bluuebunny/crossref_metadata_2025 huggingface dataset:
Obesity in Asia – is it different from rest of the world
Authors: Ramachandran Ambady , Chamukuttan Snehalatha , Shetty Samith A. , Arun Nanditha , Susairaj Priscilla
Published: December 2012

An epidemic of obesity and obesity related diseases such as diabetes and cardio vascular disease (CVD) is prevalent in many Asian countries. Migration from rural to urban areas, and rapid socio‐economic transition are associated with the lifestyle changes resulting in decreased levels of physical activity and increased intake of energy dense diet.
Prevention of diabetes: a strategic approach for individual patients
Authors: Shin Jeong‐Ah , Lee Jin‐Hee , Kim Hun‐Sung , Choi Yoon‐Hee , Cho Jae‐Hyoung , Yoon Kun‐Ho
Published: December 2012

The ‘diabetes epidemic’ is an important health and socioeconomic problem worldwide. Type 2 diabetes is a chronic disease with gradual deterioration in glucose metabolism which causes multiple systemic complications. Therefore, early intervention in the prediabetic stage is a valuable approach to reduce diabetes development and related complications. Many clinical trials have suggested that lifestyle intervention, including moderate‐intensity exercise and diet control, and pharmacologic intervention using metformin, α‐glucosidase inhibitors, thiazolidinediones, anti‐obesity drugs and incretin mimics, are effective in preventing diabetes development. However, an individualized approach with careful consideration of the patient’s risk status and health economics is needed to perform a successful intervention programmes. In this review, we will summarize the known evidence on treatment‐ and cost‐effectiveness of drug and lifestyle treatment. Additionally, we will propose a strategic approach algorithm that is applicable to clinical practice.
Diabetes therapy‐focus on Asia: second‐line therapy debate: insulin/secretagogues
Authors: Eldor Roy , Raz Itamar
Published: December 2012

The following review is based on the second part of a debate entitled ‘Diabetes therapy‐ focus on Asia: 2nd line therapy: GLP1/DPP4 inhibitors versus Secretagogue/insulin therapy’, which was held during the ‘1st Asia Pacific Congress on Controversies to Consensus in Diabetes, Obesity and Hypertension (CODHy)’, in Shanghai, China, 2011. As such we reviewed only insulin and secretagogue therapy despite the existence of other therapeutic options. The article aims to shed light on the circumstances most adequate for use of these as second‐line agents, despite possible drawbacks. It is important to emphasize that regardless of it being a review of published evidence, it primarily represents the professional opinion of the writers.
Comparing the effectiveness of chronic water column tests with the crustaceans Hyalella azteca (order: Amphipoda) and Ceriodaphnia dubia (order: Cladocera) in detecting toxicity of current-use insecticides
Authors: Deanovic Linda A. , Markiewicz Dan , Stillway Marie , Fong Stephanie , Werner Inge
Published: December 2012

Standard U.S. Environmental Protection Agency laboratory tests are used to monitor water column toxicity in U.S. surface waters. The water flea Ceriodaphnia dubia is among the most sensitive test species for detecting insecticide toxicity in freshwater environments.Its usefulness is limited, however, when water conductivity exceeds 2,000 µS/cm (approximately 1 ppt salinity) and test effectiveness is insufficient. Water column toxicity tests using the euryhaline amphipod Hyalella azteca could complement C. dubia tests; however, standard chronic protocols do not exist. The present study compares the effectiveness of two water column toxicity tests in detecting the toxicity of two organophosphate (OP) and two pyrethroid insecticides: the short-term chronic C. dubia test, which measures mortality and fecundity, and a 10-d H. azteca test, which measures mortality and growth. Sensitivity was evaluated by comparing effect data, and end point variability was evaluated by comparing minimum significant differences. Tests were performed in synthetic water and filtered ambient water to quantify the influence of water matrix on effect concentrations. The H. azteca test detected pyrethroid toxicity far more effectively, while the C. dubia test was more sensitive to OPs. Among endpoints, H. azteca mortality was most robust. The results demonstrate that the H. azteca test is preferable when conductivity of water samples is 2,000 to 10,000 µS/cm or if contaminants of concern include pyrethroid insecticides. Environ. Toxicol. Chem. 2013;32:707–712. © 2012 SETAC
Mercury in the seafood and human exposure in coastal area of Guangdong province, South China
Authors: Li Ping , Feng Xinbin , Liang Peng , Man Chan Hing , Yan Haiyu , Chen Laiguo
Published: December 2012

Consumption of fish and aquatic products is considered to be the main pathway of human exposure to methylmercury (MeHg). To assess human health risk through seafood consumption in a coastal area of Guangdong Province, South China, a total of 518 seafood samples (including fish, shrimp, crabs, and mollusks) were collected from 11 coastal cities for total mercury (THg) analysis. The THg concentrations varied significantly among different seafood groups and ranged from 0.11 to 317 ng/g (with a mean of 37.2 ng/g). The THg concentrations were relatively low compared with fish from Europe and North America, and no samples exceeded the national limit recommended by the Standardization Administration of China (0.5 µg/g wet wt). The ecological functional groups and cultured styles have significant effects on THg concentrations in the fish tissue. The median of probable daily intakes (PDIs) of MeHg via seafood consumption ranged from 42.6 to 71.4 ng/kg/d for different age groups, with fish contributing the major portion (84%). The results indicated potential health risks associated with seafood consumption for the general population in the coastal area of Guangdong Province, South China. Environ. Toxicol. Chem. 2013;32:541–547. © 2012 SETAC
Targeting of DICE1 tumor suppressor by Epstein–Barr virus‐encoded miR‐BART3* microRNA in nasopharyngeal carcinoma
Authors: Lei Ting , Yuen Kit‐San , Xu Rui , Tsao Sai Wah , Chen Honglin , Li Mengfeng , Kok Kin‐Hang , Jin Dong‐Yan
Published: December 2012

