bluuebunny/crossref_metadata_2025 huggingface dataset:
Risk of breast cancer following exposure to tetrachloroethylene-contaminated drinking water in Cape Cod, Massachusetts: reanalysis of a case-control study using a modified exposure assessment
Authors: Gallagher Lisa G , Vieira Veronica M , Ozonoff David , Webster Thomas F , Aschengrau Ann
Published: May 2011

Background

Tetrachloroethylene (PCE) is an important occupational chemical used in metal degreasing and drycleaning and a prevalent drinking water contaminant. Exposure often occurs with other chemicals but it occurred alone in a pattern that reduced the likelihood of confounding in a unique scenario on Cape Cod, Massachusetts. We previously found a small to moderate increased risk of breast cancer among women with the highest exposures using a simple exposure model. We have taken advantage of technical improvements in publically available software to incorporate a more sophisticated determination of water flow and direction to see if previous results were robust to more accurate exposure assessment.

Methods

The current analysis used PCE exposure estimates generated with the addition of water distribution modeling software (EPANET 2.0) to test model assumptions, compare exposure distributions to prior methods, and re-examine the risk of breast cancer. In addition, we applied data smoothing to examine nonlinear relationships between breast cancer and exposure. We also compared a set of measured PCE concentrations in water samples collected in 1980 to modeled estimates.

Results

Thirty-nine percent of individuals considered unexposed in prior epidemiological analyses were considered exposed using the current method, but mostly at low exposure levels. As a result, the exposure distribution was shifted downward resulting in a lower value for the 90th percentile, the definition of "high exposure" in prior analyses. The current analyses confirmed a modest increase in the risk of breast cancer for women with high PCE exposure levels defined by either the 90th percentile (adjusted ORs 1.0-1.5 for 0-19 year latency assumptions) or smoothing analysis cut point (adjusted ORs 1.3-2.0 for 0-15 year latency assumptions). Current exposure estimates had a higher correlation with PCE concentrations in water samples (Spearman correlation coefficient = 0.65, p < 0.0001) than estimates generated using the prior method (0.54, p < 0.0001).

Conclusions

The incorporation of sophisticated flow estimates in the exposure assessment method shifted the PCE exposure distribution downward, but did not meaningfully affect the exposure ranking of subjects or the strength of the association with the risk of breast cancer found in earlier analyses. Thus, the current analyses show a slightly elevated breast cancer risk for highly exposed women, with strengthened exposure assessment and minimization of misclassification by using the latest technology.
Defining Socially-Based Spatial Boundaries in the Region of Peel, Ontario, Canada
Authors: Drackley Adam , Newbold KBruce , Taylor Christian
Published: May 2011

Background

The purpose of the project was to delineate a series of contiguous neighbourhood-based "Data Zones" within the Region of Peel (Ontario) for the purpose of health data analysis and dissemination. Zones were to be built on Census Tracts (N = 205) and obey a series of requirements defined by the Region of Peel. This paper explores a method that combines statistical analysis with ground-truthing, consultation, and the use of a decision tree.

Data

Census Tract data for Peel were derived from the 2006 Canadian Census Master file.

Methods

Following correlation analysis to reduce the data set, Principal Component Analysis was applied to the data set to reduce the complexity and derive an index. The Getis-Ord Gi*statistic was then applied to look for statistically significant clusters of like Census Tracts. A detailed decision tree for the amalgamation of remaining zones and ground-truthing with Peel staff verified the resulting zones.

Results

A total of 15 Data Zones that are similar with respect to socioeconomic and sociodemographic attributes and that met criteria defined by Peel were derived for the region.

Conclusion

The approach used in this analysis, which was bolstered by a series of checks and balances throughout the process, gives statistical validity to the defined zones and resulted in a robust series of Data Zones for use by Peel Public Health. We conclude by offering insight into alternative uses of the methodology, and limitations.
The combined transduction of copper, zinc-superoxide dismutase and catalase mediated by cell-penetrating peptide, PEP-1, to protect myocardium from ischemia-reperfusion injury
Authors: Huang Guang-Qing , Wang Jia-Ning , Tang Jun-Ming , Zhang Lei , Zheng Fei , Yang Jian-Ye , Guo Ling-Yun , Kong Xia , Huang Yong-Zhang , Liu Yong , Chen Shi-You
Published: May 2011

Background

Our previous studies indicate that either PEP-1-superoxide dismutase 1 (SOD1) or PEP-1-catalase (CAT) fusion proteins protects myocardium from ischemia-reperfusion-induced injury in rats. The aim of this study is to explore whether combined use of PEP-1-SOD1 and PEP-1-CAT enhances their protective effects.

Methods

SOD1, PEP-1-SOD1, CAT or PEP-1-CAT fusion proteins were prepared and purified by genetic engineering. In vitro and in vivo effects of these proteins on cell apoptosis and the protection of myocardium after ischemia-reperfusion injury were measured. Embryo cardiac myocyte H9c2 cells were used for the in vitro studies. In vitro cellular injury was determined by the expression of lactate dehydrogenase (LDH). Cell apoptosis was quantitatively assessed with Annexin V and PI double staining by Flow cytometry. In vivo, rat left anterior descending coronary artery (LAD) was ligated for one hour followed by two hours of reperfusion. Hemodynamics was then measured. Myocardial infarct size was evaluated by TTC staining. Serum levels of myocardial markers, creatine kinase-MB (CK-MB) and cTnT were quantified by ELISA. Bcl-2 and Bax expression in left ventricle myocardium were analyzed by western blot.

