bluuebunny/crossref_metadata_2025 huggingface dataset:
Validation of WEPS for soil and PM10 loss from agricultural fields within the Columbia Plateau of the United States
Authors: Feng G. , Sharratt B.
Published: September 2006

Wind erosion from agricultural fields contributes to poor air quality within the Columbia Plateau of the United States. Erosion from fields managed in a conventional winter wheat–summer fallow rotation was monitored during the fallow period near Washtucna, WA, in 2003 and 2004. Loss of soil and PM10 (particulates ≤10 µm in diameter) was measured during six high wind events (sustained wind speed at 3 m height >6·4 m s−1). Soil loss associated with suspension, saltation and creep as well as PM10 emission was used to validate the Wind Erosion Prediction System (WEPS) erosion submodel. Input parameters for WEPS simulations were measured before each high wind event. The erosion submodel produced no erosion for half of the observed events and over‐predicted total soil loss by 200–700 kg ha−1 for the remaining events. The model appears to over‐predict total soil loss as a result of overestimating creep, saltation and suspension. The model both over‐predicted and under‐predicted PM10 loss. High values for the index of agreement (d > 0·5) suggest that the performance of the model is acceptable for the conditions of this study. While the performance of the model is acceptable, improvements can be made in modeling efficiency by better specifying the static threshold friction velocity or coefficients that govern emissions, abrasion and breakage of silt loams on the Columbia Plateau. Copyright © 2006 John Wiley & Sons, Ltd.
A Sinc‐collocation method with boundary treatment for the Stokes equations
Authors: Li Chen , Wu Xionghua
Published: September 2006

In Stokes equations the velocity u and the pressure p are coupled together by the imcompressibility condition div u=0 which makes the equations difficult to solve numerically. In this paper, a method named Sinc‐collocation method with boundary treatment (SCMBT) is applied to the Stokes equations. The numerical results show that our method is of high accuracy, of good convergence with little computational effort. Copyright © 2006 John Wiley & Sons, Ltd.
Error assessment of lattice Boltzmann equation method for variable viscosity flows
Authors: Chao Jianghui , Mei Renwei , Shyy Wei
Published: September 2006

In lattice Boltzmann simulations, variable viscosity can complicate the truncation error analysis and create additional interaction between the truncation error and the boundary condition error. In order to address this issue, two boundary conditions for the lattice Boltzmann equation (LBE) simulations are used, including an exact, but narrowly applicable scheme previously proposed by Noble et al. (Phys. Fluids 1995; 7(1):203–209) and the popular bounce‐back‐on‐link scheme. Using a 2‐D laminar channel flow with a specified variable viscosity as a test case, it is shown that the boundary treatment error does not have a significant interaction with the truncation error associated with variable viscosity. The truncation error behaviour of the LBE for flows with variable viscosity is further investigated through a comparison between the LBE solution and the Navier–Stokes solution, showing that in the presence of strong variable viscosity the truncation error behaviour of the LBE solution is consistent with that of the Navier–Stokes solution, indicating that the LBE model closely matches the Navier–Stokes model for fluid flows with large viscosity variation. Copyright © 2006 John Wiley & Sons, Ltd.
Modelling of wind wave‐induced bottom processes during the slack water periods in Tampa Bay, Florida
Authors: Shi John Z. , Luther Mark E. , Meyers Stephen
Published: September 2006

Estuarine process‐oriented modelling studies were undertaken to understand bottom boundary layer processes in Tampa Bay, Florida. A stationary shallow water wave model, SWAN, was applied to predict wind wave‐induced rms bottom orbital currents in Tampa Bay on a 70 × 100 curvilinear grid. Simulations were performed by using two idealized wind forcing (i.e. northeasterly winds of 10 and 20 m s−1) and high‐resolution bathymetry. Calculations of bed load and total load of fine sand were made by using the transport formulas of Van Rijn (J. Hydraulic Eng.1984;110:1431–1456) and Engelund–Hansen (A Monograph on Sediment Transport in Alluvial Streams. Copenhagen Technical Press: 1972), respectively. Simulations of wind wave induced currents reveal that they are important for fine sand transport along the shallow margins of the Tampa Bay. Modelled bottom orbital currents ranged from 0.05 to 0.39 m s−1. Total loads of fine sand ranged from 2.26×10−10to 1.05×10−5kg m−1s−1for northeasterly winds of 10 m s−1and from 2.46×10−5to 3.21×10−5kg m−1s−1for northeasterly winds of 20 m s−1. Wind wave‐induced bottom resuspension is an important process affecting water quality in Tampa Bay. Copyright © 2006 John Wiley & Sons, Ltd.
Statins induce differentiation and cell death in neurons and astroglia
Authors: März Pia , Otten Uwe , Miserez André R.
Published: September 2006

