Circular RNA expression profile and functional analysis of circUvrag in light-induced photoreceptor degeneration.

BACKGROUND: Circular RNAs (circRNAs) are implicated in retinal pathophysiology; however, their expression profiles and functions in photoreceptor apoptosis are largely unknown. We explored circRNA-expression profiles and circUvrag (host gene: Uvrag, ultraviolet radiation resistance associated gene) function in light-induced photoreceptor apoptosis. METHODS: Sprague-Dawley rats and 661 W photoreceptor cells were exposed to blue light to establish light-induced photoreceptor degeneration. Differentially expressed circRNAs were identified using microarrays. Potential functions of dysregulated circRNAs were analysed using Gene Ontology and Kyoto Encyclopedia of Genes and Genomes analyses. CircUvrag expression and localization were evaluated using quantitative RT-PCR and fluorescence in situ hybridization, respectively. CircUvrag overexpression and knockdown were induced using a plasmid and a small interfering RNA, respectively, and retinal function and structure were assessed using scotopic electroretinography, haematoxylin-eosin staining, and TUNEL staining. Microglial migration was assessed using IBA1 immunostaining. The apoptosis ratio of photoreceptor cells in vitro was detected using flow cytometry. RESULTS: We identified 764 differentially expressed circRNAs, which were potentially related with the development of retinal structures, including neurons, dendrites, and synapses, and might participate in nervous-system pathophysiology. Light exposure enriched circUvrag in the cytoplasm of photoreceptors in the outer nuclear layer (ONL). CircUvrag knockdown decreased photoreceptor apoptosis and microglial migration to the ONL after light exposure, preserving ONL thickness and a-wave amplitude. In vitro, circUvrag knockdown inhibited photoreceptor apoptosis, although circUvrag overexpression slightly promoted photoreceptor apoptosis. CONCLUSIONS: CircUvrag knockdown attenuated light-induced photoreceptor apoptosis, and might be a potential target in retinal degeneration.

Sall4 Guides p53-Mediated Enhancer Interference upon DNA Damage in Mouse Embryonic Stem Cells.

p53 plays a pivotal role in maintaining the genomic stability of mouse embryonic stem cells (mESCs) through transcriptionally activating and repressing target genes. However, how p53 recognizes its repressed targets remains largely unknown. Herein, we demonstrate that Sall4 negatively regulates DNA damage induced apoptosis (DIA) of mESCs through mediating p53 recruitment to enhancers of ESC-associated genes repressed by p53 from promoters of p53-activated genes. Upon DNA damage, Sall4 is transcriptionally repressed by p53 and plays an anti-apoptotic role without altering p53 activation. Moreover, Sall4 is identified as a novel p53-interacting partner. Consistently, Sall4 exerts its anti-apoptotic function in a p53-dependent manner. Intriguingly, Sall4 depletion not only promotes the transcriptional activation of several p53-regulated pro-apoptotic genes but also compromises p53-mediated repression of ESC master transcription factors in response to DNA damage. Mechanistically, Sall4 balances p53-binding affinity between p53-activated and -repressed genes through tethering p53 to ESC enhancers. In light of our study, Sall4 may contribute to tumorigenesis by antagonizing p53-mediated apoptosis.

Subclinical macular vessel density alterations in patients with juvenile systemic lupus erythematosus.

OBJECTIVE: The aim is to evaluate subclinical alterations of macular microvasculature in patients with juvenile systemic lupus erythematosus (JSLE). METHODS: This is a cross-sectional study of 29 eyes of 29 patients diagnosed with JSLE and 29 eyes of 29 healthy controls. The vessel density (VD) of the superficial capillary plexus (SCP), intermediate capillary plexus (ICP), deep capillary plexus (DCP), choriocapillaris (CC), and area of foveal avascular zone (FAZ) was measured using optical coherence tomography angiography (OCTA). A multiple linear regression analysis was performed to evaluate the effects of disease duration and activity on OCTA parameters. RESULTS: The VD of total (p = .007) and the superior (p = .014) and inferior (p = .004) quadrants in SCP was significantly lower in children with JSLE. The VD of total and all quadrants in ICP decreased (p = .015, p = .0045, p = .015, p = .033), except that of the temporal quadrant (p = .366). The total (p = .011) and superior quadrant (p<.01) DCP-VD showed a significant decrease in children with JSLE. The decrease in VD in the total (p = .003) and nasal quadrant (p = .017) of CC was also remarkable. No significant difference in the FAZ area was found between the two groups (p = .774). Multiple linear regression analyses adjusted for age, spherical equivalent, and intraocular pressure were conducted. No contributing factor to OCTA parameters was found. CONCLUSIONS: We demonstrated decreased VD in all layers of the retina and CC in patients with JSLE without ocular involvement. Early screening and close follow-up were recommended.

