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Septic arthritis (SA) is more severe in patients with rheumatoid arthritis, joint surgical issues, or a weakened immune system. Timely diagnosis of SA is crucial for effective treatment. Traditional diagnostic methods such as ELISA, white blood cell counting, blood culture, qPCR, and imaging techniques are often less accurate and time-consuming. Researchers are focusing on developing highly sensitive biosensors for SA using blood-based biomarkers. Procalcitonin is a protein and a well-established biomarker for SA. This research focuses on developing a procalcitonin interdigitated electrode (IDE) biosensor using a probe made of an aptamer and antibody-modified gold nanoparticle (AuNP) complex. The probe was attached to the IDE through an amine linker and then interacted with procalcitonin. AuNPs increased the attachment of the aptamer and antibody to the IDE, enabling the detection of procalcitonin at levels as low as 10 ng/mL, with a linear regression curve ranging from 10 to 100 ng/mL [y = 4.0691x - 2.1887; R2 = 0.9937]. Furthermore, procalcitonin-spiked serum elevated the current level with increasing procalcitonin concentrations, while control performances did not enhance the current, indicating the selective and specific detection of procalcitonin. This AuNP-aptamer-antibody complexed biosensor effectively identifies procalcitonin at low levels and aids in the diagnosis of SA.

Background Endometriosis is an underdiagnosed disorder that affects an estimated 6-10% of women of reproductive age. Endometriosis has been reported in epidemiological studies to be associated with autoimmune diseases. However, the relationship remains controversial. Methods A meta-analysis of observational studies was undertaken to evaluate the risk of autoimmune diseases in patients with endometriosis. The relevant studies were retrieved via the databases Medline, Embase and Web of Science until July 20, 2023. Mendelian randomization (MR) was subsequently utilized to scrutinize the causal influence of genetic predisposition toward endometriosis on three autoimmune diseases. Results The meta-analysis findings revealed a relationship between endometriosis and the onset of SLE (cohort studies: RR = 1.77, 95% confidence interval (CI): 1.47–2.13, I2 = 0%; Case-control and cross-sectional studies: OR = 5.23, 95% CI: 0.74–36.98, I2 = 98%), RA (cohort studies: RR = 2.18, 95% CI: 1.85–2.55, I2 = 92%; Case-control and cross-sectional studies: OR = 1.40, 95% CI: 1.19–1.64, I2 = 0%) and SS (cohort studies: RR = 1.49, 95% CI: 1.34–1.66, I2 = 0%). Similarly, in our MR study, the results of the inverse-variance-weighted (IVW) model suggested that genetic predisposition to endometriosis was causally associated with an increased risk for SLE (OR = 1.915, 95% CI: 1.204–3.045, p = 0.006) and RA (OR = 1.005, 95% CI: 1.001–1.009, p = 0.014). Conclusions Both our meta-analysis and MR study indicate that endometriosis increases the risk of autoimmune diseases. These findings not only broaden our understanding of the genetic mechanisms underlying the comorbidity of endometriosis and autoimmune diseases, but also offer a new strategy for autoimmune disease prevention.

Genetically modified maize (Zea mays L.) MON810 was approved for importation into China for feed use in 2004; however, the localization data concerning exogenous insertion sequences, which confer insect resistance, have been questionable. MON810 maize plants discovered in northeastern China were used to analyze the molecular characteristics of the exogenous insertion. Using PacBio-HiFi sequencing and PCR assays, we found the insertion was located in chromosome 8, and there was a CaMV35S promoter, hsp70 intron, and insecticide gene cry1Ab, except for genome sequence insertion in the MON810 event. Importantly, the 5′ and 3′ flanking sequences were located in the region of 55869747–55879326 and 68416240–68419152 on chromosome 5, respectively. The results of this study correct previous results on the genomic localization of the insertion structure for the MON810 event. We also found a single-nucleotide polymorphism (SNP) in the hsp70 intron, which is most likely the first SNP found in a transgenic insertion sequence. PCR amplification in conjunction with Sanger sequencing, allele-specific PCR (AS-PCR), and blocker displacement amplification (BDA) assays were all effective at detecting the base variance. The integrated strategy used in this study can serve as a model for other cases when facing similar challenges involving partially characterized genetic modification events or SNPs.

