Activation of the CD200/CD200R1 axis improves cognitive impairment by enhancing hippocampal neurogenesis via suppression of M1 microglial polarization and neuroinflammation in hypoxic-ischemic neonatal rats

Following hypoxic-ischemic brain damage (HIBD), there is a decline in cognitive function; however, there are no effective treatment strategies for this condition in neonates. This study aimed to evaluate the role of the cluster of differentiation 200 (CD200)/CD200R1 axis in cognitive function following HIBD using an established model of HIBD in postnatal day 7 rats. Western blotting analysis was conducted to evaluate the protein expression levels of CD200, CD200R1, proteins associated with the PI3K/Akt-NF-κB pathway, and inflammatory factors such as TNF-α, IL-1β, and IL-6 in the hippocampus. Additionally, double-immunofluorescence labeling was utilized to evaluate M1 microglial polarization and neurogenesis in the hippocampus. To assess the learning and memory function of the experimental rats, the Morris water maze (MWM) test was conducted. HIBDleads to a decrease in the expression of CD200 and CD200R1 proteins in the neonatal rat hippocampus, while simultaneously increasing the expression of TNF-α, IL-6, and IL-1β proteins, ultimately resulting in cognitive impairment. The administration of CD200Fc, a fusion protein of CD200, was found to enhance the expression of p-PI3K and p-Akt, but reduce the expression of p-NF-κB. Additionally, CD200Fc inhibited M1 polarization of microglia, reduced neuroinflammation, improved hippocampal neurogenesis, and mitigated cognitive impairment caused by HIBD in neonatal rats. In contrast, blocking the interaction between CD200 and CD200R1 with the anti-CD200R1 antibody (CD200R1 Ab) exerted the opposite effect. Furthermore, the PI3K specific activator, 740Y-P, significantly increased the expression of p-PI3K and p-Akt, but reduced p-NF-κB expression. It also inhibited M1 polarization of microglia, reduced neuroinflammation, and improved hippocampal neurogenesis and cognitive function in neonatal rats with HIBD. Our findings illustrate that activation of the CD200/CD200R1 axis inhibits the NF-κB-mediated M1 polarization of microglia to improve HIBD-induced cognitive impairment and hippocampal neurogenesis disorder via the PI3K/Akt signaling pathway.

N6-methyladenosine demethylase FTO regulates synaptic and cognitive impairment by destabilizing PTEN mRNA in hypoxic-ischemic neonatal rats

Hypoxic-ischemic brain damage (HIBD) can result in significant global rates of neonatal death or permanent neurological disability. N6-methyladenosine (m6A) modification of RNA influences fundamental aspects of RNA metabolism, and m6A dysregulation is implicated in various neurological diseases. However, the biological roles and clinical significance of m6A in HIBD remain unclear. We currently evaluated the effect of HIBD on cerebral m6A methylation in RNAs in neonatal rats. The m6A dot blot assay showed a global augmentation in RNA m6A methylation post-HI. Herein, we also report on demethylase FTO, which is markedly downregulated in the hippocampus and is the main factor involved with aberrant m6A modification following HI. By conducting a comprehensive analysis of RNA-seq data and m6A microarray results, we found that transcripts with m6A modifications were more highly expressed overall than transcripts without m6A modifications. The overexpression of FTO resulted in the promotion of Akt/mTOR pathway hyperactivation, while simultaneously inhibiting autophagic function. This is carried out by the demethylation activity of FTO, which selectively demethylates transcripts of phosphatase and tensin homolog (PTEN), thus promoting its degradation and reduced protein expression after HI. Moreover, the synaptic and neurocognitive disorders induced by HI were effectively reversed through the overexpression of FTO in the hippocampus. Cumulatively, these findings demonstrate the functional importance of FTO-dependent hippocampal m6A methylome in cognitive function and provides novel mechanistic insights into the therapeutic potentials of FTO in neonatal HIBD.

Activation of the CD200/CD200R1 axis attenuates neuroinflammation and improves postoperative cognitive dysfunction via the PI3K/Akt/NF-κB signaling pathway in aged mice

BACKGROUND

Postoperative cognitive dysfunction (POCD) is a neurological complication occurring after anesthesia and surgery. Neuroinflammation plays a critical role in the pathogenesis of POCD, and the activation of the cluster of differentiation 200 (CD200)/CD200R1 axis improves neurological recovery in various neurological disorders by modulating inflammation. The aim of this study was to investigate the impact and underlying mechanism of CD200/CD200R1 axis on POCD in aged mice.

METHODS

The model of POCD was established in aged mice. To assess the learning and memory abilities of model mice, the Morris water maze test was implemented. CD200Fc (CD200 fusion protein), CD200R1 Ab (anti-CD200R1 antibody), and 740Y-P (a specific PI3K activator) were used to evaluate the effects of the CD200/CD200R1/PI3K/Akt/NF-κB signaling pathway on hippocampal microglial polarization, neuroinflammation, synaptic activity, and cognition in mice.

RESULTS

It was observed that anesthesia/surgery induced cognitive decline in aged mice, increased the levels of tumor necrosis factor alpha (TNF-α), interleukin (IL)-6, IL-1 β and decreased the levels of postsynaptic density protein 95 (PSD-95), synaptophysin (SYN) in the hippocampus. Moreover, CD200Fc and 740Y-P attenuated neuroinflammation and synaptic deficits and reversed cognitive impairment via the phosphatidylinositol 3-kinase (PI3K)/ protein kinase B (Akt)/nuclear factor-kappa B (NF-κB) signaling pathway, whereas CD200R1 Ab administration exerted the opposite effects. Our results further show that the CD200/CD200R1 axis modulates M1/M2 polarization in hippocampal microglia via the PI3K/Akt/NF-κB signaling pathway.

CONCLUSIONS

Our findings indicate that the activation of the CD200/CD200R1 axis reduces neuroinflammation, synaptic deficits, and cognitive impairment in the hippocampus of aged mice by regulating microglial M1/M2 polarization via the PI3K/Akt/NF-κB signaling pathway.

Effect of ultrasound-guided femoral nerve block with dexmedetomidine and ropivacaine on postoperative analgesia in patients undergoing total knee arthroplasty: a randomized controlled trial

Background

Dexmedetomidine, a potent and highly selective α2-adrenoreceptor agonist, has become a popular adjuvant to local anesthetics. This study was designed to investigate the effect of dexmedetomidine with ropivacaine for femoral nerve block on postoperative analgesia after total knee arthroplasty.

Methods

Forty-six patients after total knee arthroplasty received ultrasound-guided femoral nerve block with either 0.3% ropivacaine alone (group R) or 0.3% ropivacaine with 0.5 μg/kg dexmedetomidine (group RD). Total 24-h sufentanil consumption, visual analogue scale (VAS) pain scores, frequency of patient-controlled analgesia (PCA) pressed, Ramsay sedation score, the incidence of bradycardia and hypotension, and incidence of postoperative nausea and vomiting (PONV) were recorded.

