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1.
Microb Cell Fact ; 22(1): 238, 2023 Nov 18.
Artículo en Inglés | MEDLINE | ID: mdl-37980525

RESUMEN

BACKGROUND: (Hydroxy)cinnamyl alcohols and allylphenols, including coniferyl alcohol and eugenol, are naturally occurring aromatic compounds widely utilised in pharmaceuticals, flavours, and fragrances. Traditionally, the heterologous biosynthesis of (hydroxy)cinnamyl alcohols from (hydroxy)cinnamic acids involved CoA-dependent activation of the substrate. However, a recently explored alternative pathway involving carboxylic acid reductase (CAR) has proven efficient in generating the (hydroxy)cinnamyl aldehyde intermediate without the need for CoA activation. In this study, we investigated the application of the CAR pathway for whole-cell bioconversion of a range of (hydroxy)cinnamic acids into their corresponding (hydroxy)cinnamyl alcohols. Furthermore, we sought to extend the pathway to enable the production of a variety of allylphenols and allylbenzene. RESULTS: By screening the activity of several heterologously expressed enzymes in crude cell lysates, we identified the combination of Segniliparus rugosus CAR (SrCAR) and Medicago sativa cinnamyl alcohol dehydrogenase (MsCAD2) as the most efficient enzymatic cascade for the two-step reduction of ferulic acid to coniferyl alcohol. To optimise the whole-cell bioconversion in Escherichia coli, we implemented a combinatorial approach to balance the gene expression levels of SrCAR and MsCAD2. This optimisation resulted in a coniferyl alcohol yield of almost 100%. Furthermore, we extended the pathway by incorporating coniferyl alcohol acyltransferase and eugenol synthase, which allowed for the production of eugenol with a titre of up to 1.61 mM (264 mg/L) from 3 mM ferulic acid. This improvement in titre surpasses previous achievements in the field employing a CoA-dependent coniferyl alcohol biosynthesis pathway. Our study not only demonstrated the successful utilisation of the CAR pathway for the biosynthesis of diverse (hydroxy)cinnamyl alcohols, such as p-coumaryl alcohol, caffeyl alcohol, cinnamyl alcohol, and sinapyl alcohol, from their corresponding (hydroxy)cinnamic acid precursors but also extended the pathway to produce allylphenols, including chavicol, hydroxychavicol, and methoxyeugenol. Notably, the microbial production of methoxyeugenol from sinapic acid represents a novel achievement. CONCLUSION: The combination of SrCAR and MsCAD2 enzymes offers an efficient enzymatic cascade for the production of a wide array of (hydroxy)cinnamyl alcohols and, ultimately, allylphenols from their respective (hydroxy)cinnamic acids. This expands the range of value-added molecules that can be generated using microbial cell factories and creates new possibilities for applications in industries such as pharmaceuticals, flavours, and fragrances. These findings underscore the versatility of the CAR pathway, emphasising its potential in various biotechnological applications.


Asunto(s)
Eugenol , Eugenol/metabolismo , Preparaciones Farmacéuticas
2.
J Am Chem Soc ; 144(1): 556-572, 2022 Jan 12.
Artículo en Inglés | MEDLINE | ID: mdl-34941250

RESUMEN

In D4-symmetric tetraoxa[8]circulenes, alternating fused benzene and furan rings form an octagonal array. These compounds are little known despite their novel properties, which include extended planar π-conjugation and a formally antiaromatic cyclooctatetraene core. Tetraoxa[8]circulenes can be formed by acid-induced cyclocondensations of suitable quinones, but existing methods often give very low yields. In addition, π-stacking of simple tetraoxa[8]circulenes reduces solubility and limits opportunities to form homogeneous mixtures or cocrystals with other compounds. To help make tetraoxa[8]circulenes more useful, we have developed better ways to synthesize them, and we have used these methods to produce awkwardly shaped derivatives with large concave electron-rich aromatic surfaces. These compounds crystallize to form open structures that can accommodate various guests, including C60. Analysis of the structures shows that the cyclooctatetraene core of the hosts exhibits surprising variations in C-C bond lengths and conjugation, which appear to be related to the gain or loss of aromaticity. This allows tetraoxa[8]circulenes to serve as sensitive probes of local molecular environment and to be used as sensors of electron-deficient species such as nitroaromatic compounds.

