Palladium-Catalyzed Reductive Heck Hydroarylation of Unactivated Alkenes Using Hydrosilane at Room Temperature

The reductive Heck hydroarylation of unactivated alkenes has emerged as an essential reaction for regioselective hydroarylation. Herein, we report a palladium-catalyzed reductive Heck hydroarylation of unactivated alkenes under mild conditions with enhanced functional group tolerance using hydrosilane as the reducing reagent. Under the optimal conditions, the alkylarene yields increased, resulting in minimal undesired products. Mechanistic studies using deuterated reagents indicated the involvement of two competing catalytic cycles.

Hydrolytic dynamic kinetic resolution of racemic 3-phenyl-2-oxetanone to chiral tropic acid

Tropic acid was synthesized in a good yield and with high enantioselectivity (81% ee) under non-biphasic conditions via the novel hydrolytic dynamic kinetic resolution of racemic 3-phenyl-2-oxetanone (tropic acid β-lactone) in the presence of a chiral quaternary ammonium phase-transfer catalyst and strongly basic anion exchange resin as the hydroxide ion donor.

POS0841 HIGH-INTENSITY INDUCTION THERAPY COMBINING TOFACITINIB, RITUXIMAB, AND PLASMAPHERESIS IN RAPIDLY PROGRESSIVE INTERSTITIAL LUNG DISEASE ASSOCIATED WITH ANTI-MDA5 ANTIBODY POSITIVE DERMATOMYOSITIS

Background

Rapidly progressive interstitial lung disease (RP-ILD) associated with anti-melanoma differentiation-associated protein 5 (MDA5) autoantibody (Ab) -positive dermatomyositis (DM) is one of the most life-threatening autoimmune conditions. The clinical course is very rapid, leading to death within three months after the onset of symptoms. Although triple therapy which consists of corticosteroids, cyclophosphamide, and tacrolimus has been considered as standard therapy and additional treatments including plasma exchange (PE) and rituximab (RTX) have been reported, the survival rate of patients with poor prognostic factors is still poor even if all of these treatments were applied. Recently, there exist increasing evidences regarding the efficacy of tofacitinib (TOF) in refractory DM. We have treated anti-MDA5Ab-positive RP-ILD with multiple poor prognostic factors with high-intensity induction therapy which combined triple therapy, PE, RTX, and TOF.

Objectives

This study aimed to investigate the therapeutic efficacy of high-intensity induction therapy for patients with anti-MDA5Ab-positive RP-ILD with multiple poor prognostic factors.

Methods

31 patients who were diagnosed with anti-MDA5Ab-positive DM during 2014 to 2021 in our institution were included in this study. The clinical characteristics for poor prognosis were retrospectively analyzed, and the outcomes of high-intensity induction therapy were analyzed for the survival and adverse events.

Results

17 cases were treated before the introduction of TOF. Although triple therapy with RTX, PE, or intravenous immunoglobulin (IVIG) were used, eight out of 10 RP-ILD cases with a ferritin level >400 ng/mL (range, 402.5-5,831; mean, 2,342 ± 2,069) died in median 2.5 months. Poor prognosis was predicted by followings; elevated levels of serum ferritin, lactate dehydrogenase, transaminases, creatinine phosphokinase, and C-reactive protein; decrease in platelets, serum albumin, and oxygen saturation; use of oxygen; higher age; shorter disease duration to admission. The addition of RTX and PE was not enough to control RP-ILD in anti-MDA5Ab positive DM, and prevention of the initial exacerbation of ILD following induction therapy was considered to be important. Based on these observations, high-intensity induction therapy was consisted as follows; triple therapy with decreasing the dose of methylprednisolone by half from 1g to 1 mg/kg, liposteroid to suppress macrophage activity, TOF, PE, and RTX. High-intensity induction therapy was applied in eight patients (ferritin levels; range, 412.2-7,095 ng/mL; mean, 3,558±3,152 ng/mL) with multiple poor prognostic factors described above. Although deaths at two months and eight months due to ILD were observed, significant improvement of survival was documented (Figure 1). Two patients in whom RTX was not initially administered, exacerbation of ILD was observed one month later, which prompted the use of RTX. Several adverse events were observed in high-intensity induction therapy. The most common events were reactivation of cytomegalovirus, meanwhile herpes zoster was not documented. Sustained leukocytopenia and thrombocytopenia were observed in three patients, and two patients developed thrombotic microangiopathy which led to the discontinuation of tacrolimus. Fungal infections in lung were also documented. These adverse events were controllable.

Figure 1.

Conclusion

Significant improvement of survival was observed in patients treated with high-intensity induction therapy. Meanwhile, stratification of patients for poor prognosis would be important.

