bluuebunny/crossref_metadata_2025 huggingface dataset:
Intra-arterial Thrombolysis of Acute Iatrogenic Intracranial Arterial Occlusion Attributable to Neuroendovascular Procedures or Coronary Angiography
Authors: Arnold Marcel , Fischer Urs , Schroth Gerhard , Nedeltchev Krassen , Isenegger Joerg , Remonda Luca , Windecker Stephan , Brekenfeld Caspar , Mattle Heinrich P.
Published: March 2008

Background and Purpose—

For selected stroke patients, intra-arterial thrombolysis (IAT) has been shown to be an effective treatment option. However, knowledge of safety and efficacy of IAT in patients with acute stroke as a complication of arterial catheter interventions is limited.

Methods—

We analyzed clinical radiological findings and functional outcomes in consecutive patients 3 months after treatment with IAT for peri-procedural strokes occurring during neuroendovascular or cardiac catheter interventions. To measure outcome, the modified Rankin scale score was used.

Results—

Of a total of 432 patients treated with IAT, 12 (4 women and 8 men; mean age, 60 years) were treated because of an ischemic stroke after a neuro-endovascular procedure (n=6) or coronary angiography (n=6). The median baseline National Institutes of Health Stroke Scale score was15. Recanalization was complete (thrombolysis in myocardial infarction grade 3) in 6, partial (thrombolysis in myocardial infarction 2) in 5, and minimal (thrombolysis in myocardial infarction 1) in 1. Nine patients (75%) had a favorable outcome (modified Rankin scale score, 0 to 2), and 3 had a poor outcome (modified Rankin scale score, 3 or 4). All patients with complete recanalization had a favorable outcome, whereas only 3 of 6 patients with partial or minimal recanalization (
P
=0.18) had a favorable outcome. Follow-up brain imaging was normal in 2 and showed new ischemic lesions in 10 patients. Two patients (17%) had a symptomatic intracerebral hemorrhage.

Conclusion—

In acute stroke attributable to arterial catheter interventions, IAT is feasible and has the potential to improve outcome in these patients. A high recanalization rate could be achieved.
Genetic Variation of the Androgen Receptor and Risk of Myocardial Infarction and Ischemic Stroke in Women
Authors: Rexrode Kathryn M. , Ridker Paul M. , Hegener Hillary H. , Buring Julie E. , Manson JoAnn E. , Zee Robert Y.L.
Published: March 2008

Background and Purpose—

Androgen receptors (AR) are expressed in endothelial cells and vascular smooth-muscle cells. Some studies suggest an association between AR gene variation and risk of cardiovascular disease (CVD) in men; however, the relationship has not been examined in women.

Methods—

Six haplotype block-tagging single nucleotide polymorphisms (rs962458, rs6152, rs1204038, rs2361634, rs1337080, rs1337082), as well as the cysteine, adenine, guanine (CAG) microsatellite in exon 1, of the AR gene were evaluated among 300 white postmenopausal women who developed CVD (158 myocardial infarctions and 142 ischemic strokes) and an equal number of matched controls within the Women’s Health Study.

Results—

Genotype distributions were similar between cases and controls, and genotypes were not significantly related to risk of CVD, myocardial infarctions or ischemic stroke in conditional logistic regression models. Seven common haplotypes were observed, but distributions did not differ between cases and controls nor were significant associations observed in logistic regression analysis. The median CAG repeat length was 21. In conditional logistic regression, there was no association between the number of alleles with CAG repeat length ≥21 (or ≥22) and risk of CVD, myocardial infarctions or ischemic stroke.

Conclusions—

No association between AR genetic variation, as measured by haplotype-tagging single nucleotide polymorphisms and CAG repeat number, and risk of CVD was observed in women.
Feature Forest Models for Probabilistic HPSG Parsing
Authors: Miyao Yusuke , Tsujii Jun'ichi
Published: March 2008

Probabilistic modeling of lexicalized grammars is difficult because these grammars exploit complicated data structures, such as typed feature structures. This prevents us from applying common methods of probabilistic modeling in which a complete structure is divided into sub-structures under the assumption of statistical independence among sub-structures. For example, part-of-speech tagging of a sentence is decomposed into tagging of each word, and CFG parsing is split into applications of CFG rules. These methods have relied on the structure of the target problem, namely lattices or trees, and cannot be applied to graph structures including typed feature structures.

This article proposes the feature forest model as a solution to the problem of probabilistic modeling of complex data structures including typed feature structures. The feature forest model provides a method for probabilistic modeling without the independence assumption when probabilistic events are represented with feature forests. Feature forests are generic data structures that represent ambiguous trees in a packed forest structure. Feature forest models are maximum entropy models defined over feature forests. A dynamic programming algorithm is proposed for maximum entropy estimation without unpacking feature forests. Thus probabilistic modeling of any data structures is possible when they are represented by feature forests.