Latent infection with Epstein–Barr virus (EBV) is associated with several types of malignancies including nasopharyngeal carcinoma (NPC), which is particularly more prevalent in Southern China. EBV expresses at least 44 mature microRNAs (miRNAs) to modulate the activity of viral and cellular RNAs, but the targets of these EBV‐encoded miRNAs in NPC are not well understood. In this report, we characterized DICE1 tumor suppressor to be a cellular target of EBV miR‐BART3* miRNA. miR‐BART3* was abundantly expressed in NPC cells. The target site of miR‐BART3* located in the 3′‐untranslated region of DICE1 transcript was identified and characterized. Enforced expression of miR‐BART3* or its precursor pre‐miR‐BART3 led to down‐regulation of endogenous DICE1 expression. Inhibition of endogenous miR‐BART3* in NPC cells with anti‐miR‐BART3* oligonucleotide inhibitor resulted in increased expression of DICE1 protein. On the contrary, expression of miR‐BART3* overcame the growth suppressive activity of DICE1 and stimulated cell proliferation. Consistent with its tumor suppressive function, DICE1 was underexpressed in EBV‐expressing NPC tumor tissues. Taken together, our findings suggest that EBV encoded miR‐BART3* miRNA targets DICE1 tumor suppressor to promote cellular growth and transformation in NPC.
Reciprocal longitudinal associations between pain and depressive symptoms in adolescents
Authors: Lewandowski Holley A. , Law E.F. , Zhou C. , Murphy L. , Clarke G. , Palermo T.M.
Published: December 2012

Background

Elevated depressive symptoms are common in youth with chronic pain, and pain symptoms are frequent in adolescents with depressive disorders. While studies have identified concurrent associations between pain and depression over time in youth, it is unclear how change in one symptom impacts change in the other symptom.

Methods

This three‐time point 12‐month longitudinal study examined reciprocal associations among pain and depression in a clinical sample of adolescents (12–18) diagnosed with chronic pain (n = 55) or a depressive disorder (n = 40). Mixed‐effects multivariate models were used to test if changes over a preceding time interval predicted symptom severity at subsequent time points. Study group, age, sex, race, baseline pain intensity and baseline depressive symptoms were included as covariates.

Results

Generalized estimating equations revealed that pain and depressive symptoms were significantly associated over time (β = 1.54; p < 0.001). As hypothesized, changes in pain were associated with subsequent depressive symptoms (β = 1.16; p < 0.001). Conversely, changes in depressive symptoms predicted subsequent pain (β = 0.026; p < 0.05), but with a weaker association. In the model predicting pain, an interaction between depressive symptoms and study group emerged (β = −0.02; p < 0.05), with change in depressive symptoms having the greatest impact on pain in the depressed sample.

Conclusions

Findings extend previous adult research to an adolescent sample showing changes in pain intensity are predictive of subsequent depressive symptoms. In comparison to adult data, changes in depressive symptoms had less impact on subsequent pain in youth. Future research can examine how targeting persistent pain may also aid the treatment of depressive symptoms in adolescents.
Low‐level laser therapy (LLLT) reduces oxidative stress in primary cortical neurons in vitro
Authors: Huang Ying‐Ying , Nagata Kazuya , Tedford Clark E. , McCarthy Thomas , Hamblin Michael R.
Published: December 2012

Low‐level laser (light) therapy (LLLT) involves absorption of photons being in the mitochondria of cells leading to improvement in electron transport, increased mitochondrial membrane potential (MMP), and greater ATP production. Low levels of reactive oxygen species (ROS) are produced by LLLT in normal cells that are beneficial. We exposed primary cultured murine cortical neurons to oxidative stressors: hydrogen peroxide, cobalt chloride and rotenone in the presence or absence of LLLT (3 J/cm2, CW, 810 nm wavelength laser, 20 mW/cm2). Cell viability was determined by PrestoblueTM assay. ROS in mitochondria was detected using Mito‐sox, while ROS in cytoplasm was detected with CellRoxTM. MMP was measured with tetramethylrhodamine. In normal neurons LLLT elevated MMP and increased ROS. In oxidatively‐stressed cells LLLT increased MMP but reduced high ROS levels and protected cultured cortical neurons from death. Although LLLT increases ROS in normal neurons, it reduces ROS in oxidatively‐stressed neurons. In both cases MMP is increased. These data may explain how LLLT can reduce clinical oxidative stress in various lesions while increasing ROS in cells in vitro. (© 2013 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Long‐distance laser propulsion and deformation‐ monitoring of cells in optofluidic photonic crystal fiber
Authors: Unterkofler Sarah , Garbos Martin K. , Euser Tijmen G. , Russell Philip St. J.
Published: December 2012

