Theoretical Exploration of Flexible Transmitter Model

Neural network models generally involve two important components, i.e., network architecture and neuron model. Although there are abundant studies about network architectures, only a few neuron models have been developed, such as the MP neuron model developed in 1943 and the spiking neuron model developed in the 1950s. Recently, a new bio-plausible neuron model, flexible transmitter (FT) model (Zhang and Zhou, 2021), has been proposed. It exhibits promising behaviors, particularly on temporal-spatial signals, even when simply embedded into the common feedforward network architecture. This article attempts to understand the properties of the FT network (FTNet) theoretically. Under mild assumptions, we show that: 1) FTNet is a universal approximator; 2) the approximation complexity of FTNet can be exponentially smaller than those of commonly used real-valued neural networks with feedforward/recurrent architectures and is of the same order in the worst case; and 3) any local minimum of FTNet is the global minimum, implying that it is possible to identify global minima by local search algorithms.

Weakly Supervised AUC Optimization: A Unified Partial AUC Approach

Since acquiring perfect supervision is usually difficult, real-world machine learning tasks often confront inaccurate, incomplete, or inexact supervision, collectively referred to as weak supervision. In this work, we present WSAUC, a unified framework for weakly supervised AUC optimization problems, which covers noisy label learning, positive-unlabeled learning, multi-instance learning, and semi-supervised learning scenarios. Within the WSAUC framework, we first frame the AUC optimization problems in various weakly supervised scenarios as a common formulation of minimizing the AUC risk on contaminated sets, and demonstrate that the empirical risk minimization problems are consistent with the true AUC. Then, we introduce a new type of partial AUC, specifically, the reversed partial AUC (rpAUC), which serves as a robust training objective for AUC maximization in the presence of contaminated labels. WSAUC offers a universal solution for AUC optimization in various weakly supervised scenarios by maximizing the empirical rpAUC. Theoretical and experimental results under multiple settings support the effectiveness of WSAUC on a range of weakly supervised AUC optimization tasks.

[Relation factor analysis for the short-term preservation of ipsilateral renal function after partial nephrectomy]

Objectives: To analyze the factors relative to the short-term preservation of ipsilateral renal function after partial nephrectomy. Methods: The clinical data of 83 patients who were treated with partial nephrectomy from December 2014 to December 2019 in the Department of Urology, Sun Yat-sen University Cancer Center were retrospectively analyzed. There were 54 males and 29 females, aging (M (IQR)) 49 (17) years (range: 27 to 74 years). The ischemia time in operation was 25 (18) minutes (range: 10 to 67 minutes). Emission computed tomography scan and CT scan were performed before (within 1 month) and after (3 to 12 months) surgery. The volume of the ipsilateral and contralateral kidney was measured on the basis of preoperative and postoperative CT scans. The glomerular filtration rate (GFR) specifically in each kidney was estimated by emission computed tomography. Recovery from ischemia is determined by the formula: GFR preservation/volume saved×100%. Linear regression was used to explore the factors ralative to the short-term preservation of ipsilateral renal function after partial nephrectomy. Results: The GFR preservation of the ipsilateral kidney was 80.9 (25.2) % (range: 31.0% to 109.4%). The volume loss of the kidney resulted in a decrease of 12.0% (5.8 ml/(min×1.96 m2)) of GFR, while the ischemic injury resulted in a decrease of 6.5% (2.5 ml/(min×1.96 m2)) of GFR. The volume saved from the ipsilateral kidney was 87.1 (12.9) % (range: 27.0% to 131.7%). Recovery from ischemia was 93.5 (17.5) % (range:44.3% to 178.3%). In multivariate analysis, GFR preservation of the ipsilateral kidney was significantly correlated with the volume saved of the ipsilateral kidney (β=0.383, 95%CI: 0.144 to 0.622, P=0.002). It was not related to the ischemia time (β=0.046, 95%CI:-0.383 to 0.475, P=0.831). Conclusion: In the condition of limited ischemic time, in the short term ipsilateral renal function after partial nephrectomy is mainly determined by the loss of kidney volume, while ischemic injury only plays a minor role.

[Long-term survival analysis of 1 367 patients treated with radical nephrectomy from a single center]

Objective: To report the long-term survival of renal cell carcinoma (RCC) patients treated with radical nephrectomy in Sun Yat-sen University Cancer Center. Methods: We retrospectively analyzed the clinical, pathological and follow-up records of 1 367 non-metastatic RCC patients treated with radical nephrectomy from 1999 to 2020 in this center. The primary endpoint of this study was overall survival rate. Survival curves were estimated using the Kaplan-Meier method, and group differences were compared through Log-rank test. Univariate and multivariate Cox analysis were fit to determine the clinical and pathological features associated with overall survival rate. Results: A total of 1 367 patients treated with radical nephrectomy with complete follow-up data were included in the study. The median follow-up time was 52.6 months, and 1 100 patients survived and 267 died, with the median time to overall survival not yet reached. The 5-year and 10-year overall survival rates were 82.8% and 74.9%, respectively. The 5-year and 10-year overall survival rates of Leibovich low-risk patients were 93.3% and 88.2%, respectively; of Leibovich intermediate-risk patients were 82.2% and 72.3%, respectively; and of Leibovich high-risk patients were 50.5% and 30.2%, respectively. There were significant differences in the long-term survival among the three groups (P<0.001). The 10-year overall survival rates for patients with pT1, pT2, pT3 and pT4 RCC were 83.2%, 73.6%, 55.0% and 31.4%, respectively. There were significant differences among pT1, pT2, pT3 and pT4 patients(P<0.001). The 5-year and 10-year overall survival rates of patients with lymph node metastasis were 48.5% and 35.6%, respectively, and those of patients without lymph node metastasis were 85.1% and 77.5%, respectively. There was significant difference in the long-term survival between patients with lymph node metastasis and without lymph node metastasis. The 10-year overall survival rate was 96.2% for nuclear Grade 1, 81.6% for nuclear Grade 2, 60.5% for nuclear Grade 3, and 43.4% for nuclear Grade 4 patients. The difference was statistically significant. There was no significant difference in the long-term survival between patients with localized renal cancer (pT1-2N0M0) who underwent open surgery and minimally invasive surgery (10-year overall survival rate 80.5% vs 85.6%, P=0.160). Multivariate Cox analysis showed that age≥55 years (HR=2.11, 95% CI: 1.50-2.96, P<0.001), T stage(T3+ T4 vs T1a: HR=2.37, 95% CI: 1.26-4.46, P=0.008), local lymph node metastasis (HR=3.04, 95%CI: 1.81-5.09, P<0.001), nuclear grade (G3-G4 vs G1: HR=4.21, 95%CI: 1.51-11.75, P=0.006), tumor necrosis (HR=1.66, 95% CI: 1.17-2.37, P=0.005), sarcomatoid differentiation (HR=2.39, 95% CI: 1.31-4.35, P=0.005) and BMI≥24kg/m(2) (HR=0.56, 95%CI: 0.39-0.80, P=0.001) were independent factors affecting long-term survival after radical nephrectomy. Conclusions: The long-term survival of radical nephrectomy in patients with renal cell carcinoma is satisfactory. Advanced age, higher pathological stage and grade, tumor necrosis and sarcomatoid differentiation were the main adverse factors affecting the prognosis of patients. Higher body mass index was a protective factor for the prognosis of patients.

