Elemental mercury production from contaminated riparian soil suspensions under air and nitrogen bubbling conditions

The dynamic change of redox conditions is a key factor in emission of elemental mercury (Hg0) from riparian soils. The objective of this study was to elucidate the influences of redox conditions on Hg0 emission from riparian soils. Soil suspension experiments were conducted to measure Hg0 emission from five Hg-contaminated soil samples in two redox conditions (i.e., treated with air or with N2). In four of the five samples, Hg0 emission was higher in air treatment than on N2 treatment. Remaining one soil, which has higher organic matter than other soils, showed no distinct difference in Hg0 production between air and N2 treatment. In soil suspensions subject to N2 treatment, the dissolved organic carbon (DOC) and Fe2+ concentrations were 3.38- to 1.34-fold and 1.44- to 2.28-fold higher than those in air treatment, respectively. Positive correlations were also found between the DOC and Fe2+ (r = 0.911, p < 0.01) and Hg2+ (r = 0.815, p < 0.01) concentrations in soil solutions, suggesting Fe2+ formation led to the release of DOC, which bound to Hg2+ in the soil and, in turn, limited the availability of Hg2+ for reduction to Hg0 in N2 treatment. On the other hand, for remaining one soil, more Hg2+ might be adsorbed onto the DOM in the air treatment, resulted in the inhibition of Hg0 production in air treatment. These results imply that the organic matter is important to prevent Hg0 production by changing redox condition. Further study is needed to prove the role of organic matter in the production of Hg0.

Membranous Septum Length Predicts New Conduction Abnormalities in Surgical Aortic Valve Replacement: A Novel Predictor for Permanent Pacemaker Implantation After Surgical Aortic Valve Replacement

INTRODUCTION

The membranous septum (MS) length measured by cardiac computed tomography (CT) is useful for the prediction of permanent pacemaker implantation (PPMI) and new left bundle branch block (LBBB) after transcatheter aortic valve replacement. However, its predictive value for patients undergoing surgical aortic valve replacement (SAVR) is unknown.

METHODS

A total of 2531 consecutive patients were registered in the institutional Society of Thoracic Surgeons database between July 2017 and June 2020. Patients who underwent non-SAVR procedures, had prior pacemaker/implantable cardioverter defibrillator, prior SAVR, no preprocedural CT assessment, or suboptimal CT imaging were excluded.

RESULTS

A total of 126 SAVR with preprocedural CT assessment were analyzed. Bicuspid aortic valve morphology was confirmed on CT in 59.5% of patients. There were three new PPMIs and five new LBBBs observed after SAVR at the time of discharge. In-hospital mortality was 0.8%. Low left ventricular (LV) ejection fraction (<50%), LV mass index >120 g/m2, large right coronary artery height, and MS length <1.5 mm predicted new PPMI/LBBB. Multivariate analysis showed LV mass index >120 g/m2 (odds ratio: 9.165; 95% confidence interval: 1.644-51.080; P = 0.011) and MS length <1.5 mm (odds ratio: 14.449; 95% confidence interval: 1.632-127.954; P = 0.016) were independent predictors for new PPMI/LBBB.

CONCLUSIONS

Short MS length on preoperative cardiac CT is a powerful and novel predictor for the risk of new PPMI/LBBB after SAVR. Special care should be taken in patients with short MS length to avoid suture-mediated trauma.

Mechanisms of action and resistance in histone methylation-targeted therapy

Epigenomes enable the rectification of disordered cancer gene expression, thereby providing new targets for pharmacological interventions. The clinical utility of targeting histone H3 lysine trimethylation (H3K27me3) as an epigenetic hallmark has been demonstrated1-7. However, in actual therapeutic settings, the mechanism by which H3K27me3-targeting therapies exert their effects and the response of tumour cells remain unclear. Here we show the potency and mechanisms of action and resistance of the EZH1-EZH2 dual inhibitor valemetostat in clinical trials of patients with adult T cell leukaemia/lymphoma. Administration of valemetostat reduced tumour size and demonstrated durable clinical response in aggressive lymphomas with multiple genetic mutations. Integrative single-cell analyses showed that valemetostat abolishes the highly condensed chromatin structure formed by the plastic H3K27me3 and neutralizes multiple gene loci, including tumour suppressor genes. Nevertheless, subsequent long-term treatment encounters the emergence of resistant clones with reconstructed aggregate chromatin that closely resemble the pre-dose state. Acquired mutations at the PRC2-compound interface result in the propagation of clones with increased H3K27me3 expression. In patients free of PRC2 mutations, TET2 mutation or elevated DNMT3A expression causes similar chromatin recondensation through de novo DNA methylation in the H3K27me3-associated regions. We identified subpopulations with distinct metabolic and gene translation characteristics implicated in primary susceptibility until the acquisition of the heritable (epi)mutations. Targeting epigenetic drivers and chromatin homeostasis may provide opportunities for further sustained epigenetic cancer therapies.

