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1.
Thorac Cardiovasc Surg ; 72(1): 77-83, 2024 01.
Artigo em Inglês | MEDLINE | ID: mdl-37230479

RESUMO

OBJECTIVE: A retrospective study was conducted to explore the efficacy of bioabsorbable poly-L-lactic acid sternal pins in sternal closure in infants after cardiac surgery. METHODS: A total of 170 infantile patients who underwent cardiac surgery were divided into the steel wire group (group A), the PDS cord group (group B), and the steel wire + sternal pin group (group C). The occurrence of the thoracic deformity was evaluated by vertebral index (VI), frontosagittal index (FSI), and Haller index (HI) values; the stability of the sternum was evaluated by detecting sternal dehiscence and displacement. RESULTS: By comparing the absolute values of the differences in VI, FSI, and HI in the three groups, it was found that the difference values of VI and HI in group C were significantly lower than those in group B (p = 0.028 and 0.005). For the highest deformation index, the deformation rate of infants in group C before discharge and during the 1-year follow-up was lower than that in group A and group B (p = 0.009 and 0.002, respectively). The incidence of sternal displacement in group C was also significantly lower than that in groups A and B (p = 0.009 and 0.009). During the 1-year follow-up, there was no sternal dehiscence, and the sternum healed completely in the three groups. CONCLUSION: The use of "steel wire + sternal pin" for sternal closure in infants after cardiac surgery can reduce the occurrence of sternal deformity, reduce anterior and posterior displacement of the sternum, and improve sternal stability.


Assuntos
Procedimentos Cirúrgicos Cardíacos , Esterno , Lactente , Humanos , Estudos Retrospectivos , Resultado do Tratamento , Esterno/diagnóstico por imagem , Esterno/cirurgia , Procedimentos Cirúrgicos Cardíacos/efeitos adversos , Esternotomia/efeitos adversos , Fios Ortopédicos , Deiscência da Ferida Operatória/etiologia , Deiscência da Ferida Operatória/prevenção & controle , Aço
2.
J Clin Periodontol ; 48(5): 627-637, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-33709419

RESUMO

AIMS: To investigate secular trends in severe periodontitis incidence, prevalence and disability-adjusted life year (DALY) rates in China, India, Japan, South Korea and Thailand from 1990 to 2017. MATERIALS AND METHODS: Data were obtained from the "Global Burden of Disease Study" 2017. The annual percentage change and average annual percentage change were calculated using Joinpoint regression analysis. The independent age, period and cohort effects were estimated by age-period-cohort analysis. RESULTS: From 1990 to 2017, the overall age-standardized incidence, prevalence and DALY rates increased in China, Japan and India, while decreasing in South Korea and Thailand. The highest incidence, prevalence and DALY rates were in India. By APC analysis, the age effect presented increase in 20-59 years in China, Japan and South Korea, 20-54 years in India and 20-64 years in Thailand; the period effect showed progressive increases in five countries, with the most significant increase shown in China; the cohort effect showed monotonic decreases with birth cohort in five countries. CONCLUSIONS: Severe periodontitis poses a serious burden in Asian countries, especially China and India. We suggest raising people's awareness of periodontal health and providing professional interventions in these countries, especially for high-risk groups, such as younger people aged ≤65 years.


Assuntos
Periodontite , Adulto , Idoso , China/epidemiologia , Humanos , Incidência , Japão/epidemiologia , Pessoa de Meia-Idade , Periodontite/epidemiologia , Prevalência , Anos de Vida Ajustados por Qualidade de Vida , República da Coreia , Adulto Jovem
3.
J Exp Bot ; 70(12): 3343-3355, 2019 06 28.
Artigo em Inglês | MEDLINE | ID: mdl-30949671

RESUMO

The whitefly Bemisia tabaci is an important pest of worldwide agriculture. Previous work has shown that B. tabaci actively suppresses host plant defenses, but our knowledge of the specific mechanisms involved remains limited. Here we describe a B. tabaci salivary protein, the ferritin BtFer1, and its role in facilitating exploitation of host plants. We show that BtFer1 exhibits Fe2+ binding ability and ferroxidase activity, and that secretion of BtFer1 during B. tabaci feeding suppresses H2O2-generated oxidative signals in tomato (Solanum lycopersicum). Silencing BtFer1 enhanced the induction of the jasmonic acid (JA)-mediated defense signaling pathway in response to whitefly feeding, and led to increased callose deposition and the production of proteinase inhibitors that prevent whiteflies from continuously ingesting and digesting phloem sap. Consistent with these effects, silencing BtFer1 reduced whitefly survival on tomato but not on artificial diet. Using a JA-deficient spr2 mutant plant further showed that suppression of JA defenses by BtFer1 is sufficient to increase B. tabaci survival. Taken together, these results demonstrate that BtFer1 acts as an effector protein that mediates whitefly-tomato interactions. These findings represent an important step forward in understanding the molecular mechanisms by which whiteflies and other insect herbivores suppress host plant defenses.


