bluuebunny/crossref_metadata_2025 huggingface dataset:
Electrochemical sensors, MTT and immunofluorescence assays for monitoring the proliferation effects of cissus populnea extracts on Sertoli cells
Authors: Osibote Elizabeth , Noah Naumih , Sadik Omowunmi , McGee Dennis , Ogunlesi Modupe
Published: May 2011

Background

We describe the development of an electrochemical sensor array for monitoring the proliferation effects of cissus populnea plant extracts on TM4 Sertoli cells.

Methods

The proliferation activities of the extracts on Sertoli cells were studied using a high-throughput electrochemical sensor array (DOX-96) and the analytical sensor characteristics were compared with conventional colorimetric MTT (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide) assay and fluorescence spectroscopy.

Results

This work shows that there is a definite positive trend in the proliferation effect of the extract of Cissus populnea on the TM4 Sertoli cells. All of the three techniques confirmed that the most effective concentration for the proliferation is 10 ppm. At this concentration, the proliferation effect was established around 120% for both DOX-96 and MTT techniques, whereas fluorescence assays showed a higher level (120-150%). DOX-96 showed a lower limit of detection (1.25 × 10(4) cells/ml); whereas the LOD recorded for both MTT and fluorescence techniques was 2.5 × 10(4) cells/ml. Visual examination of the cells by means of confocal fluorescence microscopy confirmed the proliferation of Sertoli cells as was determined using the MTT assay. This investigation provides a confident interpretation of the results and proved that the most effective concentration for the proliferation using Cissus populnea plant extract is 10 ppm.

Conclusions

Overall, the DOX results compared well with the conventional methods of checking proliferation of cells. The fascinating feature of the sensor array is the ability to provide continuous proliferation experiments with no additional reagents including 96 simultaneous electrochemical experiments. The use of the DOX-96 could reduce a typical bioassay time by 20-fold. Thus the DOX-96 can be used as both a research tool and for practical cell culture monitoring.
Inhibition of phosphorylated c-Met in rhabdomyosarcoma cell lines by a small molecule inhibitor SU11274
Authors: Hou Jinxuan , Dong Jixin , Sun Lijun , Geng Liying , Wang Jing , Zheng Jialin , Li Yan , Bridge Julia , Hinrichs Steven H , Ding Shi-Jian
Published: May 2011

Background

c-Met is a receptor tyrosine kinase (RTK) that is over-expressed in a variety of cancers and involved in cell growth, invasion, metastasis and angiogenesis. In this study, we investigated the role of c-Met in rhabdomyosarcoma (RMS) using its small molecule inhibitor SU11274, which has been hypothesized to be a potential therapeutic target for RMS.

Methods

The expression level of phosphorylated c-Met in RMS cell lines (RD, CW9019 and RH30) and tumor tissues was assessed by phospho-RTK array and immunohistochemistry, respectively. The inhibition effects of SU11274 on RMS cells were studied with regard to intracellular signaling, cell proliferation, cell cycle and cell migration.

Results

A high level of phosphorylated c-Met was detected in 2 alveolar RMS cell lines (CW9019 and RH30) and 14 out of 24 RMS tissue samples, whereas relatively low levels of phospho-c-Met were observed in the embryonic RMS cell line (RD). The small molecule SU11274 could significantly reduce the phosphorylation of c-Met, resulting in inhibition of cell proliferation, G1 phase arrest of cell cycle and blocking of cell migration in CW9019 and RH30 cell lines.

Conclusion

These results might support the role of c-Met in the development and progression of RMS. Furthermore, the inhibitor of c-Met, SU11274, could be an effective targeting therapy reagent for RMS, especially alveolar RMS.
Nanostructured hybrid ZnO thin films for energy conversion
Authors: Moya Mónica , Samantilleke Anura Priyajith , Mollar Miquel , Marí Bernabé
Published: May 2011

We report on hybrid films based on ZnO/organic dye prepared by electrodeposition using tetrasulfonated copper phthalocyanines (TS-CuPc) and Eosin-Y (EoY). Both the morphology and porosity of hybrid ZnO films are highly dependent on the type of dyes used in the synthesis. High photosensitivity was observed for ZnO/EoY films, while a very weak photoresponse was obtained for ZnO/TS-CuPc films. Despite a higher absorption coefficient of TS-CuPc than EoY, in ZnO/EoY hybrid films, the excited photoelectrons between the EoY levels can be extracted through ZnO, and the porosity of ZnO/EoY can also be controlled.
Carbon composite micro- and nano-tubes-based electrodes for detection of nucleic acids
Authors: Prasek Jan , Huska Dalibor , Jasek Ondrej , Zajickova Lenka , Trnkova Libuse , Adam Vojtech , Kizek Rene , Hubalek Jaromir
Published: May 2011

The first aim of this study was to fabricate vertically aligned multiwalled carbon nanotubes (MWCNTs). MWCNTs were successfully prepared by using plasma enhanced chemical vapour deposition. Further, three carbon composite electrodes with different content of carbon particles with various shapes and sizes were prepared and tested on measuring of nucleic acids. The dependences of adenine peak height on the concentration of nucleic acid sample were measured. Carbon composite electrode prepared from a mixture of glassy and spherical carbon powder and MWCNTs had the highest sensitivity to nucleic acids. Other interesting result is the fact that we were able to distinguish signals for all bases using this electrode.
Plasmonic propagations distances for interferometric surface plasmon resonance biosensing
Authors: Lepage Dominic , Carrier Dominic , Jiménez Alvaro , Beauvais Jacques , Dubowski Jan J
Published: May 2011

