Background: Medicinal plants rich in endophytic fungi are a significant source of natural lead compounds. Meroterpenoids, which are hybrid natural products originating from partially terpenoid pathways, exhibit impressive structural complexity and substantial potential as drug candidates. The structural diversity of meroterpenoids is largely attributed to the functional diversity of terpenoid cyclases, which generate a variety of terpenoid compounds with different ring systems. This enzymatic versatility underscores the biochemical potential of endophytic fungi and their invaluable role in drug discovery. Objective: The aim of the study was to investigate the role of endophytic fungi from Paris polyphylla var. yunnanensis in facilitating diverse cyclization modifications of meroditerpenoids through four terpene cyclases (TCs) from the Pyr4 family. Methods: This study utilized a recombinant strategy to successfully reconstruct four distinct TCs from endophytic fungi in the heterologous host, Aspergillus oryzae NSAR1. The structural characterization of the resulting secondary metabolites was performed using mass spectrometry and NMR techniques. Results: The substitution of TCs from the endophytes Aspergillus felis 0260 and Fusarium graminearum 1962 in Aspergillus oryzae through hydrophobic intermediates 1 and 2, led to the production of meroditerpenoids sartorypyrone C (3) and a new compound, 4′-methylchevalone E (4), respectively. This study demonstrates the critical role of endophytic fungi in enhancing structural diversity. Conclusions: These findings provide valuable insights into the compatibility of pathway combinations and the interchangeability of terpene cyclases derived from endophytic fungi in medicinal plants, which advanced the understanding of meroditerpenoid biosynthesis and highlighted the importance of endophytic fungi in drug discovery.

Background: Medicinal plants rich in endophytic fungi are a significant source of natural lead compounds. Meroterpenoids, which are hybrid natural products originating from partially terpenoid pathways, exhibit impressive structural complexity and substantial potential as drug candidates. The structural diversity of meroterpenoids is largely attributed to the functional diversity of terpenoid cyclases, which generate a variety of terpenoid compounds with different ring systems. This enzymatic versatility underscores the biochemical potential of endophytic fungi and their invaluable role in drug discovery. Objective: The aim of the study was to investigate the role of endophytic fungi from Paris polyphylla var. yunnanensis in facilitating diverse cyclization modifications of meroditerpenoids through four terpene cyclases (TCs) from the Pyr4 family. Methods: This study utilized a recombinant strategy to successfully reconstruct four distinct TCs from endophytic fungi in the heterologous host, Aspergillus oryzae NSAR1. The structural characterization of the resulting secondary metabolites was performed using mass spectrometry and NMR techniques. Results: The substitution of TCs from the endophytes Aspergillus felis 0260 and Fusarium graminearum 1962 in Aspergillus oryzae through hydrophobic intermediates 1 and 2, led to the production of meroditerpenoids sartorypyrone C (3) and a new compound, 4′-methylchevalone E (4), respectively. This study demonstrates the critical role of endophytic fungi in enhancing structural diversity. Conclusions: These findings provide valuable insights into the compatibility of pathway combinations and the interchangeability of terpene cyclases derived from endophytic fungi in medicinal plants, which advanced the understanding of meroditerpenoid biosynthesis and highlighted the importance of endophytic fungi in drug discovery.

Background: Medicinal plants rich in endophytic fungi are a significant source of natural lead compounds. Meroterpenoids, which are hybrid natural products originating from partially terpenoid pathways, exhibit impressive structural complexity and substantial potential as drug candidates. The structural diversity of meroterpenoids is largely attributed to the functional diversity of terpenoid cyclases, which generate a variety of terpenoid compounds with different ring systems. This enzymatic versatility underscores the biochemical potential of endophytic fungi and their invaluable role in drug discovery. Objective: The aim of the study was to investigate the role of endophytic fungi from Paris polyphylla var. yunnanensis in facilitating diverse cyclization modifications of meroditerpenoids through four terpene cyclases (TCs) from the Pyr4 family. Methods: This study utilized a recombinant strategy to successfully reconstruct four distinct TCs from endophytic fungi in the heterologous host, Aspergillus oryzae NSAR1. The structural characterization of the resulting secondary metabolites was performed using mass spectrometry and NMR techniques. Results: The substitution of TCs from the endophytes Aspergillus felis 0260 and Fusarium graminearum 1962 in Aspergillus oryzae through hydrophobic intermediates 1 and 2, led to the production of meroditerpenoids sartorypyrone C (3) and a new compound, 4′-methylchevalone E (4), respectively. This study demonstrates the critical role of endophytic fungi in enhancing structural diversity. Conclusions: These findings provide valuable insights into the compatibility of pathway combinations and the interchangeability of terpene cyclases derived from endophytic fungi in medicinal plants, which advanced the understanding of meroditerpenoid biosynthesis and highlighted the importance of endophytic fungi in drug discovery.

