Search

Study Design Comparative study Objective To compare manual and deep learning-based automated measurement of Cobb angle in adolescent idiopathic scoliosis. Methods We proposed a fully automated framework to measure the Cobb angle of AIS patients. Whole-spine images of 500 AIS individuals were collected. 200 digital radiographic (DR) images were labeled manually as training set, and the remaining 300 images were used to validate by mean absolute error (MAE), Pearson or spearman correlation coefficients, and intra/interclass correlation coefficients (ICCs). The relationship between accuracy of vertebral boundary identification and the subjective image quality score was evaluated. Results The PT, MT, and TL/L Cobb angles were measured by the automated framework within 300 milliseconds. Remarkable 2.92° MAE, .967 ICC, and high correlation coefficient (r = .972) were obtained for the major curve. The MAEs of PT, MT, and TL/L were 3.04°, 2.72°, and 2.53°, respectively. The ICCs of these 3 curves were .936, .977, and .964, respectively. 88.7% (266/300) of cases had a difference range of ±5°, with 84.3% (253/300) for PT, 89.7% (269/300) for MT, and 93.0% (279/300) for TL/L. The decreased bone/soft tissue contrast (2.94 vs 3.26; P=.039) and bone sharpness (2.97 vs 3.35; P=.029) were identified in the images with MAE exceeding 5°. Conclusion The fully automated framework not only identifies the vertebral boundaries, vertebral sequences, the upper/lower end vertebras and apical vertebra, but also calculates the Cobb angle of PT, MT, and TL/L curves sequentially. The framework would shed new light on the assessment of AIS curvature.

Understanding the influence of fine atmospheric particles (PM

The appropriate translocation speed of a single-stranded DNA (ssDNA) through a solid-state nanopore is crucial for DNA sequencing technologies. By studying the geometry effect of graphene-MoS

Objective To build a model for proximal junctional kyphosis (PJK) prognostication in Lenke 5 adolescent idiopathic scoliosis (AIS) patients undergoing long posterior instrumentation and fusion surgery by machine learning and analyze the risk factors for PJK. Materials and methods In total, 44 AIS patients (female/male: 34/10; PJK/non-PJK: 34/10) who met the inclusion criteria between January 2013 and December 2018 were retrospectively recruited from West China Hospital. Thirty-seven clinical and radiological features were acquired by two independent investigators. Univariate analyses between PJK and non-PJK groups were carried out. Twelve models were built by using four types of machine learning algorithms in conjunction with two oversampling methods [the synthetic minority technique (SMOTE) and random oversampling]. Area under the receiver operating characteristic curve (AUC) was used for model discrimination, and the clinical utility was evaluated by using F1 score and accuracy. The risk factors were simultaneously analyzed by a Cox regression and machine learning. Results Statistical differences between PJK and non-PJK groups were as follows: gender (p = 0.001), preoperative factors [thoracic kyphosis (p = 0.03), T1 slope angle (T1S, p = 0.078)], and postoperative factors [T1S (p = 0.097), proximal junctional angle (p = 0.003), upper instrumented vertebra (UIV) - UIV + 1 (p = 0.001)]. Random forest using SMOTE achieved the best prediction performance with AUC = 0.944, accuracy = 0.909, and F1 score = 0.667 on independent testing dataset. Cox model revealed that male gender and larger preoperative T1S were independent prognostic factors of PJK (odds ratio = 10.701 and 57.074, respectively). Gender was also at the first place in the importance ranking of the model with best performance. Conclusion The random forest using SMOTE model has the great value for predicting the individual risk of developing PJK after long instrumentation and fusion surgery in Lenke 5 AIS patients. Moreover, the combination of the outcomes of a Cox model and the feature ranking extracted by machine learning is more valuable than any one alone, especially in the interpretation of risk factors.

Toxic abnormal aggregation of α-synuclein (α-Syn) is a feature of Parkinson’s disease. Several biochemical and biophysical studies have demonstrated that many post-translational modifications (PTM) of α-Syn could distinctly alleviate its oligomerization-mediated toxicity. Recently, a compelling link is emerging between the PTM O-GlcNAcylation (O-GlcNAc) and protein aggregation, yet the underlying molecular mechanism remains unclear. Based on the all-atom molecular dynamics simulations, we found that O-GlcNAc modifications can suppress the process of oligomerization of α-Syn aggregates via a steric effect—the additional O-linked glycosyl group disrupts the formation of hydrogen bonds (H-bonds) between α-Syn monomers. Besides, we proposed a theoretical model to further capture the physical mechanism of α-Syn aggregation/disaggregation in the absence/presence of O-GlcNAc-modified α-Syn. Our findings unveil the molecular mechanism of the O-GlcNAc-induced inhibition of α-Syn oligomerization, which may help to understand how O-GlcNAc prevents the oligomerization of other proteins and provides the guideline for the development of O-GlcNAc-based therapeutic strategies in neurodegenerative diseases.

