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1.
Int J Med Sci ; 21(9): 1681-1688, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39006850

RESUMEN

Hypertension affects a large number of individuals globally and is a common cause of nephropathy, stroke, ischaemic heart disease and other vascular diseases. While many anti-hypertensive medications are used safely and effectively in clinic practice, controlling hypertensive complications solely by reducing blood pressure (BP) can be challenging. α-Mangostin, a xanthone molecule extracted from the pericarp of Garcinia mangostana L., has shown various beneficial effects such as anti-tumor, anti-hyperuricemia, and anti-inflammatory properties. However, the effects of α-Mangostin on hypertension remain unknown. In this study, we observed that α-Mangostin significantly decreased systolic and diastolic blood pressure in spontaneously hypertensive rats (SHR), possibly through the down-regulation of angiotensin II (Ang II). We also identified early markers of hypertensive nephropathy, including urinary N-acetyl-ß-D-glucosaminidase (NAG) and ß2-microglobulin (ß2-MG), which were reduced by α-Mangostin treatment. Mechanistic studies suggested that α-Mangostin may inhibit renal tubular epithelial-to-mesenchymal transformation (EMT) by down-regulating the TGF-ß signaling pathway, thus potentially offering a new therapeutic approach for hypertension and hypertensive nephropathy.


Asunto(s)
Angiotensina II , Presión Sanguínea , Transición Epitelial-Mesenquimal , Hipertensión , Xantonas , Animales , Humanos , Masculino , Ratas , Angiotensina II/metabolismo , Antihipertensivos/farmacología , Antihipertensivos/uso terapéutico , Presión Sanguínea/efectos de los fármacos , Línea Celular , Transición Epitelial-Mesenquimal/efectos de los fármacos , Fibrosis/tratamiento farmacológico , Garcinia mangostana/química , Hipertensión/tratamiento farmacológico , Hipertensión/patología , Hipertensión Renal/tratamiento farmacológico , Hipertensión Renal/patología , Nefritis , Ratas Endogámicas SHR , Transducción de Señal/efectos de los fármacos , Xantonas/farmacología , Xantonas/uso terapéutico
2.
J Nat Prod ; 86(1): 24-33, 2023 01 27.
Artículo en Inglés | MEDLINE | ID: mdl-36634312

RESUMEN

Hyperuricemia is the result of overproduction and/or underexcretion of uric acid, and it is a well-known risk factor for gout, hypertension, and diabetes. However, available drugs for hyperuricemia in the clinic are limited. Recently, a lot of research has been conducted in order to discover new uric acid-lowering agents from plants and foods. We found that the extracts from the pericarp of mangosteen reduced urate. Bioactivity-guided study showed that α-mangostin was the principal constituent. Herein, we reported for the first time the hypouricemic activities and underling mechanism of α-mangostin. The α-mangostin dose- and time-dependently decreased the levels of serum urate in hyperuricemic mice and markedly increased the clearance of urate in hyperuricemic rats, exhibiting a promotion of urate excretion in the kidney. Further evidence showed that α-mangostin significantly decreased the protein levels of GLUT9 in the kidneys. The change in the expression of URAT1 was not observed. Moreover, α-mangostin did not inhibit the activities of xanthine oxidoreductase and uricase in vitro or in vivo. Taken together, these findings suggest that α-mangostin has potential to be developed as a new anti-hyperuricemic agent with promoting uric acid excretion.


Asunto(s)
Garcinia mangostana , Hiperuricemia , Ratas , Ratones , Animales , Hiperuricemia/tratamiento farmacológico , Hiperuricemia/metabolismo , Ácido Úrico/metabolismo , Xantina Oxidasa , Riñón/metabolismo
3.
PLoS Pathog ; 16(5): e1008423, 2020 05.
Artículo en Inglés | MEDLINE | ID: mdl-32365143

RESUMEN

Post-transcriptional regulation via small regulatory RNAs (sRNAs) has been implicated in diverse regulatory processes in bacteria, including virulence. One class of sRNAs, termed trans-acting sRNAs, can affect the stability and/or the translational efficiency of regulated transcripts. In this study, we utilized a collaborative approach that employed data from infection with the Borrelia burgdorferi Tn library, coupled with Tn-seq, together with borrelial sRNA and total RNA transcriptomes, to identify an intergenic trans-acting sRNA, which we designate here as ittA for infectivity-associated and tissue-tropic sRNA locus A. The genetic inactivation of ittA resulted in a significant attenuation in infectivity, with decreased spirochetal load in ear, heart, skin and joint tissues. In addition, the ittA mutant did not disseminate to peripheral skin sites or heart tissue, suggesting a role for ittA in regulating a tissue-tropic response. RNA-Seq analysis determined that 19 transcripts were differentially expressed in the ittA mutant relative to its genetic parent, including vraA, bba66, ospD and oms28 (bba74). Subsequent proteomic analyses also showed a significant decrease of OspD and Oms28 (BBA74) proteins. To our knowledge this is the first documented intergenic sRNA that alters the infectivity potential of B. burgdorferi.


