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1.
J Appl Microbiol ; 134(8)2023 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-37580141

RESUMO

AIM: This study evaluated the phylogenetic diversity, plant growth promotion capacity, antifungal activity, and biocontrol potential of culturable actinobacterial endophytes isolated from the medicinal plant Aconitum carmichaelii Debeaux. METHODS AND RESULTS: Isolation of actinobacteria from healthy A. carmichaelii plants was carried out on six different media. Full-length 16S rRNA gene was amplified by PCR from the genomic DNA of each strain. Indole-3-acetic acid and siderophore production were quantitatively assessed by the Salkowski and Chrome Azurol S methods, respectively. Rice seeds germination and seedling growth were employed to evaluate plant growth promotion capacities of candidate strains. Dual-culture assay and pot experiments were performed to investigate the antifungal and biocontrol potential of isolates. We obtained 129 actinobacterial isolates from A. carmichaelii, and they belonged to 49 species in 7 genera. These strains exhibited diverse plant growth promotion ability, among which one strain significantly enhanced rice seeds germination, while 31 strains significantly facilitated rice seedling growth. SWUST-123 showed strong antifungal activity against four pathogens in vitro and was most compatible with Qingchuan cultivar. SWUST-123 reduced around 40% of southern blight disease occurrence compared to blank control treatment. . CONCLUSION: Aconitum carmichaelii harbored genetically diverse actinobacterial endophytes exhibiting diverse plant growth promotion and antifungal potential, some of which can be served as good candidates for biofertilizers and biocontrol agents.


Assuntos
Aconitum , Actinobacteria , Actinobacteria/genética , Filogenia , RNA Ribossômico 16S/genética , Antifúngicos/farmacologia , Bactérias , Plântula/genética , Variação Genética , Endófitos , Raízes de Plantas/microbiologia
2.
J Basic Microbiol ; 63(3-4): 454-468, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36504130

RESUMO

Aconitum carmichaelii Debx. is famous for the bioactive aconitum alkaloids as traditional Chinese medicine. Endophytic bacteria play vital roles in plant growth, health, and the production of secondary metabolites such as alkaloids. In this study, we employed 16 S rRNA amplicon high-throughput sequencing to determine the root endophytic bacterial community of A. carmichaelii Debx. collected from three main producing areas including the geo-authentic area in China, high performance liquid chromatography to measure the contents of six bioactive alkaloids and correlation analysis to explore the relationship among environmental factors, alkaloids contents, and endophytic bacterial community. The results indicated that the root core microbiota of A. carmichaelii Debx. was dominated by Proteobacteria, Bacteroidetes, Firmicutes, and Actinobacteria. Root endophytic bacterial community in the geo-authentic area was distinct from the other two regions. Soil nitrogen contents, organic matter, and temperature were the main factors contributing to the endophytic bacterial community structure. Significant correlation was found between alkaloids contents and some bacterial genera. Particularly, the abundance of Lactobacillus was positively correlated with the contents of benzoyl-mesaconitine and benzoyl-aconine. This study provided the first insight into the root endophytic bacterial community composition of A. carmichaelii Debx., and can direct further isolation of functional bacterial strains.


Assuntos
Aconitum , Alcaloides , Aconitum/química , Raízes de Plantas , Alcaloides/análise , Alcaloides/química , Bactérias , China
3.
J Environ Manage ; 325(Pt B): 116432, 2023 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-36274337

RESUMO

Maintaining humidification and inhibiting nitrogen losses during vermicomposting process have emerged to be key factors for high-quality productions. Previous data have showed outstanding functions of biochar addition in improving vermicomposting quality. In this study, the influence of bamboo biochar (BB) and rice husk biochar (RHB) addition on compost maturity, humification and nitrogen loss was evaluated in the vermicomposting of cattle manure and maize straw. Results revealed that BB or RHB amendment improved organic matter decomposition, enhanced humification and maturity of compost, particularly in the 10% BB treatment, which exerted the highest humic acids content and GI value. Furthermore, BB or RHB addition significantly reduced nitrogen losses, in which the volatilization of NH3 and N2O were reduced by 24.93%-66.23% and 14.91%-55.12%. The fewest nitrogen loss was detected in the treatment of 10% BB. Biochar inhibited nirK, nirS but promoted AOB-amoA, nosZ expression; fewer N2O producing bacteria (Pseudomonas, Devosia, Luteimonas genus) were observed in the biochar treatment, and thereby decreased the N2O emission. Therefore, 10% BB addition for co-vermicomposting cattle manure and maize straw is an efficient way to increase humification, maturity, and reduce nitrogen loss, and future applications following this strategy is believed to generate better productions.


