bluuebunny/crossref_metadata_2025_split huggingface dataset:
The extracellular matrix and diffusion barriers in focal cortical dysplasias
Authors: Zamecnik Josef , Homola Ales , Cicanic Michal , Kuncova Klara , Marusic Petr , Krsek Pavel , Sykova Eva , Vargova Lydia 
Published: April 2012

AbstractFocal cortical dysplasias (FCDs) of the brain are recognized as a frequent cause of intractable epilepsy. To contribute to the current understanding of the mechanisms of epileptogenesis in FCD, our study provides evidence that not only cellular alterations and synaptic transmission, but also changed diffusion properties of the extracellular space (ECS), induced by modified extracellular matrix (ECM) composition and astrogliosis, might be involved in the generation or spread of seizures in FCD. The composition of the ECM in FCD and non‐malformed cortex (in 163 samples from 62 patients) was analyzed immunohistochemically and correlated with the corresponding ECS diffusion parameter values determined with the real‐time iontophoretic method in freshly resected cortex (i.e. the ECS volume fraction and the geometrical factor tortuosity, describing the hindrances to diffusion in the ECS). The ECS in FCD was shown to differ from that in non‐malformed cortex, mainly by the increased accumulation of certain ECM molecules (tenascin R, tenascin C, and versican) or by their reduced expression (brevican), and by the presence of an increased number of astrocytic processes. The consequent increase of ECS diffusion barriers observed in both FCD type I and II (and, at the same time, the enlargement of the ECS volume in FCD type II) may alter the diffusion of neuroactive substances through the ECS, which mediates one of the important modes of intercellular communication in the brain – extrasynaptic volume transmission. Thus, the changed ECM composition and altered ECS diffusion properties might represent additional factors contributing to epileptogenicity in FCD.
Laparoscopy in the surgical treatment of rectal cancer in Germany 2000–2009
Authors: Mroczkowski P. , Hac S. , Smith B. , Schmidt U. , Lippert H. , Kube R. 
Published: April 2012

AbstractAim  The goal of this registry study was to compare open surgery with planned laparoscopy and then with laparoscopic to open conversion for rectal cancer surgery.Method  The study included 17 964 rectal cancer patients, operated on between 1 January 2000 and 31 December 2009, from 345 hospitals in Germany. All statistical tests were two‐sided, with the χ2 test (Pearson correlation) for patients and tumour characteristics. Fisher’s exact test was used for complications and 30‐day mortality.Results  Of the 17 964 rectal cancer patients, 16 308 (90.8%) had an open procedure and 1656 (9.2%) were started with a laparoscopy. The 1455 patients with completed laparoscopic operations had fewer intra‐operative and postoperative complications (5.4%vs 7.0%, P = 0.020, and 20.5%vs 25.8%, P < 0.001, respectively) and a lower 30‐day mortality rate (1.1%vs 1.9%, P = 0.023). Of the 1656 planned laparoscopies, 201 (12.1%) were converted to open. The converted group suffered more intra‐operative complications (18.9%vs 3.6% for completed laparoscopy and 7.0% for open surgery, P < 0.0001) and postoperative complications (32.3%vs 18.9% for completed laparoscopy and 25.8% for open operations, P < 0.0001). The converted group also had a higher 30‐day mortality rate (2.0%vs 1.0% for completed laparoscopy and 1.9% for open surgery, P = 0.043).Conclusion  The more favourable patient profile provided justification for a laparoscopic procedure. For those converted to an open procedure, however, there were significantly more complications than planned open surgery patients. A move away from the standard open procedure for rectal cancer surgery and towards laparoscopy is not yet feasible.
Using webcasts in education: Evaluation of its effectiveness
Authors: Giannakos Michail N. , Vlamos Panayiotis 
Published: April 2012

