bluuebunny/crossref_metadata_2025 huggingface dataset:
Essential Work of Fracture Evaluation of Compression-Molded Polypropylene/Ethylene and 1-Octene Copolymer Blends
Authors: Wang Lei , Xie Bang-Hu , Yang Wei , Shen Yue-Xin , Yang Ming-Bo
Published: December 2009

The influence of ethylene and 1-octene copolymer content on the fracture behavior of compression-molded polypropylene/copolymer of ethylene and 1-octene blends was evaluated by means of the essential work of fracture method. The results indicated that the approach worked well for the polypropylene/copolymer of ethylene and 1-octene blends when copolymer of ethylene and 1-octene content was 0∼7.5 wt%. The specific essential work of fracture (we) of the blends increased with increasing copolymer of ethylene and 1-octene content and the dominant factor which affected we was the necking and subsequent fracture term (we,n). The specific non-essential work of fracture (βwp) slightly increased with increasing copolymer of ethylene and 1-octene content, while the term wp showed a decreasing trend with increasing shape factor (β). The trend of w e values obtained from crack-opening displacement was similar to that of essential work of fracture tests.
The Impact and Tribological Properties of PTFE Composites Filled with PA6
Authors: Li J.
Published: December 2009

Blending polytetrafluoroethylene (PTFE) and polyamide-6 (PA6) at different compositions was produced in a corotating twin screw extruder, where PTFE acts as the polymer matrix and PA6 as the dispersed phase. The effects of PA6 content on impact and tribological properties of the composites were investigated. The worn surface morphologies of neat PTFE and its composites were examined by scanning electron microscopy and the wear mechanisms were discussed. The presence of PA6 particles dispersed in the PTFE continuous phase exhibited superior tribological characteristics to unfilled PTFE. The optimum wear reduction was obtained when the content of PA6 was 30 vol%.
The Use of Goal Attainment Scaling to Facilitate and Assess Individualized Change in a Wellness Intervention for Women With Fibromyalgia Syndrome
Authors: Becker Heather , Stuifbergen Alexa , Taxis Carole , Beal Claudia C. , Pierini Diana M.
Published: December 2009

Purpose: The authors examined goal achievement over an 8-month period in women with fibromyalgia participating in a holistic health promotion intervention using Goal Attainment Scaling. Design: Descriptive. Methods: Goal attainment was assessed by interviews at five points: baseline (retrospectively), immediately after the 8-week classes, at the middle and end of the telephone support period, and 3 months later. Findings: The percentage of women who attained or exceeded their goals in the four health promotion areas of Lifestyle Adjustment, Physical Activity, Nutrition, and Stress Management increased from between 15% and 26% at the end of the classes to between 58% and 76% at the end of the telephone support period. Although scores declined somewhat in the following 3 months, at least 60% of the women continued to report behaviors at or above their goal level in all areas except Physical Activity. Conclusions: Goal Attainment Scaling, an individually determined measure of change, can effectively capture behavioral changes associated with a holistic health promotion intervention. A nurse facilitator, who not only understood the need for specific, measurable GAS but was also able to encourage and support women’s identification of goals that were meaningful to them, was key to the positive findings observed here.
Reflection of a 7-Year Patient Care Program
Authors: Ernst Lorraine S. , Ferrer Lynn
Published: December 2009

Integrative alternative therapies, also known as holistic therapies, have many applications in hospitals and health centers. These may include relaxation therapies, meditation, massage, reflexology, and Reiki or healing touch. Patients today are looking for these services, and institutions continue to explore ways to provide them without affecting their bottom line. The Integrative Cardiac Wellness Program is such a service, and its growth and longevity comes out of the personal investment of the staff to the program and to their patients. The literature review on the permanence of caring practice shows that caring about your work with patients, not just the job, is critical in longevity (Graber & Mitcham, 2004). The holistic nurses’ and staff ’s commitment to their professional growth within their specialty and their personal spiritual practice as experts in the field forms the backbone of the Integrative Wellness Program’s success. It has been in existence for 7 years, providing integrative healing therapies to more than 7,000 patients, making it one of the most experienced. The program now serves cardiac surgery patients, and patients who have been diagnosed with cancer.
Older People’s Experiences of Dream Coaching
Authors: Wadensten Barbro
Published: December 2009

Background: Recalling and talking about dreams could initiate dream work among older people and provide an opportunity for self-confrontation and personal growth, which could in turn promote gerotranscendental development. The present article describes older people’s opinions about participating in a dream-coaching group; it also briefly describes the theoretical foundation of dream coaching. Aims and Objectives: The study aim was to investigate older people’s experience of participating in a dream-coaching group based on Jungian psychology. Design: A descriptive design was used. Method: Retrospective interviews were explored using qualitative content analysis. Findings: The participants were satisfied with the arrangement of the dream-coaching groups. All participants believed that they had recalled their dreams and thought much more about their dreams during the period in which the dream-coaching group met. Three diverse appraisals of participating in a dream-coaching group, which had different effects on the participants, were identified: “An activity like any other activity,” “An activity that led to deeper thoughts about the meaning of dreams,” and “An activity that led to deeper thoughts both about the meaning of dreams and about how dreams can improve one’s understanding of the life situation.” Conclusions: It is possible to arrange dream-coaching groups for older people and could be a way to promote personal development using this type of intervention. Implications: The study provides some guidance as to how such a group could be organized, thus facilitating use of dream-coaching groups in gerontological care.
Computerized Games and Simulations in Computer-Assisted Language Learning: A Meta-Analysis of Research
Authors: Peterson Mark
Published: December 2009

