Radiative pumping in a strongly coupled microcavity filled with a neat molecular film showing excimer emission

Strong light-matter interactions have attracted much attention as a means to control the physical/chemical properties of organic semiconducting materials with light-matter hybrids called polaritons. To unveil the processes under strong coupling, studies on the dynamics of polaritons are of particular importance. While highly condensed molecular materials with large dipole density are ideal to achieve strong coupling, the emission properties of such films often become a mixture of monomeric and excimeric components, making the role of excimers unclear. Here, we use amorphous neat films of a new bis(phenylethynyl anthracene) derivative showing only excimer emission and investigate the excited-state dynamics of a series of strongly coupled microcavities, with each cavity being characterised by a different exciton-photon detuning. A time-resolved photoluminescence study shows that the excimer radiatively pumps the lower polariton in the relaxation process and the decay profile reflects the density of states. The delayed emission derived from triplet-triplet annihilation is not sensitive to the cavity environment, possibly due to the rapid excimer formation. Our results highlight the importance of controlling intermolecular interactions towards rational design of organic exciton-polariton devices, whose performance depends on efficient polariton relaxation pathways.

Formate-producing capacity provided by reducing ability of Streptococcus thermophilus nicotinamide adenine dinucleotide oxidase determines yogurt acidification rate

Yogurt is made by fermenting milk with 2 lactic acid bacteria, Lactobacillus delbrueckii ssp. bulgaricus and Streptococcus thermophilus. To comprehensively understand the protocooperation mechanism between S. thermophilus and L. bulgaricus in yogurt fermentation, we examined 24 combinations of cocultures comprising 7 fast- or slow-acidifying S. thermophilus strains with 6 fast- or slow-acidifying L. bulgaricus strains. Furthermore, 3 NADH oxidase (Nox)-deficient mutants (Δnox) and one pyruvate formate-lyase deficient mutant (ΔpflB) of S. thermophilus were used to evaluate the factor that determines the acidification rate of S. thermophilus. The results revealed that the acidification rate of S. thermophilus monoculture determined the yogurt fermentation rates, despite the coexistence of L. bulgaricus, whose acidification rate was either fast or slow. Significant correlation was found between the acidification rate of S. thermophilus monoculture and the amount of formate production. Result using ΔpflB showed that the formate was indispensable for the acidification of S. thermophilus. Moreover, results of the Δnox experiments revealed that formate production required Nox activity, which not only regulated dissolved oxygen, but also the redox potential. The Nox provided the large decrease in redox potential required by pyruvate formate-lyase to produce formate. A highly significant correlation was found between formate accumulation and Nox activity in S. thermophilus. In conclusion, the formate production ability provided by the action of Nox activity determines the acidification rate of S. thermophilus, and consequently, regulates yogurt coculture fermentation.

Pentraxin 3 is an adipose tissue-related serum marker for pancreatic cancer cachexia predicting subsequent muscle mass and visceral fat loss

Cancer cachexia, a paraneoplastic syndrome characterized by ongoing skeletal muscle mass loss, is accompanied by adipose tissue loss and strongly affects chemotherapy endurance. Our aim was to detect a serum marker reflecting pancreatic cancer cachexia and predicting subsequent loss of muscle mass and adipose tissue, focusing on adipose tissue-secreted proteins. Murine-derived pancreatic cancer cells were orthotopically injected into the mouse pancreatic tail. After 3 weeks, RNA sequencing of perigonadal fat and orthotopic tumors was carried out. We analyzed stocked sera and clinical data of metastatic pancreatic cancer patients who received chemotherapy. Perigonadal fat weight/body weight decreased in mice with orthotopic tumors compared to those without tumors. By RNA sequencing and real-time PCR validation, pentraxin 3 (PTX3) was identified as a secreted protein-encoded gene whose expression was significantly higher in the perigonadal fat of mice with orthotopic tumors than in that of mice without orthotopic tumors and was least expressed in orthotopic tumors. Serum PTX3 levels correlated with PTX3 mRNA levels in perigonadal fat and were higher in mice with orthotopic tumors than in those without tumors. In 84 patients diagnosed with metastatic pancreatic cancer, patients with high serum PTX3 levels showed a greater visceral fat loss/month and skeletal muscle mass index (SMI) decrease/month than those with low serum PTX3 levels. High serum PTX3 was an independent risk factor for visceral fat loss, decreased SMI, and poor prognosis. High serum PTX3 in pancreatic cancer patients predicts visceral fat and muscle mass loss and major clinical outcomes of cancer cachexia.

Recyclable optical bioplastics platform for solid state red light harvesting via triplet-triplet annihilation photon upconversion

Sustainable photonics applications of solid-state triplet-triplet annihilation photon upconversion (TTA-UC) are limited by a small UC spectral window, low UC efficiency in air, and non-recyclability of polymeric materials used. In a step to overcome these issues, we have developed new recyclable TTA-UC bioplastics by encapsulating TTA-UC chromophores liquid inside the semicrystalline gelatin films showing broad-spectrum upconversion (red/far-red to blue) with high UC efficiency in air. For this, we synthesized a new anionic annihilator, sodium-TIPS-anthracene-2-sulfonate (TIPS-AnS), that combined with red/far-red sensitizers (PdTPBP/Os(m-peptpy)₂(TFSI)₂), a liquid surfactant Triton X-100 reduced (TXr) and protein gelatin (G) formed red/far-red to blue TTA-UC bioplastic films just by air drying of their aqueous solutions. The G-TXr-TIPS-AnS-PdTPBP film showed record red to blue (633 to 478 nm) TTA-UC quantum yield of 8.5% in air. The high UC quantum yield has been obtained due to the fluidity of dispersed TXr containing chromophores and oxygen blockage by gelatin fibers that allowed efficient diffusion of triplet excited chromophores. Further, the G-TXr-TIPS-AnS-Os(m-peptpy)₂(TFSI)₂ bioplastic film displayed far-red to blue (700-730 nm to 478 nm) TTA-UC, demonstrating broad-spectrum photon harvesting. Finally, we demonstrated the recycling of G-TXr-TIPS-AnS-PdTPBP bioplastics by developing a downstream approach that gives new directions for designing future recyclable photonics bioplastic materials.

