bluuebunny/crossref_metadata_2025 huggingface dataset:
Chinese Health Beliefs of Older Chinese in Canada
Authors: Lai Daniel W. L. , Surood Shireen
Published: January 2009

Objectives: This study examines the cultural health beliefs held by older Chinese in Canada. Methods: Chinese surnames are randomly selected from the local Chinese telephone directories. Telephone screening is then conducted to identify eligible Chinese people 55 years of age or older to take part in a face-to-face interview to complete a structured survey questionnaire. Results: The results of exploratory factor analysis indicate that the health beliefs of the older Chinese are loaded onto three factors related to beliefs about traditional health practices, beliefs about traditional Chinese medicine, and beliefs about preventive diet. Education, religion, country of origin, length of residency in Canada, and city of residency are the major correlates of the various Chinese health beliefs scales. Discussion: The findings support the previous prescriptive knowledge about Chinese health beliefs and illustrate the intragroup sociocultural diversity that health practitioners should acknowledge in their practice.
Factors Affecting Frontline Workers' Satisfaction With Supervision
Authors: Noelker Linda S. , Ejaz Farida K. , Menne Heather L. , Bagaka's Joshua G.
Published: January 2009

Objective: This research was guided by a stress and support model to examine the effects of frontline workers' background characteristics, personal stressors, job-related stressors, and workplace support on satisfaction with supervision. Method: Survey data were collected from 644 workers in 49 long-term—care settings that employed them. Regression analysis were used to determine the effects of worker level and then Hierarchical Linear Modeling (HLM) and organizational factors on the outcome. Results: Although all four variable categories made significant contributions to explaining satisfaction with supervision, the most powerful were personal stressors and job-related stressors. Results from HLM analysis showed frontline workers in nursing homes and those employed in for-profit organizations had lower levels of satisfaction with supervision. Discussion: Findings suggest organizational interventions to address workers' financial and health issues and management practices such as better training programs and peer mentoring could enhance workers' satisfaction with supervision.
A Decade of Internationalisation
Authors: Montgomery Catherine
Published: January 2009

This article considers how student views of collaborative study in a diverse international academic context may have changed in the past decade. A retrospective is provided on a research project carried out in 1998 that investigated students' views of working in international groups; this is linked with research carried out by the author in 2008. Despite the fact that examples of ethnic reductionism remain, there appeared to be a more positive social atmosphere in the 2008 data; students perceived cross-cultural interaction as valuable. Where there were conflicts within groups, these stemmed from clashes over disciplinary variation and differences in ideas about how to get things done. This article provides some suggestions for why there was a more positive working atmosphere between students.
Evolutionary Changes in Service Attribute Importance in a Crisis Scenario The Uruguayan Financial Crisis
Authors: Kim Moshe , Lado Nora , Torres Anna
Published: January 2009

This article attempts to identify and assess the evolution of consumers' differential reactions to major service attribute classes that resulted from and were propagated by a severe financial crisis. The authors perform a longitudinal analysis, using correspondence analysis of square asymmetric matrices, on data generated from three different postcrisis time periods. The first period encompasses data during the 2 weeks after the crisis occurred, the second period assesses data 1 year later, and the third period refers to 5 years later. The results from the first and second periods both indicate the growing importance of credence attributes rather than search attributes compared with during the precrisis period. The third-period analysis indicates a reversal and greater importance of the search attributes that were important in the precrisis period. The results also reveal correlations with the type of banking organization. These findings point to important managerial implications; bank management's inability to realize the shift in consumers' attitudes failed to facilitate and expedite a resolution to the crisis.
Peripheral arterial disease and cognitive function
Authors: Rafnsson Snorri B , Deary Ian J , Fowkes FGR
Published: January 2009

Abstract

As a marker of generalized atherosclerosis, peripheral arterial disease (PAD) has implications not only for the affected lower extremity but also to overall cardiovascular health. It confers an increased risk of non-fatal and fatal vascular events which increases with the severity of the disease. Patient-based studies have shown that individuals with advanced PAD tend to perform poorly on cognitive tests compared to controls. In population studies, PAD is associated with an increased cognitive decline independently of previous cerebrovascular disease and cardiovascular risk factors. A low ankle–brachial index (ABI) may be an early predictor of cognitive decline and of potential value in identifying individuals at increased risk of cognitive impairment. In patients with PAD, secondary preventive measures directed at decreasing the long-term systemic vascular complications may also be important to the preservation of cognitive health. However, evidence suggests that PAD patients may be undertreated with regard to atherosclerotic risk factors, as demonstrated by an undue emphasis on symptom relief rather than essential risk factor reduction. More research needs to be carried out to determine the predictors of cognitive function in PAD patients, whether subtle cognitive disturbances are related to activities of daily living, including medical treatment compliance, and whether neuroprotective strategies and atherosclerotic risk factor control positively influence cognitive function in these high-risk patients.
Gender in medicine — does it matter?
Authors: Hølge-Hazelton Bibi , Malterud Kirsti
Published: January 2009