Association of delayed chemoradiotherapy with elevated Epstein-Barr virus DNA load and adverse clinical outcome in nasopharyngeal carcinoma treatment during the COVID-19 pandemic: a retrospective study.

BACKGROUND: To summarize the impact of radiotherapy (RT) and chemotherapy delays on patients with nasopharyngeal carcinoma (NPC) during the COVID-19 pandemic. METHODS: We retrospectively included 233 patients with stage II-IVa NPC treated with RT and chemotherapy between December 11, 2019 and March 11, 2020. The outcomes were elevation in the EBV DNA load between two adjacent cycles of chemotherapy or during RT, and 1-year disease-free survival (DFS). RESULTS: RT delay occurred in 117 (50%) patients, and chemotherapy delay occurred in 220 (94%) patients. RT delay of ≥ 6 days was associated with a higher EBV DNA elevation rate (20.4% vs. 3.6%, odds ratio [OR] = 6.93 [95% CI = 2.49-19.32], P < 0.001), and worse 1-year DFS (91.2% vs. 97.8%, HR = 3.61 [95% CI = 1.37-9.50], P = 0.006), compared with on-schedule RT or delay of < 6 days. Chemotherapy delay of ≥ 10 days was not associated with a higher EBV DNA elevation rate (12.5% vs. 6.8%, OR = 1.94 [95% CI = 0.70-5.40], P = 0.20), or worse 1-year DFS (93.8% vs. 97.1%, HR = 3.73 [95% CI = 0.86-16.14], P = 0.059), compared with delay of < 10 days. Multivariable analyses showed RT delay of ≥ 6 days remained an independent adverse factor for both EBV DNA elevation and DFS. CONCLUSION: To ensure treatment efficacy for patients with nonmetastatic NPC, initiation of RT should not be delayed by more than 6 days; the effect of chemotherapy delay requires further investigation.

Structural and functional analysis of multiple subretinal fluid blebs after successful surgery for rhegmatogenous retinal detachment.

INTRODUCTION: This retrospective study investigated the clinical characteristics of multiple subretinal fluid blebs (MSFBs) after successful surgery for rhegmatogenous retinal detachment (RRD), and explored the association between MSFB with best-corrected visual acuity (BCVA) and metamorphopsia. METHODS: The study comprised 206 patients after successful surgery for RRD, with 58 and 148 eyes undergoing, respectively, scleral buckling (SB) and pars plana vitrectomy (PPV). The clinical characteristics of MSFBs were analyzed by optical coherence tomography (OCT). The choroidal vessels in some cases were evaluated with OCT angiography. M-charts were used to determine the metamorphopsia. RESULTS: MSFBs occurred in 17 (29.3%) and 8 (5.4%) eyes given SB and PPV, respectively. MSFBs appeared 5.6 ± 5.5 weeks after surgery and required 34.9 ± 13.8 weeks to disappear. Disrupted external limiting membrane and ellipsoid zone could still be seen in 83.3% and 66.7% of the patients 12 months after surgery; these rates were significantly higher than those of patients without MSFBs (P = 0.047, 0.022, respectively). Twelve months post-surgery, BCVA and metamorphopsia scores of the patients with MSFBs were statistically comparable to those of the controls. CONCLUSIONS: MSFBs occur more commonly after SB than PPV. MSFBs may delay the recovery of the outer retina structure, but do not affect postoperative BCVA and metamorphopsia.

SHP-1 suppresses endotoxin-induced uveitis by inhibiting the TAK1/JNK pathway.

