bluuebunny/crossref_metadata_2025_split huggingface dataset:
Laminopathies: Involvement of structural nuclear proteins in the pathogenesis of an increasing number of human diseases
Authors: Maraldi Nadir M. , Squarzoni Stefano , Sabatelli Patrizia , Capanni Cristina , Mattioli Elisabetta , Ognibene Andrea , Lattanzi Giovanna 
Published: September 2004

AbstractJust at the beginning of the millennium the neologism laminopathies has been introduced in the scientific vocabulary. An exponential increase of interest on the subject started concomitantly, so that a formerly quite neglected group of rare human diseases is now widely investigated. This review will cover the history of the identification of the molecular basis for fourteen (since now) hereditary diseases arising from defects in genes that encode nuclear envelope and nuclear lamina‐associated proteins and will also consider the hypotheses that can account for the role of structural nuclear proteins in the pathogenesis of diseases affecting a wide spectrum of tissues. © 2004 Wiley‐Liss, Inc.
Survival versus apoptotic 17β‐estradiol effect: Role of ERα and ERβ activated non‐genomic signaling
Authors: Acconcia Filippo , Totta Pierangela , Ogawa Sumito , Cardillo Irene , Inoue Satoshi , Leone Stefano , Trentalance Anna , Muramatsu Masami , Marino Maria 
Published: September 2004

AbstractThe capability of 17β‐estradiol (E2) to induce the non‐genomic activities of its receptors (ERα and ERβ) and to evoke different signaling pathways committed to the regulation of cell proliferation has been analyzed in different cell cancer lines containing transfected (HeLa) or endogenous (HepG2, DLD1) ERα or ERβ. In these cell lines, E2 induced different effects on cell growth/apoptosis in dependence of ER isoforms present. The E2–ERα complex rapidly activated multiple signal transduction pathways (i.e., ERK/MAPK, PI3K/AKT) committed to both cell cycle progression and apoptotic cascade prevention. On the other hand, the E2–ERβ complex induced the rapid and persistent phosphorylation of p38/MAPK which, in turn, was involved in caspase‐3 activation and cleavage of poly(ADP‐ribose)polymerase, driving cells into the apoptotic cycle. In addition, the E2–ERβ complex did not activate any of the E2–ERα‐activated signal molecules involved in cell growth. Taken together, these results demonstrate the ability of ERβ isoform to activate specific signal transduction pathways starting from plasma membrane that may justify the effect of E2 in inducing cell proliferation or apoptosis in cancer cells. In particular this hormone promotes cell survival through ERα non‐genomic signaling and cell death through ERβ non‐genomic signaling. © 2004 Wiley‐Liss, Inc.
Role of cell surface heparan sulfate proteoglycans in endothelial cell migration and mechanotransduction
Authors: Moon James J. , Matsumoto Melissa , Patel Shyam , Lee Luke , Guan Jun‐Lin , Li Song 
Published: September 2004

AbstractEndothelial cell (EC) migration is critical in wound healing and angiogenesis. Fluid shear stress due to blood flow plays an important role in EC migration. However, the role of EC surface heparan sulfate proteoglycans (HSPGs) in EC adhesion, migration, and mechanotransduction is not well understood. Here, we investigated the effects of HSPG disruption on the adhesion, migration, and mechanotransduction of ECs cultured on fibronectin. We showed that disruption of HSPGs with heparinase decreased EC adhesion rate by 40% and adhesion strength by 33%. At the molecular level, HSPG disruption decreased stress fibers and the size of focal adhesions (FAs), increased filopodia formation, and enhanced EC migration. Under flow condition, heparinase treatment increased EC migration speed, but inhibited shear stress‐induced directionality of EC migration and the recruitment of phosphorylated focal adhesion kinase in the flow direction, suggesting that HSPGs are important for sensing the direction of shear stress. In addition, decreasing cell adhesion by lowering fibronectin density enhanced EC migration under static and flow condition, but did not affect the directional migration of ECs under flow. Based on our results, we propose that HSPGs play dual roles as mechanotransducer on the EC surface: (1) HSPGs–matrix interaction on the abluminal surface regulates EC migration speed through an adhesion‐dependent manner, and (2) HSPGs without binding to matrix (e.g., on the luminal surface) are involved in sensing the direction of flow through an adhesion‐independent manner. © 2004 Wiley‐Liss, Inc.
CHK1 affects cell sensitivity to microtubule‐targeted drugs
Authors: Ren Qing , Liu Ronghua , Dicker Adam , Wang Ya 
Published: September 2004

