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1.
J Plast Reconstr Aesthet Surg ; 74(6): 1239-1245, 2021 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-33288470

RESUMEN

BACKGROUND: Free flap failure secondary to internal jugular vein thrombosis (IJVT) is a significant complication after head and neck reconstructive surgery. A consensus has not yet been reached among reconstructive surgeons regarding the treatment of IJVT. METHODS: We retrospectively evaluated the incidence of IJVT in 118 patients who underwent free flap reconstruction at Hyogo Cancer Center, Akashi, Japan. The occurrence of IJVT-related flap circulation crisis and pulmonary thromboembolism (PTE) was studied. This study was approved by the institutional ethics committee, and written informed consent was obtained from each patient. RESULTS: From 118 patients who underwent head and neck reconstructive surgery, we included 116 internal jugular veins (IJVs) preserved after neck dissection in the present study. IJVT was confirmed in 25 (21.6%) IJVs from 23 patients. One patient (0.8%) developed venous congestion due to IJVT, which resulted in total flap necrosis. Two patients (1.7%) exhibited PTE associated with IJVT. They were treated with direct oral anticoagulants for 3 months and were discharged without any sequelae. CONCLUSION: Our results suggest that IJVT after head and neck reconstructive surgery caused not only flap circulation crisis but also PTE. Reconstructive surgeons should be aware of the potential risks due to serious complications associated with IJVT.


Asunto(s)
Colgajos Tisulares Libres , Venas Yugulares , Disección del Cuello , Procedimientos de Cirugía Plástica , Complicaciones Posoperatorias , Embolia Pulmonar , Trombosis de la Vena , Inhibidores del Factor Xa/administración & dosificación , Femenino , Colgajos Tisulares Libres/efectos adversos , Colgajos Tisulares Libres/irrigación sanguínea , Neoplasias de Cabeza y Cuello/cirugía , Humanos , Incidencia , Japón/epidemiología , Venas Yugulares/diagnóstico por imagen , Venas Yugulares/patología , Masculino , Persona de Mediana Edad , Disección del Cuello/efectos adversos , Disección del Cuello/métodos , Evaluación de Procesos y Resultados en Atención de Salud , Complicaciones Posoperatorias/fisiopatología , Complicaciones Posoperatorias/terapia , Embolia Pulmonar/diagnóstico , Embolia Pulmonar/tratamiento farmacológico , Embolia Pulmonar/etiología , Procedimientos de Cirugía Plástica/efectos adversos , Procedimientos de Cirugía Plástica/métodos , Estudios Retrospectivos , Ajuste de Riesgo/métodos , Trombosis de la Vena/tratamiento farmacológico , Trombosis de la Vena/epidemiología , Trombosis de la Vena/etiología , Trombosis de la Vena/fisiopatología
2.
Phys Rev Lett ; 118(12): 125001, 2017 Mar 24.
Artículo en Inglés | MEDLINE | ID: mdl-28388197

RESUMEN

The resistive interchange mode destabilized by the resonant interaction with the trapped energetic ions is fully suppressed when the injected power of electron cyclotron heating exceeds a certain threshold. It is shown for the first time that the complete stabilization of the energetic-particle-driven mode without relaxing the energetic particle (EP) pressure gradient is possible by reducing the radial width of the eigenmodes δ_{w}, especially when δ_{w} narrows to a small enough value relative to the finite orbit width of EP.

3.
Phys Rev Lett ; 114(15): 155003, 2015 Apr 17.
Artículo en Inglés | MEDLINE | ID: mdl-25933318

RESUMEN

A new bursting m=1/n=1 instability (m,n: poloidal and toroidal mode numbers) with rapid frequency chirping down has been observed for the first time in a helical plasma with intense perpendicular neutral beam injection. This is destabilized in the plasma peripheral region by resonant interaction between helically trapped energetic ions and the resistive interchange mode. A large radial electric field is induced near the edge due to enhanced radial transport of the trapped energetic ions by the mode, and leads to clear change in toroidal plasma flow, suppression of microturbulence, and triggering an improvement of bulk plasma confinement.

