bluuebunny/crossref_metadata_2025_split huggingface dataset:
Blood vessels of the normal and pathologically changed wall of the human vena saphena magna
Authors: Kachlik David , Baca Vaclav , Fara Petr , Lametschwandtner Alois , Minnich Bernd , Musil Vladimir , Sosna Bohuslav , Stingl Josef , Straka Zdenek , Setina Marek 
Published: July 2008

Abstract
The vascular supply of the wall of human vena saphena magna was qualitatively studied by the use of several morphological methods on both normal and pathologically changed veins. The material was obtained from patients undergoing aortocoronary bypass or surgery of the varices, and material from cadavers. Under physiological conditions, the wall of vena saphena magna is supplied by delicate system of vasa vasorum, organized in a form of feeding vessels branched into an irregular loose adventitial mesh and continuing further as a microcirculatory network supplying the two outer thirds of the media. Small local dilatations and tortuosities of adventitial veins were found on heavy varicose veins. Slight increase of vasa vasorum growing into the innermost layer of media was detected, but the hyperplastic intima remained avascular. In patients with recurrent varices or with vein thrombophlebitis intimal hyperplasia, degradation of media and thrombosis, were found. Apparent massive increase of vasa vasorum growing into the whole media, hyperplastic intima and into the organizing thrombi, were regularly observed. The increase of vasa vasorum is a part of the complex of pathophysiological reactions of the vein wall on the hypoxia developing during the most serious pathological changes, and not as the primary varicogenic factor. The vascular supply of the wall of the human vena saphena magna was qualitatively studied by the use of several morphological methods on both normal and pathologically changed veins. The material was obtained from patients undergoing aortocoronary bypass grafting or surgery of varices, as well as materials from cadavers. Under physiological conditions the wall of vena saphena magna is supplied by a delicate system of vasa vasorum. It is organized in a form of feeding vessels branched into an irregular loose adventitial mesh, which continues further as a microcirculatory network supplying the outer two thirds of the media. Small local dilatations and tortuosities of adventitial veins were found on severe varicose veins. A slight increase of the vasa vasorum growing into the innermost layer of media was detected, but the hyperplastic intima remained avascular. In patients with recurrent varices or vein thrombophlebitis, intimal hyperplasia, degradation of media and thrombosis, were found. It was regularly observed that there was an apparent, massive increase of the vasa vasorum growing into the entire media, hyperplastic intima, and into the organizing thrombi. The increase of the vasa vasorum is due to the pathophysiological reaction of the vein wall as a result of hypoxia, which develops during the most serious pathological changes. The increase is not the primary varicogenic factor.
Prognostic value of mean platelet volume in patients with upper gastrointestinal bleeding
Authors: Nalbant Selim , Cagiltay Eylem , Terekeci Hakan , Kaplan Mustafa , Sahan Burak , Sayan Ozkan , Oktenli Cagatay 
Published: July 2008

Abstract
This study included patients with upper gastrointestinal hemorrhage who were treated in intensive care unit of GATA Haydarpasa Training Hospital, Division of Internal Medicine during 1 year. Medical and demographic data of the patients were recorded. These patients were followed for 3 months after being discharged from the intensive care unit. Of the 50 patients in the study, 18 were female (36%), 32 were male (64%). The mean age was 47±2 years, and the ages ranged between 17 and 89 years. We did not find any statistically significant results in our evaluation of the relationship between the mean platelet volume and the number of transfusions, endoscopic findings, and prognosis after 3 months of follow-up.
The effect of calnexin deletion on the expression level of binding protein (BiP) under heat stress conditions in Saccharomyces cerevisiae
Authors: Zhang Huili , Hu Bingjie , Ji Yanyan , Kato Akio , Song Youtao 
Published: July 2008

