bluuebunny/crossref_metadata_2025 huggingface dataset:
CD47 and TLR-2 Cross-Talk Regulates Neutrophil Transmigration
Authors: Chin Alex C. , Fournier Bénédicte , Peatman Eric J. , Reaves Titus A. , Lee Winston Y. , Parkos Charles A.
Published: October 2009

Neutrophil (PMN) infiltration into tissues is a hallmark of acute inflammation and is crucial for the rapid removal of microbial pathogens. Previous studies have shown that PMN transmigration is regulated by the cell surface protein CD47. However this phenomenon in the context of microbial invasion and subsequent TLR signaling is poorly understood. In this study, we assessed the role of TLR2 and CD47 costimulation in regulating PMN transmigration. Human PMN transmigration across acellular collagen-coated filters toward the bacterial chemoattractant fMLP was more significantly inhibited by MALP-2 (TLR2/6 agonist) than Pam3CSK4 (TLR2/1 agonist). Subsequent experiments demonstrated that treatment with MALP-2 or anti-human CD47 mAbs delayed human PMN transfilter migration, while combined treatment led to further delayed inhibition. Interestingly, stimulation of PMNs with MALP-2 resulted in an increase in surface expression of CD11b, but not CD47. In experiments addressing the role of TLR agonists in regulating CD47-mediated PMN transmigration, incubation with MALP-2 or with anti-mouse CD47 mAbs did not inhibit transfilter migration of TLR2−/− or MyD88−/−-deficient murine bone marrow-derived PMNs. Similarly, inhibition of MyD88 homodimerization reversed the attenuation of human PMN transmigration induced by MALP-2 or anti-human CD47 mAbs. Separate experiments demonstrated that CD47−/− murine bone marrow-derived PMNs exhibited 4-fold decreased sensitivity toward MALP-2. Collectively, these findings suggest that activation of CD47 signaling enhances PMN sensitivity toward TLR2 activation which, in turn, signals their arrival at a site of invasion and may facilitate antimicrobial function.
Expulsion of Secondary Trichinella spiralis Infection in Rats Occurs Independently of Mucosal Mast Cell Release of Mast Cell Protease II
Authors: Blum Lisa K. , Thrasher Seana M. , Gagliardo Lucille F. , Fabre Valeria , Appleton Judith A.
Published: October 2009

Our aim was to elucidate the contribution of mucosal mast cells to the effector phase of a secondary immune response to Trichinella spiralis. During secondary infection, rats expel 90–99% of T. spiralis first-stage larvae from the intestine in a matter of hours. This phenomenon appears to be unique to rats and has been called rapid expulsion. Primary intestinal infection by T. spiralis induces mastocytosis, and mast cell degranulation occurs when challenged rats exhibit rapid expulsion. These observations have engendered the view that mast cells mediate rapid expulsion. In this study, we report that. immunization of adult Albino Oxford rats by an infection limited to the muscle phase did not induce intestinal mastocytosis, yet such rats exhibited rapid expulsion when challenged orally. Although mastocytosis was absent, the protease unique to mucosal mast cells, rat mast cell protease II (RMCPII), was detected in sera at the time of expulsion. We further evaluated mast cell activity in neonatal rats that display rapid expulsion. Pups born to infected dams displayed rapid expulsion, and RMCPII was detected in their sera. By feeding pups parasite-specific mAbs or polyclonal Abs before challenge infection, it was possible to dissociate mast cell degranulation from parasite expulsion. These results indicate that rapid expulsion can occur in the absence of either intestinal mastocytosis or RMCPII release. Furthermore, release of RMCPII is not sufficient to cause expulsion. The data argue against a role for mast cells in the mechanism underlying the effector phase of protective immunity against T. spiralis in rats.
Regulation of Gastric B Cell Recruitment Is Dependent on IL-17 Receptor A Signaling in a Model of Chronic Bacterial Infection
Authors: Algood Holly M. Scott , Allen Shannon Sedberry , Washington Mary K. , Peek Richard M. , Miller Geraldine G. , Cover Timothy L.
Published: October 2009

Th17-driven immune responses contribute to the pathogenesis of many chronic inflammatory diseases. In this study, we investigated the role of IL-17 signaling in chronic gastric inflammation induced by Helicobacter pylori, a Gram-negative bacterium that persistently colonizes the human stomach. Wild-type C57BL/6 mice and mice lacking IL-17RA (IL-17RA−/−) were orogastrically infected with H. pylori. Differences in bacterial colonization density and gastric inflammation were not apparent at 1 mo postinfection, but by 3 mo postinfection, H. pylori colonization density was higher and mononuclear gastric inflammation more severe in infected IL-17RA−/− mice than in infected wild-type mice. A striking feature was a marked increase in gastric B cells, plasma cells, and lymphoid follicles, along with enhanced H. pylori-specific serum Ab responses, in infected IL-17RA−/− mice. Fewer gastric neutrophils and lower levels of neutrophil-recruiting chemokines were detected in infected IL-17RA−/− mice than in infected wild-type mice. Gastric IL-17a and IL-21 transcript levels were significantly higher in infected IL-17RA−/− mice than in infected wild-type mice or uninfected mice, which suggested that a negative feedback loop was impaired in the IL-17RA−/− mice. These results underscore an important role of IL-17RA signaling in regulating B cell recruitment. In contrast to many chronic inflammatory diseases in which IL-17RA signaling promotes an inflammatory response, IL-17RA signaling down-regulates the chronic mononuclear inflammation elicited by H. pylori infection.
Human Cathelicidin Peptide LL-37 Modulates the Effects of IFN-γ on APCs
Authors: Nijnik Anastasia , Pistolic Jelena , Wyatt Aaron , Tam Sheena , Hancock Robert E. W.
Published: October 2009

