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1.
Cancer Sci ; 2024 May 30.
Artículo en Inglés | MEDLINE | ID: mdl-38816349

RESUMEN

Glioma is the most common malignant tumor in the central nervous system, and it is crucial to uncover the factors that influence prognosis. In this study, we utilized Mfuzz to identify a gene set that showed a negative correlation with overall survival in patients with glioma. Gene Ontology (GO) enrichment analyses were then undertaken to gain insights into the functional characteristics and pathways associated with these genes. The expression distribution of Hyaluronan Synthase 2 (HAS2) was explored across multiple datasets, revealing its expression patterns. In vitro and in vivo experiments were carried out through gene knockdown and overexpression to validate the functionality of HAS2. Potential upstream transcription factors of HAS2 were predicted using transcriptional regulatory databases, and these predictions were experimentally validated using ChIP-PCR and dual-luciferase reporter gene assays. The results showed that elevated expression of HAS2 in glioma indicates poor prognosis. HAS2 was found to play a role in activating an antiferroptosis pathway in glioma cells. Inhibiting HAS2 significantly increased cellular sensitivity to ferroptosis-inducing agents. Finally, we determined that the oncogenic effect of HAS2 is mediated by the key receptor of the WNT pathway, FZD7.

2.
BMC Microbiol ; 24(1): 109, 2024 Apr 02.
Artículo en Inglés | MEDLINE | ID: mdl-38565985

RESUMEN

BACKGROUND: The current understanding of acquired chromosomal colistin resistance mechanisms in Enterobacterales primarily involves the disruption of the upstream PmrAB and PhoPQ two-component system (TCS) control caused by mutations in the regulatory genes. Interestingly, previous studies have yielded conflicting results regarding the interaction of regulatory genes related to colistin resistance in Escherichia coli, specifically those surrounding PhoPQ and PmrAB TCS. RESULTS: In our study, we focused on two clinical non-mcr colistin-resistant strains of E. coli, TSAREC02 and TSAREC03, to gain a better understanding of their resistance mechanisms. Upon analysis, we discovered that TSAREC02 had a deletion (Δ27-45) in MgrB, as well as substitutions (G206R, Y222H) in PmrB. On the other hand, TSAREC03 exhibited a long deletion (Δ84-224) in PhoP, along with substitutions (M1I, L14P, P178S, T235N) in PmrB. We employed recombinant DNA techniques to explore the interaction between the PhoPQ and PmrAB two-component systems (TCSs) and examine the impact of the mutated phoPQ and pmrB genes on the minimum inhibitory concentrations (MICs) of colistin. We observed significant changes in the expression of the pmrD gene, which encodes a connector protein regulated by the PhoPQ TCS, in the TSAREC02 wild-type (WT)-mgrB replacement mutant and the TSAREC03 WT-phoP replacement mutant, compared to their respective parental strains. However, the expressions of pmrB/pmrA, which reflect PmrAB TCS activity, and the colistin MICs remained unchanged. In contrast, the colistin MICs and pmrB/pmrA expression levels were significantly reduced in the pmrB deletion mutants from both TSAREC02 and TSAREC03, compared to their parental strains. Moreover, we were able to restore colistin resistance and the expressions of pmrB/pmrA by transforming a plasmid containing the parental mutated pmrB back into the TSAREC02 and TSAREC03 mutants, respectively. CONCLUSION: While additional data from clinical E. coli isolates are necessary to validate whether our findings could be broadly applied to the E. coli population, our study illuminates distinct regulatory pathway interactions involving colistin resistance in E. coli compared to other species of Enterobacterales. The added information provided by our study contribute to a deeper understanding of the complex pathway interactions within Enterobacterales.


Asunto(s)
Antibacterianos , Colistina , Colistina/farmacología , Antibacterianos/farmacología , Escherichia coli/metabolismo , Proteínas Bacterianas/genética , Proteínas Bacterianas/metabolismo , Farmacorresistencia Bacteriana/genética , Pruebas de Sensibilidad Microbiana
3.
Molecules ; 29(4)2024 Feb 14.
Artículo en Inglés | MEDLINE | ID: mdl-38398604

