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Rozenite (FeSO4·4H2O) is a candidate mineral component of the polyhydrated sulfate deposits on the surface and in the subsurface of Mars. To better understand its behavior at temperature conditions prevailing on the Martian surface and aid its identification in ongoing and future Rover missions, we have carried out a combined experimental and computational study of the mineral’s structure and properties. We collected neutron powder diffraction data at temperatures ranging from 21–290 K, room-temperature synchrotron X-ray data and Raman spectra. Moreover, first-principles calculations of the vibrational properties of rozenite were carried out to aid the interpretation of the Raman spectra. We found, in contrast to a recent Raman spectroscopic study, that there are no phase transitions between 21 and 290 K. We confirm the heavy atom structure reported in the literature (space group P21/n) to be correct and present, for the first time, an unconstrained determination of the H atom positions by means of high-resolution neutron powder diffraction, and report the complete crystal structure at 290 and 21 K. The anisotropy of the thermal expansion of the lattice vectors is αa:αb:αc = 1.00:2.19:1.60 at 285 K. Subsequent analysis of the thermal expansion tensor revealed highly anisotropic behavior as reflected in negative thermal expansion approximately ||〈101〉 and ratios of the tensor eigenvalues of α1:α2:α3 = −1:3.74:5.40 at 285 K. Lastly, we demonstrated how combining Raman spectroscopy and X-ray diffraction of the same sample sealed inside a capillary with complementary first-principles calculations yields accurate reference Raman spectra. This workflow enables the construction of a reliable Raman spectroscopic database for planetary exploration, which will be invaluable to shed light on the geological past as well as in identifying resources for the future colonization of planetary bodies throughout the solar system.

The purpose of this article is to analyze the use of case study research strategy in the field of cadastral studies. The study reviews nineteen doctoral dissertations published in the cadastral research domain. The theoretical background of the case study research strategy is first explained. Major characteristics of the case study research strategy are then identified. Finally, guidelines are provided for the research approach, research design, data collection and data analysis focusing the cadastral case researches. Characteristic of “contextual inclusiveness” of the cadastral system and “how” and “why” questions posed by the researchers on contemporary events have mainly guided researchers to select case study research strategy in cadastral studies. The research design depends largely on the research problem and can be categorized into two groups as; Top-down and Bottom–up design approaches. Theory building prior to data collection process acts as a good foundation for the case studies. High intensity usage of case study research strategy is evident among real world application related issues rather than design focused issues. Multiple-case design approach and multiple data collection methods are popular among the cadastral researchers.

OBJECTIVE: The objective of this study was to investigate variations across hospitals in infection rates and associated costs, the latter reflected in 90-day Medicare payments. Despite high rates and expenditures of healthcare-associated infections associated with durable ventricular assist device implant, few studies have examined inter-hospital variation and associated costs. METHODS: Clinical data on 8688 patients who received primary durable ventricular assist devices from July 2008 to July 2017 from The Society of Thoracic Surgeons Interagency Registry for Mechanically Assisted Circulatory Support (Intermacs) hospitals (n=120) were merged with post-implant 90-day Medicare claims. Terciles of hospital-specific, risk-adjusted infection rates per 100 patient-months were estimated using Intermacs and associated with Medicare payments (among 5440 Medicare beneficiaries). Primary outcomes included infections within 90 days of implant and Medicare payments. RESULTS: There were 3982 infections identified among 27.8% (2,417/8,688) of patients developing an infection. The median (25(th), 75(th) percentile) adjusted incidence of infections (per 100 patient-months) across hospitals was 14.3 (9.3, 19.5) and varied by hospital (range 0.0 – 35.6). Total Medicare payments from implant to 90-days were 9.0% (absolute difference: $13,652) greater in high versus low infection tercile hospitals, p

