CDDnet: Cross-domain denoising network for low-dose CT image via local and global information alignment

The domain shift problem has emerged as a challenge in cross-domain low-dose CT (LDCT) image denoising task, where the acquisition of a sufficient number of medical images from multiple sources may be constrained by privacy concerns. In this study, we propose a novel cross-domain denoising network (CDDnet) that incorporates both local and global information of CT images. To address the local component, a local information alignment module has been proposed to regularize the similarity between extracted target and source features from selected patches. To align the general information of the semantic structure from a global perspective, an autoencoder is adopted to learn the latent correlation between the source label and the estimated target label generated by the pre-trained denoiser. Experimental results demonstrate that our proposed CDDnet effectively alleviates the domain shift problem, outperforming other deep learning-based and domain adaptation-based methods under cross-domain scenarios.

EEGDnet: Fusing non-local and local self-similarity for EEG signal denoising with transformer

Electroencephalogram (EEG) has shown a useful approach to produce a brain-computer interface (BCI). One-dimensional (1-D) EEG signal is yet easily disturbed by certain artifacts (a.k.a. noise) due to the high temporal resolution. Thus, it is crucial to remove the noise in received EEG signal. Recently, deep learning-based EEG signal denoising approaches have achieved impressive performance compared with traditional ones. It is well known that the characteristics of self-similarity (including non-local and local ones) of data (e.g., natural images and time-domain signals) are widely leveraged for denoising. However, existing deep learning-based EEG signal denoising methods ignore either the non-local self-similarity (e.g., 1-D convolutional neural network) or local one (e.g., fully connected network and recurrent neural network). To address this issue, we propose a novel 1-D EEG signal denoising network with 2-D transformer, namely EEGDnet. Specifically, we comprehensively take into account the non-local and local self-similarity of EEG signal through the transformer module. By fusing non-local self-similarity in self-attention blocks and local self-similarity in feed forward blocks, the negative impact caused by noises and outliers can be reduced significantly. Extensive experiments show that, compared with other state-of-the-art models, EEGDnet achieves much better performance in terms of both quantitative and qualitative metrics. Specifically, EEGDnet can achieve 18% and 11% improvements in correlation coefficients when removing ocular artifacts and muscle artifacts, respectively.

BS-80K: The first large open-access dataset of bone scan images

BACKGROUND

Radionuclide bone scanning is one of the most common tools in the inspection of bone metastasis. Conventionally, the analysis of bone scan image is derived from manual diagnosing. However, this task requires extensive subjective diagnostic experience and is extremely time-consuming. To this end, a series of studies concerning computer-aided diagnosis via machine learning tools have been proposed. Although some inspiring progress has been achieved, the implemented bone scan image datasets in these research areas are generally too small, private or non-general, which limits their practical significance and impedes the follow-up research.

METHOD

To address this issue, we present a large, publicly available and general dataset consisting of 82544 bone scan images associated with 3247 patients from West China Hospital, named BS-80K. In BS-80K, each patient provides two whole bone scan images corresponding to the anterior view (ANT) and the posterior view (POST). For each view, there are 13 region-wise slices of the body parts susceptible to bone metastasis. Based on an authorized original labeling criterion, labels annotated by experienced specialists are offered with the images. Moreover, within each whole body image, multiple bounding boxes containing suspectable hot spots and their annotations are supplied as well. All images in BS-80K have been de-identified to protect patients' privacy.

RESULTS

Based on 6 popular deep learning models for classification and object detection, we provide the benchmark for a number of computer-aided medical tasks, including general bone metastasis prediction and object detection for whole body images, and specific bone metastasis prediction for different body parts. According to extensive experiments, the adopted classification models achieve remarkable results in accuracy and specificity (around 95%) on most metastasis prediction tasks, which are approximate to the average ability of corresponding specialists. As for the object detection task, the best average precision of the adopted models reaches 0.2484 and the lowest is 0.1334.

DISCUSSION

Through the comparison of metastasis prediction performance between the benchmark and related work, we observe that the widely used models trained by BS-80K achieve significantly better results than the elaborately designed models trained by smaller datasets. This indicates that with the large amount of data, BS-80K has great potential to galvanize the research about computer-aided analysis on bone scan image.

CONCLUSION

To the best of our knowledge, BS-80K is the first large publicly available dataset of bone scanning, which favors a wide range of research on computer-aided bone metastasis diagnosis. The full dataset is now available at https://drive.google.com/drive/folders/1DOBkLXgQeREQjF-nQIGNBBzPCb5s7RNu?usp=sharing.

Machine learning based early mortality prediction in the emergency department

BACKGROUND

It is a great challenge for emergency physicians to early detect the patient's deterioration and prevent unexpected death through a large amount of clinical data, which requires sufficient experience and keen insight.

OBJECTIVE

To evaluate the performance of machine learning models in quantifying the severity of emergency department (ED) patients and identifying high-risk patients.