Assuntos
Compostagem , Oryza , Sasa , Bovinos , Animais , Esterco , Carvão Vegetal/metabolismo , Nitrogênio/metabolismo , Zea mays/metabolismo , Solo , Oryza/metabolismo
4.
Biomed Eng Online ; 20(1): 67, 2021 Jul 03.
Artigo em Inglês | MEDLINE | ID: mdl-34217312

RESUMO

Hepatocellular carcinoma (HCC) is currently the sixth most common malignancy and the second major cause of tumor-related deaths in the world. This study aimed to investigate the role of cleavage and polyadenylation factor-6 (CPSF6) and B-cell translocation gene 2 (BTG2) in regulating the glycolysis and apoptosis in HCC cells. The RNA and protein expression of CPSF6 and BTG2 in normal hepatocyte and HCC were, respectively, detected by reverse transcription quantitative real-time polymerase chain reaction (RT-qPCR) analysis and Western blot analysis. The viability and apoptosis of transfected Huh-7 cells were, respectively, analyzed by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay and terminal deoxynucleotidyl transferase (TdT) dUTP Nick-End Labeling (TUNEL) assay. The expression of apoptosis-related proteins and HK-2 in transfected Huh-7 cells was also detected by Western blot analysis. The levels of glucose and lactate in the culture supernatant of transfected Huh-7 cells were, respectively, detected with the glucose assay kit and lactate assay kit. The interaction of CPSF6 and BTG2 was confirmed by RNA binding protein immunoprecipitation (RIP) assay. As a result, CPSF6 expression was increased while BTG2 expression was decreased in Huh-7 cells. Interference with CPSF6 suppressed the viability and glycolysis, and promoted the apoptosis of Huh-7 cells. Furthermore, CPSF6 interacted with BTG2 and interference with CPSF6 upregulated the BTG2 expression and inhibited the protein kinase B (AKT)/extracellular signal-regulated kinase (ERK)/nuclear factor (NF)-κB pathway. Interference with BTG2 could partially reverse the above cell changes caused by interference with CPSF6. In conclusion, CPSF6 inhibited the BTG2 expression to promote glycolysis and suppress apoptosis in HCC cells by activating AKT/ERK/NF-κB pathway.


Assuntos
Carcinoma Hepatocelular , Proteínas Imediatamente Precoces , Neoplasias Hepáticas , Apoptose , Carcinoma Hepatocelular/genética , Proteínas de Transporte , Linhagem Celular Tumoral , Proliferação de Células , Glicólise , Humanos , Proteínas Imediatamente Precoces/genética , Proteínas Imediatamente Precoces/metabolismo , Neoplasias Hepáticas/genética , RNA , Proteínas Supressoras de Tumor/genética , Proteínas Supressoras de Tumor/metabolismo , Fatores de Poliadenilação e Clivagem de mRNA
5.
J Anesth ; 34(4): 519-526, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32342186

RESUMO

PURPOSE: To investigate the impact of menstrual cycle on patients undergoing gynecological endoscopic surgery. PATIENTS AND METHODS: 220 patients scheduled for gynecological endoscopic surgery under general anesthesia were selected. The patients were divided into three groups based on 3 phases of menstrual cycle which are the follicular phase (Group F), ovulatory phase (Group O) or luteal phase (Group L). It is based on their duration of menstruation and the last day of menstrual bleeding from the date of surgery. Primary outcomes were the incidences of early and late postoperative nausea and vomiting (PONV) in the three patient groups. Preoperative venous blood was taken to determine the estrogen and progesterone levels of the patients. RESULTS: A total of 207 patients were enrolled. The incidence of early PONV was highest in group O (22.22% vs 43.33% vs 17.86%, P < 0.01). Multivariate logistic regression showed that menstrual cycle (P < 0.01) and sufentanil dosage (P < 0.05) were independent risk factors for early PONV, menstrual cycle (P = 0.03) and intraoperative hypotension (P = 0.03) were independent risk factors for late PONV. After the propensity matching, the incidences of early and late PONV in group O were both higher than that in other two groups (19.23% vs 44.68% vs 16.90%, P < 0.01; 53.80% vs 72.34% vs 45.07%, P = 0.01). CONCLUSION: The incidence of PONV after gynecological endoscopic surgery was different in patients with different menstrual cycles, with the highest incidence in ovulation.