Statins are potent inhibitors of the hydroxy‐methyl‐glutaryl‐coenzyme A reductase, the rate limiting enzyme for cholesterol biosynthesis. Experimental and clinical studies with statins suggest that they have beneficial effects on neurodegenerative disorders. Thus, it was of interest to characterize the direct effects of statins on CNS neurons and glial cells. We have treated defined cultures of neurons and astrocytes of newborn rats with two lipophilic statins, atorvastatin and simvastatin, and analyzed their effects on morphology and survival. Treatment of astrocytes with statins induced a time‐ and dose‐dependent stellation, followed by apoptosis. Similarly, statins elicited programmed cell death of cerebellar granule neurons but with a higher sensitivity. Analysis of different signaling cascades revealed that statins fail to influence classical pathways such as Akt or MAP kinases, known to be activated in CNS cells. In addition, astrocyte stellation triggered by statins resembled dibutryl‐cyclic AMP (db‐cAMP) induced morphological differentiation. However, in contrast to db‐cAMP, statins induced upregulation of low‐density lipoprotein receptors, without affecting GFAP expression, indicating separate underlying mechanisms. Analysis of the cholesterol biosynthetic pathway revealed that lack of mevalonate and of its downstream metabolites, mainly geranylgeranyl‐pyrophosphate (GGPP), is responsible for the statin‐induced apoptosis of neurons and astrocytes. Moreover, astrocytic stellation triggered by statins was inhibited by mevalonate and GGPP. Interestingly, neuronal cell death was significantly reduced in astrocyte/neuron co‐cultures treated with statins. We postulate that under these conditions signals provided by astrocytes, e.g., isoprenoids play a key role in neuronal survival. © 2006 Wiley‐Liss, Inc.
Health care funding levels and patient outcomes: a national study
Authors: Byrne Margaret M. , Pietz Kenneth , Woodard LeChauncy , Petersen Laura A.
Published: September 2006

Background: Health care funding levels differ significantly across geographic regions, but there is little correlation between regional funding levels and outcomes of elderly Medicare beneficiaries. Our goal was to determine whether this relationship holds true in a non‐Medicare population cared for in a large integrated health care system with a capitated budget allocation system.

Methods: We explored the association between health care funding and risk‐adjusted mortality in the 22 Veterans Affairs (VA) geographic Networks over a six‐year time period. Allocations to Networks were adjusted for illness burden using Diagnostic Cost Groups. To test the association between funding and risk‐adjusted three‐year mortality, we ran logistic regressions with single‐year patient cohorts, as well as hierarchical regressions on a six year longitudinal data set, clustering on VA Network.

Results: A $1000 increase in funding per unit of patient illness burden was associated with a 2–8% reduction in three‐year mortality in cross sectional regressions. However, in longitudinal hierarchical regressions clustering on Network, the significant effect of funding level was eliminated.

Conclusions: When longitudinal data are used, the significant cross sectional effect of funding levels on mortality disappear. Thus, the factors driving differences in mortality are Network effects, although part of the Network effect may be due to past levels of funding. Our results provide a caution for cross sectional examinations of the association between regional health care funding levels and health outcomes. Copyright © 2006 John Wiley & Sons, Ltd.
Incremental distributed modelling investigation in a small agricultural catchment: 1. Overland flow with comparison with the unit hydrograph model
Authors: Taskinen Antti , Bruen Michael
Published: September 2006

A distributed overland flow model is presented and the test results compared with those of the unit hydrograph (UH) model. Infiltration excess in the overland model was calculated using both a modified Green and Ampt (G–A) method and a more complicated method that keeps track of the soil moisture content. The two‐dimensional partial differential flow equations with kinematic flow approximation were solved using both backward‐central explicit and implicit finite‐difference schemes. Moreover, a baseflow component was added to the flow model. Each part of the model was built by replacing a process by a parallel process or by adding a completely new component. When the model was developed and validated in small agricultural fields in southern Finland, comparisons were made between corresponding processes and the significance of added components were estimated in order to find out whether increased model complexity improves the model performance. Apart from the basic model, all the other distributed models outperformed the UH approach. The implicit scheme was clearly more accurate than the explicit scheme, and the baseflow component improved the results significantly. There was no major difference between the performances of the infiltration models, but the G–A method was more stable and much faster. The approaches that were best in the calibration were also the best in the verification. The full distributed model provides a potential method for running water‐quality models and testing their different processes. Copyright © 2006 John Wiley & Sons, Ltd.
Epigenetic salt accumulation and water movement in the active layer of central Yakutia in eastern Siberia
Authors: Lopez C. M. Larry , Brouchkov A. , Nakayama H. , Takakai F. , Fedorov A. N. , Fukuda M.
Published: September 2006

Observations of soil moisture and salt content were conducted from May to August at Neleger station in eastern Siberia. Seasonal changes of salt and soil moisture distribution in the active layer of larch forest (undisturbed) and a thermokarst depression known as an alas (disturbed) were studied. Electric conductivity ECeof the intact forest revealed higher concentrations that increased with depth from the soil surface into the active layer and the underlying permafrost: 1 mS cm−1at 1·1 m, to 2·6 mS cm−1at 160 cm depth in the permafrost. However, a maximum value of 5·4 mS cm−1at 0·6 m depth was found in the dry area of the alas. The concentration of ions, especially Na+, Mg2+, Ca2+, SO42−and HCO3−in the upper layers of this long‐term disturbed site, indicates the upward movement of ions together with water. A higher concentration of solutes was found in profiles with deeper seasonal thawing. The accumulation of salts in the alas occurs from spring through into the growing season. The low concentration of salt in the surface soil layers appears to be linked to leaching of salts by rainfall. There are substantial differences between water content and electric conductivity of soil in the forest and alas. Modern salinization of the active layer in the alas is epigenetic, and it happens in summer as a result of spring water collection and high summer evaporation; the gradual salt accumulation in the alas in comparison with the forest is controlled by the annual balance of water and salts in the active layer. Present climatic trends point to continuous permafrost degradation in eastern Siberia increasing the risk of surface salinization, which has already contributed to changing the landscape by hindering the growth of forest. Copyright © 2006 John Wiley & Sons, Ltd.
Effect of bedrock permeability on subsurface stormflow and the water balance of a trenched hillslope at the Panola Mountain Research Watershed, Georgia, USA
Authors: Tromp‐van Meerveld H. J. , Peters N. E. , McDonnell J. J.
Published: September 2006

