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Objective: Retrospective study to examine the outcomes of acute kidney injury requiring dialysis (AKI-D) patients that received outpatient hemodialysis as part of continued AKI-D care and explore factors associated with recovery of kidney function and discontinuation of dialysis., Methods: Records of all admissions to Emory Dialysis centers between January 2010 to December 2021 were reviewed to include patients with confirmed diagnosis of AKI-D. Basic demographics, comorbidities, duration of hospitalization and cause of AKI were extracted from hospital records and cross-referenced with the dialysis center electronic health record. Patients were followed starting from the day of the first outpatient hemodialysis up to 180 days. All hemodialysis sessions and laboratory data were analyzed. Logistic regression models were used to examine factors associated with recovery of kidney function, defined as survival free of dialysis., Results: 132 patients were analyzed, corresponding to 12,662 patient-day of outpatient AKI-D care. Among those, 19 (14 %) patients died during the observation period. 54 % of patients were male and 70 % were Black race. Median Age was 64 years (IQR 49-79). 42 patients (32 %) recovered enough kidney function to discontinue dialysis. Median time to kidney recovery was 31 days (IQR: 19-75), and the cumulative probability of kidney recovery at 6 months was 39 %. Patients who discontinued dialysis were younger (58 vs 66 years), had higher estimated glomerular filtration rate (eGFR) at time of admission (69 vs 46 ml/min/1.73m 2 ) to the hospital, and were less likely to have a history of hypertension (61 % vs 82 %). Intra-dialytic hypotension was more common in patients who did not recover kidney function., Conclusions: 39 % of patients with AKI-D recovered kidney function within 180 days of outpatient HD start. The median time to recovery was 31 days. Younger age, higher e-GFR at time of hospital admission, and absence of hypertension were predictors of kidney recovery. Patients who recover kidney function experienced episodes of intradialytic hypotension less frequently., Competing Interests: Declaration of competing interest Author Jason Cobb have no conflicts of interest. Author Javier Neyra have no conflicts of interest. Author Jose Navarrete have no conflicts of interest., (Copyright © 2024. Published by Elsevier Inc.)

Purpose: Increased life expectancy in recent years, together with the downward trend in fertility rates, will accelerate the aging of the Latin American population (Flamini and et al., 2018) [1]. This demographic change represents a problem for pension systems as the economic capacity to finance the retirement of the population could be insufficient in the future. This creates a favorable scenario for new financial products, including reverse mortgages. This study determines, from the supply approach, the potential of reverse mortgages in the main cities of Colombia as a complement to the financing of old age according to the guidelines of Benavides et al. (Benavides Franco et al., Jan. 2021) [2]., Methodology: The following variables were used: housing prices, interest rates, mortality rates, and the consumer price index. The econometric testing simulates the possible paths of these variables, estimates the probability of occurrence of the paths, and calculates the expected losses of bidding banks., Findings: The results show that reverse mortgages are a good complement to Colombia's pension system and confirm the feasibility of implementation at city level. It is recommended that the State stimulate the growth of this market and improve the corresponding regulatory framework., Originality: This study confirms the hypothesis that the reverse mortgages are a good complement to the pension system with city-level data. Specifically, it uses housing prices and mortality records from the main cities of the country (Bogotá, Cali, and Medellín) to capture their idiosyncrasies., Competing Interests: The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (© 2024 The Authors.)

Background: Hyperphosphataemia is a common complication of kidney disease. Current dialysis techniques do not provide enough phosphorus clearance, hence the need to use phosphorus binders. Treatment options include calcium carbonate, calcium acetate, lanthanum carbonate, sevelamer hydrochloride and iron-based binders. Patients receiving peritoneal dialysis (PD) with sustained elevated ferritin levels exceeding 800 ng/mL are at a higher risk of death. We identify PD patients treated with iron-based binders and compare ferritin and risk of iron accumulation to patients treated with non-iron-based binders., Methods: All records of patients receiving PD at Emory dialysis centres until 30 October 2021 were reviewed for phosphorus binders. Basic demographics and laboratory data were time-referenced to the days on treatment with a particular binder. Patients were followed until discontinuation of the phosphorus binder, death, transplant, transfer to another dialysis provider or censoring at 36 months after medication was started., Results: Compared to calcium acetate and sevelamer, ferric citrate utilisation in PD patients resulted in a sustained increase in ferritin. The proportion of patients with a ferritin equal to or greater than 800 ng/dL and transferrin saturation greater than 40% increased over time in patients treated with ferric citrate and was higher during the second and third year of follow-up compared to baseline values and to patients treated with calcium acetate or sevelamer. Two patients (7%) treated with ferric citrate developed clinically significant haemosiderosis., Conclusions: Use of ferric citrated in PD resulted in significant iron accumulation as judged by ferritin levels., Competing Interests: Declaration of conflicting interestsThe author(s) declared no potential conflicts of interest with respect to the research, authorship, and/or publication of this article.

