Multiplex Polymerase Chain Reaction Reveals Unique Trends in Pathogen and Parasitoid Infestations of Alfalfa Leafcutting Brood Cells.

The alfalfa leafcutting bee Megachile rotundata Fabricius (HYMENOPTERA: Megachilidae) is an important pollinator for multiple agricultural seed commodities in the United States. M. rotundata is a solitary cavity nesting bee that forms brood nests where its larvae can develop. During the developmental stages of growth, brood can be preyed upon by multiple different fungal pathogens and insect predators and parasitoids, resulting in the loss of the developing larvae. Larval loss is a major concern for alfalfa (Medicago sativa L.) seed producers because they rely on pollination services provided by M. rotundata. Reduced pollination rates result in lower yields and increased production costs. In the present study, we examined the taxonomic composition of organisms found within M. rotundata brood cells using a multiplex PCR assay which was developed for the detection of bacterial, fungal, and invertebrate pests and pathogens of M. rotundata larvae. Known pests of M. rotundata were detected, including members of the fungal genus Ascosphaera, the causative agent of chalkbrood. The presence of multiple Ascosphaera species in a single brood cell was observed, with potential implications for chalkbrood disease management. The multiplex assay also identified DNA from more than 2,400 total species, including multiple predators and pathogenetic species not previously documented in association with M. rotundata brood cells.

Changes in emergence phenology, fatty acid composition, and xenobiotic-metabolizing enzyme expression is associated with increased insecticide resistance in the Colorado potato beetle.

The Colorado potato beetle (Leptinotarsa decemlineata) is a major agricultural pest of solanaceous crops. An effective management strategy employed by agricultural producers to control this pest species is the use of systemic insecticides. Recent emphasis has been placed on the use of neonicotinoid insecticides. Despite efforts to curb resistance development through integrated pest management approaches, resistance to neonicotinoids in L. decemlineata populations continues to increase. One contributing factor may be alterations in insect fatty acids, which have multiple metabolic functions and are associated with the synthesis of xenobiotic-metabolizing enzymes to mitigate the effects of insecticide exposure. In this study, we analyzed the fatty acid composition of L. decemlineata populations collected from an organic production field and from a commercially managed field to determine if fatty acid composition varied between the two populations. We demonstrate that a population of L. decemlineata that has a history of systemic neonicotinoid exposure (commercially managed) has a different lipid composition and differential expression of known metabolic detoxification mechanisms relative to a population that has not been exposed to neonicotinoids (organically managed). The fatty acid data indicated an upregulation of Δ6 desaturase in the commercially managed L. decemlineata population and suggest a role for eicosanoids and associated metabolic enzymes as potential modulators of insecticide resistance. We further observed a pattern of delayed emergence within the commercially managed population compared with the organically managed population. Variations in emergence timing together with specific fatty acid regulation may significantly influence the capacity of L. decemlineata to develop insecticide resistance.

Underappreciated Utility of the Purse-String Suture in Head and Neck Skin Cancer Defect Reconstruction.

BACKGROUND: The purse-string suture (PSS) is a simple, reversible method for reconstructing skin cancer defects. Its utility may be underappreciated in head and neck reconstructive surgery. OBJECTIVE: To evaluate the utility of the PSS as an adjunct to the reconstructive ladder when reconstructing head and neck skin cancer defects. MATERIALS AND METHODS: This prospective nonrandomized cohort included 109 consecutive adult patients with head and neck defects resulting from skin cancer resection. The PSS was placed in every patient after resection. Patients were evaluated before and after suture placement, and final reconstructive methods were recorded. RESULTS: The PSS resulted in a mean defect area reduction of 77.1% (p < .001) and was used in the final reconstruction in 79 (72.5%) patients. The PSS reduced the number of patients requiring adjacent tissue transfer (11), regional tissue transfer (3), and free tissue transfer (1) by 69.4%, 70%, and 80%, respectively. Fifty patients underwent reconstruction in the operating room. After intraoperative placement of the PSS, it was determined that 22 (44.0%) of these defects could have been reconstructed in the clinic (p = .003). CONCLUSION: The PSS dramatically reduces defect size, simplifies reconstructive techniques, and often permits reconstruction to be performed in the clinic rather than the operating room.

Upper Lid Thick Skin Blepharoplasty.

While many of the basic tenants of upper lid blepharoplasty remain constant regardless of skin type, the thick-skinned eyelid patient requires special consideration. The brow may be naturally lower in the thick-skinned patient. These patients are more prone to having the brow pulled downward while attempting to remove redundant skin. There may also be more fat in the medial and central compartments. There may be fat in a lateral compartment overlying the lacrimal gland. Patient's expectations for a deep lid sulcus and complete excision of redundant skin may not be possible. They are more prone to an observable scar, a small dog ear at the lateral wound edge, and prolonged postoperative lid edema. Patients with lifelong upper lid fullness must get some input from significant others because their upper face aesthetic will change. In these patients, the eyelid surgery is not a rejuvenation, but a creation.

