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1.
BMC Gastroenterol ; 23(1): 412, 2023 Nov 27.
Artículo en Inglés | MEDLINE | ID: mdl-38012582

RESUMEN

BACKGROUND: Novel endoscopic techniques used in the treatment of gastric lesions with local submucosal fibrosis need preclinical evaluation and training due to safety limitations. Therefore, the purpose of our study was to establish an animal model of gastric local fibrotic target lesions and assess its feasibility in the evaluation and training of endoscopic techniques. METHODS: In six experimental beagles, a 50% glucose solution was injected into three submucosal areas of the fundus, body, and antrum of the stomach to create gastric local fibrotic target lesions (experimental group). On post-injection day (PID) 7, the injection sites were assessed endoscopically to confirm the presence of submucosal fibrosis formation, and the dental floss clip traction assisted endoscopic submucosal dissection (DFC-ESD) procedure was performed on the gastric local fibrotic target lesions to confirm its feasibility after endoscopic observation. The normal gastric mucosa of six control beagles underwent the same procedure (control group). All the resected specimens were evaluated by histological examination. RESULTS: All 12 beagles survived without postoperative adverse events. On PID 7, 16 ulcer changes were observed at the injection sites (16/18) under the endoscope, and endoscopic ultrasonography confirmed the local submucosal fibrosis formation in all ulcer lesions. The subsequent DFC-ESD was successfully performed on the 32 gastric target lesions, and the mean submucosal dissection time in the ulcer lesions was greater than that in the normal gastric mucosa (15.3 ± 5.6 vs. 6.8 ± 0.8 min; P < 0.001). There was no difference in rates of en bloc resection, severe hemorrhage, or perforation between the two groups. Histological analysis of the ulcer lesions showed the absence of epithelial or muscularis mucosae and extensive submucosal fibrous tissue proliferations compared with normal gastric mucosa. Overall, endoscopists had high satisfaction with the realism and feasibility of the animal model. CONCLUSION: We developed a novel animal model of gastric local fibrotic target lesions to simulate difficult clinical situations, which strongly appeared to be suitable for the preclinical evaluation and learning of advanced endoscopic techniques.


Asunto(s)
Resección Endoscópica de la Mucosa , Fibrosis de la Submucosa Bucal , Neoplasias Gástricas , Perros , Animales , Úlcera/patología , Fibrosis de la Submucosa Bucal/patología , Mucosa Gástrica/patología , Endoscopía , Neoplasias Gástricas/patología , Resección Endoscópica de la Mucosa/métodos , Resultado del Tratamiento
2.
Acta Pharmacol Sin ; 44(10): 1962-1976, 2023 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-37169852

RESUMEN

Atherosclerosis is a major cause of death and disability in cardiovascular disease. Atherosclerosis associated with lipid accumulation and chronic inflammation leads to plaques formation in arterial walls and luminal stenosis in carotid arteries. Current approaches such as surgery or treatment with statins encounter big challenges in curing atherosclerosis plaque. The infiltration of proinflammatory M1 macrophages plays an essential role in the occurrence and development of atherosclerosis plaque. A recent study shows that TRIM24, an E3 ubiquitin ligase of a Trim family protein, acts as a valve to inhibit the polarization of anti-inflammatory M2 macrophages, and elimination of TRIM24 opens an avenue to achieve the M2 polarization. Proteolysis-targeting chimera (PROTAC) technology has emerged as a novel tool for the selective degradation of targeting proteins. But the low bioavailability and cell specificity of PROTAC reagents hinder their applications in treating atherosclerosis plaque. In this study we constructed a type of bioinspired PROTAC by coating the PROTAC degrader (dTRIM24)-loaded PLGA nanoparticles with M2 macrophage membrane (MELT) for atherosclerosis treatment. MELT was characterized by morphology, size, and stability. MELT displayed enhanced specificity to M1 macrophages as well as acidic-responsive release of dTRIM24. After intravenous administration, MELT showed significantly improved accumulation in atherosclerotic plaque of high fat and high cholesterol diet-fed atherosclerotic (ApoE-/-) mice through binding to M1 macrophages and inducing effective and precise TRIM24 degradation, thus resulting in the polarization of M2 macrophages, which led to great reduction of plaque formation. These results suggest that MELT can be considered a potential therapeutic agent for targeting atherosclerotic plaque and alleviating atherosclerosis progression, providing an effective strategy for targeted atherosclerosis therapy.


