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1.
Genome Res ; 29(11): 1805-1815, 2019 11.
Artículo en Inglés | MEDLINE | ID: mdl-31649058

RESUMEN

Hybridization drives rapid speciation by shaping novel genotypic and phenotypic profiles. Genomic incompatibility and transcriptome shock have been observed in hybrids, although this is rarer in animals than in plants. Using the newly sequenced genomes of the blunt snout bream (Megalobrama amblycephala [BSB]) and the topmouth culter (Culter alburnus [TC]), we focused on the sequence variation and gene expression changes in the reciprocal intergeneric hybrid lineages (F1-F3) of BSB × TC. A genome-wide transcriptional analysis identified 145-974 expressed recombinant genes in the successive generations of hybrid fish, suggesting the rapid emergence of allelic variation following hybridization. Some gradual changes of gene expression with additive and dominance effects and various cis and trans regulations were observed from F1 to F3 in the two hybrid lineages. These asymmetric patterns of gene expression represent the alternative strategies for counteracting deleterious effects of the subgenomes and improving adaptability of novel hybrids. Furthermore, we identified positive selection and additive expression patterns in transforming growth factor, beta 1b (tgfb1b), which may account for the morphological variations of the pharyngeal jaw in the two hybrid lineages. Our current findings provide insights into the evolution of vertebrate genomes immediately following hybridization.


Asunto(s)
Alelos , Cyprinidae/genética , Hibridación Genética , Animales , Femenino , Masculino , Polimorfismo Genético , Análisis de Secuencia/métodos , Especificidad de la Especie
2.
Nanotechnology ; 33(24)2022 Mar 23.
Artículo en Inglés | MEDLINE | ID: mdl-35172281

RESUMEN

The use of conventional fabrication methods rapidly developed the performance and notable enhancements of optoelectronic devices. However, it proved challenging to develop and demonstrate stable optoelectronic devices with biodegradability and biocompatibility properties towards sustainable development and extensive applications. This study incorporates a water-soluble Cr-phycoerythrin (Cr-PE) biomaterial to observe its optical and electronic properties effects on the pristine indium gallium zinc oxide (IGZO)-based photodetector. The fabricated photodetector demonstrates an extended absorption detection region, enhanced optoelectronic performance, and switchable function properties. The resulting photocurrent and responsivity of the IGZO/Cr-PE structure have increased by 5.7 and 7.1 times as compared to the pristine IGZO photodetector. It was also observed that the photodetector could operate in UV and UV-visible with enhanced optical properties by effectively adding the water-soluble Cr-PE. Also, the sensing region of IGZO photodetector becomes changeable. It exhibits switchable dual detection by alternatively dripping and removing the Cr-PE on the IGZO layer. Different measurement parameters such as detectivity, repeatability, and sensitivity are highlighted to effectively prove the advantage of including Cr-PE on the photodetector structure. This study contributes to understanding the potential functions in improving optoelectronic devices through an environmental-friendly method.


Asunto(s)
Galio , Indio , Materiales Biocompatibles , Galio/química , Indio/química , Agua , Zinc
3.
Sensors (Basel) ; 19(7)2019 Mar 27.
Artículo en Inglés | MEDLINE | ID: mdl-30934691

RESUMEN

In this research, we developed a miRNA sensor using an electrical double layer (EDL) gated field-effect transistor (FET)-based biosensor with enhanced sensitivity and stability. We conducted an in-depth investigation of the mechanisms that give rise to fluctuations in the electrical signal, affecting the stability and sensitivity of the miRNA sensor. Firstly, surface characteristics were studied by examining the metal electrodes deposited using different metal deposition techniques. The lower surface roughness of the gold electrode improved the electrical current stability. The temperature and viscosity of the sample solution were proven to affect the electrical stability, which was attributed to reducing the effect of Brownian motion. Therefore, by controlling the test conditions, such as temperature and sample viscosity, and the surface characteristics of the metal electrodes, we can enhance the stability of the sensor. Metal electrodes deposited via sputtering and e-beam evaporator yielded the lowest signal fluctuation. When ambient temperature was reduced to 3 °C, the sensor had better noise characteristics compared to room temperature testing. Higher viscosity of samples resulted in lower signal fluctuations. Lastly, surface functionalization was demonstrated to be a critical factor in enhancing the stability and sensitivity. MiRNA sensors with higher surface ratios of immobilized DNA probes performed with higher sensitivity and stability. This study reveals methods to improve the characteristics of EDL FET biosensors to facilitate practical implementation in clinical applications.


