RESUMEN
Triterpenoid saponin derivatives oleanolic acid (OA) and ursolic acid (UA), but not betulinic acid (BA), were previously found to have strong antimicrobial activity against Streptococcus mutans. OA and UA inhibited the transcription of genes related to peptidoglycan biosynthesis, thereby preventing bacterial growth. However, it is not clear whether this is the only pathway involved in the antimicrobial activity of these compounds against S. mutans. Therefore, we used quantitative real-time PCR (qPCR) and microarray analyses to examine the expression of genes related to essential metabolic pathways in S. mutans UA159 following incubation with OA, UA, or BA. An oligonucleotide array consisting of 5363 probes was designed to survey 1928 of the 1963 genes in the genome of S. mutans UA159. Genes that showed >2-fold changes in expression in response to the treatment conditions were annotated, and selected target genes involved in central metabolism were analyzed by qPCR. Microarray analysis confirmed that the gene expression patterns of the OA- and UA-treated cells differed from that of the BA-treated culture, indicating differences in the antimicrobial mechanism. In particular, the expression of pfk and pykF, coding for glycolysis regulatory proteins phosphofructokinase and pyruvate kinase, respectively, were significantly decreased in the OA and UA groups (P < 0.05), as were genes involved in fatty acid and amino acid synthesis. In addition, the microarray analysis confirmed previous qPCR results showing that peptidoglycan synthesis is down-regulated in the OA- and UA-treated groups. OA and UA also appear to decrease the generation of organic acids by S. mutans UA159, which would have an anticaries effect. Overall, these findings suggest that OA and UA affect multiple genes involved in the central metabolism of S. mutans, with inhibition of glycolysis, fatty acid synthesis, amino acid synthesis, and peptidoglycan synthesis, all contributing to their antimicrobial activity.
Asunto(s)
Antibacterianos/farmacología , Ácido Oleanólico/farmacología , Streptococcus mutans/efectos de los fármacos , Triterpenos/farmacología , Proteínas Bacterianas/genética , Proteínas Bacterianas/metabolismo , Regulación Bacteriana de la Expresión Génica/efectos de los fármacos , Triterpenos Pentacíclicos , Streptococcus mutans/genética , Streptococcus mutans/metabolismo , Ácido Betulínico , Ácido UrsólicoRESUMEN
The objective of the study was to investigate the antimicrobial effects of purified single compounds from ethanol-extracted licorice root on Streptococcus mutans. The crude licorice root extract (CLE) was obtained from Glycyrrhiza uralensis, which was subjected to column chromatography to separate compounds. Purified compounds were identified by mass spectrometry and nuclear magnetic resonance. Antimicrobial activities of purified compounds from CLE were evaluated by determining the minimum inhibitory concentration and by performing time-kill kinetics. The inhibitory effects of the compounds on biofilm development were evaluated using crystal violet assay and confocal microscopy. Cell toxicity of substances to normal human gingival fibroblast (NHGF) cells was tested using a methyl thiazolyl tetrazolium assay. Chlorhexidine digluconate (CHX) was used in the control group. Three antimicrobial flavonoids, 1-methoxyficifolinol, licorisoflavan A, and 6,8-diprenylgenistein, were isolated from the CLE. We found that the three flavonoids and CHX had bactericidal effects on S. mutans UA159 at the concentration of ≥4 and ≥1 µg/ml, respectively. The purified compounds completely inhibited biofilm development of S. mutans UA159 at concentrations over 4 µg/ml, which was equivalent to 2 µg/ml of CHX. Confocal analysis showed that biofilms were sparsely scattered in the presence of over 4 µg/ml of the purified compounds. However, the three compounds purified from CLE showed less cytotoxic effects on NHGF cells than CHX at these biofilm-inhibitory concentrations. Our results suggest that purified flavonoids from CLE can be useful in developing oral hygiene products, such as gargling solutions and dentifrices for preventing dental caries.