[Establishment and validation of a novel nomogram to predict overall survival after radical nephrectomy]

Objective: To establish a nomogram prognostic model for predicting the 5-, 10-, and 15-year overall survival (OS) of non-metastatic renal cell carcinoma patients managed with radical nephrectomy (RN), compare the modelled results with the results of pure pathologic staging, the Karakiewicz nomogram and the Mayo Clinic Stage, Size, Grade, and Necrosis (SSIGN) score commonly used in foreign countries, and stratify the patients into different prognostic risk subgroups. Methods: A total of 1 246 non-metastatic renal cell carcinoma patients managed with RN in Sun Yat-sen University Cancer Center (SYSUCC) from 1999 to 2020 were retrospectively analyzed. Multivariate Cox regression analysis was used to screen the variables that influence the prognosis for nomogram establishment, and the bootstrap random sampling was used for internal validation. The time-receiver operating characteristic curve (ROC), the calibration curve and the clinical decision curve analysis (DCA) were applied to evaluate the nomogram. The prediction efficacy of the nomogram and that of the pure pathologic staging, the Karakiewicz nomogram and the SSIGN score was compared through the area under the curve (AUC). Finally, patients were stratified into different risk subgroups according to our nomogram scores. Results: A total of 1 246 patients managed with RN were enrolled in this study. Multivariate Cox regression analysis showed that age, smoking history, pathological nuclear grade, sarcomatoid differentiation, tumor necrosis and pathological T and N stages were independent prognostic factors for RN patients (all P<0.05). A nomogram model named SYSUCC based on these factors was built to predict the 5-, 10-, and 15-year survival rate of the participating patients. In the bootstrap random sampling with 1 000 iterations, all these factors occurred for more than 800 times as independent predictors. The Harrell's concordance index (C-index) of SYSUCC was higher compared with pure pathological staging [0.770 (95% CI: 0.716-0.823) vs 0.674 (95% CI: 0.621-0.728)]. The calibration curve showed that the survival rate as predicted by the SYSUCC model simulated the actual rate, while the clinical DCA showed that the SYSUCC nomogram has a benefit in certain probability ranges. In the ROC analysis that included 857 patients with detailed pathological nuclear stages, the nomogram had a larger AUC (5-/10-year AUC: 0.823/0.804) and better discriminating ability than pure pathological staging (5-/10-year AUC: 0.701/0.658), Karakiewicz nomogram (5-/10-year AUC: 0.772/0.734) and SSIGN score (5-/10-year AUC: 0.792/0.750) in predicting the 5-/10-year OS of RN patients (all P<0.05). In addition, the AUC of the SYSUCC nomogram for predicting the 15-year OS (0.820) was larger than that of the SSIGN score (0.709), and there was no statistical difference (P<0.05) between the SYSUCC nomogram, pure pathological staging (0.773) and the Karakiewicz nomogram (0.826). The calibration curve was close to the standard curve, which indicated that the model has good predictive performance. Finally, patients were stratified into low-, intermediate-, and high-risk subgroups (738, 379 and 129, respectively) according to the SYSUCC nomogram scores, among whom patients in intermediate- and high-risk subgroups had a worse OS than patients in the low-risk subgroup (intermediate-risk group vs. low-risk group: HR=4.33, 95% CI: 3.22-5.81, P<0.001; high-risk group vs low-risk group: HR=11.95, 95% CI: 8.29-17.24, P<0.001), and the high-risk subgroup had a worse OS than the intermediate-risk group (HR=2.63, 95% CI: 1.88-3.68, P<0.001). Conclusions: Age, smoking history, pathological nuclear grade, sarcomatoid differentiation, tumor necrosis and pathological stage were independent prognostic factors for non-metastasis renal cell carcinoma patients after RN. The SYSUCC nomogram based on these independent prognostic factors can better predict the 5-, 10-, and 15-year OS than pure pathological staging, the Karakiewicz nomogram and the SSIGN score of patients after RN. In addition, the SYSUCC nomogram has good discrimination, agreement, risk stratification and clinical application potential.

[Clinical effects of free anterolateral thigh perforator flap pedicled with descending genicular artery in repairing wounds after lower leg limb-sparing surgery]

Objective: To explore the clinical effects of free anterolateral thigh perforator flap pedicled with descending genicular artery in repairing wounds after lower leg limb-sparing surgery. Methods: A retrospective observational study was conducted. From January 2019 to June 2021, 12 patients with wounds after lower leg limb-sparing surgery who met the inclusion criteria were admitted to Suzhou Ruihua Orthopedic Hospital, including 6 males and 6 females, aged 17 to 74 years, with original wound area ranging from 17 cm×9 cm to 40 cm×15 cm. Five patients had infection in wounds. The wounds were all repaired by free anterolateral thigh perforator flap from contralateral thigh, with area of 18 cm×10 cm to 37 cm×9 cm. The artery of flap was anastomosed with the descending genicular artery, and the wounds in donor areas were sutured directly. Seven patients were transplanted with split-thickness skin grafts from the contralateral thigh to cover the remaining wounds that can not be covered by flap and the wounds in donor areas were covered with gauze. During the operation, the types of perforating branch carried by flap and the types of arteries and veins in recipient areas were recorded. The survival and occurrence of vascular crisis of flap, the survival of skin graft, the wound healing in donor and recipient areas, and the length of hospital stay after flap transplant surgery were recorded. During follow-up, the color and texture of flap, reinfection in lower leg, and fracture healing were recorded. At the last follow-up, the limb salvage function of patients was evaluated according to the functional evaluation criteria of Chen Zhongwei's amputated limb replantation. Results: The types of perforating branches carried by flaps were as follows: 6 cases of only carrying the descending branch of the lateral circumflex femoral artery, 3 cases of only carrying the oblique branch of the lateral circumflex femoral artery, and 3 cases of carrying the descending branch of the lateral circumflex femoral artery and oblique branch of the lateral circumflex femoral artery after internal pressurization anastomosis. The types of arteries in the recipient area of flap were as follows: one case of main trunk of the descending genicular artery, 8 cases of the saphenous branch of the descending genicular artery, and 3 cases of the articular branch of the descending genicular artery. The types of veins in the recipient area of flap were as follows: 8 cases of one accompanying vein of the descending genicular artery and one branch of the great saphenous vein, and 4 cases of two branches of the great saphenous vein. All the flaps survived without vascular crisis, and all the skin grafts also survived. The wounds in the donor and recipient areas were all healed. The length of hospital stay of patient after flap transplant surgery ranged from 13 to 79 days. During the follow-up of 6 to 23 months, the color and texture of flap were both good, with no infection in lower leg wound. Internal or external fixation were removed after fracture healing in 5 patients, and bone graft internal fixation was performed in 7 patients whose fractures were not healed after surgery and all the incisions healed without infection. At the last follow-up, the limb salvage effect of patients was evaluated as followings: excellent in 7 patients, good in 4 patients, and fair in one patient. Conclusions: Free anterolateral thigh flap pedicled with descending genicular artery can effectively repair the wounds after lower leg limb-sparing surgery and control infection with short length of hospital stay, while not increasing the risk of secondary injury of distal limb vessels. Thus, it can obtain satisfactory limb salvage effect which is worthy of clinical promotion.

