bluuebunny/crossref_metadata_2025 huggingface dataset:
Linear Accelerator Radiosurgery for Cavernous Sinus Meningiomas
Authors: Kimball Matthew M. , Friedman William A. , Foote Kelly D. , Bova Frank J. , Chi Yueh-Yun
Published: February 2009

Objective: In this paper, the authors review the results of a single-center experience using linear accelerator (LINAC) radiosurgery for the treatment of cavernous sinus meningiomas. Methods: This is a retrospective analysis with a median follow-up of 50 months. All patients were treated on an outpatient basis. Fifty-five patients were treated and 6 patients were lost to follow-up. Changes in preradiosurgery cranial nerve deficits and symptoms as well as actuarial local tumor control were evaluated. Results:The actuarial local tumor control was 100% at 5 years and 98% at 10 years. One patient had enlargement of tumor. Sixty-five percent had improvement in preradiosurgery cranial nerve deficits, 31% were unchanged and 1 patient (3.5%) was worse. Only 1 patient developed a new neurologic deficit. Conclusions: This is the largest LINAC radiosurgery experience for cavernous sinus meningiomas reported to date. Radiosurgery appears to offer greatly superior tumor control and much lower morbidity than surgical resection of cavernous sinus meningiomas.
Molecular Studies of an Impetigo Bullosa Epidemic in Full-Term Infants
Authors: Jursa-Kulesza Joanna , Kordek Agnieszka , Kopron Katarzyna , Wojciuk Bartosz , Giedrys-Kalemba Stefania
Published: February 2009

Background: Carriers ofStaphylococcus aureus strains can be the source of epidemic infection for patients. Objectives: A molecular epidemiological analysis of an impetigo bullosa outbreak in a neonatal ward was performed in order to determine a potential source of the infection and possible routes of subsequent spreading of the epidemic strain. Methods: The genetic relatedness of S. aureus strains isolated from 6 neonates with epidermal lesions and from 21 staff members was verified by the pulsed field gel electrophoresis (PFGE) method. Additionally, detection of eta and etb genes of S. aureus strains using PCR was performed. Results: None of the infected newborns’ mothers was a carrier. Seven strains, 6 isolated from the newborns and 1 taken from a midwife, showed the same restriction pattern, i.e. type A. In the other 20 health care workers colonized with S. aureus, 3 genetic types could be distinguished, i.e. B (2), C (7) and D (2), as well as 9 strains with unique PFGE patterns. The eta gene detected in 7 strains belonged to the genetic type A; there was no etb gene in any of the 27 S. aureus isolates. Conclusions: The presence of the same genetic type A of S. aureus in the infected newborns is a factor which indicates that the impetigo bullosa was a hospital infection. A probable source of the infection was a midwife who was colonized with the same S. aureus type. She was present at the birth of the first infected newborn. Today, molecular methods are essential for prompt recognition of an epidemic and implementation of appropriate infection control strategies.
Mild Methionine Excess Does Not Affect Thymidylate Synthesis or Inflammation Markers Expression in Human Aortic Endothelial Cells
Authors: Achón María , Alonso-Aperte Elena , Varela-Moreiras Gregorio , Selhub Jacob
Published: February 2009

Background: Recent studies in animal models have shown that high methionine intakes induce atherosclerotic changes that may be exacerbated when deficiencies of vitamins B6, B12 and folate are present. However, the mechanism underlying this possible atherogenic effect remains unknown. The aim of the present study was to evaluate the effects of methionine on the folate-dependent thymidylate-DNA synthesis, as a possible mechanism of atherogenicity, as well as the effect of high methionine/low folate on several key inflammation markers, such as vascular cell adhesion molecule-1 (VCAM-1), receptor for advanced glycation end products (RAGE) and matrix metalloproteinase-9 (MMP-9) in human aortic endothelial cells. Methods: Deoxyuridine suppression test was performed in order to evaluate thymidylate synthesis. To examine the expression of inflammation markers, cells were exposed to high methionine/low folate media for 9 days. Results: The assayed methionine levels (0.1, 0.5 and 5 mM) did not affect the de novo thymidylate-DNA synthesis. Consistent with this result, methionine (1 and 2.5 mM), alone or in combination with folate deficiency, increased homocysteine levels but did not induce the expression of the inflammation markers evaluated. Conclusion: Under the study conditions, methionine was not able to exert the atherogenic mechanism proposed and did not have the hypothesized inflammatory consequences in human aortic endothelial cells.
Survival of Bacterial Biofilms within Neutrophil Extracellular Traps Promotes Nontypeable Haemophilus influenzae Persistence in the Chinchilla Model for Otitis Media
Authors: Hong Wenzhou , Juneau Richard A. , Pang Bing , Swords W. Edward
Published: February 2009