AbstractEducational webcasts are nowadays widely used by many organizations and institutions all over the world. However, the educational effectiveness of webcasts when used as an autonomous method is yet to be explored. In this paper, the clarification of certain issues concerning their educational effectiveness is attempted. Following specific instructions, an educational webcast was developed, and then a between group evaluation experiment was conducted. The experiment compared traditional learning and an educational webcast. A total of 66 gymnasium (middle school) students were placed in two groups based on a pretest method. The results of the evaluation showed that educational webcasts can be very effective on certain conditions. On the one hand, the educational effectiveness of the webcast was particularly high when applied to tasks that required simple comprehension. On the other hand, the webcast had poor performance in the consolidation of complex tasks.Practitioner NotesWhat is already known about this topic
Advocates of webcasting in education indicate that these technologies can improve student performance; they mention that webcasting lectures in their entirety are useful for revision, reviewing purposes and assist students to fill in learning gaps.
Webcasts provide students the opportunity to actively engage with the material by allowing learners to directly and repeatedly access a specific section of presentations and/or control the speed to play the media file.
Prior studies (eg, McKinney, Dyck & Luber, 2009; Traphagan, Kucsera & Kishi, 2010) also found that students who reported using lecture webcasts as a replacement for the in‐class lecture exhibited lower performance.
What this paper adds
We focus on the effectiveness of webcast as an autonomous learning tool and find that in some cases, webcast's performance can reach traditional learning performance.
This research found that in simple comprehension tasks, webcasts seem to have much better performance compared with traditional learning.
Findings indicate that in tasks where a greater degree of comprehension is required, webcast and traditional learning seem to have the same performance.
This research found that in complex tasks that required additional comprehension and a great degree of consolidation, webcasts had very low performance and few of the students coped with the complex task.
Implications for practice and/or policy
Asynchronous‐autonomous teaching with webcasts may demonstrate good performance.
Webcast is more efficient when it comes to light‐epidermal tasks (eg, multiple choice questions).
For knowledge that has to be comprehended and consolidated, in order to be used in combination with other knowledge for solving complex tasks, the webcast is not recommended because its performance in this area is very poor.
Voting for Redistribution under Desert‐Sensitive Altruism*
Authors: Luttens Roland Iwan , Valfort Marie‐Anne 
Published: April 2012

AbstractWe endow individuals who differ in skills and tastes for working, with altruistic preferences for redistribution in a voting model where a unidimensional redistributive parameter is chosen by majority voting in a direct democracy. When altruistic preferences are desert‐sensitive (i.e., when there is a reluctance to redistribute from the hard‐working to the lazy), we show that lower levels of redistribution emerge in political equilibrium. We provide empirical evidence that preferences for redistribution are not purely selfish, and that desert‐sensitive motivations play a significant role. We estimate that preferences for redistribution are significantly more desert‐sensitive in the US than in Europe.
Fabry disease in unselected patients with TIA or stroke: population‐based study
Authors: Marquardt L. , Baker R. , Segal H. , Burgess A. I. , Poole D. , Hughes D. A. , Rothwell P. M. 
Published: April 2012

BackgroundFabry disease (FD) is an X‐linked lysosomal storage disorder frequently associated with cerebrovascular disease. In recent years, the prevalence of FD has been reported to be up to 4% in cryptogenic young stroke patients. However, there have been no population‐based studies in unselected patients with transient ischaemic attack (TIA) or stroke across the full range of ages.MethodsWe determined the prevalence of FD mutations in consecutive patients from a population‐based study of acute TIA or ischaemic stroke (Oxford Vascular Study). Analysis included amplifying of the α‐galactosidase A gene by polymerase chain reaction, denaturing high‐performance liquid chromatography (dHPLC) analysis and sequencing using standard automated sequencing protocols [Mutation Surveyor software (Softgenetics)] where the dHPLC indicated a possible mutation.ResultsSamples of 1046 consecutive patients (52% women; mean age 73.2 years; 15% age <60 years; 572 stroke; 474 TIA) were tested. No patient had a known gene mutation causing FD, giving an upper 95% confidence interval around the estimated frequency of 0.35% overall and 2.37% in the 154 patients aged under 60 years. However, in 5 (0.48%) samples, a known polymorphism or sequence variation in the gene was identified that can be associated with lower than normal enzyme activity in plasma without causing the full clinical manifestation of FD.ConclusionsFabry disease is rare in an unselected group of UK patients with TIA or stroke. Larger studies in unselected younger patients with cryptogenic stroke are required to determine whether routine screening is justified in this group.
Forced Migration, Climate Change, Mitigation and Adaptive Policies in Mexico: Some Functional Relationships
Authors: Cohen Ignacio Sánchez , Spring Úrsula Oswald , Padilla Gabriel Díaz , Paredes Julian Cerano , Inzunza Ibarra Marco A. , López Rutilo López , Díaz José Villanueva 
Published: April 2012

