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Film capacitors are used in power electronic converters due to their higher reliability compared to aluminum electrolytic capacitors. Humidity is one of the critical factors affecting the aging of film capacitors. However, the existing methodologies for the lifetime estimation of film capacitors rarely consider humidity. Besides, sometimes it is hard to obtain a large amount of data in the accelerated aging test of the device. To solve these problems, this article proposes a lifetime estimation methodology that requires fewer data and testing time. In the proposed methodology, humidity dummy variables are introduced into the degradation model based on the multivariate linear regression (MLR) algorithm. The impact of introduced dummy variables with different structures on the degradation model is studied and the effect of the proposed lifetime estimation method is verified. The results show that the proposed scheme achieves a comparable performance and can be valid in reality.

Background A reliable and effective method is required to deliver agent that can aid the in vivo imaging of retinal vessels. The aim of the present study was to evaluate retro-orbital (RO) injection of fluorescein-labeled isothiocyanate dextran (FITC-dextran) as a method of demonstrating retinal neovascularization (NV) and avascular areas in oxygen-induced retinopathy (OIR) mice. Methods Different concentrations of FITC-dextran were used to compare the efficacy of this agent in perfusing the retinal vessels. Hematoxylin–eosin (HE) staining was used to evaluate the safety of RO injection. The vitreous blood vessels and extent of NV were assessed in P17 OIR mice using FITC-dextran and compared with the corresponding measurements obtained following isolectin B4 staining or the combination of both methods. Results The fluorescence of small vessels and neovascular tufts could be observed clearly following RO injection of 0.05 ml of 25 mg/ml or 50 mg/ml FITC-dextran. No visible damage to tissues adjacent to the injection site was discovered. Vitreous blood flow was gradually reduced from P0 to P5 and eventually disappeared in P17 OIR mice, as demonstrated by FITC-dextran perfusion. The retinal NV areas assessed by isolectin B4 were larger than those assessed by FITC-dextran, but the retinal avascular areas were smaller. The combination of both methods could conduce to distinguish non-functional blood vessels. Conclusions RO injection of FITC-dextran combined with isolectin B4 is an effective, optimal method for assessing the NV area and avascular area.

In traditional motor drive system, large volume electrolytic capacitors are utilized to buffer energy and stabilize the dc-link voltage. However, these capacitors affect the reliability of the drives and narrow the conduction angle of diode-rectifier. As a result, the grid side current is distorted and the power factor is deteriorated. In order to settle these issues, small dc-link capacitors can replace the electrolytic capacitors. In this paper, a motor torque control method with dc-link voltage feed-forward compensation for an interior permanent magnet synchronous motor (IPMSM) drive system is proposed. Hence, an integration multi-resonant (I-MR) controller is established to regulate the motor torque to obtain high input power factor and low grid current harmonics. In addition, a voltage feed-forward compensation is used to diminish the error of motor torque control. The effectiveness of the proposed method is verified through simulation and experiments. Results indicate that the input power factor can reach about 99.4% and the grid current harmonics are considerably lower than the requirement of EN-61000-3-2 standard.

Traumatic brain injury (TBI) as a pathogenetic factor in glioma remains controversial, and currently there is still no clear mechanism behind post-TBI glioma. Thus, we provide two case reports of post-TBI glioma contributing power to this research, and we provide a summary of the mechanisms of post-TBI glioma through literature review.We report two cases of brain gliomas that developed in the scar of a previous brain trauma. Both patients were male and both had suffered prior traumatic brain injuries (time interval 10-20 years), and postoperative pathological findings reported glioblastoma and WHO grade III glioma, respectively.These two cases further support the association of between traumatic brain injury and gliomas development.Although the epidemiological investigation between TBI and glioma is still controversial, there are still some important aspects here that can determine the possibility between TBI and gliomagenesis. Besides, we found that the reparative response of neural stem cells and the dysregulation of inflammatory cells are timportant theories of the mechanism of post-TBI glioma.