We introduce a unique method for laser‐propelling individual cells over distances of 10s of cm through stationary liquid in a microfluidic channel. This is achieved by using liquid‐filled hollow‐core photonic crystal fiber (HC‐PCF). HC‐PCF provides low‐loss light guidance in a well‐defined single mode, resulting in highly uniform optical trapping and propulsive forces in the core which at the same time acts as a microfluidic channel. Cells are trapped laterally at the center of the core, typically several microns away from the glass interface, which eliminates adherence effects and external perturbations. During propagation, the velocity of the cells is conveniently monitored using a non‐imaging Doppler velocimetry technique. Dynamic changes in velocity at constant optical powers up to 350 mW indicate stress‐induced changes in the shape of the cells, which is confirmed by bright‐field microscopy. Our results suggest that HC‐PCF will be useful as a new tool for the study of single‐cell biomechanics. (© 2013 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Stimuli responsive deswelling of radiation synthesized collagen hydrogel in simulated physiological environment
Authors: Zhang Xiangmei , Xu Ling , Wei Shicheng , Zhai Maolin , Li Jiuqiang
Published: December 2012

Collagen hydrogels were prepared via radiation crosslinking. The simulated physiological environmental effects related to their biomedical applications on the volume phase transition of collagen hydrogel were studied, that is stimuli response to ions, temperature, and pH. The deswelling behavior of collagen hydrogel depends on the salt concentration, temperature, pH, and the hydrogel preparation procedure. Meanwhile, hydrogel structure related to the volume phase transition was investigated by FTIR, fluorescence spectrum, and HR‐MAS NMR. Deswelling in salt solution caused little change on collagen conformation, and a denser network led to more significant tyrosine‐derived fluorescence quenching. Hydrogen bonding between hydrated water and collagen polypeptide chain was dissociated and the activity of hydrophobic side chain increased, inducing a higher extent of contraction with the increasing of salt concentration. Moreover, salt solution treatments weakened the electrostatic interactions, side chains interactions, and hydrogen bonding of collagen hydrogel, which reduced the thermal stability of collagen hydrogel. Comparing with cell‐free collagen hydrogel contraction, fibroblasts did not aggravate contraction of collagen hydrogel significantly. This study elucidated the deswelling mechanism of radiation crosslinked collagen hydrogel in simulated physiological environment and provides strategies for controlling the stimuli response of collagen hydrogel in biomedical application. © 2012 Wiley Periodicals, Inc. J Biomed Mater Res Part A, 2013.
pH‐responsive hydrogels with dispersed hydrophobic nanoparticles for the oral delivery of chemotherapeutics
Authors: Schoener Cody A. , Hutson Heather N. , Peppas Nicholas A.
Published: December 2012

Amphiphilic polymer carriers were formed by polymerizing a hydrophilic, pH‐responsive hydrogel composed of poly(methacrylic–grafted–ethylene glycol) (P(MAA‐g‐EG)) in the presence of hydrophobic PMMA nanoparticles. These polymer carriers were varied in PMMA nanoparticle content to elicit a variety of physiochemical properties which would preferentially load doxorubicin, a hydrophobic chemotherapeutic, and release doxorubicin locally in the colon for the treatment of colon cancers. Loading levels ranged from 49% to 64% and increased with increasing nanoparticle content. Doxorubicin loaded polymers were released in a physiological model where low pH was used to simulate the stomach and then stepped to more neutral conditions to simulate the upper small intestine. P(MAA‐g‐EG) containing nanoparticles were less mucoadhesive as determined using a tensile tester, polymer samples, and fresh porcine small intestine. The cytocompatibility of the polymer materials were assessed using cell lines representing the GI tract and colon cancer and were noncytotoxic at varying concentrations and exposure times. © 2012 Wiley Periodicals, Inc. J Biomed Mater Res Part A, 2013.
Acceleration of coarse grain molecular dynamics on GPU architectures
Authors: Shkurti Ardita , Orsi Mario , Macii Enrico , Ficarra Elisa , Acquaviva Andrea
Published: December 2012

Coarse grain (CG) molecular models have been proposed to simulate complex systems with lower computational overheads and longer timescales with respect to atomistic level models. However, their acceleration on parallel architectures such as graphic processing units (GPUs) presents original challenges that must be carefully evaluated. The objective of this work is to characterize the impact of CG model features on parallel simulation performance. To achieve this, we implemented a GPU‐accelerated version of a CG molecular dynamics simulator, to which we applied specific optimizations for CG models, such as dedicated data structures to handle different bead type interactions, obtaining a maximum speed‐up of
$14$
on the NVIDIA GTX480 GPU with Fermi architecture. We provide a complete characterization and evaluation of algorithmic and simulated system features of CG models impacting the achievable speed‐up and accuracy of results, using three different GPU architectures as case studies. © 2012 Wiley Periodicals, Inc.
Calculation of wave‐functions with frozen orbitals in mixed quantum mechanics/molecular mechanics methods. Part I. Application of the Huzinaga equation
Authors: Ferenczy György G.
Published: December 2012

