Asunto(s)
Alérgenos/inmunología , Anafilaxia/inmunología , Antígenos de Plantas/inmunología , Eriobotrya/efectos adversos , Hipersensibilidad/inmunología , Anafilaxia/diagnóstico , Frutas/efectos adversos , Humanos , Hipersensibilidad/diagnóstico , Inmunoglobulina E/inmunología , Fenotipo , Extractos Vegetales/efectos adversos , Extractos Vegetales/inmunologíaRESUMEN
No disponible
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Humanos , Alérgenos/inmunología , Anafilaxia/inmunología , Antígenos de Plantas/inmunología , Eriobotrya/efectos adversos , Hipersensibilidad/inmunología , Anafilaxia/diagnóstico , Frutas/efectos adversos , Fenotipo , Extractos Vegetales/efectos adversos , Extractos Vegetales/inmunología , Hipersensibilidad/diagnóstico , Inmunoglobulina E/inmunologíaRESUMEN
BACKGROUND AND PURPOSE: Elevation of glutamate, an excitatory amino acid, during inflammation and injury plays a crucial role in the reception and transmission of sensory information via ionotropic and metabotropic receptors. This study aimed to investigate the mechanisms underlying the biphasic effects of metabotropic glutamate mGlu5 receptor activation on responses to noxious heat. EXPERIMENTAL APPROACH: We assessed the effects of intraplantar quisqualate, a non-selective glutamate receptor agonist, on heat and mechanical pain behaviours in mice. In addition, the effects of quisqualate on the intracellular calcium response and on membrane currents mediated by TRPV1 channels, were examined in cultured dorsal root ganglion neurons from mice. KEY RESULTS: Activation of mGlu5 receptors in hind paw transiently increased, then decreased, the response to noxious heat. In sensory neurons, activation of mGlu5 receptors potentiated TRPV1-mediated intracellular calcium elevation, while terminating activation of mGlu5 receptors depressed it. TRPV1-induced currents were potentiated by activation of mGlu5 receptors under voltage clamp conditions and these disappeared after washout. However, voltage-gated calcium currents were inhibited by the mGlu5 receptor agonist, even after washout. CONCLUSIONS AND IMPLICATIONS: These results suggest that, in sensory neurons, mGlu5 receptors biphasically modulate TRPV1-mediated intracellular calcium response via transient potentiation of TRPV1 channel-induced currents and persistent inhibition of voltage-gated calcium currents, contributing to heat hyper- and hypoalgesia.
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Calcio/metabolismo , Ácido Quiscuálico/farmacología , Receptor del Glutamato Metabotropico 5/metabolismo , Células Receptoras Sensoriales/efectos de los fármacos , Trastornos Somatosensoriales/metabolismo , Canales Catiónicos TRPV/metabolismo , Animales , Canales de Calcio/fisiología , Capsaicina/farmacología , Células Cultivadas , Ganglios Espinales/citología , Calor , Masculino , Ratones , Ratones Endogámicos C57BL , Receptor del Glutamato Metabotropico 5/agonistas , Células Receptoras Sensoriales/metabolismo , Células Receptoras Sensoriales/fisiología , Canales Catiónicos TRPV/fisiologíaRESUMEN
BACKGROUND: Gliadins have been implicated in immunoglobulin E (IgE)-mediated allergy to ingested wheat and omega-5-gliadin is known to represent a major allergen in wheat-dependent exercise-induced anaphylaxis. Less known is whether omega-5-gliadin is a clinically relevant allergen in children with immediate allergy to ingested wheat. This study investigates whether specific IgE antibodies to omega-5-gliadin (sIgE-omega-5-gliadin-ab) could be used as a marker for oral wheat challenge outcome in wheat-sensitized children. A secondary objective was to study whether the level of sIgE-omega-5-gliadin was related to symptom severity in children with a positive challenge test. METHODS: Serum samples from 88 children sensitized to wheat, of whom 35 underwent wheat challenge, were collected consecutively. sIgE-omega-5-gliadin-ab was related to a physician's diagnosis of wheat allergy and challenge symptoms. RESULTS: The mean concentration of sIgE-omega-5-gliadin-ab was 7.25 kU(A)/l in patients with wheat allergy and 1.08 kU(A)/l in patients with no wheat allergy (P < 0.01). sIgE-omega-5-gliadin-ab was only detected in 12 of the non-wheat allergic children and 11 of them had a specific IgE to wheat below 1.30 kU(A)/l. Children reacting with severe symptoms upon challenge (n = 8) had increased levels of sIgE-omega-5-gliadin-ab compared to children with moderate, mild or no symptoms (P < 0.001). CONCLUSIONS: The presence of sIgE-omega-5-gliadin-ab is related to the reaction level to wheat challenge outcome in wheat-sensitized children. The sIgE-omega-5-gliadin-ab was found to be associated with a strong convincing history of wheat allergy also in those cases when oral food challenge was avoided. The sIgE-omega-5-gliadin-ab level may serve as a marker for clinical reactivity in wheat-sensitized individuals.
