bluuebunny/crossref_metadata_2025 huggingface dataset:
Tuberculosis infection among homeless persons and caregivers in a high-tuberculosis-prevalence area in Japan: a cross-sectional study
Authors: Tabuchi Takahiro , Takatorige Toshio , Hirayama Yukio , Nakata Nobuaki , Harihara Shigeyoshi , Shimouchi Akira , Fujita Koshiro , Yoshida Hiroko , Tamura Yoshitaka , Nagai Takayuki , Matsumoto Tomoshige , Takashima Tetsuya , Iso Hiroyasu
Published: January 2011

Background

Tuberculosis (TB) is a major public health problem. The Airin district of Osaka City has a large population of homeless persons and caregivers and is estimated to be the largest TB-endemic area in the intermediate-prevalence country, Japan. However, there have been few studies of homeless persons and caregivers. The objective of this study is to detect active TB and to assess the prevalence and risk factors for latent TB infection among homeless persons and caregivers.

Methods

We conducted a cross-sectional study for screening TB infection (active and latent TB infections) using questionnaire, chest X-ray (CXR), newly available assay for latent TB infection (QuantiFERON-TB Gold In-Tube; QFT) and clinical evaluation by physicians at the Osaka Socio-Medical Center Hospital between July 2007 and March 2008. Homeless persons and caregivers, aged 30-74 years old, who had not received CXR examination within one year, were recruited. As for risk factors of latent TB infection, the odds ratios (OR) and 95% confidence intervals (95% CI) for QFT-positivity were calculated using logistic regression model.

Results

Complete responses were available from 436 individuals (263 homeless persons and 173 caregivers). Four active TB cases (1.5%) among homeless persons were found, while there were no cases among caregivers. Out of these four, three had positive QFT results. One hundred and thirty-three (50.6%) homeless persons and 42 (24.3%) caregivers had positive QFT results. In multivariate analysis, QFT-positivity was independently associated with a long time spent in the Airin district: ≥10 years versus <10 years for homeless (OR = 2.53; 95% CI, 1.39-4.61) and for caregivers (OR = 2.32; 95% CI, 1.05-5.13), and the past exposure to TB patients for caregivers (OR = 3.21; 95% CI, 1.30-7.91) but not for homeless persons (OR = 1.51; 95% CI, 0.71-3.21).

Conclusions

Although no active TB was found for caregivers, one-quarter of them had latent TB infection. In addition to homeless persons, caregivers need examinations for latent TB infection as well as active TB and careful follow-up, especially when they have spent a long time in a TB-endemic area and/or have been exposed to TB patients.
Epidemiology and trends for Caesarean section births in New South Wales, Australia: A population-based study
Authors: Stavrou Efty P , Ford Jane B , Shand Antonia W , Morris Jonathan M , Roberts Christine L
Published: January 2011

Background

Caesarean section (CS) rates around the world have been increasing and in Australia have reached 30% of all births. Robson's Ten-Group Classification System (10-group classification) provides a clinically relevant classification of CS rates that provides a useful basis for international comparisons and trend analyses. This study aimed to investigate trends in CS rates in New South Wales (NSW), including trends in the components of the 10-group classification.

Methods

We undertook a cross-sectional study using data from the Midwives Data Collection, a state-wide surveillance system that monitors patterns of pregnancy care, services and pregnancy outcomes in New South Wales, Australia. The study population included all women giving birth between 1st January 1998 and 31st December 2008. Descriptive statistics are presented including age-standardised CS rates, annual percentage change as well as regression analyses.

Results

From 1998 to 2008 the CS rate in NSW increased from 19.1 to 29.5 per 100 births. There was a significant average annual increase in primary 4.3% (95%CI 3.0-5.7%) and repeat 4.8% (95% CI 3.9-5.7%) CS rates from 1998 to 2008. After adjusting for maternal and pregnancy factors, the increase in CS delivery over time was maintained. When examining CS rates classified according to the 10-group classification, the greatest contributors to the overall CS rate and the largest annual increases occurred among nulliparae at term having elective CS and multipara having elective repeat CS.

Conclusions

Given that the increased CS rate cannot be explained by known and collected maternal or pregnancy characteristics, the increase may be related to differences in clinical decision making or maternal request. Future efforts to reduce the overall CS rate should be focussed on reducing the primary CS rate.
Oil accumulation in the model green alga Chlamydomonas reinhardtii: characterization, variability between common laboratory strains and relationship with starch reserves
Authors: Siaut Magali , Cuiné Stéphan , Cagnon Caroline , Fessler Boris , Nguyen Mai , Carrier Patrick , Beyly Audrey , Beisson Fred , Triantaphylidès Christian , Li-Beisson Yonghua , Peltier Gilles
Published: January 2011

Background

When cultivated under stress conditions, many microalgae species accumulate both starch and oil (triacylglycerols). The model green microalga Chlamydomonas reinhardtii has recently emerged as a model to test genetic engineering or cultivation strategies aiming at increasing lipid yields for biodiesel production. Blocking starch synthesis has been suggested as a way to boost oil accumulation. Here, we characterize the triacylglycerol (TAG) accumulation process in Chlamydomonas and quantify TAGs in various wild-type and starchless strains.