METHODS

Using routinely-available demographics, vital signs and laboratory tests extracted from electronic health records (EHRs), a framework based on machine learning and feature engineering was proposed for mortality prediction. Patients who had one complete record of vital signs and laboratory tests in ED were included. The following patients were excluded: pediatric patients aged < 18 years, pregnant woman, and patients died or were discharged or hospitalized within 12 h after admission. Based on 76 original features extracted, 9 machine learning models were adopted to validate our proposed framework. Their optimal hyper-parameters were fine-tuned using the grid search method. The prediction results were evaluated on performance metrics (i.e., accuracy, area under the curve (AUC), recall and precision) with repeated 5-fold cross-validation (CV). The time window from patient admission to the prediction was analyzed at 12 h, 24 h, 48 h, and entire stay.

RESULTS

We studied a total of 1114 ED patients with 71.54% (797/1114) survival and 28.46% (317/1114) death in the hospital. The results revealed a more complete time window leads to better prediction performance. Using the entire stay records, the LightGBM model with refined feature engineering demonstrated high discrimination and achieved 93.6% (±0.008) accuracy, 97.6% (±0.003) AUC, 97.1% (±0.008) recall, and 94.2% (±0.006) precision, even if no diagnostic information was utilized.

CONCLUSIONS

This study quantifies the criticality of ED patients and appears to have significant potential as a clinical decision support tool in assisting physicians in their clinical routine. While the model requires validation before use elsewhere, the same methodology could be used to create a strong model for the new hospital.

Dual self-paced multi-view clustering

By utilizing the complementary information from multiple views, multi-view clustering (MVC) algorithms typically achieve much better clustering performance than conventional single-view methods. Although in this field, great progresses have been made in past few years, most existing multi-view clustering methods still suffer the following shortcomings: (1) most MVC methods are non-convex and thus are easily stuck into suboptimal local minima; (2) the effectiveness of these methods is sensitive to the existence of noises or outliers; and (3) the qualities of different features and views are usually ignored, which can also influence the clustering result. To address these issues, we propose dual self-paced multi-view clustering (DSMVC) in this paper. Specifically, DSMVC takes advantage of self-paced learning to tackle the non-convex issue. By applying a soft-weighting scheme of self-paced learning for instances, the negative impact caused by noises and outliers can be significantly reduced. Moreover, to alleviate the feature and view quality issues, we develop a novel feature selection approach in a self-paced manner and a weighting term for views. Experimental results on real-world data sets demonstrate the effectiveness of the proposed method.

Differential effects of size-specific particulate matter on lower respiratory infections in children: A multi-city time-series analysis in Sichuan, China

Evidence on the short-term effects of size-specific particulate matter with aerodynamic diameter ≤2.5 μm (PM_2.5), ≤10 μm (PM₁₀), and their difference (PM_C) on children's Lower Respiratory Infections (LRI) is scare. This study aimed to estimate the differential effects of three size-specific PM on hospitalizations of children aged <18 years for pneumonia and bronchitis in 18 cities of southwestern China. The city-specific association was firstly estimated using the over-dispersed generalized additive model and then combined to obtain the regional average association. Further, to evaluate the robustness of the key findings, subgroup analyses and co-pollutant models were constructed. PM-related risks of LRI differed by PM fractions and cause-specific LRI. A 10 μg/m³ increment in PM_2.5_lag03, PM₁₀_lag06, and PM_C_lag06 was associated with a 0.79% (95% CI: 0.29%, 1.29%), 0.77% (95% CI: 0.13%, 1.41%), and 2.33% (95% CI: 1.23%, 3.44%) increase in children's LRI hospitalizations, respectively. After adjustment for gaseous pollutants, adverse effects of the three types of size-specific PM on pneumonia hospitalizations were stable, ranging from 0.29% (95% CI: 0.05%, 0.54%) for PM_2.5-2.50% (95% CI: 1.38%, 3.64%) for PM_C. Additionally, PM_C-related risk of bronchitis hospitalizations remained stable after adjustment for gaseous pollutants. Associations of pneumonia with PM_C and PM₁₀ in infants, bronchitis with PM_2.5 in children aged 6-17 years, pneumonia and bronchitis with PM_2.5, PM_C, and PM₁₀ in children aged 1-5 years were all statistical significant. Specifically, the effects of PM_2.5 on LRI hospitalizations increased by age, with the highest effect of 1.72% (95%CI: 1.01%, 2.43%) in children aged 6-17 years. Our study provided evidence for short-term effects of different PM fractions on children LRI hospitalizations in Southwestern China, which will be useful for making and promoting policies on air quality standards in order to protect children's health.

