bluuebunny/crossref_metadata_2025 huggingface dataset:
Correlations Between White Matter Integrity and Motor Function in Traumatic Brain Injury Patients
Authors: Caeyenberghs Karen , Leemans Alexander , Geurts Monique , Linden Catharine Vander , Smits-Engelsman Bouwien C. M. , Sunaert Stefan , Swinnen Stephan P.
Published: March 2011

Background. Deterioration of motor function is one of several clinical manifestations following traumatic brain injury (TBI) in children and adolescents. Objective. To investigate the relationship between white matter (WM) integrity using diffusion tensor imaging (DTI) and motor functioning in young TBI patients. Methods. A group with moderate to severe TBI (n = 24) and a control group (n = 17) were scanned using DTI along with standard anatomical scans. Using ExploreDTI software, WM regions/tracts that carry efferent output (motor) from the brain were evaluated, as well as the corpus callosum, brainstem, internal capsule, and subcortical WM structures. Motor function was assessed using the Movement Assessment Battery for Children (M-ABC), consisting of manual dexterity, ball skills, and static and dynamic balance items. Results. TBI patients were less successful on the M-ABC than the controls and showed lower WM fractional anisotropy (FA) in the corpus callosum, anterior corona radiata, corticospinal tract, and cerebellum. Decreased FA was associated with lower motor performance in the TBI group but not in the control group. Conclusion. This study provides evidence for a structural alteration of motor pathways and regions in children and adolescents with TBI that are correlated with motor functioning. Further studies may be able to identify therapeutic targets and monitor the effects of new interventions.
Equivalent Retention of Gains at 1 Year After Training With Constraint-Induced or Bimanual Therapy in Children With Unilateral Cerebral Palsy
Authors: Sakzewski Leanne , Ziviani Jenny , Abbott David F. , Macdonell Richard A. L. , Jackson Graeme D. , Boyd Roslyn N.
Published: March 2011

Objectives. To determine retention of treatment outcomes at 52 weeks following a matched-pairs randomized comparison trial of constraint-induced movement therapy (CIMT) and bimanual training (BIM). Methods. Sixty-four children (mean age = 10.2 ± 2.7 years, 52% male) were included. The Melbourne Assessment of Unilateral Upper Limb Function (MUUL), Assisting Hand Assessment (AHA), and Canadian Occupational Performance Measure (COPM) were the primary outcome measures. Evaluations were at baseline and at 26 and 52 weeks. Results. There were no baseline differences between groups on any measure. No significant differences were found between groups on primary outcomes at 52 weeks. Both groups retained the significant gains made from baseline to 26 weeks at the 1-year follow-up assessment for unimanual capacity on the MUUL, for bimanual performance on the AHA, and on the COPM. Conclusion. Intensive unimanual and bimanual training can both lead to long-term significant improvements in unimanual capacity, bimanual performance, and individualized outcomes. Gains established at 26 weeks were maintained at 12 months postintervention despite most children receiving no direct therapy during that time.
Selling National Value at the Auction Market: The London and Dublin Markets for Irish Art
Authors: Herrero Marta
Published: March 2011

This article explores how nationality is articulated as a form of art value in the art market, where art is defined in two related ways: instrumentally, in terms of its economic value, and culturally, by defining its meaning and significance. Focusing on the auction market of Irish art in London and in Dublin, and drawing upon interviews with auctioneers in both capitals, it investigates how nationality is produced and marketed as a form of cultural value for Irish art, comparing the specific dynamics of this process in both London and Dublin auction markets. Whilst the findings in this article agree with existing literature on the economic and cultural forms of art value prevalent in art markets, they add to the literature by arguing that the cultural, national element of value-making for Irish art is very pronounced.
The Economic Sociologies of Pierre Bourdieu
Authors: Swedberg Richard
Published: March 2011

Instead of trying to locate the economic sociology of Bourdieu, I argue that his analysis of the economy was developed over such a long time period, is so rich and goes in so many interesting directions, that we are justified in speaking of Bourdieu’s economic sociologies in the plural. While most sociologists know about Bourdieu’s study Distinction (1986) and its analysis of consumption, there is less awareness of the fact that Bourdieu himself, towards the end of his life, said that he had produced three major studies of economic topics. These are: his work in Algeria on ‘the economy of honour and “good faith”’ (1950s and 1960s); his study of credit (Bourdieu et al., 1963); and his study of the economy of single-family houses (Bourdieu et al., 1999). These three studies are presented and discussed in detail, and so is Bourdieu’s attempt to formulate a general program for ‘economic anthropology’ in his article ‘The Economic Field’ (1997), drawing on such concepts as field, habitus and capital. Some critique has been directed at Bourdieu’s analysis of the economy, and this is also discussed.
Pierre Bourdieu as a Post-cultural Theorist
Authors: Lizardo Omar
Published: March 2011

Pierre Bourdieu is without doubt one of the main figures in the sociological study of culture today. Yet, for a theorist so central to the subject matter of cultural studies, it is clear that there is no coherent account of Bourdieu stance in relation to the ‘concept of culture’ among current commentators. More importantly, in the sister-discipline of anthropology, Bourdieu is thought of as a central figure precisely because he helped move contemporary anthropological theory away from the centrality of the culture concept. This paper reviews this peculiar double reception of Bourdieu’s anthropological and sociological work, closely examining these unacknowledged strands of Bourdieu’s thinking on culture. The basic argument is that the anthropological reception of Bourdieu’s work is more faithful to the outlines of his late-career intellectual development while the sociological portrayal — Bourdieu as a Sausserean culture theorist with a ‘Weberian power twist’— is fundamentally misleading. I close by outlining how Bourdieu’s work points towards a yet-to-be developed ‘post-cultural’ stance — one that takes cognition, experience and the body seriously — in the sociological study of culture.
Bourdieu, Historicity, and Historical Sociology
Authors: Steinmetz George
Published: March 2011

