195 results on '"Guibert B"'
Search Results
152. Pulmonary mucormycosis in a diabetic patient.
- Author
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Vincent L, Biron F, Jardin P, Piens M, Dannaoui E, Isaac S, Guibert B, and Pacheco Y
- Subjects
- Humans, Male, Middle Aged, Diabetes Complications, Lung Diseases, Fungal complications, Mucormycosis complications
- Abstract
We present the case of a 54 year-old male from Moldavia with diabetes mellitus (type II diabetic), admitted to hospital in January 1999, with ketoacidosis and consolidation of the lower left lobe. The diagnosis of mucormycosis was confirmed by identification of large, nonseptate hyphae of the order Mucorales. A strain of Rhizopus oryzae (Rhizopus arrhizus) was isolated from culture on sabouraud medium. The patient was treated by systemic amphotericin B, associated with surgical debridement (lobectomy). The treatment with amphotericin B was stopped after ten days and the patient was completely asymptomatic and returned to Moldavia. Mucormycoses are rare, and tend to be encountered in individuals with predisposing factors such as malignant blood disorders (immunocompromised patients) or diabetes mellitus. Prognosis is poor, resembling infection with Aspergillus, despite aggressive treatment as in the present case. The gravity of the condition can be accounted for by the thrombotic and necrosing nature of the fungal invasion of lung vessels.
- Published
- 2000
153. Glutamate induces phosphorylation of Elk-1 and CREB, along with c-fos activation, via an extracellular signal-regulated kinase-dependent pathway in brain slices.
- Author
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Vanhoutte P, Barnier JV, Guibert B, Pagès C, Besson MJ, Hipskind RA, and Caboche J
- Subjects
- Animals, Brain pathology, Corpus Striatum pathology, Extracellular Space, Gene Expression Regulation, Glutamic Acid pharmacology, Kinetics, MAP Kinase Kinase 1, Male, Mitogen-Activated Protein Kinase 1, Mitogen-Activated Protein Kinase 3, Phosphorylation, Protein Serine-Threonine Kinases metabolism, Protein-Tyrosine Kinases metabolism, Proto-Oncogene Proteins c-raf metabolism, Rats, Rats, Sprague-Dawley, ets-Domain Protein Elk-1, Brain metabolism, Calcium-Calmodulin-Dependent Protein Kinases metabolism, Cyclic AMP Response Element-Binding Protein metabolism, DNA-Binding Proteins, Glutamic Acid metabolism, Mitogen-Activated Protein Kinase Kinases, Mitogen-Activated Protein Kinases, Proto-Oncogene Proteins metabolism, Proto-Oncogene Proteins c-fos genetics, Signal Transduction, Transcription Factors, Transcriptional Activation
- Abstract
In cell culture systems, the TCF Elk-1 represents a convergence point for extracellular signal-related kinase (ERK) and c-Jun N-terminal kinase/stress-activated protein kinase (JNK/SAPK) subclasses of mitogen-activated protein kinase (MAPK) cascades. Its phosphorylation strongly potentiates its ability to activate transcription of the c-fos promoter through a ternary complex assembled on the c-fos serum response element. In rat brain postmitotic neurons, Elk-1 is strongly expressed (V. Sgambato, P. Vanhoutte, C. Pagès, M. Rogard, R. A. Hipskind, M. J. Besson, and J. Caboche, J. Neurosci. 18:214-226, 1998). However, its physiological role in these postmitotic neurons remains to be established. To investigate biochemically the signaling pathways targeting Elk-1 and c-fos in mature neurons, we used a semi-in vivo system composed of brain slices stimulated with the excitatory neurotransmitter glutamate. Glutamate treatment leads to a robust, progressive activation of the ERK and JNK/SAPK MAPK cascades. This corresponds kinetically to a significant increase in Ser383-phosphorylated Elk-1 and the appearance of c-fos mRNA. Glutamate also causes increased levels of Ser133-phosphorylated cyclic AMP-responsive element-binding protein (CREB) but only transiently relative to Elk-1 and c-fos. ERK and Elk-1 phosphorylation are blocked by the MAPK kinase inhibitor PD98059, indicating the primary role of the ERK cascade in mediating glutamate signaling to Elk-1 in the rat striatum in vivo. Glutamate-mediated CREB phosphorylation is also inhibited by PD98059 treatment. Interestingly, KN62, which interferes with calcium-calmodulin kinase (CaM-K) activity, leads to a reduction of glutamate-induced ERK activation and of CREB phosphorylation. These data indicate that ERK functions as a common component in two signaling pathways (ERK/Elk-1 and ERK/?/CREB) converging on the c-fos promoter in postmitotic neuronal cells and that CaM-Ks act as positive regulators of these pathways.
- Published
- 1999
- Full Text
- View/download PDF
154. Human immunodeficiency virus type 1 and its coat protein gp120 induce apoptosis and activate JNK and ERK mitogen-activated protein kinases in human neurons.
- Author
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Lannuzel A, Barnier JV, Hery C, Huynh VT, Guibert B, Gray F, Vincent JD, and Tardieu M
- Subjects
- Astrocytes enzymology, Astrocytes pathology, Cells, Cultured, Embryo, Mammalian, Enzyme Activation, Humans, MAP Kinase Kinase 4, Microglia enzymology, Microglia pathology, Phosphorylation, Signal Transduction, Time Factors, AIDS Dementia Complex enzymology, AIDS Dementia Complex pathology, Apoptosis, Calcium-Calmodulin-Dependent Protein Kinases metabolism, HIV Envelope Protein gp120 metabolism, HIV-1 metabolism, JNK Mitogen-Activated Protein Kinases, Mitogen-Activated Protein Kinase Kinases, Mitogen-Activated Protein Kinases metabolism, Nerve Tissue Proteins metabolism, Neurons enzymology, Neurons pathology, Protein Kinases metabolism
- Abstract
Detection of apoptotic neurons and microglial cells in the brains of human immunodeficiency virus type 1 (HIV-1)-infected patients has suggested that programmed cell death may be implicated in the physiopathology of HIV-1 encephalopathy. To analyze in vitro the intracellular signals induced by HIV-1 in human neurons and the associated neuronal death, we tested cultured human central nervous system (CNS) cells for apoptosis induced by HIV-1 and gp120 and for signaling pathways activated by gp120. HIV-1 and gp120 induced apoptosis of neurons and microglial cells but not of astrocytes or transformed microglial cells. Gp120 activated c-Jun N-terminal kinase (JNK) and p42 extracellular-regulated kinase (ERK) in primary CNS cells, with an early peak of activation at 2 to 5 minutes that was not present when pure microglial or astrocyte cultures were tested, followed by a late and sustained activation (10 and 60 minutes) in primary and enriched glial cell cultures as well as in transformed microglial cells. This demonstrates that gp120 could be an effector of HIV-1-induced apoptosis in the CNS and act directly on neuronal and glial cells.
- Published
- 1997
- Full Text
- View/download PDF
155. [Long-term outcome of 72 patients surgically treated for stage II non-small cell bronchial cancer, between 1982 and 1989].
- Author
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Brunel-Crova J, Guibert B, Mulsant P, Souquet PJ, Gérinière L, Bombaron P, and Bernard JP
- Subjects
- Adult, Aged, Carcinoma, Non-Small-Cell Lung pathology, Carcinoma, Non-Small-Cell Lung secondary, Cause of Death, Chemotherapy, Adjuvant, Disease-Free Survival, Female, Humans, Lung Neoplasms pathology, Lymph Nodes pathology, Lymphatic Metastasis pathology, Male, Middle Aged, Neoplasm Recurrence, Local pathology, Neoplasm Staging, Neoplasms, Multiple Primary pathology, Neoplasms, Second Primary pathology, Pneumonectomy, Radiotherapy, Adjuvant, Retrospective Studies, Survival Rate, Treatment Outcome, Carcinoma, Non-Small-Cell Lung surgery, Lung Neoplasms surgery
- Abstract
We report a 72 patients trial, who had surgical treatments for non small cell lung cancer, stage II (T1N1, T2N1). In our retrospective study, the overall 5-years survival is 44%, with a 24-month median survival. 45% of the patients have recurrence mainly due to distant metastasis. State II appears to be an heterogeneous group. As shown in other studies, the presence of hilar nodes (N1H) seems to be linked with a pejorative outcome. In our series, the survival associated with Lobar N1 (N1L) disease is the same as the survival of Hilar N1 disease, but the initial sites of recurrence differ. The interest of a postchirurgical treatment is controversial. The postoperative radiotherapy reduces the local recurrence without increasing the survival. The chemotherapy treatment is debatable and several studies are under way. We reviewed the different causes of death. The appearance of second cancer in the cured patients is very frequent.
