Interactions between maternal subtotal nephrectomy and salt: effects on renal function and the composition of plasma in the late gestation sheep fetus

Effects of altered maternal salt intake between 122 and 127 days gestation (term is 150 days) were studied in eight fetuses carried by ewes which had renal insufficiency caused by subtotal nephrectomy (STNxF) and seven fetuses carried by intact ewes (IntF). Plasma sodium and osmolality were increased in ewes with subtotal nephrectomy on a high-salt intake (0.17 m NaCl in place of drinking water for 5 days; P < 0.05). The STNxF had normal body weights. A high maternal salt intake did not affect fetal blood pressure or heart rate. Plasma osmolality was higher in STNxF (P < 0.001), and plasma sodium and osmolality were increased by high salt (P < 0.001 and P < 0.04, respectively). The STNxF had higher urinary osmolalities (P = 0.002), which were also increased by a high maternal salt intake (P = 0.03). Renal blood flow fell in STNxF in response to a high maternal salt intake, but increased in IntF (P = 0.003). In STNxF but not IntF, glomerular filtration rate and urinary protein excretion were positively related to fetal plasma renin levels (P < or = 0.01). It is concluded that the salt intake of pregnant ewes with renal insufficiency affects maternal and fetal osmolar balance, fetal plasma sodium and fetal renal function. Since STNxF also had altered renal haemodynamic responses to high maternal salt and evidence of renin-dependent glomerular filtration and protein excretion, we suggest that interactions between dietary salt and pre-existing maternal renal disease impair glomerular integrity and function in the fetus.     

Clinical research nursing: a critical resource in the national research enterprise

Translational clinical research has emerged as an important priority for the national research enterprise, with a clearly stated mandate to more quickly deliver prevention strategies, treatments and cures based on scientific innovations to the public. Within this national effort, a lack of consensus persists concerning the need for clinical nurses with expertise and specialized training in study implementation and the delivery of care to research participants. This paper reviews efforts to define and document the role of practicing nurses in implementing studies and coordinating clinical research in a variety of clinical settings, and differentiates this clinical role from the role of nurses as scientists and principal investigators. We propose an agenda for building evidence that having nurses provide and coordinate study treatments and procedures can potentially improve research efficiency, participant safety, and the quality of research data. We also provide recommendations for the development of the emerging specialty of clinical research nursing.     

The hazards of caring

Nurses may be at increased risk of non-communicable diseases such as cancer and asthma because of their exposure to hazardous substances in the workplace. Environmental and health groups are working together to persuade hospitals to adopt green practices that are better for the planet and safer for healthcare staff.     

Physical activity and mental well-being in student nurses

There is strong evidence that suggests physical activity can enhance mental well-being. However, this relationship has not been widely investigated in student nurses. A cross-sectional study was conducted to examine the relationship between physical activity and mental well-being in undergraduate student nurses (n=215). Physical activity was measured using the International Physical Activity Questionnaire. Other outcomes included self-esteem, anxiety, depression, life satisfaction, outcome expectations and self-efficacy. Almost, a quarter (23.8%) of the total sample, were meeting the Department of Health's physical activity guideline. Mean body mass index (BMI) was 25.0 with 40% being in the overweight to morbidly obese category. Self-esteem was significantly positively correlated with total physical activity (r=0.16, p=0.038) and moderate intensity activity (r=0.17, p=0.021). No other significant relationships were found between anxiety, depression and satisfaction with life and physical activity. Outcome expectations for exercise and self-efficacy were significantly positively correlated with moderate (r=0.17, p=0.019) and vigorous (r=0.28, p=0.000) intensity activity and total physical activity (r=0.29, p=0.000). BMI was significantly positively correlated with age (r=0.242, p=0.001), significantly negatively correlated with self-efficacy for exercise (r=0.257, p=0.000) and satisfaction with life (r=-0.144, p=0.041). Regression analysis showed that low self efficacy for exercise and increasing age were significant predictors of BMI with a small effect size r(2)=0.126, adjusted r(2)=0.112. BMI and physical activity variables collectively explained only 2% of the variance for anxiety, 4% for depression, 5% for self esteem and 6% for satisfaction with life. BMI was a significant predictor of satisfaction with life (Beta=-0.171, p=0.027). Participation in physical activity may be influential in improving mental well-being in student nurses. Promoting physical activity in student nurses has the potential to increase self-esteem and life satisfaction and decrease the risk of anxiety and depression. Further research is needed to establish whether this relationship is causal and exists in other student nurse populations.     

Rapid kinetics to peak serum antibodies is achieved following influenza vaccination by dry-coated densely packed microprojections to skin

A rapid time to peak serum antibody response following vaccination is particularly important for influenza: the time window between the availability of appropriate antigen and the start of the seasonal epidemic is very short. In this paper, influenza vaccine was delivered to both the epidermis and dermis of mouse skin using densely packed microprojection arrays for vaccination. We found that, after vaccination, around 75% and 90% of the delivered influenza vaccine migrated away from the ear skin within just 2 days and 1 week - respectively. And the time to peak serum antibody response was as early as 2 weeks. This result matches the kinetics achieved by intramuscular injection of liquid vaccine to muscle. Thus, we demonstrate that skin delivery of small vaccine volumes discretely by thousands of densely packed microprojections neither induces delay in kinetics nor interferes with the long-lasting antibody response; compared to conventional intramuscular injection.     

Changes in primary lymphoid organs with aging

Aging is associated with decreased immune function that leads to increased morbidity and mortality in the elderly. Immune senescence is accompanied by age-related changes in two primary lymphoid organs, bone marrow and thymus, that result in decreased production and function of B and T lymphocytes. In bone marrow, hematopoietic stem cells exhibit reduced self-renewal potential, increased skewing toward myelopoiesis, and decreased production of lymphocytes with aging. These functional sequelae of aging are caused in part by increased oxidative stress, inflammation, adipocyte differentiation, and disruption of hypoxic osteoblastic niches. In thymus, aging is associated with tissue involution, exhibited by a disorganization of the thymic epithelial cell architecture and increased adiposity. This dysregulation correlates with a loss of stroma-thymocyte ‘cross-talk’, resulting in decreased export of naïve T cells. Mounting evidence argues that with aging, thymic inflammation, systemic stress, local Foxn1 and keratinocyte growth factor expression, and sex steroid levels play critical roles in actively driving thymic involution and overall adaptive immune senescence across the lifespan. With a better understanding of the complex mechanisms and pathways that mediate bone marrow and thymus involution with aging, potential increases for the development of safe and effective interventions to prevent or restore loss of immune function with aging.