This article examines Bourdieu’s contributions to history and historical sociology. Bourdieu has often been misread as an ahistorical ‘reproduction theorist’ whose work does not allow for diachronic change or human agency. The article argues that both reproduction and social change, constraint and freedom, are at the heart of Bourdieu’s project. Bourdieu’s key concepts — habitus, field, cultural and symbolic capital — are all inherently historical. Bourdieu deploys his basic categories using a distinctly historicist social epistemology organized around the ideas of conjuncture, contingency, overdetermination, and radical discontinuity. The origins of Bourdieu’s historicism are traced to his teachers at the École Normale Supérieure and to the long-standing aspirations among French historians and sociologists to unify the two disciplines. The historical nature of Bourdieu’s work is also signalled by its pervasive influence on historians and the historical work of his former students and colleagues. Bourdieu allowed sociology to historicize itself to a greater extent than other French sociologists.
From Bourdieu to Cultural Sociology
Authors: Santoro Marco
Published: March 2011

This paper offers an account of Bourdieu’s rise to sociological ‘stardom’ in the last 30 years, giving special attention to the transnational dimensions of this process. It discusses the scope and relevance of his work to the field (in the making) of cultural sociology, showing how he contributed to its current form. It also presents the articles which constitute the contents of the journal special issue. The paper insists on the importance of assessing both the virtues and limits of Bourdieu’s intellectual legacy through the means of historicization and sociological self-understanding, these being preconditions that allow the furthering of the ‘progress of reason’ which Bourdieu himself located as at the core of scientific endeavours.
The Development of Primary Central Nervous System B-Cell Lymphoma in Multiple Sclerosis
Authors: Lyons Mark K. , Boucher Orland K. , Birch Barry D. , Patel Naresh P.
Published: March 2011

When coupled with classical clinical signs and symptoms, magnetic resonance imaging can significantly aid in the diagnosis of multiple sclerosis (MS). However, the differential diagnosis of multiple sclerosis is large and, in the absence of pathognomonic clinical features, can be challenging to diagnose initially. Some conditions, such as primary central nervous system lymphoma (PCNSL) and progressive multifocal leukoencephalopathy (PML), can mimic clinically some of the symptoms prominent in multiple sclerosis. Early treatment with corticosteroids can dramatically improve patient symptoms in MS and PCNSL. We report a case of a man diagnosed with histologically confirmed relapsing remitting multiple sclerosis who subsequently developed histologically confirmed primary central nervous system lymphoma. Immunosuppressant therapy in the treatment of multiple sclerosis may be a potential catalyst in the development of central nervous system lymphoma. The course of his disease and treatment are presented and the current literature reviewed.
Functional interactions between Lmo2, the Arf tumor suppressor, and Notch1 in murine T-cell malignancies
Authors: Treanor Louise M. , Volanakis Emmanuel J. , Zhou Sheng , Lu Taihe , Sherr Charles J. , Sorrentino Brian P.
Published: March 2011

LMO2 is a target of chromosomal translocations in T-cell tumors and was activated by retroviral vector insertions in T-cell tumors from X-SCID patients in gene therapy trials. To better understand the cooperating genetic events in LMO2-associated T-cell acute lymphoblastic leukemia (T-ALL), we investigated the roles of Arf tumor suppressor loss and Notch activation in murine models of transplantation. Lmo2 overexpression enhanced the expansion of primitive DN2 thymocytes, eventually facilitating the stochastic induction of clonal CD4+/CD8+ malignancies. Inactivation of the Arf tumor suppressor further increased the self-renewal capacity of the primitive, preleukemic thymocyte pool and accelerated the development of aggressive, Lmo2-induced T-cell lympholeukemias. Notch mutations were frequently detected in these Lmo2-induced tumors. The Arf promoter was not directly engaged by Lmo2 or mutant Notch, and use of a mouse model in which activation of a mutant Notch allele depends on previous engagement of the Arf promoter revealed that Notch activation could occur as a subsequent event in T-cell tumorigenesis. Therefore, Lmo2 cooperates with Arf loss to enhance self-renewal in primitive thymocytes. Notch mutation and Arf inactivation appear to independently cooperate in no requisite order with Lmo2 overexpression in inducing T-ALL, and all 3 events remained insufficient to guarantee immediate tumor development.
Genome-wide promoter DNA methylation dynamics of human hematopoietic progenitor cells during differentiation and aging
Authors: Bocker Michael T. , Hellwig Isabelle , Breiling Achim , Eckstein Volker , Ho Anthony D. , Lyko Frank
Published: March 2011

