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1.
J Invertebr Pathol ; 203: 108066, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38246321

RESUMO

Ameson portunus, the recently discovered causative agent of "toothpaste disease" of pond-cultured swimming crabs in China has caused enormous economic losses in aquaculture. Understanding the process of spore germination is helpful to elucidate the molecular mechanism of its invasion of host cells. Here, we obtained mature and germinating spores by isolation and purification and in vitro stimulation, respectively. Then, non-germinated and germinated spores were subjected to the comparative transcriptomic analysis to disclose differential molecular responses of these two stages. The highest germination rate, i.e., 71.45 %, was achieved in 0.01 mol/L KOH germination solution. There were 9,609 significantly differentially expressed genes (DEGs), with 685 up-regulated and 8,924 down-regulated DEGs. The up-regulated genes were significantly enriched in ribosome pathway, and the down-regulated genes were significantly enriched in various metabolic pathways, including carbohydrate metabolism, amino acid metabolism and other metabolism. The results suggested that spores require various carbohydrates and amino acids as energy to support their life activities during germination and synthesize large amounts of ribosomal proteins to provide sites for DNA replication, transcription, translation and protein synthesis of the spores of A. portunus within the host cells. Functional genes related to spore germination, such as protein phosphatase CheZ and aquaporin, were also analyzed. The analysis of transcriptome data and identification of functional genes will help to understand the process of spore germination and invasion.


Assuntos
Microsporídios , Transcriptoma , Animais , Esporos , Microsporídios/genética , Perfilação da Expressão Gênica , Esporos Bacterianos/genética
2.
Zhongguo Zhong Yao Za Zhi ; 46(8): 1935-1942, 2021 Apr.
Artigo em Zh | MEDLINE | ID: mdl-33982502

RESUMO

Myrtus communis is a traditional medicinal aromatic plant in the Mediterranean. At present, the plant has been introduced and cultivated in the southern part of China, and it is mostly used for ornamental or cosmetic purposes. Based on literature analysis and the theory of Chinese medicine, we discussed the medicinal parts and properties of M. communis in this paper to provide a theoretical basis for exploring the medicinal value of M. communis and its compatibility with traditional Chinese medicines. Literatures were searched from Web of Science(core collection), PubMed, CNKI, VIP and Wanfang by using the set conditions as key words. Then the obtained literatures were screened and classified. Finally, a total of 376 articles were included, consisting of 44 reviews, 54 germplasm resources, 78 chemical researches, 48 studies on application, extraction, or quality, 18 human trials, 132 pharmacological studies, and 2 safety studies. Based on literature analysis and theories of Chinese medicine, the leaves of M. communis were finally selected as the medicinal part of Chinese medicine, and the traditional Chinese medicine properties of M. communis leaves were deduced as pungent, bitter, and cool. The channel tropisms of M. communis leaves included lung, liver, and large intestine, with functions of detoxifying, resolving a mass, and insecticide. It was used for mouth sores, vaginal itching, hemorrhoids and warts, etc.; appropriate amount shall be applied for external use, and the decoction form shall be used for washing the affected parts; 3-12 g equivalent product shall be used in decoction, and this herb shall be put into the decoction in a later stage. The clarification of the medicinal parts of M. communis, and the determination of the Chinese medicine properties of M. communis leaves would lay a theoretical foundation for its compatibility and application with Chinese medicines, and can do more contribution to the medical and healthcare industry in our country.


Assuntos
Medicamentos de Ervas Chinesas , Myrtus , Plantas Medicinais , China , Humanos , Medicina Tradicional Chinesa , Folhas de Planta
3.
J Gene Med ; 22(7): e3177, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32096291