Asunto(s)
Borrelia burgdorferi/genética , ARN Pequeño no Traducido/metabolismo , Tropismo/genética , Borrelia burgdorferi/metabolismo , Borrelia burgdorferi/patogenicidad , Regulación Bacteriana de la Expresión Génica/genética , Biblioteca de Genes , Genoma Bacteriano , Enfermedad de Lyme/microbiología , Proteómica , ARN Bacteriano/genética , ARN Pequeño no Traducido/genética , Transcriptoma/genética , Virulencia
4.
PLoS Pathog ; 15(5): e1007644, 2019 05.
Artículo en Inglés | MEDLINE | ID: mdl-31086414

RESUMEN

Borrelia burgdorferi, the causative agent of Lyme disease in humans, is maintained in a complex biphasic life cycle, which alternates between tick and vertebrate hosts. To successfully survive and complete its enzootic cycle, B. burgdorferi adapts to diverse hosts by regulating genes required for survival in specific environments. Here we describe the first ever use of transposon insertion sequencing (Tn-seq) to identify genes required for B. burgdorferi survival in its tick host. We found that insertions into 46 genes resulted in a complete loss of recovery of mutants from larval Ixodes ticks. Insertions in an additional 56 genes resulted in a >90% decrease in fitness. The screen identified both previously known and new genes important for larval tick survival. Almost half of the genes required for survival in the tick encode proteins of unknown function, while a significant portion (over 20%) encode membrane-associated proteins or lipoproteins. We validated the results of the screen for five Tn mutants by performing individual competition assays using mutant and complemented strains. To better understand the role of one of these genes in tick survival, we conducted mechanistic studies of bb0017, a gene previously shown to be required for resistance against oxidative stress. In this study we show that BB0017 affects the regulation of key borrelial virulence determinants. The application of Tn-seq to in vivo screening of B. burgdorferi in its natural vector is a powerful tool that can be used to address many different aspects of the host pathogen interaction.


Asunto(s)
Proteínas Bacterianas/genética , Borrelia burgdorferi/crecimiento & desarrollo , Elementos Transponibles de ADN , Regulación Bacteriana de la Expresión Génica , Enfermedad de Lyme/microbiología , Garrapatas/crecimiento & desarrollo , Factores de Virulencia/genética , Animales , Proteínas Bacterianas/metabolismo , Borrelia burgdorferi/genética , Borrelia burgdorferi/inmunología , Modelos Animales de Enfermedad , Vectores de Enfermedades , Secuenciación de Nucleótidos de Alto Rendimiento , Interacciones Huésped-Patógeno , Enfermedad de Lyme/inmunología , Ratones , Garrapatas/microbiología , Factores de Virulencia/metabolismo
5.
Microbiology (Reading) ; 166(10): 988-994, 2020 10.
Artículo en Inglés | MEDLINE | ID: mdl-32936070

RESUMEN

Borrelia burgdorferi, a causative agent of Lyme disease, encodes a protein BBB07 on the genomic plasmid cp26. BBB07 was identified as a candidate integrin ligand based on the presence of an RGD tripeptide motif, which is present in a number of mammalian ligands for ß1 and ß3 integrins . Previous work demonstrated that BBB07 in recombinant form binds to ß1 integrins and induces inflammatory responses in synovial cells in culture. Several transposon mutants in bbb07 were attenuated in an in vivo screen of the transposon library in mice. We therefore tested individual transposon mutant clones in single-strain infections in mice and found that they were attenuated in terms of ID50 but did not have significantly reduced tissue burdens in mice. Based on data presented here we conclude that BBB07 is not essential for, but does contribute to, B. burgdorferi infectivity in mice.


Asunto(s)
Proteínas Bacterianas/metabolismo , Borrelia burgdorferi/metabolismo , Enfermedad de Lyme/microbiología , Animales , Carga Bacteriana , Proteínas Bacterianas/genética , Borrelia burgdorferi/genética , Biblioteca de Genes , Enfermedad de Lyme/patología , Ratones , Ratones Endogámicos C3H , Mutación
6.
Biol Pharm Bull ; 43(11): 1653-1659, 2020 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-32863294

RESUMEN

Hyperuricemia is mainly the result of relative underexcretion of urate. Urate is mainly eliminated by kidney and several important transporters expressed on the membrane of renal tubular cells involved in urate excretion. Olsalazine sodium was screened from 3167 authorized small compounds/drugs, targeting xanthine oxidoreductase. In previous study, we reported that olsalazine sodium significantly reduced the serum urate levels, and the anti-hyperuricemic activity linked with inhibiting urate formation by reducing the activity of xanthine oxidoreductase. The current research aimed to assess olsalazine sodium renal urate excretion and likely molecular mechanism. The results showed that administration of olsalazine sodium 5.0 mg/kg decreased the levels of serum urate in hyperuricemic rats, and noticeably improved the fractional excretion of urate and urate clearance, exhibiting an uricosuric action. Moreover, olsalazine sodium (2.5, 5.0, 10.0 mg/kg) reduced the level of blood urea nitrogen in rats. Further study showed that olsalazine sodium reduced the mRNA expression of urate reabsorptive transporter glucose transporter 9 (GLUT9), increased the mRNA expression of urate secretory transporters, organic anion transporter 1 (OAT1), OAT3 and type 1 sodium-dependent phosphate transporter (NPT1) as well as the protein expression of OAT3 in the kidney in hyperuricemic mice. In conclusion, olsalazine sodium exhibited a promotion of urate excretion in kidney by increasing the expression of OAT3.


