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1.
Phys Rev Lett ; 127(6): 069902, 2021 Aug 06.
Artículo en Inglés | MEDLINE | ID: mdl-34420355

RESUMEN

This corrects the article DOI: 10.1103/PhysRevLett.116.217201.

3.
Pharmazie ; 73(1): 3-8, 2018 Jan 02.
Artículo en Inglés | MEDLINE | ID: mdl-29441943

RESUMEN

For the development of orally available liposomes, understanding the interaction of liposomes with the intestinal mucosa is important. An unstirred water layer (UWL) on the intestinal epithelium surface is a considerable permeability barrier for lipophilic drugs. Therefore, the effects of an UWL on liposome transport across intestinal epithelial cells must be elucidated. We evaluated the effects of the surface charge, particle size, and polyethylene glycol (PEG) modification of liposomes on their association with Caco-2 cells across an UWL. When the association of cationic liposomes with Caco-2 cells was evaluated under a reduction in UWL thickness by shaking, the uptake and/or amount of surface-bound cationic liposomes in cells was increased significantly in a shaking rate-dependent manner. The uptake and/or amount of surface-bound neutral liposomes were increased only at the highest shaking rate. No significant differences in the cellular association of anionic liposomes and PEG-modified liposomes were observed with or without shaking. The association of large liposomes with Caco-2 cells was affected considerably by an UWL compared with that of small liposomes. These results suggest that an UWL affects the surface binding and subsequent uptake of liposomes in Caco-2 cells according to their particle size, surface charge, and PEG modification.


Asunto(s)
Sistemas de Liberación de Medicamentos , Mucosa Intestinal/metabolismo , Polietilenglicoles/química , Agua/química , Administración Oral , Aniones , Transporte Biológico , Células CACO-2 , Cationes , Química Farmacéutica/métodos , Humanos , Liposomas , Tamaño de la Partícula , Permeabilidad
4.
J Fish Biol ; 90(6): 2363-2374, 2017 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-28386984

RESUMEN

This study identified ventilatory and behavioural responses in the marbled sole Pseudopleuronectes yokohamae under experimentally induced progressive decreases in dissolved oxygen (DO) levels. Ventilation frequency showed an increase with decreasing DO levels from normoxia to 2·75 mg O2 l-1 , followed by a decrease in ventilation frequency at decreased DO levels from 2·00 to 0·75 mg O2 l-1 . At DO levels below 2·00 mg l-1 , behaviours at the bottom were suppressed, whereas avoidance behaviours increased. A decrease in avoidance behaviours was observed from 1·00 to 0·75 mg O2 l-1 . Upside-down reversal and incapacitation at DO levels of 1·00-0·75 mg O2 l-1 suggested that sublethal effects on P. yokohamae were induced. The responses observed before the sublethal DO level could be interpreted as an effort to maintain oxygen uptake, reduce routine activities and facilitate avoidance. The observed DO level thresholds that induce behavioural responses, in addition to sublethal effects, indicate hypoxia-tolerance that is important for understanding the effects of hypoxia on coastal ecosystems.


Asunto(s)
Lenguado/fisiología , Oxígeno/análisis , Animales , Conducta Animal , Hipoxia/veterinaria , Respiración , Agua de Mar/química
5.
Phys Rev Lett ; 116(21): 217201, 2016 May 27.
Artículo en Inglés | MEDLINE | ID: mdl-27284670

RESUMEN

A hidden order that emerges in the frustrated pyrochlore Tb_{2+x}Ti_{2-x}O_{7+y} with T_{c}=0.53 K is studied using specific heat, magnetization, and neutron scattering experiments on a high-quality single crystal. Semiquantitative analyses based on a pseudospin-1/2 Hamiltonian for ionic non-Kramers magnetic doublets demonstrate that it is an ordered state of electric quadrupole moments. The elusive spin liquid state of the nominal Tb_{2}Ti_{2}O_{7} is most likely a U(1) quantum spin-liquid state.

