bluuebunny/crossref_metadata_2025_split huggingface dataset:
Borna disease virus‐induced accumulation of macrophage migration inhibitory factor in rat brain astrocytes is associated with inhibition of macrophage infiltration
Authors: Bacher Michael , Weihe Eberhard , Dietzschold Bernhard , Meinhardt Andreas , Vedder Helmut , Gemsa Diethard , Bette Michael 
Published: October 2004

AbstractTo test the hypothesis that macrophage migration inhibitory factor (MIF) plays a role in macrophage invasion during virus‐induced encephalitis, we analyzed the expression and cellular localization of MIF in the Borna disease virus (BDV)‐infected rat brain, monitored monocyte/macrophage infiltration, and evaluated the influence of anti‐inflammatory treatment with dexamethasone. MIF mRNA expression was restricted to neurons and remained unchanged after BDV infection or after dexamethasone treatment of either BDV‐infected or uninfected control rats. In contrast, MIF protein immunoreactivity (ir) was not only seen in neurons but also in glia. After BDV‐induced encephalitis and treatment of uninfected rats with dexamethasone, MIF ir was only slightly altered in neurons but moderately enhanced in tanycytes, ependyma, and choroid plexus epithelium and markedly increased or induced in astrocyte end‐feet at the blood‐brain barrier (BBB). The increase in MIF ir in astrocytes after BDV infection was blocked by dexamethasone. The induction or enhancement of MIF ir at the BBB significantly correlated with reduced numbers of infiltrating ED1‐positive monocytes/macrophages after BDV infection. Increased macrophage invasion was observed in regions where no astrocytic MIF was detected. The BDV‐ or dexamethasone‐induced accumulation of MIF protein in astrocytes in vivo in absence of detectable astrocytic MIF mRNA expression is most likely due to MIF translocation from neurons rather than to a constitutive or induced MIF mRNA expression in astrocytes. In conclusion, we provide evidence that translocation of MIF from neurons or other extracellular sources into astrocytes is likely to modulate the inflammatory process during the course of virus‐induced encephalitis by limiting monocyte/macrophage migration through the BBB. GLIA 37:291–306, 2002. © 2002 Wiley‐Liss, Inc.
Juxtavascular microglia migrate along brain microvessels following activation during early postnatal development
Authors: Grossmann Ruth , Stence Nick , Carr Jenny , Fuller Leah , Waite Marc , Dailey Michael E. 
Published: October 2004

AbstractSome parenchymal microglia in mammalian brain tissues, termed “juxtavascular microglia,” directly contact the basal lamina of blood vessels; however, the functional consequences of this unique structural relationship are unknown. Here we used a rat brain slice model of traumatic brain injury to investigate the dynamic behavior of juxtavascular microglia following activation. Juxtavascular microglia were identified by confocal 3D reconstruction in tissue slices stained with a fluorescent lectin (FITC‐IB4) that labels both microglia and blood vessel endothelial cells. Immunolabeling confirmed that juxtavascular cells were true parenchymal microglia (OX42+, ED2−) and not perivascular cells or pericytes. Time‐lapse imaging in live tissue slices revealed that activating juxtavascular microglia withdraw most extant branches but often maintain contact with blood vessels, usually moving to the surface of a vessel within 1–4 h. Subsequently, some microglia migrate along the parenchymal surface of vessels, moving at rates up to 40 μm/h. Activated juxtavascular microglia sometimes repeatedly extend veil‐like protrusions into the surrounding tissue, consistent with a role in tissue surveillance. Juxtavascular cells were twice as likely as nonjuxtavascular cells to be locomotory by 10 h in vitro, suggesting an enhanced activation response. Moreover, 38% of all juxtavascular cells migrated along a vessel, whereas this was never observed for a nonjuxtavascular cell. These observations identify a mobile subpopulation (10%–30%) of parenchymal microglia that activate rapidly and are preferentially recruited to the surfaces of blood vessels following brain tissue injury. The dynamic and sustained interaction of microglia with brain microvessels may facilitate signaling between injured brain parenchyma and components of the blood‐brain barrier or circulating immune cells of the blood in vivo. GLIA 37:229–240, 2002. © 2002 Wiley‐Liss, Inc.
Preparation of a monoclonal antibody to citrullinated epitopes: Its characterization and some applications to immunohistochemistry in human brain
Authors: Nicholas Anthony P. , Whitaker John N. 
Published: October 2004