A surface plasmon resonance (SPR) scheme is proposed in which the local phase modulations of the coupled plasmons can interfere and yield phase-sensitive intensity modulations in the measured signal. The result is an increased traceability of the SPR shifts for biosensing applications. The main system limitation is the propagation distance of the coupled plasmon modes. This aspect is therefore studied for thin film microstructures operating in the visible and near-infrared spectral regions. The surface roughness of the substrate layer is examined for different dielectrics and deposition methods. The Au layer, on which the plasmonic modes are propagating and the biosensing occurs, is also examined. The surface roughness and dielectric values for various deposition rates of very thin Au films are measured. We also investigate an interferometric SPR setup where, due to the power flux transfer between plasmon modes, the specific choice of grating coupler can either decrease or increase the plasmon propagation length.
Water exercises and quality of life during pregnancy
Authors: Vallim Ana L , Osis Maria J , Cecatti José G , Baciuk Érica P , Silveira Carla , Cavalcante Sérgio R
Published: May 2011

Background

In Brazil, concern with the quality of life of pregnant women is one of the points emphasized in the Program for the Humanization of Prenatal Care and Childbirth launched in 2000. However, there are few references in the literature on the role of either land or water-based physical exercise on women's quality of life during pregnancy. The purpose of this study was to evaluate the effects of a physical exercise program of water aerobics on the quality of life (QOL) of sedentary pregnant women.

Methods

A comparative observational study involving sedentary low-risk pregnant women bearing a single fetus with gestational age less than 20 weeks at the time of admission to the study, who were receiving antenatal care at a public health service. One group of 35 women was given routine antenatal care, while another group of 31 women, in addition to receiving the same routine care as the first group, also participated in three classes of water aerobics per week. QOL was evaluated by applying the WHOQOL-BREF questionnaire in both groups at the 20th, 28th and 36th weeks of pregnancy. In the same occasions, women also answered another questionnaire about their experience with pregnancy and antenatal care.

Results

The great majority of the participants considered that the practice of water aerobics had benefitted them in some way. QOL scores were found to be high in both groups during follow-up. There was no association between the practice of water aerobics and QOL.

Conclusions

Further studies involving larger sample sizes should be conducted in different sociocultural contexts and/or using other instruments to adequately evaluate the QOL of women during pregnancy.
Oncogene addiction in gliomas: Implications for molecular targeted therapy
Authors: Yan Wei , Zhang Wei , Jiang Tao
Published: May 2011

Oncogene addiction is a phenomenon that the survival of cancer cells depends on an activated oncogene or inactivation of tumor suppressor gene, and is regarded as the 'Achilles heel' of the successful molecular targeted therapies in cancer. However, the role of oncogene addiction in gliomas has not been elucidated systematically. In this review, we summarize the current experimental and clinical evidence for the concept of oncogene addiction and describe the mechanisms explaining oncogene addiction in gliomas. And the clinical implications for oncogene addiction in molecular targeted therapy are further emphasized. In addition, we discuss future direction for defining complex "oncogene addiction network" through the integrated analysis of multiple platforms in the flow of genetic information in gliomagenesis.
ShRNA-mediated gene silencing of MTA1 influenced on protein expression of ER alpha, MMP-9, CyclinD1 and invasiveness, proliferation in breast cancer cell lines MDA-MB-231 and MCF-7 in vitro
Authors: Jiang Qingming , Zhang Hui , Zhang Ping
Published: May 2011

Background

MTA1(metastasis associated-1) is a tumor metastasis associated candidate gene and overexpression in many human tumors, including breast cancer. In this study, we investigated depressive effect on MTA1 by MTA1-specific short hairpin RNA(shRNA) expression plasmids in human breast cancer cell lines MDA-MB-231 and MCF-7, and effect on protein levels of ER alpha, MMP-9, cyclinD1, and tumor cell invasion, proliferation.

Methods

ShRNA expression vectors targeting MTA1 was constructed and transfected into human breast cancer cell lines MDA-MB-231 and MCF-7. The transfection efficiency was evaluated by fluorescence microscopy, mRNA levels of MTA1 were detected by reverse transcription-polymerase chain reaction (RT-PCR), protein levels of ER alpha, MMP-9 and cyclinD1 were detected by Western blotting, respectively. Tumor cells invasive ability were evaluated by Boyden chamber assay, the cells proliferation were evaluated using cell growth curve and MTT analysis, the cell cycle analysis was performed using flow cytometry.

Results

Down-regulation of MTA1 by RNAi approach led to re-expression of ER alpha in ER-negative breast cancer cell lines MDA-MB-231, and reduced protein levels of MMP-9 and CyclinD1, as well as decreased tumor cell invasion and proliferation, more cells were blocked in G0/G1 stage(P < 0.05). However, after inhibiting mRNA levels of MTA1, protein expression of ER alpha, MMP-9, cyclinD1 and the changes of cancer cells invasiveness, proliferation, cells cycle were no statistical difference in ER-positive human breast cancer cell lines MCF-7 (P > 0.05).

