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1.
Water Res ; 236: 119951, 2023 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-37060876

RESUMEN

Here, we examined the efficiencies of drinking water treatment processes for the removal and inactivation of human sapovirus (HuSaV). We applied a recently developed in vitro cell-culture system to produce purified solutions of HuSaV containing virus concentrations high enough to conduct virus-spiking experiments, to develop an integrated cell culture-polymerase chain reaction (ICC-PCR) assay to quantify the infectivity of HuSaV, and to conduct virus-spiking experiments. In virus-spiking coagulation-sedimentation-rapid sand filtration (CS-RSF) and coagulation-microfiltration (C-MF) experiments, HuSaV removals of 1.6-3.7-log10 and 1.2->4.3-log10, respectively, were observed. The removal ratios observed with CS-RSF were comparable and correlated with those of murine norovirus (MNV, a widely used surrogate for human noroviruses) and pepper mild mottle virus (PMMoV, a potential surrogate for human enteric viruses in physical and physicochemical drinking water treatment processes), and those observed with C-MF were higher than but still correlated with those of MNV and PMMoV, indicating that MNV and PMMoV are both potential surrogates for HuSaV in CS-RSF and C-MF. For astrovirus (AstV, a representative human enteric virus), removal ratios of 1.8-3.3-log10 and 1.1->4.0-log10 were observed with CS-RSF and C-MF, respectively. The removal ratios of AstV observed with CS-RSF were comparable and correlated with those of PMMoV, and those observed with C-MF were higher than but still correlated with those of PMMoV, indicating that PMMoV is a potential surrogate for AstV in CS-RSF and C-MF. When the efficacy of chlorine treatment was examined by using the developed ICC-PCR assay, 3.8-4.0-log10 inactivation of HuSaV was observed at a CT value (free-chlorine concentration [C] multiplied by contact time [T]) of 0.02 mg-Cl2·min/L. The infectivity reduction ratios of HuSaV were comparable with those of MNV. For AstV, 1.3-1.7-log10 and >3.4-log10 inactivation, as evaluated by ICC-PCR, was observed at CT values of 0.02 and 0.09 mg-Cl2·min/L, respectively. These results indicate that HuSaV and AstV are both highly sensitive to chlorine treatment and more sensitive than a chlorine-resistant virus, coxsackievirus B5 (1.3-log10 inactivation at a CT value of 0.4 mg-Cl2·min/L, as evaluated by the ICC-PCR assay).


Asunto(s)
Agua Potable , Enterovirus , Norovirus , Sapovirus , Virus , Humanos , Animales , Ratones , Cloro , Filtración/métodos
2.
Occup Med (Lond) ; 72(9): 598-603, 2022 12 31.
Artículo en Inglés | MEDLINE | ID: mdl-36516221

RESUMEN

BACKGROUND: Low back pain (LBP) and poor subjective sleep quality (SSQ) are major risk factors for presenteeism. However, no studies have investigated whether combined LBP and poor SSQ are associated with presenteeism. AIMS: We aimed to examine whether a combination of LBP and poor SSQ is associated with presenteeism. METHODS: This cross-sectional study included 936 workers (median age, 38 years; men, 89%), with evaluated presenteeism using the work limitations questionnaire. We divided them into 'no presenteeism' and 'presenteeism' categories. The presence of LBP was defined as a numerical rating scale (NRS) score of ≥1 in current pain intensity. SSQ was assessed using a single question regarding whether the participants typically got enough sleep. We categorized the participants into four groups: (i) LBP + poor SSQ, (ii) non-LBP + poor SSQ, (iii) LBP + good SSQ and (iv) non-LBP + good SSQ. Logistic regression analysis was used to investigate the association between presenteeism and the presence of LBP and poor SSQ, adjusting for age, sex, work type, education, marital status, smoking status, body mass index and weekly working hours. RESULTS: The data from 533 participants were used for analysis (median age, 38 years; men, 90%, response rate, 66%). Combined LBP and poor SSQ were significantly associated with presenteeism (non-LBP + poor SSQ: adjusted odds ratio = 0.56, 95% CI 0.32-0.96; LBP + good SSQ: 0.33, 0.20-0.56; non-LBP + good SSQ: 0.29, 0.18-0.48). CONCLUSIONS: Evaluating both LBP and SSQ may be beneficial in considering presenteeism.