Prediction of clinical outcomes in patients with coronavirus disease 2019 using high-sensitive troponin I and N-terminal pro-B-type natriuretic peptide

Background

Several comorbidities, including cardiovascular diseases or myocardial injury, are reported to be associated with poor prognosis in patients with Coronavirus disease 2019 (COVID-19). However, detailed prognostic analysis of myocardial injury by various biomarkers in COVID-19 patients is limited.

Purpose

This study aims to explore the prognostic values of high-sensitive Troponin I (hsTnI) and N-terminal pro-B-type natriuretic peptide (NT-proBNP) for COVID-19 patients using Japanese real-world data.

Methods

The COVID-MI study is a retrospective cohort study that enrolls consecutive laboratory-confirmed COVID-19 patients admitted to the hospital from July 2020 to September 2021. We collected clinical data, including cardiac biomarker values, by chart review. If the prespecified biomarkers in concern were not available, we measured them using the institutional serum blood bank, which enrolled patients prospectively from July 2020. Patients with available biomarkers were analyzed according to the values of hsTnI or NT-proBNP, using the clinically relevant thresholds (hsTnI: 5 ng/L and 99th percentile of the upper reference limit [99%ile URL], and NT-proBNP: 125 pg/mL and 900 pg/mL). The primary outcome measure was all-cause death. Secondary outcome measures included acute respiratory distress syndrome, myocardial infarction, myocarditis/pericarditis, venous thromboembolism, cerebral infarction, and bleeding events.

Results

We enrolled 917 patients with COVID-19 confirmed by viral nucleic acid amplification test. The mean age was 61 years, and 591 patients (64%) were men. On admission, the number of patients classified as severe or critical COVID-19 was 515 (56%) and 85 (8.7%), respectively. Among the 544 patients with hsTnI values, 365 (67%) patients had elevated hsTnI of ≥5 ng/L, and 134 patients (25%) had TnI of ≥99%ile URL. Besides, among 546 patients with NT-proBNP values, 295 patients (54%) had elevated NT-pro-BNP of ≥125 pg/mL, and 93 patients (17%) had NT-proBNP of ≥900 pg/mL. The median follow-up period was 31 days (interquartile range: 11–90 days). In cumulative incidence analysis, higher levels of hsTnI and NT-proBNP were associated with significantly higher mortality (hsTnI: <5 ng/L group; 8.8%, 5 ng/L to 99%ile URL group; 19%, and ≥99%ile URL group; 37%, P<0.001, and NT-proBNP: <125 pg/mL group; 7.8%, 125 to 900 pg/mL group; 21%, and ≥900 pg/mL group; 45%, P<0.001). The adjusted risk for all-cause death remained significant for each threshold of cardiac biomarkers (hsTnI ≥99%ile URL: hazard ratio [HR] 1.98, 95% confidence interval [CI] 1.11–3.54, P=0.02, and NT-proBNP ≥900 pg/mL: HR 3.60, 95% CI 1.86–6.98, P<0.001).

Conclusion

Elevation of hsTnI or NT-proBNP was associated with poor prognosis in the current relatively severely ill COVID-19 patients. Measuring hsTnI or NT-proBNP can be an attractive option for risk stratification and deciding appropriate management in patients with COVID-19.

Funding Acknowledgement

Type of funding sources: Public hospital(s). Main funding source(s): Institutional Research Fund at Kobe City Medical Center General Hospital

STAT3 is Activated by CTGF-mediated Tumor-stroma Cross Talk to Promote HCC Progression

BACKGROUND & AIMS

Signal transducer and activator of transcription 3 (STAT3) is known as a pro-oncogenic transcription factor. Regarding liver carcinogenesis, however, it remains controversial whether activated STAT3 is pro- or anti-tumorigenic. This study aimed to clarify the significance and mechanism of STAT3 activation in hepatocellular carcinoma (HCC).

METHODS

Hepatocyte-specific Kras-mutant mice (Alb-Cre Kras^LSL-G12D/+; Kras^G12D mice) were used as a liver cancer model. Cell lines of hepatoma and stromal cells including stellate cells, macrophages, T cells, and endothelial cells were used for culture. Surgically resected 12 HCCs were used for human analysis.

RESULTS

Tumors in Kras^G12D mice showed up-regulation of phosphorylated STAT3 (p-STAT3), together with interleukin (IL)-6 family cytokines, STAT3 target genes, and connective tissue growth factor (CTGF). Hepatocyte-specific STAT3 knockout (Alb-Cre Kras^LSL-G12D/+ STAT3^fl/fl) downregulated p-STAT3 and CTGF and suppressed tumor progression. In coculture with stromal cells, proliferation, and expression of p-STAT3 and CTGF, were enhanced in hepatoma cells via gp130/STAT3 signaling. Meanwhile, hepatoma cells produced CTGF to stimulate integrin/nuclear factor kappa B signaling and up-regulate IL-6 family cytokines from stromal cells, which could in turn activate gp130/STAT3 signaling in hepatoma cells. In Kras^G12D mice, hepatocyte-specific CTGF knockout (Alb-Cre Kras^LSL-G12D/+ CTGF^fl/fl) downregulated p-STAT3, CTGF, and IL-6 family cytokines, and suppressed tumor progression. In human HCC, single cell RNA sequence showed CTGF and IL-6 family cytokine expression in tumor cells and stromal cells, respectively. CTGF expression was positively correlated with that of IL-6 family cytokines and STAT3 target genes in The Cancer Genome Atlas.

