bluuebunny/crossref_metadata_2025 huggingface dataset:
The sound of ‘silence’: a framework for researching sensitive issues or marginalised perspectives in health
Authors: Serrant-Green Laura
Published: November 2010

This paper arises from the conceptual framework underpinning a research study focusing on black Caribbean men’s sexual decisions and health behaviour. In investigating these issues the notion of ‘screaming silences’ was developed to unite the theoretical and philosophical approaches that underpinned the research, the experiences of the researcher and participants involved. While ‘screaming silences’ was initially applied to a sexual health and ethnicity context it provides a useful basis for a theoretical framework for researching sensitive issues or the health care needs of marginalised populations. ‘Screaming silences’ (or ‘silences’) define areas of research and experience which are little researched, understood or silenced. ‘Silences’ reflect the unsaid or unshared aspects of how beliefs, values and experiences of (or about) some groups affect their health and life chances. They exposed issues which shape, influence and inform both individual and group understandings of health and health behaviour. This paper presents the notion of ‘screaming silences’ with reference to the original study and maps out a four-stage framework for its utilisation in ethnicities based and sensitive research. It is presented here for use by other researchers as a vehicle for exposing additional perspectives in studies involving sensitive subjects or marginalised populations.
Current and emerging therapies for the management of functional gastrointestinal disorders
Authors: Craig Orla F. , Quigley Eamonn M. M.
Published: November 2010

The functional gastrointestinal disorders are common disorders that are associated with significant quality-of-life impairment and considerable economic burden on the healthcare system. They are frequently associated with a comorbid psychiatric condition; this, together with a striking lack of effective pharmacological therapies, means they represent a considerable therapeutic challenge to the treating physician. In this overview, we examine the evidence to support the use of agents currently used in the management of the more common functional gastrointestinal disorders and review emerging therapies.
The individual-cell-based cryo-chip for the cryopreservation, manipulation and observation of spatially identifiable cells. II: Functional activity of cryopreserved cells
Authors: Afrimzon Elena , Zurgil Naomi , Shafran Yana , Ehrhart Friederike , Namer Yaniv , Moshkov Sergei , Sobolev Maria , Deutsch Assaf , Howitz Steffen , Greuner Martin , Thaele Michael , Meiser Ina , Zimmermann Heiko , Deutsch Mordechai
Published: November 2010

Background

The cryopreservation and thawing processes are known to induce many deleterious effects in cells and might be detrimental to several cell types. There is an inherent variability in cellular responses among cell types and within individual cells of a given population with regard to their ability to endure the freezing and thawing process. The aim of this study was to evaluate the fate of cryopreserved cells within an optical cryo apparatus, the individual-cell-based cryo-chip (i3C), by monitoring several basic cellular functional activities at the resolution of individual cells.

Results

In the present study, U937 cells underwent the freezing and thawing cycle in the i3C device. Then a panel of vital tests was performed, including the number of dead cells (PI staining), apoptotic rate (Annexin V staining), mitochondrial membrane potential (TMRM staining), cytoplasm membrane integrity and intracellular metabolism (FDA staining), as well as post-thawing cell proliferation assays. Cells that underwent the freezing - thawing cycle in i3C devices exhibited the same functional activity as control cells. Moreover, the combination of the multi-parametric analysis at a single cell resolution and the optical and biological features of the device enable an accurate determination of the functional status of individual cells and subsequent retrieval and utilization of the most valuable cells.

Conclusions

The means and methodologies described here enable the freezing and thawing of spatially identifiable cells, as well as the efficient detection of viable, specific, highly biologically active cells for future applications.
Contribution of constitutively proliferating precursor cell subtypes to dentate neurogenesis after cortical infarcts
Authors: Keiner Silke , Walter Josephine , Oberland Julia , Redecker Christoph
Published: November 2010

Background

It is well known that focal ischemia increases neurogenesis in the adult dentate gyrus of the hippocampal formation but the cellular mechanisms underlying this proliferative response are only poorly understood. We here investigated whether precursor cells which constitutively proliferate before the ischemic infarct contribute to post-ischemic neurogenesis. To this purpose, transgenic mice expressing green fluorescent protein (GFP) under the control of the nestin promoter received repetitive injections of the proliferation marker bromodeoxyuridine (BrdU) prior to induction of cortical infarcts. We then immunocytochemically analyzed the fate of these BrdU-positive precursor cell subtypes from day 4 to day 28 after the lesion.

Results

Quantification of BrdU-expressing precursor cell populations revealed no alteration in number of radial glia-like type 1 cells but a sequential increase of later precursor cell subtypes in lesioned animals (type 2a cells at day 7, type 3 cells/immature neurons at day 14). These alterations result in an enhanced survival of mature neurons 4 weeks postinfarct.

