Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) testing for essential food production workers: evolving thinking, pilot testing, and lessons learned.

An essential part of U.S. coronavirus disease 2019 (COVID-19) critical infrastructure is the country's food-production workforce. Keeping food-production workers safe during the COVID-19 pandemic has meant added workplace protections. Protection guidance came early from the Federal Government. Absent from such guidance were strategies to screen for the causative virus. Without viral screening, some food companies had outbreaks; some facilities had to close. Companies interested in viral screening had to devise their own strategies. One company devised a strategy having three main goals: (1) detecting asymptomatic infections, before opportunity for spread; (2) identifying workplace clusters, to indicate potential protection breakdowns; and (3) comparing company results to community infection rates. The company decided on pilot screenings at two U.S. production plants. Screenings involved mandatory viral testing (through reverse transcription polymerase chain reaction) and optional antibody testing (both immunoglobulins G and M). Pilot screenings showed benefits along with limitations: (1) detecting asymptomatic infections, but at questionably relevant time points; (2) identifying infection clusters, but with uncertain sites of transmission; (3) showing relatively low rates of infection, but absent details for meaningful community comparisons. Establishing a worker screening process was an enormous undertaking. Company employees had to stretch job roles and were distracted form usual responsibilities. Whether other companies would find sufficient benefits to justify similar screening is unclear. Moving forward, new Federal leadership could provide greater support for, and assistance with, worker screenings. In addition, new technologies could make future screenings more feasible and valuable. The worker screening experience from this pandemic offers learnings the next.

101 Dothideomycetes genomes: A test case for predicting lifestyles and emergence of pathogens.

Dothideomycetes is the largest class of kingdom Fungi and comprises an incredible diversity of lifestyles, many of which have evolved multiple times. Plant pathogens represent a major ecological niche of the class Dothideomycetes and they are known to infect most major food crops and feedstocks for biomass and biofuel production. Studying the ecology and evolution of Dothideomycetes has significant implications for our fundamental understanding of fungal evolution, their adaptation to stress and host specificity, and practical implications with regard to the effects of climate change and on the food, feed, and livestock elements of the agro-economy. In this study, we present the first large-scale, whole-genome comparison of 101 Dothideomycetes introducing 55 newly sequenced species. The availability of whole-genome data produced a high-confidence phylogeny leading to reclassification of 25 organisms, provided a clearer picture of the relationships among the various families, and indicated that pathogenicity evolved multiple times within this class. We also identified gene family expansions and contractions across the Dothideomycetes phylogeny linked to ecological niches providing insights into genome evolution and adaptation across this group. Using machine-learning methods we classified fungi into lifestyle classes with >95 % accuracy and identified a small number of gene families that positively correlated with these distinctions. This can become a valuable tool for genome-based prediction of species lifestyle, especially for rarely seen and poorly studied species.

Gender differences in the order of appearance of elbow ossification centres.

BACKGROUND: The predictable order of appearance of elbow secondary ossification centres in children is important in interpreting elbow radiographs, most commonly in the context of trauma. The usual sequence of appearance of these ossification centres is given by the acronym CRITOL, but exceptions have been described and are recognised as normal variants. AIM: To investigate the extent to which the appearance of the elbow secondary ossification centres follows a predictable sequence, and to establish the incidence of exceptions to the usual CRITOL order. METHODS: Two-stage retrospective review of 421 elbow radiographs in children at our centre. RESULTS: Of 64 children with two visible ossification centres, there was a 23% overall variant incidence (49 CR, 15 CI). Twenty-eight children had four visible ossification centres, with an overall variant incidence of 32% (19 CRIT, 9 CRIO). The variants were significantly more common in girls than in boys ( p < 0.001). CONCLUSION: Whilst the majority of radiographs remained consistent with the described CRITOL sequence, variance in this order was seen in a quarter of children with two visible ossification centres, and a third of children with four visible ossification centres. Incidence of variance was much more common in girls, reaching statistical significance. Awareness of these normal variations, particularly in girls, should help to avoid misinterpretation.

Value of the portal venous phase in evaluation of treated hepatocellular carcinoma following transcatheter arterial chemoembolisation.

