Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0851184 (thinning)
 11,252 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Previous studies have shown that the concentrations of 3', 5' cyclic adenosine monophosphate (cAMP) and 3', 5' cyclic guanosine monophosphate (cGMP) in cerebrospinal fluid (CSF), brain, or both, are increased by melanotropic peptides and catechol amines, and by cholinergic agents. The present study measured the concentrations of cAMP, cGMP, and melanotropic activity in the CSF of normal patients and in 136 subjects with various neurologic diseases. In normal lumbar CSF, concentrations (ave +/- SD) were: cAMP, 21 +/- 8 mM; cGMP, 2.4 +/- 0.5 mM; melanotropic activity, 17 +/- 6 units/100 ml. Concentrations of cAMP, cGMP, and melanotropic activity did not differ significantly (P is less than .05) from normal in the following categories of adult and pediatric patients: back pain due to vertigo of unknown cause; cerebral atrophy; cerebral vascular disease; and brain tumor subdural hematoma not causing increased ventricular pressure. Nine children with retarded psychomotor development caused by diffuse brain disease (infection, trauma, hemorrhage, degenerative process, long-standing hydrocephalus with thinning of the cerebral mantle) had subnormal levels of cAMP and melanotropic activity. These two variables were significantly correlated in the entire series of CSF samples (r=+0.55, P is less than .005). cGMP was elevated in the ventricular fluid of adult and pediatric patients when the ventricular pressure was abnormally elevated. The nucleotide's level rose as high as 50 X normal when ventricular pressure exceeded 300 mm H2O. The concentration of ventricular cGMP was proportional to that of ventricular pressure (r=+0.76, P is less than .005). The correlation was similar regardless of the type of hydrocephalus (congenital or acquired, communicating or obstructive), the age of the patient, or the nature of the underlying disease.
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PMID:Observations on the cyclic nucleotide concentrations in human cerebrospinal fluid. 18 45

The morphological mechanism of the reconstitution of shunted mantle was studied histopathologically in 22 kaolin-treated hydrocephalic puppies. A remarkable attenuation of cerebral mantle to less than 1 cm in thickness was seen on computerized tomography (CT) scans of four animals sacrificed 1 to 2 months after kaolin treatment (preshunt group). Ventricular shunting resulted in successful recovery of the mantle on repeated CT scans obtained 1 to 2 months after shunting in seven animals (postshunt group). In the remaining 11 animals the cerebral mantle, which had been reduced to 4 mm in thickness prior to shunting, failed to recover even 2 months after the procedure (shunt-refractory group). On gross inspection, the preshunt specimens showed marked thinning of the white matter, with the cortical ribbon well preserved, while the postshunt specimens consisted predominantly of thickened white matter. Histopathological examination of the attenuated white matter of the preshunt specimens showed decreased nerve-fiber density, myelin destruction with myelin regeneration and/or repair of myelin sheaths, and reactive astrocytosis, which were prominent especially in the periventricular white matter. The main findings in the reconstituted white matter of the postshunt specimens were extensive myelin regeneration of residual axons and remarkable astroglial proliferation with mesenchymal reaction, particularly at capillaries. No clear evidence of increased numbers of nerve fibers or axonal regeneration was observed. The shunt-refractory specimens showed remarkable attenuation of cortex, in which reduced numbers of neurons and loss of cortical lamination were noted, with vestigial white matter. The results indicate that astroglial proliferation with mesenchymal reaction and myelin regeneration contribute to the reconstitution of the cerebral mantle volume following ventricular shunting in this model. It is suggested that the critical factor for mantle reconstitution in chronic hydrocephalus is whether cortex is preserved.
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PMID:Reconstitution of shunted mantle in experimental hydrocephalus. 156 46

Hydrocephalus is classified into communicating, if cerebrospinal fluid (CSF) can flow freely from the ventricle to the subarachnoid space, and into non-communicating, if it cannot. The cause of hydrocephalus is diverse, either congenital or acquired conditions causing obstruction to the flow of CSF. The location of the lesion is more important than the size or nature of the lesion. We describe an unusual case of congenital communicating hydrocephalus associated with multiple malformations of midline telencephalic structures. This was a premature male baby of 30 weeks gestational age. The pregnancy was terminated after revealing a hydrocephalus by ultrasonography. The cerebral hemispheres showed marked thinning of parenchyme with dilated lateral ventricles, communication of lateral and third ventricles with dilated foramina of Monro, absence of the septum pellucidum, and hypoplasia or focal agenesis of posterior portion of corpus callosum with dorsal dilation of the third ventricle. The right fornix appeared as a single thick midline cord in its approximately normal position and the hippocampi were poorly developed, especially in the left side. The left fornix was rudimentary.
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PMID:Congenital hydrocephalus associated with anomalies of midline telencephalic structures. A case report. 179 89

