Young Organism Research Articles

The amazing ubiquitin-proteasome system: structural components and implication in aging.

Proteome quality control (PQC) is critical for the maintenance of cellular functionality and it is assured by the curating activity of the proteostasis network (PN). PN is constituted of several complex protein machines that under conditions of proteome instability aim to, firstly identify, and then, either rescue or degrade nonnative polypeptides. Central to the PN functionality is the ubiquitin-proteasome system (UPS) which is composed from the ubiquitin-conjugating enzymes and the proteasome; the latter is a sophisticated multi-subunit molecular machine that functions in a bimodal way as it degrades both short-lived ubiquitinated normal proteins and nonfunctional polypeptides. UPS is also involved in PQC of the nucleus, the endoplasmic reticulum and the mitochondria and it also interacts with the other main cellular degradation axis, namely the autophagy-lysosome system. UPS functionality is optimum in the young organism but it is gradually compromised during aging resulting in increasing proteotoxic stress; these effects correlate not only with aging but also with most age-related diseases. Herein, we present a synopsis of the UPS components and of their functional alterations during cellular senescence or in vivo aging. We propose that mild UPS activation in the young organism will, likely, promote antiaging effects and/or suppress age-related diseases.

The roles of cellular and organismal aging in the development of late-onset maladies.

Numerous disorders, including neurodegenerative diseases and certain types of cancer, manifest late in life. This common feature raises the prospect that an aging-associated decline in the activity of cellular and organismal maintenance mechanisms enables the emergence of these maladies in late life stages. Accordingly, the alteration of aging bears the promise of harnessing the mechanisms that protect the young organism to prevent illness in the elderly. The identification of aging-regulatory pathways has enabled scrutiny of this hypothesis and revealed that the alteration of aging protects invertebrates and mammals from toxic protein aggregation linked to neurodegeneration and from cancer. Here we review the current knowledge on the regulation of aging at the cellular and organismal levels, delineate the mechanistic links between aging and late-onset disorders, describe efforts to develop compounds that protect from these maladies by selectively manipulating aging, and discuss future research directions and possible therapeutic implications of this approach.

Codzienny i cotygodniowy okres wypoczynku

In the article issues of the daily and weekly rest periods of rest were addressed in the light of provisions of the labour law. The legislator in the Labour Code has implemented regulations that guarantee periods of rest. The employee is entitled to the time of rest in order to be able to effectively perform one's duties. Therefore during every twenty-four hours the employee has the right to at least 11 consecutive hours of the rest. However the weekly rest periods should include at least 35 hours, including at least 11 consecutive hours of daily rest period. If daily dimension of employee’s work amounts to at least 6 hours, then he is entitled to 15 minutes of the break included in working hours. Work performed in the overtime, extends working hours of the worker and therefore the legislator clearly determined conditions which must be fulfilled to use this institution. Overtime work should be compensated to an employee through additional remuneration of compensatory rest period. Working hours of young workers comparing to working hours of adult workers were shortened and adapted for their age and the young organism that needs more rest. Also a time of the learning is included in working hours of young workers therefore effectively their working hours are shorter than of remaining employees.

The nematode Caenorhabditis elegans: A versatile model for the study of proteotoxicity and aging

Toxicity arising from protein misfolding and aggregation (proteotoxicity) is tightly mechanistically linked to the emergence of late-onset neurodegenerative disorders such as Alzheimer’s and Parkinson’s diseases. Why these maladies manifest in late stages of life and what mechanisms protect the young organism from disease are key enigmas. The nematode Caenorhabditis elegans offers key advantages that enable systematic exploration of many cell biological and functional aspects of neurodegeneration-linked proteotoxicity. Here we review the abundantly used nematode-based proteotoxicity models and delineate common techniques for the measurement of protein aggregation and rate of proteotoxicity. We also discuss the advantages offered by the worm for genetic screening, drug development and for the exploration of the links between proteotoxicity and the aging process.

Medial prefrontal cortex processes threatening stimuli in juvenile rats.