Results

Compared to group R, the total 24-h sufentanil consumption was significantly reduced (110.76 ± 11.56 vs. 99.09 ± 13.31; P<0.05), the VAS scores were lower at 10 and 12 h postoperatively [3(2-3) vs. 2(1-2) and 3(2-3) vs. 2(1-3), respectively; P<0.05], the frequency of PCA pressed was lower at 8-12 and 12-16-h time intervals [(5(3-6) vs. 2(1-3) and 4(3-4) vs. 2(1-3), respectively; P<0.05]. However, there were no differences in Ramsay's sedation score and the incidence of PONV. Also, no patient experienced bradycardia and hypotension.

Conclusions

0.5 μg/kg dexmedetomidine with 0.3% ropivacaine for femoral nerve block significantly decreased the total 24-h sufentanil consumption, prolonged and enhanced the analgesic efficacy of ropivacaine, without clinically relevant cardiovascular depression or over-sedation in patients undergoing total knee arthroplasty.

Dexmedetomidine Regulates Autophagy via the AMPK/mTOR Pathway to Improve SH-SY5Y-APP Cell Damage Induced by High Glucose

Neurodegenerative diseases and postoperative cognitive dysfunction involve the accumulation of β-amyloid peptide (Aβ). High glucose can inhibit autophagy, which facilitates intracellular Aβ clearance. The α2-adrenoreceptor agonist dexmedetomidine (DEX) can provide neuroprotection against several neurological diseases; however, the mechanism remains unclear. This study investigated whether DEX regulated autophagy via the AMPK/mTOR pathway to improve high glucose-induced neurotoxicity in SH-SY5Y/APP695 cells. SH-SY5Y/APP695 cells were cultured with high glucose with/without DEX. To examine the role of autophagy, the autophagy activator rapamycin (RAPA) and autophagy inhibitor 3-methyladenine (3-MA) were used. The selective AMPK inhibitor compound C was used to investigate the involvement of the AMPK pathway. Cell viability and apoptosis were examined by CCK-8 and annexin V-FITC/PI flow cytometric assays, respectively. Autophagy was analyzed by monodansylcadaverine staining of autophagic vacuoles. Autophagy- and apoptosis-related protein expression and the phosphorylation levels of AMPK/mTOR pathway molecules were quantified by western blotting. DEX pretreatment significantly suppressed high glucose-induced neurotoxicity in SH-SY5Y/APP695 cells, as evidenced by the enhanced viability, restoration of cellular morphology, and reduction in apoptotic cells. Furthermore, RAPA had a protective effect similar to that of DEX, but 3-MA eliminated the protective effect of DEX by promoting mTOR activation. Moreover, the AMPK/mTOR pathway was involved in DEX-mediated autophagy. Compound C significantly suppressed autophagy and reversed the protective effect of DEX against high glucose in SH-SY5Y/APP695 cells. Our findings demonstrated that DEX protected SH-SY5Y/APP695 cells against high glucose-induced neurotoxicity by upregulating autophagy through the AMPK/mTOR pathway, suggesting a role of DEX in treating POCD in diabetic patients.

[Knockdown of ACC1 promotes migration of esophageal cancer cell]

Objective: To investigate the effect of acetyl-CoA carboxylase 1 (ACC1) knockdown on the migration of esophageal squamous cell carcinoma (ESCC) KYSE-450 cell and underlying mechanism. Methods: Lentiviral transfection was conducted to establish sh-NC control cell and ACC1 knocking down cell (sh-ACC1). Human siRNA HSP27 and control were transfected by Lipo2000 to get si-HSP27 and si-NC. The selective acetyltransferase P300/CBP inhibitor C646 was used to inhibit histone acetylation and DMSO was used as vehicle control. Transwell assay was performed to detect cell migration. The expression of HSP27 mRNA was examined by reverse transcription-quantitative real-time polymerase chain reaction (RT-qPCR) and the expressions of ACC1, H3K9ac, HSP27 and epithelial-mesenchymal transition-related proteins E-cadherin and Vimentin were detected by western blot. Results: The expression level of ACC1 in sh-NC group was higher than that in sh-ACC1 group (P<0.01). The number of cell migration in sh-NC group was (159.00±24.38), lower than (361.80±26.81) in sh-ACC1 group (P<0.01). The protein expression levels of E-cadherin and Vimentin in sh-NC group were statistically significant compared with sh-AAC1 group (P<0.05). The migrated cell number in sh-NC+ si-NC group was (189.20±16.02), lower than (371.60±38.40) in sh-ACC1+ si-NC group (P<0.01). The migrated cell number in sh-NC+ si-NC group was higher than that in sh-NC+ si-HSP27 group (152.40±24.30, P<0.01), and the migrated cell number in sh-ACC1+ si-NC group was higher than that in sh-ACC1+ si-HSP27 group (P<0.01). The protein expression levels of E-cadherin and Vimentin in sh-NC+ si-NC group were significantly different from those in sh-ACC1+ si-NC and sh-NC+ si-HSP27 groups (P<0.01). The protein expression levels of E-cadherin and Vimentin in sh-ACC1+ si-NC group were significantly different from those in sh-ACC1+ si-HSP27 group (P<0.01). After 24 h treatment with C646 at 20 μmmo/L, the migrated cell number in sh-NC+ DMSO group was (190.80±11.95), lower than (395.80±17.10) in sh-ACC1+ DMSO group (P<0.01). The migrated cell number in sh-NC+ DMSO group was lower than that in sh-NC+ C646 group (256.20±23.32, P<0.01). The migrated cell number in sh-ACC1+ DMSO group was higher than that in sh-ACC1+ C646 group (87.80±11.23, P<0.01). The protein expressions of H3K9ac, HSP27, E-cadherin and Vimentin in sh-NC+ DMSO group were significantly different from those in sh-ACC1+ DMSO group and sh-NC+ C646 group (P<0.01). The protein expression levels of H3K9ac, HSP27, E-cadherin and Vimentin in sh-ACC1+ DMSO group were significantly different from those in sh-ACC1+ C646 group (P<0.01). Conclusion: Knockdown of ACC1 promotes the migration of KYSE-450 cell by up-regulating HSP27 and increasing histone acetylation.

A122 MINIMALLY INVASIVE ENDOSCOPIC RESECTION TECHNIQUES FOR ANORECTAL JUNCTION NEOPLASIA: A SYSTEMATIC REVIEW AND META-ANALYSIS

Background

The management of neoplastic lesions at the anorectal junction remains debated. Endoscopic submucosal dissection (ESD) and endoscopic mucosal resection (EMR) have emerged as the primary endoscopic modalities of choice.

Purpose

We sought to compare the performance of ESD and EMR in resection of anorectal neoplasia.

Method

Two authors independently searched MEDLINE, EMBASE and Cochrane Libraries (Jan 2000 – Aug 2021) for citations evaluating the performance of endoscopic resection techniques (ESD, EMR) for lesions involving the anorectal junction (defined as within 20mm of the dentate line). The frequencies and 95% confidence intervals (95% CI) of technical success (complete removal of all neoplastic tissue at index procedure), clinically significant post-endoscopic resection bleeding (CSPEB), delayed perforation, recurrence and referral to surgery were assessed using random-effects modelling.