High prevalences of HIV and other sexually transmitted infections (STIs) have been reported in the current global monkeypox outbreak, which has affected primarily gay, bisexual, and other men who have sex with men (MSM) (1-5). In previous monkeypox outbreaks in Nigeria, concurrent HIV infection was associated with poor monkeypox clinical outcomes (6,7). Monkeypox, HIV, and STI surveillance data from eight U.S. jurisdictions* were matched and analyzed to examine HIV and STI diagnoses among persons with monkeypox and assess differences in monkeypox clinical features according to HIV infection status. Among 1,969 persons with monkeypox during May 17-July 22, 2022, HIV prevalence was 38%, and 41% had received a diagnosis of one or more other reportable STIs in the preceding year. Among persons with monkeypox and diagnosed HIV infection, 94% had received HIV care in the preceding year, and 82% had an HIV viral load of200 copies/mL, indicating HIV viral suppression. Compared with persons without HIV infection, a higher proportion of persons with HIV infection were hospitalized (8% versus 3%). Persons with HIV infection or STIs are disproportionately represented among persons with monkeypox. It is important that public health officials leverage systems for delivering HIV and STI care and prevention to reduce monkeypox incidence in this population. Consideration should be given to prioritizing persons with HIV infection and STIs for vaccination against monkeypox. HIV and STI screening and other recommended preventive care should be routinely offered to persons evaluated for monkeypox, with linkage to HIV care or HIV preexposure prophylaxis (PrEP) as appropriate.

Abstract This study was performed to clarify the transfer and final end of lipofuscin substances that have been formed in cardiomyocytes. The hearts of BALB/c mice were obtained for resin embedding and ultra-thin sectioning. The specimens were observed under a transmission electron microscope, and the images were acquired using an XR401 side-insertion device. Lipofuscin granules are found abundantly in myocardial cells. Cardiomyocytes can excrete lipofuscin granules into the myocardial interstitium using capsule-like protrusions that are formed on the sarcolemma. These granules enter the myocardial interstitium and can be de-aggregated to form membrane-like garbage, which can pass from the myocardial stroma into the lumen of the vessel through its walls. Smaller lipofuscin granules can pass through the walls of the vessels and enter the blood vessel lumen through the capillary endothelial cells. When the extended cytoplasmic end of macrophages and fibroblasts fuse with the endothelial cells, the lipofuscin granules or clumps in the myocardial interstitium are transported to the capillary walls, and then, are released into the lumen of the blood vessel by the endothelial cells. The myocardial tissues of mice may have the ability to eliminate the lipofuscin produced in the cardiomyocytes into the myocardial blood circulation.

Balling defect of the additively manufactured titanium lattice implants easily leads to muscle tissue rejection, which might cause failure of implantation. Electropolishing is widely used in surface polishing of complex components and has potential to deal with the balling defect. However, a clad layer could be formed on the surface of titanium alloy after electropolishing, which may affect the biocompatibility of the metal implants. To manufacture lattice structured β-type Ti-Ni-Ta-Zr (TNTZ) for bio-medical applications, it is necessary to investigate the impact of electropolishing on material biocompatibility. In this study, animal experiments were conducted to investigate the in vivo biocompatibility of the as-printed TNTZ alloy with or without electropolishing; and proteomics technology was used to elaborate the results. The following conclusions were drawn: (a) a 30% oxalic acid electropolishing treatment was effective in solving balling defects, and ~21 nm amorphous clad layer would be formed on the surface of the material after polishing; (b) the electropolished TNTZ suggested decreased cell cytotoxicity and improved blood biocompatibility as compared to as-printed TNTZ; (c) the amorphous clad layer could make a barrier to prevent Ta and Zr ions from penetrating into the muscle tissue, and could form a good tissue regeneration at the implantation site during 4 weeks, indicating that the electropolished TNTZ has the potential as implants; and (d) the cells attached to the electropolished TNTZ showed higher antioxidant capacity but less proliferation than attached to as-printed TNTZ. Graphical Abstract

