The influence of anastomotic techniques on postoperative anastomotic complications: Results of the Oesophago-Gastric Anastomosis Audit

BACKGROUND

The optimal anastomotic techniques in esophagectomy to minimize rates of anastomotic leakage and conduit necrosis are not known. The aim of this study was to assess whether the anastomotic technique was associated with anastomotic failure after esophagectomy in the international Oesophago-Gastric Anastomosis Audit cohort.

METHODS

This prospective observational multicenter cohort study included patients undergoing esophagectomy for esophageal cancer over 9 months during 2018. The primary exposure was the anastomotic technique, classified as handsewn, linear stapled, or circular stapled. The primary outcome was anastomotic failure, namely a composite of anastomotic leakage and conduit necrosis, as defined by the Esophageal Complications Consensus Group. Multivariable logistic regression modeling was used to identify the association between anastomotic techniques and anastomotic failure, after adjustment for confounders.

RESULTS

Of the 2238 esophagectomies, the anastomosis was handsewn in 27.1%, linear stapled in 21.0%, and circular stapled in 51.9%. Anastomotic techniques differed significantly by the anastomosis sites (P < .001), with the majority of neck anastomoses being handsewn (69.9%), whereas most chest anastomoses were stapled (66.3% circular stapled and 19.3% linear stapled). Rates of anastomotic failure differed significantly among the anastomotic techniques (P < .001), from 19.3% in handsewn anastomoses, to 14.0% in linear stapled anastomoses, and 12.1% in circular stapled anastomoses. This effect remained significant after adjustment for confounding factors on multivariable analysis, with an odds ratio of 0.63 (95% CI, 0.46-0.86; P = .004) for circular stapled versus handsewn anastomosis. However, subgroup analysis by anastomosis site suggested that this effect was predominantly present in neck anastomoses, with anastomotic failure rates of 23.2% versus 14.6% versus 5.9% for handsewn versus linear stapled anastomoses versus circular stapled neck anastomoses, compared with 13.7% versus 13.8% versus 12.2% for chest anastomoses.

CONCLUSIONS

Handsewn anastomoses appear to be independently associated with higher rates of anastomotic failure compared with stapled anastomoses. However, this effect seems to be largely confined to neck anastomoses, with minimal differences between techniques observed for chest anastomoses. Further research into standardization of anastomotic approach and techniques may further improve outcomes.

High-Density, Localized Quantum Emitters in Strained 2D Semiconductors

Two-dimensional chalcogenide semiconductors have recently emerged as a host material for quantum emitters of single photons. While several reports on defect- and strain-induced single-photon emission from 2D chalcogenides exist, a bottom-up, lithography-free approach to producing a high density of emitters remains elusive. Further, the physical properties of quantum emission in the case of strained 2D semiconductors are far from being understood. Here, we demonstrate a bottom-up, scalable, and lithography-free approach for creating large areas of localized emitters with high density (∼150 emitters/um²) in a WSe₂ monolayer. We induce strain inside the WSe₂ monolayer with high spatial density by conformally placing the WSe₂ monolayer over a uniform array of Pt nanoparticles with a size of 10 nm. Cryogenic, time-resolved, and gate-tunable luminescence measurements combined with near-field luminescence spectroscopy suggest the formation of localized states in strained regions that emit single photons with a high spatial density. Our approach of using a metal nanoparticle array to generate a high density of strained quantum emitters will be applied to scalable, tunable, and versatile quantum light sources.

POS0859 C-REACTIVE PROTEIN AND INTERLEUKIN-6: POTENTIAL BIOMARKERS OF DISEASE ACTIVITY AND TREATMENT RESPONSE IN SYSTEMIC SCLEROSIS-INTERSTITIAL LUNG DISEASE

Background

Clinically feasible and valid biomarkers of systemic sclerosis-interstitial lung disease (SSc-ILD) are needed. While promising candidate biomarkers are under investigation (e.g., KL-6, CCL-8), clinical assays for these proteins are not currently available. C-reactive protein (CRP) measurements are feasible, cost-effective, and have been shown to predict mortality in SSc.1 Measuring interleukin (IL)-6, a proinflammatory cytokine implicated in SSc-ILD pathogenesis, is also feasible in most clinical settings.

