Publications by authors named "Geng Li"

365 Publications

Multilevel Resistive Random Access Memory Achieved by MoO3/Hf/MoO3 Stack and its Application in Tunable High-Pass Filter.

Nanotechnology 2021 Jun 11. Epub 2021 Jun 11.

Xi'an Jiaotong University, No.8 Xian Ning West Road, Xi'an City, Xi'an, 710049, CHINA.

In this work, the multilevel resistive random access memories (RRAMs) have been achieved by using the structure of Pt/MoO3/Hf/MoO3/Pt with four stable resistance states. The devices show good retention property of each state (>104s) and large memory window (>104). The simulation and experimental study reveal that the resistive switching mechanism is ascribed to combination of the conductive filament in the stack of MoO3/Hf next to the top electrode and redox reaction at the interface of Hf/MoO3 next to bottom electrode. The fitting results of current-voltage (I-V) characteristics under low sweep voltage indicate that the conduction of HRSs is dominated by the Poole-Frenkel (P-F) emission and that of LRS is governed by the Ohmic conduction. Based on the RRAM, the tunable high-pass filter (HPF) with configurable filtering characteristics has been realized. The gain-frequency characteristics of the programmable HPF show that the filter has high resolution and wide programming range, demonstrating the viability of the multilevel RRAMs for future spiking neural network and shrinking the programmable filters with low power consumption.
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http://dx.doi.org/10.1088/1361-6528/ac0ac4DOI Listing
June 2021

UPLC-MS-Based Serum Metabolomics Reveals Potential Biomarkers of Ang II-Induced Hypertension in Mice.

Front Cardiovasc Med 2021 5;8:683859. Epub 2021 May 5.

Laboratory of Cardiovascular Research, School of Medicine, Jiangnan University, Wuxi, China.

Hypertension is caused by polygenic inheritance and the interaction of various environmental factors. Abnormal function of the renin-angiotensin-aldosterone system (RAAS) is closely associated with changes in blood pressure. As an essential factor in the RAAS, angiotensin II (Ang II) contributes to vasoconstriction and inflammatory responses. However, the effects of overproduction of Ang II on the whole body-metabolism have been unclear. In this study, we established a hypertensive mouse model by micro-osmotic pump perfusion of Ang II, and the maximum systolic blood pressure reached 140 mmHg after 2 weeks. By ultra-performance liquid chromatography-quadrupole time-of-flight mass spectrometry, the metabolites in the serum of hypertensive model and control mice were analyzed. Partial least squares discriminant analysis (PLS-DA) in both positive and negative ionization modes showed clear separation of the two groups. Perfusion of Ang II induced perturbations of multiple metabolic pathways in mice, such as steroid hormone biosynthesis and galactose metabolism. Tandem mass spectrometry revealed 40 metabolite markers with potential diagnostic value for hypertension. Our data indicate that non-targeted metabolomics can reveal biochemical pathways associated with Ang II-induced hypertension. Although researches about the clinical use of these metabolites as potential biomarkers in hypertension is still needed, the current study improves the understanding of systemic metabolic response to sustained release of Ang II in hypertensive mice, providing a new panel of biomarkers that may be used to predict blood pressure fluctuations in the early stages of hypertension.
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http://dx.doi.org/10.3389/fcvm.2021.683859DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8131677PMC
May 2021

Intravenous contrast does not improve detection of nerve lesions or active muscle denervation changes in MR neurography of the common peroneal nerve.

Skeletal Radiol 2021 May 22. Epub 2021 May 22.

Department of Radiology, University of Wisconsin School of Medicine and Public Health, 600 E. Highland Avenue, Madison, WI, 53792, USA.

Objective: To evaluate the effect of intravenous (IV) contrast on sensitivity, specificity, and accuracy of magnetic resonance (MR) neurography of the knee with attention to the common peroneal nerve (CPN) in identifying nerve lesions and active muscle denervation changes.

Materials And Methods: A retrospective search for contrast-enhanced MR neurography cases evaluating the CPN at the knee was performed. Patients with electrodiagnostic testing (EDX) within 3 months of imaging were included and those with relevant prior surgery were excluded. Two radiologists independently reviewed non-contrast sequences and then 4 weeks later evaluated non-contrast and contrast sequences. McNemar's tests were performed to detect a difference between non-contrast only and combined non-contrast and contrast sequences in identifying nerve lesions and active muscle denervation changes using EDX as the reference standard.

Results: Forty-four exams in 42 patients (2 bilateral) were included. Twenty-eight cases had common peroneal neuropathy and 29, 21, and 9 cases had active denervation changes in the anterior, lateral, and posterior compartment/proximal muscles respectively on EDX. Sensitivity, specificity, and accuracy of non-contrast versus combined non-contrast and contrast sequences for common peroneal neuropathy were 50.0%, 56.2%, and 52.3% versus 50.0%, 56.2%, and 52.3% for reader 1 and 57.1%, 50.0%, and 54.5% versus 64.3%, 56.2%, and 61.4% for reader 2. Sensitivity, specificity, and accuracy of non-contrast and combined non-contrast and contrast sequences in identifying active denervation changes for anterior, lateral, and posterior compartment muscles were not significantly different. McNemar's tests were all negative.

Conclusion: IV contrast does not improve the ability of MR neurography to detect CPN lesions or active muscle denervation changes.
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http://dx.doi.org/10.1007/s00256-021-03812-wDOI Listing
May 2021

Edible Bird's Nest Ameliorates Dextran Sulfate Sodium-Induced Ulcerative Colitis in C57BL/6J Mice by Restoring the Th17/Treg Cell Balance.

Front Pharmacol 2021 21;12:632602. Epub 2021 Apr 21.

Guangdong Key Laboratory for Research and Development of Natural Drugs, Key Laboratory of Research and Development of New Medical Materials of Guangdong Medical University, School of Pharmacy, Guangdong Medical University, Dongguan, China.