[Efficacy of partial nephrectomy in patients with localized renal carcinoma: a 20-year experience of 2 046 patients in a single center]

Objectives: To analyze the long-term survival of patients with localized renal cell carcinoma after partical nephrectomy. Methods: The clinicopathological records and survival follow-up data of 2 046 patients with localized renal cell carcinoma, who were treated with partial nephrectomy from August 2001 to February 2021 in the Department of Urology, Sun Yat-sen University Cancer Center, were retrospectively analyzed. There were 1 402 males and 644 females, aged (M(IQR)) 51 (19) years (range: 6 to 86 years). The primary end point of this study was cancer-specific survival. Survival curves were estimated using the Kaplan-Meier method, and the difference test was performed by Log-rank test. Univariate and multivariate Cox analysis were fitted to determine factors associated with cancer-specific survival. Results: The follow-up time was 49.2 (48.0) months (range: 1 to 229 months), with 1 974 patients surviving and 72 dying. The median cancer-specific survival time has not yet been reached. The 5- and 10-year cancer specific survival rates were 97.0% and 91.2%, respectively. The 10-year cancer-specific survival rates for stage pT1a (n=1 447), pT1b (n=523) and pT2 (n=58) were 95.3%, 81.8%, and 81.7%, respectively. The 10-year cancer-specific survival rates of patients with nuclear grade 1 (n=226), 2 (n=1 244) and 3 to 4 (n=278) were 96.6%, 89.4%, and 85.5%, respectively. There were no significant differences in 5-year cancer-specific survival rates among patients underwent open, laparoscopic, or robotic surgery (96.7% vs. 97.1% vs. 97.5%, P=0.600). Multivariate analysis showed that age≥50 years (HR=3.93, 95%CI: 1.82 to 8.47, P<0.01), T stage (T1b vs. T1a: HR=3.31, 95%CI: 1.83 to 5.99, P<0.01; T2+T3 vs. T1a: HR=2.88, 95%CI: 1.00 to 8.28, P=0.049) and nuclear grade (G3 to 4 vs. G1: HR=2.81, 95%CI: 1.01 to 7.82, P=0.048) were independent prognostic factors of localized renal cell carcinoma after partial nephrectomy. Conclusions: The long-term cancer-specific survival rates of patients with localized renal cancer after partial nephrectomy are satisfactory. The type of operation (open, laparoscopic, or robotic) has no significant effect on survival. However, patients with older age, higher nuclear grade, and higher T stage have a lower cancer-specific survival rate. Grasping surgical indications, attaching importance to preoperative evaluation, perioperative management, and postoperative follow-up, could benefit achieving satisfactory long-term survival.

Analysis of risk factors for neurological symptoms in patients with purely hepatic Wilson's disease at diagnosis

OBJECTIVE

To analyze and explore the risk factors for neurological symptoms in patients with purely hepatic Wilson's disease (WD) at diagnosis.

METHODS

This retrospective study was conducted at the First Affiliated Hospital of the Guangdong Pharmaceutical University on 68 patients with purely hepatic WD aged 20.6 ± 7.2 years. The physical examinations, laboratory tests, color Doppler ultrasound of the liver and spleen, and magnetic resonance imaging (MRI) of the brain were performed.

RESULTS

The elevated alanine transaminase (ALT) and aspartate transaminase (AST) levels and 24-h urinary copper level were higher in the purely hepatic WD who developed neurological symptoms (NH-WD) group than those in the purely hepatic WD (H-WD) group. Adherence to low-copper diet, and daily oral doses of penicillamine (PCA) and zinc gluconate (ZG) were lower in the NH-WD group than those in the H-WD group. Logistic regression analysis showed that insufficient doses of PCA and ZG were associated with the development of neurological symptoms in patients with purely hepatic WD at diagnosis.

CONCLUSION

The development of neurological symptoms in patients with purely hepatic WD was closely associated with insufficient doses of PCA and ZG, and the inferior efficacy of copper-chelating agents. During the course of anti-copper treatment, the patient's medical status and the efficacy of copper excretion should be closely monitored.

Aqueous C-H aminomethylation of phenols by iodine catalysis

A transition-metal-free strategy regarding an iodine-sodium percarbonate catalysis to achieve the ortho-aminomethylation of phenols in aqueous media has been developed. This method can effectively broaden a wide range of phenols, tolerate sensitive functional groups, and achieve the late-stage functionalization of ten functional molecules that contain phenolic structures.

Linear structural features of Wilson's disease and its correlation with neurological symptoms

To measure the linear structure of the brain in patients with Wilson's disease (WD) and analyze its correlation with neurological symptoms. A total of 174 patients diagnosed with WD were enrolled. According to the type of clinical presentation, the patients with WD were divided into two groups: neurological (NWD) and hepatic (HWD). Sixty healthy volunteers were assigned to a control group. All patients with WD and healthy controls underwent brain magnetic resonance imaging (MRI). The severity of the neurological symptoms was assessed using the Burke Fahn Marsden Movement subscale (BFM-M). Linear brain measurements were performed using T1-weighted MRI scans of all the patients, and the correlation between these linear indices and BFM-M score was investigated. The Huckman index, third ventricle width, and sulcus width of the NWD group were significantly higher than those of the HWD and control groups (P < .05). The frontal horn index, ventricular index, and lateral ventricular body width index of the NWD group were significantly lower than those of the HWD and control groups (P < .05). The Huckman index and third ventricle width of the HWD group were higher than those of the control group (P < .05), whereas the body width index of the lateral ventricle was lower than that of the control group (P < .05). The BFM-M score correlated with the Huckman index (r = 0.29, P < .05), third ventricle width (r = 0.426, P < .001), and lateral ventricular body width index (r = -0.19, P < .05). This study demonstrated significant changes in the linear structure of patients with WD. Linear brain measurement analysis could be used as a potential method to assess the severity of neurological symptoms in WD.

Elderly onset of MELAS in a male: A case report

BACKGROUND

Mitochondrial encephalomyopathy with lactic acidosis and stroke-like episodes (MELAS) is one of the most common maternally inherited mitochondrial diseases which rarely affects elderly people.

CASE PRESENTATION

We reported the case of a 61-year-old male patient with MELAS. He was experiencing acute migraine-like headaches as the first symptoms. Laboratory data showed elevated lactate and creatine kinase levels. Brain magnetic resonance imaging (MRI) found a high signal intensity lesion in the left occipital-temporal-parietal lobe on diffusion-weighted imaging (DWI). Magnetic resonance angiography (MRA) revealed reversible vasoconstriction of the middle cerebral arteries and superficial temporal arteries. A muscle biopsy suggested minor muscle damage. A genetic study revealed a mitochondrial DNA A3243G mutation.

CONCLUSION

Elderly onset of MELAS is rare and easily misdiagnosed as an ischemic stroke. MELAS with the onset of stroke-like episodes should be considered in adult or elderly patients with imaging findings that are atypical for cerebral infarction. The use of multimodal MRI in the clinical diagnosis of MELAS could be extremely beneficial.

[Landscape and metastases of the lymph nodes in prostatic anterior fat pad at radical prostatectomy]

Objectives: To examine the landscape and metastases of the lymph nodes in prostatic anterior fat pad (PAFP) at radical prostatectomy (RP), and to describe the clinical characteristic of the patients with lymph node metastases in PAFP. Methods: The clinical and pathological data of 287 prostate cancer patients underwent RP from December 2019 to August 2021 in Department of Urology, Sun Yat-sen University Cancer Center were collected and analyzed retrospectively. All patients were male, aging (66±7) years (range: 42 to 83 years). The preoperative prostate-specific antigen (PSA) (M(IQR)) were 16.00(29.64) μg/L (range: 0.01 to 99.90 μg/L). There were 244 patients with localized or locally advanced prostate cancer and 43 patients with metastatic prostate cancer. All PAFP were dissected at RP routinely and were sent for pathologic analysis respectively. The PAFP was dissected from the prostate apex caudally toward the bladder neck and dissection extended to the joint of the prostate and the endopelvic fascia bilaterally. All the specimen of PAFP were examined and reported by subspecialty pathologists of genitourinary tumors. Statistical analysis was performed by Student t test, Wilcoxon rank-sum test, χ² test or Fisher exact test. Results: There were 8.0% (23/287) patients with lymph nodes in PAFP, 3.8% (11/287) patients with PAFP lymph node metastases. Pathologically upstaged occurred in 1 patient due to the PAFP lymph node as the solitary metastatic lesion. Patients with lymph node metastases in PAFP presented higher preoperative PSA (M(IQR): 48.2(73.0) μg/L vs. 15.4(26.5) μg/L, Z=3.158, P=0.002), clinical T stage and N stage (Z=2.977, P=0.003; Z=2.780, P=0.005) and preoperative Gleason score (Z=2.205, P=0.027). Conclusions: Routine dissection of PAFP at RP and separately pathological analysis may allow more lymph nodes and lymph node metastases detection. More accurate pathological N stage may be acquired and consequently may improve the survival of patients by offering more appropriate adjuvant or salvage therapy.

