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Progress in Neuro-psychopharmacology &... Jun 2020The neuroendocrine system (NES) plays a crucial role in synchronizing the physiology and behavior of the whole organism in response to environmental constraints. The NES... (Review)
Review
The neuroendocrine system (NES) plays a crucial role in synchronizing the physiology and behavior of the whole organism in response to environmental constraints. The NES consists of a hypothalamic-pituitary-target organ axis that acts in coordination to regulate growth, reproduction, stress and basal metabolism. The growth (or somatotropic), hypothalamic-pituitary-gonadal (HPG), hypothalamic-pituitary-adrenal (HPA) and hypothalamic-pituitary-thyroid (HPT) axes are therefore finely tuned by the hypothalamus through the successive release of hypothalamic and pituitary hormones to control the downstream physiological functions. These functions rely on a complex set of mechanisms requiring tight synchronization between peripheral organs and the hypothalamic-pituitary complex, whose functionality can be altered during aging. Here, we review the results of research on the effects of aging on the NES of nonhuman primate (NHP) species in wild and captive conditions. A focus on the age-related dysregulation of the master circadian pacemaker, which, in turn, alters the synchronization of the NES with the organism environment, is proposed. Finally, practical and ethical considerations of using NHP models to test the effects of nutrition-based or hormonal treatments to combat the deterioration of the NES are discussed.
Topics: Aging; Animals; Humans; Hypothalamo-Hypophyseal System; Neurosecretory Systems; Pituitary Hormones; Pituitary-Adrenal System; Primates; Reproduction; Species Specificity
PubMed: 31891735
DOI: 10.1016/j.pnpbp.2019.109854 -
Minerva Anestesiologica 1999Sepsis is a condition at high risk for the patients to develop organ(s) or system dysfunction/failure and represent a very limiting process for survival. Researchers and... (Review)
Review
Sepsis is a condition at high risk for the patients to develop organ(s) or system dysfunction/failure and represent a very limiting process for survival. Researchers and clinicians proposed standardization of terminology for sepsis and related problems to improve communication and to evaluate the efficacy of preventive measures and therapeutic interventions. Interrelationship among systemic inflammatory response syndrome (SIRS), infection and sepsis are surrounded by non infectious satellite events such as trauma, burns, pancreatitis, haemorrhagic shock, immune-mediated organ injury and infectious cause such as fungemia, parasitemia, viremia. The prevalence of infections among intensive care patients has been reported to vary from 15 to 40%. Usually indicators of sepsis are persistent hyperlactatemia and supranormal level of DO2. These conditions may progress as a sort of dynamic process known as endotoxaemia condition which is mediated by derangement of biohumoral factors inducing immunological dissonance and ultimately concomitant or sequential organs dysfunction/failure. Multiple sources of sepsis is a phenomenon clearly associated with poor prognosis and all the sepsis trials managed in the last decades have failed on reducing mortality rate in enrolled patients. Development of scoring system routinely used at bedside represent an important method to establish cost-effectiveness in this exiting area of study and clinical management. Controversial results on sepsis need a sort of consensus at different level from researchers to clinician experiencing new strategies for prevention and more appropriately therapeutic approach for the management of this syndrome.
Topics: Humans; Multiple Organ Failure; Sepsis
PubMed: 10479840
DOI: No ID Found -
Digestion 2004The prognosis for critically ill cirrhotic patients depends on the extent of hepatic and extrahepatic organ dysfunction/failure. We hypothesize that a graded multiple... (Clinical Trial)
Clinical Trial Comparative Study
OBJECTIVES
The prognosis for critically ill cirrhotic patients depends on the extent of hepatic and extrahepatic organ dysfunction/failure. We hypothesize that a graded multiple organ dysfunction score, sequential organ failure assessment (SOFA), would provide more descriptive and discriminative power for predicting the hospital mortality for critically ill cirrhotic patients than the classical organ system failure (OSF) score, which defines organ failure as an all-or-none phenomenon.
