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1.
J Insect Sci ; 23(6)2023 Nov 01.
Article in English | MEDLINE | ID: mdl-38055948

ABSTRACT

Because nontarget, beneficials, like insect pollinators, may be exposed unintentionally to insecticides, it is important to evaluate the impact of chemical controls on the behaviors performed by insect pollinators in field trials. Here we examine the impact of a portable mosquito repeller, which emits prallethrin, a pyrethroid insecticide, on honey bee foraging and recruitment using a blinded, randomized, paired, parallel group trial. We found no significant effect of the volatilized insecticide on foraging frequency (our primary outcome), waggle dance propensity, waggle dance frequency, and feeder persistency (our secondary outcomes), even though an additional deposition study confirmed that the treatment device was performing appropriately. These results may be useful to consumers that are interested in repelling mosquitos, but also concerned about potential consequences to beneficial insects, such as honey bees.


Subject(s)
Bees , Behavior, Animal , Culicidae , Insecticides , Pyrethrins , Animals , Animal Communication , Appetitive Behavior/drug effects , Bees/drug effects , Behavior, Animal/drug effects , Insect Repellents/pharmacology , Insecticides/pharmacology , Pyrethrins/pharmacology
2.
Emerg Infect Dis ; 24(3): 553-557, 2018 03.
Article in English | MEDLINE | ID: mdl-29460762

ABSTRACT

We detected Cache Valley virus in Aedes japonicus, a widely distributed invasive mosquito species, in an Appalachian forest in the United States. The forest contained abundant white-tailed deer, a major host of the mosquito and virus. Vector competence trials indicated that Ae. j. japonicus mosquitoes can transmit this virus in this region.


Subject(s)
Aedes/virology , Bunyamwera virus , Bunyaviridae Infections/epidemiology , Bunyaviridae Infections/transmission , Animals , Appalachian Region/epidemiology , Bunyamwera virus/classification , Bunyamwera virus/genetics , Bunyaviridae Infections/virology , Geography , Humans , Public Health Surveillance
3.
Article in English | MEDLINE | ID: mdl-36589865

ABSTRACT

Mortality caused by passive resin transfluthrin diffusers (∼5 mg AI per 24 h release rate) suspended in small 2-person tents was measured for colony-reared sentinel pyrethroid susceptible Aedes aegypti and Culex quinquefasciatus female mosquitoes, as well as a pyrethroid-resistant strain of Aedes aegypti, in a USA military field camp scenario. Mortality effects were investigated for impact by factors such as sentinel cage location (inside tent, tent doorway and outside tent), exposure time (15, 30, 45 and 60 min), and environmental temperature (°C), all of which were examined over an 8-week period. Analyses determined there was a significant interaction between mosquito strain and transfluthrin susceptibility, with the two susceptible strains experiencing significantly greater mean mortality than the resistant Ae. aegypti strain. Significant differences were likewise observed between the mosquito strains over the 8-week study period, where study week and temperature were both positively correlated with an increase in observed mean mosquito mortality. Mosquito proximity to the transfluthrin diffusers was also influenced by week and showed that sentinel cage placement in the environment demonstrates different mortality measurements, depending on the environmental conditions. The length of exposure to transfluthrin, however, was determined to not significantly impact transfluthrin efficacy on the examined mosquito strains, although increased exposure did result in increased susceptible strain mortality. These results suggest that transfluthrin is highly effective in causing mortality against susceptible Ae. aegypti and Cx. quinquefasciatus mosquitoes under field conditions but is minimally effective against pyrethroid-resistant Ae. aegypti mosquitoes. Transfluthrin-infused devices are influenced by environmental factors that can combine to impact mosquito mortality in the field.

