Mitral regurgitation is associated with similar loss of von Willebrand factor large multimers but lower frequency of anemia compared with aortic stenosis.

Background: Various cardiovascular diseases cause acquired von Willebrand syndrome (AVWS), which is characterized by a decrease in high-molecular-weight (large) von Willebrand factor (VWF) multimers. Mitral regurgitation (MR) has been reported as a cause of AVWS. However, much remains unclear about AVWS associated with MR. Objectives: To evaluate VWF multimers in MR patients and examine their impact on clinical characteristics. Methods: Moderate or severe MR patients (n = 84) were enrolled. VWF parameters such as the VWF large multimer index (VWF-LMI), a quantitative value that represents the amount of VWF large multimers, and clinical data were prospectively analyzed. Results: At baseline, the mean hemoglobin level was 12.9 ± 1.9 g/dL and 58 patients (69.0%) showed loss of VWF large multimers defined as VWF-LMI < 80%. VWF-LMI in patients with degenerative MR was lower than in those with functional MR. VWF-LMI appeared to be restored the day after mitral valve intervention, and the improvement was maintained 1 month after the intervention. Seven patients (8.3%) had a history of bleeding, 6 (7.1%) of whom had gastrointestinal bleeding. Gastrointestinal endoscopy was performed in 23 patients (27.4%) to investigate overt gastrointestinal bleeding, anemia, etc. Angiodysplasia was detected in 2 of the 23 patients (8.7%). Conclusion: Moderate or severe MR is frequently associated with loss of VWF large multimers, and degenerative MR may cause more severe loss compared with functional MR. Mitral valve intervention corrects the loss of VWF large multimers. Gastrointestinal bleeding may be relatively less frequent and hemoglobin level remains stable in MR patients.

Proximal ligation technique prevents thrombus formation in the pulmonary vein stump after lobectomy.

PURPOSE: To assess the risk factors for thrombosis in the pulmonary vein stump (PVT) and the efficacy of proximal ligation in preventing PVT after lobectomy. METHODS: In total, 649 surgical patients with lung cancer were retrospectively reviewed. To compare the clinical effectiveness of PV proximal ligation, the simple stapler group (290 patients) and the proximal ligation group (359 patients who underwent thread ligation at the pericardial reflection with/without a stapler) were analyzed. RESULTS: In the simple stapler group, 12 of 290 patients (4.1%) developed PVT. Among these, 9 of 58 underwent left upper lobectomy (LUL). In contrast, 5 of the 359 patients (1.4%) in the proximal ligation group developed PVT. All five patients received LUL. The incidence of PVT in the proximal ligation group was significantly lower than that in the simple stapler group (p = 0.0295) as well as in the analysis by LUL alone (p = 0.0263). A logistic regression analysis indicated that higher BMI and LUL were associated with the development of PVT (p = 0.0031, p < 0.0001), and PV proximal ligation reduced PVT (p = 0.0055). CONCLUSION: Proximal ligation of the PV has the potential to prevent PVT, especially after LUL.

Concomitant Mitral Regurgitation in Severe Aortic Stenosis　- Insights From the CURRENT AS Registry-2.

BACKGROUND: Data on concomitant mitral regurgitation (MR) in patients with severe aortic stenosis (AS) are scarce.Methods and Results: We investigated the risk of concomitant MR in patients with severe AS in the CURRENT AS Registry-2 according to initial treatment strategy (transcatheter aortic valve implantation [TAVI], surgical aortic valve replacement [SAVR], or conservative). Among 3,365 patients with severe AS, 384 (11.4%) had moderate/severe MR (TAVI: n=126/1,148; SAVR: n=68/591; conservative: n=190/1,626). The cumulative 3-year incidence for death or heart failure (HF) hospitalization was significantly higher in the moderate/severe than no/mild MR group in the entire population (54.6% vs. 34.3%, respectively; P<0.001) and for each treatment strategy (TAVI: 45.0% vs. 31.8% [P=0.006]; SAVR: 31.9% vs. 18.7% [P<0.001]; conservative: 67.8% vs. 41.6% [P<0.001]). The higher adjusted risk of moderate/severe MR relative to no/mild MR for death or HF hospitalization was not significant in the entire population (hazard ratio [HR] 1.15; 95% confidence interval [CI] 0.95-1.39; P=0.15); however, the risk was significant in the SAVR (HR 1.92; 95% CI 1.04-3.56; P=0.04) and conservative (HR 1.30; 95% CI 1.02-1.67; P=0.04) groups, but not in the TAVI group (HR 1.03; 95% CI 0.70-1.52; P=0.86), despite no significant interaction (Pinteraction=0.37). CONCLUSIONS: Moderate/severe MR was associated with a higher risk for death or HF hospitalization in the initial SAVR and conservative strategies, while the association was less pronounced in the initial TAVI strategy.