METHODS
160 patients diagnosed with liver cirrhosis were admitted to the medical intensive care unit (ICU) from January 2002 to June 2003. Information considered necessary for calculating the Child-Pugh, OSF and SOFA scores on ICU admission was collected prospectively.
RESULTS
Hepatitis B infection was the most common cause of liver cirrhosis. A significantly progressive increase in mortality rate was associated with OSF and SOFA scores (p < 0.001). Close correlation between OSF and SOFA scores (p < 0.001) suggested that both systems evaluated the same event. In patients with similar organ dysfunction, the number of failed organ system(s) was significantly higher among non-survivors. However, no correlation existed between the SOFA scores and mortality rate in patients with the same OSF number. Meanwhile, both OSF and SOFA scores displayed excellent discriminative power (areas under receiver-operating characteristic (AUROC) were 0.906 and 0.892, respectively), while Child-Pugh scores clearly performed more poorly (AUROC 0.712). Both OSF and SOFA demonstrate a good fit using the Hosmer and Lemeshow goodness-of-fit test.
CONCLUSIONS
Both OSF and SOFA scores are excellent tools for predicting prognosis for cirrhotic patients admitted to ICU. Both of them are superior to Child-Pugh score. Hospital mortality for critically ill cirrhotic patients occurs owing to severe failure of a relatively few organs, rather than because of an accumulation of mild dysfunction in many organ systems. Graded organ dysfunction scales provide no further benefit for predicting hospital mortality for critically ill cirrhotic patients.
Topics: Adult; Aged; Female; Hepatitis B; Humans; Liver Cirrhosis; Male; Middle Aged; Multiple Organ Failure; Prognosis; Sensitivity and Specificity; Severity of Illness Index; Survival Analysis
PubMed: 15178929
DOI: 10.1159/000078789 -
Current Opinion in Plant Biology Feb 2003Control of the shape and size of indeterminate organs, such as roots and stems, is directly related to the control of the shape and size of the cells in these organs, as... (Review)
Review
Control of the shape and size of indeterminate organs, such as roots and stems, is directly related to the control of the shape and size of the cells in these organs, as predicted by orthodox cell theory. For example, the polarity-dependent growth of leaf cells directly affects the polar expansion of leaves. Thus, the control of leaf shape is related to the control of the shape of cells within the leaf, as suggested by cell theory. By contrast, in determinate organs, such as leaves, the number of cells does not necessarily reflect organ shape or size. Genetic evidence shows that a compensatory system(s) is involved in leaf morphogenesis, and that an increase in cell volume can be triggered by a decrease in cell number and vice versa. Studies of chimeric leaves also suggest interaction between leaf cells that coordinates the behaviour of these cells at the organ level. Moreover, leaf size also appears to be coordinated at the whole-plant level. The recently hypothesised neo cell theory describes how leaf shape- and size-control mechanisms control leaf shape at the organ-level via cell-cell interaction.
Topics: Arabidopsis; Cell Count; Cell Division; Cell Size; Morphogenesis; Plant Leaves; Signal Transduction
PubMed: 12495752
DOI: 10.1016/s1369526602000055 -
Frontiers in Neuroscience 2021In the natural environment, organisms are constantly exposed to a continuous stream of sensory input. The dynamics of sensory input changes with organism's behaviour and... (Review)
Review
In the natural environment, organisms are constantly exposed to a continuous stream of sensory input. The dynamics of sensory input changes with organism's behaviour and environmental context. The contextual variations may induce >100-fold change in the parameters of the stimulation that an animal experiences. Thus, it is vital for the organism to adapt to the new diet of stimulation. The response properties of neurons, in turn, dynamically adjust to the prevailing properties of sensory stimulation, a process known as "neuronal adaptation." Neuronal adaptation is a ubiquitous phenomenon across all sensory modalities and occurs at different stages of processing from periphery to cortex. In spite of the wealth of research on contextual modulation and neuronal adaptation in visual and auditory systems, the neuronal and computational basis of sensory adaptation in somatosensory system is less understood. Here, we summarise the recent finding and views about the neuronal adaptation in the rodent whisker-mediated tactile system and further summarise the functional effect of neuronal adaptation on the response dynamics and encoding efficiency of neurons at single cell and population levels along the whisker-mediated touch system in rodents. Based on direct and indirect pieces of evidence presented here, we suggest sensory adaptation provides context-dependent functional mechanisms for noise reduction in sensory processing, salience processing and deviant stimulus detection, shift between integration and coincidence detection, band-pass frequency filtering, adjusting neuronal receptive fields, enhancing neural coding and improving discriminability around adapting stimuli, energy conservation, and disambiguating encoding of principal features of tactile stimuli.