Conclusions

ShRNA targeted against MTA1 could specifically mediate the MTA1 gene silencing and consequentially recover the protein expression of ER alpha, resulting in increase sensitivity of antiestrogens, as well as suppress the protein levels of MMP-9 and cyclinD1 in ER-negative human breast cancer cell lines MDA-MB-231. Silencing effect of MTA1 could efficiently inhibit the invasion and proliferation in MDA-MB-231 cells. The shRNA interference targeted against MTA1 may have potential therapeutic utility in human breast cancer.
HIV and incarceration: prisons and detention
Authors: Jürgens Ralf , Nowak Manfred , Day Marcus
Published: May 2011

The high prevalence of HIV infection among prisoners and pre‐trial detainees, combined with overcrowding and sub‐standard living conditions sometimes amounting to inhuman or degrading treatment in violation of international law, make prisons and other detention centres a high risk environment for the transmission of HIV. Ultimately, this contributes to HIV epidemics in the communities to which prisoners return upon their release.

We reviewed the evidence regarding HIV prevalence, risk behaviours and transmission in prisons. We also reviewed evidence of the effectiveness of interventions and approaches to reduce the risk behaviours and, consequently, HIV transmission in prisons.

A large number of studies report high levels of risk behaviour in prisons, and HIV transmission has been documented. There is a large body of evidence from countries around the world of what prison systems can do to prevent HIV transmission. In particular, condom distribution programmes, accompanied by measures to prevent the occurrence of rape and other forms of non‐consensual sex, needle and syringe programmes and opioid substitution therapies, have proven effective at reducing HIV risk behaviours in a wide range of prison environments without resulting in negative consequences for the health of prison staff or prisoners.

The introduction of these programmes in prisons is therefore warranted as part of comprehensive programmes to address HIV in prisons, including HIV education, voluntary HIV testing and counselling, and provision of antiretroviral treatment for HIV‐positive prisoners. In addition, however, action to reduce overcrowding and improve conditions in detention is urgently needed.
Selected papers from the 13th Annual Bio-Ontologies Special Interest Group Meeting
Authors: Soldatova Larisa N , Sansone Susanna-Assunta , Stephens Susie M , Shah Nigam H
Published: May 2011

Over the years, the Bio-Ontologies SIG at ISMB has provided a forum for discussion of the latest and most innovative research in the application of ontologies and more generally the organisation, presentation and dissemination of knowledge in biomedicine and the life sciences. The ten papers selected for this supplement are extended versions of the original papers presented at the 2010 SIG. The papers span a wide range of topics including practical solutions for data and knowledge integration for translational medicine, hypothesis based querying , understanding kidney and urinary pathways, mining the pharmacogenomics literature; theoretical research into the orthogonality of biomedical ontologies, the representation of diseases, the representation of research hypotheses, the combination of ontologies and natural language processing for an annotation framework, the generation of textual definitions, and the discovery of gene interaction networks.
The Translational Medicine Ontology and Knowledge Base: driving personalized medicine by bridging the gap between bench and bedside
Authors: Luciano Joanne S , Andersson Bosse , Batchelor Colin , Bodenreider Olivier , Clark Tim , Denney Christine K , Domarew Christopher , Gambet Thomas , Harland Lee , Jentzsch Anja , Kashyap Vipul , Kos Peter , Kozlovsky Julia , Lebo Timothy , Marshall Scott M , McCusker Jamie P , McGuinness Deborah L , Ogbuji Chimezie , Pichler Elgar , Powers Robert L , Prud’hommeaux Eric , Samwald Matthias , Schriml Lynn , Tonellato Peter J , Whetzel Patricia L , Zhao Jun , Stephens Susie , Dumontier Michel
Published: May 2011

Background

Translational medicine requires the integration of knowledge using heterogeneous data from health care to the life sciences. Here, we describe a collaborative effort to produce a prototype Translational Medicine Knowledge Base (TMKB) capable of answering questions relating to clinical practice and pharmaceutical drug discovery.

Results

We developed the Translational Medicine Ontology (TMO) as a unifying ontology to integrate chemical, genomic and proteomic data with disease, treatment, and electronic health records. We demonstrate the use of Semantic Web technologies in the integration of patient and biomedical data, and reveal how such a knowledge base can aid physicians in providing tailored patient care and facilitate the recruitment of patients into active clinical trials. Thus, patients, physicians and researchers may explore the knowledge base to better understand therapeutic options, efficacy, and mechanisms of action.

Conclusions

This work takes an important step in using Semantic Web technologies to facilitate integration of relevant, distributed, external sources and progress towards a computational platform to support personalized medicine.

Availability

TMO can be downloaded from http://code.google.com/p/translationalmedicineontology and TMKB can be accessed at http://tm.semanticscience.org/sparql.
An open annotation ontology for science on web 3.0
Authors: Ciccarese Paolo , Ocana Marco , Garcia Castro Leyla Jael , Das Sudeshna , Clark Tim
Published: May 2011

Background

There is currently a gap between the rich and expressive collection of published biomedical ontologies, and the natural language expression of biomedical papers consumed on a daily basis by scientific researchers. The purpose of this paper is to provide an open, shareable structure for dynamic integration of biomedical domain ontologies with the scientific document, in the form of an Annotation Ontology (AO), thus closing this gap and enabling application of formal biomedical ontologies directly to the literature as it emerges.

Methods

Initial requirements for AO were elicited by analysis of integration needs between biomedical web communities, and of needs for representing and integrating results of biomedical text mining. Analysis of strengths and weaknesses of previous efforts in this area was also performed. A series of increasingly refined annotation tools were then developed along with a metadata model in OWL, and deployed for feedback and additional requirements the ontology to users at a major pharmaceutical company and a major academic center. Further requirements and critiques of the model were also elicited through discussions with many colleagues and incorporated into the work.

