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1.
Clin Exp Obstet Gynecol ; 41(1): 83-6, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-24707692

RESUMEN

OBJECTIVE: To examine whether conservative treatment with oral contraceptives is effective in the shrinkage of a peritoneal inclusion cyst (PIC). This is a case report of two patients with a PIC that developed after gynecological surgery. CASES: Both cases were suspected of a PIC based on the medical history, laboratory data, and image findings. It was difficult in differentiate a PIC from an ovarian tumor. Surgery was chosen at first. However, PICs in both cases recurred after surgery and were treated with oral contraceptives as a conservative treatment. PICs shrank after the treatment of oral contraceptives in both cases. CONCLUSION: Due to the high rate of recurrence following surgery, conservative treatment is recommended to treat PICs. Hormone therapy using oral contraceptives seems to have some therapeutic benefit for the PICs.


Asunto(s)
Anticonceptivos Orales Combinados/administración & dosificación , Anticonceptivos Hormonales Orales/administración & dosificación , Quistes/tratamiento farmacológico , Etinilestradiol/administración & dosificación , Levonorgestrel/administración & dosificación , Enfermedades Peritoneales/tratamiento farmacológico , Adulto , Quistes/diagnóstico , Quistes/etiología , Quistes/cirugía , Combinación de Medicamentos , Femenino , Procedimientos Quirúrgicos Ginecológicos/efectos adversos , Humanos , Persona de Mediana Edad , Enfermedades Peritoneales/diagnóstico , Enfermedades Peritoneales/etiología , Enfermedades Peritoneales/cirugía , Recurrencia , Escleroterapia , Adherencias Tisulares/cirugía
2.
Neuron ; 20(6): 1137-51, 1998 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-9655502

RESUMEN

In mammals, neurons are highly differentiated and play distinctive functions even in the same brain region. We found a novel cadherin-related neuronal receptor (Cnr) gene family by studying Fyn-binding activity in mouse brain. CNR1 protein is located in the synaptic junction and forms a complex with Fyn. Sequence analysis of eight Cnr products of approximately 20 genes indicates that these comprise a novel cadherin family of the cadherin superfamily. The expression patterns of each member of this novel family were grossly similar to each other but restricted to subpopulations of neurons of the same type. The diversity of the Cnr family genes suggests that there are molecular mechanisms that govern highly differentiated neural networks in the mammalian CNS.


Asunto(s)
Cadherinas/genética , Moléculas de Adhesión Celular Neuronal , Neuronas/química , Neuropéptidos/genética , Receptores de Superficie Celular , Sinapsis/química , Animales , Secuencia de Bases , Química Encefálica/genética , Cadherinas/análisis , Variación Genética , Ratones , Ratones Endogámicos C57BL , Datos de Secuencia Molecular , Familia de Multigenes/genética , Neocórtex/química , Neuropéptidos/análisis , Bulbo Olfatorio/química , Protocadherinas , Homología de Secuencia de Aminoácido
3.
AJNR Am J Neuroradiol ; 37(9): 1696-9, 2016 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-27102315

RESUMEN

We describe a case series of suspected metallic embolism after coil embolization for intracranial aneurysms. Between January 2012 and December 2014, 110 intracranial aneurysms had been treated by coil embolization in our institution. In 6 cases, the postprocedural MR imaging revealed abnormal spotty lesions not detected on the preprocedural MR imaging. The lesions were also undetectable on the postprocedural CT scan. They were demonstrated as low-intensity spots on T1WI, T2WI, DWI, and T2*-weighted imaging. On DWI, they were accompanied by bright "halo," and on T2*-weighted imaging, they showed a "blooming" effect. In 3 of the 6 cases, follow-up MR imaging was available and all the lesions remained and demonstrated no signal changes. Although histologic examination had not been performed, these neuroradiologic findings strongly supported the lesions being from metallic fragments. No specific responsible device was detected after reviewing all the devices used for the neuroendovascular treatment in the 6 cases.