4.
Osteoarthritis Cartilage ; 21(3): 514-23, 2013 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-23296253

RESUMEN

OBJECTIVE: Chondrocyte hypertrophy followed by cartilage destruction is a crucial step for osteoarthritis (OA) development, however, the underlying mechanism remains largely unknown. The objectives of this study are to identify the gene that may cause cartilage hypertrophy and to elucidate its role on OA pathogenesis. DESIGN: Gene expression profiles of cartilages from OA patients and normal subjects were examined by microarray analysis. Expression of deiodinases, enzymes for regulation of triiodothyronine (T3) biosynthesis, in human and rat articular cartilage (AC) were examined by real-time quantitative reverse transcriptase-polymerase chain reaction (qRT-PCR). Rat ACs and chondrocytes were treated with T3 to investigate its role on chondrocyte hypertrophy and inflammatory reaction. Cartilage-specific Type II deiodinase (DIO2) transgenic rats were generated using bacterial artificial chromosome harboring the entire rat Col2a1 and human DIO2 gene. An experimental OA model was created in the animal to examine the role of DIO2 on cartilage degeneration. RESULTS: DIO2 is highly expressed in OA patient AC compared to normal control. In rat AC, DIO2 is specifically expressed among deiodinases and dominantly expressed the same as in brown adipose tissue. T3 induces hypertrophic markers in articular chondrocyte and cartilage explant culture, and enhances the effect of IL-1α on induction of cartilage degrading enzymes. Importantly, cartilage-specific DIO2 transgenic rats are more susceptible to knee joint destabilization and develop severe AC destruction. CONCLUSION: Our findings demonstrate that upregulated expression of DIO2 in OA patient cartilage might be responsible for OA pathogenesis by enhancing the chondrocyte hypertrophy and inflammatory response.


Asunto(s)
Cartílago Articular/metabolismo , Condrocitos/metabolismo , Yoduro Peroxidasa/biosíntesis , Osteoartritis de la Rodilla/metabolismo , Animales , Artritis Experimental/metabolismo , Cartílago Articular/efectos de los fármacos , Estudios de Casos y Controles , Condrocitos/efectos de los fármacos , Perfilación de la Expresión Génica , Humanos , Interleucina-1alfa/metabolismo , Yoduro Peroxidasa/efectos de los fármacos , Yoduro Peroxidasa/genética , Ratas , Ratas Transgénicas , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Triyodotironina/farmacología
5.
Oncogene ; 32(10): 1223-32, 2013 Mar 07.
Artículo en Inglés | MEDLINE | ID: mdl-22525270

RESUMEN

Kaposi's sarcoma-associated herpesvirus (KSHV) K13/vFLIP (viral Flice-inhibitory protein) induces transcription of numerous genes through NF-κB activation, including pro-inflammatory cytokines, which contribute to the pathogenesis of Kaposi's sarcoma (KS). In this study, we report that KSHV vFLIP induces the expression of the NF-κB regulatory proteins A20, ABIN-1 and ABIN-3 (A20-binding NF-κB inhibitors) in primary human endothelial cells, and that KS spindle cells express A20 in KS tissue. In reporter assays, A20 strongly impaired vFLIP-induced NF-κB activation in 293T cells, but ABIN-1 and ABIN-3 did not. Mutational analysis established that the C-terminal domain (residues 427-790) is critical for A20 modulation of NF-κB, but the ubiquitin-editing OTU (ovarian tumor) domain is not. In functional assays, A20 inhibited vFLIP-induced expression of the chemokine IP-10, reduced vFLIP-induced cell proliferation and increased IKK1 protein levels. Thus, we demonstrate that A20 negatively regulates NF-κB activation directly induced by KSHV vFLIP. By attenuating excessive and prolonged vFLIP-induced NF-κB activation that could be harmful to KSHV-infected cells, A20 likely has an important role in the pathogenesis of KSHV-associated diseases, in which vFLIP is expressed.


Asunto(s)
Proteínas de Unión al ADN/metabolismo , Herpesvirus Humano 8/metabolismo , Péptidos y Proteínas de Señalización Intracelular/metabolismo , FN-kappa B/antagonistas & inhibidores , Proteínas Nucleares/metabolismo , Sarcoma de Kaposi/virología , Proteínas Virales/metabolismo , Animales , Quimiocina CXCL10/metabolismo , Proteínas de Unión al ADN/biosíntesis , Proteínas de Unión al ADN/genética , Células Endoteliales/citología , Células Endoteliales/metabolismo , Herpesvirus Humano 8/genética , Humanos , Péptidos y Proteínas de Señalización Intracelular/biosíntesis , Péptidos y Proteínas de Señalización Intracelular/genética , Ratones , FN-kappa B/genética , FN-kappa B/metabolismo , Proteínas Nucleares/biosíntesis , Proteínas Nucleares/genética , Proteínas/genética , Proteínas/metabolismo , Sarcoma de Kaposi/genética , Sarcoma de Kaposi/metabolismo , Sarcoma de Kaposi/patología , Transducción Genética , Transfección , Proteína 3 Inducida por el Factor de Necrosis Tumoral alfa , Proteínas Virales/antagonistas & inhibidores , Proteínas Virales/genética
6.
Rev Sci Instrum ; 83(10): 10E513, 2012 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-23127020

