A low-cost, wireless, 4-channel EEG measurement system used in virtual reality environments.

The combination of Virtual Reality (VR) technology and Electroencephalography (EEG) measurements has shown tremendous potential in the fields of psychology and neuroscience research. However, the majority of EEG measurement devices currently available are expensive, bulky, uncomfortable to wear, and difficult to integrate with VR headsets. These limitations have hindered the development of related research fields. This study describes a low-cost (60.07 USD), small-sized, wireless, high-precision, low-power consumption 4-channel EEG measurement system (NeuroVista) for frontal area EEG measurements, which can be used with a VR headset, enabling EEG measurements in VR environments. The system has an input-referred noise of less than 0.9480 µVrms, a common mode rejection ratio of over 96 dB, a measurement resolution of less than 0.1 µV, a bandwidth of 0.5 âˆ¼ 45 Hz, and works at a sampling rate of 250 Hz. It also supports metal dry electrodes and includes a built-in analog bandpass filter, right-leg drive circuit, and built-in digital lowpass filter and notch filter, which can reduce noise during measurement. Researchers can reconstruct the electrode system to measure regions of interest according to their needs.

CIRP attenuates acute kidney injury after hypothermic cardiovascular surgery by inhibiting PHD3/HIF-1α-mediated ROS-TGF-ß1/p38 MAPK activation and mitochondrial apoptotic pathways.

BACKGROUND: The ischemia-reperfusion (IR) environment during deep hypothermic circulatory arrest (DHCA) cardiovascular surgery is a major cause of acute kidney injury (AKI), which lacks preventive measure and treatment. It was reported that cold inducible RNA-binding protein (CIRP) can be induced under hypoxic and hypothermic stress and may have a protective effect on multiple organs. The purpose of this study was to investigate whether CIRP could exert renoprotective effect during hypothermic IR and the potential mechanisms. METHODS: Utilizing RNA-sequencing, we compared the differences in gene expression between Cirp knockout rats and wild-type rats after DHCA and screened the possible mechanisms. Then, we established the hypothermic oxygen-glucose deprivation (OGD) model using HK-2 cells transfected with siRNA to verify the downstream pathways and explore potential pharmacological approach. The effects of CIRP and enarodustat (JTZ-951) on renal IR injury (IRI) were investigated in vivo and in vitro using multiple levels of pathological and molecular biological experiments. RESULTS: We discovered that Cirp knockout significantly upregulated rat Phd3 expression, which is the key regulator of HIF-1α, thereby inhibiting HIF-1α after DHCA. In addition, deletion of Cirp in rat model promoted apoptosis and aggravated renal injury by reactive oxygen species (ROS) accumulation and significant activation of the TGF-ß1/p38 MAPK inflammatory pathway. Then, based on the HK-2 cell model of hypothermic OGD, we found that CIRP silencing significantly stimulated the expression of the TGF-ß1/p38 MAPK inflammatory pathway by activating the PHD3/HIF-1α axis, and induced more severe apoptosis through the mitochondrial cytochrome c-Apaf-1-caspase 9 and FADD-caspase 8 death receptor pathways compared with untransfected cells. However, silencing PHD3 remarkably activated the expression of HIF-1α and alleviated the apoptosis of HK-2 cells in hypothermic OGD. On this basis, by pretreating HK-2 and rats with enarodustat, a novel HIF-1α stabilizer, we found that enarodustat significantly mitigated renal cellular apoptosis under hypothermic IR and reversed the aggravated IRI induced by CIRP defect, both in vitro and in vivo. CONCLUSION: Our findings indicated that CIRP may confer renoprotection against hypothermic IRI by suppressing PHD3/HIF-1α-mediated apoptosis. PHD3 inhibitors and HIF-1α stabilizers may have clinical value in renal IRI.

[Multiresolution discrete optimization registration method of ultrasound and magnetic resonance images based on key points].