Prediction With Unpredictable Feature Evolution

Learning with feature evolution studies the scenario where the features of the data streams can evolve, i.e., old features vanish and new features emerge. Its goal is to keep the model always performing well even when the features happen to evolve. To tackle this problem, canonical methods assume that the old features will vanish simultaneously and the new features themselves will emerge simultaneously as well. They also assume that there is an overlapping period where old and new features both exist when the feature space starts to change. However, in reality, the feature evolution could be unpredictable, which means that the features can vanish or emerge arbitrarily, causing the overlapping period incomplete. In this article, we propose a novel paradigm: prediction with unpredictable feature evolution (PUFE) where the feature evolution is unpredictable. To address this problem, we fill the incomplete overlapping period and formulate it as a new matrix completion problem. We give a theoretical bound on the least number of observed entries to make the overlapping period intact. With this intact overlapping period, we leverage an ensemble method to take the advantage of both the old and new feature spaces without manually deciding which base models should be incorporated. Theoretical and experimental results validate that our method can always follow the best base models and, thus, realize the goal of learning with feature evolution.

Margin Distribution Analysis

Margin is an important concept in machine learning; theoretical analyses further reveal that the distribution of margin plays a more critical role than the minimum margin in generalization power. Recently, several approaches have achieved performance breakthroughs by optimizing the margin distribution, but their computational cost, which is usually higher than before, still hinders them to be widely applied. In this article, we propose margin distribution analysis (MDA), which optimizes the margin distribution more simply by maximizing the margin mean and minimizing the margin variance simultaneously. MDA is efficient and resistive to class-imbalance naturally, since its objective distinguishes the margin means of different classes and can be broken up into two linear equations. In practice, it can also cooperate with other frameworks such as reweight-minimization when facing complex circumstances with noise and outliers. Empirical studies validate the superiority of MDA in real-world data sets, and demonstrate that simple approaches can also perform competitively by optimizing margin distribution.

Open environment machine learning

Conventional machine learning studies generally assume close world scenarios where important factors of the learning process hold invariant. With the great success of machine learning, nowadays, more and more practical tasks, particularly those involving open world scenarios where important factors are subject to change, called open environment machine learning (Open ML) in this article, are present to the community. Evidently it is a grand challenge for machine learning turning from close world to open world. It becomes even more challenging since, in various big data tasks, data are usually accumulated with time, like streams, while it is hard to train the machine learning model after collecting all data as in conventional studies. This article briefly introduces some advances in this line of research, focusing on techniques concerning emerging new classes, decremental/incremental features, changing data distributions, varied learning objectives, and discusses some theoretical issues.

[Correlation between the pre-and post-operative sagittal parameters and the quality of life in patients with degenerative and isthmic spondylolisthesis]

Objective: To assess the relationship between health-related quality of life (HRQOL) and spinal sagittal parameters in patients with degenerative and isthmic spondylolisthesis before and after surgery, and to provide a biomechanical basis for improving the clinical prognosis of such patients. Methods: A retrospective analysis of 63 patients with lumbar spondylolisthesis who received lumbar fusion surgery in the Department of Spine Surgery, Tianjin Union Medical Center from December 2017 to June 2020 was carried out. There were 16 males and 47 females with a mean age of (59±8) years. Subgroup analyses were conducted based on disease type (degenerative lumbar spondylolisthesis (DS) and the isthmic spondylolisthesis (IS)) and HRQOL scores. Patients were evaluated post-operatively to observe the improvement of symptoms and quality of life. The relationship between operative related factors, HRQOL scores before and after surgery, and spino-pelvic sagittal parameters (including sagittal axis of the spine, lumbar lordosis angle, pelvic incidence angle, pelvic tilt angle (PT), sacral tilt angle, matching degree of pelvic incidence angle (PI) and lumbar lordosis angle (LL), lumbar 1 vertebra plumb line, upper lumbar curve, lower lumbar curve) in the two groups were analyzed. The correlation between the improvement of HRQOL scores and spino-pelvic sagittal parameters in the DS group and the IS group was analyzed and compared. Results: There were significant differences between postoperative HRQOL scores compared with those before the operation in both the DS and IS groups at three times of follow-up after the operation (all P<0.05). There was no difference in the last HRQOL score, the number of surgical segments, operation time and intraoperative blood loss between the two groups (all P>0.05). The parameters of PT and PI-LL in DS patients with VAS back pain score>3 and ≤3 were statistically different (13.7°±6.4° vs 26.6°±7.4°, 5.1°±8.2° vs 18.2°±13.1°, respectively, both P<0.05), similar results were obtained in IS patients (14.1°±6.9° vs 16.4°±8.7°, 2.9°±9.7° vs 6.8°±9.8°, respectively, both P<0.05). In addition, the parameters of PT and PI-LL between patients with ODI>20 and ≤20 were all statistically different in the two groups at the last follow-up after surgery (all P<0.05). The improvement of VAS back pain score in DS and IS groups was significantly related to the improvement of PT value, respectively (r=0.76, 0.78, both P<0.05). The PT, LL and PI-LL were significantly correlated with the ODI in the DS group (r=0.60, 0.62, 0.50, all P<0.05). There was also a correlation between the improvement of ODI and PT, LL and PI-LL in the IS group, respectively (r=0.22, 0.41, 0.76, all P<0.05). Conclusions: Certain correlation exists between the HRQOL and spinal sagittal parameters in patients with degenerative and isthmic spondylolisthesis before and after surgery. For the treatment of lumbar spondylolisthesis and improvement of quality of life, the primary goal is to reconstruct the matching degree of the lumbar lordosis angle and PI, and to reduce the PT value to the normal range by tilting the pelvis forward.

Heterogeneous Few-Shot Model Rectification With Semantic Mapping

There still involve lots of challenges when applying machine learning algorithms in unknown environments, especially those with limited training data. To handle the data insufficiency and make a further step towards robust learning, we adopt the learnware notion Z.-H. Zhou, "Learnware: On the future of machine learning," Front. Comput. Sci., vol. 10, no. 4 pp. 589-590, 2016 which equips a model with an essential reusable property-the model learned in a related task could be easily adapted to the current data-scarce environment without data sharing. To this end, we propose the REctiFy via heterOgeneous pRedictor Mapping (ReForm) framework enabling the current model to take advantage of a related model from two kinds of heterogeneous environment, i.e., either with different sets of features or labels. By Encoding Meta InformaTion (Emit) of features and labels as the model specification, we utilize an optimal transported semantic mapping to characterize and bridge the environment changes. After fine-tuning over a few labeled examples through a biased regularization objective, the transformed heterogeneous model adapts to the current task efficiently. We apply ReForm over both synthetic and real-world tasks such as few-shot image classification with either learned or pre-defined specifications. Experimental results validate the effectiveness and practical utility of the proposed ReForm framework.

