bluuebunny/crossref_metadata_2025_split huggingface dataset:
A kinematic‐wave‐based distributed watershed model using FEM, GIS and remotely sensed data
Authors: Venkata Reddy K. , Eldho T. I. , Rao E. P. , Hengade N. 
Published: January 2007

AbstractFor the appropriate management of water resources in a watershed, it is essential to calculate the time distribution of runoff for the given rainfall event. In this paper, a kinematic‐wave‐based distributed watershed model using finite element method (FEM), geographical information systems (GIS) and remote‐sensing‐based approach is presented for the runoff simulation of small watersheds. The kinematic wave equations are solved using FEM for overland and channel flow to generate runoff at the outlet of the watershed concerned. The interception loss is calculated by an empirical model based on leaf area index (LAI). The Green‐Ampt Mein Larson (GAML) model is used for the estimation of infiltration. Remotely sensed data has been used to extract land use (LU)/land cover (LC). GIS have been used to prepare finite element grid and input files such as Manning's roughness and slope. The developed overland flow model has been checked with an analytical solution for a hypothetical watershed. The model has been applied to a gauged watershed and an ungauged watershed. From the results, it is seen that the model is able to simulate the hydrographs reasonably well. A sensitivity analysis of the model is carried out with the calibrated infiltration parameters, overland flow Manning's roughness, channel flow Manning's roughness, time step and grid size. The present model is useful in predicting the hydrograph in small, ungauged watersheds. Copyright © 2007 John Wiley & Sons, Ltd.
Human retinoblastoma is not caused by known pRb‐inactivating human DNA tumor viruses
Authors: Gillison Maura L. , Chen Renwei , Goshu Eleni , Rushlow Diane , Chen Ning , Banister Carolyn , Creek Kim E. , Gallie Brenda L. 
Published: January 2007

AbstractRetinoblastomas occur as the consequence of inactivation of the tumor suppressor retinoblastoma protein (pRb), classically upon biallelic inactivation of the RB1 gene locus. Recently, human papillomavirus (HPV) genomic DNA has been detected in retinoblastomas. To investigate the possibility that oncoproteins encoded by pRb‐inactivating DNA tumor viruses play a role in the pathogenesis of human retinoblastoma, 40 fresh‐frozen tumors were analyzed for the presence of HPV, adenovirus (HAdV) and polyomavirus (BKV, JCV and SV40) genomic DNA sequences by real‐time polymerase chain reaction (PCR). Tumors were screened for genetic and epigenetic alterations in all 27 exons of the RB1 gene locus and promoter by exonic copy number detection, sequencing and methylation‐specific PCR of the promoter region. Retinoblastoma tumors from children with bilateral familial (n = 1), bilateral nonfamilial (n = 1) and unilateral nonfamilial (n = 38) disease were analyzed. Inactivating modifications to the RB1 gene locus were identified on both the alleles in 27 tumors, one allele in 8, and neither allele in 5 cases. A median of over 107,000 tumor cells were analyzed for viral genomic DNA in each PCR reaction. All tumor samples were negative for 37 HPV types, 51 HAdV types, BKV and JCV genomic sequences. Very low copy number (0.2–260 copies per 100,000 tumor cells) SV40 genomic DNA detected in 8 of 39 samples was demonstrated to be consistent with an artifact of plasmid‐derived SV40. In contrast to recent reports, we obtained substantial quantitative evidence indicating that neither HPV nor any other pRb‐inactivating human DNA tumor viruses play a role in the development of retinoblastoma, regardless of RB1 genotype. © 2006 Wiley‐Liss, Inc.
Opposite effects of high glucose on MMP‐2 and TIMP‐2 in human endothelial cells
Authors: Ho Feng M. , Liu Shing H. , Lin Wan W. , Liau Chiau S. 
Published: January 2007

