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Cantú Syndrome (CS) is an autosomal dominant disorder caused by gain-of-function (GoF) mutations in the Kir6.1 and SUR2 subunits of KATP channels. KATP overactivity results in a chronic reduction in arterial tone and hypotension, leading to other systemic cardiovascular complications. However, the underlying mechanism of lymphedema, developed by >50% of CS patients, is unknown. We investigated whether lymphatic contractile dysfunction occurs in mice expressing CS mutations in Kir6.1 (Kir6.1[V65M]) or SUR2 (SUR2[A478V], SUR2[R1154Q]). Pressure myograph tests of contractile function of popliteal lymphatic vessels over the physiological pressure range revealed significantly impaired contractile strength and reduced frequency of spontaneous contractions at all pressures in heterozygous Kir6.1[V65M] vessels, compared to control littermates. Contractile dysfunction of intact popliteal lymphatics in vivo was confirmed using near-infrared fluorescence microscopy. Homozygous SUR2[A478V] vessels exhibited profound contractile dysfunction ex vivo, but heterozygous SUR2[A478V] vessels showed essentially normal contractile function. However, further investigation of vessels from all three GoF mouse strains revealed significant disruption in contraction wave entrainment, decreased conduction speed and distance, multiple pacemaker sites, and reversing wave direction. Tests of 2-valve lymphatic vessels forced to pump against an adverse pressure gradient revealed that all CS-associated genotypes were essentially incapable of pumping under an imposed outflow load. Our results show that varying degrees of lymphatic contractile dysfunction occur in proportion to the degree of molecular GoF in Kir6.1 or SUR2. This is the first example of lymphatic contractile dysfunction caused by a smooth muscle ion channel mutation and potentially explains the susceptibility of CS patients to lymphedema.

The severe acute respiratory syndrome coronavirus (SARS‐Cov‐2) resulting in the coronavirus disease 2019 (COVID‐19) is documented to have a negative psychosocial impact on patients. Home dialysis patients may be at risk of additional isolating factors affecting their mental health. The aim of this study is to describe levels of anxiety and quality of life during the COVID‐19 pandemic among home dialysis patients. This is a single‐centre survey of home dialysis patients in Toronto, Ontario. Surveys were sent to 98 home haemodialysis and 43 peritoneal dialysis patients. Validated instruments (Haemodialysis and Peritoneal Dialysis Treatment Satisfaction Questionnaire, Generalized Anxiety Disorder 7 Item [GAD7] Scale, Patient Health Questionnaire [PHQ‐9], Illness Intrusiveness Ratings Scale, Family APGAR Questionnaire and The Self Perceived Burden Scale) assessing well‐being were used. Forty of the 141 patients surveyed, participated in September 2020. The mean age was 53.1 ± 12.1 years, with 60% male, and 85% home haemodialysis, 80% of patients rated their satisfaction with dialysis at 8/10 or greater, 82% of respondents reported either “not at all” or “for several days” indicating frequency of anxiety and depressive symptoms, 79% said their illness minimally or moderately impacted their life, 76% of respondents were almost always satisfied with interactions with family members, 91% were never or sometimes worried about caregiver burden. Among our respondents, there was no indication of a negative psychosocial impact from the pandemic, despite the increased social isolation. Our data further supports the use of home dialysis as the optimal form of dialysis., SUMMARY AT A GLANCE This survey of home haemodialysis or peritoneal dialysis patients found no indication of a negative psychosocial impact from the COVID‐19 pandemic, despite the increased social isolation. Thus, patients who are able to practise dialysis at home and hence minimize infectious contacts do not experience high levels of psychosocial distress, adding to the paradigm of home dialysis as the optimal form of dialysis.

In 2019, a group of archivists participated in two conference sessions focused on impostor syndrome in the archives field. Though no comprehensive study on impostor syndrome has been undertaken in the archives profession, the authors listened to numerous stories of the phenomenon among audience members. This perspectives article considers the presence and impact of impostor syndrome in the archives field. The authors define the phenomenon, review literature on its influences in the information science profession, include stories of archives professionals working with impostor syndrome, and offer suggestions for working through impostor syndrome.

