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1.
J Eur Acad Dermatol Venereol ; 29(3): 498-506, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25059687

RESUMO

BACKGROUND: To date, there is no global consensus on the definition of the severity of psoriasis. The REFlective evaLuation of psoriasis Efficacy of Treatment and Severity (REFLETS) questionnaire has recently been developed to provide a better understanding of plaque-type psoriasis severity and treatment efficacy from both patient and clinician perspectives. OBJECTIVE: This study aimed to develop and psychometrically validate the new REFLETS questionnaire to evaluate patient and clinician perceptions of plaque-type psoriasis severity and treatment efficacy. METHODS: Two similar versions of the REFLETS questionnaire were developed following a rigorous methodology for clinicians and patients, referring to 'the psoriasis of your patient' or to 'your psoriasis', respectively. An observational, longitudinal, multicentre study was conducted in France with 34 dermatologists and 430 mild to severe plaque-type psoriasis patients to finalize the questionnaire and evaluate its psychometric properties. RESULTS: Two dimensions were defined--severity and treatment efficacy--with three subdimensions within severity (impact of psoriasis, symptoms and disease course), and two individual items on joint pain. The questionnaire was well accepted by clinicians and patients. Excellent internal consistency (Cronbach's alpha = 0.66-0.98) and test-retest reliability (intraclass correlation coefficients = 0.83-0.94) were demonstrated. REFLETS scores were moderately to highly correlated to Psoriasis Area and Severity Index (r = 0.35-0.70), Skindex-29 (r = 0.46-0.82) and DLQI scores (r = 0.36-0.82). Patients with decreased psoriasis severity and those with increased treatment efficacy, according to patient global evaluations, had lower severity and higher treatment efficacy REFLETS scores, respectively. CONCLUSION: REFlective evaLuation of psoriasis Efficacy of Treatment and Severity is a promising tool for assessing plaque-type psoriasis severity and treatment efficacy from patient and clinician perspectives. It may help to improve patient and clinician communication in treatment decision making.


Assuntos
Psoríase/tratamento farmacológico , Psicometria , Adulto , Animais , Gatos , Feminino , Humanos , Masculino , Psoríase/fisiopatologia , Índice de Gravidade de Doença , Inquéritos e Questionários , Resultado do Tratamento
2.
J Hypertens ; 11(5): 559-64, 1993 May.
Artigo em Inglês | MEDLINE | ID: mdl-8390528

RESUMO

AIM: To compare the effects of an angiotensin converting enzyme (ACE) inhibitor and a thiazide diuretic on platelet function and haemorrheological variables, since these factors may contribute to the atherosclerotic and thrombotic complications associated with hypertension. METHODS: Following a 2-week placebo period, 80 male and female patients with mild to moderate hypertension, aged 50 +/- 10 (mean +/- SD) years, were randomly allocated in a double-blind study to 4 weeks of treatment with the ACE inhibitor lisinopril at 20 mg once a day or the diuretic hydrochlorothiazide at 25 mg once a day. Venous blood was sampled before and at the end of the 4-week treatment period to assess platelet function and haemorrheological variables. RESULTS: Both treatments lowered systolic and diastolic blood pressure equally and had no significant effect on platelet counts and platelet aggregation in response to ADP and to arachidonic acid. Haematocrit plasma viscosity and blood filterability were not altered by either drug. Hydrochlorothiazide tended to increase and lisinopril tended to decrease whole blood viscosity at all shear rates but these changes did not reach statistical significance. Lisinopril increased the erythrocyte aggregation time (from 1.98 +/- 0.50 to 2.08 +/- 0.52 s) and decreased the disaggregation shear rate (from 159 +/- 46 to 153 +/- 40 s-1) and the disaggregation shear stress (from 705 +/- 257 to 659 +/- 204 mPa). Hydrochlorothiazide induced the opposite effects (2.00 +/- 0.47 to 1.92 +/- 0.39 s, 181 +/- 531 to 196 +/- 82 s-1 and 813 +/- 268 to 868 +/- 392 mPa, respectively) with a statistically significant (P < 0.05) intergroup difference. CONCLUSIONS: These findings suggest that chronic treatment with the ACE inhibitor lisinopril, but not the diuretic hydrochlorothiazide, may produce favourable effects on blood rheology, but the clinical relevance requires further investigation.


