bluuebunny/crossref_metadata_2025 huggingface dataset:
Rate effects from pile shaft resistance measurements
Authors: Brown Michael John , Hyde Adrian Frank Luciano
Published: April 2008

To be able to properly analyse rapid load pile tests in clay soils (e.g., Statnamic) an understanding of the material’s behaviour at elevated shearing rates is required, as clays demonstrate nonlinear shearing resistance as the rate of shearing increases. To determine the relationship between pile resistance under static and elevated rates of loading, rate effect parameters for viscous damping have historically been derived from pile head measurements on full scale pile tests. These parameters are then attributed to a soil type with little recognition of what aspects of a soil may give further variation to them. To study this variation a test pile was installed in glacial till and instrumented with strain gauged sister bars at various levels down the pile shaft. Direct measurements of pile shaft resistance in both rapid load and static pile tests show that derivation of average parameters from pile head readings masks the variation in rate effect along a pile shaft. The variation of rate effects along the pile shaft is apparently linked to in situ moisture content.
Comparing antibiotic resistance in commensal and pathogenic bacteria isolated from wild-caught South Carolina shrimps vs. farm-raised imported shrimps
Authors: Boinapally Kavitha , Jiang Xiuping
Published: April 2008

The objective of this study was to assess and differentiate wild-caught South Carolina (SC) shrimps from imported shrimps on the basis of microbiological analysis. Seven wild-caught SC shrimp and 13 farm-raised imported shrimp samples were analyzed. Total plate counts from wild-caught shrimp samples ranged from 4.3 to 7.0 log10 CFU/g, whereas counts from imported shrimp samples ranged from 3.2 to 5.7 log10 CFU/g. There was no difference (P > 0.05) between total bacterial counts of wild-caught SC shrimp and farm-raised imported shrimp. However, the percentages of bacteria with reduced susceptibility towards ceftriaxone and tetracycline were higher (P < 0.05) for farm-raised shrimp than for wild-caught samples. Salmonella spp. detected only in one farm-raised sample was resistant to ampicillin, ceftriaxone, gentamicin, streptomycin, and trimethoprim. Vibrio vulnificus was detected in both wild-caught and farm-raised shrimp samples; however, only the isolate from farm-raised shrimp was resistant to nalidixic acid and trimethoprim. Escherichia coli detected in one wild-caught sample was resistant to ampicillin. Both Listeria spp. and Salmonella spp. were absent with wild-caught SC samples. Therefore, the presence of more ceftriaxone- and tetracycline-resistant bacteria and the observed antimicrobial resistance phenotypes of isolates from the imported shrimp may reflect the possible use of antibiotics in raising shrimp in those countries.
1-Aminocyclopropane-1-carboxylate deaminase from Pseudomonas putida UW4 facilitates the growth of canola in the presence of salt
Authors: Cheng Zhenyu , Park Eunmi , Glick Bernard R.
Published: April 2008

The growth of canola plants treated with either wild-type Pseudomonas putida UW4 or a 1-aminocyclopropane-1-carboxylate (ACC) deaminase minus mutant of this strain was monitored in the presence of inhibitory levels of salt, i.e., 1.0 mol/L at 10 °C and 150 mmol/L at 20 °C. This strain is psychrotolerant with a maximal growth rate of approximately 30 °C and the ability to proliferate at 4 °C. Although plant growth was inhibited dramatically by the addition of 1.0 mol/L salt at 10 °C and only slightly by 150 mmol/L salt at 20 °C under both sets of conditions, the addition of the wild type but not the mutant strain of P. putida UW4 significantly improved plant growth. This result confirms the previous suggestion that bacterial strains that contain ACC deaminase confer salt tolerance to plants by lowering salt-induced ethylene synthesis.
SUCCINCT MINIMAL GENERATORS: THEORETICAL FOUNDATIONS AND APPLICATIONS
Authors: HAMROUNI TAREK , BEN YAHIA SADOK , MEPHU NGUIFO ENGELBERT
Published: April 2008

In data mining applications, highly sized contexts are handled what usually results in a considerably large set of frequent itemsets, even for high values of the minimum support threshold. An interesting solution consists then in applying an appropriate closure operator that structures frequent itemsets into equivalence classes, such that two itemsets belong to the same class if they appear in the same sets of objects. Among equivalent itemsets, minimal elements (w.r.t. the number of items) are called minimal generators (MGs), while their associated closure is called closed itemset (CI), and is the largest one within the corresponding equivalence class. Thus, the pairs - composed by MGs and their associated CIs - make easier localizing each itemset since it is necessarily encompassed by an MG and an CI. In addition, they offer informative implication/association rules, with minimal premises and maximal conclusions, which losslessly represent the entire rule set. These important concepts - MG and CI - were hence at the origin of various works. Nevertheless, the inherent absence of a unique MG associated to a given CI leads to an intra-class combinatorial redundancy that leads an exhaustive storage and impractical use. This motivated an in-depth study towards a lossless reduction of this redundancy. This study was started by Dong et al. who introduced the succinct system of minimal generators (SSMG) as an attempt to eliminate the redundancy within this set. In this paper, we give a thorough study of the SSMG as formerly defined by Dong et al. This system will be shown to suffer from some flaws. As a remedy, we introduce a new lossless reduction of the MG set allowing to overcome its limitations. The new SSMG will then be incorporated into the framework of generic bases of association rules. This makes it possible to only maintain succinct and informative rules. After that, we give a thorough formal study of the related inference mechanisms allowing to derive all redundant association rules, starting from the maintained ones. Finally, an experimental evaluation shows the utility of our approach towards eliminating important rate of redundant information.
ADJUSTING ANNOTATED TAXONOMIES
Authors: KAISER TIM B. , SCHMIDT STEFAN E. , JOSLYN CLIFF A.
Published: April 2008

