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1.
Phys Chem Chem Phys ; 23(11): 6509-6525, 2021 Mar 21.
Artículo en Inglés | MEDLINE | ID: mdl-33688862

RESUMEN

Recently, polycyclic aromatic hydrocarbons (PAHs) and oxygenated PAHs (OPAHs) have been attracting considerable attention owing to their high toxicity. Understanding their formation mechanism during combustion processes is important to control their emission. However, there are few studies that have quantitatively investigated OPAH formation in the fuel-rich oxidation of hydrocarbons, despite the availability of several studies on PAH formation. In this study, benzofuran and dibenzofuran as OPAHs were quantified in the fuel-rich oxidation of toluene using a flow reactor at atmospheric pressure in a temperature range of 1050-1350 K at equivalence ratios from 3.0 to 12.0 and residence times from 0.2 to 1.5 s. In addition to benzofuran and dibenzofuran, 4 types of monocyclic aromatic hydrocarbons and 19 types of PAHs were also evaluated. The experimental data obtained in this study were compared with those of the ethylene oxidation performed in our previous study. The existing kinetic model for PAH growth was modified based on several theoretical studies to predict the behavior of OPAHs with furan structures. The modified model showed significant improvements in the prediction of benzofuran and dibenzofuran formation. Based on the rate of production and sensitivity analysis using the modified model, the dominant reaction pathways of benzofuran and dibenzofuran were investigated.

2.
Artículo en Inglés | MEDLINE | ID: mdl-33445431

RESUMEN

The increasing healthcare cost imposes a large economic burden for the Japanese government. Predicting the healthcare cost may be a useful tool for policy making. A database of the area-basis public health insurance of one city was analyzed to predict the medical healthcare cost by the dental healthcare cost with a machine learning strategy. The 30,340 subjects who had continued registration of the area-basis public health insurance of Ebina city during April 2017 to September 2018 were analyzed. The sum of the healthcare cost was JPY 13,548,831,930. The per capita healthcare cost was JPY 446,567. The proportion of medical healthcare cost, medication cost, and dental healthcare cost was 78%, 15%, and 7%, respectively. By the results of the neural network model, the medical healthcare cost proportionally depended on the medical healthcare cost of the previous year. The dental healthcare cost of the previous year had a reducing effect on the medical healthcare cost. However, the effect was very small. Oral health may be a risk for chronic diseases. However, when evaluated by the healthcare cost, its effect was very small during the observation period.


Asunto(s)
Costo de Enfermedad , Costos de la Atención en Salud , Bases de Datos Factuales , Humanos , Seguro de Salud , Japón
3.
Biol Pharm Bull ; 44(1): 7-17, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33390552

RESUMEN

Vitamin K2 is suggested to have a suppressive effect on the peripheral blood mononuclear cells (PBMCs) of pediatric atopic dermatitis patients. We examined the molecular targets of vitamin K2 to suppress proliferation and cytokine production in T-cell mitogen-activated PBMCs of atopic dermatitis patients from the viewpoint of mitogen-activated protein kinase signaling molecules. The study population included 16 pediatric vitamin K2 patients and 21 healthy subjects. The effect of vitamin K2 on concanavalin A-activated PBMC proliferation was evaluated by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) and cell counting assays. T-helper (Th)1/Th2/Th17 cytokine profiles in plasma and PBMC-culture supernatants were analyzed by a cytometric beads array assay. Mitogen-activated protein kinase signaling molecules in concanavalin A-activated PBMCs were examined by enzyme-linked immunosorbent assay (ELISA) assays. At 10-100 µM, vitamin K2 significantly suppressed the proliferation of mitogen-activated PBMCs derived from atopic dermatitis patients and healthy subjects (p < 0.05). The interleukin (IL)-10 concentrations in plasma and the PBMC culture supernatants of atopic dermatitis patients were significantly higher than those of healthy subjects (p < 0.05). The IL-2 concentrations in the culture supernatants of atopic dermatitis PBMCs were significantly lower than those of healthy PBMCs (p < 0.05). Vitamin K2 significantly inhibited the IL-17A, IL-10, and tumor necrosis factor α (TNF-α) production (p < 0.05), and increased the IL-2 production (p < 0.01) in the culture supernatant of atopic dermatitis PBMCs. At 10-100 µM, vitamin K2 markedly decreased the of Mek1, extracellular signal-regulated kinases (ERK)1/2 mitogen-activated protein kinase, and SAPK/c-Jun N-terminal kinase (JNK) expression in atopic dermatitis PBMCs (p < 0.05). Vitamin K2 is suggested to attenuate activated T-cell immunity in atopic dermatitis patients through the inhibition of mitogen-activated protein kinase-Mek1-ERK1/2 and SAPK/JNK signaling pathways.