References

None

Disclosure of Interests

None declared

The feasible maintenance dose of corticosteroid in Takayasu arteritis in the era of biologic therapy

Objective: Although biologic agents are used in Takayasu arteritis (TAK), corticosteroids are still the mainstay of treatment. This study aimed to investigate the feasible maintenance dose of prednisolone (PSL) in the biologic therapy era.Method: We enrolled 93 patients with TAK who satisfied the criteria of the American College of Rheumatology and visited our department from 2008 to 2018. The clinical characteristics and PSL dose of the patients were retrospectively evaluated.Results: The mean ± sd maintenance dose of PSL was 5.0 ± 3.0 mg/day. In patients having TAK for > 20 years, PSL discontinuation and drug-free status were achieved in 27.2% and 18%, respectively. Although tapering the PSL dose to 10 mg/day was achieved within 12 months, tapering to 5 mg/day required 10 years. Relapse significantly interfered with the PSL dose reduction. The clinical characteristics of patients with relapse included a lower rate of combination therapy using immunosuppressants. Moreover, biologics were used in > 60% of patients with relapse. Tapering of PSL was significantly possible in patients receiving biologics and additional relapse was observed in 6.3% and 50% of patients with and without biologics, respectively. Such PSL-sparing effect enabled the reduction of the median PSL dose from 10 to 5 mg/day. Steroid discontinuation was achieved in some patients.Conclusions: The use of biologics significantly reduced the PSL dose in relapsed patients. A PSL dose of ≤ 5 mg/day is a feasible target for TAK, especially when biologic agents are used. Nevertheless, corticosteroid discontinuation may also be the target in some patients.

Resurrecting the ancient glow of the fireflies

The color of firefly bioluminescence is determined by the structure of luciferase. Firefly luciferase genes have been isolated from more than 30 species, producing light ranging in color from green to orange-yellow. Here, we reconstructed seven ancestral firefly luciferase genes, characterized the enzymatic properties of the recombinant proteins, and determined the crystal structures of the gene from ancestral Lampyridae. Results showed that the synthetic luciferase for the last common firefly ancestor exhibited green light caused by a spatial constraint on the luciferin molecule in enzyme, while fatty acyl-CoA synthetic activity, an original function of firefly luciferase, was diminished in exchange. All known firefly species are bioluminescent in the larvae, with a common ancestor arising approximately 100 million years ago. Combined, our findings propose that, within the mid-Cretaceous forest, the common ancestor of fireflies evolved green light luciferase via trade-off of the original function, which was likely aposematic warning display against nocturnal predation.

FRI0189 ENDOTHELIAL PROTEIN C RECEPTOR AND SCAVENGER RECEPTOR CLASS B TYPE 1 NEGATIVELY REGULATE ENDOTHELIAL ACTIVATION AND REPRESENT NOVEL AUTOANTIGENS IN TAKAYASU ARTERITIS

Background:

Takayasu arteritis (TAK) is a chronic granulomatous vasculitis and affects large vessels in young female. It has been recognized that high numbers of patients with TAK possessed autoantibodies against vascular endothelium, which are called anti-endothelial cell antibodies (AECAs). Although their target antigens had not been identified for a long time, we utilized an expression cloning system for specific identification of cell-surface antigens and successufully identified endothelial protein C receptor (EPCR) and scavenger receptor class B type 1 (SR-BI) as major novel autoantigens in TAK. It was possible that identified novel autoantibodies were utilized for clinical application and elucidating pathomechanisms of TAK.

Objectives:

To reveal the clinical impact and pathogenic potential of novel autoantibodies in TAK

Methods:

Three hundred twenty-five patients with autoimmune diseases were enrolled: 80, TAK; 10, giant cell arteritis (GCA); and 235, other autoimmune diseases. The expressions of EPCR and SR-BI were examined in the aortic tissue from several diseases by immunohistochemistry. The presence of novel autoantibodies was measured in TAK and other autoimmune diseases. Clinical characteristics of patients with these autoantibodies were evaluated in TAK. To investigate the pathogenetic potential of these novel autoantibodies, vascular endothelial cells from umbilical vein, aortic artery, and pulmonary artery were examined for the endothelial cell activation. The effects of the novel autoantibodies upon the differentiation of immune cells were also evaluated.

Results:

In non-inflammatory aortic tissue, the expressions of EPCR and SR-BI were observed in the endothelium of vasa vasorum. Their expressions in the endothelium were augumented in TAK tissue. Novel autoantibodies against EPCR or SR-BI were detected in 34.6 % or 36.5 % of cases, respectively in TAK, and overlap was obsereved only in two cases, indicating their exclusive nature. These autoantibodies were specific for TAK among autoimmune rheumatic diseases, and they were not detected in patients with GCA with cranial involvement, suggesting different pathomechanisms among these diseases. The clinical characteristics of patients with anti-EPCR autoantibodies included high prevalence of stroke and ulcerative colitis. Surprisingly, anti-EPCR autoantibodies were also detected in patients with primary ulcerative colitis, suggesting their common pathomechanisms with TAK. Serial measurement of these novel autoantibodies revealed their correlation with disease activity of TAK. In machanistic studies, EPCR and SR-BI functioned as negative regulators of endothelial activation and chemokine production. EPCR further functioned in human T cells and ameliorated Th17 differentiation. Autoantibodies against EPCR and SR-BI blocked the functions of their targets, thereby promoting pro-inflammatory phenotype.

