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1.
Acta Radiol ; : 2841851241228188, 2024 Feb 11.
Artigo em Inglês | MEDLINE | ID: mdl-38342993

RESUMO

BACKGROUND: Current liver magnetic resonance elastography (MRE) scans often require adjustments to driver amplitude to produce acceptable images. This could lead to time wastage and the potential loss of an opportunity to capture a high-quality image. PURPOSE: To construct a linear regression model of individualized driver amplitude to improve liver MRE image quality. MATERIAL AND METHODS: Data from 95 liver MRE scans of 61 participants, including abdominal missing volume ratio (AMVR), breath-holding status, the distance from the passive driver on the skin surface to the liver edge (Dd-l), body mass index (BMI), and lateral deflection of the passive driver with respect to the human sagittal plane (Angle α), were continuously collected. The Spearman correlation analysis and lasso regression were conducted to screen the independent variables. Multiple linear regression equations were developed to determine the optimal amplitude prediction model. RESULTS: The optimal formula for linear regression models: driver amplitude (%) = -16.80 + 78.59 × AMVR - 11.12 × breath-holding (end of expiration = 1, end of inspiration = 0) + 3.16 × Dd-l + 1.94 × BMI + 0.34 × angle α, with the model passing the F test (F = 22.455, P <0.001) and R2 value of 0.558. CONCLUSION: The individualized amplitude prediction model based on AMVR, breath-holding status, Dd-l, BMI, and angle α is a valuable tool in liver MRE examination.

2.
Osteoporos Int ; 2023 Dec 07.
Artigo em Inglês | MEDLINE | ID: mdl-38062161

RESUMO

An independent correlation between pre-RDW and 1-year mortality after surgery in elderly hip fracture can be used to predict mortality in elderly hip fracture patients and has predictive significance in anemia patients. With further research, a treatment algorithm can be developed to potentially identify patients at high risk of preoperative mortality. INTRODUCTION: Red blood cell distribution width (RDW) is an independent predictor of various disease states in elderly individuals, but its association with the prognosis of elderly hip fracture patients is controversial. This study aimed to evaluate the prognostic value of RDW in such patients, construct a prediction model containing RDW using random survival forest (RSF) and Cox regression analysis, and compare RDW in patients with and without anemia. METHODS: We retrospectively analyzed the data of elderly patients who underwent hip fracture surgery, selected the best variables using RSF, stratified the independent variables by Cox regression analysis, constructed a 1-year mortality prediction model of elderly hip fracture with RDW, and conducted internal validation and external validation. RESULTS: Two thousand one hundred six patients were included in this study. The RSF algorithm selects 12 important influencing factors, and Cox regression analysis showed that eight variables including preoperative RDW (pre-RDW) were independent risk factors for death within 1-year after hip fracture surgery in elderly patients. Stratified analysis showed that pre-RDW was still independently associated with 1-year mortality in the non-anemia group and not in the anemia group. The nomogram prediction model had high differentiation and fit, and the prediction model constructed by the total cohort of patients was also used for validation of patients in the anemia patients and obtained good clinical benefits. CONCLUSION: An independent correlation between pre-RDW and 1-year mortality after surgery in elderly hip fracture can be used to predict mortality in elderly hip fracture patients and has predictive significance in anemia patients.

3.
Molecules ; 28(24)2023 Dec 05.
Artigo em Inglês | MEDLINE | ID: mdl-38138433

RESUMO

Biotransformation of ursonic acid (1) by two fungal strains Aspergillus ochraceus CGMCC 3.5324 and Aspergillus oryzae CGMCC 3.407 yielded thirteen new compounds (4, 5, 7-10, and 13-19), along with five recognized ones. The structural details of new compounds were determined through spectroscopic examination (NMR, IR, and HR-MS) and X-ray crystallography. Various modifications, including hydroxylation, epoxidation, lactonization, oxygen introduction, and transmethylation, were identified on the ursane core. Additionally, the anti-neuroinflammatory efficacy of these derivatives was assessed on BV-2 cells affected by lipopolysaccharides. It was observed that certain methoxylated and epoxylated derivatives (10, 16, and 19) showcased enhanced suppressive capabilities, boasting IC50 values of 8.2, 6.9, and 5.3 µM. Such ursonic acid derivatives might emerge as potential primary molecules in addressing neurodegenerative diseases.


