Hypertension in children with chronic kidney disease: pathophysiology and management

Arterial hypertension is very common in children with all stages of chronic kidney disease (CKD). While fluid overload and activation of the renin–angiotensin system have long been recognized as crucial pathophysiological pathways, sympathetic hyperactivation, endothelial dysfunction and chronic hyperparathyroidism have more recently been identified as important factors contributing to CKD-associated hypertension. Moreover, several drugs commonly administered in CKD, such as erythropoietin, glucocorticoids and cyclosporine A, independently raise blood pressure in a dose-dependent fashion. Because of the deleterious consequences of hypertension on the progression of renal disease and cardiovascular outcomes, an active screening approach should be adapted in patients with all stages of CKD. Before one starts antihypertensive treatment, non-pharmacological options should be explored. In hemodialysis patients a low salt diet, low dialysate sodium and stricter dialysis towards dry weight can often achieve adequate blood pressure control. Angiotensin-converting enzyme (ACE) inhibitors and angiotensin receptor blockers are first-line therapy for patients with proteinuria, due to their additional anti-proteinuric properties. Diuretics are a useful alternative for non-proteinuric patients or as an add-on to renin–angiotensin system blockade. Multiple drug therapy is often needed to maintain blood pressure below the 90th percentile target, but adequate blood pressure control is essential for better renal and cardiovascular long-term outcomes

Therapeutic strategies to slow chronic kidney disease progression

Childhood chronic kidney disease commonly progresses toward end-stage renal failure, largely independent of the underlying disorder, once a critical impairment of renal function has occurred. Hypertension and proteinuria are the most important independent risk factors for renal disease progression. Therefore, current therapeutic strategies to prevent progression aim at controlling blood pressure and reducing urinary protein excretion. Renin-angiotensin-system (RAS) antagonists preserve kidney function not only by lowering blood pressure but also by their antiproteinuric, antifibrotic, and anti-inflammatory properties. Intensified blood pressure control, probably aiming for a target blood pressure below the 75th percentile, may exert additional renoprotective effects. Other factors contributing in a multifactorial manner to renal disease progression include dyslipidemia, anemia, and disorders of mineral metabolism. Measures to preserve renal function should therefore also comprise the maintenance of hemoglobin, serum lipid, and calcium-phosphorus ion product levels in the normal range

Involvement of glomerular renin−angiotensin system (RAS) activation in the development and progression of glomerular injury

Recently, there has been a paradigm shift away from an emphasis on the role of the endocrine (circulating) renin−angiotensin system (RAS) in the regulation of the sodium and extracellular fluid balance, blood pressure, and the pathophysiology of hypertensive organ damage toward a focus on the role of tissue RAS found in many organs, including kidney. A tissue RAS implies that RAS components necessary for the production of angiotensin II (Ang II) reside within the tissue and its production is regulated within the tissue, independent of the circulating RAS. Locally produced Ang II plays a role in many physiological and pathophysiological processes such as hypertension, inflammation, oxidative stress, and tissue fibrosis. Both glomerular and tubular compartments of the kidney have the characteristics of a tissue RAS. The purpose of this article is to review the recent advances in tissue RAS research with a particular focus on the role of the glomerular RAS in the progression of renal disease

Therapeutic approach to FSGS in children

Therapy of primary focal segmental glomerulosclerosis (FSGS) in children incorporates conservative management and immunosuppression regimens to control proteinuria and preserve kidney function. In long-term cohort studies in adults and children with primary FSGS, renal survival has been directly associated with degree of proteinuria control. This educational article reviews the current therapeutic approach toward children with primary FSGS

Tunnelspektroskopie an Supraleitern unter extremen Bedingungen Amorphe Metalle, Lanthan unter Druck, Palladium-Wasserstoff

Die Tunnelspektroskopie hat sich in den letzten Jahren als informativste Methode zur Untersuchung der Supraleitung erwiesen. Aus Messungen der Leitfähigkeit einer Tunneldiode können die wesentlischen Eigenschaften eines Supraleiters erschlossen werden. Man erhält die Eliashberg-Funktion $\alpha^{2}F(\omega)$, der eine zentrale Rolle in der Supraleitung zukommt. Aus dieser Funktion sind alle thermodynamischen Eigenschaften des Supraleiters berechenbar. Tunnelexperimente bestätigten hierbei in überzeugender Weise die Bedeutung der Elektron-Phonon-Wechselwirkung für die Supraleitung. Sie zeigten weiterhin, daß die Theorie für starke Elektron-Phonen-Wechselwirkung die Supraleitung exakt beschreibt. [...

TUNNELLING EXPERIMENTS ON Cu1.8Mo6S8

L'énergie du gap Ɗ0 et des structures dans la densité d'état tunnel dues aux phonons ont été mesurées pour Cu1.8Mo6S8 à l'aide de contacts à pointe. Le rapport 2Ɗ0/kTc exède 4,0, ce qui indique un fort couplage électron-phonon. Suivant nos résultats de dérivée seconde, les vibrations optiques des atomes de Cu à basses énergie contribuent à la supraconductivité.The energy gap Ɗ0. and phonon-induced structures in the tunnelling density of states have been measured for Cu1.8Mo6S8, using point contacts. The ratio 2Ɗ0/kTc exceeds 4.0, indicating strong electron-phonon coupling. From our second derivative data we infer that the low lying optic vibrations of the Cu atoms contribute to superconductivity