Compared to juvenile-onset best vitelliform macular dystrophy (BVMD), adult-onset BVMD is not well characterized and lacks strict diagnostic criteria. The present study aimed to evaluate the clinical and genetic characteristics of four advanced-age Chinese patients with adult-onset BVMD by combining multimodal imaging and genetic analysis. The four patients (all older than 50 years) were diagnosed with adult-onset BVMD at Zhongshan Ophthalmic Center (Guangzhou, China). Comprehensive ophthalmic examinations were performed, including analyses of best-corrected visual acuity, intraocular pressure, slit-lamp examination, fundus photography, optical coherence tomography, fundus fluorescein angiography and electrooculography. Genomic DNA was extracted from leukocytes isolated from peripheral blood obtained from these patients, their family members and 200 unrelated subjects from the same population. A total of 11 exons of the bestrophin-1 (BEST1) gene were amplified using PCR and sequenced. All of the four patients presented with lesions in the macular area. The patients were diagnosed with adult-onset BVMD based on multimodal imaging and genetic analysis. A total of four recurrent mutations, namely c.763C>T (p.Arg255Trp, p.R255W) in exon 7, c.584C>T (p.Ala195Val, p.A195V) in exon 5, c.910_912del GAT (p.304delAsp, p.D304del) in exon 8 and c.310G>C (p.Asp104His, p.D104H) in exon 4 of BEST1, were identified. Sorting intolerant from tolerant predicted that the amino acid substitutions p.R255W, p.A195V and p.D104H in the BEST1 protein were causing the damage. Combining multimodal imaging and genetic analysis was helpful in confirming the diagnosis of patients with adult-onset BVMD. These results maybe valuable for clinical and genetic counseling and for the development of therapeutic interventions for patients with BVMD.

In this work, a peptide-modified, biodegradable, nontoxic, brain-tumor-targeting nanoprobe based on superparamagnetic iron oxide nanoparticles (SPIONs) (which have been commonly used as T2-weighted magnetic resonance (MR) contrast agents) was successfully synthesized and applied for accurate molecular MR imaging and sensitive optical imaging. PEPHC1, a short peptide which can specifically bind to epidermal growth factor receptor variant III (EGFRvIII) that is overexpressed in glioblastoma, was conjugated with SPIONs to construct the nanoprobe. Both in vitro and in vivo MR and optical imaging demonstrated that the as-constructed nanoprobe was effective and sensitive for tumor targeting with desirable biosafety. Given its desirable properties such as a 100 nm diameter (capable of penetration of the blood–brain barrier) and bimodal imaging capability, this novel and versatile multimodal nanoprobe could bring a new perspective for elucidating intracranial glioblastoma preoperative diagnosis and the accuracy of tumor resection.

Objectives This study focused on investigating the expression and underlying molecular mechanism of early growth response 1 (Egr1) in diabetic retinopathy. Methods A microarray assay was applied to examine differentially expressed genes in the retina tissues of normal rats, as well as in those of streptozotocin‐induced diabetic rats. Human retinal vascular endothelial cells (HRVECs) transfected with sh‐NC, sh‐Egr1 or sh‐Egr1+ pVax1‐p53 were cultured under high‐glucose conditions and then used to explore the role of Egr1 in vitro. The effect of Egr1 on retinal vascular dysfunction caused by diabetes was examined by sh‐Egr1 administration in vivo Results Early growth response 1 was found to be up‐regulated in the retinas of diabetic rats compared to those of normal rats. Down‐regulation of Egr1 in HRVECs under high‐glucose conditions inhibited the apoptosis, migration and tube formation in vitro. Moreover, sh‐Egr1 partially reduced the injurious effects of hyperglycaemia on retinal vascular function by decreasing apoptotic cells and microvascular formation in vivo. The reduction of Egr1 evidently down‐regulated the p53 expression. Overexpression of p53 rescued the inhibition of sh‐Egr1 in HRVECs under high‐glucose concentration on apoptosis, migration and tube formation in vitro. Conclusion Down‐regulation of Egr1 partially reduced the injurious effects of hyperglycaemia on retinal vascular function via inhibiting p53 expression.