Conclusion:

EPCR and SR-BI are preferentially expressed in the endothelium of vaso vasorum and upregulated in TAK tissue. Autoantibodies against EPCR or SR-BI are specific for TAK among autoimmune rheumatic conditions and detected in about 70 % of TAK, suggesting their usefulness for the diagnosis, subclassification, and monitoring of TAK. Autoantibodies inhibit the resolution of activated immune responses and thus would lead to the chronic vascular inflammation.

References:

[1]Shirai T et al. Arthritis Res Ther 2012;14:R157.

[2]Shirai T et al. Clin Dev Immunol 2013;2013:453058.

[3]Shirai T et al. J Neuroinflammation. 2013;10:128

Disclosure of Interests:

None declared

Experimental study on monitoring system of clinical beam purity in multiple-ion beam operation for heavy-ion radiotherapy

The National Institute of Radiological Sciences has investigated multiple-ion therapy using energetic beams of helium, carbon, oxygen, and neon ions, to improve treatment outcomes of refractory cancer. For this therapy, it is necessary to ensure the helium-ion beam purity to avoid irradiation by unwanted ions. Here, we develop a measurement method for monitoring beam purity. This method can measure the charge number of the ions in a high-purity beam using an ionization chamber and Faraday cup. In addition, it can be used to detect the contamination of the clinical helium-ion beam. We perform beam experiments to evaluate our beam-purity monitoring method and predict that our method is capable of detecting contamination below 1%.

Talbot-Lau interferometry-based x-ray imaging system with retractable and rotatable gratings for nondestructive testing

We develop an x-ray imaging system based on Talbot-Lau interferometry equipped with a mechanical structure for retracting and rotating gratings from the optical axis, which enables not only x-ray phase contrast imaging but also conventional x-ray imaging with high-magnification such as microcomputed tomography (μCT). We investigate the characterization of carbon fiber reinforced plastic (CFRP) laminates using this apparatus. Microcracks and fiber orientations are visualized in the dark-field images. Compared with the obtained μCT images, the relationship between the CFRP microstructures and the contrasts in the dark-field images are recognizable.

The cosmic ray energy spectrum measured with the new Tibet hybrid experiment

We have upgraded the new Tibet ASgamma experiment in China since 2014 to measure the chemical composition of cosmic rays around the knee. This hybrid experiment consist of an air-shower-core detector array (YAC-II) to detect high energy electromagnetic component, the Tibet air-shower array (Tibet-III) and a large underground water-Cherenkov muon-detector array (MD). We have carried out a detailed air-shower Monte Carlo (MC) simulation to study the performance of the hybrid detectors by using CORSIKA (version 7.5000), which includes EPOS-LHC, QGSJETII-04, SIBYLL2.1 and SIBYLL2.3 hadronic interaction models. The preliminary results of the interaction model checking above 50 TeV energy region are reported in this paper, and the primary proton and helium spectra in the energy range 50 TeV to 1015 eV was derived from YAC-I data and is smoothly connected with direct observation data at lower energies and also with our previously reported works at higher energies within statistical errors. The knee of the (P+He) spectra is located around 400 TeV. The interaction model dependence in deriving the primary (P+He) spectra is found to be small (less than 25% in absolute intensity, 10% in position of the knee), and the composition model dependence is less than 10% in absolute intensity.

Ion-production efficiency of a singly charged ion source developed toward a 11C irradiation facility for cancer therapy

The ion-production efficiency of a newly developed singly charged ion source (SCIS) has been investigated to discuss the possibility of it being used in an isotope separation on-line system that provides ¹¹C ions for heavy-ion cancer therapy with simultaneous verification of the irradiation field using positron emission tomography. The SCIS uses a low-energy hollow electron beam to produce singly charged carbon ions efficiently. To deliver sufficient ¹¹C ions to the treatment room from a limited amount of ¹¹C molecules, which are produced from a boron compound target and proton-beam irradiation via the ¹¹B(p,n)¹¹C reaction, the SCIS must have high ion-production efficiency. To realize this high efficiency, the SCIS was designed using a three-dimensional particle-in-cell code in previous work. With the fabricated SCIS, we performed experiments to measure the efficiency of producing CO₂ ⁺ ions from nonradioactive ¹²CO₂ molecules and C⁺ ions from nonradioactive ¹²CH₄ molecules. We found that the SCIS achieved efficiencies of ε_C⁺ =4×10^-3 (0.4%) for C⁺ production and ε_{CO2 ⁺} =0.107 (10.7%) for CO₂ ⁺ production.

Test of the hadronic interaction models SIBYLL2.3, EPOS-LHC and QGSJETII- 04 with Tibet EAS core data

A hybrid experiment has been started by the ASγ experiment at Yangbajing (4300m a.s.l.) in Tibet since May 2009, that consists of a high-energy air-shower-core array (YAC-I) and a high-density air-shower array (Tibet-III). In this paper, we report our results to check the hadronic interaction models SIBYLL2.3, SIBYLL2.1, EPOS-LHC and QGSJETII-04 in the multi-tens TeV energy region using YAC-I+Tibet-III experimental data from May 2009 through January 2010. The effective live time is calculated as 106.05 days. The results show that the description of transverse momentum, inelastic cross-section and inelasticity for the 4 hadronic interaction models is consistent with YAC-I experimental data within 15% systematic errors range in the forward region below 100 TeV. Among them, the EPOS-LHC model is the best hadronic interaction model. Furthermore, we find that the H4a composition model is the best one below the 100 TeV energy region.

