Search PubMed⌕ Search

Biomedical subjects

P Eriksson

Publications and source records attributed to P Eriksson.

At least 145 records · Page 8Linked to original sources

Biochemical markers of renal disease in primary Sjögren's syndrome.

Primary Sjögren's syndrome (SS) is characterized by an inflammatory process in the salivary and lacrimal glands, but the kidneys may also be involved. Renal tubular functions were studied in 27 patients with SS, all females, age 37-78. Both SS-patients with and without known distal renal tubular acidosis (dRTA) were included, dRTA was found in 18/27 (67%), impaired urine concentrating ability in 13/27 (48%). Hypocitraturia was identified in 20/27 (74%) and reduced tubular reabsorption of phosphate (TRP%) in 18/27 (67%). Tubular proteinuria (alpha 1-mikroglobulin) was present in 11/24 (46%), and tubular enzymuria (NAG) in 7/24 (29%). Hypocitraturia and/or dRTA were found in all patients with any kind of abnormal renal tubular function test. All except one of the patients with dRTA not treated with sodium bicarbonate had hypocitraturia. We conclude that distal tubular dysfunction was common in our SS-patients, but a concommitant proximal dysfunction was also seen. Determination of urinary citrate represents a valuable test for detection of renal disease in SS.

Acetylglucosaminidase↗

Dynamics of left ventricular thrombi in patients with acute anterior myocardial infarction treated with thrombolytics.

BACKGROUND: Limited data exist concerning left ventricular thrombi during and after hospitalization in patients treated according to modern principles. The purpose of the present study was to examine the formation and resolution of left ventricular thrombi during the first month in patients with acute anterior myocardial infarction treated with streptokinase and aspirin. METHODS: Seventy-seven consecutive patients were studied prospectively during the hospital stay and 1-month follow-up study. Aspirin was used routinely, whereas anticoagulants were only used after a decision by the attending physician. Echocardiography was performed within 3 days of admission, before hospital discharge and after 1 month of follow-up. RESULTS: At the first examination, 17 of 77 patients (22%) had a thrombus. At discharge, 73 patients remained in the study. In five (31%) of the 16 patients with early thrombus, the thrombus persisted; in 18 (32%) of the 57 patients without early thrombus, a new thrombus was diagnosed. One month later, 65 patients remained eligible for follow-up study. In three of 20 patients (15%) the thrombus from the second examination persisted and in four of 45 patients (9%) a new thrombus was diagnosed. The disappearance rate between the second and third examination was high irrespective of whether patients were treated with anticoagulants (eight of nine, 89%) or not (nine of 11, 82%). Extensive left ventricular segmental dysfunction and signs of congestive heart failure were associated with the appearance of a left ventricular thrombus. No embolic events were recorded. CONCLUSION: In patients with anterior myocardial infarction treated with streptokinase and aspirin the development and disappearance of left ventricular thrombi is a highly dynamic process. A large proportion of thrombi resolve without additional anticoagulant therapy.

Adult↗

Neonatal exposure to a type-I pyrethroid (bioallethrin) induces dose-response changes in brain muscarinic receptors and behaviour in neonatal and adult mice.

This study shows that neonatal exposure to the insecticide bioallethrin has a dose-dependent effect on muscarinic cholinergic receptors (MAChR) in the neonatal mouse, leading to permanent changes in MAChR and in spontaneous behaviour in adult mice. Neonatal NMRI mice, given oral doses of either bioallethrin or the vehicle, once daily between the 10th and 16th postnatal day, were killed at the age of 17 days or 1 week after the spontaneous motor behaviour tests at 4 months. The MAChR were assayed in the cerebral cortex by using the antagonist quinuclidinyl benzilate ([3H]QNB) and the agonist carbachol. In the 17-day-old mice bioallethrin exposure elicited a significant dose-dependent increase in the specific [3H]QNB binding. The competition study showed that the proportion of low-affinity binding was significantly increased in the 17-day-old mice compared with controls. In the adult mouse there was a significant dose-dependent decrease in specific [3H]QNB binding. In these adult mice the behavioural variables 'locomotion' and 'total activity' showed significant (P < or = 0.01) dose-dependent increases at all doses up to and including 0.70 mg/kg b.wt.

Aging↗

IgG2 deficiency in primary Sjögren's syndrome and hypergammaglobulinemic purpura.