Prostanoids Regulate Angiogenesis and Lymphangiogenesis in Pathological Conditions.

Angiogenesis, the formation of new blood vessels from the preexistent microvasculature, is an essential component of wound repair and tumor growth. Nonsteroidal anti-inflammatory drugs that suppress prostanoid biosynthesis are known to suppress the incidence and progression of malignancies including colorectal cancers, and also to delay the wound healing. However, the precise mechanisms are not fully elucidated. Accumulated results obtained from prostanoid receptor knockout mice indicate that a prostaglandin E-type receptor signaling EP3 in the host microenvironment is critical in tumor angiogenesis inducing vascular endothelial growth factor A (VEGF-A). Further, lymphangiogenesis was also enhanced by EP signaling via VEGF-C/D inductions in pathological settings. These indicate the importance of EP receptor to facilitate angiogenesis and lymphangiogenesis in vivo. Prostanoids act beyond their commonly understood activities in smooth muscle contraction and vasoactivity, both of which are quick responses elicited within several seconds on stimulations. Prostanoid receptor signaling will be a potential therapeutic target for disease conditions related to angiogenesis and lymphangiogenesis.

Evaluation of antimicrobial susceptibility tests for Acinetobacter and Pseudomonas species using disks containing a high dose of meropenem.

The emergence and dissemination of carbapenem-resistant species of Acinetobacter and Pseudomonas have become a serious health concern. Routine antimicrobial disk susceptibility tests in clinical laboratories cannot distinguish between isolates that are highly carbapenem-resistant and those that are moderately carbapenem-resistant. The present study describes antimicrobial susceptibility tests using disks containing high doses (1000 µg) of meropenem. The diameters of inhibition zones were significantly negatively correlated with the MICs of Pseudomonas and Acinetobacter species for meropenem (R2: 0.93 and 0.91, respectively) and imipenem (R2: 0.75 and 0.84, respectively). Double disk synergy tests using clavulanic acid or sodium mercaptoacetate can detect ESBL or MBL producers. Susceptibility tests using disks containing high doses of meropenem can easily detect highly carbapenem-resistant isolates in a quantitative manner. These disks may be useful in bacteriological laboratories because of their technical ease, stability, and relatively low cost.

von Willebrand factor Ristocetin co-factor activity to von Willebrand factor antigen level ratio for diagnosis of acquired von Willebrand syndrome caused by aortic stenosis.

Background: Severe aortic stenosis (AS) causes acquired von Willebrand syndrome by the excessive shear stress-dependent cleavage of high molecular weight multimers of von Willebrand factor (VWF). While the current standard diagnostic method is so-called VWF multimer analysis that is western blotting under nonreducing conditions, it remains unclear whether a ratio of VWF Ristocetin co-factor activity (VWF:RCo) to VWF antigen levels (VWF:Ag) of <0.7, which can be measured with an automated coagulation analyzer in clinical laboratories and is used for the diagnosis of hereditary von Willebrand disease. Objectives: To evaluated whether the VWF:RCo/VWF:Ag is useful for the diagnosis of AS-induced acquired von Willebrand syndrome. Methods: VWF:RCo and VWF:Ag were evaluated with the VWF large multimer index as a reference, which represents the percentage of a patient's VWF high molecular weight multimer ratio to that of standard plasma in the VWF multimer analysis. Results: We analyzed 382 patients with AS having transaortic valve maximal pressure gradients of >30 mmHg, 27 patients with peripheral artery disease, and 46 control patients free of cardiovascular disease with osteoarthritis, diabetes, and so on. We assumed a large multimer index of <80% as loss of VWF large multimers since 59.0% of patients with severe AS had the indices of <80%, while no control patients or patients with peripheral artery disease, except for 2 patients, exhibited the indices of <80%. The VWF:RCo/VWF:Ag ratios, measured using an automated blood coagulation analyzer, were correlated with the indices (rs = 0.470, P < .001). When the ratio of <0.7 was used as a cut-off point, the sensitivity and specificity to VWF large multimer indices of <80% were 0.437 and 0.826, respectively. Conclusion: VWF:RCo/VWF:Ag ratios of <0.7 may indicate loss of VWF large multimers with high specificity, but low sensitivity. VWF:RCo/VWF:Ag ratios in patients with AS having a ratio of <0.7 may be useful for monitoring the loss of VWF large multimers during their clinical courses.