In order to meet the demand for high-quality medical professionals,it is an important goal of higher medical education to cultivate a compound medical professional degree postgraduate with both clinical and research capabilities.This study aims to investigate the current status of research ability training for medical postgraduate students in our university and analyze the main problems.Through designing and distributing questionnaires,feedback data from medical postgraduate students in our uni-versity were collected.The results show that some students lack research experience,have limited research output,and do not have the habit of independent literature reading.In response to the needs of training medical professional degree postgraduate students,this study proposes improvement suggestions.On one hand,optimizing the curriculum and using a closed-loop teaching mode with interactive discussions.On the other hand,strengthening mentor responsibilities and creating a good research atmos-phere.These measures can help improve the research ability of medical postgraduate students and better meet the demand for high-quality medical professionals.

In order to meet the demand for high-quality medical professionals,it is an important goal of higher medical education to cultivate a compound medical professional degree postgraduate with both clinical and research capabilities.This study aims to investigate the current status of research ability training for medical postgraduate students in our university and analyze the main problems.Through designing and distributing questionnaires,feedback data from medical postgraduate students in our uni-versity were collected.The results show that some students lack research experience,have limited research output,and do not have the habit of independent literature reading.In response to the needs of training medical professional degree postgraduate students,this study proposes improvement suggestions.On one hand,optimizing the curriculum and using a closed-loop teaching mode with interactive discussions.On the other hand,strengthening mentor responsibilities and creating a good research atmos-phere.These measures can help improve the research ability of medical postgraduate students and better meet the demand for high-quality medical professionals.

Objective To analyze the expression of insulin-like growth factor-1(IGF-1)in the serum of patients with pituitary adenomas and compare them according to different standards,investigating the expression of IGF-1 in pituitary adenoma and its clinical significance.Methods A total of 156 cases of pituitary adenomas admitted to the Second Affiliated Hospital of Kunming Medical Univer-sity from January 2019 to June 2021 were selected as the experimental group,and a total of 22healthy subjects during the same period were selected as the control group.To determinate the IGF-1 level by magnetic particle chemical luminescence immunoassay.The tumor di-ameter was obtained by combining the diameter measured on magnetic resonance imaging(MRI)with the diameter of postoperative tumor pathological specimen.The experimental group were divided into groups according to different clinical characteristics,and to compare the differences in IGF-1 levels between each subgroup and the control group.Results The levels of IGF-1 in patients with somatotroph adenoma,dual hormone and multihormone adenoma were higher than those in the control group and other types,and the differences were statistically significant(P＜0.05);the level of IGF-1 in giant adenoma patients was higher than those in the control group and other types,and the difference was statistically significant(P＜0.05);the level of IGF-1 in patients with invasive pituitary adenoma was higher than that in non-invasive patients and controls,and the difference was statistically significant(P＜0.05);Logistic regression a-nalysis showed that IGF-1 level and tumor diameter were risk factors for invasiveness of pituitary adenomas,the higher the IGF-1 level and the larger the tumor diameter,the higher the invasiveness risk;the level of IGF-1 in patients with pituitary adenoma within one month after surgery was significantly lower than that before surgery,and the difference was statistically significant(P＜0.05).Conclu-sion IGF-1 has a certain value in the diagnosis of different functional types of pituitary adenomas and the early invasiveness judgment of pituitary adenomas,and is expected to be used as a reliable indicator for postoperative follow-up.

