Phosphatidic acid produced by phospholipase Dα1 and Dδ is incorporated into the internal membranes but not involved in the gene expression of RD29A in the abscisic acid signaling network in Arabidopsis thaliana

Core protein components of the abscisic acid (ABA) signaling network, pyrabactin resistance (PYR), protein phosphatases 2C (PP2C), and SNF1-related protein kinase 2 (SnRK2) are involved in the regulation of stomatal closure and gene expression downstream responses in Arabidopsis thaliana. Phosphatidic acid (PA) produced by the phospholipases Dα1 and Dδ (PLDs) in the plasma membrane has been identified as a necessary molecule in ABA-inducible stomatal closure. On the other hand, the involvement of PA in ABA-inducible gene expression has been suggested but remains a question. In this study, the involvement of PA in the ABA-inducible gene expression was examined in the model plant Arabidopsis thaliana and the canonical RD29A ABA-inducible gene that possesses a single ABA-responsive element (ABRE) in the promoter. The promoter activity and accumulation of the RD29A mRNA during ABA exposure to the plants were analyzed under conditions in which the production of PA by PLDs is abrogated through chemical and genetic modification. Changes in the subcellular localization of PA during the signal transduction were analyzed with confocal microscopy. The results obtained in this study suggest that inhibition of PA production by the PLDs does not affect the promoter activity of RD29A. PA produced by the PLDs and exogenously added PA in the plasma membrane are effectively incorporated into internal membranes to transduce the signal. However, exogenously added PA induces stomatal closure but not RD29A expression. This is because PA produced by the PLDs most likely inhibits the activity of not all but only the selected PP2C family members, the negative regulators of the RD29A promoter. This finding underscores the necessity for experimental verifications to adapt previous knowledge into a signaling network model before its construction.

High-grade pancreatic intraepithelial neoplasia diagnosed based on changes in magnetic resonance cholangiopancreatography findings: A case report

BACKGROUND

High-grade pancreatic intraepithelial neoplasia (PanIN) exhibits no mass and is not detected by any examination modalities. However, it can be diagnosed by pancreatic juice cytology from indirect findings. Most previous cases were diagnosed based on findings of a focal stricture of the main pancreatic duct (MPD) and caudal MPD dilatation and subsequent pancreatic juice cytology using endoscopic retrograde cholangiopancreatography (ERCP). We experienced a case of high-grade PanIN with an unclear MPD over a 20-mm range, but without caudal MPD dilatation on magnetic resonance cholangiopancreatography (MRCP).

CASE SUMMARY

A 60-year-old female patient underwent computed tomography for a follow-up of uterine cancer post-excision, which revealed pancreatic cysts. MRCP revealed an unclear MPD of the pancreatic body at a 20-mm length without caudal MPD dilatation. Thus, course observation was performed. After 24 mo, MRCP revealed an increased caudal MPD caliber and a larger pancreatic cyst. We performed ERCP and detected atypical cells suspected of adenocarcinoma by serial pancreatic juice aspiration cytology examination. We performed a distal pancreatectomy and obtained a histopathological diagnosis of high-grade PanIN. Pancreatic parenchyma invasion was not observed, and curative resection was achieved.

CONCLUSION

High-grade Pan-IN may cause MPD narrowing in a long range without caudal MPD dilatation.

Effects of empagliflozin on progression of chronic kidney disease: a prespecified secondary analysis from the empa-kidney trial

BACKGROUND

Sodium-glucose co-transporter-2 (SGLT2) inhibitors reduce progression of chronic kidney disease and the risk of cardiovascular morbidity and mortality in a wide range of patients. However, their effects on kidney disease progression in some patients with chronic kidney disease are unclear because few clinical kidney outcomes occurred among such patients in the completed trials. In particular, some guidelines stratify their level of recommendation about who should be treated with SGLT2 inhibitors based on diabetes status and albuminuria. We aimed to assess the effects of empagliflozin on progression of chronic kidney disease both overall and among specific types of participants in the EMPA-KIDNEY trial.

METHODS

EMPA-KIDNEY, a randomised, controlled, phase 3 trial, was conducted at 241 centres in eight countries (Canada, China, Germany, Italy, Japan, Malaysia, the UK, and the USA), and included individuals aged 18 years or older with an estimated glomerular filtration rate (eGFR) of 20 to less than 45 mL/min per 1·73 m2, or with an eGFR of 45 to less than 90 mL/min per 1·73 m2 with a urinary albumin-to-creatinine ratio (uACR) of 200 mg/g or higher. We explored the effects of 10 mg oral empagliflozin once daily versus placebo on the annualised rate of change in estimated glomerular filtration rate (eGFR slope), a tertiary outcome. We studied the acute slope (from randomisation to 2 months) and chronic slope (from 2 months onwards) separately, using shared parameter models to estimate the latter. Analyses were done in all randomly assigned participants by intention to treat. EMPA-KIDNEY is registered at ClinicalTrials.gov, NCT03594110.

FINDINGS

Between May 15, 2019, and April 16, 2021, 6609 participants were randomly assigned and then followed up for a median of 2·0 years (IQR 1·5-2·4). Prespecified subgroups of eGFR included 2282 (34·5%) participants with an eGFR of less than 30 mL/min per 1·73 m2, 2928 (44·3%) with an eGFR of 30 to less than 45 mL/min per 1·73 m2, and 1399 (21·2%) with an eGFR 45 mL/min per 1·73 m2 or higher. Prespecified subgroups of uACR included 1328 (20·1%) with a uACR of less than 30 mg/g, 1864 (28·2%) with a uACR of 30 to 300 mg/g, and 3417 (51·7%) with a uACR of more than 300 mg/g. Overall, allocation to empagliflozin caused an acute 2·12 mL/min per 1·73 m2 (95% CI 1·83-2·41) reduction in eGFR, equivalent to a 6% (5-6) dip in the first 2 months. After this, it halved the chronic slope from -2·75 to -1·37 mL/min per 1·73 m2 per year (relative difference 50%, 95% CI 42-58). The absolute and relative benefits of empagliflozin on the magnitude of the chronic slope varied significantly depending on diabetes status and baseline levels of eGFR and uACR. In particular, the absolute difference in chronic slopes was lower in patients with lower baseline uACR, but because this group progressed more slowly than those with higher uACR, this translated to a larger relative difference in chronic slopes in this group (86% [36-136] reduction in the chronic slope among those with baseline uACR <30 mg/g compared with a 29% [19-38] reduction for those with baseline uACR ≥2000 mg/g; ptrend<0·0001).

INTERPRETATION

Empagliflozin slowed the rate of progression of chronic kidney disease among all types of participant in the EMPA-KIDNEY trial, including those with little albuminuria. Albuminuria alone should not be used to determine whether to treat with an SGLT2 inhibitor.

FUNDING

Boehringer Ingelheim and Eli Lilly.

Impact of primary kidney disease on the effects of empagliflozin in patients with chronic kidney disease: secondary analyses of the EMPA-KIDNEY trial

BACKGROUND

The EMPA-KIDNEY trial showed that empagliflozin reduced the risk of the primary composite outcome of kidney disease progression or cardiovascular death in patients with chronic kidney disease mainly through slowing progression. We aimed to assess how effects of empagliflozin might differ by primary kidney disease across its broad population.

METHODS

EMPA-KIDNEY, a randomised, controlled, phase 3 trial, was conducted at 241 centres in eight countries (Canada, China, Germany, Italy, Japan, Malaysia, the UK, and the USA). Patients were eligible if their estimated glomerular filtration rate (eGFR) was 20 to less than 45 mL/min per 1·73 m2, or 45 to less than 90 mL/min per 1·73 m2 with a urinary albumin-to-creatinine ratio (uACR) of 200 mg/g or higher at screening. They were randomly assigned (1:1) to 10 mg oral empagliflozin once daily or matching placebo. Effects on kidney disease progression (defined as a sustained ≥40% eGFR decline from randomisation, end-stage kidney disease, a sustained eGFR below 10 mL/min per 1·73 m2, or death from kidney failure) were assessed using prespecified Cox models, and eGFR slope analyses used shared parameter models. Subgroup comparisons were performed by including relevant interaction terms in models. EMPA-KIDNEY is registered with ClinicalTrials.gov, NCT03594110.

FINDINGS

Between May 15, 2019, and April 16, 2021, 6609 participants were randomly assigned and followed up for a median of 2·0 years (IQR 1·5-2·4). Prespecified subgroupings by primary kidney disease included 2057 (31·1%) participants with diabetic kidney disease, 1669 (25·3%) with glomerular disease, 1445 (21·9%) with hypertensive or renovascular disease, and 1438 (21·8%) with other or unknown causes. Kidney disease progression occurred in 384 (11·6%) of 3304 patients in the empagliflozin group and 504 (15·2%) of 3305 patients in the placebo group (hazard ratio 0·71 [95% CI 0·62-0·81]), with no evidence that the relative effect size varied significantly by primary kidney disease (pheterogeneity=0·62). The between-group difference in chronic eGFR slopes (ie, from 2 months to final follow-up) was 1·37 mL/min per 1·73 m2 per year (95% CI 1·16-1·59), representing a 50% (42-58) reduction in the rate of chronic eGFR decline. This relative effect of empagliflozin on chronic eGFR slope was similar in analyses by different primary kidney diseases, including in explorations by type of glomerular disease and diabetes (p values for heterogeneity all >0·1).