Results

In response to nitrogen deficiency, Chlamydomonas reinhardtii produced TAGs enriched in palmitic, oleic and linoleic acids that accumulated in oil-bodies. Oil synthesis was maximal between 2 and 3 days following nitrogen depletion and reached a plateau around day 5. In the first 48 hours of oil deposition, a ~80% reduction in the major plastidial membrane lipids occurred. Upon nitrogen re-supply, mobilization of TAGs started after starch degradation but was completed within 24 hours. Comparison of oil content in five common laboratory strains (CC124, CC125, cw15, CC1690 and 11-32A) revealed a high variability, from 2 μg TAG per million cell in CC124 to 11 μg in 11-32A. Quantification of TAGs on a cell basis in three mutants affected in starch synthesis (cw15sta1-2, cw15sta6 and cw15sta7-1) showed that blocking starch synthesis did not result in TAG over-accumulation compared to their direct progenitor, the arginine auxotroph strain 330. Moreover, no significant correlation was found between cellular oil and starch levels among the twenty wild-type, mutants and complemented strains tested. By contrast, cellular oil content was found to increase steeply with salt concentration in the growth medium. At 100 mM NaCl, oil level similar to nitrogen depletion conditions could be reached in CC124 strain.

Conclusion

A reference basis for future genetic studies of oil metabolism in Chlamydomonas is provided. Results highlight the importance of using direct progenitors as control strains when assessing the effect of mutations on oil content. They also suggest the existence in Chlamydomonas of complex interplays between oil synthesis, genetic background and stress conditions. Optimization of such interactions is an alternative to targeted metabolic engineering strategies in the search for high oil yields.
Prevalence and risk factors accounting for true silent myocardial ischemia: a pilot case-control study comparing type 2 diabetic with non-diabetic control subjects
Authors: Hernández Cristina , Candell-Riera Jaume , Ciudin Andreea , Francisco Gemma , Aguadé-Bruix Santiago , Simó Rafael
Published: January 2011

Background

Given the elevated risk of cardiovascular events and the higher prevalence of silent coronary artery disease (CAD) in diabetic versus non-diabetic patients, the need to screen asymptomatic diabetic patients for CAD assumes increasing importante. The aims of the study were to assess prospectively the prevalence and risk factor predictors of true silent myocardial ischemia (myocardial perfusion defects in the absence of both angina and ST-segment depression) in asymptomatic type 2 diabetic patients.

Methods

Stress myocardial perfusion gated SPECT (Single Photon Emission Computed Tomography) was carried out in 41 type 2 diabetic patients without history of cardiovascular disease (CVD) and 41 nondiabetic patients matched by age and gender.

Results

There were no significant differences between the two groups regarding either the classic CVD risk factors or left ventricular function. True silent ischemia was detected in 21.9% of diabetic patients but only in 2.4% of controls (p < 0.01). The presence of myocardial perfusion defects was independently associated with male gender and the presence of diabetic retinopathy (DR). The probability of having myocardial perfusion defects in an asymptomatic diabetic patient with DR in comparison with diabetic patients without DR was 11.7 [IC95%: 3.7-37].

Conclusions

True silent myocardial ischemia is a high prevalent condition in asymptomatic type 2 diabetic patients. Male gender and the presence of DR are the risk factors related to its development.
Induction of ovulation in Xenopuswithout hCG injection: the effect of adding steroids into the aquatic environment
Authors: Ogawa Aoi , Dake Junpei , Iwashina Yu-ki , Tokumoto Toshinobu
Published: January 2011

Background

The African clawed frog, Xenopus laevis, is widely used in studies of oogenesis, meiotic cell cycle and early embryonic development. However, in order to perform such studies, eggs are normally collected after the injection of hCG into the dorsal lymph sac of fully-grown female frogs following pre-injection of PMSF. Although this protocol is established and used as standard laboratory approach, there are some concerns over whether the injections could cause the transmission of deleterious microorganisms. Moreover, these injection protocols require a competent skilled worker to carry out the procedure efficiently.

Methods

Recently, we established a novel method to induce fish ovulation by simply adding the natural maturation-inducing hormone of teleosts, 17 alpha, 20 beta-dihydroxy-4-pregnen-3-one (17,20 beta-DHP), into the surrounding water. In the present study, we demonstrate how we can induce ovulation in frogs using the same methodology.

Results

In frogs, progesterone was effective in the induction of oocyte maturation in vitro. We then examined the ability of progesterone to induce ovulation in frogs. However treatment of frogs with progesterone alone only occasionally induced ovulation in vivo. The number of oocytes and the frequency of ovulation were significantly lower than that induced by hCG-injection. Thus, conditions were improved by using a combination of progesterone with estradiol and by pre-treating frogs with low concentrations of progesterone or estradiol. Finally, we established an efficient means of inducing ovulation in frogs which involved pre-treatment of frogs with salt solution followed by a mixture of estradiol and progesterone at high concentration. The frequency and numbers of oocytes obtained were identical to those resulting from PMSG-hCG induction. Fertilization rate of eggs ovulated by the new treatment method was comparable to eggs obtained by hCG-injection and juveniles developed normally.

