Synthesis and insecticidal activity of N-(5-phenylpyrazin-2-yl)-benzamide derivatives: Elucidation of mode of action on chitin biosynthesis through symptomology and genetic studies.

Among the six-membered heterocycles, the pyrazine ring is poorly explored in crop protection and does not feature in any product listed in the current IRAC MoA classification. In an effort to identify new leads for internal research, we synthesized a series of N-(5-phenylpyrazin-2-yl)-benzamide derivatives and evaluated them for their insecticidal activity. N-(5-phenylpyrazin-2-yl)-benzamide derivatives 3 were prepared using an automated two-step synthesis protocol. These compounds were tested for their initial biological activity against a wide range of sucking and chewing insect pests and found to be active against lepidopterans only. More detailed experiments, including symptomology studies on the diamondback moth, Plutella xylostella (L.) and the Egyptian cotton leafworm, Spodoptera littoralis (Boisduval) showed that analog 3q causes severe abnormalities in the lepidopteran cuticle leading to larval mortality. Compound 3q shows strong potency against both P. xylostella and S. littoralis, whereas analog 3i shows better potency against S. littoralis causing also impaired cuticular structure and death of the larvae. Additionally, P. xylostella genetic studies showed that compound 3q resistance is linked to Chitin Synthase 1. Our studies show that N-(5-phenylpyrazin-2-yl)-benzamide derivatives 3, and in particular analogs 3i and 3q, act as insect growth modulator insecticides. Conformational similarities with lufenuron are discussed.

A novel class of insecticidal alkylsulfones are potent inhibitors of vesicular acetylcholine transport.

Pyridine alkylsulfone derivatives typified by oxazosulfyl (Sumitomo Chemical Company Ltd.) and compound A2 (Syngenta) represent a new class of insecticides, with potent activity against several insect orders. Whilst the MOA of this class has been attributed to interaction with the voltage-gated sodium channel (VGSC), here we present strong evidence that their toxicity to insects is mediated primarily through inhibition of the vesicular acetylcholine transporter (VAChT). Alkylsulfone intoxication in insects is characterised by (i) a reduction in cholinergic synaptic transmission efficiency demonstrated by a depression of cercal afferent activity in giant-interneurone preparations of American cockroach (Periplaneta americana), (ii) selective block of cholinergic-transmission dependent post-synaptic potentials in the Drosophila giant-fibre pathway and (iii) abolition of miniature excitatory post-synaptic currents (mEPSCs) in an identified synapse in Drosophila larvae. Ligand-binding studies using a tritiated example compound ([3H]-A1) revealed a single saturable binding-site, with low nanomolar Kd value, in membrane fractions of green bottle fly (Lucilia sericata). Binding is inhibited by vesamicol and by several examples of a previously identified class of insecticidal compounds known to target VAChT, the spiroindolines. Displacement of this binding by analogues of the radioligand reveals a strong correlation with insecticidal potency. No specific binding was detected in untransformed PC12 cells but a PC12 line stably expressing Drosophila VAChT showed similar affinity for [3H]-A1 as that seen in fly head membrane preparations. Previously identified VAChT point mutations confer resistance to the spiroindoline class of insecticides in Drosophila by Gal-4/UAS directed expression in cholinergic neurones and by CRISPR gene-editing of VAChT, but none of these flies show detectable cross-resistance to this new chemical class. Oxazosulfyl was previously shown to stabilise voltage-gated sodium channels in their slow-inactivated conformation with an IC50 value of 12.3µM but inhibits binding of [3H]-A1 with approximately 5000 times greater potency. We believe this chemistry class represents a novel mode-of-action with high potential for invertebrate selectivity.

The mode of action of isocycloseram: A novel isoxazoline insecticide.