Objectives

(1) To investigate whether CRP and IL-6 levels change in response to treatment with immunosuppression in SSc-ILD; (2) To explore whether the change in CRP and IL-6 predict the future course of forced vital capacity (FVC).

Methods

CRP and IL-6 levels were measured in serum at baseline and after 12 months in participants of Scleroderma Lung Study (SLS) II (patients with active SSc-ILD receiving 24 months of mycophenolate or 12 months cyclophosphamide followed by 12 months of placebo2). Measured values were log-transformed to remove skewness. The FVC%-predicted was measured every 3 months over the course of 24 months. Spearman’s correlations evaluated the relationship between baseline CRP or IL-6 measurements and other patient parameters. Paired t-tests were used to compare the change in individual CRP and IL-6 measurements from baseline to 12 months. Linear mixed effects models were used to examine the relationship between the change in CRP and IL-6 (baseline to 12 months) and the subsequent course of the FVC (12 to 24 months). All analysis were performed for the entire cohort and separately by treatment arm.

Results

Of the 142 participants of SLS II, 101 had CRP and IL-6 measurements at baseline and 12 months. Baseline CRP and IL-6 levels correlated significantly with higher modified Rodnan skin score (CRP: r=0.3, P=0.005; IL-6: r=0.2, P=0.01) and shorter disease duration (CRP: r=-0.3, P=0.005; IL-6: r=-0.2, P=0.01) and were higher in patients with diffuse SSc (CRP: P=0.007; IL-6: P=0.01). Relationships to baseline FVC and DLCO were not observed. CRP decreased significantly from baseline to 12 months in the whole group (P=0.01), but the decrease was slightly greater in patients randomized to mycophenolate versus cyclophosphamide (-0.47 vs. -0.33 ug/mL). IL-6 also decreased from baseline to 12 months in the whole group with a trend towards significance (P=0.10) (Figure 1). The mean decrease in IL-6 was again slightly greater in patients randomized to mycophenolate versus cyclophosphamide (-0.31 vs. -0.10 pg/mL). After controlling for baseline FVC and treatment arm in the mixed effects model, there was a relationship between the decrease in CRP from baseline to 12 months and an improved course of FVC 12 to 24 months (Estimate -0.64), but this did not reach significance (P=0.14). However, after controlling for baseline FVC and treatment arm, a greater decrease in IL-6 from baseline to 12 months was significantly associated with a greater improvement in FVC from 12 to 24 months (Estimate -1.28; P=0.01).

Figure 1.

Change in CRP (A) and IL-6 (B) from baseline to 12 months by treatment arm in SLS II. CYC=cyclophosphamide (Blue), MMF=mycophenolate (red)

Conclusion

Patients with active SSc-ILD receiving one year of immunosuppressive therapy in the SLS II study experienced reductions in their CRP and IL-6 levels over this interval. The magnitude of the decrease in CRP and IL-6 over the first year also correlated with the course of FVC over the ensuing 12 months. These findings suggest a dynamic relationship between CRP and IL-6 measurements and the course of SSc-ILD in patients on immunosuppressive therapy. Further investigation of these findings is warranted.

References

[1]Liu et al. Arthritis Care Res 2013.

[2]Tashkin et al. Lancet Resp Med 2016.

Disclosure of Interests

Elizabeth Volkmann Speakers bureau: Boehringer Ingelheim, Consultant of: Boehringer Ingelheim, Grant/research support from: Forbius, Kadmon, Horizon, Boehringer Ingelheim, Donald Tashkin: None declared, Holly Wilhalme: None declared, Marka Lyons: None declared, Grace Kim: None declared, Jonathan Goldin: None declared, Michael Roth Grant/research support from: Genentech, Shervin Assassi Consultant of: Boehringer Ingelheim

POS0852 SYMPTOMS OF GASTROESOPHAGEAL REFLUX ARE A BETTER PREDICTOR OF SYSTEMIC SCLEROSIS-RELATED INTERSTITIAL LUNG DISEASE PROGRESSION THAN QUANTITATIVE RADIOGRAPHIC ASSESSMENT OF ESOPHAGEAL PARAMETERS

Background

Esophageal dysfunction affects the majority of patients with systemic sclerosis (SSc). Gastroesophageal reflux (GERD)-associated microaspiration may serve as an inciting and/or exacerbating factor in the pathogenesis of interstitial lung disease (ILD) in SSc. Few studies have investigated the relationship between objective measures of esophageal involvement in SSc and the progression of SSc-ILD.

