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1.
Nature ; 575(7783): 468-472, 2019 11.
Artículo en Inglés | MEDLINE | ID: mdl-31597164

RESUMEN

Heat pumps based on magnetocaloric and electrocaloric working bodies-in which entropic phase transitions are driven by changes of magnetic and electric field, respectively-use displaceable fluids to establish relatively large temperature spans between loads to be cooled and heat sinks1,2. However, the performance of prototypes is limited because practical magnetocaloric working bodies driven by permanent magnets3-5 and electrocaloric working bodies driven by voltage6-16 display temperature changes of less than 3 kelvin. Here we show that high-quality multilayer capacitors of PbSc0.5Ta0.5O3 display large electrocaloric effects over a wide range of starting temperatures when the first-order ferroelectric phase transition is driven supercritically (as verified by Landau theory) above the Curie temperature of 290 kelvin by electric fields of 29.0 volts per micrometre. Changes of temperature in the large central area of the capacitor peak at 5.5 kelvin near room temperature and exceed 3 kelvin for starting temperatures that span 176 kelvin (complete thermalization would reduce these values from 5.5 to 3.3 kelvin and from 176 to 73 kelvin). If magnetocaloric working bodies were to be replaced with multilayer capacitors of PbSc0.5Ta0.5O3, then the established design principles behind magnetocaloric heat pumps could be repurposed for better performance without bulky and expensive permanent magnets.

2.
J Clin Microbiol ; 56(9)2018 09.
Artículo en Inglés | MEDLINE | ID: mdl-30021821

RESUMEN

Loop-mediated isothermal amplification (LAMP) is a potential screening test for avian influenza (AI), but its narrow detection spectrum limits its applications. To improve this narrow detection spectrum, 3 types of primers were compared for detection of diverse H5 subtype hemagglutinin (HA) genes. Four and 6 genes, of 10 genetically different H5 HA genes tested, were detected with S primers specific for A/duck/Tsukuba/9/2005 (H5N2) and with M primers (which contained mixed bases), respectively. In contrast, all 10 HA genes became positive with population primers (P primers) (a mixture of primers designed for each subpopulation of 2,202 HA genes). Our study indicated that the P primers for the forward inner primer (FIP) and backward inner primer (BIP) sites were essential for exhaustive detection, whereas those for the F3, forward loop (FL), backward loop (BL), and B3 sites were exchangeable with M primers. A base mismatch experiment demonstrated that HA genes with ≤2 base mismatches per primer site and ≤10 base mismatches per HA gene were amplifiable. Reverse transcription-LAMP was broadly reactive, specific for H5 subtype HA genes, and applicable to field samples, with the sensitivity of real-time PCR. The in silico analysis suggested that most H5 HA genes (2,586 positive genes/2,588 genes tested) registered in the GenBank database might be amplifiable. These results indicate that the use of subpopulation primers in LAMP allows exhaustive detection of diverse HA genes and H5 LAMP can be used as a reliable AI screening test in general diagnostic laboratories.


Asunto(s)
Glicoproteínas Hemaglutininas del Virus de la Influenza/genética , Virus de la Influenza A/genética , Gripe Aviar/virología , Técnicas de Amplificación de Ácido Nucleico/métodos , Animales , Animales Salvajes , Aves , Cartilla de ADN/genética , Virus de la Influenza A/aislamiento & purificación , Gripe Aviar/diagnóstico , Sondas de Oligonucleótidos/genética , ARN Viral/genética , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Sensibilidad y Especificidad , Análisis de Secuencia de ADN
3.
Nat Mater ; 13(6): 611-8, 2014 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-24705382

RESUMEN

Resonant X-ray diffraction (RXD) uses X-rays in the vicinity of a specific atomic absorption edge and is a powerful technique for studying symmetry breaking by motifs of various multipole moments, such as electric monopoles (charge), magnetic dipoles (spin) and electric quadrupoles (orbital). Using circularly polarized X-rays, this technique has been developed to verify symmetry breaking effects arising from chirality, the asymmetry of an object upon its mirroring. Chirality plays a crucial role in the emergence of functionalities such as optical rotatory power and multiferroicity. Here we apply spatially resolved RXD to reveal the helix chirality of Dy 4f electric quadrupole orientations and its domain structure in DyFe3(BO3)4, which shows a reversible phase transition into an enantiomorphic space-group pair. The present study provides evidence for a helix chiral motif of quadrupole moments developed in crystallographic helix chirality.

