Assessment of the prognosis, frequency, and isolated bacteria in ventilator-associated pneumonia among patients with severe coronavirus disease 2019 pneumonia: A single-center retrospective observational study

INTRODUCTION

Acute respiratory distress syndrome (ARDS) due to severe coronavirus disease 2019 (COVID-19) pneumonia is associated with a high incidence of ventilator-associated pneumonia (VAP). We aimed to evaluate the epidemiology of VAP associated with severe COVID-19 pneumonia.

METHODS

This retrospective observational study recruited patients with COVID-19-associated ARDS admitted to our center from April 1, 2020, to September 30, 2021. The primary outcome was the survival-to-discharge rate. The secondary outcomes were the VAP rate, time to VAP, length of ICU stay, length of ventilator support, and isolated bacteria.

RESULTS

Sixty-eight patients were included in this study; 23 developed VAP. The survival-to-discharge rate was 60.9 % in the VAP group and 84.4 % in the non-VAP group. The median time to VAP onset was 16 days. The median duration of ventilator support and of ICU stay were higher in the VAP group than in the non-VAP group. The VAP rate was 33.8 %. The most common isolated species was Stenotrophomonas maltophilia. On admission, carbapenems were used in a maximum number of cases (75 %). Furthermore, the median body mass index (BMI) was lower and the median sequential organ failure assessment (SOFA) score on admission was higher in the VAP group than in the non-VAP group.

CONCLUSIONS

The survival-to-discharge rate in VAP patients was low. Moreover, VAP patients tended to have long ICU stays, low BMI, and high SOFA scores on admission. Unusually, S. maltophilia was the most common isolated bacteria, which may be related to the frequent use of carbapenems.

Transomics2cytoscape: an automated software for interpretable 2.5-dimensional visualization of trans-omic networks

Biochemical network visualization is one of the essential technologies for mechanistic interpretation of omics data. In particular, recent advances in multi-omics measurement and analysis require the development of visualization methods that encompass multiple omics data. Visualization in 2.5 dimension (2.5D visualization), which is an isometric view of stacked X-Y planes, is a convenient way to interpret multi-omics/trans-omics data in the context of the conventional layouts of biochemical networks drawn on each of the stacked omics layers. However, 2.5D visualization of trans-omics networks is a state-of-the-art method that primarily relies on time-consuming human efforts involving manual drawing. Here, we present an R Bioconductor package 'transomics2cytoscape' for automated visualization of 2.5D trans-omics networks. We confirmed that transomics2cytoscape could be used for rapid visualization of trans-omics networks presented in published papers within a few minutes. Transomics2cytoscape allows for frequent update/redrawing of trans-omics networks in line with the progress in multi-omics/trans-omics data analysis, thereby enabling network-based interpretation of multi-omics data at each research step. The transomics2cytoscape source code is available at https://github.com/ecell/transomics2cytoscape .

Chest CT findings in severe acute respiratory distress syndrome requiring V-V ECMO: J-CARVE registry

BACKGROUND

Chest computed tomography findings are helpful for understanding the pathophysiology of severe acute respiratory distress syndrome (ARDS). However, there is no large, multicenter, chest computed tomography registry for patients requiring veno-venous extracorporeal membrane oxygenation (V-V ECMO). The aim of this study was to describe chest computed tomography findings at V-V ECMO initiation and to evaluate the association between the findings and outcomes in severe ARDS.

METHODS

This multicenter, retrospective cohort study enrolled patients with severe ARDS on V-V ECMO, who were admitted to the intensive care units of 24 hospitals in Japan between January 1, 2012, and December 31, 2022.

RESULTS

The primary outcome was 90-day in-hospital mortality. The secondary outcomes were the successful liberation from V-V ECMO and the values of static lung compliance. Among the 697 registry patients, of the 582 patients who underwent chest computed tomography at V-V ECMO initiation, 394 survived and 188 died. Multivariate Cox regression showed that traction bronchiectasis and subcutaneous emphysema increased the risk of 90-day in-hospital mortality (hazard ratio [95% confidence interval] 1.77 [1.19-2.63], p = 0.005 and 1.97 [1.02-3.79], p = 0.044, respectively). The presence of traction bronchiectasis was also associated with decreased successful liberation from V-V ECMO (odds ratio: 0.27 [0.14-0.52], p < 0.001). Lower static lung compliance was associated with some chest computed tomography findings related to changes outside of pulmonary opacity, but not with the findings related to pulmonary opacity.

CONCLUSIONS

Traction bronchiectasis and subcutaneous emphysema increased the risk of 90-day in-hospital mortality in patients with severe ARDS who required V-V ECMO.

CG02N Analyzer Accurately Measures Fibrinogen Level in Whole Blood in the Presence of Low- or High-Dose Heparin

Rapid fibrinogen (Fbg) evaluation is important in patients with massive bleeding during severe trauma and those undergoing major surgery. However, there are only a few studies on the point-of-care Fbg analyzer. In this study, we aimed to investigate the accuracy of Fbg level measured using CG02N, with whole blood contained in lithium-heparinized syringes with two different concentrations of heparin. Blood samples were collected in lithium-heparinized tubes, namely PREZA-PAK®II (low-dose heparin group [LG], 7 IU/mL) and Pro-Vent® Plus (high-dose heparin group [HG], 70.5 IU/mL). The Fbg levels in LG and HG were compared with those of citrated plasma Fbg (standard-Fbg). Strong correlations with respect to the Fbg level were observed between standard-Fbg and LG or HG (r = 0.968, p < 0.0001; r = 0.970, p < 0.0001, respectively). We demonstrated that the Fbg level in whole-blood samples was accurately assessed by CG02N and not affected by low- or high-dose heparin.

