 AG027574, and R01 AG027576.

Estimating relative CWD susceptibility and disease progression in farmed white-tailed deer with rare PRNP alleles

Chronic wasting disease is a prion disease affecting both free-ranging and farmed cervids in North America and Scandinavia. A range of cervid species have been found to be susceptible, each with variations in the gene for the normal prion protein, PRNP, reportedly influencing both disease susceptibility and progression in the respective hosts. Despite the finding of several different PRNP alleles in white-tailed deer, the majority of past research has focused on two of the more common alleles identified-the 96G and 96S alleles. In the present study, we evaluate both infection status and disease stage in nearly 2100 farmed deer depopulated in the United States and Canada, including 714 CWD-positive deer and correlate our findings with PRNP genotype, including the more rare 95H, 116G, and 226K alleles. We found significant differences in either likelihood of being found infected or disease stage (and in many cases both) at the time of depopulation in all genotypes present, relative to the most common 96GG genotype. Despite high prevalence in many of the herds examined, infection was not found in several of the reported genotypes. These findings suggest that additional research is necessary to more properly define the role that these genotypes may play in managing CWD in both farmed and free-ranging white-tailed deer, with consideration for factors including relative fitness levels, incubation periods, and the kinetics of shedding in animals with these rare genotypes.

The RISE trial: A Randomized Trial on Intra-Saccular Endobridge devices

BACKGROUND

Wide-necked bifurcation aneurysms (WNBA) are a difficult subset of aneurysms to successfully repair endovascularly, and a number of treatment adjuncts have been designed to improve on the results of coiling, including stenting and flow diversion of the parent vessel. Surgical clipping is commonly performed for certain WNBAs, such as middle cerebral aneurysms, in some centres. Intra-saccular flow diversion (ISFD) using the Woven Endo-Bridge (WEB) or similar devices, has been developed as a new endovascular alternative to coiling for WNBAs. Meta-analyses of case series suggest satisfactory results, both in terms of safety and efficacy, but in the absence of randomized evidence, whether ISFD leads to better outcomes for patients with WNBA remains unknown. There is a need to offer ISFD within the context of a randomized care trial.

METHODS

The proposed trial is a multicentre, randomized controlled care trial comparing ISFD and best conventional management option (surgical or endovascular), as determined by the treating physician prior to randomized allocation. At least 250 patients will be recruited in at least 10 centres over a four-year period, and followed for one year, to show that ISFD can increase the incidence of successful therapy from 75 to 90% of patients, defined as complete or near-complete occlusion of the aneurysm AND a good clinical outcome (mRS ≤ 2) at one year. The trial will be followed by an independent data safety monitoring committee to assure the safety of participants.

CONCLUSION

Introduction of intra-saccular flow diversion can be accomplished within a care trial context.

Dermatologic Aspects of Systemic Vasculitis

Systemic and localized vasculitis affects the skin and subcutis, due to large vascular beds and hemodynamic factors, such as stasis in lower extremities, and environmental influences, as occur in cold exposure. Initial cutaneous manifestations of vasculitides include diverse and dynamic patterns of discoloration, swelling, hemorrhage, and necrosis. One-half of affected patients present with localized, self-limited disease to the skin without any known trigger or associated systemic disease, known as idiopathic cutaneous leukocytoclastic vasculitis. Skin biopsy and dermatopathology contribute relevant information; however, they require correlation with clinical history, physical examination, and laboratory findings to reach an accurate diagnosis.

Melanotic neuroectodermal tumor of infancy: A rare pediatric head and neck lesion

Melanotic neuroectodermal tumors of infancy are rare tumors arising from the neural crest and typically present during the first 12 months of life. The majority involve the facial bones, although melanotic neuroectodermal tumors of infancy of the skull and extremities have been observed with less frequency, as in the present case. This entity may initially be presented to the dermatologist as a scalp mass and should be considered in the differential diagnosis of infants with rapidly growing head and neck lesions.

Safety and efficacy of thrombopoeitin mimetics for refractory immune thrombocytopenia purpura in patients with systemic lupus erythematosus or antiphospholipid syndrome: a case series

Background

While thrombopoeitin (TPO) agonists that act to simulate platelet production have been approved for use in steroid-refractory chronic immune thrombocytopenia purpura (ITP), there are few data on the safety and efficacy of these medications in patients with concurrent systemic lupus erythematosus (SLE) or antiphospholipid syndrome (APS). Given that these agents can increase all hematopoietic cell lineages, it is unclear if there is an increased risk for exacerbation of the underlying lymphocyte-driven autoimmune disease in this population.

Case summaries

This case series includes four patients with SLE, one with concurrent APS, who were treated for steroid-refractory ITP with TPO mimetics at the University of Virginia between 2005 and 2015. In three of the four cases the medication was successful in improving platelet counts and preventing bleeding events. In addition, none of the patients experienced thrombosis or worsening of their underlying autoimmune disease.

