bluuebunny/crossref_metadata_2025_split huggingface dataset:
Vβ cluster sequences reduce the frequency of primary Vβ2 and Vβ14 rearrangements
Authors: Bassing Craig H. , Whitlow Scott , Mostoslovasky Raul , Yang‐Iott Katherine , Ranganath Sheila , Alt Frederick W. 
Published: September 2008

AbstractT‐cell receptor (TCR) β variable region exons are assembled from numerous gene segments in a highly ordered and regulated manner. To elucidate mechanisms and identify cis‐acting elements that control Vβ rearrangement, we generated an endogenous TCR‐β allele with only the Vβ2, Vβ4, and Vβ14 segments. We found that αβ T lineage cells containing this Vβ2–4–14 allele and a wild‐type TCR‐β allele developed normally, but exhibited a significant increase in Vβ2+ and Vβ14+ cells. To quantify Vβ rearrangements on the Vβ2–4–14 allele, we generated αβ T‐cell hybridomas and analyzed TCR‐β rearrangements. Despite the deletion of almost all Vβ segments and 234 kb of Vβ cluster sequences, the Vβ2–4–14 allele exhibited only a slight decrease in Vβ rearrangement as compared with the wild‐type TCR‐β allele. Thus, cis‐acting control elements essential for directing Vβ rearrangement across large chromosomal distances are not located within the Vβ cluster. We also found a significant increase in the frequency of Vβ rearrangements involving Vβ2 and Vβ14, but not Vβ4, on the Vβ2–4–14 allele. Collectively, our data suggest that Vβ cluster sequences reduce the frequency of Vβ2 and Vβ14 rearrangements by competing with the productive coupling of accessible Vβ2 and Vβ14 segments with DJβ1 complexes.
Exogenous IFN‐γ ex vivo shapes the alloreactive T‐cell repertoire by inhibition of Th17 responses and generation of functional Foxp3+ regulatory T cells
Authors: Feng Gang , Gao Wenda , Strom Terry B. , Oukka Mohamed , Francis Ross S. , Wood Kathryn J. , Bushell Andrew 
Published: September 2008

AbstractInterferon (IFN)‐γ was originally characterized as a pro‐inflammatory cytokine with T helper type 1‐inducing activity, but subsequent work has demonstrated that mice deficient in IFN‐γ or IFN‐γ receptor show exacerbated inflammatory responses and accelerated allograft rejection, suggesting that IFN‐γ also has important immunoregulatory functions. Here, we demonstrate that ex vivo IFN‐γ conditioning of CD4 T cells driven by allogeneic immature dendritic cells (DC) results in the emergence of a Foxp3+ regulatory T‐cell (Treg)‐ dominant population that can prevent allograft rejection. The development of this population involves conversion of non‐Treg precursors, preferential induction of activation‐induced cell death within the non‐Treg population and suppression of Th2 and Th17 responses. The suppressive activity of IFN‐γ is dependent on the transcription factor signal transducer and activator of transcription 1 and is mediated by induced nitric oxide. These data indicate not only how IFN‐γ could be used to shape beneficial immune responses ex vivo for possible cell therapy but also provide some mechanistic insights that may be relevant to exacerbated inflammatory responses noted in several autoimmune and transplant models with IFN‐γ deficiency.
The thiol redox state of lymphoid organs is modified by immunization: Role of different immune cell populations
Authors: Castellani Patrizia , Angelini Giovanna , Delfino Laura , Matucci Andrea , Rubartelli Anna 
Published: September 2008

AbstractResting T lymphocytes can internalize reduced cysteine (Cys) but not cystine, the oxidized form of the amino acid that predominates extracellularly. In vitro studies have shown that DC provide Cys to T cells during antigen presentation, allowing their activation. Here, we show that increased thiol production is a hallmark of immune response in vivo. Indeed, the thiol content of LN increases dramatically after antigen injection. Non‐protein thiols co‐distribute with DC and are highly abundant in germinal centers. In agreement, activated but not resting B lymphocytes and macrophages release free thiols. Increased thiol release following activation requires thioredoxin and is paralleled by increased thioredoxin expression. The T zones of LN are consistently less stained, and both resting and activated T cells are unable to release thiols. Interestingly, the cystine/glutamate transporter x is absent in resting T lymphocytes but is rapidly induced by TCR triggering in vitro, indicating that the release of T cells from the need of exogenous Cys occurs early after activation. These results indicate that a reducing microenvironment is essential to start the immune response but dispensable for its evolution, and support the emerging concept that extracellular redox is implicated in the control of crucial cellular functions.
Supercritical extraction of borage seed oil coupled to conventional solvent extraction of antioxidants
Authors: Soto Carmen , Conde Enma , Moure Andrés , Zúñiga María Elvira , Domínguez Herminia 
Published: September 2008

