Interdependence of cellular and network properties in respiratory rhythm generation.

How breathing is generated by the preBötzinger complex (preBötC) remains divided between two ideological frameworks, and a persistent sodium current (INaP) lies at the heart of this debate. Although INaP is widely expressed, the pacemaker hypothesis considers it essential because it endows a small subset of neurons with intrinsic bursting or "pacemaker" activity. In contrast, burstlet theory considers INaP dispensable because rhythm emerges from "preinspiratory" spiking activity driven by feed-forward network interactions. Using computational modeling, we find that small changes in spike shape can dissociate INaP from intrinsic bursting. Consistent with many experimental benchmarks, conditional effects on spike shape during simulated changes in oxygenation, development, extracellular potassium, and temperature alter the prevalence of intrinsic bursting and preinspiratory spiking without altering the role of INaP. Our results support a unifying hypothesis where INaP and excitatory network interactions, but not intrinsic bursting or preinspiratory spiking, are critical interdependent features of preBötC rhythmogenesis.

Treatment modalities and survival outcomes in prostate cancer parenchymal brain metastasis.

BACKGROUND: Prostate cancer (PCa) parenchymal brain metastases are uncommon and troubling observations in the course of the disease. Our study aims to evaluate the prevalence of brain metastases among PCa patients while reporting various therapeutic modalities, clinical features, and oncological outcomes. METHODS: We retrospectively identified 34 patients with parenchymal brain metastasis out of 4575 patients using a prospectively maintained database that contains clinicopathologic characteristics of PCa patients between January 2012 and December 2021. Based on the three treatment modalities used, the patients were divided into three groups: stereotactic radiosurgery (SRS), whole brain radiotherapy (WBRT), and systemic therapy alone. The Kaplan-Meier curve was used to calculate overall survival [OS] probability and the Cox proportional hazards regression model was used to compare between groups. RESULTS: At the time of brain metastasis diagnosis, the median age was 66 years, the median (interquartile range [IQR]) prostate-specific antigen (PSA) was 2.2 (0.1-26.6) ng/ml and the median (IQR) months from initial PCa diagnosis to brain metastasis development was 70.8 (27.6-100.9). The median (IQR) primary Gleason score was 8 (7-9) and over a median (IQR) follow-up time of 2.2 (1.2-16.5) months, 76.5% (n = 26) of the patients died. Thirteen (38.2%) patients had solitary lesion, whereas 21 (61.8%) had ≥2 lesions. The lesions were supratentorial in 19 (55.9%) patients, infratentorial in six (17.6%), and both sides in nine (26.5%). Among all 34 patients, 10 (29.4%) were treated with SRS, seven (20.6%) with WBRT, and 17 (50%) with systemic therapy alone. OS varied greatly between the three treatment modalities (log-rank test, p = 0.049). Those who were treated with SRS and WBRT had better OS compared with patients who were treated with systemic therapy alone (hazard ratio: 0.37, 95% confidence interval: 0.16-0.86, p = 0.022). CONCLUSIONS: In our single-institutional study, we confirmed that PCa brain metastasis is associated with poor survival outcomes and more advanced metastatic disease. Furthermore, we found that SRS and WBRT for brain metastasis in patients with recurrent PCa appear to be associated with improved OS as compared with systemic therapy alone and are likely secondary to selection bias.

Sexual attraction with pollination during feeding behaviour: implications for transitions between specialized strategies.

