11. |
- Ekelund, Ulf, et al.
(author)
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Myogenic vascular regulation in skeletal muscle in vivo is not dependent of endothelium-derived nitric oxide
- 1992
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In: Acta Physiologica Scandinavica. - 0001-6772. ; 144:2, s. 199-207
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Journal article (peer-reviewed)abstract
- The hypothesis, based on in vitro experiments on large conduit arteries, that endothelium-derived nitric oxide is a mediator of vascular myogenic reactivity was tested in cat gastrocnemius muscle in vivo. This was done by comparing, in the absence and presence of effective endothelium-derived nitric oxide blockade by the specific inhibitors NG-monomethyl-L-arginine or NG-nitro-L-arginine methyl ester, myogenic responses in defined consecutive vascular sections to dynamic vascular transmural pressure stimuli, to arterial occlusion (reactive hyperaemia), and to arterial pressure changes (autoregulation of blood flow and capillary pressure). The results demonstrated that the myogenic vascular reactivity to quick ramp transmural pressure stimuli was not attenuated by endothelium-derived nitric oxide blockade, but rather reinforced. The amplitude of the reactive hyperaemia response was unaffected by endothelium-derived nitric oxide blockade, but its duration was shortened because of faster myogenic constriction, especially of large-bore arterial resistance vessels greater than 25 microns, in the recovery phase. Both the improved myogenic responsiveness to transmural pressure stimuli and the shortening of the reactive hyperaemia by endothelium-derived nitric oxide blockade suggested that endothelium-derived nitric oxide released in vivo acts as a 'metabolic' factor which certainly does not improve, but rather depresses myogenic vascular reactivity. Autoregulation of blood flow and capillary pressure were well preserved in the presence of endothelium-derived nitric oxide blockade. It was concluded from the results of these multifaceted tests that myogenic vascular regulation in skeletal muscle in vivo seems independent of endothelium-derived nitric oxide.(ABSTRACT TRUNCATED AT 250 WORDS)
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12. |
- Sjöberg, Inga, 1946-
(author)
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The vagina : morphological, functional and ecological aspects
- 1991
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Doctoral thesis (other academic/artistic)abstract
- The vagina is one organ of the body which has not been studied exhaustively. Moreover, most of the studies found in the contemporary literature have been performed on women affected by a variety of genital diseases.In the present study the vaginal epithelium was examined with a histological method, morphometry, whereby cyclical changes related to hormonal variation during the menstrual cycle were demonstrated. Determination of the quantity of estrogen receptors in the vaginal epithelium on two occasions during the menstrual cycle revealed a significantly greater number in the follicular than in the luteal phase. The results of these studies indicate the presence of a menstrual variation in the vaginal epithelium comparable to that in the endometrium.Phenoxymethylpenicillin (pcV) was used as a marker substance to study the dynamics of the transport mechanisms into the vagina. PcV was found to accumulate in the vaginal fluid and high concentrations persisted for a long period of time. In hysterectomized women, the appearance of pcV in the vaginal fluid followed the same pattern. Consequently, the substance is transported through the vaginal wall and need not enter with the secretions from the internal genitalia. The greatest concentration of pcV was in the distal portion of the vagina, possibly due to the specific internal circulation of fluid within the vagina.Bacterial vaginosis as an example of an ‘ecological disease’ has been studied with regard to the formation of endotoxin, a constituent of the cell wall of Gram- negative bacteria. Large amounts of endotoxin were found and the clinical implication of this finding has been pointed out.Furthermore, the influence of pcV on the vaginal microbial flora of healthy women has been investigated. A change from a situation with predominance of lactobacilli to the appearance of Gram-negative rods was observed. In one of the women the lactobacilli disappeared completely and were replaced by E. coliand high levels of endotoxin in the vaginal fluid were found. This study demonstrates the complexity of the ecological balance of the vaginal microbial flora and illustrates the difficulty of defining a ‘normal’ vaginal condition. Is there any unquestionable state of ‘normality’ even in a healthy woman free from symptoms of genital disease?
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13. |
- Torffvit, Ole, et al.
