MetaDrive: Composing Diverse Driving Scenarios for Generalizable Reinforcement Learning.

Driving safely requires multiple capabilities from human and intelligent agents, such as the generalizability to unseen environments, the safety awareness of the surrounding traffic, and the decision-making in complex multi-agent settings. Despite the great success of Reinforcement Learning (RL), most of the RL research works investigate each capability separately due to the lack of integrated environments. In this work, we develop a new driving simulation platform called MetaDrive to support the research of generalizable reinforcement learning algorithms for machine autonomy. MetaDrive is highly compositional, which can generate an infinite number of diverse driving scenarios from both the procedural generation and the real data importing. Based on MetaDrive, we construct a variety of RL tasks and baselines in both single-agent and multi-agent settings, including benchmarking generalizability across unseen scenes, safe exploration, and learning multi-agent traffic. The generalization experiments conducted on both procedurally generated scenarios and real-world scenarios show that increasing the diversity and the size of the training set leads to the improvement of the RL agent's generalizability. We further evaluate various safe reinforcement learning and multi-agent reinforcement learning algorithms in MetaDrive environments and provide the benchmarks. Source code, documentation, and demo video are available at https://metadriverse.github.io/metadrive.

Apela inhibits systemic and renal inflammatory reactions in mice with type I cardiorenal syndrome.

This study investigated the effect of apela on renal function and anti-inflammatory effect on whole body and kidney tissue in mice with type I cardiorenal syndrome (CRS). The murine type I CRS model was established and apela was subcutaneously infused for two weeks. Cardiac and renal functions were evaluated by echocardiography and blood biochemistry, respectively. The systemic and renal inflammatory responses were examined with molecular biological and histological methods. Human renal glomerular endothelial cells (RGECs) were used to evaluate the adhesion effect of monocytes in vitro. Compared to mice from the control group (CRS + vehicle), the plasma levels of N-terminal pro-brain natriuretic peptide, blood urea nitrogen and creatinine were significantly decreased, while the mean left ventricular ejection fraction was increased in apela-treated CRS mice at the 4th week. The expression of monocyte chemoattractant protein-1 (MCP-1) and tumor necrosis factor-α (TNF-α) in the circulation and kidney was decreased in apela-treated mice compared with control mice, and apela improved cardio-renal pathology in mice with type I CRS. Additionally, Apela significantly suppressed the expression of MCP-1, TNF-α, intercellular adhesion molecule-1 and vascular intercellular adhesion molecule-1 in RGECs induced by angiotensin II (Ang II), and inhibited the promoting effect of Ang II on the adhesion of THP-1 cells to RGECs. Western blot results showed that the expression of phosphorylated nuclear factor kappa B (phospho-NFκB) in CRS mice was increased, but the expression of phospho-NFκB was down-regulated after apela treatment. Furthermore, apela significantly inhibited the Ang II-mediated increase in phospho-NFκB expression in RGECs in vitro, but the administration of an apelin peptide jejunum receptor (APJ) inhibitor blocked the inhibitory effect of apela. This study revealed that apela improves cardiorenal function and reduces systemic and renal inflammatory response in type I CRS mice and the apela/APJ system may alleviate renal inflammatory responses by inhibiting the NFκB signalling pathway.

Elabela gene therapy promotes angiogenesis after myocardial infarction.

This study was aimed at investigating whether Elabela (ELA) gene therapy can promote angiogenesis in the treatment of myocardial infarction (MI). The fusion expression plasmid pAAV-3 × Flag/ELA-32 was successfully constructed using molecular cloning technique. The model of acute MI was established by ligating the left anterior descending coronary artery in mice. Adeno-associated virus serotype 9 (AAV9) was injected into the surrounding myocardium and tail vein immediately after the model was established. AAV was injected again from the tail vein one week later. Compared with the MI+PBS (control) group, the serum N-terminal pro-brain natriuretic peptide (NT-proBNP) concentration, and the values of left ventricular end-diastolic diameter (LVDd) and left ventricular end-systolic diameter (LVDs) of the MI+AAV-ELA (gene therapy) group were significantly decreased, while the value of left ventricular ejection fraction was significantly increased at 2 and 4 weeks after operation. Compared with the control group, the expression of CD105 and vWF and the percentage of CD31- and Ki67-co-positive cells were significantly increased in the gene therapy group. Moreover, the expressions of apelin peptide jejunum (APJ) receptor, vascular endothelial growth factor (VEGF), VEGFR2, Jagged1 and Notch3 in the heart tissue around the infarction were up-regulated in mice with gene therapy. The results suggest that ELA activates VEFG/VEGFR2 and Jagged1/Notch3 pathways through APJ to promote angiogenesis after myocardial infarction. ELA gene therapy may be used in the treatment of ischaemic cardiomyopathy in future.