This article explores research on the use of computerized games and simulations in language education. The author examined the psycholinguistic and sociocultural constructs proposed as a basis for the use of games and simulations in computer-assisted language learning. Research in this area is expanding rapidly. However, to date, few studies have critically investigated this body of work. The author reviewed key findings from influential studies. The author’s analysis reveals that, although these studies are subject to limitations, simulations and games present valuable opportunities for effective language learning. The contemporary literature on theories of language acquisition hypothesizes that simulations and games are beneficial methods for helping learners acquire another language. This article concludes by identifying potential areas for future research.
Informal Reading Inventories
Authors: Provost Mary C. , Lambert Monica A. , Babkie Andrea M.
Published: December 2009

Mandates emphasizing student achievement have increased the importance of appropriate assessment techniques for students in general and special education classrooms. Informal reading inventories (IRIs), designed by classroom teachers, have been proven to be an efficient and effective way to determine students’ strengths, weaknesses, and strategies in the areas of reading fluency, decoding, sight-word recognition, and reading comprehension. Although there are commercially designed IRIs on the market, teachers may often have neither the access nor the funds to purchase them. Additionally, teacher-designed tests provide curriculum-based assessment, thus allowing a direct link between evaluation and instruction. This article gives general and special education teachers working in K—8 classrooms information on why IRIs are important, reasons for creating such inventories specifically for their classrooms, as well as step-by-step instructions on how to create IRIs using quality literature.
Preclinical Acute Toxicology Study of Surfactant-Stabilized Ultrasound Contrast Agents in Adult Rats
Authors: Forsberg Flemming , Liu Ji-Bin , Patel Mihir , Liu Liping , Lin Ling , Solis Carl , Fox Traci B. , Wheatley Margaret A.
Published: December 2009

Gas-filled microbubbles are used as contrast agents in diagnostic ultrasound imaging. A preclinical, acute toxicity study of 2 surfactant-stabilized ultrasound contrast agents (ST68 and ST44) was conducted. Subjects were 104 Sprague-Dawley rats (experimental doses, 0.1, 0.2, 0.8, and 1.0 mL/kg; control, 1.0 mL/kg saline) that were studied for 14 days after contrast; clinical signs, weight, blood, and urine were evaluated. Histopathology was performed following euthanasia. Of the 40 animals receiving ST44, 4 died prematurely and a dose dependency was demonstrated ( P = .011), whereas in the ST68 groups only 1 death occurred (no dose dependency; P = .48). Only the weight of rats injected with ST44 varied significantly ( P = .0003). This dependency was also found for 3 of 5 urine parameters and 4 of 36 blood parameters ( P < .05). For ST68, only 1 urine parameter showed significance ( P < .0001). Giant cell infiltration in the lungs was significantly higher than controls in the ST44 0.1 mL/kg and the ST68 0.8-1.0 mL/kg groups ( P < .01). It is concluded that the prudent choice for future nonrodent, toxicology studies and potentially for human clinical trials is ST68 (given the deaths in the ST44 groups).
An Examination of Technical Efficiency, Quality, and Patient Safety in Acute Care Nursing Units
Authors: Mark Barbara A. , Jones Cheryl Bland , Lindley Lisa , Ozcan Yasar A.
Published: December 2009

Using an innovative statistical approach—data envelopment analysis—the authors examined the technical efficiency of 226 medical, surgical, and medical—surgical nursing units in 118 randomly selected acute care hospitals. The authors used the inputs of registered nurse, licensed practical nurse, and unlicensed hours of care; operating expenses; and number of beds on the unit. Outputs included case mix adjusted discharges, patient satisfaction (as a quality measure), and the rates of medication errors and patient falls (as measures of patient safety). This study found that 60% of units were operating at less than full efficiency. Key areas for improvement included slight reductions in labor hours and large reductions in medication errors and falls. The study findings indicate the importance of improving patient safety as a mechanism to simultaneously improve nursing unit efficiency.
Erythropoietin accelerates smooth muscle cell–rich vascular lesion formation in mice through endothelial cell activation involving enhanced PDGF-BB release
Authors: Janmaat Maarten L. , Heerkens Jasper L. T. , de Bruin Alexander M. , Klous Anita , de Waard Vivian , de Vries Carlie J. M.
Published: December 2009

