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AIM: To investigate whether Mediterranean tall fescue (Lolium arundinaceum(Schreb.) Darbysh. (synFestuca arundinacea)) infected with selected fungal endophytes (Epichloë coenophiala(formerlyNeotyphodium coenophialum)) caused equine fescue oedema when grown in New Zealand, and to examine the pathological changes associated with this intoxication. METHODS: Horses were grazed on Mediterranean tall fescue that was infected with the endophytes AR542 (n=2), or AR584 (n=3), or Mediterranean tall fescue that was endophyte-free (n=2). Blood samples were taken up to 7 days after the start of feeding to detect changes in concentrations of total protein in serum and packed cell volume. Any horse showing clinical evidence of disease was subject to euthanasia and necropsy. RESULTS: Within 6 days, both horses grazing fescue infected with AR542 became depressed and lethargic. One horse grazing fescue infected with endophyte AR584 became depressed within a 5-day feeding period while another horse in this group died shortly after being removed from the AR584 pasture. The third horse in this group did not develop clinical signs within the 5-day feeding period. However, haemoconcentration and hypoproteinaemia was detected in all horses grazing Mediterranean tall fescue that was infected by AR542 or AR584 endophyte. No abnormalities were observed in horses grazing fescue that was endophyte-free. Necropsy examination was performed on two horses grazing fescue infected with AR542 and one horse grazing fescue infected with AR584. All three horses had marked oedema of the gastrointestinal tract. Histologically, the oedema was accompanied by large numbers of eosinophils, but no necrosis. CONCLUSIONS: Horses grazing Mediterranean tall fescue that was infected by AR542 or AR584 developed hypoproteinaemia and haemoconcentration, most likely due to leakage of plasma proteins into the gastrointestinal tract. This suggests that these selected endophytes produce a compound that is toxic to horses, although the toxic principle is currently unknown. CLINICAL RELEVANCE: Mediterranean tall fescue that is infected by AR542 or AR584 should not be fed to horses in New Zealand. This intoxication should be considered in horses in which a rapid onset of hypoproteinaemia and haemoconcentration is detected. This intoxication should also be considered if marked gastrointestinal oedema is observed. [ABSTRACT FROM PUBLISHER]

Trust between healthcare workers is a fundamental component of effective, interprofessional collaboration and teamwork. However, little is known about how this trust is built, particularly when healthcare workers are distributed (i.e., not co-located and lack a shared electronic health record). We interviewed 39 healthcare workers who worked with proximal and distributed colleagues to care for patients with diabetic foot ulcers and analyzed transcripts using content analysis. Generally, building trust was a process that occurred over time, starting with an introduction and proceeding through iterative cycles of communication and working together to coordinate care for shared patients. Proximal, compared to distributed, dyads had more options available for interactions which, in turn, facilitated communication and working together to build trust. Distributed healthcare workers found it more difficult to develop trusting relationships and relied heavily on individual initiative to do so. Few effective tools existed at the level of interprofessional collaborations, teams, or broader healthcare systems to support trust between distributed healthcare workers. With increasing use of distributed interprofessional collaborations and teams, future efforts should focus on fostering this critical attribute.

Whole-genome duplication is considered an important speciation mechanism in plants. However, its effect on reproductive isolation between higher cytotypes is not well understood. We used backcrosses between different ploidy levels and surveys of mixed-ploidy contact zones to determine how reproductive barriers differed with cytotype across a polyploid complex. We backcrossed F1 hybrids derived from 2X-4X and 4X-6X crosses in the Campanula rotundifolia autopolyploid complex, measured backcross fitness, and estimated backcross DNA cytotype. We then sampled four natural mixed-ploidy contact zones (two 2X-4X and two 4X-6X), estimated ploidy, and genotyped individuals across each contact zone. Reproductive success and capacity for gene flow was markedly lower for 2X-4X than 4X-6X hybrids. In fact, 3X hybrids could not backcross; all 2X-4X backcross progeny resulted from neotetraploid F1 hybrids. Further, no 3X individuals were found in 2X-4X contact zones, and 2X and 4X individuals were genetically distinct. By contrast, backcrosses of 5X hybrids were relatively successful, particularly when crossed to 6X individuals. In 4X-6X contact zones, 5X individuals and aneuploids were common and all cytotypes were largely genetically similar and spatially intermixed. Taken together, these results provide strong evidence that reproduction is low between 2X and 4X cytotypes, primarily occurring via unreduced gamete production, but that reproduction and gene flow are ongoing between 4X and 6X cytotypes. Further, it suggests whole-genome duplication can result in speciation between diploids and polyploids, but is less likely to create reproductive barriers between different polyploid cytotypes, resulting in two fundamentally different potentials for speciation across polyploid complexes., Competing Interests: None declared., (© 2021 The Authors. Ecology and Evolution published by John Wiley & Sons Ltd.)