(author)
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A study of exercise-induced microalbuminuria in type I (insulin-dependent) diabetes mellitus
- 1991
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In: Scandinavian Journal of Urology and Nephrology. - : Informa UK Limited. - 0036-5599 .- 1651-2065. ; 25:1, s. 39-43
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Journal article (peer-reviewed)abstract
- Microalbuminuria is thought to be an important prognostic factor in diabetes mellitus. To study the influence of changes in blood pressure on the development of microalbuminuria during exercise, two exercise tests were carried out. A total of 32 insulin dependent diabetic men whose age at onset was less than 30 years, mean duration of diabetes 14 years (range 7 to 21) and mean age 29 years (range 21 to 40), and who did not have albuminuria (N-labstix negative) were studied. The diabetic patients were compared with a total of 29 age-matched male control subjects. Urinary albumin excretion was measured during two exercise tests: at a standardised workload (150 W) for 30 min, and at a standardised heart rate for 25 min. The diabetic patients had higher albumin excretion rates during both exercise tests compared with the control subjects. Blood pressure and heart rate during exercise were significantly higher in diabetic patients compared with control subjects in the standardised workload test. If the test was individualised to achieve the same standardised heart rate there was no significant difference in blood pressure between the diabetic patients and the control subjects. These results indicate that the diabetic kidneys were more sensitive than the healthy kidneys to similar degrees of haemodynamic stress induced by exercise.
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14. |
- Torffvit, Ole, et al.
(author)
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Albuminuria and associated medical risk factors: a cross-sectional study in 451 type II (noninsulin-dependent) diabetic patients. Part 2
- 1991
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In: Journal of Diabetic Complications. - 0891-6632. ; 5:1, s. 29-34
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Journal article (peer-reviewed)abstract
- The association between urinary albumin concentration (UAC) in a morning urine sample and medical risk factors was evaluated in a cross-sectional study of 451 type II (noninsulin-dependent) diabetic patients. The following four groups of patients were created according to their urinary albumin levels: A) normal (less than 12.5 mg/L); B) high normal (12.5-30 mg/L); C) microalbuminuria, ie, incipient nephropathy (31-299 mg/L); and D) clinical nephropathy (greater than or equal to 300 mg/L). The patients with high normal levels had higher HbA1c and systolic blood pressure levels than patients with values within normal limits. The prevalence of incipient and clinical diabetic nephropathy was 20 and 7%, respectively. Incipient nephropathy was associated with higher blood pressures and body weights. Patients with clinical nephropathy had even further increases in these parameters, were older, and had longer duration of diabetes. In both groups of nephropathy, men were preponderant. Thirty six percent of all patients and 73% of patients with clinical nephropathy were treated for hypertension; 55% were treated with insulin. The insulin-treated patients had poorer metabolic control, but there were no differences in blood pressure or serum creatinine levels as compared with those of patients not receiving insulin treatment. The proportion of patients with severe retinopathy increased with the degree of albuminuria, although 22% of the patients with clinical nephropathy continued to be nonretinopathic.
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15. |
- Torffvit, Ole, et al.
(author)
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Albuminuria and associated medical risk factors: a cross-sectional study in 476 type I (insulin-dependent) diabetic patients. Part 1
- 1991
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In: Journal of Diabetic Complications. - 0891-6632. ; 5:1, s. 23-28
-
Journal article (peer-reviewed)abstract
- Albumin concentration in a morning urine sample was analyzed in a cross-sectional study in 476 insulin-dependent diabetic patients. The following groups of patients were defined: A) normal urinary albumin (urine albumin less than 12.5 mg/L); B) high normal albuminuria (12.5-30 mg/L); C) microalbuminuria, ie, incipient nephropathy (31-299 mg/L); and D) clinical nephropathy (greater than or equal to 300 mg/L). The prevalences of incipient and clinical diabetic nephropathy were 24.8 and 14.4%, respectively. There were no differences in clinical parameters such as age, age at onset or duration of diabetes, blood pressure, serum creatinine, or HbA1c levels between groups A and B. The frequency of retinopathy in these groups was 55 and 50%, respectively. In group C, there were increases in age, duration of diabetes, blood pressure, serum creatinine, and HbA1c levels. The frequency of retinopathy was higher (80%), and more patients had severe forms (47%). In group D, there were further increases in all parameters and, in addition, younger age at onset of diabetes. The frequency of retinopathy was 97%, and severe forms of retinopathy were more common (86%). Seventeen percent of the patients were treated for hypertension. These patients were older, had longer duration of diabetes, and had higher levels of blood pressure, serum creatinine, and urinary albumin, as well as a younger age at onset of diabetes than patients not requiring antihypertensive treatment.
