Elevated circulating BMP9 aggravates pulmonary angiogenesis in hepatopulmonary syndrome rats through ALK1-Endoglin-Smad1/5/9 signalling.

BACKGROUND: Bone morphogenetic protein 9 (BMP9) is a hepatokine that plays a pivotal role in the progression of liver diseases. Moreover, an increasing number of studies have shown that BMP9 is associated with hepatopulmonary syndrome (HPS), but its role in HPS is unclear. Here, we evaluated the influence of CBDL on BMP9 expression and investigated potential mechanisms of BMP9 signalling in HPS. METHODS: We profiled the circulating BMP9 levels in common bile duct ligation-induced HPS rat model, and then investigated the effects and mechanisms of HPS rat serum on pulmonary vascular endothelial dysfunction in rat model, as well as in primarily cultured rat pulmonary microvascular endothelial cells. RESULTS: Our data revealed that circulating BMP9 levels were significantly increased in the HPS rats compared to control group. Besides, the elevated BMP9 in HPS rat serum was not only crucial for promoting endothelial cell proliferation and tube formation through the activin receptor-like kinase1 (ALK1)-Endoglin-Smad1/5/9 pathway, but also important for accumulation of monocytes. Treatments with ALK1-Fc or silencing ALK1 expression to inhibit the BMP9 signalling pathway effectively eliminated these effects. In agreement with these observations, increased circulating BMP9 was associated with an increase in lung vessel density and accumulation of pro-angiogenic monocytes in the microvasculature in HPS rats. CONCLUSIONS: This study provided evidence that elevated circulating BMP9, secreted from the liver, promote pulmonary angiogenesis in HPS rats via ALK1-Endoglin-Smad1/5/9 pathway. In addition, BMP9-regulated pathways are also involved in accumulation of pro-angiogenic monocytes in the pulmonary microvasculature in HPS rats.

Dynamic Nomogram for Predicting the Risk of Perioperative Neurocognitive Disorders in Adults.

BACKGROUND: Simple and rapid tools for screening high-risk patients for perioperative neurocognitive disorders (PNDs) are urgently needed to improve patient outcomes. We developed an online tool with machine-learning algorithms using routine variables based on multicenter data. METHODS: The entire dataset was composed of 49,768 surgical patients from 3 representative academic hospitals in China. Surgical patients older than 45 years, those undergoing general anesthesia, and those without a history of PND were enrolled. When the patient's discharge diagnosis was PND, the patient was in the PND group. Patients in the non-PND group were randomly extracted from the big data platform according to the surgical type, age, and source of data in the PND group with a ratio of 3:1. After data preprocessing and feature selection, general linear model (GLM), artificial neural network (ANN), and naive Bayes (NB) were used for model development and evaluation. Model performance was evaluated by the area under the receiver operating characteristic curve (ROCAUC), the area under the precision-recall curve (PRAUC), the Brier score, the index of prediction accuracy (IPA), sensitivity, specificity, etc. The model was also externally validated on the multiparameter intelligent monitoring in intensive care (MIMIC) Ⅳ database. Afterward, we developed an online visualization tool to preoperatively predict patients' risk of developing PND based on the models with the best performance. RESULTS: A total of 1051 patients (242 PND and 809 non-PND) and 2884 patients (6.2% patients with PND) were analyzed on multicenter data (model development, test [internal validation], external validation-1) and MIMIC Ⅳ dataset (external validation-2). The model performance based on GLM was much better than that based on ANN and NB. The best-performing GLM model on validation-1 dataset achieved ROCAUC (0.874; 95% confidence interval [CI], 0.833-0.915), PRAUC (0.685; 95% CI, 0.584-0.786), sensitivity (72.6%; 95% CI, 61.4%-81.5%), specificity (84.4%; 95% CI, 79.3%-88.4%), Brier score (0.131), and IPA (44.7%), and of which the ROCAUC (0.761, 95% CI, 0.712-0.809), the PRAUC (0.475, 95% CI, 0.370-0.581), Brier score (0.053), and IPA (76.8%) on validation-2 dataset. Afterward, we developed an online tool (https://pnd-predictive-model-dynnom.shinyapps.io/ DynNomapp/) with 10 routine variables for preoperatively screening high-risk patients. CONCLUSIONS: We developed a simple and rapid online tool to preoperatively screen patients' risk of PND using GLM based on multicenter data, which may help medical staff's decision-making regarding perioperative management strategies to improve patient outcomes.

Learning to predict in-hospital mortality risk in the intensive care unit with attention-based temporal convolution network.