Objectives

(1) To investigate whether patient-reported symptoms of GERD predict SSc-ILD severity and progression; (2) To explore whether quantitative radiographic measurements of esophageal parameters predict SSc-ILD severity and progression.

Methods

Participants of Scleroderma Lung Study (SLS) II (24 months of mycophenolate versus 12 months cyclophosphamide followed by 12 months of placebo in patients with active SSc-ILD) were included.1 The UCLA SCTC GIT 2.0 was used to assess the severity of reflux at baseline. Quantitative image analysis was used to calculate the diameter and area of the esophagus in the area of maximum dilation. Univariate and multivariable linear regression analyses were used to evaluate the relationship between baseline reflux scores/esophageal parameters and the severity and progression of SSc-ILD based on the quantitative radiographic extent of ILD (QILD) and fibrosis (QLF) in the lobe of maximum involvement (LM). All multivariable models controlled for treatment arm and baseline ILD severity, as well as proton pump inhibitor (PPI) use.

Results

Among the 141 of 142 SLS II participants with patient-reported reflux scores at baseline, the mean score was 0.57, indicating moderate reflux. The mean maximal esophageal diameter and area at baseline were 22 mm and 242 mm2, respectively. There were no significant correlations between reflux scores, esophageal diameter, esophageal area and QILD-LM and QLF-LM at baseline. However, in the 96 participants with HRCT scans available at 24 months, increased reflux scores were significantly associated with worsening of QLF-LM and QILD-LM (Figure 1). Even after controlling for disease severity at baseline, treatment arm and PPI use, reflux scores remained significantly associated with change in QLF-LM (P-value 0.05) and QILD-LM (P-value 0.003). Neither the maximum esophageal area, nor the maximum esophageal diameter was associated with the change in QILD-LM or QLF-LM in univariate or multivariate analyses.

Figure 1.

Increased reflux scores at baseline are associated with increased progression (worsening) of QILD (A) and QLF (B) in the lobe of maximum involvement in patients with SSc-ILD.

Conclusion

Increased self-reported reflux was independently associated with worsening radiographic fibrosis and ILD in patients receiving treatment for SSc-ILD. The maximum esophageal diameter and esophageal area did not correlate with reflux scores and did not predict severity or progression of SSc-ILD. These findings illustrate the importance of eliciting a careful patient history of reflux symptoms in patients with ILD and further highlight the need for improved objective measures of esophageal dysfunction in SSc.

References

[1]Tashkin et al. Lancet Resp Med 2016.

Disclosure of Interests

Elizabeth Volkmann Speakers bureau: Boehringer Ingelheim, Consultant of: Boehringer Ingelheim, Grant/research support from: Forbius, Horizon, Kadmon, Boehringer Ingelheim, Donald Tashkin: None declared, Mei Leng: None declared, Grace Kim: None declared, Jonathan Goldin: None declared, Michael Roth Grant/research support from: Genentech

POS0068 CHANGES IN QUANTITATIVE INTERSTITIAL LUNG DISEASE SCORES ON HIGH-RESOLUTION CT IN IDIOPATHIC INFLAMMATORY MYOSITIS

Background

The idiopathic inflammatory myopathies (IIM) are autoimmune connective tissue diseases affecting skeletal muscle, skin and other organ systems. IIM-related interstitial lung disease (IIM-ILD) is the most common extra-muscular manifestation, being the leading cause of morbidity and mortality. Several studies have suggested that ILD pattern based on chest high-resolution computed tomography (HRCT) can be related to disease course and treatment response, but the results vary considerably. Moreover, the clinical impact of the quantitative ILD (QILD) score, a validated computer-aided scoring system in assessing ILD severity from HRCT, and its longitudinal changes have not yet been evaluated in IIM-ILD.

Objectives

This study aims to investigate ILD patterns and QILD scores in patients with IIM-ILD, to identify their clinical impact, and to delineate longitudinal changes of QILD measurement.