ImportanceOpioids can cause severe respiratory depression by suppressing feedback mechanisms that increase ventilation in response to hypercapnia. Following the addition of boxed warnings to benzodiazepine and opioid products about increased respiratory depression risk with simultaneous use, the US Food and Drug Administration evaluated whether other drugs that might be used in place of benzodiazepines may cause similar effects.ObjectiveTo study whether combining paroxetine or quetiapine with oxycodone, compared with oxycodone alone, decreases the ventilatory response to hypercapnia.Design, Setting, and ParticipantsRandomized, double-blind, crossover clinical trial at a clinical pharmacology unit (West Bend, Wisconsin) with 25 healthy participants from January 2021 through May 25, 2021.InterventionsOxycodone 10 mg on days 1 and 5 and the following in a randomized order for 5 days: paroxetine 40 mg daily, quetiapine twice daily (increasing daily doses from 100 mg to 400 mg), or placebo.Main Outcomes and MeasuresVentilation at end-tidal carbon dioxide of 55 mm Hg (hypercapnic ventilation) using rebreathing methodology assessed for paroxetine or quetiapine with oxycodone, compared with placebo and oxycodone, on days 1 and 5 (primary) and for paroxetine or quetiapine alone compared with placebo on day 4 (secondary).ResultsAmong 25 participants (median age, 35 years [IQR, 30-40 years]; 11 female [44%]), 19 (76%) completed the trial. The mean hypercapnic ventilation was significantly decreased with paroxetine plus oxycodone vs placebo plus oxycodone on day 1 (29.2 vs 34.1 L/min; mean difference [MD], −4.9 L/min [1-sided 97.5% CI, −∞ to −0.6]; P = .01) and day 5 (25.1 vs 35.3 L/min; MD, −10.2 L/min [1-sided 97.5% CI, –∞ to –6.3]; P P = .28) or on day 5 (34.7 vs 35.3 L/min; MD, −0.6 L/min [1-sided 97.5% CI, −∞ to 3.2]; P = .37). As a secondary outcome, mean hypercapnic ventilation was significantly decreased on day 4 with paroxetine alone vs placebo (32.4 vs 41.7 L/min; MD, −9.3 L/min [1-sided 97.5% CI, −∞ to −3.9]; P P = .67). No drug-related serious adverse events were reported.Conclusions and RelevanceIn this preliminary study involving healthy participants, paroxetine combined with oxycodone, compared with oxycodone alone, significantly decreased the ventilatory response to hypercapnia on days 1 and 5, whereas quetiapine combined with oxycodone did not cause such an effect. Additional investigation is needed to characterize the effects after longer-term treatment and to determine the clinical relevance of these findings.Trial RegistrationClinicalTrials.gov Identifier: NCT04310579

Human cardiac-derived c-kit+ stromal cells (CSCs) have demonstrated efficacy in preclinical trials for the treatment of heart failure and myocardial dysfunction. Unfortunately, large variability in patient outcomes and cell populations remains a problem. Previous research has demonstrated that the reparative capacity of CSCs may be linked to the age of the cells: CSCs derived from neonate patients increase cardiac function and reduce fibrosis. However, age-dependent differences between CSC populations have primarily been explored with bulk sequencing methods. In this work, we hypothesized that differences in CSC populations and subsequent cell therapy outcomes may arise from differing cell subtypes within donor CSC samples. We performed single-cell RNA sequencing on four neonatal CSC (nCSC) and five child CSC (cCSC) samples. Subcluster analysis revealed cCSC-enriched clusters upregulated in several fibrosis- and immune response-related genes. Module-based analysis identified upregulation of chemotaxis and ribosomal activity-related genes in nCSCs and upregulation of immune response and fiber synthesis genes in cCSCs. Further, we identified versican and integrin alpha 2 as potential markers for a fibrotic cell subtype. By investigating differences in patient-derived CSC populations at the single-cell level, this research aims to identify and characterize CSC subtypes to better optimize CSC-based therapy and improve patient outcomes.

Background and purpose KATP channels are negative regulators of lymphatic vessel excitability and contractility and are proposed to be targets for immune cell products that inhibit lymph transport. Previous studies in rat and guinea pig mesenteric lymphatics found that nitric oxide (NO)-mediated inhibition of lymphatic contraction was prevented or reversed by the KATP channel inhibitor, glibenclamide. We revisited this hypothesis using mouse lymphatic vessels and KATP channel knock out mice. Experimental approach Mouse popliteal lymphatics were isolated and contractility was assessed using pressure myography. K+ channel expression was determined by PCR analysis of FACS-purified lymphatic smooth muscle cells. Key results The NO-producing agonist, ACh, and the NO donor, NONOate, both produced dose-dependent inhibition of spontaneous lymphatic contractions that were blocked by the soluble guanylate cyclase inhibitor, ODQ, or the PKG inhibitor, Rp-8-Br-PET-cGMPS. Surprisingly, the inhibitory effects of both were preserved in Kir6.1-/- vessels, suggesting that KATP channels did not mediate NO-induced responses. We hypothesized a role for BK channels, given their prominence in arterial smooth muscle. Indeed, BK channels were expressed in mouse lymphatic smooth muscle and NS11021 (a BK channel activator) caused dilation and reduced contraction frequency, whereas iberiotoxin and Penitrem A (BK channel inhibitors) produced right-shifts in NONOate concentration-response curves. Conclusion and implication NO inhibition of mouse lymphatic contractions primarily involves activation of BK channels rather than KATP channels. Thus, BK channels are a potential target for therapeutic reversal of lymph pump inhibition by NO generated by immune cell activation of iNOS in chronic lymphedema.

