bluuebunny/crossref_metadata_2025_split huggingface dataset:
Comparative evaluation of the efficacy of cereal and microbial phytases in growing pigs fed diets with marginal phosphorus supply
Authors: Zimmermann Birgit , Lantzsch Hans‐Joachim , Mosenthin Rainer , Schöner Franz‐Josef , Biesalski Hans Konrad , Drochner Winfried 
Published: October 2002

AbstractTwo experiments with a total of 76 growing pigs (average initial body weight 16.6 kg) were conducted to compare the efficacy of cereal phytases (wheat and rye) and supplemented microbial phytase (Natuphos®). Using the slope ratio technique, the dose–response relationship between five levels of phytase (0, 50, 100, 150 and 200 U kg−1) and the apparent absorption of phosphorus (P) within each source of phytase was calculated. Graded phytase levels in the diets were obtained by adding increasing amounts of microbial phytase or phytase‐containing wheat (Exp 1) or rye (Exp 2) to phytase‐inactivated basal diets at the expense of phytase‐inactivated wheat (Exp 1) or rye (Exp 2). Except for wheat phytase, addition of phytase to the basal diets increased (P < 0.05) apparent P absorption, with microbial phytase being more efficient (P < 0.05) than cereal phytase. There were no significant differences in apparent P absorption between the wheat‐ or rye‐based diets when either microbial or cereal phytases were supplemented from 0 to 200 U kg−1. It could be derived from the results of this study, by means of regression analysis, that the efficacy of cereal phytases was 40% compared to microbial phytase.© 2002 Society of Chemical Industry
A response surface methodology approach to optimise pretreatments to prevent enzymatic browning in potato (Solanum tuberosum L) cubes
Authors: Reyes‐Moreno C , Parra‐Inzunza M A , Milán‐Carrillo J , Zazueta‐Niebla J A 
Published: October 2002

AbstractThe objective of this work was to find the best combinations of ascorbic acid concentration/soaking time (Pretreatment 1), 4‐hexylresorcinol concentration/soaking time (Pretreatment 2) and ascorbic acid concentration–4‐hexylresorcinol concentration/soaking time (Pretreatment 3) to prevent the development of enzymatic browning in raw potato cubes (10 mm × 10 mm × 10 mm). Potato variety Alpha was used as study model because of its low susceptibility to enzymatic browning. Response surface methodology was applied in all pretreatments on two response variables (Hunter L value and total colour difference) to find the best conditions for carrying out the pretreatments. The various pretreatments had variation levels for ascorbic acid (AA) concentration (1 and 3) and 4‐hexylresorcinol (4HR) concentration (2 and 3) of 1–4 and 0.04–0.20 g l−1 respectively; in all pretreatments the variation level for soaking time was 3–6 h. A central composite experimental design with two factors at five levels was used. Predictive models for Hunter L value and total colour difference were developed as a function of process or independent variables. The optimisation technique was applied to obtain maximum Hunter L values and minimum values of total colour difference. Surface superposition of these variables allowed identification of the best combinations of process variables for each pretreatment as (1) 2.9 g l−1 AA/4.8 h, (2) 0.04 g l−1 4HR/2.6 h and (3) 2.42 g l−1 AA–0.15 g l−1 4HR/5.41 h.© 2001 Society of Chemical Industry
Kinetic study of the ruthenium(VI)‐catalyzed oxidation of benzyl alcohol by alkaline hexacyanoferrate(III)
Authors: Mucientes A. E. , Santiago F. , Almena M. C. , Poblete F. J. , Rodriguez‐Cervantes A. M. 
Published: October 2002

AbstractThe kinetics of the Ru(VI)‐catalyzed oxidation of benzyl alcohol by hexacyanoferrate(III), in an alkaline medium, has been studied using a spectrophotometric technique. The initial rates method was used for the kinetic analysis. The reaction is first order in [Ru(VI)], while the order changes from one to zero for both hexacyanoferrate(III) and benzyl alcohol upon increasing their concentrations. The rate data suggest a reaction mechanism based on a catalytic cycle in which ruthenate oxidizes the substrate through formation of an intermediate complex. This complex decomposes in a reversible step to produce ruthenium(IV), which is reoxidized by hexacyanoferrate(III) in a slow step. The theoretical rate law obtained is in complete agreement with all the experimental observations. © 2002 Wiley Periodicals, Inc. Int J Chem Kinet 34: 421–429, 2002
Acute electrophysiologic effect of pulsed gallium–arsenide low energy laser irradiation on configuration of compound nerve action potential and nerve excitability
Authors: Bagis Selda , Comelekoglu Ulku , Sahin Gunsah , Buyukakilli Belgin , Erdogan Canan , Kanik Arzu 
Published: October 2002

