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Eriocheir sinensis is an important fishery resource in the Yangtze River basin, which has brought about huge socio-economic benefits. The estuarine spawning grounds of E. sinensis, however, has experienced negative effects, such as habitat alteration and degradation of the water environment, in the mid- to late 1980s as a result of the construction of water conservation projects, land reclamation along the estuary, and pollution input. In addition, the overexploitation of E. sinensis resources has contributed to a sharp decline in its resources. To develop rational and scientific habitat management plans, the estuarine spawning habitats of E. sinensis have received attention in recent years. Currently, the distribution pattern and habitat characteristics of E. sinensis spawning grounds in the Yangtze River estuary have been explored from the perspective of resource distribution; however, habitat quality has not been further investigated. Studies on habitat quality can more effectively support the development of fishery habitat management strategies by serving as a tool to objectively assess the functional status of aquatic habitats. The habitat quality of the Yangtze River estuary has a substantial impact on the resources of E. sinensis as it is the only spawning ground for this species in the Yangtze River basin and is also the largest in China. Therefore, the behavior of E. sinensis during reproduction and spawning, which reflects the habitat quality of the spawning grounds, served as the foundation for this study. The evaluation of the habitat quality of E. sinensis spawning grounds was based on the parameters of reproductive performance and quantitative distribution. The habitat quality index (HQI) of E. sinensis spawning grounds was built by screening evaluation indices, weight analysis of evaluation indices, and construction of evaluation criteria. To provide the necessary scientific tools for examining E. sinensis spawning grounds in the Yangtze River estuary and to establish a solid scientific foundation for managing estuarine spawning grounds for this species. The spawning grounds of the Yangtze River estuary were monitored using egg-holding crabs of E. sinensis, and sampling was performed using gillnets positioned at certain locations. Key environmental parameters influencing the spawning activity of E. sinensis, such as water depth, turbidity, dissolved oxygen (DO) in bottom water, salinity (SAL), and temperature (T) were gathered during the sampling process. Through anatomical measurements of collected egg-holding crabs, physiological characteristics including carapace width, absolute fecundity, relative fecundity, condition factor, hepatopancreas index, and reproductive effort were gathered and collected. The characteristics of egg-holding crab population distribution and reproductive success were key factors considered when choosing the evaluation indices. The catch per unit effort of egg-holding crabs is a quantitative distribution characteristic, and the reproductive performance characteristics primarily rely on correlation analysis to determine the traits that can objectively respond to the reproductive performance of egg-holding crab, which are RF and HSI. Subsequently, a hierarchical evaluation system is created based on the characteristics of the evaluation indices. The response relationship between the environmental elements and each evaluation index serves as the foundation for the weight analysis of the evaluation indices. The environmental factors were analyzed separately with each evaluation index for redundancy analysis (RDA), and the results of the RDA were used to understand the degree of influence of each evaluation index on environmental characteristics. It is also used as the basis for the weight value of the evaluation indices, and the weight value of each evaluation index is determined by combining the hierarchical analysis method. Finally, a multi-index comprehensive scoring technique was used to determine the HQI of the E. sinensis spawning grounds, and guidelines for evaluating habitat quality were developed. The findings revealed a strong response relationship between egg-holding crab reproductive performance characteristic indicators and environmental factors (91.9%, F=9.0, P=0.042), which has significant application value when assessing the habitat quality of their spawning grounds. The evaluation revealed that the survey sites´ HQIs ranged from 0.33 to 0.84, and 47% of the survey sites assigned a "medium" or higher rating to the habitat quality level. Overall, the northern bank of Hengsha had a greater habitat quality than the deepwater canal. The HQI developed in this study has obvious advantages in quantitatively assessing the habitat quality of E. sinensis spawning grounds because it has a greater interpretation rate of environmental elements (94.9%, F=12.0, P=0.038) than quantitative distribution characteristics. The maximum percentage of HQI was explained by DO, SAL, and T when each environmental factor was used as an independent explanatory variable, accounting for 74.0% (F=22.7, P=0.004), 44.0% (F=6.3, P=0.044), and 33.0% (F=3.9, P=0.076), respectively. DO, SAL, and T were the key environmental factors influencing the habitat quality of E. sinensis spawning grounds. In this study, the Yangtze River estuary was chosen as the spawning ground for E. sinensis, and the quantitative distribution and reproductive performance characteristics of this species were employed as the foundation for evaluating habitat quality. The spawning grounds of the Yangtze River estuary for E. sinensis were further investigated in terms of habitat function using the HQI, which was built based on the characteristics of the evaluation indices. This study identified the major habitat factors that influence the habitat quality of these spawning grounds.

