Translational insights and overall survival in the U31402-A-U102 study of patritumab deruxtecan (HER3-DXd) in EGFR-mutated NSCLC

BACKGROUND

Human epidermal growth factor receptor 3 (HER3) is broadly expressed in non-small-cell lung cancer (NSCLC) and is the target of patritumab deruxtecan (HER3-DXd), an antibody-drug conjugate consisting of a HER3 antibody attached to a topoisomerase I inhibitor payload via a tetrapeptide-based cleavable linker. U31402-A-U102 is an ongoing phase I study of HER3-DXd in patients with advanced NSCLC. Patients with epidermal growth factor receptor (EGFR)-mutated NSCLC that progressed after EGFR tyrosine kinase inhibitor (TKI) and platinum-based chemotherapy (PBC) who received HER3-DXd 5.6 mg/kg intravenously once every 3 weeks had a confirmed objective response rate (cORR) of 39%. We present median overall survival (OS) with extended follow-up in a larger population of patients with EGFR-mutated NSCLC and an exploratory analysis in those with acquired genomic alterations potentially associated with resistance to HER3-DXd.

PATIENTS AND METHODS

Safety was assessed in patients with EGFR-mutated NSCLC previously treated with EGFR TKI who received HER3-DXd 5.6 mg/kg; efficacy was assessed in those who also had prior PBC.

RESULTS

In the safety population (N = 102), median treatment duration was 5.5 (range 0.7-27.5) months. Grade ≥3 adverse events occurred in 76.5% of patients; the overall safety profile was consistent with previous reports. In 78/102 patients who had prior third-generation EGFR TKI and PBC, cORR by blinded independent central review (as per RECIST v1.1) was 41.0% [95% confidence interval (CI) 30.0% to 52.7%], median progression-free survival was 6.4 (95% CI 4.4-10.8) months, and median OS was 16.2 (95% CI 11.2-21.9) months. Patients had diverse mechanisms of EGFR TKI resistance at baseline. At tumor progression, acquired mutations in ERBB3 and TOP1 that might confer resistance to HER3-DXd were identified.

CONCLUSIONS

In patients with EGFR-mutated NSCLC after EGFR TKI and PBC, HER3-DXd treatment was associated with a clinically meaningful OS. The tumor biomarker characterization comprised the first description of potential mechanisms of resistance to HER3-DXd therapy.

Temporal and fertilizer-dependent dynamics of soil bacterial communities in buckwheat fields under long-term management

This study integrated bacterial community and soil chemicals to characterize the soil ecosystem in an open upland field managed by six controlled fertilizer programs using the minimum amount of pesticides. Amplicon sequencing the 16S rRNA gene revealed that inorganic nitrogen fertilizer and compost altered the diversity and structure of the soil bacterial community throughout buckwheat (Fagopyrum esculentum Moench 'Hitachiakisoba') cultivation. The bacterial community comprised three clusters that contained bacteria that are prevalent in soils fertilized with nitrogen (cluster 1, 340 taxa), without nitrogen and compost (cluster 2, 234 taxa), and with compost-fertilized (cluster 3, 296 taxa). Cluster 2 contained more taxa in Actinobacteriota and less in Acidobacteriota, and cluster 3 contained more taxa in Gemmatimonadota compared with the other clusters. The most frequent taxa in cluster 1 were within the Chloroflexi phylum. The bacterial community structure correlated with soil chemical properties including pH, total organic carbon, SO42-, soluble Ca2+. A co-occurrence network of bacterial taxa and chemicals identified key bacterial groups comprising the center of a community network that determined topology and dynamics of the network. Temporal dynamics of the bacterial community structure indicated that Burkholderiales were associated with buckwheat ripening, indicating plant-bacteria interaction in the ecosystem.

Increase in Paracellular Leakage of Amino Acids Mediated by Aging-Induced Reduction of Claudin-4 Expression

BACKGROUND

Claudins (CLDNs), major components of tight junctions, control paracellular permeabilities of mineral ions and wastes. The absorption of nutrients including glucose and amino acids (AAs) is regulated by intestinal epithelial cells. However, the role of CLDNs is not fully understood.

OBJECTIVES

The purpose of this study was to clarify the effect of AA deprivation on the expression of AA transporters and CLDNs, as well as the role of CLDNs in the regulation of paracellular AA fluxes.

METHODS

The messenger RNA and protein expression of various CLDNs were examined by real-time quantitative polymerase chain reaction and Western blot analyses, respectively. The AA selectivity of CLDNs was estimated using liquid chromatography-tandem mass spectrometry (LC-MS) analysis.

RESULTS

The expression levels of some AA transporters, CLDN4, and CLDN15 were increased by AA deprivation in normal mouse colon-derived MCE301 cells. The expression of AA transporters and CLDN15 in the mouse colon was positively correlated with aging but the expression of CLDN4 was not. The AA deprivation-induced elevation of CLDN4 expression was inhibited by MHY1485, a mammalian target of rapamycin (mTOR) activator. Furthermore, CLDN4 expression was increased by rapamycin, an mTOR inhibitor. mTOR may be involved in the transcriptional activation of CLDN4. The fluxes of AAs from the basal to apical compartments were decreased and increased by CLDN4 overexpression and silencing, respectively. LC-MS analysis showed that the fluxes of all AAs, especially Lys, His, and Arg, were enhanced by CLDN4 silencing.

CONCLUSIONS

CLDN4 is suggested to form a paracellular barrier to AAs, especially alkaline AAs, which is attenuated with aging.