AbstractMicrotubules are the target of many anticancer drugs. Understanding the mechanism by which cells respond to different microtubule‐targeted drugs is important to resolve the drug resistance and to gain better tumor control. We report here for the first time that CHK1, an essential protein in mammalian cells, affects cell sensitivity to microtubule‐targeted drugs. By using a pair of transformed rat fibroblast cell lines, we show that compared with their counterpart B4 cells, A1‐5 cells with higher CHK1 expression are more resistant to taxotere, a microtubule stabilizer, but are more sensitive to nocodazole, a microtubule destabilizer. We also show that the altered sensitivities of A1‐5 cells to either taxotere or to nocodazole are related to the lesser microtubule‐formation in the cells. In addition, we show that the altered drug sensitivities and less microtubules‐formation shown in A1‐5 cells could be efficiently reversed by Chk1 siRNA. Taken together, these results indicate that CHK1 is one of the factors affecting cell resistance to taxotere and sensitiveness to nocodazole, suggesting that CHK1 is involved in affecting microtubule dynamics and could be inhibited for taxotere sensitization in CHK1 highly expressed tumor cells. © 2004 Wiley‐Liss, Inc.
Cell transformation byHerpesvirus saimiri
Authors: Tsygankov Alexander Y. 
Published: September 2004

AbstractHerpesvirus saimiri(Saimiriine herpesvirus‐2), a γ2‐herpesvirus (rhadinovirus) of non‐human primates, causes T‐lymphoproliferative diseases in susceptible organisms and transforms human and non‐human T lymphocytes to continuous growth in vitro in the absence of stimulation. T cells transformed byH. saimiriretain many characteristics of intact T lymphocytes, such as the sensitivity to interleukin‐2 and the ability to recognize the corresponding antigens. As a result,H. saimiriis widely used in immunobiology for immortalization of various difficult‐to‐obtain and/or ‐to‐maintain T cells in order to obtain useful experimental models. In particular,H. saimiri‐transformed human T cells are highly susceptible to infection with HIV‐1 and ‐2. This makes them a convenient tool for propagation of poorly replicating strains of HIV, including primary clinical isolates. Therefore, the mechanisms mediating transformation of T cells byH. saimiriare of considerable interest. A single transformation‐associated protein, StpA or StpB, mediates cell transformation byH. saimiristrains of group A or B, respectively. Strains of group C, which exhibit the highest oncogenic potential, have two proteins involved in transformation—StpC and Tip. Both proteins have been shown to dramatically affect signal transduction pathways leading to the activation of crucial transcription factors. This review is focused on the biological effects and molecular mechanisms of action of proteins involved inH. saimiri‐dependent transformation. © 2004 Wiley‐Liss, Inc.
Adenovirus‐mediated overexpression of tissue inhibitor of metalloproteinases‐1 in the liver: efficient protection against T‐cell lymphoma and colon carcinoma metastasis
Authors: Elezkurtaj Sefer , Kopitz Charlotte , Baker Andrew H. , Perez‐Cantó Alejandra , Arlt Matthias J. E. , Khokha Rama , Gansbacher Bernd , Anton Martina , Brand Karsten , Krüger Achim 
Published: September 2004