CONCLUSIONS

STAT3 is activated by CTGF-mediated tumor-stroma crosstalk to promote HCC progression. STAT3-CTGF positive feedback loop could be a therapeutic target.

Virulence plasmids in clinical isolates of Rhodococcus equi from sick foals in the Netherlands

Clinical samples from 123 foals with suspected rhodococcosis submitted to the Veterinary Microbiological Diagnostic Centre of the Faculty of Veterinary Medicine between 1993 and 2006 were tested for the presence of the virulence gene vapA. Of the 123 samples, 120 were vapA-positive and 3 vapA-negative Rhodococcus equi were isolated. The 120 vapA-positive R. equi were isolated from 70 tracheal wash, 19 lung tissues, 7 lymph nodes, 6 synovial fluids, 13 abscesses or pus and single isolates from the uterus, gut, cerebrospinal fluid, abdomen fluid and faeces. Of the 120 isolates, 46 were from Dutch warmblood horses, 23 from Friesian horses, 14 from Trotters, 4 from Holsteiners, 3 from Arab breed, 2 from ponies, 1 from a Welsh pony and 27 from undefined breed horses. Using plasmid profile analysis of the 120 isolates, 117 isolates contained the 85-kb type I plasmid, 2 contained the 87-kb type I plasmid and 1 contained the novel 52-kb non-mobilizable virulence plasmid reported recently. These results showed that the virulent R. equi strains harbouring a virulence plasmid of 85-kb type I or 87-kb type I, which have been detected in clinical isolates from five European countries, are widespread in the Netherlands. This is the first report of plasmid types of clinical R. equi isolates in the Netherlands.

Serum growth differentiation factor 15 predicts hepatocellular carcinoma occurrence after hepatitis C virus elimination

BACKGROUND

After hepatitis C virus (HCV) elimination, patients should be followed up due to risk of hepatocellular carcinoma (HCC). Growth differentiation factor 15 (GDF15) is a cytokine induced by mitochondrial dysfunction or oxidative stress. Aim To evaluate the prognostic value of GDF15 for HCC occurrence after HCV elimination.

METHODS

We measured GDF15 levels in stored serum from patients with chronic HCV infection without a history of HCC who had achieved sustained virological response with direct-acting antiviral agents (DAAs). The patients were randomly divided into derivation (n = 964) and validation (n = 642) cohorts.

RESULTS

In the derivation cohort, serum GDF15 levels were higher in those with HCC occurrence after DAA treatment than in those without. Multivariate Cox proportional hazards analysis revealed baseline GDF15 (>1350 pg/mL, HR 2.54), AFP (>5 ng/mL, HR 2.00), and the FIB-4 index (>3.25, HR 2.69) to be independent risk factors for HCC. Scoring based on GDF15, AFP and the FIB-4 index stratified HCC occurrence risk. In the validation cohort, the cumulative HCC occurrence rate at 3 years was 0.64%, 3.27% and 15.3% in low-score (N = 171), medium-score (N = 300) and high-score (N = 166) groups, respectively. In the total cohort, scoring divided patients with a FIB-4 index ≤3.25, whose HCC occurrence rate was 2.0% at 3 years, into medium-score and low-score groups with HCC occurrence rates at 3 years of 3.76% and 0.24%, respectively.

CONCLUSIONS

Serum GDF15 predicts de novo HCC occurrence. Scoring using GDF15, AFP, and the FIB-4 index can predict de novo HCC occurrence risk after HCV elimination.

Osmium Complex-Chromophore Conjugates with Both Singlet-to-Triplet Absorption and Long Triplet Lifetime through Tuning of the Heavy-Atom Effect

Os(II) complexes showing singlet-to-triplet absorption are of growing interest as a new class of triplet sensitizers that circumvent energy loss during intersystem crossing, and they enable effective utilization of input photon energy in various applications, such as photoredox catalysis, photodynamic therapy, and photon upconversion. However, triplet excited-state lifetimes of Os(II) complexes are often too short (τ < 1 μs) to transfer their energy to neighboring molecules. While the covalent conjugation of chromophores has been known to extend the net excited-state lifetimes through an intramolecular triplet energy transfer (IMET), heavy-atom effects of the central metals on the attached chromophore units have rarely been discussed. Here, we investigate the relationship between the spin-density contribution of the heavy metals and the net triplet excited-state lifetimes for a series of Os(II) and Ru(II) bis(terpyridine) complexes modified with perylene units. Phosphorescence lifetimes of these compounds strongly depend on the lifetimes of the perylenyl group-localized excited states that are shortened by the heavy-atom effect. The degree of heavy-atom effect can be largely circumvented by introducing meta-phenylene bridges, where the perylene unit retains its intrinsic long excited-state lifetime. The thermal activation to the short-lived excited states is suppressed, thanks to sufficient but still small energy losses during the IMET process. Involvement of the metal center was also confirmed by the prolonged lifetime by replacing Os(II) with Ru(II) that possesses a smaller spin-orbit coupling constant. These results indicate the importance of ligand structures that give a minimum heavy-atom effect as well as the sufficient energy gap among the excited states and fast IMET for elongating the triplet excited-state lifetime without sacrificing the excitation energy.