AbstractBackground and ObjectivesWe evaluated the acute electrophysiologic effects of low‐energy pulsed laser irradiation, measured by extracellular recording technique on compound action potential configuration and nerve excitability in the isolated frog sciatic nerveStudy Design/Materials and MethodsA pulsed gallium‐arsenide (GaAs) laser (wavelength, 904 nm; pulse duration, 220 nanoseconds; peak power per pulse, 27 W; spot size, 0.28 cm2; total applied energy density, 0.005–2.5 J/cm2) was used for the experiment. Sixty isolated nerves were divided into six groups (n = 10), each of which received a different repetition frequency. In each group, action potentials were recorded, before laser irradiation, which served as the control data. The extracellular action potentials were recorded for each combination of 1, 3, 5, 7, 10, 13, and 15 minutes of irradiation time and 4, 8, 16, 32, 64, 128 repetition frequency by using a BIOPAC MP 100 Acquisition System Version 3.5.7 (Santa Barbara USA). Action potential latency, duration of depolarization and repolarization, and the stimulating voltage were measured. Statistical evaluation was performed using linear correlation analysis by SPSS 9.05.ResultsAlthough there was no correlation between applied energy density and action potential latency, the duration of depolarization and repolarization phases (P > 0.05), there was a weak correlation between applied energy density and stimulating voltage.ConclusionsThe study showed that low‐energy GaAs irradiation at 42 different energy density between 0.005 and 2.5 J/cm2 generates no effect on action potential configuration and nerve excitability. Lasers Surg. Med. 30:376–380, 2002. © 2002 Wiley‐Liss, Inc.
Calcium solubility of dental enamel following sub‐ablative Er:YAG and Er:YSGG laser irradiation in vitro
Authors: Apel C. , Meister J. , Schmitt N. , Gräber H.‐G. , Gutknecht N. 
Published: October 2002

AbstractBackground and ObjectiveThe objective of the present study was to investigate the effect of sub‐ablative Er:YAG (λ = 2.94 μm) and Er:YSGG (λ = 2.79 μm) laser radiation on the acid solubility of dental enamel. The influence of fluoride application prior to laser irradiation was additionally evaluated.Study Design/Materials and MethodsTo this end, 294 enamel specimens were prepared from bovine teeth and divided into 14 groups of 21 specimens each. The enamel samples were irradiated in their groups with the Er:YAG and the Er:YSGG laser, using energy densities of 4, 6, and 8 J/cm2 in each case. Irradiation was additionally repeated in the same way on specimens, which had previously been immersed in 1% sodium fluoride solution for 15 minutes. One group was left untreated and served as a control group. A further group was not irradiated, but only immersed in the 1% fluoride solution for 15 minutes. The enamel specimens were demineralised for 24 hours in an acetate buffer solution. The calcium content in the demineralisation solution was subsequently determined with the aid of atomic absorption spectrometry.ResultsThe results indicate a decline in calcium solubility after laser irradiation. Compared to the control group, a 20% lower calcium content was detected in the demineralisation solution after irradiation with the Er:YSGG laser at 8 J/cm2. The difference between the laser‐irradiated groups and the untreated control group was, however, not statistically significant. A significantly lower calcium content was found in the demineralisation solution after fluoridation of the specimens. Additional laser radiation had no further effect on this result.ConclusionsIn summary, it can be stated that, although the erbium laser wavelengths apparently have the potential to increase acid resistance, their application solely for caries prevention would not appear to be sensible under the prevailing conditions. Lasers Surg. Med. 30:337–341, 2002. © 2002 Wiley‐Liss, Inc.
Tumorigenic effect of transcription factor hAP‐2α and the intricate link between hAP‐2α activation and squelching
Authors: Yu Yihong , Wang Yingqun , Li Min , Kannan Perry 
Published: October 2002

