A continuous learning approach to brain tumor segmentation: integrating multi-scale spatial distillation and pseudo-labeling strategies.

Introduction: This study presents a novel continuous learning framework tailored for brain tumour segmentation, addressing a critical step in both diagnosis and treatment planning. This framework addresses common challenges in brain tumour segmentation, such as computational complexity, limited generalisability, and the extensive need for manual annotation. Methods: Our approach uniquely combines multi-scale spatial distillation with pseudo-labelling strategies, exploiting the coordinated capabilities of the ResNet18 and DeepLabV3+ network architectures. This integration enhances feature extraction and efficiently manages model size, promoting accurate and fast segmentation. To mitigate the problem of catastrophic forgetting during model training, our methodology incorporates a multi-scale spatial distillation scheme. This scheme is essential for maintaining model diversity and preserving knowledge from previous training phases. In addition, a confidence-based pseudo-labelling technique is employed, allowing the model to self-improve based on its predictions and ensuring a balanced treatment of data categories. Results: The effectiveness of our framework has been evaluated on three publicly available datasets (BraTS2019, BraTS2020, BraTS2021) and one proprietary dataset (BraTS_FAHZU) using performance metrics such as Dice coefficient, sensitivity, specificity and Hausdorff95 distance. The results consistently show competitive performance against other state-of-the-art segmentation techniques, demonstrating improved accuracy and efficiency. Discussion: This advance has significant implications for the field of medical image segmentation. Our code is freely available at https://github.com/smallboy-code/A-brain-tumor-segmentation-frameworkusing-continual-learning.

A Cross-Correlated Delay Shift Supervised Learning Method for Spiking Neurons with Application to Interictal Spike Detection in Epilepsy.

This study introduces a novel learning algorithm for spiking neurons, called CCDS, which is able to learn and reproduce arbitrary spike patterns in a supervised fashion allowing the processing of spatiotemporal information encoded in the precise timing of spikes. Unlike the Remote Supervised Method (ReSuMe), synapse delays and axonal delays in CCDS are variants which are modulated together with weights during learning. The CCDS rule is both biologically plausible and computationally efficient. The properties of this learning rule are investigated extensively through experimental evaluations in terms of reliability, adaptive learning performance, generality to different neuron models, learning in the presence of noise, effects of its learning parameters and classification performance. Results presented show that the CCDS learning method achieves learning accuracy and learning speed comparable with ReSuMe, but improves classification accuracy when compared to both the Spike Pattern Association Neuron (SPAN) learning rule and the Tempotron learning rule. The merit of CCDS rule is further validated on a practical example involving the automated detection of interictal spikes in EEG records of patients with epilepsy. Results again show that with proper encoding, the CCDS rule achieves good recognition performance.

[The impact of early surgery on long-term outcome of patients with left-sided infective endocarditis].

OBJECTIVE: This study aims to evaluate the impact of early surgery on long-term outcome of patients with left-sided native valve infective endocarditis (IE). METHODS: Clinical data were retrospectively reviewed in 239 consecutive patients with left-sided native valve IE from 2002 to 2012 in Peking Union Medical College Hospital (PUMCH). Propensity score was used to match patients in the early operation and conventional treatment groups. RESULTS: Early surgery was performed in 70 (29.3%) patients and the conventional treatment strategy was applied in 169 (70.7%) patients. The median follow-up period was 2 years. IE-related mortality was lower in the early operation group than in the conventional treatment group (10.0% vs 23.1%, P = 0.02). For 58 propensity score-matched pairs, the cumulative survival free from IE related death was significantly higher in the early operation group than in the conventional treatment group (P = 0.027). Regression analysis of the matched cohorts revealed that early surgery was independently associated with decreased IE-related mortality (HR 0.286; 95%CI 0.092-0.893; P = 0.031). While either cardiac function with NYHA Class III-IV (HR 4.044; 95%CI 1.318-12.407; P = 0.015) or uncontrolled infection (HR 52.064; 95%CI 10.996-247.194; P < 0.001) was associated with poor prognosis of increased mortality. CONCLUSIONS: Early surgery improved long-term outcome in patients with left-sided native valve IE compared with conventional therapy. Risk factors related to increased mortality included heart failure and uncontrollable infection.