INTERPRETATION

In a broad range of patients with chronic kidney disease at risk of progression, including a wide range of non-diabetic causes of chronic kidney disease, empagliflozin reduced risk of kidney disease progression. Relative effect sizes were broadly similar irrespective of the cause of primary kidney disease, suggesting that SGLT2 inhibitors should be part of a standard of care to minimise risk of kidney failure in chronic kidney disease.

FUNDING

Boehringer Ingelheim, Eli Lilly, and UK Medical Research Council.

A case of pancreatic adenosquamous carcinoma with direct invasion to the gastrointestinal tract through the retention cyst wall: A rare case report

A 62-year-old man presented with a 7-cm cystic lesion with irregularly thickened cyst wall in contact with the pancreatic tail. The pancreatic tail was described as hypoechoic on endoscopic ultrasonography. The cyst subsequently increased rapidly to 13 cm, and surgery was performed. This revealed adenosquamous carcinoma in the pancreatic tail to have invaded the stomach and transverse colon along the cyst wall. The cyst was diagnosed as a retention cyst due to pancreatic tail tumor. Invasion of nearby organs by a pancreatic cancer via the retention cyst wall is very rare, but it is necessary to keep the potential for such progress in mind.

Neurocognitive Function in Aged Survivors Exposed to Atomic Bomb Radiation In Utero: The Radiation Effects Research Foundation Adult Health Study

Although some adverse effects on neurocognitive function have been reported in children and adolescents irradiated prenatally during the atomic bombings and the Chernobyl nuclear accident, little information is available for effects on the elderly. Here we evaluate the effects of prenatal exposure to atomic bomb radiation on subjective neurocognitive function in aged survivors. To evaluate neurocognitive impairment, we mailed the Neurocognitive Questionnaire (NCQ), a self-administered scale, to prenatally exposed survivors, including clinic visitors and non-visitors at the time of the 2011 and 2013 Adult Health Study (AHS) examinations. We received replies from 444 individuals (mean age, 66.9 ± 0.6 years). After adjusting for sex, city, and educational background, we found no significant effects of radiation, clinic visit, or interaction between radiation and clinic visit on the scores of the 4 NCQ factors of metacognition, emotional regulation, motivation/organization, and processing speed. Even in analyses considering gestational age at the time of the bombings, none of the 4 NCQ factor scores was related to maternal uterine dose. There remains the limitation that this study consisted of healthy survivors, but we found no significant radiation effect on late-life cognition in people prenatally exposed to atomic bomb radiation.

Early-life atomic-bomb irradiation accelerates immunological aging and elevates immune-related intracellular reactive oxygen species

Reactive oxygen species (ROS) play an important role in immune responses; however, their excessive production and accumulation increases the risk of inflammation-related diseases. Although irradiation is known to accelerate immunological aging, the underlying mechanism is still unclear. To determine the possible involvement of ROS in this mechanism, we examined 10,023 samples obtained from 3752 atomic-bomb survivors in Hiroshima and Nagasaki, who participated in repeated biennial examinations from 2008 to 2016, for the effects of aging and radiation exposure on intracellular ROS (H2 O2 and O2 •- ) levels, percentages of T-cell subsets, and the effects of radiation exposure on the relationship between cell percentages and intracellular ROS levels in T-cell subsets. The cell percentages and intracellular ROS levels in T-cell subsets were measured using flow cytometry, with both fluorescently labeled antibodies and the fluorescent reagents, carboxy-DCFDA and hydroethidine. The percentages of naïve CD4+ and CD8+ T cells decreased with increasing age and radiation dose, while the intracellular O2 •- levels in central and effector memory CD8+ T cells increased. Additionally, when divided into three groups based on the percentages of naïve CD4+ T cells, intracellular O2 •- levels of central and effector memory CD8+ T cells were significantly elevated with the lowest radiation dose group in the naïve CD4+ T cells. Thus, the radiation exposure-induced decrease in the naïve CD4+ T cell pool size may reflect decreased immune function, resulting in increased intracellular ROS levels in central and effector memory CD8+ T cells, and increased intracellular oxidative stress.

Efficacy of a novel integrated biliary stent and nasobiliary catheter system for accidental tube deviation in biliary drainage

Background and study aims Endoscopic nasobiliary drainage is accompanied by a risk of accidental removal of the nasobiliary drainage (NBD) tube, especially through self-removal in elderly patients. We studied the usefulness of an integrated biliary stent and nasobiliary catheter system (UMIDAS NB stent) for biliary drainage in case of accidental NBD tube removal. Patients and methods From April to November 2022, we placed a UMIDAS NB stent in 30 patients with acute cholangitis or obstructive jaundice. We evaluated the plastic stent (PS) position at the time of accidental stent removal and before the planned endoscopic procedure. In addition, we studied the ratio of successful biliary drainage and complications based on the usage of UMIDAS. Results All 11 patients with accidental stent removal exhibited correct PS position in X-ray fluoroscopy. Of the 19 patients with planned NBD tube removal, three had complete PS migration into the common bile duct and three had incomplete migration (the duodenal side flap entered the bile duct). In summary, 80% (24/30) of PS were in the correct position, and all patients had successful biliary drainage and no complications. Conclusions The UMIDAS NB stent might be useful for biliary drainage in patients with a high risk of NBD tube self-removal.

First Dark Matter Search with Nuclear Recoils from the XENONnT Experiment

We report on the first search for nuclear recoils from dark matter in the form of weakly interacting massive particles (WIMPs) with the XENONnT experiment, which is based on a two-phase time projection chamber with a sensitive liquid xenon mass of 5.9 ton. During the (1.09±0.03)  ton yr exposure used for this search, the intrinsic ^{85}Kr and ^{222}Rn concentrations in the liquid target are reduced to unprecedentedly low levels, giving an electronic recoil background rate of (15.8±1.3)  events/ton yr keV in the region of interest. A blind analysis of nuclear recoil events with energies between 3.3 and 60.5 keV finds no significant excess. This leads to a minimum upper limit on the spin-independent WIMP-nucleon cross section of 2.58×10^{-47}  cm^{2} for a WIMP mass of 28  GeV/c^{2} at 90% confidence level. Limits for spin-dependent interactions are also provided. Both the limit and the sensitivity for the full range of WIMP masses analyzed here improve on previous results obtained with the XENON1T experiment for the same exposure.

Cells collectively migrate during ammonium chemotaxis in Chlamydomonas reinhardtii

The mechanisms governing chemotaxis in Chlamydomonas reinhardtii are largely unknown compared to those regulating phototaxis despite equal importance on the migratory response in the ciliated microalga. To study chemotaxis, we made a simple modification to a conventional Petri dish assay. Using the assay, a novel mechanism governing Chlamydomonas ammonium chemotaxis was revealed. First, we found that light exposure enhances the chemotactic response of wild-type Chlamydomonas strains, yet phototaxis-incompetent mutant strains, eye3-2 and ptx1, exhibit normal chemotaxis. This suggests that Chlamydomonas transduces the light signal pathway in chemotaxis differently from that in phototaxis. Second, we found that Chlamydomonas collectively migrate during chemotaxis but not phototaxis. Collective migration during chemotaxis is not clearly observed when the assay is conducted in the dark. Third, the Chlamydomonas strain CC-124 carrying agg1^-, the AGGREGATE1 gene (AGG1) null mutation, exhibited a more robust collective migratory response than strains carrying the wild-type AGG1 gene. The expression of a recombinant AGG1 protein in the CC-124 strain suppressed this collective migration during chemotaxis. Altogether, these findings suggest a unique mechanism; ammonium chemotaxis in Chlamydomonas is mainly driven by collective cell migration. Furthermore, it is proposed that collective migration is enhanced by light and suppressed by the AGG1 protein.

Searching for Heavy Dark Matter near the Planck Mass with XENON1T

Multiple viable theoretical models predict heavy dark matter particles with a mass close to the Planck mass, a range relatively unexplored by current experimental measurements. We use 219.4 days of data collected with the XENON1T experiment to conduct a blind search for signals from multiply interacting massive particles (MIMPs). Their unique track signature allows a targeted analysis with only 0.05 expected background events from muons. Following unblinding, we observe no signal candidate events. This Letter places strong constraints on spin-independent interactions of dark matter particles with a mass between 1×10^{12} and 2×10^{17}  GeV/c^{2}. In addition, we present the first exclusion limits on spin-dependent MIMP-neutron and MIMP-proton cross sections for dark matter particles with masses close to the Planck scale.

Clinical features and images of malignant lymphoma localized in the pancreatic head to differentiate from pancreatic ductal adenocarcinoma: a case series study

BACKGROUND

Pathological examination by endoscopic ultrasonography-guided fine-needle aspiration (EUS-FNA) has been reported to be useful in diagnosing pancreatic malignant lymphoma (ML), but some ML cases are difficult to be differentiated from pancreatic ductal adenocarcinoma (PDAC).