Background Previous studies have reported the progression of deformity in patients with adolescent idiopathic scoliosis after implant removal. However, for patients with congenital scoliosis, few studies have investigated the prognosis after implant removal. Methods We observed 24 patients with congenital scoliosis, who underwent implant removal, for at least 3 years. Radiographic parameters and demographic data were compared to evaluate whether implant removal would lead to deformity progression. Results Four of the 24 patients (16.7%) suffered correction loss and underwent revision surgery (RS). All correction losses occurred within 12 months of implant removal. The average curve of fixed segments (9.84° ± 7.22° to 16.42° ± 16.79°; P = 0.017) and kyphosis of fixed segments (10.46° ± 13.42° to 18.98° ± 25.99°; P = 0.03) increased significantly throughout the follow-up. After excluding patients who underwent RS, the changes in curve of fixed segments (9.10°–11.58°) and kyphosis of fixed segments (8.50°–9.24°) were all within the measurement error. The coronal and sagittal balance maintained during the follow-up. Through comparison, we thought that the younger age and lower Risser’s grade with larger scoliosis might be risk factors for correction loss. Conclusions Implant removal after fusion surgery for congenital scoliosis may present loss of correction and require RS, thus preserving implants is recommended. When removal of instrumentation is inevitable, parents and patients should be counseled for potential loss of correction and RS, and patients should be monitored for the progression of deformity.

Hepatocellular carcinoma (HCC) is one of the most common and most lethal malignant tumors in the world. Microvascular invasion (MVI) is a major risk factor for survival outcomes and intrahepatic metastasis after resection in patients with HCC. Relevant English literatures retrieved using PubMed on the research progress of MVI in patients with HCC were reviewed. For HCC patients, especially those with MVI, it is very important to develop a comprehensive and sequential treatment plan to support the long-term survival of patients. This manuscript reviewed and analyzed the risk factors for MVI; the preoperative prediction of MVI, which informs the selection of surgical strategies; and the current situation and future direction of comprehensive postoperative treatment strategies; to provide a basis for the comprehensive treatment of HCC patients with MVI. For HCC patients with MVI, the preoperative prediction of MVI may play a certain guiding role in planning procedures, and the comprehensive sequential postoperative pathological detection of HCC MVI may provide a basis for treatment decisions.

3D-printed titanium alloy orthopedic implants combine the dual advantages of 3D printing and titanium alloys implants, which not only have complex structures that cannot be manufactured by traditional techniques, but also inherit the excellent physical and chemical properties of titanium and its alloys, so they are widely used in the field of orthopedics in recent years. The inherent porous structure of 3D-printed implants and the original modification processes of titanium alloys provide the conditions for the functionalization of implants. To meet the needs of orthopedic surgeons and patients, functionalized implants with the ability of long-term stability promotion, anti-infection or anti-tumor have been developed, in which various methods of functionalization deserve to be summarized, compared and analyzed. Therefore, in this review, we will collect the existing knowledge on functionalization of 3D-printed titanium alloy orthopedic implants and give our own opinion.

The phytoplankton and zooplankton biomass as well as nutrients in the southern region of Kuroshio Extension (KE) presents obvious decadal variability. Both local and remote links between biomass and physical properties are investigated by comparing satellite observations and the outputs from a biological-physical coupled model. The Regional Ocean Model System (ROMS) and Carbon, Silicate, and Nitrogen Ecosystem (CoSiNE) cover the entire Pacific Ocean. The ROMS-CoSiNE model captures the spatial distribution and decadal variation of the key biological variables including phytoplankton and zooplankton biomass and nutrients in the upper ocean around the KE. The decadal variation in the region is mainly caused by the westward-propagating signals that originate from the central and eastern North Pacific. Specifically, these signals are induced by the decadal oscillation of vertical displacement related to large-scale decadal Pacific modes, such as the North Pacific Gyre Oscillation (NGPO).The evidence obtained here includes not only from surface variables (sea surface height and surface chlorophyll) but also from the variables in the deeper ocean (thermocline, subsurface nutrients, upper 100-m phytoplankton and zooplankton biomass) in the KE region. The signals of the variables in the southern KE region significantly lag that of the NPGO in the central and eastern North Pacific by about 2-4 years. The mixed layer nitrogen budget is conducted to evaluate the contribution of vertical and horizontal advection for the decadal variation of nutrients.

