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Terms modified by Several Selected AbstractsFormaldehyde-releasers: relationship to formaldehyde contact allergy.CONTACT DERMATITIS, Issue 2 2009Contact allergy to formaldehyde, inventory of formaldehyde-releasers This is one of series of review articles on formaldehyde and formaldehyde-releasers (others: formaldehyde in cosmetics, in clothes and in metalworking fluids and miscellaneous). Thirty-five chemicals were identified as being formaldehyde-releasers. Although a further seven are listed in the literature as formaldehyde-releasers, data are inadequate to consider them as such beyond doubt. Several (nomenclature) mistakes and outdated information are discussed. Formaldehyde and formaldehyde allergy are reviewed: applications, exposure scenarios, legislation, patch testing problems, frequency of sensitization, relevance of positive patch test reactions, clinical pattern of allergic contact dermatitis from formaldehyde, prognosis, threshold for elicitation of allergic contact dermatitis, analytical tests to determine formaldehyde in products and frequency of exposure to formaldehyde and releasers. The frequency of contact allergy to formaldehyde is consistently higher in the USA (8,9%) than in Europe (2,3%). Patch testing with formaldehyde is problematic; the currently used 1% solution may result in both false-positive and false-negative (up to 40%) reactions. Determining the relevance of patch test reactions is often challenging. What concentration of formaldehyde is safe for sensitive patients remains unknown. Levels of 200,300 p.p.m. free formaldehyde in cosmetic products have been shown to induce dermatitis from short-term use on normal skin. [source] Potassium-transporting proteins in skeletal muscle: cellular location and fibre-type differencesACTA PHYSIOLOGICA, Issue 2 2010M. Kristensen Abstract Potassium (K+) displacement in skeletal muscle may be an important factor in the development of muscle fatigue during intense exercise. It has been shown in vitro that an increase in the extracellular K+ concentration ([K+]e) to values higher than approx. 10 mm significantly reduce force development in unfatigued skeletal muscle. Several in vivo studies have shown that [K+]e increases progressively with increasing work intensity, reaching values higher than 10 mm. This increase in [K+]e is expected to be even higher in the transverse (T)-tubules than the concentration reached in the interstitium. Besides the voltage-sensitive K+ (Kv) channels that generate the action potential (AP) it is suggested that the big-conductance Ca2+ -dependent K+ (KCa1.1) channel contributes significantly to the K+ release into the T-tubules. Also the ATP-dependent K+ (KATP) channel participates, but is suggested primarily to participate in K+ release to the interstitium. Because there is restricted diffusion of K+ to the interstitium, K+ released to the T-tubules during AP propagation will be removed primarily by reuptake mediated by transport proteins located in the T-tubule membrane. The most important protein that mediates K+ reuptake in the T-tubules is the Na+,K+ -ATPase ,2 dimers, but a significant contribution of the strong inward rectifier K+ (Kir2.1) channel is also suggested. The Na+, K+, 2Cl, 1 (NKCC1) cotransporter also participates in K+ reuptake but probably mainly from the interstitium. The relative content of the different K+ -transporting proteins differs in oxidative and glycolytic muscles, and might explain the different [K+]e tolerance observed. [source] Tumoral and tissue-specific expression of the major human ,-tubulin isotypes,CYTOSKELETON, Issue 4 2010Luis J. Leandro-García Abstract The ,-tubulins are microtubule components encoded by a multigene family, which produces slightly different proteins with complex expression patterns. Several widely used anticancer drugs base their activity on ,-tubulin binding, microtubule dynamics alteration, and cell division blockage. The expression of these drug targets in tumoral and normal cells could be of crucial importance for therapy outcome, unfortunately, the complex ,-tubulin expression patterns have been poorly characterized in human. In this study, we developed a quantitative RT-PCR technique that accurately determines the mRNA expression of the eight human ,-tubulin isotypes, encoding class I, IIa, IIb, III, IVa, IVb, V, and VI and applied it to 21 nontumoral tissues and 79 tumor samples belonging to seven cancer types. In the nontumoral tissues, we found that, overall, TUBB (I), TUBB2C (IVb), and TUBB6 (V) were ubiquitous, TUBB1(VI) was hematopoietic cell-specific, and TUBB2A (IIa), TUBB2B (IIb), TUBB3 (III), and TUBB4 (IVa) had high expression in brain; however, the contribution of the different isotypes to the total ,-tubulin content varied for each tissue and had a complex pattern. In tumoral tissues, most isotypes exhibited an altered expression in specific tumor types or related to tumoral characteristics. In general, TUBB3 showed a great increase in expression while TUBB6 expression was largely decreased in most tumors. Thus, normal tissues showed a complex ,-tubulin isotype distribution, which could contribute to the toxicity profile of the microtubule-binding drugs. In addition, the specific isotypes significantly altered in tumors might represent markers for drug response. © 2010 Wiley-Liss, Inc. [source] Myosin diversity in the diatom Phaeodactylum tricornutum,CYTOSKELETON, Issue 3 2010Matthew B. Heintzelman Abstract This report describes the domain architecture of ten myosins cloned from the pennate diatom Phaeodactylum tricornutum. Several of the P. tricornutum myosins show similarity to myosins from the centric diatom Thalassiosira pseudonana as well as to one myosin from the oomycete Phytophthora ramorum. The P. tricornutum myosins, ranging in size from 126 kDa to over 250 kDa, all possess the canonical head, neck and tail domains common to most myosins, though variations in each of these domains is