_ High-speed ferries of around 100mlength cruising at around 40 knots can cause significant passenger discomfort in head waves. This is due to the frequencies of encountering waves, of maximum hull response to encountered waves and of maximum passenger discomfort all falling within a similar range. In this paper, the benefit obtained by fitting active T-foils and stern tabs to control heave and pitch in head waves is considered. Ship motion responses are computed by numerical integration in the time domain including unsteady control actions using a time domain, high-speed strip theory. This obviates the need to identify transfer functions, the computed time responses including nonlinear hull immersion terms. The largest passenger vertical accelerations occur at forward locations and are best controlled by a forward located T-foil acting in combination with active stern tabs. Various feedback control algorithms have been considered and it is found that pitch damping control gives the greatest improvement in passenger comfort at forward positions. Operation in adaptive and nonlinear modes so that the control deflections are maximized under all conditions give the greatest benefit and can reduce passenger motion sickness incidence (MSI) by up to 25% in a 3-mhead sea on the basis of International Organization for Standardization (ISO) recommendations for calculation of MSI for a 90-minute seaway passage. Introduction When the first high-speed, lightweight catamaran car ferries were developed, it quickly became apparent that motion control systems were desirable to improve passenger comfort. This was a direct consequence of the high operating Froude numbers (based on waterline length) of up to 0.75, which gave rise to heave and pitch motions in excess of the wave height and wave slope. It was also a consequence of the period of encountered waves at high speed that becomes close to the period at which passengers would experience significant motion discomfort, approximately 5-6 seconds. As a consequence, active motion controls were introduced and have been fitted to most vessels operating on routes where significant wave heights might reach or exceed approximately 3m.

Following a decision to require label warnings for concurrent use of opioids and benzodiazepines and increased risk of respiratory depression and death, the US Food and Drug Administratioin (FDA) recognized that other sedative psychotropic drugs may be substituted for benzodiazepines and be used concurrently with opioids. In some cases, data on the ability of these alternatives to depress respiration alone or in conjunction with an opioid are lacking. A nonclinical in vivo model was developed that could detect worsening respiratory depression when a benzodiazepine (diazepam) was used in combination with an opioid (oxycodone) compared to the opioid alone based on an increased arterial partial pressure of carbon dioxide (pCO2). The current study used that model to assess the impact on respiration of non‐benzodiazepine sedative psychotropic drugs representative of different drug classes (clozapine, quetiapine, risperidone, zolpidem, trazodone, carisoprodol, cyclobenzaprine, mirtazapine, topiramate, paroxetine, duloxetine, ramelteon, and suvorexant) administered alone and with oxycodone. At clinically relevant exposures, paroxetine, trazodone, and quetiapine given with oxycodone significantly increased pCO2 above the oxycodone effect. Analyses indicated that most pCO2 interaction effects were due to pharmacokinetic interactions resulting in increased oxycodone exposure. Increased pCO2 recorded with oxycodone‐paroxetine co‐administration exceeded expected effects from only drug exposure suggesting another mechanism for the increased pharmacodynamic response. This study identified drug‐drug interaction effects depressing respiration in an animal model when quetiapine or paroxetine were co‐administered with oxycodone. Clinical pharmacodynamic drug interaction studies are being conducted with these drugs to assess translatability of these findings.

Exercise often causes skeletal muscle hyperthermia, likely resulting in decreased efficiency of mitochondrial respiration. We hypothesized that athletic conditioning would improve mitochondrial tolerance to hyperthermia. Skeletal muscle biopsies were obtained from six Alaskan sled dogs under light general anesthesia before and after a full season of conditioning and racing, and respiration of permeabilized muscle fibers was measured at 38, 40, 42, and 44°C. There was no effect of temperature on phosphorylating respiration, and athletic conditioning increased maximal phosphorylating respiration by 19%. Leak respiration increased and calculated efficiency of oxidative phosphorylation decreased with increasing incubation temperature, and athletic conditioning resulted in higher leak respiration and lower calculated oxidative phosphorylation efficiency at all temperatures. Conditioning increased skeletal muscle expression of putative mitochondrial leak pathways adenine nucleotide transporter 1 and uncoupling protein 3, both of which were correlated with the magnitude of leak respiration. We conclude that athletic conditioning in elite canine endurance athletes results in increased capacity for mitochondrial proton leak that potentially reduces maximal mitochondrial membrane potential during periods of high oxidative phosphorylation. This effect may provide a mechanistic explanation for previously reported decreases in exercise-induced muscle damage in well-conditioned subjects.