Asunto(s)
Dolor de la Región Lumbar , Masculino , Humanos , Adulto , Dolor de la Región Lumbar/epidemiología , Dolor de la Región Lumbar/etiología , Calidad del Sueño , Estudios Transversales , Factores de Riesgo , Sueño , Encuestas y Cuestionarios
3.
Sci Adv ; 6(6): eaaz0611, 2020 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-32128385

RESUMEN

A nearly free electron metal and a Mott insulating state can be thought of as opposite ends of the spectrum of possibilities for the motion of electrons in a solid. Understanding their interaction lies at the heart of the correlated electron problem. In the magnetic oxide metal PdCrO2, nearly free and Mott-localized electrons exist in alternating layers, forming natural heterostructures. Using angle-resolved photoemission spectroscopy, quantitatively supported by a strong coupling analysis, we show that the coupling between these layers leads to an "intertwined" excitation that is a convolution of the charge spectrum of the metallic layer and the spin susceptibility of the Mott layer. Our findings establish PdCrO2 as a model system in which to probe Kondo lattice physics and also open new routes to use the a priori nonmagnetic probe of photoemission to gain insights into the spin susceptibility of correlated electron materials.

4.
Philos Trans A Math Phys Eng Sci ; 377(2154): 20180400, 2019 Sep 23.
Artículo en Inglés | MEDLINE | ID: mdl-31378174

RESUMEN

Spectroscopy of absorption lines of H3+ in the central molecular zone (CMZ) of the Galaxy show that a previously largely unknown component of the interstellar medium there, warm (T∼200 K) and diffuse (n ≲ 102 cm-3) gas, makes up a large fraction of the volume of the CMZ, and that this gas is moving radially outward from the centre. These discoveries upend the generally accepted understanding that the interstellar environment of the CMZ comprises almost entirely an ultra-hot plasma and dense molecular clouds. The radial momentum associated with the diffuse gas in the CMZ exceeds that of the ejecta of thousands of core-collapse supernovae and implies some extraordinary past activity in the centre, possibly associated with the supermassive black hole, Sgr A*. We speculate that within approximately 106 years, gravity could halt the expansion of the diffuse gas and that contraction towards the centre could then commence. This article is part of a discussion meeting issue 'Advances in hydrogen molecular ions: H3+, H5+ and beyond'.

6.
Haemophilia ; 24(5): e328-e337, 2018 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-29902361

RESUMEN

INTRODUCTION: Immune tolerance induction (ITI) was the primary therapeutic approach to eradicate inhibitors in haemophilia patients. Several large ITI registries had been reported, but successful predictors of ITI outcome are still debated. No reports are available on large ITI studies in non-caucasian countries. AIM: We designed a retrospective cohort study of ITI in Japanese haemophilia patients with inhibitor. METHODS: Retrospective data were collected from 155 haemophilia (H)A (140 severe-type) and 7 HB (7 severe-type) patients treated at 45 institutions. ITI outcome was centrally reviewed. We defined "success" as undetectable inhibitor after 2 consecutive measurements. RESULTS: The ITI success rate was 71.2% for HA and 83.3% for HB. Cumulated success rates for HA achieving 50% and 75% were 0.7 and 2 years after treatment, respectively. Significant successful predictors in HA were low-responding inhibitors compared to high-responding inhibitors, shorter time to the start of ITI, and lower historical and treatment peak titres of inhibitor. Dose regimen (high dose; ≥90 IU/kg every day, low dose; ≤75 IU/kg, 3 d/wk) and the type of therapeutic product did not affect outcomes. The success rate of salvage ITI using von Willebrand factor-containing factor VIII was 50% (n = 6/12), and patient age at the start of salvage ITI was a significant predictor. The inhibitor recurred in 6 HA cases (3.9%). CONCLUSION: The results provided potentially important information for improving future success rates for ITI in inhibitor patients.


