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1.
J Exp Biol ; 225(15)2022 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-35848820

RESUMO

The often complex cocktails of hydrocarbon compounds found on the cuticles of insects can serve both naturally and sexually selected functions, contributing to an individual's ability to withstand water loss and attract mating partners. However, whether natural and sexual selection act synergistically or antagonistically on a species' cuticular hydrocarbon (CHC) profile remains unclear. Here, we examined the ontogeny of the CHC profile in a species of cricket, Teleogryllus oceanicus, while manipulating humidity during development. We predicted that juvenile crickets should produce only those compounds that contribute to desiccation resistance, while those compounds contributing specifically to male attractiveness should be produced only at sexual maturity. Further, if attractive CHCs come at a cost to desiccation resistance as predicted by some models of sexual selection, then males reared under low humidity should be constrained to invest less in attractive CHCs. Crickets reared under low humidity produced more long-chain methyl-branched alkanes, alkenes and alkadienes than did crickets reared under high humidity. The abundance of n-alkanes was unaffected by humidity treatment. Sexual dimorphism in the CHC profile was not apparent until adult emergence and became exaggerated 10 days after emergence, when crickets were sexually mature. Males produced more of the same compounds that were increased in both sexes under low humidity, but the humidity treatment did not interact with sex in determining CHC abundance. The data suggest that CHC profiles which protect crickets from desiccation might have synergistic effects on male attractiveness, as there was no evidence to suggest males trade-off a CHC profile produced in response to low humidity for one associated with sexual signalling.


Assuntos
Preferência de Acasalamento Animal , Alcanos , Animais , Feminino , Hidrocarbonetos , Masculino , Caracteres Sexuais , Seleção Sexual
2.
Oral Dis ; 27(2): 378-387, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-32609943

RESUMO

OBJECTIVES: To identify factors which influence the intraoral prevalence of human herpes viruses (HHVs) using mucosal swabs, saliva samples and qPCR analysis. METHODOLOGY: In this cross-sectional observational study, matched saliva and oral swabs were collected from a total of 115 subjects: 70 immunocompetent subjects with no mucosal abnormalities, 22 with mucosal abnormalities and 23 therapeutically immunocompromised individuals. Extracted DNA was analysed by multiplex qPCR for detection and quantification of HHVs 1-6. RESULTS: At least one human herpes virus was detected in 77.1% of immunocompetent individuals with no mucosal abnormalities, with EBV the most commonly detected at 61.4%. HHV-6 was detected in 17.1%, HSV-1 in 4.3% and CMV in 1.1%. Detection was higher in saliva than in oral swabs. There was no detection of HSV-2 or VZV. Neither presence of oral mucosal abnormality nor therapeutic immunocompromise was related to increased detection of human herpes virus. CONCLUSION: Commensal detection rates of EBV are high, and caution in clinical correlation of positive detection is warranted. Commensal CMV rates are low, and detection is likely to be clinically relevant. This study presents a comprehensive commensal detection rate of HHVs 1-6 by qPCR in saliva and swabs.


Assuntos
Infecções por Herpesviridae , Vírus , Estudos Transversais , DNA Viral , Infecções por Herpesviridae/diagnóstico , Humanos , Saliva
3.
J Environ Sci Health B ; 55(9): 820-826, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32609071

RESUMO

Fumigation is required as an appropriate biosecurity measure to exterminate insect pests in shipping containers. The aim of this study was to determine if ethyl formate (EF) + nitrogen could be safely applied as an in-transit fumigant for containers transported on land and then by sea. In-transit fumigation trials were conducted in four 20 ft shipping containers during a four-day journey in December 2019 in Western Australia. Ethyl formate (90 g m-3) was released with nitrogen into the containers. Ethyl formate concentrations inside the containers and the surrounding environment on the barge were monitored at timed intervals throughout the overnight voyage. This study added new data on in-transit fumigation with ethyl formate + nitrogen via road and has successfully demonstrated safety of in-transit fumigation with ethyl formate + nitrogen via the marine sector. There was no detectable risk to the public, crew members on the barge or workers throughout the journey. In addition, all tested containers were ready to be opened and unloaded with 5-10 minutes aeration or without aeration upon arrival.