Asunto(s)
Ácidos Aminosalicílicos/farmacología , Hiperuricemia/tratamiento farmacológico , Transportadores de Anión Orgánico Sodio-Independiente/agonistas , Eliminación Renal/efectos de los fármacos , Ácido Úrico/metabolismo , Ácidos Aminosalicílicos/uso terapéutico , Animales , Nitrógeno de la Urea Sanguínea , Creatinina/sangre , Creatinina/orina , Modelos Animales de Enfermedad , Relación Dosis-Respuesta a Droga , Proteínas Facilitadoras del Transporte de la Glucosa/antagonistas & inhibidores , Proteínas Facilitadoras del Transporte de la Glucosa/metabolismo , Humanos , Hiperuricemia/sangre , Hiperuricemia/fisiopatología , Hiperuricemia/orina , Túbulos Renales Proximales/efectos de los fármacos , Túbulos Renales Proximales/metabolismo , Túbulos Renales Proximales/fisiopatología , Masculino , Ratones , Proteínas de Transporte de Monosacáridos/antagonistas & inhibidores , Proteínas de Transporte de Monosacáridos/metabolismo , Proteína 1 de Transporte de Anión Orgánico/agonistas , Proteína 1 de Transporte de Anión Orgánico/metabolismo , Transportadores de Anión Orgánico Sodio-Independiente/metabolismo , Ratas , Ratas Sprague-Dawley , Eliminación Renal/fisiología , Reabsorción Renal/efectos de los fármacos , Reabsorción Renal/fisiología , Proteínas Cotransportadoras de Sodio-Fosfato de Tipo I/agonistas , Proteínas Cotransportadoras de Sodio-Fosfato de Tipo I/metabolismo , Ácido Úrico/sangre , Ácido Úrico/orina
7.
PLoS Pathog ; 13(2): e1006225, 2017 02.
Artículo en Inglés | MEDLINE | ID: mdl-28212410

RESUMEN

Borrelia burgdorferi, the causative agent of Lyme disease in humans, is exposed to reactive oxygen and nitrogen species (ROS and RNS) in both the tick vector and vertebrate reservoir hosts. B. burgdorferi contains a limited repertoire of canonical oxidative stress response genes, suggesting that novel gene functions may be important for protection of B. burgdorferi against ROS or RNS exposure. Here, we use transposon insertion sequencing (Tn-seq) to conduct an unbiased search for genes involved in resistance to nitric oxide, hydrogen peroxide, and tertiary-butyl hydroperoxide in vitro. The screens identified 66 genes whose disruption resulted in increased susceptibility to at least one of the stressors. These genes include previously characterized mediators of ROS and RNS resistance (including components of the nucleotide excision repair pathway and a subunit of a riboflavin transporter), as well as novel putative resistance candidates. DNA repair mutants were among the most sensitive to RNS in the Tn-seq screen, and survival assays with individual Tn mutants confirmed that the putative ribonuclease BB0839 is involved in resistance to nitric oxide. In contrast, mutants lacking predicted inner membrane proteins or transporters were among the most sensitive to ROS, and the contribution of three such membrane proteins (BB0017, BB0164, and BB0202) to ROS sensitivity was confirmed using individual Tn mutants and complemented strains. Further analysis showed that levels of intracellular manganese are significantly reduced in the Tn::bb0164 mutant, identifying a novel role for BB0164 in B. burgdorferi manganese homeostasis. Infection of C57BL/6 and gp91phox-/- mice with a mini-library of 39 Tn mutants showed that many of the genes identified in the in vitro screens are required for infectivity in mice. Collectively, our data provide insight into how B. burgdorferi responds to ROS and RNS and suggests that this response is relevant to the in vivo success of the organism.


Asunto(s)
Borrelia burgdorferi/genética , Borrelia burgdorferi/inmunología , Genes Bacterianos/inmunología , Enfermedad de Lyme/microbiología , Animales , Modelos Animales de Enfermedad , Secuenciación de Nucleótidos de Alto Rendimiento , Enfermedad de Lyme/inmunología , Ratones , Ratones Endogámicos C57BL , Reacción en Cadena de la Polimerasa , Especies de Nitrógeno Reactivo/metabolismo , Especies Reactivas de Oxígeno/metabolismo
8.
J Pharmacol Sci ; 137(2): 154-161, 2018 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-29934052

RESUMEN

Mangiferin, a natural glucosyl xanthone, was confirmed to be an effective uric acid (UA)- lowering agent with dual action of inhibiting production and promoting excretion of UA. In this study, we aimed to evaluate the effect of mangiferin on alleviating hypertension induced by hyperuricemia. Mangiferin (30, 60, 120 mg/kg) was administered intragastrically to hyperuricemic rats induced by gavage with potassium oxonate (750 mg/kg). Systolic blood pressure (SBP), serum levels of UA, nitric oxide (NO), C-reactionprotein (CRP) and ONOO- were measured. The mRNA and protein levels of endothelial nitric oxide synthase (eNOS), intercellular adhesion molecule-1 (ICAM-1), CRP were also analyzed. Human umbilical vein endothelial cells (HUVECs) were used in vitro studies. Administration of mangiferin significantly decreased the serum urate level and SBP at 8 weeks and last to 12 weeks. Further more, mangiferin could increase the release of NO and decrease the level of CRP in blood. In addition, mangiferin reversed the protein expression of eNOS, CRP, ICAM-1 and ONOO- in aortic segments in hyperuricemic rats. The results in vitro were consistent with the observed results in vivo. Taken together, these data suggested that mangiferin has played an important part in alleviating hypertension induced by hyperuricemia via increasing NO secretion and improving endothelial function.