Results

This paper presents Annotation Ontology (AO), an open ontology in OWL-DL for annotating scientific documents on the web. AO supports both human and algorithmic content annotation. It enables “stand-off” or independent metadata anchored to specific positions in a web document by any one of several methods. In AO, the document may be annotated but is not required to be under update control of the annotator. AO contains a provenance model to support versioning, and a set model for specifying groups and containers of annotation. AO is freely available under open source license at http://purl.org/ao/, and extensive documentation including screencasts is available on AO’s Google Code page: http://code.google.com/p/annotation-ontology/ .

Conclusions

The Annotation Ontology meets critical requirements for an open, freely shareable model in OWL, of annotation metadata created against scientific documents on the Web. We believe AO can become a very useful common model for annotation metadata on Web documents, and will enable biomedical domain ontologies to be used quite widely to annotate the scientific literature. Potential collaborators and those with new relevant use cases are invited to contact the authors.
Automating generation of textual class definitions from OWL to English
Authors: Stevens Robert , Malone James , Williams Sandra , Power Richard , Third Allan
Published: May 2011

Background

Text definitions for entities within bio-ontologies are a cornerstone of the effort to gain a consensus in understanding and usage of those ontologies. Writing these definitions is, however, a considerable effort and there is often a lag between specification of the main part of an ontology (logical descriptions and definitions of entities) and the development of the text-based definitions. The goal of natural language generation (NLG) from ontologies is to take the logical description of entities and generate fluent natural language. The application described here uses NLG to automatically provide text-based definitions from an ontology that has logical descriptions of its entities, so avoiding the bottleneck of authoring these definitions by hand.

Results

To produce the descriptions, the program collects all the axioms relating to a given entity, groups them according to common structure, realises each group through an English sentence, and assembles the resulting sentences into a paragraph, to form as ‘coherent’ a text as possible without human intervention. Sentence generation is accomplished using a generic grammar based on logical patterns in OWL, together with a lexicon for realising atomic entities. We have tested our output for the Experimental Factor Ontology (EFO) using a simple survey strategy to explore the fluency of the generated text and how well it conveys the underlying axiomatisation. Two rounds of survey and improvement show that overall the generated English definitions are found to convey the intended meaning of the axiomatisation in a satisfactory manner. The surveys also suggested that one form of generated English will not be universally liked; that intrusion of too much ‘formal ontology’ was not liked; and that too much explicit exposure of OWL semantics was also not liked.

Conclusions

Our prototype tools can generate reasonable paragraphs of English text that can act as definitions. The definitions were found acceptable by our survey and, as a result, the developers of EFO are sufficiently satisfied with the output that the generated definitions have been incorporated into EFO. Whilst not a substitute for hand-written textual definitions, our generated definitions are a useful starting point.

Availability

An on-line version of the NLG text definition tool can be found at http://swat.open.ac.uk/tools/. The questionaire and sample generated text definitions may be found at http://mcs.open.ac.uk/nlg/SWAT/bio-ontologies.html.
Nociceptive tolerance is improved by bradykinin receptor B1 antagonism and joint morphology is protected by both endothelin type A and bradykinin receptor B1 antagonism in a surgical model of osteoarthritis
Authors: Kaufman Gabriel N , Zaouter Charlotte , Valteau Barthélémy , Sirois Pierre , Moldovan Florina
Published: May 2011

Introduction

Endothelin-1, a vasoconstrictor peptide, influences cartilage metabolism mainly via endothelin receptor type A (ETA). Along with the inflammatory nonapeptide vasodilator bradykinin (BK), which acts via bradykinin receptor B1 (BKB1) in chronic inflammatory conditions, these vasoactive factors potentiate joint pain and inflammation. We describe a preclinical study of the efficacy of treatment of surgically induced osteoarthritis with ETA and/or BKB1 specific peptide antagonists. We hypothesize that antagonism of both receptors will diminish osteoarthritis progress and articular nociception in a synergistic manner.

Methods

Osteoarthritis was surgically induced in male rats by transection of the right anterior cruciate ligament. Animals were subsequently treated with weekly intra-articular injections of specific peptide antagonists of ETA and/or BKB1. Hind limb nociception was measured by static weight bearing biweekly for two months post-operatively. Post-mortem, right knee joints were analyzed radiologically by X-ray and magnetic resonance, and histologically by the OARSI histopathology assessment system.

Results

Single local BKB1 antagonist treatment diminished overall hind limb nociception, and accelerated post-operative recovery after disease induction. Both ETA and/or BKB1 antagonist treatments protected joint radiomorphology and histomorphology. Dual ETA/BKB1 antagonism was slightly more protective, as measured by radiology and histology.

