Ni2P active site ensembles tune electrocatalytic nitrate reduction selectivity.

We demonstrate that active site ensembles on transition metal phosphides tune the selectivity of the nitrate reduction reaction. Using Ni2P nanocrystals as a case study, we report a mechanism involving competitive co-adsorption of H* and NOx* intermediates. A near 100% faradaic efficiency for nitrate reduction over hydrogen evolution is observed at -0.4 V, while NH3 selectivity is maximized at -0.2 V vs. RHE.

Evaluation of renal sodium handling in heart failure with preserved ejection fraction: A pilot study.

The pathophysiology behind sodium retention in heart failure with preserved ejection fraction (HFpEF) remains poorly understood. We hypothesized that patients with HFpEF have impaired natriuresis and diuresis in response to volume expansion and diuretic challenge, which is associated with renal hypo-responsiveness to endogenous natriuretic peptides. Nine HFpEF patients and five controls received saline infusion (0.25 mL/kg/min for 60 min) followed by intravenous furosemide (20 mg or home dose) 2 h after the infusion. Blood and urine samples were collected at baseline, 2 h after saline infusion, and 2 h after furosemide administration; urinary volumes were recorded. The urinary cyclic guanosine monophosphate (ucGMP)/plasma B-type NP (BNP) ratio was calculated as a measure of renal response to endogenous BNP. Wilcoxon rank-sum test was used to compare the groups. Compared to controls, HFpEF patients had reduced urine output (2480 vs.3541 mL; p = 0.028), lower urinary sodium excretion over 2 h after saline infusion (the percentage of infused sodium excreted 12% vs. 47%; p = 0.003), and a lower baseline ucGMP/plasma BNP ratio (0.7 vs. 7.3 (pmol/mL)/(mg/dL)/(pg/mL); p = 0.014). Patients with HFpEF had impaired natriuretic response to intravenous saline and furosemide administration and lower baseline ucGMP/plasma BNP ratios indicating renal hypo-responsiveness to NPs.

Prosthetic fitting and mortality after major lower extremity amputation.

BACKGROUND: Studies suggest that ambulation after major lower extremity amputation (LEA) is low and mortality after LEA is high. Successful prosthetic fitting after LEA has a significant quality of life benefit; however, it is unclear if there are benefits in post-LEA mortality. Our objective was to examine a contemporary cohort of patients who underwent LEA and determine if there is an association between fitting for a prosthetic and mortality. METHODS: We reviewed all patients who underwent LEA between 2015 and 2022 at two academic health care systems in a large metropolitan city. The exposure of interest was prosthetic fitting after LEA. The primary outcomes were mortality within 1 and 3 years of follow-up. Ambulation after LEA was defined as being ambulatory with or without an assistive device. Patients with prior LEA were excluded. Extended Cox models with time-dependent exposure were used to evaluate the association between prosthetic fitting and mortality at 1 and 3 years of follow-up. RESULTS: Among 702 patients who underwent LEA, the mean (SD) age was 64.3 (12.6) years and 329 (46.6%) were fitted for prosthetic. The study population was mostly male (n = 488, 69.5%), predominantly non-Hispanic Black (n = 410, 58.4%), and nearly one-fifth were non-ambulatory before LEA (n = 139 [19.8%]). Of note, 14.3% of all subjects who were nonambulatory at some point after LEA, and 28.5% of patients not ambulatory preoperatively were eventually ambulatory after LEA. The rate of death among those fitted for a prosthetic was 12.0/100 person-years at 1 year and 5.8/100 person-years at 3 years of follow-up; among those not fitted for a prosthetic, the rate of death was 55.7/100 person-years and 50.7/100 person-years at 1 and 3 years of follow-up, respectively. After adjusting for several sociodemographic data points, comorbidities, pre- or post- coronavirus disease 2019 pandemic timeframe, and procedural factors, prosthetic fitting is associated with decreased likelihood of mortality within 1 year of follow-up (adjusted hazard ratio, 0.24; 95% confidence interval, 0.14-0.40) as well as within 3 years (adjusted hazard ratio, 0.40; 95% confidence interval, 0.29-0.55). CONCLUSIONS: Prosthetic fitting is associated with improved survival, and preoperative functional status does not always predict postoperative functional status. Characterizing patient, surgical, and rehabilitation factors associated with receipt of prosthetic after LEA may improve long-term survival in these patients. Process measures employed by the Department of Veterans Affairs, such as prosthetic department evaluation of all amputees, may represent a best practice.