On the Solar Cycle Variation of the Solar Diurnal Anisotropy of Multi-TeV Cosmic-ray Intensity Observed with the Tibet Air Shower Array

We analyze the temporal variation of the solar diurnal anisotropy of the multi-TeV cosmic-ray intensity observed with the Tibet air shower array from 2000 to 2009, covering the maximum and minimum of the 23rd solar cycle. We comfirm that a remarkable additional anisotropy component is superposed on the Compton-Getting anisotropy at 4.0 TeV, while its amplitude decreases at higher energy regions. In constrast to the additional anisotropy reported by the Matsushiro experiment at 0.6 TeV, we find the residual component measured by Tibet at multi-TeV energies is consistent with being stable, with a fairly constant amplitude of 0.041% ± 0.003% and a phase at around 07.17 ± 00.16 local solar time at 4.0 TeV. This suggests the additional anisotropy observed by the Tibet experiment could result from mechanisms unrelated to solar activities.

Singly charged ion source designed using three-dimensional particle-in-cell method

A singly charged ion source (SCIS) has been designed using a newly developed three-dimensional particle-in-cell (PIC) code. The SCIS is to be used in an isotope separation on-line (ISOL) system that provides ¹¹C ions for heavy-ion cancer therapy with simultaneous verification of the dose distribution using positron emission tomography. The SCIS uses low-energy electron beams to produce singly charged carbon ions efficiently and maintain a high vacuum in the ISOL system. Because the SCIS has to realize a production efficiency of 1% if its carbon ions are to be used in the ISOL system, a suitable design for the SCIS was investigated by using the developed PIC code to study the beam trajectories of the electrons and extracted ions. The simulation results show that hollow electron beams are produced in the designed SCIS resulting in a high effective electron current. The results also predict that the designed SCIS would realize ion-production efficiencies (IPEs) of ε _SCIS ≃ 6.7% for C O 2 + production from CO₂ gas and ε _SCIS ≃ 0.1% for C⁺ production from CH₄ gas. Moreover, to examine the validity of the developed code and confirm that the SCIS was able to be designed appropriately, the space-charge-limited current of the electron gun and the total IPE obtained by adding the IPEs of each ion were compared between the experiment and the simulation.

Identification of patterns of factors preceding severe or life-threatening asthma exacerbations in a nationwide study

BACKGROUND

Reducing near-fatal asthma exacerbations is a critical problem in asthma management.

OBJECTIVES

To determine patterns of factors preceding asthma exacerbations in a real-world setting.

METHODS

In a nationwide prospective study of 190 patients who had experienced near-fatal asthma exacerbation, cluster analysis was performed using asthma symptoms over the 2-week period before admission.

RESULTS

Three distinct clusters of symptoms were defined employing the self-reporting of a visual analogue scale. Cluster A (42.1%): rapid worsening within 7.4 hours from moderate attack to admission, young to middle-aged patients with low Body mass index and tendency to depression who had stopped anti-asthma medications, smoked, and hypersensitive to environmental triggers and furred pets. Cluster B (40.0%): fairly rapid worsening within 48 hours, mostly middle-aged and older, relatively good inhaled corticosteroid (ICS) or ICS/long-acting beta-agonist (LABA) compliance, and low perception of dyspnea. Cluster C (17.9%): slow worsening over 10 days before admission, high perception of dyspnea, smokers, and chronic daily mild-moderate symptoms. There were no differences in overuse of short-acting beta-agonists, baseline asthma severity, or outcomes after admission for patients in these 3 clusters.

CONCLUSION

To reduce severe or life-threatening asthma exacerbation, personalized asthma management plans should be considered for each cluster. Improvement of ICS and ICS/LABA compliance and cessation of smoking are important in cluster A. To compensate for low perception of dyspnea, asthma monitoring of peak expiratory flow rate and/or exhaled nitric oxide would be useful for patients in cluster B. Avoidance of environmental triggers, increase usual therapy, or new anti-type 2 response-targeted therapies should be considered for cluster C.

Functional characterization of recombinant snake venom rhodocytin: rhodocytin mutant blocks CLEC-2/podoplanin-dependent platelet aggregation and lung metastasis

Essentials We generated recombinant rhodocytin that could aggregate platelets via CLEC-2. Recombinant wild-type rhodocytin formed heterooctamer with four α- and β-subunits. Asp 4 in α-subunit of rhodocytin was required for binding to CLEC-2. Inhibitory mutant of rhodocytin blocked podoplanin-dependent hematogenous metastasis.

