RESUMO
Attractive toxic sugar baits (ATSBs) can be an effective vector control tool, especially in areas where aerial or aquatic applications of pesticides are undesirable or impractical. In general, there is a need to develop novel or alternative insecticides for vector control, and there is a demand from consumers for more 'natural' pest control products. Sodium ascorbate (SA) is a naturally occurring antioxidant compound, found in fruits and vegetables, and is available commercially in the United States as a food additive and supplement. In this study, we continuously exposed groups of adult Aedes aegypti (L.), Anopheles stephensi Liston (Diptera: Culicidae), Phlebotomus papatasi Scopoli, and Lutzomyia longipalpis (Lutz & Neiva; Diptera: Psychodidae) to ATSBs containing SA in concentrations of 6, 8, 10, and 20%, and tracked their mortality over 10 d. We also exposed insects to a 20% SA-ATSB on a single day to determine the effect of a single exposure to the bait on mortality. Concentrations of ≥8% SA significantly reduced survival of both mosquito species over 10 d compared with sugar-fed controls. Sand fly mortality was inconsistent. A single exposure to 20% SA significantly reduced the survival of An. stephensi. Mosquitoes exposed to SA exhibited elevated catalase levels and cell death. The use of SA in ATSBs may be most effective in areas where sugar sources are scarce, and where mosquito species frequently sugar-feed. SA sugar baits may be a particularly attractive option for the general public looking to control mosquito populations using 'natural' alternatives to synthetic insecticides.
Assuntos
Ácido Ascórbico , Culicidae , Controle de Insetos , Inseticidas , Psychodidae , Açúcares , Animais , Relação Dose-Resposta a Droga , Feminino , Masculino , Controle de MosquitosRESUMO
Scrub typhus is caused by Orientia tsutsugamushi, an obligated intracellular bacterium that affects over one million people per year. Several mouse models have been used to study its pathogenesis, disease immunology, and for testing vaccine candidates. However, due to the intrinsic differences between the immune systems in mouse and human, these mouse models could not faithfully mimic the pathology and immunological responses developed by human patients, limiting their value in both basic and translational studies. In this study, we have tested for the first time, a new humanized mouse model through footpad inoculation of O. tsutsugamushi in DRAGA (HLA-A2.HLA-DR4.Rag1KO.IL2RγcKO.NOD) mice with their human immune system reconstituted by infusion of HLA-matched human hematopoietic stem cells from umbilical cord blood. Upon infection, Orientia disseminated into various organs of DRAGA mice resulted in lethality in a dose-dependent manner, while all C3H/HeJ mice infected by the same route survived. Tissue-specific lesions associated with inflammation and/or necroses were observed in multiple organs of infected DRAGA mice. Consistent with the intracellular nature of Orientia, strong Th1, but subdued Th2 responses were elicited as reflected by the human cytokine profiles in sera from infected mice. Interestingly, the percentage of both activated and regulatory (CD4+FOXP3+) human T cells were elevated in spleen tissues of infected mice. After immunization with irradiated whole cell Orientia, humanized DRAGA mice showed a significant activation of human T cells as evidenced by increased number of human CD4+ and CD8+ T cells. Specific human IgM and IgG antibodies were developed after repetitive immunization. The humanized DRAGA mouse model represents a new pre-clinical model for studying Orientia-human interactions and also for testing vaccines and novel therapeutics for scrub typhus.
Assuntos
Modelos Animais de Doenças , Orientia tsutsugamushi , Tifo por Ácaros/imunologia , Animais , Linfócitos T CD8-Positivos/imunologia , Citocinas/sangue , Antígeno HLA-A2/genética , Antígenos HLA-DR/genética , Humanos , Imunização , Imunoglobulina G/sangue , Imunoglobulina M/sangue , Inflamação , Subunidade gama Comum de Receptores de Interleucina/genética , Camundongos , Camundongos Endogâmicos C3H , Camundongos Endogâmicos NOD , Camundongos Transgênicos , Baço/imunologia , Células Th1/imunologia , Células Th2/imunologiaRESUMO
Chlamydial infections in crocodiles have been described in several countries and in several different species. These are typically associated with severe pharyngitis and conjunctivitis, with death occurring secondary to compromise of the upper respiratory tract due to obstruction of the trachea. A population of ranched Siamese crocodiles in central Thailand experienced an epizootic of sudden death in juvenile animals. The affected animals had fulminant systemic disease primarily involving the liver and spleen but also affecting the kidneys, heart, and the whole of the respiratory tract. Chlamydia sp. were noted in liver and spleen during histopathological examination and confirmed with transmission electron microscopy and polymerase chain reaction (PCR). The sequence of the PCR product suggested a novel Chlamydia sp. of Siamese crocodiles. Crocodile farming represents an important economy in several parts of the world. Epizootics, such as the one described in this manuscript in association with Chlamydia sp., can have devastating impact on the industry and represent a potential zoonosis of significant public health concern. This is the first report of Chlamydia sp. and Aeromonas sobria causing systemic disease in crocodiles as well as the first histopathological and ultrastructural description of Chlamydia infection in Siamese crocodiles.