RESUMO

BACKGROUND: Herpes simplex virus type 1 (HSV-1)-mediated oncolytic therapy is a promising cancer treatment modality. However, viral tropism is considered to be one of the major stumbling blocks to the development of HSV-1 as an anticancer agent. METHODS: The surface of oncolytic HSV-1 G207 was covalently modified with folate-poly (ethylene glycol) conjugate (FA-PEG). The specificities and tumor targeting efficiencies of modified or unmodified G207 particles were analyzed by a real-time polymerase chain reaction at the level of cell attachment and entry. Immune responses were assessed by an interleukin-6 release assay from RAW264.7 macrophages. Biodistribution and in vivo antitumoral activity after intravenous delivery was evaluated in BALB/c nude mice bearing subcutaneous KB xenograft tumors. RESULTS: FA-PEG-HSV exhibited enhanced targeting specificity for folate receptor over-expressing tumor cells and had lower immunogenicity than the unmodified HSV. In vivo, the FA-PEG-HSV group revealed an increased anti-tumor efficiency and tumor targeting specificity compared to the naked HSV. CONCLUSIONS: These results indicate that folate-conjugated HSV G207 presents a folate receptor-targeted oncolytic virus with a potential therapeutic value via retargeting to tumor cells.


Assuntos
Ácido Fólico/análogos & derivados , Ácido Fólico/química , Herpesvirus Humano 1 , Terapia Viral Oncolítica/métodos , Polietilenoglicóis/química , Células A549 , Administração Intravenosa , Animais , Linhagem Celular Tumoral , Chlorocebus aethiops , Receptores de Folato com Âncoras de GPI/química , Humanos , Imunidade , Interleucina-6/metabolismo , Células KB , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Células RAW 264.7 , Distribuição Tecidual , Células Vero , Internalização do Vírus
4.
J Nanobiotechnology ; 18(1): 146, 2020 Oct 19.
Artigo em Inglês | MEDLINE | ID: mdl-33076924

RESUMO

BACKGROUNDS: Surgical resection and adjunct chemotherapy or radio-therapy has been applied for the therapy of superficial malignant tumor in clinics. Whereas, there are still some problems limit its clinical use, such as severe pains and side effect. Thus, it is urgent need to develop effective, minimally invasive and low toxicity therapy stagey for superficial malignant tumor. Topical drug administration such as microneedle patches shows the advantages of reduced systemic toxicity and nimble application and, as a result, a great potential to treat superficial tumors. METHODS: In this study, microneedle (MN) patches were fabricated to deliver photosensitizer IR820 and chemotherapy agent cisplatin (CDDP) for synergistic chemo-photodynamic therapy against breast cancer. RESULTS: The MN could be completely inserted into the skin and the compounds carrying tips could be embedded within the target issue for locoregional cancer treatment. The photodynamic therapeutic effects can be precisely controlled and switched on and off on demand simply by adjusting laser. The used base material vinylpyrrolidone-vinyl acetate copolymer (PVPVA) is soluble in both ethanol and water, facilitating the load of both water-soluble and water-insoluble drugs. CONCLUSIONS: Thus, the developed MN patch offers an effective, user-friendly, controllable and low-toxicity option for patients requiring long-term and repeated cancer treatments.


Assuntos
Neoplasias da Mama/tratamento farmacológico , Cisplatino/farmacologia , Sistemas de Liberação de Medicamentos/métodos , Verde de Indocianina/farmacologia , Fotoquimioterapia/métodos , Animais , Antineoplásicos/farmacologia , Apoptose/efeitos dos fármacos , Neoplasias da Mama/patologia , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Liberação Controlada de Fármacos , Tratamento Farmacológico , Feminino , Humanos , Verde de Indocianina/análogos & derivados , Camundongos Endogâmicos BALB C , Fármacos Fotossensibilizantes/administração & dosagem , Povidona/análogos & derivados
5.
BMC Pediatr ; 20(1): 268, 2020 06 03.
Artigo em Inglês | MEDLINE | ID: mdl-32493254

RESUMO

BACKGROUND: Plastic bronchitis is an uncommon but severe respiratory disease characterized by formation of casts in tracheobronchial tree. It can lead to airway obstruction and even respiratory failure. CASE PRESENTATION: Plastic bronchitis is mostly seen in both post-cardiac surgery patients, especially Fontan procedure, and infections including those caused by influenza viruses, Mycoplasma pneumoniae or tuberculosis. But it has rarely been reported to be associated with adenovirus infection. We report 2 cases of plastic bronchitis arising from adenovirus serotype 7 infection, manifested in repeated high fever, cough, and progressive dyspnea, and were diagnosed and eventually cured by bronchoscopy. CONCLUSIONS: Plastic bronchitis is a rare, variable and potentially fatal disease. In the cases we described, the cause was associated with adenovirus serotype 7 and its treatment required intervention with bronchoscopy and adequate control of the underlying disease.