Targeted and Combined TPCA-1-Gold Nanocage Therapy for In Vivo Treatment of Inflammatory Arthritis

Rheumatoid arthritis (RA) is an autoimmune disease that is currently incurable. Inhibition of inflammation can prevent the deterioration of RA. 2-[(Aminocarbonyl)amino]-5-(4-fluorophenyl)-3-thiophenecarboxamide (TPCA-1) suppresses inflammation via the inhibition of nuclear factor-κ (NF-κB) signaling pathway. Gold-based therapies have been used to treat inflammatory arthritis since the 1940s. Hyaluronic acid (HA) is a targeting ligand for CD44 receptors overexpressed on activated macrophages. Therefore, a combined therapy based on TPCA-1, gold, and HA was explored for the treatment of RA in this study. We used gold nanocages (AuNCs) to load TPCA-1 and modified the TPCA-1 (T) loaded AuNCs with HA and peptides (P) to construct an anti-inflammatory nanoparticle (HA-AuNCs/T/P). An adjuvant-induced arthritis (AIA) mice model was used to investigate the in vivo anti-inflammatory efficacy of HA-AuNCs/T/P. In vivo distribution results showed that HA-AuNCs/T/P had increased and prolonged accumulation at the inflamed paws of AIA mice. Treatment by the HA-AuNCs/T/P suppressed joint swelling and alleviated cartilage and bone damage. By loading to HA-AuNCs/T/P, the effective concentration of TPCA-1 was greatly reduced from 20 to 0.016 mg/kg mice. This study demonstrated that HA-AuNCs/T/P could effectively suppress inflammation and alleviate the symptoms of AIA mice, suggesting a great potential of HA-AuNCs/T/P for the treatment of RA.

[Current situation of screening, prevention and treatment of bleeding esophageal varices in cirrhotic portal hypertension in Tibet region: a multicenter study]

Objective: To investigate and analyze the current situation, screening, clinical characteristics, prevention and treatment of bleeding esophageal varices in cirrhotic patients with portal hypertension in Tibet region. Methods: Clinical data of cirrhotic patients with portal hypertension through March 2017 to February 2020 from Tibet region were collected and analyzed retrospectively. Results: 511 cases with liver cirrhosis were included in the study, of which 185 cases (36.20%) had compensated cirrhosis and 326 cases (63.80%) had decompensated cirrhosis. Further analysis of the etiological data of liver cirrhosis showed that 306 cases (59.88%) were of chronic hepatitis B, 113 cases (22.11%) of alcoholic liver disease, and 68 cases (13.31%) of chronic hepatitis B combined with alcoholic liver disease. Among patients with compensated liver cirrhosis, 48 cases (25.95%) underwent endoscopic examination of which 33 diagnosed as high-risk variceal bleeding. However, none of these 33 cases had received non-selective β-blocker therapy, and only four patients had received endoscopic variceal banding therapy. Among patients with decompensated liver cirrhosis, 83 cases (25.46%) had a history of upper gastrointestinal bleeding, 297 cases (91.10%) had ascites, 23 cases (7.05%) had hepatic encephalopathy, and 3 cases (0.92%) had hepatorenal syndrome. Among the patients with a history of upper gastrointestinal bleeding, 42 cases (50.60%) had received secondary preventive treatment for bleeding esophageal varices, including 39 cases of endoscopic treatment, 1 case of endoscopic combined drug treatment, 3 cases of interventional treatment, and 2 cases of surgical treatment. Conclusion: Chronic hepatitis B and alcoholic liver diseases are the main causes of liver cirrhosis in Tibet region. Moreover, this region lacks screening, prevention and treatment for bleeding esophageal varices in cirrhotic patients with portal hypertension. Therefore, it is necessary to increase the screening of high-risk groups to prevent and improve the first-time bleeding, and promote multidisciplinary team to prevent and treat re-bleeding.

Synergistic Treatment of Tumor by Targeted Biotherapy and Chemotherapy via Site-Specific Anchoring of Aptamers on DNA Nanotubes

BACKGROUND

Aptamers have been widely used as targeted therapeutic agents due to its relatively small physical size, flexible structure, high specificity, and selectivity. Aptamers functionalized nanomaterials, not only enhance the targeting of nanomaterials, but can also improve the stability of the aptamers. We developed aptamer C2NP (Apt) conjugated straight DNA nanotubes (S-DNT-Apt) and twisted DNA nanotubes (T-DNT-Apt) as nanocarriers for doxorubicin (DOX).

METHODS

The twisted DNA nanotubes (T-DNT) and straight DNA nanotubes (S-DNT) were assembled with a scaffold and hundreds of staples. Apt was site-specifically anchored on DNA nanotubes with either different spatial distribution (3 or 6 nm) or varied stoichiometry (15Apt or 30Apt). The developed nanocarriers were characterized with agarose gel electrophoresis and transmission electron microscopy. The drug loading and release in vitro were evaluated by measuring the fluorescence intensity of DOX using a microplate reader. The stability of DNT in cell culture medium plus 10% of FBS was evaluated by agarose gel electrophoresis. The cytotoxicity of DNA nanostructures against K299 cells was tested with a standard CCK8 method. Cellular uptake, cell apoptosis, cell cycle and reactive oxygen species level were investigated by flow cytometry. The expression of p53 was examined by Western Blot.