AbstractThis paper describes the extraction of borage seed oil by supercritical carbon dioxide (SC‐CO2) and the further extraction of antioxidants from the SC‐CO2‐defatted borage meal with organic solvents (water, methanol, ethanol and ethyl acetate). The optimal conditions for oil extraction were obtained at 303 and 323 K at 200 bar, 2.5 h and a continuous flow of CO2 of 1.5 L/h introduced through the bottom when the operating pressure and temperature were reached, attaining a yield of 60%. Borage oil is rich in unsaturated fatty acids; oleic acid, linoleic acid and linolenic acid accounted for 74% of the total fatty acid content under the above conditions. The highest extraction yield was achieved using water or methanol as extracting solvent from the SC‐CO2‐defatted borage meal at 303 K and pressures of 200 and 150 bar for water and methanol, respectively. The most potent extracts, according to all methods tested, were obtained with water and methanol.
Sociocultural influences on body dissatisfaction and dieting in Hong Kong girls
Authors: Lam T. H. , Lee Stephanie W. , Fung Samantha , Ho S. Y. , Lee Peter W. H. , Stewart Sunita M. 
Published: September 2008

AbstractWe investigated the relationship of sociocultural influences (SI) promoting thinness (parental, peer and media pressures for thinness, and individual value for modernity), age and body mass Index (BMI) to body dissatisfaction (BD) and dieting in 294 Hong Kong community adolescent girls. We proposed that BD mediated SI's relationship with dieting. In bivariate analyses, all variables were significantly (p ≤ .05) related to BD (ß's from 0.14 to 0.59), and, except for modernity, to dieting (ß's from 0.17 to 0.51). In multivariate analyses, peer (ß = 0.32, p < .001) and media pressures for thinness (ß = 0.18, p < .01) bypassed BD and were directly associated with dieting. A culture of thinness appears to be associated with weight loss efforts among girls in modernising cultures independent of BD. Our findings call for public policy to restrict promotion of the impossibly thin ideal, and public education regarding the paradoxical effects of dieting. Copyright © 2008 John Wiley & Sons, Ltd and Eating Disorders Association.
A DFT‐based phasor estimation method for power electronics converter control and protection under strong grid voltage perturbations
Authors: Martins António Pina 
Published: September 2008

AbstractPower conditioning systems like active filters, universal power flow controllers, static compensators, and dynamic voltage restorers, among other ones, need accurate synchronization circuits capable of dealing with very different grid voltage perturbations. The DFT algorithm is one of best performers in phasor estimation, but is not perfect. The paper accurately describes the DFT errors under frequency variation, decaying DC components and harmonics, and analyzes the instantaneous phasor estimation, with absolute and recursive algorithms. Strong grid voltage perturbations, occurring in weak grids, especially in the grid connection of renewable energies, demand for a DFT‐based robust estimation method. The proposed method, as demonstrated by extensive simulations, is capable of handling general grid voltage perturbations, imposing a compromise between dynamic response and accuracy. Also, its advantage over two other frequently used methods is demonstrated by comparative results. Copyright © 2008 John Wiley & Sons, Ltd.
Performance limits of multiple‐input multiple‐output keyhole channels with antenna selection
Authors: Müller Andreas , Speidel Joachim 
Published: September 2008

AbstractWe present a comprehensive analysis of the ergodic capacity and information outage probability of multiple‐input multiple‐output (MIMO) keyhole channels with antenna selection. In this regard, we consider several different scenarios with perfect channel state information (CSI) at the receiver and no, partial or full CSI at the transmitter. For all cases, we derive exact analytical closed‐form expressions for the corresponding outage probability and ergodic capacity, where the latter one is always given as a finite sum of weighted Meijer G‐functions, which might be easily evaluated numerically using standard mathematical software packages. Furthermore, we derive somewhat simpler upper and lower capacity bounds, which are proven to be asymptotically tight in the high SNR regime. Numerical results are shown to be in perfect agreement with results obtained from Monte Carlo simulations, thus verifying the accuracy of our theoretical analysis. Copyright © 2008 John Wiley & Sons, Ltd.
On PMEPR of algebraic codes
Authors: Alrod Idan , Litsyn Simon , Yudin Alexander 
Published: September 2008

