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Limited-angle computed tomography (CT) has arisen in some medical and industrial applications. It is also a challenging problem since some scan views are missing and the directly reconstructed images often suffer from severe distortions. For such kind of problems, we analyze the features of limited-angle CT images and propose a multi-scale dilated convolution neural network (MSD-CNN) to correct the artifacts and to restore the image. In this network, the dilated convolution layer and multi-scale pooling layer are combined to form a group and exited in the whole encoder-decoder process. Since the dilated convolutions support an exponential expansion of the receptive field without losing resolution and coverage, the obtained artifact features possess the multi-scale characteristic. Furthermore, to improve the effectiveness and accuracy of the training step, we employ a preprocessing method, which extracts image patches. Numerical experiments verify the out-performance of the proposed method compared with some conventional methods, such as Unet based deep learning,TV- and L0 -based optimization methods.

Background Diabetic nephropathy (DN) is a common complication of diabetes mellitus (DM) and also a major cause of end-stage renal disease (ESRD). Olmesartan medoxomil (OM) is an angiotensin II receptor blocker (ARB) and has been shown to exhibit renoprotective effects on a streptozotocin (STZ)-induced diabetic rat model. Yet, whether OM affects DN progression and renal injury in db/db mice, a type 2 diabetic murine model, has not been established. Methods Wild-type (n = 15) and db/db mice (n = 15) were treated with control saline or OM via oral gavage. The physiological and biochemical parameters were evaluated and histological examinations of kidney specimens were performed. Results Compared with saline-treated db/db mice, db/db mice administered with OM showed ameliorated diabetic physiological and biochemical parameters. In addition, OM decreased urinary albumin excretion and plasma creatinine level in db/db mice. Moreover, histologically, OM reduced glomerular hypertrophy and injury, and also ameliorated tubular injury, thus suggesting that OM improves renal function and minimizes renal pathological deterioration in db/db mice. Conclusion Our study reveals a beneficial role of OM in ameliorating DN in db/db mice, which is associated with its renoprotective function.

In this work, a novel, to the best of our knowledge, approach based on an x-ray thin lens imaging theory is proposed to predict the angular sensitivity responses of dual-phase-grating differential phase contrast (DPC) interferometers. Experimental validations have been performed to demonstrate the high accuracy of theoretical predictions using two different setups: one with real source images and the other with virtual source images. This new sensitivity calculation method is helpful to optimize the DPC imaging performance of a dual-phase-grating system.

Background Multiple factors, including co-exposure between lifestyle and environmental risks, are important in susceptibility to oxidative DNA damage. However, the underlying mechanism is not fully understood. This study was undertaken to evaluate whether Cytochrome P4501A1 (CYP1A1) methylation can mediate the co-exposure effect between smoking and occupational polycyclic aromatic hydrocarbons (PAH) in development of oxidative DNA damage. Methods We explored the associations between smoking and occupational PAH co-exposure effect, CYP1A1 methylation and oxidative DNA damage among 500 workers from a coke-oven plant in China. Urine biomarkers of PAH exposure (1-hydroxypyrene, 1-OHP; 2-hydroxynaphthalene, 2-NAP; 2-hydroxyfluorene, 2-FLU; and 9-hydroxyphenanthren, 9-PHE) and a marker of oxidative DNA damage (8-hydroxy- 2′- deoxyguanosine, 8-OHdG) were measured by high performance liquid chromatography. CYP1A1 methylation was measured by pyrosequencing. Finally, mediation analysis was performed to investigate whether CYP1A1 methylation mediated smoking and occupational PAH co-exposure effect on oxidative DNA damage. Results We observed significant associations of smoking and 1-OHP co-exposure with CYP1A1 hypomethylation (OR: 1.87, 95% CI: 1.01–3.47) and high 8-OHdG (OR: 2.13, 95% CI: 1.14–3.97). There was a significant relationship between CYP1A1 hypomethylation and high 8-OHdG (1st vs. 3rd tertile = 1.58, 95% CI: 1.01–2.47, P for trend = 0.046). In addition, mediation analysis suggested CYP1A1 hypomethylation could explain 13.6% of effect of high 8-OHdG related to smoking and 1-OHP co-exposure. Conclusions Our findings suggested that the co-exposure effect of smoking and occupational PAH could increase the risk of oxidative DNA damage by a mechanism partly involving CYP1A1 hypomethylation. Electronic supplementary material The online version of this article (10.1186/s12940-019-0508-0) contains supplementary material, which is available to authorized users.