Result(s)

We included 11 studies (total 563 patients: 414 ESD, 149 EMR) of which nine were ESD and two were EMR studies. Technical success was achieved in 97.2% overall (95% CI 94.8%-98.5%, ESD 97.5% and EMR range 93.9%-98.0%). Clinically significant post-endoscopic resection bleeding occurred in 4.3% (95% CI 1.6%-11.1%, ESD 3.0% and EMR range 8.2%-11.0%). Delayed perforation was not identified. Recurrence at first screening colonoscopy occurred in 4.8% (95% CI 1.9%-11.7%, ESD 3.0% and EMR range 15.4%-18.4%). Referral to surgery for any reason occurred in 5.9% (95% CI 4.3%-8.0%, ESD 6.9%, EMR range 2.0%-3.0%).

Conclusion(s)

ESD and EMR demonstrate high frequencies of technical success but may have different rates of adverse events and recurrence. More studies investigating lesions at the anorectal junction should be conducted including head-to-head analyses between ESD and EMR for low-risk anorectal junction neoplasia.

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None

Disclosure of Interest

None Declared

Comparison of two probiotics in follow-on formula: Bifidobacterium animalis subsp. lactis HN019 reduced upper respiratory tract infections in Chinese infants

A randomised, double-blind, placebo-controlled trial was performed to investigate the health benefits of probiotic bacteria in infants when delivered in a follow-on infant formula. The study was conducted in Fuyang (Anhui Province, China) during winter and enrolled 192 healthy infants aged six to 12 months. Infants received one of three follow-on formulae daily for 12 weeks: supplemented with 106 cfu/g Bifidobacterium animalis subsp. lactis HN019 (n=64); 106 cfu/g Lacticaseibacillus rhamnosus HN001 (n=64); or without added probiotics (n=64). The primary endpoint was physician-confirmed bacterial or viral infections during the treatment period. Secondary endpoints included parentally reported (confirmed and unconfirmed) infections; antiviral or antibiotic treatments, and hospitalisation; stool frequency and consistency; infant growth; infant temperament; and adverse events. There were 8 cases of confirmed infection, all upper respiratory tract infections (URTIs). Confirmed URTIs were observed in 9.4% of the control group, compared to 3.1% in the HN001 group (P=0.273), and 0.0% in the HN019 group (P=0.028). A similar trend was observed for parentally reported URTIs, with 25.0% in the control group, compared with 14.1% in the HN001 group (P=0.119) and 9.4% in the HN019 group (P=0.019). No infants in the HN019 group were prescribed antibiotics or antivirals, compared with 3 (4.7%) in the HN001 group and 7 (10.9%) in the control group. No infants required hospitalisation. The probiotic-containing formulae were well-tolerated: there were no cases of diarrhoea or differences in stool frequency or characteristics, no differences in infant growth or temperament, and no treatment-related adverse events. This study directly compared the benefits of two different probiotics when added to follow-on infant formula at 106 cfu/g and consumed over a 12-week period. While HN001 showed trends toward reduced infections, HN019 showed better performance in terms of significantly reduced incidence of both physician-confirmed and parentally reported URTIs, and antibiotic/antiviral use compared to a control in Chinese infants. The trial is registered at ClinicalTrials.gov (NCT01724203).

Effect of Ultrasound-Guided Fascia Iliac Compartment Block with Nalbuphine and Ropivacaine on Preoperative Pain in Older Patients with Hip Fractures: A Multicenter, Triple-Blinded, Randomized, Controlled Trial

INTRODUCTION

Pain management for older patients with hip fractures is challenging. This study aimed to investigate the effect of ultrasound-guided fascia iliac compartment block (UGFICB) using different doses of nalbuphine in combination with ropivacaine on preoperative analgesia in older patients with hip fractures.

METHODS

In this multicenter randomized controlled trial, 280 elderly patients with hip fracture were randomly allocated into four UGFICB groups (n = 70 in each group): a ropivacaine group (30 mL 0.1% ropivacaine + 0.9% normal saline) and three ropivacaine plus nalbuphine groups (5, 10, and 20 mg nalbuphine, respectively). The primary outcomes were the duration of analgesia at rest and on passive movement. Secondary outcomes included sensory block area, side effects, and vital signs. The doses of rescue analgesia with parecoxib sodium were also analyzed.

RESULTS

The addition of nalbuphine dose-dependently increased the duration of analgesia at rest and on passive movement (P < 0.05) and expanded the area of sensory block (P < 0.05). Compared with the ropivacaine group, the pain scores at rest and on movement at 6 and 8 h after the block were lower in three ropivacaine plus nalbuphine groups (P < 0.05), without between-group differences at 2, 4, and 12 h. The four groups had comparable side effects (nausea and vomiting) and vital signs (P > 0.05).

CONCLUSIONS

UGFICB with 5, 10, and 20 mg nalbuphine added to ropivacaine prolonged the analgesia duration, increased sensory block area, reduced pain, and decreased the doses of rescue parecoxib sodium for older patients after hip fracture, without obvious side effects. Among these three doses, nalbuphine 20 mg in combination with ropivacaine provided the longest duration of analgesia and the largest sensory block area.

TRIAL REGISTRATION

Chinese Clinical Trial Registry (ChiCTR2000029934).

Dexmedetomidine alleviates olfactory cognitive dysfunction by promoting neurogenesis in the subventricular zone of hypoxic-ischemic neonatal rats

Background: Hypoxic-ischemic brain damage (HIBD) is the main cause of neurological dysfunction in neonates. Olfactory cognitive function is important for feeding, the ability to detect hazardous situations and social relationships. However, only a few studies have investigated olfactory cognitive dysfunction in neonates with HIBD; furthermore, the specific mechanisms involved are yet to be elucidated. It has been reported that neurogenesis in the subventricular zone (SVZ) is linked to olfactory cognitive function. Recently, dexmedetomidine (DEX) has been shown to provide neuroprotection in neonates following HIBD. In the present study, we investigated whether DEX could improve olfactory cognitive dysfunction in neonatal rats following HIBD and attempted to determine the underlying mechanisms.

Methods: We induced HIBD in rats using the Rice–Vannucci model, and DEX (25 μg/kg, i.p.) was administered immediately after the induction of HIBD. Next, we used triphenyl tetrazolium chloride (TTC) staining and the Zea-longa score to assess the success of modelling. The levels of BDNF, TNF-α, IL-1β and IL-6 were determined by western blotting. Immunofluorescence staining was used to detect microglial activation and microglial M1/M2 polarization as well as to evaluate the extent of neurogenesis in the SVZ. To evaluate the olfactory cognitive function, the rats in each group were raised until post-natal days 28–35; then, we performed the buried food test and the olfactory memory test.

Results: Analysis showed that HIBD induced significant brain infarction, neurological deficits, and olfactory cognitive dysfunction. Furthermore, we found that DEX treatment significantly improved olfactory cognitive dysfunction in rat pups with HIBD. DEX treatment also increased the number of newly formed neuroblasts (BrdU/DCX) and neurons (BrdU/NeuN) in the SVZ by increasing the expression of BDNF in rat pups with HIBD. Furthermore, analysis showed that the neurogenic effects of DEX were possibly related to the inhibition of inflammation and the promotion of M1 to M2 conversion in the microglia.