Asunto(s)
Antiinfecciosos/farmacología , Benzofuranos/farmacología , Benzopiranos/farmacología , Genisteína/análogos & derivados , Glycyrrhiza uralensis , Extractos Vegetales/farmacología , Streptococcus mutans/efectos de los fármacos , Antiinfecciosos/administración & dosificación , Antiinfecciosos Locales/farmacología , Benzopiranos/administración & dosificación , Biopelículas/efectos de los fármacos , Clorhexidina/análogos & derivados , Clorhexidina/farmacología , Fibroblastos/efectos de los fármacos , Flavonoides/administración & dosificación , Flavonoides/farmacología , Genisteína/administración & dosificación , Genisteína/farmacología , Violeta de Genciana , Encía/citología , Encía/efectos de los fármacos , Humanos , Espectroscopía de Resonancia Magnética , Pruebas de Sensibilidad Microbiana , Microscopía Confocal , Extractos Vegetales/administración & dosificación , Raíces de Plantas , Streptococcus sobrinus/efectos de los fármacos , Sales de Tetrazolio , TiazolesRESUMEN
The nature and importance of the DNA repair system in the chloroplasts of higher plants under oxidative stress or UV radiation-induced genotoxicity was investigated via gain-of-functional approaches exploiting bacterial RecAs. For this purpose, transgenic tobacco (Nicotiana tabacum) plants and cell suspensions overexpressing Escherichia coli or Pseudomonas aeruginosa RecA fused to a chloroplast-targeting transit peptide were first produced. The transgenic tobacco plants maintained higher amounts of chloroplast DNA compared with wild-type (WT) upon treatments with methyl viologen (MV), a herbicide that generates reactive oxygen species (ROS) in chloroplasts. Consistent with these results, the transgenic tobacco leaves showed less bleaching than WT following MV exposure. Similarly, the MV-treated transgenic Arabidopsis plants overexpressing the chloroplast RecA homologue RECA1 showed weak bleaching, while the recA1 mutant showed opposite results upon MV treatment. In addition, when exposed to UV-C radiation, the dark-grown E. coli RecA-overexpressing transgenic tobacco cell suspensions, but not their WT counterparts, resumed growth and greening after the recovery period under light conditions. Measurements of UV radiation-induced chloroplast DNA damage using DraI assays (Harlow et al. 1994) with the chloroplast rbcL DNA probe and quantitative PCR analyses showed that the transgenic cell suspensions better repaired their UV-C radiation-induced chloroplast DNA lesions compared with WT. Taken all together, it was concluded that RecA-overexpressing transgenic plants are endowed with an increased chloroplast DNA maintenance capacity and enhanced repair activities, and consequently have a higher survival tolerance to genotoxic stresses. These observations are made possible by the functional compatibility of the bacterial RecAs in chloroplasts.
Asunto(s)
Daño del ADN , ADN de Cloroplastos/genética , Nicotiana/genética , Paraquat/farmacología , Rec A Recombinasas/metabolismo , Rayos Ultravioleta , Secuencia de Aminoácidos , Proteínas Bacterianas/genética , Proteínas Bacterianas/metabolismo , Reparación del ADN , ADN de Cloroplastos/efectos de los fármacos , ADN de Cloroplastos/efectos de la radiación , Datos de Secuencia Molecular , Plantas Modificadas Genéticamente/efectos de los fármacos , Plantas Modificadas Genéticamente/genética , Plantas Modificadas Genéticamente/efectos de la radiación , Rec A Recombinasas/genética , Alineación de Secuencia , Nicotiana/efectos de los fármacos , Nicotiana/efectos de la radiaciónRESUMEN
On the basis of the DNA-DNA hybridization patterns and phenotypic characteristics, Fusobacterium nucleatum was classified into five subspecies. Previous studies have suggested that F. nucleatum subsp. vincentii is genetically similar to F. nucleatum subsp. fusiforme. The aim of this study was to investigate the possibility of classifying these two subspecies into a single subspecies by phylogenetic analysis using a single sequence (24,715 bp) concatenated 22 housekeeping genes of eight F. nucleatum strains including type strains of five F. nucleatum subspecies. The phylogenetic analysis indicated that F. nucleatum subsp. vincentii and F. nucleatum subsp. fusiforme were clustered in the same group and each strain of other F. nucleatum subspecies were also separated into the same cluster. These results suggested that F. nucleatum subsp. fusiforme and F. nucleatum subsp. vincentii can be classified into a single subspecies. F. nucleatum subsp. vincentii was early published name; therefore, F. nucleatum subsp. fusiforme Gharbia and Shah 1992 can be regarded as a later synonym of F. nucleatum subsp. vincentii Dzink et al. 1990.
