Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 8 de 8
Filtrar
Mais filtros










Base de dados
Intervalo de ano de publicação
1.
J Geriatr Cardiol ; 19(11): 876-893, 2022 Nov 28.
Artigo em Inglês | MEDLINE | ID: mdl-36561057

RESUMO

The autonomic nervous system plays an important role in the pathogenesis of cardiovascular diseases. With aging, autonomic activity changes, and this impacts the physiological reactions to internal and external signals. Both sympathetic and parasympathetic responses seem to decline, reflecting functional and structural changes in nervous regulation. Although some investigators suggested that both the sympathetic and parasympathetic activities were suppressed, others found that only the parasympathetic activity was suppressed while the sympathetic activity increased. In addition, cardiac innervation progressively diminishes with aging. Therefore, one may suggest that neuromodulation interventions may have different effects, and older age groups can express an attenuated response. This article aims to discuss the effect of device-based neuromodulation in different cardiovascular diseases, depending on the patient's age. Thus, we cover renal denervation, pulmonary artery denervation, baroreceptor activation therapy, vagus nerve stimulation, spinal cord stimulation, ganglionated plexi ablation for the management of arterial and pulmonary hypertension, heart failure, angina and arrhythmias. The results of many clinical studies appeared to be unconvincing. In view of the low rate of positive findings in clinical studies incorporating neuromodulation approaches, we suggest the underestimation of advanced age as a potential contributing factor to poorer response. Analysis of outcomes between different age groups in clinical trials may shed more light on the true effects of neuromodulation when neutral/ambiguous results are obtained.

2.
Biophys Rev ; 14(4): 985-1004, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-36124262

RESUMO

The paper presents the results of recent work at the Department of Biophysics of the Biological Faculty, Lomonosov Moscow State University on the kinetic and multiparticle modeling of processes in the photosynthetic membrane. The detailed kinetic models and the rule-based kinetic Monte Carlo models allow to reproduce the fluorescence induction curves and redox transformations of the photoactive pigment P700 in the time range from 100 ns to dozens of seconds and make it possible to reveal the role of individual carriers in their formation for different types of photosynthetic organisms under different illumination regimes, in the presence of inhibitors, under stress conditions. The fitting of the model curves to the experimental data quantifies the reaction rate constants that cannot be directly measured experimentally, including the non-radiative thermal relaxation reactions. We use the direct multiparticle models to explicitly describe the interactions of mobile photosynthetic carrier proteins with multienzyme complexes both in solution and in the biomembrane interior. An analysis of these models reveals the role of diffusion and electrostatic factors in the regulation of electron transport, the influence of ionic strength and pH of the cellular environment on the rate of electron transport reactions between carrier proteins. To describe the conformational intramolecular processes of formation of the final complex, in which the actual electron transfer occurs, we use the methods of molecular dynamics. The results obtained using kinetic and molecular models supplement our knowledge of the mechanisms of organization of the photosynthetic electron transport processes at the cellular and molecular levels.

3.
Viruses ; 14(5)2022 04 21.
Artigo em Inglês | MEDLINE | ID: mdl-35632601

RESUMO

Modern metagenomic approaches enable the effective discovery of novel viruses in previously unexplored organisms. Termites are significant ecosystem converters and influencers. As with the majority of tropical forest insects, termites are studied insufficiently, and termite virome remains especially understudied. Here, we studied the virome of lichenophagous and mycophagous termites (Hospitalitermes bicolor, Macrotermes carbonarius and Odontotermes wallonensis) collected in the Cat Tien National Park (Vietnam). We assembled four full genomes of novel viruses related to Solemoviridae, Lispiviridae, Polycipiviridae and Kolmioviridae. We also found several contigs with relation to Chuviridae and Deltaflexiviridae that did not correspond to complete virus genomes. All the novel viruses clustered phylogenetically with previously identified viruses of the termites. Deltaflexi-like contigs were identified in the fungi-cultivating M. carbonarius and showed homology with viruses recently discovered in the edible basidiomycete mushrooms.