Nontypeable Haemophilus influenzae (NTHi) is a leading cause of acute and chronic otitis media, which are a major public health problem worldwide. The persistence of NTHi during chronic and recurrent otitis media infections involves multicellular biofilm communities formed within the middle-ear chamber. Bacterial biofilms resist immune clearance and antibiotic therapy due in part to encasement within a polymeric matrix. In this study, the contribution of biofilms to bacterial persistence in vivo and composition of the NTHi biofilm matrix during experimental otitis media were investigated. The presence of biofilms within the chinchilla middle-ear chamber was significantly correlated with increased bacterial load in middle-ear effusions and tissue. Examination of thin sections revealed polymorphonuclear cells within a DNA lattice containing elastase and histones, which is consistent with the definition of neutrophil extracellular traps. Viable multicellular biofilm communities with biofilm phenotypes were found within the DNA lattice throughout the biofilm. Further, NTHi was resistant to both phagocytic and extracellular neutrophil killing in vitro by means of lipooligosaccharide moieties that promote biofilm formation. These data support the conclusion that NTHi subverts neutrophil extracellular traps to persist in vivo. These data also indicate that a more inclusive definition for biofilms may be warranted.
Comparison of 8-Isoprostane and Interleukin-8 in Induced Sputum and Exhaled Breath Condensate from Asymptomatic and Symptomatic Smokers
Authors: Mazur Witold , Stark Harri , Sovijärvi Anssi , Myllärniemi Marjukka , Kinnula Vuokko L.
Published: February 2009

Background: Markers of airway inflammation and oxidative stress have been mainly investigated in moderate/severe chronic obstructive pulmonary disease (COPD) or during its exacerbation. They have not been compared in noninvasive specimens such as exhaled breath condensate (EBC) and induced sputum in healthy nonsymptomatic smokers or in those who have symptoms and are at risk for COPD development. Objectives: To compare the relative proportions of 2 potential COPD biomarkers, 8-isoprostane and interleukin- 8 (IL-8) in the induced sputum and EBC sampled from the same subjects: nonsmokers (n = 14), healthy smokers (n = 17) and symptomatic smokers (n = 9) who are considered to be at risk for COPD. COPD patients with acute exacerbation (n = 10) were employed as positive controls. Methods: The levels of the aforementioned biomarkers in induced sputum and EBC were investigated using commercial biochemical techniques. Results: In induced sputum, the levels of 8-isoprostane and IL-8 were at least 10-fold higher compared to EBC levels in all groups. Healthy nonsmokers had the lowest levels, and patients with exacerbation of COPD the highest levels of 8-isoprostane in induced sputum and EBC. The same observation held true for IL-8 in induced sputum. Inverse correlations with lung function parameters were observed for both mediators. Conclusions: The levels of both potential markers were clearly higher in the induced sputum than in EBC. The results point to an advantage of induced sputum over EBC for assessing the degree of airway oxidative stress and inflammation in smokers with a potential risk for COPD development.
Effect of Nutrition on Arterial Stiffness in Peritoneal Dialysis Patients
Authors: Tang Wen , Cheng Li-Tao , Lu Xin-Hong , Wang Tao
Published: February 2009

Background: A poor nutritional state is associated with an increased risk of cardiovascular events in end-stage renal disease. It is unclear whether malnutrition itself can induce cardiovascular disease (CVD). We examined the impact of nutritional status on patients’ arterial stiffness in peritoneal dialysis (PD) patients. Methods: We prospectively enrolled 121 stable PD patients and evaluated them at baseline and 1 year later. According to patients’ Subjective Global Assessment (SGA) changes from baseline to the end, patients were divided into four groups: group 1, SGA from A to B; group 2, SGA remained A, group 3, SGA changed from B to A, and group 4, SGA remained B. Arterial stiffness was assessed by pulse-wave velocity (PWV). Results: At baseline, PWV in well-nourished patients were lower than malnourished patients (p < 0.05). One year later, in group 1, as compared with baseline, PWV increased significantly (p < 0.001) whereas handgrip strength (HGS), daily dietary protein intake and dietary energy intake decreased significantly. In group 3, PWV decreased significantly (p < 0.05) whereas HGS and ALB increased significantly. In groups 1 and 3, lgCRP level remained unchanged. Conclusion: There was a closely longitudinal association between nutritional status and arterial stiffness in PD patients, suggesting a possible impact of nutritional status on arterial function.
Novel Strategy Using F1-Congenic Mice for Validation of QTLs
Authors: Teupser Daniel , Wolfrum Susanne , Tan Marietta , Persky Adam D. , Dansky Hayes M. , Breslow Jan L.
Published: February 2009

Objective—

We have previously identified a quantitative trait locus (QTL) for atherosclerosis susceptibility on proximal chromosome 10 (Chr10) (
Ath11
) in independent crosses of FVB and C57BL/6 (B6) mice on the apolipoprotein E (ApoE
−/−
) and LDL receptor (LDLR
−/−
) deficient backgrounds. The aims of the current study were to (1) test a novel strategy for validating QTLs using interval-specific congenic strains that were heterozygous (F1) across the genome, (2) validate the Chr10 QTL, and (3) to assess whether the phenotype is transferable by bone marrow transplantation.

Methods and Results—

We generated Chr10 (0 to 21 cM) interval-specific mice on the F1.ApoE
−/−
background by crossing congenic FVB.ApoE
−/−
Chr10
B6/FVB
with B6.ApoE
−/−
, and B6.ApoE
−/−
Chr10
B6/FVB
with FVB.ApoE
−/−
mice. Lesion size was significantly larger in the resultant F1.ApoE
−/−
Chr10
FVB/FVB
mice compared to F1.ApoE
−/−
Chr10
B6/FVB
and F1.ApoE
−/−
Chr10
B6/B6
mice, validating the Chr10 QTL. The effect of the congenic interval was more robust on the F1.ApoE
−/−
than on the FVB.ApoE
−/−
and B6.ApoE
−/−
backgrounds. Bone marrow transplantation in congenic mice showed that the effect of the proximal Chr10 interval was not transferable by bone marrow–derived cells.