Assuntos
Aspergillus ochraceus , Aspergillus oryzae , Aspergillus ochraceus/química , Cristalografia por Raios X , Biotransformação
4.
Fitoterapia ; 171: 105688, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37757924

RESUMO

Rice husk is one of the most plentiful agriculture by-products in rice producing areas, which harbors a substantial proportion of biological metabolites, however, it has not been well studied. As an attempt to utilize it as a productive manner, phytochemical investigation on rice husk has performed and led to the isolation of three undescribed (1, 2, and 7), along with twelve known components (3-6, and 8-15). Those chemical structures were elucidated based on massive spectroscopic methods. Among them, compounds 4, 6-8, and 10-13 have been shown to act as α-glucosidase inhibitors. Notably, the most active compounds, 10/11, demonstrated comparable α-glucosidase inhibitory effect (IC50 = 1.83 ± 0.11 µg/mL) to that of 1-deoxynojirimycin (IC50 = 1.02 ± 0.16 µg/mL). For the molecular docking simulation studies, compounds 10/11 showed relative binding interactions with α-glucosidase enzyme (PDB ID: 3A4A) that similar to those reference inhibitors. Additionally, the crude extract of O. sativa demonstrated better α-glucosidase inhibitory effect to that of isolated components, with the IC50 value at 1.25 ± 0.07 µg/mL.


Assuntos
Inibidores de Glicosídeo Hidrolases , Oryza , Oryza/química , Estrutura Molecular , alfa-Glucosidases/metabolismo , Simulação de Acoplamento Molecular , Extratos Vegetais/química
5.
Chemosphere ; 335: 138962, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37230304

RESUMO

Human activities can cause zinc (Zn) contamination of aquatic environments. Zn is an essential trace metal, but effects of environmentally relevant Zn exposure on the brain-intestine axis in fish are poorly understood. Here, six-month-old female zebrafish (Danio rerio) were exposed to environmentally relevant Zn concentrations for six weeks. Zn significantly accumulated in the brain and intestine, causing anxiety-like behaviors and altered social behaviors. Zn accumulation altered levels of neurotransmitters, including serotonin, glutamate, and γ-aminobutyric acid, in the brain and intestine, and these changes were directly associated with changes in behavior. Zn caused oxidative damage and mitochondrial dysfunction, and impaired NADH dehydrogenase, thereby dysregulating the energy supply in brain. Zn exposure resulted in nucleotide imbalance and dysregulation of DNA replication and the cell cycle, potentially impairing the self-renewal of intestinal cells. Zn also disturbed carbohydrate and peptide metabolism in the intestine. These results indicate that chronic exposure to Zn at environmentally relevant concentrations dysregulates the bidirectional interaction of the brain-intestine axis with respect to neurotransmitters, nutrients, and nucleotide metabolites, thereby causing neurological disorder-like behaviors. Our study highlights the necessity to evaluate the negative impacts of chronic environmentally relevant Zn exposure on the health of humans and aquatic animals.


Assuntos
Poluentes Químicos da Água , Peixe-Zebra , Animais , Feminino , Humanos , Lactente , Peixe-Zebra/metabolismo , Zinco/metabolismo , Encéfalo/metabolismo , Nucleotídeos/metabolismo , Neurotransmissores/metabolismo , Poluentes Químicos da Água/toxicidade , Poluentes Químicos da Água/metabolismo
6.
Huan Jing Ke Xue ; 44(3): 1792-1800, 2023 Mar 08.
Artigo em Chinês | MEDLINE | ID: mdl-36922239