Fungal transglutaminase domain-containing proteins are involved in hyphal protection at the septal pore against wounding

Transglutaminase (TG) is a ubiquitous enzyme that crosslinks substrates. In humans, TG participates in blood clotting and wound healing. However, the functions related to the cellular protection of microbial TG are unknown. In filamentous fungi, we previously identified SppB, which contains the transglutaminase core (TGc) domain and functions in hyphal protection at the septal pore upon wounding. Here, we further analyzed the cytokinesis-related protein Cyk3 and peptide N-glycanase Png1, as both contain the TGc domain. All three proteins exhibited functional importance in wound-related hyphal protection at the septal pore. Upon wounding, SppB and AoPng1 accumulated at the septal pore, whereas AoCyk3 and AoPng1 normally localized around the septal pore. The putative Cys-His-Asp catalytic triad of SppB is conserved with the human TGc domain-containing kyphoscoliosis peptidase. Catalytic triad disruptive mutants of SppB and AoCyk3 exhibited septal pore plugging defects. Similar to other TGs, SppB underwent wound-induced truncation of the N-terminal region. Notably, TG activity was detected in vivo at the septal pore of wounded hyphae using a fluorescent-labeled substrate; however, the activity was inhibited by the TG inhibitor cystamine. Our study suggests a conserved role for TGc domain-containing proteins in wound-related protection in fungi, similar to that in humans.

Daily combined measurement of platelet count and presepsin concentration can predict in-hospital death of patients with severe coronavirus disease 2019 (COVID-19)

The purpose of this study was to classify patients with severe COVID-19 into more detailed risk groups using coagulation/fibrinolysis, inflammation/immune response, and alveolar/myocardial damage biomarkers, as well as to identify prognostic markers for these patients. These biomarkers were measured every day for eight intensive care unit days in 54 adult patients with severe COVID-19. The patients were classified into survivor (n = 40) and non-survivor (n = 14) groups. Univariate and multivariate analyses showed that the combined measurement of platelet count and presepsin concentrations may be the most valuable for predicting in-hospital death, and receiver operating characteristic curve analysis further confirmed this result (area under the curve = 0.832). Patients were consequently classified into three groups (high-, medium-, and low-risk) on the basis of their cutoff values (platelet count 53 × 10³/µL, presepsin 714 pg/mL). The Kaplan-Meier curve for 90-day survival by each group showed that the 90-day mortality rate significantly increased as risk level increased (P < 0.01 by the log-rank test). Daily combined measurement of platelet count and presepsin concentration may be useful for predicting in-hospital death and classifying patients with severe COVID-19 into more detailed risk groups.

Trace copper-mediated asexual development via a superoxide dismutase and induction of AobrlA in Aspergillus oryzae

The filamentous fungus Aspergillus oryzae, in which sexual reproduction remains to be discovered, proliferates mainly via asexual spores (conidia). Therefore, despite its industrial importance in food fermentation and recombinant protein production, breeding beneficial strains by genetic crosses is difficult. In Aspergillus flavus, which is genetically close to A. oryzae, structures known as sclerotia are formed asexually, but they are also related to sexual development. Sclerotia are observed in some A. oryzae strains, although no sclerotia formation has been reported in most strains. A better understanding of the regulatory mechanisms underlying sclerotia formation in A. oryzae may contribute to discover its sexual development. Some factors involved in sclerotia formation have been previously identified, but their regulatory mechanisms have not been well studied in A. oryzae. In this study, we found that copper strongly inhibited sclerotia formation and induced conidiation. Deletion of AobrlA encoding a core regulator of conidiation and ecdR involved in transcriptional induction of AobrlA suppressed the copper-mediated inhibition of sclerotia formation, suggesting that AobrlA induction in response to copper leads not only to conidiation but also to inhibition of sclerotia formation. In addition, deletion of the copper-dependent superoxide dismutase (SOD) gene and its copper chaperone gene partially suppressed such copper-mediated induction of conidiation and inhibition of sclerotia formation, indicating that copper regulates asexual development via the copper-dependent SOD. Taken together, our results demonstrate that copper regulates asexual development, such as sclerotia formation and conidiation, via the copper-dependent SOD and transcriptional induction of AobrlA in A. oryzae.

Identification of galactofuranose antigens such as galactomannoproteins and fungal-type galactomannan from the yellow koji fungus (Aspergillus oryzae)

Filamentous fungi belonging to the genus Aspergillus are known to possess galactomannan in their cell walls. Galactomannan is highly antigenic to humans and has been reported to be involved in the pathogenicity of pathogenic filamentous fungi, such as A. fumigatus, and in immune responses. In this study, we aimed to confirm the presence of D-galactofuranose-containing glycans and to clarify the biosynthesis of D-galactofuranose-containing glycans in Aspergillus oryzae, a yellow koji fungus. We found that the galactofuranose antigen is also present in A. oryzae. Deletion of ugmA, which encodes UDP-galactopyranose mutase in A. oryzae, suppressed mycelial elongation, suggesting that D-galactofuranose-containing glycans play an important role in cell wall integrity in A. oryzae. Proton nuclear magnetic resonance spectrometry revealed that the galactofuranose-containing sugar chain was deficient and that core mannan backbone structures were present in ΔugmA A. oryzae, indicating the presence of fungal-type galactomannan in the cell wall fraction of A. oryzae. The findings of this study provide new insights into the cell wall structure of A. oryzae, which is essential for the production of fermented foods in Japan.

The whole blood transcriptional regulation landscape in 465 COVID-19 infected samples from Japan COVID-19 Task Force

Coronavirus disease 2019 (COVID-19) is a recently-emerged infectious disease that has caused millions of deaths, where comprehensive understanding of disease mechanisms is still unestablished. In particular, studies of gene expression dynamics and regulation landscape in COVID-19 infected individuals are limited. Here, we report on a thorough analysis of whole blood RNA-seq data from 465 genotyped samples from the Japan COVID-19 Task Force, including 359 severe and 106 non-severe COVID-19 cases. We discover 1169 putative causal expression quantitative trait loci (eQTLs) including 34 possible colocalizations with biobank fine-mapping results of hematopoietic traits in a Japanese population, 1549 putative causal splice QTLs (sQTLs; e.g. two independent sQTLs at TOR1AIP1), as well as biologically interpretable trans-eQTL examples (e.g., REST and STING1), all fine-mapped at single variant resolution. We perform differential gene expression analysis to elucidate 198 genes with increased expression in severe COVID-19 cases and enriched for innate immune-related functions. Finally, we evaluate the limited but non-zero effect of COVID-19 phenotype on eQTL discovery, and highlight the presence of COVID-19 severity-interaction eQTLs (ieQTLs; e.g., CLEC4C and MYBL2). Our study provides a comprehensive catalog of whole blood regulatory variants in Japanese, as well as a reference for transcriptional landscapes in response to COVID-19 infection.

