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1.
Inj Prev ; 2024 Apr 04.
Artigo em Inglês | MEDLINE | ID: mdl-38575302

RESUMO

INTRODUCTION: In the USA each year, there are approximately 3400 sudden unexpected infant (<1 year of age) deaths (SUID) which occur without an obvious cause before an investigation. SUID includes the causes of death (COD) undetermined/unknown, sleep-related suffocation/asphyxia and sudden infant death syndrome (SIDS); these are often called SUID subtypes. Three common ways SUID subtypes are grouped (SUID subtype groups) include International Classification of Diseases (ICD) Codes, SUID Case Registry Categories or Child Death Review (CDR)-Assigned Causes. These groups are often used to monitor SUID trends and characteristics at the local, state and national levels. We describe and compare the characteristics of these three SUID subtype groups. DISCUSSION: SUID subtype groups are distinct and not directly interchangeable. They vary in purpose, strengths, limitations, uses, history, data years available, population coverage, assigning entity, guidance documentation and information available to assign subtypes. CONCLUSION: Making informed decisions about which SUID subtype group to use is important for reporting statistics, increasing knowledge of SUID epidemiology and informing prevention strategies.

3.
J Pharm Biomed Anal ; 243: 116115, 2024 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-38513497

RESUMO

Crocus sativus L. (C. sativus) has its stigma as the main valuable part used. With extremely low production and high prices, stigma is considered a scarce resource. As a result, its petals, considered as by-products, are often discarded, leading to significant waste. We developed a UPLC-Q-Orbitrap HRMS method for qualitative analysis of stigmas and petals and a UHPLC-QQQ-MS/MS method for simultaneous quantification of 9 characteristic active compounds for the first time, and compared their biological activity in vitro. The results indicated that a total of 63 compounds were identified in the petals and stigmas. The content of flavonoids in the petals was significantly superior to that in the stigma, and the content of quercetin in the petals was 50 times higher than that in the stigma. The results of the in vitro evaluation of biological activity indicated that both the petals (•OH: IC50=39.70 mg/mL; DPPH: IC50=28.37 mg/mL; ABTS: IC50=0.9868 mg/mL)and stigma (•OH: IC50=34.41 mg/mL; DPPH: IC50=38.99 mg/mL; ABTS: IC50=3.194 mg/mL)demonstrated comparable antioxidant activities. However, the tyrosinase inhibitory activity in petals (IC50=21.17 mg/mL) was weaker than that in stigma(IC50=1.488 mg/mL). This study provides a fast, reliable, and efficient analytical method that can be used for the quality assessment of petals as a natural resource and its related products in the food and pharmaceutical industries.


Assuntos
Antioxidantes , Benzotiazóis , Ácidos Sulfônicos , Espectrometria de Massas em Tandem , Antioxidantes/farmacologia , Flavonoides/farmacologia , Quercetina , Extratos Vegetais/farmacologia
4.
Environ Sci Pollut Res Int ; 31(16): 24567-24583, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38448771

RESUMO

The reduction of the carbon emissions of construction industry is urgent. Therefore, it is essential to accurately predict the carbon emissions of the provincial construction industry, which can support differentiation emission reduction policies in China. This paper proposes a carbon emission prediction model that optimizes the backpropagation (BP) neural network by genetic algorithm (GA) to predict carbon emission of construction industry, or "GA-BP". To begin with, the carbon emissions of construction industry in Sichuan Province from 2000 to 2020 are calculated by the emission factor method. Further, the electricity correction factor is introduced to eliminate the regional difference in electricity carbon emission coefficient. Finally, four factors are selected by the grey correlation analysis method to predict the carbon emission of construction industry in Sichuan Province from 2021 to 2025. The results show that the carbon emissions of construction industry in Sichuan Province have been trending up in the past two decades, with an average increase rate of 10.51%. The GA-BP model is a high-precision prediction model to predict carbon emissions of construction industry. The mean absolute percentage error (MAPE) of the model is only 6.303%, and its coefficient of determination is 0.853. Moreover, the carbon emissions of construction industry in Sichuan Province will reach 8891.97 million tons of CO2 in 2025. The GA-BP model can effectively predict the future carbon emissions of construction industry in Sichuan Province, which provides a new idea for the green and sustainable development of construction industry in Sichuan Province.