Results

In vitro, PEP-1-SOD1 or PEP-1-CAT inhibited LDH release and apoptosis rate of H9c2 cells. Combined transduction of PEP-1-SOD1 and PEP-1-CAT, however, further reduced the LDH level and apoptosis rate. In vivo, combined usage of PEP-1-SOD1 and PEP-1-CAT produced a greater effect than individual proteins on the reduction of CK-MB, cTnT, apoptosis rate, lipoxidation end product malondialdehyde, and the infarct size of myocardium. Functionally, the combination of these two proteins further increased left ventricle systolic pressure, but decreased left ventricle end-diastolic pressure.

Conclusion

This study provided a basis for the treatment or prevention of myocardial ischemia-reperfusion injury with the combined usage of PEP-1-SOD1 and PEP-1-CAT fusion proteins.
Intramuscular immunization of mice with live influenza virus is more immunogenic and offers greater protection than immunization with inactivated virus
Authors: Harris Katie , Ream Rebecca , Gao Jin , Eichelberger Maryna C
Published: May 2011

Background

Influenza virus continues to cause significant hospitalization rates in infants and young children. A 2-dose regime of trivalent inactivated vaccine is required to generate protective levels of hemagglutination inhibiting (HAI) antibodies. A vaccine preparation with enhanced immunogenicity is therefore desirable.

Methods

Mice were inoculated intramuscularly (IM) with live and inactivated preparations of A/Wisconsin/67/2005 (H3N2). Serum cytokine levels, hemagglutinin (HA)-specific antibody responses and nucleoprotein (NP)-specific CD8+ T cell responses were compared between vaccinated groups, as well as to responses measured after intranasal infection. The protective efficacy of each vaccine type was compared by measuring virus titers in the lungs and weight loss of mice challenged intranasally with a heterosubtypic virus, A/PR/8/34 (H1N1).

Results

Intramuscular administration of live virus resulted in greater amounts of IFN-α, IL-12 and IFN-γ, HA-specific antibodies, and virus-specific CD8+ T cells, than IM immunization with inactivated virus. These increases corresponded with the live virus vaccinated group having significantly less weight loss and less virus in the lungs on day 7 following challenge with a sublethal dose of a heterosubtypic virus.

Conclusions

Inflammatory cytokines, antibody titers to HA and CD8+ T cell responses were greater to live than inactivated virus delivered IM. These increased responses correlated with greater protection against heterosubtypic virus challenge, suggesting that intramuscular immunization with live influenza virus may be a practical means to increase vaccine immunogenicity and to broaden protection in pediatric populations.
Use of Tranexamic acid is a cost effective method in preventing blood loss during and after total knee replacement
Authors: Sepah Yasir J , Umer Masood , Ahmad Tashfeen , Nasim Faria , Umer Chaudhry Muhammad , Umar Muhammad
Published: May 2011

Background & Purpose

Allogenic blood transfusion in elective orthopaedic surgery is best avoided owing to its associated risks. Total knee replacement often requires blood transfusion, more so when bilateral surgery is performed. Many strategies are currently being employed to reduce the amount of peri-operative allogenic transfusions. Anti-fibrinolytic compounds such as aminocaproic acid and tranexamic acid have been used systemically in perioperative settings with promising results. This study aimed to evaluate the effectiveness of tranexamic acid in reducing allogenic blood transfusion in total knee replacement surgery.

Methodology

This was a retrospective cohort study conducted on patients undergoing total knee replacement during the time period November 2005 to November 2008. Study population was 99 patients, of which 70 underwent unilateral and 29 bilateral knee replacement. Forty-seven patients with 62 (49.5%) knees (group-I) had received tranexamic acid (by surgeon preference) while the remaining fifty-two patients with 66 (51.5%) knees (group-II) had did not received any tranexamic acid either pre- or post-operatively.

Results

The mean drop in the post-operative haemoglobin concentration in Group-II for unilateral and bilateral cases was 1.79 gm/dl and 2.21 gm/dl, with a mean post-operative drainage of 1828 ml (unilateral) and 2695 ml (bilateral). In comparison, the mean drop in the post-op haemoglobin in Group-I was 1.49 gm/dl (unilateral) and 1.94 gm/dl (bilateral), with a mean drainage of 826 ml (unilateral) and 1288 ml (bilateral) (p-value < 0.001).

Interpretation

Tranexamic acid is effective in reducing post-operative drainage and requirement of blood transfusion after knee replacement.
Gangrenous cholecystitis in an asymptomatic patient found during an elective laparoscopic cholecystectomy: a case report
Authors: Chaudhry Sunil , Hussain Rima , Rajasundaram Rajaganeshan , Corless David
Published: May 2011

Introduction

Gangrenous cholecystitis is a severe complication of acute cholecystitis. We present an unusual case of gangrenous cholecystitis which was totally asymptomatic, with normal pre-operative parameters, and was discovered incidentally during a laparoscopic cholecystectomy. We have not found any similar cases in the published literature.

