Renal Prostaglandins in Human Adaptation to Modifications of Sodium Balance

ABSTRACT Variations in plasma renin activity and urinary aldosterone excretion were studied in normal subjects submitted to salt restriction and simultaneous inhibition of ACTH production with a new synthetic steroid, 6-dehydro-16-methylene hydrocortisone (STC 407). At a dose of 10 mg t. i. d. this preparation exerts an inhibitory effect on the pituitary comparable to that of 2 mg of dexamethasone. In subjects maintained on a restricted salt intake, STC 407 does not delay the establishment of an equilibrium in sodium balance. The increases in endogenous aldosterone production and in plasma renin activity are also similar to those seen in the control subjects. A possible mineralocorticoid effect of STC 407 can be excluded. Under identical experimental conditions, the administration of dexamethasone yielded results comparable to those obtained with STC 407.

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Narrative as active inference

10.31234/osf.io/47ub6 ◽

2020 ◽

Cited By ~ 1

Author(s):

Nabil Bouizegarene ◽

maxwell ramstead ◽

Axel Constant ◽

Karl Friston ◽

Laurence Kirmayer

Keyword(s):

Well Being ◽

Social Practices ◽

Human Adaptation ◽

Active Inference ◽

Future Projection ◽

Future Developments ◽

The Social ◽

Parsimonious Model ◽

Living Organisms ◽

Theory Research

The ubiquity and importance of narratives in human adaptation has been recognized by many scholars. Research has identified several functions of narratives that are conducive to individuals’ well-being and adaptation as well as to coordinated social practices and enculturation. In this paper, we characterize the social and cognitive functions of narratives in terms of the framework of active inference. Active inference depicts the fundamental tendency of living organisms to adapt by creating, updating, and maintaining inferences about their environment. We review the literature on the functions of narratives in identity, event segmentation, episodic memory, future projection, storytelling practices, and enculturation. We then re-cast these functions of narratives in terms of active inference, outlining a parsimonious model that can guide future developments in narrative theory, research, and clinical applications.

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Faculty Opinions recommendation of Human adaptation to arsenic-rich environments.

Faculty Opinions – Post-Publication Peer Review of the Biomedical Literature ◽

10.3410/f.726095579.793513775 ◽

2016 ◽

Author(s):

Sarah Tishkoff ◽

Meagan Rubel

Keyword(s):

Human Adaptation

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Neuronal nitric oxide synthase and systemic vasodilation in rats with cirrhosis

AJP Renal Physiology ◽

10.1152/ajprenal.2000.279.6.f1110 ◽

2000 ◽

Vol 279 (6) ◽

pp. F1110-F1115 ◽

Cited By ~ 50

Author(s):

Lieming Xu ◽

Ethan P. Carter ◽

Mamiko Ohara ◽

Pierre-Yves Martin ◽

Boris Rogachev ◽

...

Keyword(s):

Nitric Oxide ◽

Liver Cirrhosis ◽

Nitric Oxide Synthase ◽

Control Treatment ◽

Sodium Balance ◽

Hyperdynamic Circulation ◽

Molecular Approaches ◽

Advanced Liver Cirrhosis ◽

Oxide Synthase

Cirrhosis is typically associated with a hyperdynamic circulation consisting of low blood pressure, low systemic vascular resistance (SVR), and high cardiac output. We have recently reported that nonspecific inhibition of nitric oxide synthase (NOS) with nitro-l-arginine methyl ester reverses the hyperdynamic circulation in rats with advanced liver cirrhosis induced by carbon tetrachloride (CCl4). Although an important role for endothelial NOS (eNOS) is documented in cirrhosis, the role of neuronal NOS (nNOS) has not been investigated. The present study was carried out to specifically investigate the role of nNOS during liver cirrhosis. Specifically, physiological, biochemical, and molecular approaches were employed to evaluate the contribution of nNOS to the cirrhosis-related hyperdynamic circulation in CCl4-induced cirrhotic rats with ascites. Cirrhotic animals had a significant increase in water and sodium retention. In the aorta from cirrhotic animals, both nNOS protein expression and cGMP concentration were significantly elevated compared with control. Treatment of cirrhotic rats for 7 days with the specific nNOS inhibitor 7-nitroindazole (7-NI) normalized the low SVR and mean arterial pressure, elevated cardiac index, and reversed the positive sodium balance. Increased plasma arginine vasopressin concentrations in the cirrhotic animals were also repressed with 7-NI in association with diminished water retention. The circulatory changes were associated with a reduction in aortic nNOS expression and cGMP. However, 7-NI treatment did not restore renal function in cirrhotic rats (creatinine clearance: 0.76 ± 0.03 ml · min−1· 100 g body wt−1in cirrhotic rats vs. 0.79 ± 0.05 ml · min−1· 100 g body wt−1in cirrhotic rats+7-NI; P NS.). Taken together, these results indicate that nNOS-derived NO contributes to the development of the hyperdynamic circulation and fluid retention in cirrhosis.

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Global evidence of constraints and limits to human adaptation

Regional Environmental Change ◽

10.1007/s10113-021-01808-9 ◽

2021 ◽

Vol 21 (3) ◽

Author(s):

Adelle Thomas ◽

Emily Theokritoff ◽

Alexandra Lesnikowski ◽

Diana Reckien ◽

Kripa Jagannathan ◽

...

Keyword(s):

Climate Change ◽

Systematic Review ◽

Behavioral Adaptation ◽

Human Adaptation ◽

Small Islands ◽

Intergovernmental Panel ◽

Natural Systems ◽

Adaptation Response ◽

Cultural Constraints ◽

Global Evidence

AbstractConstraints and limits to adaptation are critical to understanding the extent to which human and natural systems can successfully adapt to climate change. We conduct a systematic review of 1,682 academic studies on human adaptation responses to identify patterns in constraints and limits to adaptation for different regions, sectors, hazards, adaptation response types, and actors. Using definitions of constraints and limits provided by the Intergovernmental Panel on Climate Change (IPCC), we find that most literature identifies constraints to adaptation but that there is limited literature focused on limits to adaptation. Central and South America and Small Islands generally report greater constraints and both hard and soft limits to adaptation. Technological, infrastructural, and ecosystem-based adaptation suggest more evidence of constraints and hard limits than other types of responses. Individuals and households face economic and socio-cultural constraints which also inhibit behavioral adaptation responses and may lead to limits. Finance, governance, institutional, and policy constraints are most prevalent globally. These findings provide early signposts for boundaries of human adaptation and are of high relevance for guiding proactive adaptation financing and governance from local to global scales.

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