bluuebunny/crossref_metadata_2025 huggingface dataset:
Television and Adolescent Use of Over-the-Counter Analgesic Agents
Authors: Van den Bulck Jan , Leemans Lies , Laekeman Gert M
Published: November 2004

BACKGROUND:

Portrayals of the use of over-the-counter (OTC) analgesics on television may stimulate their use.

OBJECTIVE:

To explore the association between taking OTC analgesics and television viewing by adolescents.

METHODS:

A standardized self-administered questionnaire among first-year (mean age 13.16 y) and fourth-year (mean age 16.37 y) secondary students in Flanders, Belgium (n = 2546) was administered in a school setting. The independent variable was television viewing; control variables were school year, gender, drinking alcohol, days off sick, computer gaming, and Internet use. The main outcome variable was monthly use of OTC analgesics.

RESULTS:

On average, respondents watched 3 hours 18 minutes of television per day (boys more than girls, first-year students more than fourth-year students). Per additional hour of television per day, the odds that respondents were regular users of analgesics were 1.16 times higher (95% CI 1.08 to 1.24). For the 10% heaviest viewers, the odds were 2.30 times higher (95% CI 1.25 to 4.24) compared with the 10% lightest viewers. Odds of OTC analgesic use were higher for students reporting more sick days in the past year (OR 1.38, 95% CI 1.28 to 1.49), regular users of alcohol (OR 1.33, 95% CI 1.17 to 1.50), and girls (OR 1.92, 95% CI 1.35 to 2.73).

CONCLUSIONS:

A relationship was found between watching television and the use of OTC analgesics, even after controlling for gender and lifestyle measures. More research is needed to establish whether this relationship is causal.
Adverse Reactions During Imatinib and Lansoprazole Treatment in Gastrointestinal Stromal Tumors
Authors: Severino Giovanni , Chillotti Caterina , De Lisa Roberto , Zompo Maria Del , Ardau Raffaella
Published: November 2004

OBJECTIVE:

To report the case of a patient affected by gastrointestinal stromal tumors (GIST) who developed cutaneous adverse drug reactions during treatment with imatinib and lansoprazole.

CASE SUMMARY:

After 2 months of treatment with imatinib 400 mg/day, a 60-year-old white female affected by GIST developed bilateral palpebral edema with hyperemic conjunctivae and labial edema when lansoprazole 15 mg/day was introduced to treat dyspeptic symptomatology. Treatment was discontinued, and on reintroduction of both drugs, the patient developed Stevens—Johnson syndrome. Two months later, generalized cutaneous reactions appeared immediately following reintroduction of low-dose imatinib with corticosteroid plus lansoprazole treatment. After discontinuation of all drugs, with the exception of the corticosteroid, the progression of cutaneous lesions stopped.

DISCUSSION:

The use of imatinib is commonly associated with a high dose-dependent rate of rash and edema. Several cases of Stevens—Johnson syndrome have also been described, although not in patients affected by GIST. Severe skin reactions have been reported for lansoprazole including erythema multiforme, Stevens—Johnson syndrome, and toxic epidermal necrolysis. Applying Naranjo's algorithm, the adverse events were considered possible due to imatinib and probable due to lansoprazole.

CONCLUSIONS:

On the basis of the data reported, we conclude that the adverse reactions described may be attributed to either drug alone. However, combined use of drugs may increase the risk of onset of these adverse reactions due to a potential drug interaction involving CYP3A4.
Short- and Long-Term Effects of Cholinergic Modulation on Gamma Oscillations and Response Synchronization in the Visual Cortex
Authors: Rodriguez Rosa , Kallenbach Ulrich , Singer Wolf , Munk Matthias H. J.
Published: November 2004

Neurons can engage in synchronized oscillatory activity in the gamma-frequency range when responding to sensory stimuli. Both the oscillatory patterning and the synchronization of responses are enhanced with arousal and attention or when the electroencephalogram is activated by electrical stimulation of the mesencephalic reticular formation. Here we show with intracortical application of cholinergic antagonists that the enhancement of gamma oscillations and response synchronization is mediated by acetylcholine and muscarinic receptors. We demonstrate further that coapplication of cholinergic agonists with synchrony-inducing light stimuli causes a lasting increase in the probability that the stimulated cells engage in gamma oscillations and response synchronization. These changes develop slowly over tens of minutes and then persist for many hours. Thus, cholinergic modulation plays a crucial role both in the fast, state-dependent facilitation of gamma oscillations and response synchronization and in use-dependent long-term modifications of cortical dynamics that favor synchronization of responses in the gamma-frequency range.
Molecular Mechanism of Pregnenolone Sulfate Action at NR1/NR2B Receptors
Authors: Horak Martin , Vlcek Kamil , Petrovic Milos , Chodounska Hana , Vyklicky Ladislav
Published: November 2004

NMDA receptors are highly expressed in the CNS and are involved in excitatory synaptic transmission and synaptic plasticity as well as excitotoxicity. They have several binding sites for allosteric modulators, including neurosteroids, endogenous compounds synthesized by the nervous tissue and expected to act locally. Whole-cell patch-clamp recording from human embryonic kidney 293 cells expressing NR1-1a/NR2B receptors revealed that neurosteroid pregnenolone sulfate (PS) (300 μm), when applied to resting NMDA receptors, potentiates the amplitude of subsequent responses to 1 mmglutamate fivefold and slows their deactivation twofold. The same concentration of PS, when applied during NMDA receptor activation by 1 mmglutamate, has only a small effect. The association and dissociation rate constants of PS binding and unbinding from resting NMDA receptors are estimated to be 3.3 ± 2.0 mm-1sec-1and 0.12 ± 0.02 sec-1, respectively, corresponding to an apparent affinityKdof 37 μm. The results of experiments indicate that the molecular mechanism of PS potentiation of NMDA receptor responses is attributable to an increase in the peak channel open probability (Po). Responses to glutamate recorded in the continuous presence of PS exhibit marked time-dependent decline. Our results indicate that the decline is induced by a change of the NMDA receptor affinity for PS after receptor activation.