Background We calculated the population pharmacokinetics of mizoribine in adult Chinese patients and compared the parameters with those of Japanese patients to determine whether there are any ethnic differences in blood concentration transition between these 2 populations. Methods The blood concentrations of mizoribine in 21 Chinese patients who were administered mizoribine after renal transplantation were measured at 304 time points. The absorption lag time, absorption rate constant, apparent distribution volume, and oral clearance were thereafter calculated and compared with the respective Japanese references. Results The absorption lag time, absorption rate constant, and apparent distribution volume calculated in this study were, respectively, 0.353 hour, 0.856 hour−1, and 0.776 L/kg. The oral clearance was calculated as 2.18 times the creatinine clearance using creatinine clearance as a function. The absorption rate constant, apparent distribution volume, and oral clearance are determinants of the maximum blood concentration, trough, and area under the blood concentration time curve. The relative absorption rate constant, apparent distribution volume, and oral clearance were 0.9-, 0.9-, and 1.2-fold, respectively, in Chinese patients compared with those in Japanese patients. These values are within the confidence limit, suggesting that there is no significant PK difference between the 2 ethnic groups. Conclusions Results of this study showed no ethnic difference in blood mizoribine concentration transition between Chinese and Japanese patients. In addition, the population pharmacokinetic parameters obtained in this study are useful in determining the initial dosage or in the Bayesian analysis of mizoribine concentrations using scarce time points.

The aim of the study was to investigate the effect of immunosuppression therapy early after kidney transplantation, particularly exposure of mycophenolic acid (MPA) and calcineurin inhibitor (CNI), on posttransplantation de novo HLA antibody production. Methods A single-center retrospective cohort study was performed at the First Affiliated Hospital of Sun Yat-sen University, enrolling the kidney transplant or pancreas-kidney transplant recipients who had surgery between January 2010 and February 2016. Results A total of 214 recipients were included in the study with a median follow-up period of 1.06 years. A total of 30 recipients (14.0%) were positive in HLA antibody detection posttransplant with a median follow-up period of 1.46 years. Ten recipients (4.7%) lost their allograft function during follow-up, and 6 of them (60%) developed de novo HLA antibody after graft failure. Multivariate analysis showed that acute rejection significantly increased the risk of de novo HLA antibody (hazard ratio [HR], 2.732). Intensified MPA dosing therapy reduced the risk by 59.8% (HR, 0.402); low-dose CNI therapy increased the risk by 33.3% (HR, 1.333), and the effect of extremely low-dose CNI therapy was even larger (HR, 2.242). Conclusion The risk of de novo HLA antibody can be decreased by reducing the risk of acute rejection. A tendency was seen in low-dose CNI therapy to increase the risk of de novo HLA antibody, but intensified MPA dosing therapy may provide an umbrella protection effect by reducing the risk. Prospective study was required to confirm the effects.

Objective: The purpose of this work is to investigate the feasibility of using deep convolutional neural network (CNN) to improve the image quality of a grating-based X-ray differential phase contrast imaging (XPCI) system. Methods: In this work, a novel deep CNN based phase signal extraction and image noise suppression algorithm (named as XP-NET) is developed. The numerical phase phantom, the ex vivo biological specimen and the ACR breast phantom are evaluated via the numerical simulations and experimental studies, separately. Moreover, images are also evaluated under different low radiation levels to verify its dose reduction capability. Results: Compared with the conventional analytical method, the novel XP-NET algorithm is able to reduce the bias of large DPC signals and hence increasing the DPC signal accuracy by more than 15%. Additionally, the XP-NET is able to reduce DPC image noise by about 50% for low dose DPC imaging tasks. Conclusion: This proposed novel end-to-end supervised XP-NET has a great potential to improve the DPC signal accuracy, reduce image noise, and preserve object details. Significance: We demonstrate that the deep CNN technique provides a promising approach to improve the grating-based XPCI performance and its dose efficiency in future biomedical applications.

Objective: To observe the anxiety and depression experienced by patients with suspected and confirmed COVID-19 during hospitalization and isolation.Methods: A cross-sectional survey was performed with 66 patients with suspected and confirmed COVID-19 who were admitted to the Fifth Affiliated Hospital of Sun Yat-sen University from February 9, 2020, to February 22, 2020. The data collected including sex, age, education level, and nucleic acid test results. Anxiety, depression, and sleep disorders were evaluated using the Self-Rating Anxiety Scale (SAS), Self-Rating Depression Scale (SDS) and Pittsburgh Sleep Quality Index Scale (PSQI), respectively. Statistical analysis: SPSS 23.0 software was used for data processing, and multifactor logistic regression analysis was used to identify the independent risk factors. Spearman correlation analysis was used to study the correlations among the observed indicators; P Results: The incidences of anxiety, depression, and sleep disorders in the suspected case group were 18.2%, 18.2%, and 39.4%; the incidences of anxiety, depression, and sleep disorders in the diagnosed group were 42.4%, 57.6%, and 69.7%. The incidence of sleep disorders was higher than the domestic norm, and the difference was statistically significant (P P Conclusion: Patients with suspected and confirmed COVID-19, especially people aged 50 years and over, have significant anxiety, depression and sleep disorders. Anxiety, depression and sleep disorders in patients with confirmed cases are more serious than those in patients with suspected cases. It is necessary to focus on the psychological state of such patients, actively conduct psychological counseling, and reduce their anxiety and depression.