Regulatory mechanisms of glucose absorption in the mouse proximal small intestine during fasting and feeding

Fasting is known to alter the function of various organs and the mechanisms of glucose metabolism, which affect health outcomes and slow aging. However, it remains unclear how fasting and feeding affects glucose absorption function in the small intestine. We studied the effects of the fasting and feeding on glucose-induced short-circuit current (I_sc) in vitro using an Ussing chamber technique. Glucose-induced I_sc by SGLT1 was observed in the ileum, but little or no I_sc was observed in the jejunum in ad libitum-fed mice. However, in mice fasted for 24-48 h, in addition to the ileum, robust glucose-induced I_sc was observed over time in the jejunum. The expression of SGLT1 in the brush border membranes was significantly decreased in the jejunum under fed conditions compared to 48 h fasting, as analyzed by western blotting. Additionally, when mice were fed a 60% high glucose diet for 3 days, the increase in glucose-induced I_sc was observed only in the ileum, and totally suppressed in the jejunum. An increase in Na⁺ permeability between epithelial cells was concomitantly observed in the jejunum of fasted mice. Transepithelial glucose flux was assessed using a non-metabolizable glucose analog, ¹⁴C-methyl α-D-glucopyranoside glucose (MGP). Regardless of whether fed or fasted, no glucose diffusion mechanism was observed. Fasting increased the SGLT1-mediated MGP flux in the jejunum. In conclusion, segment-dependent up- and down-regulation mechanisms during fasting and feeding are important for efficient glucose absorption once the fast is broken. Additionally, these mechanisms may play a crucial role in the small intestine's ability to autoregulate glucose absorption, preventing acute hyperglycemia when large amounts of glucose are ingested.

The effect of claudin-15 deletion on cationic selectivity and transport in paracellular pathways of the cecum and large intestine

The large intestine plays a pivotal role in water and electrolyte balance. Paracellular transport may play a role in ion transport mechanisms in the cecum and large intestine; however, these molecular mechanisms and their physiological roles have not been fully studied. Claudin-15 forms a cation channel in tight junctions in the small intestine, but its role in the cecum and large intestine has not been investigated. This study aimed to explore the physiological role of claudin-15 in the cecum and large intestine using claudin-15 (Cldn15) KO mice. Electrical conductance, short-circuit current, Na⁺ flux, and dilution potential were assessed in isolated tissue preparations mounted in Ussing chambers. The induced short-circuit current of short-chain fatty acids, which are fermentative products in the intestinal tract, was also measured. Compared to wild type mice, the electrical conductance and paracellular Na⁺ flux was decreased in the cecum, but not the middle large intestine, while in both the cecum and the middle large intestine, paracellular Na⁺ permeability was decreased in Cldn15 KO mice. These results suggest that claudin-15 is responsible for Na⁺ permeability in the tight junctions of the cecum and large intestine and decreased Na⁺ permeability in the cecum may cause impaired absorption function.

High-precision plant height measurement by drone with RTK-GNSS and single camera for real-time processing

Conventional crop height measurements performed using aerial drone images require 3D reconstruction results of several aerial images obtained through structure from motion. Therefore, they require extensive computation time and their measurement accuracy is not high; if the 3D reconstruction result fails, several aerial photos must be captured again. To overcome these challenges, this study proposes a high-precision measurement method that uses a drone equipped with a monocular camera and real-time kinematic global navigation satellite system (RTK-GNSS) for real-time processing. This method performs high-precision stereo matching based on long-baseline lengths (approximately 1 m) during the flight by linking the RTK-GNSS and aerial image capture points. As the baseline length of a typical stereo camera is fixed, once the camera is calibrated on the ground, it does not need to be calibrated again during the flight. However, the proposed system requires quick calibration in flight because the baseline length is not fixed. A new calibration method that is based on zero-mean normalized cross-correlation and two stages least square method, is proposed to further improve the accuracy and stereo matching speed. The proposed method was compared with two conventional methods in natural world environments. It was observed that error rates reduced by 62.2% and 69.4%, for flight altitudes between 10 and 20 m respectively. Moreover, a depth resolution of 1.6 mm and reduction of 44.4% and 63.0% in the error rates were achieved at an altitude of 4.1 m, and the execution time was 88 ms for images with a size of 5472 × 3468 pixels, which is sufficiently fast for real-time measurement.

Na+-dependent intestinal glucose absorption mechanisms and its luminal Na+ homeostasis across metamorphosis from tadpoles to frogs

The abrupt morphological changes of the intestine during metamorphosis have been detailed in frogs. The features of intestinal metamorphosis are shortening of the intestine and remodeling of the intestinal epithelium. It is believed that the purpose of the morphological changes of the intestine is adaptation from aquatic herbivorous to carnivorous life. However, little is known about the physiological importance of these morphological changes. To elucidate the functional changes during metamorphosis, we measured luminal Na⁺ concentrations and Na⁺-dependent glucose uptake in tadpoles and adult African clawed frogs, Xenopus laevis. The small intestine was isolated and divided into four segments in length, the luminal contents collected for analysis of ion concentration by ion chromatography. Phlorizin-sensitive glucose-induced short-circuit current (∆I_sc) was measured in intestinal preparations mounted in Ussing chambers. Although dietary sodium intake was extremely low in tadpoles, luminal Na⁺ concentration gradually increased along the proximal to the middle part of the intestine (>70mM), and this Na⁺ concentration was comparable to that of carnivorous adult frogs. The increment of glucose-induced ∆I_sc was observed in tadpole intestine. We also measured the ∆I_sc induced by acetic acid, which is major the short-chain fatty acid produced by the fermentation. The expression levels of mRNA for Na⁺-dependent glucose transporter 1 and tight junction protein claudin-15 in each intestinal segment was measured. These results suggest that luminal Na⁺ homeostasis is important and luminal Na⁺ is kept at a high concentration for Na⁺-dependent nutrient absorption mechanisms.

