bluuebunny/crossref_metadata_2025_split huggingface dataset:
Arrangement and fine structure of collagen fibrils in the decidualized mouse endometrium
Authors: Carbone Karin , Pinto Nilda M.P. , Abrahamsohn Paulo A. , Zorn Telma M.T. 
Published: January 2006

AbstractThe adaptations of the mouse uterus to pregnancy include extensive modifications of the cells and extracellular matrix of the endometrial connective tissue that surround the embryos. Around each implanted embryo this tissue redifferentiates into a transient structure called decidua, which is formed by polygonal cells joined by intercellular junctions. In the mouse, thick collagen fibrils with irregular profile appear in decidualized areas of the endometrium but not in the nondecidualized stroma and interimplantation sites. The fine organization of these thick fibrils has not yet been established. This work was addressed to understand the arrangement and fine structure of collagen fibrils of the decidua of pregnant mice during the periimplantation stage. Major modifications occurred in collagen fibrils that surrounded decidual cells: (1) the fibrils, which were arranged in parallel bundles in nonpregnant animals, became organized as baskets around decidual cells; (2) very thick collagen fibrils with very irregular profiles appeared around decidual cells. Analysis of replicas and serial sections suggests that the thick collagen fibrils form by the lateral aggregation of thinner fibrils to a central fibril resulting in very irregular profile observed in cross sections of thick fibrils. The sum of modifications of the collagen fibrils seem to represent an adaptation of the endometrium to better support the decidual cells while they hold the embryos during the beginning of their development. The deposition of thick collagen fibrils in the decidua may contribute to form a barrier that impedes leukocyte migration within the decidua, preventing immunological rejection of genetically dissimilar embryonic tissues. Microsc. Res. Tech. 69:36–45, 2006. © 2006 Wiley‐Liss, Inc.
Effects of aging and HIF‐1α deficiency on permeability of hippocampal vessels
Authors: Ueno Masaki , Tomita Shuhei , Nakagawa Toshitaka , Ueki Masaaki , Iwanaga Yasuyuki , Ono Jun‐Ichiro , Onodera Masayuki , Huang Cheng‐Long , Kanenishi Kenji , Shimada Atsuyoshi , Maekawa Nobuhiro , Sakamoto Haruhiko 
Published: January 2006

AbstractWe examined age‐related changes in the blood–brain barrier (BBB) of neural cell‐specific hypoxia inducible factor‐1α (HIF‐1α) deficient mice, which showed hydrocephalus with neuronal cell loss, to investigate an effect of neural cell‐specific HIF‐1α deficiency or hydrocephalus on vascular function. Vascular permeability of horseradish peroxidase (HRP) and binding of cationized ferritin (CF) particles to the endothelial cell luminal surface, as a marker of glycocalyx, were investigated. The thickness of CF‐labeled glycocalyx was significantly decreased in the cortex in mutant mice compared with that of control mice, although it was not paralleled by increased vascular permeability. In addition, strong staining for HRP was seen around vessels located along the hippocampal fissure in 24‐month‐old mutant mice. The reaction product of HRP appeared in an increasing number of the endothelial cell abluminal vesicles and within the thickened basal lamina of arterioles in the hippocampus, showing increased vascular permeability. There were no leaky vessels in 10‐week‐old mutant mice or 10‐week‐old and 24‐month‐old control mice. These findings suggest the necessity of two factors, aging and hydrocephalus, for BBB dysfunction in HIF‐1α deficient mice. Microsc. Res. Tech. 69:29–35, 2006. © 2006 Wiley‐Liss, Inc.
Dynamic‐SIMS imaging and quantification of inorganic ions in frozen‐hydrated plant samples
Authors: Dérue Cedric , Gibouin David , Demarty Maurice , Verdus Marie‐Claire , Lefebvre Fabrice , Thellier Michel , Ripoll Camille 
Published: January 2006

AbstractWe present here SIMS images of the distribution of inorganic cations (Na, K, Mg and Ca) in frozen‐hydrated samples of three plant species, ivy, camomile, and flax. The samples were cryofixed using fast plunge‐freezing. Stigmatic images were obtained, at 100 K, under dynamic SIMS conditions by fast atom bombarding (FAB). Even though the images obtained with the frozen‐hydrated plant samples are still not of upper quality, they show that the method used to prepare these samples preserves existing ionic gradients between the outer and the inner part of the cells, between adjacent cells, including cells with the same type of differentiation, and between tissues. We also describe the quantification of the relative proportions of the ions in the vacuoles of flax. The reasonable accuracy achieved for quantification of the vacuole ion ratios permitted to show (i) that radial gradients of ion ratios in hypocotyls change when the plant is becoming older and (ii) that large differences may exist between adjacent cortical cells of the same type. The role of these substantial differences in vacuole ion balance ratios is a largely unexplored issue in plant physiology. Microsc. Res. Tech. 69:53–63, 2006. © 2006 Wiley‐Liss, Inc.
Antennal and Cephalic organelles in the social wasp Paravespula germanica (Hymenoptera, Vespinae): Form and possible function
Authors: Agmon Ifaat , Plotkin Marian , Ermakov Natalya Y. , Barkay Zahava , Ishay Jacob S. 
Published: January 2006