A generalized Leaky Integrate-and-Fire neuron model with fast implementation method.

This study introduces a new Generalized Leaky Integrate-and-Fire (GLIF) neuron model with variable leaking resistor and bias current in order to reproduce accurately the membrane voltage dynamics of a biological neuron. The accuracy of this model is ensured by adjusting its parameters to the statistical properties of the Hodgkin-Huxley model outputs; while the speed is enhanced by introducing a Generalized Exponential Moving Average method that converts the parameterized kernel functions into pre-calculated lookup tables based on an analytic solution of the dynamic equations of the GLIF model.

A biological plausible Generalized Leaky Integrate-and-Fire neuron model.

This study introduces a new Generalized Leaky Integrate-and-Fire (GLIF) neuron model. Unlike Normal Leaky Integrate-and-Fire (NLIF) models, the leaking resistor in the GLIF model equation is assumed to be variable, and an additional term would have the bias current added to the model equation in order to improve the accuracy. Adjusting the parameters defined for the leaking resistor and bias current, a GLIF model could be accurately matched to any Hodgkin-Huxley (HH) model and be able to reproduce plausible biological neuron behaviors.

[Cardiac involvement of the type I mucopolysaccharidosis].

OBJECTIVE: To investigate the manifestations of cardiac involvement in the patients with mucopolysaccharidosis I (MPS I). METHODS: The clinical data of 10 MPS I patients were collected. Electrocardiography (ECG) and echocardiography (Echo) were performed in all patients and then analyzed. RESULTS: Among the ten patients, seven were men. The onset age of MPS was (0.5 ~ 8.0) years old and the age of diagnosis was (1.8 ~ 20.0) years old. Two patients had grade 2 precordial systolic murmur. ECG was abnormal in three patients with right ventricular hypertrophy in two and right axis deviation in another one. Echo showed valvular thickening and insufficiency in nine patients, enlarged left atrium and ventricle in one patient, pulmonary hypertension and right ventricular hypertrophy in two patients and abnormal left ventricular configuration in five patients. CONCLUSIONS: Cardiac involvement is common in MPS I patients and may present as valvular thickening with regurgitation, abnormal left ventricular configuration and pulmonary hypertension. The cardiac involvement progresses with age. ECG and Echo should be done regularly during follow-up of MPS I patients.

Effect of high-dose statin versus low-dose statin plus ezetimibe on endothelial function: a meta-analysis of randomized trials.

BACKGROUND: Combining low-dose statin and ezetimibe reduces the low-density lipoprotein cholesterol (LDL-C) similar to high-dose statin. However, whether there is a difference in the effect of these 2 lipid-lowering regimes on endothelial function is still controversial. METHODS: We performed a systematic search of databases (MEDLINE [1950 to September 2011], EMBASE [1966 to September 2011]) and references of identified studies. Completely published randomized controlled trials comparing the effect of high-dose statin with low-dose stain plus ezetimibe on endothelial function (flow-mediated dilation [FMD] method) were included in this study. RESULTS: Six trials with a total of 213 participants were included in the meta-analysis. The pooled weighted mean difference of FMD did not differ between the 2 lipid-lowering regimes (0.22%; 95% confidence interval [CI]: -0.85%-1.29%, P = .68). Furthermore, no significant reduction in LDL-C and C-reactive protein (CRP) occurred with high-dose statin versus low-dose statin plus ezetimibe (pooled weighted mean differences of LDL-C and CRP were -4.12 mg/dL, 95% CI: -9.54-1.12 mg/dL, P = .12, and -0.02 mg/L, 95% CI: -0.31-0.27 mg/L, P = .89, respectively). CONCLUSIONS: Based on the currently available evidence, combining a low-dose statin with ezetimibe may provide similar beneficial effects on endothelial function as high-dose statin.