Asunto(s)
Hemofilia A/inmunología , Tolerancia Inmunológica/inmunología , Preescolar , Estudios de Cohortes , Femenino , Hemofilia A/tratamiento farmacológico , Humanos , Japón , Masculino , Estudios Retrospectivos , Resultado del Tratamiento
8.
Orthop Traumatol Surg Res ; 104(2): 177-183, 2018 04.
Artículo en Inglés | MEDLINE | ID: mdl-29274859

RESUMEN

BACKGROUND: Rotational allowance at the tibiofemoral joint would be required during deep flexion. However, the amount of flexion and rotation has not been investigated in modern total knee arthroplasty (TKA) designs. The present study aimed to determine the contact stress in five posterior-stabilized fixed-bearing TKA designs. HYPOTHESIS: We hypothesized that the contact area and stresses at the tibiofemoral articular surfaces vary according to the type of implant design and tested condition. MATERIALS AND METHODS: The contact area and mean and peak contact stresses at the tibiofemoral articular surfaces were determined when a compressive load of 1200N was applied to a NexGen LPS Flex, Scorpio NRG, Genesis II, PFC Sigma, and Foundation implant. Measurements were performed at 0° and 45° flexion with 0°, 5°, 10°, and 15° rotation, and at 90° and 135° flexion with 0, 5°, 10°, 15°, and 20° rotation. RESULTS: The LPS Flex showed that the femoral component could not achieve 20° rotation at 135° flexion. The Scorpio NRG showed less than 20MPa of contact stress at all conditions. The Genesis II showed higher contact stress than 20MPa at 135° flexion with 20° rotation. The PFC Sigma showed that the femoral component could not achieve >10° rotation at any flexion angle. The Foundation showed more than 20MPa of contact stress at 90° flexion with 20° rotation and at 135° flexion with 10°, 15°, and 20° rotation. DISCUSSION: Surgeons should be more aware of the variable contact conditions of the tibiofemoral articular surfaces in individual TKA designs. LEVEL OF EVIDENCE: Level IV, basic science study.


Asunto(s)
Artroplastia de Reemplazo de Rodilla/instrumentación , Prótesis de la Rodilla , Diseño de Prótesis , Estrés Mecánico , Fenómenos Biomecánicos , Fémur , Articulación de la Rodilla/fisiopatología , Articulación de la Rodilla/cirugía , Ensayo de Materiales , Rango del Movimiento Articular , Rotación , Tibia
9.
Br J Dermatol ; 178(6): 1373-1382, 2018 06.
Artículo en Inglés | MEDLINE | ID: mdl-29238954

RESUMEN

BACKGROUND: Interleukin (IL)-25 is a member of the IL-17 family, which can promote and augment T-helper (Th) type 2 responses. The expression of IL-25 and its cognate receptor, IL-25 receptor (IL-25R), is upregulated and correlated with disease activity in Th2-associated diseases. OBJECTIVES: To examine the expression and function of IL-25 in cutaneous T-cell lymphoma (CTCL). METHODS: Expression and location of IL-25 in lesional skin was investigated with immunohistochemistry. The effect of various cytokines on IL-25 production from normal human epidermal keratinocytes was assessed by quantitative reverse-transcription real-time polymerase chain reaction. Serum IL-25 levels were measured by enzyme-linked immunosorbent assay. The direct effect of IL-25 on tumour cells was also examined using CTCL cell lines and peripheral blood mononuclear cells in patients with Sézary syndrome. RESULTS: IL-25 expression was increased in epidermal keratinocytes in lesional skin of CTCL. Th2 cytokines, IL-4 and IL-13, and periostin induced IL-25 expression by normal human epidermal keratinocytes. Serum IL-25 levels were increased in patients with advanced CTCL and correlated with serum lactate dehydrogenase levels. MyLa cells expressed IL-25R and its expression was augmented by stimulation with IL-25. IL-25 enhanced IL-13 production from MyLa cells via phosphorylation of signal transducer and activator of transcription 6. Peripheral blood mononuclear cells from one patient with Sézary syndrome expressed IL-25R and showed increase of IL-13 production by IL-25. CONCLUSIONS: Th2 cytokines highly expressed in CTCL lesional skin induce IL-25 production by epidermal keratinocytes, which may, in turn, lead to formation of a Th2-dominant microenvironment through the direct induction of IL-13 by tumour cells.


