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1.
Insects ; 14(10)2023 Oct 04.
Artículo en Inglés | MEDLINE | ID: mdl-37887813

RESUMEN

Exotic tephritid incursions are of high concern to Australia's biosecurity and its horticultural industries. It is vital that Australia remains ready to respond to incursions as they arise, as an incursion of tephritid fruit fly species will result in significant economic losses. In this review, we compared Australian incursion management strategies for fruit flies with global management strategies and identified possible areas where improvements could be made in an Australian context. Overall, Australia has a good understanding of the main tephritid threats, of which Bactrocera species from across the Torres Strait (northern Australia) are of most concern. Effective tools for tephritid detection and early warning surveillance at points of entry are in place at ports and in horticultural areas Australia-wide and provide the basis for initiating biosecurity responses in the event of an incursion. Area-wide control measures used in successful eradication attempts globally are available for use in Australia. However, a specific tephritid emergency response plan identifying suitable response measures and control options for species of concern is not yet available. We have identified that Australia has the policies and management tools available to respond to an exotic tephritid incursion, but the speed at which this could be accomplished would be greatly improved by the development of species-specific emergency response plans.

2.
Rapid Commun Mass Spectrom ; 36(8): e9261, 2022 Apr 30.
Artículo en Inglés | MEDLINE | ID: mdl-35088453

RESUMEN

RATIONALE: Nitrosamines are a class of mutagenic substances that can display high carcinogenic potential. New chemical entities may have the potential to form unique nitrosamines specific to the drug substance. It is therefore essential to understand the gas-phase fragmentation behavior of nitrosamine compounds to enable the development of analytical methods to characterize novel nitrosamine compounds. METHODS: The gas-phase fragmentation behavior of eight model nitrosamine compounds representing the common substructures seen in many small molecule pharmaceutical compounds was studied with positive electrospray ionization tandem mass spectrometry (ESI-MS/MS). The fragmentation patterns of these compounds under various collision parameters available in commercially available mass spectrometers were studied. RESULTS: Protonated nitrosamine compounds produced diagnostic fragment ions upon MS/MS. Three primary structure-dependent fragmentation pathways were observed. The first pathway involves the loss of 30 Da which corresponds to the loss of the NO radical from the protonated nitrosamine compound (Group 1). The second and third fragmentation pathways, which have not been reported for nitrosamine compounds, proceed via the loss of H2 O from the protonated nitrosamine compound (Group 2), and elimination and a loss of 46 Da (loss of NH2 NO) from the nitrosamine compound (Group 3). CONCLUSIONS: Results presented in this work provide an overview of the gas-phase fragmentation patterns of nitrosamine compounds and may be useful in identifying novel nitrosamine compounds in complex matrices.


Asunto(s)
Nitrosaminas , Espectrometría de Masas en Tándem , Iones , Espectrometría de Masa por Ionización de Electrospray/métodos , Espectrometría de Masas en Tándem/métodos
3.
Int J Eat Disord ; 54(4): 615-620, 2021 04.
Artículo en Inglés | MEDLINE | ID: mdl-33462885

RESUMEN

OBJECTIVE: While there is evidence to support the use of group dialectical behavior therapy (DBT) in the treatment of binge-eating disorder (BED), treatment is relatively long compared with other evidence-based treatments. This study explored the effectiveness of brief DBT groups for BED, delivered in a routine community setting. METHOD: Eighty-four adults with BED entered 10-week DBT group treatment in a community eating disorders service. In total, 12 groups were conducted. Patients completed measures of eating disorder pathology, anxiety, depression, and emotional eating at the start and end of treatment, and at 1-month follow-up. Frequency of weekly binges was recorded. RESULTS: Outcomes were similar to those of longer versions of DBT, with an attrition rate of 26%, and significant reductions in eating disorder psychopathology and emotional eating by the end of treatment and at follow-up. Over 50% of patients were abstinent from binge eating by Session 4. DISCUSSION: Group DBT delivered in a 10-session format is clinically equivalent to longer versions of the same treatment. Future research is required to explore patterns of change and to demonstrate replicability under controlled conditions, but these findings are promising for the efficient delivery of effective treatment and reducing waiting times.