Assuntos
Anestesia Geral , Náusea e Vômito Pós-Operatórios , Anestesia Geral/efeitos adversos , Feminino , Procedimentos Cirúrgicos em Ginecologia/efeitos adversos , Humanos , Ciclo Menstrual , Náusea e Vômito Pós-Operatórios/epidemiologia , Sufentanil
6.
New Phytol ; 223(3): 1505-1515, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-31059123

RESUMO

A complex network of pathways coordinates nodulation and epidermal root hair infection in the symbiotic interaction between rhizobia and legume plants. Whereas nodule formation was known to be autoregulated, it was so far unclear whether a similar control is exerted on the infection process. We assessed the capacity of Medicago plants nodulated by Sinorhizobium meliloti to modulate root susceptibility to secondary bacterial infection or to purified Nod factors in split-root and volatile assays using bacterial and plant mutant combinations. Ethylene implication in this process emerged from gas production measurements, use of a chemical inhibitor of ethylene biosynthesis and of a Medicago mutant affected in ethylene signal transduction. We identified a feedback mechanism that we named AOI (for Autoregulation Of Infection) by which endosymbiotic bacteria control secondary infection thread formation by their rhizospheric peers. AOI involves activation of a cyclic adenosine 3',5'-monophosphate (cAMP) cascade in endosymbiotic bacteria, which decreases both root infectiveness and root susceptibility to bacterial Nod factors. These latter two effects are mediated by ethylene. AOI is a novel component of the complex regulatory network controlling the interaction between Sinorhizobium meliloti and its host plants that emphasizes the implication of endosymbiotic bacteria in fine-tuning the interaction.


Assuntos
Etilenos/metabolismo , Medicago truncatula/microbiologia , Doenças das Plantas/microbiologia , Raízes de Plantas/microbiologia , Sinorhizobium meliloti/fisiologia , Simbiose , Proteínas de Bactérias/metabolismo , Modelos Biológicos , Epiderme Vegetal/microbiologia , Nodulação , Compostos Orgânicos Voláteis/metabolismo
7.
J Bacteriol ; 200(11)2018 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-29531182

RESUMO

An ongoing signal exchange fine-tunes the symbiotic interactions between rhizobia and legumes, ensuring the establishment and maintenance of mutualism. In a recently identified regulatory loop, endosymbiotic Sinorhizobium meliloti exerts negative feedback on root infection in response to unknown plant cues. Upon signal perception, three bacterial adenylate cyclases (ACs) of the inner membrane, namely, CyaD1, CyaD2, and CyaK, synthesize the second messenger cAMP, which, together with the cAMP-dependent Clr transcriptional activator, activates the expression of genes involved in root infection control. The pathway that links signal perception at the surface of the cell to cytoplasmic cAMP production by ACs was thus far unknown. Here we first show that CyaK is the cognate AC for the plant signal, called signal 1, that was observed previously in mature nodule and shoot extracts. We also show that inactivation of the gene immediately upstream of cyaK, nsrA (smb20775), which encodes a ß-barrel protein of the outer membrane, abolished signal 1 perception ex planta, whereas nsrA overexpression increased signal 1 responsiveness. Inactivation of the nsrA gene abolished all Clr-dependent gene expression in nodules and led to a marked hyperinfection phenotype on plants, similar to that of a cyaD1 cyaD2 cyaK triple mutant. We suggest that the NsrA protein acts as the (co)receptor for two signal molecules, signal 1 and a hypothetical signal 1', in mature and young nodules that cooperate in controlling secondary infection in S. meliloti-Medicago symbiosis. The predicted topology and domain composition of the NsrA protein hint at a mechanism of transmembrane signaling.IMPORTANCE Symbiotic interactions, especially mutualistic ones, rely on a continuous signal exchange between the symbionts. Here we report advances regarding a recently discovered signal transduction pathway that fine-tunes the symbiotic interaction between S. meliloti and its Medicago host plant. We have identified an outer membrane protein of S. meliloti, called NsrA, that transduces Medicago plant signals to adenylate cyclases in the inner membrane, thereby triggering a cAMP signaling cascade that controls infection. Besides their relevance for the rhizobium-legume symbiosis, these findings shed light on the mechanisms of signal perception and transduction by adenylate cyclases and transmembrane signaling in bacteria.


