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1.
Bull Entomol Res ; 110(5): 638-644, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32381143

RESUMO

Telenomus podisi Ashmead (Hymenoptera: Scelionidae) is the most important egg parasitoid of Euschistus heros (Fabricius) (Hemiptera: Pentatomidae), and its successful parasitism is related to their searching ability to find suitable hosts under a complex chemical environment using host-reliable cues. Thus, the objective of this study was to elucidate chemical substances on the external layer of E. heros eggs and report its potential kairomonal activity on T. podisi. We tested female wasps in olfactometer system to synthetic compounds obtained from a chemical identification of E. heros egg masses. The synthetic blend was also evaluated in parasitism tests under laboratory and semi-field conditions. We identified 31 substances from egg surface extracts, including monoterpenes, aldehydes and alkanes. Among those compounds, a synthetic solution including camphene, ß-pinene, limonene and benzaldehyde-induced chemotaxic behaviour on the wasps and increased the parasitism on E. heros eggs, either in laboratory or semi-field test, suggesting its potential use to T. podisi manipulation and parasitism improvement.


Assuntos
Heterópteros/química , Óvulo/química , Feromônios/farmacologia , Vespas/efeitos dos fármacos , Animais , Comportamento Animal/efeitos dos fármacos , Feminino , Heterópteros/parasitologia , Óvulo/parasitologia
2.
Environ Entomol ; 48(1): 211-218, 2019 02 13.
Artigo em Inglês | MEDLINE | ID: mdl-30624627

RESUMO

Halyomorpha halys (Stål) (Heteroptera: Pentatomidae), the brown marmorated stink bug (BMSB), is a polyphagous fruit and vegetable pest from eastern Asia and now invasive in the United States and Europe. Earlier research revealed that the main volatile from hexane egg extracts of a western North American pentatomid, Euschistus conspersus Uhler, to which two native scelionid egg parasitoids, Telenomus podisi Ashmead and Trissolcus erugatus Johnson are highly attracted, was methyl (2E,4Z)-2,4-decadienoate, the major component of the conspecific male-produced aggregation pheromone. Conversely, extracts of BMSB eggs lacked the male-produced sesquiterpenoid H. halys pheromone components but contained C16,18,20 aldehydes (hexadecanal, octadecanal, and eicosanal); both egg-surface extracts of BMSB eggs and the C16,18,20 synthetic aldehyde blend repelled the female parasitoids. The goal of the present research was to manipulate egg-surface volatiles to induce the scelionid egg parasitoids to adopt BMSB eggs as a host. Here it was demonstrated that individual females of both parasitoids could be conditioned to H. halys egg-surface aldehydes in Y-tube olfactometer experiments, and this positive memory lasted 3-4 d. Furthermore, conditioned wasps successfully parasitized fresh H. halys eggs in no choice tests, and their offspring continued to successfully parasitize fresh H. halys eggs for 2-3 more generations. Eventually, both the individual and generational memories faded. Unconditioned female parasitoids were not attracted to H. halys egg extract or the synthetic blend of egg-surface aldehydes, nor did they parasitize BMSB eggs. Theoretical and practical implications of the research are discussed in the contexts of Hopkins' host selection principle, biological control, and instinct evolution.


Assuntos
Heterópteros/parasitologia , Controle Biológico de Vetores/métodos , Vespas/fisiologia , Animais , Feminino , Heterópteros/química , Olfatometria , Óvulo/química , Óvulo/parasitologia , Compostos Orgânicos Voláteis
3.
Neotrop Entomol ; 47(5): 689-697, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-29679311

RESUMO

Parasitoid host selection is mainly mediated by chemical cues, which can be adjusted by experience, changing their innate behavior. Therefore, this study evaluated if immature experience (pre-imaginal conditioning) on eggs and volatiles from different host eggs has influence on parasitism and chemotaxic behavior of Telenomus podisi Ashmead and/or Trissolcus basalis Wollaston (Hymenoptera: Scelionidae). Both wasp species were submitted to a multiple-choice parasitism test among Euschistus heros (Fabricius), Piezodorus guildinii (Westwood), and Nezara viridula L. (Hemiptera: Pentatomidae) (Hemiptera: Pentatomidae) egg masses. Eggs from these three stink bugs were equally offered to female parasitoids. After that, adults which emerged from each host were also exposed to parasitism in a multiple-choice test for up to an additional generation. Moreover, in olfactometer "Y," the behavior of innate and experienced T. podisi females to volatiles from hosts' egg extracts was tested, to study their learning and memory ability. The original host had influence on T. podisi parasitism; however, T. basalis always parasitized more N. viridula eggs independently of its last rearing host. Innate T. podisi females responded positively to E. heros and P. guildinii egg volatiles, but this behavior was not observed in N. viridula. When T. podisi females were experienced on egg volatiles from a new host, they showed significant learning and memory ability for the specific host volatile for, at least, 24 h. Experienced wasps responded positively to N. viridula and through this result we have evidences about the possibility to manipulate wasp's preferences to a specific target host.


