The Risk of Hepatocellular Carcinoma in Entecavir Versus Tenofovir Treated US Cohort With Chronic Hepatitis B Virus.

The comparative effectiveness of tenofovir (TDF) vs entecavir (ETV) in reducing the risk of hepatocellular carcinoma (HCC) in patients with chronic hepatitis B virus (HBV) remains unclear. Data from a retrospective Korean cohort study published by Choi et al1 initially suggested a lower-than-expected incidence of HCC in patients on long-term TDF. However, additional studies from Korea did not show a statistically significant difference in HCC incidence rate between TDF and ETV groups,2,3 and subsequent studies reported mixed results ranging from no association or a slight advantage for TDF.4 Most of these studies examined Asian patients from Korea, Taiwan, and China.

Effect of HIV and antiretroviral therapy use on body weight changes in a cohort of U.S. veterans living with and without HIV.

OBJECTIVE: People living with HIV have high rates of obesity and obesity-related comorbidities. Our study sought to evaluate weight trajectory in a retrospective cohort of people living with HIV and matched HIV-negative veterans (controls) and to evaluate risk factors for weight gain. METHODS: This was a retrospective database analysis of data extracted from the VA Corporate Data Warehouse that included people living with HIV (n = 22 421) and age-matched HIV-negative controls (n = 63 072). The main outcomes were baseline body weight and weight change from baseline at 1, 2, and 5 years after diagnosis (baseline visit for controls). RESULTS: Body weight at baseline was lower in people living with HIV than in controls. People living with HIV on antiretroviral therapy (ART) gained more weight than did controls. In a sub-analysis of ART-exposed people living with HIV, age >50 years, African American race, body mass index (BMI) <25, CD4 ≤200, and HIV diagnosis year after 2000 were associated with more weight gain at year 1. Nucleoside reverse transcriptase inhibitors (NRTI) plus non-NRTIs (NNRTIs) were associated with less weight gain than NRTIs plus protease inhibitors, NRTIs plus integrase inhibitors, or NRTIs plus other agents at year 1. CONCLUSIONS: Among US veterans, those living with HIV had lower rates of obesity than age-matched HIV-negative controls; however, primarily in the first 2 years after starting ART, people living with HIV gained more weight than did controls.

Documented Adverse Drug Reactions and Discontinuation of Angiotensin-Converting Enzyme Inhibitors and Angiotensin Receptor Blockers in Chronic Kidney Disease.

INTRODUCTION: Angiotensin-converting enzyme inhibitors (ACEis) and angiotensin receptor blockers (ARBs) are frequently discontinued in patients with chronic kidney disease (CKD). Documented adverse drug reactions (ADRs) in medical records may provide insight into the reasons for treatment discontinuation. METHODS: In this retrospective cohort of US veterans from 2005 to 2019, we identified individuals with CKD and a current prescription for an ACEi or ARB (current user group) or a discontinued prescription within the preceding 5 years (discontinued group). Documented ADRs in structured datasets associated with an ACEi or ARB were categorized into 17 pre-specified groups. Logistic regression assessed associations of documented ADRs with treatment discontinuation. RESULTS: There were 882,441 (73.0%) individuals in the current user group and 326,794 (27.0%) in the discontinued group. There were 26,434 documented ADRs, with at least one documented ADR in 7,520 (0.9%) current users and 9,569 (2.9%) of the discontinued group. ADR presence was associated with treatment discontinuation, aOR 4.16 (95% CI: 4.03, 4.29). The most common documented ADRs were cough (37.3%), angioedema (14.2%), and allergic reaction (10.4%). ADRs related to angioedema (aOR 3.81, 95% CI: 3.47, 4.17), hyperkalemia (aOR 2.03, 95% CI: 1.84, 2.24), peripheral edema (aOR 1.53, 95% CI: 1.33, 1.77), or acute kidney injury (aOR 1.32, 95% CI: 1.15, 1.51) were associated with treatment discontinuation. CONCLUSION: ADRs leading to drug discontinuation were infrequently documented. ADR types were differentially associated with treatment discontinuation. An understanding of which ADRs lead to treatment discontinuation provides an opportunity to address them at a healthcare system level.

Stacking Faults Assist Lithium-Ion Conduction in a Halide-Based Superionic Conductor.