We investigated how Src-homology 2-domain phosphatase-1 (SHP-1) regulates the inflammatory response in endotoxin-induced uveitis (EIU), and the signalling pathways involved. One week after intravitreal injection of short hairpin RNA targeting SHP-1 or SHP-1 overexpression lentivirus in rats, we induced ocular inflammation with an intravitreal injection of lipopolysaccharide (LPS). We then assessed the extent of inflammation and performed full-field electroretinography. The concentrations and retinal expression of various inflammatory mediators were examined with enzyme-linked immunosorbent assays and Western blotting, respectively. SHP-1 overexpression and knockdown were induced in Müller cells to study the role of SHP-1 in the LPS-induced inflammatory response in vitro. Retinal SHP-1 expression was up-regulated by LPS. SHP-1 knockdown exacerbated LPS-induced retinal dysfunction and increased the levels of proinflammatory mediators in the retina, which was abrogated by a c-Jun N-terminal kinase (JNK) inhibitor (SP600125). SHP-1 overexpression had the opposite effects. In Müller cells, the LPS-induced inflammatory response was enhanced by SHP-1 knockdown and suppressed by SHP-1 overexpression. SHP-1 negatively regulated the activation of the transforming growth factor-ß-activated kinase-1 (TAK1)/JNK pathway, but not the nuclear factor-κB pathway. These results indicate that SHP-1 represses EIU, at least in part, by inhibiting the TAK1/JNK pathway and suggest that SHP-1 is a potential therapeutic target for uveitis.

Liquid biopsy posttreatment surveillance in endemic nasopharyngeal carcinoma: a cost-effective strategy to integrate circulating cell-free Epstein-Barr virus DNA.

BACKGROUND: The optimal posttreatment surveillance strategy for nasopharyngeal carcinoma (NPC) remains unclear. Circulating cell-free Epstein-Barr virus (cfEBV) DNA has been recognized as a promising biomarker to facilitate early detection of NPC recurrence. Therefore, we aim to determine whether integrating circulating cfEBV DNA into NPC follow-up is cost-effective. METHODS: For each stage of asymptomatic nonmetastatic NPC patients after complete remission to primary NPC treatment, we developed a Markov model to compare the cost-effectiveness of the following surveillance strategies: routine follow-up strategy, i.e., (1) routine clinical physical examination; routine imaging strategies, including (2) routine magnetic resonance imaging plus computed tomography plus bone scintigraphy (MRI + CT + BS); and (3) routine 18F-fluorodeoxyglucose positron emission tomography/computed tomography (PET/CT); cfEBV DNA-guided imaging strategies, including (4) cfEBV DNA-guided MRI + CT + BS and (5) cfEBV DNA-guided PET/CT. Clinical probabilities, utilities, and costs were derived from published studies or databases. Sensitivity analyses were performed. RESULTS: For all disease stages, cfEBV DNA-guided imaging strategies demonstrated similar survival benefits but were considerably more economical than routine imaging strategies. They only required approximately one quarter of the number of imaging studies compared with routine imaging strategies to detect one recurrence. Specifically, cfEBV DNA-guided MRI + CT + BS was most cost-effective for stage II (incremental cost-effectiveness ratio [ICER] $57,308/quality-adjusted life-year [QALY]) and stage III ($46,860/QALY) patients, while cfEBV DNA-guided PET/CT was most cost-effective for stage IV patients ($62,269/QALY). However, routine follow-up was adequate for stage I patients due to their low recurrence risk. CONCLUSIONS: The cfEBV DNA-guided imaging strategies are effective and cost-effective follow-up methods in NPC. These liquid biopsy-based strategies offer evidence-based, stage-specific surveillance modalities for clinicians and reduce disease burden for patients.

Synaptic changes and the response of microglia in a light-induced photoreceptor degeneration model.

Purpose: To explore synaptic changes and the response of microglia in a light-induced photoreceptor degeneration model. Methods: Sprague-Dawley rats were euthanized 1 h, 1 day, 3 days, 7 days, and 14 days after being exposed to intense blue light for 24 h. Hematoxylin and eosin (H&E) and terminal deoxynucleotidyl transferase dUTP nick-end labeling (TUNEL) staining were used to evaluate changes in the outer nuclear layer (ONL). Transmission electron microscopy (TEM) was applied to observe the ultrastructural changes in the synapses between the photoreceptors and second-order neurons. Western blotting was conducted to evaluate specific proteins, including postsynaptic density-95 (PSD-95), metabotropic glutamate receptor 6 (mGluR6), synapsin I, and synaptophysin. Immunofluorescence of CD11b and PKC-α or mGluR6 was used to explore the spatial relationships between microglial processes and synaptic elements. Immunoelectron microscopy of PSD-95 was performed to further confirm its engulfment of synaptic materials. Results: H&E and TUNEL staining showed that the thickness of the ONL decreased markedly, and the number of apoptotic photoreceptors peaked at day 1. TEM revealed darkened photoreceptor terminals and that ribbons of them were floating in the cytoplasm, coinciding with the downregulation of PSD-95 and mGluR6. Downstream synaptic protein synapsin I and synaptophysin exhibited upregulation in the inner plexiform layer. Activated microglia migrated to the outer retina, and their processes were found in close proximity to synapses in the outer plexiform layer under light and electron microscopy levels. Double immunostaining of CD11b and mGluR6 showed colocalization. PSD-95-immunoreactive electron-dense materials were observed inside the microglia suggesting engulfment of synaptic components. Conclusions: The study showed that there are early synaptic impairment and late compensatory changes in downstream synapses in this photic injury model. Activated microglia touched and directly engulfed synaptic materials. Microglia may play a role or a partial role in synaptic changes.