AbstractThis paper deals with hairs and organelles present on the head and antennae of the German wasp, Paravespula germanica, and their possible role in sensing the physical and chemical ambience, as well as in intercommunicating both while in flight outside or in the nest. Via scanning electron microscope photography, we detected on the frons plate of the wasp's head, hairs that were about 300 μm long and comprised the longest hairs on the body of the wasps. Additionally, the two antennae bore along their entire length photoreceptors, placoids, campaniforms, trichoids, and agmons. These organelles are located at high but variable density along the antennal segments. The paper provides the dimensions of each of the mentioned organelles, and discusses the possible functions of the organelles as well as of the hairs on the frons. Photographs taken via atomic force microscope reveal that the epicuticle of the antenna is of two typical shapes; one, bearing both longitudinal stripes as well as transverse bands that are about 1 μm in width, and a second granulated form. Conceivably, the wasp uses the various organelles mentioned to communicate with its mates that are some distance away, somewhat like the use of radar by humans. Microsc. Res. Tech. 69:46–52, 2006. © 2006 Wiley‐Liss, Inc.
Interembryonic regions of the uterus of the viviparous lizard Mabuya brachypoda (Squamata: Scincidae)
Authors: Uribe‐Aranzábal Mari Carmen , Hernández‐Franyutti Arlette , Guillette Louis J. 
Published: January 2006

AbstractAnalysis of the structure and physiology of the uterine incubation chambers of viviparous squamates has provided insight concerning adaptations for gestation. However, the literature addressing the biology of the interembryonic regions of the uterus is very limited, presumably because it has been assumed that this area has little role in the development and support of embryos in viviparous squamates. This study was undertaken to examine the histology of the interembryonic regions of Mabuya brachypoda, a viviparous lizard with microlecithal ova and consequently substantial matrotrophic activity. The incubation chambers are oval, distended zones of the uterus, adjacent to the interembryonic regions. The wall of the interembryonic regions includes: mucosa, formed by a cubodal or columnar epithelium with ciliated and nonciliated cells, and a lamina propria of vascularized connective tissue containing abundant acinar glands; myometrial smooth muscle consisting of inner circular and outer longitudinal layers; and serosa. The segment of the interembryonic region adjacent to the incubation chamber forms a transitional segment that displays folds of the mucosa that protrude into the uterine lumen. The limit of the incubation chamber is well defined by the long mucosal folds of the transitional segment. Long and thin extensions of extraembryonic membranes are present in the lumen of the transitional segment, outside of the incubation chamber region. The presence of abundant uterine glands and extraembryonic membranes in the interembryonic regions during gestation suggests uterine secretory activity and histotrophic transfer of nutrients to embryos in these regions. J. Morphol. © 2006 Wiley‐Liss, Inc.
Optimized clinical T2 relaxometry with a standard CPMG sequence
Authors: Pell Gaby S. , Briellmann Regula S. , Waites Anthony B. , Abbott David F. , Lewis David P. , Jackson Graeme D. 
Published: January 2006

AbstractPurposeTo optimize the accuracy and precision of T2 measurements using the standard Carr‐Purcell‐Meiboom‐Gill (CPMG) sequence. T2 values obtained with this technique are normally sensitive to imperfect refocusing due to the formation of unwanted stimulated echoes.Materials and MethodsModifications are made to the refocusing slice selection width and the interleaving scheme. A widened refocusing slice improves the uniformity of the refocusing flip angle across the slice. A slow spin echo acquisition provided “gold standard” T2 values. Repeated T2 measurements in phantom and human studies are used to compare the accuracy and precision of the optimized and non‐optimized CPMG implementations.ResultsThe required slice thickness ratio between refocusing and excitation slice widths is found to be 3:1 for typical optimized radiofrequency pulses. T2 values obtained using this optimized implementation more closely correspond to “gold standard” values. Repeated T2 measurements indicate significantly improved correspondence between data and model. A reduction in the fitting error of approximately 70% is demonstrated for phantoms.ConclusionWe demonstrate that a relatively simple change to the CPMG relaxometry sequence parameters from the default setup yields significant improvements in the accuracy and precision of T2 measurements. J. Magn. Reson. Imaging 2006. © 2006 Wiley‐Liss, Inc.
Hepatocellular carcinoma missed on gadolinium enhanced MR imaging, discovered in liver explants: Retrospective evaluation
Authors: Karadeniz‐Bilgili Mirace Y. , Braga Larissa , Birchard Katherine R. , Gerber David , Firat Zeynep , Woosley John T. , Shrestha Roshan , Semelka Richard C. 
Published: January 2006

