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1.
Nat Commun ; 12(1): 3960, 2021 06 25.
Artigo em Inglês | MEDLINE | ID: mdl-34172727

RESUMO

The Greenland Ice Sheet harbours a wealth of microbial life, yet the total biomass stored or exported from its surface to downstream environments is unconstrained. Here, we quantify microbial abundance and cellular biomass flux within the near-surface weathering crust photic zone of the western sector of the ice sheet. Using groundwater techniques, we demonstrate that interstitial water flow is slow (~10-2 m d-1), while flow cytometry enumeration reveals this pathway delivers 5 × 108 cells m-2 d-1 to supraglacial streams, equivalent to a carbon flux up to 250 g km-2 d-1. We infer that cellular carbon accumulation in the weathering crust exceeds fluvial export, promoting biomass sequestration, enhanced carbon cycling, and biological albedo reduction. We estimate that up to 37 kg km-2 of cellular carbon is flushed from the weathering crust environment of the western Greenland Ice Sheet each summer, providing an appreciable flux to support heterotrophs and methanogenesis at the bed.


Assuntos
Biomassa , Camada de Gelo/microbiologia , Carbono/análise , Ciclo do Carbono , Contagem de Colônia Microbiana , Groenlândia , Hidrologia , Camada de Gelo/química , Tempo (Meteorologia)
2.
Pharmacol Biochem Behav ; 196: 172996, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32668266

RESUMO

Opiate analgesics are one of the treatment options for severe chronic pain, including late-stage cancer, chronic back pain and other disorders. The recent resurgence in opioid overdose has highlighted the serious need for alternative medicines for pain management. While a role for potentiators of α2/3-containing GABAA receptors in the modulation of pain has been known for several years, advancements in this area required data from selective compounds. KRM-II-81(5-(8-ethynyl-6-(pyridin-2-yl)-4H-benzo[f]imidazo[1,5-a][1,4]diazepin-3- yl)oxazole) and analogs selectively potentiate GABAA receptors containing α2/3 subunits and have recently been shown to attenuate pain behaviors in several acute and chronic pain models in rodents. The present study was designed to ascertain whether KRM-II-81 and the structural analog MP-III-80 (3-ethyl-5-(8-ethynyl-6-(pyridin-2-yl)-4H-benzo[f]imidazo[1,5-a][1,4]diazepin-3-yl)-1,2,4-oxadiazole) would block chemotherapeutic agent paclitaxel-induced pain in male, C57BL/6 mice. Both compounds significantly inhibited pain behaviors evoked by cold and tactile stimulation in paclitaxel-treated mice as did the neuropathic pain drug gabapentin. Subchronic dosing for 22 days with KRM-II-81 and MP-III-80 demonstrated enduring analgesic efficacy without tolerance development, while the effects of gabapentin showed evidence of tolerance development. KRM-II-81 and MP-III-80 also decreased marble-burying behavior in this mouse strain as did the anxiolytic drug chlordiazepoxide. In contrast to KRM-II-81 and MP-III-80, chlordiazepoxide had motor-impairing effects at anxiolytic-like doses. The data add to the literature documenting that these selective potentiators of α2/3-containing GABAA receptors are effective in a host of animal models used to detect novel analgesic drugs. The anxiolytic-like efficacy of these compounds fits well with the comorbidity of anxiety in patients with chronic pain and cancer.


Assuntos
Ansiolíticos/farmacologia , Antineoplásicos/efeitos adversos , Agonistas de Receptores de GABA-A/farmacologia , Hiperalgesia/prevenção & controle , Oxazóis/farmacologia , Receptores de GABA-A/efeitos dos fármacos , Doença Aguda , Animais , Doença Crônica , Sinergismo Farmacológico , Tolerância a Medicamentos , Hiperalgesia/induzido quimicamente , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Neuralgia/induzido quimicamente , Neuralgia/prevenção & controle
3.
Pharmacol Biochem Behav ; 180: 22-31, 2019 05.
Artigo em Inglês | MEDLINE | ID: mdl-30825491