We show how the concept of an annotated ordered set can be used to model large taxonomically structured ontologies such as the Gene Ontology. By constructing a formal context consistent with a given annotated ordered set, their concept lattice representations are derived. We develop the fundamental mathematical relations present in this formulation, in particular deriving a conceptual pre-ordering of the taxonomy, and constructing a correspondence between the annotations of an ordered set and the closure systems of its filter lattice. We study an example from the Gene Ontology to demonstrate how the introduced technique can be utilized for taxonomy review.
VARIATIONS OF BASE-STATION PLACEMENT PROBLEM ON THE BOUNDARY OF A CONVEX REGION
Authors: DAS GAUTAM K. , ROY SASANKA , DAS SANDIP , NANDY SUBHAS C.
Published: April 2008

This paper deals with an important problem of mobile communication. The objective is to place k base stations of equal range on the boundary of a convex polygonal region P such that each point inside P is covered by at least one base station. We name this problem as region-cover(k) problem. A simplified form of this problem is the vertex-cover(k) problem, where the objective is to communicate with only the vertices of P instead of covering the entire polygon. We first present efficient algorithms for vertex-cover(2) and region-cover(2) problems, where the base stations are to be installed on a pair of specified edges. The time complexity of these algorithms are O(n log n) and O(n2) respectively, where n is the number of vertices in the polygon P. Next, we consider the case where k ≥ 3. We first concentrate on a restricted version of the vertex-cover(k) and region-cover(k) problems, where all the k base stations are to be installed on the same edge of P. Our proposed algorithm for the restricted vertex-cover(k) problem produces optimum result in O(min(n2,nk log n)) time, whereas the algorithm for the restricted region-cover(k) problem produces an (1 + ∊)-factor approximation result in [Formula: see text] time. Finally, we propose efficient heuristic algorithm for the unrestricted version of the region-cover(k) problem for k ≥ 3. Experimental results demonstrate that our proposed algorithm runs fast and produces near optimum solutions.
RANK AND CONGRUENCES FOR OVERPARTITION PAIRS
Authors: BRINGMANN KATHRIN , LOVEJOY JEREMY
Published: April 2008

The rank of an overpartition pair is a generalization of Dyson's rank of a partition. The purpose of this paper is to investigate the role that this statistic plays in the congruence properties of [Formula: see text], the number of overpartition pairs of n. Some generating functions and identities involving this rank are also presented.
PROPERTIES OF VARIETIES DETERMINED BY THE DEGREES OF PROPER HYPERSUBSTITUTIONS
Authors: Denecke Klaus , Srithus Rattana
Published: April 2008

The degree of proper hypersubstitutions is a numerical invariant of a variety. The main problem related to the degree of proper hypersubstitutions is to characterize all varieties of a given type τ which have, for a given positive integer n, this n as degree of proper hypersubstitutions. In this paper we answer to this question for solid varieties and certain integers as degrees and then for not necessarily solid varieties of type τ = (n) satisfying some additional conditions.
THERE DOES NOT EXIST AN ODD SINGULAR NUMBER OF THE FORM plqr
Authors: Hong Shaofang , Wang Shaofang
Published: April 2008

Motivated by his solution to the Bourque-Ligh conjecture on the nonsingularity of the least common multiple matrix defined on the gcd-closed set, Hong introduced the concept of primitive singular number. Meanwhile Hong proved that there does not exist a singular number with no more than two distinct prime factors. Hong and Shum as well Sun showed in 2006 that there are even primitive singular numbers of the form plqr, where p, q, r are distinct primes and l is a positive integer. In this paper, we show that there does not exist an odd singular number of the form plqr. This improves a result obtained by Hong and Shum as well Sun and also confirms partially a conjecture of Hong.
Specific overexpression of IL-7 in the intestinal mucosa: the role in intestinal intraepithelial lymphocyte development
Authors: Yang Hua , Madison Blair , Gumucio Deborah L. , Teitelbaum Daniel H.
Published: April 2008

IL-7 plays a crucial role in controlling T cell development and homeostasis. Since IL-7 may be derived from extraintestinal sources, and exogenous IL-7 broadly affects lymphoid populations, the actions of epithelial cell (EC)-derived IL-7 are not fully understood. The effect of intestinal specific expression of IL-7 on intestinal mucosal lymphocytes was investigated by using an IL-7 transgenic mouse model. We generated an intestinal EC-specific overexpressing IL-7 transgenic mouse model (IL-7vill) and compared their phenotype and function to wild-type C57BL/6J mice. EC-derived IL-7 overexpression was found to be exclusively in the small and large intestine. Numbers and subtypes of mucosal lymphocytes, including intraepithelial lymphocytes (IEL) and lamina propria lymphocytes (LPL), significantly changed in IL-7villmice. From a functional standpoint, IEL proliferation also significantly increased in IL-7villmice. IEL cytokine expression significantly changed in both T cell receptor (TCR)-αβ+and TCR-γδ+IEL subpopulations, including a significant increase in IFN-γ and TNF-α as well as an increase in keratinocyte growth factor expression. EC expression of CD103 (integrin αEβ7), the ligand of E-cadherin, markedly upregulated and may account for a mechanism of the massive expansion of IEL in transgenic mice. Systemic lymphoid populations did not change in transgenic mice. IL-7 overexpression by intestinal EC significantly affected IEL phenotype and function. These results offer insight into the role of IL-7 in IEL development and suggest a critical role of EC-derived expression of IL-7 in the phenotype and function of IEL.
p38 MAPK-dependent eNOS upregulation is critical for 17β-estradiol-mediated cardioprotection following trauma-hemorrhage
Authors: Kan Wen-Hong , Hsu Jun-Te , Ba Zheng-Feng , Schwacha Martin G. , Chen Jianguo , Choudhry Mashkoor A. , Bland Kirby I. , Chaudry Irshad H.
Published: April 2008