Asunto(s)
Embolización Terapéutica/efectos adversos , Aneurisma Intracraneal/terapia , Embolia Intracraneal/etiología , Adulto , Anciano , Anciano de 80 o más Años , Imagen de Difusión por Resonancia Magnética , Femenino , Humanos , Embolia Intracraneal/diagnóstico por imagen , Imagen por Resonancia Magnética , Masculino , Metales , Persona de Mediana Edad , Estudios Retrospectivos , Tomografía Computarizada por Rayos X , Resultado del Tratamiento
4.
J Neurosci ; 19(14): 5711-20, 1999 Jul 15.
Artículo en Inglés | MEDLINE | ID: mdl-10407012

RESUMEN

The AMPA-preferring subtype of ionotropic glutamate receptors (GluRs) is a hetero-oligomeric ion channel assembled from various combinations of four subunits: GluR1, GluR2, GluR3, and GluR4. Antagonists of these receptors can mitigate the effects of experimental spinal cord injury (SCI), indicating that these receptors play a significant role in pathophysiology after spinal trauma. We tested the hypothesis that SCI alters expression of AMPA receptors using a standardized thoracic weight-drop model of rat contusive spinal cord injury. AMPA receptor subunit expression was measured at 24 hr and at 1 month after SCI with quantitative Western blot analysis and in situ hybridization. GluR2 protein levels were preferentially reduced near the injury site 24 hr after SCI. This reduction persisted at 1 month. At a cellular level, a significant decrease in both GluR2 and GluR4 mRNA was found in spared ventral motor neurons adjacent to the injury site and distal to it, with other AMPA subunit mRNAs maintained at control levels. In contrast, only GluR1 mRNA was decreased in the sympathetic preganglionic neurons of the intermediolateral horn. These results suggest population-specific and long-lasting changes in neuronal AMPA receptor composition, which may alter response to glutamate after SCI. These alterations may contribute not only to acute neuropathological consequences of injury, but they may also be partially responsible for the altered functional state of preserved tissue seen chronically after SCI.


Asunto(s)
Regulación de la Expresión Génica , Neuronas/metabolismo , Receptores AMPA/genética , Traumatismos de la Médula Espinal/metabolismo , Médula Espinal/metabolismo , Animales , Elementos sin Sentido (Genética) , Autorradiografía , Secuencia de Bases , Contusiones , Modelos Animales de Enfermedad , Femenino , Datos de Secuencia Molecular , Actividad Motora , Neuronas Motoras/metabolismo , Neuronas Motoras/fisiología , Neuronas/clasificación , Neuronas/fisiología , ARN Mensajero/análisis , ARN Mensajero/genética , Ratas , Ratas Sprague-Dawley , Receptores AMPA/biosíntesis , Reflejo , Médula Espinal/fisiopatología , Traumatismos de la Médula Espinal/fisiopatología , Factores de Tiempo , Transcripción Genética
5.
Biochim Biophys Acta ; 1290(1): 83-8, 1996 May 21.
Artículo en Inglés | MEDLINE | ID: mdl-8645711

RESUMEN

The force required to break the bond between skeletal muscle actin and alpha-actinin (unbinding force) was measured at the level of individual molecules with an optical trapping technique. An actin filament, to the barbed-end of which was attached a gelsolin-coated polystyrene bead, was bound to alpha-actinin molecules adsorbed to a nitrocellulose-coated glass surface (approximately equal to 1 alpha-actinin molecule per 1 micron actin filament). The filament-bound bead was held by the optical trap and the force was applied to break the bond by pulling the bead. The unbinding force ranged from 1.4 to 44 pN. The average magnitude of the force was approximately equal to 18 pN. As the probability of the bond breakage has been suggested to be governed by the magnitude of the external force, the relationship was studied between the magnitude of the unbinding force and the time required to break the bond (unbinding time). The unbinding time ranged from approximately equal to 0.1 to approximately equal to 20 seconds, and tended to become shorter as the unbinding force became larger. The unbinding time seemed to be classifiable into two major groups: one group having a time value of 1 sec or less and the other having a time value ranging from several to 20 seconds. This suggests the existence of at least two classes of the actin-actinin bonds.