4.
Phys Rev Lett ; 109(16): 167206, 2012 Oct 19.
Artículo en Inglés | MEDLINE | ID: mdl-23215123

RESUMEN

High-resolution ultrasonic velocity measurements have been used to determine the temperature-magnetic-field phase diagram of the monoclinic multiferroic CuO. A new transition at T(N3)=230 K, corresponding to an intermediate state between the antiferromagnetic noncollinear spiral phase observed below T(N2)=229.3 K and the paramagnetic phase, is revealed. Anomalies associated with a first order transition to the commensurate collinear phase are also observed at T(N1)=213 K. For fields with B || b, a spin-flop transition is detected between 11 T-13 T at lower temperatures. Moreover, our analysis using a Landau-type free energy clearly reveals the necessity for an incommensurate collinear phase between the spiral and the paramagnetic phase. This model is also relevant to the phase diagrams of other monoclinic multiferroic systems.

5.
Poult Sci ; 91(10): 2496-501, 2012 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-22991533

RESUMEN

Japanese quail (Coturnix japonica) are farmed worldwide as poultry. Quail have been used as experimental animals in various scientific fields, but their immunological characteristics have not been well characterized. In this study, to develop a method for analyzing the innate immune response of quail to infectious pathogens, we determined the nucleotide sequences of major interleukins (IL) and Toll-like receptor (TLR)-7 of quail and developed quantitative real-time PCR assays. The nucleotide sequences of quail IL-1ß, IL-4, IL-6, IL-8, IL-10, IL-12a, IL-12b, IL-13, IL-18, and TLR-7 were determined based on the sequences of the chicken genes. Specific primers for each of these genes and previously reported interferon (IFN)-α, IFN-γ, and IL-2 genes were designed for quantitative real-time PCR. Standard curves for quantification were established using serial dilutions of external standard plasmids containing real-time PCR products. Then, real-time PCR was performed to monitor the kinetics of quail immune-related gene expression induced in splenocytes stimulated with concanavalin A. After amplification, the r(2) values of the standard curves for all target genes were above 0.980. Melting analysis of real-time PCR revealed specific amplification of each gene that could be visualized clearly as a single peak of melting temperature in a melt peak chart. These data show that the mRNA expressions of quail immune-related genes can be accurately quantified using this real-time PCR assay. In this study, we showed the nucleotide sequences of several quail cytokine mRNA and constructed the quantitative real-time PCR for quail immune-related genes.


Asunto(s)
Coturnix/metabolismo , Interferones/metabolismo , Interleucinas/metabolismo , Reacción en Cadena en Tiempo Real de la Polimerasa/veterinaria , Bazo/citología , Receptor Toll-Like 7/metabolismo , Animales , Concanavalina A/toxicidad , Regulación de la Expresión Génica/efectos de los fármacos , Regulación de la Expresión Génica/fisiología , Interferones/genética , Interleucinas/genética , Sensibilidad y Especificidad , Bazo/efectos de los fármacos , Receptor Toll-Like 7/genética
6.
Lupus ; 20(8): 792-800, 2011 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-21562022

RESUMEN

Our aim was to analyze the performance of an interferon-gamma release assay, QuantiFERON-TB Gold (QFT-2G), for diagnosing Mycobacterium tuberculosis (MTB) infection in patients with systemic lupus erythematosus (SLE). We performed the QFT-2G and tuberculin skin test (TST) in 71 SLE patients. The QFT-2G results of 279 patients with other connective tissue diseases (CTD) and 35 healthy controls were analyzed. Of the 71 SLE patients, two (2.8%) were positive and 46 (64.8%) were negative by QFT-2G. All SLE patients had no evidence of active MTB infection, apart from one. QFT-2G produced a significantly higher number of indeterminate results in patients with SLE (23/71, 32.4%) compared with those with other CTD (5.7%) or healthy controls (0%) (p < 0.0001 and p < 0.0001). Decreased lymphocyte counts and high SLEDAI scores in SLE patients were shown to be risk factors for indeterminate results by multivariate analysis (p = 0.02 and p = 0.04). Among all patients with CTD, SLE itself and lymphocytopenia were found to be independent risks for indeterminate results (p = 0.00000625 and p = 0.000107). In conclusion, QFT-2G may have more potential to assist in the diagnosis of active and latent MTB infection than TST in SLE patients. However, because of the high frequency of indeterminate results, caution must be used when interpreting the results of QFT-2G among SLE patients, especially those who have parallel or subsequent flares.


