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1.
Environ Sci Technol ; 58(26): 11675-11684, 2024 Jul 02.
Article de Anglais | MEDLINE | ID: mdl-38952298

RÉSUMÉ

Excessive anthropogenic phosphorus (P) emissions put constant pressure on aquatic ecosystems. This pressure can be quantified as the freshwater eutrophication potential (FEP) by linking P emissions, P fate in environmental compartments, and the potentially disappeared fraction of species due to increase of P concentrations in freshwater. However, previous fate modeling on global and regional scales is mainly based on the eight-direction algorithm without distinguishing pollution sources. The algorithm fails to characterize the fate paths of point-source emissions via subsurface pipelines and wastewater treatment infrastructure, and exhibits suboptimal performance in accounting for multidirectional paths caused by river bifurcations, especially in flat terrains. Here we aim to improve the fate modeling by incorporating various fate paths and addressing multidirectional scenarios. We also update the P estimates by complementing potential untreated point-source emissions (PSu). The improved method is examined in a rapidly urbanizing area in Taihu Lake Basin, China in 2017 at a spatial resolution of 100 m × 100 m. Results show that the contribution of PSu on FEP (62.6%) is greater than that on P emissions (58.5%). The FEP is more spatially widely distributed with the improved fate modeling, facilitating targeted regulatory strategies tailored to local conditions.


Sujet(s)
Eutrophisation , Eau douce , Phosphore , Eau douce/composition chimique , Modèles théoriques , Surveillance de l'environnement , Chine , Polluants chimiques de l'eau/analyse , Écosystème
2.
PhytoKeys ; 243: 1-8, 2024.
Article de Anglais | MEDLINE | ID: mdl-38912086

RÉSUMÉ

Petrocodonliboensis Sheng H.Tang & Jia W.Yang is a new species of Gesneriaceae from Guizhou, southwestern China. The new taxon has a pale-yellow corolla and is most similar to P.luteoflorus. However, it differs from the latter by having a urceolate (vs. cannulate) corolla tube, an abaxial corolla lip 0.8-1.1 mm (vs. 2-2.2 mm) long, and filaments 1.5-1.7 mm (vs. ca. 7 mm) long that are straight (vs. S-shaped or geniculate near the middle). The new taxon is assessed as "Data Deficient" (DD) according to the IUCN standards.

3.
Org Lett ; 26(18): 3810-3815, 2024 May 10.
Article de Anglais | MEDLINE | ID: mdl-38678579

RÉSUMÉ

A visible-light-driven photocatalytic protocol is established for the diastereoselective synthesis of pyrrolo[3,2,1-jk]carbazoles via a radical-triggered multicomponent bicyclization reaction starting from readily available indole-tethered 1,6-enynes and α-benzyl-α-bromomalonates under mild conditions. This photocatalytic approach exhibits a wide substrate compatibility and excellent tolerability toward various functional groups and boasts the benefit of efficient ring formation and chemical bond creation.

4.
Org Lett ; 26(18): 3828-3833, 2024 May 10.
Article de Anglais | MEDLINE | ID: mdl-38684050

RÉSUMÉ

The photocatalyzed radical-triggered thio/selenosulfonylation-bicyclization of indole-tethered 1,6-enynes has been established for the first time, enabling the synthesis of various previously unreported thio/selenosulfonylated benzo[c]pyrrolo[1,2,3-lm]carbazoles with moderate to good yields under mild conditions. The reaction pathway was proposed, consisting of energy transfer, homolytic cleavage, radical addition, 5-exo-dig, radical coupling, and a Mallory reaction cascade. This approach exhibits a wide substrate compatibility and excellent tolerability toward various functional groups and is characterized by its remarkable efficiency in both bond formation and annulation.