SUMMARY

Background Rhodocytin, a disulfide-linked heterodimeric C-type lectin from Calloselasma rhodostoma consisting of α-subunits and β-subunits, induces platelet aggregation through C-type lectin-like receptor 2 (CLEC-2). CLEC-2 is a physiological binding partner of podoplanin (PDPN), which is expressed on some tumor cell types, and is involved in tumor cell-induced platelet aggregation and tumor metastasis. Thus, modified rhodocytin may be a possible source of anti-CLEC-2 drugs for both antiplatelet and antimetastasis therapy. However, its molecular function has not been well characterized, because of the lack of recombinant rhodocytin that induces platelet aggregation. Objective To produce recombinant rhodocytin, in order to verify its function with mutagenesis, and to develop an anti-CLEC-2 drug based on the findings. Methods We used Chinese hamster ovary cells to express recombinant rhodocytin (wild-type [WT] and mutant), which was analyzed for induction/inhibition of platelet aggregation with light transmission aggregometry, the formation of multimers with blue native PAGE, and binding to CLEC-2 with flow cytometry. Finally, we investigated whether mutant rhodocytin could suppress PDPN-induced metastasis in an experimental lung metastasis mouse model. Results Functional WT] rhodocytin (αWTβWT) was obtained by coexpression of both subunits. Asp4 in α-subunits of rhodocytin was required for CLEC-2 binding. αWTβWT formed a heterooctamer similarly to native rhodocytin. Moreover, an inhibitory mutant of rhodocytin (αWTβK53A/R56A), forming a heterotetramer, bound to CLEC-2 without inducing platelet aggregation, and blocked CLEC-2-PDPN interaction-dependent platelet aggregation and experimental lung metastasis. Conclusion These findings provide molecular characterization information on rhodocytin, and suggest that mutant rhodocytin could be used as a therapeutic agent to target CLEC-2.

Targeting Ras-Driven Cancer Cell Survival and Invasion through Selective Inhibition of DOCK1

Oncogenic Ras plays a key role in cancer initiation but also contributes to malignant phenotypes by stimulating nutrient uptake and promoting invasive migration. Because these latter cellular responses require Rac-mediated remodeling of the actin cytoskeleton, we hypothesized that molecules involved in Rac activation may be valuable targets for cancer therapy. We report that genetic inactivation of the Rac-specific guanine nucleotide exchange factor DOCK1 ablates both macropinocytosis-dependent nutrient uptake and cellular invasion in Ras-transformed cells. By screening chemical libraries, we have identified 1-(2-(3'-(trifluoromethyl)-[1,1'-biphenyl]-4-yl)-2-oxoethyl)-5-pyrrolidinylsulfonyl-2(1H)-pyridone (TBOPP) as a selective inhibitor of DOCK1. TBOPP dampened DOCK1-mediated invasion, macropinocytosis, and survival under the condition of glutamine deprivation without impairing the biological functions of the closely related DOCK2 and DOCK5 proteins. Furthermore, TBOPP treatment suppressed cancer metastasis and growth in vivo in mice. Our results demonstrate that selective pharmacological inhibition of DOCK1 could be a therapeutic approach to target cancer cell survival and invasion.

Evaluation of the Interplanetary Magnetic Field Strength Using the Cosmic-Ray Shadow of the Sun

We analyze the Sun's shadow observed with the Tibet-III air shower array and find that the shadow's center deviates northward (southward) from the optical solar disk center in the "away" ("toward") interplanetary magnetic field (IMF) sector. By comparing with numerical simulations based on the solar magnetic field model, we find that the average IMF strength in the away (toward) sector is 1.54±0.21_{stat}±0.20_{syst} (1.62±0.15_{stat}±0.22_{syst}) times larger than the model prediction. These demonstrate that the observed Sun's shadow is a useful tool for the quantitative evaluation of the average solar magnetic field.

A clustering approach to identify and characterize the asthma and chronic obstructive pulmonary disease overlap phenotype

BACKGROUND

Asthma and chronic obstructive pulmonary disease (COPD) are heterogeneous diseases. The phenotypes that have clinical features of both asthma and COPD are still incompletely understood.

OBJECTIVE

To clarify the best discriminators of the asthma-COPD overlap phenotype from asthma and COPD subgroups using a clustering approach.

METHODS

This study assessed pathophysiological parameters, including mRNA expression levels of T helper cell-related transcription factors, namely TBX21 (Th1), GATA3 (Th2), RORC (Th17) and FOXP3 (Treg), in peripheral blood mononuclear cells in asthma patients (n=152) and in COPD patients (n=50). Clusters were determined using k-means clustering. Exacerbations of asthma and COPD were recorded during the 1-year follow-up period.

RESULTS

The cluster analysis revealed four biological clusters: cluster 1, predominantly patients with COPD; cluster 2, patients with an asthma-COPD overlap phenotype; cluster 3, patients with non-atopic and late-onset asthma; and cluster 4, patients with early-onset atopic asthma. Hazard ratios for exacerbation were 2.5 (95% confidence interval [CI], 1.1-5.6) in cluster 1 and 2.3 (95% CI, 1.0-5.0) in cluster 2 compared with patients in other clusters. Cluster 2 was discriminated from other clusters by total serum IgE level ≥310 IU/mL, blood eosinophil counts ≥280 cells/μL, a higher ratio of TBX21/GATA3, FEV₁ /FVC ratio <0.67 and smoking ≥10 pack-years with an area under the curve of 0.94 (95% CI, 0.90-0.98) in the receiver operating characteristic analysis.