Conclusions

Focal cortical infarcts recruit dentate precursor cells generated already before the infarct and significantly contribute to an enhanced neurogenesis. Our findings thereby increase our understanding of the complex cellular mechanisms of postlesional neurogenesis.
A novel genetically-obese rat model with elevated 11beta-hydroxysteroid dehydrogenase type 1 activity in subcutaneous adipose tissue
Authors: Prasad Sakamuri SS Vara , Prashanth Anamthathmakula , Kumar Chodavarapu Pavan , Reddy Sirisha J , Giridharan Nappan V , Vajreswari Ayyalasomayajula
Published: November 2010

11β-hydroxysteroid dehydrogenase type 1 (11β-HSD1) catalyzes the conversion of inactive glucocorticoids to active glucocorticoids and plays an important role in the development of obesity and metabolic syndrome. 11β-HSD1 activity is lower in liver and higher in omental adipose tissue of obese rodent models like obese zucker rats, Ob/Ob and db/db mice. Here, we report the 11β-HSD1 activity in liver and adipose tissue of lean and obese rats of WNIN/Ob strain, a new genetic rat model of obesity. 11β-HSD1 activity in liver, omental and subcutaneous adipose tissues of 3 month-old male WNIN/Ob lean and obese rats was assayed. As observed in other rodent models, 11β-HSD1 activity was lower in liver and higher in omental adipose tissue. In contrast to other rodent obese models, WNIN/Ob obese rats had elevated 11β-HSD1 activity in subcutaneous adipose tissue, which is in line with the observation in human obesity. Here, we conclude that dysregulation of 11β-HSD1 in WNIN/Ob obese rat model is identical to human obesity, which makes it an excellent model for studying the effect of 11β-HSD1 inhibitors in ameliorating obesity and metabolic syndrome.
Temporomandibular joint dysfunction and orthognathic surgery: a retrospective study
Authors: Dujoncquoy Jean-Pascal , Ferri Joël , Raoul Gwénael , Kleinheinz Johannes
Published: November 2010

Background

Relations between maxillo-mandibular deformities and TMJ disorders have been the object of different studies in medical literature and there are various opinions concerning the alteration of TMJ dysfunction after orthognathic surgery. The purpose of the present study was to evaluate TMJ disorders changes before and after orthognathic surgery, and to assess the risk of creating new TMJ symptoms on asymptomatic patients.

Methods

A questionnaire was sent to 176 patients operated at the Maxillo-Facial Service of the Lille's 2 Universitary Hospital Center (Chairman Pr Joël Ferri) from 01.01.2006 to 01.01.2008. 57 patients (35 females and 22 males), age range from 16 to 65 years old, filled the questionnaire. The prevalence and the results on pain, sounds, clicking, joint locking, limited mouth opening, and tenseness were evaluated comparing different subgroups of patients.

Results

TMJ symptoms were significantly reduced after treatment for patients with pre-operative symptoms. The overall subjective treatment outcome was: improvement for 80.0% of patients, no change for 16.4% of patients, and an increase of symptoms for 3.6% of them. Thus, most patients were very satisfied with the results. However the appearance of new onset of TMJ symptoms is common. There was no statistical difference in the prevalence of preoperative TMJ symptoms and on postoperative results in class II compared to class III patients.

Conclusions

These observations demonstrate that: there is a high prevalence of TMJ disorders in dysgnathic patients; most of patients with preoperative TMJ signs and symptoms can improve TMJ dysfunction and pain levels can be reduced by orthognathic treatment; a percentage of dysgnathic patients who were preoperatively asymptomatic can develop TMJ disorders after surgery but this risk is low.
Bilateral heterochronic spontaneous hemothorax caused by pulmonary arteriovenous malformation in a gravid: A case report
Authors: Zhao Yinghao , Li Guang-Yu , Yang Zhiguang , Zhang Peng , Zhang Kun , Shao Guoguang
Published: November 2010

Bilateral heterochronic spontaneous hemothorax as a result of pulmonary ateriovenous malformation is a very rarely happened disease. A 34-year-old woman presented major symptoms with right-sided chest pain and shortness of breath. The following contrast-enhanced computed tomographic scan of the chest showed a large amount of fluid in the right thorax with mediastinal shift, but without major vessel injury and 2 small dense opacities in the apical segment of the right lower lobe and in the posterior aspect of the left lower lobe. The patient underwent local resection of the right lower lobe. The pulmonary ateriovenous malformation was further identified by pathological examination. One month after she was discharged home, the symptoms described above recurred. A follow-up computed tomographic scan of the chest showed a large amount of fluid in the left thorax. During the emergency operation, we found a bullous lesion in the left lower lobe and a small blood vessel overlying the lesion that was actively bleeding. As stated above, local resection of the left lower lobe was performed once more. Pathological result was the same as observed previously. There were no postoperative complications and she was discharged from the hospital after two weeks. Two months later, she successfully delivered a healthy female infant. Up to now, regular follow-up observation has shown her to be perfectly asymptomatic.
Human papillomavirus-16 presence and physical status in lung carcinomas from Asia
Authors: Aguayo Francisco , Anwar Muhammad , Koriyama Chihaya , Castillo Andres , Sun Quanfu , Morewaya Jacob , Eizuru Yoshito , Akiba Suminori
Published: November 2010

Background

Although human papillomavirus (HPV) genome has been detected in lung cancer, its prevalence is highly variable around the world. Higher frequencies have been reported in far-east Asian countries, when compared with European countries. The present study analysed the HPV-16 presence in 60 lung carcinomas from the Asian countries China, Pakistan and Papua New Guinea.