Conclusions—

A novel strategy of congenic strains on an F1 background proved useful to validate an atherosclerosis susceptibility QTL on mouse proximal Chr10.
Prolonged Exposure to LPS Increases Iron, Heme, and p22
phox
Levels and NADPH Oxidase Activity in Human Aortic Endothelial Cells
Authors: Li Lixin , Frei Balz
Published: February 2009

Objective—

Vascular oxidative stress and inflammation are contributing factors in atherosclerosis. We recently found that the iron chelator, desferrioxamine (DFO), suppresses NADPH oxidase-mediated oxidative stress and expression of cellular adhesion molecules in mice treated with lipopolysaccharide (LPS). The objective of the present study was to investigate whether and how LPS and iron enhance, and DFO inhibits, NADPH oxidase activity in human aortic endothelial cells (HAECs).

Methods and Results—

Incubation of HAECs for 24 hours with 5 μg/mL LPS led to a 4-fold increase in NADPH oxidase activity, which was strongly suppressed by pretreatment of the cells for 24 hours with 100 μmol/L DFO. Incubating HAECs with LPS also significantly increased cellular iron and heme levels and mRNA and protein levels of p22
phox
, a heme-containing, catalytic subunit of NADPH oxidase. All of these effects of LPS on HAECs were strongly inhibited by DFO. Exposing HAECs to 100 μmol/L iron (ferric citrate) for 48 hours exerted similar effects as LPS, and these effects were strongly inhibited by coincubation with DFO. Furthermore, neither LPS nor DFO affected mRNA and protein levels of p47
phox
a nonheme–containing, regulatory subunit of NADPH oxidase, or the mRNA level of NOX4, an isoform of the principal catalytic subunit of NADPH oxidase in endothelial cells. In contrast, heme oxygenase-1 was strongly suppressed by DFO, both in the absence and presence of LPS or iron.

Conclusions—

Our data indicate that prolonged exposure to LPS or iron increases endothelial NADPH oxidase activity by increasing p22
phox
gene transcription and cellular levels of iron, heme, and p22
phox
protein. Iron chelation by DFO effectively suppresses endothelial NADPH oxidase activity, which may be helpful as an adjunct in reducing vascular oxidative stress and inflammation in atherosclerosis.
Gelsolin Regulates Cardiac Remodeling After Myocardial Infarction Through DNase I–Mediated Apoptosis
Authors: Li Guo Hua , Shi Yu , Chen Yu , Sun Mei , Sader Sawsan , Maekawa Yuichiro , Arab Sara , Dawood Fayez , Chen Manyin , De Couto Geoffrey , Liu Youan , Fukuoka Masahiro , Yang Stanley , Da Shi Ming , Kirshenbaum Lorrie A. , McCulloch Christopher A. , Liu Peter
Published: February 2009

Gelsolin, a calcium-regulated actin severing and capping protein, is highly expressed in murine and human hearts after myocardial infarction and is associated with progression of heart failure in humans. The biological role of gelsolin in cardiac remodeling and heart failure progression after injury is not defined. To elucidate the contribution of gelsolin in these processes, we randomly allocated gelsolin knockout mice (GSN
−/−
) and wild-type littermates (GSN
+/+
) to left anterior descending coronary artery ligation or sham surgery. We found that GSN
−/−
mice have a surprisingly lower mortality, markedly reduced hypertrophy, smaller late infarct size, less interstitial fibrosis, and improved cardiac function when compared with GSN
+/+
mice. Gene expression and protein analysis identified significantly lower levels of deoxyribonuclease (DNase) I and reduced nuclear translocation and biological activity of DNase I in GSN
−/−
mice. Absence of gelsolin markedly reduced DNase I–induced apoptosis. The association of hypoxia-inducible factor (HIF)-1α with gelsolin and actin filaments cleaved by gelsolin may contribute to the higher activation of DNase. The expression pattern of HIF-1α was similar to that of gelsolin, and HIF-1α was detected in the gelsolin complex by coprecipitation and HIF-1α bound to the promoter of DNase I in both gel-shift and promoter activity assays. Furthermore, the phosphorylation of Akt at Ser473 and expression of Bcl-2 were significantly increased in GSN
−/−
mice, suggesting that gelsolin downregulates prosurvival factors. Our investigation concludes that gelsolin is an important contributor to heart failure progression through novel mechanisms of HIF-1α and DNase I activation and downregulation of antiapoptotic survival factors. Gelsolin inhibition may form a novel target for heart failure therapy.
Structural and Functional Evidence for Discrete Exit Pathways That Connect the Canine Sinoatrial Node and Atria
Authors: Fedorov Vadim V. , Schuessler Richard B. , Hemphill Matthew , Ambrosi Christina M. , Chang Roger , Voloshina Alexandra S. , Brown Kathy , Hucker William J. , Efimov Igor R.
Published: February 2009

