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1.
Sci Rep ; 11(1): 5933, 2021 03 15.
Artigo em Inglês | MEDLINE | ID: mdl-33723279

RESUMO

Insect societies require an effective communication system to coordinate members' activities. Although eusocial species primarily use chemical communication to convey information to conspecifics, there is increasing evidence suggesting that vibroacoustic communication plays a significant role in the behavioural contexts of colony life. In this study, we sought to determine whether stridulation can convey information in ant societies. We tested three main hypotheses using the Mediterranean ant Crematogaster scutellaris: (i) stridulation informs about the emitter'caste; (ii) workers can modulate stridulation based on specific needs, such as communicating the profitability of a food resource, or (iii) behavioural contexts. We recorded the stridulations of individuals from the three castes, restrained on a substrate, and the signals emitted by foragers workers feeding on honey drops of various sizes. Signals emitted by workers and sexuates were quantitatively and qualitatively distinct as was stridulation emitted by workers on different honey drops. Comparing across the experimental setups, we demonstrated that signals emitted in different contexts (restraining vs feeding) differed in emission patterns as well as certain parameters (dominant frequency, amplitude, duration of chirp). Our findings suggest that vibrational signaling represents a flexible communication channel paralleling the well-known chemical communication system.


Assuntos
Comunicação Animal , Formigas/fisiologia , Comportamento Animal , Animais , Modelos Teóricos
2.
J Econ Entomol ; 108(3): 1148-55, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-26470240

RESUMO

Drosophila suzukii (Matsumura) is a global pest attacking various berry crops. D. suzukii lays eggs in damaged and in intact wine grape berries of the most soft-skinned varieties. Here, we describe the relative host utilization of different wine grape cultivars grown in Northern Italy and Oregon. Assessments of host berry utilization were performed in both field and laboratory settings. Results were correlated to physiological changes occurring during grape berry development starting at véraison and concluding during harvest. We found that oviposition increased with an increase in sugar content and a decrease of acidity levels. Oviposition increased with a decrease of penetration force. Penetration force, as a measure of skin hardness, is a critical component of host selection among the D. suzukii-exposed cultivars. We demonstrated that incised berries are more favorable for D. suzukii oviposition and as a nutrient substrate. Increased presence on wine grapes, as indicated by egg laying and increased longevity, was observed for flies that were exposed to incised berries as opposed to fully intact berries. D. suzukii flies can be found feeding on damaged wine grapes during the harvest period, especially when the skins of berries are negatively impacted due to cracking, disease, hail injury, and bird damage. Such an increase of feeding and oviposition may increase the likelihood of spoilage bacteria vectoring due to D. suzukii.


Assuntos
Drosophila/fisiologia , Cadeia Alimentar , Vitis/crescimento & desenvolvimento , Agricultura , Animais , Drosophila/crescimento & desenvolvimento , Comportamento Alimentar , Itália , Larva/crescimento & desenvolvimento , Larva/fisiologia , Oregon , Oviposição , Óvulo/crescimento & desenvolvimento , Óvulo/fisiologia , Temperatura , Vitis/genética , Vitis/metabolismo
3.
Bull Entomol Res ; 103(3): 303-9, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23302745

RESUMO

In this paper we describe acoustically the wing-fanning behaviour showed by the male of the braconid Psyttalia concolor towards females and other conspecific males. Psyttalia concolor is a synovigenic koinobiont larval-pupal endoparasitoid of many Tephritidae, used in olive crops to control the olive fruit fly, Bactrocera oleae. In this braconid male wing fanning produces a courtship song characterised by sequences of homogenous pulses with harmonic structure and a fundamental frequency of about 180 Hz. Song parameters can vary according to the behavioural context. Statistically significant differences, both in terms of pulse frequency and duration, characterise fanning towards females in comparison with male-male approaches. Moreover, the pulse duration is associated with the fanning song displayed before a successful courtship. Our observations allowed us to define the airborne component of the sound and to definitely confirm the exclusive role of the wings in signal production within sexual communication in P. concolor.