DNA methylation plays an important role in the self-renewal of hematopoietic stem cells and in the commitment to the lymphoid or myeloid lineages. Using purified CD34+ hematopoietic progenitor cells and differentiated myeloid cell populations from the same human samples, we obtained detailed methylation profiles at distinct stages of hematopoiesis. We identified a defined set of differentiation-related genes that are methylated in CD34+ hematopoietic progenitor cells but show pronounced DNA hypomethylation in monocytes and in granulocytes. In addition, by comparing hematopoietic progenitor cells from umbilical cord blood to hematopoietic progenitor cells from peripheral blood of adult donors we were also able to analyze age-related methylation changes in CD34+ cells. Interestingly, the methylation changes observed in older progenitor cells showed a bimodal pattern with hypomethylation of differentiation-associated genes and de novo methylation events resembling epigenetic mutations. Our results thus provide detailed insight into the methylation dynamics during differentiation and suggest that epigenetic changes contribute to hematopoietic progenitor cell aging.
Human CD8 T cells generated in vitro from hematopoietic stem cells are functionally mature
Authors: Awong Génève , Herer Elaine , La Motte-Mohs Ross N , Zúñiga-Pflücker Juan Carlos
Published: March 2011

Background

T cell development occurs within the highly specialized thymus. Cytotoxic CD8 T cells are critical in adaptive immunity by targeting virally infected or tumor cells. In this study, we addressed whether functional CD8 T cells can be generated fullyin vitrousing human umbilical cord blood (UCB) hematopoietic stem cells (HSCs) in coculture with OP9-DL1 cells.

Results

HSC/OP9-DL1 cocultures supported the differentiation of CD8 T cells, which were TCR/CD3hiCD27hiCD1anegand thus phenotypically resembled mature functional CD8 single positive thymocytes. Thesein vitro-generated T cells also appeared to be conventional CD8 cells, as they expressed high levels ofEomesand low levels ofPlzf, albeit not identical toex vivoUCB CD8 T cells. Consistent with the phenotypic and molecular characterization, upon TCR-stimulation,in vitro-generated CD8 T cells proliferated, expressed activation markers (MHC-II, CD25, CD38), secreted IFN-γ and expressed Granzyme B, a cytotoxic T-cell effector molecule.

Conclusion

Taken together, the ability to direct human hematopoietic stem cell or T-progenitor cells towards a mature functional phenotype raises the possibility of establishing cell-based treatments for T-immunodeficiencies by rapidly restoring CD8 effector function, thereby mitigating the risks associated with opportunistic infections.
A genetic variant in the APE1/Ref-1 gene promoter -141T/G may modulate risk of glioblastoma in a Chinese Han population
Authors: Zhou Keke , Hu Dezhi , Lu Juan , Fan Weiwei , Liu Hongliang , Chen Hongyan , Chen Gong , Wei Qingyi , Du Guhong , Mao Ying , Lu Daru , Zhou Liangfu
Published: March 2011

Background

The human apurinic/apyrimidinic endonuclease 1/Redox effector factor-1 (APE1/Ref-1) is implicated in tumor development and progression. Recently, the APE1/Ref-1 promoter -141T/G variant (rs1760944) has been reported to be associated with lung cancer risk. Given the importance of APE1/Ref-1 in both DNA repair and redox activity, we speculate that the -141T/G polymorphism may confer individual susceptibility to gliomas or its subtypes.

Methods

The APE1/Ref-1 -141T/G polymorphism was analyzed in a case-control study including 766 glioma patients (among them 241 glioblastoma, 284 astrocytomas except for glioblastoma and 241 other gliomas) and 824 cancer-free controls from eastern China. Genotyping was performed with Sequenom MassARRAY iPLEX platform by use of allele-specific MALDI-TOF mass spectrometry assay. We estimated odds ratios (ORs) and 95% confidence intervals (95% CIs) using unconditional logistic regression. A test of trend was calculated using the genotype as an ordinal variable in the regression model. For each statistically significant association identified, we estimated the false positive reporting probability (FPRP). FPRP values less than 0.2 were consider to indicate robust associations.

Results

The significant association between the APE1/Ref-1 promoter -141T/G polymorphism and glioma risk was not observed. However, the stratified analysis by histology revealed the variant allele G significantly decreased glioblastoma risk (OR = 0.80, 95% CI = 0.65-0.98, P = 0.032). Individuals with the homozygous -141GG genotype exhibited 46% reduced risk of glioblastoma (adjusted OR = 0.54, 95% CI 0.34-0.87, P = 0.012), compared with the TT homozygote. This result remained robust given the prior probabilities of 25% (FPRP = 0.052) and 10% (FPRP = 0.140), but not with a prior probability of 1% (FPRP = 0.643). The P-associated with the trend test was 0.014.

Conclusions

Our results suggest that a specific genetic variant located in the APE1/Ref-1 promoter may modulate risk of glioblastoma, but not for other histological gliomas. Larger studies with more APE1 polymorphisms are required to validate these preliminary findings.
Controlling pH in shake flasks using polymer-based controlled-release discs with pre-determined release kinetics
Authors: Scheidle Marco , Dittrich Barbara , Klinger Johannes , Ikeda Hideo , Klee Doris , Büchs Jochen
Published: March 2011

Background

There are significant differences in the culture conditions between small-scale screenings and large-scale fermentation processes. Production processes are usually conducted in fed-batch cultivation mode with active pH-monitoring and control. In contrast, screening experiments in shake flasks are usually conducted in batch mode without active pH-control, but with high buffer concentrations to prevent excessive pH-drifts. These differences make it difficult to compare results from screening experiments and laboratory and technical scale cultivations and, thus, complicate rational process development. In particular, the pH-value plays an important role in fermentation processes due to the narrow physiological or optimal pH-range of microorganisms. To reduce the differences between the scales and to establish a pH-control in shake flasks, a newly developed easy to use polymer-based controlled-release system is presented in this paper. This system consists of bio-compatible silicone discs embedding the alkaline reagent Na2CO3. Since the sodium carbonate is gradually released from the discs in pre-determined kinetics, it will ultimately compensate the decrease in pH caused by the biological activity of microorganisms.