AbstractIn order to investigate the effect of calnexin deletion on the induction of the main ER molecular chaperone BiP, we cultured the wild-type and calnexin-disrupted Saccharomyces cerevisiae strains under normal and stressed conditions. The growth rate of the calnexin-disrupted yeast was almost the same as that of the wild-type yeast under those conditions. However, the induced level of BiP mRNA in the ER was evidently higher in calnexin-disrupted S. cerevisiae than in the wild-type at 37°C, but was almost the same in the two strains under normal conditions. The Western blot analysis results for BiP protein expression in the ER showed a parallel in the mRNA levels in the two strains. It is suggested that under heat stress conditions, the induction of BiP in the ER might recover part of the function of calnexin in calnexin-disrupted yeast, and result in the same growth rate as in wild-type yeast.
Gene trapping: An antibody-dependent approach for verifying integration in your favorite gene
Authors: Gorelik Anna , Sapir Tamar , Reiner Orly 
Published: July 2008

AbstractGene trapping is used to introduce genome-wide insertional mutations in embryonic stem cells. Determining the integration site is based on highthroughput PCR, which has inevitable possibilities for mistakes, thus necessitating clone verification prior to the generation of mutant mice. Here, we propose a rapid method to validate gene identity based on the fact that many high throughput gene-trapping integrations result in fusion proteins encompassing the N-terminal portion of the gene of interest and LacZ being expressed in embryonic stem cells. Our method utilizes an immunoprecipitation assay using a specific N-terminal-directed antibody to the protein product of the gene of interest followed by a color LacZ assay of the immunoprecipitate, strongly supporting the formation of a fusion protein when the color develops.
Spectral and orientational properties of new group of naphthalene derivatives of bicarboxylic acid in liquid crystal 7CB
Authors: Bielejewska N. , Wolarz E. , Stolarski R. , Bauman D. 
Published: July 2008

AbstractThe spectral and orientational properties of some dichroic fluorescent dyes (naphthalene derivatives of bicarboxylic acid) in some isotropic solvents and in an anisotropic matrix have been studied. The order parameter of the dyes in the nematogenic liquid crystal 7CB has been determined from measurements of polarized electronic absorption and fluorescence. The influence of the dye addition on the nematic-isotropic phase transition temperature of 7CB has been investigated. It was found that some of the dyes studied could be successfully utilized in guest-host liquid crystal display devices.
Comparison of dielectric and optical responses of chevron ferroelectric liquid crystals
Authors: Jeżwski W. , Kuczyński W. , Hoffmann J. , Dardas D. 
Published: July 2008

AbstractAn analysis of consistency of dielectric and optical response methods is carried out for surface stabilized ferroelectric liquid crystals (SSFLC) with chevron geometry. The consistency is found both theoretically and experimentally for weak external electric fields of intermediate frequencies, for which the response of SSFLC is dominated by collective relaxation processes due to azimuthal reorientation of molecules arranging chevron layers. The methods are experimentally shown to lack consistency within very low, relatively low, and high field-frequency ranges. The disagreement appearing at relatively low frequencies is argued to be a consequence of different recording by dielectric and optical techniques the dynamics of zig-zag walls, forming defects in chevron structure.
Flexoelectric effect modelling
Authors: Kapanowski A. 
Published: July 2008

AbstractA statistical theory of dipole flexoelectric (FE) polarization in liquid crystals is used to calculate temperature dependence of order parameters, elastic constants and FE coefficients. Two systems with polar wedge-shaped and banana-shaped molecules are investigated. In both cases, the FE coefficients are proportional to the dipole moment component parallel to the molecule symmetry axis. It results from the symmetries of interactions and of the Mayer function. The origin of the FE effect and microscopic pictures of the distorted phases are discussed.
Polarization difference image analysis with LC filter
Authors: Sutkowski M. , Garbat P. , Nowinowski-Kruszelnicki E. , Walczak A. , Parka J. , Woźnicki J. 
Published: July 2008

