Peculiarities of Neurohormonal Modulation of Memory and Learning Processes in Young and Old Monkeys <Emphasis Type="Italic">Macaca mulatta</Emphasis>

Comparative data are presented about peculiarities of neurohormonal regulation of the memory and learning processes in young and old monkeys Macaca mulatta. It is shown that the hypothalamic neurohormones, vasopressin and thyroliberine, produce on the whole a unidirectional facilitating effect on the inherited and simple forms of the nervous activity in young and old animals. It is established that vasopressin, thyroliberine, and ACTH_4–10 participate differently in regulation and compensation of disturbed higher nervous functions in old monkeys. The compensatory effects of vasopressin are more pronounced at intranasal administration of its ultrasmall (0.01 jg/kg) doses. The thyroliberine administration had the longer and more expressed disinhibition effect on the conditional reflex memory in old monkeys, as compared with young ones. The question is discussed about different effects of vasopressin and thyroliberine on the higher nervous functions in young and old monkeys from the point of view of cytoarchitectonic changes in the neocortex and of immunohistochemical changes in the hypothalamus nuclear structures.     

Selank-induced normalizing effects on the integrative brain activity and biogenic amine level disorders due to antenatal hypoxia

The effects of Selank synthetic analog of Tuftsin, representing the heptapeptide forming Thr-Lys-Pro-Arg-Pro-Gly-Pro, on behavior and serotonin/noradrenalin concentrations in brain were investigated in adult rats exposed to hypoxia during 14-16 days of gestation. It was revealed that injection of Selank (300 mkg/kg, i/p) increased 2--3-fold (p < 0.01) the sensory attention, facilitated 1.5-fold the learning capacity (p < 0.01), normalized exploratory activity in the open field and hole board, and recovered the balance of serotonergic and noradrenergic brain system activity. The data obtained demonstrate the possibility of Selank to compensate for long-lasting negative effects of antenatal hypoxia on integrative brain activity and brain monoamine level.     

Optimizing action of synthetic peptide Selank on active avoidance conditioning test in rats

The action of a synthetic peptide Selank on learning and memory in active avoidance conditioning test was studied in rats with initially low learning ability and normal animals. The peptide was administered repeatedly 15 min prior the training session (4 days). The effect of Selank (300 micrograms/kg) was compared to that of Pyracetam (400 mg/kg). Selank was found to significantly improve learning in rats with low level ability even after a single administration on the first day of training session. The effect progressively increased with repeated Selank treatment: the total numbers of reactions and correct reactions increased, and the number of errors decreased (p < 0.05). In normal rats, the effect was maximal on the third day of treatment and training, i.e., after the completed initial consolidation. Some distinguishing features were revealed in the dynamics of activatory effects of Selank and Pyracetam. These data together with the evidence for ansiolytic effect of Selank show that this drug is promising for optimization of mnestic functions under conditions of high emotional stress.     

Compensation in behavioral disorders in rats receiving 5,7-DHT neonatally and by transplantation of embryonic raphe nucleus tissue

In 62 male Wistar rats the influence was studied of the transplanted embryonal tissue of raphe nuclei (NR) on the mechanisms of compensation of disturbances of exploratory activity, sensory attention, learning and emotional reactivity induced by neonatal injection of 5,7-DHT. In histochemical studies by Falk-Hillarp method the presence of yellow fluorescence confirmed the specificity of transplanted 5-HT neurones. It is found that NR transplantation causes in animals after 3 months recovery of orienting reaction to sensory stimuli, reduces rats reactivity in the open field, restores the ability to discrimination of emotionally positive influence, disturbed by neonatal injection of 5,7-DHT. The obtained data show the possibility of compensation of behaviour disturbances caused by chronic deprivation of 5-HT system activity by transplantation in the neocortex parenchyma of the embryonal tissue, containing serotoninergic neurones.     

Biological and psychological rhythms: An integrative approach to rhythm disturbances in autistic disorder

Biological rhythms are crucial phenomena that are perfect examples of the adaptation of organisms to their environment. A considerable amount of work has described different types of biological rhythms (from circadian to ultradian), individual differences in their patterns and the complexity of their regulation. In particular, the regulation and maturation of the sleep–wake cycle have been thoroughly studied. Its desynchronization, both endogenous and exogenous, is now well understood, as are its consequences for cognitive impairments and health problems. From a completely different perspective, psychoanalysts have shown a growing interest in the rhythms of psychic life. This interest extends beyond the original focus of psychoanalysis on dreams and the sleep–wake cycle, incorporating central theoretical and practical psychoanalytic issues related to the core functioning of the psychic life: the rhythmic structures of drive dynamics, intersubjective developmental processes and psychic containment functions. Psychopathological and biological approaches to the study of infantile autism reveal the importance of specific biological and psychological rhythmic disturbances in this disorder. Considering data and hypotheses from both perspectives, this paper proposes an integrative approach to the study of these rhythmic disturbances and offers an etiopathogenic hypothesis based on this integrative approach.     

