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1.
Nanomedicine ; 28: 102211, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32320736

RESUMO

Melanin-based nanoplatforms are biocompatible nanomaterials with a variety of unique physicochemical properties such as strong photothermal conversion ability, excellent drug binding capacity, strong metal chelation capacity, high chemical reactivity and versatile adhesion ability. These innate talents not only make melanin-based nanoplatforms be an inborn theranostic nanoagent for photoacoustic imaging-guided photothermal therapy of cancers, but also enable them to be conveniently transferred into cancer-targeting drug delivery systems and multimodality imaging nanoprobes. Due to the intriguing properties, melanin-based nanoplatforms have attracted much attention in investigations of cancer diagnosis and therapy. This review provides an overview of recent research advances in applications of melanin-based nanoplatforms in the fields of cancer diagnosis and therapy including cancer photothermal therapy, anticancer drug delivery, cancer-specific multimodal imaging and theranostics, etc. The remaining challenges and prospects of melanin-based nanoplatforms in biomedical applications are discussed at the end of this review.


Assuntos
Melaninas/química , Nanoestruturas/química , Neoplasias/diagnóstico , Neoplasias/tratamento farmacológico , Animais , Humanos , Indóis/química , Polímeros/química
2.
Am J Orthod Dentofacial Orthop ; 151(3): 565-571, 2017 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-28257741

RESUMO

INTRODUCTION: Although the association between orthognathic surgery and oral health-related quality of life (OHRQoL) has been explored, few studies have been carried out to describe the influence of surgery type on perceived OHRQoL. The aim of this study was to evaluate the difference of OHRQoL between a surgery-first approach and an orthodontics-first approach, using the 14-item Oral Health Impact Profile questionnaire (Chinese version). METHODS: Fifty adult Chinese orthodontic patients who received either surgery-first or orthodontics-first treatment completed 5 distinct sections of the questionnaire. Chi-square tests were used to compare categorical variables. All analyses were carried out with Stata software (version 11.2; StataCorp, College Station, Tex). RESULTS: The quality of life significantly improved after treatment in both groups. However, overall scores were highest before treatment in the surgery-first group but increased significantly from before treatment to 6 months after surgery and then significantly decreased after surgery in the orthodontics-first group. There were relatively lower scores in the surgery-first group than in the orthodontics-first group before surgery, at 12 months after beginning orthodontics, and at the end of treatment, although these differences did not reach significant levels. CONCLUSIONS: Both treatment methods can obtain the same results. The timing of the orthognathic approach did not affect the final OHRQoL in Chinese orthognathic surgery patients.


Assuntos
Saúde Bucal , Procedimentos Cirúrgicos Ortognáticos , Qualidade de Vida , Adulto , China , Feminino , Humanos , Masculino , Ortodontia Corretiva , Satisfação do Paciente , Inquéritos e Questionários
3.
Mar Pollut Bull ; 201: 116261, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38537567

RESUMO

Marine microorganisms have been reported to degrade microplastics. However, the degradation mechanisms are still poorly understood. In this study, a bacterium Roseibium aggregatum ZY-1 was isolated from seawater, which can degrade poly(butylene adipate-co-terephthalate) (PBAT). The PBAT-PLA(polylactic acid, PLA) films, before and after degradation, were characterized by scanning electron microscope (SEM) and Fourier transform infrared spectrometer (FTIR), the weight loss rate and water contact angle were measured. The results indicate that ZY-1 colonized on PBAT-PLA film, changed the functional groups and decreased water contact angle of PBAT-PLA film. Moreover, liquid chromatography mass spectrometry (LC-MS) analysis reveales that PBAT was degraded into its oligomers (TB, BTB) and monomers (T, A) during 10 days, and adipic acid (A) could be used as a sole carbon source. The whole genome sequencing analyses illustrate the mechanisms and enzymes such as PETase, carboxylesterases, arylesterase (PpEst) and genes like pobA, pcaBCDFGHIJKT, dcaAEIJK, paaGHJ involved in PBAT degradation. Therefore, the R. aggregatum ZY-1 will be a promising candidate of PBAT degradation.