RESUMEN

A high speed tangentially viewing vacuum ultraviolet telescope system has been developed in the Large Helical Device (LHD), with the aim of investigating edge MHD activities. The spatial structure of low frequency (~0.75 kHz) MHD activity with poloidal∕toroidal mode numbers of m∕n = 1∕1 has been measured with this diagnostic.

7.
Phys Rev Lett ; 107(11): 115001, 2011 Sep 09.
Artículo en Inglés | MEDLINE | ID: mdl-22026678

RESUMEN

This Letter presents the discovery of macroscale electron temperature fluctuations with a long radial correlation length comparable to the plasma minor radius in a toroidal plasma. Their spatiotemporal structure is characterized by a low frequency of ∼1-3 kHz, ballistic radial propagation, a poloidal or toroidal mode number of m/n=1/1 (or 2/1), and an amplitude of ∼2% at maximum. Nonlinear coupling between the long-range fluctuations and the microscopic fluctuations is identified. A change of the amplitude of the long-range fluctuation is transmitted across the plasma radius at the velocity which is of the order of the drift velocity.

8.
Phys Rev Lett ; 105(14): 145003, 2010 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-21230839

RESUMEN

Reversed-shear Alfvén eigenmodes were observed for the first time in a helical plasma having negative q0'' (the curvature of the safety factor q at the zero shear layer). The frequency is swept downward and upward sequentially via the time variation in the maximum of q. The eigenmodes calculated by ideal MHD theory are consistent with the experimental data. The frequency sweeping is mainly determined by the effects of energetic ions and the bulk pressure gradient. Coupling of reversed-shear Alfvén eigenmodes with energetic ion driven geodesic acoustic modes generates a multitude of frequency-sweeping modes.

9.
Acta Anaesthesiol Scand ; 52(7): 987-90, 2008 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-18477078

RESUMEN

BACKGROUND: The perioperative period is psychologically as well as physically stressful for patients. Although music and sound are known to reduce patients' psychological stress, a few previous studies showed an objective outcome of music. The aim of the present study was to evaluate the relaxing effect of music during epidural anesthesia, using patients' salivary amylase activity. METHODS: Thirty-two American Society of Anesthesiologists (ASA) I or II patients presenting for inguinal hernia repair under epidural anesthesia were randomly assigned to listen to sounds of a soft wind and a twitter (S group) or to have no sounds (N group). Patients' salivary amylase activity was evaluated on arrival to the operating room and at wound closure. RESULTS: Intra-operative music significantly decreased salivary amylase activity at wound closure in the S group and the activity at wound closure of the S group was significantly smaller than that of the N group. CONCLUSION: Intra-operative natural sound significantly decreased salivary amylase activity of patients undergoing inguinal hernia repair under epidural anesthesia.


Asunto(s)
Estimulación Acústica/psicología , Amilasas/metabolismo , Anestesia Epidural/métodos , Hernia Inguinal/cirugía , Cuidados Intraoperatorios/psicología , Saliva/metabolismo , Estimulación Acústica/métodos , Adaptación Psicológica/fisiología , Anciano , Anestésicos Locales/administración & dosificación , Ansiolíticos/administración & dosificación , Presión Sanguínea , Diazepam/administración & dosificación , Femenino , Frecuencia Cardíaca , Hernia Inguinal/psicología , Humanos , Cuidados Intraoperatorios/métodos , Lidocaína/administración & dosificación , Masculino , Persona de Mediana Edad , Monitoreo Intraoperatorio/métodos , Sonido , Estrés Psicológico/etiología , Estrés Psicológico/psicología , Estrés Psicológico/terapia , Viento
10.
Phys Rev Lett ; 100(4): 045003, 2008 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-18352289

RESUMEN

Three states of a magnetic island are observed when the magnetic shear at the rational surface is modified using inductive current associated with the neutral beam current drive in the Large Helical Device. One state is the healed magnetic island with a zero island width. The second state is the saturated magnetic island with partial flattening of the T(e) profile. The third state is characterized by the global flattening of the T(e) profile in the core region. As the plasma assumes each of the three states consecutively through a bifurcation process a clear hysteresis in the relation between the size of the magnetic island and the magnetic shear is observed.