Objective: Patients with diabetes and end-stage kidney disease (ESKD) may experience "burnt-out diabetes," defined as having an HbA1c value <6.5% without antidiabetic therapy for >6 months. We aim to assess glycemic control by continuous glucose monitoring (Dexcom G6 CGM) metrics and glycemic markers in ESKD patients on hemodialysis with burnt-out diabetes., Research Design and Methods: In this pilot prospective study, glycemic control was assessed by continuous glucose monitoring (CGM), HbA1c measures, and glycated albumin and fructosamine measurements in patients with burnt-out diabetes (n = 20) and without a history of diabetes (n = 20)., Results: Patients with burnt-out diabetes had higher CGM-measured daily glucose levels, lower percent time in the range 70-180 mg/dL, higher percent time above range (>250 mg/dL), and longer duration of hyperglycemia >180 mg/dL (hours/day) compared with patients without diabetes (all P < 0.01). HbA1c and fructosamine levels were similar; however, patients with burnt-out diabetes had higher levels of glycated albumin than did patients without diabetes., Conclusions: The use of CGM demonstrated that patients with burnt-out diabetes have significant undiagnosed hyperglycemia. CGM and glycated albumin provide better assessment of glycemic control than do values of HbA1c and fructosamine in patients with ESKD., (© 2024 by the American Diabetes Association.)

Several small Polycyclic Aromatic Hydrocarbons (PAHs) have been identified recently in the Taurus Molecular Cloud (TMC-1) using radio telescope observations. Reproducing the observed abundances of these molecules has been a challenge for astrochemical models. Rapid radiative cooling of PAHs by Recurrent Fluorescence (RF), the emission of optical photons from thermally populated electronically excited states, has been shown to efficiently stabilize small PAHs following ionization, augmenting their resilience in astronomical environments and helping to rationalize their observed high abundances. Here, we use a novel method to experimentally determine the radiative cooling rate of the cation of 1-cyanonaphthalene (C 10 H 7 CN, 1-CNN), the neutral species of which has been identified in TMC-1. Laser-induced dissociation rates and kinetic energy release distributions of 1-CNN cations isolated in a cryogenic electrostatic ion-beam storage ring are analysed to track the time evolution of the vibrational energy distribution of the initially hot ion ensemble as it cools. The measured cooling rate is in good agreement with the previously calculated RF rate coefficient. Improved measurements and models of the RF mechanism are needed to interpret astronomical observations and refine predictions of the stabilities of interstellar PAHs.

Polycyclic aromatic hydrocarbons have widely been conjectured to be ubiquitous in space, as supported by the recent discovery of two isomers of cyanonaphthalene, indene, and 2-cyanoindene in the Taurus molecular cloud-1 using radioastronomy. Here, the photoionization dynamics of 1-cyanonaphthalene (1-CNN) are investigated using synchrotron radiation over the hν = 9.0-19.5 eV range, revealing that prompt autoionization from the plasmon resonance dominates the photophysics for hν = 11.5-16.0 eV. Minimal photo-induced dissociation, whether originating from an excited state impulsive bond rupture or through internal conversion followed by a statistical bond cleavage process, occurs over the microsecond timescale (as limited by the experimental setup). The direct photoionization cross section and photoelectron angular distributions are simulated using an ezDyson model combining Dyson orbitals with Coulomb wave photoejection. When considering these data in conjunction with recent radiative cooling measurements on 1-CNN+, which showed that cations formed with up to 5 eV of internal energy efficiently stabilize through recurrent fluorescence, we conclude that the organic backbone of 1-CNN is resilient to photodestruction by VUV and soft XUV radiation. These dynamics may prove to be a common feature for the survival of small polycyclic aromatic hydrocarbons in space, provided that the cations have a suitable electronic structure to support recurrent fluorescence., (© 2023 Author(s). Published under an exclusive license by AIP Publishing.)