Assuntos
Ferritinas/genética , Hemípteros/genética , Herbivoria , Proteínas de Insetos/genética , Transdução de Sinais , Solanum lycopersicum/fisiologia , Animais , Ciclopentanos/metabolismo , Ferritinas/metabolismo , Cadeia Alimentar , Hemípteros/metabolismo , Proteínas de Insetos/metabolismo , Oxilipinas/metabolismo , Saliva/química
4.
Water Sci Technol ; 77(5-6): 1683-1688, 2018 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-29595170

RESUMO

Aquatic plants are widely used for treating wastewater treatment plant secondary effluent. During this process, some residual activated sludge in the secondary effluent is intercepted and attaches to the plant roots. However, the effect of the attached activated sludge on nutrient removal in secondary effluent has up to now been unknown. Aiming at this problem, this investigation was conducted to compare the nutrient removal rates in secondary effluent by washed Pistia stratiotes (washed batch) and Pistia stratiotes with activated sludge attached to the roots (study batch). Extracellular polymeric substances (EPS) from the activated sludge attached to the roots were extracted and characterized by three-dimensional excitation emission matrix (3D-EEM) fluorescence spectroscopy. The results showed that the nutrient removal rates in the study batch were better than that in the washed batch. The 3D-EEM results showed that the protein content of EPS increased during the experiment, indicating the growth of microorganisms in the attached activated sludge. Our work demonstrated the enhanced effect of activated sludge attached to the roots of Pistia stratiotes on the removal of pollutants in secondary effluent, which is useful to guide the practical engineering of secondary effluent treatment.


Assuntos
Araceae/metabolismo , Raízes de Plantas/metabolismo , Esgotos/química , Poluentes Químicos da Água/metabolismo , Polímeros/metabolismo , Eliminação de Resíduos Líquidos/métodos , Águas Residuárias , Poluentes Químicos da Água/química , Purificação da Água
5.
Biochem Biophys Res Commun ; 482(4): 835-842, 2017 Jan 22.
Artigo em Inglês | MEDLINE | ID: mdl-27889607

RESUMO

Sjögren's syndrome (SjS) is a systemic autoimmune disease resulting in a severe dry mouth and dry eyes. Currently, care for patients with SjS is palliative, as no established therapeutics target the disease directly, and its pathogenetic mechanisms are uncertain. Leptin activates B cells to induce the secretion of proinflammatory and anti-inflammatory cytokines and is elevated in several autoimmune diseases. In this study, we found the expression of leptin and its receptor OB-R in mouse models of SjS are elevated both locally and systemically during SjS progression. Recombinant serotype 2 adeno-associated viral (rAAV2) vectors expressing either OB-R shRNA (rAAV2-shOB-R) or none (rAAV2-null) were injected into 4 or 16 week-old BALB/c NOD/LtJ (NOD) mice and resulted in a modest reduction in glandular inflammation in the SjS model. In conclusion, Leptin/OB-R signaling may be pathogenically involved in SjS and may serve as a new marker and a potential therapeutic target.


Assuntos
Leptina/genética , Receptores para Leptina/genética , Síndrome de Sjogren/genética , Regulação para Cima , Animais , Modelos Animais de Doenças , Feminino , Humanos , Inflamação/genética , Inflamação/patologia , Leptina/análise , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos NOD , Receptores para Leptina/análise , Transdução de Sinais , Síndrome de Sjogren/patologia
6.
Biosens Bioelectron ; 254: 116201, 2024 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-38507928