Isocycloseram is a novel isoxazoline insecticide and acaricide with activity against lepidopteran, hemipteran, coleopteran, thysanopteran and dipteran pest species. Isocycloseram selectively targets the invertebrate Rdl GABA receptor at a site that is distinct to fiproles and organochlorines. The widely distributed cyclodiene resistance mutation, A301S, does not affect sensitivity to isocycloseram, either in vitro or in vivo, demonstrating the suitability of isocylsoseram to control pest infestations with this resistance mechanism. Detailed studies demonstrated that the binding sites relevant to the insecticidal activity of avermectins and isocycloseram are distinct. Isocycloseram was shown to compete for binding with metadiamide insecticides related to broflanilide. In addition, a G335M mutation in the third transmembrane domain of the Rdl GABA receptor, impaired the ability of both isocycloseram and metadiamides to block the GABA mediated response. As such the Insecticides Resistance Action Committee (IRAC) has classified isocycloseram in Group 30 "GABA-Gated Chloride Channel Allosteric Modulators".

"Very much evolving": a qualitative study of the views of psychiatrists about peer support workers.

BACKGROUND: Mental health services continue to develop service user involvement, including a growth in employment of peer support workers (PSWs). Despite the importance of the views and attitudes expressed by psychiatrists, this topic has not previously been studied. AIMS: To gain insight into the views and attitudes psychiatrists have about PSWs. METHODS: A qualitative study based on semi-structured interviews with 11 psychiatrists in the East of England. RESULTS: Psychiatrists were broadly positive and supportive of PSWs. Interviewees not only could anticipate a range of possible benefits of employing PSWs, but also had concerns regarding their implementation and management. There was a lack of clarity and consistency between interviewees about what the exact role of a PSW might involve. CONCLUSION: This study provides insights into how PSWs are perceived by psychiatrists. While broadly positive attitudes exist, the research highlights certain challenges, particularly role ambiguity.

Retinal determination genes function along with cell-cell signals to regulate Drosophila eye development: examples of multi-layered regulation by master regulators.

It is thought that retinal determination (RD) gene products define the response made to cell-cell signals in the field of eye development by binding to enhancers of genes that are also regulated by cell-cell signaling pathways. In Drosophila, RD genes, including eyeless, teashirt, eyes absent, dachsous, and sine oculis, are required for normal eye development and can induce ectopic eyes when mis-expressed. Characterization of the enhancers responsible for eye expression of the hedgehog, shaven, and atonal genes, as well as the dynamics of RD gene expression themselves, now suggest a multilayered network whereby transcriptional regulation by either RD genes or cell-cell signaling pathways can sometimes be indirect and mediated by other transcription factor intermediates. In this updated view of the interaction between extracellular information and cell intrinsic programs during development, regulation of individual genes might sometimes be several steps removed from either the RD genes or the cell-cell signaling pathways that nevertheless govern their expression.

A reductionist paradigm for high-throughput behavioural fingerprinting in Drosophila melanogaster.

Understanding how the brain encodes behaviour is the ultimate goal of neuroscience and the ability to objectively and reproducibly describe and quantify behaviour is a necessary milestone on this path. Recent technological progresses in machine learning and computational power have boosted the development and adoption of systems leveraging on high-resolution video recording to track an animal pose and describe behaviour in all four dimensions. However, the high temporal and spatial resolution that these systems offer must come as a compromise with their throughput and accessibility. Here, we describe coccinella, an open-source reductionist framework combining high-throughput analysis of behaviour using real-time tracking on a distributed mesh of microcomputers (ethoscopes) with resource-lean statistical learning (HCTSA/Catch22). Coccinella is a reductionist system, yet outperforms state-of-the-art alternatives when exploring the pharmacobehaviour in Drosophila melanogaster.

Drosophila nicotinic acetylcholine receptor subunits and their native interactions with insecticidal peptide toxins.