Aims: A broad range of socio-cultural issues have been recognized as determinants for health and disease. A notion of gender neutrality is still alive in the medical culture, suggesting that gender issues are not relevant within this field. Methods: We have explored the claim that doctors encounter their patients as human beings, not as men or women, and discuss causes and consequences of such a claim. Results: Empirical evidence does not support such a claim — gender seems to have a strong impact on medical knowledge and practice. The concept andronormativity signifies a state of affairs where male values are regarded as normal to the extent that female values disappear or need to be blatantly highlighted in order to be recognized. We have applied this frame of reference to understand how the idea of gender neutrality has been established in medicine. The average medical practitioner, teacher, or researcher is a man. We suggest that notions of normality subtly construct gender in medicine in ways where men become normal, while women become deviant. Finally, we discuss strengths and pitfalls of three different strategies which have been used by gender researchers in health to challenge andronormativity: demonstrating gender differences, revealing the consequences of gendered power inequalities, and deconstructing the meaning of gender. Conclusions: We conclude that gender still matters in medicine.
Do childhood social circumstances affect overweight and obesity in early adulthood?
Authors: Kestilä Laura , Rahkonen Ossi , Martelin Tuija , Lahti-Koski Marjaana , Koskinen Seppo
Published: January 2009

Aims: The aim of the study was to examine the association of childhood circumstances with overweight and obesity in early adulthood, to analyse whether the respondent's education and current circumstances mediate these associations, and to explore whether the respondent's health behaviour affects these associations. Design: This was a cross-sectional study with retrospective inquiries. Methods: The study was based on a representative two-stage cluster sample (N= 1894, participation rate 79%) of young adults aged 18—29 years in Finland in 2000. The outcome measure was three-class body mass index (BMI) (normal weight, overweight, and obesity). Multinomial logistic regression was used as the main statistical tool. Results: In women, childhood circumstances (low parental education (relative risk ratio (RRR) = 2.43), parental unemployment (RRR= 2.09) and single-parent family (RRR= 1.99)) increased the risk of overweight (25 ≤ BMI<30), but the effects were largely attenuated by other childhood factors and early adult circumstances. In men, no significant childhood predictors of overweight were found. Single-parent family (RRR=2.32), parental alcohol problem (RRR= 2.71), parental mental health problems (RRR=2.28) and being bullied at school (RRR=3.13) predicted obesity (BMI ≥ 30) in women in the age-adjusted models, and being bullied at school remained a significant predictor after adjusting for all childhood and current determinants. In both genders, the strong association between parental education and obesity remained significant after adjusting for all other determinants (for the lowest educational category, RRR= 3.56 in women, and RRR= 6.55 in men). Conclusions: Childhood factors predict overweight and obesity in early adulthood. This effect is stronger on obesity than on overweight and in women than in men, and it seems to be partly mediated by adult circumstances. The results emphasize the lasting effect of childhood socioeconomic position on adult obesity. When preventive policies are being planned, social circumstances in childhood should be addressed.
Short- and long-term adverse effects of cocaine abuse during pregnancy on the heart development
Authors: Meyer Kurt D. , Zhang Lubo
Published: January 2009

The effect of cocaine on the developing fetus is a topic of considerable interest and debate. One of the potential effects of fetal cocaine exposure is damage to the developing heart. This review provides an overview of the current understanding of the short- and long-term effects of fetal cocaine exposure on the heart in both humans and animal models. Human studies are still preliminary but have suggested that fetal cocaine exposure impacts on the developing heart. Studies in animal models provide strong evidence for a programming effect resulting in detrimental long-term changes to the heart induced by fetal cocaine exposure. In the rat model, fetal cocaine results in apoptosis in the term heart, left ventricular remodeling and myocyte hypertrophy, as well as increased sensitivity to ischemia/reperfusion injury in the adult male offspring. The rat model has also shown evidence of epigenetic modifications in response to intrauterine cocaine. Increased DNA methylation of promoter regions leads to a long-term decrease in the expression of the cardioprotective gene, PKCε. The current data shows fetal cocaine exposure has significant immediate and long-term cardiac consequences in animal models and while human studies are still incomplete they suggest this phenomenon may also be significant in humans exposed to cocaine during development.
Correction of murine ADAMTS13 deficiency by hematopoietic progenitor cell–mediated gene therapy
Authors: Laje Pablo , Shang Dezhi , Cao Wenjing , Niiya Masami , Endo Masayuki , Radu Antoneta , DeRogatis Nicole , Scheiflinger Friedrich , Zoltick Philip W. , Flake Alan W. , Zheng X. Long
Published: January 2009

ADAMTS13, a metalloprotease primarily synthesized in liver and endothelial cells, cleaves von Willebrand factor (VWF) at the central A2 domain, thereby reducing the sizes of circulating VWF multimers. Genetic or acquired deficiency of plasma ADAMTS13 activity leads to a potentially fatal syndrome, thrombotic thrombocytopenic purpura (TTP). To date, plasma infusion or exchange is the only proven effective therapy for TTP. In search for a better therapy, an autologous transplantation of hematopoietic progenitor cells transduced ex vivo with a self-inactivating lentiviral vector encoding a full-length murine Adamts13 and an enhanced green fluorescent protein (GFP) reporter gene was performed in Adamts13−/− mice after irradiation. All recipient mice showed detectable ADAMTS13 antigen and proteolytic activity in plasma despite only low levels of bone marrow chimerism. The levels of plasma ADAMTS13 were sufficient to eliminate the ultralarge VWF multimers and offered systemic protection against ferric chloride–induced arterial thrombosis. The data suggest that hematopoietic progenitor cells can be genetically modified ex vivo and transplanted in an autologous model to provide adequate levels of functional ADAMTS13 metalloprotease. This success may provide the basis for development of a novel therapeutic strategy to cure hereditary TTP in humans.
Structures of the spectrin-ankyrin interaction binding domains
Authors: Ipsaro Jonathan J. , Huang Lei , Mondragón Alfonso
Published: January 2009