Conclusion: Based on the present findings, DEX treatment could improve olfactory cognitive dysfunction in neonatal rats with HIBD by promoting neurogenesis in the SVZ and enhancing the expression of BDNF in the microglia. It was possible associated that DEX inhibited neuroinflammation and promoted M1 to M2 conversion in the microglia.

Visible-Light-Promoted Desulfurative Alkylation of Alkyl Thianthrenium Salts with Activated Olefins

Reactions involving an alkyl radical generated from a primary alcohol by photochemistry are rare and challenging. Herein, we present a photocatalyst- and metal-free approach that enables the generation of an alkyl radical from the corresponding alcohol and the subsequent C(sp³)-C(sp³) bond formation with activated olefin, via an alkyl thianthrenium salt/Hantzsch ester electron donor-acceptor complex. This protocol for the conversion of a C-OH bond to a C-C bond is highly functionality tolerant and can successfully be used in late-stage functionalization of pharmaceuticals.

[Exploring the effects of entecavir treatment on the degree of liver fibrosis in patients with non-alcoholic fatty liver combined with chronic hepatitis B in Tibet region]

Objective: To explore the efficacy of entecavir antiviral therapy on the degree of liver fibrosis in patients with non-alcoholic fatty liver disease (NAFLD) combined with chronic hepatitis B (CHB) in Tibet region. Methods: HBeAg-positive CHB patients who were treated with entecavir in the outpatient and inpatient Department of Infectious Diseases of the Tibet Autonomous Region people's Hospital between January 2018 to December 2019 were retrospectively analyzed. Among the 140 subjects with CHB, 95 cases were CHB alone, and the other 45 cases were diagnosed as CHB combined with NAFLD by ultrasound. All patients were given entecavir 0.5 mg orally once daily on an empty stomach for 48 weeks. HBeAg negative conversion rate, blood glucose, blood lipid, liver function and the degree of liver fibrosis were compared between the two groups at the 12th, 24th and 48th weeks of treatment to evaluate the virological response. SPSS 19.0 statistical software was used to process the data. Measurement data were expressed as mean ± standard deviation (x¯±s). Descriptive statistical analysis was used for t-test, and the categorical variables were expressed as percentage (%) and χ² test. A p-value < 0.05 was considered as statistically significant. Results: After 48 weeks of treatment, the HBeAg and HBV DNA negative conversion rate were significantly better in patients with CHB alone (group B) than CHB combined with NAFLD (group A), that is to say, HBeAg negative conversion rate in group A and B patients were 28.90% and 40%, respectively, and group B was better than group A. HBV DNA negative conversion rate was significantly elevated in group B (83.2%) than group A (64.4%), with statistical significance (P<0.05), and the difference between the both groups was statistically significant. Alanine aminotransferase level was significantly decreased in patients with CHB alone than patients with CHB combined with NAFLD. Aspartate aminotransferase/platelet ratio index was significantly decreased after treatment than before treatment in both group of patients, and the depletion was more pronounced in CHB alone group. Liver stiffness values were significantly decreased in patients with CHB combined with NAFLD than CHB alone group. Moreover, liver stiffness values was higher in group A than group B before treatment under the influence of fat attenuation factors, and the differences before treatment and after treatment were 3.50±4.66 and 2.05±2.53, respectively; however, group B was not affected by fat attenuation factors, so LSM value reduction in group A was more obvious, and the differences were statistically significant. There was no statistically significant difference in blood glucose and blood lipids levels before and after treatment between the two groups. Conclusion: NAFLD has a certain effect on antiviral therapy and liver fibrosis in patients with CHB, i.e., the effect of antiviral therapy in patients with CHB alone is better than patients with CHB combined with NAFLD. Patients with CHB combined with NAFLD when treated with antiviral therapy had a significantly greater degree of liver stiffness reduction than patients with CHB alone. Therefore, it is necessary to actively intervene the risk factors associated with NAFLD according to the actual situation of different individuals to improve clinical efficacy of antiviral therapy.

A105 ENDOSCOPIC MUCOSAL RESECTION AND ENDOSCOPIC SUBMUCOSAL DISSECTION FOR ILEOCECAL VALVE NEOPLASIA: A SYSTEMATIC REVIEW AND META-ANALYSIS

Background

Neoplastic lesions at the ileocecal valve (ICV) represent a complex lesion subgroup given the unique anatomical characteristics of this location. Both endoscopic mucosal resection (EMR) and endoscopic submucosal dissection (ESD) are established techniques for colorectal neoplasia but comparative analyses for ICV lesions are lacking.

Aims

Evaluate the performance of EMR and ESD for ICV neoplasia.

Methods

Between Jan 2000 to Aug 2021, two authors independently searched MEDLINE, EMBASE and Cochrane Libraries for relevant citations evaluating the performance of either EMR and/or ESD for ICV neoplasia; defined as lesions involving at least one component of the ICV complex. The rate of technical success (complete removal of all neoplastic tissue during index procedure of those lesions deemed amenable to endoscopic resection), clinically significant post-endoscopic resection bleeding (CSPEB), delayed perforation, and recurrence were assessed. Meta-analysis was performed using a random-effects model.

Results

Nine studies (367 patients, 252 EMR, 115 ESD) were included in the analysis. Successful removal of all visible neoplastic tissue of those deemed amenable to endoscopic resection was 98.1% (EMR 99.6%, ESD 97.4%). Of note, only 2 studies, both assessing EMR, provided data on lesions which were not considered for endoscopic resection ranging from 5.6–23.7%. Average procedure time ranged from 45–49 minutes for EMR and 52–191 minutes for ESD. Clinically significant post-endoscopic resection bleeding occurred in 6.2% (EMR 9.4%, ESD 4.4%). Delayed perforation occurred in 0.6% (EMR 0.4%, ESD 2.0%). Recurrence occurred in 3.1% (EMR 13.2%, ESD 1.9%).

Conclusions

Endoscopic resection, both with EMR and ESD, demonstrates high technical success and good adverse event profiles amongst ICV neoplasia deemed amenable for endoscopic resection.

Funding Agencies

None

A123 MINIMALLY INVASIVE ENDOSCOPIC RESECTION TECHNIQUE PERFORMANCE FOR PERI-APPENDICEAL COLORECTAL NEOPLASIA: A SYSTEMATIC REVIEW AND META-ANALYSIS

Background

Minimally invasive endoscopic resection techniques, including endoscopic mucosal resection (EMR), endoscopic submucosal dissection (ESD) and endoscopic full-thickness resection (EFTR) have revolutionized the management of peri-appendiceal colorectal neoplasia. However, questions remain about their comparative performance.

Aims

We sought to evaluate the performance of EMR, ESD and EFTR for peri-appendiceal colorectal neoplasia.