Case presentation

A 79-year-old British Caucasian man presented initially with acute cholecystitis which responded to conservative management. After six weeks he was asymptomatic and had normal blood parameters. An elective laparoscopic cholecystectomy was performed and our patient was found to have a totally gangrenous gall bladder.

Conclusion

It is important to keep a high index of suspicion for the diagnosis of gangrenous cholecystitis in order to avoid potentially serious complications.
piRNA profiling during specific stages of mouse spermatogenesis
Authors: Gan Haiyun , Lin Xiwen , Zhang Zhuqiang , Zhang Wei , Liao Shangying , Wang Lixian , Han Chunsheng
Published: May 2011

PIWI-interacting RNAs (piRNAs) are a class of small RNAs abundantly expressed in animal gonads. piRNAs that map to retrotransposons are generated by a “ping-pong” amplification loop to suppress the activity of retrotransposons. However, the biogenesis and function of other categories of piRNAs have yet to be investigated. In this study, we first profiled the expression of small RNAs in type A spermatogonia, pachytene spermatocytes, and round spermatids by deep sequencing. We then focused on the computational analysis of the potential piRNAs generated in the present study as well as other published sets. piRNAs mapping to retrotransposons, mRNAs, and intergenic regions had different length distributions and were differentially regulated in spermatogenesis. piRNA-generating mRNAs (PRMRs), whose expression positively correlated with their piRNA products, constituted one-third of the protein-coding genes and were evolutionarily conserved and enriched with splicing isoforms and antisense transcripts. PRMRs with piRNAs preferentially mapped to CDSs and 3′ UTRs partitioned into three clusters differentially expressed during spermatogenesis and enriched with unique sets of functional annotation terms related to housekeeping activities as well as spermatogenesis-specific processes. Intergenic piRNAs were divided into 2992 clusters probably representing novel transcriptional units that have not been reported. The transcripts of a large number of genes involved in spermatogenesis are the precursors of piRNAs, and these genes are intricately regulated by alternative splicing and antisense transcripts. piRNAs, whose regulatory role in gene expression awaits to be identified, are clearly products of a novel regulatory process that needs to be defined.
Differentiating analogous tRNA methyltransferases by fragments of the methyl donor
Authors: Lahoud Georges , Goto-Ito Sakurako , Yoshida Ken-ichi , Ito Takuhiro , Yokoyama Shigeyuki , Hou Ya-Ming
Published: May 2011

Bacterial TrmD and eukaryotic-archaeal Trm5 form a pair of analogous tRNA methyltransferase that catalyze methyl transfer from S-adenosyl methionine (AdoMet) to N1 of G37, using catalytic motifs that share no sequence or structural homology. Here we show that natural and synthetic analogs of AdoMet are unable to distinguish TrmD from Trm5. Instead, fragments of AdoMet, adenosine and methionine, are selectively inhibitory of TrmD rather than Trm5. Detailed structural information of the two enzymes in complex with adenosine reveals how Trm5 escapes targeting by adopting an altered structure, whereas TrmD is trapped by targeting due to its rigid structure that stably accommodates the fragment. Free energy analysis exposes energetic disparities between the two enzymes in how they approach the binding of AdoMet versus fragments and provides insights into the design of inhibitors selective for TrmD.
Making and Unmaking: The Achaean Wall and the Limits of Fictionality in Homeric Criticism
Authors: Porter James I.
Published: May 2011

The Achaean wall is a curious object that appears in Iliad 7 only to disappear in book 12 with a vehemence that is unique in the Homeric landscape. Puzzling in every other respect, is the wall even a single, coherent object? While the Alexandrians and their successors accepted Nestor's proposal and the construction of the wall as genuinely Homeric, modern critics of the analytic persuasion assume it must be an interpolation. This essay takes its cues from the ancient sources, which I believe indicate the most fruitful way of reading the episode and the wall generally—namely, as an object lesson in Homeric fictionality and its limits in the minds of successive readers of the Homeric poems.
Women's Work: Female Transmission of Mythical Narrative
Authors: Heath John
Published: May 2011

The role of women storytellers and singers in promulgating classical myth in antiquity is, admittedly, difficult to determine, and some scholars dismiss entirely the notion that female popular narrative included traditional tales. When looked at in its entirety, however, the evidence strongly suggests that women told the same kinds of mythological tales—both to themselves and children—as those found in "higher" genres. This finding complicates the already difficult challenge of determining the lineage of mythological tales found in epic and tragedy, a complexity that Ovid may playfully acknowledge in his own collection of myth.
Empire and the Limits of Analogy: Aztecs and Romans in Malibu
Authors: Martelli Francesca
Published: May 2011

This review discusses the politics of museum display evinced by an exhibition of Aztec artifacts held at the Getty Villa in Spring 2010. I argue that the curators draw on the comparative agenda of the sixteenth-century Spanish conquistadors, whose attempts at cultural assimilation are put on display, in order to pursue a form of cultural imperialism of their own. I point to the fault lines that appear in their attempts to illustrate the analogies drawn by the Spanish between the unfamiliar religious culture of the Aztec world and the religious system of ancient Rome, by juxtaposing the Aztec exhibits on loan with Roman artifacts contained in the Getty's permanent collection. I also explore some of the tensions produced by the decision to host the cultural heritage of Los Angeles' vast Mexican population in Getty's shrine to Greco-Roman antiquity. The particular set of juxtapositions presented to viewers at this exhibition exposes the power of the New World museum to fabricate a cultural myth of origin for its patrons at the expense of the cultural heritage of those displaced.
Bubble-Wrapped Children and Safe Books for Boys: The Politics of Parenting in Harry Potter
Authors: Winters Sarah Fiona
Published: May 2011