Coilia nasus is a species of anadromous migratory fish, which predominantly lives in the sea. During the breeding season, the reproductive population migrates from the sea to rivers to reproduce and clusters to form a fishing season. The Yangtze Estuary is an important migration channel for this species. In recent years, due to the influence of upstream dam construction, water conservancy projects along the Yangtze River, environmental pollution and overfishing, the populations of this species in the Yangtze River are on the verge of extinction. In order to better protect C. nasus in the Yangtze River, a large number of studies on the conservation and management of its resources, migration habits, genetic structure, and the effects of resource recovery on this species have been conducted. As for the nutritional composition of C. nasus, studies have been conducted on the different sources, ecotypes, breeding methods, and stages of gonad development. These studies have mainly focused on the muscle nutrition of C. nasus from the Yangtze River; however, none have investigated the nutritional composition of different tissues of the reproductive populations from the Yangtze Estuary. This study is the first to determine the nutritional status of the reproductive population that migrates to the Yangtze Estuary with mature ovaries, and to compare and analyze the distribution characteristics of total lipids and fatty acids in different tissues, and provides reference information for ascertaining the nutritional status and reproductive performance of this species in the Yangtze Estuary. In this study, the contents of moisture, total lipid, and fatty acid composition in muscle, liver, and ovary tissues of adult female C. nasus with gonad development stage Ⅳ were measured and analyzed using standard GB methods. The results indicated that: The moisture content declined successively in muscle, liver, and ovary tissues, with measurements of (77.91±1.61)%, (75.01±1.33)%, and (46.77±5.58)%, respectively. The total lipid content of dry matter increased successively in muscle, liver, and ovary tissues, with measurements of (16.21±1.09)%, (21.94±1.23)%, and (55.21±1.35)%, respectively. The saturated fatty acids (SFA) content was (29.89±0.81)%, (37.60±3.06)%, and (18.33±1.61)% in the muscle, liver, and ovaries, respectively, with the highest in the liver and the lowest in the ovaries. There were significant differences in SFA contents among the three tissues (P0.05). The ratio of UFA/SFA in muscle, liver, and ovary tissues was 2.35, 1.67, and 4.49, respectively, and the ratio of n3-PUFA/n6-PUFA in the same three tissues was 4.94, 3.87, and 5.13, respectively. These ratios were highest in the ovary, followed by the muscle, and were the lowest in the liver. In summary, the total lipid, PUFA, EPA, DHA, and n3-PUFA contents and the ratios of UFA/SFA and n3-PUFA/n6-PUFA were highest in ovary tissues, and the distribution characteristics of the corresponding composition in different tissues was closely related to the reproductive habits of this species during gonad development stage Ⅳ. The accumulation of rich lipids and reasonable essential fatty acid nutrition in the ovary can improve the reproductive performance of C. nasus in this stage and provide sufficient nutrition and energy sources for the development of eggs and larvae in the subsequent stage. In this study, it was found that the lipid and polyunsaturated fatty acid nutrition of C. nasus adults with ovarian development to stage Ⅳ selectively accumulated in the ovary, which is an adaptation to the reproductive activities of this species at this stage. The results provide basic data for determining the differences in nutritional demands of C. nasus adults at different ovarian development stages and the mechanisms for the synthesis and transformation of essential fatty acids. Additionally, this study lays a foundation for further exploration of the relationship between ovarian nutritional status and egg quality. Relevant data can enrich the reproductive biology knowledge of this species and provide theoretical guidance for protecting the reproductive population and the maintenance of C. nasus spawning grounds in the waters adjacent to the Yangtze Estuary.