BACKGROUND: Dynamic prediction of patient mortality risk in the ICU with time series data is limited due to high dimensionality, uncertainty in sampling intervals, and other issues. A new deep learning method, temporal convolution network (TCN), makes it possible to deal with complex clinical time series data in ICU. We aimed to develop and validate it to predict mortality risk using time series data from MIMIC III dataset. METHODS: A total of 21,139 records of ICU stays were analysed and 17 physiological variables from the MIMIC III dataset were used to predict mortality risk. Then we compared the model performance of the attention-based TCN with that of traditional artificial intelligence (AI) methods. RESULTS: The area under receiver operating characteristic (AUCROC) and area under precision-recall curve (AUC-PR) of attention-based TCN for predicting the mortality risk 48 h after ICU admission were 0.837 (0.824 -0.850) and 0.454, respectively. The sensitivity and specificity of attention-based TCN were 67.1% and 82.6%, respectively, compared to the traditional AI method, which had a low sensitivity (< 50%). CONCLUSIONS: The attention-based TCN model achieved better performance in the prediction of mortality risk with time series data than traditional AI methods and conventional score-based models. The attention-based TCN mortality risk model has the potential for helping decision-making for critical patients. TRIAL REGISTRATION: Data used for the prediction of mortality risk were extracted from the freely accessible MIMIC III dataset. The project was approved by the Institutional Review Boards of Beth Israel Deaconess Medical Center (Boston, MA) and the Massachusetts Institute of Technology (Cambridge, MA). Requirement for individual patient consent was waived because the project did not impact clinical care and all protected health information was deidentified. The data were accessed via a data use agreement between PhysioNet, a National Institutes of Health-supported data repository (https://www.physionet.org/), and one of us (Yu-wen Chen, Certification Number: 28341490). All methods were carried out in accordance with the institutional guidelines and regulations.

M2 macrophage accumulation contributes to pulmonary fibrosis, vascular dilatation, and hypoxemia in rat hepatopulmonary syndrome.

Hepatopulmonary syndrome (HPS) markedly increases the mortality of patients. However, its pathogenesis remains incompletely understood. Rat HPS develops in common bile duct ligation (CBDL)-induced, but not thioacetamide (TAA)-induced cirrhosis. We investigated the mechanisms of HPS by comparing these two models. Pulmonary histology, blood gas exchange, and the related signals regulating macrophage accumulation were assessed in CBDL and TAA rats. Anti-polymorphonuclear leukocyte (antiPMN) and anti-granulocyte-macrophage colony stimulating factor (antiGM-CSF) antibodies, clodronate liposomes (CL), and monocyte chemoattractant protein 1 (MCP1) inhibitor (bindarit) were administrated in CBDL rats, GM-CSF, and MCP1 were administrated in bone marrow-derived macrophages (BMDMs). Pulmonary inflammatory cell recruitment, vascular dilatation, and hypoxemia were progressively developed by 1 week after CBDL, but only occurred at 4 week after TAA. Neutrophils were the primary inflammatory cells within 3 weeks after CBDL and at 4 week after TAA. M2 macrophages were the primary inflammatory cells, meantime, pulmonary fibrosis, GM-CSFR, and CCR2 were specifically increased from 4 week after CBDL. AntiPMN antibody treatment decreased neutrophil and macrophage accumulation, CL or the combination of antiGM-CSF antibody and bindarit treatment decreased macrophage recruitment, resulting in pulmonary fibrosis, vascular dilatation, and hypoxemia in CBDL rats alleviated. The combination treatment of GM-CSF and MCP1 promoted cell migration, M2 macrophage differentiation, and transforming growth factor-ß1 (TGF-ß1) production in BMDMs. Conclusively, our results highlight neutrophil recruitment mediates pulmonary vascular dilatation and hypoxemia in the early stage of rat HPS. Further, M2 macrophage accumulation induced by GM-CSF/GM-CSFR and MCP1/CCR2 leads to pulmonary fibrosis and promotes vascular dilatation and hypoxemia, as a result, HPS develops.

Effects of dexmedetomidine on the function of distal organs and oxidative stress after lower limb ischaemia-reperfusion in elderly patients undergoing unilateral knee arthroplasty.