Asunto(s)
Técnicas Biosensibles/métodos , MicroARNs/análisis , Transistores Electrónicos , Aptámeros de Nucleótidos/química , Aptámeros de Nucleótidos/metabolismo , Técnicas Biosensibles/instrumentación , ADN de Cadena Simple/química , ADN de Cadena Simple/metabolismo , Conductividad Eléctrica , Electrodos , Oro/química , MicroARNs/metabolismo , Hibridación de Ácido Nucleico , Polímeros/química , Propiedades de Superficie , Temperatura
4.
Artif Organs ; 40(4): E39-50, 2016 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-26582651

RESUMEN

The purpose of this study was to demonstrate the feasibility of whole-tooth regeneration using a tooth germ-like construct. Dental pulp from upper incisors, canines, premolars, and molars were extracted from sexually mature miniature pigs. Pulp tissues were cultured and expanded in vitro to obtain dental pulp stem cells (DPSCs), and cells were differentiated into odontoblasts and osteoblasts. Epithelial cells were isolated from gingival epithelium. The epithelial cells, odontoblasts, and osteoblasts were seeded onto the surface, upper, and lower layers, respectively, of a bioactive scaffold. The lower first and second molar tooth germs were removed bilaterally and the layered cell/scaffold constructs were transplanted to the mandibular alveolar socket of a pig. At 13.5 months postimplantation, seven of eight pigs developed two teeth with crown, root, and pulp structures. Enamel-like tissues, dentin, cementum, odontoblasts, and periodontal tissues were found upon histological inspection. The regenerated tooth expressed dentin matrix protein-1 and osteopontin. All pigs had regenerated molar teeth regardless of the original tooth used to procure the DPSCs. Pigs that had tooth germs removed or who received empty scaffolds did not develop teeth. Although periodontal ligaments were generated, ankylosis was found in some animals. This study revealed that implantation of a tooth germ-like structure generated a complete tooth with a high success rate. The implant location may influence the morphology of the regenerated tooth.


Asunto(s)
Regeneración/fisiología , Andamios del Tejido , Germen Dentario/fisiología , Diente/fisiología , Animales , Porcinos , Porcinos Enanos , Ingeniería de Tejidos , Diente/citología , Germen Dentario/citología
5.
Int J Mol Sci ; 16(7): 15104-17, 2015 Jul 03.
Artículo en Inglés | MEDLINE | ID: mdl-26151845

RESUMEN

BubR1 is a critical component of spindle assembly checkpoint, ensuring proper chromatin segregation during mitosis. Recent studies showed that BubR1 was overexpressed in many cancer cells, including oral squamous cell carcinomas (OSCC). However, the effect of BubR1 on metastasis of OSCC remains unclear. This study aimed to unravel the role of BubR1 in the progression of OSCC and confirm the expression of BubR1 in a panel of malignant OSCC cell lines with different invasive abilities. The results of quantitative real-time PCR showed that the mRNA level of BubR1 was markedly increased in four OSCC cell lines, Ca9-22, HSC3, SCC9 and Cal-27 cells, compared to two normal cells, normal human oral keratinocytes (HOK) and human gingival fibroblasts (HGF). Moreover, the expression of BubR1 in these four OSCC cell lines was positively correlated with their motility. Immunofluorescence revealed that BubR1 was mostly localized in the cytosol of human gingival carcinoma Ca9-22 cells. BubR1 knockdown significantly decreased cellular invasion but slightly affect cellular proliferation on both Ca9-22 and Cal-27 cells. Consistently, the activities of metastasis-associated metalloproteinases MMP-2 and MMP-9 were attenuated in BubR1 knockdown Ca9-22 cells, suggesting the role of BubR1 in promotion of OSCC migration. Our present study defines an alternative pathway in promoting metastasis of OSCC cells, and the expression of BubR1 could be a prognostic index in OSCC patients.


Asunto(s)
Carcinoma de Células Escamosas/metabolismo , Movimiento Celular , Metaloproteinasa 2 de la Matriz/metabolismo , Neoplasias de la Boca/metabolismo , Proteínas Serina-Treonina Quinasas/metabolismo , Línea Celular Tumoral , Proliferación Celular , Fibroblastos/metabolismo , Fibroblastos/fisiología , Humanos , Queratinocitos/metabolismo , Queratinocitos/fisiología , Metaloproteinasa 2 de la Matriz/genética , Metaloproteinasa 9 de la Matriz/genética , Metaloproteinasa 9 de la Matriz/metabolismo , Proteínas Serina-Treonina Quinasas/genética
6.
Molecules ; 19(11): 18721-32, 2014 Nov 14.
Artículo en Inglés | MEDLINE | ID: mdl-25405289

RESUMEN

Many red algae-derived natural products are known to have anticancer effects. The biological functions of the red alga Solieria robusta from the Karachi coast (Pakistan) remain unclear. Here, we prepared a methanolic extracts of S. robusta (MESR) to examine its possible anti-oral cancer effects and the corresponding mechanism of action. Cell viability of MESR-incubated oral cancer Ca9-22 cells was dose-responsively decreased (p<0.001). According to a propidium iodide (PI)-based assay the cell cycle distribution was dramatically changed, especially for subG1 accumulation. Annexin V/PI assay of apoptosis using flow cytometry also showed that MESR-incubated Ca9-22 cells were dose-responsively increased (p<0.001). For evaluation of oxidative stress in MESR-incubated Ca9-22 cells, we found that reactive oxygen species (ROS) were overexpressed dose- and time-responsively and mitochondrial depolarization was also increased (p<0.001). Taken together, MESR showed inhibitory effects on oral cancer proliferation coupled with apoptosis and oxidative stress.


Asunto(s)
Antineoplásicos Fitogénicos , Apoptosis/efectos de los fármacos , Proliferación Celular/efectos de los fármacos , Neoplasias Gingivales/tratamiento farmacológico , Estrés Oxidativo/efectos de los fármacos , Extractos Vegetales , Rhodophyta/química , Antineoplásicos Fitogénicos/química , Antineoplásicos Fitogénicos/farmacología , Línea Celular Tumoral , Relación Dosis-Respuesta a Droga , Neoplasias Gingivales/metabolismo , Neoplasias Gingivales/patología , Humanos , Metanol/química , Extractos Vegetales/química , Extractos Vegetales/farmacología , Especies Reactivas de Oxígeno/metabolismo
7.
J Hazard Mater ; 467: 133631, 2024 Apr 05.
Artículo en Inglés | MEDLINE | ID: mdl-38335610

RESUMEN

Ubiquitous pollution due to microplastics through the food chain is a major cause of various deleterious effects on the human health. The aim of this study was to determine the existence of microplastics and the internal mechanism of microplastics as accelerators of cholelithiasis. Gallstones were collected from 16 patients after cholecystectomy, and microplastics in the gallstones were detected through laser direct infrared and pyrolysis gas chromatographymass spectrometry examinations. Mice model of gallstone were constructed with or without different diameters of microplastic (0.5, 5 and 50 µm). The affinity between microplastic and cholesterol or bilirubin was tested by co-culturing and qualified using molecular dynamics simulations. Finally, altered gut microbiota among the groups were identified using 16 s rRNA sequencing. The presence of microplastics in the gallstones of all the patients were confirmed. Microplastic content was significantly higher in younger chololithiasis patients (age<50 years). Mice fed a high-cholesterol diet with microplastic drinks showed more severe chololithiasis. In terms of the mechanism, microplastics showed a higher affinity for cholesterol than for bilirubin. Significant alterations in the gut microbiota have also been identified after microplastic intake in mice. Our study revealed the presence of microplastics in human gallstones, showcasing their potential to aggravate chololithiasis by forming large cholesterol-microplastic heteroaggregates and altering the gut microbiota.


Asunto(s)
Cálculos Biliares , Humanos , Animales , Ratones , Persona de Mediana Edad , Microplásticos , Plásticos , Colesterol , Bilirrubina
8.
mSystems ; 9(1): e0116923, 2024 Jan 23.
Artículo en Inglés | MEDLINE | ID: mdl-38108668

RESUMEN

The microbiota plays an important role in both hypertension (HTN) and periodontitis (PD), and PD exacerbates the development of HTN by oral and gut microbiota. Previous studies have focused on exploring the importance of the bacteriome in HTN and PD but overlooked the impact of the virome, which is also a member of the microbiota. We collected 180 samples of subgingival plaques, saliva, and feces from a cohort of healthy subjects (nHTNnPD), subjects with HTN (HTNnPD) or PD (PDnHTN), and subjects with both HTN and PD (HTNPD). We performed metagenomic sequencing to assess the roles of the oral and gut viromes in HTN and PD. The HTNnPD, PDnHTN, and HTNPD groups all showed significantly distinct beta diversity from the nHTNnPD group in saliva. We analyzed alterations in oral and gut viral composition in HTN and/or PD and identified significantly changed viruses in each group. Many viruses across three sites were significantly associated with blood pressure and other clinical parameters. Combined with these clinical associations, we found that Gillianvirus in subgingival plaques was negatively associated with HTN and that Torbevirus in saliva was positively associated with HTN. We found that Pepyhexavirus from subgingival plaques was indicated to be transferred to the gut. We finally evaluated viral-bacterial transkingdom interactions and found that viruses and bacteria may cooperate to affect HTN and PD. Correspondingly, HTN and PD may synergize to improve communications between viruses and bacteria.IMPORTANCEPeriodontitis (PD) and hypertension (HTN) are both highly prevalent worldwide and cause serious adverse outcomes. Increasing studies have shown that PD exacerbates HTN by oral and gut microbiota. Previous studies have focused on exploring the importance of the bacteriome in HTN and PD but overlooked the impact of the virome, even though viruses are common inhabitants in humans. Alterations in oral and gut viral diversity and composition contribute to diseases. The present study, for the first time, profiled the oral and gut viromes in HTN and/or PD. We identified key indicator viruses and their clinical implications in HTN and/or PD. We also investigated interactions between viruses and bacteria. This work improved the overall understanding of the viromes in HTN and PD, providing vital insights into the role of the virome in the development of HTN and PD.


