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Discontinuous and continuous transitions of collective behaviors in living systems 被引量:1
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作者 Xu Li Tingting Xue +6 位作者 Yu Sun Jingfang Fan Hui Li Maoxin Liu Zhangang Han Zengru Di Xiaosong Chen 《Chinese Physics B》 SCIE EI CAS CSCD 2021年第12期160-166,共7页
Living systems are full of astonishing diversity and complexity of life.Despite differences in the length scales and cognitive abilities of these systems,collective motion of large groups of individuals can emerge.It ... Living systems are full of astonishing diversity and complexity of life.Despite differences in the length scales and cognitive abilities of these systems,collective motion of large groups of individuals can emerge.It is of great importance to seek for the fundamental principles of collective motion,such as phase transitions and their natures.Via an eigen microstate approach,we have found a discontinuous transition of density and a continuous transition of velocity in the Vicsek models of collective motion,which are identified by the finite-size scaling form of order-parameter.At strong noise,living systems behave like gas.With the decrease of noise,the interactions between the particles of a living system become stronger and make them come closer.The living system experiences then a discontinuous gas-liquid like transition of density.The even stronger interactions at smaller noise make the velocity directions of the particles become ordered and there is a continuous phase transition of collective motion in addition. 展开更多
关键词 living systems phase emergence phase transitions eigen mircostate
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The Predictive Potential of the Kinetic Model of Aging of Living Systems in Demography 被引量:1
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作者 Alexander Alexandrovich Viktorov Viacheslav Alexandrovich Kholodnov 《Journal of Geriatric Medicine》 2019年第2期1-7,共7页
An original mathematical model,previously tested by the authors on other non-demographic objects,is proposed for describing and forecasting demographic systems—the population of the countries of the World using the e... An original mathematical model,previously tested by the authors on other non-demographic objects,is proposed for describing and forecasting demographic systems—the population of the countries of the World using the examples of the USA,China and Russia,as well as the number of mice in the“mouse paradise”experiment of the American scientist John Calhoun.The proposed approach allows us to describe the stages and features of this dynamics:population growth in the USA,growth and possible decrease in the population in China,loss of a part of the population of the Russian Empire and the USSR due to two world wars and the collapse of the USSR,biological degradation of the“mouse paradise”up to its complete extinction.The use of the kinetic model of aging of various types of living systems to predict the development of the number of demographic systems is based on the assumptions that the aging and development processes are related to each other and have the same statistical regularity,reflecting the fractal principle of Nature-the unity of structure and function.The results obtained suggest that a person,a population of the World,humanity and other biological species develop and simultaneously age like each other under the conditions of the always existing syndrome of general adaptation(stress)and according to the same pattern corresponding to the mathematical model proposed here. 展开更多
关键词 Model Kinetic theory Dynamics POPULATION living system General adaptation syndrome Stress
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Informational Structure of the Living Systems: From Philosophy to Informational Modeling 被引量:7
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作者 Florin Gaiseanu 《Journal of Philosophy Study》 2020年第12期795-806,共12页
In this paper,there are discussed the informational functions of the living structures,analyzing the properties of the simplest eukaryotic cell as an example of a structural unit of the living unicellular and multicel... In this paper,there are discussed the informational functions of the living structures,analyzing the properties of the simplest eukaryotic cell as an example of a structural unit of the living unicellular and multicellular systems.The initiation of this analysis starts from an older example of an imaginary mechanism,particularly that described by the Maxwell’s demon experiment,which along the history of the information development concepts accompanied the philosophic vision on the structuration of matter and of the living entities,showing that these are actually the result of the intervention of information on the matter available substrate.Particularly,it is shown that the deoxyribonucleic acid(DNA)structure is appropriate to store a large quantity of structural information,allowing the transfer of this information by transcription and translation mechanisms to proteins,which act as(re)structuration/transmission informational agents,or the generation of a new cellular daughter structure by a replication process.On the basis of the theory of information in communication channels,applicable also in biological systems,it was discussed the followed line for the evaluation of the quantity of structural information in various cells,demonstrating the evolution of organism complexity by the increase of the structural information quantity from unicellular(bacterium)to human cell.Applying a natural strategy of entropy lowering mainly by heat elimination,folding protein structuration and compartmentalization on the evolutionary scale,the living structures act as dynamic entities assuring their self-organizational structure by a permanent change of matter,energy and information with the environment in an efficient way,following a negative entropic process by internal structuration,similarly with Maxwell’s demon work.It is shown that to assure such a communication with external and internal intracellular structure,it was necessary the development of an own info-operational system of communication and decision,in which the operational“Yes/No”decisional binary(Bit)unit is essential.These revolutionary results show that the cell unit complies with the similar informational functions like the multicellular structure of the human body,organized in seven-type informational components,allowing the informational modeling of the activity of the living biologic structures and the opening of a shortcutting way to mimic the biologic functions in artificial cells. 展开更多