AbstractBackgroundMatrix metalloproteinases (MMPs) are critical for metastasis of tumor cells. Tissue inhibitor of metalloproteinases‐1 (TIMP‐1), a natural MMP inhibitor, was shown to reduce metastasis in different models. Here, we investigated whether increased TIMP‐1 levels in the liver achieved by adenoviral gene transfer will effectively inhibit liver metastasis of two independent tumor cell lines.MethodTIMP‐1 was transferred with adenoviral vectors into the livers of DBA/2 and Balb/c mice, which were subsequently challenged by hematogenous experimental metastases of the T‐cell lymphoma cell line L‐CI.5s or the colorectal carcinoma cell line CT‐26, respectively.ResultsMMP‐9 expression in the liver was induced upon metastasis in both tumor types. Adenoviral gene transfer led to high transduction efficacy as indicated by lacZ expression in 60% of hepatocytes. TIMP‐1, a key inhibitor of MMP‐9, was expressed at 105‐fold higher levels by adenoviral gene transfer as compared with levels achieved in TIMP‐1 transgenic mice, previously shown to be inefficient to reduce T‐cell lymphoma metastasis. High local and systemic (serum) levels of TIMP‐1 led to substantial (94%) reduction of T‐cell lymphoma and colorectal carcinoma (73%) experimental liver metastasis.ConclusionsAdenoviral gene transfer led to systemic and local TIMP‐1 levels sufficient to inhibit metastasis of a highly aggressive T‐cell lymphoma, pointing at the requirement of threshold levels for effective anti‐metastatic efficacy. This approach was also efficient in a colon carcinoma solid tumor model. We propose that viral gene transfer of TIMP‐1 can provide a suitable defense strategy to prevent metastatic spread to the liver. Copyright © 2004 John Wiley & Sons, Ltd.
Usefulness of the calculated apparent diffusion coefficient value in the differential diagnosis of retroperitoneal masses
Authors: Nakayama Tomohiro , Yoshimitsu Kengo , Irie Hiroyuki , Aibe Hitoshi , Tajima Tsuyoshi , Shinozaki Kenji , Nishie Akihiro , Asayama Yoshiki , Kakihara Daisuke , Matsuura Shuji , Honda Hiroshi 
Published: September 2004

AbstractPurposeTo elucidate whether or not the apparent diffusion coefficient (ADC) values calculated from echo‐planar diffusion‐weighted (EPDW) MR images are useful in the differential diagnosis of retroperitoneal masses.Materials and MethodsIn 50 patients with known retroperitoneal masses, EPDW images were performed with b‐factors of 0–1100 seconds/mm2. The final histologic diagnoses of these lesions were as follows: 12 malignant lymphomas, four other malignant mesenchymal neoplasms, 25 malignant epithelial neoplasms, seven benign mesenchymal neoplasms, and two nonneoplastic lesions. The ADC values obtained for the solid portion of the lesions were used to represent each lesion, and the values of the histologic groups were compared.ResultsThe respective value of ADC for 12 malignant lymphomas, four other mesenchymal neoplasms, seven benign mesenchymal neoplasms, and two nonneoplastic lesions were as follows: 0.66 ± 0.26, 1.26 ± 0.50, 0.90 ± 0.20, 1.87 ± 0.48, 1.32 ± 0.20 × 10−3 mm2/second. The ADC value of the malignant lymphoma was significantly lower than that of the other malignant mesenchymal lesions, and was also lower than the ADC of the benign lesions. The ADC value of the malignant epithelial neoplasms was lower than that of the benign mesenchymal tumors. The ADC values of the malignant and benign lesions were 0.94 ± 0.30 and 1.75 ± 0.49 × 10−3 mm2/second, respectively, which also demonstrated a significant difference.ConclusionADC values calculated from EPDW MR images may provide useful information in the differential diagnosis of retroperitoneal masses. J. Magn. Reson. Imaging 2004;20:735–742. © 2004 Wiley‐Liss, Inc.
Assessment of lung perfusion impairment in patients with pulmonary artery‐occlusive and chronic obstructive pulmonary diseases with noncontrast electrocardiogram‐gated fast‐spin‐echo perfusion MR imaging
Authors: Ogasawara Nobuhiko , Suga Kazuyoshi , Zaki Mohammed , Okada Munemasa , Kawakami Yasuhiko , Matsunaga Naofumi 
Published: September 2004