Chinese mitten crab (Eriocheir sinensis) belongs to Decapoda, Grapsidae and Eriocheir. It is also known as river crab and hairy crab and is widely distributed in the coastal waters of China and has important economic benefits. Salinity is the key environmental factor affecting the mating and spawning of E. sinensis. Presently, reports on the effects of salinity on crabs focus on osmotic pressure regulation, nutritional and energy metabolism, molting, and sexual precocity. However, the effects of salinity on the related hormones in the hemolymph before and after mating and spawning of E. sinensis have not been reported. Relevant steroid hormones include progesterone, 17α-dihydroxyprogesterone, 20β-dihydroxyprogesterone, and 17α-20β-dihydroxyprogesterone (DHP) and most effectively induce maturation of salmon and trout eggs, which has been confirmed in a variety of fish. Early studies have shown that the ovulation activity of fish is closely related to the level of gonadotropin (GTH) in the blood. The gonadotropin releasing hormone receptor (GnRHR) in E. sinensis indicate that the ovarian maturation and reproductive regulation in crustaceans are regulated by some gonadotropins, such as methylfarnesol and ecdysone. PGE, PGF, and prostacyclin (PGI2) can promote ovulation in a variety of fish and crustaceans. Like vertebrates, steroids are important hormones that affect the ovarian development of shrimp and crab, such as estradiol (E2), testosterone (T), and progesterone. Steroids can impact gonadal development and play a very important role in ovarian development and vitellogenesis. However, these hormones are restricted by a variety of environmental factors, such as temperature, light, salinity, and so on. In order to investigate the effect of salinity on hemolymph related hormones during mating and spawning of E. sinensis, the spawning salinity was set at 0, 2, 4, 6 and mating salinity set at 3, 6, 9, 12, 15, 18, 21. Five samples were collected from specimens in each salinity to analyze the contents of DHP, GTH, PG, E2, and testosterone in the hemolymph of female E. sinensis before and after mating and spawning under different mating and spawning salinities. The components were detected by ELISA at the wavelength of 450 nm using the kit double antibody sandwich method. Results revealed: (1) in fresh water, female crabs displayed no mating behavior. When the salinity was lower than 6, female crabs only mated without spawning. (2) There were no significant changes in PG, E2, or testosterone in the hemolymph of female crabs after mating in low salinity (2–6), and there was no significant difference between crabs at different salinities after mating (P > 0.05). (3) The contents of DHP, PG, E2, and testosterone in the hemolymph of female crabs initially decreased and then increased with salinity before spawning. After spawning, DHP, PG, and E2 in hemolymph initially increased and then decreased with increased salinity. When the salinity was 18, DHP, PG, E2, and testosterone in the hemolymph of the female crab after spawning decreased to the lowest level, and there was a significant difference between the before and after spawning results (P < 0.05). (4) At 6 salinity, the contents of DHP, PG, E2, and testosterone in the hemolymph of female crabs before spawning were the highest and the contents of DHP and PG decreased after spawning, while the contents of E2 and testosterone increased. However, there was only significant variation in the DHP from before spawning to after spawning (P < 0.05), and there was no significant difference in the other indexes (P > 0.05). The content of testosterone in the hemolymph initially decreased and then increased before and after spawning. This comprehensive study showed that salinity effects the five hormones in the hemolymph of female E. sinensis during the reproductive and breeding stage. Among them, the five hormones do not change significantly during the mating process of E. sinensis. DHP, GTH, and PG are involved in the oviposition of E. sinensis. The analyses of the changes in the related hormones in the hemolymph of female E. sinensis before and after mating and spawning at different salinities have identified changes in the neutral hormones. These results provide details on the reproductive regulation mechanism of E. sinensis and provided basic reference data for researching the reproductive biology of E. sinensis.