关键词 information/matter structuration/destructuration matter-related information negentropy/information non-living/living structures informational system of the living structures
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The role of nickel(II) on the homochirality of amino acids in living systems
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作者 Awni Khatib Fathi Aqra 《Chinese Chemical Letters》 SCIE CAS CSCD 2010年第1期113-116,共4页
The origin of homochirality in living organisms is controversial,stands out of being particularly important and a question which is still not satisfactorily answered.A mental picture of sequence of events that is thou... The origin of homochirality in living organisms is controversial,stands out of being particularly important and a question which is still not satisfactorily answered.A mental picture of sequence of events that is thought to have preceded the existence of chirality in molecules is described.A chemical model to mimic the original abiotic conditions in an attempt to explain the preference of homochirality in living systems was tried.The effect which might have influenced this preference is presented.The surpri... 展开更多
关键词 HOMOCHIRALITY living organisms Chiral preference
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Fluctuations Hypothesize the New Explanation of Meridians in Living Systems
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作者 Gyula Peter Szigeti Andras Szasz 《Open Journal of Biophysics》 2019年第1期51-69,共19页
Biosystems are complex. Their physiology is well-controlled with various negative feedback signals and processes, it describes by opposite interfering effects which are characterized in the Eastern philosophy by Yin-Y... Biosystems are complex. Their physiology is well-controlled with various negative feedback signals and processes, it describes by opposite interfering effects which are characterized in the Eastern philosophy by Yin-Yang (Y-Y) pairs. Y-Y pairs could be described by the promoter-suppressor pairs in a wide range of physiologic signals creating the homeostasis of the complex system. This type of control appears as fluctuations from the average (mean) value of the signal. The mean carries an ineluctable fluctuation (called pink-noise or 1/f noise). All signals in homeostasis have equal entropy (SE = 1.8), which is the character of the complex equilibrium. The various controlling opposite signals (Y-Y) have different time-scales which change by aging. The processes with smaller time-scale are degraded by aging, but the pink-noise ensures that the deviations of the signals of the healthy homeostatic system remain constant. Meridians are connected to the general transport systems that combined the material and the information transport with the considerable transport networks, like blood, lymph, nerve, cell-junctions, mesenchymal “ground substance” cytoskeletons. The meridians in this meaning only virtual line averaged from multiple realized paths to connect two acupuncture points by the material, energy and information transport processes. The meridian network is designed by various coupling points (acupoints), which could be perturbed by actuating stimulus. Our objective is to describe the meridian system from complexity point of view. 展开更多
关键词 Pink-Noise Complexity living system MERIDIANS ACUPOINTS HOMEOSTASIS
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Reaction of water and living systems under the chronic effect of ionized radiation in low doses
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作者 Igor Borisovich Ushakov Vladimir Vladimirovich Tsetlin Svetlana Stepanovna Moisa 《Journal of Biomedical Science and Engineering》 2012年第12期771-778,共8页
It is represented the review about the effect of low doses of ionized radiation on different types of biological objects (Japanese quail embryos, Aspergillus niger, Spirostomum ambiguum Ehrbg., mezenchim stem cells of... It is represented the review about the effect of low doses of ionized radiation on different types of biological objects (Japanese quail embryos, Aspergillus niger, Spirostomum ambiguum Ehrbg., mezenchim stem cells of mice bone brain, dry seeds of the highest plants, blood lymphocytes of pilots and cosmonauts) and water medium. In model experiments under the chronic ionized radiation in doses comparable with the doses of ionized radiation inside the orbital space stations and during the flight in interplanetary space was shown alike with morphological deviations (Japanese quail embryos, Aspergillus niger), the phenomenon of radiation hormezis (Aspergillus niger, mezenchim stem cells), the increasing of the germination of seeds, the decreasing of spontaneous motion activity of spirostoms and DNA damage, chromosome aberrations and the increased radio-sensitivity to adding radiation load in blood lymphocytes. These data testified the fact that the definite factor of ionized radiation effect is the changing of water medium state. Thus under the interplanetary cosmic flight and long stay on the orbit in the region of magnetosphere the studying kinds of radiation first effected on the water medium of organism as a result morpho-functional structures were changed. 展开更多
关键词 Ionized RADIATION REACTION of Water living systems Low Doses ORBITAL SPACE STATION
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Why Linear Thermodynamics Does Describe Change of Entropy Production in Living Systems?