This article also describes methods for representing HPSG syntactic structures and predicate-argument structures with feature forests. Hence, we describe a complete strategy for developing probabilistic models for HPSG parsing. The effectiveness of the proposed methods is empirically evaluated through parsing experiments on the Penn Treebank, and the promise of applicability to parsing of real-world sentences is discussed.
Differing Estimates of Observed Bangladesh Summer Rainfall
Authors: Cash Benjamin A. , Rodó Xavier , Kinter James L. , Fennessy Michael J. , Doty Brian
Published: March 2008

The differences in boreal summer (June–August) monthly-mean rainfall estimates over the Indian Ocean region in five research-quality products are examined for the period 1979–2003. Two products derived from the merged satellite and surface observations are considered: the Climate Prediction Center (CPC) Merged Analysis of Precipitation (CMAP) and the Global Precipitation Climatology Project (GPCP). In addition, three products derived solely from rain gauge observations are considered: the Chen et al. product; the Indian Meteorological Department (IMD) product; and a new, objectively analyzed product based on the Climate Anomaly Monitoring System (CAMS) dataset.

Significant discrepancies have been found between the different products across the entire Indian Ocean region, with the greatest disagreement over Burma and neighboring Bangladesh. These differences appear to be primarily due to the absence of reported rain gauge data for Burma and differences in the algorithms used to merge the satellite microwave emission and scattering data in coastal regions. Representations of rainfall across much of the eastern Indian Ocean region would likely be improved by the identification and inclusion of reporting stations from Burma and a refinement of the techniques used for merging microwave data. The differences among the five products are sufficient to affect both quantitative and qualitative conclusions drawn about rainfall, particularly over Bangladesh and Burma. Consequently, the results of precipitation studies in this region will depend, in some cases, on the choice of the data product, including such basic questions as to whether a given summer was wet or dry. Of particular note is that the apparent relationship between rainfall and ENSO can depend on the choice of the data product.
Impact of TMI SST on the Simulation of a Heavy Rainfall Episode over Mumbai on 26 July 2005
Authors: Deb S. K. , Kishtawal C. M. , Pal P. K. , Joshi P. C.
Published: March 2008

In this study the simulation of a severe rainfall episode over Mumbai on 26 July 2005 has been attempted with two different mesoscale models. The numerical models used in this study are the Brazilian Regional Atmospheric Modeling System (BRAMS) developed originally by Colorado State University and the Advanced Research Weather Research Forecast (WRF-ARW) Model, version 2.0.1, developed at the National Center for Atmospheric Research. The simulations carried out in this study use the Grell–Devenyi Ensemble cumulus parameterization scheme. Apart from using climatological sea surface temperature (SST) for the control simulations, the impact of the Tropical Rainfall Measuring Mission (TRMM) Microwave Imager (TMI) SST on the simulation of rainfall is evaluated using these two models. The performances of the models are compared by examining the predicted parameters like upper- and lower-level circulations, moisture, temperature, and rainfall. The strength of convective instability is also derived by calculating the convective available potential energy. The intensity of maximum rainfall around Mumbai is significantly improved with TMI SST as the surface boundary condition in both the models. The large-scale circulation features, moisture, and temperature are compared with those in the National Centers for Environmental Prediction analyses. The rainfall prediction is assessed quantitatively by comparing the simulated rainfall with the rainfall from TRMM products and the observed station values reported in Indian Daily Weather Reports from the India Meteorological Department.
The Swedish labour market in the 1990s: The very last of the healthy jobs?
Authors: Rostila Mikael
Published: March 2008

Background: The economic recession in Sweden in the 1990s influenced several aspects of the labour market, including the psychosocial work environment. This study examined psychosocial working conditions in relation to self-reported ill-health in the 1990s by means of the job strain model. Methods: The study was based on two representative cross-sectional samples of Swedish employed men and women in 1991 (n=3,292) and 2000 (n=3,010), together with a panel of employees who were included for both years (n=1,953). The main outcome measures were psychological distress and self-rated poor health. The primary method used was logistic regression. Results: The results suggested that although adverse psychosocial conditions increased during the 1990s, the association with health weakened. However, further analyses showed that poor health increased in most groups with various types of psychosocial conditions, and that reduced relative differences in poor health were discernible. Finally, a longitudinal analysis showed that long-term exposure to and experience of deteriorating psychosocial conditions was most detrimental for health at the end of the 1990s, once health status at baseline had been adjusted for. Conclusions: The increased prevalence of health problems among most groups with various psychosocial conditions during the 1990s, together with reduced relative differences in poor health, might make it more difficult for employers and policy-makers to direct health policies towards specific groups of employees, as the "healthy'' job seems to have disappeared. Another important inference of the results is that psychosocial working conditions seem to be causally related to health.
Psychological distress among Kurdish immigrants in Sweden
Authors: Taloyan Marina , Johansson Sven-Erik , Sundquist Jan , Koctürk Tahire O. , Johansson Leena Maria
Published: March 2008

Aims: To analyse whether there is an association between sex and poor self-reported health (SRH) and psychological distress in Kurdish immigrants. Methods: This cross-sectional study is based on a sample consisting of immigrants, aged 27— 60 years, with self-reported Kurdish ethnicity (n=111, men; n=86, women) in Sweden originating from Iran and Turkey. It is based on data collected in 1996 from the first Swedish National Survey on the living conditions of immigrant groups conducted by Statistics Sweden. The prevalences of reporting poor health, sleeping difficulties, general fatigue and anxiety were estimated by sex. The association between sex and SRH and psychological distress was analysed by an unconditional logistic regression model estimating odds ratios (OR) with 95% confidence intervals. The final model was adjusted for age, marital status, education, housing and employment. Immigrant-specific migration-related variables were used to explore possible reasons for the sex differences. Results: Kurdish men and women had a high prevalence of poor SRH and psychological distress. Age-adjusted odds ratios for anxiety were higher in Kurdish women. Sex differences in anxiety remained even when marital status, education, housing and employment were taken into account. Conclusions: Kurdish men and women report a high prevalence of poor SRH and indicators of psychological distress. Women had a higher risk for anxiety than men. Negative experiences of pre-migration as well as post-migration experiences, such as economic difficulties, preoccupation with the political situation in the home country, perceived discrimination, and feelings of poor control over one's life, were associated with the outcomes.
Clinical problems at the end of life in a Swedish population, including the role of advancing age and physical and cognitive function
Authors: Jakobsson Eva , Gaston-Johansson Fannie , Öhlén Joakim , Bergh Ingrid
Published: March 2008