Impact of osteoporosis and osteoporosis medications on fracture healing: a narrative review.

Antiresorptive medications do not negatively affect fracture healing in humans. Teriparatide may decrease time to fracture healing. Romosozumab has not shown a beneficial effect on human fracture healing. BACKGROUND: Fracture healing is a complex process. Uncertainty exists over the influence of osteoporosis and the medications used to treat it on fracture healing. METHODS: Narrative review authored by the members of the Fracture Working Group of the Committee of Scientific Advisors of the International Osteoporosis Foundation (IOF), on behalf of the IOF and the Société Internationale de Chirurgie Orthopédique et de Traumatologie (SICOT). RESULTS: Fracture healing is a multistep process. Most fractures heal through a combination of intramembranous and endochondral ossification. Radiographic imaging is important for evaluating fracture healing and for detecting delayed or non-union. The presence of callus formation, bridging trabeculae, and a decrease in the size of the fracture line over time are indicative of healing. Imaging must be combined with clinical parameters and patient-reported outcomes. Animal data support a negative effect of osteoporosis on fracture healing; however, clinical data do not appear to corroborate with this. Evidence does not support a delay in the initiation of antiresorptive therapy following acute fragility fractures. There is no reason for suspension of osteoporosis medication at the time of fracture if the person is already on treatment. Teriparatide treatment may shorten fracture healing time at certain sites such as distal radius; however, it does not prevent non-union or influence union rate. The positive effect on fracture healing that romosozumab has demonstrated in animals has not been observed in humans. CONCLUSION: Overall, there appears to be no deleterious effect of osteoporosis medications on fracture healing. The benefit of treating osteoporosis and the urgent necessity to mitigate imminent refracture risk after a fracture should be given prime consideration. It is imperative that new radiological and biological markers of fracture healing be identified. It is also important to synthesize clinical and basic science methodologies to assess fracture healing, so that a convergence of the two frameworks can be achieved.

Synthesis and Single Crystal X-ray Diffraction Structure of an Indium Arsenide Nanocluster.

The discovery of magic-sized clusters as intermediates in the synthesis of colloidal quantum dots has allowed for insight into formation pathways and provided atomically precise molecular platforms for studying the structure and surface chemistry of those materials. The synthesis of monodisperse InAs quantum dots has been developed through the use of indium carboxylate and As(SiMe3)3 as precursors and documented to proceed through the formation of magic-sized intermediates. Herein, we report the synthesis, isolation, and single-crystal X-ray diffraction structure of an InAs nanocluster that is ubiquitous across reports of InAs quantum dot synthesis. The structure, In26As18(O2CR)24(PR'3)3, differs substantially from previously reported semiconductor nanocluster structures even within the III-V family. However, it can be structurally linked to III-V and II-VI cluster structures through the anion sublattice. Further analysis using variable temperature absorbance spectroscopy and support from computation deepen our understanding of the reported structure and InAs nanomaterials as a whole.

Salt-Sensitive Hypertension and the Kidney.

