bluuebunny/crossref_metadata_2025 huggingface dataset:
Preliminary Assessment of Refrigerated and Frozen Storage of Sperm of the Coppernose Bluegill
Authors: Bates Mark C , Williams Casey S , Lang R Paul , Tiersch Terrence R
Published: June 2005

The coppernose bluegill (CBG) Lepomis macrochirus purpurescens is a bluegill subspecies that is native to Florida. The CBGs and their hybrids are of interest as potential food fish. Our objectives were to (1) develop an osmolality activation curve for CBG sperm, (2) determine suitable cryoprotectants for the cryopreservation of CBG sperm, and (3) demonstrate the ability of cryopreserved CBG sperm to fertilize eggs. Sperm were stripped from mature CBGs (mean ± SD = 113 ± 35 g, n = 10), diluted in Hanks' balanced salt solution (HBSS; osmolality = 300 mosmols/kg), and stored at 4°C. An activation curve was generated by exposing the sperm to solutions prepared by serial dilution of HBSS with de-ionized water. The sperm remained inactive at osmolalities above 265 mosmols/kg. Dilution below 115 mosmols/kg was required for complete activation. The motility of sperm stored in these solutions was estimated at 24-h intervals. Stripped sperm motility (mean ± SD) declined from 90 ± 7% initially to 26 ± 11% after 6 d of storage at 4°C. Motility of sperm from crushed testes declined from 80 ± 8% at collection to 28 ± 10% at 1 d of storage. By day 5, motility of sperm from crushed testes was 9 ± 9%; no motility was observed at 6 d. Sperm were exposed to 10% concentrations of the cryoprotectants dimethyl acetamide (DMA), dimethyl sulfoxide (DMSO), and methanol (MeOH), and motility was evaluated at 15-min intervals for 60 min. Initially, motility was 81 ± 11% for the control sperm. At 60 min, motility was 0% for DMA, 30 ± 24% for DMSO, 78 ± 10% for MeOH, and unchanged for the control. For samples frozen in a controlled-rate freezer (CRF), post-thaw motility was 26 ± 10% for samples with 10% DMSO and 51 ± 18% for samples with 10% MeOH. For samples frozen by means of dairy industry technology (DIT), post-thaw motility was 46 ± 21% for samples with 10% DMSO and 56 ± 13% for samples with 10% MeOH. Overall, samples frozen in 10% MeOH had significantly higher post-thaw motility (P = 0.043) than did those frozen in 10% DMSO. However, post-thaw motility did not differ between samples frozen by use of the CRF and DIT (P = 0.13). For sperm frozen in the CRF, fertilization was 15% for samples with 10% DMSO and 50% for samples with 10% MeOH. For sperm frozen by means of DIT, fertilization was 50% for samples with 10% DMSO and 75% for samples with 10% MeOH.
Evaluation of Hatchery versus Wild Sockeye Salmon Fry Growth and Survival in Two British Columbia Lakes
Authors: Hyatt Kim D. , Mathias Karin L. , McQueen Donald J. , Mercer Brian , Milligan Patrick , Rankin D. Paul
Published: June 2005

We evaluated the relative success of sockeye salmon hatchery fry stocking in two British Columbia–Alaska transboundary lakes (1,622-ha Tatsamenie Lake and 492-ha Tahltan Lake). Fry stocking began in the late 1980s and is still under way. During the study period, survival patterns in the two lakes were different. At Tatsamenie Lake, wild egg-to-fry survival was higher than hatchery egg-to-fry survival (11.3% versus 4.3%) and wild egg-to-smolt survival was higher than hatchery egg-to-smolt survival (5.8% versus 2.5%). We found no relationship between fry survival and stocking date, spawner abundance, or food availability in Tatsamenie Lake, but we did find a significant positive relationship between early-spring fry length and egg-to-fry survival. Also, we found that in net-pen experiments, larger fry survived better. From this, we concluded that hatchery fry stocked into Tatsamenie Lake may suffer from size-mediated mortality and that net-pen supplemental feeding could be used to overcome this problem. However, because eggs used for hatchery production come from the lake, fry stocking can only be justified when hatchery fry survival exceeds wild fry survival. At Tatsamenie Lake, this goal has not yet been attained. At Tahltan Lake, wild egg-to-fry survival was lower than hatchery egg-to-fry survival (1.5% versus 6.3%) and wild egg-to-smolt survival was lower than hatchery egg-to-smolt survival (3.6% versus 12.8%). Hatchery fry release date and food availability both failed to explain these differences in fry and smolt survival at Tahltan Lake. However, there was a strong negative relationship between total female escapement and wild egg-to-smolt survival. This supported the results of an earlier investigation, which suggested that Tahltan Lake was spawning-site limited. We concluded that at Tahltan Lake, hatchery fry stocking increased smolt numbers, is biologically justified, and should be continued.
Suppressor of cytokine signalling (SOCS) genes are expressed in the endometrium and regulated by conceptus signals during early pregnancy in the ewe
Authors: Sandra Olivier , Bataillon Isabelle , Roux Pascale , Martal Jacques , Charpigny Gilles , Reinaud Pierrette , Bolifraud Philippe , Germain Guy , Al-Gubory Kaïs H
Published: June 2005