The registration of preoperative magnetic resonance (MR) images and intraoperative ultrasound (US) images is very important in the planning of brain tumor surgery and during surgery. Considering that the two-modality images have different intensity range and resolution, and the US images are degraded by lots of speckle noises, a self-similarity context (SSC) descriptor based on local neighborhood information was adopted to define the similarity measure. The ultrasound images were considered as the reference, the corners were extracted as the key points using three-dimensional differential operators, and the dense displacement sampling discrete optimization algorithm was adopted for registration. The whole registration process was divided into two stages including the affine registration and the elastic registration. In the affine registration stage, the image was decomposed using multi-resolution scheme, and in the elastic registration stage, the displacement vectors of key points were regularized using the minimum convolution and mean field reasoning strategies. The registration experiment was performed on the preoperative MR images and intraoperative US images of 22 patients. The overall error after affine registration was (1.57 ± 0.30) mm, and the average computation time of each pair of images was only 1.36 s; while the overall error after elastic registration was further reduced to (1.40 ± 0.28) mm, and the average registration time was 1.53 s. The experimental results show that the proposed method has prominent registration accuracy and high computational efficiency.

Investigation of myocardial protection during pediatric CPB: Practical experience in 100 Chinese hospitals.

Many measures have been proposed for myocardial protection in pediatric congenital heart surgeries, but little data is available for China. This study investigates myocardial protection strategies in pediatric cardiopulmonary bypass (CPB) throughout China. Online questionnaires were delivered to 100 hospitals in 27 provinces. The number of yearly on-pump pediatric cardiovascular surgeries in these hospitals varied greatly. About 91.0% of respondents believe that each surgery should have at least two perfusionists, while only 64.0% of hospitals actually met this requirement. For pediatric patients, crystalloid cardioplegia was more prevalent than blood-based cardioplegia. Histidine-tryptophan-ketoglutarate solution and St. Thomas crystalloid solution were dominant among crystalloid cardioplegia. Del Nido cardioplegia and St. Thomas blood-based cardioplegia ranked the top two in the popularity of blood-based cardioplegia. Dosages varied among different kinds of cardioplegia. In the choice of different cardioplegia, perfusionists mainly focused on myocardial protective effect and cost. Hypothermia of cardioplegia solution was maintained by ice buckets in 3/4 of the hospitals in this survey. In conclusion, the essence of myocardial protection management during pediatric CPB was cardiac arrest induced by cardioplegia under systemic hypothermia. However, there is no uniform standard for the type of cardioplegia, or dosages. Therefore, well-designed multicenter randomized controlled trials are warranted to provide tangible evidence for myocardial protection of cardioplegia in pediatric CPB.

The lower threshold of hypothermic oxygen delivery to prevent neonatal acute kidney injury.

BACKGROUND: Oxygen delivery during cardiopulmonary bypass (CPB) is closely related to postoperative acute kidney injury (AKI). The value of critical indexed oxygen delivery (DO2i) is a key indicator to reflect oxygen supply in cardiovascular surgery. However, the target DO2i value for neonates undergoing hypothermic CPB remains unclear. METHODS: One hundred and twenty-six consecutive newborns (≤28 days) undergoing arterial switch operations were retrospectively divided into two groups according to AKI occurrence. Baseline characteristics, intraoperative variables, and clinical outcomes were collected. Multivariate logistic regression analysis and receiver-operating characteristic curve were performed to investigate the association between DO2i and AKI. RESULTS: Neonates in the no-AKI group (n = 67) had significantly higher nadir bypass flow and DO2i during the hypothermic phase compared with the AKI group (n = 59). AKI group had remarkably higher incidences of hepatic dysfunction and peritoneal dialysis requirement compared with newborns without AKI. Mixed venous oxygen saturation (SvO2) was comparable between the two groups. Base excess (BE)(P = 0.011) value during the hypothermic phase of the AKI group was higher than the no-AKI group. Multivariate analysis showed that hypothermic DO2i was negatively associated with AKI. The cut-off value of hypothermic DO2i was 269 mL min-1 m-2. CONCLUSIONS: The importance of hypothermic DO2i should be highlighted, even when SvO2 was satisfactory. A lower threshold of DO2i > 269 mL min-1 m-2 may help protect neonates from the risk of postoperative AKI. IMPACT: The key message of our article is that the lower threshold of DO2i > 269 mL min-1 m-2 may help protect neonates from the risk of AKI after on-pump hypothermic cardiovascular surgery. The critical DO2i value for neonates undergoing hypothermic CPB remains unclear, and our study may add new evidence for this matter based on the 6-year experience of our center. In this study, the lowest critical value of DO2i in neonatal hypothermic CPB is determined for the first time, which provides a reference for intra-CPB management strategy to improve the postoperative outcomes of newborns.

