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Little Importance (little + importance)
Selected AbstractsUnusual cone and rod properties in subterranean African mole-rats (Rodentia, Bathyergidae)EUROPEAN JOURNAL OF NEUROSCIENCE, Issue 6 2004Leo Peichl Abstract We have determined the presence of spectral cone types, and the population densities of cones and rods, in subterranean mole-rats of the rodent family Bathyergidae, for which light and vision seems of little importance. Most mammals have two spectral cone types, a majority of middle- to long-wave-sensitive (L-) cones, and a minority of short-wave-sensitive (S-)cones. We were interested to see whether the subterranean bathyergids show the same pattern. In three species, Ansell's mole-rat Cryptomys anselli, the giant mole-rat Cryptomys mechowi and the naked mole-rat Heterocephalus glaber, spectral cone types and rods were assessed immunocytochemically with opsin-specific antibodies. All three species had rod-dominated retinae but possessed significant cone populations. A quantitative assessment in C. anselli and C. mechowi revealed surprisingly low photoreceptor densities of 100 000,150 000/mm2, and high cone proportions, , 10% (8000,15 000/mm2). In all three species, the vast majority of the cones were strongly S-opsin-immunoreactive; L-opsin immunoreactivity was much fainter. In C. anselli, , 20% of the cones showed exclusive S-opsin label, , 10% exclusive L-opsin label and , 70% strong S-opsin and faint L-opsin double label (potential dual-pigment cones). This is the first observation in any mammal of an S-opsin dominance and low levels of L-opsin across the entire retina. It contrasts starkly with the situation in the muroid blind mole-rat Spalax ehrenbergi, which has been reported to possess L-opsin but no S-opsin. Evidently, within rodents an adaptation to subterranean life is compatible with very different spectral cone properties. [source] Amino acids Thr56 and Thr58 are not essential for elongation factor 2 function in yeastFEBS JOURNAL, Issue 20 2007Galyna Bartish Yeast elongation factor 2 is an essential protein that contains two highly conserved threonine residues, T56 and T58, that could potentially be phosphorylated by the Rck2 kinase in response to environmental stress. The importance of residues T56 and T58 for elongation factor 2 function in yeast was studied using site directed mutagenesis and functional complementation. Mutations T56D, T56G, T56K, T56N and T56V resulted in nonfunctional elongation factor 2 whereas mutated factor carrying point mutations T56M, T56C, T56S, T58S and T58V was functional. Expression of mutants T56C, T56S and T58S was associated with reduced growth rate. The double mutants T56M/T58W and T56M/T58V were also functional but the latter mutant caused increased cell death and considerably reduced growth rate. The results suggest that the physiological role of T56 and T58 as phosphorylation targets is of little importance in yeast under standard growth conditions. Yeast cells expressing mutants T56C and T56S were less able to cope with environmental stress induced by increased growth temperatures. Similarly, cells expressing mutants T56M and T56M/T58W were less capable of adapting to increased osmolarity whereas cells expressing mutant T58V behaved normally. All mutants tested were retained their ability to bind to ribosomes in vivo. However, mutants T56D, T56G and T56K were under-represented on the ribosome, suggesting that these nonfunctional forms of elongation factor 2 were less capable of competing with wild-type elongation factor 2 in ribosome binding. The presence of nonfunctional but ribosome binding forms of elongation factor 2 did not affect the growth rate of yeast cells also expressing wild-type elongation factor 2. [source] Migraine Prevention: What Patients Want From Medication and Their Physicians (A Headache Specialty Clinic Perspective)HEADACHE, Issue 5 2006Todd D. Rozen MD Objective.,To document the results of a migraine patients survey, from a headache specialty clinic, in which patients were asked to rank, in order of importance, certain characteristics of migraine preventive treatment. Methods.,A 10-question survey was completed by 150 patients (114 females and 36 males) with a history of migraine who presented to the Michigan Head Pain & Neurological Institute. The patients were asked to rank, in order of importance, characteristics of migraine preventive treatment. Each characteristic was rated individually on a 1 to 10 scale (1 being of little importance and 10 being extremely important). The mean rating of each characteristic was then calculated and the results analyzed. Results/Discussion.,From this migraine preventive treatment survey, the most important thing to migraineurs, from a headache specialty clinic population, is that the prescribing physician involves them in the decision making of choosing a preventive agent. The physician taking time to explain the possible medication side effects is the second most highly ranked characteristic. Migraine preventives with published efficacy in the medical literature are also deemed very important. Migraineurs do not mind using more than 1 preventive agent at one time if greater efficacy can be achieved. Agents that may affect weight and /or cause sedation may be important factors as to why patients (especially females) may not want to take a preventive medication. Natural