In the pursuit of urgently needed, energy dense solid-state batteries for electric vehicle and portable electronics applications, halide solid electrolytes offer a promising path forward with exceptional compatibility against high-voltage oxide electrodes, tunable ionic conductivities, and facile processing. For this family of compounds, synthesis protocols strongly affect cation site disorder and modulate Li+ mobility. In this work, we reveal the presence of a high concentration of stacking faults in the superionic conductor Li3YCl6 and demonstrate a method of controlling its Li+ conductivity by tuning the defect concentration with synthesis and heat treatments at select temperatures. Leveraging complementary insights from variable temperature synchrotron X-ray diffraction, neutron diffraction, cryogenic transmission electron microscopy, solid-state nuclear magnetic resonance, density functional theory, and electrochemical impedance spectroscopy, we identify the nature of planar defects and the role of nonstoichiometry in lowering Li+ migration barriers and increasing Li site connectivity in mechanochemically synthesized Li3YCl6. We harness paramagnetic relaxation enhancement to enable 89Y solid-state NMR and directly contrast the Y cation site disorder resulting from different preparation methods, demonstrating a potent tool for other researchers studying Y-containing compositions. With heat treatments at temperatures as low as 333 K (60 °C), we decrease the concentration of planar defects, demonstrating a simple method for tuning the Li+ conductivity. Findings from this work are expected to be generalizable to other halide solid electrolyte candidates and provide an improved understanding of defect-enabled Li+ conduction in this class of Li-ion conductors.

Risk and incidence of head and neck cancers in veterans living with HIV and matched HIV-negative veterans.

BACKGROUND: Persons living with HIV/AIDS have a higher incidence of virus-related and tobacco/alcohol-related cancers. This study is the first to estimate the effect of HIV versus HIV-negative veterans on the risk of head and neck squamous cell carcinoma incidence in a large retrospective cohort study. METHODS: The authors constructed a retrospective cohort study using patient data from 1999 to 2016 from the National Veterans Administration Corporate Data Warehouse and the VA Central Cancer Registry. This cohort study included 45,052 veterans living with HIV/AIDS and 162,486 HIV-negative patients matched by age, sex, and index visit (i.e., HIV diagnosis date or clinic visit date). The age-standardized incidence rates and estimated adjusted hazard ratios were calculated with a Cox proportional hazards regression for oropharyngeal and nonoropharyngeal head and neck cancer squamous cell carcinoma (HNSCC). The authors also abstracted human papillomavirus (HPV) status from oropharyngeal HNSCC diagnosed after 2010. RESULTS: Veterans living with HIV/AIDS (VLWH) have 1.71 (95% confidence interval [CI], 1.36, 2.14) times the risk of oropharyngeal cancer and 2.06 (95% CI, 1.76, 2.42) times the hazard of nonoropharyngeal cancer compared with HIV-negative veterans. VLWH with oropharyngeal squamous cell carcinoma (OPSCC) were more likely to be HPV-positive (N = 30 [81.1%]) than the HIV-negative veterans with OPSCC (N = 50 [67.6%]), although this difference was not significant (p = .135). For nonoropharyngeal cancer, the increased risk of oral cavity cancer among VLWH drove the increased risk. CONCLUSIONS: The study results suggest that HIV may play a role in virally mediated and nonvirally mediated HNSCC. As the HIV prevalence rises in the United States due to better survival and the incidence of HPV-positive oropharyngeal HNSCC increases, the interaction between HPV and HIV becomes increasingly relevant.

Validation of the Updated Hepatocellular Carcinoma Early Detection Screening Algorithm in a Community-Based Cohort of Patients With Cirrhosis of Multiple Etiologies.