RESUMEN

Andrographis paniculata is a medicinal plant traditionally used to produce diterpene lactones and flavonoids, which possess various biological activities. Widely distributed in China, India, and other Southeast Asia countries, A. paniculata has become an important economic crop, significantly treating SARS-CoV-2, and is being cultivated on a large scale in southern China. The biosynthesis of active ingredients in A. paniculata are regulated and controlled by genes, but their specific roles are still not fully understood. To further explore the growth regulation factors and utilization of its medicinal parts of this industrial crop, chemical and transcriptome analyses were conducted on the roots, stems, and leaves of A. paniculata to identify the biosynthesis pathways and related candidate genes of the active ingredients. The chemical analysis revealed that the main components of A. paniculata were diterpene lactones and flavonoids, which displayed potential ability to treat SARS-CoV-2 through molecular docking. Moreover, the transcriptome sequencing annotated a total of 40,850 unigenes, including 7962 differentially expressed genes. Among these, 120 genes were involved in diterpene lactone biosynthesis and 60 genes were involved in flavonoid biosynthesis. The expression of diterpene lactone-related genes was the highest in leaves and the lowest in roots, consistent with our content determination results. It is speculated that these highly expressed genes in leaves may be involved in the biosynthesis pathway of diterpenes. Furthermore, two class Ⅰ terpene synthases in A. paniculata transcriptome were also annotated, providing reference for the downstream pathway of the diterpene lactone biosynthesis. With their excellent market value, our experiments will promote the study of the biosynthetic genes for active ingredients in A. paniculata and provide insights for subsequent in vitro biosynthesis.


Asunto(s)
Andrographis , Diterpenos , Terpenos/metabolismo , Transcriptoma , Andrographis/genética , Andrographis/química , Flavonoides/metabolismo , Simulación del Acoplamiento Molecular , Diterpenos/química , Lactonas/metabolismo , Antivirales/metabolismo
4.
J Occup Environ Hyg ; 21(4): 270-286, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38451632

RESUMEN

Three-dimensional (3D) printing is an emerging and booming industry in Taiwan. Compared to traditional manufacturing, 3D printing has various advantages, such as advanced customization, additive manufacturing, reduced mold opening time, and reduced consumption of precursors. In this study, the real-time monitoring of particulate matter (PM) and total volatile organic compound (TVOC) emissions from various filaments is investigated using fused deposition modeling with material extrusion technology, a liquid-crystal display, a stereolithography apparatus based on vat photopolymerization technology, and binder jetting for occupational settings. An exposure assessment for nearby workers using the 3D printing process was performed, and improvement measures were recommended. Nine 3D printing fields were measured. The generation rate of ultrafine particles ranged from 1.19 × 1010 to 4.90 × 1012 #/min, and the geometric mean particle size ranged from 30.91 to 55.50 nm. The average concentration of ultrafine particles ranged from 2.31 × 103 to 7.36 × 104 #/cm3, and the PM2.5 and PM10 concentrations in each field ranged from 0.74 ± 0.27 to 12.46 ± 5.61 µg/m3 and from 2.39 ± 0.60 to 30.65 ± 21.26 µg/m3, respectively. The TVOC concentration ranged from 0.127 ± 0.012 to 1.567 ± 0.172 ppm. The respiratory deposition (RDUFPs) dose ranged from 2.02 × 1013 to 5.54 × 1014 nm2/day. Depending on the operating conditions, appropriate control and protective measures should be employed to protect workers' health.


Asunto(s)
Contaminación del Aire Interior , Compuestos Orgánicos Volátiles , Humanos , Taiwán , Contaminación del Aire Interior/análisis , Material Particulado/análisis , Impresión Tridimensional , Compuestos Orgánicos Volátiles/análisis , Lugar de Trabajo
5.
Antimicrob Agents Chemother ; 67(11): e0066523, 2023 11 15.
Artículo en Inglés | MEDLINE | ID: mdl-37843305

RESUMEN

Acinetobacter baumannii-calcoaceticus complex (ABC) causes severe infections that are difficult to treat due to pre-existing antibiotic resistance. Sulbactam-durlobactam (SUL-DUR) is a targeted ß-lactam/ß-lactamase inhibitor combination antibiotic designed to treat serious infections caused by Acinetobacter, including multidrug- and carbapenem-resistant strains. In a recent global surveillance study of 5,032 ABC clinical isolates collected from 2016 to 2021, less than 2% of ABC isolates had SUL-DUR MIC values >4 µg/mL. Molecular characterization of these isolates confirmed the primary drivers of resistance are metallo-ß-lactamases or penicillin-binding protein 3 (PBP3) mutations, as previously described. In addition, this study shows that certain common PBP3 variants, such as A515V, are insufficient to confer sulbactam resistance and that the efflux of durlobactam by AdeIJK is likely to play a role in a subset of strains.


Asunto(s)
Acinetobacter baumannii , Sulbactam , Sulbactam/farmacología , Sulbactam/uso terapéutico , Antibacterianos/uso terapéutico , Compuestos de Azabiciclo/farmacología , Inhibidores de beta-Lactamasas/farmacología , Inhibidores de beta-Lactamasas/uso terapéutico , Monobactamas , Pruebas de Sensibilidad Microbiana
6.
J Transl Med ; 21(1): 863, 2023 11 28.
Artículo en Inglés | MEDLINE | ID: mdl-38017538