Conclusions

BKB1 antagonism improves nociceptive tolerance, and both ETA and/or BKB1 antagonism prevents joint cartilage degradation in a surgical model of osteoarthritis. Therefore, they represent a novel therapeutic strategy: specific receptor antagonism may prove beneficial in disease management.
Diagnostic Imaging and Biopsy Use Among Elderly Medicare Beneficiaries With Hepatocellular Carcinoma
Authors: Massarweh Nader N. , Park James O. , Bruix Jordi , Yeung Raymond S.W. , Etzioni Ruth B. , Symons Rebecca Gaston , Baldwin Laura-Mae , Flum David R.
Published: May 2011

Understanding the factors that drive biopsy use may help improve the care of patients with hepatocellular carcinoma.
Spanish As a Primary Language and Its Effect on Breast Cancer Presentation
Authors: Oliveira Kristin , Clark Steven , Dunn Ernest , Mangram Alicia
Published: May 2011

In the authors' patient population, non–English-speaking Hispanic patients presented at more advanced stages than their English-speaking counterparts.
Current Hepatitis B Screening Practices and Clinical Experience of Reactivation in Patients Undergoing Chemotherapy for Solid Tumors: A Nationwide Survey of Medical Oncologists
Authors: Day Fiona L. , Link Emma , Thursky Karin , Rischin Danny
Published: May 2011

Universal screening for chronic hepatitis B virus before chemotherapy has been recommended by the Centers for Disease Control, but the majority of Australian medical oncologists have not adopted the practice.
A Screening Tool to Enhance Clinical Trial Participation at a Community Center Involved in a Radiation Oncology Disparities Program
Authors: Proctor Julian W. , Martz Elaine , Schenken Larry L. , Rainville Rebecca , Marlowe Ursula
Published: May 2011

A simple screening tool was used to enhance clinical trial participation at a community radiation oncology center involved in a National Cancer Institute–funded disparities program but lacking on site clinical trials personnel.
Barriers to Recruitment of Rural Patients in Cancer Clinical Trials
Authors: Virani Shamsuddin , Burke Lola , Remick Scot C. , Abraham Jame
Published: May 2011

Rates of clinical trial participation are lower among patients in rural areas. Oncologists should be trained to address patient concerns regarding clinical trial availability, utility, and accessibility.
National Cancer Institute Conference on Treating Tobacco Dependence at Cancer Centers
Authors: Morgan Glen , Schnoll Robert A. , Alfano Catherine M. , Evans Sarah E. , Goldstein Adam , Ostroff Jamie , Park Elyse Richelle , Sarna Linda , Cox Lisa Sanderson
Published: May 2011

The National Cancer Institute cancer centers possess the credibility to help smokers quit. With the greater life expectancies forecast for patients with cancer, addressing smoking at cancer centers has taken on greater importance.
The Clinical Research Team
Authors: Baer Allison R. , Zon Robin , Devine Susan , Lyss Alan P.
Published: May 2011

Developing and maintaining an exemplary research team is essential to the success of a quality clinical research program.
Health Technology Assessment and Private Payers' Coverage of Personalized Medicine
Authors: Trosman Julia R. , Van Bebber Stephanie L. , Phillips Kathryn A.
Published: May 2011

A study of major US private payers showed an important role and considerable shortcomings of external health technology assessment in coverage decisions on personalized medicine.
Characterizing Medical Care by Disease Phase in Metastatic Colorectal Cancer
Authors: Song Xue , Zhao Zhongyun , Barber Beth , Gregory Christopher , Schutt David , Gao Sue
Published: May 2011

This study characterized patterns and costs of medical care by disease phase in patients with newly diagnosed mCRC using a large US national commercially insured claims database.
Pathways, Outcomes, and Costs in Colon Cancer: Retrospective Evaluations in Two Distinct Databases
Authors: Hoverman J. Russell , Cartwright Thomas H. , Patt Debra A. , Espirito Janet L. , Clayton Matthew P. , Garey Jody S. , Kopp Terrance J. , Kolodziej Michael , Neubauer Marcus A. , Fitch Kathryn , Pyenson Bruce , Beveridge Roy A.
Published: May 2011

Retrospective evaluations of electronic health records and claims databases to assess clinical outcomes and costs associated with evidence-based pathways in colon cancer.
Pregnancy-Associated Plasma Protein-A2 (PAPP-A2): Tissue Expression and Biological Consequences of Gene Knockout in Mice
Authors: Conover Cheryl A. , Boldt Henning B. , Bale Laurie K. , Clifton Kari B. , Grell Jacquelyn A. , Mader Jessica R. , Mason Emily J. , Powell David R.
Published: May 2011

Pregnancy-associated plasma protein-A2 (PAPP-A2) is a novel homolog of PAPP-A in the metzincin superfamily. However, compared with the accumulating data on PAPP-A, very little is known about PAPP-A2. In this study, we determined the tissue expression pattern of PAPP-A2 mRNA in wild-type (WT) mice and characterized the phenotype of mice with global PAPP-A2 deficiency. Tissues expressing PAPP-A2 in WT mice were more limited than those expressing PAPP-A. The highest PAPP-A2 mRNA expression was found in the placenta, with abundant expression in fetal, skeletal, and reproductive tissues. Heterozygous breeding produced the expected Mendelian distribution for the pappa2 gene and viable homozygous PAPP-A2 knockout (KO) mice that were normal size at birth. The most striking phenotype of the PAPP-A2 KO mouse was postnatal growth retardation. Male and female PAPP-A2 KO mice had 10 and 25–30% lower body weight, respectively, than WT littermates. Adult femur and body length were also reduced in PAPP-A2 KO mice, but without significant effects on bone mineral density. PAPP-A2 KO mice were fertile, but with compromised fecundity. PAPP-A expression was not altered to compensate for the loss of PAPP-A2 expression, and proteolysis of PAPP-A2's primary substrate, IGF-binding protein-5, was not altered in fibroblasts from PAPP-A2 KO embryos. In conclusion, tissue expression patterns and biological consequences of gene KO indicate distinct physiological roles for PAPP-A2 and PAPP-A in mice.
Wild-Type p53 Attenuates Cancer Cell Motility by Inducing Growth Differentiation Factor-15 Expression
Authors: Cheng Jung-Chien , Chang Hsun-Ming , Leung Peter C. K.
Published: May 2011

