Neurotoxicity of local administration of two nitrosoureas in malignant gliomas.

The neurotoxicity of local administration of nitrosoureas in malignant gliomas was investigated clinicopathologically. Twenty patients were entered into this study: 13 were treated with 1-(4-amino-2-methyl-5-pyrimidinyl)methyl-3-(2-chloroethyl)-3-nitrosourea hydrochloride (ACNU) and 7 with methyl 6-[3-(2-chloroethyl-3-nitrosoureido]-6-deoxy-alpha-D-glucopyranoside (MCNU). On the average, a single dose of 20 mg of ACNU was administered 15 times, for a total dose of 295 mg in each case, while a single dose of 11 mg of MCNU was given 2 times, for a total dose of 24 mg.

Sequential course of uptake of intravitreal 5,7-dihydroxytryptamine by carp retinal cells.

The sequential course of uptake by retinal cells of intravitreally injected 5,7-dihydroxytryptamine (5,7-DHT) together with dopamine (DA) was investigated in juvenile carp retinas, which were removed at various intervals (1-24 h) after injection. The cells taken up 5,7-DHT were visualized immunohistochemically with anti-serotonin (5-HT) antibody and FITC-conjugated IgG. After a mixture of 5,7-DHT and DA (2.

Histological, ultrastructural and chromatographical discrimination of phospholipids in meningiomas.

Phospholipids in meningiomas were studied by light and electron microscopy, and by high-performance liquid chromatography. They were microscopically demonstrated in six of the ten cases by Sudan III staining after the fixation with potassium dichromate. However, the conventional ultrastructural fixation with glutaraldehyde and osmium tetroxide failed to confirm phospholipids, as most of them were dissolved during dehydration.

Neurotoxic effects of L-alpha-aminoadipic acid on the carp retina: a long term observation.

The hypothesis has been tested that the enantiomers of alpha-aminoadipic acid have different target effects; the L-isomer has both glio- and neurotoxic actions, while the DL-isomer has a gliospecific action in the CNS. Electrophysiological and morphological studies were carried out on the retina of the carp (Cyprinus carpio) for one to two months after intraocular injection with alpha-aminoadipic acids at various doses. Intracellular recording from horizontal cells and extracellular recording of spike discharges from ganglion cells in isolated retinal preparations were made from control and pretreated retinas at various intervals after intraocular injection with the enantiomers.

Gliotoxic effects of alpha-aminoadipic acid isomers on the carp retina: a long term observation.

The glutamate analogue, alpha-aminoadipic acid was intravitreally administered in the D-, DL- and L-forms to carp (Cyprinus carpio) retina in vivo. To make a quantitative assessment of its gliotoxic action, the activity of glutamine synthetase, whose localization was confirmed in glial Müller cells by an immunohistochemical technique, was examined at various intervals over one month. Intravitreal injection of 8 mumol alpha-aminoadipic acids reduced the glutamine synthetase activity within 4 h and maximally by 24 h.

Pulmonary surfactant-like multilamellar bodies in human arachnoid villi.

Human arachnoid villi adequately treated with tannic acid before osmication ultrastructurally disclosed highly ordered multilamellar bodies in all of the 6 subjects studied. The multilamellar bodies were varied considerably in size and shape, but often showed a fingerprint-like appearance. They were found in the intercellular space, extracellular cisterns or microcores and within the cytoplasm of arachnoid cells.

Liberation of eosinophil granules in the inner capsule of chronic subdural hematomas.

The role of eosinophilic infiltration in the inner capsule was studied in 35 consecutive cases of chronic subdural hematomas. The eosinophilic infiltration in the inner capsule was microscopically observed in 10 of the 22 cases which were associated with the infiltration in the outer capsule. The majority of eosinophils were ultrastructurally fully granulated and contained numerous glycogen granules.

Dendritic morphology of retinal dopamine cells in carp of different sizes.

The dendritic morphology of dopamine (DA) cells in the inner plexiform layer of the retina of different-sized carp (8.6-33.6 cm in body length) was investigated by identifying their fluorescent cell bodies in isolated, aldehyde-fixed flatmounts and injecting them iontophoretically with Lucifer yellow (LY) under microscopic control.