Asunto(s)
Hipertensión/tratamiento farmacológico , Hipertensión/etiología , Hiperuricemia/tratamiento farmacológico , Óxido Nítrico/metabolismo , Fitoterapia , Xantonas/administración & dosificación , Xantonas/farmacología , Administración Oral , Animales , Aorta/metabolismo , Proteína C-Reactiva/metabolismo , Células Endoteliales de la Vena Umbilical Humana , Humanos , Hipertensión/metabolismo , Hiperuricemia/inducido químicamente , Hiperuricemia/complicaciones , Hiperuricemia/metabolismo , Molécula 1 de Adhesión Intercelular/metabolismo , Mangifera/química , Óxido Nítrico Sintasa de Tipo III/metabolismo , Ácido Oxónico/efectos adversos , Hojas de la Planta/química , Ratas Sprague-Dawley , Sístole/efectos de los fármacos , Ácido Úrico/sangre , Xantonas/aislamiento & purificación
9.
Biol Pharm Bull ; 41(1): 99-105, 2018 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-29093325

RESUMEN

The mechanism of 3,5,2',4'-tetrahydroxychalcone on lowing urate level is still unknown. Here we investigated the effects of 3,5,2',4'-tetrahydroxychalcone on urate levels, xanthine oxidase/xanthine dehydrogenase (XOD/XDH) activities in hypoxanthine-induced hyperuricemic mice, as well as the effects of 3,5,2',4'-tetrahydroxychalcone on the mRNA expression levels and content of phosphoribosyl pyrophosphate synthetase (PRPS), phosphoribosyl pyrophosphate amidotransferase (PRPPAT) and hypoxanthine-guanine phosphoribosyl transferase (HGPRT). Our results demonstrated that 3,5,2',4'-tetrahydroxychalcone (1.0, 2.0, and 4.0 mg/kg) reduced the uric acid levels in serum of the hyperuricemic mice in dose- and time-dependent manners. The activities of XOD/XDH in serum and liver were also significantly inhibited by 3,5,2',4'-tetrahydroxychalcone; In addition, 3,5,2',4'-tetrahydroxychalcone decreased the mRNA expression of HGPRT in brain and content of PRPS and PRPPAT in liver. These findings demonstrated that 3,5,2',4'-tetrahydroxychalcone suppresses uric acid production by affecting the critical enzymes, XOD/XDH, PRPS, PRPPAT and HGPRT in purine nucleotide metabolism.


Asunto(s)
Chalconas/uso terapéutico , Hiperuricemia/tratamiento farmacológico , Ácido Úrico/sangre , Xantina Deshidrogenasa/metabolismo , Xantina Oxidasa/metabolismo , Animales , Modelos Animales de Enfermedad , Relación Dosis-Respuesta a Droga , Hiperuricemia/inducido químicamente , Hiperuricemia/metabolismo , Hipoxantina/farmacología , Hígado/efectos de los fármacos , Hígado/metabolismo , Masculino , Ratones Endogámicos , Purinas/metabolismo , Xantina Deshidrogenasa/genética , Xantina Oxidasa/genética
10.
Mol Microbiol ; 101(6): 1003-23, 2016 09.
Artículo en Inglés | MEDLINE | ID: mdl-27279039

RESUMEN

Borrelia burgdorferi maintains a complex life cycle between tick and vertebrate hosts. Although some genes have been identified as contributing to bacterial adaptation in the different hosts, the list is incomplete. In this manuscript, we report the first use of transposon mutagenesis combined with high-throughput sequencing (Tn-seq) in B. burgdorferi. We utilize the technique to investigate mechanisms of carbohydrate utilization in B. burgdorferi and the role of carbohydrate metabolism during mouse infection. We performed genetic fitness analyses to identify genes encoding factors contributing to growth on glucose, maltose, mannose, trehalose and N-acetyl-glucosamine. We obtained insight into the potential functions of proteins predicted to be involved in carbohydrate utilization and identified additional factors previously unrecognized as contributing to the metabolism of the tested carbohydrates. Strong phenotypes were observed for the putative carbohydrate phosphotransferase transporters BB0408 and BBB29 as well as the response regulator Rrp1. We further validated Tn-seq for use in mouse studies and were able to correctly identify known infectivity factors as well as additional transporters and genes on lp54 that may contribute to optimal mouse infection. As such, this study establishes Tn-seq as a powerful method for both in vitro and in vivo studies of B. burgdorferi.