Salt-sensitive hypertension (SS-HT) is characterized by blood pressure elevation in response to high dietary salt intake and is considered to increase the risk of cardiovascular and renal morbidity. Although the mechanisms responsible for SS-HT are complex, the kidneys are known to play a central role in the development of SS-HT and the salt sensitivity of blood pressure (SSBP). Moreover, several factors influence renal function and SSBP, including the renin-angiotensin-aldosterone system, sympathetic nervous system, obesity, and aging. A phenotypic characteristic of SSBP is aberrant activation of the renin-angiotensin system and sympathetic nervous system in response to excessive salt intake. SSBP is also accompanied by a blunted increase in renal blood flow after salt loading, resulting in sodium retention and SS-HT. Obesity is associated with inappropriate activation of the aldosterone mineralocorticoid receptor pathway and renal sympathetic nervous system in response to excessive salt, and mineralocorticoid receptor antagonists and renal denervation attenuate sodium retention and inhibit salt-induced blood pressure elevation in obese dogs and humans. SSBP increases with age, which has been attributed to impaired renal sodium handling and a decline in renal function, even in the absence of kidney disease. Aging-associated changes in renal hemodynamics are accompanied by significant alterations in renal hormone levels and renal sodium handling, resulting in SS-HT. In this review, we focus mainly on the contribution of renal function to the development of SS-HT.

Protocol for a parallel cluster randomized trial of a participatory tailored approach to reduce overuse of antibiotics at hospital discharge: the ROAD home trial.

BACKGROUND: Antibiotic overuse at hospital discharge is common, costly, and harmful. While discharge-specific antibiotic stewardship interventions are effective, they are resource-intensive and often infeasible for hospitals with resource constraints. This weakness impacts generalizability of stewardship interventions and has health equity implications as not all patients have access to the benefits of stewardship based on where they receive care. There may be different pathways to improve discharge antibiotic prescribing that vary widely in feasibility. Supporting hospitals in selecting interventions tailored to their context may be an effective approach to feasibly reduce antibiotic overuse at discharge across diverse hospitals. The objective of this study is to evaluate the effectiveness of the Reducing Overuse of Antibiotics at Discharge Home multicomponent implementation strategy ("ROAD Home") on antibiotic overuse at discharge for community-acquired pneumonia and urinary tract infection. METHODS: This 4-year two-arm parallel cluster-randomized trial will include three phases: baseline (23 months), intervention (12 months), and postintervention (12 months). Forty hospitals recruited from the Michigan Hospital Medicine Safety Consortium will undergo covariate-constrained randomization with half randomized to the ROAD Home implementation strategy and half to a "stewardship as usual" control. ROAD Home is informed by the integrated-Promoting Action on Research Implementation in Health Services Framework and includes (1) a baseline needs assessment to create a tailored suite of potential stewardship interventions, (2) supported decision-making in selecting interventions to implement, and (3) external facilitation following an implementation blueprint. The primary outcome is baseline-adjusted days of antibiotic overuse at discharge. Secondary outcomes include 30-day patient outcomes and antibiotic-associated adverse events. A mixed-methods concurrent process evaluation will identify contextual factors influencing the implementation of tailored interventions, and assess implementation outcomes including acceptability, feasibility, fidelity, and sustainment. DISCUSSION: Reducing antibiotic overuse at discharge across hospitals with varied resources requires tailoring of interventions. This trial will assess whether a multicomponent implementation strategy that supports hospitals in selecting evidence-based stewardship interventions tailored to local context leads to reduced overuse of antibiotics at discharge. Knowledge gained during this study could inform future efforts to implement stewardship in diverse hospitals and promote equity in access to the benefits of quality improvement initiatives. TRIAL REGISTRATION: Clinicaltrials.gov NCT06106204 on 10/30/23.

Discovery of lirafugratinib (RLY-4008), a highly selective irreversible small-molecule inhibitor of FGFR2.