Using targeted sequencing and TaqMan approaches to detect acaricide (bifenthrin, bifenazate, and etoxazole) resistance associated SNPs in Tetranychus urticae collected from peppermint fields and hop yards.

Tetranychus urticae (Koch) is an economically important pest of many agricultural commodities world-wide. Multiple acaricides, including bifenazate, bifenthrin, and extoxazole, are currently registered to control T. urticae. However, populations of T. urticae in many different growing regions have developed acaricide resistance through multiple mechanisms. Within T. urticae, single nucleotide polymorphisms (SNPs) have been documented in different genes which are associated with acaricide resistance phenotypes. The detection of these mutations through TaqMan qPCR has been suggested as a practical, quick, and reliable tool to inform agricultural producers of acaricide resistance phenotypes present within their fields and have potential utility for making appropriate acaricide application and integrated pest management decisions. Within this investigation we examined the use of a TaqMan qPCR-based approach to determine genotypes which have been previously associated with acaricide resistance in field-collected populations of T. urticae from peppermint fields and hop yards in the Pacific Northwest of the United States and confirmed the results with a multiplex targeted sequencing. The results suggest that a TaqMan qPCR approach accurately genotypes T. urticae populations for SNPs that have been linked to Bifenazate, Bifenthrin, and Etoxazole resistance. The results also demonstrated that different populations of mites in Washington and Idaho displayed varying frequencies of the examined SNPs. While we were able to detect the SNPs associated with the examined acaricides, the mutation G126S was not an appropriate or accurate indicator for bifenazate resistance.

Examining Historical Rates of Leafcutting Bee Brood Cell Pathogens, Parasitoids, and Predators to Establish Baseline Infectivity Rates for Alfalfa Seed Growers.

The alfalfa leafcutting bee Megachile rotundata (Fabricius) (Hymenoptera: Megachilidae) is the primary pollinator for the alfalfa seed industry. It is a solitary cavity nesting bee that utilizes leaf lined brood cells provisioned with pollen for larval development and pupation into the adult stage. During development, multiple pathogens, parasitoids, and predators can prey upon or use the larvae as a host, resulting in the loss of the future adult bee. As such, the presence of invertebrate pests and fungal pathogens presents a major concern for commercial alfalfa seed growers. In the present study, we used historic data from the Parma Cocoon Diagnostic Laboratory to determine baseline rates of pathogens, parasitoids, and predators of Megachile rotundata brood cells and used this analysis to determine cutoffs for management practices to inform growers when the purchase of new bee stocks should be considered. Additionally, we compared the presence of chalkbrood, predators, and parasitoids in samples collected from both grower-produced stocks and newly purchased Canadian bees. The results of the investigation provide historic averages of the presence of chalkbrood, predators, and parasitoids, show a significant increase in chalkbrood and predators in 2007-2011, and find a significant difference in rates of chalkbrood and predators between samples from Canadian suppliers and grower stocks. We speculate that these differences may have resulted from economic conditions that increased the cost of Canadian Megachile rotundata cells and likely resulted in increased reliance on 2nd-year U.S. grower stocks and subsequently increased infection rates during this time period.

'Candidatus Phytoplasma asteris' subgroups display distinct disease progression dynamics during the carrot growing season.

Aster Yellows phytoplasma (AYp; 'Candidatus Phytoplasma asteris') is an obligate bacterial pathogen that is the causative agent of multiple diseases in herbaceous plants. While this phytoplasma has been examined in depth for its disease characteristics, knowledge about the spatial and temporal dynamics of pathogen spread is lacking. The phytoplasma is found in plant's phloem and is vectored by leafhoppers (Cicadellidae: Hemiptera), including the aster leafhopper, Macrosteles quadrilineatus Forbes. The aster leafhopper is a migratory insect pest that overwinters in the southern United States, and historical data suggest these insects migrate from southern overwintering locations to northern latitudes annually, transmitting and driving phytoplasma infection rates as they migrate. A more in-depth understanding of the spatial, temporal and genetic determinants of Aster Yellows disease progress will lead to better integrated pest management strategies for Aster Yellows disease control. Carrot, Daucus carota L., plots were established at two planting densities in central Wisconsin and monitored during the 2018 growing season for Aster Yellows disease progression. Symptomatic carrots were sampled and assayed for the presence of the Aster Yellows phytoplasma. Aster Yellows disease progression was determined to be significantly associated with calendar date, crop density, location within the field, and phytoplasma subgroup.