Naphthalene and azulene are isomeric polycyclic aromatic hydrocarbons (PAHs) and are topical in the context of astrochemistry due to the recent discovery of substituted naphthalenes in the Taurus Molecular Cloud-1 (TMC-1). Here, the thermal- and photo-induced isomerization, dissociation, and radiative cooling dynamics of energized (vibrationally hot) naphthalene (Np+) and azulene (Az+) radical cations, occurring over the microsecond to seconds timescale, are investigated using a cryogenic electrostatic ion storage ring, affording "molecular cloud in a box" conditions. Measurement of the cooling dynamics and kinetic energy release distributions for neutrals formed through dissociation, until several seconds after hot ion formation, are consistent with the establishment of a rapid (sub-microsecond) Np+ ⇌ Az+ quasi-equilibrium. Consequently, dissociation by C2H2-elimination proceeds predominantly through common Az+ decomposition pathways. Simulation of the isomerization, dissociation, recurrent fluorescence, and infrared cooling dynamics using a coupled master equation combined with high-level potential energy surface calculations [CCSD(T)/cc-pVTZ], reproduce the trends in the measurements. The data show that radiative cooling via recurrent fluorescence, predominately through the Np+ D0 ← D2 transition, efficiently quenches dissociation for vibrational energies up to ≈1 eV above dissociation thresholds. Our measurements support the suggestion that small cations, such as naphthalene, may be more abundant in space than previously thought. The strategy presented in this work could be extended to fingerprint the cooling dynamics of other PAH ions for which isomerization is predicted to precede dissociation., (© 2023 Author(s). Published under an exclusive license by AIP Publishing.)

We have measured recurrent fluorescence (RF) cooling rates of internally hot tetracene cations, C 18 H 12 + , as functions of their storage times and internal energies in two different electrostatic ion-beam storage rings - the cryogenic ring DESIREE with a circumference of 8.6 meters in Stockholm and the much smaller room temperature ring Mini-Ring in Lyon, which has a circumference of 0.71 meters. The RF rates were measured to be as high as 150 to 1000 s -1 for internal energies in the 7 to 9.4 eV energy range, where we have probed the time evolution of the internal energy distribution with nanosecond laser pulses with a 1 kHz repetition rate. These RF rates are found to be significantly higher than those of previously investigated smaller PAHs such as e.g. anthracene and naphthalene, for which the lowest non-forbidden electronic excited state, the D 2 state, is populated with a smaller probability by inverse internal conversion. Furthermore, the D 2 -D 0 transition rate is smaller for these smaller molecules than for tetracene. The complementary features of the two storage rings allow for RF rate measurements in a broader internal energy range than has been possible before. The smaller sampling period of about 6 μs in Mini-Ring is ideal to study the cooling dynamics of the hotter ions that decay fast, whereas DESIREE with a sampling period of about 60 μs is better suited to study the colder ions that decay on longer timescales ranging up to hundreds of milliseconds. The excellent agreement between the two series of measurements in the region where they overlap demonstrates the complementarity of the two electrostatic ion-beam storage rings.

After decades of searching, astronomers have recently identified specific Polycyclic Aromatic Hydrocarbons (PAHs) in space. Remarkably, the observed abundance of cyanonaphthalene (CNN, C 10 H 7 CN) in the Taurus Molecular Cloud (TMC-1) is six orders of magnitude higher than expected from astrophysical modeling. Here, we report unimolecular dissociation and radiative cooling rate coefficients of the 1-CNN isomer in its cationic form. These results are based on measurements of the time-dependent neutral product emission rate and kinetic energy release distributions produced from an ensemble of internally excited 1-CNN + studied in an environment similar to that in interstellar clouds. We find that Recurrent Fluorescence - radiative relaxation via thermally populated electronic excited states - efficiently stabilizes 1-CNN + , owing to a large enhancement of the electronic transition probability by vibronic coupling. Our results help explain the anomalous abundance of CNN in TMC-1 and challenge the widely accepted picture of rapid destruction of small PAHs in space., (© 2023. The Author(s).)