Risk Factors and Long-Term Prognosis for Chylothorax After Total Cavopulmonary Connection in Children: A Retrospective Study From a Single Center.

Background: Chylothorax is a severe complication after total cavopulmonary connection (TCPC) in children. This study was performed to evaluate the incidence, risk factors, and short- and long-term prognosis for chylothorax. Methods: We retrospectively reviewed the electronic records of patients who underwent TCPC between January 2008 and December 2020 in Fuwai Hospital. Patients were divided into two groups based on the occurrence of post-operative chylothorax. Univariate and multivariate analyses were performed to identify risk factors, and long-term survival was estimated by the Kaplan-Meier method. Results: Of 386 patients included in our study, chylothorax occurred in 60 patients (15.5%). Compared with the non-chylothorax group, the prevalence of prolonged intensive care unit (ICU) stay (p = 0.000) and post-operative hospital stay (p = 0.000) were greater in patients with chylothorax. Post-operative adverse events in terms of infection (p = 0.002), ascites (p = 0.001), prolonged pleural effusion (p = 0.000), and diaphragmatic paralysis (p = 0.026) were more frequent in chylothorax patients. The median follow-up duration was 4.0 (2.0, 6.8) years. The chylothorax group had significantly lower survival rates at 1 year (92.4 vs. 99.3%, p < 0.001) and 10 years (84.6 vs. 91.6%, p < 0.001), respectively. Having a right dominant ventricle [odds ratio (OR) = 2.711, 95% confidence interval (CI) = 1.285-5.721, p = 0.009] and a higher peak central venous pressure (CVP) on post-operative day (POD) 0 (OR = 1.116, 95% CI = 1.011-1.233, p = 0.030) were the risk factors for the development of chylothorax after TCPC operation. Conclusion: The incidence of chylothorax in patients undergoing TCPC is lower than previously reported but is associated with poor early- and long-term survival. Having a right dominant ventricle and a higher peak CVP on POD 0 are the risk factors for chylothorax after TCPC operation.

Prediction of acute kidney injury in ICU with gradient boosting decision tree algorithms.

PURPOSE: To predict acute kidney injury (AKI) in a large intensive care unit (ICU) database. MATERIALS AND METHODS: A total of 30,020 ICU admissions with 17,222 AKI episodes were extracted from the Medical Information Mart from Intensive Care (MIMIC)-III database. These were randomly divided into a training set and an independent testing set in a ratio of 4:1. Data pertaining to demographics, admission information, vital signs, laboratory tests, critical illness scores, medications, comorbidities, and intervention measures were collected. Logistic regression, random forest, LightGBM, XGBoost, and an ensemble model was used for early prediction of AKI occurrence and important feature extraction. The SHAP analysis was adopted to reveal the impact of prediction for each feature. RESULTS: The ensemble model had the best overall performance for predicting AKI before 24 h, 48 h and 72 h. The F1 values were 0.915, 0.893, and 0.878, respectively. AUCs were 0.923, 0.903, and 0.895, respectively. CONCLUSIONS: Based on readily available electronic medical record (EMR) data, gradient boosting decision tree models are highly accurate at early AKI prediction in critically ill patients.

Comparable prognosis in different neonatal histidine-tryptophan-ketoglutarate dosage management.