Asunto(s)
Trastorno por Atracón , Bulimia , Terapia Conductual Dialéctica , Adulto , Terapia Conductista , Trastorno por Atracón/terapia , Emociones , Humanos , Resultado del Tratamiento
4.
J Therm Biol ; 93: 102690, 2020 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-33077113

RESUMEN

Much interest exists in the extent to which constant versus fluctuating temperatures affect thermal performance traits and their phenotypic plasticity. Theory suggests that effects should vary with temperature, being especially pronounced at more extreme low (because of thermal respite) and high (because of Jensen's inequality) temperatures. Here we tested this idea by examining the effects of constant temperatures (10 to 30 °C in 5 °C increments) and fluctuating temperatures (means equal to the constant temperatures, but with fluctuations of ±5 °C) temperatures on the adult (F2) phenotypic plasticity of three thermal performance traits - critical thermal minimum (CTmin), critical thermal maximum (CTmax), and upper lethal temperature (ULT50) in ten species of springtails (Collembola) from three families (Isotomidae 7 spp.; Entomobryidae 2 spp.; Onychiuridae 1 sp.). The lowest mean CTmin value recorded here was -3.56 ± 1.0 °C for Paristoma notabilis and the highest mean CTmax was 43.1 ± 0.8 °C for Hemisotoma thermophila. The Acclimation Response Ratio for CTmin was on average 0.12 °C/°C (range: 0.04 to 0.21 °C/°C), but was much lower for CTmax (mean: 0.017 °C/°C, range: -0.015 to 0.047 °C/°C) and lower also for ULT50 (mean: 0.05 °C/°C, range: -0.007 to 0.14 °C/°C). Fluctuating versus constant temperatures typically had little effect on adult phenotypic plasticity, with effect sizes either no different from zero, or inconsistent in the direction of difference. Previous work assessing adult phenotypic plasticity of these thermal performance traits across a range of constant temperatures can thus be applied to a broader range of circumstances in springtails.


Asunto(s)
Artrópodos/fisiología , Termotolerancia , Animales , Artrópodos/clasificación , Suelo
5.
Int J Eat Disord ; 52(5): 530-537, 2019 05.
Artículo en Inglés | MEDLINE | ID: mdl-30741438

RESUMEN

OBJECTIVE: Although it is important to analyze the effectiveness of new therapies, it is also necessary to consider how patients experience them. This is particularly important if we are to maximize treatment acceptability and reduce attrition. This study examined patient experiences of a new 10-session cognitive-behavioral therapy (CBT-T), using a qualitative approach. METHOD: The sample was 17 patients with a diagnosis of bulimia nervosa who had received CBT-T (including treatment completers and non-completers) within the previous 2 years. Sample size was determined by saturation of the emergent themes. Responses were analyzed using a six-step thematic analysis process. RESULTS: Rated acceptability and effectiveness of CBT-T were high. Five themes emerged, with subthemes. The key elements of patient experience of the therapy were: the therapeutic relationship; the nature of the therapy; its challenging but beneficial aspects; ending therapy; and the overall experience of CBT-T (including comparison with other therapies). DISCUSSION: The findings build on the effectiveness research for CBT-T, suggesting that it is an acceptable therapy that addresses many of the same themes that matter to patients as other therapies. The findings show that patients were positive about CBT-T relative to other therapies, and offer suggestions as to how CBT-T might be delivered to emphasize the importance of the time-limited nature of the therapy.


Asunto(s)
Terapia Cognitivo-Conductual/métodos , Trastornos de Alimentación y de la Ingestión de Alimentos/terapia , Adulto , Femenino , Humanos , Investigación Cualitativa , Resultado del Tratamiento
6.
Sci Rep ; 5: 11957, 2015 Jul 08.
Artículo en Inglés | MEDLINE | ID: mdl-26153104

RESUMEN

Although significant progress has been made using insect taxa as model organisms, non-tracheated terrestrial arthropods, such as Collembola, are underrepresented as model species. This underrepresentation reflects the difficulty in maintaining populations of specialist Collembola species in the laboratory. Until now, no species from the family Neanuridae have been successfully reared. Here we use controlled growth experiments to provide explicit evidence that the species Neanura muscorum can be raised under laboratory conditions when its diet is supplemented with slime mould. Significant gains in growth were observed in Collembola given slime mould rather than a standard diet of algae-covered bark. These benefits are further highlighted by the reproductive success of the experimental group and persistence of laboratory breeding stocks of this species and others in the family. The necessity for slime mould in the diet is attributed to the 'suctorial' mouthpart morphology characteristic of the Neanuridae. Maintaining laboratory populations of neanurid Collembola species will facilitate their use as model organisms, paving the way for studies that will broaden the current understanding of the environmental physiology of arthropods.