It is established that the conceptus–endometrium dialogue involves cytokines, growth factors and hormones. Given the crucial functions of the suppressor of cytokine signaling (SOCS) family proteins in cytokine signalling, we analyzed the expression and the regulation of CIS and SOCSs 1–3 transcripts during early pregnancy in the ovine endometrium. An overall stimulation of the SOCS transcripts was described in the pregnant ewes with two specific patterns. Unilaterally pregnant ewes confirmed the conceptus-produced factors as regulators of the SOCSs 1–3 expression at day 16 of pregnancy. Intrauterine injection of recombinant ovine interferon τ (IFNτ) in cyclic ewes stimulated the expression of the SOCS mRNA with various potencies, therefore suggesting that the SOCS could take part in the negative regulation of the IFNτ signalling pathway.
An arachidonic acid-preferring acyl-CoA synthetase is a hormone-dependent and obligatory protein in the signal transduction pathway of steroidogenic hormones
Authors: Cornejo Maciel Fabiana , Maloberti Paula , Neuman Isabel , Cano Florencia , Castilla Rocío , Castillo Fernanda , Paz Cristina , Podestá Ernesto J
Published: June 2005

We have described that, in adrenal and Leydig cells, the hormonal regulation of free arachidonic acid (AA) concentration is mediated by the concerted action of two enzymes: an acyl-CoA thioesterase (MTE-I or ARTISt) and an acyl-CoA synthetase (ACS4). In this study we analyzed the potential regulation of these proteins by hormonal action in steroidogenic cells. We demonstrated that ACS4 is rapidly induced by adrenocorticotropin (ACTH) and cAMP in Y1 adrenocortical cells. The hormone and its second messenger increased ACS4 protein levels in a time and concentration dependent way. Maximal concentration of ACTH (10 mIU/ml) produced a significant effect after 15 min of treatment and exerted the highest increase (3-fold) after 30 min. Moreover, 35S-methionine incorporation showed that the increase in ACS4 protein levels is due to an increase in the de novo synthesis of the protein. On the contrary MTE-I protein levels in Y1 and MA-10 cells did not change after steroidogenic stimuli. In contrast with the effect observed on protein levels, stimulation of both cell lines did not change ACS4 RNA levels during the first hour of treatment, indicating that the effect of both stimuli is exerted at the level of ACS4 protein synthesis.

StAR protein induction has a key role on the activation of steroidogenesis since this protein increases the rate of the limiting step of the whole process. In agreement with the fact that the inhibition of ACS4 activity by triacsin C blocks cAMP-stimulated progesterone production by MA-10 Leydig cells, here we demonstrated that ACS4 inhibition also reduces StAR protein levels. Moreover, exogenous AA was able to overcome the effect of triacsin C on both events, StAR induction and steroidogenesis. These results were confirmed by experiments using ACS4-targeted siRNA which result in a reduction in both ACS4 and StAR protein levels. The concomitant decrease in steroid production was overcome by the addition of AA to the knocked-out cells. In summary, this study suggests that in adrenal and Leydig cells the hormonal action prompts the synthesis of a labile protein, ACS4, which activity is involved in the regulation of AA release and is essential for steroidogenesis and StAR protein induction.
IGF-I and vasoactive intestinal peptide (VIP) regulate cAMP-response element-binding protein (CREB)-dependent transcription via the mitogen-activated protein kinase (MAPK) pathway in pituitary cells: requirement of Rap1
Authors: Fernández M , Sánchez-Franco F , Palacios N , Sánchez I , Cacicedo L
Published: June 2005

In previous studies we demonstrated that vasoactive intestinal peptide (VIP) mediation, and interactions between mitogen-activated protein kinase (MAPK) and cAMP/protein kinase A (PKA) signaling pathways are implicated in insulin-like growth factor I (IGF-I)- and VIP-induced lactotroph proliferation. These facts led us to investigate the intracellular mechanisms involved in IGF-I- and VIP-induced lactotroph proliferation. Exposure of cultured male rat pituitary cells to IGF-I (10−7 M) or VIP (10−7 M) stimulated the MAPK cascade. Studies in GH4C1 cells, with an expression vector for Rap1 GTPase-activating protein (Rap1 GAP1), demonstrated reduced VIP-induced MAPK activation, indicating that VIP-dependent activation of the extracellular signal-regulated kinase (ERK) pathway requires PKA-Rap1 signaling. IGF-I induced cAMP-response element (CRE)-binding protein (CREB) phosphorylation through the Ras-MAPK pathway, whereas VIP phosphorylated CREB directly via PKA. The mechanisms that regulate IGF-I-and VIP-CREB-dependent gene transcription were examined using GH4C1 cells transiently transfected with a CRE reporter gene. IGF-I and VIP stimulation of CRE-mediated transcription required activation of both Ras-MAPK and cAMP/PKA signaling. This activation was blocked in the presence of Rap1 GAP1. In summary, we showed that IGF-I and VIP stimulated MAPK activity and the phosphorylation of CREB in pituitary cells. Furthermore, VIP-dependent activation of PKA-Rap1-ERK pathways mediated VIP and IGF-I effects on CREB-dependent transcription in GH4C1 cells. Thus, it is possible that VIP- and IGF-I-induced lactotroph proliferation may involve Rap1.
Hexose-6-phosphate dehydrogenase confers oxo-reductase activity upon 11β-hydroxysteroid dehydrogenase type 1
Authors: Bujalska Iwona J , Draper Nicole , Michailidou Zoi , Tomlinson Jeremy W , White Perrin C , Chapman Karen E , Walker Elizabeth A , Stewart Paul M
Published: June 2005

