RESUMO
It has long been observed that rare earth elements (REEs) regulate multiple facets of plant growth and development. However, the underlying mechanisms remain largely unclear. Here, using electron microscopic autoradiography, we show the life cycle of a light REE (lanthanum) and a heavy REE (terbium) in horseradish leaf cells. Our data indicate that REEs were first anchored on the plasma membrane in the form of nanoscale particles, and then entered the cells by endocytosis. Consistently, REEs activated endocytosis in plant cells, which may be the cellular basis of REE actions in plants. Moreover, we discovered that a portion of REEs was successively released into the cytoplasm, self-assembled to form nanoscale clusters, and finally deposited in horseradish leaf cells. Taken together, our data reveal the life cycle of REEs and their cellular behaviors in plant cells, which shed light on the cellular mechanisms of REE actions in living organisms.
Assuntos
Armoracia/metabolismo , Endocitose/fisiologia , Metais Terras Raras/metabolismo , Desenvolvimento Vegetal/fisiologia , Vesículas Transportadoras/metabolismo , Armoracia/crescimento & desenvolvimento , Flores/metabolismo , Lantânio/metabolismo , Folhas de Planta/crescimento & desenvolvimento , Folhas de Planta/metabolismo , Raízes de Plantas/crescimento & desenvolvimento , Raízes de Plantas/metabolismo , Radioisótopos , Solo , Térbio/metabolismoRESUMO
The success of guided bone regeneration (GBR) surgery depends largely on the use of GBR membranes to maintain space for bone regeneration and prevent soft tissue ingrowth. However, currently available commercial degradable GBR membranes are often limited by poor space maintenance ability and require additional suture or nail for fixation. To overcome these limitations, we developed a rapid-shaping, adhesive, and user-friendly GBR membrane (PLGA film-PGN) with long-lasting space maintenance by immersing an electrospun poly(lactide-co-glycolic acid) film in a photo-crosslinkable hydrogel composed of polyethylene glycol diacrylate, gelatin methacryloyl, and nanosilicate (PGN). The PGN hydrogel significantly improved the mechanical strength of the PLGA film-PGN and endowed it with plasticity and adhesive properties, making it more maneuverable. The maximum bending force that the PLGA film-PGN could withstand was over 55 times higher than that of the HEAL ALL film (a commonly used commercial GBR membrane). PLGA film-PGN also promoted the proliferation and osteogenic differentiation of rBMSCs. According to a critical-size rat calvarial defect model, PLGA film-PGN maintained the space within the defect area and significantly enhanced bone formation 4 weeks after the surgery. To conclude, the study provided a novel perspective on GBR membrane design and the multifunctional PLGA film-PGN membrane demonstrated great potential for bone defect reconstruction.
Assuntos
Osteogênese , Mantenedor de Espaço em Ortodontia , Ratos , Animais , Copolímero de Ácido Poliláctico e Ácido Poliglicólico , Membranas Artificiais , Regeneração Óssea , HidrogéisRESUMO
BACKGROUND: Exosomes derived from endometrial regenerative cells (ERC-Exos) can inherit the immunomodulatory function from ERCs, however, whether ERC-Exos exhibit such effect on inflammatory bowel diseases with mucosal immune dysregulation has not been explored. Insulin-like growth factor-â ¡ (IGF2) is considered to possess the potential to induce an anti-inflammatory phenotype in immune cells. In this study, the contribution of IGF2 in mediating the protective efficacy of ERC-Exos on colitis was investigated. METHODS: Lentiviral transfection was employed to obtain IGF2-specific knockout ERC-Exos (IGF2-/--ERC-Exos). Experimental colitis mice induced by dextran sulfate sodium (DSS) were divided into the phosphate-buffered saline (untreated), ERC-Exos-treated and IGF2-/--ERC-Exos-treated groups. Colonic histopathological analysis and intestinal barrier function were explored. The infiltration of CD4+ T cells and dendritic cells (DCs) were analyzed by immunofluorescence staining and flow cytometry. The maturation and function of bone marrow-derived dendritic cells (BMDCs) in different exosome administrations were evaluated by flow cytometry, ELISA and the coculture system, respectively. RESULTS: Compared with the untreated group, ERC-Exos treatment significantly attenuated DSS-induced weight loss, bloody stools, shortened colon length, pathological damage, as well as repaired the weakened intestinal mucosal barrier, including promoting the goblet cells retention, restoring the intestinal barrier integrity and enhancing the expression of tight junction proteins, while the protective effect of exosomes was impaired with the knockout of IGF2 in ERC-Exos. Additionally, IGF2-expressing ERC-Exos decreased the proportions of Th1 and Th17, increased the proportions of Treg, as well as attenuated DC infiltration and maturation in mesenteric lymph nodes and lamina propria of the colitis mice. ERC-Exos were also observed to be phagocytosed by BMDCs and IGF2 is responsible for the modulating effect of ERC-Exos on BMDCs in vitro. CONCLUSIONS: Exosomes derived from ERCs can exert a therapeutic effect on experimental colitis with remarkable alleviation of the intestinal barrier damage and the abnormal mucosal immune responses. We emphasized that IGF2 plays a critical role for ERC-Exos mediated immunomodulatory function and protection against colitis.
