Silicon composition and stoichiometric ratios with other nutrients in the lower Minjiang River, Southeast China.

Over the past decades, rivers have delivered imbalanced nutrient loads to coastal marine ecosystems due to human activities, which leads to serious regional or global eutrophication problems. The Minjiang River is heavily influenced by human activities. To understand the changing characteristics of nutrient transport ratios in the Minjiang River waters, we measured the seasonal variations of carbon, nitrogen, phosphorus and silicon nutrients in the lower surface waters of the Minjiang River between July 2019 and July 2020. The results showed that the annual average contents of dissolved silicon (DSi), lithogenic silicon (LSi) and biogenic silicon (BSi) in the surface waters of the lower Minjiang River were 5.30, 4.58 and 2.37 mg·L-1, respectively. There were large seasonal differences among these parameters, with higher content of DSi than LSi and BSi in summer, higher content of DSi than BSi and LSi in autumn and higher content of LSi than DSi and BSi in winter. The proportions of DSi in total silicon tended to decrease gradually from land to sea, while the proportion of BSi was on the contrary. In term of stoichiometric ratios, the Minjiang River mostly presented carbon or phosphorus limitation and was unlimited by silicon or nitrogen. About 1.03×1010 mol DSi and 0.46 ×1010 mol BSi were delivered via the Minjiang River to the ocean yearly, showing a decreasing trend year by year. Based on the data in recent years, the nutrient loads of carbon, nitrogen, and phosphorus transported by Minjiang River showed an increasing trend. The imbalanced nutrient loads may lead to changes in the structure and function of the river, estuary, and offshore ecosystems. The study of nutrient stoichiometric ratios can provide a theoretical basis for solving the problems in structural balance of nutrients and eutrophication in Minjiang River estuary and adjacent marine waters.

Mechanisms of Traditional Chinese Medicine Bushenantai granules in promoting angiogenesis at the maternal-fetal interface of recurrent spontaneous abortion mice.

OBJECTIVE: To assess the effects of Bushenantai (BSAT) granule() on angiogenesis-related factors [E2, P, and vascular endothelial growth factor (VEGF)] at the maternal-fetal interface of recurrent spontaneous abortion (RSA) mice, and to evaluate the role of BSAT in promoting angiogenesis at the maternal-fetal interface by influencing the expression of sex hormones, and VEGF. METHODS: A mouse model with normal pregnancy and another with Clark's classic RSA were established. The RSA mice were randomly assigned to six groups: normal, model, progesterone, high-doseBSAT granule (BSAT-H), medium-dose-BSAT granule (BSAT-M), and low-dose-BSAT granule (BSAT-L) (n = 10 for each group). The embryo loss rate and the histopathological changes in the decidual tissues were measured. Serum levels of estrogen (E2), progesterone (P), and VEGF were detected by enzyme-linked immunosorbent assay. The mRNA and protein expressions of estradiol receptor (ER), progesterone receptor (PR), VEGF, and vascular endothelial growth factor receptor 2 (VEGFR2) in the decidual tissues were identified by immunohistochemistry, Western blotting, and quantitative reverse transcription polymerase chain reaction. RESULTS: The embryo loss rate in all groups that received BSAT treatment was reduced, while the number of blood vessels at decidual tissues was increased. The serum levels of E2, P and VEGF were elevated, and the mRNA and protein expressions of ER, PR, VEGF, and VEGFR2 in the decidual tissues were enhanced. CONCLUSION: BSAT can improve angiogenesis at the maternal-fetal interface and reduce the embryo loss rate, which may be associated with its ability to increase the serum levels of estrogen, progesterone, and VEGF, in addition to up-regulation of mRNA and protein expression of ER, PR, VEGF, and VEGFR2 in the decidual tissue.

De novo assembly and characterization of the Welsh onion (Allium fistulosum L.) transcriptome using Illumina technology.

Welsh onion (Allium fistulosum L.) has long been cultivated as a vegetable and spice for its flavor and aroma. However, transcriptomic and genomic data for A. fistulosum remain scarce. The goal of this study was to generate transcript sequences for functional genomic analyses, and identify genes potentially involved in sulfur, selenium, and vitamin metabolism. In total, 53,378,674 high-quality reads were generated, and de novo assembly resulted in 103,286 contigs and 53,837 unigenes. The average unigene length was 619 bp with an N50 of 832 bp. Similarity searches revealed that 36,155 sequences were similar to those of known proteins in public databases. Of these, 35,250 unigenes sequences were significantly similar to sequences in the NCBI non-redundant protein database and 22,804 were annotated in the Swiss-Prot database. Additionally, 13,125 and 26,660 unigenes were annotated in the Cluster of Orthologous Group and Gene Ontology databases, respectively. A total of 20,680 unigenes were classified into 128 pathways via functional annotation against the Kyoto Encyclopedia of Genes and Genomes pathway database. Key enzymes involved in sulfur and selenium metabolism were also identified. Additionally, our transcriptome revealed a number of unigenes encoding important enzymes involved in vitamin metabolism. We also identified 2014 simple sequence repeats in 1892 unigenes. This transcriptome analysis provides valuable information to further our understanding of the molecular mechanisms regulating the biosynthesis of organic sulfur compounds. The detected simple sequence repeats may facilitate marker-assisted selection in Welsh onion breeding experiments.

[Effect of cadmium stress on physiological characteristics of garlic seedlings and the alleviation effects of exogenous calcium].

In the experiment, the effects of exogenous cadmium (Cd2+) and calcium (Ca2+) in nutrient solution on growth, photosynthetic characteristics, enzymes activities, main mineral elements absorption of garlic seedlings were studied. The results showed that cadmium could obviously inhibit the growth of garlic seedlings, decrease the pigment contents and photosynthetic parameters (P(n), E, g(s)) of leaves, reduced the enzymes (SOD, POD, CAT) activities and increase the MDA content of leaves, and also could reduce the N, P, K, Ca, Mg contents and increase the Cd content of roots. The growth was promoted after adding exogenous calcium to garlic seedlings under cadmium stress, which reflected that the morphological indexes were increased at first and then decreased with the increase of exogenous calcium concentrations, and were maximized when the exogenous calcium was 2 or 3 mmol x L(-1). At the same time, the pigment contents and photosynthetic parameters (P(n), E, g(s)) of leaves showed a similar tendency with the morphological indexes, and they were the highest when the exogenous calcium was 2 or 3 mmol x L(-1). In addition, adding exogenous calcium to garlic seedlings under cadmium stress enhanced the enzymes (SOD, POD, CAT) activities and decreased the MDA content of leaves, also added the N, P, K, Ca, Mg contents and reduced the Cd content of roots, and the effect was best when the exogenous calcium concentration was 2 or 3 mmol x L(-1).

[Prophylactic immunization of dangguibuxue decoction against Cryptosporidium infection in immune suppressed mice].

OBJECTIVE: To explore the prophylaxis of dangguibuxue decoction, a traditional Chinese medicine made from Angelica sinensis and Radix astragalus, on immunosuppressed mice infected by Cryptosporidium parvum. METHODS: 48 BALB/c mice were randomly divided into 4 groups: normal control (A), immunosuppressed control (B), high dose (C), and low dose (D). Mice in groups B, C and D were intragastrically administered with dexamethasone (DXM) for 8 days, and in the same time mice in groups C and D were given high dose (2 g/kg) and low dose (1 g/kg) dangguibuxue decoction respectively. On the ninth day all mice in groups B, C and D were orally inoculated by 1 x 10(6) oocysts of C. parvum. The amount of oocysts in feces was examined daily since being infected. 11 days after infection, the subset of T lymphocytes in peripheral blood was analyzed with flow cytometry, sIL-2R in serum and sIgA of intestinal fluid were detected by ELISA. Pathological change of duodenum and jejunum was observed microscopically. RESULTS: Compared with the immuno-suppressed control group, there were less oocysts in feces (35.0 +/- 4.21) (P < 0.01) and lighter injury in the intestinal mucosa in mice of the high dose dangguibuxue decoction group. Both the number of CD4+ T lymphocytes (47.483 +/- 4.082) and the ratio of CD4+/CD8+ (2.271 +/- 0.378) increased, sIgA [(320.19 +/- 1.94) ng/ml] in the intestinal fluid elevated and sIL-2R [(321.34 +/- 6.66) ng/ml] in peripheral blood decreased in the high dose group, with a significant difference in comparison to the immunosuppressed group (P < 0.01). All the above-mentioned indices in low dose dangguibuxue decoction group showed no significant difference with the immunosuppressed control group (P > 0.05). CONCLUSION: Administration of high dose dangguibuxue decoction plays a role of prophylaxis on the infection of C. parvum in immunosuppressed mice through improving the immune status.