BACKGROUND AND AIMS: Understanding the origin of pollination by sexual deception has proven challenging, as sexually deceptive flowers are often highly modified, making it hard to resolve how any intermediate forms between sexual deception and an ancestral strategy might have functioned. Here, we report the discovery in Caladenia (Orchidaceae) of sexual attraction with pollination during feeding behaviour, which may offer important clues for understanding shifts in pollination strategy. METHODS: For Caladenia robinsonii, we observed the behaviour of its male wasp pollinator, Phymatothynnus aff. nitidus (Thynnidae), determined the site of release of the sexual attractant, and experimentally evaluated if the position of the attractant influences rates of attempted copulation and feeding behaviour. We applied GC-MS to test for surface sugar on the labellum. To establish if this pollination strategy is widespread in Caladenia, we conducted similar observations and experiments for four other Caladenia species. KEY RESULTS: In C. robinsonii, long-range sexual attraction of the pollinator is via semiochemicals emitted from the glandular sepal tips. Of the wasps landing on the flower, 57 % attempted copulation with the sepal tips, while 27 % attempted to feed from the base of the labellum, the behaviour associated with pollen transfer. A similar proportion of wasps exhibited feeding behaviour when the site of odour release was manipulated. A comparable pollination strategy occurs in another phylogenetically distinct clade of Caladenia. CONCLUSIONS: We document a previously overlooked type of sexual deception for orchids involving long-distance sexual attraction, but with pollination occurring during feeding behaviour at the labellum. We show this type of sexual deception operates in other Caladenia species and predict that it is widespread across the genus. Our findings may offer clues about how an intermediate transitional strategy from a food-rewarding or food-deceptive ancestor operated during the evolution of sexual deception.

A novel mechanism for ramping bursts based on slow negative feedback in model respiratory neurons.

Recordings from pre-Bötzinger complex neurons responsible for the inspiratory phase of the respiratory rhythm reveal a ramping burst pattern, starting around the time that the transition from expiration to inspiration begins, in which the spike rate gradually rises until a transition into a high-frequency burst occurs. The spike rate increase along the burst is accompanied by a gradual depolarization of the plateau potential that underlies the spikes. These effects may be functionally important for inducing the onset of inspiration and hence maintaining effective respiration; however, most mathematical models for inspiratory bursting do not capture this activity pattern. Here, we study how the modulation of spike height and afterhyperpolarization via the slow inactivation of an inward current can support various activity patterns including ramping bursts. We use dynamical systems methods designed for multiple timescale systems, such as bifurcation analysis based on timescale decomposition and averaging over fast oscillations, to generate an understanding of and predictions about the specific dynamic effects that lead to ramping bursts. We also analyze how transitions between ramping and other activity patterns may occur with parameter changes, which could be associated with experimental manipulations, environmental conditions, and/or development.

Effect of Routine Child Physical Abuse Screening Tool on Emergency Department Efficiency.

OBJECTIVES: Physical abuse is a significant cause of morbidity and mortality for children. Routine screening by emergency nurses has been proposed to improve recognition, but the effect on emergency department (ED) workflow has not yet been assessed. We sought to evaluate the feasibility of routine screening and its effect on length of stay in a network of general EDs. METHODS: A 2-question child physical abuse screening tool was deployed for children <6 years old who presented for care in a system of 27 general EDs. Data were compared for the 6 months before and after screening was deployed (4/1/2019-10/2/2019 vs 10/3/2019-3/31/2020). The main outcome was ED length of stay in minutes. RESULTS: There were 14,133 eligible visits in the prescreening period and 16,993 in the screening period. Screening was completed for 13,404 visits (78.9%), with 116 (0.7%) screening positive. The mean ED length of stay was not significantly different in the prescreening (95.9 minutes) and screening periods (95.2 minutes; difference, 0.7 minutes; 95% CI, -1.5, 2.8). Among those who screened positive, 29% were reported to child protective services. On multivariable analysis, implementation of the screening tool did not impact overall ED length of stay. There were no significant differences in resource utilization between the prescreening and screening periods. CONCLUSIONS: Routine screening identifies children at high risk of physical abuse without increasing ED length of stay or resource utilization. Next steps will include determining rates of subsequent serious physical abuse in children with or without routine screening.

Strong phylogenetic congruence between Tulasnella fungi and their associated Drakaeinae orchids.