The human cathelicidin peptide LL-37 is a multifunctional immunomodulatory and antimicrobial host defense peptide of the human immune system. LL-37 modulates host cell responses to microbial stimuli and also affects the action of other endogenous immune mediators such as IL-1β and GM-CSF. This activity of LL-37 is known to be complex, with the functional outcomes being dependent on the cell type and activation status, timing of exposure, and other immune mediators present. It was demonstrated in this study that LL-37 inhibited cellular responses to IFN-γ, the key cytokine of Th1-polarized immunity. The inhibitory activity of LL-37 on IFN-γ responses was characterized in monocytes, macrophages, dendritic cells, and B lymphocytes, showing suppression of cell activation, proliferation, and production of proinflammatory and Th1-polarizing cytokines, and Abs. It was further shown that in monocytes the suppressive effects of LL-37 were mediated through inhibition of STAT1-independent signaling events, involving both the p65 subunit of NF-κB and p38 MAPK. This study suggests that LL-37 modulates IFN-γ responses during both the innate and adaptive phases of immune responses, indicating a new immunomodulatory role for this endogenous peptide. These effects on IFN-γ activity should be taken into consideration in the development of cathelicidin-based peptides for therapeutic applications as immunomodulatory or microbicidal agents.
Doxorubicin-induced cardiotoxicity in adult Indian patients on chemotherapy
Authors: Khattry Navin , Malhotra Pankaj , Grover Anil , Sharma Suresh K , Varma Subhash
Published: October 2009

Background:Doxorubicin-induced cardiotoxicity is widely known to occur at cumulative doses exceeding 450 mg/m2 . However, very few studies have reported incidence of cardiac dysfunction in patients on chemotherapy with lower cumulative doses. To the best of our knowledge, there is no study carried out so far that has reported the incidence of cardiac dysfunction in adult Indian patients receiving doxorubicin. This study was undertaken to determine the incidence of doxorubicin-induced cardiotoxicity by serial resting echocardiography in patients on chemotherapy and identify risk factors associated with cardiotoxicity.Materials and Methods:Patients that were started on doxorubicin-based chemotherapy in the period from January 2000 to June 2001 and had completed at least 300 mg/m2cumulative dose were taken in the study. Electrocardiography, chest X-ray and echocardiography were done at baseline, at 300 mg/m2and at 450 mg/m2cumulative doses of doxorubicin. All patients were evaluated for the presence of the following risk factors:Age>70 years, female sex, preexisting cardiac disease, hypertension, chest wall irradiation, body mass index (BMI)< 20 kg/m2 , Karnofsky performance status, combination chemotherapy with cyclophosphamide and presence of liver disease. Subclinical cardiac dysfunction was defined as ejection fraction fall greater than 10% on follow-up echocardiography.Results:Thirty patients satisfied the criterion for being considered for evaluation. One (3%) patient developed congestive cardiac failure, while 8 (27%) patients developed subclinical cardiac dysfunction. Concomitant use of cyclophosphamide significantly increased the risk of cardiac dysfunction ( P=0.048), while low BMI (< 20 kg/m2 ) and preexisting cardiac disease showed a trend towards increased risk of cardiac dysfunction ( P=0.07 for both).Conclusion:Twenty-seven percent of the patients developed subclinical cardiac dysfunction in the cumulative dose range of 300-450 mg/m2 . This entails regular monitoring for cardiac dysfunction by echocardiography during treatment.
Ovarian lymphoma
Authors: Crasta Julian A , Vallikad Elizabeth
Published: October 2009

The involvement of the ovary in lymphomatous processes is rare. Such an involvement can occur in 2 ways, either primary or secondary, which usually presents with abdominal or pelvic complaints. We present a case of secondary involvement of the ovary with occult extra-ovarian nodal disease and discuss the histogenesis of ovarian lymphomas with criteria for diagnosis and differential diagnosis.
Melorheostosis with renal arterio-venous malformation: A case report with review of literature
Authors: Lone Abdul Rashid , Ahmad Mushtaq , Aziz Sheikh Aejaz , Bhat Gul Mohammad , Bhat Javid Rasool , Jahan Rifat , Khan Shoukat H
Published: October 2009

Melorheostosis, also known as Leri′s disease and flowing periosteal hyperostosis, is a rare cause of pain and stiffness in a limb. The appearance is of "candle greasing" down one side of one or several bones of the body. We describe a case referred to tertiary care center with suspicion of renal cell carcinoma with diffuse bone metastasis. After reassessment, the patient was diagnosed melorheostosis with renal AV malformation. He was reassured about the benign nature of the disease and is asymptomatic.
Thermochemical Nanolithography of Multifunctional Nanotemplates for Assembling Nano‐Objects
Authors: Wang Debin , Kodali Vamsi K. , Underwood II William D. , Jarvholm Jonas E. , Okada Takashi , Jones Simon C. , Rumi Mariacristina , Dai Zhenting , King William P. , Marder Seth R. , Curtis Jennifer E. , Riedo Elisa
Published: October 2009

Nanoscale chemical patterning of different chemical species (amine, thiol, aldehyde, and biotin) in independent nanopatterns is achieved by the iterative application of thermochemical nanolithography (TCNL) to inscribe amine patterns followed by their chemical conversion to other functional groups. Due to the unique chemical stability of the patterns, the resultant substrates can be stored for weeks and subsequently be used for covalent and molecular‐recognition‐based attachment of nano‐objects using standard chemical protocols. In particular, the ability of this method to attach proteins and DNA to the chemical nanopatterns and to create co‐patterns of two distinctive bioactive proteins is demonstrated.
Efficiency Enhancement in Organic Photovoltaic Cells: Consequences of Optimizing Series Resistance
Authors: Servaites Jonathan D. , Yeganeh Sina , Marks Tobin J. , Ratner Mark A.
Published: October 2009