Conclusions

This case series suggests that TPO mimetics are safe and moderately effective in patients with ITP in the setting of SLE or APS and do not contribute to increased disease activity.

Terminal spreading depolarization and electrical silence in death of human cerebral cortex

OBJECTIVE

Restoring the circulation is the primary goal in emergency treatment of cerebral ischemia. However, better understanding of how the brain responds to energy depletion could help predict the time available for resuscitation until irreversible damage and advance development of interventions that prolong this span. Experimentally, injury to central neurons begins only with anoxic depolarization. This potentially reversible, spreading wave typically starts 2 to 5 minutes after the onset of severe ischemia, marking the onset of a toxic intraneuronal change that eventually results in irreversible injury.

METHODS

To investigate this in the human brain, we performed recordings with either subdural electrode strips (n = 4) or intraparenchymal electrode arrays (n = 5) in patients with devastating brain injury that resulted in activation of a Do Not Resuscitate-Comfort Care order followed by terminal extubation.

RESULTS

Withdrawal of life-sustaining therapies produced a decline in brain tissue partial pressure of oxygen (p_ti O₂ ) and circulatory arrest. Silencing of spontaneous electrical activity developed simultaneously across regional electrode arrays in 8 patients. This silencing, termed "nonspreading depression," developed during the steep falling phase of p_ti O₂ (intraparenchymal sensor, n = 6) at 11 (interquartile range [IQR] = 7-14) mmHg. Terminal spreading depolarizations started to propagate between electrodes 3.9 (IQR = 2.6-6.3) minutes after onset of the final drop in perfusion and 13 to 266 seconds after nonspreading depression. In 1 patient, terminal spreading depolarization induced the initial electrocerebral silence in a spreading depression pattern; circulatory arrest developed thereafter.

INTERPRETATION

These results provide fundamental insight into the neurobiology of dying and have important implications for survivable cerebral ischemic insults. Ann Neurol 2018;83:295-310.

Anticancer effects of resveratrol in canine hemangiosarcoma cell lines

Hemangiosarcoma (HSA) is a highly malignant tumour with aggressive biological behaviour. HSAs are more common in dogs than other domestic animals. The median survival time of dogs with HSA remains short, even with chemotherapy and surgery. Therefore, there is a critical need to improve the adjuvant chemotherapeutic regimens to improve clinical outcomes in dogs with HSA. Resveratrol has been shown to possess strong anti-proliferative and/or pro-apoptotic properties in human cancer cell lines. Nevertheless, the potential anticancer effects of resveratrol have not been reported in canine HSAs. The objective of this study is to determine the growth inhibitory effects of resveratrol in HSA cells when used alone or in combination with doxorubicin, a commonly used chemotherapeutic agent. Frog and DD-1 canine HSA cell lines were treated with varying concentrations of resveratrol with and without doxorubicin. Cell viability was measured by the MTT assay. The expression of apoptotic proteins, activation of p38 mitogen-activated protein kinase (MAPK), AMP-activated protein kinase (AMPK) and extracellular signal-regulated kinase 1/2 (ERK1/2) were assessed by western blotting. Similar to human cancer cell lines, resveratrol markedly inhibited the growth and induced apoptosis in both HSA cell lines. Mechanistically, resveratrol activated p38 MAPK, but did not affect the AMPK or the ERK1/2 pathways. Additional experiments showed that resveratrol augmented the growth-inhibitory and apoptotic effects of doxorubicin in both HSA cell lines. These findings suggest that resveratrol has pro-apoptotic effects in canine HSA cells; therefore, its use as a potential adjunct therapy in canine HSA patients warrants further investigation.

Investigation of Wide Bandgap Semiconductors for Thermoelectric Applications

Thermoelectric materials with stable mechanical and chemical properties at high temperature are required for power generation applications. For example, gas temperatures up to 1000°C are normally present in the waste stream of industrial processes and this can be used for electricity generation. There are few semiconductor materials that can operate effectively at these high temperatures. One solution may be the use of wide bandgap materials, and in particular GaN-based materials, which may offer a traditional semiconductor solution for high temperatures thermoelectric power generation. In particular, the ability to both grow GaN-based materials and fabricate them into devices is well understood if their thermoelectric properties are favorable. To investigate the possibility of using III-Nitride and its alloys for thermoelectric applications, we synthesized and characterized room temperature thermoelectric properties of metal organic chemical vapor deposition grown GaN and InGaN with different carrier concentrations and indium compositions. The promising value of Seebeck coefficients and power factors of Si-doped GaN and InGaN indicated that these materials are suitable for thermoelectric applications.

