Publications by authors named "Yocum G"

Social bees have been extensively studied for their gut microbial functions, but the significance of the gut microbiota in solitary bees remains less explored. Solitary bee, females provision their offspring with pollen from various plant species, harboring a diverse microbial community that colonizes larvae guts. The is the most abundant microbe, but evidence concerning the effects of and other provision microbes on growth and survival are lacking.

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The solitary bee Osmia lignaria is a native pollinator in North America with growing economic importance. The life cycle of O. lignaria provides a unique opportunity to compare the physiological and molecular mechanisms underlying two ecologically contrasting dormancies within the same species.

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Insects exposed to constant low temperatures (CLT) exhibit high rates of mortality as well as a variety of sublethal effects. In many species, interruptions of CLT with brief pulses of warm temperatures (fluctuating thermal regimes, FTR) lead to increases in survival and fewer sublethal effects. However, we still lack a complete understanding of the physiological mechanisms activated during FTR.

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The Colorado potato beetle, Leptinotarsa decemlineata, (Coleoptera: Chrysomelidae) is an economically important pest insect of potatoes. Understanding how the mechanisms driving its invasiveness vary between sexes will be critical for developing modern control methods. However, the currently available methods for sexing adult Colorado potato beetles are either inefficient or unsuitable for projects that require RNA as an input, like those measuring gene expression.

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Novel gamma-aminobutyric acid receptor (GABAR) ligands structurally related to imidazobenzodiazepine MIDD0301 were synthesized using spiro-amino acid N-carboxyanhydrides (NCAs). These compounds demonstrated increased resistance to phase 2 metabolism and avoided the formation of a 6H isomer. Compound design was guided by molecular docking using the available crystal structure of the αβγ GABAR and correlated with in vitro binding data.

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The success of agriculture relies on healthy bees to pollinate crops. Commercially managed pollinators are often kept under temperature-controlled conditions to better control development and optimize field performance. One such pollinator, the alfalfa leafcutting bee, , is the most widely used solitary bee in agriculture.

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Megachile rotundata (F.) is an important pollinator of alfalfa in the United States. Enhancing landscapes with wildflowers is a primary strategy for conserving pollinators and may improve the sustainability of M.

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Asthma is a common respiratory disease characterized, in part, by excessive airway smooth muscle (ASM) contraction (airway hyperresponsiveness). Various GABAR (γ-aminobutyric acid type A receptor) activators, including benzodiazepines, relax ASM. The GABAR is a ligand-operated Cl channel best known for its role in inhibitory neurotransmission in the central nervous system.

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Within the United States and Canada, the primary pollinator of alfalfa is the alfalfa leafcutting bee (ALCB), . Our previous findings showed that overwintering conditions impacted gene expression profile in ALCB prepupae that entered diapause early in the season. However, ALCB are a bivoltine species, which begs the question of whether bees entering diapause later in the season also show this trend.

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MIDD0301 is being developed as an oral drug to relax airway smooth muscle (ASM) and reduce lung inflammation in asthma. We report a comparative study of MIDD0301 and its S isomer (MIDD0301S), and found that the compounds have equivalent affinity for γ-aminobutyric acid type A receptor (GABA R) expressed in rat brain, with half maximal inhibitory concentration values of 25.1 and 26.

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We report the modification of MIDD0301, an imidazodiazepine GABA receptor (GABAR) ligand, using two alkyl substituents. We developed PI310 with a 6-(4-phenylbutoxy)hexyl chain as used in the long-acting β2-agonist salmeterol and PI320 with a poly(ethylene glycol) chain as used to improve the brain:plasma ratio of naloxegol, a naloxone analogue. Both imidazodiazepines showed affinity toward the GABAR binding site of clonazepam, with IC values of 576 and 242 nM, respectively.

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Diapause is a complex physiological phenomenon that allows insects to weather stressful environmental conditions. The regulation of diapause is accordingly complex, including signaling pathways that involve both small RNA and mRNA and affect the cell cycle, stress resistance, and developmental timing. Transposable elements, mobile genetic elements that replicate within the genome, are also thought to be stress responsive and regulated by the small RNA pathway.