11.
Neuroscience ; 146(1): 123-34, 2007 Apr 25.
Artículo en Inglés | MEDLINE | ID: mdl-17320303

RESUMEN

Ca2+-induced Ca2+ release (CICR) occurs via activation of ryanodine receptors (RyRs) in frog motor nerve terminals after RyRs are primed for activation by repetitive Ca2+ entries, thereby contributing to synaptic plasticity. To clarify how the mechanism of CICR becomes activable by repetitive Ca2+ entries, we studied effects of a RyR modulator, cyclic ADP-ribose (cADPr), on CICR by Ca2+ imaging techniques. Use-dependent binding of fluorescent ryanodine and its blockade by ryanodine revealed the existence of RyRs in the terminals. Repetition of tetani applied to the nerve produced repetitive rises in intracellular Ca2+ ([Ca2+]i) in the terminals. The amplitude of each rise slowly waxed and waned during the course of the stimulation. These slow rises and decays were blocked by ryanodine, indicating the priming, activation and inactivation of CICR. Uncaging of caged-cADPr loaded in the terminals increased the amplitude of short tetanus-induced rises in [Ca2+]i and the amplitude, time to peak and half decay time of the slow waxing and waning rises in [Ca2+]i evoked by repetitive tetani. A cADPr blocker, 8-amino-cADPr, loaded in the terminals decreased the slow waxing and waning component of rises and blocked all the actions of exogenous cADPr. It is concluded that cADPr enhances the priming and activation of CICR. The four-state model for RyRs suggests that cADPr inhibits the inactivation of CICR and increases the activation efficacy of RyR.


Asunto(s)
Calcio/metabolismo , ADP-Ribosa Cíclica/análogos & derivados , Neuronas Motoras/citología , Terminales Presinápticos/efectos de los fármacos , Terminales Presinápticos/metabolismo , Animales , ADP-Ribosa Cíclica/farmacología , Técnicas In Vitro , Neuronas Motoras/efectos de los fármacos , Unión Neuromuscular/citología , Ranidae , Rianodina/metabolismo , Factores de Tiempo
12.
Neuroscience ; 135(2): 395-402, 2005.
Artículo en Inglés | MEDLINE | ID: mdl-16125851

RESUMEN

The dentate gyrus of the hippocampal formation produces new neurons throughout adulthood in mammalian species. Several experimental statuses and factors regulating to neurogenesis have been identified in the adult dentate gyrus. For example, exposure to an enriched environment enhances neurogenesis in the dentate gyrus and improves hippocampus-dependent spatial learning. Furthermore, serotonin is known to influence adult neurogenesis, and learning and memory. However, the effects of long-lasting depletion of serotonin over the developing period on neurogenesis have not been investigated. Thus, we examined the influence of long-lasting serotonin depletion on environmental enrichment-induced neurogenesis and spatial memory performance. As reported previously, environmental enrichment significantly increased new neurons in the dentate gyrus. However, there was no improvement of the spatial learning test in adult rats in standard and in environmental enrichment housings. Intracisternal administration of the serotonergic neurotoxin, 5,7-dihydroxytryptamine, on postnatal day 3 apparently reduced serotonin content in the adult hippocampus without regeneration. This experimental depletion of serotonin in the hippocampus of rats housed in an enriched environment had no effect on spatial memory performance, but produced significant decreases in the number of bromodeoxyuridine-labeled new cells in the dentate gyrus. These findings indicate that newly generated cells stimulated by environmental enrichment are not critical for improvements in hippocampus-dependent learning. Furthermore, numbers of bromodeoxyuridine-labeled cells in the dentate gyrus of 5,7-dihydroxytryptamine-injected rats did not differ between 1 day and 4 weeks after bromodeoxyuridine injection. These data suggest that survival of newly generated dentate gyrus cells remains relatively constant under long-lasting serotonin depletion.