3.
Can J Infect Dis Med Microbiol ; 2022: 4413679, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36437891

RESUMEN

Background: Previous in vitro and in vivo studies indicated that walnut extract has a therapeutic effect on herpes simplex infections. This study aimed to evaluate the efficacy and tolerance of Lazolex® Gel (Iveriapharma, Tbilisi, Georgia), an emollient gel to treat mucocutaneous lesions caused by herpes simplex virus. Methods: A single-center, single-arm, open-label, phase II clinical trial was conducted with 30 patients divided into two groups: 15 patients with herpes simplex virus type 1 (HSV-1) infections and 15 with herpes simplex virus type 2 (HSV-2). All received topical treatment with Lazolex® Gel four times a day for 10 days. The efficacy and tolerance of the treatment were evaluated on day 10 and day 20 of the study. Recurrence rates were also evaluated both prior to treatment with Lazolex® and over a 4-year follow-up period subsequent to treatment. Results: The median effective time to resolution of symptoms (itching, burning, and pain) was 1.97 days in the HSV-1 group and 3.11 days in the HSV-2 group. The median effective time for vesicles and erosion to disappear was 3.64 days in the HSV-1 group and 3.88 days for the HSV-2 group. Finally, the median effective time for inflammatory signs to disappear was 5.70 and 4.32 days, respectively. Following treatment with Lazolex® Gel, the frequency of outbreaks decreased from a median of 2.00 and 1.00 times per year in the HSV-1 and HSV-2 cohorts to 0.25 and 0.00 (p=0.001 and p=0.003), respectively. Conclusions: Topical treatment with Lazolex® Gel applied to lesions four times a day for 10 days was shown to be effective and safe in the treatment of herpes simplex mucocutaneous infections and dramatically reduced the rate of recurrence. Clinical trial was approved by Drug Agency of Ministry of Labour, Health and Social Affairs of Georgia, registration # DA Nº CT-000032, date of approval 01.10.2007.

4.
Appl Microbiol Biotechnol ; 105(13): 5309-5324, 2021 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-34215905

RESUMEN

The xylose oxidative pathway (XOP) has been engineered in microorganisms for the production of a wide range of industrially relevant compounds. However, the performance of metabolically engineered XOP-utilizing microorganisms is typically hindered by D-xylonic acid accumulation. It acidifies the media and perturbs cell growth due to toxicity, thus curtailing enzymatic activity and target product formation. Fortunately, from the growing portfolio of genetic tools, several strategies that can be adapted for the generation of efficient microbial cell factories have been implemented to address D-xylonic acid accumulation. This review centers its discussion on the causes of D-xylonic acid accumulation and how to address it through different engineering and synthetic biology techniques with emphasis given on bacterial strains. In the first part of this review, the ability of certain microorganisms to produce and tolerate D-xylonic acid is also tackled as an important aspect in developing efficient microbial cell factories. Overall, this review could shed some insights and clarity to those working on XOP in bacteria and its engineering for the development of industrially applicable product-specialist strains. KEY POINTS: D-Xylonic acid accumulation is attributed to the overexpression of xylose dehydrogenase concomitant with basal or inefficient expression of enzymes involved in D-xylonic acid assimilation. Redox imbalance and insufficient cofactors contribute to D-xylonic acid accumulation. Overcoming D-xylonic acid accumulation can increase product formation among engineered strains. Engineering strategies involving enzyme engineering, evolutionary engineering, coutilization of different sugar substrates, and synergy of different pathways could potentially address D-xylonic acid accumulation.


Asunto(s)
Ingeniería Metabólica , Xilosa , Bacterias/genética , Medios de Cultivo , Xilosa/análogos & derivados
5.
Appl Microbiol Biotechnol ; 104(5): 2273-2274, 2020 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-31950218

RESUMEN

In the published version, the y-axis data of Fig. 3c was incorrectly inserted (OD600 instead of D-xylonate (g L-1) and the x-axes of Figs. 3b, 3d, 3e and 3f ended at 48 h instead of 72 h. See the correct Fig. 3 below.

6.
Appl Microbiol Biotechnol ; 104(5): 2097-2108, 2020 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-31900554

RESUMEN

The xylose oxidative pathway (XOP) is continuously gaining prominence as an alternative for the traditional pentose assimilative pathways in prokaryotes. It begins with the oxidation of D-xylose to D-xylonic acid, which is further converted to α-ketoglutarate or pyruvate + glycolaldehyde through a series of enzyme reactions. The persistent drawback of XOP is the accumulation of D-xylonic acid intermediate that causes culture media acidification. This study addresses this issue through the development of a novel pH-responsive synthetic genetic controller that uses a modified transmembrane transcription factor called CadCΔ. This genetic circuit was tested for its ability to detect extracellular pH and to control the buildup of D-xylonic acid in the culture media. Results showed that the pH-responsive genetic sensor confers dynamic regulation of D-xylonic acid accumulation, which adjusts with the perturbation of culture media pH. This is the first report demonstrating the use of a pH-responsive transmembrane transcription factor as a transducer in a synthetic genetic circuit that was designed for XOP. This may serve as a benchmark for the development of other genetic controllers for similar pathways that involve acidic intermediates.


