Deficiency of the Deubiquitinase UCHL1 Attenuates Pulmonary Arterial Hypertension.

BACKGROUND: The ubiquitin-proteasome system regulates protein degradation and the development of pulmonary arterial hypertension (PAH), but knowledge about the role of deubiquitinating enzymes in this process is limited. UCHL1 (ubiquitin carboxyl-terminal hydrolase 1), a deubiquitinase, has been shown to reduce AKT1 (AKT serine/threonine kinase 1) degradation, resulting in higher levels. Given that AKT1 is pathological in pulmonary hypertension, we hypothesized that UCHL1 deficiency attenuates PAH development by means of reductions in AKT1. METHODS: Tissues from animal pulmonary hypertension models as well as human pulmonary artery endothelial cells from patients with PAH exhibited increased vascular UCHL1 staining and protein expression. Exposure to LDN57444, a UCHL1-specific inhibitor, reduced human pulmonary artery endothelial cell and smooth muscle cell proliferation. Across 3 preclinical PAH models, LDN57444-exposed animals, Uchl1 knockout rats (Uchl1-/-), and conditional Uchl1 knockout mice (Tie2Cre-Uchl1fl/fl) demonstrated reduced right ventricular hypertrophy, right ventricular systolic pressures, and obliterative vascular remodeling. Lungs and pulmonary artery endothelial cells isolated from Uchl1-/- animals exhibited reduced total and activated Akt with increased ubiquitinated Akt levels. UCHL1-silenced human pulmonary artery endothelial cells displayed reduced lysine(K)63-linked and increased K48-linked AKT1 levels. RESULTS: Supporting experimental data, we found that rs9321, a variant in a GC-enriched region of the UCHL1 gene, is associated with reduced methylation (n=5133), increased UCHL1 gene expression in lungs (n=815), and reduced cardiac index in patients (n=796). In addition, Gadd45α (an established demethylating gene) knockout mice (Gadd45α-/-) exhibited reduced lung vascular UCHL1 and AKT1 expression along with attenuated hypoxic pulmonary hypertension. CONCLUSIONS: Our findings suggest that UCHL1 deficiency results in PAH attenuation by means of reduced AKT1, highlighting a novel therapeutic pathway in PAH.

Influence of elevated liver enzyme level on 30-day mortality rates in patients undergoing nonemergency orthopedic surgery.

BACKGROUND: The effect of elevated preoperative liver enzyme levels on postoperative outcomes is a topic of concern to clinicians. This study explored the association between elevated preoperative liver enzyme levels and surgical outcomes in patients undergoing orthopedic surgery. METHODS: Using the American College of Surgeons National Surgical Quality Improvement Program database, we obtained data on adult patients who received nonemergency orthopedic surgery under general anesthesia between 2011 and 2021. RESULTS: We evaluated the data of 477,524 patients, of whom 6.1% (24 197 patients) had elevated preoperative serum glutamic oxaloacetic transaminase (SGOT) levels. An elevated SGOT level was significantly associated with 30-day postoperative mortality (adjusted hazard ratio, 1.62; 95% confidence interval, 1.39 to 1.90). We determined that the mortality rate rose with SGOT levels. The results remained unchanged after propensity score matching. CONCLUSION: Elevated preoperative SGOT levels constitute an independent risk factor for 30-day postoperative mortality and are proportionately associated with the risk of 30-day postoperative mortality.

Plasma Proteomics Identifies B2M as a Regulator of Pulmonary Hypertension in Heart Failure With Preserved Ejection Fraction.