RESUMO

Developing highly sensitive and selective methods that incorporate specific recognition elements is crucial for detecting small molecules because of the limited availability of small molecule antibodies and the challenges in obtaining sensitive signals. In this study, a generalizable photoelectrochemical-colorimetric dual-mode sensing platform was constructed based on the synergistic effects of a molecularly imprinted polymer (MIP)-aptamer sandwich structure and nanoenzymes. The MIP functionalized peroxidase-like Fe3O4 (Fe3O4@MIPs) and alkaline phosphatase mimic Zr-MOF labeled aptamer (Zr-mof@Apt) were used as the recognition elements. By selectively accumulating dibutyl phthalate (DBP), a small molecule target model, on Fe3O4@MIPs, the formation of Zr-MOF@Apt-DBP- Fe3O4@MIPs sandwich structure was triggered. Fe3O4@MIPs oxidized TMB to form blue-colored oxTMB. However, upon selective accumulation of DBP, the catalytic activity of Fe3O4@MIPs was inhibited, resulting in a lighter color that was detectable by the colorimetric method. Additionally, Zr-mof@Apt effectively catalyzed the hydrolysis of L-Ascorbic acid 2-phosphate sesquimagnesium salt hydrate (AAPS), generating ascorbic acid (AA) that could neutralize the photogenerated holes to decrease the photocurrent signals for PEC sensing and reduce oxTMB for colorimetric testing. The dual-mode platform showed strong linearity for different concentrations of DBP from 1.0 pM to 10 µM (PEC) and 0.1 nM to 0.5 µM (colorimetry). The detection limits were 0.263 nM (PEC) and 30.1 nM (colorimetry) (S/N = 3), respectively. The integration of dual-signal measurement mode and sandwich recognition strategy provided a sensitive and accurate platform for the detection of small molecules.


Assuntos
Técnicas Biossensoriais , Polímeros Molecularmente Impressos , Colorimetria/métodos , Peroxidase/química , Peroxidases
7.
Plant Commun ; 5(1): 100681, 2024 Jan 08.
Artigo em Inglês | MEDLINE | ID: mdl-37660253

RESUMO

Bananas (Musa spp.) are monocotyledonous plants with high genetic diversity in the Musaceae family that are cultivated mainly in tropical and subtropical countries. The fruits are a popular food, and the plants themselves have diverse uses. Four genetic groups (genomes) are thought to have contributed to current banana cultivars: Musa acuminata (A genome), Musa balbisiana (B genome), Musa schizocarpa (S genome), and species of the Australimusa section (T genome). However, the T genome has not been effectively explored. Here, we present the high-quality TT genomes of two representative accessions, Abaca (Musa textilis), with high-quality natural fiber, and Utafun (Musa troglodytarum, Fe'i group), with abundant ß-carotene. Both the Abaca and Utafun assemblies comprise 10 pseudochromosomes, and their total genome sizes are 613 Mb and 619 Mb, respectively. Comparative genome analysis revealed that the larger size of the T genome is likely attributable to rapid expansion and slow removal of transposons. Compared with those of Musa AA or BB accessions or sisal (Agava sisalana), Abaca fibers exhibit superior mechanical properties, mainly because of their thicker cell walls with a higher content of cellulose, lignin, and hemicellulose. Expression of MusaCesA cellulose synthesis genes peaks earlier in Abaca than in AA or BB accessions during plant development, potentially leading to earlier cellulose accumulation during secondary cell wall formation. The Abaca-specific expressed gene MusaMYB26, which is directly regulated by MusaMYB61, may be an important regulator that promotes precocious expression of secondary cell wall MusaCesAs. Furthermore, MusaWRKY2 and MusaNAC68, which appear to be involved in regulating expression of MusaLAC and MusaCAD, may at least partially explain the high accumulation of lignin in Abaca. This work contributes to a better understanding of banana domestication and the diverse genetic resources in the Musaceae family, thus providing resources for Musa genetic improvement.


Assuntos
Musa , Musa/genética , Genoma de Planta , Lignina
8.
Mil Med Res ; 11(1): 30, 2024 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-38764065

RESUMO

BACKGROUND: Benign prostatic hyperplasia (BPH) is the most common disease in elderly men. There is increasing evidence that periodontitis increases the risk of BPH, but the specific mechanism remains unclear. This study aimed to explore the role and mechanism of the key periodontal pathogen Porphyromonas gingivalis (P. gingivalis) in the development of BPH. METHODS: The subgingival plaque (Sp) and prostatic fluid (Pf) of patients with BPH concurrent periodontitis were extracted and cultured for 16S rDNA sequencing. Ligature-induced periodontitis, testosterone-induced BPH and the composite models in rats were established. The P. gingivalis and its toxic factor P. gingivalis lipopolysaccharide (P.g-LPS) were injected into the ventral lobe of prostate in rats to simulate its colonization of prostate. P.g-LPS was used to construct the prostate cell infection model for mechanism exploration. RESULTS: P. gingivalis, Streptococcus oralis, Capnocytophaga ochracea and other oral pathogens were simultaneously detected in the Pf and Sp of patients with BPH concurrent periodontitis, and the average relative abundance of P. gingivalis was found to be the highest. P. gingivalis was detected in both Pf and Sp in 62.5% of patients. Simultaneous periodontitis and BPH synergistically aggravated prostate histological changes. P. gingivalis and P.g-LPS infection could induce obvious hyperplasia of the prostate epithelium and stroma (epithelial thickness was 2.97- and 3.08-fold that of control group, respectively), and increase of collagen fibrosis (3.81- and 5.02-fold that of control group, respectively). P. gingivalis infection promoted prostate cell proliferation, inhibited apoptosis, and upregulated the expression of inflammatory cytokines interleukin-6 (IL-6; 4.47-fold), interleukin-6 receptor-α (IL-6Rα; 5.74-fold) and glycoprotein 130 (gp130; 4.47-fold) in prostatic tissue. P.g-LPS could significantly inhibit cell apoptosis, promote mitosis and proliferation of cells. P.g-LPS activates the Akt pathway through IL-6/IL-6Rα/gp130 complex, which destroys the imbalance between proliferation and apoptosis of prostate cells, induces BPH. CONCLUSION: P. gingivalis was abundant in the Pf of patients with BPH concurrent periodontitis. P. gingivalis infection can promote BPH, which may affect the progression of BPH via inflammation and the Akt signaling pathway.


Assuntos
Interleucina-6 , Porphyromonas gingivalis , Hiperplasia Prostática , Receptores de Interleucina-6 , Masculino , Hiperplasia Prostática/complicações , Porphyromonas gingivalis/patogenicidade , Ratos , Humanos , Animais , Interleucina-6/análise , Interleucina-6/metabolismo , Próstata , Periodontite/complicações , Periodontite/microbiologia , Idoso , Pessoa de Meia-Idade , Ratos Sprague-Dawley , Modelos Animais de Doenças , Transdução de Sinais/fisiologia
9.
Biomol Biomed ; 23(1): 126-136, 2023 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-35880401

RESUMO

The aim of this in vitro study was to evaluate the effect of three final irrigants, namely QMix, MTAD and EDTA, combined with three irrigation techniques, namely conventional needle irrigation (CNI), passive ultrasonic irrigation (PUI) and photon-induced photoacoustic streaming (PIPS), on smear layer removal, dentin mineral content and microhardness in oval-shaped canals.    130 decoronated premolars with single, oval root canals were equally divided into1 blank control group and 12 treatment groups (n=10) according to the final irrigation protocols. Roots in treatment groups were instrumented with ProTaper Gold to size F4 and subjected to final irrigation. Smear layer removal was assessed by using a four-level scoring system under an environmental scanning electron microscope. Energy dispersive X-ray spectroscopy was performed to measure the dentin mineral content. Dentin microhardness was measured by Knoop microhardness testing. Statistical analysis of the data was performed by using Kruskal-Wallis test, followed by Dunn's post hoc test with Bonferroni correction. PUI- and PIPS-activated QMix and EDTA removed smear layer more effectively than MTAD groups (p<0.05). Regarding the dentin mineral content and microhardness, QMix groups yielded the least calcium (Ca), phosphorus (P)  and Ca/P ratio, followed by EDTA groups and MTAD groups (p<0.05). QMix groups produced significantly lower dentin microhardness values and higher hardness reduction percentages than MTAD groups (p<0.05).  Within the limitations of the present study, it was concluded that QMix and EDTA were superior to MTAD in smear layer removal, especially when activated by PUI and PIPS, but these agents produced more pronounced effect on dentin mineral content and microhardness than MTAD.


Assuntos
Camada de Esfregaço , Humanos , Ácido Edético/farmacologia , Cavidade Pulpar , Microscopia Eletrônica de Varredura , Dentina , Minerais/farmacologia , Cálcio da Dieta/farmacologia , Irrigantes do Canal Radicular/farmacologia
10.
Int Immunopharmacol ; 109: 108797, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35487085

RESUMO

Periodontitis (PD), also known as gum disease, is a condition causing inflammatory bone resorption and tooth loss. Regulatory T cells (Tregs) and regulatory B cells (Bregs) are vital in controlling the immune response and hence play a role in infections and peripheral tolerance adjustment. These cells have immunosuppressive and tissue-repairing capabilities that are important for periodontal health; however, in inflammatory circumstances, Tregs may become unstable and dysfunctional, accelerating tissue deterioration. In recent years, Regulatory cell-mediated immunotherapy has been shown to be effective in many inflammatory diseases. Considering the roles of Tregs and Bregs in shaping immune responses, this study aimed to review the published articles in this field to provide a comprehensive view of the existing knowledge about the role of regulatory T and B cells, as well as their therapeutic applications in PD.