Harry Potter performs the same cultural work as contemporary popular discourse on parenting by suggesting that children can be set free to have adventures without risking death, since the young people who die in the series are never killed in accidents but only as a result of fighting evil.
"Telling Outrageous Marvels": Henry Morley's Baroque Victorian Fairy Tales
Authors: Fowler James
Published: May 2011

A thoroughly English author intensely involved in the period's issues, Morley brought to his work a keen social conscience balanced by an equally assertive fancy bordering on anarchic glee. In his tales we detect a tipping point that heralds Lewis Carroll's brilliant Alice campaign against straitlaced manners and morals.
Positive Aspects of International Student Transitions: A Qualitative Inquiry
Authors: Moores Lisa , Popadiuk Natalee
Published: May 2011

Despite the considerable growth of the international student population, positive aspects of their experience have received little attention. The current study combines a Critical Incident Technique methodology and a positive psychology lens to explore the cross-cultural transition of seven international students, focusing on facilitative factors, growth, and personal resources. Eight categories of helpful factors emerged from the 134 critical incidents recounted in the interviews: Growth and/or change, social support/building relationships, learning to navigate host culture, enjoyable activities outside of schoolwork, previous experiences and preparation, supportive faculty and staff, persevering through hard times, and a sense of belonging.
Emily Dickinson's Henry James
Authors: Wichelns Kathryn
Published: May 2011

The year after the 1878 publication of Henry James's The Europeans , Emily Dickinson refers to the novel or its author twice in her epistolary writing. This article suggests that her two evocations of James provide further insights into the poet's relationships with the recipients of the letters, Elizabeth Holland and Thomas Wentworth Higginson. Writing Holland, Dickinson deploys characters from The Europeans sympathetically, in a complex articulation of the necessity of women's spiritual and artistic self-determination. Her letter to Higginson is a response to his Short Studies of American Authors ; the poet seems to recognize that Higginson's objections to James's style echo his advice about her own work. Throughout his critical corpus and in his essay on James in Short Studies , Higginson conflates heteronormative ideals of gender with literary quality and true American citizenship. In these letters, Dickinson uses James and his characters to complicate the specifically gendered notions (of behavior, of style, of authorial citizenship) important to these correspondents.
Archangels, Magical Amulets, and the Defense of Late Antique Miletus
Authors: Cline Rangar H.
Published: May 2011

This study challenges Deissmann’s authoritative interpretation and dating of the archangel inscription on the ancient theater of Miletus (CIG 2.2895). Deissmann maintained that the inscription was clearly Christian and from the sixth century, after the conversion of the theater into a citadel. This study argues that the inscription is not distinctively Christian and probably dates from the fourth or fifth century. Recent archaeological research indicates that the conversion of the theater into a citadel occurred in the seventh, rather than in the sixth century. Thus, the palaeographical characteristics of the inscription can be explained only if the inscription originated earlier than the conversion of the theater. This earlier date suggests that the purpose of the inscription was probably not magical protection from military foes but rather protection from plague or other diseases. An analysis of a selection of magical gems demonstrates that the ovals of the inscription bear a significant resemblance to ovoid protective magical amulets from the late Roman period. The study concludes that an inscription long held to be Justinianic and Christian is most likely neither.
“With a Pure Heart and a Truthful Tongue”: The Recovery of the Text of the Manichaean Daily Prayers
Authors: Gardner Iain
Published: May 2011

Much progress has been made in the understanding of Manichaeism as a major religion in Late Antiquity, the recovery of its texts and practices, and tracking the remarkable spread of the community from its origins in early Sasanian Iran both westward into the Mediterranean world of the Late Roman Empire and east through Central Asia to its final demise in southern China. The religion had a unique record in terms of the extent of its distribution and its interaction with the governments, cultures, and faiths of the ancient and medieval worlds. Nevertheless, questions have remained about the unity of the tradition over such a large area and time period. This study proposes to recover the authentic text of the Manichaean daily prayers from a combination of previously available and recently discovered or edited sources. These sources derive from three very diverse cultural contexts: fourth-century Roman Egypt (in Greek), the tenth-century Abbasid empire (in Arabic), and early medieval Central Asia (in Middle Iranian). It will be shown that the text of the prayers remained remarkably constant as a fundamental pillar of the religious practice of this community deriving from Mani himself and an Aramaic original. This study of the Manichaean prayers provides insights both into our reading of Mani’s own religious identity and into our knowledge of the ritual life of a community where the teachings have been much better understood than the practices. It also suggests provocative questions about the impact of this tradition on the broader history and development of religions, especially as a precursor of Islam, which more famously came to dominate the heartland and trade routes of Eurasia in succession to it.
Law and Legal Documents in the Sermons of Peter Chrysologus
Authors: Ristuccia Nathan J.
Published: May 2011

