Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 21
Filtrar
Más filtros










Base de datos
Intervalo de año de publicación
1.
Eur J Nutr ; 2024 May 04.
Artículo en Inglés | MEDLINE | ID: mdl-38703224

RESUMEN

OBJECTIVE: The aim of this study was to determine the associations between dietary diversity and risk of dyslipidemia in Japanese workers. METHODS: The cross-sectional study included 1399 participants aged 20-63 years and the longitudinal study included 751 participants aged 20-60 years in 2012-2013 (baseline) who participated at least once from 2013 to 2017 with cumulative participation times of 4.9 times. Dietary intake was assessed using a food frequency questionnaire, and dietary diversity score (DDS) was determined using the Quantitative Index for Dietary Diversity. Dyslipidemia was diagnosed when at least one of the following conditions was met: hypertriglyceridemia, high LDL-cholesterol, low HDL-cholesterol, high non-HDL-cholesterol, and a history of dyslipidemia. Multivariable logistic regression was used to calculate the odds ratios (ORs) and 95% confidence intervals (CIs) for dyslipidemia with control of confounding factors in cross-sectional analysis. Generalized estimating equations were used for calculating the ORs (95% CI) for dyslipidemia in the follow-up period according to the DDS at baseline with control of confounding factors in longitudinal analysis. RESULTS: Cross-sectional analysis showed that the highest DDS reduced the odds of dyslipidemia in men (OR [95% CI] in Tertile 3: 0.67 [0.48-0.95], p value = 0.023). In longitudinal analysis, a moderate DDS reduced the risk of dyslipidemia (OR [95% CI] in Tertile 2: 0.21 [0.07-0.60], p value = 0.003) in women. CONCLUSIONS: The results of cross-sectional analysis in this study suggest that the higher diversity of diet might reduce the presence of dyslipidemia in men and the results of longitudinal analysis suggest that a moderate DDS might reduce the risk of dyslipidemia in women. Further studies are needed since the results of cross-sectional and longitudinal analyses in this study were inconsistent.

2.
Parkinsonism Relat Disord ; 117: 105907, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37948832

RESUMEN

INTRODUCTION: KW-6356 is a novel selective adenosine A2A receptor antagonist/inverse agonist. We evaluated the efficacy and safety of KW-6356 as monotherapy in patients with early, untreated Parkinson's disease (PD). METHODS: This was a randomized, placebo-controlled, double-blind study conducted in Japan to investigate the efficacy and safety of once-daily KW-6356 (3 or 6 mg/day) orally administered as monotherapy for 12 weeks in patients with early PD (NCT02939391). The primary endpoint was the least squares means of change from baseline in the MDS-UPDRS Part III total score. RESULTS: Overall, 168 patients were randomized and treated (KW-6356 3 mg/day n = 55; 6 mg/day n = 58, placebo n = 55); Week 12 completion rates were >90% per group. LS mean [95% CI] changes from baseline to Week 12 in MDS-UPDRS Part III total scores were -5.37 [-7.25, -3.48] for 3 mg/day, -4.76 [-6.55, -2.96] for 6 mg/day and -3.14 [-4.97, -1.30] for placebo. Changes from baseline were larger for both KW-6356 groups than for the placebo group at all time points. Secondary endpoints supported the primary findings with larger changes in MDS-UPDRS Part II, Parts II + III, and Total scores in the KW-6356 groups than in the placebo group. Treatment was well-tolerated; the most common treatment-emergent adverse events with KW-6356 were constipation (n = 4 [7.3%] and n = 6 [10.3%] in the 3 and 6 mg/day groups, respectively) followed by nasopharyngitis (n = 4 [7.3%] and n = 5 [8.6%] in the 3 and 6 mg/day groups, respectively). CONCLUSION: KW-6356 monotherapy is well tolerated and more effective than placebo in patients with early, untreated PD.