Results

The controlled-release discs presented here were successfully used to cultivate E. coli K12 and E. coli BL21 pRSET eYFP-IL6 in mineral media with glucose and glycerol as carbon (C) sources, respectively. With glucose as the C-source it was possible to reduce the required buffer concentration in shake flask cultures by 50%. Moreover, with glycerol as the C-source, no buffer was needed at all.

Conclusions

These novel polymer-based controlled-release discs allowed buffer concentrations in shake flask media to be substantially reduced or omitted, while the pH remains in the physiological range of the microorganisms during the whole cultivation time. Therefore, the controlled-release discs allow a better control of the pH, than merely using high buffer concentrations. The conditions applied here, i.e. with significantly reduced buffer concentrations, enhance the comparability of the culture conditions used in screening experiments and large-scale fermentation processes.
Methicillin resistant Staphylococcus aureus adhesion to human umbilical vein endothelial cells demonstrates wall shear stress dependent behaviour
Authors: Viegas Kayla D , Dol Sharul S , Salek M Mehdi , Shepherd Robert D , Martinuzzi Robert M , Rinker Kristina D
Published: March 2011

Background

Methicillin-resistantStaphylococcus aureus(MRSA) is an increasingly prevalent pathogen capable of causing severe vascular infections. The goal of this work was to investigate the role of shear stress in early adhesion events.

Methods

Human umbilical vein endothelial cells (HUVEC) were exposed to MRSA for 15-60 minutes and shear stresses of 0-1.2 Pa in a parallel plate flow chamber system. Confocal microscopy stacks were captured and analyzed to assess the number of MRSA. Flow chamber parameters were validated using micro-particle image velocimetry (PIV) and computational fluid dynamics modelling (CFD).

Results

Under static conditions, MRSA adhered to, and were internalized by, more than 80% of HUVEC at 15 minutes, and almost 100% of the cells at 1 hour. At 30 minutes, there was no change in the percent HUVEC infected between static and low flow (0.24 Pa), but a 15% decrease was seen at 1.2 Pa. The average number of MRSA per HUVEC decreased 22% between static and 0.24 Pa, and 37% between 0.24 Pa and 1.2 Pa. However, when corrected for changes in bacterial concentration near the surface due to flow, bacteria per area was shown to increase at 0.24 Pa compared to static, with a subsequent decline at 1.2 Pa.

Conclusions

This study demonstrates that MRSA adhesion to endothelial cells is strongly influenced by flow conditions and time, and that MSRA adhere in greater numbers to regions of low shear stress. These areas are common in arterial bifurcations, locations also susceptible to generation of atherosclerosis.
Cystic cavernous malformation of the cerebellopontine angle: Case report and literature review
Authors: Huang Haiyan , Xu Kan , Qu Limei , Li Ye , Yu Jinlu
Published: March 2011

Background

Cavernous malformations (CMs) in the cerebellopontine angle (CPA) are rare, and most of such CMs reported to date are solid and extend from the internal auditory canal into the CPA. In contrast, cystic CMs that arise in the CPA and do not involve the internal auditory canal and dura of the skull base are extremely rare.

Case presentation

A 50-year-old man presented with vertigo and progressive hearing loss in the right ear. MRI examination revealed a lesion in the CPA with solid and cystic components. Surgery was performed. Well-circumscribed adhesion to cranial nerves, the cerebellum, or the brain stem was noted during surgery. The lesion was totally resected. Pathological examination suggested the lesion to be a CM. At 1-year follow-up, the symptoms at presentation had resolved and no complications had occurred.

Conclusion

Although cystic CMs of the CPA have no established imaging features, a diagnosis of CMs may be suspected when a cystic lesion is present in the CPA and does not involve internal acoustic meatus or dura mater of the skull base. Skillful microsurgical techniques and monitoring of cranial nerves will secure good outcomes for patients with cystic CMs in the CPA.
Severe teratozoospermia and its influence on pronuclear morphology, embryonic cleavage and compaction
Authors: Berger Dara S , AbdelHafez Faten , Russell Helena , Goldfarb James , Desai Nina
Published: March 2011

Background

Fertilization, cell division and embryo development depend on genomic contributions from male and female gametes. We hypothesize that teratozoospermic sperm influences early embryo development and embryo compaction.

Methods

We conducted a retrospective analysis of embryos derived from intracytoplasmic sperm injection (ICSI) cycles. Two hundred thirty-five consecutive ICSI cycles were included in the study; all treatment was provided at the Cleveland Clinic Fertility Center. Patient cycles were divided by sperm morphology based on Kruger's strict criteria: Group A, embryos where teratozoospermic sperm (0-2% normal) were used for ICSI and Group B, embryos where dysmorphic sperm (5-13% normal) were used for ICSI. All cycles analyzed were of patients doing day 3 embryo transfers. Outcome measures assessed included pronuclear (PN) pattern, syngamy, early cleavage, cell number, rate of compaction and blastulation of embryos left in culture and not transferred on day 3.

Results

A total of 1762 embryos were analyzed. PN patterns were similar in Group A and Group B embryos. No differences were noted in syngamy, cleavage, cell number or blastulation rate. Studying the development of embryos in culture after day 3 transfer revealed a difference in the timeline for compaction. By day 4, 25% of Group A embryos had compacted compared to 36% in Group B (P = 0.0007). There was no difference found between Group A and Group B embryos in regards to blastulation.

