| 1. |
- Lundquist, Ingmar, et al.
(författare)
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Monoamines in pancreatic islets of guinea pig, hamster, rat, and mouse determined by high performance liquid chromatography
- 1989
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Ingår i: Pancreas. - 0885-3177. ; 4:6, s. 662-667
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Tidskriftsartikel (refereegranskat)abstract
- Previous studies on the occurrence of catecholamines and serotonin in pancreatic islets using various histochemical and chemical methods have given widely different results. We therefore performed a comparative analysis of these amines in whole pancreas and islet tissue from hamster, guinea pig, rat, and mouse by the use of high performance liquid chromatography. Whole pancreas of guinea pig, hamster, and rat had a norepinephrine concentration of approximately 1.1 [mu]mol/kg of pancreatic wet weight. The mouse pancreas had less than one-half of that concentration. Epinephrine and dopamine concentrations were on the order of 0.02 [mu]mol/kg of pancreatic wet weight in all four species. The serotonin concentration was 2.1 [mu]mol/kg of pancreatic wet weight in the guinea pig pancreas and approximately 0.2 [mu]mol/kg in the other three species studied. The catecholamine concentrations were much higher in the pancreatic islets than in the exocrine pancreas. Thus, the norepinephrine concentration was approximately 35 [mu]mol/kg of islet wet weight in hamster islets and 5-10 [mu]mol/kg in rat, guinea pig, and mouse islets. The epinephrine concentration in islet tissue ranged between 1 and 7 [mu]mol/kg of islet wet weight and the dopamine concentration between 0.5 and 4 [mu]mol/kg except for guinea pig islets (12 [mu]mol/kg). The islet tissue in the mouse, rat, and guinea pig contained disproportionately more epinephrine and dopamine relative to norepinephrine than did the exocrine pancreas. Chemical sympathectomy (6- hydroxydopamine treatment) in the mouse reduced the norepinephrine and epinephrine concentrations in islet tissue to nondetectable levels, whereas the dopamine concentration was essentially unchanged, thus suggesting an extraneuronal source of this amine in addition to its occurrence in adrenergic nerves. The islets of hamster, rat, and mouse contained no serotonin, whereas guinea pig islets contained approximately 275 [mu]mol/kg of islet wet weight. We conclude that, although species differences exist, the pancreatic islets have markedly higher levels of catecholamines than the exocrine pancreas, and that serotonin occurs in the exocrine pancreas of all four species studied but in the endocrine pancreas only in the guinea pig.
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| 2. |
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| 3. |
- Reuterving, Carl-Olof, 1946-
(författare)
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Salivary glands and oral lesions in diabetes mellitus : an experimental and clinical study with special reference to the influence of metabolic control and duration of the disease
- 1987
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Diabetes mellitus is associated with several clinically significant abnormalities in the oral cavity and salivary glands, the most common being periodontitis, salivary gland enlargement and a sensation of dry mouth. The prevalence of dental caries in diabetics is mostly reported to be decreased or unaffected. Since there is a shortage of information concerning the influence of metabolic control and duration of diabetes on these abnormalities, the present studies were performed.Three-month-old rats were made alloxan-diabetic and investigated after one and twelve months’ duration of diabetes for oral lesions and feeding behavior. They had free access to a standard pellet diet and tap water. Streptococcus mutans and lactobacilli were naturally occurring. In diabetic rats the proportion of the oral flora which was lactobacilli was positively correlated to the blood glucose level. Untreated long-term alloxan-diabetic rats developed advanced periodontal disease and root surface caries in the molars at sites of interdental impaction of foreign material. The degree of alveolar bone loss was positively correlated to the blood glucose level. Diabetic rats were hyperphagic and had a longer total eating time, including day-time eating, mainly by having longer meals but no significant increase of meal frequency, as compared with non-diabetic animals. The untreated alloxan-diabetic rats developed reduced salivary gland weight which was of the same degree in short- and longterm diabetic animals. Short- and long-term untreated alloxan-diabetic rats showed a similar degree of morpho- metrically estimated lipid accumulation in the acinar cells of the submandibular glands, and the degree was positively correlated to the blood glucose level. However, lipid inclusion occurred only in rats with a morning nonfasting blood glucose level exceeding 15 mmol/L. The capillaries in the submandibular glands of the untreated long-term alloxan-diabetic rats had a significantly increased thickness of the basement membranes as compared with the observations in short-term diabetic and non-diabetic rats. Untreated alloxan-diabetic rats were also shown to have a decreased salivary flow rate compared with non-diabetic rats, and the decreased flow was negatively correlated to the blood glucose concentration. Salivary flow rate increased with the duration of the disease. The diabetic rats had increased salivary glucose levels, which were positively correlated to blood glucose values when the latter were above 15 mmol/L, suggesting a threshold mechanism for salivary glucose excretion. Insulin therapy reversed salivary flow rate and salivary glucose concentrations toward normal.Salivary investigations were performed in eleven diabetic patients on two occasions with different metabolic control. Salivary flow rate showed marked interindividual differences but was not significantly changed by improved metabolic control although several of the patients initially had severely deranged glucose metabolism. A positive correlation between the glucose concentration in blood and saliva was seen in the parotid saliva during secretory stimulation. No significant change in electrolytes, amylase or antimicrobial factors was found.
