bluuebunny/crossref_metadata_2025_split huggingface dataset:
Efficacy of tyrosine kinase inhibitors (TKIs) as third-line therapy in patients with chronic myeloid leukemia in chronic phase who have failed 2 prior lines of TKI therapy
Authors: Ibrahim Amr R. , Paliompeis Christos , Bua Marco , Milojkovic Dragana , Szydlo Richard , Khorashad Jamshid S. , Foroni Letizia , Reid Alistair , de Lavallade Hugues , Rezvani Katayoun , Dazzi Francesco , Apperley Jane F. , Goldman John M. , Marin David 
Published: September 2010

Abstract
We analyzed a cohort of 26 patients with chronic myeloid leukemia who had failed imatinib and a second tyrosine kinase inhibitor but were still in first chronic phase and identified prognostic factors for response and outcomes. The achievement of a prior cytogenetic response on imatinib or on second-line therapy were the only independent predictors for the achievement of complete cytogenetic responses on third-line therapy. Younger age and the achievement of a cytogenetic response on second line were the only independent predictors for overall survival (OS). At 3 months, the 9 patients who had achieved a cytogenetic response had better 30-month probabilities of complete cytogenetic responses and OS than the patients who had failed to do so. Factors measurable before starting treatment with third line therapy and cytogenetic responses at 3 months can accurately predict subsequent outcome and thus guide clinical decisions.
Characterization of tetracycline modifying enzymes using a sensitive in vivo reporter system
Authors: Yu Zhou , Reichheld Sean E , Cuthbertson Leslie , Nodwell Justin R , Davidson Alan R 
Published: September 2010

Abstract

Background
Increasing our understanding of antibiotic resistance mechanisms is critical. To enable progress in this area, methods to rapidly identify and characterize antibiotic resistance conferring enzymes are required.

Results
We have constructed a sensitive reporter system in Escherichia coli that can be used to detect and characterize the activity of enzymes that act upon the antibiotic, tetracycline and its derivatives. In this system, expression of the lux operon is regulated by the tetracycline repressor, TetR, which is expressed from the same plasmid under the control of an arabinose-inducible promoter. Addition of very low concentrations of tetracycline derivatives, well below growth inhibitory concentrations, resulted in luminescence production as a result of expression of the lux genes carried by the reporter plasmid. Introduction of another plasmid into this system expressing TetX, a tetracycline-inactivating enzyme, caused a marked loss in luminescence due to enzyme-mediated reduction in the intracellular Tc concentration. Data generated for the TetX enzyme using the reporter system could be effectively fit with the known K
m and k
cat values, demonstrating the usefulness of this system for quantitative analyses.

Conclusion
Since members of the TetR family of repressors regulate enzymes and pumps acting upon almost every known antibiotic and a wide range of other small molecules, reporter systems with the same design as presented here, but employing heterologous TetR-related proteins, could be developed to measure enzymatic activities against a wide range of antibiotics and other compounds. Thus, the assay described here has far-reaching applicability and could be adapted for high-throughput applications.
Alterations in Vitamin D signalling and metabolic pathways in breast cancer progression: a study of VDR, CYP27B1 and CYP24A1 expression in benign and malignant breast lesions Vitamin D pathways unbalanced in breast lesions
Authors: Lopes Nair , Sousa Bárbara , Martins Diana , Gomes Madalena , Vieira Daniella , Veronese Luiz A , Milanezi Fernanda , Paredes Joana , Costa José L , Schmitt Fernando 
Published: September 2010

Abstract

Background
Breast cancer is a heterogeneous disease associated with different patient prognosis and responses to therapy. Vitamin D has been emerging as a potential treatment for cancer, as it has been demonstrated that it modulates proliferation, apoptosis, invasion and metastasis, among others. It acts mostly through the Vitamin D receptor (VDR) and the synthesis and degradation of this hormone are regulated by the enzymes CYP27B1 and CYP24A1, respectively. We aimed to study the expression of these three proteins by immunohistochemistry in a series of breast lesions.

Methods
We have used a cohort comprising normal breast, benign mammary lesions, carcinomas in situ and invasive carcinomas and assessed the expression of the VDR, CYP27B1 and CYP24A1 by immunohistochemistry.