RESULTS

T-DNT-30Apt-6 exhibited the highest cytotoxicity when the concentration of Apt was 120 nM. After intercalation of DOX, the cytotoxicity of DOX@T-DNT-30Apt-6 was further enhanced due to the combination of chemotherapy of DOX and biotherapy of Apt. The enhanced cytotoxicity of DOX@T-DNT-30Apt-6 can be explained by the increase in the cellular uptake, cell apoptosis and intracellular ROS levels. Additionally, the interaction between Apt and its receptor CD30 could upregulate the expression of p53.

CONCLUSION

These results demonstrate that both stoichiometry and spatial arrangement of Apt on T-DNT-Apt influence the anticancer activity. The developed twisted DNA nanotubes may be a solution for the synergistic treatment of cancer.

Recovery of stem cell proliferation by low intensity vibration under simulated microgravity requires LINC complex

Mesenchymal stem cells (MSC) rely on their ability to integrate physical and spatial signals at load bearing sites to replace and renew musculoskeletal tissues. Designed to mimic unloading experienced during spaceflight, preclinical unloading and simulated microgravity models show that alteration of gravitational loading limits proliferative activity of stem cells. Emerging evidence indicates that this loss of proliferation may be linked to loss of cellular cytoskeleton and contractility. Low intensity vibration (LIV) is an exercise mimetic that promotes proliferation and differentiation of MSCs by enhancing cell structure. Here, we asked whether application of LIV could restore the reduced proliferative capacity seen in MSCs that are subjected to simulated microgravity. We found that simulated microgravity (sMG) decreased cell proliferation and simultaneously compromised cell structure. These changes included increased nuclear height, disorganized apical F-actin structure, reduced expression, and protein levels of nuclear lamina elements LaminA/C LaminB1 as well as linker of nucleoskeleton and cytoskeleton (LINC) complex elements Sun-2 and Nesprin-2. Application of LIV restored cell proliferation and nuclear proteins LaminA/C and Sun-2. An intact LINC function was required for LIV effect; disabling LINC functionality via co-depletion of Sun-1, and Sun-2 prevented rescue of cell proliferation by LIV. Our findings show that sMG alters nuclear structure and leads to decreased cell proliferation, but does not diminish LINC complex mediated mechanosensitivity, suggesting LIV as a potential candidate to combat sMG-induced proliferation loss.

Attributable risk of hospital admissions for overall and specific mental disorders due to particulate matter pollution: A time-series study in Chengdu, China

The associations of particulate matter (PM) pollution with the morbidity of overall and subtypes of mental disorders (MDs), as well as the corresponding morbidity burden, remain understudied, especially in developing countries. This study aimed to evaluate the short-term effects of PM_2.5 (diameters ≤ 2.5 µm), PM₁₀ (diameters ≤ 10 µm) and PM_C (diameters between 2.5 and 10 µm) on hospital admissions (HAs) for MDs in Chengdu, China, during 2015-2016, and calculate corresponding attributable risks. A generalized additive model (GAM) with controlling for time trend, meteorological conditions, holidays and day of the week was used to estimate the associations. Stratified analyses were also performed by age, gender and season. We further estimated the burden of HAs for MDs attributable to PM exposure. During the study period, a total of 10,947 HAs for MDs were collected. PM_2.5, PM₁₀ and PM_C were significantly associated with elevated risks of MDs hospitalizations. Each 10 μg/m³ increase in PM_2.5, PM₁₀ and PM_C at lag06 corresponded to an increase of 2.89% (95% CI: 0.75-5.08%), 1.91% (95% CI: 0.57-3.28%) and 3.95% (95% CI: 0.84-7.15%) in daily HAs for MDs, respectively. The risk estimates of PM on MDs hospitalizations were generally robust after adjustment for gaseous pollutants in two-pollutant models. We found stronger associations between PM pollution and MDs in males and in cool seasons than in females and in warm seasons. For specific subtypes of MDs, significant associations of PM pollution with dementia,schizophrenia and depression were observed. Using WHO's air quality guidelines as the reference concentrations, 9.53% (95% CI: 2.67-15.58%), 9.17% (95% CI: 2.91-14.70%) and 6.10% (95% CI: 1.40-10.32%) of HAs for MDs could be attributable to PM_2.5, PM₁₀ and PM_C, respectively. Our results suggested that PM exposure might be an important trigger of hospitalizations for MDs in Chengdu, China, and account for substantial morbidity burden.