In this study, the effect of human erythropoietin Δ (Epo) on smooth muscle cell (SMC)–rich lesions was evaluated. Mice, of which the left carotid artery was ligated, were treated with suberythropoietic as well as erythropoietic doses of Epo and both doses of Epo enhanced SMC-rich lesion formation. No association was observed between hemoglobin levels and lesion size. Moreover, endothelial progenitor cell (EPC) numbers in the peripheral blood increased only in the erythropoietic dosing group, indicating that EPC numbers did not correlate with lesion size. Immunohistochemical analysis revealed that Epo-mediated enhancement of lesion formation correlates with increased signal transducer and activator of transcription 5 (Stat5) phosphorylation in the vessel wall. Experiments performed in cultured vascular cells demonstrated that Epo robustly induced phosphorylation of Stat5 in human umbilical vein endothelial cells (HUVECs), but only very weakly in SMCs. In tumor necrosis factor-α (TNFα)–activated HUVECS, Epo induced expression of platelet-derived growth factor B (PDGF-B), which was at least partially responsible for the induction of Stat5 phosphorylation in SMCs by HUVEC-conditioned medium. In conclusion, in mice Epo accelerates SMC-rich neointima formation, which correlates with increased Stat5 phosphorylation in the vessel wall but is independent of erythrocyte and EPC numbers.
Stem cell exhaustion due to Runx1 deficiency is prevented by Evi5 activation in leukemogenesis
Authors: Jacob Bindya , Osato Motomi , Yamashita Namiko , Wang Chelsia Qiuxia , Taniuchi Ichiro , Littman Dan R. , Asou Norio , Ito Yoshiaki
Published: December 2009

The RUNX1/AML1 gene is the most frequently mutated gene in human leukemia. Conditional deletion of Runx1 in adult mice results in an increase of hematopoietic stem cells (HSCs), which serve as target cells for leukemia; however, Runx1−/− mice do not develop spontaneous leukemia. Here we show that maintenance of Runx1−/− HSCs is compromised, progressively resulting in HSC exhaustion. In leukemia development, the stem cell exhaustion was rescued by additional genetic changes. Retroviral insertional mutagenesis revealed Evi5 activation as a cooperating genetic alteration and EVI5 overexpression indeed prevented Runx1−/− HSC exhaustion in mice. Moreover, EVI5 was frequently overexpressed in human RUNX1-related leukemias. These results provide insights into the mechanism for maintenance of pre-leukemic stem cells and may provide a novel direction for therapeutic applications.
HIV-1 Vpr up-regulates expression of ligands for the activating NKG2D receptor and promotes NK cell–mediated killing
Authors: Richard Jonathan , Sindhu Sardar , Pham Tram N. Q. , Belzile Jean-Philippe , Cohen Éric A.
Published: December 2009

HIV up-regulates cell-surface expression of specific ligands for the activating NKG2D receptor, including ULBP-1, -2, and -3, but not MICA or MICB, in infected cells both in vitro and in vivo. However, the viral factor(s) involved in NKG2D ligand expression still remains undefined. HIV-1 Vpr activates the DNA damage/stress-sensing ATR kinase and promotes G2 cell-cycle arrest, conditions known to up-regulate NKG2D ligands. We report here that HIV-1 selectively induces cell-surface expression of ULBP-2 in primary CD4+ T lymphocytes by a process that is Vpr dependent. Importantly, Vpr enhanced the susceptibility of HIV-1–infected cells to NK cell–mediated killing. Strikingly, Vpr alone was sufficient to up-regulate expression of all NKG2D ligands and thus promoted efficient NKG2D-dependent NK cell–mediated killing. Delivery of virion-associated Vpr via defective HIV-1 particles induced analogous biologic effects in noninfected target cells, suggesting that Vpr may act similarly beyond infected cells. All these activities relied on Vpr ability to activate the ATR-mediated DNA damage/stress checkpoint. Overall, these results indicate that Vpr is a key determinant responsible for HIV-1–induced up-regulation of NKG2D ligands and further suggest an immunomodulatory role for Vpr that may not only contribute to HIV-1–induced CD4+ T-lymphocyte depletion but may also take part in HIV-1–induced NK-cell dysfunction.
Plasminogen activator inhibitor-1 (PAI-1) is cardioprotective in mice by maintaining microvascular integrity and cardiac architecture
Authors: Xu Zhi , Castellino Francis J. , Ploplis Victoria A.
Published: December 2009

Although the involvement of plasminogen activator inhibitor-1 (PAI-1) in fibrotic diseases is well documented, its role in cardiac fibrosis remains controversial. The goal of this study was to determine the effect of a PAI-1 deficiency (PAI-1−/−) on the spontaneous development of cardiac fibrosis. PAI-1−/− mice developed pervasive cardiac fibrosis spontaneously with aging, and these mice displayed progressively distorted cardiac architecture and markedly reduced cardiac function. To mechanistically elucidate the role of PAI-1 in cardiac fibrosis, 12-week-old mice were chosen to study the biologic events leading to fibrosis. Although fibrosis was not observed at this early age, PAI-1−/− hearts presented with enhanced inflammation, along with increased microvascular permeability and hemorrhage. A potent fibrogenic cytokine, transforming growth factor-β (TGF-β), was markedly enhanced in PAI-1−/− heart tissue. Furthermore, the expression levels of several relevant proteases associated with tissue remodeling were significantly enhanced in PAI-1−/− hearts. These results suggest that PAI-1 is cardioprotective, and functions in maintaining normal microvasculature integrity. Microvascular leakage in PAI-1−/− hearts may provoke inflammation, and predispose these mice to cardiac fibrosis. Therefore, a PAI-1 deficiency contributes to the development of cardiac fibrosis by increasing vascular permeability, exacerbating local inflammation, and increasing extracellular matrix remodeling, an environment conducive to accelerated fibrosis.
Biochemical evidence for the tyrosine involvement in cationic intermediate stabilization in mouse β-carotene 15, 15'-monooxygenase
Authors: Poliakov Eugenia , Gentleman Susan , Chander Preethi , Cunningham Francis X , Grigorenko Bella L , Nemuhin Alexander V , Redmond T Michael
Published: December 2009

Background

β-carotene 15,15'-monooxygenase (BCMO1) catalyzes the crucial first step in vitamin A biosynthesis in animals. We wished to explore the possibility that a carbocation intermediate is formed during the cleavage reaction of BCMO1, as is seen for many isoprenoid biosynthesis enzymes, and to determine which residues in the substrate binding cleft are necessary for catalytic and substrate binding activity. To test this hypothesis, we replaced substrate cleft aromatic and acidic residues by site-directed mutagenesis. Enzymatic activity was measured in vitro using His-tag purified proteins and in vivo in a β-carotene-accumulating E. coli system.

