Estimating nephron number in the developing kidney using the physical disector/fractionator combination

Over the last decade the development of new molecular biology tools, advanced microscopy, live imaging and systems biology approaches have revolutionized our conception of how embryonic development proceeds. One fundamental aspect of development biology is the concept of morphogenesis: understanding how a group of multipotent cells organize and differentiate into a complex organ. In Kidney Development: Methods and Protocols, expert researchers in the field detail different approaches to tackle kidney development. These approaches include culture and live imaging aspects of kidney development, analyzing the 3-dimensional aspects of branching morphogenesis as well as nephrogenesis, manipulation of the gene/protein expression during kidney development as well as in the adult kidney, and how to assess kidney malformation and disease. Written in the highly successful Methods in Molecular Biology series format, chapters include introductions to their respective topics, lists of the necessary materials and reagents, step-by-step, readily reproducible laboratory protocols, and key tips on troubleshooting and avoiding known pitfalls. Authoritative and practical, Kidney Development: Methods and Protocols seeks to aid scientists in the further study of the process of morphogenesis which is fundamental important not only for studying developmental biology but also for regenerative medicine.

Creatine pretreatment prevents birth asphyxia–induced injury of the newborn spiny mouse kidney

Background:
Acute kidney injury (AKI) is a major complication for infants following an asphyxic insult at birth. We aimed to determine if kidney structure and function were affected in an animal model of birth asphyxia and if maternal dietary creatine supplementation could provide an energy reserve to the fetal kidney, maintaining cellular respiration during asphyxia and preventing AKI.

Methods:
Pregnant spiny mice were maintained on normal chow or chow supplemented with creatine from day 20 gestation. On day 38 (term ~39 d), pups were delivered by cesarean section (c-section) or subjected to intrauterine asphyxia. Twenty-four hours after insult, kidneys were collected for histological or molecular analysis. Urine and plasma were also collected for biochemical analysis.

Results:
AKI was evident at 24 h after birth asphyxia, with a higher incidence of shrunken glomeruli (P < 0.02), disturbance to tubular arrangement, tubular dilatation, a twofold increase (P < 0.02) in expression of Ngal (early marker of kidney injury), and decreased expression of the podocyte differentiation marker nephrin. Maternal creatine supplementation prevented the glomerular and tubular abnormalities observed in the kidney at 24 h and the increased expression of Ngal.

Conclusion:
Maternal creatine supplementation may prove useful in ameliorating kidney injury associated with birth asphyxia.

Mothers requiring dialysis: parenting and end-stage kidney disease

Background
Mothers requiring dialysis to treat end-stage kidney disease face the challenging demands of the disease and dialysis treatment in addition to their role as a parent.

Objective
To describe the experience of mothers who require haemodialysis.

Methods
Four mothers receiving haemodialysis treatment for end-stage kidney disease in regional Australia were interviewed to explore the mothers' experiences, attitudes, beliefs and values of their dual role as mothers and haemodialysis recipients.

Results
The overarching theme emerging from the data was the competing roles of motherhood and dialysis. Four key sub-themes emerged: fitting everything in, internal family challenges, lost connections and striving for normality.

Conclusion
Being a mother adds a range of complexities to being on dialysis. While managing dialysis, mothers struggle to care for their children and stay connected with family life. Nephrology health professionals are uniquely placed to support mothers and need to develop strategies to ease their burdens of care.

Altered responsiveness of the kidney to activation of the renal nerves in fat-fed rabbits

We tested whether mild adiposity alters responsiveness of the kidney to activation of the renal sympathetic nerves. After rabbits were fed a high-fat or control diet for 9 wk, responses to reflex activation of renal sympathetic nerve activity (RSNA) with hypoxia and electrical stimulation of the renal nerves (RNS) were examined under pentobarbital anesthesia. Fat pad mass and body weight were, respectively, 74% and 6% greater in fat-fed rabbits than controls. RNS produced frequency-dependent reductions in renal blood flow, cortical and medullary perfusion, glomerular filtration rate, urine flow, and sodium excretion and increased renal plasma renin activity (PRA) overflow. Responses of sodium excretion and medullary perfusion were significantly enhanced by fat feeding. For example, 1 Hz RNS reduced sodium excretion by 79 ± 4% in fat-fed rabbits and 46 ± 13% in controls. RNS (2 Hz) reduced medullary perfusion by 38 ± 11% in fat-fed rabbits and 9 ± 4% in controls. Hypoxia doubled RSNA, increased renal PRA overflow and medullary perfusion, and reduced urine flow and sodium excretion, without significantly altering mean arterial pressure (MAP) or cortical perfusion. These effects were indistinguishable in fat-fed and control rabbits. Neither MAP nor PRA were significantly greater in conscious fat-fed than control rabbits. These observations suggest that mild excess adiposity can augment the antinatriuretic response to renal nerve activation by RNS, possibly through altered neural control of medullary perfusion. Thus, sodium retention in obesity might be driven not only by increased RSNA, but also by increased responsiveness of the kidney to RSNA.