Time-dependent photodetachment action spectra for the linear hydrocarbon anions C 4 H - and C 6 H - are investigated using the cryogenic Double ElectroStatic Ion Ring ExpEriment. The radiative cooling characteristics of these ions on the millisecond to seconds timescale are characterized by monitoring changes in their spectra as the ions cool by spontaneous infrared (IR) emission. The average cooling rates, extracted using Non-negative Matrix Factorization, are fit with 1/e lifetimes of 19 ± 2 and 3.0 ± 0.2 s for C 4 H - and C 6 H - , respectively. The cooling rates are successfully reproduced using a simple harmonic cascade model of IR emission. The ultraslow radiative cooling dynamics determined in this work provide important data for understanding the thermal cooling properties of linear hydrocarbon anions and for refining models of the formation and destruction mechanisms of these anions in astrochemical environments.

Negative ions are important in many areas of science and technology, e.g., in interstellar chemistry, for accelerator-based radionuclide dating, and in anti-matter research. They are unique quantum systems where electron-correlation effects govern their properties. Atomic anions are loosely bound systems, which with very few exceptions lack optically allowed transitions. This limits prospects for high-resolution spectroscopy, and related negative-ion detection methods. Here, we present a method to measure negative ion binding energies with an order of magnitude higher precision than what has been possible before. By laser-manipulation of quantum-state populations, we are able to strongly reduce the background from photodetachment of excited states using a cryogenic electrostatic ion-beam storage ring where keV ion beams can circulate for up to hours. The method is applicable to negative ions in general and here we report an electron affinity of 1.461 112 972(87) eV for 16 O., (© 2022. The Author(s).)

In this paper, we present an apparatus for studies into the photodetachment process of atomic negative ions. State-selective detection of the residual atom following the initial photodetachment step is achieved by combining resonant laser excitation of the photo-detached atom with electric field ionization. The resonance ionization technique in combination with a co-linear ion-laser beam geometry gives an experimental apparatus that has both high selectivity and sensitivity. In addition to measurements of a single selected partial photodetachment channel, the apparatus also can be used to study a manifold of photodetachment channels in which the residual atom is left in a high-lying Rydberg state and for investigation of the double electron-detachment process. Ion-optical simulations in SIMION are used to illustrate the operation of the apparatus for studying such processes. Successful performance of the apparatus against the simulation is demonstrated by a high resolution study of the photodetachment of cesium, where the sharp s-wave threshold of the photodetachment processes leaving the residual atom in the excited 6p state was investigated.

Background: Rapid fluid removal during hemodialysis has been associated with increased mortality. The limit of ultrafiltration rate (UFR) monitored by the Centers for Medicare & Medicaid Services is 13 ml/kg per hour. It is not clear if the proportion of treatments with high UFR is associated with higher mortality. We examined the association of proportion of dialysis treatments with high UFR and mortality in end stage kidney failure patients receiving hemodialysis., Methods: This was a retrospective study of incident patients initiating hemodialysis between January 1, 2010, and December 31, 2019, at Emory dialysis centers. The proportion of treatments with high UFR (>13 ml/kg per hour) per patient was calculated using data from the initial 3 months of dialysis therapy. Patients were categorized on the basis of quartiles of proportion of dialysis sessions with high UFR. Risk of death and survival probabilities were calculated and compared for all quartiles., Results: Of 1050 patients eligible, the median age was 59 years, 56% were men, and 91% were Black. The median UFR was 6.5 ml/kg per hour, and the proportion of sessions with high UFR was 5%. Thirty-one percent of patients never experienced high UFR. Being a man, younger age, shorter duration of hemodialysis sessions, lower weight, diabetic status, higher albumin, and history of heart failure were associated with a higher proportion of sessions with high UFR. Patients in the higher quartile (26% dialysis with high UFR, average UFR 9.8 ml/kg per hour, median survival of 5.6 years) had a higher risk of death (adjusted hazard ratio 1.54; 95% CI, 1.13 to 2.10) compared with those in the lower quartile (0% dialysis with high UFR, average UFR 4.7 ml/kg per hour, median survival 8.8 years)., Conclusions: Patients on hemodialysis who did not experience frequent episodes of elevated UFR during the first 3 months of their dialysis tenure had a significantly lower risk of death compared with patients with frequent episodes of high UFR., Competing Interests: J. Cobb reports research funding from Vertex and honoraria from Aurinia. All remaining authors have nothing to disclose., (Copyright © 2022 by the American Society of Nephrology.)