Results

Our assays show that mutation of either Y235 or Y326 to leucine (no cation-π stabilization) significantly impairs the catalytic activity of the enzyme. Moreover, mutation of Y326 to glutamine (predicted to destabilize a putative carbocation) almost eliminates activity (9.3% of wt activity). However, replacement of these same tyrosines with phenylalanine or tryptophan does not significantly impair activity, indicating that aromaticity at these residues is crucial. Mutations of two other aromatic residues in the binding cleft of BCMO1, F51 and W454, to either another aromatic residue or to leucine do not influence the catalytic activity of the enzyme. Our ab initio model of BCMO1 with β-carotene mounted supports a mechanism involving cation-π stabilization by Y235 and Y326.

Conclusions

Our data are consistent with the formation of a substrate carbocation intermediate and cation-π stabilization of this intermediate by two aromatic residues in the substrate-binding cleft of BCMO1.
Multiple recombinants in two dengue virus, serotype-2 isolates from patients from Oaxaca, Mexico
Authors: Perez-Ramirez Gerardo , Diaz-Badillo Alvaro , Camacho-Nuez Minerva , Cisneros Alejandro , Munoz Maria de Lourdes
Published: December 2009

Background

Dengue (DEN) is a serious cause of mortality and morbidity in the world including Mexico, where the infection is endemic. One of the states with the highest rate of dengue cases is Oaxaca. The cause of DEN is a positive-sense RNA virus, the dengue virus (DENV) that evolves rapidly increasing its variability due to the absence of a repair mechanism that leads to approximately one mutational event per genome replication; which results in enhancement of viral adaptation, including the escape from host immune responses. Additionally, recombination may play a role in driving the evolution of DENV, which may potentially affect virulence and cause host tropism changes. Recombination in DENV has not been described in Mexican strains, neither has been described the relevance in virus evolution in an endemic state such as Oaxaca where the four serotypes of DENV are circulating.

Results

To study whether there are isolates from Oaxaca having recombination, we obtained the sequence of 6 different isolates of DENV-2 Asian/American genotype from the outbreak 2005-6, one clone of the C(91)-prM-E-NS1(2400) structural genes, and 10 clones of the E gene from the isolate MEX_OAX_1656_05. Evidence of recombination was found by using different methods along with two softwares: RDP3 and GARD. The Oaxaca MEX_OAX_1656_05 and MEX_OAX_1038_05 isolates sequenced in this study were recombinant viruses that incorporate the genome sequence from the Cosmopolitan genotype. Furthermore, the clone of the E gene namely MEX_OAX_165607_05 from this study was also recombinant, incorporating genome sequence from the American genotype.

Conclusions

This is the first report of recombination in DENV-2 in Mexico. Given such a recombinant activity new genomic combinations were produced, this could play a significant role in the DENV evolution and must be considered as a potentially important mechanism generating genetic variation in this virus with serious implications for the vaccines and drugs formulation as occurs for other viruses like poliovirus, influenza and HIV.
Phlegmonous colitis: another source of sepsis in cirrhotic patients?
Authors: Holzer Thomas , Gervaz Pascal , Spahr Laurent , McKee Thomas , Bucher Pascal , Morel Philippe
Published: December 2009

Background

The clinical relevance of phlegmonous colitis (PC), a rare autopsy finding in cirrhotic patients, is poorly documented. We postulated that PC might be a source of sepsis in patients with portal hypertensive colopathy (PHC).

Case presentation

We report three cirrhotic patients who were admitted with abdominal sepsis and who illustrate, to various degrees, the clinico-pathological sequence of colonic alterations associated with portal hypertension. Two cirrhotic patients with PHC developed gram-negative bacteraemia and quickly responded to intravenous antibiotics. Another cirrhotic patient underwent emergency colectomy for PC, and subsequently died from multiple organ failure. Histological alterations in the operative specimen included: a) mucosal ulcerations; b) disseminated micro-abscesses in the submucosa; and c) a severe vasculopathy leading to complete obliteration of submucosal blood vessels.

Conclusions

These data suggest that cirrhotic patients with PHC may progress towards PC, which, in turn, may be the cause for life-threatening sepsis.
Sensitive HPV detection in oropharyngeal cancers
Authors: Winder David M , Ball Siolian LR , Vaughan Katie , Hanna Nashat , Woo Yin Ling , Fränzer Jürgen-Theodor , Sterling Jane C , Stanley Margaret A , Sudhoff Holger , Goon Peter KC
Published: December 2009

Background

Human papillomaviruses (HPV) are the aetiological agents of certain benign and malignant tumours of skin and mucosae; the most important of which is cervical cancer. Also, the incidence of ano-genital warts, HPV-anal cancer and oropharyngeal cancers are rising. To help ascertain a useful PCR detection protocol for oropharyngeal cancers, we directly compared three commonly used primer sets in detection of HPV from different clinical samples.