Assuntos
Indústria da Construção , Carbono , China , Eletricidade , Redes Neurais de Computação , Dióxido de Carbono , Desenvolvimento Econômico
5.
Anal Sci ; 40(6): 1023-1030, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38430366

RESUMO

Dopamine (DA) is a neuromodulatory molecule that plays critical roles in many biological processes. The dysfunctions of the DA system are closely associated with several nervous system diseases. Therefore, it is urgent to establish a simple and accurate method for DA analysis. In this study, an economic and accurate DA ratiometric sensor was established using dual-emission carbon dots (DE-CDs). DE-CDs were first synthesized by the one-step solvothermal method and two separate fluorescence emission peaks at 340 and 500 nm were observed under the excitation of 310 nm. In the presence of Hg2+, the fluorescence signal at 340 nm was significantly quenched, while the signal at 500 nm keeps stable. Upon adding DA, the quenched signal at 340 nm was significantly recovered, whereas the signal at 500 nm remains stable. Therefore, a novel ratiometric sensor for DA analysis was established. This method shows a good linear range from 500 nM to 100 µM, and the detection limit was calculated to be 80 nM. Moreover, this established method shows excellent specificity and could be applied in real sample analysis, showing great potential for application in clinical research.


Assuntos
Carbono , Dopamina , Pontos Quânticos , Espectrometria de Fluorescência , Dopamina/análise , Carbono/química , Pontos Quânticos/química , Limite de Detecção , Humanos
6.
Oncol Lett ; 27(4): 173, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38464336

RESUMO

Maspin is a serine protease inhibitor that is encoded by the human SERPINB5 gene. As a tumor inhibitor, it can inhibit the growth of tumor cells, increase adhesion between tumor cells and inhibit tumor angiogenesis. In the present study, a meta- and bioinformatics analysis was performed through the PubMed and China National Knowledge Infrastructure databases including entries added until up to March 20, 2023. It was found that compared with normal breast tissue, maspin expression was downregulated in breast cancer tissue. Maspin expression was negatively associated with lymph node metastasis. According to Kaplan-Meier plotter, it was found that lower maspin expression was negatively associated with the overall and distant metastasis-free survival rate of patients with estrogen receptor-positive, luminal A and grade 2 breast cancer. High expression of maspin was also positively associated with the relapse-free survival rate of patients of the luminal A subtype. Low maspin expression was positively associated with the post-progression and distant metastasis-free survival rate of the progesterone receptor-negative subtype. According to the GEPIA database, SERPINB5 mRNA expression was higher in normal than breast cancer tissues and negatively correlated with the TNM stage. High expression of maspin was also positively associated with the overall survival rate. In the UALCAN database, it was found that the mRNA and promoter methylation levels of SERPINB5 were higher in normal than in breast cancer tissues. These findings suggest that the expression of maspin may serve as a potential marker to indicate the occurrence, subsequent progression and even prognosis of breast cancer.