Methods

Two authors independently searched MEDLINE, EMBASE and Cochrane Libraries (Jan 2000 – Aug 2021) for citations evaluating the performance of endoscopic resection techniques (EMR, ESD, EFTR) for peri-appendiceal colorectal neoplasia (defined as those involving or in close proximity to the appendiceal orifice). The incidence rates and 95% confidence intervals (95% CI) of technical success (complete removal of all neoplastic tissue at index procedure), clinically significant post-endoscopic resection bleeding (CSPEB), delayed perforation, recurrence and referral to surgery were assessed using random-effects modelling.

Results

12 studies were included in the analysis (479 patients: 185 EMR, 171 ESD, 123 EFTR). Technical success was achieved in 93.5% (95% CI 90.9%-95.4%, EMR 93.5%, ESD 94.1%, EFTR 92.7%). Clinically significant post-endoscopic resection bleeding occurred in 1.3% (95% CI 0.4%-4.3%, EMR 3.8%, ESD 1.2%, EFTR 0%). Delayed perforation occurred in 1.9% (95% CI 0.9%-3.9%, EMR 0%, ESD 2.4%, EFTR 2.4%). Recurrence occurred in 5.7% (95% CI 2.3%-13.8%, EMR 14.3%, ESD 0.2%, EFTR 12.2–14.3%). Referral to surgery occurred in 9.0% (95% CI 6.7%-12.0%, EMR 8.1%, ESD 9.5%, EFTR 9.8%).

Conclusions

Minimally invasive endoscopic resection techniques including EMR, ESD and EFTR demonstrate high frequencies of technical success with comparable adverse event profiles. They should now be viewed as first-line therapeutic modalities for the management of peri-appendiceal colorectal neoplasia.

Funding Agencies

None

Functional analysis of a putative Bombyx mori cypovirus miRNA BmCPV-miR-10 and its effect on virus replication

Bombyx mori cypovirus (BmCPV) is an important pathogen of silkworm (B. mori), the economically beneficial insect. The mechanism of its interaction with host immune defence system in the process of infection is still not yet completely clear. Researches have demonstrated that virus-encoded microRNAs (miRNA) play a crucial role in regulating host-pathogen interaction, but few reports are available so far on miRNAs encoded by insect viruses, especially the RNA viruses. In this study, a putative miRNA encoded by the 10th segment of BmCPV genomic RNA, BmCPV-miR-10, was identified and functionally analysed. The expression of the putative BmCPV-miR-10 could be detected via stem-loop RT-PCR (reverse transcription-Polymerase Chain Reaction) in the midgut of silkworm larvae infected with BmCPV. BmCSDE1 (B. mori cold shock domain E1 protein) gene was predicted to be a candidate target gene for BmCPV-miR-10 with the miRNA binding site located in 3' untranslated region of its mRNA. The regulation effect of the putative BmCPV-miR-10 on BmCSDE1 was verified in HEK293 cells by lentiviral expression system, in BmN cells by transfecting BmCPV-miR-10 mimics. The qRT-PCR (quantitative real-time PCR) results showed that the putative BmCPV-miR-10 could suppress the expression of BmCSDE1. By injection of BmCPV-miR-10 mimics into the silkworm larvae infected with BmCPV, it was further proved that the putative BmCPV-miR-10 could suppress the expression of BmCSDE1 in vivo, then inhibit the expression of BmApaf-1 (B. mori apoptotic protease activating factor 1), while enhance the replication of BmCPV genomic RNAs to a certain extent. These results implied that the putative BmCPV-miR-10 could down-regulate the expression of BmCSDE1, then suppress the expression of BmApaf-1, thereby created a favourable intracellular environment for virus replication and proliferation.

Yap regulates skeletal muscle fatty acid oxidation and adiposity in metabolic disease

Obesity is a major risk factor underlying the development of metabolic disease and a growing public health concern globally. Strategies to promote skeletal muscle metabolism can be effective to limit the progression of metabolic disease. Here, we demonstrate that the levels of the Hippo pathway transcriptional co-activator YAP are decreased in muscle biopsies from obese, insulin-resistant humans and mice. Targeted disruption of Yap in adult skeletal muscle resulted in incomplete oxidation of fatty acids and lipotoxicity. Integrated 'omics analysis from isolated adult muscle nuclei revealed that Yap regulates a transcriptional profile associated with metabolic substrate utilisation. In line with these findings, increasing Yap abundance in the striated muscle of obese (db/db) mice enhanced energy expenditure and attenuated adiposity. Our results demonstrate a vital role for Yap as a mediator of skeletal muscle metabolism. Strategies to enhance Yap activity in skeletal muscle warrant consideration as part of comprehensive approaches to treat metabolic disease.

Multiyear in-situ L-band microwave radiometry of land surface processes on the Tibetan Plateau

We report a unique multiyear L-band microwave radiometry dataset collected at the Maqu site on the eastern Tibetan Plateau and demonstrate its utilities in advancing our understandings of microwave observations of land surface processes. The presented dataset contains measurements of L-band brightness temperature by an ELBARA-III microwave radiometer in horizontal and vertical polarization, profile soil moisture and soil temperature, turbulent heat fluxes, and meteorological data from the beginning of 2016 till August 2019, while the experiment is still continuing. Auxiliary vegetation and soil texture information collected in dedicated campaigns are also reported. This dataset can be used to validate the Soil Moisture and Ocean Salinity (SMOS) and Soil Moisture Active Passive (SMAP) satellite based observations and retrievals, verify radiative transfer model assumptions and validate land surface model and reanalysis outputs, retrieve soil properties, as well as to quantify land-atmosphere exchanges of energy, water and carbon and help to reduce discrepancies and uncertainties in current Earth System Models (ESM) parameterizations. Measurement cases in winter, pre-monsoon, monsoon and post-monsoon periods are presented.

Circ-CCDC66 accelerates proliferation and invasion of gastric cancer via binding to miRNA-1238-3p

OBJECTIVE

The aim of this study was to examine the expression of circ-CCDC66 in gastric cancer (GC) tissues and cell lines, as well as its correlation with the prognosis of GC. Moreover, the regulatory effects of circ-CCDC66 on biological behaviors of GC cells and its molecular mechanism were explored.

PATIENTS AND METHODS

The relative expression level of circ-CCDC66 in GC tissues and cell lines was determined by quantitative Real Time-Polymerase Chain Reaction (qRT-PCR). The correlation between the circ-CCDC66 level and overall survival of GC patients was analyzed as well. The potential influences of circ-CCDC66 on proliferative and invasive abilities of GC cells were evaluated through 5-Ethynyl-2'-deoxyuridine (EdU), colony formation and transwell assay, respectively. Meanwhile, the cell cycle progression and apoptosis of GC cells affected by circ-CCDC66 were determined. In addition, the direct target miRNA of circ-CCDC66 was predicted and verified by bioinformatics method and Dual-Luciferase reporter gene assay, respectively.