KUS121, a VCP modulator, has an ameliorating effect on acute and chronic heart failure without calcium loading via maintenance of intracellular ATP levels.

AIMS: As heart failure (HF) progresses, ATP levels in myocardial cells decrease, and myocardial contractility also decreases. Inotropic drugs improve myocardial contractility but increase ATP consumption, leading to poor prognosis. Kyoto University Substance 121 (KUS121) is known to selectively inhibit the ATPase activity of valosin-containing protein, maintain cellular ATP levels, and manifest cytoprotective effects in several pathological conditions. The aim of this study is to determine the therapeutic effect of KUS121 on HF models. METHODS AND RESULTS: Cultured cell, mouse, and canine models of HF were used to examine the therapeutic effects of KUS121. The mechanism of action of KUS121 was also examined. Administration of KUS121 to a transverse aortic constriction (TAC)-induced mouse model of HF rapidly improved the left ventricular ejection fraction and improved the creatine phosphate/ATP ratio. In a canine model of high frequency-paced HF, administration of KUS121 also improved left ventricular contractility and decreased left ventricular end-diastolic pressure without increasing the heart rate. Long-term administration of KUS121 to a TAC-induced mouse model of HF suppressed cardiac hypertrophy and fibrosis. In H9C2 cells, KUS121 reduced ER stress. Finally, in experiments using primary cultured cardiomyocytes, KUS121 improved contractility and diastolic capacity without changing peak Ca2+ levels or contraction time. These effects were not accompanied by an increase in cyclic adenosine monophosphate or phosphorylation of phospholamban and ryanodine receptors. CONCLUSIONS: KUS121 ameliorated HF by a mechanism totally different from that of conventional catecholamines. We propose that KUS121 is a promising new option for the treatment of HF.

The inter-laboratory validation study of EpiSensA for predicting skin sensitization potential.

The Epidermal Sensitization Assay (EpiSensA) is a reconstructed human epidermis (RhE)-based gene expression assay for predicting the skin sensitization potential of chemicals. Since the RhE model is covered by a stratified stratum corneum, various kinds of test chemicals, including lipophilic ones and pre-/pro-haptens, can be tested with a route of exposure akin to an in vivo assay and human exposure. This article presents the results of a formally managed validation study of the EpiSensA that was carried out by three participating laboratories. The purpose of this validation study was to assess transferability of the EpiSensA to new laboratories along with its within- (WLR) and between-laboratory reproducibility (BLR). The validation study was organized into two independent stages. As demonstrated during the first stage, where three sensitizers and one non-sensitizer were correctly predicted by all participating laboratories, the EpiSensA was successfully transferred to all three participating laboratories. For Phase I of the second stage, each participating laboratory performed three experiments with an identical set of 15 coded test chemicals resulting in WLR of 93.3%, 93.3%, and 86.7%, respectively. Furthermore, when the results from the 15 test chemicals were combined with those of the additional 12 chemicals tested in Phase II of the second stage, the BLR for 27 test chemicals was 88.9%. Moreover, the predictive capacity among the three laboratories showed 92.6% sensitivity, 63.0% specificity, 82.7% accuracy, and 77.8% balanced accuracy based on murine local lymph node assay (LLNA) results. Overall, this validation study concluded that EpiSensA is easily transferable and sufficiently robust for assessing the skin sensitization potential of chemicals.

In-hospital outcomes after SAVR or TAVI in patients with severe aortic stenosis.