Asunto(s)
Medios de Cultivo/química , Escherichia coli/metabolismo , Xilosa/análogos & derivados , Xilosa/metabolismo , Medios de Cultivo/metabolismo , Escherichia coli/genética , Concentración de Iones de Hidrógeno , Oxidación-Reducción
7.
Biotechnol Lett ; 42(11): 2231-2238, 2020 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-32519168

RESUMEN

OBJECTIVE: To identify and characterize a new ß-agarase from Cellulophaga omnivescoria W5C capable of producing biologically-active neoagarooligosaccharides from agar. RESULTS: The ß-agarase, Aga1, has signal peptides on both N- and C-terminals, which are involved in the type IX secretion system. It shares 75% protein sequence identity with AgaD from Zobellia galactanivorans and has a molecular weight of 54 kDa. Biochemical characterization reveals optimum agarolytic activities at pH 7-8 and temperature 30-45 °C. Aga1 retains at least 33% activity at temperatures lower than the sol-gel transition state of agarose. Metal ions are generally not essential, but calcium and potassium enhance its activity whereas iron and zinc are inhibitory. Finally, hydrolysis of agarose with Aga1 yields neoagarotetraose, neoagarohexaose, and neoagarooctaose. CONCLUSIONS: Aga1 displays unique traits such as moderate psychrophilicity, stability, and synergy with other agarases, which makes it an excellent candidate for biosynthetic production of neoagarooligosaccharides from agar.


Asunto(s)
Flavobacteriaceae/enzimología , Glicósido Hidrolasas/genética , Glicósido Hidrolasas/metabolismo , Análisis de Secuencia de ADN/métodos , Proteínas Bacterianas/genética , Proteínas Bacterianas/metabolismo , Clonación Molecular , Flavobacteriaceae/genética , Expresión Génica , Glicósido Hidrolasas/química , Calor , Concentración de Iones de Hidrógeno , Hidrólisis , Peso Molecular , Señales de Clasificación de Proteína , Sefarosa/química
8.
Appl Microbiol Biotechnol ; 103(19): 8063-8074, 2019 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-31482281

RESUMEN

The capability of Escherichia coli to catabolize D-xylonate is a crucial component for building and optimizing the Dahms pathway. It relies on the inherent dehydratase and keto-acid aldolase activities of E. coli. Although the biochemical characteristics of these enzymes are known, their inherent expression regulation remains unclear. This knowledge is vital for the optimization of D-xylonate assimilation, especially in addressing the problem of D-xylonate accumulation, which hampers both cell growth and target product formation. In this report, molecular biology techniques and synthetic biology tools were combined to build a simple genetic switch controller for D-xylonate. First, quantitative and relative expression analysis of the gene clusters involved in D-xylonate catabolism were performed, revealing two D-xylonate-inducible operons, yagEF and yjhIHG. The 5'-flanking DNA sequence of these operons were then subjected to reporter gene assays which showed PyjhI to have low background activity and wide response range to D-xylonate. A PyjhI-driven synthetic genetic switch was then constructed containing feedback control to autoregulate D-xylonate accumulation and to activate the expression of the genes for 1,2,4-butanetriol (BTO) production. The genetic switch effectively reduced D-xylonate accumulation, which led to 31% BTO molar yield, the highest for direct microbial fermentation systems thus far. This genetic switch can be further modified and employed in the production of other compounds from D-xylose through the xylose oxidative pathway.


Asunto(s)
Butanoles/metabolismo , Escherichia coli/genética , Escherichia coli/metabolismo , Regulación Bacteriana de la Expresión Génica/efectos de los fármacos , Ingeniería Metabólica/métodos , Regiones Promotoras Genéticas/efectos de los fármacos , Xilosa/análogos & derivados , Aldehído-Liasas/genética , Aldehído-Liasas/metabolismo , Fusión Artificial Génica , Perfilación de la Expresión Génica , Genes Reporteros , Hidroliasas/genética , Hidroliasas/metabolismo , Xilosa/metabolismo
10.
J Ind Microbiol Biotechnol ; 46(2): 159-169, 2019 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-30554290