THE EVOLUTION OF ISOLATED NEOVASCULAR TUFTS ("POPCORN") IN RETINOPATHY OF PREMATURITY.

PURPOSE: To explore the natural evolution of isolated neovascular tufts ("popcorn") in retinopathy of prematurity (ROP) and its significance in the progression of acute ROP. METHODS: In this retrospective case series, 89 infants (89 eyes) in total having acute ROP were analyzed during serial retinal examinations with a RetCam III wide-angle fundus imaging system, among which 53 eyes were observed to have popcorn and 36 eyes did not. The clinical outcomes of the popcorn (+) group and the popcorn (-) group were compared. RESULTS: Popcorn was located only in Zone II, Stage 2 ROP, primarily in the temporal field (65%). It appeared at a mean postmenstrual age of (37.6 ± 1.3) weeks, disappeared at (41.0 ± 2.2) weeks, and lasted for (2.8 ± 1.1) weeks. The popcorn (+) group had a significantly higher natural regression incidence than the popcorn (-) group (P < 0.05). The laser-treated eyes in the popcorn (+) group had earlier presentations (36.4 ± 0.7 vs. 38.2 ± 1.3 weeks) and shorter existences (1.5 ± 0.5 vs. 3.2 ± 0.9 weeks) of popcorn than the regressed eyes (P < 0.01, respectively). CONCLUSION: Popcorn is generally a "benign" indicator of the regression of ROP. The early presentation (

Retinal sublayer analysis in juvenile systemic lupus erythematosus without lupus retinopathy.

INTRODUCTION: We aimed to analyze the thicknesses of the retinal sublayer and peripapillary retinal nerve fiber layer (pRNFL) in patients with juvenile systemic lupus erythematosus (JSLE) without lupus retinopathy. METHODS: Thirty-six patients with JSLE (36 eyes) and 30 control subjects (30 eyes) were included retrospectively. Demographic data, disease duration, and clinical manifestations were recorded. Optical coherence tomography was used to examine the macula and optic disc. The thicknesses of the retina, ganglion cell layer (GCL), inner plexiform layer (IPL), inner nuclear layer (INL), outer plexiform layer (OPL), outer nuclear layer (ONL), retinal pigment epithelium (RPE), and pRNFL were measured. The correlation between the thickness of retina and disease duration, erythrocyte sedimentation rate (ESR) were investigated. RESULTS: The retinal thicknesses of I3 and T3 were thinner in the JSLE group than in the control group (P = 0.019, P = 0.043, respectively). The thicknesses of the I3 and S6 sectors of the GCL decreased significantly (P = 0.013, and P = 0.022, respectively). The thickness of the S6 sector of the IPL was reduced in the JSLE group compared with the control group (P = 0.047). The JSLE group showed significant decrease in the thickness of the central sector of the ONL (P = 0.034). No statistically significant differences in INL, OPL, RPE, and pRNFL thicknesses were found. The retinal thicknesses of I3 (r = -0.386, P = 0.020) and T3 (r = -0.384, P = 0.021) presented negative associations with ESR, but had no significant correlations with disease duration. CONCLUSIONS: Retinal thinning was observed in patients with JSLE without lupus retinopathy, and this change was more pronounced in the inner layer. Key Points • Retinal thinning occurs in JSLE patients without lupus retinopathy. • Changes in retinal thicknesses are related to the ESR.

Unraveling the biological link between diabetes mellitus and prostate cancer: Insights and implications.