A major function of the p53 tumor suppressor is the regulation of the cell cycle and apoptosis. In addition to its well-documented functions in malignant cancer cells, p53 can also regulate cell migration and invasion, which contribute to metastasis. Growth differentiation factor-15 (GDF-15), a member of the TGF-β superfamily, has been shown to be a downstream target of p53 and is associated with diverse human diseases and cancer progression. In this study, we examined the potential role of GDF-15 in p53-regulated cancer cell motility. We show that overexpression of wild-type p53 in two highly invasive p53-null human cancer cell lines, SKOV3 and PC3, attenuated cell migration and the movement through Matrigel. Using wild-type p53 and DNA-binding-deficient p53 mutants, we found that the transcriptional activity of p53 is required in the induction of GDF-15 expression. Cell movement through uncoated and Matrigel-coated transwell decreased in response to treatment with recombinant GDF-15, whereas the cell proliferation was not affected by GDF-15 treatment. Moreover, the induction of GDF-15 expression and secretion by p53 and the reduction in cell movement through Matrigel were diminished by treatment with GDF-15 small interfering RNA. This study demonstrates a mechanism by which p53 attenuates cancer cell motility through GDF-15 expression. In addition, our results indicate that GDF-15 mediates the functions of p53 by autocrine/paracrine action.
Steroidogenic Factor-1 Is Required for TGF-β3-Mediated 17β-Estradiol Synthesis in Mouse Ovarian Granulosa Cells
Authors: Liang Ning , Xu Yinglei , Yin Yimeng , Yao Guidong , Tian Hui , Wang Guishuan , Lian Jie , Wang Yong , Sun Fei
Published: May 2011

The TGF-β superfamily members are indicated to play key roles in ovarian follicular development, such as granulosa cell proliferation, estrogens, and progesterone production. However, little is known about the roles of TGF-β3 in follicular development. In this study, we found that TGF-β3 was predominantly expressed in granulosa cells of mouse ovarian follicles, and it significantly promoted 17β-estradiol (E2) release in a dose-dependent manner. The orphan nuclear receptor steroidogenic factor-1 (SF-1) was required in TGF-β3-induced Cyp19a1 (a key rate-limiting enzyme for estrogen biosynthesis) expression and E2 release. Additionally, TGF-β3 enhanced the binding of SF-1 to endogenous ovary-specific Cyp19a1 type II promoter, as evidenced by chromatin immunoprecipitation assays. The enhanced effect of SF-1 by TGF-β3 may be mediated through functional interactions between SF-1 and mothers against decapentaplegic homolog (Smad)3 (a mediator of TGF-β signaling pathway), because disruption of the interaction abolished the synergistic effects of SF-1, Smad3, and TGF-β3 on Cyp19a1 mRNA expression. RNA interference and chromatin immunoprecipitation studies also demonstrated that Smad3 was required for SF-1 binding to Cyp19a1 type II promoter and activation of Cyp19a1. Smad3 thus acts as a point of convergence that involves integration of SF-1 and TGF-β signaling in affecting E2 production. Taken together, our data provide mechanistic insights into the roles of SF-1 in TGF-β3-mediated E2 synthesis. Understanding of potential cross-points between extracellular signals affecting estrogen production will help to discover new therapeutic targets in estrogen-related diseases.
High-Yield Expression of a Catalytically Active Membrane-Bound Protein: Human P450 Oxidoreductase
Authors: Sandee Duanpen , Miller Walter L.
Published: May 2011

P450 oxidoreductase (POR) is a two-flavin protein that reduces microsomal P450 enzymes and some other proteins. Preparation of active bacterially expressed human POR for biochemical studies has been difficult because membrane-bound proteins tend to interact with column matrices. To reduce column-protein interactions and permit more vigorous washing, human POR lacking 27 N-terminal residues (N-27 POR) was modified to carry a C-terminal Gly3His6-tag (N-27 POR-G3H6). When expressed in Escherichia coli, N-27 POR-G3H6 could be purified to apparent homogeneity by a modified, single-step nickel-nitrilotriacetic acid affinity chromatography, yielding 31 mg POR per liter of culture, whereas standard purification of native N-27 POR required multiple steps, yielding 5 mg POR per liter. Both POR proteins had absorption maxima at 375 and 453 nm and both reduced cytochrome c with indistinguishable specific activities. Using progesterone as substrate for bacterially expressed purified human P450c17, the Michaelis constant for 17α-hydroxylase activity supported by N-27 POR or N-27 POR-G3H6 were 1.73 or 1.49 μm, and the maximal velocity was 0.029 or 0.026 pmol steroids per picomole P450 per minute, respectively. Using 17-hydroxypregnenolone as the P450c17 substrate, the Michaelis constant for 17,20 lyase activity using N-27 POR or N-27 POR-G3H6 was 1.92 or 1.89 μm and the maximal velocity was 0.041 or 0.042 pmol steroid per picomole P450 per minute, respectively. Thus, N-27 POR-G3H6 is equally active as native N-27 POR. This expression and purification system permits the rapid preparation of large amounts of highly pure, biologically active POR and may be generally applicable for the preparation of membrane-bound proteins.
The Role of Sonic Hedgehog-Gli2 Pathway in the Masculinization of External Genitalia
Authors: Miyagawa Shinichi , Matsumaru Daisuke , Murashima Aki , Omori Akiko , Satoh Yoshihiko , Haraguchi Ryuma , Motoyama Jun , Iguchi Taisen , Nakagata Naomi , Hui Chi-chung , Yamada Gen
Published: May 2011