Asunto(s)
Fusobacterium nucleatum/clasificación , Proteínas Bacterianas/genética , Análisis por Conglomerados , ADN Bacteriano/química , ADN Bacteriano/genética , Fusobacterium nucleatum/genética , Filogenia , Análisis de Secuencia de ADN , Homología de Secuencia de Ácido NucleicoRESUMEN
Fusobacterium nucleatum is classified into five subspecies. F. nucleatum ChDC F128 was isolated from a periodontitis lesion and proposed as a new subspecies based on the comparison of the nucleotide sequences of the RNA polymerase beta subunit and zinc protease genes. Here, we report the draft genome sequence of the strain.
Asunto(s)
Infecciones por Fusobacterium/microbiología , Fusobacterium nucleatum/genética , Genoma Bacteriano , Periodontitis/microbiología , Fusobacterium nucleatum/clasificación , Humanos , Datos de Secuencia MolecularRESUMEN
Fusobacterium nucleatum, one of the major causative bacteria of periodontitis, is classified into five subspecies (nucleatum, polymorphum, vincentii, animalis, and fusiforme) on the basis of the several phenotypic characteristics and DNA homology. This is the first report of the draft genome sequence of F. nucleatum subsp. fusiforme ATCC 51190(T).
Asunto(s)
Fusobacterium nucleatum/clasificación , Fusobacterium nucleatum/genética , Genoma Bacteriano , Datos de Secuencia MolecularRESUMEN
Adipocyte differentiation has been a target in anti-obesity strategies and is known to be closely related to lipid metabolism. Ceramide, a major sphingolipid metabolite, has been implicated in differentiation. In this study, we investigated whether ceramide biosynthesis is related to adipogenesis in 3T3-L1 cells. Preadipocytes can be differentiated synchronously by a mixture of adipogenic inducers including 3-isobutyl-1-methylxanthine, dexamethasone and insulin. The number of lipid droplets and the triglyceride content, which are differentiation biomarkers, gradually increased during adipogenesis. Interestingly, ceramide and sphingosine contents in the differentiated cells were decreased compared to those in preadipocytes. When the preadipocytes were treated with an 3-isobutyl-1-methylxanthine- or dexamethasone- or insulin-deficient mixture of inducers, the cellular ceramide levels were significantly increased compared with those in cells treated with the complete set of inducers. When preadipocytes were treated with 0, 0.1 or 1 µg/ml insulin along with 3-isobutyl-1-methylxanthine and dexamethasone, the ceramide levels were decreased and the triglyceride content was increased in a concentration-dependent manner. When the cells were treated with epigallocatechin gallate, an adipocyte differentiation inhibitor, during adipogenesis, the ceramide levels of adipocytes were increased and the fat content was decreased. In conclusion, our findings demonstrate that cellular ceramide levels are inversely correlated with adipocyte differentiation.