As key components of the erythrocyte membrane skeleton, spectrin and ankyrin specifically interact to tether the spectrin cytoskeleton to the cell membrane. The structure of the spectrin binding domain of ankyrin and the ankyrin binding domain of spectrin have been solved to elucidate the structural basis for ankyrin-spectrin recognition. The structure of repeats 14 and 15 of spectrin shows that these repeats are similar to all other spectrin repeats. One feature that could account for the preference of ankyrin for these repeats is the presence of a conserved, negatively charged patch on one side of repeat 14. The structure of the ankyrin ZU5 domain shows a novel structure containing a β core. The structure reveals that the canonical ZU5 consensus sequence is likely to be missing an important region that codes for a β strand that forms part of the core of the domain. In addition, a positively charged region is suggestive of a binding surface for the negatively charged spectrin repeat 14. Previously reported mutants of ankyrin that map to this region lie mostly on the surface of the protein, although at least one is likely to be part of the core.
Suppression of CXCL12 production by bone marrow osteoblasts is a common and critical pathway for cytokine-induced mobilization
Authors: Christopher Matthew J. , Liu Fulu , Hilton Matthew J. , Long Fanxin , Link Daniel C.
Published: January 2009

Current evidence suggests that hematopoietic stem/progenitor cell (HSPC) mobilization by granulocyte colony-stimulating factor (G-CSF) is mediated by induction of bone marrow proteases, attenuation of adhesion molecule function, and disruption of CXCL12/CXCR4 signaling in the bone marrow. The relative importance and extent to which these pathways overlap or function independently are uncertain. Despite evidence of protease activation in the bone marrow, HSPC mobilization by G-CSF or the chemokine Groβ was abrogated in CXCR4−/− bone marrow chimeras. In contrast, HSPC mobilization by a VLA-4 antagonist was intact. To determine whether other mobilizing cytokines disrupt CXCR4 signaling, we characterized CXCR4 and CXCL12 expression after HSPC mobilization with Flt3 ligand (Flt3L) and stem cell factor (SCF). Indeed, treatment with Flt3L or SCF resulted in a marked decrease in CXCL12 expression in the bone marrow and a loss of surface expression of CXCR4 on HSPCs. RNA in situ and sorting experiments suggested that the decreased CXCL12 expression is secondary to a loss of osteoblast lineage cells. Collectively, these data suggest that disruption of CXCR4 signaling and attenuation of VLA-4 function are independent mechanisms of mobilization by G-CSF. Loss of CXCL12 expression by osteoblast appears to be a common and key step in cytokine-induced mobilization.
Improved risk classification for risk-specific therapy based on the molecular study of minimal residual disease (MRD) in adult acute lymphoblastic leukemia (ALL)
Authors: Bassan Renato , Spinelli Orietta , Oldani Elena , Intermesoli Tamara , Tosi Manuela , Peruta Barbara , Rossi Giuseppe , Borlenghi Erika , Pogliani Enrico M. , Terruzzi Elisabetta , Fabris Pietro , Cassibba Vincenzo , Lambertenghi-Deliliers Giorgio , Cortelezzi Agostino , Bosi Alberto , Gianfaldoni Giacomo , Ciceri Fabio , Bernardi Massimo , Gallamini Andrea , Mattei Daniele , Di Bona Eros , Romani Claudio , Scattolin Anna Maria , Barbui Tiziano , Rambaldi Alessandro
Published: January 2009

Clinical risk classification is inaccurate in predicting relapse in adult patients with acute lymphoblastic leukemia, sometimes resulting in patients receiving inappropriate chemotherapy or stem cell transplantation (SCT). We studied minimal residual disease (MRD) as a predictive factor for recurrence and as a decisional tool for postconsolidation maintenance (in MRDneg) or SCT (in MRDpos). MRD was tested at weeks 10, 16, and 22 using real-time quantitative polymerase chain reaction with 1 or more sensitive probes. Only patients with t(9;22) or t(4;11) were immediately eligible for allogeneic SCT. Of 280 registered patients (236 in remission), 34 underwent an early SCT, 60 suffered from relapse or severe toxicity, and 142 were evaluable for MRD at the end of consolidation. Of these, 58 were MRDneg, 54 MRDpos, and 30 were not assessable. Five-year overall survival/disease-free survival rates were 0.75/0.72 in the MRDneg group compared with 0.33/0.14 in MRDpos (P = .001), regardless of the clinical risk class. MRD was the most significant risk factor for relapse (hazard ratio, 5.22). MRD results at weeks 16 to 22 correlated strongly with the earlier time point (P = .001) using a level of 10−4 or higher to define persistent disease. MRD analysis during early postremission therapy improves risk definitions and bolsters risk-oriented strategies. ClinicalTrials.gov identifier: NCT00358072.
Social and environmental malaria risk factors in urban areas of Ouagadougou, Burkina Faso
Authors: Baragatti Meili , Fournet Florence , Henry Marie-Claire , Assi Serge , Ouedraogo Herman , Rogier Christophe , Salem Gérard
Published: January 2009

Background

Despite low endemicity, malaria remains a major health problem in urban areas where a high proportion of fevers are presumptively treated using anti-malarial drugs. Low acquired malaria immunity, behaviour of city-dwellers, access to health care and preventive interventions, and heterogenic suitability of urban ecosystems for malaria transmission contribute to the complexity of the malaria epidemiology in urban areas.