Asunto(s)
Aterosclerosis , Placa Aterosclerótica , Quimera Dirigida a la Proteólisis , Animales , Ratones , Antiinflamatorios/uso terapéutico , Aterosclerosis/tratamiento farmacológico , Aterosclerosis/metabolismo , Inflamación/tratamiento farmacológico , Macrófagos , Ratones Endogámicos C57BL , Placa Aterosclerótica/tratamiento farmacológico , Placa Aterosclerótica/metabolismo , Quimera Dirigida a la Proteólisis/farmacología , Quimera Dirigida a la Proteólisis/uso terapéutico , Copolímero de Ácido Poliláctico-Ácido Poliglicólico/farmacología , Nanopartículas/uso terapéutico
3.
Int J Mol Sci ; 24(12)2023 Jun 18.
Artículo en Inglés | MEDLINE | ID: mdl-37373449

RESUMEN

The structure of cellulolytic enzyme lignin (CEL) prepared from three bamboo species (Neosinocalamus affinis, Bambusa lapidea, and Dendrocalamus brandisii) has been characterized by different analytical methods. The chemical composition analysis revealed a higher lignin content, up to 32.6% of B. lapidea as compared to that of N. affinis (20.7%) and D. brandisii (23.8%). The results indicated that bamboo lignin was a p-hydroxyphenyl-guaiacyl-syringyl (H-G-S) lignin associated with p-coumarates and ferulates. Advanced NMR analyses displayed that the isolated CELs were extensively acylated at the γ-carbon of the lignin side chain (with either acetate and/or p-coumarate groups). Moreover, a predominance of S over G lignin moieties was found in CELs of N. affinis and B. lapidea, with the lowest S/G ratio observed in D. brandisii lignin. Catalytic hydrogenolysis of lignin demonstrated that 4-propyl-substituted syringol/guaiacol and propanol guaiacol/syringol derived from ß-O-4' moieties, and methyl coumarate/ferulate derived from hydroxycinnamic units were identified as the six major monomeric products. We anticipate that the insights of this work could shed light on the sufficient understanding of lignin, which could open a new avenue to facilitate the efficient utilization of bamboo.


Asunto(s)
Bambusa , Lignina , Lignina/química , Pirogalol , Bambusa/química , Catálisis
4.
Molecules ; 27(8)2022 Apr 08.
Artículo en Inglés | MEDLINE | ID: mdl-35458619

RESUMEN

Tumor penetration and the accumulation of nanomedicines are crucial challenges in solid tumor therapy. By taking advantage of the MSC tumor-tropic property, we developed a mesenchymal stem cell (MSC)-based drug delivery system in which paclitaxel (PTX)-encapsulating hyaluronic acid-poly (D,L-lactide-co-glycolide) polymeric micelles (PTX/HA-PLGA micelles) were loaded for glioma therapy. The results indicated that CD44 overexpressed on the surface of both MSCs and tumor cells not only improved PTX/HA-PLGA micelle loading in MSCs, but also promoted the drug transfer between MSCs and adjacent cancer cells. It was hypothesized that CD44-mediated transcytosis played a crucial role and allowed deep glioma penetration depending on sequential intra-intercellular delivery via endocytosis-exocytosis. MSC-micelles were able to infiltrate from normal brain parenchyma towards contralateral tumors and led to the eradication of glioma. The survival of orthotopic glioma-bearing rats was significantly extended. In conclusion, the MSC-based delivery of HA-PLGA micelles is a potential strategy for tumor-targeting drug delivery.


Asunto(s)
Glioma , Células Madre Mesenquimatosas , Animales , Línea Celular Tumoral , Dioxanos , Portadores de Fármacos/uso terapéutico , Sistemas de Liberación de Medicamentos/métodos , Glioma/tratamiento farmacológico , Ácido Hialurónico/uso terapéutico , Micelas , Paclitaxel , Polímeros/uso terapéutico , Ratas
5.
Int J Mol Sci ; 22(12)2021 Jun 18.
Artículo en Inglés | MEDLINE | ID: mdl-34207287

RESUMEN

Gastrodia elata is a well-known medicinal and heterotrophic orchid. Its germination, limited by the impermeability of seed coat lignin and inhibition by abscisic acid (ABA), is triggered by symbiosis with fungi such as Mycena spp. However, the molecular mechanisms of lignin degradation by Mycena and ABA biosynthesis and signaling in G. elata remain unclear. In order to gain insights into these two processes, this study analyzed the transcriptomes of these organisms during their dynamic symbiosis. Among the 25 lignin-modifying enzyme genes in Mycena, two ligninolytic class II peroxidases and two laccases were significantly upregulated, most likely enabling Mycena hyphae to break through the lignin seed coats of G. elata. Genes related to reduced virulence and loss of pathogenicity in Mycena accounted for more than half of annotated genes, presumably contributing to symbiosis. After coculture, upregulated genes outnumbered downregulated genes in G. elata seeds, suggesting slightly increased biological activity, while Mycena hyphae had fewer upregulated than downregulated genes, indicating decreased biological activity. ABA biosynthesis in G. elata was reduced by the downregulated expression of 9-cis-epoxycarotenoid dioxygenase (NCED-2), and ABA signaling was blocked by the downregulated expression of a receptor protein (PYL12-like). This is the first report to describe the role of NCED-2 and PYL12-like in breaking G. elata seed dormancy by reducing the synthesis and blocking the signaling of the germination inhibitor ABA. This study provides a theoretical basis for screening germination fungi to identify effective symbionts and for reducing ABA inhibition of G. elata seed germination.