RESULTS

Circ-CCDC66 was significantly up-regulated in GC tissues and cell lines. Up-regulation of circ-CCDC66 indicated markedly worse prognosis of GC patients. Transfection of circ-CCDC66-siRNA remarkably attenuated proliferative and invasive abilities of BGC-823 and MGC-803 cells. Besides, GC cells were arrested in the G0/G1 phase, and the apoptotic rate was remarkably elevated after circ-CCDC66 knockdown. The Dual-Luciferase reporter gene assay verified that circ-CCDC66 bind to miRNA-1238-3p by competing with LHX2 (LIM-homeobox domain 2). MiRNA-1238-3p was significantly down-regulated in GC cells, whereas LHX2 was up-regulated. Furthermore, overexpression of miRNA-1238-3p in GC cells markedly suppressed the LHX2 level.

CONCLUSIONS

Circ-CCDC66 is highly expressed in GC tissues and cell lines. Knockdown of circ-CCDC66 attenuates proliferative and invasive abilities of GC cells. Our results indicate that circ-CCDC66/miRNA-1238-3p/LHX2 axis may be a promising target for GC treatment.

Ultrasound-guided transversus abdominis plane block using ropivacaine and dexmedetomidine in patients undergoing caesarian sections to relieve post-operative analgesia: A randomized controlled clinical trial

Dexmedetomidine, which is a highly selective α2 adrenoreceptor agonist, enhances the analgesic efficacy and prolongs the analgesic duration when administered in combination with local anesthetics. The current study aimed to evaluate the effects of dexmedetomidine combined with ropivacaine in ultrasound-guided transversus abdominis plane (TAP) block on post-operative analgesia following cesarean section (CS). A total of 70 patients scheduled for CS were divided randomly into 2 groups: The ropivacaine (R) group, in which patients were administered bilateral 20 ml 0.3% ropivacaine and 2 ml 0.9% normal saline, and the dexmedetomidine (RD) group, in which patients were administered bilateral 20 ml 0.3% ropivacaine and 2 ml dexmedetomidine (0.5 µg/kg). The primary outcome was pain-free duration, and secondary outcomes included heart rate (HR) and mean blood pressure (MBP) measurements, visual analogue scale (VAS) pain scores, number of patients who required rescue analgesic, time to first request for analgesia and patient satisfaction. There was no significant difference in HR and MBP between the two groups at 1 h post-surgery (P>0.05). However, VAS pain scores decreased at 6 and 8 h post-surgery [2 (1-2) vs. 0 (0-0.25) and 2 (2-3) vs. 0 (0-1), respectively; P<0.05], pain-free duration was prolonged (5.91±1.08 vs. 9.62±1.46 h; P<0.05), the number of patients who required rescue analgesic was reduced (19 vs. 9; P<0.05), the time to first request for analgesia was prolonged (7.10±1.21 vs. 11.60±2.11 h; P<0.05) and patient satisfaction was improved [3.5 (3-4) vs. 4 (4-5); P<0.05] in the RD group compared with the R group. Furthermore, no bradycardia or hypotension was observed. In conclusion, the results of the present study demonstrated that adding 0.5 µg/kg dexmedetomidine to 0.3% ropivacaine used in TAP block in patients undergoing CS prolonged pain-free duration, decreased VAS pain scores, reduced the number of patients who required rescue analgesic, prolonged the time to first request for analgesia and improved the patient satisfaction without serious side effects.

CD200R Is Involved in the Anti-inflammatory Effect of Dexmedetomidine in Lipopolysaccharide-Stimulated Microglia

Dexmedetomidine has been confirmed to have anti-inflammatory effect in numerous diseases. However, the detailed mechanism is still unknown. We explore the hypothesis that CD200R is related to the anti-inflammatory effect of dexmedetomidine. Primary microglia were treated with different concentrations of dexmedetomidine followed with lipopolysaccharide (LPS) for 24 h. Interleukin-6 (IL-6), tumor necrosis factor-α (TNF-α), and interleukin-10 (IL-10) were measured by enzyme-linked immunosorbent assay. Arginase 1 (Arg1), IL-6, and TNF-α were measured by TR-PCR. CD200R was observed by Western blot analysis. We found dexmedetomidine reduced LPS-induced IL-6 and TNF-α production and increase Arg1 in primary microglia. CD200R expression was downregulated by LPS and dexmedetomidine can attenuate the effect of LPS. Our results showed that CD200R may be related to the anti-inflammatory effect of dexmedetomidine.

Three-year longitudinal cognitive functioning in patients recently diagnosed with bipolar disorder

OBJECTIVE

The longitudinal course of neuropsychological functioning after the first manic episode in bipolar disorder is unknown. The present study evaluated cognitive change in bipolar disorder in the first 3 years after the initial manic episode.

METHODS

Ninety-one newly diagnosed patients with bipolar disorder and 61 demographically similar healthy participants received a neuropsychological evaluation assessing multiple cognitive domains at baseline, 1-year, and 3-year time points. Patients also received clinical assessments including mood ratings at all time points.

RESULTS

Patients showed deficits in all domains at baseline, but similar longitudinal trajectories across time relative to healthy participants in most cognitive domains. For processing speed, patients showed more gains than controls from baseline to 1 year, but these gains stabilized thereafter. Patients with alcohol/substance abuse showed an initial delay but subsequent recovery in executive functioning. Patients who discontinued antipsychotic treatment showed better cognitive outcomes in verbal memory.

CONCLUSION

Appropriately treated patients with bipolar disorder showed favorable cognitive outcome in the first 3 years after experiencing an initial manic episode, arguing against cognitive neuroprogression at this stage of the illness. Discontinuation of antipsychotic treatment may be associated with better cognitive outcomes, but clarification of the role of antipsychotics on cognitive functioning requires further investigation.

Research Progress on Postmortem Changes of Computed Tomography Imaging Characteristics on Corpses

Abstract

Postmortem changes on corpses appear immediately after death, and can transform the original structure characteristics of the corpse to different degrees as well as show specific changes on computed tomography （CT） images, sometimes with false positives and false negatives, influencing the identification of injuries or diseases. This paper systematically summarizes the postmortem changes of computed tomography imaging characteristics on corpses, to further expand the application of virtopsy in the practices of forensic pathology identification, and provide reference for the identification of injuries, diseases and changes after normal death.

High-brightness beam tests of the very high frequency gun at the Advanced Photo-injector EXperiment test facility at the Lawrence Berkeley National Laboratory

The very-high-frequency gun (VHF-Gun) is a new concept photo-injector developed and built at the Lawrence Berkeley National Laboratory (LBNL) for generating high-brightness electron beams capable of driving X-ray free electron lasers (FELs) at MHz-class repetition rates. The gun that purposely uses established and mature radiofrequency and mechanical technologies has demonstrated over the last many years the capability of reliably operating in continuous wave mode at the design accelerating fields and required vacuum and mechanical performance. The results of VHF-Gun technology demonstration were reported elsewhere [Sannibale et al., Phys. Rev. Spec. Top.-Accel. Beams 15, 103501 (2012)]; here in this paper, we provide and analyze examples of the experimental results of the first high-brightness beam tests performed at the Advanced Photo-injector EXperiment test facility at LBNL that demonstrated the gun capability of delivering the beam quality required for driving high repetition rate X-ray FELs.