RESUMEN

The non-conventional D-xylose metabolism called the Dahms pathway which only requires the expression of at least three enzymes to produce pyruvate and glycolaldehyde has been previously engineered in Escherichia coli. Strains that rely on this pathway exhibit lower growth rates which were initially attributed to the perturbed redox homeostasis as evidenced by the lower intracellular NADPH concentrations during exponential growth phase. NADPH-regenerating systems were then tested to restore the redox homeostasis. The membrane-bound pyridine nucleotide transhydrogenase, PntAB, was overexpressed and resulted to a significant increase in biomass and glycolic acid titer and yield. Furthermore, expression of PntAB in an optimized glycolic acid-producing strain improved the growth and product titer significantly. This work demonstrated that compensating for the NADPH demand can be achieved by overexpression of PntAB in E. coli strains assimilating D-xylose through the Dahms pathway. Consequently, increase in biomass accumulation and product concentration was also observed.


Asunto(s)
Escherichia coli/metabolismo , Glicolatos/metabolismo , NADP Transhidrogenasas/metabolismo , Escherichia coli/genética , Proteínas de Escherichia coli/genética , Proteínas de Escherichia coli/metabolismo , Regulación Bacteriana de la Expresión Génica , NADP/genética , NADP/metabolismo , NADP Transhidrogenasas/genética , Xilosa/metabolismo
11.
Virol J ; 15(1): 190, 2018 12 14.
Artículo en Inglés | MEDLINE | ID: mdl-30547827

RESUMEN

BACKGROUND: African swine fever virus (ASFV) causes an acute hemorrhagic infection in suids with a mortality rate of up to 100%. No vaccine is available and the potential for catastrophic disease in Europe remains elevated due to the ongoing ASF epidemic in Russia and Baltic countries. To date, intra-epidemic whole-genome variation for ASFV has not been reported. To provide a more comprehensive baseline for genetic variation early in the ASF outbreak, we sequenced two Georgian ASFV samples, G-2008/1 and G-2008/2, derived from domestic porcine blood collected in 2008. METHODS: Genomic DNA was extracted directly from low-volume ASFV PCR-positive porcine blood samples and subjected to next generation sequencing on the Illumina Miseq platform. De novo and mapped sequence assemblies were performed using CLCBio software. Genomic illustrations, sequence alignments and assembly figures were generated using Geneious v10.2.4. Sequence repeat architecture was analyzed using DNASTAR GeneQuest 14.1.0. RESULTS: The G-2008/1 and G-2008/2 genomes were distinguished from each other by coding changes in seven genes, including MGF 110-1 L, X69R, MGF 505-10R, EP364R, H233R, E199L, and MGF 360-21R in addition to eight homopolymer tract variations. The 2008/2 genome possessed a novel allele state at a previously undescribed intergenic repeat locus between genes C315R and C147L. The C315R/C147L locus represents the earliest observed variable repeat sequence polymorphism reported among isolates from this epidemic. No sequence variation was observed in conventional ASFV subtyping markers. The two genomes exhibited complete collinearity and identical gene content with the Georgia 2007/1 reference genome. Approximately 56 unique homopolymer A/T-tract variations were identified that were unique to the Georgia 2007/1 genome. In both 2008 genomes, within-sample sequence read heterogeneity was evident at six homopolymeric G/C-tracts confined to the known hypervariable ~ 7 kb region in the left terminal region of the genome. CONCLUSIONS: This is the first intra-epidemic comparative genomic analysis reported for ASFV and provides insight into the intra-epidemic microevolution of ASFV. The genomes reported here, in addition to the G-2007/1 genome, provide an early baseline for future genome-level comparisons and epidemiological tracing efforts.


Asunto(s)
Virus de la Fiebre Porcina Africana/genética , Fiebre Porcina Africana/epidemiología , ADN Viral/sangre , Genoma Viral/genética , Polimorfismo Genético/genética , Animales , Secuencia de Bases , ADN Viral/genética , Brotes de Enfermedades , Georgia (República)/epidemiología , Secuenciación de Nucleótidos de Alto Rendimiento , Alineación de Secuencia , Análisis de Secuencia de ADN , Porcinos , Proteínas Virales/genética
12.
Appl Microbiol Biotechnol ; 102(5): 2179-2189, 2018 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-29392388