BACKGROUND: Histidine-tryptophan-ketoglutarate (HTK) is a solution commonly used for organ transplantation. However, there is no certified fixed regimen for on-pump heart surgery in neonates. We aimed to retrospectively evaluate the outcomes related to different HTK dosages and to analyze the safety of high-dosage perfusion. METHODS: A total of 146 neonates who underwent on-pump heart surgery with single-shot HTK perfusion were divided into two groups according to HTK dosages: a standard-dose (SD) group (n = 63, 40 mL/kg < HTK ≤ 60 mL/kg) and a high-dose (HD) group (n = 83, HTK >60 mL/kg). Propensity score matching (PSM) was performed to control confounding bias. RESULTS: The SD group had a higher weight (3.7 ±â€Š0.4 vs. 3.4 ±â€Š0.4 kg, P < 0.0001), a lower proportion of complete transposition of the great artery (69.8% vs. 85.5%, P = 0.022), a lower cardiopulmonary bypass (CPB) time (123.5 [108.0, 136.0] vs. 132.5 [114.8, 152.5] min, P = 0.034), and a lower aortic x-clamp time (82.9 ±â€Š27.1 vs. 95.5 ±â€Š26.0 min, P = 0.005). After PSM, 44 patients were assigned to each group; baseline characteristics and CPB parameters between the two groups were comparable. There were no significant differences in peri-CPB blood product consumption after PSM (P > 0.05). The incidences of post-operative complications were not significantly different between the two groups. There were no significant differences in ventilation time, intensive care unit stay, and post-operative hospital stay (P > 0.05). Follow-up echocardiography outcomes at 1 month, 3 to 6 months, and 1 year showed that left ventricular ejection fraction and end-diastolic dimension were comparable between the two groups. CONCLUSIONS: In neonatal on-pump cardiac surgery patients, single-shot HD (>60 mL/kg) HTK perfusion had a comparable heart protection effect and short-term post-operative prognosis as standard dosage perfusion of 40 to 60 mL/kg. Thus, this study provides supporting evidence of the safety of HD HTK perfusion.

Contrast media exposure in the perioperative period confers no additional risk of acute kidney injury in infants and young children undergoing cardiac surgery with cardiopulmonary bypass.

BACKGROUND: Recently, there has been an interest in the temporal relationship between contrast exposure (CM) and cardiac surgery suggesting that a "double hit" on the kidney function in close succession increases the risk of acute kidney injury (AKI) after cardiac surgery. However, data from young children is limited. The purpose of this study was to retrospectively evaluate the effects of preoperative CM exposure on postoperative AKI in infant and young children patients and to further analyze the influence of exposure time interval. METHODS: Patients (age ≤ 3 years) who underwent diagnostic imaging within 14 days before on-pump cardiac surgery between 1 May 2017 and 31 May 2018 in Fuwai Hospital, Beijing, were analyzed. Kidney outcome was assessed according to Kidney Disease: Improving Global Outcomes creatinine-based criteria. RESULTS: One thousand four hundred pediatric patients (192 CM and 1,248 non-CM) were identified. Postoperative AKI occurred in 57 (29.7%) of the 192 patients who were exposed to CM. Following propensity score adjustment, no difference in risk for AKI was observed between the CM and non-CM groups (RR 1.142, 95% CI 0.916-1.424; P = 0.264). Multivariable logistic regression of the CM group indicated that independent predictors of postoperative AKI were lower weight, lower preoperative creatinine level, and longer CPB duration. Time interval between CM exposure and on-pump cardiac surgery was not significantly associated with increased risk of AKI (OR 0.853, 95% CI 0.265~2.747; P = 0.790). CONCLUSIONS: For pediatric patients who are soon to undergo on-pump cardiac procedures, there appears to be no need to hesitate in performing the diagnostic imaging investigations requiring CM, or delay CPB after CM exposure. These patients may benefit from increased diagnostic utility without increasing their risk of postoperative AKI.