Asunto(s)
Actinina/química , Actinas/química , Músculo Esquelético/química , Actinina/metabolismo , Actinas/metabolismo , Animales , Microscopía , Unión Proteica , Conejos
6.
J Mol Biol ; 263(2): 227-36, 1996 Oct 25.
Artículo en Inglés | MEDLINE | ID: mdl-8913303

RESUMEN

Flexural and torsional rigidities of actin filaments are important factors in cell motility and muscle contraction, where actin filaments serve as mechanical elements. The flexural rigidity has already been determined by directly observing the bending of individual filaments under a microscope, but measurement of the torsional rigidity has been relatively scarce and indirect, because torsion of an actin filament is difficult to visualize. This paper shows that the torsional rigidity can be measured directly by visualizing the torsional Brownian motion of a single actin filament with a novel methodology based on an optical trapping technique. Actin filaments (F-actin) were prepared by polymerizing actin monomers binding Ca2+ ion or Mg2+ ion at the high affinity site. The torsional rigidity of F-Ca(2+)-actin ((8.5(+/- 1.3)) x 10(-26) N m2) was about three times as large as that of F-Mg(2+)-actin ((2.8(+/- 0.3)) x 10(-26) N m2), whereas the flexural rigidity ((6.0(+/- 0.2)) x 10(-26) N m2) was almost independent of the kind of the bound cation. The dynamic structure of F-actin is regulated by the bound metal in an anisotropic manner. The torsional rigidities above, whether of F-Ca(2+)-actin or F-Mg(2+)-actin, are one to two orders of magnitude greater than previous experimental estimates.


Asunto(s)
Actinas/química , Animales , Anisotropía , Elasticidad , Fluorescencia , Conejos
7.
Essays Biochem ; 35: 3-18, 2000.
Artículo en Inglés | MEDLINE | ID: mdl-12471886

RESUMEN

A single molecule of F1-ATPase is by itself a rotary motor in which a central subunit, gamma, rotates against a surrounding stator cylinder made of alpha 3 beta 3 hexamer. Driven by the three beta subunits that hydrolyse ATP sequentially, the motor runs with discrete 120 degrees steps at low ATP concentrations. Over broad ranges of load and speed, the motor produces a constant torque of 40 pN.nm. The mechanical work the motor does in the 120 degrees step, or the work per ATP hydrolysed, is also constant and amounts to 80-90 pN.nm, which is close to the free energy of ATP hydrolysis. Thus this motor can work at near 100% efficiency.


Asunto(s)
Adenosina Trifosfato/metabolismo , Proteínas Motoras Moleculares/fisiología , ATPasas de Translocación de Protón/fisiología , Animales , Humanos
8.
Cell Signal ; 7(7): 659-68, 1995 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-8519595

RESUMEN

Studies were undertaken in an effort to discern possible mechanisms by which the A1 adenosine receptor agonist cyclopentyladenosine (CPA) enhances the norepinephrine-stimulated (NE-stimulated) hydrolysis of phosphoinositides in DDT1-MF2 cells. Measurements of arachidonic acid release revealed similar behaviours to those observed in measurements of phosphoinositide hydrolysis. In the presence of NE, both second messenger responses were potentiated by the addition of CPA, whereas in the absence of NE, CPA had little or no effect on either second messenger. The stimulation and potentiation of both second messenger responses were enhanced in the presence of extracellular calcium, and in each case these effects were persistent over time. For either second messenger system the stimulation by NE and the potentiation by CPA appeared to utilize separate mechanisms as evidenced by the fact that the potentiations by CPA were selectively antagonized by a cAMP analogue or by pertussis toxin, whereas the stimulations by NE were essentially unaffected by these agents. Inhibition of phospholipase A2 (PLA2) also blocked the potentiation of PLC by CPA, without affecting NE-stimulated phosphoinositide hydrolysis. Furthermore, in the presence of CPA, the exogenous administration of PLA2 was found to stimulate phosphoinositide hydrolysis in these cells. These data are consistent with a hypothesis whereby the apparent potentiation of NE-stimulated phosphoinositide hydrolysis by CPA is actually due to the stimulation by CPA of a second pathway of phospholipase C activity which is additive to that of NE. The activation of PLC and PLA2 by NE produces phospholipid products which may play a permissive role in the pathway coupling adenosine A1 receptors to these phospholipases. The formation of lysophosphatidic acid is suggested as one possible mediator of this permissive effect.