BACKGROUND & AIMS: The Hepatocellular carcinoma (HCC) Early detection Screening (HES) algorithm has been proposed to improve the performance of the serum alpha-fetoprotein (AFP) test in surveillance for HCC. The HES algorithm incorporates data on age, level of alanine aminotransferase, platelet count, and rate of AFP change to increase likelihood of earlier detection and thereby reduce HCC-related mortality. We updated the HES algorithm to include etiology of cirrhosis and validated it in a community-based cohort. METHODS: We collected data from the Veterans Health Administration, from 2010 through 2015, on etiologies for HCC, including hepatitis C, hepatitis B, alcoholic liver disease, and non-alcoholic fatty liver disease. We used these data to update the HES algorithm and tested its accuracy using data from patients with cirrhosis in the Kaiser Permanente Northern California healthcare system (validation cohort). RESULTS: Among the 7432 patients with cirrhosis in the validation cohort, 1102 were diagnosed with HCC during a median follow-up time of 3.21 years; 709 patients had early-stage HCC. The HES algorithm identified patients who would receive a diagnosis of early-stage HCC within the next 6 months with 51.20% sensitivity and 90.00% specificity, compared with 46.02% sensitivity for the AFP test alone (5.18% absolute improvement; P = .0015). In HCC screening, a positive result from HES or AFP test leads to follow-up evaluation with more sensitive imaging methods. The number of early-stage HCC cases detected per 1000 imaging analyses were 136.46 with the HES algorithm vs 118.01 with the AFP test alone (P < .0005). The HES algorithm identified 56.00% of patients with HCC in the 6 months before their diagnosis despite no detection of nodules by surveillance ultrasound; the AFP test identified only 50.00% of these patients. CONCLUSIONS: We validated the HES algorithm using data from a diverse community-based cohort of patients with cirrhosis. The algorithm offers a modest but useful advantage over the AFP test alone in detection of early-stage HCC with virtually no added cost.

Post-Traumatic Stress Disorder is Associated with further Increased Parkinson's Disease Risk in Veterans with Traumatic Brain Injury.

OBJECTIVE: Determining if traumatic brain injury (TBI) and post-traumatic stress disorder (PTSD) are risk factors for Parkinson's disease (PD). This constitutes a research priority for the Veterans Administration (VA) with implications for screening policy and prevention. METHODS: Population-based, matched case-control study among veterans using VA health care facilities from October 1, 1999, to September 30, 2013. We identified 176,871 PD cases and 707,484 randomly selected PD-free matched controls. PD, TBI, and PTSD were ascertained by validated International Classification of Disease 9th revision (ICD)-9 code-based algorithms. We examined the association between both risk factors and PD using race-adjusted conditional logistic regression. RESULTS: The overall study cohort prevalence for TBImild , TBInon-mild , and PTSD was 0.65%, 0.69%, and 5.5%, respectively. Both TBI and PTSD were significantly associated with PD in single-risk factor race-adjusted analyses (conditional odds ratio [cOR] = 2.99; 95% confidence interval [CI]: 2.69-3.32), 3.82 (95% CI: 3.67-3.97), and 2.71 (95% CI: 2.66-2.77) for TBImild , TBInon-mild , and PTSD, respectively). There was suggestive positive interaction observed with comorbid PTSD/TBI in dual-risk factor analyses, with significant 2.69-fold and 3.70-fold excess relative PD risk in veterans with TBImild and TBInon-mild versus those without TBI when PTSD was present versus 2.17-fold and 2.80-fold excess risk when PTSD was absent. INTERPRETATION: Our study was the first to demonstrate that both TBI and PTSD are independently associated with increased relative PD risk in a diverse nationwide cohort of military service veterans, and the first to suggest a potential modest synergistic excess risk in those with comorbid TBI/PTSD. Longitudinal research is needed to confirm these suggestive findings. ANN NEUROL 2020 ANN NEUROL 2020;88:33-41.

Comparative Effectiveness of Risk-adjusted Cumulative Sum and Periodic Evaluation for Monitoring Hospital Perioperative Mortality.

BACKGROUND: National surgical quality improvement (QI) programs use periodic, risk-adjusted evaluation to identify hospitals with higher than expected perioperative mortality. Rapid, accurate identification of poorly performing hospitals is critical for avoiding potentially preventable mortality and represents an opportunity to enhance QI efforts. METHODS: Hospital-level analysis using Veterans Affairs (VA) Surgical Quality Improvement Program data (2011-2016) to compare identification of hospitals with excess, risk-adjusted 30-day mortality using observed-to-expected (O-E) ratios (ie, current gold standard) and cumulative sum (CUSUM) with V-mask. Various V-mask slopes and radii were evaluated-slope of 2.5 and radius of 1.0 was used as the base case. RESULTS: Hospitals identified by CUSUM and quarterly O-E were identified midway into a quarter [median 47 days; interquartile range (IQR): 24-61 days before quarter end] translating to a median of 129 (IQR: 60-187) surgical cases and 368 (IQR: 145-681) postoperative inpatient days occurring after a CUSUM signal, but before the quarter end. At hospitals identified by CUSUM but not O-E, a median of 2 deaths within a median of 5 days triggered a signal. In some cases, these clusters extended beyond CUSUM identification date with as many as 8 deaths undetected using O-E. Sensitivity and negative predictive values for CUSUM relative to O-E were 71.9% (95% confidence interval: 66.2%-77.1%) and 95.5% (94.4%-96.4%), respectively. CONCLUSIONS: CUSUM evaluation identifies hospitals with clusters of mortality in excess of expected more rapidly than periodic analysis. CUSUM represents an analytic tool national QI programs could utilize to provide participating hospitals with data that could facilitate more proactive implementation of local interventions to help reduce potentially avoidable perioperative mortality.