Assuntos
Linfócitos B Reguladores , Periodontite , Humanos , Imunossupressores , Imunoterapia , Periodontite/terapia , Linfócitos T Reguladores
11.
ChemSusChem ; 15(23): e202201455, 2022 Dec 07.
Artigo em Inglês | MEDLINE | ID: mdl-36163546

RESUMO

Immobilizing cobalt phthalocyanine (CoPc) onto the electrode surface is a significant approach to performing efficient electrochemical CO2 reduction reaction (ECO2 RR). Herein, sulfylphenoxy decorated CoPc cross-linked polypyrrole is prepared by in situ polymerization on the surface of carbon cloth. The synthesized N-rich catalyst exhibits above 95 % Faradaic efficiency toward CO (FECO ) at -0.9 V versus reversible hydrogen electrode (RHE) at least for 10 h in aqueous solution and even enables direct electrolysis at low CO2 concentrations, being potential for coupling ECO2 RR with CO2 capture. This facile in situ polymerization strategy would pave the way for developing efficient and practical electrocatalysis for ECO2 RR.


Assuntos
Polímeros , Pirróis , Dióxido de Carbono , Indóis
12.
J Dent Sci ; 17(4): 1520-1527, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-36299306

RESUMO

Background/purpose: Glide path management (GPM) is a consequential clinical step that serves to influence predictably successful root canal therapy. However, the effect of GPM on the shaping ability of single-file system remains controversial. This study compared the performance of rotary single-file One Curve (OC) and reciprocating single-file Reciproc Blue (RCB) in combination with/without different glide path techniques: no glide path preparation (NG), PathFile (PF), ProGlider (PG) and WaveOne Gold Glider (WOGG), respectively. Materials and methods: 80 simulated curved canals (n = 10 canals/per group) were instrumented to an apical size of 0.25 mm using OC and RCB in combination with/without different glide path techniques, respectively. The amount of resin removal, canal transportation, and the degree of canal straightening were measured in Photoshop CS6 software. Statistical analysis of the data was performed by using Kruskal-Wallis test, followed by Dunn's post hoc test with Bonferroni correction (α = 0.05). Results: Post-glide path analysis found that WOGG and PG produced less canal transportation and curvature straightening than PF (P < 0.05). Post-shaping analysis showed that OC groups removed significantly less resin than RCB groups (P < 0.05). The PG and WOGG subgroups in both OC groups and RCB groups produced less transportation and curvature straightening than NG and PF subgroups (P < 0.05). OC + PG subgroup and OC + WOGG subgroup yielded the least canal transportation and curvature straightening (P < 0.05). Conclusion: PG and WOGG can improve the shaping ability of OC and RCB instrument. OC, especially when combined with PG and WOGG, has a less aggressive dentin cutting and more centered preparation than the RCB instrument.

13.
Theranostics ; 10(6): 2463-2478, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32194813

RESUMO

There is an urgent and unmet need to develop effective therapies for triple negative breast cancers (TNBCs) which are much more aggressive and have poor prognosis due to lack of receptor targets for Her2-targeted and endocrine therapy. In this study we systematically evaluated the effect of Vorinostat (SAHA, a pan-HDAC inhibitor) in reactivating the expression of functional estrogen receptor α (ERα) and synergizing with tamoxifen (TAM, a selective estrogen-receptor modulator) in antitumor activity. In addition, a SAHA prodrug-based dual functional nanocarrier was developed for codelivery of SAHA and TAM for effective combination therapy. Methods: A SAHA-containing polymeric nanocarrier, POEG-co-PVDSAHA was developed via reversible addition-fragmentation transfer (RAFT) polymerization with SAHA incorporated into the polymer through a redox-responsive disulfide linkage. The effect of both free SAHA and POEG-co-PVDSAHA on reactivating the expression of functional ERα was investigated in several human and murine TNBC cell lines via examining the mRNA and protein expression of ERα target genes. The cytotoxicity of free SAHA and TAM combination and TAM-loaded POEG-co-PVDSAHA micelles was examined via MTT assay. The in vivo antitumor activity of TAM-loaded POEG-co-PVDSAHA was investigated in a murine breast cancer model (4T1.2). Results: Both free SAHA and POEG-co-PVDSAHA were effective in inducing the reexpression of functional estrogen receptor α (ERα), which may have helped to sensitize TNBCs to TAM. More importantly, POEG-co-PVDSAHA self-assembled to form small-sized micellar carrier that is effective in formulating and codelivery of TAM. TAM-loaded POEG-co-PVDSAHA micelles exhibited enhanced and synergistic cytotoxicity against TNBC cell lines compared with free SAHA, free TAM and TAM loaded into a pharmacologically inert control carrier (POEG-co-PVMA). In addition, codelivery of TAM via POEG-co-PVDSAHA micelles led to significantly improved antitumor efficacy in 4T1.2 tumor model compared with other groups such as combination of free SAHA and TAM and TAM-loaded POEG-co-PVMA micelles. Conclusion: Our prodrug-based co-delivery system may provide an effective and simple strategy to re-sensitize TNBCs to TAM-based hormone therapy.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/administração & dosagem , Portadores de Fármacos/administração & dosagem , Pró-Fármacos/administração & dosagem , Tamoxifeno/administração & dosagem , Neoplasias de Mama Triplo Negativas/tratamento farmacológico , Vorinostat/administração & dosagem , Animais , Protocolos de Quimioterapia Combinada Antineoplásica/farmacologia , Linhagem Celular Tumoral , Portadores de Fármacos/farmacologia , Combinação de Medicamentos , Sinergismo Farmacológico , Receptor alfa de Estrogênio/metabolismo , Feminino , Glutationa/metabolismo , Inibidores de Histona Desacetilases/administração & dosagem , Inibidores de Histona Desacetilases/farmacologia , Humanos , Camundongos , Camundongos Endogâmicos BALB C , Micelas , Nanopartículas/administração & dosagem , Oxirredução/efeitos dos fármacos , Polímeros/química , Polímeros/farmacologia , Pró-Fármacos/farmacologia , Tamoxifeno/farmacologia , Neoplasias de Mama Triplo Negativas/patologia , Vorinostat/farmacologia
14.
J Hazard Mater ; 384: 121311, 2020 02 15.
Artigo em Inglês | MEDLINE | ID: mdl-31585278