Results

HPV-16 was present in 8/59 (13%) samples. According to histological type, HPV-16 was detected in 8/18 (44%) squamous cell carcinomas (SQCs), which were mainly from Pakistan; 0/38 (0%) adenocarcinomas (ACs), which were mainly from China; and in 0/4 (0%) small cell carcinomas (SCLCs). The observed histological difference was statistically significant (p < 0.001). HPV-16 viral load was also determined using real-time polymerase chain reaction (qRT-PCR); it ranged between 411 to 2345 copies/100 ng of genomic DNA. HPV-16 genome was found integrated into the host genome in every HPV-16 positive carcinoma.

Conclusion

These results support the notion that HPV-16 infection is highly associated with SQCs in Pakistan. Our results show a frequent HPV-16 integration in SQCs, although the low viral load casts doubt respect a direct etiological role of HPV in lung carcinomas from Asia. Additional HPV-16 characterization is necessary to establish a direct or indirect etiological role of HPV in this malignancy.
A multi-level study of recombinant Pichia pastoris in different oxygen conditions
Authors: Baumann Kristin , Carnicer Marc , Dragosits Martin , Graf Alexandra B , Stadlmann Johannes , Jouhten Paula , Maaheimo Hannu , Gasser Brigitte , Albiol Joan , Mattanovich Diethard , Ferrer Pau
Published: November 2010

Background

Yeasts are attractive expression platforms for many recombinant proteins, and there is evidence for an important interrelation between the protein secretion machinery and environmental stresses. While adaptive responses to such stresses are extensively studied in Saccharomyces cerevisiae, little is known about their impact on the physiology of Pichia pastoris. We have recently reported a beneficial effect of hypoxia on recombinant Fab secretion in P. pastoris chemostat cultivations. As a consequence, a systems biology approach was used to comprehensively identify cellular adaptations to low oxygen availability and the additional burden of protein production. Gene expression profiling was combined with proteomic analyses and the 13C isotope labelling based experimental determination of metabolic fluxes in the central carbon metabolism.

Results

The physiological adaptation of P. pastoris to hypoxia showed distinct traits in relation to the model yeast S. cerevisiae. There was a positive correlation between the transcriptomic, proteomic and metabolic fluxes adaptation of P. pastoris core metabolism to hypoxia, yielding clear evidence of a strong transcriptional regulation component of key pathways such as glycolysis, pentose phosphate pathway and TCA cycle. In addition, the adaptation to reduced oxygen revealed important changes in lipid metabolism, stress responses, as well as protein folding and trafficking.

Conclusions

This systems level study helped to understand the physiological adaptations of cellular mechanisms to low oxygen availability in a recombinant P. pastoris strain. Remarkably, the integration of data from three different levels allowed for the identification of differences in the regulation of the core metabolism between P. pastoris and S. cerevisiae. Detailed comparative analysis of the transcriptomic data also led to new insights into the gene expression profiles of several cellular processes that are not only susceptible to low oxygen concentrations, but might also contribute to enhanced protein secretion.
Macrodystrophia lipomatosa: four case reports
Authors: Khan Rizwan A , Wahab Shagufta , Ahmad Ibne , Chana Rajendra S
Published: November 2010

Aim

Macrodystrophia lipomatosa is a rare cause of gigantism of limb which can be confused with other common causes like congenital lymphedema. It presents usually with loss of function and cosmetic problems. Four cases are described with emphasis on clinical presentation, differential diagnoses, imaging and treatment options.

Methods & Results

Four patients of macrodystrophia lipomatosa were thoroughly examined and subjected to investigations.

Conclusion

Besides diligent clinical examination, imaging and histopathology are crucial in clinching the diagnosis.
Distance between homologous chromosomes results from chromosome positioning constraints
Authors: Heride Claire , Ricoul Michelle , Kiêu Kien , von Hase Johann , Guillemot Vincent , Cremer Christoph , Dubrana Karine , Sabatier Laure
Published: November 2010

The organization of chromosomes is important for various biological processes and is involved in the formation of rearrangements often observed in cancer. In mammals, chromosomes are organized in territories that are radially positioned in the nucleus. However, it remains unclear whether chromosomes are organized relative to each other. Here, we examine the nuclear arrangement of 10 chromosomes in human epithelial cancer cells by three-dimensional FISH analysis. We show that their radial position correlates with the ratio of their gene density to chromosome size. We also observe that inter-homologue distances are generally larger than inter-heterologue distances. Using numerical simulations taking radial position constraints into account, we demonstrate that, for some chromosomes, radial position is enough to justify the inter-homologue distance, whereas for others additional constraints are involved. Among these constraints, we propose that nucleolar organizer regions participate in the internal positioning of the acrocentric chromosome HSA21, possibly through interactions with nucleoli. Maintaining distance between homologous chromosomes in human cells could participate in regulating genome stability and gene expression, both mechanisms that are key players in tumorigenesis.
REGγ modulates p53 activity by regulating its cellular localization
Authors: Liu Jian , Yu Guowu , Zhao Yanyan , Zhao Dengpan , Wang Ying , Wang Lu , Liu Jiang , Li Lei , Zeng Yu , Dang Yongyan , Wang Chuangui , Gao Guang , Long Weiwen , Lonard David M. , Qiao Shanlou , Tsai Ming-Jer , Zhang Bianhong , Luo Honglin , Li Xiaotao
Published: November 2010