Two isozymes of 11β-hydroxysteroid dehydrogenase (11β-HSD) interconvert active cortisol and inactive cortisone. 11β-HSD2 (renal) acts only as a dehydrogenase, converting cortisol to cortisone. 11β-HSD1 (liver) is a bi-directional enzyme in cell homogenates, whereas in intact cells it typically displays oxo-reductase activity, generating cortisol from cortisone. We recently established that cortisone reductase deficiency is a digenic disease requiring mutations in both the gene encoding 11β-HSD1 and in the gene for a novel enzyme located within the lumen of the endoplasmic reticulum (ER), hexose-6-phosphate dehydrogenase (H6PDH). This latter enzyme generates NADPH, the co-factor required for oxo-reductase activity. Therefore, we hypothesized that H6PDH expression may be an important determinant of 11β-HSD1 oxo-reductase activity. Transient transfection of chinese hamster ovary (CHO) cells with 11β-HSD1 resulted in the appearance of both oxo-reductase and dehydrogenase activities in intact cells. Co-transfection of 11β-HSD1 with H6PDH increased oxo-reductase activity whilst virtually eliminating dehydrogenase activity. In contrast, H6PDH had no effect on reaction direction of 11β-HSD2, nor did the cytosolic enzyme, glucose-6-phosphate dehydrogenase (G6PD) affect 11β-HSD1 oxo-reductase activity. Conversely in HEK 293 cells stably transfected with 11β-HSD1 cDNA, transfection of an H6PDH siRNA reduced 11β-HSD1 oxo-reductase activity whilst simultaneously increasing 11β-HSD1 dehydrogenase activity. In human omental preadipocytes obtained from 15 females of variable body mass index (BMI), H6PDH mRNA levels positively correlated with 11β-HSD1 oxo-reductase activity, independent of 11β-HSD1 mRNA levels. H6PDH expression increased 5.3-fold across adipocyte differentiation (P<0.05) and was associated with a switch from 11β-HSD1 dehydrogenase to oxo-reductase activity. In conclusion, H6PDH is a crucial determinant of 11β-HSD1 oxo-reductase activity in intact cells. Through its interaction with 11β-HSD1, H6PDH may represent a novel target in the pathogenesis and treatment of obesity.
Intra-domain communication between the N-terminal and DNA-binding domains of the androgen receptor: modulation of androgen response element DNA binding
Authors: Brodie Jacqueline , McEwan Iain J
Published: June 2005

The androgen receptor (AR) is a ligand-activated transcription factor that recognises and binds to specific DNA response elements upon activation by the steroids testosterone or dihydrotestosterone. In vitro, two types of response element have been characterised - non-selective elements that bind the androgen, glucocorticoid and progesterone receptors, and androgen receptor-selective sequences. In the present study, the allosteric effects of DNA binding on the receptor amino-terminal domain (NTD) were studied. Binding to both types of DNA response element resulted in changes in the intrinsic fluorescence emission spectrum for four tryptophan residues within the AR-NTD and resulted in a more protease-resistant conformation. In binding experiments, it was observed that the presence of the AR-NTD reduced the affinity of receptor polypeptides for binding to both selective and non-selective DNA elements derived from the probasin, PEM and prostatin C3 genes respectively, without significantly altering the protein–base pair contacts. Taken together, these results highlight the role of intra-domain communications between the AR-NTD and the DNA binding domain in receptor structure and function.
Pharmacogenetic analysis of human steroid 5α reductase type II: comparison of finasteride and dutasteride
Authors: Makridakis Nick , Reichardt Juergen K V
Published: June 2005

Human steroid 5α-reductase type II is a prostate-specific, membrane-associated enzyme that catalyzes the conversion of testosterone to dihydrotestosterone, the most potent androgen in the prostate gland. Genetic variants of this enzyme have been associated with both the development and the progression of prostate cancer. Both finasteride and dutasteride are competitive inhibitors of the type II steroid 5α-reductase that have been effectively used for the treatment of benign prostatic hyperplasia. Finasteride has also been successfully utilized for prostate cancer chemoprevention. We here investigate 5α-reductase inhibition assays in vitro to measure the effect of incubation time on the apparent inhibition constant (Ki) for both constitutional and somatic (prostate cancer) enzyme variants. Our systematic pharmacogenetic analysis shows that both finasteride and dutasteride are slow, time-dependent inhibitors of steroid 5α-reductase type II, and that the inhibition kinetics depend on the 5α-reductase genotype. We also show that, overall, dutasteride is a more efficient steroid 5α-reductase inhibitor than finasteride. Based on our data, we are able to map areas of the enzyme that are responsible for this time-dependent inhibition for either (or both) enzyme inhibitor(s). This comprehensive pharmacogenetic analysis of steroid 5α-reductase variants unveiled significant pharmacogenetic variation for both finasteride and dutasteride and thus should be taken into account when designing protocols for treatment and/or chemoprevention of prostatic diseases with either one of these 5α-reductase inhibitors since there is considerable pharmacogenetic variation for both drugs.
The secretin G-protein-coupled receptor family: teleost receptors
Authors: Cardoso J C R , Clark M S , Viera F A , Bridge P D , Gilles A , Power D M
Published: June 2005