Asunto(s)
Ácido Abscísico/metabolismo , Agaricales/patogenicidad , Proteínas Fúngicas/genética , Gastrodia/microbiología , Lignina/metabolismo , Proteínas de Plantas/genética , Agaricales/genética , Agaricales/metabolismo , Dioxigenasas/genética , Dioxigenasas/metabolismo , Proteínas Fúngicas/metabolismo , Gastrodia/genética , Gastrodia/crecimiento & desarrollo , Gastrodia/metabolismo , Germinación , Lacasa/genética , Lacasa/metabolismo , Lignina/genética , Peroxidasas/genética , Peroxidasas/metabolismo , Proteínas de Plantas/metabolismo , Simbiosis , Transcriptoma
6.
J Fluoresc ; 30(6): 1365-1374, 2020 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-32897496

RESUMEN

Two new Zn(II)-based coordination polymers {[Zn3(L1)6(H2O)]∙(H2O)4}n (1, HL1 = 4-(tetrazol-5-yl)phenyl-4,2':6',4″-terpyridine) and [Zn2Cl2(L2)2H2O]n (2, HL2 = 4-([2,2':6',2″'-terpyridin]-4'-yl)benzoic acid) have been successfully prepared using two similar organic ligands with distinct donor groups under similar reaction conditions. The distinct structural features and donor atoms make the two complexes show different water stability, and the complex 1 with good water stability, which can be utilized as the sensor for Fe3+ ion detection in water. The value of Stern-Volmer quenching constant of 1 to the Fe3+ is 5.77 × 104 M- 1, which lies in the top region of the reported CP-based sensors. The mechanism investigation reveals that the energy transfer of resonance from the complex 1 to the Fe3+ ion can account for its fluorescent quenching behavior. The treatment activity of compounds 1 and 2 on the postpartum hemorrhage (PPH) was assessed. First, the cytotoxicity of compounds 1 and 2 on human umbilical vein endothelial cells was assessed with Cell Counting Kit-8 detection kit. Then, to evaluate the prevention of compounds 1 and 2 on the PPH, we conducted the Lowry method and detected the clotting factor IX and anticoagulant factor III contents after the indicated treatment. Finally, the inflammatory response in mice was determined by ELISA method, and the IL-6 and IL-8 levels were determined.


Asunto(s)
Anticoagulantes/química , Anticoagulantes/farmacología , Hierro/química , Polímeros/química , Hemorragia Posparto/prevención & control , Zinc/química , Ácido Benzoico/química , Estabilidad de Medicamentos , Fibrinógeno/metabolismo , Células Endoteliales de la Vena Umbilical Humana/efectos de los fármacos , Humanos , Interleucina-6/metabolismo , Interleucina-8/metabolismo , Ligandos , Hemorragia Posparto/metabolismo , Agua/química
7.
J Nanobiotechnology ; 18(1): 80, 2020 May 24.
Artículo en Inglés | MEDLINE | ID: mdl-32448273

RESUMEN

BACKGROUND: Psoriasis is a chronic immune-mediated inflammatory skin disease without effective treatment. The utilization of all trans-retinoic acid (TRA) and betamethasone (BT) for the treatment of psoriasis is still facing difficulties, due to their relatively poor stability, limited skin permeation, and systemic side effects. Flexible liposomes are excellent in deeper skin permeation and reducing the side effects of drugs, which is promising for effective treatment of skin disorders. This work aimed to establish dual-loaded flexible liposomal gel for enhanced therapeutic efficiency of psoriasis based on TRA and BT. RESULTS: Flexible liposomes co-loaded with TRA and BT were successfully prepared in our study. The characterization examination revealed that flexible liposomes featured nano-sized particles (around 70 nm), high drug encapsulation efficiency (> 98%) and sustained drug release behaviors. Flexible liposomes remarkably increased the drug skin permeation and retention as compared with free drugs. Results on HaCaT cells suggested that flexible liposomes were nontoxic, and its cellular uptake has a time-dependent manner. In vivo studies suggested the topical application of TRA and BT dual-loaded liposomal gel had the best ability to reduce the thickness of epidermal and the level of cytokines (TNF-α and IL-6), largely alleviating the symptoms of psoriasis. CONCLUSIONS: Flexible liposomal gel dual-loaded with TRA and BT exerted a synergistic effect, which is a promising topical therapeutic for the treatment of psoriasis.


Asunto(s)
Betametasona , Fármacos Dermatológicos , Liposomas , Psoriasis , Tretinoina , Animales , Betametasona/química , Betametasona/farmacocinética , Betametasona/farmacología , Supervivencia Celular/efectos de los fármacos , Citocinas/metabolismo , Fármacos Dermatológicos/química , Fármacos Dermatológicos/farmacocinética , Fármacos Dermatológicos/farmacología , Fármacos Dermatológicos/toxicidad , Modelos Animales de Enfermedad , Geles , Células HaCaT , Humanos , Liposomas/química , Liposomas/farmacocinética , Liposomas/farmacología , Liposomas/toxicidad , Ratones Endogámicos BALB C , Tamaño de la Partícula , Docilidad , Psoriasis/tratamiento farmacológico , Psoriasis/metabolismo , Ratas , Ratas Sprague-Dawley , Tretinoina/química , Tretinoina/farmacocinética , Tretinoina/farmacología
8.
Mol Pharm ; 16(11): 4530-4541, 2019 11 04.
Artículo en Inglés | MEDLINE | ID: mdl-31617723