The contamination of Atlantic salmon with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has impeded the development of the cold-chain food industry and posed possible risks to the population. Electron beam (E-beam) irradiation under 2, 4, 7, and 10 kGy can effectively inactivate SARS-CoV-2 in cold-chain seafood. However, there are few statistics about the quality changes of salmon exposed to these irradiation dosages. This work demonstrated that E-beam irradiation at dosages capable of killing SARS-CoV-2 induced lipid oxidation, decreased vitamin A content, and increased some amino acids and ash content. In addition, irradiation altered the textural features of salmon, such as its hardness, resilience, cohesiveness, and chewiness. The irradiation considerably affected the L*, a*, and b* values of salmon, with the L* value increasing and a*, b* values decreasing. There was no significant difference in the sensory evaluation of control and irradiated salmon. It was shown that irradiation with 2−7 kGy E-beam did not significantly degrade quality. The inactivation of SARS-CoV-2 in salmon is advised at a dose of 2 kGy.

Abstract Background Abnormal tau accumulation and cholinergic degeneration are hallmark pathologies in the brains of patients with Alzheimer’s disease (AD). However, the sensitivity of cholinergic neurons to AD-like tau accumulation and strategies to ameliorate tau-disrupted spatial memory in terms of neural circuits still remain elusive. Methods To investigate the effect and mechanism of the cholinergic circuit in Alzheimer's disease-related hippocampal memory, overexpression of human wild-type Tau (hTau) in medial septum (MS)-hippocampus (HP) cholinergic was achieved by specifically injecting pAAV-EF1α-DIO-hTau-eGFP virus into the MS of ChAT-Cre mice. Immunostaining, behavioral analysis and optogenetic activation experiments were used to detect the effect of hTau accumulation on cholinergic neurons and the MS-CA1 cholinergic circuit. Patch-clamp recordings and in vivo local field potential recordings were used to analyze the influence of hTau on the electrical signals of cholinergic neurons and the activity of cholinergic neural circuit networks. Optogenetic activation combined with cholinergic receptor blocker was used to detect the role of cholinergic receptors in spatial memory. Results In the present study, we found that cholinergic neurons with an asymmetric discharge characteristic in the MS-hippocampal CA1 pathway are vulnerable to tau accumulation. In addition to an inhibitory effect on neuronal excitability, theta synchronization between the MS and CA1 subsets was significantly disrupted during memory consolidation after overexpressing hTau in the MS. Photoactivating MS-CA1 cholinergic inputs within a critical 3 h time window during memory consolidation efficiently improved tau-induced spatial memory deficits in a theta rhythm-dependent manner. Conclusions Our study not only reveals the vulnerability of a novel MS-CA1 cholinergic circuit to AD-like tau accumulation but also provides a rhythm- and time window-dependent strategy to target the MS-CA1 cholinergic circuit, thereby rescuing tau-induced spatial cognitive functions. Graphical Abstract

The structure and expression of exogenous genes in transgenic crops are critical for the target traits. R7569 has the same exogenous insertion structure as the transgenic insect-resistant cotton MON531 but with a deletion in the 3′ end of the cry1Ac gene and the terminator region. Thus, in the present study, transcription, expression, and insecticidal activity assays were conducted to determine the function of the truncated cry1Ac gene. R7569 has a truncated cry1Ac gene with a length of 2554 bp encoding 881 amino acids, and the transcription termination site was mainly concentrated downstream of the truncated position and extended 160–270 bp from the truncated position using rapid amplification of cDNA ends (RACE). The transcript levels of the cry1Ac gene in R7569 were significantly higher than those of MON531 implants, except for during the boll stage. The content of the Cry1Ac protein in R7569 was higher than that of MON531 in the cotton leaf in all three periods. The corrected mortality rates of R7569 and MON531 against bollworms were 93.09% and 88.83%, respectively. The LC50 value of R7569 was 0.732 ng/g (dw), indicating a high level of resistance to bollworm. In this study, for the first time, we found a partial deletion of the target gene in commercially applied transgenic crops, and the partial deletion of the 3′ end of the cry1Ac gene retained a better transcription, expression level, and insecticidal activity, which can provide a specific case for the safety evaluation of transgenic crops.