RESUMO

Although livestock manure serves as an effective source of nutrients for agricultural purposes, it also causes an obvious risk of contamination of heavy metals and pathogens in soil. Soil microorganisms are always considered a sensitive indicator for the change in soil quality. However, knowledge of the effects of cow manure application on soil microbial community is still scarce. Therefore, the characteristics of the soil microbial community and its influencing factors in the farmland with cow manure application were studied using dilution plate counting and high-throughput sequencing. The results showed that the ß diversity of the soil microbial community exhibited a significant difference between the cow manure application site and control site. The application of cow manure increased the relative abundance of Proteobacteria but decreased the relative abundances of Actinobacteria and Gemmatimonadetes. Furthermore, the cow manure application significantly changed the relative abundances of Sphingomonas,PLTA13, MSB-4B10, Halomonas, CCD24, Gaiella, Arthrobacter, Bacillus, and Entotheonellaceae. Both the content of soil water and actinomycete numbers were the important influencing factors of soil microbial community composition in the farmland with cow manure application. The cow manure application increased the relative abundance of pathogenic bacteria including Pseudomonas, Clostridium, and Streptococcus, which may have resulted in potential risks of pathogenic contamination for soil quality. The findings of this study are useful for understanding the effects of cow manure application on soil quality in farmland.


Assuntos
Microbiota , Solo , Animais , Feminino , Bovinos , Fazendas , Esterco/microbiologia , Agricultura , Bactérias , Microbiologia do Solo
7.
Acta Radiol ; 64(4): 1668-1675, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-36464651

RESUMO

BACKGROUND: Blood oxygen level-dependent magnetic resonance imaging (BOLD-MRI) is an imaging method used to analyze oxygenation status of the tumor. PURPOSE: To investigate the feasibility of BOLD-MRI in evaluating the efficacy of advanced cervical cancer combined with radiotherapy and chemotherapy. MATERIAL AND METHODS: This prospective study included 85 patients with advanced cervical cancer who received BOLD-MRI examination before and after concurrent chemoradiotherapy from October 2020 to December 2021. To investigate the changes of baseline R2* values and △R2* values of cervical cancers before and after treatment. RESULTS: 29 cases were complete response, 34 cases were partial response, and 22 cases showed progression. The baseline R2* values of the tumors were lower than that of the normal cervical muscle (P < 0.0001). After oxygen stimulation, the baseline R2* values of the tumors decreased (P = 0.012). After treatment, the baseline R2* values of the tumors increased (P = 0.007), and the dynamic △R2* values of the tumors decreased (P = 0.025). The baseline R2* value of the complete response was the highest (P = 0.000), the dynamic △R2* value of the complete response was the lowest (P = 0.017). CONCLUSION: BOLD-MRI can evaluate the efficacy of concurrent chemoradiotherapy for advanced cervical cancer.


Assuntos
Neoplasias do Colo do Útero , Feminino , Humanos , Neoplasias do Colo do Útero/diagnóstico por imagem , Neoplasias do Colo do Útero/terapia , Estudos Prospectivos , Saturação de Oxigênio , Imageamento por Ressonância Magnética/métodos , Quimiorradioterapia/métodos , Espectroscopia de Ressonância Magnética
8.
Ecotoxicol Environ Saf ; 248: 114303, 2022 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-36403304

RESUMO

Zinc is an essential nutrient for life, but over-accumulation can result in toxicity. Anthropogenic activities can increase zinc concentrations in aquatic environments (e.g., to ∼0.46-1.00 mg/L), which are above the safe level of 0.1 mg/L. We investigated the behavior and physiology of zebrafish (Danio rerio) in response to environment-related exposure to zinc chloride at 0.0 (Ctrl), 1.0 (ZnCl2-low) and 1.5 (ZnCl2-high) mg/L for 6 weeks (the zinc conversion ratio of zinc chloride is ∼0.48 and the nominal (measured) values were: Ctrl, 0 (∼0.01); ZnCl2-low, 0.48 (∼0.51); ZnCl2-high, 0.72 (∼0.69) mg/L). Low-zinc exposure resulted in significantly increased locomotion and fast moving behaviors, while high-zinc exposure resulted in significantly increased aggression and freezing frequency. Single cell RNA-seq of neurons, astrocytes, and oligodendrocytes of the brain revealed expression of genes related to ion transport, neuron generation, and immunomodulation that were heterogeneously regulated by zinc exposure. Astrocyte-induced central nervous system inflammation potentially integrated neurotoxicity and behavior. Integrated analyses of brain and hepatic transcriptional signatures showed that genes (and pathways) dysregulated by zinc were associated with sensory functions, circadian rhythm, glucose and lipid metabolism, and amyloid ß-protein clearance. Our results showed that environment-related zinc contamination can be heterogeneously toxic to brain cells and can disturb coordination of brain-liver physiology. This may disrupt neurobehavior and cause a neurodegeneration-like syndrome in adult zebrafish.


Assuntos
Transtornos Cronobiológicos , Peixe-Zebra , Animais , Zinco/toxicidade , Peptídeos beta-Amiloides , Encéfalo , Agressão , Fígado
9.
Med Res Rev ; 42(6): 2025-2066, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-35707917

RESUMO

Carbohydrate-based drug discovery has gained more and more attention during the last few decades. Resin glycoside is a kind of novel and complex glycolipids mainly distributed in plants of the family Convolvulaceae. Over the last decade, a number of natural resin glycosides and derivatives have been isolated and identified, and exhibited a broad spectrum of biological activities, such as cytotoxic, multidrug-resistant reversal on both microbial pathogens and mammalian cancer cells, antivirus, anticonvulsant, antidepressant, sedative, vasorelaxant, laxative, and α-glucosidase inhibitory effects, indicating their potential as lead compounds for drug discovery. A systematic review of the literature studies was carried out to summarize the chemistry and biological activity of resin glycosides from Convolvulaceae species, based on various data sources such as PubMed, Web of Science, Scopus, and Google scholar. The keyword "Convolvulaceae" was paired with "resin glycoside," "glycosidic acid," "glycolipid," or "oligosaccharide," and the references published between 2009 and June 2021 were covered. In this article, we comprehensively reviewed the structures of 288 natural resin glycoside and derivatives newly reported in the last decade. Moreover, we summarized the biological activities and mechanisms of action of the resin glycosides with pharmaceutical potential. Taken together, great progress has been made on the chemistry and biological activity of resin glycosides from Convolvulaceae species, however, more exploratory research is still needed, especially on the mechanism of action of the biological activities.


Assuntos
Convolvulaceae , Animais , Anticonvulsivantes , Convolvulaceae/química , Glicolipídeos , Glicosídeos/química , Glicosídeos/farmacologia , Humanos , Hipnóticos e Sedativos , Laxantes , Mamíferos , Oligossacarídeos , Preparações Farmacêuticas , Resinas Vegetais/química , Resinas Vegetais/farmacologia , Vasodilatadores , alfa-Glucosidases
10.
Mar Biotechnol (NY) ; 24(2): 354-365, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35305189

RESUMO

Heat shock procedure is crucial for gynogenetic manipulation leading to diploidization of the maternal genomes; however, the underlying molecular mechanism especially the transcriptomic changes during this procedure has still not been unveiled yet. Here, the artificial gynogenesis of zebrafish (Danio rerio) using inactivated sperm from rare minnow (Gobiocypris rarus) was conducted. We found that artificial gynogenetic manipulation, including pseudo-fertilization and heat shock, decreased hatching rates, whereas heat shock treatment alone had medium hatching rates. The first cleavage changed the expression of genes associated with RNA transcription and protein synthesis. A co-expression network regulated by hub genes GIT1, Sepsecs, and FLNB was significantly correlated with heat shock procedure. The cyclin family and cyclin-dependent kinase-related genes were lowly expressed in embryos from gynogenetic zebrafish, and genes involved in controlling the cell cycle and genomic stability were significantly altered by the gynogenetic treatment. Our results show the effects of artificial gynogenesis on embryos and describe changes in gene expression that suggest drastic changes take place in cell division by heat shock procedure. These findings will contribute to an understanding of the molecular basis for germplasm improving, including the purifying effect and allogynogenetic biological effect by gynogenesis.