Reconstitution of functional tight junctions with individual claudin subtypes in epithelial cells

The claudin family of membrane proteins is responsible for the backbone structure and function of tight junctions (TJs), which regulate the paracellular permeability of epithelia. It is thought that each claudin subtype has its own unique function and the combination of expressed subtypes determines the permeability property of each epithelium. However, many issues remain unsolved in regard to claudin functions, including the detailed functional differences between claudin subtypes and the effect of the combinations of specific claudin subtypes on the structure and function of TJs. To address these issues, it would be useful to have a way of reconstituting TJs containing only the claudin subtype(s) of interest in epithelial cells. In this study, we attempted to reconstitute TJs of individual claudin subtypes in TJ-deficient MDCK cells, designated as claudin quinKO cells, which were previously established from MDCK II cells by deleting the genes of claudin-1, -2, -3, -4, and -7. Exogenous expression of each of claudin-1, -2, -3, -4, and -7 in claudin quinKO cells resulted in the reconstitution of functional TJs. These TJs did not contain claudin-12 and -16, which are endogenously expressed in claudin quinKO cells. Furthermore, overexpression of neither claudin-12 nor claudin-16 resulted in the reconstitution of TJs, demonstrating the existence of claudin subtypes lacking TJ-forming activity in epithelial cells. Exogenous expression of the channel-forming claudin-2, -10a, -10b, and -15 reconstituted TJs with reported paracellular channel properties, demonstrating that these claudin subtypes form paracellular channels by themselves without interaction with other subtypes. Thus, the reconstitution of TJs in claudin quinKO cells is advantageous for further investigation of claudin functions.Key words: tight junction, claudin, paracellular permeability, epithelial barrier.

Gastric functional monitoring by gastric electrical impedance tomography (gEIT) suit with dual-step fuzzy clustering

Gastric Function has been successfully estimated by gastric electrical impedance tomography (gEIT) Suit with dual-step fuzzy clustering. The gEIT Suit which are made of elastic cloth with dual-planar electrodes and compact data acquisition (DAQ) system measures gastric impedance Z to visualize the gastric conductivity distribution σ. The dual-step fuzzy clustering extracts the clustered gastric conductivity distribution ^kσ, which accurately estimates the gastric function. The gEIT Suit with dual-step fuzzy clustering are applied to eight healthy persons during liquid meal consumption to estimate the gastric function under gastric accommodation phase of 200, 400 and 600 mL based on the gastric emptying phase. As the results, the gEIT Suit successfully estimate the gastric function. By the measured impedance Z, the subjects have a mean temporal impedance [Formula: see text]= - 9.27 [Ohm] and p-value of that [Formula: see text] p(Z) = 0.0013[-]as the t-test result. In the case of gastric conductivity distribution σ, the subjects have a value of spatial mean conductivity distribution ⟨σ⟩ = 0.23[-] and p-value of that ⟨σ⟩ p(σ) = 0.0140[-]. Lastly, in the case gastric volume V, subjects have a gastric volume V = 12.44 [%] and p-value p(V) = 0.0664[-].

Effects of EOS789, a novel pan-phosphate transporter inhibitor, on phosphate metabolism : Comparison with a conventional phosphate binder

BACKGROUND

Inorganic phosphate (Pi) binders are the only pharmacologic treatment approved for hyperphosphatemia. However, Pi binders induce the expression of intestinal Pi transporters and have limited effects on the inhibition of Pi transport. EOS789, a novel pan-Pi transporter inhibitor, reportedly has potent efficacy in treating hyperphosphatemia. We investigated the properties of EOS789 with comparison to a conventional Pi binder.

METHODS

Protein and mRNA expression levels of Pi transporters were measured in intestinal and kidney tissues from male Wistar rats fed diets supplemented with EOS789 or lanthanum carbonate (LC). 32Pi permeability was measured in intestinal tissues from normal rats using a chamber.

RESULTS

Increased protein levels of NaPi-2b, an intestinal Pi transporter, and luminal Pi removal were observed in rats treated with LC but not in rats treated with EOS789. EOS789 but not LC suppressed intestinal protein levels of the Pi transporter Pit-1 and sodium/hydrogen exchanger isoform 3. 32Pi flux experiments using small intestine tissues from rats demonstrated that EOS789 may affect transcellular Pi transport in addition to paracellular Pi transport.

CONCLUSION

EOS789 has differing regulatory effects on Pi metabolism compared to LC. The properties of EOS789 may compensate for the limitations of LC therapy. The combined or selective use of EOS789 and conventional Pi binders may allow tighter control of hyperphosphatemia. J. Med. Invest. 70 : 260-270, February, 2023.

POS1349 IMMUNOGLOBULIN G4-RELATED KIDNEY DISEASE’S PREDISPOSITION TO CHRONIC RENAL DYSFUNCTION, COMPLICATIONS OF MALIGNANCY, AND MORTALITY: A LONG-TERM NATIONWIDE MULTICENTER STUDY IN JAPAN

Background

In immunoglobulin G4-related kidney disease (IgG4-RKD), persistent renal insufficiency may be observed despite the good initial response to glucocorticoids[1, 2]. However, its long-term prognosis in relation to renal function as well as malignancy and mortality has not been well clarified.

Objectives

To clarify the long-term renal prognosis, complications of malignancy, mortality, and factors related to those outcomes in IgG4-RKD.

Methods

We retrospectively reviewed the medical records of patients with IgG4-RKD diagnosed by the expert members of the IgG4-RKD working group in the Japanese Society of Nephrology. We investigated clinical, radiological, and histopathological features at baseline and course of renal function, complications of malignancy, and mortality during the long-term observation periods (median 71 months) in 75 patients. Using collected data, we calculated the crude incidence rates (IR) of chronic kidney disease (CKD) status, malignancy, and death. Cox regression analyses were performed to assess CKD-related factors. Additionally, we calculated the standardized incidence ratio (SIR) of malignancy and standardized mortality ratio (SMR) using national Japan statistics.