CONCLUSIONS AND CLINICAL RELEVANCE

The asthma-COPD overlap phenotype was characterized by peripheral blood eosinophilia and higher levels of IgE despite the Th2-low endotype.

The platelet-activating receptor C-type lectin receptor-2 plays an essential role in liver regeneration after partial hepatectomy in mice

Essentials Regeneration role of C-type lectin receptor-2 (CLEC-2) after 70% hepatectomy (HPx) was investigated. Wild-type or CLEC-2 deleted from platelets of chimeric mice (flKO) underwent HPx. The liver/body weight ratio was significantly lower in the flKO than in the wild-type. CLEC-2 plays an essential role in liver regeneration after HPx.

SUMMARY

Background and aim The aim of the present study was to investigate the role of C-type lectin receptor (CLEC)-2 in liver regeneration following partial liver resection in mice. Materials and methods Irradiated chimeric mice transplanted with fetal liver cells from wild-type (WT) mice, CLEC-2-deleted (KO) mice or mice with CLEC-2 deleted specifically from platelets (flKO) were generated. Mice underwent 70% partial hepatectomy (PH). Immunohistochemical staining was performed to investigate the expression of the endogenous ligand for CLEC-2, podoplanin. The accumulation of platelets in the liver was also quantified. The hepatic expression of the IL-6/gp130 and STAT3, Akt and ERK1/2 was also examined. Results The liver/body weight ratio and expression of all cell proliferation markers were significantly lower in the flKO group than in the WT group. The expression of phosphorylated (p) Akt and pERK1/2 was similar in the WT and flKO groups. On the other hand, the expression of pSTAT3 and IL-6 was significantly stronger in the WT group than in the flKO group. The expression of podoplanin was detected in the hepatic sinusoids of both groups. However, the extent to which platelets accumulated in hepatic sinusoids was significantly less in the flKO group than in the WT group. Conclusion CLEC-2 was involved in hepatic regeneration after liver resection and CLEC-2-related liver regeneration was attributed to the interaction between platelets and sinusoidal endothelial cells.

A decadal inversion of CO2 using the Global Eulerian-Lagrangian Coupled Atmospheric model (GELCA): sensitivity to the ground-based observation network

We present an assimilation system for atmospheric carbon dioxide (CO₂) using a Global Eulerian-Lagrangian Coupled Atmospheric model (GELCA), and demonstrate its capability to capture the observed atmospheric CO₂ mixing ratios and to estimate CO₂ fluxes. With the efficient data handling scheme in GELCA, our system assimilates non-smoothed CO₂ data from observational data products such as the Observation Package (ObsPack) data products as constraints on surface fluxes. We conducted sensitivity tests to examine the impact of the site selections and the prior uncertainty settings of observation on the inversion results. For these sensitivity tests, we made five different site/data selections from the ObsPack product. In all cases, the time series of the global net CO₂ flux to the atmosphere stayed close to values calculated from the growth rate of the observed global mean atmospheric CO₂ mixing ratio. At regional scales, estimated seasonal CO₂ fluxes were altered, depending on the CO₂ data selected for assimilation. Uncertainty reductions (URs) were determined at the regional scale and compared among cases. As measures of the model-data mismatch, we used the model-data bias, root-mean-square error, and the linear correlation. For most observation sites, the model-data mismatch was reasonably small. Regarding regional flux estimates, tropical Asia was one of the regions that showed a significant impact from the observation network settings. We found that the surface fluxes in tropical Asia were the most sensitive to the use of aircraft measurements over the Pacific, and the seasonal cycle agreed better with the results of bottom-up studies when the aircraft measurements were assimilated. These results confirm the importance of these aircraft observations, especially for constraining surface fluxes in the tropics.

C-type lectin-like receptor 2 promotes hematogenous tumor metastasis and prothrombotic state in tumor-bearing mice

Essentials The role of C-type lectin-like receptor-2 (CLEC-2) in cancer progression is unclear. CLEC-2-depleted mouse model is generated by using a rat anti-mouse CLEC-2 monoclonal antibody. CLEC-2 depletion inhibits hematogenous tumor metastasis of podoplanin-expressing B16F10 cells. CLEC-2 depletion prolongs cancer survival by suppressing thrombosis and inflammation.

