Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 83
Filtrar
Más filtros

Banco de datos
País/Región como asunto
Tipo del documento
Intervalo de año de publicación
1.
Clin Radiol ; 73(10): 907.e9-907.e14, 2018 10.
Artículo en Inglés | MEDLINE | ID: mdl-29895387

RESUMEN

AIM: To perform radiology-pathology correlation of the inchworm sign on diffusion-weighted imaging (DWI) in patients with endometrial cancer. MATERIALS AND METHODS: Consecutive patients (345) with histopathologically proven endometrial cancer who underwent preoperative magnetic resonance imaging (MRI), including DWI images, and hysterectomy were included in the present study. The inchworm sign was defined as a hypointense stalk between hyperintense endometrial cancer and hypointense myometrium on DWI images. A genitourinary pathologist reviewed the resected specimen at the site of the inchworm sign. RESULTS: The inchworm sign on DWI images was observed in 32 (9.3%) patients. On T2-weighted images, areas of hypointense stalk on DWI images showed hypointensity in 31 (97%) patients and hyperintensity in one (3%). Among them, the depth of myometrial invasion at histopathology was superficial (<50% myometrial invasion) in 28 (87.5%) patients and deep (≥50% myometrial invasion) in four (12.5%). As a result of histopathological investigation, the hypointense stalk of the inchworm sign was mainly composed of various degrees of stromal proliferation, including smooth muscle cells and metaplastic fibromuscular stroma, with or without intervening endometrial cancer. CONCLUSION: The inchworm sign of endometrial cancer on DWI images usually indicated superficial myometrial invasion and was caused by a stalk composed of stromal proliferation with or without intervening endometrial cancer.


Asunto(s)
Carcinoma Endometrioide/patología , Neoplasias Endometriales/patología , Adulto , Anciano , Anciano de 80 o más Años , Imagen de Difusión por Resonancia Magnética , Femenino , Humanos , Persona de Mediana Edad , Invasividad Neoplásica , Estudios Retrospectivos
2.
Gynecol Oncol ; 137(2): 299-305, 2015 May.
Artículo en Inglés | MEDLINE | ID: mdl-25541259

RESUMEN

OBJECTIVE: In ovarian cancer cases, recurrence after chemotherapy is frequently observed, suggesting the involvement of ovarian cancer stem-like cells (CSCs). The chemoresistance of ovarian clear cell carcinomas is particularly strong in comparison to other epithelial ovarian cancer subtypes. We investigated the relationship between a CSC marker, aldehyde dehydrogenase 1 (ALDH1), and clinical prognosis using ovarian clear cell carcinoma tissue samples. Furthermore, we investigated the antioxidant mechanism by which CSCs maintain a lower reactive oxygen species (ROS) level, which provides protection from chemotherapeutic agents. METHODS: Immunohistochemical staining was performed to examine the CSC markers (CD133, CD44, ALDH1) using ovarian clear cell carcinoma tissue samples (n=81). Clear cell carcinoma cell lines (KOC-7C, OVTOKO) are separated into the ALDH-high and ALDH-low populations by ALDEFLUOR assay and fluorescence-activated cell sorting (FACS). We compared the intracellular ROS level, mRNA level of the antioxidant enzymes and Nrf2 expression of the two populations. RESULTS: High ALDH1 expression levels are related to advanced stage in clear cell carcinoma cases. ALDH1 expression significantly reduced progression free survival. Other markers are not related to clinical stage and prognosis. ALDH-high cells contained a lower ROS level than ALDH-low cells. Antioxidant enzymes were upregulated in ALDH-high cells. ALDH-high cells showed increased expression of Nrf2, a key transcriptional factor of the antioxidant system. CONCLUSIONS: ALDH-positive CSCs might have increased Nrf2-induced antioxidant scavengers, which lower ROS level relevant to chemoresistance in ovarian clear cell carcinoma.