The proteasome activator REGγ mediates a shortcut for the destruction of intact mammalian proteins. The biological roles of REGγ and the underlying mechanisms are not fully understood. Here we provide evidence that REGγ regulates cellular distribution of p53 by facilitating its multiple monoubiquitylation and subsequent nuclear export and degradation. We also show that inhibition of p53 tetramerization by REGγ might further enhance cytoplasmic relocation of p53 and reduce active p53 in the nucleus. Furthermore, multiple monoubiquitylation of p53 enhances its physical interaction with HDM2 and probably facilitates subsequent polyubiquitylation of p53, suggesting that monoubiquitylation can act as a signal for p53 degradation. Depletion of REGγ sensitizes cells to stress-induced apoptosis, validating its crucial role in the control of apoptosis, probably through regulation of p53 function. Using a mouse xenograft model, we show that REGγ knockdown results in a significant reduction of tumor growth, suggesting an important role for REGγ in tumor development. Our study therefore demonstrates that REGγ-mediated inactivation of p53 is one of the mechanisms involved in cancer progression.
CEACAM1: a key regulator of vascular permeability
Authors: Nouvion Anne-Laure , Oubaha Malika , LeBlanc Sarah , Davis Elaine C. , Jastrow Holger , Kammerer Robert , Breton Valérie , Turbide Claire , Ergun Suleyman , Gratton Jean-Philippe , Beauchemin Nicole
Published: November 2010

Carcinoembryonic antigen cell adhesion molecule-1 (CEACAM1) is an immunoglobulin-like cell surface co-receptor expressed on epithelial, hematopoietic and endothelial cells. CEACAM1 functions as an adhesion molecule, mainly binding to itself or other members of the CEA family. We and others have previously shown that CEACAM1 is crucial for in vivo vascular integrity during ischemic neo-vascularization. Here, we have deciphered the roles of CEACAM1 in normal and pathological vascularization. We have found that Ceacam1−/− mice exhibit a significant increase in basal vascular permeability related to increased basal Akt and endothelial nitric oxide synthase (eNOS) activation in primary murine lung endothelial cells (MLECs). Moreover, CEACAM1 deletion in MLECs inhibits VEGF-mediated nitric oxide (NO) production, consistent with defective VEGF-dependent in vivo permeability in Ceacam1−/− mice. In addition, Ceacam1-null mice exhibit increased permeability of tumor vasculature. Finally, we demonstrate that CEACAM1 is tyrosine-phosphorylated upon VEGF treatment in a SHP-1- and Src-dependent manner, and that the key residues of the long cytoplasmic domain of CEACAM1 are crucial for CEACAM1 phosphorylation and NO production. This data represents the first report, to our knowledge, of a functional link between CEACAM1 and the VEGFR2/Akt/eNOS-mediated vascular permeability pathway.
Adverse Reactions/Medication Safety: Beyond the Beers Criteria: A Comparative Overview of Explicit Criteria
Authors: Levy Hedva Barenholtz , Marcus Esther-Lee , Christen Catherine
Published: November 2010

Objective:

To provide a comparative overview of explicit criteria that have been developed since 2003 for inappropriate prescribing in older adults and to contrast these newer criteria with the most recent Beers criteria, published in 2003.

Data Sources:

MEDLINE and Google Scholar searches were performed from 2003 through July 2010. Within MEDLINE. MeSH terms included aged, drug prescriptions, medication errors, and polypharmacy. Free-text search terms included elderly, guideline adherence, inappropriate prescribing, and medications. Related articles, as identified by MEDLINE, were used as well. Free-text search was performed on Google Scholar, using “potentially inappropriate prescribing elderly.” Additional articles were identified in reference lists of key articles,

Study Selection and Data Extraction:

Studies were selected if they were published after the most recent revision of the Beers criteria in 2003 and addressed the development and application of explicit criteria for the elderly. We independently reviewed pertinent literature to extract key information.

Data Synthesis:

The first explicit criteria published were the Beers criteria, and most research regarding inappropriate medication use applied these criteria. Criteria developed subsequent to the Beers criteria include the French Consensus Panel list, STOPP (Screening Tool of Older Persons' Prescription) and START (Screening Tool to Alert doctors to Right Treatment), the Australian Prescribing Indicators tool, and the Norwegian General Practice Criteria. Newer criteria offer several improvements on the Beers criteria, namely drug-drug interactions, omission of potentially beneficial therapy, and more broadly applicable criteria across international borders.

Conclusions:

Although no criteria may ever be globally applicable, STOPP and START make significant advances. Regional drug availability, economic considerations, and clinical practice patterns impact criteria selection. Research to validate the several newer criteria in various practice settings and to explore the effect of adhering to the guidelines on patient outcomes is warranted. Data from such research will aid practitioners in identifying preferred criteria.
Customer Satisfaction, Analyst Stock Recommendations, and Firm Value
Authors: Luo Xueming , Homburg Christian , Wieseke Jan
Published: November 2010

Although managers are interested in the financial value of customers and researchers have pointed out the importance of stock analysts who advise investors, no studies to date have explored the implications of customer satisfaction for analyst stock recommendations. Using a large-scale longitudinal data set, the authors find that positive changes in customer satisfaction not only improve analyst recommendations but also lower dispersion in those recommendations for the firm. These effects are stronger when product market competition is high and financial market uncertainty is large. In addition, analyst recommendations at least partially mediate the effects of changes in satisfaction on firm abnormal return, systematic risk, and idiosyncratic risk. Analyst recommendations represent a mechanism through which customer satisfaction affects firm value. Thus, if analysts pay attention to Main Street customer satisfaction, Wall Street investors should have good reason to listen and follow. Overall, this research reveals the impact of satisfaction on analyst-based outcomes and firm value metrics and calls attention to the construct of customer satisfaction as a key intangible asset for the investor community.
Quantity-Discount-Dependent Consumer Preferences and Competitive Nonlinear Pricing
Authors: Gu Zheyin (Jane) , Yang Sha
Published: November 2010

