Synthesis of Sucrose-Mimicking Disaccharide by Intramolecular Aglycone Delivery

Rare sugars are known for their ability to suppress postprandial blood glucose levels. Therefore, oligosaccharides and disaccharides derived from rare sugars could potentially serve as functional sweeteners. A disaccharide [α-d-allopyranosyl-(1→2)-β-d-psicofuranoside] mimicking sucrose was synthesized from rare monosaccharides D-allose and D-psicose. Glycosylation using the intermolecular aglycon delivery (IAD) method was employed to selectively form 1,2-cis α-glycosidic linkages of the allopyranose residues. Moreover, β-selective psicofuranosylation was performed using a psicofuranosyl acceptor with 1,3,4,6-tetra-O-benzoyl groups. This is the first report on the synthesis of non-reducing disaccharides comprising only rare d-sugars by IAD using protected ketose as a unique acceptor; additionally, this approach is expected to be applicable to the synthesis of functional sweeteners.

Synthesis of azide-modified glycerophospholipid precursor analogs for detection of enzymatic reactions

Glycerophospholipids (GPLs) are major cell membrane components. Although various phosphorylated molecules are attached to lipid moieties as their headgroups, GPLs are biosynthesized from phosphatidic acid (PA) via its derivatives, diacylglycerol (DAG) or cytidine diphosphate diacylglycerol (CDP-DAG). A variety of molecular probes capable of introducing detection tags have been developed to investigate biological events involved in GPLs. In this study, we report the design, synthesis, and evaluation of novel analytical tools suitable to monitor the activity of GPL biosynthetic enzymes in vitro. Our synthetic targets, namely, azide-modified PA, azide-modified DAG, and azide-modified CDP-DAG, were successfully obtained from solketal as their common starting material. Moreover, using CDP-diacylglycerol-inositol 3-phosphatidyltransferase (CDIPT), an enzyme that catalyzed the final reaction step in synthesizing phosphatidylinositol, we demonstrated that azide-modified CDP-DAG worked as a substrate for CDIPT.

Squaryl group-modified UDP analogs as inhibitors of the endoplasmic reticulum-resident folding sensor enzyme UGGT

UDP-Glc:glycoprotein glucosyltransferase (UGGT) has a central role to retain quality control of correctly folded N-glycoprotein in the endoplasmic reticulum (ER). A selective and potent inhibitor against UGGT could lead to elucidation of UGGT-related events, but such a molecule has not been identified so far. Examples of small molecules with UGGT inhibitory activity are scarce. Here, we report squaryl group-modified UDP analogs as a promising UGGT inhibitor. Among these, the compound possessing a 2'-amino group of the uridine moiety and hydroxyethyl-substituted squaramide exhibited the highest potency, suggesting its relevance as a molecule for further optimization.

AeiA is a novel autophagy-related protein that promotes peroxisome degradation by pexophagy in Aspergillus oryzae

Autophagy is classified into nonselective and selective autophagy, depending on the specificity of substrate degradation. In the filamentous fungus Aspergillus oryzae, selective autophagy, which includes pexophagy and mitophagy, has been observed. However, the molecular mechanism underlying selective autophagy in filamentous fungi remains unclear. Here, we identified a novel protein that interacts with the autophagy-related protein Atg8 in A. oryzae, named AoAtg8-interacting protein A (AeiA). AeiA was localized to AoAtg8-positive autophagic membrane structures and peroxisomes. Moreover, peroxisomal trafficking into the vacuole was reduced in AeiA disruptants. Taken together, AeiA is a novel selective autophagy-related protein that contributes to pexophagy in A. oryzae.

Analysis of Selenoprotein F Binding to UDP-Glucose:Glycoprotein Glucosyltransferase (UGGT) by a Photoreactive Crosslinker

In the endoplasmic reticulum glycoprotein quality control system, UDP-glucose : glycoprotein glucosyltransferase (UGGT) functions as a folding sensor. Although it is known to form a heterodimer with selenoprotein F (SelenoF), the details of the complex formation remain obscure. A pulldown assay using co-transfected SelenoF and truncated mutants of human UGGT1 (HUGT1) revealed that SelenoF binds to the TRXL2 domain of HUGT1. Additionally, a newly developed photoaffinity crosslinker was selectively introduced into cysteine residues of recombinant SelenoF to determine the spatial orientation of SelenoF to HUGT1. The crosslinking experiments showed that SelenoF formed a covalent bond with amino acids in the TRXL3 region and the interdomain between βS2 and GT24 of HUGT1 via the synthetic crosslinker. SelenoF might play a role in assessing and refining the disulfide bonds of misfolded glycoproteins in the hydrophobic cavity of HUGT1 as it binds to the highly flexible region of HUGT1 to reach its long hydrophobic cavity. Clarification of the SelenoF-binding domain of UGGT and its relative position will help predict and reveal the function of SelenoF from a structural perspective.