[Association of interleukin 28B polymorphisms with response to pegylatedinterferon plus ribavirin therapy for chronic hepatitis C].

OBJECTIVE: To investigate the characteristics of gene polymorphisms at rs12979860 of interleukin 28B (IL28B) and explore the relationships between the genetic polymorphisms and the antiviral therapy efficiency for chronic hepatitis C patients in the Sichuan region of China. METHODS: Data from 56 patients treated for 48 weeks with PEG-IFN alpha-2a plus weight-based Ribavirin (RBV), which were followed for 24 weeks after the end of treatment, were analyzed. And the IL28B rs12979860 genotype was detected by polymerase chain reaction-restriction techniques (PCR) and sequencing analysis. RESULTS: Two genotypes, CC (76.8%) and CT (23.2%), were identified in the study. There are no significant correlation in sex, age, body weight, routes of infection, baseline ALT value, baseline viral load and hepatitis C viral (HCV) genotype between the patients with CC genotype and CT genotype (P>0.05). PEG-IFN alpha-2a plus RBV showed a conspicuous therapeutic effect in patients of the Sichuan region of China, and the rate of sustained virological response (SVR) was 82.1% (46/56). The higher rates of SVR were observed in patients with IL28B genotype CC than genotype CT (90.7% versus 53.8%, P=0.009). Statistically higher proportion of SVR wasn't observed in patients with lower baseline viral load (< or =6 x 10(5) IU/mL) [88.2% versus 79.5% in patients with higher baseline viral load (> or = 6 x 10(5) IU/mL), P=0.684] and statistically lower proportion of SVR wasn't observed in patients infected with HCV genotype 1 (76.9% versus 92.9% in patients infected with HCV genotype non-1, P = 0.363). The higher rates of SVR were observed in patients with IL28B genotype CC than patients with genotype CT in the group of higher baseline viral load (> or = 6 x 10(5) IU/mL) (87.5% versus 42.9%, P=0.033) and in HCV genotype 1 infected patients (89.7% versus 50.0%, P=0.025). CONCLUSION: CC genotype was accounted for the majority at rs12979860 in patients of the Sichuan region of China. The higher rates of SVR were observed in IL28B genotype CC than genotype CT. Compared to HCV viral genotype and baseline viral load, IL28B genotype may predict the treatment effect of greater value.

[Cardiovascular risk profile of patients with glycogen storage disease type I].

OBJECTIVE: To investigate the cardiovascular risk profile in patients with glycogen storage disease (GSD) type I. METHOD: The clinical information of 62 patients with GSD type I who admitted to Peking Union Medical Hospital were reviewed and the cardiovascular risk profile was analyzed. RESULTS: The age of the patient cohort was (8.4 ± 6.9) years and the ratio of male vs. female was 36:26. The median disease duration was (6.7 ± 6.2) years and treatment duration was (38.3 ± 35.2) months. The rate of abnormal change in electrocardiogram and echocardiography was 17.7% and 24.2%, respectively. The serum concentration of total cholesterol (TC), triglyceride (TG), low-density lipoprotein cholesterol (LDL-C), high density lipoprotein cholesterol (HDL-C) and uric acid in patient before and after treatment were (6.18 ± 2.47) mmol/L vs. (5.61 ± 1.84) mmol/L (P = 0.020), (11.17 ± 9.85) mmol/L vs. (6.81 ± 5.97) mmol/L (P = 0.010), (2.55 ± 1.27) mmol/L vs. (2.78 ± 1.07) mmol/L (P = 0.617), (0.98 ± 0.37) mmol/L vs. (0.96 ± 0.23) mmol/L (P = 0.005), (526.53 ± 127.09) µmol/L vs. (490.78 ± 129.79) µmol/L (P = 0.977), respectively. The high-sensitivity C-reactive protein levels tended to be higher after therapy compared before treatment (2.33 ± 3.30) mg/L vs. (3.35 ± 3.39) mg/L, P = 0.431. CONCLUSION: Patients with GSD I are associated with an increased risk for cardiovascular disease.