The effect of bedrock permeability on subsurface stormflow initiation and the hillslope water balance is poorly understood. Previous hillslope hydrological studies at the Panola Mountain Research Watershed (PMRW), Georgia, USA, have assumed that the bedrock underlying the trenched hillslope is effectively impermeable. This paper presents a series of sprinkling experiments where we test the bedrock impermeability hypothesis at the PMRW. Specifically, we quantify the bedrock permeability effects on hillslope subsurface stormflow generation and the hillslope water balance at the PMRW. Five sprinkling experiments were performed by applying 882–1676 mm of rainfall over a ∼5·5 m × 12 m area on the lower hillslope during ∼8 days. In addition to water input and output captured at the trench, we measured transpiration in 14 trees on the slope to close the water balance. Of the 193 mm day−1 applied during the later part of the sprinkling experiments when soil moisture changes were small, <14 mm day−1 was collected at the trench and <4 mm day−1 was transpired by the trees, with residual bedrock leakage of >175 mm day−1 (91%). Bedrock moisture was measured at three locations downslope of the water collection system in the trench. Bedrock moisture responded quickly to precipitation in early spring. Peak tracer breakthrough in response to natural precipitation in the bedrock downslope from the trench was delayed only 2 days relative to peak tracer arrival in subsurface stormflow at the trench. Leakage to bedrock influences subsurface stormflow at the storm time‐scale and also the water balance of the hillslope. This has important implications for the age and geochemistry of the water and thus how one models this hillslope and watershed. Copyright © 2006 John Wiley & Sons, Ltd.
Evolution study of a regional groundwater system using hydrochemistry and stable isotopes in Songnen Plain, northeast China
Authors: Zhang Guangxin , Deng Wei , Yang Y. S. , Salama R. B.
Published: September 2006

Groundwater is often a critical source of water for municipal, industrial and agricultural uses, especially in arid and semi‐arid environments. Songnen Plain, located in the central part of northeast China, is such a region, it being an important productive base of commodity grain in this country. In the past two decades, groundwater quality in the region, especially salinization, has deteriorated under natural changes and human activities, and has become a crucial factor restricting sustainable eco‐environmental and socio‐economic development. In this paper, The Taoer River catchment, situated in the middle of the region, was selected as the study area for the groundwater quality evolution study using hydrochemistry and stable isotopes to obtain a better understanding of the system. Fifty‐two groundwater samples were collected with systematic design during the low‐water and high‐water periods in 2003. A series of comprehensive quality data interpretations, e.g. statistics, ratios of ions and Piper diagrams, together with stable isotope data, have been used to gain an insight into the spatial and temporal variations and evolution laws of groundwater hydrochemistry. The following main hydrochemical processes were identified as controlling the water quality of the groundwater system: weathering–dissolution, evaporation–condensation, ion‐exchange reactions and groundwater salinization. This latter process, salinization, is the most important process and is caused by the leaching of superficial or near‐surface salts from the saline–alkaline soil into shallow groundwater. Copyright © 2006 John Wiley & Sons, Ltd.
Comparison analysis of the summer monsoon precipitation between northern and southern slopes of Tanggula Mountains, Qinghai–Xizang (Tibetan) Plateau: a case study in summer 1998
Authors: Yang Meixue , Yao Tandong , Gou Xiaohua , Wang Huijun , Hao Lisheng
Published: September 2006

Based on the precipitation data obtained through GEWEX Asian Monsoon Experiment–Tibet fieldwork from May to September 1998, this study investigated the features of the summer monsoon precipitation on the northern and southern slopes of the huge Tanggula Mountains in the Qinghai–Xizang (Tibetan) Plateau. The results show that the precipitation on the southern slope is about 50% higher than on the northern slope, whereas the frequency and diurnal pattern of the precipitation are very similar. The mean precipitation intensity on the southern slope is larger than on the northern slope. In most cases, the daily precipitation showed similar variation on both slopes, demonstrating that the precipitation processes might be similar. In the summer monsoon period, the local convective precipitation contributed to the total precipitation on both slopes and such a contribution on the southern slope is larger. Copyright © 2006 John Wiley & Sons, Ltd.
Tumor–stromal cell interaction under hypoxia increases the invasiveness of pancreatic cancer cells through the hepatocyte growth factor/c‐Met pathway
Authors: Ide Takao , Kitajima Yoshihiko , Miyoshi Atsushi , Ohtsuka Takao , Mitsuno Mayumi , Ohtaka Kazuma , Koga Yasuo , Miyazaki Kohji
Published: September 2006

The hypoxic environment in tumor is reported to play an important role in pancreatic cancer progression. The interaction between stromal and cancer cells also contributes to the malignant behavior of pancreatic cancer. In the present study, we investigated whether hypoxic stimulation affects stromal as well as pancreatic cancer cells. Our findings demonstrated that hypoxia remarkably elevated the HIF‐1α expression in both pancreatic cancer (PK8) and fibroblast cells (MRC5). Hypoxic stimulation accelerated the invasive activity of PK8 cells, and invasiveness was thus further accelerated when the hypoxic PK8 cells were cultured with conditioned medium prepared from hypoxic MRC5 cells (hypoxic conditioned medium). MMP‐2, MMP‐7, MT1‐MMP and c‐Met expressions were increased in PK8 cells under hypoxia. Hypoxic stimulation also increased the hepatocyte growth factor (HGF) secretion from MRC5 cells, which led to an elevation of c‐Met phosphorylation in PK8 cells. Conversely, the elevated cancer invasion, MMP activity and c‐Met phosphorylation of PK8 cells were reduced by the removal of HGF from hypoxic conditioned medium. In immunohistochemical study, the HIF‐1α expression was observed in surrounding stromal as well as pancreatic cancer cells, thus indicating hypoxia exists in both of cancer and stromal cells. Moreover, the stromal HGF expression was found to significantly correlate with not only the stromal HIF‐1α expression but also the c‐Met expression in cancer cells. These results indicate that the hypoxic environment within stromal as well as cancer cells activates the HGF/c‐Met system, thereby contributing to the aggressive invasive features of pancreatic cancer. © 2006 Wiley‐Liss, Inc.
Use of hormone replacement therapy before and after ovarian cancer diagnosis and ovarian cancer survival
Authors: Mascarenhas Chantal , Lambe Mats , Bellocco Rino , Bergfeldt Kjell , Riman Tomas , Persson Ingemar , Weiderpass Elisabete
Published: September 2006