Assuntos
Comunicação Animal , Comportamento Sexual Animal/fisiologia , Tephritidae/parasitologia , Vespas/fisiologia , Asas de Animais/fisiologia , Animais , Masculino , Espectrografia do Som
4.
J Econ Entomol ; 102(3): 974-80, 2009 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-19610410

RESUMO

The American grapevine leafhopper, Scaphoideus titanus Ball (Hemiptera: Cicadellidae), is the vector of the phytoplasma that causes Flavescence dorée, one of the most threatening grapevine yellows disease. The role of olfaction in host plant detection of this species is still unknown. In this study, the attractiveness of a host plant, the grapevine rootstock Vitis riparia x rupestris 101/14, to nymphs was verified through behavioral bioassays in a vertical glass Y-olfactometer. Furthermore, the olfactory sensitivity to odors extracted from grapevine organs headspace and the external morphology of the antennae were studied by electroantennography (EAG) and scanning electron microscopy (SEM), respectively. Headspace collections were made from fresh apical shoots and leaves. Concentrated extracts were analyzed by coupled gas chromatography and mass spectrometry (GC-MS) to identify volatile compounds. In EAG experiments, weak responses to plant odors were recorded. SEM observations indicated the presence of few antennal sensilla, potentially associated with olfaction. Our results suggest that olfactory cues may play a role in the host plant detection of S. titanus nymphs.


Assuntos
Sinais (Psicologia) , Hemípteros/fisiologia , Extratos Vegetais/química , Olfato/fisiologia , Vitis/química , Animais , Cromatografia Gasosa-Espectrometria de Massas , Microscopia Eletrônica de Varredura , Ninfa/fisiologia , Ninfa/ultraestrutura
5.
Planta Med ; 67(6): 580-4, 2001 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-11509990

RESUMO

The essential oil composition of three Zingiberaceae widely used as medicinal aromatic plants from S. Tomé and Príncipe: Aframomum danielli (Hook. f.) K. Schum., Curcuma longa L. and Zingiber officinale Rosc. was studied. Two samples of the essential oils from fruit of A. danielli and from rhizomes of the other two species, were obtained by hydrodistillation and analyzed by GC, GC-MS, and (13)C-NMR. The essential oil from fruits of A. danielli has been studied for the first time and was characterised by its high content of monoterpenes, with 1,8-cineole (25.5 - 34.4 %) the major constituent, followed by beta-pinene (14.1 - 15.2 %) and alpha-terpineol (9.9 - 12.1 %). Essential oils from the rhizomes of C. longa contained a lower content of ar-turmerone (4.0 - 12.8 %) than those reported in the literature for C. longa from other origins (24.7 - 31.4 %), whereas the results for Z. officinale essential oils were in accordance with the literature data. The essential oils of A. danielli and Z. officinale showed antimicrobial activity against all Gram-positive and Gram-negative bacteria tested, as well as against yeasts and filamentous fungi, using the agar diffusion method.


Assuntos
Anti-Infecciosos/farmacologia , Óleos Voláteis/química , Óleos de Plantas/química , Zingiberaceae/química , Antibacterianos , Bactérias/efeitos dos fármacos , Fungos/efeitos dos fármacos , Óleos Voláteis/farmacologia , Óleos de Plantas/farmacologia , Estruturas Vegetais/química , Plantas Medicinais , Portugal
6.
Am Heart J ; 141(4): 621-9, 2001 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-11275930