Echocardiographic characteristics of intravenous leiomyomatosis with intracardiac extension: a single-institution experience.

BACKGROUND: Intravenous leiomyomatosis (IVL) is a rare smooth-muscle proliferation arising from a uterine myoma and occasionally extending into cardiac chambers. METHODS AND RESULTS: A series of 10 consecutive patients with histologically and surgically proven intracardiac IVL between 2000 and 2010 in our hospital were reviewed. The echocardiographic features of 10 cases with IVL and extensive spread into the right-sided cardiac chambers were described for the first time. All patients were female and the mean age was 42±7 years old. The first symptoms of six patients (60%) were exertional dyspnea and palpitation of cardiac origin. Echocardiography showed that all the tumors originated from the inferior vena cava (IVC) and located in cardiac right chambers (70% in right atrium alone, 30% in right ventricle and atrium). Eight masses (80%) were oval, whereas the others (20%) were serpentine, all with well-demarcated borders and most (70%) with heteroechogenic texture. Five tumors (50%) intermittently prolapsed into right ventricle through the tricuspid valve. Two patients with nodules adhering to the top of the tumors had pulmonary tumorous thromboembolism. CONCLUSION: Echocardiography is a simple and important technique to diagnose IVL with intracardiac extension. This disease should be considered in a female patient presenting with an extensive mass from IVC with well-demarcated border in the right-sided cardiac chambers.

A retrospective study of congenital scoliosis and associated cardiac and intraspinal abnormities in a Chinese population.

Our objective is to assess the incidence of cardiac and intraspinal abnormities in Chinese congenital scoliosis (CS) patients and to study the relationship between the associated abnormities and the different CS types. Five-hundred and thirty-nine consecutive Chinese patients with CS were retrospectively studied, and the records of echocardiography, plain radiograph of the entire spine, magnetic resonance imaging of the entire spine and/or myelogram were reviewed. The results indicated that the incidence of cardiac and intraspinal abnormities in CS patients was 14.1 and 24.5%, respectively. There was no difference in the incidence of associated cardiac and intraspinal abnormities in different CS types (P > 0.05). The most common cardiac abnormities in CS patients was mitral valve prolapse, which was followed by congenital heart diseases, including atrial septal defect, ventricular septal defect, bicuspid aortic valve and patent ductus ateriosus. The cardiac abnormities were not likely to be concurrent with intraspinal abnormities in CS patients (P = 0.04). The intraspinal abnormities were more common in female and older patients (all P < 0.05). One or more abnormities mentioned above could be found in 36.8% CS patients and were more likely to be found in female patients (P < 0.01). We concluded that CS is not a simple abnormity, due to the high incidence of associated deformities of other organs, comprehensive assessment was strongly recommended before the surgical correction for CS patients.

Anesthetic considerations of an emergency decompressive craniotomy complicated with Ebstein's anomaly and atrial septal defect.

Despite considerable published papers regarding Ebstein's anomaly (EA) patients receiving open-heart tricuspid valve replacement, non-cardiac emergency surgeries were rarely reported. We report a case of emergency decompressive craniotomy in a patient with EA. Anesthesiologists should pay special attention to the complications and anesthetic management during the non-cardiac surgeries performed in EA patients.

[Cardiovascular manifestations in Chinese patients with hypereosinophilic syndrome].