Aims: To improve the understanding of specific clinical problems at the end of life, including the role of advancing age, physical function and cognitive function. Methods: The study is part of an explorative survey of data relevant to end-of-life healthcare services during the last 3 months of life of a randomly selected sample of the population of a Swedish county. Data were selected through retrospective reviews of death certificates and medical records, and comprise information from 12 municipalities and 229 individuals. Results: A range of prevalent concerns was found. Overall deterioration, urinary incontinence, constipation, impaired skin integrity, anxiety and sleep disturbances were significantly associated with dependency on others for activities of daily living; pulmonary rattles and swallowing disturbances were associated with cognitive disorientation; excepting cough, advancing age did not have significant impacts on these prevalent clinical concerns. Conclusions: A range of distressing conditions constitute a common pathway for many individuals at or near the end of life. The incorporation of health promotion as a principle of palliative care will probably benefit individuals at the end of life, and includes a proactive focus and emphasis on enhanced well-being at the time of diagnosis of a life-threatening illness. For individuals with physical and cognitive limitations imparting a state of dependency, it is reasonable to provide assurance of care for individuals' specific needs by professionals with both training for and competence in this special and sometimes unique clinical environment.
Screening for postpartum depression with the Edinburgh Postnatal Depression Scale (EPDS): An ethical analysis
Authors: Krantz Ingela , Eriksson Bo , Lundquist-Persson Cristina , Ahlberg Beth Maina , Nilstun Tore
Published: March 2008

Aims: To assess the Edinburgh Postnatal Depression Scale (EPDS), a self-administered questionnaire created to screen for symptoms of postpartum depression in the community, from an epidemiological and ethical perspective. Screening, as the practice of investigating apparently healthy individuals to detect unrecognised disease or its precursors, has interpretation problems and is complicated by deliberations on probabilities for something to occur, on which the scientific community is unanimous. Methods: Our ethical analysis is made using a framework with two different dimensions, the ethical principles autonomy and beneficence and the affected persons. To balance the ethical costs and the ethical benefits of EPDS an analogy with the assessment of pharmaceutics is used. Results: In this article we argue that routine EPDS screening of Swedish postpartum women would lead to considerable ethical problems due to the weak scientific foundation of the screening instrument. Despite a multitude of published studies, the side-effects in terms of misclassifications have not been considered carefully. The EPDS does not function very well as a routine screening instrument. The dualism created is too reductive and fails to recognize the plurality of difference that exists in the social word. Conclusions: Public health authorities should not advocate screening of unproved value. Screening is not just a medical issue but also an ethical one.
Implementing the Youth 'Anti-social Behaviour' Agenda: Policing the Ashton Estate
Authors: Sadler Joanna
Published: March 2008

The article presents findings of a doctoral research project that examined the implementation of legislation targeted at youth `anti-social behaviour', which began with the Crime and Disorder Act 1998 (Sadler, 2004). A 2-year ethnographic case study examined the implementation of the legislation on an inner city housing estate in England, and the broader effects of the contemporary `youth “anti-social behaviour” agenda' on local policing. Pseudonyms have been used throughout the article to preserve the anonymity of people and places. The research found that increasing knowledge about the legislation among local services involved in community safety, intensified the ways in which young people congregating in the estate's public spaces were problematized and policed. In turn, this began to exacerbate already fragile police—youth relationships and encouraged feelings of stigmatization and social exclusion among local young people.
Using Drama to Prevent Teen Smoking: Development, Implementation, and Evaluation of Crossroads in Hawai`i
Authors: Mitschke Diane B. , Loebl Karen , Tatafu Elitei , Segal Matsunaga Doris , Cassel Kevin
Published: March 2008

The use of drama as a preventive education measure has demonstrated success in various health promotion venues and offers promise in promoting positive youth attitudes and behavior change related to tobacco use. Especially important is a need to implement culturally relevant methods to reach youth. This article describes the development and implementation of a tobacco prevention drama for Asian and Pacific Islander youth. The resulting play, Crossroads , features a soap opera-style drama interspersed with humorous vignettes and multimedia effects and incorporates cultural cues, mannerisms, dress, and values consistent with Asian and Pacific Islander youth culture. Evaluation data indicate that the drama has an effect on audience knowledge, attitudes, and intended behavior, including a change in future intent to smoke cigarettes and the ability of audience members to develop connections with the characters in the play and apply concepts that are presented in the play to their own lives.
Endogenous galectin-1 enforces class I–restricted TCR functional fate decisions in thymocytes
Authors: Liu Scot D. , Whiting Chan C. , Tomassian Tamar , Pang Mabel , Bissel Stephanie J. , Baum Linda G. , Mossine Valeri V. , Poirier Françoise , Huflejt Margaret E. , Miceli M. Carrie
Published: March 2008