AbstractImage analysis using polarizing methods allows removing the polarized light component from recorded images. This is known as polarization difference imaging (PDI). The use of liquid crystals (LC) in PDI was proposed in 2002. Modified LC unit with a properly oriented LC layer was proposed by the authors. The main parameters which characterize an imaging system, employing a circular LC filter, were determined and presented in previous papers.In this work, the basics of the circular LC filter construction and theory are presented. Two application configurations of PDI imaging systems are shown. Experimental results of image processing based on object’s polarization properties are discussed.
Growth rates of intracranial aneurysms: exploring constancy
Authors: Koffijberg Hendrik , Buskens Erik , Algra Ale , Wermer Marieke J. H. , Rinkel Gabriel J. E. 
Published: July 2008

Object
The annual rate of rupture of intracranial aneurysms is often assumed to be constant, but it is unknown whether this assumption is true. Recent case reports have suggested that aneurysms grow fast in a short period of time. The authors of the present report investigated the plausibility of a constant growth rate for intracranial aneurysms.

Methods
Assuming a constant aneurysm growth rate within an individual and varying rates between individuals, a hypothetical cohort was simulated. Individuals with high growth rates will display aneurysm formation and rupture at a young age; such persons disappear early from the hypothetical cohort. As a result the mean lesion growth rate varies over time. In hypothetical cohorts with different initial mean growth rates, the authors calculated age-specific incidence rates (per 100,000 person-years) of subarachnoid hemorrhage and compared these rates with population-based data on the incidence of subarachnoid hemorrhage (per 100,000 person-years).

Results
A hypothetical cohort with a mean initial growth rate of 0.18 mm/year reproduced most closely the incidence rates observed in the population. However, even for this most plausible hypothetical cohort, age-specific incidence rates in the model differed substantially and statistically significantly from those observed in the population.

Conclusions
Based on the results of this study, it is unlikely that intracranial aneurysms in general grow at a constant time-independent rate. The authors hypothesized that the actual growth process is irregular and discontinuous, which results in periods with and without aneurysm growth and with high and low risks of rupture.
Hydrogel coil–related delayed hydrocephalus in patients with unruptured aneurysms
Authors: Marchan Edward M. , Sekula Raymond F. , Ku Andrew , Williams Robert , O'Neill Brent R. , Wilberger Jack E. , Quigley Matthew R. 
Published: July 2008

Object
Because of high recanalization rates associated with wide-necked intracranial aneurysms treated with bare platinum coils, hydrogel coils (HydroCoil, MicroVention, Inc.) have been developed. Hydrogel coils undergo progressive expansion once exposed to the physiological environment of blood and increase overall aneurysm filling.

Methods
The authors retrospectively reviewed their series of patients with unruptured aneurysms treated between 1998 and 2006 and who underwent placement of bare platinum and hydrogel coils for cerebral aneurysms. They examined the incidence of delayed hydrocephalus as related to coil type. In a subgroup of patients in which preand postprocedure CT and MR imaging studies were available, the authors quantitatively analyzed the ventricular size change after hydrogel coils were placed.

Results
Four of 29 patients treated with hydrogel coils developed symptomatic hydrocephalus 2–6 months after the intervention compared with 0 of 26 treated with bare platinum coils alone. The difference in ventricular size between the subgroups in which pre- and postprocedure imaging was performed was found to be statistically significant (p < 0.05). All 4 HydroCoil-treated patients in whom hydrocephalus developed required placement of a shunt.

Conclusions
A 14% incidence (95% confidence interval 3.9–31.7%) of hydrocephalus in patients with unruptured aneurysm undergoing embolization with hydrogel coils was discovered. This incidence is much higher than previously reported. The mechanism by which hydrogel coils may induce hydrocephalus remains poorly understood.
Cranial nerve palsy following transvenous embolization for a cavernous sinus dural arteriovenous fistula: association with the volume and location of detachable coils
Authors: Nishino Kazuhiko , Ito Yasushi , Hasegawa Hitoshi , Kikuchi Bumpei , Shimbo Junsuke , Kitazawa Keiko , Fujii Yukihiko 
Published: July 2008

Object
Transvenous embolization (TVE) for the treatment of a cavernous sinus (CS) dural arteriovenous fistula (DAVF) occasionally causes cranial nerve palsy (CNP). Overpacking of coils is considered to result in CNP. The purpose of this study was to analyze the association of TVE-induced CNP with the volume and location of coils activated in the CS.