OBJECTIVE: To evaluate the cardiovascular involvements in Chinese patients with hypereosinophilic syndrome. METHOD: We respectively reviewed 149 inpatients with hypereosinophilic syndrome admitted to Peking Union Medical College Hospital and analyzed the cardiovascular involvements in these patients. RESULTS: Cardiac abnormalities was evidenced in 32.9% patients (49/149). The ratio of male vs female was 34:15. The average age of the patients was (41.3 ± 16.9) years and course of disease was (26.4 ± 72.3) months. Cardiovascular involvements included ST segment and/or T wave (ST-T) ischemic changes, arrhythmia, myocardial injury, cardiac thrombosis, pericardial effusion, pulmonary hypertension, valve disorder, vein or artery thrombosis. After glucocorticoid and/or chemotherapeutic agents and treatment for symptoms, 11 (22.4%) patients achieved remission but have recurrent attacks and 3 (6.1%) patients died from failure in treatment. The prognosis in patients with echocardiogram abnormalities were poorer than those only with electrocardiogram abnormalities (P < 0.05). CONCLUSIONS: Cardiovascular involvements are common in patients with hypereosinophilic syndrome and the manifestation of these involvement is various. Cardiovascular complications of HES are a major source of morbidity and mortality in these disorders.

Magnesium transporter AtMGT9 is essential for pollen development in Arabidopsis.

Magnesium (Mg(2+)) is abundant in plant cells and plays a critical role in many physiological processes. A 10-member gene family AtMGT (also known as AtMRS2) was identified in Arabidopsis, which belongs to a eukaryote subset of the CorA superfamily, functioning as Mg(2+) transporters. Some family members (AtMGT1 and AtMGT10) function as high-affinity Mg(2+) transporter and could complement bacterial mutant or yeast mutant lacking Mg(2+) transport capability. Here we report an AtMGT family member, AtMGT9, that functions as a low-affinity Mg(2+) transporter, and is essential for pollen development. The functional complementation assay in Salmonella mutant strain MM281 showed that AtMGT9 is capable of mediating Mg(2+) uptake in the sub-millimolar range of Mg(2+). The AtMGT9 gene was expressed most strongly in mature anthers and was also detectable in vascular tissues of the leaves, and in young roots. Disruption of AtMGT9 gene expression resulted in abortion of half of the mature pollen grains in heterozygous mutant +/mgt9, and no homozygous mutant plant was obtained in the progeny of selfed +/mgt9 plants. Transgenic plants expressing AtMGT9 in these heterozygous plants can recover the pollen phenotype to the wild type. In addition, AtMGT9 RNAi transgenic plants also showed similar abortive pollen phenotype to mutant +/mgt9. Together, our results demonstrate that AtMGT9 functions as a low-affinity Mg(2+) transporter that plays a crucial role in male gametophyte development and male fertility.

[Clinical and pathological characteristics of constrictive pericarditis in China].

OBJECTIVE: To summarize the clinical and pathological characteristics of constrictive pericarditis in China. METHOD: Data from 150 patients with constrictive pericarditis who admitted to our hospital from 2000 to 2007 were retrospectively analyzed. RESULTS: Constriction pericarditis was detected by echocardiography in 149 out of 150 patients. Pericardial effusion was evidenced in 59.3% patients (89/150). The diagnostic accuracy rate for identifying constrictive pericarditis by echocardiography (98.7%, 107/109) was comparable to that of surgical diagnosis (100%, 109/109). Tuberculosis was the main cause of constrictive pericarditis in this cohort (78.7%, 118/150) including 25 (16.7%) cases with pathological or etiological evidences of tubercular pericarditis, 8 (5.3%) cases with pathologically active tuberculous focus elsewhere in the body, 66 (44.0%) cases with typical clinical tuberculosis manifestation and responded to anti-tubercular therapy and 19 (12.7%) cases with a diagnosis of suspicious tuberculosis. Pericardiectomy was performed in 108 cases and pericardial biopsy and surgical drainage was performed in 1 patient. In hospital death rate was 8.7% (13/150, 4 tubercular patients and 9 non-tubercular). CONCLUSION: Tuberculosis is the leading cause of constrictive pericarditis in this cohort and the best diagnosis tool is echocardiography other than pathological and etiological findings in pericardium.