Background Accurately segment the tumor region of MRI images is important for brain tumor diagnosis and radiotherapy planning. At present, manual segmentation is wildly adopted in clinical and there is a strong need for an automatic and objective system to alleviate the workload of radiologists. Methods We propose a parallel multi-scale feature fusing architecture to generate rich feature representation for accurate brain tumor segmentation. It comprises two parts: (1) Feature Extraction Network (FEN) for brain tumor feature extraction at different levels and (2) Multi-scale Feature Fusing Network (MSFFN) for merge all different scale features in a parallel manner. In addition, we use two hybrid loss functions to optimize the proposed network for the class imbalance issue. Results We validate our method on BRATS 2015, with 0.86, 0.73 and 0.61 in Dice for the three tumor regions (complete, core and enhancing), and the model parameter size is only 6.3 MB. Without any post-processing operations, our method still outperforms published state-of-the-arts methods on the segmentation results of complete tumor regions and obtains competitive performance in another two regions. Conclusions The proposed parallel structure can effectively fuse multi-level features to generate rich feature representation for high-resolution results. Moreover, the hybrid loss functions can alleviate the class imbalance issue and guide the training process. The proposed method can be used in other medical segmentation tasks.

In IGBT power module, nearly 55% of the decrease of device reliability is caused by the increase of junction temperature. IGBT junction temperature estimation is a useful way to minimize failure rate. In this paper, three nonlinear machine learning-based models including Support Vector Regression (SVR), Random Forest (RF) and Back-Propagation Neural Network (BPNN) are constructed to automatically estimate the junction temperature under different parameter values. The simulation results are compared and prove that this machine learning method can be used and have a good prospect of industrial application.

Aims Diabetic retinopathy (DR) can cause vision loss in patients with diabetes. The present study evaluated the expression of thioredoxin interacting protein (TXNIP) and investigated the role of TXNIP in autophagy and apoptosis of DR. Main methods Reverse transcription-quantitative polymerase chain reaction (RT-qPCR) and western blotting were used to measure the expression level of the targets. Clustered regularly interspaced short palindromic repeats/CRISPR-associated 9 (CRISPR/cas9) method was applied for knockout of TXNIP. TdT-mediated dUTP Nick-End Labeling (TUNEL) assay and flow cytometry were utilized to detect the apoptosis. Cell Counting Kit-8 (CCK-8) assay was used to evaluate the cell viability. EdU assay was carried out to measure the cell proliferation ability. Retinal immunohistochemistry, retinal frozen section immunofluorescence as well as the electroretinogram (ERG) recording were implemented to detect the function of the retina. Key findings TXNIP was up-regulated under hyperglycemic condition both in vivo and in vitro. Overexpression of TXNIP activated the autophagy and apoptosis in the rat muller cell. Knockout of TXNIP reduced the autophagy and apoptosis in the rat muller cell under high glucose condition. TXNIP positively regulates autophagy via inhibition of the PI3K/AKT/mTOR signaling pathway. Knockdown of TXNIP improved the visual response to light stimulus of DR. Significance Our study unraveled for the first time that TXNIP positively regulates the autophagy in rat muller cell under high glucose condition by inhibiting the PI3K/AKT/mTOR signaling pathway, providing a novel understanding in the pathogenesis of DR and suggesting a potential new therapeutic target of DR.