Transfer printing techniques for materials assembly and micro/nanodevice fabrication

Transfer printing represents a set of techniques for deterministic assembly of micro-and nanomaterials into spatially organized, functional arrangements with two and three-dimensional layouts. Such processes provide versatile routes not only to test structures and vehicles for scientific studies but also to high-performance, heterogeneously integrated functional systems, including those in flexible electronics, three-dimensional and/or curvilinear optoelectronics, and bio-integrated sensing and therapeutic devices. This article summarizes recent advances in a variety of transfer printing techniques, ranging from the mechanics and materials aspects that govern their operation to engineering features of their use in systems with varying levels of complexity. A concluding section presents perspectives on opportunities for basic and applied research, and on emerging use of these methods in high throughput, industrial-scale manufacturing.

Elastomer surfaces with directionally dependent adhesion strength and their use in transfer printing with continuous roll-to-roll applications

In this paper we present mechanics and materials aspects of elastomeric stamps that have angled features of relief on their surfaces, designed to enable control of adhesion strength by peeling direction, in a way that can be exploited in schemes for deterministic assembly by transfer printing. Detailed mechanics models capture the essential physics of interface adhesion in this system. Experiments with cylindrical stamps that have this design demonstrate their potential for use in a continuous, roller mode of operation.

Utility of routine follow-up head CT scanning after mild traumatic brain injury: a systematic review of the literature

OBJECTIVE

To evaluate the efficacy of routine follow-up CT scans of the head after complicated mild traumatic brain injury (TBI).

METHODS

74 English language studies published from 1999 to February 2011 were reviewed. The papers were found by searching the PubMed database using a combination of keywords according to Cochrane guidelines. Excluding studies with missing or inappropriate data, 1630 patients in 19 studies met the inclusion criteria: complicated mild TBI, defined as a GCS score 13-15 with abnormal initial CT findings and the presence of follow-up CT scans. For these studies, the progression and type of intracranial haemorrhage, time from trauma to first scan, time between first and second scans, whether second scans were obtained routinely or for neurological decline and the number of patients who had a neurosurgical intervention were recorded.

RESULTS

Routine follow-up CT scans showed hemorrhagic progression in 324 patients (19.9%). Routine follow-up head CT scans did not predict the need for neurosurgical intervention (p=0.10) but a CT scan of the head performed for decline in status did (p=0.00046). For the 56 patients (3.4%) who declined neurologically, findings on the second CT scan were worse in 38 subjects (67%) and unchanged in the rest. Overall, 39 patients (2.4%) underwent neurosurgical intervention.

CONCLUSION

Routine follow-up CT scans rarely alter treatment for patients with complicated mild TBI. Follow-up CT scans based on neurological decline alter treatment five times more often than routine follow-up CT scans.

Thermohydrodynamics of boiling in a van der Waals fluid

We present a modeling approach that enables numerical simulations of a boiling Van der Waals fluid based on the diffuse interface description. A boundary condition is implemented that allows in and out flux of mass at constant external pressure. In addition, a boundary condition for controlled wetting properties of the boiling surface is also proposed. We present isothermal verification cases for each element of our modeling approach. By using these two boundary conditions we are able to numerically access a system that contains the essential physics of the boiling process at microscopic scales. Evolution of bubbles under film boiling and nucleate boiling conditions are observed by varying boiling surface wettability. We observe flow patters around the three-phase contact line where the phase change is greatest. For a hydrophilic boiling surface, a complex flow pattern consistent with vapor recoil theory is observed.

Large-area flexible 3D optical negative index metamaterial formed by nanotransfer printing

Negative-index metamaterials (NIMs) are engineered structures with optical properties that cannot be obtained in naturally occurring materials. Recent work has demonstrated that focused ion beam and layer-by-layer electron-beam lithography can be used to pattern the necessary nanoscale features over small areas (hundreds of µm(2)) for metamaterials with three-dimensional layouts and interesting characteristics, including negative-index behaviour in the optical regime. A key challenge is in the fabrication of such three-dimensional NIMs with sizes and at throughputs necessary for many realistic applications (including lenses, resonators and other photonic components). We report a simple printing approach capable of forming large-area, high-quality NIMs with three-dimensional, multilayer formats. Here, a silicon wafer with deep, nanoscale patterns of surface relief serves as a reusable stamp. Blanket deposition of alternating layers of silver and magnesium fluoride onto such a stamp represents a process for 'inking' it with thick, multilayer assemblies. Transfer printing this ink material onto rigid or flexible substrates completes the fabrication in a high-throughput manner. Experimental measurements and simulation results show that macroscale, three-dimensional NIMs (>75 cm(2)) nano-manufactured in this way exhibit a strong, negative index of refraction in the near-infrared spectral range, with excellent figures of merit.

