bluuebunny/crossref_metadata_2025_split huggingface dataset:
Hydrogen peroxide affects contractile activity and anti‐oxidant enzymes in rat uterus
Authors: Appiah I , Milovanovic S , Radojicic R , Nikolic‐Kokic A , Orescanin‐Dusic Z , Slavic M , Trbojevic S , Skrbic R , Spasic MB , Blagojevic D 
Published: November 2009

Background and purpose:  The effects of hydrogen peroxide (H2O2) on uterine smooth muscle are not well studied. We have investigated the effect and the mechanism of action of exogenous hydrogen peroxide on rat uteri contractile activity [spontaneous and calcium ion (Ca2+)‐induced] and the effect of such treatment on anti‐oxidative enzyme activities.Experimental approach:  Uteri were isolated from virgin Wistar rats and suspended in an organ bath. Uteri were allowed to contract spontaneously or in the presence of Ca2+ (6 mM) and treated with H2O2 (2 µM–3 mM) over 2 h. Anti‐oxidative enzyme activities (manganese superoxide dismutase‐MnSOD, copper‐zinc superoxide dismutase‐CuZnSOD, catalase‐CAT, glutathione peroxidase‐GSHPx and glutathione reductase‐GR) in H2O2‐treated uteri were compared with those in uteri immediately frozen after isolation or undergoing spontaneous or Ca2+‐induced contractions, without treatment with H2O2. The effect of inhibitors (propranolol, methylene blue, L‐NAME, tetraethylamonium, glibenclamide and 4‐aminopyridine) on H2O2‐mediated relaxation was explored.Key results:  H2O2 caused concentration‐dependent relaxation of both spontaneous and Ca2+‐induced uterine contractions. After H2O2 treatment, GSHPx and MnSOD activities were increased, while CuZnSOD and GR (In Ca2+‐induced rat uteri) were decreased. Nω‐nitro‐L‐arginine methyl ester antagonized the effect of H2O2 on Ca2+‐induced contractions. H2O2‐induced relaxation was not affected by propranolol, potentiated by methylene blue and antagonized by tetraethylamonium, 4‐aminopyridine and glibenclamide, with the last compound being the least effective.Conclusions and implications:  H2O2 induced dose‐dependent relaxation of isolated rat uteri mainly via changes in voltage‐dependent potassium channels. Decreasing generation of reactive oxygen species by stimulation of anti‐oxidative pathways may lead to new approaches to the management of dysfunctional uteri.
[6S]‐5‐methyltetrahydrofolate increases plasma folate more effectively than folic acid in women with the homozygous or wild‐type 677C→T polymorphism of methylenetetrahydrofolate reductase
Authors: Prinz‐Langenohl R , Brämswig S , Tobolski O , Smulders YM , Smith DEC , Finglas PM , Pietrzik K 
Published: November 2009

Background and purpose:  5,10‐Methylenetetrahydrofolate reductase (MTHFR) is responsible for the synthesis of 5‐methyltetrahydrofolate (5‐MTHF). The 677C→T mutation of MTHFR reduces the activity of this enzyme. The aim of this study was, first, to compare pharmacokinetic parameters of [6S]‐5‐MTHF and folic acid (FA) in women with the homozygous (TT) and wild‐type (CC) 677C→T mutation, and second, to explore genotype differences. The metabolism of [6S]‐5‐MTHF and FA was evaluated by measuring plasma folate derivatives.Experimental approach:  Healthy females (TT, n= 16; CC, n= 8) received a single oral dose of FA (400 µg) and [6S]‐5‐MTHF (416 µg) in a randomized crossover design. Plasma folate was measured up to 8 h after supplementation. Concentration‐time‐profile [area under the curve of the plasma folate concentration vs. time (AUC)], maximum concentration (Cmax) and time‐to‐reach‐maximum (tmax) were calculated.Key results:  AUC and Cmax were significantly higher, and tmax significantly shorter for [6S]‐5‐MTHF compared with FA in both genotypes. A significant difference between the genotypes was observed for tmax after FA only (P < 0.05). Plasma folate consisted essentially of 5‐MTHF irrespective of the folate form given. Unmetabolized FA in plasma occurs regularly following FA supplementation, but rarely with [6S]‐5‐MTHF.Conclusions and implications:  These data suggest that [6S]‐5‐MTHF increases plasma folate more effectively than FA irrespective of the 677C→T mutation of the MTHFR. This natural form of folate could be an alternative to FA supplementation or fortification.
Comparison of the antiepileptogenic effects of an early long‐term treatment with ethosuximide or levetiracetam in a genetic animal model of absence epilepsy
Authors: Russo Emilio , Citraro Rita , Scicchitano Francesca , De Fazio Salvatore , Di Paola Eugenio D. , Constanti Andrew , De Sarro Giovambattista 
Published: November 2009