AbstractNew bounds on the ratio between the discrete and continuous maxima of multicarrier (MC) signals are derived. In contrast to the earlier known results, these bounds depend on the value of the discrete maximum. Use of the bounds yields improved estimates for the peak‐to‐mean envelope power ratio (PMEPR) of trace codes. Copyright © 2008 John Wiley & Sons, Ltd.
Exponential time integration using Krylov subspaces
Authors: Schulze J. C. , Schmid P. J. , Sesterhenn J. L. 
Published: September 2008

AbstractThe application of exponential integrators based on Krylov techniques to large‐scale simulations of complex fluid flows with multiple time‐scales demonstrates the efficiency of these schemes in reducing the associated time‐step restrictions due to numerical stiffness. Savings of approximately 50% can be achieved for simulations of the three‐dimensional compressible Navier–Stokes equations while still maintaining a truncation error typical of explicit time‐stepping schemes. Exponential time integration techniques of this type are particularly advantageous for fluid flows with a wide range of temporal scales such as low‐Mach number, reactive or acoustically dominated flows. Copyright © 2008 John Wiley & Sons, Ltd.
Concomitant presence of mutations in mitochondrial genome and p53 in cancer development—A study in north Indian sporadic breast and esophageal cancer patients
Authors: Gochhait Sailesh , Bhatt Audesh , Sharma Swarkar , Singh Yoginder Pal , Gupta Pawan , Bamezai Rameshwar N.K. 
Published: September 2008

AbstractMitochondrial DNA alterations in recent years have been suggested as modifier events, providing a possible proliferative advantage to the tumor cells. In order to provide further insight into the process of tumorigenesis, a study of whole mitochondria genome was conducted in 134 tissue samples obtained from 2 unrelated cancers (tumor and adjacent normal tissues from 36 breast cancer and 31 esophageal squamous cell carcinoma (ESCC) patients) with known p53 somatic mutation background. Fifteen of 36 (41.66%) breast and 12 of 31 (38.71%) ESCC tumors were found to contain at least 1 mtDNA somatic mutation, which correlated significantly with the concomitant presence of somatic mutation in DNA binding domain of the p53 gene (Breast cancer, p = 0.006; ESCC, p = 0.002). Interestingly, mutations in the non D‐loop region of the mtDNA contributed significantly (Breast cancer, p = 0.004; ESCC, p = 0.032) in comparison to the hotspot‐D‐Loop‐region. The concomitant presence of mutations in p53 and mtDNA were also predominant in breast cancer tumors with poor prognosis, that is, with the advanced stage, grade and the ER/PR negativity. Also, the observation made was apparently well explained in 10398A bearing N haplogroup genetic background with increased presence of novel and pathogenic germline mutation in mtDNA. Our study suggests that the concomitant presence of somatic alteration in mtDNA and the DNA binding domain of the p53 gene facilitates cell survival and tumorigenesis, requiring specialized therapeutic intervention because of a possible resistance to conventional chemotherapy. © 2008 Wiley‐Liss, Inc.
Chemotherapy safety and severe adverse events in cancer patients: Strategies to efficiently avoid chemotherapy errors in in‐ and outpatient treatment
Authors: Markert Anna , Thierry Véronique , Kleber Martina , Behrens Michael , Engelhardt Monika 
Published: September 2008

AbstractTo enhance the quality and safety in cancer treatment, and in acknowledgement that medical errors occur, we have established 2 error management systems: one monitors chemotherapy errors, the other records all severe adverse events occurring in chemotherapy‐treated cancer patients (SAECTx) in in‐ and outpatient treatment. These error systems have been implemented by our departmental “Clinical Service Center,” a multidisciplinary team which controls all chemotherapy protocols and orders prior to the medication reaching the patient. We performed a prospective cohort study in consecutive cancer patients who received chemotherapies in our department between January 2005 and December 2006. Over this 2‐year period, 2,337 patients were treated, with an equal distribution as in‐ and outpatients: 22,216 consecutive chemotherapy orders were analyzed, of which 83.5% were completely flawless, whereas we detected and corrected medical and administrative errors in 17.1%: in 3.8%, these errors involved the chemotherapy itself, in 4.5% the patient data and in 8.7% missing written informed consent forms. Chemotherapy errors were less frequent in outpatients than inpatients (3.3 vs. 4.5%, respectively). In outpatients, the rate of chemotherapy errors decreased from 4% in 2005 to 2.8% in 2006, but remained stable for inpatients (4.4% 2005 vs. 4.7% 2006). Among a total of 3,792 detected errors, only 3 reached the patient, resulting in an error rate in patients of 0.079%. Therefore, since we detected a substantial number of chemotherapy‐related errors and intercepted 99.9%, we recommend our efficient surveillance system as an important safety check, thereby ensuring that chemotherapies are delivered error‐free to cancer patients. © 2008 Wiley‐Liss, Inc.
An HIV protease inhibitor, ritonavir targets the nuclear factor‐kappaB and inhibits the tumor growth and infiltration of EBV‐positive lymphoblastoid B cells
Authors: Dewan Md. Zahidunnabi , Tomita Mariko , Katano Harutaka , Yamamoto Norio , Ahmed Sunjida , Yamamoto Michiko , Sata Tetsutaro , Mori Naoki , Yamamoto Naoki 
Published: September 2008