Automated and accurate EGFR mutation status prediction using computed tomography (CT) imagery is of great value for tailoring optimal treatments to non-small cell lung cancer (NSCLC) patients. However, existing deep learning based methods usually adopt a single task learning strategy to design and train EGFR mutation status prediction models with limited training data, which may be insufficient to learn distinguishable representations for promoting prediction performance. In this paper, a novel multi-task learning method named AIR-Net is proposed to precisely predict EGFR mutation status on CT images. First, an auxiliary image reconstruction task is effectively integrated with EGFR mutation status prediction, aiming at providing extra supervision at the training phase. Particularly, we adequately employ multi-level information in a shared encoder to generate more comprehensive representations of tumors. Second, a powerful feature consistency loss is further introduced to constrain semantic consistency of original and reconstructed images, which contributes to enhanced image reconstruction and offers more effective regularization to AIR-Net during training. Performance analysis of AIR-Net indicates that auxiliary image reconstruction plays an essential role in identifying EGFR mutation status. Furthermore, extensive experimental results demonstrate that our method achieves favorable performance against other competitive prediction methods. All the results executed in this study suggest that the effectiveness and superiority of AIR-Net in precisely predicting EGFR mutation status of NSCLC.

In this paper, an improved sensorless vector control method for an interior permanent magnet synchronous motor (IPMSM) drive with small DC-link capacitors is proposed. First, a fast sliding-mode observer was applied, to enlarge the observer bandwidth. Then, an improved estimator based on a proportional integral resonant controller was designed for the estimate speed shaping, which means the actual speed can be tracked. This not only reduces the position estimate error, but also enhances the grid power factor and suppresses the input current harmonics. Simulation and experiments were conducted on a sensorless IPMSM drive system with a small film capacitor. The effectiveness of the proposed estimation method was verified by the simulation and experimental results. The estimated error was reduced and the grid current harmonics satisfy the requirements of EN61000-3-2.

The stability regions of a LCL-filtered converter adopting converter-current-feedback control without damping are analyzed. The nonlinear LCL-filtered model is presented to investigate its influence on the system stability. The stability analysis is performed by means of the Nyquist diagram in s domain. It reveals that three factors have the dominant effects on the system stability, including internal loss of LCL-filtered model, PWM transport delay and controller parameters. The undamped stability boundaries of the system gain calculated by the symmetrical optimum method are obtained. It can be found that stable regions for the nonlinear LCL-filtered system are extended into a continuous region of ratios of LCL filter resonance frequency to control frequency from three distinct regions. Finally, the stable regions are validated by the nonlinear model simulation, and experimental results verify the theoretical analysis.

Familial exudative vitreoretinopathy (FEVR) is a rare hereditary retinal disorder characterized by the premature arrest of vascularization in the peripheral retina. The aim of the present study was to characterize the clinical presentations of a Chinese family affected by bilateral severe FEVR, and to identify the underlying genetic variations. One family that presented with bilateral FEVR was recruited for this study. Comprehensive ophthalmic examinations, including best‑corrected visual acuity, slit‑lamp examination, fundus photography, fundus fluorescein angiography imaging and electroretinogram were performed. Genomic DNA was extracted from leukocytes of the peripheral blood collected from the affected and unaffected family members, as well as 200 unrelated control subjects from the same population. Next‑generation sequencing of the candidate genes associated with ocular diseases was performed, and the identified mutations were validated by conventional polymerase chain reaction‑based sequencing. The functional effects of the mutations were analyzed by polymorphism phenotyping (PolyPhen) and sorting intolerant from tolerant (SIFT). One heterozygous ATP binding cassette subfamily A member 4 (ABCA4) c.5693G>A (p.R1898H) mutation in exon 40 and one heterozygous LDL receptor related protein 5 (LRP5) c.260T>G (p.I87S) mutation in exon 2 were identified in this family. To the best of our knowledge, the ABCA4 c.5693G>A (p.R1898H) mutation has not been reported in FEVR, and the LRP5 c.260T>G (p.I87S) mutation is a novel mutation. PolyPhen and SIFT predicted that the amino acid substitution R1898H in protein ABCA4 is benign, whereas the amino acid substitution I87S in protein LRP5 is damaging. A single nucleotide polymorphism c.266A>G (p.Q89R, rs41494349) was identified in exon 2 of LRP5. These findings expand the mutation spectrums of ABCA4 and LRP5, and will be valuable for genetic counseling and development of therapeutic interventions for patients with FEVR.

