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At least 1,441 records · Page 80Linked to original sources
PubMed1989

[Determination of particulate matter in small volume antibiotic injections].

Amounts of particulate matter present in 17 small volume antibiotic injections marketed in Japan were determined using light obscuration particle analyzer (HIAC). The vial volume range of each batch of product was 7-20 ml, and each vial contained 1 g as antibiotic potency. In 4 products, contents of particles between 2.5 and 10 microns in diameter were counted 2,000-7,000 per vial, and particles in other products were counted less than 2,000 per vial. Numbers of particles greater than or equal to 10 microns in diameter were much less than the USP XXI criteria for particulate matter in small volume injections. The product of the highest counts for particles between 10 and 25 microns in diameter showed counts amounted to 0.13% of the USP XXI criteria. In the 25-50 microns particulate diameter range, particulate matters were detected only in 2 products, and they were less than 0.2% of the USP XXI criteria. Particles over 50 microns in diameter were not detected in any products. These results showed that 17 small volume antibiotic injections marketed in Japan had good qualities regarding contents of particulate matter.

Anti-Bacterial Agents↗
PubMedDate not supplied

[Heterotopic gray matter: an infrequent cause of epilepsy].

Heterotopia of gray matter is a developmental malformation in which ectopic cortex is found in the white matter of the brain. A case of a 27-year-old woman with generalized convulsions is reported, including the results of cerebral computed tomography and magnetic resonance imaging. In this patient, nodular masses of gray matter were present in the periventricular region. We emphasize that magnetic resonance imaging is the current method of choice for diagnosing heterotopic gray matter.

Adult↗
PubMed1987

[Synaptogenesis and axon collaterals coming from the white matter in the upper cervical cord of the 10 day (stage 36) chick embryo--Golgi and electron microscopic studies].

Our previous study with 3H-thymidine autoradiography showed that neurons of the zona spongiosa, the nucleus proprius of the dorsal horn, the zona intermedia and the ventralhorn differentiated earlier than those of the substantia gelatinosa and the neck and the base of the dorsal horn, and that neurons of the substantia gelatinosa which were the last to differentiate reached their final position at stage 36 (Fig. 1). In the upper cervical cord of chick embryos at stage 36 when all spinal neurons finished cell migration and the cytoarchitecture similar to that of the cat spinal cord (Rexed, 1952) could be recognized (cf. Figs. 1, 3B), we studied the distribution of synapses by the electron microphotomontage (Fig. 3 A) and the morphology of axon collaterals coming from the white matter by the Golgi method (Fig. 4), in order to examine i) which spinal neurons have synaptic contacts at this stage and ii) what part of the axon collateral makes synaptic contacts. In the white matter, synapses were numerous around the gray matter and they were few in the peripheral part along the external surface of the cord. The paucity of synapses in the peripheral part was explained by a finding that dendrites reaching the external surface of the cord were few in number at this stage (cf. Fig. 3 C). In the gray matter, synapses were more numerous and denser in the zona intermedia and the ventral horn than in the dorsal horn.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1985

[A case of simple form of sudanophilic leukodystrophy of a child which showed a marked loss of cerebral white matter and fatty liver].

A sporadic case of sudanophilic leukodystrophy of the simple form (Peiffer) was reported. The patient was three-year-old girl who had suffered from progressive developmental retardation and neurological disorders such as ataxia, cortical blindness and spastic paralysis of the extremities for eighteen months after she had showed normal development till one and a half years old and died from respiratory insufficiency. On admission, computerized tomogram scan demonstrated diffuse low density lesions of the cerebral white matter extending subsequently to the subcortical white matter. Examination of cerebrospinal fluid revealed only slight increase of protein. Lysosomal enzyme activities such as arylsulfatase and beta-galactosidase in the white blood cells were normal except for distinctly low activity of a-mannosidase without any clinical symptoms suggesting a-mannosidase deficiency. Amino acids in blood were normal. The brain weighed 900 gm. On the coronal sections most part of the cerebral white matter was so strongly degenerated and disappeared that the lateral ventricular structure was not discernible. Histologically, a diffuse and symmetrical demylination, loss of axons including U fibers and moderate gliosis were observed in the residual white matter in the cerebrum and pons. There was no inflammatory cells and metachromatic substances. Large amount of sudanophilic droplets showing polarizing cross and needle like crystals were found in the intra- and/or extracytoplasm of macrophages. Demyelinated lesions with little tissue reaction were also found in the cerebellum, medulla oblongata and in pyramidal tracts through midbrain to cervical spinal cord. There were slight loss of neurons and moderate astrocytosis in the cerebral cortex and basal ganglia. There were no Rosenthal fibers and no sparing of islets of myelin.(ABSTRACT TRUNCATED AT 250 WORDS)