Methods

A total of 80 patients with IIM (polymyositis 22, and dermatomyositis 58) who underwent at least 2 times of serial HRCT scans were included. Visual ILD patterns were assessed by multiple thoracic radiologists. Quantitative analysis of HRCT was presented as total extent of QILD scores (%) in whole lung and most severe zone. Individual time-estimated ΔQILD score between first 2 visits was derived using a linear approximation of yearly change, where the duration of median (IQR) was 1.0 (0.4-1.6) years in the first 2 HRCT scans.

Results

The median (IQR) age of the patients was 52.0 (43.5-58.5) years and 60 (75.0%) were women. Baseline median score of whole lung-QILD and most severe zone-QILD were 28.1% (19.1-43.8) and 68.0% (45.5-81.8), respectively, and QILD score showed significant correlations with pulmonary function tests (r=-0.349, p=0.002 for % predicted forced vital capacity; and r=-0.381, p=0.001 for % predicted diffusing capacity for carbon monoxide). The individual time-estimated yearly ΔQILD score between first 2 visits presented that approximately half of the patients showed improvement or stability in QILD scores; however, when patients were sorted by visual assessment in ILD subtype on HRCT, approximately two-thirds of the patients with usual interstitial pneumonia (UIP) pattern were aggravated in QILD scores and less than half of subjects with nonspecific interstitial pneumonia and organizing pneumonia were aggravated (Figure 1, 80% for UIP vs. 44.4% for non-UIP, p=0.013). There was no immunosuppressive drugs related to meaningful improvement in QILD scores during first 2 visits. Notably, we observed significant aggravation of QILD scores in tacrolimus users (n=7, median time-estimated whole lung-yarly ΔQILD 20.3 (2.7-38.4)) compared with tacrolimus non-users (n=73, median time estimated whole lung-yearly ΔQILD -1.2 (-8.3-6.5)). Among 80 patients, 6 (7.5%) were died due to various lung complications. Higher baseline QILD scores were noted in deaths (median whole lung-QILD 45.4 (32.9-56.5)) than in survivors (median whole lung-QILD 26.9 (19.0-42.4)), albeit not significant (p=0.084). Poor survival rate was observed in patients with high grade of ground glass opacity by visual assessment in right upper lobe (log-rank test, p=0.042). Among subgroup of patients with 3 serial HRCT scans (n=41), dynamic changes of four distinct patterns (improving, worsening, convex, and concave) were observed.

Figure 1.

Cleveland dot plot of individual time-estimated yearly ΔQILD during fist 2 visits.

Conclusion

The changes in QILD score in IIM-ILD are dynamic and present different by visual assessment. QILD score has the potential for evaluation of the severity changes, prognosis and medication response in patients with IIM-ILD.

References

[1]Tashkin DP, et al. Ann Rheum Dis 2016;75(2):374-81.

7 truncated values in the graph A. NSIP: nonspecific interstitial pneumonia; OP: organizing pneumonia; UIP: usual interstitial pneumonia.

Disclosure of Interests

None declared

Textbook outcome following oesophagectomy for cancer: international cohort study

Background

Textbook outcome has been proposed as a tool for the assessment of oncological surgical care. However, an international assessment in patients undergoing oesophagectomy for oesophageal cancer has not been reported. This study aimed to assess textbook outcome in an international setting.

Methods

Patients undergoing curative resection for oesophageal cancer were identified from the international Oesophagogastric Anastomosis Audit (OGAA) from April 2018 to December 2018. Textbook outcome was defined as the percentage of patients who underwent a complete tumour resection with at least 15 lymph nodes in the resected specimen and an uneventful postoperative course, without hospital readmission. A multivariable binary logistic regression model was used to identify factors independently associated with textbook outcome, and results are presented as odds ratio (OR) and 95 per cent confidence intervals (95 per cent c.i.).

Results

Of 2159 patients with oesophageal cancer, 39.7 per cent achieved a textbook outcome. The outcome parameter ‘no major postoperative complication’ had the greatest negative impact on a textbook outcome for patients with oesophageal cancer, compared to other textbook outcome parameters. Multivariable analysis identified male gender and increasing Charlson comorbidity index with a significantly lower likelihood of textbook outcome. Presence of 24-hour on-call rota for oesophageal surgeons (OR 2.05, 95 per cent c.i. 1.30 to 3.22; P = 0.002) and radiology (OR 1.54, 95 per cent c.i. 1.05 to 2.24; P = 0.027), total minimally invasive oesophagectomies (OR 1.63, 95 per cent c.i. 1.27 to 2.08; P &lt; 0.001), and chest anastomosis above azygous (OR 2.17, 95 per cent c.i. 1.58 to 2.98; P &lt; 0.001) were independently associated with a significantly increased likelihood of textbook outcome.

Conclusion

Textbook outcome is achieved in less than 40 per cent of patients having oesophagectomy for cancer. Improvements in centralization, hospital resources, access to minimal access surgery, and adoption of newer techniques for improving lymph node yield could improve textbook outcome.

Textbook outcome following oesophagectomy for cancer: international cohort study

BACKGROUND

Textbook outcome has been proposed as a tool for the assessment of oncological surgical care. However, an international assessment in patients undergoing oesophagectomy for oesophageal cancer has not been reported. This study aimed to assess textbook outcome in an international setting.

METHODS

Patients undergoing curative resection for oesophageal cancer were identified from the international Oesophagogastric Anastomosis Audit (OGAA) from April 2018 to December 2018. Textbook outcome was defined as the percentage of patients who underwent a complete tumour resection with at least 15 lymph nodes in the resected specimen and an uneventful postoperative course, without hospital readmission. A multivariable binary logistic regression model was used to identify factors independently associated with textbook outcome, and results are presented as odds ratio (OR) and 95 per cent confidence intervals (95 per cent c.i.).

RESULTS

Of 2159 patients with oesophageal cancer, 39.7 per cent achieved a textbook outcome. The outcome parameter 'no major postoperative complication' had the greatest negative impact on a textbook outcome for patients with oesophageal cancer, compared to other textbook outcome parameters. Multivariable analysis identified male gender and increasing Charlson comorbidity index with a significantly lower likelihood of textbook outcome. Presence of 24-hour on-call rota for oesophageal surgeons (OR 2.05, 95 per cent c.i. 1.30 to 3.22; P = 0.002) and radiology (OR 1.54, 95 per cent c.i. 1.05 to 2.24; P = 0.027), total minimally invasive oesophagectomies (OR 1.63, 95 per cent c.i. 1.27 to 2.08; P < 0.001), and chest anastomosis above azygous (OR 2.17, 95 per cent c.i. 1.58 to 2.98; P < 0.001) were independently associated with a significantly increased likelihood of textbook outcome.

CONCLUSION

Textbook outcome is achieved in less than 40 per cent of patients having oesophagectomy for cancer. Improvements in centralization, hospital resources, access to minimal access surgery, and adoption of newer techniques for improving lymph node yield could improve textbook outcome.

Attenuation of intrinsic aging of the skin via elimination of senescent dermal fibroblasts with senolytic drugs

BACKGROUND

Skin aging is caused by numerous factors that result in structural and functional changes in cutaneous components. Research has shown that senescent cells are known to accumulate in skin aging, however, the role of senescent cells in skin aging has not been defined.

OBJECTIVES

To elucidate the role of senescent cell in skin aging, we evaluated the effect of known senolytic drugs on senescent dermal fibroblasts.

METHODS

Primary human dermal fibroblasts (HDFs) were induced to senescence by long-term passaging, UV irradiation, and H2O2 treatment. Cell viability was measured after treatment of ABT-263 and ABT-737 on HDFs. Young and aged hairless mice were intradermally injected with drugs or vehicle on the dorsal skin for 10 days. Skin specimens were obtained and reverse-transcription quantitative PCR, western blotting, and histological analysis were performed.

RESULTS

We found that ABT-263 and ABT-737 induced selective clearance of senescent dermal fibroblasts, regardless of the method of senescence induction. Aged mouse skin treated with ABT-263 or ABT-737 showed increased collagen density, epidermal thickness, and proliferation of keratinocytes, as well as decreased senescence-associated secretory phenotypes, such as MMP-1 and IL-6.

CONCLUSIONS

Taken together, our results indicate that selective clearance of senescent skin cells can attenuate and improve skin aging phenotypes and that senolytic drugs may be of potential use as new therapeutic agents for treating aging of the skin.

Right ventricle function before and after different types of cardiac surgery

Funding Acknowledgements

Type of funding sources: None.

Background

Right ventricular (RV) dysfunction is an established independent predictor for adverse prognosis in a heterogeneous group of cardiac surgery patients (pts). However, there is lack of information about normal and abnormal dynamics of echocardiographic parameters for different types of cardiac surgery.

The aim of the study was to define changes in RV parameters after cardiac surgery.

Methods

sixty-five pts (39 men, 62 ± 9 years old) were selected into prospective study (NCT03953755). There were the groups of pts with left-sided valves surgery with/ without tricuspid valve (TV) repair, and pts with left-sided coronary artery bypass surgery without lesions of right coronary artery were included control group. A transthoracic echocardiography assessment before and an average of 101 days (88-115) following the operation was performed. Tricuspid annular plane systolic excursion (TAPSE), fractional area change (FAC), strain of the RV free wall (SRV), and right atrial volume were assessed in groups of patients with and without tricuspid valve repair as in CABG-group. Follow-up during 12 months was available in all pts.

Results

Valve repair for secondary tricuspid regurgitation was performed in nineteen patients undergoing left-sided valve surgery. Thirty-six patients had repair and/or replacement of left-sided valves without a tricuspid valve operation. There was a strong correlation between TAPSE, FAC, and RV strain before the operation (R = 0.61-0.67, p &lt; 0.000001). However, there was no correlation between TAPSE and FAC; TAPSE, and RV strain after the operation. TAPSE and RV strain significantly decreased after the operations and were below the normal range in both the groups with valve surgery, whereas, the CABG group showed only significantly TAPSE decreasing, RV strain was unchanged. TAPSE was 20 ± 5mm vs. 13 ± 2 mm, p &lt; 0.0003 for the group which underwent tricuspid valve repair; 22 ± 4mm vs. 14 ± 4 mm, p &lt; 0.0000001 for the group with tricuspid valves which were not operated on; 25 ± 6mm vs. 16 ± 3 mm, p &lt; 0.009 for CABG group. There was no difference in TAPSE and SRV ranges among patients with and without tricuspid valve repair. Dynamics in SRV didn’t correlate with patients’ clinical status or with normalized right chambers volumes. An increase in FAC correlated with a decrease in right chamber sizes after operations (R=-0.46, p &lt; 0.03). More prominent decreasing in TAPSE was connected in adverse events during follow-up (dTAPSE 6.7 ± 3.5 mm vs. 12.7 ± 5.1 mm, p &lt; 0.02)

Conclusion

TAPSE significantly decreases in all patients after CABG or valve cardiac operations with/without tricuspid valve repair, range of TAPSE were below normal standard in all patients. However more severe decreasing in TAPSE is connected with further adverse outcomes.

Bactericidal and antibiofilm properties of Rumex japonicus Houtt. on multidrug-resistant Staphylococcus aureus isolated from milk

Multidrug-resistant (MDR) Staphylococcus aureus and its biofilm formation have been challenging to control in milk and dairy industries. Biofilms formed by Staph. aureus may result in the failure of antibacterial agents and disinfectants to penetrate the biofilm in an attempt to control contamination. Novel natural antibacterial agents are required to combat MDR bacteria and biofilms. In this study, we evaluated the bactericidal, antibiofilm, and antimotility effects of Rumex japonicus Houtt. (RJH) extract on MDR Staph. aureus isolated from milk. The RJH extract exhibited good antibacterial activity against MDR strains with minimum inhibitory concentrations (MIC) ranging from 0.78 to 6.25 mg/mL and minimum bactericidal concentrations ranging from 3.125 to 12.5 mg/mL. The extract showed strong inhibition of biofilm formation (81.9%) at sub-MIC value and eradication of biofilm at higher concentrations. The motility of Staph. aureus was effectively blocked by the extract. Major compounds emodin, chrysophanol, and physcion were identified in RJH extract using HPLC-linear trap quadrupole (LTQ)/Orbitrap-mass spectrometry. The extract was nontoxic to human epithelial cell lines such as Caco-2 and HT-29 cell lines at concentrations ranging from 0.1 to 0.5 mg/mL, and from 0.1 to 0.75 mg/mL, respectively. These findings suggest that RJH extract could be an alternative to synthetic preservatives in milk and dairy products.

