bluuebunny/crossref_metadata_2025_split huggingface dataset:
Basal replication of hepatitis C virus in nude mice harboring human tumor
Authors: Labonté Patrick , Morin Nicolas , Bowlin Terry , Mounir Samir 
Published: August 2002

AbstractHepatitis C virus (HCV) can infect and propagate in humans and chimpanzees. Whereas the chimpanzee has been used as an animal model for infection, ethical considerations, conservation, and the prohibitively high cost preclude progress for experimental research on the biology of the virus. The development of a small animal model for HCV infection is thus desirable to facilitate studies on the infectious cycle of the virus and for the evaluation of drugs for the treatment of HCV infections in humans. As an alternative to the chimpanzee model, we have established a model based on ex vivo infection of orthotopically‐implanted human hepatocellular carcinoma cells (HCC) in athymic nude mice. The results show that up to 42 days post‐infection, HCV RNA was present in the tumor cells as well as in the liver and serum of infected mice. Furthermore, a direct correlation between size of the tumor and the presence of HCV RNA in the liver was observed, which is concordant with the finding that HCV RNA was detectable only in mice harboring human tumor. Immunohistochemistry analysis of infected liver specimens showed cells expressing the HCV encoded NS5B protein. A few mice developed a humoral response against the nonstructural viral proteins, providing further evidence for expression of these proteins during viral infection. In summary, these results suggest that mice harboring orthotopic tumors support a basal level of HCV replication in vivo. J. Med. Virol. 66:312‐319, 2002. © 2002 Wiley‐Liss, Inc.
Co‐delivery of GM‐CSF gene enhances the immune responses of hepatitis C viral core protein‐expressing DNA vaccine: Role of dendritic cells
Authors: Ou‐Yang Pu , Hwang Lih‐Hwa , Tao Mi‐Hua , Chiang Bor‐Luen , Chen Ding‐Shinn 
Published: August 2002

AbstractHepatitis C virus (HCV) infection has become a critical public health problem worldwide. In Taiwan, it has been estimated that more than 300,000 people, 2% of the general population, have HCV infection. It has been well documented that direct delivery of gene intramuscularly can generate both humoral and cellular immunity, which more closely simulates the conditions of infection. In this study, female Balb/c mice immunized with HCV core plasmid DNA with or without adjuvant GM‐CSF cytokine gene could induce both cellular immune response and HCV core‐specific antibody titers after injection. Furthermore, the mice immunized with HCV core plus GM‐CSF genes showed higher antibody titer and cytotoxic T cell activity compared to those of mice immunized with HCV core gene only (P < 0.05). To explore the effect of GM‐CSF gene, the mice were immunized with reporter gene and cytokine gene plasmid. Increased levels of reporter protein and infiltrating cells around muscle tissue were noted. Moreover, the protein could be detected in inguinal node 24 hr after injection, especially in mice immunized with HCV/core plasmid plus GM‐CSF gene. It was also observed that reporter protein expressing CD11c+ dendritic cells could be seen in the inguinal node. These data suggest that the GM‐CSF gene did enhance HCV core specific immune response when co‐immunized with HCV core DNA plasmid. Although more studies are needed, dendritic cells that appeared around the naked DNA injection area and that local lymph nodes might play a critical role in the immune response induced by naked DNA immunization. J. Med. Virol. 66:320‐328, 2002. © 2002 Wiley‐Liss, Inc.
GABAB receptor gene expression is not altered in cocaine‐sensitized rats
Authors: Li Jinyuan , Olinger Anthony B. , Dassow Michael S. , Abel Marc S. 
Published: August 2002

AbstractRecent behavioral and neurobiological data indicate that GABAB receptor transmission is involved in cocaine‐induced hyperactivity and reinforcement. GABAB receptor gene expression in cocaine‐sensitized rats was examined in this study. Rats were injected with cocaine (15 mg/kg, daily, i.p.) or saline for 5 consecutive days, and challenged with the same dose of cocaine after a 1‐, or 20‐day hiatus. The locomotor activities of rats were recorded after challenge, and the rats were killed 24 hr later. GABABR1a, 1b, and GABABR2 mRNA in discrete brain regions was detected by RPA and In Situ Hybridization; GABABR1a protein was measured by Western blotting. Rats pretreated with cocaine developed a hyperactivity to the cocaine challenge after a 1‐day or 20‐day hiatus, but GABABR subunit mRNA and GABABR1a protein densities in the targeted regions showed no significant difference compared to those in control rats. These data indicate that GABAB receptor gene expression is not necessarily relevant to the behavioral sensitization of cocaine. © 2002 Wiley‐Liss, Inc.
Effect of exogenous lactate on rat glioma metabolism
Authors: Bouzier‐Sore Anne‐Karine , Canioni Paul , Merle Michel 
Published: August 2002