The predecessor of endoscopic surgery, arthroscopic microdiscectomy (AMD) was first introduced to China in the 1990s after its introduction in Japan, Germany and the United States in the 1980s (1-3).

Hepatocellular carcinoma (HCC) is regarded as a leading cause of cancer-related deaths, and its progression is associated with hypoxia and the induction of hypoxia-inducible factor (HIF). Meloxicam, a selective cyclooxygenase-2 (COX-2) inhibitor, induces cell death in various malignancies. However, the underlying mechanism remains to be elucidated in HCC, especially under hypoxic conditions. The alteration of COX-2 and HIF-1α oncogenicity was evaluated in HCC specimens by tissue microarray. Cell viability, angiogenesis assays, and xenografted nude mice were used to evaluate the effects of meloxicam, along with flow cytometry to detect the cell cycle, apoptosis, and mitochondrial membrane potential (ΔΨm) of HCC. qRT-PCR, Western blotting, immunofluorescence, immunohistochemistry, luciferase assay, and RNAi were carried out to determine the HIF-1α signaling affected by meloxicam. In this study, we showed that meloxicam exerts antiproliferative and antiangiogenesis efficacy in vitro and in vivo and causes disruption of mitochondrial membrane potential (ΔΨm), thus leading to caspase-dependent apoptosis under hypoxic environments. Exposure to meloxicam significantly reduced HIF-1α transcriptional activation and expression through sequestering it in the cytoplasm and accelerating degradation via increasing the von Hippel-Lindau tumor suppressor protein (pVHL) in HCC. These data demonstrated that inhibition of HIF-1α by meloxicam could suppress angiogenesis and enhance apoptosis of HCC cells. This discovery highlights that COX-2 specific inhibitors may be a promising therapy in the treatment of HCC.

MAO-treated porous Ti6Al4V holds enormous potential for use in orthopedic implants due to their excellent biocompatibility and favourable mechanical strength. However, the effects on the V ion accumulation and release following the MAO-treated Ti6Al4V remain undetermined. The aim of the present study was to assess the effects of Vanadium on biocompatibility. In this study, the surface features and chemical compositions were characterized by scanning electron microscopy (SEM), energy-dispersive X-ray spectrometry (EDS) and X-ray photoelectron spectroscopy (XPS). The ion release of Ti, Al and V was quantitatively measured by inductively-coupled plasma mass spectroscopy (ICP-MS) after immersion in Hanks' solution. To probe the mechanism of V release, the corrosion resistance of porous Ti6Al4V before and after the MAO process was evaluated by electrochemical tests. Thereafter, the effects on the biocompatibility were tested in vitro by cell culture assays and then in vivo by subcutaneous embedment. Finally, the bone tissue response and in vivo release profile of V ions were characterized by intra-osseous implantation. Therefore, this study suggests that the effect of V released from MAO-treated porous Ti6Al4V on biocompatibility and application safety is small and preventable.

In order to maximize the exploited wind power and benefit from a wide range of the wind speed, a novel combined maximum power point tracking (MPPT)-Pitch angle control is developed based on Neural Network (ANN), in order to solve the previous control strategy, heavy workload, complicated process and other issues. It allows the generator to work at the optimum speed when the wind speed is below the rated wind speed, and output the constant power when wind speed is higher than the rated wind speed. The whole process is realized by an artificial neural network controller. Based on Matlab, establish a variable speed constant frequency doubly fed wind turbine model. Simulation and analysis of the wind speed range changes near the rated, using combined maximum power point tracking (MPPT) - pitch control strategy can achieve fast and accurate tracking and constant output power, and has good dynamic performance and fast tracking characteristic.

