bluuebunny/crossref_metadata_2025_split huggingface dataset:
Cytosine arabinoside induces ectoderm and inhibits mesoderm expression in human embryonic stem cells during multilineage differentiation
Authors: Jagtap S , Meganathan K , Gaspar J , Wagh V , Winkler J , Hescheler J , Sachinidis A 
Published: December 2010

BACKGROUND AND PURPOSE Teratogenic substances induce adverse effects during the development of the embryo. Multilineage differentiation of human embryonic stem cells (hESCs) mimics the development of the embryo in vitro. Here, we propose a transcriptomic approach in hESCs for monitoring specific toxic effects of compounds as an alternative to traditional time‐consuming and cost‐intensive in vivo tests requiring large numbers of animals. This study was undertaken to explore the adverse effects of cytosine arabinoside (Ara‐C) on randomly differentiated hESCs.EXPERIMENTAL APPROACH Human embryonic stem cells were used to investigate the effects of a developmental toxicant Ara‐C. Sublethal concentrations of Ara‐C were given for two time points, day 7 and day 14 during the differentiation. Gene expression was assessed with microarrays to determine the dysregulated transcripts in presence of Ara‐C.KEY RESULTS Randomly differentiated hESCs were able to generate the multilineage markers. The low concentration of Ara‐C (1 nM) induced the ectoderm and inhibited the mesoderm at day 14. The induction of ectodermal markers such as MAP2, TUBB III, PAX6, TH and NESTIN was observed with an inhibition of mesodermal markers such as HAND2, PITX2, GATA5, MYL4, TNNT2, COL1A1 and COL1A2. In addition, no induction of apoptosis was observed. Gene ontology revealed unique dysregulated biological process related to neuronal differentiation and mesoderm development. Pathway analysis showed the axon guidance pathway to be dysregulated.CONCLUSIONS AND IMPLICATIONS Our results suggest that hESCs in combination with toxicogenomics offer a sensitive in vitro developmental toxicity model as an alternative to traditional animal experiments.
The Beta Dilemma in Emerging Markets
Authors: Pereiro Luis E. 
Published: December 2010

In principle, emerging markets analysts employ the same analytical framework when estimating the value of businesses as their counterparts in developed economies: they forecast future cash flows and discount those to the present with appropriate costs of capital that are estimated using the Capital Asset Pricing Model (CAPM) framework.But in practice, emerging market analysts have a more complicated job because the task of estimating costs of equity in emerging markets is more difficult. Whereas developed economies have an abundance of historical data on overall stock market movements, industry share price behavior, and many individual share price histories, emerging market economies often do not. There may be no comparable local firms that are publicly traded—or if there are, their CAPM betas may be unreliable. And if analysts instead use the beta of a U.S. competitor as a surrogate for the emerging market beta, they face the question of whether domestic betas are equivalent across borders.As a consequence, appraisers of emerging market companies confront a “beta dilemma.” Part of this is a data problem stemming from shorter share price histories in emerging markets and the absence of publicly traded companies in some industries. In such cases, analysts may be inclined to use industry betas calculated with U.S. share prices as a substitute. But this creates an equivalence problem—the possibility, as confirmed by the author's research, that domestic U.S. and emerging market betas are not statistically equivalent for most industries. The author proposes a solution to this problem that involves grouping emerging markets into a single, distinctive asset class that allows for reliable calculations of industry betas. He also suggests ways of testing emerging market industry betas to determine whether they are statistically comparable.
High Temperature Strain Structures and Quartz C‐Axis Fabrics from Mylonitic Rocks in the Ailaoshan‐Red River Shear Zone, Yunnan, and Their Tectonic Implication
Authors: Junlai LIU , Yuan TANG , Haoran XIA , Qiang GUO , Dung TRAN My , Shuyun CAO , Hujun WU , Wenbin WU , Zhaochong ZHANG , Zhidan ZHAO 
Published: December 2010