Asunto(s)
Adenocarcinoma de Células Claras/metabolismo , Isoenzimas/metabolismo , Neoplasias Glandulares y Epiteliales/metabolismo , Células Madre Neoplásicas/metabolismo , Neoplasias Ováricas/metabolismo , Especies Reactivas de Oxígeno/metabolismo , Retinal-Deshidrogenasa/metabolismo , Adenocarcinoma de Células Claras/patología , Adulto , Anciano , Anciano de 80 o más Años , Familia de Aldehído Deshidrogenasa 1 , Carcinoma Epitelial de Ovario , Línea Celular Tumoral , Femenino , Humanos , Inmunohistoquímica , Persona de Mediana Edad , Neoplasias Glandulares y Epiteliales/patología , Células Madre Neoplásicas/enzimología , Células Madre Neoplásicas/patología , Neoplasias Ováricas/patología , Pronóstico
3.
J Obstet Gynaecol ; 28(6): 563-6, 2008 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-19003646

RESUMEN

Vaginal fibromyomas (leiomyomas and rhabdomyomas) are rare; approximately 300 cases have been reported in the literature. They usually present as a mass per vaginum or dyspareunia or pressure symptoms on the urinary tract. However, they sometimes have an unusual presentation that is largely responsible for the relative difficulty in preoperative diagnosis. Preoperative imaging and careful examination may help to rule out malignancy. Recurrence occurs infrequently but the practical approach entails immediate careful excision. Surgical excision through the vaginal route has been the traditional approach, but abdominoperineal route may be necessary for huge tumours.


Asunto(s)
Leiomioma/diagnóstico , Rabdomioma/diagnóstico , Neoplasias Vaginales/diagnóstico , Adulto , Femenino , Procedimientos Quirúrgicos Ginecológicos , Humanos , Leiomioma/cirugía , Rabdomioma/cirugía , Neoplasias Vaginales/cirugía
4.
J Clin Invest ; 66(6): 1383-90, 1980 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-6255011

RESUMEN

To elucidate the significance of beta-endorphin in human cerebrospinal fluid (CSF), CSF levels of beta-endorphin-like immunoreactivity (beta-EP-LI) in various diseases were determined by a specific radioimmunoassay and compared with simultaneously determined ACTH-like immunoreactivity (ACTH-LI) levels in CSF. CSF beta-EP-LI and ACTH-LI in the control group, consisting of 5 normal subjects and 19 patients with nonendocrine diseases, were 22.2+/-1.3 and 14.6+/-0.4 fmol/ml, respectively. CSF levels of these peptides in patients with schizophrenia (n = 19) and acromegaly (n = 10) were not significantly different from those in the control group. Patients with Cushing's disease (n = 7) had significantly lower CSF beta-EP-LI and ACTH-LI levels than those in the control group. Four of them showed a parallel increase in CSF beta-EP-LI and CSF ACTH-LI levels after the complete removal of pituitary microadenomas (P < 0.05). Gel chromatography of CSF beta-EP-LI from a normal volunteer, a control patient, and one patient each with catatonia, Nelson's syndrome, Cushing's syndrome (adrenal adenoma), and acromegaly gave similar patterns consisting of three peaks with the elution positions comparable to those of authentic beta-endorphin, beta-lipotropin, and possibly their precursor molecule. Gel chromatographic patterns of CSF beta-EP-LI and ACTH-LI were compared in a normal volunteer. The first peaks of beta-EP-LI and ACTH-LI eluted at the same position and the second peak of ACTH-LI coincided with the elution position of authentic ACTH.CSF beta-EP-LI and ACTH-LI levels determined every 5 min over a period of 80 min in three normal volunteers did not show moment-to-moment variability.A significant correlation (r = 0.75, P < 0.001) was seen between CSF beta-EP-LI and ACTH-LI levels in normal subjects and patients studied (n = 73). This suggests that beta-endorphin and ACTH in human CSF share the common regulatory mechanism in normal and pathologic conditions.


