bluuebunny/crossref_metadata_2025_split huggingface dataset:
Postcontrast Susceptibility-Weighted Imaging
Authors: Jagadeesan Bharathi D. , Delgado Almandoz Josser E. , Benzinger Tammie L.S. , Moran Christopher J. 
Published: September 2011

Background and Purpose—
The purpose of this study was to determine the utility of postcontrast susceptibility-weighted MRI (PCSWI) in the evaluation of vascular malformations of the brain (BVM).

Methods—
We retrospectively evaluated PCSWI and digital subtraction angiography data from 16 consecutive patients with known or suspected BVM, which had been entered into a prospectively maintained database during a 1-year period. There had been no intervening treatment or change in patients' symptoms between the PCSWI and digital subtraction angiography studies. The use of PCSWI in the detection of arteriovenous shunting was compared with that of routine noncontrast susceptibility-weighted imaging, time-of-flight MR angiography, and contrast-enhanced MR angiography using digital subtraction angiography results as the reference standard. The presence of arteriovenous shunting in PCSWI or susceptibility-weighted imaging sequences was defined by the presence of abnormal signal hyperintensity in the venous structures adjacent to the BVM.

Results—
A total of 17 BVMs were identified by digital subtraction angiography (9 newly diagnosed arteriovenous malformations, 3 dural arteriovenous fistulas, 4 treated arteriovenous malformations with residual arteriovenous shunting, and 1 complex developmental venous anomaly). PCSWI was 100% sensitive and 100% specific with 100% positive predictive value and 100% negative predictive value for the detection of arteriovenous shunting in these BVMs. The PCSWI/susceptibility-weighted imaging signal intensity ratio in the most prominent early draining venous structure was 1.2±0.32.

Conclusions—
PCSWI appears to be superior to susceptibility-weighted imaging, time-of-flight MR angiography, and contrast-enhanced MR angiography in detecting arteriovenous shunting in BVMs and may be useful in the initial diagnosis and follow-up of patients with BVMs.
Vertebral Artery Halo Sign in Patients With Stroke
Authors: García-García Jorge , Ayo-Martín Óscar , Argandoña-Palacios Lucía , Segura Tomas 
Published: September 2011

Background and Purpose—
The purpose of this study was to describe typical ultrasonographic findings of vertebral arteries in patients affected by giant cell arteritis.

Methods—
Color duplex sonography was used to asses the cervical arteries within 24 hours from stroke onset in 1237 patients. Vertebral arteritis was considered if concentric, homogeneous, and smooth hypoechogenic mural thickening (the so-called halo sign) was present in at least 1 cervical segment of the vertebral artery. If the patient showed such findings, an ultrasound examination of the temporal artery was also performed. Patients with probable giant cell arteritis were treated with high-dose intravenous methylprednisolone in association with antiplatelet therapy. Temporal artery biopsy was carried out by a vascular surgeon in the site targeted by the ultrasonographer.

Results—
Five patients were diagnosed as having vertebral arteritis according to ultrasound criteria. All of them had initial neurological deficit due to infarctions affecting the vertebrobasilar territory. One patient died due to aspiration pneumonia, whereas the others were independent at discharge. All patients had a positive biopsy for giant cell arteritis.

Conclusions—
Vertebral artery involvement in giant cell arteritis may be suspected by color duplex sonography. This fact would allow a prompt diagnosis and treatment of this otherwise fatal disease. Because duplex ultrasonography is a usual test performed on patients with stroke, the recognition of the halo sign in vertebral arteries may be of crucial interest in selected cases.
Telomerase Reverse Transcriptase Upregulation Attenuates Astrocyte Proliferation and Promotes Neuronal Survival in the Hypoxic–Ischemic Rat Brain
Authors: Qu Yi , Duan Zhoujin , Zhao Fengyan , Wei Dapeng , Zhang Jianbo , Tang Binzhi , Li Jiao , Yang Chunlei , Mu Dezhi 
Published: September 2011

Background and Purpose—
Telomerase reverse transcriptase (TERT) is tightly related to the resistance of cells to stress and injury. However, little is known about the roles of TERT in the nervous system. We try to investigate the effects of TERT on the function of astrocytes in developing rat brains subjected to hypoxia–ischemia.