Abstract:The Ailaoshan‐Red River (ASRR) shear zone is one of the major Southeast Asian tectonic discontinuities that have figured the present tectonic framework of the eastern Tibet. Several metamorphic massifs are distributed linearly along the shear zone, e.g. Xuelongshan, Diancangshan, Ailaoshan and Day Nui Con Voi from north to south. They bear a lot of lines of evidence for the tectonic evolution of the eastern Tibetan at different crustal levels in different tectonic stages. Controversy still exists on the deformation structures, microstructures and their relationship with metamorphisms along the ASRR. In this paper detailed microstructural and EBSD (Electron Backscattered Diffraction) fabric analysis of some highly sheared granitic rocks from different massifs along the ASRR are conducted. High temperature structures and microstructures are preserved in unsheared gneisses, in weakly sheared xenoliths or in some parts of the highly sheared rocks (mylonites). Several types of high temperature quartz c‐axis fabrics show symmetrical patterns or transitions from symmetrical to asymmetrical patterns. The former are attributed to coaxial deformation during regional shortening in an early stage of the Indian‐Eurasian tectonic interaction and the latter are related to the transitions from coaxial compression to noncoaxial shearing during the post‐collisional ASRR left lateral shearing.
Influence of the Chuxiong Yao'an Earthquake on the Mineralization of Hot Springs in the Tengchong Geothermal Area, Southwestern China
Authors: Jun DENG , Changhao XIAO , Qingfei WANG , Xingzhi ZHOU , Liqiang YANG , Jing ZHANG , Yan ZHAO 
Published: December 2010

Abstract:The Tengchong geothermal area, an active tectonic region with frequent earthquakes, is located in Yunnan Province of southwestern China. This area contains abundant active hot springs, which often display high metal concentrations and obvious mineralization phenomena. At 19:19 on 9 July 2009, an earthquake occurred in Yao'an, Chuxiong, Yunnan Province, which is 300 km to the northeast of the Tengchong geothermal area. We sampled water in the hot springs in the Tengchong area from 4 July to 9 July 2009 and from 10 July to 15 July 2009 to study the changes of elemental concentrations before and after the earthquake and discuss the influence of the earthquake on the mineralization of the hot springs. The concentrations of most trace elements increased slightly, but the concentration of REE (rare earth elements) decreased by 50% after the earthquake in the hot springs around a NS‐trending fault. The elemental concentrations remained unchanged in Longtan and Suanshuigou, which are related to an inactive crater. The elemental concentrations in other springs controlled by superficial and small‐scale faults decreased after the earthquake. The earthquake can stimulate the activity of deep faults and magma chambers, as is responsible for the increase of metal concentrations in the hot springs along the NS‐trending deep fault; whereas it can decrease the porosity of permeable rocks, resulting in the decline of the flux of ore‐bearing fluids and the corresponding mineralization in the hot springs related to superficial faults.
Comparison of Ki67 and modified AgNOR in dysplastic epithelial lesion, primary squamous cell carcinoma and metastatic squamous cell carcinoma of head and neck
Authors: Ashraf Mohamad Javad , Azarpira Negar , Safarzadegan Zahra , Tadbir Azadeh Andisheh , Khademi Bighan 
Published: December 2010

ABSTRACTThe variations in nucleolar organizer regions (AgNOR) and the increase in Ki67 expression and correlation with histological findings in 64 specimen squamous epithelium from normal epithelium to overt carcinoma were evaluated. Mean AgNOR counts (mAgNOR), proliferative index (pAgNOR), variation in size and dispersion of AgNOR dots in cells were graded and compared in normal, dysplastic, primary and metastatic squamous cell carcinoma (SCC). The Ki67 percentage is significantly increased from normal squamous to SCC group, and the reactivity of staining were related to histological differentiation. The mAgNOR counts were high in all 44 cases of primary and metastatic SCC and low in normal squamous tissue and increased in dysplastic lesions. The mAgNOR count in SCC increased from well differentiated to poorly differentiated. PAgNOR counts were gradually increased in different grade of SCC, 1.4% in well differentiated, 6% in moderately differentiated, 19% in poorly differentiated. There was only significant difference between well differentiated versus poorly differentiated cases. Only significant correlation between Ki67 percentage and mAgNOR and between Ki67 percentage and pAgNOR in primary SCC group was noticed. Therefore, Ki67 is gold standard method for evaluation of proliferation activity. AgNOR quantity is proportional to the proliferative activity of the cell but does not necessarily indicate malignancy.
Improving Urban Stormwater Quality: Applying Fundamental Principles
Authors: Davis Allen P. , Traver Robert G. , Hunt William F. 
Published: December 2010