The use of global standards, and the placement of barcodes and data matrix codes on vaccine labels and other levels of packaging are crucial elements for the traceability of finished vaccine products. Vaccine manufacturers are committed to improving health through their products, as vaccine production offers opportunities that can be leveraged to benefit immunization systems. In 2019 the Developing Countries Vaccine Manufacturers Network (DCVMN) created the Supply Chain Initiative aimed at prioritize and explore traceability opportunities; concomitantly procurement agencies announced traceability requirements for vaccine global supply. Vaccine traceability brings benefits including supply chain reliability and safety through enhanced product movement visibility, and a reduction of falsified and expired vaccines circulating in the supply chain. DCVMN has coordinated the development and implementation of global traceability standards, at both primary and secondary vaccine packaging levels, to encourage and enable sharing these experiences. Six pilot studies in four different countries showed successful implementation, and constituted part of larger vaccine traceability work within the respective organizations. The main findings from these pilot studies indicated that stepwise approaches to the adoption of traceability standards allowed vaccine manufacturers to learn by doing, initially with lower risk, and to spread their investments over time. Because the value of traceability is in its scale of adoption and the use of the data, it remains important for all stakeholders to engage in and prioritize the journey of vaccine traceability, but also to suitably manage the financial risks. The DCVMN Supply Chain Initiative has demonstrated that its members are committed to driving supply system changes that benefit immunization, while recognizing that supply chain traceability is part of a larger healthcare ecosystem and should be adopted by countries and immunization programmes as well.

Marine actinomycetes produce a substantial number of natural products with cytotoxic activity. Actinomycete strains have been isolated from sources including fishes, coral, sponges, seaweeds, mangroves and sediments. These cytotoxic compounds can be broadly categorized into four classes: polyketides; non-ribosomal peptides and hybrids; isoprenoids and hybrids; and others, among which the majority are polyketides (146 of 254). Twenty-two of the 254 compounds show potent cytotoxicity, with IC50 values at the ng/mL or nM level. This review highlights the sources, structures and antitumor activity of 254 natural products isolated from marine actinomycetes and first reported between 1989 and 2020.

Abstract Purpose To explore the influence of irrigating fluid at different temperatures on patients' body temperature and local inflammatory mediators during spinal endoscopy. Methods 110 cases of intervertebral foramen surgery in our hospital from January 2019 to October 2021 were randomly divided into control group and observation group. Operations of both groups were performed by the same experienced chief physician. The observation group was irrigated with 37 °C constant temperature saline, while the control group was irrigated at room temperature. The effect was evaluated by monitoring the intraoperative temperature, postoperative VAS score and the levels of inflammatory factors, such as TNF-α, IL-1, IL-6 and IL-10 in drainage fluid. Results After 30 min of operation, overall temperature of the control group dropped significantly, and 50 cases (90.9%) had hypothermia, P 0.05. The VAS score of observation group was significantly lower than that of control group at 6 h and 1 month after operation, P

PurposeHealth disparities are driven by a complex interplay of determinants operating across multiple levels of influence. However, while recognized conceptually, much disparities research fails to capture this inherent complexity in study focus and/or design; little of such work accounts for the interplay across the multiple levels of influence from structural (contextual) to biological or clinical. We developed a novel modeling framework that addresses these challenges and provides new insights.MethodsWe used data from the Florida Cancer Data System on endometrial cancer patients and geocoded-derived social determinants of health to demonstrate the applicability of a new modeling paradigm we term PRISM regression. PRISM is a new highly interpretable tree-based modeling framework that allows for automatic discovery of potentially non-linear hierarchical interactions between health determinants at multiple levels and differences in survival outcomes between groups of interest, including through a new specific area-level disparity estimate (SPADE) incorporating these multilevel influences.ResultsPRISM demonstrates that hierarchical influences on racial disparity in endometrial cancer survival appear to be statistically relevant and that these better predict survival differences than only using individual level determinants. The interpretability of the models allows more careful inspection of the nature of these hierarchical effects on disparity. Additionally, SPADE estimates show distinct geographical patterns across census tracts in Florida.ConclusionPRISM can provide a powerful new modeling framework with which to better understand racial disparities in cancer survival.