Studies have shown that p38 MAPK and nitric oxide (NO), generated by endothelial NO synthase (eNOS), play key roles under physiological and pathophysiological conditions. Although administration of 17β-estradiol (E2) protects cardiovascular injury from trauma-hemorrhage, the mechanism by which E2 produces those effects remains unknown. Our objective was to determine whether the E2-mediated activation of myocardial p38 MAPK and subsequent eNOS expression/phosphorylation would protect the heart following trauma-hemorrhage. To study this, male Sprague-Dawley rats underwent soft-tissue trauma (midline laparatomy) and hemorrhagic shock (mean blood pressure 35–40 mmHg for 90 min), followed by fluid resuscitation. Animals were pretreated with specific p38 MAPK inhibitor SB-203580 (SB; 2 mg/kg), and nonselective NO synthase inhibitor NG-nitro-l-arginine methyl ester (l-NAME; 30 mg/kg) 30 min before vehicle (cyclodextrin) or E2 (100 μg/kg) treatment, followed by resuscitation, and were killed 2 h thereafter. Cardiovascular performance and other parameters were measured. E2 administration following trauma-hemorrhage increased cardiac p38 MAPK activity, eNOS expression and phosphorylation at Ser1177, and nitrate/nitrite levels in plasma and heart tissues; these were associated with normalized cardiac performance, which was reversed by SB administration. In addition, E2 also prevented trauma-hemorrhage-induced increase in cytokines (IL-6 and TNF-α), chemokines (macrophage inflammatory protein-2 and cytokine-induced neutrophil chemoattractant-1), and ICAM-1, which was reversed by l-NAME administration. Administration of E2 following trauma-hemorrhage attenuated cardiac tissue injury markers, myeloperoxidase activity, and nitrotyrosine level, which were reversed by treatment with SB and l-NAME. The salutary effects of E2 on cardiac functions and tissue protection following trauma-hemorrhage are mediated, in part, through activation of p38 MAPK and subsequent eNOS expression and phosphorylation.
Connexin 40 and ATP-dependent intercellular calcium wave in renal glomerular endothelial cells
Authors: Toma Ildikó , Bansal Eric , Meer Elliott J. , Kang Jung Julie , Vargas Sarah L. , Peti-Peterdi János
Published: April 2008

Endothelial intracellular calcium ([Ca2+]i) plays an important role in the function of the juxtaglomerular vasculature. The present studies aimed to identify the existence and molecular elements of an endothelial calcium wave in cultured glomerular endothelial cells (GENC). GENCs on glass coverslips were loaded with Fluo-4/Fura red, and ratiometric [Ca2+]iimaging was performed using fluorescence confocal microscopy. Mechanical stimulation of a single GENC caused a nine-fold increase in [Ca2+]i, which propagated from cell to cell throughout the monolayer (7.9 ± 0.3 μm/s) in a regenerative manner (without decrement of amplitude, kinetics, and speed) over distances >400 μm. Inhibition of voltage-dependent calcium channels with nifedipine had no effect on the above parameters, but the removal of extracellular calcium reduced Δ[Ca2+]iby 50%. Importantly, the gap junction uncoupler α-glycyrrhetinic acid or knockdown of connexin 40 (Cx40) by transfecting GENCs with Cx40 short interfering RNA (siRNA) almost completely eliminated Δ[Ca2+]iand the calcium wave. Breakdown of extracellular ATP using a scavenger cocktail (apyrase and hexokinase) or nonselective inhibition of purinergic P2 receptors with suramin, had similar blocking effects. Scraping cells off along a line eliminated physical contact between cells but did not effect calcium wave propagation. Using an ATP biosensor technique, we detected a significant elevation in extracellular ATP (Δ = 76 ± 2 μM) during calcium wave propagation, which was abolished by Cx40 siRNA treatment (Δ = 6 ± 1 μM). These studies suggest that connexin 40 hemichannels and extracellular ATP are key molecular elements of the glomerular endothelial calcium wave, which may serve important juxtaglomerular functions.
AT1 blockade during lactation as a model of chronic nephropathy: mechanisms of renal injury
Authors: Machado Flavia Gomes , Poppi Elizabete Pereira Barros , Fanelli Camilla , Malheiros Denise Maria Avancini Costa , Zatz Roberto , Fujihara Clarice Kazue
Published: April 2008

Suppression of the renin-angiotensin system during lactation causes irreversible renal structural changes. In this study we investigated 1) the time course and the mechanisms underlying the chronic kidney disease caused by administration of the AT1 receptor blocker losartan during lactation, and 2) whether this untoward effect can be used to engender a new model of chronic kidney disease. Male Munich-Wistar pups were divided into two groups: C, whose mothers were untreated, and LLact, whose mothers received oral losartan (250 mg·kg−1·day−1) during the first 20 days after delivery. At 3 mo of life, both nephron number and the glomerular filtration rate were reduced in LLact rats, whereas glomerular pressure was elevated. Unselective proteinuria and decreased expression of the zonula occludens-1 protein were also observed, along with modest glomerulosclerosis, significant interstitial expansion and inflammation, and wide glomerular volume variation, with a stable subpopulation of exceedingly small glomeruli. In addition, the urine osmolality was persistently lower in LLact rats. At 10 mo of age, LLact rats exhibited systemic hypertension, heavy albuminuria, substantial glomerulosclerosis, severe renal interstitial expansion and inflammation, and creatinine retention. Conclusions are that 1) oral losartan during lactation can be used as a simple and easily reproducible model of chronic kidney disease in adult life, associated with low mortality and no arterial hypertension until advanced stages; and 2) the mechanisms involved in the progression of renal injury in this model include glomerular hypertension, glomerular hypertrophy, podocyte injury, and interstitial inflammation.
Application of cross-sectional time series modeling for the prediction of energy expenditure from heart rate and accelerometry
Authors: Zakeri Issa , Adolph Anne L. , Puyau Maurice R. , Vohra Firoz A. , Butte Nancy F.
Published: April 2008