RESUMEN

Tumor metastasis is the most dangerous stage in tumorigenesis and its evolution, which causes about 80% clinical death. However, common therapies including chemotherapy may increase the risk of tumor metastasis while killing cancer cells. Tumor metastasis is closely related to many factors in the tumor microenvironment, especially hypoxia. As one of the characteristics of a malignant tumor microenvironment, hypoxia plays an important role in the growth, metabolism, and metastasis of tumors. Upregulation of the hypoxia-inducible factor (HIF) would stimulate the metastasis and migration of cancer cells. In this study, we developed an artificial oxygen carrier system, a hemoglobin-loaded liposome (Hb@lipo), which was capable of effectively delivering oxygen to tumor. The way of providing oxygen not only alleviated tumor hypoxia but also downregulated the expression of HIF, which is conducive to reducing tumor malignancy. Alleviating the tumor hypoxic microenvironment alone is not enough to inhibit tumor metastasis; thus, we prepared the liposome containing a chemotherapeutic agent cabazitaxel (CBZ@lipo). Our data indicated that the combination therapy of Hb@lipo and CBZ@lipo can efficiently kill cancer cells and inhibit tumor growth. At the same time, it can effectively entrap cancer cells in tumor sites by relieving the hypoxic microenvironment of tumors and reduce the metastasis of cancer cells during and after the chemotherapy. Our research may provide a clinical cancer chemotherapy reference that reduces the risk of cancer cell metastasis while inhibiting tumor growth.


Asunto(s)
Antineoplásicos/farmacología , Metástasis de la Neoplasia/tratamiento farmacológico , Oxígeno/metabolismo , Hipoxia Tumoral/efectos de los fármacos , Animales , Biomimética/métodos , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Sistemas de Liberación de Medicamentos/métodos , Femenino , Células HT29 , Humanos , Subunidad alfa del Factor 1 Inducible por Hipoxia/metabolismo , Liposomas/química , Células MCF-7 , Melanoma Experimental , Ratones , Ratones Endogámicos BALB C , Microambiente Tumoral/efectos de los fármacos
9.
Clin Oral Investig ; 20(8): 1849-1859, 2016 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-26631059

RESUMEN

OBJECTIVES: This study aims to determine the effectiveness of a messaging app (WeChat) in improving patients' compliance and reducing the duration of orthodontic treatment (DOT). MATERIALS AND METHODS: A randomized controlled trial was performed in a dental hospital and a clinic from August 2012 to May 2015. Orthodontic patients were included at the beginning of treatment. Patients with multiphase treatment or braceless technique were excluded. Participants were randomized to WeChat group (received regular reminders and educational messages) or control group (received conventional management) and were followed up until the treatment was completed. Primary outcome measure was DOT. Others were late and failed attendance, bracket bond failure, and oral hygiene condition. RESULTS: One hundred twelve patients in each group participated and completed the trial. DOT in WeChat group were 7.3 weeks shorter (P = 0.007). There were less failed attendance (3.1 vs. 10.9 %, P < 0.001), late attendance (20.1 vs. 29.9 %, P < 0.001), and bracket bond failure (11.8 vs. 16.1 %, P < 0.001) in WeChat group than control. There was no difference in orthodontic plaque index nor modified gingivitis index between the two groups before and after treatment. Number of failed attendances was identified as an independent factor affecting DOT (P = 0.004; HR = 0.89, 95 % CI 0.84 to 0.95). CONCLUSIONS: The intervention with WeChat is effective in reducing the treatment duration and bracket bond failure, and improving the attendance in orthodontic patients. CLINICAL RELEVANCE: DOT can be reduced by improving patient's compliance. The messaging app is useful for outpatient education and management.


Asunto(s)
Aplicaciones Móviles , Ortodoncia Correctiva , Cooperación del Paciente , Adolescente , Adulto , China , Femenino , Humanos , Masculino , Factores de Tiempo
10.
J Med Virol ; 87(2): 256-62, 2015 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-25043151

RESUMEN

Enterovirus 71 (EV71) is an important agent responsible for hand-foot-and-mouth disease (HFMD), which can cause severe neurological complications and death in children. However, there is no specific treatment for EV71 infection, and a safe and effective vaccine is needed urgently. In this study, an effective and economical method for the production of EV71-VP1 protein was developed, and the VP1 protein was evaluated in humoral and cellular immune responses as an EV71 vaccine. The results revealed that the VP1 protein induced high titers of cross-neutralizing antibodies for different EV71 subtypes, and elicited significant splenocyte proliferation. The high levels of IFN-r and IL-10 showed the VP1 protein induced a mixed Th1 and Th2 immune response. Vaccinated female mice could confer protection in their neonatal offspring. Compared with the inactivated EV71, the VP1 protein elicited similar humoral and cellular responses, but the engineered protein is safer, less expensive and can be produced more efficiently. Therefore, EV71-VP1 protein can induce effective immunologic protection against EV71 and is an ideal candidate against EV71 infection.