Fibroblast growth factor receptor (FGFR) kinase inhibitors have been shown to be effective in the treatment of intrahepatic cholangiocarcinoma and other advanced solid tumors harboring FGFR2 alterations, but the toxicity of these drugs frequently leads to dose reduction or interruption of treatment such that maximum efficacy cannot be achieved. The most common adverse effects are hyperphosphatemia caused by FGFR1 inhibition and diarrhea due to FGFR4 inhibition, as current therapies are not selective among the FGFRs. Designing selective inhibitors has proved difficult with conventional approaches because the orthosteric sites of FGFR family members are observed to be highly similar in X-ray structures. In this study, aided by analysis of protein dynamics, we designed a selective, covalent FGFR2 inhibitor. In a key initial step, analysis of long-timescale molecular dynamics simulations of the FGFR1 and FGFR2 kinase domains allowed us to identify differential motion in their P-loops, which are located adjacent to the orthosteric site. Using this insight, we were able to design orthosteric binders that selectively and covalently engage the P-loop of FGFR2. Our drug discovery efforts culminated in the development of lirafugratinib (RLY-4008), a covalent inhibitor of FGFR2 that shows substantial selectivity over FGFR1 (~250-fold) and FGFR4 (~5,000-fold) in vitro, causes tumor regression in multiple FGFR2-altered human xenograft models, and was recently demonstrated to be efficacious in the clinic at doses that do not induce clinically significant hyperphosphatemia or diarrhea.

Attitudes Toward Injury-Prevention Program Participation Based on Race and Collegiate Division in Female Athletes.

CONTEXT: Injury-prevention programs (IPPs) have been effective in reducing lower extremity injury rates, but user compliance plays a major role in their effectiveness. Race and collegiate division may affect attitudes toward participation in IPPs and compliance in female collegiate athletes. OBJECTIVE: To compare attitudes toward IPPs based on race and collegiate division. DESIGN: Cross-sectional study. SETTING: Survey. PATIENTS OR OTHER PARTICIPANTS: A total of 118 female collegiate athletes (age = 19.71 ± 1.47 years, height = 169.46 ± 9.09 cm, mass = 69.57 ± 11.57 kg) volunteered. MAIN OUTCOME MEASURE(S): Participants completed the Health Belief Model Scale and the Theory of Planned Behavior Scale (TPBS) on 1 occasion. The Health Belief Model Scale contains 9 subscales (perceived susceptibility, perceived consequences, fear of injury, perceived benefits, perceived barriers, community-led self-efficacy, individual self-efficacy, general health cues, external health cues), whereas the TPBS has 5 subscales (perceived benefits, perceived barriers, perceived social norms, social influence, intention to participate). The independent variables were race (White versus Black, Indigenous, and other people of color [BIPOC]) and National Collegiate Athletic Association division (I and III). Mann-Whitney U tests were used to detect differences in attitudes toward IPP participation based on race and collegiate division. RESULTS: White female athletes perceived fewer TPBS barriers to participation in IPPs (P = .003) and more community-led self-efficacy when compared with BIPOC female athletes (P = .009). Division I athletes perceived a greater fear of injury (P = .002) and more general health cues (P = .01) than Division III athletes. CONCLUSIONS: For lower extremity IPPs, BIPOC and Division III female collegiate athletes may need different implementation strategies. Individuals who identify as BIPOC may benefit from interventions focusing on solutions for common barriers to participation and improving community-led self-efficacy, and Division III athletes may benefit from interventions focusing on education related to the risk of injury and general preventive health behaviors.

Ligand Steric Profile Tunes the Reactivity of Indium Phosphide Clusters.

Indium phosphide quantum dots have become an industrially relevant material for solid-state lighting and wide color gamut displays. The synthesis of indium phosphide quantum dots from indium carboxylates and tris(trimethylsilyl)phosphine (P(SiMe3)3) is understood to proceed through the formation of magic-sized clusters, with In37P20(O2CR)51 being the key isolable intermediate. The reactivity of the In37P20(O2CR)51 cluster is a vital parameter in controlling the conversion to quantum dots. Herein, we report structural perturbations of In37P20(O2CR)51 clusters induced by tuning the steric properties of a series of substituted phenylacetate ligands. This approach allows for control over reactivity with P(SiMe3)3, where meta-substituents enhance the susceptibility to ligand displacement, and para-substituents hinder phosphine diffusion to the core. Thermolysis studies show that with complete cluster dissolution, steric profile can modulate the nucleation period, resulting in a nanocrystal size dependence on ligand steric profile. The enhanced stability from ligand engineering also allows for the isolation and structural characterization by single-crystal X-ray diffraction of a new III-V magic-sized cluster with the formula In26P13(O2CR)39. This intermediate precedes the In37P20(O2CR)51 cluster on the InP QD reaction coordinate. The physical and electronic structure of this cluster are analyzed, providing new insight into previously unrecognized relationships between II-VI and III-V materials and the discrete growth of III-V cluster intermediates.

