Hypertension and nephrology

[Multi-photon fluorescence microscopy in the revealance of kidney physiology]

PRÓKAI Ágnes, BERTA Nóra, VANNAY Ádám, SZIKSZ Erna, KIS-PETIK Katalin, FEKETE Andrea, TOMA Ildikó, TULASSAY Tivadar, KELLERMAYER Miklós, PETI-PETERDI János, SZABÓ J. Attila

FEBRUARY 20, 2012

Hypertension and nephrology - 2012;16(01)

[In this review we discuss the importance of the multi-photon fluorescence microscopy in the relevance of kidney physiology. Most functions of the kidney, including the clearance of metabolic waste products, maintenance of body fluid, electrolyte homeostasis and blood pressure are achieved by complex interactions between multiple renal cell types and previously inaccessible structures that have been difficult to study. Multi-photon fluorescence microscopy offers an advanced imaging technique for deep optical sectioning of living tissues and organs with minimal deleterious effects. Dynamic regulatory processes and multiple functions in the intact kidney can be quantitatively visualized in real time with submicron resolution. This article reviews the application of multi-photon imaging technology that provided the most complex, spatial and temporal portrayal of renal function, depicting as well as analyzing the components and mechanisms involved in renal (patho)physiology such as glomerular structure and function, tubular transport, tubular-vesicular interaction and the intrarenal renin-angiotensin system.]

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Hypertension and nephrology

[Chronotherapy of hypertension - individualized treatment according to the circadian blood pressure profile]

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Hypertension and nephrology

[Guidelines and clinical practice: clinical audit of CKD-MBD in Hungarian dialyzed patients]

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[Patients suffering from chronic kidney disease reach the end-stage renal disease in ever growing numbers and this necessitates the start of their dialysis treatment. The alteration of bone and mineral metabolism together with the development of the consequent organ damages starts in early stages of the chronic kidney disease. The goal of our present trial was to survey the alterations or characteristics (laboratory results, concomitant diseases and treatment practice in Hungary) of the calcium (Ca) and phosphate (PO4) metabolisms [mineral-bone disorder occurring in chronic kidney disease (CKD-MBD) or formerly known as secunder hyperparathyreosis or renal ostedistrophy] in patients chronically treated with dialysis. We collected and analyzed data/results from 5334 chronically dialyzed patients. We categorized the patients into different groups according to the guidelines of CKD-MBD so basically by the level of serum calcium and parathormone (PTH) (se-Ca level is below or above 2.4 mmol/l; PHT level is below 65 pg/ml, between 65-150, 150-300, 300-500, 500-800 pg/ml or above 800 pg/ml) and then the characteristic variances were compared. The two most frequent primary causes of end-stage renal disease are hypertension (23%) and diabetes mellitus (22%). Serum calcium level was below the upper limit of the normal range (Ca <2.4 mmol/l) in the greatest proportion of our patients (n=4386), while the parathormone level was elevated (PTH >500 pg/ml) in large portion of patients (n=833). Likewise in a significant part of our patients (44.9%) the parathormone level was low (PTH <150 pg/ml). The concurrent pathological elevation of both the serum calcium and the parathormone levels was found in only a minority of the patients (n=150; 2.8%). All of the drugs influencing calcium-phosphate and parathormone levels were already accessible during the time of origin of the trial in Hungary, although the financial limitations significantly affected their prescription. This is one of the reasons why local treatment practice was not fully aligned with guidelines. On the other hand the application of native vitamin D had an especially low prevalence. To sum up, our results match the European practice on the whole, although we definitely need improvement in reaching the treatment targets and also the clinical treatment practice leading to it. We will prepare a proposal for further analysis and longterm extension of this trial.]

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