In early March 2020, Johns Hopkins University Applied Physics Lab hosted an Association of Military Surgeons of the United States regional conference to address medical demands of the future battlefield for which prolonged field care is expected. Arising from this conference, we propose here an approach to prolonged field care research—and also summarize the major concepts discussed at the conference. We draw parallels to prolonged field care investments and advancements that apply beyond the combat environment. The exceedingly daunting medical challenges of the future battlefield, on land and at sea, must be addressed to maintain an effective force able to compete with modern highly capable adversaries. Since the human element, and its health, will allow future mission success, we propose here an approach to making soldier health-related research most impactful.

Wave slam produces dynamic loads on the centre bow of wave piercing catamarans that are related to the relative vertical motion of the bow to the encountered wave surface. Rapid slam forces arise when the arch sections between centre bow and main hulls fill with rising water. In this paper time domain solutions for high speed ship motion in waves, including the action of active motion controls, are used to compute the slam forces. Slamming occurs at specific immersions of the bow whilst the peak slam force is characterised by the maximum relative vertical velocity of the bow during bow entry. Vertical motions of bow and encountered wave are in antiphase at encounter frequencies where slamming is most severe. The range of encounter frequencies where slamming occurs increases with wave height. Wave slam loads reduce ship motions, the heave motion being most reduced. Deployment of a fixed, inactive T-foil can reduce slamming loads by up to 65 %. With active controls peak slamming loads on the bow can be reduced by up to 73% and 79% in 4 m and 3 m seas, local control feedback being marginally the most effective mode of control for reduction of slamming.

BackgroundHypoplastic left heart syndrome (HLHS) survival relies on surgical reconstruction for the right ventricle (RV) to provide systemic circulation. This leads to substantially increased loads on the RV, wall stress, maladaptive remodeling and dysfunction, which in turn can increase risk of death or transplantation.ObjectivesWe conducted a phase I multicenter trial to assess safety and feasibility of intra-operative MSC injection in HLHS patients to boost RV performance in the systemic position.MethodsAllogeneic MSCs were directly administered by intramyocardial injections during the second stage palliative operation. The primary endpoint was safety.ResultsTen patients received intramyocardial injections of allogeneic MSCs (Lomecel-B). No patients experienced major adverse cardiac events (MACE). All subjects were alive and transplant-free at 1 year following, and experienced growth comparable to healthy control historical data. Cardiac magnetic resonance imaging (CMR) revealed improving tricuspid regurgitant fraction (Baseline: 0.45±0.19; 6 mo.: 0.32±0.06; 12 mo.: 0.06±0.09), while global longitudinal strain (Baseline: -24.39±6.99; 6 mo.: -20.55±3.05, p > 0.05 vs baseline; 12 mo.: - 23.88±4.6, p>0.05 vs baseline) and RV ejection fraction (EF; baseline: 62.62±5.99; 6 mo.: 53.69±9.56; 12 mo.: 52.31±5.63: p=NS for change over time) were unchanged. Computational modeling identified 167 derived RNAs specific to circulating exosomes originating from transplanted MSCs corresponding to RVEF changes and identifying potential mechanistic underpinnings.ConclusionsIntramyocardial MSCs appear safe in HLHS patients, and may favorably affect RV performance. Circulating exosomes of transplanted MSC-specific provide novel insight into bioactivity. Conduct of a controlled phase trial is warranted and is underway.Condensed AbstractThe ELPIS phase I trial was designed to assess safety and feasibility of intramyocardial injection of allogeneic MSCs into the RV during second stage palliation of HLHS. There were no incidences of major adverse cardiac events (MACE) or other safety concerns, and there was a 100% transplant-free survival at 1-year follow-up, supporting the safety and feasibility of this approach. The ELPIS results are important for advancing MSC therapy for all ages and congenital heart conditions, and warrant further investigation in a controlled Phase II trial powered for efficacy.