AbstractDiabetes mellitus (DM) is a major risk factor for atherosclerosis and causes multiple cardiovascular complications. Although high glucose can induce matrix metalloproteinases (MMPs), its inhibitors and cell apoptosis, little is known about the roles of MMPs in regulating cell apoptosis in response to high glucose. To address this issue, we elucidated the relationship between MMPs, its inhibitors and cell apoptosis in human umbilical vein endothelial cells (HUVECs). HUVECs were treated with medium containing 5.5 mM or 33 mM of glucose in the presence or the absence of ascorbic acid and MMP inhibitors (GM6001 and endogenous tissue inhibitors of MMPs, TIMP‐1, and TIMP‐2). For detection of cell apoptosis, the cell death detection ELISA assay was used. The results revealed that high glucose‐induced apoptosis could be suppressed by ascorbic acid, GM6001 and TIMP‐2, but not by TIMP‐1. The activities of MMP‐2, MMP‐9 and its inhibitors, TIMP‐1, TIMP‐2 after high glucose treatment, were also detected by ELISA method. We found that the activated form of MMP‐2, but not MMP‐9, was increased, while the level of TIMP‐2, but not TIMP‐1, was decreased. In Western blot and RT‐PCR analysis, the expression of TIMP‐2, but not TIMP‐1, after high glucose treatment was downregulated, whereas the levels of MMP‐2 and ‐9 proteins and mRNA were not changed. The present study indicated that oxidative stress induced by high glucose might be involved in the opposite effects on MMP‐2 activation and TIMP‐2 downregulation. This reactive oxygen species (ROS)‐dependent MMP‐2 activation in turn mediates high glucose‐induced cell apoptosis in HUVECs. J. Cell. Biochem. 101: 442–450, 2007. © 2007 Wiley‐Liss, Inc.
Poly(ϵ‐caprolactone)‐b‐poly(ethylene glycol)‐b‐poly(ϵ‐caprolactone) triblock copolymers: Synthesis and self‐assembly in aqueous solutions
Authors: Zhang Yaqiong , Guo Shengrong , Lu Chengfei , Liu Li , Li Zonghai , Gu Jianren 
Published: January 2007

AbstractNontoxic and biodegradable poly(ϵ‐caprolactone)‐b‐poly(ethylene glycol)‐b‐poly(ϵ‐caprolactone) triblock copolymers were synthesized by the solution polymerization of ϵ‐caprolactone in the presence of poly(ethylene glycol). The chemical structure of the resulting triblock copolymer was characterized with 1H NMR and gel permeation chromatography. In aqueous solutions of the triblock copolymers, the micellization and sol–gel‐transition behaviors were investigated. The experimental results showed that the unimer‐to‐micelle transition did occur. In a sol–gel‐transition phase diagram obtained by the vial‐tilting method, the boundary curve shifted to the left, and the gel regions expanded with the increasing molecular weight of the poly(ϵ‐caprolactone) block. In addition, the hydrodynamic diameters of the micelles were almost independent of the investigated temperature (25–55 °C). The atomic force microscopy results showed that spherical micelles formed at the copolymer concentration of 2.5 × 10−4 g/mL, whereas necklace‐like and worm‐like shapes were adopted when the concentration was 0.25 g/mL, which was high enough to form a gel. © 2006 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 45: 605–613, 2007
Effects of diets enriched in eicosapentaenoic or docosahexaenoic acids on prostanoid metabolism in the rat
Authors: Croft Kevin D. , Beilin Lawrence J. , Legge Frank M. , Vandongen Robert 
Published: January 2007

AbstractTo clarify the effects of eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) on prostaglandin biosynthesis, diets supplemented with oils rich in one fatty acid or the other were fed to rats over a 4‐wk period. Animals fed the Max EPA diet showed a significant decrease in plasma and tissue phospholipid arachidonic acid content. While plasma levels of DHA increased on a shark liver oil diet enriched in DHA, the liver and kidney phospholipid contents of DHA were not altered. In addiition, the DHA‐enriched diet did not decrease the arachidonic acid content of either liver or kidney phospholipids. Whole blood thromboxane and vascular prostacyclin synthesis were decreased by 65% and 36%, respectively, in animals fed the Max EPA diet. No such decrease was seen in the rats fed DHA‐enriched diets. We conclude from these results that in the rat DHA is not likely to have a significant effect on prostaglandin synthesis when given as a dietary supplement.
Perfluoro‐n‐decanoic acid: Induction of peroxisomal β‐oxidation by a fatty acid with dioxin‐like toxicity
Authors: Harrison Earl H. , Lane J. Scott , Luking Scott , Van Rafelghem Marc J. , Andersen Melvin E. 
Published: January 2007

AbstractPerfluoro‐n‐decanoic acid (PFDA) produces toxic effects in rodents similar to those caused by 2,3,7,8‐tetrachlorodibenzo‐p‐dioxin. A single, intraperitoneal dose (50 mg/kg) of PFDA to Sprague‐Dawley rats caused disruption of the endoplasmic reticulum, mitochondrial swelling and increases in intracellular lipid droplets in hepatocytes similar to effects reported previously in dioxin toxicity. PFDA treatment led to large decreases in the activity of plasma membrane alkaline phosphodiesterase and mitochondrial cytochrome c oxidase without affecting lysosomal N‐acetyl‐β‐glucoaminidase, endoplasmic reticulum NADPH‐cytochrome c reductase or peroxisomal catalase activities. PFDA treatment led to moderate peroxisome proliferation and to very large (20–40‐fold) increases in the activity of fatty acyl‐CoA oxidase, the rate‐limiting enzyme in the peroxisomal system of fatty acid β‐oxidation.
Biosynthesis of molecular species of CDP‐diglyceride from endogenously‐labeled phosphatidate in rat liver microsomes
Authors: Holub B. J. , Piekarski J. 
Published: January 2007

