bluuebunny/crossref_metadata_2025_split huggingface dataset:
Drosophila female sterile (1) homeotic is a multifunctional transcriptional regulator that is modulated by Ras signaling
Authors: Florence Brian L. , Faller Douglas V. 
Published: February 2008

AbstractThe Drosophila (fs(1)h) gene encodes small (Fs(1)hS) and large (Fs(1)hL) chromatin‐binding BET protein transcription factor isoforms. Zygotic mutations cause either lethality or female sterility, whereas maternal mutations cause segmental deletions and thoracic homeotic transformations. Here, we describe novel fs(1)h embryonic phenotypes: homeosis of the head in zygotic mutants and deletion of head and tail regions in maternal mutants, similar to those caused by dominant torso (torD) alleles. tor activates transcription of tailless (tll) and hückebein (hkb) by means of a canonical Ras pathway, through inactivation of Groucho (Gro), Capicua (Cic) and, possibly, Grainy‐head (Grh) repressors. Expression of both tailless and hückebein are de‐repressed in fs(1)h maternal mutants, as in torD, gro, grh, and cic mutant animals, indicating fs(1)h is also necessary for tll and hkb repression. These data link Ras signaling with modulation of a chromatin‐binding transcription factor, Fs(1)h, suggesting a novel mechanism by which Ras can modulate gene expression. Developmental Dynamics 237:554–564, 2008. © 2008 Wiley‐Liss, Inc.
Molecular evolution and expression of zebrafish St8SiaIII, an alpha‐2,8‐sialyltransferase involved in myotome development
Authors: Bentrop Joachim , Marx Monika , Schattschneider Sebastian , Rivera‐Milla Eric , Bastmeyer Martin 
Published: February 2008

AbstractEnzymes of the St8Sia family, a subgroup of the glycosyltransferases, mediate the transfer of sialic acid to glycoproteins or glycolipids. Here, we describe the cloning of the zebrafish St8SiaIII gene and study its developmental activity. A conserved synteny relationship among vertebrate chromosome regions containing St8SiaIII loci underscores an ancient duplication of this gene in the teleost fish lineage and a specific secondary loss of one paralog in the zebrafish. The single zebrafish St8SiaIII enzyme, which is expected to function as an oligosialyltransferase, lacks maternal activity, is weakly expressed during nervous system development, and shows a highly dynamic expression pattern in somites and somite‐derived structures. Morpholino knock‐down of St8SiaIII leads to anomalous somite morphologies, including defects in segment boundary formation and myotendious‐junction integrity. These phenotypes hint for a basic activity of zebrafish St8SiaIII during segmentation and somite formation, providing novel evidence for a non‐neuronal function of sialyltransferases during vertebrate development. Developmental Dynamics 237:808–818, 2008. © 2008 Wiley‐Liss, Inc.
Activin/nodal signaling modulates XPAPC expression during Xenopus gastrulation
Authors: Lou Xin , Li Shuangwei , Wang Jinhu , Ding Xiaoyan 
Published: February 2008

AbstractGastrulation is the first obligatory morphogenesis during vertebrate development, by which the body plan is established. Nodal signaling is a key player in many developmental processes, including gastrulation. XPAPC has been found to exert its biological function through modifying the adhesion property of cells and interacting with other several important molecules in embryos. In this report, we show that nodal signaling is necessary and sufficient for XPAPC expression during Xenopus gastrulation. Furthermore, we isolated 4.8 kb upstream DNA sequence of Xenopus XPAPC, and proved that this 4.8‐kb genomic contig is sufficient to recapitulate the expression pattern of XPAPC from gastrula to tail bud stage. Transgene and ChIP assays indicate that Activin/nodal signaling participates in regulation of XPAPC expression through a Smad binding element within the XPAPC promoter. Concomitant investigation suggests that the canonical Wnt pathway‐activated XPAPC expression requires nodal signaling. Developmental Dynamics 237:683–691, 2008. © 2008 Wiley‐Liss, Inc.
Dynamics of zebrafish somitogenesis
Authors: Schröter Christian , Herrgen Leah , Cardona Albert , Brouhard Gary J. , Feldman Benjamin , Oates Andrew C. 
Published: February 2008