Assuntos
Ésteres do Ácido Fórmico/análise , Fumigação/métodos , Nitrogênio/análise , Austrália , Desenho de Equipamento , Navios , Temperatura
4.
Ann Surg Oncol ; 23(Suppl 5): 746-754, 2016 12.
Artigo em Inglês | MEDLINE | ID: mdl-27577713

RESUMO

BACKGROUND: Esophageal and gastroesophageal junctional (GEJ) adenocarcinoma is one of the most fatal cancers and has the fastest rising incidence rate of all cancers. Identification of biomarkers is needed to tailor treatments to each patient's tumor biology and prognosis. METHODS: Gene expression profiling was performed in a test cohort of 80 chemoradiotherapy (CRTx)-naïve patients with external validation in a separate cohort of 62 CRTx-naïve patients and 169 patients with advanced-stage disease treated with CRTx. RESULTS: As a novel prognostic biomarker after external validation, CD151 showed promise. Patients exhibiting high levels of CD151 (≥median) had a longer median overall survival than patients with low CD151 tumor levels (median not reached vs. 30.9 months; p = 0.01). This effect persisted in a multivariable Cox-regression model with adjustment for tumor stage [adjusted hazard ratio (aHR), 0.33; 95 % confidence interval (CI), 0.14-0.78; p = 0.01] and was further corroborated through immunohistochemical analysis (aHR, 0.22; 95 % CI, 0.08-0.59; p = 0.003). This effect was not found in the separate cohort of CRTx-exposed patients. CONCLUSION: Tumoral expression levels of CD151 may provide independent prognostic information not gained by conventional staging of patients with esophageal and GEJ adenocarcinoma treated by esophagectomy alone.


Assuntos
Adenocarcinoma/genética , Neoplasias Esofágicas/genética , Junção Esofagogástrica , Expressão Gênica , Tetraspanina 24/genética , Adenocarcinoma/metabolismo , Adenocarcinoma/patologia , Adenocarcinoma/terapia , Idoso , Biomarcadores Tumorais/genética , Biomarcadores Tumorais/metabolismo , Quimiorradioterapia Adjuvante , Neoplasias Esofágicas/metabolismo , Neoplasias Esofágicas/patologia , Neoplasias Esofágicas/terapia , Esofagectomia , Feminino , Perfilação da Expressão Gênica , Humanos , Estimativa de Kaplan-Meier , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Prognóstico , Modelos de Riscos Proporcionais , Taxa de Sobrevida , Tetraspanina 24/metabolismo
5.
Ann Surg Oncol ; 22(7): 2431-8, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-25348778

RESUMO

BACKGROUND: Cathepsin E (CTSE), an aspartic proteinase, is differentially expressed in the metaplasia-dysplasia-neoplasia sequence of gastric and colon cancer. We evaluated CTSE in Barrett's esophagus (BE) and cancer because increased CTSE levels are linked to improved survival in several cancers, and other cathepsins are up-regulated in BE and esophageal adenocarcinoma (EAC). METHODS: A total of 273 pretreatment tissues from 199 patients were analyzed [31 normal squamous esophagus (NE), 29 BE intestinal metaplasia, 31 BE with dysplasia (BE/D), 108 EAC]. CTSE relative mRNA expression was measured by real-time polymerase chain reaction, and protein expression was measured by immunohistochemistry. CTSE serum levels were determined by enzyme-linked immunosorbent assay. RESULTS: Median CTSE mRNA expression levels were ≥1,000-fold higher in BE/intestinal metaplasia and BE/D compared to NE. CTSE levels were significantly lower in EAC compared to BE/intestinal metaplasia and BE/D, but significantly higher than NE levels. A similar expression pattern was present in immunohistochemistry, with absent staining in NE, intense staining in intestinal metaplasia and dysplasia, and less intense EAC staining. CTSE serum analysis did not discriminate patient groups. In a uni- and multivariable Cox proportional hazards model, CTSE expression was not significantly associated with survival in patients with EAC, although CTSE expression above the 25th percentile was associated with a 41 % relative risk reduction for death (hazard ratio 0.59, 95 % confidence interval 0.27-1.26, p = 0.17). CONCLUSIONS: CTSE mRNA expression is up-regulated more than any known gene in Barrett intestinal metaplasia and dysplasia tissues. Protein expression is similarly highly intense in intestinal metaplasia and dysplasia tissues.