Asunto(s)
Ambiente , Hipocampo/fisiología , Aprendizaje por Laberinto/fisiología , Serotonina/deficiencia , Conducta Espacial/fisiología , 5,7-Dihidroxitriptamina/toxicidad , Análisis de Varianza , Animales , Animales Recién Nacidos , Conducta Animal , Química Encefálica/efectos de los fármacos , Química Encefálica/fisiología , Bromodesoxiuridina/metabolismo , Recuento de Células/métodos , Cromatografía Líquida de Alta Presión/métodos , Desipramina/farmacología , Inhibidores Enzimáticos/farmacología , Femenino , Hipocampo/citología , Ácido Hidroxiindolacético/metabolismo , Inmunohistoquímica/métodos , Masculino , Aprendizaje por Laberinto/efectos de los fármacos , Plasticidad Neuronal , Norepinefrina/metabolismo , Ratas , Ratas Sprague-Dawley , Tiempo de Reacción/efectos de los fármacos , Tiempo de Reacción/fisiología , Serotonina/metabolismo , Serotoninérgicos/toxicidad , Conducta Espacial/efectos de los fármacos , Factores de Tiempo
13.
Phys Rev Lett ; 91(24): 245001, 2003 Dec 12.
Artículo en Inglés | MEDLINE | ID: mdl-14683130

RESUMEN

The helicity-induced Alfvén eigenmodes (HAEs) with the toroidal mode number n=2 and 3 are observed for the first time in the Large Helical Device plasmas heated by neutral beam injection. The observed mode frequency is about 8 times higher than that of the observed toroidicity-induced Alfvén eigenmodes, and is proportional to the Alfvén velocity. The modes are excited when the ratio of the beam velocity to the Alfvén velocity exceeds about unity. The frequency lies just above the lower bound of the HAE gap in the plasma edge region of rho>0.7 (rho: normalized minor radius).

14.
Phys Rev Lett ; 90(20): 205001, 2003 May 23.
Artículo en Inglés | MEDLINE | ID: mdl-12785901

RESUMEN

Sawtooth oscillations have been observed in current-carrying helical plasmas by using electron-cyclotron-emission diagnostics in the Large Helical Device. The plasma current, which is driven by neutral beam injection, reduces the beta threshold of the sawtooth oscillation. When the central q value is increased due to the plasma current, the core region crashes, and, when it is decreased, the edge region crashes annularly. Observed rapid mixture of the plasma in the limited region suggests that these sawtooth crashes are reconnection phenomena. Unlike previous experiments, no precursor oscillation has been observed.

15.
Phys Rev Lett ; 88(5): 055005, 2002 Feb 04.
Artículo en Inglés | MEDLINE | ID: mdl-11863738

RESUMEN

In the Large Helical Device plasma discharges, the size of an externally imposed island with mode number ( n/m = 1/1) decreases substantially when the plasma is collisionless ( nu(*)< approximately 1) and the beta is finite ( > approximately 0.1%) at the island location. For the collisional plasmas with finite beta, on the other hand, the size of the island increases. However, there is a threshold in terms of the vacuum island size below which the island enlargement is not seen.

16.
Biol Reprod ; 66(2): 500-7, 2002 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-11804968

RESUMEN

The Musashi1 (Msi1) gene identified in mouse is a member of a subfamily of RNA binding proteins that are highly conserved across species. Msi1 expression is highly enriched in proliferative cells within the developing central nervous system. Within the testis, proliferation and differentiation of germ cells takes place within the seminiferous epithelium, where these cells are supported physically and functionally by Sertoli cells that do not themselves proliferate following the onset of puberty. RNA binding proteins expressed in testicular germ cells are essential for normal fertility. Preliminary data suggested the mRNA for Msi1 was present in ovary; therefore, we used an Msi1-specific cRNA and monoclonal antibody to investigate whether Msi1 was expressed in the testis. Msi1 mRNA was expressed in rat testis from birth until adulthood; in situ hybridization revealed silver grains within the seminiferous epithelium. Immunohistochemical studies demonstrated that at all ages examined (from Fetal Day 14.5 until adulthood) Msi1 protein was expressed in Sertoli cells. In fetal and adult rat ovaries, Msi1 was detected in granulosa cells and their precursors. In Sertoli cells, protein was detected in both cytoplasmic and nuclear compartments; in adult testes, the immunointensity of the nuclear staining was stage dependent, with highest levels of expression in Sertoli cells at stages I-VI. In rat gonads, the RNA binding protein Msi1 is expressed in both proliferating and nonproliferating Sertoli and granulosa cells.