AbstractVertebrate somitogenesis is a rhythmically repeated morphogenetic process. The dependence of somitogenesis dynamics on axial position and temperature has not been investigated systematically in any species. Here we use multiple embryo time‐lapse imaging to precisely estimate somitogenesis period and somite length under various conditions in the zebrafish embryo. Somites form at a constant period along the trunk, but the period gradually increases in the tail. Somite length varies along the axis in a stereotypical manner, with tail somites decreasing in size. Therefore, our measurements prompt important modifications to the steady‐state Clock and Wavefront model: somitogenesis period, somite length, and wavefront velocity all change with axial position. Finally, we show that somitogenesis period changes more than threefold across the standard developmental temperature range, whereas the axial somite length distribution is temperature invariant. This finding indicates that the temperature‐induced change in somitogenesis period exactly compensates for altered axial growth. Developmental Dynamics 237:545–553, 2008. © 2008 Wiley‐Liss, Inc.
Characterization and comparative expression of zebrafish calpain system genes during early development
Authors: Lepage Stephanie E. , Bruce Ashley E.E. 
Published: February 2008

AbstractThe classic calpain system has been implicated in regulating a variety of cellular processes including cell adhesion, migration, and intracellular signaling; however, little is known regarding the function of this system in vivo. Two heterodimeric Ca2+‐dependent cysteine proteases, μ‐calpain (CAPN1) and m‐calpain (CAPN2), and the endogenous inhibitor calpastatin (CAST) comprise the classic/ubiquitous calpain system in mammals. Recently, knockout of two murine classic calpain genes, Capn2 and Capn4/Capns1, revealed that components of the classic system are indispensable for preimplantation development. We identified four classic calpain catalytic subunit genes (capn1a, 1b, 2a, 2b), two regulatory subunit genes (capns1a, 1b), and calpastatin (cast) from the zebrafish. Our data suggest that the components of the classic mammalian system are both conserved and expanded in the teleost lineage. In contrast to the classic/ubiquitous mammalian system, zebrafish calpain system genes acquire unique, tissue‐specific patterns of expression within the first 2 days of development. Developmental Dynamics 237:819–829, 2008. © 2008 Wiley‐Liss, Inc.
Cardiac malformations and myocardial abnormalities in podoplanin knockout mouse embryos: Correlation with abnormal epicardial development
Authors: Mahtab Edris A.F. , Wijffels Maurits C.E.F. , Van Den Akker Nynke M.S. , Hahurij Nathan D. , Lie‐Venema Heleen , Wisse Lambertus J. , DeRuiter Marco C. , Uhrin Pavel , Zaujec Jan , Binder Bernd R. , Schalij Martin J. , Poelmann Robert E. , Gittenberger‐De Groot Adriana C. 
Published: February 2008

AbstractEpicardium and epicardium‐derived cells have been shown to be necessary for myocardial differentiation. To elucidate the function of podoplanin in epicardial development and myocardial differentiation, we analyzed podoplanin knockout mouse embryos between embryonic day (E) 9.5 and E15.5 using immunohistochemical differentiation markers, morphometry, and three‐dimensional reconstructions. Podoplanin null mice have an increased embryonic lethality, possibly of cardiac origin. Our study reveals impairment in the development of the proepicardial organ, epicardial adhesion, and spreading and migration of the epicardium‐derived cells. Mutant embryos show a hypoplastic and perforated compact and septal myocardium, hypoplastic atrioventricular cushions resulting in atrioventricular valve abnormalities, as well as coronary artery abnormalities. The epicardial pathology is correlated with reduced epithelial–mesenchymal transformation caused by up‐regulation of E‐cadherin, normally down‐regulated by podoplanin. Our results demonstrate a role for podoplanin in normal cardiac development based on epicardial–myocardial interaction. Abnormal epicardial differentiation and reduced epithelial–mesenchymal transformation result in deficient epicardium‐derived cells leading to myocardial pathology and cardiac anomalies. Developmental Dynamics 237:847–857, 2008. © 2008 Wiley‐Liss, Inc.
mTOR signaling contributes to chondrocyte differentiation
Authors: Phornphutkul Chanika , Wu Ke‐Ying , Auyeung Valerie , Chen Qian , Gruppuso Philip A. 
Published: February 2008

