A53 SACCHAROMYCES BOULARDII CNCM I-745 IMPROVES ANXIETY-LIKE BEHAVIOR AND RESCUES DYSMOTILITY IN A HUMANIZED MOUSE MODEL OF IRRITABLE BOWEL SYNDROME WITH CO-MORBID ANXIETY

Background

Irritable bowel syndrome (IBS) is one of the most common conditions seen by gastroenterologists for which there is no effective cure. The pathophysiology of IBS is multifactorial and poorly understood, but the condition is characterized by chronic abdominal pain accompanied by altered bowel habits in the absence of an underlying structural abnormality. IBS is frequently associated with psychiatric co-morbidities such as anxiety and depression and has been considered a disorder of gut-brain communication. We previously developed a humanized mouse model of IBS with co-morbid anxiety (IBS+A) by colonizing germ-free mice with fecal microbiota of IBS+A patients.

Aims

To test the therapeutic potential of the probiotic yeast Saccharomyces boulardii CNCM I-745 (S. bou) in preventing the transfer of the IBS+A phenotype and investigated underlying mechanisms.

Methods

Germ-free Swiss-Webster mice were colonized with fecal microbiota from an IBS+A patient or from a healthy subject (controls) and after three weeks they were gavaged daily for two weeks with 3g/kg/day of the probiotic S. bou (Biocodex–France) or water. Behavior, intestinal motility and permeability were assessed at sacrifice. Potential mechanisms were assessed by microbiota 16S rRNA gene sequencing, gene expression by Nanostring Counter Gene Expression and indole quantification by absorption using Kovak’s reagent.

Results

IBS+A colonized mice developed 25% faster gastrointestinal transit (P<0.05) and had a 3-fold longer latency time in the step-down test (P<0.001), indicative of anxiety-like behaviour compared with controls. S. bou normalized gastrointestinal transit (P<0.05) and shortened by 50% the step-down latency (P<0.01), compared to water-treated mice. Microbiota of IBS+A colonized mice had higher abundance of Unc. Erysipelotrichaceae and Unc. Coriobacteriaceae, and lower abundance of Oscillospira, Weissela, and Fructubacillus. S. bou treatment prevented these changes and the microbiota was similar to controls. Predicted function analysis in S. bou treated mice suggested higher number of genes implicated in indole biosynthesis (P<0.05) and S. bou increased indole levels by 20% in vitro. Finally, Trpv1, a gene implicated in visceral hypersensitivity and anxiety, was increased by 2-fold in IBS+A colonized mice compared with controls (P<0.001), and this was reverted by 20% (P<0.05) by S. bou treatment.

Conclusions

Our data indicate that Saccharomyces boulardii CNCM I-745 supplementation improves the intestinal and behavioral phonotype that is induced by IBS+A microbiota in mice. Putative mechanisms include regulation of indole production by bacteria and regulation of host Trpv1 gene expression. The results prompt investigation of S. bou in IBS patients with co-morbid anxiety.

Funding Agencies

Biocodex – Gentilly – France

A122 THE INFLUENCE OF SEX AND THE GUT MICROBIOTA ON VISCERAL PAIN SENSITIVITY IN MICE

Background

Abdominal pain is a common complaint in patients with chronic gastrointestinal disorders. Its treatment is of limited efficacy as the pathophysiology is largely unknown. Accumulating evidence suggests that gut microbiota is an important determinant of gut function, including visceral sensitivity. Germ-free (GF) mice have been shown to have altered pain signaling, which normalizes after colonization. Sex also appears to play a key role in visceral sensitivity, as abdominal pain is diagnosed predominantly in female patients. Thus, both gut bacteria and sex are important in the regulation of gut nociception, but the underlying mechanisms remain poorly understood.

Aims

To investigate the role of gut microbiota and sex in abdominal pain.

Methods

We used primary cultures of sensory neurons from dorsal root ganglia (DRG) of female and male conventional mice (SPF) or germ-free (GF) mice, age 7–18 weeks. To study the visceral afferent activity in vitro, calcium mobilization in DRG sensory neurons was measured by inverted fluorescence microscope using a fluorescent calcium probe Fluo-4 (1mM). Two parameters were considered: i) percentage of responding neurons and ii) intensity of neuronal response. First, DRG sensory neurons were stimulated by a TRPV1 agonist capsaicin (12.5nM, 125nM and 1.25µM) or by an agonist mix of G-protein coupled receptors (GPCR: bradykinin, histamine and serotonin; 1µM, 10µM and 100µM). We next cultured Escherichia coli JM83 (E. coli) and Enterobacter aerogenes (E. aer) overnight in LB and LDMIIG medium, respectively. Bacterial supernatant of 1010 CFU/mL was diluted to 1% in Krebs Ringer solution to treat DRG neurons from GF/SPF mice and calcium mobilization was measured.

Results

The percentage of neurons responding to capsaicin and GPCR agonist was similar in SPF male and SPF female. In contrast, the intensity of the neuronal response was higher in SPF male compared to SPF female mice in response to capsaicin (125nM p<0.035 and 1.25µM p<0.038) but not in response to GPCR. The same trend was observed in GF mice. Neuronal activation induced by capsaicin or GPCR agonist was similar in SPF and GF mice. While bacterial supernatant from E. coli did not affect the activity of sensory neurons, the bacterial supernatant from E. aer induced changes in calcium mobilization in DRG neurons.

Conclusions

Our data suggest that at the level of DRG neurons from healthy mice, female sex and the absence of gut microbiota do not predispose to visceral hypersensitivity. In fact, the intensity of neuronal responses to capsaicin appear to be higher in DRGs from male mice. Furthermore, we show that metabolites from certain bacteria can activate sensory neurons. Thus, further studies are needed to investigate the role of gut microbiota and sex in visceral sensitivity

Funding Agencies

CIHR

Diversity and abundance of comammox bacteria in the sediments of an urban lake

AIMS

Although comammox have been discovered in a variety of ecosystems, there are few studies in urban lakes. This paper attempted to confirm whether this ammonia-oxidizing microbe exists in urban lakes and to determine the factors influencing its existence.