Mixed quantum mechanics/quantum mechanics (QM/QM) and quantum mechanics/molecular mechanics (QM/MM) methods make computations feasible for extended chemical systems by separating them into subsystems that are treated at different level of sophistication. In many applications, the subsystems are covalently bound and the use of frozen localized orbitals at the boundary is a possible way to separate the subsystems and to ensure a sensible description of the electronic structure near to the boundary. A complication in these methods is that orthogonality between optimized and frozen orbitals has to be warranted and this is usually achieved by an explicit orthogonalization of the basis set to the frozen orbitals. An alternative to this approach is proposed by calculating the wave‐function from the Huzinaga equation that guaranties orthogonality to the frozen orbitals without basis set orthogonalization. The theoretical background and the practical aspects of the application of the Huzinaga equation in mixed methods are discussed. Forces have been derived to perform geometry optimization with wave‐functions from the Huzinaga equation. Various properties have been calculated by applying the Huzinaga equation for the central QM subsystem, representing the environment by point charges and using frozen strictly localized orbitals to connect the subsystems. It is shown that a two to three bond separation of the chemical or physical event from the frozen bonds allows a very good reproduction (typically around 1 kcal/mol) of standard Hartree–Fock–Roothaan results. The proposed scheme provides an appropriate framework for mixed QM/QM and QM/MM methods. © 2012 Wiley Periodicals, Inc.
Solvent‐free Synthesis of Novel and Known Octahydroquinazolinones/thiones by the Use of ZrOCl2.8H2O as a Highly Efficient and Reusable Catalyst
Authors: Karami Sajad , Karami Bahador , Khodabakhshi Saeed
Published: December 2012

A solvent‐free reaction between urea/thiourea, dimedone and aromatic aldehydes in the presence of catalytic amounts of zirconium (IV) oxychloride octahydrate (ZrOCl2.8H2O) as a powerfull Lewis acid leads to octahydroquinazolinone/thione derivatives in good yields. This method has advantages such as avoidance of the organic solvents, production of pure products without any by‐product, short reaction times and simple operation.
The somatotopic organization of the olfactory bulb in elasmobranchs
Authors: Meredith Tricia L. , Kajiura Stephen M. , Hansen Anne
Published: December 2012

The olfactory bulbs (OBs) are bilaterally paired structures in the vertebrate forebrain that receive and process odor information from the olfactory receptor neurons (ORNs) in the periphery. Virtually all vertebrate OBs are arranged chemotopically, with different regions of the OB processing different types of odorants. However, there is some evidence that elasmobranch fishes (sharks, rays, and skates) may possess a gross somatotopic organization instead. To test this hypothesis, we used histological staining and retrograde tracing techniques to examine the morphology and organization of ORN projections from the olfactory epithelium (OE) to the OB in three elasmobranch species with varying OB morphologies. In all three species, glomeruli in the OB received projections from ORNs located on only the three to five lamellae situated immediately anterior within the OE. These results support that the gross arrangement of the elasmobranch OB is somatotopic, an organization unique among fishes and most other vertebrates. In addition, certain elasmobranch species possess a unique OB morphology in which each OB is physically subdivided into two or more “hemi‐olfactory bulbs.” Somatotopy could provide a preadaptation which facilitated the evolution of olfactory hemibulbs in these species. J. Morphol., 2013. © 2012 Wiley Periodicals, Inc.
Unique features of pedicellate attachment of the upper jaw teeth in the adult gobiid fish Sicyopterus japonicus (Teleostei, Gobiidiae): Morphological and structural characteristics and development
Authors: Sahara Noriyuki , Moriyama Keita , Iida Midori , Watanabe Shun
Published: December 2012

Sicyopterus japonicus (Teleostei, Gobiidae), a hill‐stream herbivorous gobiid fish, possesses an unusual oral dentition among teleost fishes on account of its feeding habitat. By using scanning electron microscopy, light microscopy, and transmission electron microscopy, including vital staining with tetracycline, we examined the development of the attachment tissues of the upper jaw teeth in this fish. The functional teeth of S. japonicus had an asymmetrical dentine shaft. The dentine shaft attached to the underlying uniquely shaped pedicel by means of two different attachment mechanisms. At the lingual base, collagen fiber bundles connected the dentine shaft with the pedicel (hinged attachment), whereas the labial base articulated with an oval‐shaped projection of the pedicel (articulate attachment). The pedicel bases were firmly ankylosed to the crest of the thin flange of porous spongy bone on the premaxillary bone, which afforded a flange‐groove system on the labial surface of the premaxillary bone. Developmentally, the pedicel and thin flange of spongy bone were completely different mineralized attachment tissues. The pedicel had a dual origin, i.e., the dental papilla cells, which differentiated into odontoblasts that constructed the internal surface of the pedicel, and the mesenchymal cells, which differentiated into osteoblasts that formed the outer face of the pedicel. A thin flange of spongy bone was deposited on the superficial resorbed labial side of the premaxillary bone proper, and later rapid bone remodeling proceeded toward the pedicel base. These unique features of pedicellate tooth attachment for the upper jaw teeth in the adult S. japonicus are highly modified teeth for enhancing the ability of individual functional teeth to move closely over irregularities in the rock surfaces during the scraping of algae. J. Morphol., 2013. © 2012 Wiley Periodicals, Inc.
Reconstruction of cranial and hyobranchial muscles in the triassic temnospondylGerrothoraxprovides evidence for akinetic suction feeding
Authors: Witzmann Florian , Schoch Rainer R.
Published: December 2012