Asunto(s)
Adipocitos/metabolismo , Adipogénesis , Ceramidas/metabolismo , Células 3T3-L1 , Adipocitos/citología , Adipocitos/efectos de los fármacos , Adipogénesis/efectos de los fármacos , Animales , Catequina/análogos & derivados , Catequina/farmacología , Metabolismo de los Lípidos/efectos de los fármacos , Ratones , Terapia Molecular Dirigida , Obesidad/tratamiento farmacológico , Esfingosina/metabolismo , Triglicéridos/metabolismoRESUMEN
PURPOSE: Minimally invasive treatments for early breast cancer have been reported. The objective of this study was to evaluate and compare two such treatments, laser ablation and photodynamic therapy (PDT), regarding their therapeutic efficacy for breast cancer. METHODS: Breast tumors were induced in 12 mice models. The treatment options were classified into four groups: control group (without any treatment, A), group treated only with laser ablation (B), group treated only with PDT (C), and group treated with the combination of laser ablation followed by PDT (D). The treatment effects were compared among these groups. RESULTS: Among the groups, the group D underwent the most effective treatment for breast cancer. Not only were the breast cancer cells necrotized by laser ablation, but the tumor margin was also managed by PDT. CONCLUSIONS: The treatment method combining laser ablation and PDT showed superior results to single treatment techniques using just one of these approaches.
Asunto(s)
Neoplasias de la Mama/patología , Neoplasias de la Mama/cirugía , Terapia por Láser/métodos , Fotoquimioterapia/métodos , Animales , Biopsia con Aguja , Terapia Combinada , Modelos Animales de Enfermedad , Femenino , Inmunohistoquímica , Ratones , Ratones Endogámicos BALB C , Fármacos Fotosensibilizantes/farmacología , Proyectos Piloto , Distribución Aleatoria , Resultado del Tratamiento , Ensayos Antitumor por Modelo de XenoinjertoRESUMEN
Cyclic AMP-cAMP receptor protein (CRP) complex plays an essential role in the global regulation of Vibrio vulnificus virulence. We found that growth retardation of V. vulnificus caused by mutation of the crp gene encoding CRP was exacerbated under iron-limited conditions. Accordingly, we investigated the effect of crp mutation on the expression of the vulnibactin-mediated iron-uptake system and the ability of V. vulnificus to utilize transferrin-bound iron, and thus to grow in cirrhotic ascites, a human ex vivo system. The production of vulnibactin was suppressed, and the transcription of the vis and vuuA genes, which encode an enzyme required for vulnibactin synthesis and vulnibactin receptor protein, was also suppressed in the crp mutant. Moreover, the crp mutant could not utilize transferrin-bound iron, and its growth was severely suppressed both on transferrin-bound iron and in cirrhotic ascites. All the defects in the crp mutant were recovered by the in trans complementation of the wild-type crp gene. Putative CRP-binding sequences were found in the regulatory regions of the fur, vis and vuuA genes. These results indicate that crp mutation attenuates the ability to grow on transferrin-bound iron and in a human body fluid by down-regulating the vulnibactin-mediated iron-uptake system.
Asunto(s)
Proteínas de la Membrana Bacteriana Externa/fisiología , Hierro/metabolismo , Transferrina/metabolismo , Vibrio vulnificus/metabolismo , Amidas/metabolismo , Líquido Ascítico , Proteínas de la Membrana Bacteriana Externa/genética , Proteínas Bacterianas/genética , Proteínas Bacterianas/metabolismo , Secuencia de Bases , Medios de Cultivo , Regulación hacia Abajo , Humanos , Datos de Secuencia Molecular , Mutación , Oxazoles/metabolismo , Receptores de AMP Cíclico/metabolismo , Proteínas Represoras/genética , Proteínas Represoras/metabolismo , Sideróforos/metabolismo , Vibrio vulnificus/crecimiento & desarrolloRESUMEN
To elucidate the mechanisms underlying the in vivo suppression and inactivation of Vibrio vulnificus hemolysin (VvhA), we used cirrhotic ascites fluid as a human ex vivo experimental system. VvhA expression was suppressed in proportion to the amount of cirrhotic ascites. The expression of vvhA in undiluted cirrhotic ascites could be suppressed further by the addition of glucose, a constituent of cirrhotic ascites. VvhA was readily inactivated in the presence of cirrhotic ascites by a cholesterol-mediated oligomerization and interaction with an undefined constituent(s) of cirrhotic ascites. These results indicate that the expression of vvhA can be suppressed and that any VvhA produced is inactivated by the constituents of cirrhotic ascites. Our results suggest that only a very small portion of the VvhA that is produced in human body fluids may actually contribute to the pathogenesis of V. vulnificus septicemia. It is suggested that cirrhotic ascites could be used as a human ex vivo experimental system for the studies on the in vivo expression and the significance of V. vulnificus virulence factors.