RESUMEN

BACKGROUND: Glioblastoma, the most common primary malignant tumor of the brain, is associated with poor prognosis. Glioblastoma cells exhibit high proliferative and invasive properties, and glioblastoma stem cells (GSCs) have been shown to play a crucial role in the malignant behavior of glioblastoma cells. This study aims to investigate the molecular mechanisms involved in GSCs maintenance and malignant progression. METHODS: Bioinformatics analysis was performed based on data from public databases to explore the expression profile of Mitotic arrest deficient 2 like 2 (MAD2L2) and its potential function in glioma. The impact of MAD2L2 on glioblastoma cell behaviors was assessed through cell viability assays (CCK8), colony formation assays, 5-Ethynyl-2'-deoxyuridine (EDU) incorporation assays, scratch assays, and transwell migration/invasion assays. The findings from in vitro experiments were further validated in vivo using xenograft tumor model. GSCs were isolated from the U87 and LN229 cell lines through flow cytometry and the stemness characteristics were verified by immunofluorescence staining. The sphere-forming ability of GSCs was examined using the stem cell sphere formation assay. Bioinformatics methods were conducted to identified the potential downstream target genes of MAD2L2, followed by in vitro experimental validation. Furthermore, potential upstream transcription factors that regulate MAD2L2 expression were confirmed through chromatin immunoprecipitation (ChIP) and dual-luciferase reporter assays. RESULTS: The MAD2L2 exhibited high expression in glioblastoma samples and showed significant correlation with patient prognosis. In vitro and in vivo experiments confirmed that silencing of MAD2L2 led to decreased proliferation, invasion, and migration capabilities of glioblastoma cells, while decreasing stemness characteristics of glioblastoma stem cells. Conversely, overexpression of MAD2L2 enhanced these malignant behaviors. Further investigation revealed that MYC proto-oncogene (c-MYC) mediated the functional role of MAD2L2 in glioblastoma, which was further validated through a rescue experiment. Moreover, using dual-luciferase reporter gene assays and ChIP assays determined that the upstream transcription factor E2F-1 regulated the expression of MAD2L2. CONCLUSION: Our study elucidated the role of MAD2L2 in maintaining glioblastoma stemness and promoting malignant behaviors through the regulation of c-MYC, suggesting its potential as a therapeutic target.


Asunto(s)
Neoplasias Encefálicas , Glioblastoma , Glioma , Animales , Humanos , Glioblastoma/patología , Neoplasias Encefálicas/patología , Proliferación Celular , Células Madre Neoplásicas/patología , Glioma/patología , Modelos Animales de Enfermedad , Luciferasas/metabolismo , Línea Celular Tumoral , Regulación Neoplásica de la Expresión Génica , Proteínas Mad2/genética , Proteínas Mad2/metabolismo
7.
Environ Res ; 234: 116553, 2023 10 01.
Artículo en Inglés | MEDLINE | ID: mdl-37406722

RESUMEN

The ubiquitous and refractory benzophenone (BP)-type ultraviolet filters, which are also endocrine disruptors, were commonly detected in the aquatic matrix and could not be efficiently removed by conventional wastewater treatment processes, thus causing extensive concern. Herein, a novel ternary nanocomposite, P-g-CN/α-Bi2O3/WO3 (P-gBW), was successfully fabricated by mixing cocalcinated components and applied to the decomposition of BP-type ultraviolet filters. The dual-Z-scheme heterostructure of P-gBW enhances visible-light absorption, efficiently facilitates separation and mobility, and prolongs the lifetime of photoinduced charge carriers via double charge transfer mechanisms. The optimum 95 wt% P-gBW exhibited excellent photocatalytic activity, degrading 96% 4-hydroxy benzophenone (4HBP) within 150 min and 93% 2,2',4,4'-tetrahydroxybenzophenone (BP-2) within 100 min under visible-light illumination, respectively. The pseudo-first-order rate constant of 4HBP (1.15 h-1) was 6.8-, 3.1-, 3.3- and 2.2-fold higher than those of WO3, P-g-CN, α-Bi2O3, and P-g-CN/α-Bi2O3, respectively, while that of BP-2 (1.71 h-1) was 5.2-, 2.2-, 3.2- and 1.5-fold higher, respectively. The improved photocatalytic degradation was attributed to efficient photoinduced charge carrier separation and migration and prevented the recombination of electron holes, as verified by photoluminescence, transient photocurrent response, and electrochemical impedance spectroscopy. Trapping experiments, electron paramagnetic resonance, and band energy position indicated an efficient dual-Z-scheme heterostructure.