Results

Fifty-nine patients were male, and 16 were female (median age 70 years). At diagnosis, their median eGFR was 45.1 mL/min/1.73m2 (interquartile range [IQR] 28.6-69.9). Seventy-two patients (96%) were treated with prednisolone at a median initial dose of 30 (IQR 30-39) mg/day, leading to a reasonable initial improvement of renal function. The IR of CKD was 30.2/100 person-years, and 66.7% (50/75) of the patients showed CKD at the last visit. Age- and sex-adjusted Cox regression analyses indicated that lower eGFR (per 10 mL/min/1.73m2, hazard ratio [HR] 0.70, 95% confidence interval [CI] 0.61-0.80), pre-existing hypertension (HR 2.39, 95% CI 1.32-4.34), and wider areas with inflammation (>50% vs. <10%, HR 2.55, 95% CI 1.07-6.08) or fibrosis (>50% vs. <5%, HR 2.84, 95% CI 1.18-6.85) in the biopsied renal specimens at treatment initiation had a significant impact on the time to CKD. Eight patients (10.7%) died during follow-up due to malignancy, severe infection, cerebral hemorrhage, or myocardial infarction. The crude mortality rate was 1.76/100 person-years, and a SMR calculated according to national Japan statistics was 0.97 (95% CI 0.42-1.90). On the other hand, 15 patients were diagnosed as having malignancies during follow-up. The IR of malignancy was 3.71/100 person-years, and the SIR of malignancy was 1.80 (95% CI 1.03-2.93).

Conclusion

This study suggests that pre-treated renal insufficiency and extensive renal inflammatory and fibrotic lesions are related to CKD under glucocorticoid therapy in IgG4-RKD. Similarly with the whole IgG4-related disease, IgG4-RKD may have an increased incidence of malignancy but a mortality rate equivalent to the age- and sex-matched Japanese population.

References

[1]Saeki T et al. The clinical course of patients with IgG4-related kidney disease. Kidney Int. 2013 Oct;84(4):826-33.

[2]Mizushima I et al. Factors related to renal cortical atrophy development after glucocorticoid therapy in IgG4-related kidney disease: a retrospective multicenter study. Arthritis Res Ther. 2016 Nov 25;18(1):273.

Disclosure of Interests

None declared

Expression of Vincristin-induced Peripheral Neuropathy Related to Different Administration Methods

Vincristine (VCR) is an important drug used in R-CHOP regimens for the treatment of non-Hodgkin's lymphoma. The purpose of this study was to examine whether the administration method affects the incidence of VCR-induced peripheral neuropathy. We investigated the ratio of VCR-induced peripheral neuropathy during rapid intravenous infusion and intravenous drip infusion. A total of 71 patients who had received six or more courses of R-CHOP from January, 2015 to December, 2016 at Komaki City Hospital and Ogaki Municipal Hospital were retrospectively investigated. Peripheral neuropathy was observed in 27/39 patients (69 %) and 24/32 (75 %) in rapid intravenous infusion and intravenous drip infusion of VCR, respectively (P = 0.79). Peripheral neuropathy was observed at a high frequency in this study. Additionally, there was no difference in frequency of peripheral neuropathy due to the difference in administration method. In both groups, the degree of peripheral neuropathy was grade 1 and grade 2 in most patients. However, in rapid intravenous infusion, grade 3 peripheral neuropathy was observed. Some cases required dose reduction and discontinuation in rapid intravenous infusion. In contrast, there were no discontinuing patients in the intravenous drip infusion. Therefore, it was suggested that intravenous drip infusion of VCR reduced serious peripheral neuropathy because the ratio requiring dose reduction and discontinuation was less than that in the rapid group. In conclusion, this study is informative as there are few reports focusing on the administration method of vincristine.

Correlation between magnesium pre-loading and cisplatin-induced nephrotoxicity in 5-fluorouracil/cisplatin combination therapy for esophageal cancer

The use of cisplatin may cause nephrotoxicity in patients. Hydration solutions supplemented with magnesium could reduce cisplatin-induced nephrotoxicity. In this study, we evaluated the preventive effect of magnesium pre-loading on cisplatin-induced nephrotoxicity in patients with esophageal cancer. We retrospectively evaluated the prevalence of, and risk factors for, nephrotoxicity in 160 patients with esophageal cancer treated with the 5-fluorouracil/cisplatin regimen from 2014 to 2016 with and without magnesium supplementation. Significant differences were observed between the magnesium and non-magnesium groups in terms of frequency of estimated creatinine clearance of grade 2 or higher that was at 4% (n = 3) and 13% (n = 10) (p = 0.027), respectively. The logistic regression analysis revealed that eCcr of grade 2 or higher was significantly associated with the non-magnesium regimen (odds ratio (OR), 4.175; 95% confidence interval (CI) = 1.061-16.430; p = 0.041) and age ≥ 65 years (OR, 13.951; 95% CI = 1.723-112.974; p = 0.014). This study suggests that 20 mEq magnesium pre-loading significantly reduces the prevalence of cisplatin-induced nephrotoxicity. Furthermore, when cisplatin is administered to individuals older than 64 years, a close observation for the onset of cisplatin-induced nephrotoxicity is crucial.

Open-label phase II study of the efficacy of nivolumab for cancer of unknown primary

BACKGROUND

Cancer of unknown primary (CUP) has a poor prognosis. Given the recent approval of immune checkpoint inhibitors for several cancer types, we carried out a multicenter phase II study to assess the efficacy of nivolumab for patients with CUP.

PATIENTS AND METHODS

Patients with CUP who were previously treated with at least one line of systemic chemotherapy constituted the principal study population. Previously untreated patients with CUP were also enrolled for exploratory analysis. Nivolumab (240 mg/body) was administered every 2 weeks for up to 52 cycles. The primary endpoint was objective response rate in previously treated patients as determined by blinded independent central review according to RECIST version 1.1.

RESULTS

Fifty-six patients with CUP were enrolled in the trial. For the 45 previously treated patients, objective response rate was 22.2% [95% confidence interval (CI), 11.2% to 37.1%], with a median progression-free survival and overall survival of 4.0 months (95% CI, 1.9-5.8 months) and 15.9 months (95% CI, 8.4-21.5 months), respectively. Similar clinical benefits were also observed in the 11 previously untreated patients. Better clinical efficacy of nivolumab was apparent for tumors with a higher programmed death-ligand 1 expression level, for those with a higher tumor mutation burden, and for microsatellite instability-high tumors. In contrast, no differences in efficacy were apparent between tumor subgroups based on estimated tissue of origin. Adverse events were consistent with the known safety profile of nivolumab. No treatment-related death was observed.