AIMS: This study aims to evaluate the effects of dexmedetomidine on organ function, inflammation response, and oxidative stress in elderly patients following iatrogenic lower limb ischaemia-reperfusion (IR) during unilateral total knee arthroplasty. METHODS: Following unilateral total knee arthroplasty, 54 elderly patients were randomized to receive either intraoperative intravenous injection of dexmedetomidine (n = 27) or equivalent volume of 0.9% saline (n = 27). Blood samples were harvested at 5 minutes before lower limb tourniquet release (baseline); and 1, 6 and 24 hours after tourniquet release. Surrogate markers of cardiac, pulmonary, hepatic and renal function, oxidative stress, inflammatory response, along with parasympathetic and sympathetic activity were recorded and analysed. RESULTS: The levels of blood xanthine oxidase, creatine kinase, lactic acid and respiratory index increased in patients following tourniquet-induced lower limb IR injury. Dexmedetomidine administration decreased the respiratory index (P = .014, P = .01, and P = .043) and the norepinephrine level (P < .001) at 1, 6 and 24 hours; and decreased the xanthine oxidase level (P = .049, P < .001) at 6 and 24 hours after tourniquet release compared with the Control group. Other measurements, including creatine kinase isoenzyme, lactate dehydrogenase, creatinine, urea nitrogen, glutamic-oxalacetic transaminase, glutamic-pyruvic transaminase, malondialdehyde, interleukin-1, interleukin-6 and tumour necrosis factor-α, were not statistically significantly different between the 2 groups. CONCLUSIONS: Intraoperative dexmedetomidine administration in elderly patients dampens the deterioration in respiratory function and suppresses the oxidative stress response in elderly patients following iatrogenic lower limb IR injury.

The Effect of Mechanical Ventilation With Low Tidal Volume on Blood Loss During Laparoscopic Liver Resection: A Randomized Controlled Trial.

BACKGROUND: Control of bleeding during laparoscopic liver resection (LLR) is important for patient safety. It remains unknown what the effects of mechanical ventilation with varying tidal volumes on bleeding during LLR. Thus, this study aims to investigate whether mechanical ventilation with low tidal volume (LTV) reduces surgical bleeding during LLR. METHODS: In this prospective, randomized, and controlled clinical study, 82 patients who underwent scheduled LLR were enrolled and randomly received either mechanical ventilation with LTV group (6-8 mL/kg) along with recruitment maneuver (once/30 min) without positive end-expiratory pressure (PEEP) or conventional tidal volume (CTV; 10-12 mL/kg) during parenchymal resection. The estimated volume of blood loss during parenchymal resection and the incidence of postoperative respiratory complications were compared between 2 groups. RESULT: The estimated volume of blood loss (median [interquartile range {IQR}]) was decreased in the LTV group compared to the CTV group (301 [148, 402] vs 394 [244, 672] mL, P = .009); blood loss per cm2 of transected surface of liver (5.5 [4.1, 7.7] vs 12.2 [9.8, 14.4] mL/cm2, P < .001) and the risk of clinically significant estimated blood loss (>800 mL) were reduced in the LTV group compared to the CTV group (0/40 vs 8/40, P = .003). Blood transfusion was decreased in the LTV group compared to the CTV group (5% vs 20% of patients, P = .043). No patient in the LTV group but 2 patients in the CTV group were switched from LLR to open hepatectomy. Airway plateau pressure was lower in the LTV group compared to the CTV group (mean ± standard deviation [SD]) (12.7 ± 2.4 vs 17.5 ± 3.5 cm H2O, P = .002). CONCLUSIONS: Mechanical ventilation with LTV may reduce bleeding during laparoscopic liver surgery.

Effects of circadian rhythm on Narcotrend index and target-controlled infusion concentration of propofol anesthesia.

BACKGROUND: The effects of circadian rhythms on drug metabolism and efficacy are being increasingly recognized. However, the extent to which they affect general anesthesia remains unclear. This study aims to investigate the effects of circadian rhythms on anesthetic depth and the concentrations of propofol target-controlled infusion (TCI). METHODS: Sixty patients undergoing laparoscopic surgeries were sequentially assigned to four groups. Group ND (n = 15): Propofol TCI with Narcotrend monitor during the day (8:00-18:00), Group NN (n = 15): Propofol TCI with Narcotrend monitor during the night (22:00-5:00), Group CLTD (n = 15): Propofol closed-loop TCI guided by bispectral index (BIS) during the day (8:00-18:00), Group CLTN (n = 15): Propofol closed-loop TCI guided by BIS during the night (22:00-5:00). The Narcotrend index, mean arterial pressure (MAP) and heart rate (HR) were compared between group ND and NN at 7 time points, from 5 min before induction to the end of operation. The propofol TCI concentrations, MAP and HR were compared between group CLTD and CLTN at 7 time points, from 5 min after induction to the end of operation. RESULTS: The Narcotrend index, MAP, and HR in group NN were lower than those in group ND from the beginning of mechanical ventilation to the end of operation (p < 0.05). The propofol TCI concentrations in group CLTN were lower than those in group CLTD from the beginning of operation to the end of operation (p < 0.05). CONCLUSION: Circadian rhythms have a significant effect on the depth of anesthesia and drug infusion concentrations during propofol TCI. When using general anesthesia during night surgery, the propofol infusion concentration should be appropriately reduced compared to surgery during the day. TRIAL REGISTRATION: The present study was registered on the ClinicalTrials.gov website ( NCT02440269 ) and approved by the Medical Ethics Committee of Southwest Hospital of Third Military Medical University (ethics lot number: 2016 Research No. 93). All patients provided informed written consent to participate in the study.