Asunto(s)
Ácido Araquidónico/metabolismo , Músculo Liso/metabolismo , Fosfatidilinositoles/metabolismo , Receptores Purinérgicos P1/metabolismo , Adenosina/análogos & derivados , Adenosina/farmacología , Agonistas alfa-Adrenérgicos/farmacología , Animales , Línea Celular , Cricetinae , Sinergismo Farmacológico , Hidrólisis , Músculo Liso/citología , Músculo Liso/efectos de los fármacos , Norepinefrina/farmacología , Fosfolipasas A/antagonistas & inhibidores , Fosfolipasas A2 , Fosfolipasas de Tipo C/metabolismo
9.
Oncogene ; 34(21): 2711-20, 2015 May 21.
Artículo en Inglés | MEDLINE | ID: mdl-25065592

RESUMEN

Metabotropic glutamate 1 (mGlu) receptor has been proposed as a target for the treatment of metastatic melanoma. Studies have demonstrated that inhibiting the release of glutamate (the natural ligand of mGlu1 receptors), results in a decrease of melanoma tumor growth in mGlu1 receptor-expressing melanomas. Here we demonstrate that mGlu1 receptors, which have been previously characterized as oncogenes, also behave like dependence receptors by creating a dependence on glutamate for sustained cell viability. In the mGlu1 receptor-expressing melanoma cell lines SK-MEL-2 (SK2) and SK-MEL-5 (SK5), we show that glutamate is both necessary and sufficient to maintain cell viability, regardless of underlying genetic mutations. Addition of glutamate increased DNA synthesis, whereas removal of glutamate not only suppressed DNA synthesis but also promoted cell death in SK2 and SK5 melanoma cells. Using genetic and pharmacological inhibitors, we established that this effect of glutamate is mediated by the activation of mGlu1 receptors. The stimulatory potential of mGlu1 receptors was further confirmed in vivo in a melanoma cell xenograft model. In this model, subcutaneous injection of SK5 cells with short hairpin RNA-targeted downregulation of mGlu1 receptors resulted in a decrease in the rate of tumor growth relative to control. We also demonstrate for the first time that a selective mGlu1 receptor antagonist JNJ16259685 ((3,4-Dihydro-2H-pyrano[2,3-b]quinolin-7-yl)-(cis-4-methoxycyclohexyl)-methanone) slows SK2 and SK5 melanoma tumor growth in vivo. Taken together, these data suggest that pharmacological inhibition of mGlu1 receptors may be a novel approach for the treatment of metastatic melanoma.


Asunto(s)
Supervivencia Celular/fisiología , Ácido Glutámico/metabolismo , Melanoma/metabolismo , Receptores de Glutamato Metabotrópico/metabolismo , Animales , Muerte Celular/efectos de los fármacos , Muerte Celular/fisiología , Línea Celular Tumoral , Supervivencia Celular/efectos de los fármacos , Humanos , Melanoma/tratamiento farmacológico , Ratones , Ratones Endogámicos C57BL , Ratones Desnudos , Quinolinas/farmacología
10.
J Invest Dermatol ; 114(6): 1184-7, 2000 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-10844564

RESUMEN

Hyaluronan is well known to exist as a water-sorbed macromolecule in the extracellular matrix. We here examined whether hyaluronan exists in the normal stratum corneum. High performance liquid chromatography was used to quantify hyaluronan content in the stratum corneum, epidermis (including stratum corneum), and dermis of mice, with the resulting dry weights being 22.3 +/- 2.9, 15.1 +/- 1.5, and 738.6 +/- 31.6 microg per g, respectively. Normal mouse skin was then labeled with [3H]-glucosamine in an organ culture, and accumulation of [3H]-labeled hyaluronan and its molecular mass were determined separately for the stratum corneum, epidermis, and dermis. In the stratum corneum, [3H]-labeled hyaluronan was accumulated linearly over the 3-d culture period. After the 3-d culture period, the epidermis synthesized twice the amount (expressed as dpm per mg dry weight) of [3H]-labeled hyaluronan as the dermis, whereas the stratum corneum and dermis showed nearly the same content of [3H]-labeled hyaluronan. The molecular mass of [3H]-labeled hyaluronan was highest (>1.0 x 106) in the dermis and clearly lower (<6.0 x 104) in the stratum corneum. Based on these results, we here confirm that hyaluronan is supplied from keratinocytes beneath the stratum corneum layer, and is present in the normal stratum corneum. We speculate that hyaluronan may play a role in moisturizing the stratum corneum and/or regulating its mechanical properties.