AbstractThe main purpose of this study was to determine if hepatocellular carcinomas (HCCs) missed on prospective magnetic resonance (MR) study could be identified on retrospective MR analysis, and to determine the cause for misdiagnosis. Among 555 patients who underwent liver transplantation between 1993 and 2004, 279 were imaged with MR imaging and four of these revealed HCCs in explanted livers that were not reported on prospective MR reading. The main cause of missed lesions were suboptimal image quality due to inability of patients to suspend respiration; other causes were HCC misinterpreted as high‐grade dysplastic nodule and isoenhancement of HCC on early phase images. J. Magn. Reson. Imaging 2006. © 2006 Wiley‐Liss, Inc.
A parallel approach to STAP implementation for fMRI data
Authors: Thompson Elizabeth A. 
Published: January 2006

AbstractPurposeTo exploit the capabilities of parallel processing in applying the space‐time adaptive processing (STAP) algorithm, previously explored on a small scale for functional magnetic resonance imaging (fMRI) applications, to conventional size fMRI data sets.Materials and MethodsSTAP is a two‐dimensional filter that is able to locate fMRI activations in both space and frequency. It is applied here for the construction of brain activation maps in fMRI using Visual Age® C, incorporating Engineering and Scientific Subroutine Library (ESSL®) functions, compiled in 64‐bit, and executed on an IBM SP supercomputer.ResultsComputer simulations incorporating actual MRI noise indicate that STAP, incorporated using the method of steepest descent, is feasible on conventional size data sets and exhibits an improvement in detecting activations over the more traditional cross correlation method of fMRI analysis when the response is unknown.ConclusionSTAP is feasible on traditional size fMRI data sets and useful in elucidating spatial and temporal connectivity. J. Magn. Reson. Imaging 2006. © 2006 Wiley‐Liss, Inc.
Repeatability of functional MRI for conformal avoidance radiotherapy planning
Authors: Garcia‐Alvarez Roberto , Liney Gary P. , Beavis Andrew W. 
Published: January 2006

AbstractPurposeTo establish the repeatability of functional magnetic resonance imaging (fMRI) examinations in order to develop an appropriate margin for functional organs at risk (fOAR) in the radiotherapy planning process.Materials and MethodsThis work investigates the variability of motor cortex activation in the left and right hemispheres of 15 normal subjects. The uncertainty of the absolute position and volume of the activation was determined for each volunteer by repeating the fMRI examination three times in a single scan session.ResultsOur study proposes the use of 2.9 mm and 2.2 mm margins for the left and right motor cortices, respectively.ConclusionFrom the sample of 15 volunteers we established an appropriate planning margin that is considered to represent the uncertainty in spatially measuring the fOAR for a single fMRI examination. The work will be of interest to anyone investigating the clinical robustness of fMRI. J. Magn. Reson. Imaging 2006. © 2006 Wiley‐Liss, Inc.
Feasibility of k‐t BLAST technique for measuring “seven‐dimensional” fluid flow
Authors: Marshall Ian 
Published: January 2006