Assuntos
Heterópteros/parasitologia , Especificidade de Hospedeiro , Interações Hospedeiro-Parasita , Vespas/fisiologia , Animais , Feminino , Aprendizagem , Olfatometria , Óvulo/química , Óvulo/parasitologia , Compostos Orgânicos Voláteis/química
4.
J Clin Pathol ; 69(10): 926-9, 2016 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-27402956

RESUMO

Despite all the knowledge, the cellular and molecular mechanisms involved in myeloproliferative neoplasm (MPN) pathophysiology remain unclear. Authors have shown galectin-1 (Gal-1) and 3 playing roles in tumour angiogenesis and fibrosis, which were correlated with poor prognosis in patients with MPN. In the present study LGALS1 and LGALS3 were differently expressed between polycythemia vera, essential thrombocythemia (ET) and primary myelofibrosis (PMF) diseases. Increased LGALS3 expression was associated with a negative JAK2 V617F status mutation in leucocytes from PMF but not in patients with ET without this mutation. However, a positive Janus kinase 2 (JAK2) V617F cell line established from patients with ET (SET-2 cells) when treated with JAK inhibitor presented high levels of LGALS3. Additionally, high LGALS1 expression was found in CD34(+) cells but not in leucocytes from patients with PMF, in absence of JAK2 V617F mutation, and also in SET-2 cells treated with JAK inhibitor. Thus, our findings indicate that differential expression of LGALS1 and/or LGALS3 in patients with MPN is linked with JAK2 V617F status mutation in these diseases and state of cell differentiation.


Assuntos
Galectina 1/genética , Galectina 3/genética , Janus Quinase 2/genética , Policitemia Vera/genética , Mielofibrose Primária/genética , Trombocitemia Essencial/genética , Adulto , Substituição de Aminoácidos , Antígenos CD34/genética , Proteínas Sanguíneas , Medula Óssea/patologia , Neoplasias da Medula Óssea/diagnóstico , Neoplasias da Medula Óssea/genética , Neoplasias da Medula Óssea/metabolismo , Linhagem Celular , Galectina 1/metabolismo , Galectina 3/metabolismo , Galectinas , Regulação Neoplásica da Expressão Gênica , Humanos , Janus Quinase 2/metabolismo , Masculino , Pessoa de Meia-Idade , Mutação , Transtornos Mieloproliferativos/diagnóstico , Transtornos Mieloproliferativos/genética , Transtornos Mieloproliferativos/metabolismo , Policitemia Vera/diagnóstico , Policitemia Vera/metabolismo , Mielofibrose Primária/diagnóstico , Mielofibrose Primária/metabolismo , Trombocitemia Essencial/diagnóstico , Trombocitemia Essencial/metabolismo
5.
Bull Entomol Res ; 104(6): 781-7, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25375218

RESUMO

The egg parasitoid Telenomus podisi is a natural control agent of pentatomids, including Euschistus heros and Tibraca limbativentris, and success of parasitism is dependent upon the parasitoid finding the host. We tested the influence of host egg volatiles and the synthetic sex pheromone (zingiberenol) of T. limbativentris on chemotaxic behaviour of T. podisi, as well as, the impact of the original host on parasitoid selection. We used mated female T. podisi (48 h old) that emerged from the eggs of T. limbativentris or E. heros. The bioassays related to chemotaxy were performed in a Y-tube olfactometer and, to parasitism success, in laboratory and semi-field conditions. Telenomus podisi females that emerged from either the stink bug eggs, chose the pheromone more than control, or the pheromone plus eggs of E. heros in the semi-field bioassay, led to greater parasitism. Females that emerged from E. heros eggs chose egg volatiles from their original host rather than those from T. limbativentris, while females emerging from T. limbativentris, chose the egg volatiles of both hosts equally. When T. limbativentris was the original host, T. podisi females parasitized T. limbativentris over E. heros, while those emerging from E. heros exclusively parasitized E. heros eggs. These results demonstrated that T. podisi is more likely to parasitize the host in which it developed and that the original host can exert influence on the choice by those parasitoids. Understanding how the factors that mediate host-parasitoid communication are interrelated can help biological control programmes establish more effective and reliable tools with T. podisi.