7.
Pharmazie ; 71(11): 619-624, 2016 Nov 02.
Artículo en Inglés | MEDLINE | ID: mdl-29441964

RESUMEN

Macrophages have been assumed to have a crucial role in the development of inflammatory bowel disease (IBD). However, involvement of intestinal macrophages in IBD onset and functional alterations of macrophages during IBD development has not been clarified. We investigated the effect of exposure of compounds used in the induction of colitis in mice on the immune responses of peritoneal macrophages in mice. 2,4,6- trinitrobenzenesulfonic acid and oxazolone did not affect the production of interleukin (IL)-10 and IL-12 from lipopolysaccharide (LPS)-stimulated peritoneal macrophages from BALB/c mice. A significant increase in IL-10 secretion and decrease in IL-12 production from LPS-stimulated macrophages were observed upon exposure to dextran sodium sulfate (DSS). TNF-α production was enhanced significantly by exposure to DSS and LPS. The level of nitric-oxide production from macrophages was increased slightly by exposure to DSS and LPS. Expression of sphingosine kinase-1 and LIGHT (both of which are specific biomarkers of M2b macrophages) was observed in macrophages upon DSS exposure. Alteration of cytokine production in macrophages was observed upon DSS exposure in the absence of LPS stimulation. Peritoneal macrophages from C57BL/6 mice showed similar responses to peritoneal macrophages from BALB/c mice against DSS. These results suggest that DSS directs the immune response of macrophages towards the M2b phenotype.


Asunto(s)
Citocinas/biosíntesis , Sulfato de Dextran/farmacología , Macrófagos Peritoneales/metabolismo , Animales , Colitis/inducido químicamente , Colitis/patología , Femenino , Técnicas In Vitro , Interleucina-10/biosíntesis , Interleucina-10/genética , Interleucina-12/biosíntesis , Interleucina-12/genética , Lipopolisacáridos/farmacología , Macrófagos Peritoneales/efectos de los fármacos , Ratones , Ratones Endogámicos BALB C , Ratones Endogámicos C57BL , Óxido Nítrico/biosíntesis , Fosfotransferasas (Aceptor de Grupo Alcohol)/biosíntesis , Fosfotransferasas (Aceptor de Grupo Alcohol)/genética , Especificidad de la Especie , Miembro 14 de la Superfamilia de Ligandos de Factores de Necrosis Tumoral/biosíntesis , Miembro 14 de la Superfamilia de Ligandos de Factores de Necrosis Tumoral/genética
8.
Phys Rev Lett ; 114(3): 037202, 2015 Jan 23.
Artículo en Inglés | MEDLINE | ID: mdl-25659018

RESUMEN

High-precision dc magnetization measurements have been made on Cu(C4H4N2) (NO3)2 in magnetic fields up to 14.7 T, slightly above the saturation field Hs=13.97 T, in the temperature range from 0.08 to 15 K. The magnetization curve and differential susceptibility at the lowest temperature show excellent agreement with exact theoretical results for the spin-1/2 Heisenberg antiferromagnet in one dimension. A broad peak is observed in magnetization measured as a function of temperature, signaling a crossover to a low-temperature Tomonaga-Luttinger-liquid regime. With an increasing field, the peak moves gradually to lower temperatures, compressing the regime, and, at Hs, the magnetization exhibits a strong upturn. This quantum critical behavior of the magnetization and that of the specific heat withstand quantitative tests against theory, demonstrating that the material is a practically perfect one-dimensional spin-1/2 Heisenberg antiferromagnet.

10.
Nature ; 451(7180): 814-7, 2008 Feb 14.
Artículo en Inglés | MEDLINE | ID: mdl-18273016

RESUMEN

The composition of the mantle transition region, characterized by anomalous seismic-wave velocity and density changes at depths of approximately 400 to 700 km, has remained controversial. Some have proposed that the mantle transition region has an olivine-rich 'pyrolite' composition, whereas others have inferred that it is characterized by pyroxene- and garnet-rich compositions ('piclogite'), because the sound velocities in pyrolite estimated from laboratory data are substantially higher than those seismologically observed. Although the velocities of the olivine polymorphs at these pressures (wadsleyite and ringwoodite) have been well documented, those of majorite (another significant high-pressure phase in the mantle transition region) with realistic mantle compositions have never been measured. Here we use combined in situ X-ray and ultrasonic measurements under the pressure and temperature conditions of the mantle transition region to show that majorite in a pyrolite composition has sound velocities substantially lower than those of earlier estimates, owing to strong nonlinear decreases at high temperature, particularly for shear-wave velocity. We found that pyrolite yields seismic velocities more consistent with typical seismological models than those of piclogite in the upper to middle parts of the region, except for the potentially larger velocity jumps in pyrolite relative to those observed at a depth of 410 km. In contrast, both of these compositions lead to significantly low shear-wave velocities in the lower part of the region, suggesting possible subadiabatic temperatures or the existence of a layer of harzburgite-rich material supplied by the subducted slabs stagnant at these depths.