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16. |
- Torffvit, Ole, et al.
(author)
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Day and night variation in ambulatory blood pressure in type 1 diabetes mellitus with nephropathy and autonomic neuropathy
- 1993
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In: Journal of Internal Medicine. - 1365-2796. ; 233:2, s. 131-137
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Journal article (peer-reviewed)abstract
- The objective was to study ambulatory blood pressure and heart rate variability between day and night in patients with type 1 (insulin-dependent) diabetes mellitus with different degrees of diabetic nephropathy, and to evaluate the influence of autonomic neuropathy and type of antihypertensive treatment. Twenty type 1 diabetic patients with diabetic nephropathy and antihypertensive treatment were studied with 24-h ambulatory blood pressure monitoring using an oscillometric method. They were compared with eight insulin-treated diabetic patients with short duration of diabetes (1-5 years) and with 10 apparently healthy subjects. The degree of autonomic neuropathy was evaluated by measuring the RR-interval during deep breathing and uprising. The 24-h blood pressure was generally higher in patients with diabetic nephropathy compared to those other two groups. These patients also had a lower ratio between day and night in diastolic blood pressure compared to the control subjects (1.15 +/- 0.12 vs. 1.25 +/- 0.76, P < 0.05) and heart rate compared to the diabetic patients without nephropathy, as well as the control subjects (1.15 +/- 0.08 vs. 1.26 +/- 0.09 vs. 1.27 +/- 0.08, P < 0.01, respectively). All patients with diabetic nephropathy had clinical signs of autonomic neuropathy as judged by RR-interval measurements during deep breathing and uprising.
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17. |
- Torffvit, Ole, et al.
(author)
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Tubular secretion of Tamm-Horsfall protein is decreased in type 1 (insulin-dependent) diabetic patients with diabetic nephropathy
- 1993
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In: Nephron. - 0028-2766. ; 65:2, s. 227-231
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Journal article (peer-reviewed)abstract
- Signs of glomerular, proximal and distal tubular dysfunction as well as metabolic control were studied in type 1 diabetes mellitus. To that end, the urinary excretion rates of albumin, sodium, phosphate and Tamm-Horsfall protein as well as HbA1c levels were measured in 20 patients with different degrees of diabetic nephropathy (positive Albustix for several years). Eight diabetic patients with short duration of diabetes and without any diabetic complications and 10 apparently healthy subjects were studied for comparison. The HbA1c levels in the three groups were 8.6 +/- 1.2, 5.9 +/- 2.2 and 4.1 +/- 0.4%, respectively (mean +/- SD). Duration of diabetes in the two diabetic groups were 27 +/- 7 and 3 +/- 1 years, respectively. The urinary protein levels were measured by enzyme-linked immunoassays. The fractional clearance of sodium (1.9 +/- 1.9%; p < 0.001) and phosphate (27 +/- 11%; p < 0.01) were increased in patients with diabetic nephropathy compared to diabetic patients without nephropathy (0.6 +/- 0.2 and 16 +/- 4%) and healthy control subjects (0.6 +/- 0.1 and 16 +/- 4%, respectively). Tamm-Horsfall protein excretion rate was decreased in both diabetic groups (15.0x/3.1 and 37.9x/1.9 micrograms/min, geometric mean x/tolerance factor, p < 0.001 and p < 0.05, respectively) compared to the healthy subjects (63.8x/1.3 micrograms/min). Furthermore, patients with diabetic nephropathy had a lower excretion rate of Tamm-Horsfall protein (15.0x/3.1 micrograms/min) compared to patients without signs of nephropathy (37.9x/1.9 micrograms/min, p < 0.05).(ABSTRACT TRUNCATED AT 250 WORDS)
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18. |
- Almegard, B, et al.