4.
J Am Mosq Control Assoc ; 37(1): 20-27, 2021 03 01.
Article in English | MEDLINE | ID: mdl-33857320

ABSTRACT

The effects of 3 plant species (Cornus florida [dogwood], rhododendron X 'Chionoides' [rhododendron], and Ilex opaca [American holly]), 4 insecticide treatments (Demand® CS [lambda-cyhalothrin] at 6.25 ml[AI]/liter; Talstar® Professional [bifenthrin] at 7.81 ml[AI]/liter, and Suspend® Polyzone® [deltamethrin] at 11.72 ml[AI]/liter, and water), and 2 physiological states (blood-fed and unfed) were evaluated for knockdown (1 h) and mortality (24 h) against female Aedes albopictus over an 8-wk sampling period. Analyses determined that there was a significant interaction between the tested plant species and the insecticides evaluated. Significant differences were likewise observed between the insecticide treatments for unfed Ae. albopictus females, with Demand CS demonstrating the highest knockdown and mortality rates (from >90% to >10% at wk 8 and >95% to ∼50% at wk 8, respectively), followed by Talstar Professional (from >75% to <10% at wk 2 and >90% to <10% at wk 2, respectively) and Suspend Polyzone (from >20% to <10% at wk 8 and >25% to >50% at wk 8, respectively). All treatments were no longer significant for knockdown or mortality at the end of the 8-wk timeframe. Significant differences were also observed between insecticide treatments for blood-fed Ae. albopictus females; Demand CS showed high knockdown and mortality rates (from 100% to ∼50% at wk 8 and 100% to >60% at wk 8, respectively), Suspend Polyzone rates were similar to Demand CS (from >80% to ∼50% at wk 8 and ∼90% to >65% at wk 8, respectively), and both were followed by Talstar Professional (from 100% to <10% at wk 4 and 100% to <20% at wk 4, respectively). All tested pyrethroid sprays showed a significant increase in effectiveness against recently blood-fed Ae. albopictus females, as compared to the unfed females. These results suggest that Demand CS can be used as an effective barrier spray against Ae. albopictus adults due to the limited impact of target foliage, its long-term efficacy under environmental conditions, and its continued effectiveness regardless of the blood meal status of the target mosquito.


Subject(s)
Aedes , Insecticides , Mosquito Control , Mosquito Vectors , Nitriles , Pyrethrins , Animals , Cornus/growth & development , Female , Ilex/growth & development , Rhododendron/growth & development
5.
Mult Scler Int ; 2021: 5588335, 2021.
Article in English | MEDLINE | ID: mdl-34258067

ABSTRACT

BACKGROUND: Activities of daily living and quality of life (QOL) are hindered by upper extremity (UE) impairments experienced by individuals with multiple sclerosis (iMS). The Nine-Hole Peg Test (9-HPT) is most frequently used to measure UE function. However, it does not measure peoples' ability to perform routine tasks in daily life and may not be useful in iMS who cannot pick up the pegs utilized in the 9-HPT. Therefore, we evaluated three measures to explore a more comprehensive assessment of UE function: Upper Extremity Function Scale (UEFS), Action Research Arm Test (ARAT), and the 9-HPT. The objectives were to quantitatively assess the relationship between these measures of UE function, understand if the measures correlate with QOL as calculated by the MS Quality of Life-54 (MSQOL-54), and to determine differences in the measures based on employment status. METHODS: 112 (79 female) iMS were prospectively recruited for this descriptive correlational study. Inclusion criteria were as follows: confirmed diagnosis of MS or clinically isolated syndrome, age ≥ 18 years, and ability to self-consent. All statistical analyses including Spearman's correlation coefficient (r s ) and Kruskal-Wallis tests were performed using SPSS. RESULTS: A moderate correlation (r s = -0.51; p < 0.001) was found between the ARAT and 9-HPT scores for the more impaired hand. Likewise, a moderate correlation was found between UEFS and the physical health composite scores (PHCSs) of MSQOL-54 (r s = -0.59; p < 0.001). Finally, performances on ARAT, 9-HPT, and UEFS differed between the employed individuals and those on long-term disability (p = 0.007, p < 0.001, and p = 0.001). CONCLUSION: The UEFS moderately correlated with the QOL measure, and considering the UESF is a patient-reported outcome, it could be used to complement routinely captured measures of assessing UE function. Further study is warranted to determine which measure, or combination of measures, is more sensitive to changes in UE function over time.