Conclusions

To conclude, we have successfully developed a novel method to induce ovulation in frogs but without the need for a potentially harmful injection strategy.
Core shell hybrids based on noble metal nanoparticles and conjugated polymers: synthesis and characterization
Authors: Fratoddi Ilaria , Venditti Iole , Battocchio Chiara , Polzonetti Giovanni , Cametti Cesare , Russo Maria Vittoria
Published: January 2011

Noble metal nanoparticles of different sizes and shapes combined with conjugated functional polymers give rise to advanced core shell hybrids with interesting physical characteristics and potential applications in sensors or cancer therapy. In this paper, a versatile and facile synthesis of core shell systems based on noble metal nanoparticles (AuNPs, AgNPs, PtNPs), coated by copolymers belonging to the class of substituted polyacetylenes has been developed. The polymeric shells containing functionalities such as phenyl, ammonium, or thiol pending groups have been chosen in order to tune hydrophilic and hydrophobic properties and solubility of the target core shell hybrids. The Au, Ag, or Pt nanoparticles coated by poly(dimethylpropargylamonium chloride), or poly(phenylacetylene-co-allylmercaptan). The chemical structure of polymeric shell, size and size distribution and optical properties of hybrids have been assessed. The mean diameter of the metal core has been measured (about 10-30 nm) with polymeric shell of about 2 nm.
A reporter system for assaying influenza virus RNP functionality based on secreted Gaussia luciferase activity
Authors: Zhu Wenfei , Zhou Jianfang , Qin Kun , Du Ning , Liu Liqi , Yu Zaijiang , Zhu Yun , Tian Wenhong , Wu Xiaobing , Shu Yuelong
Published: January 2011

Background

Influenza A virus can infect a wide variety of animal species including humans, pigs, birds and other species. Viral ribonucleoprotein (vRNP) was involved in genome replication, transcription and host adaptation. Currently, firefly luciferase (Fluc) reporter system was used in vRNP functional assay. However, its limitation for the testing by virus infection resulted in an increased need for rapid, sensitive, and biosafe techniques. Here, an influenza A virus UTR-driven gene reporter for vRNP assay based on secreted Gaussia luciferase (Gluc) activity was evaluated.

Results

By measuring Gluc levels in supernatants, reporter gene activity could be detected and quantitated after either reconstitution of influenza A virus polymerase complex or viral infection of 293T and A549 cells, respectively. As compared with Fluc reporter, Gluc-based reporter was heat-tolerant (65°C for 30 min) and produced 50-fold higher bioluminescent activity at 24 h posttransfection. Signals generated by Gluc reporter gene could be detected as early as 6 h post-infection and accumulated with time. Testing by viral infection, stronger signals were detected by Gluc reporter at a MOI of 0.001 than that of 1 and the effects of PB2-627K/E or amantadine on influenza vRNP activity were elucidated more effectively by the Gluc reporter system.

Conclusions

This approach provided a rapid, sensitive, and biosafe assay of influenza vRNP function, particularly for the highly pathogenic avian influenza viruses.
Improved hatchability and efficient protection after in ovo vaccination with live-attenuated H7N2 and H9N2 avian influenza viruses
Authors: Cai Yibin , Song Haichen , Ye Jianqiang , Shao Hongxia , Padmanabhan Rangarajan , Sutton Troy C , Perez Daniel R
Published: January 2011

Mass in ovo vaccination with live attenuated viruses is widely used in the poultry industry to protect against various infectious diseases. The worldwide outbreaks of low pathogenic and highly pathogenic avian influenza highlight the pressing need for the development of similar mass vaccination strategies against avian influenza viruses. We have previously shown that a genetically modified live attenuated avian influenza virus (LAIV) was amenable for in ovo vaccination and provided optimal protection against H5 HPAI viruses. However, in ovo vaccination against other subtypes resulted in poor hatchability and, therefore, seemed impractical. In this study, we modified the H7 and H9 hemagglutinin (HA) proteins by substituting the amino acids at the cleavage site for those found in the H6 HA subtype. We found that with this modification, a single dose in ovo vaccination of 18-day old eggs provided complete protection against homologous challenge with low pathogenic virus in ≥70% of chickens at 2 or 6 weeks post-hatching. Further, inoculation of 19-day old egg embryos with 106 EID50 of LAIVs improved hatchability to ≥90% (equivalent to unvaccinated controls) with similar levels of protection. Our findings indicate that the strategy of modifying the HA cleavage site combined with the LAIV backbone could be used for in ovo vaccination against avian influenza. Importantly, with protection conferred as early as 2 weeks post-hatching, with this strategy birds would be protected prior to or at the time of delivery to a farm or commercial operation.
GM-CSF and IL-2 as adjuvant enhance the immune effect of protein vaccine against foot-and-mouth disease
Authors: Zhang Can , Wang Bin , Wang Ming
Published: January 2011

Background

Cytokines as molecular adjuvant play a critical role in differentiation of effector T cell subsets and in determination of the magnitude of the response after vaccination. In this study, we investigated the effects of GM-CSF and IL-2 as adjuvant on the immune responses of VP1 recombinant protein as a model antigen for foot and mouth disease.

Results

Six expression plasmids were constructed and expressed in E. coli BL21. In guinea pigs, the immunological and molecular effects of the fusion proteins were determined by ELISA, LPA, DTH and semi-quantitative Reverse Transcriptase PCR (RT-PCR). The data revealed that IL-2 and GM-CSF as adjuvant of VP1 could stimulate both humoral and cell-mediated immune response. Interestingly, IL-2 and GM-CSF, either as a co-expressed protein or as a mixture of two single proteins, showed much better adjuvant effects than that of single one.