During embryogenesis, sexually dimorphic organogenesis is achieved by hormones produced in the gonad. The external genitalia develop from a single primordium, the genital tubercle, and their masculinization processes depend on the androgen signaling. In addition to such hormonal signaling, the involvement of nongonadal and locally produced masculinization factors has been unclear. To elucidate the mechanisms of the sexually dimorphic development of the external genitalia, series of conditional mutant mouse analyses were performed using several mutant alleles, particularly focusing on the role of hedgehog signaling pathway in this manuscript. We demonstrate that hedgehog pathway is indispensable for the establishment of male external genitalia characteristics. Sonic hedgehog is expressed in the urethral plate epithelium, and its signal is mediated through glioblastoma 2 (Gli2) in the mesenchyme. The expression level of the sexually dimorphic genes is decreased in the glioblastoma 2 mutant embryos, suggesting that hedgehog signal is likely to facilitate the masculinization processes by affecting the androgen responsiveness. In addition, a conditional mutation of Sonic hedgehog at the sexual differentiation stage leads to abnormal male external genitalia development. The current study identified hedgehog signaling pathway as a key factor not only for initial development but also for sexually dimorphic development of the external genitalia in coordination with androgen signaling.
The Chapter Left Untold: Labor Historians and the Problem of Union Corruption
Authors: Witwer David
Published: May 2011

This issue's Up for Debate section features a lively exchange of responses by four scholars to David Witwer on the subject of labor historians and the problem of union corruption. Highlighting an extended but uneven literature on the subject stretching back to Commons-School practitioners, Witwer tweaks recent-day labor historians for turning away from close examination of the underside of labor movements—a side that antilabor political forces have been all too eager to manipulate to their advantage. A distinguished group of respondents—Andrew Wender Cohen, Rosemary Feuer, Joshua Freeman, and Jennifer Luff—receive his message with a mixture of appreciation, discomfort, and veiled criticism.
Italian Militants and Migrants and the Language of Solidarity in the Early-Twentieth-Century Western Coalfields
Authors: Brier Stephen , Fasce Ferdinando
Published: May 2011

This article explores the largely unknown world of militant Italian labor organizers and the rank-and-file Italian immigrants they led in labor struggles in the western coalfields of the United States in the early twentieth century. Building on the recent “transnational turn” in immigration scholarship and employing a close reading of an important Italian-language newspaper, Il Lavoratore Italiano; official Italian consular records and police archives; and previously unused American federal and state prison records, the authors analyze the ways immigrant workers and their immigrant radical leaders (focusing especially on Carlo Demolli, a United Mine Workers of America and Western Federation of Miners organizer and newspaper editor from northern Italy) launched intense labor actions in these years. The language of Italian solidarity that emerges from these sources helped a militant ethnic minority of Italian migrants sustain a major six-month strike in 1903–4 that crossed local, regional, national, and transnational material and symbolic boundaries, despite intense legal and military opposition from coal operators and the aligned forces of local, state, and U.S. officials and Italian consular officers.
Race, Respect, and Authority in Contemporary Brazil: Interpreting the Stories of Sugarcane Workers
Authors: Rogers Thomas D.
Published: May 2011

This article draws primarily on interviews with two union leaders from the sugarcane region of the northeastern Brazilian state of Pernambuco to demonstrate the role of race in their experiences over the past forty years as well as how they navigated and interpreted questions of authority, respect, and conflict in a landscape marked by frequently rigid conceptions of hierarchy. The article analyzes particular stories these men told and describes the background to their storytelling. It places the interviews with the two leaders in the context of a larger chorus of cane workers' voices from the region, testimonies that are crucially valuable sources for understanding what remains a largely oral culture. They provide answers to questions on topics that would otherwise remain outside the reach of historians, from the complexities of class relations and the dynamics of conflict to such subtle issues as slavery's legacies. The article approaches these issues in three sections: the first charts the two leaders' lives in the context of the cane zone's history; the second addresses race and respect; and the third discusses violence, voice, and authority.
Identification of an animal sucrose transporter
Authors: Meyer Heiko , Vitavska Olga , Wieczorek Helmut
Published: May 2011

According to a classic tenet, sugar transport across animal membranes is restricted to monosaccharides. Here, we present the first report of an animal sucrose transporter, SCRT, which we detected in Drosophila melanogaster at each developmental stage. We localized the protein in apical membranes of the late embryonic hindgut as well as in vesicular membranes of ovarian follicle cells. The fact that knockdown of SCRT expression results in significantly increased lethality demonstrates an essential function for the protein. Experiments with Saccharomyces cerevisiae as a heterologous expression system revealed that sucrose is a transported substrate. Because the knockout of SLC45A2, a highly similar protein belonging to the mammalian solute carrier family 45 (SLC45) causes oculocutaneous albinism and because the vesicular structures in which SCRT is located appear to contain melanin, we propose that these organelles are melanosome-like structures and that the transporter is necessary for balancing the osmotic equilibrium during the polymerization process of melanin by the import of a compatible osmolyte. In the hindgut epithelial cells, sucrose might also serve as a compatible osmolyte, but we cannot exclude the possibility that transport of this disaccharide also serves nutritional adequacy.
Feasibility of dual gradient-echo in-phase and opposed-phase magnetic resonance imaging for the evaluation of epicardial fat
Authors: Okayama Satoshi , Ayako Seno , Somekawa Satoshi , Uemura Shiro , Kubota Yasushi , Saito Yoshihiko
Published: May 2011

Background

Dual gradient-echo in-phase (IP) and opposed-phase (OP) magnetic resonance imaging (MRI) can evaluate small amounts of fat, and is widely used for imaging abdominal organs. Epicardial fat has recently been revealed as having an important role in the development of heart disease, but IPOP-MRI has not been widely applied in this field, probably because of cardiac motion artifacts.

