bluuebunny/crossref_metadata_2025 huggingface dataset:
Acid Production by Oral Strains of Candida albicans and Lactobacilli
Authors: Klinke T. , Kneist S. , de Soet J.J. , Kuhlisch E. , Mauersberger S. , Förster A. , Klimm W.
Published: February 2009

Both Candida albicans and lactobacilli are common colonizers of carious lesions in children and adolescents. The purpose of this study is to compare the velocity of acid production between C. albicans and several Lactobacillus species at different pH levels and concentrations of glucose. Washed, pure resting-cell suspensions were obtained by culturing a total of 28 oral isolates comprising the species C. albicans, Lactobacillus rhamnosus, Lactobacillus paracasei paracasei, Lactobacillus paracasei tolerans and Lactobacillus delbrueckii lactis. Acid production from glucose was determined at a constant pH of 7.0, 5.5, 5.0 and 4.0 by repeated titrations with NaOH in an automated pH-stat system. Acid formation rates of yeast and lactobacilli proved to be similar at both neutral and low pH, while in a moderately acidic environment C. albicans produced less acid than the lactobacilli. Ion chromatographic analysis of the cell-free medium after titration revealed pyruvate to be the predominant organic acid anion secreted by C. albicans. The proportion of organic acids to overall acid production by the yeast was below 10% at neutral conditions, in contrast to 42–66% at pH 4.0. Compared to lactobacilli, yeast required a concentration of glucose that was about 50 times higher to allow acid production at half the maximum speed. Considering the clinical data in the literature about the frequency and proportions of microorganisms present in early childhood caries lesions, the contribution of oral lactobacilli as well as C. albicans to overall microbial acid formation appears to be important.
Prevalence and Incidence of Multiple Sclerosis in Panama (2000–2005)
Authors: Gracia F. , Castillo L.C. , Benzadón A. , Larreategui M. , Villareal F. , Triana E. , Arango A.C. , Lee D. , Pascale J.M. , Gomez E. , Armien B.
Published: February 2009

Background: The first cases of multiple sclerosis (MS) in Panama were notified in the 1980s and it was considered a low-risk region for this disease. Between 2000 and 2005, a prevalence study was conducted to characterize MS in Panama. Methods: An instrument was developed to gather information from clinical files and interviews with previous informed consent. The diagnosis was confirmed by neurologists applying the Poser and McDonald criteria as per the inclusion period. Results: 178 patients from the public and private health sectors were captured between 1970 and 2005. The prevalence rate was 5.24/100,000 inhabitants, and the incidence was between 0.28 and 0.61/100,000 inhabitants. The disease was predominant among women, the mean age ± SD being 34.76 ± 10.909 years (1st crisis), and the average number of crises was 2.88. The most common clinical findings were motor, optic neuritis, sensitive and cerebellous. 52.4% presented monosymptomatic manifestations, 71.6% were clinically defined according to Poser’s criteria and 55.6% had MS according to McDonald’s criteria. 77.8% had their debut with the relapsing-remitting type and presented an Expanded Disability Status Scale score of 2.7 after the first crisis. Conclusion: MS is in Panama a neurological pathology with a low prevalence and the results of this investigation improved early treatment and diagnosis of this disease.
Dietary Total Fat Intake and Ischemic Stroke Risk: The Northern Manhattan Study
Authors: Boden-Albala Bernadette , Elkind Mitchell S.V. , White Halina , Szumski Annette , Paik Myunghee C. , Sacco Ralph L.
Published: February 2009

Background: Dietary fat intake is associated with coronary heart disease risk, but the relationship between fat intake and ischemic stroke risk remains unclear. We hypothesized that total dietary fat as part of a Western diet is associated with increased risk of ischemic stroke. Methods: As part of the prospective Northern Manhattan Study, 3,183 stroke-free community residents over 40 years of age underwent evaluation of their medical history and had their diet assessed by a food-frequency survey. Cox proportional hazard models calculated risk of incident ischemic stroke. Results: The mean age of participants was 69 years, 63% were women, 21% were white, 24% black and 52% Hispanic. During a mean of 5.5 years of follow-up, 142 ischemic strokes occurred. After adjusting for potential confounders, risk of ischemic stroke was higher in the upper quintile of total fat intake compared to the lowest quintile (HR 1.6, 95% CI 1.0–2.7). Total fat intake >65 g was associated with increased risk of ischemic stroke (HR 1.6, 95% CI 1.2–2.3). Risk was attenuated after controlling for caloric intake. Conclusions: The results suggest that increased daily total fat intake, especially above 65 g, significantly increases risk of ischemic stroke.
Telencephalic Organization in the Spotted African Lungfish, Protopterus dolloi: A New Cytological Model
Authors: Northcutt R. Glenn
Published: February 2009

Recent studies have greatly increased our knowledge of telencephalic organization in ray-finned fishes and terrestrial vertebrates, particularly amphibians. In contrast, little new information has been generated on telencephalic organization in lobe-finned fishes. The coelacanth, Latimeria, and three genera of lungfishes constitute the living lobe-finned fishes. Latimeria is extremely rare and critically endangered, so the living lungfishes, therefore, offer the only feasible source of new information on telencephalic organization in lobe-finned fishes. A re-examination of the cytoarchitectonics of the telencephalon in the Spotted African Lungfish has allowed the generation of a new model of telencephalic organization in lungfishes. To begin to test this model, examination was made of the telencephalic distribution of acetylcholinesterase, enkephalin, the neurotensin-related hexapeptide LANT6, nitric oxide synthase (nicotinamide adenine dinucleotide phosphate-diaphorase), substance P, and tyrosine hydroxylase. This distribution supports the new model and suggests that the medial pallial-subpallial border, the striatopallidal systems, and the amygdalar organization in this lungfish are more similar to these features in terrestrial vertebrates than was previously suspected.
Quality of Life in Patients with Laryngopharyngeal Reflux
Authors: Cheung Ting Kin , Lam Paul K.Y. , Wei William Ignace , Wong Wai Man , Ng Manwa L. , Gu Qing , Hung Ivan F. , Wong Benjamin C.Y.
Published: February 2009