Liposomal Bupivacaine Single-Injection Compared With Continuous Local Anesthetic Nerve Blocks for Painful Surgeries: A Meta-Analysis of Randomized Controlled Trials and Trial Sequential Analysis.

OBJECTIVE: This meta-analysis aimed to determine whether liposomal bupivacaine (LB) single-injection could achieve an analgesic effect similar to that of continuous local anesthetic nerve blocks (CNBs) after painful surgeries. METHODS: Embase, PubMed, and the Cochrane Library databases were comprehensively searched. Randomized controlled trials (RCTs) with a modified Jadad score ≥ 4 compared LB single-injection with CNBs in patients after painful surgeries were included. The primary outcomes were VAS pain score and opioid consumption. The secondary outcomes were complications and length of hospital stay. Review Manager 5.3 and trial sequential analysis (TSA) 0.9.5.10 were used to analyze the extracted data. RESULTS: Six RCTs of 625 patients were included for meta-analysis. Both groups in 5 RCTs described standard concomitant treatment with multimodal analgesia. There were no significant differences in mean VAS scores for postoperative day 0 (P = 0.12), day 1 (P = 0.18), and day 2 (P = 0.41); highest VAS scores for day 0 (P = 0.18), day 1 (P = 0.46), and day 2 (P = 0.18); total opioid consumption for day 0 (P = 0.05), day 1 (P = 0.28), and day 2 (P = 0.57); complications (P = 0.30); and length of hospital stay (P = 0.64) between the 2 groups. TSA of primary outcomes showed that all cumulative Z curves failed to cross the TSA boundary and did not reach the required information size. CONCLUSIONS: This meta-analysis showed that LB single-injection and CNBs have similar efficacy of pain relief and safety in patients after painful surgeries when concomitant with multimodal analgesia. However, the results of TSA indicate that further trials are still needed to confirm these findings.

Dexmedetomidine-Mediated Prevention of Renal Ischemia-Reperfusion Injury Depends in Part on Cholinergic Anti-Inflammatory Mechanisms.

BACKGROUND: Organ ischemia-reperfusion injury often induces local and systemic inflammatory responses, which in turn worsen organ injury. These inflammatory responses can be regulated by the central nervous system, particularly by the vagal nerve and nicotinic acetylcholine receptors, which are the key components of cholinergic anti-inflammatory pathway. Activation of the cholinergic anti-inflammatory pathway can suppress excessive inflammatory responses and be a potential strategy for prevention of ischemia-reperfusion injury of organs including the kidney. METHODS: Vagal nerve activity, plasma acetylcholine, catecholamine and inflammatory mediators, renal tissue injury, and cell death were measured in mice with bilateral renal ischemia/reperfusion with or without treatment with dexmedetomidine (Dex), an α2-adrenergic receptor agonist. RESULTS: Dex significantly increased the discharge frequency of the cervical vagal nerve by up to 142 Hz (mean) (P < .001), and preserved kidney gross morphology and structure and attenuated cell apoptosis after ischemia-reperfusion. Furthermore, Dex also significantly increased acetylcholine release to 135.8 pmol/L (median) when compared to that (84.7 pmol/L) in the sham group (P < .001) and reduced the levels of several inflammatory mediators induced by renal ischemia/reperfusion. All the effects were abolished by vagotomy, splenectomy, or combinative administration of atipamezole, an α2-adrenergic receptor antagonist. CONCLUSIONS: Our findings suggest that Dex provides renoprotection, at least in part, through anti-inflammatory effects of the parasympathetic nervous system activation in addition to its direct actions on α2-adrenergic receptors.

Loss of cell polarity regulated by PTEN/Cdc42 enrolled in the process of Hepatopulmonary Syndrome.

One central factor in hepatopulmonary syndrome (HPS) pathogenesis is pulmonary vascular remodelling (PVR) which involves dysregulation of proliferation and migration in pulmonary microvascular endothelial cells (PMVECs). Growing evidence suggests that Apical/basolateral polarity plays an important role in cell proliferation, migration, adhesion and differentiation. In this study, we explored whether cell polarity is involved and critical in experimental HPS rats that are induced by common bile duct ligation (CBDL). Cell polarity related proteins were analysed in CBDL rats lung and PMVECs under the HPS serum stimulation by immunofluorescence assay. Cdc42/PTEN activity, cell proliferation and migration and Annexin A2 (AX2) in PMVECs were determined, respectively. Cell polarity related proteins, lost their specialized luminal localization in PMVECs of the CBDL rat. The loss of cell polarity was induced by abnormal activity of Cdc42, which was strongly enhanced by the interaction between p-PTEN and Annexin A2 in PMVECs, after treatment with serum from CBDL rats. It led to over-proliferation and high migration ability of PMVECs. Down-regulation of PTEN-Cdc42 activity in PMVECs restored cell polarity and thus reduced their ability of migration and proliferation. Our study suggested that the loss of cell polarity plays a critical role in the pathogenesis of HPS-associated PVR and may become a potentially effective therapeutic target.