Results
The results that we have obtained show that all proteins are expressed in the various breast tissues, although at different amounts. The VDR was frequently expressed in benign lesions (93.5%) and its levels of expression were diminished in invasive tumours (56.2%). Additionally, the VDR was strongly associated with the oestrogen receptor positivity in breast carcinomas. CYP27B1 expression is slightly lower in invasive carcinomas (44.6%) than in benign lesions (55.8%). In contrast, CYP24A1 expression was augmented in carcinomas (56.0% in in situ and 53.7% in invasive carcinomas) when compared with that in benign lesions (19.0%).

Conclusions
From this study, we conclude that there is a deregulation of the Vitamin D signalling and metabolic pathways in breast cancer, favouring tumour progression. Thus, during mammary malignant transformation, tumour cells lose their ability to synthesize the active form of Vitamin D and respond to VDR-mediated Vitamin D effects, while increasing their ability to degrade this hormone.
'ZP domain' of human zona pellucida glycoprotein-1 binds to human spermatozoa and induces acrosomal exocytosis
Authors: Ganguly Anasua , Bansal Pankaj , Gupta Tripti , Gupta Satish K 
Published: September 2010

AbstractBackgroundThe human egg coat, zona pellucida (ZP), is composed of four glycoproteins designated as zona pellucida glycoprotein-1 (ZP1), -2 (ZP2), -3 (ZP3) and -4 (ZP4) respectively. The zona proteins possess the archetypal 'ZP domain', a signature domain comprised of approximately 260 amino acid (aa) residues. In the present manuscript, attempts have been made to delineate the functional significance of the 'ZP domain' module of human ZP1, corresponding to 273-551 aa fragment of human ZP1.MethodsBaculovirus-expressed, nickel-nitrilotriacetic acid affinity chromatography purified 'ZP domain' of human ZP1 was employed to assess its capability to bind and subsequently induce acrosomal exocytosis in capacitated human spermatozoa using tetramethyl rhodamine isothiocyanate conjugated Pisum sativum Agglutinin in absence or presence of various pharmacological inhibitors. Binding characteristics of ZP1 'ZP domain' were assessed employing fluorescein isothiocyanate (FITC) labelled recombinant protein.ResultsSDS-PAGE and immunoblot characterization of the purified recombinant protein (both from cell lysate as well as culture supernatant) revealed a doublet ranging from ~35-40 kDa. FITC- labelled 'ZP domain' of ZP1 binds primarily to the acrosomal cap of the capacitated human spermatozoa. A dose dependent increase in acrosomal exocytosis was observed when capacitated sperm were incubated with recombinant 'ZP domain' of human ZP1. The acrosome reaction mediated by recombinant protein was independent of Gi protein-coupled receptor pathway, required extra cellular calcium and involved both T- and L-type voltage operated calcium channels.ConclusionsResults described in the present study suggest that the 'ZP domain' module of human ZP1 has functional activity and may have a role during fertilization in humans.
Role of surface charge and oxidative stress in cytotoxicity of organic monolayer-coated silicon nanoparticles towards macrophage NR8383 cells
Authors: Bhattacharjee Sourav , de Haan Laura HJ , Evers Nynke M , Jiang Xue , Marcelis Antonius TM , Zuilhof Han , Rietjens Ivonne MCM , Alink Gerrit M 
Published: September 2010

Abstract

Background
Surface charge and oxidative stress are often hypothesized to be important factors in cytotoxicity of nanoparticles. However, the role of these factors is not well understood. Hence, the aim of this study was to systematically investigate the role of surface charge, oxidative stress and possible involvement of mitochondria in the production of intracellular reactive oxygen species (ROS) upon exposure of rat macrophage NR8383 cells to silicon nanoparticles. For this aim highly monodisperse (size 1.6 ± 0.2 nm) and well-characterized Si core nanoparticles (Si NP) were used with a surface charge that depends on the specific covalently bound organic monolayers: positively charged Si NP-NH2, neutral Si NP-N3 and negatively charged Si NP-COOH.

