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1.
AJNR Am J Neuroradiol ; 43(12): 1713-1718, 2022 12.
Artículo en Inglés | MEDLINE | ID: mdl-36265890

RESUMEN

BACKGROUND AND PURPOSE: High-resolution vessel wall MR imaging is prone to slow-flow artifacts, particularly when gadolinium shortens the T1 relaxation time of blood. This study aimed to determine the optimal preparation pulses for contrast-enhanced high-resolution vessel wall MR imaging. MATERIALS AND METHODS: Fifty patients who underwent both motion-sensitized driven equilibrium and delay alternating with nutation for tailored excitation (DANTE) preparation pulses with contrast-enhanced 3D-T1-FSE were retrospectively included. Qualitative analysis was performed using a 4-grade visual scoring system for black-blood performance in the small-sized intracranial vessels, overall image quality, severity of artifacts, and the degree of blood suppression in all cortical veins as well as transverse sinuses. Quantitative analysis of the M1 segment of the MCA was also performed. RESULTS: The qualitative analysis revealed that motion-sensitized driven equilibrium demonstrated a significantly higher black-blood score than DANTE in contrast-enhanced 3D-T1-FSE of the A3 segment (3.90 versus 3.58, P < .001); M3 (3.72 versus 3.26, P = .004); P2 to P3 (3.86 versus 3.64, P = .017); the internal cerebral vein (3.72 versus 2.32, P < .001); and overall cortical veins (3.30 versus 2.74, P < .001); and transverse sinuses (2.82 versus 2.38, P < .001). SNRlumen, contrast-to noise ratiowall-lumen, and SNRwall in the M1 vessel were not significantly different between the 2 preparation pulses (all, P > .05). CONCLUSIONS: Motion-sensitized driven equilibrium demonstrated improved blood suppression on contrast-enhanced 3D-T1-FSE in the small intracranial arteries and veins compared with DANTE. Motion-sensitized driven equilibrium is a useful preparation pulse for high-resolution vessel wall MR imaging to decrease venous contamination and suppress slow-flow artifacts when using contrast enhancement.


Asunto(s)
Venas Cerebrales , Angiografía por Resonancia Magnética , Humanos , Angiografía por Resonancia Magnética/métodos , Estudios Retrospectivos , Relación Señal-Ruido , Imagen por Resonancia Magnética/métodos , Encéfalo/irrigación sanguínea , Venas Cerebrales/diagnóstico por imagen , Imagenología Tridimensional
2.
BMC Anesthesiol ; 18(1): 181, 2018 12 03.
Artículo en Inglés | MEDLINE | ID: mdl-30509183

RESUMEN

BACKGROUND: Microaspiration past the tracheal tube cuffs causes ventilator-associated pneumonia. The objective of the current study was to evaluate whether creating negative pressure between the tracheal double cuffs could block the fluid passage past the tracheal tube cuffs. METHODS: A new negative pressure system was devised between the double cuffs through a suction hole in the intercuff space. Blue-dyed water was instilled above the cuff at negative suction pressures of - 54, - 68, - 82, - 95, - 109, - 122, and - 136 cmH2O, and the volume leaked was measured in an underlying water trap after 10 min. Leakage tests were also performed during positive pressure ventilation, and using higher-viscosity materials. The actual negative pressures delivered at the hole of double cuffs were obtained by placing microcatheter tip between the intercuff space and the artificial trachea. RESULTS: No leakage occurred past the double cuff at - 136 cmH2O suction pressure at all tracheal tube cuff pressures. The volume leaked decreased significantly as suction pressure increased. When connected to a mechanical ventilator, no leakage was found at - 54 cmH2suction pressure. Volume of the higher-viscosity materials (dynamic viscosity of 63-108 cP and 370-430 cP) leaked was small compared to that of normal saline (0.9-1.1 cP). The pressures measured in the intercuff space corresponded to 3.8-5.9% of those applied. CONCLUSIONS: A new prototype double cuff with negative pressure in the intercuff space completely prevented water leakage. The negative pressure transmitted to the tracheal inner wall was a small percentage of that applied.


Asunto(s)
Diseño de Equipo/instrumentación , Intubación Intratraqueal/instrumentación , Respiración con Presión Positiva/instrumentación , Aspiración Respiratoria/prevención & control , Ventiladores de Presión Negativa , Diseño de Equipo/métodos , Humanos , Intubación Intratraqueal/métodos , Respiración con Presión Positiva/métodos , Presión
3.
Transplant Proc ; 48(1): 102-6, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-26915851

RESUMEN

BACKGROUND: Concerns about the adverse effects of hydroxyethyl starch (HES) on renal function have been raised in recent studies involving critically ill patients. We aimed to evaluate the effect of HES on acute kidney injury (AKI) after living donor right hepatectomy. METHODS: We performed a 1:3 propensity score matching analysis of the medical records of 1641 living donors who underwent a donor right hepatectomy. They were divided into the control group (n = 60), who received only crystalloids, and the colloid group (n = 1,581), who received HES 130/0.4 and crystalloids. Postoperative AKI was determined by AKI Network (AKIN) and Risk, Injury, Failure, Loss, End-stage (RIFLE) criteria. RESULTS: A 1:3 propensity score matching was performed in 206 donors, 54 donors in the control group and 152 donors in the colloid group. For the matched colloid group, the median amount of 7.65 mL/kg (interquartile range, 6.64-9.20) of colloid and 58.19 mL/kg (interquartile range, 45.63-71.51) of crystalloid were given. The median amount of administered crystalloid in the control group was 56.48 mL/kg (interquartile range, 47.94-76.12) after propensity score matching. The incidences of AKI were not different between the control and colloid groups (P = .460 by AKIN criteria; P = .999 by RIFLE criteria). CONCLUSION: Intraoperative administration of HES may not be associated with AKI after living donor hepatectomy. This result can provide useful information on perioperative fluid management in living liver donors.