Asunto(s)
Interferón gamma/inmunología , Interferón gamma/metabolismo , Lupus Eritematoso Sistémico/inmunología , Lupus Eritematoso Sistémico/microbiología , Mycobacterium tuberculosis/inmunología , Prueba de Tuberculina/métodos , Tuberculosis/diagnóstico , Adolescente , Adulto , Anciano , Femenino , Humanos , Masculino , Persona de Mediana Edad , Factores de Riesgo , Tuberculosis/inmunología , Adulto Joven
7.
J Exp Med ; 192(1): 41-52, 2000 Jul 03.
Artículo en Inglés | MEDLINE | ID: mdl-10880525

RESUMEN

In this study, we show that a single intranasal dose of a plasmid encoding active transforming growth factor beta1 (pCMV-TGF-beta1) prevents the development of T helper cell type 1 (Th1)-mediated experimental colitis induced by the haptenating reagent, 2,4, 6-trinitrobenzene sulfonic acid (TNBS). In addition, such plasmid administration abrogates TNBS colitis after it has been established, whereas, in contrast, intraperitoneal administration of rTGF-beta1 protein does not have this effect. Intranasal pCMV-TGF-beta1 administration leads to the expression of TGF-beta1 mRNA in the intestinal lamina propria and spleen for 2 wk, as well as the appearance of TGF-beta1-producing T cells and macrophages in these tissues, and is not associated with the appearances of fibrosis. These cells cause marked suppression of interleukin (IL)-12 and interferon (IFN)-gamma production and enhancement of IL-10 production; in addition, they inhibit IL-12 receptor beta2 (IL-12Rbeta2) chain expression. Coadministration of anti-IL-10 at the time of pCMV-TGF-beta1 administration prevents the enhancement of IL-10 production and reverses the suppression of IL-12 but not IFN-gamma secretion. However, anti-IL-10 leads to increased tumor necrosis factor alpha production, especially in established colitis. Taken together, these studies show that TGF-beta1 inhibition of a Th1-mediated colitis is due to: (a) suppression of IL-12 secretion by IL-10 induction and (b) inhibition of IL-12 signaling via downregulation of IL-12Rbeta2 chain expression. In addition, TGF-beta1 may also have an inhibitory effect on IFN-gamma transcription.


Asunto(s)
Colitis/terapia , Terapia Genética , Plásmidos/administración & dosificación , Células TH1/inmunología , Factor de Crecimiento Transformador beta/genética , Administración Intranasal , Animales , Colitis/inducido químicamente , Colitis/inmunología , Colitis/prevención & control , Colon/patología , Citocinas/biosíntesis , Citomegalovirus , Inyecciones Intraperitoneales , Mucosa Intestinal/patología , Masculino , Ratones , Ratones Endogámicos , Proteínas Recombinantes/uso terapéutico , Porcinos , Células TH1/efectos de los fármacos , Factor de Crecimiento Transformador beta/uso terapéutico , Ácido Trinitrobencenosulfónico
8.
J Exp Med ; 180(1): 111-21, 1994 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-8006578

RESUMEN

About a half of the antierythrocyte autoantibody transgenic (autoAb Tg) mice, in which almost all B cells are detected in the spleen, lymph nodes, and Peyer's patches, but not in the peritoneal cavity, suffer from autoimmune hemolytic anemia. The occurrence of this disease is strongly linked to production of autoAb by activated peritoneal B-1 cells in the Tg mice. In this study, we have shown that oral administration of lipopolysaccharides (LPS) activated B-1 cells in the lamina propria of the gut as well as the peritoneal cavity in the healthy Tg mice and induced the autoimmune symptoms in all the Tg mice. The activation of peritoneal and lamina propria B-1 cells by enteric LPS is found not only in the anti-RBC autoAb Tg mice and normal mice but also in the aly mice which congenitally lack lymph nodes and Peyer's patches. These results suggest that B-1 cells in the two locations may form a common pool independent of Peyer's patches and lymph nodes, and can be activated by enteric thymus-independent antigens or polyclonal activators such as LPS. The induction of autoimmune hemolytic anemia in the Tg mice by enteric LPS through the activation of B-1 cells in the lamina propria of gut and in the peritoneal cavity suggests that B-1 cells and bacterial infection may play a pathogenic role in the onset of autoimmune diseases.