11.
Sarcoidosis Vasc Diffuse Lung Dis ; 30(1): 43-51, 2013 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-24003534

RESUMEN

BACKGROUND: The serum Krebs von der Lungen-6 (KL-6) level is a useful marker correlated with the severity of various interstitial lung diseases. There have been few reports about the clinical characteristics of organizing pneumonia (OP) associated with the serum KL-6 levels. OBJECTIVE: This study was performed to determine whether the serum KL-6 levels can help determine the optimal treatment for OP. DESIGNS: Patients diagnosed with OP by clinical, radiological and histopathological findings were retrospectively reviewed. The OP patients were classified into two groups based on their serum KL-6 levels: normal KL-6 and high KL-6 groups. The two groups were compared with regard to their clinical and radiological data and therapeutic response one month after the start of treatment. RESULTS: The clinical records of twenty-two patients diagnosed with OP were reviewed. The serum KL-6 level was elevated in 11 of the 22 patients. There were no obvious differences in the clinical data between the two groups, although patients in the normal KL-6 group tended to have a fever. There were no significant differences in the chest X-ray (CXR) score or computed tomography (CT) score between the two groups. The CXR scores were correlated with the serum KL-6 levels. At 1 month after the diagnosis, 11 patients who needed treatment with prednisolone were included in the high KL-6 group. CONCLUSIONS: Patients with normal KL-6 levels showed lower CXR and CT scores. The serum KL-6 level on admission is a useful marker to judge the need for corticosteroid treatment in OP patients.


Asunto(s)
Biomarcadores/sangre , Neumonía en Organización Criptogénica/sangre , Mucina-1/sangre , Corticoesteroides/uso terapéutico , Broncoscopía , Neumonía en Organización Criptogénica/diagnóstico , Neumonía en Organización Criptogénica/diagnóstico por imagen , Neumonía en Organización Criptogénica/tratamiento farmacológico , Femenino , Humanos , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Tomografía Computarizada por Rayos X
12.
J Chem Phys ; 138(2): 024302, 2013 Jan 14.
Artículo en Inglés | MEDLINE | ID: mdl-23320678

RESUMEN

Cascade Si LVV Auger decays following KL(23)L(23) Auger transitions have been measured in SiF(4) molecule using an electron spectrometer combined with monochromatized undulator radiation. Molecular cascade processes from the two 2p holes states largely generate wide band structures in the spectra due to sequential electron emission leading to multiple valence holes. However, a peak with high yield is observed for the first time at about 103 eV, an energy being considerably higher than the energies of the normal LVV Auger electron, in the instance of the resonant excitation of Si 1s electron into the vacant molecular orbital. This peak is presumed to originate from the participator decay from the state with two 2p holes and one excited electron into the state with one 2p hole and one valence hole. A similar peak with less intensity is detected in the photoexcitation of the 1s electron into a Rydberg orbital. After the normal KL(23)L(23) Auger transition, the resultant cascade spectrum shows several peaks, e.g., 61 eV, 76 eV, and 82 eV. The former two peaks are assigned to the Auger transitions of Si atoms produced through molecular ion dissociation after cascade decays, and the latter is probably ascribed to the second step Auger decay into states having a 2p hole together with two valence holes.

13.
Pharmazie ; 67(5): 400-5, 2012 May.
Artículo en Inglés | MEDLINE | ID: mdl-22764571

RESUMEN

Gene therapy is a promising treatment option for cancers generated by mutation of oncogenes or tumor suppressor genes. The transcriptional process is activated by doxorubicin (DXR), and gene expression efficiency followed by gene transfection can be enhanced by the combination-use of DXR. Therefore, co-encapsulation of plasmid DNA (pDNA) and DXR into non-viral gene carriers can enhance gene expression. Here, we prepared DXR-loaded liposome/pDNA complexes (DXR-loaded PEGylated lipoplexes) by co-encapsulating pDNA and DXR into liposomes. Gene expression was enhanced by DXR encapsulation into lipoplexes in colon-26 cells and cultured mouse macrophages, and this gene expression level was significantly higher than that obtained by the combination of PEGylated lipoplexes and free DXR. Moreover, the activation profiles of transcriptional factors induced by DXR-loaded lipoplexes were different from those induced by free DXR; therefore, co-encapsulation of pDNA and DXR into gene carriers might be contributed to effective enhancement of gene expression. These findings provide a new approach for achieving effective gene transfection using PEGylated lipoplexes.