Here, means to enhance power conversion efficiency (PCE or η) in bulk‐heterojunction (BHJ) organic photovoltaic (OPV) cells by optimizing the series resistance (Rs)—also known as the cell internal resistance—are studied. It is shown that current state‐of‐the‐art BHJ OPVs are approaching the limit for which efficiency can be improved via Rs reduction alone. This evaluation addresses OPVs based on a poly(3‐hexylthiophene):6,6‐phenyl C61‐butyric acid methyl ester (P3HT:PCBM) active layer, as well as future high‐efficiency OPVs (η > 10%). A diode‐based modeling approach is used to assess changes in Rs. Given that typical published P3HT:PCBM test cells have relatively small areas (∼0.1 cm2), the analysis is extended to consider efficiency losses for larger area cells and shows that the transparent anode conductivity is then the dominant materials parameter affecting Rs efficiency losses. A model is developed that uses cell sizes and anode conductivities to predict current–voltage response as a function of resistive losses. The results show that the losses due to Rs remain minimal until relatively large cell areas (>0.1 cm2) are employed. Finally, Rs effects on a projected high‐efficiency OPV scenario are assessed, based on the goal of cell efficiencies >10%. Here, Rs optimization effects remain modest; however, there are now more pronounced losses due to cell size, and it is shown how these losses can be mitigated by using higher conductivity anodes.
Complementary and alternative medicine use among long‐term lymphoma survivors: A pilot study
Authors: Habermann Thomas M. , Thompson Carrie A. , LaPlant Betsy R. , Bauer Brent A. , Janney Carol A. , Clark Matthew M. , Rummans Teresa A. , Maurer Matthew J. , Sloan Jeff A. , Geyer Susan M. , Cerhan James R.
Published: October 2009

No published survey has specifically addressed the beliefs, knowledge, and usage of complementary and alternative medicine (CAM) in long‐term (5–20 years) lymphoma survivors alone. In this pilot project, 95 subjects were randomly selected from a population of 2,475 long‐term lymphoma survivors and mailed a questionnaire. The median time from lymphoma diagnosis to completion of the questionnaire was 11 years (range 6–20). Overall, 68% (95% CI: 54–80%) of the long‐term lymphoma survivors reported that they have used CAM, a rate higher than the estimated usage rate reported for the general population The most commonly used modalities were chiropractic (39%, 95% CI: 27–53%) and massage therapy (21%, 95% CI: 12–34%). Less than 10% used meditation (5%, 95% CI: 1–15%) and relaxation (7%, 95% CI: 2–17%). In terms of common herbal usage, 5% (95% CI: 1–15%) had used St. John's Wort and 7% (95% CI: 2–17%) had used shark cartilage. Although none of the patients reported that CAM usage was directed specifically towards treating their lymphoma, 4% (95% CI: 0–12%) of patients reported that CAM could cure cancer, and 14% (95% CI: 6–26%) reported that CAM could increase their feeling of control over their health. This pilot study suggests that long‐term lymphoma survivors appear to use CAM at a rate higher than the general population. The use of potential agents of risk by the survivors and the lack of access to potentially beneficial modalities highlights the need for further study of CAM in this population. Am. J. Hematol., 2009. © 2009 Wiley‐Liss, Inc.
Outcome of 93 patients with relapse or progression following allogeneic hematopoietic cell transplantation
Authors: Kurosawa Saiko , Fukuda Takahiro , Tajima Kinuko , Saito Bungo , Fuji Shigeo , Yokoyama Hiroki , Kim Sung‐Won , Mori Shin‐Ichiro , Tanosaki Ryuji , Heike Yuji , Takaue Yoichi
Published: October 2009

Relapse/progression after allogeneic hematopoietic cell transplantation (allo‐HCT) remains the major cause of treatment failure. In this study, the subsequent clinical outcome was overviewed in 292 patients with leukemia/myelodysplastic syndrome who received allo‐HCT. Among them, 93 (32%) showed relapse/progression. Cohort 1 was chosen to receive no interventions with curative intent (n = 25). Cohort 2 received reinduction chemotherapy and/or donor lymphocyte infusion (n = 48), and Cohort 3 underwent a second allo‐HCT (n = 20). Sixty‐three patients received reinduction chemotherapy, and 27 (43%) achieved subsequent complete remission (CR). The incidence of nonrelapse mortality (NRM) was similar among the three cohorts (4, 15, and 5%). The 1‐year overall survival (OS) after relapse was significantly better in patients with a second HCT (58%) than in others (14%, Cohorts 1 and 2; P <.001). However, the 2‐year OS did not differ between the two groups, which suggests that it is difficult to maintain CR after the second HCT. Multivariate analysis showed that reinduction chemotherapy, CR after intervention, second HCT, and longer time to post‐transplant relapse were associated with improved survival. In conclusion, for patients with relapse after allo‐HCT, successful reinduction chemotherapy and a second HCT may be effective for prolonging survival without excessive NRM. However, effective measures to prevent disease progression after a second HCT clearly need to be developed. Am. J. Hematol. 2009. © 2009 Wiley‐Liss, Inc.
Polymorphisms of drug‐metabolizing genes and risk of non‐Hodgkin lymphoma
Authors: Kim Hee Nam , Kim Nan Young , Yu Li , Kim Yeo‐Kyeoung , Lee Il‐Kwon , Yang Deok‐Hwan , Lee Je‐Jung , Shin Min‐Ho , Park Kyeong‐Soo , Choi Jin‐Su , Kim Hyeoung‐Joon
Published: October 2009