METHODS

This retrospective study included 8 patients diagnosed with ML that had a pancreatic-head lesion at initial diagnosis and 46 patients with resected PDAC in the pancreatic head between April 2006 and October 2021 at our institute. ML and PDAC were compared in terms of patients' clinical features and imaging examinations.

RESULTS

The median tumor size was larger in ML than in PDAC (45.8 [24-64] vs. 23.9 [8-44] mm), but the median diameter of the caudal main pancreatic duct (MPD) was larger in PDAC (2.5 [1.0-3.5] vs. 7.1 [2.5-11.8] mm), both showing significant differences between these malignancies (both, P < 0.001). In the analysis of covariance, MLs showed a smaller caudal MPD per tumor size than PDACs, with a statistical difference (P = 0.042). Sensitivity and specificity using sIL-2R ≥ 658 U/mL plus CA19-9 < 37 U/mL for the differentiation of ML from PDAC were 80.0% and 95.6%, respectively.

CONCLUSIONS

Diagnosing pancreatic ML using cytohistological examination through EUS-FNA can be difficult in some cases. Thus, ML should be suspected if a patient with a pancreatic tumor has a small MPD diameter per tumor size, high serum sIL-2R level, normal CA19-9 level. If the abovementioned features are present and still cannot be confirmed as PDAC, re-examination should be considered.

Spectra and characteristics of somatic mutations induced by ionizing radiation in hematopoietic stem cells

Spectra and frequencies of spontaneous and X-ray-induced somatic mutations were revealed with mouse long-term hematopoietic stem cells (LT-HSCs) by whole-genome sequencing of clonal cell populations propagated in vitro from single isolated LT-HSCs. SNVs and small indels were the most common types of somatic mutations, and increased up to twofold to threefold by whole-body X-irradiation. Base substitution patterns in the SNVs suggested a role of reactive oxygen species in radiation mutagenesis, and signature analysis of single base substitutions (SBS) revealed a dose-dependent increase of SBS40. Most of spontaneous small deletions were shrinkage of tandem repeats, and X-irradiation specifically induced small deletions out of tandem repeats (non-repeat deletions). Presence of microhomology sequences in non-repeat deletions suggested involvement of microhomology mediated end-joining repair mechanisms as well as nonhomologous end-joining in radiation-induced DNA damages. We also identified multisite mutations and structural variants (SV), i.e., large indels, inversions, reciprocal translocations, and complex variants. The radiation-specificity of each mutation type was evaluated from the spontaneous mutation rate and the per-Gy mutation rate estimated by linear regression, and was highest with non-repeat deletions without microhomology, followed by those with microhomology, SV except retroelement insertions, and multisite mutations; these types were thus revealed as mutational signatures of ionizing radiation. Further analysis of somatic mutations in multiple LT-HSCs indicated that large fractions of postirradiation LT-HSCs originated from single LT-HSCs that survived the irradiation and then expanded in vivo to confer marked clonality to the entire hematopoietic system, with varying clonal expansion and dynamics depending on radiation dose and fractionation.

Metastatic pancreatic ductal adenocarcinoma followed by a fatal diffuse large B-cell lymphoma: A rare case report and literature review

RATIONALE

Recently, the incidence of polyoncosis has been increasing due to advancements in treatment, such as antitumor therapy, which led to a prolonged survival. However, few patients with metastatic pancreatic ductal adenocarcinoma (PDAC) develop second tumors, which render a poor prognosis. We report a rare case of PDAC, which is metachronous with a fatal malignant lymphoma (ML).

PATIENT CONCERNS

A 68-year-old woman who had been monitored due to liver cirrhosis secondary to hepatitis C virus infection presented with a 10-mm pancreatic head cancer with lung metastasis and had started an anticancer therapy with gemcitabine. Approximately 18 months after diagnosis, lymphadenopathies around the pancreas were noted, which eventually spread to the entire body over time.

DIAGNOSIS

Diffuse large B-cell lymphoma was diagnosed using biopsies from cervical lymph nodes.

INTERVENTIONS AND OUTCOMES

The patient started a gemcitabine + rituximab regimen; however, the patient died from cachexia-associated lymphoma progression, not PDAC.

LESSONS

ML should be considered when intra-abdominal lymphadenopathies are detected in patients with pancreatic cancer, and ML should be differentiated from lymph node metastasis of pancreatic cancer.

Effectiveness of Abdominal Ultrasonography for Improving the Prognosis of Pancreatic Cancer during Medical Checkup: A Single Center Retrospective Analysis

Recent advancements in surgical and anti-cancer therapies have provided significant hope of long survival in patients with pancreatic cancer (PC). To realize this hope, routine medical checkups of asymptomatic people should be performed to identify operable PCs. In this study, we evaluated the efficacy of medical checkups using abdominal ultrasonography (US). We retrospectively analyzed 374 patients with PC at our institute between 2010 and 2021. We divided these patients into several groups according to the diagnostic approach and compared their background and prognosis. These groups comprised PCs diagnosed through (a) symptoms, 242 cases; (b) US during medical checkup for asymptomatic individuals, 17; and other means. Of the 374 patients, 192 were men (51.3%), and the median age was 74 years (34−105). Tumors were located in the pancreatic tail in 67 patients (17.9%). Excision ratio and 5-year survival rate were significantly better in group (b) than in (a) (58.8% vs. 23.1%, p < 0.01 and 42.2% vs. 9.4%, p < 0.001, respectively). The prognosis of patients diagnosed using US during medical checkup was better than that of patients identified through symptomatic presentation of PC. US for asymptomatic individuals with PC might be one of the useful modalities for promoting better prognosis of PCs.

Search for New Physics in Electronic Recoil Data from XENONnT

We report on a blinded analysis of low-energy electronic recoil data from the first science run of the XENONnT dark matter experiment. Novel subsystems and the increased 5.9 ton liquid xenon target reduced the background in the (1, 30) keV search region to (15.8±1.3)  events/(ton×year×keV), the lowest ever achieved in a dark matter detector and ∼5 times lower than in XENON1T. With an exposure of 1.16 ton-years, we observe no excess above background and set stringent new limits on solar axions, an enhanced neutrino magnetic moment, and bosonic dark matter.

Chlamydomonas reinhardtii Alternates Peroxisomal Contents in Response to Trophic Conditions

Chlamydomonas reinhardtii is a model green microalga capable of heterotrophic growth on acetic acid but not fatty acids, despite containing a full complement of genes for β-oxidation. Recent reports indicate that the alga preferentially sequesters, rather than breaks down, lipid acyl chains as a means to rebuild its membranes rapidly. Here, we assemble a list of potential Chlamydomonas peroxins (PEXs) required for peroxisomal biogenesis to suggest that C. reinhardtii has a complete set of peroxisome biogenesis factors. To determine involvements of the peroxisomes in the metabolism of exogenously added fatty acids, we examined transgenic C. reinhardtii expressing fluorescent proteins fused to N- or C-terminal peptide of peroxisomal proteins, concomitantly with fluorescently labeled palmitic acid under different trophic conditions. We used confocal microscopy to track the populations of the peroxisomes in illuminated and dark conditions, with and without acetic acid as a carbon source. In the cells, four major populations of compartments were identified, containing: (1) a glyoxylate cycle enzyme marker and a protein containing peroxisomal targeting signal 1 (PTS1) tripeptide but lacking the fatty acid marker, (2) the fatty acid marker alone, (3) the glyoxylate cycle enzyme marker alone, and (4) the PTS1 marker alone. Less than 5% of the compartments contained both fatty acid and peroxisomal markers. Statistical analysis on optically sectioned images found that C. reinhardtii simultaneously carries diverse populations of the peroxisomes in the cell and modulates peroxisomal contents based on light conditions. On the other hand, the ratio of the compartment containing both fatty acid and peroxisomal markers did not change significantly regardless of the culture conditions. The result indicates that β-oxidation may be only a minor occurrence in the peroxisomal population in C. reinhardtii, which supports the idea that lipid biosynthesis and not β-oxidation is the primary metabolic preference of fatty acids in the alga.

Dynamic modeling of ABA-dependent expression of the Arabidopsis RD29A gene

The abscisic acid (ABA) signaling pathway is the key defense mechanism against drought stress in plants. In the pathway, signal transduction among four core proteins, pyrabactin resistance (PYR), protein phosphatase 2C (PP2C), sucrose-non-fermenting-1-related protein kinase 2 (SnRK2), and ABRE binding factor (ABF) leads to altered gene expression kinetics that is driven by an ABA-responsive element (ABRE). A most recent and comprehensive study provided data suggesting that ABA alters the expression kinetics in over 6,500 genes through the ABF-ABRE associations in Arabidopsis. Of these genes, termed ABA gene regulatory network (GRN), over 50% contain a single ABRE within 4 kb of the gene body, despite previous findings suggesting that a single copy of ABRE is not sufficient to drive the gene expression. To understand the expression system of the ABA GRN by the single ABRE, a dynamic model of the gene expression for the desiccation 29A (RD29A) gene was constructed with ordinary differential equations. Parameter values of molecular-molecular interactions and enzymatic reactions in the model were implemented from the data obtained by previously conducted in vitro experiments. On the other hand, parameter values of gene expression and translation were determined by comparing the kinetics of gene expression in the model to the expression kinetics of RD29A in real plants. The optimized model recapitulated the trend of gene expression kinetics of RD29A in ABA dose-response that were previously investigated. Further analysis of the model suggested that a single ABRE controls the time scale and dynamic range of the ABA-dependent gene expression through the PP2C feedback regulation even though an additional cis-element is required to drive the expression. The model construed in this study underpins the importance of a single ABRE in the ABA GRN.