CONCLUSIONS

Our results demonstrate a clinical benefit of nivolumab for patients with CUP, suggesting that nivolumab is a potential additional therapeutic option for CUP.

Predictive value of QRS duration normalized to left ventricular volume for responding to cardiac resynchronization therapy in patients with mid-QRS duration enrolled in the multicenter registry

Background

For cardiac resynchronization therapy (CRT), patients with chronic heart failure (HF) and wide (&gt;150msec) QRS duration (QRSd) received class I/A indication. However, its beneficial effect seemed to be limited for those with mid- (120–150msec) QRSd. Recent studies demonstrated that QRSd normalized to left ventricular end-diastolic volume (QRSd/ LVEDV) improved prediction of clinical outcome in patients with CRT. Therefore, we sought to investigate predictive value of QRSd/LVEDV for responding to CRT in patients with mid-QRSd.

Methods

This was retrospective multi-center observational cohort study. A total 506 consecutive patients who underwent CRT implantation in Tohoku University Hospital and National Cerebral and Cardiovascular Center were evaluated. Exclusion criteria were QRSd less than 120ms, upgrade procedures from other implanted non-CRT devices and bradycardia requiring pacing. We evaluated clinical variables, data of electrocardiogram and transthoracic echocardiography at baseline and 6 months after CRT implantation. Primary endpoint was a HF hospitalization after CRT implantation. Distribution of free from HF hospitalization during follow-up was calculated using Kaplan-Meier curves, and the effects of covariate on the time to endpoint were investigated using a Cox proportional hazards model.

Results

After 199 patients were excluded based on exclusion criterion, remaining 307 patients were included for the analysis. Mean age was 62±14 [SD] years, and 238 (77%) were male. Mean LVEF and LVEDV were 25±9% and 234±82ml, respectively, and 24% of patients had ischemic etiology of HF. During the median 948 days of follow-up, CRT patients with mid QRSd (n=126; 136±10msec), as compared with those with wide QRSd (n=181; 174±17msec), tended to have higher incidence of HF hospitalization (Wilcoxon p=0.03). Multivariate analysis showed that QRSd and QRSd/LVEDV were significant predictors for HF hospitalization in CRT patients with mid QRSd, and cut-off values (137msec of QRSd and 0.65 of QRSd/LVEDV), which was calculated by receiver operative curve analysis, was used for risk stratification. QRSd&lt;137msec was significant negative predictors for HF hospitalization (p=0.005), and Mid-QRSd patients with QRSd≥137msec demonstrated equivalent clinical outcome with those with wide QRSd. Moreover, patients with QRSd/LVEDV≥0.65 tended to have lower incidence of HF hospitalization as compared with those without it among patients with QRSd&lt;137msec (n=64, Figure).

Conclusion

The present study demonstrates that QRSd normalized to left ventricular end-diastolic volume (QRSd/ LVEDV) could be clinical value in predicting outcome in CRT patients with mid-QRSd. These findings indicate normalized QRSd reflects myocardial conduction properties and contribute to risk stratification.

Funding Acknowledgement

Type of funding sources: None.

Hepatocellular uptake index obtained with gadoxetate disodium-enhanced magnetic resonance imaging in the assessment future liver remnant function after major hepatectomy for biliary malignancy

Background

Functional assessment of the future liver remnant (FLR) after major hepatectomy is essential but often difficult in patients with biliary malignancy, owing to obstructive jaundice and portal vein embolization. This study evaluated whether a novel index using gadoxetate disodium-enhanced MRI (EOB-MRI) could predict posthepatectomy liver failure (PHLF) after major hepatectomy for biliary malignancy.

Methods

The remnant hepatocellular uptake index (rHUI) was calculated in patients undergoing EOB-MRI before major hepatectomy for biliary malignancy. Receiver operating characteristic (ROC) curve analyses were used to evaluate the accuracy of rHUI for predicting PHLF grade B or C, according to International Study Group of Liver Surgery criteria. Multivariable logistic regression analyses comprised stepwise selection of parameters, including rHUI and other conventional indices.

Results

This study included 67 patients. The rHUI accurately predicted PHLF (area under the curve (AUC) 0.896). A cut-off value for rHUI of less than 0.410 predicted all patients who developed grade B or C PHLF. In multivariable analysis, only rHUI was an independent risk factor for grade B or C PHLF (odds ratio 2.0 × 10³, 95 per cent c.i. 19.6 to 3.8 × 10⁷; P < 0.001). In patients who underwent preoperative portal vein embolization, rHUI accurately predicted PHLF (AUC 0.885), whereas other conventional indices, such as the plasma disappearance rate of indocyanine green of the FLR and FLR volume, did not.

Conclusion

The rHUI is potentially a useful predictor of PHLF after major hepatectomy for biliary malignancy.

POS0340 VASCULAR IMAGING IN PATIENTS WITH REFRACTORY TAKAYASU ARTERITIS TREATED WITH TOCILIZUMAB: ANALYSIS FROM A RANDOMIZED CONTROLLED TRIAL

Background:

In the TAKT study, a randomized controlled trial of tocilizumab (TCZ) in patients with refractory Takayasu arteritis (TAK) in Japan, the primary end point of time to relapse after induction of remission with glucocorticoid (GC) treatment showed a trend favoring TCZ over placebo (hazard ratio 0.41 [95.41% confidence interval, 0.15-1.10; p=0.0596]),1 but the double-blind period was too short for imaging evaluation.

Objectives:

To independently evaluate vascular imaging in a post hoc analysis of radiographs from the TAKT study.

Methods:

Computed tomography images from patients in the TAKT study were evaluated by three independent radiologists who were not involved in the original trial. Patients who received TCZ and had computed tomography images available (n=28) were included. Assessments were made in 22 arteries for the change from baseline in wall thickness (primary end point), dilatation/aneurysm, stenosis/occlusion, or wall enhancement for at least 96 weeks after the start of tocilizumab treatment. Patient-level assessments were also conducted.