BACKGROUND: Pulmonary hypertension (PH) represents an important phenotype in heart failure with preserved ejection fraction (HFpEF). However, management of PH-HFpEF is challenging because mechanisms involved in the regulation of PH-HFpEF remain unclear. METHODS: We used a mass spectrometry-based comparative plasma proteomics approach as a sensitive and comprehensive hypothesis-generating discovery technique to profile proteins in patients with PH-HFpEF and control subjects. We then validated and investigated the role of one of the identified proteins using in vitro cell cultures, in vivo animal models, and independent cohort of human samples. RESULTS: Plasma proteomics identified high protein abundance levels of B2M (ß2-microglobulin) in patients with PH-HFpEF. Interestingly, both circulating and skeletal muscle levels of B2M were increased in mice with skeletal muscle SIRT3 (sirtuin-3) deficiency or high-fat diet-induced PH-HFpEF. Plasma and muscle biopsies from a validation cohort of PH-HFpEF patients were found to have increased B2M levels, which positively correlated with disease severity, especially pulmonary capillary wedge pressure and right atrial pressure at rest. Not only did the administration of exogenous B2M promote migration/proliferation in pulmonary arterial vascular endothelial cells but it also increased PCNA (proliferating cell nuclear antigen) expression and cell proliferation in pulmonary arterial vascular smooth muscle cells. Finally, B2m deletion improved glucose intolerance, reduced pulmonary vascular remodeling, lowered PH, and attenuated RV hypertrophy in mice with high-fat diet-induced PH-HFpEF. CONCLUSIONS: Patients with PH-HFpEF display higher circulating and skeletal muscle expression levels of B2M, the magnitude of which correlates with disease severity. Our findings also reveal a previously unknown pathogenic role of B2M in the regulation of pulmonary vascular proliferative remodeling and PH-HFpEF. These data suggest that circulating and skeletal muscle B2M can be promising targets for the management of PH-HFpEF.

Skeletal Muscle SIRT3 Deficiency Contributes to Pulmonary Vascular Remodeling in Pulmonary Hypertension Due to Heart Failure With Preserved Ejection Fraction.

BACKGROUND: Pulmonary hypertension (PH) is a major complication linked to adverse outcomes in heart failure with preserved ejection fraction (HFpEF), yet no specific therapies exist for PH associated with HFpEF (PH-HFpEF). We have recently reported on the role of skeletal muscle SIRT3 (sirtuin-3) in modulation of PH-HFpEF, suggesting a novel endocrine signaling pathway for skeletal muscle modulation of pulmonary vascular remodeling. METHODS: Using skeletal muscle-specific Sirt3 knockout mice (Sirt3skm-/-) and mass spectrometry-based comparative secretome analysis, we attempted to define the processes by which skeletal muscle SIRT3 defects affect pulmonary vascular health in PH-HFpEF. RESULTS: Sirt3skm-/- mice exhibited reduced pulmonary vascular density accompanied by pulmonary vascular proliferative remodeling and elevated pulmonary pressures. Comparative analysis of secretome by mass spectrometry revealed elevated secretion levels of LOXL2 (lysyl oxidase homolog 2) in SIRT3-deficient skeletal muscle cells. Elevated circulation and protein expression levels of LOXL2 were also observed in plasma and skeletal muscle of Sirt3skm-/- mice, a rat model of PH-HFpEF, and humans with PH-HFpEF. In addition, expression levels of CNPY2 (canopy fibroblast growth factor signaling regulator 2), a known proliferative and angiogenic factor, were increased in pulmonary artery endothelial cells and pulmonary artery smooth muscle cells of Sirt3skm-/- mice and animal models of PH-HFpEF. CNPY2 levels were also higher in pulmonary artery smooth muscle cells of subjects with obesity compared with nonobese subjects. Moreover, treatment with recombinant LOXL2 protein promoted pulmonary artery endothelial cell migration/proliferation and pulmonary artery smooth muscle cell proliferation through regulation of CNPY2-p53 signaling. Last, skeletal muscle-specific Loxl2 deletion decreased pulmonary artery endothelial cell and pulmonary artery smooth muscle cell expression of CNPY2 and improved pulmonary pressures in mice with high-fat diet-induced PH-HFpEF. CONCLUSIONS: This study demonstrates a systemic pathogenic impact of skeletal muscle SIRT3 deficiency in remote pulmonary vascular remodeling and PH-HFpEF. This study suggests a new endocrine signaling axis that links skeletal muscle health and SIRT3 deficiency to remote CNPY2 regulation in the pulmonary vasculature through myokine LOXL2. Our data also identify skeletal muscle SIRT3, myokine LOXL2, and CNPY2 as potential targets for the treatment of PH-HFpEF.

Effects of Adding Extracorporeal Shockwave Therapy (ESWT) to Platelet-Rich Plasma (PRP) among Patients with Rotator Cuff Partial Tear: A Prospective Randomized Comparative Study.