Surface electrode recordings cannot delineate the activation within the human or canine sinoatrial node (SAN) because they are intramural structures. Thus, the site of origin of excitation and conduction pathway(s) within the SAN of these mammals remains unknown. Canine right atrial preparations (n=7) were optically mapped. The SAN 3D structure and protein expression were mapped using immunohistochemistry. SAN optical action potentials had diastolic depolarization and multiple upstroke components that corresponded to the separate excitations of the node and surface atrial layers. Pacing-induced SAN exit block eliminated atrial optical action potential components but retained SAN optical action potential components. Excitation originated in the SAN (cycle length, 557±72 ms) and slowly spread (1.2 to 14 cm/sec) within the SAN, failing to directly excite the crista terminalis and intraatrial septum. After a 49±22 ms conduction delay within the SAN, excitation reached the atrial myocardium via superior and/or inferior sinoatrial exit pathways 8.8±3.2 mm from the leading pacemaker site. The ellipsoidal 13.7±2.8/4.9±0.6 mm SAN structure was functionally insulated from the atrium. This insulation coincided with connexin43-negative regions at the borders of the node, connective tissue, and coronary arteries. During normal sinus rhythm, the canine SAN is functionally insulated from the surrounding atrial myocardium except for 2 (or more) narrow superior and inferior sinoatrial exit pathways separated by 12.8±4.1 mm. Conduction failure in these sinoatrial exit pathways leads to SAN exit block and is a modulator of heart rate.
Effectiveness of Prism Adaptation in Neglect Rehabilitation
Authors: Serino Andrea , Barbiani Moreno , Rinaldesi Maria Luisa , Làdavas Elisabetta
Published: February 2009

Background and Purpose—

This study was conducted to investigate the effectiveness on neglect recovery of a 2-week treatment based on prism adaptation (PA) in comparison to an analogous visuomotor training performed without prisms, ie, neutral pointing (NP).

Methods—

Twenty neglect patients were divided into 2 matched groups, one was submitted to PA (PA group) and the other to NP (NP group) for 10 daily sessions over a period of 2 weeks. After the end of NP treatment, the patients in the NP group were also submitted to PA treatment. Neglect was assessed before and after each treatment and 1 month after the end of the PA treatment.

Results—

Visuospatial abilities improved after both PA and NP treatment; however, the improvement was significantly higher in the patients in the PA group than in the patients in the NP group. Moreover, when the patients in the NP group were submitted to PA, they further improved up to the level reached by patients in the PA group, ie, to nonpathological scores. Long-lasting beneficial effects of PA were confirmed 1 month from the end of treatment.

Conclusion—

The leftward recalibration of sensorimotor reference frames induced by PA is effective to obtain proper neglect recovery, although visuomotor training based on pointing might partially improve neglect symptoms.
Future Demographic Trends Decrease the Proportion of Ischemic Stroke Patients Receiving Thrombolytic Therapy
Authors: Foerch Christian , Sitzer Matthias , Steinmetz Helmuth , Neumann-Haefelin Tobias
Published: February 2009

Background and Purpose—

Thrombolytic therapy with tissue plasminogen activator (tPA) is rarely applied to ischemic stroke patients aged 80 years and above. As future demographic trends will increase the proportion of older stroke patients, the overall tPA treatment rate may decrease. The aim of the present analysis was to provide an estimate of the future number of ischemic stroke patients and the fraction thereof receiving tPA.

Methods—

In 2005, n=12 906 hospitalized ischemic stroke patients were included into a large registry covering the Federal State of Hesse, Germany. Age- and gender-specific frequency rates for ischemic stroke and tPA therapy were calculated based on the registry and the respective population data. Population projections until 2050 were derived from the Hessian Bureau of Statistics.

Results—

Assuming constant age- and gender-specific stroke incidence rates and treatment strategies, the total number of ischemic stroke patients will rise by approximately 68% until 2050, whereas the proportion of tPA-treated ischemic stroke patients will decrease from 4.5% to 3.8% in the same time frame (relative decrease 16%; χ
2
P
<0.001).

Conclusions—

Future demographic changes will reduce tPA treatment rates. Therapeutic studies focusing on very old stroke patients are necessary to counteract this trend.
Expediting MRI-Based Proof-of-Concept Stroke Trials Using an Earlier Imaging End Point
Authors: Ebinger Martin , Christensen Soren , De Silva Deidre A. , Parsons Mark W. , Levi Christopher R. , Butcher Kenneth S. , Bladin Christopher F. , Barber P. Alan , Donnan Geoffrey A. , Davis Stephen M.
Published: February 2009

Background and Purpose—

Before Phase III trials of acute stroke therapies, proof-of-concept MRI trials are increasingly used to gauge the likelihood of success. Given that animal models use infarct volume as the end point, Phase II trials have aimed to translate the findings using infarct growth. These trials could be expedited if subacute diffusion-weighted imaging lesion volume replaced late T2-weighted lesion volume as the primary end point.

Methods—

In the Echoplanar Imaging Thrombolytic Evaluation Trial, patients with acute ischemic stroke presenting within 3 to 6 hours were randomized to tissue plasminogen activator or placebo. We assessed correlations between acute (Day 1), subacute (Day 3 to 5) as well as late (Day 90) lesion volumes and clinical outcome (National Institutes of Health Stroke Scale). We compared lesion growth between placebo- and tissue plasminogen activator-treated patients.

Results—

All 3 scans were performed in 72 of 101 patients (32 tissue plasminogen activator, 40 placebo). Median time to subacute imaging was 3 days (interquartile range, 2 to 4) and 90 days (interquartile range, 90 to 95) for the late scan. Increase in lesion volume from acute to subacute scans was smaller in the tissue plasminogen activator group compared with the placebo group (6.77 mL; interquartile range, 2.30 to 49.10; versus 30.00 mL; interquartile range, 7.19 to 85.93;
P
=0.03). Subsequent shrinkage did not reveal significant treatment effects. Correlation coefficient between acute and late lesion volumes was 0.81 (
P
<0.01). Subacute and late lesion volumes were strongly correlated (rho=0.94,
P
<0.01). Correlation coefficient for acute, subacute, and late lesion volume and late National Institutes of Health Stroke Scale score was 0.64 (
P
<0.01), 0.81 (
P
<0.01), and 0.77 (
P
<0.01), respectively.