Nanobody-Mediated Dualsteric Engagement of the Angiotensin Receptor Broadens Biased Ligand Pharmacology.

Dualsteric G protein-coupled receptor (GPCR) ligands are a class of bitopic ligands that consist of an orthosteric pharmacophore, which binds to the pocket occupied by the receptor's endogenous agonist, and an allosteric pharmacophore, which binds to a distinct site. These ligands have the potential to display characteristics of both orthosteric and allosteric ligands. To explore the signaling profiles that dualsteric ligands of the angiotensin II type 1 receptor (AT1R) can access, we ligated a 6e epitope tag-specific nanobody (single-domain antibody fragment) to angiotensin II (AngII) and analogs that show preferential allosteric coupling to Gq (TRV055, TRV056) or ß-arrestin (TRV027). While the nanobody itself acts as a probe-specific neutral or negative allosteric ligand of N-terminally 6e-tagged AT1R, nanobody conjugation to orthosteric ligands had varying effects on Gq dissociation and ß-arrestin plasma membrane recruitment. The potency of certain AngII analogs was enhanced up to 100-fold, and some conjugates behaved as partial agonists, with up to a 5-fold decrease in maximal efficacy. Nanobody conjugation also biased the signaling of TRV055 and TRV056 toward Gq, suggesting that Gq bias at AT1R can be modulated through molecular mechanisms distinct from those previously elucidated. Both competition radioligand binding experiments and functional assays demonstrated that orthosteric antagonists (angiotensin receptor blockers) act as non-competitive inhibitors of all these nanobody-peptide conjugates. This proof-of-principle study illustrates the array of pharmacological patterns that can be achieved by incorporating neutral or negative allosteric pharmacophores into dualsteric ligands. Nanobodies directed toward linear epitopes could provide a rich source of allosteric reagents for this purpose. SIGNIFICANCE STATEMENT: Here we engineer bitopic (dualsteric) ligands for epitope-tagged angiotensin II type 1 receptor by conjugating angiotensin II or its biased analogs to an epitope-specific nanobody (antibody fragment). Our data demonstrate that nanobody-mediated interactions with the receptor N-terminus endow angiotensin analogs with properties of allosteric modulators and provide a novel mechanism to increase the potency, modulate the maximal effect, or alter the bias of ligands.

Sesame seed allergy.

ABSTRACT: In the US, sesame was recognized as the ninth major food allergen in 2021, underscoring the importance of updated allergen labeling to facilitate effective prevention plans and anaphylaxis response. This article discusses the prevalence of sesame seed allergy among children in the US and outlines strategies for nurses to understand the assessment, treatment, and education of patients regarding this allergen.

Hypophosphatasia: presentation and response to asfotase alfa.