Results:

Among 28 patients who received at least one dose of TCZ and for whom images were available, 86.7% of 22 arteries had improved/stable (no progression) wall thickness at week 96. The proportions of patients with no progressed, partially progressed, or newly progressed lesions were 57.1%, 10.7%, and 28.6% for wall thickness, and the proportions without progressed lesions were 92.9% for dilatation/aneurysm and 85.7% for stenosis/occlusion (Figure 1). Patients with newly progressed lesions, reflecting more refractory disease, were receiving glucocorticoid doses that could not be reduced below 0.1 mg/kg/day at week 96.

Conclusion:

Approximately 60% of patients with TAK treated with tocilizumab did not experience progression in wall thickness. Few patients experienced progressive dilatation/aneurysm or stenosis/occlusion. Wall thickness progression likely resulted from refractory TAK. Patients who experience this should be monitored regularly by imaging, and additional glucocorticoid or immunosuppressive treatment should be considered to avoid vascular progression.

References:

[1]Nakaoka Y et al. Ann Rheum Dis. 2018;77:348-354.

Disclosure of Interests:

Yoshikazu Nakaoka Consultant of: Roche/Genentech, Grant/research support from: Roche/Genentech, Masahiro Yanagawa Consultant of: Roche/Genentech, Akinori Hata Consultant of: Roche/Genentech, Katsuhisa Yamashita Employee of: Chugai Pharmaceutical Co., Ltd., Norihiro Okada Employee of: Chugai Pharmaceutical Co., Ltd., Shinji Yamakido Employee of: Chugai Pharmaceutical Co., Ltd., Hiromitsu Hayashi Consultant of: Roche/Genentech, David Jayne Consultant of: Roche/Genentech, Grant/research support from: Roche/Genentech

Agriculture, biology, and environment: Twenty first century challenges and opportunities

The 6th International Conference on Agricultural and Biological Sciences (ABS 2020), was planned to be held in the People's Republic of China. Due to the COVID‐19 pandemic, ABS 2020, “Agricultural and Biological Sciences: Plant, Soil, Animal, and Environment”, was the first online conference in Agricultural and Biological Sciences history. Each paper addressed a slightly different topic and provided identifiable challenges and research key questions in agriculture, agronomy, food production and security, and environmental hazards. The role of Agricultural and Biological Sciences of China is the generation of research knowledge that influence everyday activities. There were 41 manuscripts submitted, of which 25 were accepted for publication. The research domains varied and included the role of specific plant on soil C‐cycling, haploid induction, and natural doubling of Zea mays L.; plant species and soil rhizosphere microflora; forest tree biomass succession and dynamics relevant to C‐sequestration; making sandy land agriculture friendly; plantation age on C, N, and P stoichiometry; codon uses pattern of Gnetum luofuoense C.Y. Cheng using transcriptome data; suitability of plant landscape unit and natural parks; regeneration protocol of Jatropha curcas L., etc. The purpose of this special section is to generate an improved communication among international scientists that we hope will lead to enhanced food security.

Segmental differences in Slc26a3-dependent Cl- absorption and HCO3- secretion in the mouse large intestine in vitro in Ussing chambers

The anion exchanger slc26a3 (DRA), which is mutated in congenital chloride-losing diarrhea, is expressed in the apical membrane of the cecum and middle-distal colon but not in the proximal colon of rodent large intestines. To elucidate the functional roles of DRA, we measured unidirectional 36Cl- and 22Na+ fluxes and HCO3- secretion in vitro in each of these segments using DRA-KO mice. Robust Cl- absorption, which was largely abolished after DRA deficiency, was present in the cecum and middle-distal colon but absent in the proximal colon. Na+ absorption was present in all three segments in both the control and DRA-KO mice. The luminal-Cl--dependent HCO3- secretions in the cecum and middle-distal colon were abolished in the DRA-KO mice. In conclusion, DRA mediates Cl- absorption and HCO3- secretion in the mouse cecum and middle-distal colon, and may have roles in H2O absorption and luminal acid/base regulation in these segments.

Inverse regulation of claudin-2 and -7 expression by p53 and hepatocyte nuclear factor 4α in colonic MCE301 cells

Colonic epithelial cells move up along the crypt villus axis and are differentiated into absorptive or secretory cells. Claudin-7 (CLDN7), a tight junctional protein, is mainly located at the surface of crypt, whereas CLDN2 is located at the bottom. However, the expression mechanism and function of these CLDNs are not fully understood. The expression levels of CLDN2 and CLDN7 were altered depending on the culture days in MCE301 cells derived from mouse colon. The nuclear levels of transcriptional factors p53 and hepatocyte nuclear factor 4α (HNF4α) at day 21 were higher than those at day 7. Tenovin-1 (TEN), a p53 activator, increased the nuclear levels of p53 and HNF4α. The mRNA level and promoter activity of CLDN7 were increased by TEN, whereas those of CLDN2 were decreased. The changes of CLDNs expression were inhibited by p53 and HNF4α siRNAs. The association between p53 and HNF4α was elevated by TEN. In addition, the binding of p53 and HNF4α to the promoter region of CLDN2 and CLDN7 was enhanced by TEN. Transepithelial electrical resistance was decreased by TEN, but paracellular fluxes of lucifer yellow and dextran were not. In the Ussing chamber assay, TEN increased dilution potential and the ratio of permeability of Cl^- to Na⁺. Both p53 and HNF4α were highly expressed at the surface of mouse colon crypt. We suggest that p53 and HNF4α alter the paracellular permeability of Cl^- to Na⁺ mediated by the inverse regulation of CLDN2 and CLDN7 expression in the colon.

Association between Decreased Social Participation and Depressive Symptom Onset among Community-Dwelling Older Adults: A Longitudinal Study during the COVID-19 Pandemic

OBJECTIVES

The coronavirus disease (COVID-19) pandemic has imposed restrictions on people's social behavior. However, there is limited evidence regarding the relationship between changes in social participation and depressive symptom onset among older adults during the pandemic. We examined the association between changes in social participation and the onset of depressive symptoms among community-dwelling older adults during the COVID-19 pandemic.

DESIGN

This was a longitudinal study.