The study of congruency between phylogenies of interacting species can provide a powerful approach for understanding the evolutionary history of symbiotic associations. Orchid mycorrhizal fungi can survive independently of orchids making cospeciation unlikely, leading us to predict that any congruence would arise from host-switches to closely related fungal species. The Australasian orchid subtribe Drakaeinae is an iconic group of sexually deceptive orchids that consists of approximately 66 species. In this study, we investigated the evolutionary relationships between representatives of all six Drakaeinae orchid genera (39 species) and their mycorrhizal fungi. We used an exome capture dataset to generate the first well-resolved phylogeny of the Drakaeinae genera. A total of 10 closely related Tulasnella Operational Taxonomic Units (OTUs) and previously described species were associated with the Drakaeinae orchids. Three of them were shared among orchid genera, with each genus associating with 1-6 Tulasnella lineages. Cophylogenetic analyses show Drakaeinae orchids and their Tulasnella associates exhibit significant congruence (p < 0.001) in the topology of their phylogenetic trees. An event-based method also revealed significant congruence in Drakaeinae-Tulasnella relationships, with duplications (35), losses (25), and failure to diverge (9) the most frequent events, with minimal evidence for cospeciation (1) and host-switches (2). The high number of duplications suggests that the orchids speciate independently from the fungi, and the fungal species association of the ancestral orchid species is typically maintained in the daughter species. For the Drakaeinae-Tulasnella interaction, a pattern of phylogenetic niche conservatism rather than coevolution likely explains the observed phylogenetic congruency in orchid and fungal phylogenies. Given that many orchid genera are characterized by sharing of fungal species between closely related orchid species, we predict that these findings may apply to a wide range of orchid lineages.

An outbreak of Salmonella Typhimurium associated with the consumption of raw liver at an Eid al-Adha celebration in Wales (UK), July 2021.

In July 2021, Public Health Wales received two notifications of salmonella gastroenteritis. Both cases has attended the same barbecue to celebrate Eid al-Adha, two days earlier. Additional cases attending the same barbecue were found and an outbreak investigation was initiated. The barbecue was attended by a North African community's social network. On same day, smaller lunches were held in three homes in the social network. Many people attended both a lunch and the barbecue. Cases were defined as someone with an epidemiological link to the barbecue and/or lunches with diarrhoea and/or vomiting with date of onset following these events. We undertook a cohort study of 36 people attending the barbecue and/or lunch, and a nested case-control study using Firth logistic regression. A communication campaign, sensitive towards different cultural practices, was developed in collaboration with the affected community. Consumption of a traditional raw liver dish, 'marrara', at the barbecue was the likely vehicle for infection (Firth logistic regression, aOR: 49.99, 95%CI 1.71-1461.54, p = 0.02). Meat and offal came from two local butchers (same supplier) and samples yielded identical whole genome sequences as cases. Future outbreak investigations should be relevant to the community affected by considering dishes beyond those found in routine questionnaires.

Third-trimester percentage predicted lung volume and percentage liver herniation as prognostic indicators in congenital diaphragmatic hernia.

BACKGROUND: Over the last two decades, fetal imaging has greatly improved, and new prenatal imaging measurements have been developed to characterize congenital diaphragmatic hernia (CDH) severity. OBJECTIVE: To determine the best prenatal imaging predictor of postnatal CDH outcomes, including use of extracorporeal membrane oxygenation (ECMO) and in-hospital mortality, with particular attention to the percentage of liver herniation (%LH) as a predictor. Additionally, we sought to guide best practices across hospital systems including improved models of prenatal risk assessment. MATERIALS AND METHODS: We conducted a retrospective review of infants with left CDH who were prenatally diagnosed. We analyzed prenatal imaging measurements including observed-to-expected (O/E) lung-to-head ratio (LHR) on US, percentage predicted lung volume (PPLV) on MRI, and O/E total fetal lung volume (TFLV) and %LH on MRI. We compared prenatal imaging characteristics for infants with (1) in-hospital postnatal mortality and (2) use of ECMO. Then we performed multivariate logistic regression to determine independent predictors of postnatal outcomes. RESULTS: We included 63 infants with a median gestation of 34 weeks at the time of prenatal MRI. Low O/E LHR (31.2 vs. 50, P < 0.0001), PPLV (14.7 vs. 22.6, P < 0.0001) and O/E TLFV (24.6 vs. 38.3, P < 0.0001) and high %LH (15.1 vs. 2.1, P = 0.0006) were associated with worse postnatal outcomes; however, only PPLV was predictive of survival and need for ECMO on multivariable analysis. PPLV survival to discharge model showed an area under the curve (AUC) of 0.93 (95% confidence interval [CI]: 0.86, 0.99), P < 0.0001; and an odds ratio of 68.7 (95% CI: 6.5-2,302), P = 0.003. PPLV need for ECMO model showed AUC = 0.87 (95% CI: 0.78, 0.96), P < 0.0001; and odds ratio = 20.1 (95% CI: 3.1-226.3), P = 0.011. CONCLUSION: Low O/E LHR, PPLV and O/E TFLV and high %LH in the third trimester are associated with worse postnatal outcomes. PPLV most strongly predicted outcome using a logistic regression model. Percentage of liver herniation was not an independent predictor of outcomes.