AbstractThe biosynthesis of [14C] CDP‐diglyceride was studied using rat liver microsomes which were endogenously labeled with [14C] phosphatidic acid by preincubation of unlabeled microsomes withsn‐[14C]glycerol‐3‐phosphate and appropriate cofactors. The formation of CDP‐diglyceride from radioactive phosphatidate showed an absolute requirement for CTP and MgC12. The newly formed [14C] CDP‐diglyceride was characterized by thin layer chromatography (TLC), isotopic labeling from radioactive CTP, and its ability to serve as substrate for the microsomal enzyme, CDP‐diglyceride: inositol phosphatidyltransferase. The distributions of radioactive glycerol‐3‐phosphate among the various chemical classes of microsomal [14C] phosphatidate and [14C]CDP‐diglyceride were determined following argentation TLC of their 1,2‐diglyceride acetate derivatives. Most of the radioactivity among the phosphatidic acids was present in the monoenoic (36%) and dienoic (33%) molecular species, whereas 10, 8, 4, and 8% were associated with the saturates, trienes, tetraenes, and polyenes, respectively. Similar distributions of radioactivity were found among the corresponding classes of newly formed CDP‐diglyceride. Only a slight enrichment of radioactivity in the tetraenoic CDP‐diglyceride was found relative to the corresponding phosphatidates. Therefore, under the conditions of study, the microsomal CTP:phosphatidate cytidylyltransferase produces mainly monoenoic and dienoic species of CDP‐diglyceride and shows little specificity towards different molecular species of phosphatidic acids. The present results suggest also that the arachidonoyl phosphatidate derived from the microsomal acylation ofsn‐glycerol‐3‐phosphate is not likely the major source of arachidonic acid in liver phosphatidylinositol.
Kinetic study of the reaction between tocopheroxyl radical and unsaturated fatty acid esters in benzene
Authors: Mukai Kazuo , Okauchi Yuji 
Published: January 2007

AbstractA kinetic study of the reaction between a tocopheroxyl radical and unsaturated fatty acid esters has been undertaken. The rates of allylic hydrogen abstraction from various unsaturated fatty acid esters (ethyl oleate2, ethyl linoleate3, ethyl linolenate4, and ethyl arachidonate5) by the tocopheroxyl radical (5,7‐diisopropyltocopheroxyl6) in benzene have been determined spectrophotometrically. The second‐order rate constants, k3, obtained are 1.04×10−5 M−1s−1 for2, 1.82×10−2 M−1s−1 for3, 3.84×10−2 M−1s−1 for4, and 4.83×10−2 M−1s−1 for5 at 25.0°C. Thus, the rate constants, kabstr/H, given on an available hydrogen basis are k3/4=2.60×10−6 M−1s−1 for2, k3/2=9.10×10−3 M−1s−1 for3, k3/4=9.60×10−3 M−1s−1 for4, and k3/6=8.05×10−3 M−1s−1 for5. The kabstr/H values obtained for the polyunsaturated fatty acid esters3,4, and5 containing H‐atoms activated by two π‐electron systems are similar to each other, and are about three orders of magnitude higher than that for the ethyl oleate2 containing H‐atoms activated by a single π‐system. From these results, it is suggested that the prooxidant effect of α‐tocopherol in edible oils and fats may be induced by the above hydrogen abstraction reaction.
Proline reduces brain cytochrome c oxidase: prevention by antioxidants
Authors: Delwing Daniela , Delwing Débora , Chiarani Fábria , Kurek Andréa G. , Wyse Angela T.S. 
Published: January 2007