SummaryPurpose: Epilepsy is a heterogeneous syndrome characterized by recurrent, spontaneous seizures; continuous medication is, therefore, necessary, even after the seizures have long been suppressed with antiepileptic drug (AED) treatments. The most disturbing issue is the inability of AEDs to provide a persistent cure, because these compounds generally suppress the occurrence of epileptic seizures without necessarily having antiepileptogenic properties. The aim of our experiments was to determine, in the WAG/Rij model of absence epilepsy, if early long‐term treatment with some established antiabsence drugs might prevent thedevelopmentof seizures, and whether such an effect could be sustained.Methods: WAG/Rij rats were treated for ∼3.5 months (starting at 1.5 months of age, before seizure onset) with either ethosuximide (ETH; drug of choice for absence epilepsy) or levetiracetam (LEV; a broad‐spectrum AED with antiabsence and antiepileptogenic properties).Results: We have demonstrated that both drugs are able to reduce the development of absence seizures, exhibiting antiepileptogenic effects in this specific animal model.Discussion: These findings suggest that absence epilepsy in this strain of rats very likely follows an epileptogenic process during life and that early therapeutic intervention is possible, thereby opening a new area of research for absence epilepsy and AED treatment strategies.
Meta‐analysis of the association between cysticercosis and epilepsy in Africa
Authors: Quet Fabrice , Guerchet Maëlenn , Pion Sebastien D. S. , Ngoungou Edgard B. , Nicoletti Alessandra , Preux Pierre‐Marie 
Published: November 2009

SummaryPurpose:  The association between cysticercosis and epilepsy has been widely studied in Latin America and Asia and has proven to be one of the main causes of epilepsy. Despite high prevalences of both diseases in Africa, their association remains unclear. In this article we quantified the strength of the association between epilepsy and cysticercosis in Africa and we proposed some guidelines for future studies.Methods:  We performed a systematic review of literature on cysticercosis (considered as exposure) and epilepsy (considered as the disease) and collected data from both cross‐sectional and case–control studies. A common odds ratio was estimated using a random‐effects meta‐analysis model of aggregate published data.Results:  Among 21 retrieved documents, 11 studies located in 8 African countries were included in the meta‐analysis. Odds ratio of developing epilepsy when presenting cysticercosis (defined as Taenia solium seropositivity) ranged from 1.3–6.1. Overall, association between cysticercosis and epilepsy was found significant with a common odds ratio of 3.4 [95% confidence interval (CI) 2.7–4.3; p < 0.001].Discussion:  The variability of the association found between the studies could be due to differences in study design or in pathogenesis of cysticercosis. Further studies should overcome identified problems by following some guidelines to improve epidemiologic and clinical assessment of the association. Better understanding of the relation between cysticercosis and epilepsy is a key issue in improving prevention of epilepsy in Africa.
Dravet syndrome and deep brain stimulation: Seizure control after 10 years of treatment
Authors: Andrade Danielle M. , Hamani Clement , Lozano Andres M. , Wennberg Richard A. 
Published: November 2009

SummaryDravet syndrome is a genetically determined severe epilepsy associated with cognitive decline and ataxia. The many types of seizures seen in these patients are typically pharmacoresistant. Here we describe two adults with Dravet syndrome who were treated with thalamic deep brain stimulation (DBS) and followed for 10 years. One patient with partial onset seizures received DBS at age 19 and showed a marked improvement in seizure control after DBS insertion and stimulation. The other patient with generalized onset seizures received DBS at age 34 and did not show any immediate benefit. No side effects or changes in cognition were observed in either of the patients. This is the first report of (short‐ and) long‐term results in Dravet patients treated with thalamic DBS. We speculate that the results of DBS for epilepsy in patients with Dravet syndrome may be related to age at initiation of DBS treatment and seizure type.
Alveolar bone dimensional changes of post‐extraction sockets in humans: a systematic review
Authors: Van der Weijden Fridus , Dell'Acqua Federico , Slot Dagmar Else 
Published: November 2009