Assuntos
Inibidores da Enzima Conversora de Angiotensina/farmacologia , Plaquetas/efeitos dos fármacos , Viscosidade Sanguínea/efeitos dos fármacos , Dipeptídeos/farmacologia , Hidroclorotiazida/farmacologia , Hipertensão/sangue , Adulto , Idoso , Plaquetas/fisiologia , Pressão Sanguínea/efeitos dos fármacos , Agregação Celular/efeitos dos fármacos , Método Duplo-Cego , Feminino , Humanos , Hipertensão/tratamento farmacológico , Lisinopril , Masculino , Pessoa de Meia-Idade
3.
Proc Biol Sci ; 269(1503): 1879-86, 2002 Sep 22.
Artigo em Inglês | MEDLINE | ID: mdl-12350249

RESUMO

Proteins isolated from the host cocoon of Acrolepiopsis assectella (Lepidoptera: Yponomeutoidea) act as kairomones for host acceptance by the endoparasitoid wasp Diadromus pulchellus Wesmael (Hymenoptera: Ichneumonidae). In this study, morphological, ultrastructural and electrophysiological studies were carried out in order to identify the contact chemoreceptive sensilla on the parasitoid antennae that perceive the protein kairomones. Three types of sensillum on the antennae of the females were found to have a chemosensory function. The receptor cell(s) of one sensillar type were shown to give a positive electrophysiological response to protein kairomones. This sensillar type is apically multiporous and female specific. Consequently, this sensillum could be the one implicated in the perception of the protein kairomone that triggers the host-acceptance behaviour of D. pulchellus females.


Assuntos
Lepidópteros/química , Lepidópteros/parasitologia , Feromônios/farmacologia , Vespas/efeitos dos fármacos , Vespas/fisiologia , Animais , Comportamento Animal/efeitos dos fármacos , Eletrofisiologia , Feminino , Interações Hospedeiro-Parasita/efeitos dos fármacos , Órgãos dos Sentidos/anatomia & histologia , Órgãos dos Sentidos/efeitos dos fármacos , Órgãos dos Sentidos/fisiologia , Órgãos dos Sentidos/ultraestrutura , Vespas/anatomia & histologia , Vespas/ultraestrutura
4.
J Hum Hypertens ; 9 Suppl 4: S41-6, 1995 Aug.
Artigo em Francês | MEDLINE | ID: mdl-7674273

RESUMO

As in hypertension, the addition of a second active drug is believed to enhance treatment efficacy; however, the extent to which a combination of two low-dose drugs outperforms conventional monotherapy remains uncertain. Established treatments of angina comprises nitrates compounds, beta-blockers and calcium antagonists, which are often given in combination. Beta-blockers are major players in this field as they inhibit the tachycardia induced by nitrates and calcium antagonists; there is therefore a pathophysiological justification for their use in combination therapy, supported by repeated confirmation of positive clinical effect. The most widely chosen calcium antagonists are dihydropyridines; verapamil may impair conduction. However, it is not clear whether combination enhances the effects of the individual antianginal substances. Diuretics are for most clinicians the keystone treatment of heart failure; diuretics are often combined with other drugs, e.g. amiloride and spironolactone. The latter also have a beneficial effect on myocardial structure (myocardium/collagen ratio). ACE-inhibitors are of proven clinical efficacy, and, in addition, have a beneficial effect on survival. They combine well with diuretics: because the diuretic stimulates renin release, the ACE-inhibitor can be given at a lower dose (enhancement of effect). There are, however, certain drawbacks (hypotension, hyperkalemia with antialdosterones). The results of combining ACE-inhibitors with calcium antagonists and beta-blockers await investigation. The ISIS studies demonstrated the advantages of combining beta-blockers, thrombolysis and aspirin in acute infarction. ACE-inhibitors have recently been added to the regimen with a positive effect (extended survival), especially in the presence of a decreased ejection fraction (SAVE, AIRE, GISSI 3 and ISIS 4 studies).(ABSTRACT TRUNCATED AT 250 WORDS)