- Published
- 1997
156. Clear cell tumor of the lung: an immunohistochemical and ultrastructural study supporting a pericytic differentiation.
- Author
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Lantuejoul S, Isaac S, Pinel N, Negoescu A, Guibert B, and Brambilla E
- Subjects
- Adenocarcinoma, Clear Cell metabolism, Adenocarcinoma, Clear Cell ultrastructure, Aged, Antigens, CD34 biosynthesis, Antigens, Neoplasm biosynthesis, Cell Differentiation, Collagen biosynthesis, Humans, Immunohistochemistry, Lung Neoplasms metabolism, Lung Neoplasms ultrastructure, Male, Membrane Glycoproteins, Muscle, Smooth, Vascular ultrastructure, Neoplasm Proteins biosynthesis, Proteins, Vimentin biosynthesis, gp100 Melanoma Antigen, Adenocarcinoma, Clear Cell pathology, Lung Neoplasms pathology, Muscle, Smooth, Vascular cytology
- Abstract
Clear cell tumor ("sugar tumor") of the lung is a rare benign lesion with unclear histogenesis. It is composed of large cells with a clear cytoplasm rich in glycogen, blended with an abundant network of sinusoid-type vessels. We report two cases of sugar tumor, one of these lacking clearly demonstrable glycogen storage. In both, the tumor cells lacked keratin expression and were positive for vimentin and HMB 45, an antibody recognizing perivascular or myoid cell proliferation such as lymphangioleiomyomatosis and angiomyolipoma. The tumor cells were also immunoreactive for an endothelial cell marker, CD 34, but negative for Factor VIII or smooth muscle actin. Intercellular deposition of basal-like material was immunostained with Type IV collagen. At ultrastructural examination of one of these cases, tumor cells showing features of pericytes or poorly differentiated perivascular leiomyocytes encased in basement material were observed in close association with endothelial cells; their cytoplasm contained numerous membrane-bound glycogen and pinocytic vesicles. We conclude that on the basis of immunohistochemical and ultrastructural phenotype, sugar tumor presents pericytic features and that glycogen storage is not a constant feature of these benign tumors.
- Published
- 1997
157. [Endovascular closure of a foramen ovale after a right pneumonectomy].
- Author
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Bombaron P, Lemaire C, Souquet PJ, Gériniere L, Bourlon D, Guibert B, Voloch A, and Bernard JP
- Subjects
- Cardiac Catheterization, Fatal Outcome, Heart Septal Defects, Atrial diagnostic imaging, Humans, Male, Middle Aged, Prostheses and Implants, Radiography, Angioplasty, Carcinoma, Non-Small-Cell Lung surgery, Heart Septal Defects, Atrial etiology, Heart Septal Defects, Atrial surgery, Lung Neoplasms surgery, Pneumonectomy adverse effects
- Abstract
We report the case of a patient, 62-year-old, with a non small cell lung cancer treated by right pneumonectomy followed by chemo and radiotherapy. After surgery appeared a refractory hypoxemia increasing with supine position. Cardiac catheterism showed a right left shunt by reopening of the "foramen ovale". We have performed foramen's occlusion by endovascular method with prothetic material with good result until the death, 14 months later, by neoplasic evolution.
- Published
- 1997
158. [Malignant mesothelioma of the pleura following radiotherapy of Hodgkin disease].
- Author
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Falchero L, Coiffier B, Guibert B, Souquet PJ, Isaac Pinet S, and Trillet-Lenoir V
- Subjects
- Antineoplastic Combined Chemotherapy Protocols therapeutic use, Female, Follow-Up Studies, Hodgkin Disease drug therapy, Humans, Mechlorethamine administration & dosage, Mesothelioma pathology, Mesothelioma surgery, Middle Aged, Neoplasms, Radiation-Induced pathology, Neoplasms, Radiation-Induced surgery, Pleural Neoplasms pathology, Pleural Neoplasms surgery, Prednisone administration & dosage, Procarbazine administration & dosage, Treatment Outcome, Vincristine administration & dosage, Hodgkin Disease radiotherapy, Mesothelioma etiology, Neoplasms, Radiation-Induced etiology, Pleural Neoplasms etiology
- Abstract
Second neoplasms following chemotherapy and radiotherapy for Hodgkin's disease have been extensively described, including acute myeloblastic leukemia, non Hodgkin's lymphomas and various solid tumors. We report malignant pleural mesothelioma occurring 17 years after mantle radiotherapy and MOPP chemotherapy for Hodgkin's disease. According to Cahan's criteria, this mesothelioma may be considered as treatment-related. Fourteen similar cases have been previously published. Post-radiation mesothelioma might be characterised by limited stage at diagnosis and might be surgically removed at presentation.
- Published
- 1996
159. Rapid stimulation of striatal dopamine synthesis by estradiol.
- Author
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Pasqualini C, Olivier V, Guibert B, Frain O, and Leviel V
- Subjects
- 3,4-Dihydroxyphenylacetic Acid analysis, Animals, Aromatic Amino Acid Decarboxylase Inhibitors, Corpus Striatum metabolism, Dopamine metabolism, Enzyme Inhibitors pharmacology, Female, Hydrazines pharmacology, Levodopa analysis, Ovariectomy, Rats, Corpus Striatum drug effects, Dopamine biosynthesis, Estradiol pharmacology
- Published
- 1996
- Full Text
- View/download PDF
160. [Spontaneous hydro-pneumothorax disclosing malignant mesothelioma. Apropos of 2 cases].
- Author
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Kolber C, Souquet PJ, Gérinière L, Bombaron P, Mulsant P, Guibert B, Pinet-Isaac S, and Bernard JP
- Subjects
- Adult, Humans, Male, Middle Aged, Recurrence, Hydrothorax etiology, Mesothelioma complications, Pleural Neoplasms complications, Pneumothorax etiology
- Abstract
We report the cases of two males who presented with spontaneous complete unilateral pneumothorax with ipisilateral liquid effusion. Neither had a history of previous respiratory disease. In both cases chest tube drainage resulted in recurrence of pneumothorax with chronic illness requiring surgical exploration. The surgery revealed a malignant pleural mesothelioma by histological examination. Thus, spontaneous pneumothorax, particularly with abondant effusion can be a revealing symptom of malignant pleural mesothelioma.