Lowland tapirs facilitate seed dispersal in degraded Amazonian forests

The forests of southeastern Amazonia are highly threatened by disturbances such as fragmentation, understory fires, and extreme climatic events. Large‐bodied frugivores such as the lowland tapir (Tapirus terrestris) have the potential to offset this process, supporting natural forest regeneration by dispersing a variety of seeds over long distances to disturbed forests. However, we know little about their effectiveness as seed dispersers in degraded forest landscapes. Here, we investigate the seed dispersal function of lowland tapirs in Amazonian forests subject to a range of human (fire and fragmentation) and natural (extreme droughts and windstorms) disturbances, using a combination of field observations, camera traps, and light detection and ranging (LiDAR) data. Tapirs travel and defecate more often in degraded forests, dispersing much more seeds in these areas [9,822 seeds per ha/year (CI_95% = 9,106; 11,838)] than in undisturbed forests [2,950 seeds per ha/year (CI_95% = 2,961; 3,771)]. By effectively dispersing seeds across disturbed forests, tapirs may contribute to natural forest regeneration—the cheapest and usually the most feasible way to achieve large‐scale restoration of tropical forests. Through the dispersal of large‐seeded species that eventually become large trees, such frugivores also contribute indirectly to maintaining forest carbon stocks. These functions may be critical in helping tropical countries to achieve their goals to maintain and restore biodiversity and its ecosystem services. Ultimately, preserving these animals along with their habitats may help in the process of natural recovery of degraded forests throughout the tropics. Abstract in Portuguese is available with online material.     

Semax and Selank Inhibit the Enkephalin-Degrading Enzymes of Human Serum

Dose-dependent effect of synthetic heptapeptides Semax (Met-Glu-His-Phe-Pro-Gly-Pro) and Selank (Thr-Lys-Pro-Arg-Pro-Gly-Pro) on the enkephalin-degrading enzymes of human serum was demonstrated. The inhibitory effects of Semax (IC₅₀10 M) and Selank (IC₅₀20 M) are more pronounced than that of puromycin (IC₅₀10 mM), bacitracin, and some other inhibitors of peptidases. Beside the heptapeptides, their pentapeptide fragments also possessed an inhibitory effect; tri-, tetra- and hexapeptide fragments did not display such an effect. As the above enzymes take part in degradation of not only enkephalins but also other regulatory peptides, it can be assumed that one of the mechanisms of biological activity of Semax and Selank is related to this inhibitory activity of theirs.     

On methods of neurorehabilitation of patients with focal brain lesions

Direction of restoration of speech and other higher psychic functions in neurorehabilitation of patients with focal brain lesions is considered. The proposed approach is illustrated by procedures of recovery of speech, writing, count, and visual gnosis. A clinical case is presented to show how the rehabilitative work is performed. The originality of this approach consists in use of systemic properties of the recovered function. The fundamental principle is based on consideration of structural regularities of lingual or any other restoration functions, which are sufficiently established in the adults experience. It is proposed to perform the rehabilitative work as if bypassing the central defect, which represents a gentler and less tedious process for patients. Efficiency of the rehabilitation is discussed with involvement of studies in the field of structure of disturbances and mechanisms of compensation of psychic functions during local brain lesionsTranslated from Zhurnal Evolyutsionnoi Biokhimii i Fiziologii, Vol. 40, No. 5, 2004, pp. 469–475.Original Russian Text Copyright © 2004 by Khrakovskaya.To the 100-Anniversary of N. N. Traugott     

The effect of cholinergic substances on the mechanisms of visual recognition in monkeys

In monkeys (Macaca mulatta) instrumental reflex was elaborated with differentiation of black-and-white and colour visual stimuli in condition of systemic administration of pharmacological preparations selectively influencing the functional state of cholinergic brain structures. Differentiation of black-and-white and colour stimuli is not disturbed by atropine (0.1 mg/kg) and amizile (up to 1.5 mg/kg) injections; at greater doses frustration of the instrumental reflex takes place. Differentiation of black-and-white and colour stimuli is disturbed at injection of various doses of antidepressant phthoracizine: 5 mg/kg and 7 mg/kg, respectively. These disturbances are restored by the injection of definite doses of galantamine; for correction of colour differentiation a greater dose is required. The obtained data point to differences in neurophysiological and neurochemical processes responsible for black-and-white and colour vision.     