Asunto(s)
Proteínas Bacterianas/antagonistas & inhibidores , Proteínas Bacterianas/biosíntesis , Cirrosis Hepática/inmunología , Cirrosis Hepática/microbiología , Vibrio vulnificus/metabolismo , Ascitis/inmunología , Ascitis/microbiología , Proteínas Bacterianas/genética , Colesterol/farmacología , Glucosa/farmacología , Proteínas Hemolisinas , Humanos , Cirrosis Hepática/metabolismo , Cirrosis Hepática/patología , Vibrio vulnificus/genéticaRESUMEN
Swarming has proven to be a good in vitro model for bacterial surface adherence and colonization, and the swarming differentiation of a bacterium has been shown to be coupled with changes in the expression of virulence factors associated with its invasiveness, particularly in the early stages of infection. In this study, we attempted to determine whether the expression of vvhA, which encodes for hemolysin/cytolysin (VvhA), is either upregulated or downregulated during the swarming differentiation of V. vulnificus. The insertional inactivation of vvhA itself exerted no detectable effect on the expression of V. vulnificus swarming motility. However, in our lacZ-fused vvhA transcriptional reporter assay, vvhA expression decreased in swarming V. vulnificus as compared to non-swarming or planktonic V. vulnificus. The reduced expression of vvhA in swarming V. vulnificus increased as a result of the deletional inactivation of luxS, a gene associated with quorum sensing. These results show that vvhA expression in swarming V. vulnificus is downregulated via the activity of the LuxS quorum-sensing system, suggesting that VvhA performs no essential role in the invasiveness of V. vulnificus via the adherence to and colonization on the body surfaces required in the early stages of the infection. However, VvhA may play a significant role in the pathophysiological deterioration occurring after swarming V. vulnificus is differentiated into planktonic V. vulnificus.
Asunto(s)
Proteínas Bacterianas/fisiología , Movimiento Celular/genética , Regulación Bacteriana de la Expresión Génica , Vibrio vulnificus/patogenicidad , Adhesión Bacteriana/genética , Proteínas Bacterianas/genética , Liasas de Carbono-Azufre , Diferenciación Celular , Regulación hacia Abajo , Genes Reporteros/genética , Mutación , Regulación hacia Arriba , Vibrio vulnificus/citología , Vibrio vulnificus/genéticaRESUMEN
This study was designed to determine whether or not Vibrio vulnificus metalloprotease VvpE can promote iron uptake via the proteolytic cleavage of human hemoglobin. We found that V. vulnificus utilized hemoglobin as an iron source more efficiently via the vulnibactin-mediated iron-uptake system than via the HupA-mediated iron-uptake system and, of the proteases produced by V. vulnificus, VvpE was found to be the only protease capable of destroying hemoglobin. However, VvpE expression, on both the transcriptional and protein levels, was suppressed in iron-limited media. However, vvpE transcription, but not extracellular VvpE production, was reactivated by the addition of hemoglobin or inorganic iron into iron-limited media. Moreover, vvpE transcription began only in the late growth phase when V. vulnificus had already consumed most of the iron for growth. In addition, neither vvpE mutation nor in trans vvpE complementation affected the ability of V. vulnificus to acquire iron or to grow in iron-limited media or in cirrhotic ascites containing hemoglobin. Hemoglobin added into iron-limited media was not destroyed, but gradually formed an insoluble aggregate during culture; this aggregation of hemoglobin occurred regardless of vvpE mutation or complementation. These results indicate that VvpE is not required for efficient iron uptake from hemoglobin. On the contrary, hemoglobin or iron is required for efficient vvpE transcription. In addition, a discrepancy exists between vvpE transcription and extracellular VvpE production in iron-limited media containing inorganic iron or hemoglobin, which suggests that additional unknown posttranscriptional events may be involved in the extracellular production of VvpE.