Assuntos
Bronquite , Adenoviridae , Bronquite/diagnóstico , Bronquite/etiologia , Broncoscopia , Criança , Humanos , Plásticos , Sorogrupo
6.
Bioprocess Biosyst Eng ; 43(9): 1599-1607, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32333194

RESUMO

Transaminase responsible for alienating prochiral ketone compound is applicable to asymmetric synthesis of herbicide L-phosphinothricin (L-PPT). In this work, the covalent immobilization of recombinant transaminase from Citrobacter koseri (CkTA) was investigated on different epoxy resins. Using optimum ES-105 support, a higher immobilized activity was obtained via optimizing immobilization process in terms of enzyme loading, coupling time and initial PLP concentration. Crucially, due to blocking unreacted epoxy groups on support surface with amino acids, the reaction temperature of blocked immobilized biocatalyst was enhanced from 37 to 57 °C. Its thermostability at 57 °C was also found to be superior to that of free CkTA. The Km value was shifted from 36.75 mM of free CkTA to 39.87 mM of blocked immobilized biocatalyst, demonstrating that the affinity of enzyme to the substrate has not been apparently altered. Accordingly, the biocatalyst performed the consecutive synthesis of L-PPT for 11 cycles (yields>91%) with retaining more than 91.13% of the initial activity. The seemingly the highest reusability demonstrates this biocatalyst has prospective for reducing the costs of consecutive synthesis of L-PPT with high conversion.


Assuntos
Aminobutiratos/síntese química , Proteínas de Bactérias/química , Citrobacter koseri/enzimologia , Enzimas Imobilizadas/química , Resinas Epóxi/química , Transaminases/química , Proteínas de Bactérias/genética , Citrobacter koseri/genética , Enzimas Imobilizadas/genética , Proteínas Recombinantes/química , Proteínas Recombinantes/genética , Transaminases/genética
8.
Zhonghua Nan Ke Xue ; 24(7): 613-617, 2018 07.
Artigo em Zh | MEDLINE | ID: mdl-30173444

RESUMO

Objective: To study the influence of povidone-iodine (PI) versus that of the benzethonium chloride wipe (BCW) on semen collection and semen quality of sperm donors undergoing penile skin disinfection and provide some evidence for the selection of disinfection methods for semen collection. METHODS: We used PI from August to December 2015 and BCWs from January to July 2016 for penile skin disinfection before semen collection, with two samples from each donor, one collected with and the other without penis skin disinfection (the blank control group). After semen collection, we conducted a questionnaire investigation on the influence of the two disinfection methods on semen collection and compared the semen parameters between the two groups of sperm donors. RESULTS: Totally, 185 sperm donors were included in this study, of whom 63 underwent penile skin disinfection with PI and the other 122 with BCWs before semen collection. Statistically significant differences were found between the PI and BCW groups in the adaptability to the disinfectant and rigid disinfection procedures (P <0.05), but not in the other items of the questionnaire (P >0.05). Compared with the sperm donors of the blank control group, those of the PI group showed statistically significant difference in the percentage of progressively motile sperm (PMS) (ï¼»63.02 ± 3.18ï¼½% vs ï¼»61.45 ± 4.78ï¼½%, P<0.05), but not in the abstinence time (ï¼»4.97 ± 1.79ï¼½ vs ï¼»4.7 ± 0.94ï¼½ d, P >0.05), semen volume (ï¼»4.11 ± 1.54ï¼½ vs ï¼»4.15 ± 1.61ï¼½ ml, P >0.05), sperm concentration (ï¼»110 ± 29.6ï¼½ vs ï¼»107.5 ± 31.79ï¼½ ×106/ml, P >0.05), or total sperm count (ï¼»439.10 ± 170.13ï¼½ vs ï¼»434.02 ± 186.91ï¼½ ×106/ejaculate, P >0.05), while those of the BCW group exhibited no remarkable difference in any of the above parameters (P >0.05). Among the samples with abnormal semen quality, significantly fewer were found with abnormal PMS in the BCW than in the PI group (1.64% ï¼»2/122ï¼½ vs 9.68% ï¼»6/62ï¼½, P <0.05). However, there were no significant differences between the PI and BCW groups in the abnormal semen volume, abnormal sperm concentration, or the rate of semen bacterial contamination (P >0.05). CONCLUSIONS: Before semen collection from donors, penile skin disinfection with povidone-iodine may affect both the semen collection process and the quality of donor sperm, while the benzethonium chloride wipe can reduce the influence on the semen collection process and does not affect the semen parameters.