Genetic mechanisms influencing COVID-19 susceptibility are not well understood. Here, the authors analyzed whole blood RNA-seq data of 465 Japanese individuals with COVID-19, highlighting thousands of fine-mapped variants affecting expression and splicing of genes, as well as the presence of COVID-19 severity-interaction eQTLs.

Protein kinase Cα activation switches YAP1 from TEAD-mediated signaling to p73-mediated signaling

Yes-associated protein 1 (YAP1) interacts with TEAD transcription factor in the nucleus and upregulates TEAD-target genes. YAP1 is phosphorylated by large tumor suppressor (LATS) kinases, the core kinases of the Hippo pathway, at 5 serine residues and is sequestered and degraded in the cytoplasm. In human cancers with the dysfunction of the Hippo pathway, YAP1 becomes hyperactive and confers malignant properties to cancer cells. We have observed that cold shock induces protein kinase C (PKC)-mediated phosphorylation of YAP1. PKC phosphorylates YAP1 at 3 serine residues among LATS-mediate phosphorylation sites. Importantly, PKC activation recruits YAP1 to the cytoplasm even in LATS-depleted cancer cells and reduces the cooperation with TEAD. PKC activation induces promyelocytic leukemia protein-mediated SUMOylation of YAP1. SUMOylated YAP1 remains in the nucleus, binds to p73, and promotes p73-target gene transcription. Bryostatin, a natural anti-neoplastic reagent that activates PKC, induces YAP1/p73-mediated apoptosis in cancer cells. Bryostatin reverses malignant transformation caused by the depletion of LATS kinases. Therefore, bryostatin and other reagents that activate PKC are expected to control cancers with the dysfunction of the Hippo pathway.

Early recognition of sepsis-induced coagulopathy using the C2PAC index: a ratio of soluble type C lectin-like receptor 2 (sCLEC-2) level and platelet count

C-type lectin-like receptor 2 (CLEC-2) is a platelet-activated receptor expressed on the surface of platelet membranes. Soluble CLEC-2 (sCLEC-2) has been receiving attention as a predictive marker for thrombotic predisposition. The present study examined the relationship between sCLEC-2 level and degree of coagulation disorder in septic patients. Seventy septic patients were divided into the sepsis-induced disseminated intravascular coagulation (DIC) (SID) group (n = 44) and non-SID group (n = 26). The sCLEC-2 levels were compared between the two groups. Because we suspected that the sCLEC-2 level was affected by the platelet count, we calculated the sCLEC-2/platelet count ratio (C2PAC index). We further divided septic patients into four groups using the Japanese Association for Acute Medicine (JAAM) DIC scoring system (DIC scores: 0-1, 2-3, 4-5, and 6-8). The C2PAC index was significantly higher in the SID group (2.6 ± 1.7) compared with the non-SID group (1.2 ± 0.5) (P < .001). The C2PAC indexes in the four JAAM DIC score groups were 0.9 ± 0.3, 1.1 ± 0.3, 1.7 ± 0.7, and 3.6 ± 1.0, respectively, and this index increased significantly as the DIC score increased (P < .001). According to the receiver-operating curve analysis, the area under the curve (AUC) and optimal cutoff value for the diagnosis of SID were 0.8051 and 1.4 (sensitivity, 75.0%; specificity, 76.9%), respectively. When the C2PAC index and D-dimer level, one of the main fibrinolytic markers, were selected as predictive markers for SID diagnosis in stepwise multiple logistic regression analysis, it was possible to diagnose SID with a high probability (AUC, 0.9528; sensitivity, 0.9545; specificity, 0.8846). The C2PAC index is a useful predictor of SID progression and diagnosis in septic patients.

Meta-analysis of transcriptional regulatory networks for lipid metabolism in neural cells from schizophrenia patients based on an open-source intelligence approach

There have been a number of reports about the transcriptional regulatory networks in schizophrenia. However, most of these studies were based on a specific transcription factor or a single dataset, an approach that is inadequate to understand the diverse etiology and underlying common characteristics of schizophrenia. Here we reconstructed and compared the transcriptional regulatory network for lipid metabolism enzymes using 15 public transcriptome datasets of neural cells from schizophrenia patients. Since many of the well-known schizophrenia-related SNPs are in enhancers, we reconstructed a network including enhancer-dependent regulation and found that 53.3 % of the total number of edges (7,577 pairs) involved regulation via enhancers. By examining multiple datasets, we found common and unique transcriptional modes of regulation. Furthermore, enrichment analysis of SNPs that were connected with genes in the transcriptional regulatory networks by eQTL suggested an association with hematological cell counts and some other traits/diseases, whose relationship to schizophrenia was either not or insufficiently reported in previous studies. Based on these results, we suggest that in future studies on schizophrenia, information on genotype, comorbidities and hematological cell counts should be included, along with the transcriptome, for a more detailed genetic stratification and mechanistic exploration of schizophrenia.

Characterization of mouse embryonic fibroblasts derived from Rassf6 knockout mice shows the implication of Rassf6 in the regulation of NF-κB signaling

RASSF6 is a member of the tumor suppressor Ras association domain family (RASSF) proteins. We have reported using human cancer cell lines that RASSF6 induces apoptosis and cell cycle arrest via p53 and plays tumor suppressive roles. In this study, we generated Rassf6 knockout mice by CRISPR/Cas technology. Contrary to our expectation, Rassf6 knockout mice were apparently healthy. However, Rassf6-null mouse embryonic fibroblasts (MEF) were resistant against ultraviolet (UV)-induced apoptosis/cell cycle arrest and senescence. UV-induced p53-target gene expression was compromised, and DNA repair was delayed in Rassf6-null MEF. More importantly, KRAS active mutant promoted the colony formation of Rassf6-null MEF but not the wild-type MEF. RNA sequencing analysis showed that NF-κB signaling was enhanced in Rassf6-null MEF. Consistently, 7,12-dimethylbenz(a)anthracene (DMBA) induced skin inflammation in Rassf6 knockout mice more remarkably than in the wild-type mice. Hence, Rassf6 deficiency not only compromises p53 function but also enhances NF-κB signaling to lead to oncogenesis.