These results suggest that the PS is a modulator of NMDA receptorPo, the effectiveness of which is lowered by glutamate binding. This modulation may have important consequences for the neuronal excitability.
Nitric Oxide Synthase (NOS)-Interacting Protein Interacts with Neuronal NOS and Regulates Its Distribution and Activity
Authors: Dreyer Jacqueline , Schleicher Michael , Tappe Anke , Schilling Kirstin , Kuner Thomas , Kusumawidijaja Grace , Müller-Esterl Werner , Oess Stefanie , Kuner Rohini
Published: November 2004

Mechanisms governing the activity of neuronal nitric oxide synthase (nNOS), the major source of nitric oxide (NO) in the nervous system, are not completely understood. We report here a protein-protein interaction between nNOS and NOSIP (nitric oxide synthase-interacting protein) in rat brainin vivo. NOSIP and nNOS are concentrated in neuronal synapses and demonstrate significant colocalization in various regions of the central and peripheral nervous systems. NOSIP produces a significant reduction in nNOS activity in a neuroepithelioma cell line stably expressing nNOS. Furthermore, overexpression of NOSIP in cultured primary neurons reduces the availability of nNOS in terminal dendrites. These results thus suggest that the interaction between NOSIP and nNOS is functionally involved in endogenous mechanisms regulating NO synthesis. Furthermore, we found that the subcellular distribution and expression levels of NOSIP are dynamically regulated by neuronal activityin vitroas well asin vivo, suggesting that NOSIP may contribute to a mechanism via which neuronal activity regulates the synaptic availability and activity of nNOS.
Chemotherapy for the Brain: The Antitumor Antibiotic Mithramycin Prolongs Survival in a Mouse Model of Huntington's Disease
Authors: Ferrante Robert J. , Ryu Hoon , Kubilus James K. , D'Mello Santosh , Sugars Katharine L. , Lee Junghee , Lu Peiyuan , Smith Karen , Browne Susan , Beal M. Flint , Kristal Bruce S. , Stavrovskaya Irina G. , Hewett Sandra , Rubinsztein David C. , Langley Brett , Ratan Rajiv R.
Published: November 2004

Huntington's disease (HD) is a fully penetrant autosomal-dominant inherited neurological disorder caused by expanded CAG repeats in the Huntingtin gene. Transcriptional dysfunction, excitotoxicity, and oxidative stress have all been proposed to play important roles in the pathogenesis of HD. This study was designed to explore the therapeutic potential of mithramycin, a clinically approved guanosine-cytosine-rich DNA binding antitumor antibiotic. Pharmacological treatment of a transgenic mouse model of HD (R6/2) with mithramycin extended survival by 29.1%, greater than any single agent reported to date. Increased survival was accompanied by improved motor performance and markedly delayed neuropathological sequelae. To identify the functional mechanism for the salubrious effects of mithramycin, we examined transcriptional dysfunction in R6/2 mice. Consistent with transcriptional repression playing a role in the pathogenesis of HD, we found increased methylation of lysine 9 in histone H3, a well established mechanism of gene silencing. Mithramycin treatment prevented the increase in H3 methylation observed in R6/2 mice, suggesting that the enhanced survival and neuroprotection might be attributable to the alleviation of repressed gene expression vital to neuronal function and survival. Because it is Food and Drug Administration-approved, mithramycin is a promising drug for the treatment of HD.
Pessimism and the Evolution of Negativity
Authors: Leahy Robert L.
Published: November 2004

The universal and nonrandom distribution of anxiety, fears, and depression suggests that there may have been underlying evolutionary pressures leading to adaptations for pessimistic thinking. Symptoms and processes that today we may label as psychopathology may have solved problems in an evolutionarily relevant environment, providing variations in individual behavior as a response to variations in availability of resources and vulnerability to threats and danger from predation. For example, investment strategies, the focus of this article, change with seasonal variation. Hibernation is marked by reduction of demand by limiting metabolic rates, activity, and arousal during winter months when resources are reduced, and conservation is salient, whereas manic enthusiasm focuses on short windows of opportunity, emphasizing overvaluation of pleasure, exploration, breeding, and diversification. A general theoretical model of investment strategies is proposed that accounts for sex differences in parental investments. Cognitive schemata focused on pessimistic strategies are viewed as operating through evolved algorithms that attempt to assure that behavioral and genetic investments are protected. These cognitive biases may account for male strategies of diversification and female strategies of consolidation and protection, and suggest possible determinants of a greater likelihood of females to be characterized by inhibition and depression.
Domain Specificity of Gender Differences in Rumination
Authors: Mezulis Amy H. , Abramson Lyn Y. , Hyde Janet S.
Published: November 2004