To survive, all mammalian species must recognize and respond appropriately to threatening stimuli. In adults, the prelimbic medial prefrontal cortex (mPFC) appears to be involved in fear expression, whereas the infralimbic mPFC mediates fear extinction. In juvenile rats (PN26), the mPFC receives information on potential predators but does not act on it. To test whether the prefrontal cortex is capable of fear regulation in the young organism, we exposed juvenile rats to a threatening or nonthreatening stimulus and assessed fear and brain Fos activation of the mPFC subdivisions, amygdala and periaqueductal gray (PAG). In response to the threat, juveniles froze more, spent more time far from the threat, and had elevated numbers of Fos-positive cells in the prelimbic mPFC, the medial amygdala, and ventral PAG. To test the hypothesis that the mPFC has a dual role in modulating the amygdala and PAG in juveniles, we pharmacologically disinhibited each of the two subdivisions of the mPFC and assessed freezing and downstream activation to the threat. Juvenile rats infused with picrotoxin into the prelimbic mPFC and exposed to a threatening stimulus froze less, spent less time far from the threat, and increased Fos expression. Infusion of picrotoxin into the infralimbic mPFC also reduced fear responding to the threatening stimulus but had no effect on Fos expression. In sum, it appears that the mPFC can process threatening stimuli in juveniles at this age, even though it is normally not involved in the fear responses.

Dependence of Cognitive Processes from the Individual Psychophysiological Characteristics of Upper-School Students of a Special Lyceum

The enrichment by highly information load of the school educational process, which leads in severe environment to psycho-emotional stress, confirms the necessity of studying the psycho-emotional and physiological stability of the senior schoolboys to information educational stress in rugged climate/geographic regions of Siberia. Observed were the 110 teenagers, the inhabitants of Novosibirsk, the students of 9th-10th classes of the special lycée. Clinical, psychological, psychophysiological, biochemical and hormonal methods of observation were used. It was shown that efficiency of the modern information-enriched educational process defines a complex of individual adaptive characteristics of an organism, including lateral phenotype of the prevalence of cerebral hemispheres, the stability of psychophysiological response, minimization of painful reaction to sharp changes of the factors of nature—meteosensitivity, and also the belonging to chronotypes (morning or evening). These features form the basis of stability of the young organism to the educational information stress and to the action of rugged climate-meteorological and biorhytmological factors, aggravating this stress.

Avoidance of influence of negative emotions on students' health

Aim of the article is to research the influence of negative emotions on students’ health, which may arise while testing academic achievements of future specialists and elaborate the directions of their avoidance. Material and methods. A range of theoretical and empirical methods is used. The questionnaire of 138 students is realised in Kharkiv National Agrarian University named after V.V. Dockuchayev. The results of the experiment are grounded by Macnamara’s method. Results. The reaction of a young organism to negative emotions during testing is revealed in a form of animosity, disorder of sleep, pain etc. It is determined that the least of harm is done during preliminary testing and much more – during current and concluding ones. Developed and approved directions of avoidance of such negatives are revealed. Conclusions. Testing by the studactive pedagogical technology created by us favours the avoidance of influence of negative emotions on students’ health.

The effect of comprehensive rehabilitation on correcting muscle imbalance in rural children from the Warmia and Mazury region

Abstract Introduction A complex problem concerning the disability of rural children stems from the specificity of a rural environment. Such an environment frequently serves as the source of negative stimuli, thus leading to muscle imbalances in children. Negative stimuli affecting personality, that children are exposed to sometimes for years, result in a local strain in a child's young organism, and then, commonly, in motor system dysfunctions. In this connection, muscle imbalance develops; whereas muscle balance conditions a correct body posture and appropriate functioning. Aim The aim of this study was to discover the sources of negative influences affecting a rural child's development and to design effective preventive measures. Consequently, the intended objective of the designed program was to provide professional rehabilitation for the largest number of children and youth having motor system dysfunctions as well as emotional disorders. Another goal of this program was to determine the effect of comprehensive rehabilitation on correcting muscle imbalance in rural children. Materials and methods This study comprised 50 children (30 girls and 20 boys) participating in a rehabilitation course designed for rural children as a three-week program. Children were examined by employing a specially devised chart of examinations and procedures in order to analyze and evaluate their functional problems in detail. Results and discussion A comprehensive rehabilitation program implemented by a team of therapists was in many cases beneficial with respect to rehabilitation outcomes: the restoration of muscle balance generated a decrease in or disappearance of the functional problem. Such improvement mostly involved children diagnosed with a shortened lower extremity, kyphosis (round back), winged scapula, or a low-grade functional scoliosis. Conclusions Examination results indicate that comprehensive therapy is required. Combining physical rehabilitation with psychotherapy eliminates the sources of negative stimuli that lead to the appearance of or to the increase in the motor system dysfunction. A child's conscious involvement in the therapeutic process and work performed in the framework of autotherapy are also very important.