AbstractIn the present study, we initially investigated the in vivo (acute and chronic) and in vitro effects of proline on cytochrome c oxidase (complex IV) activity in rat cerebral cortex to test the hypothesis that proline might alter energy metabolism and that this alteration could be provoked by oxidative stress. The action of α‐tocopherol and ascorbic acid on the effects produced by proline was also evaluated. For acute administration, 29‐ and 60‐day‐old rats received one subcutaneous injection of proline (18.2 μmol/g body weight) or an equivalent volume of 0.9% saline solution (control) and were sacrificed 1 h later. For chronic treatment, proline was injected subcutaneously twice a day at 10 h intervals from the 6th to the 28th day of age. Rats were sacrificed 12 h (29th) or 31 days (60th) after the last injection. Results showed that acute administration of proline significantly diminished the activity of cytochrome c oxidase in the cerebral cortex of 29‐ and 60‐day‐old rats. On the other hand, chronic hyperprolinemia reduced this complex activity only on day 29, but not on the 60th day of life. In another set of experiments, 22‐day‐old rats or 53‐day‐old rats were pretreated for 1 week with daily intraperitoneal administration of α‐tocopherol (40 mg/kg) and ascorbic acid (100 mg/kg) or saline. Twelve hours after the last antioxidant injection, rats received a single injection of proline or saline and were killed 1 h later. In parallel to chronic treatment, rats received a daily intraperitoneal injection of α‐tocopherol and ascorbic acid from the 6th to the 28th day of life and were killed 12 h after the last injection. Results showed that the pretreatment with α‐tocopherol and ascorbic acid before acute proline administration or concomitant to chronic proline administration significantly prevented these effects. We also observed that proline (3.0 μM–1.0 mM) when added to the incubation medium (in vitro studies) did not alter cytochrome c oxidase activity. Data suggest that the inhibitory effect of proline on cytochrome c oxidase activity is possibly associated with oxidative stress and that this parameter may be involved in the brain dysfunction observed in hyperprolinemia.
Validation of Surgical Site Infection Surveillance in The Netherlands
Authors: Manniën J. , van der Zeeuw A. E. , Wille J. C. , van den Hof S. 
Published: January 2007

Objectives.To describe how continuous validation of data on surgical site infection (SSI) is being performed in the Dutch National Nosocomial Infection Surveillance System (Preventie Ziekenhuisinfecties door Surveillance [PREZIES]), to assess the quality and accuracy of the PREZIES data, and to present the corresponding outcomes of the assessment.Design.Mandatory, 1-day on-site validation visit to participating hospitals every 3 years. The process of surveillance, including the quality of the method of data collection, is validated by means of a structured interview. The use of SSI criteria is validated by review of medical records, with the judgment of the validation team as the criterion standard.Setting.Hospitals participating in PREZIES.Results.During 1999-2004, the validation team visited 40 hospitals and reviewed 859 medical charts. There was no deviation between reports of SSI by infection control professionals and findings by the PREZIES validation team at 30 hospitals and 1 deviation in each of 10 hospitals; the positive predictive value was 0.97, and the negative predictive value was 0.99. The validation team often gave advice to the hospital, aimed at perfecting the process of surveillance. On 2 occasions, data were removed from the PREZIES database after the validation visit revealed deviations from the SSI surveillance protocol that could have resulted in nonrepresentative SSI rate data.Conclusions.PREZIES is confident that the assembled Dutch SSI surveillance data are reliable and robust and are sufficiently accurate to be used as a reference for interhospital comparison. PREZIES will continue performing on-site validation visits, to improve the process of surveillance and ensure the reliability of the surveillance data.
Introducing Alcohol-Based Hand Rub for Hand Hygiene The Critical Need for Training
Authors: Widmer Andreas F. , Conzelmann Martin , Tomic Milanka , Frei Reno , Stranden Anne M. 
Published: January 2007

Background.Use of an alcohol-based hand rub for hand hygiene has recently been recommended by the Centers for Disease Control and Prevention. However, the proper technique for using hand rub has not been well described and is not routinely taught in hospitals.Objective.To evaluate the impact of training on proper technique as outlined by the European Standard for testing alcohol-based hand rubs (European Norm 1500) in a clinical study.Design, Setting, and Patients.Prospective study including 180 healthcare workers (HCWs) in a 450-bed, university-affiliated geriatric hospital where alcohol-based hand rub was introduced in the late 1970s.Intervention.Structured training program in hand hygiene with alcohol-based hand rub. Technique for using hand rub was tested by the addition of a fluorescent dye to the disinfectant and the number of areas missed was quantified by a validated visual assessment method. In addition, the number of bacteria eradicated was estimated by calculating the difference between the log10 number of colony-forming units (cfu) of bacteria on the fingertips before and after the procedure, and reported as reduction factor (RF).Main Outcome Measure.Log10 cfu bacterial counts on fingertips before and after training in the appropriate technique for using hand rub.Results.At baseline, only 31% of HCWs used proper technique, yielding a low RF of 1.4 log10 cfu bacterial count. Training improved HCW compliance to 74% and increased the RF to 2.2 log10 cfu bacterial count, an increase of almost 50% (P < .001). Several factors, such as applying the proper amount of hand rub, were significantly associated with the increased RF.Conclusion.These results demonstrate that education on the proper technique for using hand rub, as outlined in EN 1500, can significantly increase the degree of bacterial killing.
Inhibition by pentachlorophenol of the initiating and promoting activities of 1′-hydroxysafrole for the formation of enzyme-altered foci and tumors in rat liver
Authors: Boberg Eric W. , Liem Amy , Miller Elizabeth C. , Miller James A. 
Published: January 2007