Asunto(s)
Lesión Renal Aguda/inducido químicamente , Hepatectomía/métodos , Derivados de Hidroxietil Almidón/efectos adversos , Donadores Vivos , Sustitutos del Plasma/efectos adversos , Recolección de Tejidos y Órganos/métodos , Lesión Renal Aguda/epidemiología , Adulto , Anciano , Estudios de Casos y Controles , Soluciones Cristaloides , Femenino , Fluidoterapia/efectos adversos , Humanos , Incidencia , Soluciones Isotónicas/efectos adversos , Trasplante de Hígado/métodos , Masculino , Persona de Mediana Edad , Periodo Posoperatorio , Puntaje de Propensión
4.
Mol Oral Microbiol ; 29(5): 208-18, 2014 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-24848678

RESUMEN

Streptococcus mutans is a representative oral pathogen that causes dental caries and pulpal inflammation. Its lipoteichoic acid (Sm.LTA) is known to be an important cell-wall virulence factor involved in bacterial adhesion and induction of inflammation. Since Sm.LTA-binding proteins (Sm.LTA-BPs) might play an important role in pathogenesis and host immunity, we identified the Sm.LTA-BPs in the saliva of caries-free and caries-positive human subjects using Sm.LTA-conjugated beads and LTQ-Orbitrap hybrid Fourier transform mass spectrometry. Sm.LTA was conjugated to N-hydroxysuccinimidyl-Sepharose(®) 4 Fast Flow beads (Sm.LTA-beads). Sm.LTA retained its biological properties during conjugation, as determined by the expression of nitric oxide and interferon-γ-inducible protein 10 in a murine macrophage cell line and activation of Toll-like receptor 2 (TLR2) in CHO/CD14/TLR2 cells. Sm.LTA-BPs were isolated from pooled saliva prepared from 10 caries-free or caries-positive human subjects each, electrophoresed to see their differential expression in each group, and further identified by high-resolution mass spectrometry. A total of 8 and 12 Sm.LTA-BPs were identified with statistical significance in the pooled saliva from the caries-free and caries-positive human subjects, respectively. Unique Sm.LTA-BPs found in caries-free saliva included histone H4, profilin-1 and neutrophil defensin-1, and those in caries-positive saliva included cystatin-C, cystatin-SN, cystatin-S, cystatin-D, lysozyme C, calmodulin-like protein 3 and ß-actin. The Sm.LTA-BPs found in both groups were hemoglobin subunits α and ß, prolactin-inducible protein, protein S100-A9, and SPLUNC2. Collectively, we identified Sm.LTA-BPs in the saliva of caries-free and caries-positive subjects, which exhibit differential protein profiles.


Asunto(s)
Caries Dental/metabolismo , Lipopolisacáridos/metabolismo , Proteínas y Péptidos Salivales/análisis , Streptococcus mutans/metabolismo , Ácidos Teicoicos/metabolismo , Actinas/análisis , Animales , Adhesión Bacteriana/fisiología , Células CHO , Calmodulina/análisis , Línea Celular , Quimiocina CXCL10/efectos de los fármacos , Cricetulus , Cistatina C/análisis , Cistatinas/análisis , Defensinas/análisis , Caries Dental/microbiología , Histonas/análisis , Humanos , Receptores de Lipopolisacáridos/efectos de los fármacos , Macrófagos/efectos de los fármacos , Ratones , Muramidasa/análisis , Óxido Nítrico/metabolismo , Profilinas/análisis , Cistatinas Salivales/análisis , Proteínas y Péptidos Salivales/metabolismo , Receptor Toll-Like 2/efectos de los fármacos , Factores de Virulencia/metabolismo
5.
Minerva Anestesiol ; 80(2): 185-93, 2014 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-24193176