Conclusions

We did not find an association between sperm morphology and clinical outcomes. The impact of teratozoospermia may be masked in ICSI cycles where fertilization, implantation rate and clinical pregnancy rate are the primary outcome measures. However, by examining the timeline of development, we were better able to discern a potential paternal effect at critical transition points from fertilization through activation.
SERPINE2, an inhibitor of plasminogen activators, is highly expressed in the human endometrium during the secretory phase
Authors: Lee Robert Kuo-Kuang , Fan Chi-Chen , Hwu Yuh-Ming , Lu Chung-Hao , Lin Ming-Huei , Chen Ying-Jie , Li Sheng-Hsiang
Published: March 2011

Background

SERPINE2, also known as protease nexin-1, belongs to the serine protease inhibitor (SERPIN) superfamily. It is one of the potent SERPINs that modulates the activity of plasminogen activators (PAs). PAs and their SERPIN inhibitors, such as SERPINB2 and SERPINE1, were expressed in the human endometrium and were implicated in implantation. However, expression data about SERPINE2 in the human endometrium is still unknown. Thus, we conducted an investigation to reveal the spatiotemporal and cellular expression of SERPINE2 in the human uterus during the menstrual cycle.

Methods

Seven patients who underwent a hysterectomy and samples of 120 archived patients' endometrial curettage or parts of the uterus that were formalin-fixed and embedded in paraffin. Western blotting was performed to evaluate the specificity and sensitivity of the antibody. Immunohistochemistry was conducted to localize the SERPINE2 expression site. Quantitative analysis was conducted to evaluate expression levels of SERPINE2 in various sub-phases of the menstrual cycle.

Results

The SERPINE2 protein was primarily detected in the uterine fluid during the mid- and late-secretory phases of the menstrual cycle. It was predominantly expressed in the luminal and glandular epithelium, less in the myometrium, and only dispersedly in certain stromal cells throughout the menstrual cycle. A quantitative analysis of expression levels of SERPINE2 in the glandular epithelium revealed that it was highly expressed in the endometrium during the secretory phase compared to the proliferative phase.

Conclusions

The SERPINE2 protein is highly expressed in the endometrium during the secretory phase, indicating that it may participate in tissue remodeling involved in implantation.
High ERCC1 expression predicts cisplatin-based chemotherapy resistance and poor outcome in unresectable squamous cell carcinoma of head and neck in a betel-chewing area
Authors: Chiu Tai-Jan , Chen Chang-Han , Chien Chih-Yen , Li Shau-Hsuan , Tsai Hsin-Ting , Chen Yi-Ju
Published: March 2011

Background

This study was to evaluate the effect of excision repair cross-complementation group 1(ERCC1) expression on response to cisplatin-based induction chemotherapy (IC) followed by concurrent chemoradiation (CCRT) in locally advanced unresectable head and neck squamous cell carcinoma (HNSCC) patients.

Methods

Fifty-seven patients with locally advanced unresectable HNSCC who received cisplatin-based IC followed by CCRT from January 1, 2006 through January 1, 2008. Eligibility criteria included presence of biopsy-proven HNSCC without a prior history of chemotherapy or radiotherapy. Immunohistochemistry was used to assess ERCC1 expression in pretreatment biopsy specimens from paraffin blocks. Clinical parameters, including smoking, alcohol consumption and betel nuts chewing, were obtained from the medical records.

Results

The 12-month progression-free survival (PFS) and 2-year overall survival (OS) rates of fifty-seven patients were 61.1% and 61.0%, respectively. Among these patients, thirty-one patients had low ERCC1 expression and forty-one patients responded to IC followed by CCRT. Univariate analyses showed that patients with low expression of ERCC1 had a significantly higher 12-month PFS rates (73.3% vs. 42.3%, p < 0.001) and 2-year OS (74.2 vs. 44.4%, p = 0.023) rates. Multivariate analysis showed that for patients who did not chew betel nuts and had low expression of ERCC1 were independent predictors for prolonged survival.

Conclusions

Our study suggest that a high expression of ERCC1 predict a poor response and survival to cisplatin-based IC followed by CCRT in patients with locally advanced unresectable HNSCC in betel nut chewing area.
Can graphene make better HgCdTe infrared detectors?
Authors: Xu Wen , Gong Youpin , Liu Liwei , Qin Hua , Shi Yanli
Published: March 2011

We develop a simple and low-cost technique based on chemical vapor deposition from which large-size graphene films with 5-10 graphene layers can be produced reliably and the graphene films can be transferred easily onto HgCdTe (MCT) thin wafers at room temperature. The proposed technique does not cause any thermal and mechanical damages to the MCT wafers. It is found that the averaged light transmittance of the graphene film on MCT thin wafer is about 80% in the mid-infrared bandwidth at room temperature and 77 K. Moreover, we find that the electrical conductance of the graphene film on the MCT substrate is about 25 times larger than that of the MCT substrate at room temperature and 77 K. These experimental findings suggest that, from a physics point of view, graphene can be utilized as transparent electrodes as a replacement for metal electrodes while producing better and cheaper MCT infrared detectors.
Impairment of brain endothelial glucose transporter by methamphetamine causes blood-brain barrier dysfunction
Authors: Muneer P M Abdul , Alikunju Saleena , Szlachetka Adam M , Murrin L Charles , Haorah James
Published: March 2011

Background

Methamphetamine (METH), an addictive psycho-stimulant drug with euphoric effect is known to cause neurotoxicity due to oxidative stress, dopamine accumulation and glial cell activation. Here we hypothesized that METH-induced interference of glucose uptake and transport at the endothelium can disrupt the energy requirement of the blood-brain barrier (BBB) function and integrity. We undertake this study because there is no report of METH effects on glucose uptake and transport across the blood-brain barrier (BBB) to date.