Drosophila nicotinic acetylcholine receptors (nAChRs) are ligand-gated ion channels that represent a target for insecticides. Peptide neurotoxins are known to block nAChRs by binding to their target subunits, however, a better understanding of this mechanism is needed for effective insecticide design. To facilitate the analysis of nAChRs we used a CRISPR/Cas9 strategy to generate null alleles for all ten nAChR subunit genes in a common genetic background. We studied interactions of nAChR subunits with peptide neurotoxins by larval injections and styrene maleic acid lipid particles (SMALPs) pull-down assays. For the null alleles, we determined the effects of α-Bungarotoxin (α-Btx) and ω-Hexatoxin-Hv1a (Hv1a) administration, identifying potential receptor subunits implicated in the binding of these toxins. We employed pull-down assays to confirm α-Btx interactions with the Drosophila α5 (Dα5), Dα6, Dα7 subunits. Finally, we report the localisation of fluorescent tagged endogenous Dα6 during Drosophila CNS development. Taken together, this study elucidates native Drosophila nAChR subunit interactions with insecticidal peptide toxins and provides a resource for the in vivo analysis of insect nAChRs.

Regulation of Hh signal transduction as Drosophila eye differentiation progresses.

Differentiation of the Drosophila retina occurs as a morphogenetic furrow sweeps anteriorly across the eye imaginal disc, driven by Hedgehog secretion from photoreceptor precursors differentiating behind the furrow. A BTB protein, Roadkill, is expressed posterior to the furrow and targets the Hedgehog signal transduction component Cubitus interruptus for degradation by Cullin-3 and the proteosome. Clonal analysis and conditional mutant studies establish that roadkill transcription is activated by the EGF receptor and Ras pathway in most differentiating retinal cells, and by both EGF receptor/Ras and by Hedgehog signaling in cells that remain unspecified. These findings outline a circuit by which Hedgehog signal transduction is modified as Hedgehog signaling initiates retinal differentiation. A model is presented for regulation of the Cullin-3 and Cullin-1 pathways that modifies Hedgehog signaling as the morphogenetic furrow moves and the responses of retinal cells change.

Retinal determination genes as targets and possible effectors of extracellular signals.

Retinal determination genes are sufficient to specify eyes in ectopic locations, raising the question of how these master regulatory genes define an eye developmental field. Genetic mosaic studies establish that expression of the retinal determination genes eyeless, teashirt, homothorax, eyes absent, sine oculis, and dachshund are each regulated by combinations of Dpp, Hh, N, Wg, and Ras signals in Drosophila. Dpp and Hh control eyeless, teashirt, sine oculis, and dachshund expression, Dpp and Ras control homothorax, and all the signaling pathways affect eyes absent expression. These results suggest that eye-specific development uses retinal determination gene expression to relay positional information to eye target genes, because the distinct, overlapping patterns of retinal determination gene expression reflect the activities of the extracellular signaling pathways.

Cell cycle arrest by a gradient of Dpp signaling during Drosophila eye development.

BACKGROUND: The secreted morphogen Dpp plays important roles in spatial regulation of gene expression and cell cycle progression in the developing Drosophila eye. Dpp signaling is required for timely cell cycle arrest ahead of the morphogenetic furrow as a prelude to differentiation, and is also important for eye disc growth. The dpp gene is expressed at multiple locations in the eye imaginal disc, including the morphogenetic furrow that sweeps across the eye disc as differentiation initiates. RESULTS: Studies of Brinker and Dad expression, and of Mad phosphorylation, establish that there is a gradient of Dpp signaling in the eye imaginal disc anterior to the morphogenetic furrow, predominantly in the anterior-posterior axis, and also Dpp signaling at the margins of the disc epithelium and in the dorsal peripodial membrane. Almost all signaling activity seems to spread through the plane of the epithelia, although peripodial epithelium cells can also respond to underlying disc cells. There is a graded requirement for Dpp signaling components for G1 arrest in the eye disc, with more stringent requirements further anteriorly where signaling is lower. The signaling level defines the cell cycle response, because elevated signaling through expression of an activated Thickveins receptor molecule arrested cells at more anterior locations. Very anterior regions of the eye disc were not arrested in response to activated receptor, however, and evidence is presented that expression of the Homothorax protein may contribute to this protection. By contrast to activated Thickveins, ectopic expression of processed Dpp leads to very high levels of Mad phosphorylation which appear to have non-physiological consequences. CONCLUSIONS: G1 arrest occurs at a threshold level of Dpp signaling within a morphogen gradient in the anterior eye. G1 arrest is specific for one competent domain in the eye disc, allowing Dpp signaling to promote growth at earlier developmental stages.