Attributable risk of hospital admissions for overall and specific mental disorders due to particulate matter pollution: A time-series study in Chengdu, China

The associations of particulate matter (PM) pollution with the morbidity of overall and subtypes of mental disorders (MDs), as well as the corresponding morbidity burden, remain understudied, especially in developing countries. This study aimed to evaluate the short-term effects of PM_2.5 (diameters ≤ 2.5 µm), PM₁₀ (diameters ≤ 10 µm) and PM_C (diameters between 2.5 and 10 µm) on hospital admissions (HAs) for MDs in Chengdu, China, during 2015-2016, and calculate corresponding attributable risks. A generalized additive model (GAM) with controlling for time trend, meteorological conditions, holidays and day of the week was used to estimate the associations. Stratified analyses were also performed by age, gender and season. We further estimated the burden of HAs for MDs attributable to PM exposure. During the study period, a total of 10,947 HAs for MDs were collected. PM_2.5, PM₁₀ and PM_C were significantly associated with elevated risks of MDs hospitalizations. Each 10 μg/m³ increase in PM_2.5, PM₁₀ and PM_C at lag06 corresponded to an increase of 2.89% (95% CI: 0.75-5.08%), 1.91% (95% CI: 0.57-3.28%) and 3.95% (95% CI: 0.84-7.15%) in daily HAs for MDs, respectively. The risk estimates of PM on MDs hospitalizations were generally robust after adjustment for gaseous pollutants in two-pollutant models. We found stronger associations between PM pollution and MDs in males and in cool seasons than in females and in warm seasons. For specific subtypes of MDs, significant associations of PM pollution with dementia,schizophrenia and depression were observed. Using WHO's air quality guidelines as the reference concentrations, 9.53% (95% CI: 2.67-15.58%), 9.17% (95% CI: 2.91-14.70%) and 6.10% (95% CI: 1.40-10.32%) of HAs for MDs could be attributable to PM_2.5, PM₁₀ and PM_C, respectively. Our results suggested that PM exposure might be an important trigger of hospitalizations for MDs in Chengdu, China, and account for substantial morbidity burden.

[Brain derived neurotrophic factor enhances the role of mesenchymal stem cells in inhibiting follicular helper T cells]

目的

探讨脑源性神经营养因子（BDNF）增强间充质干细胞（MSC）抑制滤泡辅助性T细胞（Tfh细胞）的作用及机制。

方法

ELISA法检测MSC培养上清中吲哚胺2,3-二加氧酶（IDO）、IL-10、TGF-β和IL-21的含量；采集健康志愿者的外周血标本，采用人淋巴细胞分离液分离外周血中的淋巴细胞；采用Transwell小室进行MSC和淋巴细胞共培养，流式细胞术检测CD4⁺CXCR5⁺ Tfh细胞及其亚群的比例。

结果

①BDNF组（BDNF刺激的MSC）培养上清IL-10、TGF-β、IDO浓度均高于对照组（加入等体积磷酸盐缓冲液）[IL-10：（42.1±4.4）ng/ml对（19.3±2.1）ng/ml，t=4.761，P=0.009；TGF-β：（13.9±1.7）ng/ml对（5.3±0.6）ng/ml，t=5.129，P=0.008；IDO：（441.3±56.9）ng/ml对（226.7±37.6）ng/ml，t=3.130，P=0.035]；②BDNF组（淋巴细胞与BDNF刺激的MSC共培养）与MSC组（淋巴细胞与MSC共培养）比较：CD4⁺CXCR5⁺Tfh细胞比例降低[（3.37±0.21）%对（6.51±0.27）%，t=9.353，P<0.001]，CD4⁺ CXCR5⁺ CXCR3⁺ CCR6⁻Tfh1细胞比例升高[（41.14±2.04）%对（26.72±2.57）%，t=4.383，P=0.012]，CD4⁺CXCR5⁺CXCR3⁻CCR6⁻Tfh2细胞和CD4⁺CXCR5⁺CXCR3⁻CCR6⁺Tfh17细胞比例降低[Tfh2：（30.16±5.38）%对（43.26±4.11）%，t=4.426，P=0.012；Tfh17：（15.61±1.52）%对（22.32±0.72）%，t=4.202，P=0.014]，CD4⁺CXCR5⁺Foxp3⁺ Tfr细胞比例升高[（4.95±0.22）%对（2.32±0.16）%，t=10.241，P<0.001]，淋巴细胞培养上清中IL-21浓度降低[（0.28±0.03）ng/ml对（0.85±0.08）ng/ml，t=6.675，P=0.003]。

结论

BDNF能够增强MSC抑制Tfh细胞的作用，机制是抑制淋巴细胞中Tfh细胞比例升高及其向Tfh2和Tfh17亚群的分化。

The burden of overall and cause-specific respiratory morbidity due to ambient air pollution in Sichuan Basin, China: A multi-city time-series analysis