Purpose

To demonstrate the feasibility of IPOP-MRI with electrocardiography (ECG)-gating for evaluation of epicardial fat in the normal human heart, compared to black-blood T1-weighted imaging (T1WI).

Material and Methods

Ten healthy volunteers were studied. Epicardial fat volume was quantitatively evaluated on OP-from-IP subtraction images and T1-weighted images.

Results

Epicardial fat was clearly visualized on the subtraction images as hyperintense areas that corresponded to regions identified as epicardial fat on the T1-weighted images. Epicardial fat volume correlated well between the two methods (r = 0.93, P <0.0001), and tended to be larger on the subtraction images than on the T1-weighted images (91.4 ± 30.1 vs. 84.1 ± 30.5 mL, P = 0.07).

Conclusion

IPOP-MRI with ECG-gating may be a useful alternative method to black-blood T1WI for evaluation of epicardial fat.
Diffusion tensor imaging of prostate at 3.0 Tesla
Authors: Li Chunmei , Chen Min , Li Saying , Zhao Xuna , Zhang Chen , Liu Ming , Zhou Cheng
Published: May 2011

Background

The feasibility of diffusion tensor imaging (DTI) of prostate has been confirmed by several studies. Apparent diffusion coefficient (ADC) and fractional anisotropy (FA) values of prostate with healthy or pathological changes remain controversial.

Purpose

To investigate the efficacy of DTI at 3.0 T in diagnosing prostate cancer in the peripheral zone and to determine the normative ADC and FA values of the normal prostate.

Material and Methods

T2-weighted imaging (T2WI) and DTI of the prostate was performed in 33 cases with diagnosis confirmed by biopsy at 3.0 T MR. ADC and FA values of cancerous and non-cancerous sextants were compared. Receiver-operating characteristic (ROC) curves were used to compare the ability of ADC, FA and the two values combined in diagnosing prostate cancer in the peripheral zone. DTI data of 20 healthy young volunteers were also acquired. ADC and FA values of the normal central gland and the peripheral zone were compared.

Results

ADC value (1.10 ± 0.09 × 10−3 mm2/s) was lower while FA value (0.37 ± 0.05) was higher in normal central gland, compared with that in normal peripheral zone (1.63 ± 0.15 × 10−3 mm2/s, 0.21 ± 0.07, respectively) ( P < 0.0001, P < 0.0001, respectively). Sixteen of 33 cases were confirmed to be malignant while 17 of 33 cases were benign. All the 198 sextants were confirmed by biopsy, including 136 non-cancerous sextants and 62 cancerous sextants. There were significant differences between cancerous sextants (1.02 ± 0.16 × 10−3 mm2/s, 0.38 ± 0.09) and non-cancerous sextants (1.22 ± 0.14 × 10−3 mm2/s, 0.31 ± 0.06) for both ADC and FA values ( P <0.0001, P <0.0001, respectively). Significant differences were noted between the AUC of DTI and FA alone (0.86 vs. 0.76, P = 0.0009), but no differences between the AUC of DTI and ADC alone (0.86 vs. 0.84, P = 0.1595).

Conclusion

ADC and FA values of normal prostate may be compatible with the microstructural organization of prostate. Furthermore, DTI may be a potential tool in diagnosing prostate cancer in the peripheral zone.
Risk factors associated with breast arterial calcifications
Authors: Ilica Ahmet Turan , Aydogan Umit , Guvenc Inanc , Cayci Tuncer , Oren Cem , Onar Tamer , Ugurel Sahin , Saglam Kenan
Published: May 2011

Background

A number of studies have linked the presence of breast arterial calcifications (BACs) with an increased risk of diabetes, hypertension, coronary artery disease (CAD), and cardiovascular mortality. Because there is a well-established screening system for breast cancer, it has been proposed that the presence of BACs can be used as a warning sign indicating an increased risk of metabolic and vascular diseases.

Purpose

To determine the relation between BAC and early renal dysfunction.

Material and Methods

A retrospective review of 6118 mammograms identified 701 cases with BACs. Women with BACs were compared to a random selection of 362 women without BACs based on available laboratory data. Univariate analysis was conducted according to age groups.

Results

The prevalence of BACs was 11.5% in our study. Hyperglycemia increased the odds of BACs by 8.1 (95% CI 3.0–22.1, P < 0.001) in the 50–59-year age group. The presence of an elevated blood urea nitrogen (BUN) and serum creatinine increased the odds of BACs by 2.6 (95% CI 1.2–6.0, P = 0.016) and 2.3 (95% CI 1.0–5.2, P = 0.045) in women ≥70 years of age. Hyperlipidemia was not a significant risk factor for BACs in any age group.

Conclusion

Our results support the view that the presence of BACs on mammography may be indicative of diabetes in middle-aged women. On the other hand, BACs are not very useful for predicting early renal dysfunction in women <70 years of age.