Inhibition of tyrosine kinases protects against lipopolysaccharide-induced acute lung injury by preventing nuclear export of Nrf2.

Acute Lung Injury is a common severe pathological condition that is usually caused by lipopolysaccharide (LPS) infection from bacteria. Enhanced activity of nuclear factor erythroid 2-related factor 2 (Nrf2) could attenuate LPS induced lung injury, However, it still remains unknown whether the enhanced activity of Nrf2 via suppression of Nrf2 nucleus export attenuates the LPS induced lung injury. The aim of this study is to investigate the effects of inhibitors of Fyn on the LPS-induced acute lung injury and to explore its underlying molecular mechanisms. Nrf2 localization in the cells was observed by using confocal microscopy and its transcriptional activation was measured by Electrophoretic Mobility Shift Assay and controlled genes expression levels. The lung injury severity was examined by histopathological scoring and oxidative stress level. In this study, we showed that PP2, LMB, and Nrf2 Y568A abrogated Nrf2 nuclear export and thus enhance the Nrf2 transcriptional activity. PP2 attenuated lung injury and the reduction of cells viability induced by LPS. The current study demonstrated, for the first time, that increase of expression of Nrf2 controlled protective genes via suppression of Nrf2 nucleus export could attenuate lung injury.

A self-organized actomyosin drives multiple intercellular junction disruption and directly promotes neutrophil recruitment in lipopolysaccharide-induced acute lung injury.

Acute lung injury (ALI), with the hallmarks of vascular integrity disruption and neutrophil recruitment, is associated with high morbidity and mortality. Enhanced actomyosin assembly contributes to endothelial cell contact dysfunction. However, the roles and mechanisms of actomyosin assembly in ALI are not totally clear. We investigated the dynamic alterations and roles of actomyosin in ALI in vivo and in vitro models induced by LPS. Pulmonary levels of E-cadherin, vascular endothelial-cadherin, occludin, myosin phosphatase target subunit 1, and thymosin ß4 were decreased, and the number and activity of neutrophils and the levels of actomyosin, p-ρ-associated protein kinase, p-myosin light-chain kinase, and profilin1 were increased within 3 d after LPS administration, and then, those alterations were recovered within the next 4 d, which was consistent with the alterations of lung histology, vascular permeability, edema, and serum levels of IL-6 and TNF-α. Direct or indirect inhibition of increased F-actin or myosin assembly ameliorated the reduction of intercellular junction molecules, the activation and migration of neutrophils, and the degree of lung injury. Moreover, neutrophil activation further promoted actomyosin assembly and aggravated lung injury. Conclusively, the enhancement of self-organized actomyosin contributes to alveolar-capillary barrier disruption and neutrophil recruitment in inflammatory response, which is a potential therapeutic target for ALI.-Chen, B., Yang, Z., Yang, C., Qin, W., Gu, J., Hu, C., Chen, A., Ning, J., Yi, B., Lu, K. A self-organized actomyosin drives multiple intercellular junction disruption and directly promotes neutrophil recruitment in lipopolysaccharide-induced acute lung injury.

Osteopontin mediates necroptosis in lung injury after transplantation of ischaemic renal allografts in rats.

BACKGROUND: Respiratory complications after surgery are associated with morbidity and mortality. Acute lung injury can result from the systemic inflammatory response after acute kidney injury. The mechanisms behind this remote injury are not fully understood. In this study, a renal transplantation model was used to investigate remote lung injury and the underlying molecular mechanisms, especially the role of osteopontin (OPN). METHODS: In vitro, human lung epithelial cell line (A549) and monocyte/macrophage cell line (U937) were challenged with tumour necrosis factor-alpha (TNF-α) in combination with OPN. In vivo, the Fischer rat renal grafts were extracted and stored in 4°C University of Wisconsin preserving solution for up to 16 h, and transplanted into Lewis rat recipients. Lungs were harvested on Day 1 after grafting for further analysis. RESULTS: Renal engraftment was associated with pathological changes and an increase in TNF-α and interleukin-1 beta in the lung of the recipient. OPN, endoplasmic reticulum (ER) stress, and necroptosis were increased in both the recipient lung and A549 cells challenged with TNF-α. Exogenous OPN exacerbated lung injury and necroptosis. Suppression of OPN through siRNA reduced remote lung injury by mitigation of ER stress, necroptosis, and the inflammatory response. CONCLUSIONS: Renal allograft transplant triggers recipient remote lung injury, which is, in part, mediated by OPN signalling. This study may provide a molecular basis for strategies to be developed to treat such perioperative complications.

miR144-3p inhibits PMVECs excessive proliferation in angiogenesis of hepatopulmonary syndrome via Tie2.