Rumination, defined as repetitively focusing on the causes, meanings, and symptoms of depressed mood, has been associated with the onset, maintenance, and exacerbation of depression. Although several studies have identified gender differences in rumination, with females being more likely to ruminate than males, no study to date has examined whether gender differences in rumination vary across domains. The current study examined whether females may be more vulnerable to rumination in response to negative events in domains hypothesized to be particularly salient to females, such as interpersonal or body image domains. To this end, 259 undergraduates (148 females, 111 males) completed three different rumination questionnaires, one assessing rumination in response to “sad or depressed mood,” another assessing rumination in response to “stressful events,” and a third assessing rumination in response to a series of negative events in 3 separate domains: achievement, interpersonal, and body image/attractiveness. On all measures, females reported more rumination than males. The effect sizes for gender differences in rumination in response to depressed mood or stressful events, as well as the effect size for gender differences in rumination in response specifically to achievement events, were small. By contrast, effect sizes for gender differences in rumination in response specifically to negative interpersonal and body image events were in the moderate to large range. Results support the hypothesis that although females display an overall greater tendency than males to ruminate in response to negative events and depressed mood, gender differences in rumination may be particularly pronounced in the interpersonal and body image domains.
Testing of the PHS-ES: A Measure of Perimenopausal Health Self-Efficacy
Authors: Reece Susan McClennan , Harkless Gene E.
Published: November 2004

This article summarizes the development and psychometric analysis of the Perimenopausal Health Self-Efficacy Scale (PHS-ES) designed to assess women’s health promotion self-efficacy related to mid-life changes in health. Items were generated from a qualitative study of HRT decision-making and recommended health promotion activities. The PHS-ES was administered 2 weeks apart to 98 university-based women ages 45 to 64 along with the measures of functional health status, stress, and the self-concept. Internal consistency (α = .88 and .90) and test-retest reliabilities (.86) were acceptable. Four factors emerged during factor analysis with 21 of the items explaining 50% of the variance and which were consistent with the conceptual basis of the PHS-ES. The PHS-ES was significantly correlated with functional health status, self-concept, stress, age and body mass index (BMI). In conjunction with stress and BMI, the PHS-ES predicted 50% of the variance of functional health. Further reliability and validity assessments are recommended with more racially and socioeconomically heterogeneous groups of perimenopausal women. It was concluded that the PHS-ES adequately demonstrated reliability and validity in this study.
Correlations Among Measures of Bladder Function and Comfort
Authors: Dowd Thérèse , Kolcaba Katherine , Steiner Richard
Published: November 2004

There is a need for standard functional and psychosocial measurements of compromised urinary bladder syndrome (CUBS). Utilizing Kolcaba’s Comfort Theory, the purpose of this study was to assess the psychometric properties and relationships among 8 measures of comfort, status of urinary frequency and incontinence, and quality of life. A convenience sample of 47 persons (45 women, 2 men) ages 25 to 92, who had UI for more than 6 months, was recruited. Data were collected twice with a 2-week interval. We examined (a) 1 measure of the immediate outcome of comfort related to CUBS, (b) 5 measures of UI status, and (c) 2 measures of quality of life. Reliabilities were adequate for all measures. Relationships among variables are presented and discussed. Recommendations are made for measures that detect improvement over time related to first line interventions.
Stability of Self-Reported Family History of Prostate Cancer Among African American Men
Authors: Weinrich Sally P. , Faison-Smith Louise , Hudson-Priest Julie , Royal Charmaine , Powell Isaac
Published: November 2004

The genome-wide search for the prostate cancer gene holds the promise of the availability of prostate cancer susceptibility testing in the near future. When this occurs, self-reported history of prostate cancer will be critical in determining who is eligible for cancer susceptibility testing. Little attention has been given to the reliability of self-reported family history of prostate cancer, particularly in African American men. This correlational study measured the stability of self-reported family history of prostate cancer over a one-year time period (between 1997 and 1998) with 96 African American men from a southern state. The men were asked on two separate occasions, 1 year apart, “Have any of your men blood relatives ever had prostate cancer?” The question had a prior test-retest reliability of 0.85 over a 2-week period. Forty-eight percent of the men changed their answers on the second administration. Men most likely to change their answers were low-income men and men who did not participate in a free prostate cancer screening. This research highlights the need for public genetic education and the recognition by health professionals that self-reported family history of cancer is a variable that changes as families have increased awareness and communication concerning family history of cancer.
Reliability of Transportable Instruments for Assessment of Infant Length
Authors: Byrne Mary Woods , Lenz Elizabeth R.
Published: November 2004

Transportable instruments for use in home and field settings have been used for decades on the basis of assumed reliability. This article describes a study that compares two portable devices for measuring length, the tape measure and the Measure Mat, against a clinical standard stadiometer with two convenience samples of Hispanic and African-American infants in an urban general pediatrics practice setting. Mean net difference between the stadiometer and the tape measure was 1.68 inches in the first sample and 0.92 inches in the second; the difference between the stadiometer and the Measure Mat was 0.92 inches. The least variability and random error (SD = 0.57 inch) was shown in the paired measurements using the stadiometer and the Measure Mat. Bland-Altman plots showed positive bias for both portable devices across the range of measurements.
Psychometric Characteristics of the Depressive Cognition Scale in African American Women
Authors: Zauszniewski Jaclene A. , Fulton Picot Sandra J. , Debanne Sara M. , Roberts Beverly L. , Wykle May L.
Published: November 2004

