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1.
Cell Biochem Biophys ; 79(2): 321-336, 2021 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-33559812

RESUMEN

Mesenchymal stem cell (MSC) transplantation is an effective periodontal regenerative therapy. MSCs are multipotent, have self-renewal ability, and can differentiate into periodontal cells. However, senescence is inevitable for MSCs. In vitro, cell senescence can be induced by long-term culture with/without cell passage. However, the regulatory mechanism of MSC senescence remains unclear. Undifferentiated MSC-specific transcription factors can regulate MSC function. Herein, we identified the regulatory transcription factors involved in MSC senescence and elucidated their mechanisms of action. We cultured human MSCs (hMSCs) with repetitive cell passages to induce cell senescence and evaluated the mRNA and protein expression of cell senescence-related genes. Additionally, we silenced the cell senescence-induced transcription factors, GATA binding protein 6 (GATA6) and SRY-box 11 (SOX11), and investigated senescence-related signaling pathways. With repeated passages, the number of senescent cells increased, while the cell proliferation capacity decreased; GATA6 mRNA expression was upregulated and that of SOX11 was downregulated. Repetitive cell passages decreased Wnt and bone morphogenetic protein (BMP) signaling pathway-related gene expression. Silencing of GATA6 and SOX11 regulated Wnt and BMP signaling pathway-related genes and affected cell senescence-related genes; moreover, SOX11 silencing regulated GATA6 expression. Hence, we identified them as pair of regulatory transcription factors for cell senescence in hMSCs via the Wnt and BMP signaling pathways.


Asunto(s)
Senescencia Celular/genética , Células de la Médula Ósea/citología , Proteínas Morfogenéticas Óseas/genética , Proteínas Morfogenéticas Óseas/metabolismo , Diferenciación Celular , Proliferación Celular , Células Cultivadas , Factor de Transcripción GATA6/antagonistas & inhibidores , Factor de Transcripción GATA6/genética , Factor de Transcripción GATA6/metabolismo , Histona Desacetilasa 2/genética , Histona Desacetilasa 2/metabolismo , Humanos , Células Madre Mesenquimatosas/citología , Células Madre Mesenquimatosas/metabolismo , Interferencia de ARN , ARN Interferente Pequeño/metabolismo , Factores de Transcripción SOXC/antagonistas & inhibidores , Factores de Transcripción SOXC/genética , Factores de Transcripción SOXC/metabolismo , Transducción de Señal/genética , Proteínas Wnt/genética , Proteínas Wnt/metabolismo
2.
Eur Cell Mater ; 41: 31-39, 2021 01 05.
Artículo en Inglés | MEDLINE | ID: mdl-33400815

RESUMEN

Bioactive glasses (BAG) are used as bone-graft substitutes in orthopaedic surgery. A specific BAG scaffold was developed by sintering BAG-S53P4 granules. It is hypothesised that this scaffold can be used as a bone substitute to fill bone defects and induce a bioactive membrane (IM) around the defect site. Beyond providing the scaffold increased mechanical strength, that the initial inflammatory reaction and subsequent IM formation can be enhanced by coating the scaffolds with poly(DL-lactide-co-glycolide) (PLGA) is also hypothesised. To study the immunomodulatory effects, BAG-S53P4 (± PLGA) scaffolds were placed on monolayers of primary human macrophage cultures and the production of various pro- and anti-inflammatory cytokines was assessed using reverse transcriptase quantitative polymerase chain reaction (RT-qPCR) and ELISA. To study the osteogenic effects, BAG-S53P4 (± PLGA) scaffolds were cultured with rabbit mesenchymal stem cells and osteogenic differentiation was evaluated by RT-qPCR and matrix mineralisation assays. The scaffold ion release was quantified and the BAG surface reactivity visualised. Furthermore, the pH of culture media was measured. BAG-S53P4 scaffolds had both anti-inflammatory and osteogenic properties that were likely attributable to alkalinisation of the media and ion release from the scaffold. pH change, ion release, and immunomodulatory properties of the scaffold could be modulated by the PLGA coating. Contrary to the hypothesis, the coating functioned by attenuating the BAG surface reactions and subsequent anti-inflammatory properties, rather than inducing an elevated inflammatory response compared to BAG-S53P4 alone. These results further validated the use of BAG-S53P4 (± PLGA) scaffolds as bone substitutes and indicate that scaffold properties can be tailored to a specific clinical need.


Asunto(s)
Sustitutos de Huesos , Células Madre Mesenquimatosas , Osteonecrosis , Animales , Tratamiento Basado en Trasplante de Células y Tejidos , Osteogénesis , Conejos , Andamios del Tejido
3.
Curr HIV Res ; 18(6): 475-479, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32753017

RESUMEN

BACKGROUND: Dental professionals have so many opportunities to use injection needles and sharp instruments during dental treatment that they face an increased risk of needlestick injuries. This retrospective study reports the utilization and clinical outcomes of occupational post-exposure prophylaxis (PEP) with anti-retroviral agents after being potentially exposed to HIV at the dental departments of Hiroshima University Hospital. OBJECTIVE: This study reports the utilization and clinical outcomes of occupational post-exposure prophylaxis (PEP) with antiretroviral agents after being potentially exposed to HIV at dental departments of Hiroshima University Hospital. METHODS: Data on the clinical status of HIV-infected source patients and information on HIV-exposed dental professionals from 2007 to 2018 were collected. RESULTS: Five dentists with an average experience of 5.6 years (1-15 years) were exposed. The averaged CD4-positive cell number and HIV-RNA load were 1176 (768-1898) /µl and less than 20 copies/ml, respectively, in all the patients. Two of the five HIV exposed dentists received PEP. Three months after the exposures, all of their results were negative in HIV antibody/antigen tests. CONCLUSION: ; These data might support the concept of "undetectable equals untransmittable", although HIV exposure in this study was not through sexual transmission.


Asunto(s)
Fármacos Anti-VIH/uso terapéutico , Antirretrovirales/uso terapéutico , Infecciones por VIH/tratamiento farmacológico , Lesiones por Pinchazo de Aguja/tratamiento farmacológico , Exposición Profesional/prevención & control , Profilaxis Posexposición/métodos , Adulto , Clínicas Odontológicas/estadística & datos numéricos , Odontólogos/estadística & datos numéricos , Femenino , Hospitales Universitarios/estadística & datos numéricos , Humanos , Japón , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Factores de Riesgo
4.
Science ; 368(6491): 654-659, 2020 05 08.
Artículo en Inglés | MEDLINE | ID: mdl-32381723

RESUMEN

The near-Earth asteroid (162173) Ryugu is thought to be a primitive carbonaceous object that contains hydrated minerals and organic molecules. We report sample collection from Ryugu's surface by the Hayabusa2 spacecraft on 21 February 2019. Touchdown images and global observations of surface colors are used to investigate the stratigraphy of the surface around the sample location and across Ryugu. Latitudinal color variations suggest the reddening of exposed surface material by solar heating and/or space weathering. Immediately after touchdown, Hayabusa2's thrusters disturbed dark, fine grains that originate from the redder materials. The stratigraphic relationship between identified craters and the redder material indicates that surface reddening occurred over a short period of time. We suggest that Ryugu previously experienced an orbital excursion near the Sun.

6.
AIDS Care ; 32(7): 829-834, 2020 07.
Artículo en Inglés | MEDLINE | ID: mdl-31426660

RESUMEN

The aim of the study was to evaluate the oral environment and the taste function of Japanese HIV-infected patients treated with antiretroviral therapy. Their median age of 73 patients taking anti-HIV drugs was 46 years. The median period of taking anti-HIV drugs was 30 months. The oral condition was evaluated by measurement of oral moisture, amount of saliva secretion, the number of oral bacteria, presence of oral candida, a taste test, and the number of missing teeth. The levels of oral moisture and secreted saliva were significantly lower in the HIV-infected group than in the healthy volunteer (control) group. The HIV-infected group showed a more robust decrease in taste sensation than the control group. The number of missing teeth was significantly higher in the HIV-infected group than in the control group. Furthermore, all of the evaluated oral conditions were worse in the HIV-infected patients whose CD4+ T lymphocyte counts were less than 500/mm3 than in the control group. It became clear that the patients taking anti-HIV drugs, especially the CD4+ count < 500/mm3 group, had a deteriorated oral environment and dysgeusia, suggesting that the management of oral hygiene is necessary to maintain oral health, which leads to systemic health.


Asunto(s)
Infecciones por VIH , Gusto , Terapia Antirretroviral Altamente Activa , Recuento de Linfocito CD4 , Infecciones por VIH/tratamiento farmacológico , Humanos , Japón/epidemiología , Persona de Mediana Edad
7.
Science ; 364(6437): 272-275, 2019 04 19.
Artículo en Inglés | MEDLINE | ID: mdl-30890589

RESUMEN

The near-Earth asteroid 162173 Ryugu, the target of the Hayabusa2 sample-return mission, is thought to be a primitive carbonaceous object. We report reflectance spectra of Ryugu's surface acquired with the Near-Infrared Spectrometer (NIRS3) on Hayabusa2, to provide direct measurements of the surface composition and geological context for the returned samples. A weak, narrow absorption feature centered at 2.72 micrometers was detected across the entire observed surface, indicating that hydroxyl (OH)-bearing minerals are ubiquitous there. The intensity of the OH feature and low albedo are similar to thermally and/or shock-metamorphosed carbonaceous chondrite meteorites. There are few variations in the OH-band position, which is consistent with Ryugu being a compositionally homogeneous rubble-pile object generated from impact fragments of an undifferentiated aqueously altered parent body.

8.
Artículo en Inglés | MEDLINE | ID: mdl-29956665

RESUMEN

BACKGROUND: Cough is a common feature of asthma, which is often resistant to inhaled corticosteroids (ICSs). The pathophysiology of this refractoriness may differ between daytime and nighttime asthmatic cough. We sought to identify factors contributing to ICS-refractory daytime and nighttime asthmatic cough. METHODS: Sixty-seven patients with asthma presenting solely or predominantly with chronic cough were prospectively enrolled from April 2012 to December 2014. At baseline and 12 weeks after ICS treatment, the capsaicin cough threshold (C2, C5) and methacholine airway sensitivity and reactivity were examined. A visual analog scale (VAS) and numeric scores were used to evaluate daytime and nighttime cough symptoms separately. The Japanese version of the Leicester Cough Questionnaire was also completed. When either the VAS or numeric scores showed an improvement of ≥50% or ≥2 points, patients were considered responders to ICS treatment. RESULTS: Fifty-five patients were eligible for evaluation. Subjective cough indices improved significantly at 12 weeks after ICS treatment (P<.001). Multivariate analysis revealed that lower C2 significantly contributed to residual daytime cough (P=.04). Meanwhile, methacholine hyperreactivity and lower IgE levels were predictors of the nighttime residual cough (P=.002 and P=.03, respectively). CONCLUSIONS: Heightened cough reflex sensitivity is an independent factor of daytime asthmatic cough that is refractory to ICSs. In contrast, airway hyperreactivity and less atopic status contribute to ICS-refractory nighttime cough.


Asunto(s)
Asma/complicaciones , Tos/etiología , Administración por Inhalación , Corticoesteroides/uso terapéutico , Adulto , Anciano , Antiasmáticos/uso terapéutico , Asma/tratamiento farmacológico , Tos/tratamiento farmacológico , Resistencia a Medicamentos , Femenino , Humanos , Masculino , Persona de Mediana Edad , Factores de Riesgo , Índice de Severidad de la Enfermedad , Factores de Tiempo
9.
J. investig. allergol. clin. immunol ; 29(1): 30-39, 2019. tab, graf
Artículo en Inglés | IBECS | ID: ibc-183961

RESUMEN

Background: Cough is a common feature of asthma, which is often resistant to inhaled corticosteroids (ICSs). The pathophysiology of this refractoriness may differ between daytime and nighttime asthmatic cough. We sought to identify factors contributing to ICS-refractory daytime and nighttime asthmatic cough. Methods: Sixty-seven patients with asthma presenting solely or predominantly with chronic cough were prospectively enrolled from April 2012 to December 2014. At baseline and 12 weeks after ICS treatment, the capsaicin cough threshold (C2, C5) and methacholine airway sensitivity and reactivity were examined. A visual analog scale (VAS) and numeric scores were used to evaluate daytime and nighttime cough symptoms separately. The Japanese version of the Leicester Cough Questionnaire was also completed. When either the VAS or numeric scores showed an improvement of ≥50% or ≥2 points, patients were considered responders to ICS treatment.Results: Fifty-five patients were eligible for evaluation. Subjective cough indices improved significantly at 12 weeks after ICS treatment (P<.001). Multivariate analysis revealed that lower C2 significantly contributed to residual daytime cough (P=.04). Meanwhile, methacholine hyperreactivity and lower IgE levels were predictors of the nighttime residual cough (P=.002 and P=.03, respectively). Conclusions: Heightened cough reflex sensitivity is an independent factor of daytime asthmatic cough that is refractory to ICSs. In contrast, airway hyperreactivity and less atopic status contribute to ICS-refractory nighttime cough


Introducción: La tos es una característica común del asma, que a menudo es resistente a los corticosteroides inhalados (ICS). La fisiopatología involucrada en dicha refractariedad al tratamiento esteroideo puede ser diferente entre la tos asmática diurna y nocturna. El objetivo del estudio es intentar identificar los factores que contribuyen a esta insensibilidad al tratamiento en la tos asmática diurna y nocturna. Métodos: Sesenta y siete pacientes, con asma solo o con tos crónica, se inscribieron prospectivamente desde abril de 2012 a diciembre de 2014. Al inicio del estudio y 12 semanas después del tratamiento con ICS, se examinaron el umbral de tos frente a capsaicina (C2, C5) y la sensibilidad y reactividad de las vías respiratorias a la metacolina. Se usaron escalas analógicas visuales (VAS) y puntajes numéricos para evaluar los síntomas de tos diurna y nocturna de forma separada. La versión japonesa del Leicester Cough Questionnaire también se completó. Cuando las VAS o los puntajes numéricos mostraron una mejoría de ≥50% o ≥2 puntos, los pacientes se consideraron respondedores al tratamiento con ICS. Resultados: Cincuenta y cinco pacientes completaron adecuadamente toda la evaluación. Los índices subjetivos de tos mejoraron significativamente a las 12 semanas después del tratamiento con ICS (p <0,001). El análisis multivariante reveló que una C2 más baja contribuía significativamente a la tos diurna residual (p = 0,04). Por otra parte, la hiperreactividad a la metacolina y los niveles más bajos de IgE fueron predictores de la tos residual nocturna (p = 0,002 y p = 0,03, respectivamente).Conclusiones: La sensibilidad aumentada a la tos es un factor independiente de la tos asmática diurna refractaria a los corticoides. Por el contrario, la hiperreactividad de las vías respiratorias y la ausencia de atopia contribuyen a la tos nocturna refractaria a los ICS


Asunto(s)
Humanos , Asma/tratamiento farmacológico , Tos/tratamiento farmacológico , Rinitis Alérgica/inmunología , Hipersensibilidad Inmediata/inmunología , Corticoesteroides/administración & dosificación , Administración por Inhalación , Pruebas de Función Respiratoria/estadística & datos numéricos , Tos/inmunología , Asma/inmunología
10.
Transplant Proc ; 50(10): 2986-2991, 2018 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-30577158

RESUMEN

BACKGROUND: The levels of corneal donation are insufficient to meet the demand for corneal transplantation in Japan. To overcome this problem, we started to routinely mention the possibility of corneal donation to the families of patients who died in our hospital's Urology Department in February 2008. In this study, we evaluated the effectiveness of this approach. METHODS: We retrospectively reviewed the medical records of the patients who died in the Department of Urology, St. Marianna University School of Medicine Hospital, and analyzed the patients' characteristics and information about corneal donation. RESULTS: In total, 211 patients died in our department between February 2008 and March 2017, and 155 patients were medically suitable corneal donors. We mentioned the possibility of corneal donation to 129 (83.2%) families, and 29 (18.7%) families agreed. Three families subsequently withdrew their consent. Finally, 26 (16.8%) of the families that were approached about corneal donation by urologists agreed to donate their relatives' corneas. Another 2 families voluntarily offered to donate their relatives' corneas. Thus, 28 (18.1%) of 155 medically suitable donors donated their corneas for transplantation. Twenty-six (92.8%) donors were 60 years or older and all donors were affected with malignant genitourinary tumors. Fifty-four (96.4%) corneas were successfully transplanted into recipients. CONCLUSIONS: Even elderly patients who die of solid carcinoma can be an important source of corneal donors. In this study, we showed that routine referral by urologists increased corneal donation. If this approach were adopted by other departments, it might further increase the number of corneal donations.


Asunto(s)
Trasplante de Córnea , Derivación y Consulta , Donantes de Tejidos/provisión & distribución , Obtención de Tejidos y Órganos/métodos , Trasplantes/provisión & distribución , Adulto , Anciano , Anciano de 80 o más Años , Femenino , Humanos , Japón , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Neoplasias Urológicas/mortalidad , Urólogos
11.
Transplant Proc ; 50(10): 3961-3963, 2018 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-30577296

RESUMEN

Page kidney refers to a clinical condition that is characterized by the acute onset of hypertension and renal dysfunction owing to external compression of the kidney by a hematoma, tumor, lymphocele, or urinoma. We report a case in which Page kidney occurred after a nonepisode protocol renal allograft biopsy. A 31-year-old man with end-stage renal disease received a living related kidney transplant from his father. One year later, a nonepisode protocol renal allograft biopsy was performed. A day later, the patient's serum creatinine level increased to 4.23 mg/dL, and a subcapsular renal hematoma was detected using ultrasonography and computed tomography. Page kidney was diagnosed, and immediate surgical removal of the hematoma was performed. Nine days after the operation, the patient's serum creatinine level had improved to 1.89 mg/dL. Page kidney is a serious but treatable complication of renal allograft biopsies, and clinicians should pay attention to such complications, even in the setting of nonepisode protocol renal allograft biopsies.


Asunto(s)
Aloinjertos/cirugía , Biopsia con Aguja Gruesa/efectos adversos , Hematoma/etiología , Trasplante de Riñón , Adulto , Humanos , Hipertensión/etiología , Riñón/patología , Masculino , Trasplante Homólogo/efectos adversos
12.
J Periodontal Res ; 53(5): 870-882, 2018 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-29900548

RESUMEN

OBJECTIVE AND BACKGROUND: Human periodontal ligament mesenchymal stem cells (hPDLMSCs) are reported to be responsible for homeostasis and regeneration of periodontal tissue. Although hPDLMSCs are commonly cultured in monolayers, monolayer cultures have been reported as inferior to 3-dimensional cultures such as spheroids, which are spherical clusters of cells formed by self-assembly. The aim of this study was to examine the osteogenic phenotype of spheroids of hPDLMSCs, compared with monolayer cultures of hPDLMSC, in vitro and in vivo. MATERIAL AND METHODS: Spheroids were formed using microwell chips that were tagged with polyethylene glycol. Mesenchymal stem cell (MSC) markers in hPDLMSC spheroids were examined by flow cytometer. Real-time polymerase chain reaction analysis was examined to measure the expressions of stemness markers and osteogenesis-related genes in monolayer and spheroid-cultured hPDLMSCs. Immunofluorescence analysis was performed to confirm protein expressions of stemness markers in PDLMSC spheroids. Nodule formation assay, alkaline phosphatase (ALP) activity assay and transplantation assay in a mouse calvarial defect model were performed to confirm the osteogenic potential of hPDLMSC spheroids. To elucidate the mechanism of spheroid culture enhanced osteogenesis in hPDLMSCs with osteoinductive medium (OIM), a small interfering RNA (siRNA) assay targeted with secreted frizzled-related protein 3 (SFRP3) was examined. The levels of SFRP3 expression in monolayer and spheroid-cultured hPDLMSCs with OIM were measured by real-time polymerase chain reaction and western blotting analysis. ALP gene expression and ALP activity were examined in SFRP3-deficient hPDLMSC spheroids. RESULTS: The hPDLMSC spheroids expressed MSC markers, which were similar to hPDLMSCs grown in monolayer cultures. Intriguingly, the protein and mRNA expressions of transcription factors that regulate "stemness" were significantly increased in hPDLMSC spheroids, compared with hPDLMSCs in monolayer cultures. Nodule formation by hPDLMSCs was significantly increased in spheroid cultures grown with OIM, compared with monolayer-cultured hPDLMSCs. ALP activity and expression of osteogenesis-related genes were also significantly enhanced in hPDLMSC spheroids, compared with monolayer cultures. Treatment with hPDLMSC spheroids significantly enhanced new bone formation in a murine calvarial defect model, compared with hPDLMSCs in monolayer culture. Finally, to elucidate mechanisms by which spheroid culture enhances ALP activation in hPDLMSCs grown with OIM, an siRNA assay was used to manipulate expression of SFRP3, a Wnt signaling antagonist. Knockdown of SFRP3 suppressed ALP gene expression in hPDLMSCs grown in OIM; further, it suppressed ALP activity in spheroid culture. These data suggest that the enhancement of osteogenic potential in hPDLMSC spheroids is regulated through SFRP3-mediated ALP activation. CONCLUSION: Spheroid cultures of hPDLMSCs may be a novel and useful tool in regenerative medicine.


Asunto(s)
Técnicas de Cultivo de Célula/métodos , Células Madre Mesenquimatosas/citología , Células Madre Mesenquimatosas/fisiología , Osteogénesis/fisiología , Ligamento Periodontal/citología , Esferoides Celulares , Fosfatasa Alcalina/genética , Fosfatasa Alcalina/metabolismo , Animales , Células Cultivadas , Medios de Cultivo , Expresión Génica , Péptidos y Proteínas de Señalización Intracelular/genética , Péptidos y Proteínas de Señalización Intracelular/metabolismo , Ratones , Osteogénesis/genética , Ligamento Periodontal/metabolismo , Transducción de Señal/fisiología
13.
J Colloid Interface Sci ; 528: 400-409, 2018 Oct 15.
Artículo en Inglés | MEDLINE | ID: mdl-29879617

RESUMEN

HYPOTHESIS: Some low molecular weight additives can strongly influence the phase behavior of aqueous surfactant systems, and this offers an important handle to control the properties of surfactant solutions and thus to optimize the stability and performance of various formulations. EXPERIMENTS: The surfactant dioctadecyldimethylammonium chloride (DODAC) self-assembles into two lamellar phases in water, the gel phase (Lß) and the liquid crystalline phase (Lα). Here, we present approaches to tune the gel-to-liquid crystalline transition temperature (Tm) with the use of additives. The effects of urea, sodium butyrate and butyric acid on the packing behavior of DODAC were determined. The surfactant phases were characterized using polarized optical microscopy (POM), differential scanning calorimetry (DSC), and small/wide angle X-ray scattering (SWAXS). FINDINGS: All three additives - urea, sodium butyrate and butyric acid yield a single and stable lamellar phase. Urea and sodium butyrate have only minor effects on Tm, butyric acid gives a large decrease as it stabilizes the Lα phase with respect to the Lß phase. From the bilayer thickness of the gel phase an interdigitated or tilted packing of the surfactant molecules is suggested. The addition of sodium butyrate gives a highly interdigitated gel structure and resulted in the transition from lamellar liquid crystal to an isotropic L3 phase.

14.
Phys Chem Chem Phys ; 20(7): 5217-5226, 2018 Feb 14.
Artículo en Inglés | MEDLINE | ID: mdl-29399688

RESUMEN

Thermal conductivities (TCs) of graphene (g)/hexagonal boron nitride (hBN) heterobilayers with interlayer sp3 bonds are computed using nonequilibrium molecular dynamics (NEMD) simulations. It is revealed that the TC of a g/hBN heterobilayer drastically decreases if there is even a few interlayer sp3 bonds, and continues to gradually decrease upon increasing their fraction up to 0.25, where the fraction of the interlayer sp3 bonds is defined by the atomic fraction of interlayer-sp3-bonded carbon atoms within graphene constituting a g/hBN heterobilayer. If their fraction exceeds 0.25, the TC of a g/hBN heterobilayer gradually increases, namely, the TC of a g/hBN heterobilayer takes a minimum at the fraction of 0.25 of the interlayer sp3 bonds. In order to understand such a behavior of the TC of the heterobilayer, the local phonon density of states (DOSs) in each of the two layers is calculated. By examining the local phonon DOSs, it was found that the existence of the minimum TC of the heterobilayer can be understood by considering both the phonon scattering and the characteristic change of the heterobilayer structure. In the range of the low fractions of interlayer sp3 bonds, the van der Waals (vdW) interactions are predominantly effective for binding the two layers, and the interlayer sp3 bonds act as phonon scatterers like defects to make the TC of the heterobilayer decrease. Upon increasing the fraction of interlayer sp3 bonds, the contribution of the interlayer sp3 bonds to the unification of the two layers becomes stronger, and hence the rigidity of the heterobilayer structure gradually increases. If their fraction exceeds 0.25, the heterobilayer structure approaches a quasi-three-dimensional one, so that the TC of the heterobilayer increases. These findings will be useful for tuning the TCs of g/hBN heterobilayers via interlayer sp3 bonds.

15.
Clin Exp Immunol ; 192(3): 325-336, 2018 06.
Artículo en Inglés | MEDLINE | ID: mdl-29393507

RESUMEN

RNA-binding proteins (RBPs) regulate mRNA stability by binding to the 3'-untranslated region (UTR) region of mRNA. Human antigen-R (HuR), one of the RBPs, is involved in the progression of diseases, such as rheumatoid arthritis, diabetes mellitus and some inflammatory diseases. Interleukin (IL)-6 is a major inflammatory cytokine regulated by HuR binding to mRNA. Periodontal disease (PD) is also an inflammatory disease caused by elevations in IL-6 following an infection by periodontopathogenic bacteria. The involvement of HuR in the progression of PD was assessed using in-vitro and in-vivo experiments. Immunohistochemistry of inflamed periodontal tissue showed strong staining of HuR in the epithelium and connective tissue. HuR mRNA and protein level was increased following stimulation with Porphyromonas gingivalis (Pg), one of the periodontopathogenic bacteria, lipopolysacchride (LPS)-derived from Pg (PgLPS) and tumour necrosis factor (TNF)-α in OBA-9, an immortalized human gingival epithelial cell. The luciferase activity of 3'-UTR of IL-6 mRNA was increased by TNF-α, Pg and PgLPS in OBA-9. Luciferase activity was also increased in HuR-over-expressing OBA-9 following a bacterial stimulation. Down-regulation of HuR by siRNA resulted in a decrease in mRNA expression and production of IL-6. In contrast, the over-expression of HuR increased IL-6 mRNA expression and production in OBA-9. The HuR inhibitor, quercetin, suppressed Pg-induced HuR mRNA expression and IL-6 production in OBA-9. An oral inoculation with quercetin also inhibited bone resorption in ligature-induced periodontitis model mice as a result of down-regulation of IL-6. These results show that HuR modulates inflammatory responses by regulating IL-6.


Asunto(s)
Proteína 1 Similar a ELAV/metabolismo , Encía/patología , Interleucina-6/genética , Periodontitis/patología , Regiones no Traducidas 3'/genética , Adulto , Anciano , Animales , Resorción Ósea/tratamiento farmacológico , Línea Celular , Proteína 1 Similar a ELAV/genética , Células Epiteliales/metabolismo , Femenino , Encía/citología , Humanos , Lipopolisacáridos/inmunología , Luciferasas/metabolismo , Masculino , Ratones , Ratones Endogámicos BALB C , Periodontitis/tratamiento farmacológico , Porphyromonas gingivalis/inmunología , Porphyromonas gingivalis/patogenicidad , Quercetina/farmacología , Interferencia de ARN , ARN Mensajero/genética , ARN Mensajero/metabolismo , ARN Interferente Pequeño/genética , Factor de Necrosis Tumoral alfa
16.
J Vet Pharmacol Ther ; 41(1): e30-e34, 2018 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-28752932

RESUMEN

In cynomolgus macaques (Macaca fascicularis), widely used in drug metabolism studies, CYP2C9, CYP2C76, CYP2D6, CYP3A4, and CYP3A5, important drug-metabolizing enzymes, are abundantly expressed in liver and metabolize cytochrome P450 substrates. CYP2C9 (c.334A>C), CYP2C76 (c.449TG>A), CYP2D6 (c.891A>G), CYP3A4 (IVS3 + 1G>del), and CYP3A5 (c.625A>T) substantially influence metabolic activity of enzymes, and thus are important variants in drug metabolism studies. In this study, a real-time PCR method was developed for genotyping these variants. The validity of the methods was verified by genotyping two wild type, two heterozygous, and two homozygous DNAs and was used to genotype 41 cynomolgus macaques (from Cambodia, Indonesia, the Philippines, or Vietnam) for the five variants, along with another important variant CYP2C19 (c.308C>T). The CYP2C9 and CYP2C19 variants were found only in Cambodian and Vietnamese animals, while the CYP2C76 and CYP2D6 variants were found only in Indonesian and Philippine animals. The CYP3A4 and CYP3A5 variants were not found in any of the animals analyzed. Mauritian animals, genotyped using next-generation sequencing data for comparison, possessed the CYP2C19 and CYP2D6 variants, but not the other variants. These results indicated differences in prevalence of these important variants among animal groups. Therefore, the genotyping tool developed is useful for drug metabolism studies using cynomolgus macaques.


Asunto(s)
Sistema Enzimático del Citocromo P-450/genética , Técnicas de Genotipaje/veterinaria , Macaca fascicularis/genética , Animales , Citocromo P-450 CYP2C9/genética , Citocromo P-450 CYP3A/genética , Femenino , Secuenciación de Nucleótidos de Alto Rendimiento/veterinaria , Masculino , Polimorfismo de Nucleótido Simple/genética , Reacción en Cadena en Tiempo Real de la Polimerasa/veterinaria
17.
Transplant Proc ; 49(10): 2388-2391, 2017 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-29198686

RESUMEN

In recent years, the frequency of high-risk kidney transplantations has increased. We report a case in which a 72-year-old man with various severe comorbidities (prostate cancer, diabetes mellitus, complete atrioventricular block, coronary artery stenosis, severe stenosis of the popliteal arteries, and severe calcification of the iliac arteries) who received an orthotopic kidney transplantation. To prevent the occurrence of acute limb ischemia due to the steal phenomenon (caused by the kidney graft), we decided that a heterotopic kidney transplantation involving the iliac arteries was not an appropriate option. Therefore, as an alternative, left native nephrectomy was performed followed by an orthotopic kidney transplantation to the native renal artery and renal vein through a left subcostal incision. Postoperative ureteral stenosis occurred, and so stent exchange was required every 6 months. Despite the ureteral complication, the patient's serum creatinine level was 1.5 mg/dL at 2 years after the procedure.


Asunto(s)
Nefropatías Diabéticas/cirugía , Trasplante de Riñón/métodos , Anciano , Bloqueo Atrioventricular/epidemiología , Enfermedades Cardiovasculares/epidemiología , Diabetes Mellitus/epidemiología , Nefropatías Diabéticas/epidemiología , Humanos , Masculino , Neoplasias de la Próstata/epidemiología
19.
Epidemiol Infect ; 145(8): 1557-1566, 2017 06.
Artículo en Inglés | MEDLINE | ID: mdl-28260536

RESUMEN

A nationwide study of Shiga toxin-producing Escherichia coli (STEC) was performed to determine the prevalence, characteristics and risk factors for fecal shedding of STEC among cattle in Japan. Information on rearing practices was also collected to identify risk factors for fecal shedding of STEC. STEC was isolated from 24·1% of samples (133/551) collected from 59·1% of farms (65/110). Bayesian clustering using the virulence marker profiles of the isolates subdivided the isolates into four genetically distinct groups, two of which corresponded to eae- or saa-positive STEC, which can cause severe disease in human. Both STEC groups exhibited characteristic phylogeny and virulence marker profiles. It is noteworthy that the tellurite resistance gene was not detected in all saa-positive STEC isolates, suggesting that the standard isolation method using tellurite might lead to an underestimation of the prevalence of saa-positive STEC. A multivariate logistic regression model using epidemiological information revealed a significantly (P < 0·01) high odds ratio on STEC fecal shedding in tie-stall housing and a low odds ratio in flat feed box and mechanical ventilation. Information on isolate characteristics of the two major pathotypes and risk factors in rearing practices will facilitate the development of preventative measures for STEC fecal shedding from cattle.


Asunto(s)
Enfermedades de los Bovinos/epidemiología , Enfermedades de los Bovinos/microbiología , Infecciones por Escherichia coli/veterinaria , Escherichia coli Shiga-Toxigénica/fisiología , Escherichia coli Shiga-Toxigénica/patogenicidad , Factores de Virulencia/aislamiento & purificación , Crianza de Animales Domésticos/normas , Animales , Derrame de Bacterias , Teorema de Bayes , Bovinos , Infecciones por Escherichia coli/epidemiología , Infecciones por Escherichia coli/microbiología , Heces/microbiología , Femenino , Japón/epidemiología , Masculino , Filogenia , Prevalencia , Factores de Riesgo , Escherichia coli Shiga-Toxigénica/genética
20.
Clin Exp Allergy ; 47(8): 998-1006, 2017 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-28326636

RESUMEN

BACKGROUND: Genetic markers of susceptibility to asthma exacerbations in adults remain unclear. OBJECTIVE: To identify genetic markers of asthma exacerbations, particularly in patients with type-2 inflammatory endotype. METHODS: In this observational study of patients enrolled in the Kinki Hokuriku Airway disease Conference multicenter study, frequency of exacerbations requiring systemic corticosteroids during 2 years after enrolment and associated risk factors was determined. For genetic marker analysis, interleukin-4 receptor α (IL4RA) rs8832 and a disintegrin and metalloprotease 33 (ADAM33) S_2 (rs528557), T_1 (rs2280091), T_2 (rs2280090), and V_4 (rs2787094) variants were included. Elevated serum periostin levels at enrolment (≥95 ng/mL, defined as type-2 inflammatory endotype) were considered in the analysis. RESULTS: Among 217 patients who were successfully followed up for 2 years after enrolment, 60 patients showed at least one asthma exacerbation during the 2 years. Airflow limitation (%FEV1 <80%) and recent exacerbations but not genetic variants were identified as risk markers of exacerbations. A total of 27 patients showed type-2 inflammatory endotype (serum periostin ≥95 ng/mL at enrolment) and subsequent exacerbations; risk factors in these patients were airflow limitation (odds ratio, 6.51; 95% confidence interval (CI): 2.37-18.6; P=.0003), GG genotype of IL4RA rs8832 (odds ratio, 4.01; 95% CI: 1.47-11.0; P=.007), and A allele of ADAM33 T_2 (odds ratio, 2.81; 95% CI: 1.05-7.67; P=.04) by multivariate analysis. In addition, GG genotype of IL4RA rs8832 was associated with type-2 endotype, whereas A allele of ADAM33 T_2 was associated with mixed type of eosinophilic/type-2 and neutrophilic inflammations. CONCLUSIONS AND CLINICAL RELEVANCE: IL4RA and ADAM33 variants may be risk markers of asthma exacerbations in type-2 inflammatory endotype. Precise endotyping may facilitate the identification of genetic risk markers of asthma exacerbations.


Asunto(s)
Proteínas ADAM , Asma/sangre , Asma/genética , Subunidad alfa del Receptor de Interleucina-4 , Proteínas ADAM/sangre , Proteínas ADAM/genética , Adulto , Anciano , Asma/tratamiento farmacológico , Estudios de Seguimiento , Marcadores Genéticos , Humanos , Subunidad alfa del Receptor de Interleucina-4/sangre , Subunidad alfa del Receptor de Interleucina-4/genética , Persona de Mediana Edad , Factores de Riesgo
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