Inspiratory rhythm generation is stabilized by Ih.

Cellular and network properties must be capable of generating rhythmic activity that is both flexible and stable. This is particularly important for breathing, a rhythmic behavior that dynamically adapts to environmental, behavioral, and metabolic changes from the first to the last breath. The pre-Bötzinger complex (preBötC), located within the ventral medulla, is responsible for producing rhythmic inspiration. Its cellular properties must be tunable, flexible as well as stabilizing. Here, we explore the role of the hyperpolarization-activated, nonselective cation current (Ih) for stabilizing PreBötC activity during opioid exposure and reduced excitatory synaptic transmission. Introducing Ih into an in silico preBötC network predicts that loss of this depolarizing current should significantly slow the inspiratory rhythm. By contrast, in vitro and in vivo experiments revealed that the loss of Ih minimally affected breathing frequency, but destabilized rhythmogenesis through the generation of incompletely synchronized bursts (burstlets). Associated with the loss of Ih was an increased susceptibility of breathing to opioid-induced respiratory depression or weakened excitatory synaptic interactions, a paradoxical depolarization at the cellular level, and the suppression of tonic spiking. Tonic spiking activity is generated by nonrhythmic excitatory and inhibitory preBötC neurons, of which a large percentage express Ih. Together, our results suggest that Ih is important for maintaining tonic spiking, stabilizing inspiratory rhythmogenesis, and protecting breathing against perturbations or changes in network state.NEW & NOTEWORTHY The Ih current plays multiple roles within the preBötC. This current is important for promoting intrinsic tonic spiking activity in excitatory and inhibitory neurons and for preserving rhythmic function during conditions that dampen network excitability, such as in the context of opioid-induced respiratory depression. We therefore propose that the Ih current expands the dynamic range of rhythmogenesis, buffers the preBötC against network perturbations, and stabilizes rhythmogenesis by preventing the generation of unsynchronized bursts.

Cost effectiveness of treatment strategies for high risk prostate cancer.

BACKGROUND: Patients with high-risk prostate cancer (HRPC) have multiple accepted treatment options. Because there is no overall survival benefit of one option over another, appropriate treatment must consider patient life expectancy, quality of life, and cost. METHODS: The authors compared quality-adjusted life years (QALYs) and cost effectiveness among treatment options for HRPC using a Markov model with three treatment arms: (1) external-beam radiotherapy (EBRT) delivered with 20 fractions, (2) EBRT with 23 fractions followed by low-dose-rate (LDR) brachytherapy boost, or (3) radical prostatectomy alone. An exploratory analysis considered a simultaneous integrated boost according to the FLAME trial (ClinicalTrials.gov identifier NCT01168479). RESULTS: Treatment strategies were compared using the incremental cost-effectiveness ratio (ICER). EBRT with LDR brachytherapy boost was a cost-effective strategy (ICER, $20,929 per QALY gained). These results were most sensitive to variations in the biochemical failure rate. However, the results still demonstrated cost effectiveness for the brachytherapy boost paradigm, regardless of any tested parameter ranges. Probabilistic sensitivity analysis demonstrated that EBRT with LDR brachytherapy was favored in 52% of 100,000 Monte Carlo iterations. In an exploratory analysis, EBRT with a simultaneous integrated boost was also a cost-effective strategy, resulting in an ICER of $62,607 per QALY gained; however, it was not cost effective compared with EBRT plus LDR brachytherapy boost. CONCLUSIONS: EBRT with LDR brachytherapy boost may be a cost-effective treatment strategy compared with EBRT alone and radical prostatectomy for HRPC, demonstrating high-value care. The current analysis suggests that a reduction in biochemical failure alone can result in cost-effective care, despite no change in overall survival.

Metastasis-directed Therapy Without Androgen Deprivation Therapy in Solitary Oligorecurrent Prostate Cancer.