Outcomes and factors associated with early mortality in pediatric postcardiotomy veno-arterial extracorporeal membrane oxygenation.

Mortality and morbidity of children received veno-arterial extracorporeal membrane oxygenation (VA-ECMO) support after cardiac surgery remain high despite remarkable advances in medical management and devices. The purpose of this study was to describe outcomes and risk factors of applying VA-ECMO in the surgical pediatric population. We retrospectively analyzed 85 consecutive pediatric patients (aged <18 years) who received postcardiotomy VA-ECMO from January 2010 to December 2018. Median (IQR) age at ECMO implantation in this cohort was 12.7 (6.4, 43.2) months, median weight was 8.5 (6.0, 12.8) kg, mean ECMO duration was 143.2 ± 81.6 hours and mean hospital length of stay was 48.4 ± 32.4 days. Seventy-five patients (88.2%) were indicated for postcardiotomy cardiogenic shock. The successful ECMO weaning rate was 70.6% and in-hospital mortality was 52.9%. The most common diagnosis was transposition of great arteries (n = 18, 21.2%), while acute kidney injury occurred most often (n = 64, 75.3%). Multivariate logistic regression analysis showed that thrombocytopenia, hemolysis, and nosocomial infection were positively correlated with in-hospital mortality. Multivariate Cox proportional hazard regression analysis presented that thrombocytopenia significantly increased the 180-day mortality in patients with successful weaning. Therefore, multiple factors had adverse effects on prognosis. Patient selection and procedures from ECMO implantation to weaning need to be closely monitored and performed in a timely manner to improve outcome.

Identifying subtypes of mild cognitive impairment from healthy aging based on multiple cortical features combined with volumetric measurements of the hippocampal subfields.

BACKGROUND: Mild cognitive impairment (MCI) is subtle cognitive decline with an estimated 10-15% yearly conversion rate toward Alzheimer's disease (AD). It remains unexplored in brain cortical association areas in different lobes and its changes with progression and conversion of MCI. METHODS: Brain structural magnetic resonance (MR) images were collected from 102 stable MCI (sMCI) patients. One hundred eleven were converted MCI (cMCI) patients, and 109 were normal control (NC). The cortical surface features and volumes of subcortical hippocampal subfields were calculated using the FreeSurfer software, followed by an analysis of variance (ANOVA) model, to reveal the differences between the NC-sMCI, NC-cMCI, and sMCI-cMCI groups. Afterward, the support vector machine-recursive feature elimination (SVM-RFE) method was applied to determine the differences between the groups. RESULTS: The experimental results showed that there were progressive degradations in either range or degree of the brain structure from NC to sMCI, and then to cMCI. The SVM classifier obtained accuracies with 64.62%, 78.96%, and 70.33% in the sMCI-NC, cMCI-NC, and cMCI-sMCI groups, respectively, using the volumes of hippocampal subfields independently. The combination of the volumes from the hippocampal subfields and cortical measurements could significantly increase the performance to 71.86%, 84.64%, and 76.86% for the sMCI-NC, cMCI-NC, and cMCI-sMCI classifications, respectively. Also, the brain regions corresponding to the dominant features with strong discriminative power were widely located in the temporal, frontal, parietal, olfactory cortexes, and most of the hippocampal subfields, which were associated with cognitive decline, memory impairment, spatial navigation, and attention control. CONCLUSIONS: The combination of cortical features with the volumes of hippocampal subfields could supply critical information for MCI detection and its conversion.

Diffusion MRI Derived per Area Vessel Density as a Surrogate Biomarker for Detecting Viral Hepatitis B-Induced Liver Fibrosis: A Proof-of-Concept Study.