RESUMO
Objective: This study explores the health-related quality of life (HRQoL) scores of Chinese older adults with Cardiovascular Disease(CVD) using the EQ-5D-3L, the aim of this study is to investigate the association between health and HRQoL in older adults with CVD. Methods: The data for this study were obtained from a cross-sectional study involving older adults residing in Chinese communities The EQ-5D-3L is used to measure the HRQoL scores in the older adults with CVD. One-way analyses were conducted using the Wilcoxon rank sum test and the Kruskal-Wallis H test to assess differences between groups. A binary logistic regression model was employed to analyze the influence each variable has on the presence of "any problem" on each dimension of EQ-5D-3L in older adults with CVD. An ordinal least squares (OLS) model is used to assess the relationship between older adults with CVD and HRQoL. Results: The mean EQ-5D-3L score for older adults with CVD is 0.774. 40.0% of older adults with CVD reported problems with pain/discomfort, followed by Mobility (35.9%), Self-care (31.5%), and Anxiety/depression (17.0%). Binary logistic regression models show that financial resources were the main factor influencing the five dimensions of EQ-5D-3L. The OLS model further indicates that younger age, financial resources, and a lower number of chronic conditions among older adults with CVD are associated with higher HRQoL scores. Conclusion: Chinese older adults with CVD have low HRQoL scores. Variousfactors influence both overall HRQoL scores and scores on each EQ-5D-3L dimension. This study is helpful in enhancing society's attention to the HRQoL of older adults with CVD and taking targeted measures to improve them.
Assuntos
Doenças Cardiovasculares , Qualidade de Vida , Humanos , Idoso , Estudos Transversais , Doenças Cardiovasculares/epidemiologia , Inquéritos e Questionários , China/epidemiologiaRESUMO
Bone retention is a usual clinical problem existing in a lot of maxillofacial surgeries involving bone reconstruction and bone transplantation, which puts forward the requirements for bone adhesives that are stable, durable, biosafe, and biodegradable in wet environment. To relieve the suffering of patients during maxillofacial surgery with one-step operation and satisfying repair, herein, we developed a double-cross-linked A-O hydrogel named by its two components: [(3-Aminopropyl) methacrylamide]-co-{[Tris(hydroxymethyl) methyl] acrylamide} and oxidated methylcellulose. With excellent bone adhesion ability, it can maintain long-lasting stable underwater bone adhesion for over 14 days, holding a maximum adhesion strength of 2.32 MPa. Schiff-base reaction and high-density hydrogen bonds endow the hydrogel with strong cohesion and adhesion performance as well as maneuverable properties such as easy formation and injectability. A-O hydrogel not only presents rarely reported long-lasting underwater adhesion of hard tissue but also owns inherent biocompatibility and biodegradation properties with a porous structure that facilitates the survival of bone graft. Compared to the commercial cyanoacrylate adhesive (3 M Vetbond Tissue Adhesive), the A-O hydrogel is confirmed to be safer, more stable, and more effective in calvarial in situ bone retention model and onlay bone retention model of rat, providing a practical solution for the everyday scenario of clinical bone retention.