Downregulation of the ypdA Gene Encoding an Intermediate of His-Asp Phosphorelay Signaling in Aspergillus nidulans Induces the Same Cellular Effects as the Phenylpyrrole Fungicide Fludioxonil

Many eukaryotic histidine-to-aspartate (His-Asp) phosphorelay systems consist of three types of signal transducers: a His-kinase (HK), a response regulator (RR), and a histidine-containing phosphotransfer intermediate (HPt). In general, the HPt acts as an intermediate between the HK and the RR and is indispensable for inducing appropriate responses to environmental stresses. In a previous study, we attempted but were unable to obtain deletion mutants of the ypdA gene in order to characterize its function in the filamentous fungus Aspergillus nidulans. In the present study, we constructed the CypdA strain in which ypdA expression is conditionally regulated by the A. nidulans alcA promoter. We constructed CypdA strains with RR gene disruptions (CypdA-sskAΔ, CypdA-srrAΔ, and CypdA-sskAΔsrrAΔ). Suppression of YpdA induced by ypdA downregulation activated the downstream HogA mitogen-activated protein kinase cascade. YpdA suppression caused severe growth defects and abnormal hyphae, with features such as enhanced septation, a decrease in number of nuclei, nuclear fragmentation, and hypertrophy of vacuoles, both regulated in an SskA-dependent manner. Fludioxonil treatment caused the same cellular responses as ypdA suppression. The growth-inhibitory effects of fludioxonil and the lethality caused by ypdA downregulation may be caused by the same or similar mechanisms and to be dependent on both the SskA and SrrA pathways.

Coronavirus disease (COVID-19) associated delayed-onset fulminant myocarditis in patient with a history of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection

A healthy 35-year-old man was admitted to a rural hospital with coronavirus disease (COVID-19). During 14 days of hospitalization, he had no symptoms and was not given supplemental oxygen. About 3 weeks after discharge, he was re-admitted to the same hospital with new-onset continuous fever and general weakness. At the time of his second admission, severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) RT-PCR was performed on a retro-nasal swab and the result was negative. Four days after admission, the patient was transferred to our intensive care unit (ICU) following deterioration of his respiratory and haemodynamic conditions, where he received mechanical ventilation, intra-aortic balloon pumping, and veno-arterial extracorporeal membrane oxygenation. A nasopharyngeal swab was obtained again at ICU admission, but RT-PCR was negative for SARS-CoV-2. All antibody titres measured against other viruses were low. Blood cultures were negative, and no bacteria were observed in sputum samples. However, SARS-CoV-2 RNA was detected by RT-PCR from sections obtained by myocardial biopsy. The patient's final diagnosis was delayed-onset SARS-CoV-2-induced fulminant myocarditis (FM). We strongly suggested that one of the proposed mechanisms of COVID-19-related myocardial injury will be the direct invasion of SARS-CoV-2 into cardiomyocytes even if delayed-onset. And this is the first case of delayed-onset FM in which diagnosis of active myocarditis was proven by pathological examination following endomyocardial biopsy and SARS-CoV-2 was detected in the myocardium by RT-PCR.

SARS-CoV-2 is localized in cardiomyocytes: a post-mortem biopsy case

A 72-year-old patient was admitted to the intensive care unit due to acute respiratory distress syndrome caused by COVID-19. On day 20, the patient experienced shock. The electrocardiogram showed ST segment elevation in leads V3–V6 and severe left ventricular dysfunction with an ejection fraction of 35%–40%. The left ventricle showed basal hypokinesis and apical akinesis, while the creatine kinase level was normal, indicating Takotsubo cardiomyopathy. On day 24, the patient died of multiple organ failure. In post-mortem biopsy, SARS-CoV-2 antigen was detected in cardiomyocytes by immunostaining. Moreover, SARS-CoV-2 RNA was detected in heart tissue. We need to further analyse the direct link between SARS-CoV-2 and cardiomyocytes.

Retraction notice to "Doublecortin-like kinase 1 compromises DNA repair and induces chromosomal instability" [BBREP 16C (2018) 130-137]

[This retracts the article DOI: 10.1016/j.bbrep.2018.10.014.].

Validating plasminogen activator inhibitor-1 as a poor prognostic factor in sepsis

Aim

Our previous report indicated that plasminogen activator inhibitor‐1 (PAI‐1) levels of ≥83 ng/mL in patients with sepsis tended to be associated with disseminated intravascular coagulation (DIC), suppressed fibrinolysis, multiple organ dysfunction, and mortality. Therefore, the present study aimed to validate whether 83 ng/mL was a useful cut‐off value for using PAI‐1 levels to predict a poor prognosis in sepsis.

Methods

Patients with sepsis were included in this single‐center retrospective study. The patients were classified as having high or low PAI‐1 values (<83 ng/mL versus ≥83 ng/mL), and were compared in terms of their pre‐DIC state, intensive care unit‐free days, continuous renal replacement therapy‐free days, ventilator‐free days, catecholamine‐free days, and 28‐day survival rate.

Results

The high PAI‐1 group included 61 patients (54%) and the low PAI‐1 group included 52 patients (46%). The high PAI‐1 group had significantly higher frequencies of a pre‐DIC state within 1 week (P = 0.009). There was no significant difference in ventilator‐free days. However, the high PAI‐1 group had significantly lower values for intensive care unit‐free days (P = 0.01), continuous renal replacement therapy‐free days (P = 0.02), and catecholamine‐free days (P = 0.02). The high PAI‐1 group also had a significantly lower 28‐day survival rate based on the Kaplan–Meier analysis (log–rank, P = 0.03).

Conclusion

Patients with sepsis and PAI‐1 levels of ≥83 ng/mL had elevated risks of coagulopathy, organ failure, and mortality. Thus, these results suggest that 83 ng/mL could be a useful cut‐off value for prognostication based on PAI‐1 levels in this setting.