Asunto(s)
Hormona Adrenocorticotrópica/líquido cefalorraquídeo , Endorfinas/líquido cefalorraquídeo , Acromegalia/líquido cefalorraquídeo , Adulto , Síndrome de Cushing/líquido cefalorraquídeo , Femenino , Glucocorticoides/farmacología , Humanos , Masculino , Persona de Mediana Edad , Radioinmunoensayo , Esquizofrenia/líquido cefalorraquídeo
5.
Oncogene ; 18(50): 7034-45, 1999 Nov 25.
Artículo en Inglés | MEDLINE | ID: mdl-10597304

RESUMEN

The PTEN/MMAC1/TEP (PTEN) tumor suppressor gene at 10q23.3 is mutated in multiple types of sporadic tumors including breast cancers and also in the germline of patients with the Cowden's breast cancer predisposition syndrome. The PTEN gene encodes a multifunctional phosphatase capable of dephosphorylating the same sites in membrane phosphatidylinositols phosphorylated by phosphatidylinositol 3'-kinase (PI3K). We demonstrate herein that loss of PTEN function in breast cancer cells results in an increase in basal levels of phosphorylation of multiple components of the P13K signaling cascade as well as an increase in duration of ligand-induced signaling through the P13K cascade. These alterations are reversed by wild-type but not phosphatase inactive PTEN. In the presence of high concentrations of serum, enforced expression of PTEN induces a predominant G1 arrest consistent with the capacity of PTEN to evoke increases in the expression of the p27Kip1 cyclin dependent kinase inhibitor. In the presence of low concentrations of serum, enforced PTEN expression results in a marked increase in cellular apoptosis, a finding which is consistent with the capacity of PTEN to alter the phosphorylation, and presumably function, of the AKT, BAD, p70S6 kinase and GSK3 alpha apoptosis regulators. Under anchorage-independent conditions, PTEN also induces anoikis, a form of apoptosis that occurs when cells are dissociated from the extracellular matrix, which is enhanced in conjunction with low serum culture conditions. Together, these data suggest that PTEN effects on the PI3K signaling cascade are influenced by the cell stimulatory context, and that depending on the exposure to growth factors and other exogenous stimuli such as integrin ligation, PTEN can induce cell cycle arrest, apoptosis or anoikis in breast cancer cells.


Asunto(s)
Apoptosis/genética , Neoplasias de la Mama/patología , Proteínas de Ciclo Celular , División Celular/genética , Genes Supresores de Tumor , Monoéster Fosfórico Hidrolasas/genética , Proteínas Supresoras de Tumor , Neoplasias de la Mama/genética , Inhibidor p27 de las Quinasas Dependientes de la Ciclina , Humanos , Proteínas Asociadas a Microtúbulos/genética , Fosfohidrolasa PTEN , Fosfatidilinositol 3-Quinasas/metabolismo , Fosforilación , Transducción de Señal , Células Tumorales Cultivadas
6.
Clin Cancer Res ; 5(12): 4308-18, 1999 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-10632375

RESUMEN

Lysophosphatidic acid (LPA) is one of the major growth factors in ascites from ovarian cancer patients and appears to play an important role in proliferation, survival, and invasion of ovarian cancer cells. Recently, several groups have shown that Edg-2, which belongs to the G-protein coupled receptor family, is a functional LPA receptor. Northern blot analysis showed that most ovarian cancer cell lines express Edg-2. Edg-2 expression was especially high in the cisplatin-resistant and slowly proliferating 2780cp cell line and was almost absent from the cisplatin-sensitive and rapidly proliferating A2780 cell line. We thus assessed whether Edg-2 could contribute to changes in cell viability, cell proliferation, or cisplatin resistance. Stable overexpression of Edg-2 in A2780 cells induced an exogenous LPA-independent decrease in proliferation but did not alter cisplatin sensitivity. The LPA-independent decrease in growth rate induced by overexpression of Edg-2 could be explained, at least in part, by Edg-2-induced apoptosis rather than by effects on cell cycle progression. In agreement with the results in stably transfected A2780 cells, transient expression of Edg-2 in Jurkat T cells also induced apoptosis. When cells were separated from the extracellular matrix, they underwent a specialized form of apoptosis called anoikis, which is particularly important in survival of cells in the circulation during metastasis. A2780 cells engineered to overexpress Edg-2 were particularly sensitive to anoikis. These observations suggest that Edg-2 may be a negative regulator for ovarian epithelial cell growth and metastasis.