Assuntos
Anti-Infecciosos Locais/administração & dosagem , Benzetônio/administração & dosagem , Desinfecção/métodos , Povidona-Iodo/administração & dosagem , Recuperação Espermática , Desinfecção/estatística & dados numéricos , Humanos , Masculino , Pênis , Sêmen , Análise do Sêmen , Pele , Contagem de Espermatozoides , Espermatozoides , Doadores de Tecidos
9.
Appl Microbiol Biotechnol ; 100(23): 10203-10213, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-27709289

RESUMO

Denitratation (nitrite produced from nitrate), has the potential applications in wastewater treatment by combining with ANAMMOX process. The occurrence of denitratation has been shown to be effected qualitatively by various parameters in the environment. A more quantitative understanding can be obtained using enrichment cultures in lab-scale experiments, yet information on the enrichment of functional microorganisms responsible for denitratation is lacking. In this study, a stable denitratation-dominated culture was obtained from methylotrophic denitrifying culture. The results showed that, besides the substitution of acetate for methanol, the lasting starvation following saturation of electron donor was another pivotal selection pressure that favored the growth of denitratating bacteria, which was supported by the distinctive physiological strategy involving the higher growth rate combining with larger poly-hydroxybutyrate (PHB) accumulation at sufficient electron donor situation and then manage the stress of electron donor starvation by consumpiton of the PHB. High-throughput 16S rRNA gene sequencing analysis indicated that non-methylotrophic Halomonas campisalis (48.1 %) and Halomonas campaniensis (30.4 %) dominated in the denitratating community. Moreover the denitratation was driven by the nitrate inhibiting the nirS transcription in the Halomonas species.


Assuntos
Bactérias/classificação , Metanol/metabolismo , Consórcios Microbianos , Nitratos/metabolismo , Nitritos/metabolismo , Acetatos/metabolismo , Bactérias/genética , Bactérias/crescimento & desenvolvimento , Biotransformação , DNA Bacteriano/química , DNA Bacteriano/genética , DNA Ribossômico/química , DNA Ribossômico/genética , Transporte de Elétrons , Hidroxibutiratos/metabolismo , Poliésteres/metabolismo , RNA Ribossômico 16S/genética , Análise de Sequência de DNA
10.
Yao Xue Xue Bao ; 51(4): 642-9, 2016 04.
Artigo em Zh | MEDLINE | ID: mdl-29860751

RESUMO

cRGD-carboxymethyl chitosan-palmitic acid (cRGD-CMCh-PA) was synthesized and a pH- sensitive paclitaxel-loaded cRGD-CMCh-PA micelles(PTX-cRGD-CMCh-PA) was prepared with the film dispersion method; related substances were characterized by FT-IR and (1)H NMR. PTX-cRGD-CMCh-PA micelles were studied with the particle size distribution, zeta potential, morphology and release behavior in vitro was investigated by the method of equilibrium dialysis. In vitro cytotoxicity of different formulations on A549 cells was tested by MTT assay. The uptake process of micelles was explored using confocal microscopy and a live cell station was used to observe the dynamic phagocytosis. The subcutaneous and orthotropic tumor models were built to study the distribution of Di R-labeled micelles by near-infrared fluorescence(NIR) imaging system. The FT-IR spectra and (1)H NMR spectra confirmed the successful conjugation of cRGD-CMCh-PA polymer and the degree of carboxymethyl and the palmitic acid grafted on chitosan were 45.0% and 15.0%. PTX-cRGD-CMCh-PA micelles were prepared with particle size of(162.9 ± 1.5) nm, zeta potential of +26.3 m V and encapsulation efficiency and the drug loading of 99.67% and 28.5%, respectively. The micelles released slowly in pH 7.4 whose release curves were accorded with the Higuchi equation; they had an initial burst effect in second hours and showed a pH sensitive release behavior in pH 5.3. The IC(50) of PXT-CMCh-PA and PTX-cRGD-CMCh-PA were 2.077 µg·mL(-1) and 0.876 µg·mL(-1), respectively. The cells uptake process of micelles in A549 cells revealed that the micelles were mainly co-located with lysosome and PTX-cRGD-CMCh- PA showed much better targeting effect. The NIR fluorescence imaging results showed that the micelles had a good targeting effect on both subcutaneous and orthotropic tumors. In this study, a novel copolymer cRGD- CMCh-PA was synthesized with a sustained and pH-dependent drug release activity which would potentially become a new carrier for hydrophobic drugs.