Depression in African-American women frequently goes unnoticed and untreated since commonly used depression scales fail to focus on early symptom recognition, do not address contextual factors, and lack adequate psychometric testing in African-American women. This analysis of the Depressive Cognition Scale was conducted with 213 African-American female caregivers and noncaregivers. Alpha coefficients for both groups (α ‘s = .75 and .87) showed internal consistency. Correlations with resourcefulness, depression, and daily hassles scales in the expected directions demonstrated construct validity (R’s = −.36, .26, and .31, respectively). Factor structures for caregivers and noncaregivers differed, suggesting certain depressive cognitions were strongly integrated into the caregiver role. As a reliable and valid measure of depressive cognitions, the DCS would be useful for early detection of depression in African-American women.
Effects of 4-nonylphenol on phytoplankton and periphyton in aquatic microcosms
Authors: Hense Burkhard A. , Jüttner Ingrid , Welzl Gerhard , Severin Gabriele F. , Pfister Gerd , Behechti Akbar , Schramm Karl-Werner
Published: November 2004

The effects of nonylphenol (NP) on phytoplankton and periphyton were studied in 230 L outdoor microcosms. Phytoplankton cell density and biomass, phytoplankton and periphyton diversity, and assemblage composition were analyzed during a four-week preapplication period, followed by six weeks of NP treatment via controlled release and a six weeks postapplication period. Changes in species richness and diversity were not correlated with NP concentrations. However, changes in phytoplankton cell densities during the first week of the postapplication period were related to previous exposure. In the controls and the lowestdosed microcosm, Conjugatophyceae constituted most of the biomass during the dosing and the postapplication period. In contrast, Dinophyceae dominated the biomass during the dosing and the postapplication period at higher NP concentrations. Principal response curves revealed changes in phytoplankton assemblage composition during the dosing and the postapplication period. Dinophyceae and most Cyanophyceae were more abundant at intermediate and higher NP concentrations, whereas Conjugatophyceae were less abundant compared to controls. Assemblages only partly recovered during the postapplication period. Periphyton taxon richness, diversity, and assemblage change was not related to NP concentrations. At the lowest and intermediate concentration, assemblages were significantly different from the controls and the higher concentrations, which were similar during the treatment period.
Lethal and sublethal toxicity of didecyldimethylammonium chloride in early life stages of white sturgeon, Acipenser transmontanus
Authors: Teh Swee Joo , Wong Cecilia , Furtula Vesna , Teh Foo-Ching
Published: November 2004

This study was conducted to describe the acute lethality and latent toxicity of didecyldimethylammonium chloride (DDAC) on early life stages of white sturgeon (Acipenser transmontanus). Fish responses to 0, 10, 50, 100, 250, 500 μg/L concentrations of DDAC were determined using a 96-h standard static renewal method for acute toxicity testing, with three replicates per concentration. Twenty fish per replicate were tested for 3, 11, and 42-d-old larvae, and 7 fish per replicate were tested for 78-d-old juveniles. Following exposure, survival and growth were evaluated in exposed fish raised in clean water for 2 weeks. The 96-h median lethal concentration (LC50) values for DDAC were 10.0 to 50.0, 58.5, and 99.7 μg/L for 3, 11, and 42-d-old larvae and 100 to 250 μg/L for 78-d-old juveniles. Significant decreases in larval growth and survival were noted at all tested concentrations and in all sturgeon age groups. Results of this study reveal age- and concentration-dependent responses to DDAC. Among the age groups tested, the 3-d-old larvae were the most sensitive group. Results also revealed that 96-h lethality testing alone is not adequate for determining the toxicity of DDAC to white sturgeon.
Evaluation of brominated diphenyl ether-99 toxicity with Raphidocelis subcapitata and Daphnia magna
Authors: Evandri Maria Grazia , Costa Lucio Guido , Bolle Paola
Published: November 2004

Bromineted flame ratardants belong ta anew class of environmental contaminants. To obtain new information regarding the effects of 2,2′,4,4′,5-brominated diphenyl ether (BDE-99), one of the most frequently reported congeners in freshwater biota, the inhibition of algal growth of Raphidocelis subcapitata (also known as Selenastrum capricornutum) and acute toxicity to Daphnia magna were examined. The experimental design also involved a comparison with the polychlorinated biphenyl (PCB) Aroclor 1254®. The uptake of BDE-99 by R. subcapitata and the transfer to D. magna (i.e., a higher level of aquatic biota in the food chain) was also assessed to verify the bioaccumulation phenomenon. After 24h, BDE-99 appeared to be less toxic than Aroclor 1254 to D. magna, but the two compounds showed a similar toxicity at 48h. In contrast to Aroclor 1254, BDE-99 was nontoxic to R. subcapitata at up to 100 μM, the highest tested concentration. However, the dose-dependent decrease in survival and impairment of reproduction of D. magna fed with BDE-99-treated algal culture demonstrate uptake by R. subcapitata. Because of the high persistence and bioconcentration, polybrominated diphenyl ethers as well as PCBs might be of environmental concern for years.
Water quality guidance for protection of freshwater mussels (Unionidae) from ammonia exposure
Authors: Augspurger Tom , Keller Anne E. , Black Marsha C. , Cope W. Gregory , Dwyer F. James
Published: November 2004