Drug metabolizing genes are involved in the detoxification of chemical carcinogens. Polymorphisms in drug‐metabolizing genes affect the risk of some forms of cancer. We analyzed six polymorphisms to evaluate their association with risk for non‐Hodgkin lymphoma (NHL), and to examine whether smoking modifies these associations in population‐based study in Korea (713 cases and 1,700 controls). The GSTP1 rs1695 AG and the combined AG/GG genotypes were associated with decreased risk of NHL (odds ratio (OR)AG = 0.67, 95% confidence interval (CI) = 0.55–0.82; ORAG/GG = 0.66, 95% CI = 0.54–0.80) and DLBCL (ORAG = 0.63, 95% CI = 0.49–0.82; ORAG/GG = 0.64, 95% CI = 0.50–0.82). For T‐cell lymphoma, only the combined AG/GG genotype was associated with decreased risk (ORAG/GG = 0.65, 95% CI = 0.44–0.96). The CYP1A1 rs1048943 AG genotype and the combined AG/GG genotypes were associated with increased risk of NHL (ORAG = 1.28, 95% CI = 1.07–1.54; ORAG/GG = 1.26, 95% CI = 1.06–1.51) and DLBCL (ORAG = 1.32, 95% CI = 1.04–1.66; ORAG/GG = 1.30, 95% CI = 1.03–1.63), but not T‐cell lymphoma. Smoking does not modify the association between these polymorphisms and NHL risk. Our data provide evidence that the GSTP1 rs1695 and the CYP1A1 rs1048943 genotypes affect the risk of NHL in Korea. Am. J. Hematol. 2009. © 2009 Wiley‐Liss, Inc.
White biotechnology for cellulose manufacturing—The HoLiR concept
Authors: Kralisch Dana , Hessler Nadine , Klemm Dieter , Erdmann Rainer , Schmidt Wolfgang
Published: October 2009

A variety of approaches are available for generation of bacteria‐produced nanocellulose (BNC) in different forms. BNC production under static cultivation conditions usually results in fleeces or foils, characterized by a homogeneous, three‐dimensional network of nanofibers and a uniform surface. However, under static cultivation conditions in batch vessels, the widths and the lengths of the BNC sheets cultured are determined by the dimensions of the culture vessel. In this contribution, a novel, efficient process for a (semi‐)continuous cultivation of planar BNC fleeces and foils with a freely selectable length and an adjustable height is presented. By means of comprehensive investigations, the comparability of the BNC harvested to that gained from static cultivation under batch conditions is demonstrated. A first estimation of the production costs further shows that this type of processing allows for significant cost reductions compared to static cultivation of BNC in Erlenmeyer flasks. Biotechnol. Bioeng. 2010. 105: 740–747. © 2009 Wiley Periodicals, Inc.
Control of Lipase Enantioselectivity by Engineering the Substrate Binding Site and Access Channel
Authors: Lafaquière Vincent , Barbe Sophie , Puech‐Guenot Sophie , Guieysse David , Cortés Juan , Monsan Pierre , Siméon Thierry , André Isabelle , Remaud‐Siméon Magali
Published: October 2009

Lipase from Burkholderia cepacia (BCL) has proven to be a very useful biocatalyst for the resolution of 2‐substituted racemic acid derivatives, which are important chiral building blocks. Our previous work showed that enantioselectivity of the wild‐type BCL could be improved by chemical engineering of the substrate's molecular structure. From this earlier study, three amino acids (L17, V266 and L287) were proposed as targets for mutagenesis aimed at tailoring enzyme enantioselectivity. In the present work, a small library of 57 BCL single mutants targeted on these three residues was constructed and screened for enantioselectivity towards (R,S)‐2‐chloro ethyl 2‐bromophenylacetate. This led to the fast isolation of three single mutants with a remarkable tenfold enhanced or reversed enantioselectivity. Analysis of substrate docking and access trajectories in the active site was then performed. From this analysis, the construction of 13 double mutants was proposed. Among them, an outstanding improved mutant of BCL was isolated that showed an E value of 178 and a 15‐fold enhanced specific activity compared to the parental enzyme; thus, this study demonstrates the efficiency of the semirational engineering strategy.
CH Functionalizations by Means of Direct Borane–Hydrocarbon Dehydrogenations and Dehydrocarbonations
Authors: Goldfuss Bernd
Published: October 2009

The CH functionalization of methane by means of direct CH borations with BH3 or MeBH2 is compared computationally (using the B3LYP/6‐311++G** method) to CH lithiations with LiH or LiMe as well as to other analogue C–metal (Be, Na, Mg, Al) formations. For the borations only, this internal electrophilic substitution at carbon (SEi) relies more on the electrophilicity of boron than on the basicity of the internal base Y, that is, H or Me. Such direct borations of methane are more favored for dehydrogenations than for dehydrocarbonations. Due to decreased electrophilicity, substituents at boron disfavor such borations. Hence, the BH2 group appears to be most efficient for CH functionalizations by means of direct hydrocarbon borations.
Gewinnung eines partialglyceridhaltigen Biokraftstoffs durch enzymatische Teilethanolyse von Pflanzenöl
Authors: Stäbler A. , Menner M. , Eisner P.
Published: October 2009

Die Bedeutung pflanzenölbasierter Kraftstoffe, insbesondere von Biodiesel, steigt ständig an. Allerdings weisen gängige Verfahren zur Biodieselherstellung gravierende Nachteile auf, wie ein aufwendiges Downstream Processing und eine geringe Kraftstoffausbeute. Der vorliegende Artikel beschreibt grundlegende Arbeiten zur Herstellung eines neuartigen, partialglyceridhaltigen Biokraftstoffes mittels sn‐1,3‐regiospezifischen Lipasen. Bei diesem nebenproduktfreien Verfahren wird eine nahezu vollständige Kraftstoffausbeute erreicht. Eine Aufreinigung des Produktes entfällt.
Persistent Troponin Elevation in a Patient with Cardiac Amyloidosis
Authors: Kraemer Bjoern F. , Seizer Peter , Geisler Tobias , Klingel Karin , Kandolf Reinhard , Lindemann Stephan , Gawaz Meinrad
Published: October 2009