RESUMEN

BACKGROUND: The oblique subcostal transversus abdominis plane (OSTAP) block has been described as an effective analgesic method for upper abdominal surgery. We evaluated the postoperative analgesia of the OSTAP block and compared it with that of the transversus abdominis plane (TAP) block in patients undergoing laparoscopic cholecystectomy (LC). METHODS: Patients scheduled for elective LC were randomized to receive either standard care or to undergo an OSTAP or TAP block. All blocks were performed with ultrasound guidance, and 20 mL of 0.375% ropivacaine was injected bilaterally. The postoperative pain score and consumption of rescue analgesics were evaluated. RESULTS: The OSTAP block reduced postoperative verbal numerical rating scale pain scores (median [Interquartile range, IQR]) compared to standard care at 10 min (2 [1-4] vs. 7 [5-8]), 30 min (2 [1-5] vs. 6 [5-8]), 1 h (2 [1-3] vs. 5 [4-6]), and 3 h (2 [2-3] vs. 4 [3-5]). Pain scores were also lower in the OSTAP group than in the TAP group at 10 min (2 [1-4] vs. 4 [2-6]), 1 h (2 [1-3] vs. 3 [3-4]), 3 h (2 [2-3] vs. 3 [3-4]), 6 h (2 [2-3] vs. 3 [3-5]), and 24 h (1 [1-2] vs. 2 [2-3]) postoperatively. The total fentanyl requirement was reduced in the OSTAP group (p = 0.005). CONCLUSION: The OSTAP block can provide better analgesia than the TAP block or standard care during the postoperative 24 h period in patients undergoing LC.


Asunto(s)
Músculos Abdominales , Colecistectomía Laparoscópica/métodos , Bloqueo Nervioso/métodos , Dolor Postoperatorio/tratamiento farmacológico , Ultrasonografía Intervencional/métodos , Adulto , Analgésicos/administración & dosificación , Analgésicos/uso terapéutico , Método Doble Ciego , Femenino , Humanos , Masculino , Persona de Mediana Edad
6.
Cell Death Differ ; 20(8): 1055-67, 2013 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-23645206

RESUMEN

ZNF313 encoding a zinc-binding protein is located at chromosome 20q13.13, which exhibits a frequent genomic amplification in multiple human cancers. However, the biological function of ZNF313 remains largely undefined. Here we report that ZNF313 is an ubiquitin E3 ligase that has a critical role in the regulation of cell cycle progression, differentiation and senescence. In this study, ZNF313 is initially identified as a XIAP-associated factor 1 (XAF1)-interacting protein, which upregulates the stability and proapoptotic effect of XAF1. Intriguingly, we found that ZNF313 activates cell cycle progression and suppresses cellular senescence through the RING domain-mediated degradation of p21(WAF1). ZNF313 ubiquitinates p21(WAF1) and also destabilizes p27(KIP1) and p57(KIP2), three members of the CDK-interacting protein (CIP)/kinase inhibitor protein (KIP) family of cyclin-dependent kinase inhibitors, whereas it does not affect the stability of the inhibitor of CDK (INK4) family members, such as p16(INK4A) and p15(INK4B). ZNF313 expression is tightly controlled during the cell cycle and its elevation at the late G1 phase is crucial for the G1-to-S phase transition. ZNF313 is induced by mitogenic growth factors and its blockade profoundly delays cell cycle progression and accelerates p21(WAF1)-mediated senescence. Both replicative and stress-induced senescence are accompanied with ZNF313 reduction. ZNF313 is downregulated during cellular differentiation process in vitro and in vivo, while it is commonly upregulated in many types of cancer cells. ZNF313 shows both the nuclear and cytoplasmic localization in epithelial cells of normal tissues, but exhibits an intense cytoplasmic distribution in carcinoma cells of tumor tissues. Collectively, ZNF313 is a novel E3 ligase for p21(WAF1), whose alteration might be implicated in the pathogenesis of several human diseases, including cancers.


Asunto(s)
Proteínas Portadoras/fisiología , Puntos de Control del Ciclo Celular/fisiología , Senescencia Celular/fisiología , Inhibidor p21 de las Quinasas Dependientes de la Ciclina/fisiología , Factores de Transcripción/fisiología , Ubiquitina-Proteína Ligasas/fisiología , Proteínas Adaptadoras Transductoras de Señales , Animales , Apoptosis/fisiología , Proteínas Reguladoras de la Apoptosis , Ciclo Celular/fisiología , Diferenciación Celular/fisiología , Línea Celular , Línea Celular Tumoral , Proteínas F-Box/fisiología , Xenoinjertos , Humanos , Técnicas In Vitro , Péptidos y Proteínas de Señalización Intracelular/fisiología , Masculino , Ratones , Ratones Desnudos , Modelos Animales , Proteínas de Neoplasias/fisiología
7.
Mol Oral Microbiol ; 28(2): 142-53, 2013 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-23194029

RESUMEN

Aggregatibacter actinomycetemcomitans lipopolysaccharide (Aa.LPS) is a major virulence factor associated with aggressive periodontitis. Although the recognition of Aa.LPS is potentially initiated by salivary proteins in the oral cavity, Aa.LPS-binding proteins (Aa.LPS-BPs) in saliva are poorly characterized. The purpose of this study was to capture and identify Aa.LPS-BPs in human saliva using a LTQ-Orbitrap hybrid Fourier transform mass spectrometry. Aa.LPS conjugated onto N-hydroxysuccinimidyl-Sepharose(®) 4 Fast Flow beads (Aa.LPS-beads) activated Toll-like receptor 4 and produced nitric oxide and Interferon gamma-inducible protein-10, implying that the conjugation process did not alter the biological properties of Aa.LPS. Aa.LPS-BPs were subsequently isolated from the nine human saliva samples from healthy individuals with the Aa.LPS-beads followed by identification with the mass spectrometry. Aa.LPS-BPs include α-amylase, serum albumin, cystatin, lysozyme C, submaxillary gland androgen-regulated protein 3B, immunoglobulin subunits, polymeric immunoglobulin receptor, deleted in malignant brain tumors 1, prolactin-inducible protein, lipocalin-1, and basic salivary proline-rich protein 2. Specific binding was validated using a pull-down assay with α-amylase which was captured at the highest frequency. Alpha-amylase demonstrated to interfere with the adherence and biofilm formation of A. actinomycetemcomitans. Even heat-inactivated α-amylase showed the interference to the same extent. Conclusively, we identified unique Aa.LPS-BPs that provide useful information to understand bacterial pathogenesis and host innate immunity in the oral cavity.