AbstractPurposeTo investigate the feasibility of rapid MR measurement of “seven‐dimensional” (three velocity components, three dimensions, and time) fluid flow using the k‐t Broad‐use Linear Acquisition Speed‐Up Technique (BLAST).Materials and MethodsComplete k‐space data were acquired for pulsatile fluid flow in a model of a stenosed carotid bifurcation. The data was subsampled to simulate “training” and “accelerated acquisition” data for reconstruction using k‐t BLAST.ResultsFlow waveforms estimated from k‐t BLAST reconstructions were in good agreement with those measured from the full data set for overall speedup factors up to approximately four times when slice‐by‐slice undersampling in ky was used. Accuracy was better than 25 mm/second or 7% (root‐mean‐square error) for individual time frames under these conditions. Flow patterns in the plane of symmetry, near the bifurcation, and in the stenosis were also in good agreement with those reconstructed from the full data set. Improved performance was obtained from undersampling in both ky and kz, when acceleration factors up to 12 times gave acceptable results.ConclusionThe k‐t BLAST technique can be applied to flow quantification, and may make feasible the acquisition of time‐resolved blood flow from extended arterial regions within acceptable examination times. J. Magn. Reson. Imaging 2006. © 2006 Wiley‐Liss, Inc.
Toward rapid high resolution in vivo intravascular MRI: Evaluation of vessel wall conspicuity in a porcine model using multiple imaging protocols
Authors: Hillenbrand Claudia M. , Jesberger John A. , Wong Eddy Y. , Zhang Shaoxiong , Chang David T. , Wacker Frank K. , Lewin Jonathan S. , Duerk Jeffrey L. 
Published: January 2006

AbstractPurposeTo assess magnetic resonance (MR) pulse sequences for high resolution intravascular imaging.Materials and MethodsIntravascular imaging of the abdominal aorta and iliac arteries was performed in vivo in a porcine model at 1.5 T using catheter‐mounted micro‐receive coils. Ten protocols, including spin‐echo (SE)‐echo planar imaging (SE‐EPI), segmented EPI, half‐Fourier single‐shot turbo spin‐echo (HASTE), fast imaging with steady‐state free precession (TrueFISP), turbo spin‐echo (TSE), and SE acquisition schemes were employed in 13 trials. Images were analyzed by six expert raters with respect to wall‐conspicuity, wall‐to‐lumen/tissue contrast, visible layers of the arterial wall, anticipated clinical usefulness, and overall image quality. Mean differences between sequence‐types were evaluated using analysis of variance (ANOVA) between groups with planned comparisons.ResultsThe vessel wall was delineated in almost all protocols. Motion artifacts from physiological and device motion were reduced in fast techniques. The best contrast between the wall and surrounding tissue was provided by a HASTE protocol. Anatomic layers of the vessel wall were best depicted on dark blood T2‐weighted TSE. Overall, TrueFISP was ranked highest on the remaining measures.ConclusionDedicated catheter‐coils combined with fast sequences have potential for in vivo characterization of vessel walls. TrueFISP offered the best overall image quality and acquisition speed, but suffered from the inability to delineate the multiple layers of the wall, which seems associated with dark blood‐ and T2‐weighted contrast. We believe future intra‐arterial trials should proceed from this study in normal artery imaging and initially focus on fast T2‐weighted dark blood techniques in trials with pathology. J. Magn. Reson. Imaging 2006. © 2006 Wiley‐Liss, Inc.
Quantitative phase‐contrast flow MRI measurements in the presence of a second vessel closely positioned to the examined vessel
Authors: Lagerstrand Kerstin M. , Vikhoff‐Baaz Barbro , Starck Göran , Forssell‐Aronsson Eva 
Published: January 2006

AbstractPurposeTo examine the influence of the truncated sampling of k‐space data on the accuracy of phase‐contrast (PC) flow quantifications in the presence of nearby vessels.Materials and MethodsComputer simulations were performed along with some experimental validations on a flow phantom and a normal subject.ResultsThe accuracy of the PC flow quantification decreased when a second vessel was positioned closely to the examined vessel. The effect strongly depended on the peak flow velocity in the second vessel relative to the velocity encoding (venc) level of the MRI acquisition, and on the position and area of the second vessel.ConclusionDue to the truncated sampling of the k‐space data, signal leaked from nearby vessels and distorted the PC flow quantification in the examined vessel. The presented results suggest specific experimental conditions to minimize this flow quantification error. J. Magn. Reson. Imaging 2006. © 2006 Wiley‐Liss, Inc.
Subjects' expectations in neuroimaging research
Authors: Kirschen Matthew P. , Jaworska Agnieszka , Illes Judy 
Published: January 2006