- Published
- 1996
161. Acute stimulatory effect of estradiol on striatal dopamine synthesis.
- Author
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Pasqualini C, Olivier V, Guibert B, Frain O, and Leviel V
- Subjects
- 3,4-Dihydroxyphenylacetic Acid metabolism, Animals, Enzyme Inhibitors pharmacology, Female, Hydrazines pharmacology, Rats, Rats, Wistar, Tyrosine 3-Monooxygenase antagonists & inhibitors, Tyrosine 3-Monooxygenase metabolism, Corpus Striatum drug effects, Corpus Striatum metabolism, Dopamine biosynthesis, Estradiol pharmacology
- Abstract
The acute effect of physiological doses of estradiol (E2) on the dopaminergic activity in the striatum was studied. In a first series of experiments, ovariectomized rats were injected with 17 alpha or 17 beta E2 (125, 250, or 500 ng/kg of body weight, s.c.), and in situ tyrosine hydroxylase (TH) activity (determined by DOPA accumulation in the striatum after intraperitoneal administration of NSD 1015) was quantified. A dose-dependent increase in striatal TH activity was observed within minutes after 17 beta (but not 17 alpha) E2 treatment. To examine whether E2 acts directly on the striatum, in a second series of experiments, anesthetized rats were implanted in the striatum with a push-pull cannula supplied with an artificial CSF containing [3H]tyrosine. The extracellular concentrations of total and tritiated dopamine (DA) and 3,4-dihydroxyphenylacetic acid (DOPAC) were measured at 20-min intervals. Addition of 10(-9) M 17 beta (but not 17 alpha) E2 to the superfusing fluid immediately evoked an approximately 50% increase in [3H]DA and [3H]DOPAC extracellular concentrations, but total DA and DOPAC concentrations remained constant. This selective increase in the newly synthesized DA and DOPAC release suggested that E2 affects DA synthesis rather than DA release. Finally, to determine whether this rapid E2-induced stimulation of DA synthesis was a consequence of an increase in TH level of phosphorylation, the enzyme constant of inhibition by DA (Ki(DA)) was calculated. Incubation of striatal slices in the presence of 10(-9) M 17 beta (but not 17 alpha) E2 indeed evoked an approximate twofold increase in the Ki(DA) of one form of the enzyme.(ABSTRACT TRUNCATED AT 250 WORDS)
- Published
- 1995
- Full Text
- View/download PDF
162. TH mRNA over-expression in rats with chronic excitotoxic striatal lesions.
- Author
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Hantraye P, Guibert B, Biguet NF, Lavergne A, and Leviel V
- Subjects
- 3,4-Dihydroxyphenylacetic Acid metabolism, Animals, Brain metabolism, Brain Diseases chemically induced, Caudate Nucleus drug effects, Caudate Nucleus pathology, Chronic Disease, Corpus Striatum pathology, Dopamine metabolism, Ibotenic Acid pharmacology, Male, Putamen drug effects, Putamen pathology, Rats, Rats, Wistar, Tyrosine 3-Monooxygenase metabolism, Corpus Striatum metabolism, RNA, Messenger metabolism, Tyrosine 3-Monooxygenase genetics
- Abstract
Twenty weeks after ibotenic acid lesions of the striatum, the amount of tyrosine hydroxylase (TH) in this structure was markedly increased. This was accompanied by a 3-fold increase in TH mRNA levels in the ipsilateral subtantia nigra (SN). Striatal levels of dopamine (DA) and dihydroxyphenylacetic acid (DOPAC) were markedly reduced. In the nucleus accumbens, spared by the lesion, DA neurotransmission was also altered, as evidenced by a reduction of DA and DOPAC, but no increase in TH could be detected. TH mRNA levels were moderately enhanced in the ventral tegmental area (VTA). Thus, lesioning in the striatum induces TH gene activation in both SN and VTA neurones, not strictly related to DA function at the terminal level.
- Published
- 1994
- Full Text
- View/download PDF
163. Regional chemotherapy (with mitomycin C) and intra-operative hyperthermia for digestive cancers with peritoneal carcinomatosis.
- Author
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Gilly FN, Carry PY, Sayag AC, Brachet A, Panteix G, Salle B, Bienvenu J, Burgard G, Guibert B, and Banssillon V
- Subjects
- Adenocarcinoma drug therapy, Adenocarcinoma secondary, Adult, Aged, Analysis of Variance, Chemotherapy, Cancer, Regional Perfusion, Combined Modality Therapy, Digestive System Neoplasms drug therapy, Digestive System Neoplasms pathology, Female, Follow-Up Studies, Humans, Intraoperative Care, Male, Middle Aged, Mitomycin administration & dosage, Peritoneal Neoplasms drug therapy, Peritoneal Neoplasms secondary, Adenocarcinoma therapy, Digestive System Neoplasms therapy, Hyperthermia, Induced, Mitomycin therapeutic use, Peritoneal Neoplasms therapy
- Abstract
Intraperitoneal chemo-hyperthermia with mitomycin C was used to treat 28 patients with far advanced digestive adenocarcinoma and histologically confirmed peritoneal carcinomatosis. Surgical resection of the primary tumor was possible in 17 cases. After closure of the abdominal wall, intraperitoneal chemo-hyperthermia was performed for 90 to 120 minutes under general anesthesia and 32 degrees C hypothermia, through 3 intraperitoneal drains forming a closed circuit, using 10 mg/l of mitomycin C in 6 liters of peritoneal dialysate heated to an inflow temperature of 46-49 degrees C. No mortality occurred, and there were 2 post-operative complications, with transitory biological side effects. In 9 out of 10 patients with preoperative malignant ascites, the ascites cleared after treatment. One-year survival rate was 54.2%. These encouraging preliminary results show that intraperitoneal chemohyperthermia with mitomycin C is a safe and reliable treatment for peritoneal carcinomatosis in far advanced digestive cancers.
- Published
- 1994
164. Antibiotics and production of granulocyte-macrophage colony-stimulating factor by human bronchial epithelial cells in vitro. A comparison of cefodizime and ceftriaxone.
- Author
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Pacheco Y, Hosni R, Dagrosa EE, Gormand F, Guibert B, Chabannes B, Lagarde M, and Perrin-Fayolle M
- Subjects
- Aged, Bronchi drug effects, Cefotaxime pharmacology, Cells, Cultured, Enzyme-Linked Immunosorbent Assay, Epithelium drug effects, Epithelium metabolism, Female, Humans, Interleukin-8 biosynthesis, Male, Middle Aged, Tumor Necrosis Factor-alpha pharmacology, Bronchi metabolism, Cefotaxime analogs & derivatives, Ceftriaxone pharmacology, Granulocyte-Macrophage Colony-Stimulating Factor biosynthesis
- Abstract
Cultured human bronchial epithelial cells (HBEC) produce both granulocyte-macrophage colony-stimulating factor (GM-CSF) and interleukin 8 (IL-8). The influence of cefodizime (CAS 69739-16-8), a new broad spectrum cephalosporin with immunostimulatory effects, and ceftriaxone on the production of GM-CSF and IL-8 in HBEC primary cultures was investigated. HBEC were isolated from biopsy specimens obtained during fibreoptic bronchoscopy in 12 patients (most frequent diagnosis: chronic bronchitis). Confluent monolayers of HBEC cultured on collagen were incubated for 24 h in a medium without study drugs (spontaneous production) or containing cefodizime or ceftriaxone at the clinically relevant concentrations of 1, 10 and 100 mg/l, with or without tumor necrosis factor alpha (TNF alpha, 100 U/ml). GM-CSF and IL-8 were measured in supernatant by ELISA technique. TNF alpha alone led to a significant (p < 0.005) increase in both GM-CSF and IL-8 production. Cefodizime induced a significant (p < 0.05), dose-dependent increase in GM-CSF release. No additive effect of cefodizime with TNF alpha was observed. Cefodizime did not affect IL-8 production and ceftriaxone had no influence on cytokine production. This is the first report of a stimulatory effect of a beta-lactam antibiotic on cytokine production by epithelial cells. GM-CSF production by epithelial cells is an important immunological step for neutrophil and monocyte recruitment and cell priming during lung defence. Previous studies with cefodizime in immunodepressed subjects have shown activation of phagocytosis and phagocytosis-related functions in non-lung phagocytes. An indirect mechanism of action, similar to that indicated by our results, may have been responsible for these stimulatory effects.(ABSTRACT TRUNCATED AT 250 WORDS)
- Published
- 1994
165. Evidence for protein kinase C involvement in the short-term activation by prolactin of tyrosine hydroxylase in tuberoinfundibular dopaminergic neurons.