Asunto(s)
Proteínas de Fase Aguda/fisiología , Aggregatibacter actinomycetemcomitans/metabolismo , Proteínas Portadoras/fisiología , Lipopolisacáridos/metabolismo , Glicoproteínas de Membrana/fisiología , Proteínas y Péptidos Salivales/fisiología , alfa-Amilasas/fisiología , Proteínas de Fase Aguda/farmacología , Aggregatibacter actinomycetemcomitans/efectos de los fármacos , Animales , Adhesión Bacteriana/fisiología , Biopelículas/efectos de los fármacos , Proteínas de Unión al Calcio , Proteínas Portadoras/análisis , Proteínas Portadoras/farmacología , Línea Celular , Proteínas de Unión al ADN , Glicoproteínas/análisis , Humanos , Cadenas Pesadas de Inmunoglobulina/análisis , Cadenas Ligeras de Inmunoglobulina/análisis , Mediadores de Inflamación/análisis , Lipocalina 1/análisis , Lipopolisacáridos/fisiología , Macrófagos/efectos de los fármacos , Glicoproteínas de Membrana/farmacología , Proteínas de Transporte de Membrana , Ratones , Muramidasa/análisis , Receptores de Superficie Celular/análisis , Receptores de Inmunoglobulina Polimérica/análisis , Cistatinas Salivales/análisis , Proteínas Salivales Ricas en Prolina/análisis , Proteínas y Péptidos Salivales/análisis , Proteínas y Péptidos Salivales/farmacología , Albúmina Sérica/análisis , Espectroscopía Infrarroja por Transformada de Fourier , Receptor Toll-Like 4/efectos de los fármacos , Proteínas Supresoras de Tumor , Factores de Virulencia/metabolismo , alfa-Amilasas/farmacología
8.
J Nanosci Nanotechnol ; 11(5): 4328-32, 2011 May.
Artículo en Inglés | MEDLINE | ID: mdl-21780451

RESUMEN

In-situ synchrotron radiation photoemission spectroscopy and X-ray photoemission spectroscopy have been used to investigate the initial stages of Al2O3 growth on a Si(001) substrate by atomic layer deposition (ALD). The core level spectra of Si 2p, O 1s, and Al 2p as well as the valence band spectra were measured at every half reaction in the trimethylaluminum (TMA)-H2O ALD process. The line shape changes and binding energy shifts of the core level spectra reveal that Al2O3 is predominantly formed with a small amount of Si oxide in the initial stages without the formation of Al silicate. All core level spectra were alternately shifted toward higher and lower binding energies sides at every half ALD reaction. This can be explained by the band bending effect induced by different chemical species on the surface during the TMA-H2O ALD reaction. The valence band spectra showed that four cycles of ALD reactions were necessary to complete the electronic structure of the Al2O3 film with a valence band offset of 3.73 eV.

10.
Interv Neuroradiol ; 11(1): 69-73, 2005 Mar 17.
Artículo en Inglés | MEDLINE | ID: mdl-20584438

RESUMEN

SUMMARY: We demonstrate endovascular stent deployment for the treatment of atherosclerotic basilar artery occlusion with acute thrombosis. Application of a microstent without previous balloon dilatation resulted in vessel reopening and good clinical improvement. Emergency primary stent application can be technically feasible and improve the outcome in acute basilar artery occlusion and clinical status.