Use of hormone replacement therapy (HRT) has been hypothesized to affect survival of epithelial ovarian cancer (EOC). We studied 5‐year survival in patients with invasive EOC and borderline ovarian tumors (BOT) according to HRT use before and after diagnosis in a prospective nation‐wide cohort study of 799 women diagnosed with EOC (n = 649) and BOT (n = 150) aged 50–74 years in 1993–1995 in Sweden. Cox regression was used to obtain multivariate age‐adjusted hazard ratios (HRs) and 95% confidence intervals (CIs). Multivariate models included indicator variables for age, tumor stage, grade and histological subtype. After 5 years of follow‐up, 45% of the patients with EOC and 93% of the patients with BOT were alive. For women with BOT there were no associations between HRT‐use pre‐ or postdiagnosis and survival. There was no overall difference in 5‐year EOC survival according to use HRT before diagnosis (multivariate HR = 0.83, 95% CI = 0.65–1.08), except for serous EOC (HR = 0.69, 95% CI = 0.48–0.98). Analyses of different HRT preparations, duration and recency of use did not reveal any variations in pattern of survival. We observed a better survival for EOC‐patients who used HRT after diagnosis (multivariate HR = 0.57, 95% CI = 0.42–0.78). We conclude that HRT‐use prior to diagnosis of EOC does not affect 5‐year survival, except for a possible survival advantage in serous EOC. Women using HRT after diagnosis had a better survival than women with no use, but we cannot rule out that this latter finding may reflect a subtle selection process. © 2006 Wiley‐Liss, Inc.
Soluble N‐cadherin in human biological fluids
Authors: Derycke Lara , De Wever Olivier , Stove Veronique , Vanhoecke Barbara , Delanghe Joris , Depypere Herman , Bracke Marc
Published: September 2006

Classical cadherins such as E‐, P‐ and N‐cadherin are transmembrane proteins that mediate cell–cell adhesion, and are important in embryogenesis, maintenance of tissue integrity and cancer. Proteolytic shedding of the extracellular domain results in the generation of soluble E‐, P‐ or N‐cadherin ectodomains. Circulating soluble E‐ and P‐cadherin have been described in the serum, and elevated levels were detected in cancer patients when compared with healthy persons. Here we report the presence of soluble N‐cadherin, a 90‐kD protein fragment, in the serum of both healthy persons and cancer patients, using a direct ELISA and immunoprecipitation. A correlation was found between prostate specific antigen and soluble N‐cadherin, and significantly elevated levels were detected in prostate cancer follow‐up patients. The N‐cadherin protein is neo‐expressed by carcinomas of the prostate, and is responsible for epithelial to fibroblastic transition. This is reflected by the higher concentrations of soluble N‐cadherin in prostate cancer patients than in healthy persons. © 2006 Wiley‐Liss, Inc.
Increased frequencies of CD8+ T lymphocytes recognizing wild‐type p53‐derived epitopes in peripheral blood correlate with presence of epitope loss tumor variants in patients with hepatocellular carcinoma
Authors: Cicinnati Vito R. , Zhang Xia , Yu Zhengya , Ferencik Stanislav , Schmitz Klaus J. , Dworacki Grzegorz , Kaczmarek Elzbieta , Oldhafer Karl , Frilling Andrea , Baba Hideo A. , Schmid Kurt W. , Grosse‐Wilde Hans , Broelsch Christoph E. , DeLeo Albert B. , Gerken Guido , Beckebaum Susanne
Published: September 2006

Wild‐type (WT) sequence p53 peptides are attractive candidates for broadly applicable cancer vaccines. The aim of this study was to evaluate the potential of a WT p53‐based immunotherapeutic approach for patients with hepatocellular carcinoma (HCC). Circulating CD8+ T cells specific for WT p53149–157 and WT p53264–272 HLA‐A*0201 restricted epitopes were directly identified in the peripheral blood by the use of peptide/HLA‐A2.1 tetramers in 24 HCC patients. Cytotoxic T lymphocyte (CTL) activity after WT p53 peptide‐specific stimulation was assessed by analysis of granzyme B and interferon‐gamma mRNA transcription, using a quantitative real‐time polymerase chain reaction assay. Tumor immunophenotyping was performed to evaluate the p53 status, the expression of major histocompatibility complex (MHC) and costimulatory molecules in freshly isolated tumor cells. HCC patients exhibited significantly higher frequencies of WT p53‐specific memory CD8+ T cells and stronger WT p53‐specific CTL activity, when compared with healthy controls. Increased frequencies of p53‐specific CD8+ T cells and their activity correlated with selective HLA‐A2 allele loss and reduced costimulatory molecule expression of tumor cells. Moreover, augmented numbers of p53‐specific T cells coincided with high MHC class II expression in tumor cells but were inversely related to the T status of the tumor node metastasis staging system. Our results indicate the existence of natural immunosurveillance and tumor immune evasion, involving a T cell response against WT p53 tumor antigen in patients with HCC. These findings may have important implications for the future development of cancer vaccines. © 2006 Wiley‐Liss, Inc.
Differential expression and activation of NF‐κB family proteins during oral carcinogenesis: Role of high risk human papillomavirus infection
Authors: Mishra Alok , Bharti Alok C. , Varghese Prishla , Saluja Daman , Das Bhudev C.
Published: September 2006

Oral cancer is one of the most common cancers in India and south‐east Asian region consisting of more than 50% of all malignant tumors. Along with many known risk factors, infection of Human Papillomavirus (HPV) has been associated with the development of oral cancer and is suggested to modulate host cell transcription. Reciprocally, cellular transcription factors, such as NF‐κB and AP‐1 are known to modulate the expression of viral and other genes involved in the development of cancer. In the absence of data on NF‐κB in relation to HPV in oral cancer, we studied the DNA binding activity and expression pattern of NF‐κB family of proteins in different stages of oral cancer and correlated with HPV infection that has been associated with better prognosis of the disease. A total of 110 fresh oral tissue biopsies were collected comprising 10 normal controls, 34 precancer and 66 oral cancer lesions prior to chemotherapy/radiotherapy. Diagnosis of HPV was done by both consensus and type‐specific PCR. Electrophoretic mobility shift assays, western blots and immunohistochemical analysis were performed to assess the binding activity and expression pattern of NF‐κB family of proteins (p50, p65, p52, c‐Rel, RelB and Bcl‐3) in oral tissue biopsies. Twenty seven percent (18/66) of the oral cancer biopsies showed the presence of HPV infection exclusively of high risk HPV type 16, which was primarily associated with the well differentiated squamous cell carcinomas (WDSCC). We observed a high constitutive activation of NF‐κB with concomitant upregulated expression of all the NF‐κB members in oral cancer tissues. Expression of NF‐κB components gradually increased as the severity of lesion increased from precancer to invasive cancer. NF‐κB p50 was found to be the major DNA binding component, which is indicative of homodimerization of p50 subunits. Interestingly, in HPV16 infected oral cancers although p50 showed high binding activity, p65 also showed a partial involvement as evidenced in supershift assay. Both by western blotting and immunohistochemistry, a differential overexpression and nuclear localization of p50, p65 and partially of Bcl‐3 were observed in HPV16 positive oral cancer patients that also showed an over‐expression of p21. We therefore, demonstrate a constitutive activation and differential expression of NF‐κB proteins, which change as a function of severity of oral lesions during development of oral cancer. The NF‐κB DNA binding is primarily due to homodimerization of p50 but infection of high risk HPV promotes participation of p65 in NF‐κB complex formation, leading to heterodimerization of p50/p65. We propose that the involvement of p65 in HPV infected oral cancer may be linked to improved differentiation and better prognosis of the disease when treated. © 2006 Wiley‐Liss, Inc.
Melanoma cells interfere with the interaction of dendritic cells with NK/LAK cells
Authors: Capobianco Annalisa , Rovere‐Querini Patrizia , Rugarli Claudio , Manfredi Angelo A.
Published: September 2006

Dendritic cells (DCs) and natural killer (NK) cells are key players at the interface between innate resistance and acquired immunity. NK cells can induce DC maturation, a differentiation process whereby DCs respond to a environmental stimulus and acquire the ability of eliciting adaptive immunity. Conversely, maturing DCs promote NK functions in vivo and in vitro. This interplay has important consequences on the immune response to pathogens and possibly to neoplastic cells. Here, we show that B16 melanoma cells actively modulate the interaction between DCs derived from bone marrow precursors and NK/LAK cells propagated from the spleen of C57BL/6 mice. DCs increased in a dose‐dependent manner the ability of NK/LAK cells to kill melanoma cells and to produce cytokines. This activatory cross‐talk entailed the production of IL‐18 by DCs and of IFN‐γ by NK/LAK cells. Melanoma cells were not a passive target of NK activity; they regulated the outcome of the interaction between DCs and NK/LAK cells, inhibiting the in vitro production of cytokines as effectively as the genetic deletion of IL‐18 or IFN‐γ. Interference with the NK/DC interaction possibly represents a mechanism used by growing tumors to evade the immune response. © 2006 Wiley‐Liss, Inc.
Prostaglandin E2 protects human lung fibroblasts from cigarette smoke extract‐induced apoptosis via EP2 receptor activation
Authors: Sugiura Hisatoshi , Liu Xiangde , Togo Shinsaku , Kobayashi Tetsu , Shen Lei , Kawasaki Shin , Kamio Koichiro , Wang Xing Qi , Mao Li Jun , Rennard Stephen I.
Published: September 2006

Prostaglandin E2 (PGE2) has been shown to have a strong cytoprotective effect, inhibiting apoptosis. In the present study, we evaluated whether PGE2 has a protective effect on cigarette smoke extract (CSE)‐induced apoptosis in human lung fibroblasts. Apoptosis was assessed by various methods, including DNA content analysis. CSE (15%–20%) led to apoptosis and induced imbalance in favor of pro‐ over anti‐apoptotic protein expression and activated caspases. PGE2 blocked CSE‐induced apoptosis and modulated the balance of pro‐ and anti‐apoptotic proteins and decreased the activation of caspases. This anti‐apoptotic effect was mediated via EP2 receptor activation as the EP2 agonist butaprost mimicked PGE2 activity and siRNA for the EP2 receptor blocked it. An adenylyl cyclase inhibitor was found to abolish the PGE2‐mediated cytoprotective effect. Correspondingly, c‐AMP analogs blocked CSE‐induced apoptosis. Consistently, the protein kinase A (PKA) inhibitor KT‐5720 abolished PGE2‐mediated protection. PGE2 and butaprost phosphorylated Bad and KT‐5720 blocked phosphorylation. These results suggest that PGE2 inhibits CSE‐induced apoptosis via EP2 receptor activation and activation of PKA, which leads to an alteration in the balance between pro‐ and anti‐apoptotic factors. Through such a mechanism, PGE2 may alter survival of cells in the smoke‐exposed lungs, thus affecting the pathogenesis of cigarette smoke‐induced disease. J. Cell. Physiol. 210: 99–110, 2007. © 2006 Wiley‐Liss, Inc.
Cyclophilin C‐associated protein is up‐regulated during wound healing
Authors: Kong Wuyi , Li Shaowei , Longaker Michael T. , Lorenz H. Peter
Published: September 2006

Cyclophilin C‐associated protein (CyCAP) is identified from macrophages. It locates in intracellular, membrane bound and extracellular, suggesting it has an important role, however both of its regulation and function have not been elucidated. The expression of CyCAP in skin and during wound healing is also unknown. We demonstrate that CyCAP is expressed in both dermal fibroblasts and keratinocytes. In the dermis, the majority of CyCAP protein is located intracellular in a filamentous protein form while a lesser amount is in the extracellular matrix (ECM). CyCAP gene and protein expression is increased 1 day after skin wound healing in both fetal and adult rats and remains elevated level up to 1 week in adult rats. Immunohistochemistry studies demonstrate that the increased CyCAP expression locates mainly to inflammatory cells, including macrophages, monocytes and lymphocytes during wound healing. Interferon‐γ increases CyCAP gene and protein expression in cultured rat fibroblasts. We also found that wound healing is slower and less collagen is expressed in skin of CyCAP null mice. These data are the first observations of CyCAP expression in skin and during wound repair. Our data indicates that CyCAP is regulated by IFNγ and may function on immune defense in macrophages, lymphocytes, dermal fibroblasts and keratinocytes during wound healing. J. Cell. Physiol. 210: 153–160, 2007. © 2006 Wiley‐Liss, Inc.
Immunohistochemical analysis of pRb2/p130, VEGF, EZH2, p53, p16INK4A, p27KIP1, p21WAF1, Ki‐67 expression patterns in gastric cancer
Authors: Mattioli Eliseo , Vogiatzi Paraskevi , Sun Ang , Abbadessa Giovanni , Angeloni Giulia , D'Ugo Domenico , Trani Daniela , Gaughan John P. , Vecchio Fabio Maria , Cevenini Gabriele , Persiani Roberto , Giordano Antonio , Claudio Pier Paolo
Published: September 2006

Although the considerable progress against gastric cancer, it remains a complex lethal disease defined by peculiar histological and molecular features. The purpose of the present study was to investigate pRb2/p130, VEGF, EZH2, p53, p16INK4A, p27KIP1, p21WAF1, Ki‐67 expressions, and analyze their possible correlations with clinicopathological factors. The expression patterns were examined by immunohistochemistry in 47 patients, 27 evaluated of intestinal‐type, and 20 of diffuse‐type, with a mean follow up of 56 months and by Western blot in AGS, N87, KATO‐III, and YCC‐2, ‐3, ‐16 gastric cell lines. Overall, stomach cancer showed EZH2 correlated with high levels of p53, Ki‐67, and cytoplasmic pRb2/p130 (P < 0.05, and P < 0.01, respectively). Increased expression of EZH2 was found in the intestinal‐type and correlated with the risk of distant metastasis (P < 0.05 and P < 0.01, respectively), demonstrating that this protein may have a prognostic value in this type of cancer. Interestingly, a strong inverse correlation was observed between p27KIP1 expression levels and the risk of advanced disease and metastasis (P < 0.05), and a positive correlation between the expression levels of p21WAF1 and low‐grade (G1) gastric tumors (P < 0.05), confirming the traditionally accepted role for these tumor‐suppressor genes in gastric cancer. Finally, a direct correlation was found between the expression levels of nuclear pRb2/p130 and low‐grade (G1) gastric tumors that was statistically significant (P < 0.05). Altogether, these data may help shed some additional light on the pathogenetic mechanisms related to the two main gastric cancer histotypes and their invasive potentials. J. Cell. Physiol. 210: 183–191, 2007. © 2006 Wiley‐Liss, Inc.
Heme oxygenase and cyclooxygenase in the central nervous system: A functional interplay
Authors: Mancuso Cesare , Perluigi Marzia , Cini Chiara , De Marco Carlo , Giuffrida Stella Anna Maria , Calabrese Vittorio
Published: September 2006

Heme oxygenase (HO) and cyclooxygenase (COX) are two hemeproteins involved in the regulation of several functions in the nervous system. Heme oxygenase is the enzyme responsible for the degradation of heme into ferrous iron, carbon monoxide (CO), and biliverdin, the latter being further reduced in bilirubin (BR) by biliverdin reductase. Heme oxygenase‐derived CO is a gaseous neuromodulator and plays an important role in the synaptic plasticity, learning and memory processes, as well as in the regulation of hypothalamic neuropeptide release, whereas BR is an endogenous molecules with antioxidant and anti‐nitrosative activities. Cyclooxygenase is considered a pro‐inflammatory enzyme as free radicals and prostaglandins (PGs) are produced during its catalytic cycle. Although PGs are also involved in a variety of physiologic conditions including angiogenesis, hemostasis, or regulation of kidney function, upregulation of COX and increase in PGs levels are a common feature of neuroinflammation. In the brain, a functional interplay exists between HO and COX. Heme oxygenase regulates COX activity by reducing the intracellular heme content or by generating CO, which stimulates PGE2 release. Increased levels of PGs, free radicals, and the associated oxidative stress serve in the brain as a trigger for the induction of HO isoforms which increases cellular antioxidant defenses to counteract oxidative damage. The importance of the interaction between HO and COX in the regulation of physiologic brain functions, and its relevance to neuroprotective or neurodegenerative mechanisms are discussed. © 2006 Wiley‐Liss, Inc.
Antiinflammatory but no neuroprotective effects of melatonin under clinical treatment conditions in rabbit models of bacterial meningitis
Authors: Spreer Annette , Gerber Joachim , Baake Daniel , Hanssen Mareike , Huether Gerald , Nau Roland
Published: September 2006

Neuronal injury is frequent in bacterial meningitis, resulting in a high rate of death and neurological sequelae. In a search of potential neuroprotective strategies for treatment of bacterial meningitis, the antioxidant melatonin was neuroprotective in cell culture experiments and in a rabbit Streptococcus pneumoniae meningitis model, when treatment was started at the time of infection. In the present study, adjunctive melatonin treatment applied from the beginning of antibiotic therapy 12 hr after infection at a dose of 1.67 mg/kg/hr resulted in plasma concentrations of 451 ± 198 ng/ml, cerebrospinal fluid (CSF) concentrations of 154 ± 57 ng/ml and a CSF‐to‐plasma ratio of 0.38 ± 0.19 (mean ± SD). Melatonin therapy had antiinflammatory effects but did not reduce neuronal injury in either a rabbit model of gram‐positive Streptococcus pneumoniae or gram‐negative Escherichia coli meningitis. © 2006 Wiley‐Liss, Inc.
Intravenous administration of glial cell line‐derived neurotrophic factor gene‐modified human mesenchymal stem cells protects against injury in a cerebral ischemia model in the adult rat
Authors: Horita Yoshifumi , Honmou Osamu , Harada Kuniaki , Houkin Kiyohiro , Hamada Hirofumi , Kocsis Jeffery D.
Published: September 2006

Intravenous administration of human mesenchymal stem cells (hMSCs) prepared from adult bone marrow has been reported to ameliorate functional deficits after cerebral artery occlusion in rats. Several hypotheses to account for these therapeutic effects have been suggested, and current thinking is that neuroprotection rather than neurogenesis is responsible. To enhance the therapeutic benefits of hMSCs potentially, we transfected hMSCs with the glial cell line‐derived neurotrophic factor (GDNF) gene using a fiber‐mutant F/RGD adenovirus vector and investigated whether GDNF gene‐modified hMSCs (GDNF‐hMSCs) could contribute to functional recovery in a rat permanent middle cerebral artery occlusion (MCAO) model. We induced MCAO by using intraluminal vascular occlusion, and GDNF‐hMSCs were intravenously infused into the rats 3 hr later. MRI and behavioral analyses revealed that rats receiving GDNF‐hMSCs or hMSCs exhibited increased recovery from ischemia compared with the control group, but the effect was greater in the GDNF‐hMSC group. Thus, these results suggest that intravenous administration of hMSCs transfected with the GDNF gene using a fiber‐mutant adenovirus vector may be useful in the cerebral ischemia and may represent a new strategy for the treatment of stroke. © 2006 Wiley‐Liss, Inc.
Cerebellar modulation of feeding‐related neurons in rat dorsomedial hypothalamic nucleus
Authors: Zhu Jing‐Ning , Li Hong‐Zhao , Ding Yi , Wang Jian‐Jun
Published: September 2006

Cerebellum has newly been implicated in many more nonsomatic functions other than motor control. Previous studies indicate that the cerebellum is involved in feeding regulation and that the gastric vagal nerves transmit short‐term meal‐related visceral signals, including cholecystokinin (CCK), into the hypothalamus. Recently, the dorsomedial hypothalamic nucleus (DMN) has been thought to play an important role in feeding control. Here we investigate whether the inputs from cerebellar interpositus nucleus (IN) can reach and converge onto single DMN neurons with some feeding‐related visceral signals, including gastric vagal inputs, CCK, and blood glucose, whose concentration is closely linked to food intake. Among the 259 DMN neurons recorded, 120 (46.3%) and 169 (65.3%) responded to the cerebellar IN and gastric vagal stimulations, respectively. Within the 120 DMN neurons responsive to the cerebellar IN stimulation, 98 (81.7%) also responded to the gastric vagal stimulus, and a summation of the responses was observed further (n = 20), suggesting a convergence and interaction of cerebellar and gastric vagal inputs on the cells. Moreover, among the 98 cells receiving convergent inputs from cerebellar IN and gastric vagal nerves, 69 (70.4%) were identified to be glycemia sensitive, and 22 (68.8%) of the 32 tested neurons were also sensitive to systemic CCK. These results demonstrate that the DMN integrates somatic information forwarded by the cerebellar IN and visceral signals related to food intake, including gastric vagal, CCK and glycemia, and electrophysiologically reveal a novel cerebellohypothalamic IN‐DMN pathway through which the cerebellum may actively participate in short‐term feeding regulation. © 2006 Wiley‐Liss, Inc.
Ectopic expression of phospho‐Smad2 in Alzheimer's disease: Uncoupling of the transforming growth factor‐β pathway?
Authors: Lee Hyoung‐gon , Ueda Masumi , Zhu Xiongwei , Perry George , Smith Mark A.
Published: September 2006

Transforming growth factor‐β (TGF‐β), a multifunctional cytokine, has been widely suggested to play a role in the pathogenesis of Alzheimer's disease. Supporting this, levels of TGF‐β are elevated in the cerebrospinal fluid, sera, and brain of patients with Alzheimer's disease. Since TGF‐β is neuroprotective, whereas Alzheimer's disease is typified by neurodegeneration, we speculated that defects in TGF‐β signaling might abrogate its neuroprotective properties. Consistently with an increase in TGF‐β in Alzheimer's disease, we found significant increases in phospho‐Smad2, a major downstream signaling molecule of TGF‐β, in hippocampal neurons of Alzheimer's disease compared with age‐matched control patients. However, in contrast to an expected nuclear localization, phosphorylated Smad2 in Alzheimer's disease was predominantly, and ectopically, found in the neuronal cytoplasm, specifically colocalized with neurofibrillary tangles and granulovacuolar degeneration. Given that a nuclear localization is required to regulate the transcription of TGF‐β target genes to afford neuroprotection, the ectopic localization of phosphorylated Smad2 suggests a defect in the Smad‐mediated signaling pathway of TGF‐β in Alzheimer's disease and consequent loss of neuroprotective function. © 2006 Wiley‐Liss, Inc.
A high‐resolution multi‐proxy stalagmite record from Mechara, Southeastern Ethiopia: palaeohydrological implications for speleothem palaeoclimate reconstruction
Authors: Asrat Asfawossen , Baker Andy , Mohammed Mohammed Umer , Leng Melanie J. , Calsteren Peter Van , Smith Claire
Published: September 2006

An annually laminated stalagmite from Southeastern Ethiopia grew for 443±8 yr starting at 5023 yr BP (±160 yr) as determined by lamina‐tuned U‐Th dating. The speleothem shows three growth phases: (1) an initial phase where the stalagmite has a candlestick shape, deposited by relatively slow rate drip water; (2) a middle growth phase where laminae grow on the flanks, suggesting faster drip rates; and (3) a final growth phase where the speleothem becomes narrower owing to a decrease in drip water supply towards the end of deposition. Morphometry, annual growth rate, fluorescence index, and 234U/238U isotope ratio show marked differences between the growth phases, while δ13C and δ18O do not show significant variation, except within the third phase towards the top of the stalagmite, where they have higher values. The study indicates that the multiproxy approach is crucial as the different proxies respond to single climate forcing in different manners. Our results can be widely applied to speleothem studies distinguishing the relative importance of the various proxies in recording cave ‘external’ (climate, hydrology) and cave ‘internal’ (e.g. evaporation) processes. Copyright © 2006 John Wiley & Sons, Ltd.
Concentrated Fe(III)–nitrilotriacetate solutions: study by Raman spectroscopy and ab initio calculations
Authors: Loridant Stéphane , Digne Mathieu , Daniel Marlène , Huard Thierry
Published: September 2006

Fe(III)–nitrilotriacetate(NTA) aqueous solutions are used in various redox desulfurization processes. The nature of stable Fe–NTA complexes depends highly on parameters such as [Fe(III)] concentration, NTA/Fe ratio and pH value. These complexes can be characterized by potentiometric measurements or UV‐vis spectroscopy, but only at rather low concentrations. Using synthesis of solids, Raman spectra of these solids and ab initio calculations, a rational determination of the nature of complexes stable in water at high iron concentrations was proposed from the position sensitivity of the main low wavenumber band to the coordination sphere of iron cations. This band was assigned to ν(FeN) stretching vibrations from ab initio calculations. Depending on the pH and NTA/Fe ratio of the prepared solutions, different species were identified from the Raman spectra. The present methodology can be extended to other metal–ligand systems to elucidate the nature of stable complexes in aqueous solution. Copyright © 2006 John Wiley & Sons, Ltd.
Phase transition and stability of thiourea:diethyloxalate (2:1) complex
Authors: Sakuntala T. , Chitra R. , Rao Rekha , Thomas S. , Venkateswaran Sugandhi , Choudhury R. R. , Tyagi A. K. , Deb S. K.
Published: September 2006

The Raman spectrum of the crystalline complex thiourea:diethyloxalate (2:1) is reported. The Raman wavenumbers in the complex are compared with those of crystalline thiourea (TU) and diethyloxalate (DEO), and the observed differences are understood from the point of view of the hydrogen bonding in the system. From the wavenumbers of the NH stretching vibrations, it is inferred that the strengths of hydrogen bonds in the complex are smaller compared to those in TU. The evolution of the Raman spectrum at high temperature reveals that the NH··· O hydrogen bonds, which are a key to the formation of the complex, are broken above 397 K. The spectrum corresponding to the crystalline complex reappears below 375 K when cooled from temperatures below melting. Copyright © 2006 John Wiley & Sons, Ltd.
Simulation of Rayleigh waves in cracked plates
Authors: Cao M. T. , Moreno C. , Quintela P.
Published: September 2006

The aim of this paper is to develop new numerical procedures to detect micro cracks, or superficial imperfections, in thin plates using excitation by Rayleigh waves. We shall consider a unilateral contact problem between the two sides of the crack in an elastic plate subjected to suitable boundary conditions in order to reproduce a single Rayleigh wave cycle.

An approximate solution of this problem will be calculated by using one of the Newmark methods for time discretization and a finite element method for space discretization. To deal with the nonlinearity due to the contact condition, an iterative algorithm involving one multiplier will be used; this multiplier will be approximated by using Newton's techniques.

Finally, we will show numerical simulations for both cracked and non‐cracked plates. Copyright © 2006 John Wiley & Sons, Ltd.