Asunto(s)
Artrópodos/fisiología , Reproducción/fisiología , Animales , Animales de Laboratorio , Artrópodos/crecimiento & desarrollo , Dieta
7.
Proc Biol Sci ; 282(1809): 20150429, 2015 Jun 22.
Artículo en Inglés | MEDLINE | ID: mdl-26019160

RESUMEN

The evolutionary maintenance of same-sex sexual behaviour (SSB) has received increasing attention because it is perceived to be an evolutionary paradox. The genetic basis of SSB is almost wholly unknown in non-human animals, though this is key to understanding its persistence. Recent theoretical work has yielded broadly applicable predictions centred on two genetic models for SSB: overdominance and sexual antagonism. Using Drosophila melanogaster, we assayed natural genetic variation for male SSB and empirically tested predictions about the mode of inheritance and fitness consequences of alleles influencing its expression. We screened 50 inbred lines derived from a wild population for male-male courtship and copulation behaviour, and examined crosses between the lines for evidence of overdominance and antagonistic fecundity selection. Consistent variation among lines revealed heritable genetic variation for SSB, but the nature of the genetic variation was complex. Phenotypic and fitness variation was consistent with expectations under overdominance, although predictions of the sexual antagonism model were also supported. We found an unexpected and strong paternal effect on the expression of SSB, suggesting possible Y-linkage of the trait. Our results inform evolutionary genetic mechanisms that might maintain low but persistently observed levels of male SSB in D. melanogaster, but highlight a need for broader taxonomic representation in studies of its evolutionary causes.


Asunto(s)
Evolución Biológica , Drosophila melanogaster/fisiología , Variación Genética , Modelos Genéticos , Conducta Sexual Animal , Animales , Drosophila melanogaster/genética , Femenino , Fertilidad , Aptitud Genética , Masculino
8.
Evolution ; 68(7): 1871-82, 2014 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-24627971

RESUMEN

Indirect genetic effects (IGEs) occur when genes expressed in one individual alter the phenotype of an interacting partner. IGEs can dramatically affect the expression and evolution of social traits. However, the interacting phenotype(s) through which they are transmitted are often unknown, or cryptic, and their detection would enhance our ability to accurately predict evolutionary change. To illustrate this challenge and possible solutions to it, we assayed male leg-tapping behavior using inbred lines of Drosophila melanogaster paired with a common focal male strain. The expression of tapping in focal males was dependent on the genotype of their interacting partner, but this strong IGE was cryptic. Using a multiple-regression approach, we identified male startle response as a candidate interacting phenotype: the longer it took interacting males to settle after being startled, the less focal males tapped them. A genome-wide association analysis identified approximately a dozen candidate protein-coding genes potentially underlying the IGE, of which the most significant was slowpoke. Our methodological framework provides information about candidate phenotypes and candidate single-nucleotide polymorphisms that underpin a strong yet cryptic IGE. We discuss how this approach can facilitate the detection of cryptic IGEs contributing to unusual evolutionary dynamics in other study systems.


Asunto(s)
Drosophila melanogaster/genética , Evolución Molecular , Conducta Social , Animales , Proteínas de Drosophila/genética , Canales de Potasio de Gran Conductancia Activados por el Calcio/genética , Masculino , Fenotipo , Polimorfismo de Nucleótido Simple , Selección Genética
9.
ACS Macro Lett ; 2(10): 845-848, 2013 Oct 15.
Artículo en Inglés | MEDLINE | ID: mdl-35607001

RESUMEN

While amphiphilic block copolymers have demonstrated their utility for a range of practical applications, the behavior of cyclic block copolymers remains largely unexplored due to limited synthetic access. To investigate their micelle formation, biocompatible cyclic amphiphilic poly(ethylene glycol)-polycaprolactone, c-(PEG-PCL), was synthesized by a combination of ring-opening polymerization (ROP) and click chemistry. In addition, exactly analogous linear block copolymers have been prepared as a control sample to elucidate the role of polymer architecture in their self-assembly and acid-catalyzed degradation.