During thymocyte development, the T-cell receptor (TCR) can discriminate major histocompatibility complex (MHC)/peptide ligands over a narrow range of affinities and translate subtle differences into functional fate decisions. How small differences in TCR input are translated into absolute differences in functional output is unclear. We examined the effects of galectin-1 ablation in the context of class-I–restricted thymocyte development. Galectin-1 expression opposed TCR partial agonist-driven positive selection, but promoted TCR agonist-driven negative selection of conventional CD8+ T cells. Galectin-1 expression also promoted TCR agonist-driven CD8αα intestinal intraepithelial lymphocytes (IEL) development. Recombinant galectin-1 enhanced TCR binding to agonist/MHC complexes and promoted a negative-selection-signaling signature, reflected in intensified rapid and transient extracellular signal-regulated kinase (ERK) activation. In contrast, galectin-1 expression antagonized ERK activity in thymocytes undergoing positive selection. We propose that galectin-1 aids in discriminating TCR-directed fate decisions by promoting TCR binding to agonist/MHC complexes and enforcing agonist-driven signals, while opposing partial-agonist signals. In this way, galectin-1 widens the distinction between TCR-directed functional fate cues.
Correlates of HIV, HBV, HCV and syphilis infections among prison inmates and officers in Ghana: A national multicenter study
Authors: Adjei Andrew A , Armah Henry B , Gbagbo Foster , Ampofo William K , Boamah Isaac , Adu-Gyamfi Clement , Asare Isaac , Hesse Ian FA , Mensah George
Published: March 2008

Background

Prisons are known to be high-risk environments for the spread of bloodborne and sexually transmitted infections. Prison officers are considered to have an intermittent exposure potential to bloodborne infectious diseases on the job, however there has been no studies on the prevalence of these infections in prison officers in Ghana.

Methods

A national multicenter cross-sectional study was undertaken on correlates of human immunodeficiency virus (HIV), hepatitis B virus (HBV), hepatitis C virus (HCV), and syphilis infections in sample of prison inmates and officers from eight of ten regional central prisons in Ghana. A total of 1366 inmates and 445 officers were enrolled between May 2004 and December 2005. Subjects completed personal risk-factor questionnaire and provided blood specimens for unlinked anonymous testing for presence of antibodies to HIV, HCV andTreponema pallidum; and surface antigen of HBV (HBsAg). These data were analyzed using both univariate and multivariate techniques.

Results

Almost 18% (1336) of 7652 eligible inmates and 21% (445) of 2139 eligible officers in eight study prisons took part. Median ages of inmates and officers were 36.5 years (range 16–84) and 38.1 years (range 25–59), respectively. Among inmates, HIV seroprevalence was 5.9%, syphilis seroprevalence was 16.5%, and 25.5% had HBsAg. Among officers tested, HIV seroprevalence was 4.9%, HCV seroprevalence was 18.7%, syphilis seroprevalence was 7.9%, and 11.7% had HBsAg. Independent determinants for HIV, HBV and syphilis infections among inmates were age between 17–46, being unmarried, being illiterate, female gender, being incarcerated for longer than median time served of 36 months, history of homosexuality, history of intravenous drug use, history of sharing syringes and drug paraphernalia, history of participation in paid sexual activity, and history of sexually transmitted diseases. Independent determinants for HIV, HBV, HCV and syphilis infections among officers were age between 25–46, fale gender, being unmarried, being employed in prison service for longer than median duration of employment of 10 years, and history of sexually transmitted diseases.

Conclusion

The comparably higher prevalence of HIV, HBV, HCV and syphilis in prison inmates and officers in Ghana suggests probable occupational related transmission. The implementation of infection control practices and risk reduction programs targeted at prison inmates and officers in Ghana is urgently required to address this substantial exposure risk.
A variant form of acute reversible cardiomyopathy: a case report
Authors: Karavidas Apostolos , Arapi Sofia , Fotiadis John , Zacharoulis Achilleas , Matsakas Evagellos
Published: March 2008

Introduction

Stress cardiomyopathy, also known as Takotsubo cardiomyopathy or left ventricular apical ballooning, has been linked to emotional or physical stress resulting in transient left ventricular dysfunction. It typically affects the mid and apical left ventricular segments. At onset, it resembles acute myocardial infarction, due to the acute onset of chest pain and ST-T segment elevation. However, there is minimal biomarker elevation and a normal coronary artery angiogram.

Case presentation

We report a case of a woman with transient myocardial injury after a stressful event, presenting with a variation of the affected segments. In this case, only the basal and mid portions of the left ventricle were affected, while the apex was completely spared. Coronary angiography revealed no significant occlusion and left ventricular function had recovered completely by the third day of hospitalization.

