bluuebunny/crossref_metadata_2025 huggingface dataset:
AcuteO-GlcNAcylation prevents inflammation-induced vascular dysfunction
Authors: Hilgers Rob H. P. , Xing Dongqi , Gong Kaizheng , Chen Yiu-Fai , Chatham John C. , Oparil Suzanne
Published: July 2012

Acute increases in cellular protein O-linked N-acetyl-glucosamine ( O-GlcNAc) modification ( O-GlcNAcylation) have been shown to have protective effects in the heart and vasculature. We hypothesized that d-glucosamine (d-GlcN) and Thiamet-G, two agents that increase protein O-GlcNAcylation via different mechanisms, inhibit TNF-α-induced oxidative stress and vascular dysfunction by suppressing inducible nitric oxide (NO) synthase (iNOS) expression. Rat aortic rings were incubated for 3h at 37°C with d-GlcN or its osmotic control l-glucose (l-Glc) or with Thiamet-G or its vehicle control (H2O) followed by the addition of TNF-α or vehicle (H2O) for 21 h. After incubation, rings were mounted in a myograph to assess arterial reactivity. Twenty-four hours of incubation of aortic rings with TNF-α resulted in 1) a hypocontractility to 60 mM K+solution and phenylephrine, 2) blunted endothelium-dependent relaxation responses to ACh and substance P, and 3) unaltered relaxing response to the Ca2+ionophore A-23187 and the NO donor sodium nitroprusside compared with aortic rings cultured in the absence of TNF-α. d-GlcN and Thiamet-G pretreatment suppressed the TNF-α-induced hypocontractility and endothelial dysfunction. Total protein O-GlcNAc levels were significantly higher in aortic segments treated with d-GlcN or Thiamet-G compared with controls. Expression of iNOS protein was increased in TNF-α-treated rings, and this was attenuated by pretreatment with either d-GlcN or Thiamet-G. Dense immunostaining for nitrotyrosylated proteins was detected in the endothelium and media of the aortic wall, suggesting enhanced peroxynitrite production by iNOS. These findings demonstrate that acute increases in protein O-GlcNAcylation prevent TNF-α-induced vascular dysfunction, at least in part, via suppression of iNOS expression.
Power Law Analysis of Financial Index Dynamics
Authors: Tenreiro Machado J. , Duarte Fernando B. , Duarte Gonçalo Monteiro
Published: July 2012

Power law (PL) and fractional calculus are two faces of phenomena with long memory behavior. This paper applies PL description to analyze different periods of the business cycle. With such purpose the evolution of ten important stock market indices (DAX, Dow Jones, NASDAQ, Nikkei, NYSE, S&P500, SSEC, HSI, TWII, and BSE) over time is studied. An evolutionary algorithm is used for the fitting of the PL parameters. It is observed that the PL curve fitting constitutes a good tool for revealing the signal main characteristics leading to the emergence of the global financial dynamic evolution.
Vive la Différence? Comparing “Like with Like” in Studies of Learners’ Ideas in Diverse Educational Contexts
Authors: Taber Keith S.
Published: July 2012

This paper considers the status of educational research that looks to replicate previous findings in a novel educational context, taking as its focus an active area of research in a range of national contexts: studies into students’ ideas about scientific topics. The paper considers the circumstances under which a “replication” study should be considered to offer original new knowledge worthy of publication in international research journals. It is argued here that there are sound principled reasons to expect studies undertaken in different educational contexts to be able to contribute to a progressive research programme, and so researchers should be encouraged to undertake such work. However, technically competent papers submitted to prestigious journals will be rejected if they are considered to merely replicate previous work without offering novel empirical or theoretical content that is considered to make an original contribution. This paper explores the basis for welcoming research “testing-out” published findings in new contexts and considers the place of such studies within a progressive research programme. This analysis can inform research design for those looking to explore learners’ ideas in local educational contexts, by offering clear guidance on the forms of research likely to offer significant contributions to public knowledge.
Unconstraining Methods in Revenue Management Systems: Research Overview and Prospects
Authors: Guo Peng , Xiao Baichun , Li Jun
Published: July 2012

Demand unconstrainingis one of the key techniques to the success of revenue management systems. This paper surveys the history of research on unconstraining methods and reviews over 130 references including the latest research works in the area. We discuss the relationship betweencensoreddata unconstraining and forecasting and review five alternative unconstraining approaches. These methods consider data unconstraining in various situations such as single-class, multi-class, and multi-flight. The paper also proposes some future research questions to bridge the gap between theory and applications.
A Novel Programmable CMOS Fuzzifiers Using Voltage-to-Current Converter Circuit
Authors: Abdulla K. P. , Fazle Azeem Mohammad
Published: July 2012

This paper presents a new voltage-input, current-output programmable membership function generator circuit (MFC) using CMOS technology. It employs a voltage-to-current converter to provide the required current bias for the membership function circuit. The proposed MFC has several advantageous features. This MFC can be reconfigured to perform triangular, trapezoidal, S-shape, Z-Shape, and Gaussian membership forms. This membership function can be programmed in terms of its width, slope, and its center locations in its universe of discourses. The easily adjustable characteristics of the proposed circuit and its accuracy make it suitable for embedded system and industrial control applications. The proposed MFC is designed using the spice software, and simulation results are obtained.
Vascularisation Pattern of Chronic Pancreatitis Compared with Pancreatic Carcinoma: Results from Contrast-Enhanced Endoscopic Ultrasound
Authors: Hocke Michael , Dietrich Christoph F.
Published: July 2012