Biomechanical framework for the inverse dynamic analysis of swimming using hydrodynamic forces from swumsuit

This study aims to integrate an open-source software capable of estimating hydrodynamic forces solely from kinematic data with a full-body biomechanical model of the human body to enable inverse dynamic analyses of swimmers. To demonstrate the methodology, intersegmental forces and joint torques of the lower limbs were computed for a six-beat front crawl swimming motion, acquired at LABIOMEP-UP. The hydrodynamic forces obtained compare well with existing numerical literature. The intersegmental forces and joint torques obtained increase from distal to proximal joints. Overall, the results are consistent with the limited literature on swimming biomechanics, which provides confidence in the presented methodology.

Real-world evidence of trifluridine/tipiracil plus bevacizumab in metastatic colorectal cancer using an administrative claims database in Japan

BACKGROUND

Trifluridine/tipiracil (FTD/TPI) and regorafenib (REG) are standard therapies for refractory metastatic colorectal cancer (mCRC). No results of large real-world data directly comparing FTD/TPI + bevacizumab (BEV) with FTD/TPI or REG monotherapy have been reported. We evaluated the efficacy and safety of FTD/TPI + BEV in a real-world setting.

MATERIALS AND METHODS

This retrospective study used a Japanese claims database provided by Medical Data Vision Co., Ltd. (Tokyo, Japan). Eligible patients were aged 20 years and over with a diagnosis of mCRC, and received their first dose of FTD/TPI or REG from 2014 to 2021. The primary endpoint was overall survival (OS) in a propensity score matching (PSM) population in which PSM was carried out by matching using a 1 : 1 ratio for the FTD/TPI + BEV group and the control group (FTD/TPI or REG) by propensity score. To enhance robustness, sensitivity analyses of OS were carried out using the inverse probability treatment weighted (IPTW) approach and the analysis in the all eligible population. Secondary endpoints included time to treatment discontinuation (TTD), incidence of adverse events, and post-treatment.

RESULTS

Eligible population was 2369 for the FTD/TPI + BEV group and 9318 for the control group. The PSM population was 1787 for each group. Median OS (mOS) was longer in the FTD/TPI + BEV group compared to the control group [17.0 versus 11.6 months, hazard ratio (HR) = 0.70, P < 0.001] in the PSM population. Similarly, mOS was longer for the FTD/TPI + BEV group compared to that for the control group in IPTW analyses and in the all eligible population (both HRs = 0.68). Median TTD was 3.3 months for the FTD/TPI + BEV group and 1.8 months for the control group in the PSM population (P < 0.001).

CONCLUSIONS

Real-world data showed that FTD/TPI + BEV was significantly associated with OS and TTD compared to FTD/TPI or REG. In clinical practice, FTD/TPI + BEV can be a favorable regimen for refractory mCRC.

CD30 induces Reed-Sternberg cell-like morphology and chromosomal instability in classic Hodgkin lymphoma cell lines

Classic Hodgkin lymphoma (cHL) is characterized by multinucleated cells called Reed-Sternberg (RS) cells and genetic complexity. Although CD30 also characterizes cHL cells, its biological roles are not fully understood. In this report, we examined the link between CD30 and these characteristics of cHL cells. CD30 stimulation increased multinucleated cells resembling RS cells. We found chromatin bridges, a cause of mitotic errors, among the nuclei of multinucleated cells. CD30 stimulation induced DNA double-strand breaks (DSBs) and chromosomal imbalances. RNA sequencing showed significant changes in the gene expression by CD30 stimulation. We found that CD30 stimulation increased intracellular reactive oxygen species (ROS), which induced DSBs and multinucleated cells with chromatin bridges. The PI3K pathway was responsible for CD30-mediated generation of multinucleated cells by ROS. These results suggest that CD30 involves generation of RS cell-like multinucleated cells and chromosomal instability through induction of DSBs by ROS, which subsequently induces chromatin bridges and mitotic error. The results link CD30 not only to the morphological features of cHL cells, but also to the genetic complexity, both of which are characteristic of cHL cells.