The glymphatic system is a system that promotes the exchange and flow of cerebrospinal fluid (CSF) -interstitial fluid (ISF) to maintain the balance of CSF-ISF, and rid the neuropil of toxic proteinaceous metabolites with astroglial water channel aquaporin-4 as the mediator. Increasing evidence has shown that the glymphatic system is strongly related to the pathological changes and outcomes of stroke. Available studies have found that the glymphatic system partially affects post-stroke cerebrospinal fluid circulation and cerebral edema. Different types of strokes include acute ischemic stroke, subarachnoid hemorrhage and intracerebral hemorrhage also have pathological changes in the glymphatic system. This review summarizes the structure and function of the glymphatic system, and the latest developments in its impact on pathological changes of different types of strokes, providing a new direction for the prevention and treatment of stroke.

This article takes the geological disasters of avalanches and landslides in the upper mountain of a mine in Guizhou Province as an example, and uses discrete and finite element numerical analysis methods to establish two-dimensional and three-dimensional numerical calculation models of slumped mass. The change process of the stability coefficient of the upper slope of the coal mine under the action of underground excavation is calculated, and the formation mechanism of the collapse body is analyzed from the aspects of displacement, stress and strain of the mountain instability. The research results show that the underground mining activities of coal mines under natural conditions have an impact on the stability of the upper mountain. When the local underground coal mining activities are close to the mountain, the mining activities have little effect on the stability of the mountain. However, when the mining activities are carried out in the lower part of the mountain, its influence on the stability of the mountain gradually increases, which shows that underground mining activities are one of the main factors leading to the occurrence of avalanche disasters in the upper mountain of a mine in Guizhou Province.

Objective To summarize and analyze the etiology and clinical features of the third nervepalsy(TNP). Methods and Results The clinical data of patients with TNP diagnosed from January to October 2019 were retrospectively analyzed. A total of 32 patients with TNP were included. There were 17 cases (53.12%) of acute onset and 15 cases (46.88%) of subacute onset. Monocular involvement was found in 30 cases (93.75%) and binocular involvement in 2 cases (6.25%). There were 10 cases (31.25%) with headache, and 8 cases(25%)with pupil involvement. Theetiology wasdiagnosed as microcirculation disorder (16cases,50%), non⁃specific inflammation (11cases,34.38%), posterior communication aneurysm (2 cases, 6.25%), midbrain infarction (1 case, 3.13%), brain stem demystification (1 case, 3.13%) and eosinophilia (1 case, 3.13% ). Improvement of circulation (microcirculation disorder and midbrain infarction), anti⁃inflammatory and suppressive inflammatory response (non⁃specific inflammation, brainstem demyelination and eosinophilia) or interventional therapy (posterior communication aneurysm) were performed. After treatment, 31 cases (96.88%) showed remission of symptoms and 1 case (3.13%) had poor prognosis. Conclusions Microcirculation disorder is the main cause of TNP, and intracranial aneurysm is the most dangerous cause. Eye pain and pupil involvement are not the specific symptoms of intracranial aneurysms. Relevant examinations can actively improve the determination of the cause and appropriate treatment. Most patients have a good prognosis. DOI：10.3969/j.issn.1672⁃6731.2020.08.016

