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1.
Anal Chem ; 96(28): 11595-11602, 2024 07 16.
Artículo en Inglés | MEDLINE | ID: mdl-38950152

RESUMEN

Timely diagnosis, monitoring, and management of chronic wounds play crucial roles in improving patients' quality of life, but clinical evaluation of chronic wounds is still ambiguous and relies heavily on the experience of clinician, resulting in increased social and financial burden and delay of optimal treatment. During the different stages of the healing process, specific and dynamic changes of pH values in the wound exudate can be used as biomarkers to reflect the wound status. Herein, a pH-responsive agent with well-behaved photoacoustic (PA) properties, nitrazine yellow (NY), was incorporated in poly(vinyl alcohol)/sucrose (PVA/Suc) hydrogel to construct a wearable pH-sensing patch (PVA/Suc/NY hydrogel) for monitoring of pH values during chronic wound healing. According to Rosencwaig-Gersho theory and the combination of 3D printing technology, the PA chamber volume and chopping frequency were systematically optimized to improve the sensitivity of the PA analytical system. The prepared PVA/Suc/NY hydrogel patch had excellent mechanical properties and flexibility and could maintain conformal contact with skin. Moreover, combined with the miniaturized PA analytical device, it had the potential to detect pH values (5.0-9.0) free from the color interference of blood and therapeutic drugs, which provides a valuable strategy for wound pH value monitoring by PA quantitation. This strategy of combining the wearable hydrogel patch with portable PA analysis offers broad new prospects for the treatment and management of chronic wounds due to its features of simple operation, time savings, and anti-interference.


Asunto(s)
Hidrogeles , Técnicas Fotoacústicas , Dispositivos Electrónicos Vestibles , Concentración de Iones de Hidrógeno , Hidrogeles/química , Animales , Cicatrización de Heridas/efectos de los fármacos , Alcohol Polivinílico/química , Humanos
2.
J Prosthet Dent ; 2024 Feb 19.
Artículo en Inglés | MEDLINE | ID: mdl-38378312

RESUMEN

A digital approach to fabricating a custom holder to attach a mandibular sensor of an optical jaw motion tracking system is described. Typically, jaw motion tracking systems come with standard holders. However, additional chairside time is still required to adapt the holder's arm to the individual arch and securely attach the holder to the mandibular teeth. Moreover, the placement of the standard holder is problematic in patients with a deep vertical overlap or with short clinical crowns. This technique offers a digital approach to designing and fabricating a custom holder in situations where standard holders cannot be efficiently attached. The custom holder is designed to accommodate the available space without interfering with the occlusion, thereby minimizing the time needed to attach the holder and optimizing the workflow for clinical jaw motion tracking.

3.
Pharm Res ; 40(12): 3043-3058, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37914843

RESUMEN

PURPOSE: This study aimed to prepare a stable irinotecan liposome (CPT-11 liposome) and evaluate its antitumor efficacy in a range of tumor models. METHODS: CPT-11 liposome was prepared with a Z-average particle size of 110 ~ 120 nm and high entrapment efficiency (> 95%) and had a good stability within 18 months. Then the antitumor efficacy was studied in human colon (Ls-174t), gastric (NCI-N87), pancreatic (BxPC-3) and small cell lung (NCI-H526) cancer xenograft models. The toxicity of high-dose CPT-11 liposome was also evaluated in Beagle dogs. RESULTS: The results showed that the anti-tumor effects of CPT-11 liposome were markedly superior (at least 10 times higher) to those of the CPT-11 injection group in all four xenograft models. The tissue distribution test in the Ls-174t model further demonstrated that the CPT-11 liposome could alter the plasma and tissue distribution of CPT-11, increase the exposure level of its active metabolite SN-38 in tumor, and ultimately improve antitumor efficiency. Meanwhile, CPT-11 liposome showed a much less toxicity than CPT-11 injection in beagle dogs. CONCLUSIONS: Overall, the CPT-11 liposome may be developed as a new clinical alternative for the cancer patients.


Asunto(s)
Antineoplásicos Fitogénicos , Neoplasias , Humanos , Animales , Perros , Irinotecán , Liposomas , Camptotecina/farmacología , Camptotecina/uso terapéutico , Modelos Animales de Enfermedad , Antineoplásicos Fitogénicos/uso terapéutico
4.
Sichuan Da Xue Xue Bao Yi Xue Ban ; 54(1): 97-101, 2023 Jan.
Artículo en Zh | MEDLINE | ID: mdl-36647650

