From Mott insulator to ferromagnetic metal: a pressure study of Ca2_{2}RuO4_{4}

We show that the pressure-temperature phase diagram of the Mott insulator Ca$_{2}$RuO$_{4}$ features a metal-insulator transition at 0.5GPa: at 300K from paramagnetic insulator to paramagnetic quasi-two-dimensional metal; at $T \leq$ 12K from antiferromagnetic insulator to ferromagnetic, highly anisotropic, three-dimensional metal. % We compare the metallic state to that of the structurally related p-wave superconductor Sr$_{2}$RuO$_{4}$, and discuss the importance of structural distortions, which are expected to couple strongly to pressure.Comment: 4 pages, 4figure

Utilization and Outcomes of Single and Dual Kidney Transplants from Older Deceased Donors in the United Kingdom

BACKGROUND AND OBJECTIVES: Kidneys from elderly deceased donors are often discarded after procurement if the expected outcomes from single kidney transplantation are considered unacceptable. An alternative is to consider them for dual kidney transplantation. We aimed to examine the utilization of kidneys from donors aged ≥60 years in the United Kingdom and compare clinical outcomes of dual versus single kidney transplant recipients. DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS: Data from the United Kingdom Transplant Registry from 2005 to 2017 were analyzed. We examined utilization rates of kidneys retrieved from deceased donors aged ≥60 years, and 5-year patient and death-censored graft survival of recipients of dual and single kidney transplants. Secondary outcomes included eGFR. Multivariable analyses and propensity score analysis were used to correct for differences between the groups. RESULTS: During the study period, 7841 kidneys were procured from deceased donors aged ≥60 years, of which 1338 (17%) were discarded; 356 dual and 5032 single kidneys were transplanted. Donors of dual transplants were older (median, 73 versus 66 years; P<0.001) and had higher United States Kidney Donor Risk Indices (2.48 versus 1.98; P<0.001). Recipients of dual transplants were also older (64 versus 61 years; P<0.001) and had less favorable human leukocyte antigen matching (P<0.001). After adjusting for confounders, dual and single transplants had similar 5-year graft survival (hazard ratio, 0.81; 95% CI, 0.59 to 1.12). No difference in patient survival was demonstrated. Similar findings were observed in a matched cohort with a propensity score analysis method. Median 12-month eGFR was significantly higher in the dual kidney transplant group (40 versus 36 ml/min per 1.73 m(2); P<0.001). CONCLUSIONS: Recipients of kidneys from donors aged ≥60 years have similar 5-year graft survival and better graft function at 12 months with dual compared with single deceased donor kidney transplants

Significant benefits of AIP testing and clinical screening in familial isolated and young-onset pituitary tumors

Context Germline mutations in the aryl hydrocarbon receptor-interacting protein (AIP) gene are responsible for a subset of familial isolated pituitary adenoma (FIPA) cases and sporadic pituitary neuroendocrine tumors (PitNETs). Objective To compare prospectively diagnosed AIP mutation-positive (AIPmut) PitNET patients with clinically presenting patients and to compare the clinical characteristics of AIPmut and AIPneg PitNET patients. Design 12-year prospective, observational study. Participants & Setting We studied probands and family members of FIPA kindreds and sporadic patients with disease onset ≤18 years or macroadenomas with onset ≤30 years (n = 1477). This was a collaborative study conducted at referral centers for pituitary diseases. Interventions & Outcome AIP testing and clinical screening for pituitary disease. Comparison of characteristics of prospectively diagnosed (n = 22) vs clinically presenting AIPmut PitNET patients (n = 145), and AIPmut (n = 167) vs AIPneg PitNET patients (n = 1310). Results Prospectively diagnosed AIPmut PitNET patients had smaller lesions with less suprasellar extension or cavernous sinus invasion and required fewer treatments with fewer operations and no radiotherapy compared with clinically presenting cases; there were fewer cases with active disease and hypopituitarism at last follow-up. When comparing AIPmut and AIPneg cases, AIPmut patients were more often males, younger, more often had GH excess, pituitary apoplexy, suprasellar extension, and more patients required multimodal therapy, including radiotherapy. AIPmut patients (n = 136) with GH excess were taller than AIPneg counterparts (n = 650). Conclusions Prospectively diagnosed AIPmut patients show better outcomes than clinically presenting cases, demonstrating the benefits of genetic and clinical screening. AIP-related pituitary disease has a wide spectrum ranging from aggressively growing lesions to stable or indolent disease course

