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1.
J Gerontol B Psychol Sci Soc Sci ; 78(11): 1834-1842, 2023 11 14.
Artigo em Inglês | MEDLINE | ID: mdl-37480567

RESUMO

OBJECTIVES: Frailty is not an end state of aging, but rather represents physiological vulnerability across multiple systems that unfolds across adulthood. However, examinations of frailty at the midlife transition, and how frailty may impact other age-sensitive traits, such as processing speed (PS), remain scarce. Our research aims were to examine frailty and frailty-speed associations before midlife, a ripe developmental period for healthy aging interventions. METHODS: Using data from the Colorado Adoption/Twin Study of Lifespan behavioral development and cognitive aging (N = 1,215; Mage = 33.23 years; standard deviation = 4.98), we constructed 25-item (FI25) and 30-item (FI30) frailty indices. PS was measured using the Colorado Perceptual Speed task and WAIS-III Digit Symbol (DS) subtest. Multilevel models accounted for clustering among siblings and adjusted for sex, race, ethnicity, adoption status, educational attainment, and age. RESULTS: Reliability of FI measures was apparent from strong intraclass correlations (ICCs) among identical twin siblings, although ICC patterns across all siblings suggested that FI variability may include nonadditive genetic contributions. Higher FI was associated with poorer PS performance but was significant for DS only (BFI25 = -1.17, p = .001, d = -0.12; BFI30 = -1.21, p = .001, d = -0.12). Furthermore, the negative frailty-DS association was moderated by age (BFI25×age = -0.14, p = .042; BFI30×age=-0.19, p = .008) where increasingly worse performance with higher frailty emerged at older ages. DISCUSSION: Frailty is evident before midlife and associated with poorer PS, an association that magnifies with age. These findings help elucidate the interrelationship between indicators of frailty and cognitive performance for adults approaching midlife, an understudied period within life-span development.


Assuntos
Envelhecimento Cognitivo , Fragilidade , Humanos , Adulto , Velocidade de Processamento , Reprodutibilidade dos Testes , Envelhecimento/psicologia
2.
Neotrop Entomol ; 52(2): 251-262, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-36478342

RESUMO

The suborder Heteroptera (Hemiptera) includes zoophagous and zoophytophagous species which conform diverse natural enemies' systems with potential to control several horticultural pests. In this study, we report the assemblage structure of heteropteran bugs species inhabiting open-field and greenhouse organic tomato crops and one common adjacent non-crop solanaceous plant, Solanum sisymbriifolium, in North Buenos Aires province, Argentina, aimed to select promissory biocontrol species. Biweekly direct inspection of selected plants was carried out during a 3-year period (2017-2019) to collect hemipteran nymphs and adults. As a result, nine species and morphospecies belonging to Berytidae (zoophytophagous), Lygaeidae (phytophagous), and Miridae (phytophagous and zoophytophagous) were found, with ≥ 75% of species belonging to the latter family. The zoophytophagous mirid Tupiocoris cucurbitaceus (Spinola) was the most frequent and dominant species in all sites studied. Among the phytophagous species, Nysius simulans Stål was mostly present in greenhouse crops. The community found in greenhouse tomato crops was more diverse than that registered in open-field crops. The characterization of the heteropteran complex in organic tomato farms provides basic knowledge necessary to design pest control strategies in the region studied.


Assuntos
Heterópteros , Mariposas , Solanum lycopersicum , Animais , Fazendas , Controle Biológico de Vetores
3.
J Econ Entomol ; 111(2): 528-532, 2018 04 02.
Artigo em Inglês | MEDLINE | ID: mdl-29294007

RESUMO

Pseudapanteles dignus (Muesebeck; Hymenoptera: Braconidae) is an American endoparasitoid that attacks the South American tomato leafminer Tuta absoluta (Meyrick; Lepidoptera: Gelechiidae). The interaction between P. dignus and T. absoluta in tomato (Solanum lycopersicum L.; Solanales: Solanaceae) crops has demonstrated that this enemy exhibits some desirable ecological traits as an effective biological control agent of this pest. With the aim of extending the use of P. dignus to other solanaceous crops, laboratory experiments were carried out to assess some life history traits and the parasitism efficiency when parasitizing T. absoluta larvae fed on eggplant (Solanum melongena L.; Solanales: Solanaceae). Rearings and experiments were conducted at 25 ± 2°C, ≈70% RH, and 14:10 (L:D) h photoperiod, and T. absoluta was fed with eggplant. P. dignus developmental times of immature stages were lower (~ 5 d) on S. melongena than on S. lycopersicum. The female did not exhibit a pre-reproductive period, and its oviposition period lasted longer (~ 4 d) than that determined in tomato plants. Adult longevity was ca. 24 d for both sexes. Females produced ca. 61 cocoons during their lives and the maximum daily percentage of parasitism was 50% at the first day of adult emergence. Functional response of P. dignus on eggplant was density-independent of the host density offered, as in tomato plant, and the instantaneous attack rate (a') was 0.24 attacked larvae/ available larvae, in 24 h. Our results indicate that although there are differences, P. dignus would have a similar performance in eggplant and tomato in terms of its efficacy in the control of T. absoluta.