A 79‐year‐old patient repeatedly presented with chest discomfort and dyspnea on exertion. With echocardiography a prominent left ventricular and septal hypertrophy was detected with reduced left ventricular function. Despite successful revascularization and excellent results after stenting, the patient showed persistently elevated troponin levels. To investigate the abnormal findings of persistent troponin elevation, septal hypertrophy, and heart failure we performed endomyocardial biopsies which showed widespread myocardial amyloidosis. Amyloid subtyping revealed transthyretin amyloidosis. This is the first case showing persistent troponin elevation in a patient with tranthyretin amyloidosis. Very few other cases have been published on the topic of cardiac amyloidosis and troponin elevation so far. Our case serves as an illustrating example in the differential diagnosis of nonischemic causes of persistent troponin elevation. It is important to consider cardiac amyloidosis in patients with troponin elevation and heart failure since the clinical management differs significantly from other causes of heart failure. Copyright © 2009 Wiley Periodicals, Inc.
Traumatic Brachiocephalic Pseudoaneurysm Presenting as Stroke in a Seventeen‐Year‐Old
Authors: Kanwar Manreet , Desai Devang , Joumaa Mouhammed , Guduguntla Vamshidhar
Published: October 2009

We present a 17‐y‐old male who presented to the emergency room with left arm weakness along with slurred speech. On physical examination, he had stable vital signs with left facial weakness suggestive of lower motor neuron seventh nerve palsy. He was also noted to have a small pulsatile mass in the right infraclavicular region. Further questioning revealed that 3 mo earlier he had suffered blunt chest wall trauma during a football game with fracture–dislocation of the right clavicular head, which was managed conservatively. MRI of the brain showed right frontal cortical changes suggestive of infarct versus vasculitis or edema. Chest CT revealed a 2.5‐ to 3‐cm pseudoaneurysm arising from the brachiocephalic artery, with thrombus formation, along with a surrounding 3 × 4.5 cm hematoma. The patient underwent a successful repair of the pseudoaneurysm with no further neurological sequelae. Traumatic pseudoaneurysm with thrombus formation is an extremely rare cause of stroke. It has been reported in association with the carotid artery, but to our knowledge, this is the first reported case with isolated innominate artery pseudoaneurysm. This case highlights the need for a broad differential when evaluating young patients with neurological deficits. Copyright © 2009 Wiley Periodicals, Inc.
Anatomical Factors Triggering Platypnea‐Orthodeoxia in Adults
Authors: Sanikommu Vijaya , Lasorda David , Poornima Indu
Published: October 2009

Right to left shunting through a patent foramen ovale (PFO) or atrial septal defect (ASD) can cause platypnea‐orthodeoxia even in a setting of normal pulmonary artery pressures. However, the late onset of symptoms despite the congenital origin of the anatomical defects is not well understood. We report a case series of patients presenting with dyspnea and orthodeoxia who developed right to left shunting as a result of associated anatomical changes that occur with aging such as tortuosity and elongation of the aorta. We propose that these acquired anatomical changes can favor right to left shunting in the setting of congenital abnormalities, therefore explaining the late onset of symptoms. Copyright © 2009 Wiley Periodicals, Inc.
Association of Cystatin C with Ischemia in Patients with Coronary Heart Disease
Authors: Deo Rajet , Shlipak Michael G. , Ix Joachim H. , Ali Sadia , Schiller Nelson B. , Whooley Mary A.
Published: October 2009

Background

Elevated concentrations of cystatin C are associated with greater cardiovascular morbidity and mortality. We sought to determine whether elevated concentrations of cystatin C were associated with inducible ischemia in patients with coronary heart disease (CHD).

Methods

We measured serum cystatin C and performed exercise treadmill testing with stress echocardiography in a cross‐sectional study of 899 outpatients with CHD.

Results

Among the 241 participants in the highest quartile of cystatin C (>1.30 mg/L), 38% had inducible ischemia, compared with 13% of those in the lowest quartile of cystatin C < 0.92 mg/L; adjusted odds ratio [OR]: 2.1; 95% confidence interval [CI]: 1.2 to 3.8; p = 0.01). However, this association differed in participants with and without a history of coronary artery bypass graft (CABG), as well as in users and nonusers of beta‐blockers and statins (p values for interaction < 0.1). Among participants without a history of CABG, 35% of those in the highest quartile and 9% of those in the lowest quartile of cystatin C had inducible ischemia (adjusted OR: 3.05; 95% CI: 1.3–6.9; p = 0.008). Among participants who were not using beta‐blockers, 44% of those in the highest quartile and 7% in the lowest quartile of cystatin C had inducible ischemia (adjusted OR: 5.3; 95% CI: 1.8–15.5; p = 0.002). Among participants who were not using statins, 39% of participants in the highest quartile and 4% of those in the lowest quartile had inducible ischemia (adjusted OR: 10.3; 95% CI: 2.5–43.3; p = 0.001).

Conclusions

Elevated levels of cystatin C are independently associated with inducible ischemia among outpatients with stable coronary disease. Copyright © 2009 Wiley Periodicals, Inc.
Nonapical Tako‐tsubo Cardiomyopathy Associated with Coronary Slow Flow: A Case Report and Review of the Literature
Authors: Krishnan Unni , Zacharzewski Amanda , Schmitt Matthias
Published: October 2009

The exact pathophysiology of tako‐tsubo cardiomyopathy (TTC) is unclear. A nonapical form of TTC precipitated by emotional stress is presented. Findings on 12 lead ECG and coronary angiogram are discussed. The role of specialized investigations such as cardiac MRI and tissue Doppler imaging are reviewed. We then examine the probable molecular explanations for this condition and suggest a probable molecular mechanism based on animal studies. Future therapeutic options are also briefly discussed. Copyright © 2009 Wiley Periodicals, Inc.
ST Deviation Pattern and Infarct Related Artery in Acute Myocardial Infarction
Authors: Rott David , Nowatzky Johannes , Teddy Weiss A. , Chajek‐Shaul Tova , Leibowitz David
Published: October 2009

Background

Myocardial infarction (MI) may be classified as ST‐elevation MI (STEMI) or non‐ST‐elevation MI (NSTEMI). There is little data regarding the relationship between the infarct related artery (IRA), clinical characteristics of the patients, and the ST deviation pattern (ie, STEMI or NSTEMI).

Hypothesis

There is a predilection of any coronary artery to a particular ST deviation pattern of acute MI.

Methods

We reviewed our institutional database and selected patients who presented with an acute MI and underwent coronary angiography within 7 days of admission. The analysis included 830 patients of whom 563 had STEMI and 267 had NSTEMI. The culprit lesion was defined by reviewing each patient's angiographic report, electrocardiogram, and echocardiogram. TIMI flow rate was determined.

Results

The IRA in STEMI was most frequently the left anterior descending coronary artery (LAD) followed by the right coronary artery (RCA) and then the left circumflex coronary artery (LCX), a statistically significant difference. In patients with NSTEMI there were no significant differences in IRA. Patients with STEMI and LCX as the IRA were significantly younger and had a higher percentage of TIMI grade 3 flow then patients with STEMI and LAD or RCA as IRAs. These differences were not noted in patients with NSTEMI regardless of IRA.

Conclusions

In STEMI there were significant differences in age and TIMI flow depending on the IRA. These findings were not demonstrated in patients with NSTEMI. Copyright © 2009 Wiley Periodicals, Inc.
Appearance of Electrocardiographic Initial U‐Wave Inversion Dependent on Pressure‐Induced Early Diastolic Impairment in Patients with Hypertension
Authors: Miwa Kunihisa
Published: October 2009

Background

ECG U‐wave inversion can be classified as initial and terminal U inversion according to the phasic relationship to positive U‐wave deflection. Initial U inversion is occasionally observed in hypertensive patients while terminal U inversion frequently appears during severe myocardial ischemia.

Hypothesis

The genesis of initial U inversion may be related to pressure‐induced diastolic dysfunction.

Methods

In order to clarify the genesis of initial U‐wave inversion we studied 11 consecutive hypertensive patients with both initial U inversion and impaired left ventricular early relaxation who were evaluated using Doppler echocardiography.

Results

The U inversion disappeared during acute pressure lowering by sublingual administration of nitroglycerin. The U inversion also disappeared and relaxation improved significantly after chronic blood pressure lowering. Initial U inversion reappeared during a cold pressor test.

Conclusion

The appearance of initial U inversion was dependent on the pressure‐induced impaired left ventricular early relaxation in hypertensive patients. Copyright © 2009 Wiley Periodicals, Inc.
A Combined Experimental and Theoretical Study on the Magnetic Properties of a Family of Bis(μ‐phenoxido)dicopper(II) Complexes Bearing ω‐[Bis(2‐hydroxy‐3,5‐dimethylbenzyl)amino]alkan‐1‐ol Ligands
Authors: Wichmann Oula , Sopo Harri , Colacio Enrique , Mota Antonio J. , Sillanpää Reijo
Published: October 2009

Five new neutral bis(μ‐phenoxido)dicopper(II) complexes, [Cu2(μ‐HL1)2]·3EtOH·H2O (1), [Cu2(μ‐HL2)2]·1.65H2O (2), [Cu2(μ‐HL3)2(μ‐H2O)] (3), [Cu2(μ‐HL4)2] (4) and [Cu2(μ‐HL5)2(μ‐H2O)] (5), were prepared from a family of ω‐[bis(2‐hydroxy‐3,5‐dimethylbenzyl)amino]alkan‐1‐ol ligands (H3L1–H3L5 derived from 2‐aminoethanol, 3‐aminopropanol, 4‐aminobutanol, 5‐aminopentanol and 6‐aminohexanol, respectively) bearing a [O,N,O,O′] donor set. In complexes 3 and 5, there is also a bridging water molecule between the metallic centres. The copper(II) coordination planes of all these complexes form a roof‐like structure (the bridging O atoms are located at the top of the roof). The structural differences found for the different complexes and their relation with the magnetic properties is discussed below. Magnetic studies of these dinuclear complexes showed that J values vary from –470.8 to –91.2 as the Cu–O–Cu angles (θ) vary from 100.66(9) to 92.76(7)°. DFT theoretical calculations produced the corresponding magnetic exchange coupling constants, finding that these values are quite near to the experimental ones. A linear relationship between the calculated J values and θ was observed, clearly supporting that the major factor controlling the magnetic exchange coupling in this series of complexes is, by far, the Cu–O–Cu bridging angle. The crossover point below which the magnetic behaviour changes from antiferromagnetic to ferromagnetic coupling is predicted at ≈ 89°. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2009)
Theoretical Analysis of the Possible Intermediates in the Formation of [W6O19]2–
Authors: Vilà‐Nadal Laia , Rodríguez‐Fortea Antonio , Poblet Josep M.
Published: October 2009