SUMMARY

Background C-type lectin-like receptor 2 (CLEC-2) is a platelet activation receptor of sialoglycoprotein podoplanin, which is expressed on the surface of certain types of tumor cells. CLEC-2-podoplanin interactions facilitate hematogenous tumor metastasis. However, direct evidence of the role of CLEC-2 in hematogenous metastasis and cancer progression is lacking. Objective and methods We generated immunological CLEC-2-depleted mice by using anti-mouse CLEC-2 monoclonal antibody 2A2B10 and investigated whether CLEC-2 promoted hematogenous tumor metastasis and tumor growth and exacerbated the prognosis of mice bearing podoplanin-expressing B16F10 melanoma cells. Results Our results showed that hematogenous metastasis was significantly inhibited in CLEC-2-depleted mice. B16F10 cells co-cultured with wild-type platelets, but not with CLEC-2-deficient platelets, showed increased proliferation. However, B16F10 cell proliferation was not inhibited in CLEC-2-depleted mice. Histological analysis showed that thrombus formation in tumor vessels was significantly inhibited and functional vessel density was significantly increased in CLEC-2-depleted mice. These data suggest that CLEC-2 deficiency may inhibit thrombus formation in tumor vessels and increase the density of functional vessels, thus improving oxygen and nutrient supply to tumors, indirectly promoting tumor proliferation. Furthermore, the overall survival of CLEC-2-depleted mice was significantly prolonged, which may be due to the suppression of thrombus formation in the lungs and subsequent inhibition of systemic inflammation and cachexia. Conclusions These data provide a rationale for the targeted inhibition of CLEC-2 as a new strategy for preventing hematogenous tumor metastasis and for inhibiting cancer-related thromboembolism.

Severe or life-threatening asthma exacerbation: patient heterogeneity identified by cluster analysis

BACKGROUND

Severe or life-threatening asthma exacerbation is one of the worst outcomes of asthma because of the risk of death. To date, few studies have explored the potential heterogeneity of this condition.

OBJECTIVES

To examine the clinical characteristics and heterogeneity of patients with severe or life-threatening asthma exacerbation.

METHODS

This was a multicentre, prospective study of patients with severe or life-threatening asthma exacerbation and pulse oxygen saturation < 90% who were admitted to 17 institutions across Japan. Cluster analysis was performed using variables from patient- and physician-orientated structured questionnaires.

RESULTS

Analysis of data from 175 patients with severe or life-threatening asthma exacerbation revealed five distinct clusters. Cluster 1 (n = 27) was younger-onset asthma with severe symptoms at baseline, including limitation of activities, a higher frequency of treatment with oral corticosteroids and short-acting beta-agonists, and a higher frequency of asthma hospitalizations in the past year. Cluster 2 (n = 35) was predominantly composed of elderly females, with the highest frequency of comorbid, chronic hyperplastic rhinosinusitis/nasal polyposis, and a long disease duration. Cluster 3 (n = 40) was allergic asthma without inhaled corticosteroid use at baseline. Patients in this cluster had a higher frequency of atopy, including allergic rhinitis and furred pet hypersensitivity, and a better prognosis during hospitalization compared with the other clusters. Cluster 4 (n = 34) was characterized by elderly males with concomitant chronic obstructive pulmonary disease (COPD). Although cluster 5 (n = 39) had very mild symptoms at baseline according to the patient questionnaires, 41% had previously been hospitalized for asthma.

CONCLUSIONS & CLINICAL RELEVANCE

This study demonstrated that significant heterogeneity exists among patients with severe or life-threatening asthma exacerbation. Differences were observed in the severity of asthma symptoms and use of inhaled corticosteroids at baseline, and the presence of comorbid COPD. These findings may contribute to a deeper understanding and better management of this patient population.

Top-down assessment of the Asian carbon budget since the mid 1990s

Increasing atmospheric carbon dioxide (CO₂) is the principal driver of anthropogenic climate change. Asia is an important region for the global carbon budget, with 4 of the world's 10 largest national emitters of CO₂. Using an ensemble of seven atmospheric inverse systems, we estimated land biosphere fluxes (natural, land-use change and fires) based on atmospheric observations of CO₂ concentration. The Asian land biosphere was a net sink of −0.46 (−0.70–0.24) PgC per year (median and range) for 1996–2012 and was mostly located in East Asia, while in South and Southeast Asia the land biosphere was close to carbon neutral. In East Asia, the annual CO₂ sink increased between 1996–2001 and 2008–2012 by 0.56 (0.30–0.81) PgC, accounting for ∼35% of the increase in the global land biosphere sink. Uncertainty in the fossil fuel emissions contributes significantly (32%) to the uncertainty in land biosphere sink change.

Land biosphere uptake of carbon is important in mitigating the anthropogenic increase in atmospheric CO₂ and its climate forcing. Here, the authors show that land biosphere uptake of carbon in Asia has increased substantially since the mid 1990s, likely owing to reforestation and regional climate change.

Improved optical properties of silica/UV-cured polymer composite films made of hollow silica nanoparticles with a hierarchical structure for light diffuser film applications

This study successfully improved the optical properties of silica/UV-cured polymer composite films made of hollow silica nanoparticles having a hierarchical structure.

Role of Quantum and Surface-State Effects in the Bulk Fermi-Level Position of Ultrathin Bi Films

We performed high-resolution photon-energy and polarization-dependent ARPES measurements on ultrathin Bi(111) films [6-180 bilayers (BL), 2.5-70 nm thick] formed on Si(111). In addition to the extensively studied surface states (SSs), the edge of the bulk valence band was clearly measured by using S-polarized light. We found direct evidence that this valence band edge, which forms a hole pocket in the bulk Bi crystal, does not cross the Fermi level for the 180 BL thick film. This is consistent with the predicted semimetal-to-semiconductor transition due to the quantum-size effect [V.B. Sandomirskii, Sov. Phys. JETP 25, 101 (1967)]. However, it became metallic again when the film thickness was decreased (below 30 BL). A plausible explanation for this phenomenon is the modification of the charge neutrality condition due to the size effect of the SSs.