Assuntos
Alcenos , Ácidos Ftálicos , Plásticos , Poliésteres , Poliésteres/química , Adipatos/química , Bactérias/metabolismo , Água
4.
Biomed Pharmacother ; 179: 117371, 2024 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-39216447

RESUMO

The continuous activation of macrophages play a critical role in the pathogenesis of cytokine storm (CS). Considering that CS results from the participation of multiple cytokines, the therapeutic effect of a single cytokine or its receptor-targeted blockade therapy remains uncertain. Melittin, which can systematically suppress the overexpression of proinflammatory mediators via inhibiting the mitogen-activated protein kinase and nuclear factor kappa-B pathways in activated macrophages, shows great potential in alleviating CS and acute inflammatory injury (AII). However, its clinical application is limited by its hemolytic activity, non-specific cytotoxicity and lack of targeting. In this study, a folic acid-modified and melittin stable-loaded solid lipid nanoparticle (Fa-MpG@LNP) with a core-shell structure was developed for CS control via targeted inhibition of the overproduction of proinflammatory mediators in activated macrophages with specific expression of folate receptor-ß. The resultant Fa-MpG@LNP showed ideal physicochemical properties and stability, low hemolytic activity and non-specific cytotoxicity, and it can specifically bind to lipopolysaccharide (LPS)-stimulated macrophages and effectively reduce the elevated levels of proinflammatory mediators. After intravenous administration, the Fa-MpG@LNP accumulated at inflamed tissue and significantly downregulate the overproduction of proinflammatory cytokines in tissue-infiltrated macrophages, resulting in a significant decrease of cytokine concentration in inflamed tissue and serum in LPS-induced acute pneumonia mice, and finally alleviate AII with undetectable toxic side effects. These results indicate the clinical application potential of Fa-MpG@LNP in alleviating CS and its related symptoms.


Assuntos
Síndrome da Liberação de Citocina , Citocinas , Macrófagos , Meliteno , Nanopartículas , Animais , Meliteno/farmacologia , Meliteno/administração & dosagem , Camundongos , Nanopartículas/química , Macrófagos/efeitos dos fármacos , Macrófagos/metabolismo , Citocinas/metabolismo , Síndrome da Liberação de Citocina/tratamento farmacológico , Células RAW 264.7 , Masculino , Lipopolissacarídeos , Inflamação/tratamento farmacológico , Inflamação/patologia , Lipídeos/química , Ácido Fólico/química , Camundongos Endogâmicos C57BL , Mediadores da Inflamação/metabolismo , Lipossomos
5.
Biomolecules ; 12(1)2022 01 12.
Artigo em Inglês | MEDLINE | ID: mdl-35053266

RESUMO

Melittin (MEL) is a 26-amino acid polypeptide with a variety of pharmacological and toxicological effects, which include strong surface activity on cell lipid membranes, hemolytic activity, and potential anti-tumor properties. However, the clinical application of melittin is restricted due to its severe hemolytic activity. Different nanocarrier systems have been developed to achieve stable loading, side effects shielding, and tumor-targeted delivery, such as liposomes, cationic polymers, lipodisks, etc. In addition, MEL can be modified on nano drugs as a non-selective cytolytic peptide to enhance cellular uptake and endosomal/lysosomal escape. In this review, we discuss recent advances in MEL's nano-delivery systems and MEL-modified nano drug carriers for cancer therapy.


Assuntos
Meliteno , Neoplasias , Portadores de Fármacos/química , Humanos , Lipossomos/uso terapêutico , Meliteno/farmacologia , Sistemas de Liberação de Fármacos por Nanopartículas , Neoplasias/tratamento farmacológico
6.
ACS Appl Mater Interfaces ; 13(47): 55902-55912, 2021 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-34793125

RESUMO

Melittin is a potential anticancer candidate with remarkable antitumor activity and ability to overcome tumor drug resistance. However, the clinical applications of melittin are largely restricted by its severe hemolytic activity and nonspecific cytotoxicity after systemic administration. Here, a biocompatible and stable melittin-loaded lipid-coated polymeric nanoparticle (MpG@LPN) formulation that contains a melittin/poly-γ-glutamic acid nanoparticle inner core, a lipid membrane middle layer, and a polyethylene glycol (PEG) and PEG-targeting molecule outer shell was designed. The formulations were prepared by applying a self-assembly procedure based on intermolecular interactions, including electrostatic attraction and hydrophobic effect. The core-shell MpG@LPN presented high efficiency for melittin encapsulation and high stability in physiological conditions. Hemolysis and cell proliferation assays showed that the PEG-modified MpG@LPN had almost no hemolytic activity and nonspecific cytotoxicity even at high concentrations. The modification of targeting molecules on the MpG@LPNs allowed for the selective binding with target tumor cells and cytolytic activity via apoptosis induction. In vivo experiments revealed that MpG@LPNs can remarkably inhibit the growth of tumors without the occurrence of hemolysis and tissue toxicity. Results suggested that the developed MpG@LPN with a core-shell structure can effectively address the main obstacles of melittin in clinical applications and has great potential in cancer treatment.


Assuntos
Antineoplásicos/farmacologia , Materiais Revestidos Biocompatíveis/farmacologia , Meliteno/farmacologia , Nanopartículas/química , Células A549 , Animais , Antineoplásicos/síntese química , Antineoplásicos/química , Proliferação de Células/efeitos dos fármacos , Materiais Revestidos Biocompatíveis/síntese química , Materiais Revestidos Biocompatíveis/química , Portadores de Fármacos/química , Ensaios de Seleção de Medicamentos Antitumorais , Feminino , Hemólise/efeitos dos fármacos , Humanos , Lipídeos/química , Meliteno/química , Camundongos , Camundongos Nus , Neoplasias Experimentais/tratamento farmacológico , Neoplasias Experimentais/metabolismo , Neoplasias Experimentais/patologia , Tamanho da Partícula , Polietilenoglicóis/síntese química , Propriedades de Superfície
7.
ACS Appl Bio Mater ; 4(3): 2821-2828, 2021 03 15.
Artigo em Inglês | MEDLINE | ID: mdl-35014321

RESUMO

In this study, a catalytic polydopamine-remodeling gold nanoparticle sensitized with an antinucleolin AS1411 probe (pAu nanoprobe) is synthesized, where the surface of the gold nanoparticles (AuNPs) is modified with a spontaneous self-polymerization of a polydopamine coating that imparts the probe functionalization ability and antispecific protein binding while the intrinsic catalytic property of the AuNPs is preserved. The functionalized AS1411 probe exerts specific recognition with nucleolin protein that is found to be overexpressed on the surface of breast cancer cells (MDA-MB-231). Scanning electron microscopy (SEM) confirms that the specific binding of the pAu nanoprobe occurs at the cancer cell surface. Taking advantage of the catalytic ability of the pAu nanoprobe in reducing blue-colored methylene blue (MB) to colorless leuco-MB, a colorimetric biosensing platform is established based on the accessible catalytic active sites on the pAu nanoprobe toward MB. The specific binding inhibits the pAu nanoprobe from efficiently catalyzing the reduction of MB, resulting in a "turn-off" catalytic biosensing platform. The catalytic conversion of MB is inversely proportional to the concentration of the nucleolin protein and the cancer cells, yielding a detection limit of 15 pM of the nucleolin protein and two cancer cells. The presence of five orders of magnitude higher concentration of bovine serum albumin hardly affects the catalytic ability of the pAu nanoprobe, that is, 88% catalytic ability is still preserved, which validates the specificity of the proposed pAu nanoprobe. In particular, a distinct color contrast creates a significant signal-to-noise ratio so as to enable single-cell level detection of two cancer cells by naked-eye judgment. Moreover, the undiluted, real human serum samples spiked with the cancer cells were examined with an impressive recovery of 94 ± 0.3%, which holds great promise in cancer cell screening.


Assuntos
Aptâmeros de Nucleotídeos/química , Materiais Biocompatíveis/química , Neoplasias da Mama/diagnóstico , Ouro/química , Indóis/química , Nanopartículas Metálicas/química , Oligodesoxirribonucleotídeos/química , Polímeros/química , Análise de Célula Única , Animais , Técnicas Biossensoriais , Catálise , Bovinos , Células Cultivadas , Humanos , Teste de Materiais , Estrutura Molecular , Tamanho da Partícula , Fosfoproteínas/análise , Proteínas de Ligação a RNA/análise , Soroalbumina Bovina/análise , Nucleolina
8.
Sci Rep ; 10(1): 989, 2020 01 22.
Artigo em Inglês | MEDLINE | ID: mdl-31969644

RESUMO

Hand, foot, and mouth disease (HFMD) is a common childhood illness caused by enteroviruses. We analyzed the pathogenic characteristics of HFMD in Shaanxi province, China, during 2010-2016. Clinical samples were collected from HFMD cases. Real-time PCR and RT-PCR were used to identify the enterovirus(EVs) serotypes. Viral RNA sequences were amplified using RT-PCR and compared by phylogenetic analysis. Descriptive epidemiological methods were used to analyze. A total of 16,832 HFMD positive cases were confirmed in the laboratory. EV-A71 and CV-A16 were the main pathogens in 2010. EV-A71 was the dominant pathogen in the periods of 2011 to 2012 and 2014, 2016. In 2013 and 2015, other EVs increased greatly, in which CV-A6 was the predominant pathogen. EV-A71 was more frequently detected in deaths and severe cases. Phylogenetic analysis revealed that EV-A71 belonged to the C4a evolution branch of C4 sub-genotype and CV-A16 belonged to the B1a or B1b evolution branch of B1 sub-genotype, whereas CV-A6 strains were assigned to D2 or D3 sub-genotype. The pathogen spectrum of HFMD has changed in 7 years, and the major serotypes EV-A71, CV- A16 and CV- A6 alternated or co-circulated. Long-term surveillance and research of EVs should be strengthened for the prevention and control of HFMD.


Assuntos
Enterovirus/isolamento & purificação , Doença de Mão, Pé e Boca/virologia , Criança , Pré-Escolar , China/epidemiologia , Feminino , Genótipo , Doença de Mão, Pé e Boca/epidemiologia , Humanos , Incidência , Lactente , Recém-Nascido , Masculino , RNA Viral , Sorogrupo
9.
Int J Nanomedicine ; 15: 483-495, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32158206

RESUMO

BACKGROUND: The complex preparation procedures and severe toxicities are two major obstacles facing the wide use of chimeric antigen receptor-modified T (CAR-T) cells in clinical cancer immunotherapy. The nanotechnology-based T cell temporary CAR modification may be a potential approach to solve these problems and make the CAR-T cell-based tumor therapy feasible and broadly applicable. METHODS: A series of plasmid DNA-loaded self-assembled nanoparticles (pDNA@SNPsx/y) prepared from adamantane-grafted polyamidoamine (Ad-PAMAM) dendrimers of different generations (G1 or G5) and cyclodextrin-grafted branched polyethylenimine (CD-PEI) of different molecular weights (800, 2000, or 25,000 Da) were characterized and evaluated. The detailed physicochemical properties, cellular interaction, and cytotoxicity of selected pDNA@SNPG1/800 were systematically investigated. Thereafter, the epidermal growth factor receptor variant III (EGFRvIII) CAR-expression plasmid vector (pEGFRvIII-CAR) was constructed and encapsulated into SNPG1/800. The resulting pEGFRvIII-CAR@SNPG1/800 was used for Jurkat cell transient transfection, and the EGFRvIII-CAR expressed in transfected cells was measured by flow cytometry and Western blot. Finally, the response of EGFRvIII CAR-positive Jurkat T cell to target tumor cell was evaluated. RESULTS: The pDNA@SNPG1/800 showed the highest efficacy in Jurkat cell gene transfection and exhibited low cytotoxicity. pEGFRvIII-CAR@SNPG1/800 can efficiently deliver pEGFRvIII-CAR into Jurkat T cells, thereby resulting in transient EGFRvIII-CAR expression in transfected cells. EGFRvIII-CAR that is present on the cell membrane enabled Jurkat T cells to recognize and bind specifically with EGFRvIII-positive tumor cells. CONCLUSION: These results indicated that pEGFRvIII-CAR@SNPG1/800 can effectively achieve T-cell transient CAR modification, thereby demonstrating considerable potential in CAR-T cancer therapy.


Assuntos
Receptores ErbB/genética , Técnicas de Transferência de Genes , Imunoterapia Adotiva/métodos , Nanopartículas/química , Linfócitos T/fisiologia , Linhagem Celular Tumoral , Dendrímeros/química , Vetores Genéticos , Humanos , Iminas/química , Imunoterapia , Células Jurkat , Peso Molecular , Polietilenos/química , Receptores de Antígenos de Linfócitos T/genética , Receptores de Antígenos de Linfócitos T/imunologia , Receptores de Antígenos Quiméricos/genética , Transfecção/métodos
10.
Yi Chuan ; 30(3): 347-51, 2008 Mar.
Artigo em Zh | MEDLINE | ID: mdl-18332005

RESUMO

In order to study the expression and regulation effects of estrogen receptor-beta (ERbeta) in the development of mouse embryo, the primer of ERbeta was designed, the ERbeta fragment was first obtained by RT-PCR and subcloned into plasmids pGEM- 3Z, then the recombinant plasmids were linearized with the restriction enzymes of EcoRand Hind. Using Sp6 and T7 RNA polymerase, the digoxigenin(dig) labeled sense and anti-sense probes were transcriped in vitro, respectively. Then the expression of ERbeta in mouse embryo was examined with the probes by whole-mount in situ hybridization. The results indicated that ERbeta is expressed in the brain, spinal neural tube, genital ridge, pericardium, limb bud and mandibular arch of 10.5 dpc embryo, and is also expressed in the telencephalon, mesencephalon, medulla oblongata, spinal cord and limb bud of 13.5 dpc embryo. These results suggest that ERbeta maybe play a role of regulation in sexual differentiation, primal differentiation of neural tube, further differentiation of three primary cerebral vesicles and spinal cord, generation and differentiation of bone and cartilage of limb bud, development of pericardium and configuration differentiation of mandibular in mouse embryo.


Assuntos
Clonagem Molecular/métodos , Embrião de Mamíferos/metabolismo , Receptor beta de Estrogênio/genética , Animais , Receptor beta de Estrogênio/fisiologia , Feminino , Hibridização In Situ , Camundongos , Plasmídeos/genética , Reação em Cadeia da Polimerase Via Transcriptase Reversa
11.
Arch Oral Biol ; 94: 84-92, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-29990589

RESUMO

OBJECTIVE: This study aimed to use cone-beam computed tomography (CBCT) to evaluate the root anatomy and canal morphology of maxillary premolars in a Chinese population and determine their degree of bilateral symmetry. DESIGN: 774 CBCT images were retrospectively analyzed, representing 1387 maxillary first premolars and 1403 second premolars. The number of roots and canals were recorded. The morphology of root canal systems was determined according to Vertucci's classification. The symmetry of root and canal anatomies between maxillary contralateral premolars was further evaluated. RESULTS: The most common anatomy of maxillary first and second premolars was one-rooted with two canals (58.0%) and one-rooted with one canal (50.3%), respectively. The typical canal morphology was type IV (42.7%) in maxillary first premolars and type I (50.3%) in maxillary second premolars. One-rooted maxillary premolars exhibited a higher variability in the canal morphology, compared to two-rooted or three-rooted teeth. Maxillary second premolars exhibited greater anatomic symmetry than first premolars. The root and canal numbers showed bilateral symmetry between 80.2% of maxillary first premolar pairs and 81.8% of second premolar pairs. Bilateral symmetry in both number and morphology of roots and canals was observed for 72.3% of maxillary first premolar pairs and 73.2% of second premolar pairs. CONCLUSION: The root anatomy and canal morphology of maxillary premolars in a Chinese population were quite diversified. Maxillary contralateral premolars demonstrated a high degree of symmetry in root and canal anatomies, which enables practitioners to better determine the nature of the root canal system during treatment of opposite homonymous teeth.


Assuntos
Dente Pré-Molar/anatomia & histologia , Tomografia Computadorizada de Feixe Cônico/métodos , Cavidade Pulpar/anatomia & histologia , Maxila/anatomia & histologia , Raiz Dentária/anatomia & histologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Povo Asiático , Dente Pré-Molar/diagnóstico por imagem , Cavidade Pulpar/diagnóstico por imagem , Feminino , Humanos , Masculino , Maxila/diagnóstico por imagem , Pessoa de Meia-Idade , Estudos Retrospectivos , Tratamento do Canal Radicular , Raiz Dentária/diagnóstico por imagem , Adulto Jovem
12.
Eur J Med Chem ; 92: 882-9, 2015 Mar 06.
Artigo em Inglês | MEDLINE | ID: mdl-25676729

RESUMO

Traditional chemotherapeutic drugs remain the major treatment for advanced colorectal cancer. However, due to the lack of tumor specificity these drug also destroy healthy tissue and organs, which has been the main reason for treatment failure and mortality. Folate-based drug delivery systems for improving nanoparticle endocytosis have been used to address these problems. Here, folic acid (FA) conjugated mPEG-b-P(CABCL-co-ACL) diblock copolymers were synthesized and characterized by TEM and NMR. Drug loaded nanoparticles were prepared using dialysis method and was obtained with a mean diameter of 45.2 nm with sustained in vitro release profile. In vitro cytotoxicity assay indicated that the cytotoxicity of folate modified nanoparticles were significantly increased compared to free drug and non-folate nanoparticles. In addition, results of hemolytic and histopathologic study suggested that the non-loaded nanoparticle (NL/NP) was non-toxic and biocompatible at the testing concentration. Moreover, in vivo results showed that FA/5-FU/NP effectively inhibited growth of HCT-8 cell-based xenograft tumors in BALB/c mice and revealed stronger antitumor efficacy than other treated groups. Thus, both in vitro and in vivo results exhibited that the folate conjugated mPEG-b-P(CABCL-co-ACL) copolymers have great potential to be used as sustainable and specific colon cancer targeting delivery system for anticancer agents.


Assuntos
Antineoplásicos/farmacologia , Fluoruracila/química , Nanopartículas/química , Neoplasias Experimentais/tratamento farmacológico , Animais , Antineoplásicos/síntese química , Antineoplásicos/química , Apoptose/efeitos dos fármacos , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Relação Dose-Resposta a Droga , Ensaios de Seleção de Medicamentos Antitumorais , Ácido Fólico/química , Células HCT116 , Humanos , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Neoplasias Experimentais/patologia , Polímeros/química , Relação Estrutura-Atividade
13.
Shanghai Kou Qiang Yi Xue ; 23(4): 419-22, 2014 Aug.
Artigo em Zh | MEDLINE | ID: mdl-25338790

RESUMO

PUPPOSE: To investigate Candida albicans and Streptococcus mutans adhesion to 3 polyurethane composites [pure polyurethane (PU), 1% polyphosphazene-containing polyurethane (PZS-1%) and 5% polyphosphazene-containing polyurethane (PZS-5%)]. METHODS: Two kinds of microorganism suspension were incubated with the specimens under certain culture conditions and the roughness of 3 materials were determined before adhesion tests. Microorganism attached to the specimen were then observed under optical microscope, and viable micro-organisms adhered to the specimen were then counted and removed. The data was analyzed with SAS 8.02 softwaree package. RESULTS: PU has the roughest surface followed by PZS-1% and PZS-5%. Most amounts of cell adhesion were observed in PU followed by PZS-1% and least amounts were found in PZS-5%. CONCLLUSIONS: The increase of polyphosphazene nanotubes in polyurethane composites may have an effect on cell adhesion. Surface roughness of the materials may be one of the factors.


Assuntos
Aderência Bacteriana , Poliuretanos , Propriedades de Superfície , Candida albicans , Adesão Celular , Humanos , Nanotubos , Compostos Organofosforados , Polímeros , Streptococcus mutans
14.
Huan Jing Ke Xue ; 35(1): 394-400, 2014 Jan.
Artigo em Zh | MEDLINE | ID: mdl-24720232

RESUMO

Super absorbent polymers (SAPs) are compounds that can absorb a lot of water which can be several folds of their original size and weight. They can increase soil water content and aggregates, promote fertilizer utilization efficiency, and stimulate crop growth. Therefore, SAPs have been widely regarded as a potential agent for water-saving agriculture. In this paper, we reviewed the advances of SAPs in materials, properties and applications in agriculture and pointed out that the absence of influences of SAPs on soil microbial ecology was the main issue in current studies. In regard to the adverse effects on soil environment caused by misuse of SAPs, we should address the systematic safety assessment of SAPs application in the soil, especially the effects on the soil microorganisms, which should be an important part of chemicals risk assessment in the soil application.


Assuntos
Agricultura , Polímeros/química , Solo/química , Água
15.
Huan Jing Ke Xue ; 35(2): 780-5, 2014 Feb.
Artigo em Zh | MEDLINE | ID: mdl-24812978

RESUMO

Super absorbent polymers (SAPs), a new water retention material, have a potential for application in water-saving agricultural production. In this study, we investigated the effects of SAPs, synthesized from natural plant extracts, on Chinese cabbage fresh weight, soil water content, soil water stable aggregates, soil microbial biomass (carbon) and soil microbial respiration under three water conditions (excessive, normal and deficient) and two SAPs application strategies (bulk treatment and spraying treatment). The results showed that the SAPs significantly promoted the soil water content, water-stable aggregates (> 0.25 mm) and the soil microbial activities, especially under the water deficient conditions. Meanwhile, SAP application strategy was of great significance to the effects on Chinese cabbage and soil properties. Compared with the control treatment under normal water condition, spraying treatment of Jaguar C (S-JC) could reduce irrigation water amount by about 25% without reducing the crop production. Furthermore, compared with the control treatment under the same water condition with S-JC (deficient), it could increase Chinese cabbage production by 287%. Thus, SAPs is an environmental friendly water-saving technique in agricultural production.


Assuntos
Agricultura/métodos , Brassica/crescimento & desenvolvimento , Polímeros/química , Água , Irrigação Agrícola , Biomassa , Solo , Microbiologia do Solo
17.
J Pharm Sci ; 103(4): 1064-74, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24523221

RESUMO

The principal limitations of chemotherapy are dose-limiting systemic toxicity and the development of multidrug-resistant phenotypes. The aim of this study was to investigate the efficiency of a new sustained drug delivery system based on chitosan and ε-caprolactone to overcome multidrug resistance in monolayer and drug resistance associated with the three-dimensional (3D) tumor microenvironment in our established 3D models. The 5-fluorouracil (5-FU)-loaded nanoparticles (NPs) were characterized by transmission electron microscope and dynamic light scattering, and its released property was determined at different pH values. 5-FU/NPs exhibited well-sustained release properties and markedly enhanced the cytotoxicity of 5-FU against HCT116/L-OHP or HCT8/VCR MDR cells in two-dimensional (2D) and its parental cells in 3D collagen gel culture with twofold to threefold decrease in the IC50 values, as demonstrated by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay, Hoechst/propidium iodide staining and flow cytometry analysis. Furthermore, the possible mechanism was explored by high-performance liquid chromatography and rhodamine 123 accumulation experiment. Overall, the results demonstrated that 5-FU/NPs increase intracellular concentration of 5-FU and enhance its anticancer efficiency by inducing apoptosis. It was suggested that this novel NPs are a promising carrier to decrease toxic of 5-FU and has the potential to reverse the forms of both intrinsic and acquired drug resistance in 2D and 3D cultures.


Assuntos
Antimetabólitos Antineoplásicos/administração & dosagem , Quitosana/química , Preparações de Ação Retardada/química , Fluoruracila/administração & dosagem , Nanopartículas/química , Poliésteres/química , Antimetabólitos Antineoplásicos/farmacocinética , Antimetabólitos Antineoplásicos/farmacologia , Linhagem Celular Tumoral , Quitosana/metabolismo , Preparações de Ação Retardada/metabolismo , Resistência a Múltiplos Medicamentos , Resistencia a Medicamentos Antineoplásicos , Fluoruracila/farmacocinética , Fluoruracila/farmacologia , Humanos , Nanopartículas/metabolismo , Neoplasias/tratamento farmacológico , Poliésteres/metabolismo
18.
Shanghai Kou Qiang Yi Xue ; 23(5): 561-5, 2014 Oct.
Artigo em Zh | MEDLINE | ID: mdl-25543598