This article is a comprehensive study based on research on the connection between diabetes mellitus (DM) and prostate cancer (PCa). It investigates the potential role of DM as an independent risk factor for PCa, delving into the biological links, including insulin resistance and hormonal changes. The paper critically analyzes previous studies that have shown varying results and introduces mendelian randomization as a method for establishing causality. It emphasizes the importance of early DM screening and lifestyle modifications in preventing PCa, and proposes future research directions for further under-standing the DM - PCa relationship.

Assessment of different head tilt angles in volumetric modulated arc therapy for hippocampus-avoidance whole-brain radiotherapy.

Purpose: In the field of radiation therapy for brain metastases, whole-brain hippocampus-avoidance treatment is commonly employed. this study aims to examine the impact of different head tilt angles on the dose distribution in the whole-brain target area and organs at risk. It also aims to determine the head tilt angle to achieve optimal radiation therapy outcomes. Methods: CT images were collected from 8 brain metastases patients at 5 different groups of head tilt angle. The treatment plans were designed using the volumetric modulated arc therapy (VMAT) technique. The 5 groups of tilt angle were as follows: [0°,10°), [10°,20°), [20°,30°), [30°,40°), and [40°,45°]. The analysis involved assessing parameters such as the uniformity index, conformity index, average dose delivered to the target, dose coverage of the target, hot spots within the target area, maximum dose, and average dose received by organs at risk. Additionally, the study evaluated the correlation between hippocampal dose and other factors, and established linear regression models. Results: Significant differences in dosimetric results were observed between the [40°,45°] and [0°,10°) head tilt angles. The [40°,45°] angle showed significant differences compared to the [0°,10°) angle in the average dose in the target area (31.49 ± 0.29 Gy vs. 31.99 ± 0.29 Gy, p=0.016), dose uniformity (1.20 ± 0.03 vs. 1.24 ± 0.03, p=0.016), hotspots in the target area (33.64 ± 0.35 Gy vs. 34.42 ± 0.49 Gy, p=0.016), maximum hippocampal dose (10.73 ± 0.36 Gy vs. 11.66 ± 0.59 Gy, p=0.008), maximum dose in the lens (2.82 ± 1.10 Gy vs. 4.99 ± 0.16 Gy, p=0.016), and average dose in the lens (1.93 ± 0.29 Gy vs. 4.22 ± 0.26 Gy, p=0.008). There is a moderate correlation between the maximum dose in the hippocampi and the PTV length (r=0.49, p=0.001). Likewise, the mean dose in the hippocampi is significantly correlated with the hippocampi length (r=0.34, p=0.04). Conclusion: The VMAT plan with a head tilt angle of [40°,45°] met all dose constraints and demonstrated improved uniformity of the target area while reducing the dose to organs at risk. Furthermore, the linear regression models suggest that increasing the head tilt angle within the current range of [0°,45°] is likely to lead to a decrease in the average hippocampal dose.

Occurrence and transport of novel and legacy poly- and perfluoroalkyl substances in coastal rivers along the Laizhou Bay, northern China.

The pollution profiles of 25 legacy and emerging poly- and perfluoroalkyl substances (PFASs) in the estuaries along the Laizhou Bay, northern China were investigated to better understand the new structure of PFASs under international regulations and to estimate the mass loadings of PFASs in coastal rivers. About 39.87 kg/d of PFASs were discharged into the Laizhou Bay by the Xiaoqing, Mi and Zhimai Rivers. Total PFAS concentrations in the Xiaoqing River decreased notably in recent years, but were still greater than the levels in 2011. Contribution of replacement substances exhibited an increasing trend in recent years. However, the long-chain chemicals were still the larger contributors of PFASs. Perfluoromethoxypropionic acid (PFMPA) was first detected with high concentrations ranging from 165.3 to 586.3 ng/L in the Xiaoqing River. The results of this study provided baseline data for ecological risk assessment, environmental management and corresponding development of pollution treatment technology.

Association between tobacco exposure and bladder cancer recurrence: A systematic review and meta-analysis.

