Halophytic succulence is a driver of the leaf non-structural carbohydrate contents in plants in the arid and hyper-arid deserts of northwestern China.

BACKGROUND AND AIMS: Non-structural carbohydrates (NSC), primarily sugars and starch, play a crucial role in plant metabolic processes and a plant's ability to tolerate and recover from drought stress. Despite their importance, our understanding of NSC characteristics in the leaves of plants that thrive in hyper-arid and saline environments remains limited. METHODS: To investigate the variations in leaf NSC across different species and spatial scales, and to explore their possible causes, we collected 488 leaf samples from 49 native plant species at 115 sites in the desert area of northwestern China. The contents of soluble sugars (SS), starch, and total NSC were then determined. KEY RESULTS: The average contents of SS, starch, and total NSC were 26.99, 60.28, and 87.27 mg g-1 respectively, which are much lower than those reported for Chinese forest plants and global terrestrial plants. Herbaceous and woody plants had similar NSC levels. In contrast, succulent halophytes, a key component of desert flora, showed significantly lower leaf SS and total NSC contents than non-succulent plants. We observed a strong negative correlation between leaf succulence and SS content, suggesting a role of halophytic succulence in driving multi-species NSC pools. Environmental factors explained a minor portion of the spatial variation in leaf NSC, possibly due to the narrow climatic variation in the study area, and soil properties, particularly soil salinity, emerged as more significant contributors. CONCLUSIONS: Our findings increase the understanding of plant adaptation to drought and salt stress, emphasizing the crucial role of halophytic succulence in shaping the intricate dynamics of leaf NSC across diverse plant species in arid and hyper-arid environments.

Desertification indirectly affects soil fauna by reducing complexity of soil habitats and diversity of energy sources.

Soil fauna is closely linked to ecological functions such as biogeochemical cycling, soil structure, ecosystem sustainability and trophic interactions. However, little consideration has been given to how desertification influences the abundance and diversity of soil fauna in arid areas. In this study, soil fauna was sampled in four desert habitats (gravel, sand, salt and mud desert) in northwest China. At the same time, the plant traits, geographic location and soil properties were investigated. We also measured contribution of environmental factors explained faunal community diversity and abundance, and by what pathways desertification controls soil fauna. The results showed that total abundance and diversity of soil fauna in the mud desert were significantly (P < 0.05) higher than salt, sand and gravel deserts. Soil fauna diversity, composition and community were more sensitive to desertification-induced changes in soil properties than to changes in plant traits and geographic locations (changes in soil properties explained 68.9 % and 73.7 % of the variation in diversity and abundance of soil fauna community, respectively). Among them, the available phosphorus, volumetric water content had a significant positive effect on community diversity and abundance, while pH had a significant negative effect (P < 0.01). The results of piecewise structural equation modeling imply that desertification may have mainly indirect impacts on soil fauna community, and that direct effects are almost zero. In summary, regardless of the type of desertification, it will affect the material cycle, energy flow and information transfer of ecosystems by destroying the soil habitats and vegetation conditions, and will affect the structure and diversity of soil fauna from the bottom up.

Syntax-Guided Content-Adaptive Transform for Image Compression.

The surge in image data has significantly increased the pressure on storage and transmission, posing new challenges for image compression technology. The structural texture of an image implies its statistical characteristics, which is effective for image encoding and decoding. Consequently, content-adaptive compression methods based on learning can better capture the content attributes of images, thereby enhancing encoding performance. However, learned image compression methods do not comprehensively account for both the global and local correlations among the pixels within an image. Moreover, they are constrained by rate-distortion optimization, which prevents the attainment of a compact representation of image attributes. To address these issues, we propose a syntax-guided content-adaptive transform framework that efficiently captures image attributes and enhances encoding efficiency. Firstly, we propose a syntax-refined side information module that fully leverages syntax and side information to guide the adaptive transformation of image attributes. Moreover, to more thoroughly exploit the global and local correlations in image space, we designed global-local modules, local-global modules, and upsampling/downsampling modules in codecs, further eliminating local and global redundancies. The experimental findings indicate that our proposed syntax-guided content-adaptive image compression model successfully adapts to the diverse complexities of different images, which enhances the efficiency of image compression. Concurrently, the method proposed has demonstrated outstanding performance across three benchmark datasets.