Methods

We compared PGMY09/11, MY09/11 and GP5+/6+ primers sets in PCRs of 34 clinically diagnosed samples of genital warts, cervical brushings (with associated histological diagnosis) and vulval biopsies. All negative samples were subsequently tested using the previously reported PGMY/GP PCR method and amplicons directly sequenced for confirmation and typing. An optimised PCR protocol was then compared to a line blot assay for detection of HPV in 15 oropharyngeal cancer samples.

Results

PGMY09/11 primers detected HPV presence in more cervical brushing (100%) and genital wart (92.9%) samples compared to MY09/11 (90% and 64.3%) and GP5+/6+ (80% and 64.3%) primer sets, respectively. From vulval biopsies, HPV detection rates were: MY09/11 (63.6%), GP5+/6+ (54.5%) and PGMY09/11 (54.5%). PGMY/GP nested PCR demonstrated that HPV was present, and direct sequencing confirmed genotypes. This nested PCR protocol showed detection of HPV in 10/15 (66.7%) of oropharyngeal cancer samples.

Conclusions

PGMY09/11 primers are the preferred primer set among these three for primary PCR screening with different clinical samples. MY09/11 and GP5+/6+ may be used (particularly for cervical samples) but demonstrate lower detection rates. A nested PCR approach (i.e. a PGMY-GP system) may be required to confirm negativity or to detect low levels of HPV, undetectable using current primary PCR methods, as demonstrated using oropharyngeal cancer samples.
Design of the Balance@Work project: systematic development, evaluation and implementation of an occupational health guideline aimed at the prevention of weight gain among employees
Authors: Verweij Lisanne M , Proper Karin I , Weel Andre NH , Hulshof Carel TJ , van Mechelen Willem
Published: December 2009

Background

Occupational health professionals may play an important role in preventive health promotion activities for employees. However, due to a lack of knowledge and evidence- and practice based methods and strategies, interventions are hardly being implemented by occupational physicians to date. The aim of the Balance@Work project is to develop, evaluate, and implement an occupational health guideline aimed at the prevention of weight gain among employees.

Methods

Following the guideline development protocol of the Netherlands Society of Occupational Medicine and the Intervention Mapping protocol, the guideline was developed based on literature, interviews with relevant stakeholders, and consensus among an expert group. The guideline consists of an individual and an environmental component. The individual component includes recommendations for occupational physicians on how to promote physical activity and healthy dietary behavior based on principles of motivational interviewing. The environmental component contains an obesogenic environment assessment tool. The guideline is evaluated in a randomised controlled trial among 20 occupational physicians. Occupational physicians in the intervention group apply the guideline to eligible workers during 6 months. Occupational physicians in the control group provide care as usual. Measurements take place at baseline and 6, 12, and 18 months thereafter. Primary outcome measures include waist circumference, daily physical activity and dietary behavior. Secondary outcome measures include sedentary behavior, determinants of behavior change, body weight and body mass index, cardiovascular disease risk profile, and quality of life. Additionally, productivity, absenteeism, and cost-effectiveness are assessed.

Discussion

Improving workers' daily physical activity and dietary behavior may prevent weight gain and subsequently improve workers' health, increase productivity, and reduce absenteeism. After an effect- and process evaluation the guideline will be adjusted and, after authorisation, published. Together with several implementation aids, the published guideline will be disseminated broadly by the Netherlands Society of Occupational Medicine.

Trial Registration

ISRCTN73545254/NTR1190
Recombinant protein expression by targeting pre-selected chromosomal loci
Authors: Nehlsen Kristina , Schucht Roland , da Gama-Norton Leonor , Krömer Wolfgang , Baer Alexandra , Cayli Aziz , Hauser Hansjörg , Wirth Dagmar
Published: December 2009

Background

Recombinant protein expression in mammalian cells is mostly achieved by stable integration of transgenes into the chromosomal DNA of established cell lines. The chromosomal surroundings have strong influences on the expression of transgenes. The exploitation of defined loci by targeting expression constructs with different regulatory elements is an approach to design high level expression systems. Further, this allows to evaluate the impact of chromosomal surroundings on distinct vector constructs.

Results

We explored antibody expression upon targeting diverse expression constructs into previously tagged loci in CHO-K1 and HEK293 cells that exhibit high reporter gene expression. These loci were selected by random transfer of reporter cassettes and subsequent screening. Both, retroviral infection and plasmid transfection with eGFP or antibody expression cassettes were employed for tagging. The tagged cell clones were screened for expression and single copy integration. Cell clones producing > 20 pg/cell in 24 hours could be identified. Selected integration sites that had been flanked with heterologous recombinase target sites (FRTs) were targeted by Flp recombinase mediated cassette exchange (RMCE). The results give proof of principle for consistent protein expression upon RMCE. Upon targeting antibody expression cassettes 90-100% of all resulting cell clones showed correct integration. Antibody production was found to be highly consistent within the individual cell clones as expected from their isogenic nature. However, the nature and orientation of expression control elements revealed to be critical. The impact of different promoters was examined with the tag-and-targeting approach. For each of the chosen promoters high expression sites were identified. However, each site supported the chosen promoters to a different extent, indicating that the strength of a particular promoter is dominantly defined by its chromosomal context.