METHODS AND RESULTS

This study investigated the diversity and abundance of comammox bacteria in sediments of a typical urban lake in China, and their ecological relationship with other ammonia-oxidizing micro-organisms. The phylogenetic analysis indicated that comammox clade A existed in the sediment of Lake Donghu, and the comammox bacteria co-existed with ammonia-oxidizing archaea (AOA), ammonia-oxidizing bacteria (AOB) and anaerobic ammonia-oxidizing (anammox) bacteria in the sediment of this lake. The abundances of the ammonia monooxygenase subunit A (amoA) genes for comammox, AOA, AOB and anammox 16S rRNA were 2·43 × 10⁸ , 1·07 × 10⁸ , 3·24 × 10⁷ and 3·21 × 10¹¹ copies per gram dry sediment respectively. Moreover, the amoA gene abundance of comammox was positively correlated with that of AOA and AOB. The redundancy analysis showed that the abundance of the comammox amoA gene was negatively correlated with the concentration of main indicators for nitrogen status in both the sediment and the water column, indicating that eutrophication may inhibit the growth of comammox bacteria.

CONCLUSIONS

Comammox bacteria play an important ecological role in the nitrogen cycle of urban lake sediments.

SIGNIFICANCE AND IMPACT OF THE STUDY

Our results indicated comammox bacteria were widespread in urban lakes and eutrophication may inhibit their growth.

Dietary Inflammatory Index and Leukoaraiosis in Patients with Ischemic Stroke

OBJECTIVES

Diet may change the chronic levels of systemic inflammation, which in turn influence the development of leukoaraiosis (LA). This study aimed to examine the association between dietary inflammatory index (DII) and LA in patients with ischemic stroke.

METHODS

Patients with first-ever ischemic stroke were enrolled from two centers. A semi-quantitative food frequency questionnaire (FFQ) was used to evaluate diet contents. The DII score of each patient was calculated based on the reported diet contents. Presence and degree of LA were evaluated with a magnetic resonance imaging (MRI) scan. LA was graded according to Fazekas scale.

RESULTS

Of the 497 enrolled patients, 337 (67.8%) were detected with LA. Patients with LA had a higher DII score (0.23 vs -0.88, P < 0.001). Logistic regression analysis detected that patients with highest quartile of DII score had an OR of 3.61 (95% CI: 2.05-6.36, P < 0.001) for LA compared with those with lowest quartile of DII. After adjusting for major confounders, the highest DII quartile remained as an independent predictor for LA (OR = 2.66, 95% CI: 1.41-5.00, P = 0.008).

CONCLUSIONS

A pro-inflammatory diet pattern, as indicated by higher DII values, appears to be associated with a higher risk of LA. This result suggested that dietary-mediated inflammation may involved in the pathogenesis of LA, which warrant further study.

Factors associated with overall survival and relief of dysphagia in advanced esophageal cancer patients after 125I seed-loaded stent placement: a multicenter retrospective analysis

Iodine-125 (125I) seed-loaded stent placement has served as an effective palliation for malignant esophageal strictures in China. We performed a retrospective study to identify the prognostic factors of this irradiation stent placement in advanced esophageal cancer patients. A total of 201 patients who underwent 125I seed-loaded stent placement were included in this study from June 2012 to March 2016 at five hospitals in China. The Cox regression models adjusted for stratification factors were used, and a stepwise multivariate analysis was performed to predict the overall survival and relief of dysphagia on the basis of pretreatment clinical characteristics, respectively. Three independent prognostic factors were identified for overall survival: histopathological subtype (squamous cell carcinoma vs. adenocarcinoma, hazard ratio [HR] 1.45, 95% confidence interval [CI95%]: 1.01-2.09, P = 0.046), serum total protein (≥66 g/L vs. <66 g/L, HR 0.61, CI95%: 0.48-0.59, P = 0.023), and performance status (<2 vs. ≥2, HR 1.57, CI95%: 1.09-2.08, P = 0.013). Four factors were significantly associated with the relief of dysphagia: T stage (T3 vs. T4, P = 0.003), tumor location (superior vs. inferior, P = 0.049), tumor-node-metastasis classification (IV vs. II, P = 0.025), and age (≥71 years vs. <71 years, P = 0.029). Prognostic factors identified from this analysis can be used to aid clinical decision-making and design future clinical trials.

[Exploration and development of indocyanine green fluorescence applied in laparoscopic splenic hilum lymph node dissection for gastric cancer]

With the continuous development of laparoscopic techniques and the concept of individualized treatment, laparoscopic surgery is also moving from "minimally invasive" to "minimally invasive plus precision" . Lymph node metastasis is one of the most important risk factors affecting the prognosis of gastric cancer (GC). Reasonable lymph node dissection has always been an important exploration direction in the field of GC surgery. In recent years, domestic and foreign studies have found that the new tracer, indocyanine green (ICG), can detect the lymphatic vasculature non-invasively, and more accurately display the perigastric lymph nodes, providing a new perspective in laparoscopic lymph node dissection for GC. Alternatively, since the application of ICG in laparoscopic gastrointestinal tumor surgery, especially in gastric cancer surgery is still in the early stage of exploration and experience accumulation, more high-level medical evidences are needed to evaluate its clinical value.

IKBKE enhances TMZ-chemoresistance through upregulation of MGMT expression in glioblastoma

PURPOSE

Glioblastoma multiforme (GBM) is the most common and aggressive malignant type of brain tumor. Despite advances in diagnosis and therapy, the prognosis of patients with GBM has remained dismal. Multidrug resistance and high recurrence are two of the major challenges in successfully treating brain tumors. IKBKE (inhibitor of nuclear factor kappa-B kinase subunit epsilon) is a major oncogenic protein in tumors and can inhibit glioblastoma cell proliferation, migration, and tumorigenesis. Our study aimed to investigate the mechanism of IKBKE enhancing the resistance of glioma cells to temozolomide.