Fucoidan alleviates the inhibition of protein digestion by chitosan and its oligosaccharides.

Chitosan (CTS) and chitosan oligosaccharides (COS) have been widely applied in food industry due to their bioactivities and functions. However, CTS and COS with positive charges could interact with proteins, such as whey protein isolate (WPI), influencing their digestion. Interaction among CTS/COS, FUC, and WPI/enzymes was studied by spectroscopy, chromatography, and chemical methods in order to reveal the role of FUC in relieving the inhibition of protein digestibility by CTS/COS and demonstrate the action mechanisms. As shown by the results, the addition of FUC increased degree of hydrolysis (DH) and free protein in the mixture of CTS and WPI to 3.1-fold and 1.8-fold, respectively, while raise DH value and free protein in the mixture of COS and WPI to 6.7-fold and 1.2-fold, respectively. The interaction between amino, carboxyl, sulfate, and hydroxyl groups from carbohydrates and protein could be observed, and notably, FUC could interact with CTS/COS preferentially to prevent CTS/COS from combining with WPI. In addition, the addition of FUC could also relieve the combination of CTS to trypsin, increasing the fluorescence intensity and concentration of trypsin by 83.3 % and 4.8 %, respectively. Thus, the present study demonstrated that FUC could alleviate the inhibitory effect of CTS/COS on protein digestion.

A Real-world Dataset and Benchmark For Foundation Model Adaptation in Medical Image Classification.

Foundation models, often pre-trained with large-scale data, have achieved paramount success in jump-starting various vision and language applications. Recent advances further enable adapting foundation models in downstream tasks efficiently using only a few training samples, e.g., in-context learning. Yet, the application of such learning paradigms in medical image analysis remains scarce due to the shortage of publicly accessible data and benchmarks. In this paper, we aim at approaches adapting the foundation models for medical image classification and present a novel dataset and benchmark for the evaluation, i.e., examining the overall performance of accommodating the large-scale foundation models downstream on a set of diverse real-world clinical tasks. We collect five sets of medical imaging data from multiple institutes targeting a variety of real-world clinical tasks (22,349 images in total), i.e., thoracic diseases screening in X-rays, pathological lesion tissue screening, lesion detection in endoscopy images, neonatal jaundice evaluation, and diabetic retinopathy grading. Results of multiple baseline methods are demonstrated using the proposed dataset from both accuracy and cost-effective perspectives.

Chitosan and its oligosaccharide accelerate colonic motility and reverse serum metabolites in rats after excessive protein consumption.

Excessive protein consumption (EPC) could increase the gastrointestinal burden and impair gut motility. The present study was designed to explore the improvement of chitosan (CTS) and chitosan oligosaccharide (COS) on colonic motility and serum metabolites in rats after EPC. The results of in vivo experiments fully proved that CTS and COS could improve gut motility and reverse the serum metabolites in rats as indicated by LC-MS/MS analysis, and the COS group even showed a better effect than the CTS group. Furthermore, short-chain fatty acids (SCFAs), which could promote gut motility, were also increased to alleviate EPC-induced constipation after supplementation with CTS or COS. In addition, CTS and COS could decrease the concentration of ammonia in serum and down-regulate the levels of H2S and indole. In summary, the present study revealed that CTS and COS could produce SCFAs, improve the colonic motility in rats, reverse the levels of valine, adenosine, cysteine, 1-methyladenosine, indole, and uracil, and enhance aminoacyl-tRNA biosynthesis and valine, leucine and isoleucine degradation. The present study provides novel insights into the potential roles of CTS and COS in alleviating the adverse effects of EPC.

Structural characterization of a fucoidan from Ascophyllum nodosum and comparison of its protective effect against cellular oxidative stress with its analogues.