Asunto(s)
Hemoglobinas/metabolismo , Hierro/metabolismo , Metaloproteasas/metabolismo , Vibrio vulnificus/enzimología , Proteínas Bacterianas/genética , Proteínas Bacterianas/metabolismo , Electroforesis en Gel de Poliacrilamida/métodos , Regulación Bacteriana de la Expresión Génica/genética , Humanos , Hierro/farmacocinética , Metaloproteasas/genética , Mutación/genética , Reacción en Cadena de la Polimerasa/métodos , Transcripción Genética/genética , Transcripción Genética/fisiología , Vibrio vulnificus/genética , Vibrio vulnificus/metabolismoRESUMEN
BACKGROUND: Some studies have shown that Sasang typology is related to specific problem behaviors, but research on the associations between Sasang types and problem behaviors in children is scarce. The purpose of this study was to examine the associations between Sasang types and problem behaviors in Korean high school students. METHODS: A total of 686 Korean high school students (371 boys and 315 girls) completed the Korean version of Youth Self-Report (YSR) for describing the problem behaviors in adolescents and the Sasang Personality Questionnaire (SPQ) for measuring the temperament characteristics of Sasang typology. The correlation between YSR and SPQ subscales was investigated, and the differences of YSR among the high (30%), middle (40%), and low (30%) SPQ total score groups were examined with Analysis of variance. The profile analysis was also performed to compare YSR subscale profiles of three SPQ total score groups. RESULTS: The SPQ total score significantly (p < 0.001) correlated positively with YSR externalizing problems (r = 0.293 and r = 0.248) and negatively with YSR internalizing problems (r = -0.211 and r = -0.150) in males and females, respectively. The YSR externalizing problem score is significantly higher in the high SPQ total score group (13.14 ± 9.33 and 10.03 ± 5.34 for males and females, respectively) than in the low SPQ total score group (8.18 ± 5.53 and 8.58 ± 5.73, respectively), and the YSR internalizing problem score is significantly higher in the low SPQ total score group (11.28 ± 8.92 and 12.97 ± 8.69 for males and females, respectively) than in the high SPQ total score group (9.35 ± 9.00 and 11.28 ± 7.58, respectively). The YSR profiles for three SPQ total score groups were significantly different for males (profile analysis, df = 12.324, F = 18.164, p < 0.001) and females (df = 12.677, F = 11.601, p < 0.001). CONCLUSION: These results could be recognized as the SPQ, and Sasang typology would be useful for predicting the pathological patterns even of psychological problems in high school students. This study would be useful for the screening of psychopathological problems and character development in adolescents.
RESUMEN
In this study, we attempted to determine the effects of iron-availability and the activity of the bacterial iron-uptake system (IUS) on the growth of Staphylococcus aureus in human peritoneal dialysate (HPD) solution. A streptonigrin-resistant S. aureus (SRSA) strain, isolated from S. aureus ATCC 6538, exhibited defective siderophore production, thereby resulting in ineffective uptake of iron from low iron-saturated transferrin. The growth of both strains was stimulated in HPD solution supplemented with FeCl3 and holotransferrin, but growth was inhibited in HPD solution which had been supplemented with apotransferrin and dipyridyl. The SRSA strain grew less robustly than did its parental strain in both iron-supplemented HPD solution and regular HPD solution. These results indicate that iron-availability and siderophore-mediated IUS activity in particular, the ability to produce siderophores and thus capture iron from low iron-saturated transferrin play critical roles in the growth of S. aureus in HPD solution. Our results also indicated that the possibility of using iron chelators as therapeutic or preventive agents warrants further evaluation.