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作者 Alexey A. Zotin 《Natural Science》 2014年第7期495-502,共8页
We propose a hypothesis according to which there is a hierarchy of included steady states in living systems. Each steady state is not stable and exists only in a certain frame of time, named characteristic time. Evolu... We propose a hypothesis according to which there is a hierarchy of included steady states in living systems. Each steady state is not stable and exists only in a certain frame of time, named characteristic time. Evolution of system to any steady state leads to a change of boundary conditions for all steady states having lesser characteristic time. It should not be very rapid. In the opposite case, the level of entropy production could change so much that the system achieves a critical unstable point of any included steady state. Passing through the critical point leads to reorganization of the entire hierarchy of the steady states or to the complete collapse of the system as a dissipative structure. Also one should take into account that living systems are the result of long-term biological evolution. The species that are able to maintain their integrity for the longest time interval have evolutionary advantage. Therefore, it is quite likely that difference between current value of the entropy production and value of the entropy production in nearest steady state is small enough to satisfy the laws of linear thermodynamics. Experimental data confirm the hypothesis. Limits of applicability of linear thermodynamics to biological systems are discussed. 展开更多
关键词 Entropy Production living systems LINEAR THERMODYNAMICS STEADY State
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Zero-Point Field, QED Coherence, Living Systems and Biophotons Emission
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作者 Luigi Maxmilian Caligiuri 《Open Journal of Biophysics》 2015年第1期21-34,共14页
Living organisms are high ordered and organized systems accumulating and successively using low entropy energy to support all the processes needed for life. This low level of entropy is a required condition in order t... Living organisms are high ordered and organized systems accumulating and successively using low entropy energy to support all the processes needed for life. This low level of entropy is a required condition in order to make possible the use of endogenous energy for producing, for example, mechanical work. The commonly accepted picture of condensed matter physics, exclusively considering the perturbative coupling between QED Zero-Point-Field also known as “Quantum Vacuum” and the matter system, is unable to thoroughly explain the true origin of this low entropy energy reservoir and its dynamics. Recent researches instead suggested that energy and mass of every particle or body could be actually considered as arising from Quantum Vacuum dynamics which, in turn, can exhibit, under suitable conditions always occurring in the case of living systems, a coherent behavior characterized by a strong phase correlation between matter and an electromagnetic field trapped inside this ensemble. In this paper the preliminary model of Quantum Vacuum already proposed by author is reformulated in terms of QED coherence in condensed matter showing it is able to explain the origin of internal energy stock of living organisms. Within this theoretical framework, an interpretation of some important experimental results about biophotons emission by living systems under the influence of external stimuli is also proposed, suggesting their origin could also arise from Quantum Vacuum dynamics. This model, as shown, opens very interesting and exciting scenarios of further developments in the understanding of the birth and dynamics of life. 展开更多
关键词 BIOENERGETICS Biophotons COHERENCE Energy and Mass Stock Entropy living ORGANISMS Non-Equilibrium systems QUANTUM ELECTRODYNAMICS QUANTUM Vacuum
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Effect of Hypomagnetic Field on Water Medium of Living Systems
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作者 Svetlana Stepanovna Moisa Vladimir Vladimirovich Tsetlin Elena Leonidovna Nefedova 《Journal of Biomedical Science and Engineering》 2019年第12期545-556,共12页
The article represents the generalizing data for the studying of the effect of hypomagnetic field on physico-chemistry properties of water and bio-objects. It was revealed the changing state of water: increasing of it... The article represents the generalizing data for the studying of the effect of hypomagnetic field on physico-chemistry properties of water and bio-objects. It was revealed the changing state of water: increasing of its oxidation-reduction potential and oxidative properties as magnetic induction attenuated pointing to a natural decline, that testifies about the regular decreasing of internal energy of water molecules, which, in our opinion, is caused the inhibition of the germination of seeds of the highest plants, embryonic development of Planorbarius corneus and the changing of energy state of growing mediums for cell culture of mammals. It is supposed that namely the changing state of water is the main component in the effects of weakening of magnetic field on the studying bio-objects. 展开更多