Conclusions

IL-2 and GM-CSF could be used as a potential adjuvant for VP1 and had synergistic effect when co-expressed or mixed with VP1.
Primary acantholytic squamous cell carcinoma of the cecum: a case report
Authors: Jukić Zoran , Ledinsky Iva , Ulamec Monika , Ledinsky Mario , Krušlin Božo , Tomas Davor
Published: January 2011

Background

Acantholytic squamous cell carcinoma (ASCC) is an uncommon histopathologic variant of SCC, characterized by marked acantholysis, wherein the tumor cells demonstrate defective cohesion to one another in the cancer nest leading to a pseudoglandular or pseudovascular appearance. The most common site of ASCC is the sun-exposed areas of the skin. Sporadic cases of ASCC have also been reported in various mucosal membranes and organs but to our knowledge this is the first case of primary ASCC of the large bowel.

Case presentation

A 59-year-old woman underwent right hemicolectomy due to large tumor in cecum and initial part of the ascending colon. Microscopically, the tumor consisted of nests of focally keratinizing large, atypical, squamous epithelial cells. Approximately 70% of the tumor showed acantholytic changes and acantholysis was equally distributed through the entire tumor. Immunohistochemically tumor cells were diffusely positive for cytokeratin (CK) AE1/AE3 and focally positive for epithelial membrane antigen and syndecan 1. All other tested antibodies (CK7, CK 20, CK MNF116, E-cadherin, beta-catenin, p63, p16, CD31, CD34, CEA, estrogen, progesterone) showed negative reaction. Periodic acid Schiff and alcian blue staining showed no intracellular or extracellular mucinous material in the tumor. The diagnosis of acantholytic squamous cell carcinoma of the cecum was suspected and additional examination was recommended to exclude possibility of metastatic carcinoma. Extensive clinical examination which also included whole-body PET/CT scan showed no additional tumors. After the exclusion of possible metastatic disease the diagnosis of primary acantholytic squamous cell carcinoma of the cecum was confirmed. Six months after surgery the metastasis in small intestine and recurrence in the abdominal cavity at the site of surgery appeared and had the same morphological characteristic as the primary tumor in the cecum.

Conclusion

We report a unique case of ASCC arising in cecum and on this way expands the range of tumors originating in colon. Reports of more cases of colonic ASCC would possibly help to elucidate origin, clinical behavior and therapy of these tumors.
Perceptions and attitudes of bhutanese people on Sowa Rigpa, traditional bhutanese medicine: a preliminary study from Thimphu
Authors: Lhamo Namgay , Nebel Sabine
Published: January 2011

Background

Many claims are made that the use of traditional medicine is a substantial and growing part of healthcare behavior around the world. In Bhutan traditional medical practice is one of the country's tangible heritages. The country hosts two forms of traditional medicines: local healing practices and the official traditional medical system known as sowa rigpa, meaning "the science of healing". This paper explores the attitudes on sowa rigpa among Bhutanese living in Thimphu, the capital of Bhutan.

Methods

This study was conducted from May to September 2009. In total, 155 people coming from diverse social backgrounds were randomly selected for the study. The study made use of qualitative as well as quantitative approaches, involving the administration of questionnaires and conducting in-depth interviews.

Results

From the 155 respondents 99% have heard about sowa rigpa, mainly from their friends or relatives. The study showed that sowa rigpa is popular among the respondents since more than half (51%) have said that they have been treated by sowa rigpa doctors. The data revealed that the majority (83%) of the respondents are satisfied with the treatment received.

Conclusion

The Bhutanese healthcare system that integrates sowa rigpa and modern medicine offers an opportunity for active healthcare decision-making by the patients. The improved understanding of the knowledge, attitudes and treatment seeking practices of the participants in the study provides useful information for health practitioners and policy makers to plan health activities. The present preliminary study represents only people living in the capital city of Bhutan. Therefore, a further nationwide study is planned to better understand the role sowa rigpa plays also in rural Bhutan.
Peripheral muscarinic receptors mediate the anti-inflammatory effects of auricular acupuncture
Authors: Chung Wai Yeung , Zhang Hong Qi , Zhang Shi Ping
Published: January 2011

Background

The cholinergic and opioid systems play important roles in modulating inflammation. This study tests whether auricular acupuncture (AA) produces anti-inflammatory effects via opioid and peripheral cholinergic receptors in a rat model.

Methods

Rats were anesthetized with chloral hydrate and inflammation was induced by intraplantar injection of carrageenan. Electroacupuncture was performed at auricular points bilaterally. The severity of inflammation was assessed using changes in paw volume and thermal and mechanical pain thresholds of the rats during recovery from anesthesia.

Results

Electroacupuncture at selected auricular acupoints significantly reduced paw edema and mechanical hyperalgesia, with no significant effect on thermal hyperalgesia. The anti-edematous and analgesic effects of AA were abolished by blockade of peripheral cholinergic muscarinic receptors with methyl atropine. Blockade of local muscarinic receptors at the inflamed site with a small dose of atropine also antagonized the anti-edematous effect of AA. By contrast, systemic opioid receptor blockade with naloxone did not antagonize the anti-inflammatory effects of AA.