Assuntos
Doenças Cardiovasculares/tratamento farmacológico , Angina Pectoris/tratamento farmacológico , Quimioterapia Combinada , Insuficiência Cardíaca/tratamento farmacológico , Humanos , Hipertensão/tratamento farmacológico , Infarto do Miocárdio/tratamento farmacológico
5.
Fundam Clin Pharmacol ; 11(3): 221-30, 1997.
Artigo em Inglês | MEDLINE | ID: mdl-9243253

RESUMO

The increased sympathetic drive in chronic heart failure (CHF) might provoke vascular adrenoceptor desensitization, which, together with endothelial dysfunction, could contribute to the altered vasomotor tone seen in CHF. We investigated 1) whether CHF alters the responses mediated by alpha and beta adrenoceptors in small and large peripheral arteries, and 2) the effect of angiotensin-converting enzyme (ACE) inhibition. Rats with CHF (coronary artery ligation) were treated with placebo or the ACE inhibitor lisinopril (10 mg/kg/d) starting 7 days after ligation. Responses to phenylephrine (alpha 1 agonist), salbutamol (beta 2 agonist) as well as acetylcholine (endothelium-dependent), were assessed after 3 months in isolated and pressurized segments of the abdominal aorta, the femoral and the mesenteric arteries. In animals with hemodynamic signs of CHF, neither the vasoconstrictor responses to phenylephrine nor the vasodilator response to salbutamol were affected. In contrast, the dilator response to acetylcholine of both small arteries, but not that of the aorta, was impaired. Furthermore, CHF did not modify vessel structure. While lisinopril did not modify the responses to adrenergic agonists, it normalized the response to acetylcholine. Furthermore, ACE inhibition reduced vascular media cross sectional area and collagen density. Thus, the unchanged arterial responsiveness to adrenoceptor agonists does not indicate any vascular adrenoceptor desensitization, while endothelial dependent vasodilation of small arteries is impaired in CHF. ACE inhibition does not modify the response to adrenergic stimuli, prevents endothelial dysfunction and induces both cardiac and vascular remodeling, which probably contribute to the effect ACE inhibitors have on exercise tolerance and survival.


Assuntos
Inibidores da Enzima Conversora de Angiotensina/farmacologia , Endotélio Vascular/fisiopatologia , Insuficiência Cardíaca/fisiopatologia , Lisinopril/farmacologia , Receptores Adrenérgicos alfa/fisiologia , Receptores Adrenérgicos beta/fisiologia , Acetilcolina/farmacologia , Agonistas alfa-Adrenérgicos/farmacologia , Agonistas Adrenérgicos beta/farmacologia , Albuterol/farmacologia , Animais , Aorta Abdominal/efeitos dos fármacos , Aorta Abdominal/patologia , Aorta Abdominal/fisiopatologia , Doença Crônica , Endotélio Vascular/efeitos dos fármacos , Endotélio Vascular/patologia , Artéria Femoral/efeitos dos fármacos , Artéria Femoral/patologia , Artéria Femoral/fisiopatologia , Insuficiência Cardíaca/patologia , Hemodinâmica/efeitos dos fármacos , Técnicas In Vitro , Masculino , Artérias Mesentéricas/efeitos dos fármacos , Artérias Mesentéricas/patologia , Artérias Mesentéricas/fisiopatologia , Contração Muscular/efeitos dos fármacos , Relaxamento Muscular/efeitos dos fármacos , Neurotransmissores/sangue , Nitroprussiato/farmacologia , Fenilefrina/farmacologia , Ratos , Ratos Wistar , Sistema Renina-Angiotensina/efeitos dos fármacos
6.
Arch Mal Coeur Vaiss ; 87 Spec No 2: 45-50, 1994 Jun.
Artigo em Francês | MEDLINE | ID: mdl-7864722

