bluuebunny/crossref_metadata_2025_split huggingface dataset:
Chemotactic peptide fMetLeuPhe induces translocation of the TRPV2 channel in macrophages
Authors: Nagasawa Masahiro , Nakagawa Yuko , Tanaka Shigeyasu , Kojima Itaru 
Published: December 2006

AbstractThe present study was conducted to characterize the regulation and function of TRPV2 in macrophages. Among six members of the TRPV family channels, only the expression of TRPV2 was detected in macrophages. We then determined localization of TRPV2 using TtT/M87 macrophages transfected with TRPV2‐EGFP. In serum‐free condition, most of the TRPV2 signal was located in the cytoplasm and colocalized with the endoplasmic reticulum marker. Treatment with serum induced translocation of some of the TRPV2‐EGFP to the plasma membrane. Serum‐induced translocation was blocked by transfection of short‐form TRPV2 (s‐TRPV2) lacking a pore‐forming region and the sixth transmembrane domain. Addition of a chemotactic peptide formyl Met‐Leu‐Phe (fMLP) also induced translocation of TRPV2‐EGFP to the plasma membrane. The fMLP‐induced translocation was blocked by an inhibitor of PI 3‐kinase, LY294002, and pertussis toxin. Whole‐cell patch clamp analysis showed a Cs+ current in the TtT/M87 cell, which was blocked by an addition of ruthenium red and transfection of either s‐TRPV2 or siRNA for TRPV2. fMLP increased the Cs+ current. fMLP induced a rapid and sustained elevation of cytoplasmic Ca2+ ([Ca2+]C), the sustained phase of which was abolished by removal of extracellular calcium. The sustained elevation of [Ca2+]C was also blocked by ruthenium red, and transfection of either s‐TRPV2 or siRNA. Finally, fMLP‐induced migration of macrophage was blocked by ruthenium red or transfection of s‐TRPV2. These results suggest that fMLP induces translocation of TRPV2 from intracellular compartment to the plasma membrane, and this translocation is critical for fMLP‐induced calcium entry. J. Cell. Physiol. 210: 692–702, 2007. © 2006 Wiley‐Liss, Inc.
Effect of hepatocyte growth factor on methionine adenosyltransferase genes and growth is cell density‐dependent in HepG2 cells
Authors: Yang Heping , Magilnick Nathaniel , Noureddin Mazen , Mato José M. , Lu Shelly C. 
Published: December 2006

AbstractHepatocyte growth factor (HGF) is a potent hepatocyte mitogen but its effect in liver cancer is conflicting. Methionine adenosyltransferase (MAT) is an essential enzyme encoded by two genes (MAT1A and MAT2A), while a third gene (MAT2β) encodes for a subunit that regulates the MAT2A‐encoded isoenzyme. MAT1A is silenced while MAT2A and MAT2β are induced in hepatocellular carcinoma (HCC). The current work examined expression of HGF/c‐met in HCC and whether HGF regulates MAT genes and growth in HepG2 cells. We found the mRNA levels of HGF and c‐met are markedly increased in HCC. To study the influence of cell density, HepG2 cells were plated under high‐density (HD) or low‐density (LD) and treated with HGF (10 ng/ml). Cell density had a dramatic effect on MAT1A expression, being nearly undetectable at LD to a ninefold induction under HD. Cell density also determined the effect of HGF. At HD, HGF increased the mRNA levels of p21 and p27, while lowering the levels of MAT genes, cyclin A, and c‐met. At LD, HGF increased the mRNA levels of cyclin A, MAT2A, MAT2β, and c‐met. Consistently, HGF inhibits growth under HD but stimulates growth under LD. HGF induced sustained high ERK activation under HD as compared to LD. In summary, HGF induces genes favoring growth and is mitogenic when HepG2 cells are plated under LD; however, the opposite occurs under HD. This involves cell density‐dependent differences in HGF‐induced ERK activation. This may explain why HGF is mitogenic only when there is loss of cell‐cell contact in vivo. J. Cell. Physiol. 210: 766–773, 2007. © 2006 Wiley‐Liss, Inc.
Thrombospondin‐1 inhibits VEGF levels in the ovary directly by binding and internalization via the low density lipoprotein receptor‐related protein‐1 (LRP‐1)
Authors: Greenaway James , Lawler Jack , Moorehead Roger , Bornstein Paul , LaMarre Jonathan , Petrik Jim 
Published: December 2006