Assuntos
Adenocarcinoma/metabolismo , Esôfago de Barrett/metabolismo , Catepsina E/sangue , Neoplasias Esofágicas/metabolismo , Esôfago/metabolismo , Metaplasia/metabolismo , Lesões Pré-Cancerosas/metabolismo , Adenocarcinoma/mortalidade , Adenocarcinoma/patologia , Idoso , Esôfago de Barrett/mortalidade , Esôfago de Barrett/patologia , Biomarcadores Tumorais/genética , Biomarcadores Tumorais/metabolismo , Estudos de Casos e Controles , Catepsina E/genética , Ensaio de Imunoadsorção Enzimática , Neoplasias Esofágicas/mortalidade , Neoplasias Esofágicas/patologia , Feminino , Seguimentos , Humanos , Técnicas Imunoenzimáticas , Masculino , Metaplasia/mortalidade , Metaplasia/patologia , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Lesões Pré-Cancerosas/mortalidade , Lesões Pré-Cancerosas/patologia , Prognóstico , RNA Mensageiro/genética , Reação em Cadeia da Polimerase em Tempo Real , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Taxa de Sobrevida
6.
J Gastroenterol Hepatol ; 30(5): 804-20, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-25612140

RESUMO

Barrett's esophagus (BE), a common condition, is the only known precursor to esophageal adenocarcinoma (EAC). There is uncertainty about the best way to manage BE as most people with BE never develop EAC and most patients diagnosed with EAC have no preceding diagnosis of BE. Moreover, there have been recent advances in knowledge and practice about the management of BE and early EAC. To aid clinical decision making in this rapidly moving field, Cancer Council Australia convened an expert working party to identify pertinent clinical questions. The questions covered a wide range of topics including endoscopic and histological definitions of BE and early EAC; prevalence, incidence, natural history, and risk factors for BE; and methods for managing BE and early EAC. The latter considered modification of lifestyle factors; screening and surveillance strategies; and medical, endoscopic, and surgical interventions. To answer each question, the working party systematically reviewed the literature and developed a set of recommendations through consensus. Evidence underpinning each recommendation was rated according to quality and applicability.


Assuntos
Adenocarcinoma/diagnóstico , Esôfago de Barrett/diagnóstico , Neoplasias Esofágicas/diagnóstico , Guias de Prática Clínica como Assunto , Adenocarcinoma/patologia , Adenocarcinoma/terapia , Austrália , Esôfago de Barrett/patologia , Esôfago de Barrett/terapia , Biomarcadores Tumorais/análise , Neoplasias Esofágicas/patologia , Neoplasias Esofágicas/terapia , Esofagoscopia , Previsões , Humanos , Fatores de Risco
7.
BMC Cancer ; 14: 54, 2014 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-24485021

RESUMO

BACKGROUND: The development of colorectal cancer (CRC) is accompanied by extensive epigenetic changes, including frequent regional hypermethylation particularly of gene promoter regions. Specific genes, including SEPT9, VIM1 and TMEFF2 become methylated in a high fraction of cancers and diagnostic assays for detection of cancer-derived methylated DNA sequences in blood and/or fecal samples are being developed. There is considerable potential for the development of new DNA methylation biomarkers or panels to improve the sensitivity and specificity of current cancer detection tests. METHODS: Combined epigenomic methods - activation of gene expression in CRC cell lines following DNA demethylating treatment, and two novel methods of genome-wide methylation assessment - were used to identify candidate genes methylated in a high fraction of CRCs. Multiplexed amplicon sequencing of PCR products from bisulfite-treated DNA of matched CRC and non-neoplastic tissue as well as healthy donor peripheral blood was performed using Roche 454 sequencing. Levels of DNA methylation in colorectal tissues and blood were determined by quantitative methylation specific PCR (qMSP). RESULTS: Combined analyses identified 42 candidate genes for evaluation as DNA methylation biomarkers. DNA methylation profiles of 24 of these genes were characterised by multiplexed bisulfite-sequencing in ten matched tumor/normal tissue samples; differential methylation in CRC was confirmed for 23 of these genes. qMSP assays were developed for 32 genes, including 15 of the sequenced genes, and used to quantify methylation in tumor, adenoma and non-neoplastic colorectal tissue and from healthy donor peripheral blood. 24 of the 32 genes were methylated in >50% of neoplastic samples, including 11 genes that were methylated in 80% or more CRCs and a similar fraction of adenomas. CONCLUSIONS: This study has characterised a panel of 23 genes that show elevated DNA methylation in >50% of CRC tissue relative to non-neoplastic tissue. Six of these genes (SOX21, SLC6A15, NPY, GRASP, ST8SIA1 and ZSCAN18) show very low methylation in non-neoplastic colorectal tissue and are candidate biomarkers for stool-based assays, while 11 genes (BCAT1, COL4A2, DLX5, FGF5, FOXF1, FOXI2, GRASP, IKZF1, IRF4, SDC2 and SOX21) have very low methylation in peripheral blood DNA and are suitable for further evaluation as blood-based diagnostic markers.