Material radiopurity control in the XENONnT experiment

The selection of low-radioactive construction materials is of the utmost importance for rare-event searches and thus critical to the XENONnT experiment. Results of an extensive radioassay program are reported, in which material samples have been screened with gamma-ray spectroscopy, mass spectrometry, and \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$^{222}$$\end{document}222Rn emanation measurements. Furthermore, the cleanliness procedures applied to remove or mitigate surface contamination of detector materials are described. Screening results, used as inputs for a XENONnT Monte Carlo simulation, predict a reduction of materials background (\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$\sim $$\end{document}∼17%) with respect to its predecessor XENON1T. Through radon emanation measurements, the expected \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$^{222}$$\end{document}222Rn activity concentration in XENONnT is determined to be 4.2 (\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$^{+0.5}_{-0.7}$$\end{document}-0.7+0.5) \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$\upmu $$\end{document}μBq/kg, a factor three lower with respect to XENON1T. This radon concentration will be further suppressed by means of the novel radon distillation system.

Radiation Effects on Late-life Neurocognitive Function in Childhood Atomic Bomb Survivors: A Radiation Effects Research Foundation Adult Health Study

High-dose radiation in childhood such as is used in radiation therapy causes cognitive decline, but there is insufficient research on the cognitive effects of low- to medium-dose radiation. We aimed to reveal the association between atomic bomb radiation exposure in childhood and late-life neurocognitive function. In 2011 and 2013, we mailed the Neurocognitive Questionnaire (NCQ) to subjects who were 12 years old or younger at the time of the atomic bombing. We converted the four NCQ subscales (metacognition, emotional regulation, motivation/organization, and processing speed) to T scores and defined the highest 10% of the controls (exposure dose < 5 mGy) as impaired. We used a generalized linear mixed model to evaluate the effect of radiation exposure on T scores and percentage impaired. We enrolled 859 participants. At the time of the bombing, the mean (SD) age was 6.7 (3.8) years for the control (N = 390) and 6.1 (3.8) years for the exposed (N = 469). At the time of replying to the questionnaire, the mean age of all the participants was 73.7 (3.8) years of age. After adjusting for cofactors, older age was related to the decline of all neurocognitive subscales. Sex and education level had relevance to some of the subscales. For neurocognitive function, exposure dose was not related except to percentage impaired, motivation/organization. Late-life neurocognitive function in atomic bomb survivors exposed as children was associated with age, but not clearly with radiation dose. More studies are needed to evaluate the effect of low-dose radiation during childhood on long-term neurocognitive function.

Evidence for thermosensitivity of the cotton (Gossypium hirsutum L.) immature fiber (im) mutant via hypersensitive stomatal activity

Thickness of cotton fiber, referred to as fiber maturity, is a key determinant of fiber quality, lint yield, and textile performance. The cotton immature fiber (im) mutant has been used to study fiber maturity since its fiber is thinner than the wild type near isogeneic line (NIL), Texas Marker-1 (TM-1). The im phenotype is caused by a single recessive mutation of a pentatricopeptide repeat (PPR) gene that reduces the activity of mitochondrial complex I and up-regulates stress responsive genes. However, the mechanisms altering the stress responses in im mutant are not well understood. Thus, we characterized growth and gas exchange in im and TM-1 under no stress and also investigated their stress responses by comparing gas exchange and transcriptomic profiles under high temperature. Phenotypic differences were detected between the NILs in non-fiber tissues although less pronounced than the variation in fibers. At near optimum temperature (28±3°C), im maintained the same photosynthetic performance as TM-1 by means of greater stomatal conductance. In contrast, under high temperature stress (>34°C), im leaves reduced photosynthesis by decreasing the stomatal conductance disproportionately more than TM-1. Transcriptomic analyses showed that the genes involved in heat stress responses were differentially expressed between the NIL leaves. These results indicate that the im mutant previously reported to have low activity of mitochondrial complex I displays increased thermosensitivity by impacting stomatal conductance. They also support a notion that mitochondrial complex I activity is required for maintenance of optimal photosynthetic performance and acclimation of plants to high temperature stress. These findings may be useful in the future efforts to understand how physiological mechanisms play a role in determining cotton fiber maturity and may influence stress responses in other crops.

Intracellular reactive oxygen species level in blood cells of atomic bomb survivors is increased due to aging and radiation exposure

Although reactive oxygen species (ROS) play important roles in immune responses, excessive ROS production and accumulation might enhance the risk of inflammation-related diseases. Moreover, impaired immune function and the acceleration of pre-clinically persistent inflammation due to aging and radiation exposure have been observed in atomic bomb (A-bomb) survivors more than 60 years post-exposure. Meanwhile, the effects of aging and radiation exposure on ROS production in immune cells have not been characterized. This study investigated the relationship between intracellular ROS (H₂O₂ and O₂^•-) levels in blood cells or T cell subsets and serum iron, ferritin, and C-reactive protein (CRP) levels, as well as how these variables are affected by age and radiation exposure in A-bomb survivors. We examined 2495 Hiroshima A-bomb survivors. Multiple linear regression models adjusted for confounding factors indicated that intracellular O₂^•- levels in monocytes, granulocytes, and lymphocytes, and particularly in memory CD8⁺ T cells, including effector memory and terminally differentiated effector memory CD8⁺ T cells, increased with radiation dose. Additionally, serum iron, ferritin, and CRP levels affected intracellular ROS levels in specific blood cell types and T cell subsets. Serum CRP levels increased significantly with increasing age and radiation dose. Finally, when divided into three groups according to serum CRP levels, dose-dependent increases in the intracellular O₂^•- levels in blood cells and central memory and effector memory CD8⁺ T cells were most prominently observed in the high-CRP group. These results suggest that an increase in the levels of certain intracellular ROS, particularly after radiation exposure, might be linked to enhanced inflammatory status, including elevated serum CRP levels and reduced serum iron levels. This study reveals that aging and radiation exposure increase oxidative stress in blood cells, which is involved in impaired immune function and accelerated pre-clinically persistent inflammation in radiation-exposed individuals.

Validation of the World Health Organization/ International Society of Hypertension (WHO/ISH) cardiovascular risk predictions in Sri Lankans based on findings from a prospective cohort study

Introduction and objectives

There are no cardiovascular (CV) risk prediction models for Sri Lankans. Different risk prediction models not validated for Sri Lankans are being used to predict CV risk of Sri Lankans. We validated the WHO/ISH (SEAR-B) risk prediction charts prospectively in a population-based cohort of Sri Lankans.

Method

We selected 40–64 year-old participants from the Ragama Medical Officer of Health (MOH) area in 2007 by stratified random sampling and followed them up for 10 years. Ten-year risk predictions of a fatal/non-fatal cardiovascular event (CVE) in 2007 were calculated using WHO/ISH (SEAR-B) charts with and without cholesterol. The CVEs that occurred from 2007–2017 were ascertained. Risk predictions in 2007 were validated against observed CVEs in 2017.

Results

Of 2517 participants, the mean age was 53.7 year (SD: 6.7) and 1132 (45%) were males. Using WHO/ISH chart with cholesterol, the percentages of subjects with a 10-year CV risk <10%, 10–19%, 20%-29%, 30–39%, ≥40% were 80.7%, 9.9%, 3.8%, 2.5% and 3.1%, respectively. 142 non-fatal and 73 fatal CVEs were observed during follow-up. Among the cohort, 9.4% were predicted of having a CV risk ≥20% and 8.6% CVEs were observed in the risk category. CVEs were within the predictions of WHO/ISH charts with and without cholesterol in both high (≥20%) and low(<20%) risk males, but only in low(<20%) risk females. The predictions of WHO/ISH charts, with-and without-cholesterol were in agreement in 81% of subjects (ĸ = 0.429; p<0.001).

Conclusions

WHO/ISH (SEAR B) risk prediction charts with-and without-cholesterol may be used in Sri Lanka. Risk charts are more predictive in males than in females and for lower-risk categories. The predictions when stratifying into 2 categories, low risk (<20%) and high risk (≥20%), are more appropriate in clinical practice.

Auditory brainstem responses in adults with autism spectrum disorder

OBJECTIVE

To investigate possible differences in the auditory peripheral and brainstem functions between adults with autism spectrum disorder (ASD) and neurotypical (NT) adults.