RESUMO

Treatment with ACE inhibitors has improved the prognosis of cardiac failure (CF). The results of CONSENSUS I, SOLVD and V HEFT II show clinical improvement and longer survival with this therapeutic class of drugs. However, the search for the optimal dosage was not undertaken in these trials (a standard dose was fixed at the onset, average dose of enalapril from 15 to 20 mg/day). In clinical practice, patients are prescribed lower doses of ACE inhibitors (enalapril: 7.5 mg/day) than the averages used in large scale trials. In order to optimise the use of ACE inhibitors, the ATLAS study (Assessment of Treatment with Lisinopril and Survival) was undertaken with the precise objective of comparing two dosages (2.5 to 5 mg/day vs 32.5 to 35 mg/day) of lisinopril on the morbidity and mortality of patients with CF. This international, multicenter, randomised, double-blind parallel group trial aims to include 3,000 patients over 18 years of age with NYHA Classes II, III and IV, and an ejection fraction < or = 30% and to follow them up for 3 to 4.5 years. Nearly 30 French centres will participate in this trial. After an initial, open period of evaluation of tolerance (5 mg to 15 mg/day of lisinopril in France), the patients will be randomised to two groups. After randomisation, all patients will receive 5 mg per day of lisinopril. The "high dose" group will receive 20 mg/day for two weeks, then 30 mg/day in addition to the "open dosage". In cases of intolerance, the dosage may be reduced to 20 mg/day or 10 mg/day, or the drug may be withdrawn.(ABSTRACT TRUNCATED AT 250 WORDS)


Assuntos
Insuficiência Cardíaca/tratamento farmacológico , Lisinopril/uso terapêutico , Protocolos Clínicos , Insuficiência Cardíaca/mortalidade , Humanos , Análise de Sobrevida
7.
Ann Cardiol Angeiol (Paris) ; 53(5): 250-8, 2004 Sep.
Artigo em Francês | MEDLINE | ID: mdl-15532450

RESUMO

OBJECTIVES: Analyse the modalities of preventive therapy of recurrences of paroxysmal or persistent atrial fibrillation (AF) with Vaughan-Williams (VW) type IC antiarrhythmics. METHODS: Observational study conducted with 326 French cardiologists established in general office practice, involving on the one hand an opinion survey among the cardiologists and on the other hand a cross-sectional observatory of usual medical practice. Each cardiologist was asked to include two patients aged less than 65 with non-permanent (paroxysmal or persistent) AF without left ventricle dysfunction (LVD) and initiated on treatment with a VW type IC antiarrhythmic after cardioversion to sinus rhythm. RESULTS: The opinion survey among the cardiologists indicates that non-permanent AF constitutes 36.1% of AF cases, of which 57.8% concern LVD-free patients. Most cardiologists (85%) declare to institute a preventive therapy of AF recurrences in 70-100% of these patients after cardioversion to sinus rhythm, with a VW type IC antiarrhythmic in more than 50% of cases. Of the 633 patients included in the FAUVE observatory, mainly men, 409 (64.6%) had paroxysmal AF and 224 (35.4%) had persistent AF. Analysis of therapeutic management shows that both alteration of the previous treatment and the choice of a VW type IC antiarrhythmic are based chiefly on efficacy and on tolerability of the antiarrhythmic therapy. CONCLUSION: VW type IC antiarrhythmics constitute a therapy of choice for the maintenance of sinus rhythm in non-aged and LVD-free patients with non-permanent AF.


Assuntos
Antiarrítmicos/uso terapêutico , Fibrilação Atrial/prevenção & controle , Cardiologia , Estudos Transversais , Medicina de Família e Comunidade , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Recidiva
8.
J Hypertens Suppl ; 10(5): S37-41, 1992 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-1403232

RESUMO

METHODOLOGY: High-resolution B-mode imaging is a reliable, easily performed and non-invasive means of studying atherosclerosis in superficial blood vessels. Recently it has been used for in vivo studies on the thickness of the common carotid artery wall. It is very sensitive, although the results of practical investigations are highly dependent on both the operator and the direction and angle of ultrasound beams directed towards the vessel. PROTOCOL: We have assessed inter- and intra-observer reproducibility of the measurement of common carotid artery wall thickness in 13 subjects, using two procedures. The first was a standard echographical investigation. In the second procedure, the principal parameters recorded from the first investigation were used to reposition the beam with the same incident angle. RESULTS: Intra-observer variability (correlation coefficient, r = 0.61 for procedure 1 and r = 0.77 for procedure 2) and inter-observer variation (r = 0.58 for procedure 1 and r = 0.71 for procedure 2) were reduced when the second investigation was assisted by reproducibility software. CONCLUSIONS: The proposed method is a reliable and reproducible way of assessing combined intimal and medial wall thickness in the common carotid artery. It may be possible to improve reproducibility using specific software to aid the operator. Since the intimal and medial thickness of the common carotid artery appears to be a sensitive marker of vascular risk, the proposed standardized method of measuring these parameter may allow early detection and assessment of changes.