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| 4. |
- Agardh, Elisabet, et al.
(författare)
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The prevalence of retinopathy and associated medical risk factors in type I (insulin-dependent) diabetes mellitus
- 1989
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Ingår i: Journal of Internal Medicine. - 1365-2796. ; 226:1, s. 47-52
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Tidskriftsartikel (refereegranskat)abstract
- The prevalence of diabetic retinopathy and the associated medical risk factors, such as age at onset and duration of diabetes, metabolic control, blood pressure, albumin clearance and serum creatinine, were studied in 501 patients with type I diabetes mellitus. The prevalence of retinopathy, characterized as simplex, maculopathy, preproliferative, and proliferative, was 60.5%. Patients with retinopathy were younger at the onset of diabetes, and had a longer duration of disease. In patients with more than 10 years of diabetes, proliferative retinopathy was more frequent if onset was before they were 15 years old, despite the fact that the duration of diabetes did not differ. Patients with severe retinopathy had worse metabolic control, and were more frequently treated for hypertension. In addition, the systolic blood pressure was elevated in all groups of patients with any type of retinopathy, whereas the diastolic blood pressure was elevated only in patients with more severe forms. Patients with severe retinopathy also had higher levels of albumin clearance.
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| 5. |
- Torffvit, Ole, et al.
(författare)
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Exercise stimulation in insulin-dependent diabetics, normal increase in albuminuria with abnormal blood pressure response
- 1987
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Ingår i: Scandinavian Journal of Clinical & Laboratory Investigation. - 1502-7686. ; 47:3, s. 253-259
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Tidskriftsartikel (refereegranskat)abstract
- Increased urinary albumin excretion rate (AER), microalbuminuria, has been regarded as a sign of incipient nephropathy. The influence of exercise on AER was investigated in 10 male type I diabetics and in 12 age-matched male controls. The duration of diabetes was 7-31 years (median 14 years). The exercise tests were performed both as a combined submaximal workload-waterload test and as a maximal workload test. Urinary albumin was measured with an ELISA technique. During exercise in both tests, no difference was seen in the AER between diabetics and their controls. However, the increase in systolic blood pressure was significantly more marked in the diabetics. There was no correlation between the blood pressure response during exercise and the AER, neither in the diabetics, nor in their controls. It is concluded, that, increased blood pressure response during exercise does not necessarily result in increased AER in type I diabetics.
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| 6. |
- Olsson, M. Landin, et al.
(författare)
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Prolonged incubation in the two-colour immunofluorescence test increases the prevalence and titres of islet cell antibodies in Type 1 (insulin-dependent) diabetes mellitus
- 1987
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Ingår i: Diabetologia. - 0012-186X. ; 30:5, s. 327-332
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Tidskriftsartikel (refereegranskat)abstract
- The conventional indirect immunofluorescence test of islet cell antibodies was recently improved by the development of a two-colour immunofluorescence assay using a monoclonal proinsulin antibody to detect islet B cells. The aim of this study was to test whether in this new assay the prevalence and titre of ICA were affected by the time of incubation carried out in the presence of aprotinin (Trasylol) as an inhibitor of proteolysis. The end-point titre of ICA was therefore determined in sera from 70 children aged 0.6 to 15 years with recent onset Type 1 (insulin-dependent) diabetes mellitus, 50 healthy control subjects and 97 non-diabetic siblings of Type 1 diabetic children. In the conventional twocolour assay, ICA was positive in 53/70 (76%) Type 1 diabetic patients, 1/50 control subjects and 2/97 siblings after 30 min incubation. Prolonged incubation for 18 h increased the prevalence of ICA positive samples to 62/70 (89%) in the diabetic patients and to 2/50 in the control subjects, while the prevalence among the siblings was unchanged. Of the ICA positive non-diabetic subjects, one control child has a father with Type 1 diabetes, and one of the siblings subsequently developed Type 1 diabetes. In the diabetic patients the median titre was 1:32 for the 30 min incubation, and it increased to 1:64 for the 18 h incubation (p<0.001). A marked prozone effect was seen; 16% of the samples from the Type 1 diabetic children sera were negative at a 1:2 dilution, but were found positive at higher dilutions. In conclusion, an 18 h incubation increases the end point titres and the prevalence of ICA in the two-colour ICA assay in Type 1 diabetic children of recent onset. The prevalence and levels of ICA among these patients may be larger than hitherto expected.
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| 7. |
- Agardh, Carl-David, et al.