A rotator cuff tear is a prevalent ailment affecting the shoulder joint. The clinical efficacy of combined therapy remains uncertain for partial rotator cuff tears. In this study, we integrated extracorporeal shockwave therapy (ESWT) with platelet-rich plasma (PRP) injection, juxtaposed with PRP in isolation. Both cohorts exhibited significant improvements in visual analogue scale (VAS), Constant-Murley score (CMS), degrees of forward flexion, abduction, internal rotation, and external rotation, and the sum of range of motion (SROM) over the six-month assessment period. The application of ESWT in conjunction with PRP exhibited notable additional enhancements in both forward flexion (p = 0.033) and abduction (p = 0.015) after one month. Furthermore, a substantial augmentation in the range of shoulder motion (SROM) (p < 0.001) was observed after six months. We employed isobaric tag for relative and absolute quantitation (iTRAQ) to analyze the differential plasma protein expression in serum samples procured from the two groups after one month. The concentrations of S100A8 (p = 0.042) and S100A9 (p = 0.034), known to modulate local inflammation, were both lower in the ESWT + PRP cohort. These findings not only underscore the advantages of combined therapy but also illuminate the associated molecular changes.

Albumin Deficiency Reduces Hepatic Steatosis and Improves Glucose Metabolism in a Mouse Model of Diet-Induced Obesity.

Serum albumin facilitates the transport of free fatty acids (FFAs) from adipose tissue to other organs. It was not known if impeding this process could protect from hepatic steatosis and metabolic dysfunction in obesity. We tested whether albumin knockout (Alb-/-) mice would exhibit a reduction in plasma FFA concentration, reduced hepatic lipid accumulation, and improved glucoregulation as compared to wild-type (WT) mice. Male homozygous albumin knockout mice (Alb-/-) and WT controls were fed a low-fat diet (LFD) or high-fat diet (HFD). Alb-/- mice exhibited a similar body weight gain and body composition as WT on both diets. Despite HFD-induced obesity, Alb-/- mice were protected from various comorbidities. Compared to WT mice on the HFD, Alb-/- exhibited lower plasma FFA levels, lower blood glucose levels during glucose tolerance and insulin tolerance tests, and lower hepatic steatosis and inflammation. Alb-/- mice on HFD also exhibited elevated expression of multiple genes in the liver and adipose tissues, such as peroxisome proliferator-activated receptor α in both tissues, as well as glucose transporter-4 and adiponectin in adipose tissues. The results indicate that albumin's FFA transport function may be involved in the development of hepatic lipid accumulation and dysregulated glucose metabolism in obesity.

Clinical characteristics in new psychoactive substance users: A single center study.

New psychoactive substances (NPS) are emerging illegal substances or synthetic drugs that pose public health threats worldwide. This study was aimed at reporting the clinical characteristics of NPS and classical illicit substances used by patients who presented to the emergency room. We conducted a retrospective cohort study on patients with suspected illicit substance use who visited the emergency department (ED) with the suspicion of illicit substance use. We divided the patients into 4 groups based on the NPS testing results: NPS positive, NPS negative, NPS combined with classical illicit drugs (INPS), and subjects with negative testing results. The majority of patients in all groups were male. The NPS users were significantly younger than those with negative results on toxic testing (26.4 vs 37.5, P = .005 < 0.05). The heart rate of NPS users was significantly faster than that of the group with negative results of toxic testing (111.1 vs 93.5 beats per minute, P = .046). The heartbeats of INPS group were also significantly faster than those with a negative result in toxicology screen (119.6 vs 93.5 beats per minute, P = .024). Those who used classical illicit drugs combined with NPS had significantly higher palpitation than those with negative results of toxic testing (27.3% vs 3.1%, P = .017). Patients who were highly suspicious of NPS use were younger, had tachycardia, felt palpitations, and had fair oxygen saturation compared to patients who were negative for urine toxicity screening.

Single flow diverter to manage multiple intracranial aneurysms in a parent artery.