10.
Chem Commun (Camb) ; 47(32): 9036-8, 2011 Aug 28.
Artículo en Inglés | MEDLINE | ID: mdl-21603694

RESUMEN

The surface modification of deep-cavity cavitands has been demonstrated by using the azide-alkyne "click" coupling to attach dendritic macromolecules or linear polymers onto their periphery. The resulting set of macromolecular cavitands exhibited tuneable solubility yet retained the ability to encapsulate guest molecules.


Asunto(s)
Alquinos/química , Azidas/química , Química Clic/métodos , Éteres Cíclicos/química , Resorcinoles/química , Solubilidad , Propiedades de Superficie
11.
J Mass Spectrom ; 45(6): 587-611, 2010 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-20527028

RESUMEN

Recent advances in the resolving power of matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS) enable the detailed characterization of linear homopolymers, and in particular provide invaluable data for the determination of their end-group functionalities. With the growing importance of macromolecular coupling reactions in building complex polymer architectures, the ability to accurately monitor end-group transformations is becoming increasingly important for synthetic polymer chemists. This tutorial demonstrates the application of MALDI-TOF MS in determining both end-group functionalities and their transformations for linear homopolymers. Examples of both polycaprolactone and polystyrene are examined, and the strengths and weaknesses of various approaches to data analysis are given.


Asunto(s)
Polímeros/química , Espectrometría de Masa por Láser de Matriz Asistida de Ionización Desorción/métodos , Calibración , Modelos Lineales , Poliésteres/química , Poliestirenos/química
13.
PLoS One ; 4(3): e5004, 2009.
Artículo en Inglés | MEDLINE | ID: mdl-19325915

RESUMEN

Mutations in the gene encoding Cu-Zn superoxide dismutase (SOD1) are one of the causes of familial amyotrophic lateral sclerosis (FALS). Fibrillar inclusions containing SOD1 and SOD1 inclusions that bind the amyloid-specific dye thioflavin S have been found in neurons of transgenic mice expressing mutant SOD1. Therefore, the formation of amyloid fibrils from human SOD1 was investigated. When agitated at acidic pH in the presence of low concentrations of guanidine or acetonitrile, metalated SOD1 formed fibrillar material which bound both thioflavin T and Congo red and had circular dichroism and infrared spectra characteristic of amyloid. While metalated SOD1 did not form amyloid-like aggregates at neutral pH, either removing metals from SOD1 with its intramolecular disulfide bond intact or reducing the intramolecular disulfide bond of metalated SOD1 was sufficient to promote formation of these aggregates. SOD1 formed amyloid-like aggregates both with and without intermolecular disulfide bonds, depending on the incubation conditions, and a mutant SOD1 lacking free sulfhydryl groups (AS-SOD1) formed amyloid-like aggregates at neutral pH under reducing conditions. ALS mutations enhanced the ability of disulfide-reduced SOD1 to form amyloid-like aggregates, and apo-AS-SOD1 formed amyloid-like aggregates at pH 7 only when an ALS mutation was also present. These results indicate that some mutations related to ALS promote formation of amyloid-like aggregates by facilitating the loss of metals and/or by making the intramolecular disulfide bond more susceptible to reduction, thus allowing the conversion of SOD1 to a form that aggregates to form resembling amyloid. Furthermore, the occurrence of amyloid-like aggregates per se does not depend on forming intermolecular disulfide bonds, and multiple forms of such aggregates can be produced from SOD1.


Asunto(s)
Amiloide/metabolismo , Esclerosis Amiotrófica Lateral/genética , Metales/metabolismo , Mutación , Superóxido Dismutasa/genética , Superóxido Dismutasa/metabolismo , Esclerosis Amiotrófica Lateral/enzimología , Disulfuros/metabolismo , Humanos , Concentración de Iones de Hidrógeno , Multimerización de Proteína , Superóxido Dismutasa-1
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