Conclusion

RMCE provides a powerful method to specifically design vectors for optimized gene expression with high accuracy. Upon considering the specific requirements of chromosomal sites this method provides a unique tool to exploit such sites for predictable expression of biotechnologically relevant proteins such as antibodies.
Developing 21stcentury accreditation standards for teaching hospitals: the Taiwan experience
Authors: Huang Chung-I , Wung Cathy , Yang Che-Ming
Published: December 2009

Background

The purpose of this study is to establish teaching hospital accreditation standards anew with the hope that Taiwan's teaching hospitals can live up to the expectations of our society and ensure quality teaching.

Methods

The development process lasted two years, 2005-2006, and was separated into three stages. The first stage centered on leadership meetings and consensus building, the second on drafting the new standards with expert focus groups, and the third on a pilot study and subsequent revision.

Results

Our new teaching hospital accreditation standards have six categories and 95 standards as follows: educational resources (20 items), teaching and training plans and outcomes (42 items), research and results (9 items), development of clinical faculty and continuing education (8 items), academic exchanges and community education (8 items), and administration (8 items).

Conclusions

The new standards have proven feasible and posed reasonable challenges in the pilot study. We hope the new standards will strengthen teaching and research, and improve the quality of hospital services at the same time.
An evolved xylose transporter from Zymomonas mobilis enhances sugar transport in Escherichia coli
Authors: Ren Chuan , Chen Tingjian , Zhang Jingqing , Liang Ling , Lin Zhanglin
Published: December 2009

Background

Xylose is a second most abundant sugar component of lignocellulose besides glucose. Efficient fermentation of xylose is important for the economics of biomass-based biorefineries. However, sugar mixtures are sequentially consumed in xylose co-fermentation with glucose due to carbon catabolite repression (CCR) in microorganisms. As xylose transmembrance transport is one of the steps repressed by CCR, it is therefore of interest to develop a transporter that is less sensitive to the glucose inhibition or CCR.

Results

The glucose facilitator protein Glf transporter from Zymomonas mobilis, also an efficient transporter for xylose, was chosen as the target transporter for engineering to eliminate glucose inhibition on xylose uptake. The evolution of Glf transporter was carried out with a mixture of glucose and xylose in E. coli. Error-prone PCR and random deletion were employed respectively in two rounds of evolution. Aided by a high-throughput screening assay using xylose analog p-nitrophenyl-β-D-xylopyranoside (pNPX) in 96-well plates, a best mutant 2-RD5 was obtained that contains several mutations, and a deletion of 134 residues (about 28% of total residues), or three fewer transmembrane sections (TMSs). It showed a 10.8-fold improvement in terms of pNPX transport activity in the presence of glucose. The fermentation performance results showed that this mutant improved xylose consumption by 42% with M9 minimal medium containing 20 g L-1 xylose only, while with the mixture sugar of xylose and glucose, 28% more glucose was consumed, but no obvious co-utilization of xylose was observed. Further glucose fed-batch experiments suggested that the intracellular metabolism of xylose was repressed by glucose.

Conclusions

Through random mutagenesis and partial deletion coupled with high-throughput screening, a mutant of the Glf transporter (2-RD5) was obtained that relieved the inhibition of xylose transport by glucose. The fermentation tests revealed that 2-RD5 was advantageous in xylose and glucose uptakes, while no obvious advantage was seen for xylose co-consumption when co-fermented with glucose. Further efforts could focus on reducing CCR-mediated repression of intracellular metabolism of xylose. Glf should also serve as a useful model to further exploit the molecular mechanism of xylose transport and the CCR-mediated inhibition.
2-Deoxy-D-glucose enhances TRAIL-induced apoptosis in human melanoma cells through XBP-1-mediated up-regulation of TRAIL-R2
Authors: Liu Hao , Jiang Chen Chen , Lavis Christopher J , Croft Amanda , Dong Li , Tseng Hsin-Yi , Yang Fan , Tay Kwang Hong , Hersey Peter , Zhang Xu Dong
Published: December 2009

Background

Past studies have shown that sensitivity of melanoma cells to TRAIL-induced apoptosis is largely correlated with the expression levels of TRAIL death receptors on the cell surface. However, fresh melanoma isolates and melanoma tissue sections express generally low levels of death receptors for TRAIL. The clinical potential of TRAIL in the treatment of melanoma may therefore be limited unless given with agents that increase the cell surface expression of TRAIL death receptors. 2-Deoxy-D-glucose (2-DG) is a synthetic glucose analogue that inhibits glycolysis and glycosylation and blocks cell growth. It has been in clinical evaluation for its potential use as an anticancer agent. In this study, we have examined whether 2-DG and TRAIL interact to enhance their cytotoxicity towards melanoma cells.