Assuntos
Biomarcadores Tumorais/genética , Neoplasias Colorretais/genética , Metilação de DNA/genética , Regulação Neoplásica da Expressão Gênica , Estudos de Associação Genética/métodos , Biomarcadores Tumorais/metabolismo , Neoplasias Colorretais/diagnóstico , Neoplasias Colorretais/metabolismo , Células HCT116 , Células HT29 , Humanos
8.
Sci Rep ; 13(1): 2744, 2023 02 16.
Artigo em Inglês | MEDLINE | ID: mdl-36797315

RESUMO

Invasive species eradication campaigns often fail due to stochastic arrival events, unpredictable detectability and incorrect resource allocation. Severe uncertainty in model parameter estimates may skew the eradication policy results. Using info-gap decision theory, this research aims to provide managers with a method to quantify their confidence in realizing successful eradication of particular invasive species within their specified eradication budgets (i.e. allowed eradication cost) in face of information-gaps. The potential introduction of the Asian house gecko Hemidactylus frenatus to Barrow Island, Australia is used as a case study to illustrate the model. Results of this research demonstrate that, more robustness to uncertainty in the model parameters can be earnt by (1) increasing the allowed eradication cost (2) investment in pre-border quarantine and border inspection (i.e. prevention) or (3) investment in post-border detection surveillance. The combination of a post-border spatial dispersal model and info-gap decision theory demonstrates a novel and spatially efficient method for managers to evaluate the robustness of eradication policies for incursion of invasive species with unexpected behaviour. These methods can be used to provide insight into the success of management goals, in particular the eradication of invasive species on islands or in broader mainland areas. These insights will assist in avoiding eradication failure and wasteful budget allocation and labour investment.


Assuntos
Espécies Introduzidas , Lagartos , Animais , Análise Custo-Benefício , Incerteza , Austrália , Políticas
9.
Ecol Evol ; 13(7): e10244, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37404700

RESUMO

Global declines in insect abundance are of significant concern. While there is evidence that climate change is contributing to insect declines, we know little of the direct mechanisms responsible for these declines. Male fertility is compromised by increasing temperatures, and the thermal limit to fertility has been implicated as an important factor in the response of insects to climate change. However, climate change is affecting both temperature and hydric conditions, and the effects of water availability on male fertility have rarely been considered. Here we exposed male crickets Teleogryllus oceanicus to either low or high-humidity environments while holding temperature constant. We measured water loss and the expression of both pre- and postmating reproductive traits. Males exposed to a low-humidity environment lost more water than males exposed to a high-humidity environment. A male's cuticular hydrocarbon profile (CHC) did not affect the amount of water lost, and males did not adjust the composition of their CHC profiles in response to hydric conditions. Males exposed to a low-humidity environment were less likely to produce courtship song or produced songs of low quality. Their spermatophores failed to evacuate and their ejaculates contained sperm of reduced viability. The detrimental effects of low-humidity on male reproductive traits will compromise male fertility and population persistence. We argue that limits to insect fertility based on temperature alone are likely to underestimate the true effects of climate change on insect persistence and that the explicit incorporation of water regulation into our modeling will yield more accurate predictions of the effects of climate change on insect declines.