Stretchable ferroelectric nanoribbons with wavy configurations on elastomeric substrates

Applications of ferroelectric ceramics, ranging from components for sensors, memory devices, microelectromechanical systems, and energy convertors, all involve planar and rigid layouts. The brittle nature of such materials and their high-temperature processing requirements limit applications to devices that involve only very small mechanical deformations and narrow classes of substrates. Here, we report a strategy for integrating nanoribbons of one of the most widely used ferroelectric ceramics, lead zirconate titanate, in "wavy" geometries, on soft, elastomeric supports to achieve reversible, linear elastic responses to large strain deformations (i.e., stretchable properties), without any loss in ferroelectric or piezoelectric properties. Theoretical and computational analysis of the mechanics account for these characteristics and also show that the amplitudes of the waves can be continuously tuned with an applied electric field, to achieve a vertical (normal) displacement range that is near 1000 times larger than is possible in conventional planar layouts. The results suggest new design and application possibilities in piezoelectric devices.

Low-cost, take-home, beating heart simulator for health-care education

Intended for medical students studying the evaluation and diagnosis of heart arrhythmias, the beating heart arrhythmia simulator combines visual, auditory, and tactile stimuli to enhance the student's retention of the subtle differences between various conditions of the heart necessary for diagnosis. Unlike existing heart arrhythmia simulators, our simulator is low cost and easily deployable in the classroom setting. A design consisting of solenoid actuators, a silicon heart model, and a graphical user interface has been developed and prototyped. Future design development and conceptual validation is necessary prior to deployment.

Awareness of the phototoxic effects of sunlight among South African university students

Due tothe depletion of the atmospheric ozone, there is currently a great concern for the phototoxic effects of sunlight on humans worldwide. The purpose of this study was to evaluate the awareness of the phototoxic effects of sunlight among a sample of South African university students.  A questionnaire on awareness of the adverse effects of excessive exposure to sunlight was completed by the participants and findings were analyzed. Ages of the participants (n=1832) ranged from 17 to 55 years (mean = 21.03 ± 3.44) and there were 43.7% males and 56.3% females.  Many, (73.9%) agreedthat excessive exposure to the sun is harmful to health, but only 56.9% could adequately explain how it is harmful to health.  Many, (68.2%) agreed that fair-skinned individuals are more likely to be affected by the sun than dark-skinned ones.  Only 52% reported that childhood exposure to sunlight is more dangerous than adulthood exposure. A few (32.9%) agreed that short term intensive exposure was more dangerous than chronic regular moderate exposures.  Although 72.3% had heard about ultraviolet (UV) radiation, only 47.1% had heard of cataracts and fewer (25.7%) agreed that cataracts can be caused by UVR exposure.  A few (28.7%) had heard of macular degeneration, but only 17.6% agreed that it can be caused by UVR.  Although awareness was good in certain aspects, it was poor in others; suggesting the need for an awareness campaign among South Africans. It is recommended that the awareness campaign should include avoidance of excessive exposure and the use of appropriate protective devices. (S Afr Optom 2010 69(3) 146-151)

Effect of bexarotene on platelet counts in patients undergoing cancer treatment: An analysis of clinical trials in lung cancer and leukemia

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Background: Bexarotene (Bex) is an oral retinoid X receptor agonist with activity against cutaneous T cell lymphoma and currently under investigation for other malignancies. In patients receiving this agent for acute myeloid leukemia (AML), we noted increases in platelet counts. We therefore reviewed the available clinical trial data on Bex and its effects on platelet counts. Methods: We analyzed platelet count data from 3 Bex clinical trials encompassing non-small cell lung cancer (NSCLC) and AML. Results: In two phase III trials of Bex in NSCLC, patients underwent carboplatin + paclitaxel (CarP, n=587) or cisplatin + vinorelbine (CisV, n=613) and were randomized to receive concurrent Bex or placebo. More patients on Bex than on placebo had an increase in platelet count of at least 50 K/uL (55% vs. 27% for CarP, p<0.0001; 81% vs. 66% for CisV, p<0.0001) over pre-treatment baseline. The median increase in platelet count was higher on Bex than on placebo (69 vs 0 K/uL for CarP, p<0.0001; 168 vs. 95 K/uL for CisV, p<0.0001) and was maintained while on treatment. In both NSCLC trials, the median time to platelet increase >50 K/uL on Bex was 22 days. Similar findings were seen in a phase I monotherapy trial in AML where 5/18 (28%) patients achieved platelet transfusion independence with peak platelet counts of 40–91 K/uL. Conclusions: Clinically significant increases in platelet counts were seen in all 3 clinical trials examined. These data suggest that Bex improves platelet counts in patients with a variety of cancer types, both as monotherapy and with concurrent chemotherapy. Its effect on megakaryopoiesis and its potential role as a supportive care measure should be further evaluated.

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