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  • Author or Editor: A. Peti x
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The population in the Western world is aging. In 1996 those aged 60 years and over formed 21% of the EU population, by 2022 this proportion will have risen to 27%. Based on current trends a third of the EU population could be 60 years of age and over by the age 2050.Epidemiological studies suggest that even in the absence of other risk factors (e.g. diabetes, hypertension, hypercholesterolemia), advanced age itself significantly increases cardiovascular morbidity by promoting the development of atherosclerosis and by impairing normal cellular functions. One of the most prominent organs affected by aging is the kidney. There is evidence that age-associated phenotypic changes may be an important cause of renal failure. We propose that vascular oxidative stress and inflammation are generalized phenomena during senescence, which importantly contribute to the morphological and functional changes in the aging kidney. The present review focuses on some of the mechanisms by which advanced age may promote vascular oxidative and nitrosative stress and the possible downstream mechanisms by which reactive oxygen and nitrogen species may impair vascular and renal function in aging.

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Authors: L. Rosivall, J. Peti-Peterdi, Zs. Rázga, A. Fintha, Cs. Bodor and S. MirzaHosseini

The afferent arteriole (AA) is an important regulatory site of renal function and blood pressure. We have demonstrated endothelial fenestration and high permeability in the vicinity of renin granulated epithelioid cells in the juxtaglomerular portion of the afferent arteriole in different mammals. The permeability of fenestrated endothelium of afferent arteriole may be important in connection to various physiologic and pathophysiologic processes. We have assumed that the permeable fenestration may serve as a communication channel between the intravascular circulation and a pathway for renin secretion. Utilising the multiphoton image technique we were able to visualise the endothelial fenestration and renin granules of the in vitro microperfused AA and in vivo AA. We demonstrated that ferritin-positive, i.e., permeable portion of the afferent arteriole, under control conditions is on average 45 μm, which is about one-third to half of the total length of the afferent arteriole. The length of this portion is not constant and can change by physiologic and pharmacologic manipulation of renin formation. The permeability of the afferent arteriole is not changing only parallel with the pharmacologically stimulated renin secretion as already demonstrated in adult rats, but also with the change of renin appearance in afferent arteriole within the very first few days of life after birth. Independently from the age there is a significant correlation between the renin-positive and permeable portion of the AA. Further studies are necessary to clarify the physiological significance of afferent arteriolar permeability and its changes in the postnatal development of the kidney, as well as in correlation with activity of renin- angiotensin system.

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Authors: B. Sági, A. Peti, O. Lakatos, T. Gyimesi, E. Sulyok, I. Wittmann and Botond Csiky

Abstract

Objective

In this observational study we addressed accelerated arteriosclerosis (AS) in patients with chronic renal failure (CRF) on hemodialysis (HD) by measuring vascular stiffness (VS) parameters and attempted to relate them to pro-inflammatory and protective factors.

Patients

96 consecutive patients receiving regular HD were included. 20 adult patients without major renal, cardiovascular or metabolic morbidities served as controls.

Methods

AS parameters (carotid-femoral pulse wave velocity – PWV, aortic augmentation index – Aix) were measured by using applanation tonometry (SphygmoCor, AtCor Medical, Sidney). In addition to routine laboratory tests 25(OH) vitamin D3 (vitamin D3) and high-sensitivity C-reactive protein (hsCRP) were quantified by immunometric assay; whereas fetuin-A, α-Klotho, tumor necrosis factor-α (TNF-α) and transforming growth factor-β1 (TGF-β1) were determined by ELISA.

Results

Pro-inflammatory biomarkers (hsCRP, TNF-α and TGF-β1) were markedly elevated (P < 0.01), while anti-inflammatory factors (fetuin-A: P < 0.05, α-Klotho: P < 0.01, vitamin D3: P < 0.01) significantly depressed in HD patients when compared to controls. PWV was significantly affected only by total cholesterol, fetuin-A and dialysis time. Multiple linear regression analyses revealed that several clinical and laboratory parameters were associated with pro- and anti-inflammatory biomarkers rather than VS. The impact of baseline clinical and biochemical variables on outcome measures were also analyzed after three-year follow-up, and it was demonstrated that low levels of vitamin D, α-Klotho protein and fetuin-A were related to adverse cardiovascular outcomes, whereas all-cause mortality was associated with elevated hsCRP and depressed vitamin D.

Conclusions

Our results provide additional information on the pathomechanism of accelerated AS in patients with CRF, and documented direct influence of pro- and anti-inflammatory biomarkers on major outcome measures.

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Authors: P. Török, E. Tóth, K. Tóth, O. Valkó, B. Deák, B. Kelbert, P. Bálint, Sz. Radócz, A. Kelemen, J. Sonkoly, T. Miglécz, G. Matus, A. Takács, V. A. Molnár, K. Süveges, L. Papp, L. Papp Jr., Z. Tóth, B. Baktay, G. Málnási Csizmadia, I. Oláh, E. Peti, J. Schellenberger, O. Szalkovszki, R. Kiss and B. TÓthmérész

For understanding local and regional seed dispersal and plant establishment processes and for considering the ecotypes and other forms of specific variability, hard data of locally or regionally measured traits are necessary. We provided newly measured seed weight data of 193 taxa, out of which 24 taxa had not been represented in the SID, LEDA or BiolFlor databases. Our new measurements and formerly published data of locally collected seed weight records together covers over 70% of the Pannonian flora. However, there is still a considerable lack in seed weight data of taxonomically problematic genera, even though they are represented in the Pannonian flora with a relatively high number of species and/or subspecies (e.g. Sorbus, Rosa, Rubus, Crataegus and Hieracium). Our regional database contains very sporadic data on aquatic plants (including also numerous invasive species reported from Hungary and neighbouring countries) and some rare weeds distributed in the southwestern part of the country. These facts indicate the necessity of further seed collection and measurements.

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