Asunto(s)
Benzofenonas , Luz , Iluminación , Espectroscopía de Resonancia por Spin del Electrón
8.
Anal Bioanal Chem ; 414(14): 4067-4077, 2022 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-35524003

RESUMEN

Liver disease has emerged as a healthcare burden because of high hospitalization rates attributed both to steatohepatitis and to severe hepatic toxicity associated with changes of drug exposure. Early detection of hepatic insufficiency is critical to preventing long-term liver damage. The galactose single-point test is recommended by the US FDA as a sensitive means to quantify liver function, yet the conventional method used for quantitation of circulating galactose still relies on the standard colorimetric method, requiring time-consuming and labor-intensive processes, and is confined to the medical laboratory, thus limiting prevalence. To facilitate time- and cost-effective disease management particularly during a pandemic, a pocket-sized rapid quantitative device consisting of a biosensor and electrochemical detection has been developed. An in vitro validation study demonstrated that the coefficient of variation was less than 15% and deviations were between -4 and 14% in the range of 100-1500 µg/mL. The device presented good linear fit (correlation coefficient, r = 0.9750) over the range of 150-1150 µg/mL. Moreover, the device was found to be free from interference of common endogenous and exogenous substances, and deviated hematocrit, enabling a direct measurement of galactose in the whole blood without sample pre-treatment steps. The clinical validation comprising 118 subjects showed high concordance (r = 0.953) between the device and the conventional colorimetric assay. Thus, this novel miniaturized device is reliable and robust for routine assessment of quantitative liver function intended for follow-up of hepatectomy, drug dose adjustment, and screening for galactosemia, allowing timely and cost-effective clinical management of patients.


Asunto(s)
Técnicas Biosensibles , Galactosemias , Galactosa , Galactosemias/diagnóstico , Humanos , Hígado , Sistemas de Atención de Punto
9.
Chem Biodivers ; 19(6): e202200334, 2022 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-35561089

RESUMEN

Three new alkaloids (1-3), one new diphenyl ether (4) and fifteen known alkaloids (5-19) were isolated from the rattan stems of Sinomenium acutum. Comprehensive analyses of HR-ESI-MS, 1D (1 H and 13 C), 2D-NMR (1 H-1 H COSY, HSQC, HMBC, NOESY), circular dichroism (CD), UV and IR revealed the structures and absolute configurations of these new compounds. The structures of other compounds were determined by comparison of their 1 H and 13 C-NMR data with previous literature reports. By measuring the amount of NO produced, the anti-inflammatory properties of the isolated compounds were studied. The results showed that compounds 4 and 5 had strong NO inhibitory activity.


Asunto(s)
Alcaloides , Artritis Reumatoide , Medicamentos Herbarios Chinos , Alcaloides/química , Alcaloides/farmacología , Artritis Reumatoide/tratamiento farmacológico , China , Medicamentos Herbarios Chinos/química , Medicamentos Herbarios Chinos/farmacología , Medicina Tradicional , Estructura Molecular , Sinomenium/química
10.
Chem Biodivers ; 19(7): e202200137, 2022 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-35726787

RESUMEN

Regulation of key digestive enzymes is currently considered an effective remedy for diabetes mellitus. In this study, bioactive constituents were purified from Terminalia boivinii fruits and identified by 1 H-NMR, 13 C-NMR and EI-MS. In vitro and in silico methods were used to evaluate α-glucosidase, α-amylase, and lipase inhibition activities. Compounds 1, 2, and 4-7 with IC50 values between 89 and 445 µM showed stronger α-glucosidase inhibitory activities than the antihyperglycemic drug acarbose (IC50 =1463.0±29.5 µM). However, the compounds showed lower inhibitory effects against α-amylase and lipase with IC50 values above 500 µM than acarbose (IC50 =16.7±3.5 µM) and ursolic acid (IC50 =89.5±5.6 µM), respectively. Lineweaver-Burk plots showed that compounds 1, 2, and 7 were non-competitive inhibitors, compounds 4 and 5 were competitive inhibitors and compound 6 was a mixed-type inhibitor. Fluorescence spectroscopic data showed that the compounds altered the microenvironment and conformation of α-glucosidase. Computer simulations indicated that the compounds and enzyme interacted primarily through hydrogen bonding. The findings indicated that the compounds were inhibitors of α-glucosidase and provided significant structural basis for understanding the binding activity of the compounds with α-glucosidase.


Asunto(s)
Terminalia , alfa-Glucosidasas , Acarbosa , Frutas/metabolismo , Inhibidores de Glicósido Hidrolasas/química , Inhibidores de Glicósido Hidrolasas/farmacología , Cinética , Lipasa/metabolismo , Simulación del Acoplamiento Molecular , alfa-Amilasas/metabolismo , alfa-Glucosidasas/metabolismo
11.
Int J Mol Sci ; 23(21)2022 Oct 31.
Artículo en Inglés | MEDLINE | ID: mdl-36362072