RESUMEN

Glycolic acid (GA) is an ⍺-hydroxy acid used in cosmetics, packaging, and medical industries due to its excellent properties, especially in its polymeric form. In this study, Escherichia coli was engineered to produce GA from D-xylose by linking the Dahms pathway, the glyoxylate bypass, and the partial reverse glyoxylate pathway (RGP). Initially, a GA-producing strain was constructed by disrupting the xylAB and glcD genes in the E. coli genome and overexpressing the xdh(Cc) from Caulobacter crescentus. This strain was further improved through modular optimization of the Dahms pathway and the glyoxylate bypass. Results for module 1 showed that the rate-limiting step of the Dahms pathway was the xylonate dehydratase reaction, and the overexpression of yagF was sufficient to overcome this bottleneck. Furthermore, the appropriate aldolase gene for module 1 was proven to be yagE. The results also show that overexpression of the lactaldehyde dehydrogenase gene, aldA, is needed to increase the GA production while the overexpression of glyoxylate reductase gene, ycdW, was only essential when the glyoxylate bypass was active. On the other hand, the module 2 enzymes AceA and AceK were vital in activating the glyoxylate bypass, while the RGP enzymes were dispensable. The final strain (GA19) produced 4.57 g/L GA with a yield of 0.46 g/g from D-xylose. So far, this is the highest value achieved for GA production in engineered E. coli through the Dahms pathway.


Asunto(s)
Escherichia coli/metabolismo , Glicolatos/metabolismo , Glioxilatos/metabolismo , Ingeniería Metabólica , Xilosa/metabolismo , Oxidorreductasas de Alcohol/genética , Oxidorreductasas de Alcohol/metabolismo , Aldehído-Liasas/genética , Aldehído-Liasas/metabolismo , Escherichia coli/enzimología , Escherichia coli/genética , Hidroliasas/genética , Hidroliasas/metabolismo , Fosfotransferasas (Aceptor de Grupo Alcohol)/genética , Fosfotransferasas (Aceptor de Grupo Alcohol)/metabolismo
13.
Appl Microbiol Biotechnol ; 102(18): 7703-7716, 2018 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-30003296

RESUMEN

The D-xylose oxidative pathway (XOP) has recently been employed in several recombinant microorganisms for growth or for the production of several valuable compounds. The XOP is initiated by D-xylose oxidation to D-xylonolactone, which is then hydrolyzed into D-xylonic acid. D-Xylonic acid is then dehydrated to form 2-keto-3-deoxy-D-xylonic acid, which may be further dehydrated then oxidized into α-ketoglutarate or undergo aldol cleavage to form pyruvate and glycolaldehyde. This review introduces a brief discussion about XOP and its discovery in bacteria and archaea, such as Caulobacter crescentus and Haloferax volcanii. Furthermore, the current advances in the metabolic engineering of recombinant strains employing the XOP are discussed. This includes utilization of XOP for the production of diols, triols, and short-chain organic acids in Escherichia coli, Saccharomyces cerevisiae, and Corynebacterium glutamicum. Improving the D-xylose uptake, growth yields, and product titer through several metabolic engineering techniques bring some of these recombinant strains close to industrial viability. However, more developments are still needed to optimize the XOP pathway in the host strains, particularly in the minimization of by-product formation.


Asunto(s)
Archaea/metabolismo , Bacterias/metabolismo , Ingeniería Metabólica , Recombinación Genética , Xilosa/metabolismo , Levaduras/metabolismo , Archaea/genética , Bacterias/genética , Oxidación-Reducción , Levaduras/genética
14.
Curr Microbiol ; 75(7): 925-933, 2018 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-29536113

RESUMEN

The continued research in the isolation of novel bacterial strains is inspired by the fact that native microorganisms possess certain desired phenotypes necessary for recombinant microorganisms in the biotech industry. Most studies have focused on the isolation and characterization of strains from marine ecosystems as they present a higher microbial diversity than other sources. In this study, a marine bacterium, W5C, was isolated from red seaweed collected from Yeosu, South Korea. The isolate can utilize several natural polysaccharides such as agar, alginate, carrageenan, and chitin. Genome sequence and comparative genomics analyses suggest that strain W5C belongs to a novel species of the Cellulophaga genus, from which the name Cellulophaga omnivescoria sp. nov. is proposed. Its genome harbors 3,083 coding sequences and 146 carbohydrate-active enzymes (CAZymes). Compared to other reported Cellulophaga species, the genome of W5C contained a higher proportion of CAZymes (4.7%). Polysaccharide utilization loci (PUL) for agar, alginate, and carrageenan were identified in the genome, along with other several putative PULs. These PULs are excellent sources for discovering novel hydrolytic enzymes and pathways with unique characteristics required for biorefinery applications, particularly in the utilization of marine renewable biomass. The type strain is JCM 32108T (= KCTC 13157BPT).