PubMed: 34776857
DOI: 10.3389/fnins.2021.770011 -
International Journal of Molecular... May 2016Circadian rhythms, ≈24 h oscillations in behavior and physiology, are reflected in all cells of the body and function to optimize cellular functions and meet... (Review)
Review
Circadian rhythms, ≈24 h oscillations in behavior and physiology, are reflected in all cells of the body and function to optimize cellular functions and meet environmental challenges associated with the solar day. This multi-oscillatory network is entrained by the master pacemaker located in the suprachiasmatic nucleus (SCN) of the hypothalamus, which directs an organism's rhythmic expression of physiological functions and behavior via a hierarchical system. This system has been highly conserved throughout evolution and uses transcriptional-translational autoregulatory loops. This master clock, following environmental cues, regulates an organism's sleep pattern, body temperature, cardiac activity and blood pressure, hormone secretion, oxygen consumption and metabolic rate. Mammalian peripheral clocks and clock gene expression have recently been discovered and are present in all nucleated cells in our body. Like other essential organ of the body, the skin also has cycles that are informed by this master regulator. In addition, skin cells have peripheral clocks that can function autonomously. First described in 2000 for skin, this review summarizes some important aspects of a rapidly growing body of research in circadian and ultradian (an oscillation that repeats multiple times during a 24 h period) cutaneous rhythms, including clock mechanisms, functional manifestations, and stimuli that entrain or disrupt normal cycling. Some specific relationships between disrupted clock signaling and consequences to skin health are discussed in more depth in the other invited articles in this IJMS issue on Sleep, Circadian Rhythm and Skin.
Topics: Animals; Circadian Clocks; Circadian Rhythm; Gene Expression; Gene Expression Regulation; Humans; Skin Physiological Phenomena; Suprachiasmatic Nucleus
PubMed: 27231897
DOI: 10.3390/ijms17060801 -
Aging Dec 2021The circadian clock system influences the biology of life by establishing circadian rhythms in organisms, tissues, and cells, thus regulating essential biological...
The circadian clock system influences the biology of life by establishing circadian rhythms in organisms, tissues, and cells, thus regulating essential biological processes based on the day/night cycle. Circadian rhythms change over a lifetime due to maturation and aging, and disturbances in the control of the circadian system are associated with several age-related pathologies. However, the impact of chronobiology and the circadian system on healthy organ and tissue aging remains largely unknown. Whether aging-related changes of the circadian system's regulation follow a conserved pattern across different species and tissues, hence representing a common driving force of aging, is unclear. Based on a cross-sectional transcriptome analysis covering 329 RNA-Seq libraries, we provide indications that the circadian system is subjected to aging-related gene alterations shared between evolutionarily distinct species, such as , , , and . We discovered differentially expressed genes by comparing tissue-specific transcriptional profiles of mature, aged, and old-age individuals and report on six genes (, , , , , and ) of the circadian system, which show conserved aging-related expression patterns in four organs of the species examined. Our results illustrate how the circadian system and aging might influence each other in various tissues over a long lifespan and conceptually complement previous studies tracking short-term diurnal and nocturnal gene expression oscillations.