There were no data comparing the in-hospital outcomes after transcatheter aortic valve implantation (TAVI) with those after surgical aortic valve replacement (SAVR) in Japan. Among consecutive patients with severe AS between April 2018 and December 2020 in the CURRENT AS Registry-2, we identified 1714 patients who underwent aortic valve replacement (TAVI group: 1134 patients, and SAVR group: 580 patients). Patients in the TAVI group were much older (84.4 versus 73.6 years, P < 0.001) and more often had comorbidities than those in the SAVR group. In-hospital death rate was numerically lower in the TAVI group than in the SAVR group (0.6% versus 2.2%). After excluding patients with dialysis, in-hospital death rate was very low and comparable in the TAVI and SAVR groups (0.6% versus 0.8%). The rates of major bleeding and new-onset atrial fibrillation during index hospitalization were higher after SAVR than after TAVI (72% versus 20%, and 26% versus 4.6%, respectively), while the rate of pacemaker implantation was higher after TAVI than after SAVR (8.1% versus 2.4%). Regarding the echocardiographic data at discharge, the prevalence of patient-prosthesis mismatch was lower in the TAVI group than in the SAVR group (moderate: 9.0% versus 26%, and severe: 2.6% versus 4.8%). In this real-world data in Japan, TAVI compared with SAVR was chosen in much older patients with more comorbidities with severe AS. In-hospital death rate was numerically lower in the TAVI group than in the SAVR group.

A case of a systemic cancer-associated thrombosis successfully treated with multi-disciplinary treatment including anticoagulation therapy and anticancer drug therapy.

Background: Cancer-associated thrombosis (CAT) is one of the major complications during the treatment course of cancer, which often challenges clinicians in daily clinical practice despite anticoagulation therapy. Case summary: A 57-year-old man with a history of a liver transplantation was diagnosed with post-transplant lymphoproliferative disorders. He developed severe systemic thromboses including a massive pulmonary embolism and was treated with anticoagulation therapy including a factor Xa inhibitor. However, the systemic thromboses worsened despite the anticoagulation therapy. During the acute treatment course of the thromboses, we administered anticancer drug therapy in hopes of an improvement in the activity of the cancer status leading to a favourable effect on the thrombosis status. Multi-disciplinary treatment including anticoagulation therapy and anticancer drug therapy successfully improved the systemic thrombosis. Discussion: Anticoagulation therapy is a standard treatment for CAT; however, some cases of CAT do not successfully improve despite anticoagulation therapy, partly due to a highly active cancer status. Anticancer drug therapy might increase the risk of a thrombosis, whereas it could improve the activity of the cancer status leading to a decreased risk of a thrombosis. A multi-disciplinary therapy might be a reasonable option especially for CAT with a highly active cancer status.

Klebsiella pneumoniae co-harbouring bla NDM-1 , armA and mcr-10 isolated from blood samples in Myanmar.

Background. The spread of Enterobacteriaceae coproducing carbapenemases, 16S rRNA methylase and mobile colistin resistance proteins (MCRs) has become a serious public health problem worldwide. This study describes two clinical isolates of Klebsiella pneumoniae coharbouring bla IMP-1, armA and mcr-10.Methods. Two clinical isolates of K. pneumoniae resistant to carbapenems and aminoglycosides were obtained from two patients at a hospital in Myanmar. Their minimum inhibitory concentrations (MICs) were determined by broth microdilution methods. The whole-genome sequences were determined by MiSeq and MinION methods. Drug-resistant factors and their genomic environments were determined.Results. The two K. pneumoniae isolates showed MICs of ≥4 and ≥1024 µg ml-1 for carbapenems and aminoglycosides, respectively. Two K. pneumonaie harbouring mcr-10 were susceptible to colistin, with MICs of ≤0.015 µg ml-1 using cation-adjusted Mueller-Hinton broth, but those for colistin were significantly higher (0.5 and 4 µg ml-1) using brain heart infusion medium. Whole-genome analysis revealed that these isolates coharboured bla NDM-1, armA and mcr-10. These two isolates showed low MICs of 0.25 µg ml-1 for colistin. Genome analysis revealed that both bla NDM-1 and armA were located on IncFIIs plasmids of similar size (81 kb). The mcr-10 was located on IncM2 plasmids of sizes 220 or 313 kb in each isolate. These two isolates did not possess a qseBC gene encoding a two-component system, which is thought to regulate the expression of mcr genes.Conclusion. This is the first report of isolates of K. pneumoniae coharbouring bla NDM-1, armA and mcr-10 obtained in Myanmar.