Accurate estimation of energy expenditure (EE) in children and adolescents is required for a better understanding of physiological, behavioral, and environmental factors affecting energy balance. Cross-sectional time series (CSTS) models, which account for correlation structure of repeated observations on the same individual, may be advantageous for prediction of EE. CSTS models for prediction of minute-by-minute EE and, hence, total EE (TEE) from heart rate (HR), physical activity (PA) measured by accelerometry, and observable subject variables were developed in 109 children and adolescents by use of Actiheart and 24-h room respiration calorimetry. CSTS models based on HR, PA, time-invariant covariates, and interactions were developed. These dynamic models involve lagged and lead values of HR and lagged values of PA for better description of the series of minute-by-minute EE. CSTS models with random intercepts and random slopes were investigated. For comparison, likelihood ratio tests were used. Log likelihood increased substantially when random slopes for HR and PA were added. The population-specific model uses HR and 1- and 2-min lagged and lead values of HR, HR2, and PA and 1- and 2-min lagged values of PA, PA2, age, age2, sex, weight, height, minimum HR, sitting HR, HR × height, HR × weight, HR × age, PA × weight, and PA × sex interactions ( P < 0.001). Prediction error for TEE was 0.9 ± 10.3% (mean ± SD). Errors were not correlated with age, weight, height, or body mass index. CSTS modeling provides a useful predictive model for EE and, hence, TEE in children and adolescents on the basis of HR and PA and other observable explanatory subject characteristics of age, sex, weight, and height.
Nuclear Factor-kappa B as a Resistance Factor to Platinum-Based Antineoplasic Drugs
Authors: Lagunas Vilma Maldonado , Meléndez-Zajgla Jorge
Published: April 2008

Platinum drugs continue to be major chemotherapy drugs for cancer treatment. Nevertheless, acquired or intrinsic resistance to these compounds is common in human tumors. One important mechanism for this resistance is the avoidance of cells entering the apoptotic pathway. Nuclear factor-kappa B (NF-kappa B, NF-κB) is a pleiotropic transcription factor key in determining the death threshold of human cells. This factor is important in the final response of cells to platinum drugs, as exemplified by in vitro and in vivo models showing that inhibition of NF-κB sensitizes cancer cells to the effects of these drugs. New approaches focusing on the inhibition of NF-κB could help to minimize or even eliminate intrinsic or acquired resistance to platinum drugs.
Prolactin Does Not Require Insulin-Like Growth Factor Intermediates but Synergizes with Insulin-Like Growth Factor I in Human Breast Cancer Cells
Authors: Carver Kristopher C. , Schuler Linda A.
Published: April 2008

Insulin-like growth factor (IGF)-II is a required intermediate for prolactin-induced up-regulation of cyclin D1 and proliferation in normal murine mammary epithelial cells in vivo and in vitro. However, we have recently shown that prolactin can rapidly induce cyclin D1 protein expression and subsequent proliferation in the MCF-7 human breast cancer cell line, suggesting that prolactin actions can be independent of IGFs in breast disease. Here, we investigate the relationship between these factors and show that prolactin up-regulated transcript levels of both IGF-I and IGF-II, but only after increases in cyclin D1 protein were observed. Moreover, prolactin increased cyclin D1 in the presence of the IGF-I receptor neutralizing antibody αIR3. However, on cotreatment, IGF-I and prolactin elicited cooperative phosphorylation of extracellular signal–regulated kinases 1 and 2 and protein kinase B/AKT, but not signal transducer and activator of transcription 5. This interaction extended to increased activation of activating protein-1 enhancer elements, phosphorylation of glycogen synthase kinase 3β, induction of cyclin D1, and ultimately, increased cell number. It also increased invasive behavior, which correlated with elevated matrix metalloproteinase-2 transcript levels. Interestingly, prolactin augmented phosphorylation at Tyr1135 and Tyr1136 of IGF-I receptor on cotreatment with IGF-I, although prolactin alone had no effect. Together, these data indicate that strong cooperative cross talk between prolactin and IGF-I augments biological processes associated with neoplastic progression, with implications for therapeutic strategies. (Mol Cancer Res 2008;6(4):634–43)
Tension-Free Vaginal Tape and Autologous Rectus Fascia Pubovaginal Sling for the Treatment of Urinary Stress Incontinence: A Medium-Term Follow-Up
Authors: Sharifiaghdas Farzaneh , Mortazavi Nassrin
Published: April 2008

