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1.
Neotrop Entomol ; 52(5): 921-931, 2023 Oct.
Article in English | MEDLINE | ID: mdl-37584879

ABSTRACT

Tetrastichus howardi (Olliff) (Hymenoptera: Eulophidae) parasitizes the diamond back moth Plutella xylostella (L.) (Lepidoptera: Plutellidae), but not much is known about its potential as a biocontrol agent. A rearing protocol has been established for this parasitoid on pupae of the factitious host Tenebrio molitor (L.) (Coleoptera: Tenebrionidae), with the aim of releasing it in the field to manage several lepidopteran species. The potential population growth of a parasitoid can be measured through fertility life tables and provide supporting information for using T. howardi in the management of P. xylostella. Also, the fitness and behavior of T. howardi reared on a factitious host can be indicators of its potential to control P. xylostella. Thus, in this study, the fertility life table parameters of T. howardi parasitizing P. xylostella were determined, as well as the effects of the natal host on the behavior of T. howardi towards host volatiles and parasitism rate. The results showed that net reproduction rate (Ro) and the intrinsic rate of population growth (rm) of T. howardi parasitizing P. xylostella were 13.6 (♀/♀) and 0.124 (♀/♀*day), respectively, whereas the mean generation time was 20.9 days. Moreover, the natal host (T. molitor or P. xylostella) did not affect the fitness, parasitism rate, or olfactory response of T. howardi. In general, regardless of the natal host, parasitoid females responded to volatiles of both host species and exhibited the same rate of parasitism on P. xylostella. Therefore, T. howardi reared on the factitious host maintains its attraction and potential to parasitize P. xylostella, and can contribute to the biological control of this pest.


Subject(s)
Coleoptera , Hymenoptera , Moths , Tenebrio , Female , Animals , Hymenoptera/physiology , Life Tables , Smell , Fertility , Larva
3.
J Econ Entomol ; 112(5): 2222-2228, 2019 09 23.
Article in English | MEDLINE | ID: mdl-31216009

ABSTRACT

Immature stages of the boll weevil, Anthonomus grandis grandis Boh. (Coleoptera: Curculionidae), develop protected inside cotton fruiting structures. Therefore, the adult beetles have become the main target of insecticide applications. The use of insect growth regulators (IGRs) is recommended against immatures, even though they may also affect the survival and reproductive traits of adult insects. The present study evaluated the impact of a juvenile hormone analog (pyriproxyfen), an ecdysteroid agonist (methoxyfenozide), and a chitin biosynthesis inhibitor (lufenuron) on adult cotton boll weevils, a key cotton pest. Mated and virgin beetles were treated by feeding them contaminated squares and cotton leaf discs that were previously immersed into pyriproxyfen, methoxyfenozide, and lufenuron solutions at field-rate concentrations. After exposure, treated couples were caged onto cotton plants, and survival, fecundity, and egg viability were evaluated. The IGRs neither affected the survival nor fecundity of adult boll weevils. On the other hand, egg viability was significantly reduced by lufenuron, regardless of whether the females were treated premating or postmating or whether their pairs were either treated or untreated. However, egg viability increased as the females aged since the initial exposure date to lufenuron, indicating a potential transovarial effect of this insecticide. Our results indicate that pyriproxyfen and methoxyfenozide do not affect adult boll weevils, whereas lufenuron temporarily reduces the egg viability of this key cotton pest.


Subject(s)
Coleoptera , Insecticides , Weevils , Animals , Female , Gossypium , Juvenile Hormones , Reproduction
4.
J Strength Cond Res ; 32(5): 1462-1470, 2018 May.
Article in English | MEDLINE | ID: mdl-28723813