- Author
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Pasqualini C, Guibert B, Frain O, and Leviel V
- Subjects
- Animals, Dopamine pharmacology, Enzyme Activation, Female, Hypothalamus cytology, In Vitro Techniques, Median Eminence enzymology, Ovariectomy, Protein Kinase Inhibitors, Rats, Rats, Wistar, Time Factors, Tyrosine 3-Monooxygenase antagonists & inhibitors, Dopamine physiology, Hypothalamus metabolism, Neurons metabolism, Prolactin pharmacology, Protein Kinase C physiology, Tyrosine 3-Monooxygenase metabolism
- Abstract
The mechanism of the short-term activation by prolactin (PRL) of tyrosine hydroxylase (TH) in tuberoinfundibular dopaminergic neurons was examined in vitro on hypothalamic slices from ovariectomized rats. TH activity (determined by 3,4-dihydroxyphenylalanine accumulation in the median eminence after blockade of decarboxylase with NSD 1055) showed a dose-dependent increase within 2 h of incubation of the hypothalamic slices with PRL. To determine whether a phosphorylation process was involved in this increase in TH activity, we studied the sensitivity of the enzyme to dopamine (DA) feedback inhibition. In control median eminences, two kinetically different forms of TH coexisted, one exhibiting a Ki(DA) value of 29.92 +/- 0.49 microM, the other being approximately 15-fold more sensitive to DA inhibition with a Ki(DA) of 1.96 +/- 0.09 microM, likely corresponding to a phosphorylated and active form and to a nonphosphorylated and less active form, respectively. After PRL treatment, the TH form of low Ki(DA) remained unaffected, whereas the Ki(DA) of the purported active form of TH increased to 62.6 +/- 0.8 microM, suggesting an increase in the enzyme phosphorylation. This increase in the Ki(DA) of TH was selectively prevented by GF 109203X, a potent and selective inhibitor of protein kinase C, but not by a specific inhibitor of protein kinase A or calmodulin. Finally, this action of PRL could be mimicked by 12-O-tetradecanoylphorbol 13-acetate (a direct activator of protein kinase C). These results suggest that PRL, at the median eminence level, activates TH by increasing the enzyme phosphorylation and that this action may involve an activation of protein kinase C.
- Published
- 1994
- Full Text
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166. [Recurrent hemothorax due to pleural endometriosis].
- Author
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Bombaron P, Laënnec E, Guibert B, Neyra M, and Vincent M
- Subjects
- Adult, Biopsy, Combined Modality Therapy, Endometriosis diagnosis, Endometriosis therapy, Female, Gonadotropin-Releasing Hormone analogs & derivatives, Humans, Menstruation, Pleural Diseases diagnosis, Pleural Diseases therapy, Recurrence, Thoracoscopy, Treatment Failure, Endometriosis complications, Hemothorax etiology, Pleural Diseases complications
- Abstract
We report a case of a 31 year old woman with recurrent hemothorax at the beginning of mens. Pleural biopsy confirmed the diagnosis of pleural endometriosis. Medical treatment with a Gn-RH analogue failed to cure and we realised surgical pleurodesis.
- Published
- 1994
167. Short-term inhibitory effect of estradiol on tyrosine hydroxylase activity in tuberoinfundibular dopaminergic neurons in vitro.
- Author
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Pasqualini C, Guibert B, and Leviel V
- Subjects
- Animals, Catalysis, Dactinomycin pharmacology, Dopamine pharmacology, Ethers, Cyclic pharmacology, Female, Hypothalamus cytology, In Vitro Techniques, Median Eminence enzymology, Neurons cytology, Okadaic Acid, Phosphoprotein Phosphatases antagonists & inhibitors, Proteins antagonists & inhibitors, Rats, Rats, Wistar, Time Factors, Tyrosine 3-Monooxygenase antagonists & inhibitors, Estradiol pharmacology, Hypothalamus enzymology, Neurons enzymology, Tyrosine 3-Monooxygenase metabolism
- Abstract
The short-term inhibition by estradiol of tyrosine hydroxylase (TH) in tuberoinfundibular dopaminergic neurons was examined in vitro on hypothalamic slices from ovariectomized rats. TH activity (determined by L-3,4-dihydroxyphenylalanine accumulation in the median eminence after blockade of decarboxylase with NSD 1055) showed a 30-40% decrease within 1 h of incubation with estradiol. To determine whether a dephosphorylation process was involved in this decline in TH activity, we studied the sensitivity of the enzyme to dopamine (DA) feedback inhibition: In controls, we observed that two kinetically different forms of TH coexisted, with one exhibiting a Ki(DA) of 26.4 +/- 2 microM and the other being approximately 10-fold more sensitive to DA inhibition, with a Ki(DA) of 2.56 +/- 0.17 microM, likely corresponding to a phosphorylated and active form and to a nonphosphorylated and poorly active form, respectively. Conversely, after estradiol treatment all TH molecules exhibited the same Ki(DA) of 2.5 +/- 0.3 microM. This effect was stereospecific, because 17 alpha-estradiol could not promote it, whereas with 17 beta-estradiol, it could be observed at only 10(-11) M and after a short delay (30 min). Finally, this decrease in the Ki(DA) of the purported active form of TH could be prevented by okadaic acid (an inhibitor of protein phosphatases). These results suggest that estradiol can act directly on the mediobasal hypothalamus to trigger a rapid decline in TH activity and that this action may involve a decrease in TH phosphorylation.
- Published
- 1993
- Full Text
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168. Analysis of the human dopamine beta-hydroxylase promoter: transcriptional induction by cyclic AMP.
- Author
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Lamouroux A, Houhou L, Biguet NF, Serck-Hanssen G, Guibert B, Icard-Liepkalns C, and Mallet J
- Subjects
- Animals, Base Sequence, Cell Line, Transformed, Genes drug effects, Haplorhini, Humans, Molecular Sequence Data, Oligonucleotide Probes genetics, Transfection, Cyclic AMP pharmacology, Dopamine beta-Hydroxylase genetics, Promoter Regions, Genetic, Transcription, Genetic
- Abstract
We have analyzed some functional aspects of the promoter of the human dopamine beta-hydroxylase (DBH) gene. A fragment of 1,247 bp directly 5' to the transcriptional start was progressively shortened, placed in front of a reporter gene, and tested in a human neuroblastoma cell line expressing DBH (SK-N-SH-TFM) and in a monkey kidney cell line (CV-1). A remarkably short region (267 bp), directly upstream from the transcription start, was sufficient to confer activity and tissue-specific expression. Furthermore, the expression of the DBH gene was shown to be inducible by cyclic AMP in SK-N-SH-TFM cells. This effect was demonstrated to occur at the transcriptional level, as shown by run-on assays, and was due to the presence of a near-consensus cyclic AMP-responsive element located in the untranscribed 5' regulatory region of the gene.
- Published
- 1993
- Full Text
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169. [Decrease of pineal AMPc and TOH activity in the superior cervical ganglia after ablation of submaxillary glands in rats].
- Author
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Litovsky B, Boyer R, Pasqualini C, Guibert B, Alonso G, and Arancibia S
- Subjects
- Animals, Depression, Chemical, Male, Rats, Rats, Inbred Strains, Submandibular Gland surgery, Cyclic AMP analysis, Ganglia, Sympathetic enzymology, Pineal Gland chemistry, Tyrosine 3-Monooxygenase metabolism
- Abstract
In order to investigate a possible functional relationship between the submandibular salivary gland (SSG) and the central nervous system (CNS), we have extirpated the salivary organs from thirty male rats. Twenty days after ablation both the pineal glands and the cervical superior ganglions (CSG) were dissected, homogenized and frozen until AMPc and TOH were assayed respectively. We observed a significant decrease in pineal AMPc (53.9 +/- 6.2 vs 76.1 +/- 7.6% of maximum value; p less than 0.02) which seems to be linked with a significant drop in TOH activity measured at CSG level (1.5 +/- 0.6 vs 3.7 +/- 0.9 nmoles of DOPA/h/pair GCS; p less than 0.03). Our results suggest that both findings might be due to the lack of NGF normally reaching the CSG from SSG. This data reinforces the idea of a functional link between SSG and CNS via the pineal gland.
- Published
- 1992
170. Inhibitory actions of acute estradiol treatment on the activity and quantity of tyrosine hydroxylase in the median eminence of ovariectomized rats.