Systematic computational studies of pericyclic Diels-Alder-type reactions between aminoborane (F 3 C) 2 B = N(CH 3 ) 2 , 1 , and all permutations of substituted cyclopentadienes c -C 5 R 1 R 2 R 3 R 4 R 5a R 5b (R = H, CH 3 , CF 3 , F) allow isolation of substitutional effects on Gibbs free energy barrier heights and reaction Gibbs free energies. The effects appear to be additive in all cases. Substitution at positions 5a and 5b always increases barriers and reaction energies, an effect explained by steric interactions between substituents and the aminoborane moiety. For cases R = CH 3 , regioselectivities differ from those expected from canonical organic chemistry predictions. Frontier molecular orbital calculations suggest this arises from the extreme polarization of the π interaction in 1 . For cases R = CF 3 , the 2/3-substitution comparison accords with canon, but the 1/4-substitution comparison does not. This appears to arise from a combination of electronic and steric issues. For cases R = F, many of the reactions are exergonic, in contrast to the cases R = CH 3 , CF 3 . Additionally, fluorine substitution at positions 2 and 4 has a barrier-lowering effect. Frontier molecular orbital calculations support an orbital-based preference for formation of 2- and 4-substituted "meta" products rather than "ortho/para" products.

Most land plants are now known to be ancient polyploids that have rediploidized. Diploidization involves many changes in genome organization that ultimately restore bivalent chromosome pairing and disomic inheritance, and resolve dosage and other issues caused by genome duplication. In this review, we discuss the nature of polyploidy and its impact on chromosome pairing behavior. We also provide an overview of two major and largely independent processes of diploidization: cytological diploidization and genic diploidization/fractionation. Finally, we compare variation in gene fractionation across land plants and highlight the differences in diploidization between plants and animals. Altogether, we demonstrate recent advancements in our understanding of variation in the patterns and processes of diploidization in land plants and provide a road map for future research to unlock the mysteries of diploidization and eukaryotic genome evolution.

When differentiated lineages come into contact, their fates depend on demographic and reproductive factors. These factors have been well-studied in taxa of the same ploidy, but less is known about sympatric lineages that differ in ploidy, particularly with respect to demographic factors. We assessed prezygotic, postzygotic, and total reproductive isolation in naturally pollinated arrays of diploid-tetraploid and tetraploid-hexaploid population mixes of Campanula rotundifolia by measuring pollinator transitions, seed yield, germination rate, and proportion of hybrid offspring. Four frequencies of each cytotype were tested, and pollinators consistently overvisited rare cytotypes. Seed yield and F1 hybrid production were greater in 4X-6X arrays than 2X-4X arrays, whereas germination rates were similar, creating two distinct patterns of reproductive isolation. In 2X-4X arrays, postzygotic isolation was near complete (3% hybrid offspring), and prezygotic isolation associated with pollinator preference is expected to facilitate the persistence of minority cytotypes. However, in 4X-6X arrays where postzygotic isolation permitted hybrid formation (44% hybrids), pollinator behavior drove patterns of reproductive isolation, with rare cytotypes being more isolated and greater gene flow expected from rare into common cytotypes. In polyploid complexes, both the specific cytotypes in contact and local cytotype frequency, likely reflecting spatial demography, will influence likelihood of gene exchange., (© 2020 The Authors. Evolution © 2020 The Society for the Study of Evolution.)

Background: Rural Americans with diabetic foot ulcers (DFUs) face a 50% increased risk of major amputation compared to their urban counterparts. We sought to identify health system barriers contributing to this disparity., Methods: We interviewed 44 participants involved in the care of rural patients with DFUs: 6 rural primary care providers (PCPs), 12 rural specialists, 12 urban specialists, 9 support staff, and 5 patients/caregivers. Directed content analysis was performed guided by a conceptual model describing how PCPs and specialists collaborate to care for shared patients., Results: Rural PCPs reported lack of training in wound care and quickly referred patients with DFUs to local podiatrists or wound care providers. Timely referrals to, and subsequent collaborations with, rural specialists were facilitated by professional connections. However, these connections often were lacking between rural providers and urban specialists, whose skills were needed to optimally treat patients with high acuity ulcers. Urban referrals, particularly to vascular surgery or infectious disease, were stymied by 1) time-consuming processes, 2) negative provider interactions, and 3) multiple, disconnected electronic health record systems. Such barriers ultimately detracted from rural PCPs' ability to focus on medical management, as well as urban specialists' ability to appropriately triage referrals due to lacking information. Subsequent collaboration between providers also suffered as a result., Conclusions: Poor connections across rural and urban healthcare systems was described as the primary health system barrier driving the rural disparity in major amputations. Future interventions focusing on mitigating this barrier could reduce the rural disparity in major amputations.