Objectives: To compare two different procedures, tension-free vaginal tape (TVT) and autologous rectus fascia sling, according to their medium-term subjective and objective outcomes and satisfaction rates in the treatment of urinary stress incontinence in women. Subjects and Methods: One hundred women with type II urinary stress incontinence were randomized to be treated with either TVT or autologous rectus fascia sling. They were evaluated by means of a cough-induced stress test, 1-hour pad test, Incontinence Impact Questionnaire (IIQ), and urodynamic study. They were reevaluated postoperatively every 6 months, and the collected data of more than 1 year’s follow-up were compared with preoperative assessments. Results: All patients completed the full 6-month postoperative assessment. However, of the 100 patients, only 61 (25 in the TVT and 36 in the sling group) were followed for more than 1 year. Mean follow-up time was 38.5 and 40 months in the TVT and sling group, respectively. Objective cure was achieved in 22 (88%) of the TVT group and in 30 (83%) of the sling group (p = 0.78) using a cough-induced stress test, and in 76 and 75% of the women in the TVT versus sling group (p = 0.83), respectively, using a 1-hour pad test. Postoperative mean IIQ scores were 44.3 (range 35.5–61.5) and 48.5 (range 38.5–69.7) in the TVT versus sling group (p = 0.46). Five (20%) and 11 (30%) of the TVT and sling group, respectively, reported some changes in the voiding pattern or posture at more than 1 year’s follow-up. Conclusion: There is no significant difference between the TVT and autologous rectus fascia sling procedures in the treatment of urinary stress incontinence at medium-term follow-up. There were changes in the voiding pattern for patients in both groups at more than 1 year postoperatively, which were not evident at early follow-up.
An Unusual Association between Familial Mediterranean Fever and IgM Nephropathy
Authors: Peru Harun , Elmaci Ahmet Midhat , Akin Fatih , Akcoren Zuhal , Orhan Diclehan
Published: April 2008

Objective: To report a case with the diagnosis of IgM nephropathy and familial Mediterranean fever (FMF). Clinical Presentation and Intervention: A 9-year-old boy was admitted to our hospital with recurrent abdominal pain since the age of 4 years. Laboratory investigations revealed a sedimentation rate of 88 mm/h, C-reactive protein: 83.2 mg/l (0–10 mg/l), white blood cell count: 12,700/mm3, fibrinogen: 622 mg/dl (200–400 mg/dl) and serum amyloid A: 186 mg/l (0–5.8 mg/l). Urinalysis revealed +2 proteinuria. A 24-hour urinary protein excretion was 12 mg/m2/h. M694V homozygous mutation was identified in exon 10. Percutaneous renal biopsy showed mesangial cell proliferation and increased mesangial matrix in the glomeruli, without amyloid accumulation. Immunofluorescence study showed IgM (+1) and C1q (+1) deposits. Treatment with 1 mg/day colchicine was started. Six weeks later, proteinuria had disappeared and the patient was asymptomatic. Conclusion: This case illustrates the unusual association of FMF with non-amyloid glomerulopathy. Glomerular diseases such as IgM nephropathy may be seen as a manifestation of FMF.
Correlation of Coronary Artery Atherosclerosis with Atherosclerosis of the Intracranial Cerebral Artery and the Extracranial Carotid Artery
Authors: Seo Woo-Keun , Yong Hwan S. , Koh Seong-Beom , Suh Sang-il , Kim Ji H. , Yu Sung-Wook , Lee Ji-Yeon
Published: April 2008

Background: Investigating atherosclerosis of the coronary artery in ischemic stroke patients is clinically important because comorbidity is relatively common in such patients. We studied the relationship of atherosclerosis of the coronary artery to atherosclerosis of the intracranial cerebral artery and extracranial carotid artery. Further investigation was performed for determining the factors independently associated with coronary artery atherosclerosis in ischemic stroke patients. Methods: We consecutively recruited ischemic stroke patients who had no history of coronary artery disease, and they underwent vascular examination. Patient-based vascular assessment was performed with magnetic resonance angiography of the cerebral arteries and computed tomography coronary angiography. The factors independently associated with coronary artery stenosis (≧50%) were obtained from the conventional vascular risk factors and cerebral arterial stenosis using the logistic regression model. Results: Coronary artery stenosis was observed in 25.4% of the patients and this was associated with age (OR: 1.16, 95% CI: 1.03–1.30) and the presence of stenosis of the extracranial carotid artery (OR: 11.37, 95% CI: 1.88–68.75) after logistic regression analysis. Intracranial arterial stenosis was not independently related to coronary stenosis. Conclusion: Careful concern about coronary artery disease is needed when treating ischemic stroke patients who have atherosclerosis of the extracranial carotid artery.
Lack of an Association between Alzheimer’s Disease and the Cystatin C (CST3) Gene G73A Polymorphism in Mainland Chinese
Authors: Wang Binbin , Xie Yan-chen , Yang Ze , Peng Dantao , Wang Jing , Zhou Sirui , Li Shu , Ma Xu
Published: April 2008

Alzheimer’s disease (AD) is a complex multifactorial disorder involving a number of genetic and environmental factors. Cystatin C (CST3), which belongs to the type II cystatin gene family, is a potent inhibitor of lysosomal proteinases. Immunohistochemical studies have demonstrated the colocalization of the b-amyloid (A-beta) and cystatin C peptides within arteriolar walls in the AD brain. The G73A polymorphism of the CST3 genemay be associated with AD development. To investigate a possible association between the CST3 G73A polymorphism and late-onset AD (LOAD) in Mainland Chinese, we examined 281 LOAD patients and 376 healthy controls. All subjects were genotyped for CST3 and apolipoprotein E (APOE). There were no significant differences in the CST3 genotype or allele frequencies between the cases and the controls. Likewise, with the stratification of the APOE Ε4 status, no statistical difference was observed between the cases and the controls. Our findings suggest that this polymorphism may not represent an additional genetic risk factor for LOAD in Mainland Chinese.
A Comparison of Methods to Detect Recombination Hotspots
Authors: Tapper William , Gibson Jane , Morton Newton E. , Collins Andrew
Published: April 2008

