Dynamic pathology and pathogen distribution of the yeast Metschnikowia bicuspidata in the Chinese mitten crab (Eriocheir sinensis).

In this study, the "milky disease" model of Eriocheir sinhensis was constructed via intramuscular injection with the pathogenic yeast Metschnikowia bicuspidata. The dynamic pathological changes of E. sinensis after injection were elucidated with two staining methods (haemotoxylin-eosin and alcian blue periodic acid-Schiff) and fluorescence in situ hybridization technology. Anatomical observation revealed three stages of the "milky disease": no clinical signs (1-4 days after infection), the appearance of signs of disease (5-7 days), and significant liquefaction (10 days). Histological observation also revealed three stages of the disease: yeast diffusion (1-2 days after infection), yeast slow development (3-4 days), and yeast rapid proliferation (5 days). And FISH technique was suitable for the early detection of infection with M. bicuspidata in E. sinensis. We found that M. bicuspidata spread to the whole body of the crab through the haemolymph and developed into fungal septicaemia. These results elucidate the systemic pathological characteristics of "milky disease" in E. sinensis and suggest the pathogenic mechanism of M. bicuspidata.

Exploring the mechanism of Sendeng-4 against rheumacid arthritis through integrated serum pharmacochemistry, transcriptomics, and network pharmacology.

Mongolian medicine Sendeng-4 (SD-4) has demonstrated satisfactory clinical treatment outcomes for rheumatoid arthritis (RA); nevertheless, its bioactive components and the related mechanisms have not yet been clearly elucidated. To explore the bioactive chemical components of SD-4 in the treatment of RA and its possible mechanisms, an High Performance Liquid Chromatography-tandem mass spectrometry (HPLC-MS/MS) method was established to simultaneously quantify the main components in SD-4, and ultraperformance LC-Q-Exactive-MS/MS (UPLC-Q-Exactive-MS/MS) was used to identify the phytochemicals absorbed in the serum. Then, using network pharmacology methods, these components were constructed into a compound-target network of RA to predict possible biological targets of SD-4 as well as potential signaling pathways. Transcriptomics analysis and molecular docking were used to validate the results of network pharmacology. Subsequently, we established a complete Freund's adjuvant-induced RA rat model and observed the anti-RA effects of SD-4 through assessments of foot swelling, ankle diameter, arthritis score, morphology, serum inflammatory factors, and histopathological analysis of synovial tissue. Specifically, reverse transcription-quantitative polymerase chain reaction, Western blot, and immunohistochemical analysis were used in animal experiments to validate the pathways of serum phytochemistry, network pharmacology, and transcriptomics. Tannic acid, gallic acid, corilagin, crocin I, gardenoside, ferulic acid, quercetin, limonin, rutin, chlorogenic acid, verbascoside, catechin, epicatechin, myricetin, and dihydromyricetin in SD-4 showed good linearity within their respective concentration ranges (r ≥ 0.9991); the average recovery rate was 93.77%-109.17% (relative standard deviation < 2%). A total of 37 compounds were identified in serum samples. Based on this, network pharmacology methods collected 739 genes related to these identified compounds in SD-4 and 3807 genes related to RA. Network pharmacology and transcriptomic analysis demonstrated that the phosphatidylinositol 3-kinase (PI3K)-protein kinase B (Akt) signaling pathway is the most relevant pathway affected by SD-4 in RA. In the experiments, SD-4 treatment reduced ankle swelling and arthritis scores in RA rats, improved symptoms, and reduced the production of inflammatory factors. Compared with the RA model group, SD-4 treatment significantly reduced the expression of PI3K-Akt pathway-related messenger RNA and proteins. In addition, immunohistochemical analysis confirmed these results. This study combined serum phytochemistry, network pharmacology, and transcriptomics to demonstrate that SD-4 can alleviate RA by regulating the PI3K-Akt signaling pathway. This research provides a theoretical basis for the clinical application of SD-4 and offers an effective strategy for the identification of bioactive substances in traditional Chinese medicine formulas and the study of their potential mechanisms.

The controllable and efficient synthesis of two-dimensional metal-organic framework nanosheets for heterogeneous catalysis.