AbstractUsing hybridoma technology, an IgM monoclonal antibody (mAb), designated as F95, was developed against a deca‐citrullinated peptide (DCP) consisting of 10 citrulline residues and a carboxyl Gly‐Gly‐Cys through which DCP was covalently linked to an activated carrier protein, keyhole limpet hemocyanin (KLH). Clones were selected on the basis of not reacting with human unmodified and noncitrullinated myelin basic protein (MBP), MBP‐C1, but reacting well with human citrullinated MBP (MBP‐C8). When tested by ELISA, this mAb demonstrated minimal reactivity with human MBP‐C1, varying reactivity with the C2–C5 isomers of human MBP, moderate binding with guinea pig MBP‐C8, and strong reactivity with human MBP‐C8. By ELISA, mAb F95 was directed predominantly against citrulline, not MBP, as revealed by its binding to DCP linked with activated KLH, bovine serum albumin (BSA), or ovalbumin (OA), but not with KLH, BSA, or OA alone. Immunohistochemistry of normal human brain demonstrated that F95 stained central nervous system myelin and a subset of astrocytes. Given the citrulline‐directed features of mAb F95, this immunohistochemical pattern suggests that certain astroglial filaments expressing glial fibrillary acidic protein also contain citrulline‐bearing components. These potentially implicate citrullinated proteins, notably in astroglial filaments, in a variety of normal and pathological neurobiological processes. GLIA 37:328–336, 2002. © 2002 Wiley‐Liss, Inc.
Anatomically informed basis functions in multisubject studies
Authors: Kiebel Stefan , Friston Karl J. 
Published: October 2004

AbstractWe describe the use of anatomically informed basis functions (AIBF) in the analysis of multisubject functional imaging studies. AIBF are used to specify an anatomically informed spatial model that embodies anatomical knowledge for the statistical analysis of neuroimaging data. In a previous communication, we showed how AIBF can be used to incorporate prior anatomical constraints in single subject functional magnetic resonance image (fMRI) analyses to augment their anatomical precision. In this paper, we extend AIBF such that it can be applied to multisubject studies using fMRI or PET. The key concept is that, after spatial normalization, a canonical cortical surface can be used to generate a forward model of signal sources for all subjects. By estimating the hemodynamic signal in this canonical AIBF‐space and then projecting it back into the voxel‐space, one effectively extracts functional activity that is smooth, within and only within, the cortical sheet while attenuating other components unrelated to the physiological process of interest. The ensuing procedure can be considered as a highly non‐stationary, anisotropic anatomically informed [de]convolution or smoothing. It is shown that this procedure offers various advantages compared to existing conventional methods for the analysis of multisubject studies, in particular it is more sensitive to underlying activations. Hum. Brain Mapping 16:36–46, 2002. © 2002 Wiley‐Liss, Inc.
Simultaneous measurements of cerebral oxygenation changes during brain activation by near‐infrared spectroscopy and functional magnetic resonance imaging in healthy young and elderly subjects
Authors: Mehagnoul‐Schipper D. Jannet , van der Kallen Bas F.W. , Colier Willy N.J.M. , van der Sluijs Marco C. , van Erning Leon J.Th.O. , Thijssen Henk O.M. , Oeseburg Berend , Hoefnagels Willibrord H.L. , Jansen René W.M.M. 
Published: October 2004

AbstractNear infrared spectroscopy (NIRS) and functional magnetic resonance imaging (fMRI) both allow non‐invasive monitoring of cerebral cortical oxygenation responses to various stimuli. To compare these methods in elderly subjects and to determine the effect of age on cortical oxygenation responses, we determined motor‐task‐related changes in deoxyhemoglobin concentration ([HHb]) over the left motor cortex in six healthy young subjects (age 35 ± 9 years, mean ± SD) and five healthy elderly subjects (age 73 ± 3 years) by NIRS and blood‐oxygen‐level‐dependent (BOLD) fMRI simultaneously. The motor‐task consisted of seven cycles of 20‐sec periods of contralateral finger‐tapping at a rate as fast as possible alternated with 40‐sec periods of rest. Time‐locked averages over the seven cycles were used for further analysis. Task‐related decreases in [HHb] over the motor cortex were measured by NIRS, with maximum changes of −0.83 ± 0.38 μmol/L (P < 0.01) for the young and −0.32 ± 0.17 μmol/L (P < 0.05) for the elderly subjects. The BOLD‐fMRI signal increased over the cortex volume under investigation with NIRS, with maximum changes of 2.11 ± 0.72% (P < 0.01) for the young and 1.75 ± 0.71% (P < 0.01) for the elderly subjects. NIRS and BOLD‐fMRI measurements showed good correlation in the young (r = −0.70, r2 = 0.48, P < 0.001) and elderly subjects (r = −0.82, r2 = 0.67, P < 0.001). Additionally, NIRS measurements demonstrated age‐dependent decreases in task‐related cerebral oxygenation responses (P < 0.05), whereas fMRI measurements demonstrated smaller areas of cortical activation in the elderly subjects (P < 0.05). These findings demonstrate that NIRS and fMRI similarly assess cortical oxygenation changes in young subjects and also in elderly subjects. In addition, cortical oxygenation responses to brain activation alter with aging. Hum. Brain Mapping 16:14–23, 2002. © 2002 Wiley‐Liss, Inc.
Prediction of survival in patients with head and neck cancer using the histoculture drug response assay
Authors: Singh Bhuvanesh , Li Rongou , Xu Li , Poluri Ashok , Patel Snehal , Shaha Ashok R. , Pfister David , Sherman Eric , Goberdhan Andy , Hoffman Robert M. , Shah Jatin 
Published: October 2004