Assuntos
Interações Hospedeiro-Parasita , Mariposas/parasitologia , Controle Biológico de Vetores , Solanum melongena , Vespas/crescimento & desenvolvimento , Animais , Feminino , Longevidade , Masculino
4.
Insect Sci ; 24(5): 809-817, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-27226404

RESUMO

Dicyphus maroccanus Wagner and Nesidiocoris tenuis Reuter (Hemiptera: Miridae) are 2 biological control agents in tomatoes. Through the crop seasons, a natural shift in the occurrence of both mirids in favor of N. tenuis has been observed at the end of the cropping cycle in eastern Spain. To better optimize their conservation, the reasons for the observed change, such as intraguild interactions (IGP) or the influence of environmental conditions, are worth elucidating. To do this, we first studied the IGP of adult females on heterospecific nymphs in the laboratory. We next studied exploitative competition between adults and nymphs of each species when feeding on Ephestia kueniella Zeller (Lepidoptera: Pyralidae) eggs in the laboratory. Finally, to analyze the competitive displacement between both mirids, we conducted a semifield experiment in which both predators were released together. All experiments were conducted at 2 temperature regimes (20 and 25°C). Adult-to-nymph intraguild interactions occurred only at 25 ºC at very low levels, showing that N. tenuis attacked and consumed a greater proportion of heterospecific nymphs. Nesidiocoris tenuis was a better competitor than D. maroccanus when feeding on the shared prey in the presence of its heterospecific nymph at 25 ºC. In semifield conditions, N. tenuis showed a competitive advantage over D. maroccanus at both temperatures. We conclude that there is not direct interference between both species, however, N. tenuis has a greater ability to outcompete, since it is best adapted to higher temperatures and it is able to remove food sources for D. maroccanus.


Assuntos
Hemípteros , Mariposas , Controle Biológico de Vetores , Comportamento Predatório , Solanum lycopersicum , Animais , Feminino , Ninfa
5.
PLoS One ; 11(10): e0163196, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27732609

RESUMO

Endoparasitoids can be killed by host encapsulation, a cellular-mediated host immunological response against parasitism that involves hemocytes aggregation. As a counteracting strategy, many parasitoids can evade this host response through self-superparasitism. The objectives of this study were: 1) to describe the parasitoid Pseudapanteles dignus (Hymenoptera: Braconidae) early immature stages (egg and larva) encapsulation by the host Tuta absoluta (Lepidoptera: Gelechiidae), and 2) to determine the occurrence of self-superparasitism and the rate of escaping to encapsulation of this parasitoid. Knowledge of host-parasitoid immunological interaction is crucial when evaluating the potential of an endoparasitoid as a biological control candidate. Parasitoid-exposed T. absoluta larvae were dissected in vivo under light stereoscope microscope at 24-h intervals, for five days after exposition to detect encapsulation. The preimaginal stages of P. dignus and numbers of healthy and encapsulated immature parasitoids per host were recorded. Samples of parasitoid eggs and larvae were processed for SEM visualization of encapsulation. Necropsies evidenced that only the early first larval instar of P. dignus (up to 96 h-old) was partially or completely encapsulated. A non-melanized capsule, formed by layers of granulocyte-type hemocytes enveloping around the parasitoid body, was recorded. Approximately 50% of the parasitized T. absoluta larvae had significantly only one P. dignus egg, meanwhile supernumerary parasitization yielded up to seven immature parasitoids per host. The proportion of single-early first larval instar of P. dignus reached ≈ 0.5 and decreased significantly as the number of parasitoid individuals per host increased. P. dignus encapsulation and its ability to overcome with the host immune defense through self-superparasitism indicate that T. absoluta is a semi-permissive host for this parasitoid.