Ammonia toxicity data for freshwater mussels (Unionidae), a significantly imperiled taxa, were used to derive estimates of concentrations that would not likely be harmful in acute and chronic exposures and to assess the protectiveness of current U.S. Environmental Protection Agency (U.S. EPA) water quality criteria to this family of organisms. Thirty acute (24–96-h) median lethal concentrations (LC50s), covering 10 species in eight unionid genera, were used to calculate genus mean acute values (GMAVs) ranging from 2.56 to 8.97 mg/L total ammonia as N at pH 8. Freshwater mussels are at the sensitive end of the range when added to the GMAVs from the database used to derive the U.S. EPA criteria maximum concentration (CMC). We derived two estimates of acute exposure water quality guidance for the protection of freshwater mussels (CMCFM) by a recalculation of the CMC after adding freshwater mussel GMAVs to the U.S. EPA data set. The CMCFMs of 1.75 and 2.50 mg/L total ammonia as N at pH 8 average 60% less than the U.S. EPA CMC of 5.62 mg/L total ammonia as N at pH 8 for application when salmonids are present. These values average about 75% less than the CMC for application when salmonids are absent. No chronic ammonia exposure data existed for unionids. Thus, we applied a range of estimated acute:chronic ratios to the acute toxicity data set, expanded with the freshwater mussel GMAVs, to estimate continuous ammonia concentrations that may be protective of freshwater mussels. These estimates ranged from 0.3 to 1.0 mg/L total ammonia as N at pH 8, about 20 to 75% less than the U.S. EPA criteria continuous concentration (CCC) of 1.24 mg/L total ammonia as N at pH 8 and 25°C. The current numeric criteria for ammonia may not be protective of mussels, more than half of whose nearly 300 species are in decline in North America. While the CMCFM and CCCFM are not equivalent to revised U.S. EPA criteria, they are offered as interim guidance for the protection of freshwater mussels.
Sensitivity of juvenile freshwater mussels (Lampsilis fasciola, Villosa iris) to total and un-ionized ammonia
Authors: Mummert Andrea K. , Neves Richard J. , Newcomb Tammy J. , Cherry Donald S.
Published: November 2004

This study evaluated the sensitivity of juveniles of two freshwater unionid mussel species (Villosa iris [Lea] and Lampsilis fasciola [Rafinesque]) to un-ionized and total ammonia. Five concentrations of ammonium chloride were tested using 96-h staticrenewal toxicity tests at 12 and 20°C. Based on their respective mean 96-h lethal concentration to 50% (LC50s), V. iris (0.11 mg/ L NH3-N) was more sensitive than L. fasciola (0.26 mg/L NH3-N). At 96 h, significant differences in sensitivity to un-ionized ammonia between the two temperatures were not observed for either species. Comparison of LC50s reported for other aquatic organisms to the 96-h LC50s calculated for juvenile L. fasciola and V. iris shows these two mussel species to be among the most sensitive to un-ionized ammonia. Based on reported levels of un-ionized ammonia in the aquatic environment from anthropogenic sources, un-ionized ammonia may be an important limiting toxicological factor to freshwater mussel populations.
Effect of nonaqueous-phase liquids on the availability of polycyclic aromatic hydrocarbons in soil for worm uptake and bacterial genotoxicity
Authors: Quiñones-Rivera Antonio , Alexander Renee R. , Alexander Martin
Published: November 2004

A study was conducted to determine the effect of nonaqueous-phase liquids (NAPLs) on the bioavailability of benzo[a]pyrene (BaP) in soil. Sentry 19 oil and pristane reduced the availability of BaP for assimilation by the earthworm Eisenia fetida and for mutagenicity in a rifampicin-sensitive strain of Pseudomonas putida. As much as 80% of the compound could be rendered unavailable to the worms or for genotoxicity. Tests with five alkanes and an oil showed that the extent of reduction in genotoxicity of BaP varied with the identity, viscosity, and hydrophobicity of the NAPL. The magnitude of the decline in availability for genotoxicity differed in tests of three soils. Because little or no BaP was lost from the soil, the diminished bioavailability was not the result of a diminished total concentration of the compound. These findings show that exposure to hydrophobic toxicants can be appreciably altered in soils containing NAPLs.
Temperature influences on water permeability and chlorpyrifos uptake in aquatic insects with differing respiratory strategies
Authors: Buchwalter David B. , Jenkins Jeffrey J. , Curtis Lawrence R.
Published: November 2004

Aquatic insects have evolved diverse respiratory strategies that range from breathing atmospheric air to breathing dissolved oxygen. These strategies result in vast morphological differences among taxa in terms of exchange epithelial surface areas that are in direct contact with the surrounding water that, in turn, affect physiological processes. This paper examines the effects of acute temperature shifts on water permeability and chlorpyrifos uptake in aquatic insects with different respiratory strategies. While considerable differences existed in water permeability among the species tested, acute temperature shifts raised water influx rates similarly in air-breathing and gill-bearing taxa. This contrasts significantly with temperature-shift effects on chlorpyrifos uptake. Temperature shifts of 4.5°C increased 14C-chlorpyrifos accumulation rates in the gill-bearing mayfly Cinygma sp. and in the air-breathing hemipteran Sigara washingtonensis. However, the temperature-induced increase in 14C-chlorpyrifos uptake after 8 h of exposure was 2.75-fold higher in Cinygma than in Sigara. Uptake of 14C-chlorpyrifos was uniformly higher in Cinygma than in Sigara in all experiments. These findings suggest that organisms with relatively large exchange epithelial surface areas are potentially more vulnerable to both osmoregulatory distress as well as contaminant accumulation. Temperature increases appear more likely to impact organisms that have relatively large exchange epithelial surface areas, both as an individual stressor and in combination with additional stressors such as contaminants.
Concentrations of organochlorine pesticides and polychlorinated biphenyls in amphipods (Gammarus lacustris) along an elevation gradient in mountain lakes of western Canada
Authors: Blais Jules M. , Wilhelm Frank , Kidd Karen A. , Muir Derek C. G. , Donald David B. , Schindler David W.
Published: November 2004