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Alérgenos/inmunología , Gliadina/inmunología , Inmunoglobulina E/sangre , Boca/inmunología , Triticum/inmunología , Hipersensibilidad al Trigo/inmunología , Antígenos de Plantas , Niño , Preescolar , Femenino , Humanos , Lactante , Japón , Masculino , Hipersensibilidad al Trigo/sangreRESUMEN
The inter- and intramolecular interactions of the carbonyl moieties at the polar interface of a phospholipid membrane are probed by using nonlinear femtosecond infrared spectroscopy. Two-dimensional IR correlation spectra separate homogeneous and inhomogeneous broadenings and show a distinct cross-peak pattern controlled by electrostatic interactions. The inter- and intramolecular electrostatic interactions determine the inhomogeneous character of the optical response. Using molecular dynamics simulation and the nonlinear exciton equations approach, we extract from the spectra short-range structural correlations between carbonyls at the interface.
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Fosfolípidos/química , Espectrofotometría Infrarroja/métodos , Electricidad Estática , Anisotropía , Carbono/química , Simulación por Computador , Cinética , Membrana Dobles de Lípidos/química , Modelos Estadísticos , Conformación Molecular , Espectrofotometría/métodos , Espectroscopía Infrarroja por Transformada de FourierRESUMEN
A minicapillary viscometer utilizing <0.5 ml of sample at a volume fraction of <0.1% is described. The calculated a/b of DPPC/DPPG multilamellar liposome was 1.14 as prolate ellipsoids and a/b of dioleoylpropyltrimethyl ammonium methylsulfate-DNA complex at a charge ratio of 4:1 (+/-) was 3.7 as prolate ellipsoids or 4.9 as oblate ellipsoids. The deviation of shape from perfect sphere is thus expressed quantitatively in more than two significant figures. In these measurement, the necessary amount of DNA is <0.5 mg.
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ADN/química , Análisis de Falla de Equipo/instrumentación , Lípidos/química , Liposomas/química , Ensayo de Materiales/instrumentación , Fluidez de la Membrana , Microquímica/instrumentación , Microfluídica/instrumentación , Acción Capilar , ADN/ultraestructura , Sistemas de Liberación de Medicamentos/métodos , Diseño de Equipo , Análisis de Falla de Equipo/métodos , Sustancias Macromoleculares , Ensayo de Materiales/métodos , Microquímica/métodos , Microfluídica/métodos , Conformación Molecular , Tamaño de la Partícula , Reproducibilidad de los Resultados , Tamaño de la Muestra , Sensibilidad y Especificidad , ViscosidadRESUMEN
Molecular dynamics (MD) simulations of fully hydrated bilayers in the liquid-crystalline state made of 1-palmitoyl-2-oleoyl-phosphatidylcholine (POPC) or 1-palmitoyl-2-elaidoyl-phosphatidylcholine (PEPC) were carried out to investigate the effect of the incorporation of a double bond in the phosphatidylcholine (PC) beta-chain (cis or trans) on the membrane/water interface. The bilayers reached thermal equilibrium after 3 and 1 ns of MD simulations, respectively, and productive runs were carried out for 3 ns for each bilayer. As reference systems, the 1,2-dimyristoyl-phosphatidylcholine (DMPC) bilayer (M. Pasenkiewicz-Gierula, Y. Takaoka, H. Miyagawa, K. Kitamura, and A. Kusumi, 1999, Biophys. J. 76:1228-1240) and DMPC-cholesterol (Chol) bilayer containing 22 mol % Chol (M. Pasenkiewicz-Gierula, T. Róg, K. Kitamura, A. and Kusumi, 2000, Biophys. J. 78:1376-1389) were used. The study shows that at the interface of POPC, PEPC, and DMPC-Chol bilayers, average numbers of PC-water and PC-PC interactions are similar and, respectively, greater and smaller than in the DMPC bilayer. The average area/PC in mono-unsaturated bilayers is approximately 4 A(2) larger than in the DMPC bilayer; nevertheless, a strong correlation was found between a single molecular area (SMA) of a PC and the number of interactions this PC makes; i.e., PCs (either saturated or unsaturated) with the same SMA form similar numbers of intermolecular links. The numbers and corresponding SMAs are distributed about averages pertinent to each bilayer. No significant difference between cis and trans bonds was found.
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Membrana Dobles de Lípidos/química , Membrana Dobles de Lípidos/metabolismo , Modelos Moleculares , Fosfolípidos/química , Fosfolípidos/metabolismo , Agua/metabolismo , Sitios de Unión , Dimiristoilfosfatidilcolina/química , Dimiristoilfosfatidilcolina/metabolismo , Enlace de Hidrógeno , Ácido Oléico/química , Ácido Oléico/metabolismo , Ácidos Oléicos , Fosfatidilcolinas/química , Fosfatidilcolinas/metabolismo , Electricidad EstáticaRESUMEN
Membrane fusion is a key event in vesicular trafficking in every cell, and many fusion-related proteins have been identified. However, how the actual fusion event occurs has not been elucidated. By using molecular dynamics simulations we found that when even a small region of two membranes is closely apposed such that only a limited number of water molecules remain in the apposed area (e.g., by a fusogenic protein and thermal membrane fluctuations), dramatic lipid disorientation results within 100 ps-2 ns, which might initiate membrane fusion. Up to 12% of phospholipid molecules in the apposing layers had their alkyl chains outside the hydrophobic region, lying almost parallel to the membrane surface or protruding out of the bilayer by 2 ns after two membranes were closely apposed.
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Membrana Celular/química , Membrana Celular/metabolismo , Fusión de Membrana , Lípidos de la Membrana/metabolismo , Modelos Moleculares , Simulación por Computador , Hidrocarburos/química , Hidrocarburos/metabolismo , Enlace de Hidrógeno , Conformación Molecular , Electricidad Estática , Agua/metabolismoRESUMEN
This report addresses the following problems associated with the generation of computer models of phospholipid bilayer membranes using molecular dynamics simulations: arbitrary initial structures and short equilibration periods, an Ewald-induced strong coupling of phospholipids, uncertainty regarding which value should be used for surface tension to alleviate the problem of the small size of the membrane, and simultaneous realization of both order parameters and the surface area. We generated a computer model of the liquid-crystalline L-alpha-dimyristoylphosphatidylcholine (DMPC) bilayer, starting from a configuration based on a crystal structure (rather than from an arbitrary structure). To break the crystalline structure, a 20-ps high-temperature pulse of 510 K (but not 450 or 480 K) was effective. The system finally obtained is an all-atom model, with Ewald summation to evaluate Coulombic interactions and a constant surface tension of 35 dynes/cm/water-membrane interface, equilibrated for 12 ns (over 50 ns total calculation time), which reproduces all of the experimentally observed parameters examined in this work. Furthermore, this model shows the presence of significant orientational correlations between neighboring alkyl chains and between shoulder vectors (which show the orientations of the lipids about their long axes) of neighboring DMPCs.
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Dimiristoilfosfatidilcolina/química , Membrana Dobles de Lípidos/química , Simulación por Computador , Calor , Cinética , Modelos Moleculares , Conformación Molecular , Termodinámica , AguaRESUMEN
Antibody catalysts for the removal of the p-nitrobenzyl ester protecting group have been generated to accommodate a broad range of substrates. Antibody 7B9, which was elicited against p-nitrobenzyl phosphonate 1, catalyzed the hydrolyses of p-nitrobenzyl monoesters of nonsubstituted, and beta- and gamma-substituted glutaric acids with almost identical Km and kcat values. In addition, 7B9 displayed substrate tolerance towards the a-substituents and accepted the p-nitrobenzyl esters of Leu, Norleu, and Phe. To define the molecular basis of the broad substrate tolerance, we have cloned and sequenced the antibody and constructed a model of the active-site-hapten complex. The model showed a relatively shallow pocket of the antigen-combining site that accommodates the p-nitrobenzyl moiety, and this is consistent with the observed substrate specificity. Thus, in the antibody-catalyzed reaction, the alpha-, beta-, and gamma-substituents of the substrates should be outside the combining site and ignored by the antibody recognition. A structural comparison of 7B9 with antibody D2.3, elicited against the structurally similar haptenic phosphonate, suggests the significance of the linker moiety in hapten design, which endows antibody catalysts with broad substrate specificity. These investigations provide new strategies for the generation of catalytic antibodies that accept a broad range of substrates for practical applications in organic synthetic chemistry.