11.
Chem Biol ; 8(9): 857-70, 2001 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-11564554

RESUMEN

BACKGROUND: Melanocortin, through its distinct receptor subtypes, has many different effects. Receptor-selective ligands are required to reduce the undesirable effects of melanocortin. To investigate which conformation is preferable to a given melanocortin receptor subtype, a structural and functional analysis of the ligand-receptor interactions was made by studying the biological activity, the nuclear magnetic resonance structures, and the patterns of the ligand-receptor interaction for each receptor subtype by homology modeling analysis. RESULTS: Among the several analogues examined, [Gln(6)]alpha-melanocyte-stimulating hormone (MSH)-ND was found to have 10000 times less biological activity than alpha-MSH-ND for the MC1R, whereas, the potencies of both oligopeptides were comparable in both the melanocortin-3 receptor (MC3R) and MC4R. [Gln(6)]alpha-MSH-ND exhibited a type I' beta-turn that was similar to the type I beta-turn structure of alpha-MSH-ND. However, a remarkable structural difference was observed with respect to the side chain orientations of the sixth and seventh residues of [Gln(6)]alpha-MSH-ND, which were found to be mirror images of alpha-MSH-ND. By homology modeling analysis, the His(6) of alpha-MSH-ND was found to interact with the TM2 regions of all three receptors (Glu(94) of MC1R, Glu(94) of MC3R, and Glu(100) of MC4R), but [Gln(6)]alpha-MSH-ND did not. The phenyl ring of the D-Phe(7) residue of [Gln(6)]alpha-MSH-ND revealed an interaction with the TM3 regions of both the MC3R and MC4R (Ser(122) of MC3R or Ser(127) of MC4R). However, in the MC1R, these serine residues corresponded to Val(122), which contains two methyl groups that induce steric hindrance with D-Phe(7) of [Gln(6)]alpha-MSH-ND. This is a possible explanation for the biological activity of [Gln(6)]alpha-MSH-ND for the MC1R being significantly lower than that for either the MC3R or MC4R. CONCLUSIONS: Minimization of the MC1R selectivity whilst preserving its comparable potency for both the MC3R and MC4R could be achieved by modifying the D-Phe(7) orientation of alpha-MSH-ND, while maintaining the 'type I beta-turn'-like structure.


Asunto(s)
Receptores de Corticotropina/química , alfa-MSH/análogos & derivados , Animales , Células CHO , Cricetinae , AMP Cíclico/análisis , AMP Cíclico/biosíntesis , Cinética , Ligandos , Espectroscopía de Resonancia Magnética , Modelos Moleculares , Conformación Proteica , Receptores de Corticotropina/metabolismo , Receptores de Melanocortina , Relación Estructura-Actividad , Especificidad por Sustrato , alfa-MSH/metabolismo , alfa-MSH/farmacología
12.
J Neurosci Res ; 64(4): 355-63, 2001 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-11340642

RESUMEN

Neuroblastomas are heterogeneous tumors arising from sympathetic precursors in the neural crest. Growth factor stimulation of neuroblastomas promote diverse biological responses (mitogenesis, differentiation, cell death) depending on the particular tumor studied. Here we show that brief treatment with retinoic acid (RA) rendered the human neuroblastoma lines SY5Y, NGP, SMS-KCNR, and SK-N-SH dependent on brain-derived neurotrophic factor (BDNF) for survival. The BDNF- and trkB-expressing line SMS-KCN was dependent on an autocrine BDNF/trkB survival without exposure to RA. We conclude that the BDNF/trkB pathway plays an important role in neuroblastoma survival and speculate on a possible role in tumor pathogenesis.


Asunto(s)
Apoptosis/fisiología , Factor Neurotrófico Derivado del Encéfalo/metabolismo , Mutación/fisiología , Neuroblastoma/metabolismo , Receptor trkB/metabolismo , Anticuerpos/farmacología , Antineoplásicos/farmacología , Apoptosis/efectos de los fármacos , Factor Neurotrófico Derivado del Encéfalo/efectos de los fármacos , Factor Neurotrófico Derivado del Encéfalo/inmunología , Relación Dosis-Respuesta a Droga , Humanos , Etiquetado Corte-Fin in Situ , Mutación/efectos de los fármacos , Neuroblastoma/patología , Receptor trkB/efectos de los fármacos , Tretinoina/farmacología , Células Tumorales Cultivadas/efectos de los fármacos
13.
Biochem Biophys Res Commun ; 281(2): 499-505, 2001 Feb 23.
Artículo en Inglés | MEDLINE | ID: mdl-11181075

RESUMEN

Tumor necrosis factor (TNF) signaling leads to pleiotropic responses in a wide range of cell types, in part by activating antiapoptotic and proapoptotic pathways. Previous studies have suggested that TNF receptor-associated factor (TRAF) 2 can mediate crucial antiapoptotic signals during TNF stimulation. However, it is unclear how the antiapoptotic signals via TRAF2 in TNF-R1 signaling is regulated. Here we show that TRAF1 is cleaved by caspase-8 into two fragments during apoptosis induced by TNF. Overexpression of the C-terminal cleavage product, TRAF1-c, increased TNF-induced cell death of hybridoma T cells. Importantly, we demonstrate that the cleavage product of TRAF1 coimmunoprecipitates with TRAF2 that is released from the TNF-R1 complex in response to prolonged TNF treatment. These results indicate that caspase-dependent cleavage of TRAF1 generates TRAF1-c fragments that are able to bind TRAF2, and then sequester TRAF2 from the TNF-R1 complex, rendering cells, at least in part, sensitive to TNF.