ABSTRACT

Trevizani, GA, Seixas, MB, Benchimol-Barbosa, PR, Vianna, JM, da Silva, LP, and Nadal, J. Effect of resistance training on blood pressure and autonomic responses in treated hypertensives. J Strength Cond Res 32(5): 1462-1470, 2018-This study evaluated the effect of resistance training (RT) on heart rate variability (HRV) and on blood pressure (BP) responses to acute and short-term exposure in treated hypertensive (HT) subjects. Twenty-one men participated in the study, 8 HT under drug treatment regimen and achieving adequate BP control before inclusion and 13 normotensive (NT). The RT protocol consisted of 12 sessions with eight exercises (leg extension, leg press, leg curl, bench press, seated row, triceps push-down, seated calf flexion, and seated arm curl) performed for two sets of 15-20 repetitions with 50% of one repetition maximum with 2-minute rest intervals in between sets, 3×/week. Heartbeat measurements were taken before and after RT, and BP was measured at the beginning and at the end of each session after 10-minute rest. The repeated measures analysis of variance (effect: group vs. training) evaluated BP and HRV responses. Effect size (ES) calculation measured the magnitude of the RT effect on these variables. There was a statistically significant reduction in postexercise systolic BP in both groups (p = 0.040), without significant change in resting BP along RT (p = 0.159). Regarding HRV, it was observed a reduced sympathetic-vagal balance (training interaction vs. group: p = 0.058, ES = -0.83) in HT subjects. Resistance training promotes a significant acute reduction of BP in the HT and NT groups and provides a slight benefit of cardiac autonomic balance in the HT.


Subject(s)
Autonomic Nervous System/physiology , Hypertension/physiopathology , Hypertension/therapy , Resistance Training/methods , Aged , Antihypertensive Agents/therapeutic use , Blood Pressure/physiology , Heart Rate/physiology , Humans , Hypertension/drug therapy , Male , Middle Aged , Muscle, Skeletal/physiology , Rest/physiology , Vagus Nerve/physiology
5.
Ecotoxicol Environ Saf ; 147: 963-971, 2018 Jan.
Article in English | MEDLINE | ID: mdl-29029382

ABSTRACT

Broad-spectrum insecticides may disrupt biological control and cause pest resurgence due to their negative impacts on natural enemies. The preservation of sustainable pest control in agroecosystems requires parallel assessments of insecticide toxicity to target pests and their key natural enemies. In the present study, the leaf dipping method was used to evaluate the relative toxicity of six insecticides to the striped mealybug, Ferrisia dasylirii (Cockerell) (Hemiptera: Pseudococcidae) and its predator, Tenuisvalvae notata (Mulsant) (Coleoptera: Coccinellidae). Three neurotoxic insecticides, lambda-cyhalothrin, methidathion and thiamethoxam, caused complete mortality of both pest and predator when applied at their highest field rates. In contrast, lufenuron, pymetrozine and pyriproxyfen caused moderate mortality of third-instar mealybug nymphs, and exhibited low or no toxicity to either larvae or adults of the lady beetle. At field rates, lufenuron and pymetrozine had negligible effects on prey consumption, development or reproduction of T. notata, but adults failed to emerge from pupae when fourth instar larvae were exposed to pyriproxyfen. In addition, pyriproxyfen caused temporary sterility; T. notata females laid non-viable eggs for three days after exposure, but recovered egg fertility thereafter. Our results indicate that the three neurotoxic insecticides can potentially control F. dasylirii, but are hazardous to its natural predator. In contrast, lufenuron and pymetrozine appear compatible with T. notata, although they appear less effective against the mealybug. Although the acute toxicity of pyriproxyfen to T. notata was low, some pupal mortality and reduced egg fertility suggest that this material could impede the predator's numerical response to mealybug populations.


Subject(s)
Coleoptera/drug effects , Environmental Pollutants/toxicity , Hemiptera/drug effects , Insecticides/toxicity , Pest Control, Biological , Animals , Brazil , Coleoptera/growth & development , Female , Gossypium/parasitology , Hemiptera/growth & development , Insecticides/pharmacology , Larva/drug effects , Larva/growth & development , Nymph/drug effects , Nymph/growth & development , Predatory Behavior/drug effects , Pupa/drug effects , Pupa/growth & development , Reproduction/drug effects
6.
Behav Processes ; 144: 93-99, 2017 Nov.
Article in English | MEDLINE | ID: mdl-28941797