Assuntos
Quitosana/análogos & derivados , Portadores de Fármacos/química , Oligopeptídeos/química , Paclitaxel/administração & dosagem , Ácido Palmítico/química , Células A549 , Antineoplásicos Fitogênicos/administração & dosagem , Quitosana/química , Liberação Controlada de Fármacos , Humanos , Interações Hidrofóbicas e Hidrofílicas , Micelas , Tamanho da Partícula , Polímeros , Espectroscopia de Infravermelho com Transformada de Fourier
11.
Sichuan Da Xue Xue Bao Yi Xue Ban ; 47(6): 848-851, 2016 Nov.
Artigo em Zh | MEDLINE | ID: mdl-28598110

RESUMO

OBJECTIVES: To study the microbial community structure on the root surface of patients with periodontitis. METHODS: Bacterial plaque and tissues from the root neck (RN group),root middle (RM group) and root tine (RT group) of six teeth with mobility 3 in one patient with periodontitis were sampled.The V3V4 region of 16S rRNA was sequenced on the Illumina MiSeq platform.The microbial community structure was analyzed by Mothur,Qiime and SPSS software. RESULTS: The principal component analysis (PCoA) results indicated that the RM samples had a similar microbial community structure as that of the RT samples,which was significant different from that of the RN samples.Thirteen phyla were detected in the three groups of samples,which included 7 dominant phyla.29 dominant genera were detected in 184 genera.The abundance of Bacteroidetes_[G-6] and Peptostre ptococcaceae_[XI][G-4] had a positive correlation with the depth of the collection site of samples (P<0.05),while the abundance of Prevotella,Selenomonas,Corynebacterium and Olsenella had a negative correlation with the depth of the collection site of samples (P<0.05). CONCLUSIONS: There is region-specificity of microbial community structure on the root surface of patients with periodontitis.


Assuntos
Bactérias/classificação , Placa Dentária/microbiologia , Periodontite/microbiologia , Raiz Dentária/microbiologia , Humanos , RNA Ribossômico 16S/genética
12.
Fa Yi Xue Za Zhi ; 32(1): 69-73, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-27295861

RESUMO

A case of a stillbirth with lethal type II osteogenesis imperfecta (OI) was reported. The fetus had skull fractures and craniocerebral injuries during pregnancy. Postmortem multi-sliced computed tomography (MSCT) and 3D-reconstruction were performed, followed by a medico-legal autopsy. The autopsic findings showed the typical features of type II OI, including a soft calvarium, deformed extremities, flexed and abducted hips, and uncommon features, such as white sclera, coxa vara, absence of several bones and organs, a cleft lip, and asymmetric ears. The radiologic images revealed such anomalies and variations as a cleft palate, mandibular dysplasia, spina bifida, costa cervicalis, and fusion of the ribs and vertebrae, which were difficult to detect during conventional autopsy. The paper investigated the classification, causative mutation, cause of death, and the differentiation of OI from child abuse, coming to a conclusion that OI knowledge can be of great importance to forensic pathologists and that the merits of postmortem MSCT should be emphasized in forensic pathologic examinations.