5.
Clin Transl Oncol ; 2024 Apr 20.
Article de Anglais | MEDLINE | ID: mdl-38642258

RÉSUMÉ

BACKGROUND: Transmembrane protein 92 (TMEM92) has been implicated in the facilitation of tumor progression. Nevertheless, comprehensive analyses concerning the prognostic significance of TMEM92, as well as its role in immunological responses across diverse cancer types, remain to be elucidated. METHODS: In this study, data was sourced from a range of publicly accessible online platforms and databases, including TCGA, GTEx, UCSC Xena, CCLE, cBioPortal, HPA, TIMER2.0, GEPIA, CancerSEA, GDSC, exoRBase, and ImmuCellAI. We systematically analyzed the expression patterns of TMEM92 at both mRNA and protein levels across diverse human organs, tissues, extracellular vesicles (EVs), and cell lines associated with multiple cancer types. Subsequently, analyses were conducted to determine the relationship between TMEM92 and various parameters such as prognosis, DNA methylation, copy number variation (CNV), the tumor microenvironment (TME), immune cell infiltration, genes with immunological relevance, tumor mutational burden (TMB), microsatellite instability (MSI), mismatch repair (MMR), and half-maximal inhibitory concentration (IC50) values. RESULTS: In the present study, we observed a pronounced overexpression of TMEM92 across a majority of cancer types, which was concomitantly associated with a less favorable prognosis. A notable association emerged between TMEM92 expression and both DNA methylation and CNV. Furthermore, a pronounced relationship was discerned between TMEM92 expression, the TME, and the degree of immune cell infiltration. Intriguingly, while TMEM92 expression displayed a positive correlation with macrophage presence, it inversely correlated with the infiltration level of CD8 + T cells. Concurrently, significant associations were identified between TMEM92 and the major histocompatibility complex, TMB, MSI, and MMR. Results derived from Gene Set Enrichment Analysis and Gene Set Variation Analysis further substantiated the nexus of TMEM92 with both immune and metabolic pathways within the oncogenic context. CONCLUSIONS: These findings expanded the understanding of the roles of TMEM92 in tumorigenesis and progression and suggest that TMEM92 may have an immunoregulatory role in several malignancies.

6.
Exp Ther Med ; 27(3): 115, 2024 Mar.
Article de Anglais | MEDLINE | ID: mdl-38361518

RÉSUMÉ

Mitochondrial dysfunction plays a critical role in the development and exacerbation of heart failure (HF). Dynamin-related protein 1 (Drp1), a key regulator of mitochondrial fission, influences cardiac energy metabolism. The present study investigated the relationship between serum Drp1 levels and the prognosis of patients with HF across a broad spectrum. Serum Drp1 concentrations were measured using ELISA. The primary outcome was the risk of composite major adverse cardiac events (MACEs), which included instances of cardiac death and HF-related readmissions. To assess the prognostic significance of serum Drp1, a receiver operating characteristic curve was constructed to predict MACE-free survival. Additionally, an optimal threshold value for Drp1 was determined and was used to stratify patients into different risk categories. A total of 256 HF patients were finally included and categorized into two groups based on their serum Drp1 levels, labeled as the low (Drp1 ≤2.66 ng/ml, n=101) and high group (Drp1 >2.66 ng/ml, n=155). Patients with low serum Drp1 concentrations showed impaired heart structure and function, as assessed by echocardiography. The 6-month follow-up results indicated that patients with reduced Drp1 concentrations faced a substantially increased risk of MACEs (21.1% vs. 2.8%; P<0.001). The present study revealed that diminished serum Drp1 concentrations could potentially act as a predictive marker for the prognosis of HF in a broad patient population.

7.
Nucleic Acids Res ; 52(D1): D72-D80, 2024 Jan 05.
Article de Anglais | MEDLINE | ID: mdl-37904589

RÉSUMÉ

G-quadruplexes (G4s) are non-canonical four-stranded structures and are emerging as novel genetic regulatory elements. However, a comprehensive genomic annotation of endogenous G4s (eG4s) and systematic characterization of their regulatory network are still lacking, posing major challenges for eG4 research. Here, we present EndoQuad (https://EndoQuad.chenzxlab.cn/) to address these pressing issues by integrating high-throughput experimental data. First, based on high-quality genome-wide eG4s mapping datasets (human: 1181; mouse: 24; chicken: 2) generated by G4 ChIP-seq/CUT&Tag, we generate a reference set of genome-wide eG4s. Our multi-omics analyses show that most eG4s are identified in one or a few cell types. The eG4s with higher occurrences across samples are more structurally stable, evolutionarily conserved, enriched in promoter regions, mark highly expressed genes and associate with complex regulatory programs, demonstrating higher confidence level for further experiments. Finally, we integrate millions of functional genomic variants and prioritize eG4s with regulatory functions in disease and cancer contexts. These efforts have culminated in the comprehensive and interactive database of experimentally validated DNA eG4s. As such, EndoQuad enables users to easily access, download and repurpose these data for their own research. EndoQuad will become a one-stop resource for eG4 research and lay the foundation for future functional studies.