A design-based method for estimating glomerular number in the developing kidney

Low glomerular (nephron) endowment has been associated with an increased risk of cardiovascular and renal disease in adulthood. Nephron endowment in humans is determined by 36 wk of gestation, while in rats and mice nephrogenesis ends several days after birth. Specific genes and environmental perturbations have been shown to regulate nephron endowment. Until now, design-based method for estimating nephron number in developing kidneys was unavailable. This was due in part to the difficulty associated with unambiguously identifying developing glomeruli in histological sections. Here, we describe a method that uses lectin histochemistry to identify developing glomeruli and the physical disector/fractionator principle to provide unbiased estimates of total glomerular number (Nglom). We have characterized Nglom throughout development in kidneys from 76 rats and model this development with a 5-parameter logistic equation to predict Nglom from embryonic day 17.25 to adulthood (r2 = 0.98). This approach represents the first design-based method with which to estimate Nglom in the developing kidney.

Self-management programmes in stages 1–4 chronic kidney disease: a literature review

Background
Chronic kidney disease (CKD) is a complex health problem, which requires individuals to invest considerable time and energy in managing their health and adhering to multifaceted treatment regimens.

Objectives
To review studies delivering self-management interventions to people with CKD (Stages 1–4) and assess whether these interventions improve patient outcomes.

Design
Systematic review.

Methods
Nine electronic databases (MedLine, CINAHL, EMBASE, ProQuest Health & Medical Complete, ProQuest Nursing & Allied Health, The Cochrane Library, The Joanna Briggs Institute EBP Database, Web of Science and PsycINFO) were searched using relevant terms for papers published between January 2003 and February 2013.

Results
The search strategy identified 2,051 papers, of which 34 were retrieved in full with only 5 studies involving 274 patients meeting the inclusion criteria. Three studies were randomised controlled trials, a variety of methods were used to measure outcomes, and four studies included a nurse on the self-management intervention team. There was little consistency in the delivery, intensity, duration and format of the self-management programmes. There is some evidence that knowledge- and health-related quality of life improved. Generally, small effects were observed for levels of adherence and progression of CKD according to physiologic measures.

Conclusion
The effectiveness of self-management programmes in CKD (Stages 1–4) cannot be conclusively ascertained, and further research is required. It is desirable that individuals with CKD are supported to effectively self-manage day-to-day aspects of their health.

Interventions to improve medication adherence in adult kidney transplant recipients: a systematic review.

In kidney transplantation, adherence to immunosuppressive therapy is paramount for long-term graft survival. This systematic review aimed to assess the effectiveness of interventions to improve medication adherence in adult kidney transplantation.

Medicine non-adherence in kidney transplantation

Background: The increasing prevalence of chronic kidney disease, the relative shortage of kidney donors and the economic- and health-related costs of kidney transplant rejection make the prevention of adverse outcomes following transplantation a healthcare imperative. Although strict adherence to immunosuppressant medicine regimens is key to preventing kidney rejection, evidence suggests that adherence is sub-optimal. Strategies need to be developed to help recipients of kidney transplants adhere to their prescribed medicines. Findings: This review has found that a number of factors contribute to poor adherence, for example, attitudes towards medicine taking and forgetfulness. Few investigations have been conducted, however, on strategies to enhance medicine adherence in kidney transplant recipients. Strategies that may improve adherence include pharmacist-led interventions (incorporating counselling, medicine reviews and nephrologist liaison) and nurse-led interventions (involving collaboratively working with recipients to understand their routines and offering solutions to improve adherence). Strategies that have shown to have limited effectiveness include supplying medicines free of charge and providing feedback on a participant's medicine adherence without any educational or behavioural interventions. Conclusion: Transplantation is the preferred treatment option for people with end-stage kidney disease. Medicine non-adherence in kidney transplantation increases the risk of rejection, kidney loss and costly treatments. Interventions are needed to help the transplant recipient take all their medicines as prescribed to improve general well-being, medicine safety and reduce healthcare costs. © 2014 European Dialysis and Transplant Nurses Association/European Renal Care Association.