森林干扰生态研究

陆地上80％的生态系统都已受到了来自人类和自然的各种干扰,森林生态系统也不例外．在各种干扰作用下,尤其是人类不合理的干扰导致世界范围内的森林退化／衰退已成为一个十分严峻的事实,因此,以维持、恢复森林生态系统固有的多种功能为基础,实现高效、稳定、可持续就成为经营森林生态系统的总目标．随着干扰的加剧,近年来生态学界更加关注的是“受干扰”生态系统的研究．干扰对森林生态系统主要生态过程的影响以及森林生态系统对干扰的响应等问题,已成为森林生态研究领域的国际前沿与热点．因此,系统地研究干扰条件下森林生态系统的生态过程,并在此基础上确立干扰森林的经营理论与技术,对中国天然林资源保护等林业工程实施及国家生态安全建设具有重要的科学和现实意义．本文在广泛收集国内外有关森林干扰研究结果的基础上,总结了森林干扰的基本概念,分析了干扰与森林经营的关系,探讨了森林干扰研究领域所涉及的内容和关注的基础问题,提出了森林干扰生态研究的主要内容与方向,对今后干扰森林生态研究和中国天然林保护等林业工程建设具有参考价值．     

Tree Species Composition and Diversity at Different Levels of Disturbance in Popa Mountain Park,Myanmar

Tropical forests are highly threatened by human activities, even within the protected areas that have been established to conserve biodiversity. Human activities may have different degrees of impact on vegetation structure, composition and diversity. Some studies have measured direct evidence of human activities in forming disturbance gradients, while others have quantified canopy cover as a proxy for disturbance. When measurement is confined to human activities, disturbance may be underestimated in areas of poor canopy cover where forest degrading activities have ceased. Where measurements are restricted to canopy cover, disturbance may be underestimated in areas of extensive canopy cover that may have been subject to past disturbances, and overestimated for areas where canopy cover is naturally sparse. Combining indicators of past and present disturbances is therefore necessary to examine the full spectrum of human disturbances. Forest vegetation in Popa Mountain Park, Myanmar was surveyed and classified into three levels of disturbance—undisturbed, medium disturbed and highly disturbed—derived from evidence of cutting and canopy cover. The forests are second or third growth after clearing for agriculture in the early 20th century. All trees with ≥10 cm diameter at breast height in 168 sample plots (10 m × 10 m) were identified and measured. Density, basal area and diversity decreased and dominance rose when disturbance increased. Canonical correspondence analysis (CCA) clearly discriminated three forest stands and CCA axes were significantly correlated to soil moisture, soil nitrogen, elevation, slope, aspect, distance from park boundary and distance from villages. Abstract in Myanmar is available at http://www.blackwell‐synergy.com/loi/btp .     

Repeat disturbances have cumulative impacts on stream communities

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Salt leaching leads to drier soils in disturbed semiarid woodlands of central Argentina

Disturbances in semiarid environments have revealed a strong connection between water, salt and vegetation dynamics highlighting how the alteration of water fluxes can drive salt redistribution process and long-term environmental degradation. Here, we explore to what extent the reciprocal effect, that of salt redistribution on water fluxes, may play a role in dictating environmental changes following disturbance in dry woodlands. We assessed salt and water dynamics comparing soil-solution electrical conductivity, chloride concentration, soil water content (SWC) and soil matric and osmotic water potential (Ψ_m, Ψ_os) between disturbed and undisturbed areas. A large pool of salts and chlorides present in undisturbed areas was absent in disturbed plots, suggesting deep leaching. Unexpectedly, this was associated with slight but consistently lower SWC in disturbed versus undisturbed situations during two growing seasons. The apparent paradox of increased leaching but diminishing SWC after disturbance can be explained by the effect of native salt lowering Ψ_os enough to prevent full soil drying. Under disturbed conditions, the onset of deep drainage and salt leaching would raise Ψ_os allowing a decline of Ψ_m and SWC. Soil water storage seems to be modulated by the presence (under natural conditions) and partial leaching (following selective shrub disturbance) of large salt pools. This counterintuitive effect of disturbances may be important in semiarid regions where deep soil salt accumulation is a common feature. Our results highlight the importance of water–salt–vegetation coupling for the understanding and management of these systems.     