Asunto(s)
Borrelia burgdorferi/metabolismo , Borrelia burgdorferi/patogenicidad , Enfermedad de Lyme/microbiología , Animales , Proteínas Bacterianas/metabolismo , Borrelia burgdorferi/genética , Metabolismo de los Hidratos de Carbono/genética , Elementos Transponibles de ADN , Regulación Bacteriana de la Expresión Génica , Aptitud Genética , Secuenciación de Nucleótidos de Alto Rendimiento/métodos , Proteínas de Transporte de Membrana/metabolismo , Ratones , Ratones Endogámicos C57BL , Mutagénesis Insercional , Fosfotransferasas/genética , Fosfotransferasas/metabolismo , Garrapatas/microbiología , Factores de Virulencia/metabolismo
11.
J Pharmacol Sci ; 135(3): 114-120, 2017 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-29132796

RESUMEN

Hyperuricemia, a long-term purine metabolic disorder, is a well-known risk factor for gout, hypertension and diabetes. In maintaining normal whole-body purine levels, xanthine oxidase (XOD) is a key enzyme in the purine metabolic pathway, as it catalyzes the oxidation of hypoxanthine to xanthine and finally to uric acid. Here we used the protein-ligand docking software idock to virtually screen potential XOD inhibitors from 3167 approved small compounds/drugs. The inhibitory activities of the ten compounds with the highest scores were tested on XOD in vitro. Interestingly, all the ten compounds inhibited the activity of XOD at certain degrees. Particularly, the anti-ulcerative-colitis drug olsalazine sodium demonstrated a great inhibitory activity for XOD (IC50 = 3.4 mg/L). Enzymatic kinetic studies revealed that the drug was a hybrid-type inhibitor of xanthine oxidase. Furthermore, the drug strikingly decreased serum urate levels, serum/hepatic activities of XOD at a dose-dependent manner in vivo. Thus, we demonstrated a successful hunting process of compounds/drugs for hyperuricemia through virtual screening, supporting a potential usage of olsalazine sodium in the treatment of hyperuricemia.


Asunto(s)
Ácidos Aminosalicílicos/farmacología , Antiulcerosos/farmacología , Ácido Úrico/sangre , Xantina Deshidrogenasa/antagonistas & inhibidores , Xantina Deshidrogenasa/metabolismo , Ácidos Aminosalicílicos/uso terapéutico , Animales , Relación Dosis-Respuesta a Droga , Evaluación Preclínica de Medicamentos , Hiperuricemia/tratamiento farmacológico , Técnicas In Vitro , Masculino , Ratones , Relación Estructura-Actividad
12.
Water Sci Technol ; 76(3-4): 555-566, 2017 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-28759438

RESUMEN

Coking coal, the raw material of a coke plant, was applied to the adsorption of coking wastewater. In this study, coking coal was directly treated with sulfuric acid to improve its surface properties and adsorption ability. Acid treatment was carried out at various concentrations, by varying from 0.001 to 1 mol/L. The samples were characterized by ash content analysis, scanning electron microscope (SEM), N2 adsorption-desorption analysis, Fourier transform infrared spectroscopy (FTIR), X-ray photoelectron spectroscopy (XPS), wettability analysis, and zeta potential analysis. These results demonstrated that H+ could react with inorganic minerals, which resulted in a significant variation of the chemical composition and the structure of coal surface. Furthermore, both the ash content and the surface content of O = C-O, C = O and C-O groups declined gradually as the concentration of sulfuric acid increased, while the surface area and pore volume of micropore, the lipophilic and hydrophobic properties, and zeta potential magnitude increased, resulting in enhanced hydrophobic and Van der Waals' forces between the fine coal and organic pollutants. Characterization modification showed a better performance in adsorption, the removal rate enhanced from 23% to 42% after treated by 1 mol/L sulfuric acid. It was concluded that the acid activation modified the lipophilic and hydrophobic properties, the surface charge properties, surface area and pore volume, the content of oxygen functional groups, all of which could be potentially useful in wastewater adsorption.


Asunto(s)
Carbón Mineral/análisis , Ácidos Sulfúricos/química , Eliminación de Residuos Líquidos/métodos , Aguas Residuales/química , Contaminantes Químicos del Agua/química , Adsorción , Espectroscopía de Fotoelectrones , Propiedades de Superficie
13.
Water Sci Technol ; 73(3): 582-7, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-26877041

RESUMEN

H2SO4 has an effect on the sorption of organic contaminants by coking coal (CC) in wastewater. This paper focused on the effect of pH on the removal of chemical oxygen demand (COD), phenols and ammonia. UV-vis spectra, Fourier transform infrared spectra, zeta potential and Brunauer, Emmett and Teller (BET) analysis were investigated to characterize the changes of CC properties and coking wastewater (CW) at different pH values. The results showed that the COD and phenol removal efficiencies increased with decreasing pH value, while the ammonia removal efficiency was decreased gradually. A new transmittance band in the region of 340-600 cm(-1) was observed in UV-vis spectra of CW in acidic condition. The absolute value of the zeta potential as the solution was gradually increasing with the increasing of pH value. Surface area and total pore volume of CC which was immersed in acidic solutions measured by BET were much higher than that of raw CC. CC has a greater adsorption capacity to organic pollution in the acidic solution mainly by van der Waals forces and hydrogen bonding.