The association between protease inhibitors and anal cancer outcomes in veterans living with HIV treated with definitive chemoradiation: a retrospective study.

BACKGROUND: The incidence of anal squamous cell carcinoma has been increasing, particularly in people living with HIV (PLWH). There is concern that radiosensitizing drugs, such as protease inhibitors, commonly used in the management of HIV, may increase toxicities in patients undergoing chemoradiation. This study examines treatment outcomes and toxicities in PLWH managed with and without protease inhibitors who are receiving chemoradiation for anal cancer. METHODS: Patient demographic, HIV management, and cancer treatment information were extracted from multiple Veterans Affairs databases. Patients were also manually chart reviewed. Among PLWH undergoing chemoradiation for anal carcinoma, therapy outcomes and toxicities were compared between those treated with and without protease inhibitors at time of cancer treatment. Statistical analysis was performed using chi-square, Cox regression analysis, and logistic regression. RESULTS: A total of 219 PLWH taking anti-retroviral therapy undergoing chemoradiation for anal cancer were identified and included in the final analysis. The use of protease inhibitors was not associated with any survival outcome including colostomy-free survival, progression-free survival, or overall survival (all adjusted hazard ratio p-values> 0.05). Regarding toxicity, protease inhibitor use was not associated with an increased odds of hospitalizations or non-hematologic toxicities; however, protease inhibitor use was associated with increased hospitalizations for hematologic toxicities, including febrile neutropenia (p < 0.01). CONCLUSION: The use of protease inhibitors during chemoradiation for anal carcinoma was not associated with any clinical outcome or increase in non-hematologic toxicity. Their use was associated with increased hospitalizations for hematologic toxicities. Further prospective research is needed to evaluate the safety and efficacy of protease inhibitors for patients undergoing chemoradiation.

Renin-angiotensin system blocker discontinuation and adverse outcomes in chronic kidney disease.

BACKGROUND: Treatment with renin-angiotensin system inhibitors (RASIs), angiotensin-converting enzyme inhibitors (ACEIs) and angiotensin II receptor blockers (ARBs) is the standard of care for those with chronic kidney disease (CKD) and albuminuria. However, ACEI/ARB treatment is often discontinued for various reasons. We investigated the association of ACEI/ARB discontinuation with outcomes among US veterans with non-dialysis-dependent CKD. METHODS: We performed a retrospective cohort study of patients in the Veterans Affairs healthcare system with non-dialysis-dependent CKD who subsequently were started on ACEI/ARB therapy (new user design). Discontinuation events were defined as a gap in ACEI/ARB therapy of ≥14 days and were classified further based on duration (14-30, 31-60, 61-90, 91-180 and >180 days). This was treated as a time-varying risk factor in adjusted Cox proportional hazards models for the outcomes of death and incident end-stage kidney disease (ESKD), which also adjusted for relevant confounders. RESULTS: We identified 141 252 people with CKD and incident ACEI/ARB use who met the inclusion criteria; these were followed for a mean 4.87 years. There were 135 356 discontinuation events, 68 699 deaths and 6152 incident ESKD events. Discontinuation of ACEI/ARB was associated with a higher risk of death [hazard ratio (HR) 2.3, 2.0, 1.99, 1.92 and 1.74 for those discontinued for 14-30, 31-60, 61-90, 91-180 and >180 days, respectively]. Similar associations were noted between ACEI and ARB discontinuation and ESKD (HR 1.64, 1.47, 1.54, 1.65 and 1.59 for those discontinued for 14-30, 31-60, 61-90, 91-180 and >180 days, respectively). CONCLUSIONS: In a cohort of predominantly male veterans with CKD Stages 3 and 4, ACEI/ARB discontinuation was independently associated with an increased risk of subsequent death and ESKD. This may be due to the severity of illness factors that drive the decision to discontinue therapy. Further investigations to determine the causes of discontinuations and to provide an evidence base for discontinuation decisions are needed.