Background: Laryngopharyngeal reflux (LPR) disease is an extraesophageal manifestation of gastroesophageal reflux disease (GERD). The impact of GERD-related LPR on the psychological well-being and quality of life (QOL) in Chinese is not known. Aim: To assess the QOL in patients with LPR disease. Methods: 76 LPR and 73 healthy subjects were recruited. Psychological well-being was assessed by the Hospital Anxiety and Depression Score and QOL was assessed by SF-36. Results: 51/76 (67.1%) patients had GERD-related LPR. More LPR subjects had taken sick leave (36.2 vs. 5.6%, p = 0.001) and reported adverse social life impact (60.5 vs. 38.9%, p = 0.013). LPR patients showed significantly worse results on the Voice Handicap Index (47.8 vs. 7.6, p = 0.001), were more anxious and had worse QOL in social functioning, pain and general health perception domains of SF-36. GERD-related LPR subjects had a higher depression score (4.8 vs. 3.8, p = 0.014) and a lower mental summary score (41.8 vs. 48.4, p = 0.01) in SF-36 compared with those without GERD. Conclusions: LPR had a negative impact on psychological status, social functioning and QOL. GERD symptoms appeared to be the main contributor to decrease QOL. GERD-related LPR patients had a significant impact on the mental component of their QOL.
Thiopurine Methyltransferase Gene Polymorphisms in Chinese Patients with Inflammatory Bowel Disease
Authors: Cao Qian , Zhu Qin , Shang Yan , Gao Min , Si Jianmin
Published: February 2009

Background: The thiopurine drugs azathioprine and 6-mercaptopurine are well established in the treatment of inflammatory bowel disease (IBD). However, great interpatient variability exists in the efficacy and toxicity of the drugs, and this results from thiopurine methyltransferase (TPMT) gene polymorphisms. The aim of this study was to identify the TPMT gene polymorphisms in Chinese IBD patients and to study the relationship between TPMT status and thiopurine-related toxicity in these patients. Materials and Methods: A total of 189 IBD patients, 87 with Crohn’s disease and 102 with ulcerative colitis, and 273 healthy controls were enrolled. All subjects were from the Han Chinese ethnic group. Polymorphisms in TPMT*2, *3A, *3B and *3C were analyzed using allele-specific polymerase chain reaction and polymerase chain reaction-restriction fragment length polymorphism. Direct sequencing was used to confirm the mutation results. Exons of the TPMT gene from patients who suffered from azathioprine-induced toxicity were amplified and sequenced to detect TPMT mutations. Results: No TPMT*2, *3A or *3B mutant alleles were detected. The allele frequency of TPMT*3C in the IBD group was 1.59%, which was similar to that of the healthy control group (1.59 vs. 1.47%, p = 1.000). Forty-three patients were treated with azathioprine therapy, 4 experienced myelotoxicity, and 1 experienced hepatotoxicity, so the incidence of drug toxicity was 11.7% (5/43). No TPMT*2, *3A, *3B or *3C polymorphisms were detected in these 5 patients. After directly sequencing the exons of the TPMT gene in these 5 patients, a synonymous single-nucleotide polymorphism (TPMT*1S), which does not alter the encoded amino acid, was found in 3 patients. Conclusion: TPMT*3C seemed to be a unique variant allele in this Han Chinese population. The overall frequencies of variant TPMT alleles in this population were lower than those in Caucasians, but thiopurinetoxicity in Han Chinese IBD patients is not low. Factors other than TPMT polymorphisms may be responsible for the development of toxicity.
Impact of Fruit Beverage Consumption on the Antioxidant Status in Healthy Women
Authors: Cilla Antonio , De Palma Giada , Lagarda María J. , Barberá Reyes , Farré Rosaura , Clemente Gonzalo , Romero Fernando
Published: February 2009

Background: Epidemiologic studies suggest that antioxidant-rich foods might reduce the risk of cancer and cardiovascular diseases. Aim: To test the health-protective potential of three fruit beverages, Fb (grape-orange-apricot), FbM (Fb with skimmed milk) and FbMFe [FbM + Fe(II)], in healthy women. Methods: The influence of fruit beverage consumption (500 ml/day) upon serum antioxidant capacity determined by ORAC and TEAC methods and erythrocyte superoxide dismutase (SOD) activity was assessed in 32 healthy female volunteers. In the intervention study, each subject received the fruit beverages during three periods (3 weeks for Fb and FbM, and 12 weeks in the case of FbMFe), with a 2-week washout period between treatments. Results: Intake of fruit beverages does not improve total antioxidant capacity. However, the induction of SOD found after fruit beverage consumption may be more effective than the effects of antioxidants present in these beverages, which can only stoichiometrically scavenge reactive species derived from oxidative stress. Conclusion: Iron added to FbM (FbMFe) showed induction of SOD activity, with no prooxidant effect, and could constitute a complementary source of iron, because the regular consumption of FbMFe may be beneficial for women of fertile age.
Modulation of Growth Hormone and Prolactin Secretion in Trypanosoma cruzi-Infected Mammosomatotrophic Cells
Authors: Corrêa-de-Santana Eliane , Paez-Pereda Marcelo , Theodoropoulou Marily , Renner Ulrich , Stalla Johanna , Stalla Günter Karl , Savino Wilson
Published: February 2009