Asunto(s)
Autoanticuerpos/fisiología , Enfermedades Autoinmunes/etiología , Linfocitos B/inmunología , Intestinos/inmunología , Lipopolisacáridos/farmacología , Activación de Linfocitos , Administración Oral , Animales , Autoanticuerpos/genética , Infecciones Bacterianas/complicaciones , Supresión Clonal , Lipopolisacáridos/administración & dosificación , Masculino , Ratones , Ratones Transgénicos , Cavidad Peritoneal/citología
9.
J Exp Med ; 171(4): 1141-54, 1990 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-2109036

RESUMEN

Studies were made on the effects of in vivo administration of anti-CD4 mAb, anti-CD8 mAb, or a combination of both mAbs on multiplication of bacteria, the levels of serum transaminases, and mortality in mice infected with Listeria monocytogenes. Results showed that in sublethal infection, CD8+ cells enhanced the peak of bacterial multiplication and liver cell necrosis, and CD4+ cells suppressed CD8+ cell-mediated enhancement. Results also showed that either CD4+ or CD8+ cells were necessary for, and capable of, mediating clearance of the bacteria. CD8+ cells were more efficient than CD4+ cells, but for optimal clearance both were necessary. In lethal listeriosis, treatment of mice with anti-CD8 mAb or a combination of both anti-CD4 and anti-CD8 mAbs, but not anti-CD4 mAb only, protected mice from death by decreasing multiplication of bacteria in the liver and spleen after a peak of approximately 10(8) CFU, and lowering the elevated serum levels of transaminases. These findings indicated that CD8+ cells were responsible for causing irreversible systemic Listeria infection and severe liver necrosis. In lethal listeriosis, administration of rMuIFN-gamma markedly prolonged survival by decreasing multiplication of bacteria and promoting recovery from liver necrosis.


Asunto(s)
Antígenos de Diferenciación de Linfocitos T/inmunología , Antígenos CD4/inmunología , Interferón gamma/uso terapéutico , Listeriosis/inmunología , Linfocitos T/inmunología , Alanina Transaminasa/sangre , Animales , Anticuerpos Monoclonales , Aspartato Aminotransferasas/sangre , Antígenos CD8 , Proteínas del Sistema Complemento/inmunología , Femenino , Inmunidad Celular , Listeriosis/patología , Listeriosis/terapia , Hígado/patología , Ratones , Ratones Endogámicos BALB C , Ratones Desnudos , Necrosis , Proteínas Recombinantes , Bazo/inmunología , Linfocitos T/efectos de los fármacos
10.
Science ; 370(6512): 125-129, 2020 10 02.
Artículo en Inglés | MEDLINE | ID: mdl-33004522

RESUMEN

Cooling devices based on caloric materials have emerged as promising candidates to become the next generation of coolers. Several electrocaloric (EC) heat exchangers have been proposed that use different mechanisms and working principles. However, a prototype that demonstrates a competitive temperature span has been missing. We developed a parallel-plate active EC regenerator based on lead scandium tantalate multilayer capacitors. After optimizing the structural design by using finite element modeling for guidance and to considerably improve insulation, we measured a maximum temperature span of 13.0 kelvin. This temperature span breaks a crucial barrier and confirms that EC materials are promising candidates for cooling applications.

11.
J Cell Biol ; 115(5): 1275-82, 1991 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-1955475

RESUMEN

The staurosporine analogues, K-252a and RK-286C, were found to cause DNA re-replication in rat diploid fibroblasts (3Y1) without an intervening mitosis, producing tetraploid cells. Analysis of cells synchronized in early S phase in the presence of K-252a revealed that initiation of the second S phase required a lag period of 8 h after completion of the previous S phase. Reinitiation of DNA synthesis was inhibited by cycloheximide, actinomycin D, and serum deprivation, but not by Colcemid, suggesting that a functional G1 phase dependent on de novo synthesis of protein and RNA is essential for entry into the next S phase. In a src-transformed 3Y1 cell line, as well as other cell lines, giant cells containing polyploid nuclei with DNA contents of 16C to 32C were produced by continuous treatment with K-252a, indicating that the agent induced several rounds of the incomplete cell cycle without mitosis. Although the effective concentration of K-252a did not cause significant inhibition of affinity-purified p34cdc2 protein kinase activity in vitro, in vivo the full activation of p34cdc2 kinase during the G2/M was blocked by K-252a. On the other hand, the cyclic fluctuation of partially activated p34cdc2 kinase activity peaking in S phase still continued. These results suggest that a putative protein kinase(s) sensitive to K-252a plays an important role in the mechanism for preventing over-replication after completion of previous DNA synthesis. They also suggest that a periodic activation of p34cdc2 is required for S phases in the cell cycle without mitosis.