Percutaneous endoscopic transforaminal discectomy for the treatment of L5-S1 lumbar disc herniation and the influence of iliac crest height on its clinical effects.

The present study aimed to explore the clinical effects of percutaneous endoscopic transforaminal discectomy using a transforaminal endoscopic spine system (TESSYS) technique for the treatment of L5-S1 lumbar disc herniation and to analyse the influence of iliac crest height on these clinical effects. The clinical data of 76 patients with L5-S1 single-segment disc herniation treated with TESSYS at The Second Affiliated Hospital and Third Affiliated Hospital of Xi'an Jiaotong University between January and December 2016 were retrospectively analysed. Patients were divided into the following three groups according to the positional relation between the highest point of the iliac crest and the L4 and L5 pedicles in the lateral lumbar, as determined by X-ray: Group I, iliac crest height below the upper edge horizontal line of the L5 pedicle (n=42); group II, iliac crest height between the lower edge horizontal line of the L4 pedicle and the upper edge horizontal line of the L5 pedicle (n=29) and group III, iliac crest height above the lower edge horizontal line of the L4 pedicle (n=5). Changes in the postoperative visual analogue scale (VAS) pain score and Oswestry disability index (ODI) of the lower back and lower limbs were observed, and the effects were compared among the three groups. The mean operating time was 86.5±13.5 min. A single patient experienced cerebrospinal fluid leakage due to a mild tear of the dura mater during the operation, which improved after symptomatic treatment. The same operation was repeated in one patient due to the recurrence of disc herniation. In all patients, the VAS pain score and ODI of the lower back and lower limbs at 1 week and 1, 3 and 12 months following the operation were significantly lower than those before the operation (all P<0.05). Furthermore, the postoperative VAS pain score and ODI of the lower back and lower limbs were poorer in group III (L5-S1 lumbar disc herniation complicated with high iliac crest) than in groups I and II (P<0.05). These results suggested that TESSYS was effective in treating lumbar disc herniation. Whether the iliac crest is higher than the lower edge horizontal line of the L4 pedicle is suggested to be one of the factors influencing the outcome of the operation.

Cryptococcal endocarditis of native valves without immunodeficiency or drug abuse: a case report.

Cryptococcal endocarditis has rarely been reported. Most patients with this condition are associated with risk factors, such as structural heart disease/valve replacement, immunodeficiency/immunosuppression or drug abuse. We report a case of cryptococcal endocarditis of the native valves without any risk factors. A 50-year-old Chinese man was admitted to hospital with fever for 1 month without any underlying heart disease, immunodeficiency, or drug use. He was diagnosed as having Cryptococcus neoformans infective endocarditis and was discharged after valve replacement surgery and long-term antifungal therapy.

Propofol Affects Non-Small-Cell Lung Cancer Cell Biology By Regulating the miR-21/PTEN/AKT Pathway In Vitro and In Vivo.