Asunto(s)
Nasofaringitis , Enfermedad de Parkinson , Humanos , Enfermedad de Parkinson/tratamiento farmacológico , Agonismo Inverso de Drogas , Método Doble Ciego , Japón , Nasofaringitis/inducido químicamente , Antiparkinsonianos
3.
J Phys Ther Sci ; 35(6): 421-425, 2023 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-37266366

RESUMEN

[Purpose] This study aimed to clarify the relationship between one-eye visual deprivation; thus, interfering with stereoscopic perception, and movement and obtain insights on the influence of visual perception on movement to step over obstacles. [Participants and Methods] Participants were 25 healthy individuals. There were two conditions of visual perception (stationary and approaching conditions) and two additional conditions of binocular and monocular visions. Under the four conditions, participants were asked to step over an obstacle immediately after a 90° turn while walking. Distance between the foot and obstacle, foot pressure distribution, and stance phase time were measured. [Results] Toe clearance was lower in the approaching condition than that in the binocular stationary condition. The trajectory length ratio was greater in the approaching condition than that in the stationary condition, and heel-ground contact, metatarsal-ground contact, and stance times were all shorter in the binocular condition. Additionally, heel contact, midfoot contact, metatarsal contact, and stance times were shorter in the approaching condition than that in the stationary condition. [Conclusion] In walking with a 90° turn, the binocular approaching condition provided more visual information and positively affected motor control of movements to step over an obstacle.

4.
Environ Sci Pollut Res Int ; 30(35): 83950-83960, 2023 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-37351753

RESUMEN

Antibiotic-resistant bacteria (ARBs) can now be detected not only in clinical institutions but also in wastewater treatment plants (WWTPs), extending the range of emergence to residential areas. In this study, we investigated the change of antibiotic-resistant Escherichia coli (E. coli) and other coliforms in each treatment process at WWTPs. Throughout the treatment process, the numbers of E. coli and other coliforms were significantly reduced to less than 5.7 ± 0.5 CFU/100 ml and 2.4 ± 0.0×102 CFU/100 ml, respectively. However, ESBL-producing E. coli and other coliforms were detected in each treatment process (even after chlorination) at 5.6% and 4.8%, compared to the total E. coli and other coliforms counts. Then, ESBL-producing-related genes were identified via PCR analyses, and the most predominant gene was CTX-M-9 in both E. coli (47.2%) and other coliforms (47.3%). Although actual WWTPs greatly reduced the number of bacteria, the relative prevalence of ESBL-producing bacteria was increased, suggesting that ESBL-producing bacteria remain in the effluent at minimal concentrations and could be diffusing to water bodies.


Asunto(s)
Escherichia coli , Purificación del Agua , Escherichia coli/genética , Prevalencia , Antagonistas de Receptores de Angiotensina , beta-Lactamasas/genética , Inhibidores de la Enzima Convertidora de Angiotensina , Antibacterianos/farmacología
5.
J Phys Ther Sci ; 35(5): 351-354, 2023 May.
Artículo en Inglés | MEDLINE | ID: mdl-37131344

RESUMEN

[Purpose] The purpose of this study was to clarify whether the presence of obstructions changes the crossing motion during walking based on the visual perception of obstacles. [Participants and Methods] We included 25 healthy university students as the participants in this study. They were asked to step over obstacles while walking under two conditions i.e., with obstruction and without obstruction. We analyzed the distance between the foot and obstacle (clearance), trajectory of foot pressure movement and distribution as measured by a foot pressure distribution measurement system, and stance phase time. [Results] No significant differences were found between the two conditions for either clearance or foot pressure distribution. In other words, no difference in crossing motion was observed after visual recognition of the obstacle, both in the presence or absence of the obstruction. [Conclusion] The results suggest that no differences exist in the accuracy of recognizing visual information about an obstacle through different mechanisms of selective visual attention.

