Transcriptomic and physiological analysis of atractylodes chinensis in response to drought stress reveals the putative genes related to sesquiterpenoid biosynthesis.

BACKGROUND: Atractylodes chinensis (DC) Koidz., a dicotyledonous and hypogeal germination species, is an important medicinal plant because its rhizome is enriched in sesquiterpenes. The development and production of A. chinensis are negatively affected by drought stress, especially at the seedling stage. Understanding the molecular mechanism of A. chinensis drought stress response plays an important role in ensuring medicinal plant production and quality. In this study, A. chinensis seedlings were subjected to drought stress treatment for 0 (control), 3 (D3), and 9 days (D9). For the control, the sample was watered every two days and collected on the second morning after watering. The integration of physiological and transcriptomic analyses was carried out to investigate the effects of drought stress on A. chinensis seedlings and to reveal the molecular mechanism of its drought stress response. RESULTS: The malondialdehyde, proline, soluble sugar, and crude protein contents and antioxidative enzyme (superoxide dismutase, peroxidase, and catalase) activity were significantly increased under drought stress compared with the control. Transcriptomic analysis indicated a total of 215,665 unigenes with an average length of 759.09 bp and an N50 of 1140 bp. A total of 29,449 differentially expressed genes (DEGs) were detected between the control and D3, and 14,538 DEGs were detected between the control and D9. Under drought stress, terpenoid backbone biosynthesis had the highest number of unigenes in the metabolism of terpenoids and polyketides. To identify candidate genes involved in the sesquiterpenoid and triterpenoid biosynthetic pathways, we observed 22 unigene-encoding enzymes in the terpenoid backbone biosynthetic pathway and 15 unigene-encoding enzymes in the sesquiterpenoid and triterpenoid biosynthetic pathways under drought stress. CONCLUSION: Our study provides transcriptome profiles and candidate genes involved in sesquiterpenoid and triterpenoid biosynthesis in A. chinensis in response to drought stress. Our results improve our understanding of how drought stress might affect sesquiterpenoid and triterpenoid biosynthetic pathways in A. chinensis.

Application of Network-Based PBL Model Combined with Role-Playing Method in Geriatric Nursing Teaching.

Objective: To evaluate the effectiveness of using a combination of problem-based learning (PBL) and role-playing methods in geriatric nursing education through online networks. Methods: The research objects of this paper were selected from nursing students, and the number of participants was 200. The research objects were selected from March 2019 to September 2021. The learning situation and related data of the above students were retrospectively analyzed. According to the teaching methods, the students were divided into groups. The students who received traditional teaching methods were included in the control group, with a total of 100 participants. The students who received network-based PBL mode combined with role-playing teaching were included in the observation group, with a total of 100 participants. The assessment results and learning effect evaluation of the two groups of students were compared, and the level of learning engagement and changes in critical thinking between the groups were compared. Results: The scores of basic theoretical knowledge, clinical practice skills, and clinical case analysis of students in the observation group were higher than those of the control group (P < .001). The evaluation index of nursing students' learning effects was analyzed. The proportions of enhancing teacher-student interaction, improving team cooperation ability, improving autonomous learning ability and learning interest, improving analysis and problem-solving ability, improving theory combined with practice ability, improving communication and expression ability, improving work self-confidence, improving knowledge and vision, improving literature retrieval and evaluation ability in the observation group were higher than that in the control group (P < .001). After the teaching work, the overall learning input score, cognitive input score, behavior input score, emotional input score, learning harvest score, and learning satisfaction score of students in the observation group were higher than those of the control group (P < .001). After teaching, the scores of finding the truth, open mind, analytical ability, systematic ability, critical thinking self-confidence, curiosity and cognitive maturity of the students in the observation group were higher than those in the control group (P < .001). Conclusion: The combined application of network-based PBL mode and role-playing method can significantly improve the teaching effects of geriatric nursing, with popularization value.

Ginsenoside Rk3 Inhibits the Extramedullary Infiltration of Acute Monocytic Leukemia Cell via miR-3677-5p/CXCL12 Axis.