Assuntos
Proteínas de Bactérias/metabolismo , Medicago truncatula/microbiologia , Transdução de Sinais , Sinorhizobium meliloti/fisiologia , Simbiose , Adenilil Ciclases/genética , Adenilil Ciclases/metabolismo , Proteínas de Bactérias/genética , AMP Cíclico/metabolismo , Proteínas de Membrana/genética , Proteínas de Membrana/metabolismo , Modelos Biológicos , Mutação , Fenótipo , Sinorhizobium meliloti/genética
8.
Bull Math Biol ; 80(10): 2633-2651, 2018 10.
Artigo em Inglês | MEDLINE | ID: mdl-30083966

RESUMO

There is evidence showing that vertical transmission of dengue virus exists in Aedes mosquitoes. In this paper, we propose a deterministic dengue model with vertical transmission in mosquitoes by including aquatic mosquitoes (eggs, larvae and pupae), adult mosquitoes (susceptible, exposed and infectious) and human hosts (susceptible, exposed, infectious and recovered). We first analyze the existence and stability of disease-free equilibria, calculate the basic reproduction number and discuss the existence of the disease-endemic equilibrium. Then, we study the impact of vertical transmission of the virus in mosquitoes on the spread dynamics of dengue. We also use the model to simulate the reported infected human data from the 2014 dengue outbreak in Guangdong Province, China, carry out sensitivity analysis of the basic reproduction number in terms of the model parameters, and seek for effective control measures for the transmission of dengue virus.


Assuntos
Dengue/epidemiologia , Dengue/transmissão , Surtos de Doenças , Modelos Biológicos , Aedes/virologia , Animais , Número Básico de Reprodução , China/epidemiologia , Simulação por Computador , Dengue/prevenção & controle , Vírus da Dengue , Surtos de Doenças/prevenção & controle , Surtos de Doenças/estatística & dados numéricos , Interações Hospedeiro-Patógeno , Humanos , Transmissão Vertical de Doenças Infecciosas , Conceitos Matemáticos , Mosquitos Vetores/virologia
9.
J Nanosci Nanotechnol ; 18(8): 5502-5510, 2018 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-29458603

RESUMO

Elimination of pollutants from water is one of the greatest challenges in resolving global environmental issues. Herein, we report a high-surface-area mesoporous g-C3N4 nanosheet with remarkable high adsorption capacity and photocatalytic performance, which is prepared through directly polycondensation of urea followed by a consecutive one-step thermal exfoliation strategy. This one-pot method to prepare mesoporous g-C3N4 nanosheet is facile and rapid in comparison with others. The superior adsorption capacity of the fabricated mesoporous g-C3N4 nanostructures is demonstrated by a model organic pollutant-methylene blue (MB), which is up to 72.2 mg/g, about 6 times as that of the largest value of various g-C3N4 adsorbents reported so far. Moreover, this kind of porous g-C3N4 nanosheet exhibits high photocatalytic activity to MB and phenol degradation. Particularly, the regenerated samples show excellent performance of pollutant removal after consecutive adsorption/degradation cycles. Therefore, this mesoporous g-C3N4 nanosheet may be an attractive robust metal-free material with great promise for organic pollutant elimination.