Methods

The study was designed to identify the determinants of malaria transmission estimated by the prevalence of anti-circumsporozoite (CSP) antibodies, the prevalence and density of Plasmodium falciparum infection, and the prevalence of malarial disease in areas of Ouagadougou, Burkina-Faso. Thick blood smears, dried blood spots and clinical status have been collected from 3,354 randomly chosen children aged 6 months to 12 years using two cross-sectional surveys (during the dry and rainy seasons) in eight areas from four ecological strata defined according to building density and land tenure (regular versus irregular). Demographic characteristics, socio-economic information, and sanitary and environmental data concerning the children or their households were simultaneously collected. Dependent variables were analysed using mixed multivariable models with random effects, taking into account the clustering of participants within compounds and areas.

Results

Overall prevalences of CSP-antibodies and P. falciparum infections were 7.7% and 16.6% during the dry season, and 12.4% and 26.1% during the rainy season, respectively, with significant differences according to ecological strata. Malaria risk was significantly higher among children who i) lived in households with lower economic or education levels, iii) near the hydrographic network, iv) in sparsely built-up areas, v) in irregularly built areas, vi) who did not use a bed net, vii) were sampled during the rainy season or ii) had traveled outside of Ouagadougou.

Conclusion

Malaria control should be focused in areas which are irregularly or sparsely built-up or near the hydrographic network. Furthermore, urban children would benefit from preventive interventions (e.g. anti-vectorial devices or chemoprophylaxis) aimed at reducing malaria risk during and after travel in rural areas.
Stem cells from umbilical cord blood do have myogenic potential, with and without differentiation induction in vitro
Authors: Jazedje Tatiana , Secco Mariane , Vieira Natássia M , Zucconi Eder , Gollop Thomaz R , Vainzof Mariz , Zatz Mayana
Published: January 2009

The dystrophin gene, located at Xp21, codifies dystrophin, which is part of a protein complex responsible for the membrane stability of muscle cells. Its absence on muscle causes Duchenne Muscular Dystrophy (DMD), a severe disorder, while a defect of muscle dystrophin causes Becker Muscular Dystrophy (DMB), a milder disease. The replacement of the defective muscle through stem cells transplantation is a possible future treatment for these patients. Our objective was to analyze the potential of CD34+ stem cells from umbilical cord blood to differentiate in muscle cells and express dystrophin, in vitro. Protein expression was analyzed by Immunofluorescence, Western Blotting (WB) and Reverse Transcriptase – Polymerase Chain Reaction (RT-PCR). CD34+ stem cells and myoblasts from a DMD affected patient started to fuse with muscle cells immediately after co-cultures establishment. Differentiation in mature myotubes was observed after 15 days and dystrophin-positive regions were detected through Immunofluorescence analysis. However, WB or RT-PCR analysis did not detect the presence of normal dystrophin in co-cultures of CD34+ and DMD or DMB affected patients' muscle cells. In contrast, some CD34+ stem cells differentiated in dystrophin producers' muscle cells, what was observed by WB, reinforcing that this progenitor cell has the potential to originate muscle dystrophin in vitro, and not just in vivo like reported before.
Smoking Behaviors Among Cancer Survivors: An Observational Clinical Study
Authors: Burke Lola , Miller Lesley-Ann , Saad Ayman , Abraham Jame
Published: January 2009

Purpose:

Smoking is a well-recognized risk factor for several cancers including cancers of the lung, bladder, and head and neck. Studies have shown that smoking can adversely affect the outcomes of different modalities of cancer treatment. This study examines smoking behaviors among cancer survivors to collect information necessary to create successful smoking cessation interventions.

Methods:

For this observational clinical study, questionnaires were sent to 1,000 randomly selected patients diagnosed with cancer between 2003 and 2007 in one cancer center. Data were statistically analyzed to determine the likelihood of a patient quitting smoking after being diagnosed with cancer.

Results:

We received 187 responses from the 1,000 surveys sent (18.7%). Of these, 166 were usable for analysis. The mean age of respondents was 64 (± 13) years. Men were more likely than women to be past smokers (55% of men and 32% of women respectively, P = .003). Fifty-two percent of respondents reported having a history of smoking. However, only 20% of patients reported having been active smokers at the time they were diagnosed with cancer. Furthermore, only 44% of these reported having quit smoking after their diagnosis with cancer. Only 62% of all respondents reported that they had been informed of the dangers of smoking by their health care provider during cancer treatment.

Conclusion:

In our study sample, less than one half (44%) of smoking cancer patients quit smoking after their cancer diagnosis, and only 62% of smoking cancer patients received smoking cessation counseling from their physicians. Intervention programs are needed to help cancer survivors to quit smoking. Prospective clinical trials may help identify the ideal intervention for smoking cessation.
Prediction of Changes in Bone Mineral Density in Postmenopausal Women Treated with Once-Weekly Bisphosphonates
Authors: Burnett-Bowie Sherri-Ann M. , Saag Kenneth , Sebba Anthony , de Papp Anne E. , Chen Erluo , Rosenberg Elizabeth , Greenspan Susan L.
Published: January 2009

Background: In clinical practice, bone mineral density (BMD) determined by dual-energy x-ray absorptiometry is used to monitor response to osteoporosis therapy. However, 1 to 2 yr are usually required to assess patients’ BMD responses. The possibility of earlier indicators of a response or nonresponse to treatment, such as changes in bone turnover markers (BTMs), is of interest to physicians and patients.

