Pyran- and furanocoumarins are key representatives of tetrahydropyrans and tetrahydrofurans, respectively, exhibiting diverse physiological and medical bioactivities. However, the biosynthetic mechanisms for their core structures remain poorly understood. Here we combined multiomics analyses of biosynthetic enzymes in Peucedanum praeruptorum and in vitro functional verification and identified two types of key enzymes critical for pyran and furan ring biosynthesis in plants. These included three distinct P. praeruptorum prenyltransferases (PpPT1-3) responsible for the prenylation of the simple coumarin skeleton 7 into linear or angular precursors, and two novel CYP450 cyclases (PpDC and PpOC) crucial for the cyclization of the linear/angular precursors into either tetrahydropyran or tetrahydrofuran scaffolds. Biochemical analyses of cyclases indicated that acid/base-assisted epoxide ring opening contributed to the enzyme-catalyzed tetrahydropyran and tetrahydrofuran ring refactoring. The possible acid/base-assisted catalytic mechanisms of the identified cyclases were theoretically investigated and assessed using site-specific mutagenesis. We identified two possible acidic amino acids Glu303 in PpDC and Asp301 in PpOC as vital in the catalytic process. This study provides new enzymatic tools in the epoxide formation/epoxide-opening mediated cascade reaction and exemplifies how plants become chemically diverse in terms of enzyme function and catalytic process.

BACKGROUND:Anterior cruciate ligament injury tends to lead to secondary meniscus injury and osteoarthritis.At present,there are few studies on the mechanics of meniscus and articular cartilage injury caused by anterior cruciate ligament injury. OBJECTIVE:To study the effect of partial rupture of the anterior cruciate ligament on the stress of medial and lateral meniscus and articular cartilage of knee joint by finite element analysis. METHODS:The CT and MRI images of the knee joint of a healthy volunteer were selected,and the scan data were imported into Mimics,Geomagic and SolidWorks software.After registration and fusion,four kinds of three-dimensional knee joint models were established:models of intact anterior cruciate ligament,rupture of the posterior external tract of anterior cruciate ligament,rupture of the anterior internal tract of anterior cruciate ligament,and absence of anterior cruciate ligament.Finally,data were imported into Ansys software to apply four different modes of loads to the knee joint:Longitudinal loads of 750 N were applied to the top of the femur;longitudinal load of 750 N to the top of the femur and forward thrust of 134 N behind tibia;a longitudinal load of 750 N and a varus moment of 10 Nm were applied to the top of the femur to simulate genu varus;750 N longitudinal load and 4 Nm internal rotation moment were applied to the proximal end of the femur to simulate knee internal rotation.The finite element analysis of biomechanical stress changes of the meniscus and articular cartilage of the knee joint was carried out. RESULTS AND CONCLUSION:(1)In the straight position of the knee joint,when the anterior medial tract of the anterior cruciate ligament was broken and the anterior cruciate ligament was missing under longitudinal loads of 750 N at the top of the femur,the total stress and peak value of meniscus increased significantly,but the stress distribution of the meniscus and the stress of articular cartilage did not change significantly.In longitudinal load of 750 N to the top of the femur and forward thrust of 134 N behind tibia,the fracture of the anterior internal tract of the anterior cruciate ligament increased the tibia forward,the compressive stress of posterior angle of the meniscus increased,and the stress of the articular cartilage did not change significantly.During simulating genu varus,the posterior angular stress of the lateral meniscus decreased,the stress of the medial meniscus increased,and the stress of articular cartilage slightly decreased when anterior cruciate ligament injuries were complete.When the anterior internal tract of the anterior cruciate ligament was broken or absent under knee internal rotation,the equivalent stress peak value of femoral cartilage and tibia cartilage shifted from medial cartilage to lateral cartilage,and the stress peak value of meniscus increased significantly.At this time,the anterior internal tract of the anterior cruciate ligament played a leading role in the rotational stability of the knee joint.(2)These results indicate that the risk of secondary meniscus injury in patients with anterior and medial anterior cruciate ligament band rupture was much higher than that in patients with posterior and external anterior cruciate ligament band rupture when the knee was in the upright standing position,varus and pronation,and there was no significant difference in the impact on articular cartilage.