AbstractVEGF is a potent pro‐angiogenic factor whose effects are opposed by a host of anti‐angiogenic proteins, including thrombospondin‐1 (TSP‐1). We have previously shown that VEGF has important extravascular roles in the ovary and that VEGF and TSP‐1 are inversely expressed throughout the ovarian cycle. To date, however, a causal interaction between TSP‐1 and VEGF has not been identified. Here, we show that TSP‐1 has a direct inhibitory effect on VEGF by binding the growth factor and internalizing it via LRP‐1. Mice lacking TSP‐1 are subfertile and exhibited ovarian hypervascularization and altered ovarian morphology. Treatment of ovarian cells with TSP‐1 decreased VEGF levels and rendered the cells more susceptible to TNFα‐induced apoptosis. Knockdown of TSP‐1, through RNA interference, resulted in overexpression of VEGF and reduced cytokine‐induced apoptosis. In conclusion, we demonstrate a direct inhibitory effect of TSP‐1 on VEGF in the ovary. TSP‐1's regulation of VEGF appears to be an important mediator of ovarian angiogenesis and follicle development. J. Cell. Physiol. 210: 807–818, 2007. © 2006 Wiley‐Liss, Inc.
Calculating expected lung deposition of aerosolized administration of AAV vector in human clinical studies
Authors: Leung Kitty , Louca Emily , Munson Keith , Dutzar Benjamin , Anklesaria Pervin , Coates Allan L. 
Published: December 2006

AbstractBackgroundCystic fibrosis is an autosomal recessive disease affecting approximately 1 in 2500 live births. Introducing the cDNA that codes for normal cystic fibrosis transmembrane conductance regulator (CFTR) to the small airways of the lung could result in restoring the CFTR function. A number of vectors for lung gene therapy have been tried and adeno‐associated virus (AAV) vectors offer promise. The vector is delivered to the lung using a breath‐actuated jet nebulizer. The purpose of this project was to determine the aerosolized AAV (tgAAVCF) particle size distribution (PSD) in order to calculate target doses for lung delivery.MethodsA tgAAVCF solution was nebulized using the Pari LC Plus (n = 3), and the PSD was determined by coupling laser diffraction and inertial impaction (NGI) techniques. The NGI allowed for quantification of the tgAAVCF at each stage of impaction, ensuring that rAAV‐CFTR vector is present and not empty particles. Applying the results to mathematical algorithms allowed for the calculation of expected pulmonary deposition.ResultsThe mass median diameter (MMD) for the tgAAVCF was 2.78 ± 0.43 µm. If the system works ideally and the patient only receives aerosol on inspiration, the patient would receive 47 ± 0% of the initial dose placed in the nebulizer, with 72 ± 0.73% of this being deposited beyond the vocal cords.ConclusionsThis technology for categorizing the pulmonary delivery system for lung gene therapy vectors can be adapted for advanced aerosol delivery systems or other vectors. Copyright © 2006 John Wiley & Sons, Ltd.
Specific adeno‐associated virus serotypes facilitate efficient gene transfer into human and non‐human primate mesenchymal stromal cells
Authors: Chng Keefe , Larsen Stephen R. , Zhou Shangzhen , Wright J. Fraser , Martiniello‐Wilks Rosetta , Rasko John E. J. 
Published: December 2006

AbstractMesenchymal stromal cells (MSCs) show great promise for ex vivo gene and cell‐mediated therapies. The immunophenotype and in vitro differentiation capacity of primary baboon MSCs was demonstrated to be near‐identical to that observed in human MSCs. To optimize gene transfer efficiency, we compared the efficiency of serotypes 1, 2, 3, 4, 5, 6, and 8 of adeno‐associated virus (AAV) vectors for their ability to mediate transduction of human and baboon MSCs. AAV serotype 2 vectors were the most efficient in transducing MSCs from humans and baboons. As a reference, human Ad293 cells were transduced with these seven AAV serotypes, and were found to have the highest transduction levels followed by baboon MSCs, and then human MSCs. The order of increasing transduction efficiency for the serotypes tested was similar for human and baboon MSCs, but was different for human Ad293 cells. The transduction efficiency of MSCs isolated from different individuals was comparable within the same species. We also demonstrated that baboon MSCs transduced with AAV serotype 2 vectors retain their potential to differentiate into adipocytes in vitro, and can incorporate into injured muscle tissue of NODSCID mice in vivo. We detected β‐galactosidase reporter gene expression in host muscle tissue for up to 9 weeks in this study, indicating engraftment of transduced baboon MSCs and sustained transgene expression in vivo. Copyright © 2006 John Wiley & Sons, Ltd.
Breast MRI lesion classification: Improved performance of human readers with a backpropagation neural network computer‐aided diagnosis (CAD) system
Authors: Meinel Lina Arbash , Stolpen Alan H. , Berbaum Kevin S. , Fajardo Laurie L. , Reinhardt Joseph M. 
Published: December 2006