In the present study, a fucoidan fraction (ANP-3) was isolated from Ascophyllum nodosum, and the combined application of desulfation, methylation, HPGPC, HPLC-MSn, FT-IR, GC-MS, NMR, and Congo red test elucidated ANP-3 (124.5 kDa) as a triple-helical sulfated polysaccharide constituted by →2)-α-Fucp3S-(1→, →3)-α-Fucp2S4S-(1→, →3,6)-ß-Galp4S-(1→, →3,6)-ß-Manp4S-(1→, →3,6)-ß-Galp4S-(1→，→6)-ß-Manp-(1→, →3)-ß-Galp-(1→, α-Fucp-(1→, and α-GlcAp-(1→ residues. To better understand the relationship between the fucoidan structure of A. nodosum and protective effects against oxidative stress, two fractions ANP-6 and ANP-7 were used as contrast. ANP-6 (63.2 kDa) exhibited no protective effect against H2O2-induced oxidative stress. However, ANP-3 and ANP-7 with the same molecular weight of 124.5 kDa could protect against oxidative stress by down-regulating reactive oxygen species (ROS) and malondialdehyde (MDA) levels and up-regulating total antioxidant capability (T-AOC), superoxide dismutase (SOD), catalase (CAT), and glutathione peroxidase (GPX) activities. Then metabolites analysis indicated that arginine biosynthesis and phenylalanine, tyrosine, and tryptophan biosynthesis metabolic pathways and metabolic biomarkers such as betaine were involved in the effects of ANP-3 and ANP-7. The better protective effect of ANP-7 compared to that of ANP-3 could be attributed to its relatively higher molecular weight, sulfate substitution and →6)-ß-Galp-(1→ content, and lower uronic acid content.

Soil extracellular enzyme stoichiometry reflects microbial metabolic limitations in different desert types of northwestern China.

Soil extracellular enzyme activity (EEA) stoichiometry reflects the dynamic balance between microorganism metabolic demands for resources and nutrient availability. However, variations in metabolic limitations and their driving factors in arid desert areas with oligotrophic environments remain poorly understood. In this study, we investigated sites in different desert types in western China and measured the activities of two C-acquiring enzymes (ß-1,4-glucosidase and ß-D-cellobiohydrolase), two N-acquiring enzymes (ß-1,4-N-acetylglucosaminidase and L-leucine aminopeptidase), and one organic-P-acquiring enzyme (alkaline phosphatase) to quantify and compare the metabolic limitations of soil microorganisms based on their EEA stoichiometry. The ratios of log-transformed C-, N-, and P-acquiring enzyme activities for all deserts combined were 1:1.1:0.9, which is close to the hypothetical global mean EEA stoichiometry (1:1:1). We quantified the microbial nutrient limitation by means of vector analysis using the proportional EEAs, and found that microbial metabolism was co-limited by soil C and N. For different desert types, the microbial N limitation increased in the following order: gravel desert < sand desert < mud desert < salt desert. Overall, the study area's climate explained the largest proportion of the variation in the microbial limitation (17.9 %), followed by soil abiotic factors (6.6 %) and biological factors (5.1 %). Our results confirmed that the EEA stoichiometry method can be used in microbial resource ecology research in a range of desert types, and that the soil microorganisms maintained community-level nutrient element homeostasis by adjusting enzyme production to increase uptake of scarce nutrients even in extremely oligotrophic environments such as deserts.

Ascophyllum nodosum polysaccharide regulates gut microbiota metabolites to protect against colonic inflammation in mice.

Ascophyllum nodosum polysaccharide (ANP) can protect against colonic inflammation but the underlying mechanism is still unclear. This study has determined the metabolites of gut microbiota regulated by ANP to reveal the mechanism of the anti-inflammation effect of ANP. Using an in vitro colonic fermentation model, the results indicate that gut microbiota could utilize a proportion of ANP to increase the concentrations of short-chain fatty acids (SCFAs) and decrease ammonia content. Metabolomics revealed that 46 differential metabolites, such as betaine, L-carnitine, and aminoimidazole carboxamide ribonucleotide (AICAR), could be altered by ANP. Metabolic pathway analysis showed that ANP mainly up-regulated the phenylalanine, tyrosine, and tryptophan biosynthesis and aminoacyl-tRNA biosynthesis, which were negatively correlated with inflammation progression. Interestingly, these metabolites associated with inflammation were also up-regulated by ANP in colitis mice, including betaine, L-carnitine, AICAR, N-acetyl-glutamine, tryptophan, and valine, which were mainly associated with amino acid metabolism and aminoacyl-tRNA biosynthesis. Furthermore, the metabolites modulated by ANP were associated with the relative abundances of Akkermansia, Bacteroides, Blautia, Coprobacillus, Enterobacter, and Klebsiella. Additionally, based on VIP values, betaine is a key metabolite after the ANP supplement in vitro and in vivo. As indicated by these findings, ANP can up-regulate the production of SCFAs, betaine, L-carnitine, and AICAR and aminoacyl-tRNA biosynthesis to protect against colonic inflammation and maintain intestinal health.