AbstractGlioma‐bearing rats were infused intravenously with a solution containing either [3‐13C]lactate or both glucose and [3‐13C]lactate for 20 min or 1 hr. Perchloric acid extracts of healthy and tumoral brain tissues were prepared and analyzed by 13C‐ and 1H‐observed 13C‐edited nuclear magnetic resonance (NMR) spectroscopy to determine 13C‐label incorporation into brain tissue and glioma metabolites. Moreover, 13C enrichments in blood lactate and glucose were determined from 1H‐NMR spectra. In the nontumoral tissue, 13C labeling of amino acids indicated that [3‐13C]lactate entered the brain and was metabolized. There was no labeling difference between the contralateral and the ipsilateral hemispheres. Lactate metabolism appeared more specifically neuronal, in agreement with our previous results obtained with normal rat brain (Bouzier et al. [2000] J. Neurochem. 75:480–486). In the glioma tissue, comparison of Ala C3, Glu C4, and Gln C4 labeling indicated that the contributions of blood glutamine and tricarboxylic acid (TCA) cycle to glutamate labeling were about 80% and 20%, respectively, after 1 hr of [3‐13C]lactate infusion. In contrast, these contributions were about 10% and 90%, respectively, when [1‐13C]glucose was infused in the absence of lactate. This indicated a major effect of the exogenous lactate on glioma metabolism, which may be due to the following process: The high blood lactate level might hinder the drain of glycolytic lactate produced inside the glioma and thus generate a change in redox potential such that the tumor cells are unable to restore it with oxidative phosphorylation. Thereafter, the high NADH level might inhibit glycolysis and the TCA cycle, and glutamine could become the major carbon source for glutamate labeling. J. Neurosci. Res. 65:543–548, 2001. © 2001 Wiley‐Liss, Inc.
Validation of ECMWF (re)analysis surface climate data, 1979–1998, for Greenland and implications for mass balance modelling of the ice sheet
Authors: Hanna Edward , Valdes Paul 
Published: August 2002

AbstractClimate (re)analysis products are potentially valuable tools, when properly verified, for helping to constrain the surface mass balance of the Greenland Ice Sheet (GIS). Monthly surface fields from European Centre for Medium‐Range Weather Forecasts (ECMWF) operational‐ and re‐analyses spanning 1979–1998 were validated using in situ data (surface air pressure and temperature, precipitation, cloud cover, short‐/all‐wave radiation, and wind speed/direction). These validation data are from coastal or near‐coastal Danish Meteorological Institute (DMI) synoptic stations, inland Greenland Climate Network (GC‐Net) and University of Wisconsin Automatic Weather Stations (AWSs), and two energy balance stations near the southern ice margin. The ECMWF analyses closely reproduce the seasonal patterns and interannual variations of much of the in situ data. Differences in the mean values of surface air pressure and temperature can mainly be ascribed to orography errors in the analyses' schemes, compared with the latest available accurate digital elevation model. Much of the GIS margin as modelled by ECMWF was too cold, on average by 4°C, and ECMWF precipitation averaged some 136% of the DMI station values. The misrepresentation of the (relatively) steep ice‐sheet margin, which tends to be broadened and systematically over‐elevated by several hundred metres, orographically reduced temperature and enhanced precipitation there in the ECMWF models. The cloud‐cover comparison revealed not dissimilar annual mean cloud covers (ECMWF −8%) but the ECMWF analyses had too little cloud and were too ‘sunny’ during the critical summer melt‐season. ECMWF‐modelled surface albedo in summer was ∼11% lower than GC‐Net values, which was mainly responsible for the disagreement of modelled surface short‐wave radiation fluxes with observations. Model albedo and cloud errors need to be rectified if the analyses are to be used effectively to drive energy balance models of Greenland snowmelt. ECMWF wind speed averaged 66% (62%) of the DMI station (AWS) values. The validation results provide useful insights into how one can best improve the ECMWF Greenland climate data for use in glaciological and climatological studies. Copyright © 2001 Royal Meteorological Society
Lattice dynamic investigation of Raman and infrared wavenumbers at the zone center of orthorhombic RFeO3 (R = Tb, Dy, Ho, Er, Tm) perovskites
Authors: Gupta H. C. , Kumar Singh Manoj , Tiwari L. M. 
Published: August 2002