Spin Statistics for Triplet-Triplet Annihilation Upconversion: Exchange Coupling, Intermolecular Orientation, and Reverse Intersystem Crossing

Triplet-triplet annihilation upconversion (TTA-UC) has great potential to significantly improve the light harvesting capabilities of photovoltaic cells and is also sought after for biomedical applications. Many factors combine to influence the overall efficiency of TTA-UC, the most fundamental of which is the spin statistical factor, η, that gives the probability that a bright singlet state is formed from a pair of annihilating triplet states. The value of η is also critical in determining the contribution of TTA to the overall efficiency of organic light-emitting diodes. Using solid rubrene as a model system, we reiterate why experimentally measured magnetic field effects prove that annihilating triplets first form weakly exchange-coupled triplet-pair states. This is contrary to conventional discussions of TTA-UC that implicitly assume strong exchange coupling, and we show that it has profound implications for the spin statistical factor η. For example, variations in intermolecular orientation tune η from to through spin mixing of the triplet-pair wave functions. Because the fate of spin-1 triplet-pair states is particularly crucial in determining η, we investigate it in rubrene using pump-push-probe spectroscopy and find additional evidence for the recently reported high-level reverse intersystem crossing channel. We incorporate all of these factors into an updated model framework with which to understand the spin statistics of TTA-UC and use it to rationalize the differences in reported values of η among different common annihilator systems. We suggest that harnessing high-level reverse intersystem crossing channels in new annihilator molecules may be a highly promising strategy to exceed any spin statistical limit.

Determination of physiological cardiac myosin-binging protein levels (cMyc) in healthy populations

Background

Cardiac myosin–binding protein C (cMyC) is a cardiac-restricted protein that has more abundant, rapid release and clearance kinetics than cardiac troponin. The current ESC guideline suggests the cMyC may provide value as an alternative to cardiac troponin. The 99th percentile value is universally endorsed as the reference cut off to aid in the diagnosis of acute myocardial infarction (AMI), however, none of the report of healthy population of cMyC.

Purpose

The aim of this study was to evaluate the distribution of cMyC values in healthy subjects.

Methods

We used two cohorts in this retrospective study. 1) Healthy subjects; a total of 500 subjects (250 men and 250 women) who had annual health examinations in 2012 in the area of Kamigoto, a suburb of Nagasaki city in Southern Japan were enrolled. All participants showed none of abnormal findings including cell blood counts, chemical analysis, liver function tests, general urine tests, occult blood tests of stool, barium swallow, mammography for women, abdominal ultrasound sonography, and electrocardiogram. All blood samples were obtained in a fasting state in the morning. 2) Chest pain subjects; we collected samples from 250 subjects including 50 with non-ST elevation myocardial infarction visited admitted to a university hospital for measurement of high-sensitivity troponin T and coronary artery assessment by coronary angiography. We measured cMyC level in both cohorts by HISCL™-800 system (Sysmex corporation, Japan). The assay has a limit of detection of 0.5 ng/L and a lower limit of quantification of 1.3 ng/L.

Result

In healthy subjects, median age (IQR) was 44 (20, 82) in men and 50 (23, 91) in women. The 99th percentile of cMyC was 27.3 ng/L, which was around one-third lower than that in previous report (87 ng/L). In chest pain subjects, the concentrations of cMyC at presentation were significantly higher in those with versus without AMI (median, 66 ng/L versus 10 ng/L, P&lt;0.001). Discriminatory power for AMI, as quantified by the area under the receiver-operating characteristic curve (AUC), was comparable for cMyC (AUC, 0.85 (95% CI 0.79–0.91) and hs-cTnT (AUC, 0.81 (95% CI 0.76–0.88)).

Conclusion

We defined the normal range of cMyC in healthy Japanese subjects. The level of cMyC at presentation provides discriminatory power comparable to hs-cTnT in the diagnosis of AMI. To determine the physiological value of a biomarker may be necessary to evaluate enough information about their health status.

Funding Acknowledgement

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

Left atrial dysfunction still exists in patients who obtain normal left atrial volume after successful ablation of atrial fibrillation

Introduction

Atrial fibrillation (AF) promotes left atrial (LA) remodeling and vice versa. LA volume index (LAVI) ≥34 mL/m2 is an established cut-off value for identifying an enlarged left atrium. Catheter ablation has become an established therapy for AF and provides a reduction of LA volume by maintaining sinus rhythm (reverse remodeling). However, the definition of LA reverse remodeling after AF ablation is undetermined.

Purpose

We hypothesized that patients with LA dilatation who obtain normal LA volume (LAVI &lt;34 mL/m2) after AF ablation would have better long-term outcomes than those who do not. Furthermore, we investigated whether patients with a normal LA volume could also obtain normal LA function with AF ablation.

Methods

We enrolled 140 AF patients with baseline LAVI ≥34 mL/m2, without AF recurrence for 1 year after the initial AF ablation. We acquired conventional and speckle-tracking echocardiographic parameters within 24 h and at 1 year after the procedure. Late recurrence was defined as AF recurrence &gt;1 year after the initial ablation. To define the normal range of LA function, age-and sex-matched 140 controls without a history of AF were also enrolled.

Results

After restoration of sinus rhythm, overall LA structural and functional parameters were significantly improved, and 75 patients (54%) had normal LA volume at the time of follow-up (Table). During a median follow-up of 44 (31–61) months, 32 patients (23%) experienced a late recurrence of AF. Patients who obtained normal LA volume after AF ablation had fewer late recurrences than those who did not (P&lt;0.01) (Figure). However, LA functional abnormalities still existed in AF patients, even if LA volume was normalized as in controls (Table).

Conclusion

Patients who obtain normal LA volume have better long-term outcomes of AF ablation than those who do not. Although AF ablation promotes beneficial effects on LA structure and function, LA function cannot be normalized even in patients who obtain normal LA volume after successful ablation. Thus, physicians should carefully consider long-term follow-up and residual AF risks, regardless of sinus rhythm restoration by catheter ablation.

Funding Acknowledgement

Type of funding sources: None.