Asunto(s)
Enterovirus Humano A/inmunología , Enfermedad de Boca, Mano y Pie/prevención & control , Proteínas Estructurales Virales/inmunología , Vacunas Virales/inmunología , Animales , Anticuerpos Neutralizantes/sangre , Anticuerpos Antivirales/sangre , Proliferación Celular , Citocinas/metabolismo , Modelos Animales de Enfermedad , Femenino , Enfermedad de Boca, Mano y Pie/inmunología , Inmunidad Materno-Adquirida , Leucocitos Mononucleares/inmunología , Ratones Endogámicos BALB C , Bazo/inmunología , Vacunas de Subunidad/administración & dosificación , Vacunas de Subunidad/inmunología , Vacunas de Subunidad/aislamiento & purificación , Vacunas Virales/administración & dosificación , Vacunas Virales/aislamiento & purificación
11.
Langmuir ; 31(21): 5851-8, 2015 Jun 02.
Artículo en Inglés | MEDLINE | ID: mdl-25966974

RESUMEN

Zwitterionic materials have received great attention because of the non-fouling property. As a result of the electric neutrality of zwitterionic polymers, their layer-by-layer (LBL) assembly is generally conducted under specific conditions, such as very low pH values or ionic strength. The formed multilayers are unstable at high pH or in a high ionic strength environment. Therefore, the formation of highly stable multilayers of zwitterionic polymers via the LBL assembly process is still challenging. Here, we report the LBL assembly of poly(sulfobetaine methacrylate) (PSBMA) with a polyphenol, tannic acid (TA), for protein-resistant surfaces. The assembly process was monitored by a quartz crystal microbalance (QCM) and variable-angle spectroscopic ellipsometry (VASE), which confirms the formation of thin multilayer films. We found that the (TA/PSBMA)n multilayers are stable over a wide pH range of 4-10 and in saline, such as 1 M NaCl or urea solution. The surface morphology and chemical composition were characterized by specular reflectance Fourier transform infrared spectroscopy (FTIR/SR), X-ray photoelectron spectroscopy (XPS), and atomic force microscopy (AFM). Furthermore, (TA/PSBMA)n multilayers show high hydrophilicity, with a water contact angle lower than 15°. A QCM was used to record the dynamic protein adsorption process. Adsorption amounts of bovine serum albumin (BSA), lysozyme (Lys), and hemoglobin (Hgb) on (TA/PSBMA)20 multilayers decreased to 0.42, 52.9, and 37.9 ng/cm(2) from 328, 357, and 509 ng/cm(2) on a bare gold chip surface, respectively. In addition, the protein-resistance property depends upon the outmost layer. This work provides new insights into the LBL assembly of zwitterionic polymers.


Asunto(s)
Metacrilatos/química , Taninos/química , Adsorción , Materiales Biocompatibles/química , Hemoglobinas/química , Microscopía de Fuerza Atómica , Muramidasa/química , Espectroscopía de Fotoelectrones , Tecnicas de Microbalanza del Cristal de Cuarzo , Albúmina Sérica Bovina/química , Espectroscopía Infrarroja por Transformada de Fourier , Propiedades de Superficie
12.
J Sep Sci ; 38(1): 81-6, 2015 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-25363498

RESUMEN

Surface-initiated atom transfer radical polymerization was successfully used to prepare 4-vinylphenylboronic acid functionalized poly(glycidylmethacrylate-co-ethylenedimethacrylate) beads for the selective enrichment of glycoprotein from complex biological samples in this study. The modified bead surfaces were characterized using Fourier transform infrared spectroscopy and X-ray photoelectron spectroscopy. The sorption behaviors, including adsorption isotherms, incubation time, and pH effect, were investigated. The results demonstrated that the boronated beads have a high affinity for glycoprotein, which is due to the well-defined boronic acid brushes on the beads surfaces. Furthermore, the polyvinylphenylboronic acid grafted poly(glycidylmethacrylate-co-ethylenedimethacrylate) beads were used to efficiently enrich and purify glycoprotein from real egg white samples and α-fetoprotein from human serum samples. The mass spectrometry results demonstrated that the polyvinylphenylboronic acid grafted poly(glycidylmethacrylate-co-ethylenedimethacrylate) beads are a suitable material for the enrichment of glycosylated protein from complex biological samples.