Abstract P6-13-04: Estrogen-alone based hormone replacement therapy (HRT) reduces breast cancer (BrCa) incidence and mortality whereas estrogen plus progestin Provera based HRT increases both BrCa incidence and BrCa mortality: A comparative analysis of Women's Health Initiative trials

OBJECTIVE: To quantitate breast cancer incidence (BrCa-I) and mortality (BrCa-M) outcome differences between the two Women's Health Initiative (WHI) HRT trials,1,2 the ratio of hazards was calculated for estrogen-alone based hormone replacement therapy (E-HRT) vs. placebo (P), and E + progestin Provera (ProgProv) combination HRT vs. P trials.

METHODS: Hazard ratios (HR) of BrCa-I and BrCa-M and 95% confidence intervals (CI) were obtained from both WHI HRT trials. Subsequently, to compare BrCa outcomes between E-HRT vs. E + ProgProv, the ratios of HRs between the trials (HR1/HR2) were estimated separately for i. BrCa-I all women, ii. BrCa-I low Gail score (Gail score &lt;1.75*), and iii. BrCa-M. The 95% CI was derived through logarithmic transformation of the 95% CI originally reported.

RESULTS:

Outcome Comparison, the two WHI HRT randomized trials. Ratio of Hazards, BrCa Incidence and BrCa mortality E-HRT vs. P, HR1 (95% CI)E-HRT + ProgProv vs. P, HR2 (95% CI)HR1/HR2 (95% CI)pBrCa-I All Woman10.77 (0.62-0.95)1.25 (1.07-1.46)0.62 (0.47-0.80)0.0004BrCa-I Low Gail Score* (Gail score &lt;1.75)10.65 (0.50-0.86)1.24 (1.01-1.51)0.53 (0.38-0.74)0.0002BrCa-M20.55 (0.33-0.92)1.44 (0.97-2.15)0.38 (0.20-0.75)0.004*Gail score &lt;1.75; HRs calculated from Reference 1, Figure 3

CONCLUSIONS: Our calculations show that the different outcomes between the two WHI HRT trials, estimated as ratio of hazards, are highly significant on statistical basis, both for BrCa incidence and for BrCa mortality. These findings highlight the potential carcinogenic impact of ProgProv and the major public health benefits of HRT based on E alone.

REFERENCES:

1. Anderson GL, Chlebowski RT, Aragaki AK, et al. Conjugated equine oestrogen and breast cancer incidence and mortality in postmenopausal women with hysterectomy: extended follow-up of the Women's Health Initiative randomised placebo-controlled trial. The Lancet Oncology 2012;13:476-86.

2. Manson JE, Aragaki AK, Rossouw JE, et al. Menopausal Hormone Therapy and Long-term All-Cause and Cause-Specific Mortality: The Women's Health Initiative Randomized Trials. JAMA 2017;318:927-38.

Citation Format: Ragaz J, Qian H, Wong H, Wilson KS, Shakeraneh S, Spinelli JJ. Estrogen-alone based hormone replacement therapy (HRT) reduces breast cancer (BrCa) incidence and mortality whereas estrogen plus progestin Provera based HRT increases both BrCa incidence and BrCa mortality: A comparative analysis of Women's Health Initiative trials [abstract]. In: Proceedings of the 2018 San Antonio Breast Cancer Symposium; 2018 Dec 4-8; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2019;79(4 Suppl):Abstract nr P6-13-04.

Abstract P6-13-06: Estrogen-based hormone replacement [HRT] therapy is substantially more effective than tamoxifen in reducing breast cancer mortality and breast cancer case fatality ratio: Emergence of a new paradigm

OBJECTIVE: To compare, in the setting of breast cancer (BrCa) prevention, the impact of estrogen-based hormone replacement therapy (E-HRT) vs. tamoxifen (TAM) on breast cancer mortality (BrCa-M) and breast cancer case fatality ratio (BrCa-CFR), by analyzing data from the Women's Health Initiative Trial 2 (WHI HRT Trial 2, E-HRT vs. placebo [P])1 and the International Breast Cancer Intervention Study 1 (IBIS-1), TAM vs. P.2

METHODS: Hazard ratios (HR) and confidence intervals (CI) for BrCa incidence and mortality were extracted from the original WHI HRT Trial 2 and IBIS-1 trials.1,2 BrCa-CFRs were estimated by dividing the mortality HR by the incidence HR. Subsequently, to compare E-HRT vs. TAM outcomes, the ratios of HRs (HR1/HR2) between the two trials were estimated separately for BrCa-M and BrCa-CFR. The 95% CI was derived through logarithmic transformation of the 95% CI originally reported.

RESULTS:

Mortality and Case Fatality Outcomes: Impact of E-HRT versus TAM, expressed as ratio of HRs E-HRT vs. Placebo, HR1TAM vs. Placebo, HR2HR1/HR2pMortality0.55 (0.33-0.92)1.19 (0.68-2.10)0.46 (0.22-0.99)0.046Case Fatality0.70 (0.40-1.20)1.68 (0.93-3.01)0.42 (0.18-0.94)0.040

CONCLUSIONS: While acknowledging between-trial comparisons including eligibility differences, E-HRT yields significant reductions in BrCa mortality and case fatality as compared with TAM (54% and 58% respectively). These unexpected breast cancer mortality reductions represent major public health gains, additional to the already known superiority of E-HRT over TAM in terms of skeletal fracture rates and Alzheimer's dementia mortality reduction, and, in women entering menopause, also of cardiac and all-cause mortality reductions.

REFERENCES:

1. Manson JE, Aragaki AK, Rossouw JE, et al. Menopausal Hormone Therapy and Long-term All-Cause and Cause-Specific Mortality: The Women's Health Initiative Randomized Trials. JAMA 2017;318:927-38.

2. Cuzick J, Sestak I, Cawthorn S, et al. Tamoxifen for prevention of breast cancer: extended long-term follow-up of the IBIS-I breast cancer prevention trial. The Lancet Oncology 2015;16:67-75.

Citation Format: Ragaz J, Shakeraneh S, Qian H, Wilson KS, Wong H, Spinelli JJ. Estrogen-based hormone replacement [HRT] therapy is substantially more effective than tamoxifen in reducing breast cancer mortality and breast cancer case fatality ratio: Emergence of a new paradigm [abstract]. In: Proceedings of the 2018 San Antonio Breast Cancer Symposium; 2018 Dec 4-8; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2019;79(4 Suppl):Abstract nr P6-13-06.

Passive Ballistic Microbunching of Nonultrarelativistic Electron Bunches Using Electromagnetic Wakefields in Dielectric-Lined Waveguides

Temporally modulated electron beams have a wide array of applications ranging from the generation of coherently enhanced electromagnetic radiation to the resonant excitation of electromagnetic wakefields in advanced-accelerator concepts. Likewise producing low-energy ultrashort microbunches could be useful for ultrafast electron diffraction and new accelerator-based light-source concepts. In this Letter we propose and experimentally demonstrate a passive microbunching technique capable of forming a picosecond bunch train at ∼6  MeV. The method relies on the excitation of electromagnetic wakefields as the beam propagates through a dielectric-lined waveguide. Owing to the nonultrarelativistic nature of the beam, the induced energy modulation eventually converts into a density modulation as the beam travels in a following free-space drift. The modulated beam is further accelerated to ∼20  MeV while preserving the imparted density modulation.