Asunto(s)
Flavobacteriaceae/metabolismo , Genoma Bacteriano , Polisacáridos/metabolismo , Agua de Mar/microbiología , Sefarosa/metabolismo , Biodegradación Ambiental , Flavobacteriaceae/clasificación , Flavobacteriaceae/genética , Flavobacteriaceae/aislamiento & purificación , Filogenia , República de Corea , Agua de Mar/química
15.
Artículo en Inglés | MEDLINE | ID: mdl-29035626

RESUMEN

The feasibility of open-pore polyurethane (PU) foam as packing material for wet chemical scrubber was tested for NH3 and H2S removals. The foam is inexpensive, light-weight, highly porous (low pressure drop) and provides large surface area per unit volume, which are desirable properties for enhanced gas/liquid mass transfer. Conventional HCl/HOCl (for NH3) and NaOH/NaOCl (for H2S) scrubbing solutions were used to absorb and oxidize the gases. Assessment of the wet chemical scrubbers reveals that pH and ORP levels are important to maintain the gas removal efficiencies >95%. A higher re-circulation rate of scrubbing solutions also proved to enhance the performance of the NH3 and H2S columns. Accumulation of salts was confirmed by the gradual increase in total dissolved solids and conductivity values of scrubbing solutions. The critical elimination capacities at >95% gas removals were found to be 5.24 g NH3-N/m3-h and 17.2 g H2S-S/m3-h at an empty bed gas residence time of 23.6 s. Negligible pressure drops (< 4 mm H2O) after continuous operation demonstrate the suitability of PU as a practical packing material in wet chemical scrubbers for NH3 and H2S removals from high-volume dilute emissions.


Asunto(s)
Contaminantes Atmosféricos/química , Contaminación del Aire/prevención & control , Amoníaco/química , Gases/química , Sulfuro de Hidrógeno/química , Poliuretanos/metabolismo , Adsorción , Contaminantes Atmosféricos/metabolismo , Amoníaco/metabolismo , Filtración , Gases/metabolismo , Humanos , Sulfuro de Hidrógeno/metabolismo , Odorantes/prevención & control , Poliuretanos/química
16.
Artículo en Inglés | MEDLINE | ID: mdl-29842847

RESUMEN

Monitoring and control of odorous compound emissions have been enforced by the Korean government since 2005. One of the point sources for these emissions was from food waste composting facilities. In this study, a pilot-scale scrubber installed in a composting facility was evaluated for its performance in the removal of malodorous compounds. The exhaust stream contained ammonia and methylamine as the major odorants detected by the threshold odor test and various instrumental techniques (GC-FID, FPD, MS and HPLC/UV). For the scrubber operation, the column was randomly packed with polypropylene Hi-Rex 200, while aqueous sulfuric acid was selected as the scrubbing solution. To achieve 95% removal, the scrubber must be operated by using H2SO4 solution with pH at < 6.5, liquid to gas ratio > 4.5, gas loading rate < 1750 m3/m3-hr and contact time < 0.94 s. The scrubber performance was further evaluated by determining the mass transfer coefficients and then monitoring for 355 days of operation. The pilot-scale scrubber maintained > 95% ammonia and methylamine removal efficiencies despite the fluctuations in the inlet (from composting facility exhaust stream) concentration. The optimum operating conditions and scrubber performance indicators determined in this study provides a basis for the design of a plant-scale scrubber for treatment of composting facility gas emissions.


Asunto(s)
Compostaje , Alimentos , Odorantes , Eliminación de Residuos , Compuestos Orgánicos Volátiles/aislamiento & purificación , Instalaciones de Eliminación de Residuos/instrumentación , Amoníaco/química , Cromatografía de Gases , Compostaje/instrumentación , Compostaje/métodos , Humanos , Odorantes/prevención & control , Proyectos Piloto , Eliminación de Residuos/instrumentación , Eliminación de Residuos/métodos , República de Corea , Ácidos Sulfúricos/aislamiento & purificación
17.
Pediatr Allergy Immunol ; 28(8): 810-817, 2017 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-28981980