H2O2-TiO2 photocatalytic degradation of chondroitin sulfate and in vivo absorption and excertion of its product.

Chondroitin sulfate (CS) is widely known for its various biological activities which are closely related to the sulfate substitution and the molecular weight. Effective degradation methods without striping sulfate groups are in a need. In the present study, a photocatalytic degradation method using H2O2 and TiO2 has been developed and it could decrease the average molecular weight of CS into 5 kDa within 6 h. The chemical composition of CS before and after degradation were compared by FT-IR, NMR, etc., and no removement of sulfate group was observed. Then the identification of the oligosaccharides in the degradation product by mass spectroscopy revealed that glucuronic acid or its derivative, arabinuronic acid, was at most of the reducing ends, and the depolymerization mechanism was proposed. Furthermore, the absorption of CS in rats was enhanced by the degradation while the excertion profile of the degradation product was similar to that of CS.

Interaction between Bacteroidetes species in the fermentation of Lycium barbarum arabinogalactan.

The present study investigated the utilization of an arabinogalactan from Lycium barbarum (LBP-3) by intestinal Bacteroidetes species. The mixed-culture assay showed 58.4 % LBP-3 was utilized, and Bacteroides caccae and Phocaeicola vulgatus utilized more LBP-3 in single-culture compared to others. During in vitro fermentation of LBP-3, P. vulgatus favored arabinose while B. caccae preferred galactose. Moreover, 9 and 25 oligosaccharides were identified by HPLC-MSn in conditioned media (CM) derived from B. caccae and P. vulgatus, respectively. All of 3 tested Parabacteroides species (P. distasonis, P. goldsteinii, and P. johnsonii) markedly proliferated in CM of B. caccae and P. vulgatus, and proliferations of B. uniformis, B. finegoldii, B. ovatus and B. thetaiotaomicron also increased significantly in CM of B. caccae. The study suggests that the ability of Bacteroidetes species to degrade LBP-3 and sheds light on cooperative interactions of Bacteroides, Phocaeicola, and Parabacteroides species in the presence of LBP-3.

Theoretical study on the electronic properties of different types of the donor:acceptor complexes.

Non-fullerene organic solar cells can be classified into four forms in line with the different types of donor (D) and acceptor (A) in the active layer: all-polymer (PD:PA), polymer D:small-molecule A (PD:MA), small-molecule D:polymer A (MD:PA), and all-small-molecule (MD:MA). On the basis of having studied the electronic properties of a large number of related monomer molecules and D:A complexes, this work constructed four groups of D:A molecular pairs as described above as examples to investigate their electronic properties with first-principles density functional theory. The results show that the absolute value of the average binding energy of the PD:PAcomplex D18:P(NDI2HD-T) is larger than others, indicating the structure is relatively more stable. In accordance of the Bader charge analysis, the intra-molecular charge transfer of small-molecule is greater than polymers. For these blends, the intermolecular charge transfer of the all-polymer pair D18:P(NDI2HD-T) is larger, revealing that the PD:PApair may result in a stronger intermolecular dipole electric field, which is beneficial to facilitate the separation of excitons. In addition, the MD:MApair DRTB-T:FDICTF-2Cl and the PD:MAcomplex D18:FDICTF-2Cl all exhibit a larger amount of intra-molecular charge transfer, which indicates that the small-molecule acceptors in D:A complexes are conducive to promoting intra-molecular charge transfer.

Chitosan and chitosan oligosaccharide influence digestibility of whey protein isolate through electrostatic interaction.

Chitosan (CTS)/chitosan oligosaccharide (COS) and whey protein isolate (WPI) have been frequently used as food supplements, but notably, the interaction between the carbohydrate and the protein may affect the digestibility of protein. Thus, the present study focused on effects of the interaction between CTS/COS and WPI on the protein digestibility. A series of chemical and spectroscopic techniques including gel electrophoresis, gel permeation chromatography, Fourier transform-infrared (FT-IR) spectroscopy, intrinsic fluorescence (IF) spectroscopy, and circular dichroism (CD) spectroscopy were applied. According to the findings, both CTS and COS dramatically reduced intestinal digestibility of WPI, resulting in a decrease of DH by 43.33 % and 52.31 %, respectively. The substitution degree of WPI on CTS was 0.87 g WPI/g CTS, and the electrostatic interaction between amine groups of CTS and carboxyl groups of WPI caused changes in WPI's stability, microstructure, and fluorescence intensity. Notably, CTS affected the digestibility of WPI by precipitating protein and enzyme, whereas COS altered WPI's digestibility by decreasing or inactivating enzyme activity. The present study offered a solid scientific foundation for the rational formulations of carbohydrates and proteins in food industry.

Two Ascophyllum nodosum Fucoidans with Different Molecular Weights Inhibit Inflammation via Blocking of TLR/NF-κB Signaling Pathway Discriminately.

The present study aimed to clarify the potential mechanism of fucoidans found in Ascophyllum nodosum on anti-inflammation and to further explore the relationship between their structures and anti-inflammation. Two novel fucoidans named ANP-6 and ANP-7 and found in A. nodosum, were separated and purified and their structures were elucidated by HPGPC, HPLC, GC-MS, FT-IR, NMR, and by the Congo red test. They both possessed a backbone constructed of →2)-α-L-Fucp4S-(1→, →3)-α-L-Fucp2S4S-(1→, →6)-ß-D-Galp-(1→, and →3,6)-ß-D-Galp4S-(1→ with branches of →2)-α-L-Fucp4S-(1→ and →3)-ß-D-Galp-(1→. Moreover, ANP-6 and ANP-7 could prevent the inflammation of the LPS-stimulated macrophages by suppressing the NO production and by regulating the expressions of iNOS, COX-2, TNF-α, IL-1ß, IL-6, and IL-10. Their inhibitory effects on the TLR-2 and TLR-4 levels suggest that they inhibit the inflammation process via the blocking of the TLR/NF-κB signal transduction. In addition, ANP-6, with a molecular weight (63.2 kDa), exhibited stronger anti-inflammatory capabilities than ANP-7 (124.5 kDa), thereby indicating that the molecular weight has an influence on the anti-inflammatory effects of fucoidans.

Digestion behavior of a polysaccharide from Cyclina sinensis: An explanation for the discrepancy in its immunostimulatory activities in vitro and in vivo.

Although numerous polysaccharides have demonstrated potential immunostimulatory activities in in vitro models, only a few of them successfully stimulate the immune system in vivo. In order to explore the possible reasons for the activity loss of polysaccharides in in vivo models, the immunostimulatory activities in vitro and in vivo and the digestion behavior of a polysaccharide from Cyclina sinensis (CSP) were investigated in the present study. CSP showed obvious immunostimulatory activity in a RAW 264.7 cell model. In in vitro experiment, CSP did not exhibit cytotoxicity at concentrations of ≤10 µg/ml, and significantly increased NO production at concentrations of 0.4-10 µg/ml, suggesting CSP processes immunostimulatory activity in vitro. Further investigation using simulated digestion model indicated that CSP could bind with the protein in the digestive fluids to form precipitate in both the stomach and small intestine, and it could be seriously degraded by amylase during the digestion in the small intestine. Furthermore, the in vivo immunostimulatory activity evaluation demonstrated CSP had no effect on immunosuppressed mice as indicated by the body weight, thymus and spleen indexes, and TNF-α, IL-1ß, IL-6, and IL-10 mRNA expression. Thus, the present study indicates that the degradation and precipitation of CSP in the digestive tract are the possible reasons for the activity loss of CSP after digestion. PRACTICAL APPLICATION: Cyclina sinensis is the common aquatic shellfish in China and plays an important role in the marine aquaculture industry. Cyclina sinensis polysaccharide (CSP) is the main active component of C. sinensis. The structure characterization and immunostimulatory activity of a purified fraction of CSP (CSP-1) and the effect of digestion on CSP and its immunostimulatory activity were studied. The result of this study promotes the understanding of the nutritional function effects and provides a scientific reference for the rational development and high-value utilization of C. sinensis.