AbstractObjective:To review the literature to assess the amount of change in height and width of the residual ridge after tooth extraction.Material and Methods:MEDLINE‐PubMed and the Cochrane Central register of controlled trials (CENTRAL) were searched through up to March 2009. Appropriate studies which data reported concerning the dimensional changes in alveolar height and width after tooth extraction were included. Approximal height change, mid‐buccal change, mid‐crestal change, mid‐lingual change, Alveolar width change and socket fill were selected as outcome variables. Mean values and if available standard deviations were extracted. Weighted mean changes were calculated.Results:Independent screening of the titles and abstracts of 1244 MEDLINE‐PubMed and 106 Cochrane papers resulted in 12 publications that met the eligibility criteria. The reduction in width of the alveolar ridges was 3.87 mm. The mean clinical mid‐buccal height loss was 1.67 mm. The mean crestal height change as assessed on the radiographs was 1.53 mm. Socket fill in height as measured relative to the original socket floor was on an average 2.57 mm.Conclusion:During the post‐extraction healing period, the weighted mean changes as based on the data derived from the individual selected studies show the clinical loss in width to be greater than the loss in height, assessed both clinically as well as radiographically.
Early healing of implants placed into fresh extraction sockets: an experimental study in the beagle dog. III:soft tissue findings
Authors: Vignoletti Fabio , De Sanctis Massimo , Berglundh Tord , Abrahamsson Ingemar , Sanz Mariano 
Published: November 2009

AbstractAim:To describe histologically the early phases of soft tissue healing to implants placed into fresh extraction sockets.Materials and Methods:In 16 beagle dogs, 64 3.25‐mm‐wide cylindrical screw implants were inserted into the distal sockets of the third and fourth lower premolars using a one‐stage trans‐mucosal healing protocol. Biopsies were then taken at 1, 2, 4 and 8 weeks and prepared for histological examination.Results:One‐week specimens showed a junctional epithelium and an underlying loose connective tissue rich in inflammatory cells. At 2 weeks, signs of epithelial proliferation and a more organized connective tissue were observed. At 4 and 8 weeks, inflammation was absent; the epithelium appeared mature and in close contact with the surface of the healing abutment or the implant. The connective tissue was dense in an area close to the implant surface and the fibres were aligned parallel to the implant surface. The soft tissue dimensions at 8 weeks were approximately 5 mm, including about 3–3.5 mm of epithelium and 1–1.5 mm of connective tissue.Conclusion:Soft tissue healing to implants placed in fresh extraction sockets may result in a longer epithelial interface than implants placed in a healed ridge.
Suitability of radiochromic films for dosimetry of low energy X‐rays
Authors: Ebert Martin A , Asad Ali H , Siddiqui Salim A 
Published: November 2009

This study examined the response characteristics of three commercially available radiochromic films when exposed to low energy (50 kVp) X‐rays. The aim was to evaluate the films for potential use in 2D dosimetry for a low‐kV intraoperative radiotherapy (IORT) device known as the ‘Intrabeam’. Dose‐response relationships were obtained for Gafchromic EBT, XR‐RV2, and XR‐QA film in water at several distances from the Intrabeam device. It was found that the dose rates from the source were excessive for use of the XR‐QA film, and that all three film types showed significant energy dependence within the limits of measurement uncertainty. Basic modeling of primary X‐ray spectra indicated large changes in the lower energy components with distance from the source, and it is hypothesized that the changes in film response are a result of changes in film energy response. This is in contrast to previous studies indicating less or negligible energy response. All films showed non‐linearity in response over the ranges examined. These results imply significant limitations for the use of these films for low‐kV dosimetry.PACS number: 87.53.Bn
Evolution of X‐ray machine quality control acceptance indices
Authors: Ebisawa Maria Lucia Nana I , de Fatima A Magon Maria , Mascarenhas Yvone M 
Published: November 2009