Sujet(s)
Bases de données génétiques , G-quadruplexes , Séquences d'acides nucléiques régulatrices , Animaux , Humains , Souris , Génome , Génomique
8.
Article de Chinois | WPRIM (Pacifique Occidental) | ID: wpr-1030918

RÉSUMÉ

According to the global cancer statistics in 2022 updated by the International Agency for Research on Cancer (IARC), there were nearly 20 million new cases of cancer and 9.7 million deaths. Lung cancer was the most commonly diagnosed cancer, accounting for nearly 2.5 million new cases (12.4% of all global cancers), followed by female breast cancer (11.6%), colorectal cancer (9.6%), prostate cancer (7.3%), and stomach cancer (4.9%). Lung cancer was also the leading cause of cancer deaths, with an estimated 1.8 million deaths (18.7%), followed by colorectal cancer (9.3%), liver cancer (7.8%), female breast cancer (6.9%), and stomach cancer (6.8%). Population-based projections suggest that the number of new cancer cases will reach 35 million by 2050. Increasing the investment in prevention and control measures targeting key cancer risk factors, including smoking, obesity, and infections, could save many lives globally and bring significant economic and social returns to countries in the coming decades.

9.
Article de Chinois | WPRIM (Pacifique Occidental) | ID: wpr-1024051

RÉSUMÉ

Objective Corruption is the most common cadaver phenomenon in forensic practice and an important basis for inferring time of death(PMI),but the definition of corruption degree and the construction of model inference models have always been difficult in the practice of forensic science.Methods In this study,the late postmortem phenomena were observed.Meanwhile,the microbial flora structure of gut and gravesoil and the nature of gravesoil were detected,for analyzing the changes before and after the key moment of abdominal rupture which naturally happened during the cadaver decay.Results The results found that from the macroscopic and microscopic levels,there were significant differences in cadaver decay,including microbial flora structure and gravesoil properties before and after the key moment of the natural abdominal rupture during cadaver decay.The phenomena are highly observable and can be accurately judged by forensic examinations,as well as related means in the field of biology and physiochemistry.In this study,this critical event was called Rupture Point.Conclusion The Rupture Point can be used as an important node for the assessment of cadaver decay degree in the practice of forensic medicine.It can be utilized for a cut-off point as well when constructing PMI inference models based on microbial flora structure changes.The accuracy of PMI inference models can be improved when the models were constructed in segments.