Conclusion

This study discovers a role of peripheral muscarinic receptors in mediating the anti-inflammatory effects of AA. The cholinergic muscarinic mechanism appears to be more important than the opioid mechanism in the anti-inflammatory action of AA.
SPABBATS: A pathway-discovery method based on Boolean satisfiability that facilitates the characterization of suppressor mutants
Authors: Flórez Lope A , Gunka Katrin , Polanía Rafael , Tholen Stefan , Stülke Jörg
Published: January 2011

Background

Several computational methods exist to suggest rational genetic interventions that improve the productivity of industrial strains. Nonetheless, these methods are less effective to predict possible genetic responses of the strain after the intervention. This problem requires a better understanding of potential alternative metabolic and regulatory pathways able to counteract the targeted intervention.

Results

Here we present SPABBATS, an algorithm based on Boolean satisfiability (SAT) that computes alternative metabolic pathways between input and output species in a reconstructed network. The pathways can be constructed iteratively in order of increasing complexity. SPABBATS allows the accumulation of intermediates in the pathways, which permits discovering pathways missed by most traditional pathway analysis methods. In addition, we provide a proof of concept experiment for the validity of the algorithm. We deleted the genes for the glutamate dehydrogenases of the Gram-positive bacterium Bacillus subtilis and isolated suppressor mutant strains able to grow on glutamate as single carbon source. Our SAT approach proposed candidate alternative pathways which were decisive to pinpoint the exact mutation of the suppressor strain.

Conclusions

SPABBATS is the first application of SAT techniques to metabolic problems. It is particularly useful for the characterization of metabolic suppressor mutants and can be used in a synthetic biology setting to design new pathways with specific input-output requirements.
Strategic Entry Deterrence and the Behavior of Pharmaceutical Incumbents Prior to Patent Expiration
Authors: Ellison Glenn , Ellison Sara Fisher
Published: January 2011

This paper develops a new approach to testing for strategic entry deterrence and applies it to the behavior of pharmaceutical incumbents before patent expiration. It examines a cross section of markets, determining whether behavior is nonmonotonic in market size. Under some conditions, investment levels will be monotone in market size if firms do not invest to deter entry. Strategic investments to deter entry, however, may result in nonmonotonic investment because they are unnecessary in small markets, and impossible in large ones. Consistent with an entry-deterrence motivation is the finding that incumbents in medium-sized markets advertise less prior to patent expiration. (JEL D92, G31, L11, L21, L65)
Product Recalls in the Medical Device Industry: An Empirical Exploration of the Sources and Financial Consequences
Authors: Thirumalai Sriram , Sinha Kingshuk K.
Published: January 2011

Medical devices play an increasingly significant role in the delivery of health care today. However, persistent quality problems with medical devices and the associated recalls present potential health risks to patients and personnel using these devices. This study addresses three key issues in this regard. First, it empirically assesses the financial implications of medical device recalls to understand if these consequences are severe enough to deter firms from introducing potentially hazardous medical devices into the market, as can be inferred from the literature. Second, the study considers a cross section of medical device manufacturers to examine the effect of firm characteristics on the costs of poor quality. Third, in an attempt to explore the sources of recalls, this study investigates firm characteristics that are likely to be associated with device recalls. The econometric analyses in the study are based on data from manufacturers in the medical device industry over a four-year period (2002–2005). Contrary to our expectations, the findings of the study indicate that at an aggregate level, the market penalties for medical device recalls are not significant, i.e., at the aggregate level, the costs of poor quality are not severe. Furthermore, we find that the magnitude of financial consequences of device recalls is affected by the product scope, sales, growth prospects, and the capital structure of a firm. In our analyses exploring the sources of device recalls, we find that firms with a research and development focus, developing broader product portfolios, have a higher likelihood of device recalls. Also, we find that the likelihood of recalls decreases with prior recall experience, indicating the presence of learning. Implications of the study findings, limitations, and directions for future research are identified.

This paper was accepted by Sampath Rajagopalan, operations and supply chain management.
Managing Consumer Returns in a Competitive Environment
Authors: Shulman Jeffrey D. , Coughlan Anne T. , Savaskan R. Canan
Published: January 2011

This paper investigates the pricing and restocking fee decisions of two competing firms selling horizontally differentiated products. We model a duopoly facing consumers who have heterogeneous tastes for the products and who must experience a product before knowing how well it matches with their preferences. The analysis yields several key insights. Restocking fees not only can be sustained in a competitive environment, but also are more severe when consumers are less informed about product fit and when consumers place a greater importance on how well products' attributes fit with their preferences. We compare the competitive equilibrium prices to a scenario in which consumers are certain about their preferences and find conditions defining when consumer uncertainty results in higher equilibrium prices. Comparison to a monopoly setting yields a surprising result: Equilibrium restocking fees in a competitive environment can be higher than those charged by a monopolist.