7.
Pract Lab Med ; 38: e00356, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38292924

RESUMO

Objective: Abnormal serum matrix metalloproteinase-9 (MMP-9) levels are closely related to the occurrence and development of many diseases. This study aimed to establish a fluorescence immunochromatography (FIC) method using the lanthanide fluorescent element europium(III) (Eu3+) for the quantitative measurement of MMP-9 in serum. Design & Methods: The FIC method for quantifying MMP-9 was optimized and established, and the FIC test strips (FICTS) were assembled and subsequently evaluated for sensitivity, specificity and precision. Furthermore, the reference interval and clinical sensitivity/specificity were estimated using clinical healthy/positive serum samples, and a commercial ELISA was used for comparison. Results: We successfully established an FIC method and prepared FICTS. The analytical sensitivity of the FICTS was 0.92 ng/mL, with a linearity range of 0-1000 ng/mL. The cross-reactivity of the 7 common serum interferents was less than 1.56%. All recoveries of the intra-array and inter-array samples ranged from 102.50% to 110.99%, and all CVs were less than 5%. The reference interval of the FICTS was >161.15 ng/mL. The clinical sensitivity was 96.00%, and the specificity was 97.5%. The results of 270 clinical serum samples were highly coincident with the clinical diagnostic results. Pearson correlation analysis and Bland‒Altman plots indicated that the FICTS and commercial ELISA results were consistent with the quantitative MMP-9 concentration. Conclusions: The designed FIC method and test strips may be suitable for point-of-care quantitative measurement of MMP-9, which provides a new method for screening for atherosclerosis, xerophthalmia, etc.

8.
Gastrointest Endosc ; 99(5): 667-675.e1, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38184117

RESUMO

BACKGROUND AND AIMS: The aim of this study was to determine if utilization of artificial intelligence (AI) in the course of endoscopic procedures can significantly diminish both the adenoma miss rate (AMR) and the polyp miss rate (PMR) compared with standard endoscopy. METHODS: We performed an extensive search of various databases, encompassing PubMed, Embase, Cochrane Library, Web of Science, and Scopus, until June 2023. The search terms used were artificial intelligence, machine learning, deep learning, transfer machine learning, computer-assisted diagnosis, convolutional neural networks, gastrointestinal (GI) endoscopy, endoscopic image analysis, polyp, adenoma, and neoplasms. The main study aim was to explore the impact of AI on the AMR, PMR, and sessile serrated lesion miss rate. RESULTS: A total of 7 randomized controlled trials were included in this meta-analysis. Pooled AMR was markedly lower in the AI group versus the non-AI group (pooled relative risk [RR], .46; 95% confidence interval [CI], .36-.59; P < .001). PMR was also reduced in the AI group in contrast with the non-AI control (pooled RR, .43; 95% CI, .27-.69; P < .001). The results showed that AI decreased the miss rate of sessile serrated lesions (pooled RR, .43; 95% CI, .20 to .92; P < .05) and diminutive adenomas (pooled RR, .49; 95% CI, .26-.93) during endoscopy, but no significant effect was observed for advanced adenomas (pooled RR, .48; 95% CI, .17-1.37; P = .17). The average number of polyps (Hedges' g = -.486; 95% CI, -.697 to -.274; P = .000) and adenomas (Hedges' g = -.312; 95% CI, -.551 to -.074; P = .01) detected during the second procedure also favored AI. However, AI implementation did not lead to a prolonged withdrawal time (P > .05). CONCLUSIONS: This meta-analysis suggests that AI technology leads to significant reduction of miss rates for GI adenomas, polyps, and sessile serrated lesions during endoscopic surveillance. These results underscore the potential of AI to improve the accuracy and efficiency of GI endoscopic procedures.