Anti-obesity effects of Laminaria japonica fucoidan in high-fat diet-fed mice vary with the gut microbiota structure.

Previous studies have indicated that fucoidan could resist high-fat-diet (HFD)-induced obesity by modulating the composition of gut microbiota. However, the outcome of dietary intervention may differ between individuals due to large inter-individual variability in gut microbiota. Thus, the present study aimed to investigate the possible discrepancy of the anti-obesity effects of fucoidan supplementation in HFD-fed mice models with different gut microbiota communities. In the present study, the anti-obesity effects of fucoidan isolated from Laminaria japonica (FucLj) on normal mice and microbiota-altered mice treated with penicillin or metronidazole were compared and investigated. The 16S rRNA sequencing revealed the differences of gut microbiota among penicillin-treated, metronidazole-treated and normal groups, and mice treated with penicillin were characterized by greater relative abundance of the phylum Bacteroidetes and the families Muribaculaceae and Bacteroidaceae. Furthermore, FucLj ameliorated HFD-induced body weight gain, fat accumulation, serum lipid profiles, insulin resistance, hepatic steatosis and adipocyte hypertrophy in penicillin-treated and untreated mice, while no effects were observed in metronidazole-treated mice. Overall, mice with different initial gut microbiota responded differently to FucLj supplementation on a high-fat diet, and metronidazole-sensitive gut bacteria negatively correlated with obesity symptoms and were required for the anti-obesity effects of FucLj. Moreover, the anti-obesity effects were not dependent on the utilization of FucLj by gut microbiota to produce SCFAs. These findings indicate that evaluation of the gut microbiota structure before dietary interventions is helpful for enhancing the beneficial outcomes of dietary fiber supplementation and provide a rationale for the further application of dietary fucoidan in a personalized way.

Differences and spatial variations of plant leaf calorific value in deserts of the Hexi Corridor, Northwestern China.

The leaf calorific value (LCV) is an important trait that indicates how efficiently a plant utilizes natural resources to capture energy. However, little is known about the LCV characteristics of plants in arid and hyper-arid environments. To investigate the spatial patterns and variations in LCV of desert plants and their possible causes, we collected 343 leaf samples of 52 species along a 1000-km transect in the desert area of northwestern China. We analyzed the gross calorific value (GCV), ash-free calorific value (AFCV), carbon content (CC), nitrogen content (NC), and ash content (AC) of the leaves. The mean leaf GCV and AC were 16.2 kJ g-1 (range from 8.9 to 20.1 kJ g-1), and 189.8 mg g-1 (range from 61.5 to 495.1 mg g-1) respectively, which differ significantly from the values for plants growing in more humid areas of China. Succulence was the dominant trait that drove the differences in leaf GCV and AFCV among plant functional groups. Succulent plants had significantly lower leaf GCV and AFCV, and significantly higher AC, than non-succulent plants, indicating that the investment of energy for succulent plants in response to drought stress may be lower than that for non-succulent plants. Among the biological factors that affected LCV, the CC and AC were the main determinants of leaf GCV, whereas CC and NC were the main determinants of leaf AFCV. Drought stress is an environmental constraint that has a direct negative effect on both leaf GCV and AFCV, but its contribution may be weaker than phylogenetic effects. Our results suggest that LCV is a useful leaf trait that can be used to evaluate plant-environment interactions from an energy perspective.

Automated detection of myopic maculopathy from color fundus photographs using deep convolutional neural networks.