BACKGROUND/AIM: Increasing evidence show microRNAs (miRNAs) are associated with hepatopulmonary syndrome (HPS). The aim of this study was to investigate the role of miR-144 in the angiogenesis of HPS, as well as to identify its underlying mechanism. METHODS: The expression levels of miR-144-3p were assessed in pulmonary micro-vascular endothelial cells (PMVECs), as well as in lung tissues from rats with HPS. We predicted the potential target of miR-144-3p. Tyrosine kinase 2(Tie2) was identified as a target gene of miR144-3p, which has an essential role in the angiogenesis of lung vessel. In addition, the effects of miR-144-3p regulated on Tie2 was examined. The upregulation and down-regulation of miR-144-3p can affect the proliferation of PMVECs. RESULTS: We found that the levels of miR-144-3p were frequently downregulated in HPS tissues and cell lines, and overexpression of miR-144-3p dramatically inhibited PMVECs proliferation and cell cycle. We further verified the Tie2 as a novel and direct target of miR-144-3p in HPS. CONCLUSION: miR-144-3p can negatively regulate PMVECs proliferation by Tie2 expression. In addition, overexpression of miR-144-3p may prove beneficial as a therapeutic strategy for HPS treatment.

Investigation of the accuracy of a noninvasive continuous blood pressure device in different age groups and its ability in detecting hypertension and hypotension: an observational study.

BACKGROUND: CNAP monitor is a continuous and noninvasive blood pressure (BP) measurement device that can be used in intraoperative monitoring. But whether its accuracy changes with age and its detectability of hypertension and hypotension are still unclear. This study was to investigate the agreement of CNAP and invasive arterial pressure (IAP) in different age groups, and the ability of CNAP to detect hypertension and hypotension. METHODS: This observational study enrolled 48 Chinese patients undergoing surgery under general anaesthesia, including 25 relatively old patients (age between 50 and 70) and 23 relatively young patients (age between 18 and 49). IAP was monitored at the radial artery and CNAP was applied on the opposite arm simultaneously. Paired BP data in the entire surgery were recorded, and analyzed with Bland Altman plot and Spearman correlation. The ratio of the hypertension and hypotension episodes detected by IAP and CNAP was analyzed using chi-square test. RESULTS: 7990 valid paired BP data were analyzed, wherein 4186 data were from 25 relatively old patients, and the other data were from 23 relatively young patients. Bias (SD) for relatively old patients was: systolic BP (SBP): - 6.5 (18.6) mm Hg; diastolic BP (DBP): 9.3 (7.8) mmHg; and mean BP (MBP): 4.2 (9.5) mm Hg. Bias (SD) for relatively young patients was: SBP: - 6.2 (12.1) mm Hg; DBP: 10.6 (6.9) mmHg; and MBP: 4.8 (7.3) mm Hg. The correlation between CNAP and IAP was higher in MBP than those in SBP and DBP, and it decreased with the increase of age. Comparing to IAP, CNAP tended to miss reporting a high SBP, low DBP and low MBP, and misinform a low SBP, high DBP and high MBP. CONCLUSION: CNAP showed acceptable agreement with IAP in MBP for all age groups, but reduced agreement with IAP in SBP and DBP, especially for relatively old patients. Ability of CNAP to detect hypertension and hypotension episodes was weaker than IAP. Therefore, CNAP monitor is suitable for young patients and hemodynamically stable surgery, but may not be recommended for old patients with arteriosclerosis and diabetes or surgeries expecting to have fluctuating blood pressure.

Combined ultrasound and nerve stimulator-guided deep nerve block may decrease the rate of local anesthetics systemic toxicity: a randomized clinical trial.