Few studies have investigated the respiratory morbidity burden due to ambient air pollution in China, especially in a multi-city setting. This study aimed to estimate the short-term effects of ambient air pollutants (PM₁₀, PM_2.5, NO₂ and SO₂) on hospital admissions (HAs) for overall and cause-specific respiratory diseases, as well as the associated burden in 17 cities of Sichuan Basin, China during 2015-2016. Firstly, city-specific effect estimates for each pollutant on respiratory HAs were obtained using generalized additive model with quasi-Poisson link, and then random- or fixed-effects meta-analysis was applied to pool the effect estimates at the regional level. Subgroup analyses by sex, age, season and region were also performed. A total of 757,712 respiratory HAs were collected from all the tertiary and secondary hospitals located in the 17 cities. Risks of HAs for overall and cause-specific respiratory diseases were elevated following increased PM₁₀, PM_2.5, NO₂ and SO₂ exposure. An increase of 10 μg/m³ in PM₁₀ at lag01, PM_2.5 at lag01, NO₂ at lag0 and SO₂ at lag02 was associated with a 0.43% (95% CI: 0.33%, 0.53%), 0.53% (95% CI: 0.39%, 0.68%), 2.36% (95% CI: 1.75%, 2.98%) and 2.54% (95% CI: 1.51%, 3.59%) increases in total respiratory HAs, respectively. Children (≤ 14 years) and elderly (≥ 65 years) appeared to be more vulnerable to the effects of ambient air pollutants. Comparing to the WHO's air quality guidelines, we estimated that 1.84% (95%CI: 1.42%, 2.25%), 1.73% (95%CI: 1.27%, 2.19%) and 0.34% (95%CI: 0.21%, 0.48%) of respiratory HAs were due to PM₁₀, PM_2.5 and SO₂ exposure, respectively. This study suggests that air pollution might be an important trigger of respiratory admissions, and result in substantial burden of HAs for respiratory diseases in Sichuan Basin.

Training-Based Gradient LBP Feature Models for Multiresolution Texture Classification

Local binary pattern (LBP) is a simple, yet efficient coding model for extracting texture features. To improve texture classification, this paper designs a median sampling regulation, defines a group of gradient LBP (gLBP) descriptors, proposes a training-based feature model mapping method, and then develops a texture classification frame using the multiresolution feature fusion of four gLBP descriptors. Cooperated by median sampling, four descriptors encode a pixel respectively by central gradient, radial gradient, magnitude gradient and tangent gradient to generate initial gLBP patterns. The feature mapping models of gLBP descriptors are constructed by the maximal relative-variation rate (mr2) of rotation-invariant patterns, and then prestored as mapping lookup files. By mapping, initial patterns can be transformed into low-dimensional ones. And then it generates multiresolution texture features via the joint and concatenation of gLBP descriptors on different sampling parameters. A trained nearest neighbor classifier with chi-square distance is applied to classify textures by feature histograms. The experimental results of simulation on five public texture databases show that the proposed method is reliable and efficient in texture classification. In comparison with nine other similar approaches, including two state-of-the-art ones, the proposed method runs faster than most of them and also outperforms all of them in terms of classification accuracy and noise robustness. It achieves higher accuracy and has also better robustness to the Salt&Pepper and Gaussian noise added artificially into texture images.

[Effect of emergency thoracic endovascular aortic repair in patients with acute traumatic thoracic aortic injury]

Objective: To investigate the effect of emergency thoracic endovascular aortic repair (TEVAR) in patients with acute traumatic thoracic aortic injury. Method: From January 2014 to December 2016, a total of 35 patients with acute traumatic thoracic aortic injuries were treated with emergency TEVAR in our hospital, their clinical data were analyzed retrospectively in this study. Results: The patients were 42 (34, 55) years old,and there were 31 males.All cases were diagnosed by emergency aorta computed tomography angiography (CTA),and 5 cases were diagnosed as aortic transaction, 13 cases were diagnosed as aortic pseudoaneurysm, 7 cases were diagnosed as aortic dissection, and 10 cases were diagnosed as aortic intramural hematoma combined hemothorax.The concomitant injuries included cerebral contusion (3 cases, 8.6%), pulmonary contusion with rib fracture (31 cases, 88.5%), long bone fracture (7 cases, 22.5%), contusion of viscera or internal organs (3 cases, 8.6%).Emergency TEVAR were performed with vascular suture system preset under local anesthesia after diagnosis,and combined injury was treated in related departments.CTA was repeated after 1, 3 and 6 months and yearly thereafter. One patient died before transferring to catheter room,and 34 (97.1%) patients underwent TEVAR procedure successfully.Time from door to operating room was (88.6±26.6) minutes,and the procedure time was (52.0±9.4) minutes. A total of 69 Perclose Proglide vascular suture system were used,and 2 cases underwent surgical suture because of hematoma and pseudoaneurysm formation in femoral arteries.The involved length of thoracic aorta was (44.5±7.4)mm. A total of 46 stent-grafts were implanted, the length of stent-graft was (164.3±15.2)mm,and the proximal oversize rate was (22.3±8.6)%. The follow-up time was 24 (12,24) months, and there were no procedure related complication such as endoleak and paraplegia. Complete aortic remodeling was observed in 14 cases. Fully thrombolization at stent segments were observed in 7 cases. Fully thrombalization of pseudoaneurysms were observed in 13 cases. One patient complained mild left upper limb weakness due to left subclavian artery occlusion. Conclusion: Emergency TEVAR is safe and effective procedure for the treatment of patients with acute traumatic thoracic aortic injury.