10.
Proc Biol Sci ; 278(1721): 3123-8, 2011 Oct 22.
Artigo em Inglês | MEDLINE | ID: mdl-21367785

RESUMO

Cuticular hydrocarbons provide arthropods with the chemical equivalent of the visually extravagant plumage of birds. Their long chain length, together with the number and variety of positions in which methyl branches and double bonds occur, provide cuticular hydrocarbons with an extraordinary level of information content. Here, we demonstrate phenotypic plasticity in an individual's cuticular hydrocarbon profile. Using solid-phase microextraction, a chemical technique that enables multiple sampling of the same individual, we monitor short-term changes in cuticular hydrocarbon profiles of individual crickets, Teleogryllus oceanicus, in response to a social challenge. We experimentally manipulate the dominance status of males and find that dominant males, on losing fights with other dominant males, change their hydrocarbon profile to more closely resemble that of a subordinate. This result demonstrates that cuticular hydrocarbons can be far more responsive to changes in social dominance than previously realized.


Assuntos
Gryllidae/química , Gryllidae/fisiologia , Hidrocarbonetos/análise , Feromônios/análise , Predomínio Social , Animais , Cromatografia Gasosa-Espectrometria de Massas , Masculino , Fenótipo , Comportamento Sexual Animal , Microextração em Fase Sólida , Austrália Ocidental
11.
Sci Rep ; 11(1): 22828, 2021 11 24.
Artigo em Inglês | MEDLINE | ID: mdl-34819566

RESUMO

Invasive species can lead to community-level damage to the invaded ecosystem and extinction of native species. Most surveillance systems for the detection of invasive species are developed based on expert assessment, inherently coming with a level of uncertainty. In this research, info-gap decision theory (IGDT) is applied to model and manage such uncertainty. Surveillance of the Asian House Gecko, Hemidactylus frenatus Duméril and Bibron, 1836 on Barrow Island, is used as a case study. Our research provides a novel method for applying IGDT to determine the population threshold ([Formula: see text]) so that the decision can be robust to the deep uncertainty present in model parameters. We further robust-optimize surveillance costs rather than minimize surveillance costs. We demonstrate that increasing the population threshold for detection increases both robustness to the errors in the model parameter estimates, and opportuneness to lower surveillance costs than the accepted maximum budget. This paper provides guidance for decision makers to balance robustness and required surveillance expenditure. IGDT offers a novel method to model and manage the uncertainty prevalent in biodiversity conservation practices and modelling. The method outlined here can be used to design robust surveillance systems for invasive species in a wider context, and to better tackle uncertainty in protection of biodiversity and native species in a cost-effective manner.


Assuntos
Monitoramento Ambiental/economia , Espécies Introduzidas , Lagartos/fisiologia , Animais , Biodiversidade , Orçamentos , Conservação dos Recursos Naturais , Análise Custo-Benefício , Modelos Estatísticos , Densidade Demográfica , Especificidade da Espécie , Incerteza
12.
J Evol Biol ; 23(4): 707-14, 2010 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-20210834

RESUMO

Sexual dimorphism is thought to result from directional sexual selection acting on male signal traits, with female signal traits given little, if any, attention. Here, we examine male mating preferences in the Australian field cricket, Teleogryllus oceanicus. Using a multivariate selection analysis approach, we found that male preferences have the potential to exert selection on female cuticular hydrocarbons, chemical compounds widely used as sexual signals in insects. In addition to finding both stabilizing and disruptive preference gradients, we also found weak negative directional preference for female cuticular hydrocarbons. We contrast our results with a recent study examining sexual selection via female choice on male T. oceanicus cuticular hydrocarbons and suggest that differences in the form and intensity of sexual selection between the genders may provide part of the net selection differential necessary for the evolution of sexual dimorphism in this species.


Assuntos
Gryllidae/fisiologia , Hidrocarbonetos/química , Hidrocarbonetos/farmacologia , Tegumento Comum/fisiologia , Comportamento Sexual Animal/efeitos dos fármacos , Animais , Feminino , Masculino , Análise de Componente Principal , Comportamento Sexual Animal/fisiologia
13.
Proteomics ; 9(7): 1883-92, 2009 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-19294694