AIM: To evaluate the utility of the portal venous phase on multiphasic computed tomography (CT) after treatment of hepatocellular carcinoma (HCC) with trans-arterial chemoembolisation (TACE). MATERIALS AND METHODS: This was a retrospective review of patients who underwent TACE for HCC between 1 April 2012 and 21 December 2014, with appropriate multiphasic, pre- and post-procedural CT examinations. The maximum non-contrast, arterial phase, and portal venous phase attenuation values of the tumour and tumour bed were evaluated within a region of interest (ROI), with values adjusted against background hepatic parenchyma. Linear regression analyses were performed for both the arterial and venous phases, to assess the level of enhancement and to determine if the venous phase had additional value in this setting. RESULTS: A total of 86 cases from 51 patients were reviewed. All pre-procedural CT examinations of lesions demonstrated arterial phase enhancement with portal venous and delayed phase washout compatible with HCC. The post-procedural CT examinations following TACE revealed expected decreased arterial enhancement. Sixty-five cases (76%) showed persistent non-enhancement on the portal venous phase following embolisation therapy. A total of 21 cases (24%), however, demonstrated progressive portal venous hyper enhancement. Linear regression analysis demonstrated a statistical significance between the difference in maximal arterial and portal venous enhancement in these cases. CONCLUSION: Following TACE, the treated lesion may demonstrate portal venous phase hyper-enhancement within the tumour bed. As such, full attention should be given to these images for comprehensive evaluation of tumour response following treatment.

The mid-point transverse process to pleura (MTP) block: a new end-point for thoracic paravertebral block.

Current descriptions of thoracic paravertebral block techniques require the needle tip to be anterior to the superior costotransverse ligament. We hypothesised that an injection point midway between the posterior border of the transverse process and the pleura would result in spread to the paravertebral space. We completed bilateral injections of 5 ml methylene blue 0.2% midway between the posterior border of the transverse process and the pleura at T2, T4, T6, T8 and T10 in three unembalmed cadavers. The presence of methylene blue dye at the nerve root in the paravertebral space, the corresponding intercostal nerve and sympathetic chain at the level of injection, and at additional levels, was examined. We identified the superior costotransverse ligament, pleural displacement and spread to the erector spinae plane. We describe two case reports using this technique in patients. Our cadaver results and clinical cases demonstrate that, with the exception of cadaver 1, an injection point midway between the posterior border of the transverse process and pleura consistently achieved spread of dye at least to the paravertebral space at the level of injection, and frequently to adjacent levels. This may be a plausible explanation for the landmark technique's inability to reliably achieve a multilevel block. We describe a new ultrasound-guided technique for a single level paravertebral block.

Failed landings after laying hen flight in a commercial aviary over two flock cycles.

Many egg producers are adopting alternative housing systems such as aviaries that provide hens a tiered cage and a litter-covered open floor area. This larger, more complex environment permits expression of behaviors not seen in space-limited cages, such as flight. Flight is an exercise important for strengthening bones; but domestic hens might display imperfect flight landings due to poor flight control. To assess the potential implications of open space, we evaluated the landing success of Lohmann white laying hens in a commercial aviary. Video recordings of hens were taken from 4 aviary sections at peak lay, mid lay and end lay across two flock cycles. Observations were made in each focal section of all flights throughout the day noting flight origin and landing location (outer perch or litter) and landing success or failure. In Flock 1, 9.1% of all flights failed and 21% failed in Flock 2. The number of flights decreased across the laying cycle for both flocks. Proportionally more failed landings were observed in the double row sections in Flock 2. Collisions with other hens were more common than slipping on the ground or colliding with aviary structures across sections and flocks. More hens slipped on the ground and collided with physical structures at peak lay for Flock 2 than at other time points. More collisions with other hens were seen at mid and end lay than at peak lay for Flock 2. Landings ending on perches failed more often than landings on litter. These results indicate potential for flight-related hen injuries in aviary systems resulting from failed landings, which may have implications for hen welfare and optimal system design and management.

The evolution of novelty in conserved genes; evidence of positive selection in the Drosophila fruitless gene is localised to alternatively spliced exons.

There has been much debate concerning whether cis-regulatory or coding changes are more likely to produce evolutionary innovation or adaptation in gene function, but an additional complication is that some genes can dramatically diverge through alternative splicing, increasing the diversity of gene function within a locus. The fruitless gene is a major transcription factor with a wide range of pleiotropic functions, including a fundamental conserved role in sexual differentiation, species-specific morphology and an important influence on male sexual behaviour. Here, we examine the structure of fruitless in multiple species of Drosophila, and determine the patterns of selective constraint acting across the coding region. We found that the pattern of selection, estimated from the ratio of non-synonymous to synonymous substitutions, varied considerably across the gene, with most regions of the gene evolutionarily conserved but with several regions showing evidence of divergence as a result of positive selection. The regions that showed evidence of positive selection were found to be localised to relatively consistent regions across multiple speciation events, and are associated with alternative splicing. Alternative splicing may thus provide a route to gene diversification in key regulatory loci.