BACKGROUND: However, the connection between smoking and the prognosis of patients with bladder cancer remains unclear. AIM: To determine whether smoking is linked to the recurrence and progression of bladder cancer. METHODS: As of July 20, 2022, relevant English-language research was identified by searching PubMed, the Web of Science, and the Cochrane Library. We pooled the available data from the included studies using a random effects model. Subgroup analysis and sensitivity analysis were also conducted. RESULTS: A total of 12 studies were included in this meta-analysis. The combined analysis revealed that tobacco exposure was associated with a significantly greater recurrence rate than nonsmoking status [odd ratios (OR) = 1.76, 95%CI: 1.84-2.93], and the progression of bladder cancer was significantly greater in smokers than in nonsmokers (OR = 1.21, 95%CI: 1.02-1.44). Stratified analysis further revealed that current smokers were more likely to experience relapse than never-smokers were (OR = 1.85, 95%CI: 1.11-3.07). Former smokers also had a greater risk of relapse than did never-smokers (OR = 1.73, 95%CI: 1.09-2.73). Subgroup analysis indicated that non-Caucasians may be more susceptible to bladder cancer recurrence than Caucasians are (OR = 2.13, 95%CI: 1.74-2.61). CONCLUSION: This meta-analysis revealed that tobacco exposure may be a significant risk factor for both the recurrence and progression of bladder cancer.

[Effect of acupuncture on the p53 protein expression of mice with Alzheimer's disease].

OBJECTIVE: To observe the effect of acupuncture method for benefiting qi, regulating blood, supplementing the root, and cultivating the essence (BQRBSRCE) on the p53 protein expression of mice with Alzheimer's disease (AD). METHODS: SAMP8 mice were divided into the control group, the acupuncture group, and the non-acupoint group. The homologous SAMR1 control group was set up. Mice in the acupuncture group used acupuncture method for BQRBSRCE by needling at Tanzhong (RN17), Zhongwan (RN12), Qihai (RN6), and bilateral Xuehai (SP10), and bilateral Zusanli (ST36).Two fixed non-acupoints from bilateral ribs were needled in the non-acupoint group. The p53 protein expression in the cortex and hippocampus of mice was determined using Western blot. The pathological changes of neurons in the hippocampal CA1 region, the temporal lobe, and the occipital lobe were observed using HE staining. The expression of cortical p53-positive cells was detected by immunohistochemical assay. RESULTS: The p53 protein was highly expressed in the cortex of SAMP8, which was significantly down-regulated after acupuncture, showing statistical difference when compared with the SAMP8 control group (P < 0.05), but with no statistical difference when compared with the SAMR1 control group (P > 0.05). Needling at non-acupoints had no obvious effect on the p53 protein expression. There was no statistical difference in the p53 protein expression of the hippocampus (P > 0.05). CONCLUSION: Acupuncture method for BQRBSRCE could down-regulate the p53 protein expression in the brain of mice, improve the pathological state of brain cells, thus enhancing learning and memory capabilities of AD mice, improving their cognitive functions, with specificity of acupoints.

Iteratively distributed instrumental variable-based pseudo-linear information filter for angle-only tracking.

This paper presents a distributed filtering problem for three-dimensional angle-only target tracking (AOTT) in sensor (i.e., observer) networks. An instrumental variable-based pseudo-linear information filter (IVIF) is firstly derived on the basis of the designed bias-compensated pseudo-linear information filtering, with the help of summation forms of information quantities and bias compensation in a centralized fusion manner. Then, the distributed IVIF (DIVIF) is put forward by using finite-time average consensus to obtain the arithmetic means of defined information quantities and compensated bias in observer networks, which ensures that the filtering result of every observer is consistent with the centralized one. Finally, the iteratively DIVIF is proposed via gradually approaching the true values of relative distance and the corresponding angles between the target and every observer to get the filtering parameters more and more accurately, in order to achieve higher filtering precision. In addition, the computational complexity of the proposed method is also analyzed. The advantages of filtering precision of the proposed method over the existing pseudo-linear Kalman filter and its variants are demonstrated by an AOTT example in observer networks in terms of iteration steps, different levels of process noises and observer's accuracy.

CT synthesis from multi-sequence MRI using adaptive fusion network.