METHODS

For the in vitro experiments, LN18 and U118 glioblastoma cells were treated with a combination of sh/oe-IKBKE lentivirus and TMZ. Cell proliferation was determined by the EdU assay and colony formation assays. Apoptosis was analyzed by the TUNEL assay. In vivo, LN18 NC and LN18 sh-IKBKE cells were implanted into the cerebrums of nude mice to detect the effect of combination therapy. The protein and mRNA levels were assayed by western blot, immunohistochemistry, and qRT-PCR.

RESULTS

In this study, we demonstrated that IKBKE enhances the resistance of glioblastoma cells to temozolomide (TMZ) by activating the AKT/NF-κB signaling pathway to upregulate the expression of the DNA repair enzyme o6-methylguanine-dna methyltransferase (MGMT). In glioblastoma cells, IKBKE knockdown enhances apoptosis and suppresses cell proliferation, clone formation, and tumor development in vivo induced by TMZ. However, overexpression of IKBKE reduces the effects of TMZ.

CONCLUSION

Our studies suggest that inhibition of IKBKE can enhance the therapeutic effect of TMZ on GBM in vitro and in vivo, providing new research directions and therapeutic targets for the treatment of GBM.

[Efficacy of a novel fully covered radioactive stent for advanced esophageal and gastric cardia cancer: a retrospective controlled study]

Objective: To assess the feasibility, safety, and efficacy of a novel fully covered radioactive stent for the treatment of advanced esophageal and gastric cardia cancer. Methods: Data of 122 patients, who underwent esophageal radioactive stent placement for advanced esophageal or gastric cardia cancer between January 2012 and September 2017 in Zhongda Hospital, were retrospectively analyzed. Patients were divided into the novel stent group (n=59; 45 males, 14 females; mean age 73±10 years old) and the conventional stent group (n=63; 51 males, 12 females; mean age 72±9 years old), according to the types of radioactive stents. No significant difference was found between the two groups in baseline characteristics (all P>0.05). Outcomes were measured in terms of technical success, dysphagia score, stent restenosis, stent migration, major complications, and overall survival. Results: The technical success rate was 98.3% in the novel stent group, and 100.0% in the conventional stent group (P=0.484) . The dysphagia scores 3 days after surgery decreased from 3.27±0.45 and 3.37±0.49 to 1.25±0.66 and 1.32±0.50, respectively (all P<0.01), and the variances were comparable (P=0.709). Compared with conventional stents, novel stents were significantly associated with a decreased in the rate of stent restenosis, 11.9% vs 27.0%; cause-specific hazard ratio 0.387, 95%CI 0.160-0.934 (P=0.035); sub-distributional hazard ratio 0.401, 95%CI 0.167-0.963 (P=0.041), while the stent migration rate was statistically comparable (13.6% vs 6.3%, P=0.181). There was no significant difference between the novel stent group and the conventional stent group in major complications (all P>0.05), including moderate-severe chest pain (22.0% vs 25.4%), hemorrhage (11.9% vs 11.1%), fistula formation (1.7% vs 4.8%), and aspiration pneumonia (5.1% vs 6.3%). The median overall survival was 146(95%CI 115-177) days in the novel stent group, and 147(95%CI 98-196) days in the conventional stent group, and no significant difference was found (P=0.967). Conclusions: In patients with advanced esophageal or gastric cardia cancer,placement of a novel fully covered radioactive stent is safe and effective. This novel stent can relieve dysphagia rapidly and prevent stent restenosis effectively.

The therapeutic efficacy of pediatric ALL patients with MLL gene rearrangement treated with CCLG-ALL2008 protocol

OBJECTIVE

In this study, we retrospectively evaluated the therapeutic efficacy of China Children Leukemia Group-ALL2008 (CCLG-ALL 2008) protocol in pediatric patients with mixed-lineage leukaemia (MLL) gene rearrangement of acute lymphoblastic leukemia (ALL) to identify the prognostic factors.

PATIENTS AND METHODS

Six hundred and thirty-four patients with ALL were enrolled in this study between June 2008 and Dec 2014. High-risk group (HR) consisted of 217 cases, of which 28 cases were MLL related positive (first group), 22 cases were BCR/ABL positive (second group), and 167 cases were negative with MLL related or BCR/ABL (third group). The therapeutic efficacy was evaluated at the time points of day 8 (TP1), day 15 (TP2), day 33 (TP3) and 12th week (TP4) with the protocol, respectively. Overall-survival (OS) and relapse-free-survival (RFS) and treatment-related mortality (TRD) were analyzed as well.

RESULTS

The first group accounted for 4.4% of all patients. Compared with the second and third group, the first group had more cases younger than 2 years, with initial leukocytes ≥50×109/L, and poor response on TP2. Moreover, patients older than 2 years old had a good 5 years OS (84% ± 9% vs. 37% ± 20%, p<0.05) and RFS (84% ± 9% vs. 29% ± 17%, p<0.05). There were no significant differences in the recurrence rate, TRD, 5 years OS and RFS among three groups. For the first group, compared with good response to prednisone, patients with poor response to prednisone had a poor 5 years RFS (41% ± 17% vs. 81% ± 10%, p<0.05). Multivariate Cox regression analysis identified that RFS and OS were influenced by such factors as age, MLL fusion partners, and prednisone response (p<0.05).

CONCLUSIONS

Such factors as younger age than 2 years old, MLL/AF4 fusion gene, poor response to prednisone, or no complete remission (CR) on TP3 were poor prognostic parameters in predicting the outcome in childhood ALL with MLL gene rearrangement treated with CCLG-ALL 2008 protocol.

