[Magnetic resonance tomography. A valuable method in the diagnosis of central nervous system diseases in children].
Explore the source record for details and available documents.
Adolescent↗
Biomedical subjects
K Bergström
Publications and source records attributed to K Bergström.
Isoamylase levels in bone marrow transplant patients are affected by total body irradiation and not by graft-versus-host disease.
The mean total serum amylase levels in patients was 3.2 +/- 0.5 mukat/l (+/-SE) before total body irradiation (TBI) prior to bone marrow transplantation of which 50% was due to pancreatic isoamylase and 50% salivary isoamylase. Total serum amylase increased to a maximum of 100.3 +/- 12.3 mukat/l on the first day after TBI and most of this increase was due to an increase in salivary isoamylase (90.0 +/- 12.1 mukat/l). In association with this, all patients had clinical symptoms of parotitis. An increase in pancreatic isoamylase was found in 27% of the patients; however, none of them had clinical symptoms of pancreatitis. Serum amylase levels returned to normal within 5 days after TBI but then decreased to subnormal values, remaining below the normal range for 3 weeks. Pancreatic isoamylase returned to pre-irradiation levels 1.5 months after TBI, while salivary isoamylase remained low for the rest of the observation time. TBI of 7.5 Gy at 26 cGy/min gave significantly lower salivary amylase at 2 days after TBI compared with 10 Gy at 4 cGy/min: 32 +/- 4 versus 76 +/- 13 mukat/l (P less than 0.05). At 2.5 and 6 months after TBI significantly higher total amylase levels were recorded for patients treated with 7.5 Gy of TBI compared with 10 Gy: 2.5 +/- 0.4 and 2.7 +/- 0.3 versus 2.0 +/- 0.5 and 0.8 +/- 0.3 mukat/l, respectively (P less than 0.01, P less than 0.05, respectively). Acute or chronic GVHD did not affect acinar cells in this investigation.
Adolescent↗
Evaluation of customers' complaints about sunscreen cosmetics sold by the Swedish pharmaceutical company.
Sweden's pharmacies hold more than a 1/3 of the country's market for sunscreen cosmetics (sunscreens). Customers complaining of skin problems associated with the use of sunscreens obtained from the pharmacies were offered dermatological investigation and tests with standard allergens and sunscreens. 27 of 58 complaining customers were fully investigated, and another 8 partly tested. 2 disease entities, a burning sensation and erythema for one or a few days, and dermatitis with scaling lasting for up to 3 weeks, were about equally common. Contact or photocontact allergy to 2-hydroxy-4-methoxybenzophenone caused severe contact dermatitis in 3 individuals.
Benzophenones↗
Acute peripheral facial palsy simulating Bell's palsy in a case of probable multiple sclerosis with a clinically correlated transient pontine lesion on magnetic resonance imaging.
A transient pontine lesion was demonstrated in a young adult male who had a complete acute peripheral facial nerve palsy due probably to multiple sclerosis. In the acute stage of the palsy. T2-weighted magnetic resonance imaging (MRI) revealed a high signal intensity in the ipsilateral pons in the region of the nucleus and pontine part of the facial nerve. The patient recovered completely 5 weeks after the onset of the palsy, and at this stage, the lesion in the brainstem was no longer demonstrable on MRI. The onset and course of the disease resembled the idiopathic form of facial palsy (Bell's palsy): the present findings along with recent MRI and topodiagnostic studies may indicate that in some cases of Bell's palsy the primary lesion is located centrally. By improved MRI techniques and intravenous contrast agents it may be possible to visualize and follow the disease process and ascertain more of the pathogenesis of Bell's palsy.
Acute Disease↗
Deposition and gastrointestinal transit of conventional sucralfate tablets.
Sucralfate was labelled with 99mTc by the stannous reduction method. Tablets were compressed using 1 g of radioactive sucralfate and suitable additives. On the first test day, five fully informed healthy volunteers were given one radioactive tablet of sucralfate each, following 10 h fasting. On the second test day, the sucralfate tablet was given after a standard meal. The gastrointestinal transit of the 99mTc-labelled sucralfate was evaluated using gamma camera technique. The labelling of sucralfate with 99mTc by the stannous reduction method enables the deposition and the transition of sucralfate in the gastrointestinal tract to be monitored. The tablets disintegrated almost immediately after administration and the released sucralfate distributed homogenously over the entire stomach area, in both fasted and fed subjects. Transit from the stomach into the intestine was noted already 10 min after administration in fasted subjects, whereas the gastric emptying of sucralfate was markedly delayed in fed subjects. To achieve a wider and more homogenous distribution in the GI-tract, sucralfate tablets should be taken before eating.
Adult↗
Comparison of MR imaging and CT in pituitary macroadenomas.