Because Peter Chrysologus preached at the capital of Ravenna during the reign of Valentinian III, his large corpus of extant sermons provides an intriguing look at ideas and attitudes widely known at the center of the empire. This study will examine just one group of images common in these sermons: the language of law and documentation. The bishop demonstrates a surprisingly accurate knowledge of Roman law, and uses this knowledge to make his sermons understandable and relevant to his congregation. Chrysologus’ imagery can be read as a commentary and critique on imperial legal culture at the time of promulgation of the Theodosian Code.
Helping People to Manage and Share Their Digital Information: A Role for Public Libraries
Authors: Copeland Andrea J. , Barreau Deborah
Published: May 2011

As a cultural institution, the public library is charged with providing resources and services that fit the needs of a particular community and, if space and budgets allow, of serving as a resource and repository of the community's past. To fulfill its mission to the public, the library must attract that public by offering materials and providing opportunities for them to pursue their unique and varied interests and discover new things. By engaging individuals in the identification and preservation of their own personal, digital objects, it may be possible to increase awareness in, and commitment to, community repositories that reflect a community's diversity and that will serve all. A user education program that focuses on the importance of identifying and preserving the information and artifacts that are important, that addresses the technical aspects of preservation, and that creates awareness of the benefits and challenges associated with sharing personal information can result in a community repository that ultimately has more value for both the individual and the community.
Approaching the Anti-Collection
Authors: Martens Betsy Van der Veer
Published: May 2011

This conceptual article explores similarities and differences among libraries, archives, and museums (LAMs) and significant sectors of what Atkinson termed "the anti-collection" in order to better understand the evolving universe of digital publication and its possibilities.
Domesticating Modernity: Kinimatografikós Astír , the Work of the Imagination, and the Emergence of a National Cinema Culture, 1924–1927
Authors: Hess Franklin
Published: May 2011

The year 1924 marks a milestone in the history of Greek film: the birth of a distinctly national film culture as cosmopolitan Greeks and cosmopolitan-identified Greeks in the countryside engaged with the medium of film in order to imagine both the modernity of the contemporary world and their relationship to it. The periodical Kinimatografikós Astír played a key role in the emergence of this new film culture, facilitating its transformation into a movement. As a medium, cinema offered Greece a fresh start: an opportunity to heal internal schisms and rebuild the nation's stature around the world following the disastrous Asia Minor Campaign. Cinema, however, was not without its foes. Film eventually became a terrain of contestation in which modern and counter-modern sectors of Greek society struggled for superiority. Cinema was emerging as a mature medium, capable of altering the social and political status quo by exposing audiences to alternative social realities and allowing them to imagine new political possibilities.
Anti-Müllerian hormone confirms the novel classification of female functional androgenization including polycystic ovary syndrome
Authors: Wetzka B , Textor W , Ochsner A , Geisthövel F
Published: May 2011

Objective

Functional androgenization (FA) can be divided into five groups corresponding to the predominant organ pathology as recently shown by our group: functional cutaneous androgenization (FCA, skin) and FA syndrome (FAS) I (ovary, lean individual), II (adrenal gland), III (ovary, fat tissue, pancreas, and hyperinsulinemia), and IV (residual FA dysfunctions). Group-specific clusters are based on primary variables such as LH, testosterone, DHEAS, sex hormone-binding globulin (SHBG), body mass index (BMI), glucose, insulin, and enlarged polyfollicular ovaries. Because anti-Müllerian hormone (AMH) positively correlates with the antral follicle count, its relevance as an additional primary variable for classifying FA was investigated.

Design

In this study, 178 patients with FA were consecutively enrolled and classified into the five FA groups as described earlier and 30 women with regular menstrual cycles served as control.

Methods

Primary variables and serum AMH were analyzed in the early follicular phase.

Results

FA patients showed significantly elevated AMH levels (11.1±6.7 ng/ml) versus control (3.0±2.0 ng/ml; P<.0001). AMH was significantly increased in groups FAS I (15.6±5.8 ng/ml) and FAS III (11.6±6.6 ng/ml) compared with groups FCA (7.0±3.8 ng/ml), FAS II (5.05±3.0 ng/ml), and FAS IV (6.9±4.6 ng/ml) and correlated positively (P<.0001) with LH (r=0.538) and testosterone (r=0.368). In regression and multivariate analyses, AMH was not dependent on SHBG, DHEAS, BMI, glucose, or insulin. In receiver operating characteristic analysis, 9.21 ng/ml AMH showed 90% specificity with 71.2% sensitivity for the diagnosis of the two ovarian FA groups, FAS I and III.