Assuntos
Artérias Carótidas/diagnóstico por imagem , Interpretação de Imagem Assistida por Computador/métodos , Idoso , Artérias Carótidas/anatomia & histologia , Feminino , Humanos , Masculino , Variações Dependentes do Observador , Reprodutibilidade dos Testes , Software , Ultrassonografia/métodos
9.
Arthritis Care Res (Hoboken) ; 65(9): 1472-81, 2013 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-23554182

RESUMO

OBJECTIVE: To evaluate the performances (sensitivity, specificity, and positive and negative predictive values) at diagnosis and study visit of the Assessment of SpondyloArthritis international Society (ASAS) criteria in axial spondyloarthritis in patients with chronic back pain (CBP). A secondary objective was to identify the most contributory item to diagnosis/classify spondyloarthritis. METHODS: We conducted a multicenter, cross-sectional study. Patients were ages <45 years with a history of CBP and seeing a rheumatologist in France. Data included items from the different sets of criteria, checking if present at diagnosis ("diagnosis")/after diagnosis, but at study visit ("classification"), and the rheumatologist's diagnosis at study visit. Statistical analysis included descriptive characteristics and performances for diagnosis and classification. The diagnosis of the rheumatologist was considered the "gold standard." RESULTS: A total of 1,210 patients were eligible for our analysis. Sensitivity and specificity for ASAS axial criteria were 0.76 and 0.94, respectively, and 0.87 and 0.92 for diagnostic and classification purposes, respectively. The positive likelihood ratio of the ASAS axial criteria was 13.6 and 10.30 for diagnostic and classification purposes, respectively. The most contributory items to diagnosis and classification were radiographic sacroiliitis, followed by magnetic resonance imaging sacroiliitis for diagnosis and history of uveitis for classification. CONCLUSION: We confirm the validity of the ASAS criteria for both diagnostic and classification purposes in a clinical setting of patients with CBP.


Assuntos
Dor nas Costas/diagnóstico , Dor Crônica/diagnóstico , Médicos , Sociedades Médicas/normas , Espondilartrite/classificação , Espondilartrite/diagnóstico , Inquéritos e Questionários/normas , Adulto , Dor nas Costas/terapia , Dor Crônica/terapia , Estudos Transversais , Feminino , Humanos , Internacionalidade , Masculino , Reprodutibilidade dos Testes , Reumatologia/métodos , Reumatologia/normas , Adulto Jovem
10.
Arthritis Care Res (Hoboken) ; 64(6): 919-24, 2012 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-22262475

RESUMO

OBJECTIVE: To accurately estimate the prevalence of and the factors associated with uveitis in spondylarthritis (SpA) patients in France. METHODS: In an observational survey of SpA patients (diagnosis confirmed by the European Spondylarthropathy Study Group and/or Amor's criteria) consulting their rheumatologist for routine followup, we collected information regarding present/past history of uveitis, as well as detailed characteristics of the disease. Factors independently associated with uveitis were determined. RESULTS: From September 2008 to January 2009, 202 rheumatologists participated in the survey and recruited 902 patients (61% men) with a mean ± SD age of 45.3 ± 13.4 years and a mean ± SD disease duration of 10.4 ± 9.6 years. The SpA diagnoses were ankylosing spondylitis (71%), psoriatic arthritis (18%), or other SpA (11%). The HLA-B27 positivity rate was 76%. Uveitis prevalence was 32.2% (95% confidence interval [95% CI] 29.1-35.3%) since psoriasis and inflammatory bowel disease were 22.3% (95% CI 19.5-25.0%) and 8.6% (95% CI 6.7-10.5%), respectively. Recurrence of uveitis occurred in 52.3% and complications occurred in 11.7% of patients. Factors independently associated with uveitis were HLA-B27 positivity (adjusted odds ratio [OR(adj) ] 2.97 [95% CI 1.83-4.81], P < 0.0001) and disease duration (OR(adj) 1.28 [95% CI 1.16-1.41], P < 0.0001 for ≥10 years). CONCLUSION: Results indicate that uveitis is the most common extraarticular feature of SpA, occurring preferentially in HLA-B27-positive patients over the entire course of the disease.