RESUMO

Clinical evidence indicates that positive allosteric modulators (PAMs) of GABAA receptors have analgesic benefit in addition to efficacy in anxiety disorders. However, the utility of GABAA receptor PAMs as analgesics is compromised by the central nervous system side effects of non-selective potentiators. A selective potentiator of GABAA receptors associated with α2/3 subunits, KRM-II-81(5-(8-ethynyl-6-(pyridin-2-yl)-4H-benzo[f]imidazo[1,5-a][1,4]diazepin-3-yl)oxazole), has demonstrated anxiolytic, anticonvulsant, and antinociceptive effects in rodents with reduced motoric side effects. The present study evaluated the potential of KRM-II-81 as a novel analgesic. Oral administration of KRM-II-81 attenuated formalin-induced flinching; in contrast, diazepam was not active. KRM-II-81 attenuated nociceptive-associated behaviors engendered by chronic spinal nerve ligation (L5/L6). Diazepam decreased locomotion of rats at the dose tested in the formalin assay (10 mg/kg) whereas KRM-II-81 produced small decreases that were not dose-dependent (10-100 mg/kg). Plasma and brain levels of KRM-II-81 were used to demonstrate selectivity for α2/3- over α1-associated GABAA receptors and to define the degree of engagement of these receptors. Plasma and brain concentrations of KRM-II-81 were positively-associated with analgesic efficacy. GABA currents from isolated rat dorsal-root ganglion cultures were potentiated by KRM-II-81 with an ED50 of 32 nM. Measures of respiratory depression were reduced by alprazolam whereas KRM-II-81 was either inactive or produced effects with lower potency and efficacy. These findings add to the growing body of data supporting the idea that α2/3-selective GABAA receptor PAMs will have efficacy and tolerability as pain medications including those for neuropathic pain. Given their predicted anxiolytic effects, α2/3-selective GABAA receptor PAMs offer an additional inroad into the management of pain.


Assuntos
Analgésicos/farmacologia , Sinergismo Farmacológico , Formaldeído/farmacologia , Oxazóis/farmacologia , Medição da Dor , Receptores de GABA-A/metabolismo , Nervos Espinhais/cirurgia , Adjuvantes Anestésicos/farmacologia , Administração Oral , Alprazolam/administração & dosagem , Alprazolam/farmacologia , Analgésicos/administração & dosagem , Analgésicos/metabolismo , Analgésicos/uso terapêutico , Animais , Comportamento Animal/efeitos dos fármacos , Diazepam/farmacologia , Relação Dose-Resposta a Droga , Moduladores GABAérgicos/administração & dosagem , Moduladores GABAérgicos/farmacologia , Ligadura , Masculino , Neuralgia/tratamento farmacológico , Oxazóis/administração & dosagem , Oxazóis/metabolismo , Oxazóis/uso terapêutico , Ratos , Ratos Sprague-Dawley
4.
BMC Evol Biol ; 18(1): 193, 2018 12 14.
Artigo em Inglês | MEDLINE | ID: mdl-30547744

RESUMO

BACKGROUND: Obligate pollination mutualisms (OPMs) are specialized interactions in which female pollinators transport pollen between the male and female flowers of a single plant species and then lay eggs into those same flowers. The pollinator offspring hatch and feed upon some or all of the developing ovules pollinated by their mothers. Strong trait matching between plants and their pollinators in OPMs is expected to result in reciprocal partner specificity i.e., a single pollinator species using a single plant species and vice versa, and strict co-speciation. These issues have been studied extensively in figs and fig wasps, but little in the more recently discovered co-diversification of Epicephala moths and their Phyllanthaceae hosts. OPMs involving Epicephala moths are believed occur in approximately 500 species of Phyllanthaceae, making it the second largest OPM group after the Ficus radiation (> 750 species). In this study, we used a mixture of DNA barcoding, genital morphology and behavioral observations to determine the number of Epicephala moth species inhabiting the fruits of Breynia oblongifolia, their geographic distribution, pollinating behavior and phylogenetic relationships. RESULTS: We found that B. oblongifolia hosts two species of pollinator that co-occurred at all study sites, violating the assumption of reciprocal specificity. Male and female genital morphologies both differed considerably between the two moth species. In particular, females differed in the shape of their ovipositors, eggs and oviposition sites. Phylogenetic analyses indicated that the two Epicephala spp. on B. oblongifolia likely co-exist due to a host switch. In addition, we discovered that Breynia fruits are also often inhabited by a third moth, an undescribed species of Herpystis, which is a non-pollinating seed parasite. CONCLUSIONS: Our study reveals new complexity in interactions between Phyllantheae and Epicephala pollinators and highlights that host switching, co-speciation and non-pollinating seed parasites can shape species interactions in OPMs. Our finding that co-occurring Epicephala species have contrasting oviposition modes parallels other studies and suggests that such traits are important in Epicephala species coexistence.