PURPOSE: As controversy remains regarding the role of metastasis-directed therapy in patients with oligometastatic prostate cancer, we sought to characterize outcomes of metastasis-directed therapy without concomitant androgen deprivation therapy in the specific subset of patients with a solitary metastatic lesion on C-11 choline positron emission tomography imaging whose primary tumor has already been treated. MATERIALS AND METHODS: We identified 124 consecutive prostate cancer patients from 2008 to 2018 with a solitary oligorecurrent metastatic lesion on positron emission tomography imaging who were treated with metastasis-directed therapy without androgen deprivation therapy from the Mayo Clinic C-11 choline registry. Metastasis-directed therapy consisted of either stereotactic body radiation therapy or surgical excision. RESULTS: Of these 124 patients, 67 were treated with surgery (median follow-up 54 months) and 57 patients were treated with stereotactic body radiation therapy (median follow-up 53 months). Of patients treated with surgery, 80.5% had >50% decline in prostate specific antigen at first follow-up, and the 3-year radiographic progression-free survival was 29%. Median time to initiation of systemic therapy in this cohort was 18.5 months (interquartile range 8.4-44.7 months). Meanwhile, for patients treated with stereotactic body radiation therapy, 40.3% had >50% decline in prostate specific antigen at first follow-up, and the 3-year radiographic progression-free survival was 17%. Similarly, median time to initiation of systemic therapy was 17.8 months (interquartile range 7.1-42.3 months). CONCLUSIONS: This study represents the first reported series of metastasis-directed therapy without androgen deprivation therapy in patients with solitary oligorecurrent metastatic prostate cancer. These results suggest that metastasis-directed therapy without androgen deprivation therapy can delay initiation of systemic therapy and highlight the need for further prospective study for select patients with solitary metastatic recurrences of prostate cancer.

Dynamics of ramping bursts in a respiratory neuron model.

Intensive computational and theoretical work has led to the development of multiple mathematical models for bursting in respiratory neurons in the pre-Bötzinger Complex (pre-BötC) of the mammalian brainstem. Nonetheless, these previous models have not captured the pre-inspiratory ramping aspects of these neurons' activity patterns, in which relatively slow tonic spiking gradually progresses to faster spiking and a full-blown burst, with a corresponding gradual development of an underlying plateau potential. In this work, we show that the incorporation of the dynamics of the extracellular potassium ion concentration into an existing model for pre-BötC neuron bursting, along with some parameter adjustments, suffices to induce this ramping behavior. Using fast-slow decomposition, we show that this activity can be considered as a form of parabolic bursting, but with burst termination at a homoclinic bifurcation rather than as a SNIC bifurcation. We also investigate the parameter-dependence of these solutions and show that the proposed model yields a greater dynamic range of burst frequencies, durations, and duty cycles than those produced by other models in the literature.

Discreet Values of Shock Index Pediatric Age-Adjusted (SIPA) to Predict Intervention in Children With Blunt Organ Injuries.

INTRODUCTION: Elevated shock index pediatric age-adjusted (SIPA) has been shown to be associated with the need for both blood transfusion and intervention in pediatric patients with blunt liver and spleen injuries (BLSI). SIPA has traditionally been used as a binary value, which can be classified as elevated or normal, and this study aimed to assess if discreet values above SIPA cutoffs are associated with an increased probability of blood transfusion and failure of nonoperative management (NOM) in bluntly injured children. MATERIALS AND METHODS: Children aged 1-18 y with any BLSI admitted to a Level-1 pediatric trauma center between 2009 and 2020 were analyzed. Blood transfusion was defined as any transfusion within 24 h of arrival, and failure of NOM was defined as any abdominal operation or angioembolization procedure for hemorrhage control. The probabilities of receiving a blood transfusion or failure of NOM were calculated at different increments of 0.1. RESULTS: There were 493 patients included in the analysis. The odds of requiring blood transfusion increased by 1.67 (95% CI 1.49, 1.90) for each 0.1 unit increase of SIPA (P < 0.001). A similar trend was seen initially for the probability of failure of nonoperative management, but beyond a threshold, increasing values were not associated with failure of NOM. On subanalysis excluding patients with a head injury, increased 0.1 increments were associated with increased odds for both interventions. CONCLUSIONS: Discreet values above age-related SIPA cutoffs are correlated with higher probabilities of blood transfusion in pediatric patients with BLSI and failure of NOM in those without head injury. The use of discreet values may provide clinicians with more granular information about which patients require increased resources upon presentation.