Populations of the amphipod Gammarus lacustris were examined for their concentrations of organochlorine pesticides and polychlorinated biphenyls (PCBs) from seven lakes spanning a 1,300-m elevation gradient in Alberta, Canada. The concentrations of several of the semivolatile organochlorine compounds ([SVOCs], vapor pressure > 0.03 Pa at 20°C) increased at higher altitudes. This pattern was generally not observed among the less volatile organochlorines ([LVOCs], vapor pressure < 0.03 Pa at 20°C). These same SVOC compounds have been previously shown to increase at high latitudes as a result of their long-range transport and preferential deposition in cold climates. We also show that populations of G. lacustris at high elevations have slower growth rates and store more lipids than populations at lower elevations. To resolve the colinearity of independent variables, we used multiple regression to identify patterns of contaminant concentrations in this data set. Multiple regressions showed that the effect of elevation, lipid content, and temperature on contaminant concentrations was no longer significant once the growth rate of Gammarus was included as an independent variable. This study shows that enrichment of SVOCs occurs in Gammarus at high altitudes in Alberta, Canada, and that growth rate (biodilution) appears to be the primary influence. Because Gammarus is an important trophic link in aquatic foodwebs in these environments, enhanced concentrations of toxicants in prey may increase their biomagnification in top predators of high-altitude lakes.
Chemical contaminants and biological indicators of mussel health during gametogenesis
Authors: Hellou Jocelyne , Yeats Phil , Steller Sean , Gagné Francois
Published: November 2004

Mytilus edulis were collected intertidally from three locations in Halifax Harbor, Nova Scotia, on five occasions during spring and summer 2000. Bioindicators of health (lipid content), condition and gonad indices (CI and GI), and sex ratio, as well as vitellins, were compared with the bioaccumulation of polycyclic aromatic compounds (PACs) including polycyclic aromatic hydrocarbons (PAHs), polychlorinated biphenyls (PCBs), coprostanol, and metals. Twice as many male as female mussels were collected from a downtown site (M8) close to numerous raw sewage effluents and a naval dockyard. Males from M8 had a high lipid content, and females had a delayed production of vitellins. These mussels also displayed the highest levels of PACs, coprostanol, Ag, and Sn. Coprostanol and silver are sewage markers in sediments, and their presence in mussels confirms exposure to sewage effluents. Female mussels were more abundant in an area outside the industrialized part of the harbor that had higher marine traffic (M14); displayed higher levels of vitellins in gonads; had similar time trends for CI and GI; and had some similar metals compared with mussels from M8. The lowest variability in biomarkers was observed at a site in a mostly residential arm of the harbor (M12), which was expected to be more pristine based on an earlier investigation. Compared to mussels in M14, the mussels of M12 had the lowest condition indices and PCB concentrations and low but similar levels of lipids, PACs, and coprostanol. They also displayed the highest concentrations of Cd, Cu, Pb, and Hg, and females had the highest gonad indices early in the season.
Limitations of current risk characterization methods in probabilistic environmental risk assessment
Authors: Verdonck Frederik A. M. , Aldenberg Tom , Jaworska Joanna , Vanrolleghem Peter A.
Published: November 2004

In probabilistic environmental risk assessment, the likelihood and the extent of adverse effects occurring in ecological systems because of exposure(s) to substances are estimated. It is based on the comparison of an exposure/environmental concentration distribution, with a species sensitivity distribution derived from toxicity data. The calculation of a probabilistic risk can be performed in many ways (e.g., area under the curve in joint probability curves). However, several (hypothetical) examples and some theoretical considerations illustrate that the current risk characterisation methods have an integrative character and they focus on the statistical comparison of two distributions without properly considering the environmental interpretation of these underlying distributions. Several scenarios with varying exposure/environmental concentration distribution and species sensitivity distribution standard deviations are discussed.
Determination of the surface sorption properties of talc, different salts, and clay minerals at various relative humidities using adsorption data of a diverse set of organic vapors
Authors: Goss Kai-Uwe , Buschmann Johanna , Schwarzenbach René P.
Published: November 2004

Adsorption constants of a diverse set of organic vapors have been measured on NaCl, KNO3, (NH4)2SO4, NH4Cl, kaolinite, bentonite, and talc at different relative humidities at 15°C. Together with the earlier studied quartz (SiO2), CaCO3, and α-Al2O3, these surfaces represent relevant sorbents for organic vapors in the environment. An equation that describes the van der Waals and H-bond interactions between the sorbate and the surface can be used to describe the sorbate and sorbent variability in the measured data and to predict sorption constants of organic compounds that have not been tested on the respective surface. The unknown properties of the sorbent surfaces are used as fitting parameters in this equation. These data provide important insights into the variability of sorption properties of natural, inorganic surfaces as a function of relative humidity.
Bright and Efficient, Non‐Doped, Phosphorescent Organic Red‐Light‐Emitting Diodes
Authors: Song Y.‐H. , Yeh S.‐J. , Chen C.‐T. , Chi Y. , Liu C.‐S. , Yu J.‐K. , Hu Y.‐H. , Chou P.‐T. , Peng S.‐M. , Lee G.‐H.
Published: November 2004