Development of postbiotics by whey bioconversion with Enterococcus faecalis M157 KACC81148BP and Lactococcus lactis CAU2013 KACC81152BP for treating periodontal disease and improving gut health

This study developed postbiotics with whey bioconversion product produced by Enterococcus faecalis M157 KACC 81148BP, and mixed whey bioconversion products produced by E. faecalis M157 KACC 81148BP and Lactococcus lactis ssp. lactis CAU2013 KACC 81152BP to alleviate periodontitis (PD) and to improve gut health. The powdered whey bioconversion product (EF) produced by E. faecalis M157 KACC 81148BP, mixed whey bioconversion products (EF+LL) from E. faecalis M157 KACC 81148BP and L. lactis CAU2013 KACC 81152BP, and phosphate-buffered saline (PBS; control) were administered orally to PD-induced rats for 8 wk. Infiltration of inflammatory cells and epithelial proliferation in periodontal tissue were found in control, but the lesions were reduced in PD+EF group (administration of EF to PD-induced rats), and no lesions were observed in PD+EF+LL group (administration of EF+LL to PD-induced rats). The bone loss volumes in PD+EF and PD+EF+LL groups were lower than in control. Cytokine production levels related to inflammation were lower and antioxidative stress markers were higher in PD+EF and PD+EF+LL groups than in control for both periodontal tissue and gut. The ratios of Lactobacillus spp. in gut microbiome of PD+EF and PD+EF+LL groups were higher than in control. These results indicate that the whey bioconversion product produced by E. faecalis M157 KACC 81148BP, and mixed whey bioconversion products produced by E. faecalis M157 KACC 81148BP and L. lactis CAU2013 KACC 81152BP are effective on relieving periodontitis and improving the gut health.

Direct growth of hexagonal boron nitride on non-metallic substrates and its heterostructures with graphene

Hexagonal boron nitride (h-BN) and its heterostructures with graphene are widely investigated van der Waals (vdW) quantum materials for electronics, photonics, sensing, and energy storage/transduction. However, their metal catalyst-based growth and transfer-based heterostructure assembly approaches present impediments to obtaining high-quality and wafer-scale quantum material. Here, we have presented our perspective on the synthetic strategies that involve direct nucleation of h-BN on various dielectric substrates and its heterostructures with graphene. Mechanistic understanding of direct growth of h-BN via bottom-up approaches such as (a) the chemical-interaction guided nucleation on silicon-based dielectrics, (b) surface nitridation and N+ sputtering of h-BN target on sapphire, and (c) epitaxial growth of h-BN on sapphire, among others, are reviewed. Several design methodologies are presented for the direct growth of vertical and lateral vdW heterostructures of h-BN and graphene. These complex 2D heterostructures exhibit various physical phenomena and could potentially have a range of practical applications.

Postoperative outcomes in oesophagectomy with trainee involvement

BACKGROUND

The complexity of oesophageal surgery and the significant risk of morbidity necessitates that oesophagectomy is predominantly performed by a consultant surgeon, or a senior trainee under their supervision. The aim of this study was to determine the impact of trainee involvement in oesophagectomy on postoperative outcomes in an international multicentre setting.

METHODS

Data from the multicentre Oesophago-Gastric Anastomosis Study Group (OGAA) cohort study were analysed, which comprised prospectively collected data from patients undergoing oesophagectomy for oesophageal cancer between April 2018 and December 2018. Procedures were grouped by the level of trainee involvement, and univariable and multivariable analyses were performed to compare patient outcomes across groups.

RESULTS

Of 2232 oesophagectomies from 137 centres in 41 countries, trainees were involved in 29.1 per cent of them (n = 650), performing only the abdominal phase in 230, only the chest and/or neck phases in 130, and all phases in 315 procedures. For procedures with a chest anastomosis, those with trainee involvement had similar 90-day mortality, complication and reoperation rates to consultant-performed oesophagectomies (P = 0.451, P = 0.318, and P = 0.382, respectively), while anastomotic leak rates were significantly lower in the trainee groups (P = 0.030). Procedures with a neck anastomosis had equivalent complication, anastomotic leak, and reoperation rates (P = 0.150, P = 0.430, and P = 0.632, respectively) in trainee-involved versus consultant-performed oesophagectomies, with significantly lower 90-day mortality in the trainee groups (P = 0.005).

CONCLUSION

Trainee involvement was not found to be associated with significantly inferior postoperative outcomes for selected patients undergoing oesophagectomy. The results support continued supervised trainee involvement in oesophageal cancer surgery.