Assessment of suitable antihypertensive therapies: Combination with high-dose amlodipine/irbesartan vs triple combination with amlodipine/irbesartan/indapamide (ASAHI-AI study)

Angiotensin receptor blockers (ARBs) plus calcium channel blockers (CCBs) are a widely used combination therapy for hypertensive patients. In order to determine which combination was better as the next-step therapy for standard-dose combination of ARBs and CCBs, a combination with high-dose CCBs or a triple combination with diuretics, the authors conducted a prospective, randomized, open-label trial to determine which of the following combination is better as the next-step treatment: a combination with high-dose CCBs or a triple combination with diuretics. Hypertensive outpatients who did not achieve their target blood pressure (BP) with usual dosages of ARBs and amlodipine 5 mg were randomly assigned to treatment with irbesartan 100 mg/amlodipine 10 mg (Group 1: n = 48) or indapamide 1 mg in addition to ARBs plus amlodipine 5 mg (Group 2: n = 46). The primary end point was changes in the systolic BP (SBP) and diastolic BP (DBP) after the 12-week treatment period, while secondary end points were changes in BP after the 24-week treatment period and laboratory values. At 12 weeks, the SBP/DBP significantly decreased from 152.1/83.4 mm Hg to 131.5/76.1 mm Hg in Group 1 and 153.9/82.1 mm Hg to 132.7/75.9 mm Hg in Group 2. Although both groups produced a similar efficacy in reducing the SBP/DBP (-19.2/-9.2 mm Hg in Group 1 and -21.6/-8.8 mm Hg in Group 2; SBP P = .378, DBP P = .825), high-dose CCBs combined with ARBs controlled hypertension without elevation of serum uric acid. These results will provide new evidence for selecting optimal combination therapies for uncontrolled hypertensive patients.

The RAS-interacting chaperone UNC119 drives the RASSF6-MDM2-p53 axis and antagonizes RAS-mediated malignant transformation

The gene encoding the proto-oncogene GTPase RAS is frequently mutated in human cancers. Mutated RAS proteins trigger antiapoptotic and cell-proliferative signals and lead to oncogenesis. However, RAS also induces apoptosis and senescence, which may contribute to the eradication of cells with RAS mutations. We previously reported that Ras association domain family member 6 (RASSF6) binds MDM2 and stabilizes the tumor suppressor p53 and that the active form of KRAS promotes the interaction between RASSF6 and MDM2. We also reported that Unc-119 lipid-binding chaperone (UNC119A), a chaperone of myristoylated proteins, interacts with RASSF6 and regulates RASSF6-mediated apoptosis. In this study, using several human cancer cell lines, quantitative RT-PCR, RNAi-based gene silencing, and immunoprecipitation/-fluorescence and cell biology assays, we report that UNC119A interacts with the active form of KRAS and that the C-terminal modification of KRAS is required for this interaction. We also noted that the hydrophobic pocket of UNC119A, which binds the myristoylated peptides, is not involved in the interaction. We observed that UNC119A promotes the binding of KRAS to RASSF6, enhances the interaction between RASSF6 and MDM2, and induces apoptosis. Conversely, UNC119A silencing promoted soft-agar colony formation, migration, and invasiveness in KRAS-mutated cancer cells. We conclude that UNC119A promotes KRAS-mediated p53-dependent apoptosis via RASSF6 and may play a tumor-suppressive role in cells with KRAS mutations.

Inter-strain expression of sequence-diverse HET domain genes severely inhibits growth of Aspergillus oryzae

In the Pezizomycotina (filamentous ascomycete) species, genes that encode proteins with an HET domain (Pfam: PF06985) are reportedly involved in heterokaryon incompatibility (HI) in which cell death or growth defects are induced after fusion of cells that are genetically incompatible owing to diversities in their nucleotide sequence. HET domain genes are commonly found in Pezizomycotina genomes and are functionally characterized in only a few species. Here, we compared 44 HET domain genes between an incompatible strain pair of Aspergillus oryzae RIB40 and RIB128 and performed inter-strain expression of 37 sequence-diverse genes for mimicking HI. Four HET domain genes were identified to cause severe growth inhibition in a strain- or sequence-specific manner. Furthermore, SNPs responsible for the inhibition of cell growth were identified. This study provides an important insight into the physiological significance of sequence diversity of HET domain genes and their potential functions in HI of A. oryzae.

Outcomes in patients with infections and augmented renal clearance: A multicenter retrospective study

Recently, augmented renal clearance (ARC), which accelerates glomerular filtration of renally eliminated drugs thereby reducing the systemic exposure to these drugs, has started to receive attention. However, the clinical features associated with ARC are still not well understood, especially in the Japanese population. This study aimed to evaluate the clinical characteristics and outcomes of ARC patients with infections in Japanese intensive care unit (ICU) settings. We conducted a retrospective observational study from April 2013 to May 2017 at two tertiary level ICUs in Japan, which included 280 patients with infections (median age 74 years; interquartile range, 64–83 years). We evaluated the estimated glomerular filtration rate (eGFR) at ICU admission using the Japanese equation, and ARC was defined as eGFR >130 mL/min/1.73 m². Multivariable logistic regression analysis was performed to identify the independent risk factors for ARC and to determine if it was a predictor of ICU mortality. In addition, a receiver operating curve (ROC) analysis was performed, and the area under the ROC (AUROC) was determined to examine the significant variables that predict ARC. In total, 19 patients (6.8%) manifested ARC. Multivariable logistic regression analysis identified younger age as an independent risk factor for ARC (odds ratio [OR], 0.94; 95% confidence interval [CI], 0.91–0.96). However, ARC was not found to be a predictor of ICU mortality (OR, 0.57; 95% CI, 0.11–2.92). In addition, the AUROC of age was 0.79 (95% CI, 0.68–0.91), and the optimal cut off age for ARC was ≤63 years (sensitivity, 68.4%; specificity, 78.9%). The incidence of ARC was, therefore, low among patients with infections in the Japanese ICUs. Although younger age was associated with the incidence of ARC, it was not an independent predictor of ICU mortality.