Nearly 95% of Alzheimer's disease (AD) occurs sporadically without genetic linkage. Aging, hypertension, high cholesterol content, and diabetes are known nongenomic risk factors of AD. Aggregation of Aβ peptides is an initial event of AD pathogenesis. Aβ peptides are catabolic products of a type I membrane protein called amyloid precursor protein (APP). Aβ40 is the major product, whereas the 2-residue-longer version, Aβ42, induces amyloid plaque formation in the AD brain. Since cholesterol content is one risk factor for sporadic AD, we aimed to explore whether cholesterol in the membrane affects the structure of the APP transmembrane region, thereby modulating the γ-secretase cutting behavior. Here, we synthesized several peptides containing the APP transmembrane region (sequence 693–726, corresponding to the Aβ22–55 sequence) with one or two Cys mutations for spin labeling. We performed three electron spin resonance experiments to examine the structural changes of the peptides in liposomes composed of dioleoyl phosphatidylcholine and different cholesterol content. Our results show that cholesterol increases membrane thickness by 10% and peptide length accordingly. We identified that the di-glycine region of Aβ36–40 (sequence VGGVV) exhibits the most profound change in response to cholesterol compared with other segments, explaining how the presence of cholesterol affects the γ-secretase cutting site. This study provides spectroscopic evidence showing how cholesterol modulates the structure of the APP transmembrane region in a lipid bilayer.

In the pursuit of more efficient gas turbine engines, components are required to operate for longer times at elevated temperatures. This increased time in service, together with a complex loading regime, can expose the material to environmental attack. This work has demonstrated that the interaction of stress, NaCl and a sulphur-containing environment is critical to cause crack initiation in the early stages of the exposure and accelerated corrosion rates in CMSX-4 at 550°C. The effect of having small concentrations of moisture in the gaseous environment or as water crystallisation in the salt is still to be investigated. A working hypothesis is that the interaction of alkali chlorides with a sulphur-containing atmosphere is the trigger to a self-sustaining cycle where metal chloride formation, vaporisation and oxidation lead to high amounts of hydrogen injection in a rapid manner and, therefore, hydrogen embrittlement.

The purification of light olefins is one of the most important chemical separations globally and consumes large amounts of energy. Porous materials have the capability to improve the efficiency of this process by acting as solid, regenerable adsorbents. However, to develop translational systems, the underlying mechanisms of adsorption in porous materials must be fully understood. Herein, we report the adsorption and dynamic separation of C

Unsupervised statistical determination of optimal allograft ischemic time (IT) on heart transplant outcomes among ABO donor heart types.We identified 36,145 heart transplants (2000-2018) from the United Network for Organ Sharing database. Continuous and categorical variables were analyzed with parametric and nonparametric testing. Determination of IT cutoffs for survival analysis was performed using Contal and O'Quigley univariable method and Vito Muggeo multivariable segmented modeling.Univariable and multivariable IT threshold determination revealed a cutoff at about 3 h. The hourly increase in survival risk with ≥3 h IT is asymmetrically experienced at the early 90 days (hazard ratio [HR] = 1.29, p .001) and up to 1-year time point (HR = 1.16, p .001). Beyond 1 year the risk of prolonged IT is less impactful (HR = 1.04, p = .022). Longer IT was associated with more postoperative complications such as stroke (2.7% vs. 2.3, p = .042), dialysis (11.6% vs. 9.1%, p .001) and death from primary graft dysfunction (1.8% vs. 1.2%, p .001). O blood type donor hearts with IT ≥ 3 h has significantly increased hourly mortality risk at 90 days (HR = 1.27, p .001), 90 days to 1 year (HR = 1.22, p .001) and1 year (HR = 1.05, p = .041). For non-O blood types with ≥3 h IT hourly mortality risk was increased at 90 days (HR = 1.33, p .001), but not at 90 days to 1 year (HR = 1.09, p = .146) nor ≥1 year (HR = 1.08, p = .237).The donor heart IT threshold for survival determined from unbiased statistical modeling occurs at 3 h. With longer preservation times, transplantation with O donor hearts was associated with worse survival.