Lungs balance threat from primary viral infection, secondary infection, and inflammatory damage. Severe pulmonary inflammation induces vascular permeability, edema, and organ dysfunction. We previously demonstrated that poly(I:C) (pICLC) induced type 1 interferon (t1IFN) protected mice fromCryptococcus gattii(Cg)vialocal iron restriction. Here we show pICLC increased serum protein and intravenously injected FITC-dextran in the lung airspace suggesting pICLC induces vascular permeability. Interestingly, pICLC induced a pro-inflammatory signature with significant expression of IL-1 and IL-6 which depended on MDA5 and t1IFN. Vascular permeability depended on MDA5, t1IFN, IL-1, and IL-6. T1IFN also induced MDA5 and other MDA5 signaling components suggesting that positive feedback contributes to t1IFN dependent expression of the pro-inflammatory signature. Vascular permeability, induced by pICLC or another compound, inhibited Cg by limiting iron. These data suggest that pICLC induces t1IFN which potentiates pICLC-MDA5 signaling increasing IL-1 and IL-6 resulting in leakage of antimicrobial serum factors into lung airspace. Thus, induced vascular permeability may act as an innate defense mechanism against opportunistic fungal infection, such as cryptococcosis, and may be exploited as a host-directed therapeutic target.

Fibronectin (FN) enhances K+ channel activity by integrin-mediated mechanisms. As vascular smooth muscle (VSM) K+ channels mediate vasodilation, we hypothesized that modification of fibronectin, via advanced non-enzymatic glycation, would alter signaling of this extracellular matrix protein through these channels. Bovine FN (1 mg/ml) was glycated (gFN) for 5 days using methylglyoxal (50 mM), and albumin was similarly glycated as a non-matrix protein control. VSM cells were isolated from rat cerebral arteries for measurement of macroscopic K+ channel activity using whole cell patch clamp methodology. Pharmacological inhibitors, iberiotoxin (0.1 μM) and 4-aminopyridine (0.1 mM), were used to identify contributions of large-conductance, Ca2+-activated, K+ channels and voltage-gated K+ channels, respectively. Compared with baseline, native FN enhanced whole cell K+ current in a concentration-dependent manner, whereas gFN inhibited basal current. Furthermore, native albumin did not enhance basal K+ current, but the glycated form (gAlb) caused inhibition. gFN was shown to impair both the Kv and BKCa components of total macroscopic K+ current. Anti-integrin α5 and β1 antibodies attenuated the effects of both FN and gFN on macroscopic K+ current at +70 mV. Consistent with an action on BKCa activity, FN increased, whereas gFN decreased the frequency of spontaneous transient outward current (STOCs). In contrast, gAlb inhibited whole cell K+ current predominantly through Kv, showing little effect on STOCs. A function-blocking, anti-RAGE antibody partially reversed the inhibitory effects of gFN, suggesting involvement of this receptor. Further, gFN caused production of reactive oxygen species (ROS) by isolated VSMCs as revealed by the fluorescent indicator, DHE. Evoked ROS production was attenuated by the RAGE blocking antibody. Collectively, these studies identify ion channel-related mechanisms (integrin and ROS-mediated) by which protein glycation may modify VSMC function.

The skeletal muscle of exercising horses develops pronounced hyperthermia and acidosis during strenuous or prolonged exercise, with very high tissue temperature and low pH associated with muscle fatigue or damage. The purpose of this study was to evaluate the individual effects of physiologically relevant hyperthermia and acidosis on equine skeletal muscle mitochondrial function, using ex vivo measurement of oxygen consumption to assess the function of different mitochondrial elements. Fresh triceps muscle biopsies from 6 healthy unfit Thoroughbred geldings were permeabilised to permit diffusion of small molecular weight substrates through the sarcolemma and analysed in a high resolution respirometer at 38, 40, 42, and 44 °C, and pH=7.1, 6.5, and 6.1. Oxygen consumption was measured under conditions of non-phosphorylating (leak) respiration and phosphorylating respiration through Complex I and Complex II. Data were analysed using a one-way repeated measures ANOVA and data are expressed as mean ± standard deviation. Leak respiration was ~3-fold higher at 44 °C compared to 38 °C regardless of electron source (Complex I: 22.88±3.05 vs 8.08±1.92 pmol O2/mg/s), P=0.002; Complex II: 79.14±23.72 vs 21.43±11.08 pmol O2/mg/s, P=0.022), resulting in a decrease in efficiency of oxidative phosphorylation. Acidosis had minimal effect on mitochondrial respiration at pH=6.5, but pH=6.1 resulted in a 50% decrease in mitochondrial oxygen consumption. These results suggest that skeletal muscle hyperthermia decreases the efficiency of oxidative phosphorylation through increased leak respiration, thus providing a specific biochemical basis for hyperthermia-induced muscle fatigue. The effect of myocellular acidosis on mitochondrial respiration was minimal under typical levels of acidosis, but atypically severe acidosis can lead to impairment of mitochondrial function.