Surgical management and outcomes of duodenal gastrointestinal stromal tumors

BACKGROUND AND STUDY AIMS

This retrospective study purports to examine these characteristics and compare the surgical procedures available and appropriate for the treatment of patients affected by duodenal GISTs.

PATIENTS AND METHODS

A retrospective examination of reports and studies carried out between May 2012 and March 2017, and covering patients with primary GISTs of the duodenum was performed using modules from the SPSS package. Comparisons of treatment effects resulting from the administration of two differential methods of surgical treatment namely pancreaticoduodenectomy (PD), and limited resection (LR), were effected on the reports of the GIST patients thus selected.

RESULTS

Out of these 62 patients who had undergone resection of duodenal GISTs, 47 (76%) had limited resection (LR) and 15 (24%) underwent pancreaticoduodenectomy (PD). In Multivariate analyses, tumor size was an independent predictive factor for recurrence (p=0.008). ASA, tumor size, and PD were independent and significant prognostic factors on OS (p=0.021, p=0.024, and p=0.030, respectively). In the very low and low risk group, and high-risk group, there were no significant differences in the RFS (recurrence-free survival) and OS (overall survival) between the LR and PD groups.

CONCLUSIONS

When technically feasible, LR should be given due consideration as a reliable and curative option for duodenal GISTs achieving satisfactory RFS and OS.

Constraints on Sub-GeV Dark-Matter-Electron Scattering from the DarkSide-50 Experiment

We present new constraints on sub-GeV dark-matter particles scattering off electrons based on 6780.0 kg d of data collected with the DarkSide-50 dual-phase argon time projection chamber. This analysis uses electroluminescence signals due to ionized electrons extracted from the liquid argon target. The detector has a very high trigger probability for these signals, allowing for an analysis threshold of three extracted electrons, or approximately 0.05 keVee. We calculate the expected recoil spectra for dark matter-electron scattering in argon and, under the assumption of momentum-independent scattering, improve upon existing limits from XENON10 for dark-matter particles with masses between 30 and 100  MeV/c^{2}.

Low-Mass Dark Matter Search with the DarkSide-50 Experiment

We present the results of a search for dark matter weakly interacting massive particles (WIMPs) in the mass range below 20  GeV/c^{2} using a target of low-radioactivity argon with a 6786.0 kg d exposure. The data were obtained using the DarkSide-50 apparatus at Laboratori Nazionali del Gran Sasso. The analysis is based on the ionization signal, for which the DarkSide-50 time projection chamber is fully efficient at 0.1  keVee. The observed rate in the detector at 0.5  keVee is about 1.5  event/keVee/kg/d and is almost entirely accounted for by known background sources. We obtain a 90% C.L. exclusion limit above 1.8  GeV/c^{2} for the spin-independent cross section of dark matter WIMPs on nucleons, extending the exclusion region for dark matter below previous limits in the range 1.8-6  GeV/c^{2}.

Capturing intracellular oncogenic microRNAs with self-assembled DNA nanostructures for microRNA-based cancer therapy

Aberrantly overexpressed oncogenic microRNAs (miRNAs, miRs) are excellent targets for therapeutic interventions.

Aberrantly overexpressed oncogenic microRNAs (miRNAs, miRs) are excellent targets for therapeutic interventions. Nevertheless, thus far, little progress has been made in developing miRNA-based drugs and techniques for clinical applications, especially for overexpressed miRNAs. In this study, we demonstrate that self-assembled DNA nanostructures bearing multiple DNA sequences that are complementary to a target miRNA can effectively capture the overexpressed oncogenic miRNA and subsequently inhibit cancer cell proliferation. Specifically, a DNA nanotube structure that carries functional DNA segments (single-stranded, duplex and hairpin forms) was designed and synthesized to capture two well-known overexpressed miRNAs, miR-21 and miR-155. It was found that all three DNA nanotubes significantly reduced both miRNA levels and inhibited cancer cell growth. Moreover, the capture efficiency was highly concentration dependent and was associated with the structural design of the DNA nanotube. These results demonstrate that through careful design, programmable DNA nanostructures can hijack the natural cellular machinery and can serve as nucleic acid drugs themselves. The concept of using self-assembled DNA nanostructures to disrupt the intracellular machinery for therapeutic purposes opens a new paradigm for exploiting self-assembled DNA nanostructures for miRNA-based anticancer therapy.

Dexmedetomidine inhibits inflammatory reaction in the hippocampus of septic rats by suppressing NF-κB pathway

Dexmedetomidine (DEX) is known to provide neuroprotective effect in the central nervous system. However, the detailed mechanism remains far more elusive. This study was designed to investigate the relevant mechanisms of DEX's neuroprotective effect. Sprague-Dawley (SD) rats were injected with dexmedetomidine and/or Lipopolysaccharide (LPS) intraperitoneally, and inflammatory cytokines in serum and in the hippocampus were measured by enzyme linked immunosorbent assay (ELISA). NF-κB in the brain tissue extracts was analyzed with western-blot. Then, we investigated whether NF-κB inhibitor prevents the elevation of inflammatory cytokines in rats injected with LPS. Our results indicated that compared with the control group, the rats exposed to LPS showed significant cognitive dysfunction. When compared to controls, the levels of TNF-α and IL-6 in the serum and hippocampus homogenate were increased in rats treated with LPS. DEX pretreatment inhibited the rats' TNF-α, IL-6 and NF-κB levels induced by LPS. In response to LPS, PDTC pretreatment restrains the production of proinflammatory cytokines (TNF-α and IL-6). Rats treated with PDTC and DEX alongside LPS exhibited less TNF-α and IL-6 than the LPS treated group. In combination, PDTC and DEX showed addictive effects. Our data suggest that DEX exerts a neuroprotective effect through NF-κB in part after LPS-induced cognitive dysfunction.

[Diagnostic Value of Postmortem CT Angiography in Coronary Atherosclerosis]

OBJECTIVES

To explore the application value of postmortem computed tomography （CT） angiography on diagnosis of coronary atherosclerotic stenosis degree.

METHODS

Based on the previous experimental results, the postmortem CT angiography device of human isolated heart was improved. Different coronary atherosclerotic stenosis degree of sudden death cases was selected. Before the cardiac anatomy, hearts were removed out completely and CT angiography was performed immediately. The CT angiography results were compared with histopathological findings. Meanwhile, the advantages and disadvantages of the angiography device before and after improvement were compared.

RESULTS

The improved angiography device of isolated heart could get better imaging results. The postmortem CT angiography results had high consistency with the histopathological findings on diagnosis of coronary atherosclerotic stenosis degree. And the coronary artery lesions could be revealed more objectively and vividly by 3D reconstruction technology. However, CT angiography could only be used to examine the pathological changes of blood vessels, which might have some limitations on the diagnosis of cause of death.

CONCLUSIONS

Postmortem CT angiography can be used as an additional method for the conventional autopsy in the cases of coronary atherosclerosis.