Assuntos
Heterópteros/fisiologia , Heterópteros/parasitologia , Interações Hospedeiro-Parasita , Atrativos Sexuais/farmacologia , Compostos Orgânicos Voláteis/farmacologia , Vespas/fisiologia , Animais , Quimiotaxia , Feminino , Heterópteros/crescimento & desenvolvimento , Larva/fisiologia , Ninfa/crescimento & desenvolvimento , Ninfa/parasitologia , Ninfa/fisiologia , Óvulo/fisiologia , Vespas/crescimento & desenvolvimento
6.
Med Oncol ; 30(2): 555, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23568162

RESUMO

Primary myelofibrosis (PM) is a Philadelphia-negative clonal hematopoietic stem cell disorder characterized by intense reactive changes of bone marrow stroma with collagen fibrosis, osteosclerosis and angiogenesis. PM usually affects elderly people, and approximately half of the patients present JAK2V617F mutation. PM clinical course varies from 1 to 30 years, evolving from asymptomatic into progressive bone marrow failure, symptomatic splenomegaly or acute leukemia in 10-20 % of cases. PM risk stratification is based on parameters predicting survival, and several attempts have been made to identify clinical and laboratory features that could predict PM patient survival. This study applied five prognostic scores: Dupriez, Cervantes, Mayo, IPSS and DIPSS-Plus in 62 Brazilians patients from three centers, and compared their relevance and clinical usefulness considering the scores' parameters, fibrosis, JAK2V617F mutation, splenomegaly, hepatomegaly and treatment. According to the Cervantes, Dupriez and Mayo scores, most patients were stratified into low-risk group. However, when IPSS and DIPSS-Plus were applied, most patients were classified into an intermediate range, being low risk in only 11 and 13 % of patients, respectively. Overall survival at 4 years was 84 %. The Cervantes score was the only one that remained significantly associated with survival in a multivariate analysis. In conclusion, the Cervantes score remains important to the prognostication of PM.


Assuntos
Mielofibrose Primária/diagnóstico , Adulto , Idoso , Idoso de 80 Anos ou mais , Brasil , Feminino , Humanos , Janus Quinase 2/genética , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Mielofibrose Primária/classificação , Mielofibrose Primária/enzimologia , Mielofibrose Primária/genética , Prognóstico , Análise de Sobrevida
7.
Clin Exp Immunol ; 168(3): 291-302, 2012 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-22519592

RESUMO

Type 1 diabetes (T1D) is a chronic autoimmune disease characterized by T cell-mediated destruction of pancreatic ß cells, resulting in insulin deficiency and hyperglycaemia. Recent studies have described that apoptosis impairment during central and peripheral tolerance is involved in T1D pathogenesis. In this study, the apoptosis-related gene expression in T1D patients was evaluated before and after treatment with high-dose immunosuppression followed by autologous haematopoietic stem cell transplantation (HDI-AHSCT). We also correlated gene expression results with clinical response to HDI-AHSCT. We observed a decreased expression of bad, bax and fasL pro-apoptotic genes and an increased expression of a1, bcl-x(L) and cIAP-2 anti-apoptotic genes in patients' peripheral blood mononuclear cells (PBMCs) compared to controls. After HDI-AHSCT, we found an up-regulation of fas and fasL and a down-regulation of anti-apoptotic bcl-x(L) genes expression in post-HDI-AHSCT periods compared to pre-transplantation. Additionally, the levels of bad, bax, bok, fasL, bcl-x(L) and cIAP-1 genes expression were found similar to controls 2 years after HDI-AHSCT. Furthermore, over-expression of pro-apoptotic noxa at 540 days post-HDI-AHSCT correlated positively with insulin-free patients and conversely with glutamic acid decarboxylase autoantibodies (GAD65) autoantibody levels. Taken together, the results suggest that apoptosis-related genes deregulation in patients' PBMCs might be involved in breakdown of immune tolerance and consequently contribute to T1D pathogenesis. Furthermore, HDI-AHSCT modulated the expression of some apoptotic genes towards the levels similar to controls. Possibly, the expression of these apoptotic molecules could be applied as biomarkers of clinical remission of T1D patients treated with HDI-AHSCT therapy.


Assuntos
Diabetes Mellitus Tipo 1/imunologia , Diabetes Mellitus Tipo 1/cirurgia , Proteína Ligante Fas/genética , Expressão Gênica , Transplante de Células-Tronco Hematopoéticas , Tolerância Imunológica/genética , Leucócitos Mononucleares/efeitos dos fármacos , Receptor fas/genética , Adolescente , Adulto , Apoptose/genética , Autoanticorpos/metabolismo , Regulação para Baixo , Feminino , Seguimentos , Glutamato Descarboxilase/imunologia , Humanos , Imunossupressores/administração & dosagem , Leucócitos Mononucleares/imunologia , Leucócitos Mononucleares/metabolismo , Leucócitos Mononucleares/patologia , Masculino , Proteínas Proto-Oncogênicas c-bcl-2/genética , Proteínas Proto-Oncogênicas c-bcl-2/imunologia , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Transplante Autólogo , Regulação para Cima , Adulto Jovem , Proteína bcl-X/genética , Proteína bcl-X/imunologia , Proteína bcl-X/metabolismo
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