Results

In this study, we demonstrate that METH-induced disruption of glucose uptake by endothelium lead to BBB dysfunction. Our data indicate that a low concentration of METH (20 μM) increased the expression of glucose transporter protein-1 (GLUT1) in primary human brain endothelial cell (hBEC, main component of BBB) without affecting the glucose uptake. A high concentration of 200 μM of METH decreased both the glucose uptake and GLUT1 protein levels in hBEC culture. Transcription process appeared to regulate the changes in METH-induced GLUT1 expression. METH-induced decrease in GLUT1 protein level was associated with reduction in BBB tight junction protein occludin and zonula occludens-1. Functional assessment of the trans-endothelial electrical resistance of the cell monolayers and permeability of dye tracers in animal model validated the pharmacokinetics and molecular findings that inhibition of glucose uptake by GLUT1 inhibitor cytochalasin B (CB) aggravated the METH-induced disruption of the BBB integrity. Application of acetyl-L-carnitine suppressed the effects of METH on glucose uptake and BBB function.

Conclusion

Our findings suggest that impairment of GLUT1 at the brain endothelium by METH may contribute to energy-associated disruption of tight junction assembly and loss of BBB integrity.
Full genome re-sequencing reveals a novel circadian clock mutation in Arabidopsis
Authors: Ashelford Kevin , Eriksson Maria E , Allen Christopher M , D'Amore Rosalinda , Johansson Mikael , Gould Peter , Kay Suzanne , Millar Andrew J , Hall Neil , Hall Anthony
Published: March 2011

Map based cloning in Arabidopsis thaliana can be a difficult and time-consuming process, specifically if the phenotype is subtle and scoring labour intensive. Here, we have re-sequenced the 120-Mb genome of a novel Arabidopsis clock mutant early bird (ebi-1) in Wassilewskija (Ws-2). We demonstrate the utility of sequencing a backcrossed line in limiting the number of SNPs considered. We identify a SNP in the gene AtNFXL-2 as the likely cause of the ebi-1 phenotype.
G-1-Activated Membrane Estrogen Receptors Mediate Increased Contractility of the Human Myometrium
Authors: Maiti K. , Paul J. W. , Read M. , Chan E. C. , Riley S. C. , Nahar P. , Smith R.
Published: March 2011

Estrogens are key mediators of increased uterine contractility at labor. We sought to determine whether membrane-associated estrogen receptors, such as the recently described seven-transmembrane receptor G protein-coupled receptor 30 (GPR30), mediated some of this effect. Using human myometrium obtained at term cesarean section before or after the onset of labor, we demonstrated the presence of GPR30 mRNA and protein using quantitative RT-PCR and Western blotting. GPR30 receptor was localized to the cell membrane and often colocalized with calveolin-1. Using the specific estrogen membrane receptor agonist G-1 and myometrial explants, we showed that membrane receptor activation led to phosphorylation of MAPK and the actin-modifying small heat shock protein 27. Using myometrial strips incubated with G-1 or vehicle we demonstrated that estrogen membrane receptor activation increased the myometrial contractile response to oxytocin. These data suggest that activation of the plasma membrane estrogen receptor GPR30 likely participates in the physiology of the human myometrium during pregnancy and identifies it as a potential target to modify uterine activity.
Lack of Dietary Carbohydrates Induces Hepatic Growth Hormone (GH) Resistance in Rats
Authors: Bielohuby Maximilian , Sawitzky Mandy , Stoehr Barbara J. M. , Stock Peggy , Menhofer Dominik , Ebensing Sabine , Bjerre Mette , Frystyk Jan , Binder Gerhard , Strasburger Christian , Wu Zida , Christ Bruno , Hoeflich Andreas , Bidlingmaier Martin
Published: March 2011

GH is a well established regulator of growth, lipid, and glucose metabolism and therefore important for fuel utilization. However, little is known about the effects of macronutrients on the GH/IGF system. We used low-carbohydrate/high-fat diets (LC-HFD) as a model to study the impact of fat, protein, and carbohydrates on the GH/IGF-axis; 12-wk-old Wistar rats were fed either regular chow, a moderate, protein-matched LC-HFD, or a ketogenic LC-HFD (percentage of fat/protein/carbohydrates: chow, 16.7/19/64.3; LC-HF-1, 78.7/19.1/2.2; LC-HF-2, 92.8/5.5/1.7). After 4 wk, body and tibia length, lean body mass, and fat pad weights were measured. Furthermore, we investigated the effects of LC-HFD on 1) secretion of GH and GH-dependent factors, 2) expression and signaling of components of the GH/IGF system in liver and muscle, and 3) hypothalamic and pituitary regulation of GH release. Serum concentrations of IGF-I, IGF binding protein-1, and IGF binding protein-3 were lower with LC-HF-1 and LC-HF-2 (P < 0.01). Both LC-HFD-reduced hepatic GH receptor mRNA and protein expression, decreased basal levels of total and phosphorylated Janus kinase/signal transducers and activators of transcription signaling proteins and reduced hepatic IGF-I gene expression. Hypothalamic somatostatin expression was reduced only with LC-HF-1, leading to increased pituitary GH secretion, higher IGF-I gene expression, and activation of IGF-dependent signaling pathways in skeletal muscle. In contrast, despite severely reduced IGF-I concentrations, GH secretion did not increase with LC-HF-2 diet. In conclusion, lack of carbohydrates in LC-HFD induces hepatic GH resistance. Furthermore, central feedback mechanisms of the GH/IGF system are impaired with extreme, ketogenic LC-HFD.
Flight restriction prevents associative learning deficits but not changes in brain protein-adduct formation during honeybee ageing
Authors: Tolfsen Christina C. , Baker Nicholas , Kreibich Claus , Amdam Gro V.
Published: March 2011