6.
Asia Pac J Clin Nutr ; 31(3): 433-440, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36173215

RESUMEN

BACKGROUND AND OBJECTIVES: We examined how food choice motives and dietary habits changed during the COVID-19 pandemic. METHODS AND STUDY DESIGN: Four hundred elderly Japanese completed an online questionnaire in early May in 2021. Participants were retrospectively asked about their intake of food groups and food choice motives before and during the COVID-19 pandemic. Dietary diversity was determined using the dietary variety score calculated from the food frequency questionnaire with 10 food groups. The importance of each of the nine food choice motives for elderly people was assessed. Each scores ranged from 1 to 5. Changes in food choice motives and dietary behaviors during the COVID-19 pandemic were assessed using the paired t-test and a general linear model. RESULTS: Among the food choice motives, scores for the importance of weight control, physical well-being and economical efficiency significantly increased in both sexes (all p<0.05). Dietary diversity score was lower during the COVID-19 pandemic than that before the pandemic in women (p=0.019), but there was no difference in men. In the multivariate adjustment model, physical well-being and economical efficiency were shown to have significant positive associations with the COVID-19 pandemic in women (p=0.034 and 0.009, respectively). In contrast, eating out was shown to have a significant inverse association with the COVID-19 pandemic in women (p=0.009). CONCLUSIONS: The findings suggest that the COVID-19 pandemic was associated with an increase in some food choice motives and a decrease in the frequency of eating out among elderly female Japanese.


Asunto(s)
COVID-19 , Pandemias , Anciano , COVID-19/epidemiología , Dieta , Conducta Alimentaria , Femenino , Humanos , Internet , Japón/epidemiología , Masculino , Estudios Retrospectivos , Encuestas y Cuestionarios
7.
J Radiat Res ; 60(6): 812-817, 2019 Nov 22.
Artículo en Inglés | MEDLINE | ID: mdl-31553454

RESUMEN

During irradiation sessions for brain tumors or head and neck cancers, some patients experience abnormal olfactory sensations. To date, the frequency of such sensations during these treatment sessions has not been investigated. We analyzed abnormal olfactory sensations in patients who underwent radiation therapy at our institution for primary brain tumors, excluding malignant lymphoma, between January 2009 and January 2018. A total of 191 patients who were awake during radiation treatment and capable of communicating were analyzed in this retrospective medical study. Of these patients, 7 were aware of olfactory sensations during irradiation. The median age of these 7 patients was 13 (range 8-47) years, Six were <20 years of age, accounting for 10% of the total population of similar age (n = 60). However, only 1 of 131 patients aged ≥20 years complained of strange olfactory sensations. Four of seven patients had germ cell tumors, but none had a medulloblastoma. We investigated patients who experienced light sensation, as an internal standard to ascertain the accuracy of this study. Only 10 patients experienced light sensation during their irradiation sessions. This suggests that the frequency of these sensations was possibly underestimated in our study. In conclusion, a considerable number of patients experienced unusual olfactory sensations during radiation treatment. Further prospective studies on abnormal olfactory sensations during irradiation are needed to clarify the underlying mechanism of this sensation.


Asunto(s)
Neoplasias Encefálicas/fisiopatología , Neoplasias Encefálicas/radioterapia , Percepción Olfatoria , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Niño , Preescolar , Femenino , Humanos , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Adulto Joven
8.
J Exp Bot ; 70(21): 6127-6139, 2019 11 18.
Artículo en Inglés | MEDLINE | ID: mdl-31498865

RESUMEN

Ribulose-1,5-bisphosphate carboxylase/oxygenase (RuBisCO) is considered to be the main enzyme determining the rate of photosynthesis. The small subunit of the protein, encoded by the rbcS gene, has been shown to influence the catalytic efficiency, CO2 specificity, assembly, activity, and stability of RuBisCO. However, the evolution of the rbcS gene remains poorly studied. We inferred the phylogenetic tree of the rbcS gene in angiosperms using the nucleotide sequences and found that it is composed of two lineages that may have existed before the divergence of land plants. Although almost all species sampled carry at least one copy of lineage 1, genes of lineage 2 were lost in most angiosperm species. We found the specific residues that have undergone positive selection during the evolution of the rbcS gene. We detected intensive coevolution between each rbcS gene copy and the rbcL gene encoding the large subunit of RuBisCO. We tested the role played by each rbcS gene copy on the stability of the RuBisCO protein through homology modelling. Our results showed that this evolutionary constraint could limit the level of divergence seen in the rbcS gene, which leads to the similarity among the rbcS gene copies of lineage 1 within species.