Asunto(s)
Apoptosis , Lisofosfolípidos/fisiología , Proteínas Nucleares/biosíntesis , Neoplasias Ováricas/metabolismo , Neoplasias Ováricas/patología , Receptores de Superficie Celular , Receptores Acoplados a Proteínas G , Factores de Transcripción/biosíntesis , Animales , Antineoplásicos/farmacología , Células COS , División Celular , Cisplatino/farmacología , Resistencia a Antineoplásicos , Femenino , Humanos , Células Jurkat , Lisofosfolípidos/farmacología , Ratones , Proteínas Nucleares/genética , Proteínas Nucleares/fisiología , ARN Mensajero/genética , ARN Mensajero/metabolismo , Receptores del Ácido Lisofosfatídico , Factores de Transcripción/genética , Factores de Transcripción/fisiología , Células Tumorales Cultivadas
7.
J Clin Endocrinol Metab ; 85(9): 3370-5, 2000 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-10999836

RESUMEN

Lysophosphatidic acid (LPA) mediates pleomorphic effects on multiple cell lineages, including an increased proliferative response of ovarian cancer cells both in vitro and in vivo, at least in part through the novel expression of LPA receptors. Thus, LPA hydrolysis is necessary to limit the duration of LPA's action on multiple cell types, including ovarian cancer cells. We determined the principal mechanism of LPA hydrolysis by ovarian cancer cells and its regulation by GnRH, which is known to have antiproliferative actions on ovarian carcinomas. LPA-hydrolyzing activity in cell membranes of ovarian cancer specimens was assessed by measuring the conversion of exogenous [3H-oleoyl]LPA to [3H]oleic acid or mono[3H-oleoyl]glycerol. Approximately 98% of LPA hydrolysis could be accounted for by the dephosphorylation of LPA to yield monoglyceride, with the deacylation reaction accounting for less than 1% of LPA hydrolysis. The phosphatase activity in the plasma membrane ovarian cancer cells was approximately 2.5- and 8-fold higher than those in microsome and homogenate fractions, respectively. The membrane phosphatase was Mg2+ independent and insensitive to inhibition by N-ethylmaleimide, characteristics suggestive of phosphatidic acid phosphatase activity. Incubation of membranes from GnRH receptor-positive ovarian cancer specimens with the GnRH agonist, buserelin, induced a dose-dependent increase in LPA phosphatase activity, with a half-maximal effect occurring with 30 nmol/L buserelin. The stimulatory action of buserelin could be neutralized by displacement of GnRH from its receptor by the GnRH antagonist, antide. The plasma membranes from GnRH receptor-negative ovarian cancer specimens did not respond to GnRH stimulation. LPA phosphatase activity was also increased when the ovarian cancer cell line Caov-3 was exposed to GnRH agonist in intact cells before assay of cell membranes. These data demonstrate that LPA is hydrolyzed in the plasma membrane of ovarian cancer cells by the action of LPA phosphatase and provide initial evidence for functional coupling of LPA phosphatase to GnRH receptor occupancy.


Asunto(s)
Adenocarcinoma de Células Claras/enzimología , Cistadenocarcinoma Mucinoso/enzimología , Cistadenocarcinoma Seroso/enzimología , Hormona Liberadora de Gonadotropina/farmacología , Lisofosfolípidos/metabolismo , Neoplasias Ováricas/enzimología , Monoéster Fosfórico Hidrolasas/metabolismo , Adenocarcinoma de Células Claras/patología , Catálisis , Membrana Celular/enzimología , Membrana Celular/metabolismo , Cistadenocarcinoma Mucinoso/patología , Cistadenocarcinoma Seroso/patología , Femenino , Hormona Liberadora de Gonadotropina/agonistas , Humanos , Cinética , Neoplasias Ováricas/patología , Receptores LHRH/metabolismo , Células Tumorales Cultivadas
8.
Placenta ; 16(5): 461-7, 1995 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-7479617

RESUMEN

A quantitative study on the effects of placental senescence on mitochondrial DNA (mtDNA) was carried out by measuring mitochondrial gene mutation, levels of mRNA for the cytochrome c oxidase subunit I (COI) and of mtDNA in normal placental tissues at different stages. Deleted mtDNA, the expression of COI in mitochondria and the amounts of mtDNA per cell were examined by the polymerase chain reaction, northern blot analysis and southern blot analysis, respectively. No accumulation of mutant mtDNA with a 4977 base pair (bp) deletion was detected in the normal placenta during pregnancy. There appeared to be a gradual increase of COI mRNA as pregnancy progressed, while the ratio of mtDNA to total DNA in human placenta tended to decrease with gestation. These results indicate that placental ageing is not associated with the accumulation of mtDNA mutation with the 4977 bp deletion or markedly reduced expression of the mitochondrial genome.