Honeybees (Apis mellifera) senesce within 2 weeks after they discontinue nest tasks in favour of foraging. Foraging involves metabolically demanding flight, which in houseflies (Musca domestica) and fruit flies (Drosophila melanogaster) is associated with markers of ageing such as increased mortality and accumulation of oxidative damage. The role of flight in honeybee ageing is incompletely understood. We assessed relationships between honeybee flight activity and ageing by simulating rain that confined foragers to their colonies most of the day. After 15 days on average, flight-restricted foragers were compared with bees with normal (free) flight: one group that foraged for ∼15 days and two additional control groups, for flight duration and chronological age, that foraged for ∼5 days. Free flight over 15 days on average resulted in impaired associative learning ability. In contrast, flight-restricted foragers did as well in learning as bees that foraged for 5 days on average. This negative effect of flight activity was not influenced by chronological age or gustatory responsiveness, a measure of the bees' motivation to learn. Contrasting their intact learning ability, flight-restricted bees accrued the most oxidative brain damage as indicated by malondialdehyde protein adduct levels in crude cytosolic fractions. Concentrations of mono- and poly-ubiquitinated brain proteins were equal between the groups, whereas differences in total protein amounts suggested changes in brain protein metabolism connected to forager age, but not flight. We propose that intense flight is causal to brain deficits in aged bees, and that oxidative protein damage is unlikely to be the underlying mechanism.
A simple technique to manipulate foraging costs in seed-eating birds
Authors: Koetsier Egbert , Verhulst Simon
Published: March 2011

Food availability is a key factor in ecology and evolution, but available techniques to manipulate the effort to acquire food in vertebrates are technically challenging and/or labour intensive. We present a simple technique to increase foraging costs in seed-eating birds that can be applied with little effort and at low monetary cost for prolonged periods (years) to solitary or group-housed animals. The essence of the technique is that food is offered in a container above ground level, with holes in the sides from which the food can be taken, forcing birds into energetically demanding hovering flight to forage. As a control treatment we offered a similar container but with perches mounted beneath the holes, allowing birds to eat without extra flights. Increasing foraging costs in this way induced zebra finches to double the time spent foraging, and to decrease their basal metabolic rate, in agreement with results obtained using more laborious techniques to increase foraging costs. The technique was not too severe because mortality was low during a winter with sub-zero temperatures. As foraging costs under natural conditions are generally higher than those under standard laboratory conditions, we suggest that measuring behaviour and physiology when animals have to work for food may better reflect their natural state.
Ocellar adaptations for dim light vision in a nocturnal bee
Authors: Berry Richard P. , Wcislo William T. , Warrant Eric J.
Published: March 2011

Growing evidence indicates that insect ocelli are strongly adapted to meet the specific functional requirements in the environment in which that insect lives. We investigated how the ocelli of the nocturnal bee Megalopta genalis are adapted to life in the dim understory of a tropical rainforest. Using a combination of light microscopy and three-dimensional reconstruction, we found that the retinae contain bar-shaped rhabdoms loosely arranged in a radial pattern around multi-layered lenses, and that both lenses and retinae form complex non-spherical shapes reminiscent of those described in other ocelli. Intracellular electrophysiology revealed that the photoreceptors have high absolute sensitivity, but that the threshold location varied widely between 109 and 1011 photons cm–2 s–1. Higher sensitivity and greater visual reliability may be obtained at the expense of temporal resolution: the corner frequencies of dark-adapted ocellar photoreceptors were just 4–11 Hz. Spectral sensitivity profiles consistently peaked at 500 nm. Unlike the ocelli of other flying insects, we did not detect UV-sensitive visual pigments in M. genalis, which may be attributable to a scarcity of UV photons under the rainforest canopy at night. In contrast to earlier predictions based on anatomy, the photoreceptors are not sensitive to the e-vector of polarised light. Megalopta genalis ocellar photoreceptors possess a number of unusual properties, including inherently high response variability and the ability to produce spike-like potentials. These properties bear similarities to photoreceptors in the compound eye of the cockroach, and we suggest that the two insects share physiological characteristics optimised for vision in dim light.
Regulatory function of hyperosmotic stress-induced signaling cascades in the expression of transcription factors and osmolyte transporters in freshwater Japanese eel primary gill cell culture
Authors: Chow S. C. , Wong Chris K. C.
Published: March 2011