AbstractBackgroundChemoresponse is a significant outcome predictor in patients with head and neck cancer, regardless of the treatment modality used. The histoculture drug response assay (HDRA) has been shown to be a reliable method for in vitro chemoresponse assessment. In this study, we have correlated the HDRA assessment with survival in patients with head and neck squamous cell carcinoma (HNSCC).MethodTumor specimens from 41 of 42 patients undergoing treatment for HNSCC were successfully evaluated by the HDRA. Tumor tissue was histocultured on Gelfoam sponges gel in 24‐well plates, followed by treatment with cisplatin (15 μg/mL) or 5‐fluorouracil (40 μg/mL) in triplicate. A control group received no drug treatment. After completion of drug treatment, the relative cell survival in the tumors was determined using the MTT assay. The inhibition rate (IR) for each drug was calculated relative to the control for each case, and sensitivity was defined as a tumor IR of greater than 30%. Treatment was based on established protocols for the location and stage of the tumor and included surgery, radiation, and/or chemotherapy. Survival comparisons were performed using the generalized Wilcoxon test for the comparison of Kaplan‐Meier survival curves.ResultsResistance to 5‐fluorouracil was present in 13 cases (32%), to cisplatinum in 13 cases (32%), and to both agents in 11 cases (27%). The 2‐year cause‐specific survival was significantly greater for patients sensitive to 5‐fluorouracil (85% vs 64%; p = .04), cisplatinum (86% vs 64%; p = .05), or both agents (85% vs 63%; p = .01). The association between HDRA assessment of chemoresponse and clinical outcome remained significant even after controlling for the effects of TNM stage and the presence of recurrent cancer at presentation by multivariate analysis.ConclusionsChemosensitivity determined by the HDRA seems to be a strong predictor of survival in patients with advanced HNSCC and should be considered further. © 2002 Wiley Periodicals, Inc.
Role of planned neck dissection for advanced metastatic disease in tongue base or tonsil squamous cell carcinoma treated with radiotherapy
Authors: Roy Saswata , Tibesar Robert J. , Daly Kathleen , Pambucian Stephan , Lee H. K. , Gapany Markus , Adams George L. 
Published: October 2004

AbstractObjectiveAt the conclusion of this article, the reader should be able to discuss the need for planned neck dissection for advanced cervical diseases in the tongue base and tonsil cancer after treatment with radiotherapy.BackgroundIn the past 5 years, we have treated patients with squamous cell carcinoma of the tonsil and tongue base with radiotherapy as the primary therapeutic modality. A planned complete neck dissection was performed on all patients with N2 or greater cervical disease regardless of response to radiotherapy. Composite resection was performed when there was persistent disease at the primary site. Although the “radiation‐first” therapeutic approach for tongue base and tonsil cancer is widely accepted, the planned neck dissection for neck metastases remans controversial. The objective of the study was to determine the validity of planned neck dissection after radiotherapy for N2 disease.MethodsMedical records of patients with primary squamous cell carcinoma of the tongue base and tonsil with neck metastasis staged N2 or greater were reviewed. Between 1994 and 1999, 36 such patients were treated with curative radiation therapy. Response was assessed 6 to 8 weeks after completion of treatment with clinical examination and CT imaging. All patients underwent planned neck dissection. We reviewed the clinical and radiographic response of neck disease to radiotherapy as it correlated with the histopathologic findings.ResultsOf the 36 patients, 17 had clinical and CT evidence of persistent disease. In this group, 65% had pathologically confirmed diseases at surgery. Of the 9 patients with no evidence of disease on clinical examination, negative biopsy at the primary site, and a negative CT scan, 33% (three of nine) still had residual disease in the neck dissection specimen.ConclusionsPositive findings on clinical examination and CT can predict the presence of malignancy after radiation therapy. However, a negative CT and clinical examination are limited in predicting a complete response. These data lend support to the role of planned neck dissection after radiotherapy of N2 neck disease. © 2002 Wiley Periodicals, Inc.
Histopathologic reaction of a calcium phosphate cement for alveolar ridge augmentation
Authors: Sugawara Akiyoshi , Fujikawa Kenji , Kusama Kaoru , Nishiyama Minoru , Murai Seidai , Takagi Shozo , Chow Laurence C. 
Published: October 2004

