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1.
J Chem Ecol ; 44(6): 556-564, 2018 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-29770906

RESUMO

Beetles in the genus Sphenophorus Schönherr, or billbugs, potentially utilize both volatile and non-volatile behavior-modifying chemical signals. These insects are widely distributed across North America, often occurring in multi-species assemblages in grasses. However, details about their host- and mate-finding behavior are poorly understood. This study tested the hypothesis that volatile organic compounds from host-plants and conspecifics direct the dispersal behavior of hunting billbug S. venatus Say. Further, we characterized the cuticular hydrocarbon profiles of two widespread pest species, S. venatus and bluegrass billbug S. parvulus Gyllenhaal, to assess the potential role of contact pheromones in mate-recognition. In Y-tube olfactometer bioassays, S. venatus males were attracted to a combination of conspecifics and Cynodon dactylon host-plant material, as well as C. dactylon plant material alone. S. venatus females were attracted to a combination of male conspecifics and host-plants but were also attracted to male conspecifics alone. Field evaluation of a putative male-produced aggregation pheromone, 2-methyl-4-octanol, identified from two congeners, S. levis Vaurie and S. incurrens Gyllenhaal, did not support the hypothesis that S. venatus and S. parvulus were also attracted to this compound. Gas chromatography-mass spectrometry analysis of S. venatus and S. parvulus whole-body cuticular extracts indicated a series of hydrocarbons with qualitative and quantitative interspecific variation in addition to intraspecific quantitative variation between males and females. This study provides the first evidence that S. venatus orients toward host- and insect-derived volatile organic compounds and substantiates the presence of species-specific cuticular hydrocarbons that could serve as contact pheromones for sympatric Sphenophorus species.


Assuntos
Besouros/fisiologia , Plantas/química , Comportamento Sexual Animal/fisiologia , Compostos Orgânicos Voláteis/análise , Animais , Fracionamento Químico , Feminino , Cromatografia Gasosa-Espectrometria de Massas , Hidrocarbonetos/análise , Hidrocarbonetos/isolamento & purificação , Masculino , Extratos Vegetais/química , Plantas/metabolismo , Plantas/parasitologia , Compostos Orgânicos Voláteis/química , Compostos Orgânicos Voláteis/isolamento & purificação
2.
Ecol Evol ; 13(7): e10213, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37435026

RESUMO

Regional populations of geographically widespread species may respond to different environmental factors across the species' range, generating divergent effects of climate change on life-history phenology. Using thousands of citizen science observations extracted from iNaturalist and associated with corresponding temperature, precipitation, elevation, and daylength information, we examined the drivers of adult mating and of nymphal phenology, development, and group size for populations of the large milkweed bug, Oncopeltus fasciatus, in different ecoregions. Research-grade iNaturalist images were correctly identified 98.3% of the time and yielded more than 3000 observations of nymphal groups and 1000 observations of mating adults spanning 18 years. Mating phenology showed distinct regional patterns, ranging from year-round mating in California to temporally restricted mating in the Great Lakes Northeastern Coast ecoregion. Relative temperature increases of 1°C for a given daylength expanded the mating season by more than a week in western ecoregions. While increases in relative temperature delayed mating phenology in all ecoregions, greater winter precipitation advanced mating in the California ecoregion. In the eastern ecoregions, nymphal phenology was delayed by increases in summer rainfall but was advanced by relative temperature increases, whereas in western regions, relative temperature increases delayed nymphal phenology. Furthermore, accumulated growing degree days (AGDD) was a poor predictor of developmental progression, as we found a positive but weak correlation between AGDD and age structure only for the Appalachian Southeast North America and the Great Lakes Northern Coast ecoregions. These complex phenological responses of O. fasciatus are just one example of how populations may be differentially susceptible to a diversity of climatic effects; using data across a species' whole distribution is critical for exposing regional variations, especially for species with large, continental-scale ranges. This study demonstrates the potential of photodocumented biodiversity data to aid in the monitoring of life history, host plant-insect interactions, and climate responsiveness.