Abstract:Urban stormwater runoff is a growing contributor to the impairment of surface waters. Nature‐based technologies, including green roofs, vegetated swales, grassed filter strips, bioretention, and pervious pavements have been demonstrated to be effective in mitigating detrimental runoff characteristics. Lacking, however, has been a fundamental engineering analysis approach to these technologies. Current design guidance is based on empirical recommendations and most performance data are based on limited, localized observations. Flow balances, including infiltration, evapotranspiration and surface discharge, based on fundamental fluid dynamics principles can be employed through analysis to understand flow management. Water quality improvements will occur through a specific unit processes or mechanisms, including sedimentation, filtration, adsorption, biotransformation, bio‐uptake, and heat transfer. The performance of a specific technology will depend on the facility configuration and makeup, climate, surrounding soil characteristics, topography, and the site hydrology. Applying fundamental flow and water quality processes to storm water management technologies will allow quantitative design and predictable performance characterization.
Best Management Practices for Stormwater Management in the Desert Southwest
Authors: Gautam Mahesh R. , Acharya Kumud , Stone Mark 
Published: December 2010

Abstract:Despite several decades of experience with stormwater Best Management Practices (BMPs) in the United States, the application of such approaches in the Desert Southwest region has not received adequate attention. One reason for this shortcoming could be the general perception of the insignificance of BMPs in a region with little annual precipitation. However, the Desert Southwest still experiences relatively high rainfall intensity and runoff from rainfall. Sparse vegetation, steep topography, complex soils, unique geology, and rapid land development all contribute increase runoff response. Since the Desert Southwest hosts a large and rapidly growing population, stormwater BMPs are important for protecting the quality and quantity of scarce receiving surface and ground waters. The hydrometereological characteristics of intense short‐term precipitation, large inter‐storm duration, and smaller annual volumes of rainfall and the region's watershed characteristics are unique; the design of regional stormwater BMPs should consider these characteristics. Also, there is a need for more specific design guidance for implementing general approaches for adapting stormwater BMPs from humid regions to arid settings.
Survey Says: Implications of a Public Perception Survey on Stormwater Education Programming
Authors: Giacalone Katie , Mobley Catherine , Sawyer Calvin , Witte Jim , Eidson Gene 
Published: December 2010

Abstract:Effective watershed and stormwater education and public involvement programs strive to increase awareness of watersheds and landscape connectivity and also encourage behavior changes that may be contributing to water quality and quantity problems within a targeted basin. According to new guidance from the US Environmental Protection Agency on stormwater permit improvement, regulators are looking for programs to utilize targeted issues relevant to a community to guide the development of a comprehensive outreach program. In an effort to collect information on public perception, knowledge, behaviors and willingness to get involved in improved stormwater management, a telephone survey was implemented. This manuscript presents the results of this survey and offers insight on stakeholders’ attitudes, knowledge, and behaviors related to watershed and stormwater, critical factors in the initial development of effective stormwater education and public involvement programs.
The Tolerance of the Frontal Bone to Blunt Impact
Authors: Cormier Joseph , Manoogian Sarah , Bisplinghoff Jill , Rowson Steve , Santago Anthony , McNally Craig , Duma Stefan , Bolte John 
Published: December 2010