Asunto(s)
ADN Mitocondrial/genética , Complejo IV de Transporte de Electrones/genética , Regulación del Desarrollo de la Expresión Génica/fisiología , Regulación Enzimológica de la Expresión Génica/fisiología , Placenta/metabolismo , Secuencia de Bases , Femenino , Eliminación de Gen , Humanos , Datos de Secuencia Molecular , Embarazo , Valores de Referencia
9.
Int J Oncol ; 5(6): 1379-83, 1994 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-21559725

RESUMEN

Prolactin (PRL) blocks the mitogenic activity of the endometrium via a PRL receptor (PRL-R)-mediated mechanism (Proc Soc Exp Biol Med 203: 117, 1993, ibid 205: 140, 1994). To elucidate the molecular mechanism of the antimitogenic action of PRL, we examined the PRL receptor-linked tyrosine kinase and phosphotyrosine phosphatase (PTP), known to constitute the signaling of cell growth, within isolated plasma membranes from endometrium and endometrial carcinoma. Surgically removed human endometrial carcinomas and normal endometrium were examined. PRL receptor mRNA was determined by reverse transcription-polymerase chain reaction using oligonucleotide primers synthesized according to the published human PRL receptor sequence. Phosphotyrosine-containing membrane proteins were analyzed using antiphosphotyrosine antibody in Western blots. Plasma membrane-associated PTP activity was examined using the synthetic substrate para-nitrophenyl phosphates (p Npp) in a spectrophotometric assay, PRL receptor mRNA was detected in all endometria tested, 7 of 9 samples of well-differentiated adenocarcinoma, 7 of 8 of poorly-differentiated adenocarcinoma. In plasma membrane isolated from PRL receptor mRNA-positive specimens, PRL induced dose-dependent (i) decrease in the level of tyrosine-phosphorylated protein and (ii) inhibition of PTP activity in the presence of nonhydrolyzable GTP. PRL alone showed no hormonal action. PRL may decrease the phosphotyrosine level in protein substrates through block of tyrosine kinase. The PRL receptor-linked tyrosine phosphorylation may be mediated by a GTP-binding protein. The inhibition of the tyrosine kinase suggests an involvement of this enzyme in the growth-inhibiting action of PRL.

10.
Ann N Y Acad Sci ; 905: 188-208, 2000 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-10818454

RESUMEN

Levels of lysophosphatidic acid (LPA) and lysophosphatidylcholine (LPC) are elevated in the plasma and ascites of ovarian cancer patients, but not in most other tumor types. LPA increases cell proliferation, cell survival, resistance to cisplatin, cell shrinkage, and production of vascular endothelial growth factor, urokinase plasminogen activator, and LPA itself in ovarian cancer cells, but not in normal ovarian surface epithelial cells. PSP24 and members of the endothelial differentiation gene (EDG) family (EDG1, EDG2, EDG4, and EDG7) of G protein-coupled receptors mediate LPA signaling. Ovarian cancer cell lines do not express EDG1 mRNA, have variable EDG2 mRNA and protein levels, and frequently exhibit levels of EDG4 mRNA and protein, suggesting that EDG4 may contribute to the deleterious effects of LPA in ovarian cancer. In contrast, activation of the EDG2 LPA receptor on ovarian cancer cells may lead to apoptosis and counter the effects of other LPA receptors. Thus, the development of agonists and antagonists for the appropriate spectrum of LPA receptors may alter proliferation, apoptosis, or response to therapy of ovarian cancer cells. Indeed, over 60% of all current drugs target the G protein-coupled family of receptors, making the LPA receptor family a "drugable" target. LPC, although not as thoroughly studied, increases cellular proliferation and mediates multiple other functions through unique signaling pathways.