Assuntos
Himenópteros/fisiologia , Lepidópteros/parasitologia , Animais , Hemócitos/parasitologia , Interações Hospedeiro-Parasita/imunologia , Himenópteros/crescimento & desenvolvimento , Larva , Estágios do Ciclo de Vida , Microscopia Eletrônica de Varredura , Controle Biológico de Vetores
6.
J Econ Entomol ; 108(4): 1553-9, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-26470295

RESUMO

The tomato moth, Tuta absoluta (Meyrick) (Lepidoptera: Gelechiidae), is a key pest of tomato, Lycopersicon esculentum L., crops in Central and South America. At present it is dispersing rapidly in Africa and Eurasian continents as an invasive pest, threatening worldwide tomato production. Pseudapanteles dignus (Muesebeck) (Hymenoptera: Braconidae) is an American endoparasitoid reported as the main natural enemy of T. absoluta in commercial tomato. To gain knowledge of the potential role of P. dignus in the biological control of this pest, we determined its population parameters in laboratory and the parasitoid's impact on T. absoluta in the field. In laboratory, lifetime fecundity was 193 eggs per female, and longevity was 24 and 26 d for female and male, respectively. The finite rate of increase (λ) was 1.15 per female per day and the intrinsic rate of natural increase (r(m)) was 0.14. The net reproductive rate (R(0)) was found to be 51.2, and generation time (T) 28.8 d. The time for doubling the population (DT) was 5 d. Furthermore, field parasitism of T. absoluta varied between 33 and 64% in the different years studied. Population parameters estimated in this study can be considered baseline information for a mass-rearing protocol of this parasitoid. Moreover, growth rates of P. dignus, particularly r(m), and its impact on field populations of T. absoluta indicated that this parasitoid is a valuable candidate for biological control of this pest.


Assuntos
Interações Hospedeiro-Parasita , Mariposas/parasitologia , Controle Biológico de Vetores , Vespas/fisiologia , Animais , Argentina , Feminino , Larva/crescimento & desenvolvimento , Larva/parasitologia , Solanum lycopersicum/crescimento & desenvolvimento , Masculino , Mariposas/crescimento & desenvolvimento , Dinâmica Populacional
7.
J Insect Sci ; 12: 1-14, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-23464576

RESUMO

The tomato moth, Tuta absoluta (Lepidoptera: Gelechiidae), is a major pest in South America and is at present an important invasive species in the Mediterranean Basin. The larval stadium mines leaves, stems, and fruits, and chemical control is the most used control method in both its original range and the invaded distribution regions. Since current T. absoluta control strategies seem limited, biological control is a prominent tool to be applied abroad. The naturally occurring larval ectoparasitoid in Argentina and Chile Dineulophus phtorimaeae (Hymenoptera: Eulophidae) has been reported to have potential biocontrol efficiency. In this study, the ovigeny strategy of D. phtorimaeae was analyzed throughout the adult female lifetime, and the functional response of females offered a range of 2-15 T. absoluta larvae was measured over a 48-hour period. Mean D. phtorimaeae egg load was 4.15 eggs, and egg production resulted in extremely synovigenic behavior. Meanwhile, a decreasing number of eggs, due to resorption, was found. Proportions of attacked (host-fed and/or parasitized) and only host-fed hosts by the ectoparasitoid were density independent for the tested host range, exhibiting a type I functional response to T. absoluta, with an attack rate of 0.20 host larvae. Meanings of this reproductive strategy in evolutionary time as well as the consequences for augmentative biological control programs are discussed.


Assuntos
Himenópteros/fisiologia , Mariposas/parasitologia , Animais , Feminino , Interações Hospedeiro-Parasita , Larva/crescimento & desenvolvimento , Larva/parasitologia , Solanum lycopersicum/crescimento & desenvolvimento , Mariposas/crescimento & desenvolvimento , Oviposição , Controle Biológico de Vetores
8.
Environ Entomol ; 38(2): 365-74, 2009 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-19389284