Ir(III)metal complexes with formula [(nazo)2Ir(Fppz)] (1), [(nazo)2Ir(Bppz)] (2), and [(nazo)2Ir(Fptz)] (3) [(nazo)H = 4‐phenyl quinazoline, (Fppz)H = 3‐trifluoromethyl‐5‐(2‐pyridyl) pyrazole, (Bppz)H = 3‐t‐butyl‐5‐(2‐pyridyl) pyrazole, and (Fptz)H = 3‐trifluoromethyl‐5‐(2‐pyridyl) triazole] were synthesized, among which the exact configuration of1was confirmed using single‐crystal X‐ray diffraction analysis. These complexes exhibited bright red phosphorescence with relatively short lifetimes of 0.4–1.05 μs in both solution and the solid‐state at room temperature. Non‐doped organic light‐emitting diodes (OLEDs) were fabricated using complexes1and2in the absence of a host matrix. Saturated red electroluminescence was observed at λmax = 626 nm (host‐emitter complex 1) and 652 nm (host‐emitter complex 2), which corresponds to coordinates (0.66,0.34) and (0.69,0.31), respectively, on the 1931 Commission Internationale de l'Eclairage (CIE) chromaticity diagram. The non‐doped devices employing complex 1showed electroluminance as high as 5780 cd m–2, an external quantum efficiency of 5.5 % at 8 V, and a current density of 20 mA cm–2. The short phosphorescence lifetime of1in the solid state, coupled with its modest π–π stacking interactions, appear to be the determining factors for its unusual success as a non‐doped host‐emitter.
Titelbild: Atomic‐Step‐Templated Formation of Single Wall Carbon Nanotube Patterns (Angew. Chem. 45/2004)
Authors: Ismach Ariel , Segev Lior , Wachtel Ellen , Joselevich Ernesto
Published: November 2004

Die Anordnung von Nanodrähten ist eine wichtige Voraussetzung für die Herstellung von Nanoschaltkreisen. Auf S. 6266 ff. schildern E. Joselevich et al., wie einwandige Kohlenstoff‐Nanoröhren entlang den atomaren Stufen benachbarter Oberflächen gebildet werden, wobei stark ausgerichtete, dichte Anordnungen diskreter, nanometerbreiter Drähte entstehen. Die Nanoröhren (blaues AFM‐Bild) reproduzieren die atomaren Eigenschaften der Oberfläche (rotes Modell).
Intraoperative adverse events and outcome after anterior resection of the rectum
Authors: Matthiessen P , Hallböök O , Rutegård J , Sjödahl R
Published: November 2004

Background

The aim of this population-based study was to analyse the relationship between intraoperative adverse events and outcome after anterior resection.

Methods

All 140 patients who underwent elective anterior resection in Sweden between 1987 and 1995, and who died within 30 days, were compared with a group of 423 randomly selected patients who underwent the same procedure during the same interval but survived the operation. Intraoperative adverse events and intraoperative measures taken were analysed in relation to outcome of surgery.

Results

Of those who died, 45·7 per cent had intraoperative adverse events compared with 30·3 per cent in the cohort group. Major bleeding, gross spillage of faeces, and two or more intraoperative adverse events were more common among those who died. When the anastomosis was considered unsatisfactory, it was more frequently reconstructed (restapled or completely resutured), with or without a temporary stoma, in those who survived. The use of a temporary stoma was comparable in the two groups when adverse events were present.

Conclusion

Intraoperative adverse events were important contributors to morbidity and mortality. Complete reconstruction of an unsatisfactory anastomosis, with or without addition of a temporary stoma, was more frequently performed in the survivors, and may have diminished the risk of postoperative death.
Early impact of centralization of oesophageal cancer surgery services
Authors: Branagan G , Davies N
Published: November 2004

Background

In response to national guidance, oesophageal surgery from four hospitals within Wessex was centralized to a single site, with a provision for surgeons to travel to the centre to operate if they wished. This study assessed the clinical impact of this change.

Methods

Data for patients who had oesophageal cancer surgery at the single site were collected prospectively for 1 year from May 2002 and compared with the Wessex Oesophageal Cancer Audit (WOCA) data for the four hospitals from 1999 to 2000.

Results

Thirty-three patients underwent surgery on the single site compared with 40 patients from the four hospitals during the WOCA. Age, sex, co-morbidity, tumour site, and preoperative tumour and node stage were similar in the two groups. Six patients from the WOCA underwent ‘open and close’ laparotomy compared with none in the single-site group (P = 0·020). There were four anastomotic leaks in the WOCA group and two in the single-site group. Overall complication rates in those undergoing resection were similar in the two groups, but the in-hospital mortality rate was significantly higher in the WOCA group (five versus no patients; P = 0·022). Pathology reporting was incomplete in significantly more patients in the WOCA group (15 versus three; P = 0·001). The mean node harvest was greater in the single-site group (30·5 versus 19).

