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1.
Neuropathology ; 21(3): 241-4, 2001 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-11666023

RESUMO

Oculomotor paralysis of a patient with leukemia was revealed at autopsy to be caused by a hemorrhage in the oculomotor nerve. In a 63-year-old woman with pre-B-cell acute lymphatic leukemia, leukemic invasions occurred in her spinal cord and right oculomotor nerve during a hematological remission state. The oculomotor palsy was aggravated to complete paralysis during a leukemic relapse, which lasted until her death. An autopsy revealed a hemorrhage along with leukemic cells in the right oculomotor nerve at the segment in the upper orbital fissure. Although hemorrhagic oculomotor paralysis is a very rare complication, reports of its occurrence will likely increase with improved survival times of leukemia patients due to advances in chemotherapy.


Assuntos
Hemorragia/etiologia , Infiltração Leucêmica/complicações , Doenças do Nervo Oculomotor/etiologia , Nervo Oculomotor/patologia , Leucemia-Linfoma Linfoblástico de Células Precursoras/complicações , Medula Espinal/patologia , Doença Aguda , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Linfócitos B/metabolismo , Linfócitos B/patologia , Vértebras Cervicais , Feminino , Antígenos HLA/metabolismo , Hemorragia/patologia , Hemorragia/fisiopatologia , Humanos , Imuno-Histoquímica , Infiltração Leucêmica/patologia , Infiltração Leucêmica/fisiopatologia , Pessoa de Meia-Idade , Regressão Neoplásica Espontânea , Nervo Oculomotor/irrigação sanguínea , Nervo Oculomotor/fisiopatologia , Doenças do Nervo Oculomotor/patologia , Doenças do Nervo Oculomotor/fisiopatologia , Leucemia-Linfoma Linfoblástico de Células Precursoras/patologia , Leucemia-Linfoma Linfoblástico de Células Precursoras/fisiopatologia , Recidiva , Medula Espinal/irrigação sanguínea , Medula Espinal/fisiopatologia , Resultado do Tratamento
2.
Psychoneuroendocrinology ; 25(3): 277-87, 2000 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-10737698

RESUMO

In order to investigate the possibility that i.p. injection of pentobarbital sodium (PB, 32 mg/kg bw) potentiates the GnRH pulse generator activity, effects of i.v. infusions of an opiate receptor antagonist naloxone (NAL, 2 mg/h) on the pulsatile LH secretion were compared in saline (SAL)- and PB-injected rats in proestrus and diestrus 1. In SAL-injected rats in proestrus, NAL infusions significantly increased both the frequency and amplitude of LH pulses, and also the overall mean LH concentration. In PB-injected rats in proestrus, all the parameters of the pulsatile LH secretion were similar to those in SAL-injected rats in proestrus. The NAL infusion in PB-injected rats caused an increase in the frequency, but it was similar to that in SAL-injected rats. But, increases in the amplitude and the overall mean LH observed during NAL infusions in PB-injected rats were greater than in SAL-injected rats. In SAL-injected rats in diestrus 1, NAL infusions increased all the parameters, as in rats in proestrus. In PB-injected rats in diestrus 1, LH secretion was severely suppressed. NAL infusions recovered the pulsatile LH secretion, but the frequency and the overall mean LH of the secretion were smaller than those obtained during NAL infusions in SAL-injected rats. In addition, characteristic increases in the MUA (volleys), which occur in association with the initiation of an LH pulse and thus are considered to represent an increased activity of the GnRH pulse generator, appeared more frequently during NAL infusions in PB-injected rats in proestrus than in SAL-injected rats. These results suggest that the GnRH pulse generator in rats in proestrus, but not in rats in diestrus 1, is refractory to PB and further is potentiated by PB in the response to NAL. Together with the fact that this dosage of PB blocks the surge of LH secretion in rats in proestrus, the concept of the existence of separate neuronal mechanisms responsible for the surge and pulsatile secretion of LH are supported.