Stress echocardiography and outcomes after cardiac surgery in patients with ischemic mitral regurgitation

Background

Ischaemic mitral regurgitation (IMR) is a frequent complication of coronary artery disease. This is generally associated with double mortality rates. Poor prognosis could be observed despite successful cardiac surgery. There is a gap about predictors of further negative outcomes after surgical treatment. Owing to the dynamic nature of IMR, we hypothesize that multiparametric stress echocardiography (SE) would be helpful in assessing risk stratification. Aim: To evaluate the relationship between multiparametric SE parameters and outcomes after cardiac surgery in patients with IMR.

Methods

We prospectively enrolled 30 patients (62.7±8.5 yrs, 18 men), who have severe IMR by ESC classification, referred for coronary artery bypass grafting (CABG) with or without mitral surgery. Before cardiac surgery, the patients performed semi-supine bicycle multiparametric SE. Wall motion abnormalities, systolic and diastolic volumes of left ventricle, B-lines (lung congestion feature), left atrium volume, pulmonary pressure, mitral regurgitation volume, and effective regurgitation orifice area (EROA) were assessed before and during exercise. Ejection fraction (EF) and left contractile reserve were calculated. All-cause death was an endpoint.

Results

All patients had indications for CABG due to severe three-vessel disease. Before exercising, EF was 42±12%, end-diastolic volume was 167±49 ml, systolic volume of left ventricle was 86±39 ml, left atrium was 103±37 ml, global longitudinal strain was 12±4%, index of wall motion abnormality was 1.83±0.48, EROA was 0.39±0.22 cm2, regurgitation volume was 58±27 ml, systolic pulmonary pressure was 43±16 mmHg, and B-lines were 2.4±2. During exercise, EF was 44±17%, end-diastolic volume was 148±54 ml, systolic volume of left ventricle was 98±44 ml, index of wall motion abnormality was 2.30±0.49, EROA was 0.45±0.2 cm2, regurgitation volume was 70±32 ml, systolic pulmonary pressure was 51±14 mmHg, and B-lines were 5.4±3.3. A median follow-up time was 332 days (224–335). ROC analysis demonstrated that left ventricle end-diastolic volume during exercise (the cut-off value 192 ml, area under the ROC curve 0.77, p&lt;0.03), EROA during exercise (the cut-off value 0.37 cm2, the area 0.86, p&lt;0.0003), regurgitant volume during stress (the cut-off value 82 ml, the area 0.79, p&lt;0.02), the difference between stress and rest B-lines (the cut-off value 6 lines, the area 0.83, p&lt;0.0001), the difference between stress and rest EROA (the cut-off value 0.15 cm2, the area 0.77, p=0.05) were associated with death.

Conclusion

The stress echocardiographic parameters were associated with increased mortality after cardiac surgery in patients with IMR over the 1-year follow-up. B-lines (objective evidence of severe congestive heart failure), EROA, regurgitation volume (severity of mitral regurgitation during exercise) were all associated with worse outcome. These preliminary results should be confirmed in the larger studies.

Funding Acknowledgement

Type of funding sources: None.

Micropattern platform promotes extracellular matrix remodeling by human PSC-derived cardiac fibroblasts and enhances contractility of co-cultured cardiomyocytes

In native heart tissue, cardiac fibroblasts provide the structural framework of extracellular matrix (ECM) while also influencing the electrical and mechanical properties of cardiomyocytes. Recent advances in the field of stem cell differentiation have led to the availability of human pluripotent stem cell-derived cardiac fibroblasts (iPSC-CFs) in addition to cardiomyocytes (iPSC-CMs). Here we use a novel 2D in vitro micropatterned platform that provides control over ECM geometry and substrate stiffness. When cultured alone on soft micropatterned substrates, iPSC-CFs are confined to the micropatterned features and remodel the ECM into anisotropic fibers. Similar remodeling and ECM production occurs when cultured with iPSC-CMs in a co-culture model. In addition to modifications in the ECM, our results show that iPSC-CFs influence iPSC-CM function with accelerated Ca2+ transient rise-up time and greater contractile strains in the co-culture conditions compared to when iPSC-CMs are cultured alone. These combined observations highlight the important role cardiac fibroblasts play in vivo and the need for co-culture models like the one presented here to provide more representative in vitro cardiac constructs.