Conclusion

We present a variant form of stress cardiomyopathy, affecting the basal and mid segments of the left ventricle.
Differential Regulation of Prostaglandin Production Mediated by Corticotropin-Releasing Hormone Receptor Type 1 and Type 2 in Cultured Human Placental Trophoblasts
Authors: Gao Lu , Lu Chunmei , Xu Chen , Tao Yi , Cong Binhai , Ni Xin
Published: March 2008

Prostaglandin (PG) production by intrauterine tissues plays a key part in the control of pregnancy and parturition. The present study was to investigate the role of placenta-derived CRH and CRH-related peptides in the regulation of PG synthesis and metabolism. We found that placental trophoblasts expressed both CRH-R1 and CRH-R2. Treatment of cultured placental cells with either a CRH or urocortin I (UCNI) antibody resulted in a significant decrease in PGE2 release. Both CRH and UCNI antibodies significantly decreased mRNA and protein expression of synthetic enzymes cytosolic phospholipase A2 (cPLA2) and cyclooxygenase (COX)-2 and increased mRNA and protein expression of 15-hydroxyprostaglandin dehydrogenase (PGDH), the key enzyme of PG metabolism. CRH-R1/-R2 antagonist astressin and CRH-R1 antagonist antalarmin significantly inhibited PGE2 release, whereas CRH-R2 antagonist astressin-2b had no effect on PGE2 release. Administration of astressin decreased expression of cPLA2 but had no effect on COX-2 expression. Antalarmin reduced cPLA2 and COX-2 expression, whereas astressin-2b did not alter cPLA2 expression but increased COX-2 expression. PGDH expression was enhanced by these three antagonists. Cells treated with exogenous CRH and UCNI showed an increase in PGE2 release and expression of cPLA2 and COX-2 but a decrease in PGDH expression. UCNII and UCNIII had no effect on PGE2 release but decreased COX-2 and PGDH expression. Our results suggested CRH and CRH-related peptides act on CRH-R1 and CRH-R2 to exert different effects on PG biosynthetic enzymes cPLA2 and COX-2 and thereby modulate output of PGs from placenta, which would be important for controlling pregnancy and parturition.
Adaptation to Mild, Intermittent Stress Delays Development of Hyperglycemia in the Zucker Diabetic Fatty Rat Independent of Food Intake: Role of Habituation of the Hypothalamic-Pituitary-Adrenal Axis
Authors: Bates Holly E. , Sirek Adam S. , Kiràly Michael A. , Yue Jessica T. Y. , Goche Montes Danitza , Matthews Stephen G. , Vranic Mladen
Published: March 2008

Hypothalamic-pituitary-adrenal (HPA) axis hyperactivity occurs in type 2 diabetes, and stress is assumed to play a causal role. However, intermittent restraint stress, a model mimicking some mild stressors, delays development of hyperglycemia in Zucker diabetic fatty (ZDF) rats. We examine whether such stress delays hyperglycemia independent of stress-induced reductions in hyperphagia and is due to adaptations in gene expression of HPA-related peptides and receptors that ameliorate corticosteronemia and thus hyperglycemia. ZDF rats were intermittently restraint stressed (1 h/d, 5 d/wk) for 13 wk and compared with obese control, pair fed, and lean ZDF rats. After 13 wk, basal hormones were repeatedly measured over 24 h, and HPA-related gene expression was assessed by in situ hybridization. Although restraint initially induced hyperglycemia, this response habituated over time, and intermittent restraint delayed hyperglycemia. This delay was partly related to 5–15% decreased hyperphagia, which was not accompanied by decreased arcuate nucleus NPY or increased POMC mRNA expression, although expression was altered by obesity. Obese rats demonstrated basal hypercorticosteronemia and greater corticosterone responses to food/water removal. Basal hypercorticosteronemia was further exacerbated after 13 wk of pair feeding during the nadir. Importantly, intermittent restraint further delayed hyperglycemia independent of food intake, because glycemia was 30–40% lower than after 13 wk of pair feeding. This may be mediated by increased hippocampal MR mRNA, reduced anterior pituitary POMC mRNA levels, and lower adrenal sensitivity to ACTH, thus preventing basal and stress-induced hypercorticosteronemia. In contrast, 24-h catecholamines were unaltered. Thus, rather than playing a causal role, intermittent stress delayed deteriorations in glycemia and ameliorated HPA hyperactivity in the ZDF rat.
Functional Characterization of Genetically Labeled Gonadotropes
Authors: Wen Shuping , Schwarz Jürgen R. , Niculescu Dragos , Dinu Crenguta , Bauer Christiane K. , Hirdes Wiebke , Boehm Ulrich
Published: March 2008

Gonadotropes are crucial in the control of reproduction but difficult to isolate for functional analysis due to their scattered distribution in the anterior pituitary gland. We devised a binary genetic approach, and describe a new mouse model that allows visualization and manipulation of gonadotrope cells. Using gene targeting in embryonic stem cells, we generated mice in which Cre recombinase is coexpressed with the GnRH receptor, which is expressed in gonadotrope cells. We show that we can direct Cre-mediated recombination of a yellow fluorescent protein reporter allele specifically in gonadotropes within the anterior pituitary of these knock-in mice. More than 99% of gonadotropin-containing cells were labeled by yellow fluorescent protein fluorescence and readily identifiable in dissociated pituitary cell culture, allowing potentially unbiased sampling from the gonadotrope population. Using electrophysiology, calcium imaging, and the study of secretion on the single-cell level, the functional properties of gonadotropes isolated from male mice were analyzed. Our studies demonstrate a significant heterogeneity in the resting properties of gonadotropes and their responses to GnRH. About 50% of gonadotropes do not exhibit secretion of LH or FSH. Application of GnRH induced a broad range of both electrophysiological responses and increases in the intracellular calcium concentration. Our mouse model will also be able to direct expression of other Cre recombination-dependent reporter genes to gonadotropes and, therefore, represents a versatile new tool in the understanding of gonadotrope biology.
Active Intestinal Calcium Transport in the Absence of Transient Receptor Potential Vanilloid Type 6 and Calbindin-D9k
Authors: Benn Bryan S. , Ajibade Dare , Porta Angela , Dhawan Puneet , Hediger Matthias , Peng Ji-Bin , Jiang Yi , Oh Goo Taeg , Jeung Eui-Bae , Lieben Liesbet , Bouillon Roger , Carmeliet Geert , Christakos Sylvia
Published: March 2008