The quality assurance (QA) of radiographic images based on the operating conditions of X‐ray equipment is essential for good image quality, accurate medical diagnostics and for the prevention of health professionals and patients to unnecessary doses of ionizing radiation. This paper presents a historical analysis of 1,635 Quality Assurance Technical Reports of Health Institutions in the state of São Paulo, Brazil, over a seven‐year period. Based on acceptable limits for variations between nominal and measured parameters as the variable to determine the quality of X‐ray equipment operating conditions, a significant improvement was found in the percentage of acceptance of the overall parameters described in the QA technical reports over this period. As expected, we found a strong concentration in the categories of conventional and portable X‐ray equipment, which represent 72% and 84%, respectively, of the total number of equipments. A mechanical parameter such as half‐value layer (HVL), which is important not only for image quality but also for radiation protection, showed significant improvements. Again, only 58% of portable X‐ray equipment showed HVL values recommended for 80 kVp (above 2.3 mm Al), a percentage that improved to 76% in 2006. With regard to mammographers, which are newer machines, all the analyzed systems presented acceptable HVL values. Conventional X‐ray machines showed an increase of this conformity index from 89% in 2000 to 94% in 2006. All this improvement was attributed to the continuous and extensive enforcement of Regulation Act 453 in the state of São Paulo. The improvement in equipment quality control standards is expected to result in the improvement of diagnostic quality, as well as in the reduction of exam repetitions, and thereby reducing the patient's exposure to radiation.PACS number: 87.57.C
Optimization of photon beam energy in aperture‐based inverse planning
Authors: St‐Hilaire Jason , Sévigny Caroline , Beaulieu Frédéric , Gingras Luc , Tremblay Daniel , Beaulieu Luc 
Published: November 2009

Optimal choice of beam energy in radiation therapy is easy in many well‐documented cases, but less obvious in some others. Low‐energy beams may provide better conformity around the target than their high‐energy counterparts due to reduced lateral scatter, but they also contribute to overdosage of peripheral normal tissue. Beam energy was added as an optimization parameter in an automatic aperture‐based inverse planning system. We have investigated a total of six cases for two sites (prostate and lung), representative of deep‐seated and moderately deep‐seated tumors. For one case for each site, different numbers of beam incidences were considered. The other cases for each site were optimized using a fixed number of incidences. Four types of plans were optimized: 6 MV, 23 MV, and mixed energy plans with one or two energies per incidence. Each plan was scored with a dose‐volume cost function. Cost function values, number of segments, monitor units, dose‐volume parameters, and isodose distributions were compared. For the prostate and lung cases, energy mixing improved plans in terms of cost function values, with a more important reduction for a small number of beam incidences. Use of high energy allowed better peripheral tissue sparing, while keeping similar target coverage and sensitive structures avoidance. Low energy contribution to monitor units usually increased with the number of beam incidences. Thus, for deep‐seated and moderately deep‐seated tumors, energy optimization can produce interesting plans with less peripheral dose and monitor units than for low energy alone.PACS numbers: 87.55.de, 87.55.dk, 87.56.N‐
Information technology resource management in radiation oncology*
Authors: Siochi R. Alfredo , Balter Peter , Bloch Charles D. , Bushe Harry S. , Mayo Charles S. , Curran Bruce H. , Feng Wenzheng , Kagadis George C. , Kirby Thomas H. , Stern Robin L. 
Published: November 2009

The ever‐increasing data demands in a radiation oncology (RO) clinic require medical physicists to have a clearer understanding of information technology (IT) resource management issues. Clear lines of collaboration and communication among administrators, medical physicists, IT staff, equipment service engineers, and vendors need to be established. In order to develop a better understanding of the clinical needs and responsibilities of these various groups, an overview of the role of IT in RO is provided. This is followed by a list of IT‐related tasks and a resource map. The skill set and knowledge required to implement these tasks are described for the various RO professionals. Finally, various models for assessing one's IT resource needs are described. The exposition of ideas in this white paper is intended to be broad, in order to raise the level of awareness of the RO community; the details behind these concepts will not be given here and are best left to future task group reports.PACS number: 87.52.Tr, 87.53.St, 87.53.Xd, 87.90.+y
Increasing the Production Accuracy of Profile Bending with Methods of Computational Intelligence
Authors: Selvaggio Alessandro , Dirksen Uwe , Tekkaya A. Erman , Schikorra Marco , Kleiner Matthias 
Published: November 2009