Degree day models to forecast the seasonal phenology of Drosophila suzukii in tart cherry orchards in the Midwest U.S.

Spotted-wing drosophila, Drosophila suzukii (Matsumura) (Diptera: Drosophilidae), is an invasive economic pest of soft-skinned and stone fruit across the globe. Our study establishes both a predictive generalized linear mixed model (GLMM), and a generalized additive mixed model (GAMM) of the dynamic seasonal phenology of D. suzukii based on four years of adult monitoring trap data in Wisconsin tart cherry orchards collected throughout the growing season. The models incorporate year, field site, relative humidity, and degree days (DD); and relate these factors to trap catch. The GLMM estimated a coefficient of 2.21 for DD/1000, meaning for every increment of 1000 DD, trap catch increases by roughly 9 flies. The GAMM generated a curve based on a cubic regression smoothing function of DD which approximates critical DD points of first adult D. suzukii detection at 1276 DD, above average field populations beginning at 2019 DD, and peak activity at 3180 DD. By incorporating four years of comprehensive seasonal phenology data from the same locations, we introduce robust models capable of using DD to forecast changing adult D. suzukii populations in the field leading to the application of more timely and effective management strategies.

Genetic Variation Among Geographically Disparate Isolates of Aster Yellows Phytoplasma in the Contiguous United States.

Aster Yellows phytoplasma (AYp; Candidatus Phytoplasma asteris) is associated with diseases of herbaceous plants, including ornamentals and important commercial vegetable and grain crops. The aster leafhopper (ALH; Macrosteles quadrilineatus Forbes) is the predominant vector of these bacteria, though other leafhopper species can acquire and transmit AYp. Potentially inoculative leafhoppers are reported to overwinter in the southern United States and migrate to northern latitudes in the spring. Examining the genetic similarities and differences in AYp associated with southern and northern populations of ALH may provide insight into the role that migrating ALH play in AYp disease development. To investigate similarities among geographically distinct populations of ALH and characterize the variation in AYp associated within these populations, we identified genetic variations in subgroup designation and the relative proportions of secreted AY-WB proteins from field-collected populations of AYp isolated from ALH from select locations in the southern (Arkansas, Kansas, Oklahoma, and Texas) and the northern United States (Wisconsin) in 2016, 2017, and 2018. Isolated phytoplasma were tested for variation of AYp genotypes, numbers of potentially inoculative (AYp-positive) ALH, and presence of specific AYp virulence (effector) genes. Geographically distinct populations of ALH collected in northern and southern regions were similar in CO1 genotype but carried different proportions of AYp genotypes. While similar AYp strains were detected in geographically distinct locations, the proportion of each genotype varied over time.

Reconstruction of the Forehead and Scalp.

Tissue inelasticity and the hair-bearing nature of the scalp and forehead pose unique challenges during reconstruction. A thorough understanding of the surgical anatomy of the scalp and forehead is paramount for optimal reconstructive outcomes. Primary wound closure is usually preferred over secondary intention healing and skin grafting. Use of dermal alternatives and tissue expansion are adjunctive therapies to facilitate scalp wound closure. Local skin and soft tissue flaps are commonly used for most small to medium defects; however, microsurgical free tissue transfer can be considered for large full-thickness skin defects of the forehead and scalp.

Widespread detections of neonicotinoid contaminants in central Wisconsin groundwater.

Neonicotinoids are a popular and widely-used class of insecticides whose heavy usage rates and purported negative impacts on bees and other beneficial insects has led to questions about their mobility and accumulation in the environment. Neonicotinoid compounds are currently registered for over 140 different crop uses in the United States, with commercial growers continuing to rely heavily on neonicotinoid insecticides for the control of key insect pests through a combination of in-ground and foliar applications. In 2008, the Wisconsin Department of Agriculture, Trade and Consumer Protection (DATCP) began testing for neonicotinoids in groundwater test wells in the state, reporting detections of one or more neonicotinoids in dozens of shallow groundwater test wells. In 2011, similar detection levels were confirmed in several high-capacity overhead center-pivot irrigation systems in central Wisconsin. The current study was initiated to investigate the spatial extent and magnitude of neonicotinoid contamination in groundwater in and around areas of irrigated commercial agriculture in central Wisconsin. From 2013-2015 a total of 317 samples were collected from 91 unique high-capacity irrigation wells and tested for the presence of thiamethoxam (TMX), a neonicotinoid, using enzyme-linked immunosorbent assays. 67% of all samples were positive for TMX at a concentration above the analytical limit of quantification (0.05 µg/L) and 78% of all wells tested positive at least once. Mean detection was 0.28 µg/L, with a maximum detection of 1.67 µg/L. Five wells had at least one detection exceeding 1.00 µg/L. Furthermore, an analysis of the spatial structure of these well detects suggests that contamination profiles vary across the landscape, with differences in mean detection levels observed from landscape (25 km), to farm (5 km), to individual well (500 m) scales. We also provide an update of DATCP's neonicotinoid monitoring in Wisconsin's shallow groundwater test wells and private potable wells for the years 2011-2017.