Total IgG and IgG subclasses were studied in 34 patients with primary Sjögren's syndrome and 4 with hypergammaglobulinemic purpura. Total IgG was elevated in 30/34 patients with Sjögren's syndrome. IgG1 increase was responsible for the main part of total IgG increase, contrasting with low levels of IgG2. The difference in IgG1/IgG2 ratio between 38 patients as a group and 40 normal controls was statistically highly significant, but was not seen in all patients. Six patients had markedly low levels of IgG2, but only two had severe repeated respiratory infections. These observations probably reflect selective autoantibody restriction to the IgG1 subclass. We conclude that patients with Sjögren's syndrome may be IgG2 subclass deficient despite elevated levels of total IgG, but also that such deficiency in most instances does not cause a tendency to infections. IgG subclass analysis may be of value to characterize polyclonal IgG increase, since IgG1 subclass predominance often indicates autoimmune disease.

Adult↗

IgG subclasses of anti-SS-A/Ro in patients with primary Sjögren's syndrome.

Patients with primary Sjögren's syndrome mostly have high levels of polyclonal IgG, and subclass analysis frequently shows selective IgG1 increase with low IgG2. In this study IgG subclass profiles of anti-SS-A/Ro were examined using ELISA technique. Results show marked IgG subclass restriction of anti-SS-A/Ro autoantibodies (high IgG1/low IgG2). Comparison of the levels of specific IgG subclass autoantibodies with total levels of the corresponding subclass disclosed divergence regarding IgG2, IgG3, and IgG4, but not IgG1. Thus, total levels of IgG1 paralleled the levels of IgG1 anti-SS-A antibodies. Specific autoantibodies of IgG2 subclass could not be detected despite low or normal levels of total IgG2. Elevated levels of specific IgG3 and IgG4 antibodies were seen, although total levels of the corresponding subclasses were within normal limits. These findings may possibly be of relevance with regard to antigen-driven activation of autoantibody-producing plasma cell clones.

Autoantibodies↗

Physiological responses during wheelchair racing in quadriplegics and paraplegics.

The purposes of this study were: (1) to compare the physiological responses during simulated wheelchair racing (SR) between male quadriplegics and paraplegics, (2) to test the validity of the SR against a track race (TR) and (3) to examine the relationship between the peak oxygen uptake (peak VO2) and wheeling velocity (WV) during the SR and TR. Seven quadriplegics (C5-8 lesions) and six paraplegics (T5-L4 lesions) completed (1) an incremental wheelchair velocity test, (2) a SR (1.6 km for quadriplegics and 3.2 km for paraplegics), and (3) an indoor TR of the same distance. The subjects performed the incremental velocity test and SR in their personal wheelchairs mounted on a roller system interfaced with customized software programmed to provide velocity and distance feedback. Physiological responses were monitored using an automated metabolic cart and electrocardiogram. Blood lactate concentration [La] was determined from finger prick samples. Peak VO2 and peak heart rate (peak HR) were significantly higher in the paraplegics compared to quadriplegics: 1.90 +/- 0.54 vs 1.07 +/- 0.35 l/min, and 188 +/- 11 beats/min vs 117 +/- 12 beats/min respectively. The paraplegics exercised at significantly (p < 0.05) higher percentages of peak VO2 and peak HR during the SR compared to quadriplegics (95% vs 76% and 95% vs 86%, respectively). No significant relationships (p < 0.05) were observed between the peak VO2 and WV during the SR and TR in either group.(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗

Declining hospital mortality in acute myocardial infarction.

Beta-blockers, nitrates, aspirin and thrombolytic drugs have each separately been shown to reduce mortality in acute myocardial infarction, but the effect of these treatments combined during routine coronary care has not been assessed. The coronary care unit at Ostra Hospital services a stable community of 250,000 inhabitants. Since 1984 all patients have been entered into a computerized database. In addition, information on age, sex, discharge diagnosis and hospital outcome is also available for patients admitted between 1979 and 1983. In 1984, routine treatment with intravenous beta-blockers was introduced, to be followed in 1986 by intravenous nitroglycerin and in 1988 by aspirin in all patients without contraindications. Since 1988, intravenous thrombolytic treatment has been also given routinely to all patients with ST-elevation and chest pain < 6 h. Despite a similar number of patients and an increasing median age, the in-hospital mortality has declined from 18.5% in 1979 to 11.8% in 1990 (P < 0.01). It is concluded that mortality from acute myocardial infarction has declined by almost 40% since 1979. This reduction cannot be explained by a single major therapeutic intervention but may be attributed to the combined use of multi-lead monitoring, early use of beta-blockers, nitroglycerin, aspirin and thrombolytic agents.