Objective: A number of linkage disequilibrium (LD)-based methods have been developed to describe recombination and infer hotspots. We determine the correspondence between LDMAP and LDhat, and between LDMAP and LDhot by comparison with linkage maps and hotspots that have been verified by sperm typing. Methods: Regression and variance analyses were used to compare LDMAP and LDhat with linkage maps. The location and intensity of hotspots inferred by LDMAP and LDhot were compared with fifteen verified hotspots. Results: Despite different methodologies and assumptions, LDMAP, LDhat, and linkage maps are highly concordant. Closer inspection shows that LDMAP corresponds more closely with linkage maps across the genome and on sixteen chromosomes compared with LDhat. LDhot identified fourteen and ten of the verified hotspots using high and low density maps. In comparison, LDMAP identified all fifteen hotspots at high and low density. However, some significant discrepancies between sperm and LD-based recombination rates remain. Conclusions: Combining information from linkage and LDMAP to construct sex-specific high resolution linkage maps suggests that some of these discrepancies may be due to female recombination while others may relate to the age of hotspots. LDMAP based estimates between ∼68,000 and ∼112,000 hotspots in the genome with mean widths less than 4 kb.
Cognition, Continence and Transfer Status at the Time of Discharge from an Acute Hospital Setting and Their Associations with an Unfavourable Discharge Outcome after Stroke
Authors: Myint Phyo K. , Vowler Sarah L. , Redmayne Oliver , Fulcher Robert A.
Published: April 2008

Background: Current demographic trends pose a major societal challenge due to the rising number of older people with chronic conditions such as stroke. The relative impact of various disabilities at the time of discharge from an acute unit on discharge outcome is poorly understood. Objective: To examine the association between cognition, continence and transfer status at the time of discharge from the acute stroke unit and discharge destination. Methods: A retrospective stroke register database study was conducted in an acute stroke unit in a UK hospital with a catchment population of 568,000. Consecutive acute stroke admissions between 1997 and 2003 who were discharged alive were identified and the likelihood of adverse discharge outcomes defined as institutionalization or a requirement for longer-term rehabilitation was estimated. Results: A total of 2,521 discharges were analyzed (median length of hospital stay 8 days). The presence of confusion, urinary incontinence or the need for help with transfers at the time of discharge predicted a higher likelihood of an adverse outcome even after controlling for age, stroke subtype, premorbid Rankin score and length of hospital stay. The need for help with transfers appeared to be the most consistent and significant factor associated with an adverse outcome regardless of age, sex or stroke subtype across the sample distribution. Conclusion: The ability to transfer has a pivotal role in the clinical decision making of discharge destination after stroke. Understanding of the factors which may increase the potential for improving this ability after acute stroke could have an impact on clinical outcome.
The direct thrombin inhibitor hirudin
Authors: Warkentin Theodore , Greinacher Andreas
Published: April 2008

This review discusses the pharmacology and clinical applications of hirudin, a bivalent direct thrombin inhibitor (DTI). Besides the current major indication for hirudin – anticoagulation of patients with heparin-induced thrombocytopenia (HIT) – the experience with hirudin in other indications, especially acute coronary syndromes, are briefly presented. Hirudins have been formally studied prior to their regulatory approval; however, important information on their side effects and relevant preventative measures only became available later. Therefore, current recommendations and dosing schedules for hirudin differ considerably from the information given in the package inserts. Drawbacks of hirudin and important precautions for avoiding potential adverse effects are discussed in detail in the third part of this review.
Venous and arterial thromboembolism in severe sepsis
Authors: LeClerc Jacques , Bailey Joan , Monberg Matthew , Sarwat Samiha , Levine Robert
Published: April 2008

The burden of thromboembolism (TE) in severe sepsis is largely unknown. We assessed the prevalence of venous and arterial TE in patients with severe sepsis over a four-week period. We performed a retrospective analysis of a pooled database of three randomized, placebo-controlled trials of two novel pharmacological agents for the treatment of severe sepsis, drotrecogin alfa (activated) (DrotAA)and secretory phospholipase A2 inhibitor (sPLA2I). The study was conducted at intensive care units of the participating institutions. A total of 2,649 patients with known or suspected infection and sepsis-associated acute organ dysfunction were enrolled in the three trials and were assigned to treatment groups (DrotAA=850; sPLA2I =578; placebo=1221). The database was queried for venous and arterial TE, using investigator reports of serious adverse events. Eighty-four of 2,649 patients (3.2%; 95% confidence interval, 2.5% to 3.9%) developed at least one thromboembolic event over 28 days. Nearly threequarters of episodes were atheroembolic (n=62); 25% involved the deep venous system (n=25). Ischemic stroke (n=30) and venous thromboembolism (n=25) each occurred in about 1% of patients. Ischemic stroke and acute coronary syndrome had a higher peak incidence during the first five days compared to venous TE onset, which was more constant over the 28-day period. Subgroup analysis by pooled treatment groups yielded TE rates of 2.0% (DrotAA), 3.5% (placebo), and 4.0% (sPLA2I), respectively. Clinically manifest TE occurred in about 3% of severe sepsis patients treated in the intensive care unit over a 28-day period. Arterial TE may be more common than previously recognized. More accurate estimates of TE prevalence and relationship to sepsis await future studies.
High-Sensitivity C-Reactive Protein and Coronary Heart Disease in a General Population of Japanese
Authors: Arima Hisatomi , Kubo Michiaki , Yonemoto Koji , Doi Yasufumi , Ninomiya Toshiharu , Tanizaki Yumihiro , Hata Jun , Matsumura Kiyoshi , Iida Mitsuo , Kiyohara Yutaka
Published: April 2008

Objective—

The purpose of this study was to investigate the effects of high-sensitivity C-reactive protein (hs-CRP) on the risks of coronary heart disease (CHD) in a general population of Japanese.