Liver vessel density can be evaluated by an imaging biomarker diffusion-derived vessel density (DDVD): DDVD/area(b0b2) = Sb0/ROIarea0 - Sb2/ROIarea2, where Sb0 and Sb2 refer to the liver signal when b is 0 or 2 (s/mm2); ROIarea0 and ROIarea2 refer to the region of interest (ROI) on b = 0 or 2 images; and Sb2 may be replaced by Sb15 (b = 15). This concept was validated in this study. Liver diffusion images were acquired at 1.5 T. For a scan-rescan repeatability study of six subjects, b values of 0 and 2 were used. The validation study was composed of 26 healthy volunteers and 19 consecutive suspected chronic viral hepatitis B patients, and diffusion images with b values of 0, 2, 15, 20, 30, 45, 50, 60, 80, 100, 200, 300, 600, and 800 were acquired. Four patients did not have liver fibrosis, and the rest were four stage 1, three stage 2, four stage 3, and one stage 4 patients, respectively. The intraclass correlation coefficient for repeatability was 0.994 for DDVD/area(Sb0Sb2) and 0.978 for DDVD/area(Sb0Sb15). In the validation study, DDVD/area(Sb0Sb2) and area(Sb0Sb15) were 14.80 ± 3.06 and 26.58 ± 3.97 for healthy volunteers, 10.51 ± 1.51 and 20.15 ± 2.21 for stage 1-2 fibrosis patients, and 9.42 ± 0.87 and 19.42 ± 1.89 for stage 3-4 fibrosis patients. For 16 patients where IVIM analysis was performed, a combination of DDVD/area, PF, and Dfast achieved the best differentiation for nonfibrotic livers and fibrotic livers. DDVD/area were weakly correlated with PF or Dfast. Both DDVD/area(Sb0Sb2) and area(Sb0Sb15) are useful imaging biomarkers to separate fibrotic and nonfibrotic livers, with fibrotic livers having lower measurements.

Perioperative blood product transfusion of two different perfusion strategies on pediatric patients undergoing aortic arch surgery.

Simple regional cerebral perfusion (SRCP) or cerebro-myocardial perfusion (CMP) is selectively used in one-stage complex aortic arch malformation repair. This analysis was performed to investigate the effect of CMP and SRCP on perioperative blood product consumption, and to evaluate whether these two strategies have different effects on the clinical outcomes. A retrospective analysis of 284 children with complicated aortic malformation from January 2010 to June 2018 was performed. The overall cohort was divided into SRCP group (n = 202) and CMP group (n = 82). A comprehensive comparison of perioperative blood product consumption-related indexes was performed. Cardiopulmonary bypass time, cardiac arrest time, cooling, and rewarming time in the CMP group were significantly shorter than those in the SRCP group (P < .05). Chest tube time was 3.82 ± 1.33 days in the SRCP group compared to 3.42 ± 0.97 days in the CMP group (P = .005). Moreover, intraoperative platelet (PLT) transfusion volume (mL/kg) and rate (%) were significantly lower in the CMP group (P < .001). Multivariate regression analysis found that intraoperative PLT transfusion was significantly negatively correlated with CMP management [OR = 0.237 (0.110-0.507), P < .001] and CPB time was independently associated with delayed chest tube removal (>3 days) [OR = 1.010 (1.001-1.020), P = .031]. In-hospital mortality and early postoperative adverse events were not significantly different between the two groups. In children with on-pump complex aortic arch surgeries, CMP is more preferable than SRCP in blood protection. However, overall prognosis was not remarkably different between these two perfusion groups. They are both safe and feasible.

High performance of intravoxel incoherent motion diffusion MRI in detecting viral hepatitis-b induced liver fibrosis.