This paper was accepted by Jagmohan S. Raju, marketing.
Enantioselective construction of new chiral cyclic scaffolds using [2 + 2 + 2] cycloaddition
Authors: Shibata Takanori , Uchiyama Toshifumi , Hirashima Hiroyuki , Endo Kohei
Published: January 2011

Two types of enantioselective [2 + 2 + 2] cycloadditions of triynes using chiral rhodium catalysts are disclosed. The intramolecular reaction of ortho-aminophenol-tethered triynes provides chiral tripodal compounds. Consecutive inter- and intramolecular reactions of ortho-phenylene-tethered triynes provide chiral tetraphenylenes.
Glucocorticoid signaling in cardiac disease
Authors: Ren Rongqin , Cidlowski John A.
Published: January 2011

As major mediators of stress regulation, glucocorticoids have an essential role in maintaining cardiovascular homeostasis under both physiological and pathological conditions. The release of glucocorticoids into the peripheral circulation is adjusted by the hypothalamic-pituitary-adrenal axis in response to various pathological challenges such as sepsis, starvation, and psychological stress. Clinically, dysregulation of the glucocorticoid-mediated signaling as a result of either excess ligand or receptor hypersensitivity is connected with the progression of unfavorable cardiovascular events such as cardiac hypertrophy, atherosclerosis, and coronary artery disease. The direct effects of glucocorticoids on cardiac tissues are mediated by two steroid receptors, the glucocorticoid receptor and mineralocorticoid receptor, which are both expressed by cardiomyocytes. Although each receptor has some shared responses to glucocorticoids, each receptor also has unique effects on cardiac functions. Elucidating the selective actions of each receptor is critical for determining the proper pharmaceutical targets in cardiovascular diseases.
Estrogens and progestins: molecular effects on brain cells
Authors: Mannella Paolo , Simoncini Tommaso , Genazzani Andrea Riccardo
Published: January 2011

Sex steroids are known to regulate brain function and their role is so important that several diseases are strictly correlated with the onset of menopause when estrogen-progesterone deficiency makes neural cells much more vulnerable to toxic stimuli. Although in the past years several scientists have focused their studies on in vitro and in vivo effects of sex steroids on the brain, we are still far from complete knowledge. Indeed, contrasting results from large clinical trials have made the entire issue much more complicated. Currently we know that protective effects exerted by sex steroids depend on several factors among which the dose, the health of the cells and the type of molecule being used. In this review, we present an overview of the direct and indirect effects of estrogen and progesterone on the brain with specific focus on the molecular mechanisms by which these molecules act on neural cells.
Towards a systemic profile of the Spanish MOOD
Authors: Quiroz Beatriz
Published: January 2011

The aim of this paper is to explore the MOOD system of the Spanish clause, as a region of interpersonal meaning within the framework of Systemic Functional Linguistics (hereafter, SFL). Given the paradigmatic perspective privileged in SFL descriptions, the focus here is on the choices underlying the different lexicogrammatical structures used by Spanish speakers in verbal exchanges, in particular, the resources available for the exchange of information and goods and services in dialogue. The variety addressed in this account is Chilean Spanish; the descriptive focus is on the (simple) clause and the (verbal) group. Key interpersonal features are first addressed from the perspective of discourse semantics, beginning with the exploration of the key negotiatory features of the organisation of the clause, and moving on to the realisation of ‘subjecthood’ and ‘finiteness’. Subsequently, a general MOOD system network is outlined, including discussion of the systemic contrasts motivating its features and their structural realisation. Finally, a number of issues emerging from this discussion are raised.
“As hard as it gets”
Authors: Garcia Alexandra Isabel
Published: January 2011

The turn of the century marked an escalation of the violence of the Colombian conflict by both Marxist guerrillas and right wing paramilitaries. However, popular perception of each group contrasts sharply with the statistics on responsibility for criminal acts. Since the press is one of the main sources of information on the conflict for the general population, analyzing the way in which it reconstructs these events may provide some insights into this phenomenon. Thus, as an initial step in this process, two pieces of news on violent acts perpetrated by each group reported in ‘El Tiempo’, the leading Colombian newspaper, in December 1998 are analysed. Within a Systemic Functional Linguistics framework, it will contrast who the participants are in each text and how they are nominated, what types of processes they carry out, and how explicitly causation is attributed. The analysis shows how despite having the same context, the experiential meanings realized in the lexicogrammatical selections of each text construe a remarkably different semiotic space.
Patterns of Richness, Composition, and Distribution of Sphingid Moths Along an Elevational Gradient in the Andes-Amazon Region of Southeastern Peru
Authors: Ignatov Igor I , Janovec John P , Centeno Pedro , Tobler Mathias W , Grados Juan , Lamas Gerardo , Kitching Ian J
Published: January 2011

The adult sphingid communities of three sites in southeastern Peru representative of the moist tropical forest of the lowland Amazon, the pluvial tropical forest of the upper Amazon and Andean foothills, and the montane cloud forest of the eastern slopes of the Andes were sampled during 2004–2006 by using mercury vapor light traps. In total, 119 species of Sphingidae were documented. Species diversity was highest in the upper Amazon and Andean foothills, with 94 species (21 genera), followed by 80 species (21 genera) in the Amazonian lowlands, and 43 species (17 genera) in the montane cloud forest. The greatest number of endemics (22) was registered at the upper AmazonAndean foothills site. The montane cloud forest site was characterized by the highest relative percentage of endemic species. The species assemblages of the lowland Amazon and the Andean foothills were more similar in composition to each other than to the montane assemblage. All three assemblages proved to be more distinctive than expected based on the proximity of the sampled sites and seemingly good flight capabilities of sphingid moths. This was reflected by the endemics accounting for nearly 40% of the total species pool. By contrast, cosmopolitans numbered only 26 species, or 22% of the total assemblage. We hypothesize that the composition and distribution of sphingid species along this elevational gradient may reflect floristic similarities and differences between the study sites and the extent to which different species are adapted to cope with certain environmental conditions, such as temperature and air humidity.
Larval Development ofDiaphorencyrtus aligarhensis(Hymenoptera: Encyrtidae), an Endoparasitoid ofDiaphorina citri(Hemiptera: Psyllidae)
Authors: Rohrig Eric , Shirk Paul D , Hall David G , Stansly Philip A
Published: January 2011