Results

2-DG did not kill melanoma cells, but enhanced TRAIL-induced apoptosis in cultured melanoma cells and fresh melanoma isolates. This was associated with increased activation of the caspase cascade and mitochondrial apoptotic pathway, and was blocked by inhibition of TRAIL-R2, and to a lesser extent, inhibition of TRAIL-R1. Treatment with 2-DG up-regulated TRAIL death receptors, in particular, TRAIL-R2, on the melanoma cell surface. Up-regulation of TRAIL-R2 was due to increased transcription that was not dependent on the transcription factors, p53 and CHOP. Instead, the IRE1α and ATF6 pathways of the unfolded protein response that were activated by 2-DG appeared to be involved. Moreover, XBP-1, which is known to be transcriptionally regulated by ATF6 and functionally activated by IRE1α, was found to play an important role in 2-DG-mediated transcriptional up-regulation of TRAIL-R2 in melanoma cells.

Conclusion

These results indicate that 2-DG sensitizes human melanoma cells to TRAIL-induced apoptosis by up-regulation of TRAIL-2 via the ATF6/IRE1α/XBP-1 axis of the unfolded protein response. They suggest that 2-DG is a promising agent to increase the therapeutic response to TRAIL in melanoma.
Adolescents' wellbeing and functioning: relationships with parents' subjective general physical and mental health
Authors: Giannakopoulos George , Dimitrakaki Christine , Pedeli Xanthi , Kolaitis Gerasimos , Rotsika Vasiliki , Ravens-Sieberer Ulricke , Tountas Yannis
Published: December 2009

Background

This study aimed at examining the relationship between parental subjective health status and adolescents' health-related quality of life (HRQoL) as well as the role of gender, socioeconomic status, presence of chronic health care needs and social support on the above interaction.

Methods

Questionnaires were administered to a Greek nation-wide random sample of adolescents (N = 1 194) aged 11-18 years and their parents (N = 973) in 2003. Adolescents' and parents' status was assessed, together with reports of socio-economic status and level of social support. Various statistical tests were used to determine the extent to which these variables were related to each other.

Results and Discussion

Parental subjective mental health status was significantly correlated with adolescents' better physical and psychological wellbeing, moods and emotions, parent-child relationships, school environment and financial resources. Parental subjective physical health status was strongly associated with more positive adolescents' self-perception. Adolescents' male gender, younger age, absence of chronic health care needs, high social support, and higher family income were positively associated with better HRQoL.

Conclusions

This study reinforces the importance of parental subjective health status, along with other variables, as a significant factor for the adolescents' HRQoL.
Isolated recurrence of distal adenocarcinoma of the extrahepatic bile duct on a draining sinus scar after curative resection: Case Report and review of the literature
Authors: Rodríguez-Pascual Jesús , De Vicente Emilio , Quijano Yolanda , Pérez-Rodríguez Francisco , Bergaz Fernando , Hidalgo Manuel , Duran Ignacio
Published: December 2009

Background

Surgical resection remains the gold standard for the treatment of localized adenocarcinoma of the extrahepatic bile ducts. Yet, treatment of loco-regional recurrences is not well defined.

Case Presentation

We present an unusual case of distal adenocarcinoma of the extrahepatic bile ducts that was treated with surgery and relapsed two years later with a solitary recurrence on the tract of a previous Redon drain. In addition, a review of the literature on management of loco regional relapses is presented.

Conclusions

The ideal management of these patients still remains undefined. Decisions are made based on clinical parameters from retrospective series, such as tumor grade, surgical margins or lymph node involvement. Prospective studies, that include molecular and genetic markers, are needed to improve patient selection and outcomes on this population.
DNA double strand break repair enzymes function at multiple steps in retroviral infection
Authors: Sakurai Yasuteru , Komatsu Kenshi , Agematsu Kazunaga , Matsuoka Masao
Published: December 2009

Background

DNA double strand break (DSB) repair enzymes are thought to be necessary for retroviral infection, especially for the post-integration repair and circularization of viral cDNA. However, the detailed roles of DSB repair enzymes in retroviral infection remain to be elucidated.

Results

A GFP reporter assay showed that the infectivity of an HIV-based vector decreased in ATM- and DNA-PKcs-deficient cells when compared with their complemented cells, while that of an MLV-based vector was diminished in Mre11- and DNA-PKcs-deficient cells. By using a method based on inverse- and Alu-PCR, we analyzed sequences around 3' HIV-1 integration sites in ATM-, Mre11- and NBS1- deficient cells. Increased abnormal junctions between the HIV-1 provirus and the host DNA were found in these mutant cell lines compared to the complemented cell lines and control MRC5SV cells. The abnormal junctions contained two types of insertions: 1) GT dinucleotides, which are normally removed by integrase during integration, and 2) inserted nucleotides of unknown origin. Artemis-deficient cells also showed such abnormalities. In Mre11-deficient cells, part of a primer binding site sequence was also detected. The 5' host-virus junctions in the mutant cells also contained these types of abnormal nucleotides. Moreover, the host-virus junctions of the MLV provirus showed similar abnormalities. These findings suggest that DSB repair enzymes play roles in the 3'-processing reaction and protection of the ends of viral DNA after reverse transcription. We also identified both 5' and 3' junctional sequences of the same provirus by inverse PCR and found that only the 3' junctions were abnormal with aberrant short repeats, indicating that the integration step was partially impaired in these cells. Furthermore, the conserved base preferences around HIV-1 integration sites were partially altered in ATM-deficient cells.