RESUMEN

A kind of hydroxylated polymethoxyflavone (PMFs) existing in the citrus genus, 5-Demethyltangeretin (5-DTAN), has been reported to possess several bioactivities in vitro and in vivo. The aim of this study was to investigate whether acetylation could enhance the anticancer activity and oral bioavailability of 5-DTAN. PC-3 human prostate cancer cells were treated with tangeretin (TAN), 5-DTAN, and 5-acetylated TAN (5-ATAN), and the results showed that the cytotoxic effect 5-ATAN (IC50 value of 5.1 µM) on the cell viability of PC-3 cells was stronger than that of TAN (IC50 value of 17.2 µM) and 5-DTAN (IC50 value of 11.8 µM). Compared to 5-DTAN, 5-ATAN treatment caused a more pronounced DNA ladder, increased the sub-G1 phase population, and induced G2/M phase arrest in the cell cycle of PC-3 cells. We also found that 5-ATAN triggered the activation of caspase-3 and the progression of the intrinsic mitochondrial pathway in PC-3 cells, suggesting the induction of apoptosis. In a cell wound healing test, 5-ATAN dose-dependently reduced the cell migration, and the expression of matrix metalloproteinase-2 (MMP-2) and matrix metalloproteinase-9 (MMP-9) was decreased after 48 h of 5-ATAN treatment. Moreover, oral administration of 5-ATAN showed a significantly stronger inhibitory effect on tumor size and tumor weight in tumor-bearing nude mice than those of vehicle or the 5-DTAN group (p < 0.05). Furthermore, pharmacokinetic results showed that single-dose oral administration of 5-ATAN exhibited a higher maximum concentration (Cmax) and area under the curve (AUC) of 5-DTAN in plasma than that of 5-DTAN. More extensive distribution of 5-DTAN to most tissues of mice was also observed in mice treated with 5-ATAN for 7 days. In conclusion, acetylation strongly enhances the anticancer activity and oral bioavailability of 5-DTAN and could be a promising strategy to promote the potential bioactivities of natural products.


Asunto(s)
Antineoplásicos , Flavonas , Animales , Humanos , Masculino , Ratones , Acetilación , Apoptosis , Disponibilidad Biológica , Línea Celular Tumoral , Metaloproteinasa 2 de la Matriz , Ratones Desnudos , Flavonas/química , Flavonas/farmacocinética , Antineoplásicos/química , Antineoplásicos/farmacocinética
12.
Aerobiologia (Bologna) ; 37(2): 243-252, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33462522

RESUMEN

The liquid impingers can be used for sampling of viral aerosols, such as COVID-19 virus, influenza, and measles. However, the lowest cutoff diameter of commercially available liquid impingers was about 0.3 µm, and the physical collection efficiency for nano-bioaerosol is only about 10-20%. Here, we enhanced the impinger's collection efficiency and recovery of viable viral aerosols by using packed glass beads and selected sampling media (1% peptone and lysogeny broth, LB). Single-stranded RNA (ssRNA) MS2 bacteriophage with uranine (as a physical tracer) was used as model viral aerosols. The effects of different sampling flow rates (4, 6, and 12.5 L per minute) and different sampling time (10, 20, and 30 min) on the collection efficiency and recovery of MS2 aerosols were also tested. Collection efficiency and recovery of viable viral aerosols were analyzed as a function of sampling media, flow rate, and sampling time and packed glass beads by using a general linear model. Although the packed glass beads considerably enhanced the collection efficiency of the liquid impinger for MS2 aerosols, the recovery of viable MS2 becomes lower due to the higher pressure drop across the impinger. Using peptone or LB as sampling media, reducing sampling flow rate, and decreasing sampling time was proven to improve the recovery of viable MS2. Conclusively, this study provides some practical methods to improve the collection efficiency of liquid impinger for viral aerosols and preserve their viability.

13.
Artículo en Inglés | MEDLINE | ID: mdl-32284375

RESUMEN

We report the first clinical Escherichia coli strain EC3000 with concomitant chromosomal colistin and carbapenem resistance. A novel in-frame deletion, Δ6-11 (RPISLR), in pmrB that contributes to colistin resistance was verified using recombinant DNA techniques. Although being less fit than the wild-type (WT) strain or EC3000 revertant (chromosomal replacement of WT pmrB in EC3000), a portion of serially passaged EC3000 strains preserving colistin resistance without selective pressure raises the concern for further spread.


Asunto(s)
Colistina , Farmacorresistencia Bacteriana , Antibacterianos/farmacología , Proteínas Bacterianas/genética , Carbapenémicos/farmacología , Colistina/farmacología , Farmacorresistencia Bacteriana/genética , Escherichia coli/genética , Pruebas de Sensibilidad Microbiana , Eliminación de Secuencia/genética
14.
Biotechnol Bioeng ; 117(4): 933-944, 2020 04.
Artículo en Inglés | MEDLINE | ID: mdl-31889302

RESUMEN

Rice straw, a common agricultural waste, is used as a potential feedstock for bioethanol production. Currently, bioethanol is made mostly from the microbial fermentation of starch-containing raw materials. Therefore, genetically engineered starch-excess rice straw through interference of starch degradation as a potential strategy to enhance bioethanol production was evaluated in this study. Arabidopsis Starch Excess 4 (SEX4) encodes a chloroplast-localized glucan phosphatase and plays a role in transitory starch degradation. Despite the identification of a SEX4 homolog in rice, OsSEX4, its biological function remains uncertain. Ectopic expression of OsSEX4 complementary DNA complemented the leaf starch-excess phenotype of the Arabidopsis sex4-4 mutant. OsSEX4-knockdown transgenic rice plants were generated using the RNA interference approach. Starch accumulation was higher in OsSEX4-knockdown suspension-cultured cells, leaves, and rice straw compared with the wild type, suggesting that OsSEX4 plays an important role in degradation of transitory starch. The OsSEX4-knockdown rice plants showed normal plant growth and no yield penalty. Starch-excess OsSEX4-knockdown rice straw used as feedstock for fermentation resulted in improved bioethanol yield, with a 50% increase in ethanol production in a vertical mass-flow type bioreactor, compared with that of the wild-type straw.