AbstractEpstein‐Barr Virus (EBV)‐associated immunoblastic lymphoma occurs in immunocompromised patients such as those with AIDS or transplant recipients after primary EBV infection or reactivation of a preexisting latent EBV infection. In the present study, we evaluated the effect of ritonavir, an HIV protease inhibitor, on EBV‐positive lymphoblastoid B cells in vitro and in mice model. We found that it induced cell‐cycle arrest at G1‐phase and apoptosis through down‐regulation of cell‐cycle gene cyclin D2 and antiapoptotic gene survivin. Furthermore, ritonavir suppressed transcriptional activation of NF‐κB in these cells. Ritonavir efficiently prevented growth and infiltration of lymphoma cells in various organs of NOD/SCID/γcnull mice at the same dose used for treatment of patients with AIDS. Our results indicate that ritonavir targets NF‐κB activated in tumor cells and shows anti‐tumor effects. These data also suggest that this compound may have promise for treatment or prevention of EBV‐associated lymphoproliferative diseases that occur in immunocompromised patients. © 2008 Wiley‐Liss, Inc.
Targeting Src signaling in metastatic bone disease
Authors: Araujo John , Logothetis Christopher 
Published: September 2008

AbstractSrc is a tyrosine kinase involved in the regulation of a range of cellular processes including proliferation, adhesion, motility and survival. In addition, it is a key regulator of bone metabolism. Src has been implicated in the pathogenesis of a number of cancers, and has been found to be overexpressed in breast, prostate, colorectal, pancreatic and nonsmall‐cell lung tumors. There is also evidence that aberrant Src signaling may contribute to the increased osteoclastic activity associated with bone metastases. Bone metastases frequently occur in cancer patients with advanced disease. The metastasized cells disrupt normal bone remodeling pathways resulting in the release of growth factors that further promote tumor growth. Thus, a cycle of metastatic bone destruction is initiated, leading to compromised skeletal integrity and substantially reduced quality of life. Because of the role of Src in both cancer development and in bone metabolism, it may provide a therapeutic target for patients with bone metastases. © 2008 Wiley‐Liss, Inc.
Biodegradable honeycomb collagen scaffold for dermal tissue engineering
Authors: George Joseph , Onodera Jun , Miyata Teruo 
Published: September 2008

AbstractTissue engineering requires a mechanically stable, biocompatible, and biodegradable scaffold that permits cell adherence and proliferation, allows preservation of cell‐specific properties, and suitable for surgical implantations. In this study, honeycomb collagen sheet was used for three‐dimensional (3D) cultures of human skin fibroblasts and characterized as an effective and suitable scaffold for dermal tissue engineering. About 1‐mm‐thick honeycomb collagen sheets, prepared from bovine dermal atelocollagen, cross‐linked by UV‐irradiation, and sterilized by heat, were placed on the proliferating fibroblasts on day 3 of the culture. The cells attached quickly to the collagen scaffold, proliferated inside the honeycomb pores, and formed a structure similar to dermis within 60 days. On day 60, total cellular DNA content of the 3D cultures was 12‐fold higher when compared with the 2D control cultures without the scaffold. Measurement of procollagen type I in the media demonstrated a 20‐fold increase. Scanning electron microscopy of the 3D cultures showed a well‐formed structure similar to dermis and biodegradation of the honeycomb collagen scaffold. Our study proved that honeycomb collagen sheet is a mechanically stable, biocompatible and biodegradable scaffold for dermal tissue engineering, and also potentially useful for other cell‐based therapies and tissue engineering applications. © 2008 Wiley Periodicals, Inc. J Biomed Mater Res, 2008
Role of the feline immunodeficiency virus L‐domain in the presence or absence of Gag processing: Involvement of ubiquitin and Nedd4‐2s ligase in viral egress
Authors: Calistri Arianna , Del Vecchio Claudia , Salata Cristiano , Celestino Michele , Celegato Marta , Göttlinger Heinrich , Palù Giorgio , Parolin Cristina 
Published: September 2008