Assuntos
Malpighiaceae/parasitologia , Parasitos/fisiologia , Polinização/fisiologia , Animais , Teorema de Bayes , Código de Barras de DNA Taxonômico , Feminino , Geografia , Masculino , Mariposas/anatomia & histologia , Mariposas/fisiologia , Mariposas/ultraestrutura , New South Wales , Ovário/citologia , Oviposição , Óvulo Vegetal/citologia , Parasitos/anatomia & histologia , Parasitos/ultraestrutura , Filogenia , Especificidade da Espécie
5.
Pharmacol Biochem Behav ; 170: 9-13, 2018 07.
Artigo em Inglês | MEDLINE | ID: mdl-29715490

RESUMO

Data from transgenic animals and novel pharmacological agents has realigned scientific scrutiny on the therapeutic potential of positive allosteric modulators (PAMs) of α2/3-containing GABAA receptors. Evidence for analgesic, anticonvulsant, and anxiolytic activity of α2/3-selective PAMs has been presented along with the clinical potential for a milder motor-impacting profile compared to non-selective GABAA receptor PAMs. A new series of α2/3-selective PAMs was recently introduced which has anxiolytic and anticonvulsant activity in rodent models. These molecules also produce efficacy against pain in multiple animal models. Additionally, co-morbid states of depression are prevalent among patients with pain and patients with anxiety. Compounds were shown to be selective for α2 and α3 constructs over α1 (except KRM-II-82), α4, α5, and α6 proteins in electrophysiological assays in transfected HEK-293T cells. Utilizing the forced-swim assay in mice that detects conventional and novel antidepressant drugs, we demonstrate for the first time that α2/3-selective PAMs are active in the forced-swim assay at anxiolytic-producing doses. In contrast, activity in a related model, the tail-suspension test, was not observed. Diazepam was not active in the forced-swim assay when given alone but produced an antidepressant-like effect in mice when given in conjunction with the α1-preferring antagonist, ß-CCT, that attenuated the motor-impairing effects of diazepam. We conclude that these α2/3-selective PAMs deserve further scrutiny for their potential treatment of major depressive disorder. If effective, such a mechanism could add a beneficial antidepressant component to the anxiolytic, analgesic, and anticonvulsant spectrum of effects of these compounds.


Assuntos
Antidepressivos/farmacologia , Receptores de GABA-A/efeitos dos fármacos , Regulação Alostérica , Animais , Transtorno Depressivo Maior/tratamento farmacológico , Diazepam/farmacologia , Células HEK293 , Elevação dos Membros Posteriores , Humanos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Atividade Motora/efeitos dos fármacos , Natação
6.
Neuropharmacology ; 137: 332-343, 2018 07 15.
Artigo em Inglês | MEDLINE | ID: mdl-29778948

RESUMO

HZ-166 has previously been characterized as an α2,3-selective GABAA receptor modulator with anticonvulsant, anxiolytic, and anti-nociceptive properties but reduced motor effects. We discovered a series of ester bioisosteres with reduced metabolic liabilities, leading to improved efficacy as anxiolytic-like compounds in rats. In the present study, we evaluated the anticonvulsant effects KRM-II-81 across several rodent models. In some models we also evaluated key structural analogs. KRM-II-81 suppressed hyper-excitation in a network of cultured cortical neurons without affecting the basal neuronal activity. KRM-II-81 was active against electroshock-induced convulsions in mice, pentylenetetrazole (PTZ)-induced convulsions in rats, elevations in PTZ-seizure thresholds, and amygdala-kindled seizures in rats with efficacies greater than that of diazepam. KRM-II-81 was also active in the 6 Hz seizure model in mice. Structural analogs of KRM-II-81 but not the ester, HZ-166, were active in all models in which they were evaluated. We further evaluated KRM-II-81 in human cortical epileptic tissue where it was found to significantly-attenuate picrotoxin- and AP-4-induced increases in firing rate across an electrode array. These molecules generally had a wider margin of separation in potencies to produce anticonvulsant effects vs. motor impairment on an inverted screen test than did diazepam. Ester bioisosters of HZ-166 are thus presented as novel agents for the potential treatment of epilepsy acting via selective positive allosteric amplification of GABAA signaling through α2/α3-containing GABA receptors. The in vivo data from the present study can serve as a guide to dosing parameters that predict engagement of central GABAA receptors.