Asunto(s)
Carbazoles/farmacología , Ciclo Celular/efectos de los fármacos , Inhibidores de Proteínas Quinasas , Animales , Línea Celular , Diploidia , Fibroblastos/citología , Citometría de Flujo , Células Gigantes/citología , Alcaloides Indólicos , Mitosis , Ratas , Fase S/efectos de los fármacos
12.
Oncogene ; 26(45): 6488-98, 2007 Oct 04.
Artículo en Inglés | MEDLINE | ID: mdl-17471240

RESUMEN

Defining apoptosis-regulatory cascades of the epithelium is important for understanding carcinogenesis, since cancer cells are considered to arise as a result of the collapse of the cascades. We previously reported that a novel gene GASDERMIN (GSDM) is expressed in the stomach but suppressed in gastric cancer cell lines. Furthermore, in this study, we demonstrated that GSDM is expressed in the mucus-secreting pit cells of the gastric epithelium and frequently silenced in primary gastric cancers. We found that GSDM has a highly apoptotic activity and its expression is regulated by a transcription factor LIM domain only 1 (LMO1) through a sequence to which Runt-related transcription factor 3 (RUNX3) binds, in a GSDM promoter region. We observed coexpression of GSDM with LMO1, RUNX3 and type II transforming growth factor-beta receptor (TGF-betaRII) in the pit cells, and found that TGF-beta upregulates the LMO1- and GSDM-expression in the gastric epithelial cell line and induces apoptosis, which was confirmed by the finding that the apoptosis induction is inhibited by suppression of each LMO1-, RUNX3- and GSDM expression, respectively. The present data suggest that TGF-beta, LMO1, possibly RUNX3, and GSDM form a regulatory pathway for directing the pit cells to apoptosis.


Asunto(s)
Apoptosis , Proteínas de Unión al ADN/fisiología , Regulación Neoplásica de la Expresión Génica , Proteínas de Neoplasias/genética , Transducción de Señal , Neoplasias Gástricas/genética , Factores de Transcripción/fisiología , Factor de Crecimiento Transformador beta/metabolismo , Secuencia de Bases , Línea Celular Tumoral , Subunidad alfa 3 del Factor de Unión al Sitio Principal/fisiología , Mucosa Gástrica/metabolismo , Humanos , Proteínas con Dominio LIM , Datos de Secuencia Molecular , Regiones Promotoras Genéticas , Sitio de Iniciación de la Transcripción
13.
Neuron ; 19(1): 77-89, 1997 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-9247265

RESUMEN

We identified DN-cadherin, a novel Drosophila cadherin that is expressed in axons and in the mesoderm. Although DN-cadherin has diverged from vertebrate classic cadherins in terms of its extracellular structure, it still can form a complex with catenins and induce cell aggregation, as do the vertebrate molecules. Loss-of-function mutations of the gene resulted in either embryonic lethality or uncoordinated locomotion of adults. In the central nervous system of null mutant embryos, subsets of ipsilateral axons displayed a variety of aberrant trajectories including failure of position shifts, defective bundling, and errors in directional migration of growth cones. These results suggest that processes of axon patterning critically depend on DN-cadherin-mediated axon-axon interactions.


Asunto(s)
Axones/metabolismo , Cadherinas/fisiología , Sistema Nervioso Central/metabolismo , Animales , Secuencia de Bases , Clonación Molecular , Drosophila , Desarrollo Embrionario y Fetal/fisiología , Datos de Secuencia Molecular
14.
Xenobiotica ; 38(9): 1191-202, 2008 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-18609448