IgA nephropathy: clinicopathology and immunopathology

In a total of 283 biopsies, 100 (35%) were found to be IgA nephropathy. The incidence reached 40% among primary glomerulonephropathies. On the basis of histopathologic changes in glomeruli, these biopsies were classified into 3 groups. The criteria employed correlated well with clinical, laboratory and immunofluorescent findings. Immune complex pathogenesis was discussed in relation to our findings.

Effect of secondary particles on image quality of dynamic flat panels in carbon ion scanning beam treatment

OBJECTIVE

Real-time markerless tumour tracking using radiographic fluoroscopic imaging is one of the better solutions to improving respiratory-gated radiotherapy. However, particle beams cause secondary particles from patients, which could affect radiographs. Here, we evaluated the quality of radiographs during carbon ion pencil beam scanning (CPBS) irradiation for respiratory gating.

METHODS

A water phantom and chest phantom were used. The phantoms were irradiated with CPBS at 290 MeV n(-1) from orthogonal directions. Dose rates were 3.4 × 10(8), 1.14 × 10(8) and 3.79 × 10(7) particles per second. A dynamic flat panel detector (DFPD) was installed on the upstream (DFPD1) or downstream (DFPD2) side of the vertical irradiation port. DFPD images were acquired during CPBS at 15.00, 7.50 and 3.75 frames per second (fps). Charge on the DFPD was cleaned using fast readout technique every 30 fps. DFPD images were acquired during CPBS with radiographic exposure, and results with and without fast readout technique were compared.

RESULTS

Secondary particles were visualized as spots or streak-like shapes. Capture of secondary particles from the horizontal beam direction was lower with fast readout technique than without it. With regard to beam irradiation direction dependency, CPBS from the horizontal direction resulted in a greater magnitude of secondary particles reaching DFPD2 than reaching DFPD1. When CPBS was delivered from the vertical direction, however, the magnitude of secondary particles on both DFPDs was very similar.

CONCLUSION

Fast readout technique minimized the effect of secondary particles on DFPD images during CPBS.

ADVANCES IN KNOWLEDGE

This technique may be useful for markerless tumour tracking for respiratory gating.

Implementation of a target volume design function for intrafractional range variation in a particle beam treatment planning system

OBJECTIVE

Treatment planning for charged particle therapy in the thoracic and abdominal regions should take account of range uncertainty due to intrafractional motion. Here, we developed a design tool (4Dtool) for the target volume [field-specific target volume (FTV)], which accounts for this uncertainty using four-dimensional CT (4DCT).

METHODS

Target and normal tissue contours were input manually into a treatment planning system (TPS). These data were transferred to the 4Dtool via the picture archiving and communication system (PACS). Contours at the reference phase were propagated to other phases by deformable image registration. FTV was calculated using 4DCT on the 4Dtool. The TPS displays FTV contours using digital imaging and communications in medicine files imported from the PACS. These treatment parameters on the CT image at the reference phase were then used for dose calculation on the TPS. The tool was tested in single clinical case randomly selected from patients treated at our centre for lung cancer.

RESULTS

In this clinical case, calculation of dose distribution with the 4Dtool resulted in the successful delivery of carbon-ion beam at the reference phase of 95% of the prescribed dose to the clinical target volume (CTV). Application to the other phases also provided sufficient dose to the CTV.

CONCLUSION

The 4Dtool software allows the design of the target volume with consideration to intrafractional range variation and is now in routine clinical use at our institution.

ADVANCES IN KNOWLEDGE

Our alternative technique represents a practical approach to four-dimensional treatment planning within the current state of charged particle therapy.

The long-term outcome following the use of frozen autograft treated with liquid nitrogen in the management of bone and soft-tissue sarcomas

In 1999, we developed a technique for biological reconstruction after excision of a bone tumour, which involved using autografts of the bone containing the tumour treated with liquid nitrogen. We have previously reported the use of this technique in 28 patients at a mean follow up of 27 months (10 to 54).

In this study, we included 72 patients who underwent reconstruction using this technique. A total of 33 patients died and three were lost to follow-up, at a mean of 23 months (2 to 56) post-operatively, leaving 36 patients available for a assessment at a mean of 101 months 16 to 163) post-operatively. The methods of reconstruction included an osteo-articular graft in 16, an intercalary in 13 and, a composite graft with prosthesis in seven.

Post-operative function was excellent in 26 patients (72.2%), good in seven (19.4%), and fair in three (8.3%) according to the functional evaluation system of Enneking. No recurrent tumour occurred within the grafts. The autografts survived in 29 patients (80.6%), and the rates of survival at five and ten years were 86.1% and 80.6 %, respectively. Seven of 16 osteo-articular grafts (44%) failed because of fracture or infection, but all the composite and intercalary grafts survived.

The long-term outcomes of frozen autografting, particularly using composite and intercalary grafts, are satisfactory and thus represent a good method of treatment for patients with a sarcoma of bone or soft tissue.

Cite this article: Bone Joint J 2014;96-B:555–61.