Ulcerative colitis (UC) is a type of inflammatory bowel disease (IBD) with a complex aetiology that commonly recurs. Most drugs for UC treatment interfere with metabolism and immune responses, often causing some serious adverse reactions. Therefore, the development of alternative treatments, including nutritional supplements and probiotics, have been one of the main areas of current research due to fewer side effect. As both a Chinese medicine and a food, edible bird's nest (EBN) has high nutritional value. Modern pharmacological studies have shown that it has anti-inflammatory, immunoregulatory, antiviral and neuroprotective effects. In this study, UC was induced with dextran sulfate sodium (DSS) to investigate the protective effect of EBN on colitis mice and the related mechanism. The body weight, faecal morphology and faecal occult blood results of mice were recorded every day from the beginning of the modelling period. After the end of the experiment, the length of the colon was measured, and the colon was collected for histopathological detection, inflammatory factor detection and immunohistochemical detection. Mouse spleens were dissected for flow cytometry. The results showed that in mice with colitis, EBN improved symptoms of colitis, reduced colonic injury, and inhibited the increases in the levels of the pro-inflammatory cytokines IL-1β and TNF-α. The T helper 17 (Th17)/regulatory T (Treg) cell balance was restored by decreasing the expression of IL-17A and IL-6 in intestinal tissues, increasing the expression of TGF-β, and decreasing the number of Th17 cells in each EBN dose group. These findings suggest that EBN has a protective effect on DSS-mediated colitis in mice, mainly by restoring the Th17/Treg cell balance.
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http://dx.doi.org/10.3389/fphar.2021.632602DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8097138PMC
April 2021

Antiviral Activity of Isoimperatorin Against Influenza A Virus and its Inhibition of Neuraminidase.

Front Pharmacol 2021 13;12:657826. Epub 2021 Apr 13.

Laboratory Animal Center, Guangzhou University of Chinese Medicine, Guangzhou, China.

Influenza A virus (IAV) poses a severe threat to human health and is a major public health problem worldwide. As global anti-influenza virus drug resistance has increased significantly, there is an urgent need to develop new antiviral drugs, especially drugs from natural products. Isoimperatorin, an active natural furanocoumarin, exhibits a broad range of pharmacologic activities including anticoagulant, analgesic, anti-inflammatory, antibacterial, anti-tumor, and other pharmacological effects, so it has attracted more and more attention. In this study, the antiviral and mechanistic effects of isoimperatorin on influenza A virus were studied. Isoimperatorin illustrated a broad-spectrum antiviral effect, especially against the A/FM/1/47 (H1N1), A/WSN/33 (H1N1, S31N, amantadine resistant), A/Puerto Rico/8/34 (H1N1), and A/Chicken/Guangdong/1996 (H9N2) virus strains. The experimental results of different administration modes showed that isoimperatorin had the best antiviral activity under the treatment mode. Further time-of-addition experiment results indicated that when isoimperatorin was added at the later stage of the virus replication cycle (6-8 h, 8-10 h), it exhibited an effective antiviral effect, and the virus yield was reduced by 81.4 and 84.6%, respectively. In addition, isoimperatorin had no effect on the expression of the three viral RNAs (mRNA, vRNA, and cRNA). Both the neuraminidase (NA) inhibition assay and CETSA demonstrated that isoimperatorin exerts an inhibitory effect on NA-mediated progeny virus release. The molecular docking experiment simulated the direct interaction between isoimperatorin and NA protein amino acid residues. In summary, isoimperatorin can be used as a potential agent for the prevention and treatment of influenza A virus.
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http://dx.doi.org/10.3389/fphar.2021.657826DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8077232PMC
April 2021

miR-335-5p aggravates type 2 diabetes by inhibiting SLC2A4 expression.

Biochem Biophys Res Commun 2021 Jun 23;558:71-78. Epub 2021 Apr 23.

Department of Endocrinology, Hubei Third People's Hospital Affiliated to Jianghan University, Wuhan, 430300, Hubei, China. Electronic address:

Globally, type 2 diabetes (T2D) is the most common chronic disease. It affects approximately 500 million people worldwide. Dysregulation of the solute carrier family 2 member 4 (SLC2A4) gene and miR-335-5p has been associated with T2D progression. However, the mechanisms underlying this dysregulation are unclear. The levels of miR-335-5p and SLC2A4 in blood samples collected from patients with T2D (T2D blood samples) and pancreatic cell lines were measured by Real Time quantitative PCR (RT-qPCR). The relationship between miR-335-5p and SLC2A4 was investigated using a luciferase assay. The role of the miR-335-5p-SLC2A4 axis was detected by CCK8, BrdU, and caspase-3 assays in pancreatic cells treated with 25 mM glucose. Increased miR-335-5p and decreased SLC2A4 expression was observed in both T2D blood samples and pancreatic cell lines. The miR-335-5p mimic markedly suppressed proliferation and elevated apoptosis in glucose-treated pancreatic cells. SLC2A4 overexpression significantly enhanced proliferation but inhibited apoptosis in glucose-treated pancreatic cells. Moreover, miR-335-5p inhibited the expression of SLC2A4 in the pancreatic cells and suppressed the growth of these cells. The data indicated that miR-335-5p targeting of SLC2A4 could hamper the growth of T2D cell model by inhibiting their proliferation and elevating apoptosis. Collectively, our findings implicate miR-335-5p and SLC2A4 as potentially effective therapeutic targets for patients with T2D.
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http://dx.doi.org/10.1016/j.bbrc.2021.04.011DOI Listing
June 2021

Equilibrium free-energy differences from a linear nonequilibrium equality.

Authors:
Geng Li Z C Tu

Phys Rev E 2021 Mar;103(3-1):032146

Department of Physics, Beijing Normal University, Beijing 100875, China.

Extracting equilibrium information from nonequilibrium measurements is a challenge task of great importance in understanding the thermodynamic properties of physical, chemical, and biological systems. The discovery of the Jarzynski equality illumines the way to estimate the equilibrium free-energy difference from the work performed in nonequilibrium driving processes. However, the nonlinear (exponential) relation causes the poor convergence of the Jarzynski equality. Here, we propose a concise method to estimate the free-energy difference through a linear nonequilibrium equality which inherently converges faster than nonlinear nonequilibrium equalities. This linear nonequilibrium equality relies on an accelerated isothermal process which is realized by using a unified variational approach, named variational shortcuts to isothermality. We apply our method to an underdamped Brownian particle moving in a double-well potential. The simulations confirm that the method can be used to accurately estimate the free-energy difference with high efficiency. Especially during fast driving processes with high dissipation, the method can improve the accuracy by more than an order of magnitude compared with the estimator based on the nonlinear nonequilibrium equality.
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http://dx.doi.org/10.1103/PhysRevE.103.032146DOI Listing
March 2021

[Construction of model for multidimensional evaluation of value and risk of Chinese patent medicine].