Extracellular signals responsible for spatially regulated proliferation in the differentiating Drosophila eye.

Spatially and temporally choreographed cell cycles accompany the differentiation of the Drosophila retina. The extracellular signals that control these patterns have been identified through mosaic analysis of mutations in signal transduction pathways. All cells arrest in G1 prior to the start of neurogenesis. Arrest depends on Dpp and Hh, acting redundantly. Most cells then go through a synchronous round of cell division before fate specification and terminal cell cycle exit. Cell cycle entry is induced by Notch signaling and opposed in subsets of cells by EGF receptor activity. Unusually, Cyclin E levels are not limiting for retinal cell cycles. Rbf/E2F and the Cyclin E antagonist Dacapo are important, however. All retinal cells, including the postmitotic photoreceptor neurons, continue dividing when rbf and dacapo are mutated simultaneously. These studies identify the specific extracellular signals that pattern the retinal cell cycles and show how differentiation can be uncoupled from cell cycle exit.

A comparison of mood and quality of life among people with progressive neurological illnesses and their caregivers.

The current study was designed to investigate differences in mood and a range of QOL domains among 423 patients and 335 caregivers of people with motor neurone disease (MND), Huntington's disease (HD), Parkinson's, and multiple sclerosis (MS). Patients and caregivers completed an anonymous questionnaire that evaluated their mood (anxiety, depression, fatigue, confusion) and QOL (physical, psychological, social, environment). The results demonstrated that caregivers of people with MND and HD experienced most problems with their mood and QOL compared to caregivers of people in the other illness groups. There were few differences in mood or QOL between patients and caregivers. Patients generally showed greater confusion, physical impairment, and psychological maladjustment. The findings suggest that educational and intervention programs need to be developed to help both patients and their caregivers to adjust and cope with these illnesses, particularly caregivers of people with MND and HD.

Techniques and recommendations for the inclusion of users with autism in the design of assistive technologies.

The increasing numbers of technology platforms offer opportunities to develop new visual assistive aids for people with autism. However, their involvement in the design of such aids is critical to their short-term uptake and longer term use. Using a three-round Delphi study involving seven Australian psychologists specializing in treating people with autism, the authors explored the utility of four techniques that might be implemented to involve users with autism in the design process. The authors found that individual users from the target group would be likely to respond differently to the techniques and that no technique was clearly better than any other. Recommendations for using these techniques to involve individuals with autism in the design of assistive technologies are suggested.

The impact of neurological illness on marital relationships.

The current study investigated the impact of neurological illness on marital relationship satisfaction. Participants numbered 423 patients and 335 carers from motor neurone disease (MND), Huntington's disease (HD), Parkinson's, and multiple sclerosis (MS). The results demonstrated that patients and carers with HD had a significantly lower level of relationship satisfaction and sex life satisfaction than the other three illness groups. Further, patients with HD indicated a significantly higher level of relationship satisfaction than their carers. For MS and MND patients, social support predicted marital relationship satisfaction, and for Parkinson's patients, social support and sex life satisfaction predicted marital relationship satisfaction.

Work and recreational changes among people with neurological illness and their caregivers.