Twenty-one members of the secretin family (family 2) of G-protein-coupled receptors (GPCRs) were identified via directed cloning and data-mining of the Fugu Genome Consortium database, representing the most comprehensive description of secretin GPCRs in a teleost fish to date. Duplicated genes were identified for many of the family members, namely the receptors for pituitary adenylate cyclase-activating polypeptide (PACAP)/vasoactive intestinal peptide (VIP), calcitonin, calcitonin gene-related peptide (CGRP), growth hormone releasing hormone (GHRH), glucagon receptor/glucagon-like peptide (GLP) and parathyroid hormone-related peptide (PTHrP)/PTH. Mining of other teleost genomes (zebrafish and Tetraodon) revealed that the duplicated genes identified in the Takifugu genome were also present in these fish. Additional database searching of the Escherichia coli, yeast, Drosophila, Caenorhabditis elegans and Ciona genomes revealed that the family 2 of GPCRs were only present in the multicellular organisms. Orthologues of all the human secretin receptors were identified with the exception of secretin itself. Additional database searches in the Fugu Genome Consortium database also failed to reveal a secretin ligand and so it is hypothesised that both the receptor and the ligand evolved after the divergence of teleost/tetrapod lineages. Phylogenetic analysis at both the protein and the DNA level provided strong support for each of the individual receptor family groupings, but weak support between groups, making evolutionary inferences difficult. A more critical analysis of the PACAP/VIP receptor family confirmed previous hypotheses that the vasoactive intestinal peptide receptor (VPAC1R) gene is the ancestral form of the receptor.
TRAP220 is modulated by the antineoplastic agent 6-Mercaptopurine, and mediates the activation of the NR4A subgroup of nuclear receptors
Authors: Wansa K D Senali Abayratna , Muscat George E O
Published: June 2005

The NR4A1–3 (Nur77, NURR1 and NOR-1) subfamily of nuclear hormone receptors (NRs) has been implicated in Parkinson’s disease, schizophrenia, manic depression, atherogenesis, Alzheimer’s disease, rheumatoid arthritis, cancer and apoptosis. This has driven investigations into the mechanism of action, and the identification of small molecule regulators, that may provide the platform for pharmaceutical and therapeutic exploitation. Recently, we found that the purine antimetabolite 6-Mercaptopurine (6-MP), which is widely used as an anti-neoplastic and anti-inflammatory drug, modulated the NR4A1–3 subfamily. Interestingly, the agonist-mediated activation did not involve modulation of primary coactivators’ (e.g. p300 and SRC-2/GRIP-1) activity and/or recruitment. However, the role of the subsequently recruited coactivators, for example CARM-1 and TRAP220, in 6-MP-mediated activation of the NR4A1–3 subfamily remains obscure. In this study we demonstrate that 6-MP modulates the activity of the coactivator TRAP220 in a dose-dependent manner. Moreover, we demonstrate that TRAP220 potentiates NOR-1-mediated transactivation, and interacts with the NR4A1–3 subgroup in an AF-1-dependent manner in a cellular context. The region of TRAP220 that mediated 6-MP activation and NR4A interaction was delimited to amino acids 1–800, and operates independently of the critical PKC and PKA phosphorylation sites. Interestingly, TRAP220 expression does not increase the relative induction by 6-MP, however the absolute level of NOR-1-mediated trans-activation is increased. This study demonstrates that 6-MP modulates the activity of the NR4A subgroup, and the coactivator TRAP220.
A haplotype of the CYP27B1 promoter is associated with autoimmune Addison’s disease but not with Graves’ disease in a UK population
Authors: Jennings C E , Owen C J , Wilson V , Pearce S H S
Published: June 2005

Previous studies have suggested an association between alleles of the CYP27B1 (1-α hydroxylase) gene and autoimmune conditions. We have examined three single nucleotide polymorphisms (SNPs) that are located in the 5′ region and promoter of the CYP27B1 gene for association in a cohort of Graves’ disease and autoimmune Addison’s disease subjects from the UK. Genomic DNA samples from white patients with autoimmune Addison’s disease (n=104) and healthy controls (n=464) were genotyped by PCR-RFLP analysis for the SNPs at positions −1260 and −1077 5′ of the coding CYP27B1 sequences. The −1260 SNP was also examined in a cohort of patients with Graves’ disease (n=446). χ2 testing of contingency tables was used to determine the significance of genotypes and alleles. Haplotype frequencies and linkage disequilibrium measures were estimated using the UNPHASED and HAPLOVIEW packages. Alleles at the three CYP27B1 markers were in tight linkage disequilibrium with each other and all showed association with autoimmune Addison’s disease. The maximum evidence for association was with the −1260 C allele (76.0% in Addison’s subjects versus 64.9% in controls; P=0.003; odds ratio 1.71 (5–95% confidence intervals, 1.20–2.44). A global test of significance for the common −1918 T, −1260 C and −1077 G haplotype was significant in Addison’s subjects compared with controls (P=0.01). In contrast, there was no association of alleles at the −1260 SNP with Graves’ disease. We are able to confirm that a CYP27B1 promoter allele is associated with autoimmune Addison’s disease, and extend this finding to include an associated promoter haplotype.
Gene expression profiling of bovine endometrium during the oestrous cycle: detection of molecular pathways involved in functional changes
Authors: Bauersachs S , Ulbrich S E , Gross K , Schmidt S E M , Meyer H H D , Einspanier R , Wenigerkind H , Vermehren M , Blum H , Sinowatz F , Wolf E
Published: June 2005

The endometrium plays a central role among the reproductive tissues in the context of early embryo–maternal communication and pregnancy. It undergoes typical changes during the sexual/oestrous cycle, which are regulated by the ovarian hormones progesterone and oestrogen. To identify the underlying molecular mechanisms we have performed the first holistic screen of transcriptome changes in bovine intercaruncular endometrium at two stages of the cycle – end of day 0 (late oestrus, low progesterone) and day 12 (dioestrus, high progesterone). A combination of subtracted cDNA libraries and cDNA array hybridisation revealed 133 genes showing at least a 2-fold change of their mRNA abundance, 65 with higher levels at oestrus and 68 at dioestrus. Interestingly, genes were identified which showed differential expression between different uterine sections as well. The most prominent example was the UTMP (uterine milk protein) mRNA, which was markedly upregulated in the cranial part of the ipsilateral uterine horn at oestrus. A Gene Ontology classification of the genes with known function characterised the oestrus time by elevated expression of genes, for example related to cell adhesion, cell motility and extracellular matrix and the dioestrus time by higher expression of mRNAs encoding for a variety of enzymes and transport proteins, in particular ion channels. Searching in pathway databases and literature data-mining revealed physiological processes and signalling cascades, e.g. the transforming growth factor-β signalling pathway and retinoic acid signalling, which are potentially involved in the regulation of changes of the endometrium during the oestrous cycle.
The Role of Acceptance and Mindfulness in the Treatment of Insomnia
Authors: Lundh Lars-Gunnar
Published: June 2005