New Neuromuscular Training for Peripheral Nerve Disorders Using an Ankle Joint Hybrid Assistive Limb: A Case Series.

Peripheral nerve disorder of the lower extremities causes drop foot and disturbs the daily living activities of patients. The ankle joint hybrid assistive limb (HAL) provides voluntary ankle joint training using surface bioelectrical signals from the muscles of the lower extremities. We investigated the neurological effects of ankle joint HAL training in three patients. Sensory nerve action potentials (SNAPs) and compound muscle action potentials (CMAPs) were analyzed for the peroneal and tibial nerves prior to the first ankle joint HAL training session. Integrated surface electromyography EMG signals were recorded before and after the HAL training sessions to evaluate the effects of training for neuromuscular disorders. The patients were hospitalized to receive rehabilitation with HAL training for 2 weeks. The HAL training was performed daily with two 60 min sessions. All cases demonstrated severe neuromuscular impairment according to the result of the CMAP. All integrated EMG measurements of antagonistic muscle activities decreased after the ankle joint HAL training. The manual muscle testing (MMT) scores of each muscle were slightly increased after the HAL intervention for Case 2(tibialis anterior, from 2 to 2+; gastrocnemius muscles, from 2- to 2; extensor digitorum longus, and extensor hallucis longus, from 1 to 3). The MMT scores were also slightly increased except for gastrocnemius muscle for Case 3 (tibialis anterior, extensor digitorum longus, and extensor hallucis longus, from 2- to 2). These two patients demonstrated voluntary muscle contractions and nerve signals in the CMAP before the HAL training. Even though the amplitude of CMAPs was low, the HAL training may provide voluntary ankle joint movements by reducing the antagonistic muscle contraction via computer processing. The HAL training may enhance muscle movement and coordination through motor learning feedback.

A biologically active lipid, thromboxane, as a regulator of angiogenesis and lymphangiogenesis.

Thromboxane (TX) and prostaglandins are metabolites of arachidonic acid, a twenty-carbon unsaturated fatty acid, and have a variety of actions that are exerted via specific receptors. Angiogenesis is defined as the formation of new blood vessels from pre-existing vascular beds and is a critical component of pathological conditions, including inflammation and cancer. Lymphatic vessels play crucial roles in the regulation of interstitial fluid, immune surveillance, and the absorption of dietary fat from the intestine; and they are also involved in the pathogenesis of various diseases. Similar to angiogenesis, lymphangiogenesis, the formation of new lymphatic vessels, is a critical component of pathological conditions. The TP-dependent accumulation of platelets in microvessels has been reported to enhance angiogenesis under pathological conditions. Although the roles of some growth factors and cytokines in angiogenesis and lymphangiogenesis have been well characterized, accumulating evidence suggests that TX induces the production of proangiogenic and prolymphangiogenic factors through the activation of adenylate cyclase, and upregulates angiogenesis and lymphangiogenesis under disease conditions. In this review, we discuss the role of TX as a regulator of angiogenesis and lymphangiogenesis, and its emerging importance as a therapeutic target.

Strong Polarization of a J=1/2 to 1/2 Transition Arising from Unexpectedly Large Quantum Interference.

We experimentally show that the 1s^{2}2s^{2}2p_{1/2}-1s2s^{2}2p_{1/2}^{2} transition in Pb^{77+} emitted in dielectronic recombination of Pb^{78+} is strongly polarized, although it is an intrinsically unpolarized J=1/2 to 1/2 transition. This unanticipated polarization is shown to be due to quantum interference with radiative recombination. The interference effect has been studied on an asymmetric resonance profile but has never been studied on polarization. In this Letter, we show that the effect on polarization can arise from a different cross term than that responsible for asymmetry, resulting in unexpectedly large polarization even for a nearly symmetric resonance suggesting a small interference.

Emergence of carbapenem-resistant Pseudomonas alcaligenes and Pseudomonas paralcaligenes clinical isolates with plasmids harbouring bla IMP-1 in Japan.