CD30 Expression and Its Functions during the Disease Progression of Adult T-Cell Leukemia/Lymphoma

CD30, a member of the tumor necrosis factor receptor superfamily, plays roles in pro-survival signal induction and cell proliferation in peripheral T-cell lymphoma (PTCL) and adult T-cell leukemia/lymphoma (ATL). Previous studies have identified the functional roles of CD30 in CD30-expressing malignant lymphomas, not only PTCL and ATL, but also Hodgkin lymphoma (HL), anaplastic large cell lymphoma (ALCL), and a portion of diffuse large B-cell lymphoma (DLBCL). CD30 expression is often observed in virus-infected cells such as human T-cell leukemia virus type 1 (HTLV-1). HTLV-1 is capable of immortalizing lymphocytes and producing malignancy. Some ATL cases caused by HTLV-1 infection overexpress CD30. However, the molecular mechanism-based relationship between CD30 expression and HTLV-1 infection or ATL progression is unclear. Recent findings have revealed super-enhancer-mediated overexpression at the CD30 locus, CD30 signaling via trogocytosis, and CD30 signaling-induced lymphomagenesis in vivo. Successful anti-CD30 antibody-drug conjugate (ADC) therapy for HL, ALCL, and PTCL supports the biological significance of CD30 in these lymphomas. In this review, we discuss the roles of CD30 overexpression and its functions during ATL progression.

The oncogenic driving force of CD30 signaling-induced chromosomal instability in adult T-cell leukemia/lymphoma

Adult T-cell leukemia/lymphoma (ATL) develops via stepwise accumulation of gene mutations and chromosome aberrations. However, the molecular mechanisms underlying this tumorigenic process are poorly understood. We previously reported the presence of a biological link between the expression of CD30, which serves as a marker for ATL progression, and the actively proliferating fraction of human T-cell leukemia virus type 1 (HTLV-1)-infected cells that display polylobulation. Here, we demonstrated that CD30 signaling induced chromosomal instability with clonal expansion through DNA double-strand breaks (DSBs) via an increase of intracellular reactive oxygen species. CD30⁺ ATL cells were composed of subclones with additional genomic aberrations compared with CD30^- ATL cells in ATL patients. Furthermore, we found an accumulation of copy number loss of DSB repair-related genes as the disease progressed. Taken together, CD30 expression on ATL cells appears to be correlated with genomic instability, suggesting that CD30 signaling is one of the oncogenic factors of ATL progression with clonal evolution. This study provides new insight into the biological roles of CD30 signaling and could improve our understanding of tumorigenic processes of HTLV-1-infected cells.

RAISING is a high-performance method for identifying random transgene integration sites

Both natural viral infections and therapeutic interventions using viral vectors pose significant risks of malignant transformation. Monitoring for clonal expansion of infected cells is important for detecting cancer. Here we developed a novel method of tracking clonality via the detection of transgene integration sites. RAISING (Rapid Amplification of Integration Sites without Interference by Genomic DNA contamination) is a sensitive, inexpensive alternative to established methods. Its compatibility with Sanger sequencing combined with our CLOVA (Clonality Value) software is critical for those without access to expensive high throughput sequencing. We analyzed samples from 688 individuals infected with the retrovirus HTLV-1, which causes adult T-cell leukemia/lymphoma (ATL) to model our method. We defined a clonality value identifying ATL patients with 100% sensitivity and 94.8% specificity, and our longitudinal analysis also demonstrates the usefulness of ATL risk assessment. Future studies will confirm the broad applicability of our technology, especially in the emerging gene therapy sector.