Adolescent Vaping-Associated Trauma in the Western United States.

INTRODUCTION: Electronic cigarettes (e-cigarettes) are handheld, battery-powered vaporizing devices. It is estimated that more than 25% of youth have used these devices recreationally. While vaping-associated lung injury is an increasingly recognized risk, little is known about the risk of traumatic injuries associated with e-cigarette malfunction. METHODS: A multi-institutional retrospective study was performed by querying the electronic health records at nine children's hospitals. Patients who sustained traumatic injuries while vaping from January 2016 through December 2019 were identified. Patient demographics, injury characteristics, and the details of trauma management were reviewed. RESULTS: 15 children sustained traumatic injuries due to e-cigarette explosion. The median age was 17 y (range 13-18). The median injury severity score was 2 (range 1-5). Three patients reported that their injury coincided with their first vaping experience. Ten patients required hospital admission, three of whom required intensive care unit admission. Admitted patients had a median length of stay of 3 d (range 1-6). The injuries sustained were: facial burns (6), loss of multiple teeth (5), thigh and groin burns (5), hand burns (4), ocular burns (4), a radial nerve injury, a facial laceration, and a mandible fracture. Six children required operative intervention, one of whom required multiple operations for a severe hand injury. CONCLUSIONS: In addition to vaping-associated lung injury, vaping-associated traumatic injuries are an emerging and worrisome injury pattern sustained by adolescents in the United States. This report highlights another means by which e-cigarettes pose an increasing risk to a vulnerable youth population.

To give or not to give? Blood for pediatric trauma patients prior to pediatric trauma center arrival.

PURPOSE: This study evaluates the indications, safety and clinical outcomes associated with the administration of blood products prior to arrival at a pediatric trauma center (prePTC). METHODS: Children (≤ 18 years) who were highest level activations at an ACS level 1 pediatric trauma center (PTC) from 2009-2019 were divided into groups:(1) patients with transport times < 4 h who received blood prePTC(preBlood) versus (2) age matched controls with transport times < 4 h who only received crystalloid prePTC (preCrystalloid). RESULTS: Of 1269 trauma activations, 38 met preBlood and 38 met preCrystalloid inclusion criteria. A similar volume of prePTC crystalloid infusion was observed between cohorts (p = 0.311). PreBlood patients evidenced greater hemodynamic instability as demonstrated by higher prePTC pediatric age-adjusted shock index (SIPA) scores. PreBlood patients showed improvement in lactate (p = 0.038) and hemoglobin (p = 0.041) levels upon PTC arrival. PreBlood patients received less crystalloid within 12 h of PTC admission (p = 0.017). No significant differences were found in blood transfusion volumes within six (p = 0.293) and twenty-four (p = 0.575) hours of admission, nor in mortality between cohorts (p = 0.091). CONCLUSIONS: The administration of blood to pediatric trauma patients prior to arrival at a PTC is safe, transiently improves markers of shock, and was not associated with worse outcomes.

Continental-scale distribution and diversity of Ceratobasidium orchid mycorrhizal fungi in Australia.

BACKGROUND AND AIMS: Mycorrhizal fungi are a critical component of the ecological niche of most plants and can potentially constrain their geographical range. Unlike other types of mycorrhizal fungi, the distributions of orchid mycorrhizal fungi (OMF) at large spatial scales are not well understood. Here, we investigate the distribution and diversity of Ceratobasidium OMF in orchids and soils across the Australian continent. METHODS: We sampled 217 Ceratobasidium isolates from 111 orchid species across southern Australia and combined these with 311 Ceratobasidium sequences from GenBank. To estimate the taxonomic diversity of Ceratobasidium associating with orchids, phylogenetic analysis of the ITS sequence locus was undertaken. Sequence data from the continent-wide Australian Microbiome Initiative were used to determine the geographical range of operational taxonomic units (OTUs) detected in orchids, with the distribution and climatic correlates of the two most frequently detected OTUs modelled using MaxEnt. KEY RESULTS: We identified 23 Ceratobasidium OTUs associating with Australian orchids, primarily from the orchid genera Pterostylis, Prasophyllum, Rhizanthella and Sarcochilus. OTUs isolated from orchids were closely related to, but distinct from, known pathogenic fungi. Data from soils and orchids revealed that ten of these OTUs occur on both east and west sides of the continent, while 13 OTUs were recorded at three locations or fewer. MaxEnt models suggested that the distributions of two widespread OTUs are correlated with temperature and soil moisture of the wettest quarter and far exceeded the distributions of their host orchid species. CONCLUSIONS: Ceratobasidium OMF with cross-continental distributions are common in Australian soils and frequently have geographical ranges that exceed that of their host orchid species, suggesting these fungi are not limiting the distributions of their host orchids at large spatial scales. Most OTUs were distributed within southern Australia, although several OTUs had distributions extending into central and northern parts of the continent, illustrating their tolerance of an extraordinarily wide range of environmental conditions.