Aicardi syndrome is characterized by infantile spasms, agenesis of the corpus callosum, severe mental retardation, and a characteristic chorioretinopathy with lacunar defects. The authors report on a 2-year-old girl with congenital hydrocephaly who was found unresponsive by the baby-sitter and died shortly thereafter. At autopsy, the histopathologic findings, which were confined to the brain and eyes, were found highly characteristic of AIC. The main abnormalities included agenesis of the corpus callosum, micropolygyria, bilateral papillomas of choroid plexi, bilateral microphthalmia, bilateral hypoplasia of the optic nerves, bilateral colobomas of the juxtapapillaris choroid and optic disc, bilateral total retinal detachment with dysplastic rosettes and chorioretinal lacunae with focal thinning, and atrophy of the retinal pigment epithelium and choroid. A detailed histopathologic study of the ocular findings and the brain anomalies is presented. The results of scanning electron microscopy of the chorioretinal lacunae demonstrated peculiar papillary proliferations of the retinal pigment epithelium in both eyes.
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PMID:Aicardi syndrome. A clinicopathologic case report including electron microscopic observations. 180 Sep 34

Rats from the H-Tx strain develop hydrocephalus through a developmental obstruction of the cerebral aqueduct. The progressive ventriculomegally is accompanied by thinning of the cerebral cortex which is already present 10 days after birth. However, a previous study found that the CSF pressure was not significantly raised until 21 days after birth. New experiments have now been performed over a 90 min. period using control and hydrocephalic 10-day-old rats under light pentobarbitone anaesthesia, in order to study the level, time-course and morphology of the resting intraventricular pressure. The mean pressure and its fluctuations were calculated for each minute. Control rats had a mean pressure of 19.3 +/- 1.23 (SEM) mm H2O (n = 9, range: 13.6-24.7) and in hydrocephalic rats, pressure was significantly higher at 23.5 +/- 1.13 mm H2O (n = 9, range: 18.1-28.3). There was no consistent trend with time and no significant difference between groups in pressure fluctuations, but at least two of the hydrocephalic rats showed episodic waves similar to "B"-waves in humans.
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PMID:Cerebrospinal fluid pressure in 10-day-old rats with congenital hydrocephalus. 180 75

A 3-year-old, castrated male Pekingese was examined 2 days after automobile-induced trauma. Multiple pelvic injuries and visual deficits in the right eye were identified. During a subsequent postmortem examination, multiple pelvic fractures were confirmed; however, there was no evidence of head injury. Both globes were bilaterally symmetrical and grossly normal. The intraorbital and intracranial portions of the right optic nerve were threadlike and rudimentary in appearance, while the left optic nerve was grossly normal. Moderate dilatation of the left lateral ventricle was noted. Microscopically the right optic nerve and left nerve tract contained few identifiable nerve fibers. The right optic disc was depressed, and there was thinning of the optic nerve fiber and ganglion cell layers of the retina. No microscopic abnormalities were evident in the left optic nerve, optic disc, retina and right optic tract. The histologic changes in the right eye are consistent with optic nerve hypoplasia. The relationship between the optic nerve/optic tract lesions and the hydrocephalus is unknown.
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PMID:Unilateral optic nerve hypoplasia and hydrocephalus in a Pekingese. 187 43

We studied six cases of unilateral hydrocephalus detected prenatally to analyze the sonographic features of the abnormality and to determine the cause and clinical outcome. In all cases, third-trimester sonograms showed marked unilateral lateral ventriculomegaly (mean atrial width, 4.4 cm) and normal contralateral lateral, third, and fourth ventricles. Five of the six cases had marked thinning of the cortical mantle on the affected side and shift of midline structures to the contralateral side. The causes of unilateral hydrocephalus were agenesis or stenosis of the foramen of Monro in three cases, transient obstruction of the foramen in one fetus with an intraventricular hematoma, underlying brain dysplasia in one fetus with a variant of holoprosencephaly, and undetermined in one case. All six neonates had placement of a ventriculoperitoneal shunt catheter; four of these have had normal cognitive development at follow-up. The remaining two infants have moderate to severe developmental impairment. Unilateral hydrocephalus is a rare anomaly that can be recognized by prenatal sonography. Even though unilateral ventriculomegaly may be marked, early diagnosis and treatment may result in a favorable clinical outcome.
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PMID:Unilateral hydrocephalus: prenatal sonographic diagnosis. 189 14