Seroma prevention strategies in laparoscopic ventral hernia repair: a systematic review

BACKGROUND

Laparoscopic ventral hernia repair (LVHR) has been increasing in popularity over the years. Seroma formation is a common complication of LVHR. The aim of this study is to review the current evidence on seroma prevention strategies following LVHR.

METHODS

A systematic search of PubMed, Embase (1946-13 February 2019) and Medline (1946-13 February 2019) databases was conducted using terms which include "seroma", "hernia, ventral" and "laparoscopy". All studies are comparative retrospective or prospective human adult studies in peer-reviewed journals describing at least one intra-operative intervention designed to decrease the rate of seroma formation in laparoscopic ventral hernia repair.

RESULTS

The database searches identified 3762 citations, and 21 studies were included for final analysis. Five studies compared the different methods of mesh fixation, nine studies compared primary defect closure (PFC) and bridged repair, two studies compared the effect of different types of meshes, two studies looked into the use of electrical cauterization, one study compared single- site laparoscopy with conventional laparoscopy, one study looked into the use of fibrin sealant and one study compared transabdominal preperitoneal placement of mesh with conventional repair. PFC appears to be the most promising with large studies showing a low rate of seroma formation with additional benefits of decreasing wound infection and recurrence rate. Cauterisation of hernia sac and injection of fibrin sealant also show promising results but are mainly derived from small studies. Other strategies did not demonstrate benefit.

CONCLUSION

Currently, primary fascial closure appears to be the most promising strategy available to decrease seroma formation after LVHR based on the results of large studies. Other promising strategies that decrease dead space such as cauterisation of the sac and fibrin sealant injection will require further multicentre trials to confirm benefit before an increase in operative time and cost can be justified for their routine use.

Effect of thermosonication process on physicochemical properties and microbial load of goat's milk

In this study, thermosonication was used as a combined treatment of raw goat milk (RGM) using pasteurization (72 °C for 15 s) and ultrasound treatments (20 kHz at the power variance of 150 W, 200 W, 300 W and 400 W for 10 min). Investigation on the impact of the microbial load, protein content, protein aggregation, the particle size of fat and casein micelles, pH, viscosity, turbidity, color, and soluble calcium and phosphorus contents were carried out, whiles RGM and PGM served as the control. Our results revealed that at 400 W, that thermosonication resulted in a significant reduction (α = 0.05) in the microbial load of the samples to less than 2.3 log cfu/mL in comparison to those of RGM and pasteurized goat milk (PGM) at 5.94 log cfu/mL and 4.76 log cfu/mL respectively. In RGM, the fat size (3.5 µm) decreased to 0.4 µm at 300 W; while those of casein micelles also decreased from 406 to 256.4 nm at 400 W. However, no significant effect was observed in the color and soluble calcium and phosphorus contents of all samples. The effect on the microbial load and fat homogenization would promote thermosonication process in the dairy industry.

Suppressed CCL2 expression inhibits the proliferation of leukemia cells via the cell cycle protein Cyclin D1: preliminary in vitro data

OBJECTIVE

Chemokine (C-C motif) ligand 2 (CCL2) is a member of the CC subfamily, which displays chemotactic activity for monocytes and basophils. This molecule plays a very important role in many solid tumors and shows changes in the bone marrow microenvironment. However, its role in acute myeloid leukaemia (AML) is still unclear.

MATERIALS AND METHODS

In this study, we established a HL-60 cell line with CCL2 knockdown to explore its effect on leukemogenesis. Lentivirus with CCL2-knockdown was successfully constructed after screening effective CCL2 short hairpin RNA (shRNA) sequences and was transfected into HL-60 cells, which was further validated at the mRNA and protein levels by real-time polymerase chain reaction (PCR) and Western blotting, respectively.

RESULTS

Low expression of CCL2 significantly decreased HL-60 cell growth by increasing the cell arrest at G1 phase by 12% more than controls. We applied RNA sequencing technology to discriminate the gene expression profiles between the cells with CCL2 knockdown and the controls, and Cyclin D1 was selected for further experiments as its expression level was significantly downregulated, which was validated at the mRNA and protein levels. Cyclin D1 knockdown experiments showed that the cell proliferation rate was evidently decelerated, and cell cycle analysis also indicated a similar pattern for CCL2.

CONCLUSIONS

Our study revealed that Cyclin D1 is an effector that mediates CCL2's function in cell proliferation by blocking cells at G1 phase.

Ptprj-as1 mediates inflammatory injury after intracerebral hemorrhage by activating NF-κB pathway

OBJECTIVE

We aimed at investigating the expression of long non-coding RNA (lncRNA) Ptprj-as1 and the role of lncRNAPtprj-as1 in inflammatory cells after intracerebral hemorrhage and its potential mechanism.

MATERIALS AND METHODS

The rat model of intracerebral hemorrhage was established. Expressions of Ptprj-as1 and inflammatory cytokines in inflammatory cells were detected by quantitative Real-time PCR (qRT-PCR). After BV2 cells were transfected with lentivirus, cell proliferation, migrative ability and apoptosis were detected by cell counting kit-8 (CCK-8) assay, transwell chamber and flow cytometry, respectively. Immunofluorescence was used to explore the ratio of M1 and M2 glial cells. The detection of tumor necrosis factor alpha (TNF-α) expression was performed using enzyme-linked immunosorbent assay (ELISA). Moreover, the expressions of key genes in NF-κB pathway were evaluated using Western blot.

RESULTS

Ptprj-as1 was highly expressed in inflammatory tissues caused by intracerebral hemorrhage (ICH). Overexpressed Ptprj-as1 promoted the migration of BV2 cells and expression levels of inflammatory cytokines such as TNF-α, interleukin-1β (IL-1β), interleukin-6 (IL-6), iNOS and NO. Meanwhile, Ptprj-as1 enhanced the proportion of M1 glial cells, the mechanism of which might be related to the activation of NF-κB pathway.