METHODS

Click-evoked auditory brainstem responses (ABRs) were obtained from 17 high-functioning ASD adults (aged 21-38 years) and 20 NT adults (aged 22-36 years). A relatively large number of stimulus presentations (6000) were adopted, and ABRs by horizontal and vertical electrode montages were evaluated, in order to allow precise evaluations of early ABR components.

RESULTS

Waves I, II, III, and V were identified in the vertical electrode montage, and wave I and the summating potential (SP) in electrocochleograms were identified in the horizontal electrode montage. There were no significant group differences in the wave I, II, III, and V latencies or the interpeak latencies (IPLs) in the vertical electrode montage. In the horizontal montage, the ASD adults exhibited significantly shortened SP latencies compared with the NT adults, whereas there was no significant group difference in the wave I latency.

CONCLUSION

The ASD adults may have the abnormalities of processing more in the peripheral auditory system than in the brainstem.

SIGNIFICANCE

The current study suggests that the peripheral abnormality is associated with ASD.

Radiation Risk of Ovarian Cancer in Atomic Bomb Survivors: 1958-2009

There is limited evidence concerning the association between radiation exposure and ovarian cancer. We evaluated radiation risk of ovarian cancer between 1958 and 2009 among 62,534 female atomic bomb survivors in the Life Span Study cohort, adding 11 years of follow-up from the previously reported study. Poisson regression methods were used to estimate excess relative risk per Gy (ERR/Gy) for total ovarian cancer and according to tumor type. We assessed the modifying effect of follow-up period and other factors on the radiation risk. We ascertained 288 first primary ovarian cancers including 77 type 1 epithelial cancers, 75 type 2 epithelial cancers, 66 epithelial cancers of undetermined type and 70 other cancers. Radiation dose was positively, although not significantly, associated with risk of total ovarian cancer [ERR/Gy = 0.30, 95% confidence interval (CI): -0.22 to 1.11]. There was a suggestion of heterogeneity in radiation effects (P = 0.08) for type 1 (ERR/Gy = -0.32, 95% CI: <-0.32 to 0.88) and type 2 cancers (ERR/Gy = 1.24, 95% CI: -0.08 to 4.16). There were no significant trends in the ERR with time since exposure or age at exposure. Further follow-up will help characterize more accurately the patterns of radiation risk for total ovarian cancer and its types.

222 Rn emanation measurements for the XENON1T experiment

The selection of low-radioactive construction materials is of utmost importance for the success of low-energy rare event search experiments. Besides radioactive contaminants in the bulk, the emanation of radioactive radon atoms from material surfaces attains increasing relevance in the effort to further reduce the background of such experiments. In this work, we present the 222 Rn emanation measurements performed for the XENON1T dark matter experiment. Together with the bulk impurity screening campaign, the results enabled us to select the radio-purest construction materials, targeting a 222 Rn activity concentration of 10 μ Bq / kg in 3.2 t of xenon. The knowledge of the distribution of the 222 Rn sources allowed us to selectively eliminate problematic components in the course of the experiment. The predictions from the emanation measurements were compared to data of the 222 Rn activity concentration in XENON1T. The final 222 Rn activity concentration of ( 4.5 ± 0.1 ) μ Bq / kg in the target of XENON1T is the lowest ever achieved in a xenon dark matter experiment.

Cognitive Function Among Elderly Survivors Prenatally Exposed to Atomic Bombings

BACKGROUND

A cohort of children prenatally exposed to the 1945 atomic bombings in Japan revealed harmful effects of ionizing radiation in a variety of measures of cognitive function, including mental retardation. Here we examined cognitive function in the non-affected, now elderly, cohort.

METHODS

From 2011-2015, using the Cognitive Abilities Screening Instrument and a maternal uterine radiation dose estimated with the 2002 dosimetry system, we evaluated 303 prenatally exposed subjects and their non-exposed controls from the Adult Health Study of the Radiation Effects Research Foundation, excluding those who had shown marked cognitive effects earlier. About 11% of the subjects were exposed to more than 250 mGy. We examined a self-reported disease history and, using regression analysis, evaluated the relationship between cognitive function and radiation exposures, adjusting for demographic factors.

RESULTS

None of the subjects reported a history of dementia. We also did not find a significant radiation effect on cognitive function overall or in any gestational-week group. Education was associated with a significant effect, but educational level was not associated with radiation dose.

CONCLUSION

We found no significant radiation effect on cognitive function among 65- to 70-year-old subjects who were prenatally exposed to the bombings and did not have marked childhood cognitive function deterioration. The limitations of this study include a small sample size and potential bias pertaining to non-participation in the Adult Health Study or refusal of Cognitive Abilities Screening Instrument evaluation. Further investigations using various endpoints in other populations prenatally exposed to radiation are warranted.

Search for Coherent Elastic Scattering of Solar ^{8}B Neutrinos in the XENON1T Dark Matter Experiment

We report on a search for nuclear recoil signals from solar ^{8}B neutrinos elastically scattering off xenon nuclei in XENON1T data, lowering the energy threshold from 2.6 to 1.6  keV. We develop a variety of novel techniques to limit the resulting increase in backgrounds near the threshold. No significant ^{8}B neutrinolike excess is found in an exposure of 0.6  t×y. For the first time, we use the nondetection of solar neutrinos to constrain the light yield from 1-2 keV nuclear recoils in liquid xenon, as well as nonstandard neutrino-quark interactions. Finally, we improve upon world-leading constraints on dark matter-nucleus interactions for dark matter masses between 3 and 11  GeV c^{-2} by as much as an order of magnitude.

Comprehensive study of the light-off performance and surface properties of engine-aged Pd-based three-way catalysts

Pd particles with a high fraction of corner sites on low-index facets are highly active for three-way catalyst reactions.

A novel mitral stenosis assessment using projected transmitral gradient improves the diagnostic and prognostic yields of doppler-based gradient

Background

Transmitral gradient (TMG) is highly dependent on hemodynamic state, leading to discordance between TMG and mitral valve area (MVA). The effect of heart rate (HR) and stroke volume (SV) on TMG among patients with mitral stenosis (MS) is poorly understood.

Purposes

We aimed to (1) develop a formula for projected TMG (proTMG) for assessment of MS severity under varying hemodynamics; (2) assess the prognostic value of proTMG in patients with MS.

Methods

All patients evaluated for suspected MS without ≥moderate other valve disorder at our tertiary center between 2001 and 2017 were analyzed. Projected TMG is the expected gradient under normal flow (SV 80–94 ml and HR 60–79 bpm), and was modeled based on the observed impact of HR and SV on TMG by multiple regression analysis. The data were randomly split (2:1) into training and testing sets. The improvement in agreement between MVA and proTMG was evaluated. Composite cardiac events including all-cause death and mitral valve interventions were compared according to TMG grade using TMG and proTMG. Severe and moderate MS were defined as MVA ≤1.5 cm2 and 1.5–2.0 cm2 respectively, by the continuity equation. MVA ≤1.0 cm2 was considered as very severe MS.

Results

Of 4973 patients with suspected MS (age 73±12 years, 33% male), severe MS was present in 437 (9%, including 98 with very severe MS) and moderate MS in 934 (19%). In 838 patients with normal HR and SV, very severe, severe and moderate MS corresponded to TMG ≥12 mmHg, ≥6 mmHg and 4–6 mmHg, respectively. In the training set (n=3315), the median [interquartile range] of HR and SV were 70 [61–80] bpm and 97 [83–113] mL in men (n=1120), and 72 [63–82] bpm and 84 [71–97] mL in women (n=2195), respectively. The impact of HR and SV on TMG for men and women were 0.07 and 0.08 mmHg per 1 bpm increase in HR (95% confidence interval [CI] 0.06–0.07 and 0.07–0.08), and 0.03 and 0.05 mmHg per 1 mL increase in SV (95% CI 0.03–0.03 and 0.04–0.05), respectively. Therefore, the final formula to calculate proTMG was: proTMG=TMG-0.07(HR-70)-0.03(SV-97) in men and proTMG=TMG-0.08(HR-72)-0.05(SV-84) in women. In the testing set (n=1658), the proTMG (kappa=0.63, 95% CI 0.60–0.66) had better agreement with MS severity by MVA than TMG (kappa=0.28, 95% CI 0.24–0.32). To explore the prevalence of patients reclassified using proTMG, in 98 with TMG ≥12 mmHg, proTMG remained ≥6 mmHg. Of 657 with TMG 6–12 mmHg, proTMG remained ≥6 mmHg in 356 (54%), and decreased to &lt;6 mmHg in 301 (46%). In patients with TMG 6–12 mmHg, proTMG ≥6 mmHg was associated with higher probability of cardiac events compared with &lt;6 mmHg during follow-up of 2.8±3.1 years (Figure).

Conclusion

We propose a novel concept of projected TMG defined as the expected transmitral gradient at normal HR and SV levels. This improved the diagnostic yield of Doppler TMG measurements for MS severity assessment and identified a low-risk subset of patients with elevated TMG due to high HR or SV.

Funding Acknowledgement

Type of funding source: None

The prevalence and natural history of mitral annulus calcification

Background

There is a paucity of data about the prevalence and natural history of mitral annular calcification (MAC).