Asunto(s)
Ácido Hialurónico/análisis , Piel/química , Animales , Cromatografía DEAE-Celulosa , Cromatografía Líquida de Alta Presión , Glucosamina/metabolismo , Ácido Hialurónico/aislamiento & purificación , Masculino , Ratones , Ratones Pelados , Técnicas de Cultivo de Órganos , Factores de Tiempo , Tritio
11.
J Invest Dermatol ; 108(5): 769-75, 1997 May.
Artículo en Inglés | MEDLINE | ID: mdl-9129231

RESUMEN

UV irradiation induces a variety of cutaneous responses, including disruption of epidermal permeability barrier function, the basis for which is not known. Herein, we investigated the separate roles of hyperproliferation and inflammation in the pathogenesis of UVB-induced barrier disruption. Adult hairless mice were exposed to increasing doses of UVB (1.5-7.5 MED), and transepidermal water loss (TEWL) was monitored daily for up to 7 d. The extent of TEWL increase was dependent on the UVB dose, but with all doses, the increase began after > or =48 h and peaked at 96 h, decreasing by 120 h. Epidermal [(3)H]thymidine incorporation increased at 24 h and peaked at 48 h (570%), preceding the maximal increase in TEWL. Cyclosporin A, methotrexate, 5-fluorouracil, or arabinosylcytosine significantly diminished the UVB-induced TEWL increase. Athymic nude mice also displayed a markedly diminished response to UVB, and DNA synthesis did not increased at 48 h. Transplantation of athymic mice with T-cell-enriched mixed immune cells significantly restored sensitivity to both the UVB-induced hyperproliferation and the barrier defect. Finally, although UVB exposure increased PGE2 levels in whole skin samples (2- to 3-fold within 1-3 h; p < 0.005), this increase was completely blocked by topical indomethacin, and neither topical indomethacin nor topical glucocorticoids blocked development of the barrier abnormality. These results show that (i) UVB produces delayed alteration in barrier function and (ii) both an epidermal proliferative response and thymocyte-mediated events (but not PGE2 production and nonspecific inflammation) appear to contribute to UVB-induced abrogation of the permeability barrier.


Asunto(s)
Permeabilidad de la Membrana Celular/fisiología , Permeabilidad de la Membrana Celular/efectos de la radiación , Rayos Ultravioleta , Corticoesteroides/fisiología , Animales , División Celular , ADN/biosíntesis , Dinoprostona/biosíntesis , Relación Dosis-Respuesta en la Radiación , Hiperplasia , Masculino , Ratones , Ratones Pelados , Ratones Endogámicos BALB C , Ratones Desnudos , Piel/patología , Piel/efectos de la radiación , Timo/citología
12.
Neurobiol Aging ; 16(6): 955-63, 1995.
Artículo en Inglés | MEDLINE | ID: mdl-8622787

RESUMEN

Efficiency of coupling of hippocampal muscarinic receptors to phosphoinositide (PI) turnover was investigated in behaviorally characterized young and aged Long-Evans rats using hippocampal minces and the method of partial receptor alkylation of Furchgott. Densities of the m1, m2, and m3 receptor proteins were determined using specific antibodies and immunoprecipitation. Spatial learning ability was quantified using a water maze. There were no differences in the levels of muscarinic receptor proteins between young and aged (27 months) rats or in rats with impaired spatial learning. The dissociation constant (KD) for the agonist oxotremorine-M and the KD/EC50 ratio, an indicator of receptor-effector coupling efficiency were similar in young and aged rats. However, the maximal PI turnover response to oxotremorine-M was decreased in impaired aged rats and this parameter was highly correlated with the spatial learning index (R = -0.825; p < 0.001). A reduction in effector stimulation in the absence of changes in receptor protein or coupling efficiency suggests that dysfunction in the hippocampal muscarinic receptor systems occurs at the level of phospholipase C or beyond.