Weight maintenance over 12 months after weight loss resulting from participation in a 12-week randomised controlled trial comparing all meal provision to self-directed diet in overweight adults.

BACKGROUND: The results of weight maintenance after initial weight loss are reported infrequently, although, when they have been reported, the outcomes are generally poor and weight regain is common. METHODS: After an initial 12-week randomised intervention comparing all meal provision against a self-directed energy restriction, participants re-consented to participate in a follow-on study. Participants were given the option to choose to continue with the same dietary intervention (either all meal provision (provided free of charge) or self-directed diet) or change to the other diet for a further 12 weeks. Participants were followed up at 4-weekly intervals during both intervention periods (a total of 24 weeks), with a final follow up at 12 months. RESULTS: Eighty-five out of 86 individuals who completed the original 12-week randomised phase chose to continue on to the follow-up study. No significant differences in further weight loss between groups (P = 0.138) [mean (SEM): -3.4% (1.1%) for all meal provision only; -3.4% (0.6%) self-directed then all meal provision; -1.1% (1.2%) all meal provision then self-directed] were seen after a further 12 weeks. Meal provision for a total of 24 weeks resulted in 67% of individuals losing at least 10% body weight. The groups switching from self-directed dieting to meal provision (or vice versa) were the only groups to have a lower mean weight at 12 months than at the start of the follow-on study. CONCLUSIONS: Structured support for 24 weeks followed by 28 weeks of self-care can result in weight maintenance, with initial weight loss maintained at 12 months from enrolling on a 12-week weight loss intervention, with a 12-week follow-on period.

Weight loss in a UK commercial all meal provision study: a randomised controlled trial.

BACKGROUND: Effective approaches are needed to address the increasing prevalence of overweight and obesity. The present study investigated whether all meal provision was a more effective and acceptable method for weight loss than a self-directed diet. METHODS: This randomised controlled trial recruited 112 men and women with a body mass index in the range 27-35 kg m(-2), who had no comorbidities, from the local area of Hull. Participants were randomised to receive either meal provision or follow a self-directed diet for a 12-week period that resulted in an estimated 2928 kJ day(-1) (700 kcal day(-1)) deficit. A dietitian supervised both dietary interventions. RESULTS: At 12 weeks [mean (SEM)], percentage weight loss in the meal provision group was 6.6% (0.5%) compared to 4.3% (0.6%) for those on the self-directed diet. In terms of clinically relevant weight loss, 61% of participants lost 5% or more of their body weight with meal provision compared to 22% on the self-directed diet (P < 0.001). Weight loss was associated with wellbeing in both groups. Attrition was less apparent with 7% of those participants receiving meal provision withdrawing from the study compared to 41% of those following the self-directed diet (P < 0.001). CONCLUSIONS: Meal provision was a more effective and accepted method for weight loss over a 12-week period compared to a self-directed diet. This may in part represent the difference between being given the meal provision food free of charge. However, longer-term maintenance studies need to be undertaken to ascertain their effects on the maintenance of weight loss.

Using Reddit as a recruitment strategy for addiction science research.

Reddit is a forum-based social media and message board platform that has been used in the social sciences as a recruitment source of human subject data. In addiction science, Reddit remains a viable but underutilized tool, compared to other websites (e.g., Amazon's Mechanical Turk, Prolific). The purpose of this commentary is to provide a rationale and recommendations for the successful use of Reddit for addiction science researchers interested in adding it as a recruitment tool. We provide an example of how Reddit can be used to target specific populations of interest, such as individuals struggling with depression or alcohol use disorder. Last, we discuss the limitations of Reddit as a research tool and some considerations for future research to help promote effective use of the platform.

Variable number of tandem repeat markers in the genome sequence of Mycosphaerella fijiensis, the causal agent of black leaf streak disease of banana (Musa spp).

We searched the genome of Mycosphaerella fijiensis for molecular markers that would allow population genetics analysis of this plant pathogen. M. fijiensis, the causal agent of banana leaf streak disease, also known as black Sigatoka, is the most devastating pathogen attacking bananas (Musa spp). Recently, the entire genome sequence of M. fijiensis became available. We screened this database for VNTR markers. Forty-two primer pairs were selected for validation, based on repeat type and length and the number of repeat units. Five VNTR markers showing multiple alleles were validated with a reference set of isolates from different parts of the world and a population from a banana plantation in Costa Rica. Polymorphism information content values varied from 0.6414 to 0.7544 for the reference set and from 0.0400 and 0.7373 for the population set. Eighty percent of the polymorphism information content values were above 0.60, indicating that the markers are highly informative. These markers allowed robust scoring of agarose gels and proved to be useful for variability and population genetics studies. In conclusion, the strategy we developed to identify and validate VNTR markers is an efficient means to incorporate markers that can be used for fungicide resistance management and to develop breeding strategies to control banana black leaf streak disease. This is the first report of VNTR-minisatellites from the M. fijiensis genome sequence.