BACKGROUND: Propofol is a common sedative-hypnotic drug traditionally used for inducing and maintaining general anesthesia. Recent studies have drawn attention to the nonanesthetic effects of propofol, but the potential mechanism by which propofol suppresses non-small-cell lung cancer (NSCLC) progression has not been fully elucidated. METHODS: For the in vitro experiments, we used propofol (0, 2, 5, and 10 µg/mL) to treat A549 cells for 1, 4, and 12 hours and Cell Counting Kit-8 (CCK-8) to detect proliferation. Apoptosis was measured with flow cytometry. We also transfected A549 cells with an microribonucleic acid-21 (miR-21) mimic or negative control ribonucleic acid (RNA) duplex and phosphatase and tensin homolog, deleted on chromosome 10 (PTEN) small interfering ribonucleic acid (siRNA) or negative control. PTEN, phosphorylated protein kinase B (pAKT), and protein kinase B (AKT) expression were detected using Western blotting, whereas miR-21 expression was examined by real-time polymerase chain reaction (RT-PCR). In vivo, nude mice were given injections of A549 cells to grow xenograft tumors; 8 days later, the mice were intraperitoneally injected with propofol (35 mg/kg) or soybean oil. Tumors were then collected from mice and analyzed by immunohistochemistry and Western blotting. RESULTS: Propofol inhibited growth (1 hour, P = .001; 4 hours, P ≤ .0001; 12 hours, P = .0004) and miR-21 expression (P ≤ .0001) and induced apoptosis (1 hour, P = .0022; 4 hours, P = .0005; 12 hours, P ≤ .0001) in A549 cells in a time and concentration-dependent manner. MiR-21 mimic and PTEN siRNA transfection antagonized the suppressive effects of propofol on A549 cells by decreasing PTEN protein expression (mean differences [MD] [95% confidence interval {CI}], -0.51 [-0.86 to 0.16], P = .0058; MD [95% CI], 0.81 [0.07-1.55], P = .0349, respectively), resulting in an increase in pAKT levels (MD [95% CI] = -0.82 [-1.46 to -0.18], P = .0133) following propofol exposure. In vivo, propofol treatment reduced NSCLC tumor growth (MD [95% CI] = -109.47 [-167.03 to -51.91], P ≤ .0001) and promoted apoptosis (MD [95% CI] = 38.53 [11.69-65.36], P = .0093). CONCLUSIONS: Our study indicated that propofol inhibited A549 cell growth, accelerated apoptosis via the miR-21/PTEN/AKT pathway in vitro, suppressed NSCLC tumor cell growth, and promoted apoptosis in vivo. Our findings provide new implications for propofol in cancer therapy and indicate that propofol is extremely advantageous in surgical treatment.

Comparison of conventional fenestration discectomy with Transforaminal endoscopic lumbar discectomy for treating lumbar disc herniation:minimum 2-year long-term follow-up in 1100 patients.

PURPOSE: To compare the efficacy of conventional interlaminar fenestration discectomy (IFD) with transforaminal endoscopic lumbar discectomy (TELD) for treating lumbar disc herniation (LDH). METHODS: The clinical data of 1100 patients who had been diagnosed with LDH between January 2012 and December 2017 were retrospectively analysed. IFD was performed on 605 patients in Group A, whereas TELD was performed on 505 patients in Group B. The Oswestry Disability Index, Visual Analogue Scale for pain and modified MacNab criteria were used to evaluate the outcomes. The surgery duration, intraoperative blood loss, postoperative off-bed activity and postoperative length of hospital stay were recorded. RESULTS: The follow-up period ranged from 24 to 60 months, with an average of 43 months. The excellent and good outcome rates were 93.5% in Group A and 92.6% in Group B. There was no significant difference in efficacy between the groups (P > 0.05). However, Group B had significantly less intraoperative blood loss and shorter bed rest duration and postoperative length of hospital stay than Group A (P < 0.05). There were two cases of postoperative recurrence in Group A and three in Group B. CONCLUSIONS: Although conventional IFD and TELD had similar levels of efficacy in treating LDH, TELD had several advantages. There was less intraoperative bleeding, shorter length of hospital stay and shorter bed rest duration. It can be considered a safe and effective surgical option for treating LDH.

Apela improves cardiac and renal function in mice with acute myocardial infarction.