Asunto(s)
Fosfatasas de Especificidad Dual , Etanol/metabolismo , Oryza , Proteínas de Plantas , Almidón , Biocombustibles , Reactores Biológicos , Fosfatasas de Especificidad Dual/genética , Fosfatasas de Especificidad Dual/metabolismo , Técnicas de Silenciamiento del Gen , Ingeniería Genética/métodos , Oryza/genética , Oryza/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Plantas Modificadas Genéticamente/genética , Plantas Modificadas Genéticamente/metabolismo , Almidón/genética , Almidón/metabolismo
15.
Indoor Air ; 29(3): 439-449, 2019 05.
Artículo en Inglés | MEDLINE | ID: mdl-30738001

RESUMEN

A novel antimicrobial composite of zero-valent silver nanoparticles (AgNPs), titania (TiO2 ), and chitosan (CS) was prepared via photochemical deposition of AgNPs on a CS-TiO2 matrix (AgNPs@CS-TiO2 ). Electron microscopy showed that the AgNPs were well dispersed on the CS-TiO2 , with diameters of 6.69-8.84 nm. X-ray photoelectron spectra indicated that most of the AgNPs were reduced to metallic Ag. Fourier-transform infrared spectroscopy indicated that some AgNPs formed a chelate with CS through coordination of Ag+ with the CS amide II groups. The zones of inhibition of AgNPs@CS-TiO2 for bacteria (Escherichia coli and Staphylococcus epidermidis) and fungi (Aspergillus niger and Penicillium spinulosum) were 6.72-11.08 and 5.45-5.77 mm, respectively, and the minimum (critical) concentrations of AgNPs required to inhibit the growth of bacteria and fungi were 7.57 and 16.51 µg-Ag/mm2 , respectively. The removal efficiency of a AgNPs@TiO2 -CS bed filter for bioaerosols (η) increased with the packing depth, and the optimal filter quality (qF) occurred for packing depths of 2-4 cm (qF = 0.0285-0.103 Pa-1 ; η = 57.6%-98.2%). When AgNPs@TiO2 -CS bed filters were installed in the ventilation systems of hospital wards, up to 88% of bacteria and 97% of fungi were removed within 30 minutes. Consequently, AgNPs@TiO2 -CS has promising potentials in bioaerosol purification.


Asunto(s)
Antiinfecciosos/administración & dosificación , Quitosano , Desinfección/métodos , Nanopartículas del Metal , Nanocompuestos/administración & dosificación , Plata , Titanio , Aerosoles , Filtros de Aire , Microbiología del Aire , Antiinfecciosos/química , Unidades Hospitalarias , Nanocompuestos/química , Espectroscopía Infrarroja por Transformada de Fourier , Ventilación/métodos
16.
Artículo en Inglés | MEDLINE | ID: mdl-31177909

RESUMEN

Preschool children have a higher respiratory rate per unit body weight than adults, and their respiratory systems are not mature. Hence, children may have more health risks associated with particulate matter (PM) exposure. In this study, we assessed the exposure of preschool children and their caregivers to PM and the resulting health risks. The PM concentrations at heights of 60-80 cm (preschool children) and 150 cm (adults) were measured at ten indoor and eight outdoor sites in the Taipei metropolitan area from March 2015 to February 2017. Four PM2.5 and seven PM10 indoor measurements exceeded the indoor air quality standard of Taiwan, whereas only two PM2.5 outdoor measurements exceeded the ambient air quality standard. The outdoor PM concentrations were related to traffic emissions, whereas the indoor PM concentrations were associated with ventilation rate and occupant density. The chronic daily PM1, PM2.5, and PM10 intakes of preschool children were notably higher than those of adults. In addition, the hazard quotient resulting from PM2.5 exposure indicated a significant health risk for preschool children (93.74% greater than 1). Consequently, reducing the exposure of preschool children to PM2.5 is an emerging issue in the Taipei metropolitan area.