Genetic structure of Phaeosphaeria nodorum populations in the north-central and midwestern United States.

Stagonospora nodorum blotch, caused by Phaeosphaeria nodorum, is considered one of the most destructive foliar diseases of wheat in the United States. However, relatively little is known about the population biology of this fungus in the major wheat-growing regions of the central United States. To rectify this situation, 308 single-spore isolates of P. nodorum were analyzed from 12 populations, five from hard red spring wheat cultivars in Minnesota and North Dakota and seven from soft red winter wheat in Indiana and Ohio. The genetic structure of the sampled populations was determined by analyzing polymorphisms at five microsatellite or simple-sequence repeat (SSR) loci and the mating type locus. Although a few clones were identified, most P. nodorum populations had high levels of gene (H(S) = 0.175 to 0.519) and genotype (D = 0.600 to 0.972) diversity. Gene diversity was higher among isolates collected from spring wheat cultivars in North Dakota and Minnesota (mean H(S) = 0.503) than in those from winter wheat cultivars in Indiana and Ohio (H(S) = 0.269). Analyses of clone-corrected data sets showed equal frequencies of both mating types in both regional and local populations, indicating that sexual recombination may occur regularly. However, significant gametic disequilibrium occurred in three of the four populations from North Dakota, and there was genetic differentiation both within and among locations. Genetic differentiation between the hard red spring and soft red winter wheat production regions was moderate (F(ST) = 0.168), but whether this is due to differences in wheat production or to geographical variation cannot be determined. These results suggest that sexual reproduction occurs in P. nodorum populations in the major wheat-growing regions of the central United States, and that geographically separated populations can be genetically differentiated, reflecting either restrictions on gene flow or selection.

Adsorption and binding dynamics of graphene-supported phospholipid membranes using the QCM-D technique.

We report on the adsorption dynamics of phospholipid membranes on graphene-coated substrates using the quartz crystal microbalance with dissipation monitoring (QCM-D) technique. We compare the lipid vesicle interaction and membrane formation on gold and silicon dioxide QCM crystal surfaces with their graphene oxide (GO) and reduced (r)GO coated counterparts, and report on the different lipid structures obtained. We establish graphene derivative coatings as support surfaces with tuneable hydrophobicity for the formation of controllable lipid structures. One structure of interest formed is lipid monolayer membranes which were formed on rGO, which are otherwise challenging to produce. We also demonstrate and monitor biotin-avidin binding on such a membrane, which will then serve as a platform for a wide range of biosensing applications. The QCM-D technique could be extended to both fundamental studies and applications of other covalent and non-covalent interactions in 2-dimensional materials.

Compartmentalization of neuronal and peripheral serotonin synthesis in Drosophila melanogaster.

In Drosophila, one enzyme (Drosophila tryptophan-phenylalanine hydroxylase, DTPHu) hydroxylates both tryptophan to yield 5-hydroxytryptophan, the first step in serotonin synthesis, and phenylalanine, to generate tyrosine. Analysis of the sequenced Drosophila genome identified an additional enzyme with extensive homology to mammalian tryptophan hydroxylase (TPH), which we have termed DTRHn. We have shown that DTRHn can hydroxylate tryptophan in vitro but displays differential activity relative to DTPHu when using tryptophan as a substrate. Recent studies in mice identified the presence of two TPH genes, Tph1 and Tph2, from distinct genetic loci. Tph1 represents the non-neuronal TPH gene, and Tph2 is expressed exclusively in the brain. In this article, we show that DTRHn is neuronal in expression and function and thus represents the Drosophila homologue of Tph2. Using a DTRHn-null mutation, we show that diminished neuronal serotonin affects locomotor, olfactory and feeding behaviors, as well as heart rate. We also show that DTPHu functions in vivo as a phenylalanine hydroxylase in addition to its role as the peripheral TPH in Drosophila, and is critical for non-neuronal developmental events.

Effective treatment of an elderly patient with Gaucher's disease and Parkinsonism: a case report of 24 months' oral substrate reduction therapy with miglustat.