Producers of consumer packaged goods often offer several package sizes of the same product and charge a lower unit price for a larger size. In this article, the authors investigate the “quantity-discount effect,” or the phenomenon that consumers derive transaction utility from the unit price difference between a small and a large package size of the same product. The authors propose a modeling framework composed of a demand-side model and a supply-side model. The empirical results suggest that quantity-discount-induced gains or losses have a significant impact on consumer buying behavior. The authors also find a substantial amount of structural heterogeneity; that is, some consumers perceive quantity discounts as gains, whereas others perceive quantity discounts as losses. Conversely, the supply-side analysis suggests that manufacturers in the empirical application do not consider quantity-discount effects when setting prices. Through a series of policy experiments, the authors show that by accounting for quantity-discount-dependent consumer preferences, manufacturers can design more effective nonlinear pricing schemes and obtain greater profits.
How and when Alphanumeric Brand Names Affect Consumer Preferences
Authors: Gunasti Kunter , Ross William T.
Published: November 2010

This research develops a taxonomy of alphanumeric brand names (ABs) based on the alignment between the brand names and their links to products and attributes. Five empirical studies reveal that ABs have systematic effects on consumers’ product choices, moderated by consumers’ need for cognition, the availability of product attribute information, and the taxonomic category of the AB. In an identical choice set, the choice share of a product option whose brand name takes a higher versus lower numeric portion (e.g., X-200 versus X-100) increases, and it is preferred more even when it is objectively inferior to other choice alternatives. Consumers with low need for cognition use “the higher, the better” heuristic to select options labeled with ABs and choose brands with higher numeric portions. Consumers with high need for cognition process ABs more systematically and make inferences about attribute values based on brand name–attribute correlations. The effects of ABs on consumer preferences are prevalent for most technical products, even when consumers do not know the product category or meanings of attributes.
Strengthening of Top-Down Frontal Cognitive Control Networks Underlying the Development of Inhibitory Control: A Functional Magnetic Resonance Imaging Effective Connectivity Study
Authors: Hwang Kai , Velanova Katerina , Luna Beatriz
Published: November 2010

The ability to voluntarily inhibit responses to task-irrelevant stimuli, which is a fundamental component of cognitive control, has a protracted development through adolescence. Previous human developmental imaging studies have found immaturities in localized brain activity in children and adolescents. However, little is known about how these regions integrate with age to form the distributed networks known to support cognitive control. In the present study, we used Granger causality analysis to characterize developmental changes in effective connectivity underlying inhibitory control (antisaccade task) compared with reflexive responses (prosaccade task) in human participants. By childhood, few top-down connectivities were evident with increased parietal interconnectivity. By adolescence, connections from prefrontal cortex increased and parietal interconnectivity decreased. From adolescence to adulthood, there was evidence of increased number and strength of frontal connections to cortical regions as well as subcortical regions. Together, results suggest that developmental improvements in inhibitory control may be supported by age-related enhancements in top-down effective connectivity between frontal, oculomotor, and subcortical regions.
Control of CA3 Output by Feedforward Inhibition Despite Developmental Changes in the Excitation–Inhibition Balance
Authors: Torborg Christine L. , Nakashiba Toshiaki , Tonegawa Susumu , McBain Chris J.
Published: November 2010

In somatosensory cortex, the relative balance of excitation and inhibition determines how effectively feedforward inhibition enforces the temporal fidelity of action potentials. Within the CA3 region of the hippocampus, glutamatergic mossy fiber (MF) synapses onto CA3 pyramidal cells (PCs) provide strong monosynaptic excitation that exhibit prominent facilitation during repetitive activity. We demonstrate in the juvenile CA3 that MF-driven polysynaptic IPSCs facilitate to maintain a fixed EPSC-IPSC ratio during short-term plasticity. In contrast, in young adult mice this MF-driven polysynaptic inhibitory input can facilitate or depress in response to short trains of activity. Transgenic mice lacking the feedback inhibitory loop continue to exhibit both facilitating and depressing polysynaptic IPSCs, indicating that this robust inhibition is not caused by the secondary engagement of feedback inhibition. Surprisingly, eliminating MF-driven inhibition onto CA3 pyramidal cells by blockade of GABAAreceptors did not lead to a loss of temporal precision of the first action potential observed after a stimulus but triggered in many cases a long excitatory plateau potential capable of triggering repetitive action potential firing. These observations indicate that, unlike other regions of the brain, the temporal precision of single MF-driven action potentials is dictated primarily by the kinetics of MF EPSPs, not feedforward inhibition. Instead, feedforward inhibition provides a robust regulation of CA3 PC excitability across development to prevent excessive depolarization by the monosynaptic EPSP and multiple action potential firings.
Acute Inhibition of PKA Activity at Old Ages Ameliorates Age-Related Memory Impairment inDrosophila
Authors: Yamazaki Daisuke , Horiuchi Junjiro , Miyashita Tomoyuki , Saitoe Minoru
Published: November 2010