Assuntos
Anticonvulsivantes/farmacologia , Agonistas de Receptores de GABA-A/farmacologia , Oxazóis/farmacologia , Convulsões/tratamento farmacológico , Potenciais de Ação/efeitos dos fármacos , Animais , Anticonvulsivantes/química , Anticonvulsivantes/farmacocinética , Benzodiazepinas/química , Benzodiazepinas/farmacocinética , Benzodiazepinas/farmacologia , Disponibilidade Biológica , Criança , Diazepam/farmacologia , Modelos Animais de Doenças , Epilepsia Resistente a Medicamentos/tratamento farmacológico , Epilepsia Resistente a Medicamentos/fisiopatologia , Feminino , Agonistas de Receptores de GABA-A/química , Agonistas de Receptores de GABA-A/farmacocinética , Humanos , Imidazóis/química , Imidazóis/farmacocinética , Imidazóis/farmacologia , Masculino , Camundongos , Oxazóis/química , Oxazóis/farmacocinética , Distribuição Aleatória , Ratos Sprague-Dawley , Convulsões/fisiopatologia , Técnicas de Cultura de Tecidos
7.
Mol Psychiatry ; 23(2): 384-391, 2018 02.
Artigo em Inglês | MEDLINE | ID: mdl-28322281

RESUMO

Current pharmacotherapies for depression exhibit slow onset, side effects and limited efficacy. Therefore, identification of novel fast-onset antidepressants is desirable. GLO1 is a ubiquitous cellular enzyme responsible for the detoxification of the glycolytic byproduct methylglyoxal (MG). We have previously shown that MG is a competitive partial agonist at GABA-A receptors. We examined the effects of genetic and pharmacological inhibition of GLO1 in two antidepressant assay models: the tail suspension test (TST) and the forced swim test (FST). We also examined the effects of GLO1 inhibition in three models of antidepressant onset: the chronic FST (cFST), chronic mild stress (CMS) paradigm and olfactory bulbectomy (OBX). Genetic knockdown of Glo1 or pharmacological inhibition using two structurally distinct GLO1 inhibitors (S-bromobenzylglutathione cyclopentyl diester (pBBG) or methyl-gerfelin (MeGFN)) reduced immobility in the TST and acute FST. Both GLO1 inhibitors also reduced immobility in the cFST after 5 days of treatment. In contrast, the serotonin reuptake inhibitor fluoxetine (FLX) reduced immobility after 14, but not 5 days of treatment. Furthermore, 5 days of treatment with either GLO1 inhibitor blocked the depression-like effects induced by CMS on the FST and coat state, and attenuated OBX-induced locomotor hyperactivity. Finally, 5 days of treatment with a GLO1 inhibitor (pBBG), but not FLX, induced molecular markers of the antidepressant response including brain-derived neurotrophic factor (BDNF) induction and increased phosphorylated cyclic-AMP response-binding protein (pCREB) to CREB ratio in the hippocampus and medial prefrontal cortex (mPFC). Our findings indicate that GLO1 inhibitors may provide a novel and fast-acting pharmacotherapy for depression.