RESUMEN

Objective: To analyze the influencing factors of dentition defect in people with type 2 diabetes mellitus (T2DM) and periodontitis and to provide evidence-based support for improving the oral health and quality of life of T2DM patients. Methods: A total of 169 patients with T2DM and periodontitis were selected by convenience sampling. According to the number of remaining teeth, the subjects were divided into two groups, group A (number of remaining teeth in the mouth≥20, n=115) and group B (the number of remaining teeth in the mouth<20, n=54). Questionnaire surveys, systemic and oral examinations, and laboratory blood tests were performed. Systematic influencing factors of dentition defect in people with T2DM and periodontitis were analyzed with logistic regression. Results: Compared with patients in group A, patients in group B had higher findings in age, systolic blood pressure (SBP), prevalence of coronary heart disease and hyperlipidemia, glycosylated hemoglobin (HbA1c), periodontal probing depth (PD), and clinical attachment loss (CAL). Furthermore, their behaviors and awareness of oral health were not as good as those of patients in group A. Logistic regression showed that age, HbA1c, and SBP were independent risk factors for the number of remaining teeth in the mouth <20 among T2DM patients with periodontitis ( P<0.05). Conclusion: Increasing age, lower HbA1c, and increased SBP are the most important influencing factors for the number of remaining teeth in the mouth <20 in T2DM patients with periodontitis. Clinical practitioners should give more attention to the general health status of the patients and strengthen health education, thereby improving patients' quality.


Asunto(s)
Diabetes Mellitus Tipo 2 , Periodontitis , Humanos , Diabetes Mellitus Tipo 2/complicaciones , Hemoglobina Glucada , Dentición , Calidad de Vida , Periodontitis/complicaciones
5.
BMC Oral Health ; 22(1): 118, 2022 04 09.
Artículo en Inglés | MEDLINE | ID: mdl-35397550

RESUMEN

BACKGROUND: Periodontitis is a complex infectious disease with various causes and contributing factors. The aim of this study was to identify key genes, microRNAs (miRNAs) and transcription factors (TFs) and construct a miRNA-mRNA-TF regulatory networks to investigate the underlying molecular mechanism in periodontitis. METHODS: The GSE54710 miRNA microarray dataset and the gene expression microarray dataset GSE16134 were downloaded from the Gene Expression Omnibus database. The differentially expressed miRNAs (DEMis) and mRNAs (DEMs) were screened using the "limma" package in R. The intersection of the target genes of candidate DEMis and DEMs were considered significant DEMs in the regulatory network. Next, Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment analyses were conducted. Subsequently, DEMs were uploaded to the STRING database, a protein-protein interaction (PPI) network was established, and the cytoHubba and MCODE plugins were used to screen out key hub mRNAs and significant modules. Ultimately, to investigate the regulatory network underlying periodontitis, a global triple network including miRNAs, mRNAs, and TFs was constructed using Cytoscape software. RESULTS: 8 DEMis and 121 DEMs were found between the periodontal and control groups. GO analysis showed that mRNAs were most significantly enriched in positive regulation of the cell cycle, and KEGG pathway analysis showed that mRNAs in the regulatory network were mainly involved in the IL-17 signalling pathway. A PPI network was constructed including 81 nodes and 414 edges. Furthermore, 12 hub genes ranked by the top 10% genes with high degree connectivity and five TFs, including SRF, CNOT4, SIX6, SRRM3, NELFA, and ONECUT3, were identified and might play crucial roles in the molecular pathogenesis of periodontitis. Additionally, a miRNA-mRNA-TF coregulatory network was established. CONCLUSION: In this study, we performed an integrated analysis based on public databases to identify specific TFs, miRNAs, and mRNAs that may play a pivotal role in periodontitis. On this basis, a TF-miRNA-mRNA network was established to provide a comprehensive perspective of the regulatory mechanism networks of periodontitis.


Asunto(s)
MicroARNs , Periodontitis , Biología Computacional , Perfilación de la Expresión Génica , Regulación Neoplásica de la Expresión Génica , Redes Reguladoras de Genes/genética , Humanos , MicroARNs/genética , MicroARNs/metabolismo , Periodontitis/genética , ARN Mensajero/genética , ARN Mensajero/metabolismo
6.
BMC Oral Health ; 21(1): 299, 2021 06 12.
Artículo en Inglés | MEDLINE | ID: mdl-34118920