Isolation of Rhodococcus equi from the gastrointestinal contents of earthworms (family Megascolecidae)

Rhodococcus equi was isolated from the gastrointestinal contents of earthworms (family Megascolecidae) and their surrounding soil collected from pastures of two horse-breeding farms in Aomori Prefecture, outdoor pig pens, forest in Towada campus, orange groves and forest where wild boars (Sus scrofa) are established in Tanabe, Wakayama Prefecture. The number of R. equi in the lower gastrointestinal contents of 23 earthworms collected from our campus was significantly larger than that of the upper gastrointestinal content. The mean numbers of R. equi from the gastrointestinal contents of earthworms collected from the various places were 2·3-fold to 39·7-fold more than those of the surrounding soil samples. In all, 1771 isolates from the earthworms and 489 isolates from the soil samples were tested for the presence of vapA and vapB genes using polymerase chain reaction. At the horse-breeding farm N, 9 of the 109 isolates (8·3%) from the earthworms and 7 of the 106 isolates (6·6%) from the soil samples were positive for the vapA gene. At the University's forest, one of the 250 isolates (0·4%) from the gastrointestinal contents of the earthworm was positive for the vapB gene. These results revealed that R. equi can be found in significant quantities in the gastrointestinal contents of earthworms, suggesting that they act as an accumulator of R. equi in the soil environment and as a source or reservoir of animal infection.

Design Guidelines to Elongate Spin-Lattice Relaxation Times of Porphyrins with Large Triplet Electron Polarization

The spin-polarized triplet state generated by light irradiation has potential for applications such as triplet dynamic nuclear polarization (triplet-DNP). Recently, we have reported free-base porphyrins as versatile and biocompatible polarizing agents for triplet-DNP. However, the electron polarization of free-base porphyrins is not very high, and the dilemma is that the high polarization of metalloporphyrins is accompanied by a too short spin-lattice relaxation time to be used for triplet-DNP. We report here that the introduction of electron-withdrawing fluorine groups into Zn porphyrins enables a long enough spin-lattice relaxation time (>1 μs) while maintaining a high polarization (P_x:P_y:P_z = 0:0:1.0) at room temperature. Interestingly, the spin-lattice relaxation time of Zn porphyrin becomes much longer by introducing fluorine substituents, whereas the spin-lattice relaxation time of free-base porphyrin becomes shorter by the fluorine substitution. Theoretical calculations suggest that this is because the introduction of the electron-withdrawing fluorine substituents reduces the spin density on Zn atoms and weakens the spin-orbit interaction.

Relationship between Shear Stiffness Measured by MR Elastography and Perfusion Metrics Measured by Perfusion CT of Meningiomas

BACKGROUND AND PURPOSE

When managing meningiomas, intraoperative tumor consistency and histologic subtype are indispensable factors influencing operative strategy. The purposes of this study were the following: 1) to investigate the correlation between stiffness assessed with MR elastography and perfusion metrics from perfusion CT, 2) to evaluate whether MR elastography and perfusion CT could predict intraoperative tumor consistency, and 3) to explore the predictive value of stiffness and perfusion metrics in distinguishing among histologic subtypes of meningioma.

MATERIALS AND METHODS

Mean tumor stiffness and relative perfusion metrics (blood flow, blood volume, and MTT) were calculated (relative to normal brain tissue) for 14 patients with meningiomas who underwent MR elastography and perfusion CT before surgery (cohort 1). Intraoperative tumor consistency was graded by a neurosurgeon in 18 patients (cohort 2, comprising the 14 patients from cohort 1 plus 4 additional patients). The correlation between tumor stiffness and perfusion metrics was evaluated in cohort 1, as was the ability of perfusion metrics to predict intraoperative tumor consistency and discriminate histologic subtypes. Cohort 2 was analyzed for the ability of stiffness to determine intraoperative tumor consistency and histologic subtypes.

RESULTS

The relative MTT was inversely correlated with stiffness (P = .006). Tumor stiffness was positively correlated with intraoperative tumor consistency (P = .01), while perfusion metrics were not. Relative MTT significantly discriminated transitional meningioma from meningothelial meningioma (P = .04), while stiffness did not significantly differentiate any histologic subtypes.

CONCLUSIONS

In meningioma, tumor stiffness may be useful to predict intraoperative tumor consistency, while relative MTT may potentially correlate with tumor stiffness and differentiate transitional meningioma from meningothelial meningioma.

Hepatic Stellate Cells in Hepatocellular Carcinoma Promote Tumor Growth Via Growth Differentiation Factor 15 Production

BACKGROUND & AIMS

Although the tumor microenvironment plays an important role in tumor growth, it is not fully understood what role hepatic stellate cells (HSCs) play in the hepatocellular carcinoma (HCC) microenvironment.

METHODS

A high-fat diet after streptozotocin was administered to HSC-specific Atg7-deficient (GFAP-Atg7 knockout [KO]) or growth differentiation factor 15 (GDF15)-deficient (GFAP-GDF15KO) mice. LX-2 cells, a human HSC cell line, were cultured with human hepatoma cells.

RESULTS

In the steatohepatitis-based tumorigenesis model, GFAP-Atg7KO mice formed fewer and smaller liver tumors than their wild-type littermates. Mixed culture of LX-2 cells and hepatoma cells promoted LX-2 cell autophagy and hepatoma cell proliferation, which were attenuated by Atg7 KO in LX-2 cells. Hepatoma cell xenograft tumors grew rapidly in the presence of LX-2 cells, but Atg7 KO in LX-2 cells abolished this growth. RNA-sequencing revealed that LX-2 cells cultured with HepG2 cells highly expressed GDF15, which was abolished by Atg7 KO in LX-2 cells. GDF15 KO LX-2 cells did not show a growth-promoting effect on hepatoma cells either in vitro or in the xenograft model. GDF15 deficiency in HSCs reduced liver tumor size caused by the steatohepatitis-based tumorigenesis model. GDF15 was highly expressed and GDF15-positive nonparenchymal cells were more abundant in human HCC compared with noncancerous parts. Single-cell RNA sequencing showed that GDF15-positive rates in HSCs were higher in HCC than in background liver. Serum GDF15 levels were high in HCC patients and increased with tumor progression.