The structural features and the dynamic behaviour of different possible intermediates in the formation of the Lindqvist anion, [W6O19]2–, according to the stoichiometries observed in electrospray fragmentation experiments, were analyzed by DFT calculations. Two different and complementary techniques were used to take into account the effect of the solvent in the computations: (i) continuum solvation models and (ii) Car–Parrinello simulations with explicit solvent molecules. The interaction of the WVI ions with the nucleophilic water molecules expands their coordination sphere, reaching in many cases octahedral coordination. Furthermore, a common structural motif (“building block”) is observed in the most stable structures of the intermediates with higher nuclearities. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2009)
Aluminium Triflate Catalysed Cyclisation of Unsaturated Alcohols: Novel Synthesis of Rose Oxide and Analogues
Authors: Coulombel Lydie , Weïwer Michel , Duñach Elisabet
Published: October 2009

Aluminium trifluoromethanesulfonate was used as an efficient catalyst for the cycloisomerisation of several unsaturated alcohols into cyclic ethers such as rose oxide and some of its ether analogues. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2009)
Supramolecular Photochirogenesis with Carbenes Entrapped in Cyclodextrins
Authors: Mieusset Jean‐Luc , Wagner Gerald , Su Kuan‐Jen , Steurer Marianne , Pacar Mirjana , Abraham Michael , Brinker Udo H.
Published: October 2009

Two achiral diazirines 1a and 1b have been encapsulated in the inherently chiral cavity of α‐cyclodextrin (6‐Cy), β‐cyclodextrin (7‐Cy) and permethylated β‐cyclodextrin (TRIMEB) and photolyzed. Because of supramolecular photochirogenesis the generated carbenes afford intramolecular C–H insertion products not as a racemate but one enantiomer is slightly favored. With 1a@(6‐Cy)2 the ee of product 7a is doubled. To the best of our knowledge for the first time for carbene reactions, products are imprinted, though modestly, with handedness derived from Cys. The reaction of 1b is highly dependent on the molecular reactor used for inclusion. Whereas 7‐Cy is very efficient for favoring dimerization through azine formation, the use of TRIMEB permits exclusive formation of intramolecular insertion product 7b. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2009)
The Comparison of Electrochemical Assay and Agarose Gel Electrophoresis for the Determination of DNA Damage Induced by Kainic Acid
Authors: Karadeniz Hakan , Armagan Guliz , Erdem Arzum , Turunc Ezgi , Caliskan Ayfer , Kanit Lutfiye , Yalcin Ayfer
Published: October 2009

A possible DNA damage after interaction of kainic acid (KA) with calf thymus double stranded DNA and genomic DNA was herein determined in in vitro and in vivo conditions using; electrochemical assay and agarose gel electrophoresis. The changes in guanine signal were detected as an indicator of DNA damage in genomic DNA samples isolated from 1 or 10 mg/kg KA‐treated animals. The decreased levels of guanine signal were found as 29% and 33% by 1 and 10 mg/kg KA treatment when compared to controls, respectively. The results of gel electrophoresis confirmed DNA damage obtained in identical samples by electrochemical method.
Electrochemiluminescence of CdSe Quantum Dots Composited with Nitrogen‐Doped Carbon Nanotubes
Authors: Guo Liang , Liu Xuan , Hu Zheng , Deng Shengyuan , Ju Huangxian
Published: October 2009

A nanocomposite of CdSe quantum dots with nitrogen‐doped carbon nanotubes was prepared for enhancing the electrochemiluminescent (ECL) emission of quantum dots. With hydrogen peroxide as co‐reactant, the nanocomposite modified electrode showed a cathodic ECL emission with a starting potential of −0.97 V (vs. Ag/AgCl) in phosphate buffer solution, which was five‐times stronger than that from pure CdSe quantum dots and three‐times stronger than that from CdSe quantum dots composited with carbon nanotubes. The latter showed a starting potential of −1.19 V. This result led to a sensitive ECL sensing of hydrogen peroxide with good stability, acceptable reproducibility and a detection limit down to 2.1×10−7 mol L−1. Nitrogen‐doped carbon nanotubes could be used as a good material for the construction of sensitive ECL biosensors for chemical and biochemical analysis.
Epinephrine Oxidation in the Presence of Interfering Molecules on Gold and Gold Electrodes modified with Gold Nanoparticles and Thiodipropionic Acid in Aqueous Solution. A Comparative Study
Authors: Łuczak Teresa
Published: October 2009

Thiodipropionoc acid (TDPA), cysteamine (CA) and gold nanoparticles (Au‐NPs) modified gold pure electrodes have been applied in voltammetric sensors for simultaneous detection of epinephrine (EP), ascorbic (AA) and uric (UA) acids. Modified electrodes with self assembled layers (SAMs) show high selectivity, sensitivity, reproducibility and stability. A linear relationship between the epinephrine concentration and the current response is obtained in the range of 0.1 μM to 0.65 μM with the detection limit ≤0.065 μM for the electrodes modified at 2D surface and in the range of 0.1 μM to 0.75 μM with the detection limit ≤0.082 μM for the electrodes modified at the 3D surface.
Effect of urea on analyte complexation by 2,6‐dimethyl‐β‐CD in peptide enantioseparations by CE
Authors: Hammitzsch‐Wiedemann Manuela , Scriba Gerhard K. E.
Published: October 2009