Immunoproteomics to identify Staphylococcus aureus antigens expressed in bovine milk during mastitis

Staphylococcus aureus is an opportunistic pathogen affecting both human and animal species. An effective vaccine to prevent S. aureus bovine disease and transmission would have positive effects on animal well-being, food production, and human health. The objective of this study was to identify multiple antigens that are immunoreactive during udder colonization and disease for exploration as vaccine antigens to prevent bovine mastitis. Staphylococcus aureus produces several cell wall-anchored and surface-associated virulence factors that play key roles in the pathogenesis of mastitis. Many of these proteins are conserved between different strains of S. aureus and represent promising vaccine candidates. We used an immunoproteomics approach to identify antigenic proteins from the surface of S. aureus. The expression of cell wall and surface proteins from S. aureus was induced under low iron conditions, followed by trypsin extraction and separation by 2-dimensional electrophoresis. The separated proteins were blotted with antibodies from mastitic bovine milk and identified by liquid chromatography-mass spectrometry. Thirty-eight unique proteins were identified, of which 8 were predicted to be surface exposed and involved in S. aureus virulence. Two surface proteins, iron-regulated surface determinant protein C (IsdC) and ESAT-6 secretion system extracellular protein (EsxA), were cloned, expressed, and purified from Escherichia coli for confirmation of immune reactivity by ELISA. A PCR of 37 bovine S. aureus isolates indicated that the presence of esxA and isdC is conserved, and amino acid alignments revealed that IsdC and EsxA sequences are highly conserved. The immunoproteomics technique used in this study generated reproducible results and identified surface exposed and reactive antigens for further characterization.

[Feasibility and efficacy of transcatheter closure of anastomotic leakage after aortic surgery using Amplatzer Vascular Plug Ⅲ]

Objective: To investigate the feasibility and efficacy of transcatheter closure of anastomotic leakage after aortic surgery using Amplatzer Vascular Plug Ⅲ (AVP Ⅲ). Methods: A retrospective analysis was performed in 5 patients with anastomotic leakage after aortic surgery, who underwent transcatheter closure in our hospital from January to June 2017 using AVP Ⅲ. Surgeries were performed in 3 cases of Standford type A dissection, 1 case of ascending aortic aneurysm and 1 case of persistent truncus.There were 3 males,and age was (43.8±13.1) years old. Anastomotic leakages located at the ascending aorta in 4 patients, and the other one located between the aortic arch and the stent-graft.Three of them had aorta-right atrium fistula and patients suffered from progressive heart failure. False aneurysm between aorta and pulmonary artery was formed in 1 patient, and patent aortic false lumenwas found in the other patient. All the AVP Ⅲ were deployed based on a femoral arteriosus loop. Patients were followed up after transcatheter closure to observe the clinical results. Results: Six AVP Ⅲ were successfully implanted in the 5 patients. Trivial residual shunt was seen in 1 patient after closure. The patients were followed up 6 (1, 6) months. The cardiac function improved from NYHA class Ⅱ-Ⅳ to class Ⅰ-Ⅱ after the procedure in 3 congestive heart failure patients.The right atrium systolic pressure was significantly reduced after the procedure((8.7±1.8) mmHg (1 mmHg=0.133 kPa) vs. (24.3±2.3) mmHg, P=0.03). The diameter of the false aneurysm reduced in 1 patient after the procedure. Complete thrombosis formation of the thoracic false lumen was observed in 1 patient. Conclusion: Transcatheter closure of anastomotic leakage after aortic surgery using AVP Ⅲ is feasible and effective according to our primary experience.

CCAAT enhancer binding protein β promotes tumor growth and inhibits apoptosis in prostate cancer by methylating estrogen receptor β