(author)
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Outflow facility in the monkey eye: effects of calcitonin gene-related peptide, cholecystokinin, galanin, substance P and capsaicin
- 1990
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In: Experimental Eye Research. - 0014-4835. ; 51:6, s. 685-689
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Journal article (peer-reviewed)abstract
- A study in cats has shown that intracameral injection of calcitonin gene-related peptide (CGRP) increases the outflow facility by four- to fivefold concomitant with a decrease in intra-ocular pressure (IOP). Since there are great differences in the anatomy of the aqueous outflow routes between cats and primates, we have examined the effects of CGRP in the cynomolgus monkey. The possible influence of the sensory neuropeptides cholecystokinin (CCK), galanin and substance P on the outflow facility and IOP were also investigated. Determinations were performed using a two-level constant-pressure procedure. At 40–60 min after intracameral injection of 3 μg CGRP the outflow facility was increased from 0·68±0·11 to 1·03±0·15 μl min−1 mmHg−1 in the CGRP-treated eyes, and from 0·71±0·12 to 0·79±0·10 μl min−1 mmHg−1 in the control eyes. The mean difference in increase was 0·27±0·06 μl min−1 mmHg−1 (P < 0·01, N = 7). During the experiments there was a small rise in the IOP. CGRP at a dose of 3 μg caused a small rise in aqueous humor protein concentration. An attempt to release endogenous CGRP with capsaicin did not result in an increased outflow facility. Three micrograms each of CCK, galanin and substance P had no significant effect on either the outflow facility or the IOP. A miosis was observed in the experiments with CCK in agreement with previous findings. CCK seems thus to cause contraction of the pupillary sphincter but does not influence the ciliary muscle sufficiently to cause a facility effect in the monkey eye. Our results indicate that the effect of CGRP on the outflow facility in the monkey eye is much smaller than in cats, and that the other sensory neuropeptides tested have no clear effects on the conductance of the outflow routes.
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19. |
- Bill, A, et al.
(author)
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Cholecystokinin causes contraction of the pupillary sphincter in monkeys but not in cats, rabbits, rats and guinea-pigs: antagonism by lorglumide
- 1990
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In: Acta Physiologica Scandinavica. - 0001-6772. ; 138:4, s. 479-485
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Journal article (peer-reviewed)abstract
- The effects of intracameral injections of cholecystokinin (CCK) on the pupil size were determined in monkeys, cats, rabbits, rats and guinea-pigs. In animals under muscarinic cholinergic blockade, CCK caused miosis in monkeys but not in the other species investigated. In monkeys CCK-8 was more potent than CCK-33, which was, however, much more potent than non-sulphated CCK-8. These observations indicate that peripheral type A receptors mediated the miotic response. The effect of CCK-8 was not appreciably influenced by pretreatment with indomethacin, 3 mg kg-1 body wt, indicating that prostaglandins were not involved in the response. Nerve blockade with 0.9 micrograms tetrodotoxin intracamerally had no clear effect on the dose-response relationship for CCK-8. The effect of the peptide thus seems to be directly on receptors on the pupillary sphincter muscle. Pretreatment with lorglumide caused a dose-dependent rightward shift of the dose-response curve, indicating competitive antagonism. The results indicate that in monkeys, but not in rabbit, cats, rats and guinea-pigs, CCK is a potent miotic with a direct effect on the pupillary sphincter mediated by type A CCK receptors on the muscle.
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20. |
- Heldin, Carl-Henrik, et al.
(author)
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Platelet-derived growth factor B type receptor
- 1990
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In: Receptor Purification : Volume 1. Receptors for CNS Agents, Growth Factors, Hormones, and Related Substances - Volume 1. Receptors for CNS Agents, Growth Factors, Hormones, and Related Substances. - Totowa, NJ : Humana Press. - 9780896031678 - 9781461267713 - 9781461204619 ; 1, s. 303-314
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Book chapter (peer-reviewed)
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