Methods
Thirty-one patients with CS DAVFs (33 lesions) underwent TVE.

Results
Cranial nerve palsy occurred or was aggravated in 13 cases (39.4%; CNP group). The cumulative volume of activated coils was significantly greater in the CNP group (0.241 ± 0.172 cm3) than in the non-CNP group (0.119 ± 0.075 cm3; p < 0.05). Of those lesions with > 0.2 cm3 of coil volume, 77.8% showed immediate aggravation or a new occurrence of CNP after TVE. Five lesions treated with a smaller volume of coils showed a delayed worsening or occurrence of CNP. In cases with induced oculomotor nerve palsy, coils had been densely packed in the superolateral part of the anterior CS. Dense packing in the lateral portion of the posterior CS frequently induced abducent nerve palsy. Although patients harboring lesions with a greater coil volume required a longer recovery time, newly developed or aggravated CNP, related to 84.6% of the lesions, resolved completely.

Conclusions
The cumulative volume and specific locations of coils in the CS correlated with TVE-induced CNP. Overpacking appeared to be the predominant cause of CNP; however, for CNP in cases involving smaller coil volumes, an alternative mechanism may be involved.
Efficacy and safety of a collagen matrix for cranial and spinal dural reconstruction using different fixation techniques
Authors: Stendel Ruediger , Danne Marco , Fiss Ingo , Klein Ilse , Schilling Andreas , Hammersen Stefanie , Pietilae Terttu , Jänisch Werner , Hopfenmüller Werner 
Published: July 2008

Object
The use of dural grafts is frequently unavoidable when tension-free dural closure cannot be achieved following neurosurgical procedures or trauma. Biodegradable collagen matrices serve as a scaffold for the regrowth of natural tissue and require no suturing. The aim of this study was to investigate the efficacy and safety of dural repair with a collagen matrix using different fixation techniques.

Methods
A total of 221 patients (98 male and 123 female; mean age 55.6 ± 17.8 years) undergoing cranial (86.4%) or spinal (13.6%) procedures with the use of a collagen matrix dural graft were included in this retrospective study. The indications for use, fixation techniques, and associated complications were recorded.

Results
There were no complications of the dural graft in spinal use. Five (2.6%) of 191 patients undergoing cranial procedures developed infections, 3 of which (1.6%) were deep infections requiring surgical revision. There was no statistically significant relationship between the operative field status before surgery and the occurrence of a postoperative wound infection (p = 0.684). In the 191 patients undergoing a cranial procedure, cerebrospinal fluid (CSF) collection occurred in 5 patients (2.6%) and a CSF fistula in 5 (2.6%), 3 of whom (1.6%) required surgical revision. No patient who underwent an operation with preexisting CSF leakage had postoperative CSF leakage. Postoperative infection significantly increased the risk for postoperative CSF leakage.
The collagen matrix was used without additional fixation in 124 patients (56.1%), with single fixation in 55 (24.9%), and with multiple fixations in 42 (19%). There were no systemic allergic reactions or local skin changes. Follow-up imaging in 112 patients (50.7%) revealed no evidence of any adverse reaction to the collagen graft.

Conclusions
The collagen matrix is an effective and safe cranial and spinal dural substitute that can be used even in cases of an existing local infection. Postoperative deep infection increases the risk for CSF leakage.
Preoperative localization of hand motor cortex by adaptive spatial filtering of magnetoencephalography data
Authors: Nagarajan Srikantan , Kirsch Heidi , Lin Peter , Findlay Anne , Honma Susanne , Berger Mitchel S. 
Published: July 2008

Object
The goal of this study was to examine the sensitivity and specificity in preoperative localization of hand motor cortex by imaging regional event-related desynchronization (ERD) of brainwaves in the β frequency band (15–25 Hz) involved in self-paced movement.