RESUMO

Bladder cancer (BLCa) is a severe urological cancer of both men and women that commonly recurs and once invasive, is difficult to treat. MINA-05 (CK Life Sciences Int'l, Hong Kong) is a derivative of complex botanical extracts, shown to reduce cellular proliferation of bladder and prostate carcinomas. We tested the effects of MINA-05 against human BLCa cell sublines, B8, B8-RSP-GCK, B8-RSP-LN and C3, from a transitional cell carcinoma, grade IV, to determine the molecular targets of treatment by observing the cellular protein profile. Cells were acclimatised for 48 h then treated for 72 h with concentrations of MINA-05 reflecting 1/2 IC(50), IC(50) and 2 x IC(50) (n = 3) or with vehicle, (0.5% DMSO). Dose-dependant changes in protein abundance were detected and characterised using 2-dimensional electrophoresis and MS. We identified 10 proteins that underwent changes in abundance, pI and/or molecular mass in response to treatment. MINA-05 was shown to influence proteins across numerous functional classes including cytoskeletal proteins, energy metabolism proteins, protein degradation proteins and tumour suppressors, suggesting a global impact on these cell lines. This study implies that the ability of MINA-05 to retard cellular proliferation is attributed to its ability to alter cell cycling, metabolism, protein degradation and the cancer cell environment.


Assuntos
Medicamentos de Ervas Chinesas/farmacologia , Perfilação da Expressão Gênica , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Neoplasias da Bexiga Urinária/metabolismo , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Eletroforese em Gel Bidimensional , Humanos , Proteínas de Neoplasias/metabolismo , Fosfopiruvato Hidratase/metabolismo , Schisandra , Glycine max , Yucca
14.
BMC Evol Biol ; 9: 162, 2009 Jul 13.
Artigo em Inglês | MEDLINE | ID: mdl-19594896

RESUMO

BACKGROUND: Females in a wide range of taxa have been shown to base their choice of mates on pheromone signals. However, little research has focussed specifically on the form and intensity of selection that mate choice imposes on the pheromone signal. Using multivariate selection analysis, we characterise directly the form and intensity of sexual selection acting on cuticular hydrocarbons, chemical compounds widely used in the selection of mates in insects. Using the Australian field cricket Teleogryllus oceanicus as a model organism, we use three measures of male attractiveness to estimate fitness; mating success, the duration of courtship required to elicit copulation, and subsequent spermatophore attachment duration. RESULTS: We found that all three measures of male attractiveness generated sexual selection on male cuticular hydrocarbons, however there were differences in the form and intensity of selection among these three measures. Mating success was the only measure of attractiveness that imposed both univariate linear and quadratic selection on cuticular hydrocarbons. Although we found that all three attractiveness measures generated nonlinear selection, again only mating success was found to exert statistically significant stabilizing selection. CONCLUSION: This study shows that sexual selection plays an important role in the evolution of male cuticular hydrocarbon signals.


Assuntos
Gryllidae/fisiologia , Hidrocarbonetos/química , Preferência de Acasalamento Animal , Seleção Genética , Atrativos Sexuais/química , Animais , Evolução Biológica , Copulação , Feminino , Gryllidae/química , Gryllidae/genética , Proteínas de Insetos/genética , Masculino , Análise Multivariada , Análise de Componente Principal , Característica Quantitativa Herdável
15.
Proc Biol Sci ; 276(1655): 383-8, 2009 Jan 22.
Artigo em Inglês | MEDLINE | ID: mdl-18854298

RESUMO

Female sexual promiscuity can have significant effects on male mating decisions because it increases the intensity of competition between ejaculates for fertilization. Because sperm production is costly, males that can detect multiple matings by females and allocate sperm strategically will have an obvious fitness advantage. The presence of rival males is widely recognized as a cue used by males to assess sperm competition. However, for species in which males neither congregate around nor guard females, other more cryptic cues might be involved. Here, we demonstrate unprecedented levels of sperm competition assessment by males, which is mediated via the use of chemical cues. Using the cricket Teleogryllus oceanicus, we manipulated male perception of sperm competition by experimentally coating live unmated females with cuticular compounds extracted from males. We found that males adjusted their ejaculate allocation in response to these compounds: the viability of sperm contained within a male's ejaculate decreased as the number of male extracts applied to his virgin female partner was increased. We further show that males do not respond to the relative concentration of male compounds present on females, but rather to the number of distinct signature odours of individual males. Our results conform to sperm competition theory, and show for the first time, to our knowledge, that males can detect different intensities of sperm competition by using distinct chemical cues of individual males present on females.


