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J Asplund

Publications and source records attributed to J Asplund.

At least 19 recordsLinked to original sources
PubMed1999

Neovascularization at the vascular pole region in diabetic glomerulopathy.

BACKGROUND: Diabetic nephropathy is associated with renal structural changes involving all of the compartments. Most characteristic is the diabetic glomerulopathy. Studies of the histological changes during the early phases of nephropathy have included the glomerulopathy and also the juxtaglomerular structures. Neovascularization, well-known in diabetic retinopathy, has also been observed in the kidney. The present study concerns estimates of frequency of neovascularization at the vascular pole region in early stages of diabetic nephropathy. METHODS: Extra efferent arterioles at the glomerular vascular pole were detected during measurements of the vascular pole area applying 1-microm serial sections through kidney biopsies. It was observed that more than one efferent arteriole existed occasionally. The present study was carried out with the aim of estimating the frequency of this phenomenon in diabetic patients and in non-diabetic controls, the diabetic patients categorized according to the level of albumin excretion rate. RESULTS: Neovascularization was first observed in IDDM patients with microalbuminuria. Some of the cases presented the phenomenon in all of the glomeruli studied. As the examinations of many kidney biopsies continued the phenomenon was observed also in the non-diabetic control group and in one IDDM patient with normoalbuminuria. However, the frequency was statistically highly significantly increased in patients with elevated albumin-excretion. Within this group a strong correlation between frequency of neovascularization and the severity of diabetic glomerulopathy is seen. CONCLUSIONS: The vascular abnormality localized to the vascular pole region is observed occasionally in the normal kidney, but the frequency is increased in patients with diabetic glomerulopathy. The abnormality may develop as a consequence of a long-standing diabetic glomerulopathy and might lead to less pronounced elevation of albumin excretion.

Adolescent↗
PubMed1998

Level of heteroplasmy for the mitochondrial mutation A3243G correlates with age at onset of diabetes and deafness.

The mitochondrial mutation A3243G has been shown to be associated with a syndrome of diabetes mellitus and sensorineural hearing loss. Using a solid-phase-based sequencing method we have investigated the relation between the proportion of mutant mitochondrial genomes and the time of disease onset among members of three families where the mutation segregates. A striking association was observed between the level of heteroplasmy and time of onset of disease, particularly hearing loss. Accordingly, this syndrome shares features of diseases caused by dynamic mutations in that variable transmission of the level of heteroplasmy between generations influences disease severity.

Adolescent↗
PubMed1998

Renal structural changes in insulin-dependent diabetic patients with albuminuria. Comparison of cases with onset of albuminuria after short or long duration.

The large interindividual variation in diabetes duration until the onset of nephropathy is partly unexplained. This study was performed to compare renal structure in insulin-dependent (IDDM) patients who had developed signs of nephropathy after a short or long duration of diabetes. Renal biopsies were obtained from 17 IDDM patients, with albumin excretion rate 20-300 microg/min and normal blood pressure. Six patients had <25 years duration ("short-term", early onset of microalbuminuria) and eight patients had duration >30 years ("long-term", late onset of microalbuminuria). Biopsies were obtained 18 months after entry into a study testing the effect of low-dose antihypertensives. Parameters characterizing diabetic glomerulopathy were significantly increased in IDDM patients compared with those in 17 living donors: Basement membrane thickness, mean and (CV): 591 nm (0.17) vs 320 nm (0.12), mesangial volume fraction per glomerulus 0.27 (0.19) vs 0.19 (0.10), matrix volume fraction per glomerulus 0.16 (0.20) vs 0.097 (0.22), matrix star volume 38.5 microm3 (0.43) vs 13.9 microm3 (0.31), (p<10(-4) for each). Comparison of short vs long-term patients showed no significant differences in glomerulopathy parameters, glomerular volume or extracellular material per glomerulus, whereas the fraction of occluded glomeruli was significantly increased in long-term patients. A close correlation obtained between fraction of occluded glomeruli and glomerular filtration rate (r=0.72, p= 0.001). Glomerular occlusion occurred unrelated to the severity of diabetic glomerulopathy. It is suggested that diabetic macroangiopathy and arteriolar hyalinization may play an important role in the renal function of patients with slow development of nephropathy.