Results
Positively charged Si NP-NH2 proved to be more cytotoxic in terms of reducing mitochondrial metabolic activity and effects on phagocytosis than neutral Si NP-N3, while negatively charged Si NP-COOH showed very little or no cytotoxicity. Si NP-NH2 produced the highest level of intracellular ROS, followed by Si NP-N3 and Si NP-COOH; the latter did not induce any intracellular ROS production. A similar trend in ROS production was observed in incubations with an isolated mitochondrial fraction from rat liver tissue in the presence of Si NP. Finally, vitamin E and vitamin C induced protection against the cytotoxicity of the Si NP-NH2 and Si NP-N3, corroborating the role of oxidative stress in the mechanism underlying the cytotoxicity of these Si NP.

Conclusion
Surface charge of Si-core nanoparticles plays an important role in determining their cytotoxicity. Production of intracellular ROS, with probable involvement of mitochondria, is an important mechanism for this cytotoxicity.
Mechanisms of oxidative stress and alterations in gene expression by Libby six-mix in human mesothelial cells
Authors: Hillegass Jedd M , Shukla Arti , MacPherson Maximilian B , Lathrop Sherrill A , Alexeeva Vlada , Perkins Timothy N , van der Vliet Albert , Vacek Pamela M , Gunter Mickey E , Mossman Brooke T 
Published: September 2010

AbstractBackgroundExposures to an amphibole fiber in Libby, Montana cause increases in malignant mesothelioma (MM), a tumor of the pleural and peritoneal cavities with a poor prognosis. Affymetrix microarray/GeneSifter analysis was used to determine alterations in gene expression of a human mesothelial cell line (LP9/TERT-1) by a non-toxic concentration (15×106μm2/cm2) of unprocessed Libby six-mix and negative (glass beads) and positive (crocidolite asbestos) controls. Because manganese superoxide dismutase (MnSOD; SOD2) was the only gene upregulated significantly (p < 0.05) at both 8 and 24 h, we measured SOD protein and activity, oxidative stress and glutathione (GSH) levels to better understand oxidative events after exposure to non-toxic (15×106μm2/cm2) and toxic concentrations (75×106μm2/cm2) of Libby six-mix.ResultsExposure to 15×106μm2/cm2Libby six-mix elicited significant (p < 0.05) upregulation of one gene (SOD2; 4-fold) at 8 h and 111 gene changes at 24 h, including a 5-fold increase inSOD2. Increased levels of SOD2 mRNA at 24 h were also confirmed in HKNM-2 normal human pleural mesothelial cells by qRT-PCR. SOD2 protein levels were increased at toxic concentrations (75×106μm2/cm2) of Libby six-mix at 24 h. In addition, levels of copper-zinc superoxide dismutase (Cu/ZnSOD; SOD1) protein were increased at 24 h in all mineral groups. A dose-related increase in SOD2 activity was observed, although total SOD activity remained unchanged. Dichlorodihydrofluorescein diacetate (DCFDA) fluorescence staining and flow cytometry revealed a dose- and time-dependent increase in reactive oxygen species (ROS) production by LP9/TERT-1 cells exposed to Libby six-mix. Both Libby six-mix and crocidolite asbestos at 75×106μm2/cm2caused transient decreases (p < 0.05) in GSH for up to 24 h and increases in gene expression of heme oxygenase 1 (HO-1) in LP9/TERT-1 and HKNM-2 cells.ConclusionsLibby six-mix causes multiple gene expression changes in LP9/TERT-1 human mesothelial cells, as well as increases in SOD2, increased production of oxidants, and transient decreases in intracellular GSH. These events are not observed at equal surface area concentrations of nontoxic glass beads. Results support a mechanistic basis for the importance of SOD2 in proliferation and apoptosis of mesothelial cells and its potential use as a biomarker of early responses to mesotheliomagenic minerals.
Evaluation of multicomponent recombinant vaccines against Actinobacillus pleuropneumoniae in mice
Authors: Shao Meili , Wang Yong , Wang Chunlai , Guo Yang , Peng Yonggang , Liu Jiandong , Li Guangxing , Liu Huifang , Liu Siguo 
Published: September 2010