Background: End-stage kidney disease patients on dialysis are particularly susceptible to COVID-19 infection due to comorbidities, age, and logistic constraints of dialysis making social distancing difficult. We describe our experience with hospitalized dialysis patients with COVID-19 and factors associated with mortality., Methods: From March 1, 2020, to May 31, 2020, all dialysis patients admitted to 4 Emory Hospitals and tested for COVID-19 were identified. Sociodemographic information and clinical and laboratory data were obtained from the medical record. Death was defined as an in-hospital death or transfer to hospice for end-of-life care. Patients were followed until discharge or death., Results: Sixty-four dialysis patients with COVID-19 were identified. Eighty-four percent were African-American. The median age was 64 years, and 59% were males. Four patients were on peritoneal dialysis, and 60 were on hemodialysis for a median time of 3.8 years, while 31% were obese. Fever (72%), cough (61%), and diarrhea (22%) were the most common symptoms at presentation. Thirty-three percent required admission to intensive care unit, and 23% required mechanical ventilation. The median length of stay was 10 days, while 11 patients (17%) died during hospitalization and 17% were discharged to a temporary rehabilitation facility. Age >65 years (RR 13.7, CI: 1.9-100.7), C-reactive protein >100 mg/dL (RR 8.3, CI: 1.1-60.4), peak D-dimer >3,000 ng/mL (RR 4.3, CI: 1.03-18.2), bilirubin >1 mg/dL (RR 3.9, CI: 1.5-10.4), and history of peripheral vascular disease (RR 3.2, CI: 1.2-9.1) were associated with mortality. Dialysis COVID-19-infected patients were more likely to develop thromboembolic complications than those without COVID-19 (RR 3.7, CI: 1.3-10.1)., Conclusion: In a predominantly African-American population, the mortality of end-stage kidney disease patients admitted with COVID-19 infection was 17%. Age, C-reactive protein, D-dimer, bilirubin, and history of peripheral vascular disease were associated with worse survival., (© 2021 S. Karger AG, Basel.)

This report describes the case of a previously healthy 30-year-old woman who presented with uncontrolled hypertension and renal failure. This case emphasizes the importance of considering renal artery disease. The differential diagnosis for renal artery stenosis is discussed, and the diagnosis and management of Takayasu's arteritis in this patient are highlighted. ( Level of Difficulty: Beginner. )., (© 2020 The Authors.)

Background: The hospital admission and mortality rates of patients with diabetic emergencies, such as diabetic ketoacidosis (DKA) and hyperglycemic hyperosmolar nonketotic syndrome (HHNS), are higher in black patients than in white patients with diabetes. However, there is limited data describing the precipitating events and response to treatment in black patients. Analysis of their clinical characteristics and response to medical therapy is needed to evaluate the impact of programs designed to reduce the development of these acute metabolic complications., Methods: A prospective evaluation was conducted of 144 consecutive patients with DKA and 23 patients with HHNS admitted to a large inner-city hospital between July 1993 and October 1994., Results: In patients previously diagnosed as having diabetes, poor compliance with insulin therapy was the major precipitating cause for DKA (49%) and HHNS (42%). Alcohol or cocaine abuse was a contributing factor for noncompliance and was present in 35% and 13% of patients with DKA and in 44% and 9% of patients with HHNS, respectively. Newly diagnosed diabetes accounted for 17% of patients with DKA and HHNS. Obesity (body mass index > 28 kg/m2 [the weight in kilograms divided by the square of the height in meters]) was present in 29% of patients with DKA and in 17% with HHNS and was most common in patients with DKA who were newly diagnosed as having diabetes (56%). Patients were treated by residents, who used a low-dose insulin protocol with an algorithm for insulin adjustment in 88 of 144 patients with DKA and 14 of 23 patients with HHNS. Although there was no difference in mortality rates or time needed to correct hyperglycemia or ketoacidosis, the use of the protocol significantly reduced the risk of hypoglycemia (5%) compared with patients treated without a protocol (23%) (P < .01)., Conclusions: In urban black patients, poor compliance with insulin therapy was the main precipitating cause of acute metabolic decompensation, and substance abuse was a significant contributing factor for noncompliance. Obesity is common in black patients with DKA; it was present in more than half of those with newly diagnosed diabetes. Improved patient education and better access to medical care might reduce the development of these hyperglycemic emergencies.