evident. Among the features distinguishing several of the diatom myosin head domains are N-terminal SH3-like domains, variations in or near the P-loop and Loop 1 regions close to the nucleotide binding pocket, and extended converter domains. Variations in the length of the neck domain or lever arm, defined by the light chain-binding IQ motifs, are apparent with the different diatom myosins predicted to contain from one to nine IQ motifs. Protein domains found within the P. tricornutum myosin tails include regions of coiled-coil structure, ankyrin repeats, CBS domain pairs, a PB1 domain, a kinase domain and a FYVE-finger motif. As many of these features have never before been characterized in myosins of any type, it is likely that these new diatom myosins will expand the repertoire of known myosin behaviors. © 2010 Wiley-Liss, Inc. [source] Multiple Primary Acral Melanomas in African-Americans: A Case Series and Review of the LiteratureDERMATOLOGIC SURGERY, Issue 1 2007ANGELA C. S. HUTCHESON MD BACKGROUND Although melanoma accounts for only 4% to 5% of all skin cancers in the United States, it causes most skin cancer,related deaths. We describe a unique group of African-American patients with multiple primary acral lentiginous melanomas (ALMs). OBJECTIVE The purpose of this study was to review the case histories and management of a cohort of patients in the Mohs practice of our dermatologic surgeon with multiple primary ALM. METHODS This is a case series of patients with multiple ALM identified by chart review from 2000 to 2005. A thorough review of the literature was performed. RESULTS Four patients, all African-American, were identified with multiple ALM. All patients were managed with excision or Mohs micrographic surgery utilizing permanent sections. None of the patients with ALM had melanomas at nonacral sites or other types of skin cancer. Several had acral melanosis. Information in the literature on patients with multiple primary acral melanomas was insufficient. CONCLUSION Patients with multiple acral melanomas have not, to our knowledge, been reported thus far. It can be extrapolated from current literature, however, that appropriate management of these patients, including staging work and surgical intervention, is to be determined by the individual characteristics of the melanoma and the patient's concomitant risk factors, if any. [source] Coordinated and conserved expression of alphoid repeat and alphoid repeat-tagged coding sequencesDEVELOPMENTAL DYNAMICS, Issue 1 2003Yin-Xiong Li Abstract We have found an alpha-like simple-sequence DNA repeat that is differentially expressed during early embryogenesis in both chick and zebrafish. Before and during the primitive streak stage, transcripts of the alphoid repeat sequence were ubiquitously expressed throughout zebrafish and chick embryos. After headfold formation, expression was limited to the cardiac neural crest, the head, and the heart. Two types of alphoid repeat sequence transcripts were identified: alphoid repeat RNA and alphoid repeat-tagged mRNA (ES,T). Several of the ES,Ts were identified by (1) searching expressed sequence tag databases, (2) arbitrary rapid amplification of cDNA ends (RACE), and (3) screening embryonic cDNA libraries. The alphoid element was located in the 3, untranslated region of one ES,T that was obtained by RACE. The ES,T sequences encoded a variety of different types of proteins, but all were expressed within tissues that were positive for the alphoid repeat RNA. The presence of two types of coordinately expressed alphoid-like repeat transcripts in maternal RNA with subsequent restriction to the head and heart, and the conservation of these features in disparate vertebrate embryos, suggest that the alphoid repeat sequence may serve as a control element in the gene regulation network. Developmental Dynamics 228:72,81, 2003. © 2003 Wiley-Liss, Inc. [source] Fine-needle aspiration cytology of salivary glands: Diagnostic pitfalls,revisitedDIAGNOSTIC CYTOPATHOLOGY, Issue 8 2006Arvind Rajwanshi M.D., F.R.C.Path. Abstract Fine needle aspiration cytology (FNAC) of salivary gland lesions is a safe, effective diagnostic technique. Several amply illustrated reviews are available in the English literature. The reported diagnostic accuracy varies between 86% to 98%. The sensitivity ranges from 62% to 97.6% and specificity is higher from 94.3% to 100%. In this present study, we have analyzed 172 cases of salivary gland aspirates and the histopathological diagnosis was available in 45 cases. There was discordance in cytological and histopathological diagnosis in nine cases. Five cases had discrepancies in benign versus malignant diagnosis with four cases being false negative. The errors in these FNA diagnoses were due to sampling error, observational error and interpretational error. Therefore, this study illustrates high diagnostic accuracy of FNAC in salivary gland lesions and shows that FNAC offers valuable information that allows the planning of subsequent patient management. Diagn. Cytopathol. 2006;34:580,584. © 2006 Wiley-Liss, Inc. [source] Defining and measuring braiding intensityEARTH SURFACE PROCESSES AND LANDFORMS, Issue 14 2008Roey Egozi Abstract Geomorphological studies of braided rivers still lack a consistent measurement of the complexity of the braided pattern. Several simple indices have been proposed and two (channel count and total sinuosity) are the most commonly applied. For none of these indices has there been an assessment of the sampling requirements and there has been no systematic study of the equivalence of the indices to each other and their sensitivity to river stage. Resolution of these issues is essential for progress in studies of braided morphology and dynamics at the scale of the channel network. A series of experiments was run using small-scale physical models of braided rivers in a 3 m , 20 m flume. Sampling criteria for braid indices and their comparability were assessed using constant-discharge experiments. Sample