CONCLUSIONS

In the HCC microenvironment, an increase of HSCs that produces GDF15 in an autophagy-dependent manner may be involved in tumor progression.

Impact of right ventricular contractile reserve on exercise capacity in patients with heart failure: clinical application of low-load exercise stress echocardiography

Background

The peak oxygen uptake (VO2) evaluated by the cardiopulmonary exercise test (CPX) is an established marker of exercise capacity in patients with heart failure (HF). In particular, peak VO2 &lt;14 ml/kg/min is used to be one of the criteria for heart transplantation. However, given exercise intolerance in patients with HF, it is difficult for refractory HF patients to reach sufficient exercise load. A recent report has highlighted significant impact of right ventricular (RV) function on mortality and urgent heart transplantation. Taken together, we hypothesized that the assessment of RV function was helpful to predict exercise capacity by using low-load exercise stress echocardiography (low-load ESE) in patients with HF.

Purpose

We evaluated whether RV dysfunction assessed by the low-load ESE determined a low peak VO2 &lt;14 ml/kg/min in patients with HF.

Methods

We studied 67 consecutive hospitalized patients with HF (mean age, 65 years; 75% male; mean LV ejection fraction, 36%) who underwent ESE and CPX after stabilized HF condition, and the time interval of CPX and ESE tests was within 48 hours. CPX was performed using an upright cycle ergometer by a ramp protocol, while ESE was performed using ergometer in semi-supine position and the workload was generally increased by 25 watts every 3 minutes. The low-load ESE was defined as the 25 watts exercise. The increments of RV s' velocity at tricuspid annulus and RV strain in the free wall were considered as a preservation of RV contractile reserve. Among the study population, 26 patients were performed right heart catheterization and RV dP/dt/Pmax was estimated as an invasive marker of RV contractility.

Results

The achieved intensity of exercise was 50.4±21.0 watts, and all patients completed the low-load ESE. The invasive study showed that the change of RV s' velocity during the low-load ESE significantly correlated with RV dP/dt/Pmax (r=0.706, p&lt;0.001). As shown in Figure, the non-invasive parameters of RV contractile reserve during the low-load ESE were significantly correlated with peak VO2 (RV s' velocity: r=0.787, p&lt;0.001; RV strain: r=0.244, p=0.047). ROC analysis showed that the change of RV s' velocity during the low-load ESE correctly identified patients with peak VO2 &lt;14 ml/kg/min (AUC=0.95, sensitivity 92.3%, specificity 85.2%). In terms of inter- and intra-observer variabilities, ICCs of the change of RV s' velocity were 0.86 and 0.96, and ICCs of the changes of RV strain were 0.63 and 0.70, respectively.

Conclusion

The change of RV s' velocity during the low-load ESE could determine exercise tolerance in patients with HF. The assessment of RV contractile reserve might be clinically useful to discriminate high risk HF patients.

Figure 1

Funding Acknowledgement

Type of funding source: None

Biodegradable-polymer versus durable-polymer drug eluting stents for coronary artery disease: systematic review and a meta-analysis

Background

Biodegradable polymer drug-eluting stents (BP-DES) has been developed to overcome the potential drawbacks of the first-generation durable polymer drug-eluting stents (DP-DES). However, it is still under debate whether BP-DES is associated with superior efficacy and safety over DP-DES.

Purpose

We sought to compare the effects of BP-DES and DP-DES in patients with coronary artery disease.

Methods

We performed systematic review and a meta-analysis of randomized controlled trials comparing BP-DES and DP-DES on clinical outcomes in patients with coronary artery disease using CE-mark approved drug-eluting stents (DES) with at least 1-year follow-up. We included 32 studies involving 39,686 patients (BP-DES: 21,439 patients, and DP-DES: 18,247 patients). Primary outcome measure was target vessel failure (TVF; equivalent to the composite of cardiac death, target-vessel myocardial infarction, or ischemia-driven target vessel revascularization). We performed subgroup analysis according to the DP-DES generations (newer-generation DP-DES: 15,179patients, and first-generation DP-DES: 3,068 patients), and the effects of newer-generation DP-DES was compared with the BP-DES according to the BP-DES strut thickness (Ultra-thin strut [&lt;80μm]: 7,572 patients, Thin-strut [80–100μm]: 5,465 patients, and Thick-strut [≥80μm]: 5,876 patients).

Results

The odds for TVF was not significantly different between the BP-DES group and the DP-DES group in the entire study population (odds ratio [OR] 0.96, 95% confidence interval [CI] [0.90–1.02], P=0.20). The odds for TVF was significantly low in the BP-DES group relative to the first-generation DP-DES group, however the odds were comparable between the BP-DES group and the newer-generation DP-DES group (BP-DES versus first-generation DP-DES: OR 0.82, 95% CI [0.73–0.92], P&lt;0.001, and BP-DES versus newer-generation DP-DES: OR 1.00, 95% CI [0.93–1.08], P=0.99). We also found no significant differences between the BP-DES and newer-generation DP-DES, in all subgroups stratified by the BP-DES strut thickness (Ultra-thin strut BP-DES versus newer-generation DP-DES: OR 0.88, 95% CI [0.76–1.02], P=0.10, Thin-strut BP-DES versus newer-generation DP-DES: OR 1.01, 95% CI [0.90–1.13], P=0.89, and Thick strut BP-DES versus newer-generation DP-DES: OR 1.11, 95% CI [0.99–1.25], P=0.08).

Conclusions

In this meta-analysis of randomized controlled trials evaluating clinical outcomes, there was no significant differences between BP-DES and DP-DES. We found beneficial effects of BP-DES relative to the first-generation DP-DES, however, there was no statistical differences between BP-DES and newer-generation DP-DES, irrespective of the BP-DES strut thickness.