Methods and Results—

The Hisayama study is a population-based prospective cohort study. A total of 2589 participants aged 40 years or older were followed up for 14 years. Outcomes are incident CHD (myocardial infarction, coronary revascularization, and sudden cardiac death). The median hs-CRP level was 0.43 mg/L at baseline. During the follow-up period, 129 coronary events were observed. Age- and sex-adjusted annual incidence rates of CHD rose progressively with higher hs-CRP levels: 1.6, 3.3, 4.5, and 7.4 per 1000 person-years for quartile groups defined by hs-CRP levels of <0.21, 0.21 to 0.43, 0.44 to 1.02, and >1.02 mg/L, respectively (
P
<0.0001 for trend). The risk of CHD in the highest quartile group was 2.98-fold (95% CI, 1.53 to 5.82) higher than that in the lowest group even after controlling for other cardiovascular risk factors.

Conclusions—

hs-CRP levels were clearly associated with future CHD events in a general population of Japanese. In Japanese populations, the hs-CRP cut-off point for high-risk of future development of CHD is likely to be >1.0 mg/L, which is much lower than that for Western populations.
Training of Reaching in Stroke Survivors With Severe and Chronic Upper Limb Paresis Using a Novel Nonrobotic Device
Authors: Barker Ruth N. , Brauer Sandra G. , Carson Richard G.
Published: April 2008

Background and Purpose—

Severe upper limb paresis is a major contributor to disability after stroke. This study investigated the efficacy of a new nonrobotic training device, the Sensorimotor Active Rehabilitation Training (SMART) Arm, that was used with or without electromyography-triggered electrical stimulation of triceps brachii to augment elbow extension, permitting stroke survivors with severe paresis to practice a constrained reaching task.

Methods—

A single-blind, randomized clinical trial was conducted with 42 stroke survivors with severe and chronic paresis. Thirty-three participants completed the study, of whom 10 received training using the SMART Arm with electromyography-triggered electrical stimulation, 13 received training using the SMART Arm alone, and 10 received no intervention (control). Training consisted of 12 1-hour sessions over 4 weeks. The primary outcome measure was “upper arm function,” item 6 of the Motor Assessment Scale. Secondary outcome measures included impairment measures; triceps muscle strength, reaching force, modified Ashworth scale; and activity measures: reaching distance and Motor Assessment Scale. Assessments were administered before (0 weeks) and after training (4 weeks) and at 2 months follow-up (12 weeks).

Results—

Both SMART Arm groups demonstrated significant improvements in all impairment and activity measures after training and at follow-up. There was no significant difference between these 2 groups. There was no change in the control group.

Conclusions—

Our findings indicate that training of reaching using the SMART Arm can reduce impairment and improve activity in stroke survivors with severe and chronic upper limb paresis, highlighting the benefits of intensive task-oriented practice, even in the context of severe paresis.
Characterization of Cortical Microvascularization in Adult Moyamoya Disease
Authors: Czabanka Marcus , Peña-Tapia Pablo , Schubert Gerrit A. , Woitzik Johannes , Vajkoczy Peter , Schmiedek Peter
Published: April 2008

Background and Purpose—

Increased cortical microvascularization has been proposed to be a Moyamoya disease (MMD)–specific characteristic. It was the aim of our study to characterize the anatomic pattern and microhemodynamics of cortical microvascularization in MMD.

Methods—

Intraoperative indocyanine green videoangiography was performed in 16 adult MMD patients, 15 patients with atherosclerotic cerebrovascular disease (ACVD), and 10 control patients. Cortical microvascularization and microvascular hemodynamics were categorized and analyzed according to anatomic and functional indocyanine green angiographic aspects. Anatomic analysis included microvascular density, microvascular diameter, and microvascular surface per analyzed area. Microhemodynamic analysis included microvascular transit time, arterial microvascular transit time, and venous microvascular transit time.

Results—

Microvascular density and diameter were significantly increased in MMD patients (1.8±0.2 mm/mm
2
and 0.24±0.03 mm, respectively) compared with those in ACVD patients (1.5±0.2 mm/mm
2
and 0.20±0.02 mm, respectively) and controls (1.5±0.1 mm/mm
2
and 0.19±0.03 mm, respectively). This resulted in significantly increased microvascular surface per analyzed area in MMD (67±13%) vs ACVD patients (47±7%) and controls (45±6%). Anatomic changes were paralleled by significantly increased microvascular and arterial microvascular transit times in MMD patients (11.55±3.50 and 6.79±2.96 seconds, respectively) compared with those in ACVD patients (8.13±1.78 and 4.34±1.30 seconds, respectively) and controls (8.04±2.16 and 4.50±1.87 seconds, respectively).

Conclusion—

Cortical microvascularization in MMD is characterized by significantly increased microvascular density and microvascular diameter, leading to increased microvascular surface. These anatomic alterations are accompanied by prolonged microvascular hemodynamics. These observations might represent an MMD-specific compensation mechanism for impaired cerebral blood flow.
Effects of Neuroglobin Overexpression on Acute Brain Injury and Long-Term Outcomes After Focal Cerebral Ischemia
Authors: Wang Xiaoying , Liu Jianxiang , Zhu Haihao , Tejima Emiri , Tsuji Kiyoshi , Murata Yoshihiro , Atochin Dmitriy N. , Huang Paul L. , Zhang Chenggang , Lo Eng H.
Published: April 2008

Background and Purpose—

Emerging data suggest that neuroglobin (Ngb) may protect against hypoxic/ischemic neuronal insults. However, the underlying mechanisms in vivo and implications for long-term outcomes are still not well understood.