RESUMEN

BACKGROUND: Granulocyte colony-stimulating factor (G-CSF) is an important immune factor that mediates bone metabolism by regulating the functions of osteoclasts and osteoblasts. Bone loss is a serious and progressive result of periodontitis. However, the mechanisms underlying the effects of G-CSF on periodontal inflammation have yet not been completely elucidated. Here, we examined whether an anti-G-CSF antibody could inhibit bone resorption in a model of experimental periodontitis and investigated the local expression of G-CSF in periodontal tissues. METHODS: Experimental periodontitis was induced in mice using ligatures. The levels of G-CSF in serum and bone marrow were measured; immunofluorescence was then performed to analyze the localization and expression of G-CSF in periodontal tissues. Mice with periodontitis were administered anti-G-CSF antibody by tail vein injection to assess the inhibition of bone resorption. Three-dimensional reconstruction was performed to measure bone destruction-related parameters via micro-computed tomography analysis. Immunofluorescence staining was used to investigate the presence of osteocalcin-positive osteoblasts; tartrate-resistant acid phosphatase (TRAP) staining was used to observe osteoclast activity in alveolar bone. RESULTS: The level of G-CSF in serum was significantly elevated in mice with periodontitis. Immunofluorescence analyses showed that G-CSF was mostly expressed in the cell membrane of gingival epithelial cells; this expression was enhanced in the periodontitis group. Additionally, systemic administration of anti-G-CSF antibody significantly inhibited alveolar bone resorption, as evidenced by improvements in bone volume/total volume, bone surface area/bone volume, trabecular thickness, trabecular spacing, and trabecular pattern factor values. Immunofluorescence analysis revealed an enhanced number of osteocalcin-positive osteoblasts, while TRAP staining revealed reduction of osteoclast activity. CONCLUSIONS: G-CSF expression levels were significantly up-regulated in the serum and gingival epithelial cells. Together, anti-G-CSF antibody administration could alleviates alveolar bone resorption, suggesting that G-CSF may be one of the essential immune factors that mediate the bone loss in periodontitis.


Asunto(s)
Pérdida de Hueso Alveolar , Resorción Ósea , Periodontitis , Pérdida de Hueso Alveolar/diagnóstico por imagen , Pérdida de Hueso Alveolar/tratamiento farmacológico , Pérdida de Hueso Alveolar/prevención & control , Animales , Factor Estimulante de Colonias de Granulocitos/uso terapéutico , Ratones , Osteoclastos , Periodontitis/tratamiento farmacológico , Microtomografía por Rayos X
7.
Appl Environ Microbiol ; 86(8)2020 04 01.
Artículo en Inglés | MEDLINE | ID: mdl-32033954

RESUMEN

Cytophaga hutchinsonii cells can bind to the surface of insoluble cellulose and degrade it by utilizing a novel cell contact-dependent mechanism, in which the outer membrane proteins may play important roles. In this study, the deletion of a gene locus, chu_1165, which encodes a hypothetical protein with 32% identity with TlpB, a disulfide oxidoreductase in Flavobacterium psychrophilum, caused a complete cellulolytic defect in C. hutchinsonii Further study showed that cells of the Δ1165 strain could not bind to cellulose, and the levels of many outer membrane proteins that can bind to cellulose were significantly decreased. The N-terminal region of CHU_1165 is anchored to the cytoplasmic membrane with five predicted transmembrane helices, and the C-terminal region is predicted to stretch to the periplasm and has a similar thioredoxin (Trx) fold containing a Cys-X-X-Cys motif that is conserved in disulfide oxidoreductases. Recombinant CHU_1165His containing the Cys-X-X-Cys motif was able to reduce the disulfide bonds of insulin in vitro Site-directed mutation showed that the cysteines in the Cys-X-X-Cys motif and at residues 106 and 108 were indispensable for the function of CHU_1165. Western blotting showed that CHU_1165 was in an oxidized state in vivo, suggesting that it may act as an oxidase to catalyze disulfide bond formation. However, many of the decreased outer membrane proteins that were essential for cellulose degradation contained no or one cysteine, and mutation of the cysteine in these proteins did not affect cellulose degradation, indicating that CHU_1165 may have an indirect or pleiotropic effect on the function of these outer membrane proteins.IMPORTANCECytophaga hutchinsonii can rapidly digest cellulose in a contact-dependent manner, in which the outer membrane proteins may play important roles. In this study, a hypothetical protein, CHU_1165, characterized as a disulfide oxidoreductase, is essential for cellulose degradation by affecting the cellulose binding ability of many outer membrane proteins in C. hutchinsonii Disulfide oxidoreductases are involved in disulfide bond formation. However, our studies show that many of the decreased outer membrane proteins that were essential for cellulose degradation contained no or one cysteine, and mutation of cysteine did not affect their function, indicating that CHU_1165 did not facilitate the formation of a disulfide bond in these proteins. It may have an indirect or pleiotropic effect on the function of these outer membrane proteins. Our study provides an orientation for exploring the proteins that assist in the appropriate conformation of many outer membrane proteins essential for cellulose degradation, which is important for exploring the novel mechanism of cellulose degradation in C. hutchinsonii.