RESUMO

BACKGROUND: The outpatient prognostic assessment of coronary artery disease (CAD) by exercise electrocardiography has limitations, including the feasibility of the test and its low positive predictive value in several clinical conditions. In the current study we investigated the safety, feasibility, and prognostic value of pharmacologic stress echocardiography in a large cohort of ambulatory patients. METHODS: The study group was made of 1482 ambulatory patients (969 men, aged 60 +/- 10 years) who underwent stress echocardiography with either dipyridamole (n = 846) or dobutamine (n = 636) for evaluation of suspected or known stable CAD. The pretest likelihood of CAD was intermediate (<70%) in 709 patients and high (> or =70%) in 773 patients. RESULTS: There was no complication during the dipyridamole test, whereas 2 ischemia-dependent, sustained ventricular tachycardias occurred during the dobutamine test. Limiting side effects were observed in 2% of dipyridamole and in 3% of dobutamine stresses. The echocardiogram was positive in 459 patients. During a mean follow-up of 28 +/- 24 months, 58 patients died, 33 had a nonfatal myocardial infarction, and 158 underwent early (< or =3 months) and 64 late (>3 months) revascularization. Multivariate predictors of hard events (death, infarction) were positive echocardiographic results (hazard ratio [HR] 2.9) and resting wall motion score index (WMSI) (HR 2.3). In considering major events (death, infarction, late revascularization) as end points, positive echocardiographic result (HR 4.3), scar (HR 2.2), and resting WMSI (HR 1.7) were independent prognostic predictors. The 5-year survival rates for the ischemic and nonischemic groups were, respectively, 80% and 91% (HR 3.6, 95% confidence interval [CI] 3.8-8.4; P <.0001) considering hard cardiac events and 65% and 88% (HR 2.6, 95% CI 2.1-5.9; P <.0001) considering major events. Multivariate predictors of major events were positive echocardiographic results (HR 8.2) and male sex (HR 2.5) for the intermediate-risk group and positive echocardiographic results (HR 2.9), resting WMSI (HR 1.8), and prior Q-wave myocardial infarction (HR 1.8) for the high-risk group. CONCLUSIONS: Pharmacologic stress echocardiography is safe, highly feasible, and effective in prognostic assessment of ambulatory patients when both a general population and groups selected on the basis of pretest likelihood of CAD are analyzed. It represents a valid complementary tool to exercise electrocardiography for prognostic purposes in outpatients.


Assuntos
Doença das Coronárias/diagnóstico por imagem , Assistência Ambulatorial , Dipiridamol , Dobutamina , Eletrocardiografia , Teste de Esforço , Estudos de Viabilidade , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Prognóstico , Fatores de Risco , Ultrassonografia , Vasodilatadores
7.
Ital Heart J ; 1(1): 45-9, 2000 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-10868923

RESUMO

BACKGROUND: The aim of this study was to assess the prevalence of pericardial effusion in acute myocardial infarction and the different prognosis associated with distinct patterns of pericardial effusion (anechoic/hypoechoic vs hyperechoic effusion). METHODS: Five hundred eighty-five consecutive patients admitted to the Coronary Care Unit for acute myocardial infarction were initially considered. Forty of them were excluded due to a technically poor acoustic window. The remaining 545 patients were studied by two-dimensional echocardiography at admission, before discharge (after an average of 9 days in the Coronary Care Unit) and whenever there was an important change in the clinical status (chest pain, lipothymia or syncope, hemodynamic deterioration with systolic blood pressure < 90 mmHg, cardiac arrest). RESULTS: Pericardial effusion was found in 51 patients (9%). Three distinct textural patterns of pericardial effusion were noted on the basis of the echogenic properties: 1) anechoic or hypoechoic pericardial effusion was frequent (30 patients), mild or moderate and generally benign; 2) hyperechoic type "A" effusion pattern was rare (2 patients) and associated with fever, leukocytosis and pericardial rubs; 3) hyperechoic type "B" was frequent (19 patients), large and always associated with major complications (all cases cardiac tamponade and/or death). CONCLUSIONS: Pericardial effusion is not an uncommon finding in serial echo evaluation of patients with acute myocardial infarction, especially when infarction is anterior, extensive and Q wave. Echocardiographically detected pericardial effusion shows different textural patterns with hypoanechoic effusion more frequent, limited and prognostically benign than hyperechoic effusion larger and often associated with adverse events.