Two-dimensional (2D) MOFs exhibit unique periodicity in surface structures and thus have attracted much interest in the fields of catalysis, energy, and sensors. However, the expanded production scale of 2D MOFs had remained a great challenge in most previous studies. Herein, a controllable and efficient crystallization method for synthesizing 2D MOF nanosheets using high-gravity reactive precipitation is proposed, significantly improving heterogeneous catalysis efficiency. The two-dimensional ZIF-L nanosheets prepared in a rotating packed bed (RPB) reactor show a smaller lateral and lamellar thickness and a higher BET surface area compared to ZIF-L nanosheets prepared in a conventional stirred tank reactor (STR), with a greatly shortened reaction time. Applying the ZIF-L-RPB nanosheets as a catalyst, the catalytic Knoevenagel condensation as a probe reaction displays a high conversion rate of benzaldehyde (99.3%) within 2 h at room temperature, greatly exceeding that displayed by ZIF-L-STR and other reported catalysts. Furthermore, ZIL-L-RPB nanosheets of only 0.2 wt% enhanced the catalytic activity for the glycolysis of poly(ethylene terephthalate) (PET) with a PET conversion and a monomer yield of 90% in a short period of 15 min at 195 °C and almost completely depolymerized PET with a monomer yield of 94% in 30 min, which was far above that achieved by ZIL-L-STR. These results indicate the promising prospects of a high-gravity reactive precipitation strategy with precise size control in an economical way to prepare high-activity 2D MOF nanosheets for a wide range of heterogeneous catalysis.

Preparation and Photodegradation Properties of Carbon-Nanofiber-Based Catalysts.

In this study, an iron oxide/carbon nanofibers (Fe2O3/CNFs) composite was prepared by a combination of electrospinning and hydrothermal methods. The characterization of Fe2O3/CNFs was achieved via scanning electron microscopy (SEM), infrared spectroscopy (IR), X-ray diffraction (XRD) and X-ray photoelectron spectroscopy (XPS). It is shown that when the hydrothermal reaction time was 180 °C and the reaction time was 1 h, the Fe2O3 nanoparticle size was about 90 nm with uniform distribution. The photodegradation performance applied to decolorize methyl orange (MO) was investigated by forming a heterogeneous Fenton catalytic system with hydrogen peroxide. The reaction conditions for the degradation of MO were optimized with the decolorization rate up to more than 99% within 1 h, which can decompose the dyes in water effectively. The degradation process of MO by Fenton oxidation was analyzed by a UV-visible NIR spectrophotometer, and the reaction mechanism was speculated as well.

The complete mitochondrial genome sequence of the Metschnikowia bicuspidata (Metschnikoff, 1884), an emerging pathogen of 'milky disease' in Chinese mitten crab.

The outbreak of milky disease of Chinese mitten crab caused by M. bicuspidata seriously restricted the development of the crab industry. In this study, the mitochondrial genome sequence of M. bicuspidata was assembled, annotated, and further analyzed. The results indicated that the complete mitochondrial genome of M. bicuspidata was 75,095 bp, which contained two rRNAs, 23 tRNAs, and 13 protein-coding genes. The phylogenetic tree of 13 yeasts based on the complete mitochondrial genome was constructed which showed that M. bicuspidata (accession number OK514652) and M. bicuspidata (accession number MW147605.1) were clustered in a clade. To sum up, our research results would further provide essential data for the systematics and evolution study of M. bicuspidata.

Electrochemical Strategy for Analyzing the Co-evolution of Cu2+ and •OH Levels at the Early Stages of Transgenic AD Mice.

As more researchers have acknowledged that the aggregation of amyloid ß (Aß) peptides might only be a pathological phenomenon that appears during the course of Alzheimer's disease (AD), it is therefore of great significance to have a preclinical or an early clinical diagnosis. Cu2+ dyshomeostasis and oxidative stress, such as hydroxyl radical (•OH), are found to be associated with peptide aggregations. However, we still do not know how the levels of Cu2+ and •OH are altered in the brain before massive Aß plaques appear. Herein, we demonstrated the design and application of a sensitive electrochemical sensor to monitor Cu2+ and •OH simultaneously in one system without obvious cross-talk. The electrode was fabricated using black phosphorus-loaded Au (BP-Au) nanoparticles, which were then sequentially linked with DNA1, DNA2-labeled Au (Au-DNA2) nanoparticles, and methylene blue (MB). Cu2+ was first recognized and captured onto the sensor by BP with high selectivity and then produced a reduction current at around -0.01 V. The •OH quantification was established on the cleavage of the hybrid structure between DNA1 and BP-Au upon the appearance of •OH in the phosphate-buffered saline (PBS), leading to the depletion of the voltammetric response of MB around -0.25 V. Good linear correlations were obtained over concentrations of 0.5-127.5 µM for Cu2+ and 0.5-96.0 µM for •OH. Most importantly, the developed sensor was successfully applied to track the variations of the two species in brain tissues from APP/PS1 transgenic AD mice at the early stages before massive Aß plaques appeared.