BACKGROUND: Progressive neurological illnesses alter the health and well-being of people who experience them, and frequently lead to changes in the activities of both patients and their carers. Purpose. The current study investigated changes in work and recreational activities among people with four of these illnesses. METHOD: In total, the following numbers of people with neurological illnesses and their carers participated in the study: 28 with multiple sclerosis; 27 with motor neurone disease; 31 with Parkinson's; and 24 with Huntingtons disease. In addition, 28 professionals who worked with these populations participated in the study. Individual interviews were conducted with each of the above respondents to determine the impact of the neurological illness. RESULTS: The results demonstrated a high level of agreement from each of the participants. Most of the people with the illnesses and many of the carers had reduced their level of paid work. Generally, all groups of respondents perceived these changes as being negative. Changes in recreational activities were also seen to be primarily negative. CONCLUSIONS: These results are discussed in terms of proposed prevention and intervention programmes to prepare patients and their carers for the changes that result from the neurological illness, strategies to stay at work longer and to help them develop alternative strategies to assist them in filling the gap left in their lives that was previously occupied by paid work.

Satisfaction with services among people with progressive neurological illnesses and their carers in Australia.

The current study investigated the types of support networks and services accessed by people with progressive neurological illness, as well as the assessment of the usefulness of these services. The participants were 25 people with multiple sclerosis, 15 people with motor neurone disease, 23 people with Parkinson's disease, and six people with Huntington's disease. Twenty-eight professionals who worked with people with these illnesses and 41 carers of people with these illnesses also were interviewed. The results demonstrate that all of the groups of respondents indicated a strong need for basic services (e.g. home help), as well as specialized services (e.g. support groups). These two services also were identified as the most useful services by all of the groups of respondents. The similarities and differences between the groups, as well as the patients and carers, are examined. These findings demonstrate the importance of providing basic services for people with progressive neurological illnesses.

The negative impact on nurses of lack of alignment of information systems with public hospital strategic goals.

The objectives of this study were to investigate the degree to which hospital information systems are aligned with hospital strategies and how they impact on nurses. Semi-structured interviews were conducted with nine hospital staff from a range of disciplines in a large public hospital in Australia. The interviews revealed that the focus of hospital information systems on administration has meant that applications to support the patient's clinical journey have been deemed unaffordable. A consequence is that the historic use of the nurses' station as a source of verbal information about patients has continued, with negative impacts on nurses' perceived role and status, and the possible exacerbation of the clash between administrative and clinical cultures. We conclude that hospitals need clear strategies, with alignment of information systems. To do otherwise can undermine culture and morale, while disrupting workflows and patients' clinical journeys.

Analyses of RAS regulation of eye development in Drosophila melanogaster.

Many aspects of Drosophila eye development depend on receptor tyrosine kinases that signal through Ras. Genetic studies and genetic screens using eye morphology and development as assays have identified major components of receptor tyrosine kinase and Ras signaling and outlined specific contributions of these components to cell fate specification and differentiation, cell survival, cell cycle progression and arrest, and cellular movements and morphology. This chapter presents a brief compendium of methods and strains that may be used to obtain overexpression or loss of function for Ras pathway genes in the eye and methods and reagents permitting initial characterization of retinal cell differentiation, death, and cell cycle behavior.

Imaginary Companions in Childhood: Relations to Imagination Skills and Autobiographical Memory in Adults.

The presence of a childhood imaginary companion (IC) has been proposed to reflect heightened imaginative abilities. This study hypothesized that adults who reported having a childhood IC would score higher on a task requiring the imaginative construction of visual scenes. Additionally, it was proposed that individuals who produced more vivid and detailed scenes would also report richer autobiographical memories, due to a shared reliance on imaginative abilities in construction and recollection. Sixty participants (20 with an IC), completed an adapted scene construction procedure and an autobiographical memory questionnaire. Participants reporting a childhood IC scored significantly higher on scene construction and rated themselves as more imaginative. Scene construction scores were also moderately related to the richness of autobiographical memories, although this was almost entirely due to scores on the thought/emotion/action component of scene construction. Autobiographical memory was unrelated to the presence of an IC. Implications for overlapping and dissociable aspects of imagination and memory are discussed.