Objective: In a previous study, we reported an imbalance in the hypothalamus-pituitary-adrenal axis of mice acutely infected with the protozoan parasite Trypanosoma cruzi, the causative agent of Chagas disease. Methods: Possible effects of this parasitic infection on the endocrine function of other pituitary cell types were studied, in particular regarding the production of prolactin (PRL) and growth hormone (GH). Results: In the mammosomatotrophic cell line GH3, both GH and PRL secretion were decreased, reflecting the diminished PRL concentrations in the pituitary glands of infected mice. Additionally, expression of extracellular matrix proteins, e.g. laminin, was increased in T. cruzi-infected GH3 cells, which may be related to the diminished secretory function of these cells. Lastly, the expression of Pit-1, a major transcription factor for the PRL and GH genes, is also decreased in T. cruzi-infected cultures. Conclusion: T. cruzi infection downregulates PRL and GH production. Combined with our previous data showing increased glucocorticoid levels following T. cruzi infection, the immunosuppression induced by T. cruzi infection may be partially related to multiple endocrine changes involving the hypothalamus-pituitary axis and corresponding target endocrine glands.
Differential Affection of Intestinal Immune Cell Populations after Cerebral Ischemia in Mice
Authors: Schulte-Herbrüggen Olaf , Quarcoo David , Meisel Andreas , Meisel Christian
Published: February 2009

Background/Aims: Infections cause a major clinical problem within the first days after cerebral stroke. In a mouse model we have recently demonstrated that stroke leads to immunodepression facilitating spontaneous bacterial pneumonia and bacteremia. So far, it has been unknown whether poststroke immunomodulation impairs local intestinal immune populations which may promote gut barrier dysfunction leading to translocation of intestinal microorganisms and microbial products. In this study, we investigated changes in intestinal intraepithelial, lamina propria and Peyer’s patch immune cell populations after experimental stroke. Methods: 129SV mice were subjected to experimental stroke by filament occlusion of the middle cerebral artery or sham operation. After 24 h, animals were sacrificed, and intraepithelial lymphocytes, lamina propria lymphocytes and Peyer’s patches were isolated and leukocyte subpopulations analyzed by flow cytometry. Results: Peyer’s patches revealed a significant reduction of T and B cell counts after cerebral ischemia, while no differences in natural killer cells and macrophages were observed. In contrast, no significant changes in intraepithelial and lamina propria lymphocyte subsets were observed in middle cerebral artery animals compared to controls. Conclusion: Cerebral ischemia has differential effects on cellularity of gut-associated lymphoid tissue. Further studies on the mechanisms involved in quantitative changes of gut immune cells as well as on the function of these cells are needed to better understand the consequences of stroke-induced alterations of the local intestinal immune compartment for the enhanced susceptibility to infections after stroke.
Nutritional State during COPD Exacerbation: Clinical and Prognostic Implications
Authors: Girón R. , Matesanz C. , García-Río F. , de Santiago E. , Mancha A. , Rodríguez-Salvanés F. , Ancochea J.
Published: February 2009

Aims: To estimate the prevalence of malnutrition in chronic obstructive pulmonary disease (COPD) patients hospitalized for exacerbation and to evaluate its clinical and prognostic influence on the exacerbation. Subjects/Methods: The subjects were 78 consecutive patients with moderate-to-severe COPD who were admitted to hospital with a diagnosis of exacerbation. Nutritional status was assessed by means of body mass index (BMI), bioelectric impedance analysis and levels of plasmatic albumin. Previous spirometry, 6-min walk test, severity of the exacerbation, days of hospitalization and readmission in the following 3 months were also evaluated. Results: Malnutrition [BMI <20 or fat-free mass (FFM) index ≤16] occurred in 38% of patients, while in 40% the involuntary weight loss revealed a malnutrition risk and in 18% patients the plasmatic albumin levels were <3 g/dl. FFM was correlated with forced expiratory volume in 1 s, forced vital capacity and distance walked in 6 min. Number of days of hospitalization were related to FFM, muscle mass, BMI and albumin. The patients readmitted in the following 3 months had less FFM than the patients who were not readmitted. Conclusions: The high prevalence of malnutrition among hospitalized COPD patients is related to their lung function and exercise tolerance. Moreover, nutritional parameters during exacerbation are related to length of hospitalization and readmission.
Role of Translocation of Pathogen-Associated Molecular Patterns in Sepsis
Authors: Tsujimoto Hironori , Ono Satoshi , Mochizuki Hidetaka
Published: February 2009