Impact of opioid-free analgesia on pain severity and patient satisfaction after discharge from surgery: multispecialty, prospective cohort study in 25 countries

Background: Balancing opioid stewardship and the need for adequate analgesia following discharge after surgery is challenging. This study aimed to compare the outcomes for patients discharged with opioid versus opioid-free analgesia after common surgical procedures.Methods: This international, multicentre, prospective cohort study collected data from patients undergoing common acute and elective general surgical, urological, gynaecological, and orthopaedic procedures. The primary outcomes were patient-reported time in severe pain measured on a numerical analogue scale from 0 to 100% and patient-reported satisfaction with pain relief during the first week following discharge. Data were collected by in-hospital chart review and patient telephone interview 1 week after discharge.Results: The study recruited 4273 patients from 144 centres in 25 countries; 1311 patients (30.7%) were prescribed opioid analgesia at discharge. Patients reported being in severe pain for 10 (i.q.r. 1-30)% of the first week after discharge and rated satisfaction with analgesia as 90 (i.q.r. 80-100) of 100. After adjustment for confounders, opioid analgesia on discharge was independently associated with increased pain severity (risk ratio 1.52, 95% c.i. 1.31 to 1.76; P &lt; 0.001) and re-presentation to healthcare providers owing to side-effects of medication (OR 2.38, 95% c.i. 1.36 to 4.17; P = 0.004), but not with satisfaction with analgesia (beta coefficient 0.92, 95% c.i. -1.52 to 3.36; P = 0.468) compared with opioid-free analgesia. Although opioid prescribing varied greatly between high-income and low- and middle-income countries, patient-reported outcomes did not.Conclusion: Opioid analgesia prescription on surgical discharge is associated with a higher risk of re-presentation owing to side-effects of medication and increased patient-reported pain, but not with changes in patient-reported satisfaction. Opioid-free discharge analgesia should be adopted routinely

Does screening for asymptomatic coronary artery disease predict cardiac events in kidney transplant recipients? A propensity score matched analysis.

Screening for asymptomatic coronary artery disease prior to kidney transplantation aims to reduce peri- and postoperative cardiac events. It is uncertain if this is achieved. We investigated whether pre-transplant screening with a stress test or coronary angiogram associates with any difference in major adverse cardiac events (MACE) up to 5 years post-transplantation. We examined a national prospective cohort recruited to the Access to Transplant and Transplant Outcome Measures study who received a kidney transplant between 2011-2017, and linked patient demographics and details of cardiac screening investigations to outcome data extracted from the Hospital Episode Statistics dataset and UK Renal Registry. Propensity score matched groups were analysed using Kaplan-Meier and Cox survival analyses. Overall, 2572 individuals were transplanted in 18 centres; 51% underwent screening. The proportion undergoing screening by centre ranged from 5-100%. The incidence of MACE at 90 days, 1 and 5 years was 0.9%, 2.1% and 9.4% respectively. After propensity score matching based on the presence or absence of screening, 1760 individuals were examined (880 in screened and unscreened groups). There was no statistically significant association between screening and MACE at 90 days (hazard ratio [HR] 0.80, 95% CI 0.31-2.05), 1 year (HR 1.12, 95% CI 0.51–2.47) or 5 years (HR 1.31, 95% CI 0.86-1.99). Age, male sex and history of ischaemic heart disease were associated with MACE. There is no association between screening for asymptomatic coronary artery disease and MACE up to 5 years post-transplant. Practices involving unselected screening of transplant recipients should be reviewedJoh