Asunto(s)
Apoptosis/fisiología , Caspasas/metabolismo , Muerte Celular/efectos de los fármacos , Proteínas/metabolismo , Factor de Necrosis Tumoral alfa/farmacología , Animales , Apoptosis/efectos de los fármacos , Sitios de Unión , Línea Celular , ADN Recombinante , Relación Dosis-Respuesta a Droga , Humanos , Plásmidos/genética , Unión Proteica/efectos de los fármacos , Proteínas/genética , Receptores del Factor de Necrosis Tumoral/genética , Receptores del Factor de Necrosis Tumoral/metabolismo , Transducción de Señal/fisiología , Linfocitos T/citología , Linfocitos T/efectos de los fármacos , Linfocitos T/metabolismo , Factor 1 Asociado a Receptor de TNF , Factor 2 Asociado a Receptor de TNF
14.
Eur J Biochem ; 268(3): 582-91, 2001 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-11168397

RESUMEN

Melanocortins are known to be involved in the regulation of feeding behavior. These hormones mediate their effects through G-protein-coupled receptors by stimulating adenylate cyclase. In this study we describe the functional response of melanocortin 4 receptor (MC4R) and melanocortin 3 receptor (MC3R) in HEK 293T cells, by using a luciferase reporter gene under the transcriptional control of a cAMP-responsive element (CRE) as a monitor of intracellular cAMP levels and cAMP-regulated gene expression. We were able to show that MC4R and MC3R expressed in the human cell line HEK 293T stimulate transcription induced by stimulation with different analogs of alpha-melanocyte-stimulating hormone (alpha-MSH) at different levels. In our assay of CRE-mediated gene transcription activity, alpha-MSH-ND was the most efficient alpha-MSH analog for MC4R whereas NDP-MSH was the most efficient for MC3R. Changing the His6 residue of alpha-MSH-ND to Gln or Lys markedly decreased CRE-mediated luciferase activity for MC3R compared with MC4R. On analysis by modeling the receptor-ligand complex by NMR, [Gln6]alpha-MSH-ND and [Lys6]alpha-MSH-ND showed different conformational interactions between MC3R and MC4R. Furthermore, the maximum coupling efficiency of MC4R and MC3R to G proteins was different; MC4R showed only 30-50% of the maximum activity induced by MC3R. In total, our results suggest that a differential receptor-ligand interaction is involved and that the relative interactions of MC3R and MC4R with G protein are possibly quantitatively and qualitatively different.


Asunto(s)
Hormona Adrenocorticotrópica/metabolismo , AMP Cíclico/metabolismo , Regulación de la Expresión Génica , Receptores de Corticotropina/metabolismo , Transcripción Genética , Hormona Adrenocorticotrópica/análogos & derivados , Hormona Adrenocorticotrópica/química , Aminoácidos/química , Animales , Sitios de Unión , Northern Blotting , Células CHO , Línea Celular , Cricetinae , Genes Reporteros , Humanos , Ligandos , Luciferasas/metabolismo , Espectroscopía de Resonancia Magnética , Modelos Químicos , Modelos Moleculares , Mutación , Unión Proteica , Receptor de Melanocortina Tipo 3 , Receptor de Melanocortina Tipo 4 , Receptores de Corticotropina/química , Elementos de Respuesta , Factores de Tiempo , alfa-MSH/química , alfa-MSH/metabolismo
15.
J Esthet Restor Dent ; 13(6): 370-8, 2001.
Artículo en Inglés | MEDLINE | ID: mdl-11778856

RESUMEN

PURPOSE: This study investigated the effect of the presence, absence, and aging of a heat-enhancing compound (colorant) added to bleaching gel on the temperature rise of the gel itself, as well as the temperature rise within the pulp chamber, when a tooth was exposed to a variety of light-curing units in vitro. MATERIALS AND METHODS: An extracted human upper central incisor was fitted with thermocouples placed in the pulp chamber as well as on the facial tooth surface. A temperature-controlled simulated intrapulpal fluid flow was provided to the tooth, and bleaching agent (Opalesence XTRA, Ultradent) containing heat-enhancing colorant, aged colorant, or no colorant was applied to the facial surface. The tooth and light-curing unit were placed in a thermostatically controlled oven at 37 degrees C, and real-time gel and intrapulpal temperature values were recorded digitally. Light-curing units used were a plasma arc light (PAC) (PowerPac, ADT), a conventional quartz tungsten halogen source (QTH) (Optilux 501, Demetron/Kerr), the QTH light used in high-power (bleaching) mode, and an argon ion laser (AccuCure 3000, LaserMed). An exposure scenario simulating light-enhanced bleaching of 10 upper teeth was developed. Temperature rise over the pre-exposure, baseline value associated with the last light exposure in the bleaching sequence was calculated for each curing and bleaching combination. Five replications for each test condition were made. Temperature rise values were compared using analysis of variance (ANOVA) at a preset alpha of 0.05. RESULTS: When fresh colorant-containing bleach was used, the PAC light increased bleach temperature 39.3 degrees C above baseline. With no added colorant, temperature rise was 37.1 degrees C. The QTH light in bleach mode resulted in gel temperature 24.8 degrees C above baseline, whereas the temperature increase was only 11.5 degrees C when no colorant was used. Conventional QTH light use increased fresh bleach temperature by 17.7 degrees C, whereas an increase of only 11.1 degrees C was measured without colorant. The argon ion laser produced equivalent temperature rise regardless of the presence or freshness of the colorant, approximately 9.4 degrees C. Intrapulpal temperatures were all significantly lower than those recorded in the bleaching gel and ranged from 5 degrees to 8 degrees C. As a rule, the presence of fresh heat-enhancing colorant in the bleaching gel resulted in a significant intrapulpal temperature increase (approximately 1 degrees C) over that reached using other lights. The PAC and the QTH light used in bleach mode induced greater intrapulpal temperature rise than the laser. CLINICAL SIGNIFICANCE: Freshness of bleaching agent incorporating light-activated, heat-enhancing colorant influences temperature rise of bleaching gel and also may increase intrapulpal temperature values. Use of intense lights does elevate bleach temperature and also results in increased intrapulpal temperature that may further impact on patient sensitivity and pulpal health resulting from this treatment.