hydrographs were run to assess the effect of flow variability. Reach lengths of at least 10 times the average wetted width are needed to measure braid indices with precision of the order of 20% of the mean. Inherent variability in channel pattern makes it difficult to achieve greater precision. Channel count indices need a minimum of 10 cross-sections spaced no further apart than the average wetted width of the river. Several of the braid indices, including total sinuosity, give very similar numerical values but they differ substantially from channel-count index values. Consequently, functional relationships between channel pattern and, for example, discharge, are sensitive to the choice of braid index. Braid indices are sensitive to river stage and the highest values typically occur below peak flows of a diurnal (melt-water) hydrograph in pro-glacial rivers. There is no general relationship with stage that would allow data from rivers at different relative stage to be compared. At present, channel count indices give the best combination of rapid measurement, precision, and range of sources from which measurements can be reliably made. They can also be related directly to bar theory for braided pattern development. Copyright © 2008 John Wiley & Sons, Ltd. [source] Role of Echocardiography in Assessing the Mechanism and Effect of Ramipril on Functional Mitral Regurgitation in Dilated CardiomyopathyECHOCARDIOGRAPHY, Issue 4 2005D.M. (Card), F.I.A.E., F.I.A.M.S., F.I.C.C., F.I.C.P., I.B. Vijayalakshmi M.D. The objectives of this article are to determine the possible mechanism of functional mitral regurgitation in patients with dilated cardiomyopathy (DCM) and to know the effect of ramipril on left ventricle (LV) and mitral regurgitation by ECHO. Several postulates are put forth for functional mitral regurgitation in DCM, and mitral annular dilatation is said to be the primary mechanism in the past, but the exact mechanism is not clear. Though angiotensin converting enzyme (ACE) inhibitors are known to remodel the LV, their beneficial effect in patients with DCM with functional mitral regurgitation is not known. Various cardiac dimensions and degree of mitral regurgitation were measured by echocardiography in 30 normal control group and in 30 patients with DCM of various etiologies except ischemic, before and after ramipril therapy. There was a significant difference in all parameters especially sphericity of left ventricle and position of papillary muscles (P < 0.0003) in DCM patients, but mitral valve annulus did not show significant change (P < 0.3) compared to control group. In 50% of the patients, the functional mitral regurgitation totally disappeared. In 30% of patients, it came down from grade II to I or became trivial. In 20% of patients, it remained unchanged. There was remarkable improvement in sphericity, LV dimension, volumes, and EF%, which increased from 31 ± 9.81 to 39.3 ± 8.3% (P < 0.0003). It is concluded that echocardiography clearly demonstrates the increased sphericity of LV in DCM. The lateral migration of papillary muscles possibly plays a major role in functional mitral regurgitation. Ramipril significantly reduces not only sphericity but also functional mitral regurgitation. [source] Alcohol control policies and alcohol consumption by youth: a multi-national studyADDICTION, Issue 11 2009Mallie J. Paschall ABSTRACT Aims The study examined relationships between alcohol control policies and adolescent alcohol use in 26 countries. Design Cross-sectional analyses of alcohol policy ratings based on the Alcohol Policy Index (API), per capita consumption and national adolescent survey data. Setting Data are from 26 countries. Participants Adolescents (aged 15,17 years) who participated in the 2003 European School Survey Project on Alcohol and Other Drugs (ESPAD) or national secondary school surveys in Spain, Canada, Australia, New Zealand and the United States. Measurements Alcohol control policy ratings based on the API; prevalence of alcohol use, heavy drinking and first drink by age 13 based on national secondary school surveys; per capita alcohol consumption for each country in 2003. Analysis Correlational and linear regression analyses were conducted to examine relationships between alcohol control policy ratings and past 30-day prevalence of adolescent alcohol use, heavy drinking and having first drink by age 13. Per capita consumption of alcohol was included as a covariate in regression analyses. Findings More comprehensive API ratings and alcohol availability and advertising control ratings were related inversely to the past 30-day prevalence of alcohol use and prevalence rates for drinking three to five times and six or more times in the past 30 days. Alcohol advertising control was also related inversely to the prevalence of past 30-day heavy drinking and having first drink by age 13. Most of the relationships between API, alcohol availability and advertising control and drinking prevalence rates were attenuated and no longer statistically significant when controlling for per capita consumption in regression analyses, suggesting that alcohol use in the general population may confound or mediate observed relationships between alcohol control policies and youth alcohol consumption. Several of the inverse relationships remained statistically significant when controlling for per capita consumption. Conclusions More comprehensive and stringent alcohol control policies, particularly policies affecting alcohol availability and marketing, are associated with lower prevalence and frequency of adolescent alcohol consumption and age of first alcohol use. [source] Factors affecting the reproductive biology of Melittobia digitata and failure to meet the sex ratio predictions of Hamilton's local mate competition theoryENTOMOLOGIA EXPERIMENTALIS ET APPLICATA, Issue 1 2003M.F. Cooperband Abstract Melittobia digitata Dahms (Eulophidae, Tetrastichini), a species of parasitic wasp satisfying all of Hamilton's local mate