Oligometastatic prostatic cancer recurrence: role of salvage lymph node dissection (sLND) and radiation therapy-stereotactic body radiation therapy (RT-SBRT).

PURPOSE OF REVIEW: Metastases directed therapy (MDT) is an increasingly utilized modality in patients with oligometastatic prostate cancer (OMPC) recurrence. The purpose of our review is to discuss the recent literature on the safety and oncologic outcomes of this treatment approach. RECENT FINDINGS: Metastases directed therapy, in particular, stereotactic body radiation therapy (SBRT) and salvage lymph node dissection (sLND), has shown promising efficacy in patients with OMPC. Many case series report favorable outcomes with MDT as compared to hormonal deprivation therapy alone or surveillance. Of the few case series investigating the use of MDT as part of a multimodality approach in castrate-resistant OMPC, more favorable outcomes in comparison to the use of systemic treatment alone are reported. SUMMARY: With the recent advances in imaging techniques, particularly molecular imaging, management of OMPC has progressed rapidly in the last few years. The feasibility and benefits of MDT in OMPC have been demonstrated in prospective and retrospective series. Further prospective studies investigating the role of MDT to define optimal patient subgroups and management strategies are warranted.

Gastrostomy Button Placement in Infants With Cyanotic Versus Acyanotic Congenital Heart Disease.

BACKGROUND: Infants with congenital heart disease (CHD) may exhibit increased metabolic demands, and many will undergo placement of a gastrostomy to achieve adequate nutritional intake. There is a paucity of data, however, comparing the operative risks and overall complications of gastrostomy placement in cyanotic versus acyanotic infants with CHD. We hypothesized that patients with cyanotic CHD would have a higher rate of gastrostomy-associated complications than infants with acyanotic CHD. METHODS: We retrospectively reviewed patients who underwent gastrostomy button placement after cardiac surgery for CHD between 2013 and 2018. Patients were stratified into cyanotic CHD and acyanotic CHD cohorts. Patient data were extracted from the Society of Thoracic Surgeons database and merged with clinical data related to gastrostomy placement and complications from chart review. Unadjusted analyses were used to find covariates associated with cyanotic CHD and acyanotic CHD, using a t-test or Wilcoxon rank-sum test for continuous data, depending on normalcy, and χ2 or Fisher's exact tests for categorical data depending on the distribution. RESULTS: There were 257 infants with CHD who underwent gastrostomy placement during the study period, of which 86 had cyanotic CHD. There were no significant differences in baseline weight or preoperative albumin levels between the two groups. Patients with cyanotic CHD had a lower incidence of comorbid syndromes (P = 0.0001), higher Society of Thoracic Surgeons-European Association for Cardio-Thoracic Surgery scores (P < 0.0001), and higher postoperative mortality rate (P = 0.0189). There was a higher rate of granulation tissue formation in patients with acyanotic CHD (48.5% versus 22.1%, P < 0.0001). There were no differences in other gastrostomy button-related complications, including leakage, wound infection, or dislodgement. CONCLUSIONS: Patients with acyanotic CHD demonstrated a higher incidence of granulation tissue. We found no difference in gastrostomy-specific complication rates between the two groups, with the notable exception of granulation tissue formation. Based on this study, the diagnosis of cyanotic CHD does not increase the risk of gastrostomy-related complications.