Methods: In this post hoc analysis of women treated with once-weekly bisphosphonates, we examined the association of tertile percentage change from baseline in BTMs at 3 or 6 months and association of several baseline clinical characteristics with 24-month percentage change from baseline in BMD and with percentage of patients showing BMD nonresponse (defined as BMD loss at two or more of four sites) at 24 months. Multivariable analysis was performed to determine which factors were independently associated with BMD nonresponse.

Results: Patients in the tertile with the greatest decrease in each of the BTMs had the greatest mean increase in BMD and the lowest percentage of BMD nonresponders at 24 months. Several characteristics were independently associated with BMD nonresponse, including smaller 3-month reductions from baseline in serum C-terminal telopeptide of type 1 collagen, bone-specific alkaline phosphatase, and N-terminal propeptide of type 1 procollagen; younger age of menopause; a family history of osteoporosis; and higher baseline trochanteric BMD. Baseline BTMs were not predictive of 24-month BMD response to therapy. The strongest associations were for changes in BTMs with treatment.

Conclusion: In groups of patients, short-term changes in markers of bone turnover appear to be predictors of longer term BMD response and nonresponse to bisphosphonate therapy.
Competition between wear and rolling contact fatigue at the wheel—rail interface: some experimental evidence on rail steel
Authors: Donzella G , Mazzù A , Petrogalli C
Published: January 2009

Recent studies of the rail—wheel interface have shown that wear and rolling contact fatigue (RCF) are competitive phenomena. Wear, by removing the material from the contact surface, tends to limit the propagation of cracks formed by cyclic contact stresses. Several parameters influence these phenomena. This article studies the effects of various working conditions on the surface damage of railway steels. The competition between wear and RCF is particularly strong in dry rolling—sliding contacts, in which the damage severity of our test cases can be adequately predicted using the shakedown map. In wet contacts, RCF is prevalent: cracks rapidly propagate into the subsurface layer in response to hydraulic pressure penetration and then branch towards the surface causing severe damage (macroscopic pitting). The severity of this phenomenon depends strongly on the applied load and cannot be inhibited by wear due to the low friction. On the basis of these results, a general procedure is proposed to the structural integrity of rails.
Preparation of Propanethiol-Modified Nanoporous Silica Spherical Particles
Authors: Ogawa Makoto , Kato Kei , Shimura Naoki
Published: January 2009

Spherical particles of nanoporous silica (with a diameter of 600 nm) containing mercaptopropylsilyl groups on the pore surface were synthesized by a modified Stöber method and subsequently silylated using (3-mercaptopropyl)trimethoxysilane. The spherical particles of organosilica formed an artificial opal structure by simply casting the suspension (water dimethylformamide mixture) on a mercaptopropylsilylated Si wafer.
Experimental and Computational Studies on the Dipole Moments of Annulated-Tropones and 1,4-Polyacenequinones
Authors: Kudoh Mitsutaka , Satoh Takehiko , Ikeda Hiroshi , Nakazawa Tomoo , Miyashi Tsutomu , Katagiri Shigeyoshi , Sudoh Susumu
Published: January 2009

From both the experimental and computational perspectives, we examined the annulation effects of benzene rings on the ground-state dipole moment for two series of conjugated ketones. The first is a series of tropones (1), 4,5-benzotropone (2), 4,5-naphthotropone (3), 4,5-anthratropone (4), 4,5-tetracenotropone (5), and 4,5-pentacenotropone (6). The second is a series of 1,4-benzoquinones (7), 1,4-naphthoquinone (8), 1,4-anthraquinone (9), 1,4-tetracenequinone (10), 1,4-pentacenequinone (11), 1,4-hexacenequinone (12), and 5,12-tetracenequinone (13). Among these compounds, we determined the ground-state dipole moments of compounds 3, 9, 10, and 13 experimentally as 5.19, 2.07, 2.95, and 1.33 D, respectively. The ground-state dipole moments of the above two series were calculated by Hartree–Fock (HF), density functional theory (DFT), and Møller–Plesset second-order perturbation (MP2) methods. We examined the ground-state dipole moments of the two series to determine whether they converge to a limit. From the MP2 calculations, we estimated the converged dipole moments of annulated-tropones and 1,4-polyacenequinone, as 7.58 and 6.17 D, respectively.
Photoinduced Hydrogen Production with a Platinum Nanoparticle and Light-Harvesting Chlorophyll a/b–Protein Complex of Photosystem II (LHCII) from Spinach System
Authors: Ishigure Shuichi , Okuda Ayumi , Fujii Kaoru , Maki Yuko , Nango Mamoru , Amao Yutaka
Published: January 2009

Photoinduced hydrogen production via the photoreduction of methyl viologen (MV2+) using the sensitization of light-harvesting chlorophyll a/b–protein complex of photosystem II (LHCII) from spinach in the presence of platinum nanoparticles and NADH is developed.
Direct In Vitro Selection of Hemin-Binding DNA Aptamer with Peroxidase Activity
Authors: Liu Mingzhe , Kagahara Takuma , Abe Hiroshi , Ito Yoshihiro
Published: January 2009