Methods—
TERT expression was detected in rat brains with hypoxia–ischemia. In in vitro study, the function of astrocytes with TERT overexpression was measured, and the effects of astrocyte on neuronal apoptosis were examined. Moreover, overexpression or inhibition of TERT was conducted in vivo by gene transduction. Astrocyte proliferation was examined through Ki67 staining. Terminal deoxynucleotidyltransferase-mediated dUTP nick end labeling staining and brain infarct volume calculation were used to detect neuronal injury.

Results—
Both TERT mRNA and protein were upregulated in neurons within 2 days but shifted to astrocytes at Day 3 after hypoxia–ischemia. Astrocyte proliferation was inhibited with TERT overexpression due to the upregulation of cell-cycle regulatory protein p15. Meanwhile, the apoptosis of neurons increased, whereas neurons were cocultured with conditioned media from astrocytes with TERT inhibition compared with TERT overexpression due to the decrease of neurotrophin-3 expression in astrocytes. Furthermore, Ki67-positive astrocytes and neuronal injury were found to be inhibited in TERT-overexpressing rat brains with hypoxia–ischemia.

Conclusions—
TERT attenuates astrocyte proliferation and promotes neuronal survival in the developing rat brain after hypoxia–ischemia, partly through its enhancement of p15 and neurotrophin-3 expression in astrocytes.
Adverse Effects of Bone Marrow Stromal Cell Treatment of Stroke in Diabetic Rats
Authors: Chen Jieli , Ye Xinchun , Yan Tao , Zhang Chunling , Yang Xiao-Ping , Cui Xu , Cui Yishen , Zacharek Alex , Roberts Cynthia , Liu Xinfeng , Dai Xiangguo , Lu Mei , Chopp Michael 
Published: September 2011

Background and Purpose—
Cell therapy with bone marrow stromal cells (BMSCs) improves functional recovery after stroke in nondiabetic rats. However, its effect on diabetics with stroke is unknown. This study investigated the effect of BMSCs on stroke outcome in Type 1 diabetic (T1DM) rats.

Methods—

T1DM was induced in adult male Wistar rats by injecting streptozotocin. Nondiabetic and T1DM rats were subjected to 2 hours of middle cerebral artery occlusion (MCAO), treated with or without BMSCs (3×10
6
) at 24 hours after MCAO, and monitored for 14 days.

Results—

Functional benefit was not detected in T1DM-MCAO treated with BMSC rats compared with corresponding T1DM-MCAO controls. BMSC treatment in T1DM-MCAO rats had increased mortality, blood–brain barrier leakage, brain hemorrhage, and angiogenesis. Internal carotid artery neointimal formation and cerebral arteriole narrowing/occlusion were also observed in T1DM-MCAO+BMSCs rats compared with T1DM-MCAO controls (
P
<0.05), but not in nondiabetic stroke rats. We further studied the underlying mechanisms responsible for BMSC-induced blood–brain barrier leakage and accelerated vascular damage in T1DM-MCAO rats. We found that the expression of angiogenin (an angiogenic factor) and ED1 (a marker for macrophages) was significantly increased in the T1DM-MCAO+BMSC rats in the ischemic brain and internal carotid artery compared with nontreated T1DM-MCAO rats, but not in nondiabetic stroke rats.