Asunto(s)
Envejecimiento/fisiología , Hipocampo/fisiología , Aprendizaje por Laberinto/fisiología , Receptores Muscarínicos/fisiología , Conducta Espacial/fisiología , Animales , Relación Dosis-Respuesta a Droga , Masculino , Oxotremorina/farmacología , Ratas
13.
Mol Neurobiol ; 19(2): 151-79, 1999 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-10371467

RESUMEN

The N-methyl-D-aspartate (NMDA) subtype of glutamate receptors plays a key role in synaptic transmission, synaptic plasticity, synaptogenesis, and excitotoxicity in the mammalian central nervous system. The NMDA receptor channel is formed from two gene products from two glutamate receptor subunit families, termed NR1 and NR2. Although the subunit composition of native NMDA receptors is incompletely understood, electrophysiological studies using recombinant receptors suggest that functional NMDA receptors consist of heteromers containing combinations of NR1, which is essential for channel activity, and NR2, which modulates the properties of the channels. The lack of agonists or antagonists selective for a given subunit of NMDA receptors has made it difficult to understand the subunit expression, subunit composition, and posttranslational modification mechanisms of native NMDA receptors. Therefore, most studies on NMDA receptors that examine regional expression and ontogeny have been focused at the level of the mRNAs encoding the different subunits using northern blotting, ribonuclease protection, and in situ hybridization techniques. However, the data from these studies do not provide clear information about the resultant subunit protein. To directly examine the protein product of the NMDA receptor subunit genes, the development of subunit-specific antibodies using peptides and fusion proteins has provided a good approach for localizing, quantifying, and characterizing the receptor subunits in tissues and transfected cell lines, and to study the subunit composition and the functional effects of posttranslational processing of the NMDA subunits, particularly the phosphorylation profiles of NMDA glutamate receptors.


Asunto(s)
Receptores de N-Metil-D-Aspartato/fisiología , Animales , Regulación de la Expresión Génica , Humanos , Sustancias Macromoleculares , Procesamiento Proteico-Postraduccional , Receptores de Glutamato/química , Receptores de Glutamato/fisiología , Receptores de N-Metil-D-Aspartato/química , Receptores de N-Metil-D-Aspartato/genética
14.
J Immunol Methods ; 123(1): 19-24, 1989 Sep 29.
Artículo en Inglés | MEDLINE | ID: mdl-2794527

RESUMEN

Liposomes incorporating 2,4,6-trinitrophenyl-aminocaproyl-dipalmitoylphosphatidylethanolamine (TNP-cap-DPPE) as a membrane hapten can be lysed by human complement in the presence of anti-TNP antibody. Liposomes were composed of L-alpha-dimyristoylphosphatidylcholine, cholesterol, TNP-cap-DPPE and dicetylphosphate at a molar ratio of 1:1:0.005:0.02. Large unilamellar liposomes were prepared by reverse-phase evaporation with an entrapped marker, carboxyfluorescein, which is self-quenching in liposomes at high concentrations such as 0.2 M. When the marker is released by complement action, a strong fluorescence is produced. The amount of marker released from liposomes is able to quantify complement activity of both the classical and alternative pathways. CL50 is the complement activity obtained by lysis of 50% of the liposomes. The number of CL50 units in sera obtained with liposomes correlates well with those obtained using the hemolytic complement test CH50 (r = 0.98). The advantages of this method include stability of reagents, accuracy, simplicity and speed. In addition, it is well suited for developing an automated system. This method is a useful substitute for the hemolytic assay for determination of human complement activity.


Asunto(s)
Proteínas del Sistema Complemento/análisis , Liposomas , Fluorescencia , Hemólisis , Humanos , Trinitrobencenos/inmunología
15.
Brain Res Mol Brain Res ; 80(2): 123-31, 2000 Sep 15.
Artículo en Inglés | MEDLINE | ID: mdl-11038245

RESUMEN

The effect of post-mortem delay on the stability of the protein subunits that combine to form NMDA and AMPA type glutamate receptors has been assessed in samples of human brain tissue. While most of the subunits (i.e. GluR1, GluR2/3, GluR4, NR1) appear to be stable for up to 18 h post-mortem, the NR2A and NR2B subunits appear to be proteolyzed rapidly following death. These results are consistent with the concept that the proteolytic products of NR2A and NR2B, although at smaller molecular sizes than the full-length protein, are all identifiable on Western blots. Thus, a method is proposed that allows for the estimation of the levels of these labile proteins even in samples obtained up to 18 h post-mortem. Using this method we have estimated the levels of all AMPA and NMDA receptor subunits in selected (i.e. hippocampus, frontal and entorhinal cortex) brain tissue samples obtained from control patients and patients who have died with Alzheimer's disease. Modest decreases in NMDA receptor subunits NR1, NR2A, and NR2B were found in the hippocampus and in frontal cortex while little or no change in any of these subunits were documented in entorhinal cortex. Subunits for AMPA receptors (GluR1, GluR2/3, and GluR4) appeared to show a generalized decrease in all these tissues. As a surrogate marker for overall decreases due to generalized neuronal cell death, levels of neuron-specific enolase were measured in all tissues and were found to be nearly identical in control and Alzheimer's brains.