Assuntos
Cyprinidae , Peixe-Zebra , Animais , Divisão Celular , Cyprinidae/genética , Resposta ao Choque Térmico/genética , Masculino , Espermatozoides , Peixe-Zebra/genética
11.
Sci Total Environ ; 828: 154099, 2022 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-35240190

RESUMO

Anthropogenic activities discharge zinc into aquatic ecosystems, and the effects of long-term and low-concentration zinc exposure on fish behavior are unclear. We evaluated the behavior and physiology of male zebrafish (Danio rerio) after a 6-week exposure to 1.0 or 1.5 ppm (mg/L) zinc chloride. The exposure caused anxiety-like behaviors and altered the social preferences in both exposure groups. Analysis of transcriptional changes suggested that in the brain, zinc exerted heterogenetic effects on immune and neurotransmitter functions. Exposure to 1.0 ppm zinc chloride resulted in constitutive immune dyshomeostasis, while exposure to 1.5 ppm zinc chloride impaired the neurotransmitter glutamate. In the intestine, zinc dysregulated self-renewal of intestinal cells, a potential loss of defense function. Moreover, exposure to 1.5 ppm zinc chloride suppressed intestinal immune functions and dysregulated tyrosine metabolism. These behavioral alterations suggested that the underlying mechanisms were distinct and concentration-specific. Overall, environmental levels of zinc can alter male zebrafish behaviors by dysregulating neurotransmitter and immunomodulation signatures.


Assuntos
Poluentes Químicos da Água , Peixe-Zebra , Animais , Comportamento Animal , Ecossistema , Homeostase , Masculino , Neurotransmissores/metabolismo , Fenótipo , Poluentes Químicos da Água/metabolismo , Peixe-Zebra/fisiologia , Zinco/metabolismo
12.
Chem Biodivers ; 19(1): e202100707, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34741384

RESUMO

Fifteen metabolites, including two flavonols (1-2), three lignans (3-5), and ten diterpenoids (6-15), were isolated from the leaves of Pinus yunnanensis. Among them, flavanonol (1) were identified as undescribed flavonol derivative with natural rarely B-ring fission lactone. Massive spectroscopic methods, the DP4+ probabilities and CD/ECD calculations were applied to establish the structure of component 1. Among these compounds, taxifolin (2) showed potent cytotoxicity, having IC50 values from 21.33 to 45.48 µg/mL, it also showed broad antibacterial activity against human pathogens with MIC values from 32 to 64 µg/mL.


Assuntos
Antibacterianos/química , Pinus/química , Antibacterianos/isolamento & purificação , Antibacterianos/farmacologia , Diterpenos/química , Diterpenos/isolamento & purificação , Diterpenos/farmacologia , Flavonóis/química , Flavonóis/isolamento & purificação , Flavonóis/farmacologia , Bactérias Gram-Negativas/efeitos dos fármacos , Bactérias Gram-Positivas/efeitos dos fármacos , Espectroscopia de Ressonância Magnética , Espectrometria de Massas , Conformação Molecular , Pinus/metabolismo , Extratos Vegetais/química , Folhas de Planta/química , Folhas de Planta/metabolismo
13.
Phys Rev Lett ; 127(21): 217202, 2021 Nov 19.
Artigo em Inglês | MEDLINE | ID: mdl-34860095

RESUMO

The study of the magnonic thermal Hall effect in magnets with Dzyaloshinskii-Moriya interaction (DMI) has recently drawn attention because of the underlying topology. Topological phase transitions may arise when there exist two or more distinct topological phases, and they are often revealed by a gap-closing phenomenon. In this work, we consider the magnons in honeycomb ferromagnets described by a Heisenberg Hamiltonian containing both an out-of-plane DMI and a Zeeman interaction. We demonstrate that the magnonic system exhibits temperature (or magnetic field) driven topological phase transitions due to magnon-magnon interactions. Specifically, when the temperature increases, the magnonic energy gap at Dirac points closes and reopens at a critical temperature, T_{c}. By showing that the Chern numbers of the magnonic bands are distinct above and below T_{c}, we confirm that the gap-closing phenomenon is indeed a signature for the topological phase transitions. Furthermore, our analysis indicates that the thermal Hall conductivity in the magnonic system exhibits a sign reversal at T_{c}, which can serve as an experimental probe of its topological nature. Our theory predicts that in CrI_{3} such a phenomenon exists and is experimentally accessible.