RESUMEN

1. Zonampanel, a novel alpha-amino-3-hydroxy-5-methylisoxazole-4-propionate (AMPA) receptor antagonist, is mainly excreted unchanged via renal tubular secretion. The renal apical transport transport of zonampanel was examined in this study using HEK293 cells expressing human organic anion transporter 4 (OAT4/SLC22A11), and membrane vesicles prepared from Sf-9 insect cells expressing human multidrug resistance-associated protein 2 (MRP2/ABCC2), MRP4 (ABCC4), and breast cancer resistance protein (BCRP/ABCG2). 2. Glutaric acid, a model dicarboxylate, trans-stimulated the uptake of [(14)C]zonampanel by OAT4, suggesting that zonampanel was transported by OAT4 via an exchange with dicarboxylate. Considering the endogenous dicarboxylate gradient, OAT4 seems to transport zonampanel in the direction of reabsorption rather than secretion. For MRP2, MRP4, and BCRP, zonampanel selectively inhibited the activity of MRP4 (K(i) = 41.3 microM). Marked transport of [(14)C]zonampanel was observed only for MRP4 (K(m) = 33.7 microM). 3. In conclusion, the data indicate that MRP4 was the apical efflux transporter that contributed to the active renal tubular secretion of zonampanel in humans, in concert with the apical reabsorption transporter OAT4 and basolateral uptake transporters.


Asunto(s)
Transportadoras de Casetes de Unión a ATP/metabolismo , Imidazoles/farmacocinética , Proteínas Asociadas a Resistencia a Múltiples Medicamentos/metabolismo , Proteínas de Neoplasias/metabolismo , Transportadores de Anión Orgánico Sodio-Independiente/metabolismo , Quinoxalinas/farmacocinética , Receptores AMPA/antagonistas & inhibidores , Transportador de Casetes de Unión a ATP, Subfamilia G, Miembro 2 , Animales , Línea Celular , Glutaratos/farmacología , Humanos , Túbulos Renales/metabolismo , Proteína 2 Asociada a Resistencia a Múltiples Medicamentos , Vesículas Transportadoras/efectos de los fármacos
15.
Xenobiotica ; 38(9): 1203-18, 2008 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-18686197

RESUMEN

The inhibitory effects of cationic drugs (beta-adrenoreceptor antagonists, calcium (Ca)-channel blocker, I(f) channel inhibitor, antiarrhythmic drugs, and antibacterial drugs) that inhibit 1-methyl-4-phenylpyridinium (MPP) and/or metformin uptake into hOCT1-3/rOct1-3-expressing cells and human/rat hepatocytes were investigated in this study. The drug-drug interaction (DDI) potential of these drugs for the hOCT/rOct-mediated hepatic/renal uptake process was also assessed. The IC(50) values of cardiovascular drugs, including an I(f) channel inhibitor with a new mechanism of action, were greater for hOCT2/rOct2 than those for hOCT1/rOct1 or hOCT3/rOct3. No species differences in these values were observed between hOCTs and rOcts. As for hOCT2-mediated uptake, the IC(50) values of quinidine and the I(f) channel inhibitor for metformin uptake were lower than those for MPP uptake. However, previous clinical studies found that the IC(50) values of these drugs for hOCT1/rOct1 and hOCT2/rOct2 were much greater than their unbound plasma concentrations, which suggests that the DDIs of these cationic compounds may not be related to hOCT/rOct-mediated hepatic/renal uptake pathways. In addition, investigation of the luminal transporters of cationic compounds in the kidney, as well as the in vitro DDI potential of their inhibitors, is important for the clarification of cationic compound DDIs in humans.


Asunto(s)
Antiarrítmicos/farmacología , Benzamidas/farmacología , Cationes/farmacología , Interacciones Farmacológicas , Isoquinolinas/farmacología , Proteínas de Transporte de Catión Orgánico/efectos de los fármacos , 1-Metil-4-fenilpiridinio/metabolismo , Animales , Antibacterianos/farmacología , Línea Celular , Cimetidina/farmacología , Antagonistas de los Receptores H2 de la Histamina/farmacología , Humanos , Lidocaína/farmacología , Metformina/metabolismo , Proteínas de Transporte de Catión Orgánico/antagonistas & inhibidores , Proteínas de Transporte de Catión Orgánico/metabolismo , Procainamida/farmacología , Quinidina/farmacología , Ratas
16.
Xenobiotica ; 38(10): 1274-88, 2008 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-18800311