The cranial and hyobranchial muscles of the Triassic temnospondylGerrothoraxhave been reconstructed based on direct evidence (spatial limitations, ossified muscle insertion sites on skull, mandible, and hyobranchium) and on phylogenetic reasoning (with extant basal actinopterygians and caudates as bracketing taxa). The skeletal and soft‐anatomical data allow the reconstruction of the feeding strike of this bottom‐dwelling, aquatic temnospondyl. The orientation of the muscle scars on the postglenoid area of the mandible indicates that the depressor mandibulae was indeed used for lowering the mandible and not to raise the skull as supposed previously and implies that the skull including the mandible must have been lifted off the ground during prey capture. It can thus be assumed thatGerrothoraxraised the head toward the prey with the jaws still closed. Analogous to the bracketing taxa, subsequent mouth opening was caused by action of the strong epaxial muscles (further elevation of the head) and the depressor mandibulae and rectus cervicis (lowering of the mandible). During mouth opening, the action of the rectus cervicis muscle also rotated the hyobranchial apparatus ventrally and caudally, thus expanding the buccal cavity and causing the inflow of water with the prey through the mouth opening. The strongly developed depressor mandibulae and rectus cervicis, and the well ossified, large quadrate‐articular joint suggest that this action occurred rapidly and that powerful suction was generated. Also, the jaw adductors were well developed and enabled a rapid mouth closure. In contrast to extant caudate larvae and most extant actinopterygians (teleosts), no cranial kinesis was possible in theGerrothoraxskull, and therefore suction feeding was not as elaborate as in these extant forms. This reconstruction may guide future studies of feeding in extinct aquatic tetrapods with ossified hyobranchial apparatus. J. Morphol., 2013. © 2012 Wiley Periodicals, Inc.
Rainfall variations in south‐eastern Australia part 2: a comparison of documentary, early instrumental and palaeoclimate records, 1788–2008
Authors: Gergis Joëlle , Ashcroft Linden
Published: December 2012

In part 1 of this study, Fenby and Gergis (Fenby C, Gergis J. 2012. A rainfall history of south‐eastern Australia Part 1: comparing evidence from documentary and palaeoclimate records, 1788–1860. International Journal of Climatology) established a documentary chronology of droughts and wet years in south‐eastern Australia (SEA) from first European settlement in 1788 until widespread meteorological observations begin in 1860. We now compare this newly developed documentary record to a five‐station network of historical instrumental rainfall observations from the Sydney region for 1832–1859, and a 45‐station rainfall network from a broader range of SEA locations over the 1860–2008 period. After assessing geographical biases in the documentary and instrumental record due to population settlement, we identify eastern New South Wales (NSW) as the subregion of SEA that is capable of providing a continuous record of wet and dry years back to 1788. Documentary, historical instrumental and modern rainfall observations are then combined to develop an eastern NSW drought and wet year index over the 1788–2008 period. The eastern NSW drought and wet year index is compared to palaeoclimate reconstructions of SEA rainfall and El Niño–Southern Oscillation (ENSO) since 1788. We investigate the relationship between droughts and wet years in eastern NSW and ENSO back to 1788, noting that the coastal NSW rainfall–ENSO relationship is not as pronounced as in inland areas of eastern Australia. While it is clear that ENSO influences rainfall variability in the broader SEA region, the signal recorded in coastal NSW is weak. This is most likely reflecting local orographic rainfall effects and deficiencies in the wet phase of the documentary record. Nonetheless, this study is the first of its kind in the Australasian region to combine documentary, early instrumental and modern meteorological rainfall observations using internationally comparable techniques, a significant advance in historical climatology for the region. The results of this study provide an opportunity for Australia to be included in cross‐regional drought comparisons from the Indo–Pacific regions of the Southern Hemisphere.
Canadian RCM projected changes to high flows for Québec watersheds using regional frequency analysis
Authors: Clavet‐Gaumont J. , Sushama L. , Khaliq M. N. , Huziy O. , Roy R.
Published: December 2012

Information related to changes in streamflow characteristics is important in the management and future planning of various water resources‐related projects in the context of a changing climate. In this study, projected changes to selected return levels of high flows for 21 watersheds, located mainly in the Québec province of Canada, are assessed following regional frequency analysis (RFA). This assessment is based on a ten‐member ensemble of Canadian regional climate model (CRCM) transient climate change simulations, of which five correspond to current 1970–1999 period and the remaining five are the matching simulations for the future 2041–2070 period. This is the first comprehensive study on high‐flow characteristics for the entire 21 watersheds in the context of a changing climate using the RFA approach, which allows better estimation of return levels, particularly for higher return periods, than single site/grid‐cell based analysis. Validation of the European Centre for Medium‐Range Weather Forecasts Re‐Analysis‐driven CRCM simulated 5‐, 10‐, 30‐ and 50‐year return levels against those observed at selected gauging stations suggests a general overestimation, with average differences of 9 and 12% (3–5%) for the 5‐ and 10‐year (30‐ and 50‐year) return levels, respectively. Results of ensemble averaged projected changes to regional return levels show increases for most of the watersheds. In particular, changes to 5‐ and 10‐year (compared to 30‐ and 50‐year) regional return levels are found to be statistically significant more often for northern watersheds compared to the rest. An evaluation of confidence in projected changes to selected regional return levels, based on five current/future period simulation pairs, reveal a higher level of confidence for northern watersheds. When regional level projected changes are developed at the CRCM grid‐cell level, a pattern similar to that for regional level changes is noticed, though with slightly increased range of changes.
Matrix metalloproteinase‐12 is associated with overall survival in Chinese patients with gastric cancer
Authors: Zheng Jianyong , Chu Dake , Wang Desheng , Zhu Yongsheng , Zhang Xiaoyin , Ji Gang , Zhao Haihong , Wu Guosheng , Du Jianjun , Zhao Qingchuan
Published: December 2012

Background and Objectives

Matrix metalloproteinase‐12 (MMP‐12) plays an important role in invasion and metastasis of human solid tumor cells. This study aimed to investigate the association of MMP‐12 with overall survival in human gastric cancer.