AbstractA short‐range force constant model was applied for the first time to investigate the phonons in RFeO3 (R = Tb, Dy, Ho, Er, Tm) perovskites in the orthorhombic phase. The calculations with the 12 stretching and three bending force constants provide good agreement for the observed Raman and infrared wavenumbers. The infrared wavenumbers were assigned for the first time. The variation of the force constants on going from Tb to Tm is discussed . The effect of changing the R ion from Tb to Tm in the Raman modes of RFeO3 is also discussed. Copyright © 2002 John Wiley & Sons, Ltd.
Precision nutrition: weighing feed ingredients correctly
Authors: van Kempen Theo , Park Bill , Hannon Mike , Matzat Paul 
Published: August 2002

AbstractThe ability to mix a quality feed is often equated to the quality of the mixer; the ability to weigh ingredients correctly has received little attention. To assess how accurately feed mills weigh their ingredients, 14 feed mills specialising in swine diets were surveyed, which yielded 8432 data points (for 229 ingredients and 11–44 batch records per ingredient within mills). Amounts actually weighed (according to scale readings) were compared to calls, and differences were analysed statistically. Feed mills overdosed ingredients by 1.5 ± 16.3%: between mills, overdosing ranged from −0.7 to 13.0%. Within ingredients, weighing variation ranged from 0.6 to 11.1% between mills and averaged 5.2%. Some of the weighing problems observed were attributed to discrepancies between the call size and the scale resolution. For example, weighing 11.3 units (pounds) on a scale with a 2 unit resolution leads to a minimum error of 6%. Such problems occurred for 8.7% of the calls and resulted in a minimum error ranging from 0.01 to 20%, averaging 1.95%. Poor choice of scales was the major source of errors in weighing, and the relationship weighing variation = 10∧ [1.56 − 0.50 log (call/scale resolution)] explained 40% of the variation observed (p < 0.05). Weighing ingredients in the right scale would thus not only benefit feed quality but also reduce diet cost, as it would reduce the overdosing of ingredients.© 2001 Society of Chemical Industry
Cell death in the colorectal cancer cell line HT29 in response to glucosinolate metabolites
Authors: Lund Elizabeth K , Smith Tracy K , Clarke Rosemary G , Johnson Ian T 
Published: August 2002

AbstractGlucosinolate breakdown products are potential anti‐carcinogenic phytochemicals derived from cruciferous vegetables. This study compared the induction of apoptosis in colorectal adenocarcinoma cells (HT29) by four isothiocyanates (ITC) benzyl‐ITC, allyl‐ITC (AITC), phenylethyl‐ITC (PEITC) and methylsulphinylbutyl‐ITC (sulforaphane). Apoptosis was determined by analysis of DNA content, annexin V staining, gel electrophoresis, CPP32 expression/inhibition and the histological appearance of nuclei. In terms of their ability to reduce adherent cell number, the relative potency of ITCs was BITC = AITC > PEITC ≫ sulforaphane. Non‐adherent cells from test flasks showed less evidence of apoptosis than those grown under control conditions. Our results implied that ITCs first blocked cells at G2/M and subsequently caused a loss in adherence which was not reduced by caspase inhibitors or by pre‐loading the cells with an antioxidant, the GST mimic Ebselen. This suggests that the primary action of ITCs is to block rapidly proliferating cancer cells in G2/M. In this particular p53 null cell line, loss of cell adherence was not part of an apoptotic process, nor did it involve free radical signaling pathways.© 2001 Society of Chemical Industry.
Some studies directed at increasing the potential use of palmyrah (Borassus flabellifer L) fruit pulp
Authors: Ariyasena Darshika D , Jansz E R , Abeysekera A M 
Published: August 2002