A high performance liquid chromatography assay for glutamine synthetase.

A sensitive method for assaying glutamine synthetase activity is described. This enzyme produces ?-glutamylhydroxamate in the presence of l-glutamic acid and hydroxylamine as substrates. This amino acid hydroxamate was separated and quantified by high performance liquid chromatography on an ion-exchange resin column using post-column derivatization with o-phthalaldehyde for detection.

Effect of electro-motor stimulation on the power production of a maximally stretched muscle.

Unlabelled: The effect of electro-motor stimulation (EMS) upon the increase in power production of the tibialis anterior muscle (TA) of healthy individuals in both the maximally stretched (ST group) and shortened (SH group) positions was investigated. The effect of cross-education upon the contralateral muscle was also examined. EMS with a frequency of 50 hertz, a duration of 0.

Ultrastructural immunogold labelling of vimentin filaments on postembedding ultrathin sections of arachnoid villi and meningiomas.

An immunoelectron microscopic technique for the labelling of vimentin intermediate filaments on postembedding ultrathin sections is reported. Arachnoid villi obtained at autopsy and meningiomas at surgery were fixed in 1% paraformaldehyde for 30 minutes, embedded without postfixation in Epon-Araldite mixture and polymerized at 37 degrees C for 3 weeks. Ultrathin sections were etched in 2% KOH for 3 minutes and incubated with anti-vimentin monoclonal antibodies which were subsequently labelled with goat anti-mouse IgG coupled to colloidal golds.

Dopamine cells and rod bipolar cells contain protein kinase C-like immunoreactivity in some vertebrate retinas.

The localization of cells immunoreactive to a monoclonal antibody against protein kinase C (PKC) and to polyclonal antibodies against tyrosine hydroxylase (TH) was investigated in the retina of fish (carp, goldfish, dace and catfish), frog, turtle, chick and some mammalians (guinea pig, rat, cat and rabbit) by means of fluorescence microscopy. PKC-like immunoreactivity was found in dopamine (DA) or TH-like immunoreactive (IR) cells in all the species examined and also in rod bipolar cells in the fish (except for catfish), and in presumed rod bipolar cells in the other animals (except for frog and turtle). In the catfish, frog and turtle retinas, no PKC-like IR bipolar cells were found.

Effects of peripheral nerve stimulation on the blood flow of the spinal cord and the nerve root.

Hemodynamic changes in the spinal cord and the nerve root caused by electrical sciatic nerve stimulation in anesthetized dogs were measured with a thermal diffusion method. The electrical stimulation increased the blood flow of the stimulated spinal cord and the nerve root. The conditions of stimulation giving the maximum increase of blood flow were different for the spinal cord and the nerve root.

Removal of apolipoprotein E-enriched high density lipoprotein by LDL-apheresis in familial hypercholesterolaemia: a possible activation of the reverse cholesterol transport system.

The presence of apo E-containing HDL in familial hypercholesterolaemia was investigated and its removal by LDL-apheresis using a dextran sulphate cellulose column was demonstrated by measurement of the apo E/apo A-I molar ratio of serum and by nondenaturing polyacrylamide gel electrophoresis followed by immunoblotting. The molar ratios of apo E/apo A-I in the density greater than 1.063 kg/l fraction of serum obtained from two homozygous patients with familial hypercholesterolaemia were higher (0.

A light and electron microscopic and immunohistochemical study of human arachnoid villi.

The structure of human arachnoid villi was investigated by light and electron microscopy with the aid of immunohistochemical techniques. The human arachnoid villi examined were basically composed of four portions: a fibrous capsule, an arachnoid cell layer, a cap cell cluster, and a central core. The arachnoid cell layer encompassing the central core was mostly covered by the thin fibrous capsule with an endothelial investment.

Interindividual changes in volume of distribution of cefazolin in newborn infants and its prediction based on physiological pharmacokinetic concepts.

The purpose of this study was to investigate factors affecting the volume of distribution of cefazolin (a beta-lactam antibiotic) in newborn infants with bacterial infections, and to propose a method for predicting the volume of distribution at steady state per body weight (Vdss/BW). Cefazolin and tobramycin (an aminoglycoside) were simultaneously given to newborn infants (aged 2 to 28 d), and plasma concentration-time data were analyzed on the basis of model-independent moment analysis. The Vdss/BW values ranged from 0.