关键词 Hypomagnetic FIELD Water MEDIUM Oxidation-Reduction PROPERTIES living systems
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Living systems allometric scaling laws
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作者 Pierre Bricage 《Resources and Environmental Economics》 2019年第2期57-70,共14页
The spatial and temporal structuring and functioning of living systems are associated with scaling independent qualitative characteristics (gauge invariance) and quantitative laws (power laws). This is allowed by the ... The spatial and temporal structuring and functioning of living systems are associated with scaling independent qualitative characteristics (gauge invariance) and quantitative laws (power laws). This is allowed by the emergence of new blueprints through the systems merging into ‘Associations for the Reciprocal and Mutual Sharing of Advantages and Dis-Advantages’(ARMSADA). The local actors become more and more mutually integrated into their new global Whole. Then they are more and more independent from their previous local situations of emergence. Reversely (systemic constructal law), the global Whole is more and more integrating local parceners. The relationship between actors within a living system was described using allometric laws, e.g. the metabolic rate of a lot of species was supposed to be proportional to its mass according to a 3/4 exponent power-law (Kleiber’s law). But, according to the gauge invariance paradigm, an other explanation of the invariant scaling of living systems is proposed with a 2/3 power-law. Whatever its level of organization, a living system,‘system of systems’ emerging by embedments and juxtapositions of previous ones, effectively functions in 4 dimensions (VA: the Adult system Volume, and tg: the time of generation, the duration that is necessary to acquire the capacity of reproduction). Looking at the gauge invariance paradigm as a ‘factual’ system, from the quantum of Planck to the Universe as a Whole, a meta-analysis of a database of the systems internal (endophysiotope) and external (ecoexotope) interactions can allow to quantify 45-18 allometric relationships. This allows to evidence a ‘grammar’: 1. Invariant independent processes (power-laws with exponent e= 0);2. Simultaneous limiting interactions regulation processes (e=+1);3. Feedback (e=-1);4. Competition between actors (e= 1/2);5. Optimal exchanges flow (e= 2/3) processes. Brownian motion is the basic fundamental process that governs all functions. From the Monera to the ecosystem levels the increasing of regulation processes allows more and more autonomy of the endophysiotope from the ecoexotope dependence. From the point of view of matter and energy flows, living systems optimize the input and output exchanges at their interface. The greater diversity of regulation processes occurs for the endophysiotope throughput flows. Whatever the organization level, living systems optimize their survival by adjusting ‘the capacity to be hosted’ of their endophysiotope (HOSTED) to the changes of ‘the hosting capacity’ of their ecoexotope (HOSTING). 展开更多
关键词 living systems ALLOMETRIC scaling systemIC CONSTRUCTAL LAW POWER-LAWS Pieron’s LAW
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DS-MMAC:A Delay-Sensitive Multi-Channel MAC Protocol for Ambient Assistant Living Systems
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作者 Haiming Chen Li Cui 《China Communications》 SCIE CSCD 2016年第5期38-46,共9页
In Ambient Assistant Living(AAL) systems, it is a fundamental problem to ensure prompt delivery of detected events, such as irregular heart rate or fall of elderly, to a central processing device(e.g. gateway node). M... In Ambient Assistant Living(AAL) systems, it is a fundamental problem to ensure prompt delivery of detected events, such as irregular heart rate or fall of elderly, to a central processing device(e.g. gateway node). Most of recently proposed MAC protocols for low-power embedded sensing systems(e.g. wireless sensor networks) are designed with energy efficiency as the first goal, so they are not suitable for AAL systems. Although some multi-channel MAC protocols have been proposed to address the problem, most of those protocols ignore the cost of channel switching, which can have reverse effect on network performance, especially latency of data delivery. In this paper, we propose a Delay-Sensitive Multi-channel MAC protocol(DS-MMAC) for AAL systems, which can provide high packet delivery ratio and bound low latency for data delivered to the gateway node. The novelty of the protocol is that an efficient distributed time slot scheduling and channel assignment algorithm is combined with the process of route establishment, which takes the channel switching cost into account and reduces endto-end delay to meet the required delay bound of each data flow. The performance of the proposed protocol is evaluated through extensive simulations. Results show that DS-MMAC can bound low latency for delivering detected events in AAL system to the gateway, while providing high delivery reliability and low energy consumption. 展开更多
