bluuebunny/crossref_metadata_2025_split huggingface dataset:
Wetlands with controlled drainage and sub‐irrigation systems—modelling of the water balance
Authors: Dietrich Ottfried , Redetzky Michael , Schwärzel Kai 
Published: December 2006

AbstractOver the past centuries, the agricultural use of wetlands in Central Europe has required interference with the natural wetland water balance. Often this has consisted of drainage measures alone. In low‐precipitation areas, it has also involved the operation of combined drainage and sub‐irrigation systems. Model studies conducted as part of planning processes, or with a view to finding out the impact of changing climate conditions on the water balance of wetlands, must take these facts into account. For this reason, a water balance model has been devised for wetlands whose water balance is governed by water resources management systems. It is based on the WBalMo model system. Special modules were integrated into WBalMo to calculate the water balance of wetland areas (WABI module) and to regulate inflow partitioning within the wetland (REGINF module). When calculating the water balance, the WABI module takes into account precipitation and potential evapotranspiration, groundwater levels below surface, soil types, land‐use classes, inflows via the running water system, and data for target water levels. It provides actual evapotranspiration, discharge into the running water system, and groundwater levels in the area.The example of the Spreewald, a major wetland area in north‐eastern Germany, was used to design and test the WBalMo Spreewald model. The comparison of measured and calculated water balance parameters of the wetland area confirms the suitability of the model for water balance studies in wetlands with complex water resources management systems. The results reveal the strong influence of water management on the water balance of such areas. The model system has proved to be excellently suited for planning and carrying out water management measures aimed at the sustainable development of wetlands. Furthermore, scenario analyses can be used to assess the impact of global change on the water balance of wetlands. Copyright © 2006 John Wiley & Sons, Ltd.
Carnosic acid from rosemary extracts: a potential chemoprotective agent against aflatoxin B1. An in vitro study
Authors: Costa Stefano , Utan Anelì , Speroni Ester , Cervellati Rinaldo , Piva Gianfranco , Prandini Aldo , Guerra Maria Clelia 
Published: December 2006

AbstractSince oxidative stress plays an important role in the toxicity mechanism of several mycotoxins such as aflatoxin B1 (AFB1), the use of natural or synthetic free radical scavengers could be a potential chemopreventive strategy. Carnosic acid (CA) is the major polyphenolic compound present in rosemary plants and it can also be found in sage leaves. Its free radical scavenging properties were tested with two chemical methods. It was found that it has good free radical scavenging capacity at pH 7.4. This study also found that a 24 h pre‐treatment with 10, 20 and 30 μm CA led to a clear, dose‐dependent protective effect on cell toxicity, reducing cell death induced by a 24 h exposure with 10 μm AFB1, respectively, by 16% (P < 0.05), 26% (P < 0.01) and 63% (P < 0.001). It was also found that a 24 h pre‐treatment with 20 and 30 μm CA achieved a reduction of ROS levels, respectively, of 146% (P < 0.001) and 173% (P < 0.001) in HepG2 cells exposed to 10 μm AFB1 for 8 h. Moreover, in cells pre‐incubated with 30 μm CA for 24 h the concentration of 8‐OH‐deoxyguanine decreased by 57% (P < 0.001) with respect to the cells exposed for 24 h to 10 μm AFB1 alone. The results obtained with the in vitro and chemical studies support the theory that AFB1 induced oxidative stress plays an important role in the cytotoxic mechanism of this mycotoxin. Furthermore these findings suggest a starting point for developing alimentary strategies in order to counteract the damage caused by AFB1 contamination in feed and food. Copyright © 2006 John Wiley & Sons, Ltd.
Injecting partially digested cartilage fragments into a biphasic scaffold to generate osteochondral composites in a nude mice model
Authors: Liao Chun‐Jen , Lin Yu‐Ju , Chiang Hongsen , Chiang Shu‐Fang , Wang Yao‐Horng , Jiang Ching‐Chuan 
Published: December 2006

AbstractThis study proposed a novel scaffold with heterogeneous morphology that mimics the natural tissue. Its upper part contains a hollow cavity surrounded by a wall of poly(L‐lactic‐co‐glycolic acid) (PLGA) porous membrane for injecting cartilage tissue and cells. An interconnecting porous structure located under the hollow cavity was made of composite materials that combined PLGA and β‐tricalcium phosphate (β‐TCP) to simulate the subchondral bone. Adult pig articular cartilage was cut and sieved into small fragments. The tissue fragments was partially digested by 0.1% collagenase for 0, 2, 4, and 6 h and injected into the hollow cavity of the biphasic scaffold. The biphasic scaffolds were then implanted into the subcutaneous pocket of nude mice for 4 weeks. No tissue bonding or new cartilaginous tissue formation was identified in the cartilage fragment without enzymatic treatment. The cartilage fragments digested with 2 h of collagenase digestion were partially integrated after implantation. The integrative properties of the cartilage fragment depended on the extent of enzymatic digestion. Releasing cells at the tissue surface enhanced confluence and bonding of the cartilage fragment matrix. Complete integration of the cartilage fragments and cartilage remodeling were achieved by digestion of the tissue fragments with 4 h of enzymatic treatment. The neocartilage grew from the upper hollow cavity into the lower PLGA/β‐TCP porous structure, forming an interface similar to that formed between cartilage and subchondral bone. This study combined the osteochondral scaffold and limited cartilage tissues to generate cartilage tissue in vivo intending for repairing full‐thickness articular cartilage defects. © 2006 Wiley Periodicals, Inc. J Biomed Mater Res, 2007
Targeting microspheres and cells to polyethylene glycol‐modified biological surfaces
Authors: Deglau Timothy E. , Johnson Jermaine D. , Villanueva Flordeliza S. , Wagner William R. 
Published: December 2006

AbstractIt has previously been demonstrated that damaged arterial tissue can be acutely modified with protein‐reactive polyethylene glycol (PEG) to block undesirable platelet deposition. This concept might be expanded by employing PEG‐biotin and its strong interaction with avidin for site‐specific targeted delivery. Toward this end, cultured endothelial cells (ECs) were surface modified with PEG‐biotin and the available biotin was quantified with flow cytometry. NeutrAvidin‐coated microspheres and PEG‐biotin modified ECs with NeutrAvidin as a bridging molecule were delivered under arterial shear stress to PEG‐biotin modified ECs on a coverslip as well as scrape‐damaged bovine carotid arteries. After incubation with a 10 mM solution for 1 min, 8 × 107 PEG‐biotin molecules/EC were found and persisted for up to 120 h. Perfused microspheres adhered to NHS‐PEG‐biotin treated bovine carotid arteries with 60 ± 16 microspheres/mm2 versus 11 ± 4 microspheres/mm2 for control arteries (p < 0.015). Similarly, 22 ± 5 targeted ECs/mm2 adhered to NHS‐PEG‐biotin treated bovine carotid arteries versus 6 ± 2 ECs/mm2 for control arteries (p < 0.01). The targeting strategy demonstrated here might ultimately find application for drug delivery, gene therapy, or cell therapy where localization to specific labeled vascular regions is desired following catheter‐based or surgical procedures. © 2006 Wiley Periodicals, Inc. J Biomed Mater Res 2006
Synthesis and properties of cyclic acetal biomaterials
Authors: Moreau Jennifer L. , Kesselman Dafna , Fisher John P. 
Published: December 2006

AbstractThere is an increasing need to develop new biomaterials as tissue engineering scaffolds. Unfortunately, many of the materials that have been studied for these purposes are polyesters that hydrolytically degrade into acidic products, which may harm the surrounding tissue, and lead to accelerated degradation of the biomaterial. To overcome this disadvantage, a novel class of biomaterials based on a cyclic acetal unit has been created. Specifically, materials based upon the monomer 5‐ethyl‐5‐(hydroxymethyl)‐β,β‐dimethyl‐1,3‐dioxane‐2‐ethanol diacrylate (EHD) is examined. This study investigates the effects of fabrication parameters, including initiator content, volume of diluent, and volume of accelerant, on several properties of EHD networks. Twelve different formulations were fabricated by varying the three parameters in a factorial design. The effects of the fabrication parameters on properties of the EHD networks were examined. Results show that the volume of accelerant most affected the EHD network gelation time, while the volume of diluent most affected the maximum reaction temperature, sol fraction, and degree of swelling. Cell viability on the EHD networks varied between (18 ± 6)% and (57 ± 10)% of the control at 4 h, and between (36 ± 14)% and (140 ± 50)% of the control at 8 h. These results indicate that it is possible to control the properties of the EHD networks by varying the fabrication parameters, and that EHD networks support a viable cell population. © 2006 Wiley Periodicals, Inc. J Biomed Mater, 2007
Inhibitory effect of TNF‐α on the intestinal absorption of galactose
Authors: Amador P. , García‐Herrera J. , Marca M.C. , de la Osada J. , Acín S. , Navarro M.A. , Salvador M.T. , Lostao M.P. , Rodríguez‐Yoldi M.J. 
Published: December 2006

AbstractSepsis is a systemic response to infection in which toxins, such as bacterial lipopolysaccharide (LPS), stimulate the production of inflammatory mediators like the cytokine tumor necrosis factor alpha (TNF‐α). Previous studies from our laboratory have revealed that LPS inhibits the intestinal absorption of L‐leucine and D‐fructose in rabbit when it was intravenously administered, and that TNF‐α seems to mediate this effect on amino acid absorption. To extend this work, the present study was designed to evaluate the possible effect of TNF‐α on D‐galactose intestinal absorption, identify the intracellular mechanisms involved and establish whether this cytokine mediates possible LPS effects. Our findings indicate that TNF‐α decreases D‐galactose absorption both in rabbit intestinal tissue preparations and brush‐border membrane vesicles. Western blot analysis revealed reduced amounts of the Na+/glucose cotransporter (SGLT1) protein in the plasma membrane attributable to the cytokine. On the contrary, TNF‐α increased SGLT1 mRNA levels. Specific inhibitors of the secondary messengers PKC, PKA, the MAP kinases p38 MAP, JNK, MEK1/2 as well as the proteasome, diminished the TNF‐α‐evoked inhibitory effect. LPS inhibition of the uptake of the sugar was blocked by a TNF‐α antagonist. In conclusion, TNF‐α inhibits D‐galactose intestinal absorption by decreasing the number of SGLT1 molecules at the enterocyte plasma membrane through a mechanism in which several protein‐like kinases are involved. J. Cell. Biochem. 101: 99–111, 2007. © 2006 Wiley‐Liss, Inc.
Role of PKA in the anti‐Thy‐1 antibody‐induced neurite outgrowth of dorsal root ganglionic neurons
Authors: Chen Chien‐Hsing , Chen Yi‐Jen , Jeng Chung‐Jiuan , Yang Shih‐Hung , Tung Po‐Yuan , Wang Seu‐Mei 
Published: December 2006

AbstractThy‐1 is highly expressed in the mammalian nervous system. Our previous study showed that addition of anti‐Thy‐1 antibody to cultured dorsal root ganglionic (DRG) neurons promotes neurite outgrowth. In this study, we identified a novel signaling pathway mediating this event. Treatment with function‐blocking anti‐Thy‐1 antibodies enhanced neurite outgrowth of DRG neurons in terms of total neurite length, longest neurite length, and total neurite branching points. To elucidate the possible signal transduction pathway involved, activation of kinases was evaluated by Western blotting. Transient phosphorylation of protein kinase A (PKA) and mitogen‐activated kinase kinase (MEK) was induced after 15 min of anti‐Thy‐1 antibody treatment. Pretreatment with a PKA inhibitor (PKI) or an MEK inhibitor, PD98059, significantly decreased the neurite outgrowth response triggered by anti‐Thy‐1 antibody, indicating the involvement of both kinases. In addition, anti‐Thy‐1 antibody treatment also induced transient phosphorylation of cyclic AMP‐response element‐binding protein (CREB) and this effect was also blocked by a PKI or PD98059. Furthermore, the fact that PKI abolished anti‐Thy‐1 antibody‐induced MEK phosphorylation showed that PKA acts upstream of the MEK‐CREB cascade. In summary, the PKA‐MEK‐CREB pathway is a new pathway involved in the neurite outgrowth‐promoting effect of anti‐Thy‐1 antibody. J. Cell. Biochem. 101: 566–575, 2007. © 2006 Wiley‐Liss, Inc.
Morphological changes in mouse embryos cryopreserved by different techniques
Authors: Coutinho A.R.S. , Mendes C.M. , Caetano H.V.A. , Nascimento A.B. , Oliveira V.P. , Hernadez‐Blazquez F.J. , Sinhorini I.L. , Visintin J.A. , Assumpção M.E.O. 
Published: December 2006