Methods
Using magnetoencephalography (MEG), the authors measured ERD that occurred before self-paced unilateral index finger flexion in 66 patients with brain tumors, epilepsy, and arteriovenous malformations.

Results
The authors applied an adaptive spatial filtering algorithm to MEG data and found that peaks of the tomographic distribution of β-band ERD sources reliably localized hand motor cortex compared with electrical cortical stimulation. They also observed high specificity in estimating contralateral hand motor cortical representations relative to somatosensory cortex. Neither presence nor location of tumor changed the qualitative or quantitative location of motor cortex relative to somatosensory cortex.

Conclusions
An imaging protocol using ERD obtained by adaptive spatial filtering of MEG data can be used for extremely reliable preoperative localization of hand motor cortex.
Subthalamic deep brain stimulation after anesthetic inhalation in Parkinson disease: a preliminary study
Authors: Lin Sheng-Huang , Chen Tsung-Ying , Lin Shinn-Zong , Shyr Ming-Hwang , Chou Yu-Cheng , Hsieh Wanhua Annie , Tsai Sheng-Tzung , Chen Shin-Yuan 
Published: July 2008

Object
The authors of this preliminary study investigated the outcome and feasibility of intraoperative microelectrode recording (MER) in patients with Parkinson disease (PD) undergoing deep brain stimulation of the subthalamic nucleus (STN) after anesthetic inhalation.

Methods
The authors conducted a retrospective analysis of 10 patients with PD who received a desflurane anesthetic during bilateral STN electrode implantation. The MERs were obtained as an intraoperative guide for final electrode implantation and the data were analyzed offline. The functional target coordinates of the electrodes were compared preoperatively with estimated target coordinates.

Results
Outcomes were evaluated using the Unified Parkinson's Disease Rating Scale 6 months after surgery. The mean improvement in total and motor Unified Parkinson's Disease Rating Scale scores was 54.27 ± 17.96% and 48.85 ± 16.97%, respectively. The mean STN neuronal firing rate was 29.7 ± 14.6 Hz. Typical neuronal firing patterns of the STN and substantia pars nigra reticulata were observed in each patient during surgery. Comparing the functional target coordinates, the z axis coordinates were noted to be significantly different between the pre- and postoperative coordinates.

Conclusions
The authors found that MER can be adequately performed while the patient receives a desflurane anesthetic, and the results can serve as a guide for STN electrode implantation. This may be a good alternative surgical method in patients with PD who are unable to tolerate deep brain stimulation surgery with local anesthesia.
Effect of nerve graft porosity on the refractory period of regenerating nerve fibers
Authors: Vleggeert-Lankamp Carmen L. A. M. , Wolfs Jasper , Pêgo Ana Paula , van den Berg Rutgeris , Feirabend Hans , Lakke Egbert 
Published: July 2008

ObjectIn the present study the authors consider the influence of the porosity of synthetic nerve grafts on peripheral nerve regeneration.MethodsMicroporous (1–13 μm) and nonporous nerve grafts made of a copolymer of trimethylene carbonate and ε-caprolactone were tested in an animal model. Twelve weeks after surgery, nerve and muscle morphological and electrophysiological results of regenerated nerves that had grown through the synthetic nerve grafts were compared with autografted and untreated (control) sciatic nerves. Based on the observed changes in the number and diameter of the nerve fibers, the predicted values of the electrophysiological parameters were calculated.ResultsThe values of the morphometric parameters of the peroneal nerves and the gastrocnemius and anterior tibial muscles were similar if not equal in the rats receiving synthetic nerve grafts. The refractory periods, however, were shorter in porous compared with nonporous grafted nerves, and thus were closer to control values.ConclusionsA shorter refractory period enables the axon to follow the firing frequency of the neuron more effectively and allows a more adequate target organ stimulation. Therefore, porous are preferred over nonporous nerve grafts.