Conclusion

AMH confirms the novel stratification system and constitutes a useful primary variable in the algorithm of FA classification.
The Endocrine Society's Clinical Practice Guideline on endocrine and nutritional management of the post-bariatric surgery patient: Commentary from a European Perspective
Authors: Torres Antonio J , Rubio Miguel A
Published: May 2011

Bariatric and metabolic surgery is experiencing a noteworthy increase worldwide in recent years, but protocols and consensus published in the past decade have not yet established clear evidence-based clinical recommendations. The Endocrine Society, with the participation of theEuropean Society of Endocrinology, has promoted the creation of an expert panel to propose a clinical practice guideline for postoperative management of patients, candidates to bariatric surgery, that places a particular emphasis on evidence-based medical aspects. The main arguments reflected in those recommendations are set out in this article and are subject to analysis and discussion from the specific viewpoint of the current European experience.
Glucocorticoid receptor-mediated apoptosis: mechanisms of resistance in cancer cells
Authors: Schlossmacher George , Stevens Adam , White Anne
Published: May 2011

Glucocorticoids (Gcs) are commonly used to treat patients suffering from a wide range of cancers. Their main therapeutic role is based on Gc receptor (GR)-mediated mechanisms that trigger cell death but this varies depending on the cancer type. This review aims to provide an overview of the mechanisms of Gc-induced cell death and more importantly the changes in GR that lead to resistance to Gc treatment in cancer. The three main cancer types, which are susceptible to Gc resistance and therefore loss of Gc-induced apoptotic effects, are acute lymphoblastic leukaemia, osteosarcoma and small-cell lung carcinoma. A common theme is the loss of GR function and/or a downregulation of GR expression which leads to failure of the cell death-inducing effects of Gcs. Loss of GR function is attributed to mutations in the GR gene, and in some cases a dominant-negative effect on any functional GR still present. The downregulation of GR expression can be due to decreased GR promoter activation, increased GR promoter methylation or increased expression of alternative splice isoforms of GR that have decreased transcriptional activity. Understanding the mechanisms behind Gc-triggered apoptosis and the resistance to it in these cancer types will help in further refining treatment regimens for patients and will decrease the chance of relapse caused by Gc-resistant cancer phenotypes.
Flexural capacity of one-way GFRP concrete slabs
Authors: Lotfy Ehab M. , Elzeiny Sherif M. , Rashad Alaa M.
Published: May 2011

The objective of the reported study was to investigate and evaluate the behaviour of one-way concrete slabs reinforced with glass-fibre-reinforced polymer (GFRP) rebars under distributed and line loads. A fibre-reinforced polymer (FRP) composite made with resin-impregnated continuous fibres is considered a promising alternative to traditional steel reinforcement. The experimental programme used eight GFRP concrete slabs to study the type of rebar (steel and GFRP), strength of concrete (25 and 45 MPa), reinforcement ratio and type of loading (distributed and line) loads. The results from a series of tests showed that strains of GFRP rebars are generally larger than those of steel rebars, increasing the ratios of the GFRP rebars led to an increase in ultimate flexural strength and increasing the concrete strength of the slabs led to an increase in slab rigidity, which improves flexural capacity. Furthermore, it was found that failure of slabs reinforced with GFRP rebars occurred by crushing and end slip of GFRP rebars must be prevented by using additional bars beyond the supports.
Aggregate selection for durability of concrete structures
Authors: Shayan Ahmad
Published: May 2011

Aggregate is a major component of concrete and its properties therefore have a significant influence on the behaviour of concrete made with it. Many countries have developed their own suite of tests to enable assessment of aggregates for concrete. The Australian standard tests included in the AS1141 group of aggregate tests cover most of the issues relevant to the performance of aggregate in concrete. However, there are two important properties for which standard test methods have either not been developed, or are still evolving. The situation in some other countries could be similar. First, there is a need to test the dimensional stability of the aggregate in response to changes in moisture content, which is related to the weathering/alteration stage of the rock and its clay content (physical stability). Second, there is a need to predict correctly the susceptibility of aggregates to deleterious alkali–aggregate reaction (AAR) in concrete (chemical stability). Both forms of dimensional instability of the aggregate can cause cracking of the concrete that incorporates it. This paper, rather than presenting new experimental data, draws on knowledge gained from previous work by the author in Australia, and by others elsewhere, and proposes the adoption of appropriate test methods for dealing with these issues. Reference is also been made to corresponding practices overseas with respect to these two aspects of aggregate selection.
Production of HSC using pumicite and water-reducing admixture
Authors: Dawood Eethar Thanon , Ramli Mahyuddin , Ismaeel Nadia S.
Published: May 2011

Currently high-strength concrete is increasingly used in modern concrete technology and particularly in the construction of high-rise buildings. This study has been conducted to investigate the properties of high-strength concrete that was produced by using a superplasticiser high-range water-reducing admixture (HRWRA) and pumicite. The results show that the use of admixtures (HRWRA with and without pumicite) led to the production of high-strength concrete and this was due to a water reduction of 21.6–25% produced by using HRWRA and 7% of pumicite as a partial replacement of cement. The properties of compressive strength, splitting tensile strength, flexural strength, static modulus of elasticity, absorption and air-dry density were tested in this study. It can be concluded that all the aforementioned properties were enhanced by the use of superplasticiser and pumicite in the concrete mixes. Furthermore, the use of 6 kg/m3 of superplasticiser (Melment L10) with 29 kg/m3 of pumicite made it possible to reduce the cement content by about 164 kg/m3 without any reduction in compressive strength.
The right to water and its relevance to sustainable water governance
Authors: Grimes Hilary J.
Published: May 2011