- Author
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Pasqualini C, Leviel V, Guibert B, Faucon-Biguet N, and Kerdelhué B
- Abstract
Abstract The effects of acute estradiol (E(2)) treatment on both the activity of tyrosine hydroxylase (TH) in the median eminence and the serum level of prolactin (PRL) were investigated. Twelve-day-ovariectomized rats were injected with 17beta-E(2) (25mug sc) at 1100 h and sacrificed hourly from 1200 to 2300 h. TH activity was quantified by measuring the amount of exogenous tyrosine converted to L-DOPA in vitro by aliquots of median eminence homogenates. Serum PRL levels were evaluated by radioimmunoassay. A biphasic response of TH activity to treatment was observed: an immediate decrease occurred-preceding and accompanying a rise in serum PRL-followed by an increase beyond control levels 2 h after the maximal release of PRL. The increase in TH activity could be prevented by the pretreatment of rats with a specific rat PRL antiserum, suggesting it was not due to E(2) per se but rather mediated by the E(2)-induced PRL elevation. To pin-point the process underlying the E(2)-induced decrease in TH activity, we evaluated the kinetic parameters of TH in the median eminence as well as its quantity (by Western blot analysis) in the median eminence and arcuate nucleus. Finally, we used a sensitive dot-blot assay to quantify specific TH messenger ribonucleic acid in the arcuate nucleus. The decrease in TH activity after E(2) treatment paralleled an immediate decrease in the affinity of TH for its pterin cofactor (6-MPH4), while V(max) remained unchanged. A decrease in the amount of TH protein in the arcuate nucleus and median eminence as well as in the TH messenger ribonucleic acid level in the arcuate nucleus was also observed, but the latency of these effects precluded a major involvement in the immediate decline of TH activity. Therefore, when observed separately from those of PRL, E(2) effects on TH in tuberoinfundibular dopaminergic neurons are clearly inhibitory consisting of a 'deactivation' of the enzyme together with a reduction of its synthesis.
- Published
- 1991
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171. Relationships between benzodiazepine receptors, impairment of GABAergic transmission and convulsant activity of beta-CCM: a PET study in the baboon Papio papio.
- Author
-
Chavoix C, Brouillet E, Kunimoto M, De la Sayette V, Khalili-Varasteh M, Hantraye P, Dodd RH, Guibert B, Prenant C, and Naquet R
- Subjects
- Animals, Brain diagnostic imaging, Brain metabolism, Carbolines metabolism, Flumazenil pharmacokinetics, Male, Papio, Receptors, GABA-A metabolism, Carbolines pharmacology, Convulsants pharmacology, Receptors, GABA-A physiology, Synaptic Transmission, Tomography, Emission-Computed, gamma-Aminobutyric Acid physiology
- Abstract
Central type benzodiazepine receptors were studied in vivo by positron emission tomography in brain areas of 2 different groups of the baboon Papio papio: non-photosensitive (group 1) and those with an allylglycine-induced decrease in GABA-mediated inhibition (group 2). Further, a naturally photosensitive Papio papio (+3 level of photosensitive response) was compared to both groups. Regional brain binding of the specific benzodiazepine receptor ligand, [11C]Ro 15-1788, was not significantly different between groups 1 and 2. In addition, the data from the naturally photosensitive Papio papio did not seem to differ markedly from groups 1 and 2 either. Pharmacological effects of increasing doses of beta-CCM (0.05-3 mg/kg i.v.) and regional benzodiazepine receptor occupancy by the drug were simultaneously studied using electroencephalographic activity recording and positron emission tomography. A positive correlation was observed between the degree of photosensitivity of the baboon and sensitivity to the action of beta-CCM, with increasing convulsant efficacy of beta-CCM in going from group 1 to the naturally photosensitive baboon, then to group 2. Dose-related displacement curves of [11C]Ro 15-1788 binding by beta-CCM revealed that reduction in brain GABA concentration did not modify the inhibitory potency of beta-CCM on [11C]Ro 15-1788 binding in cerebral cortex. This suggests a lack of detectable in vivo allosteric effects of GABA on beta-CCM binding during beta-CCM-induced seizures. Thus, a given dose of beta-CCM displayed increasing pharmacological potency in going from baboons with the lowest photosensitivity to those with the highest, whereas benzodiazepine receptor occupancy by beta-CCM was similar in the cerebral cortex of the different baboons. Conversely, a given level of convulsant activity of beta-CCM was related to a different benzodiazepine receptor occupancy by the drug, depending on the photosensitivity of Papio papio. A given dose of a drug may, thus, have a different pharmacological potency when occupying the same number of receptors, depending on the physiopathological state of the subject.
- Published
- 1991
- Full Text
- View/download PDF
172. [Pulmonary histoplasmosis due to Histoplasma capsulatum. A case].
- Author
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Mongeal E, Balduin MT, Voloch A, Souquet PJ, Pinet S, Piens MA, Guibert B, and Bernard JP
- Subjects
- Aged, Diagnosis, Differential, Female, Histoplasma, Humans, Histoplasmosis pathology, Lung Diseases, Fungal pathology
- Abstract
The authors report a case of benign multinodular pulmonary histoplasmosis, occurring in a 65 year old woman coming back from Guatemala. The disease presented with both fever and cough. The diagnosis was made on a lung biopsy (by thoracotomy) that showed granulomas with giant cells, lymphocytes and central necrosis, and histoplasma capsulatum yeasts on Gomori Grocott coloration. The authors recall the main radiological forms of the disease, and the difficulties of the diagnosis. When not disseminated, histoplasmosis usually has a good prognosis and does not require any treatment.
- Published
- 1991
173. Short- and long-term alterations of gene expression in limbic structures by repeated electroconvulsive-induced seizures.
- Author
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Leviel V, Fayada C, Guibert B, Chaminade M, Machek G, Mallet J, and Biguet NF
- Subjects
- Animals, Enkephalin, Methionine metabolism, Enkephalins genetics, Limbic System metabolism, Male, Protein Precursors genetics, RNA, Messenger metabolism, Rats, Rats, Inbred Strains, Tyrosine 3-Monooxygenase genetics, Tyrosine 3-Monooxygenase metabolism, Electroshock, Gene Expression Regulation, Limbic System physiology, Seizures genetics
- Abstract
Rats were submitted to a series of 10 daily electroconvulsive shocks (ECS). A first group of animals was killed 1 day after the last seizure and a second group 30 days later. Tyrosine hydroxylase (TH) activity was measured using an in vitro assay in the nucleus caudatus, anterior cortex, amygdala, substantia nigra, ventral tegmental area, and locus ceruleus. The mRNA corresponding to this enzyme (TH-mRNA) was evaluated using a cDNA probe at the cellular level in the ventral tegmental area, substantia nigra, and locus ceruleus. Met-enkephalin (MET)-immunoreactivity and the mRNA coding for the preproenkephalin (PPE-mRNA) were assayed in striatum and the central nucleus of the amygdala. The day after the last ECS an increase of TH activity was observed in the ventral tegmental area, locus ceruleus, and substantia nigra in parallel with a similar increase in the amygdala and striatum; in the anterior cortex TH activity remained unchanged. TH-mRNA was increased in the locus ceruleus, evidencing the presence in this structure of a genomic activation. The amounts of MET and PPE-mRNA were unaffected in the striatum but increased in the amygdala. Thirty days after the last ECS we observed a decrease of TH activity in the amygdala and of TH-mRNA amount in the ventral tegmental area. In the locus ceruleus TH-mRNA remained higher in treated animals than in controls whereas TH activity returned to control levels. These results demonstrate that a series of ECS induces an initial increase of the activity of mesoamygdaloid catecholaminergic neurons followed by a sustained decrease through alterations of TH gene expression which could mediate the clinical effect of the treatment.
- Published
- 1990
- Full Text
- View/download PDF
174. [Benign fibrous tumors of the pleura revealed by articular pathology. 2 cases].