AbstractPurposeTo develop and test a computer‐aided diagnosis (CAD) system to improve the performance of radiologists in classifying lesions on breast MRI (BMRI).Materials and MethodsA CAD system was developed that uses a semiautomated segmentation method. After segmentation, 42 features based on lesion shape, texture, and enhancement kinetics were computed, and the 13 best features were selected and used as inputs to a backpropagation neural network (BNN). The BNN was trained and tested using the leave‐one‐out method on 80 BMRI lesions (37 benign, 43 malignant). Lesion histopathology was used as the reference standard. Five human readers classified the 80 lesions first without and then with CAD assistance. The performance of the computer classifier and the human readers was assessed using receiver operating characteristic curves; the performance of the human readers was also evaluated using multireader multicase (MRMC) analysis.ResultsThe performance of the human readers significantly improved when aided by the CAD system (P< 0.05). MRMC analysis showed that human reader performance with and without CAD system assistance can be generalized to the population of cases (P< 0.001).ConclusionA CAD system based on lesion morphology and enhancement kinetics can improve the performance of human readers in classifying lesions on breast MRI. J. Magn. Reson. Imaging 2007. © 2006 Wiley‐Liss, Inc.
Diagnostic accuracy of high‐resolution MRI using a microscopy coil for patients with presumed DCIS following mammography screening
Authors: Zhu Jingzhi , Kurihara Yasuyuki , Kanemaki Yoshihide , Ogata Haruki , Fukuda Mamoru , Nakajima Yasuo , Maeda Ichiro 
Published: December 2006

AbstractPurposeTo prospectively evaluate the accuracy of high‐resolution (HR)‐MRI as a secondary examination in women with abnormal calcifications detected on mammography.Materials and MethodsWe used a 4.7‐cm microscopy coil to acquire HR‐MRI signal data. We examined 52 women with breast lesions preoperatively using HR‐MRI and vacuum‐assisted core needle biopsy. The lesions were suspicious of malignancy, classified as category 3–5 on mammography (Breast Imaging Reporting and Data System [BI‐RADS]), and without a palpable mass. All visualized suspicious lesions were correlated with histological findings. We compared the HR‐MRI and pathological findings and calculated the sensitivity, specificity, and accuracy.ResultsWe compared the breast HR‐MRI results with the gold standard of pathological results for studies of malignancy (DCIS and invasive cancer), and found a sensitivity of 88.5%, specificity of 92.3%, and accuracy of 90.4%. The positive predictive value (PPV) was 92%, and the negative predictive value (NPV) was 88.9%. When breast MRI was compared with pathological results for studies that diagnosed DCIS only, the results revealed a sensitivity of 88.6%, specificity of 88.2%, accuracy of 88.5%, PPV of 93.9%, and NPV of 78.9%.ConclusionHR‐MRI using a microscopy coil is a useful, reliable, safe, and minimally invasive procedure that is a good choice for secondary assessment of abnormal calcification in the breast. J. Magn. Reson. Imaging 2007. © 2006 Wiley‐Liss, Inc.
Magnetic resonance voiding cystourethrography for vesicoureteral reflux
Authors: Takazakura Ryutaro , Johnin Kazuyoshi , Furukawa Akira , Nitta Norihisa , Takahashi Masashi , Okada Yusaku , Murata Kiyoshi 
Published: December 2006

AbstractPurposeTo assess the feasibility of magnetic resonance voiding cystourethrography (MRVCUG) using MR fluoroscopy for evaluation of vesicoureteral reflux (VUR), and its use as a noninvasive alternative to standard VCUG.Materials and MethodsA total of 22 MR studies of 16 patients (five months to 41 years old) with primary VUR diagnosed by standard VCUG were evaluated. Six patients underwent MR studies and standard VCUG pre‐ and postoperatively. MR fluoroscopy was executed with a non‐enhanced heavily T2‐weighted single‐shot fast spin‐echo (FSE) sequence. The MR findings were correlated with those obtained by the gold standard, standard VCUG.ResultsOf the 44 kidney‐ureter units, 20 were refluxing on MRVCUG and 21 were refluxing on standard VCUG. There were one false‐positive and two false‐negative units. MRVCUG was 90% sensitive with a specificity of 96% for detecting VURs that were calculated based on kidney‐ureter units. Two false‐negative units were found in mild cases (grade I and II). For the units of grade III, IV, and V (high‐grade reflux), MRVCUG detected all of the refluxing renal collecting systems.ConclusionMRVCUG can demonstrate high‐grade reflux without ionizing radiation or catheterization. J. Magn. Reson. Imaging 2007. © 2006 Wiley‐Liss, Inc.
Sensitivity comparison of multiple vs. single inversion time pulsed arterial spin labeling fMRI
Authors: van Osch Matthias J.P. , Hendrikse Jeroen , van der Grond Jeroen 
Published: December 2006

