Determination of fluid status in haemodialysis patients with whole body and calf bioimpedance techniques

Aim: The aim of this study was to demonstrate the ability of widely used bioimpedance techniques to assess dry weight (DW) and to predict a state of normal hydration in haemodialysis patients whose post-dialysis weight had been gradually reduced from baseline in successive treatments over time. Methods: Calf bioimpedance spectroscopy (cBIS) was employed to determine DW (DWcBIS) as defined by flattening of an intradialytic continuously measured resistance curve and by normalized resistivity (nRho) being in the gender-specific normal range. The wECV/ TBW ratio was determined by ` classical' wrist-to-ankle whole body bioimpedance spectroscopy (wBIS); in addition, a novel whole body model (WBM) based on wBIS was used to predict normal hydration weight (NHWWBM). Results: Twenty-one haemodialysis patients were studied; 11 1 6 measurements were performed per patient. Nine patients reached DWcBIS (DWcBIS group), while 12 patients remained fluid-overloaded (non-DWcBIS group). Change in wECV as measured by wBIS accounted for 46 1 23% in DWcBIS group, which was higher than in non-DWcBIS group (33 1 48%, P < 0.05) of actual weight loss at the end of study. In both groups the wECV/ TBW ratio did not change significantly between baseline and study end. Mean predicted NHWWBM at baseline was 3.55 1 1.6 kg higher than DWcBIS. The difference in DWcBIS and NHWWBM was 1.97 1 1.0 kg at study end. Conclusion: WBM could be useful to predict a target range of normal hydration weight particularly for patients with substantial fluid overload. The cBIS provides an accurate reference for the estimation of DW so that combined use of cBIS and WBM is promising and warrants further studies

Control of Core Temperature and Blood Pressure Stability during Hemodialysis

Background and objectives: Cool dialysate may ameliorate intradialytic hypotension (IDH). It is not known whether it is sufficient to prevent an increase in core temperature (CT) during hemodialysis (HD) or whether a mild decline in CT would yield superior results. The aim of this study was to compare both approaches with regard to IDH

Hypertension and renin-angiotensin system blockers are not associated with expression of angiotensin-converting enzyme 2 (ACE2) in the kidney

AIMS: Angiotensin-converting enzyme 2 (ACE2) is the cellular entry point for severe acute respiratory syndrome coronavirus (SARS-CoV-2)-the cause of coronavirus disease 2019 (COVID-19). However, the effect of renin-angiotensin system (RAS)-inhibition on ACE2 expression in human tissues of key relevance to blood pressure regulation and COVID-19 infection has not previously been reported. METHODS AND RESULTS: We examined how hypertension, its major metabolic co-phenotypes, and antihypertensive medications relate to ACE2 renal expression using information from up to 436 patients whose kidney transcriptomes were characterized by RNA-sequencing. We further validated some of the key observations in other human tissues and/or a controlled experimental model. Our data reveal increasing expression of ACE2 with age in both human lungs and the kidney. We show no association between renal expression of ACE2 and either hypertension or common types of RAS inhibiting drugs. We demonstrate that renal abundance of ACE2 is positively associated with a biochemical index of kidney function and show a strong enrichment for genes responsible for kidney health and disease in ACE2 co-expression analysis. CONCLUSION: Our results indicate that neither hypertension nor antihypertensive treatment is likely to alter the expression of the key entry receptor for SARS-CoV-2 in the human kidney. Our data further suggest that in the absence of SARS-CoV-2 infection, kidney ACE2 is most likely nephro-protective but the age-related increase in its expression within lungs and kidneys may be relevant to the risk of SARS-CoV-2 infection

Tissue engineering: new tools for old problems

More than 20 years have passed since Langer and Vacanti wrote the landmark paper defining the field of Tissue Engineering. In that paper, Tissue Engineering (TE) was described as a field having an interdisciplinary approach to create biological substitutes that would restore or enhance the function of tissues or organs [1]. At the time, the authors identified as critical points for the success of the field the issues of cell sourcing and of the materials used to engineer the substitutes. Since then, the field of Tissue Engineering has seen amazing advancements in the attempt to address those issues.RL3-TECT-NORTE-01-0124-FEDER-000020, cofinanced by North Portugal Regional Operational Program (ON.2-O Novo Norte), under the National Strategic Reference Framework, through the European Regional Development Fun

Hypertension and renin-angiotensin system blockers are not associated with expression of angiotensin-converting enzyme 2 (ACE2) in the kidney

AIMS: Angiotensin-converting enzyme 2 (ACE2) is the cellular entry point for severe acute respiratory syndrome coronavirus (SARS-CoV-2)-the cause of coronavirus disease 2019 (COVID-19). However, the effect of renin-angiotensin system (RAS)-inhibition on ACE2 expression in human tissues of key relevance to blood pressure regulation and COVID-19 infection has not previously been reported. METHODS AND RESULTS: We examined how hypertension, its major metabolic co-phenotypes, and antihypertensive medications relate to ACE2 renal expression using information from up to 436 patients whose kidney transcriptomes were characterized by RNA-sequencing. We further validated some of the key observations in other human tissues and/or a controlled experimental model. Our data reveal increasing expression of ACE2 with age in both human lungs and the kidney. We show no association between renal expression of ACE2 and either hypertension or common types of RAS inhibiting drugs. We demonstrate that renal abundance of ACE2 is positively associated with a biochemical index of kidney function and show a strong enrichment for genes responsible for kidney health and disease in ACE2 co-expression analysis. CONCLUSION: Our results indicate that neither hypertension nor antihypertensive treatment is likely to alter the expression of the key entry receptor for SARS-CoV-2 in the human kidney. Our data further suggest that in the absence of SARS-CoV-2 infection, kidney ACE2 is most likely nephro-protective but the age-related increase in its expression within lungs and kidneys may be relevant to the risk of SARS-CoV-2 infection