The koinobiont endoparasitoid Diaphorencyrtus aligarhensis (Shafee, Alam & Agarwal) (Hymenoptera: Encyrtidae) is an imported biological control agent being released in Florida against the Asian citrus psyllid, Diaphorina citri Kuwayama (Hemiptera: Psyllidae). The eggs and early larvae were found free floating within the hemocoel. Larvae were soft bodied with no observable hairs, bristles, or external appendages, such as anal vesicles, in any instar. By the third instar, larvae had begun attaching to nymphal tissues by anal secretions that provided a means of orienting within the host nymph. The penultimate and last-instar larvae were found with their posterior anchored in the head—thoracic region of the host with their head oriented toward the posterior of the host nymph. Before the beginning of the prepupal stage, the host nymph was turned into a mummy and glued to a plant surface, apparently requiring some secretions from the wasp larva. Development from oviposition to adult eclosion of D. aligarhensis took ≈16 d at 25°C when oviposition occurred in second-through early fourth-instar nymphs, although this time was shortened by 4 d (25%) when the wasps oviposited in mid-fourth-instar D. citri nymphs. This reduction in developmental time did not affect wasp fertility or life span and may offer a significant approach to improved rearing of this wasp for augmentative releases to control the Asian citrus psyllid.
Assessing Alternative Measures of Wealth in Health Research
Authors: Cubbin Catherine , Pollack Craig , Flaherty Brian , Hayward Mark , Sania Ayesha , Vallone Donna , Braveman Paula
Published: January 2011

Objectives. We assessed whether it would be feasible to replace the standard measure of net worth with simpler measures of wealth in population-based studies examining associations between wealth and health.

Methods. We used data from the 2004 Survey of Consumer Finances (respondents aged 25–64 years) and the 2004 Health and Retirement Survey (respondents aged 50 years or older) to construct logistic regression models relating wealth to health status and smoking. For our wealth measure, we used the standard measure of net worth as well as 9 simpler measures of wealth, and we compared results among the 10 models.

Results. In both data sets and for both health indicators, models using simpler wealth measures generated conclusions about the association between wealth and health that were similar to the conclusions generated by models using net worth. The magnitude and significance of the odds ratios were similar for the covariates in multivariate models, and the model-fit statistics for models using these simpler measures were similar to those for models using net worth.

Conclusions. Our findings suggest that simpler measures of wealth may be acceptable in population-based studies of health.
Civil society: a revived mantra in the development discourse
Authors: Suleiman Lina
Published: January 2011

There is an assumption that the inclusion of civil society in governance processes promotes democratic performance and contributes to ‘good governance’, in the sense of pluralism, accountability and transparency. This paper refers to the governance process of the water utility in Accra involving the private sector, and examines the validity of the assumed roles regarding the inclusion of civil society in the governance process. For the purposes of this study, civil society is defined as ‘non-state and non-market organisations that can, or have the potential to, champion democratic governance reforms and act as agents for political and socio-economic change’. Contrary to assumptions made about the inclusion of civil society, the analysis herein shows that the inclusion of civil groups in the governance process of the water utility led to hostile and undemocratic processes and to weak indicators of ‘good governance’. The main concern of the key actors was centred on how to build consensus around the privatisation programme of the water utility. ‘Managing consensus’, however, is an inappropriate planning measure. It is argued here that the focus should rather be on how to design governance structures and arrangements, mobilised by legitimate and committed political leadership, to build and enhance the capacity of governance processes.
Transplantation of mesenchymal stem cells and nucleus pulposus cells in a degenerative disc model in rabbits: a comparison of 2 cell types as potential candidates for disc regeneration
Authors: Feng Ganjun , Zhao Xianfeng , Liu Hao , Zhang Huina , Chen Xiangjun , Shi Rui , Liu Xi , Zhao Xiaodan , Zhang Wenli , Wang Beiyu
Published: January 2011

Object

The aim of this study was to compare transplanted mesenchymal stem cells (MSCs) with nucleus pulposus cells (NPCs) in a degenerative disc model in rabbits to determine the better candidate for disc cell therapy.

Methods

Mesenchymal stem cells and NPCs were transplanted in a rabbit model of disc degeneration. Changes in disc height, according to plain radiography, T2-weighted signal intensity on MR imaging, histology, sulfated glycosaminoglycan (sGAG)/DNA, and associated gene expression levels, were evaluated among healthy controls without surgery, sham-operated animals in which only disc degeneration was induced, MSC-transplanted animals, and NPC-transplanted animals for a 16-week period.

Results

Sixteen weeks after cell transplantation, in the MSC- and NPC-transplanted groups, the decline in the disc height index was reduced and T2-weighted signal intensity increased compared with the sham-operated group. Safranin O staining showed a high GAG content, which was also supported by sGAG/DNA assessment. Disc regeneration was also confirmed at the gene expression level using real-time polymerase chain reaction. However, no significant differences in expression were found between the NPC- and MSC-transplanted groups.