AbstractPurposeTo study the sensitivity for detection of activation for multiple vs. single inversion time (TI) pulsed arterial spin labeling (PASL).Materials and MethodsThe number of activated voxels and the mean t‐statistic over activated voxels was measured by means of multiple and single TI PASL sequences in five volunteers during visual stimulation by means of an alternating checkerboard. Acquisition was performed by means of the transfer insensitive labeling technique (TILT) and TURBO‐TILT.ResultsIt was found that the sensitivity for the detection of activation was lower for an individual TI out of a multiple TI sequence than for the corresponding single TI acquisition of equal duration. After averaging over all TIs between and including 600 and 1400 msec, the number of activated voxels and mean t‐statistic were no longer statistically lower for the multiple TI sequence than for the single TI experiment.ConclusionMultiple TI PASL can be used for functional MRI (fMRI) studies, when performing the detection of activated brain regions on data that is averaged over all TIs between 600 and 1400 msec. Subsequently the multi‐TI data can be used to quantify cerebral blood flow (CBF) changes upon activation. Additionally, we have shown that single TI PASL fMRI overestimates the CBF changes upon activation due to transit time changes. J. Magn. Reson. Imaging 2007. © 2006 Wiley‐Liss, Inc.
MRI of the lung: Value of different turbo spin‐echo, single‐shot turbo spin‐echo, and 3D gradient‐echo pulse sequences for the detection of pulmonary metastases
Authors: Bruegel Melanie , Gaa Jochen , Woertler Klaus , Ganter Carl , Waldt Simone , Hillerer Claudia , Rummeny Ernst J. 
Published: December 2006

AbstractPurposeTo compare the value of different MRI sequences of the lung for the detection of pulmonary metastases.Materials and MethodsA total of 28 patients with 225 pulmonary metastases confirmed at multidetector‐row computed tomography (MDCT) underwent MRI of the lung, including breathhold T2‐weighted single‐shot turbo spin‐echo (half‐Fourier single‐shot turbo spin‐echo [HASTE] and inversion recovery [IR]‐HASTE) and conventional turbo spin‐echo (TSE and short‐tau inversion recovery [STIR]) sequences, a respiratory‐ and pulse‐triggered black‐blood STIR sequence (triggered STIR), and breathhold pre‐ and postcontrast volumetric interpolated 3D gradient‐echo (VIBE) sequences. MR images were reviewed by three independent observers and results were correlated with MDCT, which served as standard of reference. Lesion‐to‐lung contrast‐to‐noise ratios (CNRs) and image artifacts were also assessed.ResultsCNRs were highest on TSE images (P < 0.001). Mean sensitivities for lesion detection with triggered STIR, TSE, and STIR were 72.0%, 69.0%, and 63.4%, respectively. With HASTE, IR‐HASTE, and pre‐ and postcontrast VIBE, significantly lower sensitivities were obtained (P < 0.05), although artifacts due to physiological motion were less distinct with these sequences compared to TSE and STIR (P < 0.05).ConclusionConventional TSE sequences are more sensitive in depicting pulmonary metastases than single‐shot TSE or 3D gradient‐echo sequences. Respiratory and pulse triggering can improve lesion detection, but increases acquisition time substantially. J. Magn. Reson. Imaging 2007. © 2006 Wiley‐Liss, Inc.
Detection and validated quantification of nine herbal phenalkylamines and methcathinone in human blood plasma by LC‐MS/MS with electrospray ionization
Authors: Beyer Jochen , Peters Frank T. , Kraemer Thomas , Maurer Hans H. 
Published: December 2006