Background/Aim: Unlike animals, the incidence of bacterial translocation and its clinical significance remain to be determined in humans, which may be due to the lack of accurate methods to confirm and monitor bacterial translocation. The literature on the consequences of novel insights of bacterial translocation was reviewed. Methods: The Medline databases were searched for publications regarding translocation of bacteria as well as pathogen-associated molecular patterns. Results: Although substantial data support the occurrence of bacterial translocation in humans, the lack of data correlating bacterial translocation with its clinical significance has lead to confusion among physicians. Toll-like receptors have been implicated in the mediation of systemic responses to the relevant pathogen-associated molecular pattern. The gut is a reservoir of pathogen-associated molecular patterns from microbes, and translocation of pathogen-associated molecular patterns other than endotoxin also induces a systemic inflammatory response through toll-like receptors. Conclusions: Pathogen-associated molecular patterns translocation may be at least partly responsible for the development of sepsis under conditions in which bacterial translocation may occur. Detection of bacterial DNA in blood and tissues/organs should be useful as a marker of translocation of pathogen-associated molecular patterns and/or bacterial translocation, and should have the predictive value for developing sepsis in surgical patients.
Will Knowledge of Gene-Based Colorectal Cancer Disease Risk Influence Quality of Life and Screening Behavior?
Authors: Ramsey Scott , Blough David , McDermott Cara , Clarke Lauren , Bennett Robin , Burke Wylie , Newcomb Polly
Published: February 2009

Background: Several gene variants conveying a modestly increased risk for disease have been described for colorectal cancer. Patient acceptance of gene variant testing in clinical practice is not known. We evaluated the potential impact of hypothetical colorectal-cancer-associated gene variant testing on quality of life, health habits and cancer screening behavior. Methods: First-degree relatives of colorectal cancer patients and controls from the Seattle Colorectal Cancer Familial Registry were invited to participate in a web-based survey regarding testing for gene variants associated with colorectal cancer risk. Results: 310 relatives and 170 controls completed the questionnaire. Quality of life for the hypothetical carrier state was modestly and nonsignificantly lower than current health after adjustment for sociodemographic and health factors. In the positive test scenario, 30% of respondents expressed willingness to change their diet, 25% to increase exercise, and 43% to start colorectal cancer screening. The proportions willing to modify these habits did not differ between groups. Conclusions: Testing for gene variants associated with colorectal cancer risk may not influence quality of life, but may impact health habits and screening adherence. Changing behaviors as a result of testing may help to reduce cancer incidence and mortality, particularly among those at higher risk for colorectal cancer.
Home Blood Pressure Measurements for Managing Hypertension in Hemodialysis Patients
Authors: Agarwal Rajiv , Satyan Sangeetha , Alborzi Pooneh , Light Robert P. , Tegegne Getachew G. , Mazengia Helmneh S. , Yigazu Paulos M.
Published: February 2009

Home blood pressure (BP) monitoring serves as a practical method to detect changes in BP instead of ambulatory BP monitoring in hemodialysis patients. To evaluate the relationship of reduction in home BP compared to interdialytic ambulatory BP measurements we analyzed the data from the dry-weight reduction in hypertensive hemodialysis patients (DRIP) trial in which 100 patients had their dry weight probed based on clinical sign and symptoms and 50 patients served as controls. We measured home BP 3 times a day for 1 week using a validated oscillometric monitor on 3 occasions at 4-week intervals after randomization. Changes from baseline in home, predialysis BP and postdialysis BP were compared to interdialytic 44-hour ambulatory BP. Home and ambulatory BP monitoring was available in 141 of 150 (94%) patients. Predialysis systolic BP was not as sensitive as ambulatory BP in detecting change in BP with dry-weight reduction. Whereas postdialysis BP was capable of detecting an improvement in systolic BP in response to probing dry weight, by itself it does not provide evidence that change in postdialysis BP persists over the interdialytic period. Home BP reliably detected changes in ambulatory BP, albeit with less sensitivity at 4 weeks. However, at 4 and at 8 weeks, changes in home systolic BP were most strongly related to changes in interdialytic ambulatory systolic BP compared to predialysis and postdialysis BP. The reproducibility of BP measurements followed the order home > ambulatory >> predialysis > postdialysis. These data provide support for the use of home BP monitoring for the management of hypertension in hemodialysis patients.
Regulation of Extracellular Chromatin Release from Neutrophils
Authors: Neeli Indira , Dwivedi Nishant , Khan Salar , Radic Marko
Published: February 2009

Neutrophils use intricate mechanisms for capturing and killing invading microorganisms. One mechanism entails the release of relaxed chromatin from the cell. Microbes are trapped by the extracellular chromatin and exposed to high local concentrations of bactericidal compounds. We examine the regulation of chromatin release by testing the contribution of microtubules and the actin cytoskeleton to the deployment of neutrophil extracellular traps (NETs). Incubation of human neutrophils with nocodazole, a tubulin polymerization inhibitor, or cytochalasin D, an inhibitor of actin filamentation, severely diminished the ability of neutrophils to respond to LPS by releasing chromatin from the cells. In addition, pretreatment of neutrophils with M1/70, a monoclonal antibody to the Mac-1 integrin adhesion receptor, drastically reduced the deployment of chromatin into NETs. Analysis of histone deimination, the conversion of arginine to citrulline in 3 of the 4 core histones by peptidylarginine deiminase 4, revealed that the treatments inhibiting NET formation also reduced histone deimination. Our data indicate that NET formation requires functional tubulin and actin filaments and responds to engagement of Mac-1 integrins. Because histone deimination coincides with the release of NETs, we propose that these events represent overlapping mechanisms of neutrophil responses to infections.
Apoptotic Functions of
PDCD10/CCM3
, the Gene Mutated in Cerebral Cavernous Malformation 3
Authors: Chen Leiling , Tanriover Gamze , Yano Hiroko , Friedlander Robert , Louvi Angeliki , Gunel Murat
Published: February 2009

Background and Purpose—

Mutations in the
Programmed Cell Death 10
(
PDCD10
) gene cause autosomal dominant familial cerebral cavernous malformations (CCM3). To date, little is known about the function of this gene and its role in disease pathogenesis.