Utility of nasal swab and age in detecting methicillin-resistant Staphylococcus aureus in pediatric head and neck abscesses.

OBJECTIVE: To identify risk factors associated with the presence of methicillin-resistant Staphylococcus aureus (MRSA) in surgical cultures taken from incision and drainage (I&D) of head and neck abscesses in the pediatric population. STUDY DESIGN: Retrospective case series. METHODS: All patients under 18 years of age with a head and neck abscess requiring I&D from 2009 to 2015 were reviewed. MRSA nasal swab cultures were taken from all patients upon hospitalization. Surgical cultures were obtained from all patients and correlated with MRSA nasal swab results. Univariate and multivariate logistic regression was performed, and odds ratios (ORs) along with descriptive statistics were analyzed. RESULTS: Of a total of 272 patients, there were 68 (25%) MRSA-positive abscesses. The majority (86.8%) of these abscesses were in children under 2 years of age. Overall, 12 (4.4%) presented with positive admission MRSA nasal swabs. Of these, 91.7% had MRSA-positive abscess cultures. Decreasing age in years showed an OR of 1.650 (P < 0.001) for MRSA-positive abscess, with children less than 1 year old having the highest OR of 10.74 (P < 0.001). CONCLUSION: Younger age and MRSA nasal colonization were two statistically significant risk factors for developing an MRSA abscess of the head and neck. This study demonstrates a high positive predictive value for MRSA-positive neck abscesses when nasal swab screenings were MRSA-positive (91.7%). Children under 2 years of age-especially those under 1 year of age-or those with MRSA nasal colonization can be considered a high-risk population that may benefit from empiric antibiotics against MRSA for head and neck abscesses. LEVEL OF EVIDENCE: 4. Laryngoscope, 127:2407-2412, 2017.

Disinfection of rigid nasal endoscopes following in vitro contamination with Staphylococcus aureus, Streptococcus pneumoniae, Pseudomonas aeruginosa, and Haemophilus influenzae.

IMPORTANCE: If not adequately cleaned, rigid nasal endoscopes (RNEs) have the potential to cause iatrogenic cross-contamination. OBJECTIVE: To test the efficacy of various disinfection methods in reducing bacterial load on RNEs in vitro. DESIGN AND SETTING: In vitro model. INTERVENTIONS: Staphylococcus aureus, Streptococcus pneumoniae, Pseudomonas aeruginosa, and Haemophilus influenzae contamination was separately induced on RNEs in vitro. Two experimental sets were completed. The RNEs were disinfected using the following protocols: 30-second scrub with antimicrobial soap (ABS) and water, 30-second scrub with 70% isopropyl alcohol (IA), 30-second scrub with ABS followed by 30-second scrub with IA, 30-second scrub with germicidal cloth, isolated 5-minute soak in an enzymatic soap solution, 5- and 10-minute soaks in ortho-phthalaldehyde, 0.55%, solution (Cidex OPA), and isolated 30-second rinse with tap water, all with 30-second precleaning and postcleaning rinses with tap water. Two sets of experiments (experiment sets A and B) were carried out with a 30-second tap water rinse after inoculation of each RNE. This was followed by immediate cleaning in set A and a 1-hour air-dry delay in set B. Otherwise there were no differences in the disinfection protocols between sets for each method noted. MAIN OUTCOMES AND MEASURES: Effectiveness of various disinfection protocols in cleaning rigid nasal endoscopes experimentally inoculated with bacteria commonly found in the upper aerodigestive tract. Positive cultures following disinfection indicated ineffective or incomplete disinfection. RESULTS: Most cleaning methods were effective in eliminating S aureus, S pneumoniae, and H influenzae from the scopes following experimental contamination. Continued growth of P aeruginosa was found after all of the disinfection trials in experiment set A with the exception of a 10-minute immersion in Cidex OPA, and in set B except for the 10-minute Cidex OPA immersion and ABS plus IA trials. CONCLUSIONS AND RELEVANCE: Most cleaning methods used in our trials appear to properly disinfect RNEs after in vitro inoculation with S aureus, S pneumoniae, and H influenzae. However, it appears that disinfectants may be less effective in cleaning rigid scopes experimentally inoculated with P aeruginosa. There is a paucity of published data regarding cross-contamination during rigid nasal endoscopy, and these results should guide future studies and to some extent practice to avoid iatrogenic spread of contamination.