Methods

Gastric cancer and adjacent normal tissue specimens were collected from 165 patients who had not received neoadjuvant chemotherapy. MMP‐12 expression was determined by immunohistochemical staining, and the results were analyzed statistically in relation to the overall survival of the patients.

Results

MMP‐12 expression was increased in gastric cancer compared with that observed in normal tissues. Increased MMP‐12 expression was associated with tumor invasion, lymph node metastasis, distant metastasis, and TNM stage. No correlations were detected between MMP‐12 expression and age, sex, differentiation status, tumor site, or Lauren classification. Moreover, patients with MMP‐12 positive gastric cancer tended to have worse overall survival compared with those patients without MMP‐12 expression.

Conclusions

The study results showed that increased expression of MMP‐12 was associated with tumor progression in gastric cancer. It also provided the first evidence for MMP‐12 expression in gastric cancer as an independent prognostic factor. J. Surg. Oncol. 2013;107:746–751. © 2012 Wiley Periodicals, Inc.
Investigation of the Polymerization Behavior and Regioselectivity of Fluorene Diamine‐Based Benzoxazines
Authors: Wang Jun , He Xuan‐Yu , Liu Jun‐Ting , Liu Wen‐Bin , Yang Lei
Published: December 2012

A series of fluorene diamine‐based benzoxazine monomers are prepared from the reaction of 9,9‐bis‐(4‐aminophenyl)‐fluorene with paraformaldehyde and unsubstituted or substituted phenols. Unsubstituted and substituted phenol‐based benzoxazines show different polymerization behaviors and give polymers with different thermal properties. The ortho and para positions on the phenol for benzoxazines based on phenol and m‐cresol could concurrently participate in the crosslinking reaction during thermal ring‐opening polymerization to form Mannich and methylene bridges at high temperature. The glass‐transition temperature and thermal stability of the resulting polymers are much higher than those of other substituted phenol‐based polybenzoxazines and bisphenol fluorene‐based polybenzoxazines.
Cross‐talk between microRNAs, nuclear factor E2‐related factor 2, and heme oxygenase‐1 in ochratoxin A‐induced toxic effects in renal proximal tubular epithelial cells
Authors: Stachurska Anna , Ciesla Maciej , Kozakowska Magdalena , Wolffram Siegfried , Boesch‐Saadatmandi Christine , Rimbach Gerald , Jozkowicz Alicja , Dulak Jozef , Loboda Agnieszka
Published: December 2012

Scope

Ochratoxin A (OTA) is a mycotoxin exhibiting nephrotoxic and potential carcinogenic activity. We investigated the cross‐talk between microRNAs, nuclear factor E2‐related factor 2 (Nrf2), and heme oxygenase‐1 (HO‐1) in ochratoxin A‐mediated effects.

Methods and results

In porcine renal proximal tubular cells, OTA increased expression of profibrotic transforming growth factors β (TGFβ) while concomitantly decreasing expression of Nrf2, HO‐1, and erythropoietin. Adenoviral overexpression of Nrf2 counteracted OTA‐mediated reduction in HO‐1 and erythropoietin expression and cell proliferation as well as increase in reactive oxygen species (ROS) generation and TGFβ expression. Additionally, inhibition of HO activity enhanced whereas adenoviral overexpression of HO‐1 reduced expression of TGFβ. Moreover, antioxidants, N‐acetyl‐cysteine and desferioxamine, prevented OTA‐mediated enhancement of ROS generation, and TGFβ expression. Finally, OTA modulated microRNA processing by upregulating LINeage protein 28 and DiGeorge syndrome critical region‐8, increasing the total pool of cellular microRNAs and elevating the expression of miR‐132 and miR‐200c. Inhibition of miR‐132 by specific antagomir restored the OTA‐driven reduction in Nrf2 expression. Moreover, anti‐miR‐132 and anti‐miR‐200c counteracted OTA‐mediated decrease in HO‐1 levels as well as increase in ROS production and TGFβ expression.

Conclusion

We showed that attenuation of Nrf2 and HO‐1 expression through induction of miR‐132 and miR‐200c by OTA elevates ROS levels and profibrotic TGFβ expression.
Expression and localization of creatine kinase in the preimplantation embryo
Authors: Forsey Katherine E. , Ellis Peter J. , Sargent Carole A. , Sturmey Roger G. , Leese Henry J.
Published: December 2012

Creatine Kinase (CK) catalyses the “creatine shuttle,” the reversible conversion of creatine phosphate to creatine with the liberation of ATP. This article examines the potential role of the creatine shuttle in the provision of ATP during mouse preimplantation embryo development. Using quantitative PCR, transcripts of four subunit isoforms of CK—CKM, CKB, CKMT1, and CKMT2—were detectable at all developmental stages, from the presumptive zygote to late blastocyst, but there was no obvious pattern in gene expression. By contrast, total CK biochemical activity, measured by a novel method, was relatively constant from the 2‐ to 8‐cell stage, before exhibiting a significant decrease in activity at the blastocyst stage. Immunocytochemical studies revealed a marked association of CKB with the mitotic spindle in 2‐ and 4‐cell mouse embryos, consistent with the proposition that the creatine shuttle plays a key role in local delivery of ATP during cytokinesis. Endogenous creatine was detected in the blastocyst at a level of 0.53 pmol/embryo. In conclusion, we believe that creatine phosphate can now be added to the list of potential sources of ATP during preimplantation development. Mol. Reprod. Dev. 80: 185–192, 2013. © 2013 Wiley Periodicals, Inc.
Monitoring bovine fetal fibroblast reprogramming utilizing a bovine NANOG promoter‐driven EGFP reporter system
Authors: Lei Lei , Li Lei , Du Fuliang , Chen Chien‐Hong , Wang Huayan , Keefer Carol L.
Published: December 2012