Flexible Transmitter Network

Current neural networks are mostly built on the MP model, which usually formulates the neuron as executing an activation function on the real-valued weighted aggregation of signals received from other neurons. This letter proposes the flexible transmitter (FT) model, a novel bio-plausible neuron model with flexible synaptic plasticity. The FT model employs a pair of parameters to model the neurotransmitters between neurons and puts up a neuron-exclusive variable to record the regulated neurotrophin density. Thus, the FT model can be formulated as a two-variable, two-valued function, taking the commonly used MP neuron model as its particular case. This modeling manner makes the FT model biologically more realistic and capable of handling complicated data, even spatiotemporal data. To exhibit its power and potential, we present the flexible transmitter network (FTNet), which is built on the most common fully connected feedforward architecture taking the FT model as the basic building block. FTNet allows gradient calculation and can be implemented by an improved backpropagation algorithm in the complex-valued domain. Experiments on a broad range of tasks show that FTNet has power and potential in processing spatiotemporal data. This study provides an alternative basic building block in neural networks and exhibits the feasibility of developing artificial neural networks with neuronal plasticity.

Clinicopathological significance of primitive phenotypes in early gastric cancer with differentiated histology

Background

Certain gastric cancers exhibit some primitive phenotypes, which may indicate a high malignancy. In histologically differentiated early gastric cancer (EGC), the presence and the clinicopathological significance of the primitive phenotype remain unclear.

Methods

Using immunohistochemical staining we detected the expression of three primitive phenotypic markers SALL4, Glypican-3(GPC3), and AFP in whole tissue sections of differentiated EGC (gastrectomy specimens, n = 302). For those cases with primitive phenotypes, we analyzed their clinicopathological features and evaluated whether the criteria for endoscopic resection were met.

Results

We found that 9.3% (28/302) of all differentiated EGC cases have primitive phenotypes, and most of these cases (25/28) exhibit a histomorphology similar to conventional differentiated EGC. Patients with primitive phenotypes had a deeper invasion, a higher rate of ulcer and lymphatic invasion than cases without primitive phenotype. Moreover, patients with primitive phenotypes displayed a significantly higher frequency of LNM than those without (57.1% vs 8.8%, P < 0.001). Multivariate analysis revealed that presence of primitive phenotypes was an independent risk factor for LNM (P = 0.001, HR 6.977, 95% CI: 2.199–22.138). Interestingly, we found 2 cases with primitive phenotypes developed LNM, and they both met the expanded indications of endoscopic resection for differentiated EGC.

Conclusions

A small number of differentiated EGC have primitive phenotypes, which were closely related to LNM and were an independent risk factor for LNM. Given its highly aggressive behavior, differentiated EGC with primitive phenotypes should be evaluated with stricter criteria before endoscopic resection, or considered to give an additional surgical operation after endoscopic resection.

[Grading of tumor budding in intestinal-type early gastric adenocarcinoma and its role in assessing the risk of lymph node metastasis]

Objective: To investigate the role of tumor budding (TB) in predicting lymph node metastasis of intestinal-type early gastric adenocarcinoma, and to determine the optimal cutoff value of TB number. Methods: A total of 202 patients with intestinal-type early gastric adenocarcinoma, who underwent surgical operation at the Affiliated Wuxi People's Hospital of Nanjing Medical University, Jiangsu, China from 2008 to 2018 were included. According to the International Tumor Budding Consensus Conference (ITBCC) criteria, the number of TB for each case was assessed. The receiver operating characteristic (ROC) curve was employed to determine the optimal cutoff value of TB number for predicting lymph node metastasis, and multivariate logistic regression was used to analyze whether a high TB number was an independent risk factor for lymph node metastasis. In addition, in the patients, who met the indications for endoscopic resection and developed lymph node metastasis, the association of a high number of TB with lymph node metastasis was examined. Results: TBs were observed in 63.4% (128/202) of intestinal-type early gastric adenocarcinomas. Using ROC curve, 4 TBs was found as the optimal cutoff value to predict lymph node metastasis (area under the curve 0.767; sensitivity 0.657; specificity 0.780). Therefore, the 202 cases were divided into two groups: the high-budding (≥4 TBs) group (n=60) and the low-budding (<4 TBs) group (n=142). The high-budding group exhibited a higher rate of lymph node metastasis than that of the low-budding group (41.7% vs 9.1%, P<0.01), and ≥4 TBs was associated with deeper invasion and lymph vessel invasion (P<0.01). The multivariate regression model showed that ≥4 TBs was an independent risk factor for lymph node metastasis (Hazard ratio=8.760, 95%CI 2.648-28.987; P<0.01). Meanwhile, 4 TBs as the cutoff value could better predict lymph node metastasis than the cutoff value advised by the ITBCC. In addition, 3 cases were found to have developed lymph node metastasis even that they met the expanded indications for endoscopic resection, and 2 of these 3 cases exhibited a higher TB number (≥4 TBs). Conclusions: More than 4 TBs are a useful indicator for predicting lymph node metastasis in intestinal-type early gastric adenocarcinoma. It may be used to as an endoscopic resection criterion for patients with a high risk of lymph node metastasis.

Persistence with medical treatment for Wilson disease in China based on a single center's survey research

BACKGROUND

Wilson's disease (WD) is one of the few hereditary diseases that can be successfully treated with medicines. We conduct this survey research to assess treatment persistence among patients with WD and try to identify what factors affect the treatment persistence.

METHODS

We employed WeChat which is the most popular social software in China to carry out this anonymous questionnaire research. The questionnaire included medication adherence scale. We also collected available medical records related to demographic and clinical characteristics. All the patients were divided into group of persistence with drug treatment (PDT) and nonpersistence with drug treatment (n-PDT).

RESULTS

We collected 242 qualified questionnaires. Only 66.5% of patients were PDT during the mean 12.6 years of follow-up. In PDT group, better outcomes were observed: improvement (78.3%) and no change (16.1%) versus those in n-PDT (55.6%; and 28.4%, respectively). In PDT group, only nine patients deteriorated (6.8%) in comparison with 13 patients in n-PDT (16.0%). The adverse events (AEs) in PDT group were significantly less than those in n-PDT group. There were no significant differences in clinical type, gender, age, education level, and family knowledge about WD between the two groups. There were significant differences in AEs and family position toward treatment.

CONCLUSION

Medication Adherence of Chinese WD patients was low. One third of the patients (33.5%) were unable to PDT, and it had an important negative effect on clinical outcome. AEs and family support had an important impact on treatment persistence.

SHARPIN stabilizes β-catenin through a linear ubiquitination-independent manner to support gastric tumorigenesis

BACKGROUND

Aberrant activation of Wnt/β-catenin signaling by dysregulated post-translational protein modifications, especially ubiquitination is causally linked to cancer development and progression. Although Lys48-linked ubiquitination is known to regulate Wnt/β-catenin signaling, it remains largely obscure how other types of ubiquitination, such as linear ubiquitination governs its signaling activity.

METHODS

The expression and regulatory mechanism of linear ubiquitin chain assembly complex (LUBAC) on Wnt/β-catenin signaling was examined by immunoprecipitation, western blot and immunohistochemical staining. The ubiquitination status of β-catenin was detected by ubiquitination assay. The impacts of SHARPIN, a core component of LUBAC on malignant behaviors of gastric cancer cells were determined by various functional assays in vitro and in vivo.

RESULTS

Unlike a canonical role in promoting linear ubiquitination, SHARPIN specifically interacts with β-catenin to maintain its protein stability. Mechanistically, SHARPIN competes with the E3 ubiquitin ligase β-Trcp1 for β-catenin binding, thereby decreasing β-catenin ubiquitination levels to abolish its proteasomal degradation. Importantly, SHARPIN is required for invasiveness and malignant growth of gastric cancer cells in vitro and in vivo, a function that is largely dependent on its binding partner β-catenin. In line with these findings, elevated expression of SHARPIN in gastric cancer tissues is associated with disease malignancy and correlates with β-catenin expression levels.