9.
New Phytol ; 241(5): 1950-1972, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38095236

RESUMO

Histone H3 lysine-4 trimethylation (H3K4me3) activating drought-responsive genes in plants for drought adaptation has long been established, but the underlying regulatory mechanisms are unknown. Here, using yeast two-hybrid, bimolecular fluorescence complementation, biochemical analyses, transient and CRISPR-mediated transgenesis in Populus trichocarpa, we unveiled in this adaptation a regulatory interplay between chromatin regulation and gene transactivation mediated by an epigenetic determinant, a PtrSDG2-1-PtrCOMPASS (complex proteins associated with Set1)-like H3K4me3 complex, PtrSDG2-1-PtrWDR5a-1-PtrRbBP5-1-PtrAsh2-2 (PtrSWRA). Under drought conditions, a transcription factor PtrAREB1-2 interacts with PtrSWRA, forming a PtrSWRA-PtrAREB1-2 pentamer, to recruit PtrSWRA to specific promoter elements of drought-tolerant genes, such as PtrHox2, PtrHox46, and PtrHox52, for depositing H3K4me3 to promote and maintain activated state of such genes for tolerance. CRISPR-edited defects in the pentamer impaired drought tolerance and elevated expression of PtrHox2, PtrHox46, or PtrHox52 improved the tolerance as well as growth in P. trichocarpa. Our findings revealed the identity of the underlying H3K4 trimethyltransferase and its interactive arrangement with the COMPASS for catalysis specificity and efficiency. Furthermore, our study uncovered how the H3K4 trimethyltransferase-COMPASS complex is recruited to the effector genes for elevating H3K4me3 marks for improved drought tolerance and growth/biomass production in plants.


Assuntos
Histonas , Populus , Histonas/metabolismo , Populus/metabolismo , Resistência à Seca , Biomassa , Cromatina , Saccharomyces cerevisiae/metabolismo
10.
Molecules ; 28(24)2023 Dec 17.
Artigo em Inglês | MEDLINE | ID: mdl-38138622

RESUMO

Carbon dots (CDs), as a rising star among fluorescent nanomaterials with excellent optical properties and fascinating dual-emission characteristics, have attracted increasing attention in sensing, bio-imaging, drug delivery, and so on. The synthesis of dual-emission CDs (DE-CDs) and the establishment of ratiometric fluorescence sensors can effectively diminish background interference and provide more accurate results than single-emission CDs. Although DE-CDs have generated increased attention in many fields, the review articles about DE-CDs are still insufficient. Therefore, we summarized the latest results and prepared this review. This review first provides an overview of the primary synthesis route and commonly used precursors in DE-CDs synthesis. Then, the photoluminescence mechanism behind the dual-emission phenomenon was discussed. Thirdly, the application of DE-CDs in metal cation detection, food safety analysis, biosensing, cell imaging, and optoelectronic devices has been extensively discussed. Finally, the main challenges and prospects for further development are presented. This review presents the latest research progress of DE-CDs synthesis and its application in ratiometric sensing; hopefully, it can help and encourage researchers to overcome existing challenges and broaden the area of DE-CDs research.

12.
Brain Inj ; 37(11): 1285-1293, 2023 09 19.
Artigo em Inglês | MEDLINE | ID: mdl-37614036

RESUMO

BACKGROUND: Ischemia/reperfusion (I/R) is a pathological process that causes severe damage. Propofol is known to alleviate I/R-related injury; however, the exact function and underlying mechanisms are not fully understood. METHODS: Using an oxygen glucose deprivation/re-oxygenation (OGD/R) method, an in vitro I/R injury model was induced. The cell viability and the level of Fe2+, glutathione synthetase (GSH), and malondialdehyde (MDA) were evaluated using kits. Luciferase reporter gene assay, chromatin immunoprecipitation, and RNA immunoprecipitation (RIP) were used to verify the interaction between molecules. The m6A level of BECN1 mRNA was determined through methylated RIP. RESULTS: Propofol-treated OGD/R models showed reduced levels of Fe2+ and MDA, while the cell viability and the level of GSH increased. Propofol inhibited ferroptosis by down-regulating HIF-1α in OGD/R-treated HT22 cells. HIF-1α is bound to the promoter region of YTHDF1 to promote its transcription, and YTHDF1 promoted ferroptosis by stabilizing the mRNA of BECN1. The suppressive effect of propofol on OGD/R-induced ferroptosis was reversed by the overexpression of YTHDF1. CONCLUSIONS: Our study revealed that the HIF-1α/YTHDF1/BECN1 axis in OGD/R-treated HT22 cells promotes ferroptosis, and administration of propofol can inhibit this axis to avoid cell death. This study provides a novel insight for the neuroprotective function of propofol.


Assuntos
Ferroptose , Propofol , Humanos , Propofol/farmacologia , Propofol/uso terapêutico , Neurônios , Morte Celular , Glucose , Proteína Beclina-1 , Proteínas de Ligação a RNA
13.
Phys Chem Chem Phys ; 25(32): 21538-21546, 2023 Aug 16.
Artigo em Inglês | MEDLINE | ID: mdl-37545397

RESUMO

Semi-hydrogenation of acetylene is of great importance for both industry and academia. High prices and limited supplements of noble metals leave room for developing base metal catalysts. Experiments revealed the atomically dispersed Cu supported by Al2O3 with excellent long-term stability and high ethylene selectivity, but the physical nature has rarely been investigated theoretically. DFT calculations and microkinetic modeling revealed that the surface OH species could stabilize Cu1/Al2-δO3 and enhance its catalytic performance. The selectivity of ethylene formation decreases with increasing copper clusters (e.g., Cu1/Al2-δO3> Cu4/Al2-δO3> Cu8/Al2-δO3), meaning that the atomically dispersed copper may be a potential candidate for acetylene semi-hydrogenation. The structures of a series of single site catalysts M1/Al2-δO3 (M = Fe, Co, Ni, Ag, Au) are similar to that of Cu1/Al2-δO3, but their performances in catalyzing acetylene semi-hydrogenation are different. M1/Al2-δO3 (M = Ag, Au) shows higher selectivity than Cu1/Al2-δO3, while M1/Al2-δO3 (M = Fe, Co, Ni) demonstrates a higher turnover frequency (TOF) of ethylene than Cu1/Al2-δO3. Moreover, our results indicate that the Ni1-Cu1/Al2-δO3 alloy shows both high activity and ethylene selectivity. The present results show a compensation between the reactivity and the selectivity, suggesting that alloys of VIIIB metals with IB metals like Ni1-Cu1/Al2-δO3 may be efficient candidate catalysts in acetylene selective hydrogenation.

14.
Food Chem ; 428: 136716, 2023 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-37413835

RESUMO

Panax notoginseng is a world-renowned tonic herb, which has been used as a characteristic food in Southwest China for hundreds of years. However, the taste of Panax notoginseng is extremely bitter and serious after tasting, and its bitter components are unknown. This manuscript proposes a new strategy for discovering bitter components of Panax notoginseng based on the integrated analysis of pharmacophore model, system separation and bitter tracing technology. Firstly, 16 potential bitter components were obtained by UPLC-Q-Orbitrap HRMS combined with virtual screening, most of which were saponins.Then, the bitter components were further separated by system component separation and 5 potential bitter components were obtained. Finally, the main contributors of bitterness in Panax notoginseng were verified to be Ginsenoside Rg1, Ginsenoside Rb1 and Ginsenoside Rd by components knock-in and fNIRS. In general, this paper is the first literature report on the relatively systematic study of bitter components in Panax notoginseng.


Assuntos
Medicamentos de Ervas Chinesas , Ginsenosídeos , Panax notoginseng , Saponinas , Paladar , Farmacóforo , Ginsenosídeos/análise , Cromatografia Líquida de Alta Pressão
15.
Biointerphases ; 18(4)2023 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-37410499

