Conformational Control in Diterpene Synthase TlnA: Elucidating the Mechanism of 5-8-6 Skeleton Formation through Ring Expansion.

TlnA produces a distinct cyclohexane-fused 5-8-6 ring system, different from the prevalent 5-8-5 scaffold synthesized by well-established enzymes. This study identifies two conformations of a carbocation intermediate, revealing how the enzyme environment prohibits one conformation due to steric hindrance, thereby directing the formation of the 5-8-6 system over the 5-8-5 scaffold. This investigation enhances our understanding of diterpene biosynthesis and the impact of enzyme environments on chemical reactions, providing valuable insights into the formation of complex cyclic structures.

Analysis of the correlations between the extracranial internal carotid artery and extracranial vertebral artery and mild cognitive impairment.

BACKGROUND: Vascular tortuosity is a prevalent morphological change that frequently occurs in arteries across different parts of the body. OBJECTIVE: To analyze the relationship between the tortuosities of the extracranial internal carotid artery (EICA) and extracranial vertebral artery (EVA) with mild cognitive impairment. METHODS: The tortuosity index (TI), vascular deviation degree, tortuosity degree, and angle number of the EICA and EVA were retrospectively analyzed and calculated in 160 patients who underwent computed tomography angiography (CTA) in this study's department, and the Montreal cognitive assessment was adopted to evaluate the cognitive function of the patients. RESULTS: The differences in age, gender, arterial hypertension (AH), and diabetes mellitus (DM) between the normal group and the mild cognitive impairment group were statistically significant (p< 0.01). The TI was negatively correlated with the score of cognitive function. The tortuosities of the EICA and EVA were correlated with mild cognitive impairment (p< 0.05). The reduction in visual-spatial ability was correlated with the right EICA tortuosity, and the reduction in memory was correlated with the EVA tortuosity. Age, gender, HP, DM, and coronary heart disease (CHD) were potential risk factors for carotid tortuosity (p< 0.05). CONCLUSION: There was a significant correlation observed between the TIs of both the EICA and EVA and the presence of mild cognitive impairment. Advanced age, female, HP, DM, and CHD were independent risk factors for EICA and EVA tortuosities.

Changes in the intestinal microbiota of patients with Parkinson's disease and their clinical significance.

OBJECTIVE: To investigate the differences and their clinical significance in the intestinal microbiota in patients with Parkinson's disease (PD) in comparison to those in healthy controls. MATERIALS AND METHODS: 20 patients with PD who received treatment in the First Affiliated Hospital of Bengbu Medical College between January 2019 and December 2019 were selected as the research subjects to form the PD group, while 20 age- and gender-matched healthy volunteers were selected as the control group. Fecal samples from the two groups were collected, and the V4 region of 16S-ribosomal ribonucleic acid was selected for high-throughput sequencing analysis to explore any differences, as well as their significance, in the intestinal microbiota abundance at the class, family, and genus levels between the two study groups. RESULTS: The operational taxonomic unit cluster analysis revealed a high degree of overlap between the patients with PD and the controls. Compared with the controls, the relative abundance of Coriobacteriia and Coriobacteriaceae was increased in the PD group (p < 0.01), while the relative abundance of Lachnospiraceae was significantly lower (p < 0.01). The relative abundance of Collinsella, Escherichia, and Fusobacterium in the PD group was significantly higher than in the control group (p < 0.05). CONCLUSION: Compared with the healthy subjects, the abundance of specific microflora was significantly different in the PD patients at the class, family, and genus level. Intestinal flora may act as a potential biomarker for PD and provide a theoretical basis for microflora transplantation therapy.

Study on the pro-inflammatory mechanism of the HuD antibody in promoting M1 polarization and paraneoplastic neurological syndrome occurrence.

Paraneoplastic neurological syndrome (PNS) is a nonmetastatic complication of malignant tumors that may lead to immune-mediated neuronal dysfunction or death. The occurrence of PNS results from the binding of anti-neuronal antibodies to neuronal cell surface antigens or intracellular antigens, which hinders the function of target proteins and promotes cell death. The aim of this study is to research the effect and immune mechanism of the neuronal ELAV-like protein (HuD antibody) on PNS-related syndrome. Neuronal cells were co-cultured with monocyte macrophages with or without HuD antibody. Next, we detected the apoptosis of neuronal cells by flow cytometry. Meantime, macrophage M1/M2 polarization factors and the secretion of inflammatory factors in the co-culture system were also detected by quantitative polymerase chain reaction (qPCR), Western blots and ELISA technologies. The results showed that after adding the HuD antibody in the co-culture system, the apoptosis level of the neuroma cells were significantly increased, and the apoptosis level were not significant changed when co-culture with monocytes without HuD antibody. In addition, the level of factors of M1 macrophages TNF-α, IL-12, TGF-ß and IFN-γ increased, while the level of factors of M2 macrophages IL-10, IL-4, and Arg-1 decreased. The outcomes demonstrated that absorption of the HuD antibody by cerebellar neuronal cells could promote the proliferation of M1 macrophages and stimulates macrophages to secrete inflammatory factors, further damage the neuronal cells, eventually resulting in the occurrence of PNS. This finding provided a theoretical basis for the subsequent treatment and prevention of PNS.

The clinical data from 19 critically ill patients with coronavirus disease 2019: a single-centered, retrospective, observational study.

Background: The objectives of this study were to analyze the clinical features of coronavirus disease 2019 (COVID-19) and evaluate the diagnosis and treatment. Methods: A retrospective analysis of the clinical manifestation and auxiliary examination of 19 patients with COVID-19 from the Liyuan Hospital intensive care unit (ICU) between January 16, 2020 and February 20, 2020 was undertaken. Results: There were 11 male and 8 female cases among the patients. The median (range) age was 73 (38-91) years. Of these patients, 8 (42.1%) had died and the median duration from ICU admission to death was 2 (interquartile range (IQR): 1-10.75) days. Seven of these 8 patients had underlying diseases. The auxiliary examination showed fever (68.4%), dry cough (15.8%), dyspnea (10.5%), and diarrhea (5.3%). All 19 cases showed ground-glass changes on chest computed tomography. Serum hypersensitive C-reactive protein (hs-CRP) and serum amylase A (SAA) were clearly increased in all of the cases. Among the 19 cases, there were 16 (84.2%) cases in which the total number of lymphocytes decreased, 12 cases (63%) had reduced liver function, and 11 cases (58%) had deviant results for fibrinogen (FIB) and D-dimer, in particular, the D-dimer level was significantly higher in the non-survivors compared with the survivors. Conclusion: There were more men than women among critically ill patients. All of the cases showed ground-glass changes on chest computed tomography and the vast majority of patients displayed fever and dry cough. The clinical laboratory indices change significantly, especially the D-dimer level among non-survivors.

ChaiQi Decoction Alleviates Vascular Endothelial Injury by Downregulating the Inflammatory Response in ApoE-Model Mice.

Metabolic syndrome (MetS) is a pathological state of metabolic disorders that primarily occur in human proteins, fats, and carbohydrates. It is a complex cluster of core metabolic disorder syndromes including obesity, hyperglycemia, dyslipidemia, and hypertension, and vascular endothelial injury, occurring over time. The currently available treatment options cannot effectively manage MetS. In our previous research, we revealed ChaiQi decoction (CQD) as an effective prescription for improving MetS; however, the specific mechanism remains unclear. Herein, we assessed the efficacy and mechanism of CQD in ApoE gene knockout (ApoE-) mice. Mice were administered with CQD daily for 12 weeks, and the measurement of their body weight was taken monthly. To evaluate the metabolic levels of mice, we determined the fasting blood glucose (FBG), fasting serum insulin (FINS), insulin resistance index (IRI), triglyceride (TG), total cholesterol (TC), high-density lipoprotein cholesterol (HDL-C), and low-density lipoprotein cholesterol (LDL-C) levels. Furthermore, immunohistochemical analysis was adopted to determine the expression of ICAM-1 and VCAM-1 in vascular endothelium, while an optical microscope was adopted to observe the pathological morphology of abdominal aorta in mice. Tumor necrosis factor-α (TNF-α), interleukin-6 (IL-6), intercellular cell adhesion molecule-1 (ICAM-1), and vascular cell adhesion molecule-1 (VCAM-1) levels were determined using the ELISA method, whereas Western blotting was used to determine nuclear factor- (NF-) κB p65. Of note, intragastric CQD administration ameliorated ApoE-model mice, as evidenced by reduced levels of FBG, FINS, IRI, TG, TC, and LDL-C. Furthermore, CQD alleviated vascular endothelial injury and regularized the structure of the abdominal aorta by downregulating the expressions of proinflammatory cytokines TNF-α, IL-6, ICAM-1, VCAM-1, and NF-κB p65. Overall, these findings advocated that CQD ameliorates metabolic levels and vascular endothelial injury in mice by downregulating the inflammatory response and thus may be utilized as a novel MetS therapy.