BACKGROUND: Endovascular coil embolization has become an important method in the management of intracranial aneurysm. However, simultaneously coiling multiple intracranial aneurysms (MIAs) in unilateral parent artery in one-stage may fail or insufficient in geographic difficult aneurysm. Flow diverter (FD) has the potential to manage MIAs with nonamenable to coiling. Herein, we report periprocedural morphologic change and outcomes using single FD to manage unruptured MIAs in a parent artery. METHODS: Over a 3-year period, a total of 63 patients with 126 MIAs successful managed by single FD with complete angiographic follow-up. There were 49 women and 14 men, with ages ranging from 42 to 77 years (mean: 59 years). We retrospectively assessed the clinical data, aneurysm characteristic, angiographic and clinical outcomes of all patients and compared with 171 patients with single aneurysm managed by FD. RESULTS: Sixty-one patients with 118 aneurysms (94%) located in internal carotid artery or middle cerebral artery (n = 4, 3%), two patients with four aneurysms (4%) were found in the basilar artery. The mean aneurysm size was 5.6 mm (range from 1.8 to 38 mm). Mean angiographic follow-up was 14 months. Complete obliteration of aneurysm was achieved in 102 aneurysms (83%), subtotal or partial aneurysm obliteration was demonstrated in 18 aneurysms (15%), unchanged aneurysm morphology in three (2%). Aneurysm morphology synchronized alteration in 55 patients (87%), other eight patients (13%) with 16 aneurysms showed different morphologic alteration in angiographic follow-up. Four patients (6.3%) had intraprocedural ischemic complication. During the follow-up period, 61 patients (97%) were neurologic stable; there was no hemorrhagic or ischemic event. CONCLUSION: Single FD was feasible to treat MIAs in a parent artery with both effective and safe in one-stage management. Most aneurysms synchronized alteration of morphology in a mid-term follow-up. The procedure was almost the same with FD managing single aneurysm, but longer FD is needed in MIAs.

Protective Effects of Higher Exposure to Aspirin and/or Clopidogrel on the Occurrence of Hip Fracture among Diabetic Patients: A Retrospective Cohort Study.

Aspirin and clopidogrel are commonly prescribed alone or together among the type 2 diabetes mellitus (T2DM) patients, and both agents could affect bone metabolism. This study aimed at demonstrating the effects of the dosage and the duration of aspirin and/or clopidogrel alone or together on the occurrence of hip fracture among T2DM patients. We chose the patients newly diagnosed with T2DM and divided them into four subgroups which are under aspirin monotherapy (78,522 patients), clopidogrel monotherapy (12,752 patients), dual therapy (7209 patients), and patients not taking antiplatelet drugs (401,686 patients). We found that only higher dosage (>360 cumulative daily defined dose (cDDD)) and longer duration (≥3 years) of antiplatelet agents could be associated with lower fracture risk. Compared with the subjects taking <1-year dual agents, the risk of hip fracture was 0.38-fold for the patients taking ≥3-year dual agents. Lower dosage (28−179 cDDD) and shorter duration (1~2 years) could even be associated with higher fracture risk. Overall, the best regimen to fend off the hip fracture was the use of aspirin and clopidogrel for ≥3 years.

Elucidating the Clinical Implications and Pathophysiology of Pulmonary Hypertension in Heart Failure With Preserved Ejection Fraction: A Call to Action: A Science Advisory From the American Heart Association.

This science advisory focuses on the need to better understand the epidemiology, pathophysiology, and treatment of pulmonary hypertension in patients with heart failure with preserved ejection fraction. This clinical phenotype is important because it is common, is strongly associated with adverse outcomes, and lacks evidence-based therapies. Our goal is to clarify key knowledge gaps in pulmonary hypertension attributable to heart failure with preserved ejection fraction and to suggest specific, actionable scientific directions for addressing such gaps. Areas in need of additional investigation include refined disease definitions and interpretation of hemodynamics, as well as greater insights into noncardiac contributors to pulmonary hypertension risk, optimized animal models, and further molecular studies in patients with combined precapillary and postcapillary pulmonary hypertension. We highlight translational approaches that may provide important biological insight into pathophysiology and reveal new therapeutic targets. Last, we discuss the current and future landscape of potential therapies for patients with heart failure with preserved ejection fraction and pulmonary vascular dysfunction, including considerations of precision medicine, novel trial design, and device-based therapies, among other considerations. This science advisory provides a synthesis of important knowledge gaps, culminating in a collection of specific research priorities that we argue warrant investment from the scientific community.