Asunto(s)
Exposición a Riesgos Ambientales/análisis , Enfermedades Ambientales/epidemiología , Material Particulado/análisis , Adulto , Contaminantes Atmosféricos/análisis , Contaminación del Aire/análisis , Contaminación del Aire Interior/análisis , Cuidadores/estadística & datos numéricos , Cuidado del Niño/estadística & datos numéricos , Preescolar , Exposición a Riesgos Ambientales/estadística & datos numéricos , Enfermedades Ambientales/etiología , Monitoreo del Ambiente/métodos , Humanos , Exposición por Inhalación/análisis , Exposición por Inhalación/estadística & datos numéricos , Parques Recreativos/estadística & datos numéricos , Tamaño de la Partícula , Enfermedades Respiratorias/epidemiología , Enfermedades Respiratorias/etiología , Factores de Riesgo , Taiwán/epidemiología
17.
Toxicol Appl Pharmacol ; 342: 39-49, 2018 03 01.
Artículo en Inglés | MEDLINE | ID: mdl-29407773

RESUMEN

The mono-PEGylated recombinant human interleukin-11 (rhIL-11) was evaluated for its pharmacology and toxicology profile in non-human primates. This PEGylated IL-11 (PEG-IL11) showed a much prolonged circulating half-life of 67h in cynomolgus monkeys as compared to its un-PEGylated counterpart (~3h) through subcutaneous administration, implicating that a single injection of the recommended dose will effectively enhance thrombopoiesis in humans for a much longer period of time compared to rhIL-11 in humans (t1/2=6.9h). The toxicokinetics study of single dose and multiple doses showed that systemic exposure was positively correlated with the dosing level, implying that efficacy and toxicity were mechanism-based. A single high dose at 6.25mg/kg through subcutaneous route revealed tolerable and transient toxicity. Multiple-dose in monkeys receiving 0.3mg/kg weekly of the drug developed only mild to moderate toxicity. Major adverse events and immunogenicity in monkeys were only observed in the overdose groups. Bones were positively impacted; while reversible toxicities in heart, liver, kidney and lung observed were likely to be consequences of fluid retention. In summary, the PEG moiety on rhIL-11 did not elicit additional toxicities, and the drug under investigation was found to be well tolerated in monkeys after receiving a single effective dose of 0.1-0.3mg/kg through subcutaneous delivery, which may be allometrically scaled to a future clinical dose at 30-100µg/kg, creating a potential long acting, safer, and more convenient treatment approach based on rhIL-11.


Asunto(s)
Interleucina-11/administración & dosificación , Polietilenglicoles/administración & dosificación , Animales , Densidad Ósea/efectos de los fármacos , Densidad Ósea/fisiología , Relación Dosis-Respuesta a Droga , Evaluación Preclínica de Medicamentos/métodos , Femenino , Humanos , Inyecciones Subcutáneas , Interleucina-11/química , Interleucina-11/toxicidad , Hígado/efectos de los fármacos , Hígado/metabolismo , Pulmón/efectos de los fármacos , Pulmón/metabolismo , Macaca fascicularis , Masculino , Polietilenglicoles/química , Polietilenglicoles/toxicidad , Proteínas Recombinantes/administración & dosificación , Proteínas Recombinantes/química , Proteínas Recombinantes/toxicidad
18.
Protein Expr Purif ; 146: 69-77, 2018 06.
Artículo en Inglés | MEDLINE | ID: mdl-29408294

RESUMEN

Current source of recombinant human interleukin-11 (rhIL-11) is isolated from a fusion protein expressed by E. coli that requires additional enterokinase to remove linked protein, resulting in product heterogeneity of N-terminal sequence. Due to lack of glycosylation, rhIL-11 is suitable to be expressed by yeast cells. However, the only available yeast-derived rhIL-11 presents an obstacle in low production yield, as well as an unamiable process, such as the use of reverse-phase chromatography employing plenty of toxic organic solvents. Our findings showed that the low yield was due to self-aggregation of rhIL-11. A novel process recovering bioactive rhIL-11 from the yeast secretory medium therefore has been developed and demonstrated, involving fermentation from Pichia pastoris, followed by a two-phase extraction to precipitate rhIL-11. After renaturing, the protein of interest was purified by a two-column step, comprising a cation-exchanger, and a hydrophobic interaction chromatography in tandem at high sample loads that was facile and cost-effective in future scale-up. Identity and quality assessments confirmed the expected amino acid sequence without N-terminal heterogeneity, as well as high quality in potency and purity. Such a process provides an alternative and adequate supply of the starting material for the PEGylated rhIL-11.