Background: Severe weight loss commonly occurs before and during chemo-irradiation for Stage III and IV SCCHN. Nevertheless, the effects of severe weight loss on short and long term outcomes are unknown. Objective: To evaluate effects of pre-treatment weight loss versus weight loss during chemotherapy/radiation for advanced operable SCCHN on toxicity, tumor response, recurrent tumor and survival. Methods: Records of 52 patients with Stage III and IV, clinically operable SCCHN who underwent primary high-dose radiotherapy and concomitant chemotherapy (cisplatin, 20mg/M2/four consecutive days during weeks 1, 4, and 7 of radiotherapy) (CTRT) were examined retrospectively in two groups: 7.5% weight loss (SEVERE; n=41). Data included tumor site, grade, stage, pre-CTRT weight loss, CTRT toxicity, response (CCR = Clinical Complete; HCR = Histologic Complete without residual tumor), surgeries, recurrence, and overall and disease-free survival. Statistical analysis: Chi-square, ANOVA, and Kaplan-Meier. Results: Per study design, weight loss was greater in the SEVERE group versus NON-SEVERE (-17.3% +- 7.9% versus -2.9% +- 4.2%, p

Objectives: The objective was to compare dental visits, procedures, and expenditures in children with newly diagnosed caries. Study design: A retrospective chart review was conducted in a two dentist private practice in North Carolina. Demographic data, health status, and dental treatment data was collected. Analysis relied upon nearest neighbor matching to estimate the average treatment effects of silver diamine fluoride (SDF) by comparing children who received SDF to children who did not receive SDF (n=104 matches). Results: After matching on age, gender, race, insurance status, dental cooperation, and dmft, the SDF group had significantly more dental visits (average treatment effect on treated (ATET)=1.08), fewer restorations (ATET=2.37), and fewer restorative and overall treatment expenditures (ATET=$402 and $292, respectively) than the non-SDF group. The SDF group more frequently received treatment under general anesthesia (26% vs 7%), so this group was excluded in secondary analysis. Among children who did not receive general anesthesia, the SDF group had significantly more dental visits (ATET=.66), fewer restorations (ATET=2.74), and fewer restorative and overall treatment expenditures (ATET=$566 and $515, respectively) than the non-SDF group. Conclusion: SDF can offer cost savings when used as an adjunct to, rather than a complete replacement for, restorative treatment in young children.

BACKGROUND: Low airway surface pH is associated with many airway diseases, impairs antimicrobial host defense, and worsens airway inflammation. Inhaled Optate is designed to safely raise airway surface pH and is well tolerated in humans. Raising intracellular pH partially prevents activation of SARS-CoV-2 in primary normal human airway epithelial (NHAE) cells, decreasing viral replication by several mechanisms. METHODS: We grew primary NHAE cells from healthy subjects, infected them with SARS-CoV-2 (isolate USA-WA1/2020), and used clinical Optate at concentrations used in humans in vivo to determine whether Optate would prevent viral infection and replication. Cells were pretreated with Optate or placebo prior to infection (multiplicity of infection = 1), and viral replication was determined with plaque assay and nucleocapsid (N) protein levels. Healthy human subjects also inhaled Optate as part of a Phase 2a safety trial. RESULTS: Optate almost completely prevented viral replication at each time point between 24 h and 120 h, relative to placebo, on both plaque assay and N protein expression (P < .001). Mechanistically, Optate inhibited expression of major endosomal trafficking genes and raised NHAE intracellular pH. Optate had no effect on NHAE cell viability at any time point. Inhaled Optate was well tolerated in 10 normal subjects, with no change in lung function, vital signs, or oxygenation. CONCLUSIONS: Inhaled Optate may be well suited for a clinical trial in patients with pulmonary SARS-CoV-2 infection. However, it is vitally important for patient safety that formulations designed for inhalation with regard to pH, isotonicity, and osmolality be used. An inhalational treatment that safely prevents SARS-CoV-2 viral replication could be helpful for treating patients with pulmonary SARS-CoV-2 infection.