Prevalence, correlates and outcomes of absolute and functional iron deficiency anemia in nondialysis-dependent chronic kidney disease.

BACKGROUND: Anemia is associated with adverse outcomes in those with chronic kidney disease (CKD). We examined the association of absolute and functional iron deficiency anemia (IDA) with adverse outcomes (cardiovascular hospitalization, dialysis and mortality) in those with nondialysis-dependent CKD. METHODS: Nondialysis-dependent CKD patients followed in the US Veterans Administration with hemoglobin level measured within 90 days of the date of the second estimated glomerular filtration rate <60 mL/min/1.73 m2 were included. Logistic regression, multivariate Cox proportional hazards and Poisson regression models adjusted for demographics and comorbidities were used to assess the prevalence and correlates of absolute [transferrin saturation (TSAT) ≤20%, ferritin <100 ng/mL] and functional (TSA T≤20%, ferritin >100-500 ng/mL) IDA and the associations of absolute and functional IDA with mortality, dialysis and cardiovascular hospitalization. RESULTS: Of 933 463 patients with CKD, 20.6% had anemia. Among those with anemia, 23.6% of patients had both TSAT and ferritin level measured, of whom 30% had absolute IDA and 19% had functional IDA. Absolute IDA in CKD was not associated with an increased risk of mortality or dialysis but was associated with a higher risk of 1-year {risk ratio [RR] 1.20 [95% confidence interval (CI) 1.12-1.28]} and 2-year cardiovascular hospitalization [RR 1.11 (95% CI 1.05-1.17)]. CKD patients with functional IDA had a higher risk of mortality [hazard ratio (HR) 1.11 (95% CI 1.07-1.14)] along with a higher risk of 1-year [RR 1.21 (95% CI 1.1-1.30)] and 2-year cardiovascular hospitalization [RR 1.13 (95% CI 1.07-1.21)]. Ferritin >500 ng/mL (treated as a separate category) was only associated with an increased risk of mortality [HR 1.38 (95% CI 1.26-1.51)]. CONCLUSIONS: In a large population of CKD patients with anemia, absolute and functional IDA were associated with various clinical covariates. Functional IDA was associated with an increased risk of mortality and cardiovascular hospitalization, but absolute IDA was associated only with a higher risk of hospitalization.

Relationship Between Perioperative Outcomes Used for Profiling Hospital Noncardiac Surgical Quality.

BACKGROUND: Risk-adjusted morbidity and mortality are commonly used by national surgical quality improvement (QI) programs to measure hospital-level surgical quality. However, the degree of hospital-level correlation between mortality, morbidity, and other perioperative outcomes (like reoperation) collected by contemporary surgical QI programs has not been well-characterized. MATERIALS AND METHODS: Veterans Affairs (VA) Surgical Quality Improvement Program (VASQIP) data (2015-2016) were used to evaluate hospital-level correlation in performance between risk-adjusted 30-d mortality, morbidity, major morbidity, reoperation, and 2 composite outcomes (1- mortality, major morbidity, or reoperation; 2- mortality or major morbidity) after noncardiac surgery. Correlation between outcomes rates was evaluated using Pearson's correlation coefficient. Correlation between hospital risk-adjusted performance rankings was evaluated using Spearman's correlation. RESULTS: Based on a median of 232 [IQR 95-331] quarterly surgical cases abstracted by VASQIP, statistical power for identifying 30-d mortality outlier hospitals was estimated between 3.3% for an observed-to-expected ratio of 1.1 and 45.7% for 3.0. Among 230,247 Veterans who underwent a noncardiac operation at 137 VA hospitals, there were moderate hospital-level correlations between various risk-adjusted outcome rates (highest r = 0.40, mortality and composite 1; lowest r = 0.32, mortality and morbidity). When hospitals were ranked based on performance, there was low-to-moderate correlation between rankings on the various outcomes (highest ρ = 0.47, mortality and composite 1; lowest ρ = 0.37, mortality and major morbidity). CONCLUSIONS: Modest hospital-level correlations between perioperative outcomes suggests it may be difficult to identify high (or low) performing hospitals using a single measure. Additionally, while composites of currently measured outcomes may be an efficient way to improve analytic sample size (relative to evaluations based on any individual outcome), further work is needed to understand whether they provide a more robust and accurate picture of hospital quality or whether evaluating performance across a portfolio of individual measures is most effective for driving QI.