Objective To explore the role and molecular mechanism of Neferine (Nef) on PC12 cells injury induced by Aβ1-42. Methods PC12 cells were divided into control group, model group(4 μg/mL Aβ1-42 cultured for 24 h) and low, medium and high-dose neferine intervention group. The PC12 cell viability was determined by MTT method and cell apoptosis was detected by flow cytometry. Protein expression of aquaporin4 (AQP4), Bcl-2 and Bax was analyzed by Western Blot, and miR-29a-3p, AQP4 mRNA were detected by qPCR. Biological information prediction and dual luciferase gene report analyzed the targeting relationship between miR-29a-3p and AQP4. miR-29a-3p, si-AQP4 were transfected into PC12 cells induced by Aβ1-42, or anti-miR-29a-3p was transfected into cells and performed high-dose Nef intervention to investigate the effects on cell survival and apoptosisin PC12 cells injury induced by Aβ1-42. Results Compared with the model group, the cell viability rate, Bcl-2 and miR-29a-3p expression of neferine group were significantly increased, and the cell apoptosis rate, Bax, AQP4 mRNA and protein of neferine group expression were significantly decreased (P＜0.05). AQP4 was the target gene of miR-29a-3p. Both over-expression of miR-29a-3p and inhibition of AQP4 expression significantly increased the viability rate of PC12 cells injury induced by Aβ1-42 and the expression level of Bcl-2, and decreased the apoptosis rate and Bax protein level. Inhibitiion of expression of miR-29a-3p reversed the promotion effect of Neferine on the survival of PC12 cell injury induced by Aβ1-42 and the level of Bcl-2 protein, as well as the inhibition effect of Neferine on the apoptosis rate and Bax protein expression. Conclusions Neferine inhibits PC12 cell injury induced by Aβ1-42, promotes cell survival and inhibits apoptosis by miR-29a-3p/AQP4.

Objective: To establish a new method for detection of red blood cell osmotic fragility by using flow cytometry., Methods: The hypotension salt solution of different concentrations (0.70 ml normal saline+0.3 ml deionized water, 0.60 ml normal saline+0.40 ml deionized water and 0.55 ml normal saline+0.45 ml deionized water) were prepared with normal saline and deionized water, in which the red blood cells were suspended, and the residual red blood cells were detected by flow cytometer., Results: There was no significant difference in percentage of residual red blood cells between different time points detected by flow cytometer in 3 different hypotonic salt solutions. The percentage of residual red blood cells in B+C+D+E+F+G detected time region was different among 3 NaCl dilution groups. The percentage of residual red blood cells in normal control was lower than that in hemoglobinopathy group. The percentage of residual red blood cells in hereditary spherocytosis (HS) group was obviously lower than that in hemoglobinopathy and normal control groups. The comparison of 3 different dilution concentrations found that the second concentration (0.60 ml normal saline+0.40 ml deionized water) is more suitable to screen HS by FC500 flow cytometer., Conclusion: The detection of red cell osmotic fragility by using flow cytometry is a simple, rapid, objective and economic way that can be an effective screening method for diagnose the HS.

Objective: To evaluate the effect of a comprehensive schistosomiasis control strategy based on buffalo removal in a lake and marshland region., Methods: A community intervention trial was carried out in seven pilot villages and seven control villages along Dongting Lake in Anxiang County, Hunan Province. Besides annual routine control measures such as synchronous chemotherapy, molluscicidal spray and health education, all buffaloes and sheep were killed or removed from the pilot areas in 2005, of which the effect was strengthened by other supporting measures such as replacing bovines by agricultural machines, isolating meadows and prohibiting pastures, supplying safe water, and building sanitary lavatories or methane pits. Schistosoma japonicum infection in humans or Oncomelania snails was observed and followed up to the spring of 2011., Results: Three years after the intervention, the infection rates in humans decreased to below 1% with no infected snails found outside the embankment in the pilot villages, but the infection rates still ranged between 2% and 3% in the control villages 4 years after the intervention. The comprehensive measures centered on buffalo removal exempted about 50% of the population from the infection in pilot villages., Conclusion: Buffalo removal is the key element of comprehensive control strategy which could accelerate the control process and promote the elimination of schistosomiasis in lake and marshland regions along the Yangtze River.