Cutting the vagus nerve below the diaphragm prevents maternal potentiation of infant rat vocalization

In maternal potentiation, the rate of vocalization by a young organism during isolation is greatly enhanced if that isolation has been immediately preceded by an interaction with the mother (or other adult female in the case of rats). The enhancement in isolation-induced vocalization rate does not occur if the young animal had an interaction with other social companions like littermates or with familiar inanimate stimuli like home cage shavings. The present study demonstrates that pups whose vagus nerve is cut below the diaphragm do not potentiate vocalization after an interaction with their dam. The vocalization rates of denervated pups in a first isolation, in the presence of the dam, and during cold exposure do not differ from control pups. Their non-vocal behaviors also appear unaffected by the surgery. Similar to what has been shown in studies of fever-induced behavioral changes, an intact vagus nerve from the gut is necessary for young rat pups to show normal social mediation of their isolation-induced vocal responses.

Evaluation of the effectiveness of Chêneau brace treatment for idiopathic scoliosis – own observations

Abstract Introduction Progressive nature of scoliosis significantly affects the development and functioning of a young organism. The extensive interest of medical experts in spinal deformities stems from their high incidence in the population of youth (2–3%), health consequences resulting from the disease progression as well as high economic and social costs. Aim Evaluation of the effectiveness of the Cheneau brace in the treatment of idiopathic scoliosis. Materials and methods The research material comprised 302 patients treated in the Chair and Teaching Hospital of Rehabilitation and the Provincial Children's Hospital in Ameryka near Olsztyn, for idiopathic scoliosis, ranging in ages from 8 to 17. The observation period was from 2 to 5 years. Qualification for orthopedic brace was conducted according to the recommendations of an international group of experts. We analyzed radiograms in the antero-posterior projection taken during the treatment and assessed the Cobb angles. The treatment was finished after skeletal maturity was achieved. Results At the stage of research material analysis some patients were excluded for the following reasons: lack of skeletal maturity – 66 (21.8%), interrupted treatment – 110 (36.4%), co-existing diseases impacting on the clinical course of scoliosis – 47 (15.5%). The study group, i.e. 79 patients, who completed their treatment, were divided into sub-groups depending on the effect of their treatment. 20 patients improved (24.7%), 18 (22.2%) were stable, 9 (11.1%) worsened, and 32 (41.9%) were qualified for surgical procedure. Discussion Meta-analyses of international literature have shown that bracing is an effective therapeutic method for idiopathic scoliosis. However, our studies have shown that a large number of patients decide to finish their therapy too early or do not undertake brace treatment at all. Conclusions A large number of patients in the lowest mean age group (12.4 years) who were eventually qualified for surgical procedure is disconcerting. The best outcome of the Cheneau brace treatment was achieved in the group of the highest mean age of 14.3.

Aerobic abilities of young women organism as an indicator of their exercise performance

Aerobic abilities of young women organism as an indicator of their exercise performance

Response to the Letter by Rose et al

We would like to reply to the letter by Drs Rose, Keating, and Backx,1 in which they gave their response to our recent publication in Circulation Research .2 In this study, we introduced alignment of transplanted stem cells as a novel determinant of functional integration of these cells with native cardiac tissue. In this study, we used neonatal rat mesenchymal stem cells (MSCs), which differentiated into functional cardiac cells after coculture with neonatal rat cardiomyocytes (CMCs). In their letter, Rose et al raise the important question of whether MSCs can differentiate into functional CMCs.1 However, we demonstrated that neonatal rat MSCs do differentiate into functional CMCs. Although we were one of the first to address the issue of cell alignment and stem cell transplantation, cardiomyogenic differentiation of MSCs …

Psychiatric outcome of localized head injury in children.