NANOG is an essential transcription factor involved in the proliferation and maintenance of embryonic stem cells (ESC) and reprogramming of somatic cells to a pluripotent state. Oct4 and Nanog promoter‐driven enhanced green fluorescent protein (EGFP) reporters have been employed for establishing lines of induced pluripotent stem cells (iPSC) from mouse, human, and pig. In ruminants, including cattle, in which no fully validated ESC lines have been established, iPSC generated by reprogramming somatic cells to an ESC‐like state may prove useful in the production of genetically modified livestock. In this study, utility of the bovine NANOG reporter was tested for use with cattle. Seven proximal bovine NANOG promoter fragments of different size were fused to the LUC gene, and were tested in mouse ESC lines using a dual‐luciferase assay. Three of the bovine NANOG promoters, 315 bp (−134/+181), 446 bp (−265/+181), and 1,100 bp (−919/+181), were fused to a nuclear localized signal EGFP reporter gene. The fidelity of these constructs was analyzed by transfection into mouse ESC and bovine fetal fibroblasts (bFFs), and subsequent reprogramming of the bFF. Fusion of the transgenic bFF with human teratocarcinoma (NTERA2) cells induced nuclear expression of the EGFP reporter. Similarly, bFF‐derived somatic cell nuclear transfer (SCNT) embryos expressed EGFP in a stage‐ and location‐appropriate manner. Following reprogramming of transgenic bFFs for 10 days with an Oct4‐Sox2‐Klf4‐cMyc vector, iPSC expressed EGFP and alkaline phosphatase. These results indicate that NANOG reporters can be used to monitor nuclear reprogramming of bFFs and to distinguish cell allocation in SCNT‐derived embryos. Mol. Reprod. Dev. 80: 193–203, 2013. © 2013 Wiley Periodicals, Inc.
Error model for reduction of cardiac and respiratory motion effects in quantitative liver DW‐MRI
Authors: Murphy Paul , Wolfson Tanya , Gamst Anthony , Sirlin Claude , Bydder Mark
Published: December 2012

Diffusion‐weighted images of the liver exhibit signal dropout from cardiac and respiratory motion, particularly in the left lobe. These artifacts cause bias and variance in derived parameters that quantify intravoxel incoherent motion. Many models of diffusion have been proposed, but few separate attenuation from diffusion or perfusion from that of bulk motion. The error model proposed here (Beta*LogNormal) is intended to accomplish that separation by modeling stochastic attenuation from bulk motion as multiplication by a Beta‐distributed random variate. Maximum likelihood estimation with this error model can be used to derive intravoxel incoherent motion parameters separate from signal dropout, and does not require a priori specification of parameters to do so. Liver intravoxel incoherent motion parameters were derived for six healthy subjects under this error model and compared with least‐squares estimates. Least‐squares estimates exhibited bias due to cardiac and respiratory gating and due to location within the liver. Bias from these factors was significantly reduced under the Beta*LogNormal model, as was within‐organ parameter variance. Similar effects were appreciable in diffusivity maps in two patients with focal liver lesions. These results suggest that, relative to least‐squares estimation, the Beta*LogNormal model accomplishes the intended reduction of bias and variance from bulk motion in liver diffusion imaging. Magn Reson Med 70:1460–1469, 2013. © 2012 Wiley Periodicals, Inc.
Exchange‐dependent relaxation in the rotating frame for slow and intermediate exchange – modeling off‐resonant spin‐lock and chemical exchange saturation transfer
Authors: Zaiss Moritz , Bachert Peter
Published: December 2012

Chemical exchange observed by NMR saturation transfer (CEST) and spin‐lock (SL) experiments provide an MRI contrast by indirect detection of exchanging protons. The determination of the relative concentrations and exchange rates is commonly achieved by numerical integration of the Bloch–McConnell equations. We derive an analytical solution of the Bloch–McConnell equations that describes the magnetization of coupled spin populations under radiofrequency irradiation. As CEST and off‐resonant SL are equivalent, their steady‐state magnetization and dynamics can be predicted by the same single eigenvalue: the longitudinal relaxation rate in the rotating frame R1ρ. For the case of slowly exchanging systems, e.g. amide protons, the saturation of the small proton pool is affected by transverse relaxation (R2b). It turns out, that R2b is also significant for intermediate exchange, such as amine‐ or hydroxyl‐exchange or paramagnetic CEST agents, if pools are only partially saturated. We propose a solution for R1ρ that includes R2 of the exchanging pool by extending existing approaches, and verify it by numerical simulations. With the appropriate projection factors, we obtain an analytical solution for CEST and SL for nonzero R2 of the exchanging pool, exchange rates in the range 1–104 Hz, B1 from 0.1 to 20 μT and arbitrary chemical shift differences between the exchanging pools, whilst considering the dilution by direct water saturation across the entire Z‐spectra. This allows the optimization of irradiation parameters and the quantification of pH‐dependent exchange rates and metabolite concentrations. In addition, we propose evaluation methods that correct for concomitant direct saturation effects. It is shown that existing theoretical treatments for CEST are special cases of this approach. Copyright © 2012 John Wiley & Sons, Ltd.
Topology optimization of structures using meshless density variable approximants
Authors: Luo Zhen , Zhang Nong , Wang Yu , Gao Wei
Published: December 2012