Asunto(s)
Envejecimiento/metabolismo , Proteínas del Tejido Nervioso/biosíntesis , Proteínas de Unión al ARN/biosíntesis , Células de Sertoli/metabolismo , Testículo/embriología , Testículo/metabolismo , Animales , Northern Blotting , Núcleo Celular/efectos de los fármacos , Núcleo Celular/metabolismo , Citoplasma/efectos de los fármacos , Citoplasma/metabolismo , Etidio/metabolismo , Femenino , Feto/metabolismo , Técnica del Anticuerpo Fluorescente , Células Germinativas/metabolismo , Inmunohistoquímica , Hibridación in Situ , Masculino , Datos de Secuencia Molecular , Folículo Ovárico/metabolismo , ARN Mensajero/biosíntesis , ARN Mensajero/aislamiento & purificación , Ratas , Túbulos Seminíferos/metabolismo , Vimentina/metabolismo
17.
Differentiation ; 68(2-3): 141-52, 2001 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-11686236

RESUMEN

Tumor cells often express phenotypic markers that are specific to the cells from which they originated. A neural RNA-binding protein, Musashil, is an evolutionarily well-conserved marker for neural stem cells/ progenitor cells. To examine the origin of gliomas, we examined the expression of the human Musashil homolog, MSI1, in human glioma tissues and in normal human adult and fetal brains. As we had seen previously in rodents, in the normal human brain, MSI1 was expressed in cells located in the ventricular and subventricular zones, in GFAP-negative glial cells, and in GFAP-positive astrocytes. In glioblastomas, MSI1 was expressed in GFAP-negative tumor cells forming foci that were clearly demarcated and surrounded by GFAP-positive cells. Tumor cells arranged in pseudopalisades were also strongly immunoreactive with MSI1 antibodies. The percentage of MSI1-labeled tumor cells increased in higher-grade astrocytomas and correlated with proliferative activity, as estimated by an MIB-1 staining index. Our results indicate that MSI1 is an excellent marker for neural progenitor cells including neural stem cells in normal human brains. Furthermore, the expression of MSI1 correlates well with the immature nature as well as the malignancy of tumor cells in human gliomas. Thus, we expect the analysis of MSI1 expression to contribute to the understanding of the cellular origin and biology of human gliomas.


Asunto(s)
Biomarcadores de Tumor/metabolismo , Neoplasias del Sistema Nervioso Central/metabolismo , Neoplasias del Sistema Nervioso Central/patología , Glioma/metabolismo , Glioma/patología , Proteínas del Tejido Nervioso/metabolismo , Proteínas de Unión al ARN/metabolismo , Receptores de Superficie Celular , Factores de Transcripción , Adulto , Anciano , Biomarcadores de Tumor/inmunología , Encéfalo/embriología , Encéfalo/metabolismo , División Celular/fisiología , Evolución Molecular , Femenino , Humanos , Immunoblotting , Masculino , Proteínas de la Membrana/metabolismo , Persona de Mediana Edad , Proteínas del Tejido Nervioso/inmunología , Proteínas de Unión al ARN/inmunología , Receptor Notch1 , Valores de Referencia , Transducción de Señal
18.
Phys Rev Lett ; 87(13): 135002, 2001 Sep 24.
Artículo en Inglés | MEDLINE | ID: mdl-11580597

RESUMEN

It was observed that the vacuum magnetic island produced by an external error magnetic field in the large helical device shrank in the presence of plasma. This was evidenced by the disappearance of flat regions in the electron temperature profile obtained by Thomson scattering. This island behavior depended on the magnetic configuration in which the plasmas were produced.