AbstractThe current understanding of the tolerance of the frontal bone to blunt impact is limited. Previous studies have utilized vastly different methods, which limits the use of statistical analyses to determine the tolerance of the frontal bone. The purpose of this study is to determine the tolerance of the frontal bone to blunt impact. Acoustic emission sensors were used to provide a noncensored measure of the frontal bone tolerance and were essential due to the increase in impactor force after fracture onset. In this study, risk functions for fracture were developed using parametric and nonparametric techniques. The results of the statistical analyses suggest that a 50% risk of frontal bone fracture occurs at a force between 1885 N and 2405 N. Subjects that were found to have a frontal sinus present within the impacted region had a significantly higher risk of sustaining a fracture. There was no association between subject age and fracture force. The results of the current study suggest that utilizing peak force as an estimate of fracture tolerance will overestimate the force necessary to create a frontal bone fracture.
Identification, Diagnostic Potential, and Natural Expression of Immunodominant Seroreactive Peptides Encoded by Five
Mycobacterium tuberculosis
-Specific Genomic Regions
Authors: Al-Khodari Noora Y. , Al-Attiyah Rajaa , Mustafa Abu S. 
Published: December 2010

ABSTRACT

Comparative genomic studies have identified several
Mycobacterium tuberculosis
-specific genomic regions of difference (RDs) which are absent in the vaccine strains of
Mycobacterium bovis
BCG and which may be useful in the specific diagnosis of tuberculosis (TB). In this study, a total of 775 synthetic peptides covering the sequences of 39 open reading frame (ORF) proteins encoded by genes predicted in five RDs of
M. tuberculosis
, i.e., RD1, RD4, RD5, RD6, and RD7, were tested by enzyme-linked immunosorbent assays for antibody reactivity with sera from HIV-negative pulmonary TB patients (
n
= 100) and
M. bovis
BCG-vaccinated healthy subjects (
n
= 100). The results identified three immunodominant peptides reactive with TB sera, i.e., amino acids (aa) 346 to 370 of RD1ORF Rv3876, aa 241 to 265 of RD6ORF Rv1508c, and aa 325 to 336 of RD6ORF Rv1516c. These peptides had significantly stronger antibody reactivity with sera from TB patients than with sera from healthy subjects (
P
< 0.05) and significantly higher rates of positivity with TB sera (positives = 66 to 93%) than sera from healthy subjects (positives = 10 to 28%). Antipeptide antibodies were raised in rabbits after immunization with pools of 11 peptides corresponding to each protein. Probing of culture filtrates and whole-cell lysates of
M. tuberculosis
with antipeptide antibodies suggested the natural expression of Rv1516c in whole-cell lysates of
M. tuberculosis
. The results suggest the potential of the identified immunodominant RD peptides in the serodiagnosis of TB.
Decreased Serum Antibody Responses to Recombinant
Pneumocystis
Antigens in HIV-Infected and Uninfected Current Smokers
Authors: Crothers Kristina , Daly Kieran R. , Rimland David , Goetz Matthew Bidwell , Gibert Cynthia L. , Butt Adeel A. , Justice Amy C. , Djawe Kpandja , Levin Linda , Walzer Peter D. 
Published: December 2010

ABSTRACT

Serologic studies can provide important insights into the epidemiology and transmission of
Pneumocystis jirovecii
. Exposure to
P. jirovecii
can be assessed by serum antibody responses to recombinant antigens from the major surface glycoprotein (MsgC), although factors that influence the magnitude of the antibody response are incompletely understood. We determined the magnitudes of antibody responses to
P. jirovecii
in comparison to adenovirus and respiratory syncytial virus (RSV) in HIV-infected and uninfected patients and identified predictors associated with the magnitude of the response. We performed a cross-sectional analysis using serum samples and data from 153 HIV-positive and 92 HIV-negative subjects enrolled in a feasibility study of the Veterans Aging Cohort 5 Site Study (VACS 5). Antibodies were measured using an enzyme-linked immunosorbent assay (ELISA). Independent predictors of antibody responses were determined using multivariate Tobit regression models. The results showed that serum antibody responses to
P. jirovecii
MsgC fragments were significantly and independently decreased in current smokers. Antibodies to
P. jirovecii
also tended to be lower with chronic obstructive pulmonary disease (COPD), hazardous alcohol use, injection drug use, and HIV infection, although these results were not statistically significant. These results were specific to
P. jirovecii
and did not correlate with adenovirus. Antibody responses to RSV were in the inverse direction. Thus, current smoking was independently associated with decreased
P. jirovecii
antibody responses. Whether smoking exerts an immunosuppressive effect that affects the
P. jirovecii
antibody response, colonization, or subsequent risk for disease is unclear; prospective, longitudinal studies are needed to evaluate these findings further.
Clonal Diversity of Nosocomial Epidemic Acinetobacter baumannii Strains Isolated in Spain
Authors: Villalón Pilar , Valdezate Sylvia , Medina-Pascual Maria J. , Rubio Virginia , Vindel Ana , Saez-Nieto Juan A. 
Published: December 2010