AbstractBackgroundPorcine contagious pleuropneumonia (PCP) is a highly contagious disease that is caused byActinobacillus pleuropneumoniae(APP) and characterized by severe fibrinous necrotizing hemorrhagic pleuropneumonia, which is a severe threat to the swine industry. In addition to APP RTX-toxins I (ApxI), APP RTX-toxin II (ApxII), APP RTX-toxin III (ApxIII) and Outer membrane protein (OMP), there may be other useful antigens that can contribute to protection. In the development of an efficacious vaccine against APP, the immunogenicities of multicomponent recombinant subunit vaccines were evaluated.MethodsSix major virulent factor genes of APP, i.e.,apxI,apxII,apxIII, APP RTX-toxins IV (apxIV),ompand type 4 fimbrial structural (apfa) were expressed. BALB/c mice were immunized with recombinant ApxI ( rApxI), recombinant ApxII (rApxII), recombinant ApxIII (rApxIII) and recombinant OMP (rOMP) (Group I); rApxI, rApxII, rApxIII, recombinant ApxIV (rApxIV), recombinant Apfa (rApfa) and rOMP (Group II); APP serotype 1 (APP1) inactivated vaccine (Group III); or phosphate-buffered saline (PBS) (Control group), respectively. After the first immunization, mice were subjected to two booster immunizations at 2-week intervals, followed by challenge with APP1 Shope 4074 and APP2 S1536.ResultsThe efficacy of the multicomponent recombinant subunit vaccines was evaluated on the basis of antibody titers, survival rates, lung lesions and indirect immunofluorescence (IIF) detection of APP. The antibody level of Group I was significantly higher than those of the other three groups (P< 0.05). The survival rate of Group I was higher than that of Groups II and III (P< 0.05) and the control (P< 0.01). Compared with the other three groups, the lungs of Group I did not exhibit obvious hemorrhage or necrosis, and only showed weak and scattered fluorescent dots by IIF detection.ConclusionThe result indicates that the multicomponent recombinant subunit vaccine composed of rApxI, rApxII, rApxIII and rOMP can provide effective cross-protection against homologous and heterologous APP challenge.
Leucine-rich alpha-2-glycoprotein-1 is upregulated in sera and tumors of ovarian cancer patients
Authors: Andersen John D , Boylan Kristin LM , Jemmerson Ronald , Geller Melissa A , Misemer Benjamin , Harrington Katherine M , Weivoda Starchild , Witthuhn Bruce A , Argenta Peter , Vogel Rachel Isaksson , Skubitz Amy PN 
Published: September 2010

AbstractBackgroundNew biomarkers that replace or are used in conjunction with the current ovarian cancer diagnostic antigen, CA125, are needed for detection of ovarian cancer in the presurgical setting, as well as for detection of disease recurrence. We previously demonstrated the upregulation of leucine-rich alpha-2-glycoprotein-1 (LRG1) in the sera of ovarian cancer patients compared to healthy women using quantitative mass spectrometry.MethodsLRG1 was quantified by ELISA in serum from two relatively large cohorts of women with ovarian cancer and benign gynecological disease. The expression of LRG1 in ovarian cancer tissues and cell lines was examined by gene microarray, reverse-transcriptase polymerase chain reaction (RT-PCR), Western blot, immunocytochemistry and mass spectrometry.ResultsMean serum LRG1 was higher in 58 ovarian cancer patients than in 56 healthy women (89.33 ± 77.90 vs. 42.99 ± 9.88 ug/ml; p = 0.0008) and was highest among stage III/IV patients. In a separate set of 193 pre-surgical samples, LRG1 was higher in patients with serous or clear cell ovarian cancer (145.82 ± 65.99 ug/ml) compared to patients with benign gynecological diseases (82.53 ± 76.67 ug/ml, p < 0.0001). CA125 and LRG1 levels were moderately correlated (r = 0.47, p < 0.0001).LRG1mRNA levels were higher in ovarian cancer tissues and cell lines compared to their normal counterparts when analyzed by gene microarray and RT-PCR. LRG1 protein was detected in ovarian cancer tissue samples and cell lines by immunocytochemistry and Western blotting. Multiple iosforms of LRG1 were observed by Western blot and were shown to represent different glycosylation states by digestion with glycosidase. LRG1 protein was also detected in the conditioned media of ovarian cancer cell culture by ELISA, Western blotting, and mass spectrometry.ConclusionsSerum LRG1 was significantly elevated in women with ovarian cancer compared to healthy women and women with benign gynecological disease, and was only moderately correlated with CA125. Ovarian cancer cells secrete LRG1 and may contribute directly to the elevated levels of LRG1 observed in the serum of ovarian cancer patients. Future studies will determine whether LRG1 may serve as a biomarker for presurgical diagnosis, disease recurrence, and/or as a target for therapy.
Genetic and chemical modulation of spastin-dependent axon outgrowth in zebrafish embryos indicates a role for impaired microtubule dynamics in hereditary spastic paraplegia
Authors: Butler Richard , Wood Jonathan D. , Landers Jennifer A. , Cunliffe Vincent T. 
Published: September 2010