In this work, we developed a new theoretical framework using wave optics to explain the working mechanism of the grating based X-ray differential phase contrast imaging (XPCI) interferometer systems consist of more than one phase grating. Under the optical reversibility principle, the wave optics interpretation was simplified into the geometrical optics interpretation, in which the phase grating was treated as a thin lens. Moreover, it was derived that the period of an arrayed source, e.g., the period of a source grating, is always equal to the period of the diffraction fringe formed on the source plane. When a source grating is utilized, the theory indicated that it is better to keep the periods of the two phase gratings different to generate large period diffraction fringes. Experiments were performed to validate these theoretical findings.

Due to its ability of optical sectioning and low phototoxicity, z -stacking light-sheet microscopy has been the tool of choice for in vivo imaging of the zebrafish brain. To image the zebrafish brain with a large field of view, the thickness of the Gaussian beam inevitably becomes several times greater than the system depth of field (DOF), where the fluorescence distributions outside the DOF will also be collected, blurring the image. In this paper, we propose a 3D deblurring method, aiming to redistribute the measured intensity of each pixel in a light-sheet image to in situ voxels by 3D deconvolution. By introducing a Hessian regularization term to maintain the continuity of the neuron distribution and using a modified stripe-removal algorithm, the reconstructed z -stack images exhibit high contrast and a high signal-to-noise ratio. These performance characteristics can facilitate subsequent processing, such as 3D neuron registration, segmentation, and recognition.

Glomerulonephritis recurrence has emerged as one of the leading causes of allograft loss. We aimed to investigate the effect of living-related and deceased donation on the incidence of renal allograft glomerulonephritis and its effect on renal allograft survival.Adult renal allograft recipients with primary glomerulonephritis were enrolled. Transplantation date was from Feb 2004 to Dec 2015. Exclusion criteria included combined organ transplantation, structural abnormality, diabetic nephropathy, hypertension nephropathy, obstructive nephropathy, and primary uric acid nephropathy. The incidence of biopsy-proven allograft glomerulonephritis was compared between the living-related donor group and the deceased donor group. Graft survival was assessed with Kaplan-Meier method, and Cox proportional hazard model was used to evaluate the effect of posttransplant glomerulonephritis on graft outcome.There were 525 living-related donor kidney transplant recipients (LRKTx) and 456 deceased donor kidney transplant recipients (DDKTx) enrolled. The incidence of IgA nephropathy was 8.8% in the LRKTx group and 1.3% in the DDKTx group (P .001); the incidence of focal segmental glomerulosclerosis (FSGS) was 3.8% in the LRKTx group and 1.5% in the DDKTx group (P = .03). FSGS increased the risk of graft failure compared with non-FSGS (hazard ratio [HR], 3.703 [1.459-9.397]; P = .006). IgA nephropathy increased the risk of graft failure by over 5 times 5 years after kidney transplantation compared with non-IgA nephropathy, but it did not affect early allograft survival (HR for ≥5 years, 6.139; 95% CI, 1.766-21.345; P = .004; HR for 5 years, 0.385 [0.053-2.814]; P = .35).Higher incidence of IgA nephropathy and FSGS in renal allograft was observed in living-related donor kidney transplantation compared with deceased donor kidney transplantation. De novo or recurrent IgA nephropathy and FSGS impaired long-term renal allograft survival.

Differential phase-contrast (DPC) X-ray imaging has been performed in the Talbot-Lau configuration, in which the X-ray source was a combination of an absorption grating and a laboratory X-ray generator. We report here quantitative analysis of partial coherence effects on the X-ray Talbot-Lau interferometer. Based on the visibility of the self-image, the well-known geometry condition is reproduced. It is shown that effects of partial coherence are determined by the opening ratio of the source grating, and that the effects are independent of the Talbot order and the type of the phase grating, a condition quite different from those in a Talbot interferometer. A possible explanation is discussed from the point of view of the effective spatial coherence length. Taking into account the available X-ray flux and experimental fluctuations, we present the optimum opening ratio. Furthermore, we mention that our results can also be successfully used to discuss the properties of a multiline X-ray source.

In industrial CT, it is often required to inspect large objects using short line-detectors. To acquire the complete CT data for the scanning slice of large objects using short line-detectors, some multi-scan modes have been developed. But the existing methods reconstructing an image from the data scanned by multi-scan modes have to rebin the data into fan-beam or parallel-beam form via data interpolation. The data rebinning process not only increases great computational cost, but also degrades image resolution. In this paper, we propose a backprojection-filtration (BPF)-based reconstruction algorithm for rotation–translation (RT) multi-scan mode. An important feature of the proposed algorithm is that data rebinning process is not introduced. The simulation results have verified the validity of the proposed algorithm.

The digital campus is the use of methods and tools of information technology, campus resources, management and service process of digital campus, forming the digital environment, make the reality of campus environment with information system in time and space to be extended. This paper from the digitized campus overall scheme design were analyzed, the information in the data, process, investment and other aspects of integration of design, focusing on various types of management information system and all kinds of basic digital campus platform integration, and gives the corresponding integrated example.