Asunto(s)
Métodos Analíticos de la Preparación de la Muestra/métodos , Glicoproteínas/aislamiento & purificación , Metilmetacrilatos/química , Polímeros/química , Adsorción , Animales , Ácidos Borónicos/química , Pollos , Clara de Huevo/química , Glicoproteínas/química , Humanos , Polimerizacion , Polímeros/síntesis química , alfa-Fetoproteínas/química , alfa-Fetoproteínas/aislamiento & purificación
13.
J Am Chem Soc ; 136(1): 157-63, 2014 Jan 08.
Artículo en Inglés | MEDLINE | ID: mdl-24283288

RESUMEN

Polymer vesicles formed by a pair of oppositely charged poly(ethylene glycol) (PEG)-based block aniomer and homocatiomer, termed "PICsomes", have tunable size, and are characterized by unique semipermeable property due to the flexible and tunable hydrophilicity of polyion complex (PIC) membranes. The PICsomes can encapsulate a variety of molecules in an inner aqueous phase just by a simple vortex mixing of solution, expecting their utility as nanocontainers of substances with biomedical interests. Here, we report on a new functionality of the PICsomes: photoinduced release of photoactive agents for intracellular drug delivery. A potent photosensitizer, Al(III) phthalocyanine chloride disulfonic acid (AlPcS2a), was efficiently incorporated into the PICsomes (11%(w/w)), and its quick release was induced by photoirradiation possibly due to the photochemical damage of the PIC membranes. The combination of a high-resolution fluorescent confocal microscopy and a lysosome membrane-specific staining method revealed that such photoinduced release of AlPcS2a occurred even in the lysosomes of living cells after endocytic internalization. Simultaneously, the released AlPcS2a photochemically affected the integrity of the lysosomal membranes, leading to the translocation of AlPcS2a and PICsomes themselves to the cytoplasm. Consequently, the AlPcS2a-encapsulated PICsomes (AlPcS2a-PICsomes) exhibited appreciably stronger photocytotoxicity compared with free AlPcS2a alone. Thus, the AlPcS2a-PICsomes have promising feasibility for the photodynamic therapy or the photoinduced cytoplasmic delivery of therapeutic molecules.


Asunto(s)
Complejos de Coordinación/química , Sistemas de Liberación de Medicamentos , Fármacos Fotosensibilizantes/química , Vesículas Transportadoras/química , Línea Celular Tumoral , Humanos , Microscopía Confocal , Imagen Óptica , Polietilenglicoles/química
14.
Fungal Genet Biol ; 65: 1-13, 2014 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-24503549

RESUMEN

Fusarium oxysporum f. sp. cubense (FOC) is the causal agent of banana Fusarium wilt and has become one of the most destructive pathogens threatening the banana production worldwide. However, few genes related to morphogenesis and pathogenicity of this fungal pathogen have been functionally characterized. In this study, we identified and characterized the disrupted gene in a T-DNA insertional mutant (L953) of FOC with significantly reduced virulence on banana plants. The gene disrupted by T-DNA insertion in L953 harbors an open reading frame, which encodes a protein with homology to α-1,6-mannosyltransferase (OCH1) in fungi. The deletion mutants (ΔFoOCH1) of the OCH1 orthologue (FoOCH1) in FOC were impaired in fungal growth, exhibited brighter staining with fluorescein isothiocyanate (FITC)-Concanavalin A, had less cell wall proteins and secreted more proteins into liquid media than the wild type. Furthermore, the mutation or deletion of FoOCH1 led to loss of ability to penetrate cellophane membrane and decline in hyphal attachment and colonization as well as virulence to the banana host. The mutant phenotypes were fully restored by complementation with the wild type FoOCH1 gene. Our data provide a first evidence for the critical role of FoOCH1 in maintenance of cell wall integrity and virulence of F. oxysporum f. sp. cubense.


Asunto(s)
Fusarium/metabolismo , Manosiltransferasas/metabolismo , Pared Celular/metabolismo , Celofán/química , ADN Bacteriano/genética , Fusarium/genética , Fusarium/patogenicidad , Hifa/genética , Hifa/metabolismo , Manosiltransferasas/genética , Musa/microbiología , Mutación , Filogenia , Raíces de Plantas/microbiología , Esporas Fúngicas/genética , Esporas Fúngicas/metabolismo , Virulencia
15.
Anal Bioanal Chem ; 406(28): 7221-31, 2014 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-25260404

RESUMEN

Thermal preparation of lysozyme-imprinted microspheres was firstly investigated by using biocompatible ionic liquid (IL) as a thermal stabilizer. The imprinted microspheres made with IL could obtain the good recognition ability to template protein, whereas the imprinted polymer synthesized in the absence of it had a similar adsorption capacity to the non-imprinted one. Furthermore, the preparation conditions of imprinted polymers (MIPs) including the content of IL, temperature of polymerization, and types of functional monomers and crosslinkers were systematically analyzed via circular dichroism spectrum and activity assay. The results illustrated that using hydroxyethyl acrylate as the functional monomer, ethylene glycol dimethacrylate as the crosslinker, 5 % IL as the stabilizer, and 75 °C as the reaction temperature could retain the structure of template protein as much as possible. The obtained MIPs showed excellent recognition ability to the template protein with the separation factor and selectivity factor value of 4.30 and 2.21, respectively. Consequently, it is an effective way to accurately imprint and separate template protein by cooperatively using circular dichroism spectroscopy and activity assay during the preparation of protein MIPs. The method of utilizing IL to stabilizing protein at high temperature would offer a good opportunity for various technologies to improve the development of macromolecules imprinting.