Flow diverter manages very small aneurysm of the internal carotid artery.

BACKGROUND: Endovascular aneurysm coiling is a minimally invasive method to manage intracranial aneurysms. However, aneurysm coiling may fail in very small aneurysms (VSAs); thus, flow diverter (FD) is recommended as an alternative in these difficult aneurysms. Herein, we report our experience and outcomes of FD to treat VSA of the internal carotid artery (ICA). METHODS: Over a 3-year period, a total of 70 patients with 87 unruptured VSAs of the ICA were managed by FD. There were 54 men and 16 women, with a mean age of 57 (range, 41-75) years. We retrospectively assessed the clinical data, aneurysm characteristics, and angiographic as well as clinical outcomes of patients treated by FD and compared with larger aneurysms. RESULTS: Fifty aneurysms (58%) were located in the supraclinoid ICA, followed by paraclinoid ICA (n = 31, 36%) and cavernous ICA (n = 6, 7%). Most aneurysms (n = 72, 83%) were between 2 and 3 mm in size. The mean aneurysm size was 2.3 mm (range, 1.5-3 mm). Follow-up angiographic data (mean, 13 months) were available in 54 patients with 68 aneurysms. Successful FD deployment in an ideal position to bride aneurysm was achieved in 86 of 87 aneurysms (99%). Complete obliteration (CO) was achieved in 63 aneurysms (93%). Compared with larger aneurysms (>3 mm), VSAs had the tendency to achieve CO ( p < 0.05) in a midterm follow-up. Two patients (2.8%) had intraprocedural complications, including in-stent thrombosis (n = 1) and distal embolism (n = 1). One patient (1.4%) suffered from mild limb weakness. CONCLUSION: The use of FD to manage VSA was technically feasible, and the procedure was simpler than those of larger aneurysms. FD stenting of VSAs was confirmed to be effective and safe and had higher CO rate than those in larger aneurysms in a midterm angiographic follow-up.

The enterprise's external knowledge acquisition capability and technological diversification: From the perspective of intellectual property strategy.

Enterprises need intellectual property rights to protect their core knowledge, and technological diversification is an important strategic measure for enterprises to improve innovation performance. From the perspective of external resource acquisition, this study explores the mechanism of external knowledge acquisition capability (internal absorptive capability and external relational learning) on firm's technological diversification. It considers the impact of firm's innovation capability and external environmental uncertainty. The survey data of 258 Chinese pharmaceutical companies were obtained through questionnaire surveys, and various theoretical hypotheses were validated using regression analysis methods. The results show that internal absorptive capacity, external relational learning, and their interaction have a significant positive impact on technological diversification; the innovation capacity and the uncertainty of the external environment also affect enterprises' technological diversification.

Impact of COVID-19 on liver.

The incidence of liver injury after coronavirus disease 2019 (COVID-19) infection ranged from 15%-53%. The mechanism includes direct viral cytopathic effect, cytokinesis, and treatment drug-induced liver injury. The symptoms include nausea, vomiting, diarrhea, and loss of appetite. The laboratory results include increased liver enzyme levels, decreased monocyte count, and longer prothrombin time. The most common imaging findings are hepatomegaly on ultrasound, ground-glass opacity on chest computed tomography (CT), and liver hypodensity and pericholecystic fat stranding on abdominal CT. Patients may also have different presentations and poor outcomes of different liver diseases concomitant with COVID-19 infection. Liver function test (LFT) results should be monitored, and all factors known to cause or predispose liver injury should be investigated while managing the patients. The risks of transfer to an intensive care unit, need for mechanical ventilator support, and acute kidney injury is higher in COVID-19 patients with than without abnormal LFTs. Increased mortality and length of hospital stay are both observed.

Genetic Association in the Maintenance of the Mitochondrial Microenvironment and Sperm Capacity.