Low dissolved oxygen, or hypoxia, is a common phenomenon in ice-covered lakes in winter. We measured dissolved oxygen (DO) before, during, and after ice-over to characterize the timing, severity, and spatial variability of winter hypoxia in Upper Red Rock Lake, Montana, home to one of the last remaining lacustrine populations of endemic Montana Arctic Grayling (Thymallus arcticus). Unlike most previous investigations of winterkill-prone lakes, we observed considerable horizontal spatial variability in DO, a non-linear winter oxygen depletion rate, and lake-wide re-oxygenation 2–4 weeks prior to spring ice loss. Parts of the upper 1 m of the lake and near stream mouths remained well-oxygenated even during late winter. DO levels were strongly associated with maximum daily air temperature. Our analysis of a 28-year weather record revealed large interannual variability in risk of winter hypoxia, with a slight declining trend in winter severity (number of days with maximum air temperatures ≤ 0°C) in Upper Red Rock Lake. The approach we used in our study provides a useful framework for quantifying and mapping the seasonal dynamics of the extent and severity of winter hypoxia, and for identifying critical winter habitats.

The world’s first hand transplant was performed for a serviceman in 1964, following a blast injury. Despite a need for such effective reconstruction of military wounds, only eight further transplants have been performed for injured soldiers. This review analysed the specific factors that have informed the use of vascularized composite allotransplantation (VCA) in military patients. Nine servicemembers have received reconstructive transplants worldwide. Seven have received upper limb transplants, one a partial face transplant and one a penile transplant. These have been in Ecuador, the USA, Poland, India and Russia. Countries with clinical VCA programmes in military hospitals include Vietnam and China, whilst others have active pre-clinical VCA research programmes including the USA, the UK and Canada. Despite specific concerns in reconstructing military patients using VCA, outcomes have improved in the last decade and the field has evolved to include more complex tissue composites, across more international centres.

There is limited information regarding the use of risk assessment tools with aging offender populations. It is known that the likelihood of offending behaviour decreases with age, a small group of men either continue or begin to offend sexually in the later decades of life. The current study investigated the predictive validity of the Static-99 and the Static-99R, in a sample of convicted Australian sex offenders aged 50 and older. A sample of 118 participants was identified, of which 17 (14.4%) re-offended within a follow-up period ranging from four months to 20 years (M = 9.07 years). There were seven recidivists (13.46%) above the age of 60 years (n = 52) and 10 aged 40 to 59.9 years (n = 66). Both the Static-99 and Static-99R demonstrated moderate predictive validity with both age groups. The limitations of this study are discussed as well as recommendations for future research.

Key points Spontaneous contractions are essential for normal lymph transport and these contractions are exquisitely sensitive to the KATP channel activator pinacidil. KATP channel Kir6.1 and SUR2B subunits are expressed in mouse lymphatic smooth muscle (LSM) and form functional KATP channels as verified by electrophysiological techniques. Global deletion of Kir6.1 or SUR2 subunits results in severely impaired lymphatic contractile responses to pinacidil. Smooth muscle-specific expression of Kir6.1 gain-of-function mutant (GoF) subunits results in profound lymphatic contractile dysfunction and LSM hyperpolarization that is partially rescued by the KATP inhibitor glibenclamide. In contrast, lymphatic endothelial-specific expression of Kir6.1 GoF has essentially no effect on lymphatic contractile function. The high sensitivity of LSM to KATP channel GoF offers an explanation for the lymphoedema observed in patients with Cantu syndrome, a disorder caused by gain-of-function mutations in genes encoding Kir6.1 or SUR2, and suggests that glibenclamide may be an appropriate therapeutic agent. Abstract This study aimed to understand the functional expression of KATP channel subunits in distinct lymphatic cell types, and assess the consequences of altered KATP channel activity on lymphatic pump function. KATP channel subunits Kir6.1 and SUR2B were expressed in mouse lymphatic muscle by PCR, but only Kir6.1 was expressed in lymphatic endothelium. Spontaneous contractions of popliteal lymphatics from wild-type (WT) (C57BL/6J) mice, assessed by pressure myography, were very sensitive to inhibition by the SUR2-specific KATP channel activator pinacidil, which hyperpolarized both mouse and human lymphatic smooth muscle (LSM). In vessels from mice with deletion of Kir6.1 (Kir6.1-/- ) or SUR2 (SUR2[STOP]) subunits, contractile parameters were not significantly different from those of WT vessels, suggesting that basal KATP channel activity in LSM is not an essential component of the lymphatic pacemaker, and does not exert a strong influence over contractile strength. However, these vessels were >100-fold less sensitive than WT vessels to pinacidil. Smooth muscle-specific expression of a Kir6.1 gain-of-function (GoF) subunit resulted in severely impaired lymphatic contractions and hyperpolarized LSM. Membrane potential and contractile activity was partially restored by the KATP channel inhibitor glibenclamide. In contrast, lymphatic endothelium-specific expression of Kir6.1 GoF subunits had negligible effects on lymphatic contraction frequency or amplitude. Our results demonstrate a high sensitivity of lymphatic contractility to KATP channel activators through activation of Kir6.1/SUR2-dependent channels in LSM. In addition, they offer an explanation for the lymphoedema observed in patients with Cantu syndrome, a disorder caused by gain-of-function mutations in genes encoding Kir6.1/SUR2.