Objective: Multiple single-center studies have reported significant reductions in major amputations among patients with diabetic foot ulcers after initiation of multidisciplinary teams. The purpose of this study was to assess the association between multidisciplinary teams (ie, two or more types of clinicians working together) and the risk of major amputation and to compile descriptions of these diverse teams., Methods: We searched PubMed, Scopus, Cumulative Index to Nursing and Allied Health, and Cochrane Central Register of Controlled Trials from inception through May 24, 2019 for studies reporting the association between multidisciplinary teams and major amputation rates for patients with diabetic foot ulcers. We included original studies if ≥50% of the patients seen by the multidisciplinary team had diabetes, they included a control group, and they reported the effect of a multidisciplinary team on major amputation rates. Studies were excluded if they were non-English language, abstracts only, or unpublished. We used the five-domain Systems Engineering Initiative for Patient Safety Model to describe team composition and function and summarized changes in major amputation rates associated with multidisciplinary team care. A meta-analysis was not performed because of heterogeneity across studies, their observational designs, and the potential for uncontrolled confounding (PROSPERO No. 2017: CRD42017067915)., Results: We included 33 studies, none of which were randomized trials. Multidisciplinary team composition and functions were highly diverse. However, four elements were common across teams: teams were composed of medical and surgical disciplines; larger teams benefitted from having a "captain" and a nuclear and ancillary team member structure; clear referral pathways and care algorithms supported timely, comprehensive care; and multidisciplinary teams addressed four key tasks: glycemic control, local wound management, vascular disease, and infection. Ninety-four percent (31/33) of studies reported a reduction in major amputations after institution of a multidisciplinary team., Conclusions: Multidisciplinary team composition was variable but reduced major amputations in 94% of studies. Teams consistently addressed glycemic control, local wound management, vascular disease, and infection in a timely and coordinated manner to reduce major amputation for patients with diabetic foot ulcerations. Care algorithms and referral pathways were key tools to their success., (Copyright © 2019 Society for Vascular Surgery. All rights reserved.)

Rubus (Rosaceae) comprises more than 500 species with additional commercially cultivated raspberries and blackberries. The most recent (> 100 years old) global taxonomic treatment of the genus defined 12 subgenera; two subgenera were subsequently described and some species were rearranged. Intra- and interspecific ploidy levels and hybridization make phylogenetic estimation of Rubus challenging. Our objectives were to estimate the phylogeny of 94 taxonomically and geographically diverse species and three cultivars using chloroplast DNA sequences and target capture of approximately 1,000 low copy nuclear genes; estimate divergence times between major Rubus clades; and examine the historical biogeography of species diversification. Target capture sequencing identified eight major groups within Rubus . Subgenus Orobatus and Subg. Anoplobatus were monophyletic, while other recognized subgenera were para- or polyphyletic. Multiple hybridization events likely occurred across the phylogeny at subgeneric levels, e.g., Subg. Rubus (blackberries) × Subg. Idaeobatus (raspberries) and Subg. Idaeobatus × Subg. Cylactis (Arctic berries) hybrids. The raspberry heritage within known cultivated blackberry hybrids was confirmed. The most recent common ancestor of the genus was most likely distributed in North America. Multiple distribution events occurred during the Miocene (about 20 Ma) from North America into Asia and Europe across the Bering land bridge and southward crossing the Panamanian Isthmus. Rubus species diversified greatly in Asia during the Miocene. Rubus taxonomy does not reflect phylogenetic relationships and subgeneric revision is warranted. The most recent common ancestor migrated from North America towards Asia, Europe, and Central and South America early in the Miocene then diversified. Ancestors of the genus Rubus may have migrated to Oceania by long distance bird dispersal. This phylogeny presents a roadmap for further Rubus systematics research. In conclusion, the target capture dataset provides high resolution between species though it also gave evidence of gene tree/species tree and cytonuclear discordance. Discordance may be due to hybridization or incomplete lineage sorting, rather than a lack of phylogenetic signal. This study illustrates the importance of using multiple phylogenetic methods when examining complex groups and the utility of software programs that estimate signal conflict within datasets., (Copyright © 2019 Carter, Liston, Bassil, Alice, Bushakra, Sutherland, Mockler, Bryant and Hummer.)