Over the past decade, the focus of water sector improvements in developing countries has moved away from enhancing physical infrastructure towards strengthening water sector governance. However, good water governance is a mechanism for improvement, not an end in itself, and the ultimate goal of governance reforms is still rarely defined clearly. One notable exception is the water reform process in South Africa; the right of access to water services is enshrined in South Africa's constitution and defined in subsequent legislation. Unfortunately, the implementation of reforms has been less straightforward and has recently brought water service providers into conflict with consumers who consider their right to water is being violated. This paper demonstrates the utility of the United Nations (UN) general comment No. 15 on the ‘right to water’ in assisting those responsible for the planning and implementation of sustainable water sector governance reforms. The key aspects of the right to water are explained and a number of myths refuted. The paper discusses some of the problems encountered by water services institutions in South Africa and how these could have been avoided had more attention been given to the principles embodied in the UN general comment.
On governance for re-engineering city infrastructure
Authors: Beck M. Bruce , Thompson Michael , Ney Steven , Gyawali Dipak , Jeffrey Paul
Published: May 2011

Given the challenge of re-engineering the infrastructure of a city so that it may become a force for good in the environment, what structure of governance might promote/stifle any associated technological and technical innovations? How might the ‘quality’ of the sought-for governance be gauged and improved? Cultural theory is introduced to address these questions and briefly elaborated. In particular, it is shown how cultural theory can be used to refurbish Dahl's theory of pluralist democracy and provide a simple (and visual) metric of deliberative quality in governance. Matters of re-engineering the water-nutrient infrastructures of the city of Atlanta within the Chattahoochee watershed in the southeastern USA provide the primary setting for eventually applying the resulting conceptual framework. Drawing together a somewhat eclectic mix of past experience and prospective approaches – ranging from practical resolutions of water conflicts in Nepal, lessons learned from previous community engagement in the Atlanta–Chattahoochee system, and two stagings of the sustainability agora of the International Water Association – a cultural theory-inspired programme of work is developed to explore and assemble those elements of governance that should, in practice, enable the re-engineering needed for a city to become a force for good in its environment.
Metabolic Remodeling of Human Skeletal Myocytes by Cocultured Adipocytes Depends on the Lipolytic State of the System
Authors: Kovalik Jean-Paul , Slentz Dorothy , Stevens Robert D. , Kraus William E. , Houmard Joseph A. , Nicoll James B. , Lea-Currie Y. Renee , Everingham Karen , Kien C. Lawrence , Buehrer Benjamin M. , Muoio Deborah M.
Published: May 2011

OBJECTIVE

Adipocyte infiltration of the musculoskeletal system is well recognized as a hallmark of aging, obesity, and type 2 diabetes. Intermuscular adipocytes might serve as a benign storage site for surplus lipid or play a role in disrupting energy homeostasis as a result of dysregulated lipolysis or secretion of proinflammatory cytokines. This investigation sought to understand the net impact of local adipocytes on skeletal myocyte metabolism.

RESEARCH DESIGN AND METHODS

Interactions between these two tissues were modeled using a coculture system composed of primary human adipocytes and human skeletal myotubes derived from lean or obese donors. Metabolic analysis of myocytes was performed after coculture with lipolytically silent or activated adipocytes and included transcript and metabolite profiling along with assessment of substrate selection and insulin action.

RESULTS

Cocultured adipocytes increased myotube mRNA expression of genes involved in oxidative metabolism, regardless of the donor and degree of lipolytic activity. Adipocytes in the basal state sequestered free fatty acids, thereby forcing neighboring myotubes to rely more heavily on glucose fuel. Under this condition, insulin action was enhanced in myotubes from lean but not obese donors. In contrast, when exposed to lipolytically active adipocytes, cocultured myotubes shifted substrate use in favor of fatty acids, which was accompanied by intracellular accumulation of triacylglycerol and even-chain acylcarnitines, decreased glucose oxidation, and modest attenuation of insulin signaling.

CONCLUSIONS

The effects of cocultured adipocytes on myocyte substrate selection and insulin action depended on the metabolic state of the system. These findings are relevant to understanding the metabolic consequences of intermuscular adipogenesis.
Comparison of Dorsocervical With Abdominal Subcutaneous Adipose Tissue in Patients With and Without Antiretroviral Therapy–Associated Lipodystrophy
Authors: Sevastianova Ksenia , Sutinen Jussi , Greco Dario , Sievers Meline , Salmenkivi Kaisa , Perttilä Julia , Olkkonen Vesa M. , Wågsäter Dick , Lidell Martin E. , Enerbäck Sven , Eriksson Per , Walker Ulrich A. , Auvinen Petri , Ristola Matti , Yki-Järvinen Hannele
Published: May 2011

OBJECTIVE

Combination antiretroviral therapy (cART) is associated with lipodystrophy, i.e., loss of subcutaneous adipose tissue in the abdomen, limbs, and face and its accumulation intra-abdominally. No fat is lost dorsocervically and it can even accumulate in this region (buffalo hump). It is unknown how preserved dorsocervical fat differs from abdominal subcutaneous fat in HIV-1–infected cART-treated patients with (cART+LD+) and without (cART+LD−) lipodystrophy.

RESEARCH DESIGN AND METHODS

We used histology, microarray, PCR, and magnetic resonance imaging to compare dorsocervical and abdominal subcutaneous adipose tissue in cART+LD+ (n = 21) and cART+LD− (n = 11).