Sperm motility is one of the major determinants of male fertility. Since sperm need a great deal of energy to support their fast movement by active metabolism, they are thus extremely vulnerable to oxidative damage by the reactive oxygen species (ROS) and other free radicals generated as byproducts in the electron transport chain. The present study is aimed at understanding the impact of a mitochondrial oxidizing/reducing microenvironment in the etiopathology of male infertility. We detected the mitochondrial DNA (mtDNA) 4,977 bp deletion in human sperm. We examined the gene mutation of ATP synthase 6 (ATPase6 m.T8993G) in ATP generation, the gene polymorphisms of uncoupling protein 2 (UCP2, G-866A) in the uncoupling of oxidative phosphorylation, the role of genes such as manganese superoxide dismutase (MnSOD, C47T) and catalase (CAT, C-262T) in the scavenging system in neutralizing reactive oxygen species, and the role of human 8-oxoguanine DNA glycosylase (hOGG1, C1245G) in 8-hydroxy-2'-deoxyguanosine (8-OHdG) repair. We found that the sperm with higher motility were found to have a higher mitochondrial membrane potential and mitochondrial bioenergetics. The genotype frequencies of UCP2 G-866A, MnSOD C47T, and CAT C-262T were found to be significantly different among the fertile subjects, the infertile subjects with more than 50% motility, and the infertile subjects with less than 50% motility. A higher prevalence of the mtDNA 4,977 bp deletion was found in the subjects with impaired sperm motility and fertility. Furthermore, we found that there were significant differences between the occurrences of the mtDNA 4,977 bp deletion and MnSOD (C47T) and hOGG1 (C1245G). In conclusion, the maintenance of the mitochondrial redox microenvironment and genome integrity is an important issue in sperm motility and fertility.

Recent advancements in pulmonary arterial hypertension and right heart failure research: overview of selected abstracts from ATS2020 and emerging COVID-19 research.

Each year the American Thoracic Society (ATS) Conference brings together scientists who conduct basic, translational and clinical research to present on the recent advances in the field of respirology. Due to the Coronavirus Disease of 2019 (COVID-19) pandemic, the ATS2020 Conference was held online in a series of virtual meetings. In this review, we focus on the breakthroughs in pulmonary hypertension research. We have selected 11 of the best basic science abstracts which were presented at the ATS2020 Assembly on Pulmonary Circulation mini-symposium "What's New in Pulmonary Arterial Hypertension (PAH) and Right Ventricular (RV) Signaling: Lessons from the Best Abstracts," reflecting the current state of the art and associated challenges in PH. Particular emphasis is placed on understanding the mechanisms underlying RV failure, the regulation of inflammation, and the novel therapeutic targets that emerged from preclinical research. The pathologic interactions between pulmonary hypertension, right ventricular function and COVID-19 are also discussed.

Relaxin Inhibits Ventricular Arrhythmia and Asystole in Rats With Pulmonary Arterial Hypertension.

Pulmonary arterial hypertension (PAH) leads to right ventricular cardiomyopathy and cardiac dysfunctions where in the clinical setting, cardiac arrest is the likely cause of death, in ~70% of PAH patients. We investigated the cardiac phenotype of PAH hearts and tested the hypothesis that the insulin-like hormone, Relaxin could prevent maladaptive cardiac remodeling and protect against cardiac dysfunctions in a PAH animal model. PAH was induced in rats with sugen (20 mg/kg), hypoxia then normoxia (3-weeks/each); relaxin (RLX = 0, 30 or 400 µg/kg/day, n ≥ 6/group) was delivered subcutaneously (6-weeks) with implanted osmotic mini-pumps. Right ventricle (RV) hemodynamics and Doppler-flow measurements were followed by cardiac isolation, optical mapping, and arrhythmia phenotype. Sugen-hypoxia (SuHx) treated rats developed PAH characterized by higher RV systolic pressures (50 ± 19 vs. 22 ± 5 mmHg), hypertrophy, reduced stroke volume, ventricular fibrillation (VF) (n = 6/11) and bradycardia/arrest (n = 5/11); both cardiac phenotypes were suppressed with dithiothreitol (DTT = 1 mM) (n = 0/2/group) or RLX (low or high dose, n = 0/6/group). PAH hearts developed increased fibrosis that was reversed by RLX-HD, but not RLX-LD. Relaxin decreased Nrf2 and glutathione transferases but not glutathione-reductase. High-dose RLX improved pulmonary arterial compliance (measured by Doppler flow), suppressed VF even after burst-pacing, n = 2/6). Relaxin suppressed VF and asystole through electrical remodeling and by reversing thiol oxidative stress. For the first time, we showed two cardiac phenotypes in PAH animals and their prevention by RLX. Relaxin may modulate maladaptive cardiac remodeling in PAH and protect against arrhythmia and cardiac arrest.