AbstractNatural disasters related to hydro‐meteorological events have increased during the last few decades, both in frequency and severity. Mexico is heavily exposed to climate change, but has also suffered in the past from climate variability (Blümel, 2009). The new risks oblige the government to develop mitigation processes, while the affected people are implementing strategies of adaptation and resilience‐building, mostly at the family and community level. This includes forced migration due to climate change into the slums of megacities or illegal immigration to the United States. The arid, semi‐arid and subhumid condition of 49.2 per cent of the territory of Mexico is seriously affected by climate change. In addition, poverty and the lack of jobs have created complex livelihood situations, in which young people leave rural areas, partly due to socio‐economic pull factors. In this paper, we address the functional relationships between climate patterns and migration processes in Mexico, highlighting the linkages between the origin of migrants, their economic activity and their vulnerability to extreme events and we discuss long‐term climate patterns. Agriculture still uses 78 per cent of the available water in Mexico. In the drylands the competition for water use requires an integrated policy to deal with the new threats from climate change, including mitigation from the top down and adaptation processes from the bottom up to reduce the social vulnerability of the rural population in the highly affected drylands of the central and northern parts of Mexico. The new policy for administering water resources, which promotes the efficient use of an increasingly scarce and polluted resource, still suffers from a lack of participation by the affected rural population. In this paper, we propose an integrated management system from the watershed onwards, involving socio‐economic, political, cultural and hydrological variables, to deal with the rising scarcity of water, and the uncertainty and complexity of climate change.
Repetition of self‐harm and suicide following self‐harm in children and adolescents: findings from the Multicentre Study of Self‐harm in England
Authors: Hawton Keith , Bergen Helen , Kapur Navneet , Cooper Jayne , Steeg Sarah , Ness Jennifer , Waters Keith 
Published: April 2012

Background:  Self‐harm (intentional self‐poisoning and self‐injury) in children and adolescents is often repeated and is associated with increased risk of future suicide. We have investigated factors associated with these outcomes.Method:  We used data collected in the Multicentre Study of Self‐harm in England on all self‐harm hospital presentations by individuals aged 10–18 years between 2000 and 2007, and national death information on these individuals to the end of 2010. Cox hazard proportional models were used to identify independent and multivariable predictors of repetition of self‐harm and of suicide.Results:  Repetition of self‐harm occurred in 27.3% of individuals (N = 3920) who presented between 2000 and 2005 and were followed up until 2007. Multivariate analysis showed that repetition was associated with age, self‐cutting, and previous self‐harm and psychiatric treatment. Of 51 deaths in individuals who presented between 2000 and 2007 and were followed up to 2010 (N = 5133) half (49.0%) were suicides. The method used was usually different to that used for self‐harm. Multivariate analysis showed that suicide was associated with male gender [Hazard ratio (HR) = 2.4, 95% CI 1.2–4.8], self‐cutting (HR = 2.1, 95% CI 1.1–3.7) and prior psychiatric treatment at initial presentation (HR = 4.2, 95% CI 1.7–10.5). It was also associated with self‐cutting and history of psychiatric treatment at the last episode before death, and history of previous self harm.Conclusions:  Self‐cutting as a method of self‐harm in children and adolescents conveys greater risk of suicide (and repetition) than self‐poisoning although different methods are usually used for suicide. The findings underline the need for psychosocial assessment in all cases.
Mechanism and molecular basis for the sodium channel subtype specificity of µ‐conopeptide CnIIIC
Authors: Markgraf René , Leipold Enrico , Schirmeyer Jana , Paolini‐Bertrand Marianne , Hartley Oliver , Heinemann Stefan H 
Published: April 2012

BACKGROUND AND PURPOSE Voltage‐gated sodium channels (NaV channels) are key players in the generation and propagation of action potentials, and selective blockade of these channels is a promising strategy for clinically useful suppression of electrical activity. The conotoxin µ‐CnIIIC from the cone snail Conus consors exhibits myorelaxing activity in rodents through specific blockade of skeletal muscle (NaV1.4) NaV channels.EXPERIMENTAL APPROACH We investigated the activity of µ‐CnIIIC on human NaV channels and characterized its inhibitory mechanism, as well as the molecular basis, for its channel specificity.KEY RESULTS Similar to rat paralogs, human NaV1.4 and NaV1.2 were potently blocked by µ‐CnIIIC, the sensitivity of NaV1.7 was intermediate, and NaV1.5 and NaV1.8 were insensitive. Half‐channel chimeras revealed that determinants for the insensitivity of NaV1.8 must reside in both the first and second halves of the channel, while those for NaV1.5 are restricted to domains I and II. Furthermore, domain I pore loop affected the total block and therefore harbours the major determinants for the subtype specificity. Domain II pore loop only affected the kinetics of toxin binding and dissociation. Blockade by µ‐CnIIIC of NaV1.4 was virtually irreversible but left a residual current of about 5%, reflecting a ‘leaky’ block; therefore, Na+ ions still passed through µ‐CnIIIC‐occupied NaV1.4 to some extent. TTX was excluded from this binding site but was trapped inside the pore by µ‐CnIIIC.CONCLUSION AND IMPLICATIONS Of clinical significance, µ‐CnIIIC is a potent and persistent blocker of human skeletal muscle NaV1.4 that does not affect activity of cardiac NaV1.5.
Blockade of adipocyte differentiation by cordycepin
Authors: Takahashi Shuhei , Tamai Minori , Nakajima Shotaro , Kato Hironori , Johno Hisashi , Nakamura Tomoyuki , Kitamura Masanori 
Published: April 2012