关键词 ambient assistant living multi-channel mac channel switching slot scheduling channel assignment
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Comparative study of living donor kidney transplants:Right vs left
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作者 Taqi Khan Nadeem Ahmad +4 位作者 Qaisar Iqbal Muneeb Hassan Lajward Asnath Naveed Khan Sajid Shakeel 《World Journal of Transplantation》 2025年第1期115-123,共9页
BACKGROUND Transplant teams often hesitate to use the right kidney(RK)in living donor(LD)transplants due to the complexities of anastomosing the short,thin-walled right renal veins,which can potentially lead to graft ... BACKGROUND Transplant teams often hesitate to use the right kidney(RK)in living donor(LD)transplants due to the complexities of anastomosing the short,thin-walled right renal veins,which can potentially lead to graft loss or graft dysfunction.Nevertheless,circumstances may arise where selecting the RK over the left kidney(LK)is unavoidable.Consequently,it is crucial to thoroughly examine the implications of such a choice on the overall transplant outcome.AIM To compare transplant outcomes between recipients of RK and LK while examining the factors that influence these outcomes.METHODS We retrospectively analyzed data from adult patients who received LD kidney transplants involving meticulous patient selection and surgical techniques at our center from January 2020 to December 2023.We included all kidney donors who were over 18,fit to donate,and had undergone diethylenetriamine pentaacetic acid split function and/or computed tomography based volumetry.The variables examined comprised donor and recipient demographics,and outcome measures included technical graft loss(TGL),delayed or slow graft function(SGF),and post-transplant serum creatinine(SC)trends.We used a logistic regression model to assess the likelihood of adverse outcomes considering the donor kidney side.RESULTS Of the 250 transplants performed during the period,56(22%)were RKs.The recipient demographics and transplant factors were comparable for the right and LKs,except that the donor warm and cold ischemia time were shorter for RKs.TGL and SGF each occurred in 2%(n=1)of RKs and 0.5%(n=1)of LKs,the difference being insignificant.These complications,however,were not related to the venous anastomosis.One RK(2%)developed delayed graft function after 48 hours,which was attributable to postoperative hypoxia rather than the surgical technique.The post-transplant SC trend and mean SC at the last follow-up were similar across both kidney sides.CONCLUSION The donor kidney side has little impact on post-transplant adverse events and graft function in LD transplants,provided that careful patient selection and precise surgical techniques are employed. 展开更多
关键词 living donor Right kidney Right renal vein Venous anastomosis Technical graft loss Early graft function
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Structure for energy cycle: a unique status of the second law of thermodynamics for living systems 被引量:1
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作者 Shunong Bai Hao Ge Hong Qian 《Science China(Life Sciences)》 SCIE CAS CSCD 2018年第10期1266-1273,共8页
Distinguishing things from beings, or matters from lives, is a fundamental question. Extending E. Schr?dinger's neg-entropy and I. Prigogine's dissipative structure, we propose a chemical kinetic view that the... Distinguishing things from beings, or matters from lives, is a fundamental question. Extending E. Schr?dinger's neg-entropy and I. Prigogine's dissipative structure, we propose a chemical kinetic view that the earliest "live" process is embedded essentially in a special interaction between a pair of specific components under a particular, corresponding environmental conditions. The interaction exists as an inter-molecular-force-bond complex(IMFBC) that couples two separate chemical processes: one is the spontaneous formation of the IMFBC driven by a decrease of Gibbs free energy as a dissipative process; while the other is the disassembly of the IMFBC driven thermodynamically by free energy input from the environment. The two chemical processes coupled by the IMFBC originated independently and were considered non-living on Earth, but the IMFBC coupling of the two can be considered as the earliest form of metabolism: the first landmark on the path from things to a being. The dynamic formation and disassembly of the IMFBC, as a composite individual, follows a principle designated as "… structure for energy for structure for energy…", the cycle continues; and for short it will be referred to as "structure for energy cycle". With additional features derived from this starting point, the IMFBC-centered "live" process spontaneously evolved into more complex living organisms with the characteristics currently known. 展开更多