Benchmarking of eight recurrent neural network variants for breath phase and adventitious sound detection on a self-developed open-access lung sound database-HF_Lung_V1.

A reliable, remote, and continuous real-time respiratory sound monitor with automated respiratory sound analysis ability is urgently required in many clinical scenarios-such as in monitoring disease progression of coronavirus disease 2019-to replace conventional auscultation with a handheld stethoscope. However, a robust computerized respiratory sound analysis algorithm for breath phase detection and adventitious sound detection at the recording level has not yet been validated in practical applications. In this study, we developed a lung sound database (HF_Lung_V1) comprising 9,765 audio files of lung sounds (duration of 15 s each), 34,095 inhalation labels, 18,349 exhalation labels, 13,883 continuous adventitious sound (CAS) labels (comprising 8,457 wheeze labels, 686 stridor labels, and 4,740 rhonchus labels), and 15,606 discontinuous adventitious sound labels (all crackles). We conducted benchmark tests using long short-term memory (LSTM), gated recurrent unit (GRU), bidirectional LSTM (BiLSTM), bidirectional GRU (BiGRU), convolutional neural network (CNN)-LSTM, CNN-GRU, CNN-BiLSTM, and CNN-BiGRU models for breath phase detection and adventitious sound detection. We also conducted a performance comparison between the LSTM-based and GRU-based models, between unidirectional and bidirectional models, and between models with and without a CNN. The results revealed that these models exhibited adequate performance in lung sound analysis. The GRU-based models outperformed, in terms of F1 scores and areas under the receiver operating characteristic curves, the LSTM-based models in most of the defined tasks. Furthermore, all bidirectional models outperformed their unidirectional counterparts. Finally, the addition of a CNN improved the accuracy of lung sound analysis, especially in the CAS detection tasks.

Metabolic Syndrome Mediates ROS-miR-193b-NFYA-Dependent Downregulation of Soluble Guanylate Cyclase and Contributes to Exercise-Induced Pulmonary Hypertension in Heart Failure With Preserved Ejection Fraction.

BACKGROUND: Many patients with heart failure with preserved ejection fraction have metabolic syndrome and develop exercise-induced pulmonary hypertension (EIPH). Increases in pulmonary vascular resistance in patients with heart failure with preserved ejection fraction portend a poor prognosis; this phenotype is referred to as combined precapillary and postcapillary pulmonary hypertension (CpcPH). Therapeutic trials for EIPH and CpcPH have been disappointing, suggesting the need for strategies that target upstream mechanisms of disease. This work reports novel rat EIPH models and mechanisms of pulmonary vascular dysfunction centered around the transcriptional repression of the soluble guanylate cyclase (sGC) enzyme in pulmonary artery (PA) smooth muscle cells. METHODS: We used obese ZSF-1 leptin-receptor knockout rats (heart failure with preserved ejection fraction model), obese ZSF-1 rats treated with SU5416 to stimulate resting pulmonary hypertension (obese+sugen, CpcPH model), and lean ZSF-1 rats (controls). Right and left ventricular hemodynamics were evaluated using implanted catheters during treadmill exercise. PA function was evaluated with magnetic resonance imaging and myography. Overexpression of nuclear factor Y α subunit (NFYA), a transcriptional enhancer of sGC ß1 subunit (sGCß1), was performed by PA delivery of adeno-associated virus 6. Treatment groups received the SGLT2 inhibitor empagliflozin in drinking water. PA smooth muscle cells from rats and humans were cultured with palmitic acid, glucose, and insulin to induce metabolic stress. RESULTS: Obese rats showed normal resting right ventricular systolic pressures, which significantly increased during exercise, modeling EIPH. Obese+sugen rats showed anatomic PA remodeling and developed elevated right ventricular systolic pressure at rest, which was exacerbated with exercise, modeling CpcPH. Myography and magnetic resonance imaging during dobutamine challenge revealed PA functional impairment of both obese groups. PAs of obese rats produced reactive oxygen species and decreased sGCß1 expression. Mechanistically, cultured PA smooth muscle cells from obese rats and humans with diabetes or treated with palmitic acid, glucose, and insulin showed increased mitochondrial reactive oxygen species, which enhanced miR-193b-dependent RNA degradation of nuclear factor Y α subunit (NFYA), resulting in decreased sGCß1-cGMP signaling. Forced NYFA expression by adeno-associated virus 6 delivery increased sGCß1 levels and improved exercise pulmonary hypertension in obese+sugen rats. Treatment of obese+sugen rats with empagliflozin improved metabolic syndrome, reduced mitochondrial reactive oxygen species and miR-193b levels, restored NFYA/sGC activity, and prevented EIPH. CONCLUSIONS: In heart failure with preserved ejection fraction and CpcPH models, metabolic syndrome contributes to pulmonary vascular dysfunction and EIPH through enhanced reactive oxygen species and miR-193b expression, which downregulates NFYA-dependent sGCß1 expression. Adeno-associated virus-mediated NFYA overexpression and SGLT2 inhibition restore NFYA-sGCß1-cGMP signaling and ameliorate EIPH.