Discriminating between focal chronic pancreatitis and pancreatic cancer is always a challenge in clinical medicine. Contrast-enhanced endoscopic ultrasound using Doppler techniques can uniquely reveal different vascularisation patterns in pancreatic tissue alterated by chronic inflammatory processes and even allows a discrimination from pancreatic cancer. This paper will describe the basics of contrast-enhanced high mechanical index endoscopic ultrasound (CEHMI EUS) and contrast enhanced low mechanical index endoscopic ultrasound (CELMI EUS) and explain the pathophysiological differences of the vascularisation of chronic pancreatitis and pancreatic carcinoma. Furthermore it will discuss how to use these techniques in daily clinical practice.
Duplex Ultrasound Evaluation of Hemodialysis Access: A Detailed Protocol
Authors: Teodorescu Victoria , Gustavson Susan , Schanzer Harry
Published: July 2012

A detailed protocol for the performance and interpretation of duplex ultrasound evaluation of hemodialysis access is described.
A New Efficient Method for Nonlinear Fisher‐Type Equations
Authors: Aminikhah Hossein , Mehrdoust Farshid , Jamalian Ali
Published: July 2012

Laplace transform and new homotopy perturbation methods are adopted to study Fisher‐type equations analytically. The solutions introduced in this study can be used to obtain the closed form of the solutions if they are required. The combined method needs less work in comparison with the other homotopy perturbation methods and decreases volume of calculations considerably. The method is tested on various examples, and results show that new method is more effective and convenient to use, and high accuracy of it is evident.
FTIR and Raman Spectral Research on Metamorphism and Deformation of Coal
Authors: Li Xiaoshi , Ju Yiwen , Hou Quanlin , Li Zhuo , Fan Junjia
Published: July 2012

Under different metamorphic environments, coal will form different types of tectonically deformed coal (TDC) by tectonic stress and even the macromolecular structure can be changed. The structure and composition evolution of TDC have been investigated in details using Fourier transform infrared spectroscopy and Raman spectroscopy. The ductile deformation can generate strain energy via increase of dislocation in molecular structure of TDC, and it can exert an obvious influence on degradation and polycondensation. The brittle deformation can generate frictional heat energy and promote the metamorphism and degradation, but less effect on polycondensation. Furthermore, degradation affects the structural evolution of coal in lower metamorphic stage primarily, whereas polycondensation is the most important controlling factor in higher metamorphic stage. Tectonic deformation can produce secondary structural defects in macromolecular structure of TDC. Under the control of metamorphism and deformation, the small molecules which break and fall off from the macromolecular structure of TDC are replenished and embedded into the secondary structural defects preferentially and form aromatic rings by polycondensation. These processes improved the stability of macromolecular structure greatly. It is easier for ductile deformation to induce secondary structural defects than in brittle deformation.
Acute Pancreatitis Secondary to Gestational Hypertriglyceridaemia
Authors: Cahalane Alexis M. , Smith Myles J. , Ryan James , Maguire Donal
Published: July 2012

Gestational hypertriglyceridaemia is a rare cause of acute pancreatitis. Its pathophysiology is incompletely understood. Severity scoring and effective management remain challenging. We report a case of acute pancreatitis secondary to gestational hypertriglyceridaemia. We describe the use of computed tomography to provide an alternative determination of severity, as well as plasmapheresis as a means of treating the condition.
Impact of the NK Cell Receptor LIR-1 (ILT-2/CD85j/LILRB1) on Cytotoxicity against Multiple Myeloma
Authors: Heidenreich Silke , zu Eulenburg Christine , Hildebrandt York , Stübig Thomas , Sierich Heidi , Badbaran Anita , Eiermann Thomas H. , Binder Thomas M. C. , Kröger Nicolaus
Published: July 2012

The role of different receptors in natural-killer- (NK-) cell-mediated cytotoxicity against multiple myeloma (MM) cells is unknown. We investigated if an enhancement of NK-cell-mediated cytotoxicity against MM could be reached by blocking of the inhibitory leukocyte immunoglobulin-like receptor 1 (LIR-1). Our investigations revealed high levels of LIR-1 expression not only on the NK cell line NK-92, but also on myeloma cells (MOLP-8, RPMI8226) as well as on a lymphoblastoid cell line (LBCL; IM-9). Subsequent cytotoxicity assays were designed to show the isolated effects of LIR-1 blocking on either the effector or the tumor side to rule out receptor-receptor interactions. Although NK-92 was shown to be capable of myeloma cell lysis, inhibition of LIR-1 on NK-92 did not enhance cytotoxicity. Targeting the receptor on MM and LBCL did not also alter NK-92-mediated lysis. We come to the conclusion that LIR-1 alone does not directly influence NK-cell-mediated cytotoxicity against myeloma. To our knowledge, this work provides the first investigation of the inhibitory capability of LIR-1 in NK-92-mediated cytotoxicity against MM and the first functional evaluation of LIR-1 on MM and LBCL.
Cutaneous Inflammatory Malignant Fibrous Histiocytoma Presenting with a Leukemoid Reaction: A Case Report and Review of the Literature
Authors: Hurtado-Cordovi Jorge , Avezbakiyev Boris , Frieri Marianne , Freedman Lester , Gebre Wondwoosen
Published: July 2012