Adrenergic beta-Antagonists↗

Relationships of thrombosis and fibrinolysis to atherosclerosis.

The importance of the haemostatic system in predisposing to or precipitating coronary heart disease has gained increasing recognition. Major advances have been made in our understanding of the mechanisms resulting in hypercoagulability and impaired fibrinolytic function. Emphasis is placed on the role of dyslipoproteinaemia and insulin resistance.

Arteriosclerosis↗

Gi-mediated muscarinic adenylyl cyclase inhibition in timolol-treated stunned porcine myocardium.

The Gi-mediated muscarinic receptor-adenylyl cyclase system was examined in stunned myocardium induced by either three or five brief ischaemic periods after beta-adrenoceptor blockade by timolol (0.1 mg kg-1). The mid-left anterior descending coronary artery was occluded for 2, 10 and 2 min in four pigs, and for 2, 2, 5, 10 and 2 min in four other pigs. All the ischaemic periods were separated by 30 min of reperfusion and the biopsies were obtained 60 min after the last ischaemic period. Segment length function was measured in the ischaemic region and in the control region supplied by the left circumflex artery. In the two groups, the percentage systolic shortening was reduced equally, to 59 +/- 9 and 58 +/- 10% of control in the region subjected to ischaemia and only minimally in the control region. The biopsies from the stunned region from both groups showed: (1) no change in either the affinity for carbachol or the number of binding sites of the muscarinic receptors; (2) no alterations in messenger RNA encoding for the alpha subunit-2 of the inhibitory guanine nucleotide binding protein, as demonstrated by northern blot and solution hybridization; (3) no change in membrane-bound inhibitory guanine nucleotide binding protein, as shown by enzyme immunoassay utilizing a specific anti-peptide antibody, and (4) unchanged inhibition of stimulated adenylyl cyclase activity. These results suggest that there is an intact inhibitory guanine nucleotide binding protein-mediated muscarinic receptor adenylyl cyclase system in the stunned porcine myocardium.

Adenylyl Cyclase Inhibitors↗

Estradiol regulation of mRNA expression of stimulatory G-protein alpha-subunit in white adipose tissue from female rats.

Adipose tissue has been recognized as a major peripheral metabolic target of estrogens. The present study was addressed to examine in female rats whether differences in the adipose tissue mRNA expression of alpha-subunit of stimulatory (Gs) and/or inhibitory (Gi) G-proteins exist between intact and ovariectomized rats, the latter with or without estradiol or testosterone treatment. The fat cell membrane protein amount of Gs and Gi alpha-subunit also was examined. All these parameters were evaluated in parametrial fat tissue samples obtained from 40 female Sprague-Dawley rats. A group of rats (N = 20) was investigated for evaluation of mRNA expression and another group (N = 20) for quantification of the protein amount of Gs and Gi alpha-subunit. Each group was represented by five control rats (sham-operated), five ovariectomized (OVX) rats, five ovariectomized rats treated with estradiol (OVXE) and five ovariectomized rats treated with testosterone (OVXT). Ribonucleic acid extracted from adipose tissue and analyzed by northern blot with G alpha s, G alpha i-3 cRNA probes revealed three major bands with estimated sizes of 1.9, 3.5 and 2.35 kb, respectively. Messenger RNA quantitative analysis, by a solution of hybridization RNAase protection assay on total nucleic acid samples, showed that the amount of G alpha i-1 and G alpha i-2 mRNA was similar within the different groups, whereas the G alpha s mRNA was significantly less abundant (p < 0.01) in OVX and OVXT rats than in control or OVXE rats. No difference in G alpha s mRNA content was found between control and OVXE rats.(ABSTRACT TRUNCATED AT 250 WORDS)

Adipose Tissue↗

Long-term improvement of glycemic control by insulin treatment in NIDDM patients with secondary failure.