AbstractPurposeTo evaluate the ability of noncontrast electrocardiogram (ECG)‐gated fast‐spin‐echo (FSE) perfusion MR images for defining regional lung perfusion impairment, as compared with technetium (Tc)‐99m macroaggregated albumin (MAA) single‐photon emission computed tomography (SPECT) images.Materials and MethodsAfter acquisition of ECG‐gated multiphase FSE MR images during cardiac cycles at selected lung levels in nine healthy volunteers, 11 patients with pulmonary artery–occlusive diseases, and 15 patients with chronic obstructive pulmonary diseases (COPD), the subtracted perfusion‐weighted (PW) MR images were obtained from the two‐phase images of the minimum lung signal intensity (SI) during systole and the maximum SI during diastole, and were compared with SPECT images.ResultsECG‐gated PW images showed uniform but posture‐dependent perfusion gradient in normal lungs and visualized the various sizes of perfusion defects in affected lungs. These defect sites were nearly consistent with those on SPECT images, with a significant correlation for the affected‐to‐unaffected perfusion contrast (r = 0.753; P < 0.0001). These MR images revealed that the pulmonary arterial blood flow in the affected areas of COPD was relatively preserved as compared with pulmonary artery–occlusive diseases, and also showed significant decrease in blood flow, even in the areas with homogeneous perfusion on SPECT images in patients with focal pulmonary emphysema.ConclusionThis noninvasive MR technique allows qualitative and quantitative assessment of lung perfusion, and may better characterize regional perfusion impairment in pulmonary artery–occlusive diseases and COPD. J. Magn. Reson. Imaging 2004;20:601–611. © 2004 Wiley‐Liss, Inc.
Ferritin‐induced relaxation in tissues: An in vitro study
Authors: Gossuin Yves , Burtea Carmen , Monseux Anne , Toubeau Gérard , Roch Alain , Muller Robert N. , Gillis Pierre 
Published: September 2004

AbstractPurposeTo study in vitro the proton relaxation induced in tissues by ferritin, the iron‐storing protein of mammals.Materials and MethodsNuclear magnetic relaxation dispersion (NMRD) profiles of liver and spleen from control and iron‐overloaded mice are compared with NMRD profiles of ferritin and Fercayl®—a ferritin‐like akaganeite particle—in aqueous solutions or in 1% agarose gel.ResultsThe relaxation of water protons induced by ferritin and Fercayl® in 1% agarose gel is comparable with the relaxation of aqueous solutions of the same compounds, but slower than the relaxation of liver and spleen. The gel is not a good model of tissues containing ferritin. The longitudinal NMRD profiles of control and iron‐overloaded liver and spleen are almost identical: ferritin accumulation has only a slight effect on longitudinal relaxation. The transverse NMRD profiles of liver and spleen tissues are linear, but the slope of the linear regression is larger for iron‐loaded organs than for control ones, which is a consequence of a higher ferritin concentration in the former. However, the correlation between the slope of the transverse NMRD profiles and the iron concentration is not very good, probably because transverse relaxation is modified by the clustering of ferritin in cells.ConclusionIt could be difficult to develop a general technique for the accurate quantification of ferritin‐bound iron by nuclear magnetic resonance or magnetic resonance imaging. J. Magn. Reson. Imaging 2004;20:690–696. © 2004 Wiley‐Liss, Inc.
Prospective registration of human head magnetic resonance images for reproducible slice positioning using localizer images
Authors: Gedat Egbert , Braun Juergen , Sack Ingolf , Bernarding Johannes 
Published: September 2004