Malignant fibrous histiocytoma (MFH) is the most common sarcoma found in adults. We discuss a case of inflammatory MFH of dermal/epidermal origin presenting with a severe leukemoid reaction (LR). A 60 years old white male presented to hematology/oncology clinic complaining of mild shortness of breath on exertion. Past medical history was remarkable for removal of a left upper extremity necrotic mass 4.4 × 3 × 3 cm. Microscopy of the specimen showed clear surgical margin, and tumor cells restricted to the dermis without lymphovascular invasion. Immunohistochemestry was positive for CD 68 and CD 99. Chest x-ray was negative for metastatic disease. White blood cell count was 109.4 k/mm3with 24 k/mm3band neutrophils, and absolute neutrophil count of 69 k/mm3. CT scan of the thorax revealed numerous bilateral pulmonary nodules suspicious for metastasis. Based on these findings patient was diagnosed with metastatic cutaneous IMFH associated with a LR. Following review of medical literature, this appears to be the first reported case of inflammatory cutaneous MFH associated with LR. This histological variant is rare, and carries a poor prognosis. Thus, we would like to emphasize the need for investigating alternative therapies capable of improving the survival of these patients.
Green Tea Polyphenols for the Protection against Renal Damage Caused by Oxidative Stress
Authors: Yokozawa Takako , Noh Jeong Sook , Park Chan Hum
Published: July 2012

Green tea, prepared from the leaves ofCamellia sinensisL., is a beverage that is popular worldwide. Polyphenols in green tea have been receiving much attention as potential compounds for the maintenance of human health due to their varied biological activity and low toxicity. In particular, the contribution of antioxidant activity to the prevention of diseases caused by oxidative stress has been focused upon. Therefore, in this study, we investigated the effects of (−)-epigallocatechin 3-O-gallate and (−)-epigallocatechin 3-O-gallate, which account for a large fraction of the components of green tea polyphenol, on oxidative stress-related renal disease. Our observations suggest that green tea polyphenols have a beneficial effect on pathological states related to oxidative stress of the kidney.
Ultrasound Determination of Gestational Age Using Placental Thickness in Female Dogs: An Experimental Study
Authors: Maldonado André Luiz Louzada , Araujo Júnior Edward , Mendonça Débora Sartori , Nardozza Luciano Marcondes Machado , Moron Antonio Fernandes , Ajzen Sérgio Aron
Published: July 2012

Objective. To verify if the placental thickness allows determining the gestational age, evaluating the correlation between the referred gestational age with the studied one, and the accuracy of the placental thickness measurement (biometry) with fetal morphologic parameters in bitches.Methods. The placental thickness of 336 bitches of diverse breeds was evaluated. Bitches were divided in three groups by body weight: small, medium, and big large size. The gestations pregnancies were evaluated by ultrasound from the third week of gestation. An analysis was performed between the mean values of the gestational age obtained of placental thickness by adjustment of curves and the reported gestational age. Student'st-test was applied to compare the mean of reported and placental thickness gestational age. Significance was defined asP<0.05.Results. A positive and statistically significant correlation exists between the placental thickness and gestational age. The expression that presents the best correlation coefficient and explanation was thickness of placenta = 0.021xgestational age −0.314.Conclusion. It is possible to determine the gestational age in relation to the placental thickness measured by ultrasound in bitches with a satisfactory accuracy in relation to fetal morphologic parameters as gestational vesicle, ribs, or kidneys.
Biomarker Discovery of Pancreatic and Gastrointestinal Cancer by 2DICAL: 2-Dimensional Image-Converted Analysis of Liquid Chromatography and Mass Spectrometry
Authors: Ono Masaya , Kamita Masahiro , Murakoshi Yusuke , Matsubara Junichi , Honda Kazufumi , Miho Banno , Sakuma Tomohiro , Yamada Tesshi
Published: July 2012

Biomarkers tested by blood sample are of great use to clinicians as they provide useful information to aid an early and accurate diagnosis. Comprehensive “omics” studies are expected to facilitate the identification of such new biomarkers, and much research is being performed in this area. Our proteomics analysis system of 2-dimensional image-converted analysis of liquid chromatography and mass spectrometry (2DICAL) has successfully identified several new blood biomarkers from the clinical blood samples of pancreatic and colorectal cancer patients.
Chover‐Type Laws of the Iterated Logarithm for Continuous Time Random Walks
Authors: Hwang Kyo-Shin , Wang Wensheng
Published: July 2012

A continuous time random walk is a random walk subordinated to a renewal process used in physics to model anomalous diffusion. In this paper, we establish Chover‐type laws of the iterated logarithm for continuous time random walks with jumps and waiting times in the domains of attraction of stable laws.
Amyloid Oligomers Exacerbate Tau Pathology in a Mouse Model of Tauopathy
Authors: Selenica Maj-Linda B. , Brownlow Milene , Jimenez Jeffy P. , Lee Daniel C. , Pena Gabriela , Dickey Chad A. , Gordon Marcia N. , Morgan Dave
Published: July 2012

Background: We aimed to investigate the influence of oligomeric forms of β-amyloid (Aβ) and the influence of the duration of exposure on the development of tau phosphorylation. Methods: Aβ oligomers were injected intracranially either acutely into 5-month-old rTg4510 mice and tissue was collected 3 days later, or chronically into 3-month-old mice and tissue was collected 2 months later. Several forms of phosphorylated tau (p-tau), GSK3 (glycogen synthase kinase-3) and microglial and astrocyte activation were measured. Results: Acute injections of Aβ oligomers had no effect on p-tau epitopes but did result in elevation of phosphorylated/activated GSK3 (pGSK3). Chronic infusion of Aβ oligomers into the right hippocampus resulted in 3- to 4-fold elevations in several p-tau isoforms with no changes in total tau levels. A significant elevation in pGSK3 accompanied these changes. Microglial staining with CD68 paralleled the increase in tau phosphorylation, however, CD45 staining was unaffected by Aβ. Control experiments revealed that the infusion of Aβ from the minipumps was largely complete by 10 days after implantation. Thus, the elevation in p-tau 2 months after implantation implies that the changes are quite persistent. Conclusion: Soluble Aβ1-42 oligomers have long-lasting effects on tau phosphorylation in the rTg4510 model, possibly due to elevations in GSK3. These data suggest that even brief elevations in Aβ production, may have enduring impact on the risk for tauopathy.
An Asthma Action Plan Created by Physician, Educator and Patient Online Collaboration with Usability and Visual Design Optimization
Authors: Gupta Samir , Wan Flora T. , Hall Susan E. , Straus Sharon E.
Published: July 2012