10.
J Theor Biol ; 369: 1-12, 2015 Mar 21.
Artigo em Inglês | MEDLINE | ID: mdl-25596515

RESUMO

In a previous study we noticed that there might be co-infections of HBV and HIV by comparing incidence rates of these two diseases in China. The comparisons between the incidence data of HBV and sexually transmitted diseases (including AIDS, HIV, syphilis and gonorrhea) in China demonstrate that sexual transmission is an important route of spread of HBV in China. On the basis of this fact, in this paper we propose a compartmental model including under-aged children, male adults, and female adults. The effect of sexual transmission on the spread and prevalence of HBV in China is studied. The model is employed to simulate the HBV incidence data reported by the Chinese Center for Disease Control and Prevention for under-aged children, adult males, and adult females, respectively. The sensitivity analysis of the basic reproduction number indicates that it is important and crucial to increase the immunization rate for both under-aged children and adults in order to control the transmission of HBV in China. Our study suggests that effective control measures for hepatitis B in China include enhancing public education and awareness about hepatitis B virus, particularly about the fact that hepatitis B is a sexually transmitted disease, and increasing the immunization rate for both under-aged children and adults, especially for those groups of high risk.


Assuntos
Vírus da Hepatite B/fisiologia , Hepatite B/transmissão , Hepatite B/virologia , Modelos Biológicos , Infecções Sexualmente Transmissíveis/transmissão , Infecções Sexualmente Transmissíveis/virologia , Adulto , Número Básico de Reprodução , Criança , China/epidemiologia , Simulação por Computador , Feminino , Hepatite B/epidemiologia , Hepatite B/prevenção & controle , Humanos , Masculino , Infecções Sexualmente Transmissíveis/epidemiologia , Infecções Sexualmente Transmissíveis/prevenção & controle , Vacinação/estatística & dados numéricos
11.
Chin J Cancer ; 34(4): 184-8, 2015 Apr 08.
Artigo em Inglês | MEDLINE | ID: mdl-25963193

RESUMO

INTRODUCTION: Metabolic syndrome (MS) is associated with several cancers, but it is not clear whether MS affects the prognosis of tongue squamous cell carcinoma (TSCC). This study aimed to evaluate the prognostic value of MS in TSCC. METHODS: Clinical data from 252 patients with TSCC who were initially treated at the Sun Yat-sen University Cancer Center between April 1998 and June 2011 were collected, and the associations between MS and clinicopathologic factors were retrospectively analyzed. Prognostic outcomes were examined by Kaplan-Meier analysis and Cox regression analysis. RESULTS: Of the 252 patients, 48 were diagnosed with MS. MS was associated with early N category in TSCC (P < 0.001). The patients with MS showed longer survival than those without MS (P = 0.028). MS was an independent prognostic factor for patients with TSCC. CONCLUSIONS: MS is associated with early N category in TSCC. It is an independent prognostic factor for better survival in patients with TSCC.


Assuntos
Carcinoma de Células Escamosas , Síndrome Metabólica , Prognóstico , Neoplasias da Língua , Humanos , Estimativa de Kaplan-Meier , Mortalidade , Estudos Retrospectivos
12.
J Food Sci Technol ; 52(12): 8196-203, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26604394

RESUMO

Black pepper extracts reportedly inhibit food spoilage and food pathogenic bacteria. This study explored the antimicrobial activity of black pepper chloroform extract (BPCE) against Escherichia coli and Staphylococcus aureus. The antibacterial mechanism of BPCE was elucidated by analyzing the cell morphology, respiratory metabolism, pyruvic acid content, and ATP levels of the target bacteria. Scanning electron micrographs showed that the bacterial cells were destroyed and that plasmolysis was induced. BPCE inhibited the tricarboxylic acid pathway of the bacteria. The extract significantly increased pyruvic acid concentration in bacterial solutions and reduced ATP level in bacterial cells. BPCE destroyed the permeability of the cell membrane, which consequently caused metabolic dysfunction, inhibited energy synthesis, and triggered cell death.