6.
J Am Mosq Control Assoc ; 34(4): 281-290, 2018 12.
Article in English | MEDLINE | ID: mdl-31442145

ABSTRACT

The effect of 5 plant species (arborvitae [Thuja occidentalis], boxwood [Buxus sp., Japanese honeysuckle [Lonicera japonica], rhododendron [Rhododendron sp.], and zebra grass [Miscanthus sinensis]) and 2 rates of lambda-cyhalothrin (3.13 ml and 6.25 ml active ingredient [AI]/liter) on knockdown (1 h) and mortality (24 h) of adult female Aedes albopictus was evaluated over an 8-wk period. A significant difference in knockdown was observed between the 2 rates of lambda-cyhalothrin on the 5 plant species, with the highest proportion of knockdown observed on zebra grass and rhododendron treated at the higher rate. Although mortality was ≥60% and 85% on the 5 plant species at the low and high rates of lambda-cyhalothrin, respectively, a significant difference between the 2 rates was only observed on boxwood and Japanese honeysuckle (P < 0.0001). We also tested the residual toxicity of 3 barrier sprays (lambda-cyhalothrin, bifenthrin, and deltamethrin) and evaluated the efficacy of a short (5-min) exposure to the insecticides on knockdown and mortality of adults over time. Significantly higher knockdown was observed with lambda-cyhalothrin compared with bifenthrin and deltamethrin (P < 0.0001). Mean knockdown was ∼98%, 92%, and 20% for lambda-cyhalothrin, bifenthrin, and deltamethrin, respectively, at week 2, and ∼98%, 0%, and 44%, respectively, 8 wk after treatments were applied. Adult mortality from the 3 chemical treatments, however, remained above 90% throughout the study. Lastly, the trends in mean proportion of knockdown were similar for mosquitoes exposed for either 5 min or 24 h to the 3 chemicals. An overall decline in mean mortality over time, however, was observed for mosquitoes exposed for 5 min to the chemicals compared with mortality from the 24-h exposure. The results suggest that lambda-cyhalothrin can be an effective barrier spray treatment against Ae. albopictus adults because its efficacy is limited little by plant species, it has long residual toxicity, and it is effective following only 5 min of exposure.


Subject(s)
Aedes , Insecticides , Mosquito Control , Nitriles , Pyrethrins , Animals , Dose-Response Relationship, Drug , Female , Mosquito Control/methods , Plant Physiological Phenomena , Plants/classification , Time Factors
7.
J Biol Chem ; 281(14): 9011-7, 2006 Apr 07.
Article in English | MEDLINE | ID: mdl-16455649

ABSTRACT

All species of Mycobacteria synthesize distinctive cell walls that are rich in phosphatidylinositol mannosides (PIMs), lipomannan (LM), and lipoarabinomannan (LAM). PIM glycolipids, having 2-4 mannose residues, can either be channeled into polar PIM species (with 6 Man residues) or hypermannosylated to form LM and LAM. In this study, we have identified a Mycobacterium smegmatis gene, termed lpqW, that is required for the conversion of PIMs to LAM and is highly conserved in all mycobacteria. A transposon mutant, Myco481, containing an insertion near the 3' end of lpqW exhibited altered colony morphology on complex agar medium. This mutant was unstable and was consistently overgrown by a second mutant, represented by Myco481.1, that had normal growth and colony characteristics. Biochemical analysis and metabolic labeling studies showed that Myco481 synthesized the complete spectrum of apolar and polar PIMs but was unable to make LAM. LAM biosynthesis was restored to near wild type levels in Myco481.1. However, this mutant was unable to synthesize the major polar PIM (AcPIM6) and accumulated a smaller intermediate, AcPIM4. Targeted disruption of the lpqW gene and complementation of the initial Myco481 mutant with the wild type gene confirmed that the phenotype of this mutant was due to loss of LpqW. These studies suggest that LpqW has a role in regulating the flux of early PIM intermediates into polar PIM or LAM biosynthesis. They also suggest that AcPIM4 is the likely branch point intermediate in polar PIM and LAM biosynthesis.


Subject(s)
Genes, Bacterial , Lipopolysaccharides/biosynthesis , Mycobacterium smegmatis/genetics , Mycobacterium smegmatis/physiology , Phosphatidylinositols/metabolism , Cell Membrane/physiology , Gene Expression Regulation, Bacterial , Mutation , Mycobacterium smegmatis/growth & development , Mycobacterium smegmatis/pathogenicity , Phenotype , Virulence
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