The present article explores possible reasons why acceptance and mindfulness techniques may be beneficial in the treatment of insomnia. First, it is argued that sleep is facilitated by cognitive deactivation, with less controlled information processing as compared with daytime functioning, and correspondingly more acceptance of spontaneously occurring physiological and mental processes. Second, it is argued that mindfulness practice, in the form of nonjudgmental observation of spontaneously occurring physical and psychological processes, may be an effective way of training the skills of cognitive deactivation. As a complement, psychoeducational methods are advocated to help the client develop a more functional schematic model of sleep and sleeplessness.
Candidate Cognitive Processes in Psychophysiologic Insomnia
Authors: Broomfield Niall M. , Gumley Andrew I , Espie Colin A.
Published: June 2005

In this review, we begin by highlighting the lack of available evidence to support current diagnostic criteria for psychophysiologic insomnia. We then outline 3 new testable candidate cognitive processes in psychophysiologic insomnia: attention bias, sleep effort, and metacognitive beliefs. Each candidate element is carefully described. Evidence of involvement in insomnia maintenance is discussed based on the existing literature. The need for an experimental research agenda to examine the interplay of these candidate cognitive processes is then emphasized. Research ideas are presented throughout our discussions.
Assessing Nurses’ Hand Hygiene Practices by Direct Observation or Self-Report
Authors: Larson Elaine L. , Aiello Allison E. , Cimiotti Jeannie P.
Published: June 2005

Methods of obtaining data on hand hygiene practices have not been well validated. The purpose of this study was to compare two methods of assessment of hand hygiene practices—direct observation and self-report using diaries. For 22 months, nursing staff (n= 119) from two neonatal ICUs recorded their hand hygiene practices on a diary card one shift/month (n= 1,071 diary cards). The same data were collected in monthly 1-hour direct observation sessions (n= 206 hours). Amount of time in gloves and total hand hygiene episodes/hour did not differ significantly by diary or observation, but four other specific parameters were significantly different. If hand hygiene practices are to be assessed over time, the same method must be used. Given these measurement limitations, more valid, practical, and less costly methods are needed.
Tobacco Control in the 21st Century: A Critical Issue for the Nursing Profession
Authors: Sarna Linda , Bialous Stella
Published: June 2005

Tobacco control is central to reducing death and disability and improving quality of life worldwide and nursing action is imperative. This article addresses tobacco as a global health issue with implications for nursing practice, education, research, and policy development. The lack of knowledge and skills, lack of expectation for clinical intervention, limited research, an absence of professional policies, and minimal nursing leadership have diminished the critical role that nurses can play in confronting this epidemic. Swift action is needed to ensure that all nurses are prepared to effectively engage in activities to prevent tobacco use, provide evidence-based cessation interventions, and support efforts to prevent exposure to secondhand smoke. Increased opportunities are needed to support creative nursing research efforts that test interventions and strategies to reduce barriers to tobacco control within different cultures, subcultures, and countries.
Ethnic Differences in Predictors of Hearing Protection Behavior Between Black and White Workers
Authors: Hong OiSaeng , Lusk Sally L. , Ronis David L.
Published: June 2005

The purpose of the study is to determine whether there are ethnic differences in predictors of hearing protection behavior between Black and White workers. The Predictors of Use of Hearing Protection Model (PUHPM) derived from Pender’s Health Promotion Model (Pender, 1987) was used as a conceptual model. A total of 2,119 (297 Blacks, 1,822 Whites) were included in the analysis. Internal consistency of instrument items was assessed using theta reliability estimates. Significant predictors of the use of hearing protective devices (HPDs) for Black and White workers and differences in predictors between the two groups were examined using multiple regression with interaction terms. Ethnic differences in scale or individual item scores were assessed using chi-square and t-test analyses. Different factors influenced hearing protection behavior among Black and White workers. The model was much less predictive of Blacks’ hearing protection behavior than Whites’ (R2 = .12 vs. .36). Since the PUHPM was not as effective in predicting hearing protection behavior for Blacks as for Whites, future studies are needed to expand the PUHPM through qualitative study and to develop culturally appropriate models to identify factors that better predict hearing protection behavior as a basis for developing effective interventions.
Self-Destructive and Delinquent Behaviors of Adolescent Female Victims of Child Sexual Abuse: Rates and Covariates in Clinical and Nonclinical Samples
Authors: Wright John , Friedrich William , Cinq-Mars Caroline , Cyr Mireille , McDuff Pierre
Published: June 2005

Self-destructive and delinquent behaviors were assessed in three samples of adolescent females. The first sample (N = 140) were substantiated victims of sexual abuse recruited from clinical settings. They were contrasted to a second sample (N = 430) of secondary school students, and a third sample from the same school setting (N = 94), that reported that they had been sexually abused. Few differences were found between the two groups of sexually abused girls, and both groups reported significantly more at-risk behaviors than nonabused girls. Family adversity was a consistent predictor of both self-destructive and delinquent behaviors. However, violence during the abuse, lower quality mother-daughter relationships, and depression were also related to self-destructive behaviors, while family economic problems and self-blame for the abuse were the only correlates of delinquent behavior.
Impact of Interaction With a Partner or Friend on the Exposure Effects of Pornography and Erotica
Authors: Senn Charlene Y. , Desmarais Serge
Published: June 2005