14.
Chem Biodivers ; 17(12): e2000552, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33098214

RESUMO

Chemical investigation of the secondary metabolites of the whole plant of bryophyte Hypnum plumaeforme Wilson led to the isolation of a new pimarane-type diterpenoid, momilactone F (1), along with seventeen known compounds. Their chemical structures were elucidated based on massive spectroscopic data. The allelopathic and antifungal properties were evaluated. Among them, momilactone F (1), acrenol (2),[11] momilactones A (3) and B (4) showed significant allelopathic activity against Samolus parviflorus Raf. and Lactuca sativa L. var. angustana Irish, as well as selected antifungal property against crop pathogenic fungi strains. On the other hand, 8(14)-podocarpen-13-on-18-oic acid (8) exhibited strong promoting activity on the growth of L. sativa L. var. angustana Irish. The present investigation provided new insights for developing of H. plumaeforme for further application as a potential agricultural tool.


Assuntos
Briófitas/metabolismo , Espectroscopia de Ressonância Magnética Nuclear de Carbono-13 , Estrutura Molecular , Espectroscopia de Prótons por Ressonância Magnética , Espectrometria de Massas por Ionização por Electrospray
15.
Org Lett ; 21(16): 6548-6551, 2019 08 16.
Artigo em Inglês | MEDLINE | ID: mdl-31373503

RESUMO

Evolvulins I and II (1 and 2), representing a new class of resin glycosides with an unprecedented trihydroxy aglycone unit, 3S,11R,14R-trihydroxyhexadecanoic acid (4), were isolated from the whole plants of Evolvulus alsinoides. Their structures were thoroughly characterized by extensive spectroscopic analyses as well as chemical evidence. Compound 1 exhibited the most potent cytotoxic activity against MCF-7 cells, with an IC50 value of 3.12 µM.


Assuntos
Antineoplásicos Fitogênicos/farmacologia , Convolvulaceae/química , Resinas Vegetais/química , Resinas Vegetais/farmacologia , Antineoplásicos Fitogênicos/química , Linhagem Celular Tumoral , Ensaios de Seleção de Medicamentos Antitumorais , Glicosídeos/química , Humanos , Células MCF-7 , Espectroscopia de Ressonância Magnética , Estrutura Molecular , Oligossacarídeos/química
16.
J Nat Prod ; 82(6): 1593-1598, 2019 06 28.
Artigo em Inglês | MEDLINE | ID: mdl-31181918

RESUMO

Six new glycosidic acids, arvensic acids E-J (1-6), were obtained from a glycosidic acid fraction afforded by alkaline hydrolysis of the crude resin glycosides from Convolvulus arvensis whole plants. Their structures were established from the spectroscopic data obtained and by chemical evidence. They were defined as heptasaccharides or hexasaccharides, comprising d-fucose, d-glucose, and l-rhamnose units. Compounds 1, 3, and 5 were assigned the 11 S-hydroxyheptadecanoic acid as the aglycone, while compounds 2, 4, and 6 were found to possess 11 S-hydroxyhexadecanoic acid as the aglycone. Compounds 1, 3, and 5 are the first representatives of resin glycosides with 11 S-hydroxyheptadecanoic acid as the aglycone.


Assuntos
Convolvulus/química , Glicosídeos/química , Resinas Vegetais/química , Glicosídeos/isolamento & purificação , Hidrólise , Espectroscopia de Ressonância Magnética , Estrutura Molecular
17.
Fitoterapia ; 133: 1-4, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30543983

RESUMO

As a continue investigation of the bioactive secondary metabolites from marine derived fungi, two new anthraquinone dimers (1, 2), along with three known anthraquinones (3-5) and two known xanthones (6, 7) were isolated from the marine-derived fungus Aspergillus versicolor. Their structures, including the absolute configurations, were elucidated by NMR, HRMS, and comparison with reported ones. Among them, compounds 1 and 2 were identified as anthraquinone dimers which dimerized by a rare C-O-C ether linkage, and both of them showed selective antibacterial activity against Gram-positive Staphylococcus aureus; whilst compound 6 exhibited moderate cytotoxicity against human cancer cell lines.


