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1.
Nanotechnology ; 35(34)2024 Jun 07.
Artículo en Inglés | MEDLINE | ID: mdl-38788695

RESUMEN

Although chlorambucil (CHL) is a long-established anticancer drug, the drug failure of CHL, mediated by the intracellular defense system consisting of glutathione (GSH) and GSH S-transferase pi (GST-pi), has significantly limited the application of CHL. To overcome this issue, we first designed a GSH-responsive small-molecule prodrug (EA-SS-CHL) by combining CHL and ethacrynic acid (EA). Subsequently, drug-loaded nanoparticles (ECPP) were formed by the self-assembly between EA-SS-CHL and amphiphilic PEG-PDLLA to improve the water solubility of the prodrug and its ability to target tumor sites. Upon exposure to high intracellular GSH concentration, EA-SS-CHL gradually degrades, leading to the release of EA and CHL. The presence of EA facilitates the depletion of GSH and inhibition of GST-pi, ultimately attenuating the detoxification of the intracellular defense system to CHL. Cytotoxicity studies and apoptosis assays demonstrate that ECPP exhibits higher therapeutic efficiency than CHL. Additionally,in vivotumor suppression effects and biocompatibility provide further evidence for the superiority of ECPP. This work presents a promising strategy to enhance the efficacy of CHL in cancer therapy.


Asunto(s)
Clorambucilo , Ácido Etacrínico , Glutatión , Micelas , Profármacos , Clorambucilo/farmacología , Clorambucilo/química , Profármacos/farmacología , Profármacos/química , Glutatión/metabolismo , Humanos , Animales , Ácido Etacrínico/farmacología , Ácido Etacrínico/química , Nanopartículas/química , Ratones , Gutatión-S-Transferasa pi/metabolismo , Gutatión-S-Transferasa pi/antagonistas & inhibidores , Apoptosis/efectos de los fármacos , Línea Celular Tumoral , Antineoplásicos/farmacología , Antineoplásicos/química , Polietilenglicoles/química , Glutatión Transferasa/metabolismo , Portadores de Fármacos/química , Liberación de Fármacos
2.
Environ Res ; 248: 118263, 2024 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-38281564

RESUMEN

With the increase of sustainable development goal, the bio-based adsorption materials with high and selective dye removal are important for water treatment in the dyeing industry. In this paper, a bio-based adsorption foam composed of metal-organic frameworks (MOF) and polyethyleneimine (PEI)-modified cellulose was prepared by a three-step process, i.e., PEI modification of cellulose fibers (PC), MOF decoration of PEI-modified cellulose (MIL-53@PC), and in-situ foaming with polyurethane. PEI modification provides cellulose fiber with more active sites for both dye adsorption and MOF bonding. We found that MIL-53 crystals were tightly bonded on the surface of PC through hydrogen bonding. Because of the abundant adsorption sites (e.g., amines, iron oxide group), the MIL-53@PC demonstrated high adsorption capacity and selectivity for anionic dye (e.g., 936.5 mg/g for methyl orange) through electrostatic interaction and hydrogen bonding. Finally, MIL-53@PC particles were blended with a waterborne polyurethane prepolymer to prepare a three-dimensional hydrophilic foam (MIL-53@PC/PUF), which not only maintained high adsorption capacity and selectivity of MIL-53@PC and also improved its recyclability and reusability. The MIL-53@PC/PUF offers a promising solution for dye wastewater treatment.


Asunto(s)
Celulosa/análogos & derivados , Estructuras Metalorgánicas , Polietileneimina/análogos & derivados , Contaminantes Químicos del Agua , Colorantes/química , Adsorción , Polietileneimina/química , Poliuretanos , Contaminantes Químicos del Agua/química
3.
Eur J Orthod ; 46(1)2024 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-38168816

RESUMEN

BACKGROUND: Agenesis of third molar agenesis has a higher incidence than other tooth development anomalies. Previous research identified a potential correlation between third molar agenesis and specific craniofacial morphology; however, no systematic review and meta-analysis on this topic currently exists. OBJECTIVE: The objective of this systematic review and meta-analysis was to evaluate the association between third molar agenesis and craniofacial sagittal and vertical morphology. SEARCH METHODS: An electronic search was conducted on PubMed, Embase, Web of Science, and the Cochrane Library without restrictions on publication year or language; this was supplemented by the manual retrieval of relevant literature. SELECTION CRITERIA: Cross-sectional studies that compared craniofacial morphology using angular and linear measurements obtained from lateral cephalography between patients with third molar agenesis and those without were included. DATA COLLECTION AND ANALYSIS: The quality assessment of the enrolled articles was evaluated by the Joanna Briggs Institute critical appraisal tool. Meta-analysis and sensitivity analysis were performed by Review Manager software (The Cochrane Collaborative, version 5.4, Cochrane IMS). RESULTS: A total of seven studies were included. Meta-analysis demonstrated that the ANB (mean differences (MD) = -0.75, 95% CI: -1.31 to -0.19, P < 0.01), palate length (ANS-PNS, MD = -1.68, 95% CI: -2.24 to -1.11, P < 0.01), and mandibular length (Go-Pog, MD = -0.36, 95% CI: -0.59 to -0.13, P < 0.01) were smaller in patients with third molar agenesis. With regard to vertical craniofacial morphology, the mandibular plane angle (MP-FH; MD = -1.88, 95% CI: -3.45 to -0.31, P = 0.02), gonial angle (gonial angle; MD = -1.73, 95% CI: -2.69 to -0.77, P < 0.01) and lower face height (lower face heigh angle; MD = -1.36, 95% CI: -1.94 to -0.77, P < 0.01) were smaller in patients with third molar agenesis, indicating a flatter or brachyfacial skeletal pattern. CONCLUSIONS: The results of this study suggest that third molar agenesis maybe associated with a reduced maxillary length and a flatter mandible. However, these findings need to be interpreted with caution due to inconsistencies in the certainty of evidence. CLINICAL TRIAL REGISTRATION: PROSPERO (CRD42023448226).