13.
Cardiovasc Diagn Ther ; 14(3): 367-376, 2024 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-38975006

RESUMO

Background: Single-branched stent grafts and the chimney technique are widely used in the treatment of type B aortic dissection (TBAD). The main objective of this study was to compare the outcomes of single-branched stent grafts and the chimney technique in the treatment of TBAD. Methods: From January 2019 to December 2021, the retrospective cohort study contained a cohort of 91 patients with TBAD undergoing thoracic endovascular aortic repair (TEVAR) using single-branched stent grafts and the chimney technique. Group A included 55 patients treated with single-branched covered stents, and Group B included 36 patients treated with the chimney technique. We compared the effects of the procedures on peri-/post-operative outcomes between the two groups. The primary endpoint is clinical death, and the secondary endpoints include the patency of branch stents, the incidence of cerebral infarction, false lumen thrombosis, and the proportion of paraplegia. Results: For the baseline data, the two groups of patients show no differences in terms of age, gender, and associated symptoms. All procedures were successfully performed in both groups. The median follow-up period was 17.6 months (range, 10-34 months). During TEVAR, 5 (9.1%) type I endoleaks occurred in group A, and 11 (30.6%) occurred in group B (P<0.05). During follow-up, there were 2 cases (3.6%) of paraplegia and 1 case (1.8%) of cerebral infarction in Group A, while Group B had 1 case (2.8%) of paraplegia. Three patients in group B reported retrograde type A aortic dissection (RTAD), and 1 of them died (2.8%); however, there were no RTAD cases in group A. Complete thrombosis of the false lumen in the thoracic aorta was observed in 45.5% (25/55) of patients in group A and in 41.7% (15/36) in group B (P=0.72). No significant difference in the thrombosis-volume ratio in the whole false lumen was found during follow-up between group A (81.0%±2.9%) and group B (81.8%±2.6%; P=0.23). Conclusions: Branched stent grafts can be used in cases with insufficient proximal landing zones and reduce the occurrence of type 1 endoleak compared to the chimney technique. This may help to prevent RTAD. Further research, including more cases and longer follow-up periods, is needed to substantiate these results.

14.
World J Microbiol Biotechnol ; 29(12): 2303-15, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-23749221

RESUMO

Leucaena leucocephala was introduced into Panxi, Sichuan, China, in the 1980s and 1990s for afforestation and preventing water loss and soil erosion in this area. The co-introduction of rhizobial symbionts of introduced plants has drawn attention since they may influence local soil communities. We studied the phylogenetic position of the L. leucocephala isolates and assessed if the rhizobia were introduced together with the host to Panxi, Sichuan, China. The glnII and atpD genes of fifteen representative isolates were sequenced and analyzed, and applied multilocus sequence analyses in which the housekeeping genes recA, glnII and atpD were included. Furthermore, we estimated the within species diversity directly with 23S rDNA and IGS RFLP and indirectly through phenotypic analysis of forty L. leucocephala isolates. The isolates represented seven species and 38 diversified strains in the genera Ensifer, Mesorhizobium, Bradyrhizobium and Rhizobium. The within species diversity of the Ensifer isolates was large, proposing a potential to occupy novel niches. There was not conclusive evidence to show that any of the strains would have been co-introduced with L. leucocephala. On the contrary, we came to a conclusion that the possible introduction should not be inferred from sequence data alone.


Assuntos
Fabaceae/microbiologia , Genes Bacterianos , Rhizobium/classificação , Rhizobium/genética , Animais , Bradyrhizobium/classificação , Bradyrhizobium/genética , Bradyrhizobium/isolamento & purificação , China , DNA Bacteriano/genética , DNA Ribossômico/genética , Variação Genética , Espécies Introduzidas , Mesorhizobium/classificação , Mesorhizobium/genética , Mesorhizobium/isolamento & purificação , Fenótipo , Filogenia , Polimorfismo de Fragmento de Restrição , RNA Ribossômico 16S/genética , Rhizobium/isolamento & purificação , Microbiologia do Solo , Simbiose
15.
Environ Sci Pollut Res Int ; 30(36): 85139-85153, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37380857