关键词 structure energy living systems IMFBC CYCLE
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A highly specific ratiometric two-photon fluorescent probe to detect dipeptidyl peptidase Ⅳ in plasma and living systems 被引量:2
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《Science Foundation in China》 CAS 2017年第1期39-,共1页
Subject Code:H30With the support by the National Natural Science Foundation of China and National Basic Research Program of China,the group led by Prof.Ge Guangbo(葛广波)and Prof.Yang Ling(杨凌)from the Laboratory of ... Subject Code:H30With the support by the National Natural Science Foundation of China and National Basic Research Program of China,the group led by Prof.Ge Guangbo(葛广波)and Prof.Yang Ling(杨凌)from the Laboratory of Pharmaceutical Resource Discovery,Dalian Institute of Chemical Physics,Chinese Academy of Sciences,reported a highly specific ratiometric two-photon fluorescent probe to detect 展开更多
关键词 DPP in plasma and living systems A highly specific ratiometric two-photon fluorescent probe to detect dipeptidyl peptidase IV
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NMR Dynamic Studies in Living Systems
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作者 闫永彬 范明杰 +1 位作者 罗雪春 张日清 《Tsinghua Science and Technology》 SCIE EI CAS 2002年第4期340-346,共7页
Nuclear magnetic resonance (NMR) can noninvasively monitor the intracellular concentrations and kinetic properties of numerous inorganic and organic compounds. These characteristics have made NMR a useful tool for ... Nuclear magnetic resonance (NMR) can noninvasively monitor the intracellular concentrations and kinetic properties of numerous inorganic and organic compounds. These characteristics have made NMR a useful tool for dynamic studies of living systems. Applications of NMR to living systems have successfully extended to many areas, including studies of metabolic regulation, ion transport, and intracellular reaction rates in vivo. The major purpose of this review is to summarize the results that can be obtained by modern NMR techniques in living systems. With the advances of new techniques, NMR measurements of various nuclides have been performed for specific physiological purposes. Although some technical problems still remain and there are still discrepancies between NMR and traditional biochemical results, the abundant and unique information obtained from NMR spectra suggests that NMR will be more extensively applied in future studies of living systems. The fast development of these new techniques is providing many new NMR applications in living systems, as well as in structural biology. 展开更多
关键词 nuclear magnetic resonance (NMR) living systems dynamic studies
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Proximity Chemistry in Living Systems
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作者 Yanjun Liu Yun Ge +3 位作者 Ruxin Zeng William Shu Ching Ngai Xinyuan Fan Peng R.Chen 《CCS Chemistry》 CSCD 2023年第4期802-813,共12页
Enzyme-and catalyst-generated reactive species have been leveraged in the past decade to covalently label biomolecules within a short range of a defined site or space inside cells or at the cell–cell interface.Due to... Enzyme-and catalyst-generated reactive species have been leveraged in the past decade to covalently label biomolecules within a short range of a defined site or space inside cells or at the cell–cell interface.Due to their high spatial resolution,such proximity labeling strategies have been coupled with various bioanalytical techniques for dissecting dynamic and complex biological processes.Here,we review the development of enzyme-and catalyst-triggered proximity chemistry and their applications to identifying protein interaction networks as well as cell–cell communications in living systems. 展开更多
关键词 proximity labeling bioorthogonal chemistry spatiotemporal proteomics cell-cell interactions living systems
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Restoring nervous system structure and function using tissue engineered living scaffolds 被引量:5
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作者 Laura A.Struzyna James P.Harris +2 位作者 Kritika S.Katiyar H.Isaac Chen D.Kacy Cullen 《Neural Regeneration Research》 SCIE CAS CSCD 2015年第5期679-685,共7页