The CCAAT enhancer binding protein β (C/EBPβ) is overexpressed at late stages in carcinogenesis of prostate cancer (PCa), suggesting that it could potentially contribute to progression of PCa. Estrogen receptor beta (ERβ) is a tumor suppressor gene in PCa. However, whether C/EBPβ could regulate ERβ by promoter methylation is still poorly understood.In this study, expression levels of C/EBPβ and ERβ in two PC lines (LNCap and PC-3), prostatic epithelial cell line (RWPE-1), forty-eight paired non-cancerous and cancerous peripheral blood samples were examined via qRT-PCR, western blotting and methylation-specific PCR. In addition, PCa cell line was infected with pCDH-C/EBPβ and pLKO.1-C/EBPβ and expression levels of C/EBPβ, ERβ and DNA methyltransferases were detected. Finally, the role of C/EBPβ in proliferation and apoptosis of PCa cell lines was examined by MTT and flow cytometer assay. Our results show a higher frequency of promoter methylation of ERβ levels in blood samples from PCa patients (16 of 48 cases) compared with that from healthy controls (3 of 48). Besides, elevated expression levels of C/EBPβ were found in PCa patients and two PCa lines (LNCap and PC-3) compared to non-cancerous cases or prostatic epithelial cell line (RWPE-1), while opposite expression levels of ERβ were found. Overexpression of C/EBPβ could regulate ERβ expression, DNA methyltransferases expression, cell proliferation and apoptosis. Our results support the conclusion that C/EBPβ down-regulated ERβ expression through increasing its promoter methylation, and then regulated proliferation and apoptosis in PCa.

Enhanced surface ozone during the heat wave of 2013 in Yangtze River Delta region, China

Under the background of global warming, occurrence of heat waves has increased in most part of Europe, Asia and Australia along with enhanced ozone level. In this paper, observational air temperature and surface ozone in the Yangtze River Delta (YRD) region of China during summer of 2013, and the regional chemistry-climate model (RegCM-CHEM4) were applied to explore the relationship between heat wave and elevated ground-level ozone. Observations indicated that YRD experienced severe heat waves with maximum temperature up to 41.1°C, 6.1°C higher than the definition of heat wave in China, and can last for as long as 27days. Maximum ozone reached 160.5ppb, exceeding the national air quality standard (secondary level) as 74.7ppb. Moreover, ozone was found to increase at a rate of 4-5ppbK^-1 within the temperature range of 28-38°C, but decrease by a rate of -1.3~-1.7ppbK^-1 under extremely high temperature. A typical heat wave case (HW: 24/7-31/7) and non-heat wave case (NHW: 5/6-12/6) were selected to investigate the mechanism between heavy ozone and heat waves. It was found that chemical reactions play the most important role in ozone formation during HW days, which result in 12ppb ozone enhancement compared to NHW days. Chemical formation of ozone can be influenced by several factors. During heat waves, a more stagnant condition, controlled by anti-cyclone with sink airflow, led to less water vapor in YRD from south and contributed to less cloud cover, which favored a strong solar radiation environment and ozone significantly increasing. High temperature also slightly promote the effect of vertical turbulence and horizontal advection, which beneficial to ozone remove, but the magnitude is much smaller than chemical effect. Our study suggests that the chemical reaction will potentially lead to substantial elevated ozone in a warmer climate, which should be taken into account in future ozone related issues.

Inflammation-related genetic variants predict toxicity following definitive radiotherapy for lung cancer

Definitive radiotherapy improves locoregional control and survival in inoperable non-small cell lung cancer (NSCLC) patients. However, radiation-induced toxicities (pneumonitis/esophagitis) are common dose-limiting inflammatory conditions. We therefore conducted a pathway-based analysis to identify inflammation-related SNPs associated with radiation-induced pneumonitis or esophagitis. 11,930 SNPs were genotyped in 201 stage I-III NSCLC patients treated with definitive radiotherapy. Validation was performed in an additional 220 NSCLC cases. After validation, 19 SNPs remained significant. A polygenic risk score (PRS) was generated to summarize the effect from validated SNPs. Significant improvements in discriminative ability were observed by adding the PRS into the clinical/epidemiological variable-based model. We then used 277 lymphoblastoid cell-lines to assess radiation sensitivity and eQTL relationships of the identified SNPs. Three genes (PRKCE,DDX58 and TNFSF7) were associated with radiation sensitivity. We concluded that inflammation-related genetic variants could contribute to the development of radiation-induced toxicities. These loci could assist in predicting those unfavorable events.

An auto-perfusing umbilical cord blood collection instrument

In this paper, the development of an automated umbilical cord blood (UCB) collection instrument, comprising of mechanical, electronics and control components, is provided in detail. UCB from the placenta provides a rich source of highly proliferative cells for many clinical uses as it contains rich Hematopoietic Stem Cells (HSCs) which yield many benefits over traditional sources such as the bone marrow and periphery blood. Current collection of UCB uses a syringe to extract blood from placenta, which is highly limited in volume and cell numbers. This paper will present the development of an automated UCB collection instrument to yield improved performance which comprised four subsystems. First, a placenta handling system is designed to produce air pressure which can realize the emulation of the uterus compression on the placenta. Second, an auto-medium injector system is presented to enable perfusion automatically. Third, a time window widening system is developed which generates vibrations during the perfusion phase and helps the exposed end of the cord cool down to a low temperature. Finally, a control platform is used to integrate all systems working together, hosting the control algorithms which operate the instrument automatically.