(författare)
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Plasma lipids and plasma lipoproteins in diabetics with and without proliferative retinopathy
- 1988
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Ingår i: Acta Medica Scandinavica. - 0001-6101. ; 223:2, s. 165-169
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Tidskriftsartikel (refereegranskat)abstract
- The single most important factor related to the development of diabetic retinopathy is the duration of diabetes. Little is known about the underlying mechanisms, but many factors have been suggested to be involved, among them derangements in plasma lipids and plasma lipoproteins. In the present study we examined the relation between plasma lipids, plasma lipoproteins, and the duration of diabetes in Type I diabetics with and without proliferative retinopathy. The duration of diabetes in the two groups was 12.2 +/- 2.8 and 21.5 +/- 9.0 years, respectively (mean +/- SD; p less than 0.01). Except for moderately low HDL levels, plasma lipid and lipoprotein concentrations were normal in both groups of patients. The levels of lipids and lipoproteins did not correlate with the duration of diabetes. Furthermore, no differences were seen between patients with and without proliferative retinopathy. Thus, the present study does not indicate that plasma lipids and plasma lipoproteins play any major role in the development of diabetic proliferative retinopathy.
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| 8. |
- Quensel, M, et al.
(författare)
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Nicotine does not affect plasma lipoprotein concentrations in healthy men
- 1989
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Ingår i: Scandinavian Journal of Clinical & Laboratory Investigation. - : Informa UK Limited. - 1502-7686 .- 0036-5513. ; 49:2, s. 149-153
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Tidskriftsartikel (refereegranskat)abstract
- The effects of nicotine administration (2 mg eight-times daily as nicotine chewing gum for two weeks) on plasma lipid and lipoprotein concentrations were studied in young healthy volunteers. Plasma levels of the nicotine metabolite, cotinine, reached levels comparable to those seen in smokers. Plasma concentrations of triglyceride, cholesterol, HDL cholesterol, LDL cholesterol, and apolipoproteins AI and B, were determined repeatedly before, during and after cessation of nicotine intake. All these variables, as well as the activities of lipoprotein lipase and hepatic lipase in post-heparin plasma, remained unchanged throughout the study. The results strongly suggest that the effects of smoking on plasma lipoprotein metabolism are not mediated via nicotine, and indicate that nicotine chewing gum, when used therapeutically in anti-smoking programmes, does not carry the same metabolic side effects as smoking.
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| 9. |
- Agardh, Elisabet, et al.
(författare)
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Normal eyes in type 1 diabetics stay normal after one year of treatment with continuous subcutaneous insulin pump
- 1986
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Ingår i: Acta Ophthalmologica. - 0001-639X. ; 64:5, s. 530-532
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Tidskriftsartikel (refereegranskat)abstract
- Seven patients with type 1 diabetes mellitus were restored to near normoglycaemia by treatment with continuous subcutaneous insulin infusion pumps (CSII). The patients were examined with ophthalmoscopy, fundus photography and fluorescein angiography before and one year after the start of CSII treatment. In addition, ophthalmoscopy was performed after 6 months of treatment. All 14 eyes were normal prior to the CSII treatment and none had developed any signs of retinopathy after 6 months or 1 year. It is concluded that metabolic control can be near normalized with CSII treatment without any risk for development of diabetic microangiopathy in type 1 diabetics with normal eyes.
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| 10. |
- Hartling, Svend G, et al.
(författare)
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Elevated proinsulin in healthy siblings of IDDM patients independent of HLA identity
- 1989
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Ingår i: Diabetes. - : American Diabetes Association. - 0012-1797 .- 1939-327X. ; 38:10, s. 1271-1274
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Tidskriftsartikel (refereegranskat)abstract
- Based on the recent demonstration of elevated serum proinsulin levels in cystic fibrosis patients with impaired glucose tolerance, it was hypothesized that proinsulin could be an indicator of altered β-cell function. We therefore analyzed fasting proinsulin levels in 99 siblings of insulin-dependent diabetes mellitus (IDDM) patients, most of them discordant for diabetes for >6 yr. The results from this group were compared with the results from 41 healthy age- and sex-matched control subjects with no family history of diabetes. Median (range) fasting proinsulin in siblings was 8.9 pM (1.7–58 pM) vs. 3.8 pM (<1.2–28 pM) in control subjects (P < .00001). There was no difference between the groups in fasting blood glucose concentrations. Both groups had fasting insulin concentrations within the normal range with a tendency toward lower values in the siblings: 108 pM (60–237 pM) vs. 118 pM (71–175 pM) (P = .07). The 99 siblings were subdivided into groups according to HLA sharing with their diabetic proband. The concentration of proinsulin, insulin, and blood glucose among the groups of 33 HLA-identical, 40 HLA-haploidentical, and 26 nonidentical siblings did not differ significantly. The fasting proinsulin level did not correlate with fasting levels of insulin, blood glucose, age, or body weight. We conclude that fasting proinsulin is elevated in healthy siblings of IDDM patients, whereas fasting insulin is normal or slightly decreased independent of HLA identity with their diabetic sibling. Elevated proinsulin levels could represent a family trait, perhaps mirroring a β-cell more vulnerable to destruction, or it could reflect previous β-cell damage that does not lead to IDDM.
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