OBJECTIVE: To evaluate the long-term efficacy of insulin treatment of patients with non-insulin-dependent diabetes mellitus (NIDDM) and secondary failure to oral hypoglycemic agents. RESEARCH DESIGN AND METHODS: Twenty-one NIDDM patients with secondary failure were studied while they were still on oral agents. Then they were switched to insulin treatment, and after a median of 27 months, a long-term evaluation was conducted. RESULTS: At the long-term evaluation, metabolic control was still markedly improved by insulin treatment, with reduction of HbA1c from 8.8 +/- 0.2 (mean +/- SE) to 6.9 +/- 0.3% (P < 0.0001), lowering of very-low-density lipoprotein (VLDL) cholesterol concentration from 0.97 +/- 0.3 to 0.69 +/- 0.1 mM (P < 0.03), and lowering of total triglycerides from 2.8 +/- 0.6 to 1.8 +/- 0.3 mM (P < 0.005), mainly due to reduction of VLDL triglycerides. Body weight increased during the first year, but not thereafter (71.3 +/- 2.5 kg during oral treatment, 78.9 +/- 2.9 and 79.8 +/- 3.2 kg after 12 and 36 months of insulin treatment, respectively). Blood pressure did not change. Fasting and postprandial insulin concentrations increased, and C-peptide concentrations were lowered. CONCLUSIONS: Improvements of glycemic control and lipoprotein concentrations in patients with NIDDM and secondary failure persist also after insulin treatment for 2-3 years in spite of weight gain and hyperinsulinemia.

Adult↗

Messenger RNA of G-proteins alpha-subunit in rat brown adipose tissue.

The present study was addressed to quantify the steady-state mRNA levels for the alpha subunit of stimulatory (Gs) and inhibitory (Gi-1 and Gi-2) G-proteins in brown (interscapular) male rat adipose tissue (n = 6 rats). The quantification of specific mRNA, estimated using a solution hybridization RNAse protection assay, showed that the amounts of G alpha i-1, G alpha i-2 and G alpha s mRNA were 0.88 +/- 0.28 amol/microgram DNA, 76 +/- 4 amol/micrograms DNA and 460 +/- 16 amol/micrograms DNA, respectively. When the amounts of G alpha i-1 and G alpha i-2 and G alpha s mRNA in brown adipose tissue were compared with those in epididymal white adipose tissue (obtained from the same rats), G alpha i-1 and G alpha i-2 mRNA levels were very similar between brown and white adipose tissue, whereas the level of G alpha s mRNA was significantly higher in brown than in white fat tissue (P < 0.001). In conclusion, the present study shows the steady-state levels of mRNA for the alpha subunit of Gs, Gi-1 and Gi-2 in rat brown fat and suggests that the quantity of G alpha s mRNA is higher in brown than in white adipose tissue. Further studies are needed to explain the possible physiological importance of these findings.

Adipose Tissue↗

Computer-assisted evaluation of dipyridamole thallium-201 SPECT in patients with aortic stenosis.

UNLABELLED: Dipyridamole SPECT detects significant coronary artery disease (CAD) in patients without aortic stenosis. This study was done to establish normal 201Tl distribution limits in patients with aortic stenosis and to apply these normal limits to patients with aortic stenosis and angiographically significant CAD (> or = 75% area reduction). METHODS: Fifty-two patients (mean age 68 yr; mean valve area 0.67 cm2) were examined with 201Tl SPECT after dipyridamole infusion (0.56 mg/kg during 4 min). After tomographic reconstruction, basal, mid-ventricular and apical short-axis slices were selected. The highest activity in each six-degree segment was normalized to the maximal activity of each slice. RESULTS: Significant CAD was found in 24 patients. Five patients without CAD, but with localized hypokinesia or left bundle-branch block, were excluded from the reference group which finally consisted of 16 patients. Sensitivity for CAD was 88% when the lowest relative activity in each segment was used as the lower limit of normal. With -2 s.d. and -2.5 s.d. curves the sensitivity was 83% and 75%, respectively. Gender-specific limits were not used. Nonsignificant CAD was found in seven patients (< 75% stenoses). CONCLUSIONS: This study presents the normal distribution of 201Tl uptake for patients with aortic stenosis, using dipyridamole SPECT. The range method had the highest sensitivity for detection of significant CAD.

Adult↗

The glucocorticoid receptor acts as an antirepressor in receptor-dependent in vitro transcription.

Glucocorticoid-receptor-dependent and glucocorticoid-response-element-dependent in vitro transcription was established using a crude nuclear extract and purified glucocorticoid receptor from rat liver. The capacity of glucocorticoid receptor to stimulate in vitro transcription was only detectable when basal transcription, i.e. transcription in the absence of glucocorticoid receptor, had been repressed. Transcriptional repression was achieved either by adding purified histone H1, or by lowering the amount of DNA template relative to the amount of crude nuclear extract. Glucocorticoid receptor caused a 1.1 +/- 0.7-fold stimulation of transcription from the mouse-mammary-tumor-virus promoter when basal transcription was not repressed, and a 7.0 +/- 1.5-fold stimulation when basal transcription had been repressed by addition of histone H1. Similar results were obtained when using a minimal promoter consisting of two glucocorticoid-response elements and a TATA box. Our data suggest that glucocorticoid receptor stimulates in vitro transcription by an antirepression mechanism.