Assuntos
Artrite Psoriásica/epidemiologia , Doenças Inflamatórias Intestinais/epidemiologia , Espondilartrite/epidemiologia , Uveíte/epidemiologia , Adulto , Artrite Psoriásica/imunologia , Comorbidade , Feminino , França/epidemiologia , Antígeno HLA-B27/sangue , Inquéritos Epidemiológicos , Humanos , Doenças Inflamatórias Intestinais/imunologia , Masculino , Pessoa de Meia-Idade , Prevalência , Estudos Retrospectivos , Espondilartrite/imunologia , Uveíte/imunologia
12.
J Chem Ecol ; 31(4): 893-909, 2005 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-16124258

RESUMO

Adult male asparagus flies exhibit typical calling behaviors (suggestive of pheromone production) during which they emit a single volatile compound that was identified as isopropyl (S)-5-hydroxyhexanoate. In laboratory bioassays, synthetic samples elicited an arrestant response in females, but did not appear to attract females. On the other hand, the synthetic material attracted conspecific males in olfactometer bioassays.


Assuntos
Dípteros/química , Óleos Voláteis/isolamento & purificação , Atrativos Sexuais/química , Comportamento Sexual Animal , Fatores Etários , Animais , Bioensaio , Dípteros/fisiologia , Feminino , Hexanóis/isolamento & purificação , Masculino , Atrativos Sexuais/farmacologia , Fatores de Tempo
13.
Bull Entomol Res ; 95(5): 393-9, 2005 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-16197559

RESUMO

The role of various olfactory and visual stimuli was studied in host-plant finding by the asparagus fly Plioreocepta poeciloptera (Schrank), a monophagous monovoltine tephritid causing serious damage to asparagus spears. Volatiles released by asparagus plants were extracted by diethyl ether after cryotrapping concentration, and identified by gas chromatography-mass spectrometry. Twelve of the 13 compounds identified were tested using electroantennography to measure the response of the fly. Behavioural response was analysed using two different flight tunnels according to circadian rhythm, age and sex of adults, presence of the plant and of different coloured lures, presence of a male congener, or exposure to four pure asparagus odour compounds that elicited responses in electroantennography, i.e. hexanal, (E)-2-hexenal, (Z)-2-hexen-1-ol and decanal. Data showed that males locate the host plant more quickly than females. Females are attracted mainly by the blend of plant odour and male pheromone. Both sexes respond to a complex of stimuli only during the afternoon. These findings will be helpful in developing new and effective approaches to control this pest insect.


Assuntos
Asparagus/fisiologia , Asparagus/parasitologia , Tephritidae/fisiologia , Animais , Asparagus/química , Comportamento Animal/fisiologia , Ritmo Circadiano , Feminino , Masculino , Odorantes , Controle Biológico de Vetores , Olfato/fisiologia , Visão Ocular/fisiologia
14.
C R Acad Hebd Seances Acad Sci D ; 281(14): 1039-42, 1975 Oct 06.
Artigo em Francês | MEDLINE | ID: mdl-813872

RESUMO

The leek-moth digs straight mines towards the base of the plant. Experiments show that this orientation would be essentially the consequence of the morphological structure and of the physiological activity of the host-plant while geotactism had little influence on the behaviour of the leaf-miner.


Assuntos
Lepidópteros/fisiologia , Mariposas/fisiologia , Animais , Ecologia , Larva , Locomoção , Fenômenos Fisiológicos Vegetais
15.
C R Acad Hebd Seances Acad Sci D ; 282(14): 1371-4, 1976 Apr 05.
Artigo em Francês | MEDLINE | ID: mdl-820445

RESUMO

In photoperiod and constant temperature, male responsiveness to female pheromones shows a circadian rhythm with a maximum, when females are calling, at the end of scotophase. During photophase, a second peak appears which may correspond in nature with sexual activity at dawn. The sex pheromone production by female seems maximum during scotophase.