Brain↗
PubMedDate not supplied

Periventricular white-matter cysts in a murine model of gram-negative ventriculitis.

Hydrocephalic patients with shunt infections frequently develop multiple cerebrospinal-fluid-density cysts that cause midline shift and life-threatening intracranial hypertension and respond poorly, if at all, to shunt diversion of cerebrospinal fluid. These cysts have been considered to represent multiloculation of the ventricular system by ependymal adhesions and veils resulting from ventriculitis. Studies using an experimental model of E. coli meningitis/ventriculitis in the hy-3 mouse suggest these cysts: (1) develop by the coalescence of lakes of white-matter edema, (2) grow to large size entirely within the periventricular white matter, and (3) cause pseudoloculation of the ventricle by compression from without. The so-called intraventricular septa or "veils" are the ependyma displaced inward by subependymal cysts or sheets of residual pericystic white matter. This finding permits better interpretation of computed tomographic images depicting persistent enlargement of the so-called multiloculations despite functioning ventricular shunt catheters, the multiplicity of cysts, and the white-matter location of these cysts.

Animals↗
PubMedDate not supplied

Analysis of commercial pollen extracts by enzyme determination. II. Determination of the contamination of pollen extracts with plant matter.

The contamination of pollen extracts by plant matter was studied by means of enzymes. Beta-glucosidase was detected only in flowers and leaves by using the Api-Zym System. 29 pollen extracts were prepared after microscopic control. Among these 23 did not contain any plant matter and no beta-glucosidase activity could be detected. In contrast, 6 extracts were contaminated with plant matter and in every case beta-glucosidase activity was found 34 commercial pollen extracts completed the study. beta-glucosidase activity was present in 8 of them. It may be postulated that glucosidase activity detected using 2- naphthyl - beta D-glucopyranoside as a substrate, can be correlated with the presence of plant matter from the raw material from which the extract was prepared. This contamination may be important to determine since some additional sensitization may occur with such extracts during immunotherapy.

Drug Contamination↗
PubMedDate not supplied

Parenchymal CT correlates of senile dementia (Alzheimer disease): loss of gray-white matter discriminability.

Neuropathologic studies have defined gross anatomic (structural) as well as histologic (parenchymal) changes of senile dementia (Alzheimer disease). This investigation suggests that loss of gray-white matter discriminability by computed tomography (CT) is related to cognitive impairment in this disease. Discriminability is defined as the relative ease of visual differentiation between gray and white tissues. Twenty-six elderly patients with dementia were subjected to extensive psychometric evaluation, a medical and neurologic examination, and CT scanning. Gray and white matter changes were assessed by subjectively evaluating three brain levels, the basal ganglia, the centrum semiovale, and the high convexity, on a five point scale. Quantitated gray and white matter scores were also obtained by sampling CT attenuation values. In addition, CT structural changes were evaluated by previously reported methods. there were significant correlations (P less than 0.05) between the subjectively assessed loss of gray-white matter discriminability at all brain levels and the measures of cognitive decline. At the high convexity level 91% of cognitive measures correlated with loss of gray-white discriminability. In the same patient group no gray-white discriminability correlation with age was demonstrated suggesting that gray-white discriminability does not simply change with age.

Aged↗
PubMed1982

Different volume changes of cerebral cortex and white matter during histological preparation.