BACKGROUND: Ultrasound guidance might decrease the incidence of local anesthetics systemic toxicity (LAST) for many peripheral nerve blocks compared with nerve stimulator guidance. However, it remains uncertain whether ultrasound guidance is superior to nerve stimulator guidance for deep nerve block of the lower extremity. This study was designed to investigate whether deep nerve block with ultrasound guidance would decrease the incidence of LAST compared with that with nerve stimulator guidance, and to identify associated risk factors of LAST. METHODS: Three hundred patients undergoing elective lower limb surgery and desiring lumbar plexus blocks (LPBs) and sciatic nerve blocks (SNBs) were enrolled in this study. The patients were randomly assigned to receive LPBs and SNBs with ultrasound guidance (group U), nerve stimulator guidance (group N) or dual guidance (group M). The primary outcome was the incidence of LAST. The secondary outcomes were the number of needle redirection, motor and sensory block onset and nerve distribution restoration time, as well as associated risk factors. RESULTS: There were 18 patients with LAST, including 12 in group U, 4 in group N and 2 in group M. By multiple comparisons among the three groups, we found that the incidence of LAST in group U (12%) was significantly higher than that in group N (4%)(P = 0.037) and group M(2%)(P = 0.006). The OR of LAST with hepatitis B (HBV) infection and the female sex was 3.352 (95% CI,1.233-9.108, P = 0.013) and 9.488 (95% CI,2.142-42.093, P = 0.0004), respectively. CONCLUSIONS: Ultrasound guidance, HBV infection and the female sex were risk factors of LAST with LPBs and SNBs. For patients infected with HBV or female patients receiving LPBs and SNBs, we recommended that combined ultrasound and nerve stimulator guidance should be used to improve the safety. TRIAL REGISTRATION: This study was approved by the Ethical Committee of the First Affiliated Hospital of Army Medical University. The protocol was registered prospectively with the Chinese Clinical Trial Registry ( ChiCTR-IOR-16008099 ) on March 15, 2016.

AMD3100 treatment attenuates pulmonary angiogenesis by reducing the c-kit (+) cells and its pro-angiogenic activity in CBDL rat lungs.

Recent studies have shown that pulmonary angiogenesis is an important pathological process in the development of hepatopulmonary syndrome (HPS), and growing evidence has indicated that Stromal cell-derived factor 1/C-X-C chemokine receptor type 4 (SDF-1/CXCR4) axis is involved in pulmonary vascular disease by mediating the accumulation of c-kit+ cells. This study aimed to test the effect of AMD3100, an antagonist of CXCR4, in HPS pulmonary angiogenesis. Common bile duct ligation (CBDL) rats were used as experimental HPS model and were treated with AMD3100 (1.25mg/kg/day, i.p.) or 0.9% saline for 3weeks. The sham rats underwent common bile duct exposure without ligation. The c-kit+ cells accounts and its angiogenic-related functions, prosurvival signals, pulmonary angiogenesis and arterial oxygenation were analysed in these groups. Our results showed that pulmonary SDF-1/CXCR4, Akt, Erk and VEGF/VEGFR2 were significantly activated in CBDL rats, and the numbers of circulating and pulmonary c-kit+ cells were increased in CBDL rats compared with control rats. Additionally, the angiogenic-related functions of c-kit+ cells and pulmonary microvessel counts were also elevated in CBDL rats. CXCR4 inhibition reduced pulmonary c-kit+ cells and microvessel counts and improved arterial oxygenation within 3weeks in CBDL rats. The pulmonary prosurvival signals and pro-angiogenic activity of c-kit+ cells were also down-regulated in AMD3100-treated rats. In conclusion, AMD3100 treatment attenuated pulmonary angiogenesis in CBDL rats and prevented the development of HPS via reductions in pulmonary c-kit+ cells and inhibition of the prosurvival signals. Our study provides new insights in HPS treatment.

Dexmedetomidine attenuates lung apoptosis induced by renal ischemia-reperfusion injury through α2AR/PI3K/Akt pathway.

BACKGROUND: Acute lung injury caused by renal ischemia-reperfusion is one of the leading causes of acute kidney injury-related death. Dexmedetomidine, an α2-adrenergic agonist sedative, has been found to have protective effects against acute kidney injury and remote lung injury. We sought to determine whether dexmedetomidine can exert its anti-apoptotic effects in acute lung injury after acute kidney injury, in addition to its common anti-inflammatory effects, and to determine the underlying mechanisms. METHODS: In vivo, acute kidney injury was induced by 60 min of kidney ischemia (bilateral occlusion of renal pedicles) followed by 24 h of reperfusion. Mice received dexmedetomidine (25 µg/kg, i.p.) in the absence or presence of α2-adrenergic antagonist atipamezole (250 µg/kg, i.p.) before IR. Histological assessment of the lung was conducted by HE staining and arterial blood gases were measured. Lung apoptosis was assessed by terminal deoxynucleotidyl transferase-mediated dUTP nick end-labeling assay. The expression of caspase 3 and p-Akt in lung tissue was detected by western blot. In vitro, C57BL/6J mice pulmonary microvascular endothelial cells were treated with serum from mice obtained following sham or IR. Dexmedetomidine was given before serum stimulation in cells, alone or with atipamezole or LY294002. Cell viability was assessed by CCK 8 assay. Cell apoptosis was examined by Hoechst staining and Annexin V-FITC/PI staining flow cytometry analysis. Mitochondrial membrane potential was measured by flow cytometry. The expression of p-Akt, caspase 3, Bcl-2 and Bax was measured by western blot. RESULTS: In vivo, dexmedetomidine remarkably mitigated pathohistological changes and apoptosis and significantly increased p-Akt expression in the lung. In addition, dexmedetomidine also slightly improved oxygenation in mice after IR, which can be abolished by atipamezole. In vitro, dexmedetomidine significantly inhibited IR serum-induced loss of viability and apoptosis in PMVECs. Dexmedetomidine increased p-Akt in a time- and dose-dependent manner, and down-regulated the expression of caspase 3 and Bax and up-regulated the Bcl-2 expression in PMVECs. The changes of MMP were also improved by dexmedetomidine. Whilst these effects were abolished by Atipamezole or LY294002. CONCLUSION: Our results demonstrated that dexmedetomidine attenuates lung apoptosis induced by IR, at least in part, via α2AR/PI3K/Akt pathway.