Methods—

Using our newly created Ngb overexpressing transgenic (Ngb-Tg) mice, we measured brain infarction on day 1 and day 14 after transient focal cerebral ischemia and performed neurobehavioral assessments in sensorimotor deficits on days 1, 3, 7, and 14. To test the hypothesis that Ngb may play a role in reducing oxidative stress after stroke, intracellular malondialdehyde levels were measured and compared in Ngb-Tg and wild-type mice.

Results—

Increased Ngb mRNA and protein levels were identified in Ngb-Tg brains. Malondialdehyde levels in ischemic hemispheres of Ngb-Tg were significantly reduced compared with wild-type controls at 8 hours and 22 hours after transient focal cerebral ischemia. Compared with wild-type controls, brain infarction volumes 1 day and 14 days after transient focal cerebral ischemia were significantly reduced in Ngb-Tg mice. However, there were no significant improvements in sensorimotor deficits for up to 14 days after stroke in Ngb-Tg mice compared with wild-type controls.

Conclusions—

Ngb reduces tissue infarction and markers of oxidative stress after stroke. Tissue protection by overexpressing Ngb can be sustained for up to 2 weeks.
Polymorphisms in Platelet Glycoprotein 1bα and Factor VII and Risk of Ischemic Stroke
Authors: Maguire Jane M. , Thakkinstian Ammarin , Sturm Jon , Levi Christopher , Lincz Lisa , Parsons Mark , Whyte Scott , Attia John
Published: April 2008

Background and Purpose—

Platelets and components of the coagulation cascade are known to be instrumental in the pathogenesis of arterial occlusive disorders. The aim of this meta-analysis is to test the hypothesis that genetic variation in the platelet glycoprotein 1bα and Factor VII genes influence the occurrence of ischemic stroke. All genetic association studies that examined the R353Q (rs6046) polymorphism of the Factor VII gene and 2 polymorphisms of the platelet glycoprotein (1bα) gene (Thr/Met rs6065 and Kozak sequence −5 C/T rs2243093) in relation to ischemic stroke were examined.

Methods—

Electronic databases Embase, Medline, and HuGEnet were searched for all years up until June 2006 for all studies that evaluated any of these candidate genes and stroke.

Results—

Pooled ORs were calculated with 95% CIs using both fixed and random effects models. Meta-analysis for Factor VII (R353Q) did not detect any effect on ischemic stroke risk. Further estimation resulted in pooled OR
1
QQ versus RR=0.9 (95% CI: 0.4 to 1.9) and pooled OR
2
for RQ versus RR=0.9 (95% CI: 0.6 to 1.4). These results were robust and homogeneous. Pooling ORs for the platelet glycoprotein 1bα Kozak variant −5 T/C polymorphism showed extreme heterogeneity with differing effect directions across studies. Fisher’s method of pooling was therefore used to calculate a combined probability value, which was highly significant (
P
<0.001). The pooled OR for platelet glycoprotein 1bα Met/Met v Thr/Thr was 1.0 to 2.0, depending on the sensitivity analyses, and for Thr/Met versus Thr/Thr, the pooled OR was between 1.3 and 1.4. These results were consistent, reasonably robust, and implied a dominant genetic effect.

Conclusion—

This analysis provides strong evidence that the Factor VII R353Q gene polymorphism is not associated with ischemic stroke, that the Thr/Met polymorphism of GP1bα is associated with ischemic stroke in a dominant genetic model, and that the Kozak sequence polymorphism of GP1bα may be close to another causative locus that is associated with ischemic stroke.
Acute Stroke Imaging Research Roadmap
Authors: Wintermark Max , Albers Gregory W. , Alexandrov Andrei V. , Alger Jeffry R. , Bammer Roland , Baron Jean-Claude , Davis Stephen , Demaerschalk Bart M. , Derdeyn Colin P. , Donnan Geoffrey A. , Eastwood James D. , Fiebach Jochen B. , Fisher Marc , Furie Karen L. , Goldmakher Gregory V. , Hacke Werner , Kidwell Chelsea S. , Kloska Stephan P. , Köhrmann Martin , Koroshetz Walter , Lee Ting-Yim , Lees Kennedy R. , Lev Michael H. , Liebeskind David S. , Ostergaard Leif , Powers William J. , Provenzale James , Schellinger Peter , Silbergleit Robert , Sorensen Alma Gregory , Wardlaw Joanna , Wu Ona , Warach Steven
Published: April 2008

The recent “Advanced Neuroimaging for Acute Stroke Treatment” meeting on September 7 and 8, 2007 in Washington DC, brought together stroke neurologists, neuroradiologists, emergency physicians, neuroimaging research scientists, members of the National Institute of Neurological Disorders and Stroke (NINDS), the National Institute of Biomedical Imaging and Bioengineering (NIBIB), industry representatives, and members of the US Food and Drug Administration (FDA) to discuss the role of advanced neuroimaging in acute stroke treatment. The goals of the meeting were to assess state-of-the-art practice in terms of acute stroke imaging research and to propose specific recommendations regarding: (1) the standardization of perfusion and penumbral imaging techniques, (2) the validation of the accuracy and clinical utility of imaging markers of the ischemic penumbra, (3) the validation of imaging biomarkers relevant to clinical outcomes, and (4) the creation of a central repository to achieve these goals. The present article summarizes these recommendations and examines practical steps to achieve them.