Assuntos
Tomografia Computadorizada Multidetectores/métodos , Osteogênese Imperfeita/diagnóstico , Autopsia , Criança , Morte , Evolução Fatal , Feminino , Feto , Patologia Legal , Humanos , Recém-Nascido , Osteogênese Imperfeita/fisiopatologia , Gravidez , Costelas , Crânio/patologia
13.
BMC Genomics ; 16: 398, 2015 May 21.
Artigo em Inglês | MEDLINE | ID: mdl-25994052

RESUMO

BACKGROUND: Tapping panel dryness (TPD) involves in the partial or complete cessation of latex flow thus seriously affect latex production in rubber tree (Hevea brasiliensis). Numerous studies have been conducted to define its origin and nature, but the molecular nature and mechanism of TPD occurrence remains unknown. This study is committed to de novo sequencing and comparative analysis of the transcriptomes of healthy (H) and TPD-affected (T) rubber trees to identify the genes and pathways related to the TPD. RESULTS: Total raw reads of 34,632,012 and 35,913,020 bp were obtained from H and T library, respectively using Illumina Hiseq 2000 sequencing technology. De novo assemblies yielded 141,456 and 169,285 contigs, and 96,070 and 112,243 unigenes from H and T library, respectively. Among 73597 genes, 22577 genes were identified as differential expressed genes between H and T library via comparative transcript profiling. A majority of genes involved in natural rubber biosynthesis and jasmonate synthesis with most potential relevance in TPD occurrence were found to be differentially expressed. CONCLUSIONS: In TPD-affected trees, the expression of most genes related to the latex biosynthesis and jasmonate synthesis was severely inhibited and is probably the direct cause of the TPD. These new de novo transcriptome data sets provide a significant resource for the discovery of genes related to TPD and improve our understanding of the occurrence and maintainace of TPD.


Assuntos
Ciclopentanos/metabolismo , Perfilação da Expressão Gênica/métodos , Hevea/metabolismo , Oxilipinas/metabolismo , Borracha/metabolismo , Análise de Sequência de RNA/métodos , Regulação da Expressão Gênica de Plantas , Hevea/genética , Doenças das Plantas/genética , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , RNA Mensageiro/análise , RNA de Plantas/análise
14.
Inorg Chem ; 54(5): 2088-90, 2015 Mar 02.
Artigo em Inglês | MEDLINE | ID: mdl-25689139

RESUMO

A Cu(+)-CP based on the tetranuclear unit {[(HSQPA)2Cu4(bipy)4]·2H2O}n·2nH2O has been constructed through Cu(2+) salt, 2-(sulfonylquinlium-8-yloxy)phthalic acid (H3SQPA), and 4,4'-bipyridine (bipy). This Cu(+)-CP combined with 2,2,6,6-tetramethylpiperidine-1-oxyl as the cocatalyst is an effective catalyst for aerobic oxidation of alcohols and the synthesis of benzoxazoles and can be recycled at least four times without losing its catalytic activity.


Assuntos
Álcoois/química , Benzoxazóis/síntese química , Cobre/química , Óxidos N-Cíclicos/química , Compostos Organometálicos/química , Polímeros/química , Benzoxazóis/química , Catálise , Modelos Moleculares , Estrutura Molecular , Compostos Organometálicos/síntese química , Oxirredução
15.
Environ Sci Technol ; 49(24): 14213-20, 2015 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-26580982

RESUMO

Hollow fiber supported liquid membrane (HFSLM) extraction was coupled with ICP-MS for speciation analysis of labile Ag(I) and total Ag(I) in dispersions of silver nanoparticles (AgNPs) and environmental waters. Ag(I) in aqueous samples was extracted into the HFSLM of 5%(m/v) tri-n-octylphosphine oxide in n-undecane, and stripped in the acceptor of 10 mM Na2S2O3 and 1 mM Cu(NO3)2 prepared in 5 mM NaH2PO4-Na2HPO4 buffer (pH 7.5). Negligible depletion and exhaustive extraction were conducted under static and 250 rpm shaking to extract the labile Ag(I) and total Ag(I), respectively. The extraction equilibration was reached in 8 h for both extraction modes. The extraction efficiency and detection limit were (2.97 ± 0.25)% and 0.1 µg/L for labile Ag(I), and (82.3 ± 2.0)% and 0.5 µg/L for total Ag(I) detection, respectively. The proposed method was applied to determine labile Ag(I) and total Ag(I) in different sized AgNP dispersions and real environmental waters, with spiked recoveries of total Ag(I) in the range of 74.0-98.1%. With the capability of distinguishing labile and total Ag(I), our method offers a new approach for evaluating the bioavailability and understanding the fate and toxicity of AgNPs in aquatic systems.


Assuntos
Extração Líquido-Líquido/métodos , Nanopartículas Metálicas/análise , Prata/análise , Poluentes Químicos da Água/análise , China , Limite de Detecção , Extração Líquido-Líquido/instrumentação , Espectrometria de Massas/métodos , Membranas Artificiais , Nanopartículas Metálicas/química , Compostos Organofosforados/química , Tamanho da Partícula
16.
Macromol Rapid Commun ; 36(9): 852-7, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-25823716

RESUMO

A novel and robust route for the synthesis of a new amphiphilic brush copolymer, poly(glycidyl methacrylate)-graft-polyethylene glycol (PGMA-g-PEG), with high grafting densities of 97%-98% through a "grafting onto" method via carbon dioxide chemistry is reported. PGMA-g-PEG can self-assemble and form stable spherical core-shell micelles in aqueous solution. Besides, the obtained PGMA-g-PEG polymer contains hydroxyurethane structures as the junction sites between the PGMA backbone and PEG side chain, which can be used for further modification.


Assuntos
Dióxido de Carbono/química , Polietilenoglicóis/química , Ácidos Polimetacrílicos/química
17.
Sichuan Da Xue Xue Bao Yi Xue Ban ; 46(6): 837-41, 2015 Nov.
Artigo em Zh | MEDLINE | ID: mdl-26867317

RESUMO

OBJECTIVE: To determine the physicochemical properties of iRGD conjugated doxorubicin loaded liposome (iRGD-LP-DOX), and its effect on targeting and inhibiting growth of A549 cells. METHODS: Liposomes were observed under a transmission electron microscope. Release of doxorubicin from iRGD-LP-DOX was detected by the dialysis bag method. The efficiency of cellular uptake and tumor spheroids penetration on A549 cells in vitro was determined. The anti-proliferation efficiency of iRGD-LP-DOX was evaluated by MTT assay using IC50 (50% inhibition concentration). RESULTS: iRGD-LP-DOX was spherical in a uniform size. Free DOX was released by 100% in 5 h, while LP-DOX and iRGD-LP-DOX were released by about 40% in 48 h. A higher level of iRGD-LP-DOX uptaken by A549 was found compared with that of LP-DOX (P<0.01). Higher fluorescence intensity was detected with iRGD-LP-DOX than with LP-DOX in tumor spheroid. The MTT assay confirmed strong inhibitory effect of iRGD-LP-DOX (P<0.01). CONCLUSION: iRGD can enhance uptake of liposomes by A549 cells and inhibit the proliferation of tumor cells.


Assuntos
Antineoplásicos/química , Doxorrubicina/química , Lipossomos/química , Oligopeptídeos/química , Linhagem Celular Tumoral , Humanos
18.
Sichuan Da Xue Xue Bao Yi Xue Ban ; 46(4): 568-72, 2015 Jul.
Artigo em Zh | MEDLINE | ID: mdl-26480660

RESUMO

OBJECTIVE: To study microbial diversity of peri-implantitis subgingival with high-throughput sequencing, and investigate microbiological etiology of peri-implantitis. METHODS: Subgingival plaques were sampled from the patients with peri-implantitis (D group) and non-peri-implantitis subjects (N group). The microbiological diversity of the subgingival plaques was detected by sequencing V4 region of 16S rRNA with Illumina Miseq platform. The diversity of the community structure was analyzed using Mothur software. RESULTS: A total of 156 507 gene sequences were detected in nine samples and 4 402 operational taxonomic units (OTUs) were found. Selenomonas, Pseudomonas, and Fusobacterium were dominant bacteria in D group, while Fusobacterium, Veillonella and Streptococcus were dominant bacteria in N group. Differences between peri-implantitis and non-peri-implantitis bacterial communities were observed at all phylogenetic levels by LEfSe, which was also found in PcoA test. CONCLUSION: The occurrence of peri-implantitis is not only related to periodontitis pathogenic microbe, but also related with the changes of oral microbial community structure. Treponema, Herbaspirillum, Butyricimonas and Phaeobacte may be closely related to the occurrence and development of peri-implantitis.