AbstractAttempts have been made to predict the most feasible end‐use for palmyrah fruit pulp (PFP), which is still largely regarded as a waste product. Correlation of end‐use with flabelliferin profile is logical but practically difficult, as it has been found that the morphology of the fruit and the colour of the pulp (carotenoid content) do not correlate with each other, and that neither has predictive value for the flabelliferin profile. It appears that some varieties of palmyrah are sweet and can be used for products such as jams and cordials. A few very bitter PFPs can be de‐bittered with a cheap commercial enzyme for similar uses. The majority of available PFP appears to be best used as an alcoholic fermentation base, with the possibility of using the carotenoids (by‐product) as a food colorant.© 2001 Society of Chemical Industry
Mutations in the von Hippel‐Lindau (VHL) gene refine differential diagnostic criteria in renal cell carcinoma
Authors: Barnabas Nandita , Amin Mitual B. , Pindolia Kirit , Nanavati Reshma , Amin Mahul B. , Worsham Maria J. 
Published: August 2002

AbstractBackground and ObjectivesRenal cell carcinomas (RCC) with abundant granular cytoplasm include oncocytomas, eosinophillic variants of chromophobe RCC, papillary RCC, collecting duct carcinoma, and some conventional (clear cell) RCC. Tumors with predominantly clear cell cytoplasm include typical chromophobe RCC and conventional (clear cell) RCC. The objective of this study was to determine if mutations in the VHL gene can serve as auxiliary diagnostic criteria in refining histology based subtyping of renal epithelial neoplasia.MethodsThe study cohort of 67 cases included 24 conventional RCC, 14 chromophobe RCC, 14 papillary RCC, and 15 oncocytomas. Single strand conformational polymorphism (SSCP) was used as a screening procedure for mutations followed by automated sequencing to identify mutations.ResultsThirteen of the 14 mutations identified were novel, seven of which were in the coding region. In chromophobe RCC, mutations clustered in the 5′UTR/promoter region and have not been previously reported. Exon 3 appeared to favor conventional (clear cell) RCC and correlated with a more aggressive phenotype. Mutations were absent in the papillary and oncocytoma RCC subtypes.ConclusionsExon 3 mutations permitted a morphological distinction between conventional (clear cell) RCC and chromophobe RCC with clear cells. Mutations in the VHL gene refine histologic diagnostic criteria in RCC serving as adjuncts to the present morphology based diagnosis of RCC. J. Surg. Oncol. 2002;80:52–60. © 2002 Wiley‐Liss, Inc.
Multinational hotel development in developing countries: an exploratory analysis of critical policy issues
Authors: Kusluvan Salih , Karamustafa Kurtulus 
Published: August 2002

AbstractMultinational hotel companies, often integrated with tour operators, travel agencies and other businesses in tourist‐generating or tourist‐receiving countries, play a key role in the development and continuity of an international tourism industry in developing countries. In order to take advantage of benefits and minimise the unwanted adverse effects from multinational hotel involvement, developing countries need the planning, implementation and evaluation of carefully designed policies linked to their particular objectives. This paper reviews the potential benefits and costs of multinational hotel companies and brings together previously scattered critical policy issues in relation to them, while suggesting possible options for developing countries to follow. Seven critical policy areas are identified: establishment of the need for foreign investment; deciding on forms of involvement; deciding on the scale of hotel development; supporting sectoral linkages; supporting indigenous employment/training; monitoring business practices; and determining foreign investment incentives and regulations. It is argued that policies should be worked out in these areas and co‐ordinated in order to achieve a balance between the benefits and costs of multinational hotel involvement in developing countries. Copyright © 2001 John Wiley & Sons, Ltd.
Uncivil aviation: a review of the air rage phenomenon
Authors: Morgan Michelle , Nickson Dennis 
Published: August 2002

AbstractThis article examines the issue of air rage. Attempting to define and identify the extent of this phenomenon provides the context in which to review contributory factors. The analysis of violence or aggression directed at flight attendants is developed with recourse to the work of Poyner and Warne, who offer a framework for understanding violence to staff. Use of this framework suggests that air rage remains a multifaceted phenomenon, with a number of contributory factors. Identification of a variety of factors is then used to develop an analysis of possible solutions to the air rage phenomenon. These solutions are concerned with controlling the assailant and, more proactively, supporting flight attendants through initiatives such as enhanced training programmes. Finally, the article suggests a number of areas for future research that may add to an understanding of a so‐far under investigated phenomenon. Copyright © 2001 John Wiley & Sons, Ltd.
Reaction of 4‐benzylidene‐2‐methyl‐5‐oxazolone with amines, Part 2: Influence of substituents in para‐position in the phenyl ring and a substituent on amine nitrogen atom on the reaction kinetics
Authors: Betłakowska B. , Banecki B. , Czaplewski C. , Łankiewicz L. , Wiczk W. 
Published: August 2002