- Author
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Souquet PJ, Mélinand F, Velay B, Voloch A, Guibert B, and Bernard JP
- Subjects
- Aged, Female, Fibroma diagnosis, Humans, Male, Middle Aged, Pleural Neoplasms diagnosis, Tomography, X-Ray Computed, Fibroma complications, Pleural Neoplasms complications, Rheumatic Diseases complications
- Published
- 1990
175. [Bronchogenic cysts and their atypical localizations. A case of pleuro-diaphragmatic cyst].
- Author
-
Letanche G, Boyer J, Guibert B, Maisonneuve M, Bernard JP, and Touraine R
- Subjects
- Adult, Diaphragm, Humans, Male, Mediastinal Cyst diagnosis, Mediastinal Cyst surgery, Mediastinal Neoplasms diagnosis, Mediastinal Neoplasms surgery, Pleura, Teratoma diagnosis, Teratoma surgery, Mediastinal Cyst congenital, Mediastinal Neoplasms congenital, Teratoma congenital
- Abstract
Bronchogenic cysts represent about 10 p. 100 of all surgical tumours of the mediastinum. They can never be diagnosed with absolute certainty prior to the operation, but when they arise in their typical sites, they can be suspected with a high probability. However, they can occur in very atypical sites, in which case the diagnosis remains very hypothetical until the operation. The authors report a case of a cyst which developed under the diaphragmatic pleura, in direct contact with the dome of the diaphragm and attached to the mediastinum by a fine vascular pedicle which inserted in the root of the triangular ligament.
- Published
- 1984
176. [Tracheal diverticuli: apropos of a case: malformation etiopathogenesis?].
- Author
-
Jegaden O, Boyer J, Guibert B, Devolfe C, and Morin A
- Subjects
- Diverticulum embryology, Diverticulum surgery, Humans, Male, Middle Aged, Trachea embryology, Tracheal Diseases embryology, Tracheal Diseases surgery, Diverticulum pathology, Trachea abnormalities, Tracheal Diseases pathology
- Abstract
A case of 3 contiguous diverticula of the right posterior wall of the upper trachea is reported. The earlier literature on this subject and the different classifications described are studied. Congenital genesis of the tracheal diverticula is suggested by their localisation and histologic bronchial elements, and by embryogenesis and anomalies of the trachea. They are presumed to correspond to a rudimentary, extra, apical bronchis.
- Published
- 1985
177. [Cytological diagnosis of prostatic cancer by transrectal aspiration biopsy (author's transl)].
- Author
-
Clavel E, Fontanière B, Guibert B, and Faucon M
- Subjects
- Biopsy, Needle, Cytodiagnosis methods, Humans, Male, Prostatic Neoplasms diagnosis, Rectum, Prostatic Neoplasms pathology
- Abstract
From the cytologic study of fifty transrectal needle aspirations of the prostate the authors try to establish the principles leading to the diagnosis of prostatic carcinoma. Correlation with clinical diagnosis shows that in positive cases, cytologic diagnosis is accurate. In the case of negative cytologic responses this negative response may be imputable: to the paucicellularity of the sample, unavoidable blind needle aspiration, an early necrosis of the cellular material, a false interpretation of minimal cellular and nuclear abnormalities. This method proves valuable for the clinician. In two cases out of three the cytological diagnosis confirms the clinical diagnosis.
- Published
- 1980
178. Benzodiazepine receptors studied in living primates by positron emission tomography: antagonist interactions.
- Author
-
Hantraye P, Brouillet E, Fukuda H, Chavoix C, Guibert B, Dodd RH, Prenant C, Crouzel M, Naquet R, and Mazière M
- Subjects
- Animals, Benzodiazepines antagonists & inhibitors, Benzodiazepinones pharmacology, Carbolines pharmacology, Cerebral Cortex diagnostic imaging, Cerebral Cortex metabolism, Flumazenil pharmacology, Male, Occipital Lobe metabolism, Papio, Temporal Lobe metabolism, Tomography, Emission-Computed, Anti-Anxiety Agents antagonists & inhibitors, Receptors, GABA-A drug effects
- Abstract
After labelling the brain benzodiazepine receptors of sub-human primates with [11C]RO15-1788, the interactions of different benzodiazepine receptor antagonist ligands were studied by positron emission tomography (PET). Various doses of either RO15-1788, RO15-3505 or propyl beta-carboline-3-carboxylate were injected intravenously 20 min after the radiotracer, and induced an immediate and specific dose-dependent displacement of the brain radioactivity. However, a comparison of the dose-receptor occupancy patterns of these three antagonists established from the displacement experiments revealed that only propyl beta-carboline-3-carboxylate displayed clear biphasic dose-receptor occupancy curves. This indicates that, in the living primate brain, there are two different benzodiazepine receptor subpopulations (which can be either different benzodiazepine receptor subtypes or distinct conformational states of a single receptor).
- Published
- 1988
- Full Text
- View/download PDF
179. [Perforation of the cervical esophagus and hypopharynx complicating surgery by an anterior approach to the cervical spine].
- Author
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Roche M, Gilly F, Carret JP, Guibert B, Braillon G, and Dejour H
- Subjects
- Adult, Esophageal Perforation diagnosis, Esophageal Perforation therapy, Female, Humans, Male, Middle Aged, Time Factors, Wounds, Penetrating diagnosis, Wounds, Penetrating etiology, Wounds, Penetrating therapy, Cervical Vertebrae surgery, Esophageal Perforation etiology, Fractures, Bone surgery, Hypopharynx injuries, Postoperative Complications
- Abstract
Difficult diagnostic and therapeutic problems are raised by perforations of the cervical oesophagus or hypopharynx in patients undergoing surgery to the cervical spine via an anterior approach. Based on their experience of three recent cases, the authors review the diagnostic approach, based on clinical examination and diatrizoate sodium oesophageal series, and propose conservative treatment consisting of surgical drainage with or without suture of the perforation and without removal of the osteosynthesis material, appropriate antibiotic therapy and hypercaloric enteral nutrition via nasogastric tube. The prevention of this complication is based on correct use of surgical retractors.
- Published
- 1989
180. [Cytological diagnosis of prostatic cancer by transrectal aspiration biopsy (author's transl)].
- Author
-
Clavel E, Fontanière B, Guibert B, and Faucon M
- Subjects
- Aged, Biopsy, Needle methods, Humans, Male, Middle Aged, Prostate cytology, Prostatic Hyperplasia pathology, Prostatic Neoplasms pathology
- Published
- 1979
181. [Benign metastatic ameloblastoma. A case report and review of the literature].
- Author
-
Freidel M, Le Bescond Y, Hyvernat P, Ollagnier C, Guibert B, and Rochet M
- Subjects
- Aged, Ameloblastoma diagnosis, Biopsy, Female, Humans, Lung pathology, Lung Neoplasms diagnosis, Lung Neoplasms pathology, Maxilla pathology, Maxillary Neoplasms diagnosis, Ameloblastoma pathology, Lung Neoplasms secondary, Maxillary Neoplasms pathology
- Abstract
A 78 year old woman with a history of maxillary ameloblastoma from age of 38 years was found on routine examination to have a pulmonary image of the balloon release type. The lesion was atypical with respect to its clinical tolerance and slow progression. Pathology of several nodules removed by surgical lung biopsy confirmed the benign nature and identity of the maxillary and pulmonary lesions. The diagnosis was therefore pulmonary metastases from a benign ameloblastoma. The age of the patient and slow course of the lesion, combined with the absence of any functional disorder, was the basis for the decision not to operate on the pulmonary lesion. The concept of benign metastatic ameloblastoma is analyzed and findings compared with data in the literature.
- Published
- 1987
182. [Study of specific binding sites of benzodiazepines using positron emission tomography in live baboons (Papio papio)].