RESUMEN

In this study the tissue distribution of radioactivity in pregnant and lactating rats was investigated by quantitatively determining radioactivity concentrations and by whole-body autoradioluminograms after a single oral administration of 14C-YM758. In addition, the transfer of radioactivity into the reproductive tissues, foetus, and milk is discussed in terms of the localization of transporters in syncytiotrophoblast and mammary gland. The radioactivity concentrations in the liver were the highest of all the tissues and organs tested at all the sampling times. The radioactivity in main tissues (liver and kidney), including reproductive tissues (amniotic fluid, placenta, ovary, and uterus), was not retained for a long time, as in the plasma. The tissue/plasma (T/P) ratio of radioactivity in the foetus was below 1.0, which might be due to Mdr1-mediated export of YM758 into blood via the blood-placenta barrier since YM758 is a substrate for hMDR1, not for hBCRP/rBcrp. The T/P ratio of radioactivity in the maternal milk 1 and 4 h after oral administration of 14C-YM758 was 7.2 and 11.0, respectively. To understand better the distribution of new drugs into the reproductive tissues/milk, and to interpret further the results of reproductive safety studies for drug development, the contribution of transporters expressed in the blood-placenta barrier and mammary gland to the drug-transfer into placenta and milk should be considered.


Asunto(s)
Benzamidas/farmacocinética , Feto/metabolismo , Genitales Femeninos/metabolismo , Isoquinolinas/farmacocinética , Lactancia/metabolismo , Leche/química , Preñez/metabolismo , Administración Oral , Líquido Amniótico/metabolismo , Animales , Benzamidas/administración & dosificación , Femenino , Isoquinolinas/administración & dosificación , Riñón/metabolismo , Hígado/metabolismo , Intercambio Materno-Fetal , Placenta/metabolismo , Embarazo , Ratas , Ratas Endogámicas F344 , Distribución Tisular
17.
Urol Int ; 80(3): 332-4, 2008.
Artículo en Inglés | MEDLINE | ID: mdl-18480643

RESUMEN

Renal artery pseudoaneurysm (RAP) is rare, and has been reported after renal biopsy and percutaneous renal surgery. We report a case of RAP after laparoscopic partial nephrectomy for renal cell carcinoma.


Asunto(s)
Aneurisma Falso/etiología , Laparoscopía , Nefrectomía/efectos adversos , Nefrectomía/métodos , Arteria Renal , Humanos , Masculino , Persona de Mediana Edad
18.
Eur J Drug Metab Pharmacokinet ; 33(2): 117-27, 2008.
Artículo en Inglés | MEDLINE | ID: mdl-18777947

RESUMEN

The pharmacokinetics of YM758, a novel funny If current channel (If channel) inhibitor, was investigated after single intravenous (i.v.) and oral dosing to rats and dogs, and partially compared with the results in humans by using liver microsomes. After i.v. administration, the plasma YM758 concentrations decreased, with an elimination half-life (t(1/2)) of 1.14-1.16 h in rats and 1.10-1.30 h in dogs. Total body clearance (CL(tot)) was 5.71-7.27 and 1.75-1.90 L/h/kg in rats and dogs, respectively which was comparable to the hepatic blood flow rate. In dogs, the pharmacokinetic profiles for i.v. bolus administration and continuous infusion did not differ. After oral administration, the levels of YM758 in rat plasma increased more than dose-proportionally, whereas almost linear pharmacokinetics were observed in dogs. Absolute bioavailability was 7.5%-16.6% in rats and 16.1%-22.0% in dogs. The plasma protein binding saturation of YM758 was observed in dogs and humans; this finding is consistent with the result that the major binding protein of YM758 in plasma is alpha1-acid glycoprotein (AGP), in particular in humans. The blood-to-plasma partition coefficient values were 1.36-1.42 in rats, 0.95-1.15 in dogs and 0.71-0.85 in humans. The results of the metabolic study on liver microsomes indicated that the non-linear pharmacokinetics of YM758 observed in rats may be partially due to a first-pass effect in the gastrointestinal tract and the liver.