Chinese trends in adolescent marriage and fertility between 1990 and 2015: a systematic synthesis of national and subnational population data.

BACKGROUND: Early marriage and fertility are major social determinants of health and wellbeing. Rapid shifts in the past three decades, including a rise in sexual activity in unmarried adolescents, a large population of young migrant workers, and a high proportion of males relative to females, have the potential to alter patterns of reproductive health in Chinese adolescents and young women. We aimed to establish long-term trends of marriage and fertility for girls and women aged 15-24 years in China. METHODS: We did a longitudinal study in which we extracted aggregated data for marriage and childbearing status for Chinese girls and women aged 15-24 years from the Chinese National Population Census (in 1990, 2000, and 2010) and the Chinese 1% National Population Sample Survey (in 1995, 2005, and 2015). The census included all individuals with Chinese nationality who resided in China when the survey was done. For the 1% sample survey, communities or villages were randomly selected and all residents with Chinese nationality in the selected communities or villages were included. In all censuses and sample surveys, forms that included information on basic demographic characteristics, education, marriage, and fertility were completed and verified by the census enumerators at the household residence, based on responses provided by the householder or another adult in the household. We calculated the ever-married rate and age-specific fertility rate (ASFR) for all included individuals. We built multivariate random-effects generalised least squares regression models on panel data to test whether marriage or fertility rate was associated with education level, sex ratio, and the proportion of the population who are an ethnic minority in a province. FINDINGS: The ever-married rate for those aged 15-19 years decreased from 4·7% in 1990 to 1·2% (95% CI 1·2-1·3) in 2000, but rebounded to 2·4% (2·4-2·5) in 2015. The ASFR for this age group decreased from 22·0 births per 1000 individuals in 1990 to 6·0 (5·9-6·0) births per 1000 in 2000, and rebounded to 9·2 (8·9-9·4) births per 1000 in 2015. The rebound was found in most provinces. In women aged 20-24 years, the ever-married rate generally declined from 58·6% in 1990 to 25·5% (95% CI 25·4-25·6) in 2015, and the ASFR decreased from 198·8 births per 1000 in 1990 to 55·0 (54·5-55·5) births per 1000 in 2015. In 2015, the ever-married rate and ASFR for girls and women in rural areas aged 15-19 years were three-times higher than those of their urban counterparts (3·8% [95% CI 3·7-3·9] vs 1·1% [1·1-1·1] for the ever-married rate and 15·4 [14·9-15·9] vs 4·1 [3·9-4·3] births per 1000 for the ASFR). There were large disparities in ever-married rate across individuals of different education levels, with increases in the ever-married rate of 15-19-year-olds not attending senior high school between 2000 and 2010. Those aged 15-19 years were more likely to be married or give birth in the western provinces. Education held a protective association against adolescent childbearing, whereas a high ratio of males to females and a high proportion of ethnic minorities were associated with greater risk. INTERPRETATION: Although China's total fertility rate remains far less than replacement, after a period of steady decline, there has been a rebound in adolescent marriage and childbearing in the past decade. A range of adolescent-targeted strategies will be needed across provinces, including scaling up comprehensive sex education, ensuring that girls continue in school, and providing adequate reproductive health services, which specifically meet the needs for modern contraception in sexually active unmarried girls. FUNDING: Humanities and Social Sciences Planning Fund Project, Sports and Health Special Project of Education and Scientific Research, and China Scholarship Council.

In vivo monitoring of superoxide anion from Alzheimer's rat brains with functionalized ionic liquid polymer decorated microsensor.

The superoxide anion (O2•-) is an important reactive oxygen species (ROS) in the brain system, which has been associated with the development of many neurological diseases, including Alzheimer's disease (AD). Herein, we introduced a carbon fiber microelectrode (CFME) based in vivo technique for specific and sensitive monitoring of the O2•- radical in the living brains of both normal and AD model rats. Compared with other reported superoxide dismutase (SOD) electrochemical biosensors, the microsensor presented in our work was featured in the coating of a functionalized ionic liquid polymer (PIL) onto PB nanoparticles (PBNPs) and carbon nanotubes (CNT). It was demonstrated that the cationic and carboxyl-rich PILs provided abundant interaction sites with SOD to prevent enzyme leakage from sensor, which was beneficial for the enhancement of sensitivity. Additionally, CCK-8 assay and autoxidation of pyrogallol tests showed that MCF-7 cells maintained a high viability after incubated with PIL and most of the SOD bioactivity was retained in the presence of PIL, which implied the PIL itself possessed an excellent biocompatibility. These properties allow the sensor to track the fluctuation of O2•- levels in vivo between normal and AD rats. This is the first report on application of functionalized PIL to reveal the O2•- related pathological process of AD.

