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Occurrence of anti-C1q antibodies in IgA nephropathy 总被引:1,自引:0,他引:1
Gunnarsson I; Ronnelid J; Lundberg I; Jacobson S 《Nephrology, dialysis, transplantation》1997,12(11):2263-2268
Background: The pathogenic mechanisms and the antigens
involved in the establishment and progress of IgA nephropathy are unknown.
As antibodies against C1q have been reported to correlate with SLE
nephritis, we analysed the occurrence of these antibodies in IgA
nephropathy in order to investigate the possibility of pathogenetic
similarities in these renal disorders. Methods: The
occurrence of IgA- and IgG anti-C1q antibodies (anti-C1q) were determined
by ELISA in patients with IgA nephropathy (n=36) and SLE nephritis (n=37),
diseases both known to be associated with circulating immune complexes.
Levels of these antibodies were also determined in two other glomerular
diseases, i.e. idiopathic membranous glomerulo-nephritis (n=7) and minimal
change disease (n=2), in which circulating immune complexes are usually not
present, and in 40 healthy controls. Results: IgA
anti-C1q was observed in increased titres in 11/36 of the patients with IgA
nephropathy, in 2/37 of the patients with SLE nephritis (both with
proliferative disease) and in 1/9 of the patients with membranous and
minimal change disease (P<0.001). Increased titres of IgG anti-C1q
were observed in 1/36 of the patients with IgA nephropathy, in 17/37 of the
patients with SLE nephritis and in 0/9 of the patients with membranous and
minimal change disease (P<0.001). There were no correlations between
the levels of anti-C1q antibodies and clinical parameters such as degree of
proteinuria, haematuria, or renal function. Nor was there any correlation
to the concentration of C3a and the terminal complement complex (TCC) in
patients with IgA nephropathy. Conclusions: The
occurrence of anti-C1q antibodies in both IgA nephropathy and SLE
nephritis, albeit of different predominating isotypes, indicates the
possibility of a similar pathogenic mechanism involved in these renal
disorders. The occurrence of IgA anti-C1q antibodies in patients with IgA
nephropathy has to our knowledge not previously been reported. 相似文献
5.
G Lindstedt E Nystr?m P A Lundberg E Johansson R Eggertsen 《Scandinavian journal of primary health care》1992,10(3):192-197
In order to assess the diagnostic outcome of a screening for primary hyperparathyroidism (PHPT) in an elderly population, we determined ionized calcium in serum from 368 individuals participating in a health control at M?lnlycke Primary Care Centre (200 women, 168 men; age range 75-95 years); four-fifths of the individuals living in their homes, the remainder in homes for aged or nursing homes. Intact parathyroid hormone was determined in the samples with oinized calcium concentration greater than mean + 3SD of the truncated population sample, and these individuals were also recalled for another blood sample. Moderate hypercalcaemia, probably due to PHPT, was found in eight individuals (2% of the complete sample, 3% of the women), five having neuropsychiatric or neuromuscular symptoms consistent with PHPT. Surgical intervention is probably indicated in only a small proportion of elderly patients. We conclude that optimal benefits in relation to costs of screening for PHPT in old people will depend on the availability of a safe and simple pharmacological treatment that could determine any causal relationship between hypercalcaemia and symptoms. 相似文献
6.
M Frankenhaeuser U Lundberg M Rauste von Wright J von Wright G Sedvall 《Pharmacology, biochemistry, and behavior》1986,24(6):1521-1525
Concentrations of the serotonin metabolite 5-hydroxyindole acetic acid (5-HIAA), the dopamine metabolite homovanillic acid (HVA) and the noradrenaline metabolite 4-hydroxy-3-methoxyphenyl glycol (HMPG) were determined in urine samples from healthy male and female students by mass fragmentography. Urine samples were obtained after a demanding examination (mental stress) and a day of ordinary school work (control condition). Self-ratings were obtained of feelings induced by the examination, and of habitual psychosomatic symptoms. The results for both sexes showed that the examination stress induced a significant increase of HVA and HMPG excretion, but not of 5-HIAA. The males excreted significantly more of each of the metabolites than the females. The pattern of correlations between metabolite levels and psychological and psychosomatic variables were strikingly different for the two sexes. 相似文献
7.