Zhongguo Zhong Yao Za Zhi 2021 Mar;46(5):1284-1292

Institute of Chinese Materia Medica,China Academy of Chinese Medical Sciences Beijing 100070,China.

It is the core of the development for Chinese patent medicine enterprises to cultivate large varieties of Chinese patent medicine, and the selection of potential "seed" products is the prerequisite for the cultivation strategy. By constructing the evaluation model from multiple dimensions of value and risk, we can conduct specialized evaluation of Chinese patent medicines to effectively, professionally and objectively select the "seed" products with large variety cultivation potential. In this paper, the establishment of a multidimensional evaluation system would be discussed from the aspects of drug naming and prescription composition, safety risk and supply guarantee of raw materials and medicinal materials, competition situation, access to policy catalogue, scientific and technological support, clinical evidence and recognition, systematical and standardized collection of information on product instructions, quality standards, policy catalogue, scientific and technological literature, market competition and clinical application of Chinese patent medicines. Through the objective evaluation index and the range of objective index, the multi-dimensional evaluation model on values and risks of Chinese patent medicine products was discussed. Based on this model, a batch of Chinese patent medicine products can be quickly and comprehensively analyzed, and quantitative comparison can be formed among different types and fields of products. According to the evaluation results of the model and the comprehensive evaluation of experts, high-quality "seed" products can be selec-ted, laying a solid foundation for the next step of large variety cultivation. With use of this model, we can further clarify the external competitive advantages and internal priority levels of each product, and provide support for enterprises to optimize product structure and improve product strategic layout.
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http://dx.doi.org/10.19540/j.cnki.cjcmm.20201214.601DOI Listing
March 2021

Genetic Identification of Edible Bird's Nest in Thailand Based on ARMS-PCR.

Front Genet 2021 8;12:632232. Epub 2021 Mar 8.

Guangdong Yunfu Vocational College of Chinese Medicine, Yunfu, China.

Edible bird's nest (EBN) is a popular delicacy in the Asian Pacific region originating from Indonesia, Malaysia, Thailand and Vietnam, which consist of various potential medicine value in Traditional Chinese Medicine (TCM). Thailand is one of the main exporters of EBN. However, the genetic information of EBN, a key part of molecular biology, has yet to be reported in Thailand. It is necessary to explore the genetic information of EBN in Thailand based on a quick and simple method to help protect the rights and interests of consumers. This research aimed to systematically evaluate different methods of extracting EBN DNA to improve the efficiency of the analysis of cytochrome b (Cytb) and NADH dehydrogenase subunit 2 (ND2) gene sequences, the establishment of phylogenetic trees, and the genetic information of EBN in Thailand. Additionally, we aimed to develop a quick and simple method for identifying EBN from different species based on the genetic information and amplification-refractory mutation system PCR (ARMS-PCR). By comparing the four methods [cetyltrimethylammonium bromide (CTAB), sodium dodecyl sulfate (SDS), kit and guanidinium isothiocyanate methods] for EBN extraction, we found that the guanidinium isothiocyanate method was the optimal extraction method. Phylogenetic trees generated on the basis of Cytb and ND2 gene analyses showed that 26 samples of house EBN and 4 samples of cave EBN came from and , respectively. In addition, to distinguish different samples from different species of , we designed 4 polymerase chain reaction (PCR) amplification primers based on the ND2 gene sequences of and . The ARMS-PCR results showed band lengths for EBN of 533, 402, and 201 bp, while those for EBN were 463, 317, and 201 bp. Collectively, the results showed that ARMS-PCR is a fast and simple method for the genetic identification of EBN based on designing specific original identification primers.
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http://dx.doi.org/10.3389/fgene.2021.632232DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7983251PMC
March 2021

Global analysis of lysine 2-hydroxyisobutyrylation in wheat root.

Sci Rep 2021 Mar 18;11(1):6327. Epub 2021 Mar 18.

Crop Research Institute, Shandong Academy of Agricultural Sciences, Ji'nan, Shandong, 250100, People's Republic of China.

Lysine 2-hydroxyisobutyrylation (Khib) is a novel naturally occurring post-translational modification. The system Khib identification at proteomics level has been performed in various species and tissues to characterize the role of Khib in biological activities. However, the study of Khib in plant species is relatively less. In the present study, the first plant root tissues lysine 2-hydroxyisobutyrylome analysis was performed in wheat with antibody immunoprecipitation affinity, high resolution mass spectrometry-based proteomics and bioinformatics analysis. In total, 6328 Khib sites in 2186 proteins were repeatedly identified in three replicates. These Khib proteins showed a wide subcellular location distribution. Function and pathways characterization of these Khib proteins indicated that many cellular functions and metabolism pathways were potentially affected by this modification. Protein and amino acid metabolism related process may be regulated by Khib, especially ribosome activities and proteins biosynthesis process. Carbohydrate metabolism and energy production related processes including glycolysis/gluconeogenesis, TCA cycle and oxidative phosphorylation pathways were also affected by Khib modification. Besides, root sulfur assimilation and transformation related enzymes exhibited Khib modification. Our work illustrated the potential regulation role of Khib in wheat root physiology and biology, which could be used as a useful reference for Khib study in plant root.
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http://dx.doi.org/10.1038/s41598-021-85879-yDOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7973580PMC
March 2021

Clinical outcomes following surgical mitral valve repair or replacement in patients with rheumatic heart disease: a meta-analysis.

Ann Transl Med 2021 Feb;9(3):204

Department of Cardiovascular Surgery, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China.