RESUMEN

BACKGROUND: Airway epithelial cells (AEC) are quite difficult to access in newborns and infants. It is critically important to develop robust life-extended models to conduct translational studies in this age group. We propose the use of a recently described cell culture technology (conditionally reprogrammed cells-CRC) to generate continuous primary cell cultures from nasal and bronchial AEC of young children. METHODS: We collected nasal and/or bronchial AEC from a total of 23 subjects of different ages including newborns/infants/toddlers (0-2 years; N = 9), school-age children (4-11 years; N = 6), and a group of adolescent/adult donors (N = 8). For CRC generation, we used conditioned medium from mitotically inactivated 3T3 fibroblasts and Rho-associated kinase (ROCK) inhibitor (Y-27632). Antiviral immune responses were studied using 25 key antiviral genes and protein production of type III epithelial interferon (IFN λ1) after double-stranded (ds) RNA exposure. RESULTS: CRC derived from primary AEC of neonates/infants and young children exhibited: (i) augmented proliferative capacity and life extension, (ii) preserved airway epithelial phenotype after multiple passages, (iii) robust immune responses characterized by the expression of innate antiviral genes and parallel nasal/bronchial production of IFN λ1 after exposure to dsRNA, and (iv) induction of airway epithelial inflammatory and remodeling responses to dsRNA (eg, CXCL8 and MMP9). CONCLUSION: Conditional reprogramming of AEC from young children is a feasible and powerful translational approach to investigate early-life airway epithelial immune responses in humans.


Asunto(s)
Células Epiteliales/inmunología , Cultivo Primario de Células/métodos , Mucosa Respiratoria/citología , Adolescente , Adulto , Biomarcadores/metabolismo , Proliferación Celular , Células Cultivadas , Niño , Preescolar , Citocinas/metabolismo , Células Epiteliales/fisiología , Células Epiteliales/virología , Estudios de Factibilidad , Femenino , Humanos , Lactante , Recién Nacido , Masculino , Mucosa Respiratoria/inmunología , Mucosa Respiratoria/metabolismo , Mucosa Respiratoria/virología , Enfermedades Respiratorias/inmunología , Enfermedades Respiratorias/virología
18.
Mol Biol Rep ; 44(4): 315-321, 2017 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-28685248

RESUMEN

Epidemiological genetics established that heritability in determining the risk of myocardial infarction (MI) is substantially greater when MI occurs early in life. However, the genetic architecture of early-onset and late-onset MI was not compared. We analyzed genotype frequencies of SNPs in/near 20 genes whose protein products are involved in the pathogenesis of atherosclerosis in two groups of Russian patients with MI: the first group included patients with age of first MI onset <60 years (N = 230) and the second group with onset ≥60 years (N = 174). The control group of corresponding ethnicity consisted of 193 unrelated volunteers without cardiovascular diseases (93 individuals were over 60 years). We found that in the group of patients with age of onset <60 years, SNPs FGB rs1800788*T, TGFB1 rs1982073*T/T, ENOS rs2070744*C and CRP rs1130864*T/T were associated with risk of MI, whereas in patients with age of onset ≥60 years, only TGFB1 rs1982073*T/T was associated with risk of MI. Using APSampler software, we found composite markers associated with MI only in patients with early onset: FGB rs1800788*T + TGFB1 rs1982073*T; FGB rs1800788*T + LPL rs328*C + IL4 rs2243250*C; FGB rs1800788*T + ENOS rs2070744*C (Fisher p values of 1.4 × 10-6 to 2.2 × 10-5; the permutation p values of 1.1 × 10-5 to 3.0 × 10-4; ORs = 2.67-2.54). Alleles included in the combinations were associated with MI less significantly and with lower ORs than the combinations themselves. The result showed a substantially greater contribution of the genetic component in the development of MI if it occurs early in life, and demonstrated the usefulness of genetic testing for young people.


Asunto(s)
Aterosclerosis/genética , Infarto del Miocardio/genética , Adulto , Factores de Edad , Anciano , Anciano de 80 o más Años , Alelos , Biomarcadores/sangre , Femenino , Frecuencia de los Genes/genética , Estudios de Asociación Genética , Predisposición Genética a la Enfermedad/genética , Humanos , Masculino , Persona de Mediana Edad , Infarto del Miocardio/epidemiología , Polimorfismo de Nucleótido Simple/genética , Factores de Riesgo , Federación de Rusia
19.
Am J Physiol Endocrinol Metab ; 309(2): E168-76, 2015 Jul 15.
Artículo en Inglés | MEDLINE | ID: mdl-26015434