AbstractThe mammalian Target Of Rapamycin (mTOR) is a nutrient‐sensing protein kinase that regulates numerous cellular processes. Fetal rat metatarsal explants were used as a physiological model to study the effect of mTOR inhibition on chondrogenesis. Insulin significantly enhanced their growth. Rapamycin significantly diminished this response to insulin through a selective effect on the hypertrophic zone. Cell proliferation (bromodeoxyuridine incorporation) was unaffected by rapamycin. Similar observations were made when rapamycin was injected to embryonic day (E) 19 fetal rats in situ. In the ATDC5 chondrogenic cell line, rapamycin inhibited proteoglycan accumulation and collagen X expression. Rapamycin decreased content of Indian Hedgehog (Ihh), a regulator of chondrocyte differentiation. Addition of Ihh to culture medium reversed the effect of rapamycin. We conclude that modulation of mTOR signaling contributes to chondrocyte differentiation, perhaps through its ability to regulate Ihh. Our findings support the hypothesis that nutrients, acting through mTOR, directly influence chondrocyte differentiation and long bone growth. Developmental Dynamics 237:702–712, 2008. © 2008 Wiley‐Liss, Inc.
Nanocomposites: From Fabrications to Electrochemical Bioapplications
Authors: Xiao Yinghong , Li Chang Ming 
Published: February 2008

AbstractNanostructured materials including nanoparticles, nanowires, nanobands and carbon nanotubes (CNT) have been intensively investigated due to their fantastic ‘size effect’ and superior chemical and physical properties and functions. Nanocomposites can be fabricated not only with different nanostructured materials, but also with various biomolecules and conducting polymers to possess unique hybrid properties characteristic of neither the incorporated components nor the host matrices. The nanocomposites may be confined in nanoscale domains in one, two, or three dimensions for the unusual size‐dependent behavior. The synergistic effects of the components lead to broad bioapplications of the nanocomposites such as biosensors, drug delivery systems and biofuel cells. A review of studies on nanocomposites from design, fabrication to their biocompatibility and electrochemical bioapplications is presented.
Assessment of chromosomal gains as compared to DNA content changes is more useful to detect dysplasia in Barrett's esophagus brush cytology specimens
Authors: Rygiel Agnieszka M. , Milano Francesca , ten Kate Febo J. , de Groot John G. , Peppelenbosch Maikel P. , Bergman Jacques J. G. H. M. , Krishnadath Kauslillia K. 
Published: February 2008

AbstractAbnormal DNA ploidy status has been suggested as a prognostic factor for Barrett's esophagus progression into esophageal adenocarcinoma (EAC). The aim of the study was to compare image cytometry DNA analysis (ICDA) and fluorescent in situ hybridization (FISH) in the assessment of DNA ploidy status in Barrett's esophagus (BE), and to determine the value of these abnormalities as an adjunct to conventional cytology in detection of dysplasia and EAC. Brush cytology specimens of 90 BE patients were examined using ICDA and FISH with peri‐centromeric probes for chromosomes 7 and 17. The results of ICDA and FISH were compared with each other, and with dysplasia grade or EAC as determined by histology and cytology. FISH and ICDA detected abnormalities in 41% (37/90) and 22% (19/90) of the BE cases, respectively. Gains of chromosome 7 and/or 17 were present in 13% of nondysplasia cases, which further increased with dysplasia stage, while overall DNA content aneuploidy was detected predominantly in high grade dysplasia (HGD) and EAC. Using FISH results combined with cytology, we were able to identify IND/LGD (indefinite/ low grade dysplasia) with a sensitivity and specificity of 75 and 76%, respectively. FISH alone detected HGD/EAC with a high sensitivity and specificity of 85 and 84%, which was superior to that of cytology alone. Thus, FISH is more sensitive than ICDA to detect chromosomal abnormalities in BE brush cytology specimens. FISH detects chromosomal gains in early stages of BE and represents a valuable adjunct to conventional cytology to detect dysplasia or EAC. © 2008 Wiley‐Liss, Inc.
Times of Change in Omani Oases
Authors: Bürkert Andreas , Hammer Karl , Schlecht Eva , Häser Jutta , Al Khanjari Sulaiman 
Published: February 2008

AbstractFor millennia, highly developed oasis farming, alongside fishing, has formed the basis of life for the sedentary people of Oman. Researchers take a deeper look at the changing land use strategies in remote mountain oasis settlements
Estimating production costs in the economic evaluation of health‐care programs
Authors: Herrero Carmen , Moreno‐Ternero Juan D. 
Published: February 2008