BACKGROUND: Recently a small cohort study demonstrated that intravoxel incoherent motion (IVIM) diffusion MRI can detect early stage liver fibrosis. Using modified IVIM data acquisition parameters, the current study aims to confirm this finding. METHODS: Twenty-six healthy volunteers, three patients of chronic viral hepatitis-b but without fibrosis and one mild liver steatosis subject, and 12 viral hepatitis-b patients with fibrosis (stage 1-2=7, stage 3-4=5) were included in this study. With a 1.5-T MR scanner and respiration-gating, IVIM diffusion imaging was acquired using a single-shot echo-planar sequence with a b-value series of 2, 0, 1, 15, 20, 30, 45, 50, 60, 80, 100, 200, 300, 600, 800 s/mm2. Signal measurement was performed on right liver parenchyma. The first three very low b-values were excluded to improve the curve fitting stability, and bi-exponential segmented fitting was performed using the 12 b-values of 15~800 s/mm2. Both threshold b-values of 60 s/mm2 and 200 s/mm2 were tested. With a 3-dimensional tool, Dslow (D), PF (f) and Dfast (D*) values were placed along the x-axis, y-axis, and z-axis, and a plane was defined to separate healthy volunteers from liver fibrosis patients. RESULTS: Threshold b-value of 60 s/mm2 was preferred over 200 s/mm2 for separating healthy volunteers and liver fibrosis patients. The IVIM measures of the four patients without fibrosis resembled those of healthy volunteers. When threshold b-value =60 s/mm2 was applied, PF (PF <6.49%) could differentiate healthy livers and all fibrotic livers with 100% sensitivity and specificity. For the patients' measurement, PF and Dfast were highly correlated with a Pearson correlation coefficient r of 0.865 (P<0.001); while the correlations between slow diffusion compartment (Dslow) and fast diffusion compartment (Dfast or PF) were not statistically significant. CONCLUSIONS: This study confirms previous report that IVIM diffusion MRI has high diagnostic performance in detecting viral hepatitis-b induced liver fibrosis.

Risk factors of prolonged ventilation in adults after atrioventricular septal defect operation / 中国胸心血管外科临床杂志

@#Objective To investigate the risk factors of prolonged postoperative mechanical ventilation for adult patients with atrioventricular septal defect (AVSD). Methods We retrospectively analyzed the clinical data of 76 patients with AVSD aged more than 18 years in our hospital from January 1, 2011 to December 31, 2017. The patients ventilated longer than 24 hours were described as a prolonged ventilation group (n=27) and the others as a normal group (n=49). There were 9 males and 18 females aged 32.22±9.64 years in the prolonged ventilation group, and 16 males and 33 females aged 35.98±11.34 years in the normal group. Perioperative variables between the two groups were compared and selected, and then analyzed by logistic regression analysis. Results The result of univariate analysis showed that there was a statistical difference in weight, preoperative pulmonary artery systolic pressure, duration of cardiopulmonary bypass, the level of postoperative platelet, hemoglobin, blood glucose, lactic acid and serum creatinine, postoperative maximum heart rate and postoperative infection rate between the prolonged ventilated group and the normal group. Multivarable logistic regression showed that preoperative pulmonary artery hypertension (OR=1.056, 95%CI 1.005 to 1.110, P=0.030), prolonged duration of cardiopulmonary bypass (OR=1.036, 95%CI 1.007 to 1.066, P=0.016) and the low postoperative hemoglobin level (OR=0.874, 95%CI 0.786 to 0.973, P=0.014) were the risk factors of prolonged postoperative mechanical ventilation. Conclusion Preoperative pulmonary artery hypertension, long duration of cardiopulmonary bypass and postoperative anaemia are the risk factors associated with prolonged postoperative mechanical ventilation.

Research progress of mast cells in the mechanism of intestinal injury caused by deep hypothermic circulatory arrest / 中国胸心血管外科临床杂志

@#Deep hypothermic circulatory arrest (DHCA) is an important assistant technique for complex cardiac surgery, which creates convenient operating conditions for surgery, and is also one of the measures to protect the brain during operation. However, the complications caused by this technique cannot be ignored, and it should be noticed that the occurrence of intestinal injury is relatively insidious, but brings great pain to patients and significantly reduces the quality of life after operation. Studies have shown that intestinal ischemia-reperfusion injury is induced by DHCA. It causes mast cells to activate and release many inflammatory mediators that destroy the intestinal mucosal epithelium barrier, and eventually lead to intestinal injury. This article reviewed the research progress of mast cells in the mechanism of DHCA-induced intestinal injury.