A. Rudehill J. M. Lundberg A. Sollevi P. Hjemdahl 《Acta anaesthesiologica Scandinavica》1987,31(2):132-138
Graded increases of intracranial pressure (ICP) in anaesthetized pigs induced elevations of plasma levels of neuropeptide Y (NPY)-like immunoreactivity (LI) and catecholamines, simultaneously with hypertension and tachycardia. Plasma adrenaline (ADR) increased at a lower ICP-level than did the plasma levels of noradrenaline (NA) and NPY-LI. At the maximal ICP elevation, 22.9 kPa (172 mmHg), plasma NPY-LI was increased about 10-fold, from 48 +/- 8 pmol/l in the basal state, while NA and ADR concentrations increased more than 100-fold. At this maximal ICP-level the plasma levels of NPY-LI were correlated to the concentrations of both NA (r = 0.87, P less than 0.01) and ADR (r = 0.92, P less than 0.001). Plasma NPY-LI continued to increase to about 1000 pmol/l, 10 min after the maximal elevation of ICP was discontinued, while the catecholamines then had declined considerably. A slight cardiac release of NPY-LI was observed at the maximal elevation of ICP. The half-life of NPY-LI in plasma was about 6 min upon systemic infusion. At plasma levels similar to those obtained upon maximal ICP elevation, exogenous NPY caused slight vasoconstriction in the spleen and skeletal muscle, but had no effects on coronary blood flow or systemic blood pressure. This suggests that NPY mainly exerts local actions after release from nerve endings, while levels of circulating NPY in plasma must be very high to influence blood flow in some organs. It is concluded that elevation of ICP results in hypertension and tachycardia related to elevated plasma levels of NPY-LI and catecholamines.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
8.
Digital radiography of subtle pulmonary abnormalities: an ROC study of the effect of pixel size on observer performance 总被引:3,自引:0,他引:3
Forty conventional radiographs with examples of mild interstitial infiltrates and subtle pneumothoraces and 40 normal studies of the chest were selected and digitized, with pixel sizes of 1.0, 0.5, 0.2, and 0.1 mm. Observer performance tests were carried out using receiver operating characteristic analysis. Conventional radiographs and digitized images were compared. The results indicate that, in such cases, diagnostic accuracy increases significantly as the pixel size is reduced, at least to the 0.1-mm level. We conclude that, for digital systems using screen-film or similar image receptors, use of a pixel size substantially larger than 0.1 mm may result in some loss of diagnostic accuracy. 相似文献
9.
Summary The cerebral changes are described in a woman of 54 who suffered from Binswanger's encephalopathy: there were no signs or symptoms of chronic arterial hypertension. The disease presented as dementia of about 3 years duration. Computed tomography of the brain 2. 5 years before her death showed bilateral widespread hypodense lesions in the cerebral white matter. She died of an asthmatic attack. Autopsy disclosed extensive bilateral degeneration of the central white matter, lacunes and gliosis. Severe obliterative arteriolosclerosis occurred in the meningeal vessels and those supplying the affected parts of the brain. Light microscopy showed that the most severe lesions occurred in the arterioles. Immunohistochemistry demonstrated profound extravasation of plasma proteins chiefly albumin, indicating dysfunction of the blood-brain barrier. Thus, the lesions characteristic of Binswanger's encephalopathy may develop in the absence of chronic arterial hypertension. Additional pathogenic factors, possibly genetic predisposition to vascular injury may play a role in the development of this condition.Supported by grants from the Swedish Medical Research Council, Project No 12X-03020 and 1987 Års Stiftelse för Strokeforskning 相似文献
10.
PL Macken FRACO FRACS CJ Pavlin FRCS R Tuli MD GE Trope PhD FRCS 《Clinical & experimental ophthalmology》1995,23(3):217-220
Background: Spherophakia is an uncommon diagnosis. This is the first case report of spherophakia evaluated by ultrasound biomicroscopy.
Methods: Ultrasound biomicroscopy is a new diagnostic technique developed by one of the authors and provides images with microscopic resolution of the anterior segment. A patient with spherophakia was evaluated by ultrasound biomicroscopy (Zeiss-Humphrey, 50MHz) before and after YAG laser iridotomy.
Results: Ultrasound biomicroscopic assessment revealed a shallow anterior chamber, a very steep anterior lens curvature, iridolenticular contact, elongated zonules, and an increased distance between the lens equator and the ciliary processes. Angle closure glaucoma was due to a pupil block mechanism. The pupil block was relieved by YAG laser iridotomy.
Conclusions: Ultrasound biomicroscopy is a useful technique to confirm the diagnosis of spherophakia. The pupil block in spherophakia is relieved by YAG laser iridotomy. 相似文献
Methods: Ultrasound biomicroscopy is a new diagnostic technique developed by one of the authors and provides images with microscopic resolution of the anterior segment. A patient with spherophakia was evaluated by ultrasound biomicroscopy (Zeiss-Humphrey, 50MHz) before and after YAG laser iridotomy.
Results: Ultrasound biomicroscopic assessment revealed a shallow anterior chamber, a very steep anterior lens curvature, iridolenticular contact, elongated zonules, and an increased distance between the lens equator and the ciliary processes. Angle closure glaucoma was due to a pupil block mechanism. The pupil block was relieved by YAG laser iridotomy.
Conclusions: Ultrasound biomicroscopy is a useful technique to confirm the diagnosis of spherophakia. The pupil block in spherophakia is relieved by YAG laser iridotomy. 相似文献