Objective:To explore the pathogenesis of flunarizine-induced parkinsonism from gut-brain axis perspective.Methods:Thirty male C57BL/6 mice were randomly divided into control group and flunarizine group ( n=15). Mice in the control group were given 0.1 mL 50% polyethylene glycol 400+50% saline by gavage once/d for 2 weeks, while mice in the flunarizine group were given 6 mg/mL flunarizine+50% polyethylene glycol 400+50% saline by gavage at a daily dose of 30 mg/kg for 2 weeks. Body mass was recorded 1, 3, 5, 7, 10 and 14 d after drug administration, and motor function was assessed by rotarod test 14 d after drug administration; 16s RNA sequencing was performed in the feces to observe the intestinal flora; intestinal transit function was detected by Evans blue by gavage; and then, the mice were sacrificed and homogenate or frozen sections (brain and intestinal tissues) were prepared; dopamine-ergic neuron expression was detected by Western blotting; RT-qPCR was applied to detect the expressions of inflammatory factors in the substantia nigra, and immunofluorescent staining was used to detect the expressions of ZO-1 and Claudin-5 in the intestinal epithelial tissues. Results:Compared with the control group, the flunarizine group had lower body mass ratio 1, 3, 5, 7, 10 and 14 d after drug administration (ratio to body mass before drug administration). Compared with the control group, the flunarizine group had significantly shortened residence time in rod rotating and lower rotational speed when falling ( P<0.05). Compared with the control group, the flunarizine group had decreased tyrosine hydroxylase protein in the substantia nigra without significant difference ( P>0.05). Compared with the control group, the flunarizine group had significantly increased interleukin-6 and tumor necrosis factor-α in the substantia nigra (1.00±0.00 vs. 2.79±0.83; 1.00±0.00 vs. 3.39±1.37), significantly lower intestinal Evans blue propulsion rate (80.67%±4.51% vs. 50.67%±6.03%), and statistically decreased ZO-1 and Claudin-5 expressions in the colonic epithelial tissues (27.01±1.41 vs. 16.32±2.83; 37.00±2.80 vs. 24.52±2.12, P<0.05). Totally, 576 microorganisms were noted in both control group and flunarizine group, 744 in the control group alone, and 634 in the flunarizine group alone. The intestinal flora β diversity indices in the 2 groups were significantly different based on weighted Unifrac-principle coordinates analysis (PCoA, PCoA1: 39.88%; PCoA2: 30.69%). Compared with the control group, the microbial colony structure of mice in flunarizine group was dominated by phylum thick-walled bacteria and phylum warty microbacteria, and by families Muribaculaceae, Lachnospiraceae and Akkermansiaceae. Compared with the control group, the flunarizine group had significantly decreased relative abundance of Ackermannia spp. and Lactobacillus spp. in the intestinal flora ( P<0.05). Conclusion:Flunarizine may contribute to the pathogenesis of DIP by causing structural disturbances in the intestinal flora and inducing neuroinflammation based on the gut-brain axis.

The study adopted muscle injection of pVAX1-SP-GHRH(1-44)expression plasmid and electrostimulation to determine its effects on mouse growth and sow production performance.One hundred and fifty four-week-old C57 BL/6 female mice were randomly divided into 6 groups of 5 replicates each.Muscle single-injection followed by electrostimulation was performed.The con-trol group received an empty plasmid injection(80 μg/kg),while the treatment groups received pVAX1-SP-GHRH(1-44)plasmid injections(20,40,80,120,160 μg/kg).Twenty healthy preg-nant sows were randomly divided into 2 groups,each with 10 sows.Electrostimulation treatment was applied to the semimembranosus muscle of the pregnant sows after a single injection.The con-trol group received physiological saline injection,while the plasmid group received a 2 mg pVAX1-SP-GHRH(1-44)expression plasmid injection.Mouse weight,feed intake,and serum GHRH and IGF-1 levels were measured at days 0,7,14,21,and 28 after injection.Pregnant sows were bled via the tail vein at days 0,14,28,and 42 after injection,and their serum was separated to measure serum GHRH and IGF-1 levels.The birth weight,placental weight,number of piglets born,number of healthy piglets,number of weak piglets,number of deformed piglets,number of stillborn piglets,and number of mummified piglets were recorded at day 14.The mouse study re-sults showed that muscle injection of pVAX1-SP-GHRH(1-44)plasmid followed by electrostim-ulation could promote mouse feeding and increase weight gain(P＜0.05),significantly increase mouse serum GHRH and IGF-1 levels(P＜0.05),and maintain its effects until day 21.The results of the pregnant sow study showed that the average birth weight of the piglets in the plasmid group was significantly increased(P＜0.01),and the placenta weight was significantly increased(P＜0.05).The serum GHRH and IGF-1 concentrations in the plasmid group sows were significantly increased(P＜0.01).The study results showed that muscle injection of pVAX1-SP-GHRH(1-44)expression plasmid followed by electrostimulation could promote mouse feeding and increase weight gain,and also significantly improve the average birth weight and placental weight of the piglets in pregnant sows.