Assuntos
Bactérias/classificação , Placa Dentária/microbiologia , Peri-Implantite/microbiologia , DNA Bacteriano/genética , Fusobacterium , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Periodontite , Filogenia , Pseudomonas , RNA Ribossômico 16S/genética , Selenomonas , Análise de Sequência de DNA , Streptococcus , Treponema
19.
Soft Matter ; 10(28): 5201-11, 2014 Jul 28.
Artigo em Inglês | MEDLINE | ID: mdl-24916798

RESUMO

The effect of temperature on the micellar morphology of two polystyrene-b-poly(N-isopropylacrylamide) (PS-b-PNIPAM) diblock copolymers in an aqueous solution was investigated by dynamic light scattering (DLS) and transmission electron microscopy (TEM). At 25 °C, a mixture of vesicles and spheres are observed for the micelles of PS65-b-PNIPAM108, while PS65-b-PNIPAM360 exhibits mixed cylindrical and spherical micellar morphology. Upon increasing the temperature, the micellar morphology becomes spherical for PS65-b-PNIPAM108 at 60 °C and for PS65-b-PNIPAM360 at 40 °C. Such vesicle-to-sphere and cylinder-to-sphere transitions of micellar morphology are reversible when the micellar solutions are cooled back to 25 °C. However, these temperature-induced morphological transitions of the PS-b-PNIPAM micelles are contrary to the theoretical prediction. Qualitative analysis of the free energy shows that vesicular or cylindrical micelles tend to form at higher temperatures if only the overall volume change of the PNIPAM block is considered. The contradiction between the experimental results and theoretical prediction is interpreted in terms of the local deformability of the PNIPAM chains. At elevated temperatures, the collapsed PNIPAM globules are less deformable and must occupy larger areas at the micellar interface, although the overall volume is smaller at higher temperatures. This will lead to a larger repulsion between the PNIPAM globules and a remarkable increase in the free energy of the corona; thus, the formation of vesicles or cylinders at higher temperatures is prohibited.


Assuntos
Resinas Acrílicas/química , Temperatura Alta , Micelas , Poliestirenos/química , Resinas Acrílicas/síntese química , Poliestirenos/síntese química , Soluções/química , Água/química
20.
Front Cell Infect Microbiol ; 14: 1361206, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38800834

RESUMO

Introduction: Alveolar cleft (AC) is a common congenital defect in people with cleft lip and palate (CLP). Alveolar bone grafting (ABG) is typically performed during adolescence, resulting in the fissure remaining in the mouth for a longer length of time. Patients with AC have a greater rate of oral diseases such as dental caries than the normal population, and the precise characteristics of the bacterial alterations caused by AC are unknown. Methods: We recruited a total of 87 subjects and collected dental plaque samples from AC adolescents (AAP), post-operative ABG adolescents (PAP), healthy control adolescents (CAP), AC young adults (AYP), post-operative ABG young adults (PYP), and healthy control young adults (CYP). The sequencing of 16S rRNA genes was performed. Results: The microbial composition of plaque from alveolar cleft patients differed significantly from age-matched healthy controls. Linear discriminant analysis effect size (LEfSe) analysis revealed that AAP was enriched for Neisseria, Haemophilus, Fusobacterium, Rhodococcus, Aggregatibacter, Gemella, and Porphyromonas, whereas AYP was enriched for Capnocytophaga, Rhodococcus, and Actinomyces-f0332. There were phenotypic differences in facultatively anaerobic, Gram-negative, Gram-positive, and oxidative stress tolerance between the AYP group with longer alveolar cleft and the healthy control group according to Bugbase phenotypic predictions. Alveolar bone grafting did not alter the functional phenotype of alveolar cleft patients but reduced the number of differential genera between alveolar cleft patients and healthy controls at both ages. Conclusions: Our study systematically characterized the supragingival plaque microbiota of alveolar cleft patients, post-alveolar bone grafting patients, and matched healthy controls in two ages to gain a better understanding of plaque ecology and microbiology associated with alveolar clefts.


Assuntos
Bactérias , Fenda Labial , Fissura Palatina , Placa Dentária , Microbiota , RNA Ribossômico 16S , Humanos , Placa Dentária/microbiologia , Fissura Palatina/microbiologia , Adolescente , Microbiota/genética , RNA Ribossômico 16S/genética , Feminino , Masculino , Fenda Labial/microbiologia , Adulto Jovem , Bactérias/classificação , Bactérias/genética , Bactérias/isolamento & purificação , Enxerto de Osso Alveolar , Adulto
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