Assuntos
Hidrogéis , Adesivos Teciduais , Humanos , Ratos , Animais , Hidrogéis/química , Adesivos/química , Adesivos Teciduais/farmacologia , Adesivos Teciduais/química , Aderências Teciduais , CianoacrilatosRESUMO
Following the introduction of osteo-immunomodulation as a new and important strategy to enhance material osseointegration, achieving an appropriate immune response after biomaterial implantation has become a significant challenge for efficient bone repair. In this study, a nanosilicate-reinforced sodium alginate (SA) hydrogel was fabricated by introducing montmorillonite (MMT) nanoparticles. Meanwhile, an immunogenically bioactive agent, harmine (HM), was loaded and released to induce macrophage differentiation into the M2 type. The fabricated SA/MMT/HM (SMH) hydrogel exhibited improved mechanical stiffness and stability, which also efficiently promoted macrophage anti-inflammatory M2 phenotype polarization and enhanced the secretion of pro-tissue healing cytokines for inducing a favorable immunomodulatory microenvironment for the osteogenic differentiation of bone marrow stromal cells (BMSCs). Furthermore, a rat air-pouch model and a critical-size bone defect model were used and the results showed that the SMH hydrogel increased the proportion of M2 macrophages and markedly reduced local inflammation, while enhancing desirable new bone formation. Transcriptomic analysis revealed that the SMH hydrogel accelerated the M1-to-M2 transition of macrophages by inhibiting relevant inflammatory signaling pathways and activating the PI3K-AKT1 signaling pathway. Taken together, this high-intensity immunomodulatory hydrogel may be a promising biomaterial for bone regeneration and provide a valuable base and positive enlightenment for massive bone defect repair.
Assuntos
Hidrogéis , Osseointegração , Ratos , Animais , Hidrogéis/farmacologia , Osteogênese , Ratos Sprague-Dawley , Materiais Biocompatíveis/farmacologiaRESUMO
The treatment of wounds that develop on moving parts of the body, such as joints, is considered a challenge due to poor mechanical matching and secondary injury caused by continuous motion and inflammation. Herein, a stretchable, multifunctional hydrogel dressing utilizing the dual cross-linking of chitosan (CS) and acrylic acid (AA) and modified with caffeic acid (CA) and aloin (Alo) was developed. Mechanical testing demonstrated that the hydrogel possessed excellent stretching capability (of approximately 869%) combined with outstanding adhesion (about 56 kPa), contributing to its compatibility with moving parts and allowing complete coverage of wound sites without limiting joint and organ motion. Bioinformatics analysis confirmed that use of the hydrogel resulted in upregulated expression of multiple genes related to angiogenesis and cell proliferation. Furthermore, antibacterial testing indicated that the dressing suppressed the growth of Escherichia coli and methicillin-resistant Staphylococcus aureus (MRSA), providing a better microenvironment for wound healing. An in vivo wound defect model on movable skin verified that the wound healing observed with the hydrogel dressing was superior to that observed with a commercially available dressing. Taken together, the results suggest that a stretchable multifunctional hydrogel dressing represents a promising alternative wound dressing with therapeutic potential for superior healing, especially for moving parts of the body.
Assuntos
Hidrogéis , Staphylococcus aureus Resistente à Meticilina , Hidrogéis/farmacologia , Antioxidantes/farmacologia , Cicatrização , Antibacterianos/farmacologia , Escherichia coliRESUMO
OBJECTIVE: To explore the factors that influence institutional care for the disabled elderly in China and the key factors that influence individuals based on the Andersen model. DESIGN: Cross-sectional survey. SETTING: The research was conducted in 18 cities in Henan Province, China. MAIN OUTCOME MEASURES: A multistage, stratified sampling design was employed. The χ2 test was used to compare the differences in basic information of the disabled elderly. A binary Logit model was used to examine the factors influencing the willingness to institutionalise elderly people with disabilities. The determinants of willingness to care in an institution were also explored in a stratified study by gender, age and region to identify the key differences affecting institutionalisation. The Andersen model was used as the theoretical framework to infer the impact strength of each model. RESULTS: Of the 2810 disabled elderly people in Henan, China, 7.4% of the elderly had a willingness for institutional care. In the binary logistic regression analysis, whether living alone (OR (95% CI)=0.596 (0.388 to 0.916)), medical payment method (basic medical insurance for urban employees: OR (95% CI)=2.185 (1.091 to 4.377)), having mental illness (OR (95% CI)=2.078 (1.044 to 4.137)) had a statistically significant difference (p<0.05) on the impact on the willingness of the disabled elderly to receive institutional care. Validation of the fitted coefficients of the model revealed that the needs factor had the most significant effect on the enabling variable, while the predisposing factor had more minerally effect. CONCLUSIONS: Several factors influence the willingness of the disabled elderly to institutionalise. Therefore, it is recommended that relevant authorities take targeted measures to focus on the disabled elderly to identify more precise elderly care services to deal with the ageing crisis.