AbstractWe propose a method for calculating the production costs of an intervention in a manner that accounts for differences in productive ‘effort.’ This method could be used within a cost‐effectiveness analysis framework in the evaluation of new medical technologies, pharmaceuticals, treatment programs, or public health interventions. We apply it to show evidence in favor of implementing a newborn screening program to detect congenital hearing impairment. Copyright © 2008 John Wiley & Sons, Ltd.
Thermal pollution of streams by runoff from paved surfaces
Authors: Herb William R. , Janke Ben , Mohseni Omid , Stefan Heinz G. 
Published: February 2008

AbstractUrban development dramatically alters a drainage system by landscaping, changes in surface cover, and addition of stormwater handling systems. Increased and warmer runoff from impervious surfaces into streams can lead to a degradation of habitat for coldwater fish. For the projection of thermal impacts of new land development projects, hydro‐thermal simulation models have been developed. With measured climate as input, these deterministic models can be used to predict the thermal impact of individual storm events. Surface runoff and runoff temperature were simulated for an asphalt parking lot using 6 years of climate data from Minnesota, USA, with 282 individual rainfall events. The thermal loading from each rainfall event was quantified by three parameters: runoff temperature ( °C), rate of heat export (W/m2) and total (integral) heat export (J/m2). Many storm events were found to have little thermal impact, but a few events per year have high thermal impact, either due to large rainfall amounts at a high dew point temperature or due to high land surface temperature combined with moderate rainfall amounts. The amount of heat added to the runoff is highly dependent on both the characteristics of the rainfall event and the weather conditions prior to the storm event. Runoff temperatures from asphalt were found to be well correlated to a linear combination of three parameters: average dew point temperature during the storm, air temperature prior to the storm, and solar radiation prior to the storm. The study results imply that stormwater thermal pollution is more severe when (1) atmospheric air and dew point temperatures are higher than stream temperature, e.g. for streams that are fed by groundwater that is colder than the ambient air, (2) rainfall events are short, intense and preceded by full or partial sun, and (3) watersheds have a high percentage of impervious, particular paved, surfaces. Copyright © 2008 John Wiley & Sons, Ltd.
Transient receptor potential vanilloid 4 deficiency suppresses unloading‐induced bone loss
Authors: Mizoguchi Fumitaka , Mizuno Atsuko , Hayata Tadayoshi , Nakashima Kazuhisa , Heller Stefan , Ushida Takashi , Sokabe Masahiro , Miyasaka Nobuyuki , Suzuki Makoto , Ezura Yoichi , Noda Masaki 
Published: February 2008

AbstractMechanosensing is one of the crucial components of the biological events. In bone, as observed in unloading‐induced osteoporosis in bed ridden patients, mechanical stress determines the levels of bone mass. Many molecules have been suggested to be involved in sensing mechanical stress in bone, while the full pathways for this event has not yet been identified. We examined the role of TRPV4 in unloading‐induced bone loss. Hind limb unloading induced osteopenia in wild‐type mice. In contrast, TRPV4 deficiency suppressed such unloading‐induced bone loss. As underlying mechanism for such effects, TRPV4 deficiency suppressed unloading‐induced reduction in the levels of mineral apposition rate and bone formation rate. In these mice, unloading‐induced increase in the number of osteoclasts in the primary trabecular bone was suppressed by TRPV4 deficiency. Unloading‐induced reduction in the longitudinal length of primary trabecular bone was also suppressed by TRPV4 deficiency. TRPV4 protein is expressed in both osteoblasts and osteoclasts. These results indicated that TRPV4 plays a critical role in unloading‐induced bone loss. J. Cell. Physiol. 216: 47–53, 2008. © 2008 Wiley‐Liss, Inc.
Using dynamic tests to study the continuous mixing of xanthan gum solutions
Authors: Saeed Salwan , Ein‐Mozaffari Farhad 
Published: February 2008