Apela was recently identified as a new ligand of the apelin peptide jejunum (APJ) receptor. The purpose of this study was to investigate the role of apela in post-myocardial infarction (post-MI) recovery from cardiorenal damage. A murine MI model was established, and apela was then infused subcutaneously for two weeks. Echocardiographs were performed before and after infarction at the indicated times. Renal function was evaluated by serum and urine biochemistry. Immunohistochemistry of heart and kidney tissue was performed by in situ terminal deoxynucleotidyl transferase-mediated dUPT nick end-labelling reaction. Compared to the control group (MI/vehicle), the average value of the left ventricular ejection fraction in apela-treated mice increased by 32% and 39% at 2- and 4-week post-MI, respectively. The mean levels of serum blood urea nitrogen，creatinine, N-terminal pro-brain natriuretic peptide and 24-hour urine protein were significantly decreased at 4-week post-MI in apela-treated mice relative to that of control animals. At the cellular level, we found that apela treatment significantly reduced myocardial fibrosis and cellular apoptosis in heart and kidney tissue. These data suggest that apela improves cardiac and renal function in mice with acute MI. The peptide may be potential therapeutic agent for heart failure.

[Efficacy evaluation of modified lamina osteotomy replantation versus traditional lamina osteotomy replantation in treating lumbar disc herniation with lumbar instability].

OBJECTIVE: To evaluate the clinical effects of modified lamina osteotomy replantation versus traditional lamina osteotomy replantation in the treatment of lumbar disc herniation with lumbar instability. METHODS: The clinical data of 146 patients with unilateral lumbar disc herniation with lumbar instability underwent surgical treatment from March 2008 to March 2013 were retrospectively analyzed. Patients were divided into two groups according to osteotomy replantation pattern. There were 77 patients in the traditional group (underwent traditional lamina osteotomy replantation), including 42 males and 35 females with an average age of (49.4±18.5) years;the lesions occurred on L4,5 in 46 cases, on L55S1 in 31 cases. There were 69 patients in modified group (underwent modified lamina osteotomy replantation), including 37 males and 32 females with an average age of (49.8±17.9) years;the lesions occurred on L4,5 in 40 cases, on L5S1 in 29 cases. The operation time, intraoperative blood loss, complication rate during operation, lamina healing rate, recurrence rate of low back and leg pain were compared between two groups. Visual analogue scales (VAS) and Japanese Orthopadic Association (JOA) scores were used to evaluate the clinical effects. RESULTS: The operation time and intraoperative blood loss were similar between two group (P>0.05). There was significantly different in nerve injury rate(5.80% vs 16.9%) and dural injury rate(1.45% vs 9.09%) between modified group and traditional group(P<0.05). The recurrent rate of low back pain of modified group was higher (91.30%, 63/69) than that of traditional group (76.62%, 59/77), and the intervertebral fusion rate of modified group was lower(8.70%, 6/69) than that of traditional group (29.9%, 23/77) at 3 years after operation. Postoperative VAS scores of all patients were significantly decreased at 6 months, 1, 2, 3 years, and JOA scores were obviously increased (P<0.05). At 1, 2, 3 years after operation, VAS scores of modified group were significantly lower than that of traditional group(P<0.05), and JOA scores of modified group were higher than that of traditional group(P<0.05). CONCLUSIONS: Modified lamina osteotomy replantation has better long-term efficacy(in the aspect of recurrent rate of low back pain, intervertebral fusion rate, VAS and JOA score at three years follow-up) in treating lumbar disc herniation with instability.

Exendin-4 inhibits glioma cell migration, invasion and epithelial-to-mesenchymal transition through GLP-1R/sirt3 pathway.

GLP-1 analogue exendin-4, a glucagon-like peptide 1 receptor (GLP-1R) agonist which shares 53% sequence with GLP-1, plays an essential role in human tumors. However, the function and mechanisms underlying the effects of exendin-4 on glioma cell migration, invasion and epithelial-to-mesenchymal transition are still obscure. Firstly, we demonstrated that GLP-1R was expressed in all glioma cell lines including U87, U251, U373 and A172. Exendin-4 treatment inhibited glioma cell survival, proliferation, migration and invasion. Also, exendin-4 inhibited epithelial-to-mesenchymal transition through positively regulating the expression of E-cadherin (epithelial marker), and negatively regulating the level of Vimentin (mesenchymal marker). Interestingly, we next demonstrated that exendin-4 elevated sirt3 expression dependent on the high level of GLP-1R in U87 and 251 cells. Finally, we confirmed that depletion the level of GLP-1R or sirt3 both reversed the inhibitory action of exendin-4 on glioma cell migration and invasion. These findings demonstrate that exendin-4 treatment suppressed the migration and invasion of glioma cells through GLP-1R/sirt3 pathway and exendin-4 plays an inhibitory effect on glioblastoma cell migration and invasion.