Asunto(s)
Peróxidos/química , Peróxidos/efectos de la radiación , Blanqueamiento de Dientes/métodos , Urea/análogos & derivados , Urea/química , Urea/efectos de la radiación , Análisis de Varianza , Temperatura Corporal , Peróxido de Carbamida , Color , Pulpa Dental/fisiología , Combinación de Medicamentos , Calor , Humanos , Incisivo , Rayos Infrarrojos , Rayos Láser , Luz , Estadísticas no Paramétricas , Rayos Ultravioleta
16.
Biochem J ; 352 Pt 3: 907-11, 2000 Dec 15.
Artículo en Inglés | MEDLINE | ID: mdl-11104702

RESUMEN

We have reported previously on the expression of recombinant human type X collagen (hrColX) in HEK 293 and HT 1080 cells by using the eukaryotic expression vector pCMVsis (in which CMV stands for cytomegalovirus). Several stably transfected clones secreted full-length triple-helical hrColX molecules in large amounts, but the secreted collagen was underhydroxylated, with a hydroxyproline-to-proline ratio of 0.25 and a melting temperature (T(m)) of 31 degrees C. By comparison, native chicken type X procollagen has a T(m) of 46 degrees C. To stabilize the triple helix of hrColX, an hrColX-expressing clone (A6/16) was co-transfected with both alpha and beta subunits of human prolyl 4-hydroxylase. Clones were selected that secreted proalpha1(X) collagen chains with an apparent molecular mass of 75 kDa and an increased hydroxyproline-to-proline ratio of close to 0.5. As a result of enhanced prolyl hydroxylation, the T(m) of the hrColX was increased to 41 degrees C as measured by CD analysis at various temperatures. The CD spectra indicated a minimum ellipticity at 198 nm and a peak at 225 nm at 20 degrees C, confirming the presence of a triple helix. The same T(m) of 41 degrees C was measured for the triple-helical core fragments of hrColX of 60-65 kDa that were retained after brief digestion with chymotrypsin/trypsin at increasing temperatures. This shows that the human cell line HEK-293 is suitable for the simultaneous expression of three genes and the stable production of substantial amounts of recombinant, fully hydroxylated type X collagen over several years.


Asunto(s)
Colágeno/química , Colágeno/metabolismo , Hidroxiprolina/metabolismo , Procolágeno-Prolina Dioxigenasa/química , Procolágeno-Prolina Dioxigenasa/metabolismo , Animales , Línea Celular , Pollos , Quimotripsina/metabolismo , Dicroismo Circular , Colágeno/genética , Colágeno/aislamiento & purificación , Expresión Génica , Humanos , Hidroxilación , Peso Molecular , Fragmentos de Péptidos/química , Fragmentos de Péptidos/metabolismo , Procolágeno-Prolina Dioxigenasa/genética , Estructura Secundaria de Proteína , Subunidades de Proteína , ARN Mensajero/análisis , ARN Mensajero/genética , Proteínas Recombinantes/química , Proteínas Recombinantes/aislamiento & purificación , Proteínas Recombinantes/metabolismo , Temperatura , Termodinámica , Transfección , Tripsina/metabolismo
17.
Nature ; 408(6809): 199-203, 2000 Nov 09.
Artículo en Inglés | MEDLINE | ID: mdl-11089973

RESUMEN

Signalling through dopamine D2 receptors governs physiological functions related to locomotion, hormone production and drug abuse. D2 receptors are also known targets of antipsychotic drugs that are used to treat neuropsychiatric disorders such as schizophrenia. By a mechanism of alternative splicing, the D2 receptor gene encodes two molecularly distinct isoforms, D2S and D2L, previously thought to have the same function. Here we show that these receptors have distinct functions in vivo; D2L acts mainly at postsynaptic sites and D2S serves presynaptic autoreceptor functions. The cataleptic effects of the widely used antipsychotic haloperidol are absent in D2L-deficient mice. This suggests that D2L is targeted by haloperidol, with implications for treatment of neuropsychiatric disorders. The absence of D2L reveals that D2S inhibits D1 receptor-mediated functions, uncovering a circuit of signalling interference between dopamine receptors.