Assuntos
Isópteros , Vírus de RNA , Animais , Ecossistema , Florestas , Vietnã , Viroma
4.
Proc Natl Acad Sci U S A ; 117(49): 31249-31258, 2020 12 08.
Artigo em Inglês | MEDLINE | ID: mdl-33229550

RESUMO

For species to stay temporally tuned to their environment, they use cues such as the accumulation of degree-days. The relationships between the timing of a phenological event in a population and its environmental cue can be described by a population-level reaction norm. Variation in reaction norms along environmental gradients may either intensify the environmental effects on timing (cogradient variation) or attenuate the effects (countergradient variation). To resolve spatial and seasonal variation in species' response, we use a unique dataset of 91 taxa and 178 phenological events observed across a network of 472 monitoring sites, spread across the nations of the former Soviet Union. We show that compared to local rates of advancement of phenological events with the advancement of temperature-related cues (i.e., variation within site over years), spatial variation in reaction norms tend to accentuate responses in spring (cogradient variation) and attenuate them in autumn (countergradient variation). As a result, among-population variation in the timing of events is greater in spring and less in autumn than if all populations followed the same reaction norm regardless of location. Despite such signs of local adaptation, overall phenotypic plasticity was not sufficient for phenological events to keep exact pace with their cues-the earlier the year, the more did the timing of the phenological event lag behind the timing of the cue. Overall, these patterns suggest that differences in the spatial versus temporal reaction norms will affect species' response to climate change in opposite ways in spring and autumn.


Assuntos
Adaptação Fisiológica/fisiologia , Mudança Climática , Monitoramento Ambiental , População , Animais , Ecossistema , Estações do Ano , Temperatura , U.R.S.S.
5.
Wiad Lek ; 73(9 cz. 2): 2040-2043, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33148856

RESUMO

OBJECTIVE: The aim: To review scientific literature dealing with evaluation of medical rehabilitation effectiveness and quality in the world. PATIENTS AND METHODS: Materials and methods: Review and generalization of scientific literature on the criteria of evaluation of medical rehabilitation quality in advanced industrialized societies. CONCLUSION: Conclusions: Despite differences in the structure of medical rehabilitation in world societies, the end point is similar - assessment of quality of life of a sick person, measured by various criteria and standards. This experience is of great value for the development of national system of rehabilitation services.


Assuntos
Qualidade de Vida , Países Desenvolvidos , Humanos , Controle de Qualidade
6.
J Cardiovasc Transl Res ; 13(6): 891-893, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-32378161

RESUMO

We aimed to determine if non-invasive electrical spinal cord stimulation (NIE-SCS) is associated with acute changes in systemic and pulmonary hemodynamics and cardiac electrophysiology at rest. Nine subjects without structural heart disease referred for catheter ablation of cardiac arrhythmia were included. NIE-SCS was performed in each patient at vertebral levels T1, T7, and T11. Higher systolic BP (BPs) was detected during T1 NIE-SCS as compared with baseline (147.9 ± 22.5 vs 135.4 ± 17.4 mmHg; P = 0.02). Atrioventricular nodal effective refractory period (AVN ERP) was shorter during stimulation at T1 and T7, when compared with baseline values (baseline 303.3 ± 15.0 vs 272.0 ± 19.2 for T1 vs 278.0 ± 8.3 ms for T7; P < 0.05). NIE-SCS at the T1 level is associated with an elevation of BPs. NIE-SCS at the T1 and T7 levels shortens AVN ERP. Further studies are needed for the evaluation of chronic effects.


Assuntos
Potenciais de Ação , Nó Atrioventricular/inervação , Sistema Nervoso Autônomo/fisiopatologia , Pressão Sanguínea , Sistema Cardiovascular/inervação , Estimulação da Medula Espinal , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Projetos Piloto , Período Refratário Eletrofisiológico , Vértebras Torácicas , Fatores de Tempo
8.
Sci Data ; 7(1): 47, 2020 Feb 11.
Artigo em Inglês | MEDLINE | ID: mdl-32047153

RESUMO

We present an extensive, large-scale, long-term and multitaxon database on phenological and climatic variation, involving 506,186 observation dates acquired in 471 localities in Russian Federation, Ukraine, Uzbekistan, Belarus and Kyrgyzstan. The data cover the period 1890-2018, with 96% of the data being from 1960 onwards. The database is rich in plants, birds and climatic events, but also includes insects, amphibians, reptiles and fungi. The database includes multiple events per species, such as the onset days of leaf unfolding and leaf fall for plants, and the days for first spring and last autumn occurrences for birds. The data were acquired using standardized methods by permanent staff of national parks and nature reserves (87% of the data) and members of a phenological observation network (13% of the data). The database is valuable for exploring how species respond in their phenology to climate change. Large-scale analyses of spatial variation in phenological response can help to better predict the consequences of species and community responses to climate change.


Assuntos
Biota , Mudança Climática , Bases de Dados Factuais , Quirguistão , República de Belarus , Federação Russa , Estações do Ano , Ucrânia , Uzbequistão
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...