Uroguanylin induces electroencephalographic spikes in rats.

Uroguanylin (UGN) is an endogenous peptide that acts on membrane-bound guanylate cyclase receptors of intestinal and renal cells increasing cGMP production and regulating electrolyte and water epithelial transport. Recent research works demonstrate the expression of this peptide and its receptor in the central nervous system. The current work was undertaken in order to evaluate modifications of electroencephalographic spectra (EEG) in anesthetized Wistar rats, submitted to intracisternal infusion of uroguanylin (0.0125 nmoles/min or 0.04 nmoles/min). The current observations demonstrate that 0.0125 nmoles/min and 0.04 nmoles/min intracisternal infusion of UGN significantly enhances amplitude and frequency of sharp waves and evoked spikes (p = 0.03). No statistical significance was observed on absolute alpha and theta spectra amplitude. The present data suggest that UGN acts on bioelectrogenesis of cortical cells by inducing hypersynchronic firing of neurons. This effect is blocked by nedocromil, suggesting that UGN acts by increasing the activity of chloride channels.

Motor neuron diseases in the university hospital of Fortaleza (Northeastern Brazil): a clinico-demographic analysis of 87 cases.

In this retrospective (1980-1998) study, we have analyzed clinico-demographically, from the records of the University Hospital of Fortaleza (Brazil), a group of 87 patients showing signs and symptoms of motor neuron diseases (MNDs). Their diagnosis was determined clinically and laboratorially. The WFN criteria were used for amyotrophic lateral sclerosis (ALS) diagnosis. The clinico-demographic analysis of the 87 cases of MNDs showed that 4 were diagnosed as spinal muscular atrophy (SMA), 5 cases as ALS subsets: 2 as progressive bulbar paralysis (PBP), 2 as progressive muscular atrophy (PMA) and 1 as monomelic amyotrophy (MA), and 78 cases of ALS. The latter comprised 51 males and 27 females, with a mean age of 42.02 years. They were sub-divided into 4 groups according to age: from 15 to 29 years (n= 17), 30 to 39 years (n= 18), 40 to 69 years (n= 39) and 70 to 78 years (n= 4). From the 78 ALS patients, 76 were of the classic sporadic form whilst only 2 were of the familial form. The analysis of the 87 patients with MNDs from the University Hospital of Fortaleza showed a predominance of ALS patients, with a high number of cases of juvenile and early onset adult sporadic ALS.

Epilepsia partialis continua (Koshevnikov): a preliminary case report.

We report on the preliminary clinical and electrophysiological aspects of an in-patient possibly presenting epilepsia partialis continua (Koshevnikov). We discuss the different etiologies and emphasize on the possible idiopathic form in this case.

Partial sequence and toxic effects of granulitoxin, a neurotoxic peptide from the sea anemone Bunodosoma granulifera

A neurotoxic peptide, granulitoxin (GRX), was isolated from the sea anemone Bunodosoma granulifera. The N-terminal amino acid sequence of GRX is AKTGILDSDGPTVAGNSLSGT and its molecular mass is 4958 Da by electrospray mass spectrometry. This sequence presents a partial degree of homology with other toxins from sea anemones such as Bunodosoma caissarum, Anthopleura fuscoviridis and Anemonia sulcata. However, important differences were found: the first six amino acids of the sequence are different, Arg-14 was replaced by Ala and no cysteine residues were present in the partial sequence, while two cysteine residues were present in the first 21 amino acids of other toxins described above. Purified GRX injected ip (800 µg/kg) into mice produced severe neurotoxic effects such as circular movements, aggressive behavior, dyspnea, tonic-clonic convulsion and death. The 2-h LD50 of GRX was 400 ñ 83 µg/kg

Partial sequence and toxic effects of granulitoxin, a neurotoxic peptide from the sea anemone Bundosoma granulifera.

A neurotoxic peptide, granulitoxin (GRX), was isolated from the sea anemone Bunodosoma granulifera. The N-terminal amino acid sequence of GRX is AKTGILDSDGPTVAGNSLSGT and its molecular mass is 4958 Da by electrospray mass spectrometry. This sequence presents a partial degree of homology with other toxins from sea anemones such as Bunodosoma caissarum, Anthopleura fuscoviridis and Anemonia sulcata. However, important differences were found: the first six amino acids of the sequence are different, Arg-14 was replaced by Ala and no cysteine residues were present in the partial sequence, while two cysteine residues were present in the first 21 amino acids of the other toxins described above. Purified GRX injected i.p. (800 micrograms/kg) into mice produced severe neurotoxic effects such as circular movements, aggressive behavior, dyspnea, tonic-clonic convulsion and death. The 2-h LD50 of GRX was 400 +/- 83 micrograms/kg.

An association of central post-stroke pain and thalamic hand.

Thalamic hand is one of the clinical expressions of the painful thalamic syndrome. This paper relates on a case of a patient with a syndrome of central post-stroke and supra-thalamic pain who also presents a thalamic hand. The authors emphasize the notion that in the syndrome of central post-stroke pain a direct or indirect (infra or supra)-thalamic lesion seems to be an essential element for the genesis of central pain.

An association of central post-stroke pain and thalamic hand

A mäo talâmica é um dos sinais clínicos na síndrome talâmica. Neste estudo é relatado o caso de uma paciente com síndrome de dor central (supratalamica) pos-ictal que apresenta também mäo talâmica. Os autores enfatizam a noçäo de que na síndrome de dor central pos-ictal, uma lesäo talâmica direta ou indireta (infra ou supratalâmica) é elemento fundamental para a gênese da dor central

Tropical spastic paraparesis in Northeastern Brazil.

Ten possible cases of tropical spastic paraparesis (TSP) in Northeastern Brazil (Ceará) are presented. They show the typical symptoms and signs of TSP consisting of weakness of the lower limbs, spastic gait, hyperreflexia, bladder dysfunction and variable signs of posterior columns impairment. The laboratory examinations excluded other compressive, infective, degenerative or demyelinating lesions of their spinal cord. Our patients age ranged from 21 to 59 years, all were of black origin and all were of lower social class. There was a slight preponderance of females. An etiological implication of a retrovirus (HTLV-I) has been shown for TSP, but for lack of technical conditions we could not determine it in our patients, and that stands as our subsequent step in those and further cases.

[A case of bilateral tonic pupil (Holmes-Adie syndrome)]. / A propósito de um caso de pupila tônica bilateral (síndrome de Holmes-Adie).

The authors present a case of bilateral tonic pupil and discuss clinical and physiopathological aspects of this syndrome. They discuss some elements necessary for the understanding of the etiopathogenesis of the disease.

A proposito de um caso de pupila tonica bilateral (sindrome de Holmes-Adie). / Apropos of a case of bilateral tonic pupil (Holmes-Adie's syndrome

Os autores apresentam um caso de pupila tonica e discutem aspectos clinicos e fisiopatologicos dessa sindrome. Eles fazem consideracoes sobre lacunas na compreensao da etiopatogenia da sindrome