BACKGROUND: Myopic maculopathy (MM) has become a major cause of visual impairment and blindness worldwide, especially in East Asian countries. Deep learning approaches such as deep convolutional neural networks (DCNN) have been successfully applied to identify some common retinal diseases and show great potential for the intelligent analysis of MM. This study aimed to build a reliable approach for automated detection of MM from retinal fundus images using DCNN models. METHODS: A dual-stream DCNN (DCNN-DS) model that perceives features from both original images and corresponding processed images by color histogram distribution optimization method was designed for classification of no MM, tessellated fundus (TF), and pathologic myopia (PM). A total of 36,515 gradable images from four hospitals were used for DCNN model development, and 14,986 gradable images from the other two hospitals for external testing. We also compared the performance of the DCNN-DS model and four ophthalmologists on 3000 randomly sampled fundus images. RESULTS: The DCNN-DS model achieved sensitivities of 93.3% and 91.0%, specificities of 99.6% and 98.7%, areas under the receiver operating characteristic curves (AUC) of 0.998 and 0.994 for detecting PM, whereas sensitivities of 98.8% and 92.8%, specificities of 95.6% and 94.1%, AUCs of 0.986 and 0.970 for detecting TF in two external testing datasets. In the sampled testing dataset, the sensitivities of four ophthalmologists ranged from 88.3% to 95.8% and 81.1% to 89.1%, and the specificities ranged from 95.9% to 99.2% and 77.8% to 97.3% for detecting PM and TF, respectively. Meanwhile, the DCNN-DS model achieved sensitivities of 90.8% and 97.9% and specificities of 99.1% and 94.0% for detecting PM and TF, respectively. CONCLUSIONS: The proposed DCNN-DS approach demonstrated reliable performance with high sensitivity, specificity, and AUC to classify different MM levels on fundus photographs sourced from clinics. It can help identify MM automatically among the large myopic groups and show great potential for real-life applications.

Evaluation of an OCT-AI-Based Telemedicine Platform for Retinal Disease Screening and Referral in a Primary Care Setting.

PURPOSE: To evaluate the performance of a telemedicine platform integrated with optical coherence tomography (OCT) and artificial intelligence (AI) techniques for retinal disease screening and referral. METHODS: We constructed an OCT-AI-based telemedicine platform and deployed it at four primary care stations located in Jing'an district, Shanghai, to detect retinal disease cases among aged groups and refer them to Shanghai Tenth People's Hospital (TENTH Hospital). Two ophthalmologists jointly graded the data set collected from this pilot application, and then the performance of this platform was analyzed from multiple aspects. RESULTS: This study included 1257 participants between July 2020 and September 2020, of whom 394 had retinal pathologies and 146 were even considered urgent cases by the ophthalmologists. The OCT-AI models achieved a sensitivity of 96.6% (95% confidence interval [CI], 91.8%-98.7%) and specificity of 98.8% (95% CI, 98.0%-99.3%) for detecting urgent cases and a sensitivity of 98.5% (95% CI, 96.5%-99.4%) and specificity of 96.2% (95% CI, 94.6%-97.3%) for detecting both urgent and routine cases. Coupled with AI, our platform reduced the workload of human consultation by 96.2% for massive normal cases. The detected disease cases received online medical suggestions at an average time of 21.4 hours via this platform. CONCLUSIONS: This platform can automatically identify patients with retinal disease with high sensitivity and specificity, support timely human consultation, and bring necessary referrals. TRANSLATIONAL RELEVANCE: The OCT-AI-based telemedicine platform shows great practical value for retinal disease screening and referral in a real-world primary care setting.

Preparation of Low-Molecular-Weight Fucoidan with Anticoagulant Activity by Photocatalytic Degradation Method.

It is a challenge to degrade sulfated polysaccharides without stripping sulfate groups. In the present study, a photocatalytic method was applied to degrade fucoidan, a sulfated polysaccharide from brown algae. The degradation with varying addition amounts of H2O2 and TiO2 were monitored by high performance gel permeation chromatography (HPGPC) and thin layer chromatography (TLC), and fucoidan was efficiently degraded with 5% TiO2 and 0.95% H2O2. A comparison of the chemical compositions of 2 products obtained after 0.5 h and 3 h illumination, DF-0.5 (average Mw 90 kDa) and DF-3 (average Mw 3 kDa), respectively, with those of fucoidan indicates the photocatalytic degradation did not strip the sulfate groups, but reduced the galactose/fucose ratio. Moreover, 12 oligosaccharides in DF-3 were identified by HPLC-ESI-MSn and 10 of them were sulfated. In addition, DF-0.5 showed anticoagulant activity as strong as fucoidan while DF-3 could specifically prolong the activated partial thromboplastin time. All samples exerted inhibition effects on the intrinsic pathway FXII in a dose-dependent manner. Thus, photocatalytic degradation demonstrated the potential to prepare sulfated low-molecular-weight fucoidan with anticoagulant activity.