OBJECTIVE: To investigate a method using multi-sequence magnetic resonance imaging (MRI) to synthesize computed tomography (CT) for MRI-only radiation therapy. APPROACH: We proposed an adaptive multi-sequence fusion network (AMSF-Net) to exploit both voxel- and context-wise cross-sequence correlations from multiple MRI sequences to synthesize CT using element- and patch-wise fusions, respectively. The element- and patch-wise fusion feature spaces were combined, and the most representative features were selected for modeling. Finally, a densely connected convolutional decoder was applied to utilize the selected features to produce synthetic CT images. MAIN RESULTS: This study includes a total number of 90 patients' T1-weighted MRI, T2-weighted MRI and CT data. The AMSF-Net reduced the average mean absolute error (MAE) from 52.88-57.23 to 49.15 HU, increased the peak signal-to-noise ratio (PSNR) from 24.82-25.32 to 25.63 dB, increased the structural similarity index measure (SSIM) from 0.857-0.869 to 0.878, and increased the dice coefficient of bone from 0.886-0.896 to 0.903 compared to the other three existing multi-sequence learning models. The improvements were statistically significant according to two-tailed paired t-test. In addition, AMSF-Net reduced the intensity difference with real CT in five organs at risk, four types of normal tissue and tumor compared with the baseline models. The MAE decreases in parotid and spinal cord were over 8% and 16% with reference to the mean intensity value of the corresponding organ, respectively. Further, the qualitative evaluations confirmed that AMSF-Net exhibited superior structural image quality of synthesized bone and small organs such as the eye lens. SIGNIFICANCE: The proposed method can improve the intensity and structural image quality of synthetic CT and has potential for use in clinical applications.

Dissolved inorganic tin sources and its coupling with eco-environments in Bohai Bay.

Dissolved inorganic tin (DISn) and its spatial variation were examined in Bohai Bay seawaters to understand the DISn behavior and pollution in this area. DISn concentration gradually increased with the distance from the coast and showed a slight decrease with the increasing depth from surface water, suggesting the scavenged behavior of tin with an atmospheric input to surface water. Besides, the higher DISn values also were found near the Haihe Estuary inferring that the riverine input was a source of DISn. Based on the data in this study, a preliminary estimate of the tin budget via riverine input and atmospheric deposition has been established. According to our estimate, about 2 × 10(6) and 8.47 × 10(5) g/year of tin reach Bohai Bay via rivers and atmosphere. Environmental factors such as suspended particulate material, salinity, total organic matter, pH, nutrients, and phytoplankton had the important influences on DISn distribution. Among them, the negative correlation between DISn and phytoplankton at most stations might indicate the biological uptake of tin.

Fraction characteristics of rare earth elements in the surface sediment of Bohai Bay, North China.

Surface sediment samples were collected at 27 stations of Bohai Bay, North China. Sequential extractions were carried out in this study. REE were leached out from four labile fractions: Exchangeable (L1), bound to carbonates (L2), bound to Fe-Mn oxides (L3), bound to organic matter (L4), and the remainder was residual (R5). The total contents of REE fluctuate slightly in Bohai Bay, and are mainly concentrated in the middle region, showing relatively higher levels in the north than that in the south of Bohai Bay. Percentages of L1, L2, L3, L4, and R5 for REE suggest that the residual fraction accounts for the major component of REE, whereas Fe-Mn oxides also play important roles in combining labile REE. As the REE complex is not stabilized, the competition of complex could induce dissociation of the complex and redistribution of the REE in various environments. According to REE patterns and Y/Ho ratios of samples, REE are not anthropogenic or oceanic sources but riverine input, whereas suitable environment varieties can slightly affect the patterns and fractionations of REE. As powerful tracers for the variable of environment, higher anomaly of Eu and Ce in southern regions indicates a greater reduction in the condition of surface sediment in the south than that in the north of Bohai Bay.

Analysis on ecological status and spatial-temporal variation of Tamarix chinensis forest based on spectral characteristics and remote sensing vegetation indices.

The reserve of Tamarix forest, located in Changyi, China, is the only national marine special reserve taking Tamarix as the main object of protection. Compared with conventional monitoring technology, remote sensing technology can more comprehensively reflect the ecological environment status and spatial-temporal variation of monitoring objects. Based on spectral characteristics and remote sensing vegetation indices, the ecological status and spatial-temporal variation of Tamarix chinensis forest in the reserve deserve further exploration. Therefore, spectral characteristic, typical vegetation indices, comprehensive health index, VFC, and REP were analyzed based on Sentinel-2A images. Spatial-temporal variation analysis during 2014 to 2018 was analyzed based on GF-1 images. The research result indicated that ecological quality of protection zone showed an overall growth trend with the help of artificial ecological restoration, and it is possible to continuously implement ecological recovery towards the protection zone.