A novel hemin-binding DNA was synthesized using in vitro selection (SELEX) method. The selected DNA not only bound to the hemin, but also had peroxidase activity when complexed with hemin. A pool of 104-nt single-stranded DNA (ssDNA) molecules containing a randomized sequence of 60 nt was synthesized. The DNA pool having random sequences was incubated with a hemin-immobilized affinity column. Bound DNAs were eluted with hemin solution and amplified by PCR with biotin-labeled primers. ssDNAs were isolated from the biotin-labeled double-stranded DNA (dsDNA) molecules after each selection process. After four rounds of selection process, the selected DNAs were cloned and sequenced. Four DNA aptamers were chemically synthesized from the sequenced clones. Two aptamers exhibited binding affinity to hemin and peroxidase activity. A 21-nt oligonucleotide was designed from the aptamer sequence that formed a complex with hemin and exhibited high peroxidase activity.
A bioinformatics search pipeline, RNA2DSearch, identifies RNA localization elements in Drosophila retrotransposons
Authors: Hamilton Russell S. , Hartswood Eve , Vendra Georgia , Jones Cheryl , Van De Bor Veronique , Finnegan David , Davis Ilan
Published: January 2009

mRNA localization is a widespread mode of delivering proteins to their site of function. The embryonic axes in Drosophila are determined in the oocyte, through Dynein-dependent transport of gurken/TGF-α mRNA, containing a small localization signal that assigns its destination. A signal with a similar secondary structure, but lacking significant sequence similarity, is present in the I factor retrotransposon mRNA, also transported by Dynein. It is currently unclear whether other mRNAs exist that are localized to the same site using similar signals. Moreover, searches for other genes containing similar elements have not been possible due to a lack of suitable bioinformatics methods for searches of secondary structure elements and the difficulty of experimentally testing all the possible candidates. We have developed a bioinformatics approach for searching across the genome for small RNA elements that are similar to the secondary structures of particular localization signals. We have uncovered 48 candidates, of which we were able to test 22 for their localization potential using injection assays for Dynein mediated RNA localization. We found that G2 and Jockey transposons each contain a gurken/I factor-like RNA stem–loop required for Dynein-dependent localization to the anterior and dorso–anterior corner of the oocyte. We conclude that I factor, G2, and Jockey are members of a “family” of transposable elements sharing a gurken-like mRNA localization signal and Dynein-dependent mechanism of transport. The bioinformatics pipeline we have developed will have broader utility in fields where small RNA signals play important roles.
Immunostaining of Plasma Cells in Primary Biliary Cirrhosis
Authors: Daniels Jason A. , Torbenson Michael , Anders Robert A. , Boitnott John K.
Published: January 2009

Primary biliary cirrhosis (PBC) is a chronic cholestatic liver disease characterized by inflammatory destruction of the intrahepatic bile ducts. The differential diagnosis for PBC often includes autoimmune hepatitis (AIH). Both diseases can show prominent plasma cells and other overlapping histologic features. It is interesting that both diseases can involve elevated levels of serum immunoglobulins, with IgM elevations typical of PBC and IgG elevations typical of AIH. We investigated whether this difference could be useful histologically by immunostaining plasma cells in liver biopsy specimens for IgG and IgM. We examined 56 cases: 18 of PBC and 38 of AIH. In PBC, plasma cells in the portal tracts were predominantly IgM+, whereas in AIH, plasma cells were predominately IgG+ (P < .0001). Immunostaining for IgM and IgG can be helpful in differentiating PBC from AIH.
Saturated Fatty Acids Produce an Inflammatory Response Predominantly through the Activation of TLR4 Signaling in Hypothalamus: Implications for the Pathogenesis of Obesity
Authors: Milanski Marciane , Degasperi Giovanna , Coope Andressa , Morari Joseane , Denis Raphael , Cintra Dennys E. , Tsukumo Daniela M. L. , Anhe Gabriel , Amaral Maria E. , Takahashi Hilton K. , Curi Rui , Oliveira Helena C. , Carvalheira José B. C. , Bordin Silvana , Saad Mário J. , Velloso Lício A.
Published: January 2009

In animal models of diet-induced obesity, the activation of an inflammatory response in the hypothalamus produces molecular and functional resistance to the anorexigenic hormones insulin and leptin. The primary events triggered by dietary fats that ultimately lead to hypothalamic cytokine expression and inflammatory signaling are unknown. Here, we test the hypothesis that dietary fats act through the activation of toll-like receptors 2/4 and endoplasmic reticulum stress to induce cytokine expression in the hypothalamus of rodents. According to our results, long-chain saturated fatty acids activate predominantly toll-like receptor 4 signaling, which determines not only the induction of local cytokine expression but also promotes endoplasmic reticulum stress. Rats fed on a monounsaturated fat-rich diet do not develop hypothalamic leptin resistance, whereas toll-like receptor 4 loss-of-function mutation and immunopharmacological inhibition of toll-like receptor 4 protects mice from diet-induced obesity. Thus, toll-like receptor 4 acts as a predominant molecular target for saturated fatty acids in the hypothalamus, triggering the intracellular signaling network that induces an inflammatory response, and determines the resistance to anorexigenic signals.
Head Direction Cell Instability in the Anterior Dorsal Thalamus after Lesions of the Interpeduncular Nucleus
Authors: Clark Benjamin J. , Sarma Asha , Taube Jeffrey S.
Published: January 2009