Doublecortin-like kinase 1 compromises DNA repair and induces chromosomal instability

Doublecortin-like kinase 1 (DCLK1) is a serine/threonine-kinase with two doublecortin (DCX) domains. DCLK1 is associated with microtubules via DCX domains and regulates microtubule polymerization. DCLK1 is known to be expressed in cancer stem cells and provides cancer cells with tumor-initiating capacity. Accumulating clinical evidence supports that DCLK1 is associated with tumor aggressiveness and is an important prognostic marker in various human cancers. However, the mechanism, by which DCLK1 causes oncogenesis, is not yet elucidated. In this study, we showed that DCLK1 empowers human mammary epithelial MCF10A cells to form spheres under floating condition in serum-free medium, which are reminiscent of mammospheres formed by mammary epithelial stem cells. We demonstrated that DCLK1 causes chromatin instability in MCF10A cells. DCLK1 impairs DNA repairs in human colon cancer HCT116 and lung cancer H1299 cells. The kinase-negative DCLK1 mutant and the mutant that is not associated with microtubules compromise DNA repair. In conclusion, DCLK1 interferes with DNA repair and induces tumorigenesis through genomic instability and this function is independent of the kinase activity and the regulation of microtubules.

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Doublecortin-like kinase 1 (DCLK1) confers stemness to cancer cells.

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Mammary epithelial cells expressing DCLK1 form spheres under floating condition.

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DCLK1 causes robust chromosomal abnormalities in mammary epithelial cells.

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DCLK1 impairs DNA repair in cancer cells.

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The kinase-negative DCLK1 shows similar effects.

UNC119 is a binding partner of tumor suppressor Ras-association domain family 6 and induces apoptosis and cell cycle arrest by MDM2 and p53

Ras-association domain family 6 (RASSF6) is a tumor suppressor that interacts with MDM2 and stabilizes p53. Caenorhabditis elegans unc-119 encodes a protein that is required for normal development of the nervous system. Humans have 2 unc-119 homologues, UNC119 and UNC119B. We have identified UNC119 as a RASSF6-interacting protein. UNC119 promotes the interaction between RASSF6 and MDM2 and stabilizes p53. Thus, UNC119 induces apoptosis by RASSF6 and p53. UNC119 depletion impairs DNA repair after DNA damage and results in polyploid cell generation. These findings support that UNC119 is a regulator of the RASSF6-MDM2-p53 axis and functions as a tumor suppressor.

BCL-XL binds and antagonizes RASSF6 tumor suppressor to suppress p53 expression

RASSF6, a member of the tumor suppressor Ras-association domain family proteins, induces apoptosis in the caspase-dependent and caspase-independent manners. RASSF6 interacts with MDM2 and stabilizes p53. BCL-XL is a prosurvival member of BCL-2 family proteins. BCL-XL directly inhibits proapoptotic BAX and BAK. BCL-XL also traps tBID, a proapoptotic activator BH3-only protein, and sequesters p53. In addition, BCL-XL regulates the mitochondrial membrane permeability via voltage-dependent anion channel. In these manners, BCL-XL plays an antiapoptotic role. We report the interaction of BCL-XL with RASSF6. BCL-XL inhibits the interaction between RASSF6 and MDM2 and suppresses p53 expression. Consequently, BCL-XL antagonizes RASSF6-mediated apoptosis. Thus, the inhibition of RASSF6-mediated apoptosis also underlies the prosurvival role of BCL-XL.

Application of Split-GFP Reassembly Assay to Study Myogenesis and Myofusion In Vitro

Green fluorescent protein (GFP) is composed of 11 β-strands, and loses GFP signals, when divided into the N-terminal ten β-strands (GFP1-10) and the C-terminal last β-strand (GFP11). However, when GFP1-10 and GFP11 encounter, they reassemble into the fluorescent GFP. We expressed GFP1-10 and blasticidin resistance gene product-fused GFP11 (BSR-GFP11) in C2C12 cells. Both the cell lines do not show GFP but when they undergo myogenesis and myofusion, GFP1-10 and BSR-GFP11 form the fluorescent complex in multi-nuclear myotubes, so that GFP signals reflect myogenesis and myofusion.

Validation of chemical compound library screening for transcriptional co-activator with PDZ-binding motif inhibitors using GFP-fused transcriptional co-activator with PDZ-binding motif

Transcriptional co-activator with PDZ-binding motif (TAZ) plays versatile roles in cell proliferation and differentiation. It is phosphorylated by large tumor suppressor kinases, the core kinases of the tumor-suppressive Hippo pathway. Phosphorylation induces the cytoplasmic accumulation of TAZ and its degradation. In human cancers, the deregulation of the Hippo pathway and gene amplification enhance TAZ activity. TAZ interacts with TEA domain family members (TEAD), and upregulates genes implicated in epithelial-mesenchymal transition. It also confers stemness to cancer cells. Thus, TAZ activation provides cancer cells with malignant properties and worsens the clinical prognosis. Therefore, TAZ attracts attention as a therapeutic target in cancer therapy. We applied 18 606 small chemical compounds to human osteosarcoma U2OS cells expressing GFP-fused TAZ (GFP-TAZ), monitored the subcellular localization of GFP-TAZ, and selected 33 compounds that shifted GFP-TAZ to the cytoplasm. Unexpectedly, only a limited number of compounds suppressed TAZ-mediated enhancement of TEAD-responsive reporter activity. Moreover, the compounds that weakened TEAD reporter activity did not necessarily decrease the unphosphorylated TAZ. In this study, we focused on three compounds that decreased both TEAD reporter activity and unphosphorylated TAZ, and treated several human cancer cells with these compounds. One compound did not show a remarkable effect, whereas the other two compounds compromised the cell viability in certain cancer cells. In conclusion, the GFP-TAZ-based assay can be used as the first screening for compounds that inhibit TAZ and show anticancer properties. To develop anticancer drugs, we need additional assays to select the compounds.