competition requisites, does not exhibit the predicted change in sex ratio with increased foundress number. A multifactorial design was used to test how age, oviposition experience, feeding experience, mating, and foundress number affect host-acceptance, number of offspring, and sex ratio of this species developing on honey bee pupae, Apis mellifera (L.) (Apidae, Apini). All factors significantly affected the time it took for oviposition to commence. Females oviposited soonest when they were 2 days old, mated, had previous feeding and oviposition experience, and were placed on hosts with multiple foundresses. Although the age difference between 2- and 5-day-old females is small, it significantly affected reproductive behavior. Age, mating, and foundress number were found to have an effect on sex ratio, however, the foundress effect was found to be a mathematical artifact of the limited host size. After correcting for this variable, females were found to have a constant sex ratio of approximately 0.05. Several 2-way interactions between factors were revealed: age and experience, age and foundress number, age and mating, foundress number and experience, and foundress number and mating. One 3-way interaction was found between age, mating, and foundress number. This study demonstrates that the sex ratio of M. digitata is not altered with increased foundresses, as predicted by Hamilton, and that slight changes in preconditioning may modify reproductive behavior. [source] Diversity of functional genes of methanogens, methanotrophs and sulfate reducers in deep-sea hydrothermal environmentsENVIRONMENTAL MICROBIOLOGY, Issue 1 2005Olivier Nercessian Summary To contribute to the identification of methanogens, methanotrophs and sulfate-reducing bacteria (SRB) in microbial communities from the 13°N (East Pacific Rise) and Rainbow (Mid-Atlantic Ridge) hydrothermal vent fields, we investigated the diversity of mcrA, pmoA and dsrAB genes sequences. Clone libraries were obtained using DNA isolated from fragments of diffuse vents, sediment and in situ samplers. The clones were categorized by restriction fragment length polymorphism, and representatives of each group were sequenced. Sequences were related to that of hyperthermophilic (order Methanopyrales and family Methanocaldococcaceae), thermophilic and mesophilic (family Methanococcaceae) methanogens, thermophilic (proposed genus ,Methylothermus') and mesophilic type I methanotrophs, and hyperthermophilic (order Archaeoglobales), thermophilic (order Thermodesulfobacteriales) and mesophilic (family Desulfobulbaceae) SRB. Several of the obtained sequences were distantly related to the genes of cultivated organisms, providing evidence of the existence of novel lineages in the three functional groups. This study provides for the first time an insight into the diversity of several functional genes of deep-sea hydrothermal system microorganisms. [source] Presence and distribution of wastewater-derived pharmaceuticals in soil irrigated with reclaimed waterENVIRONMENTAL TOXICOLOGY & CHEMISTRY, Issue 2 2006Chad A. Kinney Abstract Three sites in the Front Range of Colorado, USA, were monitored from May through September 2003 to assess the presence and distribution of pharmaceuticals in soil irrigated with reclaimed water derived from urban wastewater. Soil cores were collected monthly, and 19 pharmaceuticals, all of which were detected during the present study, were measured in 5-cm increments of the 30-cm cores. Samples of reclaimed water were analyzed three times during the study to assess the input of pharmaceuticals. Samples collected before the onset of irrigation in 2003 contained numerous pharmaceuticals, likely resulting from the previous year's irrigation. Several of the selected pharmaceuticals increased in total soil concentration at one or more of the sites. The four most commonly detected pharmaceuticals were erythromycin, carbamazepine, fluoxetine, and diphenhydramine. Typical concentrations of the individual pharmaceuticals observed were low (0.02,15 ,g/kg dry soil). The existence of subsurface maximum concentrations and detectable concentrations at the lowest sampled soil depth might indicate interactions of soil components with pharmaceuticals during leaching through the vadose zone. Nevertheless, the present study demonstrates that reclaimed-water irrigation results in soil pharmaceutical concentrations that vary through the irrigation season and that some compounds persist for months after irrigation. [source] An epidemiological study of risk factors associated with the recurrence of equine grass sickness (dysautonomia) on previously affected premisesEQUINE VETERINARY JOURNAL, Issue 2 2004J. R. Newton Summary Reasons for performing study: The reasons why equine grass sickness (EGS) recurs on premises are unknown and, consequently, practical methods for reducing the risk of recurrence are not available. Objectives: To identify risk factors associated with recurrence of EGS on premises and to gain possible insights into the pathogenesis of the disease. Methods: Data on disease history and risk factors were collected by postal questionnaire from premises with EGS cases between 1st January 1997 and 31st December 2001. Data on variation in rates of recurrence of EGS for different risk factors were analysed using Poisson regression analysis. Results: Of 509 premises contacted, 305 (60%) returned useable questionnaires and 100 of these (33%) were classified as ,recurrent' premises. An overall median incidence rate for EGS of 2.1 EGS incidents/100 horses/premises/year was recorded. There was an increased rate of recurrence with higher numbers of horses, presence of younger animals, stud farms and livery/riding establishments, loam and sand soils, rearing of domestic birds and mechanical droppings removal. The rate of recurrence decreased with chalk soil, cograzing ruminants, grass cutting on pastures and removal of droppings by hand. Several statistically significant interactions were