CONCLUSIONS

Ptprj-as1 activates NF-κB pathway in microglia and promotes the secretion of inflammatory cytokines, which is involved in inflammatory injury caused by intracerebral hemorrhage.

[Analyzed the related factors of VOTE score for drug-induced sleep endoscopy in patients with obstructive sleep apnea]

Objective:To analyze the related factors of VOTE score for drug-induced endoscopy（DISE） in patients with obstructive sleep apnea （OSA）. Method:Fifty-four OSA patients, diagnosed by polysomnograph, underwent surgical treatment from Nov 2014 to Dec 2016 in our hospital. All patients underwent drug induced sleep endoscope, and then the collapse of pharyngeal space was evaluated. We analyzed the related factors with VOTE score. Result:The occlusion rates were significant statistical different in different spaces of 54 OSA patients undergoing DISE（P=0.000, velum 98.15%, oropharynx 81.48%, tongue base 40.47%, and epiglottis 11.11% respectively）. The rateand of tongue base collapsing was related with Mallampatis（P<0.05） and Friedman stage（P<0.05）. The VOTE score was weakly related with Friedman stage（r=0.297, P<0.05）, medium related with BMI（r=0.376, P<0.05）, AHI（r=0.312, P<0.05） and lowest SpO2（r=0.376, P<0.01）. Conclusion:In the VOTE scoring system for DISE, the rate of collapse in tongue base was related with Mallampatis and Friedman stage. The VOTE score was medium related with BMI, AHI and Lowest SpO2, mild related with Friedman stage.

1196Transvascular pace-capture of aorticorenal ganglia provides a testable procedural endpoint for transcatheter renal artery denervation and identifies a novel therapeutic ablation target for denervation

Background

Transcatheter renal denervation procedures often produces incomplete renal denervation and inconsistent antihypertensive effect. The lack of an intraprocedural method for renal sympathetic nerve function assessment has precluded a rational and physiologically based approach to ensure adequate denervation has been achieved at the time of the procedure.

Purpose

To demonstrate that it is possible to localise aorticorenal ganglia via transvascular pacing to provide: 1) a testable procedural endpoint for transcatheter renal denervation and, 2) a novel ablation target for renal denervation.

Methods

High frequency pacing in the inferior vena cava and aorta, invasive blood pressure measurements and renal angiography was performed in sheep (N=19) to identify ARG pace-capture sites by concurrent hypertensive and renal vasoconstrictive responses. Group A (N=5) underwent ink injection labelling at the ARG pace-capture site for histological verification; Group B (N=6) received unilateral irrigated radiofrequency ablation of ARG pace-capture sites and assessment of renal innervation at 1week post-procedure; and Group C (N=8) had ARG pacing performed prior to and 2–3 weeks after unilateral transcatheter microwave renal denervation.

Results

ARG pace-capture responses were observed at paired discrete sites in the posterior IVC and anterolateral aorta approximately 40mm above the ipsilateral renal artery. Pacing elicited a mean arterial blood pressure change of 22.2 [IQR 15.5–34.3] mmHg, p<0.001, together with ipsilateral renal vasoconstriction with main renal artery calibre change of −0.42mm [IQR −0.64mm to −0.24mm] measured with quantitative coronary analysis (QCA), p<0.0001, and branch renal artery median pixel density index change −10.4% [IQR −22.7% to −3.0%], p=0.003. Contralateral renal arterial vasoconstriction was not observed consistently at either the main or branch renal artery level. Sympathetic ganglionic tissue was observed at ARG pace-capture sites, and ganglion ablation caused significant ipsilateral renal denervation with a median hilar functional sympathetic nerve area reduction of 51% [IQR 24%–52%], p=0.043, and renal cortical norepinephrine reduction of 54% [IQR 36%–59%], p=0.043. Circumferential renal denervation resulted in immediate and sustained abolition of ARP pacing induced renal vasoconstriction and significant ipsilateral renal denervation.

Conclusion

Localisation of ARG using transvascular pacing is feasible with pace-capture demonstrated by concurrent hypertensive and ipsilateral renal arterial vasoconstrictive responses. Abolition of ARG pacing induced renal arterial vasoconstriction may indicate successful renal sympathetic denervation, providing a physiological procedural endpoint to guide transcatheter renal denervation. Additionally, ablation of ARG could provide an alternative or adjunctive method for renal denervation.

Acknowledgement/Funding

University of Sydney; Western Sydney Local health District; National Health and Medical Research Council of Australia; National Heart Foundation (Au)

1197The development and validation of a novel transcatheter microwave renal denervation system

Background

Clinical studies of transcatheter radiofrequency renal denervation for treating hypertension have been hampered by the lack of consistent denervation efficacy. Microwave energy is well suited to renal denervation due to its capacity to spare vascular structures due to cooling from adjacent blood flow while enabling deep perivascular heating.

Purpose

We aimed to: 1) develop a transcatheter microwave system capable of safely delivering deep and circumferential perivascular renal nerve ablation, and 2) demonstrate the feasibility, short-term efficacy and safety of transcatheter microwave renal denervation.

Method

A novel 7F transcatheter microwave denervation system was designed, built, and iteratively prototyped in vitro and in 15 sheep. A histological grading system for microwave induced renal arterial and renal nerve injury was devised. The microwave denervation system was validated in an additional 9 sheep, which underwent unilateral renal denervation. Up to 2 microwave ablations were delivered to each artery with maximum power at 100–110W for 480s. Sheep were euthanised at 2–3 weeks post procedure. Gross microscopic histological examination as well as renal tissue norepinephrine content was analysed.