Abstract
The hepatocarcinogen 1′-hydroxysafrole (HOS) exhibited weak initiating activity and strong promoting activity for the induction of enzyme-altered foci and tumors in rat liver. Thus, administration of a single dose of HOS to rats 18 h after a 70% hepatectomy, followed by administration of phenobar-bital (PB) in the diet for 6 months, induced a low, but statistically significant, number of foci of enzyme-altered cells. This treatment did not result in gross liver tumors, even when the PB treatment was continued for 16 months. Large numbers of enzyme-altered foci developed when HOS was administered in the diet at levels of 0.05–0.25% to rats previously administered a single dose of N , N -diethylnitros-amine (DEN) 24 h after a 70% hepatectomy. Similarly, rats given a single dose of DEN 24 h after a partial hepatectomy and then fed 0.10 or 0.25% of HOS in the diet for 10 months developed a high incidence of hepatocellular carcinomas. In the absence of pretreatment with DEN, dietary administration for at least 4 months of 0.10 or 0.25% of HOS induced significant numbers of enzyme-altered foci; these data and liver tumor induction by continuous feeding of HOS, in the absence of pretreatment with DEN, provide additional evidence for an initiating, as well as a promoting, activity of HOS in rat liver. Concurrent administration of the hepatic sulfotransferase inhibitor pentachlorophenol with HOS in each of the above assays almost completely inhibited the initiating and promoting activities of HOS for the formation of enzyme-altered foci and tumors; these data strongly suggest that both the initiating and promoting activities are mediated by the sulfuric acid ester, 1′-sulfooxysafrole. HOS also exhibited initiating activity in adult mouse liver. Thus, dietary administration of 0.25% of HOS for only 1 month, followed by administration of the hepatic tumor promoter 1,4-bis[2-(3,5-dichloropyridyloxy)]benzene resulted in a high incidence and multiplicity of hepatomas by 10 months. In the absence of the promoter, administration of HOS for only 1 month induced no hepatomas; 1,4-bis[2-(3,5-dichloropyridyloxy)]benzene alone induced only a low incidence. In mice not given the promoter, continuous administration of HOS
Effects of separate and combined treatments with gamma radiation and diethylnitrosamine in neonatal rats on the induction of altered hepatocyte foci and hepatic tumors
Authors: Peraino Carl , Grdina David J. , Everett F. Staffeldt , Russell John J. , Prapuolenis Aldona , Carnes Bruce A. 
Published: January 2007

Abstract
To characterize the effects of combined treatments with gamma radiation and diethylnitrosamine (DEN) on the induction of histochemically detectable altered hepatocyte foci and hepatic tumors, we assessed the yields of these lesions in the livers of 150-day-old rats that had been treated neonatally with a single dose of gamma radiation (75 red, whole body) and i.p.-injected DEN (0.15 μmol/g body wt), either separately or in combination. The combined treatments involved the administration of the two stimuli in both possible sequences, with the interval between treatments set at 1 h. The focus population was examined for two histochemical markers (elevated gamma-glutamyl transpeptidase [GGT(+)J and iron exclusion [FE(−)], giving rise to three detectable focus phenotypes, i.e. GGT(+) foci, FE(−) foci, and GGT(+), FE(−) foci. Frequencies of the three phenotypes were quantitated through the use of serial frozen sectioning techniques and computer-assisted image analysis. GGT(+) focus induction was synergistkally enhanced by the combined treatment irrespective of the order in which the two stimuli were administered; the remaining two phenotypes did not show such enhancement. The magnitude of the GGT(+) focus response was significantly greater when the treatment sequence was gamma → DEN as opposed to DEN → gamma. Tumor yields in rats receiving combined gamma-DEN treatment were similar to those in rats receiving the DEN alone, irrespective of the gamma-DEN treatment sequence. These results suggest that (i) phenotypically distinguishable lesions, including foci with different histochemical marker patterns and tumors, originate from specific types of damage at different genetic loci and are developmentally independent; and (ii) the expression of the GGT(+) marker per se in altered hepatocyte foci is not a reliable index of incipient hepatic neoplasia.