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Megachile rotundata exhibits a facultative prepupal diapause but the cues regulating diapause initiation are not well understood. Possible cues include daylength and temperature. Megachile rotundata females experience changing daylengths over the nesting season that may influence diapause incidence in their offspring through a maternal effect.

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Variation in body size has important implications for physical performance and fitness. For insects, adult size and morphology are determined by larval growth and metamorphosis. Female blue orchard bees, Osmia lignaria, (Say) provision a finite quantity of food to their offspring.

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Diapause is a non-feeding state that many insects undergo to survive the winter months. With fixed resources, overall metabolism and insulin signaling (IIS) are maintained at low levels, but whether those change in response to seasonal temperature fluctuations remains unknown. The focus of this study was to determine 1) how genes in the insulin signaling pathway vary throughout diapause and 2) if that variation changes in response to temperature.

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Interrupting the spring incubation of Megachile rotundata (F.) with a period of low-temperature storage for synchronizing the bees' emergence with crop bloom is an essential part of M. rotundata management.

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We report the relaxation of methacholine-constricted airways with nebulized MIDD0301, a positive allosteric γ-aminobutyric acid type A receptor (GABAR) modulator. The therapeutic efficacy of nebulized MIDD0301 in reducing airway resistance was investigated in spontaneous breathing mice using a whole-body plethysmograph and in unconscious mice using a forced oscillation technique. Prophylactic nebulized MIDD0301 reduced subsequent methacholine-induced bronchoconstriction in ovalbumin and house dust mite allergic asthma models and in normal mice.

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Airway smooth muscle hyperresponsiveness associated with chronic airway inflammation leads to the typical symptoms of asthma including bronchoconstriction and wheezing. Asthma severity is associated with airway inflammation; therefore, reducing airway inflammation is an important therapeutic target. Gelsolin is an actin capping and severing protein that has been reported to be involved in modulation of the inflammatory response.

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Article Synopsis
  • The study investigates how the quantity and quality of diet affect honeybee caste development, focusing on the distinction between queen and worker bees.
  • The researchers found that larvae receiving a high quantity of diet were similar to commercially raised queens, highlighting the importance of diet quantity over the specific nutritional composition.
  • It was concluded that providing large amounts of food during the larval stages can influence the development of queen characteristics, challenging previous beliefs about when caste determination occurs.
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The temperature of the nest influences fitness in cavity-nesting bees. Females may choose nest cavities that mitigate their offspring's exposure to stressful temperatures. This study aims to understand how cavity temperature impacts the nesting preference of the solitary bee Megachile rotundata (Fabricius) under field conditions.

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Asthma, a common disorder associated with airway inflammation and hyperresponsiveness, remains a significant clinical burden in need of novel therapeutic strategies. Patients are increasingly seeking complementary and alternative medicine approaches to control their symptoms, including the use of natural products. Ginger, a natural product that we previously demonstrated acutely relaxes airway smooth muscle (ASM), has long been reported to possess anti-inflammatory properties, although a precise mechanistic understanding is lacking.

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TMEM16A (anoctamin 1) is an important calcium-activated chloride channel in airway smooth muscle (ASM). We have previously shown that TMEM16A antagonists such as benzbromarone relax ASM and have proposed TMEM16A antagonists as novel therapies for asthma treatment. However, TMEM16A is also expressed on airway epithelium, and TMEM16A agonists are being investigated as novel therapies for cystic fibrosis.

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In insects, prolonged exposure to unseasonably low temperatures can lead to detrimental physiological effects known as chill injury. Changes to active and passive transport across epithelia during chilling likely drive the collapse of ion gradients, metabolic imbalance and potentially oxidative stress. In the alfalfa leafcutting bee, Megachile rotundata transcriptomic evidence provides support for these responses at the level of gene expression, but variable expression profiles between life stages in M.

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Insects exposed to low temperature stress can experience chill injury, but incorporating fluctuating thermoprofiles increases survival and blocks the development of sub-lethal effects. The specific parameters required for a protective thermoprofile are poorly understood, because most studies test a limited range of thermoprofiles. For example, thermoprofiles with a wave profile may perform better than a square profile, but these two profiles are rarely compared.

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