AbstractAn influence of a structure of the amine (benzylamine, N‐methyl‐benzylamine, N‐isopropyl‐benzylamine, N‐methyl‐butylamine, N‐ethyl‐butylamine, sec‐butylamine, and tert‐butylamine) on a rate constant of the ring‐opening reaction of 4‐benzylidene‐2‐methyl‐5‐oxazolone (Ox) was studied. The good correlation between logarithm of the rate constants and Charton's steric substituent constant ν as well as good correlation with a form of the simple branching equation indicate that there is a steric effect because of substitution at C1 carbon atom of nucleophile which decreases the reaction rate. Additionally, an influence of a structure of the benzylidene moiety of Ox on a rate of the oxazolone ring‐opening reaction was studied. The substituents (OH, OCH3, N(CH3)2, Cl, NO2) in para‐position of the phenyl ring of Ox substantially modified the rate of the reaction with benzylamine in acetonitrile. The rate of the Ox ring‐opening reaction decreased with increase of the electron‐donating properties of the substituent. A good correlation between the rate constants of the reaction of 4‐(4′‐substituted‐benzylidene)‐2‐methyl‐5‐oxazolones with benzylamine and the electron density at the reaction center (carbon C5 of the oxazolone ring), calculated using ab initio method, and the Hammett substituent constants, and CR equation were established. © 2002 Wiley Periodicals, Inc. Int J Chem Kinet 34: 148–155, 2002; DOI 10.1002/kin.10039
Heterogeneous kinetic studies of the hydrogen peroxide decomposition with some transition metal‐heterocyclic complexes
Authors: El‐Safty S. A. , El‐Sheikh M. Y. , Salem M. A. , Zaki A. B. 
Published: August 2002

AbstractThe heterocyclic compounds piperidine (Pip), piperazine (Pz), morpholine (Morph), and N‐methyl piperazine (N‐MPz) were used as ligands to form transition metal complexes with Ni(II), Cu(II), and Co(II) ions. These complexes were supported on Dowex‐50W resin so as to form new potential active catalysts for H2O2 decomposition in an aqueous medium. In all cases the reaction showed a first‐order kinetics with respect to H2O2 concentration, except with Co(II) complexes, the reaction showed a second‐order kinetics with 2% divinyl benzene (DVB) (50–100 mesh and 200–400 mesh). The rate constant k (per gram dry resin) was evaluated with a resin of cross‐linkage 2 and 8% DVB (50–100 mesh) and 2% DVB (200–400 mesh) over temperature range 25–40°C. With a given resin cross‐linkage, the rate constant has the following order: Ni(II) complexes < Co(II) complexes < Cu(II) complexes. With Pz ligand, k increased in the following sequence: Ni(II) complexes < Cu(II) complexes < Co(II) complexes. The reaction mechanisms of the first‐ and second‐order kinetics were discussed and the activation parameters were deduced. © 2001 John Wiley & Sons, Inc. Int J Chem Kinet 33: 617–624, 2001
Oilseed rape and field bean production potential on an amended former landfill site restored with London clay
Authors: Sellers G. , McRae S. G. , Cook H. F. 
Published: August 2002

AbstractRe‐establishment of vegetation on landfill sites, as required in UK planning consents, frequently means establishing viable arable agriculture rather than grassland. However, there is currently little information on crop suitability or yield, especially where the land has been restored with clay subsoils.Results are presented from three years growing oilseed rape and two years growing field beans, on a landfill site in south Essex, England, which was restored with London Clay. The site was restored in two ways. One area had a 900 mm depth of London Clay applied on top of the capped landfill. The second area had a 700 mm depth of London Clay topped with 200 mm of imported sieved material (known as screened material or ‘screenings’) which looked suitable for use as a soil forming substrate. The amendments tested were indigenous topsoil, screened material, mineral fertilizer, greenwaste compost or sewage sludge cake.Results show that oilseed rape is not suitable. It performed poorly regardless of amendment (greatest yield = 1.1 t ha−1 or 50 per cent of average agricultural yield). Mineral fertilizer produced some small improvement with oilseed rape when grown on London Clay or with a topsoil‐forming layer of screenings. Beans performed well (greatest yield 3.9 t ha−1, comparable to average agricultural yields). Sludge cake had little effect on bean growth performance and both crops performed poorly on land amended with green waste compost. Screenings improved yield if sludge or no amendment was used, but had no effect when mineral fertilizer was applied. Copyright © 2001 John Wiley & Sons, Ltd.