Asunto(s)
Soluciones para Diálisis , Diálisis Peritoneal Ambulatoria Continua/efectos adversos , Sideróforos/biosíntesis , Staphylococcus aureus/crecimiento & desarrollo , Staphylococcus aureus/metabolismo , Infección Hospitalaria/etiología , Infección Hospitalaria/prevención & control , Farmacorresistencia Bacteriana , Humanos , Técnicas In Vitro , Hierro/metabolismo , Quelantes del Hierro/farmacología , Infecciones Estafilocócicas/etiología , Infecciones Estafilocócicas/prevención & control , Staphylococcus aureus/efectos de los fármacos , Staphylococcus aureus/aislamiento & purificación , Estreptonigrina/farmacología , Transferrina/metabolismoRESUMEN
Staphylococcus aureus is known to be capable of utilizing transferrin-bound iron, via both siderophore- and transferrin-binding protein (named IsdA)-mediated iron-acquisition systems. This study was designed in order to determine which iron-acquisition system plays the essential or dominant role with respect to the acquisition of iron from human transferrin, in the growth of S. aureus. Holotransferrin (HT) and partially iron-saturated transferrin (PT), but not apotransferrin (AT), were found to stimulate the growth of S. aureus. S. aureus consumed most of the transferrin-bound iron during the exponential growth phase. Extracellular proteases were not, however, involved in the liberation of iron from transferrin. Transferrin-binding to the washed whole cells via IsdA was not observed during the culture. The expression of IsdA was observed only in the deferrated media with AT, but not in the media supplemented with PT or HT. In contrast, siderophores were definitely produced in the deferrated media with PT and HT, as well as in the media supplemented with AT. The siderophores proved to have the ability to remove iron directly from transferrin, but the washed whole cells expressing IsdA did not. In the bioassay, the growth of S. aureus on transferrin-bound iron was stimulated by the siderophores alone. These results demonstrate that the siderophore-mediated iron-acquisition system plays a dominant and essential role in the uptake of iron from transferrin, whereas the IsdA-mediated iron-acquisition system may play only an ancillary role in the uptake of iron from transferrin.
Asunto(s)
Hierro/metabolismo , Sideróforos/fisiología , Staphylococcus aureus/metabolismo , Transferrina/metabolismo , Complejo Receptor de Transferrina Bacteriana/fisiología , Staphylococcus aureus/crecimiento & desarrolloRESUMEN
Methylene blue (MB), a water-soluble cationic dye widely used in the clinic, is known to photosensitize the generation of cytotoxic singlet oxygen efficiently, and thus, has attracted interest as a potential drug for photodynamic therapy (PDT). However, its use for the in vivo PDT of cancer has been limited due to the inherently poor cell/tissue accumulation and low biological stability in the free molecular form. Here, we report a simple and biocompatible nanocomplex formulation of MB (NanoMB) that is useful for in vivo locoregional cancer treatment by PDT. NanoMB particles were constructed through the self-assembly of clinically usable molecules (MB, fatty acid and a clinically approved polymer surfactant) directed by the dual (electrostatic and hydrophobic) interactions between the ternary constituents. The nanocomplexed MB showed greatly enhanced cell internalization while keeping the photosensitization efficiency as high as free MB, leading to distinctive phototoxicity toward cancer cells. When administered to human breast cancer xenograft mice by peritumoral injection, NanoMB was capable of facile penetration into the tumor followed by cancer cell accumulation, as examined in vivo and histologically with the near-infrared fluorescence signal of MB. The quintuple PDT treatment by a combination of peritumorally injected NanoMB and selective laser irradiation suppressed the tumor volume efficaciously, demonstrating potential of NanoMB-based PDT as a biocompatible and safe method for adjuvant locoregional cancer treatment.