Purposes

In a large cohort of patients undergoing clinically-indicated echocardiography, we aimed to evaluate the prevalence and the natural history of MAC, and the frequency of associated mitral valve dysfunction (MVD).

Methods

Retrospective review of all patients who underwent echocardiographic evaluation at our institution between January 1st and December 31st 2015. The patients were stratified into 3 groups: MAC with MVD, MAC without MVD, no MAC. MVD was defined as moderate or greater mitral regurgitation (MR) or stenosis (MS). The 3 groups were compared for baseline clinical and echocardiographic characteristics and all-cause mortality during follow-up.

Results

Of 24,415 evaluated patients, 5478 (22%) had MAC. Patients with MAC were older (75±10 vs. 60±16 years, p&lt;0.01) and more often female (46% vs. 43%, p&lt;0.01). MVD was more frequently observed in patients with MAC (16% vs. 7%, p&lt;0.01); moderate or greater MR was found in 10% of patients with MAC vs. 6% without MAC (p&lt;0.01) and MS in 7% vs. 0.5% (p&lt;0.01). In patients with MAC, those with MVD were more often female and more frequently had creatinine ≥2mg/dl and moderate or greater aortic stenosis (AS) than those without MVD (Fig. A). Kaplan-Meier survivals at 1 year were 75% in patients with MAC and MVD, 87% in those with MAC without MVD, and 92% in those without MAC (Fig B). Adjusted for age, sex, diabetes, creatinine ≥2 mg/dl, coronary artery disease, left ventricular ejection fraction &lt;50%, and AS, MAC was associated with higher all-cause mortality (adjusted hazard ratio1.4, 95% confidence interval: 1.3–1.5, p&lt;0.01); combined MAC and MVD was associated with the highest mortality during follow-up of 2.5±1.8 years.

Conclusion

In a large cohort of patients undergoing echocardiographic evaluation, the prevalence of MAC was 22%. MV dysfunction was more than twice as prevalent in patients with MAC as without. Patients with MAC had higher all-cause mortality than patients without MAC. Among patients with MAC and mitral valvular dysfunction, adjusted mortality was two-fold higher compared to those without MAC.

Funding Acknowledgement

Type of funding source: None

Symptoms and natural history in patients with isolated severe calcific mitral stenosis

Background

Prevalence of calcific mitral stenosis (MS) increases with age. Mitral valve interventions for calcific MS are often delayed until symptoms are severely limiting because the natural history of calcific MS and its relation to cardiac symptoms or comorbidities have not been well assessed.

Objectives

We assessed the prevalence of symptoms, comorbidities and determinants of all-cause mortality in patients with severe calcific MS.

Methods

We retrospectively investigated adults with echocardiographic isolated severe MS, defined as mitral valve area (MVA by the continuity equation) ≤1.5 cm2, from July 2003 to December 2017. Among them, calcific MS was identified as obstruction of left ventricular inflow due to degenerative calcification of the mitral annulus using echocardiography and, whenever available, operative findings including histopathological examination. Inactivity was defined as requirement for assistance with activities of daily living. Follow up was obtained by review of medical records.

Results

Of 491 patients with isolated severe MS, calcific MS was present in 200 (41%; age 78±11 years, 18% men, 32% with atrial fibrillation). Charlson Comorbidity Index (CCI) was 5.1±1.7 and 14 (7%) were inactive. MVA and transmitral gradient (TMG) were 1.26±0.19 cm2 and 8.1±3.8 mmHg, respectively. Symptoms were present at baseline in 120 (60%) including dyspnea in 97, chest discomfort in 12, syncope in 3, lower extremity edema in 3, thrombosis in 3 and fatigue in 2. Of them, mitral valve interventions including surgical or transcatheter mitral valve replacement and mitral valve bypass were performed in 27 (23%): within 1 year after index TTE in 23 (19%) and at 2, 4, 5 and 6 years in 1 each. Of 80 patients without symptoms at index TTE, 20 (25%) developed symptoms at mean 2.9±3.2 years and interventions were performed in 5 (6%). Of 168 who did not receive interventions, 60 (36%) did not develop symptoms during follow up, 58 (35%) were considered to have moderate MS, 46 (27%) were not offered surgery because of high risk due to advanced age, multiple comorbidities or heavy calcification, and 2 (1%) declined interventions. During follow-up of 2.8±3.0 years, Kaplan-Meier survival at 1 and 3 years without intervention were 72% and 52%, respectively (Fig. A). Inactivity, CCI &gt;5, left ventricular ejection fraction (LVEF) &lt;50%, TMG ≥8 mmHg (the mean TMG) and right ventricular systolic pressure (RVSP) ≥50 mmHg were independently associated with mortality (Fig. B). Symptoms were associated with referral for interventions (OR 3.43, 95% CI 1.22–9.65; p=0.019), but not with mortality.

Conclusion

Patients with isolated severe calcific MS had a high burden of comorbidities and had high mortality without intervention. Symptoms were common (60%), but were not associated with mortality. TMG ≥8 mmHg, RVSP ≥50 mmHg, LVEF&lt;50%, CCI &gt;5 and inactivity were independently associated with mortality.

Funding Acknowledgement

Type of funding source: None

Development and validation of risk models for mortality and morbidity in 12 major pediatric surgical procedures: A study from the National Clinical Database-Pediatric of Japan

PURPOSE

To establish and validate risk models of mortality and morbidity associated with 12 major pediatric surgical procedures using the National Clinical Database-Pediatric (NCD-P) data.

METHODS

We used the NCD-P data for the development and validation datasets. By using multivariate logistic regression to analyze the development dataset, we created a prediction model for 30-day mortality and morbidity in 12 major pediatric surgical procedures, including tracheoplasty, pneumonectomy, fundoplication, total/subtotal excision of malignant tumor, and surgeries for Hirschsprung disease, anorectal malformation, biliary atresia, choledocal cyst, midgut volvulus, funnel chest, gastrointestinal perforation, and intestinal obstruction. We selected variables that were almost identical to those used in the American College of Surgeons National Surgical Quality Improvement Program-Pediatric (NSQIP-P). The primary outcomes were 30-day mortality and composite morbidity. We assessed the obtained models using the C-indices of the development and validation datasets.

RESULTS

Overall, 10 and 21 variables were identified for mortality and morbidity, respectively. C-indices of mortality were 0.940 and 0.924 in the development and validation datasets, respectively. C-indices of morbidity were 0.832 and 0.830 in the development and validation datasets, respectively.

CONCLUSIONS

Based on the NCD-P data, we developed satisfactory risk models for mortality and morbidity prediction in major pediatric surgeries.

LEVEL OF EVIDENCE

Level I (Prognosis Study).

Development of Bayesian Mortality Categories for Congenital Cardiac Surgery in Japan

BACKGROUND

Surgery requires a complexity-based ranking system that provides critical information for surgeons to perform strategic operations. However, we still use professional panel systems such as the Risk Adjustment for Congenital Heart Surgery category and the Aristotle Basic Complexity score for this purpose, both of which are subjective. The present study, inspired by more recent development of The Society of Thoracic Surgeons-European Association for Cardiothoracic Surgery mortality scores and categories, applied a Bayesian statistical method to the Japanese nationwide congenital heart registry by estimating inhospital mortality to construct a data-driven, more scientific rating system based on complexity.

METHODS

The study used a 5-year dataset from the Japan Cardiovascular Surgery Database congenital section to construct a Bayesian estimation model. There were 25,968 operations with 186 cardiovascular procedures. To validate the model, we used an independent 2-year dataset with 14,904 operations.

RESULTS

The model-based inhospital mortality estimation provided a complexity rating system that replicated the past study that had proposed a five-category system based on the estimated mortality scores. The C-index with the validation dataset for the mortality score and category was 0.80 and 0.79, respectively.

CONCLUSIONS

The data-driven approach to complexity rating systems for congenital cardiovascular surgery is recommended, as it has better scientific advantages and more convenient updating features.

The CDK Inhibitor SIAMESE Targets Both CDKA;1 and CDKB1 Complexes to Establish Endoreplication in Trichomes

Endoreplication, also known as endoreduplication, is a modified cell cycle in which DNA is replicated without subsequent cell division. Endoreplication plays important roles in both normal plant development and in stress responses. The SIAMESE (SIM) gene of Arabidopsis (Arabidopsis thaliana) encodes a cyclin-dependent kinase (CDK) inhibitor that plays a central role in establishing endoreplication, and is the founding member of the SIAMESE-RELATED (SMR) family of plant-specific CDK inhibitor genes. However, there has been conflicting evidence regarding which specific cyclin/CDK complexes are inhibited by SIM in vivo. In this work, we use genetic evidence to show that SIM likely inhibits both CDKA;1- and CDKB1-containing CDK complexes in vivo, thus promoting endoreplication in developing Arabidopsis trichomes. We also show that SIM interacts with CYCA2;3, a binding partner of CDKB1;1, via SIM motif A, which we previously identified as a CDK-binding motif. By contrast, SIM motif C, which has been indicated as a cyclin binding motif in other contexts, appears to be relatively unimportant for interaction between SIM and CYCA2;3. Together with earlier results, our work suggests that SIM and other SMRs likely have a multivalent interaction with CYC/CDK complexes.