Assuntos
Relógios Biológicos/efeitos dos fármacos , Hormônio Liberador de Gonadotropina/biossíntese , Neurônios/efeitos dos fármacos , Pentobarbital/farmacologia , Proestro/efeitos dos fármacos , Potenciais de Ação/efeitos dos fármacos , Animais , Relógios Biológicos/fisiologia , Diestro/efeitos dos fármacos , Diestro/fisiologia , Eletrodos Implantados , Feminino , Hipotálamo/efeitos dos fármacos , Hipotálamo/metabolismo , Infusões Intravenosas , Hormônio Luteinizante/sangue , Hormônio Luteinizante/metabolismo , Naloxona/administração & dosagem , Naloxona/farmacologia , Antagonistas de Entorpecentes/farmacologia , Neurônios/citologia , Neurônios/metabolismo , Periodicidade , Proestro/fisiologia , Ratos , Ratos Wistar
3.
Acta Neuropathol ; 99(3): 327-30, 2000 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-10663978

RESUMO

The Ser149Arg mutation of peripheral myelin protein 22 (PMP22) was found in a 19-year-old woman with a sporadic case of Dejerine-Sottas disease. The patient showed delayed motor development. She walked for the first time with support at the age of 2 years. Scoliosis developed at age 4 years. Her walking ability was best at age 11. Thereafter, she showed progressive muscle weakness and sensory disturbances in the distal extremities. At the age of 18 years, the use of a wheelchair became necessary. Motor and sensory nerve conduction studies showed absent motor and sensory responses on electrical stimulation of the limb nerves. A sural nerve biopsy specimen showed marked decreases in the numbers of both large and small myelinated fibers, abundant onion-bulb formation, and hypomyelination. Electron microscopic observation revealed the presence of demyelinated axons and myelin sheaths disproportionately thin relative to axon diameter. That this was a de novo mutation was established by parentage testing and PMP22 gene analysis of the parents. The mutation seems to be novel and dominant.


Assuntos
Neuropatia Hereditária Motora e Sensorial/genética , Neuropatia Hereditária Motora e Sensorial/fisiopatologia , Proteínas da Mielina/genética , Nervos Periféricos/patologia , Nervos Periféricos/fisiopatologia , Adulto , Biópsia , Feminino , Neuropatia Hereditária Motora e Sensorial/patologia , Humanos , Microscopia Eletrônica , Nervos Periféricos/ultraestrutura , Nervo Sural/patologia , Nervo Sural/fisiopatologia , Nervo Sural/ultraestrutura
4.
Artigo em Inglês | MEDLINE | ID: mdl-11464955

RESUMO

BACKGROUND: Abnormalities of hyaluronic acid (HA) of skin have been reported in patients with amyotrophic lateral sclerosis (ALS). However, little is known concerning the changes of serum HA in ALS. The purpose of this study was to investigate skin HA content and serum HA levels in ALS patients. METHODS: We measured skin HA content and serum HA levels in patients with ALS, and compared the results with those of control subjects. RESULTS: Skin HA content in ALS patients was significantly higher than in diseased control subjects and control subjects without neurological disorders, and increased significantly, the longer the duration of illness. Serum HA concentrations in patients with ALS were significantly higher than in diseased control subjects and in healthy control subjects, and were positively and significantly associated with duration of illness. There was an appreciable positive correlation between serum HA concentrations and skin HA content in ALS patients. CONCLUSION: These data suggest that a metabolic alteration of HA may take place in ALS and increased levels of serum HA may reflect an increased content of skin HA in ALS.


Assuntos
Esclerose Lateral Amiotrófica/sangue , Ácido Hialurônico/análise , Ácido Hialurônico/sangue , Pele/química , Adulto , Idoso , Esclerose Lateral Amiotrófica/patologia , Biópsia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Pele/patologia
5.
Acta Neurol Scand ; 100(6): 377-84, 1999 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-10589797

RESUMO

OBJECTIVES: Collagen abnormalities of skin have been reported in patients with amyotrophic lateral sclerosis (ALS). However, little is known concerning the aminoterminal propeptide of type III procollagen (PIIIP) and type III collagen in ALS. The aim of this study is to measure PIIIP, a precursor form of type III collagen, in skin and serum of ALS. MATERIAL AND METHODS: We studied PIIIP immunoreactivity of skin and measured serum levels of PIIIP in ALS patients, and the results were compared with those of control subjects. RESULTS: Collagen bundles in the dermis of ALS were immunohistochemically strongly positive for PIIIP as compared with those of controls. The optical density of PIIIP immunostaining reactivity in ALS patients was significantly higher than in controls, and was significantly increased with duration of illness. Serum PIIIP levels in patients with ALS were significantly increased as compared with those in diseased control subjects and those in healthy control ones, and were positively and significantly associated with duration of illness. There was an appreciable positive correlation between concentrations of serum PIIIP and the density of PIIIP immunoreactivity of skin in ALS patients. CONCLUSION: These data suggest that a metabolic alteration of PIIIP may take place in the skin of ALS and the increased levels of serum PIIIP may reflect the increased PIIIP immunoreactivity of skin in ALS.