Background: The clinical outcome of mitral valve repair (MVP) is considerably more favorable than that of mitral valve replacement (MVR) in patients with degenerative mitral disease. However, rheumatic heart disease (RHD) is still the predominant cause of mitral valve surgery in developing countries and the advantages of MVP in RHD have still not been definitely proven. The aim of this meta-analysis was thus to evaluate the suitability of MVP in patients with RHD. Considering the difference between mechanical and biological valves, we distinguished them from each other and compared them with MVP individually.

Methods: A comparison of clinical outcomes of MVP and MVR in patients with RHD was performed based on clinical trial data. Relevant articles published from January 1, 1990 until March 1, 2020 were identified in Pubmed, Cochrane Library, and China National Knowledge Infrastructure database (CNKI). Studies that lacked direct comparisons between MVP and MVR were excluded.

Results: A total of 16 studies with 8659 patients were included in the analysis. The MVP group displayed lower early and long-term mortality, and fewer valve-related events and major adverse events. However, this patient group required more reoperations compared with the MVR group. Similar results were observed after distinguishing between mechanical and bioprosthetic valves to compare MVP with MVR (mech-valves), but no statistically significant difference was identified in the reoperation rate between MVP and MVR (bio-valves). MVP was further associated with increased risk of mitral reoperation in patients undergoing concomitant aortic valve replacement (AVR) surgery but without any improved early and long-term survival.

Conclusions: MVP and MVR are beneficial for patients with RHD. For skilled surgeons, MVP can be performed for some suitable patients with RHD and is preferred for elderly patients or patients with contraindications of anticoagulation. However, MVR is more appropriate when concomitant AVR is needed.
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http://dx.doi.org/10.21037/atm-20-3542DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7940942PMC
February 2021

Observation of magnetic adatom-induced Majorana vortex and its hybridization with field-induced Majorana vortex in an iron-based superconductor.

Nat Commun 2021 Mar 1;12(1):1348. Epub 2021 Mar 1.

Beijing National Laboratory for Condensed Matter Physics and Institute of Physics, Chinese Academy of Sciences, Beijing, China.

Braiding Majorana zero modes is essential for fault-tolerant topological quantum computing. Iron-based superconductors with nontrivial band topology have recently emerged as a surprisingly promising platform for creating distinct Majorana zero modes in magnetic vortices in a single material and at relatively high temperatures. The magnetic field-induced Abrikosov vortex lattice makes it difficult to braid a set of Majorana zero modes or to study the coupling of a Majorana doublet due to overlapping wave functions. Here we report the observation of the proposed quantum anomalous vortex with integer quantized vortex core states and the Majorana zero mode induced by magnetic Fe adatoms deposited on the surface. We observe its hybridization with a nearby field-induced Majorana vortex in iron-based superconductor FeTeSe. We also observe vortex-free Yu-Shiba-Rusinov bound states at the Fe adatoms with a weaker coupling to the substrate, and discover a reversible transition between Yu-Shiba-Rusinov states and Majorana zero mode by manipulating the exchange coupling strength. The dual origin of the Majorana zero modes, from magnetic adatoms and external magnetic field, provides a new single-material platform for studying their interactions and braiding in superconductors bearing topological band structures.
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http://dx.doi.org/10.1038/s41467-021-21646-xDOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7921435PMC
March 2021

Physcion, a novel inhibitor of 5α-reductase that promotes hair growth in vitro and in vivo.

Arch Dermatol Res 2021 Feb 26. Epub 2021 Feb 26.

Laboratory Animal Center, Guangzhou University of Chinese Medicine, Guangzhou, 510405, China.

Androgenic alopecia (AGA) has a high incidence. Excess dihydrotestosterone in blood capillaries, which is converted from testosterone by 5α-reductase, is an AGA causative factor. We identified the inhibitory activity of four Polygonum multiflorum compounds against 5α-reductase via high-performance liquid chromatography, and the results showed that Physcion was a potent 5α-reductase inhibitor. Additionally, we found that through inhibiting 5α-reductase expression, Physcion could shorten the time of dorsal skin darkening and hair growth, improve hair follicle morphology, and significantly increase hair follicle count. Eventually, through molecular docking study, we found the binding energy and molecular interactions between Physcion and 5α-reductase type II. These results suggested that Physcion is a potent 5α-reductase inhibitor, as well as a new natural medicine for treating AGA.
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http://dx.doi.org/10.1007/s00403-021-02195-1DOI Listing
February 2021

The mass spectrometric fragmentation mechanisms of catenulane and isocatenulane diterpenes.

Org Biomol Chem 2021 03;19(10):2224-2232

Kekulé-Institute of Organic Chemistry and Biochemistry, University of Bonn, Gerhard-Domagk-Strasse 1, 53121 Bonn, Germany.

Two new diterpene derivatives were obtained by semisynthesis from enzymatically generated catenul-14-en-6-ol. The EI-MS fragmentation mechanisms of three enzyme products and the two semisynthetic derivatives were investigated by extensive 13C-labelling experiments.
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http://dx.doi.org/10.1039/d1ob00160dDOI Listing
March 2021

Surgical repair of mitral valve bileaflet prolapse in pediatric patients.

J Card Surg 2021 Jun 18;36(6):1858-1863. Epub 2021 Feb 18.

Department of Cardiovascular Surgery, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China.

Background: Pediatric mitral regurgitation (MR), especially with bileaflet prolapse, is relatively rare, of high complexity, and frequently associated with other congenital cardiac abnormalities. It remains a major therapeutic challenge for surgeons. This study reports our experience of surgical treatment of this mitral disease and midterm follow-up results.

Methods: Between January 2016 and April 2020, nine pediatric patients, six females and three males, age ranged from 3 to 12 years (median age was 6 years) with a weight range of 12-36 kg (median weight was 25 kg), who all had over moderate regurgitation caused by bileaflet prolapse with mean distance of leaflet coaptation beyond annular plane 5.89 ± 1.66 mm (4-9 mm), received mitral valve (MV) repair. Various surgical techniques were used to repair MV.