Asunto(s)
Interleucina-17/fisiología , Linfoma Cutáneo de Células T/inmunología , Células Th2/inmunología , Microambiente Tumoral/inmunología , Línea Celular , Progresión de la Enfermedad , Femenino , Humanos , Interleucina-13/biosíntesis , Interleucina-17/metabolismo , Queratinocitos/inmunología , Leucocitos Mononucleares/metabolismo , Masculino , Persona de Mediana Edad , Fosforilación/inmunología , Receptores de Interleucina/inmunología , Factor de Transcripción STAT6/metabolismo , Regulación hacia Arriba/inmunología
10.
Oncogene ; 37(6): 777-786, 2018 02 08.
Artículo en Inglés | MEDLINE | ID: mdl-29059154

RESUMEN

Glioblastoma has the poorest prognosis, and is characterized by excessive invasion and angiogenesis. To determine the invasive mechanisms, we previously used two glioma cell lines (J3T-1 and J3T-2) with different invasive phenotypes. The J3T-1 showed abundant angiogenesis and tumor cell invasion around neovasculature, while J3T-2 showed diffuse cell infiltration into surrounding healthy parenchyma. Microarray analyses were used to identify invasion-related genes in J3T-2 cells, and the expressed genes and their intracellular and intratumoral distribution patterns were evaluated in J3T-2 cell lines, human glioma cell lines, human glioblastoma stem cells and human glioblastoma specimens. To determine the role of the invasion-related genes, invasive activities were evaluated in vitro and in vivo. Fibroblast growth factor 13 (FGF13) was overexpressed in J3T-2 cells compared to J3T-1 cells, and in human glioma cell lines, human glioblastoma stem cells and human glioblastoma specimens, when compared to that of normal human astrocytes. Immunohistochemical staining and the RNA-seq (sequencing) data from the IVY Glioblastoma Atlas Project showed FGF13 expression in glioma cells in the invasive edges of tumor specimens. Also, the intracellular distribution was mainly in the cytoplasm of tumor cells and colocalized with tubulin. Overexpression of FGF13 stabilized tubulin dynamics in vitro and knockdown of FGF13 decreased glioma invasion both in vitro and in vivo and prolonged overall survival of several xenograft models. FGF13 was negatively regulated by hypoxic condition. Silencing of FGF13 also decreased in vivo bevacizumab-induced glioma invasion. In conclusion, FGF13 regulated glioma cell invasion and bevacizumab-induced glioma invasion, and could be a novel target for glioma treatment.


Asunto(s)
Bevacizumab/farmacología , Biomarcadores de Tumor/metabolismo , Neoplasias Encefálicas/patología , Factores de Crecimiento de Fibroblastos/metabolismo , Regulación Neoplásica de la Expresión Génica/efectos de los fármacos , Glioblastoma/patología , Células Madre Neoplásicas/patología , Animales , Apoptosis , Biomarcadores de Tumor/genética , Neoplasias Encefálicas/tratamiento farmacológico , Neoplasias Encefálicas/genética , Neoplasias Encefálicas/metabolismo , Movimiento Celular , Proliferación Celular , Femenino , Factores de Crecimiento de Fibroblastos/genética , Estudios de Seguimiento , Glioblastoma/tratamiento farmacológico , Glioblastoma/genética , Glioblastoma/metabolismo , Humanos , Ratones , Ratones SCID , Invasividad Neoplásica , Células Madre Neoplásicas/efectos de los fármacos , Células Madre Neoplásicas/metabolismo , Pronóstico , Células Tumorales Cultivadas , Ensayos Antitumor por Modelo de Xenoinjerto
11.
Nat Commun ; 6: 7047, 2015 May 11.
Artículo en Inglés | MEDLINE | ID: mdl-25958840

RESUMEN

Ultrafast materials science promises optical control of physical properties of solids. Continuous-wave circularly polarized laser driving was predicted to induce a light-matter coupled state with an energy gap and a quantum Hall effect, coined Floquet topological insulator. Whereas the envisioned Floquet topological insulator requires high-frequency pumping to obtain well-separated Floquet bands, a follow-up question regards the creation of Floquet-like states in graphene with realistic low-frequency laser pulses. Here we predict that short optical pulses attainable in experiments can lead to local spectral gaps and novel pseudospin textures in graphene. Pump-probe photoemission spectroscopy can track these states by measuring sizeable energy gaps and Floquet band formation on femtosecond time scales. Analysing band crossings and pseudospin textures near the Dirac points, we identify new states with optically induced nontrivial changes of sublattice mixing that leads to Berry curvature corrections of electrical transport and magnetization.

14.
Gene Ther ; 22(2): 146-54, 2015 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-25394252

RESUMEN

Reduced expression in immortalized cells/Dickkopf-3 (REIC/Dkk-3) was identified as a gene whose expression is reduced in many human cancers. REIC/Dkk-3 expression is also downregulated in malignant glioma and regulates cell growth through caspase-dependent apoptosis. cRGD (EMD121974), an antagonist of integrins, has demonstrated preclinical efficacy against malignant glioma. In this study, we investigated the antiglioma effect of combination therapy using an adenovirus vector carrying REIC/Dkk-3 (Ad-REIC) and cRGD. Quantitative real-time reverse-transcription PCR revealed the reduction of REIC/Dkk-3 mRNA levels in malignant glioma cell lines. The reduction of REIC/Dkk-3 protein expression in malignant glioma cell lines was also confirmed with western blot analysis. After treatment with Ad-REIC and cRGD, the proliferative rate of malignant glioma cells was significantly reduced in a time-dependent manner. In vivo, there was a statistically significant increase in the survival of mice treated with Ad-REIC and cRGD combination therapy compared with Ad-REIC monotherapy. We identified an apoptotic effect following monotherapy with Ad-REIC. Moreover, cRGD augmented the antiglioma efficacy of Ad-REIC. These results may lead to a promising new approach for the treatment of malignant glioma.


Asunto(s)
Adenoviridae/genética , Antineoplásicos/farmacología , Neoplasias Encefálicas/terapia , Glioma/terapia , Integrinas/antagonistas & inhibidores , Péptidos y Proteínas de Señalización Intercelular/genética , Péptidos Cíclicos/farmacología , Proteínas Adaptadoras Transductoras de Señales , Animales , Antineoplásicos/uso terapéutico , Apoptosis , Astrocitos/metabolismo , Caspasa 8/metabolismo , Caspasa 9/metabolismo , Línea Celular Tumoral , Quimiocinas , Terapia Combinada , Femenino , Técnicas de Silenciamiento del Gen , Terapia Genética , Humanos , Péptidos y Proteínas de Señalización Intercelular/metabolismo , Ratones Endogámicos BALB C , Ratones Desnudos , Venenos de Serpiente , Transducción Genética , Ensayos Antitumor por Modelo de Xenoinjerto
15.
Science ; 344(6185): 725-8, 2014 May 16.
Artículo en Inglés | MEDLINE | ID: mdl-24790028

RESUMEN

Tungsten diselenide (WSe2) and related transition metal dichalcogenides exhibit interesting optoelectronic properties owing to their peculiar band structures originating from the valley degree of freedom. Although the optical generation and detection of valley polarization has been demonstrated, it has been difficult to realize active valley-dependent functions suitable for device applications. We report an electrically switchable, circularly polarized light source based on the material's valley degree of freedom. Our WSe2-based ambipolar transistors emit circularly polarized electroluminescence from p-i-n junctions electrostatically formed in transistor channels. This phenomenon can be explained qualitatively by the electron-hole overlap controlled by the in-plane electric field. Our device demonstrates a route to exploit the valley degree of freedom and the possibility to develop a valley-optoelectronics technology.

16.
Neuroscience ; 272: 34-57, 2014 Jul 11.
Artículo en Inglés | MEDLINE | ID: mdl-24797330

RESUMEN

The anxiolytic diazepam selectively inhibits psychological stress-induced autonomic and behavioral responses without causing noticeable suppression of other central performances. This pharmacological property of diazepam led us to the idea that neurons that exhibit diazepam-sensitive, psychological stress-induced activation are potentially those recruited for stress responses. To obtain neuroanatomical clues for the central stress circuitries, we examined the effects of diazepam on psychological stress-induced neuronal activation in broad brain regions. Rats were exposed to a social defeat stress, which caused an abrupt increase in body temperature by up to 2°C. Pretreatment with diazepam (4mg/kg, i.p.) attenuated the stress-induced hyperthermia, confirming an inhibitory physiological effect of diazepam on the autonomic stress response. Subsequently, the distribution of cells expressing Fos, a marker of neuronal activation, was examined in 113 forebrain and midbrain regions of these rats after the stress exposure and diazepam treatment. The stress following vehicle treatment markedly increased Fos-immunoreactive (IR) cells in most regions of the cerebral cortex, limbic system, thalamus, hypothalamus and midbrain, which included parts of the autonomic, neuroendocrine, emotional and arousal systems. The diazepam treatment significantly reduced the stress-induced Fos expression in many brain regions including the prefrontal, sensory and motor cortices, septum, medial amygdaloid nucleus, medial and lateral preoptic areas, parvicellular paraventricular hypothalamic nucleus, dorsomedial hypothalamus, perifornical nucleus, tuberomammillary nucleus, association, midline and intralaminar thalami, and median and dorsal raphe nuclei. In contrast, diazepam increased Fos-IR cells in the central amygdaloid nucleus, medial habenular nucleus, ventromedial hypothalamic nucleus and magnocellular lateral hypothalamus. These results provide important information for elucidating the neural circuitries that mediate the autonomic and behavioral responses to psychosocial stressors.


Asunto(s)
Diazepam/farmacología , Mesencéfalo/efectos de los fármacos , Neuronas/metabolismo , Prosencéfalo/efectos de los fármacos , Estrés Psicológico/tratamiento farmacológico , Animales , Sistema Nervioso Autónomo/efectos de los fármacos , Sistema Nervioso Autónomo/metabolismo , Conducta Animal , Expresión Génica/efectos de los fármacos , Sistema Límbico/efectos de los fármacos , Sistema Límbico/metabolismo , Masculino , Mesencéfalo/metabolismo , Prosencéfalo/metabolismo , Proteínas Proto-Oncogénicas c-fos/metabolismo , Ratas Long-Evans , Ratas Wistar , Conducta Social , Estrés Fisiológico/efectos de los fármacos
17.
Andrologia ; 46(5): 465-71, 2014 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-23621806

RESUMEN

Pituitary adenylate cyclase-activating peptide (PACAP) is a neuropeptide expressed in the central nervous system and peripheral organs. Previous studies revealed the role and distribution of PACAP in the rodent testis, however, its presence in the human testis and in testicular germ cell tumors is not known. We used RT-PCR and immunohistological observations to investigate whether human testicular tissue and testicular germ cell tumors contain PACAP. The mRNAs for PACAP and its receptors were detected in total RNA extracted from human testes. PACAP immunoreactivity was observed in spermatogonia and spermatids from normal testes. In contrast, diffuse PACAP immunopositivity was observed in seminoma tumor cells, while only faint immunoreactivity was observed in embryonal carcinoma cells. Our data suggest that PACAP may play a role in human spermatogenesis and in testicular germ cell tumor development.