Effects of Cannabinoid Type 2 Receptor Agonist AM1241 on Morphine-Induced Antinociception, Acute and Chronic Tolerance, and Dependence in Mice.

Morphine is a potent opioid analgesic used to alleviate moderate or severe pain, but the development of drug tolerance and dependence limits its use in pain management. Previous studies showed that cannabinoid type 2 (CB2) receptor ligands may modulate opioid effects. However, there is no report of the effect of CB2 receptor agonist on acute morphine tolerance and physical dependence. We therefore investigated the effect of a CB2 receptor agonist (AM1241) on morphine-induced morphine tolerance and physical dependence in mice. Repeated coadministration of AM1241 (1 or 3mg/kg intraperitoneally) and morphine (10mg/kg subcutaneously) for 7days increased the mechanical paw withdrawal threshold in mice as measured by the von Frey filament test, and 3mg/kg AM1241 in combination with morphine increased the thermal paw withdrawal latency as measured by the hot-plate test. Combination with 3mg/kg AM1241 and morphine increased acute morphine antinociception. Coadministration of 1 or 3mg/kg AM1241 and morphine reduced acute morphine tolerance, and 3mg/kg AM1241 reduced chronic morphine tolerance. Coadministration of 1 or 3mg/kg AM1241 and morphine reduced naloxone-precipitated withdrawal jumping, but not diarrhea. Coadministration of AM1241 and morphine did not inhibit spontaneous locomotor activity. Pretreatment with 3mg/kg AM1241 decreased the chronic morphine-induced Iba1 expression in spinal cord. Coadministration of AM1241 (3 mg/kg) reduced the production of interleukin-1ß, tumor necrosis factor-α, and interleukin-6 induced by long-term and acute morphine treatment. Our findings suggest that the coadministration of the CB2 receptor agonist and morphine could increase morphine antinociception and reduce morphine tolerance and physical dependence in mice. PERSPECTIVE: The combination of a CB2 agonist and morphine may provide a new strategy for better treatment of acute and chronic pain and prevention of opioid tolerance and dependence. This finding may also provide a clue for the treatment of opioid tolerance and dependence in clinics.

[ENDOSCOPIC CALCANEOPLASTY FOR Haglund's DEFORMITY WITH HINDFOOT PAIN].

OBJECTIVE: To analyze the effectiveness of endoscopic calcaneoplasty (ECP) for treating hindfoot pain in patients with Haglund's deformity by comparing with conservative treatment. METHODS: According to the included standard, 64 hindfoot pain patients (77 feet) with Haglund's deformity treated between January 2007 and October 2013 were enrolled. Based on the patient's sports habit, 39 patients (49 feet) who had no requirement on sports were given conservative treatment (control group) and 25 patients (28 feet) who had stable sports habit were given ECP (ECP group). There was no significant difference in age, gender, disease duration, disease side, Fowler-Philip angle, and preoperative American Orthopaedic Foot and Ankle Society (AOFAS) ankle-hindfoot score between 2 groups (P > 0.05). RESULTS: The patients were followed up 16-44 months (mean, 33.7 months) in ECP group, and 12-40 months (mean, 37.5 months) in control group. In control group, the syndrome in 34 cases (43 feet) disappeared after 2 weeks; pain was improved in 5?cases (6 feet), and pain disappeared at 3 weeks after orthesis immobilization; hindfoot pain recurred in 24 cases (30 feet) during following-up, 11 cases (13 feet) underwent ECP after 1 year. In ECP group, all incisions healed by first intention without nerve injury; no edema or pain was observed during follow-up. AOFAS ankle-hindfoot score was significantly improved in 2 groups when compared with score at pre-treatment (P < 0.05). With time, AOFAS ankle-hindfoot score gradually decreased in control group, but it gradually increased in ECP group. The AOFAS ankle-hindfoot score of ECP group was significantly higher than that of control group after treatment (P < 0.05). According to Ogilvie-Harris score system at 12 months, the results were excellent in 9 cases, good in 12 cases, and poor in 4 cases, with the excellent and good rate of 84.00% in ECP group; and the results were excellent in 8 cases, good in 14 cases, and poor in 17 cases, with the excellent and good rate of 56.41% in control group. There was significant difference in the excellent and good rate between 2 groups (Z=-2.194, P=0.028). CONCLUSIONS: Under the premise of strict control of surgical indications, the ECP can bring satisfactory effectiveness for treatment of hindfoot pain in patients with Haglund's deformity.