Asunto(s)
Interleucina-11/genética , Pichia/genética , Línea Celular , Proliferación Celular , Cromatografía en Gel , Clonación Molecular/métodos , Fermentación , Expresión Génica , Humanos , Interleucina-11/química , Interleucina-11/aislamiento & purificación , Interleucina-11/metabolismo , Pichia/metabolismo , Agregado de Proteínas , Replegamiento Proteico , Proteínas Recombinantes/química , Proteínas Recombinantes/genética , Proteínas Recombinantes/aislamiento & purificación , Proteínas Recombinantes/metabolismo , Solubilidad
19.
Environ Res ; 167: 567-574, 2018 11.
Artículo en Inglés | MEDLINE | ID: mdl-30165327

RESUMEN

Nonylphenol (NP) and/or bisphenol A (BPA) may have reproductive effects. Although the mechanisms of action remain unclear, steroid hormones biosynthesis, hypothalamus pituitary adrenal axis activity, oxidative stress, and crosstalk interaction of NP and BPA mixture and its pathways may play a contributory role. This cross-sectional study examined whether the interactive effects of NP/BPA and oxidative stress biomarkers played a role in reproductive indices (penis length and anogenital distance (AGD)) in 244 mother-fetus pairs. Four biomarkers of oxidative stress, (8-hydroxy-2'-deoxyguanosine (8-OHdG), 8-nitroguanine (8-NO2Gua), 8-iso-prostaglandin F2α (8-isoPF2α), and 4-hydroxy-2-nonenal-mercapturic acid (HNE-MA)) were simultaneously analyzed using the high-performance liquid chromatography-electrospray ionization tandem mass spectrometry method. No significant associations were found between reproductive indices and NP/BPA or oxidative stress biomarkers. Maternal exposure to a mixture of NP and BPA may enhance 8-OHdG. Interactive effects were found in the high 8-isoPF2α group, and prenatal NP exposure was inversely associated with penis length (ß = -3.68 mm; p = 0.01). Similar results were noted among boys who were born to mothers in the high 8-isoPF2α group, in which BPA was inversely associated with penis length (ß = -4.43 mm; p = 0.005). Our findings suggest important implications for prenatal exposure to oxidative stress, as evidenced by the 8-isoPF2α level. Thus, NP and BPA may interact to shape fetal reproductive tract development, particularly in boys. The interactive effects of NP/BPA, oxidative stress, and reproductive indices should be considered.


Asunto(s)
Compuestos de Bencidrilo/efectos adversos , Genitales Masculinos/anatomía & histología , Estrés Oxidativo , Fenoles/efectos adversos , Estudios Transversales , Femenino , Feto/anatomía & histología , Humanos , Masculino , Embarazo
20.
Artículo en Inglés | MEDLINE | ID: mdl-28533243

RESUMEN

Tigecycline is regarded as a last-resort treatment for carbapenem-resistant Klebsiella pneumoniae (CRKP) infections, but increasing numbers of tigecycline-resistant K. pneumoniae isolates have been reported. The tigecycline resistance mechanisms in CRKP are undetermined. This study aimed to elucidate the mechanisms underlying tigecycline resistance in 16 tigecycline- and carbapenem-resistant K. pneumoniae (TCRKP) isolates. Mutations in tigecycline resistance determinant genes [ramR, acrR, oqxR, tet(A), tet(L), tet(X), tet(M), rpsJ] were assessed by PCR amplicon sequencing, and mutations in ramR and tet(A) exhibited high prevalences individually (81%) and in combination (63%). Eight functional ramR mutation profiles reducing tigecycline sensitivity were verified by plasmid complementation of wild-type and mutant ramR Using a site-specific mutant, the most frequent RamR mutation, A19V (60%), had no significant effect on tigecycline susceptibility or the upregulation of ramA and acrA Two tet(A) variants with double frameshift mutations, type 1 and type 2, were identified; type 2 tet(A) is novel. A parent strain transformed with a plasmid carrying type 1 or type 2 tet(A) increased the tigecycline MIC by 8-fold or 4-fold, respectively. Synergistic effects were observed in strains harboring no ramR gene and a mutated tet(A), with an 8-fold increase in the tigecycline MIC compared with that in strains harboring only mutated tet(A) being seen. Overall, mutations in the ramR and tet(A) efflux genes constituted the major tigecycline resistance mechanisms among the studied TCRKP isolates. The identification of strains exhibiting the combination of a ramR deficiency and widespread mutated tet(A) is concerning due to the possible dissemination of increased tigecycline resistance in K. pneumoniae.


Asunto(s)
Antibacterianos/uso terapéutico , Farmacorresistencia Bacteriana/genética , Klebsiella pneumoniae/efectos de los fármacos , Klebsiella pneumoniae/genética , Proteínas de Transporte de Membrana/genética , Minociclina/análogos & derivados , Proteínas Asociadas a Resistencia a Múltiples Medicamentos/genética , Transactivadores/genética , Enterobacteriaceae Resistentes a los Carbapenémicos/efectos de los fármacos , Enterobacteriaceae Resistentes a los Carbapenémicos/aislamiento & purificación , Carbapenémicos/farmacología , Humanos , Infecciones por Klebsiella/tratamiento farmacológico , Klebsiella pneumoniae/aislamiento & purificación , Pruebas de Sensibilidad Microbiana , Minociclina/uso terapéutico , Mutación/genética , Plásmidos/genética , Resistencia a la Tetraciclina/genética , Tigeciclina
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