Asunto(s)
Sustancias de Crecimiento/fisiología , Lisofosfolípidos/fisiología , Neoplasias Ováricas/patología , Ascitis/metabolismo , Femenino , Regulación de la Expresión Génica/fisiología , Humanos , Lisofosfolípidos/antagonistas & inhibidores , Lisofosfolípidos/metabolismo , Metástasis de la Neoplasia , Neoplasias Ováricas/terapia , Ovario/metabolismo , Receptores de Superficie Celular/metabolismo , Transducción de Señal
11.
Obstet Gynecol ; 84(2): 283-8, 1994 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-8041548

RESUMEN

OBJECTIVE: To elucidate the possible relation between mitochondrial gene expression and placental dysfunction. METHODS: We measured the activity of cytochrome c oxidase and the expression of cytochrome oxidase subunit I in mitochondria from human placentas of women whose gestations were appropriate for gestational age (AGA) and those with preeclampsia. In addition, the amounts of normal mtDNA and deleted mitochondrial DNA were examined in the two groups by Southern blot analysis and polymerase chain reaction, respectively. RESULTS: Cytochrome c oxidase activity and expression of cytochrome oxidase subunit I were significantly lower in the preeclamptic group than in the AGA group. There were no differences between the groups in the amounts of mitochondrial DNA. In addition, no mutant mitochondrial DNA with a 4977-base pair deletion was detected in the two groups. CONCLUSION: These results suggest that reduced expression of the mitochondrial gene is involved in placental dysfunction in preeclamptic pregnancy.


Asunto(s)
ADN Mitocondrial/genética , Complejo IV de Transporte de Electrones/genética , Mitocondrias/metabolismo , Placenta/metabolismo , Preeclampsia/genética , ARN Mensajero/genética , Actinas/metabolismo , Adulto , Secuencia de Bases , ADN Mitocondrial/metabolismo , Complejo IV de Transporte de Electrones/biosíntesis , Femenino , Regulación de la Expresión Génica , Humanos , Datos de Secuencia Molecular , Placenta/fisiopatología , Reacción en Cadena de la Polimerasa , Preeclampsia/metabolismo , Embarazo , ARN Mensajero/metabolismo , Eliminación de Secuencia
12.
Brain Res ; 367(1-2): 162-8, 1986 Mar 05.
Artículo en Inglés | MEDLINE | ID: mdl-2870768

RESUMEN

Electroconvulsive shock (ECS) evoked a short-latencied elevation in the hot plate and tail flick response latencies. Naloxone administered before or immediately after ECS produced a dose-dependent antagonism of the antinociceptive effect measured at 7 min but not at 2 min after ECS. Intrathecally administered propranolol, methysergide or naloxone had no effect when administered either before or after ECS. In contrast, phentolamine given intrathecally produced a significant antagonism of the reflex latencies otherwise elevated after ECS. These effects appear mediated by an alpha 2-receptor as they were more readily antagonized by yohimbine than prazosin. These observations suggest the presence of two systems, one supraspinal and opioid in character and the other adrenergic with spinal receptors. The differential effects of injecting naloxone before and after ECS suggests that the opioid system is activated between 2 and 5 min after the ECS, while the adrenergic system, as examined by the effects of intrathecal alpha- and alpha 2-antagonists, appears to be activated immediately after the application of the ECS.


Asunto(s)
Analgesia , Sistema Nervioso Central/fisiopatología , Electrochoque , Neurotransmisores/fisiología , Dolor/fisiopatología , Animales , Endorfinas/fisiología , Masculino , Norepinefrina/fisiología , Ratas , Ratas Endogámicas , Reflejo Anormal/fisiopatología , Serotonina/fisiología , Transmisión Sináptica
13.
Brain Res ; 406(1-2): 207-14, 1987 Mar 17.
Artículo en Inglés | MEDLINE | ID: mdl-3032357