Results

Catheter deployment and ablation was successful in all 19 targeted vessel segments and ablation produced substantial circumferential perivascular injury; median ablation lesion area >395 (IQR 251–437) mm2, depth 17.1 (IQR 15.8–18.4) mm, length 16 (IQR 12–20) mm, without collateral visceral injury. Limiting power to 100W minimised arterial injury, while maintaining a deep circumferential perivascular ablation. At microwave ablation sites, a total of 292 nerve fascicles were identified, median distance from the renal artery of 4.2mm (IQR 2.1–8.8mm), of which 249 (85%) had sustained thermal injury with 128/249 (51%) showing grade 3–4 (moderate to severe) injury. Microwave denervation reduced median functional sympathetic nerve surface area at the renal hilum on anti-tyrosine hydroxylase staining by 100% (IQR 87%-100%), p=0.0039, and median renal cortical norepinephrine content by 83% (IQR 76%–92%), p=0.0078, compared to the paired control kidney.

Conclusion

Transcatheter microwave ablation can produce deep circumferential perivascular ablations over a long segment of the renal artery without significant arterial or collateral visceral injury to provide effective renal denervation. Clinical translation may enable more consistent and complete transcatheter renal denervation and antihypertensive efficacy.

Acknowledgement/Funding

University of Sydney; Western Sydney Local health District; National Health and Medical Research Council of Australia; National Heart Foundation (Au)

P834Secondary prevention medications of cardiovascular diseases in China: findings from China PEACE million persons project

Background

Cardiovascular diseases (CVD) is the leading cause of death in China. Secondary prevention medications can improve the prognosis of CVD, yet little is known about the current use, variation and associated factors of these therapies in China.

Purpose

The aim of this study was to describe the current use of secondary prevention medications among patients with established CVD in the community setting in China, assess variations across population subgroups, and identify the individual characteristics associated with these therapies.

Methods

We studied 2.6 million participants aged 35–75 years from all 31 provinces in the China Patient-Centered Evaluative Assessment of Cardiac Events (PEACE) Million Persons Project, a government-funded public health program conducted from 2014 to 2018. Participants self-reported their history of ischemic heart disease (IHD) or ischemic stroke (IS) and medication use in an interview. Among participants with IHD and/or IS, we assessed the reported use of secondary prevention medications (anti-platelet drugs and statins) in the overall population and in 1,530,408 population subgroups, defined by all possible combinations of 16 factors (age, sex, urbanity, geographic region, ethnicity, occupation, annual household income, education, marital status, medical insurance, current smoker, current drinker, history of hypertension, history of diabetes, body mass index and years since diagnosis). Multivariable mixed models with a logit link function and community-specific random intercepts were fitted to assess the associations of demographic, socioeconomic and health behavior factors with the reported use of secondary prevention mediations.

Results

Among 2,613,035 screened participants, 2.9% (74,830) had history of IHD and/or IS (1.2% for IHD, 2.4% for IS). Overall, the reported use rate either anti-platelet drugs or statins was 21.9% (18.3% anti-platelet drugs, 11.0% statins, and 7.4% both). Among the 1,530,408 population subgroups, the use of secondary prevention medications varied substantially (3.4% to 52.0%). Multivariable analyses found that that younger people, women, those living in rural areas, current smokers, current drinkers, people without hypertension or diabetes, and those with established CVD for more than 2 years were less likely to take anti-platelet drugs or statins (Figure).

Forest plot of multivariable mixed model

Conclusions

The current use of secondary prevention drugs is suboptimal and varies substantially across population subgroups in China. Our study identifies target populations for interventions to improve secondary prevention of CVD.

Acknowledgement/Funding

This study was supported by the Ministry of Finance of China and National Health Commission of China

[Application and advances in the research of animal models in burn research]

The occurrence, development, and prognosis of burn is a complicated pathophysiological process involving many organs and systems. With the development of science and technology and update of treatment concept, more and more new materials, new equipments, and new methods are applied to the diagnosis and treatment of burn. Animals similar to humans in anatomical structure and physiological function are the ideal models for research of burn. Nowadays, animal models of burn have been developed to simulate different aspects of burn. These models provide important essential support for elucidating the pathophysiological mechanism of burns and exploring new therapeutic interventions and materials for human beings. Understanding the advantages and limitations of these animal models is essential for the research of burn.

Ti n+1C n MXenes with fully saturated and thermally stable Cl terminations

MXenes are a rapidly growing family of 2D materials that exhibit a highly versatile structure and composition, allowing for significant tuning of the materials properties. These properties are, however, ultimately limited by the surface terminations, which are typically a mixture of species, including F and O that are inherent to the MXene processing. Other and robust terminations are lacking. Here, we apply high-resolution scanning transmission electron microscopy (STEM), corresponding image simulations and first-principles calculations to investigate the surface terminations on MXenes synthesized from MAX phases through Lewis acidic melts. The results show that atomic Cl terminates the synthesized MXenes, with mere residual presence of other termination species. Furthermore, in situ STEM-electron energy loss spectroscopy (EELS) heating experiments show that the Cl terminations are stable up to 750 °C. Thus, we present an attractive new termination that widely expands the MXenes' functionalization space and enables new applications.

[Rosai-Dorfman disease: a clinicopathologic analysis and whole exome sequencing in 23 cases]

目的

分析Rosai-Dorfman disease（RDD）的临床病理特征，利用全基因组外显子测序探讨RDD的发病机制。

方法

回顾性分析第二军医大学附属长海医院、长征医院2010年1月至2018年7月收治的23例RDD患者临床病理资料，并对9例患者石蜡包埋组织标本进行了全基因组外显子测序。

结果

23例RDD患者中位年龄47（10~79）岁，19例为结外型，3例为淋巴结型，1例为混合型。所有患者均接受了手术切除病灶，19例患者中位随访24（1~67）个月，均无复发。病理形态主要表现为淋巴结窦内或结外组织中组织细胞增生伴有噬淋巴细胞现象，免疫组化示组织细胞表达S100、CD68、CD163，不表达CD1a。全基因组外显子测序发现mTOR、KMT2D和NOTCH1基因突变。