Asunto(s)
Maxilar , Tercer Molar , Humanos , Tercer Molar/diagnóstico por imagen , Tercer Molar/anomalías , Estudios Transversales , Mandíbula , Hueso Paladar
4.
Anal Chem ; 95(48): 17834-17842, 2023 12 05.
Artículo en Inglés | MEDLINE | ID: mdl-37988125

RESUMEN

Precise and sensitive analysis of exosomal microRNA (miRNA) is of great importance for noninvasive early disease diagnosis, but it remains a great challenge to detect exosomal miRNA in human blood samples because of their small size, high sequence homology, and low abundance. Herein, we integrated reliable Pt-S bond-mediated three-dimensional (3D) DNA nanomachine and magnetic separation in a homogeneous electrochemical strategy for the detection of exosomal miRNA with low background and high sensitivity. The 3D DNA nanomachine was easily prepared via a facile and rapid freezing method, and it was capable of resisting the influence of biothiols, thus endowing it with high stability. Notably, the as-developed magnetic 3D DNA nanomachine not only enabled the detection system to have a low background but also coupled with liposome nanocarriers to synergistically amplify the current signal. Consequently, by ingeniously combining the low background and multiple signal-amplification strategies in homogeneous electrochemical biosensing, highly sensitive detection of exosomal miRNA was successfully achieved. More significantly, with good anti-interference ability, the as-proposed method could effectively discriminate plasma samples from cancer patients and healthy subjects, thus showing a high potential for application in the nondestructive early clinical diagnosis of disease.


Asunto(s)
Técnicas Biosensibles , MicroARNs , Humanos , MicroARNs/análisis , ADN/análisis , Liposomas , Fenómenos Físicos , Fenómenos Magnéticos , Técnicas Biosensibles/métodos , Técnicas Electroquímicas/métodos , Límite de Detección
5.
J Craniofac Surg ; 34(8): 2417-2421, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37682000

RESUMEN

BACKGROUND: A crooked nose is an external nose deformity predominantly caused by congenital aplasia or acquired secondary to trauma or surgery, often accompanied by a deviated nasal septum. Patients with crooked nose have dual needs to improve both esthetic and functional problems. METHODS: The clinical and photographic information of 48 patients diagnosed with a crooked nose and nasal septum deviation treated from January 2018 to January 2022 was acquired. The morphology and functional effects were investigated by evaluating the general condition of the operation, measuring the esthetic indexes of the nose, and subjectively scoring. RESULTS: For both morphology and function, endoscopy-assisted one-stage correction showed positive results in this study. The external nose deviation distance postoperatively measured 1.28 (0.85, 1.97) mm, which significantly decreased from the preoperative value of 3.96 (3.31, 5.29) mm. The scores of doctors and irrelevant medical students on nose morphology increased significantly from 4.75±1.88 and 3.84±0.76 to 6.48±1.21 and 7.21±0.67, respectively. The rhinoplasty outcome evaluation score and the "nasal obstruction symptom evaluation "score of patients were both significantly improved ( t = -7.508 and t =6.310, respectively, P < 0.001). CONCLUSION: Endoscope-assisted one-stage correction of the crooked nose can restore nasal morphology, improve the symptoms of nasal obstruction, and achieve patient satisfaction. It is a minimally invasive, safe, effective, and fast recovery approach for patients who need to solve both esthetic and functional problems.