RESUMO

Metabolic uncouplers are widely used for reducing excess sludge in biological wastewater treatment systems. However, the formation of microbial products, such as extracellular polymeric substances, polyhydroxyalkanoate and soluble microbial products by activated sludge in the presence of metabolic uncouplers remains unrevealed. In this study, the impacts of a metabolic uncoupler o-chlorophenol (oCP) on the reduction of activated sludge yield and formation of microbial products in laboratory-scale sequencing batch reactors (SBRs) were evaluated for a long-term operation. The results show the average reduction of sludge yield in the four reactors was 17.40%, 25.80%, 33.02% and 39.50%, respectively, when dosing 5, 10, 15, and 20 mg/L oCP. The oCP addition slightly reduced the pollutant removal efficiency and decreased the formation of soluble microbial products in the SBRs, but stimulated the productions of extracellular polymeric substances and polyhydroxyalkanoate in activated sludge. Furthermore, the significant reduction of electronic transport system activity occurred after the oCP addition. Microbial community analysis of the activated sludge indicates dosing oCP resulted in a decrease of sludge richness and diversity in the SBRs. Hopefully, this study would provide useful information for reducing sludge yield in biological wastewater treatment systems and behaviors of activated sludge in the presence of uncouplers.


Assuntos
Clorofenóis/farmacologia , Esgotos/microbiologia , Desacopladores/farmacologia , Águas Residuárias/microbiologia , Análise da Demanda Biológica de Oxigênio , Reatores Biológicos , DNA Bacteriano/biossíntese , DNA Bacteriano/genética , Polímeros/química , Eliminação de Resíduos Líquidos , Poluentes Químicos da Água/química
15.
Water Res ; 43(5): 1350-8, 2009 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-19215955

RESUMO

In this work the extracellular polymeric substances (EPS) produced by mixed microbial community in activated sludge are characterized using gel-permeating chromatography (GPC), 3-dimensional excitation-emission matrix (EEM) fluorescence spectroscopy measurement and mathematical modeling. Chromatograms of extracted EPS exhibit seven peaks, among which proteins have four peaks and polysaccharides have three peaks. Evolution of the chromatogram area indicates that the quantity of produced EPS increases significantly in the substrate utilization process. With the parallel factor analysis (PARAFAC) approach, two components of the polymer matrix are identified by the EEM analysis, one as EPS proteins at Ex/Em 280/340 nm and one matrix associated as fulvic-acid-like substances at 320/400 nm. The proteins and fulvic-acid-like substances in the EPS increase in the substrate utilization phase, but decrease in the endogenous phase. To have a better insight into EPS production, the kinetic modeling of EPS is performed with regard to their molecular weight distribution and chemical natures identified by GPC and EEM. In this way, the dynamics of these important microbial products are better understood.