The aim of the present study was to identify mutations in the fibroblast growth factor receptor 2 (FGFR2) gene in patients with Crouzon syndrome and characterize the associated clinical features. A total of two Chinese patients diagnosed with Crouzon syndrome underwent complete examinations, including best-corrected visual acuity, slit-lamp, examination, fundus examination, optical coherence tomography and computed tomography of the skull. Genomic DNA was extracted from peripheral blood samples collected from the patients, as well as their family members and 200 unrelated control subjects from the same population. Exons 8 and 10 in the FGFR2 gene were amplified by polymerase chain reaction and directly sequenced. Patient #1 had a heterozygous missense mutation (c.1025G>A, p.C342Y) in exon 10 of FGFR2. Patient #2 had a heterozygous mutation (c.1084+1 G>T; IVS10+1G>T) in intron 10. The mutations were not present in any of the unaffected family members or unrelated control subjects. These findings expand the mutation spectrum of FGFR2, and are valuable for genetic counseling in addition to prenatal diagnosis in patients with Crouzon syndrome.

The blood-brain barrier is a formidable obstacle for glioma chemotherapy due to its compact structure and drug efflux ability. In this study, a dual-targeting drug delivery system involving Angiopep-2-conjugated biodegradable polymersomes loaded with doxorubicin (Ang-PS-DOX) was developed to exploit transport by the low-density lipoprotein receptor-related protein 1 (LRP1), which is overexpressed in both blood-brain barrier and glioma cells. The polymersomes (PS) were prepared using a thin-film hydration method. The PS were loaded with doxorubicin using the pH gradient method (Ang-PS-DOX). The resulting PS were uniformly spherical, with diameters of ~135 nm and with ~159.9 Angiopep-2 molecules on the surface of each PS. The drug-loading capacity and the encapsulation efficiency for doxorubicin were 7.94%±0.17% and 95.0%±1.6%, respectively. Permeability tests demonstrated that the proton diffusion coefficient across the PS membrane was far slower than that across the liposome membrane, and the common logarithm value was linearly dependent on the dioxane content in the external phase. Compared with PS-DOX, Ang-PS-DOX demonstrated significantly higher cellular uptake and stronger cytotoxicity in C6 cells. In vivo pharmacokinetics and brain distribution experiments revealed that Ang-PS-DOX achieved a more extensive distribution and more abundant accumulation in glioma cells than PS-DOX. Moreover, the survival time of glioma-bearing rats treated with Ang-PS-DOX was significantly prolonged compared with those treated with PS-DOX or a solution of free doxorubicin. These results suggested that Ang-PS-DOX can target glioma cells and enhance chemotherapeutic efficacy.

Photodynamic therapy (PDT) is a non-invasive therapy with many advantages over other therapeutic methods, but it is restricted to treat superficial cancers due to the shallow tissue penetration of visible light. The biological window in the near infrared region (NIR) offers hope to extend the penetration depth, but there is no natural NIR excited photosensitizer. Here, we report a novel photosensitizer: NaYbF4 nanoparticles (NPs). By using a 1,3-diphenylisobenzofuran (DPBF) sensor, we show that the Yb3+ ions can absorb the NIR light and transfer energy directly to oxygen to generate reactive oxygen species (ROS). The efficiency of transferring energy to oxygen by NaYbF4 NPs is comparable to that of traditional photosensitizers. We have carried out PDT both in vitro and in vivo based on NaYbF4 NPs; the results demonstrate that NaYbF4 NPs are indeed an effective NIR photosensitizer, which can help extend the application of PDT to solid tumors owing to the much deeper penetration depth of NIR light.