Adult↗
PubMed1998

A clinical evaluation of long term retention with bonded retainers made from multi-strand wires.

The majority of patients from 4 orthodontic clinics in the south west of Sweden who have had bonded retainers on upper or lower anterior teeth for a period of at least 5 years were examined. The total failure rate during 5 years of observation was 36 per cent, slightly higher in the maxilla than in the mandible. The retainer had become detached in 15 per cent of the teeth bonded. The failure rate decreased during the 5 year period of observation. Seven fractures were reported, all in the upper front teeth. The failure rate was reduced when the retainers were positioned incisally, when larger diameter wires were used and in the 12 cases where a groove had been cut into the enamel to accept the retainer. The findings suggest that a limited flexibility of the retainer may be an advantage. In about 20 per cent of the retained segments minor rotations and small areas of space opened between some of the teeth attached to the retainer. No new caries lesions were found on any of the teeth associated with the bonded retainers during the period of observation.

Adolescent↗
PubMed1997

Glomerular volume and the glomerular vascular pole area in patients with insulin-dependent diabetes mellitus.

The vascular pole area (VPA) and glomerular volume were measured in renal biopsies from 9 insulin-dependent diabetes mellitus (IDDM) patients with normal albumin excretion rate (IDDM group 1), 38 IDDM patients with albumin excretion rate > 15 micrograms/min (IDDM group 2) and 10 living kidney donors (ND). The volume of individual glomeruli was estimated as the sum of profile areas factored by the measured distance between levels, t approximately 10 microns, and VPA as the sum of chords multiplied by t. Mean glomerular volume was increased in IDDM patients but reached statistical significance only in IDDM group 2 (P = 0.002 vs ND). VPA was significantly different among the groups, mean (CV%) was 2036 (29) microns2 in ND, 3555 (34) micron2 in IDDM group 1, and 3528 (48) microns2 in IDDM group 2, p = 0.004 and 0.001, IDDM versus ND. VPA calculated as a percentage of the surface area of the corresponding glomerulus was 2.4 (23)% in ND, 3.4 (27)% in IDDM group 1, and 3.3 (42)% in IDDM group 2; P = 0.007 and 0.01, IDDM versus ND. The intra-biopsy coefficient of variation was high (20-35%) and of the same order in all groups for all three measurements. Glomerular volume and absolute as well as relative size of VPA showed a positive correlation with estimates of mesangial expansion in IDDM group 2 and the VPA showed a negative correlation with GFR. Thus, part of the enlargement may represent a compensatory phenomenon triggered by the development of structural and functional abnormalities in the diabetic kidney.

Adolescent↗
PubMed1993

No pharmacokinetic effect of retaining the infusion site up to four days during continuous subcutaneous insulin infusion therapy.

This study was designed to investigate whether the indwelling time of the needle during continuous subcutaneous insulin infusion (CSII) could contribute to one of the main problems with subcutaneous insulin administration, that is the day-to-day intra-patient variation in absorption. The effect on insulin kinetics after a bolus dose was investigated at different time intervals up to 4 days after insertion of an indwelling catheter in situ for CSII therapy. Nine insulin-dependent diabetic patients treated with pump (Nordisk Infuser; Velosulin 100 U ml-1) took part in the study. The evening before day 1 of the investigation a needle connected to the pump with a polyethylene catheter was inserted subcutaneously on the abdominal wall where it remained throughout the investigation. There were no significant differences in blood glucose or plasma free insulin profiles between days 1, 3, and 5. The intra-patient coefficient of variation of free insulin was 38% at basal and 19% at post-bolus state. We conclude that during CSII it is acceptable from a pharmacokinetic point of view to retain the infusion site for up to 4 days.

Adult↗