Assuntos
Gryllidae/fisiologia , Hidrocarbonetos/farmacologia , Comportamento Sexual Animal/efeitos dos fármacos , Espermatozoides/fisiologia , Animais , Sinais (Psicologia) , Ejaculação/efeitos dos fármacos , Ejaculação/fisiologia , Feminino , Gryllidae/efeitos dos fármacos , Gryllidae/metabolismo , Hidrocarbonetos/metabolismo , Masculino , Estimulação Química
16.
Sci Rep ; 9(1): 19339, 2019 12 18.
Artigo em Inglês | MEDLINE | ID: mdl-31852943

RESUMO

Large sea-going passenger vessels can pose a high biosecurity risk. The risk posed by marine species is well documented, but rarely the risk posed by terrestrial arthropods. We conducted the longest running, most extensive monitoring program of terrestrial arthropods undertaken on board a passenger vessel. Surveillance was conducted over a 19-month period on a large passenger (cruise) vessel that originated in the Baltic Sea (Estonia). The vessel was used as an accommodation facility to house workers at Barrow Island (Australia) for 15 months, during which 73,061 terrestrial arthropods (222 species - four non-indigenous (NIS) to Australia) were collected and identified on board. Detection of Tribolium destructor Uytt., a high-risk NIS to Australia, triggered an eradication effort on the vessel. This effort totalled more than 13,700 human hours and included strict biosecurity protocols to ensure that this and other non-indigenous species (NIS) were not spread from the vessel to Barrow Island or mainland Australia. Our data demonstrate that despite the difficulties of biosecurity on large vessels, stringent protocols can stop NIS spreading from vessels, even where vessel-wide eradication is not possible. We highlight the difficulties associated with detecting and eradicating NIS on large vessels and provide the first detailed list of species that inhabit a vessel of this kind.


Assuntos
Artrópodes/fisiologia , Navios , Animais , Austrália , Estônia , Geografia , Ilhas , Oceanos e Mares , Análise de Regressão , Risco , Especificidade da Espécie
17.
Sci Rep ; 9(1): 17052, 2019 11 19.
Artigo em Inglês | MEDLINE | ID: mdl-31745186

RESUMO

Next generation sequencing has revolutionised genomic studies of cancer, having facilitated the development of precision oncology treatments based on a tumour's molecular profile. We aimed to develop a targeted gene sequencing panel for application to disparate cancer types with particular focus on tumours of the head and neck, plus test for utility in liquid biopsy. The final panel designed through Roche/Nimblegen combined 451 cancer-associated genes (2.01 Mb target region). 136 patient DNA samples were collected for performance and application testing. Panel sensitivity and precision were measured using well-characterised DNA controls (n = 47), and specificity by Sanger sequencing of the Aryl Hydrocarbon Receptor Interacting Protein (AIP) gene in 89 patients. Assessment of liquid biopsy application employed a pool of synthetic circulating tumour DNA (ctDNA). Library preparation and sequencing were conducted on Illumina-based platforms prior to analysis with our accredited (ISO15189) bioinformatics pipeline. We achieved a mean coverage of 395x, with sensitivity and specificity of >99% and precision of >97%. Liquid biopsy revealed detection to 1.25% variant allele frequency. Application to head and neck tumours/cancers resulted in detection of mutations aligned to published databases. In conclusion, we have developed an analytically-validated panel for application to cancers of disparate types with utility in liquid biopsy.


Assuntos
Carcinoma Ductal Pancreático/genética , Predisposição Genética para Doença/genética , Neoplasias de Cabeça e Pescoço/genética , Neoplasias Pancreáticas/genética , Neoplasias Hipofisárias/genética , Carcinoma de Células Escamosas de Cabeça e Pescoço/genética , Biomarcadores Tumorais/genética , Linhagem Celular Tumoral , DNA Tumoral Circulante/genética , Biologia Computacional/métodos , Genômica/métodos , Sequenciamento de Nucleotídeos em Larga Escala/métodos , Humanos , Biópsia Líquida , Medicina de Precisão/métodos , Sensibilidade e Especificidade
18.
J Insect Physiol ; 54(6): 1081-9, 2008 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-18519139

RESUMO

Sexual dimorphism is presumed to reflect adaptive divergence in response to selection favouring different optimal character states in the two sexes. Here, we analyse patterns of sexual dimorphism in the cuticular hydrocarbons of the Australian field cricket Teleogryllus oceanicus using gas chromatography. Ten of the 25 peaks found in our chromatographs, differed in their relative abundance between the sexes. The presence of sexual dimorphism in T. oceanicus is discussed in reference to a review of sexual dimorphism in cuticular hydrocarbons of other insects. We found that this trait has been examined in 103 species across seven different orders. Seventy-six of these species (73%) displayed sex specificity of cuticular hydrocarbons, the presence/absence of which does not appear to be directly linked to phylogeny. The occurrence of sexual dimorphism in cuticular hydrocarbons of some but not other species, and the extent of variation within genera, suggest that this divergence has been driven primarily by sexual selection.