AoRim15 is involved in conidial stress tolerance, conidiation and sclerotia formation in the filamentous fungus Aspergillus oryzae

The serine-threonine kinase Rim15p is a master regulator of stress signaling and is required for stress tolerance and sexual sporulation in the yeast Saccharomyces cerevisiae. However, in filamentous fungi that reproduce asexually via conidiation, the physiological function of Rim15p homologs has not been extensively analyzed. Here, we functionally characterized the protein homolog of Rim15p in the filamentous fungus Aspergillus oryzae, by deleting and overexpressing the corresponding Aorim15 gene and examining the role of this protein in stress tolerance and development. Deletion of Aorim15 resulted in an increase in the sensitivity of conidia to oxidative and heat stresses, whereas conidia of the Aorim15 overexpressing strain were more resistant to these stresses. These results indicated that AoRim15 functions in stress tolerance, similar to S. cerevisiae Rim15p. Phenotypic analysis revealed that conidiation was markedly reduced by overexpression of Aorim15 in A. oryzae, and was completely abolished in the deletion strain. In addition, the formation of sclerotia, which is another type of developmental structure in filamentous fungi, was decreased by the deletion of Aorim15, whereas Aorim15 overexpression increased the number of sclerotia. These results indicated that AoRim15 is a positive regulator of sclerotia formation and that overexpression of AoRim15 shifts the developmental balance from conidiation towards sclerotia formation. Collectively, we demonstrated that AoRim15 is involved in the stress tolerance of conidia and differentially regulates between the two developmental fates of conidiation and sclerotia formation.

A cell-based screening for TAZ activators identifies ethacridine, a widely used antiseptic and abortifacient, as a compound that promotes dephosphorylation of TAZ and inhibits adipogenesis in C3H10T1/2 cells

Transcriptional co-activator with PSD-95/Dlg-A/ZO-1 (PDZ)-binding motif (TAZ) regulates in cell proliferation and differentiation. In mesenchymal stem cells it promotes osteogenesis and myogenesis, and suppresses adipogenesis. TAZ activators are expected to prevent osteoporosis, obesity and muscle atrophy. TAZ activation induces epithelial-mesenchymal transition, confers stemness to cancer cells and leads to poor clinical prognosis in cancer patients. In this point of view, TAZ inhibitors should contribute to cancer therapy. Thus, TAZ attracts attention as a two-faced drug target. We screened for TAZ modulators by using human lung cancer A549 cells expressing the fluorescent reporter. Through this assay, we obtained TAZ activator candidates. We unexpectedly found that ethacridine, a widely used antiseptic and abortifacient, enhances the interaction of TAZ and protein phosphatases and increases unphosphorylated and nuclear TAZ. Ethacridine inhibits adipogenesis in mesenchymal C3H10T1/2 cells through the activation of TAZ. This finding suggests that ethacridine is a bona fide TAZ activator and supports that our assay is useful to discover TAZ activators.

Establishment of a new method to quantitatively evaluate hyphal fusion ability in Aspergillus oryzae

Hyphal fusion is involved in the formation of an interconnected colony in filamentous fungi, and it is the first process in sexual/parasexual reproduction. However, it was difficult to evaluate hyphal fusion efficiency due to the low frequency in Aspergillus oryzae in spite of its industrial significance. Here, we established a method to quantitatively evaluate the hyphal fusion ability of A. oryzae with mixed culture of two different auxotrophic strains, where the ratio of heterokaryotic conidia growing without the auxotrophic requirements reflects the hyphal fusion efficiency. By employing this method, it was demonstrated that AoSO and AoFus3 are required for hyphal fusion, and that hyphal fusion efficiency of A. oryzae was increased by depleting nitrogen source, including large amounts of carbon source, and adjusting pH to 7.0.

Efficient formation of heterokaryotic sclerotia in the filamentous fungus Aspergillus oryzae

Heterokaryon formation by hyphal fusion occurs during a sexual/parasexual cycle in filamentous fungi, and therefore, it is biotechnologically important for crossbreeding. In the industrial filamentous fungus Aspergillus oryzae, a parasexual cycle has been reported, and it was recently suggested that sexual reproduction should be possible. However, as A. oryzae enters into hyphal fusion with a much lower frequency than Neurospora crassa, the process of heterokaryon formation has not been extensively characterized in A. oryzae. Here, we developed a detection system for heterokaryon formation by expressing red or green fluorescent proteins in nuclei and conferring uridine/uracil or adenine auxotrophy to MAT1-1 and MAT1-2 strains of A. oryzae. The heterokaryon formation of A. oryzae was investigated in paired culture using the genetically modified strains. No sclerotial formation was observed in the hyphal contact regions of the two strains with the same auxotrophy, whereas numerous sclerotia were formed between the strains with different auxotrophies. In most of the formed sclerotia, the uridine/uracil and adenine auxotrophies were complemented, and both red and green fluorescence were detected, indicating that heterokaryotic fusants were formed by hyphal fusion before or during sclerotial formation. Moreover, overexpressing the sclR gene, which encodes a transcription factor promoting sclerotial formation, increased the number of heterokaryotic sclerotia formed between the two auxotrophic strains. Notably, these effects in sclerotial formation of heterokaryotic fusants were observed independently of the mating type pairing combinations. Taken together, these findings demonstrated that paring of different auxotrophs and sclR overexpression promote the formation of heterokaryotic sclerotia in A. oryzae.

The RASSF6 tumor suppressor protein regulates apoptosis and the cell cycle via MDM2 protein and p53 protein

Ras association domain family (RASSF) 6 is a member of the C-terminal RASSF proteins such as RASSF1A and RASSF3. RASSF6 is involved in apoptosis in various cells under miscellaneous conditions, but it remains to be clarified how RASSF6 exerts tumor-suppressive roles. We reported previously that RASSF3 facilitates the degradation of MDM2, a major E3 ligase of p53, and stabilizes p53 to function as a tumor suppressor. In this study, we demonstrate that RASSF6 overexpression induces G1/S arrest in p53-positive cells. Its depletion prevents UV- and VP-16-induced apoptosis and G1/S arrest in HCT116 and U2OS cells. RASSF6-induced apoptosis partially depends on p53. RASSF6 binds MDM2 and facilitates its ubiquitination. RASSF6 depletion blocks the increase of p53 in response to UV exposure and up-regulation of p53 target genes. RASSF6 depletion delays DNA repair in UV- and VP-16-treated cells and increases polyploid cells after VP-16 treatment. These findings indicate that RASSF6 stabilizes p53, regulates apoptosis and the cell cycle, and functions as a tumor suppressor. Together with the previous reports regarding RASSF1A and RASSF3, the stabilization of p53 may be the common function of the C-terminal RASSF proteins.