Results: The median follow-up period was 23(6-51) months, only one patient had moderately severe recurrent of MR, no patient developed systolic anterior motion (SAM) or mitral stenosis. Freedom from reoperation was 100% during the follow-up period. Compared to preoperation, the left atrial (LA) diameter and left ventricular end-diastolic diameter (LVEDD) decreased significantly from 2.94 ± 0.49 cm to 2.37 ± 0.38 cm (LA, p < .01) and from 4.13 ± 0.73 cm to 3.62 ± 0.49 cm (LVEDD, p < .01) respectively, ejection fraction (EF) decreased significantly (p < .05) from 68.56 ± 3.98% to 62.89 ± 4.48% before discharged.

Conclusion: We share our experience of surgical repair of mitral valve bileaflet prolapse in pediatric patients. Several surgical methods are considered to be used to repair the MV due to the high complexity of lesions. Anatomic correction or functional correction in our reports almost reaches the same result, while functional correction means simpler operation.
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http://dx.doi.org/10.1111/jocs.15432DOI Listing
June 2021

Chinese herbal formula Xuefu Zhuyu for primary dysmenorrhea patients (CheruPDYS): a study protocol for a randomized placebo-controlled trial.

Trials 2021 Jan 26;22(1):95. Epub 2021 Jan 26.

The Second Affiliated Hospital of Guangzhou University of Chinese Medicine, Guangzhou, Guangdong, China.

Background: Epidemiological studies have shown that young women often suffer from primary dysmenorrhea (PD) which is a common cause that affects their routine work and quality of life. Chinese herbal medicine has been widely used for PD in China. A systematic review found that Xuefu Zhuyu (XFZY) has a promising effect on PD management, yet there is a dearth of high-quality evidence in support of this claim. We want to conduct a randomized controlled trial to evaluate the efficacy and safety of XFZY for PD patients.

Methods: This is a protocol for a multicenter, randomized, placebo-controlled trial. A total of 248 participants with PD will be recruited at 6 centers and randomized into two groups-a herbal treatment group and a placebo group. The participants will receive either XFZY or placebo, three times per day, for 3 menstrual cycles, with a 12-week follow-up. The primary outcome will be the mean change in pain intensity as measured by VAS, while the change in menstrual pain duration, the change in peak pain intensity as measured by VAS, the Cox Menstrual Symptom Scale (CMSS), quality of life EQ-5D-5L, cumulative painkiller consumption, and health economics will be included as secondary outcomes. Adverse events will also be reported.

Discussion: This protocol describes a multicenter, double-blind, randomized, placebo-controlled trial that investigates the efficacy and safety of XFZY for primary dysmenorrhea. Validated evaluation tools will assess dysmenorrhea severity. We believe that this research will provide important evidence regarding the use of XFZY to treat dysmenorrhea.

Trial Registration: Chinese Clinical Trial Registry ChiCTR1900026819 . Registered on 23 October 2019.
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http://dx.doi.org/10.1186/s13063-021-05050-wDOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7835651PMC
January 2021

"Quick" MRIs without contrast in the setting of pediatric abscess drainage: A comparative analysis of clinical outcomes.

J Pediatr Surg 2021 Jan 14. Epub 2021 Jan 14.

University of Wisconsin Madison, Department of Radiology, 600 Highland Drive, Madison, WI 53792, USA. Electronic address:

Background/purpose: To assess the use of "quick" MRI without contrast in the setting of percutaneous drain management in pediatric patients.

Methods: A retrospective medical record review was conducted to compare "quick" MRI without contrast to CT in the pediatric percutaneous drain placement setting. The study included 111 patients under 18-years-old having undergone percutaneous drain placement between January 2014 and January 2019. The "quick" MRI protocol consists of axial single-shot-fast-spin-echo (SSFSE) and fat-saturated SSFSE coronal sequences. Primary clinical outcomes included number of additional drain placement procedures, complications, length of hospitalization, and repeat drainage within 6 months following drain-free interval. The use of "quick" MRI post-procedurally was also investigated.

Results: Patients with pre-drain "quick" MRIs instead of CTs had no significant difference in the need for additional drain placement (p = 1), length of hospitalization (p = 0.275), or drainage complications (p = 0.728). Patients receiving "quick" MRI for follow-up imaging post-drain placement had no greater rate of repeat drainage within 6 months of initial drain discontinuation (p = 0.90) when compared to patients having CT.

Conclusions: Pre and post-drainage procedure "quick" MRIs were found to be equivalent to CT in regard to several key clinical outcomes.
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http://dx.doi.org/10.1016/j.jpedsurg.2021.01.010DOI Listing
January 2021

How Well Do Commonly Used Co-contraction Indices Approximate Lower Limb Joint Stiffness Trends During Gait for Individuals Post-stroke?

Front Bioeng Biotechnol 2020 7;8:588908. Epub 2021 Jan 7.

Rice Computational Neuromechanics Laboratory, Department of Mechanical Engineering, Rice University, Houston, TX, United States.

Muscle co-contraction generates joint stiffness to improve stability and accuracy during limb movement but at the expense of higher energetic cost. However, quantification of joint stiffness is difficult using either experimental or computational means. In contrast, quantification of muscle co-contraction using an EMG-based Co-Contraction Index (CCI) is easier and may offer an alternative for estimating joint stiffness. This study investigated the feasibility of using two common CCIs to approximate lower limb joint stiffness trends during gait. Calibrated EMG-driven lower extremity musculoskeletal models constructed for two individuals post-stroke were used to generate the quantities required for CCI calculations and model-based estimation of joint stiffness. CCIs were calculated for various combinations of antagonist muscle pairs based on two common CCI formulations: Rudolph et al. (2000) () and Falconer and Winter (1985) (). measures antagonist muscle activation relative to not only total activation of agonist plus antagonist muscles but also agonist muscle activation, while measures antagonist muscle activation relative to only total muscle activation. We computed the correlation between these two CCIs and model-based estimates of sagittal plane joint stiffness for the hip, knee, and ankle of both legs. Although we observed moderate to strong correlations between some CCI formulations and corresponding joint stiffness, these associations were highly dependent on the methodological choices made for CCI computation. Specifically, we found that: (1) was generally more correlated with joint stiffness than was , (2) CCI calculation using EMG signals with calibrated electromechanical delay generally yielded the best correlations with joint stiffness, and (3) choice of antagonist muscle pairs significantly influenced CCI correlation with joint stiffness. By providing guidance on how methodological choices influence CCI correlation with joint stiffness trends, this study may facilitate a simpler alternate approach for studying joint stiffness during human movement.
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http://dx.doi.org/10.3389/fbioe.2020.588908DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7817819PMC
January 2021

Cellular and molecular landscape of mammalian sinoatrial node revealed by single-cell RNA sequencing.