RESULTS

Albeit dorsocervical adipose tissue in cART+LD+ seems spared from lipoatrophy, its mitochondrial DNA (mtDNA; copies/cell) content was significantly lower (by 62%) than that of the corresponding tissue in cART+LD−. Expression of CD68 mRNA, a marker of macrophages, and numerous inflammatory genes in microarray were significantly lower in dorsocervical versus abdominal subcutaneous adipose tissue. Genes with the greatest difference in expression between the two depots were those involved in regulation of transcription and regionalization (homeobox genes), irrespective of lipodystrophy status. There was negligible mRNA expression of uncoupling protein 1, a gene characteristic of brown adipose tissue, in either depot.

CONCLUSIONS

Because mtDNA is depleted even in the nonatrophic dorsocervical adipose tissue, it is unlikely that the cause of lipoatrophy is loss of mtDNA. Dorsocervical adipose tissue is less inflamed than lipoatrophic adipose tissue. It does not resemble brown adipose tissue. The greatest difference in gene expression between dorsocervical and abdominal subcutaneous adipose tissue is in expression of homeobox genes.
Metformin and Exercise in Type 2 Diabetes
Authors: Boulé Normand G. , Robert Cheri , Bell Gordon J. , Johnson Steven T. , Bell Rhonda C. , Lewanczuk Richard Z. , Gabr Raniah Q. , Brocks Dion R.
Published: May 2011

OBJECTIVE

To determine the effect of metformin on the acute metabolic response to submaximal exercise, the effect of exercise on plasma metformin concentrations, and the interaction between metformin and exercise on the subsequent response to a standardized meal.

RESEARCH DESIGN AND METHODS

Ten participants with type 2 diabetes were recruited for this randomized crossover study. Metformin or placebo was given for 28 days, followed by the alternate condition for 28 days. On the last 2 days of each condition, participants were assessed during a nonexercise and a subsequent exercise day. Exercise took place in the morning and involved a total of 35 min performed at three different submaximal intensities.

RESULTS

Metformin increased heart rate and plasma lactate during exercise (both P ≤ 0.01) but lowered respiratory exchange ratio (P = 0.03) without affecting total energy expenditure, which suggests increased fat oxidation. Metformin plasma concentrations were greater at several, but not all, time points on the exercise day compared with the nonexercise day. The glycemic response to a standardized meal was reduced by metformin, but the reduction was attenuated when exercise was added (metformin × exercise interaction, P = 0.05). Glucagon levels were highest in the combined exercise and metformin condition.

CONCLUSIONS

This study reveals several ways by which metformin and exercise therapies can affect each other. By increasing heart rate, metformin could lead to the prescription of lower exercise workloads. Furthermore, under the tested conditions, exercise interfered with the glucose-lowering effect of metformin.
Glucose Absorption in Gestational Diabetes Mellitus During an Oral Glucose Tolerance Test
Authors: Anderwald Christian , Tura Andrea , Winhofer Yvonne , Krebs Michael , Winzer Christine , Bischof Martin G. , Luger Anton , Pacini Giovanni , Kautzky-Willer Alexandra
Published: May 2011

OBJECTIVE

Women with gestational diabetes mellitus (GDM) show reduced insulin sensitivity and markedly elevated glucose excursions. After delivery, GDM mostly reverts to normal glucose tolerance (NGT), although leaving an increased risk of type 2 diabetes. Because gastrointestinal function changes during pregnancy causing vomiting, constipation, or reduced motility, we thought that gut glucose absorption in GDM or pregnancy might be altered to affect circulating glucose excursions.

RESEARCH DESIGN AND METHODS

By undergoing 180-min oral glucose tolerance tests (OGTTs), pregnant women with GDM (GDMpreg; n = 15, BMI = 32 ± 2 kg/m2, aged 33 ± 1 years) were compared with NGT women (NGTpreg; n = 7, BMI = 28 ± 1 kg/m2, aged 34 ± 2 years), matching for major anthropometric characteristics (each P > 0.2). After delivery (6–7 months later), both groups were studied the same way. We computed and mathematically modeled gut glucose absorption from insulin-mediated glucose disappearance and endogenous glucose production (EGP). Whole-body insulin sensitivity was calculated using the Clamp-like Index.

RESULTS

GDMpreg showed 16–25% higher plasma glucose concentrations (P < 0.04) during the final 2 h of OGTT, similar EGP, but lower (P < 0.01) insulin sensitivity (2.7 ± 0.2 mg · kg−1 · min−1 vs. NGTpreg: 4.5 ± 0.8 mg · kg−1 · min−1). In GDMpreg, gut glucose absorption rates were ≤52% lower from 30 to 120 min (P < 0.03 vs. conditions after delivery or NGTpreg). In contrast, glucose absorption rates in NGTpreg were comparable during and after pregnancy. None of the studied women developed diabetes after delivery.

CONCLUSIONS

In GDMpreg, OGTT gut glucose absorption is markedly lower during hyperglycemia, whereas both glycemia and glucose absorption in NGTpreg are comparable between pregnant and postpartum states. Thus, hyperglycemia in GDM does not seem to result from too rapid or increased glucose absorption.