Gout and open-angle glaucoma risk in a veteran population.

PURPOSE: A history of gout, arthritis due to hyperuricemia, has been associated with decreased risk for neurodegenerative diseases such as Parkinson's disease. We performed a population-based case-control study in the US Department of Veterans Affairs (VA) medical centers nationwide to assess if gout or hyperuricemia is similarly associated with the ocular neurodegenerative condition glaucoma. METHODS: We used ICD-9 codes to identify a nationwide cohort of patients examined at VA healthcare eye clinics between 2000 and 2015 with a diagnosis of open-angle glaucoma (OAG) or of glaucoma suspect. We used incidence density matching to choose controls. We used multivariable logistic regression to examine associations between a history of gout and uric acid (UA) levels on relative risk of OAG or glaucoma suspect. RESULTS: There were 1,144,428 OAG or glaucoma suspect cases and 1,144,428 matched controls. Veterans with a history of gout had a small significant decreased risk of OAG compared to controls (ORadjusted(adj) = 0.985, 95% CI: 0.974-0.996). Treated gout was similarly associated with small decreased risk (ORadj = 0.963, 95% CI: 0.950-0.976). A small subset of patients (11.9% of cases and 13.2% of controls) had UA labs available; veterans with the highest median UA levels (> 7.29 mg/dL) did not have statistically significant differences in relative OAG risk (ORadj = 1.014, 95% CI: 0.991-1.036). CONCLUSION: Prospective research in other cohorts is needed to confirm our findings in veterans suggesting a history of gout is associated with a small decreased relative risk of glaucoma.

Association between intensity of statin therapy and mortality in persons with chronic kidney disease.

BACKGROUND: The 2013 American College of Cardiology/American Heart Association lipid guideline recommends statin dosing based on intensity, rather than targeting specific low-density lipoprotein cholesterol (LDL-C) concentrations, among general populations. The 2013 Kidney Disease: Improving Global Outcomes (KDIGO) lipid guideline recommends statins for most adults with chronic kidney disease (CKD), but dose-dependent statin effects in CKD are unclear. METHODS: We performed a retrospective cohort study of US veterans with CKD Stages G3a, G3b or G4, and new, persistent statin use, from 2005 to 2015. We tested the association of intensity of statin therapy [categorized as low (expected LDL-C reduction <30%), medium (30 to <50%) or high (≥50%)] during the initial 1-year exposure period, with all-cause mortality over the subsequent 4 years. We used Cox proportional hazard models to evaluate the association between statin intensity and all-cause mortality, adjusting for demographics, comorbidities and laboratory measurements. RESULTS: Our cohort included 65 292 persons, of whom 40 124 (61.5%) had CKD G3a, 20 183 (30.9%) G3b and 4985 (7.6%) G4. Overall, 4878 (7.5%) used high-intensity, 39 070 (59.8%) used moderate-intensity and 21 344 (32.7%) used low-intensity statins. High-intensity statins were used more in recent years, and among persons diagnosed with atherosclerotic cardiovascular disease. There was no association between statin intensity and mortality in unadjusted or multivariable-adjusted analyses. CONCLUSIONS: There were no significant associations between statin intensity over 1 year of exposure and subsequent mortality among US veterans with CKD. This supports the current KDIGO guideline recommendations to use statins and dosages that have been studied specifically in CKD populations, rather than intensity-based dosing.

An in situ XAS study of high surface-area IrO2 produced by the polymeric precursor synthesis.

Iridium oxide powders with a surface area of more than 1 m2 g-1 (4 m2 g-2 from the H-UPD charge) and iridium-oxide crystallites less than 10 nm across were synthesized by heat treating gels formed from citric acid, ethylene glycol and dihydrogen hexachloroiridate(iv) in air. The characteristics of the resulting material was found to be strongly dependent on the heat-treatment step in the synthesis. A single heat-treatment of the gel resulted in a material with a substantial fraction of elemental iridium metal, i.e. iridium in oxidation state zero (Ir0). Post-synthesis modification of the powder by potential cycling resulted in oxidation peaks consistent with the conversion of the metal phase to iridium oxide. Linear combination of the near-edge part of the X-ray absorption data (X-ray absorption near-edge spectroscopy, XANES) collected in situ during potential cycling and an analysis of the extended X-ray fine-structure (EXAFS) part of the spectrum showed that the overall metal fraction was not significantly affected by the cycling. The oxidation of the metal phase is therefore limited to a thin layer of oxide at the metal surface, and a significant part of the iridium is left inactive. A modification of the heat treatment procedure of the sample resulted in iridium oxide containing only insignificant amounts of elemental iridium metal.