Hypophosphatasia (HPP) is a rare bone disease with limited scientific evidence on the tolerability and safety of its novel treatment, Asfotase Alfa (AA). We report 7 HPP patients' heterogenous presentations and the significant improvement in various clinical outcomes attained with AA shedding light on this highly effective and safe therapy. INTRODUCTION: Hypophosphatasia (HPP) is a rare inherited metabolic bone disorder characterized by a deficiency in the tissue non-specific alkaline phosphatase (TNSALP) due to loss of function mutation in the ALPL gene. HPP is associated with impaired skeletal mineralization due to elevations in inorganic pyrophosphate and altered phosphate : pyrophosphate ratio. Asfotase alfa (AA) "enzyme replacement" was approved for treatment of HPP in 2015. We present 7 patients with HPP, 5 with pediatric-onset, and 2 with adult-onset, who have been treated with AA and describe the efficacy and safety in these patients. METHODS: 7 patients (4 females, 3 males) aged 19-68 years with HPP were included in this study. Diagnosis of HPP was confirmed by DNA analysis. AA was administered in doses of 6mg/kg/week with a mean follow-up of 6 months (SD= 5). RESULTS: Subjective improvement in muscle strength, muscle pain, walking ability, and walking distance with a reduction in the use of gait aids was seen "with AA in HPP patients." Muscle strength and pain improved by up to 70% from baseline as quantified subjectively by patients. Walking distance improved by up to 100%. Patients also reported improved cognition, mood, and energy levels, with up to 90% improvement in mood and 75% improvement in energy levels. 4 out of 6 patients first noted clinical signs of improvement after 3 months of being on therapy. 1 out of the 7 patients sustained a toe fracture 10 months from being on AA. AA was well-tolerated with injection site reactions being the most reported adverse effect. CONCLUSION: HPP treatment with AA in individuals with both pediatric and adult-onset forms resulted in significant subjective improvement in musculoskeletal and cognitive manifestations in addition to patients' quality of life. The drug was well tolerated in 6 patients. 1 patient discontinued therapy because of minor adverse effects with myalgias.

Refracture following vertebral fragility fracture when bone fragility is not recognized: summarizing findings from comparator arms of randomized clinical trials.

PURPOSE: Since vertebral fragility fractures (VFFs) might increase the risk of subsequent fractures, we evaluated the incidence rate and the refracture risk of subsequent vertebral and non-vertebral fragility fractures (nVFFs) in untreated patients with a previous VFF. METHODS: We systematically searched PubMed, Embase, and Cochrane Library up to February 2022 for randomized clinical trials (RCTs) that analyzed the occurrence of subsequent fractures in untreated patients with prior VFFs. Two authors independently extracted data and appraised the risk of bias in the selected studies. Primary outcomes were subsequent VFFs, while secondary outcomes were further nVFFs. The outcome of refracture within ≥ 2 years after the index fracture was measured as (i) rate, expressed per 100 person-years (PYs), and (ii) risk, expressed in percentage. RESULTS: Forty RCTs met our inclusion criteria, ranging from medium to high quality. Among untreated patients with prior VFFs, the rate of subsequent VFFs and nVFFs was 12 [95% confidence interval (CI) 9-16] and 6 (95% CI 5-8%) per 100 PYs, respectively. The higher the number of previous VFFs, the higher the incidence. Moreover, the risk of VFFs and nVFFs increased within 2 (16.6% and 8%) and 4 years (35.1% and 17.4%) based on the index VFF. CONCLUSION: The highest risk of subsequent VFFs or nVFFs was already detected within 2 years following the initial VFF. Thus, prompt interventions should be designed to improve the detection and treatment of VFFs, aiming to reduce the risk of future FFs and properly implement secondary preventive measures.

Measuring older adults' wellbeing when transitioning into assisted living facilities: a confirmatory factor analysis of the Mueller assessment of transition (MAT).

OBJECTIVES: Older adults' wellbeing during the transition into an assisted living facility (ALF) is not well understood and may influence their wellbeing. The Mueller Assessment of Transition (MAT) was created to measure the impact of transition on older adults' wellbeing. Early developmental testing of the MAT revealed a hypothesized model with two constructs (adjustment strategies and constraints to wellbeing). Therefore, the purpose of this study was to confirm the factor structure of the MAT with a representative sample of older adults transitioning into ALFs. METHODS: In a nationwide sample, 108 older adult participants completed the MAT to measure wellbeing when relocating into ALFs. Confirmatory factor analysis (CFA) assessed the structural validity of the MAT. Internal consistency was evaluated, and chi-square tests of association for regional differences in MAT scores were also conducted. RESULTS: The CFA produced strong fit indices to confirm the hypothesized 2-factor (constraints to wellbeing and adjustment strategies) model of the MAT. Cronbach's alpha for the internal consistency was 0.784 and chi-square test indicated no significant regional differences. CONCLUSION: The MAT was established as a valid and reliable standardized assessment. Implications for using the MAT as a tool to measure older adults' wellbeing and future research are discussed.