Objective To investigate the levels of soluble tyrosine kinase-1(sFlt-1)and chemokine C-C ligand 3(CCL3)in serum of patients with coronary heart disease(CHD)and their correlation with the severity of the disease.Methods A total of 230 elderly CHD patients admitted to the De-partment of Cardiovascular Medicine of Xinxiang Central Hospital from November 2020 to No-vember 2022 were collected as the study subjects(CHD group),and according to their Gensini score,they were divided into mild(n=89),moderate(n=95),and severe(n=46)CHD sub-groups.Another 230 healthy individuals who taking physical examination during the same period served as the control group.ELISA was applied to measure serum levels of sFlt-1 and CCL3.ROC curve was plotted to analyze the diagnostic values of serum sFlt-1 and CCL3 levels for CHD.Pear-son correlation analysis was employed to analyze the relationship between serum sFlt-1 and CCL3 levels and the CHD severity.Results The serum levels of sFlt-1 and CCL3 were obviously higher in the CHD group than the control group(121.71±29.80 ng/L vs 98.70±17.57 ng/L,18.22± 5.41 ng/L vs 13.68±3.89 ng/L,P＜0.01).ROC curve analysis showed that the AUC value of the two indicators combined together was significantly greater than that of them alone in diagnosis of CHD(0.886 vs 0.791,0.775,P＜0.01).The serum levels of sFlt-1 and CCL3 were increased along with the severity of the disease and Gensini score when the levels and the score were compared among the mild,moderate and severe subgroups(P＜0.05).Pearson correlation analysis indicated that the serum levels of sFlt-1 and CCL3 were positively correlated with the Gensini score(r=0.420,r=0.479,P＜0.01).Conclusion The levels of serum sFlt-1 and CCL3 are obviously ele-vated in CHD patients,and closely associated with the severity of coronary lesions.

There are a variety of post-transcriptional modifications in mRNA, which regulate the stability, splicing, translation, transport and other processes of mRNA, followed by affecting cell development, body immunity, learning and cognition and other important physiological functions. m⁶A modification is one of the most abundant post-transcriptional modifications widely existing in mRNA, regulating the metabolic activities of RNA and affecting gene expression. m⁶A modified homeostasis is critical for the development and maintenance of the nervous system. In recent years, m⁶A modification has been found in neurodegenerative diseases, mental diseases and brain tumors. This review summarizes the role of m⁶A methylation modification in the development, function and related diseases of the central nervous system in recent years, providing potential clinical therapeutic targets for neurological diseases.
Methylation ; Central Nervous System/metabolism* ; RNA, Messenger/metabolism* ; RNA