结论

mTOR、KMT2D和NOTCH1基因突变可能参与了RDD的发病机制，其临床意义仍需要进一步研究。

Light-induced systemic signalling down-regulates photosynthetic performance of soybean leaves with different directional effects

When plants are exposed to a heterogeneous environment, photosynthesis of leaves is not only determined by their local condition, but also by certain signals from other parts of the same plant, termed systemic regulation. Our present study was conducted to investigate the effects of light-dependent systemic regulation on the photosynthetic performance of soybean (Glycine max L. Merr.) under heterogeneous light conditions. Soybean plants were treated with heterogeneous light. Then gas exchange characteristics were measured to evaluate the photosynthetic performance of leaves. Parameters related to photosynthetic pigments, chlorophyll fluorescence, Rubisco and photosynthates were examined to study the mechanisms of light-dependent systemic regulation on photosynthesis. Light-induced systemic signalling by illuminated leaves reduced the Pn of both upper and lower non-illuminated leaves on the same soybean plant. The decrease in gs and increase in Ci in these non-illuminated leaves indicated restriction of carbon assimilation, which was further verified by the decline in content and activity of Rubisco. However, the activation state of Rubisco decreased only in upper non-illuminated leaves. Quantum efficiency of PSII (ΦPSII) and ETR also decreased only in upper non-illuminated leaves. Moreover, the effects of light-induced systemic signalling on carbohydrate content were also detectable only in upper non-illuminated leaves. Light-induced systemic signalling by illuminated leaves restricts carbon assimilation and down-regulates photosynthetic performance of non-illuminated leaves within a soybean plant. However, effects of such systemic regulation differed when regulated in upward or downward direction.

[Retrospective study of diagnosis and treatment of renal oncocytoma]

OBJECTIVE

To summarize the experience of diagnosis and surgical treatment of renal oncocytoma, and to evaluate the surgical results based on follow-up results, in order to find the best strategy.

METHODS

In the study, 21 cases with renal oncocytoma from December 2003 to April 2016 in Peking University Third Hospital were retrospectively analyzed, including 4 males, and 17 females, with 10 cases on the right side and 11 cases on the left side. Their age was between 15 to 80 years (average: 58 years). Ultrasound or CT examination after admission was conducted. Ultrasound examination showed solid nodules. CT manifestations were solid masses with enhancement, and the tumor size was between 1.5 cm to 6.5 cm (average: 3.3 cm). Of the 21 cases, 9 were located in the middle of kidney, 7 were located in the upper pole, and 5 were located in the lower pole. After preoperative examination, according to the size and location of the tumor, laparoscopic partial nephrectomy or laparoscopic nephrectomy was performed, respectively.

RESULTS

All the operations were successful, in which 17 cases underwent laparoscopic partial nephrectomy (including 3 cases which were converted to open surgery), and 4 cases underwent laparoscopic radical nephrectomy. The operation time ranged from 75 to 274 min (mean: 144 min), and the blood loss ranged from 10 to 1 000 mL (mean: 115 mL). The postoperative hospital stay time ranged from 6 to 13 d (average: 8.2 d). The pathological results were all renal oncocytoma. In the study, 17 cases were followed up while 4 cases were lost to follow-up. The follow-up time ranged from 12 to 175 months (mean: 44 months). One case died in 20 months after operation with unknown reason, and there were no recurrence or metastasis in the other 16 cases.

CONCLUSION

Renal oncocytoma is a benign tumor with good prognosis. Enhanced CT is an effective diagnostic method in assistant examination, but it is difficult to differentiate clear cell carcinoma only from the naked eye. It is worthwhile to measure CT value at different stages of the tumor by picture archiving and communication systems (PACS), and to compare with CT value of adjacent kidney tissue may improve the diagnostic efficiency of CT. Laparoscopic surgery is an effective treatment for renal oncocytoma. We recommend laparoscopic partial nephrectomy for the patients with renal oncocytoma as the best choice if conditions permit.

[Application of machine learning models in predicting early stone-free rate after flexible ureteroscopic lithotripsy for renal stones]

OBJECTIVE

To establish predictive models based on random forest and XGBoost machine learning algorithm and to investigate their value in predicting early stone-free rate (SFR) after flexible ureteroscopic lithotripsy (fURL) in patients with renal stones.

METHODS

The clinical data of 201 patients with renal stones who underwent fURL were retrospectively investigated. According to the stone-free standard, the patients were divided into stone-free group (SF group) and stone-residual group (SR group). We compared a number of factors including patient age, body mass index (BMI), stone number, stone volume, stone density and hydronephrosis between the two groups. For low calyceal calculi, renal anatomic parameters including infundibular angle (IPA), infundibular width (IW), infundibular length (IL) and pelvic calyceal height (PCH), would be measured. We brought above potential predictive factors into random forest and XGBoost machine learning algorithm respectively to develop two predictive models. The receiver operating characteristic curve (ROC curve) was established in order to test the predictive ability of the model. Clinical data of 71 patients were collected prospectively to validate the predictive models externally.

RESULTS

In this study, 201 fURL operations were successfully completed. The one-phase early SFR was 61.2%. We built two predictive models based on random forest and XGBoost machine learning algorithm. The predictive variables' importance scores were obtained. The area under the ROC curve (AUROC) of the two predictive models for early stone clearance status prediction was 0.77. In the study, 71 test samples were used for external validation. The results showed that the total predictive accuracy, predictive specificity and predictive sensitivity of the random forest and XGBoost models were 75.7%, 82.6%, 60.0%, and 81.4%, 87.0%, 68.0%, respectively. The first four predictive variables in importance were stone volume, mean stone density, maximal stone density and BMI in both random forest and XGBoost predictive models.

CONCLUSION

The predictive models based on random forest and XGBoost machine learning algorithm can predict postoperative early stone status after fURL for renal stones accurately, which will facilitate preoperative evaluation and clinical decision-making. Stone volume, mean stone density, maximal stone density and BMI may be the important predictive factors affecting early SFR after fURL for renal stones.