Vegetation photosynthesis is a critical component of terrestrial carbon cycles, and its peak value (peak photosynthetic rate) dominates plant CO2 uptake. Urbanization has significantly influenced vegetation photosynthesis by changing environmental conditions directly (replacement of vegetated surfaces with impervious surfaces) and indirectly (e.g., atmospheric and climatic conditions). Although some studies have investigated the effects of urbanization on vegetation productivity across the whole study area, how the peak photosynthetic rate responds to urbanization for different vegetation types has received scant scholarly attention. Here, using the urban-rural gradient approach, we explored the effects of urbanization on the peak photosynthetic rate (surrogated by GPPmax and EVImax) of different vegetation types across urbanization intensity (UI) gradients in the Yangtze River Delta Urban Agglomeration (YRDUA). The results showed that (1) the GPPmax and EVImax of the forest, grassland, and wetland decreased with urban intensity. GPPmax and EVImax in rural areas (UI ≦ 1%) were 36.62 and 30.47% higher than those of urban areas (UI > 1%) overall vegetation types. (2) The indirect impacts can offset or exacerbate the direct loss of vegetation photosynthesis caused by urbanization in YRDUA. Especially for forest ecosystems in YRDUA, the negative direct urbanization effect is exacerbated by the indirect reduction in vegetation growth. However, the indirect effects of urbanization on grassland and wetland offset 47.08 and 87.23% loss of GPPmax, and 34.17 and 79.73% loss of EVImax due to the reduction of vegetated surface area, respectively. (3) The indirect impact of urbanization on vegetation photosynthesis was dominated by the elevated daytime land surface temperature (LSTday). Our study highlights the necessity of distinguishing the various effects of urbanization on vegetation photosynthesis, which may help stakeholders formulate more reasonable urban environmental planning.

Abstract Recent years have witnessed a growing trend of utilizing reviews to improve the performance and interpretability of recommender systems. Almost all existing methods learn the latent representations from the user’s and the item’s historical reviews and then combine these two representations for rating prediction. The fatal limitation in these methods is that they are unable to utilize the most predictive review of the target user for the target item since such a review is not available at test time. In this paper, we propose a novel recommendation model, called AGTR, which can generate the unseen target review with adversarial training for rating prediction. To this end, we develop a unified framework to combine the rating tailored generative adversarial nets for synthetic review generation and the neural latent factor module using the generated target review along with historical reviews for rating prediction. Extensive experiments on four real-world datasets demonstrate that our model achieves the state-of-the-art performance in both rating prediction and review generation tasks.

Following ischemic insult, neovascularization and vascular remodelling play an essential part in the repair of brain damage. Here the authors show that neutrophil extracellular traps serve a detrimental role in the regeneration process, limiting the functional recovery of the brain post injury.

To alleviate grassland degradation and improve ecosystem functions, the Chinese government has implemented some ecological projects since 2004 across the Tibetan Plateau, such as ‘Return Grazing Land to Grassland Project’ and the ‘Compensation and Rewards to Herders for Natural Grassland Conservation’. Meanwhile, the frequency and intensity of drought events have strengthened in this plateau. However, how grasslands respond to these projects and drought remains controversial. Here, taking the northern Tibetan Plateau (NTP) as the study area, we first quantified the spatiotemporal changes in the annual maximum grassland NDVI (NDVImax) after the implementation of the ecological projects (2005–2015). Then, we assessed the effects of drought (Standardized Precipitation-Evapotranspiration Index, SPEI) and ecological projects on the dynamics of NDVImax. The results showed that (1) the grazing intensity decreased significantly across the NTP after the start of ecological projects, but grassland NDVImax did not increase as expected. Statistically, 53.7% of grasslands showed a decreasing NDVImax, of which 5.7% had a significant decrease (P

Sclerotinia sclerotiorum is a necrotrophic phytopathogenic fungus that produces sclerotia. Sclerotia are essential components of the survival and disease cycle of this devastating pathogen. In this study, we analyzed comparative transcriptomics of hyphae and sclerotia. A total of 1959 differentially expressed genes, 919 down-regulated and 1040 up-regulated, were identified. Transcriptomes data provide the possibility to precisely comprehend the sclerotia development. We further analyzed the differentially expressed genes (DEGs) in sclerotia to explore the molecular mechanism of sclerotia development, which include ribosome biogenesis and translation, melanin biosynthesis, autophagy and reactivate oxygen metabolism. Among these, the autophagy-related gene SsAtg1 was up-regulated in sclerotia. Atg1 homologs play critical roles in autophagy, a ubiquitous and evolutionarily highly conserved cellular mechanism for turnover of intracellular materials in eukaryotes. Therefore, we investigated the function of SsAtg1 to explore the function of the autophagy pathway in S. sclerotiorum. Deficiency of SsAtg1 inhibited autophagosome accumulation in the vacuoles of nitrogen-starved cells. Notably, ΔSsAtg1 was unable to form sclerotia and displayed defects in vegetative growth under conditions of nutrient restriction. Furthermore, the development and penetration of the compound appressoria in ΔSsAtg1 was abnormal. Pathogenicity analysis showed that SsAtg1 was required for full virulence of S. sclerotiorum. Taken together, these results indicate that SsAtg1 is a core autophagy-related gene that has vital functions in nutrient utilization, sclerotia development and pathogenicity in S. sclerotiorum.