CONCLUSIONS

Our findings reveal a novel molecular link connecting linear ubiquitination machinery and Wnt/β-catenin signaling via SHARPIN-mediated stabilization of β-catenin. Targeting the linear ubiquitination-independent function of SHARPIN could be exploited to inhibit the hyperactive β-catenin signaling in a subset of human gastric cancers.

Towards Safe Weakly Supervised Learning

In this paper, we study weakly supervised learning where a large amount of data supervision is not accessible. This includes i) incomplete supervision, where only a small subset of labels is given, such as semi-supervised learning and domain adaptation; ii) inexact supervision, where only coarse-grained labels are given, such as multi-instance learning and iii) inaccurate supervision, where the given labels are not always ground-truth, such as label noise learning. Unlike supervised learning which typically achieves performance improvement with more labeled examples, weakly supervised learning may sometimes even degenerate performance with more weakly supervised data. Such deficiency seriously hinders the deployment of weakly supervised learning to real tasks. It is thus highly desired to study safe weakly supervised learning, which never seriously hurts performance. To this end, we present a generic ensemble learning scheme to derive a safe prediction by integrating multiple weakly supervised learners. We optimize the worst-case performance gain and lead to a maximin optimization. This brings multiple advantages to safe weakly supervised learning. First, for many commonly used convex loss functions in classification and regression, it is guaranteed to derive a safe prediction under a mild condition. Second, prior knowledge related to the weight of the base weakly supervised learners can be flexibly embedded. Third, it can be globally and efficiently addressed by simple convex quadratic or linear program. Finally, it is in an intuitive geometric interpretation with the least square loss. Extensive experiments on various weakly supervised learning tasks, including semi-supervised learning, domain adaptation, multi-instance learning and label noise learning demonstrate our effectiveness.

[Bioinformatics analysis of key genes and prognosis-related genes during the onset of hepatocellular carcinoma]

Objective: To screen and analyze the differentially-expressed genes (DEGs) in primary hepatocellular carcinoma tissues and adjacent tissues using bioinformatics methods to explore the molecular mechanism of the occurrence and prognosis of primary hepatocellular carcinoma. Methods: GSE76427 data set was collected through GEO database, and DEGs were identified using GEO2R online analysis. Go and KEGG databases were used for enrichment and functional annotation of DEGs. Protein interaction network was built based on the STRING database and Cytoscape software to analyze the key genes of hepatocellular carcinoma, and the survival curve of these key genes were analyzed using the GEPIA database. Results: A total of 74 hepatocellular carcinoma DEGs were screened, of which 3 and 71 were up-and-down-regulated genes. The results of GO enrichment analysis showed that the down-regulated DEGs were mainly involved in cell response to cadmium and zinc ions, negative growth regulation, heterologous metabolic processes and hormone-mediated signaling pathways. KEGG pathway enrichment analysis results showed that the down-regulated DEGs pathway were mainly involved in retinol metabolism, chemical carcinogenesis, drug metabolism-cytochrome P450, cytochrome P450 metabolizing xenobiotics, tryptophan metabolism and caffeine metabolism. Protein interaction network had screened out 10 down-regulated core genes: MT1G, MT1F, MT1X, MT1E, MT1H, insulin-like growth factor 1, FOS, CXCL12, EGR1, and BGN. Among them, the insulin-like growth factor 1 was related to the prognosis of primary hepatocellular carcinoma. Conclusion: Bioinformatics analysis results of HCC chip data showed that 10 key genes may play a key role in the occurrence and development of HCC and the insulin like growth factor 1 is associated with the prognosis of primary hepatocellular carcinoma.

The split-off terahertz radiating dipoles on thermally reduced α-V2O5 (001) surface

The trapped electron states on a pliable lattice have different localization and physical chemistry characteristics. Here, terahertz time-domain measurements suggest that the formation of vanadyl oxygen defect, in the presence of the surface potential traps and mobile charge carriers, leads to a transient charge distribution that forms terahertz radiating dipoles in V2O5. The emergence of radiating dipoles is evidenced by terahertz responses with a two-valley feature of the thermally reduced α-V2O5 (001) thin films in the temperature range of 300-700 K. The two photoconductance valleys on a several millielectron volts interval are related to two emergent split-off traps, which originate from the VO6 octahedra distortion upon the vanadyl oxygen desorption on the surface. The pliable surface lattices plays a decisive role. So long as the α-V2O5 (001) thin films are covered by a 30 nm-thick Al2O3 capping layer, the distinct two-valley feature disappears completely in the full temperature range. The terahertz radiating dipoles with a fine energy structure is potentially a new measure for charge dynamics on the α-V2O5 (001) surface.

Ionic Liquid-Modified Porous Organometallic Polymers as Efficient and Selective Photocatalysts for Visible-Light-Driven CO2 Reduction

In the photoreduction of CO₂ to CO, the competitive H₂ evolution is always inevitable due to the approximate reduction potentials of H⁺/H₂ and CO₂/CO, which results in poor selectivity for CO production. Herein, imidazolium-type ionic liquid- (IL-) modified rhenium bipyridine-based porous organometallic polymers (Re-POMP-IL) were designed as efficient and selective photocatalysts for visible-light CO₂ photoreduction to CO based on the affinity of IL with CO₂. Photoreduction studies demonstrated that CO₂ photoreduction promoted by Re-POMP-IL functioning as the catalyst exhibits excellent CO selectivity up to 95.5% and generate 40.1 mmol CO/g of Re-POMP-IL1.0 (obtained by providing equivalent [(5,5′-divinyl-2,2′-bipyridine)Re(CO)₃Cl] and 3-ethyl-1-vinyl-1H-imidazol-3-ium bromide) at 12 h, outperforming that attained with the corresponding Re-POMP analogue without IL, which highlights the crucial role of IL. Notably, CO₂ adsorption, light harvesting, and transfer of photogenerated charges as key steps for CO₂RR were studied by employing POMPs modified with different amounts of IL as photocatalysts, among which the CO₂ affinity as an important factor for POMPs catalyzed CO₂ reduction is revealed. Overall, this work provides a practical pathway to improve the CO₂ photoreduction efficiency and CO selectivity by employing IL as a regulator.

[Gastric adenocarcinoma with enteroblastic differentiation and elevated serum alpha fetoprotein]

Objective: To study the proportion and clinicopathological characteristics of gastric adenocarcinoma with enteroblastic differentiation (GAED) in gastric cancers showing an elevated serum alpha fetoprotein(AFP). Methods: A total of 724 resected gastric adenocarcinomas were collected from 2008 to 2018 at the 904 Hospital of Joint Service Support Force, and cases with pre-operative serum AFP>10 μg/L were screened. From the cases with elevated serum AFP, GAED cases were further evaluated based on morphology. Then the clincopathological features and immunohistochemical phenotypes of GAED were reviewed. In addition, the amplification of HER2 gene was detected with fluorescence in situ hybridization(FISH). When overall survival (OS) and progression-free survival (PFS) of GAED were analyzed, 289 cases ordinary gastric adenocarcinoma with normal serum AFP were employed as a control. Results: The percentage of GAED was 44% (11/25) in gastric cancers with elevated serum AFP. GAED was histologically tubular or papillary with clear cytoplasm, and some GAED cases showed cystadenoid structure similar to embryo sac (5 cases), homogeneous eosinophilic granules (4 cases) and intragland ulareosinophilic material (6 cases). All 11 GAED cases had lymph node metastasis. Liver metastasis and vascular thrombus were observed in 2 cases and 5 cases respectively. GAED was immunohistochemically positive for CDX2 (11/11), CD10 (8/11) and MUC2(3/11), which were intestinal epithelium differentiation markers. Meanwhile, primitive markers SALL4 (8/11), GPC3 (7/11) and AFP (5/11) were also expressed in GAED, and HER2 gene amplification was found in 3 cases (3/11) of GAED. Lastly, the PFS of GAED were significantly shorter than that of the control group (P=0.02), while OS was not statistically different between these two groups (P=0.99). Conclusions: Patients with GAED usually have a higher rate of elevated serum AFP in gastric adenocarcinoma, and the cancer exhibites features of both intestinal and primitive differentiation. As GAED is highly invasive, the prognosis of GAED may be poor. For GAED, the diagnosis of well-differentiated or moderately-differentiated adenocarcinoma should be avoided, because this diagnosis leads to underestimated malignant potential.