Assuntos
Bactérias/metabolismo , Biopolímeros/metabolismo , Cromatografia em Gel , Espaço Extracelular/metabolismo , Modelos Biológicos , Esgotos/microbiologia , Benzopiranos/metabolismo , Calibragem , Cinética , Peso Molecular , Espectrometria de Fluorescência , Fatores de Tempo
16.
Biomaterials ; 210: 25-40, 2019 07.
Artigo em Inglês | MEDLINE | ID: mdl-31054369

RESUMO

Metastasis is the major cause for breast cancer related mortality. The combination of miRNA-based therapy and chemotherapy represents a promising approach against breast cancer lung metastasis. The goal of this study is to develop an improved therapy that co-delivers a novel bioengineered miRNA prodrug (tRNA-mir-34a) and doxorubicin (DOX) via a multifunctional nanomicellar carrier that is based on a conjugate of amphiphilic copolymer POEG-VBC backbone with creatine, a naturally occurring cationic molecule. Co-delivery of DOX leads to more effective processing of tRNA-mir-34a into mature miR-34a and down-regulation of target genes. DOX + tRNA-mir-34a/POEG-PCre exhibits potent synergistic anti-tumor and anti-metastasis activity in vitro and in vivo. Interestingly, the enhanced immune response contributes to the overall antitumor efficacy. POEG-PCre may represent a safe and effective delivery system for an optimal chemo-gene combination therapy.


Assuntos
Antineoplásicos/uso terapêutico , Bioengenharia , Neoplasias da Mama/patologia , Creatina/química , Sistemas de Liberação de Medicamentos , Neoplasias Pulmonares/secundário , MicroRNAs/administração & dosagem , Polímeros/química , Animais , Antineoplásicos/administração & dosagem , Antineoplásicos/farmacologia , Linhagem Celular Tumoral , Regulação para Baixo/efeitos dos fármacos , Endocitose/efeitos dos fármacos , Feminino , Humanos , Neoplasias Pulmonares/tratamento farmacológico , Camundongos Endogâmicos BALB C , Micelas , Nanopartículas/química , Polímeros/síntese química , Distribuição Tecidual/efeitos dos fármacos
17.
J Control Release ; 303: 77-90, 2019 06 10.
Artigo em Inglês | MEDLINE | ID: mdl-31004666

RESUMO

Activation of hepatic stellate cells (HSCs) contributes to the development of liver fibrosis. Because of a relatively small population of HSCs in the liver and the lack of specific membrane targeting proteins, HSC-targeted therapy remains a major clinical challenge. Here we first showed that a hallmark of activated HSC (aHSC) is their increased expression of integrin αvß3. Thus we established sterically stable liposomes that contain the cyclic peptides (cRGDyK) with a high affinity to αvß3 to achieve aHSC-specific delivery. Our results showed that the cRGDyK-guided liposomes were preferentially internalized by activated HSCs in vitro and in vivo, and the internalization was abolished by excess free cRGDyK or knockdown of αvß3. In contrast, quiescent HSCs, hepatocytes, Kupffer cells, sinusoidal endothelial cells, or biliary cells showed minimal uptake of the cRGDyK-guided liposomes. When loaded with the hedgehog inhibitor vismodegib, the cRGDyK-guided liposomes inhibited hedgehog pathway signaling specifically in activated HSCs. Moreover, treatment of mice with vismodegib-loaded cRGDyK-liposomes markedly inhibited the fibrogenic phenotype in bile duct ligation- or thioacetamide-treated mice. We conclude that the cRGDyK-guided liposomes can specifically target the activated HSCs, but not quiescent HSCs. This nanoparticle system showed great promise to deliver therapeutic agents to aHSC to treat liver fibrosis.


Assuntos
Células Estreladas do Fígado/efeitos dos fármacos , Integrina alfaVbeta3/metabolismo , Cirrose Hepática/tratamento farmacológico , Nanopartículas/administração & dosagem , Peptídeos Cíclicos/administração & dosagem , Animais , Células Cultivadas , Células Endoteliais/metabolismo , Células Estreladas do Fígado/metabolismo , Hepatócitos/metabolismo , Células de Kupffer/metabolismo , Lipossomos , Camundongos
18.
Zhonghua Yu Fang Yi Xue Za Zhi ; 41 Suppl: 119-22, 2007 Jun.
Artigo em Zh | MEDLINE | ID: mdl-17767875

RESUMO

OBJECTIVE: To discuss the relations of dental fluorosis and the social economic status in fluorosis-stricken villages where drying the corn by burning coal was prevail. METHODS: A total of 6 fluorosis-endemic villages and one non-endemic village were involved in the study. The general fluorine intake and the concentrations of fluorine in corn, in the pupils' were tested. Dental fluorosis among the pupils was also examen. A individual interview or household questionnaire survey was conducted to probe the economic condition and staple food structure in 600 adults. RESULTS: The fluorosis prevalence was lower in the villages of transportation convenience, higher income, less coal-dried corn intake. There was a declining trend of dental fluorosis in the corresponding age groups (r: 0.912, 0.916; P < 0.05); There was no significant changes in age-specified dental fluorosis in the low income villages. The correlation (r) of corn fluorine concentration and student's age-specified dental fluorosis prevalence and disparity was 0.755 - 0.980 (P < 0.05) and 0.302 - 0.811; The urine fluorine concentrations were 0.811 and 0.915 (P < 0.05). It was assumed that there was a negative correlation between family cash income and the dental fluorosis. CONCLUSIONS: The corn fluorine concentration is closely related to age-specified dental fluorosis. With the economic improvement, taking less coal-burned corn is the one of major factors in reducing the of dental fluorosis in these areas.