Asunto(s)
Neoplasias de Células Germinales y Embrionarias/metabolismo , Polipéptido Hipofisario Activador de la Adenilato-Ciclasa/metabolismo , Neoplasias Testiculares/metabolismo , Testículo/metabolismo , Adulto , Secuencia de Bases , Cartilla de ADN , Humanos , Masculino , Persona de Mediana Edad , Polipéptido Hipofisario Activador de la Adenilato-Ciclasa/genética , ARN Mensajero/genética , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa
18.
Gen Comp Endocrinol ; 187: 86-94, 2013 Jun 15.
Artículo en Inglés | MEDLINE | ID: mdl-23453966

RESUMEN

Adenosine A1, A2A, A2B and A3 receptor mRNAs were found to be expressed in mouse pancreatic islets and Beta-TC6 cells but their physiological or pharmacological actions are not fully clarified. We showed that adenosine (100 µM) augmented insulin secretion by islets in the presence of either normal (5.5 mM) or a high concentration of glucose (20 mM). The augmentation of insulin secretion in the presence of high glucose was blocked by an A2A antagonist, but not by A2B and A3 antagonists, while an A1 antagonist potentiated the adenosine effect. An adenosine analogue 5'-N-ethylcarboxamidoadenosine (NECA) as well as A1, A2A and A3 receptor agonists also produced stimulation. On the other hand, an A3 agonist markedly reduced Beta-TC6 cell proliferation and the islet cell viability, while adenosine and NECA did not. The effect of A3 agonist was partially blocked by the A3 antagonist. In addition, treatment with the A3 agonist produced a small but significant extent of apoptosis in Beta-TC6 cells as judged by terminal transferase-mediated deoxyuridine triphosphate nick end labeling (TUNEL) assay. These results combined together suggested that like the A1 receptor, activation of A2A receptors by adenosine results in augmented insulin secretion, while the A3 receptor is involved in modulation of the survival of pancreatic ß-cells.


Asunto(s)
Células Secretoras de Insulina/citología , Células Secretoras de Insulina/metabolismo , Insulina/metabolismo , Islotes Pancreáticos/citología , Islotes Pancreáticos/metabolismo , Receptores Purinérgicos P1/metabolismo , Adenosina/farmacología , Animales , Western Blotting , Línea Celular , Proliferación Celular/efectos de los fármacos , Supervivencia Celular/efectos de los fármacos , Cricetinae , Glucosa/farmacología , Etiquetado Corte-Fin in Situ , Células Secretoras de Insulina/efectos de los fármacos , Islotes Pancreáticos/efectos de los fármacos , Masculino , Ratones , Ratones Endogámicos C57BL , Antagonistas de Receptores Purinérgicos P1/farmacología , Ratas , Receptores Purinérgicos P1/genética
19.
Phys Rev Lett ; 109(21): 213001, 2012 Nov 21.
Artículo en Inglés | MEDLINE | ID: mdl-23215591

RESUMEN

The mechanism of DNA modification induced by K-shell photoabsorption of nitrogen and oxygen atoms was investigated by electron paramagnetic resonance and x-ray absorption near edge structure measurements of calf thymus DNA. A g factor of 2.000 for the unpaired electron species, which only arises during irradiation, was measured. The EPR intensities for DNA zwere twofold times larger than those estimated based on the photoabsorption cross section. This suggests that the DNA film itself forms unpaired electron species through the excitation of enhanced electron recapturing, known as the postcollision interaction process.


Asunto(s)
ADN/química , Electrones , Nitrógeno/química , Oxígeno/química , Absorción , Animales , Bovinos , Espectroscopía de Resonancia por Spin del Electrón/métodos , Procesos Fotoquímicos
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