RESUMEN

Using cortical cups in chloralose-urethanized rats, the in vivo release of cholecystokinin-like immunoreactivity (CCK-LI) from cerebral cortex was examined. Resting levels of cholecystokinin-like immunoreactivity ranged from 20 to 30 pg/20 min sample. The addition of potassium (40 mM) in excess, resulted in a highly significant elevation in the levels of CCK-LI in the cortical superfusate. Deletion of calcium and the substitution of cobalt (10 mM), resulted in a significant reduction in both resting release and the release otherwise evoked by the addition of potassium. Focal electrical stimulation of the cortex (20 Hz), resulted in a significant (1.9 +/- 0.2-fold, n = 8) increase in the levels of CCK-LI. The addition of glutamate (10(-6)-10(-4) M) of kainic acid (10(-8)-10(-6) M), also resulted in significant elevations in the levels of CCK-LI. The co-administration of a putative glutamate receptor antagonist, kynurenic acid (10(-4) M) resulted in a significant reduction in the levels of release otherwise evoked by the addition of glutamate, but not by electrical stimulation. The addition of GABA (10(-5)-10(-3) M) resulted in a dose-dependent decrease in the resting release of CCK-LI, and the release evoked by glutamate. Picrotoxin (10(-6)-10(-4) M), resulted in a highly significant increase in the levels of CCK-LI in the cortical effluent. These results are consistent with a tonic GABAergic inhibition of CCK-releasing neurons. The treatment of the animal with diazepam (30 mg/kg, i.p.) also resulted in a significant reduction in resting release and the release otherwise evoked by focal cortical stimulation.


Asunto(s)
Corteza Cerebral/metabolismo , Colecistoquinina/metabolismo , Receptores de GABA-A/fisiología , Receptores de Neurotransmisores/fisiología , Aminoácidos/farmacología , Animales , Calcio/fisiología , Diazepam/farmacología , Masculino , Picrotoxina/farmacología , Potasio/farmacología , Ratas , Ratas Endogámicas , Receptores de Glutamato , Tetrodotoxina/farmacología
14.
Pancreas ; 21(3): 257-61, 2000 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-11039469

RESUMEN

We studied the role of the increase in the calcium concentration in pure pancreatic juice of alcoholic noncalcified chronic pancreatitis. Pure pancreatic juice was obtained endoscopically. The pancreatic juice from patients with chronic pancreatitis was adjusted to pH 7.5; then the calcium concentration was adjusted to 0.4, 2.9, 5.4, or 10.4 mmol/L. Artificial precipitates were produced by incubation of the samples at 37 degrees C for 6 hours. Proteins in the artificial precipitates were separated by sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE), and the protein patterns were compared with the patterns of natural protein plugs from patients with chronic pancreatitis. The amount of the precipitate increased as the added calcium increased. The protein patterns of SDS-PAGE of the artificial precipitates were similar to those of protein plugs. Albumin, a-amylase, lipase, trypsinogen, and chymotrypsinogen were identified by immunoblotting both in the precipitate and in the protein plug. The increased calcium concentrations in pancreatic juice induced the formation of precipitates whose protein composition was similar to that of protein plugs. An increased calcium concentration in human pancreatic juice may play an important role in the pathogenesis of protein plugs.


Asunto(s)
Calcio/análisis , Jugo Pancreático/química , Pancreatitis Alcohólica/metabolismo , Proteínas/análisis , Adulto , Anciano , Albúminas/análisis , Precipitación Química , Enfermedad Crónica , Quimotripsinógeno/análisis , Electroforesis en Gel de Poliacrilamida , Humanos , Concentración de Iones de Hidrógeno , Immunoblotting , Lipasa/análisis , Masculino , Persona de Mediana Edad , Tripsinógeno/análisis , alfa-Amilasas/análisis
15.
Neurosurgery ; 34(6): 1047-51; discussion 1051, 1994 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-8084389

RESUMEN

The effects of phenytoin, carbamazepine and valproic acid on alterations in sodium-potassium-adenosine triphosphatase activity during ischemia were studied in the rat brain. Pretreatment with phenytoin and carbamazepine prevented a reduction of this activity, which, without either treatment, was observed in the cerebral hemisphere exposed to 30-minute ischemia resulting from unilateral middle cerebral artery occlusion. Valproic acid, on the other hand, did not principally affect the ischemic impairment of this membrane-bound enzyme activity. These results lend support to the previously proposed use of phenytoin in cerebral ischemia, but also suggest the therapeutic availability of another common anticonvulsant, carbamazepine, for treatment of the insult.