Assuntos
Lactoilglutationa Liase/antagonistas & inibidores , Lactoilglutationa Liase/fisiologia , Aldeído Pirúvico/farmacologia , Animais , Antidepressivos/farmacologia , Depressão/tratamento farmacológico , Depressão/metabolismo , Transtorno Depressivo/tratamento farmacológico , Transtorno Depressivo/metabolismo , Feminino , GABAérgicos/farmacologia , Elevação dos Membros Posteriores , Hipocampo/efeitos dos fármacos , Lactoilglutationa Liase/genética , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Córtex Pré-Frontal/efeitos dos fármacos , Natação
8.
Mol Ecol ; 26(19): 5358, 2017 10.
Artigo em Inglês | MEDLINE | ID: mdl-29052950
9.
Pharmacol Biochem Behav ; 157: 35-40, 2017 06.
Artigo em Inglês | MEDLINE | ID: mdl-28442369

RESUMO

Positive allosteric modulators of GABAA receptors transduce a host of beneficial effects including anxiolytic actions. We have recently shown that bioavailability and anxiolytic-like activity can be improved by eliminating the ester functionality in imidazo[1,5-a][1,4]diazepines. In the present series of experiments, we further substantiate the value of heterocyle replacement of the ester for potential treatment of anxiety. None of three esters was active in a Vogel conflict test in rats that detects anxiolytic drugs like diazepam. Compounds 7 and 8, ester bioisosters, were selective for alpha 2 and 3 over alpha 1-containing GABAA receptors but also had modest efficacy at GABAA alpha 5-containing receptors. Compound 7 was efficacious and potent in this anxiolytic-detecting assay without affecting non-punished responding. The efficacies of the esters and of compound 7 were predicted from their efficacies as anticonvulsants against the GABAA antagonist pentylenetetrazole (PTZ). In contrast, the related structural analog, compound 8, did not produce anxiolytic-like effects in rats despite anticonvulsant efficacy. These data thus support the following conclusions: 1) ancillary pharmacological actions of compound 8 might be responsible for its lack of anxiolytic-like efficacy despite its efficacy as an anticonvulsant 2) esters of imidazo[1,5-a][1,4]diazepines do not demonstrate anxiolytic-like effects in rats due to their low bioavailability and 3) replacement of the ester function with suitable heterocycles markedly improves bioavailability and engenders molecules with the opportunity to have potent and efficacious effects in vivo that correspond to human anxiolytic actions.


Assuntos
Ansiolíticos/uso terapêutico , Ansiedade/tratamento farmacológico , Benzodiazepinas/uso terapêutico , Agonistas de Receptores de GABA-A/uso terapêutico , Receptores de GABA-A/fisiologia , Animais , Ansiolíticos/química , Ansiedade/psicologia , Benzodiazepinas/química , Relação Dose-Resposta a Droga , Avaliação Pré-Clínica de Medicamentos/métodos , Agonistas de Receptores de GABA-A/química , Células HEK293 , Humanos , Masculino , Ratos , Ratos Sprague-Dawley
10.
Heredity (Edinb) ; 118(5): 486-490, 2017 05.
Artigo em Inglês | MEDLINE | ID: mdl-28074845

RESUMO

Molecular tools increasingly reveal cryptic lineages and species that were previously unnoticed by traditional taxonomy. The discovery of cryptic species in sympatry prompts the question of how they coexist in the apparent absence of ecological divergence. However, this assumes first that the molecular taxonomy used to identify cryptic lineages delimits species boundaries accurately. This issue is important, because many diversity studies rely heavily or solely on data from mitochondrial DNA sequences for species delimitation, and several factors may lead to poor identification of species boundaries. We used a multilocus population genetics approach to show that three mtDNA-defined cryptic lineages of the fig wasp Pleistodontes imperialis Saunders, which pollinate Port Jackson figs (Ficus rubiginosa) in north-eastern Australia, represent reproductively isolated species. These species coexist locally, with about 13% of figs (where mating occurs) containing wasps from two or three species. However, there was no evidence for gene flow between them. Confirmed cases of coexisting cryptic species provide excellent opportunities for future studies of the ecological and evolutionary forces shaping both species coexistence and fig/pollinator coevolution.