Assuntos
Pessoas com Deficiência , Humanos , Idoso , Estudos Transversais , Inquéritos e Questionários , China , CidadesRESUMO
Objective: To explore the relationship between ambient PM2.5 level and outpatient visits of children with respiratory diseases in a megacity, Zhengzhou, in central China. Methods: We collected daily outpatient visit data, air pollutant data, and meteorological data at the monitoring points of Zhengzhou from the time period 2018 to 2020 and used Spearman's rank correlation to analyze the correlation between children's respiratory outpatient visits and air pollutants and meteorological factors. Generalized additive models were used to analyze the association between PM2.5 exposures and children's respiratory outpatient visits. A stratified analysis was further carried out for the seasons. Results: From 2018 to 2020, the total number of outpatients with children's respiratory diseases was 79,1107, and the annual average concentrations of PM2.5, PM10, SO2, NO2, CO, and O3-8h in Zhengzhou were respectively 59.48 µg/m3, 111.12 µg/m3, 11.10 µg/m3, 47.77 µg/m3, 0.90 mg/m3 and 108.81 µg/m3. The single-pollutant model showed that the risk of outpatient visits for children with respiratory disease increased by 0.341% (95%CI: 0.274-0.407%), 0.532% (95%CI: 0.455-0.609%) and 0.233% (95%CI: 0.177-0.289%) for every 10 µg/m3 increase in PM2.5 with a 3-day lag, 1-day lag, and 1-day lag respectively for the whole year, heating period, and non-heating period. The multi-pollutant model showed that the risk of PM2.5 on children's respiratory disease visits was robust. The excess risk of PM2.5 on children's respiratory disease visits increased by 0.220% (95%CI: 0.147-0.294%) when SO2 was adjusted. However, the PM2.5 effects were stronger during the heating period than during the non-heating period. Conclusion: The short-term exposure to PM2.5 was significantly associated with outpatient visits for children's respiratory diseases. It is therefore necessary to strengthen the control of air pollution so as to protect children's health.
Assuntos
Poluentes Atmosféricos , Poluentes Ambientais , Transtornos Respiratórios , Poluentes Atmosféricos/análise , Criança , China/epidemiologia , Poluentes Ambientais/análise , Humanos , Dióxido de Nitrogênio/análise , Pacientes Ambulatoriais , Material Particulado/análiseRESUMO
Aims: To explore the structural relationship between perceived participation and autonomy among older adults with stroke and hypertension in home and community-based services (HCBSs) in the eastern coastal region of China. Design: An explorative cross-sectional study. Methods: From July to September 2021, a total of 714 respondents were reported to have stroke and hypertension, and their information was used in the analysis of this study. A multiple linear regression analysis was used to explore the factors influencing factors older adults' perceived participation and autonomy. Using the ISM model, we analyzed the factors affecting social participation in patients with stroke and hypertension and explained the logical relationships and hierarchy among the factors. Results: The mean score of perceived participation was 58.34 ± 27.57. Age, marital status, health insurance, living status, number of children, chronic diseases, sleep time, frequency of outings, and health utility value were significant factors affecting perceived participation and autonomy with stroke and hypertension patients. Among them, health insurance is the direct factor on the surface, age, number of children, chronic diseases, sleep time, frequency of outings, and health utility value are the intermediate indirect factors, and marital status and living status are the deep-rooted factors. Conclusion: By the study that the hierarchical structure provides a visualization of interrelationships and interdependences among the influencing factors of perceived participation and autonomy. It also may be a significant complement to traditional variable-entered approaches and construct an optimized multidimensional perspective of participation and autonomy. Future research should focus on optimizing the living environment of older adults with stroke and hypertension to explore the model of rehabilitative intervention and help patients successfully reintegrate into their families/societies.