identified. Conclusions: Many of the findings are consistent with the theory that EGS is a toxico-infectious form of botulism. Several of the significant factors identified may directly or indirectly relate to soil disturbance and consequent soil contamination of grass, thereby increasing the rate of exposure of grazing horses to Clostridium botulinum, which resides in soil. Potential relevance: Identification of potentially modifiable risk factors may, ideally following validation in appropriately designed, controlled and randomised intervention studies, lead to practical measures to reduce the incidence of EGS on previously affected premises. [source] ,You can't go without a fag . . . you need it for your hash',a qualitative exploration of smoking, cannabis and young peopleADDICTION, Issue 1 2004Amanda Amos ABSTRACT Aims To examine the relationship between smoking tobacco and cannabis use among smokers in their mid-to-late teens. Design and participants Two qualitative studies in Scotland. One study used semistructured paired interviews involving 99 16,19-year-old smokers, the other comprised eight focus groups involving 46 15,16-year-old smokers. Measurement The interviews and focus groups explored the role and meaning of smoking in the participants' lives, smoking histories and future cessation intentions and how these related to other aspects of their lives, particularly cannabis use. Findings Cannabis use was regarded as an important and enjoyable aspect of many of the participants' lives. Importantly, cannabis use and cigarette smoking were linked inextricably. Several reported how smoking joints had been a ,gateway' to smoking cigarettes. While most wanted to quit smoking cigarettes, cannabis use reinforced their cigarette smoking and few wanted to stop using cannabis. Conclusion National studies need to be conducted to examine how widespread the problem identified is and tobacco control initiatives and smoking cessation treatment services need to consider urgently how to overcome the barrier that a desire on the part of young people to continue cannabis smoking poses to achieving a reduction in tobacco use. [source] Renal phosphate handling in human , what can we learn from hereditary hypophosphataemias?EUROPEAN JOURNAL OF CLINICAL INVESTIGATION, Issue 6 2010Stefan Amatschek Eur J Clin Invest 2010; 40 (6): 552,560 Abstract Background, Renal reabsorption of inorganic phosphate is critical for the maintenance of phosphate homeostasis. The sodium dependent phosphate cotransporters NaPi-IIa and NaPi-IIc have been identified to fulfill this task at the brush border membrane of proximal tubule cells. Various factors including dietary phosphate intake, parathyroid hormone, or the so called phosphatonins such as FGF23 have been shown to regulate activity of these transporters. Design, This review seeks to give an update on our current knowledge about regulatory mechanisms involved in human renal phosphate reabsorption. Results, Recently, an increasing number of genes have been identified that are directly associated with inherited phosphate wasting disorders (Klotho, PHEX, DMP1 and NHERF1). Several of these genes are predominantly expressed by osteocytes and osteoclasts in the bone suggesting indispensable signalling pathways between kidneys and the skeleton. Conclusion, In this review, the affected gene products in these inherited hypophosphataemias and their contribution to phosphate homeostasis are discussed. [source] Impaired estrogen-induced negative feedback on gonadotropin secretion in patients with gonadotropin-secreting and nonfunctioning pituitary adenomasEUROPEAN JOURNAL OF CLINICAL INVESTIGATION, Issue 5 2002A. Lania Abstract Background Several in vitro studies suggest that gonadotropin-secreting pituitary adenomas (Gn-omas) and non functioning pituitary adenomas (NFPA) originate from gonadotroph cells. Patients with Gn-oma and NFPA frequently show abnormal gonadotropin response to TRH. The aim of the study was to investigate whether the estrogen-induced negative feedback is operating in either patients with Gn-oma or NFPA. Materials and methods Serum gonadotropin levels were evaluated at 24 h after ethinylestradiol administration (1 mg per os; EE2 test) in seven patients with a diagnosis of Gn-oma, based on the presence of high follicle-stimulating hormone (FSH) and/or lutenising hormone (LH) levels with normal or high levels of sex steroids, in 22 patients with NFPA with normal or low levels of gonadotropin and sex steroids, and 30 sex- and age-matched healthy subjects. A normal response to EE2 test was arbitrarily defined as a serum LH and FSH decrease of at least 40 and 30% below basal levels. Results Among patients with Gn-oma, only one had a normal FSH inhibition and another, a normal LH inhibition. Among the 22 patients with NFPA, the EE2 test caused a normal FSH or LH reduction in 10 and 15, respectively, while a normal reduction of both FSH and LH was observed in nine. Conclusions The study demonstrates that estrogen-induced negative feedback of gonadotropin secretion is disrupted in almost all patients with Gn-oma and in half of those with NFPA. This defective feedback is reminiscent of the resistance to thyroid hormones and glucocorticoids observed in patients with thyroid-stimulating hormone- (TSH-) and adrenocorticotropic hormone- (ACTH-)secreting adenomas, respectively. [source] Cobalt(II) Complexes with Substituted Salen-Type Ligands and Their Dioxygen Affinity in N,N -Dimethylformamide at Various TemperaturesEUROPEAN JOURNAL OF INORGANIC CHEMISTRY, Issue 8 2005Andreas Huber Abstract Several unsymmetrically substituted salen-type cobalt(II) Schiff-base complexes CoL [H2L = 1,6-bis(2-hydroxyphenyl)-3,3-dimethyl-2,5-diaza-1,5-hexadiene (1); 1,6-bis(2-hydroxyphenyl)-3,3-dimethyl-2,5-diaza-1,5-heptadiene (2); 1-(3- tert -butyl-2-hydroxy-5-methylphenyl)-6-(2-hydroxyphen-yl)-3,3-dimethyl-2,5-diaza-1,5-heptadiene (3); 1-(2-hydroxyphenyl)-6-methyl-2,5-diaza-1,5-nonadien-8-one (4); 1-(3- tert -butyl-2-hydroxy-5-methylphenyl)-6-methyl-2,5-di-aza-1,5-nonadien-8-one (5); 1-(2-hydroxyphenyl)-3,3,6-trimethyl-2,5-diaza-1,5-nonadien-8-one (6); 1-(3- tert -butyl-2-hydroxy-5-methylphenyl)-3,3,6-trimethyl-2,5-diaza-1,5-nonadien-8-one (7)] were prepared and characterized by their UV/Vis absorption spectra, magnetic moments, and oxidation potentials. Except for complex 4 (irreversible oxidation with t½ , 3 h), complexes 1,3 and 5,7 are remarkably resistant against irreversible auto-oxidation in air-saturated N,N -dimethylformamide (DMF) at ambient temperature. To characterize the Lewis acidity of the cobalt center in 1,7, the equilibrium constant Kpy was determined for monoadduct formation with pyridine (CoL + pyCoL·py). An O2 -sensitive optode was used to determine the Henry constant, KH, for the system O2/DMF in the temperature range 298,228 K. The formation of 1:1 adducts of complexes 1,7 with O2 in DMF, as characterized by the equilibrium constant K, was followed spectrophotometrically in the temperature range 298,228 K. The parameters ,Ho, ,So, and K are reported. At 298 K, K ranges from 21.9 M,1 (5) to 155 M,1 (7). The overall spectroscopic information, including EPR spectra obtained with frozen solutions of 3 and 7 in O2 -saturated DMF, confirm that the 1:1 adducts CoL·O2 are cobalt(III) superoxo compounds. The symmetrically substituted salen complex8 [H2L = 1,6-bis(3- tert -butyl-2-hydroxy-5-methylphenyl)-3,3,4,4-tetramethyl-2,5-diaza-1,5-hexadiene in 8] is shown to catalyze the oxidation of triphenylphosphane and 2,6-di- tert -butylphenol by O2 in DMF at ambient temperature. The correlation of the data obtained for K, Kpy, and the oxidation potential E½ is discussed. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2005) [source] Heterobimetallic Systems Containing Organometallic and Classical Coordination Sites: Effects of Subtle Changes in the Werner-Type SiteEUROPEAN JOURNAL OF INORGANIC CHEMISTRY, Issue 7 2005Tianlu Sheng Abstract Several highly unsymmetrical heterodinuclear Mn/Zn complexes are reported, in which an organometallic CpMn-(CO)2 fragment and a classical Werner-type zinc coordination unit are arranged in close proximity by means of a bridging pyrazolate. Ligand scaffolds differing in the chelate size of the tripodal tetradentate {N4} binding site, and different coligands for zinc are employed. Both the zinc-devoid precursor compounds and the bimetallic complexes with zinc(II) nested in the tris(pyridylalkyl)amine type {N4} compartment have been characterized by X-ray crystallography. Structural and spectroscopic features as well as the redox potentials of the MnI/MnII couple indicate slight effects of the redox-inactive Werner-type subunit on the properties of the organometallic site. Oxidation is highly localized at the organometallic manganese site, as is evidenced by IR and EPR spectroscopy and supported by DFT calculations. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2005) [source] Cellular prion protein/laminin receptor: distribution in adult central nervous system and characterization of an isoform associated with a subtype of cortical neuronsEUROPEAN JOURNAL OF NEUROSCIENCE, Issue 10 2004Hasna Baloui Abstract The 67-kDa LR protein was originally discovered as a non-integrin laminin receptor. Several more recent in vitro studies demonstrated the function of 67-kDa LR and its related ,precursor' form 37-kDa LRP as receptors of cellular prion protein and their implication in abnormal prion protein propagation in vitro. In addition, expression of both proteins was shown to increase considerably in the brain of scrapie-infected mice and hamsters. While LRP/LR are thus likely to play important roles in neuronal cell adhesion, survival and homeostasis and during pathological disorders, little is known so far about their fine cellular distribution in adult central nervous system. Using immunocytochemistry and western blotting, we show here that the 67-kDa LR is the major receptor form in adult rat brain and spinal cord, expressed within the cytoplasm and at the plasma membrane of most neurons and in a subset of glial cells. The overall distribution of LR correlates well with that reported for laminin-1 but also with brain regions classically associated with prion-related neurodegeneration. In contrast to LR, the 37-kDa LRP form is much less abundant in adult than in postnatal central nervous system. Characterization of a novel antibody allowed us to study the distribution across tissues of cell membrane-associated LRP. Interestingly, this form is almost exclusively found on a subclass of parvalbumin-immunoreactive cortical interneurons known to degenerate during the early stages of Creutzfeldt-Jakob disease. Our demonstration of local differences in the expression of particular LRP/LR isoforms may be a first step towards unraveling their specific molecular interactions. [source] The organization of visual object representations: a connectionist model of effects of lesions in perirhinal cortexEUROPEAN JOURNAL OF NEUROSCIENCE, Issue 2 2002Timothy J. Bussey Abstract We have developed a simple connectionist model based on the idea that perirhinal cortex has properties similar to other regions in the ventral visual stream, or ,what' pathway. The model is based on the assumption that representations in the ventral visual stream are organized hierarchically, such that representations of simple features of objects are stored in caudal regions of the ventral visual stream, and representations of the conjunctions of these features are stored in more rostral regions. We propose that a function of these feature conjunction representations is to help to resolve ,feature ambiguity', a property of visual discrimination problems that can emerge when features of an object predict a given outcome (e.g. reward) when part of one object, but predict a different outcome when part of another object. Several recently reported effects of lesions of perirhinal cortex in monkeys have provided key insights into the functions