Background: Asthma action plans (AAPs), which decrease hospitalizations and improve symptom control, are recommended in guidelines, but are seldom delivered to patients. Existing AAPs have been developed by experts, without the inclusion of all stakeholders (such as patients with asthma) and without specifically addressing usability and visual design. Objective: Our objective was to develop a more usable AAP by involving all stakeholders and considering design preferences. Methods: We created a Wiki-based system for multiuser AAP development. Pulmonologists, primary care physicians, asthma educators and patients used the system to collaboratively compile a single AAP by making multiple online selections over 1 week. We combined common elements from 3 AAPs developed in this way into 1, optimized visual design features and tested face validity in focus groups. Results: A total of 41 participants averaged 646 selections/week over a login-time of 28.8 h/week. Of 35 participants, 28 (80%) were satisfied with the final AAP and 32 (91%) perceived that they would be able to use it. The plans created by the 3 groups were very similar, with a unanimous or majority agreement in the handling of 100/110 (91%) AAP options. Conclusions: Inclusion of multiple stakeholders and focus on design preferences predict enhanced usability and uptake of medical tools. The validity of our AAP is further supported by the similarity between the AAPs created by each group, user engagement and satisfaction with the plan and agreement with existing validity criteria proposed by experts. This AAP can be implemented in care with a concurrent measurement of uptake and health impact.
A Novel Locus for Restless Legs Syndrome on Chromosome 13q
Authors: Balaban Hatice , Bayrakli Fatih , Kartal Ugur , Pinarbasi Ergun , Topaktas Suat , Kars Hamit Zafer
Published: July 2012

Background: Restless legs syndrome (RLS) is a sensorimotor disorder in which affected individuals suffer from uncomfortable sensations and an urge to move their lower limbs; it occurs mainly in resting situations during the evening or at night. Multiple chromosomal loci have been mapped for RLS through family-based linkage analysis, and genome-wide association studies but causative mutations have not been identified yet. Method: We identified an RLS family from the eastern part of central Turkey which has 10 patients suffering from this syndrome. Whole genome linkage analysis was performed in family members who consented for study (9 affected and 2 unaffected). Results: A theoretical maximum logarithm of the odds score of 3.29 was identified at chromosome 13q32.3–33.2. This result shows strong genetic linkage to this locus. Conclusions: We demonstrated a genetic linkage at chromosome 13 in a RLS family. Further investigation in this linkage area may reveal a causative gene leading to RLS phenotype and may illuminate the pathogenesis of this disease. This study supports the genetic heterogeneity in the pathogenesis of this syndrome.
Spirometric Reference Values for Advanced Age from a South German Population
Authors: Karrasch Stefan , Flexeder Claudia , Behr Jürgen , Holle Rolf , Huber Rudolf M. , Jörres Rudolf A. , Nowak Dennis , Peters Annette , Wichmann H.-Erich , Heinrich Joachim , Schulz Holger ,   for the KORA Study Group
Published: July 2012

Background: The diagnostic use of lung function using spirometry depends on the validity of reference equations. A multitude of spirometric prediction values have been published, but in most of these studies older age groups are underrepresented. Objectives: The aim of the present study was to establish new spirometric reference values for advanced age and to compare these to recent prediction equations from population-based studies. Methods: In the present study spirometry was performed in a population-based sample from the KORA-F4 and KORA-Age cohorts (2006-2009, Augsburg, Germany) comprising 592 never-smoking subjects aged 42-89 years and with no history of respiratory disease. Using quantile regression analysis, equations for the median and lower limit of normal were derived for indices characterizing the expiratory flow-volume curve: forced expiratory volume in 1 s (FEV1), forced vital capacity (FVC), FEV1/FVC, peak expiratory flow (PEF), and forced expiratory flow rates at 25, 50 and 75% of exhaled FVC (FEF25, FEF50 and FEF75). Results: FEV1 and FVC were slightly higher, and PEF was lower compared to recently published equations. Importantly, forced expiratory flow rates at middle and low lung volume, as putative indicators of small airway disease, were in good agreement with recent data, especially for older age. Conclusion: Our study provides up-to-date reference equations for all major indices of flow-volume curves in middle and advanced age in a South German population. The small deviations from published equations indicate that there might be some regional differences of lung function within the Caucasian population of advanced age in Europe.
Comparison of Epidermal Growth Factor Receptor Mutation Statuses in Tissue and Plasma in Stage I–IV Non-Small Cell Lung Cancer Patients
Authors: Zhao Xiao , Han Ru-Bing , Zhao Jing , Wang Jun , Yang Fan , Zhong Wei , Zhang Li , Li Long-Yun , Wang Meng-Zhao
Published: July 2012