Key points Lymphatic valve defects are one of the major causes of lymph transport dysfunction; however, there are no accessible methods for quantitatively assessing valve function. This report describes a novel technique for quantifying lymphatic valve back-leak. Postnatal endothelial-specific deletion of connexin 43 (Cx43) in connexin 37 null (Cx37-/- ) mice results in rapid regression of valve leaflets and severe valve dysfunction. This method can also be used for assessing the function of venous and lymphatic valves from various species, including humans. Abstract The lymphatic system relies on robust, spontaneous contractions of collecting lymphatic vessels and one-way secondary lymphatic valves to efficiently move lymph forward. Secondary valves prevent reflux and allow for the generation of propulsive pressure during each contraction cycle. Lymphatic valve defects are one of the major causes of lymph transport dysfunction. Genetic mutations in multiple genes have been associated with the development of primary lymphoedema in humans; and many of the same mutations in mice result in valve defects that subsequently lead to chylous ascites or chylothorax. At present the only experimental technique for the quantitative assessment of lymphatic valve function utilizes the servo-null micropressure system, which is highly accurate and precise, but relatively inaccessible and difficult to use. We developed a novel, simplified alternative method for quantifying valve function and determining the degree of pressure back-leak through an intact valve in pressurized, single-valve segments of isolated lymphatic vessels. With this diameter-based method, the competence of each lymphatic valve is challenged over a physiological range of pressures (e.g. 0.5-10cmH2 O) and pressure back-leak is extrapolated from calibrated, pressure-driven changes in diameter upstream from the valve. Using mesenteric lymphatic vessels from C57BL/6J, Ub-CreERT2 ;Rasa1fx/fx , Foxc2Cre/+ , Lyve1-Cre;Cx43fx/fx , and Prox1-CreERT2 ;Cx43fx/fx ;Cx37-/- mice, we tested our method on lymphatic valves displaying a wide range of dysfunction, from fully competent to completely incompetent. Our results were validated by simultaneous direct measurement of pressure back-leak using a servo-null micropressure system. Our diameter-based technique can be used to quantify valve function in isolated lymphatic valves from a variety of species. This method also revealed that haplodeficiency in Foxc2 (Foxc2Cre/+ ) is not sufficient to cause significant valve dysfunction; however, postnatal endothelial-specific deletion of Cx43 in Cx37-/- mice results in rapid regression of valve leaflets and severe valve dysfunction.

Background Diagnosis of lung injury requires invasive blood draws to measure oxygen tension in blood. This capability is nonexistent in austere settings and during prolonged field care (PFC), that is, medical care characterized by inability to evacuate casualties from the point of injury for up to 72 hours. We analyzed pulse-oximeter-derived noninvasive SpO2 and assessed the SpO2/FiO2 ratio (SFR) as a surrogate for the PaO2/FiO2 ratio (PFR), an accepted marker of lung function. We hypothesized that SFR is a suitable surrogate for PFR in a data set from animal models of combat-relevant trauma, PFC, and aeromedical evacuation. Methods Data from anesthetized swine (N = 30) subjected to combat relevant trauma, resuscitation, and critical care interventions were analyzed. Pairwise correlations and Bland-Altman and regression analyses were performed to compare PFR and SFR, based on averaged SpO2 values obtained from two monitoring devices. Results We performed 683 pairwise correlations. SpO2/FiO2 ratio was numerically higher than PFR with a 313 cutoff values for acute respiratory distress syndrome (ARDS) (PFR ≥300). Sensitivity/specificity for detection of mild ARDS was 75%/73% with a 200 to 300 PFR range corresponding to 252 to 312 SFR range. For moderate ARDS, sensitivity/specificity was 61%/93% with a 100 to 200 PFR range corresponding to 191 to 251 SFR range. For severe ARDS, sensitivity/specificity was 49%/97% with a 0 to 100 PFR range corresponding to 0 to 190 SFR range. For all groups, areas under the receiver operating characteristic curves ranged from 0.76 to 0.98. Conclusion SpO2/FiO2 ratio is a useful surrogate for PFR when arterial blood gas testing is not available during dynamically changing physiologic conditions, for example, during austere conditions, PFC, or aeromedical evacuation, and may permit early detection of casualties in need of lung-specific life-saving interventions. Studies in critically ill humans are warranted.