Age-related memory impairment (AMI) is a critical and debilitating phenotype of brain aging, but its underlying molecular mechanisms are largely unknown. InDrosophila, AMI is highly correlated with PKA activity in the mushroom bodies, neural centers essential for forming associative olfactory memories. Heterozygous mutations inDC0(DC0/+), which encodes the major catalytic subunit of PKA (PKAc), significantly suppress AMI, while overexpression of aDC0transgene (DC0+) impairs memory and occludes AMI. PKA activity does not increase upon aging, and it is not clear whether AMI is caused by continual PKA activity throughout aging or by an acute increase in PKA signaling at old ages. Likewise, it is not clear whether AMI can be ameliorated by acute interventions at old ages or whether continuous intervention throughout aging is necessary. We show here that an acute increase in PKA activity at old ages is sufficient to restore normal AMI inDC0/+ flies. Conversely, acute expression of a PKA inhibitory peptide at old ages is sufficient to reverse AMI in a wild-type background. These results indicate that AMI inDrosophilais caused by an age-dependent change in PKA-dependent signaling that can be reversed by acute interventions at old ages.
Spontaneous Network Events Driven by Depolarizing GABA Action in Neonatal Hippocampal Slices are Not Attributable to Deficient Mitochondrial Energy Metabolism
Authors: Ruusuvuori Eva , Kirilkin Ilya , Pandya Nikhil , Kaila Kai
Published: November 2010

In two recent papers (Rheims et al., 2009; Holmgren et al., 2010), Zilberter and coworkers argue that the well known depolarizing GABA actions that take place at the cellular and network level in the neonatal hippocampus and neocortexin vitroare pathophysiological phenomena, attributable to deficient mitochondrial energy metabolism. In their experiments, supplementing the glucose-containing solution with weak-acid substrates of mitochondrial energy metabolism (such as β-hydroxy-butyrate, lactate, or pyruvate) abolished the spontaneous network events (giant depolarizing potentials; GDPs) and the underlying depolarizing actions of GABA. In this study, we made electrophysiological recordings of GDPs and monitored the mitochondrial membrane potential (Ψm) and intracellular pH (pHi) in CA3 neurons in neonatal rat hippocampal slices. Supplementing the standard physiological solution withl-lactate did not produce a change in Ψm, whereas withdrawal of glucose, in the presence or absence ofl-lactate, was followed by a pronounced depolarization of Ψm. Furthermore,d-lactate (a poor substrate of mitochondrial metabolism) caused a prompt inhibition in GDP frequency which was similar to the effect ofl-lactate. The suppression of GDPs was strictly proportional to the fall in pHicaused by weak carboxylic acids (l-lactate,d-lactate, or propionate) or by an elevated CO2. The main conclusions of our work are that the inhibitory effect ofl-lactate on GDPs is not mediated by mitochondrial energy metabolism, and that glucose at its standard 10 mmconcentration is an adequate energy substrate for neonatal neuronsin vitro. Notably, changes in pHiappear to have a very powerful modulatory effect on GDPs.
Metzincin Proteases and Their Inhibitors: Foes or Friends in Nervous System Physiology?
Authors: Rivera Santiago , Khrestchatisky Michel , Kaczmarek Leszek , Rosenberg Gary A. , Jaworski Diane M.
Published: November 2010

Members of the metzincin family of metalloproteinases have long been considered merely degradative enzymes for extracellular matrix molecules. Recently, however, there has been growing appreciation for these proteinases and their endogenous inhibitors, tissue inhibitors of metalloproteinases (TIMPs), as fine modulators of nervous system physiology and pathology. Present all along the phylogenetic tree, in all neural cell types, from the nucleus to the synapse and in the extracellular space, metalloproteinases exhibit a complex spatiotemporal profile of expression in the nervous parenchyma and at the neurovascular interface. The irreversibility of their proteolytic activity on numerous biofactors (e.g., growth factors, cytokines, receptors, DNA repair enzymes, matrix proteins) is ideally suited to sustain structural changes that are involved in physiological or postlesion remodeling of neural networks, learning consolidation or impairment, neurodegenerative and neuroinflammatory processes, or progression of malignant gliomas. The present review provides a state of the art overview of the involvement of the metzincin/TIMP system in these processes and the prospects of new therapeutic strategies based on the control of metalloproteinase activity.
Long-Distance Axon Regeneration in the Mature Optic Nerve: Contributions of Oncomodulin, cAMP, andptenGene Deletion
Authors: Kurimoto Takuji , Yin Yuqin , Omura Kumiko , Gilbert Hui-ya , Kim Daniel , Cen Ling-Ping , Moko Lilamarie , Kügler Sebastian , Benowitz Larry I.
Published: November 2010