In quantitative neuroanatomy and neuropathology, large neuronal systems are frequently analyzed on the basis of small tissue blocks thus assuming that the volume changes of the various compartments of the tissue block can be corrected by an overall factor. 228 blocks of cerebral cortex and white matter of the frontal lobe, thalamus, and striatum were prepared from 13 human brains and embedded in paraffin. The mean shrinkage in the paraffin sections was found to be 51% for the cerebral cortex and 42% for the white matter. Therefore, an overall correction factor tissue blocks both with cerebral cortex and white matter results in an underestimation of cerebral cortex and an overestimation of white matter.

Adult↗
PubMed1981

Effects of particulate matter from carbenicillin disodium solution on human macrophages in vitro.

The effects of particulate matter from reconstituted carbenicillin disodium on cultures of human macrophages was studied. Particulate matter from commercially available carbenicillin disodium was collected on 0.1 micrometer membrane filters. Monocytes/macrophages obtained from human peripheral blood were cultivated on the particle bearing surface of the filter in culture medium. The cells were incubated in tissue cultures dishes at a concentration of 2 x 10(6) cells per dish. Experimental and control cultures were observed over six days for changes in morphology, cell membrane integrity, phagocytic capacity, and viability. Exposure of the cells to the particles was not cytotoxic. Cell membrane integrity remained intact as shown by no increase of LDH in the extracellular fluid. The phagocytic capacity of the cell system was not impaired as assessed by observing the intracellular levels of glucose-6-phosphate dehydrogenase. Morphological changes as monitored by phase contrast and bright field microscopy were consistent with increased cellular activity. Particulate matter from carbenicillin disodium may not be toxic to human macrophages in vitro for up to six days. At the concentrations used in this study, particulate matter did not lower the phagocytic capacity of human macrophages in vitro.

Carbenicillin↗
PubMed1995

Methanol intoxication with putaminal and white matter necrosis: MR and CT findings.

We report a case of methanol intoxication in which the initial CT scans appeared normal. MR at 4 days showed the typical putaminal lesions of methanol intoxication and, in addition, peripheral white matter lesions that spared a thin rim of subcortical white matter. A CT scan at 17 days showed the putaminal and white matter lesions. The white matter lesions correspond well to lesions previously described in pathologic specimens.

Adult↗
PubMed1994

Systemic lupus erythematosus presenting with diffuse low density lesions in the cerebral white matter on computed axial tomography scans: its implication in the pathogenesis of diffuse central nervous system lupus.

We describe a patient with systemic lupus erythematosus (SLE) with severe organic brain syndrome, who showed diffuse low density areas in the cerebral white matter on computed axial tomography (CAT) scans. A 43-year-old woman with SLE showed disturbances in various intellectual functions, followed by the development of consciousness disturbances and urinary incontinence. CAT scans, single photon emission computed tomography (SPECT) and cerebrospinal fluid (CSF) interleukin 6 (IL-6) were serially examined during the clinical course before and after treatment with high doses of prednisolone. CSF IL-6 activity paralleled the central nervous system (CNS) disease activity most consistently. By contrast, the diffuse low density areas in cerebral white matter on CAT scans as well as the decreased blood flow in the cerebral cortices on SPECT persisted long after the improvement of the CNS manifestations. Magnetic resonance imaging (MRI) scans also revealed the diffuse areas of increased signal intensity in the subcortical white matter on T2 weighted images. The diffuse lesions in the cerebral white matter are considered to reflect the edema as well as other irreversible changes that have resulted from the disturbed cerebral circulation presumably due to the diffuse microangiopathies in the cerebral cortices and not to be necessarily correlated with the CNS disease activities. Moreover, it is suggested that the inflammatory process evidenced by the elevation of CSF cytokines in addition to the disturbed circulation in the cerebral cortices might play an important role in the pathogenesis of CNS lupus in our patient.

Adult↗
PubMed1994

[MRI of paraventricular white matter lesions in amyotrophic lateral sclerosis--analysis by diffusion-weighted images].