Zearalenone (ZEA) is known as a Fusarium-produced mycotoxin, representing a risk to cereal food safety with repercussions for economies and worldwide trade. Recent studies have reported the co-occurrence of ZEA and masked ZEA in a variety of cereals and cereal-based products, which may exert adverse effects on public health due to additive/synergistic interactions. However, the co-contamination of ZEA and masked ZEA has received little attention. In order to minimize the threats of co-contamination by ZEA and masked ZEA, it is necessary to recognize the occurrence and formation of ZEA and masked ZEA. This review focuses on the characteristics, incidence, and detection of ZEA and its masked forms. Additionally, the fate of ZEA and masked ZEA during the processing of bread, cake, biscuits, pasta, and beer, as well as the ZEA limit, are discussed. The incidence of masked ZEA is lower than that of ZEA, and the mean level of masked ZEA varies greatly between cereal samples. Published data showed a considerable degree of heterogeneity in the destiny of ZEA during cereal-based food processing, mostly as a result of the varying contamination levels and complicated food processing methods. Knowledge of the fate of ZEA and masked ZEA throughout cereal-based food processing may reduce the likelihood of severe detrimental market and trade ramifications. The revision of legislative limits of masked ZEA may become a challenge in the future.

This study evaluated the effect of grape seed-derived monomer, dimeric, and trimeric procyanidins on rat pheochromocytoma cell line (PC12) cells and in a zebrafish Parkinson’s disease (PD) model. PC12 cells were cultured with grape seed-derived procyanidins or deprenyl for 24 h and then exposed to 1.5 mm 1-methyl-4-phenylpyridinium (MPP+) for 24 h. Zebrafish larvae (AB strain) 3 days post-fertilization were incubated with deprenyl or grape seed-derived procyanidins in 400 µM 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) for 4 days. The results showed that the procyanidin dimers procyanidin B1 (B1), procyanidin B2 (B2), procyanidin B3 (B3), procyanidin B4 (B4), procyanidin B1-3-O-gallate (B1-G), procyanidin B2-3-O-gallate (B2-G), and the procyanidin trimer procyanidin C1 (C1) had a protective effect on PC12 cells, decreasing the damaged dopaminergic neurons and motor impairment in zebrafish. In PC12 cells and the zebrafish PD model, procyanidin (B1, B2, B3, B4, B1-G, B2-G, C1) treatment decreased the content of reactive oxygen species (ROS) and malondialdehyde (MDA), increased the activity of antioxidant enzymes glutathione peroxidase (GSH-Px), catalase (CAT), and superoxide dismutase (SOD), and upregulated the expression of nuclear factor-erythroid 2-related factor (Nrf2), NAD(P)H: quinone oxidoreductase 1 (NQO1), and heme oxygenase-1 (HO-1). These results suggest that in PC12 cells and the zebrafish PD model, the neuroprotective effects of the procyanidins were positively correlated with their degree of polymerization.