ABSTRACT

The ladybird beetle Tenuisvalvae notata is an important predator of mealybugs (Pseudococcidae); however, little is known about its reproductive behavior. Thus, in order to improve methods of its rearing, this work studied several aspects regarding the sexual behavior of T. notata. We investigated its sexual activity period, age of the first copulation, mating frequency over 24h, and oviposition during a 30-day interval. Sexual activity of T. notata is diurnal with peak between 1100h and 1500h. Males need about 4days to first copulation, whereas females can mate at emergence. Adults mate 1.17±0.16-1.91±0.29 times over 24h with an average duration of 84±19.70s (ranging from 27 to 130s) per mating. Females produced an average of 54±6.42-64±7.08 offspring over 30days. An ethogram was also constructed to depict the events that occurred during copulation as follows: the male mounts the female, inserts the aedeagus, touches its back with palps and mandibles, and attempts to hold it simultaneously. The female can walk while copulating or remains motionless; the male retracts its aedeagus and twists on the females' back before moving apart.


Subject(s)
Coleoptera , Oviposition/physiology , Sexual Behavior, Animal/physiology , Animals , Copulation/physiology , Female , Male , Reproduction
7.
Ecotoxicology ; 26(5): 589-599, 2017 Jul.
Article in English | MEDLINE | ID: mdl-28357620

ABSTRACT

Recent widespread infestations of the invasive sugarcane aphid, Melanaphis sacchari (Zehntner) (Hemiptera: Aphididae), in sorghum fields in the southern USA have created demand for insecticides that will provide effective control of sugarcane aphid, while conserving those beneficial species that contribute to biological control of the pest. We tested the susceptibility of both adult and immature stages of two aphid predators, the green lacewing, Chrysoperla carnea (Stephens) (Neuroptera: Chrysopidae), and the insidious flower bug, Orius insidiosus (Say) (Hemiptera: Anthocoridae), to three aphicides, flonicamid, sulfoxaflor and flupyradifurone. Flonicamid was innocuous to both species regardless of life stage or route of exposure. Lacewing adults were more susceptible to sulfoxaflor and flupyradifurone than were larvae, and had higher mortality when fed contaminated honey solution than when contacting residues on an inert surface. When laid in sunflower stems treated with these two materials, eggs of O. insidiosus hatched successfully, but nymphs experienced significant mortality when exposed to treated stems, likely due to phytophagous behavior that resulted in some insecticide ingestion. Despite these impacts, we conclude that both sulfoxaflor and flupyradifurone are likely to be relatively innocuous in comparison to more broad-spectrum insecticides and are thus potentially compatible with biological control and overall management of M. sacchari in grain sorghum.


Subject(s)
Insecta/physiology , Insecticides/toxicity , Animals , Aphids/physiology , Hemiptera/physiology , Heteroptera , Larva , Nymph , Predatory Behavior/drug effects , Toxicity Tests
8.
Environ Entomol ; 45(6): 1398-1403, 2016 12.
Article in English | MEDLINE | ID: mdl-28028086

ABSTRACT

Nonconsumptive effects of predators on prey are well known, but similar effects among competing predators are not. Aphidophagous insect larvae are notorious for cannibalism and intraguild predation, as they compete for aggregated but ephemeral prey. We tested for indirect effects of competitors on the development of Coleomegilla maculata DeGeer and Hippodamia convergens Guerin-Meneville (Coleoptera: Coccinellidae), and a green lacewing, Chrysoperla carnea Stephens (Neuroptera: Chrysopidae), with all larvae reared on eggs of Ephestia kuehniella Zeller (Lepidoptera: Pyralidae). Control larvae were reared singly, while treatment larvae were reared pairwise, with either a conspecific or heterospecific, in partitioned Petri dishes that allowed the passage of chemical cues. Larvae of C. maculata, a dietary generalist, appeared stressed by the presence of competing larvae, whether con- or heterospecific, and suffered fitness costs (longer pupation times, lower male adult mass). In contrast, H. convergens and C. carnea, both aphid specialists, responded to competing larvae with accelerated development, and without any apparent costs in terms of adult size or reproductive performance. Adult C. carnea in some treatments were heavier than solitary controls, suggesting a higher consumption rate by the induced phenotype, and those exposed to H. convergens began oviposition earlier. Thus, the phenotypes induced in the specialized aphid predators were adaptive for development in aphid colonies, whereas that induced in the generalist was not. These results indicate that nonconsumptive effects are not simply a vertical force acting on prey, but can also impact conspecific and heterospecific competitors on the same trophic level.