Asunto(s)
Coque/análisis , Eliminación de Residuos Líquidos/métodos , Aguas Residuales/química , Contaminantes Químicos del Agua/química , Amoníaco/química , Análisis de la Demanda Biológica de Oxígeno , Concentración de Iones de Hidrógeno , Fenoles/química
14.
Water Sci Technol ; 74(3): 729-37, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-27508378

RESUMEN

pH-sensitive copolymers have been widely introduced to achieve rapid dewatering and consolidation of solids in mining and oil sands processing wastes. But no more attention has been given to the flocculation efficiency of solid suspensions as a function of pH using pH-sensitive copolymer. In this study, a pH-sensitive copolymer was synthesized and employed to investigate the flocculation behaviors of kaolin by focused beam reflectance measurement (FBRM). A titration test was introduced to characterize the copolymer conformation transition. The results demonstrated that at pH ranging from 3 to 6, with the pH increase, the zeta potential magnitude of kaolin particles increased, resulting in the repulsive forces between particles increasing. However, the hydrophobicity of kaolin increased as the pH increased. Thus, the hydrophobic forces could neutralize a part of the repulsive forces between particles and result in good and similar flocculation performances. At the pH greater than 6, the zeta potential magnitude of kaolin particles and copolymer molecules increased significantly, and the repulsive force between kaolin particles increased after copolymer addition due to the kaolin particles being more negatively charged, which resulted in poor flocculation efficiency and cloudy supernatant. It was concluded that the pH-sensitive copolymer could achieve both perfect flocculation efficiency and low moisture of filter cake at the isoelectric point of copolymer.


Asunto(s)
Caolín/química , Polímeros/química , Floculación , Concentración de Iones de Hidrógeno , Yacimiento de Petróleo y Gas
15.
Pharm Biol ; 54(9): 1680-6, 2016 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-26916555

RESUMEN

Context Mangiferin has been reported to possess a potential hypouricaemic effect. However, the pharmacokinetic studies in rats showed that its oral bioavailability was only 1.2%, suggesting that mangiferin metabolites might exert the action. Objective The hypouricaemic effect and the xanthine oxidase inhibition of mangiferin and norathyriol, a mangiferin metabolite, were investigated. Inhibition of norathyriol analogues (compounds 3-9) toward xanthine oxidase was also evaluated. Materials and methods For a dose-dependent study, mangiferin (1.5-6.0 mg/kg) and norathyriol (0.92-3.7 mg/kg) were administered intragastrically to mice twice daily for five times. For a time-course study, mice received mangiferin and norathyriol both at a single dose of 7.1 µmol/kg. In vitro, inhibition of test compounds (2.4-2.4 mM) against xanthine oxidase activity was evaluated by the spectrophotometrical method. The inhibition type was identified from Lineweaver-Burk plots. Results Norathyriol (0.92, 1.85 and 3.7 mg/kg) dose dependently decreased the serum urate levels by 27.0, 33.6 and 37.4%, respectively. The action was more potent than that of mangiferin at the low dose, but was equivalent at the higher doses. Additionally, the hypouricaemic action of them exhibited a time dependence. In vitro, norathyriol markedly inhibited the xanthine oxidase activities, with the IC50 value of 44.6 µM, but mangiferin did not. The kinetic studies showed that norathyriol was an uncompetitive inhibitor by Lineweaver-Burk plots. The structure-activity relationships exhibited that three hydroxyl groups in norathyriol at the C-1, C-3 and C-6 positions were essential for maintaining xanthine oxidase inhibition. Discussion and conclusion Norathyriol was responsible for the hypouricaemic effect of mangiferin via inhibiting xanthine oxidase activity.


Asunto(s)
Inhibidores Enzimáticos/farmacología , Supresores de la Gota/farmacología , Hiperuricemia/tratamiento farmacológico , Ácido Úrico/sangre , Xantenos/farmacología , Xantina Oxidasa/antagonistas & inhibidores , Xantonas/farmacología , Administración Oral , Animales , Biomarcadores/sangre , Biotransformación , Modelos Animales de Enfermedad , Relación Dosis-Respuesta a Droga , Esquema de Medicación , Inhibidores Enzimáticos/administración & dosificación , Inhibidores Enzimáticos/metabolismo , Supresores de la Gota/administración & dosificación , Supresores de la Gota/metabolismo , Hiperuricemia/sangre , Hiperuricemia/inducido químicamente , Hiperuricemia/enzimología , Cinética , Ratones , Estructura Molecular , Ácido Oxónico , Relación Estructura-Actividad , Xantenos/administración & dosificación , Xantenos/metabolismo , Xantina Oxidasa/metabolismo , Xantonas/administración & dosificación , Xantonas/metabolismo
16.
Infect Immun ; 84(3): 754-64, 2015 Dec 28.
Artículo en Inglés | MEDLINE | ID: mdl-26712207