Magnetic resonance images in some cases of amyotrophic lateral sclerosis (ALS) revealed abnormal signals in both the paraventricular white matter and in the posterior limbs of the internal capsule. We examined T2- and diffusion-weighted MR images of these lesions in 18 cases of ALS. There were symmetrical high-signal areas in the posterior limbs of the internal capsule in all of the cases. The high-signal areas in the internal capsule corresponded to the pyramidal tracts in the anatomical atlas by Talairach. In 5 of the cases of ALS, T2- weighted MR images showed discrete paraventricular white matter lesions as well. The mean age of the ALS patients with paraventricular white matter lesions was higher than that of the ALS patients without such lesions. Proton densities calculated from the conventional MR images were higher in both the capsular and paraventricular lesions. The diffusion coefficients perpendicular to the pyramidal tract in the internal capsula lesions were within the normal range, where as the diffusion coefficients in the paraventricular lesions were increased in all directions. Thus, diffusion anisotropy was lost in the paraventricular lesions. These findings are similar to those observed in the white matter lesions of cerebro-vascular origin. As a result, the pathology of the paraventricular lesions in ALS was confirmed to be different from that of the internal capsular lesions.

Aged↗
PubMed1975

[Changes in the dry matter and various minerals in the sow endometrium during the sexual cycle].

Analyses were performed in 16 praepubertal and 85 sexually mature gilts of the Bohemian Large White breed. The content of dry matter in the endometrium of praepubertal gilts was 15.511%, on an average, and in sexually mature sows 11.968%, on an average, in the follicular phase, and 14.326% in the luteal phase. The differences are statistically highly significant (P less than 0.01). Considerable differences (mostly highly significant) were found also in the contents of calcium, phosphorus, magnesium, sodium, potassium, and chlorine in the dry matter of endometrium in praepubertal and sexually mature sows; however, these differences were less frequently dependent on individual stages of the sexual cycle. The highest content of calcium (1.112 mg g(-1)), phosphorus (8.357 mg g(-1)), and magnesium (0.720 mg g(-1)) in dry matter was found in gilts in the oestral phase, and the lowest in late or early metestrus (Ca = 0.625 mg g(-1), P = 0.6369 mg g(-1), Mg = 0.498 mg g(-1). Sodium showed the highest values in proestrus (23.359 mg g(-1)), and potassium in oestrus (13.012 mg g(-1)); their lowest values were recorded in late metestrus (Na = = 17.742 mg g(-1)) and in proestrus (K = 10.141 mg g(-1)). The content of these elements in endometrium dry matter was also much lower in praepubertal gilts than in sexually mature sows (with the exception of phosphorus); the difference was always highly significant.

Animals↗
PubMedDate not supplied

[Lipids from gray and white rat brain matter in autolysis].

A decrease in relative content of phospholipids and cholesterol simultaneously with increase in cholesterol esters and free fatty acids were detected in tissues of rat brain gray and white matters during autolysis at 37 degrees within 6-7 min, 1, 4 and 24 hrs; the most distinct alterations were observed in lipids of the gray matter especially at early (6-7 min) and late (24 hrs) stages of autolysis. In the gray matter, relative content of all the lipid fractions studied was restored to initial level within 4 hrs of incubation. In the white matter, during autolysis the content of cholesterol varied, the content of phospholipids was only slightly increased, while the level of free fatty acids was increased only at 24 hrs of incubation with synchronous decrease in content of triacylglycerols, cholesterol and, partially, phospholipids. These experimental data are of importance in resuscitation. Both common and dissimilar mechanisms of these lipid alterations are discussed. Not only the complex of hydrolase reactions but also that of transacylase and other reactions, involved in the degradation and biotransformation of brain lipids in autolysis, were noted.

Animals↗
PubMed1995

[Intellectual impairment and brain MRI findings in myotonic dystrophy: with a special reference to hippocampal atrophy and white matter lesions].

We performed a correlative study between intellectual impairment, CTG repeat expansion and magnetic resonance imaging (MRI) abnormalities, including hippocampal atrophy, white matter lesions and ventricular dilatation in 15 patients with myotonic dystrophy (MD). They included 4 males and 11 females aged from 20 to 66 years, averaging 43 years of age and 15 years of duration of illness. Nine patients had intellectual impairment (WAIS-R<80). Negative correlations were found between full scale IQ (FSIQ), duration of illness (p<0.05) and CTG repeat expansion (p<0.05). Compared with normal controls, the patients with MD showed a significant reduction in size of the hippocampal head (p<0.01), which was positively correlated to FSIQ, verbal IQ and performance IQ levels (p<0.05). Ten patients had white matter lesions. Severer white matter lesions tended to be recognized in patients with longer duration of illness and with decreased FSIQ level. These results suggest that hippocampal atrophy and white matter lesions are related to intellectual impairment in patients with MD.