Assuntos
Ficus , Genética Populacional , Isolamento Reprodutivo , Simpatria , Vespas/classificação , Animais , Austrália , DNA Mitocondrial/genética , Fluxo Gênico , Marcadores Genéticos , Genótipo , Hibridização Genética , Repetições de Microssatélites , Filogenia , Polinização , Árvores , Vespas/genética
11.
Mol Ecol ; 26(3): 937-950, 2017 02.
Artigo em Inglês | MEDLINE | ID: mdl-28026893

RESUMO

A key debate in ecology centres on the relative importance of niche and neutral processes in determining patterns of community assembly with particular focus on whether ecologically similar species with similar functional traits are able to coexist. Meanwhile, molecular studies are increasingly revealing morphologically indistinguishable cryptic species with presumably similar ecological roles. Determining the geographic distribution of such cryptic species provides opportunities to contrast predictions of niche vs. neutral models. Discovery of sympatric cryptic species increases alpha diversity and supports neutral models, while documentation of allopatric/parapatric cryptic species increases beta diversity and supports niche models. We tested these predictions using morphological and molecular data, coupled with environmental niche modelling analyses, of a fig wasp community along its 2700-km latitudinal range. Molecular methods increased previous species diversity estimates from eight to eleven species, revealing morphologically cryptic species in each of the four wasp genera studied. Congeneric species pairs that were differentiated by a key morphological functional trait (ovipositor length) coexisted sympatrically over large areas. In contrast, morphologically similar species, with similar ovipositor lengths, typically showed parapatric ranges with very little overlap. Despite parapatric ranges, environmental niche models of cryptic congeneric pairs indicate large regions of potential sympatry, suggesting that competitive processes are important in determining the distributions of ecologically similar species. Niche processes appear to structure this insect community, and cryptic diversity may typically contribute mostly to beta rather than alpha diversity.


Assuntos
Ecossistema , Simpatria , Vespas/classificação , Animais , Ficus
12.
Adm Policy Ment Health ; 43(6): 957-977, 2016 11.
Artigo em Inglês | MEDLINE | ID: mdl-27474040

RESUMO

Since 2006, the Veterans Health Administration (VHA) has instituted policy changes and training programs to support system-wide implementation of two evidence-based psychotherapies (EBPs) for posttraumatic stress disorder (PTSD). To assess lessons learned from this unprecedented effort, we used PubMed and the PILOTS databases and networking with researchers to identify 32 reports on contextual influences on implementation or sustainment of EBPs for PTSD in VHA settings. Findings were initially organized using the exploration, planning, implementation, and sustainment framework (EPIS; Aarons et al. in Adm Policy Ment Health Health Serv Res 38:4-23, 2011). Results that could not be adequately captured within the EPIS framework, such as implementation outcomes and adopter beliefs about the innovation, were coded using constructs from the reach, effectiveness, adoption, implementation, maintenance (RE-AIM) framework (Glasgow et al. in Am J Public Health 89:1322-1327, 1999) and Consolidated Framework for Implementation Research (CFIR; Damschroder et al. in Implement Sci 4(1):50, 2009). We highlight key areas of progress in implementation, identify continuing challenges and research questions, and discuss implications for future efforts to promote EBPs in large health care systems.


Assuntos
Prática Clínica Baseada em Evidências , Psicoterapia , Transtornos de Estresse Pós-Traumáticos/terapia , Difusão de Inovações , Humanos , Estados Unidos , United States Department of Veterans Affairs
13.
J Clin Pharm Ther ; 40(5): 545-549, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26177778

RESUMO

WHAT IS KNOWN AND OBJECTIVES: Some studies, howbeit with conflicting reports, have suggested that consumption of honey has a potential to modulate drug metabolizing enzymes which may result in a honey-drug interaction. Numerous studies have established that honey varies in composition, influenced by the dominant floral, processing and environmental factors. Thus, variation in honey composition may be a contributing factor to the controversial results obtained. No previous drug interaction study has been carried out with any honey from Africa. CYP 3A4 is an important enzyme in drug metabolism studies as it is involved in the metabolism of over 50% of drugs in clinical use and quinine remains very relevant in malaria treatment in the tropics, and we therefore determined whether there is potential drug interaction between a Nigerian honey and quinine, a drug whose metabolism to 3-hydroxyquinine is mediated majorly by CYP3A4. METHODS: In a three-phase randomized crossover study with a washout period of 2 weeks between each treatment phase, ten (10) healthy volunteers received quinine sulphate tablet (600 mg single dose) alone (phase 1) or after administration of 10 ml of honey (Phase 2) and 20 mL of honey (Phase 3) twice daily for seven (7) days. Blood samples were collected at the 16th hour post-quinine administration in each phase, and quinine and its major metabolite, 3-hydroxyquinine, were analysed using a validated HPLC method. RESULTS: After scheduled doses of honey, the mean metabolic ratios of quinine (3-hydroxyquinine/quinine) increased by 24·4% (with 10 mL of honey) and reduced by 23·9% (with 20 mL of honey) when compared to baseline. These magnitudes of alteration in the mean metabolic ratios were not significant (P > 0·05; Friedman test). The geometric mean (95% CI) for the metabolic ratio of quinine before and after honey intake at the two dose levels studied was 0·82 (0·54, 1·23) and 1·29 (0·96, 1·72), respectively, and were also not significant (P = 0·296 and 0·081 respectively; Student's t-test). WHAT IS NEW AND CONCLUSION: This is a pioneer study on the effect of Nigerian/African honey on quinine metabolism. The findings indicated that low and high doses of honey did not significantly affect metabolism of quinine to 3-hydroxyquinine. This suggests that CYP3A4 activity is not significantly altered following low or high dose of honey, as CYP3A4 has been reported to be responsible for the conversion of quinine to 3-hydroxyquinine. In conclusion, the outcome of this study suggests that there may be no potential significant metabolic interaction between Nigerian honey and quinine administration.