3.
J Am Coll Emerg Physicians Open ; 2(5): e12522, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34528023

RESUMO

STUDY OBJECTIVE: Approximately 5% of emergency department patients present with altered mental status (AMS). AMS is diagnostically challenging because of the wide range of causes and is associated with high mortality. We sought to develop a clinical decision rule predicting admission risk among emergency department (ED) patients with AMS. METHODS: Using retrospective chart review of ED encounters for AMS over a 2-month period, we recorded causes of AMS and numerous clinical variables. Encounters were split into those admitted to the hospital ("cases") and those discharged from the ED ("controls"). Using the first month's data, variables correlated with hospital admission were identified and narrowed using univariate and multivariate statistics, including recursive partitioning. These variables were then organized into a clinical decision rule and validated on the second month's data. The decision rule results were also compared to 1-year mortality. RESULTS: We identified 351 encounters for AMS over a 2-month period. Significant contributors to AMS included intoxication and chronic disorder decompensation. ED data predicting hospital admission included vital sign abnormalities, select lab studies, and psychiatric/intoxicant history. The decision rule sorted patients into low, moderate, or high risk of admission (11.1%, 44.3%, and 89.1% admitted, respectively) and was predictive of 1-year mortality (low-risk group 1.8%, high-risk group 34.3%). CONCLUSIONS: We catalogued common causes for AMS among patients presenting to the ED, and our data-driven decision tool triaged these patients for risk of admission with good predictive accuracy. These methods for creating clinical decision rules might be further studied and improved to optimize ED patient care.

4.
Arthropod Plant Interact ; 14(6): 671-684, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33193908

RESUMO

Insect chemical ecology (ICE) evolved as a discipline concerned with plant-insect interactions, and also with a strong focus on intraspecific pheromone-mediated communication. Progress in this field has rendered a more complete picture of how insects exploit chemical information in their surroundings in order to survive and navigate their world successfully. Simultaneously, this progress has prompted new research questions about the evolution of insect chemosensation and related ecological adaptations, molecular mechanisms that mediate commonly observed behaviors, and the consequences of chemically mediated interactions in different ecosystems. Themed meetings, workshops, and summer schools are ideal platforms for discussing scientific advancements as well as identifying gaps and challenges within the discipline. From the 11th to the 22nd of June 2018, the 11th annual PhD course in ICE was held at the Swedish University of Agricultural Sciences (SLU) Alnarp, Sweden. The course was made up of 35 student participants from 22 nationalities (Fig. 1a) as well as 32 lecturers. Lectures and laboratory demonstrations were supported by literature seminars, and four broad research areas were covered: (1) multitrophic interactions and plant defenses, (2) chemical communication focusing on odor sensing, processing, and behavior, (3) disease vectors, and (4) applied aspects of basic ICE research in agriculture. This particular article contains a summary and brief synthesis of these main emergent themes and discussions from the ICE 2018 course. In addition, we also provide suggestions on teaching the next generation of ICE scientists, especially during unprecedented global situations.

5.
J Econ Entomol ; 111(1): 304-313, 2018 02 09.
Artigo em Inglês | MEDLINE | ID: mdl-29309605

RESUMO

Eleven species of billbugs (Coleoptera: Dryophthoridae: Sphenophorus spp. Schönherr) infest managed turfgrass in North America. However, the regional variation in species composition remains unresolved and the seasonal phenology of several species has not been well documented. The latter gap is largely due to the inability to identify the larval stage to species-a confounding problem with several sympatric insect species. We used field trapping (adults) and soil sampling (larvae and pupae) surveys along with a DNA-based life-stage association to characterize the biology of billbugs associated with turfgrass in the Midwestern United States. Pitfall trapping at four locations in Indiana revealed four billbug species: S. venatus Say, S. parvulus Gyllenhaal, S. minimus Hart, and S. inaequalis Say. Sphenophorus venatus was the most abundant species on warm-season turfgrass while S. parvulus was most abundant on cool-season turfgrass. Investigation of S. venatus seasonal biology revealed two overwintered life stages-larva and adult-which resulted in two overlapping cohorts and two larval generations. Degree-day models describing S. venatus activity were more accurate for first-generation adults and larvae than for overwintering life stages. Maximum-likelihood analyses provided the first molecular species identification of billbug larvae and direct evidence that S. venatus larvae are capable of overwintering above 40°N latitude. Findings clarify the utility of molecular markers (CO1, 18S, and ITS2) for describing billbug larval population dynamics and seasonal phenology in regions where several sympatric billbug species occur. These results support the development of sustainable management strategies based on billbug seasonal phenology in different regions of North America.