Assuntos
Aeromonas , Jacarés e Crocodilos/microbiologia , Infecções por Chlamydia/veterinária , Chlamydia , Infecções por Bactérias Gram-Negativas/veterinária , Aeromonas/genética , Animais , Chlamydia/genética , Infecções por Chlamydia/complicações , Infecções por Chlamydia/microbiologia , Infecções por Chlamydia/patologia , Coinfecção/microbiologia , Coinfecção/veterinária , Infecções por Bactérias Gram-Negativas/complicações , Infecções por Bactérias Gram-Negativas/microbiologia , Infecções por Bactérias Gram-Negativas/patologia , Fígado/microbiologia , Fígado/patologia , Fígado/ultraestrutura , Microscopia Eletrônica de Transmissão/veterinária , Filogenia , Reação em Cadeia da Polimerase/veterinária , Baço/microbiologia , Baço/patologia , TailândiaRESUMO
We exposed college students to suggestive materials in order to lead them to believe that, as children, they had a negative experience at Disneyland involving the Pluto character. A sizable minority of subjects developed a false belief or memory that Pluto had uncomfortably licked their ear. Suggestions about a positive experience with Pluto led to even greater acceptance of a lovable ear-licking episode. False beliefs and memories had repercussions; those seduced by the bad suggestions were not willing to pay as much for a Pluto souvenir. These findings are among the first to demonstrate that false beliefs can have repercussions for people, meaning that they can influence their later thoughts, beliefs, and behaviors.
Assuntos
Comportamento Agonístico , Comportamento do Consumidor , Tomada de Decisões , Repressão Psicológica , Adulto , California , Feminino , Humanos , MasculinoRESUMO
Limited information is available about the prevalence and phylogenetic classification of fungal organisms in the gastrointestinal tract of dogs. Also, the impact of fungal organisms on gastrointestinal health and disease is not well understood. The aim of this study was to evaluate the prevalence of fungal DNA in the small intestine of healthy dogs and dogs with chronic enteropathies. Small intestinal content was analyzed from 64 healthy and 71 diseased dogs from five different geographic locations in Europe and the USA. Fungal DNA was amplified with panfungal primers targeting the internal transcriber spacer (ITS) region. PCR amplicons were subjected to phylogenetic analysis. Fungal DNA was detected in 60.9% of healthy dogs and in 76.1% of dogs with chronic enteropathies. This prevalence was not significantly different between the two groups (p=0.065). Fungal DNA was significantly more prevalent in mucosal brush samples (82.8%) than in luminal samples (42.9%; p=0.002). Sequencing results revealed a total of 51 different phylotypes. All sequences belonged to two phyla and were classified as either Ascomycota (32 phylotypes) or Basidiomycota (19 phylotypes). Three major classes were identified: Saccharomycetes, Dothideomycetes, and Hymenomycetes. The most commonly observed sequences were classified as Pichia spp., Cryptococcus spp., Candida spp., and Trichosporon spp. Species believed to be clinically more important were more commonly observed in diseased dogs. These results indicate a high prevalence and diversity of fungal DNA in the small intestine of both healthy dogs and dogs with chronic enteropathies. The canine gastrointestinal tract of diseased dogs may harbor opportunistic fungal pathogens.
Assuntos
DNA Fúngico/classificação , DNA Fúngico/isolamento & purificação , Doenças do Cão/microbiologia , Enterite/veterinária , Intestino Delgado/microbiologia , Animais , Doença Crônica , Cães , Enterite/microbiologia , Reação em Cadeia da Polimerase/veterinária , RNA Ribossômico 16S/classificação , RNA Ribossômico 16S/genética , Sensibilidade e EspecificidadeRESUMO
In past research, we planted false memories for food related childhood events using a simple false feedback procedure. Some critics have worried that our findings may be due to demand characteristics. In the present studies, we developed a novel procedure designed to reduce the influence of demand characteristics by providing an alternate magnet for subjects' natural suspicions. We used two separate levels of deception. In addition to giving subjects a typical untrue rationale for the study (i.e., normal deceptive cover story), we built in strong indicators (the "Red Herring") that the study actually had another purpose. Later, we told subjects that we had deceived them, and asked what they believed the "real purpose" of the study was. We also interviewed a subset of subjects in depth in order to analyze their subjective experiences of the procedure and any relevant demand. Our Red Herring successfully tricked subjects, and left little worry that our false memory results were due to demand. This "double cross" technique may have widespread uses in psychological research that hopes to conceal its real hypotheses from experimental subjects.