RESUMO

We examined the interaction between the tomato leafminer, Tuta absoluta (Meyrick) (Lepidoptera: Gelechiidae), a key pest of tomato crops in South America, and its main solitary larval parasitoid, Pseudapanteles dignus (Muesebeck) (Hymenoptera: Braconidae). The pattern of parasitism of T. absoluta by the parasitoid was studied at three scales on tomato crops: plant, leaf, and leaflet. Host density, spatial distributions of both host and parasitoid, percentages of parasitism, variation in the probability and risk of parasitism in relation to host density, and the spatial density dependence were assessed in a horticultural region in Argentina. The spatial distribution of T. absoluta was clumped at all sites and scales, whereas that of P. dignus was much more variable, fitting to negative, positive binomial distributions and to Poisson series. Percentages of parasitism were as follows: site 1, 17.06%; site 2, 27.53%; site 3, 26.47%; site 4, 45.95%. Parasitoid aggregation in relation to host density was found at leaf and leaflet scales. However, the proportion of parasitized hosts was independent of host density. The variability of parasitism rates exhibited at the three spatial scales seems to result in partial refuges for the host, which might contribute to the persistence of the interaction between host and parasitoid. We discuss our field observations in relation to ecological theory and its potential application to the biological control of T. absoluta on tomato.


Assuntos
Mariposas/parasitologia , Vespas/fisiologia , Animais , Argentina , Feminino , Interações Hospedeiro-Parasita , Controle Biológico de Vetores , Densidade Demográfica
9.
Environ Entomol ; 36(4): 887-93, 2007 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-17716480

RESUMO

Laboratory studies were conducted to measure selected life history traits and the functional response of the parasitoid Pseudapanteles dignus (Muesebeck), a major enemy of Tuta absoluta (Meyrick) in tomato crops in South America. Newly mated P. dignus females were individually exposed to 10 host larvae in mines for 24 h. We determined developmental time from egg to pupal formation and pupal stage duration, female adult life span, fecundity, reproductive period, daily parasitism rate, and sex ratio of offspring. For the functional response experiment, treatments consisted of six host densities: 3, 5, 7, 10, 15, 20, or 30 larvae. The number and proportion of parasitized hosts were calculated for each density. The shape of the functional response curve was analyzed by logistic regression. P. dignus females attacked hosts daily, exhibiting modest lifetime fecundity (approximately 32 parasitized hosts per female) and a female-biased offspring sex ratio. Female adult life span was 36 d. P. dignus showed a type I functional response within the range of host densities tested. We observed that females detect and parasitize the host within a wide range of densities, including low densities. The functional response curve reached an asymptote at a mean density of six hosts per day and seemed not to be egg-limited. Percent parasitism was approximately 30%. The ecological implications of the results in relation to the potential of P. dignus for the biological control of T. absoluta in tomato are discussed.


Assuntos
Himenópteros/fisiologia , Mariposas/parasitologia , Animais , Feminino , Interações Hospedeiro-Parasita , Larva/parasitologia , Estágios do Ciclo de Vida , Masculino , Controle Biológico de Vetores
10.
J Infect Dis ; 189(8): 1515-23, 2004 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-15073690

RESUMO

Blood samples from Peromyscus leucopus mice captured at an enzootic site in Connecticut were examined for antibodies to and DNA of Borrelia burgdorferi, to characterize the dynamics of infection in this reservoir population. From trappings conducted over the course of 2 transmission seasons, 598 (75%) of 801 serum samples from 514 mice were found to be positive by enzyme immunoassay. Seropositivity correlated with date of capture and mouse age, was similar among locations within the site, increased from 57% to 93% over the course of the transmission season, and was associated with antibodies to outer surface protein (Osp) C, but not to OspA. Longitudinal samples from 184 mice revealed an incidence of 0.2 cases/mouse/week. Nineteen (10%) of 187 samples were found by polymerase chain reaction to be positive for B. burgdorferi, and, of those, 14 (74%) were found to be seropositive. Nearly the entire population of P. leucopus mice became infected with B. burgdorferi by late August, coinciding with the peak activity period of host-seeking larvae uninfected with the spirochete Ixodes scapularis, thereby perpetuating the agent through succeeding generations of ticks.