Conclusions

Study data showed that MSC transplantation is effective for the treatment of disc degeneration and seems to be an ideal substitute for NPCs.
Volumetric myelographic magnetic resonance imaging to localize difficult-to-find spinal dural arteriovenous fistulas
Authors: Morris Jonathan M. , Kaufmann Timothy J. , Campeau Norbert G. , Cloft Harry J. , Lanzino Giuseppe
Published: January 2011

Although more prevalent in males in the 6th and 7th decade of life, spinal dural arteriovenous fistulas (SDAVFs) are an uncommon cause of progressive myelopathy. Magnetic resonance imaging and more recently Gd bolus MR angiography have been used to diagnose, radiographically define, and preprocedurally localize the contributing lumbar artery. Three-dimensional myelographic MR imaging sequences have recently been developed for anatomical evaluation of the spinal canal. The authors describe 3 recent cases in which volumetric myelographic MR imaging with a 3D phase-cycled fast imaging employing steady state acquisition (PC-FIESTA) and a 3D constructive interference steady state (CISS) technique were particularly useful not only for documenting an SDAVF, but also for providing localization when CT angiography, MR imaging, MR angiography, and spinal angiography failed to localize the fistula. In a patient harboring an SDAVF at T-4, surgical exploration was performed based on the constellation of findings on the PC-FIESTA images as well as the fact that the spinal segments leading to T-4 were the only ones that the authors were unable to catheterize. In a second patient, who harbored an SDAVF at T-6, after 2 separate angiograms failed to demonstrate the fistula, careful assessment of the CISS images led the authors to focus a third angiogram on the left T-6 intercostal artery and to perform superselective microcatheterization. In a third patient with an SDAVF originating from the lateral sacral branch, the PC-FIESTA sequence demonstrated the arterialized vein extending into the S-1 foramen, leading to a second angiogram and superselective internal iliac injections. The authors concluded that myelographic MR imaging sequences can be useful not only as an aid to diagnosis but also for localization of an SDAVF in complex cases.
The natural history of intracranial meningiomas
Authors: Oya Soichi , Kim Seon-Hwan , Sade Burak , Lee Joung H.
Published: January 2011

Object

Despite the increased detection of incidental or small meningiomas, the lesion's natural history is largely unknown.

Methods

One year or longer of follow-up was conducted in 244 patients with 273 meningiomas managed conservatively by a single surgeon between 2003 and 2008. Data were stratified according to age, sex, tumor location, symptoms, initial tumor diameter, calcification, MR imaging intensity, and edema. Linear tumor growth was defined as a 2-mm or larger increase in the maximum diameter in any direction of the tumor. Volumetric analysis (ImageJ version 1.43) was also conducted in 154 of 273 meningiomas for which complete radiological data were available in the form of DICOM files throughout the follow-up period. A volume increase greater than 8.2% was regarded as significant because the preliminary volumetry based on 20 randomly selected meningiomas showed that the average SD was 4.1%.

Results

Linear growth was observed in 120 tumors (44.0%) with a mean follow-up of 3.8 years. Factors related to tumor growth were age of 60 or younger (p = 0.0004), absence of calcification (p = 0.027), MR imaging T2 signal hyperintensity (p = 0.021), and edema (p = 0.018). Kaplan-Meier analysis and Cox proportional hazards regression analysis revealed that age 60 or younger (hazard ratio [HR] 1.54, 95% CI 1.05–2.30, p = 0.026), initial tumor diameter greater than 25 mm (HR 2.23, 95% CI 1.44–3.38, p = 0.0004), and the absence of calcification (HR 4.57, 95% CI 2.69–8.20, p < 0.0001) were factors associated with a short time to progression. Volumetric growth was seen in 74.0% of the cases. Factors associated with a higher annual growth rate were male sex (p = 0.0002), initial tumor diameter greater than 25 mm (p < 0.0001), MR imaging T2 signal hyperintensity (p = 0.0001), presence of symptoms (p = 0.037), and edema (p < 0.0001).

Conclusions

Although the authors could obtain variable results depending on the measurement method, the data demonstrate patients younger than 60 years of age and those with meningiomas characterized by hyperintensity on T2-weighted MR imaging, no calcification, diameter greater than 25 mm, and edema need to be observed more closely. Volumetry was more sensitive to detecting tumor growth than measuring the linear diameter.
Model for Submarine Glacial Deposition
Authors: Orheim Olav , Elverhøi Anders
Published: January 2011

Present-day sedimentary environments in the eastern Weddell Sea confirm low clastic sediment input from wide (> 100 km) ice shelves. Mainly bioclastic sediments are formed in situ on the inner and shallow central-shelf areas (250 to 350 m water depth), with sedimentation rates probably < 0.01 m ka−3. Ice-rafted debris (IRD) is mainly deposited on the outer shelf and upper continental slope, with a sedimentation rate of 0.02 to 0.07 m ka−3. The coarse-grained texture of these deposits is caused by removal of finer grades in suspension during settling of IRD sediments. Overconsolidated till was deposited < 31 ka BP during expansion of grounded ice to the shelf break. Subsequent eustatic rise caused grounded ice to float. Frozen-on sediments melted out of the base of the ice, depositing soft pebbly mud above the till. Marine conditions similar to present-day conditions were found for the interval 30 to 40 ka BP.

IRD variation is an indicator of ice-shelf coverage and changes in relative sea-level, and is, in low latitudes, probably inversely related to the degree of ice cover.