Conclusions—

These findings suggest that subacute imaging at Day 3 after thrombolysis is an appropriate imaging end point for proof-of-concept MRI-based stroke treatment trials and can replace later MRI measurements.
Prevalence of Carotid Stenosis in a High-Risk Caribbean Population
Authors: Brown Hilary A. , Lawrence-Wright Marilyn B. , Shah Sundeep , Lawrence Sara G. , Gilbert David , Crandon Ivor
Published: February 2009

Background and Purpose—

The purpose of this study was to determine the prevalence of carotid stenosis among patients presenting to the University Hospital of West Indies (UHWI) Accident and Emergency Department (A&E) with an ischemic stroke or transient ischemic attack (TIA).

Methods—

Beginning in August 2006, all patients presenting to the UHWI A&E with an acute stroke or TIA were screened for enrollment. Patients were excluded if they had a hemorrhagic stroke or if informed consent could not be obtained. Demographic and clinical information were collected by chart review and interviewer-administered questionnaires. All participants had noncontrast head computed tomography (CT) and bilateral carotid duplex ultrasounds.

Results—

133 patients were enrolled in the study. 90% presented with a stroke and 10% with a TIA. Mean age was 64 years, 52% were male, 96% self-identified as black. 78% had diabetes mellitus or hypertension or both, 27% were current or past smokers. 65.1% had a normal carotid ultrasound, 28.5% had <50% stenosis, 1.6% had 50% to 69% stenosis, 0.8% had ≥70% stenosis to near occlusion, 1.6% had near occlusion and 1.6% total occlusion.

Conclusions—

The prevalence of moderate or high-grade carotid stenosis in this high-risk black Caribbean population presenting with an ischemic stroke or a TIA is 5.6%. This is lower than that described in other populations. Further studies are needed to determine the cost-effectiveness of routine screening for carotid stenosis in this population.
Intraventricular Hemorrhage
Authors: Hanley Daniel F.
Published: February 2009

Background and Purpose—

This review focuses on the emerging principles of intracerebral hemorrhage (ICH) management, emphasizing the natural history and treatment of intraventricular hemorrhage. The translational and clinical findings from recent randomized clinical trials are defined and discussed.

Summary of Review—

Brain hemorrhage is the most severe of the major stroke subtypes. Extension of the hemorrhage into the ventricles (a 40% occurrence) can happen early or late in the sequence of events. Epidemiological data demonstrate the amount of blood in the ventricles relates directly to the degree of injury and likelihood of survival. Secondary tissue injury processes related to intraventricular bleeding can be reversed by removal of clot in animals. Specific benefits of removal include limitation of inflammation, edema, and cell death, as well as restoration of cerebral spinal fluid flow, intracranial pressure homeostasis, improved consciousness, and shortening of intensive care unit stay. Limited clinical knowledge exists about the benefits of intraventricular hemorrhage (IVH) removal in humans, because organized attempts to remove blood have not been undertaken in large clinical trials on a generalized scale. New tools to evaluate the volume and location of IVH and to test the benefits/risks of removal have been used in the clinical domain. Initial efforts are encouraging that increased survival and functional improvement can be achieved. Little controversy exists regarding the need to scientifically investigate treatment of this severity factor.

Conclusions—

Animal models demonstrate clot removal can improve the acute and long-term consequences of intraventricular extension from intracerebral hemorrhage by using minimally invasive techniques coupled to recombinant tissue plasminogen activator-mediated clot lysis. The most recent human clinical trials show that severity of initial injury and the long-term consequences of blood extending into the ventricles are clearly related to the amount of bleeding into the ventricular system. The failure of the last 2 pivotal brain hemorrhage randomized control trials may well relate to the consequences of intraventricular bleeding. Small proof of concept studies, meta-analyses, and preliminary pharmacokinetics studies support the idea of positive shifts in mortality and morbidity, if this 1 critical disease severity factor, IVH, is properly addressed. Understanding clinical methods for the removal of IVH is required if survival and long-term functional outcome of brain hemorrhage is to improve worldwide.
Association Between Age-Related Hearing Loss and Stroke in an Older Population
Authors: Gopinath Bamini , Schneider Julie , Rochtchina Elena , Leeder Stephen R. , Mitchell Paul
Published: February 2009

Background and Purpose—

Very few studies have investigated the association between hearing loss and stroke. A recent article in
Stroke
reported an increased incidence of stroke among patients with sudden hearing loss over a 5-year follow-up period. Our study aimed to explore this association among subjects with age-related hearing loss from a representative population. Further, we looked at the association between severity of hearing loss and risk of stroke in older persons, acknowledged as a limitation by the authors of the
Stroke
report.

Methods—

The Blue Mountains Hearing Study is a population-based survey of age-related hearing loss conducted during 1997 to 1999 and 2002 to 2004, among participants of the Blue Mountains Eye Study. Pure-tone air conduction hearing thresholds from 0.25 to 8.0 kHz were measured by audiologists. Hearing loss was defined as the pure-tone average of frequencies 0.5, 1.0, 2.0, and 4.0 kHz >25 dB HL in the better ear.