RESUMEN

The phosphoenolpyruvate phosphotransferase system (PEP-PTS) and adenylate cyclase (AC) IV (encoded by BB0723 [cyaB]) are well conserved in different species of Borrelia. However, the functional roles of PEP-PTS and AC in the infectious cycle of Borrelia have not been characterized previously. We examined 12 PEP-PTS transporter component mutants by needle inoculation of mice to assess their ability to cause mouse infection. Transposon mutants with mutations in the EIIBC components (ptsG) (BB0645, thought to be involved in glucose-specific transport) were unable to cause infection in mice, while all other tested PEP-PTS mutants retained infectivity. Infectivity was partially restored in an in trans-complemented strain of the ptsG mutant. While the ptsG mutant survived normally in unfed as well as fed ticks, it was unable to cause infection in mice by tick transmission, suggesting that the function of ptsG is essential to establish infection by either needle inoculation or tick transmission. In Gram-negative organisms, the regulatory effects of the PEP-PTS are mediated by adenylate cyclase and cyclic AMP (cAMP) levels. A recombinant protein encoded by B. burgdorferi BB0723 (a putative cyaB homolog) was shown to have adenylate cyclase activity in vitro; however, mutants with mutations in this gene were fully infectious in the tick-mouse infection cycle, indicating that its function is not required in this process. By transcriptome analysis, we demonstrated that the ptsG gene may directly or indirectly modulate gene expression of Borrelia burgdorferi. Overall, the PEP-PTS glucose transporter PtsG appears to play important roles in the pathogenesis of B. burgdorferi that extend beyond its transport functions.


Asunto(s)
Proteínas Bacterianas/metabolismo , Borrelia burgdorferi/enzimología , Borrelia burgdorferi/patogenicidad , Regulación Bacteriana de la Expresión Génica , Sistema de Fosfotransferasa de Azúcar del Fosfoenolpiruvato/metabolismo , Animales , Proteínas Bacterianas/genética , Borrelia burgdorferi/genética , Femenino , Humanos , Ratones , Ratones Endogámicos C3H , Sistema de Fosfotransferasa de Azúcar del Fosfoenolpiruvato/genética , Transcripción Genética , Virulencia
17.
Biol Pharm Bull ; 38(10): 1591-8, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-26228630

RESUMEN

Mangiferin, a natural glucosyl xanthone from the leaves of Mangifera indica L., was previously shown to exert potent hypouricemic effects associated with inhibition of the activity of xanthine dehydrogenase/oxidase. The present study aimed to evaluate its uricosuric effect and possible molecular mechanisms underlying the renal urate transporters responsible for urate reabsorption in vivo. Mangiferin (1.5-24.0 mg/kg) was administered intragastrically to hyperuricemic mice and rats induced by the intraperitoneal injection of uric acid and potassium oxonate, respectively. The uricosuric effect was evaluated by determining the serum and urinary urate levels as well as fractional excretion of uric acid (FEUA). The mRNA and protein levels of renal urate-anion transporter 1 (URAT1), organic anion transporter 10 (OAT10), glucose transporter 9 (GLUT9), and PDZ domain-containing protein (PDZK1) were analyzed. The administration of mangiferin significantly decreased the serum urate levels in hyperuricemic mice in a dose- and time-dependent manner. In hyperuricemic rats, mangiferin also reduced the serum urate levels and increased the urinary urate levels and FEUA. These results indicate that mangiferin has uricosuric effects. Further examination showed that mangiferin markedly inhibited the mRNA and protein expression of renal URAT1, OAT10, and GLUT9 in hyperuricemic rats, but did not interfere with PDZK1 expression. Taken together, these findings suggest that mangiferin promotes urate excretion by the kidney, which may be related to the inhibition of urate reabsorption via downregulation of renal urate transporters.


Asunto(s)
Hiperuricemia/metabolismo , Riñón/efectos de los fármacos , Ácido Úrico/metabolismo , Uricosúricos/farmacología , Xantonas/farmacología , Animales , Proteínas de Transporte de Anión/genética , Proteínas de Transporte de Anión/metabolismo , Proteínas Portadoras/genética , Proteínas Portadoras/metabolismo , Proteínas del Citoesqueleto , Hiperuricemia/sangre , Hiperuricemia/inducido químicamente , Riñón/metabolismo , Masculino , Ratones , Proteínas de Transporte de Monosacáridos/genética , Proteínas de Transporte de Monosacáridos/metabolismo , Ácido Oxónico , Ratas Sprague-Dawley , Ácido Úrico/sangre , Ácido Úrico/orina
18.
Arch Environ Contam Toxicol ; 69(2): 133-42, 2015 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-25838210

RESUMEN

In this study, ice and water samples were collected from seven sites along the Baotou section of the Yellow River during winter 2013. Total polycyclic aromatic hydrocarbon (PAH) concentrations in the ice and in the water under the ice ranged from 21.3 to 59.4 ng L(-1), and from 38.3 to 222.4 ng L(-1), respectively. The average concentration in water under the ice was approximately 2.5 times greater than the average concentration in the ice phase. Four-ring PAHs dominated and accounted for 68.2 and 76.0 % of the total PAHs in ice and water, respectively. PAH concentrations were highest at sampling site S2 and were also relatively high at sites S4 and S5. PAH sources in ice and in water under the ice were similar. Three components were selected to represent the coal-combustion sources of PAHs. Because it was the main pollutant, and its concentrations were the highest, we examined the photodegradation behavior of fluoranthene and investigated the effects of light-sensitive materials (H2O2, acetone, and sediment) on fluoranthene photodegradation in the ice phase. Results showed that low H2O2 concentrations promoted photoconversion in the initial stage of the reaction and that degradation rates decreased later in the reaction. Likewise, high H2O2 concentrations promoted photoconversion. As acetone concentrations increased, the rates of fluoranthene-degradation decreased. Sediments may also have decreased the degradation rate of fluoranthene.