Objective:To investigate the expression profile of IL-36 family members in patients with coronary atherosclerotic heart disease (CAHD) and to assess the regulatory effects of exogenous IL-36 on CD8 + T cell function in CAHD patients. Methods:Twenty controls and 82 CAHD patients including 31 with stable angina pectoris (SAP), 27 with unstable angina pectoris (UAP) and 24 with acute myocardial infarction (AMI) were enrolled in this study. Anti-coagulant peripheral blood samples were collected. Plasma and peripheral blood mononuclear cells were isolated. The levels of IL-36α, IL-36β, IL-36γ and IL-36 receptor antagonist (IL-36RA) in plasma were measured by ELISA. CD8 + T cells were enriched. The expression of IL-36 receptor subunits at mRNA level was semi-quantified by real time PCR. Flow cytometry was used to detect the expression of programmed death-1 (PD-1), cytotoxic T lymphocytes associated protein-4(CTLA-4) and lymphocyte-activation gene-3 (LAG-3) in CD8 + T cells. Levels of periforin, granzyme B, granulysin, IFN-γ and TNF-α in the culture supernatants of CD8 + T cells were measured by ELISA. Purified CD8 + T cells from controls and AMI patients were stimulated with recombinant human IL-36RA. Changes in the expression of immune checkpoint molecules and the secretion of cytotoxic molecules and cytokines after IL-36RA stimulation were analyzed. One-way analysis of variance or paired t-test was used for statistical analysis. Results:There were no significant differences in plasma IL-36α, IL-36β or IL-36γ level between the control, SAP, UAP and AMI groups ( P>0.05). Plasma IL-36RA level was significantly down-regulated in the AMI group as compared with that in the control, SAP and UAP groups[(1 159.57±297.83) pg/ml vs (1 773.47±754.29) pg/ml, (1 600.12±740.48) pg/ml and (1 578.72±720.42) pg/ml; P<0.05]. The expression of IL-1 receptor 6 (IL-1R6) and IL-1 receptor accessory protein (IL-1RAcP) at mRNA level, the expression of PD-1 and CTLA-4, and the secretion of IFN-γ and TNF-α by CD8 + T cells showed no significant differences between the four groups ( P>0.05). Periforin, granzyme B and granulysin levels secreted by CD8 + T cells of the AMI group were significantly higherthan those of the control, SAP and UAP groups ( P<0.05). In the control group, recombinant human IL-36RA stimulation did not affect the expression of immune checkpoint molecule or the secretion of cytotoxic molecules and cytokines by CD8 + T cells ( P>0.05). In the AMI group, the percentage of PD-1 + CD8 + T cells increased after recombinant human IL-36RA stimulation ( P=0.033), but no significant change in the percentage of CTLA-4 + CD8 + T cells was observed ( P=0.288). Moreover, recombinant human IL-36RA stimulation suppressed the CD8 + T cells of AMI patients to secrete periforin, granzyme B and granulysin ( P<0.05), but not affect the secretion of IFN-γ and TNF-α ( P>0.05). Conclusions:The reduced IL-36RA level in AMI patients might induce the enhancement of CD8 + T cell activity by promoting CD8 + T cells to secrete cytotoxic molecules, which was involved in the immunopathogenesis of AMI.

Background The mechanisms of silicon dioxide (SiO₂)-induced inflammation and cell injury in pulmonary macrophages are not fully characterized. Objective To investigate the potential roles of inhibition of toll-like receptor 4 (TLR4)/nuclear factor-kappa B (NF-κB) signaling in inflammation and macrophage polarization in mouse Raw264.7 cells in response to SiO₂ stimulation. Methods Sixteen 6- to 8-week-old C57BL/6 mice, half male and half female, were intratracheally instilled with 50 µL of SiO₂ (50 mg·mL⁻¹ in saline) or normal saline via oropharyngeal route, and the lungs of mice were harvested at 14 d and 28 d post the first challenge of SiO₂. HE staining of mouse lung was used for histopathological analysis. The expressions of TLR4 signaling-related proteins were detected by Western blotting (WB) and immunofluorescent (IF) assay, including TLR4, myeloid differentiation factor 88 (Myd88), and TNF receptor associated factor 6 (TRAF6). Raw264.7 cells were stimulated with SiO₂ (100 μg·cm²) for 12 h in absence or presence of TLR4 inhibitor M62812 for 13 h before the culture supernatants and cell lysates were harvested for analysis. The expressions of key components of TLR4 signaling cascade including TLR4, Myd88, and phosphorylated nuclear factor-kappa B P65 (P-NF-κB P65), P-1NF-kappa-B inhibitor α (P-1κbα), tumor necrosis factor-α (TNF-α), and interleukin 6 (IL-6), M1 phenotype markers inducible nitric oxide synthase (iNOS) and cluster of differentiation 86 (CD86), as well as M2 phenotype arginase-1 (Arg-1) were accessed by WB and IF. The expressions of inflammation factors IL-6 and TNF-α in supernatants were determined by enzyme-linked immunosorbent assay (ELISA). Results After SiO₂ intratracheal instillation for 14 d, the HE staining results showed obvious fibrotic nodules in the lung tissues of mice. The results of WB analysis revealed more abundant TLR4, Myd88, and TRAF6 in the silicosis mouse lung samples than in the controls. The results of IF assay showed an increased abundance of TLR4 and Myd88 proteins in the lung samples of silicosis mice at 14 d post the silica challenge, compared to the controls, indicating TLR4 signaling activation. As seen in the in vitro experiment, significant upregulations after the exposure to 100 μg·cm² SiO₂ were observed in TLR4 and P-1κbα at 6, 12, and 24 h (P<0.05); Myd88 at 12 and 24 h (P <0.05); and P-NF-κB P65 at 12 h (P<0.05). The inhibitor significantly suppressed the expressions of TLR4, Myd88, TRAF6, P-NF-κB P65, TNF-α, and IL-6 in Raw264.7 cells. In addition, the SiO₂-induced M1 phenotype marker iNOS was significantly suppressed, but the M2 phenotype marker Arg-1 was increased in the Raw264.7 cells. Conclusion The inhibition of TLR4/NF-κB signaling could result in a reduction of the inflammation response and the transition of M1 toward M2 phenotypes of macrophages in response to SiO₂ challenge.