Results—

Persons with moderate to severe hearing loss had a significantly higher likelihood of reporting previous stroke (OR, 2.04; 95% CI, 1.20–3.49) after multivariable adjustment. However, moderate to severe hearing loss did not predict incident stroke after 5-year follow-up (OR, 1.14; 95% CI, 0.59–2.23).

Conclusions—

We observed a strong cross-sectional association between stroke and moderate to severe hearing loss. However, age-related hearing loss did not increase risk of incident stroke in our cohort. Insufficient study power or differing underlying pathologies of sudden sensorineural hearing loss and typical age-related hearing loss may account for the discrepant findings between these studies.
Update of the Stroke Therapy Academic Industry Roundtable Preclinical Recommendations
Authors: Fisher Marc , Feuerstein Giora , Howells David W. , Hurn Patricia D. , Kent Thomas A. , Savitz Sean I. , Lo Eng H.
Published: February 2009

The initial Stroke Therapy Academic Industry Roundtable (STAIR) recommendations published in 1999 were intended to improve the quality of preclinical studies of purported acute stroke therapies. Although recognized as reasonable, they have not been closely followed nor rigorously validated. Substantial advances have occurred regarding the appropriate quality and breadth of preclinical testing for candidate acute stroke therapies for better clinical translation. The updated STAIR preclinical recommendations reinforce the previous suggestions that reproducibly defining dose response and time windows with both histological and functional outcomes in multiple animal species with appropriate physiological monitoring is appropriate. The updated STAIR recommendations include: the fundamentals of good scientific inquiry should be followed by eliminating randomization and assessment bias, a priori defining inclusion/exclusion criteria, performing appropriate power and sample size calculations, and disclosing potential conflicts of interest. After initial evaluations in young, healthy male animals, further studies should be performed in females, aged animals, and animals with comorbid conditions such as hypertension, diabetes, and hypercholesterolemia. Another consideration is the use of clinically relevant biomarkers in animal studies. Although the recommendations cannot be validated until effective therapies based on them emerge from clinical trials, it is hoped that adherence to them might enhance the chances for success.
Construction of the RSS V3.2 Lower-Tropospheric Temperature Dataset from the MSU and AMSU Microwave Sounders
Authors: Mears Carl A. , Wentz Frank J.
Published: February 2009

Measurements made by microwave sounding instruments provide a multidecadal record of atmospheric temperature in several thick atmospheric layers. Satellite measurements began in late 1978 with the launch of the first Microwave Sounding Unit (MSU) and have continued to the present via the use of measurements from the follow-on series of instruments, the Advanced Microwave Sounding Unit (AMSU). The weighting function for MSU channel 2 is centered in the middle troposphere but contains significant weight in the lower stratosphere. To obtain an estimate of tropospheric temperature change that is free from stratospheric effects, a weighted average of MSU channel 2 measurements made at different local zenith angles is used to extrapolate the measurements toward the surface, which results in a measurement of changes in the lower troposphere. In this paper, a description is provided of methods that were used to extend the MSU method to the newer AMSU channel 5 measurements and to intercalibrate the results from the different types of satellites. Then, satellite measurements are compared to results from homogenized radiosonde datasets. The results are found to be in excellent agreement with the radiosonde results in the northern extratropics, where the majority of the radiosonde stations are located.
Corporate Social Responsibility and Broad-Based Black Economic Empowerment Legislation in South Africa
Authors: Arya Bindu , Bassi Balbir
Published: February 2009

The South African government has been active in promulgating specific corporate social responsibility (CSR) regulations since 1994 directed at the economic empowerment of historically disadvantaged Black people. Government laws have sought to involve corporations in promoting social cohesion and in addressing problems of historical exclusion of Black communities from the mainstream economy. This objective of transformation within the economy culminated in the release of the Broad-Based Black Economic Empowerment Act in 2003. The Department of Trade and Industry finalized the Codes of Good Practice on February 9, 2007, to clarify and ensure consistency in the implementation of socially responsible behavior in one area, empowerment of historically disadvantaged Black people (other areas of CSR do not display this consistently) within organizations across industry sectors. In this article, the authors discuss the key principles of this legislation, approaches to monitoring and measuring Codes of Good Practice implementation, and their implications for social-change initiatives in local and multinational enterprises that operate in South Africa.
Do Migrants Remit Democracy? International Migration, Political Beliefs, and Behavior in Mexico
Authors: Pérez-Armendáriz Clarisa , Crow David
Published: February 2009

International migrants are agents of democratic diffusion. They spread attitudes and behaviors absorbed in democratic host countries to their less democratic home countries by way of three processes: (a) migrant returns, (b) cross-border communication between migrants still abroad and their friends and family back home, and (c) migrant information networks in high-volume migration-producing communities. Marshaling data from an original June 2006 national survey in Mexico, the authors show that through one or another of these processes, migration alters the political participation and behavior of Mexicans living in Mexico.
The Impact of Security Placement on Female Offenders’ Institutional Behavior
Authors: Gobeil Renée , Blanchette Kelley , Barrett Meredith Robeson
Published: February 2009

It has been argued that institutional misconduct is promulgated by the correctional environments associated with different security levels. In this article, the authors summarize the results of a study examining whether such an association was present among Canadian federally sentenced female offenders. A total of 964 security reviews of federally sentenced women were analyzed to determine the independent effects of assessed risk (on the basis of individual-level factors) and security placement on institutional behavior. The analyses revealed that institutional behavior was related to assessed risk, after controlling for the effect of security placement. No relationship between security placement and misbehavior remained after controlling for assessed risk. Together, these findings suggest that although individual-level variables influence behavior, security placement does not.
Facilitating the Analysis of a UK National Blood Service Supply Chain Using Distributed Simulation
Authors: Mustafee Navonil , Taylor Simon J.E. , Katsaliaki Korina , Brailsford Sally
Published: February 2009