Adolescent↗
PubMed1996

Pattern of tau-1 and ubiquitin immunoreactivity in the white matter of temporal lobe in senile and with Alzheimer's disease brains.

Immunostaining pattern of the temporal white matter with anti-tau-1 and anti-ubiquitin was different in examined cases of Alzheimer's disease (AD) and normal aging. Tau-1 immunoreactivity was observed in the white matter of all AD brains, in loosely dispersed neuropil threads (NT), a few neurofibrillary tangles (NFT) and scattered glial cells, whereas in majority of senile brains the white matter was immunonegative. Ubiquitin immunoreactivity characterized by dot-like structures, evenly distributed throughout the white matter, was observed in all cases examined being more prominent in AD than in senile brains. The dot-like structures were unrelated to tau-1 immunostaining pattern, as neither NT and NFT nor glial cells were ubiquitin labeled. It was concluded, that different immunostaining with both antibodies used reflects variable pathological changes identified mostly in nerve fibers. There are neurofibrillary changes manifested by tau-1 labeled NT. However, they differed from cortical NT by lack of ubiquitin immunostaining. Non-filamentous ubiquitin-positive depots represent presumably nonspecific nerve fiber changes related to various pathological events, including AD and aging process.

Aged↗
PubMed1996

Schwann cell-neuron relationships in spinal cord gray matter.

Schwann cells develop within the ventral gray matter following exposure of lumbosacral spinal cords to x-rays in early postnatal rats. These ventral gray matter Schwann cell aggregates occurred in about 40% of the animals 8 or more weeks following irradiation. Light microscopically these cells appeared to be apposed to somata of large motor neurons, raising a question regarding the fate of axo-somatic synapses. This study focused on neuron-Schwann cell relationships and demonstrated ultrastructurally that the intraspinal Schwann cells established a variety of relationships with the neuronal somata and primary dendrites. These relationships ranged from direct contact without an intervening basal lamina to the presence of synaptic contacts intervening between neuron and Schwann cell basal lamina. Occasionally, the Schwann cells occupied an intermediate position between neurons and blood vessels, suggesting functions similar to those carried out by astrocytes. In these instances, as in all cases of Schwann cell-blood vessel contact, the vessels lacked their normal investiture by astrocytes. Light microscopic evaluation of synaptophysin-immunostained sections revealed decreased immunoreactivity in neuropil occupied by the Schwann cells but confirmed the presence of synapses on neuronal somata. Possible mechanisms underlying Schwann cell induction in the ventral gray matter are discussed. An understanding of the interactions between Schwann cells and the cellular constituents of the gray matter is important in light of attempts to enhance repair in the central nervous system by transplanting Schwann cells into that environment.

Animals↗
PubMed1997

Megalencephalic leukoencephalopathy: a further case of a new neurodegenerative white matter disease.

The case is presented of a 4.5-year-old boy with cystic megalencephalic leukoencephalopathy who met the diagnostic criteria of a recently described neurodegenerative white matter disorder, i.e. leukoencephalopathy with swelling and a discrepantly mild clinical course (van der Knaap 1995). He demonstrated an extremely mild and slowly progressive clinical course with near normal psychomotor development, particularly of mental functions, which contrasted with somewhat disturbed gross and fine motor skills. Repeated CT and MRI scanning showed extensive hemispheral cerebral white matter changes and demonstrated predominant frontal involvement of the periventricular and subcortical white matter. MRI was more sensitive in the detection of preserved structures, i.e. occipital subcortical and central white matter, as well as in the visualisation of swelling and cystic lesions in the tip of the temporal lobes, which represent the hallmark of this entity. Thus, MRI is an essential diagnostic tool for this entity.

Child, Preschool↗