Neural tissue engineering is premised on the integration of engineered living tissue with the host nervous system to directly restore lost function or to augment regenerative capacity following ner- vous system injury... Neural tissue engineering is premised on the integration of engineered living tissue with the host nervous system to directly restore lost function or to augment regenerative capacity following ner- vous system injury or neurodegenerative disease. Disconnection of axon pathways - the long-distance fibers connecting specialized regions of the central nervous system or relaying peripheral signals - is a common feature of many neurological disorders and injury. However, functional axonal regenera- tion rarely occurs due to extreme distances to targets, absence of directed guidance, and the presence of inhibitory factors in the central nervous system, resulting in devastating effects on cognitive and sensorimotor function. To address this need, we are pursuing multiple strategies using tissue engi- neered "living scaffolds", which are preformed three-dimensional constructs consisting of living neural cells in a defined, often anisotropic architecture. Living scaffolds are designed to restore function by serving as a living labeled pathway for targeted axonal regeneration - mimicking key developmental mechanisms- or by restoring lost neural circuitry via direct replacement of neurons and axonal tracts. We are currently utilizing preformed living scaffolds consisting of neuronal dusters spanned by long axonal tracts as regenerative bridges to facilitate long-distance axonal regeneration and for targeted neurosurgical reconstruction of local circuits in the brain. Although there are formidable challenges in predinical and clinical advancement, these living tissue engineered constructs represent a promising strategy to facilitate nervous system repair and functional recovery. 展开更多
关键词 living scaffolds neural tissue engineering cell transplant BIOMATERIALS regeneration NEUROTRAUMA NEURODEGENERATION axon pathfinding cell migration
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Different techniques for harvesting grafts for living donor liver transplantation: A systematic review and meta-analysis 被引量:6
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作者 Hui Li Jun-Bin Zhang +8 位作者 Xiao-Long Chen Lei Fan Li Wang Shi-Hui Li Qiao-Lan Zheng Xiao-Ming Wang Yang Yang Gui-Hua Chen Gen-Shu Wang 《World Journal of Gastroenterology》 SCIE CAS 2017年第20期3730-3743,共14页
AIM To perform a systematic review and meta-analysis on minimally vs conventional invasive techniques for harvesting grafts for living donor liver transplantation. METHODS PubMed, Web of Science, EMBASE, and the Cochr... AIM To perform a systematic review and meta-analysis on minimally vs conventional invasive techniques for harvesting grafts for living donor liver transplantation. METHODS PubMed, Web of Science, EMBASE, and the Cochrane Library were searched comprehensively for studies comparing MILDH with conventional living donor hepatectomy (CLDH). Intraoperative and postoperative outcomes (operative time, estimated blood loss, postoperative liver function, length of hospital stay, analgesia use, complications, and survival rate) were analyzed in donors and recipients. Articles were included if they: (1) compared the outcomes of MILDH and CLDH; and (2) reported at least some of the above outcomes. RESULTS Of 937 articles identified, 13, containing 1592 patients, met our inclusion criteria and were included in the meta-analysis. For donors, operative time [weighted mean difference (WMD) = 20.68, 95% CI: -6.25-47.60, p = 0.13] and blood loss (WMD = -32.61, 95% CI: -80.44-5.21, p = 0.18) were comparable in the two groups. In contrast, analgesia use (WMD = -7.79, 95% CI: -14.06-1.87, p = 0.01), postoperative complications [odds ratio (OR) = 0.62, 95% CI: 0.44-0.89, p = 0.009], and length of hospital stay (WMD): -1.25, 95% CI: -2.35-0.14, p = 0.03) significantly favored MILDH. No differences were observed in recipient outcomes, including postoperative complications (OR = 0.93, 95% CI: 0.66-1.31, p = 0.68) and survival rate (hr = 0.96, 95% CI: 0.27-3.47, p = 0.95). Funnel plot and statistical methods showed a low probability of publication bias. CONCLUSION MILDH is safe, effective, and feasible for living donor liver resection with fewer donor postoperative complications, reduced length of hospital stay and analgesia requirement than CLDH. 展开更多
关键词 living donor hepatectomy Graft harvesting Minimally invasive techniques Conventional invasive approaches META-ANALYSIS
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Weight loss interventions in living donor liver transplantation as a tool in expanding the donor pool: A systematic review and metaanalysis 被引量:5
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作者 Sushrut Trakroo Nakul Bhardwaj +1 位作者 Rajat Garg Jamak Modaresi Esfeh 《World Journal of Gastroenterology》 SCIE CAS 2021年第24期3682-3692,共11页