A novel set of volatile urinary biomarkers for late-life major depressive and anxiety disorders upon the progression of frailty: a pilot study

Mood and anxiety disorders are frequent in the elderly and increase the risk of frailty. This study aimed to identify novel biomarkers of major depressive disorder (MDD) and anxiety in the elderly. We examined 639 participants in the community-dwelling Otassha Study (518 individuals considered healthy control, 77 with depression, anxiety, etc.), mean age 75 years, 58.4% of female. After exclusion criteria, we analyzed VOCs from 18 individuals (9 healthy control, 9 of MDD/agoraphobia case). Urinary volatile and semi-volatile organic compounds (VOCs) were profiled using solid-phase microextraction and gas chromatography-mass spectrometry. Six urinary VOCs differed in the absolute area of the base peak between participants with MDD and/or agoraphobia and controls. High area under the receiver-operating characteristic curve (AUC) values were found for phenethyl isothiocyanate (AUC: 0.86, p = 0.009), hexanoic acid (AUC: 0.85, p = 0.012), texanol (AUC: 0.99, p = 0.0005), and texanol isomer (AUC: 0.89, p = 0.005). The combined indices of dimethyl sulfone, phenethyl isothiocyanate, and hexanoic acid, and texanol and texanol isomer showed AUCs of 0.91 (p = 0.003) and 0.99 (p = 0.0005) and correlated with the GRID-HAMD and the Kihon Checklist (CL score), respectively. These VOCs may be valuable biomarkers for evaluating MDD and/or agoraphobia in the elderly.

Single-cell transcriptomics reveals an angiogenic cell population for therapeutic angiogenesis in adipose tissue

Background

Therapeutic angiogenesis mediated by stem/progenitor cells is an attractive therapeutic option against cardiovascular disease (CVD). Adipose tissue (AT) can be safely obtained even in CVD patients with anti-platelet medications, and it is a readily available source of culture-expanded adipose-derived stem cells (ADSCs) for transplantation. Single-cell transcriptome enables us to screen all the surface markers at once, while conventional strategies have been limited for the number of target markers. Furthermore, gene profiling at single-cell resolution can be used for the quantification of each marker by how many favorable cells can be purified without mixing of detrimental cells.

Purpose

We aimed to identify and characterize a cell population with in vivo angiogenic potential by single-cell RNA sequencing (scRNA-seq) analysis and xenograft experiments.

Methods

We revisited scRNA-seq datasets of single cell fraction from AT, bone-marrow (BM), and umbilical-cord blood (UCB, n=6/organ) to find cell populations with pro-angiogenic potential. Next, we collected AT from CVD patients (n=23) and used multicolor flow cytometry to quantify and sort the specific populations. PBS, the specific marker-negative and unsorted ADSCs were used as controls. Xenograft models of PKH26 pre-labeled human ADSC transplantation in limb ischemia were used to evaluate the lectin capillary density, PKH+ engrafted ADSCs, and blood flow recovery.

Results

Clustering divided CD45–CD31–CD34+ progenitor fraction into 3 clusters. We identified pro-/anti-angiogenic clusters based on the expressions of well-known pro-/anti-angiogenic factors. All genes encoding cell-surface proteins were compared in this functional clustering, resulted in 17 markers screened (Fig. 1A, B). Taken together with enrichment analysis, CD271+ cells showed predominant and pro-angiogenic gene profile from the other top candidates including CD36 and CD54 (Fig. 1C, D). Next, we evaluated the number and gene profile of CD271+ cells in well-known stem cell sources including BM and UCB. Surprisingly, the number of CD271 expressing cells were significantly lower and did not show angiogenic gene profile in BM and UCB (Fig. 2A). In analysis of AT from 23 CVD patients, CD271+ cells were significantly decreased by donor insulin resistance (Fig. 2B). Cell therapy using CD271+ ADSCs demonstrated in vivo angiogenic capacity compared to those of CD271– ADSCs and PBS in limb ischemia model. Furthermore, CD271+ ADSC transplantation showed enhanced efficacy compared to unsorted ADSCs from the same donors (Fig. 2C–E).

Conclusion

In this study, we identified CD271+ cell population in AT as an angiogenic cell population through scRNA-seq analysis and cell therapy experiments. AT obtained from donors without insulin resistance would be the most suitable for CD271+ ADSC isolation. CD271+ ADSC transplantation with a promising angiogenic capacity could contribute better cell-based therapy tackling CVD.

Funding Acknowledgement

Type of funding sources: Public grant(s) – National budget only. Main funding source(s): Japan Society for the Promotion of Science (JSPS) KAKENHI (Tokyo, Japan)

Phenotypic analysis of α1,2-mannosidase-like protein deletion mutants in Saccharomyces cerevisiae

α1,2‑mannosidase-like proteins mediate quality control of glycoproteins in the endoplasmic reticulum. This study explored α1,2‑mannosidase-like protein functions in Saccharomyces cerevisiae. Single disruptants in targeted protein-coding genes were found to be viable; however, deletion of MNL2 resulted in declined yeast growth at 37 °C. The normal growth rate was recovered in double-deletion strains where one of the deletions was in MNS1 . We also measured the mannosidase activity of microsomal fractions of deficient strains using artificial glycan. Increased mannose trimming activities were demonstrated by the microsomes of MNL2 -deletion strains compared to levels of activity exhibited by the microsomes of the control strain.

A compositional link between rocky exoplanets and their host stars

[Figure: see text].

Hemodynamic Analysis of Cerebral AVMs with 3D Phase-Contrast MR Imaging

BACKGROUND AND PURPOSE

The hemodynamics associated with cerebral AVMs have a significant impact on their clinical presentation. This study aimed to evaluate the hemodynamic features of AVMs using 3D phase-contrast MR imaging with dual velocity-encodings.

MATERIALS AND METHODS

Thirty-two patients with supratentorial AVMs who had not received any previous treatment and had undergone 3D phase-contrast MR imaging were included in this study. The nidus diameter and volume were measured for classification of AVMs (small, medium, or large). Flow parameters measured included apparent AVM inflow, AVM inflow index, apparent AVM outflow, AVM outflow index, and the apparent AVM inflow-to-outflow ratio. Correlation coefficients between the nidus volume and each flow were calculated. The flow parameters between small and other AVMs as well as between nonhemorrhagic and hemorrhagic AVMs were compared.

RESULTS

Patients were divided into hemorrhagic (n = 8) and nonhemorrhagic (n = 24) groups. The correlation coefficient between the nidus volume and the apparent AVM inflow and outflow was .83. The apparent AVM inflow and outflow in small AVMs were significantly smaller than in medium AVMs (P < .001 for both groups). The apparent AVM inflow-to-outflow ratio was significantly larger in the hemorrhagic AVMs than in the nonhemorrhagic AVMs (P = .02).

CONCLUSIONS

The apparent AVM inflow-to-outflow ratio was the only significant parameter that differed between nonhemorrhagic and hemorrhagic AVMs, suggesting that a poor drainage system may increase AVM pressure, potentially causing cerebral hemorrhage.

Detecting halfmetallic electronic structures of spintronic materials in a magnetic field

Band-gap engineering is one of the fundamental techniques in semiconductor technology and also applicable in next generation spintronics using the spin degree of freedom. To fully utilize the spintronic materials, it is essential to optimize the spin-dependent electronic structures in the operando conditions by applying magnetic and/or electric fields. Here we present an advanced spectroscopic technique to probe the spin-polarized electronic structures by using magnetic circular dichroism (MCD) in resonant inelastic soft X-ray scattering (RIXS) under an external magnetic field. Thanks to the spin-selective dipole-allowed transitions in RIXS-MCD, we have successfully demonstrated the direct evidence of the perfectly spin-polarized electronic structures for the prototypical halfmetallic Heusller alloy \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$\hbox {Co}_2\hbox {MnSi}$$\end{document}Co2MnSi. RIXS-MCD is a promising tool to probe the spin-dependent carriers and band-gap induced in the buried magnetic layers in an element specific way under the operando conditions.

l-tryptophan-histidine synthesis by Pseudomonas serine peptidase, an amino acid ester hydrolase of the peptidase family S9

Pseudomonas sp. KM1 produces an amino acid ester hydrolase (KM1AEH) that catalyzes peptide bond formation by acting on carboxylic ester bonds. The KM1AEH gene was cloned from genomic DNA and expressed in Escherichia coli. The recombinant enzyme (rKM1AEH) was purified, and gel filtration showed that it is a 68 kDa monomeric protein. rKM1AEH can synthesize the vasoactive dipeptide tryptophan-histidine from tryptophan methyl ester and histidine as acyl donor and acceptor, respectively. The enzyme showed maximum activity at pH 9.5 and 45 °C and was specifically inhibited by silver (Ag⁺). Mutation of the catalytic Ser459 residue in the active site of rKM1AEH with Ala, Cys, or Thr eliminated all catalytic activity. The enzyme is a novel ester hydrolase that belongs to the peptidase family S9 based on the phylogenetic analysis.

Laparoscopic and open liver resection for hepatocellular carcinoma with Child-Pugh B cirrhosis: multicentre propensity score-matched study

BACKGROUND

Laparoscopic liver resection for hepatocellular carcinoma (HCC) in Child-Pugh A cirrhosis has been demonstrated as beneficial. However, the role of laparoscopy in Child-Pugh B cirrhosis is undetermined. The aim of this retrospective cohort study was to compare open and laparoscopic resection for HCC with Child-Pugh B cirrhosis.

METHODS

Data on liver resections were gathered from 17 centres. A 1 : 1 propensity score matching was performed according to 17 predefined variables.

RESULTS

Of 382 available liver resections, 100 laparoscopic and 100 open resections were matched and analysed. The 90-day postoperative mortality rate was similar in open and laparoscopic groups (4.0 versus 2.0 per cent respectively; P = 0.687). Laparoscopy was associated with lower blood loss (median 110 ml versus 400 ml in the open group; P = 0.004), less morbidity (38.0 versus 51.0 per cent respectively; P = 0.041) and fewer major complications (7.0 versus 21.0 per cent; P = 0.010), and ascites was lower on postoperative days 1, 3 and 5. For laparoscopic resections, patients with portal hypertension developed more complications than those without (26 versus 12 per cent respectively; P = 0.002), and patients with a Child-Pugh B9 score had higher morbidity rates than those with B8 and B7 (7 of 8, 10 of 16 and 21 of 76 respectively; P < 0.001). Median hospital stay was 7.5 (range 2-243) days for laparoscopic liver resection and 18 (3-104) days for the open approach (P = 0.058). The 5-year overall survival rate was 47 per cent for open and 65 per cent for laparoscopic resection (P = 0.142). The 5-year disease-free survival rate was 32 and 37 per cent respectively (P = 0.742).

CONCLUSION

Patients without preoperative portal hypertension and Child-Pugh B7 cirrhosis may benefit most from laparoscopic liver surgery.

Serial evaluation of cardiac allograft vasculopathy after heart transplantation by dual-modality intravascular ultrasound and optical coherence tomography

Background

Cardiac allograft vasculopathy is a combination of the development of de novo plaque and the progression of donor-transmitted plaque.

Purpose

This study aimed to evaluate the development of de novo plaque and the progression of donor-transmitted plaque within 12-month after heart transplantation (HTx) using serial intravascular ultrasound (IVUS) and optical coherence tomography (OCT). The association between inflammatory cytokines and plaque progression was also examined.

Methods

We prospectively enrolled 40 recipients to conduct serial three-vessel IVUS and OCT analysis at 8-week and 12-month after HTx. De novo plaque was defined as having maximum intimal thickness (MIT) ≥0.5 mm at 12-month in the absence of donor-transmitted plaques (MIT ≥0.5 mm at 8-week). Serum cytokines were screened with a bead-based multiplex assay.

Results

A total of 13 de novo plaques (fibrous, n=10; fibroatheroma, n=3) were detected in eight recipients. Serum interleukin (IL)-31 at 8-week was associated with the development of de novo plaques (p=0.009). A total of 31 donor-transmitted plaques (fibrous, n=12; fibroatheroma, n=11; fibrocalcific, n=8) were detected in 17 recipients. Multiple regression analysis revealed that fibrous (p=0.026) and fibroatheroma (p=0.012) observed at 8-week were significantly associated with subsequent plaque progression within 12-month after HTx. ΔPlaque burden was significant higher in de novo plaque than donor-transmitted plaque (38.8% [29.6–41.2] versus 8.7% [1.3–13.6], p&lt;0.001). The prevalence of macrophage accumulation was lower in de novo plaque than in donor-transmitted plaque (8% versus 52%, p=0.006). Serum IL-31 at 8-week was correlated with the progression of donor-transmitted plaque as well as de novo plaque (r=0.663, p=0.029) although other cytokines like IL-1β, IL-6, IL-17, and tissue necrotic factor alpha were not.

Conclusions

In de novo plaques, fibrous plaque was the most common and macrophage accumulation was rarely observed. In donor-transmitted plaque, fibrous and fibroatheroma were independent predictor for the subsequent plaque progression. Serum interleukin-31 surge at subacute phase may play pathogenic role in cardiac allograft vasculopathy.

Funding Acknowledgement

Type of funding source: Public grant(s) – National budget only. Main funding source(s): Grants-in-Aid for Scientific Research (KAKENHI)

Nature of the Dirac gap modulation and surface magnetic interaction in axion antiferromagnetic topological insulator [Formula: see text]

Modification of the gap at the Dirac point (DP) in axion antiferromagnetic topological insulator [Formula: see text] and its electronic and spin structure have been studied by angle- and spin-resolved photoemission spectroscopy (ARPES) under laser excitation at various temperatures (9-35 K), light polarizations and photon energies. We have distinguished both large (60-70 meV) and reduced ([Formula: see text]) gaps at the DP in the ARPES dispersions, which remain open above the Neél temperature ([Formula: see text]). We propose that the gap above [Formula: see text] remains open due to a short-range magnetic field generated by chiral spin fluctuations. Spin-resolved ARPES, XMCD and circular dichroism ARPES measurements show a surface ferromagnetic ordering for the "large gap" sample and apparently significantly reduced effective magnetic moment for the "reduced gap" sample. These observations can be explained by a shift of the Dirac cone (DC) state localization towards the second Mn layer due to structural disturbance and surface relaxation effects, where DC state is influenced by compensated opposite magnetic moments. As we have shown by means of ab-initio calculations surface structural modification can result in a significant modulation of the DP gap.

Analysis of effects and indications of cryosurgery for oral mucoceles

Cryosurgery is a recognized method for the treatment of mucoceles in the oral cavity. In this study, cryosurgery was used for mucoceles at the lip or buccal mucosa, and the effect and the indication were evaluated clinically. The subjects were patients with a clinical diagnosis of mucocele on the lip or buccal mucosa and who chose cryosurgery after procedures for both surgical excision and cryosurgery for the lesion were explained. Cryosurgery was performed with a freezing device using liquid nitrogen without local anesthesia. Twenty-four patients chose cryosurgery, including seven preschool children. There were no serious adverse events during and after cryosurgery. Healing progress after cryosurgery was not affected by patient age, lesion size, or how long the patients had the lesion. Two cases later underwent surgical excision because cryosurgery was not successful. Twenty-three patients chose surgical excision, one case had a recurrence. The number of younger patients who chose cryosurgery was significantly higher than that who chose surgical excision. This study suggests that cryosurgery is effective for mucoceles of the lip or buccal mucosa and is a simple and safe treatment method, especially for preschool children.

P4512Impact of pulmonary artery catheter on all-cause death of patients with acute heart failure with preserved ejection fraction: Short-term results from the PURSUIT-HFpEF registry

Background

Appropriate pulmonary artery catheter (PAC) use may effectively decrease mortality in acute heart failure patients. The concept that the pulmonary artery catheter (PAC) is a valuable tool for hemodynamic monitoring when used in appropriately selected patients and by physicians trained well to interpret and apply the data correctly provided has not been evaluated adequately yet in acute heart failure patients with preserved ejection fraction (HFpEF).

Methods

The PERSUIT-HFpEF Registry is a prospective, observational, multicenter cohort study on prognosis of HFpEF in Japan. Patients hospitalized for heart failure (diagnosed by using Framingham criteria) who met both of the following criteria were enrolled: 1) a left ventricular ejection fraction of 50% or more as measured at the local site by echocardiography; 2) an elevated level of N terminal pro brain natriuretic peptide (NT proBNP) (400 pg per milliliter or more) or brain natriuretic peptide (BNP) (100 pg per milliliter or more). In the present study, we evaluated the impact of PAC on all-cause death of the patients with HFpEF. PAC use was left at the discretion of attending physicians.

Results

The PERSUIT-HFpEF Registry enrolled 486 patients (81±9 years, 259 females, mean follow-up duration 198±195 days). Of these, data of PAC usage was available in 434 patients. Patients were further stratified according to use of a PAC: PAC 153 patients vs. non-PAC 281 patients. Length of hospitalization was numerically shorter in the PAC group than in the non-PAC group [20.3±14.7 vs. 22.5±17.4 days, p=0.182]. Kaplan-Meier estimated 1-year all-cause death rate was significantly lower in the PAC group than in the non-PAC group (9.5% vs. 19.1%, p=0.019). PAC use was associated with significant risk reduction of all-cause death [hazard ratio (HR) 0.425, 95% confidence interval (CI), 0.203–0.890, p=0.023] in the crude analysis. The significant risk reduction still existed after multivariate adjustment including potential confounders [HR 0.427, 95% CI, 0.185–0.984, p=0.046]

Kaplan Meier analysis

Conclusions

In the real-world Asian registry data, PAC use was associated with the improved all-cause death rate, suggesting that the PAC might be a useful guidance tool for treatment of the patients with HFpEF.

Acknowledgement/Funding

Roche diagnostics FUJIFILM Toyama Chemical

P2590A liver-derived secretory protein, selenoprotein P causes pressure overload-induced cardiac hypertrophys

Background

Hepatokine selenoprotein P (SeP) contributes to insulin resistance and hyperglycemia in patients with type 2 diabetes. Inhibition of SeP protects the heart from ischemia reperfusion injury and serum levels of SeP are elevated in patients with heart failure with reduced ejection fraction.

Objective

We investigated the role of SeP in the regulation of cardiac remodeling in response to pressure overload.

Methods and results

To examine the role of SeP in cardiac remodeling, transverse aortic constriction (TAC) was subjected to SeP knockout (KO) and wild-type (WT) mice for 2 weeks. Hepatic expression of SeP in WT was significantly increased by TAC. LV weight/tibial length (TL) was significantly smaller in SeP KO mice than in WT mice (6.75±0.24 vs 8.33±0.32, p<0.01). Lung weight/TL was significantly smaller in SeP KO than in WT mice (10.46±0.44 vs 16.38±1.12, p<0.05). TAC-induced cardiac upregulation of the fetal type genes, including atrial and brain natriuretic factors, was significantly attenuated in SeP KO compared to WT. Furthermore, azan staining revealed that there was significantly less interstitial fibrosis in hearts after TAC in SeP KO than in WT mice. To determine whether hepatic overexpression of SeP affects TAC-induced cardiac hypertrophy, a hydrodynamic injection method was used to generate mice that overexpress SeP mRNA in the liver. Hepatic overexpression of SeP in SeP KO mice lead to a significant increase in LV weight/TL and Lung weight/TL after TAC compared to that in other SeP KO mice.

Conclusions

These results suggest that cardiac pressure overload induced hepatic expression of SeP and the absence of endogenous SeP attenuated cardiac hypertrophy, dysfunction and fibrosis in response to pressure overload in mice. SeP possibly plays a maladaptive role against progression of heart failure through the liver-heart axis.

Emerging investigator series: investigation of mercury emission sources using Hg isotopic compositions of atmospheric mercury at the Cape Hedo Atmosphere and Aerosol Monitoring Station (CHAAMS), Japan

This study conducted mercury (Hg) isotopic analysis, which has been expected as a new indicator for understanding the behavior of atmospheric Hg. The dominant atmospheric Hg species, namely gaseous elemental mercury (GEM, Hg0), were collected at the Cape Hedo Atmosphere and Aerosol Monitoring Station (CHAAMS) in Okinawa, Japan, for evaluating possible source(s) and transformation process(es) of Hg. The Hg isotopic compositions of GEM samples showed that the mass-dependent fractionation (MDF) of δ202Hg and the mass-independent fractionation (MIF) of Δ199Hg ranged from -2.15‰ to 0.79‰ and from -0.32‰ to 0.00‰, respectively. The results were classified into two groups: (1) negative δ202Hg and near-zero Δ199Hg in summer and (2) near-zero δ202Hg and negative Δ199Hg in the other season. According to the NOAA Hybrid Single-Particle Lagrangian Integrated Trajectory (HYSPLIT) model, the dominant air masses traveled from East Asia during winter and South and East Asia during summer. However, the air masses also traveled from mainland Japan and rotated around Okinawa before reaching CHAAMS. In contrast, clear positive correlations between δ202Hg values and CO and PM2.5 concentrations were observed during summer. A small peak of Ox concentration was observed at three atmospheric monitoring stations, namely Nago, Naha, and Miyako Island during summer. Since Miyako Island is located ∼370 km southwest of CHAAMS, the main emission source of GEM transported to CHAAMS was not from mainland Okinawa but traveled from the southwest during summer.

Medication-related osteonecrosis of the jaw after tooth extraction in cancer patients: a multicenter retrospective study

Root amputation, immunosuppressive therapy, mandibular tooth extraction, pre-existing inflammation, and longer duration of treatment with bone-modifying agents were significantly associated with an increased risk of medication-related osteonecrosis of the jaw. Hopeless teeth should be extracted without drug holiday before the development of inflammation in cancer patients receiving high-dose bone-modifying agents.

INTRODUCTION

No studies have comprehensively analyzed the influence of pre-existing inflammation, surgical procedure-related factors such as primary wound closure, demographic factors, and drug holiday on the incidence of medication-related osteonecrosis of the jaw (MRONJ). The purpose of this study was to retrospectively investigate the relationships between these various factors and the development of MRONJ after tooth extraction in cancer patients receiving high-dose bone-modifying agents (BMAs) such as bisphosphonates or denosumab.

METHODS

Risk factors for MRONJ after tooth extraction were evaluated with univariate and multivariate analyses. The following parameters were investigated in all patients: demographics, type and duration of BMA use, whether BMA use was discontinued before tooth extraction (drug holiday), the duration of such discontinuation, the presence of pre-existing inflammation, and whether additional surgical procedures (e.g., incision, removal of bone edges, root amputation) were performed.

RESULTS

We found that root amputation (OR = 22.62), immunosuppressive therapy (OR = 16.61), extraction of mandibular teeth (OR = 12.14), extraction of teeth with pre-existing inflammation, and longer duration (≥ 8 months) of high-dose BMA (OR = 7.85) were all significantly associated with MRONJ.

CONCLUSIONS

Tooth extraction should not necessarily be postponed in cancer patients receiving high-dose BMA. The effectiveness of a short-term drug holiday was not confirmed, as drug holidays had no significant impact on MRONJ incidence. Tooth extraction may be acceptable during high-dose BMA therapy until 8 months after initiation.

Characterization and Thermal Denaturation Kinetic Analysis of Recombinant l-Amino Acid Ester Hydrolase from Stenotrophomonas maltophilia

Stenotrophomonas maltophilia HS1 exhibits l-amino acid ester hydrolase (SmAEH) activity, which can synthesize dipeptides such as Ile-Trp, Val-Gly, and Trp-His from the corresponding amino acid methyl esters and amino acids. The gene encoding SmAEH was cloned and expressed in Escherichia coli and was purified and characterized. SmAEH shared 77% sequence identity with a known amino acid ester hydrolase (AEH) from Xanthomonas citri, which belongs to a class of β-lactam antibiotic acylases. The thermal stability of SmAEH was evaluated using various mathematical models to assess its industrial potential. First-order kinetics provided the best description for the inactivation of the enzyme over a temperature range of 35-50 °C. Decimal reduction time ranged from 212.76 to 3.44 min, with a z value of 8.06 °C, and the deactivation energy was 204.1 kJ mol^-1.

Pectin RG-I rhamnosyltransferases represent a novel plant-specific glycosyltransferase family

Pectin is one of the three key cell wall polysaccharides in land plants and consists of three major structural domains: homogalacturonan, rhamnogalacturonan I (RG-I) and RG-II. Although the glycosyltransferase required for the synthesis of the homogalacturonan and RG-II backbone was identified a decade ago, those for the synthesis of the RG-I backbone, which consists of the repeating disaccharide unit [→2)-α-L-Rha-(1 → 4)-α-D-GalUA-(1→], have remained unknown. Here, we report the identification and characterization of Arabidopsis RG-I:rhamnosyltransferases (RRTs), which transfer the rhamnose residue from UDP-β-L-rhamnose to RG-I oligosaccharides. RRT1, which is one of the four Arabidopsis RRTs, is a single-spanning transmembrane protein, localized to the Golgi apparatus. RRT1 was highly expressed during formation of the seed coat mucilage, which is a specialized cell wall with abundant RG-I. Loss-of-function mutation in RRT1 caused a reduction in the level of RG-I in the seed coat mucilage. The RRTs belong to a novel glycosyltransferase family, now designated GT106. This is a large plant-specific family, and glycosyltransferases in this family seem to have plant-specific roles, such as biosynthesis of plant cell wall polysaccharides.

Enzymatic and molecular characterization of α-1,3-glucanase (AglST2) from Streptomyces thermodiastaticus HF3-3 and its relation with α-1,3-glucanase HF65 (AglST1)

Extracellular α-1,3-glucanase HF90 (AglST2), with a sodium dodecyl sulfate (SDS)-PAGE-estimated molecular mass of approximately 91 kDa, was homogenously purified from the culture filtrate of Streptomyces thermodiastaticus HF3-3. AglST2 showed a high homology with mycodextranase in an amino acid sequence and demonstrated specificity with an α-1,3-glycosidic linkage of homo α-1,3-glucan. It has been suggested that AglST2 may be a new type of α-1,3-glucanase. The optimum pH and temperature of AglST2 were pH 5.5 and 60°C, respectively. AglST2 action was significantly stimulated in the presence of 5-20% (w/v) NaCl, and 1 mM metal ions Mn²⁺ and Co²⁺. On the other hand, it was inhibited by 1 mM of Ag⁺, Cu²⁺, Fe²⁺ and Ni²⁺. Regarding the stability properties, AglST2 retained more than 80% of its maximum activity over a pH range of 5.0-7.0 at up to 60°C and in the presence of 0-20% (w/v) NaCl. Based on these results, the properties of AglST2 were comparable with those of AglST1, which had been previously purified and characterized from S. thermodiastaticus HF3-3 previously. The N-terminal amino acid sequence of AglST2 showed a good agreement with that of AglST1, suggesting that AglST1 was generated from AglST2 by proteolysis during cultivation. MALDI-TOF mass analysis suggested that AglST1 might be generated from AglST2 by the proteolytic removal of C-terminus polypeptide (approximately 20 kDa). Our investigation thus revealed the properties of AglST2, such as tolerance against high temperature, salts, and surfactants, which have promising industrial applications.

Studies of Fibrinogen Metabolism in Healthy and Hypertensive Female Subjects with the Use of Autologous I-125-Fibrinogen

10 healthy female subjects and 15 female patients with essential hypertension were studied with respect to fibrinogen metabolism in a steady state. Autologous I-125-labeled fibrinogen (I-125-fibrinogen) was used as a tracer. Comparison of the results showed that plasma volume, t½ of plasma I-125-fibrinogen and fractional catabolic rate (j3p) of plasma fibrinogen were not appreciably different in both groups of subjects, but plasma fibrinogen concentration, and catabolic flux of (synthesis rate) were significantly higher in hypertensive subjects, whereas extravascular fibrinogen and fractional transcapillary transfer rate (j1) of were significantly decreased in the patients. Further analyses of the data in both groups showed that there were significant correlations between diastolic blood pressure (P) and j1 with a regression equation of j1 = e−0.0285P, between 1 and between and j1 with a regression equation of 1. These results indicate that the observed decrease of j1 triggered the transition from normal to pathological steady state and is responsible for the altered metabolism and distribution of fibrinogen in hypertensive subjects.

Effects of Heparin, Typhoid Vaccine and Thrombophlebitis on Factor X Metabolism in the Dog

Studies were made of the effects of heparin, typhoid vaccine and thrombophlebitis on factor X (F.X) metabolism in dogs, using 125-labelled F.X (125I-F.X) as a tracer. 10 healthy male dogs were used for control study and 5 male dogs were used for each of other studies. Plasma F.X concentration was measured by a solid-phase radioimmunoassay. In the control dogs, the plasma F.X concentration was 2.4 ± 0.2 (SD) mg per dl, the plasma F.X (x) was 1.2 ± 0.1(SD) mg per kg, the halflife of plasma 125I-F.X(t½) was 0.5 ± 0.01 (SD) days, the fractional catabolic rate (j3p) was 2.4 ± 0.1 (SD) per day and the catabolic flur (J3pX) (synthesis rate) was 2.9 ± 0.7 (SD) mg per kg per day. These results were not appreciably altered in heparinized dogs. However, a single intravenous injection of 2 ml typhoid vaccine caused a shortened t½ of 0.38 ± 0.01 (SD) days and a decrease of plasma F.X concentration to 1.3 ± 0.13 (SD) mg per dl. Studies in heparinized dogs showed similar effects of typhoid vaccine. Next, thrombophlebitis was produced by a previous method and its effects on F.X metabolism were studied. No detectable alterations of F.X metabolism were found. These results indicate that in health most F. X is directly catabolized without the formation of activated F.X (F.Xa), that the observed effects of typhoid vaccine are mostly due to an acceleration of the direct catabolism of F.X without F.Xa formation and finally that localized thrombophlebitis has no appreciable effects on F.X metabolism.

Studies of Heparin Affinity to Antithrombin III and Other Proteins in Vitro and in Vivo

Properties of human, canine, and porcine heparin and S-35-heparin were first studied. Their electrophoretic mobility through 10 g % polyacrylamide gels, specific activity and their filtration patterns through Sephadex G-200 columns were closely similar. Then, S-35-heparin (0.5 mg) and cold heparin (27 mg) were simultaneously injected intravenously into 5 dogs and their plasma behavior was compared. The plasma half-lives of S-35-heparin averaged 1.18 ± 0. 13 (SD) hr and was identical with that of cold heparin, but the half-lives were much shorter and averaged 0.46 ± 0.08 (SD) hr in 5 dogs when S-35-heparin alone was injected. Studies were next made of heparin affinity to proteins including canine antithrombin III (AT) by the use of Sephadex G-200 chromatography, polyacrylamide gel electrophoresis, and S-35-heparin as a tracer. It was found that S-35-heparin-binding to alpha1, beta, and gammaglobulins and fibrinogen was readily separable upon addition of 5 mg cold heparin, but that the binding to AT was inseparable by addition of cold heparin or by electrophoresis. However, in canine plasma, both S-35-heparin and cold heparin were mostly bound to proteins other than AT, suggesting that this might be the case in vivo. To further substantiate this, studies were made of the comparative behavior of I-125-labeled AT (I-125-AT) and S-35-heparin in dogs with the idea that the plasma half-lives of both should be equal if they were irreversibly bound to each other. The plasma half-lives of I-125-AT averaged 2.10 ± 0.05 (SD) days in 5 male dogs and 1.99 ± 0.04 (SD) days in 5 female dogs, and were much different from the half-life values of S-35-heparin as given above. These results indicate that heparin in vitro is more tightly bound to AT than to other proteins, that heparin in vivo is not irreversibly bound to AT and suggest that it is mostly bound to proteins other than AT in vivo.

Studies of the Effects of Estradiol, Progesterone, Cortisol, Thrombophlebitis, and Typhoid Vaccine on Synthesis and Catabolism of Antithrombin III in the Dog

Effects of estradiol, progesterone, Cortisol, thrombophlebitis and typhoid vaccine on the synthesis and catabolism of antithrombin III (AT) in dogs were studied, using I-125-labeled AT (I-125-AT) as a tracer. Five dogs were used for each study. A single intramuscular injection of 20 mg estradiol caused a 20% decrease of plasma AT concentration in 6 days without appreciable changes in the plasma half-lives of I-125-AT but with a significant decrease in the fractional catabolic rate of I-125-AT (j3u). A single intramuscular injection of 250 mg progesterone did not produce any appreciable changes of plasma AT concentration, the plasma half-lives of I-125-AT or j3u. On the other hand, intravenous and intramuscular injections of a total of 750 mg Cortisol caused a 17 % increase of plasma AT concentration in a day after the injections without alterations of the plasma half-lives of I-125-AT or j3u. Next, thrombophlebitis was produced in dogs by a single intravenous injection of 1 ml 90% phenol into a leg vein occluded for 1 min by a gauze tourniquet and the effects of thrombophlebitis were studied. The results indicated that it did not cause appreciable changes of plasma AT concentration, the plasma half-lives of I-125-AT or j3u. However, studies of the effects of a single intravenous injection of 3 ml typhoid vaccine showed a 25 % decrease of plasma AT concentration in a day after the injection with a moderate acceleration of the decline rate of plasma I-125-AT and a 14% increase in j3u values. Further studies in heparinized dogs showed similar effects with typhoid vaccine. These results indicate that estradiol causes a decreased rate of AT synthesis, that progesterone has no appreciable effects on AT metabolism, that Cortisol increases the rate of AT synthesis, that localized thrombophlebitis has no appreciable effects on AT metabolism and that typhoid vaccine causes an increased j3u by unknown mechanisms which is not an accelerated coagulation process.

Properties of Human Tissue Thromboplastins from Brain, Lung, Arteries, and Placenta

Properties of purified and delipidated human tissue thromboplastins (TTPs) from brain (BTTP), lung (LTTP), arteries (ATTP) and placenta (PTTP) were studied. The extinction coefficients were closely similar with a mean value of 8.3 ± 0.01 (SD). The molecular weights were 200,000 ± 3,000 (SD) (BTTP), 90,000 ± 2,000 (SD) (LTTP), 110,000 ± 3,000 (SD) (ATTP) and 250,000 ± 4,000 (SD) (PTTP). The maximum activity of each delipidated TTP after relipidation was obtained when phospholipid-delipidated TTP ratio was 2.0, and the maximum specific activity was 440 units per mg BTTP, 270 units per mg LTTP, 80 units per mg ATTP and 600 units per mg PTTP. Ouchterlony analysis with anti-delipidated PTTP antibody showed the reaction of partial identity between delipidated TTPs and the antibody. Studies of the reactivity of I-125-delipidated TTPs with the antibody gave the following average values for % bound I-125-TTPs in 2 hours: 3.6± 0.2 (SD) % (I-125-BTTP), 11.0± 0.3 (SD) % (I-125-LTTP), 4.4±0.2 (SD) % (I-125-ATTP) and 13.7±0.3 (SD) % (I-125-PTTP). It was also found that the antibody markedly neutralized the coagulant activity of saline extracts of brain, lung and placenta. These results indicate that delipidated BTTP, LTTP, ATTP and PTTP are different while being similar in some aspects and that complete TTPs are not coated with lipids in a manner inaccessible to anti-delipidated PTTP antibody.

Studies of the Metabolism and Distribution of Prothrombin in Healthy Men with Homologous 125I-Prothrombin

A method was described for preparation of purified human prothrombin using repeated barium citrate adsorption and citrate elution, (NH4)2S04 fractionation, Sephadex chromatography and isoelectric precipitation. The produced prothrombins were then physicochemically analyzed. The extinction coefficient was 12.7 ± 0.82 (SD) and the specific activity, 2,563 ± 420 (SD) Iowa units per mg prothrombin. The amino acid composition in g% was as follows: aspartic acid, 8.64; threonine, 5.87; serine, 4.16; glutamic acid, 11.15; proline, 3.91; glycine, 3.96; alanine, 4.65; half cystine, 4.68; valine, 4.46; methionine, 1.14; isoleucine, 2.93; leucine, 6.18; tyrosine, 4.52; phenylalanin, 4.19; lysine, 4.78; histidine, 1.73; ammonia, 1.85; arginine, 6.91. The tryptophan and carbohydrate contents were not determined. The prothrombins were then labeled with 125I in a ratio of about 0.25 atom iodine per molecule of prothrombin and were used for studies of the metabolism and distribution of prothrombin in thirteen healthy men. A model was proposed for the human prothrombin system based on the assumptions that prothrombin is catabolized intravascularly without the formation of thrombin, and was tested against the observed behavior of injected 125I- prothrombin. The model closely predicted the observed behavior of 125I-prothrombin. The analytical results of the tracer data in thirteen healthy men by the methods derived from the model were as follows: The plasma prothrombin, 6.65 ± 1.10 (SD) mg per kg; the interstitial prothrombin, 6.0 ^ 1.9 (SD) mg per kg; the half-life of plasma 125I-prothrombin, 2.29 ± 0.14 (SD) days ; the transcapillary transfer rate of prothrombin, 10.2 ± 3.9 (SD) mg per kg per day; and the catabolic (synthetic) rate of prothrombin, 4.3 J: 1.0 (SD) mg per kg per day. These results support the concept that in healthy men prothrombin is degraded in plasma or spaces in rapid exchange with it generation of appreciable amounts of thrombin.