14.
Phys Rev Lett ; 106(16): 162502, 2011 Apr 22.
Artigo em Inglês | MEDLINE | ID: mdl-21599362

RESUMO

Absolute cross sections have been determined following single neutron knockout reactions from 10Be and 10C at intermediate energy. Nucleon density distributions and bound-state wave function overlaps obtained from both variational Monte Carlo (VMC) and no core shell model (NCSM) ab initio calculations have been incorporated into the theoretical description of knockout reactions. Comparison to experimental cross sections demonstrates that the VMC approach, with the inclusion of 3-body forces, provides the best overall agreement while the NCSM and conventional shell-model calculations both overpredict the cross sections by 20% to 30% for 10Be and by 40% to 50% for 10C, respectively. This study gains new insight into the importance of 3-body forces and continuum effects in light nuclei and provides a sensitive technique to assess the accuracy of ab initio calculations for describing these effects.

15.
Eur J Dent Educ ; 13(3): 135-41, 2009 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-19630931

RESUMO

Recent legislative changes, that affect all healthcare practitioners in New Zealand, have resulted in mandatory audits of practitioners who are now required to provide evidence of competence and continued professional development in the form of a professional portfolio. These changes were the motivation for our development of an electronic portfolio (ePortfolio) suitable for both undergraduate and life-long learning. Bachelor of Oral Health (BOH) students, studying to qualify as Dental Hygienists and Dental Therapists, and BOH teaching staff (who held registrations in Dental Hygiene, Dental Therapy and Dentistry) trialled the use of a personal ePortfolio for advancing their academic and professional development. The ePortfolio enables BOH students to collect evidence of their achievements and personal reflections throughout their 3 years of undergraduate study, culminating in registration and the award of an Annual Practising Certificate (APC). The ePortfolio was designed to allow users to store information and then select appropriate material to be displayed or published, thus assisting health practitioners to present high-quality evidence of their participation and achievements, and to meet the professional requirements for their APC.


Assuntos
Certificação , Competência Clínica/normas , Documentação/métodos , Educação Continuada em Odontologia , Aprendizagem , Computadores , Currículo , Avaliação Educacional , Humanos , Nova Zelândia , Higiene Bucal/educação
16.
Phys Rev Lett ; 102(18): 182502, 2009 May 08.
Artigo em Inglês | MEDLINE | ID: mdl-19518865

RESUMO

We report on the first in-beam gamma-ray spectroscopy study of the very neutron-rich nucleus 46S. The N=30 isotones 46S and 48Ar were produced in a novel way in two steps that both necessarily involve nucleon exchange and neutron pickup reactions 9Be(48Ca,48K)X followed by 9Be(48K,48Ar+gamma)X at 85.7 MeV/u midtarget energy and 9Be(48Ca,46Cl)X followed by 9Be(46Cl,46S+gamma)X at 87.0 MeV/u midtarget energy, respectively. The results are compared to large-scale shell-model calculations in the sd-pf shell using the SDPF-NR effective interaction and Z-dependent modifications.