Previous research has identified a population of cells throughout the limbic system that discharge as a function of the animal's head direction (HD). Altering normal motor cues can alter the HD cell responses and disrupt the updating of their preferred firing directions, thus suggesting that motor cues contribute to processing the HD signal. A pathway that conveys motor information may stem from the interpeduncular nucleus (IPN), a brain region that has reciprocal connections with HD cell circuitry. To test this hypothesis, we produced electrolytic or neurotoxic lesions of the IPN and recorded HD cells in the anterior dorsal thalamus (ADN) of rats. Direction-specific firing remained present in the ADN after lesions of the IPN, but measures of HD cell properties showed that cells had reduced peak firing rates, large directional firing ranges, and firing that predicted the animal's future heading more than in intact controls. Furthermore, preferred firing directions were moderately less influenced by rotation of a salient visual landmark. Finally, the preferred directions of cells in lesioned rats exhibited large shifts when the animals foraged for scattered food pellets in a darkened environment and when locomoting from a familiar environment to a novel one. We propose that the IPN contributes motor information about the animal's movements to the HD cell circuitry. Furthermore, these results suggest that the IPN plays a broad role in the discharge properties and stability of direction-specific activity in the HD cell circuit.
Single Nigrostriatal Dopaminergic Neurons Form Widely Spread and Highly Dense Axonal Arborizations in the Neostriatum
Authors: Matsuda Wakoto , Furuta Takahiro , Nakamura Kouichi C. , Hioki Hiroyuki , Fujiyama Fumino , Arai Ryohachi , Kaneko Takeshi
Published: January 2009

The axonal arbors of single nigrostriatal dopaminergic neurons were visualized with a viral vector expressing membrane-targeted green fluorescent protein in rat brain. All eight reconstructed tyrosine hydroxylase-positive dopaminergic neurons possessed widely spread and highly dense axonal arborizations in the neostriatum. All of them emitted very little axon collateral arborization outside of the striatum except for tiny arborization in the external pallidum. The striatal axonal bush of each reconstructed dopaminergic neuron covered 0.45–5.7% (mean ± SD = 2.7 ± 1.5%) of the total volume of the neostriatum. Furthermore, all the dopaminergic neurons innervated both striosome and matrix compartments of the neostriatum, although each neuron's arborization tended to favor one of these compartments. Our findings demonstrate that individual dopaminergic neurons of the substantia nigra can broadcast a dopamine signal and exert strong influence over a large number of striatal neurons. This divergent signaling should be a key to the function of the nigrostriatal system in dopamine-based learning and suggests that neurodegeneration of individual nigral neurons can affect multiple neurons in the striatum. Thus, these results would also contribute to understanding the clinicopathology of Parkinson's disease and related syndromes.
Ribosomal S6 Kinase Cooperates with Casein Kinase 2 to Modulate theDrosophilaCircadian Molecular Oscillator
Authors: Akten Bikem , Tangredi Michelle M. , Jauch Eike , Roberts Mary A. , Ng Fanny , Raabe Thomas , Jackson F. Rob
Published: January 2009

There is a universal requirement for post-translational regulatory mechanisms in circadian clock systems. Previous work inDrosophilahas identified several kinases, phosphatases, and an E3 ligase that are critical for determining the nuclear translocation and/or stability of clock proteins. The present study evaluated the function of p90 ribosomal S6 kinase (RSK) in theDrosophilacircadian system. In mammals, RSK1 is a light- and clock-regulated kinase known to be activated by the mitogen-activated protein kinase pathway, but there is no direct evidence that it functions as a component of the circadian system. Here, we show thatDrosophilaS6KII RNA displays rhythms in abundance, indicative of circadian control. Importantly, anS6KIInull mutant exhibits a short-period circadian phenotype that can be rescued by expression of the wild-type gene in clock neurons, indicating a role for S6KII in the molecular oscillator. Peak PER clock protein expression is elevated in the mutant, indicative of enhanced stability, whereaspermRNA level is decreased, consistent with enhanced feedback repression. Gene reporter assays show that decreased S6KII is associated with increased PER repression. Surprisingly, we demonstrate a physical interaction between S6KII and the casein kinase 2 regulatory subunit (CK2β), suggesting a functional relationship between the two kinases. In support of such a relationship, there are genetic interactions betweenS6KIIandCK2mutations,in vivo, which indicate that CK2 activity is required for S6KII action. We propose that the two kinases cooperate within clock neurons to fine-tune circadian period, improving the precision of the clock mechanism.
Abnormal Network Activity in a Targeted Genetic Model of Human Double Cortex
Authors: Ackman James B. , Aniksztejn Laurent , Crépel Valérie , Becq Hélène , Pellegrino Christophe , Cardoso Carlos , Ben-Ari Yehezkel , Represa Alfonso
Published: January 2009