Asunto(s)
Evolución Molecular , Duplicación de Gen , Magnoliopsida/genética , Familia de Multigenes , Proteínas de Plantas/genética , Codón/genética , Conversión Génica , Funciones de Verosimilitud , Modelos Moleculares , Filogenia , Proteínas de Plantas/química , Estabilidad Proteica , Selección Genética , Spinacia oleracea/metabolismo , Termodinámica
9.
Bioorg Med Chem ; 27(15): 3334-3338, 2019 08 01.
Artículo en Inglés | MEDLINE | ID: mdl-31204230

RESUMEN

Cytosporolide (Cytos) A-C, isolated from the fungus Cytospora sp., have anti-microbial activity, but their molecular targets in mammalian cells are unknown. We have previously reported the total synthesis of Cytos A by biomimetic hetero-Diels-Alder reaction. In this study, to examine the novel bioactivity of Cytos, we synthesized Cytos C and measured cell growth-inhibiting activities of 7 compounds, including Cytos A and C, in several human cancer cell lines. Among these compounds, Cytos C and tetradeoxycytosporolide A (TD-Cytos A), a model compound for the synthesis of Cytos A, had anti-proliferative effects on cancer cells, and TD-Cytos A exhibited stronger activity than Cytos C. In vitro topoisomerase-mediated DNA relaxing experiments showed that TD-Cytos A inhibited the activities of topoisomerase I and II, whereas Cytos C targeted only topoisomerase I. These data suggest that the anti-proliferative activities of Cytos correlate with the inhibition of topoisomerases and implicated TD-Cytos A as a novel anti-cancer drug that suppresses the activities of topoisomerase I and II.


Asunto(s)
Antineoplásicos/farmacología , ADN-Topoisomerasas de Tipo I/metabolismo , Proteínas de Unión a Poli-ADP-Ribosa/antagonistas & inhibidores , Sesquiterpenos/farmacología , Inhibidores de Topoisomerasa/farmacología , Antineoplásicos/síntesis química , Antineoplásicos/química , Proliferación Celular/efectos de los fármacos , ADN-Topoisomerasas de Tipo II/metabolismo , Relación Dosis-Respuesta a Droga , Ensayos de Selección de Medicamentos Antitumorales , Humanos , Estructura Molecular , Proteínas de Unión a Poli-ADP-Ribosa/metabolismo , Sesquiterpenos/síntesis química , Sesquiterpenos/química , Relación Estructura-Actividad , Inhibidores de Topoisomerasa/síntesis química , Inhibidores de Topoisomerasa/química , Células Tumorales Cultivadas
10.
Xenotransplantation ; 26(1): e12468, 2019 01.
Artículo en Inglés | MEDLINE | ID: mdl-30375053

RESUMEN

The ultimate goal of regenerative medicine is the transplantation of a target organ generated by the patient's own cells. Recently, a method of organ generation using pluripotent stem cells (PSCs) and blastocyst complementation was reported. This approach is based on chimeric animal generation using an early embryo and PSCs, and the contribution of PSCs to the target organ is key to the method's success. However, the contribution rate of PSCs in target organs generated by different chimeric animal generation methods remains unknown. In this study, we used 8-cell embryo aggregation, 8-cell embryo injection, and blastocyst injection to generate interspecies chimeric mice using rat embryonic stem (ES) cells and then investigated the differences in the contribution rate of the rat ES cells. The rate of chimeric mouse generation was the highest using blastocyst injection, followed in order by 8-cell embryo injection and 8-cell embryo aggregation. However, the contribution rate of rat ES cells was the highest in chimeric neonates generated by 8-cell embryo injection, and the difference was statistically significant in the liver. Live functionality was confirmed by analyzing the expression of rat hepatocyte-derived drug-metabolizing enzyme. Collectively, these findings indicate that the 8-cell embryo injection method is the most suitable for generation of PSC-derived organs via chimeric animal generation, particularly for the liver.