Drought events cause ecological problems, including reduced water resources and degraded vegetation. Quantifying vegetation responses to drought is essential for ecological management. However, in existing research, the response relationships (correlations and lags) were typically determined based on Pearson correlation coefficient and the resultant lag times were constrained by the spatial and temporal resolutions of the analyzed data. Inner Mongolia is an important ecological barrier in northern China. Ecological security is one of the most concerned issues of the region’s sustainable development. Herein, we combined Global Inventory Modeling and Mapping Studies (GIMMS) normalized difference vegetation index (NDVI3g) with Systeme Probatoire d’Observation de la Terra-vegetation (SPOT-VGT) NDVI data through spatial downscaling. The obtained 1 km-resolution NDVI dataset spanning Inner Mongolia from 1982 to 2019 was used to represent the refined vegetation distribution. The standardized precipitation evapotranspiration index (SPEI) derived from gridded meteorological data was used to measure drought over the same period. We investigated the spatiotemporal characteristics of vegetation and drought in the region in the past 38 years. We then discussed changes in different vegetation responses to drought across eastern Inner Mongolia using cross wavelet transform (XWT) and wavelet coherence (WTC). The results reveal that in 82.4% of the study area, NDVI exhibited rising trends, and the SPEI values exhibited declining trends in 78.5% of the area. In eastern Inner Mongolia, the grassland NDVI was positively correlated with SPEI and significantly affected by drought events, while NDVI in forestlands, including shrubs, broad-leaved forests, and coniferous forests, was negatively correlated with SPEI in the short term and weakly affected by drought. The NDVI lag times behind SPEI in grasslands, coniferous forests, and broad-leaved forests were 1–1.5, 4.5, and 7–7.5 months, respectively. These findings provide a scientific foundation for environmental preservation in the region.

Sorting nexins are a conserved protein family involved in many cellular processes in fungi, and the function of sorting nexin Snx4 (Atg24) and Snx41 (Atg20) in Cochliobolus heterostrophus was not clear. The ΔChsnx4 and ΔChsnx41 mutants were generated by a PCR-based marker method to determine the roles of Snx4 and Snx41 in reproductive development, stress adaption, and virulence in C. heterostrophus. Compared with the wild-type strain, the ΔChsnx4 and ΔChsnx41 mutants exhibited obvious changes in vegetative growth and in morphology of conidia. In addition, the conidiation, appressorium formation, and virulence of snx4 and snx41 mutants were dramatically reduced. Moreover, ΔChsnx4 and ΔChsnx41 mutants were more sensitive to oxidative stress (menadione and H2O2), cell wall integrity stress (Congo red and calcofluor white), fungicides, and isothiocyanates. All the phenotypes mentioned above were restored in complemented strains. In addition, ChSnx4 and ChSnx41 were proven to interact with each other through yeast two-hybrid. Taken together, these findings indicated that ChSNX4 and ChSNX41 were important for fungal growth, asexual development, stress adaption, and virulence in C. heterostrophus.

Abstract Tau accumulation and cholinergic impairment are characteristic pathologies in Alzheimer's disease (AD). However, the causal role of tau accumulation in cholinergic lesion is elusive. Here, we observed an aberrant tau accumulation in the medial septum (MS) of 3xTg and 5xFAD mice, especially in their cholinergic neurons. Overexpressing hTau in mouse MS (MShTau) for 6 months but not 3 months induced spatial memory impairment without changing object recognition and anxiety‐like behavior, indicating a specific and time‐dependent effect of MS‐hTau accumulation on spatial cognitive functions. With increasing hTau accumulation, the MShTau mice showed a time‐dependent cholinergic neuron loss with reduced cholinergic projections to the hippocampus. Intraperitoneal administration of donepezil, a cholinesterase inhibitor, for 1 month ameliorated the MS‐hTau‐induced spatial memory deficits with preservation of MS–hippocampal cholinergic pathway and removal of tau load; and the beneficial effects of donepezil was more prominent at low dose. Proteomics revealed that MS‐hTau accumulation deregulated multiple signaling pathways with numerous differentially expressed proteins (DEPs). Among them, the vacuolar protein sorting‐associated protein 37D (VP37D), an autophagy‐related protein, was significantly reduced in MShTau mice; the reduction of VP37D was restored by donepezil, and the effect was more significant at low dose than high dose. These novel evidences reveal a causal role of tau accumulation in linking MS cholinergic lesion to hippocampus‐dependent spatial cognitive damages as seen in the AD patients, and the new tau‐removal and autophagy‐promoting effects of donepezil may extend its application beyond simple symptom amelioration to potential disease modification.