Assuntos
Esclerose Lateral Amiotrófica/complicações , Esclerose Lateral Amiotrófica/metabolismo , Pró-Colágeno/metabolismo , Pele/patologia , Atividades Cotidianas , Adulto , Idoso , Esclerose Lateral Amiotrófica/sangue , Esclerose Lateral Amiotrófica/patologia , Biópsia , Estudos de Casos e Controles , Colágeno/metabolismo , Feminino , Humanos , Imuno-Histoquímica , Masculino , Pró-Colágeno/sangue , Índice de Gravidade de Doença , Pele/metabolismo
6.
Muscle Nerve ; 22(9): 1271-4, 1999 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-10454725

RESUMO

Length of (CTG)n triplet repeats in myotonic dystrophy protein kinase gene (DMPK) was estimated in tumors, normal tissues of the same organs, muscles, and leukocytes from three myotonic dystrophy (DM) patients and a non-DM patient. Using cDNA 25 as a probe, a Southern blot analysis of EcoRI- and BglI-digested DNA from these tissues demonstrated the longest expansion of the repeats in the tumors of DM patients. In all tissues from a non-DM patient, the repeat length was confirmed to be stable by PCR analysis. Our data suggest that expanded (CTG)n repeat in tumor tissues may have increased the instability. This study emphasizes the importance of a long-term prospective study on the incidence of tumors in DM to clarify the pathological interrelation between the two entities.


Assuntos
Adenocarcinoma/genética , Neoplasias do Colo/genética , Insulinoma/genética , Distrofia Miotônica/complicações , Neoplasias Pancreáticas/genética , Proteínas Serina-Treonina Quinases/genética , Sequências Repetitivas de Ácido Nucleico , Neoplasias Gástricas/genética , Adenocarcinoma/complicações , Adenocarcinoma/enzimologia , Neoplasias do Colo/complicações , Neoplasias do Colo/enzimologia , DNA/química , DNA/metabolismo , Desoxirribonuclease EcoRI/metabolismo , Eletroforese em Gel de Campo Pulsado , Humanos , Insulinoma/complicações , Insulinoma/enzimologia , Leucócitos/enzimologia , Masculino , Pessoa de Meia-Idade , Músculo Esquelético/enzimologia , Miotonina Proteína Quinase , Neoplasias Pancreáticas/complicações , Neoplasias Pancreáticas/enzimologia , Neoplasias Gástricas/complicações , Neoplasias Gástricas/enzimologia
7.
Acta Neurol Scand ; 100(2): 111-6, 1999 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-10442453

RESUMO

OBJECTIVES: Type IV collagen (IV-C) abnormalities of skin and serum have been reported in patients with amyotrophic lateral sclerosis (ALS). However, there has been no study of urinary IV-C in ALS. The present study investigates urinary IV-C and the relation to its skin content in patients with ALS. MATERIAL AND METHODS: We studied IV-C immunoreactivity of skin and measured urinary levels of IV-C in ALS patients and controls. RESULTS: The basement membrane as well as blood vessels of skin in ALS patients was weakly positive for IV-C as compared with those of controls. Immunostaining became even weaker as ALS progressed. The urinary level of IV-C in ALS patients was significantly decreased as compared to diseased controls (P<0.001) and healthy controls (P<0.001), and was negatively and significantly associated with duration of symptoms (r=-0.85, P<0.001). There was an appreciable positive correlation between urinary IV-C levels and the density for IV-C immunoreactivity in ALS patients (r=0.84, P<0.01). CONCLUSION: These data suggest that a metabolic alteration of IV-C may occur in ALS patients and decreased levels of urinary IV-C may be related to the decreased IV-C immunoreactivity of skin in ALS.


Assuntos
Esclerose Lateral Amiotrófica/diagnóstico , Colágeno/urina , Idoso , Esclerose Lateral Amiotrófica/patologia , Esclerose Lateral Amiotrófica/urina , Biópsia , Feminino , Humanos , Técnicas Imunoenzimáticas , Masculino , Pessoa de Meia-Idade , Exame Neurológico , Valores de Referência , Pele/patologia
8.
Intern Med ; 38(6): 504-6, 1999 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-10411358

RESUMO

We describe a 51-year-old man with myotonic dystrophy (MyD) associated with insulinoma. In addition to the typical symptoms of MyD, he showed hypoglycemic attacks after meals. The radiological examination and selective blood sampling revealed an insulinoma in the head of the pancreas. The tumor was resected and histopathologically diagnosed as an insulinoma. In Southern blot analysis, CTG repeat of the myotonin protein kinase gene in the insulinoma showed the longest expansion, followed by normal tissue of the pancreas, muscle and white blood cells. Therefore, microsatellite instability was the most prominent in the tumor cells.