therapies and once-daily dosing are ranked lower overall but still are important characteristics of preventive treatment. Some gender differences are noted in the ranking of migraine preventive characteristics. [source] OCCUPATIONAL SPECIFICITY OF HUMAN CAPITAL,INTERNATIONAL ECONOMIC REVIEW, Issue 1 2009Gueorgui Kambourov We find that returns to occupational tenure are substantial. Everything else being constant, 5 years of occupational tenure are associated with an increase in wages of 12%,20%. Moreover, when occupational experience is taken into account, tenure with an industry or employer has relatively little importance in accounting for the wage one receives. This finding is consistent with human capital being occupation specific. [source] Molecular structure, conformational analysis and charge distribution of pralidoxime: Ab initio and DFT studiesINTERNATIONAL JOURNAL OF QUANTUM CHEMISTRY, Issue 3 2002Alexandre T. Castro Abstract A detailed structural study of pralidoxime (2-PAM), the main antidote against organophosphate intoxication, was performed using Hartree-Fock, Möller,Plesset (MP2), and density functional theory (Becke, Lee, Yang, and Paar [B3LYP]) methods. Rotational barriers, equilibrium geometries, and charge distributions were calculated, showing important differences between the two forms available in physiological conditions, namely with the oxime group protonated or unprotonated. For the protonated form, conjugation between the side chain and the pyridinium ring, although present, has little importance, resulting in a flexible structure. On the other hand, the unprotonated form has a more rigid structure and a smaller charge density on the oxime oxygen. Contrary to the common belief, those results strongly suggest that it may be the protonated form of 2-PAM, instead of the unprotonated form, that is responsible for the antidote activity of this compound. © 2002 Wiley Periodicals, Inc. Int J Quantum Chem, 2002 [source] The infectivity of transmissible spongiform encephalopathy agent at low doses: the importance of phospholipidJOURNAL OF APPLIED MICROBIOLOGY, Issue 2 2006P. Gale Abstract The issue of whether the mechanism of infection is independent or co-operative for low doses of transmissible spongiform encephalopathy (TSE) agent is critical for risk assessment. The susceptibility (and hence ID50) of individuals with the same prion protein (PrP) genotype may vary considerably with a small proportion being very susceptible. Assuming independent action, the incubation period (IP) would continue to increase until the dose is below the ID50 of the most susceptible individuals in the experiment, at which point it would become constant. This may explain the observed increase in IP with decreasing dose below the apparent ID50 in experiments with untreated TSE agent. In contrast, IPs for autoclaved or NaOH-treated TSE agent increase greatly at doses Neuronal uptake and metabolism of glycerol and the neuronal expression of mitochondrial glycerol-3-phosphate dehydrogenaseJOURNAL OF NEUROCHEMISTRY, Issue 4 2003Nga Huynh Tran Nguyen Abstract Glycerol is effective in the treatment of brain oedema but it is unclear if this is due solely to osmotic effects of glycerol or whether the brain may metabolize glycerol. We found that intracerebral injection of [14C]glycerol in rat gave a higher specific activity of glutamate than of glutamine, indicating neuronal metabolism of glycerol. Interestingly, the specific activity of GABA became higher than that of glutamate. NMR spectroscopy of brains of mice given 150 µmol [U- 13C]glycerol (0.5 m i.v.) confirmed this predominant labelling of GABA, indicating avid glycerol metabolism in GABAergic neurones. Uptake of [14C]glycerol into cultured cerebellar granule cells was inhibited by Hg2+, suggesting uptake through aquaporins, whereas Hg2+ stimulated glycerol uptake into cultured astrocytes. The neuronal metabolism of glycerol, which was confirmed in experiments with purified synaptosomes and cultured cerebellar granule cells, suggested neuronal expression of glycerol kinase and some isoform of glycerol-3-phosphate dehydrogenase. Histochemically, we demonstrated mitochondrial glycerol-3-phosphate dehydrogenase in neurones, whereas cytosolic glycerol-3-phosphate dehydrogenase was three to four times more active in white matter than in grey matter, reflecting its selective expression in oligodendroglia. The localization of mitochondrial and cytosolic glycerol-3-phosphate dehydrogenases in different cell types implies that the glycerol-3-phosphate shuttle is of little importance in the brain. [source] Articulatory Phonetics in the First-Year Spanish ClassroomMODERN LANGUAGE JOURNAL, Issue 3 2000Deborah L. Arteaga focus of this article is twofold: I reconsider the general question of the role of articulatory phonetics in the second language (L2) classroom and review the phonetics presentation in 10 recent first-year Spanish texts. Pronunciation has been accorded little importance within recent methodological approaches, although their stated goals of communication and intelligibility in fact require the incorporation of explicit phonetics instruction in the language classroom. Considering the first-year Spanish L2 classroom, I propose a phonetics program based on the notion of a learner's dialect (cf. Bergen, 1974). I then measure the phonetics presentation of 10 Spanish textbooks against a learner's