19.
Chem Pharm Bull (Tokyo) ; 49(10): 1261-6, 2001 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-11605651

RESUMEN

The objectives of this study were to prepare insulin-loaded acrylic hydrogel formulations containing various absorption enhancers, to perform in vitro and in vivo characterization of these formulations, and to evaluate the factors which affecting insulin availability on rectal delivery of insulin using this hydrogel system. The acrylic block copolymer of methacrylic acid and methacrylate, Eudispert, was used to make the hydrogel formulations. As absorption enhancers, 2,6-di-O-methyl-beta-cyclodextrin (DM-beta-CyD), lauric acid (C12), or the sodium salt of C12 (C12Na), were incorporated into the hydrogels. In an in vitro release test, the release rate of insulin from the hydrogels decreased as the polymer concentration of the hydrogel increased. The addition of C12Na to the hydrogel further increased the insulin release rate, which was greater at higher concentrations of the enhancer. A portion of the C12Na was found to remain bound to the acrylic polymer in dissolution medium. Serum insulin levels were determined at various time points after the administration of insulin solution or insulin-loaded (50 units/kg body weight) Eudispert hydrogels containing 5% (w/w) of C12, C12Na, or DM-beta-CyD to in situ loops in various regions of the rat intestine. The most effective enhancement of insulin release was observed with formulations containing C12Na. The bioavailability of insulin from the hydrogels was lower than that from the insulin solutions. Hydrogel formulations containing 7% or 10% Eudispert remained in the rectum for 5 h after rectal administration. However, the 5% (w/w) C12Na solution stained with Evan's-blue had diffused out and the dye had reached the upper intestinal tract within 2 h. Finally, the rectal administration of insulin-loaded hydrogels, containing 4%, 7%, or 10% (w/w) Eudispert and 5% (w/w) of enhancer (C12, C12Na, or DM-beta-CyD) to normal rats was shown to decrease serum glucose concentrations. The greatest effect was found with insulin-loaded 7% (Eudispert) hydrogel containing C12Na which having cosiderable large insulin release rate and bioadhesive characteristics.


Asunto(s)
Excipientes , Hipoglucemiantes/administración & dosificación , Hipoglucemiantes/farmacología , Insulina/administración & dosificación , Insulina/farmacología , Absorción Intestinal/efectos de los fármacos , Acrilatos , Administración Rectal , Animales , Glucemia/metabolismo , Hidrogeles , Hipoglucemiantes/farmacocinética , Insulina/farmacocinética , Mucosa Intestinal/metabolismo , Masculino , Ácidos Polimetacrílicos , Ratas , Ratas Wistar
20.
J Neurosci ; 21(20): 8091-107, 2001 Oct 15.
Artículo en Inglés | MEDLINE | ID: mdl-11588182

RESUMEN

Musashi1 (Msi1) is a mammalian neural RNA-binding protein highly enriched in neural precursor cells that are capable of generating both neurons and glia during embryonic and postnatal CNS development. Here, we identified Musashi2 (Msi2), a novel mammalian RNA-binding protein that exhibits high sequence similarity to Msi1. The Msi2 transcript appeared to be distributed ubiquitously in a wide variety of tissues, consistent with the mRNA distribution of its Xenopus homolog, xrp1. However, the present study revealed cell type-specific and developmentally regulated expression of Msi2 in the mammalian CNS. Interestingly, Msi2 was expressed prominently in precursor cells in the ventricular zone and subventricular zone with the same pattern as Msi1 throughout CNS development. In the postnatal and adult CNS, this concurrent expression of Msi2 and Msi1 was seen in cells of the astrocyte lineage, including ependymal cells, a possible source for postnatal CNS stem cells. During neurogenesis, the expression of both Msi2 and Msi1 was lost in most postmitotic neurons, whereas Msi2 expression persisted in a subset of neuronal lineage cells, such as parvalbumin-containing GABA neurons in the neocortex and neurons in several nuclei of the basal ganglia. Msi2 may have a unique role that is required for the generation and/or maintenance of specific neuronal lineages. Furthermore, in vitro studies showed that Msi2 and Msi1 have similar RNA-binding specificity. These two RNA-binding proteins may exert common functions in neural precursor cells by regulating gene expression at the post-transcriptional level.


Asunto(s)
Sistema Nervioso Central/metabolismo , Regulación del Desarrollo de la Expresión Génica , Neuronas/metabolismo , Proteínas de Unión al ARN/metabolismo , Células Madre/metabolismo , Proteínas de Xenopus , Empalme Alternativo/genética , Animales , Sistema Nervioso Central/citología , Clonación Molecular , ADN Complementario/genética , ADN Complementario/aislamiento & purificación , Hibridación Fluorescente in Situ , Ratones , Ratones Endogámicos C57BL , Ratones Endogámicos ICR , Datos de Secuencia Molecular , Proteínas del Tejido Nervioso/genética , Neuronas/citología , Especificidad de Órganos , Mapeo Físico de Cromosoma , Isoformas de Proteínas/genética , ARN Mensajero/metabolismo , Proteínas de Unión al ARN/genética , Ribonucleoproteínas , Análisis de Secuencia de ADN , Células Madre/citología
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