Introduction. The emergence of carbapenem-resistant Pseudomonas species producing metallo-ß-lactamase (MBL) has become a serious medical problem worldwide. IMP-type MBL was firstly detected in 1991 in Japan. Since then, it has become one of the most prevalent types of MBLs.Hypothesis/Gap statement. Avirulent species of Pseudomonas, such as Pseudomonas alcaligenes, function as reservoirs of drug resistance-associated genes encoding carbapenemases in clinical settings.Methodology. Active surveillance for carbapenem-resistant Gram-negative pathogens was conducted in 2019 at a hospital in Tokyo, Japan. Of the 543 samples screened for carbapenem-resistant isolates, 2 were species of Pseudomonas. One was from a stool sample from a medical staff member, and the other was from a stool sample from a hospitalized patient.Results. Whole-genome sequencing showed that the former isolate was a strain of P. alcaligenes, and the latter was a strain of Pseudomonas paralcaligenes, a species close to P. alcaligenes. Both isolates were resistant to all carbapenems and harboured bla IMP-1 genes encoding IMP-1 MBL, which conferred resistance to carbapenems. The bla IMP-1 genes of P. alcaligenes and P. paralcaligenes were located on the plasmids, pMRCP2, 323125 bp in size, and pMRCP1333, 16592 bp in size, respectively. The sequence of 82 % of pMRCP2 was 92 % similar to the sequence of a plasmid of P. aeruginosa PA83, whereas the sequence of 79 % of pMRCP1333 was >95 % similar to the sequence of a plasmid of Achromobacter xylosoxidans FDAARGOS 162. The genomic environments surrounding the bla IMP-1 of pMRCP2 and pMRCP1333 differed completely from each other.Conclusions. These results indicate that the two isolates acquired bla IMP-1 from different sources and that P. alcaligenes and P. paralcaligenes function as vectors and reservoirs of carbapenem-resistant genes in hospitals.

Pseudomonas paralcaligenes sp. nov., isolated from a hospitalized patient.

A Gram-stain-negative, aerobic, rod-shaped, non-endospore-forming bacterium, designated as strain MRCP1333T, was isolated from a faecal sample from a hospital patient in Japan. MRCP1333T grew at temperatures of 15-40 °C (optimum 25-35 °C), with 1.0-3.0 % (w/v, 171-513 mM) NaCl [optimum 1-2 % (w/v), 171-342 mM], and at pH 6.0-9.5 (optimum pH 7.0-8.0). The results of phylogenetic analysis based on the sequences of the 16S rRNA gene and the 53 genes encoding the bacterial ribosome protein subunits indicated that MRCP1333T represented a member of the Pseudomonas aeruginosa group, most closely related to Pseudomonas alcaligenes. Whole-genome comparisons, using average nucleotide identity, digital DNA-DNA hybridization and average amino acid identity, confirmed that MRCP1333T represented a distinct species in the P. aeruginosa group. Phenotypic characterization tests demonstrated utilization by this strain of citrate, glycerol, and d-malic acid, the ability to reduce nitrite to nitrogen and the ability of this strain to grow in the presence of minocycline and tetrazolium blue, distinguishing this strain from P. alcaligenes and other closely related species of the P. aeruginosa group. The major fatty acids of MRCP1333T were summed feature 8 (C18 : 1ω7c/C18 : 1ω6c; 38.4 %), summed feature 3 (C16 : 1ω7c/C16 : 1ω6c; 21.1 %) and C16 : 0 (20.6 %). The DNA G+C content of MRCP1333T was 66.5 mol%. Genetic and phenotypic evidence indicated that MRCP1333T should be classified as representing a novel species, for which the name Pseudomonas paralcaligenes sp. nov. is proposed. The type strain is MRCP1333T (=LMG 32254T,=JCM 34250T).

Impact of catheter ablation on functional tricuspid regurgitation in patients with atrial fibrillation.