Past studies on the effects of sexually explicit materials on women have tended to study them alone, in pairs, or in groups of strangers. By contrast, our study randomly assigned women to bring either a same-sex friend or a male partner to reflect more natural viewing conditions. Discussion between the participant and her companion followed exposure to the sexual images. Women who viewed pornography maintained their (quite high) level of negative mood, whereas women who viewed erotica experienced a substantial improvement in mood. The sex of the companion did not have a direct influence on participants’ mood, with discussion improving mood across the board. However, participants’ ratings of their satisfaction with the discussion were significantly influenced by the sex of their companion. We suggest that future research should focus more on the interpersonal aspects of male-female relationships when exploring the effects of sexually explicit materials on heterosexual women.
Association Between Overt and Relational Aggression and Psychosocial Adjustment in Undergraduate College Students
Authors: Storch Eric A. , Bagner Daniel M. , Geffken Gary R. , Baumeister Audrey L.
Published: June 2005

This study examined the relations between overt and relational aggression, social anxiety, loneliness, depressive symptoms, and alcohol and drug use in a sample of 287 undergraduate college students. Consistent with prior work, men reported engaging in more overt aggression than women. Contrary to our predictions, men also reported engaging in more relational aggression than women. Results also indicated that overt and relational aggression were positively associated with social anxiety, loneliness, depressive symptoms, alcohol use, and drug use for the overall sample. Hierarchical regression analyses showed positive relations between overt aggression and alcohol use for men and no relations between relational aggression and any psychosocial adjustment index. For women, overt aggression uniquely predicted social anxiety, loneliness, and depressive symptoms, whereas relational aggression uniquely predicted social anxiety, loneliness, depression, and alcohol and drug problems. Implications of these findings are discussed in terms of the role of peer aggression in students’ psychosocial adjustment.
Effects of water hardness on toxicological responses to chronic waterborne silver exposure in early life stages of rainbow trout (Oncorhynchus mykiss)
Authors: Morgan Tammie P. , Guadagnolo Christine M. , Grosell Martin , Wood Chris M.
Published: June 2005

Rainbow trout embryos and larvae were exposed to 0, 0.1, and 1 μg/L total silver (as AgNO3) in water of three different hardnesses (soft water [2 mg/L as CaCO3], moderately hard water [150 mg/L], and hard water [400 mg/L]) in a flow-through system from fertilization to swim-up (64 d). The objective of the study was to investigate the effects of water hardness on chronic silver toxicity. In the absence of silver, elevating hardness had a positive effect on early life stage survival and development, significantly decreasing mortality and accelerating time to 50% swim-up. Following hatch, exposure to 1 μg/L Ag significantly increased mortality relative to exposure to 0 μg/L Ag. No significant effects of silver on time to 50% hatch were observed; however, time to 50% swim-up was delayed, and 50% swim-up was not achieved over the course of the experiment during some exposures to 1 μg/L Ag. These results suggest that the current Canadian Water Quality Guideline (http://www.ccme.ca/assets/pdf/el_062.pdf) of 0.1 μg/L Ag is sufficient in preventing mortality and altered development in early life stages of rainbow trout. Increasing water hardness from 2 to 150 or 400 mg/L was modestly protective against the mortality and delays in time to 50% swim-up associated with exposure to 1 μg/L Ag. The 150- and 400-mg/L hardnesses were equally protective against mortality, but 150-mg/L was more protective than 400-mg/L hardness against the delays in time to 50% swim-up. Overall, the protective effects of hardness on chronic silver toxicity in early life stages of rainbow trout are modest but similar to the protection afforded to acute silver toxicity in juvenile and adult rainbow trout.
Effects of lambda-cyhalothrln in two ditch microcosm systems of different trophic status
Authors: Roessink Ivo , Arts Gertie H.P. , Belgers J. Dick M. , Bransen Fred , Maund Steve J. , Brock Theo C.M.
Published: June 2005

The fate and effects of the pyrethroid insecticide lambda-cyhalothrin were compared in mesotrophic (macrophyte-dominated) and eutrophic (phytoplankton-dominated) ditch microcosms (∼0.5 m3). Lambda-cyhalothrin was applied three times at one-week intervals at concentrations of 10, 25, 50, 100, and 250 ng/L. The rate of dissipation of lambda-cyhalothrin in the water column of the two types of test systems was similar. After 1 d, only 30% of the amount applied remained in the water phase. Initial, direct effects were observed primarily on arthropod taxa. The most sensitive species was the phantom midge (Chaoborus obscuripes). Threshold levels for slight and transient direct toxic effects were similar (10 ng/L) between types of test systems. At treatment levels of 25 ng/L and higher, apparent population and community responses occurred. At treatments of 100 and 250 ng/L, the rate of recovery of the macroinvertebrate community was lower in the macrophyte-dominated systems, primarily because of a prolonged decline of the amphipod Gammarus pulex. This species occurred at high densities only in the macrophyte-dominated enclosures. Indirect effects (e.g., increase of rotifers and microcrustaceans) were more pronounced in the plankton-dominated test systems, particularly at treatment levels of 25 ng/L and higher.
Fish critical cellular residues for surfactants and surfactant mixtures
Authors: Bernhard Mary Jo , Dyer Scott D.
Published: June 2005