Assuntos
Atenção , Cultura , Enganação , Repressão Psicológica , Sugestão , Criança , Retroalimentação Psicológica , Comportamento Alimentar , Transtornos da Alimentação e da Ingestão de Alimentos/psicologia , Feminino , Humanos , Masculino , Rememoração Mental , Obesidade/psicologia , Projetos de Pesquisa , Estudantes/psicologia , Adulto JovemRESUMO
In two experiments, involving 231 subjects, we planted the suggestion that subjects loved to eat asparagus as children. Relative to controls, subjects receiving the suggestion became more confident that they had loved asparagus the first time they tried it. These new (false) beliefs had consequences for those who formed them, including increased general liking of asparagus, greater desire to eat asparagus in a restaurant setting, and a willingness to pay more for asparagus in the grocery store. Ratings of photographs made after the suggestion reveal that the altered nutritional choices may relate to the fact that the sight of asparagus simply looks more appetizing and appealing. These results demonstrate that adults can be led to believe that they had a positive food-related experience as children, and that these false beliefs can have healthy consequences.
Assuntos
Comportamento Alimentar/psicologia , Comportamentos Relacionados com a Saúde , Memória , Asparagus , Atitude Frente a Saúde , Retroalimentação Psicológica , Feminino , Alimentos , Humanos , Masculino , Satisfação Pessoal , Comunicação Persuasiva , Adulto JovemRESUMO
This experiment tested the ability of undergraduate mock jurors (N=295) to draw appropriate conclusions from statistical data on the diagnostic value of forensic evidence. Jurors read a summary of a homicide trial in which the key evidence was a bullet lead "match" that was either highly diagnostic, non-diagnostic, or of unknown diagnostic value. There was also a control condition in which the forensic "match" was not presented. The results indicate that jurors as a group used the statistics appropriately to distinguish diagnostic from non-diagnostic forensic evidence, giving considerable weight to the former and little or no weight to the latter. However, this effect was attributable to responses of a subset of jurors who expressed confidence in their ability to use statistical data. Jurors who lacked confidence in their statistical ability failed to distinguish highly diagnostic from non-diagnostic forensic evidence; they gave no weight to the forensic evidence regardless of its diagnostic value. Confident jurors also gave more weight to evidence of unknown diagnostic value. Theoretical and legal implications are discussed.
Assuntos
Balística Forense/estatística & dados numéricos , Julgamento , Chumbo , Metalurgia , Feminino , Humanos , Masculino , Inquéritos e Questionários , Estados UnidosRESUMO
Can judging an individual as being morally responsible for a negative act affect memory for details of the act? We presented participants with a story describing an individual (Frank) who committed a crime (he walked out on a restaurant bill). Some participants were told that the negative act was not intentional and that Frank was essentially a good person. Others were told that the negative act was intentional and that Frank actually enjoyed it. Control participants were given no extra information. All the participants then judged Frank's moral responsibility for walking out on the bill. When asked a week later to recall information about the event, the participants who had received negative information about Frank remembered that Frank had walked out on a larger restaurant bill than he actually had. Moreover, the degree of memory distortion was predicted by the degree of moral blame that had been attributed to Frank.
Assuntos
Culpa , Julgamento , Acontecimentos que Mudam a Vida , Memória , Princípios Morais , HumanosRESUMO
When given suggestive information, some people can be led to believe that they had experiences that they did not actually have. For example, they may come to believe falsely that they got sick eating particular foods as children, and as a result of that belief they may avoid the foods. But how do we know that someone has developed a false belief or memory in this research? The criteria we choose when classifying whether someone has fallen for the suggestion are somewhat arbitrary. We reanalyze our prior data, using different criteria for deciding that a person fell for the suggestion (called a "believer") or did not (called a "non-believer"). Changing criteria obviously affects the percentage of people who are called susceptible and could conceivably affect the conclusions reached about that group. Comparisons between false memories and true memories could differ, too, depending on how memories are defined.
Assuntos
Cultura , Enganação , Memória , Humanos , SugestãoRESUMO
We suggested to 228 subjects in two experiments that, as children, they had had negative experiences with a fattening food. An additional 107 subjects received no such suggestion and served as controls. In Experiment 1, a minority of subjects came to believe that they had felt ill after eating strawberry ice cream as children, and these subjects were more likely to indicate not wanting to eat strawberry ice cream now. In contrast, we were unable to obtain these effects when the critical item was a more commonly eaten treat (chocolate chip cookie). In Experiment 2, we replicated and extended the strawberry ice cream results. Two different ways of processing the false suggestion succeeded in planting the false belief and producing avoidance of the food. These findings show that it is possible to convince people that, as children, they experienced a negative event involving a fattening food and that this false belief results in avoidance of that food in adulthood. More broadly, these results indicate that we can, through suggestion, manipulate nutritional selection and possibly even improve health.