Assuntos
Insulinoma/complicações , Distrofia Miotônica/etiologia , Neoplasias Pancreáticas/complicações , Proteínas Serina-Treonina Quinases , Biomarcadores Tumorais/análise , Southern Blotting , Colangiopancreatografia Retrógrada Endoscópica , DNA de Neoplasias/análise , Humanos , Insulinoma/sangue , Insulinoma/diagnóstico , Insulinoma/cirurgia , Masculino , Pessoa de Meia-Idade , Distrofia Miotônica/sangue , Distrofia Miotônica/diagnóstico , Miotonina Proteína Quinase , Neoplasias Pancreáticas/sangue , Neoplasias Pancreáticas/diagnóstico , Neoplasias Pancreáticas/cirurgia , Proteínas Quinases/genética , Tomografia Computadorizada por Raios X , Expansão das Repetições de Trinucleotídeos
10.
Endocr J ; 45(4): 575-80, 1998 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-9881909

RESUMO

To determine the effect of nicotine on LH and PRL secretion, nicotine bitartrate (nicotine) dissolved in saline was administered at 1400 h, just before the critical period for the preovulatory surge of LH and PRL secretion, either intracerebroventricularly (icv) or intravenously (iv) in female rats in proestrus. Nicotine neither at a dose of 5 microg nor at a dose of 10 microg injected icv at 1400 h caused significant changes in the surge of LH and PRL secretion. When nicotine was given iv at a dose of 100 microg, a significant decrease in LH and PRL concentrations occurred immediately, lasting for 2 h. After 1700 h, LH and PRL concentrations as high as that observed after 1700 h in saline-injected control rats were recovered, just as if nicotine caused a transient deficit of the surge secretion of these hormones. The results indicate that nicotine does not inhibit the preovulatory surge of LH and PRL secretion by acting at the hypothalamic level accessible via the third ventricle, but inhibits it by acting at certain other site(s).


Assuntos
Fase Folicular/metabolismo , Hormônio Luteinizante/metabolismo , Nicotina/farmacologia , Prolactina/metabolismo , Animais , Feminino , Fase Folicular/efeitos dos fármacos , Injeções Intraventriculares , Nicotina/administração & dosagem , Fluxo Pulsátil , Ratos , Ratos Wistar
11.
Neuroreport ; 8(3): 771-4, 1997 Feb 10.
Artigo em Inglês | MEDLINE | ID: mdl-9106764

RESUMO

The effect of bicuculline (BIC) on Fos expression in lutenizing hormone-releasing hormone (LHRH) neurons was examined by immunocytochemistry. Proestrous rats were infused with saline (SAL 1400, n = 4) or BIC (BIC 1400, n = 5) for 3 h (10.00-13.00 h) and were killed at 1400 h. Three control rats (SAL 1700), which received saline infusion, were killed at 1700 h. In both the BIC 1400 group and the SAL 1700 group, many LHRH neurons in the preoptic area expressed Fos, but those in the SAL 1400 group did not. The distribution and proportion of LHRH neurons expressing Fos in the BIC 1400 group were identical to those in the SAL 1700 group. We conclude that GABAergic neurons play a critical role in inducing LH surge by controlling LHRH neuronal activity.


Assuntos
Bicuculina/análogos & derivados , Hormônio Liberador de Gonadotropina/metabolismo , Neurônios/fisiologia , Área Pré-Óptica/fisiologia , Proteínas Proto-Oncogênicas c-fos/biossíntese , Análise de Variância , Animais , Bicuculina/administração & dosagem , Bicuculina/farmacologia , Feminino , Infusões Intra-Arteriais , Cinética , Hormônio Luteinizante/sangue , Hormônio Luteinizante/metabolismo , Neurônios/efeitos dos fármacos , Área Pré-Óptica/efeitos dos fármacos , Proestro , Ratos , Ratos Wistar , Valores de Referência , Fatores de Tempo , Ácido gama-Aminobutírico/metabolismo
12.
J Neuroendocrinol ; 9(2): 87-92, 1997 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-9041360

RESUMO

Because Fos is thought to be induced in neurons that are activated, we examined whether luteinizing hormone-releasing hormone (LHRH) neurons expressed Fos protein when they were stimulated by an opioid receptor antagonist naloxone (NAL), expecting to identify LHRH neurons which are regulated by opioid neurons directly or indirectly. Further, we examined whether an ovulation-blocking dosage of pentobarbital sodium (PB) would affect the NAL-induced Fos expression. Female rats were infused with naloxone (5 mg/kg/h) for 90 min (10.00-11.30) in the morning of proestrus, during which infusion blood sampling was done, and were killed by i.v. injection with an overdose of PB at 11.30-12.00. Dual immunoperoxidase/immunofluorescence staining for both Fos and LHRH revealed that some LHRH immunoreactive (ir) neurons in the forebrain expressed Fos-ir, associated with an increase in serum LH concentrations, but little co-localization was found in rats in proestrus which were infused with saline as the control. The proportion of LHRH-ir neurons which expressed Fos-ir was about 35-62% in the caudal part of the forebrain including the mediobasal hypothalamus, and this was larger than that (10%) in the rostral part of the forebrain including the preoptic area. PB injection (32 mg/kg bw, i.p.) 15 min prior to the beginning of NAL infusion significantly enhanced the increase in LH secretion due to NAL, and also enhanced Fos-ir expression in LHRH-ir neurons. Together with the well-established fact that PB blocks the LHRH surge generator and our previous findings that NAL stimulates the LHRH pulse generator even in the PB-blocked proestrous rat, these results strongly suggest that the LHRH pulse generator exists in the mediobasal hypothalamus which contains LHRH neurons that are responsive to NAL and express Fos protein.


Assuntos
Genes fos , Hormônio Liberador de Gonadotropina/metabolismo , Hipotálamo Médio/metabolismo , Naloxona/farmacologia , Pentobarbital/farmacologia , Proestro/fisiologia , Animais , Feminino , Imunofluorescência , Expressão Gênica/efeitos dos fármacos , Hormônio Liberador de Gonadotropina/antagonistas & inibidores , Hipotálamo Médio/citologia , Hipotálamo Médio/efeitos dos fármacos , Técnicas Imunoenzimáticas , Hormônio Luteinizante/metabolismo , Antagonistas de Entorpecentes/farmacologia , Neurônios/efeitos dos fármacos , Neurônios/metabolismo , Ratos , Ratos Wistar
13.
Thorac Cardiovasc Surg ; 44(5): 264-5, 1996 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-8948557

RESUMO

We performed a sleeve lobectomy on a patient with squamous-cell carcinoma of the lung who had poor pulmonary function and could not move his extremities or trunk, due to a muscular dystrophy. Lung cancer in a highly disabled patient can be resected even with a bronchoplastic procedure.


Assuntos
Carcinoma de Células Escamosas/cirurgia , Neoplasias Pulmonares/cirurgia , Distrofias Musculares/complicações , Pneumonectomia/métodos , Biópsia , Carcinoma de Células Escamosas/complicações , Carcinoma de Células Escamosas/patologia , Avaliação da Deficiência , Humanos , Neoplasias Pulmonares/complicações , Neoplasias Pulmonares/patologia , Masculino , Pessoa de Meia-Idade , Distrofias Musculares/patologia , Distrofias Musculares/reabilitação
14.
Endocrinology ; 137(8): 3544-50, 1996 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-8754785

RESUMO

Ipriflavone (7-isopropoxyisoflavone) is an effective antiresorptive agent used to treat osteoporosis. However, the mechanism of its action on osteoclasts and their precursor cells is not well understood. To determine whether the mechanism involves direct effects on osteoclasts or their precursors, we examined the effects of ipriflavone on cytosolic free calcium ([Ca2+]i) in osteoclasts and their precursors and measured specific binding of 3H-labeled ipriflavone. Highly purified chicken osteoclast precursors, which spontaneously differentiate into multinucleated osteoclasts in 3-6 days, were loaded with fura-2, and the subcellular [Ca2+]i distribution was monitored by videoimaging. Ipriflavone induced a rapid increase in [Ca2+]i followed by a sustained elevation [EC50 = 5 x 10(-7) M, 263 +/- 74 nM (SE) (n = 8) above basal levels, by 10(-6) M ipriflavone, sustained phase]. The responses were the same in differentiated chicken osteoclasts and isolated rabbit osteoclasts. An influx of extracellular Ca2+ is likely to be responsible for the ipriflavone-induced change in [Ca2+]i because the response was abolished by 0.5 mM LaCl3, or by Ca-free medium containing EGTA. Moreover, high [Ca2+]i levels were detected adjacent to the cell membrane after ipriflavone addition. Ipriflavone induced Ca influx mainly through dihydropyridine-insensitive Ca2+ channels, because nicardipine (10(-7)M) and verapamil (10(-7)M) had no effects on ipriflavone-induced [Ca2+]i responses. [3H]Ipriflavone binding studies indicated the presence of specific ipriflavone binding sites (two classes), both in precursor cells [dissociation constant (Kd), 7.60 x 10(-8)M, 2.67 x 10(-6)M] and in mature osteoclasts (Kd, 4.98 x 10(-8)M, 3.70 x 10(-6)M). Specific ipriflavone binding was not displaced by various modulators of avian osteoclast function, such as estradiol (10(-8)M) or retinoic acid (10(-6)M), indicating that ipriflavone receptors differ from the receptors for these Ca-regulating hormones. The fusion of osteoclast precursor cells was significantly inhibited by ipriflavone, which led to dose-dependent inhibition of bone resorption and tartrate-resistant acid phosphatase activity. Novel specific ipriflavone receptors that are coupled to Ca2+ influx were demonstrated in osteoclasts and their precursor cells. These ipriflavone receptors may provide a mechanism to regulate osteoclast differentiation and function.


Assuntos
Cálcio/metabolismo , Osteoclastos/citologia , Osteoclastos/fisiologia , Receptores de Vitronectina/metabolismo , Fosfatase Ácida/antagonistas & inibidores , Animais , Remodelação Óssea , Reabsorção Óssea , Divisão Celular , Galinhas , Citosol/metabolismo , Feminino , Corantes Fluorescentes , Fura-2 , Isoenzimas/antagonistas & inibidores , Isoflavonas/metabolismo , Isoflavonas/farmacologia , Concentração Osmolar , Coelhos , Fosfatase Ácida Resistente a Tartarato
15.
J Neuroendocrinol ; 7(12): 917-22, 1995 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-8745269

RESUMO

Previous studies by us and others led us to hypothesize that there are separate LHRH pulse and surge generators in the rat brain. The present study was designed to detect the activity of LHRH pulse generator by checking changes in LH secretion and the multiunit activity (MUA) of the arcuate-median eminence region of the hypothalamus during infusions of naloxone (NAL, 2 mg/h) in the proestrous rat in which the LHRH surge generator activity was blocked by pentobarbital sodium (PB, 32 mg/kg bw, ip). The animals were subjected to blood sampling in the morning (1000-1300 h) or afternoon (1400-1700), and injected with PB at 09.45 or 13.45, respectively. During saline infusions in the rat given PB injection at either 09.45 or 13.45, serum LH levels were low but fluctuated significantly, suggesting a pulsatile secretion in either the morning or the afternoon period. The pulse intervals were an average 28.2 min in the morning and 42.2 min in the afternoon. NAL infusions decreased the pulse interval significantly, to 22.0 min in the morning and to 27.0 min in the afternoon. In the electrophysiological experiment, characteristic increases in the MUA (volleys), which occur in association with the initiation of an LH pulse and therefore are considered to represent an increased activity of the LHRH pulse generator, appeared during NAL (5 mg/h) infusions in either the morning or the afternoon. These results strongly suggest that separate LHRH pulse and surge generators exist in the brain, and that, even during the critical period of proestrus, the activity of LHRH pulse generator is disclosed by PB, which, on the other hand, arrests the surge generator.


Assuntos
Núcleo Arqueado do Hipotálamo/fisiologia , Hormônio Liberador de Gonadotropina/metabolismo , Hormônio Luteinizante/metabolismo , Eminência Mediana/fisiologia , Naloxona/farmacologia , Pentobarbital/farmacologia , Proestro , Animais , Núcleo Arqueado do Hipotálamo/efeitos dos fármacos , Ritmo Circadiano , Estimulação Elétrica , Feminino , Infusões Intravenosas , Hormônio Luteinizante/sangue , Eminência Mediana/efeitos dos fármacos , Naloxona/administração & dosagem , Proestro/efeitos dos fármacos , Radioimunoensaio , Ratos , Ratos Wistar
16.
Rinsho Shinkeigaku ; 35(6): 657-60, 1995 Jun.
Artigo em Japonês | MEDLINE | ID: mdl-8521644

RESUMO

A 21-year-old male patient with hereditary pressure-sensitive neuropathy (HPSN) is reported. He had been well and was working as a carpenter until February 6, 1993, when he developed difficulty in raising his left arm and numbness in the radial aspect of his left forearm in the morning. Left musculocutaneous nerve palsy, a left winged-scapula, absence of the left biceps and right Achilles reflexes, and distal dominant nerve conduction delay were positive findings. His father and younger brother showed similar conduction delays. Sural nerve biopsy revealed the presence of tomacula, segmental demyelination and thinly myelinated fibers. Gene analyses of the patient's cultured lymphoblastoid cells disclosed deletion of the marker 6G1 and peripheral myelin protein-22 (PMP-22) gene of a single allele of chromosome 17 in 90% of his intermitotic cells by in situ hybridization, and also a 57% gene dosage of PMP-22 of normal control using Southern blotting. These findings indicate the deletion in 17p11.2 of the genomic DNA of this patient, which is diagnostic for HPSN.


Assuntos
Deleção de Genes , Neuropatia Hereditária Motora e Sensorial/genética , Proteínas da Mielina/genética , Adulto , Cromossomos Humanos Par 17 , Neuropatia Hereditária Motora e Sensorial/patologia , Humanos , Masculino , Nervo Sural/patologia
17.
Virchows Arch ; 426(1): 43-50, 1995.
Artigo em Inglês | MEDLINE | ID: mdl-7704323

RESUMO

As clinicopathological features may not be sufficient to predict the progression of thymoma, we have carried out what we believe to be the first immunohistochemical study describing the relationship between the different types of thymoma and the tumour stage, on the one hand, and the expression of epidermal growth factor (EGF), EGF-receptor (EGFR), p53, v-erb B and ras p21, on the other. The positive rates versus histological types and Masaoka's clinical stages in the 47 cases were as follows: p53 (non-invasive thymoma: 41.7%; malignant thymoma category I: 82.4%; malignant thymoma category II: 83.3%), EGF (non-invasive thymoma: 4.2%; malignant thymoma category I: 11.8%; malignant thymoma category II: 33.3%) and EGFR (non-invasive thymoma: 8.3%; malignant thymoma category I: 35.3%; malignant thymoma category II: 66.7%); p53 (stages I and II: 51.7%; stages III and IV: 77.8%), EGF (stages I and II: 3.4%; stages III and IV: 22.2%) and EGFR (stages I and II: 13.8%; stages III and IV: 44.4%). These data suggest that p53 may be implicated in the initial stages of tumorigenesis and that increased expression of EGF and EGFR may play a role in thymoma progression.


Assuntos
Fator de Crescimento Epidérmico/análise , Receptores ErbB/análise , Timoma/classificação , Proteína Supressora de Tumor p53/análise , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Imuno-Histoquímica , Masculino , Pessoa de Meia-Idade , Proteína Oncogênica p21(ras)/análise , Proteínas Oncogênicas v-erbB/análise , Timoma/química
18.
Horm Behav ; 28(4): 424-30, 1994 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-7729810

RESUMO

The role of GABA neurons in the control of the surge of LH secretion was investigated by examining whether GABAA receptor antagonist bicuculline (BIC) infusion prior to the LH surge could advance the timing of the proestrous surge in the rat. The effect of the opioid receptor antagonist naloxone (NAL) was also examined for comparison. Female rats in proestrus were iv infused with NAL (2 or 5 mg/hr) or BIC (50 mg/kg/hr) for a 3-hr (1000-1300 hr) period during which blood samples were collected at 6-min intervals through an intraatrial cannula in freely moving rats. The animals that received infusion were bled again over a 7-hr period (1400-2000 hr) at 1-hr intervals. NAL infusions at 2 mg/hr induced an increase in pulsatile LH secretion, but did not affect the timing, magnitude, and duration of the LH surge. NAL infusions at 5 mg/hr not only induced a greater increase in pulsatile LH secretion but also resulted in a pronounced LH surge prematurely. In contrast, during BIC infusion, no significant changes in LH secretion were seen until 1200 hr, but afterward a rapid and sharp rise in LH secretion occurred, suggesting the premature LH surge. These results are consistent with the hypothesis that the tonic LH secretion is sensitive to NAL, but not to BIC, whereas the surge of LH secretion is sensitive to barbiturates that have been known as the activator of GABAA receptor complex. Therefore, we suggest that there is a LHRH surge generator, distinct from the pulse generator, in the brain, and it has GABA neurons in its circuitry.


Assuntos
Bicuculina/farmacologia , Encéfalo/efeitos dos fármacos , Hormônio Luteinizante/sangue , Naloxona/farmacologia , Proestro/efeitos dos fármacos , Animais , Encéfalo/fisiologia , Ritmo Circadiano/efeitos dos fármacos , Ritmo Circadiano/fisiologia , Estrogênios/fisiologia , Feminino , Injeções Intraventriculares , Neurônios/efeitos dos fármacos , Neurônios/fisiologia , Proestro/fisiologia , Ratos , Ratos Wistar , Receptores de GABA-A/efeitos dos fármacos , Receptores de GABA-A/fisiologia , Receptores Opioides/efeitos dos fármacos , Receptores Opioides/fisiologia
19.
J Protein Chem ; 13(8): 715-22, 1994 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-7710661

RESUMO

To study the structural organization of the main extracellular domain of the nicotinic acetylcholine receptor (AChR) alpha subunit in live muscle cells, we examined the native membrane-bound receptors in cultured mouse skeletal muscle cells for their ability to bind a panel of antibodies against uniform-sized overlapping synthetic peptides which collectively represent this entire domain. The binding profile indicated that the regions alpha 23-49, alpha 78-126, alpha 146-174, and alpha 182-210 are accessible to binding with antibody. Residues alpha 23-49, alpha 78-126, and alpha 194-210 contain binding regions for alpha-neurotoxin and some myasthenia gravis autoantibodies. A comparison of this binding profile with the profile obtained for membrane-bound Torpedo californica AChR in isolated membrane fractions showed some similarities as well as significant differences between the subunit organization in the isolated membrane fraction and that in the membrane of live muscle cells. Regions alpha 89-104 and alpha 158-174, which are exposed in the isolated membrane fraction, are also exposed in the live cell. On the other hand, regions alpha 23-49, and alpha 182-210, which are exposed in the live cell, are not accessible in the isolated membrane and, furthermore, the region alpha 1-16, which has marginal accessibility in the cell, becomes highly accessible in the membrane isolates. The exposed regions defined by this study may be the primary targets for the initial autoimmune attack on the receptors in experimental autoimmune myasthenia gravis.


Assuntos
Músculos/metabolismo , Receptores Nicotínicos/química , Sequência de Aminoácidos , Animais , Anticorpos/metabolismo , Especificidade de Anticorpos , Sítios de Ligação , Membrana Celular/metabolismo , Células Cultivadas , Camundongos , Dados de Sequência Molecular , Peptídeos/metabolismo , Conformação Proteica , Alinhamento de Sequência
20.
Endocr J ; 41(5): 559-63, 1994 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-7889117

RESUMO

To gain a better understanding of the existence of an ultra-short feedback mechanism controlling LHRH secretion in the medial preoptic area (MPO), we examined the effects of microinjections of LHRH or the LHRH antagonist [D-pGlu1, D-Phe2, D-Try3,6] into the MPO on pulsatile secretion of LH in ovariectomized rats and on the surge of LH secretion in proestrous rats. Neither the injection of 10 ng LHRH nor 100 ng its antagonist into the MPO had any effect on pulse frequency or the mean LH concentration in ovariectomized rats. The injection of 100 ng LHRH antagonist or 10 ng LHRH delayed or advanced, respectively, the LH surge in proestrous rats. Taking these results together with our previous report, the present study indicates that 1) endogenous LHRH in the MPO is involved in the ultra-short feedback regulation of LHRH release and 2) the ultra-short positive feedback mechanism in the MPO acts at the time of the proestrous LH surge but not under a hormonal milieu as in ovariectomized rats.


Assuntos
Hormônio Liberador de Gonadotropina/análogos & derivados , Hormônio Liberador de Gonadotropina/farmacologia , Hormônio Luteinizante/metabolismo , Área Pré-Óptica/fisiologia , Animais , Retroalimentação , Feminino , Hormônio Liberador de Gonadotropina/administração & dosagem , Hormônio Liberador de Gonadotropina/antagonistas & inibidores , Microinjeções , Ovariectomia , Fluxo Pulsátil , Ácido Pirrolidonocarboxílico/análogos & derivados , Ratos , Ratos Wistar
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