Significance of soil moisture on temperature dependence of Hg emission

Soil moisture is a key factor for mercury (Hg) emission from soil. Despite its significance for Hg emissions, the effect of soil moisture on Hg flux and fractions has not been thoroughly investigated. The objective of this study was to elucidate the influences of soil moisture and temperature on Hg fluxes from soils and Hg fractions. A kinetic study was performed to measure Hg emission fluxes of six soil samples under different temperature (T) (15 °C, 20 °C, 25 °C, 30 °C, and 35 °C) and moisture conditions (0%, 10%, and 20% added water). The results showed that the Hg fluxes increased with increases in T and soil moisture. A linear correlation was found between ln (Hg emission flux) and 1/T for the six soil samples at different moisture contents (R² = 0.73-0.99). The range of activation energy (Ea) values was 25.31-57.86 kJ/mol. The Hg fractions in soils of different moisture content were determined by a sequential extraction method. The results demonstrated that soil moisture affected the Hg fractions in soils. The Ea values had different relationships with soil moisture in different soils. There were correlations between Ea and the elemental and mercuric sulfide fractions for air-dried soils. However, for moist soils, Ea was negatively correlated with the water-soluble and acid-soluble fractions. Collectively, the combination of the Hg emission kinetics and Hg fraction measurement of different moist soils indicated that Hg emission was affected by both total Hg concentration and Hg fractions.

Multiphase Assessment of Mitral Annular Dynamics in Consecutive Patients With Significant Mitral Valve Disease

OBJECTIVES

The aim of this study was to clarify the dynamics of the mitral annulus throughout the cardiac cycle and its relevance to transcatheter mitral valve replacement (TMVR) sizing and case selection.

BACKGROUND

Limited data are available regarding the relevance of mitral annular (MA) and neo-left ventricular outflow tract (LVOT) dynamics in the overall population presenting with significant mitral valve disease.

METHODS

Patients attending a combined surgical-transcatheter heart valve clinic for severe symptomatic mitral valve disease were assessed using multiphase computed tomography. The relative influence of MA and neo-LVOT dynamics to TMVR case selection was studied.

RESULTS

A total of 476 patients with significant mitral valve disease were evaluated. In 99 consecutive patients with severe mitral regurgitation, a 10-phase assessment showed that the mitral annulus was on average largest in late systole. On comparing maximal MA dimension with late systolic dimension, TMVR size assignment changed in 24.2% of patients. If the average MA perimeter was used to determine sizing, 48.5% were excluded because of MA dimension being too large; in a multiphase assessment of the neo-LVOT, an additional 16.2% were excluded on the basis of neo-LVOT dimension. In an expanded series of 312 consecutive patients, selection protocol influenced anatomical exclusion: a manufacturer-proposed early systolic approach excluded 69.2% of patients, whereas a late systolic approach excluded 82.7% of patients, the vast majority because of large mitral annuli.

CONCLUSIONS

Contemporary TMVR can treat only a minority of patients with severe mitral regurgitation, principally because of limitations of large MA dimension.

Conduction Disturbances and Pacing in Transcatheter Aortic Valve Replacement

Conduction disturbances (CDs) after transcatheter artic replacement remain a clinical concern and relatively common complication. A recent meta-analysis showed both new-onset persistent left bundle branch block and new permanent pacemaker implantation were related to all-cause death with risk ratio 1.32 (95% confidence interval [CI] 1.17 to 1.49; P<.001) and 1.17 (95% CI 1.11-1.25; P<.001) at 1 year, respectively. Preprocedural computed tomography imaging can highlight potential risk factors for CDs, such as membranous septum length, device landing zone calcium, and the annulus size/degree of device oversizing.

Balloon post-dilatation improves long-term valve performance after balloon-expandable valve implantation

BACKGROUND

The impact of balloon post-dilatation (BPD) on short- and long-term valve performance after Sapien 3 (S3) implantation is unknown. This study aimed to evaluate the impact of balloon post-dilatation (BPD) on short- and long-term valve performance after the implantation of S3.

METHODS

A total of 846 patients implanted with S3 from the OCEAN-TAVI registry were included in this study. The patients were divided into BPD and non-BPD groups. The clinical outcomes and valve functions were compared.