Asunto(s)
Líquidos Iónicos , Microesferas , Impresión Molecular , Muramidasa/química , Muramidasa/metabolismo , Animales , Pollos , Dicroismo Circular , Polímeros , Extracción en Fase Sólida , Temperatura
16.
Am J Orthod Dentofacial Orthop ; 146(4): 442-50, 2014 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-25263147

RESUMEN

INTRODUCTION: Midpalatal suture expansion could induce osteogenesis to correct maxillary insufficiency; cartilage formation could also be induced, and lower-magnitude forces might generate a preferable response pattern. In this study, we aimed for an enhanced understanding of the cartilage formatting effects of expansion. METHODS: Thirty 6-week-old male C57BL/6 mice were randomly and evenly assigned to 3 groups; the animals in each group received a sustained suture expansion at 0, 10, and 20 g, respectively. Ten additional mice were fed the same as the baseline controls and received no expansion. After 7 days, the animals were killed; coronal paraffin sections were stained using toluidine blue and safranin-O. The proliferating cell nucleus antigen, the nuclear antigen Ki-67, alkaline phosphatase, and matrix metalloproteinase 13 expressions were visualized with immunohistochemistry. All data were analyzed statistically, and the differences were considered significant at P <0.05. RESULTS: Compared with the control, the cartilage matrix volume was significantly increased by the 20-g expansion, showing increased cartilage matrix and hypertrophic chondrocytes with the highest matrix metalloproteinase 13 expression. The 10-g expansion formed condensed proliferating chondrocyte masses, within which the highest percentages of proliferating cell nucleus antigen and Ki-67 positive cells were present. The 10-g and the 20-g expansions equally intensified the alkaline phosphatase expression. CONCLUSIONS: The lower expansion (10 g) promoted chondrocyte proliferation and induced a more preferable suture cartilage response pattern compared with the higher expansion (20 g), which just increased the cartilage matrix production.


Asunto(s)
Cartílago/fisiología , Condrogénesis/fisiología , Suturas Craneales/fisiología , Técnica de Expansión Palatina , Hueso Paladar/fisiología , Fosfatasa Alcalina/análisis , Animales , Fenómenos Biomecánicos , Diferenciación Celular/fisiología , Proliferación Celular , Condrocitos/fisiología , Colorantes , Antígeno Ki-67/análisis , Masculino , Metaloproteinasa 13 de la Matriz/análisis , Ratones , Ratones Endogámicos C57BL , Ratones Endogámicos , Osteogénesis/fisiología , Fenazinas , Antígeno Nuclear de Célula en Proliferación/análisis , Distribución Aleatoria , Estrés Mecánico , Cloruro de Tolonio
17.
Zhejiang Da Xue Xue Bao Yi Xue Ban ; 43(2): 212-7, 2014 03.
Artículo en Zh | MEDLINE | ID: mdl-24782380

RESUMEN

OBJECTIVE: To investigate the epidemic characteristics of hand-foot-and-mouth disease (HFMD) in children and exposed population in Hangzhou city. METHODS: The throat swab or stool samples from children with HFMD admitted in Hangzhou Children's Hospital were collected. The HFMD pathogens were detected by real-time fluorescent quantitative PCR. The distribution of different HFMD pathogens in HFMD patients was subsequently determined. Human enteric virus type-71 (HEV71) in stool samples from subjects, who had close or general contact to 54 severe HFMD children with positive HEV71, was detected, and these contact persons were followed-up for one month. The diversity of predominant pathogens of HFMD in the area during 2011-2013 was investigated. RESULTS: In 641 HFMD children, the male/female ratio was 1.4:1 and 80.3% was 1-3 years old. HEV71 was detected in 24.3% HFMD children (156/641), while coxsackievirus group-A type-16 (CVA16) and other enteroviruses were detected in 4.7% (30/641) and 71.0% (455/641) of the cases, respectively. 75.6% (118/156) of HEV71-infected cases were diagnosed as severe HFMD cases, while those for CVA16-infected and other HFMD viruses-infected were 13.3% (4/30) and 6.2% (28/455) respectively (Χ(2)=43.28, P<0.05). HEV71 was the predominant HFMD pathogens during 2011-2012, while the predominant HFMD pathogens in 2013 were the other HFMD viruses. In the 54 close contact persons or 54 general contact persons, 9 or 10 persons were detectable for HEV71, but no clinical symptoms of HFMD were presented. CONCLUSION: There are no marked changes of epidemic seasons, favorable age and gender ratio of HFMD in Hangzhou area in 2013. The infection of HEV71 tends to cause the severe HFMD but the other enteroviruses have substituted HEV71 as the predominant pathogens of HFMD.