The Detection and Reactivity of Silanols and Silanes Using Hyperpolarized 29 Si Nuclear Magnetic Resonance.

Silanols and silanes are key precursors and intermediates for the synthesis of silicon-based materials. While their characterization and quantification by 29 Si NMR spectroscopy has received significant attention, it is a technique that is limited by the low natural abundance of 29 Si and its low sensitivity. Here, we describe a method using p-H2 to hyperpolarize 29 Si. The observed signal enhancements, approaching 3000-fold at 11.7 T, would take many days of measurement for comparable results under Boltzmann conditions. The resulting signals were exploited to monitor the rapid reaction of tris(tert-butoxy)silanol with triflic anhydride in a T1 -corrected process that allows for rapid quantification. These results demonstrate a novel route to quantify dynamic processes and intermediates in the synthesis of silicon materials.

Intraneural Injection of ATP Stimulates Regeneration of Primary Sensory Axons in the Spinal Cord.

Injury to the peripheral axons of sensory neurons strongly enhances the regeneration of their central axons in the spinal cord. It remains unclear on what molecules that initiate such conditioning effect. Because ATP is released extracellularly by nerve and other tissue injury, we hypothesize that injection of ATP into a peripheral nerve might mimic the stimulatory effect of nerve injury on the regenerative state of the primary sensory neurons. We found that a single injection of 6 µl of 150 µm ATP into female rat sciatic nerve quadrupled the number of axons growing into a lesion epicenter in spinal cord after a concomitant dorsal column transection. A second boost ATP injection 1 week after the first one markedly reinforced the stimulatory effect of a single injection. Single ATP injection increased expression of phospho-STAT3 and GAP43, two markers of regenerative activity, in sensory neurons. Double ATP injections sustained the activation of phospho-STAT3 and GAP43, which may account for the marked axonal growth across the lesion epicenter. Similar studies performed on P2X7 or P2Y2 receptor knock-out mice indicate P2Y2 receptors are involved in the activation of STAT3 after ATP injection or conditioning lesion, whereas P2X7 receptors are not. Injection of ATP at 150 µm caused little Wallerian degeneration and behavioral tests showed no significant long-term adverse effects on sciatic nerve functions. The results in this study reveal possible mechanisms underlying the stimulation of regenerative programs and suggest a practical strategy for stimulating axonal regeneration following spinal cord injury.SIGNIFICANCE STATEMENT Injury of peripheral axons of sensory neurons has been known to strongly enhance the regeneration of their central axons in the spinal cord. In this study, we found that injection of ATP into a peripheral nerve can mimic the effect of peripheral nerve injury and significantly increase the number of sensory axons growing across lesion epicenter in the spinal cord. ATP injection increased expression of several markers for regenerative activity in sensory neurons, including phospho-STAT3 and GAP43. ATP injection did not cause significant long-term adverse effects on the functions of the injected nerve. These results may lead to clinically applicable strategies for enhancing neuronal responses that support regeneration of injured axons.

Risk of Hepatocellular Cancer in Patients With Non-Alcoholic Fatty Liver Disease.

BACKGROUND & AIMS: There are limited data on the risk of hepatocellular cancer (HCC) in patients with non-alcoholic fatty liver disease (NAFLD). We aimed to estimate the risk of incident HCC among patients with NAFLD. METHODS: We conducted a retrospective cohort study from a total of 130 facilities in the Veterans Health Administration. Patients with NAFLD diagnosed between January 1, 2004 and December 31, 2008 were included and followed until HCC diagnosis, death, or December 31, 2015. We also identified a sex- and age-matched control cohort without NAFLD. We ascertained all new HCC cases from the Central Cancer Registry and manual chart reviews. We calculated incidence rates for HCC by NAFLD status, as well as in subgroups of NAFLD patients. We used competing risk models to compare the risk of HCC in patients with NAFLD vs those without NAFLD. We reviewed electronic medical records of all HCC cases that developed in NAFLD patients without cirrhosis. RESULTS: We compared 296,707 NAFLD patients with 296,707 matched controls. During 2,382,289 person-years [PYs] of follow-up, 490 NAFLD patients developed HCC (0.21/1000 PYs). HCC incidence was significantly higher among NAFLD patients vs controls (0.02/1000 PYs; hazard ratio, 7.62; 95% confidence interval, 5.76-10.09). Among patients with NAFLD, those with cirrhosis had the highest annual incidence of HCC (10.6/1000 PYs). Among patients with NAFLD cirrhosis, HCC risk ranged from 1.6 to 23.7 per 1000 PYs based on other demographic characteristics; risk of HCC was the highest in older Hispanics with cirrhosis. In medical record reviews, 20% of NAFLD patients with HCC had no evidence of cirrhosis. CONCLUSIONS: Risk of HCC was higher in NAFLD patients than that observed in general clinical population. Most HCC cases in NAFLD developed in patients with cirrhosis. The absolute risk of HCC was higher than the accepted thresholds for HCC surveillance for most patients with NAFLD cirrhosis.