Assuntos
Ritmo Circadiano , Lepidópteros/fisiologia , Mariposas/fisiologia , Feromônios/fisiologia , Atrativos Sexuais/fisiologia , Animais , Feminino , Masculino
16.
J Chem Ecol ; 18(11): 1991-2002, 1992 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-24254778

RESUMO

It has been shown previously that sulfur volatiles produced byAllium plants affect the behavior of their specialist phytophages and of their specialist entomophages. The action of these compounds in protecting the leek mothAcrolepiopsis assectella against generalist entomophages was studied in comparison to the proposed original defensive role of these compounds against generalist herbivorous insects. Two ants species,Formica selysi andF. fusca, were used as generalist predators. Six behavioral criteria of the predatory behavior of the ants were studied in presence of the last-instar caterpillars (C5). C5 reared on artificial diets with or without leek components were tested, as well as C5 soaked in frass of leek-reared caterpillars or disulfide solutions. In addition, the response of the ants to pure chemicals found in leek was studied using honey solutions with or without sulfur compounds. The sulfur allelochemicals ofAllium plants have a negative action on predatory ants. Interestingly, the nonvolatile precursors of sulfur volatiles ofAllium plants seem to have a protective role for their phytophagous insects against generalist entomophages.

17.
J Chem Ecol ; 15(6): 1847-54, 1989 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24272187

RESUMO

When crushed, the leek,Allium porrum emits propyl propanethiosulfinate. The unstable thiosulfinate decomposes during GC analysis in numerous compounds, except on very short columns. The propyl propanethiosulfmate is the most attractive substance for the leek moth,ACROLEPIOPSIS ASSECTELLA. This thiosulfinate is not active onPlutella xylostella orPlodia interpunctella and seems to be repulsive onEphestia kuehniella.

18.
J Chem Ecol ; 20(7): 1571-81, 1994 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-24242652

RESUMO

Seven compounds that do not exist in the extracts from legs of males have been isolated in the hair-pencil extracts of maleAcrolepiopsis assectella. By combining techniques of GC-MS and GC-FT-IR, six of these compounds have been identified. They are sixn-alkanes: hexadecane (C16), heptadecane (C17), octadecane (C18), nonadecane (C19), eicosane (C20), and heneicosane (C21). Twelven-alkanes of the homologous series, from the C14-C25 compounds were presented to virgin females, mated females, and males. At the end of the scotophase, four of then-alkanes (C16, C17, C19, C21) present in the hair-pencil extract induced the virgin females to adopt the acceptance posture after having induced the virgin females to remain stationary. The two othern-alkanes (C18 and C20) present in the extract have less effect on the females similar to then-alkanes not present in the males. The blends tested do not seem to indicate any synergy between the most active compounds. The threen-alkanes with an odd number of carbons and the C16 compound would thus be the principle components of the male pheromone ofA. assectella. As well as their role of female aphrodisiac, they tend to make males and fertilized females flee.

19.
J Chem Ecol ; 16(6): 1743-50, 1990 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24263981

RESUMO

Feeding leek moths on an artificial diet has shown that dimethyl and dipropyl disulfides and methyl-propyl disulfide found in frass arise from sulfur compounds specific toAllium. The addition of either propyl or methyl disulfide or their precursors to the diet leads to appearance of the three disulfides in the frass. This implies the transformation of theS-propyl moiety toS-methyl and vice versa by an as yet unknown mechanism.

20.
J Chem Ecol ; 15(4): 1391-8, 1989 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24272020

RESUMO

Acrolepiopsis assectella andPlutella xylostella frass volatiles, trapped on Tenax GC, were examined by capillary gas chromatography. In both moths, the same three disulfides, dimethyl, dipropyl, and methyl propyl, were the most abundant substances, but in different proportions. The synthetic disulfides elicited the same behavioral response by the parasitoid,Diadromus pulchellus as frass. The plant origin of these substances is discussed.

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