Asunto(s)
Obstrucción Nasal , Deformidades Adquiridas Nasales , Rinoplastia , Humanos , Tabique Nasal/cirugía , Tabique Nasal/anomalías , Obstrucción Nasal/cirugía , Deformidades Adquiridas Nasales/cirugía , Deformidades Adquiridas Nasales/complicaciones , Estética Dental , Nariz/cirugía , Nariz/anomalías , Rinoplastia/métodos , Resultado del Tratamiento
6.
J Prosthet Dent ; 130(4): 614-619, 2023 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-34973835

RESUMEN

STATEMENT OF PROBLEM: Race and sex differences in the mathematical proportions of maxillary anterior teeth have been evaluated. However, studies exploring the relationship between the mathematical proportion of maxillary anterior teeth and maxillary dental arch form are lacking. PURPOSE: The purpose of this clinical study was to determine if a correlation exists between the mathematical proportions of maxillary anterior teeth and 3 dental arch forms. MATERIAL AND METHODS: Three hundred young participants were recruited according to predefined criteria, and images and maxillary casts were obtained. The perceived width and length of the maxillary anterior teeth were measured on the images by using a software program, and mathematical proportions, including width ratios and width-to-length ratios, were calculated for each. The casts were used to categorize each specimen into tapered, ovoid, or square groups by using a specific classification method, and the width ratios and width-to-height ratios of the 3 dental arch forms were compared. Statistical analysis was performed by using analysis of variance (ANOVA) or the Kruskal-Wallis H test to compare the mathematical proportions of maxillary anterior teeth among the 3 dental arch forms (α=.05). The intraclass correlation coefficient (ICC) was used to test the reliability of the investigators. RESULTS: Except for the width-to-length ratios of the central incisor, mathematical proportions were affected by the dental arch form. The perceived width ratios of the maxillary lateral incisor-to-central incisor gradually increased from the tapered arch to the ovoid arch and from the ovoid arch to the square arch, with mean ±standard deviation values of 0.71 ±0.04, 0.73 ±0.05, and 0.79 ±0.06, respectively. For the maxillary perceived width ratios of canine-to-lateral incisor, the ovoid arch had the maximum perceived width ratios (0.86 ±0.10), followed by the tapered (0.82 ±0.10) and square arches (0.77 ±0.11). The width-to-length ratios of the central incisor were not affected by the arch form (P=.075), and the width-to-length ratios of the lateral incisor increased as the arch form became flat, with respective values of 0.70 ±0.10, 0.74 ±0.10, and 0.76 ±0.10. For the width-to-length ratios of the canine, the ovoid arch had the maximum perceived width ratios (0.58 ±0.10), followed by the tapered (0.53 ±0.10) and square arches (0.52 ±0.10). CONCLUSIONS: The mathematical proportions varied among the 3 dental arch forms, and the dental arch form should be considered during the prosthodontic design of maxillary anterior teeth.

7.
Molecules ; 28(10)2023 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-37241829

RESUMEN

The molecular weight of lignin extracted from lignocellulosic biomass is an important factor in determining its valorization in industrial processes. Herein, this work aims to explore the extraction of high molecular weight and bioactive lignin from water chestnut shells under mild conditions. Five kinds of deep eutectic solvents were prepared and applied to isolate lignin from water chestnut shells. The extracted lignin was further characterized with element analysis, gel permeation chromatography, and Ultraviolet-visible and Fourier-transform infrared spectroscopy. The distribution of pyrolysis products was identified and quantified with thermogravimetric analysis-Fourier-transform infrared spectroscopy and pyrolysis-gas chromatograph-mass spectrometry. The results showed that choline chloride/ethylene glycol/p-toluenesulfonic acid (1:1.8:0.2 molar ratio) exhibited the highest fractionation efficiency for lignin (84.17% yield) at 100 °C for 2 h. Simultaneously, the lignin showed high purity (90.4%), high relative molecular weight (37,077 g/mol), and excellent uniformity. Furthermore, the aromatic ring structure of lignin remained intact, consisting mainly of p-hydroxyphenyl, syringl, and guaiacyl subunits. The lignin generated a large number of volatile organic compounds during the depolymerization process, mainly composed of ketones, phenols, syringols, guaiacols, esters, and aromatic compounds. Finally, the antioxidant activity of the lignin sample was evaluated with the 1,1-diphenyl-2-picrylhydrazyl radical scavenging assay; the lignin from water chestnut shells showed excellent antioxidant activity. These findings confirm that lignin from water chestnut shells has a broad application prospect in valuable chemicals, biofuels and bio-functional materials.


Asunto(s)
Eleocharis , Lignina , Lignina/química , Antioxidantes , Disolventes Eutécticos Profundos , Pirólisis , Solventes/química , Biomasa
8.
Small ; 18(3): e2104993, 2022 01.
Artículo en Inglés | MEDLINE | ID: mdl-34837456

RESUMEN

Metal-free carbon nanozymes could be promising with the unique features of intrinsic catalytic ability, structure diversity, and strong tolerance to acidic/alkaline media. However, to date, the study of metal-free carbon nanozymes fell far behind metal-based nanomaterials, in which, the majority reported much more peroxidase-like activity than other enzyme-mimicking behavior (e.g., oxidase). Thus, the exploit of high-performance carbon nanozymes is of importance but challenging. In this work, the nitrogen-rich conjugated polymer (Aza-CPs) with rigid network structure is utilized as precursor to yield N-doped carbon material QAU-Z1 in high yield via a direct pyrolysis method. Surprisingly, QAU-Z1 stood out in oxidase-like behavior, which significantly outperformed the control materials GNC-900 and QAU-Z2 with nucleobase or conjugated small molecule as precursor, respectively. More importantly, it is a crucial revelation that the catalytic performance is closely related to the change of zeta potential for carbon nanozyme during the substrate 3,3',5,5'-tetramethylbenzidine oxidation process, as well as its catalytical capacity to O2 , which could be insightful to understand the inherent mechanism. This work not only presents the potential of conjugated polymers in constructing highly efficient carbon nanozyme, but also reveals the vital role of interaction mode between the nanozyme and substrate in the catalytic performance.


Asunto(s)
Carbono , Nanoestructuras , Carbono/química , Catálisis , Nitrógeno/química , Oxidorreductasas , Polímeros
9.
J Virol ; 95(15): e0036121, 2021 07 12.
Artículo en Inglés | MEDLINE | ID: mdl-33980594

RESUMEN

Foot-and-mouth disease virus (FMDV) is the pathogen of foot-and-mouth disease (FMD), which is a highly contagious disease in cloven-hoofed animals. To survive in the host, FMDV has evolved multiple strategies to antagonize host innate immune responses. In this study, we showed that the leader protease (Lpro) of FMDV, a papain-like proteinase, promoted viral replication by evading the antiviral interferon response through counteracting the 2',5'-oligoadenylate synthetase (OAS)/RNase L system. Specifically, we observed that the titers of Lpro deletion virus were significantly lower than those of wild-type FMDV (FMDV-WT) in cultured cells. Our mechanistic studies demonstrated that Lpro interfered with the OAS/RNase L pathway by interacting with the N-terminal domain of swine RNase L (sRNase L). Remarkably, Lpro of FMDV exhibited species-specific binding to RNase L in that the interaction was observed only in swine cells, not human, monkey, or canine cells. Lastly, we presented evidence that by interacting with sRNase L, FMDV Lpro inhibited cellular apoptosis. Taken together, these results demonstrate a novel mechanism that Lpro utilizes to escape the OAS/RNase L-mediated antiviral defense pathway. IMPORTANCE FMDV is a picornavirus that causes a significant disease in agricultural animals. FMDV has developed diverse strategies to escape the host interferon response. Here, we show that Lpro of FMDV antagonizes the OAS/RNase L pathway, an important interferon effector pathway, by interacting with the N-terminal domain of sRNase L. Interestingly, such a virus-host interaction is species-specific because the interaction is detected only in swine cells, not in human, monkey, or canine cells. Furthermore, Lpro inhibits apoptosis through interacting with sRNase L. This study demonstrates a novel mechanism by which FMDV has evolved to inhibit host innate immune responses.


Asunto(s)
2',5'-Oligoadenilato Sintetasa/metabolismo , Endopeptidasas/metabolismo , Endorribonucleasas/metabolismo , Virus de la Fiebre Aftosa/inmunología , Evasión Inmune/inmunología , Inmunidad Innata/inmunología , Animales , Apoptosis/inmunología , Línea Celular , Cricetinae , Perros , Endopeptidasas/genética , Endopeptidasas/inmunología , Endorribonucleasas/genética , Fiebre Aftosa/inmunología , Fiebre Aftosa/virología , Células HEK293 , Haplorrinos , Humanos , Evasión Inmune/genética , Células de Riñón Canino Madin Darby , Dominios Proteicos , Porcinos
10.
BMC Geriatr ; 22(1): 614, 2022 07 25.
Artículo en Inglés | MEDLINE | ID: mdl-35879659

RESUMEN

OBJECTIVES: To evaluate dentition status amongst community-dwelling older adults and its association with frailty and cognitive impairment. METHODOLOGY: One thousand forty-seven community-dwelling older adults aged ≥65 years were surveyed in an epidemiologic population-based cohort study in Singapore between April 2015 and August 2016. Data on demographics, dentition status, chronic diseases, activities and instrumental activities on daily-living, cognition (age- and education-specific MMSE cut-offs), frailty (FRAIL scale), perceived health and functional status were collected. Multiple logistic regression was performed to examine the association between dentition, frailty and cognition. RESULTS: Mean age of participants was 71.2 ± 5.5 years. The prevalence of denture use was 70.7% and edentulism 7.9%. Compared to edentulousness, having teeth was associated with lower odds of cognitive impairment and higher odds of being robust or pre-frail. Denture-wearers compared with edentulous persons were less likely to be male, had higher education level and more likely be robust or pre-frail. CONCLUSION AND IMPLICATIONS: There were significant associations between dentition status, frailty and cognition in our study where those with remining teeth and / or dentures had better overall outcomes. As oral health, frailty and cognitive impairments are all modifiable risk factors for healthy ageing, countries should consider population level screening for oral health, frailty and cognitive impairment.


Asunto(s)
Disfunción Cognitiva , Fragilidad , Anciano , Cognición , Disfunción Cognitiva/diagnóstico , Disfunción Cognitiva/epidemiología , Estudios de Cohortes , Estudios Transversales , Dentición , Femenino , Anciano Frágil/psicología , Fragilidad/diagnóstico , Evaluación Geriátrica , Humanos , Vida Independiente , Masculino
11.
Nano Lett ; 21(12): 5377-5385, 2021 06 23.
Artículo en Inglés | MEDLINE | ID: mdl-34100622

RESUMEN

DNAzyme is emerging for gene therapy. The administration of the in vivo catalytic activity of DNAzyme has proven important but challenging for clinical applications. Herein, we report a synergistic DNA-polydopamine-MnO2 nanocomplex, which enables near-infrared (NIR)-light-powered catalytic activity of DNAzyme in vivo. The nanocomplex has a hierarchical structure: a DNA nanoframework as the scaffold and polydopamine-MnO2 (PM) as the coating layer. The DNA nanoframework contains repeated DNAzyme sequences. PM assembles on the surface of the DNA nanoframework. When the nanocomplex accumulates at tumor sites, upon NIR-light radiation, polydopamine induces a temperature elevation at tumor sites via photothermal conversion; meanwhile, glutathione triggers decomposition of PM to release Mn2+ to activate DNAzyme in the cytoplasm for gene regulation. In vitro and in vivo experiments show that the PM-induced temperature elevation enhances the Egr-1 mRNA cleavage activity of DNAzyme, promoting downregulation of the Egr-1 protein in tumor cells. In addition, the temperature elevation induces heat stress, achieving a synergistic tumor ablation effect.


Asunto(s)
ADN Catalítico , ADN Catalítico/genética , Terapia Genética , Indoles , Fototerapia , Polímeros
12.
Int J Mol Sci ; 23(9)2022 May 09.
Artículo en Inglés | MEDLINE | ID: mdl-35563647

RESUMEN

Fatigue and other deleterious mood alterations resulting from prolonged efforts such as a long work shift can lead to a decrease in vigilance and cognitive performance, increasing the likelihood of errors during the execution of attention-demanding activities such as piloting an aircraft or performing medical procedures. Thus, a method to rapidly and objectively assess the risk for such cognitive fatigue would be of value. The objective of the study was the identification in saliva-borne exosomes of molecular signals associated with changes in mood and fatigue that may increase the risk of reduced cognitive performance. Using integrated multiomics analysis of exosomes from the saliva of medical residents before and after a 12 h work shift, we observed changes in the abundances of several proteins and miRNAs that were associated with various mood states, and specifically fatigue, as determined by a Profile of Mood States questionnaire. The findings herein point to a promising protein biomarker, phosphoglycerate kinase 1 (PGK1), that was associated with fatigue and displayed changes in abundance in saliva, and we suggest a possible biological mechanism whereby the expression of the PGK1 gene is regulated by miR3185 in response to fatigue. Overall, these data suggest that multiomics analysis of salivary exosomes has merit for identifying novel biomarkers associated with changes in mood states and fatigue. The promising biomarker protein presents an opportunity for the development of a rapid saliva-based test for the assessment of these changes.


Asunto(s)
Exosomas , MicroARNs , Biomarcadores/metabolismo , Exosomas/genética , Exosomas/metabolismo , MicroARNs/metabolismo , Saliva/metabolismo
13.
J Nanobiotechnology ; 19(1): 328, 2021 Oct 18.
Artículo en Inglés | MEDLINE | ID: mdl-34663354

RESUMEN

The tumor immune microenvironment (TIME) has been demonstrated to be the main cause of cancer immunotherapy failure in various malignant tumors, due to poor immunogenicity and existence of immunosuppressive factors. Thus, establishing effective treatments for hostile TIME remodeling has considerable potential to enhance immune response rates for durable tumor growth retardation. This study aims to develop a novel nanocomposite, polyethyleneimine-modified dendritic mesoporous silica nanoparticles loaded with microRNA-125a (DMSN-PEI@125a) to synergistically enhance immune response and immunosuppression reversion, ultimately generating a tumoricidal environment. Our results showed that DMSN-PEI@125a exhibited excellent ability in cellular uptake by murine macrophages and the cervical cancer cell line TC-1, repolarization of tumor associated macrophages (TAMs) to M1 type in a synergistic manner, and promotion of TC-1 immunogenic death. Intratumor injection of DMSN-PEI@125a facilitated the release of more damage-related molecular patterns and enhanced the infiltration of natural killer and CD8+ T cells. Meanwhile, repolarized TAMs could function as a helper to promote antitumor immunity, thus inhibiting tumor growth in TC-1 mouse models in a collaborative manner. Collectively, this work highlights the multifunctional roles of DMSN-PEI@125a in generating an inflammatory TIME and provoking antitumor immunity, which may serve as a potential agent for cancer immunotherapy.


Asunto(s)
Antineoplásicos , Nanocompuestos/química , Dióxido de Silicio , Microambiente Tumoral , Animales , Antineoplásicos/química , Antineoplásicos/farmacología , Apoptosis/efectos de los fármacos , Línea Celular Tumoral , Supervivencia Celular/efectos de los fármacos , Femenino , Inmunoterapia , Macrófagos/inmunología , Macrófagos/metabolismo , Ratones , Ratones Endogámicos C57BL , MicroARNs/química , MicroARNs/farmacología , Sistema de Administración de Fármacos con Nanopartículas , Polietileneimina/química , Dióxido de Silicio/química , Dióxido de Silicio/farmacología , Microambiente Tumoral/efectos de los fármacos , Microambiente Tumoral/inmunología
14.
Plant Dis ; 2020 Oct 19.
Artículo en Inglés | MEDLINE | ID: mdl-33074068

RESUMEN

Radix pseudostellariae L. is one of the most common and highly-prized Chinese medicinal plants with various pharmacological effects, and mainly produced in acid soils in the Guizhou and Fujian provinces of southwestern and southeastern China, respectively (Wu et al. 2020). However, consecutive monoculture of R. pseudostellariae results in severe root rot and decline in biomass and quality of underground tubers. Root tubers of R. pseudostellariae are typically planted in December and harvested in next June. Root rot commonly starts developing in May. The disease incidence of root rot was ranging from 37 to 46% in root portions and basal stem of R. pseudostellariae under the consecutive monoculture fields in Shibing County, Guizhou Province, China (108°12'E, 27°03'N) (Li et al. 2017). Severe root rot was observed in Shibing County in May 2018. Infected plants displayed curly, withered, and yellow leaves, blight, retarded growth, root rot, and yield losses. Abundant whitish mycelia were observed on roots and surrounding soil. Two fungal isolates, designated GZ20190123 and GZ20190124, were obtained from symptomatic roots cultured on potato dextrose agar (PDA). The optimum temperature range for growth of the two isolates was 25 to 30°C. The optimum pH range for the growth of GZ20190123 was 5 to 5.5, whereas GZ20190124 grew better between pH 5 to 8.5. The mean mycelial growth rates of GZ20190123 and GZ20190124 at 30°C were 2.1 and 1.5 cm/day, respectively. Conidia of the two isolates were ovoid or obclavate and were produced in single or branched chains. The internal transcribed spacer (ITS) region was amplified with primers ITS1 and ITS4 (White et al. 1990). The sequences were deposited in GenBank as accession No. MN726736 for GZ20190123 and MN726738 for GZ20190124. Sequence comparison revealed 99% (GZ20190123) and 97% (GZ20190124) identity with previously reported isolate xsd08071 of Mucor racemosus Bull. (accession No. FJ582639.1) and isolate BM3 of Mucor fragilis Bainier (accession No. MK910058.1), respectively, which was confirmed by phylogenetic analysis. The two isolates were tested for pathogenicity on R. pseudostellariae. Six roots of R. pseudostellariae were surface-sterilized with 75% ethanol and stab inoculated with mycelia using a sterile toothpick for each isolate. Sterile distilled water was stab inoculated to twelve roots to serve as the control. Treated roots were incubated in a greenhouse with 16 h day length [light intensity 146.5 µmol/(m2·s)] and day/night temperature 26°C/18°C. The inoculated roots showed the expected symptoms on roots and sprouts 7 days after inoculation, whereas the control roots with sprouts did not show any symptom. The fungi were re-isolated from the diseased roots and confirmed as expected M. racemosus or M. fragilis based on the ITS sequences, which satisfied Koch's postulates. Thus, isolate GZ20190123 was identified as M. racemosus and GZ20190124 as M. fragilis. Previously, M. racemosus and M. fragilis have been reported as a pathogen on tomato (Kwon and Hong 2005) and grape (Ghuffar et al. 2018), respectively. To our knowledge, this is the first report of M. racemosus and M. fragilis causing root rot of R. pseudostellariae in southwestern China, where the disease could cause a significant loss to production of this important medicinal plant.

15.
Angew Chem Int Ed Engl ; 59(18): 7224-7229, 2020 04 27.
Artículo en Inglés | MEDLINE | ID: mdl-32065712

RESUMEN

An organic semiconductor-bacteria biohybrid photosynthetic system is used to efficiently realize CO2 reduction to produce acetic acid with the non-photosynthetic bacteria Moorella thermoacetica. Perylene diimide derivative (PDI) and poly(fluorene-co-phenylene) (PFP) were coated on the bacteria surface as photosensitizers to form a p-n heterojunction (PFP/PDI) layer, affording higher hole/electron separation efficiency. The π-conjugated semiconductors possess excellent light-harvesting ability and biocompatibility, and the cationic side chains of organic semiconductors could intercalate into cell membranes, ensuring efficient electron transfer to bacteria. Moorella thermoacetica can thus harvest photoexcited electrons from the PFP/PDI heterojunction, driving the Wood-Ljungdahl pathway to synthesize acetic acid from CO2 under illumination. The efficiency of this organic biohybrid is about 1.6 %, which is comparable to those of reported inorganic biohybrid systems.