Validation of the Hepatocellular Carcinoma Early Detection Screening (HES) Algorithm in a Cohort of Veterans With Cirrhosis.

BACKGROUND & AIMS: Early detection of hepatocellular carcinoma (HCC) through surveillance reduces mortality associated with this cancer. Guidelines recommend HCC surveillance every 6 months for patients with cirrhosis, via ultrasonography, with or without measurement of serum level of alpha fetoprotein (AFP). METHODS: We previously developed and internally validated an HCC early detection screening (HES) algorithm that included patient's current level of AFP, rate of AFP change, age, level of alanine aminotransferase, and platelet count in a department of Veterans affairs (VA) cohort with active hepatitis C virus-related cirrhosis. HES score was associated with 3.84% absolute improvement in sensitivity of detection of HCC compared with AFP alone, at 90% specificity, within 6 months prior to diagnosis of this cancer. We externally validated the HES algorithm in a cohort of 38,431 patients with cirrhosis of any etiology evaluated at a VA medical center from 2010 through 2015. RESULTS: A total of 4804 cases of HCC developed during a median follow-up time of 3.12 years. At 90% specificity, the HES algorithm identified patients with HCC with 52.56% sensitivity, compared to 48.13% sensitivity for the AFP assay alone, within 6 months prior to diagnosis; this was an absolute improvement of 4.43% (P < .0005). In HCC screening, a positive result leads to follow-up evaluation by computed tomography or magnetic resonance imaging. We estimated that the number of HCC cases detected per 1000 imaging analyses was 198.57 for the HES algorithm vs 185.52 for the AFP assay alone, or detection of 13 additional cases of HCC (P < .0005). CONCLUSION: We validated the HES algorithm in detection of HCC in patients with cirrhosis of any etiology evaluated at VA medical centers. The algorithm offers a modest but useful advantage over AFP alone in HCC surveillance.

Reaction Monitoring Using SABRE-Hyperpolarized Benchtop (1 T) NMR Spectroscopy.

The conversion of [IrCl(COD)(IMes)] (COD = cis, cis-1,5-cyclooctadiene, IMes = 1,3-bis(2,4,6-trimethyl-phenyl)imidazole-2-ylidene) in the presence of an excess of para-hydrogen ( p-H2) and a substrate (4-aminopyridine (4-AP) or 4-methylpyridine (4-MP)) into [Ir(H)2(IMes)(substrate)3]Cl is monitored by 1H NMR spectroscopy using a benchtop (1 T) spectrometer in conjunction with the p-H2-based hyperpolarization technique signal amplification by reversible exchange (SABRE). A series of single-shot 1H NMR measurements are used to monitor the chemical changes that take place in solution through the lifetime of the hyperpolarized response. Non-hyperpolarized high-field 1H NMR control measurements were also undertaken to confirm that the observed time-dependent changes relate directly to the underlying chemical evolution. The formation of [Ir(H)2(IMes)(substrate)3]Cl is further linked to the hydrogen isotope exchange (HIE) reaction, which leads to the incorporation of deuterium into the ortho positions of 4-AP, where the source of deuterium is the solvent, methanol- d4. Comparable reaction monitoring results are achieved at both high-field (9.4 T) and low-field (1 T). It is notable that the low sensitivity of the benchtop (1 T) NMR enables the use of protio solvents, which when used here allows the effects of catalyst formation and substrate deuteration to be separated. Collectively, these methods illustrate how low-cost low-field NMR measurements provide unique insight into a complex catalytic process through a combination of hyperpolarization and relaxation data.