Subject(s)
Insecta/physiology , Predatory Behavior , Adaptation, Biological , Animals , Cannibalism , Coleoptera/growth & development , Coleoptera/physiology , Competitive Behavior , Female , Insecta/growth & development , Larva/growth & development , Larva/physiology , Male
9.
Chemosphere ; 159: 1-9, 2016 Sep.
Article in English | MEDLINE | ID: mdl-27266835

ABSTRACT

Insecticide resistance is usually associated with pests, but may also evolve in natural enemies. In this study, adult beetles of three distinct North American populations of Hippodamia convergens Guérin-Méneville, and the progeny of reciprocal crosses between the resistant and most susceptible population, were treated topically with varying concentrations of lambda-cyhalothrin and dicrotophos. In addition, the LD50s of both insecticides were applied in combination to resistant individuals. The developmental and reproductive performance of each population was assessed in the absence of insecticide exposure to compare baseline fitness. California and Kansas populations were susceptible to both materials, whereas Georgia (GA) beetles exhibited a resistance ratio (RR50) of 158 to lambda-cyhalothrin and 530 to dicrotophos. Inheritance of lambda-cyhalothrin resistance was X-linked, whereas inheritance of dicrotophos resistance was autosomal. Mortality of resistant beetles treated with a mixture of LD50s of both materials was twice that of those treated with lambda-cyhalothrin alone, but not significantly different from those receiving dicrotophos alone. Life history parameters were largely similar among populations, except that Georgia beetles had higher egg fertility relative to susceptible populations. We conclude that the high levels of resistance to lambda-cyhalothrin and dicrotophos in Georgia beetles reflect heavy loads of these insecticides in local environments, most likely the large acreage under intensive cotton cultivation.


Subject(s)
Coleoptera/drug effects , Insecticide Resistance , Insecticides/toxicity , Nitriles/toxicity , Organophosphorus Compounds/toxicity , Pyrethrins/toxicity , Animals , California , Coleoptera/physiology , Female , Fertility/drug effects , Georgia , Kansas , Male
10.
Clin Physiol Funct Imaging ; 36(4): 269-73, 2016 Jul.
Article in English | MEDLINE | ID: mdl-25532598

ABSTRACT

The purpose of this study was to investigate the application of the principal component analysis (PCA) technique on power spectral density function (PSD) of consecutive normal RR intervals (iRR) aiming at assessing its ability to discriminate healthy women according to age groups: young group (20-25 year-old) and middle-aged group (40-60 year-old). Thirty healthy and non-smoking female volunteers were investigated (13 young [mean ± SD (median): 22·8 ± 0·9 years (23·0)] and 17 Middle-aged [51·7 ± 5·3 years (50·0)]). The iRR sequence was collected during ten minutes, breathing spontaneously, in supine position and in the morning, using a heart rate monitor. After selecting an iRR segment (5 min) with the smallest variance, an auto regressive model was used to estimate the PSD. Five principal component coefficients, extracted from PSD signals, were retained for analysis according to the Mahalanobis distance classifier. A threshold established by logistic regression allowed the separation of the groups with 100% specificity, 83·2% sensitivity and 93·3% total accuracy. The PCA appropriately classified two groups of women in relation to age (young and Middle-aged) based on PSD analysis of consecutive normal RR intervals.