In an attempt to investigate blood unit ordering policies, researchers have created a discrete-event model of the UK National Blood Service (NBS) supply chain in the Southampton area of the UK. The model has been created using Simul8, a commercial off-the-shelf (COTS) discrete-event simulation package (CSP). However, as more hospitals were added to the model, it was discovered that the length of time needed to perform a single simulation severely increased. It has been claimed that distributed simulation, a technique that uses the resources of many computers to execute a simulation model, can reduce simulation runtime. Further, an emerging standardized approach exists that supports distributed simulation with CSPs. These CSP Interoperability (CSPI) standards are compatible with the IEEE 1516 standard, the High Level Architecture (HLA), the de facto interoperability standard for distributed simulation. To investigate if distributed simulation can reduce the execution time of NBS supply chain simulation, this paper presents experiences of creating a distributed version of the CSP Simul8 according to the CSPI/HLA standards. It shows that the distributed version of the simulation does indeed run faster when the model reaches a certain size. Further, we argue that understanding the relationship of model features is key to performance. This is illustrated by experimentation with two different protocols implementations (using Time Advance Request (TAR) and Next Event Request (NER)). Our contribution is therefore the demonstration that distributed simulation is a useful technique in the timely execution of supply chains of this type and that careful analysis of model features can further increase performance.
Optimal Sizing of a Stand-alone Wind/Photovoltaic Generation Unit using Particle Swarm Optimization
Authors: Ali Kashefi Kaviani  , Hamid Reza Baghaee  , Gholam Hossein Riahy
Published: February 2009

A hybrid wind/photovoltaic generation system is designed to supply power demand. The aim of this design is minimization of the overall cost of the generation scheme over 20 years of operation. Full demand supply is modeled as constraint for optimization problem. Characteristic equations of the system components and solar radiation and wind speed datasets are assumed to be deterministic, i.e. uncertainties are ignored. The system's costs include investment, replacement, and operation and maintenance costs during 20 years of system lifetime. All system components are commercially available, and actual prices are used. Wind and radiation datasets are for the North West region of Iran (Ardebil province). A Particle Swarm Optimization (PSO) algorithm is used to solve the optimization problem. Results indicate superiority of the PSO algorithm, in terms of speed and convergence to global optimum solution, over a Genetic Algorithm that is conventionally exploited in literature.
Anti-mite Covers: Potential Criteria for Materials Used Against Dust Mites
Authors: Mahakittikun Vanna , Boitano John Joseph , Komoltri Chulaluk , Ninsanit Prapakorn , Wangapai Teerapong
Published: February 2009

There are many types of material used to construct bedding encasing for dust mite and allergen protection, but relatively few have been evaluated for their anti-mite properties. This study surveyed the anti-mite/allergen properties and physical characteristics of covers with a view towards establishing potential parameters for evaluating the efficacy of such encasings. Fifty-three covers advertised as mite-proof were randomly purchased from local markets found in ten different countries. All fabrics were evaluated for their ability to block the movement of allergens and live mites. Air permeability, dust leakage, and thread count, where applicable, were also measured. The major finding was that plastic and the tightly woven covers completely prevented mite penetration while exhibiting > 99 % allergen impenetrability. The film-coated fabrics, the mixed type, and the acaricidal-coated non-woven were successful in blocking allergens, but were commonly observed to allow some mite penetration. For the tightly woven fabrics, dust leakage and air permeability were minimal, while thread count was uniformly high. Cotton bed sheets were completely penetrable by mites and allergens. Overall, allergen impenetrability was negatively associated with dust leakage, thread count, and air permeability. Thread count also exhibited inverse relationships between dust leakage and air permeability. Dust leakage and air permeability were positively associated. The optimal characteristics for effective encasings include tightly woven covers with allergen impenetrability > 99 %, resistance to live mite penetration, dust leakage of < 4 %, air permeability between 2 and 6 cm3/sec/cm 2, a thread count ≥ 246/in2, and a pore size of 2—10 µm.
Geometrical Models for Balanced Rib Knitted Fabrics Part I: Conventionally Knitted 1 × 1 Rib Fabrics
Authors: Kurbak Arif
Published: February 2009

The 1 × 1 rib knitted fabric is mostly used for collar, cuff, waistband, etc. of outerwear knitted garments and it is also very popular nowadays for using as preforms of knitted composite structures. A geometrical model to predict the dimensional properties of conventionally knitted 1 × 1 rib fabric is created and given in part I of this series of papers. With the 1 × 1 rib model, relaxation mechanism and the effect of tightness on conventionally knitted 1 × 1 rib fabrics of wool are attempted to be explained (as an example of application of the model).
Comparisons of Core—Sheath Structuring Effects on the Tensile Properties of High-Tenacity Ring Core-Spun Yarns
Authors: Yang Hee W. , Kim Hyung J. , Zhu Cheng Y. , You Huh
Published: February 2009