AbstractOverexpression of human activator protein‐2α (hAP‐2α) is carcinogenic. Its aberrant regulation is the underlying tumorigenic event in the human teratocarcinoma cell line PA‐1. In this cell line excess hAP‐2α protein binds and sequesters coactivators, which interferes with the activity of other activators and with its own activity. The N‐terminus of hAP‐2α, which contains an activation domain, is critical in squelching and tumorigenicity. Mutation analyses of the N‐terminus region showed that activation and squelching were intricately linked; nevertheless, squelching could occur in the absence of activity. Cells overexpressing squelching‐proficient mutants grew efficiently on soft agar irrespective of their ability to activate transcription, which indicates that these cells are tumorigenic. Mutants that lacked both properties were nontumorigenic. These results suggest that squelching, but not activation, causes transformation and that the factors that are sequestered at this region are critical in tumorigenesis. © 2001 Wiley‐Liss, Inc.
CpG hypermethylation of promoter region and inactivation of E‐cadherin gene in human bladder cancer
Authors: Ribeiro‐Filho Leopoldo Alves , Franks Joseph , Sasaki Masahiro , Shiina Hiroaki , Li Long‐Cheng , Nojima Dana , Arap Sami , Carroll Peter , Enokida Hideki , Nakagawa Masayuki , Yonezawa Suguru , Dahiya Rajvir 
Published: October 2002

AbstractSeveral studies have shown that E‐cadherin expression is lost during malignant transformation. We hypothesized that CpG methylation in the promoter region may inactivate the expression of the E‐cadherin gene in human bladder cancer. Normal and bladder cancer samples from 51 patients were compared in terms of E‐cadherin gene expression and methylation status by immunohistochemistry, methylation‐specific polymerase chain reaction (MSP), and bisulfite genome‐sequencing techniques. Ten different CpG sites (nt 863, 865, 873, 879, 887, 892, 901, 918, 920, and 940) in the promoter region were studied. Thirty‐five of 51 (69%) bladder cancer samples lacked E‐cadherin expression, whereas only six of 51 (12%) normal bladder samples lacked E‐cadherin immunoreactivity. MSP analysis of bladder cancer samples suggested that 43 of 51 (84%) showed methylation of the promoter region, whereas only 12 of 51 (24%) normal bladder samples showed hypermethylation. Sodium bisulfite genome‐sequencing analysis revealed that of 10 CpG sites, two sites (nt 892 and nt 940) showed 100% methylation in all the cancer samples analyzed. Other CpG sites were partially methylated (47–91%). Normal tissue showed only 12% methylation (range, 1–33%) on various CpG sites. Also supporting these data, E‐cadherin–negative bladder cancer cell lines restored expression of the E‐cadherin gene after treatment with the demethylating agent 5‐aza‐2′‐deoxycytidine. The present study showed that CpG hypermethylation was an important mechanism of E‐cadherin gene inactivation in bladder cancer and also that specific CpG sites consistently presented higher methylation levels than others. These findings may provide a better strategy for the diagnosis and management of bladder cancer. © 2002 Wiley‐Liss, Inc.
Reduced Brca1 protein expression in 2‐amino‐1‐methyl‐6‐phenylimidazo[4,5‐b]pyridine–induced rat mammary carcinomas
Authors: Okochi Eriko , Miyamoto Kazuaki , Wakazono Kuniko , Shima Hiroshi , Sugimura Takashi , Ushijima Toshikazu 
Published: October 2002

AbstractReduced expression of BRCA1 protein, caused by the hypermethylation of its gene promoter and by other mechanisms, is observed in most sporadic human breast cancers, whereas its somatic mutations are rare. In the present study, we demonstrate that immunoreactivity of Brca1 was reduced in almost all rat mammary carcinomas induced by 2‐amino‐1‐methyl‐6‐phenylimidazo[4,5‐b]pyridine (PhIP), whereas hypermethylation of its promoter, mutations in its entire coding region, and decreased mRNA expression were absent. Using two kinds of polyclonal antibodies against human BRCA1 that recognized the N and C termini, respectively, immunoreactivity of Brca1 was found to be reduced in all 17 carcinomas examined and, especially, to be almost completely lost in 8 or 10 carcinomas. The reduction was confirmed by immunoblot analysis of five mammary carcinomas and normal mammary epithelial cells. Sequencing of the Brca1 promoter region after bisulfite modification in 10 PhIP‐induced mammary carcinomas showed that the region was completely unmethylated in all of them. No mutations were detected in the entire coding region by direct sequencing of the Brca1 cDNA. Decrease in mRNA levels was not detected by quantitative real‐time reverse transcription–polymerase chain reaction. These data suggested that PhIP‐induced mammary carcinomas could model human breast cancers that show reduced BRCA1 immunoreactivity without promoter hypermethylation and with normal mRNA expression. As underlying mechanisms, alterations in posttranscriptional regulation or stability of Brca1 protein were suggested. © 2002 Wiley‐Liss, Inc.
The rise of human service chains: antecedents to acquisitions and their effects on the quality of care in US nursing homes
Authors: Banaszak‐Holl Jane , Berta Whitney B. , Bowman Dilys M. , Baum Joel A.C. , Mitchell Will 
Published: October 2002