Terminal sprouting in partially denervated muscle of the mouse: a scanning electron microscopic study.

Terminal sprouting in the mouse gastrocnemius muscle was examined by scanning electron microscopy after partial denervation. After one of the two muscle nerves in the medial head was cut, terminal sprouts arose from the outer edge of the intact motor endplates and grew out onto a connective tissue layer on the muscle fibres. The sprouts were very slender along their length, although some had a varicose appearance.

Previously unreported "hemidesmosomal junctions" between folliculo-stellate cells and pituitary adenoma cells.

Thirty-eight non-functioning pituitary adenomas were ultrastructurally investigated with particular attention to the Folliculo-Stellate (FS) cells. A large number of FS cells were found in four cases, one of which disclosed a new type of intercellular junction between FS cells and surrounding adenoma cells. These junctions were characterized by 1) the presence of plasmalemmal attachment plaques only in FS cells, 2) the cytoplasmic filaments assembling in parallel to the attachment plaques, 3) the parallel plasma membranes being separated by the intercellular amorphous material and 4) the intercellular space of approximately 25 nm width.

Ultrastructural comparison of arachnoid villi and meningiomas in man.

An ultrastructural comparison of arachnoid villi and meningiomas was made in man. Human arachnoid villi basically consisted of four portions: fibrous capsule; arachnoid cell layer; cap cell cluster; and central core. Arachnoid cells had many characteristic structures in common with meningioma cells: plasmalemmal interdigitations; desmosomes; hemidesmosome-like junctions; and cytoplasmic filaments.

Functional ultrastructure of cerebrospinal fluid drainage channels in human arachnoid villi.

The functional ultrastructure of the human arachnoid villi was studied to clarify drainage channels of cerebrospinal fluid (CSF). The apical portion of each villus was usually covered by the arachnoid cell layer alone with no endothelial investment, whereas most of the stromal central core was further encompassed by a fibrous capsule with an endothelial investment. Accordingly, the CSF-blood interface was assumed to be in both the endothelial cells and the arachnoid cell layer.

Regional difference in the dendritic morphology of dopamine cells in carp retina.

The dendritic morphology of dopamine (DA) cells in the inner plexiform layer of the retina of carp (body length, ca. 33 cm) was investigated by identifying their fluorescent cell bodies in isolated, aldehyde-fixed flat-mounts and injecting them iontophoretically with Lucifer yellow CH under microscopic control. Attention was paid to clarifying regional differences in their dendritic morphology.

GABAergic inhibition on dopamine cells of the fish retina: a [3H]dopamine release study with isolated fractions.

Inner retinal cells including dopamine (DA) cells were isolated and fractionated from the carp (Cyprinus carpio) retina by an enzyme cell dissociation and metrizamide gradient centrifugation method. When gamma-aminobutyric acid (GABA) antagonists (bicuculline and picrotoxin) were added into the perfusate over such a cell fraction, they stimulated the release of [3H]DA which had been preloaded in the cell fraction. The action of GABA antagonists was dose and Ca2+ dependent.

Immunohistochemical study of folliculo-stellate cells in human pituitary adenomas.

Folliculo-stellate (FS) cells were studied in 102 human pituitary adenomas by immunohistochemical techniques using antibodies to S-100 protein and intermediate filaments protein. In most pituitary adenomas there were few S-100-positive cells, in contrast, numerous FS cells were found in four of the 54 cases of non-functioning adenomas. Among glial fibrillary acidic protein (GFAP), keratin and vimentin, FS cells showed greatest affinity to vimentin.

Reconstruction of surgical skull defects with hydroxylapatite ceramic buttons and granules.

This paper is to report a new method of reconstructing surgical skull defects with hydroxylapatite ceramics. The latter consist of Ca10(PO4)6(OH)2 which has a biological affinity with mammalian bone minerals. The author has designed two cranioplastic materials using hydroxylapatite ceramics: apatite buttons for burr hole skull defects and apatite granules for linear skull defects.