Previous studies have shown a high prevalence of psychiatric disturbance in children with brain injury. Studies on localized lesions have suggested that injury to the young organism carries a better prognosis for recovery of function than injury at a later age. The present study was designed to investigate these phenomena systematically. A representative sample of children (n = 98) who had been hospitalized for treatment of a compound depressed fracture, associated with a dural tear and visible damage to the underlying cortex, was identified from the records of neurosurgical units throughout the United Kingdom. The children were aged between 3 months and 12 years at the time of injury and between 5 and 15 years at the time of examination. The interval between injury and examination varied but the sample was designed to include only children who had been injured at least two years before examination. The children were examined neurologically and psychometrically, a detailed account of their current psychiatric state was obtained from one or both parents, and their mental state was assessed in a standard psychiatric examination. Preliminary data are presented which relate psychiatric, educational and intellectual status at the time of examination to site and severity of injury, age at injury, and to a number of psychosocial variables.

Molecular profiles of the mouse postnatal development of the esophageal epithelium showing delayed growth start

Studies on molecular mechanisms of self-renewal in normal stem cells are required for understanding the cancer stem cell. Self-renewal in many kinds of normal stem cells might be accelerated in the growth of a young organism and in the repair of damaged tissue. This study examined whether the esophagus in growing neonates provides an experimental system for studies on epithelial stem cell renewal. The esophageal epithelium consists of 3 layers, from the luminal side to the bottom: the differentiated, epibasal and basal cell layers. The basal cell layer is known to contain the stem cells for the esophageal epithelium. This basic architecture is observed both in mice and humans. We investigated the basal cells in the mouse neonate by immunostaining with a basal cell marker, nerve growth factor receptor (Ngfr), and compared the basal cell content in the esophageal epithelium between mice and humans. A mouse esophageal epithelial cell primary culture system was developed for studies on the basal cell growth and keratinocyte differentiation, and microarray analysis was conducted for obtaining expression profiles of the basal cells. It was revealed that the growth of the esophageal epithelium begins from postnatal day 3, and that the timing is consistent with membrane localization of Ngfr in the basal cell. An increase in the basal cell number by Ngf treatment is observed in in vitro mouse esophageal epithelium cultures. Furthermore, mRNA overexpression of Pdgfrb encoding platelet derived growth factor receptor beta and Egfr encoding epidermal growth factor receptor is associated with the timing of the growth of the esophageal epithelium in the neonatal mice. This study provides a new experimental model for studies on the growth of the basal cells, which are considered to include the stem cells, and on the enlargement of the body size in young organisms.

Causal factors of acute gastroenteritis in infants and young children.

Respiratory, gastrointestinal and skin diseases represent the most common diseases in infants and young children. Causal factors of these diseases are important infectious agents and causes of pathological conditions in children, but they are also very important for their parents, as well as for people in their close environment. Greater incidence of infections in infants and young children can be explained in different ways. A cause can be insufficient maturity of their immune system, but also their exposure to infections within collective accommodations (cribs, nurseries, pre-school institutions), where they are, at the same time, exposed to a number of unknown agents. Today, a great emphasis is devoted to the ways and kinds of children's nutrition. The problem of relation between infected young organism and infectious agent itself, is also reflected in a long resistance and excretion of microorganisms in their exterior environment. It is well-known that microorganisms resist and excrete much longer in younger organisms, compared to adults, where their resistance and excretion is much shorter or very rare. Actually, adults have already formed protective immunity against particular infectious agents. It doesn't prevent infections in adults, colonization of pathogens, nor eventual development of disease. Established immunity can shorten the time necessary for excretion of microorganisms in their exterior environment and, if disease gets developed, it is of shorter duration and slower progress.

Prenatal experience and postnatal perceptual preferences: evidence for attentional-bias in bobwhite quail embryos (Colinus virginianus).