- Author
-
Hantraye P, Brouillet E, Chavoix C, Guibert B, de la Sayette V, Naquet R, and Mazière M
- Subjects
- Animals, Binding Sites, Male, Papio, Receptors, GABA-A metabolism, Brain metabolism, Receptors, GABA-A analysis, Tomography, Emission-Computed
- Published
- 1987
183. Effects of naloxone on dopamine release in the nigrostriatal system.
- Author
-
Daudet F, Leviel V, Kerny C, Guibert B, and Barberis C
- Subjects
- Animals, Cats, Caudate Nucleus metabolism, Dextroamphetamine pharmacology, Electric Stimulation, Evoked Potentials drug effects, Neural Pathways drug effects, Neural Pathways metabolism, Substantia Nigra metabolism, Synaptic Transmission drug effects, Caudate Nucleus drug effects, Dopamine metabolism, Naloxone pharmacology, Substantia Nigra drug effects
- Abstract
Simultaneously with a systemic injection of naloxone (NAL), the effects of the nigral application of the d(+)-amphetamine (AMPH) or of right forepaw stimulation on the release of [3H]dopamine [( 3H]DA) in the two caudate nuclei (CN) and the two substantia nigrae (SN) were examined in halothane-anesthetized cats. These experiments were carried out using four push-pull cannulae implanted bilaterally in the CN and SN and continuously supplied with [3H]tyrosine [( 3H]Tyr), the metabolic precursor of dopamine. Nigral AMPH application (1 muM) produced a local increase of the [3H]DA in spite of the NAL injection (5 mg/kg) but the presence of this drug prevented the expected effect of AMPH in the three other structures. Furthermore, the effects of electrical forepaw stimulation (EPS) were abolished by injection of NAL. NAL alone had no effect on the spontaneous release of [3H]DA. It is concluded that antagonism between NAL and AMPH could be due: (1) to enkephalinergic control of dopamine regulated nigral efferents, (2) to an action on the thalamic structures responsible for the reciprocal control of the two nigrostriatal dopaminergic pathways.
- Published
- 1983
- Full Text
- View/download PDF
184. Central type benzodiazepine binding sites: a positron emission tomography study in the baboon's brain.
- Author
-
Hantraye P, Kaijima M, Prenant C, Guibert B, Sastre J, Crouzel M, Naquet R, Comar D, and Maziere M
- Subjects
- Animals, Benzodiazepinones metabolism, Binding, Competitive, Flumazenil, Kinetics, Molecular Conformation, Tomography, Emission-Computed, Benzodiazepines metabolism, Brain metabolism, Papio metabolism, Receptors, GABA-A metabolism
- Abstract
An in vivo characterization of specific central type benzodiazepine (BZD) binding sites, labelled with [11C]Ro 15-1788 was performed, using positron emission tomography. After i.v. injection of 10 mCi [11C]Ro 15-1788 (corresponding to 1 nmol/kg), sequential quantitative tomographic slices of the brain were obtained during 80 min. In some experiments various doses of different cold drugs (BZD agonist or antagonist) were injected i.v. subsequently in order to explore the specificity of the binding of the radioligand in brain structures. The main criteria usually utilized in vitro to demonstrate a specific binding to receptors, such as regional distribution, stereospecificity and saturability of the binding and pharmacological effect linked to the receptor's occupancy, were demonstrated in the brain of a living baboon.
- Published
- 1984
- Full Text
- View/download PDF
185. Benzodiazepine receptors studied in living primates by positron emission tomography: inverse agonist interactions.
- Author
-
Hantraye P, Chavoix C, Guibert B, Fukuda H, Brouillet E, Dodd RH, Prenant C, Crouzel M, Naquet R, and Mazière M
- Subjects
- Animals, Binding, Competitive drug effects, Carbolines pharmacology, Cerebral Cortex drug effects, Cerebral Cortex metabolism, Convulsants pharmacology, Dose-Response Relationship, Drug, Electroencephalography, Flumazenil metabolism, Flumazenil pharmacology, Male, Papio, Receptors, GABA-A drug effects, Tomography, Emission-Computed, Receptors, GABA-A metabolism
- Abstract
The convulsant actions of methyl 6,7-dimethoxy-4-ethyl-beta-carboline-3-carboxylate (DMCM) and of methyl beta-carboline-3-carboxylate (beta-CCM) were evaluated in the baboon (Papio papio). DMCM, 0.6-4 mg/kg, induced epileptic seizures with short latency. DMCM convulsive seizures could be blocked by i.v. administration of the benzodiazepine agonist diazepam (10 mg). Similarly, beta-CCM, 0.3-3 mg/kg i.v., provoked generalized seizures in the baboons. These seizures were also reversed by the administration of propyl beta-carboline-3-carboxylate (3 mg/kg) or of diazepam (5 mg/kg). Combining the results from Positron Emission Tomography and the EEG assessments, benzodiazepine receptor occupancy by beta-CCM and DMCM was directly correlated with their convulsant actions in the living baboon. beta-CCM exerted its convulsant action in the living baboon at 76 and 74% benzodiazepine receptor occupancy in, respectively, occipital and temporal cortices whereas DMCM displayed a similar convulsive activity when only 58 and 65% of these receptors in the above regions were occupied.
- Published
- 1987
- Full Text
- View/download PDF
186. [In vivo study of benzodiazepine receptors using positron emission tomography].
- Author
-
Maziere M, Prenant C, Sastre J, Crouzel M, Comar D, Cepeda C, Hantraye P, Kaijima M, Guibert B, and Naquet R
- Subjects
- Animals, Benzodiazepinones metabolism, Binding, Competitive, Chlordiazepoxide metabolism, Flumazenil, Kinetics, Lorazepam metabolism, Male, Papio, Receptors, GABA-A, Stereoisomerism, Brain metabolism, Flunitrazepam metabolism, Receptors, Cell Surface metabolism, Receptors, Neurotransmitter metabolism
- Abstract
The results obtained by positron-emission tomography in an "in vivo" study on the baboon using a benzodiazepine (flunitrazepam) labeled with carbon-11 are presented. The specificity of "in vivo" binding of Flunitrazepam-11C was demonstrated by competition with Lorazepam in the brain, but it was not possible to verify the criterium of stereospecificity "in vivo". The preliminary results of a study carried out under the same conditions on RO 15 1788 11C show the interest of using this labeled antagonist as an "in vivo" ligand for the specific binding sites of benzodiazepines in positron-emission tomography.
- Published
- 1983
187. Direct observation of dopamine compartmentation in striatal nerve terminal by 'in vivo' measurement of the specific activity of released dopamine.
- Author
-
Leviel V, Gobert A, and Guibert B
- Subjects
- Animals, Corpus Striatum drug effects, Male, Methyltyrosines pharmacology, Potassium pharmacology, Rats, Rats, Inbred Strains, Reserpine pharmacology, alpha-Methyltyrosine, Corpus Striatum metabolism, Dopamine metabolism, Nerve Endings metabolism
- Abstract
Rats were anesthetized with fluothane and implanted in the caudate nucleus with a push-pull cannula supplied with artificial CSF containing the tritiated precursor of dopamine (DA), [3H]tyrosine. Total DA and dihydroxyphenylacetic acid (DOPAC) were measured in successive 20 min fractions using high performance liquid chromatography and electrochemical detection. Radioisotopic counting of the peaks permitted the calculation of the specific activity of both DA and DOPAC released into the extracellular space. Local applications of potassium (8, 16 and 32 mM) induced a dose-dependent increase of the release of DA with a decrease of its specific activity as evidence of the involvement of a stored DA pool. Base release of DOPAC was increased by repeating potassium applications with a temporary decrease during the applications. Superfusion with alpha-methyl-p-tyrosine produced a decrease of both the [3H]DA and total DA with a simultaneous decrease of its specific activity. This decrease was considered to be an indicator of the involvement by synthesis inhibition of the stored amine, but the simultaneous decrease of the specific activity of DOPAC suggests that this release was intraterminal. These results constitute the first direct observation that DA terminals act with two separate pools (stored and releasable) and suggest that the stored amine is preferentially released intraterminally. Systemic injection of reserpine induced a decrease of the release of DA and DOPAC without alteration of DA-specific activity when the specific activity of DOPAC was lowered. From these results it is concluded that the releasable compartment of the amine is located, in part, in vesicles different in nature from the vesicles containing the stored amine.(ABSTRACT TRUNCATED AT 250 WORDS)
- Published
- 1989
- Full Text
- View/download PDF
188. [Pulmonary metastasis of an ameloblastoma].
- Author
-
Hyvernat P, Ollagnier C, Freidel M, Guibert B, and Rochet M
- Subjects
- Aged, Ameloblastoma diagnostic imaging, Ameloblastoma pathology, Female, Humans, Lung Neoplasms diagnostic imaging, Lung Neoplasms pathology, Radiography, Ameloblastoma secondary, Lung Neoplasms secondary, Maxillary Neoplasms
- Abstract
We report the observation of a 78 year old patient who had a plexiform ameloblastoma since the age of 38. A systematic pulmonary radiographic examination revealed multiple dense nodules like "cannon ball secondaries". However the histology of these pulmonary nodules, obtained by open lung biopsy, was identical with the primary tumour and showed no evidence of malignancy. The dispersion to the lungs was probably explained by inhalation of tumour cells, itself favoured by 8 surgical curettages. The progress of these pulmonary lesions was as slow as the primary tumour. No therapeutic trial was attempted on the grounds of age, perfect clinical tolerance and the absence of any known therapeutic protocol which would be active.
- Published
- 1985
189. Sequence of two mRNAs encoding active rat tryptophan hydroxylase.
- Author
-
Darmon MC, Guibert B, Leviel V, Ehret M, Maitre M, and Mallet J
- Subjects
- Amino Acid Sequence, Animals, Base Sequence, Cloning, Molecular, Codon, DNA genetics, DNA, Recombinant, Molecular Sequence Data, Molecular Weight, Nucleic Acid Hybridization, Pineal Gland analysis, Protein Biosynthesis, Rabbits, Rats, RNA, Messenger genetics, Tryptophan Hydroxylase genetics
- Abstract
Two full-length cDNA clones that encode functional rat tryptophan hydroxylase (EC 1.14.16.4), the key enzyme in serotonin synthesis, have been isolated from a rat pineal gland library. These two clones correspond to the 1.8- and 4-kilobase mRNA species, respectively. They contain the same coding sequence corresponding to a 51,010-dalton protein and differ in the length of their 3' untranslated regions.
- Published
- 1988
- Full Text
- View/download PDF
190. [11C-Ro15-1788 and 11C-flunitrazepam, two coordinates for the study by positron emission tomography of benzodiazepine binding sites].
- Author
-
Mazière M, Prenant C, Sastre J, Crouzel M, Comar D, Hantraye P, Kaïsima M, Guibert B, and Naquet R
- Subjects
- Animals, Benzodiazepines antagonists & inhibitors, Binding, Competitive, Brain metabolism, Flumazenil, Kinetics, Papio, Receptors, GABA-A, Tomography, Emission-Computed methods, Anti-Anxiety Agents metabolism, Benzodiazepines metabolism, Benzodiazepinones metabolism, Flunitrazepam metabolism, Receptors, Cell Surface metabolism
- Abstract
In vivo binding of a benzodiazepine (flunitrazepam-C11) and a benzodiazepine antagonist (Ro 15-1788-C11) were studied with positron emission tomography. Advantages and disadvantages of each drug for studying specific in vivo binding sites are presented. The results obtained indicate that Ro 15-1788-C11 is a better in vivo radiocoordinat than flunitrazepam-C11.
- Published
- 1983
191. [Carcinoid tumors of the thymus. 2 cases].
- Author
-
Chambon M, Maisonneuve M, and Guibert B
- Subjects
- Female, Humans, Male, Middle Aged, Carcinoid Tumor diagnosis, Thymus Neoplasms diagnosis
- Published
- 1987
192. Changes in tuberoinfundibular dopaminergic neuron activity during the rat estrous cycle in relation to the prolactin surge: alteration by a mammary carcinogen.
- Author
-
Pasqualini C, Bojda F, Gaudoux F, Guibert B, Leviel V, Teissier E, Rips R, and Kerdelhue B
- Subjects
- 3,4-Dihydroxyphenylacetic Acid metabolism, Animals, Female, Median Eminence metabolism, Rats, Rats, Inbred Strains, Tyrosine 3-Monooxygenase metabolism, 9,10-Dimethyl-1,2-benzanthracene pharmacology, Arcuate Nucleus of Hypothalamus metabolism, Dopamine metabolism, Estrus metabolism, Hypothalamus metabolism, Neurons metabolism, Prolactin blood, Tuber Cinereum metabolism
- Abstract
An attempt was made to correlate the physiological or the dimethylbenz(a)anthracene (DMBA)-enhanced serum prolactin (PRL) surge, which occurs in the afternoon of proestrus in female Sprague-Dawley (SD) rats, with physiological or pathological changes in two biochemical estimates of the tuberoinfundibular dopaminergic (TIDA) neuron activity. Dopamine (DA) and dihydroxyphenylacetic acid (DOPAC) concentrations as well as tyrosine hydroxylase (TH) activity were measured in the median eminence (ME) of control or DMBA-pretreated SD rats throughout the estrous cycle in relation to PRL secretion. In both groups of females, while the DA content was fairly constant, the DOPAC content and TH activity in the ME fluctuated markedly throughout the estrous cycle. Thus, in control animals, the DOPAC content, DOPAC/DA ratio and TH activity which were stable on the days of diestrus and morning of proestrus were markedly decreased at noon and early afternoon when serum PRL levels began to rise. Later in the afternoon of proestrus, when serum PRL levels were maximal, there was a marked but transient increase in the DOPAC content and DOPAC/DA ratio as well as a brief surge in TH activity. In the evening of the same day, when serum PRL returned to basal levels, the DOPAC content, DOPAC/DA ratio and TH activity were low. Finally on estrus morning, the DOPAC content, DOPAC/DA ratio and TH activity increased again to reach the diestrus levels. In DMBA-pretreated females, similar fluctuations in TIDA neuronal activity occurred during the estrous cycle, but the dynamics of these changes was altered: the DOPAC/DA ratio and TH activity first showed a marked increase in the morning of proestrus day, before decreasing dramatically.(ABSTRACT TRUNCATED AT 250 WORDS)
- Published
- 1988
- Full Text
- View/download PDF
193. A single RNA species injected in Xenopus oocyte directs the synthesis of active tyrosine hydroxylase.
- Author
-
Horellou P, Guibert B, Leviel V, and Mallet J
- Subjects
- Animals, Cloning, Molecular, DNA, In Vitro Techniques, Promoter Regions, Genetic, Protein Biosynthesis, Transcription, Genetic, Tyrosine 3-Monooxygenase genetics, Xenopus laevis, Oocytes enzymology, RNA physiology, Tyrosine 3-Monooxygenase biosynthesis
- Abstract
Tyrosine hydroxylase, the rate limiting enzyme in the biosynthesis of catecholamine, is a tetramer composed of four subunits of the same molecular mass. A full length cDNA clone encoding tyrosine hydroxylase has been inserted into the SP6 expression system. Translation of the corresponding RNA in Xenopus oocyte results in enzymatic activity, demonstrating that a single gene contains all the necessary genetic information to code for a functional enzyme. The potential of this system in the analysis of posttranslational tyrosine hydroxylase modifications is discussed.
- Published
- 1986
- Full Text
- View/download PDF
194. [Direct osteosynthesis of trochanteric fractures].
- Author
-
Chatin R, Colas M, Guibert B, Lagoutte J, and Setley L
- Subjects
- Age Factors, Aged, Humans, Prognosis, Femoral Fractures surgery, Fracture Fixation, Intramedullary
- Published
- 1972
195. [1st results of the use of Soludactone in the treatment of certain forms of cerebral edema].
- Author
-
Ravon R, Imbert D, Guibert B, Fischer G, and Mansuy L
- Subjects
- Adolescent, Adult, Aged, Aldosterone urine, Brain Edema complications, Female, Humans, Hyperaldosteronism drug therapy, Hyperaldosteronism etiology, Male, Middle Aged, Brain Edema drug therapy, Spironolactone therapeutic use
- Published
- 1970
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