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Anticuerpos Catalíticos/metabolismo , Organofosfonatos/metabolismo , Secuencia de Aminoácidos , Animales , Anticuerpos Catalíticos/genética , Sitios de Unión , Clonación Molecular , Ésteres/metabolismo , Glutaratos/metabolismo , Cinética , Ratones , Modelos Moleculares , Datos de Secuencia Molecular , Alineación de Secuencia , Especificidad por SustratoRESUMEN
To promote our better understanding of the dynamic stability of the bovine cathepsin B structure, which is characterized by an extra disulfide bond at Cys148-Cys252 from the other species, and of the binding stability of CA074 (a cathepsin B-specific inhibitor), molecular dynamics (MD) simulations were performed for the enzyme and its CA074 complex, assuming a system in aqueous solution at 300 K. The MD simulation covering 400 ps indicated that the existence of a Cys148-Cys252 disulfide bond increases the conformational flexibility of the occluding loop, although the conformational stability of the overall structure is little affected. The structural characteristics of the complex elucidated by X-ray analysis were suggested to be also intrinsic and stable in the dynamic state; the hydrogen bonding/electrostatic interactions between the main and side chains of CA074 and the Sn and Sn' subsites of the enzyme were maintained throughout the MD simulation. Furthermore, the simulation made clear that the binding of CA074 significantly restricted the conformational flexibility of the substrate binding region, especially the occluding loop, of cathepsin B. Statistical analyses during the simulation suggest that the selectivity of CA074 for cathepsin B stems from the tight P1'-S1' and P2'-S2' interactions, assisted in particular by double hydrogen bonds between the carboxyl two oxygens of the CA074 C-terminus and the imidazole NH groups of His110 and His111 residues.
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Catepsina B/metabolismo , Inhibidores de Cisteína Proteinasa/metabolismo , Dipéptidos/metabolismo , Modelos Químicos , Animales , Catepsina B/antagonistas & inhibidores , Bovinos , Cistina/metabolismo , Disulfuros/metabolismo , Procesamiento de Imagen Asistido por Computador , Modelos Moleculares , Conformación Proteica , Estructura Terciaria de Proteína , Relación Estructura-ActividadAsunto(s)
Huesos/metabolismo , Calcio/metabolismo , Páncreas/fisiología , Animales , Humanos , Páncreas/metabolismoRESUMEN
AIM: To observe the role of interleukin (IL)-6 in the development of experimental autoimmune encephalomyelitis (EAE). METHODS: DA rats were immunized by injecting bovine myelin basic protein (MBP). mRNA of cytokines, such as IL-6, IL-10, TNF-alpha, TGF-beta 1, IFN-gamma, and iNOS, were detected by RT-PCR. MBP was injected into ear to induce delayed type cutaneous hypersensitivity response (DTH). Histological studies were performed on the spinal cord with HE staining. Nitric oxide (NO) production from cultured murine macrophage clones was stimulated with LPS plus IFN-gamma. RESULTS: DA rats developed EAE disease with a peak of severity on d 13 and d 14. Am-80 (1.0, 3.0 mg/kg), a selective IL-6 inhibitor, inhibited the symptoms in terms of deterioration as observed by the clinical score, body weight and histological findings, in a dose-related manner. A high dose of Am-80 (3.0 mg/kg for 12 d) did not completely inhibit the disease, but delayed the symptoms and enhanced the delayed response. By prolonging the duration of treatment (18 d), Am-80 inhibited the onset of EAE during administration, but the symptoms of EAE appeared after the administration was stopped. Am-80 administerd for 12 d inhibited the DTH response on d 11 but not on d 22. RT-PCR studies demonstrated a strong expression of IFN-gamma, IL-6, IL-10, TGF-beta 1, TNF-alpha, and iNOS mRNA in spinal cord 13 d after immunization. However IFN-gamma, IL-10, TNF-alpha, and iNOS mRNA expression (on d 13) was suppressed by Am-80, except in the case of IL-6, hence the effect of Am-80 on the expression of IL-6 mRNA was examined in additional experiments. After Am-80 was administered for 12 d or 18 d, the expression of IL-6 mRNA was inhibited on d 12 or d 18, but increased on d 13 or d 19, respectively. CONCLUSION: These findings suggest that inhibition of EAE by Am-80 is initiated by inhibition of IL-6 production.
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Benzoatos/farmacología , Citocinas/biosíntesis , Encefalomielitis Autoinmune Experimental/metabolismo , Interleucina-6/biosíntesis , Médula Espinal/metabolismo , Tetrahidronaftalenos/farmacología , Animales , Citocinas/genética , Encefalomielitis Autoinmune Experimental/inducido químicamente , Femenino , Interferón gamma/biosíntesis , Interferón gamma/genética , Interleucina-10/biosíntesis , Interleucina-10/genética , Interleucina-6/antagonistas & inhibidores , Interleucina-6/genética , Proteína Básica de Mielina , Óxido Nítrico Sintasa/biosíntesis , Óxido Nítrico Sintasa/genética , Óxido Nítrico Sintasa de Tipo II , ARN Mensajero/biosíntesis , ARN Mensajero/genética , RatasRESUMEN
This study was conducted to investigate the mechanism of interleukin-1beta (IL-1beta)-induced IL-6 production in human osteoblasts (MG-63 cells). Stimulation with IL-1beta resulted in the production of IL-6 and prostaglandin E(2) (PGE(2)). IL-6 production gradually increased and peaked 96 h after stimulation. IL-6 mRNA was detected between 4 and 72 h after IL-1beta stimulation. The patterns of PGE(2) production and the expression of cyclooxygenase-2 (COX-2) mRNA were biphasic after stimulation. Actinomycin D, cycloheximide, indomethacin, and NS-398 (COX-2 inhibitor) suppressed the production of IL-6 and PGE(2). Anti-PGE(2) antibody markedly reduced the production of IL-6. In addition, stimulation with 17-phenyl-PGE(2), a PGE receptor-1 (EP-1 receptor) agonist, led to the expression of IL-6 mRNA after pretreatment with IL-1beta. These findings indicate that IL-1beta-induced IL-6 production in MG-63 cells involves the following sequence of steps: IL-1beta-induced COX-2 activation, PGE(2) production, and EP-1 receptor signaling prior to IL-6 production.
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Dinoprostona/biosíntesis , Interleucina-1/fisiología , Interleucina-6/biosíntesis , Osteoblastos/metabolismo , Anticuerpos/inmunología , Secuencia de Bases , Línea Celular , Ciclooxigenasa 1 , Ciclooxigenasa 2 , Inhibidores de la Ciclooxigenasa 2 , Inhibidores de la Ciclooxigenasa/farmacología , Cartilla de ADN , Dinoprostona/agonistas , Dinoprostona/inmunología , Humanos , Interleucina-6/genética , Isoenzimas/genética , Cinética , Proteínas de la Membrana , Osteoblastos/efectos de los fármacos , Prostaglandina-Endoperóxido Sintasas/genética , Inhibidores de la Síntesis de la Proteína/farmacología , ARN Mensajero/genética , ARN Mensajero/metabolismoRESUMEN
This study was conducted to investigate a mechanism of the anti-inflammatory action of mesoporphyrin, especially the effect on the production of cytokines by some cultured inflammatory cells. Mesoporphyrin had no effect on lipopolysaccharide-induced tumor necrosis factor-alpha production by RAW 264.7 cells (murine macrophage-like cells). Mesoporphyrin inhibited interferon-gamma production by 1E10.H2 cells (murine T helper-1 cells), but not interleukin-4 production by D10.G4.1 cells (murine T helper-2 cells). Mesoporphyrin inhibited interleukin-6 production by human osteoblast-like MG-63 cells. This inhibition of interleukin-6 production is closely related to the suppression of prostaglandin E2 generation by interfering cyclooxygenase 1 and 2 enzyme activities. These data suggest that the inhibition of cytokine production is one of the anti-inflammatory mechanisms of mesoporphyrin.