Assuntos
Infarto do Miocárdio/diagnóstico por imagem , Derrame Pericárdico/diagnóstico por imagem , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Infarto do Miocárdio/complicações , Derrame Pericárdico/etiologia , Prognóstico , Terapia Trombolítica , Ultrassonografia
9.
J Nucl Cardiol ; 5(1): 19-27, 1998.
Artigo em Inglês | MEDLINE | ID: mdl-9504869

RESUMO

BACKGROUND: To overcome the relatively low accuracy of exercise stress testing (EST) in detecting coronary artery disease (CAD), both echocardiography and perfusion scintigraphy have been evaluated in conjunction with pharmacologic stress, but there is still uncertainty of the relative value of these tests as possible first-line examinations for suspected CAD. This study evaluated the accuracy of EST, dipyridamole and dobutamine stress echocardiography (DIP-ECHO, DOB-ECHO), and dipyridamole and dobutamine technetium 99m sestamibi tomography (DIP-MIBI, DOB-MIBI) for the detection of CAD in patients evaluated for the first time because of chest pain. METHODS AND RESULTS: Sixty patients underwent EST, DIP-ECHO, DOB-ECHO, DIP-MIBI, and DOB-MIBI. Echocardiographic images were acquired simultaneously with sestamibi injections, and the scintigraphic images were collected 1 hour later. Coronary angiography was performed within 15 days. Out of 33 patients with significant (>70%) coronary stenoses, 19 (58%) were correctly identified by EST, 18 (55%) by DIP-ECHO, 20 (61%) by DOB-ECHO, 32 (97%) by DIP-MIBI, and 30 (91%) by DOB-MIBI (p < 0.005 for MIBI vs EST and ECHO). The specificity of EST was 67% (p < 0.05 vs ECHO and MIBI), 96%, 96%, 89%, and 81%, respectively. Of the 62 stenotic coronary arteries, 20 (32%) were correctly identified by DIP-ECHO, 24 (39%) by DOB-ECHO, 48 (77%) by DIP-MIBI, and 45 (73%) by DOB-MIBI. The sensitivity of the imaging techniques in predicting the presence of multivessel disease was 14% and 29% for DIP and DOB-ECHO compared with 48% and 57% for DIP and DOB-MIBI. CONCLUSIONS: Our results confirm the limited reliability of EST in detecting CAD and the good diagnostic value of DIP and DOB-MIBI. Conversely, the lower sensitivity and the poorer capability to recognize multivessel CAD do not support the role of either DIP or DOB-ECHO as first-line examination for suspected CAD.


Assuntos
Dor no Peito/etiologia , Doença das Coronárias/diagnóstico , Ecocardiografia/métodos , Teste de Esforço , Tomografia Computadorizada de Emissão de Fóton Único , Angiografia Coronária , Dipiridamol , Dobutamina , Eletrocardiografia , Estudos de Avaliação como Assunto , Humanos , Variações Dependentes do Observador , Estudos Prospectivos , Sensibilidade e Especificidade , Tecnécio Tc 99m Sestamibi
10.
G Ital Cardiol ; 25(9): 1153-9, 1995 Sep.
Artigo em Italiano | MEDLINE | ID: mdl-8529852

RESUMO

BACKGROUND: Mitral valve prolapse (MVP) is generally regarded as a benign condition, but serious complications (including severe mitral insufficiency, cerebral ischemia, infective endocarditis, complex arrhythmias and sudden death) have been described in a minority of patients and have been correlated to demographic, clinical and echocardiographic characteristics. Both a lack of standardized definition of MVP in earlier studies and the different ways of recruitment of MVP patients may explain the variability in reported complication rates. METHODS: As an offspring of a larger prospective study this paper focuses on the profile of patients who were found to have MVP by M-Mode and two-dimensional echocardiography in several outpatient hospital departments. A total of 8252 consecutive subjects, examined since March 1990 to February 1991 in the Echo laboratories of the Florence area are considered; according to the presence or absence of structural changes (anterior mitral leaflet thickness > 5 mm, leaflet redundancy and/or anulus dilatation) two groups of patients with MVP (A and B) were identified. RESULTS: A MVP was diagnosed in 288 subjects (3.5%), 170 females (59%) and 118 males (41%), mean age 41 +/- 18 years (range 7-84). 110 (38%) were in Group A, 178 (62%) in Group B. The following parameters differed significantly in the two groups: age (45 +/- 17 vs 39 +/- 17 years; p < 0.003); male gender (50% vs 35%; p < 0.01); auscultatory findings (midsystolic click: 31% vs 68%; p < 0.00001; holosystolic murmur: 22% vs 3%; p < 0.00001); left ventricular diameter (53 +/- 7 vs 48 +/- 5 mm; p < 0.00001) and left atrial diameter (38 +/- 8 vs 33 +/- 5 mm; p < 0.00001). Among patients with mitral regurgitation detected by Color Doppler Echocardiography 65% were in Group A (p < 0.00001). CONCLUSIONS: These patients with MVP are obviously selected by the modality of recruitment; hence there is a higher prevalence of subjects with morphologic abnormalities and mitral regurgitation who are older and more likely to be male if compared to individuals with MVP who are found in the general population. A long-term follow-up of these patients is ongoing: owing to the data of the literature about prognostic predictors, a higher incidence of complications with a different prognosis between the two groups (with or without structural changes of the mitral valve) is expected.