RESUMO

PURPOSE: To observe the stimulating effect of pure traditional Chinese medical mouth rinse (PTCMMR) on skin and mucosa and to evaluate the efficacy of PTCMMR on inhibiting and killing oral common bacteria. METHODS: PTCMMR and normal saline (NS) were separately dripped onto 14 five-month rabbits' left and right eyes for 7 days, and were smeared on the left and right side of buttocks, abdomens, back of 10 seven-month guinea pigs (after hair removal) once a day for comparison between the two sides. Five animals were sacrificed after 3 and 7 days of smearing to make pathological sections. Bacterium suspension with Staphylococcus aureus, Escherichia coli, Candida albicans, Pseudomonas aeruginosa and Streptococcus B were dropped to nutrient solution containing different concentrations of PTCMMR or compound Borax solution to observe the growth situation of bacteria. Inhibition zone diameters were measured after 18h of incubation within 37 degrees centigrade incubator. The data was statistically analyzed using SPSS 17.0 software package. RESULTS: There was no obvious change such as redness, dermatitis between rabbits' left eye conjunctiva and the control group. The bacteriostatic and bactericidal effect of anaerobe and aerobe with dropping of PTCMMR was stronger than that of control group. CONCLUSIONS: PTCMMR has no stimulation to skin and mucosa, while it has strong efficacy to inhibit and kill oral common bacteria.


Assuntos
Antibacterianos , Staphylococcus aureus , Animais , Candida albicans , Cobaias , Boca , Mucosa , Pseudomonas aeruginosa , Coelhos
19.
Shanghai Kou Qiang Yi Xue ; 22(2): 237-9, 2013 Apr.
Artigo em Zh | MEDLINE | ID: mdl-23708045

RESUMO

Dental education in the Netherlands is composed of medical education and dental education. The most important things of the dental education in Netherlands are to foster students' independent learning and innovative spirit. Universities provide advanced facilities, reasonable curricular arrangement and characteristic education system. Great importance is attached to training students' practical skills and ability to apply knowledge to practice. Meanwhile, they developed a virtual digital system named Simodont, which optimize the pre-practice training and promote the training of diagnosis thinking and treatment skills. The advanced education system and approaches in the Netherlands are of great benefit to the stomatological education in China.


Assuntos
Educação em Odontologia , China , Humanos , Países Baixos
20.
Shanghai Kou Qiang Yi Xue ; 21(6): 677-82, 2012 Dec.
Artigo em Zh | MEDLINE | ID: mdl-23364555

RESUMO

PURPOSE: To investigate 98 fixed denture patients' personality traits and the relationship between patients' personality traits and satisfaction with fixed denture restoration. METHODS: 16PF questionnaire and satisfaction questionnaire were used to study 98 fixed denture patients' personality traits and the relationship between personality traits and general satisfaction and specific satisfaction. The data was analyzed with SPSS17.0 software package. RESULTS: There were significant differences between 98 fixed denture patients' personality traits and those of health adult in factor B(reasoning), C(emotional stability), E(dominance), F(liveliness), H(social Boldness), I(sensitivity), L(vigilance), N(privateness), O(apprehension), Q(1)(openness to change) and Q(2)(self-reliance). The regression analysis demonstrated that Q4(tension), G(rule-consciousness), L(vigilance), Q(3)(perfectionism), Q(1)(openness to change), N(privateness), A(warmth) and M(abstractedness)in 16PF were correlated with the general satisfaction of patients after fixed denture restorations (F=20.566' P=0.000, R2=0.649), Q(4), L, Q(3), N and M were negatively correlated with their general satisfaction; however G, Q(1) and A were positively correlated with it. Except the sense of stability and avoid of food impaction,L,C, Q(4) and Q(3) were negatively correlated with their satisfaction on aesthetic effectiveness, while A, G, I and E were positively correlated with it. L, Q(4), N and Q(3) were negatively correlated with their mastication satisfaction, while G and Q(1) were positively correlated with it. O and Q(4) were negatively correlated with their comfortable satisfaction, while C was positively correlated with it. CONCLUSIONS: There is significant difference in personality traits between fixed denture patients and Chinese normal adults. There is close relationship between the personality traits of fixed denture patients and their satisfaction. Meanwhile, the general and specific satisfaction are influenced by different personality traits. It is important to pay more attention to fixed denture patients' personality traits in clinical practice.


Assuntos
Dentaduras , Satisfação Pessoal , Adulto , Humanos , Mastigação , Personalidade , Inquéritos e Questionários
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