Asunto(s)
Ácido Acético/metabolismo , Dióxido de Carbono/metabolismo , Moorella/metabolismo , Fármacos Fotosensibilizantes/metabolismo , Energía Solar , Ácido Acético/química , Dióxido de Carbono/química , Transporte de Electrón , Fluorenos/química , Fluorenos/metabolismo , Imidas/química , Imidas/metabolismo , Estructura Molecular , Moorella/citología , Oxidación-Reducción , Perileno/análogos & derivados , Perileno/química , Perileno/metabolismo , Fármacos Fotosensibilizantes/química , Polímeros/química , Polímeros/metabolismo , Semiconductores , Propiedades de Superficie
16.
J Am Chem Soc ; 141(2): 794-799, 2019 01 16.
Artículo en Inglés | MEDLINE | ID: mdl-30588805

RESUMEN

Controlled/living radical polymerization was developed to synthesize branched polyacrylates and polystyrene with tunable degrees of branching and low dispersities. This method is based on a polymerization-induced branching process that occurs when n-butyl α-bromoacrylate is copolymerized under atom transfer radical polymerization conditions. This novel branching polymerization demonstrates excellent synthetic versatility, enabling the preparation of complex macromolecular architectures constructed from branched-polymer building blocks.


Asunto(s)
Resinas Acrílicas/síntesis química , Poliestirenos/síntesis química , Acrilatos/química , Estructura Molecular , Polimerizacion
17.
Anal Chem ; 91(21): 13831-13837, 2019 11 05.
Artículo en Inglés | MEDLINE | ID: mdl-31560517

RESUMEN

Exploring the fabrication of an electrode with high photoelectric conversion efficiency and abundant functional groups for ideal photoelectrochemical (PEC) sensor development is highly urgent but faces a significant challenge. Herein we report an electropolymerization strategy for the preparation of phenothiazine polymeric film on an indium tin oxide (ITO) surface (PPT/ITO), within only a few seconds, and monomers. The fabricated PPT/ITO electrode possessed excellent stability and abundant quaternary ammonium salt groups for developing a highly sensitive PEC sensor through electrostatic binding with negatively charged materials. In this context, a CdS QDs-functionalized PPT/ITO electrode (CdS/PPT/ITO) was proposed and applied to the analysis of chlorpyrifos, used as a model target organophosphorous pesticide (OP). The thiocholine generated from acetylcholinesterase (AChE)-induced catalyzed hydrolysis of acetylthiocholine (ATCh) efficiently directed CdS QDs away from PPT/ITO via electrostatic repulsion, subsequently decreasing PEC current, whereas chlorpyrifos prohibited the generation of thiocholine through inhibiting AChE activity. As compared to the case where chlorpyrifos is absent, significantly enhanced PEC current is determined and is proportional to chlorpyrifos amounts. Thus, the developed CdS/PPT/ITO-based PEC sensor achieved excellent chlorpyrifos biosensing with improved sensitivity down to approximately ng/mL level with good specificity. We envision the proposed strategy will provide a new path to conveniently fabricate photoelectrodes possessing high performance, which will have more useful applications in PEC sensing.


Asunto(s)
Técnicas Biosensibles/métodos , Técnicas Electroquímicas/métodos , Fenotiazinas/química , Polímeros/química , Acetilcolinesterasa/metabolismo , Acetilcolinesterasa/farmacología , Compuestos de Cadmio , Cloropirifos/análisis , Inhibidores de la Colinesterasa/análisis , Electrodos , Polimerizacion , Puntos Cuánticos/química , Electricidad Estática , Sulfuros , Compuestos de Estaño/química
18.
Bioinformatics ; 34(1): 1-8, 2018 01 01.
Artículo en Inglés | MEDLINE | ID: mdl-28961734

RESUMEN

Motivation: Analysis of RNA sequencing (RNA-Seq) data in human saliva is challenging. Lack of standardization and unification of the bioinformatic procedures undermines saliva's diagnostic potential. Thus, it motivated us to perform this study. Results: We applied principal pipelines for bioinformatic analysis of small RNA-Seq data of saliva of 98 healthy Korean volunteers including either direct or indirect mapping of the reads to the human genome using Bowtie1. Analysis of alignments to exogenous genomes by another pipeline revealed that almost all of the reads map to bacterial genomes. Thus, salivary exRNA has fundamental properties that warrant the design of unique additional steps while performing the bioinformatic analysis. Our pipelines can serve as potential guidelines for processing of RNA-Seq data of human saliva. Availability and implementation: Processing and analysis results of the experimental data generated by the exceRpt (v4.6.3) small RNA-seq pipeline (github.gersteinlab.org/exceRpt) are available from exRNA atlas (exrna-atlas.org). Alignment to exogenous genomes and their quantification results were used in this paper for the analyses of small RNAs of exogenous origin. Contact: dtww@ucla.edu.