RESULTS

The BPD group included 173 (20.4%) patients and the non-BPD group comprised 673 (79.6%) patients. The prosthesis-patient mismatch (PPM) rates were significantly lower in the BPD group than in the non-BPD group before and after propensity score matching at in-hospital follow-up (before matching: 12 [7.1%] vs. 108 [16.3%], p = 0.002; after matching: 8 [6.3%] vs. 19 [14.8%], p = 0.027) and at 1-year follow-up (before matching: 14 [12.5%] vs. 112 [23.6%], p = 0.010; after matching: 9 [10.5%] vs. 19 [22.1%], p = 0.039). The rates of acute kidney injury, cardiac tamponade, and in-hospital cardiovascular death were significantly higher in the BPD group than in the non-BPD group (acute kidney injury: 22 [12.7%] vs. 33 [4.9%], p < 0.001; cardiac tamponade: 3 [1.7%] vs. 2 [0.3%], p = 0.028; in-hospital cardiovascular death: 4 [2.3%] vs. 3 [0.4%], p = 0.016). After matching, these clinical outcomes were similar between the BPD and non-BPD groups.

CONCLUSIONS

The BPD group demonstrated better short- and long-term valve performance. Caution is needed to avoid procedure-related complications in patients undergoing BPD.

Relationship between vancomycin-associated nephrotoxicity and the number of combined nephrotoxic agents

Vancomycin is associated with nephrotoxicity; however, the influence of the number of combined nephrotoxic agents on the incidence of vancomycin nephrotoxicity has not been clarified. We investigated patient backgrounds in 148 inpatients who received vancomycin treatment. The patients were divided into nephrotoxicity (n=35) and non-nephrotoxicity (n=113) groups. A comparison of the patient backgrounds in the two groups revealed significant differences in weight, changes in serum creatinine before vancomycin administration, blood urea nitrogen to serum creatinine ratio, length of vancomycin therapy, vancomycin trough concentration, and number of combined nephrotoxic agents. Multiple logistic regression analysis using these six factors as autonomous variables showed that the highest vancomycin trough concentration (odds ratio, 1.080; 95% confidence interval, 1.030-1.140; p = 0.003) and the number of combined nephrotoxic agents (odds ratio, 1.590; 95% confidence interval, 1.120-2.260; p = 0.010) were significantly related to nephrotoxicity.

Differentiation of Hodgkin lymphoma cells by reactive oxygen species and regulation by heme oxygenase-1 through HIF-1α

We previously indicated that Hodgkin lymphoma (HL) cells contain a small side population (SP) that differentiate into a large major population (MP) with giant Hodgkin and Reed‐Sternberg (H and RS)‐like cells. However, its molecular mechanisms are not fully understood. In this study, we found that intracellular reactive oxygen species (ROS) are low in the SP compared to the MP. Hydrogen peroxide induces large H‐ and RS‐like cells in HL cell lines, but induces cell death in unrelated lymphoid cell lines. Microarray analyses revealed the enrichment of upregulated genes under hypoxic conditions in the SP compared to the MP, and we verified that the SP cells are hypoxic. Hypoxia inducible factor (HIF)‐1α was preferentially expressed in the SP. CoCl₂, a HIF‐1α stabilizer, blunted the effect of hydrogen peroxide. Heme oxygenase‐1 (HO‐1), a scavenger of ROS, was triggered by HIF‐1α. The effect of hydrogen peroxide was inhibited by HO‐1 induction, whereas it was promoted by HO‐1 knockdown. HO‐1 inhibition by zinc protoporphyrin promoted the differentiation and increased ROS. These results stress the unique roles of ROS in the differentiation of HL cells. Immature HL cells are inhibited from differentiation by a reduction of ROS through the induction of HO‐1 via HIF‐1α. The breakdown of this might cause the accumulation of intracellular ROS, resulting in the promotion of HL cell differentiation.

Investigation of immune complexes formed by mitochondrial antigens containing a new lipoylated site in sera of primary biliary cholangitis patients