BACKGROUND AND OBJECTIVES: Congenital syphilis (CS) is increasing in the United States and is associated with intersecting social and structural determinants of health. This study aimed to delineate birthing parent characteristics associated with CS in an adjusted model. METHODS (N = 720): People diagnosed with syphilis during pregnancy from 2017 to 2018 who were interviewed and linked to infants in the California state surveillance system were included (herein, “birthing parents”). Sociodemographic and clinical CS risk factors informed a stepwise multivariable logistic regression model in which the outcome of interest was infants born with CS. CS prevention continuums delineated the proportion of pregnant people with syphilis who completed steps (e.g., prenatal care entry, syphilis testing, treatment) needed to prevent CS; the outcome was delivering an infant without CS. We stratified continuums by homelessness and methamphetamine use to explore differences in CS outcomes. RESULTS: Of 720 birthing parents, 245 (34%) delivered an infant with CS. Although CS was initially associated with homelessness (odds ratio [OR] = 2.5, 95% confidence interval [CI]: 1.6, 4.0) and methamphetamine use (OR = 2.1, 95% CI: 1.4, 3.1), the addition of prenatal care into a final adjusted model attenuated these associations to not significant. In CS prevention continuums, delivering an infant without CS was less likely for people who reported methamphetamine use (p < .001) and/or homelessness (p < .001). However, when examining only those who received prenatal care, statistical differences for these predictors no longer existed. In the final adjusted model the following were associated with CS: no prenatal care (OR = 16.7, 95% CI: 9.2, 30.3) or late prenatal care (OR = 2.9, 95% CI: 1.9, 4.2); early stage of syphilis (OR = 2.6, 95% CI: 1.8, 3.7); living in Central California (OR = 2.1, 95% CI: 1.1, 4.2). CONCLUSIONS AND SCIENTIFIC SIGNIFICANCE: This is the first analysis to explore birthing parent characteristics associated with delivering an infant with CS in an adjusted model. We demonstrate that prenatal care, when accessed, can result in effective CS prevention among people who are unhoused and/or using methamphetamine equally well compared to counterparts without these risk factors.

Functional imaging has been used extensively to identify and validate disease-specific networks as biomarkers in neurodegenerative disorders. It is not known, however, whether the connectivity patterns in these networks differ with disease progression compared to the beneficial adaptations that may also occur over time. To distinguish the 2 responses, we focused on assortativity, the tendency for network connections to link nodes with similar properties. High assortativity is associated with unstable, inefficient flow through the network. Low assortativity, by contrast, involves more diverse connections that are also more robust and efficient. We found that in Parkinson’s disease (PD), network assortativity increased over time. Assoratitivty was high in clinically aggressive genetic variants but was low for genes associated with slow progression. Dopaminergic treatment increased assortativity despite improving motor symptoms, but subthalamic gene therapy, which remodels PD networks, reduced this measure compared to sham surgery. Stereotyped changes in connectivity patterns underlie disease progression and treatment responses in PD networks.

Protein tyrosine phosphatases (PTPs) are an important class of enzymes that modulate essential cellular processes through protein dephosphorylation and are dysregulated in various disease states. There is demand for new compounds that target the active sites of these enzymes, for use as chemical tools to dissect their biological roles or as leads for the development of new therapeutics. In this study, we explore an array of electrophiles and fragment scaffolds to investigate the required chemical parameters for covalent inhibition of tyrosine phosphatases. Our analysis juxtaposes the intrinsic electrophilicity of these compounds with their potency against several classical PTPs, revealing chemotypes that inhibit tyrosine phosphatases while minimizing excessive, potentially non-specific reactivity. We also assess sequence divergence at key residues in PTPs to explain their differential susceptibility to covalent inhibition. We anticipate that our study will inspire new strategies to develop covalent probes and inhibitors for tyrosine phosphatases.