Assuntos
Acidente Vascular Cerebral , Criança , Humanos , Idoso , Estudos Transversais , Inquéritos e Questionários , Participação Social , ChinaRESUMO
Objective: To investigate whether there is a curvilinear relationship between burnout and work engagement among staff in Chinese community services for the elderly. Methods: A stratified whole-group random sampling method was used to survey 244 staff members from eight communities in two cities. Data were collected using the Maslach Burnout Inventory scale (MBI) and the Utrecht Work Engagement Scale- 9 (UWES- 9). The curve estimation method explored the functional model of burnout and work engagement scales. Results: Two hundred forty-four staff members completed the survey. Burnout, depersonalization (DP), and personal accomplishment (PA) were found to be related to work engagement in a cubic function (R2 = 0.166, P < 0.05), (R2 = 0.061, P < 0.05), and (R2 = 0.2230, P < 0.05), respectively. There was no statistically significant relationship between emotional exhaustion (EE) and work engagement (P > 0.05). "Personal Accomplishment" is related to work engagement in a U-shaped curve. Conclusions: There was a cubic function relationship between burnout and work engagement, where "personal accomplishment" was related to work engagement in a U-shaped curve. Therefore, the government and related service organizations should understand the impact of different levels of burnout on work engagement and take targeted measures to alleviate burnout and improve work engagement by targeting emotions and stroke.
Assuntos
Esgotamento Profissional , Serviços de Saúde Comunitária , Engajamento no Trabalho , Idoso , Esgotamento Profissional/psicologia , Correlação de Dados , Humanos , Seguridade Social , Inquéritos e QuestionáriosRESUMO
Broad-spectrum fungicide chlorothalonil (CTN) is successively applied into intensive agriculture soil. However, the impacts of successive CTN applications on soil nitrification and related microorganisms remain poorly understood. A microcosm study was conducted to reveal the effects of successive CTN applications on soil nitrification and functional genes involved in soil nitrogen (N) cycling. The CTN at the dosages of 5 mg kg-1 dry soil (RD) and 25 mg kg-1 dry soil (5RD) was successively applied into the test soil at 7-day intervals which resulted in the accumulations of CTN residues. After 28 days of incubation, CTN residues in the RD and 5RD treatments were 3.14 and 69.7 mg kg-1 dry soil respectively. Net nitrification rates in the RD and 5RD treatments were lower than that obtained from the blank control (CK). Real-time PCR analysis revealed that AOA and AOB amoA gene abundances were significantly decreased by CTN applications. Moreover, CTN applications also discrepantly decreased the abundances of functional genes involved in soil denitrification, with the exception of nosZ gene. Principal component analysis further supported the observation that successive CTN applications could result in enhanced ecological toxicity.
Assuntos
Nitrilas/metabolismo , Ciclo do Nitrogênio , Nitrogênio/metabolismo , Solo/química , Nitrificação , Nitrilas/química , Nitrogênio/química , Reação em Cadeia da Polimerase em Tempo Real , Microbiologia do SoloRESUMO
It is difficult for polysaccharides to be directly absorbed through the intestine, which implies other utilization mechanisms involved in the bioactivity performance of polysaccharide. In this study, the multi-omics approach was applied to investigate the impacts of longan polysaccharide on mouse intestinal microbiome and the interaction between the polysaccharide-derived microbiome and host immune system. According to the result, the longan polysaccharide showed a significant improvement in the typical intestinal immunity index of mice. Meanwhile, at the taxonomy level, the intestinal microbiota from the control group and polysaccharide group were highly distinct in organismal structure. At the functional level, a significant decline in the microbial metabolites of pyruvate, butanoate fructose and mannose in the control group was found. Additionally, a significant increase was observed in the succinic acid and the short-chain fatty acid, including acetic acid, propionic acid and butyric acid, in the polysaccharide group. Furthermore, the multi-omic based network analysis indicated that the intake of longan polysaccharide resulted in the changes of the intestinal microbiota as well as the gut metabolites, which led to the enhancement of host's immune function under the stress conditions. These results indicated the polysaccharide-derived changes in intestinal microbiota were involved in the immunomodulatory activities.
Assuntos
Disbiose/prevenção & controle , Frutas/química , Imunomodulação , Malpighiaceae/química , Extratos Vegetais/uso terapêutico , Polissacarídeos/uso terapêutico , Prebióticos , Animais , Biomarcadores/metabolismo , China , Biologia Computacional , Disbiose/imunologia , Disbiose/microbiologia , Disbiose/patologia , Etnofarmacologia , Ácidos Graxos Voláteis/metabolismo , Fezes/química , Fezes/microbiologia , Fermentação , Frutas/crescimento & desenvolvimento , Microbioma Gastrointestinal/imunologia , Imunidade nas Mucosas , Mucosa Intestinal/imunologia , Mucosa Intestinal/metabolismo , Mucosa Intestinal/microbiologia , Mucosa Intestinal/patologia , Masculino , Malpighiaceae/crescimento & desenvolvimento , Medicina Tradicional , Metabolômica , Camundongos Endogâmicos C57BL , Distribuição AleatóriaRESUMO
Phosphate rock (PR) has been shown to promote plant growth and arsenic (As) uptake by As-hyperaccumulator Pteris vittata (PV). However, little is known about its behaviors in agricultural soils. In this study, impact of 50 mg kg(-1) As and/or 1.5% PR amendment on plant As accumulation and growth was investigated by growing PV for 90 d in three agricultural soils. While As amendment significantly increased plant As uptake and substantially promoted PV growth, the opposite was observed with PR amendment. Arsenic amendment increased plant frond As from 16.9-265 to 961-6017 mg kg(-1),whereas PR amendment lowered frond As to 10.2-216 mg kg(-1). The As-induced plant growth stimulation was 69-71%. While PR amendment increased plant Ca and P uptake, As amendment showed opposite results. The PV biomass was highly correlated with plant As at r = 0.82, but with weak correlations with plant Ca or P at r < 0.30. This study confirmed that 1) As significantly promoted PV growth, probably independent of Ca or P uptake, 2) PR amendment didn't enhance plant growth or As uptake by PV in agricultural soils with adequate available P, and 3) PV effluxed arsenite (AsIII) growing in agricultural soils.
Assuntos
Arsênio/toxicidade , Pteris/crescimento & desenvolvimento , Poluentes do Solo/toxicidade , Arsênio/análise , Arsenitos , Biodegradação Ambiental , Biomassa , Fosfatos/química , Desenvolvimento Vegetal/efeitos dos fármacos , Raízes de Plantas/química , Pteris/efeitos dos fármacos , Solo , Poluentes do Solo/análiseRESUMO
The impact of siderophore produced by arsenic-resistant bacterium Pseudomonas PG12 on FeAsO4 dissolution and plant growth were examined. Arsenic-hyperaccumulator Pteris vittata was grown for 7 d in 0.2-strength Fe-free Hoagland solution containing FeAsO4 mineral and PG12-siderophore or fungal-siderophore desferrioxamine B (DFOB). Standard siderophore assays indicated that PG12-siderophore was catecholate-type. PG12-siderophore was more effective in promoting FeAsO4 dissolution, and Fe and As plant uptake than DFOB. Media soluble Fe and As in PG12 treatment were 34.6 and 3.07 µM, 1.6- and 1.4-fold of that in DFOB. Plant Fe content increased from 2.93 to 6.24 g kg(-1) in the roots and As content increased from 14.3 to 78.5 mg kg(-1) in the fronds. Besides, P. vittata in PG12 treatment showed 2.6-times greater biomass than DFOB. While P. vittata fronds in PG12 treatment were dominated by AsIII, those in DFOB treatment were dominated by AsV (61-77%). This study showed that siderophore-producing arsenic-resistant rhizobacteria may have potential in enhancing phytoremediation of arsenic-contaminated soils.
Assuntos
Arsenicais/análise , Desferroxamina/química , Pseudomonas/crescimento & desenvolvimento , Pteris/crescimento & desenvolvimento , Poluentes do Solo/análise , Arsenicais/química , Arsenicais/metabolismo , Biodegradação Ambiental , Biomassa , Farmacorresistência Bacteriana , Raízes de Plantas/crescimento & desenvolvimento , Raízes de Plantas/metabolismo , Pseudomonas/metabolismo , Pteris/metabolismo , Microbiologia do Solo , Poluentes do Solo/química , Poluentes do Solo/metabolismo , SolubilidadeRESUMO
Ten vobasinyl-ibogan type bisindole alkaloids, including three new ones, tabercorines A-C (1-3), and a new natural product, 17-acetyl-tabernaecorymbosine A (4), were isolated from the twigs and leaves of Tabernaemontana corymbosa. Their structures were elucidated on the basis of spectroscopic data, and the NMR data of 17-acetyl-tabernaecorymbosine A (4) was assigned and reported for the first time. The absolute configurations of 1-4 were determined by CD exciton chirality method. All new compounds were evaluated for in vitro cytotoxicity against various human cancer cell lines. Compounds 1 and 4 showed significant inhibitory effects with IC50 values comparable to those of cisplatin.