BACKGROUND AND PURPOSE Cordyceps militaris has the potential to suppress differentiation of pre‐adipocytes. However, the active entities in the extract and the underlying mechanisms of its action are not known. Hence, we investigated whether and how cordycepin (3′‐deoxyadenosine), a constituent of C. militaris, inhibits adipogenesis.EXPERIMENTAL APPROACH Differentiation of 3T3‐L1 pre‐adipocytes and pre‐adipocytes in primary cultures was induced by Insulin, dexamethasone and IBMX, and these were used as in vitro models of adipogenesis. The effects of cordycepin on adipogenesis were examined with particular focus on the regulation of CCAAT/enhancer‐binding protein β (C/EBPβ) and PPARγ.KEY RESULTS Cordycepin suppressed the lipid accumulation and induction of adipogenic markers that occurred on differentiation of pre‐adipocytes and also blocked the down‐regulation of a pre‐adipocyte marker. This anti‐adipogenic effect was reversible and mediated by an adenosine transporter, but not A1, A2 or A3 adenosine receptors. This effect of cordycepin was not reproduced by other adenosine‐related substances, including ATP, ADP and adenosine. Early induction of the adipogenic C/EBPβ–PPARγ pathway was suppressed by cordycepin. Blockade of mTORC1 via inhibition of PKB (Akt) and activation of AMP kinase was identified as the crucial upstream event targeted by cordycepin. In addition to its negative effect on adipogenesis, cordycepin suppressed lipid accumulation in mature adipocytes.CONCLUSIONS AND IMPLICATIONS These results suggest that the anti‐adipogenic effects of cordycepin occur through its intervention in the mTORC1‐C/EBPβ–PPARγ pathway. Cordycepin, by blocking both adipogenesis and lipid accumulation, may have potential as a therapeutic agent for effective treatment of obesity and obesity‐related disorders.
Effects of milnacipran, a 5‐HT and noradrenaline reuptake inhibitor, on C‐fibre‐evoked field potentials in spinal long‐term potentiation and neuropathic pain
Authors: Ohnami S , Kato A , Ogawa K , Shinohara S , Ono H , Tanabe M 
Published: April 2012

BACKGROUND AND PURPOSE The analgesic action of 5‐HT and noradrenaline reuptake inhibitors (SNRIs) on nociceptive synaptic transmission in the spinal cord is poorly understood. We investigated the effects of milnacipran, an SNRI, on C‐fibre‐evoked field potentials (FPs) in spinal long‐term potentiation (LTP), a proposed synaptic mechanism of hypersensitivity, and on the FPs in a neuropathic pain model.EXPERIMENTAL APPROACH C‐fibre‐evoked FPs by electrical stimulation of the sciatic nerve fibres were recorded in the spinal dorsal horn of anaesthetized adult rats, and LTP was induced by high‐frequency stimulation of the sciatic nerve fibres. A rat model of neuropathic pain was produced by L5 spinal nerve ligation and transection.KEY RESULTS Milnacipran produced prolonged inhibition of C‐fibre‐evoked FPs when applied spinally after the establishment of LTP of C‐fibre‐evoked FPs in naïve animals. In the neuropathic pain model, spinal administration of milnacipran clearly reduced the basal C‐fibre‐evoked FPs. These inhibitory effects of milnacipran were blocked by spinal administration of methysergide, a 5‐HT1/2 receptor antagonist, and yohimbine or idazoxan, α2‐adrenoceptor antagonists. However, spinal administration of milnacipran in naïve animals did not affect the basal C‐fibre‐evoked FPs and the induction of spinal LTP.CONCLUSION AND IMPLICATIONS Milnacipran inhibited C‐fibre‐mediated nociceptive synaptic transmission in the spinal dorsal horn after the establishment of spinal LTP and in the neuropathic pain model, by activating both spinal 5‐hydroxytryptaminergic and noradrenergic systems. The condition‐dependent inhibition of the C‐fibre‐mediated transmission by milnacipran could provide novel evidence regarding the analgesic mechanisms of SNRIs in chronic pain.
Peripheral blood stem cell transplant–related Plasmodium falciparum infection in a patient with sickle cell disease
Authors: Mejia Rojelio , Booth Garrett S. , Fedorko Daniel P. , Hsieh Matthew M. , Khuu Hanh M. , Klein Harvey G. , Mu Jianbing , Fahle Gary , Nutman Thomas B. , Su Xin‐Zhuan , Williams Esther C. , Flegel Willy A. , Klion Amy 
Published: April 2012