AbstractThe objective of the present study was to evaluate the feasibility of using a calcium phosphate cement (CPC) in the reconstruction of a defective alveolar ridge in conjunction with implant placement. The CPC consisted of an equimolar amount of tetracalcium phosphate and dicalcium phosphate anhydrous. At the beginning of the experiment, all mandibular premolar teeth of mature beagle dogs were extracted. After 1 month of healing, alveolar bone was reduced to make a space for a CPC block that was prefabricated from a CPC mixed with water at a powder/liquid ratio of 5 g/mL. After an additional month, 8‐mm long hydroxyapatite‐coated titanium implants were placed in such a way that the apical half was embedded into alveolar bone and the coronal half in the preformed CPC block. The dogs were sacrificed and biopsies were obtained at 1, 3, and 6 months after surgery. Sections that included implants were evaluated for integration of the CPC block to the alveolar bone and of the implant to the alveolar bone. Additional sections without the implants served as controls. The results obtained from this study show that the CPC ridge augmentation gradually is replaced by natural bone. Six months after surgery, histopathologic features of the augmentation area were quite similar to those of natural alveolar bone. The coronal half of the implants, previously surrounded by the CPC block, was firmly fixed by natural bone. Therefore, this method may be useful for increasing the height of the alveolar ridge. © 2002 Wiley Periodicals, Inc. J Biomed Mater Res 61: 47–52, 2002
Synthesis of macroporous hydroxyapatite scaffolds for bone tissue engineering
Authors: Li Shi Hong , De Wijn Joost R. , Layrolle Pierre , De Groot Klaas 
Published: October 2004

AbstractA novel method of preparing macroporous hydroxyapatite (HA) by dual‐phase mixing was developed: HA slurry and Polymethylmethacrylate (PMMA) resin were mixed together at the volume ratio of 1:1. After pyrolytic removal of the PMMA phase, HA with an open porous structure was obtained. In this way, the porosity of the ceramic was limited to 50%. Attempts to increase the porosity by adding more PMMA resin were confronted with the technical hurdle of sample collapse during the pyrolysis process. To increase the porosity and to improve pore interconnection, an extra foaming step was introduced before the polymerization of PMMA resin. Three foaming agent systems were tried, based on the reactions of citric acid and (bi)carbonate salts: sodium bicarbonate, calcium carbonate, and ammonium bicarbonate. Although all the three foaming agents were able to increase the porosity up to 70%, keeping all the pores interconnected throughout, only ammonium bicarbonate system turned out to be applicable to make HA scaffolds or implants, because both NaHCO3 and CaCO3 systems caused alkalic residues in the final ceramic. The porous HA samples were fully characterized by FTIR, XRD, ESEM (EDX), and optical microscopy. © 2002 Wiley Periodicals, Inc. J Biomed Mater Res 61: 109–120, 2002
Liquid photocurable biodegradable copolymers: In vivo degradation of photocured poly(ϵ‐caprolactone‐co‐trimethylene carbonate)
Authors: Mizutani Manabu , Matsuda Takehisa 
Published: October 2004