Animals↗

Neonatal exposure to DDT induces increased susceptibility to pyrethroid (bioallethrin) exposure at adult age.--Changes in cholinergic muscarinic receptor and behavioural variables.

We have recently reported that DDT and the pyrethroid bioallethrin cause similar changes in the brain muscarinic cholinergic receptors (MAChR) and behavioural disturbances in the neonatal and adult mouse when given to neonatal mice during the peak of rapid brain growth. In the present study the interaction between neonatal and adult exposure to DDT and bioallethrin, respectively, is explored. Ten-day-old NMRI mice received a single low oral dose of DDT (0.5 mg/kg body wt). At adult age (5 months) the mice received bioallethrin 0.7 mg/kg body wt./day per os for 7 days. Mice used as controls received a 20% fat emulsion vehicle. The spontaneous behavioural tests revealed significant differences, both in mice treated neonatally with DDT and receiving bioallethrin as adults and in mice receiving the vehicle as neonates and bioallethrin as adults, compared with their corresponding controls. However, the behavioural changes developed in mutually opposite directions. Significant changes in MAChR, assayed in the P2 fraction of the cerebral cortex by using the muscarinic antagonist, quinuclidinyl benzilate ([3H]QNB) and agonist carbachol, was only observed in animals receiving DDT as neonates and bioallethrin as adults. The present study indicates an increased susceptibility in the cholinergic muscarinic receptors and a different behaviour reaction in animals already exposed to DDT (at a physiologically relevant dose), when again exposed to a similar neurotoxic agent as adults.

Administration, Oral↗

Neonatal exposure to paraquat or MPTP induces permanent changes in striatum dopamine and behavior in adult mice.

We have recently reported that environmental toxicants, such as DDT, PCBs, pyrethroids, and nicotine can induce permanent functional and neurochemical changes in adult mice when given to neonatal mice during the peak of rapid brain growth. In the present investigation the neurotoxic effects following neonatal exposure to paraquat (N,N'-dimethyl-4,4'-bipyridylium), a broad-spectrum herbicide with structural similarity to the 1-methyl-4-phenylpyridium ion (MPP+), the active metabolite of 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) which can induce Parkinson's syndrome, and MPTP were studied. Five groups of mice were given paraquat or MPTP orally: group 1, vehicle; groups 2 and 3, MPTP 0.3 and 20 mg/kg; groups 4 and 5, paraquat 0.07 and 0.36 mg/kg when 10 and 11 days old. Neonatal spontaneous motor activity was tested on Day 18 in mice given paraquat 0.36 mg/kg body wt. Adult spontaneous motor activity testing was performed at ages 60 and 120 days. On Day 125 the mice were decapitated and the contents of dopamine (DA), serotonin (5-HT), and metabolites in striatum were analyzed. The results may be summarized as follows: (1) No signs of acute toxicity or differences in weight gain were observed in any of the groups. Nor was any respiratory distress or motor performance dysfunction evident on Day 18 in mice given paraquat 0.36 mg/kg body wt. (2) The behavioral tests at 60 days of age showed a marked hypoactive condition in the mice given paraquat (at both doses) and MPTP (at both doses). (3) At the age of 120 days the hypoactive behavior persisted and appeared even more pronounced. (4) The high doses of MPTP and paraquat--and to a less extent the low doses--reduced the striatal content of DA and metabolites without affecting 5-HT. The altered behavior, together with the dose-dependent reduction of DA and metabolites in neostriata in this study, further demonstrates the susceptibility to low-dose exposure to environmental pollutants during the neonatal period.

Animals↗

The response of central glia to peripheral nerve injury.

Microglial and astroglial cells undergo prompt responses to peripheral motor and sensory axon injury. These responses include proliferation of microglial cells as well as hypertrophy and increased levels of glial fibrillary acidic protein around the axotomized motoneurons and in the central projection territories of peripherally axotomized sensory ganglion cells. Proliferating microglial cells migrate towards reacting motoneurons, however, without directly apposing their cell membrane. Astroglial cells, on the other hand, increase their structural interrelationship with reacting motoneurons, seemingly at the expense of some presynaptic terminals. In sensory projection areas, microglial cells phagocytose degenerating axons and terminals. Beyond these observations, the functional role of the central glial cell response to peripheral nerve injury is obscure.

Animals↗