Can scuba diving transform the lives of people with physical impairments? A mixed methods study.

PURPOSE: This study aimed to: (1) test and explain the type of experience scuba diving is among people with physical impairments based on the experience-type framework; (2) assess and describe their personality based on the Big Five domains; and (3) identify if personality, years diving, and diving level predict experience-type. METHODS: An explanatory sequential mixed methods design was employed. The quantitative phase used a cross-sectional survey (n = 103). The qualitative phase used follow-up interviews with 15 participants divided into 3 case study groups. Joint displays with meta-inferences integrated the data. RESULTS: Quantitative and qualitative findings concurred on scuba being a transformative experience. 82.52% of survey participants reported scuba as a transformative experience, with no significant differences on experience impact based on impairment category (p = 0.56), impairment onset (p = 0.66), gender (p = 0.08), race/ethnicity (p = 0.51), or age (p = 0.07). Big Five personality domains, years diving, or diving level did not predict experience impact (R2 = 0.14, F(12,90) = 1.304, p = 0.2305). Data strand results differed on salient personality domains. Seven qualitative themes emerged, five on experience-type and two on personality. CONCLUSIONS: We recommend the exploration of scuba diving as a prospective rehabilitation intervention.

Innovative rehabilitation interventions that provide positive experiences and long-term health benefits to people with physical impairments are needed.Participants reported that scuba diving had a positive transformative impact in their lives through positive emotions, peace/relaxation, personal growth, development of skills, social connections, physical and mental healing, and lasting behavioral changes.Reporting scuba diving as a transformative experience was not influenced by the scuba divers' personality domains, diving level, demographic characteristics, or the number of years they had been diving.Authors recommend the consideration and further exploration of scuba diving as a prospective physical and psychosocial rehabilitation intervention.

Navigating the Potential Energy Surface of CdSe Magic-Sized Clusters: Synthesis and Interconversion of Atomically Precise Nanocrystal Polymorphs.

Magic-sized clusters (MSCs) are kinetically stable, atomically precise intermediates along the quantum dot (QD) reaction potential energy surface. Literature precedent establishes two classes of cadmium selenide MSCs with QD-like inorganic cores: one class is proposed to be cation-rich with a zincblende crystal structure, while the other is proposed to be stoichiometric with a "wurtzite-like" core. However, the wide range of synthetic protocols used to access MSCs has made direct comparisons of their structure and surface chemistry difficult. Furthermore, the physical and chemical relationships between MSC polymorphs are yet to be established. Here, we demonstrate that both cation-rich and stoichiometric CdSe MSCs can be synthesized from identical reagents and can be interconverted through the addition of either excess cadmium or selenium precursor. The structural and compositional differences between these two polymorphs are contrasted using a combination of 1H NMR spectroscopy, X-ray diffraction (XRD), pair distribution function (PDF) analysis, inductively coupled plasma optical emission spectroscopy, and UV-vis transient absorption spectroscopy. The subsequent polymorph interconversion reactions are monitored by UV-vis absorption spectroscopy, with evidence for an altered cluster atomic structure observed by powder XRD and PDF analysis. This work helps to simplify the complex picture of the CdSe nanocrystal landscape and provides a method to explore structure-property relationships in colloidal semiconductors through atomically precise synthesis.

Enhanced Charge Transfer from Coinage Metal Doped InP Quantum Dots.