SETTING

Communities in Minokamo City, a semi-urban area in Japan.

PARTICIPANTS

We recruited community-dwelling older adults aged ≥ 65 years using random sampling. Participants completed a questionnaire survey at baseline (March 2020) and follow-up (October 2020).

MEASUREMENTS

Depressive symptoms were assessed using the Two-Question Screen. Based on their social participation status in March and October 2020, participants were classified into four groups: "continued participation," "decreased participation," "increased participation," and "consistent non-participation."

RESULTS

A total of 597 older adults without depressive symptoms at baseline were analyzed (mean age = 79.8 years; 50.4% females). Depressive symptoms occurred in 20.1% of the participants during the observation period. Multivariable Poisson regression analysis showed that decreased social participation was significantly associated with the onset of the depressive symptoms, compared to continued participation, after adjusting for all covariates (incidence rate ratio = 1.59, 95% confidence interval = 1.01-2.50, p = 0.045).

CONCLUSION

Older adults with decreased social participation during the COVID-19 pandemic demonstrated a high risk of developing depressive symptoms. We recommend that resuming community activities and promoting the participation of older adults, with sufficient consideration for infection prevention, are needed to maintain mental health among older adults.

Messenger RNA expression and localization of xenin in the gastrointestinal tract in sheep

The present study aimed to determine the primary sequence of ovine xenin and clarify the mRNA expression and peptide localization of xenin in the gastrointestinal tract in sheep. The colocalization of xenin and glucose-dependent insulinotropic polypeptide was also compared in the antrum and duodenum. Analysis of the nucleotide sequence of ovine xenin revealed a high degree (97.9%) of sequence homology of the sequence between sheep and cattle, and the amino acids sequence determined for ovine xenin coincided (100%) with that of other mammalian species. Real-time quantitative PCR for ovine xenin did not show regional difference in the mRNA expression ratio of xenin. In contrast to the real-time quantitative PCR results, anti-xenin positive cells were abundantly localized in the abomasal antrum (P < 0.01) and at a lesser amount in the duodenum, but no antixenin positive cells were observed in the other regions. Anti-xenin single-positive cells were in a majority in the abomasal antrum, whereas anti-xenin single-positive cells, and anti-GIP single-positive cells, and double-positive cells were even colocalized in the duodenum. These results suggest that abomasal antrum is a major source of xenin in the ovine gastrointestinal tract.

Levels of phospholipids and triacylglycerol-containing omega 3 fatty acids in myocardial tissue of patients with myocardial infarction: analyzed by a lipidomics profiling method

Objective

According to population-based studies, low omega 3 fatty acid (omega3FA) intake and high levels of serum triacylglycerol (TAG) are associated with cardiovascular diseases. Recent advances in mass spectrometry allow molecular lipid (lipidomics) profiling, which may enhance cardiovascular risk prediction. In this study, we assessed the levels of omega3FA-containing phospholipids (PL) and TAG in myocardial tissues of patients with and without myocardial infarction (MI) using a lipidomics profiling method.

Methods

We performed lipidomics profiling of human left atrial appendage (LAA) tissue of 29 consecutive patients receiving off-pump coronary bypass surgery with standard LAA resection. The patients were divided into the MI group (n=7) and an age- and gender-matched non-MI group (n=7).

Results

Lipidomics profiling revealed that the MI group tended to have low levels of phosphatidylcholines (PC), phosphatidylethanolamine (PE), lysophosphatidylethanolamine (LPE), and plasmalogen, and high levels of TAG species. Individual molecular species containing omega3FA, such as PC (18:0/20:5; 3,200±1,200 vs. 4,500±910 pmol/g tissue, p=0.04) and plasmalogen (18:1/20:5; 57,000±21,000 vs. 91,000±28,000 pmol/g tissue, p=0.02), were significantly lower in the MI group than in the non-MI group.

Conclusions

To our knowledge, this is the first study to determine the levels of omega3FA-containing PL and TAG in myocardial tissue using lipidomics profiling. We discovered that lower levels of omega3FA-containing PL and higher levels of TAG existed in myocardial tissues of patients with MI than in those of patients without MI. Accordingly, the lipidomics profiling method for human myocardial tissue may be useful for developing therapy targets for cardiovascular diseases.

Funding Acknowledgement

Type of funding source: Public grant(s) – National budget only. Main funding source(s): MEXT/JSPS KAKENHI Grant

Characterization of thromboembolic and bleeding risks in cancer patients with acute myocardial infarction under the use of guideline-recommended dual-antiplatelet therapy

Background

Atherosclerotic cardiovascular disease including acute myocardial infarction (AMI) has become one of major co-existing diseases in cancer patients due to their improved survival rate. Current guideline recommends dual-antiplatelet therapy (DAPT) in patients with AMI. Given that the presence of cancer elevates not only coagulability but bleeding risks, these substrate may further worsen cardiovascular outcomes and bleeding risks in cancer subjects with AMI receiving DAPT.

Methods

We retrospectively analyzed 712 AMI patients treated by primary PCI with drug-eluting stent and DAPT between 2007 and 2017. The diagnosis of cancer was determined through medical record review. Clinical characteristics, thromboembolic (=all-cause death+non-fatal MI+stroke) and bleeding events were compared in AMI subjects with vs. without cancer.

Results

Cancer was identified in 11.1% (=79/712) of study subjects. Of these, around 40% of them had gastrointestinal cancer (=35/79), followed by lung cancer (=5/79) and breast cancer (=8/79). Cancer patients were more likely to be older (77±7 v. 69±13 years, p&lt;0.001) with a history of Af (25 v. 10%, p&lt;0.001), CKD (eGFR&lt;60: 60 v. 42%, p=0.002), anemia (hemoglobin: 12.8±1.8 v. 13.9±1.8 g/dl, p&lt;0.001). Under anti-thrombotic (DAPT=86%, triple-antiplatelet therapy=14%) and optimal medical therapies (ACE-I=90%, beta-blocker=76%, statin=96%), more frequent occurrence of thromboembolic events was observed in patients with cancer (34.2 v. 12.6%, p=0.004, Picture). Furthermore, the presence of cancer was associated with more than four times greater risk of bleeding events compared to non-cancer subjects (18.9 v. 4.3%, p&lt;0.001, Picture). In particular, the frequency of both major (10.1 vs. 3.3%, p=0.003) and minor (8.9 vs. 0.9%, p&lt;0.001) bleeding events was significantly higher in patients with cancer. In multivariate analysis, cancer independently predicted bleeding events (Table).