The clinical features of patients with hydrocephalus include generalized reductions in coordinated motor and cognitive functions. Although some group similarities have been noted, the outward manifestations of this dysfunction vary in degree and character, with some subjects revealing no overt signs of the underlying hydrocephalus. A retrospective review of subjects with MR criteria of hydrocephalus was undertaken to reevaluate the specific imaging correlates of the signs and symptoms associated with this pathologic process. Forty adults with hydrocephalus on MR evaluation were carefully scrutinized in an effort to elucidate specific clinicoradiologic patterns of abnormality. Spin-echo MR techniques were used with T1 and/or T2 weighting in three orthogonal planes. MR criteria of hydrocephalus encompassed dilated lateral ventricles to include the temporal horns, a pronounced upward elevation of the corpus callosum, and an outward expansion of the cerebral hemispheres at the expense of the subarachnoid space overlying the convexities. The significant related morphologic change on MR that has not been previously described in hydrocephalus was a localized dorsal flattening and thinning of the posterior body of the corpus callosum. Importantly, all but three of the 24 patients with this phenomenon manifested varying combinations of imbalance, gait disturbance, incontinence, short-term memory deficits, and global dementia. In the presence of hydrocephalus, but in the absence of this specific callosal configuration, only one of the remaining 16 subjects revealed symptoms that might suggest the presence of hydrocephalus (i.e., profound dementia). The structure responsible for this focal callosal flattening and thinning in hydrocephalus is the rigid free surface of the falx cerebri as it impinges on the caudal extent of the upwardly expanding corpus callosum and supracallosal hippocampal formation. This mechanical insult hypothetically causes variable axonal dysfunction, ranging from decreased to increased neurophysiologic activity. In summary, it is postulated that callosal impingement represents a dynamic partial hemispheric disconnection and accounts, in part, for the complex clinical state associated with hydrocephalus.
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PMID:Clinical manifestations of hydrocephalus caused by impingement of the corpus callosum on the falx: an MR study in 40 patients. 190 38

Hydrocephalus in the H-Tx rat first develops in late gestation and causes death at 4-7 weeks. The effect of hydrocephalus on overall cortical dimensions and on five specific regions (frontal, sensory-motor, parietal, auditory and visual) has been studied by quantitative light microscopy at 10 and 30 days after birth. The lateral ventricle volumes in hydrocephalic rats were about 40 x larger than controls and increased fourfold between 10 and 30 days. Cortical volume was reduced by a small amount at 10 days but was larger in hydrocephalics at 30 days. Thinning of the cortical mantle was severe with disruption of the laminar structure, particularly in the auditory and visual regions, where it was already present at 10 days. The density of cortical cells (neurones and glia) was not altered in hydrocephalics at 10 days but was reduced in all regions at 30 days. Estimates of total cell number suggest that the lower density was not associated with an overall loss of cells. Capillary numerical density was not affected by the hydrocephalus at 10 days after birth but by 30 days it was significantly lower, particularly in the worst-affected posterior regions. The results show that the cerebral cortex is severely distorted and that in advanced hydrocephalus, although overall cell number is not affected, both cell density and capillary density are lower by up to 30%.
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PMID:The cerebral cortex in congenital hydrocephalus in the H-Tx rat: a quantitative light microscopy study. 192 78

The typical CT findings of Lhermitte-Duclos disease (dysplastic gangliocytoma of the cerebellum) are a hypodense nonenhancing unilateral posterior fossa mass, with or without adjacent occipital thinning, hydrocephalus, and calcification. Magnetic resonance (MR) has been found to be very helpful, and superior to CT, in delineating the margins of the lesion for determining the extent of surgical resection. Since recurrence is known, MR is important in the follow-up of these patients. To our knowledge this is the first reported case that included MR examination with administration of gadolinium. There was no enhancement of the lesion, consistent with previous reports of no contrast enhancement on CT.
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PMID:Lhermitte-Duclos disease: CT and MR findings. 222 80


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