Background Non-schistosomiasis-associated squamous cell carcinoma of the urinary bladder is less common in the Western world. Limited information on its possible paraneoplastic syndromes exists. Leukocytosis tends to commonly be regarded by clinicians as an indication of sepsis, rather than a feature of paraneoplasia, potential surrogate marker for recurrence, and prognostic marker. Accompanying hypercalcemia may be missed entirely. Case presentation A 66-year-old Caucasian man presented with visible painless hematuria and symptomatic hypercalcemia. Investigations revealed a squamous cell carcinoma of the urinary bladder with marked leukocytosis. Hypercalcemia and leukocytosis resolved following radical cystectomy, recurred with nodal recurrence and regressed with radiotherapeutic control. Subsequently, serum leukocyte and calcium assays were included in his follow-up protocol. His survival was 20 months by the time of the report. Conclusion This report highlights hypercalcemia–leukocytosis syndrome as a paraneoplastic manifestation of non-schistosomiasis-associated squamous cell carcinoma to reemphasize the need for clinicians to assay for calcium in the presence of leukocytosis in such patients. Prompt identification and control of the paraneoplastic derangements, with treatment of the cancer recurrence it may connote, is advocated to provide a chance for better long-term outcomes in these patients.

Recent research using Eye Movement analysis with Hidden Markov Models (EMHMM) has reported that in face recognition, participants who look more at the eyes in addition to the face center (the analytic pattern) have better recognition performance than those looking mainly at the face center (the holistic pattern). Here we examined the mechanisms underlying the advantage of the analytic pattern through an Event-Related Potential (ERP) examination with simultaneous recording of EEG and eye movement. Using EMHMM, we identified nose-focused and eyes-focused eye movement patterns from participants. As compared with participants using nose-focused patterns, those with eyes-focused patterns showed increased N170 amplitude, reduced P2 amplitude, increased N250 amplitude, and prolonged P300 latency, suggesting that they may have engaged more in local face processing, perceived faces as less typical, developed richer perceptual memory representations, and engaged more in stimulus evaluation processes. Importantly, optimal face recognition performance was associated with a mixture of nose- and eyes-focused eye movement patterns and an intermediate level of P300 latency. Also, among all behavioral and ERP measures, eye movement pattern uniquely predicted participants’ recognition performance. Further regression analysis showed that eye movement pattern could be predicted by a combination of Tower of London task performance and ERP P2 amplitude. These results suggest that the optimal face recognition performance involves a balance between global and local face processing, and eye movement pattern is a multifaceted measure that reflects individual differences in both executive function and quality of perceptual representation, making it a unique predictor for recognition performance.

The version of this article on this repository is an arXiv preprint (arXiv:2208.14575v2 [physics.ins-det] Mon, 6 Mar 2023 19:46:42 UTC (39,794 KB)) submitted to Elsevier and is not the final, peer reviewed, corrected article. It is made available under a Creative Commons (CC BY 4.0) Attribution License. This article presents a collection of simulation studies using the ECCE detector concept in the context of the EIC's exclusive, diffractive, and tagging physics program, which aims to further explore the rich quark–gluon structure of nucleons and nuclei. To successfully execute the program, ECCE proposed to utilize the detector system close to the beamline to ensure exclusivity and tag ion beam/fragments for a particular reaction of interest. Preliminary studies confirm the proposed technology and design satisfy the requirements. The projected physics impact results are based on the projected detector performance from the simulation at 10 or 100 fb−1 of integrated luminosity. Additionally, insights related to a potential second EIC detector are documented, which could serve as a guidepost for future development. Office of Nuclear Physics in the Office of Science in the Department of Energy, the National Science Foundation, USA, the Los Alamos National Laboratory Directed Research and Development (LDRD), USA 20200022DR, the Natural Sciences and Engineering Research Council of Canada (NSERC), and the UK Research and Innovation Science and Technology Facilities Council; This research used resources from the Compute and Data Environment for Science (CADES) at the Oak Ridge National Laboratory, which is supported by the Office of Science of the U.S. Department of Energy under Contract No. DE-AC05-00OR22725; Brookhaven National Lab and the Thomas Jefferson National Accelerator Facility which are operated under contracts DE-SC0012704 and DE-AC05-06OR23177 respectively.