Asunto(s)
Carbamazepina/farmacología , Infarto Cerebral/enzimología , Fenitoína/farmacología , ATPasa Intercambiadora de Sodio-Potasio/metabolismo , Ácido Valproico/farmacología , Animales , Corteza Cerebral/irrigación sanguínea , Corteza Cerebral/patología , Infarto Cerebral/patología , Relación Dosis-Respuesta a Droga , Masculino , Premedicación , Ratas , Ratas Wistar
16.
Oncol Rep ; 1(6): 1131-2, 1994 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-21607505

RESUMEN

Postsurgical precise correlation was examined in 48 patients with an invasive carcinoma of the cervix in International Federation of Gynecology and Obstetrics (FIGO) clinical stage IIb. Of the 48 cases, 18 cases were overestimated; in which inflammatory parametrial changes and endophytic tumor growth were seen. Six lesions clinically underestimated were associated with superficial invasion into the rectal or bladder muscle. Resultant precise correlation was available in the remainder (24 cases).

17.
Oncol Rep ; 2(4): 625-31, 1995 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-21597789

RESUMEN

Gonadotropin-releasing hormoen (Gn-RH) analogs have been used in the therapy of the endocrine-dependent cancers including the repductive tract-originated tumors. Gn-RH receptor and its transmembrane signaling pathways have been demonstrated in a high proportion of these tumors. The demonstration of existence of receptors for a hormone can better predict hormonal dependency, and might be a first step towards an effective hormonal treatment. These findings suggest the merit of further therapeutic investigations of Gn-RH analogs alone or in combination with traditional therapies in the management of Gn-RH receptor-positive tumors.

18.
Oncol Rep ; 2(6): 1055-7, 1995 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-21597852

RESUMEN

The phosphotyrosine phosphatase (PTPase) decreases the level of phosphotyrosine of intracellular protein substrates, thereby reversing the action of tyrosine phosphorylation to promote cell growth and differentiation. We determined the activities of PTPases in normal and cancerous tissues of the endometrium. The PTPase activity was determined with the synthetic substrate p-nitrophenyl in a spectrophotometric assay. Over 90% of the activity was particulate and the values in proliferative- and secretory-phase endometria and endometrial carcinomas fell within a similar range. This work demonstrates the existence of PTPase activity, counterbalancing the growth-promoting effects of tyrosine kinases, in endometrial carcinoma.

19.
Oncol Rep ; 1(6): 1123-6, 1994 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-21607503

RESUMEN

Expression of the c-erbB-2 product (p185(c-erbB-2)) was examined in plasma membrane isolations from 14 uterine endometrial carcinomas and 3 normal endometrial tissues. Overexpression of p185(c-erbB-2) was found in 8 of 9 endometrial carcinomas of stages III and IV and in none of 5 early stage specimens, when compared with the level in normal endometrial tissues. The expression of p185(c-erbB-2) was independent of histological grade. When the p185(c-erbB-2) immunoprecipitated with anti-p185(c-erbB-2) antibodies was exposed to adenosine triphosphate, enhanced self-phosphorylation occurred more frequently in specimens from the tumors carrying p185(c-erbB-2) overexpression. These findings demonstrated positive correlation between disease spread, p185(c-erbB-2) expression and autophosphorylation of p185(c-erbB-2) in human endometrial carcinoma. The prognostic value of these observations awaits continued study.

20.
J Neurosurg ; 60(4): 861-3, 1984 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-6707760

RESUMEN

The authors describe an indwelling intraluminal shunt for carotid endarterectomy. The device is equipped with balloons at both ends to prevent bleeding and to hold the tube in place. The design permits use of a small tube which facilitates insertion, and prevents intimal damage and limitation of exposure of arterial plaque.


Asunto(s)
Arterias Carótidas/cirugía , Endarterectomía/instrumentación , Humanos
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA