Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 25
Filtrar
1.
Mol Pharm ; 21(7): 3281-3295, 2024 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-38848439

RESUMEN

Renal fibrosis plays a key role in the pathogenesis of chronic kidney disease (CKD), in which the persistent high expression of transforming growth factor ß1 (TGF-ß1) and α-smooth muscle actin (α-SMA) contributes to the progression of CKD to renal failure. In order to improve the solubility, bioavailability, and targeting of tanshinone IIA (Tan IIA), a novel targeting material, aminoethyl anisamide-polyethylene glycol-1,2-distearoyl-sn-glycero-3-phosphate ethanolamine (AEAA-PEG-DSPE, APD) modified Tan IIA liposomes (APD-Tan IIA-L) was constructed. An animal model of glomerulonephritis induced by doxorubicin in BALB/c mice was established. APD-Tan IIA-L significantly decreased blood urea nitrogen and serum creatinine (SCr), and the consequences of renal tissue oxidative stress indicators showed that APD-Tan IIA-L downregulated malondialdehyde, upregulated superoxide dismutase, catalase, and glutathione peroxidase. Masson's trichrome staining showed that the deposition of collagen in the APD-Tan IIA-L group decreased significantly. The pro-fibrotic factors (fibronectin, collagen I, TGF-ß1, and α-SMA) and epithelial-mesenchymal transition marker (N-cadherin) were significantly inhibited by APD-Tan IIA-L. By improving the microenvironment of fibrotic kidneys, APD-Tan IIA-L attenuated TGF-ß1-induced excessive proliferation of fibroblasts and alleviated oxidative stress damage to the kidney, providing a new strategy for the clinical treatment of renal fibrosis.


Asunto(s)
Abietanos , Doxorrubicina , Fibrosis , Glomerulonefritis , Riñón , Liposomas , Ratones Endogámicos BALB C , Animales , Ratones , Liposomas/química , Abietanos/farmacología , Abietanos/química , Fibrosis/tratamiento farmacológico , Riñón/efectos de los fármacos , Riñón/patología , Riñón/metabolismo , Masculino , Glomerulonefritis/tratamiento farmacológico , Glomerulonefritis/inducido químicamente , Glomerulonefritis/patología , Factor de Crecimiento Transformador beta1/metabolismo , Estrés Oxidativo/efectos de los fármacos , Transición Epitelial-Mesenquimal/efectos de los fármacos , Modelos Animales de Enfermedad , Insuficiencia Renal Crónica/tratamiento farmacológico , Insuficiencia Renal Crónica/metabolismo , Insuficiencia Renal Crónica/patología , Insuficiencia Renal Crónica/inducido químicamente
2.
Ecotoxicol Environ Saf ; 281: 116681, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-38964063

RESUMEN

Fluoride exposure has been implicated as a potential risk factor for hypertension, but the underlying mechanisms remain unclear. This study investigated the role of the RhoA/ROCK signaling pathway in fluoride-induced hypertension. Male Wistar rats were divided into different groups and exposed to varying concentrations of sodium fluoride (NaF) or sodium chloride (NaCl) via drinking water. The rats' blood pressure was measured, and their aortic tissue was utilized for high-throughput sequencing analysis. Additionally, rat and A7r5 cell models were established using NaF and/or Fasudil. The study evaluated the effects of fluoride exposure on blood pressure, pathological changes in the aorta, as well as the protein/mRNA expression levels of phenotypic transformation indicators (a-SMA, calp, OPN) in vascular smooth muscle cells (VSMCs), along with the RhoA/ROCK signaling pathway (RhoA, ROCK1, ROCK2, MLC/p-MLC). The results demonstrated that fluoride exposure in rats led to increased blood pressure. High-throughput sequencing analysis revealed differential gene expression associated with vascular smooth muscle contraction, with the RhoA/ROCK signaling pathway emerging as a key regulator. Pathological changes in the rat aorta, such as elastic membrane rupture and collagen fiber deposition, were observed following NaF exposure. However, fasudil, a ROCK inhibitor, mitigated these pathological changes. Both in vitro and in vivo models confirmed the activation of the RhoA/ROCK signaling pathway and the phenotypic transformation of VSMCs from a contractile to a synthetic state upon fluoride exposure. Fasudil effectively inhibited the activities of ROCK1 and ROCK2 and attenuated the phenotypic transformation of VSMCs. In conclusion, fluoride has the potential to induce hypertension through the activation of the RhoA/ROCK signaling pathway and phenotypic changes in vascular smooth muscle cells. These results provide new insights into the mechanism of fluoride-induced hypertension.


Asunto(s)
Hipertensión , Músculo Liso Vascular , Ratas Wistar , Transducción de Señal , Quinasas Asociadas a rho , Animales , Quinasas Asociadas a rho/metabolismo , Masculino , Hipertensión/inducido químicamente , Músculo Liso Vascular/efectos de los fármacos , Músculo Liso Vascular/patología , Ratas , Transducción de Señal/efectos de los fármacos , Proteína de Unión al GTP rhoA/metabolismo , Fluoruro de Sodio/toxicidad , Miocitos del Músculo Liso/efectos de los fármacos , Miocitos del Músculo Liso/patología , Fenotipo , Presión Sanguínea/efectos de los fármacos , Fluoruros/toxicidad , Proteínas de Unión al GTP rho
3.
Drug Dev Ind Pharm ; 49(1): 139-148, 2023 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-36881020

RESUMEN

OBJECTIVE: To improve the solubility and targeting of Ginsenoside Rg3 (G-Rg3), in the current study, we constructed a novel targeting functional material folic acid -poly(2-ethyl-2-oxazoline)-cholesteryl methyl carbonate (FA-PEOz-CHMC, FPC) modified G-Rg3 liposomes (FPC-Rg3-L). METHODS: FPC was synthesized by using folic acid (FA) as a targeted head coupling with acid-activated poly(2-ethyl-2-oxazoline)-cholesteryl methyl carbonate. The inhibitory effects of the G-Rg3 preparations on mouse breast cancer cells (4T1) were investigated by CCK-8 assay. Paraffin sections of female BALB/c mice viscera were taken for hematoxylin-eosin (H&E) staining after continuous tail vein injection of G-Rg3 preparations. BALB/c mice bearing triple-negative breast cancer (TNBC) were used as animal models to investigate the inhibition of G-Rg3 preparations on tumor growth and improving quality of life. Transforming growth factor-ß1 (TGF-ß1) and α-smooth muscular actin (α-SMA) were used to investigate the expression of two fibrosis factors in tumor tissues by western blotting. RESULTS: Compared with G-Rg3 solution (Rg3-S) and Rg3-L, FPC-Rg3-L had a significant inhibitory effect on 4T1 cells (p < .01), and the half maximal inhibitory concentration (IC50) of FPC-Rg3-L was significantly lower (p < .01). The H&E results showed that the injection of FPC-Rg3-L and Rg3-S did not cause damage to the organs of mice. Compared with the control group, tumor growth was significantly inhibited in mice treated with FPC-Rg3-L and G-Rg3 solutions (p < .01). CONCLUSIONS: This study presents a new and safe treatment for TNBC, reduces the toxic and side effects of the drug, and provides a reference for the efficient use of Chinese herbal medicine components.


Asunto(s)
Ginsenósidos , Neoplasias de la Mama Triple Negativas , Humanos , Ratones , Femenino , Animales , Liposomas , Neoplasias de la Mama Triple Negativas/tratamiento farmacológico , Microambiente Tumoral , Calidad de Vida , Ginsenósidos/farmacología , Línea Celular Tumoral
4.
Fa Yi Xue Za Zhi ; 39(1): 18-26, 2023 Feb 25.
Artículo en Inglés, Zh | MEDLINE | ID: mdl-37038851

RESUMEN

OBJECTIVES: To realize the dynamic visualization of forensic odontology based on the bibliometrics methods, and capture the research hotspots and identify the future development trend. METHODS: Literature articles published from January 1995 to December 2020 were searched according to specific subject words in the core data set of Web of Science. The visualization analysis of publishing country, institution, discipline, author, co-cited journal and keywords was performed by CiteSpace 5.7.R5W software. RESULTS: The annual analysis of publications showed an upward trend of forensic odontology research literature year by year, with the number of annual publications more than 110 in the last five years. Developed countries were the main source of contributions and the average centrality was greater than 0.2. The research of forensic odontology involved multiple disciplines, including stomatology, biology, computer science and medical imaging, with a distinct interdisciplinary feature. A total of 115 nodes were obtained by keyword cluster analysis. The principal line of forensic odontology mainly included individual identification and age estimation and the emergence of hotspots was closely related to new technologies. Population-based odontology investigation, improvement of traditional dental age estimation method and dental age estimation based on new technology were popular research in forensic odontology. CONCLUSIONS: Developing countries urgently need to increase the focus on related research. It may be an important direction for the development of forensic odontology to establish and enrich the regional dental database, develop new odontology identification technology combined with frontier and high-end technology, and develop the identification program based on advanced information technology.


Asunto(s)
Medicina Legal , Programas Informáticos , Bibliometría
5.
Macromol Rapid Commun ; 42(19): e2100318, 2021 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-34347335

RESUMEN

Owing to deep activation in biotissues and enhanced targeting efficiency, developing photoresponsive polymer-upconversion nanoparticles (PP-UCNPs) nanovectors has witnessed rapid growth in the past decade. However, up to date, all developed nanovectors require high-order photon processes to initiate the release of cargos. The photodamage caused by high-power near-infrared laser light may be a critical obstacle to their clinical application. Here, for the first time, by leveraging absorption-emission spectral matching between donor-acceptor Stenhouse adducts (DASA) PP and UCNPs (λex , 808 nm) in the green region (≈530 nm), the designed nanovector is capable of releasing cargos at a low-power 808 nm excitation (0.2 W). Considering the high molar absorptivity, biobenign, and synthetic tunability of DASA, DASA PP can be utilized as an up-and-coming candidate to design and synthesize the next generation of upconversion nanovectors without photodamage.


Asunto(s)
Nanopartículas , Polímeros , Rayos Infrarrojos
6.
BMC Vet Res ; 16(1): 336, 2020 Sep 15.
Artículo en Inglés | MEDLINE | ID: mdl-32933523

RESUMEN

BACKGROUND: Mastitis is the most common health concern plaguing the modern dairy cow and costs dairy producers estimates of two billion dollars annually. Staphylococcus aureus infections are prevalent, displaying varied disease presentation and markedly low cure rates. Neutrophils are considered the first line of defense against mastitis causing bacteria and are frequently targeted in the development of treatment and prevention technologies. We describe a case of naturally occurring, chronic mastitis in a Holstein cow (1428), caused by a novel strain of S. aureus that was not able to be cleared by antibiotic treatment. CASE PRESENTATION: The infection was identified in a single quarter, 2 months into the cow's first lactation. The infection persisted for the following 20 months, including through dry off, and a second calving and lactation. This case of mastitis was associated with a consistently high somatic cell count, however presented with no other clinical signs. This cow was unsuccessfully treated with antibiotics commonly used to treat mastitis, consisting of two rounds of treatment during lactation and an additional round at the beginning of dry off. The chronic infection was also unchanged through an experimental mid-lactation treatment with pegylated granulocyte-colony stimulating factor (PEG-gCSF) and an additional periparturient treatment with PEG-gCSF. We isolated milk neutrophils from 1428 and compared them to two cows challenged with experimental S. aureus, strain Newbould 305. Neutrophils from 1428's milk had higher surface expression of myeloperoxidase compared to experimental Newbould challenged animals, as well as increased presence of Neutrophil Extracellular Traps. This suggests a heightened activation state of neutrophils sourced from 1428's naturally occurring infection. Upon postmortem examination, the affected quarter revealed multifocal abscesses separated by fibrous connective tissues. Abscesses were most common in the gland cistern and collecting duct region. Microscopically, the inflammatory reaction was pyogranulomatous to granulomatous and consistent with botryomycosis. Colonies of Gram-positive cocci were found within the eosinophilic matrix of the Splendore-Hoeppli reaction within granulomas and intracellularly within the acinar epithelium. CONCLUSIONS: Collectively, we describe a unique case of chronic mastitis, the characterization of which provides valuable insight into the mechanics of S. aureus treatment resistance and immune escape.


Asunto(s)
Mastitis Bovina/microbiología , Neutrófilos/enzimología , Infecciones Estafilocócicas/veterinaria , Absceso/microbiología , Absceso/veterinaria , Animales , Antibacterianos/uso terapéutico , Bovinos , Enfermedad Crónica/veterinaria , Femenino , Factor Estimulante de Colonias de Granulocitos/uso terapéutico , Mastitis Bovina/tratamiento farmacológico , Leche/citología , Peroxidasa/metabolismo , Polietilenglicoles/uso terapéutico , Proteínas Recombinantes/uso terapéutico , Infecciones Estafilocócicas/tratamiento farmacológico , Staphylococcus aureus/efectos de los fármacos
7.
J Nanobiotechnology ; 17(1): 91, 2019 Aug 26.
Artículo en Inglés | MEDLINE | ID: mdl-31451114

RESUMEN

BACKGROUND: The selectively accumulate in tumor site and completely release drug within cancer cells great limit the therapeutic effect of nano-drug delivery system. Moreover, absence of appropriate biomarker is one of the major challenges for prostate specific membrane antigen negative (PSMA (-)) prostate cancer therapy. RESULTS: Herein, a PSMA (-) prostate cancer specific targeted and intracellular reactive oxygen species (ROS) amplification for ROS-responsive self-accelerating drug release nanoplatform (ATD-NPs) was developed. ATD-NPs was formed by three parts, including PSMA (-) prostate cancer specifically targeted part (DUP-PEG-DSPE), ROS-sensitive doxorubicin (DOX) polymeric prodrug (P(L-TK-DOX)), and the ROS generation agent (α-tocopheryl succinate, α-TOS); and this delivery system is expected to enhance PSMA (-) prostate cancer therapeutic effect, increase selective accumulation at tumor site and overcome intracellular incomplete drug release. After administration i.v injection, ATD-NPs could specifically accumulate in tumor site and markedly be internalized by cancer cells based on the DUP-1 (a PSMA (-) cancer cells specific target peptide). Subsequently, ATD-NPs could be dissociated under the high concentration reactive oxygen species (ROS) condition, resulting in DOX and α-TOS release. Then, the released α-TOS could be reacted with mitochondria to produce ROS, which in turn accelerating the release of drugs. Finally achieved the purpose of enhancing therapeutic efficacy and reducing side effect. Both in vitro and in vivo experiments demonstrated that the combination of tumor actively-targeted and self-amplifying ROS-responsive drug release showed more significant antitumor activity in the human PSMA (-) prostate cancer. CONCLUSION: The described technology unifies the tumor actively targets, self-amplified drug release, and excellent biocompatibility into one formulation, are promising for cancer treatment.


Asunto(s)
Antígenos de Superficie/metabolismo , Glutamato Carboxipeptidasa II/metabolismo , Nanopartículas/química , Polímeros/química , Profármacos/química , Profármacos/farmacología , Neoplasias de la Próstata/tratamiento farmacológico , Especies Reactivas de Oxígeno/metabolismo , Animales , Línea Celular Tumoral , Doxorrubicina/química , Doxorrubicina/farmacología , Sistemas de Liberación de Medicamentos/métodos , Liberación de Fármacos/efectos de los fármacos , Humanos , Masculino , Ratones , Células PC-3 , Próstata/efectos de los fármacos , Próstata/metabolismo , Neoplasias de la Próstata/metabolismo
8.
Molecules ; 23(1)2017 Dec 24.
Artículo en Inglés | MEDLINE | ID: mdl-29295557

RESUMEN

A biomass-based catalyst with amine groups (-NH2), viz., amine-functionalized sugarcane bagasse (SCB-NH2), was prepared through the amination of sugarcane bagasse (SCB) in a two-step process. The physicochemical properties of the catalyst were characterized through FT-IR, elemental analysis, XRD, TG, and SEM-EDX techniques, which confirmed the -NH2 group was grafted onto SCB successfully. The catalytic performance of SCB-NH2 in Knoevenagel condensation reaction was tested in the batch and continuous flow reactions. Significantly, it was found that the catalytic performance of SCB-NH2 is better in flow system than that in batch system. Moreover, the SCB-NH2 presented an excellent catalytic activity and stability at the high flow rate. When the flow rate is at the 1.5 mL/min, no obvious deactivation was observed and the product yield and selectivity are more than 97% and 99% after 80 h of continuous reaction time, respectively. After the recovery of solvent from the resulting solution, a white solid was obtained as a target product. As a result, the SCB-NH2 is a promising catalyst for the synthesis of fine chemicals by Knoevenagel condensation reaction in large scale, and the modification of the renewable SCB with -NH2 group is a potential avenue for the preparation of amine-functionalized catalytic materials in industry.


Asunto(s)
Aminas/química , Biotecnología/métodos , Celulosa/química , Saccharum/química , Temperatura , Catálisis , Solventes/química , Espectroscopía Infrarroja por Transformada de Fourier , Difracción de Rayos X
9.
Int J Biol Macromol ; 259(Pt 1): 128972, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38151086

RESUMEN

Emulsification viscosity reduction and subsequent demulsification are effective strategies to improve the utilization rate of heavy oil. However, traditional surfactants are challenged by unsatisfactory salt tolerance, inadequate stability in emulsification, difficulty in demulsification and pollution problem of oily wastewater discharge. To realize the feasibility and environment-friendliness of heavy oil utilization in the harsh reservoir environments, we designed a functional polymer and conducted a comprehensive evaluation using heavy oil samples from Chenping oil well in Shengli Oilfield. It was synthesized by grafting two hydrophobic monomers, lauryl methacrylate (LMA) and N, N-Diethylaminomethyl methacrylate (DEAEMA), onto the hydrophilia hydroxyethyl cellulose (HEC) by free-radical polymerization. The viscosity reduction rate can reach 99.57 % even under the high salinity of 26,050 mg/L. The stable oil-in-water (O/W) emulsion can be maintained for >48 h, satisfying the actual requirements for heavy oil recovery. Moreover, the emulsion can be completely demulsified in a CO2 atmosphere within 30 min, suggesting its satisfactory demulsification performance. Our study achieved the one-step transformation of heavy oil emulsion between emulsification and demulsification, which provides a green bio-based material and an ingenious strategy for enhanced oil recovery and other chemical engineering applications including oil/water separation.


Asunto(s)
Aceites , Polímeros , Polímeros/química , Emulsiones/química , Celulosa/química , Tensoactivos/química
10.
Int J Biol Macromol ; 254(Pt 3): 128028, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-37952806

RESUMEN

Oligosaccharide-containing macromolecular bio adhesives are emerging as highly promising eco-friendly materials to enhance the cytocompatibility of viscous hydrogels for wound healing applications. In our prior research, we extensively elucidated the properties of branch-structure fructo-oligosaccharides derived from Polygonatum Cyrtonema Hua (referred to as PCOS). However, the characteristics of hydrogels based on fructo-oligosaccharides remain to be fully explored. In present work, we developed an injectable, PCOS/carboxymethyl cellulose (CMC) hydrogel which is a dual ion-physical cross-linked hydrogel that can be considered as a potential diabetic wound dressing. The tests showed that the optimal ratios for hydrogel preparation were 2 % CBM 940 (Carbomer 940), 5 % CMC and 10 % PCOS. The resultant hydrogel was formulated into composite hydrogels that were then used for the treatment of full-thickness excisional wounds in a db/db diabetic mouse model. Wound closure and histological evaluation confirmed its beneficial effect on wound healing. Further morphological analysis through scanning electron microscopy images revealed a porous hydrogel structure, while Fourier-transform infrared spectroscopy provided structural insights on the crosslinking reaction. Physicochemical properties of the hybrid hydrogels determined by rheological properties, thermogravimetric, water loss rate, et al., indicated that the double crosslinking PCOS/CMC hybrid hydrogel showed enhanced dynamic mechanical properties and water retention capacity compared to the CMC cellulose matrix hydrogels. Thus, this novel PCOS-hybrid hydrogel exhibited good dissolvability and injectable properties, which was proved to facilitate for the diabetic wound healing both in vitro and in vivo test and holds a potential clinical application in the wound healing.


Asunto(s)
Diabetes Mellitus , Síndrome del Ovario Poliquístico , Polygonatum , Humanos , Ratones , Animales , Femenino , Hidrogeles/química , Celulosa/farmacología , Celulosa/química , Síndrome del Ovario Poliquístico/tratamiento farmacológico , Oligosacáridos , Diabetes Mellitus/tratamiento farmacológico , Agua , Antibacterianos/uso terapéutico
11.
Sci Total Environ ; 901: 166551, 2023 Nov 25.
Artículo en Inglés | MEDLINE | ID: mdl-37633377

RESUMEN

Microplastics are ubiquitous in the natural environment, which inevitably affect the relevant biochemical process. Nevertheless, the knowledge about the impacts of microplastics on organics transformation and corresponding microbial metabolism response in anaerobic environment is limited. Here, polystyrene (PS) microplastics were selected as model microplastics to explore their potential impacts on organics transformation, microbial community and metabolic pathway during sludge anaerobic digestion system operation. The results indicated that the PS microplastics exhibited the dose-dependent effects on methane production, i.e., the additive of 20-40 particles/g TS of PS microplastics improved the maximum methane yield by 3.38 %-8.22 %, whereas 80-160 particles/g TS additive led to a 4.78 %-11.04 % declining. Overall, PS microplastics facilitated the solubilization and hydrolysis of sludge, but inhibited the acidogenesis process. Key functional enzyme activities were stimulated under low PS microplastics exposure, whereas were almost severely inhibited due to the increased oxidative stress induced from excess PS microplastics. Microbial community and further metabolic analysis indicated that low PS microplastics improved the acetotrophic and hydrogenotrophic methanogenesis, while a high level of PS microplastics shifted methanogenesis from acetotrophic to hydrogenotrophic pathway. Further analysis showed that the reacted PS microplastics exhibited greater toxicity and ecological than the raw PS microplastics due to that they are more likely to adsorb contaminants. These findings revealed the dosage-dependent relationships between microplastics and organics transformation process in anaerobic environments, providing new insights for assessing the impact of PS microplastics on sludge anaerobic digestion.


Asunto(s)
Microbiota , Aguas del Alcantarillado , Microplásticos/toxicidad , Poliestirenos/toxicidad , Plásticos/toxicidad , Anaerobiosis , Eliminación de Residuos Líquidos/métodos , Reactores Biológicos , Metano , Redes y Vías Metabólicas
12.
Int J Biol Macromol ; 225: 1172-1181, 2023 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-36414081

RESUMEN

A new design for chiral photonic cellulose nanocrystal films was developed by co-assembling lanthanide-doped nanorods (NRs) into chiral cellulose nanocrystals, in which the photonic band gap (PBG) could be tuned in the visible range by changing the mass fraction of flexible agents, such as polyvinyl alcohol (PVA) and ethylene glycol (EG). Due to the PBG effect, the luminescence modulation in such nanocrystal films had been realized. The down-conversion luminescence from NaGd30Y60F4:5%Tb3+, 5%Eu3+ NRs and up-conversion luminescence from NaGd40Y40F4:18%Yb3+, 2%Er3+ NRs could be enhanced by 28 % and 18 % respectively, on account of the band edge effect. The luminescence would be inhibited when the luminescence overlapped with the stop band of the PBG. These results implied that the biocompatible photonic cellulose nanocrystal films are ideally suited for applications in optical coding, optical resonators and biocompatible lasers.


Asunto(s)
Elementos de la Serie de los Lantanoides , Nanopartículas , Nanotubos , Luminiscencia , Celulosa/química , Nanotubos/química , Nanopartículas/química
13.
Shanghai Kou Qiang Yi Xue ; 31(3): 282-285, 2022 Jun.
Artículo en Zh | MEDLINE | ID: mdl-36204957

RESUMEN

PURPOSE: To investigate the related factors of black tooth stain in primary teeth of 3~5 years old children and caries status of primary dentition in these children. METHODS: From December 2019 to August 2020, 182 3~5 years old children with black tooth stain and 200 children without pigmentation were investigated by oral examination and questionnaire survey to their guardians, while caries status , distribution range of the pigment, factors associated with black tooth stain were evaluated. SPSS 20.0 software package was used for data analysis. RESULTS: Children with black tooth stain had fewer dental caries. The lingual surfaces of the mandibular anterior teeth were the most affected sites. Factors associated with black tooth stain were foods with soy sauce and brushing teeth with parents' help. CONCLUSIONS: There is a negative correlation between the occurrence of primary dentition caries and blacktooth stain, but there is no significant correlation between formation of black tooth stain and most environmental factors.


Asunto(s)
Caries Dental , Decoloración de Dientes , Niño , Preescolar , Caries Dental/epidemiología , Susceptibilidad a Caries Dentarias , Humanos , Prevalencia , Decoloración de Dientes/diagnóstico , Diente Primario , Cepillado Dental
14.
Int J Biol Macromol ; 201: 400-410, 2022 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-34995668

RESUMEN

The application of industrial kraft lignin is limited by its low molecular weight, dark color, and low solubility. In this work, an efficient crosslinking reaction with N,N-Dimethylformamide (DMF) and 1,6-dibromohexane was proposed for adjusting the molecular weight and color of lignin. The chemical structure of alkylation lignin was systematically investigated by gel permeation chromatography (GPC), ultraviolet spectroscopy, Fourier transform infrared (FT-IR) spectroscopy, and 2D heteronuclear single quantum correlation nuclear magnetic resonance (HSQC NMR) spectra. After the alkylation modification, the molecular weights of the lignin were increased to 1643%. The resinol (ß-ß), ß-aryl ether (ß-O-4), and phenylcoumaran (ß-5) linkages were still the main types of the linkages. The formation of ß-ß linkage would be inhibited at high temperatures. The color reduction of lignin can be attributed to the low content of chromophores and low packing density. This alkylation lignin will be a new and general approach for developing molecular weight-controlled and light-colored lignins, which can find more applications in cosmetics, packing, and other fields.


Asunto(s)
Lignina , Alquilación , Cromatografía en Gel , Lignina/química , Estructura Molecular , Peso Molecular , Espectroscopía Infrarroja por Transformada de Fourier
15.
Ann Vasc Surg ; 25(4): 538-46, 2011 May.
Artículo en Inglés | MEDLINE | ID: mdl-21549923

RESUMEN

BACKGROUND: Nanoparticles (NPs) possess several advantages as a carrier system for intracellular delivery of therapeutic agents. Rapamycin is an immunosuppressive agent which also exhibits marked antiproliferative properties. We investigated whether rapamycin-loaded NPs can reduce neointima formation of vein graft disease in a rat model. METHODS: Poly(lactic-co-glycolic acid) (PLGA) NPs-containing rapamycin was prepared using an oil/water solvent evaporation technique. The size and morphology of the NP were determined by dynamic light scattering methodology and electron microscopy. In vitro cytotoxicity of blank, rapamycin-loaded PLGA NPs was studied using 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide assay. Excised rat jugular vein was treated ex vivo with blank NPs, or rapamycin-loaded NPs, and then interposed back into the carotid artery position using a cuff technique. Grafts were harvested for 21 days and subjected to morphometric analysis as well as immunohistochemical analysis and Western blotting. RESULTS: Rapamycin was efficiently loaded in PLGA NPs with an encapsulation efficiency of 87.6%. The average diameter of NPs was 180.3 nm. The NPs-containing rapamycin at 1 ng/mL significantly inhibited vascular smooth muscular cells proliferation. Measurement of rapamycin levels in vein grafts showed that the concentration of rapamycin in vein grafts at 3 weeks after grafting was 0.9 ± 0.1 µg/g. In grafted veins without treatment, intima-media thickness was 300.4 ± 181.5 µm at 21 days after grafting, whereas veins treated with rapamycin-loaded NPs showed a reduction of intimal-media thickness of 150.2 ± 62.5 µm (p = 0.001). Cell proliferation was measured by proliferating cell nuclear antigen immunohistochemistry staining. As expected, proliferating cell nuclear antigen index declined from 83.4% ± 7.4% to 66.2% ± 4.5% in vein grafts after 3 weeks (p = 0.002). Platelet endothelial cell adhesion molecule (PECAM-1/CD31) staining was used to measure luminal endothelial coverage in grafts and indicated a high level of endothelialization at 21 days after grafting, with no significant effect of blank or rapamycin-loaded NPs group. Western blot analysis showed that treatment with rapamycin-loaded PLGA NPs markedly attenuated phosphorylation and activation of S6 kinase 1 phosphorylation and inactivation of 4E (eIF4E)-binding protein 1, both in vascular smooth muscular cells and vein grafts at 7 and 21 days after grafting. CONCLUSIONS: We conclude that sustained-release rapamycin from rapamycin-loaded NPs inhibits vein graft thickening without affecting the endothelial cells in rat carotid vein-to-artery interposition grafts; thus, this may be a promising therapy for the treatment of vein graft disease.


Asunto(s)
Fármacos Cardiovasculares/administración & dosificación , Proliferación Celular/efectos de los fármacos , Supervivencia de Injerto/efectos de los fármacos , Venas Yugulares/efectos de los fármacos , Nanopartículas , Sirolimus/administración & dosificación , Túnica Íntima/efectos de los fármacos , Injerto Vascular/efectos adversos , Animales , Western Blotting , Fármacos Cardiovasculares/química , Fármacos Cardiovasculares/farmacocinética , Arterias Carótidas/cirugía , Proteínas Portadoras/metabolismo , Células Cultivadas , Preparaciones de Acción Retardada , Portadores de Fármacos , Células Endoteliales/efectos de los fármacos , Células Endoteliales/metabolismo , Hiperplasia , Inmunohistoquímica , Péptidos y Proteínas de Señalización Intracelular , Venas Yugulares/metabolismo , Venas Yugulares/patología , Venas Yugulares/trasplante , Ácido Láctico/química , Luz , Masculino , Microscopía Electrónica de Transmisión , Músculo Liso Vascular/efectos de los fármacos , Músculo Liso Vascular/metabolismo , Músculo Liso Vascular/patología , Miocitos del Músculo Liso/efectos de los fármacos , Miocitos del Músculo Liso/metabolismo , Miocitos del Músculo Liso/patología , Fosfoproteínas/metabolismo , Fosforilación , Molécula-1 de Adhesión Celular Endotelial de Plaqueta/metabolismo , Ácido Poliglicólico/química , Copolímero de Ácido Poliláctico-Ácido Poliglicólico , Ratas , Ratas Sprague-Dawley , Proteínas Quinasas S6 Ribosómicas/metabolismo , Dispersión de Radiación , Sirolimus/química , Sirolimus/farmacocinética , Solubilidad , Túnica Íntima/metabolismo , Túnica Íntima/patología , Túnica Íntima/trasplante
16.
Shanghai Kou Qiang Yi Xue ; 30(3): 278-282, 2021 Jun.
Artículo en Zh | MEDLINE | ID: mdl-34476445

RESUMEN

PURPOSE: To investigate the effect of improved atraumatic restorative treatment(ART) with high-strength glass ionomer cement in the treatment of primary caries in children. METHODS: From August 2018 to May 2019, 262 children with primary tooth caries who were treated in Children's Hospital of Nanjing Medical University were selected into our study, prospectively. The children were divided into two groups, randomly: ART group (131 cases, 177 teeth) and control group (131 cases, 178 teeth). Children in the control group were treated with conventional cavity preparation and composite resin filling, while those in the ART group were treated with improved high-intensity glass ionomer. The curative effect and satisfaction degree were compared between the two groups. SPSS 19.0 software package was used for data analysis. RESULTS: The overall curative effect in the ART group was better than that of the control group. The cooperation degree of the 2~4 years old children in the ART group was significantly higher than that of the control group(P<0.05). The cooperation degree of the 5 years old children between the two groups had no significant differences(P>0.05). Both groups of children accepted 12 months of follow-up. Three months after treatment, the rate of secondary caries in the ART group was significantly lower than that in the control group, but it was not statistically significant(P>0.05). Six and 12 months after treatment, the rate of secondary caries in the ART group were significantly lower than that in the control group(P<0.05), and the satisfaction of parents in the ART group was significantly higher than that in the control group (P<0.05). CONCLUSIONS: Improved ART with high-intensity glass ionomer cement is more likely accepted by children and their parents, with more willing to accept and cooperate with the treatment. Not only is it easy to operate, but also has a reliable curative effect in children.


Asunto(s)
Tratamiento Restaurativo Atraumático Dental , Caries Dental , Niño , Preescolar , Caries Dental/terapia , Susceptibilidad a Caries Dentarias , Preparación de la Cavidad Dental , Restauración Dental Permanente , Cementos de Ionómero Vítreo/uso terapéutico , Humanos
17.
Bioresour Technol ; 309: 123351, 2020 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-32289658

RESUMEN

In this study, lignin with different phenolic hydroxyl contents and five model compounds are pyrolyzed to investigate the effect of the interaction of phenolic hydroxyl with a benzene ring on lignin pyrolysis. The results demonstrated that phenolic hydroxyl can reduce the stability of lignin and promote the elimination of the side chain on lignin during pyrolysis. The repolymerization during lignin pyrolysis, which results in increased activation energy and char yield during pyrolysis, can be mainly attributed to phenolic hydroxyl. Meanwhile, the repolymerization because of phenolic hydroxyl is obviously affected by the electron cloud density of the benzene ring. The repolymerization caused by the phenolic hydroxyl can be effectively reduced by increasing the electron cloud density. Furthermore, regulation of the product distribution obtained via lignin pyrolysis by changing the electron cloud density of the benzene ring and the phenolic hydroxyl content in lignin is proposed.


Asunto(s)
Lignina , Pirólisis , Benceno , Radical Hidroxilo , Fenoles
18.
Bioresour Technol ; 317: 124034, 2020 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-32829115

RESUMEN

In this work, an emerging and efficient strategy for the preparation of lignin samples with different acetylation degree by choline chloride/acetic anhydride (ChCl/Aa) treatment of pine kraft lignin (PKL) is reported, and the effects of efficient pre-acetylation of hydroxyl functional groups on subsequent lignin pyrolysis are also systematically investigated. The results show that the ChCl/Aa displays a high acetylation efficiency towards the aliphatic hydroxyl (~99.1%) and phenolic hydroxyl (~94.0%) of PKL, which enhances the hydrogen to carbon effective ratio of PKL. Noticeably, the ChCl/Aa has a slight effect on ß-O-4 of PKL, and the acetylation of hydroxyl is beneficial for the improvement of the maximum degradation rate of PKL. In addition, the acetylation of hydroxyl is also significantly contributed to the increment of the pyrolysis bio-oil yield. Importantly, the relative content of the H-phenols obtained from acetylated lignins pyrolysis shows a positive correlation with the acetylation degree of hydroxyl.


Asunto(s)
Lignina , Pirólisis , Anhídridos Acéticos , Acetilación , Colina
19.
Bioresour Technol ; 310: 123460, 2020 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-32402988

RESUMEN

In this work, several representative green processes were developed to extract the enzymatic lignin and deep eutectic solvents (DESs) isolated lignin from corn straw. The results revealed that enzymatic lignin and DESs isolated lignin had a relatively low and homogeneous molecular weight and DESs isolated lignin shown a higher purity. Enzymatic and DESs isolated lignin showed good representativeness and similar to original herbal lignin structures accompany few aryl ether linkage cleavages and oxidation phenomenon. Among them, the subcritical CO2-assisted autohydrolysis and ChCl/Lac DESs treatment exhibited a higher severity for lignin preparation, and sequence DESs isolated lignin had a better reactivity. The ß-O-4 ether bonds and carbon-carbon bonds linkage were further broken up during the Lac and DESs sequence treatment. In short, the described processes showed practical significance for lignin extraction and potential valorization, as well as help to develop more novel strategies for the current biorefinery process.


Asunto(s)
Lignina , Zea mays , Biomasa , Solventes
20.
Macromol Biosci ; 20(12): e2000268, 2020 12.
Artículo en Inglés | MEDLINE | ID: mdl-32924320

RESUMEN

The role viscoelasticity in fibrotic disease progression is an emerging area of interest. Here, a fast-relaxing hydrogel system is exploited to investigate potential crosstalk between calcium signaling and mechanotransduction. Poly(ethylene glycol) (PEG) hydrogels containing boronate and triazole crosslinkers are synthesized, with varying ratios of boronate to triazole crosslinks to systematically vary the extent of stress relaxation. Valvular interstitial cells (VICs) encapsulated in hydrogels with the highest levels of stress relaxation (90%) exhibit a spread morphology by day 1 and are highly aligned (80 ± 2%) by day 5. Key myofibroblast markers, including α-smooth muscle actin (αSMA) and collagen 1a1 (COL1A1), are significantly elevated. VIC myofibroblast activation decreases by 42 ± 18% through inhibition of mechanotransduction, independently of VIC morphology and alignment. Calcium signaling through a transient receptor potential vanilloid 4 (TRPV4) is found to regulate VIC spreading, alignment, and activation in a time dependent manner. Inhibition of calcium signaling at early time points results in disturbed cell alignment, decreased mechanotransduction, and diminished activation, while inhibition at later time points only causes partially reduced myofibroblast activation. These results suggest a potential crosstalk mechanism, where calcium signaling acts upstream of mechanosensing and can regulate VIC myofibroblast activation independently of mechanotransduction.


Asunto(s)
Señalización del Calcio/efectos de los fármacos , Fibrosis/tratamiento farmacológico , Hidrogeles/farmacología , Mecanotransducción Celular/efectos de los fármacos , Animales , Colágeno Tipo I/genética , Fibrosis/genética , Fibrosis/patología , Regulación de la Expresión Génica/efectos de los fármacos , Humanos , Hidrogeles/química , Ratones , Miofibroblastos/efectos de los fármacos , Miofibroblastos/metabolismo , Polietilenglicoles/química , Polietilenglicoles/farmacología , Porcinos , Canales Catiónicos TRPV/genética , Triazoles/química , Triazoles/farmacología , Sustancias Viscoelásticas/química , Sustancias Viscoelásticas/farmacología
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA