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1.
Environ Res ; 251(Pt 2): 118673, 2024 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-38493845

RESUMO

Both microplastics (MPs) and heavy metals are common soil pollutants and can interact to generate combined toxicity to soil ecosystems, but their impact on soil microbial communities (e.g., archaea and viruses) remains poorly studied. Here, metagenomic analysis was used to explore the response of soil microbiome in an agricultural soil exposed to MPs [i.e., polyethylene (PE), polystyrene (PS), and polylactic acid (PLA)] and/or Cd. Results showed that MPs had more profound effects on microbial community composition, diversity, and gene abundances when compared to Cd or their combination. Metagenomic analysis indicated that the gene taxonomic diversity and functional diversity of microbial communities varied with MPs type and dose. MPs affected the relative abundance of major microbial phyla and genera, while their coexistence with Cd influenced dominant fungi and viruses. Nitrogen-transforming and pathogenic genera, which were more sensitive to MPs variations, could serve as the indicative taxa for MPs contamination. High-dose PLA treatments (10%, w/w) not only elevated nitrogen metabolism and pathogenic genes, but also enriched copiotrophic microbes from the Proteobacteria phylum. Overall, MPs and Cd showed minimal interactions on soil microbial communities. This study highlights the microbial shifts due to co-occurring MPs and Cd, providing evidence for understanding their environmental risks.


Assuntos
Cádmio , Metagenômica , Microplásticos , Microbiologia do Solo , Poluentes do Solo , Cádmio/toxicidade , Cádmio/análise , Poluentes do Solo/toxicidade , Poluentes do Solo/análise , Microplásticos/toxicidade , Agricultura , Microbiota/efeitos dos fármacos , Solo/química , Bactérias/genética , Bactérias/classificação , Bactérias/efeitos dos fármacos
2.
J Environ Manage ; 351: 119807, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38100864

RESUMO

Accurate prediction of the dissolved oxygen level (DOL) is important for enhancing environmental conditions and facilitating water resource management. However, the irregularity and volatility inherent in DOL pose significant challenges to achieving precise forecasts. A single model usually suffers from low prediction accuracy, narrow application range, and difficult data acquisition. This study proposes a new weighted model that avoids these problems, which could increase the prediction accuracy of the DOL. The weighting constructs of the proposed model (PWM) included eight neural networks and one statistical method and utilized Young's double-slit experimental optimizer as an intelligent weighting tool. To evaluate the effectiveness of PWM, simulations were conducted using real-world data acquired from the Tualatin River Basin in Oregon, United States. Empirical findings unequivocally demonstrated that PWM outperforms both the statistical model and the individual machine learning models, and has the lowest mean absolute percentage error among all the weighted models. Based on two real datasets, the PWM can averagely obtain the mean absolute percentage errors of 1.0216%, 1.4630%, and 1.7087% for one-, two-, and three-step predictions, respectively. This study shows that the PWM can effectively integrate the distinctive merits of deep learning methods, neural networks, and statistical models, thereby increasing forecasting accuracy and providing indispensable technical support for the sustainable development of regional water environments.


Assuntos
Modelos Teóricos , Oxigênio , Modelos Estatísticos , Redes Neurais de Computação , Rios
3.
BMC Oral Health ; 24(1): 378, 2024 Mar 22.
Artigo em Inglês | MEDLINE | ID: mdl-38519948

RESUMO

BACKGROUND: Ameloblastoma (AM) is the most common benign odontogenic tumor, which is more often detected in the mandible than maxilla, especially the mandibular body and mandibular angle. Pediatric AM is a rare disease, especially in patients aged 10 and younger. Compared with the mainstream osteotomy and reconstructive surgery for adult ameloblastoma, there is more room for discussion in the treatment of pediatric ameloblastoma. The postoperative functional and psychological influence can not be ignored. Especially for children in the period of growth and development, an osteotomy is often challenging to be accepted by their parents. We report two patients with ameloblastoma under 10 years old who are treated with curettage and fenestration, which is a beneficial method for children with ameloblastoma. CASE PRESENTATION: We present two cases of classic ameloblastoma in children. We describe in detail the patients' characteristics, treatment processes, and follow-up result. The bone formation and reconstruction in the lesion area after fenestration decompression and curettage are recorded at every clinic review. The surgical details and principles of curettage and decompression are also described and discussed. The two patients have good bone shape recovery and no recurrence. CONCLUSIONS: Children are in the growth and development period and possess an extremely strong ability of bone formation and reconstruction. Based on the principles of minimally invasive and functional preservation, we believe that curettage combined with decompression can be the first choice for treating AM in children, especially for mandibular lesions.