BACKGROUND With increasing rates of liver transplantation and a stagnant donor pool,the annual wait list removals have remained high.Living donor liver transplantation(LDLT)is an established modality in expanding the ... BACKGROUND With increasing rates of liver transplantation and a stagnant donor pool,the annual wait list removals have remained high.Living donor liver transplantation(LDLT)is an established modality in expanding the donor pool and is the primary method of liver donation in large parts of the world.Marginal living donors,including those with hepatic steatosis,have been used to expand the donor pool.However,due to negative effects of steatosis on graft and recipient outcomes,current practice excludes overweight or obese donors with more than 10%macro vesicular steatosis.This has limited a potentially important source to help expand the donor pool.Weight loss is known to improve or resolve steatosis and rapid weight loss with short-term interventions have been used to convert marginal donors to low-risk donors in a small series of studies.There is,however,a lack of a consensus driven standardized approach to such interventions.AIM To assess the available data on using weight loss interventions in potential living liver donors with steatotic livers and investigated the feasibility,efficacy,and safety of using such donors on the donor,graft and recipient outcomes.The principal objective was to assess if using such treated donor livers,could help expand the donor pool.METHODS We performed a comprehensive literature review and meta-analysis on studies examining the role of short-term weight loss interventions in potential living liver donors with hepatic steatosis with the aim of increasing liver donation rates and improving donor,graft,and recipient outcomes.RESULTS A total of 6 studies with 102 potential donors were included.Most subjects were males(71).All studies showed a significant reduction in body mass index postintervention with a mean difference of-2.08(-3.06,1.10,I2=78%).A significant reduction or resolution of hepatic steatosis was seen in 93 of the 102(91.2%).Comparison of pre-and post-intervention liver biopsies showed a significant reduction in steatosis with a mean difference of-21.22(-27.02,-15.43,I2=56%).The liver donation rates post-intervention was 88.5(74.5,95.3,I2=42%).All donors who did not undergo LDLT had either recipient reasons or had fibrosis/steatohepatitis on post intervention biopsies.Post-operative biliary complications in the intervention group were not significantly different compared to controls with an odds ratio of 0.96[(0.14,6.69),I2=0].The overall post-operative donor,graft,and recipient outcomes in treated donors were not significantly different compared to donors with no steatosis.CONCLUSION Use of appropriate short term weight loss interventions in living liver donors is an effective tool in turning marginal donors to low-risk donors and therefore in expanding the donor pool.It is feasible and safe,with comparable donor,graft,and recipient outcomes,to non-obese donors.Larger future prospective studies are needed. 展开更多
关键词 living donor liver transplant living liver donors Liver steatosis Weight loss interventions Donor outcomes Recipient outcomes
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Sensing carboxylesterase 1 in living systems by a practical and isoformspecific fluorescent probe 被引量:2
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作者 Lele Ding Zhenhao Tian +8 位作者 Jie Hou Tongyi Dou Qiang Jin Dandan Wang Liwei Zou Yadi Zhu Yunqing Song Jingnan Cui Guangbo Ge 《Chinese Chemical Letters》 SCIE CAS CSCD 2019年第3期558-562,共5页
Carboxylesterase 1(CES1), one of the most abundant serine hydrolases in mammals, has drawn much attentions in recent years, owing to this enzyme involves in many physiological processes via hydrolysis of both endogeno... Carboxylesterase 1(CES1), one of the most abundant serine hydrolases in mammals, has drawn much attentions in recent years, owing to this enzyme involves in many physiological processes via hydrolysis of both endogenous esters and xenobiotic esters. Herein, to real-time monitor the activities of CES1 in various biological systems, a practical and iso form-specific fluorescent probe was developed on the basis of the substrate preference of CES1, as well as the structural and optical properties of BODIPY dyes. After screening of a panel of BODIPY ester derivatives, probe 1 displayed the best combination of specificity,sensitivity, enzymatic kinetics and applicability for monitoring CES1 activities in real samples. This probe was successfully used to detect CESl activities in several biological systems including tissue preparations,living cells, tissue slices and zebrafish. Furthermore, the biomedical applications of probe 1 for screening of CES1 inhibitors were also demonstrated using tissue preparations or living cells as enzyme sources. In summary, a practical and broadly applicable tool for real-time monitoring CES1 in biological systems was developed and well-characterized, which held great promise for further investigations on CES1-associated drug discovery, clinical practice and fundamental research. 展开更多
关键词 CARBOXYLESTERASE 1 FLUORESCENT probe Biological imaging living cells based INHIBITORS screening BODIPY DYES
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