Conclusions

These results suggest that DSB repair enzymes are involved in multiple steps including integration and pre-integration steps during retroviral replication.
Longitudinal trends in the association of metabolic syndrome with 550 k single-nucleotide polymorphisms in the Framingham Heart Study
Authors: Park Yong-Moon , Province Michael A , Gao Xiaoyi , Feitosa Mary , Wu Jun , Ma Duanduan , Rao DC , Kraja Aldi T
Published: December 2009

We investigated the association of metabolic syndrome (MetS) with a 500 k and a 50 k single-nucleotide polymorphism (SNP) gene chip in the Framingham Heart Study. We cross-sectionally evaluated the MetS longitudinal trends. Data analyzed were from the Offspring Cohort (four exams: first (n = 2,441), third (n = 2,185), fifth (n = 2,308), and seventh (n = 2,328)) and the Generation 3 Cohort (one exam: the first exam (n = 3,997)). The prevalence of MetS was determined using the National Cholesterol Education Program Adult Treatment Panel III diagnostic criteria, modified with a newly developed correction for medication use. The association test between an SNP and MetS was performed with a generalized estimating equations method under the additive genetic model. Multiple-testing corrections were also performed. The prevalence of MetS in the offspring cohort increased from one visit to the next, and reached the highest point by the seventh exam comparable with the prevalence reported for the general US population. The pattern of the MetS prevalence over time also reflected itself in the association tests, in which the highest significances were seen in the fifth and seventh exams. The association tests showed that SNPs within genes PRDM16, CETP, PTHB1, PAPPA, and FBN3, and also some SNPs not in genes were significant or close to significance at the genome-wide thresholds. These findings are important in terms of eventually identifying with the causal loci for MetS.
Genome-wide association analysis of cardiovascular-related quantitative traits in the Framingham Heart Study
Authors: Roslin Nicole M , Hamid Jemila S , Paterson Andrew D , Beyene Joseph
Published: December 2009

Multivariate linear growth curves were used to model high-density lipoprotein (HDL), low-density lipoprotein (LDL), triglycerides (TG), and systolic blood pressure (SBP) measured during four exams from 1659 independent individuals from the Framingham Heart Study. The slopes and intercepts from each of two phenotype models were tested for association with 348,053 autosomal single-nucleotide polymorphisms from the Affymetrix Gene Chip 500 k set. Three regions were associated with LDL intercept, TG slope, and SBP intercept (p < 1.44 × 10-7). We observed results consistent with previously reported associations between rs599839, on chromosome 1p13, and LDL. We note that the association is significant with LDL intercept but not slope. Markers on chromosome 17q25 were associated with TG slope, and a single-nucleotide polymorphism on chromosome 7p11 was associated with SBP intercept. Growth curve models can be used to gain more insight on the relationships between SNPs and traits than traditional association analysis when longitudinal data has been collected. The power to detect association with changes over time may be limited if the subjects are not followed over a long enough time period.
A comparative study of three methods for detecting association of quantitative traits in samples of related subjects
Authors: Saint Pierre Aude , Vitezica Zulma , Martinez Maria
Published: December 2009

We used Genetic Analysis Workshop 16 Problem 3 Framingham Heart Study simulated data set to compare methods for association analysis of quantitative traits in related individuals. More specifically, we investigated type I error and relative power of three approaches: the measured genotype, the quantitative transmission-disequilibrium test (QTDT), and the quantitative trait linkage-disequilibrium (QTLD) tests. We studied high-density lipoprotein and triglyceride (TG) lipid variables, as measured at Visit 1. Knowing the answers, we selected three true major genes for high-density lipoprotein and/or TG. Empirical distributions of the three association models were derived from the first 100 replicates. In these data, all three models were similar in error rates. Across the three association models, the power was the lowest for the functional SNP with smallest size effects (i.e., α2), and for the less heritable trait (i.e., TG). Our results showed that measured genotype outperformed the two orthogonal-based association models (QTLD, QTDT), even after accounting for population stratification. QTDT had the lowest power rates. This is consistent with the amount of marker and trait data used by each association model. While the effective sample sizes varied little across our tested variants, we observed some large power drops and marked differences in performances of the models. We found that the performances contrasted the most for the tightly linked, but not associated, functional variants.
Region-based analysis in genome-wide association study of Framingham Heart Study blood lipid phenotypes
Authors: Asimit Jennifer L , Yoo Yun Joo , Waggott Daryl , Sun Lei , Bull Shelley B
Published: December 2009

Due to the high-dimensionality of single-nucleotide polymorphism (SNP) data, region-based methods are an attractive approach to the identification of genetic variation associated with a certain phenotype. A common approach to defining regions is to identify the most significant SNPs from a single-SNP association analysis, and then use a gene database to obtain a list of genes proximal to the identified SNPs. Alternatively, regions may be defined statistically, via a scan statistic. After categorizing SNPs as significant or not (based on the single-SNP association p-values), a scan statistic is useful to identify regions that contain more significant SNPs than expected by chance. Important features of this method are that regions are defined statistically, so that there is no dependence on a gene database, and both gene and inter-gene regions can be detected. In the analysis of blood-lipid phenotypes from the Framingham Heart Study (FHS), we compared statistically defined regions with those formed from the top single SNP tests. Although we missed a number of single SNPs, we also identified many additional regions not found as SNP-database regions and avoided issues related to region definition. In addition, analyses of candidate genes for high-density lipoprotein, low-density lipoprotein, and triglyceride levels suggested that associations detected with region-based statistics are also found using the scan statistic approach.