We report here the results of 24 months' treatment with oral miglustat of a patient with mild-to-moderate Gaucher's disease (GD) and Parkinsonism. The patient's progressive Parkinsonian tremor, in addition to restricted vascular access, necessitated switching treatment for GD from intravenously infused enzyme replacement therapy (ERT) that had been administered for the previous 7 years. With control of haematological parameters and markers of GD activity improved or maintained and no notable adverse effects, miglustat treatment proved an effective and well-tolerated therapeutic alternative to ERT. Oral miglustat should be considered for the treatment of patients with type I GD and concurrent movement disorders who are unsuitable for ERT.

Molecular neurogenetics of sexual differentiation and behaviour.

Sex and death. Two things that come once in a lifetime. Only after death you're not nauseous. - Woody Allen 'Sleeper'. The brain and nervous system functions that underlie sex-specific behaviour are of obvious importance to all animals, including humans. To understand behaviour related to sex, it is important to distinguish those aspects that are controlled genetically. Much of the recent progress in studies of the molecular neurogenetics of sexual differentiation and behaviour has come from the use of genetically tractable organisms (i.e. fruitflies and nematode worms) that exhibit a full range of sexually dimorphic phenotypes.

Reverse genetics of Drosophila brain structure and function.

A set of molecular genetic technologies are described, which will have far reaching consequences for the study of brain structure, function and development in Drosophila melanogaster. Site selected mutagenesis (a PCR-based screen for P-element insertion events) allows insertion mutants to be isolated for any cloned gene, and is being used in this laboratory to ask questions about the rolls of particular cellular components in learning and memory. Transposants have been isolated in genes encoding a regulatory (RI) and a catalytic (DCO) subunit of cAMP-dependent protein kinase, and in a gene encoding a Gi-like alpha subunit. The alternative use of I factors is described. The PKA RI homozygous mutants display a significant decrement in initial learning ability. Enhancer-trap strategies, for which the GAL-4 P-element system is particularly convenient, allow the identification of genes expressed in the developing fly brain. Strategies for the efficient detection of such events are described.

Intravenous enzyme replacement therapy: better in home or hospital?

This article evaluates satisfaction with enzyme replacement therapy (ERT) at home and at hospital in adult patients with Fabry and Gaucher diseases. A questionnaire was developed and sent to 34 patients with Fabry disease who were receiving ERT with agalsidase alfa (Replagal) and to 49 patients with type I Gaucher disease who were receiving ERT with glucocerebrosidase (Cerezyme). Of the 45 returned questionnaires, 20 were from patients with Fabry disease and 25 from patients with Gaucher disease. Hospital treatment visits were reported as stressful by 18 patients (40%), whereas only 4 (9%) patients reported that home therapy was stressful. Both groups of patients adjusted well to receiving home-based therapy. Nearly all of the patients with Fabry disease (19 patients, 95%) and Gaucher disease (21 patients, 84%) preferred home-based therapy. Treatment in the home was reported as more comfortable, less stressful, more effective and had less impact on family life. Only 4 (9%) patients chose to continue receiving infusions in hospital. The majority of patients with Fabry disease and Gaucher disease found home-based therapy to be more convenient and less stressful than hospital-based therapy.

Female receptivity phenotype of icebox mutants caused by a mutation in the L1-type cell adhesion molecule neuroglian.

Relatively little is known about the genes and brain structures that enable virgin female Drosophila to make the decision to mate or not. Classical genetic approaches have identified several mutant females that have a reluctance-to-mate phenotype, but most of these have additional behavioral defects. However, the icebox (ibx) mutation was previously reported to lower the sexual receptivity of females, without apparently affecting any other aspect of female behavior. We have shown that the ibx mutation maps to the 7F region of the Drosophila X chromosome to form a complex complementation group with both lethal and viable alleles of neuroglian (nrg). The L1-type cell adhesion molecule encoded by nrg consists of six immunoglobulin-like domains, five fibronectin-like domains, one transmembrane domain and one alternatively spliced intracellular domain. The ibx strain has a missense mutation causing a glycine-to-arginine change at amino acid 92 in the first immunoglobulin domain of nrg. Defects in the central brain of ibx mutants are similar to those observed in another nrg mutant, central brain deranged(1) (ceb(1)). However, both ceb(1) homozygous and ceb(1)/ibx heterozygous females are receptive. The expression of a transgene containing the non-neural isoform of nrg rescues both the receptivity and the brain structure phenotypes of ibx females.