The inability of retinal ganglion cells (RGCs) to regenerate damaged axons through the optic nerve has dire consequences for victims of traumatic nerve injury and certain neurodegenerative diseases. Several strategies have been shown to induce appreciable regenerationin vivo, but the regrowth of axons through the entire optic nerve and on into the brain remains a major challenge. We show here that the induction of a controlled inflammatory response in the eye, when combined with elevation of intracellular cAMP and deletion of the gene encodingpten(phosphatase and tensin homolog), enables RGCs to regenerate axons the full length of the optic nerve in mature mice; approximately half of these axons cross the chiasm, and a rare subset (∼1%) manages to enter the thalamus. Consistent with our previous findings, the axon-promoting effects of inflammation were shown to require the macrophage-derived growth factor Oncomodulin (Ocm). Elevation of cAMP increased the ability of Ocm to bind to its receptors in the inner retina and augmented inflammation-induced regeneration twofold. Inflammation combined with elevated cAMP and PTEN deletion increased activation of the phosphatidylinositol 3-kinase and mitogen-activated protein kinase signaling pathways and augmented regeneration ∼10-fold over the level induced by eitherptendeletion or Zymosan alone. Thus, treatments that synergistically alter the intrinsic growth state of RGCs produce unprecedented levels of axon regeneration in the optic nerve, a CNS pathway long believed to be incapable of supporting such growth.
Ion Jump Dynamics in Nanoscopic Subvolumes Analyzed by Electrostatic Force Spectroscopy
Authors: Schirmeisen Andre , Taskiran Ahmet , Bracht Hartmut , Roling Bernhard
Published: November 2010

A nanoscopic technique based on electrostatic force spectroscopy in the time domain is introduced. This technique is used to characterize the ion dynamics in nanoscale subvolumes of solid electrolytes. Nanoscopic polarization spots can be created and directly visualized, and their time evolution can be studied. In the case of partially crystallized glass ceramics, the dynamic processes in different phases (glassy, crystalline and interface) can be distinguished and their activation energies and pre-exponential factors can be quantified. By applying grid-type spectroscopic measurements, maps of the local relaxation strength are obtained, giving information about the spatial distribution of the glassy and crystalline phase.
Salt-in-Polymer Electrolytes for Lithium Ion Batteries Based on Organo-Functionalized Polyphosphazenes and Polysiloxanes
Authors: Burjanadze Marina , Karatas Yunus , Kaskhedikar Nitin , Kogel Lutz M. , Kloss Sebastian , Gentschev Ann-Christin , Hiller Martin M. , Müller Romek A. , Stolina Raphael , Vettikuzha Preeya , Wiemhöfer Hans-Dieter
Published: November 2010

An overview is given on polymer electrolytes based on organo-functionalized polyphosphazenes and polysiloxanes. Chemical and electrochemical properties are discussed with respect to the synthesis, the choice of side groups and the goal of obtaining membranes and thin films that combine high ionic conductivity and mechanical stability. Electrochemical stability, concentration polarization and the role of transference numbers are discussed with respect to possible applications in lithium batteries. It is shown that the ionic conductivities of salt-in-polymer membranes without additives and plasticizers are limited to maximum conductivities around 10-4S/cm. Nevertheless, a straightforward strategy based on additives can increase the conductivities to at least 10-3S/cm and maybe further. In this context, the future role of polymers for safe, alternative electrolytes in lithium batteries will benefit from concepts based on polymeric gels, composites and hybrid materials. Presently developed polymer electrolytes with oligoether sidechains are electrochemically stable in the potential range 0–4.5V (vs. Li/Li+ reference).
Effect of CTAB Micelle on the Oxidation of L-Leucine by N-Bromophthalimide: a Kinetic Study
Authors: Katre Yokraj , Goyal Namita , Singh Ajaya Kumar
Published: November 2010

The effect of cationic surfactant cetyltrimethylammonium bromide (CTAB) on the oxidation of L-leucine by N-bromophthalimide (NBP) has been studied at 308 K. The reaction exhibits first order dependence on NBP and L-leucine and negative and fractional order dependence on HClO4. The effects of KCl, KBr, phthalimide and mercuric acetate have also been studied and summarized. The rate of reaction increased with an increase in dielectric constant of the medium. CTAB strongly catalyzes the reaction and typical k
obs and CTAB profile was observed, i.e., with a progressive increase in CTAB, the reaction rate increased and after achieving a peak k
obs decreased at higher concentrations of CTAB. The results are treated quantitatively in terms of “Piszkiewicz” and “Raghvan and Srinivasan's” models. The various activation parameters in presence and absence of CTAB have been also evaluated. A suitable mechanism consistent with the experimental findings has been proposed. The rate constant in micellar phase k
M, cooperativity index (n), binding constant (K
1 and K
2) have been computed.
Kinetic Analysis of High-Rate and of Low-Rate Regimes in CO Oxidation on Pt Group Metals: Evidence for Vibrational Excitation of the O-Rich Adlayer and for Thermal Equilibrium of the CO-Rich Phase
Authors: Molinari Ettore , Tomellini Massimo
Published: November 2010

Proper reduction of available literature data on the heterogeneous CO+O2 reaction on Pt group metals allows one to describe the parallel process of CO desorption, in extended intervals of temperature and gas composition, both in the High-Rate regime of an oxygen rich surface and in the Low-Rate regime of a CO rich surface. The outcome of this analysis is the determination of “apparent” as well as of “true” activation energies for both CO oxidation and desorption and their dependence on surface coverage by O or by CO-adspecies. The conclusion is reached that non-equilibrium conditions of vibrational excitation of the adlayers prevail in the HR regions, while Boltzmann equilibrium characterizes LR regimes in extended temperature and pressure intervals. These results have been discussed in the framework of a theoretical model that predicts hyperthermal vibrational states of the adlayer, which depend on the efficiency of energy dissipation into the metal.
Automedicação em adultos de baixa renda no município de São Paulo
Authors: Schmid Bianca , Bernal Regina , Silva Nilza Nunes
Published: November 2010