Grassland classification is crucial for grassland management. One commonly used method utilizes remote sensing vegetation indices (VIs) to map grassland classes at various scales. However, most grassland classifications were conducted as case studies in a small area due to lack of field data sources. At a small scale, classification is reliable; however, great uncertainty emerges when extended to other areas. In this study, large amounts of field observations (more than 30,000 aerial photos) were obtained using unmanned aerial vehicle photography in Inner Mongolia, China, during the peak period of grassland growth in 2018 and 2019. Then, four machine learning classification algorithms were constructed based on characteristic indices of MODIS NDVI in the growing season to map grassland classes of Inner Mongolia. Finally, the spatial distribution and temporal variation of temperate grassland classes were analyzed. Results showed that: (1) Among all characteristic indices, the maximum, average, and sum of MODIS NDVI from July to September during 2015 to 2019 greatly affected grassland classification. (2) The random forest method exhibited the best performance with overall accuracy and kappa coefficient being 72.17% and 0.62, respectively. (3) Compared with the grassland class mapped in the 1980s, 30.98% of grassland classes have been transformed. Our study provides a technological basis for effective and accurate classification of the temperate steppe class and a theoretical foundation for sustainable development and restoration of the temperate steppe ecosystem.

This study evaluated the relationship between the neuroprotective effects of procyanidins and their structural characteristics. In vitro, a rat pheochromocytoma cell line (PC12) was exposed to the grape seed-derived procyanidin monomers: catechin (C), epicatechin (EC), and epicatechin gallate (ECG); the procyanidin dimers: procyanidin B1 (B1), procyanidin B2 (B2), procyanidin B3 (B3), procyanidin B4 (B4), procyanidin B1-3-O-gallate (B1-G), and procyanidin B2-3-O-gallate (B2-G); and the procyanidin trimers: procyanidin C1 (C1) and N-acetyl-l-cysteine (NAC) for 24 h. Cells were then incubated with 200 μM H2O2 for 24 h. In vivo, zebrafish larvae (AB strain) 3 days post-fertilization were incubated with NAC or procyanidins (C, EC, ECG, B1, B2, B3, B4, B1-G, B2-G, C1) in 300 µM H2O2 for 4 days. Different grape seed procyanidins increased the survival of PC12 cells challenged with H2O2, improved the movement behavior disorder of zebrafish caused by H2O2, inhibited the increase of ROS and MDA and the decrease of GSH-Px, CAT, and SOD activities, and up-regulated the Nrf2/ARE pathway. The neuroprotective effects of the procyanidin trimer C1 treatment group were greater than the other treatment groups. These results suggest that the neuroprotective effect of procyanidins is positively correlated with their degree of polymerization.

This research assessed the molecular mechanism of procyanidins (PCs) against neurotoxin 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) and its metabolite 1-methyl-4-phenylpyridinium (MPP+) induced Parkinson’s disease (PD) models. In vitro, PC12 cells were incubated with PCs or deprenyl for 24 h, and then exposed to 1.5 mM MPP+ for 24 h. In vivo, zebrafish larvae (AB strain) 3 days post-fertilization (dpf) were incubated with deprenyl or PCs in 400 μM MPTP for 4 days. Compared with MPP+/MPTP alone, PCs significantly improved antioxidant activities (e.g., glutathione peroxidase (GSH-Px), superoxide dismutase (SOD), catalase (CAT)), and decreased levels of reactive oxygen species (ROS) and malondialdehyde (MDA). Furthermore, PCs significantly increased nuclear Nrf2 accumulation in PC12 cells and raised the expression of NQO1, HO-1, GCLM, and GCLC in both PC12 cells and zebrafish compared to MPP+/MPTP alone. The current study shows that PCs have neuroprotective effects, activate the nuclear factor-erythroid 2-related factor 2 (Nrf2)/antioxidant response element (ARE) pathway and alleviate oxidative damage in MPP+/MPTP-induced PD models.

Net primary productivity (NPP) and precipitation-use efficiency (PUE) are crucial indicators in understanding the responses of vegetation to global change. However, the relative contributions of climate change and human interference to the dynamics of NPP and PUE remain unclear. During the past few decades, the impacts of climate change and human activities on alpine grasslands on the Qinghai-Tibet Plateau (QTP) have been intensifying. The aims of the study were to investigate the spatiotemporal patterns of grassland NPP and PUE on the QTP during 2000–2017 and quantify how much of the variance in NPP and PUE can be attributed to the climatic factors (precipitation and temperature) and grazing intensity. The results showed that: (1) grassland NPP significantly increased with a rate of 0.6 g C m−2 year−1 over the past 18 years, mainly induced by the increased temperature and the enhanced precipitation. The temperature was the dominant factor for NPP interannual variation in mid-eastern QTP, and precipitation restrained vegetation growth most in the southwest and northeast. (2) The PUE was higher on the eastern and western parts of the plateau, but lower at the center. Regarding grassland types, the PUE of alpine steppe (0.19 g C m−2 mm−1) was significantly lower than those of alpine meadow (0.31 g C m−2 mm−1) and desert steppe (0.32 g C m−2 mm−1). (3) Precipitation was significantly and negatively correlated with PUE and contributed the most to the temporal variation of grassland PUE on the QTP (52.7%). (4) Furthermore, we found that the grazing activities had the lowest contributions to both NPP and PUE interannual variation, compared to temperature and precipitation. Thus, it is suggested that climate variability rather than grazing activities dominated vegetation changes on the QTP.