Conclusions—
BMSC therapy in T1DM-MCAO rats does not improve functional outcome. On the contrary, it increases blood–brain barrier leakage and cerebral artery neointimal formation, and arteriosclerosis, which possibly is due to increased expression of angiogenin. Thus, BMSC treatment starting 24 hours after MCAO may not be beneficial for diabetic subjects with stroke.
The Global Atmospheric Circulation Response to Tropical Diabatic Heating Associated with the Madden–Julian Oscillation during Northern Winter
Authors: Seo Kyong-Hwan , Son Seok-Woo 
Published: September 2011

Abstract
The detailed dynamical mechanisms of the upper-tropospheric circulation response to the Madden–Julian oscillation (MJO) convection are examined by integrating a primitive equation model. A series of initial-value calculations with the climatological boreal winter background flow forced by the MJO-like thermal forcing successfully capture the key aspects of the observed circulation response to the MJO convection. This suggests that a large fraction of MJO-related circulation anomalies are direct responses to tropical heating in both the tropics and extratropics and can be largely explained by linear dynamics.
It is found that MJO-like dipole heatings not only intensify tropical upper-tropospheric anomalies but also weaken them at certain regions because of the interaction between equatorial Kelvin and Rossby waves. The Rossby wave train primarily excited by horizontal divergence of upper-level perturbation flow propagates northeastward and then heads back to the equator. In this way, Rossby wave activity once generated over the subtropical Indian Ocean tends to enhance the equatorial upper-tropospheric anomalies over the tropical Atlantic and West Africa that have already been created by the zonally propagating equatorial Rossby and Kelvin waves. A ray path tracing reveals that a successive downstream development of Rossby wave train mostly results from the large-scale waves with zonal wavenumbers 2–3 in the Northern Hemisphere and 3–5 in the Southern Hemisphere.
The sensitivity tests show that the overall results are quite robust. It is found, however, that the detailed circulation response to the MJO-like forcing is somewhat sensitive to the background flow. This suggests that MJO-related circulation anomalies may have nonnegligible long-term variability and change as background flow varies.
Effects of Ovariectomy and Estrogen Replacement Therapy on Laryngeal Tissue
Authors: Tatlıpınar Arzu , Güneş Pembegül , Özbeyli Dilek , Çimen Burak , Gökçeer Tanju 
Published: September 2011

ObjectiveTo determine the histopathological effect of estrogen deficiency and hormone replacement treatment on laryngeal tissue in ovariectomized rats.Study DesignAnimal study.SettingThe study was conducted at the animal experiment laboratory of Marmara University School of Medicine, Istanbul, Turkey.Subjects and MethodsSix‐month‐old female Wistar albino rats were divided into the following 3 groups (n = 8 per group): sham‐operated control, ovariectomized, and ovariectomized with estrogen replacement. Rats in the ovariectomized with estrogen replacement group received 17 β‐estradiol valerate (200 µg/kg, subcutaneously) once a week. Animals were killed after 8 weeks of intervention.ResultsSignificant changes were observed in the ovariectomized group when edema in lamina propria, inflammation in squamous, respiratory epithelia and lamina propria, pseudostratification, and cilia loss were assessed. Except cilia loss, there were no significant differences in the assessments between the sham‐operated control and ovariectomized with estrogen replacement groups.ConclusionsOn the basis of histopathological evaluations, it was shown that estrogen replacement helped to improve laryngeal changes due to experimentally induced menopause.
Inhibition of Rac GTPase signaling and downstream prosurvival Bcl-2 proteins as combination targeted therapy in MLL-AF9 leukemia
Authors: Mizukawa Benjamin , Wei Junping , Shrestha Mahesh , Wunderlich Mark , Chou Fu-Sheng , Griesinger Andrea , Harris Chad E. , Kumar Ashish R. , Zheng Yi , Williams David A. , Mulloy James C. 
Published: September 2011

AbstractThe Rac family of small Rho GTPases coordinates diverse cellular functions in hematopoietic cells including adhesion, migration, cytoskeleton rearrangements, gene transcription, proliferation, and survival. The integrity of Rac signaling has also been found to critically regulate cellular functions in the initiation and maintenance of hematopoietic malignancies. Using an in vivo gene targeting approach, we demonstrate that Rac2, but not Rac1, is critical to the initiation of acute myeloid leukemia in a retroviral expression model of MLL-AF9 leukemogenesis. However, loss of either Rac1 or Rac2 is sufficient to impair survival and growth of the transformed MLL-AF9 leukemia. Rac2 is known to positively regulate expression of Bcl-2 family proteins toward a prosurvival balance. We demonstrate that disruption of downstream survival signaling through antiapoptotic Bcl-2 proteins is implicated in mediating the effects of Rac2 deficiency in MLL-AF9 leukemia. Indeed, overexpression of Bcl-xL is able to rescue the effects of Rac2 deficiency and MLL-AF9 cells are exquisitely sensitive to direct inhibition of Bcl-2 family proteins by the BH3-mimetic, ABT-737. Furthermore, concurrent exposure to NSC23766, a small-molecule inhibitor of Rac activation, increases the apoptotic effect of ABT-737, indicating the Rac/Bcl-2 survival pathway may be targeted synergistically.
Anti–IL6-receptor-alpha (tocilizumab) does not inhibit human monocyte-derived dendritic cell maturation or alloreactive T-cell responses
Authors: Betts Brian C. , St Angelo Erin T. , Kennedy Michael , Young James W. 
Published: September 2011

AbstractSignificant comorbidites and lethality complicate GVHD and its treatment. Targeting the cytokine milieu may improve GVHD control; and IL6 is an attractive candidate, given its role in dendritic cell activation and T-cell differentiation. Tocilizumab is a humanized mAb to IL6-receptor-α (IL6R-α), which is Food and Drug Administration–approved for treatment of rheumatoid arthritis. Mouse transplant models have demonstrated that IL6 blockade also improves GVHD scores and survival. Definitive immunologic effects of IL6 inhibition have not emerged given inconsistent alterations in regulatory T cells (Tregs) and suppression of T-cell proliferation. Despite on-target suppression of IL6R-α signaling in human monocyte-derived dendritic cells (moDCs) and T cells, our data show no effect on moDC maturation/activation, alloreactive T-cell proliferation, Treg expansion, or allogeneic Th1/Th17 responses in vitro. These findings merit attention in any clinical trials of tocilizumab for GVHD prevention or treatment and provide a rationale for evaluating more specific inhibitors of downstream JAK2/STAT3 signaling as well.
Proteomic detection of a large amount of SCGFα in the stroma of GISTs after imatinib therapy
Authors: Da Riva Luca , Bozzi Fabio , Mondellini Piera , Miccichè Francesca , Fumagalli Elena , Vaghi Elena , Tarantino Eva , Huber Veronica , Gronchi Alessandro , Tamborini Elena , Pierotti Marco A , Pilotti Silvana , Bongarzone Italia 
Published: September 2011

Abstract

Background
Gastrointestinal stromal tumors (GISTs) are the most frequent mesenchymal tumors to develop in the digestive tract. These tumors are highly resistant to conventional chemotherapy and only the introduction of imatinib mesylate has improved the prognosis of patients. However, Response Evaluation Criteria in Solid Tumors are inappropriate for assessing tumor response, and the histological/pathological response to imatinib is variable, heterogeneous, and does not associate with clinical response. The effects of imatinib on responding GISTs are still being explored, and few studies correlate the clinical response with the histological response after pharmacological treatment. Recently, apoptosis and autophagy were suggested as possible alternative mechanisms of pharmacological response.

Methods
Here, we used a proteomic approach, combined with other analyses, to identify some molecular stromal components related to the response/behavior of resected, high-risk GISTs after neoadiuvant imatinib therapy.

Results
Our proteomic results indicate an elevated concentration of Stem Cell Growth Factor (SCGF), a hematopoietic growth factor having a role in the development of erythroid and myeloid progenitors, in imatinib-responsive tumor areas. SCGFα expression was detected by mass spectrometry, immunohistochemistry and/or western blot and attributed to acellular matrix of areas scored negative for KIT (CD117). RT-PCR results indicated that GIST samples did not express SCGF transcripts. The recently reported demonstration by Gundacker et al. [1] of the secretion of SCGF in mature pro-inflammatory dendritic cells would indicate a potential importance of SCGF in tissue inflammatory response. Accordingly, inflammatory infiltrates were detected in imatinib-affected areas and the CD68-positivity of the SCGF-positive and KIT-negative areas suggested previous infiltration of monocytes/macrophages into these regions. Thus, chronic inflammation subsequent to imatinib treatment may determine monocyte/macrophage recruitment in imatinib-damaged areas; these areas also feature prominent tumor-cell loss that is replaced by dense hyalinization and fibrosis.

Conclusions
Our studies highlight a possible role of SCGFα in imatinib-induced changes of GIST structure, consistent with a therapeutic response.
Nanoscale potassium niobate crystal structure and phase transition
Authors: Chen Haiyan , Zhang Yixuan , Lu Yanling 
Published: September 2011

AbstractNanoscale potassium niobate (KNbO3) powders of orthorhombic structure were synthesized using the sol-gel method. The heat-treatment temperature of the gels had a pronounced effect on KNbO3 particle size and morphology. Field emission scanning electron microscopy and transmission electron microscopy were used to determine particle size and morphology. The average KNbO3 grain size was estimated to be less than 100 nm, and transmission electron microscopy images indicated that KNbO3 particles had a brick-like morphology. Synchrotron X-ray diffraction was used to identify the room-temperature structures using Rietveld refinement. The ferroelectric orthorhombic phase was retained even for particles smaller than 50 nm. The orthorhombic to tetragonal and tetragonal to cubic phase transitions of nanocrystalline KNbO3 were investigated using temperature-dependent powder X-ray diffraction. Differential scanning calorimetry was used to examine the temperature dependence of KNbO3 phase transition. The Curie temperature and phase transition were independent of particle size, and Rietveld analyses showed increasing distortions with decreasing particle size.
Mixed monotone-generalized contractions in partially ordered probabilistic metric spaces
Authors: Ćirić Ljubomir , Agarwal Ravi P , Samet Bessem 
Published: September 2011

AbstractIn this article, a new concept of mixed monotone-generalized contraction in partially ordered probabilistic metric spaces is introduced, and some coupled coincidence and coupled fixed point theorems are proved. The theorems Presented are an extension of many existing results in the literature and include several recent developments.Mathematics Subject Classification: Primary 54H25; Secondary 47H10.
How recombinant swollenin from Kluyveromyces lactisaffects cellulosicsubstrates and accelerates their hydrolysis
Authors: Jäger Gernot , Girfoglio Michele , Dollo Florian , Rinaldi Roberto , Bongard Hans , Commandeur Ulrich , Fischer Rainer , Spiess Antje C , Büchs Jochen 
Published: September 2011

Abstract

Background
In order to generate biofuels, insoluble cellulosic substrates are pretreated andsubsequently hydrolyzed with cellulases. One way to pretreat cellulose in a safeand environmentally friendly manner is to apply, under mild conditions,non-hydrolyzing proteins such as swollenin - naturally produced in low yields bythe fungus Trichoderma reesei. To yield sufficient swollenin forindustrial applications, the first aim of this study is to present a new way ofproducing recombinant swollenin. The main objective is to show how swolleninquantitatively affects relevant physical properties of cellulosic substrates andhow it affects subsequent hydrolysis.

Results
After expression in the yeast Kluyveromyces lactis, the resultingswollenin was purified. The adsorption parameters of the recombinant swolleninonto cellulose were quantified for the first time and were comparable to those ofindividual cellulases from T. reesei. Four different insoluble cellulosicsubstrates were then pretreated with swollenin. At first, it could bequalitatively shown by macroscopic evaluation and microscopy that swollenin causeddeagglomeration of bigger cellulose agglomerates as well as dispersion ofcellulose microfibrils (amorphogenesis). Afterwards, the effects of swollenin oncellulose particle size, maximum cellulase adsorption and cellulose crystallinitywere quantified. The pretreatment with swollenin resulted in a significantdecrease in particle size of the cellulosic substrates as well as in theircrystallinity, thereby substantially increasing maximum cellulase adsorption ontothese substrates. Subsequently, the pretreated cellulosic substrates werehydrolyzed with cellulases. Here, pretreatment of cellulosic substrates withswollenin, even in non-saturating concentrations, significantly accelerated thehydrolysis. By correlating particle size and crystallinity of the cellulosicsubstrates with initial hydrolysis rates, it could be shown that theswollenin-induced reduction in particle size and crystallinity resulted in highcellulose hydrolysis rates.

Conclusions
Recombinant swollenin can be easily produced with the robust yeast K.lactis. Moreover, swollenin induces deagglomeration of celluloseagglomerates as well as amorphogenesis (decrystallization). For the first time,this study quantifies and elucidates in detail how swollenin affects differentcellulosic substrates and their hydrolysis.
Low-temperature Ammonothermal Synthesis of LaTaON2
Authors: Watanabe Tomoaki , Tajima Keisuke , Li JinWang , Matsushita Nobuhiro , Yoshimura Masahiro 
Published: September 2011

Abstract
Pure perovskite-type LaTaON2 crystal powders with high crystallinity were synthesized in supercritical ammonia using sodium amide as a flux. The synthesis temperature for this new method is 873 K, approximately 300 K lower than that for previous methods. The obtained powders have a pseudocubic lattice with a lattice constant of a = 0.4049 nm, which is in good agreement with the reported value.
Fabrication and Photocatalytic Properties of TiO2 Nanotube Arrays Modified with Phosphate
Authors: Nakata Kazuya , Liu Baoshun , Ishikawa Yosuke , Sakai Munetoshi , Saito Hidenori , Ochiai Tsuyoshi , Sakai Hideki , Murakami Taketoshi , Abe Masahiko , Takagi Katsuhiko , Fujishima Akira 
Published: September 2011

Abstract
We have prepared TiO2 nanotubes by anodization in HF or HF/H3PO4 mixed electrolyte. The morphologies and photocatalytic properties of the nanotubes were changed by electrolytes. The nanotubes prepared in HF/H3PO4 mixed electrolyte showed higher performance to decompose acetaldehyde by photocatalysis than those prepared in pure HF.
Practical Synthesis of Cyclic Bis(3′–5′)diadenylic Acid (c-di-AMP)
Authors: Suzuki Noritaka , Oyama Kin-ichi , Tsukamoto Masaki 
Published: September 2011

Abstract
Cyclic bis(3′–5′)diadenylic acid (c-di-AMP) (Chart 1), recently identified as a second messenger monitoring DNA integrity during sporulation in the soil bacterium Bacillus subtilis, was synthesized on an 80 µmol scale by a combination of the phosphoramidite and phosphotriester methods using a commercially available adenosine phosphoramidite as starting material. An artificial analog 2′-bis(tert-butyldimethylsilyl)-c-di-AMP was also obtained by our procedure.
Surface Modification of Boron Nitride Nanoparticles by Decylphosphonic Acid Characterized by Solid-state NMR
Authors: Souma Hiroyuki , Hayashi Shigenobu 
Published: September 2011

Abstract
We have attempted to modify the surface of boron nitride (BN) nanoparticles by decylphosphonic acid and have characterized the surface layer of BN nanoparticles by means of high-resolution solid-state 31P NMR. The surface of BN nanoparticles was successfully modified, and the 31P NMR spectra showed two types of bonding states for the organic modifier. They are tentatively assigned to P–B and P–N bonding states from consideration of the residual line broadening due to interaction with quadrupole nuclei.