Assuntos
Besouros/fisiologia , Características de História de Vida , Animais , Biota , Besouros/classificação , Besouros/genética , Besouros/crescimento & desenvolvimento , DNA Espaçador Ribossômico/genética , Complexo IV da Cadeia de Transporte de Elétrons/genética , Indiana , Proteínas de Insetos/genética , Larva/classificação , Larva/genética , Larva/crescimento & desenvolvimento , Larva/fisiologia , Dinâmica Populacional , RNA Ribossômico 18S/genética , Estações do Ano
6.
Brain Behav ; 7(6): e00639, 2017 06.
Artigo em Inglês | MEDLINE | ID: mdl-28638698

RESUMO

OBJECTIVE: Parkinson's disease psychosis (PDP) is a frequent complication of idiopathic Parkinson's disease (iPD) with significant impact on quality of life and association with poorer outcomes. Atypical antipsychotic drugs (APDs) are often used for the treatment of PDP; however, their use is often complicated by adverse drug reactions (ADRs). In this study, we present patients with PDP who were treated with the most commonly used atypical antipsychotic agents and review their respective ADRs. METHODS: A retrospective study was carried out to include a total of 45 patients with iPD who visited a movement disorders clinic between 2006 and 2015. All PDP patients treated with atypical APDs were included in the analysis for their specific ADRs. RESULTS: Forty-five iPD patients (mean age of onset: 62.67 ± 9.86 years) were included, of those 10 patients had psychosis (mean age of onset: 76.80 ± 4.61 years). Of the 45 patients, 22.2% were found to have psychotic symptoms, of whom 70% had hallucinations, 20% had delusions, and 10% illusions. Seventy percent of psychotic symptoms occurred after ten or more years from diagnosis of iPD. PDP patients were treated with quetiapine, olanzapine, and risperidone separately or in combination, all of which were found to have certain ADRs. LIMITATIONS: This study was limited by its retrospective study design and small sample size and with likely selection bias. CONCLUSIONS: The prevalence of PDP is relatively high in older patients with iPD. The uses of the currently available atypical APDs in this patient population are often complicated by ADRs. The selective 5-HT 2A inverse agonist, pimavanserin, could be a better alternative in the treatment of PDP.


Assuntos
Benzodiazepinas , Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos , Doença de Parkinson , Piperidinas , Transtornos Psicóticos/tratamento farmacológico , Qualidade de Vida , Ureia/análogos & derivados , Idoso , Antipsicóticos/administração & dosagem , Antipsicóticos/efeitos adversos , Benzodiazepinas/administração & dosagem , Benzodiazepinas/efeitos adversos , Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos/diagnóstico , Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos/etiologia , Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos/prevenção & controle , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Olanzapina , Avaliação de Processos e Resultados em Cuidados de Saúde , Doença de Parkinson/complicações , Doença de Parkinson/psicologia , Piperidinas/administração & dosagem , Piperidinas/efeitos adversos , Técnicas Psicológicas , Transtornos Psicóticos/diagnóstico , Transtornos Psicóticos/etiologia , Estudos Retrospectivos , Ureia/administração & dosagem , Ureia/efeitos adversos
8.
Cell Transplant ; 25(4): 677-86, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26850319