Delayed Leukoencephalopathy: A Rare Complication after Coiling of Cerebral Aneurysms

BACKGROUND AND PURPOSE

Delayed leukoencephalopathy is a rare complication that occurs after endovascular coiling of cerebral aneurysms. We aimed to describe a clinical picture of delayed leukoencephalopathy and explore potential associations with procedural characteristics.

MATERIALS AND METHODS

We considered endovascular coiling procedures for cerebral aneurysms performed between January 2006 and December 2017 in our institution with follow-up MRIs. We used logistic regression models to estimate the ORs of delayed leukoencephalopathy for each procedural characteristic.

RESULTS

We reviewed 1754 endovascular coiling procedures of 1594 aneurysms. Sixteen of 1722 (0.9%) procedures demonstrated delayed leukoencephalopathy on follow-up FLAIR MR imaging examinations after a median period of 71.5 days (interquartile range, 30-101 days) in the form of high-signal changes in the white matter at locations remote from the coil mass. Seven patients had headaches or hemiparesis, and 9 patients were asymptomatic. All imaging-associated changes improved subsequently. We found indications suggesting an association between delayed leukoencephalopathy and the number of microcatheters used per procedure (P = .009), along with indications suggesting that these procedures required larger median volumes of contrast medium (225 versus 175 mL, OR = 5.5, P = .008) as well as a longer median fluoroscopy duration (123.6 versus 99.3 minutes, OR = 3.0, P = .06). Our data did not suggest that delayed leukoencephalopathy was associated with the number of coils (P = .57), microguidewires (P = .35), and guiding systems (P = .57).

CONCLUSIONS

Delayed leukoencephalopathy after coiling of cerebral aneurysms may have multiple etiologies such as foreign body emboli, contrast-induced encephalopathy, or hypersensitivity reaction to foreign bodies.

Combination gemcitabine plus S-1 versus gemcitabine plus cisplatin for advanced/recurrent biliary tract cancer: the FUGA-BT (JCOG1113) randomized phase III clinical trial

BACKGROUND

Gemcitabine plus cisplatin (GC) is the standard treatment of advanced biliary tract cancer (BTC); however, it causes nausea, vomiting, and anorexia, and requires hydration. Gemcitabine plus S-1 (GS) reportedly has equal to, or better, efficacy and an acceptable toxicity profile. We aimed to confirm the non-inferiority of GS to GC for patients with advanced/recurrent BTC in terms of overall survival (OS).

PATIENTS AND METHODS

We undertook a phase III randomized trial in 33 institutions in Japan. Eligibility criteria included chemotherapy-naïve patients with recurrent or unresectable BTC, an Eastern Cooperative Oncology Group Performance Status of 0 - 1, and adequate organ function. The calculated sample size was 350 with a one-sided α of 5%, a power of 80%, and non-inferiority margin hazard ratio (HR) of 1.155. The primary end point was OS, while the secondary end points included progression-free survival (PFS), response rate (RR), adverse events (AEs), and clinically significant AEs defined as grade ≥2 fatigue, anorexia, nausea, vomiting, oral mucositis, or diarrhea.

RESULTS

Between May 2013 and March 2016, 354 patients were enrolled. GS was found to be non-inferior to GC [median OS: 13.4 months with GC and 15.1 months with GS, HR, 0.945; 90% confidence interval (CI), 0.78-1.15; P = 0.046 for non-inferiority]. The median PFS was 5.8 months with GC and 6.8 months with GS (HR 0.86; 95% CI 0.70-1.07). The RR was 32.4% with GC and 29.8% with GS. Both treatments were generally well-tolerated. Clinically significant AEs were observed in 35.1% of patients in the GC arm and 29.9% in the GS arm.

CONCLUSIONS

GS, which does not require hydration, should be considered a new, convenient standard of care option for patients with advanced/recurrent BTC.

CLINICAL TRIAL NUMBER

This trial has been registered with the UMIN Clinical Trials Registry (http://www.umin.ac.jp/ctr/index.htm), number UMIN000010667.

P1786Impact of surgery for mitral regurgitation at the time of aortic valve replacement

Background

Functional mitral regurgitation (MR) is expected to improve after aortic valve replacement (AVR) in patients with severe aortic stenosis (sAS) and MR. However, little is unknown about the impact of AVR on organic MR and whether concomitant mitral valve surgery (MVS) improves outcomes in patients with sAS and MR.

Purpose

We assessed the impact of AVR on MR severity according to MR mechanism. We also assessed the clinical outcomes in patients with sAS and MR that underwent AVR with vs without MVS.

Methods

We retrospectively investigated patients who received surgical AVR or transcatheter aortic valve implantation (TAVI) from 2008 to 2017. We identified patients with effective mitral regurgitant orifice area (ERO) ≥10 mm2 by the proximal isovelocity surface area method with transthoracic echocardiography. The change in MR after AVR was considered significant when there was at least one grade difference. We compared the all-cause mortality of patients with sAS and MR that underwent AVR with vs without MVS according to MR mechanism and patient age.

Results

We included 326 patients with sAS and MR (age 80 [Interquartile range 72–85] years, 53% male, 21% history of myocardial infarction). Organic and functional MR were present in 69% and 31%, respectively. Of these, 240 underwent AVR alone (AVR group) including TAVI in 112 while 86 underwent AVR and MVS (MVS group) including mitral valve replacement in 38 and mitral valve repair in 48. The median ERO at baseline was 17 (14–21) mm2 in AVR and 24 (19–33) mm2 in MVS (p<0.001). Improvement in MR was observed in 58% of AVR and 91% of MVS (p<0.001). In AVR group, organic MR improved as frequently as functional MR (58% vs. 59%, p=0.96). Predictors for improvement in organic MR were absence of atrial fibrillation and moderate or greater MR, and in functional MR, the only predictor was decrease in LV end-systolic diameter after AVR. During mean follow-up of 2.4±2.3 years, moderate or greater MR was observed in 23% of AVR and 7% of MVS (p=0.002). All-cause mortality was similar in AVR and MVS groups for organic and functional MR (hazard ratio for MVS group 0.68, 95% CI: 0.40–1.10, p=0.13 in organic MR and 0.62, 95% CI 0.29–1.22, p=0.68 in functional MR). All-cause mortality was lower in MVS group compared with AVR group in patients <80 years, and was similar in patients ≥80 years (Figure).

Conclusion

In patients with sAS and MR, MR improves after AVR, even in the majority of patients with organic MR. Compared with isolated AVR, concomitant MVS was associated with better prognosis in patients <80 years.

Non-Steady State Analysis of Enzyme Kinetics in Real Time Elucidates Substrate Association and Dissociation Rates: Demonstration with Analysis of Firefly Luciferase Mutants

Firefly luciferase has been widely used in biotechnology and biophotonics due to photon emission during enzymatic activity. In the past, the effect of amino acid substitutions (mutants) on the enzymatic activity of firefly luciferase has been characterized by the Michaelis constant, KM. The KM is obtained by plotting the maximum relative luminescence units (RLU) detected for several concentrations of the substrate (luciferin or luciferyl-adenylate). The maximum RLU is used because the assay begins to violate the quasi-steady state approximation when RLU decays as a function of time. However, mutations also affect the time to reach and decay from the maximum RLU. These effects are not captured when calculating the KM. To understand changes in the RLU kinetics of firefly luciferase mutants, we used a Michaelis-Menten model with the non-steady state approximation. In this model, we do not assume that the amount of enzyme-substrate complex is at equilibrium throughout the course of the experiment. We found that one of the two mutants analyzed in this study decreases not only the dissociation rate ( koff) but also the association rate ( kon) of luciferyl-adenylate, suggesting the narrowing of the structural pocket containing the catalytic amino acids. Furthermore, comparative analysis of the nearly complete oxidation of luciferyl-adenylate with wild-type and mutant firefly luciferase reveals that the total amount of photons emitted with the mutant is 50-fold larger than that with the wild type, on average. These two results together indicate that the slow supply of luciferyl-adenylate to the enzyme increases the total number of photons emitted from the substrate, luciferyl-adenylate. Analysis with the non-steady state approximation model is generally applicable when enzymatic production kinetics are monitored in real time.

Incidence and risk factors for metabolic syndrome among urban, adult Sri Lankans: a prospective, 7-year community cohort, follow-up study

BACKGROUND

The metabolic syndrome (MetS) is a clustering of abdominal obesity, diabetes and prediabetes, high cholesterol and high blood pressure, that confers an increased risk of cardiovascular disease. There is limited data on incidence of MetS from South Asia. This study investigated incidence and risk factors for new onset MetS in an urban adult Sri Lankan population.

METHODS

Subjects (selected by age-stratified random sampling from the Ragama Medical Officer of Health area) were screened initially in 2007 (35-64 years) and re-evaluated in 2014 (42-71 years). On both occasions they were assessed by structured interview, anthropometric measurements, liver ultrasound, and biochemical/serological tests. MetS was diagnosed on International Diabetes Federation (IDF-2006) criteria. Total body fat (TBF) and visceral fat percentage (VFP) were measured in 2014, using body impedance method. Incidence and factors at baseline, associated with new onset MetS, were investigated among those who presented for re-evaluation.

RESULTS

2985 (99.1%) [1636 (54.8%) women (54.8%); median age (IQR) 53 (47-59) years] from the initial cohort in 2007 had complete data. 2148 (71.9%) [1237 (57.6%) women; median age (IQR) 60 (54-66) years] attended follow-up. 949 of them [701 (73.9%) women; median age (IQR) 60 (54-65) years] had MetS (prevalence 47.2%, 95% CI 45.0-49.4%). Of 1246 who did not have MetS in 2007, 265 [178 (67.1%) women, median age (IQR) 57 (51-64) years] had developed MetS after 7 years (annual incidence 3.5% (95% CI 2.4-4.5%). Females (OR = 4.9, 95% CI 3.4-7.4), BMI > 23 kg/m² in 2007 (OR = 1.6 per unit increase, 95% CI 1.5-1.7), weight gain (by 2-5% OR = 2.0, 95% CI 1.1-3.5; by > 5% OR = 2.2, 95% CI 1.4-3.4), and increase in waist circumference (by 2-5% OR = 7.0, 95% CI 4.0-12.2; by > 5% OR = 13.4, 95% CI 8.3-22.4) from baseline and presence of non-alcoholic fatty liver disease (NAFLD) in 2007 (OR = 1.70, 95% CI 1.04-2.76) were associated new onset MetS. Those with MetS had abnormal VFP and TBF in 2014 [P < 0.001].

CONCLUSION

In this study, annual incidence of MetS was 3.5%. Female gender, BMI > 23 kg/m² and NAFLD in 2007 and increase in weight and waist circumference from baseline were significantly associated with new onset MetS. Obesity was the best predictor of future MetS.

Lean non-alcoholic fatty liver disease (lean NAFLD): characteristics, metabolic outcomes and risk factors from a 7-year prospective, community cohort study from Sri Lanka

INTRODUCTION

While patients with non-alcoholic fatty liver disease (NAFLD) are mostly overweight or obese, some are lean.

METHODS

In a community-based follow-up study (baseline and follow-up surveys performed in 2007 and 2014), we investigated and compared the clinical characteristics, body composition, metabolic associations and outcomes, and other risk factors among individuals with lean (BMI < 23 kg/m²) NAFLD, non-lean (BMI ≥ 23 kg/m²) NAFLD and those without NAFLD. To investigate associations of selected genetic variants, we performed a case-control study between lean NAFLD cases and lean non-NAFLD controls.

RESULTS

Of the 2985 participants in 2007, 120 (4.0%) had lean NAFLD and 816 (27.3%) had non-lean NAFLD. 1206 (40.4%) had no evidence of NAFLD (non-NAFLD). Compared to non-lean NAFLD, lean NAFLD was commoner among males (p < 0.001), and had a lower prevalence of hypertension (p < 0.001) and central obesity (WC < 90 cm for males, < 80 cm for females) (p < 0.001) without prominent differences in the prevalence of other metabolic comorbidities at baseline survey. Of 2142 individuals deemed as either NAFLD or non-NAFLD in 2007, 704 NAFLD individuals [84 lean NAFLD, 620 non-lean NAFLD] and 834 individuals with non-NAFLD in 2007 presented for follow-up in 2014. There was no difference in the occurrence of incident metabolic comorbidities between lean NAFLD and non-lean NAFLD. Of 294 individuals who were non-NAFLD in 2007 and lean in both 2007 and 2014, 84 (28.6%) had developed lean NAFLD, giving an annual incidence of 4.1%. Logistic regression identified the presence of diabetes at baseline, increase in weight from baseline to follow-up and a higher educational level as independent risk factors for the development of incident lean NAFLD. NAFLD association of PNPLA3 rs738409 was more pronounced among lean individuals (one-tailed p < 0.05) compared to the whole cohort sample.

CONCLUSION

Although lean NAFLD constitutes a small proportion of NAFLD, the risk of developing incident metabolic comorbidities is similar to that of non-lean NAFLD. A PNPLA3 variant showed association with lean NAFLD in the studied population. Therefore, lean NAFLD also warrants careful evaluation and follow-up.

Accelerometric outcomes of motor function related to clinical evaluations and muscle involvement in dystrophic dogs

Duchenne muscular dystrophy (DMD) is an X-linked muscle disorder characterized by primary muscle degeneration. Patients with DMD reveal progressive muscle weakness leading to ambulatory dysfunction. Novel outcome measures are needed for more sensitive evaluation of therapeutic effects in clinical trials. Multiple parameters of acceleration and angular velocity are used as efficient indicators to quantify the motion of subjects, and these parameters have been recently applied for evaluation of motor function in DMD. In the present study, we evaluated gait in a dystrophic dog model, CXMDJ, by measuring three-axial acceleration and angular velocity over the course of months. Hybrid sensors were placed on the dorsal thoracic and lumbar regions of dogs to detect a wide range of acceleration (±8 G) and angular velocity (±1000 degrees per second). Multiple parameters showed lower values in dystrophic dogs compared to wild-type (WT) dogs, and declined over the course of months. Acceleration magnitude (AM) at the thoracic region in dystrophic dogs was prominently lower compared with WT dogs, even at the age of 2 months, the onset of muscle weakness, whereas AM at the lumbar region drastically declined throughout the disease course. The angular velocity index in the vertical direction in the lumbar region increased in dystrophic dogs, suggesting waddling at the girdle. These parameters also accordingly decreased with exacerbation of clinical manifestations and a decrease in spontaneous locomotor activity. The AM of dystrophic dogs was analyzed with magnetic resonance imaging to look for a correlation with crus muscle involvement. Results showed that acceleration and angular velocity are multifaceted kinematic indices that can be applied to assess outcomes in clinical trials for hereditary neuromuscular disorders including DMD.

Functional Analysis of Short Linear Motifs in the Plant Cyclin-Dependent Kinase Inhibitor SIAMESE

Endoreplication, a modified cell cycle in which DNA is replicated without subsequent cell division, plays an important but poorly understood role in plant growth and in plant responses to biotic and abiotic stress. The Arabidopsis (Arabidopsis thaliana) SIAMESE (SIM) gene encodes the first identified member of the SIAMESE-RELATED (SMR) family of cyclin-dependent kinase inhibitors. SIM controls endoreplication during trichome development, and sim mutant trichomes divide several times instead of endoreplicating their DNA. The SMR family is defined by several short linear amino acid sequence motifs of largely unknown function, and family members have little sequence similarity to any known protein functional domains. Here, we investigated the roles of the conserved motifs in SIM site-directed Arabidopsis mutants using several functional assays. We identified a potential cyclin-dependent kinase (CDK)-binding site, which bears no resemblance to other known CDK interaction motifs. We also identified a potential site of phosphorylation and two redundant nuclear localization sequences. Surprisingly, the only motif with similarity to the other family of plant CDK inhibitors, the INHIBITOR/INTERACTOR OF CDC2 KINASE/KIP-RELATED PROTEIN proteins, is not required for SIM function in vivo. Because even highly divergent members of the SMR family are able to replace SIM function in Arabidopsis trichomes, it is likely that the results obtained here for SIM will apply to other members of this plant-specific family of CDK inhibitors.

Effects of Trans-4-Aminomethylcyclohexane Carboxylic Acid as an Antifibrinolytic Agent on Arterial Wall and Experimental Atherosclerotic Lesions in Rabbits

Effects of trans-4-aminomethylcyclohexane carboxylic acid (t-AMCHA) as an antifibrinolytic agent on the experimental arteriosclerosis produced by cholesterol feeding and on the experimental thromboembolism induced by autogenous fibrin clot injection were observed in rabbits. Effect of inhibited fibrinolysis on the arterial wall itself was also observed.

Administration of 500 mg/kg body weight of t-AMCHA highly inhibited the lysis time of serum, but there was no influence on the plasma fibrinogen level.

There was no significant difference in the cholesterol level, sudanophilia of the aorta and the accumulation of foam cells in the aorta and pulmonary arteries between t-AMCHA + cholesterol group and cholesterol group.

Edema in the subendothelial layer of the aorta and elastic pulmonary artery, proliferation and swelling of the endothelial cells, and edema of the subendothelial layer of large muscular pulmonary arteries were increased in the incidence and severity in t-AMCHA treated animals. Localized intimai fibrous thickening was found in large muscular artery in t-AMCHA treated animals. Small fibrin thrombi and angitis were rarely found in muscular pulmonary artery in t-AMCHA treated animals.

Fibrinolytic activity of blood and dissolution of clots in the pulmonary arteries were depressed by t-AMCHA treatment in the animals injected autogenous fibrin clots, while the inflammatory reaction in the arterial wall was less severe as compared with that of untreated animals.

It was reasonable to presume that the inhibition of fibrinolysis would promote the development of atherosclerosis through its influence on the fibrin dissolution on and in the arterial wall, and on the vascular permeability of the arterial wall.