AbstractLiquid photoreactive poly(ϵ‐caprolactone‐co‐trimethylene carbonate)s endcapped with a coumarin group [coumarinated poly(CL/TMC)s] were prepared using tetra‐functional hydroxylated substances such as pentaerythritol or four‐branched poly(ethylene glycol), b‐PEG. These coumarinated copolymers are tetra‐branched and exist as a viscous liquid (MW 5 ×103∼7 × 103). They were photocured by ultraviolet (UV) light irradiation to obtain a swelling or nonswelling solid under water, depending on the type of initiator used. The resultant films were implanted into the subcutaneous tissues of rats for up to 5 months. The photocured b‐PEG‐based copolymer was completely degraded and sorbed within a 1 month. On the other hand, surface‐eroding degradation of pentaerythritol‐based, coumarinated poly(CL/TMC) progressed with implantation time, and minimal recruitment of neutrophils, macrophages, and multinucleated giant cells was observed over the implantation period. Among the pentaerythritol‐based copolymers, the fastest surface erosion was observed for the copolymer with the highest ϵ‐caprolactone content. Microfabricated films with microarrays in which photoconstructs were stereolithographically prepared, using three different coumarinated copolymers at different regions, showed that upon implantation there was regionally differentiated biodegradation of microarrays, and the degree of region‐specific biodegradation depended on the type of photocured copolymer. The observed tendency for biodegradation was in good agreement with that observed during implantation of individual films in vivo. This study also demonstrates that the use of multi‐material‐arrayed films enables the determination of different responses in vivo using only one sample. © 2002 Wiley Periodicals, Inc. J Biomed Mater Res 61: 53–60, 2002
Soft‐tissue response to silicone and poly‐L‐lactic acid implants with a periodic or random surface micropattern
Authors: Parker J. A. T. C. , Walboomers X. F. , Von den Hoff J. W. , Maltha J. C. , Jansen J. A. 
Published: October 2004

AbstractTissue reaction to biomaterials is dependent on properties such as surface topography. The aim of this study was to evaluate the tissue reaction around implants with different surface topographies. We made coin‐shaped silicone and poly‐L‐lactic acid (PLLA) implants with double‐sided parallel microgrooves (depth 1.0 μm; width 10.0 μm) and random roughness on a micrometer scale. The control implants were smooth. These implants were inserted into subcutaneous pockets created on the flanks of goats. After 1, 3, or 12 weeks, the goats were sacrificed and the implants retrieved and histologically processed. Light microscopic evaluation revealed the formation of fibrous tissue capsules around all implant materials. The PLLA did not visibly degrade during the study period. Histomorphometric analyses were performed on capsule thickness, capsule quality, and on the implant–tissue interface quality. Compared with the silicone implants, the capsules around the PLLA implants showed significantly better capsule quality. Compared to the smooth implants, the capsules around the microgrooved implants were thicker, but the capsules around the roughened implants were thinner. However, randomly roughened implant surfaces generally elicited a stronger and more prolonged inflammatory reaction compared to smooth and microgrooved implant surfaces. We conclude that the application of microgrooves or random surface roughness to polymer implants apparently does not have beneficial effects on peri‐implant tissue healing. © 2002 Wiley Periodicals, Inc. J Biomed Mater Res 61: 91–98, 2002
Calcium oscillations in Xenopus egg cycling extracts
Authors: Tokmakov Alexander A. , Sato Ken‐Ichi , Fukami Yasuo 
Published: October 2004

AbstractCell cycle in various types of cells and in early embryos is often accompanied by transient changes in the concentration of free cytosolic calcium. In the present study, using fluorescent indicator fura‐2, we demonstrate that Ca2+ oscillates cyclically with an amplitude of about 100 nM and a period of mitotic cycle in cell‐free Xenopus egg cycling extracts. It peaks in early metaphase just preceding mitotic reactivation of Cdc2 kinase and MAPK and reaches a minimum in interphase. The source of Ca2+ in the extracts is a particulate fraction containing egg intracellular Ca2+ stores, since the addition of a calcium‐mobilizing second messenger, inositol 1,4,5‐trisphosphate (IP3), induced a transient increase in Ca2+. The inclusion of heparin, an IP3 receptor antagonist, or ultrafiltration of the extracts prevented Ca2+‐releasing activity of IP3. The depletion of Ca2+ in the extracts by the calcium chelator BAPTA resulted in the blockade of cell cycle at different stages, depending on the time of drug administration. The addition of BAPTA late in interphase blocked cell cycle at mitotic entry in prophase, whereas its application in anaphase or telophase blocked the extracts in early interphase. BAPTA administration in metaphase before transition to anaphase brought about a metaphase‐like arrest in the cycling extracts. Inhibition of IP3‐induced calcium release by heparin also arrested cell cycle progression in the cycling extracts. J. Cell. Biochem. 82: 89–97, 2001. © 2001 Wiley‐Liss, Inc.