Important quality criteria for profile bending are an accurate profile contour and an accurate cross section. During the bending process, torsion of the profile, deformation of the cross section, and deviations at the profile contour can occur. If these undesired effects are too large, the bent profile is not usable. Critical causes of profile cross section deformation are thin wall thicknesses with hollow sections. The profile torsion is favored by asymmetrical profile cross sections. These effects can be minimized by a production-correct profile design, whereby a trade-off between a production-correct design and the boundary conditions exists. Furthermore, undesired variations in the profile material properties and the profile cross section lead to deviations in the profile contour. These deviations cannot be reduced by design but by usage of a closed-loop control during bending. In this article, a software system for three-roll bending is presented that minimizes undesirable effects during bending by structure optimization of the profile cross section and application of closed-loop control. The structure optimization is based on an evolutionary algorithm and the process control uses a neuro-fuzzy controller. The structure of the software system and results of experiments are presented and discussed. 1
Sense of coherence and psychological outcomes in people with spinal cord injury: Appraisals and behavioural responses
Authors: Kennedy P. , Lude P. , Elfström M. L. , Smithson E. 
Published: November 2009

Study design. Longitudinal, multi‐wave design.Objectives. To investigate the contribution of sense of coherence (SOC), appraisals, and behavioural responses when predicting psychological outcomes to spinal cord injury (SCI).Method. Patients (N =237) sustaining a SCI aged 17 or above were recruited from specialist spinal injuries centres across six European countries. Measures of SOC, appraisals, coping strategies, and psychological well‐being were administered at 6 and 12 weeks post‐injury and at a 1 year follow‐up.Results. People scoring high on SOC at 6 weeks post‐injury showed significantly better psychological outcomes at 1 year post‐injury and SOC showed significant relationships with appraisals at 12 weeks post‐injury and coping strategies 1 year post‐injury. Significant relationships were found between appraisals at 12 weeks post‐injury and psychological outcomes, adaptive coping strategies were significantly related to psychological well‐being at 1 year post‐injury. Regression analyses found SOC, appraisals, and coping behaviours to explain 61.8% of the variance in psychological quality of life, 66.5% of the variance in depression, and 37.7% of the variance in anxiety at 1 year post‐injury.Conclusion. This study provides further evidence in support of previous findings which suggest SOC to have a primary role in long‐term psychological well‐being. The relationship described here – from SOC to the appraisal of injury and subsequent behavioural responses – suggests SOC to be an influential factor in the long‐term adjustment of people with SCI.
Investigating Matrix/Fracture Transfer via a Level Set Method for Drainage and Imbibition
Authors: Prodanovic Maša , Bryant Steven L. , Karpyn Zuleima T. 
Published: November 2009

SummaryMultiphase flow and transport phenomena within fractures are important because fractures often represent primary flow conduits in otherwise low-permeability rock. Flows within the fracture, between the fracture and the adjacent matrix, and through the pore space within the matrix typically happen on different length and time scales. Capturing these scales experimentally is difficult. It is, therefore, useful to have a computational tool that establishes the exact position and shape of fluid/fluid interfaces in realistic fracture geometries. The level set method (LSM) is such a tool. Our progressive quasistatic (PQS) algorithm based on the level set method finds detailed, pore-level fluid configurations satisfying the Young-Laplace equation at a series of prescribed capillary pressures. The fluid volumes, contact areas, and interface curvatures are readily extracted from the configurations. The method automatically handles topological changes of the fluid volumes as capillary pressure varies. It also accommodates arbitrarily complicated shapes of confining solid surfaces.Here, we apply the PQS method to analytically defined fracture faces and aperture distributions, to geometries of fractures obtained from high-resolution images of real rocks, and to idealized fractures connected to a porous matrix. We also explicitly model a fracture filled with proppant, using a cooperative rearrangement algorithm to construct the proppant bed and the surrounding matrix. We focus on interface movement between matrix and fracture, and snap-off of nonwetting phase into the fracture during imbibition in particular. The extent to which nonwetting phase is trapped in fracture/enclosed gaps is very sensitive to the direction of the displacement. Simulated drainage curves in matrix differ systematically from drainage curves in fracture and matrix with transfer between them. In a reservoir simulation, the latter might serve as an upscaled drainage curve input for a fractured medium.