4.
J Radiat Res ; 62(2): 186-197, 2021 Mar 10.
Artículo en Inglés | MEDLINE | ID: mdl-33341899

RESUMEN

We used the method proposed by Schneider et al. Theor Biol Med Model 2011;8:27, to clarify how the radiation-induced secondary cancer incidence rate changes in patients after proton craniospinal irradiation (CSI) without and with vertebral-body-sparing (VBS). Eight patients aged 3-15 years who underwent proton CSI were enrolled in the study. For each case, two types of plan without and with VBS in the target were compared. The prescribed doses were assumed to be 23.4 Gy relative biological effectiveness (RBE) and 36 Gy (RBE). Using the dose-volume histograms of the two plans, the lifetime attributable risk (LAR) was calculated by both methods for each patient based on the dose data calculated using an XiO-M treatment planning system. Eight organs were analyzed as follows: lung, colon, stomach, small intestine, liver, bladder, thyroid and bone. When the prescribed dose used was 23.4 Gy (RBE), the average LAR differences and the average number needed to treat (NNT) between proton CSI without and with VBS were 4.04 and 24.8, respectively, whereas the average LAR difference and the average NNT were larger at 8.65 and 11.6, respectively, when the prescribed dose of 36 Gy (RBE) was used. The LAR for radiation-induced secondary cancer was significantly lower in proton CSI with VBS than without VBS in pediatric patients, especially for the colon, lung, stomach and thyroid. The results of this study could serve as reference data when considering how much of vertebral bodies should be included when performing proton CSI according to age in clinical settings.

5.
Nutrients ; 12(9)2020 Sep 21.
Artículo en Inglés | MEDLINE | ID: mdl-32967313

RESUMEN

Compromised oral health can alter food choices. Poor masticatory function leads to imbalanced food intake and undesirable nutritional status. The associations among nutritional status, oral health behavior, and self-assessed oral functions status were investigated using a community-based survey. In total, 701 subjects more than 50 years old living Ebina city located southwest of the capital Tokyo were investigated. The number of remaining teeth was counted by dental hygienists. Oral health behavior and self-assessed oral functions were evaluated by oral frailty checklist. Nutritional status was evaluated by the brief-type self-administered diet history questionnaire using Dietary Reference Intakes for Japanese as reference. More than 80% of subjects' intakes of vitamin B12, pantothenic acid, copper, and proteins were sufficient. In contrast, only 19% of subjects' intake of vitamin A was sufficient and 35.5% for vitamin B1. More than 90% of subjects' intakes of vitamin D and vitamin K were sufficient. Only 35.5% of subjects' intakes of dietary fiber were sufficient. Overall, 88.9% of subjects had excess salt. The number of remaining teeth was not correlated with nutritional intakes. Oral health behavior significantly correlated with nutritional intakes. Oral functions are important for food choice; however, oral functions were not directly correlated with nutritional intakes. Comprehensive health instructions including nutrition and oral health education is necessary for health promotion.

6.
Chemistry ; 26(17): 3698-3702, 2020 Mar 23.
Artículo en Inglés | MEDLINE | ID: mdl-31903635

RESUMEN

It has been established that a cationic rhodium(I)/P-phos complex catalyzes the asymmetric [2+2+2] cycloaddition of 1,6-enynes with racemic secondary allylic alcohols to produce the corresponding chiral bicyclic cyclohexenes, possessing three stereogenic centers, as a single diastereomer with excellent ee values. Mechanistic experiments revealed that the present cycloaddition proceeds through the kinetic resolution of the racemic secondary allylic alcohols, in which one enantiomer preferentially reacts with the 1,6-enyne.

7.
J Child Neurol ; 35(3): 208-214, 2020 03.
Artículo en Inglés | MEDLINE | ID: mdl-31709864

RESUMEN

OBJECTIVE: The present study aimed to determine whether granzymes are implicated in the pathogenesis of infection-associated acute encephalopathy (AE). METHODS: We investigated granzyme and cytokine levels in the cerebrospinal fluid of patients with acute encephalopathy or complex febrile seizures (cFS). A total of 24 acute encephalopathy patients and 22 complex febrile seizures patients were included in the present study. Levels of granzymes A and B were measured using enzyme-linked immunosorbent assay, and levels of tumor necrosis factor α (TNF-α), interferon-γ (IFN-γ), interleukin 1ß (IL-1ß), IL-1 receptor antagonist (IL-1RA), IL-4, IL-6, IL-8, and IL-10 were assessed using the Bio-Plex suspension array system. RESULTS: Cerebrospinal fluid levels of granzyme A were significantly higher, and those of TNF-α and IL-1RA were significantly lower in the AE group than in the cFS group; however, no significant differences in the levels of granzyme B, IFN-γ, IL-1ß, IL-4, IL-6, IL-8, and IL-10 were observed between the 2 groups. In addition, no significant differences in granzyme A, granzyme B, or cytokine levels were observed between acute encephalopathy patients with and those without neurologic sequelae. CONCLUSIONS: Our findings indicate the involvement of granzyme A in the pathogenesis of acute encephalopathy.

8.
J Prosthodont Res ; 64(3): 296-300, 2020 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-31554602

RESUMEN

PURPOSE: Maxillofacial prosthetic rehabilitation replaces missing structures to recover the function and aesthetics relating to facial defects or injuries. Deep learning is rapidly expanding with respect to applications in medical fields. In this study, we apply the artificial neural network (ANN)-based deep learning approach to coloration support for fabricating maxillofacial prostheses. METHODS: We compared two machine learning algorithms, ANN-based deep learning and the random forest algorithm, to determine the compounding amount of pigment. We prepared 52 silicone elastomer specimens of varying colors and measured the CIE 1976 L* a* b* color space information using a spectrophotometer on the input dataset. The output of these algorithms indicated the compounding amount of four pigments. According to the algorithms' pigment compounding predictions, we prepared the specimens for validation analysis and measured the CIE 1976 L* a* b* values. We determined the color differences between the real skin color of five research participants (22.3 ± 1.7 years) and that of the silicone elastomer specimens fabricated based on the algorithm predictions using the CIEDE00 ΔE00 color system. RESULTS: The color differences (ΔE00 value) between the real skin color and silicone elastomer validation specimens were 3.45 ± 0.87 (ANN) and 5.54 ± 1.41 (random forest), which indicates that the deep ANN approach produced superior results with respect to the ΔE00 value compared with the random forest algorithm. CONCLUSIONS: These results suggest that applying deep ANN is a promising technique for the coloration of maxillofacial prostheses.


Asunto(s)
Prótesis Maxilofacial , Coloración de Prótesis , Color , Ensayo de Materiales , Redes Neurales de la Computación , Elastómeros de Silicona
9.
Pediatr Int ; 61(12): 1188-1195, 2019 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-31560147

RESUMEN

BACKGROUND: Over 20 kinds of steroids, tacrolimus ointments, and cyclosporine capsules are usually recommended for the treatment of atopic dermatitis (AD), depending on the symptoms of patients. However, several side effects sometimes occur with the extensive use of these agents for the treatment of pediatric AD patients. The purpose of this study was to explore whether vitamin K2 could be a new immunosuppressive candidate for pediatric patients with AD. METHODS: The immunosuppressive efficacy of vitamin K2 was evaluated through a cell-culture procedure using mitogen-activated peripheral blood mononuclear cells (PBMCs) obtained from pediatric AD patients. RESULTS: The mean (SD) IC50 value of vitamin K2 for the proliferation of concanavalin A-activated PBMCs was 15.37 (30.05) µmol/L, while the value for tacrolimus was 0.10 (0.28) ng/mL (0.12 (0.35) nmol/L). There was a significant correlation between the IC50 values for vitamin K2 and those for tacrolimus (P = 0.0001, r = 0.8871). However, there was no significant correlation between the IC50 values of vitamin K2 and those of cyclosporine A or methylprednisolone. A significant correlation between the IC50 values of vitamin K2 or tacrolimus and blood eosinophil counts (P = 0.0099, r = 0.7086 and P = 0.0032, r = 0.7722, respectively) was observed. CONCLUSION: Vitamin K2 -inhibited T-cell mitogen stimulated proliferation of PBMCs from pediatric AD patients in a dose-dependent manner. The PBMCs from pediatric AD patients were more sensitive to the immunosuppressive efficacy of vitamin K2 than the PBMCs from healthy subjects. The individual immunosuppressive pharmacological efficacy of vitamin K2 and of tacrolimus could be inferred from the blood eosinophil count of pediatric AD patients.


Asunto(s)
Dermatitis Atópica/tratamiento farmacológico , Inmunosupresores/administración & dosificación , Vitamina K 2/administración & dosificación , Adulto , Proliferación Celular/efectos de los fármacos , Células Cultivadas , Niño , Preescolar , Ciclosporina/farmacología , Femenino , Voluntarios Sanos , Humanos , Inmunosupresores/farmacología , Leucocitos Mononucleares/efectos de los fármacos , Masculino , Metilprednisolona/farmacología , Tacrolimus/farmacología , Vitamina K 2/farmacología , Vitamina K 2/uso terapéutico
10.
Hum Genet ; 138(6): 661-672, 2019 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-31069507

RESUMEN

Tandem repeats (TRs) are widespread in the genomes of all living organisms. In eukaryotes, they are found in both coding and noncoding regions and have potential roles in the regulation of cellular processes such as transcription, translation and in the modification of protein structure. Recent studies have highlighted TRs as a key regulator of gene expression and a potential contributor to human evolution. Thus, TRs are emerging as an important source of variation that can result in differential gene expression at intra- and inter-species levels. In this study, we performed a genome-wide survey to identify TRs that have emerged in the human lineage. We further examined these loci to explore their potential functional significance for human evolution. We identified 152 human-specific TR (HSTR) loci containing a repeat unit of more than ten bases, with most of them showing a repeat count of two. Gene set enrichment analysis showed that HSTR-associated genes were associated with biological functions in brain development and synapse function. In addition, we compared gene expression of human HSTR loci with orthologues from non-human primates (NHP) in seven different tissues. Strikingly, the expression level of HSTR-associated genes in brain tissues was significantly higher in human than in NHP. These results suggest the possibility that de novo emergence of TRs could have resulted in altered gene expression in humans within a short-time frame and contributed to the rapid evolution of human brain function.


Asunto(s)
Encéfalo/metabolismo , Regulación de la Expresión Génica , Especificidad de Órganos/genética , Secuencias Repetidas en Tándem/genética , Animales , Secuencia de Bases , Evolución Molecular , Genoma Humano/genética , Humanos , Tasa de Mutación , Primates/genética , Homología de Secuencia de Ácido Nucleico
11.
Org Lett ; 20(23): 7461-7465, 2018 12 07.
Artículo en Inglés | MEDLINE | ID: mdl-30457332

RESUMEN

It has been established that a cationic rhodium(I)/( R)-tol-BINAP or ( R)-BINAP complex catalyzes the enantioselective [2 + 2 + 1] cycloaddition of 1,6-enynes, possessing monosubstituted alkene units, with cyclopropylideneacetamides at room temperature through the elimination of ethylene to give bicyclic (cyclopent-2-en-1-ylidene)acetamides with high enantioselectivity.

12.
Epigenetics Chromatin ; 11(1): 55, 2018 09 29.
Artículo en Inglés | MEDLINE | ID: mdl-30268152

RESUMEN

BACKGROUND: Genomic imprinting leads to maternal expression of IGF2R in both mouse and opossum. In mouse, the antisense long noncoding (lnc) RNA Airn, which is paternally expressed from the differentially methylated region (DMR) in the second intron of Igf2r, is required to silence the paternal Igf2r. In opossum, however, intriguingly, the DMR was reported to be in a different downstream intron (intron 11) and there was no antisense lncRNA detected in previous analyses. Therefore, clarifying the imprinting mechanism of marsupial IGF2R is of great relevance for understanding the origin and evolution of genomic imprinting in the IGF2R locus. Thus, the antisense lncRNA associated with the marsupial DMR can be considered as the 'missing link'. In this study, we identified a novel antisense lncRNA, ALID, after detailed analysis of the IGF2R locus in an Australian marsupial, the tammar wallaby, Macropus eugenii, and compared it to that of the grey short-tailed opossum, Monodelphis domestica. RESULTS: Tammar IGF2R showed maternal expression and had a maternally methylated CpG island (CGI) in intron 12 as well as a promoter CGI without differential methylation, but none in the second intron. Re-analysis of the IGF2R of opossum detected the CGI in intron 12, not intron 11, as previously reported, confirming that the DMR in intron 12 is conserved between these marsupials and so is the putative imprinting control region of marsupial IGF2R. ALID is paternally expressed from the middle of the DMR and is approximately 650 bp long with a single exon structure that is extremely short compared to Airn. Hence, the lncRNA transcriptional overlap of the IGF2R promoter, which is essential for the Igf2r silencing in the mouse, is likely absent in tammar. This suggests that fundamental differences in the lncRNA-based silencing mechanisms evolved in eutherian and marsupial IGF2R and may reflect the lack of differential methylation in the promoter CGI of marsupial IGF2R. CONCLUSIONS: Our study thus provides the best candidate factor for establishing paternal silencing of marsupial IGF2R without transcriptional overlap, which is distinct from the Igf2r silencing mechanism of Airn, but which may be analogous to the mode of action for the flanking Slc22a2 and Slc22a3 gene silencing in the mouse placenta.


Asunto(s)
Impresión Genómica , Marsupiales/genética , ARN sin Sentido/genética , ARN Largo no Codificante/genética , Animales , Metilación de ADN
13.
Biochem Biophys Res Commun ; 503(3): 1478-1483, 2018 09 10.
Artículo en Inglés | MEDLINE | ID: mdl-30029879

RESUMEN

The evolutionary conserved genomic sequences that have acquired significantly increased number of nucleotide substitutions specifically in the human lineage, called human accelerated regions (HARs), have been identified as candidate genomic regions that have contributed to the evolution of human-specific traits. A number of HARs were indeed shown to have novel enhancer activity and be associated with human-specific brain development and with cognition and social behavior. It is therefore of great importance to investigate the details of genomic function of each HAR to understand the roles of HARs as critical contributors to the genetic basis of human evolution. In this study, we identified a previously unannotated brain-expressed noncoding RNA gene, HSTR1, at a human-specific tandem repeat locus. Notably, the 5' flanking sequence of HSTR1 showed the signature of HARs and the dramatic human-specific enhancement of promoter activity, providing the evidence of positive selection to increase the expression level of HSTR1 during human evolution. We also revealed that the tandem repeat number in HSTR1 was highly variable among individual alleles and affected the stability of HSTR1 RNA, suggesting variation in the activity of HSTR1 between human individuals. Our work thus provides a novel candidate gene that potentially contributed to the evolution of the human brain. It may also underpin some of the variation between human brains.


Asunto(s)
Encéfalo/metabolismo , Repeticiones de Minisatélite/genética , ARN no Traducido/metabolismo , Humanos , ARN no Traducido/genética
14.
Sensors (Basel) ; 18(6)2018 May 24.
Artículo en Inglés | MEDLINE | ID: mdl-29882936

RESUMEN

We developed a multiband imaging CMOS image sensor (CIS) with a multi-storied photodiode structure, which comprises two photodiode (PD) arrays that capture two different images, visible red, green, and blue (RGB) and near infrared (NIR) images at the same time. The sensor enables us to capture a wide variety of multiband images which is not limited to conventional visible RGB images taken with a Bayer filter or to invisible NIR images. Its wiring layers between two PD arrays can have an optically optimized effect by modifying its material and thickness on the bottom PD array. The incident light angle on the bottom PD depends on the thickness and structure of the wiring and bonding layer, and the structure can act as an optical filter. Its wide-range sensitivity and optimized optical filtering structure enable us to create the images of specific bands of light waves in addition to visible RGB images without designated pixels for IR among same pixel arrays without additional optical components. Our sensor will push the envelope of capturing a wide variety of multiband images.

15.
Exp Dermatol ; 27(9): 1058-1060, 2018 09.
Artículo en Inglés | MEDLINE | ID: mdl-29697859

RESUMEN

We estimated the pharmacological efficacy of vitamin K1 (VK1 ) and VK2 on the mitogen-activated peripheral blood mononuclear cells (PBMCs) of paediatric atopic dermatitis (AD) patients. VK2 suppressed the in vitro proliferation of T-cell mitogen-activated PBMCs of AD patients. In contrast, VK1 had little effect on the PBMC proliferation. The IL-2 production from the activated PBMCs of AD patients significantly increased (P < .05), while the production significantly decreased by 100 µmol L-1 VK2 (P < .01). In addition, 100 µmol L-1 VK2 reduced the percentage of CD4+ and CD4+CD25+ cells in PBMCs. These results suggest that VK2 can modulate T-cell function in PBMCs of AD patients.


Asunto(s)
Dermatitis Atópica/sangre , Leucocitos Mononucleares/fisiología , Vitamina K 1/farmacología , Vitamina K 2/farmacología , Vitaminas/farmacología , Recuento de Linfocito CD4 , Proliferación Celular/efectos de los fármacos , Células Cultivadas , Niño , Concanavalina A/farmacología , Dermatitis Atópica/inmunología , Dermatitis Atópica/patología , Humanos , Interleucina-10/metabolismo , Interleucina-2/metabolismo , Mitógenos/farmacología , Linfocitos T Reguladores/patología
16.
Gen Comp Endocrinol ; 249: 1-14, 2017 08 01.
Artículo en Inglés | MEDLINE | ID: mdl-28242306

RESUMEN

Transthyretin (TTR) is a vertebrate-specific protein involved in thyroid hormone distribution in plasma, and its gene is thought to have emerged by gene duplication from the gene for the ancient TTR-related protein, 5-hydroxyisourate hydrolase, at some early stage of chordate evolution. We investigated the molecular and hormone-binding properties of the brown hagfish Paramyxine atami TTR. The amino acid sequence deduced from the cloned hagfish TTR cDNA shared 33-50% identities with those of other vertebrate TTRs but less than 24% identities with those of vertebrate and deuterostome invertebrate 5-hydroxyisourate hydrolases. Hagfish TTR, as well as lamprey and little skate TTRs, had an N-terminal histidine-rich segment, allowing purification by metal-affinity chromatography. The affinity of hagfish TTR for 3,3',5-triiodo-L-thyronine (T3) was 190 times higher than that for L-thyroxine, with a dissociation constant of 1.5-3.9nM at 4°C. The high-affinity binding sites were strongly sensitive to metal ions. Zn2+ and Cu2+ decreased the dissociation constant to one-order of magnitude, whereas a chelator, o-phenanthroline, increased it four times. The number of metal ions (mainly Zn2+ and Cu2+) was approximately 12/TTR (mol/mol). TTR was also a major T3-binding protein in adult hagfish sera and its serum concentration was approximately 8µM. These results suggest that metal ions and the acquisition of N-terminal histidine-rich segment may cooperatively contribute to the evolution toward an ancient TTR with high T3 binding activity from either 5-hydroxyisourate hydrolase after gene duplication.


Asunto(s)
Anguila Babosa/metabolismo , Metales/farmacología , Prealbúmina/metabolismo , Hormonas Tiroideas/metabolismo , Amidohidrolasas/metabolismo , Secuencia de Aminoácidos , Animales , Cationes Bivalentes/farmacología , ADN Complementario/genética , Perfilación de la Expresión Génica , Hidrólisis , Cinética , Filogenia , Prealbúmina/química , Prealbúmina/genética , Prealbúmina/aislamiento & purificación , Unión Proteica/efectos de los fármacos , ARN Mensajero/genética , ARN Mensajero/metabolismo , Proteínas Recombinantes/metabolismo , Suero/metabolismo , Factores de Tiempo , Triyodotironina/metabolismo , Ácido Úrico/análogos & derivados , Ácido Úrico/metabolismo
17.
J Air Waste Manag Assoc ; 67(8): 873-880, 2017 08.
Artículo en Inglés | MEDLINE | ID: mdl-28278030

RESUMEN

Particulate matter from a diesel engine, including soot and carbon nanomaterials, was collected on a sampling holder and the structure of the materials was studied by transmission electron microscopy (TEM) and scanning electron microscopy (SEM). As a result of employing gas oil/ethanol mixing fuel with sulfur and ferrocene/molybdenum as catalyst sources, formation of carbon nanotubes (CNT)-like materials in addition to soot was observed in the exhaust gas from a diesel engine. It was revealed that CNT-like materials were included among soot in our system only when the following three conditions were satisfied simultaneously: high ethanol fraction in fuel, high sulfur loading, and presence of catalyst sources in fuel. This study confirmed that if at least one of these three conditions was not satisfied, CNT-like materials were not observed in the exhaust from a diesel engine. These experimental results shown in this work provide insights into understanding CNT-like material formation mechanism in a diesel engine. IMPLICATIONS: Recent papers reported that carbon nanotube-like materials were included in the exhaust gas from engines, but conditions for carbon nanotube-like material formation have not been well studied. This work provides the required conditions for carbon nanotube-like material growth in a diesel engine, and this will be helpful for understanding the carbon nanotube-like material formation mechanism and taking countermeasures to preventing carbon nanotube-like material formation in a diesel engine.


Asunto(s)
Nanotubos de Carbono/análisis , Emisiones de Vehículos/análisis , Contaminantes Atmosféricos/análisis , Catálisis , Monitoreo del Ambiente , Etanol , Compuestos Ferrosos , Aceites Combustibles , Gasolina , Metalocenos , Microscopía Electrónica de Rastreo , Microscopía Electrónica de Transmisión , Molibdeno , Nanotubos de Carbono/ultraestructura , Hollín/análisis , Azufre
18.
Genome Biol Evol ; 8(8): 2288-96, 2016 08 16.
Artículo en Inglés | MEDLINE | ID: mdl-27389689

RESUMEN

The human genome contains thousands of retrocopies, mostly as processed pseudogenes, which were recently shown to be prevalently transcribed. In particular, those specifically acquired in the human lineage are able to modulate gene expression in a manner that contributed to the evolution of human-specific traits. Therefore, knowledge of the human-specific retrocopies that are transcribed or their full-length transcript structure contributes to better understand human genome evolution. In this study, we identified 16 human-specific retrocopies that harbor 5' CpG islands by in silico analysis and showed that 12 were transcribed in normal tissues and cancer cell lines with a variety of expression patterns, including cancer-specific expression. Determination of the structure of the transcripts associated with the retrocopies revealed that none were transcribed from their 5' CpG islands, but rather, from inside the 3' UTR and the nearby 5' flanking region of the retrocopies as well as the promoter of neighboring genes. The multiple forms of the transcripts, such as chimeric and individual transcripts in both the sense and antisense orientation, might have introduced novel post-transcriptional regulation into the genome during human evolution. These results shed light on the potential role of human-specific retrocopies in the evolution of gene regulation and genomic disorders.


Asunto(s)
ARN Mensajero/genética , Retroelementos , Regiones no Traducidas 3' , Línea Celular Tumoral , Islas de CpG , Regulación Neoplásica de la Expresión Génica , Humanos , Regiones Promotoras Genéticas , Transcripción Reversa
19.
Cell Biosci ; 6: 19, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-26981232

RESUMEN

BACKGROUND: Exposure of the American bullfrog Lithobates catesbeianus tadpoles to low temperature affects many biological processes including lipid metabolism and the thyroid hormone (TH) signaling pathway, resulting in arrest of TH-induced metamorphosis. To clarify what molecular events occur in this phenomenon, we investigated the glycerophospholipid and fatty acid (FA) compositions, the activities of mitochondrial enzymes and the transcript levels of related genes in the liver of control (26 °C) and cold-treated (4 °C) tadpoles with or without 5 nM 3,3',5-triiodothyronine (T3). RESULTS: Exposure to T3 decreased the tail height and polyunsaturation of FAs in the glycerophospholipids, and increased plasma glucose levels and transcript levels of primary TH-response genes including TH receptor, and some energy metabolic (cox4, srebp1 and fas) and FA chain elongase genes (elovl3 and elovl5). However, these T3-induced responses were abolished at 4 °C. Exposure to cold temperature enhanced plasma glucose, triglyceride and free FA levels, monounsaturation of FAs, mitochondrial enzymes activities (cytochrome c oxidase and carnitine palmitoyltransferase; U/g liver), with the upregulation of the genes involved in glycogenolysis (pygl), gluconeogenesis (pck1 and g6pc2), FA ß-oxidation (acadl), and cholesterol uptake and synthesis (hmgcr, srebp2 and ldlr1), glycerophospholipids synthesis (pcyt1, pcyt2, pemt, and pparg), and FA monounsaturation (scd1) and chain elongation (elovl1 and elovl2). T3 had little effect on the cold-induced changes. CONCLUSIONS: Our study demonstrated that exposures to T3 and cold temperature exert different effects on lipid metabolism, resulting in changes in the FA composition in glycerophospholipids, and suggests that a cold-induced signal may block TH-signaling pathway around primary TH-response genes.

20.
Biochem J ; 473(4): 449-61, 2016 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-26614767

RESUMEN

FABPs (fatty-acid-binding proteins) are a family of low-molecular-mass intracellular lipid-binding proteins consisting of ten isoforms. FABPs are involved in binding and storing hydrophobic ligands such as long-chain fatty acids, as well as transporting these ligands to the appropriate compartments in the cell. FABP5 is overexpressed in multiple types of tumours. Furthermore, up-regulation of FABP5 is strongly associated with poor survival in triple-negative breast cancer. However, the mechanisms underlying the specific up-regulation of the FABP5 gene in these cancers remain poorly characterized. In the present study, we determined that FABP5 has a typical CpG island around its promoter region. The DNA methylation status of the CpG island in the FABP5 promoter of benign prostate cells (PNT2), prostate cancer cells (PC-3, DU-145, 22Rv1 and LNCaP) and human normal or tumour tissue was assessed by bisulfite sequencing analysis, and then confirmed by COBRA (combined bisulfite restriction analysis) and qAMP (quantitative analysis of DNA methylation using real-time PCR). These results demonstrated that overexpression of FABP5 in prostate cancer cells can be attributed to hypomethylation of the CpG island in its promoter region, along with up-regulation of the direct trans-acting factors Sp1 (specificity protein 1) and c-Myc. Together, these mechanisms result in the transcriptional activation of FABP5 expression during human prostate carcinogenesis. Importantly, silencing of Sp1, c-Myc or FABP5 expression led to a significant decrease in cell proliferation, indicating that up-regulation of FABP5 expression by Sp1 and c-Myc is critical for the proliferation of prostate cancer cells.


Asunto(s)
Epigénesis Genética , Proteínas de Unión a Ácidos Grasos/genética , Regulación Neoplásica de la Expresión Génica , Neoplasias de la Próstata/genética , Línea Celular Tumoral , Metilación de ADN , Humanos , Masculino , Persona de Mediana Edad , Regiones Promotoras Genéticas , Proteínas Proto-Oncogénicas c-myc/metabolismo , Factor de Transcripción Sp1/metabolismo
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