The mitochondrial division inhibitor mdivi-1 attenuates spinal cord ischemia-reperfusion injury both in vitro and in vivo: Involvement of BK channels.

Mitochondrial division inhibitor (mdivi-1), a selective inhibitor of a mitochondrial fission protein dynamin-related protein 1 (Drp1), has been shown to exert protective effects in heart and cerebral ischemia-reperfusion models. The present study was designed to investigate the beneficial effects of mdivi-1 against spinal cord ischemia-reperfusion (SCIR) injury and its associated mechanisms. SCIR injury was induced by glutamate treatment in cultured spinal cord neurons and by descending thoracic aorta occlusion for 20 min in rats. We found that mdivi-1 (10 µM) significantly attenuated glutamate induced neuronal injury and apoptosis in spinal cord neurons. This neuroprotective effect was accompanied by decreased expression of oxidative stress markers, inhibited mitochondrial dysfunction and preserved activities of antioxidant enzymes. In addition, mdivi-1 significantly increased the expression of the large-conductance Ca(2+)- and voltage-activated K(+) (BK) channels, and blocking BK channels by paxilline partly ablated mdivi-1 induced protection. The in vivo experiments showed that mdivi-1 treatment (1 mg/kg) overtly mitigated SCIR injury induced spinal cord edema and neurological dysfunction with no organ-related toxicity in rats. Moreover, mdivi-1 increased the expression of BK channels in spinal cord tissues, and paxilline pretreatment nullified mdivi-1 induced protection after SCIR injury in rats. Thus, mdivi-1 may be an effective therapeutic agent for SCIR injury via activation of BK channels as well as reduction of oxidative stress, mitochondrial dysfunction and neuronal apoptosis. This article is part of a Special Issue entitled SI: Spinal cord injury.

Midazolam inhibits the apoptosis of astrocytes induced by oxygen glucose deprivation via targeting JAK2-STAT3 signaling pathway.

BACKGROUND: There is an increasing interest in the role of astrocytes contributing to the intrinsic bioremediation of ischemic brain injury. The purpose of this study was to disclose the effects and mechanism of midazolam (MDZ) on the proliferation and apoptosis of astrocytes under oxygen glucose deprivation (OGD) condition. METHODS: The astrocytes were assigned randomly into four groups: control group, OGD group, OGD+MDZ group, and OGD+MDZ+IL-6 group. The astrocytes were treated with MDZ at dose of 10 µmol/L in OGD+MDZ group. And in OGD+MDZ+IL-6 group, the astrocytes were treated with MDZ at dose of 10 µmol/L and IL-6 at dose of 50 ng/mL. MTT assay was used to assess cell proliferation, and cell apoptosis was analyzed by TUNEL apoptosis assay kit and flow cytometry. Furthermore, the expression of JAK2, p-JAK2, STAT3, p-STAT3, Bcl-2, Bax and Caspase-3 proteins were determined by western blotting assay. RESULTS: Astrocytes proliferation was decreased obviously in OGD group, while MDZ could increase astrocytes proliferation under OGD condition. Moreover, OGD could induce apoptosis in astrocytes and MDZ could play an anti-apoptotic role. However, IL-6, a JAK2 activator, could attenuate cell proliferation and anti-apoptotic effects of MDZ in astrocytes. In addition, the expression of Bcl-2 protein in MDZ group increased markedly, while the JAK2/STAT3 signal proteins, Bax and Caspase-3 proteins decreased relative to OGD group. But IL-6 could counteract the anti-apoptotic effects of MDZ. CONCLUSION: Midazolam has protective effects on the proliferation and apoptosis of astrocytes via JAK2/STAT3 signal pathway in vitro. We firstly disclose the beneficial roles of midazolam in astrocytes under ischemic condition, which may be a rational treatment selection for ischemic cerebral protection.