Nat Commun 2021 01 12;12(1):287. Epub 2021 Jan 12.

Department of Cardiology, Shanghai East Hospital, Tongji University School of Medicine, Shanghai, 200120, China.

Bioelectrical impulses intrinsically generated within the sinoatrial node (SAN) trigger the contraction of the heart in mammals. Though discovered over a century ago, the molecular and cellular features of the SAN that underpin its critical function in the heart are uncharted territory. Here, we identify four distinct transcriptional clusters by single-cell RNA sequencing in the mouse SAN. Functional analysis of differentially expressed genes identifies a core cell cluster enriched in the electrogenic genes. The similar cellular features are also observed in the SAN from both rabbit and cynomolgus monkey. Notably, Vsnl1, a core cell cluster marker in mouse, is abundantly expressed in SAN, but is barely detectable in atrium or ventricle, suggesting that Vsnl1 is a potential SAN marker. Importantly, deficiency of Vsnl1 not only reduces the beating rate of human induced pluripotent stem cell - derived cardiomyocytes (hiPSC-CMs) but also the heart rate of mice. Furthermore, weighted gene co-expression network analysis (WGCNA) unveiled the core gene regulation network governing the function of the SAN in mice. Overall, these findings reveal the whole transcriptome profiling of the SAN at single-cell resolution, representing an advance toward understanding of both the biology and the pathology of SAN.
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http://dx.doi.org/10.1038/s41467-020-20448-xDOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7804277PMC
January 2021

Shielded goethite catalyst that enables fast water dissociation in bipolar membranes.

Nat Commun 2021 Jan 4;12(1). Epub 2021 Jan 4.

CAS Key Laboratory of Soft Matter Chemistry, Collaborative Innovation Centre of Chemistry for Energy Materials, Department of Applied Chemistry, School of Chemistry and Materials Science, University of Science and Technology of China, 230026, Hefei, China.

Optimal pH conditions for efficient artificial photosynthesis, hydrogen/oxygen evolution reactions, and photoreduction of carbon dioxide are now successfully achievable with catalytic bipolar membranes-integrated water dissociation and in-situ acid-base generations. However, inefficiency and instability are severe issues in state-of-the-art membranes, which need to urgently resolve with systematic membrane designs and innovative, inexpensive junctional catalysts. Here we show a shielding and in-situ formation strategy of fully-interconnected earth-abundant goethite FeO(OH) catalyst, which lowers the activation energy barrier from 5.15 to 1.06 eV per HO - H bond and fabricates energy-efficient, cost-effective, and durable shielded catalytic bipolar membranes. Small water dissociation voltages at limiting current density (U: 0.8 V) and 100 mA cm (U: 1.1 V), outstanding cyclic stability at 637 mA cm, long-time electro-stability, and fast acid-base generations (HSO: 3.9 ± 0.19 and NaOH: 4.4 ± 0.21 M m min at 100 mA cm) infer confident potential use of the novel bipolar membranes in emerging sustainable technologies.
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http://dx.doi.org/10.1038/s41467-020-20131-1DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7782813PMC
January 2021

Effect of Weekly Antibiotic Round on Antibiotic Use in the Neonatal Intensive Care Unit as Antibiotic Stewardship Strategy.

Front Pediatr 2020 15;8:604244. Epub 2020 Dec 15.

Neonatal Center, Beijing Children's Hospital, Capital Medical University, Beijing, China.

Antibiotics are commonly used in the neonatal intensive care unit (NICU). The objective was to observe the effect of weekly antibiotic round in NICU (WARN) to the antibiotic use in NICU. A retrospective observational study was performed. Departmental-level diagnosis categories and the parameters of antibiotic usage in NICU for the period of 2016-2017 (Phase 1) and 2018-2019 (Phase 2) were collected. WARN in NICU was started since January 2018. A time series forecasting was used to predict the quarterly antibiotic use in Phase 2, based on data from Phase 1. The actual antibiotic use of each quarter in Phase 2 was compared with the predicted values. Totally 9297 neonates were included (4743 in Phase 1, 4488 in Phase 2). The composition of the disease spectrum between Phase 1 and Phase 2 was not different ( > 0.05). In Phase 1 and Phase 2, the overall antibiotic rate was 94.4 and 74.2%, the average accumulative defined daily dose per month was 199.00 ± 55.77 and 66.80 ± 45.64, the median antibiotic use density per month was 10.31 (9.00-13.27) and 2.48 (1.92-4.66), the median accumulative defined daily dose per case per month was 0.10 (0.09-0.13) and 0.03 (0.02-0.47), the number of patients who received any kind of antibiotic per 1000 hospital days per month was 103.45 (99.30-107.48) and 78.66 (74.62-82.77), rate of culture investigation before antibiotics was 64 to 92%, respectively, and all were better than the predicted values ( < 0.01). The implementation of periodical antibiotic rounds was effective in reducing the antibiotics use in the NICU.
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http://dx.doi.org/10.3389/fped.2020.604244DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7769868PMC
December 2020

Polysaccharides Attenuate Ovalbumin-Induced Allergic Rhinitis in Rats by Inhibiting NLRP3 Inflammasome Activation and NOD2-Mediated NF-B Activation.

J Med Food 2021 Jan 23;24(1):1-9. Epub 2020 Dec 23.

Department of Pharmacy, The First Affiliated Hospital of Guangzhou University of Chinese Medicine, Guangzhou, China.

Allergic rhinitis (AR) is an IgE-mediated chronic inflammatory disease of the allergic nasal mucosa. It has a significant effect on quality life; most patients with AR also suffer from sleep disorders, mood disorders, and deterioration in social relationships. As increasing numbers of medicinal plants show productive anti-inflammatory activity against inflammatory diseases, there is growing interest in natural medicinal plant ingredients. To this end, we selected polysaccharides (APS) to evaluate its anti-inflammatory effect on ovalbumin-induced AR rats, and we further explored its impact on NLRP3 inflammasome activation and NOD2-mediated NF-B activation. We found that APS can alleviate the nasal symptom of AR rats and attenuate pathological alterations. APS also reduced the inflammatory cytokine levels. APS not only inhibited the NLRP3 inflammasome activation but also inhibited NF-B activation by decreasing NOD2 expression and blocking the phosphorylation of NF-B (p65). In conclusion, APS can effectively improve the inflammatory symptoms of nasal mucosa in AR rats, which may be mediated by the inhibition of NLRP3 inflammasome activation and NOD2-mediated NF-B activation. These findings indicate that APS has the potential to be used as a therapeutic agent for AR.
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http://dx.doi.org/10.1089/jmf.2020.4750DOI Listing
January 2021

Ganghuo Kanggan Decoction in Influenza: Integrating Network Pharmacology and Pharmacological Evaluation.

Front Pharmacol 2020 10;11:607027. Epub 2020 Dec 10.

The First Affiliated Hospital of Guangzhou University of Chinese Medicine, Guangzhou, China.

Ganghuo Kanggan decoction (GHKGD) is a clinical experience prescription used for the treatment of viral pneumonia in the Lingnan area of China, and its clinical effect is remarkable. However, the mechanism of GHKGD in influenza is still unclear. To predict the active components and signaling pathway of GHKGD and to explore its therapeutic mechanism in influenza and to verified it using network pharmacology. The potential active components and therapeutic targets of GHKGD in the treatment of influenza were hypothesized through a series of network pharmacological strategies, including compound screening, target prediction and pathway enrichment analysis. Based on the target network and enrichment results, a mouse model of influenza A virus (IAV) infection was established to evaluate the therapeutic effect of GHKGD on influenza and to verify the possible molecular mechanism predicted by network pharmacology. A total of 116 candidate active compounds and 17 potential targets were identified. The results of the potential target enrichment analysis suggested GHKGD may involve the RLR signaling pathway to reduce inflammation in the lungs. experiments showed that GHKGD had a protective effect on pneumonia caused by IAV-infected mice. Compared with the untreated group, the weight loss in the GHKGD group in the BALB/c mice decreased, and the inflammatory pathological changes in lung tissue were reduced ( < 0.05). The expression of NP protein and the virus titers in lung were significantly decreased ( < 0.05). The protein expression of RIG-I, NF-kB, and STAT1 and the level of MAVS and IRF3/7 mRNA were remarkably inhibited in GHKGD group ( < 0.05). After the treatment with GHKGD, the level of Th1 cytokines (IFN-γ, TNF-α, IL-2) was increased, while the expression of Th2 (IL-5, IL4) cytokines was reduced ( < 0.05). Through a network pharmacology strategy and experiments, the multi-target and multi-component pharmacological characteristics of GHKGD in the treatment of influenza were revealed, and regulation of the RLR signaling pathway during the anti-influenza process was confirmed. This study provides a theoretical basis for the research and development of new drugs from GHKGD.
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http://dx.doi.org/10.3389/fphar.2020.607027DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7759152PMC
December 2020

Profiling circulating T follicular helper cells and their effects on B cells in post-cardiac transplant recipients.

Ann Transl Med 2020 Nov;8(21):1369

Department of Cardiovascular Surgery, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China.

Background: To evaluate circulating T follicular helper (cTfh) cells and characterize their function in chronic-phase recipients after heart transplantation.

Methods: Participants were divided into healthy control (HC, n=40), preoperative (Pre, n=40), and post-transplantation chronic-phase recipient (1-year, n=40) groups. The percentages of cTfh cell subsets and CD19 B cell subsets were measured using flow cytometry. co-culture experiments were performed using cTfh cells and B cells isolated by fluorescence-activated cell sorting. Plasma concentrations of IL-21, chemokine ligand 13 (CXCL13), immunoglobulin G1 (IgG1), and immunoglobulin G3 (IgG3) were quantified using enzyme-linked immunosorbent assays (ELISA).

Results: cTfh and programmed cell death protein 1-positive (PD-1) cTfh cells, the cTfh17/cTfh ratio, and class-switched memory B cells in peripheral blood were significantly increased in the 1-year group versus the HC and Pre groups (P<0.01), whereas the cTfh1/cTfh ratio and number of naïve B cells were significantly decreased in the 1-year group. Co-culture experiments showed that cTfh cells promoted B cell differentiation to plasmablasts. In the 1-year group, cTfh and PD-1 cTfh cell numbers were positively correlated with plasmablasts in CD19 B cells (P<0.01). The cTfh17/cTfh ratio was positively correlated with IgG3 concentrations in plasma (P<0.01). The plasma concentrations of interleukin-21 (IL-21) and CXCL13 in the 1-year group were increased compared to the HC and Pre groups (P<0.05). Chronic-phase recipients had increased proportions of CD4CXCR5 and CD4CXCR5PD-1 cTfh cells, with a cTfh1-to-cTfh17 subtype conversion. An increased number of cTfh cells was positively correlated with B cell differentiation to plasmablasts, class-switched memory B cells, and greater IgG production.

Conclusions: During the chronic phase, the proportion of cTfh cells increased and enhanced B cell responses. The cTfh-related soluble factors CXCL13 and IL-21 may regulate the immunopathogenesis of chronic immune injury. Thus, cTfh cells may drive long-term immune rejection in chronic-phase recipients after heart transplantation.
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http://dx.doi.org/10.21037/atm-20-3027DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7723658PMC
November 2020

The haplotypes of various TNF related genes associated with scleritis in Chinese Han.

Hum Genomics 2020 12 7;14(1):46. Epub 2020 Dec 7.

Department of Ophthalmology, The First Affiliated Hospital of Zhengzhou University, Henan Province Eye Hospital, Henan International Joint Research Laboratory for Ocular Immunology and Retinal Injury Repair, Jianshe East Road 1, Zhengzhou, 450052, People's Republic of China.

Background: Several studies have stated that TNF-α participates in the pathogenesis of scleritis, but also in several systemic autoimmune diseases and vasculitis, of which some are associated with scleritis. Earlier GWAS and SNP studies have confirmed that multiple SNPs of TNF related genes are associated with many immune-mediated disorders. The purpose of this study was to examine the association of TNF related gene polymorphisms with scleritis in Chinese Han. A case-control study was carried out in 556 non-infectious scleritis cases and 742 normal controls. A total of 28 single-nucleotide polymorphisms (SNPs) were genotyped by the iPLEXGold genotyping assay.

Results: No significant correlations were seen between the individual SNPs in the TNF related genes and scleritis. Haplotype analysis showed a significantly decreased frequency of a TNFAIP3 TGT haplotype (order of SNPs: rs9494885, rs3799491, rs2230926) (Pc = 0.021, OR = 0.717, 95% CI = 0.563-0.913) and a significantly increased frequency of a TNFSF4 GT haplotype (order of SNPs: rs3850641, rs704840) (Pc = 0.004, OR = 1.691, 95% CI = 1.205-2.372) and TNFSF15 CCC haplotype (order of SNPs: rs6478106, rs3810936, rs7865494) (Pc = 0.012, OR = 1.662, 95% CI = 1.168-2.363) in patients with scleritis as compared with healthy volunteers.

Conclusions: This study reveals that a TGT haplotype in TNFAIP3 may be a protective factor for the development of scleritis and that a GT haplotype in TNFSF4 and a CCC haplotype in TNFSF15 may be risk factors for scleritis in Chinese Han.
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http://dx.doi.org/10.1186/s40246-020-00296-yDOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7720609PMC
December 2020

circFN1 Mediates Sorafenib Resistance of Hepatocellular Carcinoma Cells by Sponging miR-1205 and Regulating E2F1 Expression.

Mol Ther Nucleic Acids 2020 Dec 2;22:421-433. Epub 2020 Sep 2.

Department of Hepato-Pancreato-Biliary Surgery, The Affiliated Suzhou Hospital of Nanjing Medical University, Suzhou 215001, China.

In recent years, circular RNAs (circRNAs) have been shown to have critical regulatory roles in the resistance to anti-cancer drugs. However, the contributions of circRNAs to sorafenib resistance in hepatocellular carcinoma (HCC) remain largely unknown. The present study aims to explore the involvement of circFN1 in sorafenib resistance and how circFN1 is associated with the miR-1205/E2F1 pathway, which have been demonstrated to mediate this resistance in HCC cells. We investigated the expression of circRNAs in five paired sorafenib-sensitive HepG2 cells and sorafenib-resistant (SR)-HepG2 cells by microarray analysis. The quantitative real-time PCR analysis was used to investigate the expression pattern of circFN1 in HCC patient tissues and cell lines. Then, the effects of circFN1 on sorafenib resistance, cell proliferation, and apoptosis were assessed in HCC and . In this study, circFN1 was observed to be upregulated in HCC patient tissues and cell lines. Overexpression of circFN1 in HCC was significantly correlated with aggressive characteristics and served as an independent risk factor for overall survival in patients with HCC. Our and data indicated that inhibition of circFN1 enhances the sorafenib sensitivity of HCC cells. Mechanistically, we found that circFN1 could promote the expression of E2F1 by sponging miR-1205. In summary, our study demonstrated that circFN1 contributes to sorafenib resistance by regulating the miR-1205/E2F1 signaling pathway. These results indicate that circFN1 may represent a potentially valuable target for overcoming sorafenib resistance for HCC.
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http://dx.doi.org/10.1016/j.omtn.2020.08.039DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7533358PMC
December 2020

A new Majorana platform in an Fe-As bilayer superconductor.

Nat Commun 2020 Nov 10;11(1):5688. Epub 2020 Nov 10.

Beijing National Laboratory for Condensed Matter Physics and Institute of Physics, Chinese Academy of Sciences, 100190, Beijing, China.

Iron-chalcogenide superconductors have emerged as a promising Majorana platform for topological quantum computation. By combining topological band and superconductivity in a single material, they provide significant advantage to realize isolated Majorana zero modes. However, iron-chalcogenide superconductors, especially Fe(Te,Se), suffer from strong inhomogeneity which may hamper their practical application. In addition, some iron-pnictide superconductors have been demonstrated to have topological surface states, yet no Majorana zero mode has been observed inside their vortices, raising a question of universality about this new Majorana platform. In this work, through angle-resolved photoemission spectroscopy and scanning tunneling microscopy/spectroscopy measurement, we identify Dirac surface states and Majorana zero modes, respectively, for the first time in an iron-pnictide superconductor, CaKFeAs. More strikingly, the multiple vortex bound states with integer-quantization sequences can be accurately reproduced by our model calculation, firmly establishing Majorana nature of the zero mode.
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http://dx.doi.org/10.1038/s41467-020-19487-1DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7655862PMC
November 2020

Diterpene Biosynthesis in Catenulispora acidiphila: On the Mechanism of Catenul-14-en-6-ol Synthase.

Angew Chem Int Ed Engl 2021 01 10;60(3):1488-1492. Epub 2020 Dec 10.

Kekulé-Institute of Organic Chemistry and Biochemistry, University of Bonn, Gerhard-Domagk-Strasse 1, 53121, Bonn, Germany.

A new diterpene synthase from the actinomycete Catenulispora acidiphila was identified and the structures of its products were elucidated, including the absolute configurations by an enantioselective deuteration approach. The mechanism of the cationic terpene cyclisation cascade was deeply studied through the use of isotopically labelled substrates and of substrate analogues with partially blocked reactivity, resulting in derailment products that gave further insights into the intermediates along the cascade. Their chemistry was studied, leading to the biomimetic synthesis of a diterpenoid analogue of a brominated sesquiterpene known from the red seaweed Laurencia microcladia.
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http://dx.doi.org/10.1002/anie.202014180DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7839432PMC
January 2021