Asunto(s)
Blastocisto/citología , Agregación Celular/fisiología , Células Madre Embrionarias/citología , Células Madre Pluripotentes/citología , Trasplante Heterólogo , Animales , Diferenciación Celular/fisiología , Femenino , Ratones , Ratas
11.
Kidney Int Rep ; 2(3): 359-365, 2017 May.
Artículo en Inglés | MEDLINE | ID: mdl-29142965

RESUMEN

INTRODUCTION: In hemodialysis patients on ferric citrate hydrate, the increase in ferritin level is mainly due to the administration of the compound. We investigated possible other factors associated with ferritin level and how erythropoietin resistance index and erythropoiesis in those patients were affected. We looked at ferritin-elevating factors using data from a Japanese phase III long-term clinical trial of ferric citrate hydrate. METHODS: The factors with a strong association with ferritin levels at week 28 were selected by the process of variable selection. In addition, selected factors were analyzed by Mixed Model for Repeated Measurement. Subjects were divided into 3 groups by quantiles (

12.
Sci Rep ; 6: 36782, 2016 11 10.
Artículo en Inglés | MEDLINE | ID: mdl-27830776

RESUMEN

There is no blood bank for pet animals. Consequently, veterinarians themselves must obtain "blood" for transfusion therapy. Among the blood components, serum albumin and red blood cells (RBCs) are particularly important to save lives. This paper reports the synthesis, structure, and properties of artificial blood for the exclusive use of dogs. First, recombinant canine serum albumin (rCSA) was produced using genetic engineering with Pichia yeast. The proteins showed identical features to those of the native CSA derived from canine plasma. Furthermore, we ascertained the crystal structure of rCSA at 3.2 Å resolution. Pure rCSA can be used widely for numerous clinical and pharmaceutical applications. Second, hemoglobin wrapped covalently with rCSA, hemoglobin-albumin cluster (Hb-rCSA3), was synthesized as an artificial O2-carrier for the RBC substitute. This cluster possesses satisfactorily negative surface net charge (pI = 4.7), which supports enfolding of the Hb core by rCSA shells. The anti-CSA antibody recognized the rCSA exterior quantitatively. The O2-binding affinity was high (P50 = 9 Torr) compared to that of the native Hb. The Hb-rCSA3 cluster is anticipated for use as an alternative material for RBC transfusion, and as an O2 therapeutic reagent that can be exploited in various veterinary medicine situations.


Asunto(s)
Sustitutos Sanguíneos/química , Hemoglobinas/química , Albúmina Sérica/química , Animales , Cristalografía por Rayos X , Perros , Modelos Moleculares , Oxígeno/química , Unión Proteica , Conformación Proteica en Hélice alfa , Dominios Proteicos , Estabilidad Proteica
13.
PLoS One ; 11(2): e0149526, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-26895315

RESUMEN

A hemoglobin wrapped covalently by three human serum albumins, a Hb-HSA3 cluster, is an artificial O2-carrier with the potential to function as a red blood cell substitute. This paper describes the synthesis and O2-binding properties of new hemoglobin‒albumin clusters (i) bearing four HSA units at the periphery (Hb-HSA4, large-size variant) and (ii) containing an intramolecularly crosslinked Hb in the center (XLHb-HSA3, high O2-affinity variant). Dynamic light scattering measurements revealed that the Hb-HSA4 diameter is greater than that of either Hb-HSA3 or XLHb-HSA3. The XLHb-HSA3 showed moderately high O2-affinity compared to the others because of the chemical linkage between the Cys-93(ß) residues in Hb. Furthermore, the blood circulation behavior of 125I-labeled clusters was investigated by assay of blood retention and tissue distribution after intravenous administration into anesthetized rats. The XLHb-HSA3 was metabolized faster than Hb-HSA3 and Hb-HSA4. Results suggest that the molecular structure of the protein cluster is a factor that can influence in vivo circulation behavior.


Asunto(s)
Sustitutos Sanguíneos/química , Hemoglobinas/química , Oxígeno/metabolismo , Albúmina Sérica/química , Animales , Circulación Sanguínea , Sustitutos Sanguíneos/síntesis química , Sustitutos Sanguíneos/metabolismo , Bovinos , Hemoglobinas/metabolismo , Humanos , Masculino , Estructura Molecular , Complejos Multiproteicos/química , Complejos Multiproteicos/metabolismo , Ratas Wistar , Albúmina Sérica/metabolismo , Relación Estructura-Actividad , Distribución Tisular
14.
Ther Innov Regul Sci ; 50(6): 823-832, 2016 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-30231737