This paper describes coinage-metal-doped InP quantum dots (QDs) as a platform for enhanced electron transfer to molecular acceptors relative to undoped QDs. A synthetic strategy is developed to prepare doped InP/ZnSe QDs. First-principles DFT calculations show that Ag+ and Cu+ dopants localize photoexcited holes while leaving electrons delocalized. This charge carrier wave function modulation is leveraged to enhance electron transfer to molecular acceptors by up to an order of magnitude. Examination of photoluminescence quenching data suggests that larger electron acceptors, such as anthraquinone and methyl viologen, bind to the QD surface in two ways: by direct adsorption to the surface and by adsorption following displacement of a weakly bound surface cation-ligand complex. Reactions with larger acceptors show the greatest increases in electron transfer between doped and undoped quantum dots, while smaller acceptors show smaller enhancements. Specifically, benzoquinone shows the smallest, followed by naphthoquinone and then methyl viologen and anthraquinone. These results demonstrate the benefits of dopant-induced excited-state carrier localization on photoinduced charge transfer and highlight design principles for improved implementation of quantum dots in photoredox catalysis.

Epithelial N-methyl-D-aspartate (NMDA) receptors mediate renal vasodilation by affecting kidney autoregulation.

Background: N-methyl-D-aspartate receptor (NMDAR) are amino acid receptors that are well studied in brain physiology; however, their role in kidney is poorly understood. Nonetheless, NMDAR inhibitors can increase serum K+ and reduce GFR, which suggests they have an important physiological role in the kidney. We hypothesized that NMDARs in the distal nephron induce afferent-arteriole vasodilation through the vasodilator mechanism connecting-tubule-glomerular feedback (CNTGF) that involves ENaC activation. Methods and results: Using a tubule-specific transcriptome database combined with molecular biology and microscopy techniques, we showed kidney expression of NMDAR subunits along the nephron and specifically in ENaC-positive cells. This receptor is expressed in both male and female mice, with higher abundance in females (p=0.02). Microperfusing NMDAR agonists into the connecting tubule induced afferent-arteriole vasodilation (EC50 10.7 vs. 24.5 mM; p<0.001) that was blunted or eliminated with the use of NMDAR blocker MK-801 or with the ENaC inhibitor Benzamil, indicating a dependence on CNTGF of the NMDAR-induced vasodilation. In vivo, we confirmed this CNTGF-associated vasodilation using kidney micropuncture (Stop-flow pressure 37.9±2.6 vs. 28.6±1.9 mmHg, NMDAR agonist vs vehicle; p<0.01). We explored NMDAR and ENaC channel interaction by using mpkCCD cells and split-open connecting tubules. We observed increased amiloride-sensitive current following NMDAR activation that was prevented by MK-801 (1.14 vs. 0.4 µAmp; p=0.03). In split-open tubules, NMDAR activation increased ENaC activity (Npo Vehicle vs. NMDA; p=0.04). Conclusion: NMDARs are expressed along the nephron, including ENaC-positive cells, with higher expression in females. Epithelial NMDAR mediates renal vasodilation through the connecting-tubule-glomerular feedback, by increasing ENaC activity.

Comparison of carbapenem-susceptible and carbapenem-resistant Enterobacterales at nine sites in the USA, 2013-2016: a resource for antimicrobial resistance investigators.

Carbapenem-resistant Enterobacterales (CRE) are an urgent public health threat. Genomic sequencing is an important tool for investigating CRE. Through the Division of Healthcare Quality Promotion Sentinel Surveillance system, we collected CRE and carbapenem-susceptible Enterobacterales (CSE) from nine clinical laboratories in the USA from 2013 to 2016 and analysed both phenotypic and genomic sequencing data for 680 isolates. We describe the molecular epidemiology and antimicrobial susceptibility testing (AST) data of this collection of isolates. We also performed a phenotype-genotype correlation for the carbapenems and evaluated the presence of virulence genes in Klebsiella pneumoniae complex isolates. These AST and genomic sequencing data can be used to compare and contrast CRE and CSE at these sites and serve as a resource for the antimicrobial resistance research community.