This study evaluated the neuroprotective effects and mechanisms of procyanidins (PCs). In vitro, rat pheochromocytoma cells (PC12 cells) were exposed to PCs (1, 2 or 4 μg/mL) or N-Acetyl-L-cysteine (NAC) (20 μM) for 24 h, and then incubated with 200 μM of H2O2 for 24 h. Compared with H2O2 alone, PCs significantly increased antioxidant activities (e.g., glutathione peroxidase (GSH-Px), superoxide dismutase (SOD), catalase (CAT)), decreased levels of reactive oxygen species (ROS) and malondialdehyde (MDA), and increased nuclear factor-erythroid 2-related factor 2 (Nrf2) accumulation and increased the expression of quinone oxidoreductase 1 (NQO1), heme oxygenase 1 (HO-1), glutamate-cysteine ligase modifier subunit (GCLM), and glutamate-cysteine ligase catalytic subunit (GCLC). In vivo, zebrafish larvae (AB strain) 3 days post-fertilization (dpf) were exposed to NAC (30 μM) or PCs (4, 8 or 16 μg/mL) in the absence or presence of 300 μM of H2O2 for 4 days. Compared with H2O2 alone, PCs enhanced antioxidant activities (e.g., GSH-Px, CAT, and SOD), decreased levels of ROS and MDA, and enhanced Nrf2/ antioxidant response element (ARE) activation and raised expression levels of NQO1, HO-1, GCLM, and GCLC. In conclusion, these results indicated that PCs exerted neuroprotective effects via activating the Nrf2/ARE pathway and alleviating oxidative damage.

Antarctic krill oil is high in nutritional value and has biological functions like anti-inflammation and hypolipidemic effects. But it has and unpleasant smell, and unsaturated fatty acids are prone to oxidative deterioration. Its high viscosity and low solubility in water make it difficult for processing. Microemulsion can be a new promising route for development of krill oil product. We determined a formula of krill oil-in-water microemulsion with krill oil: isopropyl myristate = 1:3 as oil phase, Tween 80:Span 80 = 8:2 as surfactant, ethanol as co-surfactant and the mass ratio of surfactant to co-surfactant of 3:1. After screening the formula, we researched several characteristics of the prepared oil-in-water microemulsion, including electrical conductivity, microstructure by transmission electron microscope and cryogenic transmission electron microscope, droplet size analysis, rheological properties, thermal behavior by differential scanning calorimeter and stability against pH, salinity, and storage time.

Soybean tissue and arthropods were collected in Bt soybean fields in China at different times during the growing season to investigate the exposure of arthropods to the plant-produced Cry1Ac toxin and the transmission of the toxin within the food web. Samples from 52 arthropod species/taxa belonging to 42 families in 10 orders were analysed for their Cry1Ac content using enzyme-linked immunosorbent assay (ELISA). Among the 22 species/taxa for which three samples were analysed, toxin concentration was highest in the grasshopper Atractomorpha sinensis and represented about 50% of the concentration in soybean leaves. Other species/taxa did not contain detectable toxin or contained a concentration that was between 1 and 10% of that detected in leaves. These Cry1Ac-positive arthropods included a number of mesophyll-feeding Hemiptera, a cicadellid, a curculionid beetle and, among the predators, a thomisid spider and an unidentified predatory bug belonging to the Anthocoridae. Within an arthropod species/taxon, the Cry1Ac content sometimes varied between life stages (nymphs/larvae vs. adults) and sampling dates (before, during, and after flowering). Our study is the first to provide information on Cry1Ac-expression levels in soybean plants and Cry1Ac concentrations in non-target arthropods in Chinese soybean fields. The data will be useful for assessing the risk of non-target arthropod exposure to Cry1Ac in soybean.