Asunto(s)
Biología Computacional/métodos , Análisis de Secuencia de ARN/métodos , Programas Informáticos , Secuenciación de Nucleótidos de Alto Rendimiento/métodos , Humanos , ARN , Saliva/química
19.
J Viral Hepat ; 26 Suppl 1: 77-84, 2019 07.
Artículo en Inglés | MEDLINE | ID: mdl-31380586

RESUMEN

Chronic hepatitis B virus (HBV) infection (CHB) in children remains a public health challenge despite significant success in programme is established to prevent mother-to-child transmission. In particular, CHB in Chinese children are mostly acquired through vertical transmission, which differs from the common infection route reported in other countries and regions. This situation has resulted in a high endemic prevalence of CHB in Chinese adults. Thus, successful treatment of children with CHB will prevent the development of advanced liver diseases in late adulthood. However, there is still no consensus on the clinical guideline to treat paediatric CHB. In this study, we evaluated the potential of interferon alpha (IFNa) treatment for Chinese children with CHB. A total of 41 patients with CHB aged 3-17 years were enrolled in this retrospective study: 21 patients were treated with pegylated (PEG)-IFNa and 20 patients without treatment served as the control group. The rates of HBV DNA suppression, hepatitis B e antigen (HBeAg) clearance and hepatitis B surface antigen (HBsAg) clearance were significantly higher in the PEG-IFNa treatment group than in the control group (P < 0.05 at 48 weeks). Unexpectedly, PEG-IFNa treatment achieved a high rate of HBsAb production, far exceeding the clinical outcome in documented PEG-IFNa-treated CHB adults. Further analysis revealed that younger children (3-6 years old) were more responsive to PEG-IFNa treatment with respect to achieving a protective level of HBsAb in a short treatment cycle than adolescents (10-17 years old). Overall, these results indicate that the immune system of children might have a preserved PEG-IFNa-mediated mechanism to completely control HBV, which can help to design new strategies to treat CHB patients.


Asunto(s)
Antivirales/uso terapéutico , Antígenos de Superficie de la Hepatitis B/sangre , Hepatitis B Crónica/sangre , Hepatitis B Crónica/tratamiento farmacológico , Interferón-alfa/uso terapéutico , Adolescente , Antivirales/administración & dosificación , Antivirales/efectos adversos , Niño , Preescolar , ADN Viral , Femenino , Hepatitis B Crónica/diagnóstico , Humanos , Interferón-alfa/administración & dosificación , Interferón-alfa/efectos adversos , Masculino , Polietilenglicoles/administración & dosificación , Polietilenglicoles/efectos adversos , Polietilenglicoles/uso terapéutico , Proteínas Recombinantes/administración & dosificación , Proteínas Recombinantes/efectos adversos , Proteínas Recombinantes/uso terapéutico , Seroconversión , Carga Viral
20.
J Bone Miner Metab ; 37(5): 773-779, 2019 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-30607618

RESUMEN

Mutations in Serpinf1 gene which encodes pigment epithelium-derived factor (PEDF) lead to osteogenesis imperfecta type VI whose hallmark is defective matrix mineralization. We reported previously that PEDF reduced expression and synthesis of Sost/Sclerostin as well as other osteocytes genes encoding proteins that regulate matrix mineralization [1]. To determine whether PEDF had an effect on osteocyte gene expression in bone, we used bone explant cultures. First, osteocytes were isolated from surgical waste of bone fragments obtained from patients undergoing elective foot surgeries under approved IRB protocol by Penn State College of Medicine IRB committee. Primary osteocytes treated with PEDF reduced expression and synthesis of Sost/Sclerostin and matrix phosphoglycoprotein (MEPE) as well as dentin matrix protein (DMP-1). On the whole, PEDF reduced osteocyte protein synthesis by 50% and by 75% on mRNA levels. For bone explants, following collagenase digestion, bone fragments were incubated in alpha-MEM supplemented with 250 ng/ml of PEDF or BSA. After 7 days of incubation in a medium supplemented with PEDF, analysis of mRNA by PCR and protein by western blotting of encoded osteocyte proteins showed reduced Sclerostin synthesis by 39% and MEPE by 27% when compared to fragments incubated in medium supplemented with BSA. mRNA expression levels of osteocytes in bone fragments treated with PEDF were reduced by 50% for both SOST and MEPE when compared to BSA-treated bone fragments. Taken together, the data indicate that PEDF has an effect on osteocyte gene expression in bone and encourage further studies to examine effect of PEDF on bone formation indices in animal models and its effect on osteocyte gene expression in vivo following PEDF administration.


Asunto(s)
Proteínas Morfogenéticas Óseas/metabolismo , Huesos/metabolismo , Proteínas del Ojo/farmacología , Regulación de la Expresión Génica/efectos de los fármacos , Factores de Crecimiento Nervioso/farmacología , Osteocitos/metabolismo , Serpinas/farmacología , Técnicas de Cultivo de Tejidos , Proteínas Adaptadoras Transductoras de Señales , Animales , Proteínas Morfogenéticas Óseas/genética , Células Cultivadas , Proteínas de la Matriz Extracelular/genética , Proteínas de la Matriz Extracelular/metabolismo , Marcadores Genéticos/genética , Glicoproteínas/genética , Glicoproteínas/metabolismo , Humanos , Persona de Mediana Edad , Osteocitos/efectos de los fármacos , Fosfoproteínas/genética , Fosfoproteínas/metabolismo
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