Asunto(s)
Isoformas de Proteínas/fisiología , Receptores de Dopamina D2/fisiología , Animales , Apomorfina/farmacología , Benzazepinas/farmacología , Catalepsia/metabolismo , Quimera , Dopamina/metabolismo , Agonistas de Dopamina/farmacología , Antagonistas de Dopamina/farmacología , Haloperidol/farmacología , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Mutagénesis , Isoformas de Proteínas/química , Quinpirol/farmacología , Receptores de Dopamina D2/química , Receptores de Dopamina D2/genética , Transducción de Señal , Espiperona/farmacología , Sinapsis/fisiología
18.
Gene ; 257(1): 45-55, 2000 Oct 17.
Artículo en Inglés | MEDLINE | ID: mdl-11054567

RESUMEN

Protein tyrosine phosphorylation is regulated by protein tyrosine kinase and protein tyrosine phosphatase activities. These two counteracting proteins are implicated in cell growth and transformation. Using polymerase chain reaction with degenerate primers, we have identified a novel mouse protein tyrosine phosphatase (PTP). This cDNA contains a single open reading frame of the predicted 926 amino acids. Those predicted amino acids showed significant identity with human megakaryocyte protein-tyrosine phosphatase by 91% in nucleotide sequences and 94% in amino acid sequences. We have identified that expression of this PTP is highly enriched in the testis in mouse and human and has been termed here as a 'testis-enriched phosphatase' (TEP). Northern analysis detected two mRNA species of 3.7 and 3.2kb for this PTP in mouse testis and the expression of TEP is regulated during development. The recombinant phosphatase domain possesses protein tyrosine phosphatase activity when expressed in Escherichia coli. Immunohistochemical analysis of the cellular localization of TEP on mouse testis sections showed that this PTP is specifically expressed in spermatocytes and spermatids within seminiferous tubules, suggesting an important role in spermatogenesis.


Asunto(s)
Megacariocitos/enzimología , Proteínas Tirosina Fosfatasas/genética , Testículo/enzimología , Secuencia de Aminoácidos , Animales , Secuencia de Bases , Northern Blotting , Clonación Molecular , ADN Complementario/química , ADN Complementario/genética , Femenino , Regulación del Desarrollo de la Expresión Génica , Regulación Enzimológica de la Expresión Génica , Humanos , Inmunohistoquímica , Masculino , Megacariocitos/citología , Ratones , Datos de Secuencia Molecular , Proteínas Tirosina Fosfatasas/metabolismo , ARN Mensajero/genética , ARN Mensajero/metabolismo , Alineación de Secuencia , Análisis de Secuencia de ADN , Homología de Secuencia de Aminoácido , Testículo/crecimiento & desarrollo , Distribución Tisular
19.
Lancet ; 355(9222): 2222, 2000 Jun 24.
Artículo en Inglés | MEDLINE | ID: mdl-10881902

RESUMEN

We report two patients who developed Pisa syndrome after treatment with cholinesterase inhibitors--cognition-enhancing novel agents for patients with Alzheimer's disease. Cholinergic excess could be another factor in Pisa syndrome, especially in cholinergically-imbalanced Alzheimer's disease.


Asunto(s)
Inhibidores de la Colinesterasa/efectos adversos , Distonía/inducido químicamente , Fenilcarbamatos , Postura , Anciano , Enfermedad de Alzheimer/tratamiento farmacológico , Carbamatos/efectos adversos , Donepezilo , Antagonistas de Dopamina/efectos adversos , Femenino , Humanos , Indanos/efectos adversos , Trastornos de la Memoria/tratamiento farmacológico , Persona de Mediana Edad , Fármacos Neuroprotectores/efectos adversos , Nootrópicos/efectos adversos , Piperidinas/efectos adversos , Agitación Psicomotora/tratamiento farmacológico , Risperidona/efectos adversos , Rivastigmina , Síndrome
20.
Stroke ; 31(5): 1111-5, 2000 May.
Artículo en Inglés | MEDLINE | ID: mdl-10797173

RESUMEN

BACKGROUND AND PURPOSE: This study was designed to evaluate cerebral hemodynamic changes related to diabetes mellitus (DM) with transcranial Doppler ultrasonography (TCD). METHODS: We measured the flow velocities and the Gosling pulsatility index (PI) of the middle cerebral artery (MCA), extracranial internal carotid artery (ICA), and basilar artery (BA) in 56 stroke-free, normotensive patients with type 2 DM and 70 age- and gender-matched healthy volunteers. Patients were divided into 2 groups according to the presence of microvascular complications such as retinopathy, nephropathy, and neuropathy. RESULTS: Patients showed slightly lower hematocrit and higher serum fibrinogen levels than control subjects, but other clinical profiles, including stroke risk factors except for diabetes, were comparable between patients and controls. The flow velocity of the ICA but not the MCA and BA in patients regardless of the complication was significantly higher than that in controls. The PIs of the MCA and ICA were significantly higher in patients with complication than those without complication, as well as in controls. The PI of the BA was also significantly higher, even in patients without complication, than in controls. The PIs of the MCA and ICA but not the BA were closely correlated with the duration of DM (r(2)=0.46 and 0.34, respectively). CONCLUSIONS: This study defines TCD findings of diabetes-related cerebral hemodynamic changes and suggests that the PI reflects microangiopathic changes of cerebral vessels.


Asunto(s)
Arterias/fisiopatología , Circulación Cerebrovascular , Trastornos Cerebrovasculares/fisiopatología , Angiopatías Diabéticas/fisiopatología , Anciano , Trastornos Cerebrovasculares/diagnóstico por imagen , Angiopatías Diabéticas/diagnóstico por imagen , Femenino , Humanos , Masculino , Persona de Mediana Edad , Ultrasonografía Doppler Transcraneal , Vasodilatación
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