Recombinant human Hsp70 protects against lipoteichoic acid-induced inflammation manifestations at the cellular and organismal levels

It has been previously reported that pretreatment with exogenous heat shock protein 70 (Hsp70) is able to protect cells and animals from the deleterious effects of bacterial lipopolysaccharide (LPS) produced by Gram-negative bacteria. However, the effects of Hsp70 pretreatment on lipoteichoic acid (LTA) challenge resulted from Gram-positive bacteria infection have not been fully elucidated. In this study, we demonstrated that preconditioning with human recombinant Hsp70 ameliorates various manifestations of systematic inflammation, including reactive oxygen species, TNFα, and CD11b/CD18 adhesion receptor expression induction observed in different myeloid cells after LTA addition. Therefore, exogenous Hsp70 may provide a mechanism for controlling excessive inflammatory responses after macrophage activation. Furthermore, in a rat model of LTA-induced sepsis, we demonstrated that prophylactic administration of exogenous human Hsp70 significantly exacerbated numerous homeostatic and hemodynamic disturbances induced by LTA challenge and partially normalized the coagulation system and multiple biochemical blood parameters, including albumin and bilirubin concentrations, which were severely disturbed after LTA injections. Importantly, prophylactic intravenous injection of Hsp70 before LTA challenge significantly reduced mortality rates. Thus, exogenous mammalian Hsp70 may serve as a powerful cellular defense agent against the deleterious effects of bacterial pathogens, such as LTA and LPS. Taken together, our findings reveal novel functions of this protein and establish exogenous Hsp70 as a promising pharmacological agent for the prophylactic treatment of various types of sepsis.     

Comparative Study of Neurochemical Compensation of Disturbed Brain Functions in Mammals

In a comparative row of mammals (hedgehogs, rabbits, monkeys), the role of the opioid neuropeptide Met-encephalin (ME) and the hypothalamic neurohormone vasopressin (VP) was studied in possibility of compensation of disturbed higher nervous functions in organic and functional pathologies of the higher nervous activity. Administration of ME and VP under conditions of destruction of neocortex in hedgehogs was found to restore predominantly congenital forms of the nervous activity. In rabbits, on administration of VP, a tendency is revealed for restoration of acquired forms of the nervous activity; however, it is of a limited character. On administration of ME and VP under conditions of functional pathology a similar regularity in restoration of disturbed higher nervous functions is observed. Injection of ME and VP to hedgehogs produced a more pronounced and longer effect on unconditioned reflexes. The effect of low doses of VP on HNA is of short-term, generally facilitating character. In rabbits, on the background of VP, the memory processes (trace conditioned responses) are briefly restored and are enhanced. In monkeys, the effect of ME and VP on acquired forms of the nervous activity and on various functional systems is of differential character. The VP compensatory effects are more pronounced after administration of low VP doses. The effects of ME and VP on congenital forms of the nervous activity are negligible. The established regularities are discussed and interpreted from the viewpoint of the concepts postulated by A.I. Karamyan about evolution of the compensatory brain activity, evolution of neocortex, and an increase of its neuroplasticity.     

Ecosystem functions in degraded riparian forests of southeastern Kenya

Species community structures shape ecosystem functions, which are mostly stronger pronounced in intact than in degraded environments. Riparian forests in semiarid Africa provide important habitats for endangered plant and animal species and provide various ecosystem functions, that is, services to people settling along these streams. Most of these riparian forests are severely disturbed by human activities and dominated by invasive exotic plant species in the meanwhile. Thus, ecosystem functions are negatively influenced. While most studies have analyzed a specific metric to measure the degree of ecosystem function, little is known about how strongly different ecosystem functions respond to anthropogenic disturbances in parallel. In this study, we analyzed a set of four proxies of ecosystem functions, ground‐dwelling arthropod abundances, pollination, seed dispersal, and predation, along a highly disturbed riparian forest in southeastern Kenya. We assessed the land cover and land use manually and with an Unmanned Aerial Vehicle. Our data show that ecosystem functions respond differently to vegetation cover, human disturbances, and the availability of the invasive exotic shrub Lantana camara. The occurrence of representatives from the groups Saltatoria and Formicidae profits from heterogeneous habitat structures and natural riparian forest, while representatives of the Araneae profit from high proportion of agricultural fields. In general, predation is higher in mixed land use and natural riparian forest, while pollination and seed dispersal showed no significant trend in regard on land coverage. Along with this, predation also increased with rising proportion of natural riparian forest, while the proportion of agricultural land negatively affects predation, but in parallel showed a slightly significant positive trend with seed dispersal. Human disturbances and the occurrence of the invasive exotic L. camara shrub did not significantly affect our metrics of ecosystem functioning, except of the negative impact of human disturbances on pollinators. In conclusion, our results underpin that ecosystem functions respond highly variable and individually to environmental changes.     

Effect of new synthetic anxiolytic selank on gastric wall blood flow and mesenteryc lymphatic vessels contractility in anesthetized rats

The influence of a new heptapeptide Selank on microcirculation in anesthetized white rats was investigated. Selank (Thr-Lys-Pro-Arg-Pro-Gly-Pro) is a new synthetic anxiolytic which exerts obvious antiulcerogenic action and promotes healing of experimental ulcers. Action of the peptide on gastric blood flow in the stomach by using the method ofhydrogenic clearance and Selank action on mesenteric lymphatic contractility by microscopical observation in situ, were studied. Selank fail to influence basal gastric blood flow but it can normalize blood flow reduced by indomethacin. The study of dose-depended of Selank effect on lymphatic vessels contractility showed that its low concentration (10(-12)--10(-14) M) enhanced amplitude and increase frequency of lymphatic vessel contractions which indicates an enhancement of lymphatic flow. The high doses of peptide (10(-6)--10(-10) M) also augmented the contraction amplitude but decreased its frequency. The maintenance of adequate blood flow and lymphatic vessel contractility can be one of the mechanisms of the Selank antiulcerogenic properties.     

Complex behavior forms in the lower monkeys in the process of identification of quantitative signs of visual stimuli

Complex behavior forms and the ability of monkeys to recognize and to compare by identity the two-dimensional images and three-dimensional objects of various colors in the amount from 5 to 9 were studied. The study was carried out on two species of the lower monkeys of different levels of phylogenetic development: on rhesus monkeys (Macaca mulatta) and on brown capuchins (Cebus apella). It has been established that the representatives of the studied monkey species are able to differentiate large counted multitudes of two-dimensional (images of squares) and three-dimensional (objects of round shape) stimuli of red, yellow, and green colors in different quantitative ratios—from 5 to 9 at solving modifications of task of the type “choice by the sample.” In the course of learning, species-related differences of the monkeys’ behavior are revealed. The brown capuchins managed solving all tasks and their combinations better than rhesus monkeys. The obtained data indicate the capability for recognition of counted multitudes (from 5 to 9) regardless of color of the stimuli and the existence of quantitative notions of the idea of “quantity” in the lower monkeys.     

Vegetation and climate reconstructions on different time scales in China: a review of Chinese palynological research

This paper reviews vegetation and climate reconstructions for different time scales based on palynological studies in China. It discusses examples of significant developments in palynological research topics within China: (1) Modern pollen—a modern pollen database (East Asia Surface Pollen Database) has been established through the collaboration of Chinese palynologists. Based on these data, modern pollen distributions and their quantitative relationship with vegetation and climate have been thoroughly studied. (2) Pre-Quaternary vegetation and climate dynamics—scientists have mapped pollen and palaeobotanical data from the Palaeogene. The vegetation distributions confirm a north–south zonal pattern during the Palaeogene that changed to an east–west monsoonal pattern during the Miocene and Pliocene. These results provide key evidence for understanding monsoon evolution. (3) Late-Quaternary vegetation—biome reconstructions based on fossil pollen data show spatial and temporal changes in vegetation since the Last Glacial Maximum, permitting a better understanding of climate change across China. (4) Quantitative climate reconstructions—some reconstructions have successfully detected Holocene climate variability thereby providing insights into monsoon history. At present, there are no comprehensive spatial reconstructions. Major possible future developments should focus on: (1) long-term vegetation reconstructions from lakes to study Asian monsoon dynamics at orbital scales; (2) quantitative reconstructions of vegetation and climate change to help stronger integration with palaeoclimate models and dynamic vegetation models; (3) land-cover and land-use change across China over the last 6,000 years to understand human impacts and provide empirical data for climate modellers; and (4) integration of pollen data with vegetation and climate modelling to understand the CO₂-vegetation relationship and climate dynamics.