Potential role of IGF-1 in parathyroid hormone-related renal growth induced by high protein diet in uninephrectomized rats

Potential role of IGF-1 in parathyroid hormone-related renal growth induced by high protein diet in uninephrectomized rats. Recent studies indicate that parathyroidectomy (PTX) prevents the progression of kidney damage due to high protein diet in the subtotal nephrectomized rat model of chronic renal failure. Associated with this protection, the difference in the renal “compensatory” growth induced by high (HPr) as compared to normal protein diet (NPr) is completely abolished by PTX. To understand the physiological mechanism responsible for this protection, the changes in both circulating level and kidney content of IGF-1, a growth factor capable of influencing renal “compensatory” growth, was analyzed after unilateral nephrectomy (UNX). In UNX rats, HPr as compared to NPr diet given for five days significantly increased the kidney/body weight ratio (0.48 ± 0.01%, N = 11 vs. 0.44 ± 0.01%, N = 11, P < 0.005) and the plasma level of IGF-1 (365 ± 10 ng/ml vs. 306 ± 10 ng/ml, P < 0.001). In UNX rats fed HPr, PTX completely abolished the renal “compensatory” growth (0.38 ± 0.02%, N = 7, P < 0.001) and the increased plasma level of IGF-1 (246 ± 14 ng/ml, N=7,P < 0.001). In PTX-UNX rats treated with physiological doses of 1,25-dihydroxyvitamin D3 which nearly normalized the calcemia, the renal growth and the increased plasma level of IGF-1 induced by HPr were restored towards those recorded in SHAM-UNX rats fed the HPr diet. Similar effects were observed in PTX-UNX rats in which the plasma calcium concentration was increased by the chronic administration of a retinoid derivative, used as an agent where the calcemie effect is essentially mediated by a stimulation of bone resorption. There was a positive significant correlation between the change in kidney growth in response to UNX and the plasma level of IGF-1 (r = 0.685, P < 0.001). The kidney IGF-1 content was affected neither by the protein intake nor by the PTH status. In rats with an intact renal mass and fed NPr diet, chronic administration of bovine PTH did not alter the plasma IGF-1 concentration. In these animals, both the increase of the plasma IGF-1 level under HPr diet and the blunting effect of PTX thereon were similar to the response observed in UNX animals. There was, however, no significant change in the kidney/body weight ratios in response to HPr diet. In conclusion, the results of the present study provide evidence that calciotropic hormones such as PTH and 1,25-dihydroxyvitamin D3 and/or the associated change in extracellular calcium concentration modulate the effect of protein intake on hepatic production of IGF-1. In rats with a reduced renal mass, the elevation in the circulating level of IGF-1 is likely responsible for the increased “compensatory” growth of remaining nephrons, which is associated with an acceleration of renal function deterioration induced by high protein diet

Cause Specific Mortality in Japan: Contour Maps Approach

An important part of the activity of IIASA's Population Program is related to the development of data visualization techniques. The paper is devoted to the analysis of cause specific mortality data for Japan using the shaded contour map approach which was recently developed in the program by an international team of scientists

Ten Years» Experience of Aortic Aneurysm Associated with Systemic Lupus Erythematosus

AbstractBackground: aortic aneurysm is a rare but life-threatening cardiovascular complication in patients with systemic lupus erythematosus (SLE). The purpose of this study was to clarify the characteristic clinical features and the pathological mechanism of aneurysmal formation in these patients. Methods: among 429 patients operated on for abdominal aortic aneurysm (AAA) during the past 10 years, five cases with SLE were treated surgically. Their clinical data were reviewed, and the resected aneurysmal wall of the five patients was also examined histologically. Results: the mean age of the patients with SLE was 55 years, which was statistically younger than that of the other patients (mean 77 years, s.d. 7.9, p <0.05). They had received long-term corticosteroid therapy for the treatment of SLE for a mean of 23 years. Histologically, destruction of the medial elastic lamina was characteristic. Four patients had no complications in the postoperative follow-up period (mean 4 years), while the remaining patient died of rupture of a dissecting aneurysm two years after operation.Conclusion : prolonged steroid therapy may play a major role in accelerating atherosclerosis, which can result in aortic aneurysmal enlargement, possibly together with primary aortic wall involvement and/or vasculitic damage in patients with SLE

SATB1 (SATB homeobox 1)

Review on SATB1 (SATB homeobox 1), with data on DNA, on the protein encoded, and where the gene is implicated

In vitro transcription of compound heterozygous hypofibrinogenemia Matsumoto IX; first identification of FGB IVS6 deletion of 4 nucleotides and FGG IVS3-2A > G causing abnormal RNA splicing

ArticleClinica Chimica Acta. 411(17-18):1325-1329 (2010)journal articl

Landau Model for Commensurate-Commensurate Phase Transitions in Uniaxial Improper Ferroelectric Crystals

We propose the Landau model for lock-in phase transitions in uniaxially modulated improper ferroelectric incommensurate-commensurate systems of class I. It includes Umklapp terms of third and fourth order and secondary order parameter representing the local polarization. The corresponding phase diagram has the structure of harmless staircase, with the allowed wave numbers obeying the Farey tree algorithm. Among the stable commensurate phases only those with periods equal to odd number of lattice constants have finite macroscopic polarizations. These results are in excellent agreement with experimental findings in some A2BX4 compounds.Comment: 9 pages, 5 figures, revtex, to be published in Journal of Physics: Cond. Matter as a Letter to the Edito

Continued-fraction expansion of eigenvalues of generalized evolution operators in terms of periodic orbits

A new expansion scheme to evaluate the eigenvalues of the generalized evolution operator (Frobenius-Perron operator) $H_{q}$ relevant to the fluctuation spectrum and poles of the order-$q$ power spectrum is proposed. The ``partition function'' is computed in terms of unstable periodic orbits and then used in a finite pole approximation of the continued fraction expansion for the evolution operator. A solvable example is presented and the approximate and exact results are compared; good agreement is found.Comment: CYCLER Paper 93mar00