Objective:To investigate the clinical effect of medial plantar flap combined with free groin flap in the reconstruction of heel defect.Methods:The patients with heel skin and soft tissue defects admitted to the Department of Burns & Plastic and Hand & Foot Surgery of Yulin No.2 Hospital from October 2015 to December 2020 were retrospectively analyzed. After emergency debridement, a plantar medial island flap was used to repair the foot heel defect, a free groin flap was used to repair the medial plantar donor site, and the groin donor site was closed primarily. Postoperatively routine anti-infection, spasmolysis, anticoagulation, expanding treatment were performed after the procedure. The blood supply, survival of the flap, and the healing of the donor area of the flap were observed. The shape and function of the heel were observed in follow-up.Results:Eight patients were enrolled, including 7 males and 1 female, aged from 20 to 71 years, with an average of 32.2 years. There were 5 cases of heel trauma, 1 case of heel squamous cell carcinoma, 1 case of heel frostbite, and 1 case of heel ulcer. The wound area of the heel was 4 cm×3 cm-7 cm×6 cm. The surgical procedure was smooth, and the incision range of the heel island flap and groin flap was 0.5-1.0 cm larger than that of the heel wound. All 8 patients had primary healing after the operation. Follow-up for 3-12 months showed that all patients were satisfied with heel shape, sensory function and walking function. There was no depression, scar hyperplasia, and contracture in the medial plantar donor area, and no local skin ulcer. There is only a linear scar in the groin donor area.Conclusions:Medial plantar island flap combined with a free groin flap can repair the defect of the heel, and the affected foot has good healing, certain sensory function, and satisfactory curative effect.

Objective:To investigate the clinical effect of medial plantar flap combined with free groin flap in the reconstruction of heel defect.Methods:The patients with heel skin and soft tissue defects admitted to the Department of Burns & Plastic and Hand & Foot Surgery of Yulin No.2 Hospital from October 2015 to December 2020 were retrospectively analyzed. After emergency debridement, a plantar medial island flap was used to repair the foot heel defect, a free groin flap was used to repair the medial plantar donor site, and the groin donor site was closed primarily. Postoperatively routine anti-infection, spasmolysis, anticoagulation, expanding treatment were performed after the procedure. The blood supply, survival of the flap, and the healing of the donor area of the flap were observed. The shape and function of the heel were observed in follow-up.Results:Eight patients were enrolled, including 7 males and 1 female, aged from 20 to 71 years, with an average of 32.2 years. There were 5 cases of heel trauma, 1 case of heel squamous cell carcinoma, 1 case of heel frostbite, and 1 case of heel ulcer. The wound area of the heel was 4 cm×3 cm-7 cm×6 cm. The surgical procedure was smooth, and the incision range of the heel island flap and groin flap was 0.5-1.0 cm larger than that of the heel wound. All 8 patients had primary healing after the operation. Follow-up for 3-12 months showed that all patients were satisfied with heel shape, sensory function and walking function. There was no depression, scar hyperplasia, and contracture in the medial plantar donor area, and no local skin ulcer. There is only a linear scar in the groin donor area.Conclusions:Medial plantar island flap combined with a free groin flap can repair the defect of the heel, and the affected foot has good healing, certain sensory function, and satisfactory curative effect.

OBJECTIVE: To investigate the application value of whole exome sequencing technology in fetuses with congenital structural abnormalities. METHODS: The chromosomal abnormalities of 1147 families were analyzed. According to the follow-up results, the data of fetuses with new phenotypes in late pregnancy or after birth were reanalyzed. Subgroups were divided according to the organs involved and whether single malformation or not. The gene regulatory network map was drawn by using string database and Cytoscape software. Fisher exact probability method was used to compare the difference of the diagnostic rate of pathogenic genes among the groups. RESULTS: A total of 160 fetal cases received positive molecular diagnosed, involving 178 variant sites of 125 pathogenic genes, including 8 cases (4.9%, 8/163) by data reanalysis, and the overall positive diagnosis rate was 13.9%. Diagnostic rate was highest in the group of skeletal malformation (31.5%, 39/124) and lowest in that with thoracic malformation (0, 0/32). The gene clusters of fetal edema and intrauterine growth restriction were independent, and were not associated with the major structural malformations. The probability of each parent carrying the same recessive gene variant was 0.03 (39/1146) and 0.08 (4/53) with positive family history. CONCLUSION For fetuses with congenital structural abnormalities that are negative for conventional genetic tests, 13.9% of phenotypic associated pathogenic/likely pathogenic genetic variants can be detected by whole exome sequencing technology. Its application value for prenatal diagnosis varies in fetus with different organs involved. Reanalysis of sequencing data for cases with new phenotypes in late pregnancy or after birth can further improve the molecular diagnosis rate. Further investigations are needed to explore the related genetic mechanisms.
Female ; Fetal Diseases ; Fetus/diagnostic imaging* ; Humans ; Pregnancy ; Prenatal Diagnosis ; Technology ; Ultrasonography, Prenatal ; Whole Exome Sequencing

Objective:To investigate the effect of a breathing pattern intervention (RPI) on the oral feeding of pre-term infants with suck-swallow-breath (SSwB) coordination disorder.Methods:Sixty pre-term infants with SSwB coordination disorder were divided into an observation group ( n=30) and a control group ( n=30) using a random number table. Both groups were given routine feeding training, including oral exercise intervention, non-nutritive sucking training, and swallowing induction training during nursing, while the observation group was additionally provided with 15 minutes of breathing pattern training once a day, including breathing pattern observation, resistive breathing training prior to eating and passive breathing pattern intervention during eating. Before and after the 7-day intervention, the Pre-term Infant Oral Feeding Readiness Assessment (PIOFRA) was used to evaluate each subject′s oral feeding ability. Rate of transfer (RT), proficiency (PRO), minimum oxygen partial pressure (SaO 2) and SaO 2 fluctuations were also recorded during the feeding process. Results:After 1 week of the intervention, significant improvement was observed in both groups. In the observation group the average RT (2.76±0.36ml/min), PRO, minimum SaO 2, the number of SaO 2 fluctuations, and PIOFRA score (33.28±0.58) were all significantly better than the control group′s averages. Conclusion:Breathing pattern intervention based on routine feeding training can enhance breathing coordination during swallowing and ultimately improve the oral feeding of pre-term infants with SSwB coordination disorders in a relatively short period of time.