RESUMEN

We investigated the separate and combined effects of hyperglycemia and hyperinsulinemia on markers of endothelial function, proinflammatory and proatherothrombotic responses in overweight/obese nondiabetic humans. Twenty-two individuals (13 F/9 M, BMI 30.1 ± 4.1 kg/m(2)) were studied during four randomized, single-blind protocols. The pancreatic clamp technique was combined with 4-h glucose clamps consisting of either 1) euinsulinemia-euglycemia, 2) euinsulinemia-hyperglycemia, 3) hyperinsulinemia-hyperglycemia, or 4) hyperinsulinemia-euglycemia. Insulin levels were higher (998 ± 66 vs. 194 ± 22 pmol/l) during hyperinsulinemia compared with euinsulinemia. Glucose levels were 11.1 mmol/l during hyperinsulinemia compared with 5.1 ± 0.1 mmol/l during euglycemia. VCAM, ICAM, P-selectin, E-selectin, IL-6, adiponectin, and PAI-1 responses were all increased (P < 0.01-0.0001), and endothelial function was decreased (P < 0.0005) during euinsulinemia-hyperglycemia compared with other protocols. Hyperinsulinemia in the presence of hyperglycemia prevented the increase in proinflammatory and proatherothrombotic markers while also normalizing vascular endothelial function. We conclude that 4 h of moderate hyperglycemia can result in increases of proinflammatory markers (ICAM, VCAM, IL-6, E-selectin), platelet activation (P-selectin), reduced fibrinolytic balance (increased PAI-1), and disordered endothelial function in a group of obese and overweight individuals. Hyperinsulinemia prevents the actions of moderate hyperglycemia to reduce endothelial function and increase proinflammatory and proatherothrombotic markers.


Asunto(s)
Biomarcadores/sangre , Endotelio Vascular/fisiopatología , Hiperglucemia/sangre , Hiperinsulinismo/sangre , Mediadores de Inflamación/sangre , Obesidad , Sobrepeso , Vasculitis/sangre , Adulto , Glucemia/fisiología , Femenino , Técnica de Clampeo de la Glucosa , Humanos , Hiperglucemia/complicaciones , Hiperinsulinismo/complicaciones , Insulina/sangre , Masculino , Obesidad/sangre , Obesidad/fisiopatología , Sobrepeso/sangre , Sobrepeso/fisiopatología , Vasculitis/complicaciones
20.
Respir Res ; 16: 132, 2015 Oct 29.
Artículo en Inglés | MEDLINE | ID: mdl-26511361

RESUMEN

BACKGROUND: Mitotic synchrony is the synchronous progression of a population of cells through the cell cycle and is characteristic of non-diseased airway epithelial cells. However, we previously showed that asthmatic airway epithelial cells are characterized by mitotic asynchrony and are pro-inflammatory as a result. Glucocorticoids can induce mitotic synchrony that in turn suppresses the pro-inflammatory state of diseased cells, suggesting a novel anti-inflammatory mechanism of action. Herein, we benchmarked traditional glucocorticoids against the ability of a new clinical-stage dissociative steroidal drug, VBP15, for mitotic resynchronization and associated anti-inflammatory activity in asthmatic airway epithelial cells. METHODS: Primary airway epithelial cells differentiated at air-liquid interface were exposed to VBP15, dexamethasone or vehicle following in vitro mechanical injury. Basolateral cytokine secretions (TGF-ß1, IL-6, IL-10, IL-13, and IL-1ß) were analyzed at different time points using cytometric bead assays and mitosis was examined by flow cytometry. RESULTS: VBP15 improved mitotic synchrony of proliferating asthmatic cells in air-liquid interface cultures compared to vehicle-exposed cultures. VBP15 also significantly reduced the basolateral secretion of pro-inflammatory (i.e. IL-1ß) and pro-fibrogenic cytokines (i.e. TGF-ß1) in air-liquid interface-differentiated asthmatic epithelial cultures following mechanical injury. CONCLUSION: VBP15 improves mitotic asynchrony and injury-induced pro-inflammatory and fibrogenic responses in asthmatic airway epithelial cultures with efficacy comparable to traditional glucocorticoids. As it is predicted to show superior side effect profiles compared to traditional glucocorticoids, VBP15 holds potential for treatment of asthma and other respiratory conditions.


Asunto(s)
Antiinflamatorios/farmacología , Asma/tratamiento farmacológico , Dexametasona/farmacología , Células Epiteliales/efectos de los fármacos , Glucocorticoides/farmacología , Pulmón/efectos de los fármacos , Mitosis/efectos de los fármacos , Pregnadienodioles/farmacología , Asma/metabolismo , Asma/patología , Estudios de Casos y Controles , Células Cultivadas , Citocinas/metabolismo , Células Epiteliales/patología , Humanos , Mediadores de Inflamación/metabolismo , Pulmón/metabolismo , Pulmón/patología , Fibrosis Pulmonar/metabolismo , Fibrosis Pulmonar/patología , Fibrosis Pulmonar/prevención & control , Factores de Tiempo
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