AbstractCryopreservation of mammalian embryos is an important tool for the application of reproductive biotechnologies. Subjective evaluation to determine embryo viability is often used. The determination of the best cryopreservation protocol depends on morphological and molecular analysis of cellular injuries. The main objective of this study was to compare two methods of cryopreservation by assessing morphological alterations of frozen embryos using light, fluorescence, and transmission electron microscope. Fresh (control), slow frozen, and vitrified mouse embryos were composed. To evaluate the viability of the embryos, the cell membrane integrity was assessed using Hoechst33342 and propidium iodide (H/PI) staining. Morphological analyses using hematoxylin and eosin (HE) staining were performed to test different techniques (in situ, paraffin, and historesin) by both light and fluorescence microscopy. Transmission electron microscope was used to detect ultrastructural alterations in Spurr‐ and Araldite‐embedded samples. H/PI staining detected more membrane permeability in the vitrification (69.8%) than in the slow freezing (48.4%) or control (13.8%) groups (P < 0.001). Historesin‐embedded samples showed to be more suitable for morphological analyses because cellular structures were better identified. Nuclear evaluation in historesin sections showed the induction of pycnosis in slow freezing and vitrification groups. Cytoplasm evaluation revealed a condensation and an increase in eosinophilic intensity (indicating apoptosis) in the slow freezing group, and weakly eosinophilic structures and degenerated cells (indicating oncosis) in the vitrification group (P < 0.05). Ultrastructural analyses confirmed HE morphological findings. It was concluded that both cryopreservation techniques resulted in oncosis and apoptosis injuries. However, vitrification caused more severe cellular alterations and reduced embryonic viability compared to slow freezing. Microsc. Res. Tech., 2007. © 2006 Wiley‐Liss, Inc.
Simultaneous diagonal flips in plane triangulations
Authors: Bose Prosenjit , Czyzowicz Jurek , Gao Zhicheng , Morin Pat , Wood David R. 
Published: December 2006

AbstractSimultaneous diagonal flips in plane triangulations are investigated. It is proved that every triangulation with n ≥ 6 vertices has a simultaneous flip into a 4‐connected triangulation, and that the set of edges to be flipped can be computed in $\cal O$(n) time. It follows that every triangulation has a simultaneous flip into a Hamiltonian triangulation. This result is used to prove that for any two n‐vertex triangulations, there exists a sequence of $\cal O$(logn) simultaneous flips to transform one into the other. Moreover, Ω(log n) simultaneous flips are needed for some pairs of triangulations. The total number of edges flipped in this sequence is $\cal O$(n). The maximum size of a simultaneous flip is then studied. It is proved that every triangulation has a simultaneous flip of at least ${{1}\over{3}}({n}-{2})$ edges. On the other hand, every simultaneous flip has at most n − 2 edges, and there exist triangulations with a maximum simultaneous flip of ${{6}\over{7}}({n}-{2})$ edges. © 2006 Wiley Periodicals, Inc. J Graph Theory 54: 307–330, 2007
New approach for rapid detection of known hemoglobin variants using LC‐MS/MS combined with a peptide database
Authors: Basilico F. , Di Silvestre D. , Sedini S. , Petretto A. , Levreri I. , Melioli G. , Farina C. , Mori F. , Mauri P. L. 
Published: December 2006

AbstractThe identification of hemoglobin (Hb) variants is usually performed by means of different analytical steps and methodologies. Phenotypic methods, such as gel electrophoresis and high performance liquid chromatography, are used to detect the different electrophoretic or chromatographic behaviors of hemoglobin variants in comparison to HbA0 used as a control. These data often need to be combined with mass spectrometry analyses of intact globins and their tryptic peptide mixtures. As an alternative to a ‘step‐by‐step’ procedure, we have developed a ‘single step’ approach for the identification of Hb variants present in biological samples. This is based on the µHPLC‐ESI‐MS/MS analysis of the peptide mixture generated by a tryptic digestion of diluted Hb samples and an in‐house new database containing solely the variant tryptic peptide of known human Hb variants. The experimental results (full MS and MS/MS spectra) are correlated with theoretical mass spectra generated from our in‐house‐built variant peptide database (Hbp) using the SEQUEST algorithm. Simple preparation of samples and an automated identification of the variant peptide are the main characteristics of this approach, making it an attractive method for the detection of Hb variants at the routine clinical level. We have analyzed 16 different samples, each containing a different known variant of hemoglobin. Copyright © 2006 John Wiley & Sons, Ltd.
Human herpesvirus 8: Serovprevalence and correlates in tumor patients from Xinjiang, China
Authors: He Fangping , Wang Xing , He Bin , Feng Zongdi , Lu Xiaomei , Zhang Yaoxin , Zhao Shujun , Lin Renyong , Hui Yan , Bao Yongxing , Zhang Zhaoxia , Wen Hao 
Published: December 2006