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Antiinflamatorios/farmacología , Citocinas/metabolismo , Linfocitos/efectos de los fármacos , Macrófagos/efectos de los fármacos , Mesoporfirinas/farmacología , Osteoblastos/efectos de los fármacos , Animales , Células Cultivadas , Dinoprostona/metabolismo , Humanos , Inflamación/tratamiento farmacológico , Inflamación/patología , Interferón gamma/metabolismo , Interleucina-4/metabolismo , Interleucina-6/metabolismo , Linfocitos/inmunología , Macrófagos/inmunología , Ratones , Osteoblastos/inmunología , Células Tumorales Cultivadas , Factor de Necrosis Tumoral alfa/metabolismoRESUMEN
The present study was designed to compare the clinical efficacy of low-dose step-up follicle stimulating hormone (FSH) administration with conventional FSH protocol (FSH was injected daily starting with a dose of 150 IU), both combined with intrauterine insemination (IUI), for the treatment of unexplained infertility. A total of 97 unexplained infertility couples was randomly assigned to one or other of the two treatment groups, either conventional FSH with IUI (48 patients) or low-dose step-up FSH with IUI (49 patients), and only the first treatment cycle was evaluated in each protocol. The difference in pregnancy rates per cycle was not statistically significant between the low-dose FSH group and the conventional group [seven of 49 (14.3%) and seven of 48 (14.6%) respectively]. A significant reduction in the incidence of ovarian hyperstimulation syndrome (OHSS) was observed in the low-dose group (8.3% versus 27.1%, P < 0.05). The incidence of moderate OHSS requiring hospitalization was reduced significantly in the low-dose group (low-dose 0% versus conventional 16.7%, P < 0.01). However, the low-dose protocol did not completely prevent multiple pregnancies. Our results suggest that the low-dose step-up FSH treatment appeared to be useful for the treatment of unexplained infertility because of the high pregnancy rates and the significant decrease in the incidence of OHSS.
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Hormona Folículo Estimulante/administración & dosificación , Infertilidad/tratamiento farmacológico , Adulto , Relación Dosis-Respuesta a Droga , Femenino , Hormona Folículo Estimulante/uso terapéutico , Hospitalización , Humanos , Incidencia , Infertilidad/etiología , Masculino , Síndrome de Hiperestimulación Ovárica/epidemiología , Síndrome de Hiperestimulación Ovárica/fisiopatología , Síndrome de Hiperestimulación Ovárica/prevención & control , Embarazo , Índice de Embarazo , Embarazo Múltiple , GemelosRESUMEN
Molecular dynamics simulation of the hydrated dimyristoylphosphatidylcholine (DMPC) bilayer membrane in the liquid-crystalline phase was carried out for 5 ns to study the interaction among DMPC headgroups in the membrane/water interface region. The phosphatidylcholine headgroup contains a positively charged choline group and negatively charged phosphate and carbonyl groups, although it is a neutral molecule as a whole. Our previous study (Pasenkiewicz-Gierula, M., Y. Takaoka, H. Miyagawa, K. Kitamura, and A. Kusumi. 1997. J. Phys. Chem. 101:3677-3691) showed the formation of water cross-bridges between negatively charged groups in which a water molecule is simultaneously hydrogen bonded to two DMPC molecules. Water bridges link 76% of DMPC molecules in the membrane. In the present study we show that relatively stable charge associations (charge pairs) are formed between the positively and negatively charged groups of two DMPC molecules. Charge pairs link 93% of DMPC molecules in the membrane. Water bridges and charge pairs together form an extended network of interactions among DMPC headgroups linking 98% of all membrane phospholipids. The average lifetimes of DMPC-DMPC associations via charge pairs, water bridges and both, are at least 730, 1400, and over 1500 ps, respectively. However, these associations are dynamic states and they break and re-form several times during their lifetime.
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Dimiristoilfosfatidilcolina/química , Membrana Dobles de Lípidos/química , Sitios de Unión , Fenómenos Biofísicos , Biofisica , Enlace de Hidrógeno , Modelos Moleculares , Electricidad Estática , Termodinámica , Agua/químicaRESUMEN
We investigated whether the incorporation of the sperm membrane into the oolemma contributes to the human plasma membrane block to polyspermy. We used zona pellucida-free oocytes fertilized by intracytoplasmic sperm injection (ICSI) or activated by parthenogenetic activation. Only two of the 35 pronuclear oocytes fertilized by spermatozoa (control) demonstrated one single penetrating spermatozoa. In contrast, the majority of ICSI and parthenogenetically activated pronuclear oocytes were penetrated with an average of three spermatozoa per oocyte. The number of fused and binding spermatozoa of ICSI and parthenogenetically activated oocytes were significantly higher than in control oocytes (3.5+/-0.6 and 4.3+/-0.6 for ICSI; 3.0+/-0.3 and 3.8+/-0.4 for activated and 0.2+/-0.1 and 0.6+/-0.2 for controls, respectively, P < 0.01). Furthermore, the cortical granules were released from the cortex of ICSI and calcium ionophore-puromycin-activated pronuclear oocytes to the same extent as that of pronuclear oocytes fertilized by spermatozoa. These results suggest that the establishment of the plasma membrane block to sperm penetration in the human oocyte may require a fusion process between sperm and oocyte plasma membranes.
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Fusión de Membrana/fisiología , Oocitos/fisiología , Interacciones Espermatozoide-Óvulo/fisiología , Espermatozoides/fisiología , Membrana Celular/fisiología , Femenino , Humanos , MasculinoRESUMEN
Am-80 is a newly snythesized retinoid with the structure of one aromatic amide among retinobenzoic acids. It exhibits specific biological activities of retinoic acid such as the activation of cellular differentiation and proliferation. We investigated the effect of Am-80 on collagen-induced arthritis (CIA) in mice and the immunopharmacological action on the production of several cytokines in the in vitro and in vivo models. Am-80, at doses of 0.3, 1 and 3 mg/kg, significantly inhibited the severity and development of the arthritis index, progression of foot pad swelling, bone damage and histopathological alterations. Am-80 also inhibited the production of anti-type II collagen (CII) IgG antibody, but did not affect the delayed-type hypersensitivity (DTH) response in arthritic mice. To determine the inhibitory mechanism of Am-80, we studied the effect of Am-80 on the production of cytokines. Am-80 did not affect the production of IFN-gamma by Th1 cells (1E10.H2 cells) and IL-4 by Th2 cells (D10.G4.1 cells), respectively. Am-80 selectively inhibited bacterial lipopolysaccharide (LPS)-induced IL-6, but not TNF-alpha and IL-1beta, production in mice. Moreover Am-80 inhibited IL-1beta induced IL-6 production and IL-6 mRNA expression in human osteoblast-like cells (MG-63). The inhibition of IL-6 production by Am-80 was due to downregulation of the pretranscription or the transcription of IL-6 in MG 63 cells. These findings suggest that the inhibitory effect of Am-80 on CIA is partially by modulating the production of the proinflammatory cytokine, IL-6.
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Artritis/tratamiento farmacológico , Benzoatos/farmacología , Citocinas/biosíntesis , Retinoides/farmacología , Tetrahidronaftalenos/farmacología , Animales , Antiinflamatorios/uso terapéutico , Artritis/metabolismo , Artritis/patología , Autoanticuerpos/sangre , Autoanticuerpos/inmunología , Células Cultivadas , Colágeno/inmunología , Femenino , Interleucina-1/biosíntesis , Interleucina-6/biosíntesis , Masculino , Ratones , Ratones Endogámicos DBA , Prednisolona/uso terapéutico , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Membrana Sinovial/patología , Factor de Necrosis Tumoral alfa/biosíntesisRESUMEN
BACKGROUND AND OBJECTIVES: Traumatic intracranial aneurysms (TICAs) are highly unstable lesions that may rupture within minutes after formation or remain quiescent for several weeks and manifest with delayed hemorrhage and neurologic deterioration. Mortality following a rupture may be 30% to 40%. Among all cerebral aneurysms, the incidence of TICAs is less than 1%; 20% to 30% of TICAs occur in children. METHODS AND MATERIALS: A child with a low-caliber craniocerebral gunshot wound deteriorated neurologically 12 days after the initial injury and emergency evacuation of an intracranial hematoma. A new massive left frontal hematoma was discovered, caused by the rupture of an unsuspected left pericallosal artery pseudoaneurysm. The new hematoma was evacuated, and the aneurysm was trapped using microsurgical techniques. RESULTS AND/OR CONCLUSIONS: A high index of suspicion should be maintained for delayed pseudoaneurysm genesis and rupture. A cerebral arteriogram should be obtained when significant subarachnoid hemorrhage or intraparenchymal hematomas are present, when missiles traverse major arteries, or when the pterional or cranioorbitofacial regions are violated. Treatment should be prompt.