Asunto(s)
Antibióticos Antineoplásicos/administración & dosificación , Antibióticos Antineoplásicos/farmacología , ADN/administración & dosificación , ADN/genética , Doxorrubicina/administración & dosificación , Doxorrubicina/farmacología , Expresión Génica/efectos de los fármacos , Activación Transcripcional/efectos de los fármacos , Análisis de Varianza , Animales , Línea Celular , Colorantes , ADN/biosíntesis , Portadores de Fármacos , Femenino , Liposomas , Macrófagos/metabolismo , Ratones , Ratones Endogámicos BALB C , FN-kappa B/genética , Tamaño de la Partícula , Polietilenglicoles , Reacción en Cadena en Tiempo Real de la Polimerasa , Sales de Tetrazolio , Tiazoles , Factor de Transcripción AP-1/genética
16.
J Chem Phys ; 134(8): 084312, 2011 Feb 28.
Artículo en Inglés | MEDLINE | ID: mdl-21361544

RESUMEN

Spectator resonant KL(23)L(23) Auger electron spectra have been measured in the Si 1s photoexcitation region of Si(CH(3))(4) using monochromatized undulator radiation combined with a hemispherical electron spectrometer. The broad peak with high intensity in a total ion yield spectrum, coming mainly from excitation of a 1s electron into the 6t(2) vacant orbital, induces a spectator Auger decay in which the excited electron remains in its excited orbital. The component on the higher energy side of this peak through 1s excitation into a Rydberg orbital produces resonant Auger decays in which the excited Rydberg electron moves into a slightly higher Rydberg orbital, or is partly shaken up to a significantly higher Rydberg orbital. These findings of Si(CH(3))(4) indicate a clear contrast to those for SiF(4), in which the 1s excitation into a Rydberg orbital induces a shake-down phenomenon as well as a shake-up one. The results of these molecules exhibit a clear splitting effect among excited orbitals which are smeared out by overlapping due to lifetime widths and due to densely populated levels in the 1s electron excitation spectrum. This is consistent with the calculation on photoexcitation within the framework of density functional theory.

17.
J Econ Entomol ; 101(4): 1432-8, 2008 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-18767757

RESUMEN

Susceptibility to oxydemeton-methyl and imidacloprid, and the inhibitory effects of oxydemeton-methyl and some organophosphate compounds on acetylcholinesterase (AChE) and carboxylesterase activity were studied in two populations (Karaj and Rasht) of green peach aphids, Myzus persicae (Sulzer). Results show that the Karaj population was resistant to oxydemeton-methyl but susceptible to imidacloprid. The esterase activity of the resistant and susceptible populations suggests that one of the resistance mechanisms to oxydemeton-methyl was esterase-based. The inhibition assay shows that the AChE of the Karaj population is less sensitive to oxydemeton-methyl and paraoxon derivatives. Regarding the paraoxon derivatives, the smaller paraoxon side chain is more potent against the modified AChE than against the AChE from the susceptible strain. Fertility life table parameters of green peach aphid populations resistant and susceptible to oxydemeton-methyl also were studied under laboratory conditions. The standard errors of the population growth parameters were calculated using the Jackknife method. Results showed that susceptible strain exhibits a significantly higher r(m) than the resistant strain, probably because the resistant strain had a higher generation time than the susceptible strain. These results suggested that the resistant Karaj strain may be less fit than the susceptible strain.


Asunto(s)
Acetilcolinesterasa/metabolismo , Áfidos/fisiología , Imidazoles , Insecticidas , Nitrocompuestos , Compuestos Organotiofosforados , Animales , Inhibidores de la Colinesterasa , Resistencia a los Insecticidas , Estadios del Ciclo de Vida , Neonicotinoides , Paraoxon/análogos & derivados
18.
Nat Commun ; 8(1): 1198, 2017 10 31.
Artículo en Inglés | MEDLINE | ID: mdl-29084963

RESUMEN

The behavior of the f-electrons in the lanthanides and actinides governs important macroscopic properties but their pressure and temperature dependence is not fully explored. Cerium with nominally just one 4f electron offers a case study with its iso-structural volume collapse from the γ-phase to the α-phase ending in a critical point (p C, V C, T C), unique among the elements, whose mechanism remains controversial. Here, we present longitudinal (c L) and transverse sound speeds (c T) versus pressure from higher than room temperature to T C for the first time. While c L experiences a non-linear dip at the volume collapse, c T shows a step-like change. This produces very peculiar macroscopic properties: the minimum in the bulk modulus becomes more pronounced, the step-like increase of the shear modulus diminishes and the Poisson's ratio becomes negative-meaning that cerium becomes auxetic. At the critical point itself cerium lacks any compressive strength but offers resistance to shear.