Assuntos
Evolução Biológica , Gryllidae/metabolismo , Hidrocarbonetos/metabolismo , Caracteres Sexuais , Animais , Cromatografia Gasosa , Feminino , Masculino
19.
Am Nat ; 170(2): 190-5, 2007 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-17874370

RESUMO

Sperm competition theory predicts that males should allocate sperm according to the number of competing ejaculates. Prudent allocation of sperm in response to different levels of sperm competition has been found across a number of taxa; however, some studies suggest that males may not always allocate sperm as expected. Here we examine sperm allocation in the Australian field cricket Teleogryllus oceanicus, using female mating status (virgin, singly mated, or multiply mated) to manipulate male perception of sperm competition risk and intensity. Consistent with theory, we found that male crickets adjust their ejaculates in response to female mating status. However, rather than altering the absolute numbers of sperm transferred to a female, males altered the quality of their sperm. Males ejaculated sperm of low viability (proportion of live vs. dead sperm) when mating with virgins, increased sperm viability when mating with singly mated females, but reduced sperm viability when mating with multiply mated females. Our results show that variation in ejaculate quality can be an important aspect of strategic ejaculation by males and suggest caution in the interpretation of studies in which males do not appear to allocate sperm according to theory.


Assuntos
Fertilização/fisiologia , Gryllidae/fisiologia , Comportamento Sexual Animal/fisiologia , Espermatozoides/fisiologia , Animais , Sobrevivência Celular , Feminino , Masculino , Contagem de Espermatozoides
20.
Mol Cancer Res ; 15(11): 1558-1569, 2017 11.
Artigo em Inglês | MEDLINE | ID: mdl-28751461

RESUMO

Esophageal adenocarcinoma (EAC) has one of the fastest increases in incidence of any cancer, along with poor five-year survival rates. Barrett's esophagus (BE) is the main risk factor for EAC; however, the mechanisms driving EAC development remain poorly understood. Here, transcriptomic profiling was performed using RNA-sequencing (RNA-seq) on premalignant and malignant Barrett's tissues to better understand this disease. Machine-learning and network analysis methods were applied to discover novel driver genes for EAC development. Identified gene expression signatures for the distinction of EAC from BE were validated in separate datasets. An extensive analysis of the noncoding RNA (ncRNA) landscape was performed to determine the involvement of novel transcriptomic elements in Barrett's disease and EAC. Finally, transcriptomic mutational investigation of genes that are recurrently mutated in EAC was performed. Through these approaches, novel driver genes were discovered for EAC, which involved key cell cycle and DNA repair genes, such as BRCA1 and PRKDC. A novel 4-gene signature (CTSL, COL17A1, KLF4, and E2F3) was identified, externally validated, and shown to provide excellent distinction of EAC from BE. Furthermore, expression changes were observed in 685 long noncoding RNAs (lncRNA) and a systematic dysregulation of repeat elements across different stages of Barrett's disease, with wide-ranging downregulation of Alu elements in EAC. Mutational investigation revealed distinct pathways activated between EAC tissues with or without TP53 mutations compared with Barrett's disease. In summary, transcriptome sequencing revealed altered expression of numerous novel elements, processes, and networks in EAC and premalignant BE.Implications: This study identified opportunities to improve early detection and treatment of patients with BE and esophageal adenocarcinoma. Mol Cancer Res; 15(11); 1558-69. ©2017 AACR.


Assuntos
Adenocarcinoma/genética , Esôfago de Barrett/genética , Neoplasias Esofágicas/genética , Sequenciamento do Exoma/métodos , Perfilação da Expressão Gênica/métodos , Mutação , Biomarcadores Tumorais/genética , Proteínas de Ciclo Celular/genética , Feminino , Redes Reguladoras de Genes , Humanos , Fator 4 Semelhante a Kruppel , Aprendizado de Máquina , Masculino , RNA não Traduzido/genética , Análise de Sequência de RNA/métodos
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