Additional stratified data

Excel file containing Tables S1 through S13

Women with a history of ductal carcinoma in situ (DCIS) have an elevated risk of a subsequent invasive breast cancer, but there are few established potentially modifiable factors known to lower this risk. Bisphosphonates are a commonly used treatment for patients with osteoporosis and have been shown to lower risks of recurrence and mortality in patients with invasive breast cancer; however, their use has not previously been investigated within the context of DCIS. Utilizing a population-based nested case–control design, we compared 301 cases of women diagnosed with DCIS and a subsequent breast cancer and 587 individually matched controls (on age, DCIS diagnosis year, primary treatment, histology, grade, and disease-free survival time) who were diagnosed with DCIS but never a subsequent breast cancer. Information on recency and duration of bisphosphonate use was ascertained from patient interviews and medical record reviews. Current users of bisphosphonates had a reduced risk of developing an invasive breast cancer compared with never users [OR = 0.50; 95% confidence interval (CI): 0.26–0.99]. Users of bisphosphonates for ≥48 months had a similar reduction in risk (OR = 0.45; 95% CI, 0.24–1.06). This is the first study to document that bisphosphonate use is associated with a lower risk of subsequent invasive breast cancer among women with a history of DCIS. This finding is consistent with the protective effect of bisphosphonates observed in other breast cancer settings. If validated by others, bisphosphonates may be an effective risk-reducing approach with the potential added benefits of its positive impacts on bone health and fracture risk.Significance:This study finds that bisphosphonate use among women with a history of DCIS is associated with lower risk of subsequent invasive breast cancer, providing a potential preventative approach for this high-risk population.

Purpose:Basal-like breast cancer (BLBC) is a particularly aggressive intrinsic molecular subtype of breast cancer that lacks targeted therapies. There is also no clinically useful test to risk stratify patients with BLBC. We hypothesized that a transcriptome-based phenotypic characterization of BLBC tumors and their microenvironments may overcome these challenges.Experimental Design:We conducted a retrospective correlative genomic sequencing study using a matched pairs design with validation in five independent cohorts. The study was conducted on a large population-based prospective cohort of the major molecular subtypes of breast cancer conducted in the greater Seattle-Puget Sound metropolitan area. Cases consisted of women 20–69 years of age first diagnosed with invasive breast cancer identified through the population-based Surveillance Epidemiology and End Results program. Patients for this analysis (n = 949) were identified from the 1,408 patients with stage I–III triple-negative breast cancer [estrogen receptor–negative (ER−), progesterone receptor–negative (PR−), HER2−]. Of the 949 women, 248 developed a recurrence after their initial diagnosis. A matched set of 67 recurrent and nonrecurrent BLBC tumors was subjected to transcriptome sequencing. Through RNA sequencing of the matched sets of recurrent and nonrecurrent BLBC tumors, we aimed to identify prognostic phenotypes.To identify nonredundant and uncorrelated prognostic genes, we used an ensemble of variable selection algorithms, which resulted in a ranking of genes on the basis of their expected utility in classification. Using leave-one-out cross-validation, we trained a random forest classifier on the basis of the top 21 genes (BRAVO-DX). Validations were performed in five independent triple-negative or BLBC cohorts, and biomarker robustness and transferability were demonstrated by employing real-time PCR.Results:We found that cancer cell intrinsic and immunologic phenotypes are independent predictors of recurrence. By simultaneously interrogating the tumor and its microenvironment, we developed a compound risk model that stratified patients into low-, medium-, and high-risk groups, with a 14%/56%/74% chance of recurrence, respectively. Biologically, the primary tumors of patients who developed a recurrence had increased growth factor signaling and stem-like features, while nonrecurrent tumors showed high lymphocyte infiltration with clonal expansion of T and B cells, as well as antitumor polarization of macrophages. We validated our model in five independent cohorts, including three large cohorts, where BRAVO-DX was highly informative in identifying patients with disease recurrence [HR, 6.79 (95% confidence interval (CI), 1.89–24.37); HR, 3.45 (95% CI, 2.41–4.93); and HR, 1.69 (95% CI, 1.17–2.46)]. A smaller gene set focused on the tumor immunophenotype, BRAVO-IMMUNE, was highly prognostic in all five cohorts.Conclusions:Together, these results indicate that phenotypic characteristics of BLBCs and their microenvironment are associated with recurrence-free survival and demonstrate the utility of intrinsic and extrinsic phenotypes as independent prognostic biomarkers in BLBC. Pending further evaluation and validation, our prognostic model has the potential to inform clinical decision-making for patients with BLBC as it identifies those at high risk of rapidly progressing on standard chemotherapy, as well as those who may benefit from alternative first-line therapies.