Conclusion

Centralization of oesophageal surgery resulted in better preoperative staging, a lower 30-day mortality rate and more complete pathological reporting.
Presentation, treatment and outcome in patients with ampullary tumours
Authors: Bettschart V , Rahman M Q , Engelken F J F , Madhavan K K , Parks R W , Garden O J
Published: November 2004

Background

Ampullary tumours are relatively rare, and few large single-centre reports provide information on their treatment and outcome. The aim of this study was to analyse outcome and determine predictors of survival for patients with ampullary tumours treated in a specialist centre.

Methods

Over an 11-year period, 561 patients were treated for periampullary tumours, 88 of whom had a histologically proven ampullary neoplasm. Prospectively gathered data were analysed to assess predictors of survival.

Results

The overall resection rate was 92 per cent; there were no postoperative deaths. Median survival was 45·8 months for patients with resectable tumours and 8·0 months for those with irresectable disease (P < 0·001). On univariate analysis, age less than 70 years (P = 0·015) and a bilirubin level of 75 µmol/l or less (P = 0·012) favoured long-term survival. Among 70 patients who underwent cancer resection, factors associated with significantly worse long-term survival on univariate analysis included poorly differentiated tumour (P < 0·001), positive nodes (P < 0·001), perineural invasion (P = 0·001) and invasion of the pancreas (P = 0·018). Multivariate analysis identified positive nodes and bilirubin concentration as independent predictors of survival.

Conclusion

An aggressive surgical approach to ampullary tumours is justified by the low proportion of benign lesions, the absence of postoperative mortality and improved long-term survival.
Auslegung und Optimierung von Suspendierrührwerken
Authors: Einenkel W.‐D.
Published: November 2004

No abstracts.
Theoretische und experimentelle Untersuchungen der Mischvorgänge in T‐förmigen Mikroreaktoren – Teil 3: Konvektives Mischen und chemische Reaktionen
Authors: Kockmann N. , Engler M. , Woias P.
Published: November 2004

No abstracts.
Anwendung von dimensionslosen Kennzahlen zur Auslegung von Feinsttropfenabscheidern
Authors: Heikamp W.
Published: November 2004

No abstracts.
Association of Cu2+with Uracil and Its Thio Derivatives: A Theoretical Study
Authors: Lamsabhi Al Mokhtar , Alcamí Manuel , Mó Otilia , Yáñez Manuel , Tortajada Jeanine
Published: November 2004

The structures and relative stabilities of the complexes between Cu2+and uracil, 2‐thiouracil, 4‐thiouracil, and 2,4‐dithiouracil were investigated by B3LYP/6‐311+G(2df,2p)//B3LYP/6‐31G* DFT calculations. In those systems in which both types of basic centers, that is, a carbonyl and a thiocarbonyl group, are present, association of Cu2+with the oxygen atom is systematically favored, in contrast to what was found for the corresponding Cu+complexes. This can be understood by considering that association of Cu2+is immediately followed by oxidation of the base, which accumulates the negative charge at the oxygen atoms. Similarly, for 2,4‐dithiouracil the most basic site for Cu+attachment is the sulfur atom at the 4‐position, while for association of Cu2+it is the sulfur atom at the 2‐position. In contrast, differences between uracil–Cu+and uracil–Cu2+complexes are very small, and in both cases the oxygen atom at the 4‐position is the most basic. Cu2+binding energies are about 4 and 1.2 times larger than Cu+binding energies and proton affinities, respectively. Uracil– and thiouracil–Cu2+complexes are thermodynamically unstable but kinetically stable with respect to their dissociation into uracil.++Cu+or thiouracil.++Cu+. The Cu2+binding energies vary with the difference between the second ionization potential of the metal and the first ionization potential of the base. regardless of the reference acid (H+, Cu+, Cu2+) the basicity trend is 2,4‐dithiouracil>4‐thiouracil>2‐thiouracil>uracil.
Role of pharmacogenomics in drug development
Authors: Hakonarsson Hakon , Stefansson Kari
Published: November 2004

Pharmacogenomics is charged with the task of uncovering genetic variations that underlie responses to drugs. While the results in the field have been slow in coming, more recent high‐throughput screening methods and data‐mining approaches are expected to effectively expedite the drug development process in the near future. While these new techniques are likely to reduce costs, the selection of the most pertinent study cohort with respect to the biological mechanism of the study compound is a critical element in risk management. Enrichment of the study cohort with carriers of “at‐risk” variants in genes that reside within and/or influence the biological pathway targeted by the drug candidate, would be expected to lower the risk of drug failure, while both delivering faster and better results at lower costs. In this context, at deCODE Genetics, Inc., the powerful coupling of family‐based linkage to ultra‐high throughput genotyping, gene array, and proteomics technology, together with innovative bioinformatic resources, provides a focused integrative strategy for pinpointing disease‐causing genes that may generate validated drug targets and genes that are responsible for differential response to drugs. deCODE has compiled one of the world's most comprehensive collection of population data on genealogy, genotypes, and phenotypes. This combination of resources provides an effective system for uncovering genes that predispose to disease or regulate drug response. In addition, this approach allows for the development of novel therapeutic strategies and diagnostic tests that, apart from being applicable to assessment of disease susceptibility and clinical response to drugs, provide for an effective clinical trial design, ultimately leading to safer and more efficacious drugs for patients. Drug Dev. Res. 62:86–96, 2004. © 2004 Wiley‐Liss, Inc.