BACKGROUND: Atrial fibrillation (AF) plays the main role in atrial functional tricuspid regurgitation (TR). However, the effectiveness of catheter ablation (CA) for atrial functional TR together with the mechanisms of improvement of atrial functional TR have not been fully evaluated. METHODS: We retrospectively investigated consecutive 2685 patients with AF who received CA from February 2004 to December 2019 in Kyoto University Hospital, Kyoto, Japan. The current study population consisted of 2331 patients with available transthoracic echocardiographic (TTE) data before CA (2110 patients without significant TR and 221 patients with significant TR). Among the 221 patients with significant TR, there were 64 patients with functional TR and follow-up TTE at 6-18 months after CA for AF, in whom we compared echocardiographic parameters from baseline to follow-up. RESULTS: Patients with significant TR were older, and more often women, and had more persistent AF than those without significant TR. Among the 64 patients with functional TR, TR severity and TR jet area significantly improved at follow-up (TR jet area: 5.8 [4.0-7.6] cm2 to 2.1 [1.1-3.1] cm2, P < 0.001). Moreover, mitral regurgitation jet area, left atrial area, mitral valve diameter, right ventricular end-diastolic area, right atrial area, and tricuspid valve diameter decreased at follow-up. CONCLUSIONS: TR severity and jet area improved after CA in patients with AF and significant TR. The improvement of TR might be associated with reverse remodeling of the right heart.

Case report: Whole genome sequence of Clostridium perfringens JUM001 causing acute emphysematous cholecystitis.

A strain of Clostridium perfringens was isolated from the bile sample of a patient with emphysematous cholecystitis who underwent a laparoscopic cholecystectomy, followed by treatment with meropenem and recovery. Metagenomic analysis of the bile sample showed that 99.73% of the bile microbiota consisted of C. perfringens, indicating that C. perfringens JUM001 was the causative pathogen of acute emphysematous cholecystitis in this patient. Complete genome sequencing showed that C. perfringens JUM001 contained a circular chromosome of 3,231,023 bp and two circular plasmids, pJUM001-1 of 49,289 bp and pJUM001-2 of 47,855 bp. JUM001 was found to possess a typing toxin gene, plc, but no other typing toxin genes, indicating that its toxinotype is type A. The plasmids pJUM001-1 and pJUM001-2 belonged to the pCP13-like and pCW3-like families of plasmids, respectively, which are characteristic conjugative and archetypical plasmids of C. perfringens. Phylogenetic analysis showed that JUM001 was closely related to C. perfringens strain JXNC-DD isolated from a dog in China. To our knowledge, this is the first report of whole-genome sequences of a clinical isolate of C. perfringens causing acute emphysematous cholecystitis.

Modified Drug-Susceptibility Testing and Screening Culture Agar for Colistin-Susceptible Enterobacteriaceae Isolates Harboring a Mobilized Colistin Resistance Gene mcr-9.

Three isolates of the Enterobacter cloacae complex harboring mcr-9, a member of the colistin resistance mcr gene family encoded on plasmids, were susceptible to colistin, with MICs of 0.125 to 0.5 µg/mL in standard broth microdilution (BMD) tests using cation-adjusted Mueller-Hinton broth (CA-MHB) in accordance with European Committee on Antimicrobial Susceptibility Testing guidelines. In contrast, their MICs for colistin were significantly higher (4 to 128 µg/mL) when BMD tests were performed using brain-heart infusion (BHI) medium, Luria-Bertani (LB) broth, tryptic soy broth (TSB), or CA-MHB supplemented with casein, tryptonen or peptone. Colistin significantly induced mcr-9 expression in a dose-dependent manner when these mcr-9-positive isolates were cultured in BHI or CA-MHB supplemented with peptone/casein. Pretreatment of mcr-9-positive isolates and Escherichia coli DH5α harboring mcr-9 with colistin significantly increased their survival rates against LL-37, a human antimicrobial peptide. Electrospray ionization time-of-flight mass spectrometry analysis showed that a lipid A moiety of lipopolysaccharide was partially modified by phosphoethanolamine in E. coli DH5α harboring mcr-9 when treated with colistin. Of 93 clinical isolates of Enterobacteriaceae, only the mcr-9-positive isolates showed MICs to colistin that were at least 32 times higher in BHI than in CA-MHB. These mcr-9-positive isolates grew on a modified BHI agar, MCR9-JU, containing 3 µg/mL colistin. These results suggest that the BMD method using BHI is useful when performed together with the BMD method using CA-MHB to detect mcr-9-positive isolates and that MCR9-JU agar is useful in screening for Enterobacteriaceae isolates harboring mcr-9 and other colistin-resistant isolates.