RESUMO

Biochar has widely used in soil pollution remediation due to its advantages of high efficiency and environmental sustainability. Dissolved organic matter (DOM) released by biochar plays a non-negligible role in the migration and transformation of pollutants in environment, and its composition was regarded as main impact factor. In this study, 28 biochar were investigated to detect the effect of pyrolysis temperature and feedstock on DOM content and components. Results showed that the content of DOM released from biochar at low pyrolysis temperatures (300-400 ℃) was higher than that from high pyrolysis temperatures (500-600 ℃). In addition, the specific UV-Visible absorbance at 254 nm (SUVA254) results expressed that DOM from peanut shell biochar (PSBC), rice husk biochar (RHBC) and bamboo biochar (BBC) had higher humification at high temperatures. Moreover, one fulvic acid-like (C2) and two humic acid-like (C1, C3) substances were main fluorescent components of biochar-derived DOM identified by parallel factor analysis based on excitation emission matrices fluorescence spectroscopies (EEM-PARAFAC). With the increase of pyrolysis temperature, humic acid substances content gradually decreased. The correlation analysis results revealed that pyrolysis temperatures and O/C, H/C, DOM content, the biological index (BIX), humification index (HIX), C1% and C3% was negatively correlated (p < 0.001). Thus, the pyrolysis temperatures take important roles in composition of DOM released from biochar, and this research would provide a reference for the application of biochar in the environment.


Assuntos
Carvão Vegetal , Sasa , Temperatura , Substâncias Húmicas/análise , Matéria Orgânica Dissolvida , Pirólise , Espectrometria de Fluorescência/métodos
16.
Int J Pharm ; 639: 122944, 2023 May 25.
Artigo em Inglês | MEDLINE | ID: mdl-37044226

RESUMO

To revise the emission of curcumin (Cur) from "off" to "on", poly (D, L-lactide-co-glycolide) acid (PLGA) nanoparticles loaded with Cur were embedded in a polyvinyl alcohol (PVA) emulsifier (named Cur@PLGA-NPs). First, the emission intensities of different nanoformulations, including liposomes, bovine serum albumin (BSA) nanoparticles, and PLGA nanoparticles, were examined to discover the most effective carriers for Cur luminescence. As a result, Cur@PLGA-NPs exhibited the highest fluorescence intensity due to aggregation-induced emission (AIE), with quantum yields of 23.78% in aqueous solution and 21.52% in the solid state. According to X-ray diffraction (XRD) data, Cur@PLGA-NPs existed in the amorphous state, with a size of 217.2 ± 5.2 nm, an encapsulation efficiency (EE) of 69.98%, and a drug loading efficiency (LE) of 1.37%. The intramolecular interactions, which included hydrophobic interactions, electrostatic interactions, π-π interactions and solvatochromic effects, stabilized the chromophore cluster of Cur@PLGA-NPs in terms of nanoparticle formulation. Compared with free Cur, Cur@PLGA-NPs sensitized CT26 cells more efficiently with an IC50 value of 16.9 µmol/L and an apoptotic rate of 17.20% at 10 µmol/L Cur. Because of the robust fluorescence emission based on AIE, Cur@PLGA-NPs were utilized as a nano-AIE probe for cell bioimaging, and many red fluorescent signals were observed in CT26 cells after treatment. These results suggest that Cur@PLGA-NPs provide a novel amorphous AIE formulation with imaging and bioactive capabilities.


Assuntos
Curcumina , Nanopartículas , Curcumina/química , Copolímero de Ácido Poliláctico e Ácido Poliglicólico/química , Luminescência , Nanopartículas/química , Tamanho da Partícula
17.
Front Microbiol ; 14: 1192932, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37266004

RESUMO

Medicinal plants harbor tremendously diverse bacterial endophytes that maintain plant growth and health. In the present study, a total of 124 culturable bacterial endophytes were isolated from healthy Aconitum carmichaelii Debx. plants. These strains were clustered into 10 genera based on full-length 16S rDNA sequences, among which Bacillus and Pseudomonas were the dominant genera. In addition, A. carmichaelii may capture 10 potential new bacterial species based on multi-locus sequence analysis of three housekeeping genes (gyrA, rpoB, and atpD). The majority of these bacterial endophytes exhibited plant growth-promoting ability through diverse actions including the production of either indole acetic acid and siderophore or hydrolytic enzymes (glucanase, cellulose, and protease) and solubilization of phosphate or potassium. A total of 20 strains inhibited hyphal growth of fungal pathogens Sclerotium rolfsii and Fusarium oxysporum in vitro on root slices of A. carmichaelii by the dual-culture method, among which Pseudomonas sp. SWUSTb-19 showed the best antagonistic activity. Field experiment confirmed that Pseudomonas sp. SWUSTb-19 significantly reduced the occurrence of southern blight and promoted plant biomass compared with non-inoculation treatment. The possible mode of actions for Pseudomonas sp. SWUSTb-19 to antagonize against S. rolfsii involved the production of glucanase, siderophore, lipopeptides, and antimicrobial volatile compounds. Altogether, this study revealed that A. carmichaelii harbored diverse plant growth-promoting bacterial endophytes, and Pseudomonas sp. SWUSTb-19 could be served as a potential biocontrol agent against southern blight.