To study the role of the epithelial calcium channel transient receptor potential vanilloid type 6 (TRPV6) and the calcium-binding protein calbindin-D9k in intestinal calcium absorption, TRPV6 knockout (KO), calbindin-D9k KO, and TRPV6/calbindin-D9k double-KO (DKO) mice were generated. TRPV6 KO, calbindin-D9k KO, and TRPV6/calbindin-D9k DKO mice have serum calcium levels similar to those of wild-type (WT) mice (∼10 mg Ca2+/dl). In the TRPV6 KO and the DKO mice, however, there is a 1.8-fold increase in serum PTH levels (P < 0.05 compared with WT). Active intestinal calcium transport was measured using the everted gut sac method. Under low dietary calcium conditions there was a 4.1-, 2.9-, and 3.9-fold increase in calcium transport in the duodenum of WT, TRPV6 KO, and calbindin-D9k KO mice, respectively (n = 8–22 per group; P > 0.1, WT vs. calbindin-D9k KO, and P < 0.05, WT vs. TRPV6 KO on the low-calcium diet). Duodenal calcium transport was increased 2.1-fold in the TRPV6/calbindin-D9k DKO mice fed the low-calcium diet (P < 0.05, WT vs. DKO). Active calcium transport was not stimulated by low dietary calcium in the ileum of the WT or KO mice. 1,25-Dihydroxyvitamin D3 administration to vitamin D-deficient null mutant and WT mice also resulted in a significant increase in duodenal calcium transport (1.4- to 2.0-fold, P < 0.05 compared with vitamin D-deficient mice). This study provides evidence for the first time using null mutant mice that significant active intestinal calcium transport occurs in the absence of TRPV6 and calbindin-D9k, thus challenging the dogma that TRPV6 and calbindin-D9k are essential for vitamin D-induced active intestinal calcium transport.
Role for Inhibitor of Differentiation/Deoxyribonucleic Acid-Binding (Id) Proteins in Granulosa Cell Differentiation
Authors: Johnson A. L. , Haugen Morgan J. , Woods Dori C.
Published: March 2008

Recent studies in the hen ovary have linked the initiation of granulosa cell differentiation at follicle selection to the alleviation of inhibitory MAPK signaling. The present studies assessed a role for individual inhibitor of differentiation (Id) protein isoforms as modulators of key transcriptional events occurring within granulosa cells at or immediately subsequent to differentiation. Findings from freshly collected granulosa cells collected at different stages of follicle development demonstrated a negative association between expression levels for Id2 mRNA compared with levels of Id1, Id3, and Id4. Elevated levels of Id2 are related to a differentiating/differentiated phenotype, whereas elevated Id1, Id3, and Id4 are associated with an undifferentiated phenotype. This negative relationship extends to cell signal transduction, because factors that promote inhibitory MAPK signaling (TGF-α and betacellulin) block expression of Id2 mRNA but increase levels of Id1, Id3, and Id4. Furthermore, overexpression of Gallus Id2 in cultured granulosa was found to significantly decrease levels of Id1, Id3, and Id4 mRNA but facilitate FSHR mRNA expression and, importantly, initiate LHR mRNA expression plus LH-induced progesterone production. Finally, knockdown studies using small interfering RNA specific for Id2 revealed reduced expression of FSHR and LHR mRNA and attenuated FSH- and LH-induced levels of StAR and p450 cholesterol side-chain cleavage enzyme mRNA plus progesterone production. Collectively, these data demonstrate that Id2 expression is both sufficient and necessary for increasing LHR expression and, as a result, promoting gonadotropin-induced differentiation in hen granulosa cells subsequent to follicle selection.
Intracellular Proadrenomedullin-Derived Peptides Decorate the Microtubules and Contribute to Cytoskeleton Function
Authors: Sackett Dan L. , Ozbun Laurent , Zudaire Enrique , Wessner Lisa , Chirgwin John M. , Cuttitta Frank , Martínez Alfredo
Published: March 2008

Adrenomedullin (AM) and proadrenomedullin N-terminal 20 peptide (PAMP) are secretory hormones, but it is not unusual to find them in intracellular compartments. Using yeast-2 hybrid technology, we found interactions between AM and several microtubule-associated proteins (MAPs), and between PAMP and tubulin. Expression of fluorescent-tagged AM and PAMP as well as immunofluorescence for the native peptides showed a complete decoration of the microtubules and colocalization with other MAPs. PAMP, but not AM, bound to tubulin in vitro and destabilized tubulin polymerization. Down-regulation of the gene coding for both AM and PAMP through small interfering RNA technology resulted in morphological changes, microtubule stabilization, increase in posttranslational modifications of tubulin such as acetylation and detyrosination, reduction in cell motility, and partial arrest at the G2 phase of the cell cycle, when compared with cells transfected with the same vector carrying a scrambled sequence. These results show that PAMP is a novel MAP, whereas AM may be exerting more subtle effects in regulating cytoskeleton function.
Liver Receptor Homolog-1 Regulates Bile Acid Homeostasis but Is Not Essential for Feedback Regulation of Bile Acid Synthesis
Authors: Lee Youn-Kyoung , Schmidt Daniel R. , Cummins Carolyn L. , Choi Mihwa , Peng Li , Zhang Yuan , Goodwin Bryan , Hammer Robert E. , Mangelsdorf David J. , Kliewer Steven A.
Published: March 2008