Frataxin deficiency promotes endothelial senescence in pulmonary hypertension.

The dynamic regulation of endothelial pathophenotypes in pulmonary hypertension (PH) remains undefined. Cellular senescence is linked to PH with intracardiac shunts; however, its regulation across PH subtypes is unknown. Since endothelial deficiency of iron-sulfur (Fe-S) clusters is pathogenic in PH, we hypothesized that a Fe-S biogenesis protein, frataxin (FXN), controls endothelial senescence. An endothelial subpopulation in rodent and patient lungs across PH subtypes exhibited reduced FXN and elevated senescence. In vitro, hypoxic and inflammatory FXN deficiency abrogated activity of endothelial Fe-S-containing polymerases, promoting replication stress, DNA damage response, and senescence. This was also observed in stem cell-derived endothelial cells from Friedreich's ataxia (FRDA), a genetic disease of FXN deficiency, ataxia, and cardiomyopathy, often with PH. In vivo, FXN deficiency-dependent senescence drove vessel inflammation, remodeling, and PH, whereas pharmacologic removal of senescent cells in Fxn-deficient rodents ameliorated PH. These data offer a model of endothelial biology in PH, where FXN deficiency generates a senescent endothelial subpopulation, promoting vascular inflammatory and proliferative signals in other cells to drive disease. These findings also establish an endothelial etiology for PH in FRDA and left heart disease and support therapeutic development of senolytic drugs, reversing effects of Fe-S deficiency across PH subtypes.

Current Understanding of Circulating Biomarkers in Pulmonary Hypertension Due to Left Heart Disease.

Pulmonary hypertension due to left heart disease (PH-LHD; Group 2), especially in the setting of heart failure with preserved ejection fraction (HFpEF), is the most frequent cause of PH. Despite its prevalence, no effective therapies for PH-LHD are available at present. This is largely due to the lack of a concise definition for hemodynamic phenotyping, existence of significant gaps in the understanding of the underlying pathology and the impact of associated comorbidities, as well as the absence of specific biomarkers that can aid in the early diagnosis and management of this challenging syndrome. Currently, B-type natriuretic peptide (BNP) and N-terminal proBNP (NT-proBNP) are guideline-recommended biomarkers for the diagnosis and prognosis of heart failure (HF) and PH. Endothelin-1 (ET-1), vascular endothelial growth factor-D (VEGF-D), and microRNA-206 have also been recently identified as new potential circulating biomarkers for patients with PH-LHD. In this review, we aim to present the current state of knowledge of circulating biomarkers that can be used to guide future research toward diagnosis, refine specific patient phenotype, and develop therapeutic approaches for PH-LHD, with a particular focus on PH-HFpEF. Potential circulating biomarkers identified in pre-clinical models of PH-LHD are also summarized here.