dialect, and find that pronunciation sections are in most cases incomplete and inaccurate and provide for no self-monitoring or recycling. This article argues against the current trend reflected in these texts, which relegates pronunciation to the laboratory manual or eliminates it altogether. [source] Inheritance of useful traits in cassava grown in subhumid conditionsPLANT BREEDING, Issue 2 2006N. T. Cach Abstract A diallel study among nine parental clones of cassava was conducted in the subhumid environment on the northern coast of Colombia. Analysis of variance suggested significant effects for the six variables analysed: fresh-root yield, harvest index, root dry matter content, height of first branching, reaction to thrips and plant-type scores. General and specific combining ability effects and their interaction with the environment were significant for most of the variables as well. Results suggested that dominance plays a particularly important role in the cases of fresh-root yield and harvest index but had relatively little importance in the reaction to thrips, dry matter content or height of first branching. Specific breeding approaches are suggested for these traits, depending on the relative importance of additive or non-additive effects in their inheritance. The correlations among different traits were also analysed and in several cases their magnitude reached statistical and biological significance. [source] Effects of Constant, 9 and 16-h Light Cycles on Sperm Quality, Semen Storage Ability and Motile Sperm Subpopulations Structure of Boar SemenREPRODUCTION IN DOMESTIC ANIMALS, Issue 5 2006MM Rivera Contents This study was performed to test the effect that two separate, daily, constant-light regimes of both 9 and 16 h could have on the main parameters of boar-semen quality analysis, as well as on the motile sperm subpopulations structure and the ability of its conservation at 16°C. Results show that both luminous regimes have slight, specific effects on the main parameters of boar-semen quality analysis, as well as on the motile sperm subpopulations structure. Furthermore, the conservation ability at 16°C of boar semen was not significantly different between both photoperiods. When a temporal study was performed, results showed that semen quality and motility parameter changes were stabilized at nearly constant values from the second month of the study to the last month in both luminous regimes, indicating a rapid light-related effect on testicular function. Our results indicate that light regimes oscillating from 9 h daily to 16 h daily are of little importance in the control of boar-semen quality in a farming environment. [source] What are we saving?ANIMAL CONSERVATION, Issue 3 2009Developing a standardized approach for conservation action Abstract Are all species equal in terms of conservation attention? We developed a novel framework to assess the level of conservation attention given to 697 threatened mammals and 100 critically endangered amphibian species. Our index of conservation attention provides a quantitative framework for assessing how conservation resources are allocated, based on the degree to which conservation interventions have been proposed and implemented. Our results provide evidence of the strong biases in global conservation attention. We find that most threatened species receive little or no conservation, and that the small number receiving substantial attention is extremely biased. Species most likely to receive conservation attention are those which are well-studied, charismatic and that live in the developed world. Conservation status and evolutionary distinctiveness appear to have little importance in conservation decision-making at the global scale. Most species inhabit the tropics and are both poorly known and uncharismatic. Therefore, the majority of biodiversity is being ignored by current conservation action. [source] Socio-economic characteristics in children with coeliac diseaseACTA PAEDIATRICA, Issue 1 2005J. F. Ludvigsson Abstract Aim: To study the relationship between socio-economic factors and coeliac disease. Methods: This study was part of a prospective cohort study of 16,286 children born from 1 October 1997,1 October 1999 (the ABIS study; All Babies in Southeast Sweden). Eight paediatric departments recorded all children with coeliac disease in southeast Sweden. Coeliac disease was confirmed through biopsy. Socio-economic characteristics (maternal employment, civil status, whether parents were born in Sweden, parental education, place of living before pregnancy and during pregnancy, crowded living), infant sex, previous siblings, parental age and maternal alcohol consumption during pregnancy were analysed using logistic regression. All data, except for those related to diagnosis of coeliac disease, were obtained through a questionnaire distributed at birth. Results: Coeliac disease in the offspring was less common among mothers who had worked <3 mo during pregnancy (odds ratio, OR=0.29; 95% CI: 0.09,0.94; p=0.039). This risk decrease remained after adjustment for confounders (adjusted OR=0.28; 95% CI: 0.09,0.92; p=0.035). No other socio-economic factor was related to coeliac disease. Conclusion: This study indicates that most socio-economic factors are probably of little importance to the development of coeliac disease. [source]
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