ABSTRACT

Acinetobacter baumannii
is one of the major pathogens involved in nosocomial outbreaks. The clonal diversity of 729 epidemic strains isolated from 19 Spanish hospitals (mainly from intensive care units) was analyzed over an 11-year period. Pulsed-field gel electrophoresis (PFGE) identified 58 PFGE types that were subjected to susceptibility testing,
rpoB
gene sequencing, and multilocus sequence typing (MLST). All PFGE types were multidrug resistant; colistin was the only agent to which all pathogens were susceptible. The 58 PFGE types were grouped into 16 clones based on their genetic similarity (cutoff of 80%). These clones were distributed into one major cluster (cluster D), three medium clusters (clusters A, B, and C), and three minor clusters (clusters E, F, and G). The
rpoB
gene sequencing and MLST results reflected a clonal distribution, in agreement with the PFGE results. The MLST sequence types (STs) (and their percent distributions) were as follows: ST-2 (47.5%), ST-3 (5.1%), ST-15 (1.7%), ST-32 (1.7%), ST-79 (13.6%), ST-80 (20.3%), and ST-81 (10.2%). ST-79, ST-80, and ST-81 and the alleles
cpn60-26
and
recA29
are described for the first time. International clones I, II, and III were represented by ST-81, ST-2, and ST-3, respectively. ST-79 and ST-80 could be novel emerging clones. This work confirms PFGE and MLST to be complementary tools in clonality studies. Here PFGE was able to demonstrate the monoclonal pattern of most outbreaks, the inter- and intrahospital transmission of bacteria, and their endemic persistence in some wards. MLST allowed the temporal evolution and spatial distribution of Spanish clones to be monitored and permitted international comparisons to be made.
Clostridium difficile Colonization in Early Infancy Is Accompanied by Changes in Intestinal Microbiota Composition
Authors: Rousseau Clotilde , Levenez Florence , Fouqueray Charlène , Doré Joël , Collignon Anne , Lepage Patricia 
Published: December 2010

ABSTRACT

Clostridium difficile
is a major enteric pathogen responsible for antibiotic-associated diarrhea. Host susceptibility to
C. difficile
infections results partly from inability of the intestinal microbiota to resist
C. difficile
colonization. During early infancy, asymptomatic colonization by
C. difficile
is common and the intestinal microbiota shows low complexity. Thus, we investigated the potential relationship between the microbiota composition and the implantation of
C. difficile
in infant gut. Fecal samples from 53 infants, ages 0 to 13 months, 27 negative and 26 positive for
C. difficile
, were studied. Dominant microbiota profiles were assessed by PCR-temporal temperature gradient gel electrophoresis (TTGE). Bacterial signatures of the intestinal microbiota associated with colonization by
C. difficile
were deciphered using principal component analysis (PCA). Resulting bands of interest in TTGE profiles were excised, sequenced, and analyzed by nucleotide BLAST (NCBI). While global biodiversity was not affected, interclass PCA on instrumental variables highlighted significant differences in dominant bacterial species between
C. difficile
-colonized and noncolonized infants (
P
= 0.017). Four bands were specifically associated with the presence or absence of
C. difficile
: 16S rRNA gene sequences related to
Ruminococcus gnavus
and
Klebsiella pneumoniae
for colonized infants and to
Bifidobacterium longum
for noncolonized infants. We demonstrated that the presence of
C. difficile
in the intestinal microbiota of infants was associated with changes in this ecosystem's composition. These results suggest that the composition of the gut microbiota might be crucial in the colonization process, although the chronology of events remains to be determined.