Learning With Interpretable Structure From Gated RNN

The interpretability of deep learning models has raised extended attention these years. It will be beneficial if we can learn an interpretable structure from deep learning models. In this article, we focus on recurrent neural networks (RNNs), especially gated RNNs whose inner mechanism is still not clearly understood. We find that finite-state automaton (FSA) that processes sequential data have a more interpretable inner mechanism according to the definition of interpretability and can be learned from RNNs as the interpretable structure. We propose two methods to learn FSA from RNN based on two different clustering methods. With the learned FSA and via experiments on artificial and real data sets, we find that FSA is more trustable than the RNN from which it learned, which gives FSA a chance to substitute RNNs in applications involving humans' lives or dangerous facilities. Besides, we analyze how the number of gates affects the performance of RNN. Our result suggests that gate in RNN is important but the less the better, which could be a guidance to design other RNNs. Finally, we observe that the FSA learned from RNN gives semantic aggregated states, and its transition graph shows us a very interesting vision of how RNNs intrinsically handle text classification tasks.

[Integrated analysis of DNA methylation and gene expression profiles of hepatocellular carcinoma to construct miR-1180-3p relevant ceRNA regulatory network]

Objective: This study analyzes the expression level of miR-1180-3p and constructs the regulatory network of relevant ceRNA by integrating the DNA methylation and gene expression profile of hepatocellular carcinoma from the Cancer Genome Atlas (TCGA). Methods: Firstly, the expression level of miR-1180-3p in hepatocellular carcinoma and adjacent tissues was analyzed by TCGA database, and the differential expression of lncrna and mRNA was screened. Secondly, the LncBase database and the TargetScan database were used to predict the relationship between miR-1180-3p and lncRNA and mRNA, and the DNA methylation-mediated lncRNA was screened by the DNA methylation profile of lncRNA. Finally, Cytoscape software was used to construct miR-1180-3p relevant ceRNA network, and WebGestalt website was used to perform GO and KEGG analysis of related mRNA in ceRNA. Results: Compared with patients with low expression of miR-1180-3p (mean overall survival duration, 5.69 ± 0.35 years), patients with high expression of miR-1180-3p had shorter overall survival time (mean overall survival duration, 3.99 ± 0.47 years), indicating that the high expression of miR-1180-3p was hepatocellular carcinoma risk factor affecting the prognosis (HR = 1.28, 95% CI = 1.1 ~ 1.5, P < 0.01). A miR-1180-3p related ceRNA regulatory network was constructed in this study, which contained 2 lncRNAs (F11-AS1 and LINC01511) and 37 mRNAs. Conclusion: This study has successfully constructed miR-1180-3p relevant ceRNA regulatory network, and DNA methylation-mediated F11-AS1 and F11-AS1/miR-1180-3p/C11of54 ceRNA regulatory axis has played an important role in the occurrence and development of hepatocellular carcinoma.

Giant "heart appearance-like sign" on MRI in bilateral ponto-medullary junction infraction: case report

Background

Bilateral medial medullary infarction (MMI) is uncommon and bilateral medial pons infarction (MPI) is even rarer. “Heart appearance” on magnetic resonance imaging (MRI) is a characteristic presentation of bilateral medial medullary infarction (MMI).

Case presentation

We present 67-year-old Chinese diabetic and hypertensive female patient affected with “heart appearance-like” infarction in bilateral ponto-medullary junction on MRI. Abnormal signal was observed in the bilateral ponto-medullary junction on T1, T2, fluid-attenuated inversion recovery and apparent diffusion coefficient (ADC). The whole brain digital subtraction angiography (DSA) showed the basilar artery and vertebral artery remained intact. Therefore, we speculated that the bilateral ponto-medullary junction infarction might be caused by the deep perforating branch of the basilar artery.

Conclusions

As far as we know, the “heart appearance-like” infraction in bilateral ponto-medullary junction was not reported. Our case also suggests that bilateral ischemic infraction involvement of the medulla and pon is possible even in the context of an intact basilar artery.

Synthesis of Polyurethane Hydrogel and Polyurethane Thermoplastic Elastomer Composite Based Separation Membranes

A series of polyurethane hydrogel and polyurethane thermoplastic elastomer composite based separation membranes were successfully prepared via wet phase inversion method. The morphology, chemical structure, phase transition temperature and crystallinity of the polyurethane (PU) membranes were characterized by SEM, FTIR, DSC, and XRD, respectively. The SEM observation showed that the PU membranes exhibited irregular porous structure on the surface and path of the hole was flexural and asymmetrical in cross-section. The FTIR analysis demonstrated that thermalsensitive groups and pH-sensitive components (-N(CH₃)-) were incorporated into the PU network. The DSC experiment and XRD experiment showed that the regular arrangement of PU network was destroyed partly due to the introduction of polyurethane thermoplastic elastomer. The equilibrium swelling ratio (ESR) and water flux (J) for PU membranes clearly decreased and increased with functional groups and sophisticated structure of PU membranes, respectively. In addition, the permeation experiments indicated that the permeation percentage (P) of the glycine was strongly affected by the external temperature and pH value.

Attenuation of a virulent swine acute diarrhea syndrome coronavirus strain via cell culture passage

Swine acute diarrhea syndrome coronavirus (SADS-CoV) is a newly identified enteric alphacoronavirus that causes fatal diarrhea in newborn piglets in China. Here, we propagated a virulent strain SADS-CoV/CN/GDWT/2017 in Vero cells for up to 83 passages. Four strains of SADS-CoV/GDWT-P7, -P18, -P48 and -P83 were isolated and characterized. Sequence alignments showed that these four novel strains exhibited 16 nucleotide mutations and resultant 10 amino acid substitutions in open reading frame 1a/1b, spike, NS3a, envelope, membrane and nucleocapsid proteins. Furthermore, a 58-bp deletion in NS7a/7b was found in P48 and P83 strains, which led to the loss of NS7b and 38 amino acid changes of NS7a. Pig infection studies showed that the P7 strain caused typical watery diarrhea, while the P83 strain induced none-to-mild, delayed and transient diarrhea. This is the first report on cell adaption of a virulent SADS-CoV strain, which gives information on the potential virulence determinants of SADS-CoV.

Distributed Deep Forest and its Application to Automatic Detection of Cash-Out Fraud

Internet companies are facing the need for handling large-scale machine learning applications on a daily basis and distributed implementation of machine learning algorithms which can handle extra-large-scale tasks with great performance is widely needed. Deep forest is a recently proposed deep learning framework which uses tree ensembles as its building blocks and it has achieved highly competitive results on various domains of tasks. However, it has not been tested on extremely large-scale tasks. In this work, based on our parameter server system, we developed the distributed version of deep forest. To meet the need for real-world tasks, many improvements are introduced to the original deep forest model, including MART (Multiple Additive Regression Tree) as base learners for efficiency and effectiveness consideration, the cost-based method for handling prevalent class-imbalanced data, MART based feature selection for high dimension data, and different evaluation metrics for automatically determining the cascade level. We tested the deep forest model on an extra-large-scale task, i.e., automatic detection of cash-out fraud, with more than 100 million training samples. Experimental results showed that the deep forest model has the best performance according to the evaluation metrics from different perspectives even with very little effort for parameter tuning. This model can block fraud transactions in a large amount of money each day. Even compared with the best-deployed model, the deep forest model can additionally bring a significant decrease in economic loss each day.