Objective The purposes of the present study were to introduce an indirect decompression using oblique lateral lumbar interbody fusion combined with anterolateral screw fixation (OLIF-AF) for the treatment of lumbar degenerative disc disease and examine the clinical efficacy and radiographic outcomes. Methods A total of 65 patients had undergone single-level OLIF-AF at L2–L5 from December 2017 to August 2018. The cross-sectional area of the thecal sac was evaluated using magnetic resonance imaging. The disk height, foraminal height (FH), and degree of upper vertebral slippage were evaluated using computed tomography. The visual analog scale score and Oswestry disability index were recorded pre- and postoperatively. Results The visual analog scale scores and Oswestry disability index had significantly improved after surgery (P 0.05). Adverse events were observed in 15 patients (23.1%) patients and included pain at the iliac bone donor site in 1 (1.5%), left thigh pain/numbness in 2 (3.1%), quadriceps weakness in 2 (3.1%), psoas weakness in 3 (4.6%), intraoperative endplate injury in 2 (3.1%) and cage subsidence in 5 (7.7%). Conclusions Our results have shown that OLIF-AF surgery is a relatively safe and effective surgical option for LDDD at L2–L5. Cage subsidence was the most common operative complication.

The paper aimed at exploring the current phenomenon regarding human translation with machine translation. Human translation (HT), by definition, is when a human translator—rather than a machine—translate text. It's the oldest form of translation, relying on pure human intelligence to convert one way of saying things to another. The person who performs language translation. Learn more about using technology to reduce healthcare disparity. A person who performs language translation. The translation is necessary for the spread of information, knowledge, and ideas. It is absolutely necessary for effective and empathetic communication between different cultures. Translation, therefore, is critical for social harmony and peace. Only a human translation can tell the difference because the machine translator will just do the direct word to word translation. This is a hindrance to machines because they are not advanced to the level of rendering these nuances accurately, but they can only do word to word translations. There are different translation techniques, diverse theories about translation and eight different translation services types, including technical translation, judicial translation and certified translation. The translation is the process of translating the sequence of a messenger RNA (mRNA) molecule to a sequence of amino acids during protein synthesis. The genetic code describes the relationship between the sequence of base pairs in a gene and the corresponding amino acid sequence that it encodes.

The concept of the binary sequence pair is generalized from a single binary sequence. Binary sequence pairs are applied in many fields of radar, sonar or communication systems, in which signals with optimal periodic correlation are required. Several types of almost perfect binary sequence pairs of length T = 2q are constructed, where q is an odd number. These almost perfect binary sequence pairs are based on binary ideal sequence or binary ideal two-level correlation sequence pairs by using Chinese remainder theorem. For these almost perfect binary sequence pairs with good balanced property, their corresponding divisible difference set pairs (DDSPs) are also derived.

Coastal upwelling ecosystems are among the most productive ecosystems in the world, meaning that their response to climate change is of critical importance. Our understanding of climate change impacts on marine ecosystems is largely limited to the open ocean, mainly because coastal upwelling is poorly reproduced by current earth system models. Here, a high-resolution model is used to examine the response of nutrients and plankton dynamics to future climate change in the California Current System (CCS). The results show increased upwelling intensity associated with stronger alongshore winds in the coastal region, and enhanced upper-ocean stratification in both the CCS and open ocean. Warming of the open ocean forces isotherms downwards, where they make contact with water masses with higher nutrient concentrations, thereby enhancing the nutrient flux to the deep source waters of the CCS. Increased winds and eddy activity further facilitate upward nutrient transport to the euphotic zone. However, the plankton community exhibits a complex and nonlinear response to increased nutrient input, as the food web dynamics tend to interact differently. This analysis highlights the difficulty in understanding how the marine ecosystem responds to a future warming climate, given to range of relevant processes operating at different scales.

The refractive index (RI) of a sample as an endogenous contrast agent plays an important role in transparent live cell imaging. In tomographic phase microscopy (TPM), 3D quantitative RI maps can be reconstructed based on the measured projections of the RI in multiple directions. The resolution of the RI maps not only depends on the numerical aperture of the employed objective lens, but also is determined by the accuracy of the quantitative phase of the sample measured at multiple scanning illumination angles. This paper reports an analogous on-axis interference TPM, where the interference angle between the sample and reference beams is kept constant for projections in multiple directions to improve the accuracy of the phase maps and the resolution of RI tomograms. The system has been validated with both silica beads and red blood cells. Compared with conventional TPM, the proposed system acquires quantitative RI maps with higher resolution (420 nm @λ = 633 nm) and signal-to-noise ratio that can be beneficial for live cell imaging in biomedical applications.