In the present study, we investigated the early activation of osmotic stress-related protein kinases, with the aim of characterizing their functional links with downstream effectors (i.e. transcription factors and osmolyte transporters). Freshwater eel primary gill cells were cultured in hypertonic medium (500 mosmol l–1) for 6 h. Protein lysates and total RNA were collected for western blotting and quantitative real-time PCR assays. In this study, the osmotic challenge stimulated histone H3 phosphorylation, various signaling pathways (i.e. ERK1/2, p38 MAPK, JNK, CREB, MARCKS and MLCK) and expression of some downstream effectors (i.e. Na+/K+-ATPase, TauT and Ostf). Increased phosphorylation of acetylated histone is known to promote chromatin relaxation for global gene transcription, probably leading to the activation of downstream effectors for osmotic responses. In addition, the importance of the p38 MAPK and MLCK pathways in the regulation of the expression of Na+/K+-ATPase and TauT was demonstrated. Inhibition of the p38 MAPK pathway by SB202190 reduced histone H3 phosphorylation and TauT mRNA expression. Moreover, inhibition of the MLCK pathway by ML-7 decreased the expression level of Na+/K+-ATPase but increased the transcript level of TauT. Collectively, the present study reveals possible functional links of osmosensing signaling cascades to the regulation of downstream effectors.
Flower constancy in honey bee workers (Apis mellifera) depends on ecologically realistic rewards
Authors: Grüter Christoph , Moore Heather , Firmin Nicola , Helanterä Heikki , Ratnieks Francis L. W.
Published: March 2011

As first described by Aristotle, honey bee (Apis mellifera) workers show a strong tendency to visit flowers of only one type during a foraging trip. It is known that workers rapidly learn a flower colour when rewarded with artificial nectar (sucrose solution). However, some previous studies report that the degree of constancy after training is unaffected by reward quantity and quality when bees are tested in an array of artificial flowers of two easily distinguished colours, such as blue and yellow. One possible reason for this surprising result is that large reward volumes were compared. This is likely to mask the abilities of foragers to make adaptive decisions under more realistic conditions. To test this possibility, we offered untrained honey bee workers ecologically relevant rewards (0.5, 1 or 2 μl of 0.5 or 1 mol l–1 sucrose solution) on one or two consecutive yellow or blue artificial flowers and then recorded which flowers the bees subsequently landed on in an array of 40 empty flowers. The results showed that an increase in all three factors (volume, concentration and number of rewards) significantly increased constancy (proportion of visits to flowers of the trained colour) and persistence (number of flowers visited) during the foraging bout. Constancy for the least rewarding situation was 75.9% compared with 98.6% for the most rewarding situation. These results clearly show that honey bee workers do become more constant to blue or yellow with increasing nectar rewards, provided that the rewards used are ecologically realistic. As the most rewarding conditions led to nearly 100% constancy, further reward increases during training would not have been able to further increase constancy. This explains why previous studies comparing large rewards found no effect of reward on constancy.
Slipping, sliding and stability: locomotor strategies for overcoming low-friction surfaces
Authors: Clark Andrew J. , Higham Timothy E.
Published: March 2011

Legged terrestrial animals must avoid falling while negotiating unexpected perturbations inherent to their structurally complex environments. Among humans, fatal and nonfatal injuries frequently result from slip-induced falls precipitated by sudden unexpected encounters with low-friction surfaces. Although studies using walking human models have identified some causes of falls and mechanisms underlying slip prevention, it is unclear whether these apply to various locomotor speeds and other species. We used high-speed video and inverse dynamics to investigate the locomotor biomechanics of helmeted guinea fowl traversing slippery surfaces at variable running speeds (1.3–3.6 m s–1). Falls were circumvented when limb contact angles exceeded 70 deg, though lower angles were tolerated at faster running speeds (>3.0 m s–1). These prerequisites permitted a forward shift of the body's center of mass over the limb's base of support, which kept slip distances below 10 cm (the threshold distance for falls) and maximized the vertical ground reaction forces, thus facilitating limb retraction and the conclusion of the stance phase. These postural control strategies for slip avoidance parallel those in humans, demonstrating the applicability of these strategies across locomotor gaits and the potential for guinea fowl as an insightful model for invasive approaches to understanding limb neuromuscular control on slippery surfaces.
Burrowing and subsurface locomotion in anguilliform fish: behavioral specializations and mechanical constraints
Authors: Herrel Anthony , Choi Hon Fai , Dumont Elizabeth , De Schepper Natalie , Vanhooydonck Bieke , Aerts Peter , Adriaens Dominique
Published: March 2011

Fish swimming is probably one of the most studied and best understood locomotor behaviors in vertebrates. However, many fish also actively exploit sediments. Because of their elongate body shape, anguilliform fishes are not only efficient swimmers but also very maneuverable. Consequently, many species live in complexly structured environments near the bottom and many are known to burrow into the sediment. To better understand burrowing and subsurface locomotion in anguilliform fish we provide descriptive kinematic data on subsurface locomotion in a burrowing eel (Pisodonophis boro) using videofluoroscopy. We also measured the maximal forces that can be exerted by this species during head-first and tail-first burrowing, and explored the implications of head-first burrowing on mechanical stress distribution in the skull. Our data show that P. boro uses lateral undulation to penetrate and move in sandy sediments under water. The kinematics of subsurface locomotion are different from those observed during swimming and are characterized by a very high slip factor. These observations differ considerably from recently published data in terrestrial sand-swimming lizards, and suggest that the sediment behaves like a solid rather than a frictional fluid. Finally, our finite element models show that the cranial shape and structure in the head-first burrowing P. boro is mechanically more suited for head-first burrowing than that of an obligate tail-first burrowing species, Heteroconger hassi.