The feasibility of using in vitro methods to predict in vivo critical body residue (CBR) for single surfactants and mixtures by measuring the critical cell residue (CCR) in a hepatic fish cell line (PLHC-1C) was investigated. The CCR values were determined using radiochemical methods to measure the test compound partitioning between media and cells at varying concentrations for three distinctly different surfactants (anionic, cationic, and nonionic) and their mixture. The cell median effective concentration (EC50) values for hexadecyltrimefhylammonium chloride (C16TMAC), dodecyl hexaethoxylate (C12E6), and sodium dodecylbenzene sulfonate (C12LAS) ranged from 2.9 to 163.3 μM, a 54-fold difference. These cell EC50 values indicate that the cells are several-fold less sensitive to surfactants than whole organisms are. However, based on cellular residue levels for each surfactant and their mixture, only an approximately threefold difference was observed with a range of 0.6 to 1.8 mmol/kg. These concentrations correspond closely to in vivo body burdens (0.2–8 mmol/kg) associated with nonpolar organic or narcosis-acting compounds and their mixtures. The CCRs could provide an alternative and rapid technique to predict CBRs.
Unexpected reduction in reproduction of collembola exposed to an arsenic-contaminated soil
Authors: Crouau Yves , Cazes Laurent
Published: June 2005

To assess the problems posed by ecological testing of the toxicity of polluted soils, we applied the Collembola reproduction test to the soil from a mining site polluted by metals. Our aim was to quantify the chronic toxicity of contaminated soil using the Folsomia Candida reproduction test. Briefly, the polluted soil, which contains in particular large quantities of arsenic, is mixed in various proportions with a reference soil, and the number of juveniles is counted five weeks later. The results were quite unexpected in that a stronger effect was observed on reproduction with dilute contaminated soil, 0.78 to 3.1%, than with much higher concentrations. The pure contaminated soil is not highly toxic. Arsenic (As) dosage in pore water shows that a change in its bioavailability occurs that may explain the surprising toxicity results. As the main contaminant of the soil was arsenic, we showed that the lowest-observed-effect concentration and the median effective concentration of this metal for the reproduction of F. Candida in International Organization for Standardization (Geneva, Switzerland) soil experimentally contaminated with arsenic were low (2.22 and 2.19 μg/g, respectively). Likewise, we showed that pH modifies the bioavailability and the toxicity of As, but we do not think that this parameter explains the test results. These results show that this bioassay should be used cautiously to test toxicity of polluted soils.
Can the choice of endpoint lead to contradictory results of mixture-toxicity experiments?
Authors: Cedergreen Nina , Streibig Jens C.
Published: June 2005

Theoretically, the effect of two independently acting compounds in a mixture will depend on the slope of the dose-response curves of the individual compounds if evaluated in relation to the model of concentration addition (CA). In the present study, we explored development of the shape of the dose-response relationship for four different recommended endpoints (surface area, frond number, fresh weight-specific, and dry weight-specific relative growth rates [RGRA, RGRF, RGRFW, and RGRDW, respectively]) and for two differently acting herbicides (metsulfuron-methyl and terbuthylazine) over time (3–15 d) on the standard test plant Lemna minor to identify endpoints and experiment times for which predictions of independent action (IA) would depart the most from those of CA. After a test time of 6 d, predictions of IA based on RGRA and RGRFW showed antagonism in relation to CA. Based on RGRDW, synergy was predicted, whereas IA based on RGRF was indistinguishable from CA. To test the prediction of choice of endpoint giving different results in mixture-toxicity experiments, three endpoints and six combinations of independently acting herbicides were evaluated using isobolograms. The experiments showed that in four of six herbicide combinations, different conclusions were reached depending on endpoint. The contradictory isoboles did not follow the theory of IA and, therefore, are more likely to be related to differences in susceptibility of the physiological processes affecting each endpoint than to the shape of the dose-response curve.
Identification of chlorfenvinphos toxicity in a municipal effluent in Sydney, New South Wales, Australia
Authors: Bailey Howard C. , Elphick James R. , Krassoi Rick , Mulhall Ann-Marie , Lovell Adam J. , Slee Daniel J.
Published: June 2005

Acute toxicity in a municipal sewage treatment plant in Sydney, New South Wales, Australia, was traced to chlorfenvinphos, an organophosphorous pesticide. Toxicity identification evaluation procedures led to the tentative identification of chlorfenvinphos as the toxic contaminant in the sample. Subsequent analytical verification revealed 0.95 μg/L of chlorfenvinphos in the effluent sample, and spiking studies confirmed that it accounted for the observed toxicity. The 48-h median lethal concentration of chlorfenvinphos to Ceriodaphnia dubia averaged 0.28 μg/L (n = 4). Source-control measures were effective at eliminating chlorfenvinphos and associated toxicity from the discharge.
Vapor pressure of ten polychlorinated biphenyl congeners and two commercial fluids as a function of temperature
Authors: Nakajoh Katsuhiko , Shibata Etsuro , Todoroki Tomohiro , Ohara Atsushi , Nishizawa Katsushi , Nakamura Takashi
Published: June 2005