Asunto(s)
Enfermedad de Alzheimer/patología , Química Encefálica , Encéfalo/patología , Receptores AMPA/análisis , Receptores de N-Metil-D-Aspartato/análisis , Anciano , Especificidad de Anticuerpos , Western Blotting , Femenino , Humanos , Masculino , Persona de Mediana Edad , Receptores AMPA/inmunología , Receptores de N-Metil-D-Aspartato/inmunología , Factores de Tiempo
16.
Invest Radiol ; 33(1): 1-5, 1998 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-9438503

RESUMEN

RATIONALE AND OBJECTIVES: A delayed adverse reaction is one occurring more than an hour after injection of contrast media. The frequency and symptoms of delayed adverse reaction to nonionic contrast media still are not well established. The purpose of the study is to clarify the frequency and symptoms of delayed adverse reactions using nonionic monomeric contrast media. METHODS: Patients studied by computed tomography (CT) were the subject of the investigation. Delayed adverse reactions were compared between the group receiving CT without contrast injection and the group receiving contrast injection. RESULTS: Delayed adverse reactions were noted in 293 of 2370 patients (12.4%) in the group with enhanced CT and in 93 of 907 patients (10.3%) in the group with unenhanced CT. The frequency of delayed adverse reaction to nonionic contrast media was 2.1% (12.4% - 10.3%; P = 0.094). None of the risk factors were related with the incidence of delayed adverse reaction. The most common delayed adverse reaction was a mild skin reaction, which occurred within 24 hours after injection of contrast media. CONCLUSIONS: The frequency of delayed adverse reaction to nonionic monomeric contrast media was 2.1%; the most common reactions were itching and limited urticaria.


Asunto(s)
Medios de Contraste/efectos adversos , Hipersensibilidad Tardía/inducido químicamente , Distribución de Chi-Cuadrado , Femenino , Humanos , Yohexol/efectos adversos , Yopamidol/efectos adversos , Yopamidol/análogos & derivados , Masculino , Factores de Riesgo , Encuestas y Cuestionarios , Tomografía Computarizada por Rayos X
17.
J Biochem ; 111(5): 573-8, 1992 May.
Artículo en Inglés | MEDLINE | ID: mdl-1386357

RESUMEN

Proteolytic inactivation of C4b is a crucial step for regulation of the classical complement pathway. A plasma protease factor I and membrane cofactors, C3b/C4b receptor (CR1) and membrane cofactor protein (MCP), participate in the regulation of cell-bound C4b although the physiological potency of these cofactors remains unknown. We have examined the optimal conditions of the factor I-mediated C4b regulatory system using purified cofactors. CR1 being a cofactor at a cofactor/C4b ratio less than 0.1 (w/w), fluid phase C4b, and methylamine-treated C4 (C4ma) were degraded by factor I into C4bi: minimal Cd4 was generated in the fluid phase. Liposome-bound C4b (LAC4b), on the other hand, was degraded into C4c and C4d. CR1 showed two optimal pHs (6.0 and 7.5) for fluid phase C4b, but one (6.0) for LAC4b, and in both cases low conductivity conditions enhanced the C4bi generation. CR1 cofactor activity was barely influenced by the NP-40 concentration. On the other hand, MCP degraded C4b and C4ma, as a factor I-cofactor, more efficiently into C4c and C4d. Though MCP cofactor activity, like that of CR1, was enhanced under low conductivity conditions, it has only one optimal pH, 6.0, in both fluid and solid phases. Furthermore, as in the case of C3b cleavage, a sufficient NP-40 concentration to solubilize membrane was needed for MCP to express full cofactor activity for C4b, in contrast to CR1. MCP was less potent for C4b inactivation than for C3b inactivation, while CR1 acted as a slightly more effective cofactor for C4b cleavage than for C3b cleavage.(ABSTRACT TRUNCATED AT 250 WORDS)