Recently, biomimetic nanoparticles, especially cell membrane-cloaked nanoparticles, have attracted increasing attention in biomedical applications, including antitumor therapy, detoxification, and immune modulation, by imitating the structure and the function of biological systems such as long circulation life in the blood. However, the circulation time of cell membrane-cloaked nanoparticles is far less than that of the original cells, greatly limiting their biomedical applications, while the underlying reasons are seldom demonstrated. In this study, the influence of particle size on the circulation and the biodistribution of red blood cell membrane-coated nanoparticles (RBC-NPs) as model biomimetic nanoparticles were investigated. Differently sized RBC-NPs (80, 120, 160, and 200 nm) were prepared by fusing RBC membranes on poly(lactic-co-glycolic acid) nanoparticles. It was shown that the particle size did not change the cellular uptake of these biomimetic nanoparticles by macrophage cells in vitro and their immunogenic responses in vivo. However, their circulation life in vivo decreased with the particle size, while their accumulation in the liver increased with the particle size, which might be related to their size-dependent filtration through hepatic sinusoids. These findings will provide experimental evidence for the design and the optimization of biomimetic nanoparticles.

Traditional variable speed motor drive system utilizes large volume electrolytic capacitor to buffer energy and stabilize the dc-link voltage, which narrows the conduction angle of diode-rectifier. As a result, the grid side current is distorted and the power factor is deteriorated. In order to settle these issues, a motor torque control method based on the relationship between inverter power and motor torque is proposed, and high power factor control of reduced dc-link capacitance IPMSM drive system is realized. An integration quasi-resonant (IQR) controller is established to regulate the motor torque. Effectiveness of the proposed method is verified through simulation and experiments, and the harmonics of grid side current can be reduced under the limits of IEC61000-3-2.

Pore-forming toxins (PFTs) are the most common bacterial virulence proteins and play a significant role in the pathogenesis of bacterial infections; thus, PFTs are an attractive therapeutic target in bacterial infections. Inspired by the pore-forming process and mechanism of PFTs, we designed an integrated hybrid nanovesicle-the erythroliposome (called the RM-PL)-for PFT detoxification by fusing natural red blood cell (RBC) membranes with artificial lipid membranes. The lipid and RBC membranes were mutually beneficial when integrated into a hybrid nanovesicle structure. The RBC membrane endowed RM-PLs with the capacity for detoxification, while the PEGylated lipid membrane stabilized the RM-PLs and greatly improved the detoxification capacity of the RBC membrane. With α-hemolysin (Hlα) as a model PFT, we demonstrated that RM-PLs could not only significantly reduce the toxicity of Hlα to erythrocytes in vitro but also effectively sponge Hlα in vivo and rescue mice from Hlα-induced damage. Moreover, the high detoxification capacity of RM-PLs was shown to be partly related to the expression of the Hlα receptor protein, a disintegrin and metalloproteinase domain-containing protein 10 on the RBC membrane. Consequently, as a component integrating natural and artificial materials, the erythroliposome nanoplatform inspires potential strategies for antivirulence therapy.

Unlike the United States, where human papillomavirus (HPV) vaccines have been available for decades, China recently approved its first HPV vaccines. Setting up a baseline comparison between these two countries, this study examines the influence of message framing, motivational orientation, cultural worldview, knowledge, and gender on young adults' intentions to get vaccinated. Compared to the U.S. participants, Chinese participants perceived HPV as a more severe risk and were more willing to get the vaccine. However, they were also more skeptical about vaccine safety. Inconsistencies with previous research emerged regarding the moderating effects of motivational orientation and cultural worldview. Findings from this study offer important implications for HPV vaccine promotion in China.