AbstractRNA‐enveloped viruses bud from infected cells by exploiting the multivesicular body (MVB) pathway. In this context, ubiquitination of structural viral proteins and their direct interaction with cellular factors involved in the MVB biogenesis through short proline rich regions, named late domains (L‐domains), are crucial mechanisms. Here we report that, in contrast with the human immunodeficiency virus (HIV), the feline immunodeficiency virus (FIV), a non‐primate lentivirus, is strictly dependent for its budding on a “PSAP”‐type L‐domain, mapping in the carboxy‐terminal region of Gag, irrespective of a functional viral protease. Moreover, we provide evidence that FIV egress is related to Gag ubiquitination, that is, linked to the presence of an active L‐domain. Finally, although FIV Gag does not contain a PPxY motif, we show that the Nedd4‐2s ubiquitin ligase enhances FIV Gag ubiquitination and it is capable to rescue viral mutants lacking a functional L‐domain. In conclusion, our data bring to light peculiar aspects of FIV egress, but we also demonstrate that a non‐primate lentivirus shares with HIV‐1 a novel mechanism of connection to the cellular budding machinery. J. Cell. Physiol. 218: 175–182, 2009. © 2008 Wiley‐Liss, Inc.
Soluble and insoluble nickel compounds exert a differential inhibitory effect on cell growth through IKKα‐dependent cyclin D1 down‐regulation
Authors: Ouyang Weiming , Zhang Dongyun , Li Jingxia , Verma Udit N. , Costa Max , Huang Chuanshu 
Published: September 2008

AbstractIt is well‐known that insoluble nickel compounds possess much more potent carcinogenic activities as compared with soluble nickel compounds. Although it is assumed that the different entry and clearance rate are responsible for the difference, the mechanisms underlying the different carcinogenic activities are still not well understood yet. In the present study, we found that exposure to soluble, but not insoluble nickel compounds, caused a significant inhibition of cell growth and G1/G0 cell cycle arrest, which was concomitant with a marked down‐regulation of cylin D1, an essential nuclear protein for controlling G1/S transition, while both soluble and insoluble nickel compounds showed similar effects on NFκB activation, HIF‐1α protein accumulation and TNF‐α transcription and CAP43 protein expression at same doses range. The down‐regulation of cyclin D1 is due to protein degradation rather than inhibition of transcription, because the nickel compounds treatment did not change cyclin D1 mRNA level, while MG132, the proteasome inhibitor, can rescue the degradation of cyclin D1 caused by soluble nickel compound. Moreover, the soluble nickel‐induced cyclin D1 degradation is dependent on its Thr286 residue and requires IKKα, but not HIF‐1α, which are both reported to be involved in cyclin D1 down‐regulation. Taken together, we demonstrate that soluble, but not insoluble nickel compound, is able to cause cyclin D1 degradation and a cell growth arrest in an IKKα‐dependent manner. Given the role of cyclin D1 and cell proliferation in carcinogenesis, we anticipate that the different effects of soluble and insoluble nickel compounds on cyclin D1 degradation and cell growth arrest may at least partially account for their different carcinogenic activities. J. Cell. Physiol. 218: 205–214, 2009. © 2008 Wiley‐Liss, Inc.
Decolorization of Direct Blue GLL with enhanced lignin peroxidase enzyme production in Comamonas sp UVS
Authors: Jadhav Umesh U. , Dawkar Vishal V. , Telke Amar A. , Govindwar Sanjay P. 
Published: September 2008

AbstractBACKGROUND: The present work aims to study the production of lignin peroxidase (LiP) enzyme by Comamonas sp UVS using various media, and lignocellulosic waste materials, and its effect on decolorization of Direct Blue GLL (DBGLL).RESULTS: Yeast extract medium was found to be more effective for the production of LiP and also for the decolorization of DBGLL. The bagasse powder along with yeast extract induced LiP activity. Comamonas sp UVS decolorized DBGLL dye (50 mg L−1) within 13 h at static condition in YE broth. It could degrade up to 300 mg L−1 of dye within 55 h. The maximum rate (Vmax) of decolorization was 12.41 ± 0.55 mg dye g cell−1 h−1 with the Michaelis constant (Km) value as 6.20 ± 0.27 mg L−1. The biodegradation was monitored by UV‐Vis, GC‐MS and HPLC.CONCLUSION: The use of agricultural by‐products for the activity enhancement of the ligninolytic enzymes is a cost effective process. It also resolves the problem of the disposal of agro‐residues. This system can be applied for the degradation of different recalcitrant compounds. Copyright © 2008 Society of Chemical Industry