Electroacupuncture at ST36 accelerates the recovery of gastrointestinal motility after colorectal surgery: a randomised controlled trial.

OBJECTIVES: To evaluate whether electroacupuncture (EA) at ST36 can accelerate the recovery of gastrointestinal motility after colorectal surgery. METHODS: Forty patients of American Society of Anesthesiologists physical status II and III undergoing elective open resection of malignant colorectal tumours were included in this study. Using a sealed envelope method, the patients were randomly divided into two groups either receiving EA (EA group) or sham EA (SEA group). Data regarding the recovery of bowel function (times to the first bowel sounds, passage of flatus and defaecation) were collected and analysed. RESULTS: In the EA group, the time intervals from surgery to the first bowel movement and passage of flatus were shorter than in the SEA group (13±10 h vs 19±13 h, p<0.05 and 23±14 h vs 32±18 h, p<0.05, respectively). There was no significant difference between the groups regarding the time to first defaecation (68±45 h vs 72±53 h, p>0.05). CONCLUSIONS: EA at ST36 accelerates the recovery of gastrointestinal motility after colorectal surgery. TRIAL REGISTRATION: JJ22011-15.

Nicking endonuclease and target recycles signal amplification assisted quantum dots for fluorescence detection of DNA.

An ultrasensitive fluorescence detection method for DNA based on nicking endonuclease (NEase) and target recycles assisted with CdTe quantum dots (QDs) is reported. In the detection system, when the target DNA is present, it hybridizes with a linker strand to from a duplex, in which the NEase recognizes specific nucleotide sequences and cleaves the linker strand. After nicking, the fragments of the linker strand spontaneously dissociate from the target DNA and another linker strand hybridizes to the target to trigger another strand-scission cycle. On the other hand, when the target was absent, no duplex is formed and no fragment of linker strand is produced. Then CdTe QDs and magnetic beads (MBs), which were all modified with DNA sequences complementary to that of the linker strands are added to the solution to detect the presence of a target DNA. The signal was generated through the difference in Förster resonance energy transfer (FRET) between the MB and CdTe QDs. This method indicates that one target DNA leads to cleavage of hundreds of linker DNA, increasing detection sensitivity by nearly three orders of magnitude. This method should be applicable whenever there is a requirement to detect a specific DNA sequence and can also be used for multicomponent detection.

A role for Gab1/SHP2 in thrombin activation of PAK1: gene transfer of kinase-dead PAK1 inhibits injury-induced restenosis.

To understand the role of epidermal growth factor receptor (EGFR) transactivation in G protein-coupled receptor (GPCR) agonist-induced signaling events, we have studied the capacity of thrombin in the activation of Gab1-SHP2 in vascular smooth muscle cells (VSMCs). Thrombin activated both Gab1 and SHP2 in EGFR-dependent manner. Similarly, thrombin induced Rac1 and Cdc42 activation, and these responses were suppressed when either Gab1 or SHP2 stimulation is blocked. Thrombin also induced PAK1 activation in a time- and EGFR-Gab1-SHP2-Rac1/Cdc42-dependent manner. Inhibition of activation of EGFR, Gab1, SHP2, Rac1, Cdc42, or PAK1 by pharmacological or genetic approaches attenuated thrombin-induced VSMC stress fiber formation and motility. Thrombin activated RhoA in a time-dependent manner in VSMCs. LARG, a RhoA-specific GEF (guanine nucleotide exchange factor), was found to be associated with Gab1 and siRNA-mediated depletion of its levels suppressed RhoA, Rac1 and PAK1 activation. Dominant negative mutant-mediated interference of RhoA activation inhibited thrombin-induced Rac1 and PAK1 stimulation in VSMCs and their stress fiber formation and migration. Balloon injury induced PAK1 activity and interference with its activation led to attenuation of SMC migration from media to intima, resulting in reduced neointima formation and increased lumen size. Inhibition of thrombin signaling by recombinant hirudin also blocked balloon injury-induced EGFR tyrosine phosphorylation and PAK1 activity. These results show that thrombin-mediated PAK1 activation plays a crucial role in vascular wall remodeling and it could be a potential target for drug development against these vascular lesions.