Background: Acute monocytic leukemia belongs to type M5 of acute myeloid leukemia (AML) classified by FAB, which appears a high incidence of extramedullary infiltration (EMI) and poor prognosis. In this study, we observed the inhibitory effect of ginsenoside Rk3 on the EMI of monocytic leukemia cells and initially explored its related mechanism of targeting the miR-3677-5p/CXCL12 axis. Methods: The MTT assay and colony formation assay were used to detect the inhibitory effect of Rk3 on proliferation. Both cellular migration and invasion were observed by the Transwell assay. The expression levels of miR-3677-5p, CXCL12, and CXCR4 were detected by RT-qPCR and Western blot, as well as overexpression of miR-3677-5p by transfected with lentivirus and detection of a dual luciferase reporter gene. The expression of MMP2 and TIMP2 was detected by immunofluorescence. Results: Rk3 effectively inhibits the proliferation, migration, and invasion associated with EMI of leukemia. The leukemia cells of M5 patients with EMI showed low expression of miR-3677-5p but high expression of the mRNA of CXCL12 and CXCR4. Overexpression of miR-3677-5p or intervention of CXCL12 effectively inhibited the proliferation, migration, and invasion of SHI-1 cells. The luciferase assay showed that CXCL12 was the downstream target gene of miR-3677-5p. After overexpression of miR-3677-5p or intervention of CXCL12 in combination with Rk3, the inhibitory effect on the proliferation, migration, and invasion of SHI-1 cells was more obvious. Importantly, Rk3 significantly regulated the expression levels of miR-3677-5p, CXCL12, CXCR4, and EMI-related functional proteins including MMP2 and TIMP2. Overexpression of miR-3677-5p or intervention of CXCL12 also regulated the expression of MMP2 and TIMP2. Conclusions: The leukemia cells of M5 patients with EMI appeared to have low expression of miR-3677-5p and high expression of the mRNA of CXCL12 and CXCR4, which may be used as indicators of EMI and poor prognosis. Rk3 is effective in inhibiting the EMI of SHI-1 cells by targeting the miR-3677-5p/CXCL12 axis.

Comparative transcriptome analysis reveals sesquiterpenoid biosynthesis among 1-, 2- and 3-year old Atractylodes chinensis.

BACKGROUND: Atractylodes chinensis (DC.) Koidz is a well-known medicinal plant containing the major bioactive compound, atractylodin, a sesquiterpenoid. High-performance liquid chromatography (HPLC) analysis demonstrated that atractylodin was most abundant in 3-year old A. chinensis rhizome, compared with those from 1- and 2-year old rhizomes, however, the molecular mechanisms underlying accumulation of atractylodin in rhizomes are poorly understood. RESULTS: In this study, we characterized the transcriptomes from rhizomes of 1-, 2- and 3-year old (Y1, Y2 and Y3, respectively) A. chinensis, to identify differentially expressed genes (DEGs). We identified 240, 169 and 131 unigenes encoding the enzyme genes in the mevalonate (MVA), methylerythritol phosphate (MEP), sesquiterpenoid and triterpenoid biosynthetic pathways, respectively. To confirm the reliability of the RNA sequencing analysis, eleven key gene encoding factors involved in the sesquiterpenoid and triterpenoid biosynthetic pathway, as well as in pigment, amino acid, hormone and transcription factor functions, were selected for quantitative real time PCR (qRT-PCR) analysis. The results demonstrated similar expression patterns to those determined by RNA sequencing, with a Pearson's correlation coefficient of 0.9 between qRT-PCR and RNA-seq data. Differential gene expression analysis of rhizomes from different ages revealed 52 genes related to sesquiterpenoid and triterpenoid biosynthesis. Among these, seven DEGs were identified in Y1 vs Y2, Y1 vs Y3 and Y2 vs Y3, of which five encoded four key enzymes, squalene/phytoene synthase (SS), squalene-hopene cyclase (SHC), squalene epoxidase (SE) and dammarenediol II synthase (DS). These four enzymes directly related to squalene biosynthesis and subsequent catalytic action. To validate the result of these seven DEGs, qRT-PCR was performed and indicated most of them displayed lower relative expression in 3-year old rhizome, similar to transcriptomic analysis. CONCLUSION: The enzymes SS, SHC, SE and DS down-regulated expression in 3-year old rhizome. This data corresponded to the higher content of sesquiterpenoid in 3-year old rhizome, and confirmed by qRT-PCR. The results of comparative transcriptome analysis and identified key enzyme genes laid a solid foundation for investigation of production sesquiterpenoid in A. chinensis.

Utilization of domestic wastewater as a water source of Tetradesmusobliquus PF3 for the biological removal of nitric oxide.

The reduction of nitrogen oxide (DeNOx) from flue gas by microalgae is a promising technology that has attracted increasing attention. Because the water source is a major limitation of microalgae application in the DeNOx from flue gas, we investigated the feasibility of using domestic wastewater (WW) as a water source. As a result, a biomass accumulation rate of 0.27 ± 0.01 mg L-1 d-1 was achieved by Tetradesmusobliquus PF3 cultivated in WW for 8 d, and 30 mg L-1 of nitrate nitrogen was added to the WW to fulfill the nutrient requirements of the microalgae cells. The ammonium (NH4+) nitrogen present in WW exerted inhibitory effects on the removal of nitric oxide (NO), thereby leading to 8% decrease removal efficiency in comparison with that using clean water and nutrients (BG11 medium). However, these inhibitory effects disappeared following the exhaustion of NH4+ by T. obliquus PF3 after 1 d. To overcome the inhibition of NH4+ and to achieve a high NO removal efficiency, a strategy of connecting two reactors in series was presented. The removal efficiency of NO by the two series reactors reached up to 71.2 ± 2.9%, which was significantly higher than that obtained by a single reactor (43.1 ± 3.6%). In addition, 70.9 ± 4.8% of the supplied NO was fixed into microalgae cells in the two reactors, which was 1.75 times higher than that in the single reactor (40.6 ± 5.1%), thereby suggesting that connecting two reactors in series rendered effective recovery of NO from flue gas using WW as a water source. In this study, we provided an economically viable water source for the application of microalgae in the biological DeNOx from flue gases.

Fructus Psoraleae-Induced Severe Liver Injury and Treatment With Two Artificial Liver Support Systems: A Case Series Study.

To describe the clinical features and outcomes of patients with suspected Fructus Psoraleae (FP)-induced severe liver injury who underwent treatment with two artificial liver support systems (ALSSs). The cases of 12 patients with severe liver injury by FP were enrolled. We evaluated the tolerability of, and changes in biochemical parameters after treatment with plasma exchange combined with hemofiltration and double plasma molecular absorption system, and 6-month follow-up information were collected. The median age of the 12 patients was 60 years and nine (75%) patients were females. All patients had jaundice as the initial symptom. Two ALSS types were used to treat the patients. The group that underwent plasma exchange combined with hemofiltration showed remarkable improvements in ALT, AST, total bilirubin (TB), GGT and international normalized ratio levels (AST, TB, international normalized ratio, P < 0.01; ALT, GGT, P < 0.05), and the levels of AST, ALP, TB, and total bile acid decreased significantly in the double plasma molecular absorption system group after treatment (TB, P < 0.01; AST, ALP, total bile acid P < 0.05). During 6 months of follow-up, two patients died, two became chronic, and eight recovered to normal. FP can cause clinically severe liver injury, characterized by gastrointestinal symptoms and jaundice, which can lead to death or become chronic. Both ALSSs were safe and well tolerated in drug-induced liver injury patients. After ALSS treatment, the levels of biochemical indicators of liver function improved significantly, indicating that ALSS might be beneficial for patients with severe drug-induced liver injury.

The differences in bioaccumulation and effects between Se(IV) and Se(VI) in the topmouth gudgeon Pseudorasbora parva.

Selenium (Se) might be protective against oxidative stress at nutritional levels, but elevated Se concentrations in the diet has been revealed as the main culprit for the extinction of natural fish populations in Se-contaminated lakes. Though Se predominate as waterborne selenite (IV) and selenate (VI) in the water, the differences in bioaccumulation, effects (e.g., oxidative stress, antioxidants etc.) and molecular mechanisms between Se(IV) and Se(VI) have been relatively understudied in wild fish. In this study, the P. parva were exposed to waterborne Se (10, 200 and 1000 µg/L of Se(IV) or Se(VI)) and sampled at 4, 14 and 28 days. Bioaccumulation, tissue distributions of Se and following effects in different tissues were evaluated. The results showed that the levels of Se in the gills and intestine were significantly elevated with a seemingly concentration-dependent pattern in the Se(IV) treatment, with respectively 173.3% and 57.2% increase after 28 days of exposure, relative to that of Se(VI) treatment. Additionally, significant accumulation of Se was also observed in the muscle of Se(IV) treated fish. Se exposure increased the MDA levels in the brain and gills in the Se(IV) treatment, but less apparent in the Se(VI) treatment. Meanwhile, Se exposure lowered (at least 56%) the activity of GST in the gills, but increased the activity of AChE in the muscle (~69%) and brain (~50%) after 28 d. Most importantly, after 28 d of exposure, Se exposure caused significant decrease in GSH levels in the gills (at least 35%) and in all tissues examined at the highest test concentration. In general, the results showed that Se(IV) led to faster accumulation of Se than Se(VI) in P. parva, and the resulted lipid peroxidation was closely related to the levels of antioxidants, especially GSH. Our results suggest that the ecotoxicological effects of waterborne selenite and selenate differ in this freshwater species in the field.

Selenium accumulation and the effects on the liver of topmouth gudgeon Pseudorasbora parva exposed to dissolved inorganic selenium.

Selenite(IV) and selenate(VI) are the major forms of Se in aquatic ecosystem. In this study, Pseudorasbora parva were exposed to 10, 200 and 1000 µg L-1 selenite and selenate for 28 days. Selenium accumulation, antioxidant enzyme levels, glutathione concentrations, lipid peroxidation and histology were evaluated in livers following exposure. Our results showed that Se(IV) and Se(VI) caused different accumulation patterns in the liver, with a more rapid accumulation of Se with Se(IV) treatment. Both Se species increased hepatic lipid peroxidation after 14 and 28 d (~ 30%). Among the antioxidants examined, the activity of SOD (except day 28) and the cellular levels of GSH were induced by 72-137% at lower concentrations, while the activity of GST was at least 24% lower than that of the control at 200 and 1000 µg L-1 for both Se species at all sampling points. Both forms of Se reduced the hepatosomatic index at 1000 µg L-1 after 28 d. In addition, marked histopathological alterations (10-31%) were observed in the liver of P. parva after exposure to both Se species, with higher frequency in the Se(IV) exposed fish. Liver local necrosis was observed only in the liver of fish exposed to 1000 µg L-1 of Se(IV) (~ 20%). Our results suggest that the ecological impacts of dissolved Se in this freshwater species may also contribute to overall toxicity.

Natural light-micro aerobic condition for PSB wastewater treatment: a flexible, simple, and effective resource recovery wastewater treatment process.

Photosynthetic bacteria (PSB) have two sets of metabolic pathways. They can degrade pollutants through light metabolic under light-anaerobic or oxygen metabolic pathways under dark-aerobic conditions. Both metabolisms function under natural light-microaerobic condition, which demands less energy input. This work investigated the characteristics of PSB wastewater treatment process under that condition. Results showed that PSB had very strong adaptability to chemical oxygen demand (COD) concentration; with F/M of 5.2-248.5 mg-COD/mg-biomass, the biomass increased three times and COD removal reached above 91.5%. PSB had both advantages of oxygen metabolism in COD removal and light metabolism in resource recovery under natural light-microaerobic condition. For pollutants' degradation, COD, total organic carbon, nitrogen, and phosphorus removal reached 96.2%, 91.0%, 70.5%, and 92.7%, respectively. For resource recovery, 74.2% of C in wastewater was transformed into biomass. Especially, coexistence of light and oxygen promote N recovery ratio to 70.9%, higher than with the other two conditions. Further, 93.7% of N-removed was synthesized into biomass. Finally, CO2 emission reduced by 62.6% compared with the traditional process. PSB wastewater treatment under this condition is energy-saving, highly effective, and environment friendly, and can achieve pollution control and resource recovery.

Ameliorating Effects of Bacillus subtilis ANSB060 on Growth Performance, Antioxidant Functions, and Aflatoxin Residues in Ducks Fed Diets Contaminated with Aflatoxins.

Bacillus subtilis ANSB060 isolated from fish gut is very effective in detoxifying aflatoxins in feed and feed ingredients. The purpose of this research was to investigate the effects of B. subtilis ANSB060 on growth performance, body antioxidant functions, and aflatoxin residues in ducks fed moldy maize naturally contaminated with aflatoxins. A total of 1500 18-d-old male Cherry Valley ducks with similar body weight were randomly assigned to five treatments with six replicates of 50 ducks per repeat. The experiment design consisted of five dietary treatments labeled as C0 (basal diet containing 60% normal maize), M0 (basal diet containing 60% moldy maize contaminated with aflatoxins substituted for normal maize), M500, M1000, and M2000 (M0 +500, 1000 or 2000 g/t aflatoxin biodegradation preparation mainly consisted of B. subtilis ANSB060). The results showed that ducks fed 22.44 ± 2.46 µg/kg of AFB1 (M0) exhibited a decreasing tendency in average daily gain (ADG) and total superoxide dismutase (T-SOD) activity in serum, and T-SOD and glutathione peroxidase (GSH-Px) activities in the liver significantly decreased along with the appearance of AFB1 and AFM1 compared with those in Group C0. The supplementation of B. subtilis ANSB060 into aflatoxin-contaminated diets increased the ADG of ducks (p > 0.05), significantly improved antioxidant enzyme activities, and reduced aflatoxin accumulation in duck liver. In conclusion, Bacillus subtilis ANSB060 in diets showed an ameliorating effect to duck aflatoxicosis and may be a promising feed additive.

A New Degraded Sesquiterpene from the Twigs of Trigonostemon lutescens.

A new degraded sesquiterpene, tectoionol C (1), together with five known compounds wilsonol F (2), heterodendrin (3), epi-heterodendrin (4), 7-deoxogeayine (5), and 1H-indole-3-carboxylicacid, methyl ester (6), was isolated from the twigs of Trigonostemon lutescens. Their structures were determined by spectroscopic methods including 1D and 2D NMR techniques, as well as by comparison with published data.

A new tetranortriterpenoid from the roots of Atalantia buxifolia.

A new tetranortriterpenoid, named 6-deacetyl-severinolide, together with six known tetranortriterpenoids severinolide, acetyl-isoepiatalantin, 7-isovaleroylcycloepiatalantin, cycloepiatalantin, 7-isovaleroylcycloseverinolide, and atalantin, was isolated from the ethanol extract of the roots of Atalantia buxifolia collected in Hainan. Their structures were elucidated by spectroscopic methods including 1D and 2D NMR (HMQC, ¹H-¹H COSY, HMBC, and NOESY).

[Scavenging effect of Sarcandra glabra powder on radiation-induced reactive oxygen species in the parotid gland of miniature pigs].

OBJECTIVE: To investigate the effect of Sarcandra glabra in scavenging reactive oxygen species (ROS) produced by γ-ray irradiation in the parotid gland of miniature pigs. METHODS: Forty-five male miniature pigs were randomly divided into control group, radiation group and radiation plus medication group, and each group contained 3 parallel groups (subgroups a, b and c). From 1 week before exposure of the parotid gland region to 15 Gy γ-ray irradiation (which was not administered in the control group), the miniature pigs in radiation plus medication group were given Sarcandra glabra powder, while those in the other groups received an equal amount of saline. Bilateral parotid glands were taken and weighed on the days 10, 40 and 90 following the exposure in subgroups a, b, and c, respectively, and ROS content in the parotid glands were determined by enzyme-linked immunosorbent assay. RESULTS: The content of ROS was significantly lower in radiation plus medication group than in the radiation group (P<0.01). In the radiation plus medication group, the ROS content showed no significant difference between subgroups a and b or between subgroups a and c (P>0.01), but differed significantly between subgroups b and c (P<0.01). Sarcandra glabra showed a strong ROS-scavenging effect 10 days after the irradiation, and the ROS content was similar with that in the control group (P>0.01); at 40 and 90 days, the ROS-scavenging effect of Sarcandra glabra was still observable, but the ROS content was significantly higher in the irradiation plus medication group than in the control group (P<0.01). CONCLUSION: Sarcandra glabra displays a ROS-scavenging effect in the parotid gland of miniature pigs against irradiation, especially at 10 days following the exposure, which may serve as the main mechanism for the protective effect of Sarcandra glabra against radiation injury in the parotid gland.