The Knudsen mass-loss effusion technique was used to measure the vapor pressures of commercial Kanechlor fluids (Kanechlor 300 and Kanechlor 500) and 10 major individual polychlorinated biphenyls (PCBs) in Kanechlors as a function of temperature and ortho-chlorine substitution. From the temperature dependence of vapor pressure, the thermodynamic parameters, such as enthalpies and entropies of sublimation and vaporization, were derived using the Clausius-Clapeyron equation. The results were compared with both experimental and calculated literature values. The ortho-chlorine substitution effects on the vapor pressure of major PCB congeners in Kanechlor mixtures were studied on the same homologous series. Within this series, the greater the number of chlorine substitutions in the ortho-positions, the higher the vapor pressure, because of the ortho-effect.
Reduction and methylation of mercury in the terrestrial isopod Porcellio scaber (Crustacea) and its environment
Authors: Nolde Natasa , Drobne Damjana , Horvat Milena , Jereb Vesna
Published: June 2005

Reduction and methylation of inorganic mercury in Porcellio scaber (Isopoda, Crustacea) and its environment were studied, using a purpose-built experimental setup where Hg cycling was followed using 203Hg2+ tracer in experiments without and with isopods. In experiment without isopods, daily reduction of 203Hg2+ to 203Hg0 under sterile and nonsterile conditions was measured for three weeks to assess the contribution of bacteria to this process. In experiments with isopods, daily release of 203Hg0 was measured for two weeks. Total mercury (T203Hg) and monomethylmercury (Me203Hg) in whole animals, gut, digestive glands (hepatopancreas), food (hazelnut leaves), and feces were measured to obtain the assimilation and distribution of mercury in the animals, to investigate the origin and fate of Me203Hg, and, finally, to assess the mass balance of mercury in the experimental system. Experiment without isopods showed the important role of bacteria in reduction of 203Hg2+ to 203Hg0, especially in the first day of the experiment. Experiments with isopods showed that formation of 203Hg0 depended on the 203Hg2+ concentration in the food. The contribution of the isopod's digestive flora in reduction of 203Hg2+ to 203Hg0 was negligible. Approximately 3% of T203Hg and 2% of Me203Hg consumed was assimilated by the animals. Methylation of 203Hg2+ occurred already in the leaves before they were consumed by the isopods. Assimilation of Me203Hg from the food surprisingly was low. Also, a loss of Me203Hg was noticed when comparing assimilated and excreted Me203Hg versus consumed Me203Hg. This may be explained by the assumption that demethylation of MeHg prevailed over methylation of Hg2+in the animal's digestive system, leading to excretion of ingested mercury as Hg2+.
Synergistic effects of esfenvalerate and infectious hematopoietic necrosis virus on juvenile chinook salmon mortality
Authors: Clifford Mark A. , Eder Kai J. , Werner Ingeborg , Hedrick Ronald P.
Published: June 2005

Sublethal concentrations of pollutants may compromise fish, resulting in increased susceptibility to endemic pathogens. To test this hypothesis, juvenile chinook salmon (Oncorhynchus tshawytscha) were exposed to sublethal levels of esfenvalerate or chlorpyrifos either alone or concurrently with infectious hematopoietic necrosis virus (IHNV). Three trials were performed with fish exposed to concentrations of IHNV between 0.8 × 102 and 2.7 × 106 plaque-forming units/ml and to 5.0 μg/L of chlorpyrifos or 0.1 μg/L of esfenvalerate. The presence and concentration of IHNV in dead fish were assayed by virus isolation and plaque assay techniques, respectively. Among groups exposed to both esfenvalerate and IHNV, 83% experienced highly significant (p < 0.001) mortality, ranging from 20 to 90% at 3 d post-virus exposure, and cumulatively died from 2.4 to 7.7 d sooner than fish exposed to IHNV alone. This trend was not seen in any other treatment group. Virus assays of dead fish indicate a lethal synergism of esfenvalerate and IHNV. Chlorpyrifos had no observed effect on total mortality or IHNV susceptibility. The present results suggest that accepted levels of pollutants may be seemingly nonlethal to fish but, in fact, be acting synergistically with endemic pathogens to compromise survivorship of wild fish populations through immunologic or physiologic disruption.
Influence of water chemistry on the acute toxicity of copper and zinc to the cladoceran Ceriodaphnia cf dubia
Authors: Hyne Ross V. , Pablo Fleur , Julli Moreno , Markich Scott J.
Published: June 2005

This study determined the influence of key water chemistry parameters (pH, alkalinity, dissolved organic carbon [DOC], and hardness) on the aqueous speciation of copper and zinc and its relationship to the acute toxicity of these metals to the cladoceran Ceriodaphnia cf dubia. Immobilization tests were performed for 48-h in synthetic or natural waters buffered at various pH values from 5.5 to 8.4 (other chemical parameters held constant). The toxicity of copper to C. cf dubia decreased fivefold with increasing pH, whereas the toxicity of zinc increased fivefold with increasing pH. The effect of DOC on copper and zinc toxicity to C. cf dubia was determined using natural fulvic acid in the synthetic water. Increasing DOC was found to decrease linearly the toxicity of copper, with the mean effect concentration of copper that immobilized 50% of the cladocerans (EC50) value 45 times higher at 10 mg/L, relative to 0.1 mg/L DOC at pH 6.5. In contrast, the addition of 10 mg/L DOC only resulted in a very small (1.3-fold) reduction in the toxicity of zinc to C. cf dubia. Copper toxicity to C. cf dubia generally did not vary as a function of hardness, whereas zinc toxicity was reduced by a factor of only two, with an increase in water hardness from 44 to 374 mg CaCO3/L. Increasing bicarbonate alkalinity of synthetic waters (30–125 mg/L as CaCO3) decreased the toxicity of copper up to fivefold, which mainly could be attributed to the formation of copper-carbonate complexes, in addition to a pH effect. The toxicity of copper added to a range of natural waters with varying DOC content, pH, and hardness was consistent with the toxicity predicted using the data obtained from the synthetic waters.