Assuntos
Comportamento Alimentar , Flúor/análise , Fluorose Dentária/economia , Fluorose Dentária/epidemiologia , China , Carvão Mineral , Análise Fatorial , Flúor/urina , Humanos , População Rural , Zea mays
19.
Nat Commun ; 7: 13443, 2016 11 07.
Artigo em Inglês | MEDLINE | ID: mdl-27819653

RESUMO

Immunochemotherapy combines a chemotherapeutic agent with an immune-modulating agent and represents an attractive approach to improve cancer therapy. However, the success of immunochemotherapy is hampered by the lack of a strategy to effectively co-deliver the two therapeutics to the tumours. Here we report the development of a dual-functional, immunostimulatory nanomicellar carrier that is based on a prodrug conjugate of PEG with NLG919, an indoleamine 2,3-dioxygenase (IDO) inhibitor currently used for reversing tumour immune suppression. An Fmoc group, an effective drug-interactive motif, is also introduced into the carrier to improve the drug loading capacity and formulation stability. We show that PEG2k-Fmoc-NLG alone is effective in enhancing T-cell immune responses and exhibits significant antitumour activity in vivo. More importantly, systemic delivery of paclitaxel (PTX) using the PEG2k-Fmoc-NLG nanocarrier leads to a significantly improved antitumour response in both breast cancer and melanoma mouse models.


Assuntos
Antineoplásicos/imunologia , Neoplasias da Mama/terapia , Imidazóis/imunologia , Imunoterapia/métodos , Isoindóis/imunologia , Animais , Antineoplásicos/química , Antineoplásicos/farmacologia , Neoplasias da Mama/imunologia , Linhagem Celular Tumoral , Portadores de Fármacos/química , Portadores de Fármacos/farmacologia , Feminino , Humanos , Imidazóis/química , Imidazóis/farmacologia , Indolamina-Pirrol 2,3,-Dioxigenase/antagonistas & inibidores , Isoindóis/química , Isoindóis/farmacologia , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Micelas , Nanoconjugados/administração & dosagem , Nanoconjugados/química , Paclitaxel , Polietilenoglicóis/administração & dosagem , Polietilenoglicóis/química , Pró-Fármacos/química , Pró-Fármacos/farmacologia , Distribuição Tecidual , Resultado do Tratamento , Ensaios Antitumorais Modelo de Xenoenxerto
20.
Mater Sci Eng C Mater Biol Appl ; 46: 366-73, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25491999

RESUMO

Both biodegradable aliphatic neat poly(butylene succinate) (PBS) and poly(butylene succinate-co-neopentyl glycol succinate) (P(BS-co-NPGS)) copolyesters with different 1,4-butanediol/neopentyl glycol ratios were synthesized through a two-step process of transesterification and polycondensation using stannous chloride and 4-Methylbenzenesulfonic acid as the co-catalysts. The structure, non-isothermal crystallization behavior, crystalline morphology and crystal structure of neat PBS and P(BS-co-NPGS) copolyesters were characterized by (1)H NMR, differential scanning calorimetry (DSC), polarized optical microscope (POM) and wide angle X-ray diffraction (WAXD), respectively. The Avrami equation modified by Jeziorny and Mo's method was employed to describe the non-isothermal crystallization kinetics of the neat PBS and its copolyesters. The modified Avrami equation could adequately describe the primary stage of non-isothermal crystallization kinetics of the neat PBS and its copolyesters. Mo's method provided a fairly satisfactory description of the non-isothermal crystallization of neat PBS and its copolyesters. Interestingly, the values of 1/t1/2, Zc and F(T) obtained by the modified Avrami equation and Mo's method analysis indicated that the crystallization rate increased first and then decreased with an increase of NPGS content compared that of neat PBS, whereas the crystallization mechanism almost kept unchanged. The results of tensile testing showed that the ductility of PBS was largely improved by incorporating NPGS units. The elongation at break increased remarkably with increasing NPGS content. In particular, the sample with 20% NPGS content showed around 548% elongation at break.


Assuntos
Materiais Biocompatíveis , Poliésteres/química , Cristalização , Cinética , Espectroscopia de Prótons por Ressonância Magnética
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