Asunto(s)
Enfermedad de Boca, Mano y Pie/epidemiología , Adolescente , Niño , Preescolar , China/epidemiología , Enterovirus Humano A/aislamiento & purificación , Femenino , Humanos , Lactante , Masculino
18.
J Hazard Mater ; 464: 132942, 2024 02 15.
Artículo en Inglés | MEDLINE | ID: mdl-37992502

RESUMEN

Microplastics can affect the physicochemical properties of soil and soil microorganisms, potentially resulting in changes in the soil sulfur mineralization and its capacity to supply available sulfur. However, the specific mechanisms underlying these effects remain unclear. We performed soil microcosm experiments, in which the effects of polystyrene (PS) and polyphenylene sulfide (PPS) microplastics on sulfur mineralization were examined in black, meadow, and paddy soils under flooded and dry conditions. Under dry condition, the presence of PS and PPS microplastics impeded sulfur (S) mineralization in black and paddy soils, but promoted sulfur mineralization in meadow soil. The size of microplastics was identified as the primary factor influencing sulfur mineralization in black soil, while in meadow soil, it was influenced by the microplastics type. In the case of paddy soil, the concentration of microplastics was the key factor affecting sulfur mineralization. During the flooding period, PS and PPS microplastics in black and paddy soils curtailed sulfur mineralization, however expedited sulfur mineralization in meadow soil, with PS enhancing soil sulfur mineralization more pronouncedly than PPS in black soil. The type and concentration of microplastics were identified as the main factors affecting sulfur mineralization in black soil, while in paddy soil, it was influenced by the size of microplastics. The principal regulating factors of soil sulfur mineralization were the sulphatase and arylsulfatase enzymes produced by Actinobacteria, Xanthomonadales, and Rhizobiales microorganisms, while organic matter and Olsen-P also had an influential role. Additionally, microplastics directly affected the structure of soil enzymes, thereby altering soil enzyme activities. This study provided insights into the mechanism by which microplastics affect soil sulfur mineralization, offering significant implications for assessing the influence of microplastics on soil sulfur availability and making informed decisions about sulfur application in future agricultural practices.


Asunto(s)
Oryza , Suelo , Suelo/química , Microplásticos , Plásticos , Azufre
19.
Int J Biol Macromol ; 278(Pt 2): 134697, 2024 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-39147352

RESUMEN

In this study, lignin derived from corncobs was chemically modified by substituting the hydroxyl groups present in its structure with methacrylate groups through a catalytic reaction using methacrylic anhydride, resulting in methacrylated lignin (ML). These MLs were incorporated in polymerization reaction of the monomer 2-[(acryloyloxy)ethyl trimethylammonium] chloride (Cl-AETA) and Cl-AETA, Cl-AETA/ML polymers were obtained, characterized (spectroscopic, thermal and microscopic analysis), and evaluated for removing Cr (VI) and As (V) from aqueous media in function of pH, contact time, initial metal concentrations and adsorbent amount. The Cl-AETA/ML polymers followed the Langmuir adsorption model for the evaluated metal anions and were able to remove up to 91 % of Cr (VI) with a qmax (maximum adsorption capacity) of 201 mg/g, while for As (V), up to 60 % could be removed with a qmax of 58 mg/g. The results demonstrate that simple modifications in lignin enhance its functionalization and properties, making it suitable for removing contaminants from aqueous media, showing promising results for potential future applications.


Asunto(s)
Cromo , Lignina , Contaminantes Químicos del Agua , Lignina/química , Cromo/química , Cromo/aislamiento & purificación , Adsorción , Contaminantes Químicos del Agua/química , Contaminantes Químicos del Agua/aislamiento & purificación , Purificación del Agua/métodos , Polímeros/química , Polímeros/síntesis química , Agua/química , Concentración de Iones de Hidrógeno , Polimerizacion
20.
J Hazard Mater ; 465: 133432, 2024 Mar 05.
Artículo en Inglés | MEDLINE | ID: mdl-38219596

RESUMEN

Microplastics can potentially affect the physical and chemical properties of soil, as well as soil microbial communities. This could, in turn, influence soil sulfur REDOX processes and the ability of soil to supply sulfur effectively. However, the specific mechanisms driving these effects remain unclear. To explore this, soil microcosm experiments were conducted to assess the impacts of polystyrene (PS) and polyphenylene sulfide (PPS) microplastics on sulfur reduction-oxidation (REDOX) processes in black, meadow, and paddy soils. The findings revealed that PS and PPS most significantly decreased SO42- in black soil by 9.4%, elevated SO42- in meadow soil by 20.8%, and increased S2- in paddy soil by 20.5%. PS and PPS microplastics impacted the oxidation process of sulfur in soil by influencing the activity of sulfur dioxygenase, which was mediated by α-proteobacteria and γ-proteobacteria, and the oxidation process was negatively influenced by soil organic matter. PS and PPS microplastics impacted the reduction process of sulfur in soil by influencing the activity of adenosine-5'-phosphosulfate reductase, sulfite reductase, which was mediated by Desulfuromonadales and Desulfarculales, and the reduction process was positively influenced by soil organic matter. In addition to their impacts on microorganisms, it was found that PP and PPS microplastics directly influenced the structure of soil enzymes, leading to alterations in soil enzyme activity. This study sheds light on the mechanisms by which microplastics impact soil sulfur REDOX processes, providing valuable insights into how microplastics influence soil health and functioning, which is essential for optimizing crop growth and maximizing yield in future agricultural practices.


Asunto(s)
Microplásticos , Suelo , Plásticos , Agricultura , Poliestirenos , Azufre
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