19.
Aliment Pharmacol Ther ; 45(1): 169-177, 2017 01.
Artículo en Inglés | MEDLINE | ID: mdl-27862091

RESUMEN

BACKGROUND: Abdominal ultrasound fails to detect over one-fourth of hepatocellular carcinoma (HCC) at an early stage in patients with cirrhosis. Identifying patients in whom ultrasound is of inadequate quality can inform interventions to improve surveillance effectiveness. AIM: To evaluate and identify predictors of ultrasound quality in patients with cirrhosis. METHODS: We performed a retrospective cohort study among patients who underwent ultrasound examination for a cirrhosis-related indication between April 2015 and October 2015. Three fellowship-trained abdominal radiologists collectively reviewed all ultrasound exams and categorised exam quality as definitely adequate, likely adequate, likely inadequate and definitely inadequate to exclude liver lesions. We performed multivariable logistic regression to determine characteristics associated with inadequate ultrasound quality. RESULTS: Among 941 patients, 191 (20.3%) ultrasounds were inadequate for excluding HCC- 134 definitely inadequate and 57 likely inadequate. In multivariable analysis, inadequate quality was associated with male gender (OR 1.68, 95% CI 1.14-2.48), body mass index category (OR 1.67, 95% CI 1.45-1.93), Child-Pugh B or C cirrhosis (OR 1.93, 95% CI 1.32-2.81), alcohol-related cirrhosis (OR 2.11, 95% CI 1.33-3.37), NASH cirrhosis (OR 2.87, 95% CI 1.71-4.80), and in-patient status (OR 1.55, 95% CI 1.01-2.37). Ultrasounds were inadequate in over one-third of patients with Child-Pugh C cirrhosis, BMI >35, or NASH cirrhosis. CONCLUSIONS: One in five ultrasounds in patients with cirrhosis are inadequate for exclusion of HCC, which can contribute to surveillance failure. Alternative surveillance modalities are needed in subgroups prone to inadequate ultrasounds including obese patients, those with Child Pugh B or C cirrhosis, and those with alcohol- or NASH-related cirrhosis.


Asunto(s)
Carcinoma Hepatocelular/diagnóstico por imagen , Cirrosis Hepática/diagnóstico por imagen , Neoplasias Hepáticas/diagnóstico por imagen , Vigilancia de la Población , Ultrasonografía/normas , Adulto , Anciano , Carcinoma Hepatocelular/epidemiología , Estudios de Cohortes , Femenino , Humanos , Cirrosis Hepática/epidemiología , Neoplasias Hepáticas/epidemiología , Masculino , Persona de Mediana Edad , Vigilancia de la Población/métodos , Valor Predictivo de las Pruebas , Estudios Retrospectivos
20.
Novartis Found Symp ; 277: 74-84; discussion 84-6, 251-3, 2006.
Artículo en Inglés | MEDLINE | ID: mdl-17319155

RESUMEN

Dengue viruses (DENV) have 5'-capped RNA genomes of (+) polarity and encode a single polyprotein precursor that is processed into mature viral proteins. NS2B, NS3 and NS5 proteins catalyse/activate enzyme activities that are required for key processes in the virus life cycle. The heterodimeric NS2B/NS3 is a serine protease required for processing. Using a high-throughput protease assay, we screened a small molecule chemical library and identified -200 compounds having > or = 50% inhibition. Moreover, NS3 exhibits RNA-stimulated NTPase, RNA helicase and the 5'-RNA triphosphatase activities. The NTPase and the 5'-RTPase activities of NS3 are stimulated by interaction with NS5. Moreover, the conserved, positively charged motif in DENV-2 NS3, 184RKRK, is required for RNA binding and modulates the RNA-dependent enzyme activities of NS3. To study viral replication, a variety of methods are used such as the in vitro RNA-dependent RNA polymerase assays that utilize lysates from DENV-2-infected mosquito or mammalian cells or the purified NS5 along with exogenous short subgenomic viral RNAs or the replicative intracellular membrane-bound viral RNAs as templates. In addition, a cell-based DENV-2 replicon RNA encoding a luciferase reporter is also used to examine the role of cis-acting elements within the 3' UTR and the RKRK motif in viral replication.


Asunto(s)
Flavivirus/enzimología , Nucleósido-Trifosfatasa/metabolismo , ARN Helicasas/metabolismo , ARN Polimerasa Dependiente del ARN/metabolismo , Proteínas no Estructurales Virales/metabolismo , Secuencia de Aminoácidos , Datos de Secuencia Molecular , Homología de Secuencia de Aminoácido
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