Background: Epidermal growth factor receptor (EGFR) mutations play essential roles in the treatment of non-small cell lung cancer (NSCLC) patients using EGFR tyrosine kinase inhibitors. Detection of EGFR mutations in blood cell-free DNA (cfDNA) seems promising. However, the mutation status in the plasma/serum is not always consistent with that in the tissues. Objectives: The aims of this study were to compare the mutation statuses in plasma to those in tissues and thus to determine the specific subgroups of NSCLC patients who may be the best candidates for EGFR mutation analyses using blood cfDNA. Methods: A total of 111 pairs of tissue and plasma samples were collected. Mutant-enriched PCR and sequencing analyses were performed to detect EGFR exon 19 deletions and exon 21 L858R mutations. Results: Mutations were discovered in 43.2% (48/111) of the patients. The overall rate of consistency of the EGFR mutation statuses for the 111 paired plasma and tissue samples was 71.2% (79/111). The sensitivity and specificity rates of detecting EGFR mutations in the plasma were 35.6% (16/45) and 95.5% (63/66), respectively. The disease stage and tumor differentiation subgroups showed significantly different detection sensitivities; the sensitivity was 10% in early-stage patients and 56% in advanced-stage patients (p = 0.0014). For patients with poorly differentiated tumors, the sensitivity was 77.8%, which was significantly different from those with highly differentiated (20%; p = 0.0230) and moderately differentiated tumors (19%; p = 0.0042). Conclusion: Blood analyses for EGFR mutations may be effectively used in advanced-stage patients or patients with poorly differentiated tumors.
Volume Is Not the Only Key to Hypertension Control in Dialysis Patients
Authors: Odudu Aghogho , McIntyre Christopher
Published: July 2012

There is a widely held belief that hypervolaemia due to excess intake or inadequate removal of salt and water is the principal cause of hypertension in dialysis patients. The risk of failing to consider additional pathophysiological elements is that inadequate or inappropriate therapeutic strategies may be adopted. This review aims to highlight multiple alternative mechanisms for hypertension in this setting along with the risks of probing for normotension by empirical dry weight reduction if dry weight is imprecisely defined.
Leak during Manual Neonatal Ventilation and Its Effect on the Delivered Pressures and Volumes: An in vitro Study
Authors: Hartung J.C. , te Pas A.B. , Fischer H. , Schmalisch G. , Roehr C.C.
Published: July 2012

Background: Mask leak is a frequent problem during manual ventilation. Our aim was to investigate the effect of predefined leaks on delivered peak inflation pressure (PIP), positive end-expiratory pressure (PEEP) and tidal volume (Vt) when using different neonatal manual ventilation devices. Methods: A neonatal-lung model was ventilated at different respiratory rates (RRs, 40, 60, 80/min) using a mechanically operated self-inflating bag (SIB) and a manually operated T-piece resuscitator (PIP = 20 cm H2O, PEEP = 5 cm H2O). Four open tubes of different lengths, which produced up to 90% leak, were consecutively attached between the ventilation device and the lung model. A pneumotachograph was used to measure pressures, flow and volume. Results: With increasing leak (0–90%) PIP and PEEP decreased significantly (p < 0.001) for both devices. Using the SIB, the mean ± SD PIP fell from 20.1 ± 0.3 to 15.9 ± 7 cm H2O and PEEP fell from 5.0 ± 0 to 0.3 ± 0.5 cm H2O, leading to an increased pressure difference (Δp); Vt increased from 8.8 ± 0.7 to 11.1 ± 0.8 ml (p < 0.001). With increasing RRs, the leak-dependent changes were significantly lower (p < 0.001). Using the T-piece resuscitator, PIP dropped independent of RRs from 20.3 ± 0.5 to 18.5 ± 0.6 cm H2O and PEEP from 5.1 ± 0.4 to 4.0 ± 0 cm H2O, while Δp and Vt did not differ significantly. Conclusion: The decrease in PIP and PEEP with increasing leak is RR dependent and distinctly higher when using an SIB compared to a T-piece device. In contrast to Vt delivered with the SIB, Vt delivered by the T-piece resuscitator was nearly constant even for leaks up to 90%.
Endometrioma ≤3 cm in Diameter per se Does Not Affect Ovarian Reserve in Intracytoplasmic Sperm Injection Cycles
Authors: Esinler Ibrahim , Bozdag Gurkan , Arikan Ilker , Demir Bulent , Yarali Hakan
Published: July 2012

Background: Our aim was to determine the effect of single endometriomas ≤3 cm in diameter per se on ovarian reserve in intracytoplasmic sperm injection (ICSI) cycles. Methods: We enrolled 19 consecutive infertile patients (29 cycles) who had unilateral single endometriomas ≤3 cm in diameter and who underwent ICSI. Results: The mean age of the patients was 33.3 ± 4.9 years. The mean diameter of endometriomas was 21.8 ± 4.9 mm. Left- and right-sided endometriomas were 34.5 and 65.5%, respectively. The number of oocytes retrieved from ovaries with endometriomas and contralateral normal ovaries was comparable (5.9 ± 4.3 vs. 5.4 ± 3.8). Conclusion: Endometriomas ≤3 cm in diameter per se did not have a deleterious effect on ovarian reserve in ICSI cycles.
S-Nitrosation of β-Catenin and p120 Catenin
Authors: Marín Natalie , Zamorano Patricia , Carrasco Rodrigo , Mujica Patricio , González Francisco G. , Quezada Claudia , Meininger Cynthia J. , Boric Mauricio P. , Durán Walter N. , Sánchez Fabiola A.
Published: July 2012

Rationale:

Endothelial adherens junction proteins constitute an important element in the control of microvascular permeability. Platelet-activating factor (PAF) increases permeability to macromolecules via translocation of endothelial nitric oxide synthase (eNOS) to cytosol and stimulation of eNOS-derived nitric oxide signaling cascade. The mechanisms by which nitric oxide signaling regulates permeability at adherens junctions are still incompletely understood.