AbstractHuman herpesvirus 8 (HHV‐8), also known as Kaposi's sarcoma‐associated herpesvirus, is etiologically associated with Kaposi's sarcoma and other lymphoproliferative diseases. Although HHV‐8 prevalence exhibits considerable variation in different geographic regions and populations, the incidence of Kaposi's sarcoma appear to increase in areas with a high prevalence rate. In this study, an enzyme‐linked immunosorbent assay based on mixed antigens of HHV‐8 ORF73, ORF65, and K8.1 in the antigenic region was established and used to determine viral prevalence estimates and risk factors associated with HHV‐8 infection. Of 482 tumor patients studied, the overall seropositivity of HHV‐8 was 25.5%. Notably, Han people, who were immigrants or descendents of immigrants from inland of China, exhibited 26.4% seropositivity. This is similar to that observed in Uygur people, a local ethnic group with a high prevalence of HHV‐8 infection and incidence of Kaposi's sarcoma. While there was no significant difference in patients with different tumors, HHV‐8 seroprevalence was higher in individuals with malignant diseases. Logistic regression analysis suggests that the age is a risk factor associated with HHV‐8 infection, with prevalence increasing from 12.5% under 20–27.5% above 50. These results suggest that unlike other parts of mainland of China, Xinjiang is an area with a high prevalence of HHV‐8 infection. J. Med. Virol. 79:161–166, 2007. © 2006 Wiley‐Liss, Inc.
Chimeric HIV‐1 and HIV‐2 lentiviral vectors with added safety insurance
Authors: Sachdeva Geetanjali , D'Costa Jenice , Cho Jang E. , Kachapati Kritika , Choudhry Vidita , Arya Suresh K. 
Published: December 2006

AbstractLentiviruses are unique in their ability to infect both dividing and non‐dividing cells. This makes the vectors derived from them particularly useful for gene transfer into non‐dividing cells, including stem cells. Lentiviral vectors are becoming the vectors of choice for si/shRNA delivery. The utility of the lentiviral vectors will be enhanced if additional elements of safety are built into their design. One safety concern is the generation of replication competent virus by recombination. We reasoned that HIV‐1 and HIV‐2 hybrid or chimeric lentiviral vectors will have added safety insurance in this regard. This is based on the premise that HIV‐1 and HIV‐2 are dissimilar enough in sequence to curtail recombination, yet similar enough to complement functionally. For hybrid vectors, we found that both HIV‐1 and HIV‐2 transfer vector RNAs could be packaged to equivalent titer by the HIV‐1 packaging machinery. However, HIV‐2 packaging machinery was unable to package HIV‐1 transfer vector as well as it did HIV‐2 transfer vector. This non‐reciprocacity suggested that the requirement for HIV‐2 vectors was more stringent and that for HIV‐1 vectors more promiscuous. When the HIV‐1 transfer vector was packaged with the chimeric packaging construct where the leader‐gag region of HIV‐2 was replaced with that of HIV‐1 packaging construct, the titer of the vector went up. This suggests that at least some of the determinants of specificity for vector assembly reside in the leader‐gag region. Incorporation of central polypurine tract (cPPT) and woodchuck post‐transcriptional enhance element (WPRE) into the HIV‐2 vectors had only modest effect on vector titer. Thus, chimeric lentiviral vectors with added safety features can be designed without compromising transduction efficiency. J. Med. Virol. 79:118–126, 2007. © 2006 Wiley‐Liss, Inc.
Hepatitis C Virus p7 membrane protein quasispecies variability in chronically infected patients treated with interferon and ribavirin, with or without amantadine
Authors: Castelain S. , Bonte D. , Penin F. , François C. , Capron D. , Dedeurwaerder S. , Zawadzki P. , Morel V. , Wychowski C. , Duverlie G. 
Published: December 2006

AbstractA clinical study was carried out to compare the response rate of two groups of non‐responder (NR) hepatitis C virus (HCV) genotype 1 chronically infected patients treated with interferon and ribavirin, with or without amantadine. The viral load decreased more markedly in the group treated by tritherapy including amantadine, but the response rate at the end of treatment was not significantly different between bitherapy and tritherapy. As amantadine could have an antiviral effect on the ion channel activity of the p7 HCV protein, the p7 quasispecies was characterized by cloning and sequencing. Sequence data were analyzed to determine the pattern and significance of p7 genetic heterogeneity and a possible relationship with therapy. Subtype differences were confirmed between p7 HCV genotypes 1a and 1b, and quasispecies analysis showed a reduction of genetic diversity in subtype 1a, but not 1b, during tritherapy. However, the absence of changes at numerous positions, as well as the conservative changes at other positions, indicated the high conservation of the p7 structure. Residue His‐17, proposed to interact with amantadine, was fully conserved in both subtypes 1a and 1b, independently of amantadine administration. In conclusion, although the analysis of the p7 sequences revealed a selective pressure during therapy, no specific residues appeared to be linked to the effect of amantadine on viral decline. These results suggest that the potential antiviral effect of amantadine might be non‐specific and related to a reduction in endosomal acidification and therefore reduced viral entry of HCV via its pH‐dependent pathway. J. Med. Virol. 79:144–154, 2007. © 2006 Wiley‐Liss, Inc.