AbstractPurposeTo facilitate assessing brain tumor growth and progression of stroke lesions by reproducible slice positioning in human head magnetic resonance (MR) images, a method for prospective registration is proposed that adjusts the image slice position without moving the patient and with no additional scans.Materials and MethodsThe gradient reference frame of follow‐up examinations was adjusted to achieve the same image slice positioning relative to the patient as in the previous examination. The three‐dimensional geometrical transformation parameters for the gradients were determined using two‐dimensional image registration of three orthogonal localizer images. The method was developed and evaluated using a phantom with arbitrarily adjustable position. Feasibility for in vivo applications was demonstrated with brain MR imaging (MRI) of healthy volunteers.ResultsStandard retrospective registration was used for assessing the quality of the method. The accuracy of the realignment was 0.0 mm ± 1.2 mm and –0.2° ± 0.9° (mean ± SD) in phantom experiments. In 10 examinations of volunteers, misalignments up to 49.2 mm and 21° were corrected. The accuracy of the realignment after prospective registration was 0.1 mm ± 1.5 mm and 0.2° ± 1.5°.ConclusionImage‐based prospective registration using localizer images of the pre‐ and postexaminations is a robust method for reproducible slice positioning. J. Magn. Reson. Imaging 2004;20:581–587. © 2004 Wiley‐Liss, Inc.
Functional MRI of the lung using hyperpolarized 3‐helium gas
Authors: van Beek Edwin J.R. , Wild Jim M. , Kauczor Hans‐Ulrich , Schreiber Wolfgang , Mugler John P. , de Lange Eduard E. 
Published: September 2004

AbstractLung imaging has traditionally relied on x‐ray methods, since proton MRI is limited to some extent by low proton density in the lung parenchyma and static field inhomogeneities in the chest. The relatively recent introduction of MRI of hyperpolarized noble gases has led to a rapidly evolving field of pulmonary MRI, revealing functional information of the lungs, which were hitherto unattainable. This review article briefly describes the physical background of the technology, and subsequently focuses on its clinical applications. Four different techniques that have been used in various human investigations are discussed: ventilation distribution, ventilation dynamics, and small airway evaluation using diffusion imaging and oxygen uptake assessment. J. Magn. Reson. Imaging 2004;20:540–554. © 2004 Wiley‐Liss, Inc.
Resolution improvement in thick‐slab magnetic resonance digital subtraction angiography using SENSE at 3T
Authors: Summers Paul E. , Kollias Spyros S. , Valavanis Anton 
Published: September 2004

AbstractPurposeTo evaluate the use of parallel imaging (sensitivity encoding [SENSE]) to improve spatial resolution and achieve sub‐second temporal resolution in fluoroscopic contrast‐enhanced, magnetic resonance digital subtraction angiography (MR‐DSA).Materials and MethodsA MR‐DSA sequence was optimized on a 3‐T scanner with respect to sampling bandwidth and SENSE acceleration factor subject to the constraints of half‐second acquisition time and 0.6 × 1.2 mm in‐plane resolution. MR‐DSA with and without SENSE acceleration was then evaluated in patients with arterio‐venous malformations (AVMs).ResultsConsistent with previously reported results and theory, SENSE factors greater than two and increasing sampling bandwidth both led to increasing image noise. Compared to lower resolution MR‐DSA images with similar temporal resolution, the SENSE accelerated sequence provided better spatial resolution without notable changes in the contrast enhancement of the vascular territories of the AVMs but was hampered somewhat in the late venous phases by a reconstruction artifact.ConclusionSENSE acceleration of MR‐DSA by a factor of two allows improved temporal or spatial resolution without significant loss of image quality. Signal‐to‐noise degradation associated with higher SENSE acceleration factors are likely to necessitate other approaches to further improving resolution in MR‐DSA. Clinically, SENSE accelerated MR‐DSA improves the non‐invasive pre‐ and postoperative depiction of AVM flow dynamics. J. Magn. Reson. Imaging 2004;20:662–673. © 2004 Wiley‐Liss, Inc.
Endorectal diffusion‐weighted imaging in prostate cancer to differentiate malignant and benign peripheral zone tissue
Authors: Hosseinzadeh Keyanoosh , Schwarz Samuel David 
Published: September 2004