The findings on mid-field MR imaging and CT were compared retrospectively in 65 patients with pituitary macroadenomas. The evaluation comprised tumour extension and delineation, invasiveness, relationship to adjacent structures, and internal tumoral changes. MR was superior to CT except in the demonstration of bone changes and tumour calcification. The superiority of MR was most pronounced regarding cavernous sinus invasion, tumour relationship to the carotid arteries and optic chiasm, and tumour haemorrhage. Extensive bone changes were visualized with both methods; erosions were often seen only with CT. It is concluded that MR is the preferable method for evaluation of pituitary macroadenomas. CT is useful as a supplementary modality when detailed information on bone anatomy is required, particularly if a transsphenoidal surgical approach is contemplated.
Adenoma↗
Analysis of caprine mycoplasmas and mycoplasma infections in goats using two-dimensional electrophoresis and immunoblotting.
Seven strains of mycoplasma have been characterized by two-dimensional polyacrylamide gel electrophoresis in combination with immunoblotting. The two-dimensional patterns of the strains were compared and similarities and differences are discussed. Hyperimmune rabbit antisera were used in the immunoblotting experiment to study the immunological cross-reactivity between the species. Sera from goats, naturally and experimentally infected with mycoplasma, were also used in the immunoblotting experiment to study the immune responses of the infected animals.
Animals↗
Rebound of ICP after brain compression. An MRI study in dogs.
The rebound of intracranial pressure (ICP) occurring after decompression of an intracranial mass lesion was studied in an epidural balloon compression model. Intracranial morphology and brain tissue water content were assessed with magnetic resonance imaging (MRI). Fast and slow components of the transverse relaxation time (T2) were used as indicators of brain oedema development. During balloon compression a progressive prolongation of both the fast and the slow T2 components took place. Following deflation of the balloon both components increased rapidly, particularly the slow-T2. The MR scans displayed progressive occlusion of the aqueduct, and obliteration of the ambient and pontine cisterns. The changes in morphology and in water content after decompression had largely the same time course as the development of the rebound of ICP. In contrast, no changes in morphology and tissue water content occurred after hydrostatic brain compression achieved by subarachnoid fluid infusion. The findings suggest that the intracranial pressure rebound is caused by cerebral oedema accumulated during and particularly in the recirculation phase after an ischaemic injury of adequate intensity and adequate duration.
Animals↗
Evaluation of syringomyelia and Chiari malformations using ultra-low magnetic resonance imaging.
The accuracy of ultra-low field magnetic resonance imaging (MRI) compared to medium-field MRI in detecting syringomyelia and associated Chiari malformations is examined. In all cases the size of the syrinxes and the type and extent of the Chiari malformations was clearly shown at low-field MRI. The present spatial solution and high sensitivity allows for low-field imagers to localize even minor morphological changes of the spinal cord, brainstem, and cerebellum.
Adolescent↗
Delineation of gliomas with magnetic resonance imaging using Gd-DTPA in comparison with computed tomography and positron emission tomography.
Fourteen patients with cerebral gliomas were investigated by MR imaging using Gd-DTPA (Magnevist), CT with the contrast agent iohexol (Omnipaque) and, as a reference, positron emission tomography (PET) using 11C-L-methionine. Tumour areas with disruption of the blood-brain-barrier (BBB) as seen on MR and CT were compared with areas increased accumulation of methionine in PET. There were 6 patients with high-grade astrocytoma (grade III-IV), 5 with low-grade astrocytoma (grade I-II) and 3 with oligodendroglioma. In 4 high-grade tumours, PET showed a larger tumour or tumour tissue in additional areas, compared with enhancement on MR and CT, while in 2 cases the tumour extension was similar in the three modalities. In the low grade tumour group, the findings on PET differed from those on post-contrast MR or CT in 7 cases. In 3 of these cases, no disruption of the BBB was seen either on MR or on CT. In 2 of our 14 patients CT showed larger enhancement extension than MR and in 2 cases MR was superior to CT in this respect. The enhancement intensity was higher on MR in 4 patients and on CT in 2 patients. No definite difference in the delineation of tumour tissue between the T1 weighted SE sequences was found. The gradient echo sequences FLASH and FISP gave limited information that was less than that provided by the T1 weighted SE sequences. A greater increase in signal intensity in T1 weighted images was usually seen 5 min post-contrast in the high-grade tumours than in the low-grade ones.
Adult↗
Magnetic resonance in Bell's palsy.
The brain and the brain stem were investigated by magnetic resonance (MR) in 19 patients with complete acute peripheral facial palsy, diagnosed as Bell's palsy. Five patients with a median age of 57 years had changes on T2 weighted MR: One patient showed transient signal changes with increased signal intensity in the ipsilateral brain stem. Another patient had persisting abnormal signals both in the brain and the brain stem. Two patients presented regions of high signal intensity in the subcortical cerebral white matter and still another patient had increased signal intensity in the periventricular white matter. MR abnormalities anatomically related to the facial nerve or its nucleus were not demonstrated. The significance of the MR findings is not quite certain but the MR pattern in conjunction with the patient's high median age most likely indicate vascular disease.
Adult↗
[PET--new ways inside the body].