Fast Multi-Instance Multi-Label Learning

In many real-world tasks, particularly those involving data objects with complicated semantics such as images and texts, one object can be represented by multiple instances and simultaneously be associated with multiple labels. Such tasks can be formulated as multi-instance multi-label learning (MIML) problems, and have been extensively studied during the past few years. Existing MIML approaches have been found useful in many applications; however, most of them can only handle moderate-sized data. To efficiently handle large data sets, in this paper we propose the MIMLfast approach, which first constructs a low-dimensional subspace shared by all labels, and then trains label specific linear models to optimize approximated ranking loss via stochastic gradient descent. Although the MIML problem is complicated, MIMLfast is able to achieve excellent performance by exploiting label relations with shared space and discovering sub-concepts for complicated labels. Experiments show that the performance of MIMLfast is highly competitive to state-of-the-art techniques, whereas its time cost is much less. Moreover, our approach is able to identify the most representative instance for each label, and thus providing a chance to understand the relation between input patterns and output label semantics.

Efficient Training for Positive Unlabeled Learning

Positive unlabeled (PU) learning is useful in various practical situations, where there is a need to learn a classifier for a class of interest from an unlabeled data set, which may contain anomalies as well as samples from unknown classes. The learning task can be formulated as an optimization problem under the framework of statistical learning theory. Recent studies have theoretically analyzed its properties and generalization performance, nevertheless, little effort has been made to consider the problem of scalability, especially when large sets of unlabeled data are available. In this work we propose a novel scalable PU learning algorithm that is theoretically proven to provide the optimal solution, while showing superior computational and memory performance. Experimental evaluation confirms the theoretical evidence and shows that the proposed method can be successfully applied to a large variety of real-world problems involving PU learning.

[Bortezomib-based induction chemotherapy followed by autologous hematopoietic stem cell transplantation and maintenance in 200 patients with multiple myeloma: long-term follow-up results from single center]

Objective: To study the efficacy, safety and long-term outcomes of integrated strategy of bortezomib-based induction regimens followed by autologous hematopoietic stem cell (ASCT) and maintenance therapy in Chinese multiple myeloma (MM) patients. Methods: 200 MM patients receiving integrated strategy of bortezomib--based induction regimens followed by ASCT and maintenance therapy were retrospectively and prospectively analyzed from December 1. 2006 to April 30. 2018. Results: The complete remission rates (CR) and better than very good partial remission rates (VGPR) after induction therapy, transplantation and maintenance therapy were respectively 31% and 75.5%, 51.8% and 87.7%,73.6% and 93.4%. There was no difference between 4 cycles and more than 5 cycles induction chemotherapy. The negative rate of MRD detection by flow cytometry was 17.6% and 38.2% respectively after induction and 3 months after transplantation. The negative rate of MRD gradually increased during the maintenance therapy. The success rate of high dose CTX combined with G-CSF mobilization was 95.5% and transplantation related mortality (TRM) was zero. The median time to progress (TTP) was 75.3 months and the median overall survival (OS) was 99.5 months. TTP of patients obtaining CR and negative MRD after induction were longer that those of no CR and positive MRD. TTP and OS of patients receiving triple-drug induction and ASCT in early stage were longer than those of double-drug induction and ASCT in late stage. LDH≥240 U/L, high risk cytogenetics, ISS II+III stage and HBsAg positive were prognostic factors at diagnosis. However, only MRD and high risk cytogenetics were independent prognostic factors after transplantation and maintenance therapy. The clinical characteristics of patients of TTP ≥6 years were listed below: light-chain type M protein, ISS I stage, normal level of hemoglobin and platelet, normal LDH, HBsAg negative, chromosome 17p-negative, good response and sustained good response. Conclusions: Integrated strategy of bortezomib-based induction regimens followed by ASCT and maintenance therapy can significantly improve the short-term and long-term efficacy. The prognostic factors of TTP in different disease stages were different. Response to treatment, especially MRD, played a more important role in prognostic factors.

BRD4 Promotes Gastric Cancer Progression and Metastasis through Acetylation-Dependent Stabilization of Snail

Cancer metastasis, a leading cause of death in patients, is associated with aberrant expression of epigenetic modifiers, yet it remains poorly defined how epigenetic readers drive metastatic growth and whether epigenetic readers are targetable to control metastasis. Here, we report that bromodomain-containing protein 4 (BRD4), a histone acetylation reader and emerging anticancer therapeutic target, promotes progression and metastasis of gastric cancer. The abundance of BRD4 in human gastric cancer tissues correlated with shortened metastasis-free gastric cancer patient survival. Consistently, BRD4 maintained invasiveness of cancer cells in vitro and their dissemination at distal organs in vivo. Surprisingly, BRD4 function in this context was independent of its putative transcriptional targets such as MYC or BCL2, but rather through stabilization of Snail at posttranslational levels. In an acetylation-dependent manner, BRD4 recognized acetylated lysine 146 (K146) and K187 on Snail to prevent Snail recognition by its E3 ubiquitin ligases FBXL14 and β-Trcp1, thereby inhibiting Snail polyubiquitination and proteasomal degradation. Accordingly, genome-wide transcriptome analyses identified that BRD4 and Snail regulate a partially shared metastatic gene signature in gastric cancer cells. These findings reveal a noncanonical posttranscriptional regulatory function of BRD4 in maintaining cancer growth and dissemination, with immediate translational implications for treating gastric metastatic malignancies with clinically available bromodomain inhibitors. SIGNIFICANCE: These findings reveal a novel posttranscriptional regulatory function of the epigenetic reader BRD4 in cancer metastasis via stabilizing Snail, with immediate translational implication for treating metastatic malignancies with clinically available bromodomain inhibitors. GRAPHICAL ABSTRACT: http://cancerres.aacrjournals.org/content/canres/79/19/4869/F1.large.jpg.

Characteristics of neurological Wilson's disease with corpus callosum abnormalities

BACKGROUND

Wilson's disease (WD) is an autosomal recessive disease of impaired copper metabolism. Previous study demonstrated that WD with corpus callosum abnormalities (WD-CCA) was limited to the posterior part (splenium). This study aimed to compare clinical features between WD-CCA and WD without corpus callosum abnormalities (WD-no-CCA).

METHODS

Forty-one WD patients who had markedly neurological dysfunctions were included in this study. We retrospectively reviewed clinical, biochemical characteristics and MRI findings in the 41 WD patients. All patients were assessed using the Unified Wilson's Disease Rating Scale.

RESULTS

Nine patients had corpus callosum abnormalities, 4 of 9 patients had abnormal signal in the genu and splenium, 5 of 9 patients had abnormal signal only in the splenium. WD-CCA had longer course (9.9 ± 4.0 years vs. 3.4 ± 3.6 years, p<0.01), more severe neurological dysfunctions (37.6 vs. 65.9, p<0.01) and higher psychiatric symptoms scores (11.2 vs. 22.5, p<0.01) than WD-no-CCA. The MRI findings indicated that WD-CCA had higher ratio than WD-no-CCA in globus pallidus (88.9% vs. 43.8%, p = 0.024) and thalamus (100% vs. 59.4%, p = 0.038). The index of liver function and copper metabolism had no significant in WD-CCA and WD-no-CCA patients.

CONCLUSION

Our findings indicate Wilson's disease can involve the posterior as well as the anterior part of CC and patients with CC involvement had more extensive brain lesions, more severe neurological dysfunctions and psychiatric symptoms.