Assuntos
Ecocardiografia , Prolapso da Valva Mitral/diagnóstico por imagem , Pacientes Ambulatoriais , Adulto , Distribuição por Idade , Distribuição de Qui-Quadrado , Feminino , Seguimentos , Humanos , Itália/epidemiologia , Masculino , Pessoa de Meia-Idade , Prolapso da Valva Mitral/epidemiologia , Prevalência , Prognóstico , Estudos Prospectivos , Distribuição por Sexo
11.
Am J Cardiol ; 73(7): 450-5, 1994 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-8141085

RESUMO

From a population of 2,698 patients (579 evaluated early after an uncomplicated acute myocardial infarction) who underwent dipyridamole echocardiography testing (DET) and subsequent coronary angiography, left main (LM) stenosis > or = 50% was present in 73 (61 men and 12 women, mean age 62 +/- 8 years). These 73 patients were compared with a control group comprising 100 consecutive coronary patients without LM disease. Both groups were similar regarding mean age, sex, incidence of previous myocardial infarction, left ventricular function at rest, and severity of coronary artery disease by the number of diseased vessels excluding the LM. The proportion of patients receiving antianginal therapy during DET was higher in the LM than in the non-LM group (32 vs 14%; p < 0.01). No major complication (severe hypotension, sustained arrhythmia, myocardial infarction or death) occurred during DET. Of 73 patients with LM disease, 68 had positive DET (sensitivity 93%), dipyridamole time was 7.1 +/- 3.8 minutes, and the rest-peak stress variation in dipyridamole wall motion score index (1 = normal to 4 = dyskinesia, in an 11-segment model) was 0.37 +/- 0.23; 14 patients (19%) were resistant to aminophylline and needed nitrates to resolve ischemia. In the non-LM group, DET was positive in 72% (p < 0.001 vs LM), with a longer dipyridamole time (9.6 +/- 5.2 minutes; p < 0.001 vs LM), lower rest-peak stress wall motion score index variation (0.29 +/- 0.25; p < 0.05 vs LM), and less frequent antidote resistance (1%; p < 0.001 vs LM).(ABSTRACT TRUNCATED AT 250 WORDS)


Assuntos
Doença das Coronárias/diagnóstico por imagem , Dipiridamol , Ecocardiografia/métodos , Idoso , Análise de Variância , Distribuição de Qui-Quadrado , Angiografia Coronária , Estudos de Viabilidade , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Sensibilidade e Especificidade
12.
G Ital Cardiol ; 23(11): 1155-64, 1993 Nov.
Artigo em Italiano | MEDLINE | ID: mdl-8163106

RESUMO

Of 554 patients hospitalized for acute myocardial infarction, 61 (11%) died in the Intensive Care Unit. Echocardiography (performed at admission, at discharge and in every case of modification of the clinical course) allowed the diagnosis of left ventricular free wall rupture (RPLVS) in 20. The clinical course was acute in 13 of the latter, presenting with electromechanical dissociation (DEM). Pericardiocentesis allowed survival of one patient of this group. In 6 patients RPLVS had a subacute pattern, with progressive hypotension (in 2 cases preceded by syncope): pericardiocentesis allowed temporary stabilization of 4 patients; 2 had surgical repair with 1 long-term survivor. In 1 patient RPLVS began with lipothymia, and then he stabilised spontaneously. Many physiopathological mechanisms are discussed which could explain the great clinical variability of RPLVS. Awareness that RPLVS can appear with patterns different from DEM is fundamental for the diagnosis of subacute RPLVS. Indeed, this form of RPLVS, when recognized, can be treated with an encouraging prognosis.