BACKGROUND: Although transmission of Plasmodium falciparum (Pf) infection during red blood cell (RBC) transfusion from an infected donor has been well documented, malaria parasites are not known to infect hematopoietic stem cells. We report a case of Pf infection in a patient 11 days after peripheral blood stem cell transplant for sickle cell disease.STUDY DESIGN AND METHODS: Malaria parasites were detected in thick blood smears by Giemsa staining. Pf HRP2 antigen was measured by enzyme‐linked immunosorbent assay on whole blood and plasma. Pf DNA was detected in whole blood and stem cell retention samples by real‐time polymerase chain reaction using Pf species–specific primers and probes. Genotyping of eight Pf microsatellites was performed on genomic DNA extracted from whole blood.RESULTS: Pf was not detected by molecular, serologic, or parasitologic means in samples from the recipient until Day 11 posttransplant, coincident with the onset of symptoms. In contrast, Pf antigen was retrospectively detected in stored plasma collected 3 months before transplant from the asymptomatic donor. Pf DNA was detected in whole blood from both the donor and the recipient after transplant, and genotyping confirmed shared markers between donor and recipient Pf strains. Lookback analysis of RBC donors was negative for Pf infection.CONCLUSIONS: These findings are consistent with transmission by the stem cell product and have profound implications with respect to the screening of potential stem cell donors and recipients from malaria‐endemic regions.
Effects of Sheath Injury and Trimetazidine on Endothelial Dysfunction of Radial Artery after Transradial Catheterization
Authors: PARK KYOUNG‐HA , PARK DUK‐WOO , KIM MIN‐KYU , KIM HYUN‐SOOK , PARK WOO JUNG , CHO GOO‐YEONG , CHOI YOUNG‐JIN 
Published: April 2012

Objective:

We evaluated the effects of sheath injury and trimetazidine (TMZ) on endothelial dysfunction of the radial artery (RA) after transradial coronary artery angiography (TRCAG) or transradial percutaneous coronary intervention (TRPCI) with flow‐mediated dilation (FMD).
Methods:

One hundred twenty patients who underwent TRCAG or TRPCI with either a long 5Fr or 6Fr sheath were randomly assigned to the TMZ group or the control group. Baseline, postsheath injury (<24 hours after sheath injury), and 10‐week FMDs were performed.
Results:

In all cannulated RAs, the postsheath injury FMDs were significantly lower than the baseline FMDs (P < 0.01). In the control group, the 10‐week FMD was significantly lower than the baseline FMD, but no difference was found in the TMZ group (10.4 ± 3.4% vs. 6.3 ± 2.9%, P < 0.01 and 10.1 ± 3.6% vs. 9.2 ± 3.6%, P = 0.09, respectively). Repeated measures ANOVA revealed significant differences in FMD between the TMZ group and the control group (F = 9.87, P < 0.01). Including coronary artery disease, heparin dose during procedure, sheath size, sheath‐RA size ratio, sheath indwelling time in RA, RA spasm, repeated RA sheath injury (upsizing from 5Fr to 6Fr), and TMZ use, the multivariate analysis showed that repeated RA sheath injury and TMZ use (OR 7.40, 95% CI 1.42–38.53, P < 0.05, and OR 0.08, 95% CI 0.02–0.30, P < 0.01, respectively) were independent predictors of the decrement of FMD > 50% (ΔFMDbaseline – 10 week > 50%).
Conclusion:

Repeated sheath injury negatively influences endothelial recovery after long 6Fr sheath injury to the RA, and TMZ lessens endothelial dysfunction of the RA after radial catheterization. (J Interven Cardiol 2012;25:411–417)