Assuntos
Antígenos de Bactérias , Borrelia burgdorferi/isolamento & purificação , Doenças Endêmicas , Doença de Lyme/veterinária , Peromyscus , Doenças dos Roedores/microbiologia , Animais , Anticorpos Antibacterianos/sangue , Proteínas da Membrana Bacteriana Externa/imunologia , Western Blotting/veterinária , Borrelia burgdorferi/genética , Borrelia burgdorferi/imunologia , Connecticut/epidemiologia , DNA Bacteriano/química , DNA Bacteriano/genética , Reservatórios de Doenças/veterinária , Feminino , Técnicas Imunoenzimáticas/veterinária , Incidência , Ixodes/microbiologia , Estudos Longitudinais , Doença de Lyme/epidemiologia , Doença de Lyme/microbiologia , Reação em Cadeia da Polimerase/veterinária , Doenças dos Roedores/epidemiologia , Estações do Ano , Estudos Soroepidemiológicos
11.
Rev. ADM ; 60(1): 5-13, ene.-feb. 2003. ilus
Artigo em Espanhol | LILACS | ID: lil-350564

RESUMO

El propósito del presente estudio fue la detección de la serotonina en la sutura media palatina durante el proceso inflamatorio causado por la expansión rápida maxilar (ERM). La serotonina juega un papel importante como mediador químico en el proceso inflamatorio agudo, el cual se relaciona especialmente con la permeabilidad vascular y la producción de dolor durante la aplicación de fuerzas ortopédicas que se generan como una respuesta inflamatoria en la sutura media palatina. Al realizarse la ERM se produce la seperación física del maxilar por medio de la aplicación de técnicas que pueden producir una respuesta ortopédica. Estas técnicas se usan en pacientes que necesitan un aumento en el plano transversal del maxilar, principalmente durante la dentición primaria, mixta y en algunas ocasiones en la dentición permanente, de acuerdo con la edad del paciente, creando modificaciones en la sutura media palatina y en otras estructuras craneofaciales que se encuentran relacionadas con el maxilar. Veinticuatro conejos machos de la cepa Nueva Zelanda fueron incluidos en el presente estudio, a los animales se les colocó un expansor modificado para llevar a cabo la ERM. El maxilar se disecó a los 7, 14 y 21 días después que el aparato se inseró en la boca del conejo. Se obtuvieron muestras de tejido del maxilar, se realizó la técnica de inmunohistoquímica indirecta, utilizando un anticuerpo monoclonal de ratón contra la serotonina. La serotonina no se detectó en ninguno de los grupos experimentales


Assuntos
Animais , Coelhos , Serotonina , Técnica de Expansão Palatina/efeitos adversos , Anticorpos Monoclonais , Imuno-Histoquímica/métodos , Maxila , Mediadores da Inflamação/fisiologia , Coelhos
12.
Microbiology (Reading) ; 143 ( Pt 10): 3201-3207, 1997 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-9353922

RESUMO

Antibodies raised against four hybrid Salmonella flagellins carrying amino acid sequences derived from the fimbrial subunit of the colonization factor I antigen (CFA/I) of enterotoxigenic Escherichia coli (ETEC), i.e. hybrid flagellins Fla I (aa 1-15), Fla II (aa 11-25), Fla III (aa 32-45) and Fla IV (aa 88-102), were not able to inhibit the in vitro binding of CFA/I-expressing ETEC bacteria to enterocyte-like Caco-2 cells. However, one of the hybrid flagellins (Fla II) was recognized by a previously described anti-CFA/I subunit mAb (S-CFA/I 17:8) which was able to block adhesion of CFA/I-expressing bacteria to Caco-2 cells and to bind to the amino acid sequences 15IDLLQ19 of the CFA/I fimbrial subunit. Pepscan analysis of antibodies raised against the hybrid flagellins Fla II and Fla IV showed that they were specific for the sequences 14VIDLL18 and 96FEAAAL101, respectively, of the CFA/I fimbrial subunit. Thus, the discrepancy in the abilities of the anti-Fla II serum and the mAb S-CFA/I 17:8 to block binding might be ascribed to their slightly different fine specificity for epitopes.


Assuntos
Antígenos de Bactérias/genética , Proteínas de Bactérias/genética , Proteínas de Bactérias/imunologia , Proteínas de Fímbrias , Sequência de Aminoácidos , Animais , Anticorpos Monoclonais , Especificidade de Anticorpos , Aderência Bacteriana , Células CACO-2 , Epitopos/genética , Escherichia coli/genética , Escherichia coli/imunologia , Escherichia coli/patogenicidade , Flagelina/genética , Flagelina/imunologia , Humanos , Camundongos , Microscopia Imunoeletrônica , Dados de Sequência Molecular , Oligopeptídeos/genética , Oligopeptídeos/imunologia , Proteínas Recombinantes de Fusão/genética , Proteínas Recombinantes de Fusão/imunologia , Salmonella/genética , Salmonella/imunologia , Salmonella/ultraestrutura
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