Objective: SBP variability may be a target for mitigating end-organ damage associated with vascular disease. We evaluated the relationship between increased SBP variability and risk of incident diabetic foot ulceration., Methods: Using a nested case-control design, we followed patients diagnosed with diabetes and treated within the US Department of Veterans Affairs Healthcare system for development of a diabetic foot ulcer (event) between 2006 and 2010. Each case was randomly matched to up to five controls based on age, sex, race/ethnicity, and calendar time. SBP variability was computed using at least three blood pressure measurements from the year preceding the event. The association between SBP variability and foot ulceration was examined using conditional logistic regression. Potential protective effects of calcium channel blockers, which blunt SBP variability, were also explored., Results: The study sample included 51 111 cases and 129 247 controls. Compared with those in quartile 1 (lowest variability), patients in quartiles 2-4 had higher adjusted odds ratios for diabetic foot ulcer development: 1.11 (95% CI 1.07-1.16), 1.20 (95% CI 1.15-1.25), 1.29 (95% CI 1.24-1.34) (P for trend <0.001). Calcium channel blockers were associated with reduced risks of ulceration for those without peripheral vascular disease (OR = 0.87, 95% CI 0.84-0.90, P < 0.001) or neuropathy (OR = 0.85, 95% CI 0.82-0.89, P < 0.001) in adjusted subgroup analyses., Conclusion: This study describes a graded relationship between SBP variability and risk of diabetic foot ulceration, providing a potential new and modifiable target to reduce this common complication.

Premise of the Study: Both intrinsic and extrinsic factors contribute to a species distribution. Among plants, the extrinsic effects of glaciation and intrinsic effects of whole genome duplication are powerful drivers of biogeographical patterns, but the interplay of these factors is poorly understood. Here, we investigate the roles glaciation and whole-genome duplication have played in the evolution of the widespread polyploid complex Campanula rotundifolia., Methods: We assessed the cytotype of 37 populations that spanned the geographic and cytotypic range of the C. rotundifolia complex. We constructed a chloroplast phylogeny for these populations and used RAD-seq to create nuclear phylogenies and networks for a subset of 23 populations; and estimated divergence times of major clades using Bayesian estimation of substitution rates., Key Results: Campanula rotundifolia originated in south-central Europe and underwent range expansion throughout much of Europe and North America. Multiple genome duplications have occurred in C. rotundifolia-at least two tetraploid and three hexaploid formations., Conclusions: Nuclear and chloroplast phylogenies are largely congruent with a history of populations surviving glacial maxima in known Pleistocene refugia in Europe and North America. Divergent European clades are consistent with two disjunct glacial refugia within Europe. North America was colonized by hexaploids derived from Western European lineages. A glacial refugium in Midwestern North America likely facilitated post-glacial recolonization of North America and limited genetic divergence. These results implicate both glaciation and whole-genome duplication as contributing factors to the extant biogeography of C. rotundifolia., (© 2018 Botanical Society of America.)

Premise of the Study: Angiosperm species often shift from self-incompatibility to self-compatibility following population bottlenecks. Across the range of a species, population bottlenecks may result from multiple factors, each of which may affect the geographic distribution and magnitude of mating-system shifts. We describe how intercontinental dispersal and genome duplication facilitate loss of self-incompatibility., Methods: Self and outcross pollinations were performed on plants from 24 populations of the Campanula rotundifolia polyploid complex. Populations spanned the geographic distribution and three dominant cytotypes of the species (diploid, tetraploid, hexaploid)., Key Results: Loss of self-incompatibility was associated with both intercontinental dispersal and genome duplication. European plants were largely self-incompatible, whereas North American plants were intermediately to fully self-compatible. Within both European and North American populations, loss of self-incompatibility increased as ploidy increased. Ploidy change and intercontinental dispersal both contributed to loss of self-incompatibility in North America, but range expansion did not affect self-incompatibility within Europe or North America., Conclusions: When species are subject to population bottlenecks arising through multiple factors, each factor can contribute to self-incompatibility loss. In a widespread polyploid complex, the loss of self-incompatibility can be predicted by the cumulative effects of whole-genome duplication and intercontinental dispersal., (© 2018 Botanical Society of America.)

Whole genome duplication is considered to be a significant contributor to angiosperm speciation due to accumulation of rapid, strong interploid reproductive isolation. However, recent work suggests that interploid reproductive isolation may not be complete, especially among higher order cytotypes. This study evaluates postzygotic reproductive isolation among three cytotypes within a polyploid complex. We conducted reciprocal crosses using two diploid and two hexaploid populations each crossed to tetraploid populations spanning the geographic and phylogenetic range of the Campanula rotundifolia polyploid complex. Interploid and intrapopulation crosses were scored for fruit set, seed number, germination proportion and pollen viability. Postzygotic isolation was calculated for each cross as the product of these fitness components. A subset of offspring was cytotyped via flow cytometry. Postzygotic isolation was significantly lower in tetraploid-hexaploid crosses than diploid-tetraploid crosses, mostly due to substantially higher germination among tetraploid-hexaploid crosses. Tetraploid-hexaploid crosses produced pentaploids exclusively, whereas diploid-tetraploid crosses produced both triploids and tetraploids in high frequencies. Postzygotic isolation was weaker among higher order polyploids than between diploids and tetraploids, and unreduced gametes may facilitate diploid-tetraploid reproduction. This incomplete postzygotic isolation could allow ongoing interploid gene flow, especially among higher order polyploids, which may slow divergence and speciation in polyploid complexes., (© 2016 The Authors. New Phytologist © 2016 New Phytologist Trust.)

Aim: To compare vasoconstriction of the auricular artery and characteristics of blood flow in the carotid arteries between lambs grazing perennial ryegrass that was either infected with the AR6 novel endophyte (AR6), wild-type endophyte or endophyte-free., Methods: Sixteen Coopworth lambs, mean 23.7 (SD 1.8) kg, were randomly assigned to graze three, 0.10-ha pastures of perennial ryegrass (cultivar Extreme) located in Lincoln, New Zealand, that were infected with either the AR6 novel endophyte (n=5) or wild-type endophyte (n=6) or were endophyte-free (n=5), for 18 days until 16 March 2009. Lambs on AR6 pasture were then switched to endophyte-free pasture, and those on endophyte-free were switched to AR6 pasture, for 18 days. Lambs continued grazing the wild-type ryegrass during both phases of the study. Colour Doppler ultrasonography was used to monitor cross-sectional area of lumina in the auricular and carotid arteries as measurements of vasoconstriction, and to measure pulsatility indices, heart rate, systolic and diastolic velocities, and mean velocity in the carotid artery. Urine was sampled once during each phase, to measure the concentration of urinary alkaloids. A heat challenge (32°C) was imposed on the last day of the experiment, to determine treatment effects on rectal temperature and respiration rate., Results: Vasoconstriction was detected in the auricular arteries of lambs grazing AR6 and wild-type pastures. Areas of lumina declined linearly over 9 days in lambs that were switched from endophyte-free to AR6 pastures (p<0.05), and areas increased linearly in lambs that were switched from AR6 to endophyte-free pasture (p<0.001). Resistance to blood flow in the carotid arteries decreased linearly in the 9 days after lambs were switched from AR6 to endophyte-free pasture(p<0.05), and tended to increase after lambs on endophyte-free pasture were switched to AR6 (p<0.10). The concentrations of urinary alkaloids decreased after switching lambs from AR6 to endophyte-free pasture, and increased after switching from endophyte-free to AR6 pasture (p<0.05). The concentrations of urinary alkaloids of lambs on wild-type pasture were similar between the conditioning and experimental phases. There were no treatment effects on rectal temperature and respiration rate during the heat challenge., Conclusions: These results indicated that management approaches are needed to overcome potential vulnerabilities to heat stress for sheep grazing AR6 perennial ryegrass. Furthermore, following grazing such pasture, lambs will need to graze endophyte-free ryegrass for >18 days, to completely clear ergot alkaloids from their vasculature, assuming that complete clearance can be achieved.

White clover (Trifolium repens) is naturally polymorphic for cyanogenesis (hydrogen cyanide release following tissue damage). The ecological factors favouring cyanogenic and acyanogenic plants have been examined in numerous studies over the last half century, making this one of the best-documented examples of an adaptive polymorphism in plants. White clover cyanogenesis is controlled by two, independently segregating Mendelian genes: Ac/ac controls the presence/absence of cyanogenic glucosides; and Li/li controls the presence/absence of their hydrolysing enzyme, linamarase. In this study, we examine the molecular evolution and population genetics of Li as it relates to the cyanogenesis polymorphism. We report here that Li exists as a single-copy gene in plants possessing linamarase activity, and that the absence of enzyme activity in li/li plants is correlated with the absence of much or all of the gene from the white clover genome. Consistent with this finding, we confirm by reverse transcription-polymerase chain reaction that Li gene expression is absent in plants lacking enzyme activity. In a molecular population genetic analysis of Li and three unlinked genes using a worldwide sample of clover plants, we find an absence of nucleotide variation and statistically significant deviations from neutrality at Li; these findings are consistent with recent positive directional selection at this cyanogenesis locus.