In human patients, cortical dysplasia produced byDoublecortin(DCX) mutations lead to mental retardation and intractable infantile epilepsies, but the underlying mechanisms are not known. DCX−/−mice have been generated to investigate this issue. However, they display no neocortical abnormality, lessening their impact on the field. In contrast,in uteroknockdown of DCX RNA produces a morphologically relevant cortical band heterotopia in rodents. On this preparation we have now compared the neuronal and network properties of ectopic, overlying, and control neurons in an effort to identify how ectopic neurons generate adverse patterns that will impact cortical activity. We combined dynamic calcium imaging and anatomical and electrophysiological techniques and report now that DCX−/−EGFP+-labeled ectopic neurons that fail to migrate develop extensive axonal subcortical projections and retain immature properties, and most of them display a delayed maturation of GABA-mediated signaling. Cortical neurons overlying the heterotopia, in contrast, exhibit a massive increase of ongoing glutamatergic synaptic currents reflecting a strong reactive plasticity. Neurons in both experimental fields are more frequently coactive in coherent synchronized oscillations than control cortical neurons. In addition, both fields displayed network-driven oscillations during evoked epileptiform burst. These results show that migration disorders produce major alterations not only in neurons that fail to migrate but also in their programmed target areas. We suggest that this duality play a major role in cortical dysfunction of DCX brains.
Differential Effect of Reward and Punishment on Procedural Learning
Authors: Wächter Tobias , Lungu Ovidiu V. , Liu Tao , Willingham Daniel T. , Ashe James
Published: January 2009

Reward and punishment are potent modulators of associative learning in instrumental and classical conditioning. However, the effect of reward and punishment on procedural learning is not known. The striatum is known to be an important locus of reward-related neural signals and part of the neural substrate of procedural learning. Here, using an implicit motor learning task, we show that reward leads to enhancement of learning in human subjects, whereas punishment is associated only with improvement in motor performance. Furthermore, these behavioral effects have distinct neural substrates with the learning effect of reward being mediated through the dorsal striatum and the performance effect of punishment through the insula. Our results suggest that reward and punishment engage separate motivational systems with distinctive behavioral effects and neural substrates.
Border Ownership Selectivity in Human Early Visual Cortex and its Modulation by Attention
Authors: Fang Fang , Boyaci Huseyin , Kersten Daniel
Published: January 2009

Natural images are usually cluttered because objects occlude one another. A critical aspect of recognizing these visual objects is to identify the borders between image regions that belong to different objects. However, the neural coding of border ownership in human visual cortex is largely unknown. In this study, we designed two simple but compelling stimuli in which a slight change of contextual information could induce a dramatic change of border ownership. Using functional MRI adaptation, we found that border ownership selectivity in V2 was robust and reliable across subjects, and it was largely dependent on attention. Our study provides the first human evidence that V2 is a critical area for the processing of border ownership and that this processing depends on the modulation from higher-level cortical areas.
benFunctions withScampduring Synaptic Transmission and Long-Term Memory Formation inDrosophila
Authors: Zhao Hong , Zheng Xingguo , Yuan Xiaojing , Wang Lei , Wang Xin , Zhong Yi , Xie Zuoping , Tully Tim
Published: January 2009

Genetic screens forDrosophilamutants defective in pavlovian olfactory memory have provided unique insight into the molecular basis of memory storage. Occasionally, these singular genetic lesions have been assembled into meaningful molecular pathways and neural circuitries. For the most part, however, these genes and their expression patterns in the CNS remain fragmented, demanding new clues from continued mutant screens. From a behavioral screen for long-term memory (LTM) mutants, we have identifiedben(CG32594), which encodes a novel protein. Mutations ofbenspecifically disrupt LTM, leaving earlier memory phases intact. The role ofbenappears physiological rather than developmental, because acutely induced expression of aben+transgene in adults rescues the mutant's LTM defect. More interestingly, induced expression ofben+specifically in mushroom bodies (MBs), but not in the ellipsoid body of the central complex, is sufficient to rescue the mutant LTM defect. This suggests a role forbenin the MB during olfactory memory formation. We also provide evidence that BEN interacts genetically in both synaptic transmission and LTM formation with SCAMP, a synaptic protein known to be involved in vesicle recycling.
Dopamine D4Receptors Regulate AMPA Receptor Trafficking and Glutamatergic Transmission in GABAergic Interneurons of Prefrontal Cortex
Authors: Yuen Eunice Y. , Yan Zhen
Published: January 2009

GABAergic interneurons in prefrontal cortex (PFC) play a critical role in cortical circuits by providing feedforward and feedback inhibition and synchronizing neuronal activity. Impairments in GABAergic inhibition to PFC pyramidal neurons have been implicated in the abnormal neural synchrony and working memory disturbances in schizophrenia. The dopamine D4receptor, which is strongly linked to neuropsychiatric disorders, such as attention deficit–hyperactivity disorder (ADHD) and schizophrenia, is highly expressed in PFC GABAergic interneurons, while the physiological role of D4in these interneurons is largely unknown. In this study, we found that D4activation caused a persistent suppression of AMPAR-mediated synaptic transmission in PFC interneurons. This effect of D4receptors on AMPAR-EPSC was via a mechanism dependent on actin/myosin V motor-based transport of AMPA receptors, which was regulated by cofilin, a major actin depolymerizing factor. Moreover, we demonstrated that the major cofilin-specific phosphatase Slingshot, which was activated by calcineurin downstream of D4signaling, was required for the D4regulation of glutamatergic transmission. Thus, D4receptors, by using the unique calcineurin/Slingshot/cofilin signaling mechanism, regulate actin dynamics and AMPAR trafficking in PFC GABAergic interneurons. It provides a potential mechanism for D4receptors to control the excitatory synaptic strength in local-circuit neurons and GABAergic inhibition in the PFC network, which may underlie the role of D4receptors in normal cognitive processes and mental disorders.