The aim of the present study was the investigation of the effect of urea on analyte complexation in CD‐mediated separations of peptide enantiomers by CE in the pH range of about 2–5. pH‐independent complexation and mobility parameters in the absence and presence of 2 M urea were obtained by three‐dimensional, non‐linear curve fitting of the effective analyte mobility as a function of pH and heptakis‐(2,6‐di‐O‐methyl)‐β‐CD concentration. Urea led to decreased binding strength of the CD towards the protonated and neutral analyte enantiomers as well as to decreased mobilities of the free analytes. In contrast, mobilities of the fully protonated enantiomer–CD complexes as well as the pKa values of the free and complexed analytes increased. The effect of urea on separation efficiency varied with pH and CD concentration. In the case of Ala‐Tyr and Ala‐Phe, separations improved in the presence of urea at pH 2.2. In contrast, separations were impaired by urea at pH 3.8 and low concentrations of the CD. Decreased separation efficiency was noted for Asp‐PheOMe and Glu‐PheNH2 at low CD concentrations when urea was added but separations improved at higher CD concentrations over the entire pH range studied. The effect of urea on analyte complexation appeared to be primarily non‐stereoselective. Furthermore, the pH‐dependent reversal of the enantiomer migration order observed for Ala‐Tyr and Ala‐Phe can be rationalized by the complexation and mobility parameters.
Design of UEP‐Raptor codes over BEC
Authors: Yuan Lei. , An Jianping
Published: October 2009

In this paper, we propose a new scheme to construct Raptor codes that can provide unequal error protection (UEP) and unequal recovery time (URT) properties. We use joint optimisation of UEP‐LDPC codes and UEP‐LT codes to improve the performance of more important bits (MIB), and derive unequal density evolution (UDE) formulas over binary erasure channels (BEC). Using the UDE formulas, we optimise the UEP‐Raptor codes. For the finite length case, we compare our UEP‐Raptor codes with the previous UEP‐Raptor code. Simulation results show that, compared with the previous UEP‐Raptor code, the proposed UEP‐Raptor codes can get better performances of both MIB and less important bits (LIB). Copyright © 2009 John Wiley & Sons, Ltd.
Empirical analysis and forecasting of volatility dynamics in high‐frequency returns with time‐varying components
Authors: Man Kasing , Wu Chunchi
Published: October 2009

We study intraday return volatility dynamics using a time‐varying components approach, and the method is applied to analyze IBM intraday returns. Empirical evidence indicates that with three additive components—a time‐varying mean of absolute returns and two cosine components with time‐varying amplitudes—together they capture very well the pronounced periodicity and persistence behaviors exhibited in the empirical autocorrelation pattern of IBM returns. We find that the long‐run volatility persistence is driven predominantly by daily level shifts in mean absolute returns. After adjusting for these intradaily components, the filtered returns behave much like a Gaussian noise, suggesting that the three‐components structure is adequately specified. Furthermore, a new volatility measure (TCV) can be constructed from these components. Results from extensive out‐of‐sample rolling forecast experiments suggest that TCV fares well in predicting future volatility against alternative methods, including GARCH model, realized volatility and realized absolute value. Copyright © 2009 John Wiley & Sons, Ltd.
How sensitive is physician performance to alternative compensation schedules? Evidence from a large network of primary care clinics
Authors: Helmchen Lorens A. , Lo Sasso Anthony T.
Published: October 2009

Despite its centrality for the provision of health care, physician compensation remains understudied, and existing studies either fail to control for time trends, cover small samples from highly particular settings, or examine empirically negligible changes in reward levels. Using a four‐year sample of 59 physicians and 1.1 million encounters, we study how physicians at a network of primary care clinics responded when their salaried compensation plan was replaced with a lower salary plus substantial piece rates for encounters and select procedures. Although patient characteristics remained unchanged, physicians increased encounters by 11 to 61%, both by increasing encounters per day and days worked at the network, and increased procedures to the maximum reimbursable level. Copyright © 2009 John Wiley & Sons, Ltd.
The possible macroeconomic impact on the UK of an influenza pandemic
Authors: Keogh‐Brown Marcus R. , Wren‐Lewis Simon , Edmunds W. John , Beutels Philippe , Smith Richard D.
Published: October 2009

Little is known about the possible impact of an influenza pandemic on a nation's economy. We applied the UK macroeconomic model ‘COMPACT’ to epidemiological data on previous UK influenza pandemics, and extrapolated a sensitivity analysis to cover more extreme disease scenarios. Analysis suggests that the economic impact of a repeat of the 1957 or 1968 pandemics, allowing for school closures, would be short‐lived, constituting a loss of 3.35 and 0.58% of GDP in the first pandemic quarter and year, respectively. A more severe scenario (with more than 1% of the population dying) could yield impacts of 21 and 4.5%, respectively. The economic shockwave would be gravest when absenteeism (through school closures) increases beyond a few weeks, creating policy repercussions for influenza pandemic planning as the most severe economic impact is due to policies to contain the pandemic rather than the pandemic itself.

Accounting for changes in consumption patterns made in an attempt to avoid infection worsens the potential impact. Our mild disease scenario then shows first quarter/first year reductions in GDP of 9.5/2.5%, compared with our severe scenario reductions of 29.5/6%. These results clearly indicate the significance of behavioural change over disease parameters. Copyright © 2009 John Wiley & Sons, Ltd.
Disruption of ripple‐associated hippocampal activity during rest impairs spatial learning in the rat
Authors: Ego‐Stengel Valérie , Wilson Matthew A.
Published: October 2009

The hippocampus plays a key role in the acquisition of new memories for places and events. Evidence suggests that the consolidation of these memories is enhanced during sleep. At the neuronal level, reactivation of awake experience in the hippocampus during sharp‐wave ripple events, characteristic of slow‐wave sleep, has been proposed as a neural mechanism for sleep‐dependent memory consolidation. However, a causal relation between sleep reactivation and memory consolidation has not been established. Here we show that disrupting neuronal activity during ripple events impairs spatial learning. We trained rats daily in two identical spatial navigation tasks followed each by a 1‐hour rest period. After one of the tasks, stimulation of hippocampal afferents selectively disrupted neuronal activity associated with ripple events without changing the sleep‐wake structure. Rats learned the control task significantly faster than the task followed by rest stimulation, indicating that interfering with hippocampal processing during sleep led to decreased learning. © 2009 Wiley‐Liss, Inc.