Assuntos
Ameloblastoma , Neoplasias Mandibulares , Criança , Humanos , Ameloblastoma/cirurgia , Curetagem/métodos , Descompressão , Mandíbula/cirurgia , Neoplasias Mandibulares/cirurgia
4.
Nucleic Acids Res ; 48(17): 9986-9994, 2020 09 25.
Artigo em Inglês | MEDLINE | ID: mdl-32853337

RESUMO

Telomeric DNA, whose length homeostasis is closely correlated with immortality of cancer cells, is regarded as a molecular clock for cellular lifespan. Regarding the capacity in forming G-quadruplex, G-rich 3'-overhang (G-overhang) has been considered as an attractive anticancer target. However, it is still challenging to precisely target telomeric G-overhang with current ligands because of the polymorphism of G-quadruplexes in cells. Herein, we construct a telomeric G-overhang-specific near-infrared-traceable DNA nano-hydrolase, which is composed of four parts: (i) dexamethasone for targeting cell nuclei; (ii) complementary DNA for hybridizing with G-overhang; (iii) multinuclear Ce(IV) complexes for hydrolyzing G-overhang; and (iv) upconversion nanoparticles for real-time tracking. The multivalent targeted DNA nano-hydrolase can be traced to precisely digest telomeric G-overhang, which contributes to telomeric DNA shortening and thereby causes cell aging and apoptosis. The anticancer treatment is further proved by in vivo studies. In this way, this design provides a telomeric G-overhang-specific eradication strategy based on a non-G-quadruplex targeting manner.


Assuntos
Antineoplásicos/farmacologia , Nanopartículas/química , Neoplasias Experimentais/tratamento farmacológico , Compostos Organometálicos/farmacologia , Telômero/efeitos dos fármacos , Animais , Antineoplásicos/administração & dosagem , Antineoplásicos/uso terapêutico , Cério/química , Dexametasona/química , Quadruplex G , Humanos , Hidrólise , Células MCF-7 , Camundongos , Nanopartículas/metabolismo , Compostos Organometálicos/administração & dosagem , Compostos Organometálicos/uso terapêutico , Telômero/química
5.
Nano Lett ; 20(10): 7350-7358, 2020 10 14.
Artigo em Inglês | MEDLINE | ID: mdl-32856923

RESUMO

Increasing penetration of antibacterial agents into biofilm is a promising strategy for improvement of therapeutic effect and slowdown of the progression of antibiotic resistance. Herein, we design a near-infrared (NIR) light-driven nanoswimmer (HSMV). Under NIR light irradiation, HSMV performs efficient self-propulsion and penetrates into the biofilm within 5 min due to photothermal conversion of asymmetrically distributed AuNPs. The localized thermal (∼45 °C) and thermal-triggered release of vancomycin (Van) leads to an efficient combination of photothermal therapy and chemotherapy in one system. The active motion of HSMV increases the effective distance of photothermal therapy (PTT) and also improves the therapeutic index of the antibiotic, resulting in superior biofilm removal rate (>90%) in vitro. Notably, HSMV can eliminate S. aureus biofilms grown in vivo under 10 min of laser irradiation without damage to healthy tissues. This work may shed light on therapeutic strategies for in vivo treatment of biofilm-associated infections.


Assuntos
Nanopartículas Metálicas , Staphylococcus aureus , Antibacterianos/farmacologia , Biofilmes , Ouro , Fototerapia
6.
J Environ Manage ; 278(Pt 2): 111544, 2021 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-33129025

RESUMO

The popularity of Internet technology has resulted in people's lives being increasingly embedded in this network. The rise in usage of environmental protection apps has become a powerful tool in driving offline environmental protection activities and green lifestyles. However, little is known about the public's online green behavior. To fill this gap, we took Ant Forest, the most influential online environmental protection project in China, as a case study to explore the driving psychology of Ant Forest users' continuous use behaviors (CUBs) by expanding the use and gratifications theory. The proposed hypotheses were tested using a structural equation model based on data from 951 Ant Forest users. The results showed that users' gratification is an important psychological motivation that encourages CUBs in Ant Forest, and the different dimensions of gratification have significant differences in the driving intensity of the three types of CUBs. Moreover, emotional dependence moderates the relationships between gratifications and CUBs. Finally, from the perspective of cultivating gratification, this study suggests promoting the continuous use of Ant Forest as it provides a reference for understanding and developing online green behavior.


Assuntos
Formigas , Animais , China , Conservação dos Recursos Naturais , Florestas , Humanos , Prazer
7.
Small ; 15(42): e1903323, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31468717

RESUMO

Nanodrug-based cancer therapy is impeded by poor penetration into deep tumor tissues mainly due to the overexpression of hyaluronic acid (HA) in the tumor extracellular matrix (ECM). Although modification of nanoparticles (NPs) with hyaluronidase (HAase) is a potent strategy, it remains challenging to get a uniform distribution of drug at the tumor site because of the internalization of NPs by the cells in the tumor and HA regeneration. Herein, an intelligent nanocarrier, which can release HAase in response to the acidic tumor microenvironment (pH 6.5) and perform a strong neighboring effect with size reduction to overcome the above two problems and accomplish drug deep tumor penetration in vivo, is reported. In this design, HAase is encapsulated on the surfaces of doxorubicin (DOX) preloaded ZnO-DOX NPs using a charge convertible polymer PEG-PAH-DMMA (ZDHD). The polymer can release HAase to degrade HA in the tumor ECM (pH 6.5). ZnO-DOX NPs can release DOX in lysosomes (pH 4.5) to induce cell apoptosis, and exert a neighboring effect with size reduction to infect neighboring cells. The hierarchical targeted release of HAase and drugs is demonstrated to enhance tumor penetration and decrease side effects in vivo. This work shows promise for further application of ZDHD NPs in cancer therapy.


Assuntos
Portadores de Fármacos/química , Nanopartículas/química , Neoplasias/tratamento farmacológico , Animais , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Doxorrubicina/farmacologia , Doxorrubicina/uso terapêutico , Ácido Hialurônico/química , Hialuronoglucosaminidase/metabolismo , Camundongos Nus , Nanopartículas/ultraestrutura , Neoplasias/patologia , Polímeros/química , Esferoides Celulares/efeitos dos fármacos , Esferoides Celulares/patologia , Óxido de Zinco/química
8.
Chemistry ; 25(51): 11852-11858, 2019 Sep 12.
Artigo em Inglês | MEDLINE | ID: mdl-31361361

RESUMO

Proteolysis of amyloid-ß (Aß) is a promising approach against Alzheimer's disease. However, it is not feasible to employ natural hydrolases directly because of their cumbersome preparation and purification, poor stability, and hazardous immunogenicity. Therefore, artificial enzymes have been developed as potential alternatives to natural hydrolases. Since specific cleavage sites of Aß are usually embedded inside the ß-sheet structures that restrict access by artificial enzymes, this strongly hinders their efficiency for practical applications. Herein, we construct a NIR (near-IR) controllable artificial metalloprotease (MoS2 -Co) using a molybdenum disulfide nanosheet (MoS2 ) and a cobalt complex of 1,4,7,10-tetraazacyclododecane-1,4,7,10-tetraacetic acid (Codota). Evidenced by detailed experimental and theoretical studies, the NIR-enhanced MoS2 -Co can circumvent the restriction by simultaneously inhibition of ß-sheet formation and destroying ß-sheet structures of the preformed Aß aggregates in living cell. Furthermore, our designed MoS2 -Co is an easy to graft Aß-target agent that prevents misdirected or undesirable hydrolysis reactions, and has been demonstrated to cross the blood brain barrier. This method can be adapted for hydrolysis of other kinds of amyloids.


Assuntos
Peptídeos beta-Amiloides/química , Barreira Hematoencefálica/metabolismo , Dissulfetos/química , Metaloproteases/química , Molibdênio/química , Doença de Alzheimer , Barreira Hematoencefálica/química , Humanos , Metaloproteases/metabolismo , Espectrofotometria Infravermelho
9.
Geoderma ; 332: 190-197, 2018 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-30504969

RESUMO

In this study, different dosages of calcium polysulphide (CaSx) were used as an amendment to investigate effects on the immobilizing of Cd in a wetland soil by pot experiment. In addition to chemical analysis (pH and bioavailable Cd concentration), changes in soil enzyme activities, microbial carbon utilization capacity, metabolic and community diversity were examined to assess dynamic impacts on soil environmental quality and toxicity of Cd resulting from ameliorant dosing. Soil pH increased immediately upon CaSx amendment compared to the unamended control (CK), and then declined slowly to a level lower than CK. Diethylenetriamine pentaacetic acid (DTPA) extractable Cd concentration was determined to characterize the bioavailability of Cd in the soil. The CaSx dose-dependent effect observed that with increasing CaSx dosage, the immobilizing efficiency decreased. Soil urease and catalase activity assays and Biolog EcoPlate assay indicated that early stage addition of CaSx significantly inhibited soil microbial activities. However, mid and late stage time periods showed the inhibition effects were alleviated, and the microbial activities could be recovered in 1% and 2% CaSx treatments. Moreover, with increasing incubation time, microbial community diversity and richness were significantly recovered in 1% and 2% CaSx treatments compared to the CK. No considerable changes were observed in the 5% CaSx treatment. Conclusively, the 1% CaSx amendment was an efficient and safe dosage for the stabilization of Cd contaminated wetland soil. This study contributes to the development of in situ remediation ameliorants and technologies for heavy metal polluted wetland soils.

10.
J Am Chem Soc ; 139(45): 16201-16209, 2017 11 15.
Artigo em Inglês | MEDLINE | ID: mdl-29028335

RESUMO

Cancer stem cells (CSCs) are responsible for drug resistance, metastasis and recurrence of cancers. However, there is still no clinically approved drug that can effectively eradicate CSCs. Thus, it is crucial and important to develop specific CSC-targeting agents. Chiral molecular recognition of DNA plays an important role in rational drug design. Among them, polymorphic telomeric G-quadruplex DNA has received much attention due to its significant roles in telomerase activity and chromosome stability. Herein, we find that one enantiomer of zinc-finger-like chiral metallohelices, [Ni2L3]4+-P, a telomeric G-quadruplex-targeting ligand, can preferentially reduce cell growth in breast CSCs compared to the bulk cancer cells. In contrast, its enantiomer, [Ni2L3]4+-M, has little effect on both populations. Further studies indicate that [Ni2L3]4+-P can repress CSC properties and induce apoptosis in breast CSCs. This is different to the bulk cancer cells. The inhibition of breast CSC traits is involved in the nuclear translocation of hTERT. The apoptosis is associated with the induction of telomere uncapping, telomere DNA damage and the degradation of 3'-overhang. Moreover, [Ni2L3]4+-P, but not [Ni2L3]4+-M, has the ability to reduce tumorigenesis of breast CSCs in vivo. To our knowledge, this is the first report that chiral complexes show significant enantioselectivity on eradicating CSCs.