AbstractPurposeTo determine if the apparent diffusion coefficient (ADC) can discriminate benign from malignant peripheral zone (PZ) tissue in patients with biopsy‐proven prostate cancer that have undergone endorectal diffusion‐weighted imaging (DWI) of the prostate.Materials and MethodsTen patients with prostate cancer underwent endorectal magnetic resonance imaging (MRI) in addition to DWI. A two‐dimensional grid was placed over the axial images, and each voxel was graded by a 4‐point rating scale to discriminate nonmalignant from malignant PZ tissue based on MR images alone. ADC was then determined for each voxel and plotted for nonmalignant and malignant voxels for the entire patient set. Second, with the radiologist aware of biopsy locations, any previously assigned voxel grade that was inconsistent with biopsy data was regrouped and ADCs were replotted.ResultsFor the entire patient set, without and with knowledge of the biopsy data, the mean ADCs for nonmalignant and malignant tissue were 1.61 ± 0.27 and 1.34 ± 0.38 × 10−3 mm2/second (P = 0.002) and 1.61 ± 0.26 and 1.27 ± 0.37 × 10−3 mm2/second (P = 0.0005), respectively.ConclusionDWI of the prostate is possible with an endorectal coil. The mean ADC for malignant PZ tissue is less than nonmalignant tissue, although there is overlap in individual values. J. Magn. Reson. Imaging 2004;20:654–661. © 2004 Wiley‐Liss, Inc.
A STAP algorithm approach to fMRI: A simulation study
Authors: Thompson Elizabeth A. , Holland Scott K. , Schmithorst Vincent J. 
Published: September 2004

AbstractPurposeTo adapt the space‐time adaptive processing (STAP) algorithm, previously developed in the field of sensor array processing and applied to radar signal processing, for use in construction of brain activation maps in functional magnetic resonance imaging (fMRI).Materials and MethodsSTAP is a two‐dimensional filter in which both the spatial and temporal responses are controlled adaptively. It processes space‐time data as a complete spatiotemporal set. Unlike presently used fMRI techniques, STAP locates activated regions both spatially and in frequency.ResultsComputer simulations incorporating actual MRI noise indicate that STAP exhibits a high degree of accuracy in detecting the small signal intensity changes inherent in fMRI.ConclusionBecause STAP processes space‐time data as a single data matrix, it exhibits potential over currently available fMRI methods in providing a measure of the full spatiotemporal extent of a task‐related activity. J. Magn. Reson. Imaging 2004;20:715–722. © 2004 Wiley‐Liss, Inc.
Algorithms for calculation of kinetic parameters from T1‐weighted dynamic contrast‐enhanced magnetic resonance imaging
Authors: Horsfield Mark A. , Morgan Bruno 
Published: September 2004

AbstractPurposeTo quantify the errors involved in calculating dynamic parameters (Ktrans and ve) from dynamic contrast‐enhanced magnetic resonance imaging (DCE‐MRI) scans, and to develop alternative analyses to improve accuracy or increase processing speed.Materials and MethodsThis paper presents three different ways of handling the discrete samples of the arterial input and tissue response data with increasing fidelity, with which this continuous arterial input function (AIF) is represented. Also, a new noniterative approach to parameter estimation was developed from one used previously for analysis of radioactive tracer concentrations in radioangiography. The analysis methods were tested using simulated data.ResultsThe more sophisticated schemes for data processing give more accurate parameter estimates when data are sparsely sampled, at least for the AIF that we modeled. The noniterative algorithm is very rapid in execution, but was more susceptible to measurement errors.ConclusionThe improved algorithms presented should be useful when the AIF and tissue response are sparsely sampled. The noniterative approach may be suitable for semiquantitative visualization, or where the AIF and tissue response are sampled accurately and with a small time interval between samples. J. Magn. Reson. Imaging 2004;20:723–729. © 2004 Wiley‐Liss, Inc.