Asunto(s)
Hipertensión , Microbiota , Periodontitis , Virus , Humanos , Viroma , Virus/genética , Microbiota/genética
9.
J Biomed Mater Res B Appl Biomater ; 111(2): 382-391, 2023 02.
Artículo en Inglés | MEDLINE | ID: mdl-36053824

RESUMEN

Calcium sulfate, an injectable and biodegradable bone-void filler, is widely used in orthopedic surgery. Based on clinical experience, bone-defect substitutes can also serve as vehicles for the delivery of drugs, for example, antibiotics, to prevent or to treat infections such as osteomyelitis. However, antibiotic additions change the characteristics of calcium sulfate cement. Moreover, high-dose antibiotics may also be toxic to bony tissues. Accordingly, cefazolin at varying weight ratios was added to calcium sulfate samples and characterized in vitro. The results revealed that cefazolin changed the hydration reaction and prolonged the initial setting times of calcium sulfate bone cement. For the crystalline structure identification, X-ray diffractometer revealed that cefazolin additive resulted in the decrease of peak intensity corresponding to calcium sulfate dihydrate which implying incomplete phase conversion of calcium sulfate hemihydrate. In addition, scanning electron microscope inspection exhibited cefazolin changed the morphology and size of the crystals greatly. A relatively higher amount of cefazolin additive caused a faster degradation and a lower compressive strength of calcium sulfate compared with those of uploaded samples. Furthermore, the extract of cefazolin-impregnated calcium sulfate impaired cell viability, and caused the death of osteoblast-like cells. The results of this study revealed that the cefazolin additives prolonged setting time, impaired mechanical strength, accelerated degradation, and caused cytotoxicity of the calcium sulfate bone-void filler. The aforementioned concerns should be considered during intra-operative applications.


Asunto(s)
Sustitutos de Huesos , Sulfato de Calcio , Sulfato de Calcio/farmacología , Sulfato de Calcio/química , Cefazolina/farmacología , Sustitutos de Huesos/farmacología , Sustitutos de Huesos/química , Fuerza Compresiva , Cementos para Huesos/farmacología , Cementos para Huesos/química , Antibacterianos/farmacología , Antibacterianos/uso terapéutico , Excipientes
10.
ACS Appl Mater Interfaces ; 15(23): 27548-27559, 2023 Jun 14.
Artículo en Inglés | MEDLINE | ID: mdl-37272856

RESUMEN

Bacterial infections are one of the major contributing factors to human mortality, which can cause secondary damage to the injured area, such as leading to inflammation, tissue death, and even personal death. Herein, we developed a novel cyclodextrin (CD)-modified amphiphilic microgel with a 3D network nanostructure that encapsulates hydrophilic indocyanine green (ICG) as a trigger for photothermal therapy (PTT) and hydrophobic N,N'-disubstituted-butyl-N,N'-dinitro-1,4-benzenediamine (BNN6) as a heat-sensitive nitric oxide (NO) donor (CD@I-B) to cope with bacteria-infected wound therapy. This biocompatible microgel showed excellent broad-spectrum antibacterial capability under near-infrared (NIR) laser irradiation, while the photothermal conversion process promotes the deswelling of the microgel and release of NO, which synergistically accelerates wound healing. The therapy strategy by synergizing NO delivery with PTT promoted the formation of neovascularization and collagen fiber as well as the elimination of inflammation cells, thus facilitating wound healing. Our study further demonstrates the fantastic opportunities of applying high-performance microgels to provide all-in-one sites for treating wound sterilization and healing.


Asunto(s)
Microgeles , Óxido Nítrico , Humanos , Terapia Fototérmica , Donantes de Óxido Nítrico , Cicatrización de Heridas , Antibacterianos/farmacología , Antibacterianos/química , Inflamación
11.
Adv Healthc Mater ; 12(20): e2203337, 2023 08.
Artículo en Inglés | MEDLINE | ID: mdl-36972711

RESUMEN

Periodontitis and hypertension often occur as comorbidities, which need to be treated at the same time. To resolve this issue, a controlled-release composite hydrogel approach is proposed with dual antibacterial and anti-inflammatory activities as a resolution to achieve the goal of co-treatment of comorbidities. Specifically, chitosan (CS) with inherent antibacterial properties is cross-linked with antimicrobial peptide (AMP)-modified polyethylene glycol (PEG) to form a dual antibacterial hydrogel (CS-PA). Subsequently, curcumin loaded into biodegradable nanoparticles (CNP) are embedded in the hydrogel exhibiting high encapsulation efficiency and sustained release to achieve long-term anti-inflammatory activities. In a mouse model of periodontitis complicated with hypertension, CS-PA/CNP is applied to gingival sulcus and produced an optimal therapeutic effect on periodontitis and hypertension simultaneously. The therapeutic mechanisms are deeply studied and indicated that CS-PA/CNP exerted excellent immunoregulatory effects by suppressing the accumulation of lymphocytes and myeloid cells and enhanced the antioxidant capacity and thus the anti-inflammatory capacity of macrophages through the glutathione metabolism pathway. In conclusion, CS-PA/CNP has demonstrated its superior therapeutic effects and potential clinical translational value in the co-treatment of periodontitis and hypertension, and also serves as a drug delivery platform to provide combinatorial therapeutic options for periodontitis with complicated pathogenesis.


Asunto(s)
Quitosano , Hipertensión , Nanopartículas , Periodontitis , Animales , Ratones , Hidrogeles/uso terapéutico , Hidrogeles/química , Nanopartículas/uso terapéutico , Nanopartículas/química , Antibacterianos/química , Quitosano/química , Periodontitis/tratamiento farmacológico , Antiinflamatorios/uso terapéutico , Comorbilidad , Hipertensión/tratamiento farmacológico
12.
J Adv Res ; 43: 147-161, 2023 01.
Artículo en Inglés | MEDLINE | ID: mdl-36585105

RESUMEN

INTRODUCTION: Considerable evidence has linked periodontitis (PD) to hypertension (HTN), but the nature behind this connection is unclear. Dysbiosis of oral microbiota leading to PD is known to aggravate different systematic diseases, but the alteration of oral microbiota in HTN and their impacts on blood pressure (BP) remains to be discovered. OBJECTIVES: To characterize the alterations of oral and gut microbiota and their roles in HTN. METHODS: We performed a cross-sectional (95 HTN participants and 39 controls) and a 6-month follow-up study (52 HTN participants and 26 controls) to analyze the roles of oral and gut microbiota in HTN. Saliva, subgingival plaques, and feces were collected for 16S rRNA gene sequencing or metagenomic analysis. C57BL/6J mice were pretreated with antibiotics to deplete gut microbiota, and then transplanted with human saliva by gavage to test the impacts of abnormal oral-gut microbial transmission on HTN. RESULTS: BP in participants with PD was higher than no PD in both cross-sectional and follow-up cohort. Relative abundances of 14 salivary genera, 15 subgingival genera and 10 gut genera significantly altered in HTN and those of 7 salivary genera, 12 subgingival genera and 6 gut genera significantly correlated with BP. Sixteen species under 5 genera were identified as oral-gut transmitters, illustrating the presence of oral-gut microbial transmission in HTN. Veillonella was a frequent oral-gut transmitter stably enriched in HTN participants of both cross-sectional and follow-up cohorts. Saliva from HTN participants increased BP in hypertensive mice. Human saliva-derived Veillonella successfully colonized in mouse gut, more abundantly under HTN condition. CONCLUSIONS: PD and oral microbiota are strongly associated with HTN, likely through oral-gut transmission of microbes. Ectopic colonization of saliva-derived Veillonella in the gut may aggravate HTN. Therefore, precise manipulations of oral microbiota and/or oral-gut microbial transmission may be useful strategies for better prevention and treatment of HTN.


Asunto(s)
Microbioma Gastrointestinal , Hipertensión , Microbiota , Periodontitis , Humanos , Animales , Ratones , Microbioma Gastrointestinal/fisiología , ARN Ribosómico 16S/genética , Estudios Transversales , Estudios de Seguimiento , Ratones Endogámicos C57BL
13.
Artif Organs ; 36(4): 418-28, 2012 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-22145803

RESUMEN

While many different filler materials have been applied in vertebral augmentation procedures, none is perfect in all biomechanical and biological characteristics. To minimize possible shortages, we synthesized a new biodegradable, injectable, and premixed composite made from poly(propylene fumarate) (PPF) and biphasic α-tricalcium phosphate (α-TCP)/hydroxyapatite (HAP) ceramics powder and evaluated the material properties of the compound in vitro. We mixed the PPF cross-linked by N-vinyl pyrrolidinone and biphasic α-TCP/HAP powder in different ratios with benzoyl peroxide as an initiator. The setting time and temperature were recorded, although they could be manipulated by modulating the concentrations of hydroquinone and N,N-dimethyl-p-toluidine. Degradation, cytocompatibility, mechanical properties, and radiopacity were analyzed after the composites were cured by a cylindrical shape. We also compared the study materials with poly(methyl methacrylate) (PMMA) and PPF with pure HAP particles. Results showed that lower temperature during curing process (38-44°C), sufficient initial mechanical compressive fracture strength (61.1±3.7MPa), and gradual degradation were observed in the newly developed bone filler. Radiopacity in Hounsfield units was similar to PMMA as determined by computed tomography scan. Both pH value variation and cytotoxicity were within biological tolerable limits based on the biocompatibility tests. Mixtures with 70% α-TCP/HAP powder were superior to other groups. This study indicated that a composite of PPF and biphasic α-TCP/HAP powder is a promising, premixed, injectable biodegradable filler and that a mixture containing 70% α-TCP/HAP exhibits the best properties.


Asunto(s)
Materiales Biocompatibles/química , Cementos para Huesos/química , Fosfatos de Calcio/química , Cerámica/química , Durapatita/química , Fumaratos/química , Polipropilenos/química , Materiales Biocompatibles/metabolismo , Cementos para Huesos/metabolismo , Fosfatos de Calcio/metabolismo , Línea Celular , Proliferación Celular , Cerámica/metabolismo , Durapatita/metabolismo , Fumaratos/metabolismo , Humanos , Ensayo de Materiales , Polipropilenos/metabolismo , Difracción de Polvo , Difracción de Rayos X
14.
Ann Occup Hyg ; 56(2): 233-41, 2012 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-22104317

RESUMEN

Hexavalent chromium (Cr(6+)) emitted from welding poses serious health risks to workers exposed to welding fumes. In this study, tetramethylsilane (TMS) was added to shielding gas to control hazardous air pollutants produced during stainless steel welding. The silica precursor acted as an oxidation inhibitor when it decomposed in the high-temperature welding arc, limiting Cr(6+) formation. Additionally, a film of amorphous SiO(2) was deposited on fume particles to insulate them from oxidation. Experiments were conducted following the American Welding Society (AWS) method for fume generation and sampling in an AWS fume hood. The results showed that total shielding gas flow rate impacted the effectiveness of the TMS process. Increasing shielding gas flow rate led to increased reductions in Cr(6+) concentration when TMS was used. When 4.2% of a 30-lpm shielding gas flow was used as TMS carrier gas, Cr(6+) concentration in gas metal arc welding (GMAW) fumes was reduced to below the 2006 Occupational Safety and Health Administration standard (5 µg m(-3)) and the efficiency was >90%. The process also increased fume particle size from a mode size of 20 nm under baseline conditions to 180-300 nm when TMS was added in all shielding gas flow rates tested. SiO(2) particles formed in the process scavenged nanosized fume particles through intercoagulation. Transmission electron microscopy imagery provided visual evidence of an amorphous film of SiO(2) on some fume particles along with the presence of amorphous SiO(2) agglomerates. These results demonstrate the ability of vapor phase silica precursors to increase welding fume particle size and minimize chromium oxidation, thereby preventing the formation of hexavalent chromium.


Asunto(s)
Contaminantes Ocupacionales del Aire/análisis , Carcinógenos Ambientales/análisis , Cromo/análisis , Gases/análisis , Soldadura/métodos , Aerosoles/análisis , Humanos , Metales , Exposición Profesional/prevención & control , Tamaño de la Partícula , Equipos de Seguridad , Dióxido de Silicio , Acero Inoxidable
15.
Front Cell Infect Microbiol ; 12: 842845, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35273925

RESUMEN

Increasing evidence suggests that periodontitis, characterized by oral dysbiosis, is a critical player in the progression of multiple systemic diseases in humans. However, there is still a lack of a proper mouse model of periodontitis with the colonization of human periodontitis-associated bacteria. We here established a new mouse periodontitis model by combining ligation of the second molars with application of subgingival plaques from periodontitis patients. Using 16S rRNA gene sequencing and Taxonomic classification, we found that human periodontitis-associated bacteria efficiently colonized in the mouse model and were enriched in both ligature silk and mouse saliva. Furthermore, the well-recognized periodontal pathogens including Porphyromonas gingivalis, Fusobacterium nucleatum, Prevotella intermedia, and Tannerella forsythia were enriched in the new model, but not in ligature-induced periodontitis model or Sham mice. The human periodontitis-associated bacteria potently aggravated mouse periodontitis, as demonstrated by more severe bone resorption and higher expression of inflammatory and osteoclastogenesis genes. In summary, the new mouse periodontitis model paves the way for studying human periodontitis-associated bacteria in oral diseases and systemic diseases.


Asunto(s)
Aggregatibacter actinomycetemcomitans , Periodontitis , Animales , Humanos , Ratones , Periodontitis/microbiología , Porphyromonas gingivalis/genética , Prevotella intermedia/genética , ARN Ribosómico 16S/genética
16.
Chemosphere ; 308(Pt 3): 136333, 2022 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-36087726

RESUMEN

In the past two decades, membrane technology has attracted considerable interest as a viable and promising method for water purification. Emerging organic micropollutants (EOMPs) in wastewater have trace, persistent, highly variable quantities and types, develop hazardous intermediates and are diffusible. These primary issues affect EOMPs polluted wastewater on an industrial scale differently than in a lab, challenging membranes-based EOMP removal. Graphene oxide (GO) promises state-of-the-art membrane synthesis technologies and use in EOMPs removal systems due to its superior physicochemical, mechanical, and electrical qualities and high oxygen content. This critical review highlights the recent advancements in the synthesis of next-generation GO membranes with diverse membrane substrates such as ceramic, polyethersulfone (PES), and polyvinylidene fluoride (PVDF). The EOMPs removal efficiencies of GO membranes in filtration, adsorption (incorporated with metal, nanomaterial in biodegradable polymer and biomimetic membranes), and degradation (in catalytic, photo-Fenton, photocatalytic and electrocatalytic membranes) and corresponding removal mechanisms of different EOMPs are also depicted. GO-assisted water treatment strategies were further assessed by various influencing factors, including applied water flow mode and membrane properties (e.g., permeability, hydrophily, mechanical stability, and fouling). GO additive membranes showed better permeability, hydrophilicity, high water flux, and fouling resistance than pristine membranes. Likewise, degradation combined with filtration is two times more effective than alone, while crossflow mode improves the photocatalytic degradation performance of the system. GO integration in polymer membranes enhances their stability, facilitates photocatalytic processes, and gravity-driven GO membranes enable filtration of pollutants at low pressure, making membrane filtration more inexpensive. However, simultaneous removal of multiple contaminants with contrasting characteristics and variable efficiencies in different systems demands further optimization in GO-mediated membranes. This review concludes with identifying future critical research directions to promote research for determining the GO-assisted OMPs removal membrane technology nexus and maximizing this technique for industrial application.


Asunto(s)
Contaminantes Ambientales , Grafito , Adsorción , Grafito/química , Membranas Artificiales , Oxígeno , Polímeros , Aguas Residuales
17.
Artif Organs ; 35(2): 113-21, 2011 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-21083830

RESUMEN

Growth factors and morphogens secreted by bone marrow mesenchymal stem cells (BMSCs) of bone marrow fluid may promote tooth regeneration. Accordingly, a tissue engineering approach was utilized to develop an economical strategy for obtaining the growth factors and morphogens from BMSCs. Unerupted second molar tooth buds harvested from miniature pigs were cultured in vitro to obtain dental bud cells (DBCs). Bone marrow fluid, which contains BMSCs, was collected from the porcine mandible before operation. DBCs suspended in bone marrow fluid were seeded into a gelatin/chondoitin-6-sulfate/hyaluronan tri-copolymer scaffold (GCHT scaffold). The DBCs/bone marrow fluid/GCHT scaffold was autografted into the original alveolar sockets of the pigs. Radiographic and histological examinations were applied to identify the structure of regenerated tooth at 40 weeks postimplantation. The present results showed that one pig developed a complete tooth with crown, root, pulp, enamel, dentin, odontoblast, cementum, blood vessel, and periodontal ligament in indiscriminate shape. Three animals had an unerupted tooth that expressed dentin matrix protein-1, vascular endothelial growth factor, and osteopontin; and two other pigs also had dental-like structure with dentin tubules. This study reveals that DBCs adding bone marrow fluid and a suitable scaffold can promote the tooth regeneration in autogenic cell transplantation.


Asunto(s)
Regeneración Ósea , Ingeniería de Tejidos/métodos , Diente/citología , Diente/fisiología , Animales , Médula Ósea/metabolismo , Células de la Médula Ósea/citología , Células de la Médula Ósea/metabolismo , Células Cultivadas , Femenino , Masculino , Células Madre Mesenquimatosas/citología , Células Madre Mesenquimatosas/metabolismo , Radiografía , Porcinos , Andamios del Tejido/química , Diente/diagnóstico por imagen , Diente/ultraestructura
18.
Int J Nanomedicine ; 16: 201-211, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33447035

RESUMEN

OBJECTIVE: PEGylated superparamagnetic iron oxide (SPIO) is the most promising alternatives to gadolinium-based contrast agents (GBCAs) in MRI. This paper is to explore the imaging effects of PEGylated SPIO, which is influenced by particle sizes and surface polyethylene glycol (PEG) coating, using as MRI contrast agents at different magnetic field intensities. METHODS: Firstly, nine PEGylated monocrystalline SPIO nanoparticles with different nanocrystal sizes and different molecular weights PEG coating were prepared, and then physical and biological properties were analyzed. Finally, MRI imaging in vivo was performed to observe the imaging performance. RESULTS: Nine PEGylated monocrystalline SPIO nanoparticles have good relaxivities, serum stability, and biosecurity. At the same time, they show different imaging characteristics at different magnetic field intensities. Eight-nanometer SPIO@PEG5k is an effective T 2 contrast agent at 3.0 T (r 2/r 1 = 14.0), is an ideal T 1-T 2 dual-mode contrast agent at 1.5 T (r 2/r 1 = 6.52), and is also an effective T 1 contrast agent at 0.5 T (r 2/r 1 = 2.49), while 4-nm SPIO@PEG5k is a T 1-T 2 dual-mode contrast agent at 3.0 T (r 2/r 1 = 5.24), and is a useful T 1 contrast agent at 0.5 T (r 2/r 1 = 1.74) and 1.5 T (r 2/r 1 = 2.85). MRI studies in vivo at 3.0 T further confirm that 4-nm SPIO@PEG5k displays excellent T 1-T 2 dual-mode contrast enhancement, whereas 8-nm SPIO@PEG5k only displays T 2 contrast enhancement. CONCLUSION: PEGylated SPIOs with different nanocrystal sizes and PEG coating can be used as T 1, T 2, or T 1-T 2 dual-mode contrast agents to meet the clinical demands of MRI at specific magnetic fields.