Asunto(s)
Azul de Metileno , Nanopartículas , Neoplasias/tratamiento farmacológico , Fotoquimioterapia , Fármacos Fotosensibilizantes , Animales , Línea Celular Tumoral , Supervivencia Celular/efectos de los fármacos , Femenino , Humanos , Luz , Azul de Metileno/administración & dosificación , Azul de Metileno/química , Azul de Metileno/uso terapéutico , Ratones Endogámicos BALB C , Nanopartículas/administración & dosificación , Nanopartículas/química , Nanopartículas/uso terapéutico , Neoplasias/patología , Ácido Oléico/química , Fármacos Fotosensibilizantes/administración & dosificación , Fármacos Fotosensibilizantes/química , Fármacos Fotosensibilizantes/uso terapéutico , Poloxámero/química , Oxígeno Singlete/química , Tensoactivos/química , Carga Tumoral/efectos de los fármacos , Ensayos Antitumor por Modelo de XenoinjertoRESUMEN
AlPO4-Al2O3 (Al/P > 9), prepared by impregnating (NH4)2HPO4 on Boehmite, showed high catalytic activity and durability for the hydrolytic decomposition of perfluoro compounds even in the presence of water and HF.
RESUMEN
The genus Peptoniphilus comprises butyrate-producing, nonsaccharolytic species that use peptone and amino acids as major energy sources. The novel Peptoniphilus sp. strain ChDC B134 (=KCOM 1628) was isolated from a human periapical abscess lesion. Here, we report the draft genome sequence of the strain.
RESUMEN
Ceramide, a major class of hair lipid, can help determine the physicochemical properties of human hairs such as the chemical diffusion barrier and water retention. In this study, we developed a quantitation method for ceramide and dihydroceramide, a saturated form of ceramide, in human hairs. Lipids were extracted with ethanol from human hairs spiked with N-oleoyl-D-erythro-C(17) sphingosine, an internal standard. Ceramide and dihydroceramide were resolved by TLC and deacylated by sphingolipid-ceramide deacylase to release sphingosine and dihydrosphingosine, respectively. The hair content of ceramide was measured by HPLC following derivatization with o-phthalaldehyde. The limits of detection and quantification for ceramide extracted from hair fibers were 0.1 and 1 pmol, respectively. The linear range of hair weight for determining ceramide and dihydroceramide contents was 1 to 50 mg, with R(2) values of 0.9695 and 0.9898, respectively. The recoveries of ceramide and dihydroceramide from intra-day and interday assays were 99.55% to 98.53%, respectively. Concentrations of dihydroceramide from the hair roots to distal tip ends ranged from 10.42 +/- 2.19 to 1.20 +/- 0.11 nmol/g hair, while those of ceramide ranged from 2.27 +/- 0.22 to 1.47 +/- 0.15 nmol/g hair. The present analytical method provides a simultaneous and reproducible quantification of ceramide and dihydroceramide, and may be used as a potential biomarker for lipid abnormality-related diseases.
Asunto(s)
Ceramidas/análisis , Cabello/química , Envejecimiento/fisiología , Biomarcadores/análisis , Cromatografía Líquida de Alta Presión , Cromatografía en Capa Delgada , Remoción de Radical Alquila , Humanos , Lípidos/química , Lípidos/aislamiento & purificación , Estándares de Referencia , Reproducibilidad de los Resultados , Caracteres Sexuales , Espectrometría de Fluorescencia , Esfingolípidos/químicaRESUMEN
We determined the ferrophilic characteristics of Vibrio vulnificus to evaluate the potential usefulness of iron chelation therapy for the prevention of V. vulnificus infection. Readily available non-transferrin-bound iron (NTBI) is required for the initiation of V. vulnificus growth under in vitro iron-limited conditions and human ex vivo conditions. NTBI aided efficient transferrin-bound iron (TBI) use by V. vulnificus, and the vulnibactin-mediated iron-uptake system was expressed after bacterial growth had been started by NTBI. V. vulnificus required higher NTBI levels for the initiation of growth, produced siderophores at lower levels, and used TBI less efficiently than other bacteria. In addition, the growth of V. vulnificus was inhibited by deferiprone, a clinically available iron chelator. These results show that V. vulnificus is a ferrophilic bacterium that requires higher NTBI levels than other pathogens and that iron chelation therapy might be an effective means of preventing the in vivo growth of V. vulnificus in susceptible patients.