Methods—

We examined the effects of overexpression of wild-type and 2 human disease-causing variants of
PDCD10
on cell death using 3 different methods (TUNEL and MTT assays and caspase-3 activation). We analyzed expression of CCM3, activated caspase-3, and p38 in endothelial cell lines using the serum deprivation model of apoptosis induction. Finally, we assayed the effects of siRNA-mediated inhibition of endogenous
PDCD10
expression on cell death in endothelial cell cultures.

Results—

Overexpression of wild-type CCM3, but not disease-linked mutant forms, induced apoptosis as confirmed by TUNEL and increased levels of activated caspase-3. Serum starvation of endothelial cells, an inducer of apoptosis, led to increased expression of CCM3 and activation of p38 and ultimately activated caspase-3. siRNA-mediated inhibition of CCM3 expression resulted in decreased levels of p38 and activated caspase-3, and decreased cell death.

Conclusions—

CCM3 is both necessary and sufficient to induce apoptosis in vitro in well-defined cell culture systems. Even though it is currently unclear whether this effect on apoptosis is direct or indirect through modulation of cell cycle, these results led to the novel hypothesis that CCM lesions may form as a consequence of aberrant apoptosis, potentially altering the balance between the endothelium and neural cells within the neurovascular unit.
Lack of Association Between Variations of
PDE4D
and Ischemic Stroke in the Japanese Population
Authors: Matsushita Tomonaga , Kubo Michiaki , Yonemoto Koji , Ninomiya Toshiharu , Ashikawa Kyota , Liang Bailing , Hata Jun , Doi Yasufumi , Kitazono Takanari , Ibayashi Setsuro , Iida Mitsuo , Kiyohara Yutaka , Nakamura Yusuke
Published: February 2009

Background and Purpose—

After the first genomewide association study of ischemic stroke identified
PDE4D
as a susceptible gene, many replication studies have been conducted. However, the validity of the association has remained controversial because of the heterogeneity of both genetic markers and phenotypes.

Methods—

We investigated the association between variations of
PDE4D
and ischemic stroke by 3 methods: single-marker, haplotype, and tag-single nucleotide polymorphism (SNP) analyses. In the single-marker analysis, we evaluated the association using 2 large case–control samples (1112 cases and 1112 control subjects in a sample obtained from Kyushu, Japan, and 1711 cases and 1786 control subjects in BioBank Japan) and a prospective cohort with 14 years of follow-up. These samples were analyzed both separately and pooled. Haplotype and tag-SNP analyses were performed using the 2 case–control samples together.

Results—

In single-marker association tests, we found no significant association in the same direction among the 6 SNP reported in the initial study and ischemic stroke subtypes. Haplotype analysis revealed no significant association between the region around the 5′-end of the gene and combined atherothrombotic and cardioembolic infarction. Rs7730070, a SNP located around the 3′-end of
PDE4D
, showed the lowest nominal probability value by tag-SNP analysis but was not significant after adjustment for multiple testing (adjusted probability value =0.36).

Conclusions—

These results suggest that variations in
PDE4D
are not associated with ischemic stroke risk in the Japanese population.
Angiotensin AT
2
Receptor Stimulation Causes Neuroprotection in a Conscious Rat Model of Stroke
Authors: McCarthy Claudia A. , Vinh Antony , Callaway Jennifer K. , Widdop Robert E.
Published: February 2009

Background and Purpose—

The angiotensin II type 2 receptor (AT
2
R) is implicated to be neuroprotective in stroke, although this premise has not been directly tested. Therefore, we have examined the neuroprotective effect of AT
2
R stimulation after intracerebroventricular administration of AT
2
R agonist CGP42112 in a conscious rat model of stroke.

Methods—

Spontaneously hypertensive rats were treated with either CGP42112 (0.1 to 10 ng/kg/min intracerebroventricularly) alone or in combination with the AT
2
R antagonist PD123319 (36 ng/kg/min intracerebroventricularly) beginning 5 days before stroke induction. A focal reperfusion model of stroke was induced in conscious spontaneously hypertensive rats by administering endothelin-1 to the middle cerebral artery through a surgically implanted cannula. Behavioral tests were used to assess the severity of neurological deficit as a result of the ischemic event. Cortical and striatal infarct volumes were measured 72 hours poststroke.

Results—

Blood pressure was unaffected by treatments. CGP42112 dose-dependently reduced cortical infarct volume poststroke, and PD123319 abolished the neuroprotective effect of CGP42112. PD123319 had no effect on infarct volume alone. These results were consistent with the behavioral findings, indicating that CGP42112 reduced motor deficit on the ledged beam test at 72 hours poststroke and immunohistochemical analyses showing that CGP42112 increased neuronal survival and minimized the loss of AT
2
R expression in the infarcted region.

Conclusion—

Based on infarct, behavioral, and immunohistochemical data, these results indicate that centrally administered CGP42112 exhibits a neuroprotective effect, which was independent of blood pressure. Thus, for the first time, we have shown that central AT
2
R stimulation is neuroprotective in a conscious rat model of stroke.
MRI Mismatch–Based Intravenous Thrombolysis for Isolated Cerebellar Infarction
Authors: Köhrmann Martin , Sauer Roland , Huttner Hagen B. , Engelhorn Tobias , Doerfler Arnd , Schellinger Peter D.
Published: February 2009

Background and Purpose—

Cerebellar infarctions constitute a significant proportion of ischemic strokes and carry a substantial morbidity and mortality mainly because of swelling in the posterior fossa. No specific acute therapy is established, and patients are usually excluded from intravenous thrombolysis (IVT).

Methods—

Two patients presented in an extended time window of 5 and 7 hours to our emergency department with sudden onset of severe cerebellar symptoms. After emergency MRI demonstrated superior cerebellar artery (SCA) occlusion with hypoperfusion of the respective territory and only minor DWI lesions, IVT was administered. Both patients recovered within a few hours after therapy and follow-up MRI on day 1 after treatment demonstrated only minor infarction.

Conclusion—

We present to our knowledge the first cases of MRI mismatch–based IVT in an extended time window in patients with isolated SCA-infarctions. More studies are needed to evaluate IVT in this patient population. Modern imaging techniques might be helpful to select patients for therapy in posterior circulation strokes.
Vascular Structure and Function Is Correlated to Cognitive Performance and White Matter Hyperintensities in Older Hypertensive Patients With Subjective Memory Complaints
Authors: Kearney-Schwartz Anna , Rossignol Patrick , Bracard Serge , Felblinger Jacques , Fay Renaud , Boivin Jean-Marc , Lecompte Thomas , Lacolley Patrick , Benetos Athanase , Zannad Faiez
Published: February 2009

Background and Purpose—

Arterial stiffening and thickening and endothelial dysfunction may be associated with cognitive decline or white matter hyperintensities (WMH) independently of blood pressure level. We aimed to investigate, using an integrative approach, the relative contributions of structural and functional vascular factors to the degree of cognitive impairment (primary outcome) and the severity of WMH (secondary outcome) in elderly hypertensive patients with subjective memory complaints, a group prone to dementia.

Methods—

A prospective, dedicated, cross-sectional population of 198 elderly hypertensive patients (mean age 69.3±6.2 years) with subjective memory complaints underwent a full set of cognitive function assessments, brain MRI with semiquantification of WMH, carotid ultrasonography, carotid–femoral pulse wave velocity, brachial endothelial function, and plasma von Willebrand Factor measurements.

Results—

After adjustment for the usual cardiovascular risk factors, increased arterial stiffness (as assessed by pulse wave velocity) was significantly and independently associated with memory impairment in men. The severity of WMH was independently associated with increased carotid intima media thickness and stiffness (as assessed by augmentation index) as well as with increased age and plasma levels of von Willebrand Factor, a biomarker of endothelial dysfunction.

Conclusions—

Our data suggest that vascular abnormalities, independently of blood pressure levels, may play a role in the setting of subjective memory complaints as well as of WMH in elderly hypertensive patients. Arterial thickness and stiffness as well as endothelial function should be assessed simultaneously and may represent additional targets for the prevention of subjective memory complaints and WMH.
Additional Stroke-Related and Non–Stroke-Related Cardiovascular Costs and Hospitalizations in Managed-Care Patients After Ischemic Stroke
Authors: Roberts Craig S. , Gorelick Philip B. , Ye Xin , Harley Carolyn , Goldberg George A.
Published: February 2009

Background and Purpose—

Prior stroke confers an increased risk of future cardiovascular events. Because the incremental economic impact of this added risk is unknown, we assessed the additional cardiovascular costs and hospitalizations associated with ischemic stroke.

Methods—

Patients hospitalized for ischemic stroke during 2002 to 2005 were identified from a large US managed-care plan and matched to control patients hospitalized for a noncardiovascular acute event. Cumulative stroke-related and non–stroke-related cardiovascular medical costs were determined for each group. Stroke and nonstroke cardiovascular hospitalization rates were calculated with the Kaplan–Meier method; risk of hospitalization was estimated with a Cox regression model.

Results—

Stroke patients and matched controls (N=11 883) were identified (mean age ≈58 years; 47.8% female). Compared with controls, patients hospitalized for ischemic stroke had higher stroke and nonstroke cardiovascular medical costs at 6 months (stroke: $1756 vs $50,
P
<0.01; nonstroke cardiovascular: $1437 vs $658,
P
<0.01) and 12 months (stroke: $2109 vs $68,
P
<0.01; nonstroke cardiovascular: $2203 vs $1167,
P
<0.01) of follow-up. Among stroke patients, cumulative stroke and nonstroke cardiovascular hospitalization rates were 9.06% and 5.63% at 6 months, respectively, and 21.09% and 22.05% at 36 months, respectively. Stroke patients were at significantly increased risk of repeat stroke hospitalization (hazard ratio=12.55; 95% CI, 10.50 to 15.01) and nonstroke cardiovascular hospitalization (hazard ratio=1.95; 95% CI, 1.77 to 2.14).

Conclusions—

After ischemic stroke, patients have significantly greater stroke and nonstroke cardiovascular costs and hospitalizations than do matched controls. Attention to total cardiovascular risk reduction in this population could potentially reduce downstream costs.
Clinical Evidence That Very Small Embryonic-Like Stem Cells Are Mobilized Into Peripheral Blood in Patients After Stroke
Authors: Paczkowska Edyta , Kucia Magda , Koziarska Dorota , Halasa Maciej , Safranow Krzysztof , Masiuk Marek , Karbicka Anna , Nowik Marta , Nowacki Przemyslaw , Ratajczak Mariusz Z. , Machaliński Boguslaw
Published: February 2009

Background and Purpose—

In a murine model of stroke, we identified a population of very small embryonic-like (VSEL) stem cells (SCs) in adult murine bone marrow that could be mobilized into peripheral blood (PB). This raised the question of whether a similar population of cells is mobilized in human stroke patients.

Methods—

We evaluated a number of cells that corresponded to VSEL SCs in the PB of 44 stroke patients and 22 age-matched controls. After each patient’s stroke, PB samples were harvested during the first 24 hours, on day +3, and on day +7 and then compared with normal controls. The circulating human cells with the phenotype of VSEL SCs were evaluated in PB by real-time quantitative polymerase chain reaction, fluorescence-activated cell sorting analysis, and direct immunofluorescence staining. In parallel, we also measured the serum concentration of stromal derived factor-1 by ELISA.

Results—

In stroke patients, we found an increase in the number of circulating cells expressing SC-associated antigens, such as CD133, CD34, and CXCR4. More important, we found an increase in the number of circulating primitive cells expressing the VSEL phenotype (CXCR4
+
lin
−
CD45
−
small cells), mRNA for Octamer-4 and Nanog, and Octamer-4 protein. All changes were accompanied by an increased serum concentration of stromal derived factor-1. Additionally, we found a positive correlation between stroke extensiveness, stromal derived factor-1 concentration in serum, and the number of CXCR4
+
VSEL SCs circulating in the PB.

Conclusions—

We conclude that stroke triggers the mobilization of CXCR4
+
VSEL SCs that have potential prognostic value in stroke patients. However, the potential role of these mobilized cells in brain regeneration requires further study.
Mechanisms of C-Reactive Protein-Induced Blood–Brain Barrier Disruption
Authors: Kuhlmann Christoph R.W. , Librizzi Laura , Closhen Dorothea , Pflanzner Thorsten , Lessmann Volkmar , Pietrzik Claus U. , de Curtis Marco , Luhmann Heiko J.
Published: February 2009

Background and Purpose—

Increased mortality after stroke is associated with brain edema formation and high plasma levels of the acute phase reactant C-reactive protein (CRP). The aim of this study was to examine whether CRP directly affects blood–brain barrier stability and to analyze the underlying signaling pathways.

Methods—

We used a cell coculture model of the blood–brain barrier and the guinea pig isolated whole brain preparation.

Results—

We could show that CRP at clinically relevant concentrations (10 to 20 μg/mL) causes a disruption of the blood–brain barrier in both approaches. The results of our study further demonstrate CRP-induced activation of surface Fcγ receptors CD16/32 followed by p38-mitogen-activated protein kinase-dependent reactive oxygen species formation by the NAD(P)H-oxidase. The resulting oxidative stress increased myosin light chain kinase activity leading to an activation of the contractile machinery. Blocking myosin light chain phosphorylation prevented the CRP-induced blood–brain barrier breakdown and the disruption of tight junctions.

Conclusions—

Our data identify a previously unrecognized mechanism linking CRP and brain edema formation and present a signaling pathway that offers new sites of therapeutic intervention.
Validation of a Large-Scale Simulated Brightness Temperature Dataset Using SEVIRI Satellite Observations
Authors: Otkin Jason A. , Greenwald Thomas J. , Sieglaff Justin , Huang Hung-Lung
Published: February 2009

In this study, the accuracy of a simulated infrared brightness temperature dataset derived from a unique large-scale, high-resolution Weather Research and Forecasting (WRF) Model simulation is evaluated through a comparison with Spinning Enhanced Visible and Infrared Imager (SEVIRI) observations. Overall, the analysis revealed that the simulated brightness temperatures realistically depict many of the observed features, although several large discrepancies were also identified. The similar shapes of the simulated and observed probability distributions calculated for each infrared band indicate that the model simulation realistically depicted the cloud morphology and relative proportion of clear and cloudy pixels. A traditional error analysis showed that the largest model errors occurred over central Africa because of a general mismatch in the locations of deep tropical convection and intervening regions of clear skies and low-level cloud cover. A detailed inspection of instantaneous brightness temperature difference (BTD) imagery showed that the modeling system realistically depicted the radiative properties associated with various cloud types. For instance, thin cirrus clouds along the edges of deep tropical convection and within midlatitude cloud shields were characterized by much larger 10.8 − 12.0-μm BTD than optically thicker clouds. Simulated ice clouds were effectively discriminated from liquid clouds and clear pixels by the close relationship between positive 8.7 − 10.8-μm BTD and the coldest 10.8-μm brightness temperatures. Comparison of the simulated and observed BTD probability distributions revealed that the liquid and mixed-phase cloud-top properties were consistent with the observations, whereas the narrower BTD distributions for the colder 10.8-μm brightness temperatures indicated that the microphysics scheme was unable to simulate the full dynamic range of ice clouds.
Convectively Coupled Waves Propagating along an Equatorial ITCZ
Authors: Dias Juliana , Pauluis Olivier
Published: February 2009

The dynamics of convectively coupled gravity waves traveling over a precipitating region are analyzed in an idealized model for the large-scale atmospheric circulation. The model is composed of a shallow water system coupled to an advection equation for moisture through the convection term, utilizing a quasi-equilibrium relaxation to moisture closure. Here the authors investigate the model in the strict quasi-equilibrium (SQE) of infinitely short relaxation time. This framework is applied to study the behavior of a disturbance propagating along a narrow precipitation band, similar to the intertropical convergence zone (ITCZ). For an ITCZ width on the order of the equatorial Rossby radius, Kelvin waves propagate at the moist gravity wave speed (about 15 m s−1), whereas for a narrow ITCZ, the propagation speed is comparable to the dry gravity wave (about 50 m s−1). It is also shown that a Kelvin wave propagating along a narrow precipitation region exhibits a meridional circulation that modulates the precipitation rate and affects the propagation speed of the wave.
On the Source of Mediterranean Overflow Water Property Changes
Authors: Lozier M. Susan , Sindlinger Laurie
Published: February 2009

A recent study of the eastern North Atlantic detailed significant increases in the temperature and salinity of the Mediterranean Overflow Water (MOW) from 1950 to 2000. To examine the degree to which the source waters, which spill over the sill at the Strait of Gibraltar, could be responsible for these observations in the open Atlantic, a box model of water mass transformation by marginal seas was employed. Time series for the salinity of the inflowing North Atlantic surface waters, freshwater fluxes in the Mediterranean (evaporation and precipitation and river runoff), and the volumetric flow rates for the inflow and outflow across the Strait of Gibraltar were used to predict the salinity of the source waters to the North Atlantic from 1950 to 2000. Results from this calculation reveal that source water changes have minimal impact on MOW property changes on interannual and decadal time scales. It is suggested instead that circulation changes within the open Atlantic alter the advective–diffusive pathways of MOW such that property changes within the MOW reservoir are created.
The Surprising Role of Orography in the Initiation of an Isolated Thunderstorm in Southern England
Authors: Lean Humphrey W. , Roberts Nigel M. , Clark Peter A. , Morcrette Cyril
Published: February 2009

Many factors, both mesoscale and larger scale, often come together in order for a particular convective initiation to take place. The authors describe a modeling study of a case from the Convective Storms Initiation Project (CSIP) in which a single thunderstorm formed behind a front in the southern United Kingdom. The key features of the case were a tongue of low-level high θw air associated with a forward-sloping split front (overrunning lower θw air above), a convergence line, and a “lid” of high static stability air, which the shower was initially constrained below but later broke through. In this paper, the authors analyze the initiation of the storm, which can be traced back to a region of high ground (Dartmoor) at around 0700 UTC, in more detail using model sensitivity studies with the Met Office Unified Model (MetUM). It is established that the convergence line was initially caused by roughness effects but had a significant thermal component later. Dartmoor had a key role in the development of the thunderstorm. A period of asymmetric flow over the high ground, with stronger low-level descent in the lee, led to a hole in a layer of low-level clouds downstream. The surface solar heating through this hole, in combination with the tongue of low-level high θw air associated with the front, caused the shower to initiate with sufficient lifting to enable it later to break through the lid.
The Institutionalization of Racial Profiling Policy
Authors: Miller Kirk
Published: February 2009

The issue of racial profiling has come to represent one of the key contemporary challenges facing law enforcement agencies in the United States. One way that agencies have responded to this issue is to adopt anti-profiling policies to address concerns about racial disparities in traffic stops and their outcomes. Policy adoption is assumed to encourage more racially equitable policing as well as enhance community relations. While both of these outcomes appear beneficial to law enforcement agencies, there is also good reason to expect that agencies may differ in the extent to which they are likely to implement such policy. This study explores what factors explain the adoption of protocols addressing the racial profiling phenomenon. Using data on large law enforcement agencies from the 2003 LEMAS survey, the findings reveal that both agency organizational characteristics and environmental features of the jurisdiction are associated with the agency’s profiling policy regime.
Discrete-Time Multi-Resolution Modeling of Switching Power Converters Using Wavelets
Authors: Ponci Ferdinanda , Santi Enrico , Monti Antonello
Published: February 2009

Modeling of power electronics circuits presents significant challenges due to the non-linear time-varying behaviour of this kind of system. It is common practice to operate with families of models of different complexity depending on the analysis goal. In this paper we propose a wavelet-based approach as a unifying framework able to provide multi-resolution capabilities and consequently significant flexibility to the modeling process. The comparison with more classical approaches to power converter modeling demonstrates how this approach can be considered an extension of formalizations such as state-space averaging. Simulation results for both DC-DC and DC-AC power converters, including soft-switching configurations, are presented as sample applications. The discrete-time formulation makes this approach particularly suitable for design and analysis of converters operated with digital controllers.
A Genetic Algorithm-based Solution Search to Fuzzy Logical Inference for Breakdown Causes in Fabric Inspection
Authors: Lin Jeng-Jong
Published: February 2009

This study presents an intelligent diagnosis system consisting of a screening mechanism, which can effectively narrow down the search range for possible breakdown causes, and a search mechanism (based on genetic algorithm), which can help find the solution (i.e., upper boundaries and lower ones) to the inverse fuzzy equation. Through their integration, an intelligent diagnosis system is developed. With the assistance of this system, an operator can find more easily and effectively possible occurred breakdown causes by the observed symptoms during fabric weaving process.
Impact Tests on Lincoln Wool Fibers Using a Mini Split Hopkinson Tensile Bar
Authors: Dong Ruan  , Ming Yan Leung  , Guoxing Lu  , Tongxi Yu  , Jinan Cao  , Blicblau Aaron Simon
Published: February 2009

A new testing method using a mini split Hopkinson tensile bar was employed in the impact tests of Lincoln wool fibers. Stress-strain curves of Lincoln wool fibers subjected to impact loadings at strain rates in the order of 102s—1were obtained, which fill the gap in the impact data for Lincoln wool fibers. For comparison, quasi-static tests were also carried out with a single Lincoln wool fiber using a Micro-Tester. Stress level was observed to increase with increasing strain rates.