17.
J Evol Biol ; 21(6): 1597-608, 2008 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-18764883

RESUMO

Ants are a diverse and abundant insect group that form mutualistic associations with a number of different organisms from fungi to insects and plants. Here, we use a phylogenetic approach to identify ecological factors that explain macroevolutionary trends in the mutualism between ants and honeydew-producing Homoptera. We also consider association between ant-Homoptera, ant-fungi and ant-plant mutualisms. Homoptera-tending ants are more likely to be forest dwelling, polygynous, ecologically dominant and arboreal nesting with large colonies of 10(4)-10(5) individuals. Mutualistic ants (including those that garden fungi and inhabit ant-plants) are found in under half of the formicid subfamilies. At the genus level, however, we find a negative association between ant-Homoptera and ant-fungi mutualisms, whereas there is a positive association between ant-Homoptera and ant-plant mutualisms. We suggest that species can only specialize in multiple mutualisms simultaneously when there is no trade-off in requirements from the different partners and no redundancy of rewards.


Assuntos
Formigas/fisiologia , Evolução Biológica , Fungos/fisiologia , Insetos/fisiologia , Simbiose/fisiologia , Animais , Ecossistema , Filogenia , Fenômenos Fisiológicos Vegetais
18.
Insect Mol Biol ; 16(6): 743-52, 2007 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-18093003

RESUMO

Mariner transposable elements are widespread and diverse in insects. We screened 10 species of fig wasps (Hymenoptera: Agaonidae) for mariner elements. All 10 species harbour a large diversity of mariner elements, most of which have interrupted reading frames in the transposase gene region, suggesting that they are inactive and ancient. We sequenced two full-length mariner elements and found evidence to suggest that they are inserted in the genome at a conserved region shared by other hymenopteran taxa. The association between mariner elements and fig wasps is old and dominated by vertical transmission, suggesting that these 'selfish genetic elements' have evolved to impart only very low costs to their hosts.


Assuntos
Elementos de DNA Transponíveis/genética , Proteínas de Ligação a DNA/genética , Transposases/genética , Vespas/genética , Sequência de Aminoácidos , Animais , Sequência de Bases , DNA/genética , Evolução Molecular , Feminino , Genes de Insetos , Masculino , Dados de Sequência Molecular , Filogenia , Homologia de Sequência do Ácido Nucleico , Especificidade da Espécie
19.
Curr Med Chem ; 14(26): 2755-75, 2007.
Artigo em Inglês | MEDLINE | ID: mdl-18045122

RESUMO

A successful unified pharmacophore/receptor model which has guided the synthesis of subtype selective compounds is reviewed in light of recent developments both in ligand synthesis and structural studies of the binding site itself. The evaluation of experimental data in combination with a comparative model of the alpha1beta2gamma2 GABA(A) receptor leads to an orientation of the pharmacophore model within the Bz BS. Results not only are important for the rational design of selective ligands, but also for the identification and evaluation of possible roles which specific residues may have within the benzodiazepine binding pocket.


Assuntos
Benzodiazepinas/metabolismo , Antagonistas GABAérgicos/metabolismo , Moduladores GABAérgicos/metabolismo , Receptores de GABA-A/metabolismo , Ácido gama-Aminobutírico/metabolismo , Benzodiazepinas/química , Sítios de Ligação , Desenho de Fármacos , Flavonoides/química , Flavonoides/metabolismo , Antagonistas GABAérgicos/química , Moduladores GABAérgicos/química , Ligantes , Modelos Biológicos , Estrutura Molecular , Receptores de GABA-A/química , Estereoisomerismo , Ácido gama-Aminobutírico/química
20.
Phys Rev Lett ; 99(16): 162501, 2007 Oct 19.
Artigo em Inglês | MEDLINE | ID: mdl-17995242

RESUMO

Rare isotope beams of neutron-deficient 106,108,110Sn from the fragmentation of 124Xe were employed in an intermediate-energy Coulomb excitation experiment. The measured B(E2,0(1)(+)-->2(1)(+)) values for 108Sn and 110Sn and the results obtained for the 106Sn show that the transition strengths for these nuclei are larger than predicted by current state-of-the-art shell-model calculations. This discrepancy might be explained by contributions of the protons from within the Z = 50 shell to the structure of low-energy excited states in this region.

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