of this region. In the present study these effects were simulated by comparing the performance of connectionist networks before and after removal of a layer of units corresponding to perirhinal cortex. The results of these simulations suggest that effects of lesions in perirhinal cortex on visual discrimination may be due not to the impairment of a specific type of learning or memory, such as declarative or procedural, but to compromising the representations of visual stimuli. Furthermore, we propose that attempting to classify perirhinal cortex function as either ,perceptual' or ,mnemonic' may be misguided, as it seems unlikely that these broad constructs will map neatly onto anatomically defined regions of the brain. [source] A multivariate analysis of the outcome of endodontic treatmentEUROPEAN JOURNAL OF ORAL SCIENCES, Issue 3 2004Dag Ørstavik In the present study, multivariate analyses were performed on clinical and treatment variables that may influence the outcome of endodontic treatment. Data collected in a previous clinical-radiographic follow-up study were used. Of 810 treated, 675 roots in 498 teeth were followed for 6 months to 4 yr. Of these, 192 (the CAP group) had pre-existing, chronic apical periodontitis and 483 (the NAP group) had not. Root canal treatment followed a standard procedure with one of three sealers chosen at random. Demographic, clinical and radiographic variables were recorded at the start of, and during treatment. The periapical index (PAI) score was used to record the outcome of treatment, and applied in two different endpoint modes (END1 and END2) as the dependent variable for multivariate statistical analyses using logistic regression and the general model. The modes reflected increasing PAI scores (END1) and conventional success/failure assessment (END2). Dropouts were largely similar to the cases followed up. A total of 10 preoperative and peroperative variables were found to be significantly associated with treatment outcome by the multivariate analyses of either the total material or the NAP or CAP subgroups. Several of these were not significant in univariate analyses (e.g. the effect of sealer). Conventional success/failure analyses (END2) identified fewer of the influential variables and had low explanatory power, whereas PAI scores on an ordinal scale (END1) were most sensitive in identifying variables of influence on the treatment outcome. [source] Alkoxy-5-nitrosopyrimidines: Useful Building Block for the Generation of Biologically Active CompoundsEUROPEAN JOURNAL OF ORGANIC CHEMISTRY, Issue 20 2010Antonio Marchal Abstract Several alkoxy-5-nitrosopyrimidines were synthesised and high regioselective and sequential nucleophilic aromatic substitution of methoxy groups in 2-amino-4,6-dimethoxy-5-nitrosopyrimidine was observed. The approach was applied to the synthesis of valuable polyfunctionalised aminopyrimidines capable of mimicking fused heterobicyclic derivatives of biological interest. In addition, new compounds were evaluated as antivirals and their usefulness as synthetic intermediates was demonstrated. [source] 2H -Pyrrole Derivatives from an Aza-Nazarov Reaction Cascade Involving Indole as the Neutral Leaving GroupEUROPEAN JOURNAL OF ORGANIC CHEMISTRY, Issue 21 2008Nugzar Ghavtadze Abstract Trifluoromethyl-substituted N -indolinyl-1-aza-1,4-dien-3-ones 4, which are accessible in good yields from indolinylimino esters 6 in a two-step procedure, undergo a novel type of aza-Nazarov cyclization if treated with strong acids to give the hitherto unknown 3-hydroxy-5H -pyrrole derivatives 8a,p. The solvent-free polyphosphoric acid/acyl anhydride system as the acidic reaction medium is especially efficient and requires only short reaction times. According to quantum chemical calculations the key step in the reaction cascade is the cleavage of the N,N bond of the hydrazone fragment of a protonated N -(indolin-1-yl)-1-aza-1,4-dien-3-one intermediate such as 10. This intermediate releases 3H -indole as an unusual, but very efficient neutral leaving group. Several 1-aza-1,4-dien-3-ones 4 and some 3-hydroxy-5H -pyrrole derivatives 8 were characterized by X-ray diffraction.(© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2008) [source] Novel Pyrazines from the Myxobacterium Chondromyces crocatus and Marine BacteriaEUROPEAN JOURNAL OF ORGANIC CHEMISTRY, Issue 19 2005Jeroen S. Dickschat Abstract The volatiles released by two strains of the myxobacterium Chondromyces crocatus and seven strains of marine Alphaproteobacteria from the North Sea were collected using the CLSA or SPME headspace methods and analysed by GC-MS. In the extracts of C. crocatus 27 pyrazines were identified, belonging to different classes. 2,5-Dialkylpyrazines and related 3-methoxy-2,5-dialkylpyrazines dominated. Several pyrazines like 2-(1-methylethenyl)-5-(1-methylethyl)pyrazine (7) and 3-methoxy-2,5-dialkylpyrazines with methyl, isopropyl, isobutyl or sec -butyl side-chains were obtained from natural sources for the first time. It was essential for the identification to rely on synthetic reference materials, which were obtained using Fürstner's iron-catalysed coupling of chloropyrazines with Grignard reagents or condensation of azido ketones as key steps. The synthetic material allowed the identification of two previously unknown attractants of bacterial origin for the pineapple beetle Carpophilus humeralis, namely 3-methoxy-2-(1-methylpropyl)-5-(2-methylpropyl)pyrazine (17) and 3-methoxy-2,5-bis(1-methylpropyl)pyrazine (52). Several 2,5-dialkylpyrazines were identified in the extracts of the marine Alphaproteobacteria. The unique 2,5-dimethyl-3-(methylsulfanyl)pyrazine (67) represents a new type of natural pyrazine. Our results, together with literature reports, show that pyrazines are an important class of bacterial volatiles which might be more widespread than previously thought. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2005) [source] Preparation of Sugar Amino Acids by Claisen-Johnson Rearrangement: Synthesis and Incorporation into Enkephalin AnaloguesEUROPEAN JOURNAL OF ORGANIC CHEMISTRY, Issue 14 2004Ana Montero Abstract We have developed a convenient route for the synthesis of an unsaturated branched sugar bearing a carboxylic acid and an amino group (masked as an azide group) by employing a totally stereoselective Claisen,Johnson rearrangement as the key step. Several Met- and Leu-enkephalin analogues with different substitution patterns at the N - and C -termini were prepared by incorporating this sugar amino acid (SAA) as a substitute for the central Gly,Gly fragment of the parent pentapeptides. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2004) [source] Validation of the UPPS impulsive behaviour scale: a four-factor model of impulsivityEUROPEAN JOURNAL OF PERSONALITY, Issue 7 2005Stephen P. Whiteside The current study attempts to clarify the multi-faceted nature of impulsivity through the use of the four-factor UPPS Impulsive Behaviour scale. In order to build the nomological network surrounding this scale, the UPPS was administered to individuals with borderline personality disorder (BPD), pathological gamblers (PG), alcohol abusers (divided into two groups based on the presence of antisocial features), and a control group. Several of the UPPS scales (e.g. Urgency, lack of Premeditation, and Sensation Seeking) differentiated the BPD, PG, and alcohol abusers with antisocial features from a group of non-antisocial alcohol abusers and a control group. Overall, the UPPS scales accounted for between 7% (pathological gambling) and 64% (borderline personality disorder features) of the overall variance in the psychopathology measures. Individual UPPS scales also made unique contributions to several of these disorders, which may provide insight into which of these personality traits may predispose individuals to behave in maladaptive or problematic ways. The results provide support for the differentiation of impulsivity-related constructs into the current four-factor model. Copyright © 2005 John Wiley & Sons, Ltd. [source] Determining soil saturated hydraulic conductivity and sorptivity from single ring infiltration testsEUROPEAN JOURNAL OF SOIL SCIENCE, Issue 1 2007J. Touma Summary The difference between the cumulative infiltration occurring during three-dimensional axisymmetric and one-dimensional vertical flow is a linear function of time. The slope of this line is a function of the source radius, initial and final volumetric soil water contents and the soil sorptivity. This allows the determination of the sorptivity and saturated conductivity of the soil from data of axisymmetric flow in a single ring of small diameter under negligible head of water. The method is based on the optimization of the sorptivity and saturated conductivity on the one-dimensional vertical cumulative infiltration inferred from axisymmetric flow data. To examine the reliability of the method to determine these parameters, numerical three- and one-dimensional data are generated on soils with known hydrologic properties from the literature. The linearity versus time of the difference of the two types of flow is verified. Several physically based expressions for the vertical cumulative infiltration as a function of time are considered. The optimized values of the sorptivity and saturated conductivity are compared to the their real known values. Despite the large errors on the optimized parameters, namely the saturated conductivity, the error on the vertical predicted cumulative infiltration is limited to 10%. This makes possible the application of this method on a large scale for hydrological modelling purposes. [source] Human telomeric G-quadruplex: The current status of telomeric G-quadruplexes as therapeutic targets in human cancerFEBS JOURNAL, Issue 5 2010Stephen Neidle The 3,-ends of human chromosomal DNA terminate in short single-stranded guanine-rich tandem-repeat sequences. In cancer cells, these are associated with the telomere-maintenance enzyme telomerase together with the end-binding protein hPOT1. Small molecules that can compete with these proteins and induce the single-stranded DNA to form quadruplex,ligand complexes are, in effect, able to expose these 3,-ends, which results in the activation of a DNA damage response and selective inhibition of cell growth. Several of these G-quadruplex binding molecules have shown promising anticancer activity in tumour xenograft models, which indicate that the approach may be applicable to the treatment of a wide range of human cancers. This minireview summarizes the available data on these compounds and the challenges posed for drug discovery. [source] Mapping of the 45M1 epitope to the C-terminal cysteine-rich part of the human MUC5AC mucinFEBS JOURNAL, Issue 3 2008Martin E. Lidell Mucins are large glycoproteins protecting mucosal surfaces throughout the body. Their expressions are tissue-specific, but in disease states such as cystic fibrosis, inflammation and cancer, this specificity can be disturbed. MUC5AC is normally expressed in the mucous cells of the epithelia lining the stomach and the trachea, where it constitutes a major component of the gastric and respiratory mucus. A number of mAbs have been raised against the gastric M1 antigen, an early marker for colonic carcinogenesis. Several of these mAbs recognize epitopes present on MUC5AC, suggesting that MUC5AC is the antigen. However, some of the mAbs raised against the gastric M1 antigen are widely used as antibodies against MUC5AC, despite the fact that their specificity for MUC5AC has not been clearly shown. In this study, we have tested the reactivity of the latter antibodies against a recombinantly expressed C-terminal cysteine-rich part of human MUC5AC. We demonstrate for the first time that the widely used mAb 45M1, as well as 2-12M1 and 166M1, are true antibodies against MUC5AC, with epitopes located in the C-terminal cysteine-rich part of the mucin. [source] | |||||||||||||||||||||||||||||||||||||||||||||||||