Asunto(s)
Canales Catiónicos Regulados por Nucleótidos Cíclicos/antagonistas & inhibidores , Tetrahidroisoquinolinas/farmacología , Administración Oral , Animales , Área Bajo la Curva , Células Sanguíneas/metabolismo , Proteínas Sanguíneas/metabolismo , Perros , Humanos , Inyecciones Intravenosas , Masculino , Microsomas Hepáticos/metabolismo , Unión Proteica , Ratas , Ratas Endogámicas F344
19.
Eur J Drug Metab Pharmacokinet ; 33(4): 211-23, 2008.
Artículo en Inglés | MEDLINE | ID: mdl-19230594

RESUMEN

This study was designed to examine the in vitro metabolism of YM758, a novel cardiovascular agent, and to evaluate its potential to cause drug interactions and induction of CYP isozymes. After incubation with pooled human liver microsomes, YM758 was converted to two major metabolites (AS2036313-00, and YM-394111 or YM-394112). The formation of AS2036313-00, and YM-394111 or YM-394112 were mediated by CYP2D6 and CYP3A4, respectively, which was elucidated by using a bank of human liver microsomes and recombinant CYP enzymes in combination with the utilization of typical substrates and inhibitors. The Ki values of YM758 for midazolam, nifedipine, and metoprolol metabolism ranged from 59 to 340 microM, being much higher than the YM758 concentration in human plasma. The formation of AS2036313-00, and YM-394111 or YM-394112 was inhibited by quinidine and ketoconazole with Ki values of 140 and 0.24 microM, respectively, which indicates that YM758 metabolism may be affected by coadministration of strong CYP2D6 and 3A4 inhibitors in vivo, given the clinical plasma concentrations of quinidine and ketoconazole. After human hepatocytes were exposed to 10 microM YM758, microsomal activity and mRNA level for CYP1A2 were not induced while those for CYP3A4 were slightly induced. The tested concentration was much higher than that in human plasma, which suggests that the induction potential of YM758 is also negligible.


Asunto(s)
Benzamidas/farmacología , Fármacos Cardiovasculares/farmacología , Inducción Enzimática/efectos de los fármacos , Isoquinolinas/farmacología , Microsomas Hepáticos/efectos de los fármacos , Benzamidas/metabolismo , Benzamidas/farmacocinética , Fármacos Cardiovasculares/farmacocinética , Citocromo P-450 CYP1A2/efectos de los fármacos , Citocromo P-450 CYP1A2/metabolismo , Citocromo P-450 CYP2D6/efectos de los fármacos , Citocromo P-450 CYP2D6/metabolismo , Citocromo P-450 CYP3A/efectos de los fármacos , Citocromo P-450 CYP3A/metabolismo , Interacciones Farmacológicas , Inhibidores Enzimáticos/farmacología , Femenino , Hepatocitos/efectos de los fármacos , Hepatocitos/enzimología , Humanos , Isoquinolinas/metabolismo , Isoquinolinas/farmacocinética , Masculino , Microsomas Hepáticos/enzimología , Persona de Mediana Edad , ARN Mensajero/efectos de los fármacos , ARN Mensajero/metabolismo
20.
Curr Biol ; 11(11): 859-63, 2001 Jun 05.
Artículo en Inglés | MEDLINE | ID: mdl-11516647

RESUMEN

The Drosophila wing provides an appropriate model system for studying genetic programming of planar cell polarity (PCP) [1-4]. Each wing cell respects the proximodistal (PD) axis; i.e., it localizes an assembly of actin bundles to its distalmost vertex and produces a single prehair. This PD polarization requires the redistribution of Flamingo (Fmi), a seven-pass transmembrane cadherin, to proximal/distal cell boundaries; otherwise, the cell mislocalizes the prehair [5]. Achievement of the biased Fmi pattern depends on two upstream components in the PCP signaling pathway: Frizzled (Fz), a receptor for a hypothetical polarity signal, and an intracellular protein, Dishevelled (Dsh) [6-8]. Here, we visualized endogenous Dsh in the developing wing. A portion of Dsh colocalized with Fmi, and the distributions of both proteins were interdependent. Furthermore, Fz controlled the association of Dsh with cell boundaries, which association was correlated with the presence of hyperphosphorylated forms of Dsh. Our results, together with a recent study on Fz distribution [9], support the possibility that Fz, Dsh, and Fmi constitute a signaling complex and that its restricted localization directs cytoskeletal reorganization only at the distal cell edge.


Asunto(s)
Cadherinas/aislamiento & purificación , Polaridad Celular , Proteínas de Drosophila , Proteínas de Insectos/aislamiento & purificación , Fosfoproteínas/aislamiento & purificación , Alas de Animales/citología , Proteínas Adaptadoras Transductoras de Señales , Animales , Proteínas Dishevelled , Drosophila , Receptores Frizzled , Larva , Proteínas de la Membrana/aislamiento & purificación , Estructura Terciaria de Proteína , Pupa , Receptores Acoplados a Proteínas G , Distribución Tisular
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