Assuntos
Apoptose/efeitos dos fármacos , Neoplasias da Mama/patologia , Células-Tronco Neoplásicas/efeitos dos fármacos , Células-Tronco Neoplásicas/patologia , Carcinogênese/efeitos dos fármacos , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Dano ao DNA , Desenho de Fármacos , Quadruplex G/efeitos dos fármacos , Humanos , Células-Tronco Neoplásicas/enzimologia , Células-Tronco Neoplásicas/metabolismo , Telomerase/metabolismo , Telômero/efeitos dos fármacos , Telômero/genética
11.
Small ; 13(46)2017 12.
Artigo em Inglês | MEDLINE | ID: mdl-29024506

RESUMO

Polyphenol compounds, such as curcumin, rutin, rifampicin, can inhibit Aß aggregation and decrease reactive oxygen species (ROS), and have received much attention in recent years for Alzheimer's disease (AD) treatment. However, the excess metal ions in amyloid plaque can chelate to polyphenol compounds. It significantly declines the efficacy of polyphenol compounds when used in the clinic. In this report, a near-infrared (NIR)-caged upconversion responsive system UCNP@SiO2 @Cur/CQ is designed and synthesized to control drug sequential release by regulating NIR laser. When the system is irradiated at low intensity of the NIR laser, the caged metal chelator, clioquinol (CQ), is first released for removing free metal ions, which affects the efficacy of curcumin. Subsequently, the strongly caged curcumin is released with increasing the intensity of NIR light. In this way, the treatment efficacy of curcumin is improved. This NIR-caged drug release system can not only remove Cu2+ but also clean superfluous ROS. Therefore, developing controllable sequential drug releasing may provide clinical benefits of combination treatment of AD. To the best of our knowledge, this work reports for the first time that a sequentially controlled system can overcome the interference of metal ions on polyphenol compounds for AD treatment.


Assuntos
Amiloide/química , Liberação Controlada de Fármacos , Raios Infravermelhos , Peptídeos beta-Amiloides/análise , Animais , Sobrevivência Celular , Difusão Dinâmica da Luz , Nanopartículas/química , Nanopartículas/ultraestrutura , Células PC12 , Tamanho da Partícula , Ratos , Espécies Reativas de Oxigênio/metabolismo
12.
Chemistry ; 23(72): 18146-18150, 2017 Dec 22.
Artigo em Inglês | MEDLINE | ID: mdl-29131418

RESUMO

Stereoselectivity towards substrates is one of the most important characteristics of enzymes. Amino acids, as cofactors of many enzymes, play important roles in stereochemistry. Herein, chiral nanozymes were constructed by grafting a series of d- or l-amino acids onto the surfaces of ceria (cerium oxide) nanoparticles. We selected the most commonly used drug for combating Parkinson's disease, that is, 3,4-dihydroxyphenylalanine (DOPA) enantiomers, as examples for chiral catalysis. Through detailed kinetic studies of cerium oxide nanoparticles (CeNPs) modified with different eight amino acids, we found that phenylalanine-modified CeNP was optimal for the DOPA oxidation reaction and showed excellent stereoselectivity towards its enantiomers. l-Phenylalanine-modified CeNPs showed higher catalytic ability for oxidation of d-DOPA, while d-phenylalanine-modified CeNPs were more effective towards l-DOPA. Taken together, the results indicated that stereoselective nanozyme can be constructed by grafting nanoparticles with chiral molecules. This work may inspire better design of chiral nanozymes.


Assuntos
Antiparkinsonianos/química , Cério/química , Coenzimas/química , Di-Hidroxifenilalanina/química , Nanopartículas Metálicas/química , Fenilalanina/química , Catálise , Humanos , Cinética , Levodopa/química , Oxirredução , Tamanho da Partícula , Estereoisomerismo , Propriedades de Superfície
13.
J Oral Maxillofac Surg ; 75(3): 498-507, 2017 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-27725104

RESUMO

PURPOSE: To explore the potential use of concentrated growth factor (CGF) in the treatment of temporomandibular joint osteoarthritis (TMJ-OA). MATERIALS AND METHODS: Surgical defects were created bilaterally on the condylar cartilage and bone to induce TMJ-OA in goats. CGF was applied to the right joints (CGF group) and physiologic saline was applied to the left joints (unrepaired group). There was a 1-month period of observation after the operation. These joint specimens were evaluated and compared based on gross appearance and histopathologic observations with hematoxylin and eosin (HE). The histopathologic scores of the condylar cartilage and repaired tissue, including cartilage, bone, and connective tissues, were compared between the 2 groups using SPSS 17.0 software. RESULTS: The unrepaired condylar surface was uneven, whereas the CGF-repaired condylar surface appeared smoother and was covered by cartilage-like tissue. HE staining of the unrepaired condyle showed exposed subchondral bone covered with rare connective tissue and an inflammatory reaction, whereas the CGF-repaired condyle showed tissue repair and regeneration, with bone regeneration and cartilage and a covering of connective tissue over the operated surface. The histologic score of the CGF group was significantly lower than that of the unrepaired group (P = .0127). The CGF group exhibited a significantly larger area of new cartilage and bone generation than the unrepaired group (P = .008 and P = .002, respectively). CONCLUSION: CGF might play an important role in processes of the molecular response to TMJ-OA. It can mediate inflammation, protect the subchondral bone, assist cell proliferation, and induce tissue repair in TMJ-OA.


Assuntos
Peptídeos e Proteínas de Sinalização Intercelular/farmacologia , Osteoartrite/tratamento farmacológico , Transtornos da Articulação Temporomandibular/tratamento farmacológico , Animais , Modelos Animais de Doenças , Cabras , Osteoartrite/patologia , Transtornos da Articulação Temporomandibular/patologia
14.
Artigo em Inglês | MEDLINE | ID: mdl-27815076

RESUMO

This article has been withdrawn at the request of the authors and editor. The Publisher apologizes for any inconvenience this may cause. The full Elsevier Policy on Article Withdrawal can be found at https://www.elsevier.com/about/our-business/policies/article-withdrawal.

15.
Cytokine ; 83: 110-117, 2016 07.
Artigo em Inglês | MEDLINE | ID: mdl-27104804

RESUMO

Acute mountain sickness (AMS) is a dangerous hypoxic illness that can affect humans who rapidly reach a high altitude above 2500m. In the study, we investigated the changes of cytokines induced by plateau, and the acetazolamide (ACZ) influenced the cytokines in rats exposed to high altitude. Wistar rats were divided into low altitude (Control), high altitude (HA), and high altitude+ACZ (22.33mg/kg, Bid) (HA+ACZ) group. The rats were acute exposed to high altitude at 4300m for 3days. The HA+ACZ group were given ACZ by intragastric administration. The placebo was equal volume saline. The results showed that hypoxia caused the heart, liver and lung damage, compared with the control group. Supplementation with ACZ significantly alleviated hypoxia-caused damage to the main organs. Compared with the HA group, the biochemical and blood gas indicators of the HA+ACZ group showed no difference, while some cytokines have significantly changed, such as activin A, intercellular adhesion molecule-1 (ICAM-1, CD54), interleukin-1α,2 (IL-1α,2), l-selectin, monocyte chemotactic factor (MCP-1), CC chemokines (MIP-3α) and tissue inhibitor of matrix metalloproteinase 1 (TIMP-1). Then, the significant difference pro-inflammatory cytokines in protein array were chosen for further research. The protein and mRNA content of pro-inflammatory cytokines MCP-1, interleukin-1ß (IL-1ß), tumor necrosis factor (TNF-α), interferon-γ (IFN-γ) in rat lung were detected. The results demonstrated that the high altitude affected the body's physiological and biochemical parameters, but, ACZ did not change those parameters of the hypoxia rats. This study found that ACZ could decrease the content of pro-inflammatory cytokines, such as MCP-1, IL-1ß, TNF-α and IFN-γ in rat lungs, and, the lung injury in the HA+ACZ group reduced. The mechanism that ACZ protected hypoxia rats might be related to changes in cytokine content. The reducing of the pro-inflammatory cytokines in rat lung might be other reason to explain ACZ against the acute mountain sickness.


Assuntos
Acetazolamida/farmacologia , Doença da Altitude/metabolismo , Citocinas/metabolismo , Lesão Pulmonar/metabolismo , Doença da Altitude/tratamento farmacológico , Animais , Masculino , Ratos , Ratos Wistar
16.
J Oral Maxillofac Surg ; 73(5): 943-50, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-25883002

RESUMO

PURPOSE: To establish a goat model for traumatic temporomandibular joint (TMJ) and describe the gross appearance and histopathologic changes for the prognostic comparison of different types of TMJ trauma. MATERIALS AND METHODS: According to clinical traumatic types, 16 adult goats were randomly divided into 4 groups based on outcome of surgical induction: 1) disc displacement without reduction (DD), 2) condylar cartilage defect (CCD), 3) DD plus CCD, and 4) control. TMJs were removed and observed 2 weeks and 1 month after the operation. These specimens were compared and evaluated based on gross appearance and histopathologic observations with hematoxylin and eosin and toluidine blue stains. The histopathologic score of condylar cartilage was observed and compared across the 4 groups using SPSS 17.0 software. RESULT: Three traumatic TMJ goat models were successfully established. At 2 weeks and 1 month after surgical induction, the DD group showed slightly irregular cartilage compared with the C group, with disordered cartilage composition, little angiogenesis, and proteoglycan degradation. The CCD group showed fibrous adhesion between the condyle and the disc without reparative cartilage tissues; the remaining cartilage was normal in composition and proteoglycan content. The DD + CCD group showed fibrous adhesions and irregular condylar cartilage with disordered cartilage composition and decreased matrix proteoglycans. The scores of cartilage degeneration among the 4 groups showed significant differences at 2 weeks and 1 month (DD + CCD > DD > CCD; P < .05). CONCLUSION: Among the 3 traumatic TMJ models, DD plus CCD can cause osteoarthritis (OA) and adhesions in the joint, DD can cause only OA, and CCD with the disc in normal position merely affects the remnant cartilage.


Assuntos
Modelos Animais de Doenças , Transtornos da Articulação Temporomandibular/patologia , Ferimentos e Lesões/patologia , Animais , Cabras , Manejo de Espécimes
17.
Guang Pu Xue Yu Guang Pu Fen Xi ; 35(11): 3028-31, 2015 Nov.
Artigo em Zh | MEDLINE | ID: mdl-26978901

RESUMO

A series of Sr3 (PO4)2: Eu²âº blue phosphors were synthesized by high temperature solid state method under N2-H2 reducing atmosphere. The crystal structures, excitation and emission spectra were characterized by X-ray diffraction (XRD) and Photoluminescence (PL), respectively. The results show that the Sr3 (PO4)2: Eu²âº phosphor can be efficiently excited by the wavelengths ranging from 310 to 390 nm, and the excitation peak wavelength locates at 359 nm. A wide emission spectrum (~150 nm, originating from the 4ƒ 5d¹-->4ƒ of the Eu²âº) with a peaking wavelength of 438 nm was obtained. Through the Gaussian fitting, we found that the emission band formed by two luminescence centers(430 and 459 nm), which indicated that the Eu²âº occupied two different Sr²âº sites in the substrate of Sr3(PO4)2. As the Eu²âº doping concentration is 7%, the maximum luminous intensity was obtained. With the increasing of the doping concentration of the Eu²âº, the concentration quenching effect occurred, and the emission peak wavelength has a red shift. The PL intensity of the Sr3 (PO4)2: Eu²âº phosphor is about 1.3 times than that of the blue emitting phosphor BaMgAl10O17: Eu²âº (BAM) which means that it is a promising candidate for the blue phosphor material for white LED.

18.
Environ Technol ; : 1-13, 2024 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-38429873

RESUMO

Because of its extreme toxicity and health risks, hexavalent chromium [Cr(VI)] has been identified as a major environmental contaminant. Bioreduction is considered as one of effective techniques for cleaning up Cr(VI)-contaminated sites, but the remediation efficiency needs to be enhanced. Here, a novel immobilized microbial agent was produced by immobilizing Bacillus cereus ZY-2009 with sodium alginate (SA) using polyvinyl alcohol (PVA) and activated carbon (AC). To evaluate the decrease of Cr(VI) by immobilized bacterial agents, batch tests were conducted with varying immobilization conditions, immobilization carriers, and dosages of medication. The removal of Cr(VI) by the agent prepared by the composite immobilization method was better than that by the adsorption and encapsulation methods. The optimal preparation conditions were the fraction of magnetic PVA was 5.00%, the fraction of SA was 4.00%, the fraction of CaCl2 was 4.00%, and the calcification time was 12 h. The experimental results indicated that PVA/SA/AC agents accelerated the reduction rate of Cr(VI). The removal rate of Cr(VI) by immobilized cells (90.5%) under ideal conditions was substantially higher than that of free cells (11.0%). This novel agent had a large specific surface area and a rich pore structure, accounting for its high reduction rate. The results suggest that the PVA/SA/AC immobilized Bacillus cereus ZY-2009 agent has great potential to remove Cr(VI) from wastewater treatment systems.

19.
J Hazard Mater ; 471: 134333, 2024 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-38643581

RESUMO

Microplastics (MPs) are emerging contaminants found globally. However, their effects on soil-plant systems in salt-affected habitats remain unknown. Here, we examined the effects of polyethylene (PE) and polylactic acid (PLA) on soil properties, maize performance, and bacterial communities in soils with different salinity levels. Overall, MPs decreased soil electrical conductivity and increased NH4+-N and NO3--N contents. Adding NaCl alone had promoting and inhibitive effects on plant growth in a concentration-dependent manner. Overall, the addition of 0.2% PLA increased shoot biomass, while 2% PLA decreased it. Salinity increased Na content and decreased K/Na ratio in plant tissues (particularly roots), which were further modified by MPs. NaCl and MPs singly and jointly regulated the expression of functional genes related to salt tolerance in leaves, including ZMSOS1, ZMHKT1, and ZMHAK1. Exposure to NaCl alone had a slight effect on soil bacterial α-diversity, but in most cases, MPs increased ACE, Chao1, and Shannon indexes. Both MPs and NaCl altered bacterial community composition, although the specific effects varied depending on the type and concentration of MPs and the salinity level. Overall, PLA had more pronounced effects on soil-plant systems compared to PE. These findings bridge knowledge gaps in the risks of MPs in salt-affected habitats.


Assuntos
Bactérias , Microplásticos , Microbiologia do Solo , Poluentes do Solo , Solo , Zea mays , Poluentes do Solo/toxicidade , Solo/química , Microplásticos/toxicidade , Zea mays/efeitos dos fármacos , Zea mays/crescimento & desenvolvimento , Bactérias/genética , Bactérias/efeitos dos fármacos , Bactérias/metabolismo , Bactérias/classificação , Cloreto de Sódio/toxicidade , Poliésteres , Salinidade , Polietileno , Microbiota/efeitos dos fármacos
20.
Environ Technol ; : 1-15, 2024 Jun 14.
Artigo em Inglês | MEDLINE | ID: mdl-38875356

RESUMO

Petroleum hydrocarbons as pervasive pollutants pose a significant threat to soil ecology and human health. Surfactant washing as an established technique can effectively remediate soils contaminated by hydrocarbons. Biosurfactants, which combine the properties of surfactants and environmental compatibility, have attracted increasing interest. However, due to the high production cost of biosurfactants, their practical application is restricted. This study addressed these limitations by selecting two biosurfactants, ß-cyclodextrin (C1) and sodium carboxymethyl cellulose (C2), and developed a promising cleaning agent formula through compounding and the addition of suitable additives. When the volume ratio of C1 to C2 was 8:2 and an 8 g/L mixture of sodium humate and sodium carbonate electrolyte was added, the surfactant system's surface tension reached a minimum, yielding optimal oil removal. The formation and synergistic behaviour of mixed micelles of surfactants were explained using ideal solution theory and the Rubingh model. By optimising the oil washing process parameters - normal temperature of 25 °C, pH 11, washing time of 2 h, solid-liquid ratio of 1:5, and oscillation frequency of 200 r/min - the oil removal rate achieved 76%. This cleaning agent, characterised by low production cost, straightforward application, environmental compatibility, and rapid, significant cleaning effect, shows potential for field-scale purification of petroleum-contaminated soil.

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