10.
Article de Chinois | WPRIM (Pacifique Occidental) | ID: wpr-1039100

RÉSUMÉ

ObjectiveBody fluid stains left at crime scenes are frequently trace amounts, while the identification of body fluids through real time fluorogenic quantitative technique often necessitates the repeated detection within the limited sample, as multiple miRNA markers are the basis for the identification. Based on the goal of both the throughput and efficiency improvement of miRNA analysis in trace samples, a duplex real time fluorogenic quantitative PCR assay system was designed to accurately quantify two miRNAs simultaneously, and the system should be further verified by actual sample for the body fluid identification. MethodsThe duplex real time fluorogenic quantitative PCR system of miR-451a to miR-21-5p was established with specially designed primers and probes, and the concentrations of the primers and probes were both optimized. The specificity, sensitivity and reproducibility of the system were validated, while its capability for body fluid identification was assessed using the miR-451a to miR-21-5p ratio. ResultsThe optimized assay system exhibited excellent specificity and repeatability, with coefficients of variation consistently below 8% for both intra- and inter-batch variability. The amplification efficiency of miR-451a and miR-21-5p reached 71.77% and 74.81%, respectively, with high and relatively consistent results. By utilizing this duplex real time fluorogenic quantitative PCR assay system, a total of 58 body fluid samples were analyzed, exhibiting a discrimination rate of 100% between blood and non-blood samples, as well as between peripheral blood and menstrual blood samples. Moreover, the results, obtained from single real time fluorogenic quantitative PCR assay system and duplex real time fluorogenic quantitative PCR assay system, showed no statistically significant difference with randomly selected blood samples (n=20). Compared to previous single real time fluorogenic quantitative PCR assay system, the sensitivity of duplex real time fluorogenic quantitative PCR assay system exhibited remarkable improvement. A minimum input of only 0.1 ng total RNA was sufficient for accurate detection of peripheral blood and menstrual blood samples, while saliva, semen, and vaginal secretion required only 1 ng total RNA for precise identification purposes. Additionally, the duplex real time fluorogenic quantitative PCR assay system successfully differentiated between different types of body fluids in simulated samples under natural outdoor conditions. ConclusionThe duplex real time fluorogenic quantitative PCR assay system effectively reduced both the time and material costs by half compared to the single system, especially suitable for the examination of body fluid stains left at crime scenes, solving the contradiction between the trace amount and the multiple sample volumes demand of repeated real time fluorogenic quantitative PCR. The duplex real time fluorogenic quantitative PCR assay successfully distinguished blood and other body fluid, as well as peripheral blood and menstrual blood samples, which maintains an equivalent capability for body fluid identification with half sample, time and reagent consumption. This system provides an efficient tool for identifying suspicious body fluids, as well as a foundation for more multiplexed real time fluorogenic quantitative PCR assay system research.

11.
Article de Chinois | WPRIM (Pacifique Occidental) | ID: wpr-1039140

RÉSUMÉ

Since the beginning of the 21st century, the field of cancer drug development has undergone significant changes. Kinase inhibitors are the product category with the highest number of approved drugs and indications. However, despite checkpoint inhibitors being only introduced to the market since 2011, they have become the second most approved product categories. In the year of 2023, the FDA’s Center for Drug Evaluation and Research (CDER) has approved 13 new cancer therapeutic drugs. In the past five years, a slight increase in drug approvals targeting biomarker-defined populations as well as emerging approvals that are agnostic to tumor anatomy has been recorded. Currently, new treatment approaches and technologies, such as the development of Artificial Intelligence (AI), have increasingly profound progress on cancer drug development.