Asunto(s)
Monitoreo del Ambiente , Hidrocarburos Policíclicos Aromáticos/análisis , Ríos/química , Contaminantes Químicos del Agua/análisis , China , Estaciones del Año
19.
Water Sci Technol ; 72(1): 158-63, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-26114284

RESUMEN

Coke plant wastewater (CPW) is an intractable chemical wastewater, and it contains many toxic pollutants. This article presents the results of research on a semi-industrial adsorption method of coking wastewater treatment. As a sorbent, the coking coal (CC) was a dozen times less expensive than active carbon. The treatment was conducted within two scenarios, as follows: (1) adsorption after biological treatment of CPW with CC at 40 g L(-1); the chemical oxygen demand (COD) removal was 75.66%, and the concentration was reduced from 178.99 to 43.56 mg L(-1); (2) given an adsorption by CC of 250 g L(-1) prior to the biological treatment of CPW, the eliminations of COD and phenol were 58.08% and 67.12%, respectively. The CC that adsorbed organic pollution and was returned to the coking system might have no effect on both coke oven gas and coke.


Asunto(s)
Carbón Mineral/análisis , Residuos Industriales/análisis , Compuestos Orgánicos/química , Eliminación de Residuos Líquidos/métodos , Aguas Residuales/química , Adsorción , Análisis de la Demanda Biológica de Oxígeno , Coque/análisis , Fenol/química , Eliminación de Residuos Líquidos/instrumentación
20.
Lipids Health Dis ; 13: 98, 2014 Jun 21.
Artículo en Inglés | MEDLINE | ID: mdl-24950764

RESUMEN

BACKGROUND: 3-Hydroxy-3-methyl-glutaryl CoA (HMG-CoA) reductase inhibitors or statins are competitive inhibitors of the rate-limiting enzyme in cholesterol biosynthesis. Currently, statins are used as first-line therapy in the treatment of diabetic dyslipidemia. However, effects of statins on ß cell function remains unclear. This study aims to examine effects of atorvastatin treatment on pancreatic ß cell function in obese C57BL/6 J mice and the possible mechanisms. METHODS: Diet-induced obesity (DIO) C57BL/6 J mice were treated with atorvastatin (30 mg/kg/day) for 58 days. ß cell function was assessed by hyperglycemic clamp and the area of insulin-positive ß cells was examined by immunofluorescence. Gene expression was assessed by RT-PCR, and endoplasmic reticulum (ER) stress related proteins were examined by Western blot. Additionally, cell viability and apoptosis of the cholesterol-loaded NIT-1 cells were investigated after atorvastatin treatment. RESULTS: Hyperglycemic clamp study revealed that glucose infusion rate (GIR) and insulin stimulation ratio in atorvastatin-treated DIO mice were markedly higher than control mice (P < 0.05, P < 0.01 vs. con), indicating preserved ß-cell sensitivity to glucose. Lipid profiles of plasma triglyceride (TG), pancreas TG and plasma cholesterol (CHO) were improved. Pancreas weight and weight index were improved significantly after atorvastatin treatment (P < 0.05 vs. con). Immunofluorescence results showed that atorvastatin-treated mice had significantly larger insulin-positive ß cell area (P < 0.05 vs. con). Furthermore, RT-PCR and western blot showed that the mRNA and protein expression of pancreatic and duodenal homeobox 1 (Pdx1) in the pancreas were upregulated (P < 0.001, P < 0.01 vs. con). Moreover, the expression level of ER stress markers of activating transcription factor 4 (ATF4), CCAAT-enhancer-binding protein homologous protein (CHOP) and phosphorylated eukaryotic initiation factor 2α (eIF2α) were downregulated in the pancreas of atorvastatin-treated mice (P < 0.001, P < 0.01, P < 0.01 vs. con). Besides, atorvastatin protected the pancreatic ß cell line of NIT-1 from cholesterol-induced apoptosis. Western blot showed increased expression of anti-apoptotic protein of B-cell lymphoma 2 (Bcl-2). CONCLUSION: Pancreatic ß cell function of obese C57BL/6 J mice was preserved after atorvastatin treatment, and this improvement may be attributed to enhanced pancreas proliferation and amelioration of pancreatic ER stress.


Asunto(s)
Estrés del Retículo Endoplásmico/efectos de los fármacos , Ácidos Heptanoicos/uso terapéutico , Páncreas/efectos de los fármacos , Páncreas/metabolismo , Pirroles/uso terapéutico , Animales , Apoptosis/efectos de los fármacos , Atorvastatina , Western Blotting , Supervivencia Celular/efectos de los fármacos , Técnica del Anticuerpo Fluorescente , Células Secretoras de Insulina/efectos de los fármacos , Células Secretoras de Insulina/metabolismo , Masculino , Ratones , Ratones Endogámicos C57BL , Obesidad/tratamiento farmacológico , Obesidad/metabolismo , Reacción en Cadena en Tiempo Real de la Polimerasa
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