Pooled odds ratios for clinical outcomes

Funding Acknowledgement

Type of funding source: None

The impact of catheter ablation for patients with asymptomatic atrial fibrillation: subanalysis of kansai plus atrial fibrillation (kpaf) registry

Background

Catheter ablation (CA) of atrial fibrillation (AF) for symptomatic patients improves the quality of life and prognosis of patients with heart failure. However, the impact of CA for asymptomatic patients is still controversial.

Purpose

We aimed to investigate the clinical outcomes of CA of AF for asymptomatic patients compared to those for symptomatic patients.

Methods

A total of 5,013 patients from the Kansai Plus Atrial Fibrillation (KPAF) Registry who underwent CA were screened. The patients were divided into three groups by type of AF; paroxysmal (PAF), persistent (PEAF) and long standing (LSAF) and the patients in each type of AF were divided into two groups: asymptomatic and symptomatic. The primary endpoint was recurrent supraventricular tachyarrhythmias lasting for more than 30 seconds during follow-up 4 years after CA. The secondary endpoint was a composite of cardiovascular, cerebral, and gastrointestinal events during follow-up 4 years after CA. The incidence of complications related to CA between asymptomatic and symptomatic patients was also evaluated. Kaplan–Meier analysis was employed to estimate the primary and secondary endpoints. The statistical differences in primary and secondary endpoints between asymptomatic and symptomatic patients were evaluated using a log–rank test. The impact of symptom due to AF on the primary and secondary endpoint was evaluated using a Cox hazard analysis. The difference in incidence of complications between asymptomatic and symptomatic patients was evaluated using a chi–square test.

Results

In this study population, PAF was the most frequent at 64.4%, followed by PEAF (22.7%) and LSAF (13.0%). There were some significant differences in the baseline characteristics between asymptomatic and symptomatic patients in each type of AF. The proportion of male was significantly higher in asymptomatic patients than symptomatic patients in PAF (81.2% versus 67.2%, p&lt;0.001) and PEAF (86.4% versus 74.3%, p&lt;0.001). Left atrial diameter was larger in asymptomatic patients than symptomatic patients only in PAF (40±6mm versus 38±6mm, p&lt;0.001). In all types of AF, there was no significant difference in primary endpoint between asymptomatic and symptomatic patients as follows: 37.5% versus 40.6% (p=0.6) in PAF, 45.2% versus 55.1% (p=0.09) in PEAF and 59.3% versus 63.6% (p=1.0) in LSAF. There was also no significant difference in secondary endpoint between asymptomatic and symptomatic patients: 7.1% versus 6.8% (p=0.7) in PAF, 5.4% versus 8.7% (p=0.3) in PEAF and 4.4% versus 5.1% (p=0.5) in LSAF. In a Cox hazard analysis, the symptom did not affect both of the primary and secondary endpoints in each type of AF. In regard to the incidence of complications related to CA, there was no significant difference between asymptomatic and symptomatic patients in each type of AF.

Conclusion

CA of AF for asymptomatic patients can be safe and can lead to equivalent outcomes as well as symptomatic patients.

Funding Acknowledgement

Type of funding source: None

Reinvestigation of the virulence of Rhodococcus equi isolates from patients with and without AIDS

Rhodococcus equi emerged as a zoonotic pathogen of human immunodeficiency virus-infected patients over the last three decades. Two virulence plasmid types of R. equi, pVAPA and pVAPB associated with equine and porcine isolates, have been recognized, and more recently, pVAPN, a novel host-associated virulence plasmid in R. equi, was found in bovine and caprine isolates. We reinvestigated 39 previously reported isolates of R. equi from patients with and without acquired immunodeficiency syndrome (AIDS) by detecting vapA, vapB and vapN using PCR and plasmid profiling. After excluding one isolate that could not be cultured from frozen storage, eight isolates carried a virulence plasmid encoding vapA (pVAPA), 10 carried a virulence plasmid encoding vapB (pVAPB), seven carried a virulence plasmid encoding vapN (pVAPN) and 13 were negative for those genes. Of the 29 isolates from patients with AIDS, 7, 10 and 5 harboured pVAPA, pVAPB and pVAPN respectively. Among nine isolates from patients without AIDS, one and two harboured pVAPA and pVAPN respectively. This study demonstrated that pVAPN-positive R. equi existed in human isolates before 1994 and reaffirmed that equine-associated pVAPA-positive, porcine-associated pVAPB-positive and bovine- or caprine-associated pVAPN-positive R. equi are widely spread globally. Because domestic animals might be major sources of human infection, further research is needed to reveal the prevalence of pVAPN-positive R. equi infection in cattle and goats.

Multielectron-Ion Coincidence Spectroscopy of Xe in Extreme Ultraviolet Laser Fields: Nonlinear Multiple Ionization via Double Core-Hole States

Ultrafast multiphoton ionization of Xe in strong extreme ultraviolet free-electron laser (FEL) fields (91 eV, 30 fs, 1.6×10^{12}  W/cm^{2}) has been investigated by multielectron-ion coincidence spectroscopy. The electron spectra recorded in coincidence with Xe^{4+} show characteristic features associated with two-photon absorption to the 4d^{-2} double core-hole (DCH) states and subsequent Auger decay. It is found that the pathway via the DCH states, which has eluded clear identification in previous studies, makes a large contribution to the multiple ionization, despite the long FEL pulse duration compared with the lifetime of the 4d core-hole states.

Leaping across the visible range: near-infrared-to-violet photon upconversion employing a silyl-substituted anthracene

The first example of near-infrared (NIR, λ > 700 nm)-to-violet (λ < 450 nm) photon upconversion based on triplet–triplet annihilation is achieved by developing a silyl-substituted anthracene violet emitter with a low triplet energy level.