Unexpectedly low paternal diversity is associated with infrequent pollinator visitation for a bird-pollinated plant.

The behaviour of pollinators has important consequences for plant mating. Nectar-feeding birds often display behaviour that results in more pollen carryover than insect pollinators, which is predicted to result in frequent outcrossing and high paternal diversity for bird-pollinated plants. We tested this prediction by quantifying mating system parameters and bird visitation in three populations of an understory bird-pollinated herb, Anigozanthos humilis (Haemodoraceae). Microsatellite markers were used to genotype 131 adult plants, and 211 seeds from 23 maternal plants, from three populations. While outcrossing rates were high, estimates of paternal diversity were surprisingly low compared with other bird-pollinated plants. Despite nectar-feeding birds being common at the study sites, visits to A. humilis flowers were infrequent (62 visits over 21,552 recording hours from motion-triggered cameras, or equivalent to one visit per flower every 10 days), and the majority (76%) were by a single species, the western spinebill Acanthorhynchus superciliosus (Meliphagidae). Pollen counts from 30 captured honeyeaters revealed that A. humilis comprised just 0.3% of the total pollen load. For 10 western spinebills, A. humilis pollen comprised only 4.1% of the pollen load, which equated to an average of 3.9 A. humilis pollen grains per bird. Taken together, our findings suggest that low visitation rates and low pollen loads of floral visitors have led to the low paternal diversity observed in this understory bird-pollinated herb. As such, we shed new light on the conditions that can lead to departures from high paternal diversity for plants competing for the pollination services of generalist nectar-feeding birds.

A pediatric surgeon's dilemma: does cholecystectomy improve symptoms of biliary dyskinesia?

BACKGROUND: Biliary dyskinesia (BD) is a well-established gallbladder pathology in adult patients and rates of cholecystectomy for BD continue to rise in the United States. Many pediatric patients with vague abdominal pain of variable duration are evaluated for biliary dyskinesia. It remains unknown which cohort of pediatric patients diagnosed with BD are most likely to have sustained improvement in symptoms following laparoscopic cholecystectomy. We aimed to determine whether cholecystectomy resulted in symptom relief and led to a reduction in the number of medical visits related to gastrointestinal (GI) symptoms after surgery. METHODS: We performed a multi-institution retrospective review of all children < 18 years of age who underwent laparoscopic cholecystectomy for BD between January 2013 and April 2018 in our hospital system. GI symptoms and clinical visits related to a GI complaint were assessed preoperatively. Patients were followed for 2 years after surgery. At 6 months and 2 years postoperatively, symptoms and the rate of medical visits related to a GI complaint were quantified and compared to the preoperative values. RESULTS: In total, 45 patients met our inclusion criteria. Of these, 82% of patients were female. The average age was 14 years old (± 2.6) and 56% of patients met the criteria for being overweight or obese. The mean gallbladder ejection fraction was 13% (± 10.8). All patients had abdominal pain, 82% (37/45) presented with nausea, and 51% (23/45) presented with post-prandial pain. Six months postoperatively, 58% of patients experienced resolution of their abdominal pain which decreased to 38% of patients after 2 years. Similarly, 59% had resolution of their nausea at 6 months compared to 43% at 2 years, and 100% had resolution of their post-prandial pain at 6 months compared to 91% at 2 years. The total number of clinical visits related to a GI complaint decreased from 2.6 (± 2.4) preoperatively to 1.0 (± 1.3) within 6 months postoperatively. When followed to 2 years postoperatively, the 6-month rate of clinical visits related to a GI complaint decreased from a mean of 2.6 preoperatively to 0.71 following surgery. CONCLUSIONS: Following cholecystectomy, we observed a high percentage of durable symptom resolution in those patients with BD who presented with post-prandial pain. Patients with non-food-related abdominal pain, with or without nausea and vomiting, had a lower rate of symptom resolution after surgery and the rate declined with time. For patients without post-prandial pain, evaluation and treatment of alternative sources of pain should be considered prior to surgery. Regardless of their presenting symptoms, patients who underwent surgery for BD had fewer clinical GI-related visits after surgery. However, no specific gallbladder ejection fraction or symptom alone was predictive of a lower rate of clinical visits postoperatively.