Conclusions

Under the use of guideline recommended DAPT, the concomitance of cancer in AMI subjects was a predictor for thromboembolic as well as bleeding events. In particular, the relationship between cancer and bleeding was significant. These observations underscore the appropriate selection and duration of anti-thrombotic agents in AMI subjects with cancer.

Cardiac/Bleeding Events in AMI Subjects

Funding Acknowledgement

Type of funding source: None

Thigh intramuscular fat predicts the prognosis in patients in non-ischemic cardiomyopathy with reduced ejection fraction

Background

Skeletal muscle atrophy is an independent prognostic predictor for patients with chronic heart failure, and the concept of sarcopenia is drawing attention. Furthermore, the importance of not only muscle mass but also intramuscular fat (IMF) has been pointed out. However, there is a lack of consensus on the implications of ectopic fat for the prognosis in patients with non-ischemic cardiomyopathy.

Purpose

We investigated whether ectopic fat in the thigh affects the prognosis with non-ischemic cardiomyopathy.

Methods

We recruited 105 patients who were diagnosed with non-ischemic cardiomyopathy by cardiac catheterization and echocardiographic date between September 2017 and November 2019. Finally 73 patients with reduced EF (EF 40% or less) enrolled in this prospective study. Functional status was evaluated by using cardiopulmonary exercise test at baseline. All patients were measured quantity of epicardial fat and thigh IMF percentage (%IMF) using computed tomography scan. Demographic, laboratory and echocardiographic date were collected from the patients' medical records. Clinical endpoints were unexpected readmission.

Results

During the follow-up period 18 patients had adverse events. The %IMF was significantly higher in the group with adverse events than without (5.57±5.70 and 3.02±2.44%, respectively; p&lt;0.01). Spearman correlation coefficient analysis showed a modest correlation between %IMF and lower limb extension strength (Spearman r=−0.280; p=0.0315), but there was no significant correlation between %IMF and exercise tolerance such as anaerobic threshold and peak oxygen uptake. Patients were divided into 2 groups according to the median values of %IMF. Kaplan-Meier analysis demonstrated that events were significantly higher in the high %IMF group (log-rank p=0.033). Multivariate Cox regression analysis adjusted for left ventricular end-diastolic diameter and peak ventricular oxygen consumption found %IMF as an independent factor of adverse events (hazard ratio 1.545; 95% confidential interval 1.151–2.087; p=0.004).

Conclusions

In non-ischemic cardiomyopathy patients with reduced EF, %IMF may have important adverse consequences such as increased cardiac-related events.

Kaplan-Meier curves

Funding Acknowledgement

Type of funding source: None

Regional muscle-adipose distribution is different in patients with heart failure with preserved or reduced ejection fraction

Background

Epicardial adipose tissue (EAT) has been recognized to contribute inflammatory activity and atherosclerosis. On the other hand, it has been reported that the volume of EAT is lower in non-ischemic heart failure (HF) patients than healthy individuals. However, the difference in regional muscle-adipose distribution including EAT between HF with preserved ejection fraction (HFpEF) and HF reduced ejection fraction (HFrEF) has not been investigated. In addition, we investigated whether distribution of body composition contributed to exercise capacity.

Methods

The study included 105 non-ischemic HF patients diagnosed by cardiac catheterization between September 2017 and November 2019. Epicardial, abdominal and thigh muscle and adipose tissue volume were measured by computed tomography (CT), and exercise tolerance was evaluated by symptom-limited cardiopulmonary exercise test.

Results

Patients were divided into 2 groups according to the left ventricular ejection fraction, ≥40% as HFpEF (n=28) or &lt;40% as HFrEF (n=77). There was no significant difference comorbidity, including hypertension, dyslipidemia, chronic kidney disease, and body mass index. Plasma B-type natriuretic peptide level was significantly higher in HFrEF than HFpEF group (146.2 vs 393.2 pg/ml, p&lt;0.01), whereas, high-sensitive troponin T level was not different between two groups. Although there was no significant difference in BMI between two groups, the volume of EAT was significantly higher in HFpEF than HFrEF group (81.8 vs 136.4 ml, p=0.01). On the other hand, HFpEF had more thigh adipose tissue compared with HFrEF group (54.6 vs 42.1 ml, p=0.03). There were negative correlations between EAT volume and parameters of exercise capacity such as anaerobic threshold (r=−0.42, p&lt;0.01) and peak VO2 (r=−0.32, p&lt;0.01). Muscle volume itself does not corelate with these parameters.

Conclusion

In patient with nonischemic HF, the pattern of regional adipose distribution may have important role in pathologically. HFpEF and HFrEF has different pattern despite similar body mass index. These differences may be related to impaired exercise tolerance in these 2 different types of HF.

Correlation between EAT and AT, peak VO2

Funding Acknowledgement

Type of funding source: None

Effect of therapeutic plasma exchange on phenytoin plasma concentration in patients receiving intravenous fosphenytoin therapy

We report for patients with encephalitis treated with plasma exchange (PE) and fosphenytoin. In patient 1, phenytoin levels decreased on the maintenance dose, and the phenytoin concentration was <10 μg/mL on day 12 of administration. In patient 2, the phenytoin levels was <10 μg/mL on day 4. Increasing the fosphenytoin dose pushed the phenytoin level into therapeutic range. There were no differences between the areas under the concentration-time curve of phenytoin with and without PE. We previously reported a decline in phenytoin levels after prolonged use of fosphenytoin. Therefore, dose adjustment of fosphenytoin in patients undergoing PE may be unnecessary.