Cotreatment with lenvatinib and warfarin potassium caused prothrombin time prolongation

Lenvatinib is approved as a standard systemic therapy for unresectable hepatocellular carcinoma (HCC) patients; however, experience with lenvatinib in clinical practice is insufficient. We present the case of a patient with advanced HCC whose prothrombin time - international normalized ratio (PT-INR) was elevated after cotreatment with lenvatinib and warfarin potassium. The patient was a 26-year-old man with congenital abnormalities who had to take warfarin potassium because he had a mechanical heart valve. He was diagnosed with unresectable HCC at 24 years old and was treated by transcatheter arterial chemoembolization and transcatheter arterial infusion. After some interventional radiology treatments, lenvatinib was started. After 4 days of treatment with lenvatinib and warfarin potassium, his PT-INR increased to 4.13, and the treatment had to be stopped. No changes were observed in other Child-Pugh score factors. The elevation in the PT-INR after cotreatment with lenvatinib and warfarin potassium was thought to be caused by pharmacological effects of concurrent use or pharmacological sensitivity to warfarin potassium in this patient with liver dysfunction. The PT-INR must be monitored when lenvatinib is given to advanced HCC patients taking warfarin potassium.

Near-Infrared Optogenetic Genome Engineering Based on Photon-Upconversion Hydrogels

Photon upconversion (UC) from near-infrared (NIR) light to visible light has enabled optogenetic manipulations in deep tissues. However, materials for NIR optogenetics have been limited to inorganic UC nanoparticles. Herein, NIR-light-triggered optogenetics using biocompatible, organic TTA-UC hydrogels is reported. To achieve triplet sensitization even in highly viscous hydrogel matrices, a NIR-absorbing complex is covalently linked with energy-pooling acceptor chromophores, which significantly elongates the donor triplet lifetime. The donor and acceptor are solubilized in hydrogels formed from biocompatible Pluronic F127 micelles, and heat treatment endows the excited triplets in the hydrogel with remarkable oxygen tolerance. Combined with photoactivatable Cre recombinase technology, NIR-light stimulation successfully performs genome engineering resulting in the formation of dendritic-spine-like structures of hippocampal neurons.

Prophylactic effect of rikkunshito, an herbal medicine, for chemotherapy-induced nausea in thoracic cancer patients receiving carboplatin-based chemotherapy

Rikkunshito has been shown to improve upper gastrointestinal symptoms and anorexia. The aim of this study was to evaluate whether rikkunshito improves chemotherapy-induced nausea in thoracic cancer patients receiving carboplatin (CBDCA)-based chemotherapy. A retrospective before-and-after comparison study was conducted in patients with thoracic cancer receiving the first cycle of CBDCA-based chemotherapy. Among 61 eligible patients, 34 received standard antiemetic therapy with a combination of 5-hydroxytryptamine-3 receptor antagonist and dexamethasone from September 2012 and June 2013 (standard group), while the other 27 received the standard antiemetic therapy plus oral rikkunshito from July 2013 and December 2014 (rikkunshito group). The rates of no nausea showed no significant difference between the standard and rikkunshito group (Overall phase: 64.7 % for standard group vs 74.1 % for rikkunshito group, p = 0.579). Subgroup analysis indicated that, in female patients, the rates of no nausea in rikkunshito groups was significantly higher than in standard group (overall phase: 44.4 % vs 100 %, p = 0.034). Rikkunshito did not demonstrate an additional prophylactic effect on standard antiemetic therapy for nausea in patients with thoracic cancer receiving CBDCA-based chemotherapy, but showed a prophylactic effect of nausea in female patients.

Upconverting Oil-Laden Hollow Mesoporous Silica Microcapsules for Anti-Stokes-Based Biophotonic Applications

A recyclable, aqueous phase functioning and biocompatible photon upconverting system is developed. Hollow mesoporous silica microcapsules (HMSMs) with ordered radial mesochannels were employed, for the first time, as vehicles for the post-encapsulation of oil phase triplet-triplet annihilation upconversion (TTA-UC), with the capability of homogeneous suspension in water. In-depth characterization of such upconverting oil-laden HMSMs (UC-HMSMs) showed that the mesoporous silica shells reversibly stabilized the encapsulated UC oil in water to allow efficient upconverted emission, even under aerated conditions. In addition, the UC-HMSMs were found to actively bind to the surface of human mesenchymal stem cells without significant cytotoxicity and displayed upconverted bright blue emission under 640 nm excitation, indicating a potential of our new TTA-UC system in biophotonic applications. These findings reveal the great promise of UC-HMSMs to serve as ideal vehicles not only for ultralow-power in vivo imaging but also for stem cell labeling, to facilitate the tracking of tumor cells in animal models.

Basic evaluation of a novel 4D target and human body phantom

Stereotactic body radiation therapy (SBRT) is usually verified with a dynamic phantom or solid phantom, but there is a demand for phantoms that can accurately simulate tumor dynamics within an individual that would allow customized validation in every patient. We developed a new 4D dynamic target phantom (multi-cell 4D phantom) that allows simulation of tumor movement in patients. The basic quality and dynamic reproducibility of this new phantom was verified in this investigation. The newly developed multi-cell 4D phantom comprises four main components: soft tissue, bones, lungs, and tumor (target). The phantom structure was based on computed tomography (CT) data of a male. In this study, we investigated the basic performance of a multi-cell 4D phantom. All the CT numbers of the phantom were very close to those of human data. The geometric maximum amplitudes were 4.57 mm in the lateral direction, 4.59 mm in the ventrodorsal direction, and 3.68 mm in the cranio-caudal direction. Geometric errors were 0.84, 0.58, and 0.40 mm, respectively. Movements of the abdominal surface were stable for 60 s. Repeated measurements show no actual differences in target movements between multiple measurements and indicated high reproducibility (r  >  0.97). End-to-end tests using Gafchromic film revealed a gamma pass rate of 98% or above (2 mm/3%). Although our phantom performed limited reproducibility in the movement of the patient tumor at present, a satisfactory level of precision was confirmed in general. This is a very promising device for use in the verification of radiation therapy for moving targets.