AbstractThis paper studies acquisitions of nursing home facilities by chains. We first test alternative ‘cream‐skimming’ and ‘turn‐around’ arguments concerning nursing home acquisitions. We then consider post‐acquisition changes in nursing home health performance, differentiating effects of the acquisition process from those of prior strategy and performance of the acquired home and acquiring chain. Our dynamic empirical analysis of more than 5000 acquisitions by US nursing home chains from 1991 through 1997 shows that nursing home chain acquisitions are driven by a turn around logic, and that performance depends on the prior quality of the target and acquirer. Our analysis is relevant to policy on the nursing home sector, helping clarify why certain homes are acquired and how being acquired affects their residents' welfare. At a more general level, we offer insights concerning strategic factors that promote acquisition and drive expansion of service sector chains. Copyright © 2002 John Wiley & Sons, Ltd.
Five strategies for rapid firm growth and how to implement them
Authors: Mascarenhas Briance , Kumaraswamy Arun , Day Diana , Baveja Alok 
Published: October 2002

AbstractAnalysis of 45 rapidly growing, profitable firms reveals five strategies: (1) product proliferation, (2) mass market development, (3) increasing value to select customers, (4) distribution innovation, and (5) acquisition and consolidation. These five strategies are not restricted to high‐growth industries and arise when firms exploit market disequilibrium to the their advantage. The profitable growth strategies are based on multiple, reinforcing sources of scale, scope, and time‐based advantages. The study details the steps needed to implement each growth strategy and potential pitfalls to avoid. Copyright © 2002 John Wiley & Sons, Ltd.
Small‐Amplitude cortical myoclonus in Parkinson's disease: Physiology and clinical observations
Authors: Caviness John N. , Adler Charles H. , Beach Thomas G. , Wetjen Kristi L. , Caselli Richard J. 
Published: October 2002

AbstractWe studied the occurrence of small‐amplitude myo‐ clonus in 20 idiopathic Parkinson's disease patients who had no evidence of dementia as defined by criteria in the Diagnostic and Statistical Manual of Mental Disorders, fourth edition. Parkinson's disease was diagnosed by United Kingdom Brain Bank criteria, and clinical assessment was performed with the Unified Parkinson's Disease Rating Scale motor score, Hoehn and Yahr staging, and the Mini‐Mental State Examination. Clinical assessment showed a range of mild‐to‐moderate disease severity. All patients underwent polygraphic electro–encephalographic‐electromyographic (EMG) recording with back‐averaging, somatosensory evoked potential testing, and attempted elicitation of long‐latency EMG responses. Multichannel surface EMG recording during muscle activation showed irregular, multifocal, brief (<50 msec) myoclonus EMG discharges. Back‐averaging consistently showed a focal, short‐latency, electroencephalographic transient prior to the myoclonus EMG discharge. Cortical somatosensory evoked potential waves were not enlarged, and long‐latency EMG responses at rest were not present. The small‐amplitude myoclonus in such cases arises from an abnormal discharge from the sensorimotor cortex. The mechanism of this cortical myoclonus in Parkinson's disease has differences from the more common “cortical reflex myoclonus” physiology. Advanced parkinsonism is not a requirement for manifestation of this myoclonus type. Although the myoclonus occurred without dementia in these cases, its relationship to the subsequent development of cognitive impairment remains to be defined. © 2002 Movement Disorder Society
Secondary paroxysmal dyskinesias
Authors: Blakeley Jaishri , Jankovic Joseph 
Published: October 2002

AbstractParoxysmal dyskinesias (PxDs) are involuntary, episodic movements that include paroxysmal kinesigenic (PKD), paroxysmal nonkinesigenic (PNKD), and paroxysmal hypnogenic (PHD) varieties. Although most PxDs are primary (idiopathic or genetic), we found 17 of our 76 patients with PxD (22%) to have an identifiable cause for their PxD (10 men; mean age, 41.4 years). Causes included peripheral trauma (in three patients), vascular lesions (in four), central trauma (in four), kernicterus (in two), multiple sclerosis (in one), cytomegalovirus encephalitis (in one), meningovascular syphilis (in one), and migraine (in one). The latency from insult to symptom onset ranged from days (trauma) to 18 years (kernicterus), with a mean of 3 years. Nine patients had PNKD, two had PKD, five had mixed PKD/PNKD, and one had PHD. Hemidystonia was the most common expression of the paroxysmal movement disorder, present in 11 patients. Both of the patients with PKD had symptom durations of <5 minutes. Symptom duration ranged from 10 seconds to 15 days for PNKD and from 5 minutes to 45 minutes for mixed PKD/PNKD. There were no uniformly effective therapies, but anticonvulsant drugs, clonazepam, and botulinum toxin injections were the most beneficial. Awareness of the variable phenomenology and the spectrum of causes associated with secondary PxD will allow for more timely diagnosis and early intervention. © 2002 Movement Disorder Society
Tourettism and dystonia after subcortical stroke
Authors: Kwak Carolyn H. , Jankovic Joseph 
Published: October 2002

AbstractThe term “tourettism” has been used to describe Tourette syndrome (TS)‐like symptoms secondary to some specific cause. Tics associated with attention deficit hyperactivity disorder (ADHD), obsessive–compulsive disorder (OCD), or both, are commonly present in TS, but this constellation of symptoms has been rarely attributed to stroke. We describe two boys who suffered a subcortical stroke and subsequently developed hemidystonia, tics, and behavioral comorbidities. Both had right hemispheric stroke involving the basal ganglia at 8 years of age, and in both the latency from the stroke to the onset of left hemidystonia was 2 weeks. In addition to ADHD and OCD, both exhibited cranial‐cervical motor tics but no phonic tics. The temporal relationship between the stroke and subsequent TS‐like symptoms, as well as the absence of phonic tics and family history of TS symptoms in our patients, argues in favor of a cause and effect relationship, and the observed association provides evidence for an anatomic substrate for TS and related symptoms. © 2002 Movement Disorder Society
Chloroquine resistance in the malarial parasite, Plasmodium falciparum
Authors: Ursos Lyann M.B. , Roepe Paul D. 
Published: October 2002

AbstractMalarial parasites remain a health problem of staggering proportions. Worldwide, they infect about 500 million, incapacitate tens of millions, and kill approximately 2.5 million (mostly children) annually. Four species infect humans, but most deaths are caused by one particular species, Plasmodium falciparum. The rising number of malarial deaths is due in part to increased drug resistance in P. falciparum. There are many varieties of antimalarial drug resistance, and there may very well be several molecular level contributions to each variety. This is because there are a number of different drugs with different mechanisms of action in use, and more than one molecular event may sometimes be relevant for resistance to any one class of drugs. Thus, “multidrug” resistance in a clinical setting likely entails complex combinations of overlapping resistance pathways, each specific for one class of drug, that then add together to confer the particular multidrug resistance phenotype. Nonetheless, rapid progress has been made in recent years in elucidating mechanisms of resistance to specific classes of antimalarial drugs. As one example, resistance to the antimalarial drug chloroquine, which has been the mainstay therapy for decades, is becoming well understood. This article focuses on recent advances in determining the molecular mechanism of chloroquine resistance, with particular attention to the biochemistry and biophysics of the P. falciparum digestive vacuole, wherein changes in pH have recently been found to be associated with chloroquine resistance. © 2002 Wiley Periodicals, Inc. Med Res Rev, 22, No. 5, 465–491, 2002; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/med.10016
Experimental study of a broadband U‐slot triangular patch antenna
Authors: Jang Yong‐Woong 
Published: October 2002

AbstractThis Letter describes a U‐shaped aperture‐coupled U‐slot triangular patch antenna fed by microstrip feed line. Because a thick aperture substrate with a dual U‐slot patch radiator are used in the design, a high level of coupling to the feed line results. The measured bandwidth of approximately 84.9% (VSWR ≤ 2.0) and a gain of 6.5 dBi have been obtained. The experimental far‐field patterns are stable across the passband. © 2002 Wiley Periodicals, Inc. Microwave Opt Technol Lett 34: 325–327, 2002; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.10451