Asunto(s)
Proteínas de la Membrana Bacteriana Externa/metabolismo , Proteínas Bacterianas/genética , Celulosa/metabolismo , Cytophaga/genética , Oxidorreductasas/genética , Secuencia de Aminoácidos , Proteínas Bacterianas/química , Proteínas Bacterianas/metabolismo , Cytophaga/metabolismo , Oxidorreductasas/química , Oxidorreductasas/metabolismo , Alineación de Secuencia
8.
Molecules ; 25(3)2020 Jan 31.
Artículo en Inglés | MEDLINE | ID: mdl-32023918

RESUMEN

A composite flocculant P(AM-DMDAAC) was synthesized by the copolymerization of acrylamide (AM) and dimethyl diallyl ammonium chloride (DMDAAC). By using microwave (MV) assistance with ammonium persulfate as initiator, the synthesis had a short reaction time and yielded a product with good solubility. Fourier-transform infrared spectroscopy, scanning electron microscopy, and differential thermal analysis-thermogravimetric analysis were employed to determine the structure and morphology of P(AM-DMDAAC). The parameters affecting the intrinsic viscosity of P(AM-DMDAAC), such as MV time, mass ratio of DMDAAC to AM, bath time, reaction temperature, pH value, and the dosages of ammonium persulfate initiator, EDTA, sodium benzoate, and urea were examined. Results showed that the optimum synthesis conditions were MV time of 1.5 min, m(DMDAAC):m(AM) of 4:16, 0.5 wt‱ initiator, 0.4 wt‱ EDTA, 0.3 wt‱ sodium benzoate, 2 wt‱ urea, 4 h bath time, reaction temperature of 40 °C, and pH of 2. The optimal dimethyl phthalate (DMP) removal rate can reach 96.9% by using P(AM-DMDAAC), and the P(AM-DMDAAC) had better flocculation than PAM, PAC, and PFS.


Asunto(s)
Resinas Acrílicas/química , Dimetilaminas/química , Ácidos Ftálicos/química , Sulfato de Amonio/química , Floculación , Concentración de Iones de Hidrógeno , Microscopía Electrónica de Rastreo , Microondas , Solubilidad , Espectroscopía Infrarroja por Transformada de Fourier , Temperatura
9.
J Ind Microbiol Biotechnol ; 46(11): 1479-1490, 2019 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-31321576

RESUMEN

The crystalline region of cellulose is the main barrier to the utilization of crystalline cellulose. Cytophaga hutchinsonii actively digests the crystalline region of cellulose by an unknown mechanism. Transposon mutagenesis was done to identify a novel gene locus chu_1557, which is required for efficient disruption of the crystalline region of cellulose, and the absence of CHU_1557 resulted in decreased glucose assimilation efficiency. The defect of the mutant in the disruption of the crystalline region of cellulose was partially retained by additional glucose or pre-culturing the mutant in a low glucose concentration medium which could improve its glucose absorption efficiency. These results suggested that extracellular glucose has important roles in the disruption of crystalline cellulose by C. hutchinsonii. Further study showed that the expression of an outer membrane protein CHU_3732 was downregulated by the absence of CHU_1557 in a low glucose concentration medium. CHU_3732 was involved in uptake of glucose and its expression was induced by a low concentration of glucose. CHU_3732 was predicted to be a porin, so we inferred that it may work as a glucose transport channel in the outer membrane. Based on these results, we deduced that CHU_1557 played a role in the process of glucose assimilation and its disruption affected the expression of other proteins related to glucose transportation such as CHU_3732, and then affected the cell growth in a low glucose concentration medium and disruption of the crystalline region of cellulose.


Asunto(s)
Celulosa/metabolismo , Cytophaga/metabolismo , Glucosa/metabolismo , Proteínas de la Membrana/metabolismo , Cytophaga/genética , Proteínas de la Membrana/genética , Mutagénesis
10.
Appl Environ Microbiol ; 83(1)2017 01 01.
Artículo en Inglés | MEDLINE | ID: mdl-27742681

RESUMEN

Cytophaga hutchinsonii is a Gram-negative bacterium that can efficiently degrade crystalline cellulose by a unique mechanism different from the free cellulase or cellulosome strategy. In this study, chu_3220, encoding the hypothetical protein CHU_3220 (205 kDa), was identified by insertional mutation and gene deletion as the first gene essential for degradation of the crystalline region but not the amorphous region of cellulose by C. hutchinsonii A chu_3220 deletion mutant was defective in the degradation of crystalline cellulose and increased the degree of crystallinity of Avicel PH101 but could still degrade amorphous cellulose completely. CHU_3220 was found to be located on the outer surface of the outer membrane and could bind to cellulose. It contains 15 PbH1 domains and a C-terminal domain (CHU_C) that was proved to be critical for the localization of CHU_3220 on the cell surface and the function of CHU_3220 in crystalline cellulose degradation. Moreover, the degradation of crystalline cellulose was intact-cell dependent and inhibited by NaN3 Further study showed that chu_3220 was induced by cellulose and that the endoglucanase activity on the cell surface was significantly reduced without chu_3220 Real-time PCR revealed that the transcription of most genes encoding endoglucanases located on the cell surface was decreased in the chu_3220 deletion mutant, indicating that chu_3220 might also play a role in the regulation of the expression of some endoglucanases. IMPORTANCE: Cytophaga hutchinsonii could efficiently degrade crystalline cellulose with a unique mechanism without cellulosomes and free cellulases. It lacks proteins that are thought to play important roles in disruption of the crystalline region of cellulose, including exoglucanases, lytic polysaccharide monooxygenases, expansins, expansin-like proteins, or swollenins, and most of its endoglucanases lack carbohydrate binding modules. The mechanism of the degradation of crystalline cellulose is still unknown. In this study, chu_3220 was identified as the first gene essential for the degradation of the crystalline region but not the amorphous region of cellulose. CHU_3220 is a high-molecular-weight protein located on the outer surface of the outer membrane and could bind to cellulose. We proposed that CHU_3220 might be an essential component of a protein complex on the cell surface in charge of the decrystallization of crystalline cellulose. The degradation of crystalline cellulose by C. hutchinsonii was not only dependent on intact cells but also required the energy supplied by the cells. This was obviously different from other known cellulose depolymerization system. Our study has shed more light on the novel strategy of crystalline cellulose degradation by C. hutchinsonii.


Asunto(s)
Proteínas de la Membrana Bacteriana Externa/genética , Proteínas de la Membrana Bacteriana Externa/metabolismo , Celulosa/metabolismo , Cytophaga/metabolismo , Proteínas de la Membrana Bacteriana Externa/aislamiento & purificación , Celulasa/metabolismo , Celulosa/química , Cristalización , Cytophaga/genética , Eliminación de Gen , Mutagénesis Insercional , Reacción en Cadena en Tiempo Real de la Polimerasa
11.
Cardiology ; 136(4): 215-221, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-27802430

RESUMEN

OBJECTIVES: Recent research has indicated that red blood cell distribution width (RDW) is associated with the prognosis of cardiovascular diseases such as chronic heart failure and coronary heart disease. We aimed to study the predictive value of RDW for bleeding events in patients with nonvalvular atrial fibrillation (NVAF) during the administration of 110 mg of dabigatran twice a day after catheter ablation. METHODS: One hundred and seventy-two NVAF patients who were hospitalized and received catheter ablation in Jiangsu Provincial People's Hospital from January 2014 to January 2015 were enrolled (110 mg of dabigatran was administered orally to outpatients preoperatively twice a day for 3 weeks). The enrolled patients were divided into the high RDW (>12.8%) group (n = 85) and the low RDW (≤12.8%) group (n = 87) according to the median RDW. The activated partial thromboplastin time (APTT) at dabigatran trough concentration was also detected. Patients were followed up for 3 months to observe the occurrence of bleeding events, and the predictive value of RDW as well as APTT for bleeding events was assessed from receiver-operating characteristic (ROC) analyses. RESULTS: In all patients, preoperatively, no bleeding events were observed and the APTT did not exceed twice the normal upper limit. Thirteen cases of bleeding events, all minor bleeding, occurred after a 3-month follow-up: 3 of gingival bleeding, 3 of urinary tract bleeding, 3 conjunctival hemorrhages and 4 subcutaneous hemorrhages. The incidence of bleeding events in the low RDW group was lower than in the high RDW group (3.4 vs. 11.8%, p = 0.039). The areas under the ROC curve for RDW and APTT to predict the occurrence of bleeding events were 0.737 (cutoff point 13.25%; p < 0.05) and 0.558 (p > 0.05), respectively. CONCLUSION: RDW was associated with the occurrence of bleeding events in NVAF patients on dabigatran (110 mg twice a day) after ablation, while also being an independent predictor of bleeding events. RDW had superior predictive value for bleeding events over APTT when APTT did not exceed twice the normal upper limit.


Asunto(s)
Antitrombinas/administración & dosificación , Fibrilación Atrial/sangre , Fibrilación Atrial/terapia , Dabigatrán/administración & dosificación , Índices de Eritrocitos , Hemorragia/inducido químicamente , Adulto , Anciano , Antitrombinas/efectos adversos , Ablación por Catéter/efectos adversos , Dabigatrán/efectos adversos , Femenino , Humanos , Incidencia , Masculino , Persona de Mediana Edad , Tiempo de Tromboplastina Parcial , Valor Predictivo de las Pruebas , Cuidados Preoperatorios/métodos , Curva ROC , Análisis de Regresión , Factores de Riesgo , Índice de Severidad de la Enfermedad
12.
Photochem Photobiol Sci ; 15(2): 181-6, 2016 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-26787048

RESUMEN

A facile method for in situ fabrication of three-dimensional gold nanoparticle micropatterns in a cell-resistant polyethylene glycol hydrogel has been developed by combining photochemical synthesis of gold nanoparticles with photolithography technology. The gold nanoparticle micropatterns were further bio-modified with cell integrated polypeptide NcysBRGD based on a gold-thiol bond to improve cell behaviors. Primary cell tests showed that NcysBRGD can enhance cell adhesion very well on the surface of gold nanoparticle micropatterns.


Asunto(s)
Oro/química , Hidrogel de Polietilenoglicol-Dimetacrilato/química , Nanopartículas del Metal/química , Péptidos/química , Secuencia de Aminoácidos , Materiales Biocompatibles/química , Adhesión Celular , Diseño de Equipo , Células HeLa , Humanos , Nanopartículas del Metal/ultraestructura , Microtecnología , Datos de Secuencia Molecular , Compuestos de Sulfhidrilo/química , Análisis de Matrices Tisulares/instrumentación
13.
Analyst ; 141(10): 2948-54, 2016 05 10.
Artículo en Inglés | MEDLINE | ID: mdl-27049139

RESUMEN

Ru(ii) polypyridyl complexes have been expected as promising therapeutic agents against cancer owing to its DNA photocleavage activity. However, the lack of cell selectivity poses a significant obstacle to their practical application. Herein, the strategy combining cell-specific imaging with photoinduced cell death based on [Ru(phen)2(dppz)](2+) has been developed by incorporating [Ru(phen)2(dppz)](2+) into folate-conjugated liposomes. The cells overexpressing folate receptors could specifically recognize this vehicle and be imaged through the luminescence of [Ru(phen)2(dppz)](2+). Thereafter, the delivered [Ru(phen)2(dppz)](2+) interacted with DNA in cells and led to photoinduced cell death. This work provided a possible alternative for cancer diagnosis and therapy.


Asunto(s)
Ácido Fólico/química , Compuestos Organometálicos/química , Rutenio/química , Células A549 , Muerte Celular , ADN , Células HeLa , Humanos , Liposomas , Luminiscencia , Células MCF-7 , Fototerapia
14.
J Environ Manage ; 180: 238-46, 2016 Sep 15.
Artículo en Inglés | MEDLINE | ID: mdl-27233049

RESUMEN

A comprehensive study was carried out to assess metal contamination in five cities spanning from temperate to tropical environment along the coastal line of China with different hydrographical conditions. At each of the five cities, Artificial Mussels (AM) were deployed together with a native species of mussel at a control site and a polluted site. High levels of Cr, Cu and Hg were found in Qingdao, high level of Cd, Hg and Pb was found in Shanghai, and high level of Zn was found in Dalian. Furthermore, level of Cu contamination in all the five cities was consistently much higher than those reported in similar studies in other countries (e.g., Australia, Portugal, Scotland, Iceland, Korea, South Africa and Bangladesh). Levels of individual metal species in the AM showed a highly significant correlation with that in the native mussels (except for Zn in Mytilus edulis and Cd in Perna viridis), while no significant difference can be found between the regression relationships of metal in the AM and each of the two native mussel species. The results demonstrated that AM can provide a reliable time-integrated estimate of metal concentration in contrasting environments over large biogeographic areas and different hydrographic conditions, and overcome the shortcomings of monitoring metals in water, sediment and the use of biomonitors.


Asunto(s)
Monitoreo del Ambiente/instrumentación , Metales Pesados/metabolismo , Océanos y Mares , Unionidae/metabolismo , Contaminantes Químicos del Agua/metabolismo , Animales , China , Monitoreo del Ambiente/métodos , Resinas Sintéticas/química
15.
Int J Biol Macromol ; 259(Pt 2): 129405, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38219944

RESUMEN

Titanium dioxide-based materials treat wastewater contaminated by organic pollutants. However, the wide band gap and the ease of agglomeration limit its photocatalytic activity. PDA/PEI@TiO2@P-HSM composites were synthesized using PDA/PEI as an interfacial bonding modifier via polymerization reaction. Phase and chemical bonding analysis confirmed the modifiedTiO2 coated P-HSM, which can effectively reduce the band gap and control the agglomeration of titanium dioxide, i.e., suitable to degrade RhB. Under UV irradiation, PDA/PEI @TiO2@P-HSM can remove RhB up to 90 % in 100 min. The photocatalytic degradation process conforms to the Langmuir-Hinshelwood quasi-primary equation. The composite exhibited excellent stability and recycling i.e., a high removal effect, with a removal rate of up to 60 % after seven cycles of reaction.


Asunto(s)
Indoles , Polímeros , Rodaminas , Contaminantes Químicos del Agua , Contaminantes Químicos del Agua/análisis , Rayos Ultravioleta , Titanio , Catálisis
16.
Anal Methods ; 16(31): 5441-5449, 2024 Aug 08.
Artículo en Inglés | MEDLINE | ID: mdl-39041882

RESUMEN

African swine fever (ASF) is a highly contagious and severe hemorrhagic disease caused by the African swine fever virus (ASFV). The continuous spread of ASFV affects the safety of the global meat supply; therefore, the establishment of sensitive and specific detection methods for ASFV has become an important hot spot in food safety. Herein, we developed a flexible magnetoelastic (ME) biosensor based on PDMS/FeSiB/QDs composite films for the detection of ASFV P72 protein. Based on the high luminescence performance of CsPbBr3 quantum dots and the excellent magnetoelastic effect of FeSiB, flexible ME biosensors convert stress signals generated by antibody-antigen-specific binding into optical and electromagnetic signals. The nanostructures covalently linked by quantum dots and PDMS provide biomodification sites for ASFV P72 antibodies, simplifying the functionalization modification process compared to the case of conventional biosensors. The deformation of the PDMS film is amplified, and the conversion of surface stress signals to electrical signals is enhanced by exposing the biosensor to a uniform magnetic field. The experimental results proved that the flexible ME biosensor has a wide linear range of 10 ng mL-1-100 µg mL-1, and the detection limit is as low as 0.079 ng mL-1. Moreover, the flexible ME biosensor also shows good stability, sensitivity and specificity, confirming the potential for early disease screening.


Asunto(s)
Virus de la Fiebre Porcina Africana , Técnicas Biosensibles , Dimetilpolisiloxanos , Puntos Cuánticos , Técnicas Biosensibles/métodos , Virus de la Fiebre Porcina Africana/aislamiento & purificación , Dimetilpolisiloxanos/química , Puntos Cuánticos/química , Animales , Proteínas Virales/química , Porcinos , Elasticidad , Límite de Detección
17.
ACS Sens ; 9(1): 406-414, 2024 01 26.
Artículo en Inglés | MEDLINE | ID: mdl-38183297

RESUMEN

Magnetorheological elastomer thin films (MREFs) exhibit remarkable deformability and an adjustable modulus under magnetic fields, rendering them promising in fields such as robotics, flexible sensors, and biomedical engineering. Here, we fabricated MREF by introducing magnetostrictive particles (MSPs) and evaluated the magneto-mechanical coupling effect on the enhancement of sensitivity. The saturation magnetization (Ms) in a parallel anisotropic TbDyFe-PDMS MREF was 5.8 emu/g, and the initial tensile modulus was 55% greater than that of an Iso MREF. We propose a nonlinear magnetorheological formula on the magnetostriction effect, incorporating magnetic dipole interactions and the nonlinear prestress of magnetic particles. This formula highlights the complex nonlinear relationship between the external magnetic field (H) and the key parameters that affect the enhanced MR effect of MSPs-MREF, such as saturation magnetization, remanence (Mr), magnetostriction constant (λs) and stress deviator in ferromagnetic particles (Sed) in the magnetic chain structure. Furthermore, we validate the influence of the key parameters of the rectified magnetorheological formula on a nonlinear magneto-mechanical behavior of MSPs-MREF in PDMS-based MSPs-MREF models by using finite-element simulations. Finally, we developed a biosensor based on MSPs-MREF to detect human serum albumin at low concentrations in human urine samples. There is a 4-fold increase in sensitivity, a lower detection of limit (0.442 µg/mL), and a faster response time (15 min) than traditional biosensors, which in the future might provide an effective way of detecting biomolecules of low concentrations.