Liver receptor homolog 1 (LRH-1), an orphan nuclear receptor, is highly expressed in liver and intestine, where it is implicated in the regulation of cholesterol, bile acid, and steroid hormone homeostasis. Among the proposed LRH-1 target genes in liver are those encoding cholesterol 7α-hydroxylase (CYP7A1) and sterol 12α-hydroxylase (CYP8B1), which catalyze key steps in bile acid synthesis. In vitro studies suggest that LRH-1 may be involved both in stimulating basal CYP7A1 and CYP8B1 transcription and in repressing their expression as part of the nuclear bile acid receptor [farnesoid X receptor (FXR)]-small heterodimer partner signaling cascade, which culminates in small heterodimer partner binding to LRH-1 to repress gene transcription. However, in vivo analysis of LRH-1 actions has been hampered by the embryonic lethality of Lrh-1 knockout mice. To overcome this obstacle, mice were generated in which Lrh-1 was selectively disrupted in either hepatocytes or intestinal epithelium. LRH-1 deficiency in either tissue changed mRNA levels of genes involved in cholesterol and bile acid homeostasis. Surprisingly, LRH-1 deficiency in hepatocytes had no significant effect on basal Cyp7a1 expression or its repression by FXR. Whereas Cyp8b1 repression by FXR was also intact in mice deficient for LRH-1 in hepatocytes, basal CYP8B1 mRNA levels were significantly decreased, and there were corresponding changes in the composition of the bile acid pool. Taken together, these data reveal a broad role for LRH-1 in regulating bile acid homeostasis but demonstrate that LRH-1 is either not involved in the feedback regulation of bile acid synthesis or is compensated for by other factors.
Bunker Busting and Bunker Mentalities, or Is It Safe to Be Underground?
Authors: Bell David F.
Published: March 2008

The strategic fascination with the mountain redoubts of the Taliban on Tora Bora in Afghanistan after the U.S. invasion was symptomatic of a longer cultural history of bunkers. W. G. Sebald and Paul Virilio have both written about the bunker in its World War II form, and their observations demonstrate that “bunker archeology,” as Virilio has called it, is linked to the modern history of warfare and to attempts to escape ever more destructive weapons and ever more penetrating surveillance. The American saga of nuclear fallout shelters was an avatar of this history, one that has been reactivated by the Bush administration's fetishistic desire to maintain “continuity of governance” in a so-called dangerous world. By placing ever more federal officials in bunkers on a rotating basis, the Bush administration's actions ultimately raise more fundamental questions about democratic governance itself.
Viral Sex and the Politics of Life
Authors: Tomso Gregory
Published: March 2008

The emergence of intentionally unsafe sex—“viral sex”—among men who have sex with men has led to the emergence of several new sexual identities, including barebackers, bug chasers, gift givers, and virus breeders, and it raises pressing questions about the nature of sexual freedom and the state of liberal identity politics for gay men in the United States. Avoiding subjective and psychological approaches to viral sex, this essay addresses viral sex in terms of the political economy of liberalism and biopower, featuring a discussion of Michel Foucault's late work on homosexuality and its relationship to political rationality. The central argument presented here is that viral sex functions as a powerful new claim to sexual freedom, one that provides a biopolitical alternative to the liberal politics of identity and to the dominant “culture of life” in the United States.
Safety Begins at Home
Authors: Harvey Robert
Published: March 2008

No different from the populations of any other nation, Americans aspire to comfort and safety. This essay contends that the citizens of the United States have for generations suffered from a collective historical amnesia that makes them compliant to successive political administrations bent on disastrous foreign policy. This neurosis has become acute since the 9/11 attacks. The need to analyze the problem is therefore urgent. The author attempts such an analysis and suggests visions for the day after the scales fall.
Forensics of Spinach
Authors: Willis Susan
Published: March 2008

This essay examines media accounts of the 2006 E. coli contamination of bagged spinach to piece together a forensics that demonstrates both the real and symbolic meanings of contamination. Following the path of production from field to processing plant and then to supermarket shelf, the essay maps a landscape of policed spaces and borders that have as much to do with preserving food safety as they do with providing a socially constructed sense of order. In line with anthropologist Mary Douglas's work on purity versus contamination, the essay scrutinizes the blurred boundary between organic and conventionally farmed foods, as well as the larger (possibly untenable) distinctions between nature and culture. Finally, the essay expands into a larger frame of debate to consider the way in which contamination inflects the national discourse on immigration.
Technology and the Decline of Child Labor: The Impact of the Owens Bottle Machine Reconsidered
Authors: Messer-Kruse Timothy
Published: March 2008