Objective:

We explored the hypothesis that PAF stimulates hyperpermeability via S-nitrosation (SNO) of adherens junction proteins.

Methods and Results:

We measured PAF-stimulated SNO of β-catenin and p120-catenin (p120) in 3 cell lines: ECV-eNOSGFP, EAhy926 (derived from human umbilical vein), and postcapillary venular endothelial cells (derived from bovine heart endothelium) and in the mouse cremaster muscle in vivo. SNO correlated with diminished abundance of β-catenin and p120 at the adherens junction and with hyperpermeability. Tumor necrosis factor-α increased nitric oxide production and caused similar increase in SNO as PAF. To ascertain the importance of eNOS subcellular location in this process, we used ECV-304 cells transfected with cytosolic eNOS (GFPeNOSG2A) and plasma membrane eNOS (GFPeNOSCAAX). PAF induced SNO of β-catenin and p120 and significantly diminished association between these proteins in cells with cytosolic eNOS but not in cells wherein eNOS is anchored to the cell membrane. Inhibitors of nitric oxide production and of SNO blocked PAF-induced SNO and hyperpermeability, whereas inhibition of the cGMP pathway had no effect. Mass spectrometry analysis of purified p120 identified cysteine 579 as the main S-nitrosated residue in the region that putatively interacts with vascular endothelial-cadherin.

Conclusions:

Our results demonstrate that agonist-induced SNO contributes to junctional membrane protein changes that enhance endothelial permeability.
Elderly Blacks Have a Blunted Sympathetic Neural Responsiveness But Greater Pressor Response to Orthostasis Than Elderly Whites
Authors: Okada Yoshiyuki , Galbreath M. Melyn , Jarvis Sara S. , Bivens Tiffany B. , Vongpatanasin Wanpen , Levine Benjamin D. , Fu Qi
Published: July 2012

Neural control of blood pressure (BP) has been reported to differ between young blacks and whites. We hypothesized that elderly blacks have enhanced sympathetic neural responses during orthostasis compared with elderly whites. Muscle sympathetic nerve activity, arm-cuff BP, and heart rate were recorded continuously, and cardiac output, stroke volume, and total peripheral resistance were measured intermittently during supine and 5-minute 60° upright tilt in 10 blacks (65 [SD, 4] years; 4 women) and 20 whites (68 [6] years; 8 women). We found that muscle sympathetic nerve activity burst frequency was similar between blacks and whites in the supine position (44 [10] versus 42 [7] bursts per minute) and during upright tilt (59 [11] versus 60 [9] bursts per minute;
P
=0.846 for race,
P
<0.001 for posture, and
P
=0.622 for interaction). However, upright total muscle sympathetic nerve activity was smaller in blacks than in whites (162 [39] versus 243 [112]%;
P
=0.003). Systolic BP, heart rate, cardiac output, and stroke volume were not different between groups. Diastolic BP was similar in the supine position, increased in all of the subjects during tilting; upright diastolic BP was greater in blacks than in whites (80 [10] versus 71 [7] mmHg;
P
=0.008). Total peripheral resistance did not differ between blacks and whites in the supine position or during upright tilt (
P
=0.354 for race,
P
<0.001 for posture,
P
=0.825 for interaction). Thus, elderly blacks have a blunted sympathetic neural responsiveness but enhanced pressor response to orthostasis compared with elderly whites, which may be attributable to an augmented sympathetic vascular transduction and/or nonadrenergic vasoconstrictor mechanisms (ie, angiotensin II or the venoarteriolar response).
Chronic Hypoxia During Gestation Causes Epigenetic Repression of the Estrogen Receptor-α Gene in Ovine Uterine Arteries via Heightened Promoter Methylation
Authors: Dasgupta Chiranjib , Chen Man , Zhang Haitao , Yang Shumei , Zhang Lubo
Published: July 2012

Estrogen receptor-α (ERα) plays a key role in the adaptation of increased uterine blood flow in pregnancy. Chronic hypoxia is a common stress to maternal cardiovascular homeostasis and causes increased risk of preeclampsia. Studies in pregnant sheep demonstrated that hypoxia during gestation downregulated ERα gene expression in uterine arteries. The present study tested the hypothesis that hypoxia causes epigenetic repression of the ERα gene in uterine arteries via heightened promoter methylation. Ovine ERα promoter of 2035 bp spanning from −2000 to +35 of the transcription start site was cloned. No estrogen or hypoxia-inducible factor response elements were found at the promoter. Two transcription factor binding sites, USF
−15
and Sp1
−520
, containing CpG dinucleotides were identified, which had significant effects on the promoter activity. The USF element binds transcription factors USF1 and USF2, and the Sp1 element binds Sp1, as well as ERα through Sp1. Deletion of the Sp1 site abrogated 17β-estradiol–induced increase in the promoter activity. In normoxic control sheep, CpG methylation at the Sp1 but not the USF site was significantly decreased in uterine arteries of pregnant as compared with nonpregnant animals. In pregnant sheep exposed to long-term high-altitude hypoxia, CpG methylation at both Sp1 and USF sites in uterine arteries was significantly increased. Methylation inhibited transcription factor binding and the promoter activity. The results provide evidence of hypoxia causing heightened promoter methylation and resultant ERα gene repression in uterine arteries and suggest new insights of molecular mechanisms linking gestational hypoxia to aberrant uteroplacental circulation and increased risk of preeclampsia.
Murine Recombinant Angiotensin-Converting Enzyme 2
Authors: Ye Minghao , Wysocki Jan , Gonzalez-Pacheco Francisco R. , Salem Mahmoud , Evora Karla , Garcia-Halpin Laura , Poglitsch Marko , Schuster Manfred , Batlle Daniel
Published: July 2012