Asunto(s)
Complemento C4b/antagonistas & inhibidores , Fibrinógeno/metabolismo , Antígenos CD/metabolismo , Vía Clásica del Complemento , Detergentes , Humanos , Concentración de Iones de Hidrógeno , Técnicas In Vitro , Leucocitos/inmunología , Proteína Cofactora de Membrana , Glicoproteínas de Membrana/metabolismo , Octoxinol , Polietilenglicoles , Receptores de Complemento/metabolismo , Receptores de Complemento 3b
18.
J Biochem ; 81(6): 1733-7, 1977 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-19444

RESUMEN

Aspergillus saitoi acid carboxypeptidase hydrolyzed C-terminal peptidyl-L-proline bonds and released the C-terminal proline from Z-Gly-Pro-Leu-Gly-Pro and Z-Gly-Pro at pH 3.3. Proline liberated by the enzymic reaction was measured by a sensitive colorimetric ninhydrin method in glacial acetic acid at 513 nm. A Km value of 1.0 mM and a kcat value of 0.09 s-1 for Z-Gly-Pro-Leu-Gly-Pro hydrolysis, and a Km value of 5.0 mM and a kcat value of 0.0045 s-1 for Z-Gly-Pro hydrolysis were calculated from Lineweaver-Burk plots.


Asunto(s)
Aspergillus/enzimología , Carboxipeptidasas/metabolismo , Prolina , Secuencia de Aminoácidos , Concentración de Iones de Hidrógeno , Cinética , Espectrofotometría
19.
Ann Thorac Surg ; 63(1): 234-6, 1997 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-8993277

RESUMEN

Myxoma of the aortic valve is exceedingly uncommon. In this article, we report a 58-year-old man with myxoma arising from the aortic valve. Aortic valve replacement was performed, and postoperative histologic examination showed myxoma of aortic valve.


Asunto(s)
Neoplasias Cardíacas/diagnóstico , Mixoma/diagnóstico , Válvula Aórtica , Neoplasias Cardíacas/cirugía , Prótesis Valvulares Cardíacas , Humanos , Masculino , Persona de Mediana Edad , Mixoma/cirugía
20.
Brain Res ; 367(1-2): 121-7, 1986 Mar 05.
Artículo en Inglés | MEDLINE | ID: mdl-3008918

RESUMEN

The electrophysiological consequences of in vitro treatment with 6-hydroxydopamine (6-OHDA) were examined in the CA1 region of the rat hippocampal slice. In control slices, norepinephrine (NE) increased the amplitude of the population spike response elicited by synaptic stimulation of hippocampal pyramidal neurons with a threshold of approximately 5 microM. When hippocampal slices were pretreated with 500 microM 6-OHDA for 10 min, perfusion with a subthreshold concentration of NE (0.5 microM) produced responses similar to those observed with a 10-fold higher concentration of NE in untreated slices. Baseline electrophysiological responses were unchanged following the 6-OHDA exposure. The potentiation of the response to NE by in vitro pretreatment with 6-OHDA was accompanied by a greater than 40% decrease in NE content and greater than 90% decrease in [3H]NE accumulation. In vivo treatment with 6-OHDA or N-(2-chloroethyl)-N-ethyl-2-bromobenzylamine hydrochloride (DSP4) also potentiated the electrophysiological response to NE in a manner similar to that observed with acute in vitro 6-OHDA pretreatment. This action does not appear to be due to development of beta-adrenergic receptor supersensitivity, because the apparent potency of isoproterenol in increasing the population spike amplitude was unaffected. These data suggest that the increase in the potency of NE in slices pretreated with 6-OHDA is due to the rapid disruption of the high-affinity NE uptake mechanism characteristic of noradrenergic nerve terminals.


Asunto(s)
Hipocampo/efectos de los fármacos , Hidroxidopaminas/farmacología , Norepinefrina/metabolismo , Fibras Adrenérgicas/efectos de los fármacos , Animales , Bencilaminas/farmacología , AMP Cíclico/metabolismo , Técnicas In Vitro , Masculino , Norepinefrina/análisis , Oxidopamina , Ratas , Ratas Endogámicas , Receptores Adrenérgicos alfa/efectos de los fármacos , Receptores Adrenérgicos beta/efectos de los fármacos
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