Discrimination and conversion prediction of mild cognitive impairment using convolutional neural networks.

BACKGROUND: Recently, studies have demonstrated that machine learning techniques, particularly cutting-edge deep learning technology, have achieved significant progression on the classification of Alzheimer's disease (AD) and its prodromal phase, mild cognitive impairment (MCI). Moreover, accurate prediction of the progress and the conversion risk from MCI to probable AD has been of great importance in clinical application. METHODS: In this study, the baseline MR images and follow-up information during 3 years of 150 normal controls (NC), 150 patients with stable MCI (sMCI) and 157 converted MCI (cMCI) were collected from the Alzheimer's Disease Neuroimaging Initiative (ADNI). The deep convolutional neural networks (CNNs) were adopted to distinguish different stages of MCI from the NC group, and predict the conversion time from MCI to AD. Two CNN architectures including GoogleNet and CaffeNet were explored and evaluated in multiple classifications and estimations of conversion risk using transfer learning from pre-trained ImageNet (via fine-tuning) and five-fold cross-validation. A novel data augmentation approach using random views aggregation was applied to generate abundant image patches from the original MR scans. RESULTS: The GoogleNet acquired accuracies with 97.58%, 67.33% and 84.71% in three-way discrimination among the NC, sMCI and cMCI groups respectively, whereas the CaffeNet obtained promising accuracies of 98.71%, 72.04% and 92.35% in the NC, sMCI and cMCI classifications. Furthermore, the accuracy measures of conversion risk of patients with cMCI ranged from 71.25% to 83.25% in different time points using GoogleNet, whereas the CaffeNet achieved remarkable accuracy measures from 95.42% to 97.01% in conversion risk prediction. CONCLUSIONS: The experimental results demonstrated that the proposed methods had prominent capability in classification among the 3 groups such as sMCI, cMCI and NC, and exhibited significant ability in conversion risk prediction of patients with MCI.

Corrigendum: Conversion Discriminative Analysis on Mild Cognitive Impairment Using Multiple Cortical Features from MR Images.

[This corrects the article on p. 146 in vol. 9, PMID: 28572766.].

Conversion Discriminative Analysis on Mild Cognitive Impairment Using Multiple Cortical Features from MR Images.

Neuroimaging measurements derived from magnetic resonance imaging provide important information required for detecting changes related to the progression of mild cognitive impairment (MCI). Cortical features and changes play a crucial role in revealing unique anatomical patterns of brain regions, and further differentiate MCI patients from normal states. Four cortical features, namely, gray matter volume, cortical thickness, surface area, and mean curvature, were explored for discriminative analysis among three groups including the stable MCI (sMCI), the converted MCI (cMCI), and the normal control (NC) groups. In this study, 158 subjects (72 NC, 46 sMCI, and 40 cMCI) were selected from the Alzheimer's Disease Neuroimaging Initiative. A sparse-constrained regression model based on the l2-1-norm was introduced to reduce the feature dimensionality and retrieve essential features for the discrimination of the three groups by using a support vector machine (SVM). An optimized strategy of feature addition based on the weight of each feature was adopted for the SVM classifier in order to achieve the best classification performance. The baseline cortical features combined with the longitudinal measurements for 2 years of follow-up data yielded prominent classification results. In particular, the cortical thickness produced a classification with 98.84% accuracy, 97.5% sensitivity, and 100% specificity for the sMCI-cMCI comparison; 92.37% accuracy, 84.78% sensitivity, and 97.22% specificity for the cMCI-NC comparison; and 93.75% accuracy, 92.5% sensitivity, and 94.44% specificity for the sMCI-NC comparison. The best performances obtained by the SVM classifier using the essential features were 5-40% more than those using all of the retained features. The feasibility of the cortical features for the recognition of anatomical patterns was certified; thus, the proposed method has the potential to improve the clinical diagnosis of sub-types of MCI and predict the risk of its conversion to Alzheimer's disease.