Assuntos
Ruptura Cardíaca Pós-Infarto/epidemiologia , Idoso , Idoso de 80 Anos ou mais , Diagnóstico Diferencial , Emergências , Feminino , Ruptura Cardíaca Pós-Infarto/diagnóstico , Ruptura Cardíaca Pós-Infarto/mortalidade , Ventrículos do Coração , Humanos , Incidência , Masculino , Pessoa de Meia-Idade , Prognóstico
13.
G Ital Cardiol ; 22(7): 863-7, 1992 Jul.
Artigo em Italiano | MEDLINE | ID: mdl-1473662

RESUMO

A case of an undetected myocardial infarction in a patient with diabetes mellitus in which the first clinical sign was a syncope due to rupture of the left ventricular inferior wall is described. Survival was enhanced by a fast diagnosis (aided by the availability of an ECO 2D in the emergency room), by emergency pericardiocentesis with temporary haemodynamic stabilization and by prompt access to the Cardiosurgical Unit. A prompt diagnosis and treatment can allow the survival of patients, even in the extreme case that the ventricular wall rupture represents the first clinical manifestation of the myocardial infarction. The left ventricular free wall rupture in the course of myocardial infarction has a subacute pattern in about 30%, due to various mechanisms such as thrombosis or pericardial adherence over the ruptured wall.


Assuntos
Ruptura Cardíaca Pós-Infarto/diagnóstico , Angiografia Coronária , Ecocardiografia , Eletrocardiografia , Emergências , Ruptura Cardíaca Pós-Infarto/patologia , Ruptura Cardíaca Pós-Infarto/cirurgia , Ventrículos do Coração/patologia , Ventrículos do Coração/cirurgia , Humanos , Masculino , Pessoa de Meia-Idade , Síncope/diagnóstico
14.
G Ital Cardiol ; 20(8): 738-41, 1990 Aug.
Artigo em Italiano | MEDLINE | ID: mdl-2272422

RESUMO

Two-dimensional echocardiography is the chosen method for the detection of mobile right atrial masses. In this report we describe a case of pulmonary and paradoxical embolism in which 2D echocardiography was useful for the detection of a thromboembolus entrapped in the patent foramen ovale. The right and left atrial thromboembolus was removed surgically with success.


Assuntos
Cardiopatias , Comunicação Interatrial/complicações , Embolia Pulmonar/etiologia , Tromboembolia , Adulto , Ecocardiografia , Emergências , Átrios do Coração , Cardiopatias/diagnóstico , Cardiopatias/cirurgia , Humanos , Masculino , Tromboembolia/diagnóstico , Tromboembolia/cirurgia
15.
G Ital Cardiol ; 20(7): 636-8, 1990 Jul.
Artigo em Italiano | MEDLINE | ID: mdl-2245902

RESUMO

We describe a case of left ventricular intramyocardial lipoma in a patient with diffuse subcutaneous lipomatosis. The diagnosis was suspected on the basis of a two-dimensional echocardiographic examination that revealed a hyperechogenic mass within the left ventricular wall. Magnetic resonance imaging showed a homogeneous high signal mass thus indicating the presence of a benign lipoma. This report shows the ability of two-dimensional echocardiography and magnetic resonances imaging in detecting, localizing and characterizing left ventricular lipomas without the use of more invasive studies.


Assuntos
Neoplasias Cardíacas/diagnóstico , Lipoma/diagnóstico , Lipomatose/diagnóstico , Imageamento por Ressonância Magnética , Neoplasias Cutâneas/diagnóstico , Ecocardiografia , Ventrículos do Coração/diagnóstico por imagem , Ventrículos do Coração/patologia , Humanos , Masculino , Pessoa de Meia-Idade
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