Aspergillus oryzae AoSO is a novel component of stress granules upon heat stress in filamentous fungi

Stress granules are a type of cytoplasmic messenger ribonucleoprotein (mRNP) granule formed in response to the inhibition of translation initiation, which typically occurs when cells are exposed to stress. Stress granules are conserved in eukaryotes; however, in filamentous fungi, including Aspergillus oryzae, stress granules have not yet been defined. For this reason, here we investigated the formation and localization of stress granules in A. oryzae cells exposed to various stresses using an EGFP fusion protein of AoPab1, a homolog of Saccharomyces cerevisiae Pab1p, as a stress granule marker. Localization analysis showed that AoPab1 was evenly distributed throughout the cytoplasm under normal growth conditions, and accumulated as cytoplasmic foci mainly at the hyphal tip in response to stress. AoSO, a homolog of Neurospora crassa SO, which is necessary for hyphal fusion, colocalized with stress granules in cells exposed to heat stress. The formation of cytoplasmic foci of AoSO was blocked by treatment with cycloheximide, a known inhibitor of stress granule formation. Deletion of the Aoso gene had effects on the formation and localization of stress granules in response to heat stress. Our results suggest that AoSO is a novel component of stress granules specific to filamentous fungi.

The authors would specially like to thank Hiroyuki Nakano and Kei Saeki for generously providing experimental and insightful opinions.

Enhanced production of bovine chymosin by autophagy deficiency in the filamentous fungus Aspergillus oryzae

Aspergillus oryzae has been utilized as a host for heterologous protein production because of its high protein secretory capacity and food-safety properties. However, A. oryzae often produces lower-than-expected yields of target heterologous proteins due to various underlying mechanisms, including degradation processes such as autophagy, which may be a significant bottleneck for protein production. In the present study, we examined the production of heterologous protein in several autophagy (Aoatg) gene disruptants of A. oryzae. We transformed A. oryzae gene disruptants of Aoatg1, Aoatg13, Aoatg4, Aoatg8, or Aoatg15, with a bovine chymosin (CHY) expression construct and found that the production levels of CHY increased up to three fold compared to the control strain. Notably, however, conidia formation by the Aoatg gene disruptants was significantly reduced. As large amounts of conidia are necessary for inoculating large-scale cultures, we also constructed Aoatg gene-conditional expression strains in which the promoter region of the Aoatg gene was replaced with the thiamine-controllable thiA promoter. Conidiation by the resultant transformants was clearly enhanced in the absence of thiamine, while autophagy remained repressed in the presence of thiamine. Moreover, these transformants displayed increased CHY productivity, which was comparable to that of the Aoatg gene disruptants. Consequently, we succeeded in the construction of A. oryzae strains capable of producing high levels of CHY due to defects in autophagy. Our finding suggests that the conditional regulation of autophagy is an effective method for increasing heterologous protein production in A. oryzae.

A newly discovered function of peroxisomes: involvement in biotin biosynthesis

In plants, peroxisomes are the organelles involved in various metabolic processes and physiological functions including β-oxidation, mobilization of seed storage lipids, photorespiration, and hormone biosynthesis. We have recently shown that, in fungi and plants, peroxisomes play a vital role in biosynthesis of biotin, an essential cofactor required for various carboxylation and decarboxylation reactions. In fungi, the mutants defective in peroxisomal protein import exhibit biotin auxotrophy. The fungal BioF protein, a 7-keto-8-aminopelargonic acid (KAPA) synthase catalyzing the conversion of pimeloyl-CoA to KAPA in biotin biosynthesis, contains the peroxisomal targeting sequence 1 (PTS1), and its peroxisomal targeting is required for biotin biosynthesis. In plants, biotin biosynthesis is essential for embryo development. We have shown that the peroxisomal targeting sequences of the BioF proteins are conserved throughout the plant kingdom, and the Arabidopsis thaliana BioF protein is indeed localized in peroxisomes. Our findings suggest that peroxisomal localization of the BioF protein is evolutionarily conserved among eukaryotes, and required for biotin biosynthesis and plant growth and development.

Rhomboid protease PARL mediates the mitochondrial membrane potential loss-induced cleavage of PGAM5

Regulated intramembrane proteolysis is a widely conserved mechanism for controlling diverse biological processes. Considering that proteolysis is irreversible, it must be precisely regulated in a context-dependent manner. Here, we show that phosphoglycerate mutase 5 (PGAM5), a mitochondrial Ser/Thr protein phosphatase, is cleaved in its N-terminal transmembrane domain in response to mitochondrial membrane potential (ΔΨ(m)) loss. This ΔΨ(m) loss-dependent cleavage of PGAM5 was mediated by presenilin-associated rhomboid-like (PARL). PARL is a mitochondrial resident rhomboid serine protease and has recently been reported to mediate the cleavage of PINK1, a mitochondrial Ser/Thr protein kinase, in healthy mitochondria with intact ΔΨ(m). Intriguingly, we found that PARL dissociated from PINK1 and reciprocally associated with PGAM5 in response to ΔΨ(m) loss. These results suggest that PARL mediates differential cleavage of PINK1 and PGAM5 depending on the health status of mitochondria. Our data provide a prototypical example of stress-dependent regulation of PARL-mediated regulated intramembrane proteolysis.

Improved heterologous protein production by a tripeptidyl peptidase gene (AosedD) disruptant of the filamentous fungus Aspergillus oryzae

Proteolytic degradation is one of the serious bottlenecks limiting the yields of heterologous protein production by Aspergillus oryzae. In this study, we selected a tripeptidyl peptidase gene AosedD (AO090166000084) as a candidate potentially degrading the heterologous protein, and performed localization analysis of the fusion protein AoSedD-EGFP in A. oryzae. As a result, the AoSedD-EGFP was observed in the septa and cell walls as well as in the culture medium, suggesting that AoSedD is a secretory enzyme. An AosedD disruptant was constructed to investigate an effect of AoSedD on the production level of heterologous proteins and protease activity. Both of the total protease and tripeptidyl peptidase activities in the culture medium of the AosedD disruptant were decreased as compared to those of the control strain. The maximum yields of recombinant bovine chymosin (CHY) and human lysozyme (HLY) produced by the AosedD disruptants showed approximately 2.9- and 1.7-fold increases, respectively, as compared to their control strains. These results suggest that AoSedD is one of the major proteases involved in the proteolytic degradation of recombinant proteins in A. oryzae.