OBJETIVO: Estimar a proporção de automedicação em adultos de baixa renda e identificar fatores associados. MÉTODOS: Foram utilizados dados de inquérito populacional realizado no município de São Paulo em 2005, cujo plano amostral incluiu dois domínios, favela e não favela, com amostragem por conglomerados em dois estágios, totalizando 3.226 indivíduos elegíveis. Além de características sociodemográficas e econômicas, foram analisados: uso de medicamentos nos 15 dias anteriores à entrevista, tipo de acesso (gratuito, comprado ou outra) aos medicamentos e os tipos de morbidades (crônicas ou agudas) tratadas, em análise de regressão logística múltipla. RESULTADOS: A proporção de automedicação foi de 27% a 32%. Automedicação esteve fortemente associada à morbidade aguda, ao acesso ao medicamento por compra, à idade menor que 47 anos e medicamentos do grupo terapêutico que atuam no sistema nervoso central. O grupo que atua no sistema nervoso central foi o mais utilizado na automedicação. CONCLUSÕES: O acesso gratuito aos medicamentos mostrou-se fator de proteção para a automedicação. A distribuição de medicamentos e o atendimento adequado devem ser considerados para orientação e redução dos riscos que o uso irracional de medicamentos pode gerar à saúde.
Leak detection by inverse transient analysis in an experimental PVC pipe system
Authors: Soares Alexandre Kepler , Covas Dídia I. C. , Reis Luisa Fernanda R.
Published: November 2010

Leakage reduction in water supply systems and distribution networks has been an increasingly important issue in the water industry since leaks and ruptures result in major physical and economic losses. Hydraulic transient solvers can be used in the system operational diagnosis, namely for leak detection purposes, due to their capability to describe the dynamic behaviour of the systems and to provide substantial amounts of data. In this research work, the association of hydraulic transient analysis with an optimisation model, through inverse transient analysis (ITA), has been used for leak detection and its location in an experimental facility containing PVC pipes. Observed transient pressure data have been used for testing ITA. A key factor for the success of the leak detection technique used is the accurate calibration of the transient solver, namely adequate boundary conditions and the description of energy dissipation effects since PVC pipes are characterised by a viscoelastic mechanical response. Results have shown that leaks were located with an accuracy between 4–15% of the total length of the pipeline, depending on the discretisation of the system model.
On the coefficients of an asymptotic expansion related to Somos' quadratic recurrence constant
Authors: Nemes Gergő
Published: November 2010

In this paper we study the coefficients of an asymptotic expansion related to
Somos' Quadratic Recurrence Constant. We develop recurrence relations and an
asymptotic estimation for them. We also present some results which show that
these coefficients are related to the Ordered Bell Numbers.
An American Construction of European Education Space
Authors: Silova Iveta , Brehm William C.
Published: November 2010

The construction of the European education space has typically been attributed to European education policy makers, institutions, and networks. Rarely do scholars consider the role of outside, non-European actors in shaping the terrain of European education thought and practice. This article considers the construction of the European education space as a borderless project with multidirectional flows of ideas, policies, and academics. While this project has created an intellectual space for the emergence of new theoretical insights and policy instruments within Europe, it has also had inevitable consequences for the study of comparative education outside Europe. This article explores how American scholars have attempted to influence the development of comparative education as a field in the United States by purposefully constructing specific notions of European education during the cold war (1969–85). Drawing on content analysis of comparative education scholarship in Western European Education — a journal published in the United States — this article discusses the role of journal editors in the construction of European education spaces in order to advance not only a marginalized geographical area of study within the expanding American field of comparative education, but also a methodological vision for the future of comparative education, one free of positivist techniques, quantitative methodologies, and modernization ideologies.
Mediation in Local Educational Governance: The Educating Cities Movement in a Portuguese Town
Authors: Lúcio Joana , Neves Tiago
Published: November 2010

Educational processes have had to deal with the significant changes that have been occurring throughout the world, at different levels, in the last few decades. The Educating Cities movement, which has been followed by cities from all over the world — from Rwanda to Denmark, through Mexico, Canada, Australia, South Korea and Italy — is an attempt to deal with such changes. The movement defines the deepening of the practice of democratic values as the greatest challenge of the twenty-first century. This article explores the role of social and educational mediation in the Educating Cities movement. Its empirical focus is on some of the experiences of the cities that belong to this network, with a special emphasis on the city of Porto, Portugal.
Medical and physical predictors of localized provoked vulvodynia
Authors: Bohm‐Starke Nina
Published: November 2010

Vulvodynia in young women is a significant clinical challenge. This overview focuses on localized provoked vulvodynia (LPV) with regard to medical and physical predictors of the condition. Several causative factors have been proposed and one major conceptual issue is the role of inflammation. Trauma to the vestibular mucosa causes an initial inflammatory response which may result in peripheral and central pain sensitization. In women with LPV, evidence of mucosal nerve fiber proliferation and enhanced systemic pain perception has been found. A dysfunction of the pelvic floor muscles is common and many patients also suffer from other bodily pain. In general, the level of scientific quality in published studies on vulvodynia is low. Further research on epidemiology, etiology and conduction of clinical trials with high evidence grade is desired.