The structuring effects of the core and sheath on the tensile properties of core-spun yarns need to be systemized in order to meet potential application requirements. In this study, the core— sheath structuring effect was modeled theoretically, using a spring and damper as mechanical elements. Core-spun yarns with high tenacity filaments as the core and cotton staples as the sheath were prepared and tested to determine their tensile properties. Results demonstrated that the tensile system of the ring core-spun yarn could be described with four mechanical elements, two elements for the core-sheath geometry and two elements for the structuring effect. The core-spun yarns had a lower elastic modulus than the core filaments, and an easy viscous deformation of the core-spun yarn occurred with core spinning. Increasing the number of twists led to a consistent decrease in the strength of aramid core-spun yarn, while the high tenacity PET core-spun yarn had almost unaffected tenacity for various twist levels. The basalt core-spun yarn, however, demonstrated a twist factor level that indicated a potential maximum yarn tenacity. The breaking elongation of the aramid core-spun yarn had an increasing tendency with the number of twists. The high tenacity PET core-spun yarn remained in a limited range of elongation with twists. The basalt core-spun yarn had noticeably greater elongation as the number of twists increased.
No Dilemma for Pancritical Rationalism
Authors: Rowbottom Darrell P.
Published: February 2009

Hauptli (1991) presents a putative dilemma for Bartley’s (1984) pancritical rationalism that has remained unchallenged. This note sets the record straight by exposing two lacunae in Hauptli’s argument.
Turner on Merton
Authors: Agassi Joseph
Published: February 2009

Stephen Turner complains about weaknesses of Robert K. Merton's teachings without noticing that these are common. He puts down Merton's ideas despite his innovations, on the ground that they are not successful and not sufficiently revolutionary. The criteria by which he condemns Merton are too vague and too high. Merton's merit is in his having put the sociology of science on the map and drawn attention to the egalitarianism that was prominent in classical science and that is now diminished.
Lack of Interaction Between the Peptidomimetic Substrates Captopril and Cephradine
Authors: Foster David R. , Yee Shiyin , Bleske Barry E. , Carver Peggy L. , Shea Michael J. , Menon Sujatha S. , Ramachandran Chandrasekharan , Welage Lynda S. , Amidon Gordon L.
Published: February 2009

Intestinal peptide transporters, including hPEPT1, facilitate the absorption of cephalosporins and angiotensin‐converting enzyme inhibitors, and have been investigated as a means to improve oral drug absorption. Renal peptide transporters including hPEPT2, may also facilitate renal reabsorption of such compounds. In vitro and animal studies suggest that co‐administration of peptidomimetic compounds may alter oral pharmacokinetics, although this has not been well studied in humans. The purpose of this study was to determine whether co‐administration of the hPEPT substrates captopril and cephradine alters the oral pharmacokinetics of either agent. Nine healthy male volunteers received a single oral 25‐mg dose of captopril, a single oral 500‐mg dose of cephradine, or concurrent ingestion of captopril and cephradine in a cross‐over manner. Venous blood samples were taken and captopril and cephradine pharmacokinetics were determined using noncompartmental analyses. No significant differences were observed in captopril or cephradine pharmacokinetics when administered together as compared to each agent alone (a marginal decrease in Cmaxwas observed for both captopril and cephradine during co‐administration [5–15%]; however, differences were not statistically significant). The results of our study suggest that hPEPT1 and hPEPT2 are unlikely to contribute to clinically important drug interactions in humans.
Trial Treatment Length Optimization With an Emphasis on Disease Progression Studies
Authors: Hennig Stefanie , Nyberg Joakim , Hooker Andrew C. , Karlsson Mats O.
Published: February 2009

Optimal design has been used in the past mainly to optimize sampling schedules for clinical trials. Optimization on design variables other than sampling times has been published in the literature only once before. This study shows, as an example, optimization on the length of treatment periods to obtain reliable estimates of drug effects on long‐term disease progression studies. Disease progression studies are high in cost, effort, and time; therefore, optimization of treatment length is highly recommended to avoid failure or loss of information. Results are provided for different drug effects (eg, protective and symptomatic) and for different lengths of studies and sampling schedules. The merits of extending the total study length versus inclusion of more samples per participants are investigated. The authors demonstrate that if no observations are taken during the washout period, a trial can lose up to 40% of its efficiency. Furthermore, when optimization of treatment length is performed using multiple possible drug effect models simultaneously, these studies show high power in discriminating between different drug effect models.
Clopidogrel Resistance: Pharmacokinetic or Pharmacogenetic?
Authors: Ford Neville F.
Published: February 2009

Clopidogrel is important for the management of acute coronary syndromes and, along with aspirin, is recommended in the American College of Cardiology/American Heart Association guideline. It is also used along with aspirin, during the placement of coronary artery stents. Clopidogrel resistance was recognized in such procedures, as several patients did not have the anticipated platelet aggregation response to an ex vivo adenosine diphosphate challenge. From the EXCELSIOR study, which investigated the phenomenon, it was appreciated that it was present prior to treatment with clopidogrel and was therefore an intrinsic property of the patient's platelets. From other studies, it was appreciated that the patients who had clopidogrel resistance had a defective allele *2/ in the CYP2C19 gene. Furthermore, there was a dose response evident in that the homozygotes CYP2C19*2/*2 had platelets that responded even less well to clopidogrel than the heterozygotes CYP2C19*2 that responded less well than the wild‐type homozygote. The involvement of the phenomenon with CYP2C19 led some to believe that it was a pharmacokinetic issue. However, the major oxidative metabolic pathway for clopidogrel by which the reactive intermediate is formed is CYP3A4. It is suggested that there is a linkage between a polymorphism of the platelet receptor P2Y12 and the polymorphism of CYP2C19.