SUMMARY
Mutations in the SPAST (SPG4) gene, which encodes the microtubule-severing protein spastin, are the most common cause of autosomal dominant hereditary spastic paraplegia (HSP). Following on from previous work in our laboratory showing that spastin is required for axon outgrowth, we report here that the related microtubule-severing protein katanin is also required for axon outgrowth in vivo. Using confocal time-lapse imaging, we have identified requirements for spastin and katanin in maintaining normal axonal microtubule dynamics and growth cone motility in vivo, supporting a model in which microtubule severing is required for concerted growth of neuronal microtubules. Simultaneous knockdown of spastin and katanin caused a more severe phenotype than did individual knockdown of either gene, suggesting that they have different but related functions in supporting axon outgrowth. In addition, the microtubule-destabilising drug nocodazole abolished microtubule dynamics and growth cone motility, and enhanced phenotypic severity in spast-knockdown zebrafish embryos. Thus, disruption of microtubule dynamics might underlie neuronal dysfunction in this model, and this system could be used to identify compounds that modulate microtubule dynamics, some of which might have therapeutic potential in HSP.
Osteoblasts in bone tissue engineering
Authors: Jayakumar P , Di Silvio L 
Published: September 2010

Osteoblasts are integral to the development, growth, function, repair and maintenance of bone. The osteoblast forms organic, non-mineralized bone matrix and is involved in complex interactions with a variety of factors, mediators and cell types. Degeneration, pathology, and trauma cause disruption and destruction of the normal skeletal environment and may lead to bone loss. There is a rise in active populations involved in trauma, elderly patients with fragility fractures and an overall increase in primary, revision and reconstructive bone and joint surgery. Despite the rapid evolution of implant technologies and bone grafting techniques, there is still a great demand for novel bone replacement strategies. Bone tissue engineering is the state of the art science with the potential to regenerate bone with natural form and function. This review presents the biology of osteoblasts and their current applications in bone tissue engineering biotechnologies and role in stem cell, bioactive factor, recombinant signalling molecule and gene therapy research.
Structural capacity and the 20 MW wind turbine
Authors: Garvey S D 
Published: September 2010

This article addresses a generic and fundamental question: given the specification for a structure, how can one assess or even express its capacity without first designing it? The question is motivated by the consideration of how wind turbines (offshore wind turbines in particular) may scale up further. An underlying premise is that the wind-turbine designs that have evolved from 50 kW to 5 MW may warrant re-examination to check whether scaling effects demand new approaches at larger scales. Since several in the industry are already setting sights on 8 MW and even 10 MW machines as extrapolations of current designs, this article considers the development of a 20 MW (232 m diameter) machine. The conventional three-bladed arrangement on a slender tower is examined for notional 5 and 20 MW machines for similar rated wind conditions. Initially, the article considers the structural capacity requirements for conventional designs at both 5 and 20 MW and how these can be reduced substantially – using a floating framework in place of a tower and by deploying cable bracing on the rotor. When tower bending and the non-productive blade bending moments have thus been addressed, the turbine torque itself emerges as a major cause of cost. The turbine torque directly influences the costs of blades, pitch and yaw bearings, direct-drive generators (if present), gearbox (if present), and main shaft, and it is confirmed that in all cases, the total amounts of material required are at least proportional to the turbine torque for conventional designs. An alternative wind-turbine configuration is examined. In this, gravity is co-opted as an ally rather than an enemy, and power conversion takes place entirely within the rotor by allowing gravity to move bodies within the rotor. The concept is illustrated for a 20 MW machine and shown to be entirely workable in principle. A strong feature of this proposed new machine configuration is that the costs are almost exclusively structural and can be quantified in terms of the uniform currency of structural capacity. The scalability of this concept becomes clear by observing that the mean velocities of the moveable masses relative to the main rotor structure are virtually independent of machine scale.