H J van der Helm

INTRACELLULAR LOCALIZATION OF GLUTAMATE DECARBOXYLASE, γ-AMINOBUTYRATE TRANSAMINASE AND SOME OTHER ENZYMES IN BRAIN TISSUE

IN studying the intracellular localization of glutamate decarboxylase (GAD, E.C. 4.1.1.15) in brain tissue of the rat, LDVTRUP (1961) and HILGERSOM (1962) could not detect any considerable amount of this enzyme in the mitochondrial fraction. SALGANICOFF and DE ROBERTIS (1963) prepared a mitochondrial fraction containing approximately 40 per cent of the GAD and 70-80 per cent of the y-aminobutyrate transaminase (GABAT, E.C. 2.6. I.-). By analysing this mitochondrial fraction on discontinous sucrose gradients, these authors showed the localization of both enzymes to be different. They suppose GABAT to be localized in mitochondria and GAD in nerve-endings. In view of the conflicting data on the intracellular localization of GAD we thought it desirable to reinvestigate this problem, including GABAT in the the analysis. The mitochondrial fraction was further studied by using centrifugation on continuous sucrose gradients, this technique being more refined than those used by DE ROBERTIS, PELLEGRINO DE IRALDI, RODRIGUEZ DE LORES ARNAIZ and SALGANICOFF (1 962) and WHITTAKER (1959). In all of the fractions cytochrome oxidase (E.C. 1.9.3.1), aspartate transaminase (GOT, E.C. 2.6.1. l), alanine transaminase (GPT, E.C. 2.6.1.2), lactate dehydrogenase (LDH, E.C. 1.1.1.27), alkaline phosphatase (E.C. 3.1.3.1), acid phosphatase (E.C. 3.1.3.2) and protein, were measured. and H. VELDSTRA*

Spinocerebellar degeneration: hexosaminidase A and B deficiency in two adult sisters.

Two adult sisters had spinocerebellar degeneration. Biochemical studies revealed a very low activity of both fraction A and fraction B of the lysosomal enzyme, hexosaminidase, in serum and leukocytes. A skin biopsy showed lesions suggestive of neuronal storage disease. The disorder seems to be an adult form of GMz gangliosidosis.

Effect of early and late syphilis on central nervous system: cerebrospinal fluid changes and neurological deficit.

Neurological examination and investigation of the cerebrospinal fluid (CSF) was performed on 24 patients with early and 180 patients with late syphilis. In 21 (12%) patients with late syphilis positive CSF treponemal test results and neurological deficits suggestive of symptomatic neurosyphilis were found. Concomitantly all but three patients with neurosyphilis showed one or more of the following abnormal CSF variables: CSF concentration of albumin X 10(3)/serum concentration (albumin ratio) greater than or equal to 7.9; mononuclear cells greater than 5 microliters: ratio of CSF to serum IgG concentrations/ratio of CSF to serum albumin concentrations (IgG index) greater than or equal to 0.7 or of IgM/albumin (IgM index) greater than or equal to 0.1; or oligoclonal CSF immunoglobulins. In 20 (95%) patients with neurosyphilis evidence of the production of treponemal antibodies within the central nervous system (CNS) was shown. Ten (48%) patients with neurosyphilis had been treated previously for late syphilis. These observations emphasise the need to screen for neurosyphilis in patients with late syphilis. Intrathecal production of treponemal antibodies was detected in six (25%) patients with early and 44 (28%) with late syphilis who did not show any neurological deficit. Intrathecal production of treponemal antibodies indicating that the CNS was affected led us to suspect asymptomatic neurosyphilis in these patients. Seventeen (11%) patients with late syphilis but no neurosyphilis and only one (4%) with early syphilis showed additional abnormal CSF variables. Surprisingly, six out of 22 patients with treated early and 20 out of 68 patients with treated late syphilis showed evidence of treponema antibody production within the CNS. We do not know whether these findings indicate that the CNS was affected because of inadequate treatment or merely reflect persistent synthesis of treponemal antibodies associated with cured infection. In one (4%) patient with early and in 21 (13%) with late syphilis but no neurosyphilis abnormal CSF variables in the absence of positive CSF treponemal test results were observed, which excluded syphilitic inflammation of the CNS.

Analysis of heroin in relation to illicit drug traffic.

Abstract The quantitative composition of 32 illicit heroin samples was determined. It seemed to be possible to draw conclusions about the common origin or common trade route of different samples.

Suppression of the development of experimental allergic encephalomyelitis by suramin

Suramin was tested for its ability to suppress experimental allergic encephalomyelitis. Prophylactic administration caused significant reduction in the severity of the disease, incidence of paralysis and cellular infiltration in nervous tissue. Therapeutic treatment with suramin also caused a reduction in the severity of the disease, the incidence of paralysis and cellular infiltration, but to a lesser extent. Significantly fewer animals were paralysed for more than two days on therapeutic treatment.

Comparison of the spectrophotometric determination and the two-stage coagulation assay of tissue factor activity

The tissue factor activity of human brain thromboplastin and 6 commercial thromboplastins was determined by a spectrophotometric method and a two-stage coagulation assay. The thromboplastins were incubated with an excess of Factor VII and Factor X, and the activation of Factor X was estimated from the rate of hydrolysis of the chromogenic substrate S-2222 and from the coagulation time of plasma enriched in phospholipids. The results obtained by the two methods were related linearly and showed a correlation coefficient of 0.89. The coefficient of variation was 11% in the spectrophotometric method and 25% in the two-stage coagulation assay.

Radioimmunoassay of Immunoglobulins in Cerebrospinal Fluid

In several neurological diseases abnormalities of immunoglobulin G in cerebrospinal fluid (CSF) are observed. These abnormalities can be qualitative (1) (restricted heterogeneity of IgG) and quantitative (2) (increased concentration of IgG in CSF). There are four other classes of immunoglobulins: IgA, IgM, IgD and IgE, some of which have particular functions. It will be of interest to obtain information on these immunoglobulins in CSF in order to arrive at a better understanding of immune-processes in neurological disease. Since the normal concentrations of IgM, IgA, IgD and IgE in CSF are much lower than that of IgG these immunoglobulins can only be measured by very sensitive assay methods, unless CSF is concentrated first.

The protein composition of the cerebrospinal fluid in acute necrotizing encephalitis An agar gel electrophoretic and immunoelectrophoretic study

SUMMARYThe results of agar electrophoretic and immunoelectrophoretic studies of CSF proteins in acute necrotizing encephalitis are presented. Two of the 5 patients showed marked abnormalities in CSF protein composition, specifically a markedly increased gamma globulin fraction (up to 45%), 3 to 5 gamma subfractions, including one high-speed fraction, and reversal of the beta 1 to upsilon ratio. Immunoelectrophoresis disclosed an increase in medium-speed and high-speed IgG and IgA. The serum was characterized by an increase in alpha globulins and beta-2 globulin. No abnormalities of significance were found in the acute stage of illness. It is concluded that the duration of illness and the extent of the perivascular infiltrates are factors of significance in the occurrence of these severe changes in CSF protein composition in acute necrotizing encephalitis.SUMMARYThe results of agar electrophoretic and immunoelectrophoretic studies of CSF proteins in acute necrotizing encephalitis are presented. Two of the 5 patients showed marked abnormalities in CSF protein composition, specifically a markedly increased gamma globulin fraction (up to 45%), 3 to 5 gamma subfractions, including one high-speed fraction, and reversal of the beta 1 to upsilon ratio. Immunoelectrophoresis disclosed an increase in medium-speed and high-speed IgG and IgA. The serum was characterized by an increase in alpha globulins and beta-2 globulin. No abnormalities of significance were found in the acute stage of illness. It is concluded that the duration of illness and the extent of the perivascular infiltrates are factors of significance in the occurrence of these severe changes in CSF protein composition in acute necrotizing encephalitis.

Bhattacharya : a new application for quality control

The Bhattacharya method and the ‘average of normals’ method for internal quality control were compared. Both are based on unselected patient test results. The Bhattacharya method is mostly used in clinical chemistry for calculation of reference intervals but could be modified for quality control procedures. Using the data of a coagulation test and simulating systematic errors, it was concluded that the Bhattacharya method is more sensitive to expected shifts and is more flexible than the ‘average of normals’ method.

Elevated γ-Globulin Concentration of the Cerebrospinal Fluid in a Case of Uveomeningoencephalitis

The results of an agar electrophoretic CSF protein analysis in a case of uveomeningoencephalitis are presented. The CSF protein pattern in this case resembles those seen in neurological disorders with