AbstractBACKGROUND:The current understanding and implementation of continuous mixing of non‐Newtonian fluids is insufficient to ensure good mixing in many cases. In this study, the dynamic response of the continuous mixing of xanthan gum solution, which is a pseudoplastic fluid with yield stress, was quantified using a dynamic model that incorporated non‐ideal flows within the mixing vessel. The model allowed for two parallel flow paths through the tank: (1) a channeling zone and (2) a mixing zone.RESULTS:Dynamic tests were made using the frequency‐modulated random binary input of a brine solution with the feed to determine the magnitude of non‐ideal flows. The extent of flow bypassing the mixing zone and the effective mixed volume were determined from dynamic tests and used as mixing quality criteria. We explored the effect of impeller speed, impeller type, feed flow rate through the mixing tank, fluid rheology, and feed and exit location on the degree of channeling and the fraction of fully mixed volume. Tests show that when the surface of the cavern created by impeller approaches the tank wall, the bottom of the tank, and the surface of the fluid within the mixing vessel, the percentage of non‐ideal flow approached zero.CONCLUSION:This study identifies important criteria for continuous mixing vessels that will improve mixing efficiency. By applying these findings, a reduction in the extent of non‐ideal flow can be achieved, which will improve the quality and control of the continuous mixing processes such as continuous high‐viscosity reactor, continuous fermenter, and continuous solid–liquid mixing. Copyright © 2008 Society of Chemical Industry
Effects of sodium chloride on the production of bioactive exopolysaccharides in submerged cultures of Phellinus linteus
Authors: Shu Chin‐Hang , Hsu Hui‐Ju 
Published: February 2008

AbstractBACKGROUND: Polysaccharides isolated from medicinal mushrooms have been shown to exhibit antitumour bioactivity, but the quality and quantity of these polysaccharides are affected by variations in medium composition and operational conditions in the submerged culture. This study was conducted to elucidate quantitatively the effects of sodium chloride (NaCl) supplementation on the production and quality of exopolysaccharides from the medicinal mushroom Phellinus linteus.RESULTS: Supplementation of NaCl to submerged cultures of P. linteus significantly affected the morphology, the exopolysaccharide (PLPS) production, its average molecular weight and its biological activity. Phellinus linteus grew in a filamentous form in NaCl‐free medium, but a pellet form became predominant as NaCl supplemention increased. The specific growth rate decreased monotonically from 0.18 to 0.01 day−1 as the NaCl concentration increased from 0.0 to 2.0 g dm−3 (34.22 mmol dm−3); however, the specific product yield increased monotonically from 3.9 to 98.4 mg g−1 (25.2‐fold enhancement). Both 14.3‐fold enhancement (from 23 to 329 mg dm−3) in the production of PLPS and 1.5‐fold enhancement (from 670 to 995 pg TNF‐α (tumour necrosis factor α) cm−3) in its biological activity were achieved as the NaCl concentration increased from 0.0 to 1.0 g dm−3 (17.11 mmol dm−3). The biological activity of PLPS was highly correlated with its average molecular weight (coefficient R2 = 0.90).CONCLUSION: The average molecular weight of PLPS was key to its biological activity. Both the quantity and bioactivity of PLPS could be significantly enhanced by appropriate NaCl supplementation to the submerged culture of the medicinal mushroom. Copyright © 2008 Society of Chemical Industry
Synthesis of ethylene carbonate from urea and ethylene glycol over zinc/iron oxide catalyst
Authors: Zhao Xinqiang , An Hualiang , Wang Shufang , Li Fang , Wang Yanji 
Published: February 2008

AbstractBACKGROUND: Ethylene carbonate (EC) was synthesised via urea and ethylene glycol (EG) over zinc/iron oxide catalyst. By so doing, the by‐product, EG, generated in the process of producing dimethyl carbonate by the transesterification route was converted back to the raw material, EC. The reaction mechanism of EC synthesis was also investigated by means of gas chromatography/mass spectrometry and in situ Fourier transform infrared/attenuated total reflection spectroscopy.RESULTS: Suitable conditions for the preparation of zinc/iron oxide catalyst were as follows: zinc acetate and iron nitrate as precursors, Zn/Fe molar ratio 8:1, calcination temperature 350 °C and calcination time 4 h. Characterisation by X‐ray diffraction revealed two different crystal phases: ZnO and ZnFe2O4. The highest yield of EC (66.1%) was obtained under the following conditions: reaction temperature 150 °C, reaction time 2.5 h, catalyst weight percentage 1.5% and urea/EG molar ratio 1:8. The study of the reaction mechanism revealed that the reaction for the synthesis of EC proceeded in two steps.CONCLUSION: The synergistic effect of ZnO and ZnFe2O4 promoted the catalytic performance of zinc/iron oxide. Copyright © 2008 Society of Chemical Industry