Comparison of lumbar plexus block using the short axis in-plane method at the plane of the transverse process and at the articular process: a randomized controlled trial.

BACKGROUND: Although the safety and effectiveness of the short-axis in-plane method has been confirmed for lumbar plexus block, the operation is difficult and has a high rate of epidural spread at the plane of the articular process. Therefore, we developed a new in-plane technique, called the beach chair method, which displays images from the transverse process. We compared the operative difficulty and incidence of epidural spread of the beach chair method with those of the control method (at the plane of the articular process) in this randomized controlled clinical trial. METHODS: Sixty patients, aged 18 to 75 years, scheduled for unilateral arthroscopic knee surgery were randomized to receive double-guided lumbar plexus block by the beach chair method (n = 30) or the control method (n = 30) with 30 ml 0.5% ropivacaine hydrochloride; all patients received a sciatic nerve block with 10 ml 1% lidocaine hydrochloride and 10 ml 0.5% ropivacaine hydrochloride. RESULTS: The incidence of epidural spread after lumbar plexus block was significantly lower in the beach chair group than that in the control group [1 case (3.3%) vs. 9 (30.0%), P = 0.006]. Moreover, the imaging time (34.2 ± 16.7 s vs. 48.9 ± 16.8 s, P = 0.001), needling time (85.0 ± 45.3 s vs. 131.4 ± 88.2 s, P = 0.013) and number of needle punctures (2.7 ± 1.3 vs. 4.5 ± 2.1, P = 0.000) were significantly lower in the beach chair group than those in the control group; the ultrasound visibility score of the beach chair group was better than that of the control group. There were no significant differences in the remaining indicators. CONCLUSIONS: The beach chair method was easier and was associated with a lower incidence of epidural spread than the control method. Therefore, the beach chair method (at the plane of the transverse process) provides another promising option for lumbar plexus block for the non-obese population. TRIAL REGISTRATION: Chinese Clinical Trial Registry (ChiCTR), Registration number:ChiCTR-INR-15007505, registered on November 06, 2015.

The angiogenic related functions of bone marrow mesenchymal stem cells are promoted by CBDL rat serum via the Akt/Nrf2 pathway.

Hepatopulmonary syndrome (HPS) is a complication of severe liver disease. It is characterized by an arterial oxygenation defect. Recent studies have demonstrated that pulmonary angiogenesis contributes to the abnormal gas exchange found in HPS. Additionally, mesenchymal stem cells (MSCs) are considered the stable source of VEGF-producing cells and have the potential to differentiate into multiple cell types. However, it has not been determined whether bone marrow mesenchymal stem cells (BM-MSCs) are mobilized and involved in the pulmonary angiogenesis in HPS. In this study, a CFU-F assay showed that the number of peripheral blood MSCs was increased in common bile duct ligation (CBDL) rats; however, there was no significant difference found in the number of BM-MSCs. In vitro, CBDL rat serum induced the overexpression of CXCR4 and PCNA in BM-MSCs. Consistently, the directional migration as well as the proliferation ability of BM-MSCs were enhanced by CBDL rat serum, as determined by a transwell migration and MTT assays. Moreover, the secretion of VEGF by BM-MSCs increased after treatment with CBDL rat serum. We also found that the expression of phospho-Akt, phospho-ERK, and Nrf2 in BM-MSCs was significantly up-regulated by CBDL rat serum in a time dependent manner, and the blockage of the Akt/Nrf2 signalling pathway with an Akt Inhibitor or Nrf2 siRNA, instead of an ERK inhibitor, attenuated the migration, proliferation and paracrine capacity of BM-MSCs. In conclusion, these findings indicated that the number of MSCs increased in the peripheral blood of CBDL rats, and the Akt/Nrf2 pathway plays a vital role in promoting the angiogenic related functions of BM-MSCs, which could be a potent contributor to pulmonary angiogenesis in HPS.