Biomedical subjects
Publications and source records attributed to G Lundgren.
Explore the source record for details and available documents.
Explore the source record for details and available documents.
A new method for analysis of virus-specific Immunoglobulin G (IgG) subclasses was developed using indirect immunofluorescence. Three hundred thirty-three serum samples from patients with different types of Epstein-Barr virus (EBV)-associated diseases and healthy controls were examined for subclass distribution to the virus capsid antigen (EBV VCA). EBV-VCA-expressing cell preparations were incubated with patient serum followed by monoclonal antibodies to human IgG1 through IgG4 and labelled anti-mouse IgG. Virus-specific IgG1 was found to be the dominant antibody. The titers for IgG1 and total Ig to EBV VCA correlated well. EBV VCA-specific IgG2 was not found. EBV VCA-specific IgG3 in a titer of greater than or equal to 10 was found in 33% of healthy seropositive donors, in 97% of patients with suspected reactivated EBV infection, and in 100% of symptomatic patients with suspected reactivated EBV infection. EBV VCA specific IgG3 occurred in 90% of placebo-treated compared to 30% in long-term acyclovir-treated bone marrow transplant recipients, indicating more frequent reactivations in the former group. IgG4 to VCA was infrequently found in seropositive persons. In serum samples from patients with nasopharyngeal carcinoma and high EBV VCA Ig and IgA titers, IgG4 to VCA was always present. Analysis of EBV VCA specific IgG subclasses seems to be valuable for the diagnosis of reactivated EBV infection.
Twenty eight consecutive combined renal and pancreatic transplantations with enteric exocrine diversion were performed between June 1984 and May 1986. The one-year actuarial patient survival and renal and pancreatic graft survival were 90%, 67%, and 69%, respectively. Nineteen pancreatic grafts and eighteen renal grafts are currently functioning at 1-24 months. Of the pancreatic graft losses only 2 were attributable to nonimmunological complications. No pancreatic graft was lost due to pancreaticoenteric leakage or vascular thrombosis. This was achieved by reducing the cold ischemia time and by adopting an aggressive anticoagulant policy. In all patients with functioning grafts the fasting blood glucose, glycosylated hemoglobin level, and oral glucose tolerance test were normal. The intravenous glucose tolerance test was normal in most of the patients but subnormal in some.
The effect of diazepam on the acetylcholine (ACh) synthesizing system has been studied in mouse brain in vivo. ACh and choline (Ch) were analyzed by gas chromatography - mass spectrometry using deuterated internal standards. Turnover of ACh was studied by following the incorporation of Ch into ACh after an intravenous injection of [2H6]-Ch. The mice were killed by focussed microwave irradiation on the head. Diazepam was found to increase the endogenous level of Ch, while the concentration of [2H6]-Ch was only half of that of the controls. The incorporation of [2H6]-Ch into [2H6]-ACh was decreased, while the endogenous level of ACh was slightly increased. The turnover rate of ACh was decreased, consistent with a decrease in neuronal excitability induced by diazepam. The elevated endogenous Ch-level and the lower concentration of [2H6]-Ch in the brain, might be explained by an effect of diazepam on the Ch-transport across the blood-brain barrier. This theory is supported by experiments where levels of endogenous and [2H6]-labelled Ch were analyzed in blood following an intravenous injection of [2H6]-Ch. The [2H6]-Ch was found to be eliminated faster in blood from diazepam treated mice. The increased blood level of endogenous Ch, induced by the [2H6]-Ch injection also returned more rapidly to normal in these animals. This is consistent with peripheral Ch being eliminated faster when the central Ch supply is decreased.
Studies of muscarinic receptor concentration and comparative binding assays of agonists and antagonists are presently done in vitro by incubation and measurement of the binding to tissue homogenates of the radiolabelled potent antagonists 3H-scopolamine or 3H-quinuclidinyl benzilate. We have developed a technique based on gas chromatography-mass spectrometry that allows studies of the muscarinic receptor concentration to be performed in vivo under physiologic conditions. By injecting the optical antipodes of atropine, D- and L-hyoscyamine separately in mice and following their kinetics in different parts of the brain it was possible to separate the specific receptor binding of the active antipode L-hyoscyamine from that of the inactive antipode D-hyoscyamine, representing unspecific binding. Two hrs after the administration of L-hyoscyamine, 2 mg/kg intravenously, its concentration in brain was found to represent "maximum" specific binding. The physiological significance of specifically bound L-hyoscyamine was tested on its blocking effect on oxotremorine induced tremor.
Diazepam has previously been shown to affect the acetylcholine synthesizing system in mouse brain. This paper reports studies on the effect of diazepam on muscarinic receptor density and on pharmacological effects of oxotremorine. The receptor density was studied using a new technique that allows such studies to be performed in vivo under physiological conditions. The method is based on the fact that L-hyoscyamine, the active antipode of atropine, binds specifically to muscarinic receptors in the brain, and can be measured with high sensitivity by gas chromatography--mass spectrometry. Diazepam was found to modify the binding properties of muscarinic receptors in CNS, thereby decreasing the functional receptor pool. It also prevented tremor induced by the muscarinic agonist oxotremorine. Diazepam could however not prevent the hypothermia induced, but rather accentuated this effect of oxotremorine. It is concluded that diazepam, directly or indirectly, influences the effect of cholinergic stimulators by modulating the size of the muscarinic receptor pool.
Explore the source record for details and available documents.
Tissue specimens from hypotonic and normotonic human urinary bladders were investigated histochemically, chemically and neuropharmacologically. In hypotonic bladders the density of acetylcholinesterase (AChE)-positive nerves was markedly reduced and the nerve AChE staining intensity was weak. The concentration of acetylcholine was significantly lower than in specimens from normotonic bladders. At field stimulation the contractions were weak. The observations indicated that sparse cholinergic innervation and reduced acetylcholine synthesis are important for the impaired contractility in idiopathic dystonic bladder.
Explore the source record for details and available documents.
Explore the source record for details and available documents.
Explore the source record for details and available documents.
Explore the source record for details and available documents.
Explore the source record for details and available documents.
Pretransplant blood transfusions had no beneficial effect on the graft survival rate, the rejection frequency, or the quality of graft function in a case material consisting of 928 cadaveric kidney transplant recipients treated with 3 different CsA dose protocols. When younger recipients, PRA-negative recipients, or recipients receiving poorly HLA-matched kidneys were analyzed separately, there was still no transfusion effect. In the most recent series, the one-year graft survival rate was 84% among 164 nontransfused patients, and in 73 nontransfused patients under 50 years of age it was 90%. We conclude that with present day immunosuppressive therapy, based on CsA, there is no case for pretreatment blood transfusions. Indeed, this practice might place the renal transplant patient at a disadvantage.
Explore the source record for details and available documents.
Explore the source record for details and available documents.
Explore the source record for details and available documents.