Topics: Aged; Aging; Animals; Circadian Clocks; Circadian Rhythm; Cross-Sectional Studies; Humans; Longevity; Mice; Transcriptome; Zebrafish
PubMed: 34923482
DOI: 10.18632/aging.203788 -
Current Opinion in Organ Transplantation Jun 2023Renal transplantation systems across the world aim to achieve an optimal balance between fair access to deceased donor kidney transplants (equity) and efficient use of... (Review)
Review
PURPOSE OF REVIEW
Renal transplantation systems across the world aim to achieve an optimal balance between fair access to deceased donor kidney transplants (equity) and efficient use of organs (utility). Kidney allocation systems are measured across a host of metrics, and there is no single agreed upon definition of success, which looks different for each system depending on the desired balance between equity and utility. This article evaluates the United States renal transplantation system's efforts to balance equity and utility while drawing comparisons to other national systems.
RECENT FINDINGS
The United States renal transplantation system is expected to undergo major changes with the transition to a continuous distribution framework. The continuous distribution framework removes geographic boundaries and takes a flexible and transparent approach to balancing equity and utility. The framework leverages transplant professionals and community members input with mathematical optimization strategies to inform weighting of patient factors to allocate deceased donor kidneys.
SUMMARY
The United States' proposed continuous allocation framework lays the groundwork for a system allowing transparent balancing of equity and utility. This system approach addresses issues common to those in many other countries.
Topics: Humans; United States; Kidney Transplantation; Tissue and Organ Procurement; Tissue Donors; Transplants; Repressor Proteins; Waiting Lists
PubMed: 36995686
DOI: 10.1097/MOT.0000000000001059 -
Integrative and Comparative Biology Dec 2023Motility is an essential factor for an organism's survival and diversification. With the advent of novel single-cell technologies, analytical frameworks, and theoretical... (Review)
Review
Motility is an essential factor for an organism's survival and diversification. With the advent of novel single-cell technologies, analytical frameworks, and theoretical methods, we can begin to probe the complex lives of microscopic motile organisms and answer the intertwining biological and physical questions of how these diverse lifeforms navigate their surroundings. Herein, we summarize the main mechanisms of microscale motility and give an overview of different experimental, analytical, and mathematical methods used to study them across different scales encompassing the molecular-, individual-, to population-level. We identify transferable techniques, pressing challenges, and future directions in the field. This review can serve as a starting point for researchers who are interested in exploring and quantifying the movements of organisms in the microscale world.
Topics: Animals; Movement; Single-Cell Analysis; Models, Theoretical; Cell Movement; Bacteria
PubMed: 37336589
DOI: 10.1093/icb/icad075 -
Annual Review of Physiology 2015Acid-base homeostasis is essential for life. The macromolecules upon which living organisms depend are sensitive to pH changes, and physiological systems use the... (Review)
Review
Acid-base homeostasis is essential for life. The macromolecules upon which living organisms depend are sensitive to pH changes, and physiological systems use the equilibrium between carbon dioxide, bicarbonate, and protons to buffer their pH. Biological processes and environmental insults are constantly challenging an organism's pH; therefore, to maintain a consistent and proper pH, organisms need sensors that measure pH and that elicit appropriate responses. Mammals use multiple sensors for measuring both intracellular and extracellular pH, and although some mammalian pH sensors directly measure protons, it has recently become apparent that many pH-sensing systems measure pH via bicarbonate-sensing soluble adenylyl cyclase.
Topics: Acid Sensing Ion Channels; Acid-Base Equilibrium; Acid-Base Imbalance; Adenylyl Cyclases; Animals; Bicarbonates; Carbon Dioxide; Homeostasis; Humans; Hydrogen-Ion Concentration; Protons
PubMed: 25340964
DOI: 10.1146/annurev-physiol-021014-071821