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Two Brazilian hydropower plants (Jupiá and Porto Primavera) located in the same watershed were explored in terms of the global resources needed to support these enterprises using a donor-side approach. Emergy theory and methods although commonly used by environmental scientists, may seem difficult to interpret for policy and decision-makers. Because of this, the possibility of transforming emergy flows and indices into money and area measures is explored in the present paper. Both hydropower plants deliver the same power and rely on practically the same infrastructure but involve very different flooded areas. Indirect areas calculated in terms of emergy show the different spatial distribution of resources. Some realistic alternatives for development were explored from both environmental and economic perspectives by using the emergy investment ratio and taking into account the matching between the enterprises emergy flows and the regional ones. [ABSTRACT FROM AUTHOR]

Abstract: Negative myoclonus (NM) is an unspecific motor disorder that can characterize a variety of neurological conditions. From the clinical point of view, NM appears as a shock-like involuntary jerky movement caused by a sudden, brief interruption of muscle activity. Asterixis is a type of NM that occurs typically in toxic-metabolic encephalopathies. NM of epileptic nature, or epileptic negative myoclonus (ENM), is defined as an interruption of tonic muscle activity, which is time-locked to an epileptic EEG abnormality, without evidence of an antecedent positive myoclonia in the agonist–antagonist muscles. ENM can be observed in idiopathic, cryptogenic, and symptomatic epileptic disorders. Pathophysiological hypotheses on the origin of NM involve subcortical as well as cortical mechanisms. Recent neuroimaging and neurophysiologic investigations, including intracerebral recordings and electrical stimulation procedures in epileptic patients, suggest the participation of premotor, primary motor, primary sensory, and supplementary motor areas in the genesis of NM. Polygraphic monitoring is essential for the diagnosis of NM, allowing the demonstration of brief interruptions of a tonic EMG activity, not preceded by a positive myoclonus in the agonist and antagonist muscles of the affected limb. Simultaneous EEG-EMG monitoring demonstrating the association of NM with an epileptic potential is consistent with the diagnosis of ENM. Evolution and prognosis of NM is mainly related to aetiology. In childhood idiopathic partial epilepsy, ENM can respond to some drugs (in particular, ethosuximide), whereas other medications (such as carbamazepine or phenytoin) have been reported to induce or worsen it. [Copyright &y& Elsevier]

Seizures in newborns do not always show a clear electro-clinical correlation. The real epileptic nature of some stereotyped rhythmic movements, included in the 'subtle seizures' and considered as brainstem release phenomena, is still debated. We report a brain injured newborn, who displayed several episodes of repetitive limb movements. The ictal EEG discharge, during one of these episodes, was associated with a motor pattern modification, which was endowed with quadrupedal locomotion kinematic features. This might represent an indirect evidence of cervical and lumbar Central Pattern Generators interconnection with in-phase coordination between diagonal limbs since the first hours of life in humans. [ABSTRACT FROM AUTHOR]

Objective Mutations in SCARB2 were recently described as causing action myoclonus renal failure syndrome (AMRF). We hypothesized that mutations in SCARB2 might account for unsolved cases of progressive myoclonus epilepsy (PME) without renal impairment, especially those resembling Unverricht-Lundborg disease (ULD). Additionally, we searched for mutations in the PRICKLE1 gene, newly recognized as a cause of PME mimicking ULD. Methods We reviewed cases of PME referred for diagnosis over two decades in which a molecular diagnosis had not been reached. Patients were classified according to age of onset, clinical pattern, and associated neurological signs into 'ULD-like' and 'not ULD-like.' After exclusion of mutations in cystatin B (CSTB), DNA was examined for sequence variation in SCARB2 and PRICKLE1. Results Of 71 cases evaluated, 41 were 'ULD-like' and five had SCARB2 mutations. None of 30 'not ULD-like' cases were positive. The five patients with SCARB2 mutations had onset between 14 and 26 years of age, with no evidence of renal failure during 5.5 to 15 years of follow-up; four were followed until death. One living patient had slight proteinuria. A subset of 25 cases were sequenced for PRICKLE1 and no mutations were found. Interpretation Mutations in SCARB2 are an important cause of hitherto unsolved cases of PME resembling ULD at onset. SCARB2 should be evaluated even in the absence of renal involvement. Onset is in teenage or young adult life. Molecular diagnosis is important for counseling the patient and family, particularly as the prognosis is worse than classical ULD. Ann Neurol 2009;66:532-536 [ABSTRACT FROM AUTHOR]

Studies atypical familial motor neuropathy in patients with the mutant transthyretin gene (TTR) Ile68Leu. Sample medical cases on the issue; Familial occurrence of axonal and slowly progressive polyneuropathy; Implications on studies of protein folding disorders.

Objective: To investigate ictal motor inhibition occurring during seizures in a patient with a tumor located in the left fronto-mesial pre-central cortex.Methods: Awake and sleep video-polygraphic monitoring, recording scalp EEG and EMG activities from several cranial, trunk and limbs muscles, was performed in a patient with drug-resistant recurrent focal motor seizures before surgical treatment. Speech/motor tasks were repeatedly administered to the patient during the recording sessions in order to evaluate the occurrence of early ictal motor inhibition.Results: Thirty-four seizures were recorded during wakefulness showing a stereotyped pattern of inhibition of speech and voluntary movements followed by sequential activation of upper limb–trunk–lower limb muscles contralateral to the tumor. Polygraphic recordings showed that: (1) initial speech and motor arrest were associated with the EMG evidence of progressive muscle tone suppression in cranial and right distal upper limb muscles; (2) tonic contraction of right deltoid, biceps brachii, intercostalis and paraspinalis muscles appeared after motor inhibition; (3) tonic-clonic activity in the right tibialis anterior muscle occurred at the end of seizures. Eleven subclinical seizures were recorded during sleep showing mild focal tonic EMG activity in right side trunk muscles.Conclusions: Our findings evidenced early and somatotopically organized inhibition of voluntary movement at the beginning of epileptic seizures with fronto-mesial onset. The demonstration that speech and motor arrest were associated with progressive EMG suppression in cranial and limb muscles supports the hypothesis of motor inhibitory seizures originating in the mesial aspect of pre-motor frontal cortex. [Copyright &y& Elsevier]

We describe the structure, genomic organization, and some transcription features of a human brain-specific gene previously localized to the genomic region involved in temporal lobe epilepsy and spastic paraplegia on chromosome 10q24. The gene, which consists of six exons disseminated over 16 kb of genomic DNA, is highly homologous to the porcine tmp83.5 gene and encodes a putative transmembrane protein of 141 amino acids. Unlike its porcine homolog, from which two mRNAs with different 5′-sequences are transcribed, the human gene apparently encodes three mRNA species with 3′-untranslated regions of different sizes. Mutation analysis of its coding sequence in families affected with temporal lobe epilepsy or spastic paraplegia linked to 10q24 do not support the involvement of this gene in either diseases. [Copyright &y& Elsevier]