Assuntos
Antraquinonas/farmacologia , Antibacterianos/farmacologia , Aspergillus/química , Xantonas/farmacologia , Antraquinonas/isolamento & purificação , Antibacterianos/isolamento & purificação , Organismos Aquáticos/química , Linhagem Celular Tumoral , Humanos , Estrutura Molecular , Staphylococcus aureus/efeitos dos fármacos , Xantonas/isolamento & purificação
18.
Nat Prod Res ; 33(10): 1393-1398, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-29251999

RESUMO

Microbial transformation of 20(R)-panaxatriol by the fungus Aspergillus flavus Link AS 3.3950 was performed. Four new (1-4), along with two previously reported metabolites (5 and 6), were obtained. Their chemical structures were elucidated on the basis of extensive spectroscopic analyses. Furthermore, the inhibitory effects of those compounds on K562/ADR, Du-145, Hela, MCF-7 and HepG2 cell lines were evaluated by MTT assay. Among them, compound 15ß-hydroxy-20(R)-panaxatriol (4) exhibited selective inhibitory effects on human leukaemic progenitor cells K562/ADR through arresting cell cycle, which was associated with obvious decrease of cyclin B1, cyclin D1 and cyclin-dependent kinase (CDK) 1/2/4/6 protein expression.


Assuntos
Aspergillus flavus/metabolismo , Ginsenosídeos/metabolismo , Biotransformação , Ciclo Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Ciclina D1 , Fungos , Ginsenosídeos/farmacologia , Células HeLa , Células Hep G2 , Humanos , Células MCF-7 , Panax/metabolismo
19.
Fitoterapia ; 131: 209-214, 2018 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-30385401

RESUMO

In this study, a resin glycoside fraction with cytotoxic activity was isolated from the alcoholic extract of C. arvensis whole plants. To describe the chemical feature of the resin glycosides, the fraction was alkaline hydrolyzed and four novel glycosidic acids, named arvensic acids A-D (1-4), were isolated. Their structures were thoroughly elucidated on the basis of spectroscopic data and chemical evidences. They all possess a same heptasacharride core, consisting of one D-fucose, two L-rhamnose and four d-glucose units. The difference among these glycosidic acids was placed on the aglycone, which is 12S-hydroxypentadecanoic acid for 1, 12S-hydroxyhexadecanoic acid for 2, 3S,12S-dihydroxypentadecanoic acid for 3, and 3S,12S- dihydroxyhexadecanoic acid for 4. These aglycones are rarely found in the structures of resin glycosides and are firstly identified in the genus Convolvulus.


Assuntos
Ácidos/química , Convolvulus/química , Glicosídeos/química , Resinas Vegetais/química , Células A549 , Ácidos/isolamento & purificação , China , Glicosídeos/isolamento & purificação , Células HeLa , Humanos , Hidrólise , Células MCF-7 , Compostos Fitoquímicos/isolamento & purificação
20.
Artigo em Inglês | MEDLINE | ID: mdl-29610203

RESUMO

The obligate intracellular bacterium Chlamydia is a widespread human pathogen that causes serious problems, including (but not limited to) infertility and blindness. Our search for novel antichlamydial metabolites from marine-derived microorganisms led to the isolation of pyocyanin, a small compound from Pseudomonas aeruginosa Pyocyanin is an effective antichlamydial for all three Chlamydia spp. tested. It has a 50% inhibitory concentration (IC50) of 0.019 to 0.028 µM, which is comparable to the IC50 of tetracycline. At concentrations as low as 0.0039 µM, pyocyanin disables infectivity of the chlamydial elementary body (EB). At 0.5 µM or higher concentrations, the continuous presence of pyocyanin also inhibits chlamydial growth in the inclusion during later stages of the developmental cycle. Oxidative stress, a major known antimicrobial mechanism of pyocyanin, appears to be responsible only for the inhibition of bacterial growth and not for the disinfection of EBs. Pyocyanin is well-tolerated by probiotic vaginal Lactobacillus spp. Our findings suggest that pyocyanin is of therapeutic value for chlamydial infections and can serve as a valuable chemical probe for studying chlamydial biology.


Assuntos
Antibacterianos/farmacologia , Infecções por Chlamydia/microbiologia , Piocianina/farmacologia , Lactobacillus/efeitos dos fármacos , Testes de Sensibilidade Microbiana , Estresse Oxidativo/efeitos dos fármacos , Pseudomonas aeruginosa/efeitos dos fármacos , Pseudomonas aeruginosa/patogenicidade , Tetraciclina/farmacologia
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