Subject(s)
Aging , Autonomic Nervous System/physiology , Electrocardiography/methods , Heart Rate , Heart/innervation , Signal Processing, Computer-Assisted , Adult , Age Factors , Female , Healthy Volunteers , Humans , Middle Aged , Predictive Value of Tests , Principal Component Analysis , Sex Factors , Supine Position , Time Factors , Young Adult
14.
Arq Bras Cardiol ; 94(2): 262; author reply 262-3, 280; author reply 280-1, 267; author reply 267-8, 2010 Feb.
Article in English, Portuguese, Spanish | MEDLINE | ID: mdl-20428626
15.
Metab Brain Dis ; 25(2): 219-25, 2010 Jun.
Article in English | MEDLINE | ID: mdl-20424907

ABSTRACT

We evaluated the activities of mitochondrial respiratory chain complexes in the brain of rats after renal ischemia and the effect of administration of the antioxidants N-acetylcysteine (NAC) and deferoxamine (DFX). The rats were divided into the groups: sham (control) or renal ischemia treated with saline, NAC 20 mg/kg, DFX 20 mg/kg or both antioxidants. Complex I activity was inhibited in hippocampus, striatum, prefrontal cortex and cerebral cortex of rats 1 and 6 h after renal ischemia and that the treatment with a combination of NAC and DFX prevented such effect. Complex I activity was not altered in hippocampus, striatum, prefrontal cortex and cerebral cortex of rats 12 h after renal ischemia. Complexes II and III activities were not altered in hippocampus, striatum, prefrontal cortex and cerebral cortex of rats 1, 6 and 12 h after renal ischemia. Complex IV activity was inhibited in hippocampus, striatum, prefrontal cortex and cerebral cortex of rats 1 h after renal ischemia, but the treatment with the combination of NAC and DFX was able to prevent this inhibition. Complex IV activity was not altered in hippocampus, striatum, prefrontal cortex and cerebral cortex of rats 6 and 12 h after renal ischemia. These results suggest that the inhibition of mitochondrial respiratory chain after renal ischemia might play a role in the pathogenesis of uremic encephalopathy.


Subject(s)
Acetylcysteine/pharmacology , Deferoxamine/pharmacology , Electron Transport Complex I/drug effects , Electron Transport/drug effects , Ischemia/metabolism , Ischemia/prevention & control , Kidney Diseases/metabolism , Kidney Diseases/prevention & control , Animals , Cell Respiration/drug effects , Cell Respiration/physiology , Disease Models, Animal , Drug Combinations , Drug Synergism , Electron Transport/physiology , Electron Transport Complex I/metabolism , Free Radical Scavengers/pharmacology , Ischemia/etiology , Kidney Diseases/complications , Male , Rats , Rats, Wistar
18.
Int J Cardiol ; 141(2): 203-4, 2010 May 28.
Article in English | MEDLINE | ID: mdl-19135736

ABSTRACT

In 2006, Brazilian government received the international certificate of interruption of the vectorial transmission of Chagas' disease. However, outbreaks reported in Brazilian Amazon rainforest bear a regular occurrence and represents a relevant regional epidemiological gauge. The wild life cycle of the Chagas' disease transmission (i.e., triatomine-marsupial cycle) is present outside the previously reported endemic belt, ubiquitously, as infective triatomines can be demonstrated in Palm trees widespread all over the Amazon rainforest. As humans invade the rainforest, one is incidentally caught up and further becomes' an active part of American trypanosomiasis wild life cycle.


Subject(s)
Chagas Disease/transmission , Animals , Brazil/epidemiology , Chagas Disease/epidemiology , Disease Outbreaks , Endemic Diseases , Humans , Insect Vectors
20.
Int J Cardiol ; 133(2): 275-7, 2009 Apr 03.
Article in English | MEDLINE | ID: mdl-18199497

ABSTRACT

Long-term adverse outcomes in Chagas' disease are related to functional, electrical and morphological abnormalities observed in the heart of infected subjects at disease presentation. Both development of acute atrial fibrillation during the time course of the disease and orally transmitted trypanosome infection are further harbingers of poor prognosis. Chagas' disease is a challenging condition in the 21st century, and health care providers and governments are urged to implement joint actions to reduce the impact of the disease by developing preventive actions.


Subject(s)
Chagas Disease/mortality , Chagas Disease/transmission , Atrial Fibrillation/etiology , Atrial Fibrillation/mortality , Chagas Disease/complications , Humans , Prognosis
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