NO BENEFIT OF INGESTING A LOW-DOSE KETONE MONOESTER SUPPLEMENT ON COGNITIVE PERFORMANCE IN TRAINED FEMALES

BACKGROUND: β-hydroxybutyrate is one of three substrates that the brain can preferentially oxidize for meeting energetic demands. Ketone monoesters (KME) allow for the rapid elevation in circulating β-hydroxybutyrate levels without following a low-carbohydrate diet or prolonged fasting and some past work with KME have shown potential to mitigate cognitive decrements in states of fatigue, but no studies have yet been conducted in a female cohort. METHODS: Following a familiarization session and a baseline session without a mental fatiguing protocol (MF), 12 trained females completed two experimental sessions, consisting of a battery of cognitive tests (psychomotor vigilance test (PVT), task-switching, incongruent flanker) performed before (PRE) and after (POST) MF. In a counter-balanced crossover design, a ketone monoester (KME, ~188 mg·kg-1 body mass) or non-caloric placebo (PLA) were ingested before MF. Markers of cognitive performance (speed and correct responses per second), blood β-hydroxybutyrate, glucose, and lactate, and subjective markers of perceived cognitive load and fatigue were collected at PRE and POST.RESULTS: KME ingestion significantly increased blood β-hydroxybutyrate (P\u3c0.001; ~1.8 mM), decreased glucose (P\u3c0.001; ~0.6 mM), and attenuated a ~34% rise in lactate at POST compared to PLA (P=0.04). MF significantly increased perceived cognitive workload and fatigue for both experimental trials in comparison to the control (P\u3c0.05) but did not impair any of the cognitive variables assessed (all P\u3e0.05). Although ingestion of a KME increased perceptions of cognitive performance compared to PLA (KME, 7.8 vs. PLA, 5.5; P=0.05), no differences were observed between groups for markers of cognition.CONCLUSION: Although changes in blood markers mimic those observed in past KME investigations, compared with PLA, KME ingestion did not affect cognitive performance following a MF protocol in trained females

ACUTE INGESTION OF A KETONE MONOESTER WITH CARBOHYDRATE IMPROVES COGNITIVE MEASURES BUT NOT PERFORMANCE IN TRAINED FEMALES

BACKGROUND: In recent years, the field of sports performance and cognitive enhancement has witnessed a growing interest in the potential benefits offered to athletes with the supplementation of exogenous ketones, specifically the ketone monoester (KME). However, the present literature has examined KME ingestion in male or mixed cohorts, with female research currently underrepresented. Thus, we examined the acute ingestion of a KME with co-ingestion of a carbohydrate (KME+CHO) compared to carbohydrate alone (CHO) on cycling performance and cognitive performance in trained females. METHODS: Using a two condition, placebo-controlled, crossover design, twelve trained females (mean ± SD: age, 23 ± 3 y; height, 1.64 ± 0.08 m; mass, 65.2 ± 12.7 kg) completed a baseline assessment of cognitive performance (psychomotor vigilance testing (PVT), task switching, and incongruent flanker), followed by 6x5-min intervals at 40%, 45%, 50%, 55%, 60%, and 65% of their maximal power output (Wmax) and then a 10-km time trial (TT), concluding with the same assessments of cognitive performance post-exercise. Participants consumed either 375 mg·kg-1 body mass of KME with a 6% CHO solution (1 g·min-1 of exercise) or CHO alone, across 3 boluses (50:25:25). RESULTS: Blood β-hydroxybutyrate concentrations averaged 1.80±0.07 mM and 0.13±0.01 mM during exercise in KME+CHO and CHO, respectively. Blood glucose decreased following drink 1 of KME+CHO (~15%; P=0.01) but not CHO alone, and lactate concentrations were significantly lower in KME+CHO at 50%, 55%, 60%, and -65%Wmax (all P\u3c0.05), compared to CHO. Despite these changes, no differences were found between conditions for TT finishing times (KME+CHO, 29.7±5.7 min; CHO, 29.6±5.7 min; P=0.92). However, only KME+CHO resulted in increases in PVT speed (~4%; P=0.01) and faster reaction times (~14%; P\u3c0.01), and speed (~15%; P\u3c0.01) and correct responses (~13%; P=0.03) in the incongruent flanker during post-testing compared to CHO alone. CONCLUSION: Acute ingestion of a KME+CHO elevated blood β-hydroxybutyrate and simultaneously lowered glucose and lactate across multiple timepoints during exercise compared to CHO alone. Although these changes did not affect physical performance, several markers of cognitive performance were improved by the addition of a KME in trained females

Evolution of Fermi-Liquid Interactions in Sr2RuO4 under Pressure

We have measured the temperature and field dependence of the resistivity of the unconventional superconductor Sr2RuO4 at pressures up to 3.3 GPa. Using the Shubnikov–de Haas effect, we find that the Fermi surface sheet believed to be primarily responsible for superconductivity becomes more twodimensional with increasing pressure, a surprising result that is, however, consistent with a recent model of orbital-dependent superconductivity in this system. Many-body enhancements and the superconducting transition temperature all fall gradually with increasing pressure, contrary to previous suggestions of a ferromagnetic quantum critical point at ∼3 GPa