RESUMEN

BACKGROUND: While benefit-risk (B-R) assessment in the real-world setting is an important challenge for pharmacovigilance, few studies have explored this approach. To investigate the utility and limitations of B-R assessment using a health care database by applying the Benefit Risk Action Team (BRAT) framework, we have conducted a case study with erythropoietin agents. METHODS: Postmarketing data from the Medical Data Vision health care database were used in a B-R comparison between methoxy polyethylene glycol-epoetin beta (continuous erythropoietin receptor activator; C.E.R.A.) and other erythropoiesis-stimulating agents (ESAs). Data were from patients with chronic kidney disease (CKD) treated with C.E.R.A. (n = 131: nondialysis, 109; hemodialysis, 22) or other ESAs (n = 542: nondialysis, 327; hemodialysis, 215) between July 2011 and March 2014. RESULTS: The B-R profile for C.E.R.A. appeared to be similar to that for other ESAs in both nondialysis and hemodialysis patients with CKD, when benefits and risks were mainly assessed in terms of odds ratios. Despite various point estimates and confidence intervals for each outcome, the results of subgroup analyses showed no notable differences from the overall analysis in B-R assessment. CONCLUSIONS: B-R assessment can be performed using the BRAT framework with a health care database, but limitations exist when using a single data source. Care should be taken when selecting data for extraction and defining outcomes of interest. Further research is necessary to facilitate practical application of this approach.

15.
Sci Rep ; 5: 12778, 2015 Jul 29.
Artículo en Inglés | MEDLINE | ID: mdl-26220366

RESUMEN

A hemoglobin (Hb) wrapped covalently by human serum albumins (HSAs), a core-shell structured hemoglobin-albumin cluster designated as "HemoAct", is an O2-carrier designed for use as a red blood cell (RBC) substitute. This report describes the blood compatibility, hemodynamic response, and pharmacokinetic properties of HemoAct, and then explains its preclinical safety. Viscosity and blood cell counting measurements revealed that HemoAct has good compatibility with whole blood. Intravenous administration of HemoAct into anesthetized rats elicited no unfavorable increase in systemic blood pressure by vasoconstriction. The half-life of (125)I-labeled HemoAct in circulating blood is markedly longer than that of HSA. Serum biochemical tests conducted 7 days after HemoAct infusion yielded equivalent values to those observed in the control group with HSA. Histopathologic inspections of the vital organs revealed no marked abnormality in their tissues. All results indicate that HemoAct has sufficient preclinical safety as an alternative material for RBC transfusion.


Asunto(s)
Sustitutos Sanguíneos/química , Eritrocitos/química , Hemoglobinas/química , Albúmina Sérica/química , Administración Intravenosa , Animales , Área Bajo la Curva , Pruebas de Coagulación Sanguínea , Sustitutos Sanguíneos/administración & dosificación , Sustitutos Sanguíneos/farmacocinética , Transfusión de Eritrocitos/métodos , Hemodinámica , Hemoglobinas/administración & dosificación , Hemoglobinas/farmacocinética , Humanos , Masculino , Tasa de Depuración Metabólica , Ratas Wistar , Reproducibilidad de los Resultados , Albúmina Sérica/administración & dosificación , Albúmina Sérica/farmacocinética , Factores de Tiempo , Distribución Tisular , Viscosidad
16.
Free Radic Biol Med ; 85: 219-27, 2015 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-25881551

RESUMEN

p-Cresol that is produced by the intestinal microbiota from the amino acid tyrosine is found at millimolar concentrations in the human feces. The effects of this metabolite on colonic epithelial cells were tested in this study. Using the human colonic epithelial HT-29 Glc(-/+) cell line, we found that 0.8mM p-cresol inhibits cell proliferation, an effect concomitant with an accumulation of the cells in the S phase and with a slight increase of cell detachment without necrotic effect. At this concentration, p-cresol inhibited oxygen consumption in HT-29 Glc(-/+) cells. In rat normal colonocytes, p-cresol also inhibited respiration. Pretreatment of HT-29 Glc(-/+) cells with 0.8mM p-cresol for 1 day resulted in an increase of the state 3 oxygen consumption and of the cell maximal respiratory capacity with concomitant increased anion superoxide production. At higher concentrations (1.6 and 3.2mM), p-cresol showed similar effects but additionally increased after 1 day the proton leak through the inner mitochondrial membrane, decreasing the mitochondrial bioenergetic activity. At these concentrations, p-cresol was found to be genotoxic toward HT-29 Glc(-/+) and also LS-174T intestinal cells. Lastly, a decreased ATP intracellular content was observed after 3 days treatment. p-Cresol at 0.8mM concentration inhibits colonocyte respiration and proliferation. In response, cells can mobilize their "respiratory reserve." At higher concentrations, p-cresol pretreatment uncouples cell respiration and ATP synthesis, increases DNA damage, and finally decreases the ATP cell content. Thus, we have identified p-cresol as a metabolic troublemaker and as a genotoxic agent toward colonocytes.


Asunto(s)
Colon/efectos de los fármacos , Cresoles/toxicidad , Mucosa Intestinal/efectos de los fármacos , Mutágenos/toxicidad , Células HT29 , Humanos
17.
Drug Discov Ther ; 8(5): 212-7, 2014 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-25382556

RESUMEN

In eukaryotes, the Mediator complex is an essential transcriptional cofactor of RNA polymerase II (Pol II). In humans, it contains up to 30 subunits and consists of four modules: head, middle, tail, and CDK/Cyclin. One of the subunits, MED15, is located in the tail module, and was initially identified as Gal11 in budding yeast, where it plays an essential role in the transcriptional regulation of galactose metabolism with the potent transcriptional activator Gal4. For this reason, we investigated the function of the human MED15 subunit (hMED15) in transcriptional activation. First, we measured the effect of hMED15 knockdown on cell growth in HeLa cells. The growth rate was greatly reduced. By immunostaining, we observed the colocalization of hMED15 with the general transcription factors TFIIE and TFIIH in the nucleus. We measured the effects of siRNA-mediated knockdown of hMED15 on transcriptional activation using two different transcriptional activators, VP16 and SREBP1a. Treatment with siRNAs reduced transcriptional activation, and this reduction could be rescued by overexpression of HA/Flag-tagged, wild-type hMED15. To investigate hMED15 localization, we treated human MCF-7 cells with the MDM2 inhibitor Nutlin-3, thus inducing p21 transcription. We found that hMED15 localized to both the p53 binding site and the p21 promoter region, along with TFIIE and TFIIH. These results indicate that hMED15 promotes transcriptional activation.


Asunto(s)
Glicina/análogos & derivados , Pirroles/farmacología , Activación Transcripcional/efectos de los fármacos , Núcleo Celular/efectos de los fármacos , Glicina/genética , Glicina/farmacología , Células HeLa , Humanos , Imidazoles/farmacología , Piperazinas/farmacología , Plásmidos/efectos de los fármacos , Plásmidos/genética , ARN Interferente Pequeño , Factor de Transcripción TFIIH/biosíntesis , Factor de Transcripción TFIIH/genética , Factores de Transcripción TFII/biosíntesis , Factores de Transcripción TFII/genética
18.
PLoS One ; 9(10): e110541, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-25310133

RESUMEN

A covalent core-shell structured protein cluster composed of hemoglobin (Hb) at the center and human serum albumins (HSA) at the periphery, Hb-HSAm, is an artificial O2 carrier that can function as a red blood cell substitute. Here we described the preparation of a novel Hb-HSA3 cluster with antioxidant activities and its O2 complex stable in aqueous H2O2 solution. We used an approach of incorporating a Pt nanoparticle (PtNP) into the exterior HSA unit of the cluster. A citrate reduced PtNP (1.8 nm diameter) was bound tightly within the cleft of free HSA with a binding constant (K) of 1.1×10(7) M(-1), generating a stable HSA-PtNP complex. This platinated protein showed high catalytic activities for dismutations of superoxide radical anions (O2•-) and hydrogen peroxide (H2O2), i.e., superoxide dismutase and catalase activities. Also, Hb-HSA3 captured PtNP into the external albumin unit (K = 1.1×10(7) M(-1)), yielding an Hb-HSA3(PtNP) cluster. The association of PtNP caused no alteration of the protein surface net charge and O2 binding affinity. The peripheral HSA-PtNP shell prevents oxidation of the core Hb, which enables the formation of an extremely stable O2 complex, even in H2O2 solution.


Asunto(s)
Albúminas/metabolismo , Antioxidantes , Sustitutos Sanguíneos , Hemoglobinas/metabolismo , Nanopartículas , Oxígeno/metabolismo , Albúminas/química , Sitios de Unión , Hemoglobinas/química , Humanos , Peróxido de Hidrógeno/antagonistas & inhibidores , Concentración 50 Inhibidora , Cinética , Modelos Moleculares , Conformación Molecular , Nanopartículas/química , Nanopartículas/ultraestructura , Unión Proteica , Superóxidos/antagonistas & inhibidores
19.
Nat Commun ; 3: 1035, 2012.
Artículo en Inglés | MEDLINE | ID: mdl-22948817

RESUMEN

Magnetic ferrites such as Fe(3)O(4) and Fe(2)O(3) are extensively used in a range of applications because they are inexpensive and chemically stable. Here we show that rhodium-substituted ε-Fe(2)O(3), ε-Rh(x)Fe(2-x)O(3) nanomagnets prepared by a nanoscale chemical synthesis using mesoporous silica as a template, exhibit a huge coercive field (H(c)) of 27 kOe at room temperature. Furthermore, a crystallographically oriented sample recorded an H(c) value of 31 kOe, which is the largest value among metal-oxide-based magnets and is comparable to those of rare-earth magnets. In addition, ε-Rh(x)Fe(2-x)O(3) shows high frequency millimetre wave absorption up to 209 GHz. ε-Rh(0.14)Fe(1.86)O(3) exhibits a rotation of the polarization plane of the propagated millimetre wave at 220 GHz, which is one of the promising carrier frequencies (the window of air) for millimetre wave wireless communications.

20.
Nutr Res ; 32(2): 116-23, 2012 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-22348460

RESUMEN

Oxidative stress modulates the osteoclast differentiation via redox systems, and thioredoxin 1 (Trx) promotes the osteoclast formation by regulating the activity of transcription factors. The function of Trx is known to be regulated by its binding partner, thioredoxin-interacting protein (TXNIP). We previously reported that the expression of TXNIP gene is strongly induced by a rare sugar D-allose. In this study, we tested the hypothesis that D-allose could inhibit the osteoclast differentiation by regulating the Trx function. We used a murine Raw264 cell line that differentiates to the osteoclast by the receptor activator of nuclear factor-κB ligand (RANKL) treatment. The effect of sugars was evaluated by tartrate-resistant acid phosphatase staining. The expression and localization of TXNIP and Trx protein were examined by Western blotting and immunohistochemisty. The activity of the nuclear factor-κB, nuclear factor of activated T cells, and activator protein 1 transcription factors was measured by the luciferase reporter assay. The addition of D-allose (25 mmol/L) inhibited the osteoclast differentiation down to 9.53% ± 1.27% of a receptor activator of nuclear factor-κB ligand-only treatment. During the osteoclast differentiation, a significant increase of TNXIP was observed by D-allose treatment. The immunohistochemical analysis showed that both Trx and TXNIP existed in the nucleus in preosteoclasts and osteoclasts. Overexpression of TXNIP by plasmid transfection also inhibited the osteoclast formation, indicating the functional importance of TXNIP for the osteoclast differentiation. Transcriptional activity of the activator protein 1, nuclear factor-κB, and nuclear factor of activated T cells, known to be modulated by Trx, were inhibited by D-allose. In conclusion, our data indicate that D-allose is a strong inhibitor of the osteoclast differentiation, and this effect could be caused by TXNIP induction and a resulting inhibition of the Trx function.


Asunto(s)
Proteínas Portadoras/metabolismo , Diferenciación Celular/efectos de los fármacos , Regulación de la Expresión Génica/efectos de los fármacos , Glucosa/farmacología , Osteoclastos/efectos de los fármacos , Tiorredoxinas/metabolismo , Transcripción Genética/efectos de los fármacos , Animales , Proteínas Portadoras/genética , Línea Celular , Núcleo Celular , Ratones , Osteoclastos/fisiología , Estrés Oxidativo/fisiología , Plásmidos , Ligando RANK/metabolismo , Ligando RANK/farmacología , Coloración y Etiquetado , Tiorredoxinas/genética , Factores de Transcripción/metabolismo , Transfección
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA
...