Assuntos
Antineoplásicos Fitogênicos/química , Alcaloides Indólicos/química , Tabernaemontana/química , Antineoplásicos Fitogênicos/isolamento & purificação , Linhagem Celular Tumoral , Ensaios de Seleção de Medicamentos Antitumorais , Humanos , Alcaloides Indólicos/isolamento & purificação , Concentração Inibidora 50 , Estrutura Molecular , Folhas de Planta/químicaRESUMO
Positive and negative effects of rare earth elements (REEs) in life have been reported in many papers, but the cellular mechanisms have not been answered, especially the action sites of REEs on plasma membrane are unknown. Proteins on/in the plasma membrane perform main functions of the plasma membrane. Cerium (Ce) is the richest REEs in crust. Thus, the interaction between Ce(III) and the proteins on/in the plasma membrane, the morphology of protoplast, and the contents of nutrient elements in protoplast of horseradish were investigated using the optimized combination of the fluorescence microscopy, fluorescence spectroscopy, circular dichroism, scanning electron microscopy, and X-ray energy dispersive spectroscopy. It was found that Ce(III) at the low concentrations (10, 30 µM) could interact with proteins on/in the plasma membrane of horseradish, leading to the improvement in the structure of membrane proteins and the plasma membrane, which accelerated the intra-/extra-cellular substance exchange and further promoted the development of cells. When horseradish was treated with Ce(III) at the high concentrations (60, 80 µM), Ce(III) also could interact with the proteins on/in the plasma membrane of horseradish, leading to the destruction in the structure of membrane proteins and the plasma membrane. These effects decelerated the intra-/extra-cellular substance exchange and further inhibited the development of cells. Thus, the interaction between Ce(III) and proteins on/in the plasma membrane in plants was an important reason of the positive and negative effects of Ce(III) on plants. The results would provide some references for understanding the cellular effect mechanisms of REEs on plants.
Assuntos
Armoracia/efeitos dos fármacos , Armoracia/metabolismo , Membrana Celular/efeitos dos fármacos , Membrana Celular/metabolismo , Cério/farmacologia , Proteínas de Membrana/metabolismo , Proteínas de Plantas/metabolismo , Absorção/efeitos dos fármacos , Armoracia/citologia , Armoracia/crescimento & desenvolvimento , Transporte Biológico/efeitos dos fármacos , Membrana Celular/ultraestrutura , Células Cultivadas , Cério/efeitos adversos , Cério/metabolismo , Hormese , Proteínas de Membrana/química , Folhas de Planta/citologia , Folhas de Planta/efeitos dos fármacos , Folhas de Planta/crescimento & desenvolvimento , Folhas de Planta/metabolismo , Proteínas de Plantas/química , Estabilidade Proteica/efeitos dos fármacos , Estrutura Secundária de Proteína/efeitos dos fármacos , Protoplastos/citologia , Protoplastos/efeitos dos fármacos , Protoplastos/metabolismo , Protoplastos/ultraestrutura , Plântula/citologia , Plântula/efeitos dos fármacos , Plântula/crescimento & desenvolvimento , Plântula/metabolismo , Oligoelementos/metabolismoRESUMO
Lanthanum (La) is an important rare earth element in the ecological environment of plant. The proteins on the plasma membrane control the transport of molecules into and out of cell. It is very important to investigate the effect of La(III) on the proteins on the plasma membrane in the plant cell. In the present work, the interaction between La(III) and proteins on the plasma membrane of horseradish was investigated using optimization of the fluorescence microscopy and fluorescence spectroscopy. It is found that the fluorescence of the complex system of protoplasts and 1-aniline Kenai-8-sulfonic acid in horseradish treated with the low concentration of La(III) is increased compared with that of the control horseradish. The opposite effect is observed in horseradish treated with the high concentration of La(III). These results indicated that the low concentration of La(III) can interact with the proteins on the plasma membrane of horseradish, causing the improvement in the structure of proteins on the plasma membrane. The high concentration of La(III) can also interact with the proteins on the plasma membrane of horseradish, leading to the destruction of the structure of proteins on the plasma membrane. We demonstrate that the proteins on the plasma membrane are the targets of La(III) action on plant cell.