Primary biliary cholangitis (PBC) is characterized by the presence of serum anti-mitochondrial autoantibodies (AMAs). To date, four antigens among the 2-oxo-acid dehydrogenase complex family, which commonly have lipoyl domains as an epitope, have been identified as AMA-corresponding antigens (AMA-antigens). It has recently been reported that AMAs react more strongly with certain chemically modified mimics than with the native lipoyl domains in AMA-antigens. Moreover, high concentrations of circulating immune complexes (ICs) in PBC patients have been reported. However, the existence of ICs formed by AMAs and their antigens has not been reported to date. We hypothesized that AMAs and their antigens formed ICs in PBC sera, and analyzed sera of PBC and four autoimmune diseases (Sjögren's syndrome, systemic lupus erythematosus, systemic scleroderma, and rheumatoid arthritis) using immune complexome analysis, in which ICs are separated from serum and are identified by nano-liquid chromatography-tandem mass spectrometry. To correctly assign MS/MS spectra to peptide sequences, we used a protein-search algorithm that including lipoylation and certain xenobiotic modifications. We found three AMA-antigens, the E2 subunit of the pyruvate dehydrogenase complex (PDC-E2), the E2 subunit of the 2-oxo-glutarate dehydrogenase complex (OGDC-E2) and dihydrolipoamide dehydrogenase binding protein (E3BP), by detecting peptides containing lipoylation and xenobiotic modifications from PBC sera. Although the lipoylated sites of these peptides were different from the well-known sites, abnormal lipoylation and xenobiotic modification may lead to production of AMAs and the formation ICs. Further investigation of the lipoylated sites, xenobiotic modifications, and IC formation will lead to deepen our understanding of PBC pathogenesis.

Immune complexome analysis reveals the presence of immune complexes and identifies disease-specific immune complex antigens in saliva samples from patients with Sjögren's syndrome

Sjögren's syndrome (SS) is a chronic autoimmune disease that mainly damages the salivary and lacrimal glands. Immune complex (IC) formation triggers local inflammation through IC deposition and decreased antigen function. Some ICs can leak from the lesion and into the saliva, but no salivary ICs have been reported to date. We used immune complexome analysis to comprehensively identify antigens incorporated into IC (IC-antigens) in saliva samples from patients with SS (n = 9) or with xerostomia (n = 7). Neutrophil defensin 1 (67%), small proline-rich protein 2D (67%), myeloperoxidase (44%), neutrophil elastase (44%), cathepsin G (33%), nuclear mitotic apparatus 1 (33%) and phosphatidylinositol 4-phosphate 3-kinase C2 domain-containing subunit gamma (33%) were identified as new IC-antigens specifically and frequently detected in the saliva of SS patients. Of these, neutrophil defensin 1, myeloperoxidase, neutrophil elastase and cathepsin G are neutrophil intracellular proteins, which suggests that repeated destruction of neutrophils due to abnormal autoimmunity may be involved in the pathogenesis of SS. We also analyzed serum samples from three SS patients. There was little overlap of IC-antigens between two of the samples (fewer than 30% of the IC-antigens in the saliva samples), suggesting that many ICs are formed locally and independently of the circulation. In addition, we found that four SS-specific salivary antigens show sequence homology with several proteins of oral microbiomes but no antigen has homology with Epstein-Barr virus proteins. The homology between some IC-antigens and oral microbiome proteins may indicate the impact of oral infection on local autoimmunity through molecular mimicry theory.

Sex differences in clinical outcomes after rotational atherectomy of calcified coronary stenoses: from multicenter registry

BACKGROUND

Recent improvements in devices and medications may diminish the risk of adverse events following percutaneous coronary intervention (PCI) in women. However, complex calcified coronary lesions are increasingly being encountered in clinical practice, which remain challenging for contemporary PCI. Rotational atherectomy (RA) of severely calcified lesions is an option that facilitates the technical success of PCI. We aimed to examine sex differences in long-term clinical prognoses after PCI with RA in the drug-eluting stent (DES) era.

METHODS AND RESULTS

We evaluated J2T ROTA registry data from 1,090 patients with severely calcified de novo coronary artery stenoses who underwent PCI using RA at 3 hospitals between 2004 and 2015. After excluding patients who received regular hemodialysis, 788 patients, including 570 men and 218 women, were ultimately analyzed. The primary endpoint was major adverse cardiovascular and cerebrovascular events (MACCE), which included death, acute coronary syndrome (ACS), and stroke. The women were significantly older, and presented more frequently with chronic kidney disease, ACS, atrial fibrillation, lower body mass indexes, and worse lipid profiles than the men. During the observation period, MACCE occurred in 197 patients (25%) (118 deaths, 29 strokes, and 50 ACS). In the unmatched population, women had a higher MACCE rate than men (hazard ratio: 1.48, [95% confidence interval: 1.07-2.06]). However, sex was not associated with MACCE in the propensity score-matched population.

CONCLUSION

In the DES era, differences between sexes were not observed in relation to long-term MACCE in patients undergoing PCI with RA for severely calcified coronary artery stenoses.