AbstractPurposeTo explore subjects' attitudes and expectations concerning the detection and management of incidental findings in neuroimaging research.Materials and MethodsHealthy control subjects (N = 105) who previously participated in neuroimaging studies in medical and nonmedical settings were surveyed about their expectations and attitudes toward unexpected clinical findings on their research brain scans. We hypothesized that even though the participants consented to a scanning procedure for research purposes alone, they would still expect pathology, if present, to be detected and reported to them.ResultsFifty‐four percent of participants reported that they expected research scans to detect abnormalities if they existed. Nearly all subjects (>90%) reported that they would want findings communicated to them, and many (59%) preferred this to be done by a physician affiliated with the research team. The participants responded in similar ways whether they were scanned in medical or nonmedical settings.ConclusionClarity about procedures for handling incidental findings when obtaining written and verbal informed consent is essential to ensure that the subjects' expectations are consistent with the purpose and scope of the research. J. Magn. Reson. Imaging 2006. © 2006 Wiley‐Liss, Inc.
Magnetic resonance imaging of myocardial infarction using a manganese‐based contrast agent (EVP 1001‐1): Preliminary results in a Dog model
Authors: Storey Pippa , Chen Qun , Li Wei , Seoane Peter R. , Harnish Phillip P. , Fogelson Laura , Harris Kathleen R. , Prasad Pottumarthi V. 
Published: January 2006

AbstractPurposeTo investigate the MRI characteristics of an intracellular manganese‐based contrast agent, EVP 1001‐1 (Eagle Vision Pharmaceutical Corp.), in a canine model of myocardial infarction.Materials and MethodsThree dogs were imaged 14–37 days following permanent ligation of the left anterior descending coronary artery (LAD). Measurements of the longitudinal relaxation rate R1 were made prior to EVP 1001‐1 administration (20 μmol/kg i.v.) and for one hour thereafter. Triphenyl tetrazolium chloride (TTC) staining was used to document infarction.ResultsIn normal myocardium, EVP 1001‐1 produced a substantial increase in the longitudinal relaxation rate, which remained fairly constant over the postcontrast imaging period (ΔR1= 1.47 ± 0.58 sec−1 (mean ± SD) at 35 minutes, P < 0.05). In the infarct, the response to EVP 1001‐1 was small or negligible (ΔR1= 0.27 ± 0.28 sec−1). This resulted in a significant postcontrast difference in relaxation rate between normal and infarcted tissue (R1(normal) − R1(infarct) = 1.08 ± 0.26 sec−1, P < 0.05). The infarct remained clearly delineated in all animals throughout the steady‐state imaging period, and qualitatively matched TTC results.ConclusionThe persistent enhancement pattern revealed by MRI following EVP 1001‐1 administration may be beneficial for identifying and characterizing myocardial infarction. J. Magn. Reson. Imaging 2006. © 2006 Wiley‐Liss, Inc.
Monoclonal antibodies to distinct regions of human myelin proteolipid protein simultaneously recognize central nervous system myelin and neurons of many vertebrate species
Authors: Greenfield Edward A. , Reddy Jayagopala , Lees Andrew , Dyer Charissa A. , Koul Omanand , Nguyen Khuong , Bell Shannon , Kassam Nasim , Hinojoza Julian , Eaton Mary Jane , Lees Marjorie B. , Kuchroo Vijay K. , Sobel Raymond A. 
Published: January 2006

AbstractMyelin proteolipid protein (PLP), the major protein of mammalian CNS myelin, is a member of the proteolipid gene family (pgf). It is an evolutionarily conserved polytopic integral membrane protein and a potential autoantigen in multiple sclerosis (MS). To analyze antibody recognition of PLP epitopes in situ, monoclonal antibodies (mAbs) specific for different regions of human PLP (50–69, 100–123, 139–151, 178–191, 200–219, 264–276) were generated and used to immunostain CNS tissues of representative vertebrates. mAbs to each region recognized whole human PLP on Western blots; the anti‐100–123 mAb did not recognize DM‐20, the PLP isoform that lacks residues 116–150. All of the mAbs stained fixed, permeabilized oligodendrocytes and mammalian and avian CNS tissue myelin. Most of the mAbs also stained amphibian, teleost, and elasmobranch CNS myelin despite greater diversity of their pgf myelin protein sequences. Myelin staining was observed when there was at least 40% identity of the mAb epitope and known pgf myelin proteins of the same or related species. The pgf myelin proteins of teleosts and elasmobranchs lack 116–150; the anti‐100–123 mAb did not stain their myelin. In addition to myelin, the anti‐178–191 mAb stained many neurons in all species; other mAbs stained distinct neuron subpopulations in different species. Neuronal staining was observed when there was at least approximately 30% identity of the PLP mAb epitope and known pgf neuronal proteins of the same or related species. Thus, anti‐human PLP epitope mAbs simultaneously recognize CNS myelin and neurons even without extensive sequence identity. Widespread anti‐PLP mAb recognition of neurons suggests a novel potential pathophysiologic mechanism in MS patients, i.e., that anti‐PLP antibodies associated with demyelination might simultaneously recognize pgf epitopes in neurons, thereby affecting their functions. © 2006 Wiley‐Liss, Inc.