Previous studies have indicated that concurrent multimodal sensory stimulation can interfere with prenatal perceptual learning. This study further examined this issue by exposing 3 groups of bobwhite quail embryos (Colinus virginianus) to (a) no supplemental stimulation, (b) a bobwhite maternal call, or (c) a maternal call paired with a pulsating light in the period prior to hatching. Experiments differed in terms of the types of stimuli presented during postnatal preference tests. Embryos receiving no supplemental stimulation showed no preference between stimulus events in all testing conditions. Embryos receiving exposure to the unimodal maternal call preferred the familiar call over an unfamiliar call regardless of the presence or absence of pulsating light during testing. Embryos exposed to the call-light compound preferred the familiar call only when it was paired with the light during testing. These results suggest that concurrent multimodal stimulation does not interfere with prenatal perceptual learning by overwhelming the young organism's limited attentional capacities. Rather, multimodal stimulation biases what information is attended to during exposure and subsequent testing.

Atypical perinatal sensory stimulation and early perceptual development: insights from developmental psychobiology.

Comparative studies utilizing avian and mammalian embryos and neonates have proven particularly useful in exploring how alterations in sensory experience during the perinatal period can affect subsequent development. This article reviews research drawn from comparative developmental psychobiology and concludes that the effects of modified sensory stimulation on perceptual and behavioral development depend on several related factors, including the timing of stimulation relative to the developmental stage of the young organism, the overall amount of sensory stimulation provided or denied, and the type of sensory stimulation presented. Directions for future research on the care of the high-risk infant are discussed.

Pulmonary effects of inhaled ultrafine particles.

Recent epidemiological studies have shown an association between increased particulate urban air pollution and adverse health effects on susceptible parts of the population, in particular the elderly with pre-existing respiratory and cardiovascular diseases. Urban particles consist of three modes: ultrafine particles, accumulation mode particles (which together form the fine particle mode) and coarse mode particles. Ultrafine particles (those of < 0.1 micron diameter) contribute very little to the overall mass, but are very high in number, which in episodic events can reach several hundred thousand/cm3 in the urban air. The hypothesis that ultrafine particles are causally involved in adverse responses seen in sensitive humans is based on several studies summarized in this brief review. Studies on rodents demonstrate that ultrafine particles administered to the lung cause a greater inflammatory response than do larger particles, per given mass. Surface properties (surface chemistry) appear to play an important role in ultrafine particle toxicity. Contributing to the effects of ultrafine particles is their very high size-specific deposition when inhaled as singlet ultrafine particles rather than as aggregated particles. It appears also that ultrafine particles, after deposition in the lung, largely escape alveolar macrophage surveillance and gain access to the pulmonary interstitium. Inhaled low doses of carbonaceous ultrafine particles can cause mild pulmonary inflammation in rodents after exposure for 6 h. Old age and a compromised/sensitized respiratory tract in rodents can increase their susceptibility to the inflammatory effects of ultrafine particles significantly, and it appears that the aged organism is at a higher risk of oxidative stress induced lung injury from these particles, compared with the young organism. Results also show that ultrafine particle effects can be significantly enhanced by a gaseous co-pollutant such as ozone. The studies performed so far support the ultrafine particle hypothesis. Additional studies are necessary to evaluate mechanistic pathways of responses.

Ontogenetic constraints on neural and behavioral plasticity: evidence from imprinting and face processing.

This paper addresses the extent and limits on brain plasticity during development through the detailed study of imprinting in the domestic chick and the development of face processing in human infants. In both of these systems, evidence for constraints on plasticity is reviewed. The first source of constraint comes from the basic architecture of learning mechanisms that support plasticity. With regard to the chick, a specific "Hebbian" model based on the known neural circuitry of the region of the brain involved is presented and discussed. In human infants, a more abstract model inspired by cortical circuitry is mentioned. The second source of constraint comes from biases on the nature of the stimuli selected for attention by the young organism. Both in the chick and the human there is evidence for a subcortical brain system which orients their attention toward conspecifics, and particularly to their faces. It is argued that these systems tutor, or bias the input to, the more plastic learning systems.

Effect of social and hygienic factors on reproductive function of women

The dependence of the initiation of pregnancy and birth pathology on social, economic and hygienic factors is established. Using the three-factor dispersion analysis of qualitative signs the factors playing the leading part in the initiation of complications during pregnancy and in birth are revealed. The factors of industrial environment, and social and economic trouble are in the first group, the anatomic and physiologic peculiarities of young organism and bad social conditions are in the second group.