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Hallervorden-Spatz syndrome (HSS) is a neurodegenerative disorder characterized by progressive dementia, dystonia, ataxia, and rigidity. An atypical form of adult-onset HSS was observed in a 36-year-old man presenting with progressive dysarthria. Markedly dysarthric speech and a weak atrophic tongue associated with a neurogenic pattern of motor unit recruitment in bulbar-supplied muscles on electromyography led to an initial impression of bulbar amyotrophic lateral sclerosis (ALS). Lack of expected progression of symptoms, however, prompted reinvestigation. Repeat brain magnetic resonance imaging demonstrated an "eye-of-the-tiger" pattern in the basal ganglia, characteristic of HSS, thus requiring genetic studies. DNA analyses of the pantothenate kinase gene (PANK2) was conducted and revealed two novel, disease-causing exon 3 missense mutations (Cys231Ser and Tyr251Cys). This case broadens the genotypic and phenotypic spectrum of HSS to include a late-onset syndrome resembling bulbar-onset ALS.

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A patient was diagnosed in 1974 with the unique combination of Leber hereditary optic neuropathy (LHON) and spondyloepiphyseal dysplasia. The entire mitochondrial DNA (mtDNA) sequence from this patient was determined in order to identify candidate pathogenic mutations. The patient's mtDNA carried the LHON mutation at nucleotide 14484, thus elucidating the etiology of his optic neuropathy. We also identified another ND6 mutation at nucleotide 14420. This latter mutation is probably a clinically benign private polymorphism, although a pathogenic role in his skeletal abnormalities or in his optic neuropathy cannot yet be ruled out.

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One of the most significant developments in biology in the past half century was the emergence, in the late 1950s and early 1960s, of neuroscience as a distinct discipline. We review here factors that led to the convergence into a common discipline of the traditional fields of neurophysiology, neuroanatomy, neurochemistry, and behavior, and we emphasize the seminal roles played by David McKenzie Rioch, Francis O Schmitt, and especially Stephen W Kuffler in creating neuroscience as we now know it. The application of the techniques of molecular and cellular biology to the study of the nervous system has greatly accelerated our understanding of the mechanisms involved in neuronal signaling, neural development, and the function of the major sensory and motor systems of the brain. The elucidation of the underlying causes of most neurological and psychiatric disorders has proved to be more difficult; but striking progress is now being made in determining the genetic basis of such disorders as Alzheimer's disease, amyotrophic lateral sclerosis, Parkinson's disease, and a number of ion channel and mitochondrial disorders, and a significant start has been made in identifying genetic factors in the etiology of such disorders as manic depressive illness and schizophrenia. These developments presage the emergence in the coming decades of a new nosology, certainly in neurology and perhaps also in psychiatry, based not on symptomatology but on the dysfunction of specific genes, molecules, neuronal organelles and particular neural systems.

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The dual signal hypothesis of apoptosis holds that a common signal can activate both apoptotic and proliferative pathways. The fate of a cell is dependent on which of these two pathways predominates. In the MAPK family of kinases, ERK and JNK have been proposed to mediate apoptosis whereas the PI3K-stimulated kinase, Akt/PKB, has been shown to inhibit apoptosis. The object of this study was to determine the role of these kinases in a glioma model of apoptosis. We have previously shown that K252a induces apoptosis and inhibits kinase activity. In this study we confirm these results and show that the protein tyrosine phosphatase inhibitor sodium vanadate activates ERK, JNK and Akt/PKB, but does not stimulate proliferation. Vanadate did protect T98G cells from K252a-induced apoptosis, an effect that was abolished by addition of the PI3K inhibitor wortmannin. This suggests that PI3K and Akt/PKB may be responsible for mediating vanadate's protective effect on glioma cells. We conclude that the intracellular balance between protein phosphorylation pathways is a critical determinant of both cell proliferation and cell death.

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Apoptosis is a carefully regulated process involved in developmental and immunological events. The alteration of apoptotic pathways is important in the establishment and progression of neoplasia. Apoptosis allows for the orderly removal of excess cells but, in contrast to necrosis, it is not an inflammatory process. Many of the molecular components and effectors of apoptosis have been described. In this review the authors briefly discuss the current understanding of apoptosis in the context of the two prevailing hypotheses, the "conflicting signal" and "dual signal" theories.

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We present 3 new cases of cervical epidural abscess (CEA), a rare condition, along with a review of 12 other case reports. The average patient age was 45 years; just over half were male. The abscesses usually involved the mid to lower cervical region and extended an average of three to four segments. Neck stiffness was present in all patients; root pain and paresthesias were present less often. Weakness of one to four extremities developed in all but one patient. Sensory levels were frequently present, sometimes below the site of the lesion. All but two patients were febrile. All but two had elevated CSF protein, and all but two had a pleocytosis; myelography always revealed a complete or partial block. Staphylococcus aureus was the causative organism in 8 of 11 patients. CEA should be considered in a patient with neck stiffness, paresthesias, and/or radicular pain so that CT or myelography followed by surgical decompression and/or antimicrobial drugs can be initiated before prolonged weakness develops. One of our patients developed a syrinx causing a new neurologic deficit 3 years after treatment. Delayed syringomyelia, a rare complication of extramedullary lesions, lends support to vascular occlusion as the major mechanism of damage in epidural abscess.

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A retrospective analysis of 10 adult patients with community-acquired Staphylococcus aureus meningitis was performed in order to elucidate the characteristics and treatment of this lethal disease. In all patients, a focus of infection outside the central nervous system was apparent at presentation. A poor prognosis was associated with severe underlying disease, greater degree of hyponatremia at presentation, development of seizures, failure of nuchal rigidity to develop, persistent or recurrent bacteremia, and the presence of concurrent S. aureus bronchopneumonia. Degree of deterioration in mental status and cerebrospinal fluid pleocytosis, protein levels, and glucose levels did not appear to have any prognostic significance. Therapy with rifampin and a semisynthetic penicillin effected a cure in all six patients treated with this regimen. In contrast, three of four patients treated with other antibiotic combinations died. On the basis of this experience, it is concluded that further trials with rifampin in combination with another anti-staphylococcal antibiotic for the treatment of S. aureus meningitis are warranted.

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A young woman with 12 separate brain abscesses was treated medically after aspiration of one abscess for diagnostic bacteriological examination. She made an excellent recovery with only minimal residual neurological dysfunction. Surgical aspiration for detailed bacteriological studies followed by appropriate antimicrobial therapy is an effective way of treating multiple brain abscesses in the neurologically stable patient.

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Sera of normal subjects and patients wtih multiple sclerosis (MS) have been frequently found to contain picomolar quantities of endogenous myelin basic protein-serum factors (MBP-SFs). These serum factors, collectively representing a heterogeneous spectrum, were detected and measured by means of a competitive inhibition radioimmunoassay (RIA) designed to distinguish their respective binding affinities with anti-MBP reagent antiserum. Anti-MBP antibodies in these same normal and patient sera were also detected and their differing binding affinities determined. In general, when sera of normal subjects were found to contain free MBP-SFs, the reagent anti-MBP antibodies in the reagent antiserum used to detect them were of relatively high binding affinity (8 X 10(8) M-1). When normal sera were found to contain free anti-MBP antibodies, the affinities of such antibodies were invariably lower (0.06-0.7 X 10(8) M-1). In contrast, sera of patients with active MS and exhibiting clinical fluctuations in their disease, infrequently contained high or medium high affinity MBP-SFs, whereas higher affinity anti-MBP antibodies were commonly detected. These patterns of MBP-SFs and anti-MBP antibodies in normal and MS human sera resemble those previously observed in studies of normal Lewis rats and rats developing experimental allergic encephalomyelitis (EAE). The findings here reported provide additional support for the view that circulating endogenous MBP-SFs may function as neuroautotolerogens that restrict expansion of MBP-reactive lymphoid cell clones having potentially injurious effector activity for central nervous system (CNS) tissue.

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An acute febrile illness with pulmonary infiltration and severe cerebellar deficit developed in a woman. The diagnosis of Legionnaires' disease was confirmed by indirect fluorescent antibody tests. Legionnaires' disease should be considered as a diagnostic possibility in patients with pneumonia and cerebellar dysfunction.

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