Using positron-emitting short-lived radionuclide tracers, a wide range of substances can now be labelled without their biological properties being affected. Positron emission tomography (PET) enables the distribution and metabolism of the labelled substance to be studied in different organs. By providing quantitative, locational, functional and biochemical information difficult to obtain by other means, PET opens up new possibilities, both diagnostic, pathophysiological and therapeutic, in a broad spectrum of medical practice. The development of the technique is described, with particular reference to its use at Uppsala.
Abdominal Neoplasms↗
Effects of somatostatin on hepatic bile formation.
Somatostatin is a peptide that has anticholeretic properties in the dog. The purpose of the present work was to investigate if somatostatin is an anticholeretic agent in humans also. The effects of intravenous infusion of somatostatin on hepatic bile flow and biliary electrolytes and secretion of biliary lipids were studied in 7 patients with complete biliary drainage who had been operated on for choledocholithiasis. Somatostatin, 250 microgram/h, was found to decrease the hepatic bile secretion by approximately 30%. The peptide also reduced the outputs of bile acids, cholesterol, and phospholipids and the outputs of sodium, potassium, and chloride. The concentrations of the biliary lipids were not significantly changed. Somatostatin inhibited the erythritol clearance in the 2 patients studied by approximately 25%. The present study thus provides evidence that somatostatin inhibits bile formation in humans. It appears as if the reduction in bile production is mainly due to decreased canalicular bile flow. It is possible that this effect of somatostatin is attributable to inhibition of bile acid synthesis or of transport-secretion of bile acids, or both.
Adult↗
Distribution of 11C-labelled morphine and pethidine after spinal administration to Rhesus monkey.
The kinetics of 11C-labelled morphine and pethidine were studied by positron emission tomography (PET) at different levels of the spinal canal (C4, T4, T5, T6, L1 and L6). Studies were performed in the Rhesus monkey after intrathecal and extradural administration of the drugs at the lumbar level (L3-L4 or L4-L5, seven experiments). Radioactivity 100-300 times higher than with even distribution in the body was measured initially near the site of injection for both morphine and pethidine, irrespective of the route of administration. After injection of pethidine, high activity was observed at the L6 and L1 levels, whilst the radioactive uptake was lower at T6 (10-20% of those at lumbar level). Morphine-derived 11C-radioactivity showed more constant levels along the spinal canal, except at C4 where radioactivity was low. In CSF taken from the cervical level the peaks of radioactivity of the two drugs appeared 80-170 min after injection. The importance of different distribution routes was quantified in a pharmacokinetic compartment model, using the above results. The systemic distribution was extensive, irrespective of drug or route of administration. From the site of injection the systemic distribution was at least 60 times larger than the rostral distribution within the spinal canal.
Animals↗
Magnetic resonance imaging in patients with Bell's palsy.
Magnetic resonance imaging of the brain and the brain stem was performed in 18 patients with complete acute peripheral facial palsy and diagnosed as Bell's palsy. In five patients T2 weighted images revealed regions of high signal intensity in the cerebral white matter and/or in the brain stem. The changes indicate that in cases of Bell's palsy the central nervous system may be involved and the disease may be related to microvascular or demyelinating disorder.
Adolescent↗
[Brain death diagnosis and ethics].
Explore the source record for details and available documents.
Brain Death↗
Unilateral MPTP lesion in a rhesus monkey: effects on the striatal dopaminergic system measured in vivo with PET using various novel tracers.
We have produced in one monkey a unilateral lesion of the dopaminergic nigrostriatal pathway by slowly infusing 1-methyl-4-phenyl-1.2.3.6-tetrahydropyridine (MPTP) into the right internal carotid artery, resulting in contralateral hemiparkinsonism. This procedure was combined with a series of positron emission tomography scans before and after the lesion, using several dopaminergic tracers in parallel. We show that specific binding of [11C]nomifensine in the lesioned striatum disappears to a large extent (80-90%) as a result of the lesion, indicating a corresponding loss of striatal dopamine re-uptake binding sites and thus of the dopamine nerve terminal pool. The uptake of radioactivity in the striatum contralateral to the lesion remained unchanged. In parallel, an early increase in ipsilateral [11C]raclopride binding, indicating upregulation of dopamine D2 receptors, was seen following the presynaptic lesion. [11C]Deprenyl uptake, indicating monoamine oxidase type B enzyme concentration, did not change after the lesion.
1-Methyl-4-phenyl-1,2,3,6-tetrahydropyridine↗
Peripheral PMN cell activity in relation to treatment of juvenile periodontitis.
Ten patients with untreated juvenile periodontitis (JP) showing an increased generation rate of free oxygen radicals from their peripheral polymorphonuclear neutrophils (PMN) as measured by luminol enhanced chemiluminescence (CL) were rechecked after treatment. The PMN cells from eight patients still reacted with higher CL after stimulation with Staph. aureus opsonized with autologous serum when related to pair-matched controls. The increased CL was not caused by adsorption of serum factors from untreated JP patients when assayed with healthy PMN cells. The increased CL found in peripheral PMN cells from patients with JP thus depends very little on the disease activity.
Adolescent↗