bluuebunny/crossref_metadata_2025_split huggingface dataset:
Tissue histopathology, clinical chemistry and behaviour of adult comt‐gene‐disrupted mice
Authors: Haasio Kristiina , Huotari Marko , Nissinen Erkki , Männistö Pekka T. 
Published: July 2003

AbstractCatechol‐O‐methyltransferase (COMT) enzyme is a widely distributed enzyme that catalyses O‐methylation of catecholamines and other compounds having a catechol structure. Because there has been some concern about the consequences of a low COMT activity in the development of oestrogen‐dependent cancers and because one of the COMT inhibitors, tolcapone, has caused serious liver injuries in Parkinsonian patients, the histopathology and clinical chemistry of Comt‐gene‐disrupted mice were studied at the age of 12 months. Owing to the high COMT activities in liver and kidney and the role of COMT in the metabolism of catechol oestrogens, special emphasis was given to the histology of the liver, kidney and oestrogen‐dependent organs such as mammary glands and uterus.The mice of both heterozygous and homozygous genotypes appear to be physically healthy and fertile. Diurnal motility rhythm and behaviour in measuring anxiety and depression were equal in all genotypes. At the age of 12 months, the body weight of homozygous mice was 7–9% lower than that of the other groups. This was reﬂected in histology as a diminished incidence of vacuolation of liver cells (fatty change). Macroscopic pathology and histopathology revealed no abnormal ﬁndings in any COMT genotype. The values of some clinical chemistry parameters, such as alkaline phosphatase, alanine aminotransferase, urea, glucose, calcium and proteins, were at a higher level in homozygous animals compared with the wild‐type mice. However, all the values remained within the normal physiological range, and the differences in enzyme levels between genotypes were not reﬂected as histopathological ﬁndings in the relevant organs. No changes in haematological parameters or plasma catecholamine concentrations were noted but plasma 3,4‐dihydroxyphenylethylene glycol levels were high in COMT null mice.The results suggest that the full or 50% lack of Comt gene as such is not associated with any toxic consequences. Copyright © 2003 John Wiley & Sons, Ltd.
Apoptosis induced by different doses of caffeine on Chinese hamster ovary cells
Authors: Fernández M. J. , López A. , Santa‐Maria A. 
Published: July 2003

AbstractCaffeine has been investigated for its potential mutagenic activity to bacteria, fungi and mammalian cells in culture, and at high concentrations it is also an inducer of apoptosis. Caffeine can exert acute cellular toxicity, including inhibition of cell growth and cell death, in Chinese hamster ovary cells.The aim of this study was to evaluate the cell survival and apoptotic or non‐apoptotic effects of caffeine to different concentrations in Chinese hamster ovary cells (CHO‐K1). These effects were evaluated by measuring cell viability, caspase 8 activity and fragmented DNA. This study suggests that the concentration of caffeine is of critical importance because high doses of caffeine induce apoptosis and low concentrations can act as an antioxidant.Previously, the cytotoxicity of caffeine was evaluated using a wide range of concentrations by the neutral red test. From this screening, adequate doses were selected to perform the caspase activity and fragmentation DNA studies. The potential antioxidant effect of caffeine was studied using tert‐butyl‐hydroperoxide as a free‐radical generator. The repeatability was checked through three separate tests with the same concentration. Copyright © 2003 John Wiley & Sons, Ltd.
Degradation of VX and sulfur mustard by enzymatic haloperoxidation
Authors: Amitai G. , Adani R. , Hershkovitz M. , Bel P. , Rabinovitz I. , Meshulam H. 
Published: July 2003

AbstractChloroperoxidase (CPO) isolated from Caldariomyces fumago (20 U ml−1) together with urea hydrogenperoxide (UPER, 0.5 mM) and sodium chloride as co‐substrate (NaCl, 0.5 M) caused rapid breakdown of VX (10 µM) (t½ = 8 s, 25 C, 50 mM tartarate, pH 2.75). Glucose oxidase (GOX, Aspergillus niger) and glucose were used as an alternative source for H2O2. A mixture of GOX (20 U ml−1), glucose (GLU 0.45 M), CPO (20 U ml−1) and NaCl (0.5 M) caused a 3.8‐fold slower degradation of VX (10 µM) (t½ = 30 s, 25 C, 50 mM tartarate, pH 2.75). The concentrations of H2O2 and chlorine produced by this enzyme/substrate mixture depended mainly on the GLU concentration. Horseradish peroxidase (HRP) together with UPER (1 mM) and sodium iodide (NaI, 0.05 M) caused progressive degradation of VX that was more than 400‐fold slower than with CPO (20 U ml−1), UPER (0.5 mM) and NaCl (0.5 M) (t½ = 55 min, 25 C, pH 8). Skin decontamination of VX by CPO was tested in pig‐ear skin in vitro. The chemical agent VX (0.01 M, 100 µl) was degraded by 98% within 3 h of skin diffusion when a mixture of UPER/NaCl/CPO was applied 60 min prior to VX application. A mixture of UPER/NaCl without CPO also caused signiﬁcant VX degradation (94%) during skin diffusion whereas it did not cause any VX degradation in solution. Degradation of VX in skin, obtained without exogenous CPO, may indicate involvement of endogenous intradermal haloperoxidase‐like enzyme. Reagent UPER (1 mM) did not cause any degradation of VX in solution or during its skin diffusion. Furthermore, a mixture of CPO, UPER and NaCl caused rapid degradation of sulfur mustard (HD). Sulfur mustard (50 µM) incubated in the presence of CPO (4 U ml−1), UPER (0.05 M) and NaCl (0.5 M) at pH 2.75 and 30 C was oxidized by 97% and 99% within 5 and 10 min, respectively. The oxidation products HD sulfoxide, HD sulfone and HD sulfoxidevinyl were identiﬁed by GC/MS in the enzymatic chloroperoxidation mixture. Copyright © 2003 John Wiley & Sons, Ltd.
Leydig cell death in rats exposed to bismuth subnitrate
Authors: Pedersen Lars H. , Stoltenberg Meredin , Ernst Erik , West Mark J. 
Published: July 2003

AbstractIn a previous study, rats were treated with one injection of 500 mg kg−1 bismuth subnitrate intraperitoneally and maintained for 2 weeks. Bismuth was observed in Leydig cells, with a subsequent reduction in serum testosterone levels. In the present study, stereological procedures were used to estimate the number of Leydig cells in the right testis from the retained rats used in the previously published study.The mean number of Leydig cells in the control group was estimated to be 18.7 × 106 (coefﬁcient of variation = 0.11), which is comparable to previous estimations. In the group exposed to bismuth the mean was 15.5 × 106 (coefﬁcient of variation = 0.18). The observed 17% difference between the two groups was statistically signiﬁcant (2P = 0.019). The inter‐individual variation was largest in the bismuth‐exposed group. Testis weight and body weight were not signiﬁcantly reduced after bismuth exposure.These ﬁndings support the hypothesis that bismuth has a direct toxic effect on rat Leydig cells and underscores the potential risks of bismuth on male reproduction. Copyright © 2003 John Wiley & Sons, Ltd.
Iron status in manganese alloy production workers
Authors: Ellingsen Dag G. , Haug Egil , Ulvik Rune J. , Thomassen Yngvar 
Published: July 2003

AbstractThe aim of this study was to investigate markers of iron status in production workers with current and long‐term exposure to manganese (Mn) alloys. A total of 100 Mn‐exposed male workers were compared with 100 male controls matched for age in a cross‐sectional study. The geometric mean urinary Mn concentration in the exposed workers was 0.9 nmol mmol−1 creatinine (range = 0.1–126.3), compared with 0.4 nmol mmol−1 creatinine (range = 0.1–13.1) in the controls. The index group had been exposed to Mn for 20 years on average (range = 2.1–41.0). The geometric mean concentration of soluble transferrin receptor was lower in the exposed subjects than in the controls (2.2 vs 2.6 mg l−1; P < 0.001) and the concentration was negatively associated with current exposure to ‘soluble’ Mn in the inhalable aerosol fraction and with current smoking habits. An association was found between the concentration of serum soluble transferrin receptor and the concentration of Mn in whole blood (Pearson's r = 0.48; P < 0.001) in the controls. The results suggest that Mn‐exposed workers have higher intracellular iron concentration in the erythrocyte precursors than the controls, resulting in a down‐regulation of transferrin receptors on the surface of these cells. The concentrations of Mn in the blood of occupationally non‐exposed individuals appear to be inﬂuenced by iron status, even at physiological iron levels. Copyright © 2003 John Wiley & Sons, Ltd.
Effects of sulfur mustard on transcription in human epidermal keratinocytes: analysis by mRNA differential display
Authors: Platteborze Peter L. 
Published: July 2003

AbstractThis study examines the transcriptional response of human epidermal keratinocytes (HEK) to sulfur mustard (HD) in order to gain a better understanding of the intracellular events that result in cytotoxicity. Differential display polymerase chain reaction technology was used to examine the relative transcriptional activity of healthy cells to those exposed to subvesicating or vesicating concentrations of HD for 4 h. Approximately 2% of the HEK transcriptome had altered expression. Sixty of the most prominently altered transcripts were characterized. Important upregulated genes include NADH dehydrogenase III, GADD45 and ubiquitin. Key downregulated genes include type I keratin 14, α‐enolase and caltractin. Many of the identiﬁed transcripts protein products presently do not have an assigned function and eleven transcripts were unidentiﬁable. These transcriptional alterations provide one of the ﬁrst molecular insights into the intracellular events induced by HD. Published in 2003 by John Wiley & Sons, Ltd.
Resveratrol, a natural aryl hydrocarbon receptor antagonist, protects lung from DNA damage and apoptosis caused by benzo[a]pyrene
Authors: Revel Ariel , Raanani Hila , Younglai Edward , Xu Jing , Rogers Ian , Han Robin , Savouret Jean‐Francois , Casper Robert F. 
Published: July 2003

AbstractBenzo[a]pyrene (BaP) is an agonistic ligand for the aryl hydrocarbon receptor (AhR) and a major environmental carcinogen implicated in the aetiology of lung cancer through the induction of benzo[a]pyrene diol epoxidation (BPDE) and BPDE–DNA adducts. Because BaP metabolization requires cytochrome P‐450 1A1 (CYP1A1) induction through activation of the AhR, we hypothesized that resveratrol, a natural competitive inhibitor of AhR, could prevent these adverse effects of BaP on the lung. Balb‐C mice were injected for 5 weeks with corn oil, BaP (5 mg kg−1 week−1), resveratrol (50 mg kg−1 week−1) or BaP + resveratrol. Immunohistochemistry was performed on lung sections for the determination of CYP1A1 protein, BPDE–DNA adducts and apoptosis. A semi‐quantitative immunohistochemistry score (H score) was used for data analysis. Mice exposed to BaP had a signiﬁcant induction of lung BPDE–DNA adducts when compared with controls (H scores: control, 26, interquartile range 18–33; BaP, 276, interquartile range 269–288; P < 0.01). The BPDE–DNA adduct induction by BaP was abrogated signiﬁcantly by resveratrol (H score: BaP + resveratrol, 103, interquartile range 96–113). A similar pattern was found by immunohistochemistry for apoptosis (H scores: control, 121, interquartile range 102–137; BaP, 288, interquartile range 282–292, P < 0.05; BaP + resveratrol, 132, interquartile range 121–141, P = NS) and CYP1A1 (H scores: control, 170.3, interquartile range 164–175; BaP, 302.3, interquartile range 291–315, P < 0.05; BaP + resveratrol, 200.7, interquartile range 174–215, P = NS). Western blotting conﬁrmed that resveratrol prevented BaP‐induced CYP1A1 expression. This increase in CYP1A1 expression in response to BaP administration most likely causes BaP metabolism, BPDE–DNA adduct formation and subsequent apoptosis. All BaP‐induced effects could be prevented by resveratrol, suggesting a possible chemopreventive role for this natural phytoalexin against the development of lung cancer. Copyright © 2003 John Wiley & Sons, Ltd.
Harmonization of thresholds for primary skin irritation from results of human repeated insult patch tests and laboratory animal skin irritation tests
Authors: Tardiff Robert G. , Hubner Richard P. , Gevecker Graves Carol 
Published: July 2003

AbstractClassiﬁcation of a chemical or chemical product as a primary skin irritant using laboratory animal tests has been deﬁned rigorously and codiﬁed in Consumer Products Safety Commission (CPSC) regulations. However, no regulatory agency, including the CPSC, has deﬁned a primary skin irritant threshold for human rapeat insult patch tests (RIPTs) that are typically conducted on products, such as cosmetics, anticipated to come into direct contact with humans. Further more, the protocols for animal and human tests are signiﬁcantly different, as are the schemes for grading responses. Consequently, comparing the results of one type of test with those from the other type has proved to be difﬁcult. In this short communication, we propose a procedure to harmonize the results from these two types of skin irritation tests and suggest that a score of ‘5’ in animal tests, considering 24‐h results on unabraded skin, is equivalent to a score of ‘3’ in human RIPTs. Copyright © 2003 John Wiley & Sons, Ltd.
Neurotoxic character of thimerosal and the allometric extrapolation of adult clearance half‐time to infants
Authors: Magos L. 
Published: July 2003

AbstractThe decomposition rate of organomercurials and the potency of the blood–brain barrier increase with the size of the organic radical. Thus methylmercury damages the brain more than thimerosal does, and when intake limits set for methylmercury are applied to thimerosal the safety margin is increased even if the clearances were the same. However, the clearance half‐time of ethylmercury in adults is about one‐third of the 50 days' clearance half‐time of methylmercury given for 60 kg body weight. Moreover, because metabolic rates (e.g. basal metabolism, daily loss of mercury in per cent of body burden) in different weight groups are related to the fractional power of body weight (rule of allometry), mercury clears from the infant body faster than from the adult body. Blood mercury concentrations observed after vaccination showed agreement with allometrically extrapolated concentrations. Copyright © 2003 John Wiley & Sons, Ltd.
Testicular and spermatotoxic effects of quinalphos in rats
Authors: Pant N. , Srivastava S. P. 
Published: July 2003

AbstractTesticular and spermatotoxic effects were investigated in rats exposed to technical‐grade quinalphos (70%) at dose levels of 0.52 mg kg−1 (1/50th ld50) or 1.04 mg kg−1 body weight (1/25th ld50) for 5 days a week for 60 days. The activities of marker testicular enzymes such as sorbitol dehydrogenase (SDH) and acid phosphatase were signiﬁcantly decreased but those of lactate dehydrogenase (LDH), γ‐glutamyl transpeptidase (γ‐GT) and β‐glucuronidase were signiﬁcantly increased in a dose‐dependent manner. This particular pattern in the activity of testicular‐cell‐speciﬁc enzymes, an decrease in sperm motility and total epididymal sperm count and an increase in abnormal sperm suggest damage to germ cells and Sertoli cells. The testicular and spermatotoxic effects observed in rats may be due to the pesticide quinalphos or its metabolites. Copyright © 2003 John Wiley & Sons, Ltd.
Insights into the mechanism of erythrocyte Na+/K+‐ATPase inhibition by nitric oxide and peroxynitrite anion
Authors: Muriel Pablo , Castañeda Gilberto , Ortega Mónica , Noël François 
Published: July 2003

AbstractEvidence shows that Na+/K+‐ATPase from kidney, brain and liver is inhibited by nitric oxide (NO) and peroxynitrite anion (ONO2−), but the mechanism is unknown. The aim of the present work was to study the inhibitory effect of NO and ONO2− on erythrocyte Na+/K+‐ATPase. Erythrocyte membranes were isolated from male Wistar rats by hypotonic washing. The membranes (free from haemoglobin) were incubated for Na+/K+‐ATPase activity measurement at various concentrations of ATP in the presence or absence of 400 µM SNAP (an NO donor) or 100 µM SIN‐1 (an ONO2− donor). At these concentrations, SNAP and SIN‐1 released about the same amount (100 µM) of NO or ONO2−, respectively, as monitored by measuring NO2− + NO3−. Both SNAP and SIN‐1 decreased Vmax by ca. 75% but they did not decrease the apparent afﬁnity of the Na+/K+‐ATPase for the substrate (a decrease of Km was even observed after SNAP treatment). The pattern of this inhibition is compatible either with oxidation of SH groups directly involved in ATP binding but in a way that is not surmountable by increasing the substrate concentration (‘non‐competitive’) or with oxidation of SH groups located outside the active site of the enzyme but important for the activity of the enzyme. Copyright © 2003 John Wiley & Sons, Ltd.
Replication of a psychosocial rehabilitation program: A case study analysis of supported education
Authors: Mowbray Carol T. , Gutierrez Lorraine M. , Bellamy Chyrell D. , Szilvagyi Steve , Strauss Shari 
Published: July 2003

AbstractThis article describes a strategy of organizing community stakeholder groups for the purpose of planning and implementing an innovative mental health program—supported education services for adults with mental illnesses who were interested in pursuing postsecondary education. A common planning framework was used in several different communities within the same state. The framework is described, as well as each community's characteristics and their planning and development activities—those typically identified in the literature as predictors of successful innovation diffusion efforts. We then present the outcomes of the planning process in each community and suggest conclusions about which community characteristics and/or planning activities seem to be most associated with success. © 2003 Wiley Periodicals, Inc. J Comm Psychol 31: 437–457, 2003.
Interdisciplinary collaboration: An ongoing community narrative
Authors: Roos Vera , Lombard Antoinette 
Published: July 2003

AbstractThe current social problems in South Africa demand new levels of thinking, intervention, and educational and training models. We describe here how different disciplines of the Faculty of Humanities, University of Pretoria, collaborated in co‐creating opportunities for children living on the street by applying the principles of participatory action research. Cooperation among various disciplines is possible in a training and research context as well as in community interventions. Data for reflecting on the process was obtained from formal policy documents of the faculty as well as through accounts drawn from many of the participants involved. Interdisciplinary collaboration is more likely to occur if there is a continuous sharing of ideas and support of intrinsic creativity among all members involved. © 2003 Wiley Periodicals, Inc. J Comm Psychol 31: 543–552, 2003.
Effectiveness of day treatment with proctor care for young children: A four‐year follow‐up
Authors: Whitemore Erin , Ford Monica , Sack William H. 
Published: July 2003

AbstractThis study evaluated the immediate and long‐term outcomes of a day treatment and proctor care model for preschool‐aged children. Seventy‐seven boys and 52 girls completed the program which combined day treatment, case management, individual and family therapy. Also, 60% of these clients were placed in proctor care homes which are short‐term family placements providing in‐home treatment. Results showed there was increased stabilization in family placements, with 67% of participants still living in a permanent family placement at the 4‐year follow‐up. Also, 69% of participants transitioned to a less‐restrictive academic placement and remained in regular classroom placements at follow‐up. Participants showed significant behavioral improvement at discharge and follow‐up on the Child Behavior Checklist. Participants also showed significant developmental improvement on the Battelle Developmental Inventory and the Expressive One Word Vocabulary Test. The results suggest that this treatment modality is effective in maintaining these children in the community and in producing positive long‐term outcomes. © 2003 Wiley Periodicals, Inc. J Comm Psychol 31: 459–468, 2003.
Helpseeking behavior among Filipino Americans: A cultural analysis of face and language
Authors: Gong Fang , Gage Sue‐Je L. , Tacata Leonardo A. 
Published: July 2003

AbstractIn this study we explore the existing research on Asian Americans and helpseeking behavior, focusing primarily on Filipino Americans and the cultural variables of face and language. Although some important and specific cultural factors have been hypothesized to affect the helpseeking behaviors of ethnic minorities, very few empirical studies have been conducted to specifically test these hypotheses. To fill the gaps in previous research, we examined the influence of concern with face and of language abilities on helpseeking behavior for mental health problems among Filipino Americans. In addition, to obtain a more comprehensive understanding of helpseeking behavior, we divided the mental health care systems into four categories: lay, mental health specialty, general practitioner, and folk systems. Data are from the Filipino American Epidemiological Study (FACES) survey. The main statistical method we employed was logistic regression. Results from the descriptive analyses reveal that the lay system is the most frequently used source of care compared with the other systems of professional and folk systems for Filipino Americans. Furthermore, findings from the main effects models suggest that face and language are important cultural factors that contribute to the helpseeking behavior of Filipino Americans, but they have different influences on the four types of mental health care systems. The interaction analyses indicate that concern with face interacts with language abilities when predicting use of the lay system and the general medical sector. Despite these findings, to fully understand the dynamics of helpseeking, other cultural factors and longitudinal studies are needed. © 2003 Wiley Periodicals, Inc. J Comm Psychol 31: 469–488, 2003.
The role of resource, protective, and risk factors on academic achievement‐related outcomes of economically disadvantaged Latino youth
Authors: Prelow Hazel M. , Loukas Alexandra 
Published: July 2003

AbstractWe examined the effects of cumulative risk, resource, and protective factors on the language and math achievement scores and school problem behaviors of a sample of 549 10–14‐year‐old, economically disadvantaged Latino youths. Findings indicated that as the number of risk factors increased, youth's language and math achievement scores decreased and school problem behaviors increased. Hierarchical regression analyses revealed that each of the hypothesized resource variables (i.e., maternal monitoring, maternal academic involvement, socioemotional competence, and extracurricular activity) made a unique contribution to at least one achievement‐related outcome, over and above the effects of cumulative risk. Moreover, maternal monitoring buffered the effects of multiple risk factors on language achievement scores. Contrary to expectations, higher levels of participation in extracurricular activities had a detrimental effect on male school problem behavior scores and was unrelated to girl's problem behavior scores. © 2003 Wiley Periodicals, Inc. J Comm Psychol 31: 513–529, 2003.