RESUMO

Horseradish peroxidase (HRP) is a hemoglobin composed of a single peptide chain that catalyzes the oxidation of various substrates such as phenol and aniline in the presence of hydrogen peroxide via its iron-porphyrin catalytic center. This enzyme is widely used in industrial phenol removal, food additives, biomedicine, and clinical test reagents due to its rapid reaction rate and obvious reaction outcomes. However, the large-scale use of HRP in industrial applications still faces numerous challenges, including activity, stability, and sustainability. This study demonstrates that when peroxidase is immobilized in zwitterionic polymer hydrogels, polycarboxybetaine (PCB) and polysulfobetaine (PSB), the properties of the enzyme are improved. PCB and PSB-embedded HRP exhibit a 6.11 and 1.53 times increase in Kcat/Km value, respectively, compared to the free enzyme. The immobilized enzyme also experiences increased activity over a range of temperatures and better tolerance to extreme pH and organic solvents, including formaldehyde. In addition, immobilized HRP exhibits excellent performance in storage and reproducibility. Remarkably, PCB-HRP still retains 80% of the initial activity after a 6-week storage period and can still attain the initial catalytic level of the free enzyme after six repeated cycles. It also removes 90% of phenol within 12 min, surpassing the current pharmacy on the market. These experimental results indicated that we have successfully designed a set of stable and efficient support substrates for horseradish peroxidase, which enhances its suitability for deployment in industrial applications.


Assuntos
Fenóis , Polímeros , Estabilidade Enzimática , Peroxidase do Rábano Silvestre/química , Reprodutibilidade dos Testes , Fenóis/química , Fenol , Enzimas Imobilizadas/química
16.
Int J Biol Macromol ; 243: 125148, 2023 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-37268079

RESUMO

Diabetes is a multifactorial disorder that increases mortality and disability due to its complications. A key driver of these complications is nonenzymatic glycation, which generates advanced glycation end-products (AGEs) that impair tissue function. Therefore, effective nonenzymatic glycation prevention and control strategies are urgently needed. This review comprehensively describes the molecular mechanisms and pathological consequences of nonenzymatic glycation in diabetes and outlines various anti-glycation strategies, such as lowering plasma glucose, interfering with the glycation reaction, and degrading early and late glycation products. Diet, exercise, and hypoglycemic medications can reduce the onset of high glucose at the source. Glucose or amino acid analogs such as flavonoids, lysine and aminoguanidine competitively bind to proteins or glucose to block the initial nonenzymatic glycation reaction. In addition, deglycation enzymes such as amadoriase, fructosamine-3-kinase, parkinson's disease protein, glutamine amidotransferase-like class 1 domain-containing 3A and terminal FraB deglycase can eliminate existing nonenzymatic glycation products. These strategies involve nutritional, pharmacological, and enzymatic interventions that target different stages of nonenzymatic glycation. This review also emphasizes the therapeutic potential of anti-glycation drugs for preventing and treating diabetes complications.


Assuntos
Diabetes Mellitus , Humanos , Diabetes Mellitus/tratamento farmacológico , Diabetes Mellitus/metabolismo , Produtos Finais de Glicação Avançada/metabolismo , Reação de Maillard , Proteínas/química , Glucose/química
17.
Oncol Lett ; 25(6): 220, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37153063

RESUMO

Malignant melanoma is one of the most common malignant tumors. Although its incidence rate is generally low among the Chinese population, it has grown rapidly in recent years. The incidence of primary malignant melanoma in the digestive tract is very low. The incidence in the esophagus and rectum are more common, while reports in the colon are only reported in <10 cases. Primary signet ring cell carcinoma of the rectum is also a rare and unique tumor. This paper reports a case of rectal malignant melanoma with signet ring cell carcinoma.