Congenital aniridia is a rare genetic disorder characterized by a variable degree of hypoplasia or absence of iris. It is frequently associated with keratopathy, cataract, juvenile-onset glaucoma and foveal and optic nerve hypoplasia. Mutations in the Paired Box 6 (PAX6) gene on chromosome 11p13 have been demonstrated to cause aniridia. The aim of the present study was to investigate the genetic variations of PAX6 in two sporadic patients from southern China with classic congenital aniridia and cataract. Complete ophthalmic and physical examinations were performed, including best-corrected visual acuity, intraocular pressure, slit-lamp examination, fundus examination, optical coherence tomography, ultrasound biomicroscopy, and Pentacam scanning. Genomic DNA was extracted from leukocytes of peripheral blood collected from the two patients, their unaffected parents and 200 unrelated control subjects from the same population. Exons 4–13 of the PAX6 gene were amplified by polymerase chain reaction and sequenced directly. Patient 1 was affected with aniridia accompanied by congenital cataract and nystagmus. A novel heterozygous PAX6 frameshift mutation c.277delG (p.Glu93SerfsX31) in exon 6 was identified in this patient. Patient 2 was presented with aniridia, congenital cataract, lens subluxation and glaucoma. A recurrent nonsense mutation c.718C>T (p.Arg240X) in exon 9 was identified in this patient. The present results expand the mutation spectrum of PAX6 and will be valuable for genetic counseling in the affected families. Additionally, the identification of these mutations reiterates the importance of PAX6 in ocular development and sheds light on the pathogenesis of congenital aniridia.

Accurate brain magnetic resonance imaging (MRI) tumor segmentation continues to be an active research topic in medical image analysis since it provides doctors with meaningful and reliable quantitative information in diagnosing and monitoring neurological diseases. Successful deep learning-based proposals have been designed, and most of them are built upon image patches. In this paper, a novel end-to-end brain tumor segmentation method is developed using an improved fully convolutional network by modifying the U-Net architecture. In our network, an innovative structure referred to as an up skip connection is first proposed between the encoding path and decoding path to enhance information flow. Moreover, an inception module is adopted in each block to help our network learn richer representations, and an efficient cascade training strategy is introduced to segment brain tumor subregions sequentially. In contrast to those patchwise methods, our model can automatically generate segmentation maps slice by slice. We have validated our proposal by using imaging data from the Multimodal Brain Tumor Image Segmentation Challenge (BRATS) 2015 and BRATS 2016. Experimental results compared with U-Net suggest that our method is 2.6%, 3.9%, and 5.2% higher (by using the BRATS 2015 training dataset) as well as 2.8%, 3.7%, and 8.1% (by using the BRATS 2017 training dataset) higher in terms of complete, core and enhancing tumor regions, respectively. Quantitative and visual evaluation of our method has revealed the effectiveness of the proposed improvements and indicated that our end-to-end segmentation method can achieve a performance that can compete with state-of-the-art brain tumor segmentation approaches.

Stickler syndrome is a group of inherited connective tissue disorders characterized by distinctive facial and ocular abnormalities, hearing loss and early-onset arthritis. The aim of the present study was to investigate the genetic changes in two Chinese patients with Stickler syndrome, manifested as bilateral retinal detachment and peripheral retinal degeneration. Complete ophthalmic examinations, including best-corrected visual acuity, slit-lamp examination and fundus examination, were performed. Genomic DNA was extracted from leukocytes of the peripheral blood collected from the patients, their unaffected family members and 200 unrelated control subjects from the same population. Next-generation sequencing of established genes associated with ocular disease was performed. A heterozygous collagen type II α1 chain (COL2A1) mutation c.1310G>C (p.R437P) in exon 21 was identified in Family 1 and a heterozygous COL2A1 mutation c.2302-1G>A in intron 34 was identified in Family 2. The functional effects of the mutations were assessed by polymorphism phenotyping (PolyPhen) and sorting intolerant from tolerant (SIFT) analysis. The c.1310G>C mutation was predicted to damage protein structure and function, and the c.2302-1G>A mutation was predicted to result in a splicing defect. The findings of the current study expand the established mutation spectrum of COL2A1, and may facilitate genetic counseling and development of therapeutic strategies for patients with Stickler syndrome.