A newly produced murine recombinant angiotensin (Ang)-converting enzyme 2 (ACE2) was characterized in vivo and in vitro. The effects of available ACE2 inhibitors (MLN-4760 and 2 conformational variants of DX600, linear and cyclic) were also examined. When murine ACE2 was given to mice for 4 weeks, a marked increase in serum ACE2 activity was sustainable. In acute studies, mouse ACE2 (1 mg/kg) obliterated hypertension induced by Ang II infusion by rapidly decreasing plasma Ang II. These effects were blocked by MLN-4760 but not by either form of DX600. In vitro, conversion from Ang II to Ang-(1-7) by mouse ACE2 was blocked by MLN-4760 (10
−6
m
) but not by either form of DX600 (10
−5
m
). Quantitative analysis of multiple Ang peptides in plasma ex vivo revealed formation of Ang-(1-9) from Ang I by human but not by mouse ACE2. Both human and mouse ACE2 led to the dissipation of Ang II with formation of Ang (1-7). By contrast, mouse ACE2-driven Ang-(1-7) formation from Ang II was blocked by MLN-4760 but not by either linear or cyclic DX600. In conclusion, sustained elevations in serum ACE2 activity can be accomplished with murine ACE2 administration, thereby providing a strategy for ACE2 amplification in chronic studies using rodent models of hypertension and cardiovascular disease. Human but not mouse ACE2 degrades Ang I to form Ang-(1-9). There are also species differences regarding rodent and human ACE2 inhibition by known inhibitors such that MLN-4760 inhibits both human and mouse ACE2, whereas DX600 only blocks human ACE2 activity.
Normal IgG Downregulates the Intracellular Superoxide Level and Attenuates Migration and Permeability in Human Aortic Endothelial Cells Isolated From a Hypertensive Patient
Authors: Wang Xiuqing , Wang Qianyu , Sun Zhongjie
Published: July 2012

The normal IgG, a circulating antibody, is maintained at a constant level in humans. However, little is known regarding whether normal IgG has effects on the function of vascular endothelial cells. The purpose of this study was to investigate whether IgG affects superoxide (O
2
·−
) generation and cell permeability in human aortic endothelial cells (HAECs) isolated from a hypertensive patient. The effect of normal human IgG on endothelial cell function was investigated in cultured HAECs isolated from a hypertensive patient who died of stroke. The results demonstrated, for the first time, that normal IgG attenuated the intracellular O
2
·−
level and decreased cell migration, cell permeability, and stress fiber formation in HAECs. IgG significantly decreased Rac1 activity and NADPH oxidase activity but upregulated Mn superoxide dismutase expression in HAECs, which may contribute to the IgG-induced decrease in O
2
·−
level. It is noted that AMP-activated protein kinase (AMPK) was activated by IgG, as evidenced by increased phosphorylation of AMPK. Interestingly, inhibition of AMPK by an AMPK inhibitor abolished IgG-induced decreases in Rac1 and NADPH oxidase activities and IgG-induced increases in Mn superoxide dismutase expression, suggesting that AMPK is an important mediator of the IgG-induced regulation of these enzymes. Importantly, inhibition of AMPK activity also prevented the IgG-induced decrease in O
2
·−
levels, cell migration, cell permeability, and stress fiber formation. Therefore, normal human IgG may protect HAECs via activation of AMPK and subsequent decreases in intracellular O
2
·−
. These findings reveal a previously unidentified role of normal IgG in regulating AMPK and endothelial cell function.
Deciphering the Parts List for the Mechanical Plant
Authors: Somerville Chris
Published: July 2012

The development of inexpensive DNA sequencing technologies has revolutionized all aspects of biological research. The proliferation of plant genome sequences, in conjunction with the parallel development of robust tools for directed genetic manipulation, has given momentum and credibility to the goal of understanding several model plants as the sum of their parts. A broad inventory of the functions and interrelationships of the parts is currently under way, and the first steps toward computer models of processes have emerged. These approaches also provide a framework for the mechanistic basis of plant diversity. It is hoped that rapid progress in this endeavor will facilitate timely responses to expanding demand for food, feed, fiber, fuel, and ecosystem services in a period of climate change.
Restarted Local Search Algorithms for Continuous Black Box Optimization
Authors: Pošík Petr , Huyer Waltraud
Published: July 2012

Several local search algorithms for real-valued domains (axis parallel line search, Nelder-Mead simplex search, Rosenbrock's algorithm, quasi-Newton method, NEWUOA, and VXQR) are described and thoroughly compared in this article, embedding them in a multi-start method. Their comparison aims (1) to help the researchers from the evolutionary community to choose the right opponent for their algorithm (to choose an opponent that would constitute a hard-to-beat baseline algorithm), (2) to describe individual features of these algorithms and show how they influence the algorithm on different problems, and (3) to provide inspiration for the hybridization of evolutionary algorithms with these local optimizers. The recently proposed Comparing Continuous Optimizers (COCO) methodology was adopted as the basis for the comparison. The results show that in low dimensional spaces, the old method of Nelder and Mead is still the most successful among those compared, while in spaces of higher dimensions, it is better to choose an algorithm based on quadratic modeling, such as NEWUOA or a quasi-Newton method.
The Performance of Hydrological Monthly Products Using SSM/I–SSMI/S Sensors
Authors: Vila Daniel , Hernandez Cecilia , Ferraro Ralph , Semunegus Hilawe
Published: July 2012