Enzyme-enhanced fluorescence detection of DNA on etched optical fibers.

A novel DNA biosensor based on enzyme-enhanced fluorescence detection on etched optical fibers was developed. The hybridization complex of DNA probe and biotinylated target was formed on the etched optical fiber, and was then bound with streptavidin labeled horseradish peroxidase (streptavidin-HRP). The target DNA was quantified through the fluorescent detection of bi-p,p'-4-hydroxyphenylacetic acid (DBDA) generated from the substrate 4-hydroxyphenylacetic acid (p-HPA) under the catalysis of HRP, with a detection limit of 1 pM and a linear range from 1.69 pM to 169 pM. It is facile to regenerate this sensor through surface treatment with concentrated urea solution. It was discovered that the sensor can retain 70% of its original activity after three detection-regeneration cycles.

NFATc1 targets cyclin A in the regulation of vascular smooth muscle cell multiplication during restenosis.

Platelet-derived growth factor BB (PDGF-BB) induced cyclin A expression and CDK2 activity in vascular smooth muscle cells (VSMC). Inhibition of nuclear factors of activated T cell (NFAT) activation by cyclosporin A (CsA) and VIVIT suppressed PDGF-BB-induced cyclin A expression and CDK2 activity, resulting in blockade of VSMC in the G(1) phase. In addition, CsA- and VIVIT-mediated inhibition of NFATs and small interfering RNA-targeted down-regulation of cyclin A levels suppressed PDGF-BB-induced VSMC DNA synthesis. PDGF-BB also induced cyclin A mRNA levels in VSMC in an NFAT-dependent manner. Cloning and bioinformatic analysis of rat cyclin A promoter revealed the presence of NFAT-binding elements, and PDGF-BB induced the binding of NFATs to these regulatory sequences in a CsA- and VIVIT-sensitive manner. Chromatin immunoprecipitation analysis showed that NFATc1 binds to the cyclin A promoter in response to PDGF-BB in a VIVIT-sensitive manner. Furthermore, PDGF-BB induced cyclin A promoter-luciferase reporter gene activity in VSMC, and it was inhibited by both CsA and VIVIT. Balloon injury induced cyclin A expression and CDK2 activity in rat carotid arteries, and these responses were also blocked by VIVIT. In addition, VIVIT attenuated balloon injury-induced SMC proliferation, resulting in reduced restenosis. Down-regulation of NFATc1 by its small interfering RNA inhibited PDGF-BB-induced cyclin A expression and DNA synthesis both in rat and human VSMC. Together, these findings demonstrate that the cyclin A-CDK2 complex may be a potential effector of NFATs, specifically NFATc1, in mediating SMC multiplication leading to neointima formation. Therefore, NFATs may be used as target molecules for the development of therapeutic agents against vascular diseases such as restenosis.

An essential role for gp130 in neointima formation following arterial injury.

Interleukin (IL)-6 induced vascular smooth muscle cell (VSMC) motility in a dose-dependent manner. In addition, IL-6 stimulated tyrosine phosphorylation of gp130, resulting in the recruitment and activation of STAT-3. IL-6-induced VSMC motility was found to be dependent on activation of gp130/STAT-3 signaling. IL-6 also induced cyclin D1 expression in a time- and gp130/STAT-3-dependent manner in VSMCs. Suppression of cyclin D1 levels via the use of its small interfering RNA molecules inhibited IL-6-induced VSMC motility. Furthermore, balloon injury induced IL-6 expression both at mRNA and protein levels in rat carotid artery. Balloon injury also caused increased STAT-3 phosphorylation and cyclin D1 expression, leading to smooth muscle cell migration from the media to the intimal region. Blockade of gp130/STAT-3 signaling via adenovirus-mediated expression of dngp130 or dnSTAT-3 attenuated balloon injury-induced STAT-3 phosphorylation and cyclin D1 induction, resulting in reduced smooth muscle cell migration from media to intima and decreased neointima formation. Together, these observations for the first time suggest that IL-6/gp130/STAT-3 signaling plays an important role in vascular wall remodeling particularly in the settings of postangioplasty and thereby in neointima formation.