18.
Environ Technol ; : 1-14, 2023 Dec 12.
Artigo em Inglês | MEDLINE | ID: mdl-38084650

RESUMO

The application of organic additives is an efficient strategy to promote the vermicomposting of organic wastes. This study investigated the changes in earthworm growth, nutrients, enzyme activities, microbial composition, and seedling growth during 60 days of vermicomposting of white wine distillers' grains (WWDG) mixed (50:50, w/w) with green waste (GW), green waste compost (GWC), or cow dung (CD). Our data showed that GW, GWC, and CD addition significantly enhanced the survival rate (73.33%-89.17%), growth, and reproduction of earthworms compared to the control treatment. The degradation rate of TOC, the increasing rate of nutriments (total N, total P, total K, available P, available K, humic acid, NH4+, NO3-), and the germination index were significantly higher in the additive treatments than in the control treatment. Dehydrogenase, phosphatases, and urease activities were significantly elevated in the vermicompost amended with additives. The additives remarkably stimulated bacteria, such as Streptomyces, Steroidobacter, Bacillus, Luteibacter, and Rhodanobacter, etc., which were closely related to the biocontrol of phytopathogens and the decomposing recalcitrant substances. Moreover, additives significantly promoted the generation and growth parameters of tomato and lettuce seedlings when compared with the control. In summary, these results indicated that all three additives facilitated the vermicomposting of WWDG and improved the compost quality by enhancing earthworm and enzyme activities as well as altering compost bacterial community, especially when the GWC addition yields the best compost quality and shows strong potential for future application. This study developed a new method for improving WWDG utilization rate and it will promote organic waste recycling in China.

19.
J Control Release ; 356: 205-218, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-36870543

RESUMO

Surgical removal remains the predominant treatment strategy for triple-negative breast cancer (TNBC). However, risks that include high locoregional recurrence and remote metastasis threaten patient survival and quality of life after surgery. In this study, a hydrogel based on poly (ethylene glycol) dimethacrylate and sericin methacryloyl was fabricated by photopolymerization to fill the resection cavity and prevent recurrence. The obtained hydrogel exhibited mechanical properties compatible with breast tissue and facilitated postsurgical wound management by promoting tissue regeneration. The DNA methylation inhibitor decitabine (DEC) and poly (lactic-co-glycolic acid)-encapsulated phytochemical gambogic acid (GA) were loaded into the hydrogel. The as-prepared hydrogel promoted fast release of DEC and sustained release of GA, leading to gasdermin E-mediated tumor cell pyroptosis and activating antitumor immune responses. Inducing postsurgical tumor cell pyroptosis inhibited local tumor recurrence and lung metastasis. While the dual-drug-loaded hydrogel system cured less than half of tumor-bearing mice, the cured mice survived for over half a year. These findings indicate that our hydrogel system is an excellent biocompatible platform for postsurgical TNBC therapy.


Assuntos
Antineoplásicos , Neoplasias de Mama Triplo Negativas , Humanos , Animais , Camundongos , Hidrogéis/química , Neoplasias de Mama Triplo Negativas/tratamento farmacológico , Qualidade de Vida , Linhagem Celular Tumoral
20.
Org Biomol Chem ; 10(5): 925-30, 2012 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-22076205

RESUMO

An efficient modular approach for single-site incorporation of two independent functionalities (amines and alkynes) into aldehyde-containing oligosaccharides concurrently by using a one-pot gold-mediated three-component coupling reaction in aqueous medium under mild conditions has been developed.


Assuntos
Alcinos/química , Aminas/química , Ouro/química , Oligossacarídeos/química , Aldeídos/química
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