[Impact of diagnostic ureteroscopy and biopsy on radical nephroureterectomy of upper tract urothelial carcinoma]

OBJECTIVE

To investigate the impact of preoperative diagnostic ureteroscopy and biopsy (UB) on radical nephroureterectomy (RNU) and the prognosis of upper tract urothelial carcinoma (UTUC).

METHODS

The clinical data of UTUC patients receiving RNU between Jan. 2007 and Dec. 2016 were retrospectively collected. The median follow up time was 40 months. The operation time and blood loss of RNU were compared between UB group and non-UB group. Subgroup analyses were conducted according to the time interval between UB and RNU, and surgery methods of lower ureter. The linear regression model was used to adjust for other common factors that impacted operation time.

RESULTS

A total of 163 UTUC patients were included in the final analysis. For the lower ureter, open ureterectomies were performed in 91 patients (55.9%), while retroperitoneal laparoscopic ureterectomies were performed in 72 patients (44.1%). A total of 110 (67.5%) patients received preoperative UB. Compared with non-UB group, the average operation time of UB group was significantly longer [(252.5±79.8) min vs. (221.3±79.8) min, P=0.019], but no difference of blood loss was found (median, 50 mL vs. 50 mL, P=0.143). In subgroup analysis, the average operation time of RNU was significantly prolonged when RNU was performed after 1 week of UB (P=0.023). Meanwhile, the median blood loss of RNU increased significantly when it was done after 2 weeks of UB compared with non-UB group (100 mL vs. 50 mL, P=0.012). UB was also significantly prolonged the operation time of RNU in retroperitoneal laparoscopic ureterectomy group (P=0.012). In multivariable analysis, UB (P=0.049), ≥pT3 (P=0.039), pN+ (P=0.018) and ureterectomy method (P=0.005) were independent risk factors of prolonged operation time. The 3-year cancer specific survival (CSS) rate was 87.2% in our cohort. UB had no significant impact on cancer specific survival (P=0.435).

CONCLUSION

UB was an independent risk factor of prolonged RNU time, but did not significantly influence cancer specific survival of upper tract urothelial carcinoma patients.

[Application of U-shaped convolutional neural network in auto segmentation and reconstruction of 3D prostate model in laparoscopic prostatectomy navigation]

OBJECTIVE

To investigate the efficacy of intraoperative cognitive navigation on laparoscopic radical prostatectomy using 3D prostatic models created by U-shaped convolutional neural network (U-net) and reconstructed through Medical Image Interaction Tool Kit (MITK) platform.

METHODS

A total of 5 000 pieces of prostate cancer magnetic resonance (MR) imaging discovery sets with manual annotations were used to train a modified U-net, and a set of clinically demand-oriented, stable and efficient full convolutional neural network algorithm was constructed. The MR images were cropped and segmented automatically by using modified U-net, and the segmentation data were automatically reconstructed using MITK platform according to our own protocols. The modeling data were output as STL format, and the prostate models were simultaneously displayed on an android tablet during the operation to help achieving cognitive navigation.

RESULTS

Based on original U-net architecture, we established a modified U-net from a 201-case MR imaging training set. The network performance was tested and compared with human segmentations and other segmentation networks by using one certain testing data set. Auto segmentation of multi-structures (such as prostate, prostate tumors, seminal vesicles, rectus, neurovascular bundles and dorsal venous complex) were successfully achieved. Secondary automatic 3D reconstruction had been carried out through MITK platform. During the surgery, 3D models of prostatic area were simultaneously displayed on an android tablet, and the cognitive navigation was successfully achieved. Intra-operation organ visualization demonstrated the structural relationships among the key structures in great detail and the degree of tumor invasion was visualized directly.

CONCLUSION

The modified U-net was able to achieve automatic segmentations of important structures of prostate area. Secondary 3D model reconstruction and demonstration could provide intraoperative visualization of vital structures of prostate area, which could help achieve cognitive fusion navigation for surgeons. The application of these techniques could finally reduce positive surgical margin rates, and may improve the efficacy and oncological outcomes of laparoscopic prostatectomy.

FPR2 enhances colorectal cancer progression by promoting EMT process

Formyl peptide receptor-2 (FPR2) has been shown to promote various tumors, but its role in colorectal cancer (CRC) has not been clearly illuminated. The aim of this study was to investigate the effect of FPR2 interference on cell proliferation, migration, invasion, apoptosis, pro-angiogenesis of CRC cells, and also the mechanisms involved. Quantitative PCR assays were applied to assess the expression levels of FPR2 in CRC tissues. CRC cell line SW1116 was chosen to perform this study. We knocked down FPR2 gene by sh-RNA. Then, the cell proliferation was assayed by soft agar colony formation assay, the cell migration capacity was checked by wound healing assay, and cell invasion ability was detected by transwell assay. In addition, flow cytometric analysis was used to detect apoptosis, while endothelial tube formation assay was used to evaluate the effects of FPR2 on pro-angiogenesis in vitro. Tumorigenesis experiment in vivo was performed in nude mice. EMT-related proteins were studied by western blotting. Quantitative PCR demonstrated that FPR2 mRNA was highly expressed in the colorectal cancer tissues. SW1116 cells' capacities of proliferation, migration, invasion, anti-apoptosis and pro-angiogenesis were distinctly suppressed after silencing FPR2 in SW1116 by sh-RNA. Suppression FPR2 mRNA in SW1116 cells suppressed tumorigenicity in nude mice. The expression of proteins related to epithelial-mesenchymal transition (EMT) such as E-cadherin, N-cadherin, Snail, Slug and vimentin was changed after suppressing FPR2. In conclusion, our study demonstrated that FPR2 could promote CRC cells progression in vitro and in vivo that may relate to promoting EMT.