Global monthly rainfall estimates and other hydrological products have been produced from 1987 to the present using measurements from the Defense Meteorological Satellite Program (DMSP) series of the Special Sensor Microwave Imager (SSM/I). The aim of this paper is twofold: to present the recent efforts to improve the quality control (QC) of historical antenna temperature of the SSM/I sensor (1987–2008) and how this improvement impacts the different hydrological products that are generated at NOAA/National Environmental Satellite, Data, and Information Service (NESDIS). Beginning in 2005, the DMSP Special Sensor Microwave Imager/Sounder (SSMI/S) has been successfully operating on the F-16, F-17, and F-18 satellites. The second objective of this paper is focused on the application of SSMI/S channels to evaluate the performance of several hydrological products using the heritage of existing SSM/I algorithms and to develop an improved strategy to extend the SSM/I time series into the SSMI/S era, starting with data in 2009 for F-17. The continuity of hydrological products from SSM/I to SSMI/S has shown to be a valuable contribution for the precipitation and climate monitoring community but several sensor issues must be accounted for to meet this objective.
Least Squares Reconstruction of Doppler Radar Spectra for Irregular PRT
Authors: Kalogiros John
Published: July 2012

A least squares method for the reconstruction of Doppler spectra of weather radars with irregular pulse repetition time used to increase the range of unambiguous velocity is presented and evaluated. This method is a robust spectral method that is based on the least squares minimum norm principle and reconstructs both the magnitude and the phase of the discrete Fourier transform of the signal. The phase spectrum is useful in the estimation of the differential phase in dual-polarization radars with staggered sampling schemes, which is a case of irregular sampling. A computationally efficient iterative algorithm for estimating the mean frequency of the signal, which is required for the reconstruction of the spectrum, is described for possible real-time applications. A clutter filter method based on spectral interpolation, which can be applied to echoes with generally nonzero mean velocity, is also described and combined with the spectrum reconstruction method. Using simulated data it is shown that the least squares reconstruction method with or without the presence of clutter gives results with small bias and standard error and can be applied to wide spectra. The application of the method to real X-band radar data with a low signal-to-noise ratio and a high stagger ratio value of ⅚ showed that the least squares method has low sensitivity to the stagger ratio and satisfactorily gives spectral reconstruction for signal-to-noise ratio values as low as 10 dB.
Space–Time Scales of Northward Propagation of Convection during Boreal Summer
Authors: Chakraborty Arindam , Nanjundiah Ravi S.
Published: July 2012

This study uses precipitation estimates from the Tropical Rainfall Measuring Mission to quantify the spatial and temporal scales of northward propagation of convection over the Indian monsoon region during boreal summer. Propagating modes of convective systems in the intraseasonal time scales such as the Madden–Julian oscillation can interact with the intertropical convergence zone and bring active and break spells of the Indian summer monsoon. Wavelet analysis was used to quantify the spatial extent (scale) and center of these propagating convective bands, as well as the time period associated with different spatial scales. Results presented here suggest that during a good monsoon year the spatial scale of this oscillation is about 30° centered around 10°N. During weak monsoon years, the scale of propagation decreases and the center shifts farther south closer to the equator. A strong linear relationship is obtained between the center/scale of convective wave bands and intensity of monsoon precipitation over Indian land on the interannual time scale. Moreover, the spatial scale and its center during the break monsoon were found to be similar to an overall weak monsoon year. Based on this analysis, a new index is proposed to quantify the spatial scales associated with propagating convective bands. This automated wavelet-based technique developed here can be used to study meridional propagation of convection in a large volume of datasets from observations and model simulations. The information so obtained can be related to the interannual and intraseasonal variation of Indian monsoon precipitation.
The Role of Ice Cover in Heavy Lake-Effect Snowstorms over the Great Lakes Basin as Simulated by RegCM4
Authors: Vavrus Steve , Notaro Michael , Zarrin Azar
Published: July 2012

A 20-km regional climate model, the Abdus Salam International Centre for Theoretical Physics Regional Climate Model version 4 (ICTP RegCM4), is employed to investigate heavy lake-effect snowfall (HLES) over the Great Lakes Basin and the role of ice cover in regulating these events. When coupled to a lake model and driven with atmospheric reanalysis data between 1976 and 2002, RegCM4 reproduces the major characteristics of HLES. The influence of lake ice cover on HLES is investigated through 10 case studies (2 per Great Lake), in which a simulated heavy lake-effect event is compared with a companion simulation having 100% ice cover imposed on one or all of the Great Lakes. These experiments quantify the impact of ice cover on downstream snowfall and demonstrate that Lake Superior has the strongest, most widespread influence on heavy snowfall and Lake Ontario the least. Ice cover strongly affects a wide range of atmospheric variables above and downstream of lakes during HLES, including snowfall, surface energy fluxes, wind speed, temperature, moisture, clouds, and air pressure. Averaged among the 10 events, complete ice coverage causes major reductions in lake-effect snowfall (>80%) and turbulent heat fluxes over the lakes (>90%), less low cloudiness, lower temperatures, and higher air pressure. Another important consequence is a consistent weakening (30%–40%) of lower-tropospheric winds over the lakes when completely frozen. This momentum reduction further decreases over-lake evaporation and weakens downstream wind convergence, thus mitigating lake-effect snowfall. This finding suggests a secondary, dynamical mechanism by which ice cover affects downstream snowfall during HLES events, in addition to the more widely recognized thermodynamic influence.