AbstractThe herbal stimulants Ephedra species, Catha edulis (khat), and Lophophora williamsii (peyote) have been abused for a long time. In recent years, the herbal drug market has grown owing to publicity on the Internet. Some ingredients of these plants are also ingredients of cold remedies. The aim of the presented study is to develop a multianalyte procedure for detection and validated quantification of the phenalkylamines ephedrine, pseudoephedrine, norephedrine, norpseudoephedrine, methylephedrine, methylpseudoephedrine, cathinone, mescaline, synephrine (oxedrine), and methcathinone in plasma. After mixed‐mode solid‐phase extraction of 1 ml of plasma, the analytes were separated using a strong cation exchange separation column and gradient elution. They were detected using a Q‐Trap LC‐ESI‐MS/MS system (MRM mode). Calibration curves were used for quantification using norephedrine‐d3, ephedrine‐d3, and mescaline‐d9 as internal standards. The method was validated according to international guidelines. The assay was selective for the tested compounds. It was linear from 10 to 1000 ng/ml for all analytes. The recoveries were generally higher than 70%. Accuracy ranged from − 0.8 to 20.0%, repeatability from 2.5 to 12.3%, and intermediate precision from 4.6 to 20.0%. The lower limit of quantification was 10 ng/ml for all analytes. No instability was observed after repeated freezing and thawing or in processed samples. The applicability of the assay was tested by analysis of authentic plasma samples after ingestion of different cold medications containing ephedrine or pseudoephedrine, and after ingestion of an aqueous extract of Herba Ephedra. After ingestion of the cold medications, only the corresponding single alkaloids were detected in human plasma, whereas after ingestion of the herb extract, all six ephedrines contained in the plant were detected. The presented LC‐MS/MS assay was found applicable for sensitive detection and accurate and precise quantification of all studied analytes in plasma. Copyright © 2006 John Wiley & Sons, Ltd.
Leaving group effects on the selectivity of the gas‐phase fragmentation reactions of side chain fixed‐charge‐containing peptide ions
Authors: Roberts Kade D. , Reid Gavin E. 
Published: December 2006

AbstractThe effect of trialkylsulfonium versus quaternaryalkylammonium ions on the multistage gas‐phase fragmentation reactions of side chain, fixed‐charge, cysteine‐containing peptides has been examined in a quadrupole linear ion trap. These tandem mass spectrometry experiments reveal that selective loss of dialkylsulfide from fixed‐charge sulfonium ion derivatives is the dominant fragmentation pathway regardless of the degree of proton mobility, indicating that it is the most energetically favored fragmentation pathway. In contrast, the loss of trimethylamine from the side chain of fixed‐charge ammonium‐ion‐containing cysteine derivatives appears to be less energetically favored, and as a result extensive charge‐remote fragmentation is observed under low proton mobility conditions, while under conditions of high proton mobility, amide bond fragmentation reactions dominate. These findings are supported by molecular orbital calculations at the B3LYP/6‐31 + G(d, p) level of theory, which showed that the neutral loss of dimethylsulfide is both thermodynamically and kinetically preferred over the loss of trimethylamine. Copyright © 2006 John Wiley & Sons, Ltd.
Regeneration of nigrostriatal dopaminergic axons by degradation of chondroitin sulfate is accompanied by elimination of the fibrotic scar and glia limitans in the lesion site
Authors: Li Hong‐Peng , Homma Akiko , Sango Kazunori , Kawamura Koki , Raisman Geoffrey , Kawano Hitoshi 
Published: December 2006

AbstractChondroitin sulfate increases around a lesion site after central nervous system injury and is believed to be an impediment to axonal regeneration, because administration of chondroitinase ABC, a chondroitin sulfate‐degrading enzyme, promotes axonal regeneration of central neurons. To examine the physiological role of chondroitin sulfate up‐regulation after injury, the nigrostriatal dopaminergic axons were unilaterally transected in mice, and chondroitinase ABC was then injected into the lesion site. In mice transected only, tyrosine hydroxylase‐immunoreactive axons did not extend across the lesion at 1 or 2 weeks after the transection. Immunoreactivities of chondroitin sulfate side chains and core protein of NG2 proteoglycan increased in and around the lesion site, and a fibrotic scar containing type IV collagen deposits developed in the lesion center. In contrast, in mice transected and treated with chondroitinase ABC, numerous tyrosine hydroxylase‐immunoreactive axons were regenerated across the lesion at 1 and 2 weeks after the transection. In these animals, chondroitin sulfate immunoreactivity remarkably decreased, and immunoreactivity of 2B6 antibody, which recognizes the stub of degraded chondroitin sulfate side chains, was enhanced. Furthermore, the formation of a fibrotic scar and a glia limitans that surrounds the former was completely prevented, although type IV collagen immunoreactivity remained in newly formed blood capillaries around the lesion site. We discuss the question of whether the chondroitin sulfate is acting as a direct inhibitor of axonal regeneration or whether the observed changes are due to a prevention of the fibrotic scar formation and a rearrangement of astrocytic membranes. © 2006 Wiley‐Liss, Inc.