Influence of socio-economic status on dietary quality of children and adolescents in Fangshan District, Beijing / 中国学校卫生

Objective@#To assess the effects of Socioeconomic status on the dietary quality of children and adolescents, and to provide the reference for improving primary students’ dietary quality.@*Methods@#A total of 2 496 students from 16 schools (4 urban primary schools, 4 rural primary schools, 4 urban middle schools, and 4 rural middle schools) in Fangshan District, Beijing, were included using a stratified cluster random sampling method. Information on 7-day intake of cereals, vegetables, fruits, meat and dairy was collected using questionnaires and dietary quality was graded according to the Dietary Guidelines for Chinese Residents (2016).@*Results@#The dietary quality for urban children and adolescents was better than that for rural ones. Compared with rural children, their urban peers had higher scores for intake of vegetables, fruits, and dairy (all were P<0.01), but lower scores for intake of meat (P=0.01). For children with parental education level of senior high school, the dietary scores were higher in urban areas (P<0.05), whereas no urban-rural disparity was found for children with higher educated parents (junior college or above, P=0.17). In children with monthly household income less than 5 000 yuan, the urban dietary scores were higher than that of rural areas (P<0.01), whereas in the group above 5 000 yuan, the difference between urban and rural areas was no longer statistically significant(P>0.05). The multi-factor analysis showed that living in urban areas, being girls, being younger, with higher educated parents and with higher monthly household income were protective factors for dietary quality. However, the effect of household income on dietary quality differed between urban and rural areas (P<0.05).@*Conclusion@#In the process of dietary guidance and intervention, children with relatively low socio-economic level should be given a priority to provide appropriate nutrition education and welfare policies.

Magnetic metal-organic frameworks for fast and efficient solid-phase extraction of six Sudan dyes in tomato sauce.

Magnetic solid-phase extraction is an effective and useful technique to preconcentrate trace analytes from food samples. In this study, a magnetic trimeric chromium octahedral metal-organic framework (Fe3O4-NH2@MIL-101) was fabricated and characterized. Fe3O4-NH2@MIL-101 was applied as an adsorbent of magnetic solid-phase extraction combined with high performance liquid chromatography to effectively isolate and simultaneously determine six Sudan dyes (Para Red, Sudan I-IV, and Sudan Red 7B) from tomato sauce. Potential factors affecting the MSPE were investigated in detail, and adsorption efficiency of Fe3O4-NH2@MIL-101 was compared with those of conventional adsorbents, such as neutral alumina, HLB, and C18. The developed method facilitated the extraction with using only 3 mg of adsorbent in 2 min. In addition, enhancement factors of 50, linear range of 0.01-25 µg/mL, and detection limit (S/N = 3) of 0.5-2.5 µg/kg were obtained. The intra-day and inter-day recoveries for spiked Sudan dyes were in the range of 72.6%-92.9% and 69.6%-91.6%, respectively, with relative standard deviations of ≤9.2%.

Effective extraction and simultaneous determination of Sudan dyes from tomato sauce and chili-containing foods using magnetite/reduced graphene oxide nanoparticles coupled with high-performance liquid chromatography.

A simple, effective, and robust magnetic solid-phase extraction method was developed using magnetite/reduced graphene oxide nanoparticles as the adsorbent for the simultaneous determination of Sudan dyes (I, II, III, and IV) in foodstuffs. The magnetite/reduced graphene oxide nanoparticles were characterized by X-ray diffraction, scanning electron microscopy, and vibrating sample magnetometry. The extraction parameters including extraction time, elution solution, and elution time and volume were investigated in detail. Such magnetite/reduced graphene oxide nanoparticles based magnetic solid-phase extraction in combination with high-performance liquid chromatography and variable wavelength detection gave the detection limits of 3-6 µg/kg for Sudan I-IV in chili sauce, tomato sauce, chili powder, and chili flake samples. The recoveries were 79.6-108% at three spiked levels with the intra- and inter-day relative standard deviations of 1.2-8.6 and 4.5-9.6%, respectively. The feasibility was further performed by a comparison with commercial alumina-N. This method is suitable for the routine analysis of Sudan dyes due to its sensitivity, simplicity, and low cost.