Purpose: Systemic therapy has often been used for patients with advanced hepatocellular carcinoma (HCC). However, due to drug resistance, the use of cytotoxic chemotherapy in the treatment of patients with advanced HCC has typically demonstrated low response rates. Secretory clusterin (sCLU) is expressed in aggressive late-stage tumors and associated with resistance to chemotherapy, including that in HCC cases. The present research aimed to investigate the biological role of sCLU in HCC. Methods: sCLU expression in HCC and normal tissues was examined using immunohistochemical staining, followed by analysis of the correlation between sCLU expression and clinical indicators. In addition, the role and internal mechanism of sCLU in cell proliferation and apoptosis were investigated in HCC cells. Results: sCLU expression was significantly upregulated in HCC tissues; and was associated with histological grade and poor overall survival. The levels of sCLU were significantly increased in Bel7402, SMMC7721 and resistant HCC cells (Bel7404-OR). Inhibiting the activity of sCLU enhanced the chemosensitivity of Bel7402 and SMMC7721 cells. Downregulation of sCLU could increase the expression of Gadd45a in HCC cells. Overexpression of sCLU contributed to drug resistance in Bel7402, SMMC7721 and Bel7404-OR cells; whereas, overexpression of Gadd45a alone overcame drug resistance in the cells above. No significant expression changes of sCLU and Gadd45a were observed in HCC cells after the interference of a selective inhibitor of the PI3K/Akt signaling pathway. However, regulation of the expression of Gadd45a could influence the phosphorylation level of Akt; and further regulate the expression of Bcl-2 and Bax proteins involved in the mitochondrial apoptosis pathways. Conclusions: The results demonstrate that sCLU/Gadd45a/PI3K/Akt signaling represents a novel pathway that could regulate drug resistance in a one-way manner in HCC cells.

The cause for large variability of hypoxia off the Changjiang Estuary has not been well understood partly due to various nutrient sources and complex physical-biological processes involved. The Regional Ocean Modeling Systems (ROMS) coupled with Carbon, Silicate and Nitrogen Ecosystem (CoSiNE) was used to investigate the 2006 hypoxia in the East China Sea, the largest hypoxia ever recorded. The model performance was evaluated comprehensively by comparing a suite of quantitative metrics, procedures and spatiotemporal patterns between the simulated results and observed data. The simulated results are generally consistent with the observations and are capable of reproducing the development of hypoxia and the observed vertical profiles of dissolved oxygen. Event-scale reduction of hypoxia occurred during the weakening of stratification in mid-July and mid-September, due to strong stirring caused by tropical storms or strong northerly wind. Change in wind direction altered the pathway of Changjiang Diluted Water and consequently caused variation in hypoxic location. Increase in river discharge led to an expansion of hypoxic water during the summer monsoon. Sensitivity analysis suggested that the hypoxia extent was affected by the change in nutrient concentration of the Changjiang as well as that of the Kuroshio. Sensitivity analysis also suggested the importance of sediment oxygen consumption to the size of the hypoxic zone. These results demonstrate that a prognostic 3D model is useful for investigating the highly variable hypoxia, with comprehensive considerations of multiple factors related to both physical and biological processes from the estuary to the shelf break of the East China Sea.

Total internal reflection fluorescence microscopy (TIRFM) provides high optical sectioning capability and superb signal-to-noise ratio for imaging of cell cortex structures. The development of multi-angle (MA)-TIRFM permits high axial resolution imaging and reconstruction of cellular structures near the cell surface. Cytoskeleton is composed of a network of filaments, which are important for maintenance of cell function. The high-resolution imaging and quantitative analysis of filament organization would contribute to our understanding of cytoskeleton regulation in cell. Here, we used a custom-developed MA-TIRFM setup, together with stochastic photobleaching and single molecule localization method, to enhance the lateral resolution of TIRFM imaging to about 100 nm. In addition, we proposed novel methods to perform filament segmentation and 3D reconstruction from MA-TIRFM images. Furthermore, we applied these methods to study the 3D localization of cortical actin and microtubule structures in U373 cancer cells. Our results showed that cortical actins localize ∼ 27 nm closer to the plasma membrane when compared with microtubules. We found that treatment of cells with chemotherapy drugs nocodazole and cytochalasin B disassembles cytoskeletal network and induces the reorganization of filaments towards the cell periphery. In summary, this study provides feasible approaches for 3D imaging and analyzing cell surface distribution of cytoskeletal network. Our established microscopy platform and image analysis toolkits would facilitate the study of cytoskeletal network in cells.