This paper proposes a new structural topology optimization method using a dual‐level point‐wise density approximant and the meshless Galerkin weak‐forms, totally based on a set of arbitrarily scattered field nodes to discretize the design domain. The moving least squares (MLS) method is used to construct shape functions with compactly supported weight functions, to achieve meshless approximations of system state equations. The MLS shape function with the zero‐order consistency will degenerate to the well‐known ‘Shepard function’, while the MLS shape function with the first‐order consistency refers to the widely studied ‘MLS shape function’. The Shepard function is then applied to construct a physically meaningful dual‐level density approximant, because of its non‐negative and range‐restricted properties. First, in terms of the original set of nodal density variables, this study develops a nonlocal nodal density approximant with enhanced smoothness by incorporating the Shepard function into the problem formulation. The density at any node can be evaluated according to the density variables located inside the influence domain of the current node. Second, in the numerical implementation, we present a point‐wise density interpolant via the Shepard function method. The density of any computational point is determined by the surrounding nodal densities within the influence domain of the concerned point. According to a set of generic design variables scattered at field nodes, an alternative solid isotropic material with penalization model is thus established through the proposed dual‐level density approximant. The Lagrangian multiplier method is included to enforce the essential boundary conditions because of the lack of the Kronecker delta function property of MLS meshless shape functions. Two benchmark numerical examples are employed to demonstrate the effectiveness of the proposed method, in particular its applicability in eliminating numerical instabilities. Copyright © 2012 John Wiley & Sons, Ltd.
Howard's algorithm in a phase‐field topology optimization approach
Authors: Wallin Mathias , Ristinmaa Matti
Published: December 2012

The topology optimization problem is formulated in a phase‐field approach. The solution procedure is based on the Allan–Cahn diffusion model where the conservation of volume is enforced by a global constraint. The functional defining the minimization problem is selected such that no penalization is imposed for full and void materials. Upper and lower bounds of the density function are enforced by infinite penalty at the bounds. A gradient term that introduces cost for boundaries and thereby regularizing the problem is also included in the objective functional. Conditions for stationarity of the functional are derived, and it is shown that the problem can be stated as a variational inequality or a max–min problem, both defining a double obstacle problem. The numerical examples used to demonstrate the method are solved using the FEM, whereas the double obstacle problem is solved using Howard's algorithm. Copyright © 2012 John Wiley & Sons, Ltd.
A two‐level method in space and time for the Navier‐Stokes equations
Authors: Liu Qingfang , Hou Yanren , Liu Qingchang
Published: December 2012

A two‐level method in space and time for the time‐dependent Navier‐Stokes equations is considered in this article. The approximate solution uM∈HM is decomposed into the large eddy component v∈Hm(m < M) and the small eddy component w∈H. We obtain the large eddy component v by solving a standard Galerkin equation in a coarse‐level subspace Hm with a time step length k, whereas the small eddy component w is derived by solving a linear equation in an orthogonal complement subspace H with a time step length pk, where p is a positive integer. The analysis shows that our two‐level scheme has long‐time stability and can reach the same accuracy as the standard Galerkin method in fine‐level subspace HM for an appropriate configuration of p and m. Moreover, some numerical examples are provided to complement our theoretical analysis. © 2012 Wiley Periodicals, Inc. Numer Methods Partial Differential Eq, 2013
Some error estimates of finite volume element method for parabolic optimal control problems
Authors: Luo Xianbing , Chen Yanping , Huang Yunqing , Hou Tianliang
Published: December 2012

In this paper, the finite volume element method (FVEM) is applied to solve the distributed optimal control problems governed by parabolic equation. We use the method of variational discretization concept to approximate the problems. We consider a semi‐discrete and a fully discrete piecewise linear FVEMs. For the semi‐discrete method, the optimal order error estimates in continuous L ∞ (J; L2) and L ∞ (J; H1)‐norm are obtained; the suboptimal error estimates in continuous L ∞ (J; L ∞ )‐norm are also obtained. For the fully discrete method, the optimal order error estimates in discrete L2(J; L2) and L ∞ (J; L2)‐norm are derived. Numerical experiments are presented to test these theoretical results. Copyright © 2012 John Wiley & Sons, Ltd.
Synthesis and properties of networking waterborne polyurethane/silica nanocomposites by addition of poly(ester amine) dendrimer
Authors: Han Wensong
Published: December 2012

The second‐generation poly(ester amine) dendrimer was prepared by Michael addition reaction and esterification reaction at first. Then, a series of novel waterborne polyurethane (WPU)‐based composites were prepared by the addition of poly(ester amine) dendrimer into the WPU. The structures and the morphology of the WPU composites were measured with Fourier transform infrared spectrometer, scanning electron microscopy, and X‐ray diffraction. SEM images revealed that the nanosilica was well dispersed in the WPU matrix. The mechanical properties of the WPU composites were improved with the addition of poly (ester amine) dendrimer. The dynamic mechanical thermal analysis results showed that the WPU composites had higher glass transition temperature than that of pure WPU, especially after incorporation of poly(ester amine) dendrimer. This conclusion is in good agreement with the differential scanning calorimetry results. The thermal properties of the pure WPU and its composites were investigated by thermogravimetric analysis. The results showed that the initial decompose temperature began from about 250°C, and had a little increase when introducing poly(ester amine) dendrimer into the WPU matrix. POLYM. COMPOS., 2012. © 2013 Society of Plastics Engineers