This article examines the relationship between the adoption of new technology and the decline of child labor in the Progressive Era by closely examining the impact automated bottle machines had on child labor in the U.S. glass industry. Historians have largely assumed that technology has acted as an independent force compelling the replacement of children by machines. However, this study shows that technology had contradictory impacts upon the employment of children, reducing it in some areas and actually stimulating greater employment of children in others, and that the adoption of this technology was highly constrained by legal structures, business strategies, and work relationships on the shop floor. In fact, this study suggests that new automated glass technologies were as much the result of the growing scarcity and rebelliousness of child workers as they were the cause for child labor's decline.
Mechanical Cleaning of Calcite Scaling with Rotating Control Head Preventer in a Geothermal Well
Authors: Yenice H. , Dünya H.
Published: March 2008

This paper presents the mechanical methods used for calcite scale cleaning of wells in the Kizildere geothermal field in Western Turkey. A geothermal power plant with a capacity of 20.4 MWe has been operating in the field since 1984. During production well diameter reduces because of calcite scaling which has been a continuous problem since the beginning of energy production from the field. The calcite scaling decreases power generation from 15 MWe to 10-12 MWe, increase capital cost, pumping costs and cleaning and maintenance costs. Scaling in the wells has been mechanically reamed periodically since 1984 to increases the production from the wells. Since mechanical cleaning with mud or water circulation causes reservoir contamination, KD 7 well was reamed while the well was flowing using Rotating Control Head Preventer (RCHP) for the first time in 1990. This method has been used successfully since 1991 at all wells. In this study the results of the mechanical cleaning with mud or water, and mechanical cleaning with Rotating Control Head Preventer methods were evaluated.
Fungal endophytes associated with Kandelia candel (Rhizophoraceae) in Mai Po Nature Reserve, Hong Kong
Authors: Pang Ka-Lai , Vrijmoed Lilian L.P. , Khiang Goh Teik , Plaingam Narumol , Jones E.B. Gareth
Published: March 2008

We examined the endophytic fungi associated with the dominant mangrove plant, Kandelia candel, in Mai Po Nature Reserve, Hong Kong. Bark, woody tissue and leaves from four mature healthy trees were sampled for fungal endophytes in April and June, 2001. A total of 880 isolates was obtained, 595 from the June sampling. The highest number of fungal endophytes was cultured from bark (674 isolates) with only 63 from leaves. Three taxa of ascomycetes, 18 of anamorphic fungi and 29 mycelial morphotypes were identified. These results indicate a degree of tissue recurrence with similar endophytic fungal assemblages in bark and wood, and a different assemblage in the leaf samples. Dominant sporulating fungi of K. candel were Phomopsis sp., Pestalotiopsis sp., Guignardia sp. and Xylaria sp., which are cosmopolitan and common endophytic species.
Sponge-associated fungi and their bioactive compounds: the Suberites case
Authors: Proksch Peter , Ebel Rainer , Edrada RuAngelie , Riebe Frank , Liu Hongbing , Diesel Arnulf , Bayer Mirko , Li Xiang , Han Lin Wen , Grebenyuk Vladislav , Müller Werner E.G. , Draeger Siegfried , Zuccaro Alga , Schulz Barbara
Published: March 2008

Specimens of Suberites domuncula that had been cultured in aquaria for 4 weeks were analyzed for their associated fungi. A total of 81 fungal strains belonging to 20 different genera was isolated and identified by morphological and molecular methods. The most frequently isolated taxa were Cladosporium spp., Penicillium spp., Petriella sp., Phialophora spp. and Engyodontium
album. Based on chromatographic and mass spectrometric analysis of fungal extracts, as well as on bioassay results, Aspergillus ustus, Penicillium sp., Petriella sp. and Scopulariopsis sp. were selected for in-depth analysis of their natural products. A total of 19 different fungal metabolites, including three new natural products, was isolated and structurally identified. A. ustus yielded two sesquiterpenes, a drimane derivative and deoxyuvidin, as well as a sesterterpene ophiobolin H. The drimane derivative had an ED50 value against L5178Y cells of 1.9 μg ml-1
in vitro. The crude extract of Petriella sp. was also strongly cytotoxic against the L5178Y cell line. The cyclic tetrapeptide WF-3161 was primarily responsible for the activity; the ED50 value was <0.1 μg ml-1. It was identical to the known compound WF-3161 and had been previously isolated from Petriella guttulata. In addition to WF-3161, three further natural products were obtained and unequivocally identified as new derivatives of infectopyrone by one- and two-dimensional NMR spectroscopy and by mass spectroscopy. Of the new compounds, only dihydroinfectopyrone was active against L5178Y cells; the ED50 value was 0.2 μg ml-1. Penicillium sp. yielded the largest number of metabolites. Viridicatin, viridicatol, cyclopenin and cyclopenol suppressed larval growth of the polyphagous pest insect Spodoptera littoralis when incorporated into an artificial diet at an arbitrarily chosen concentration of 237 ppm. Viridicatol was the most active compound and had an ED50 value of ca. 50 ppm. Scopulariopsis sp. yielded three metabolites, including the known acetylcholinesterase inhibitors quinolactacin A1 and A2.
From Martial Law to the War on Terror
Authors: Neocleous Mark
Published: March 2008

This article explores the transformation of martial law into emergency powers. In so doing it presents an argument about the liberalization of martial law and the constitutionalization of emergency powers. In showing the ways in which the powers of martial rule have become normalized within liberal democracies the article points to an ideological circuit between emergency powers and the logic of security, a circuit most apparent in the current "war on terror."