Asunto(s)
Medios de Contraste/química , Nanopartículas Magnéticas de Óxido de Hierro/química , Imagen por Resonancia Magnética , Nanocompuestos/química , Polietilenglicoles/química , Animales , Campos Magnéticos , Nanopartículas Magnéticas de Óxido de Hierro/ultraestructura , Masculino , Ratones , Nanocompuestos/ultraestructura , Nanopartículas/química , Nanopartículas/ultraestructura , Tamaño de la Partícula , Células RAW 264.7 , Ratas Sprague-Dawley , Suero/metabolismo
19.
BMJ Open ; 11(1): e042084, 2021 01 11.
Artículo en Inglés | MEDLINE | ID: mdl-33431492

RESUMEN

OBJECTIVES: Emergency services utilisation is a critical policy concern. The paediatric population is the main user of emergency department (ED) services, and the main contributor to low acuity (LA) ED visits. We aimed to describe the trends of ED and LA ED visits under a comprehensive, universal health insurance programme in Taiwan, and to explore factors associating with potentially unnecessary ED utilisation. DESIGN AND SETTING: We used a population-based, repeated cross-sectional design to analyse the full year of 2000, 2005, 2010 and 2015 National Health Insurance claims data individually for individuals aged 18 years and under. PARTICIPANTS: We identified 5 538 197, 4 818 213, 4 401 677 and 3 841 174 children in 2000, 2005, 2010 and 2015, respectively. PRIMARY AND SECONDARY OUTCOME MEASURES: We adopted a diagnosis grouping system and severity classification system to define LA paediatric ED (PED) visits. Generalised estimating equation was applied to identify factors associated with LA PED visits. RESULTS: The annual LA PED visits per 100 paediatric population decreased from 10.32 in 2000 to 9.04 in 2015 (12.40%). Infectious ears, nose and throat, dental and mouth diseases persistently ranked as the top reasons for LA visits (55.31% in 2000 vs 33.94% in 2015). Physical trauma-related LA PED visits increased most rapidly between 2000 and 2015 (0.91-2.56 visits per 100 population). The dose-response patterns were observed between the likelihood of incurring LA PED visit and either child's age (OR 1.06-1.35 as age groups increase, p<0.0001) or family socioeconomic status (OR 1.02-1.21 as family income levels decrease, p<0.05). CONCLUSION: Despite a comprehensive coverage of emergency care and low cost-sharing obligations under a single-payer universal health insurance programme in Taiwan, no significant increase in PED utilisation for LA conditions was observed between 2000 and 2015. Taiwan's experience may serve as an important reference for countries considering healthcare system reforms.


Asunto(s)
Servicios Médicos de Urgencia , Cobertura Universal del Seguro de Salud , Adolescente , Niño , Estudios Transversales , Servicio de Urgencia en Hospital , Humanos , Seguro de Salud , Taiwán
20.
Anal Chem ; 82(6): 2355-62, 2010 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-20178318

RESUMEN

Poly(ethylene glycol) (PEG) is increasingly used in clinical and experimental medicine. However, quantification of PEG and PEGylated small molecules remains laborious and unsatisfactory. In this report, we stably expressed a functional anti-PEG antibody on the surface of BALB 3T3 cells (3T3/alphaPEG cells) to develop a competitive enzyme-linked immunosorbent assay (ELISA) for PEG quantification. The alphaPEG cell-coated plate bound biotinylated PEG(5K) (CH(3)-PEG(5K)-biotin) and CH(3)-PEG(5K)-(131)I more effectively than did a traditional anti-PEG antibody-coated plate. Competitive binding between PEG (2, 5, 10, or 20 kDa) and a known amount of CH(3)-PEG(5K)-biotin allowed construction of a reproducible competition curve. The alphaPEG cell-based competition ELISA measured small molecules derivatized by PEG(2K), PEG(5K), PEG(10K), PEG(20K), and PEG(5K) at concentrations as low as 58.6, 14.6, 3.7, 3.7, and 14.6 ng/mL, respectively. Notably, the presence of serum or bovine serum albumin enhanced PEG measurement by the alphaPEG cell-based competition ELISA. Finally, we show here that the alphaPEG cell-based competition ELISA accurately delineated the pharmacokinetics of PEG(5K), comparable to those determined by direct measurement of radioactivity in blood after intravenous injection of CH(3)-PEG(5K)-(131)I into mice. This quantitative strategy may provide a simple and sensitive method for quantifying PEG and PEGylated small molecules in vivo.


Asunto(s)
Anticuerpos/inmunología , Ensayo de Inmunoadsorción Enzimática/métodos , Polietilenglicoles/análisis , Polietilenglicoles/farmacocinética , Animales , Células 3T3 BALB , Bovinos , Femenino , Ratones , Suero/química , Albúmina Sérica Bovina/química
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