18.
Sci Rep ; 13(1): 7626, 2023 05 10.
Artigo em Inglês | MEDLINE | ID: mdl-37165051

RESUMO

Although exogenous glycine betaine (GB) and cycloleucine (Cyc) have been reported to affect animal cell metabolism, their effects on plant growth and development have not been studied extensively. Different concentrations of exogenous glycine betaine (20, 40, and 60 mmol L-1) and cycloleucine (10, 20, and 40 mmol L-1), with 0 mmol L-1 as control, were used to investigate the effects of foliar spraying of betaine and cycloleucine on growth, photosynthesis, chlorophyll fluorescence, Calvin cycle pathway, abaxial leaf burr morphology, endogenous hormones, and amino acid content in eggplant. We found that 40 mmol L-1 glycine betaine had the best effect on plant growth and development; it increased the fresh and dry weight of plants, increased the density of abaxial leaf hairs, increased the net photosynthetic rate and Calvin cycle key enzyme activity of leaves, had an elevating effect on chlorophyll fluorescence parameters, increased endogenous indoleacetic acid (IAA) content and decreased abscisic acid (ABA) content, and increased glutamate, serine, aspartate, and phenylalanine contents. However, cycloleucine significantly inhibited plant growth; plant apical dominance disappeared, plant height and dry and fresh weights decreased significantly, the development of abaxial leaf hairs was hindered, the net photosynthetic rate and Calvin cycle key enzyme activities were inhibited, the endogenous hormones IAA and ABA content decreased, and the conversion and utilization of glutamate, arginine, threonine, and glycine were affected. Combined with the experimental results and plant growth phenotypes, 20 mmol L-1 cycloleucine significantly inhibited plant growth. In conclusion, 40 mmol L-1 glycine betaine and 20 mmol L-1 cycloleucine had different regulatory effects on plant growth and development.


Assuntos
Betaína , Solanum melongena , Betaína/farmacologia , Betaína/metabolismo , Solanum melongena/metabolismo , Cicloleucina/metabolismo , Cicloleucina/farmacologia , Aminoácidos/metabolismo , Fotossíntese , Ácido Abscísico/metabolismo , Clorofila/metabolismo , Hormônios/metabolismo , Folhas de Planta/metabolismo
19.
J Vis Exp ; (193)2023 03 10.
Artigo em Inglês | MEDLINE | ID: mdl-36971441

RESUMO

Animal-derived medicines have distinctive characteristics and significant curative effects, but most of them have an obvious fishy odor, resulting in the poor compliance of clinical patients. Trimethylamine (TMA) is one of the key fishy odor components in animal-derived medicine. It is difficult to identify TMA accurately using the existing detection method due to the increased pressure in the headspace vial caused by the rapid acid-base reaction after the addition of lye, which causes TMA to escape from the headspace vial, stalling the research progress of the fishy odor of animal-derived medicine. In this study, we proposed a controlled detection method that introduced a paraffin layer as an isolation layer between acid and lye. The rate of TMA production could be effectively controlled by slowly liquefying the paraffin layer through thermostatic furnace heating. This method showed satisfactory linearity, precision experiments, and recoveries with good reproducibility and high sensitivity. It provided technical support for the deodorization of animal-derived medicine.


Assuntos
Lixívia , Animais , Cromatografia Gasosa-Espectrometria de Massas , Reprodutibilidade dos Testes , Parafina
20.
Nat Plants ; 9(1): 96-111, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36624255

RESUMO

Stem vascular cambium cells in forest trees produce wood for materials and energy. WOX4 affects the proliferation of such cells in Populus. Here we show that PtrWOX4a is the most highly expressed stem vascular-cambium-specific (VCS) gene in P. trichocarpa, and its expression is controlled by the product of the second most highly expressed VCS gene, PtrVCS2, encoding a zinc finger protein. PtrVCS2 binds to the PtrWOX4a promoter as part of a PtrWOX13a-PtrVCS2-PtrGCN5-1-PtrADA2b-3 protein tetramer. PtrVCS2 prevented the interaction between PtrGCN5-1 and PtrADA2b-3, resulting in H3K9, H3K14 and H3K27 hypoacetylation at the PtrWOX4a promoter, which led to fewer cambium cell layers. These effects on cambium cell proliferation were consistent across more than 20 sets of transgenic lines overexpressing individual genes, gene-edited mutants and RNA interference lines in P. trichocarpa. We propose that the tetramer-PtrWOX4a system may coordinate genetic and epigenetic regulation to maintain normal vascular cambium development for wood formation.


Assuntos
Câmbio , Populus , Câmbio/genética , Populus/genética , Epigênese Genética , Código das Histonas , Madeira , Regulação da Expressão Gênica de Plantas
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