12.
Article de Chinois | WPRIM (Pacifique Occidental) | ID: wpr-1003404

RÉSUMÉ

ObjectiveTo explore the mechanism and pathway of Gandou Fumu decoction (GDFMD) in the development of liver fibrosis in Wilson's disease (WD). MethodFirst, 30 TX-j mice were randomly divided into the model group, high-dose, medium-dose, and low-dose GDFMD groups, and penicillamine group, with six mice in each group, and another six wild-type mice were used as the normal group. The high-dose, medium-dose, and low-dose GDFMD groups were intragastrically administered drugs of 13.92, 6.96, 3.48 g·kg-1. In the penicillamine group, 0.1 g·kg-1 of penicillamine was given by intragastric administration. The model group and the normal group were given equal volume of normal saline, once a day, for four consecutive weeks. Samples were collected four weeks after gavage, and enzyme-linked immunosorbent assay (ELISA) was used to detect type Ⅲ procollagen peptide (PCⅢ), collagen type Ⅳ (Col Ⅳ), hyaluronic acid (HA), and laminin (LN). Hematoxylin-eosin (HE), Masson, and picric acid-Sirus red collagen (Sirus Red) staining were used to observe the histopathological changes of liver fibrosis. Real-time fluorescence quantitative polymerase chain reaction (Real-time PCR), immunohistochemistry, and Western blot were used to observe the expressions of α-smooth muscle actin (α-SMA) and collagen type Ⅰ (Col Ⅰ), which were related to the activation of hepatic stellate cells (HSCs). The expression of miR-29b-3p was observed by Real-time PCR. The expression of Unc-51-like kinase 1 (ULK1) and its downstream-related factors were observed by Western blot. The downstream genes of miR-29b-3p were verified by the dual luciferase reporter gene detection method. ResultCompared with the normal group, the four items of liver fibrosis (PCⅢ, Col Ⅳ, HA, and LN) in the model group were significantly abnormal (P<0.01), and the pathology was significantly abnormal. The expression of HSC activation-related indicators including α-SMA and Col Ⅰ, as well as α-SMA mRNA and Col Ⅰ mRNA was up-regulated (P<0.05, P<0.01), and miR-29b-3p expression was down-regulated (P<0.01). ULK1, p-ULK1, autophagy-related gene 13 (Atg13), p-Atg13, Beclin-1, FAK family kinase-interacting protein of 200 kDa (FIP200), activating molecule in BECN1-regulated autophagy protein 1 (AMBKA1), and microtubule-associated protein 1 light chain 3Ⅱ/Ⅰ(LC3Ⅱ/Ⅰ) were up-regulated (P<0.05, P<0.01). p62 protein expression was down-regulated (P<0.01). Compared with the model group, the four items of liver fibrosis in the high-dose, medium-dose, and low-dose GDFMD groups and the penicillamine group were significantly improve (P<0.01), and the pathological conditions were improved. The expression of HSC activation-related indicators including α-SMA and Col Ⅰ, as well as α-SMA mRNA and Col Ⅰ mRNA was down-regulated (P<0.05, P<0.01), and the expression of miR-29b-3p was up-regulated (P<0.01). ULK1, p-ULK1, Atg13, p-Atg13, Beclin-1, FIP200, AMBKA1, and LC3Ⅱ/Ⅰ were down-regulated (P<0.05, P<0.01), and p62 protein expression was up-regulated (P<0.01). The prediction software predicted that there was a binding site between miR-29b-3p and ULK1. The dual-luciferase reporter gene detection method indicated that the luciferase activity of the ULK1-WT plasmid-transfected cell group was reduced when miR-29b-3p mimics were co-cultured (P<0.01). ConclusionGDFMD can regulate ULK1-mediated autophagy by up-regulating miR-29b-3p and further exert its anti-hepatic fibrosis effect in Wilson's disease.

13.
Cell Biosci ; 13(1): 117, 2023 Jun 28.
Article de Anglais | MEDLINE | ID: mdl-37381029

RÉSUMÉ

G-quadruplex (G4) is a four-stranded helical DNA secondary structure formed by guanine-rich sequence folding, and G4 has been computationally predicted to exist in a wide range of species. Substantial evidence has supported the formation of endogenous G4 (eG4) in living cells and revealed its regulatory dynamics and critical roles in several important biological processes, making eG4 a regulator of gene expression perturbation and a promising therapeutic target in disease biology. Here, we reviewed the methods for prediction of potential G4 sequences (PQS) and detection of eG4s. We also highlighted the factors affecting the dynamics of eG4s and the effects of eG4 dynamics. Finally, we discussed the future applications of eG4 dynamics in disease therapy.

14.
Zhongguo Zhong Yao Za Zhi ; 48(12): 3132-3139, 2023 Jun.
Article de Chinois | MEDLINE | ID: mdl-37381995

RÉSUMÉ

Strigolactones(SLs) are a class of sesquiterpenoids derived from the carotenoid biosynthesis pathway with the core carbon skeleton consisting of tricyclic lactone(ABC tricyclic ring) and α,ß-unsaturated furan ring(D ring). SLs are widely distributed in higher plants and are symbiotic signals between plants and Arbuscular mycorrhiza(AM), which play key roles in the evolution of plant colonizing terrestrial habitats. As a new type of plant hormone, SLs possess such important biological functions as inhibiting shoot branching(tillers), regulating root architecture, promoting secondary growth, and improving plant stress resistance. Therefore, SLs have attracted wide attention. The biological functions of SLs are not only closely related to the formation of "excellent shape and quality" of Chinese medicinal materials but also have important practical significance for the production of high-quality medicinal materials. However, SLs have been currently widely studied in model plants and crops such as Oryza sativa and Arabidopsis thaliana, and few related studies have been reported on SLs in medicinal plants, which need to be strengthened. This review focused on the latest research progress in the isolation and identification, biological and artificial synthesis pathways, biosynthesis sites and transport modes, signal transduction pathways and mechanisms, and biological functions of SLs, and prospected the research on the regulation mechanism of SLs in the growth and development of medicinal plants and their related application on targeted regulation of Chinese herbal medicine production, which is expected to provide some references for the in-depth research on SLs in the field of Chinese medicinal resources.


Sujet(s)
Arabidopsis , Plantes médicinales , Lactones
15.
J Orthop Surg Res ; 18(1): 282, 2023 Apr 07.
Article de Anglais | MEDLINE | ID: mdl-37024933

RÉSUMÉ

BACKGROUND: To explore the surgical technique and clinical outcomes of cementless total hip arthroplasty (THA) combined with impacted bone grafting for the treatment of moderate and severe acetabular protrusion with rheumatoid arthritis (RA). METHODS: From January 2010 to October 2020, 45 patients (56 hips), including 17 men (22 hips) and 28 women (34 hips) with acetabular impingement secondary to RA, were treated with bioprosthetic THA combined with autologous bone grafting at our hospital. According to the Sotello-Garza and Charnley classification criteria, there were 40 cases (49 hips) of type II (protrusio acetabuli 6-15 mm) and 5 cases (7 hips) of type III (protrusio acetabuli > 15 mm). At the postoperative follow-up, the ROM of the hip joint, the VAS score, and the Harris score were evaluated. The healing of the bone graft, the restoration of the hip rotation center, and the prosthesis loosening were assessed by plain anteroposterior radiographs. RESULTS: The average operation time was 95.53 ± 22.45 min, and the mean blood loss was 156.16 ± 69.25 mL. There were no neurovascular complications during the operation. The mean follow-up duration was 5.20 ± 1.20 years. The horizontal distance of the hip rotation center increased from preoperative 10.40 ± 2.50 mm to postoperative 24.03 ± 1.77 mm, and the vertical distance increased from preoperative 72.36 ± 3.10 mm to postoperative 92.48 ± 5.31 mm. The range of flexion motion of the hip joint increased from 39.48 ± 8.36° preoperatively to 103.07 ± 7.64° postoperatively, and the range of abduction motion increased from 10.86 ± 4.34° preoperatively to 36.75 ± 3.99° postoperatively. At the last follow-up, the Harris score increased from 37.84 ± 4.74 to 89.55 ± 4.05. All patients were able to move independently without assistance. CONCLUSIONS: Cementless THA combined with impacted grafting granule bone of the autogenous femoral head and biological acetabular cup can reconstruct the acetabulum, restore the rotation center of the hip joint, and achieve good medium-term outcomes in the treatment of moderate to severe acetabular herniation secondary to RA.


Sujet(s)
Polyarthrite rhumatoïde , Arthroplastie prothétique de hanche , Prothèse de hanche , Mâle , Humains , Femelle , Arthroplastie prothétique de hanche/effets indésirables , Arthroplastie prothétique de hanche/méthodes , Acétabulum/imagerie diagnostique , Acétabulum/chirurgie , Articulation de la hanche/imagerie diagnostique , Articulation de la hanche/chirurgie , Polyarthrite rhumatoïde/complications , Polyarthrite rhumatoïde/imagerie diagnostique , Polyarthrite rhumatoïde/chirurgie , Résultat thérapeutique , Études de suivi , Études rétrospectives
16.
J Diabetes Investig ; 14(6): 821-823, 2023 Jun.
Article de Anglais | MEDLINE | ID: mdl-36871284

RÉSUMÉ

Diabetes is one of the most common chronic diseases at present, and insulin pen injection therapy plays an important role in the treatment of diabetes. However, the majority of patients might reuse disposable insulin pen needles for various reasons, which leads to related complications. As far as we know, this article is the first to describe a patient whose needle remained in the right upper limb while reusing a disposable insulin injection needle for subcutaneous insulin injection with the non-dominant hand. The patient went to the doctor 1 week later. The needle moved from the lateral area of the proximal upper arm (the injection site) to the posterolateral area of the distal upper arm. The needle was then successfully removed by surgery. The reuse of disposable insulin pen needles might lead to serious complications. It is suggested to strengthen the education of people living with diabetes to help them use insulin pen needles safely.


Sujet(s)
Diabète de type 1 , Insuline , Humains , Insuline/usage thérapeutique , Diabète de type 1/traitement médicamenteux , Injections sous-cutanées , Aiguilles
17.
Chinese Journal of Biotechnology ; (12): 2126-2140, 2023.
Article de Chinois | WPRIM (Pacifique Occidental) | ID: wpr-981194

RÉSUMÉ

ω-transaminase (ω-TA) is a natural biocatalyst that has good application potential in the synthesis of chiral amines. However, the poor stability and low activity of ω-TA in the process of catalyzing unnatural substrates greatly hampers its application. To overcome these shortcomings, the thermostability of (R)-ω-TA (AtTA) from Aspergillus terreus was engineered by combining molecular dynamics simulation assisted computer-aided design with random and combinatorial mutation. An optimal mutant AtTA-E104D/A246V/R266Q (M3) with synchronously enhanced thermostability and activity was obtained. Compared with the wild- type (WT) enzyme, the half-life t1/2 (35 ℃) of M3 was prolonged by 4.8-time (from 17.8 min to 102.7 min), and the half deactivation temperature (T1050) was increased from 38.1 ℃ to 40.3 ℃. The catalytic efficiencies toward pyruvate and 1-(R)-phenylethylamine of M3 were 1.59- and 1.56-fold that of WT. Molecular dynamics simulation and molecular docking showed that the reinforced stability of α-helix caused by the increase of hydrogen bond and hydrophobic interaction in molecules was the main reason for the improvement of enzyme thermostability. The enhanced hydrogen bond of substrate with surrounding amino acid residues and the enlarged substrate binding pocket contributed to the increased catalytic efficiency of M3. Substrate spectrum analysis revealed that the catalytic performance of M3 on 11 aromatic ketones were higher than that of WT, which further showed the application potential of M3 in the synthesis of chiral amines.


Sujet(s)
Transaminases/composition chimique , Simulation de docking moléculaire , Amines/composition chimique , Acide pyruvique/métabolisme , Stabilité enzymatique
18.
Article de Chinois | WPRIM (Pacifique Occidental) | ID: wpr-981448

RÉSUMÉ

Strigolactones(SLs) are a class of sesquiterpenoids derived from the carotenoid biosynthesis pathway with the core carbon skeleton consisting of tricyclic lactone(ABC tricyclic ring) and α,β-unsaturated furan ring(D ring). SLs are widely distributed in higher plants and are symbiotic signals between plants and Arbuscular mycorrhiza(AM), which play key roles in the evolution of plant colonizing terrestrial habitats. As a new type of plant hormone, SLs possess such important biological functions as inhibiting shoot branching(tillers), regulating root architecture, promoting secondary growth, and improving plant stress resistance. Therefore, SLs have attracted wide attention. The biological functions of SLs are not only closely related to the formation of "excellent shape and quality" of Chinese medicinal materials but also have important practical significance for the production of high-quality medicinal materials. However, SLs have been currently widely studied in model plants and crops such as Oryza sativa and Arabidopsis thaliana, and few related studies have been reported on SLs in medicinal plants, which need to be strengthened. This review focused on the latest research progress in the isolation and identification, biological and artificial synthesis pathways, biosynthesis sites and transport modes, signal transduction pathways and mechanisms, and biological functions of SLs, and prospected the research on the regulation mechanism of SLs in the growth and development of medicinal plants and their related application on targeted regulation of Chinese herbal medicine production, which is expected to provide some references for the in-depth research on SLs in the field of Chinese medicinal resources.


Sujet(s)
Arabidopsis , Lactones , Plantes médicinales
19.
Chinese Journal of Burns ; (6): 114-121, 2023.
Article de Chinois | WPRIM (Pacifique Occidental) | ID: wpr-971160

RÉSUMÉ

Objective: To investigate the effects of human umbilical cord mesenchymal stem cells (hUCMSCs) combined with autologous Meek microskin transplantation on patients with extensive burns. Methods: The prospective self-controlled study was conducted. From May 2019 to June 2022, 16 patients with extensive burns admitted to the 990th Hospital of PLA Joint Logistics Support Force met the inclusion criteria, while 3 patients were excluded according to the exclusion criteria, and 13 patients were finally selected, including 10 males and 3 females, aged 24-61 (42±13) years. A total of 20 trial areas (40 wounds, with area of 10 cm×10 cm in each wound) were selected. Two adjacent wounds in each trial area were divided into hUCMSC+gel group applied with hyaluronic acid gel containing hUCMSCs and gel only group applied with hyaluronic acid gel only according to the random number table, with 20 wounds in each group. Afterwards the wounds in two groups were transplanted with autologous Meek microskin grafts with an extension ratio of 1∶6. In 2, 3, and 4 weeks post operation, the wound healing was observed, the wound healing rate was calculated, and the wound healing time was recorded. The specimen of wound secretion was collected for microorganism culture if there was purulent secretion on the wound post operation. In 3, 6, and 12 months post operation, the scar hyperplasia in wound was assessed using the Vancouver scar scale (VSS). In 3 months post operation, the wound tissue was collected for hematoxylin-eosin (HE) staining to observe the morphological changes and for immunohistochemical staining to observe the positive expressions of Ki67 and vimentin and to count the number of positive cells. Data were statistically analyzed with paired samples t test and Bonferronni correction. Results: In 2, 3, and 4 weeks post operation, the wound healing rates in hUCMSC+gel group were (80±11)%, (84±12)%, and (92±9)%, respectively, which were significantly higher than (67±18)%, (74±21)%, and (84±16)% in gel only group (with t values of 4.01, 3.52, and 3.66, respectively, P<0.05). The wound healing time in hUCMSC+gel group was (31±11) d, which was significantly shorter than (36±13) d in gel only group (t=-3.68, P<0.05). The microbiological culture of the postoperative wound secretion specimens from the adjacent wounds in 2 groups was identical, with negative results in 4 trial areas and positive results in 16 trial areas. In 3, 6, and 12 months post operation, the VSS scores of wounds in gel only group were 7.8±1.9, 6.7±2.1, and 5.4±1.6, which were significantly higher than 6.8±1.8, 5.6±1.6, and 4.0±1.4 in hUCMSC+gel group, respectively (with t values of -4.79, -4.37, and -5.47, respectively, P<0.05). In 3 months post operation, HE staining showed an increase in epidermal layer thickness and epidermal crest in wound in hUCMSC+gel group compared with those in gel only group, and immunohistochemical staining showed a significant increase in the number of Ki67 positive cells in wound in hUCMSC+gel group compared with those in gel only group (t=4.39, P<0.05), with no statistically significant difference in the number of vimentin positive cells in wound between the 2 groups (P>0.05). Conclusions: The application of hyaluronic acid gel containing hUCMSCs to the wound is simple to perform and is therefore a preferable route. Topical application of hUCMSCs can promote healing of the autologous Meek microskin grafted area in patients with extensive burns, shorten wound healing time, and alleviate scar hyperplasia. The above effects may be related to the increased epidermal thickness and epidermal crest, and active cell proliferation.


Sujet(s)
Femelle , Humains , Mâle , Jeune adulte , Adulte , Adulte d'âge moyen , Brûlures/chirurgie , Cicatrice , Éosine jaunâtre , Acide hyaluronique/usage thérapeutique , Hyperplasie , Antigène KI-67 , Études prospectives , Cordon ombilical , Vimentine
20.
China Pharmacist ; (12): 374-381, 2023.
Article de Chinois | WPRIM (Pacifique Occidental) | ID: wpr-1025892

RÉSUMÉ

Objective To optimize extraction technology for Sihuang Shaoshang ointment by orthogonal test,and establish the HPLC fingerprint of Sihuang Shaoshang ointment to provide references for the quality evaluation of the preparation.Methods Taking Sihuang Shaoshang ointment as the model drug,the fingerprints were established by HPLC method,the common peak areas were analyzed by principal component analysis,and the total factor scores were used as the evaluation index.The technological parameters such as extraction times,extraction time and liquid-solid ratio were optimized by orthogonal test,and the optimal extraction process parameters were screened out.Results The common mode of fingerprint was set up with 12 common peaks and the two principle components with the accumulative contribution rate of 84.751% extracted by principal component analysis were screened out to calculate the comprehensive scores of 9 samples.The optimal extraction process was as follows:10-fold amount of water,extracting 3 times,and extracting 2 h for each time.Conclusion The established method is simple and effective,which can provide a reference for the extraction process optimization of Sihuang Shaoshang ointment.

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