Asunto(s)
Elastómeros , Robótica , Humanos , Campos Magnéticos , Imanes
18.
Food Chem ; 418: 135869, 2023 Aug 30.
Artículo en Inglés | MEDLINE | ID: mdl-37001351

RESUMEN

The widespread heavy metal pollution endangers human health; hence, accurate on-site detection and quantification of heavy metal content in the surroundings is a vital step in reversing the harmful effect. Herein, an electrochemical sensor based on flexible cerium metal-organic framework@multi-walled carbon nanotubes/carbon cloth (CeMOF@MWCNTs/CC) was constructed for simultaneous on-site detection of Cd2+ and Pb2+ in food and water samples. The rich carboxyl groups of MWCNTs provided abundant sites for the adsorption of Cd2+ and Pb2+, and the mutual conversion of Ce3+ and Ce4+ in CeMOF facilitated the reduction and reoxidation of metal ions. The prepared electrode showed excellent performance in the simultaneous measurement of Cd2+ and Pb2+, with detection limits of 2.2 ppb and 0.64 ppb, respectively. More importantly, the sensing platform has been successfully used to detect simultaneously Cd2+ and Pb2+ in grain and water samples, and the detection results were consistent with the standard methods, showing great potential in environmental monitoring and food safety.


Asunto(s)
Cerio , Estructuras Metalorgánicas , Metales Pesados , Nanotubos de Carbono , Humanos , Cadmio/química , Fibra de Carbono , Plomo , Estructuras Metalorgánicas/química , Metales Pesados/química , Nanotubos de Carbono/química , Agua , Análisis de los Alimentos , Alimentos
19.
Mol Pharm ; 9(11): 2974-85, 2012 Nov 05.
Artículo en Inglés | MEDLINE | ID: mdl-22957964

RESUMEN

A novel anionic PEG derivative with a wheat-like structure, PEG-poly(AGE-Suc), was synthesized. The spikelet part of this polymer consisting of 9.3 pairs of carboxylic acid side chains was conjugated at one end of the PEG chain. The neutral linear PEG(1580) was designed as the stalk part to improve the biocompatibility of the vectors. The obtained polymer PEG-poly(AGE-Suc) was further modified by folate (FA) at the distal end to achieve the cell-specific targeting. It was confirmed that the negatively charged FA-PEG-poly(AGE-Suc) could coat the positively charged PEI 25K/DNA complex and form a ternary complex by electrostatic interaction. The addition of FA-PEG-poly(AGE-Suc) could change the positive charge of PEI 25K/DNA complexes to negative with no influence on the diameter. The ternary complex with the coat of FA-PEG-poly(AGE-Suc) could effectively condense DNA and protect it from degradation by DNase I. The nonspecific interaction between PEI 25K/DNA complexes and blood components was also significantly reduced by the addition of anionic PEG. The ternary complex PEI 25K/DNA/FA-PEG-poly(AGE-Suc) exhibited a 12-fold higher transfection efficiency on 293T cells compared to PEI 25K/DNA in the serum-containing medium. The competitive folate inhibition assay demonstrated that the higher transfection efficiency of PEI 25K/DNA/FA-PEG-poly(AGE-Suc) was attributed to the folate molecule conjugated to the distal end of FA-PEG-poly(AGE-Suc). The ternary complex PEI 25k/DNA/FA-PEG-poly(AGE-Suc) with low side effects and high transfection efficiency may be a novel effective gene delivery system.


Asunto(s)
Proliferación Celular , ADN/administración & dosificación , Técnicas de Transferencia de Gen , Vectores Genéticos/administración & dosificación , Polietilenglicoles/química , Polímeros/química , Unión Competitiva , Células Cultivadas , Eritrocitos/citología , Eritrocitos/metabolismo , Ácido Fólico/metabolismo , Proteínas Fluorescentes Verdes/metabolismo , Humanos , Riñón/citología , Riñón/metabolismo , Tamaño de la Partícula
20.
Bioresour Technol ; 360: 127581, 2022 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-35798169

RESUMEN

The anode biofilm serves as the core dominating the performance of microbial fuel cell (MFC) biosystem. This research provides new insights into hydrolyzed polyacrylamide (HPAM) biotransformation during the formation of anode biofilm. The current density, coulombic efficiency, voltage, power density, volatile fatty acid (VFA) production and total nitrogen (TN) removal enhanced with the thickening of biofilm (1-6 cm), and the maximums achieved 146 mA·m-2, 47.3%, 8.76 V, 1.28 W·m-2, 184 mg·L-1 and 84.6%, respectively. HPAM concentration descended from 508 mg·L-1 to 83.3 mg·L-1 after 60 days. HPAM was metabolized into VFAs, N2, NO2--N and NO3--N, thereby releasing electrons. Laccase and tyrosine/tryptophan protein induced HPAM metabolism and bioelectricity production. The microbial functions involving HPAM biotransformation and bioelectricity generation were clarified. The alternative resource recovery, techno-economic comparison and development direction of MFC biosystem were discussed to achieve the synchronization of HPAM-containing wastewater treatment and bioelectricity generation based on MFC biosystem.


Asunto(s)
Fuentes de Energía Bioeléctrica , Resinas Acrílicas , Biopelículas , Biotransformación , Electricidad , Electrodos , Aguas Residuales
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