Supplementary Figures S1 through S10

Alternative polyadenylation (APA) creates distinct transcripts from the same gene by cleaving the pre-mRNA at poly(A) sites that can lie within the 3′ untranslated region (3′UTR), introns, or exons. Most studies focus on APA within the 3′UTR; however, here, we show that CPSF6 insufficiency alters protein levels and causes a developmental syndrome by deregulating APA throughout the transcript. In neonatal humans and zebrafish larvae, CPSF6 insufficiency shifts poly(A) site usage between the 3′UTR and internal sites in a pathway-specific manner. Genes associated with neuronal function undergo mostly intronic APA, reducing their expression, while genes associated with heart and skeletal function mostly undergo 3′UTR APA and are up-regulated. This suggests that, under healthy conditions, cells toggle between internal and 3′UTR APA to modulate protein expression.

Preservation quality of donor hearts is a key determinant of transplant success. Preservation duration beyond 4 hours is associated with primary graft dysfunction (PGD). Given transport time constraints, geographical limitations exist for donor-recipient matching, leading to donor heart underutilization. Here, we showed that metabolic reprogramming through up-regulation of the enzyme immune response gene 1 (IRG1) and its product itaconate improved heart function after prolonged preservation. Irg1 transcript induction was achieved by adding the histone deacetylase (HDAC) inhibitor valproic acid (VPA) to a histidine-tryptophan-ketoglutarate solution used for donor heart preservation. VPA increased acetylated H3K27 occupancy at the IRG1 enhancer and IRG1 transcript expression in human donor hearts. IRG1 converts aconitate to itaconate, which has both anti-inflammatory and antioxidant properties. Accordingly, our studies showed that Irg1 transcript up-regulation by VPA treatment increased nuclear translocation of nuclear factor erythroid 2–related factor 2 (Nrf2) in mice, which was accompanied by increased antioxidant protein expression [hemeoxygenase 1 (HO1) and superoxide dismutase 1 (SOD1)]. Deletion of Irg1 in mice (Irg1 −/− ) negated the antioxidant and cardioprotective effects of VPA. Consistent with itaconate’s ability to inhibit succinate dehydrogenase, VPA treatment of human hearts increased itaconate availability and reduced succinate accumulation during preservation. VPA similarly increased IRG1 expression in pig donor hearts and improved its function in an ex vivo cardiac perfusion system both at the clinical 4-hour preservation threshold and at 10 hours. These results suggest that augmentation of cardioprotective immune-metabolomic pathways may be a promising therapeutic strategy for improving donor heart function in transplantation.

Here we report a new series of hydrolytically stable chemotype heteroaromatic azoline thioethers (HATs) to achieve highly selective, rapid, and efficient covalent labeling of cysteine under physiological conditions. Although the resulting cysteine-azoline conjugate is stable, we highlight traceless decoupling of the conjugate to afford unmodified starting components in response to reducing conditions. We demonstrated that HAT probes reverse the reactivity of nucleophilic cysteine to electrophilic dehydroalanine (Dha) under mild basic conditions. We demonstrated the umpolung capability of HAT probes for the modification of cysteine on peptides and proteins with various nucleophiles. We demonstrated that HAT probes increase the mass sensitivity of the modified peptides and proteins by 100 fold as compared to the classical methods. Finally, we extended the application of HAT probes for specific modification of cysteines in a complex cell lysate mixture.