RESUMO

Huntington's disease (HD) is an autosomal dominant neurodegenerative disorder caused by an abnormal expansion of CAG repeats. Although pathogenesis has been attributed to this polyglutamine expansion, the underlying mechanisms through which the huntingtin protein functions have yet to be elucidated. It has been suggested that postnatal reduction of mutant huntingtin through protein interference or conditional gene knockout could prove to be an effective therapy for patients suffering from HD. For allele-specific targeting, transcription activator-like effectors (TALE) were designed to target single-nucleotide polymorphisms (SNP) in the mutant allele and packaged into a vector backbone containing KRAB to promote transcriptional repression of the disease-associated allele. Additional TALEs were packaged into a vector backbone containing heterodimeric FokI and were designed to be used as nucleases (TALEN) to cause a CAG-collapse in the mutant allele. Human HD fibroblasts were treated with each TALE-SNP or TALEN. Allele-expression was measured using a SNP-genotyping assay and mutant protein aggregation was quantified with Western blots for anti-ubiquitin. The TALE-SNP and TALEN significantly reduced mutant allele expression (p < 0.05) when compared to control transfections while not affecting expression of the nondisease allele. This study demonstrates the potential of allele-specific gene modification using TALE proteins, and provides a foundation for targeted treatment for individuals suffering from Huntington's or other genetically linked diseases.


Assuntos
Alelos , Fibroblastos/metabolismo , Proteína Huntingtina , Doença de Huntington , Polimorfismo de Nucleotídeo Único , Ativação Transcricional , Feminino , Técnicas de Silenciamento de Genes , Humanos , Proteína Huntingtina/biossíntese , Proteína Huntingtina/genética , Doença de Huntington/genética , Doença de Huntington/metabolismo , Masculino
9.
Neurol Clin Pract ; 4(6): 526-527, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-29443149
10.
Dev Neurosci ; 25(6): 436-46, 2003.
Artigo em Inglês | MEDLINE | ID: mdl-14966384

RESUMO

Pericyte loss or migration from its vascular location may be an important step in microvascular remodeling. Decreased pericyte to endothelial ratios are characteristics of newly formed vessels as well as microvessels undergoing regression, and may be due to selective degeneration via necrotic cell death or via programmed cell death. In this study, we have examined glucocorticoid-induced apoptosis in primary rat CNS pericytes. Characterization of apoptosis was determined using five independent criteria: (1) the translocation of receptors for annexin V from the inner to the outer surface of the plasma membrane, (2) the translocation of cytochrome C from the mitochondria to the cytosol, (3) the induction of DNA fragmentation, (4) the induction of classic changes in cell morphology, and (5) the appearance of TUNEL-positive cells. Incubation of CNS pericytes with dexamethasone induced the appearance of apoptotic cells in a time- and dose-dependent manner. Pericytes express immunologically detectable glucocorticoid receptors, and addition of the glucocorticoid receptor antagonist mifepristone inhibited dexamethasone-induced pericyte apoptosis. That pericytes undergo apoptosis in response to dexamethasone suggests that the regulatory function of this steroid may be important in vascular development and that pericyte apoptotic cell death may accompany vascular regression. Deregulation of pericyte involvement in vascular homeostasis and hemostasis may result in clinical disease.


Assuntos
Apoptose/fisiologia , Glucocorticoides/farmacologia , Microcirculação/citologia , Microcirculação/crescimento & desenvolvimento , Neovascularização Fisiológica/fisiologia , Pericitos/fisiologia , Animais , Anexina A5/metabolismo , Apoptose/efeitos dos fármacos , Barreira Hematoencefálica/efeitos dos fármacos , Barreira Hematoencefálica/fisiologia , Diferenciação Celular/efeitos dos fármacos , Diferenciação Celular/fisiologia , Membrana Celular/efeitos dos fármacos , Membrana Celular/metabolismo , Sobrevivência Celular/efeitos dos fármacos , Sobrevivência Celular/fisiologia , Células Cultivadas , Citocromos c/metabolismo , Fragmentação do DNA/efeitos dos fármacos , Fragmentação do DNA/fisiologia , Dexametasona/farmacologia , Relação Dose-Resposta a Droga , Feminino , Glucocorticoides/metabolismo , Microcirculação/efeitos dos fármacos , Mifepristona/farmacologia , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/metabolismo , Neovascularização Fisiológica/efeitos dos fármacos , Pericitos/efeitos dos fármacos , Transporte Proteico/efeitos dos fármacos , Transporte Proteico/fisiologia , Ratos , Ratos Sprague-Dawley , Receptores de Glucocorticoides/efeitos dos fármacos , Receptores de Glucocorticoides/metabolismo
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