Lecarpentier Yves, Claes Victor, Hébert Jean-Louis, Krokidis Xénophon, Blanc François-Xavier, Michel Francine, Timbely Oumar
Centre de Recherche Clinique, Centre Hospitalier Régional de Meaux, Meaux, France.
Department of Pharmaceutical Sciences, University of Antwerp, Wilrijk, Belgium.
PLoS One. 2015 Nov 16;10(11):e0142471. doi: 10.1371/journal.pone.0142471. eCollection 2015.
All near-equilibrium systems under linear regime evolve to stationary states in which there is constant entropy production rate. In an open chemical system that exchanges matter and energy with the exterior, we can identify both the energy and entropy flows associated with the exchange of matter and energy. This can be achieved by applying statistical mechanics (SM), which links the microscopic properties of a system to its bulk properties. In the case of contractile tissues such as human placenta, Huxley's equations offer a phenomenological formalism for applying SM. SM was investigated in human placental stem villi (PSV) (n = 40). PSV were stimulated by means of KCl exposure (n = 20) and tetanic electrical stimulation (n = 20). This made it possible to determine statistical entropy (S), internal energy (E), affinity (A), thermodynamic force (A / T) (T: temperature), thermodynamic flow (v) and entropy production rate (A / T x v). We found that PSV operated near equilibrium, i.e., A ≺≺ 2500 J/mol and in a stationary linear regime, i.e., (A / T) varied linearly with v. As v was dramatically low, entropy production rate which quantified irreversibility of chemical processes appeared to be the lowest ever observed in any contractile system.
所有处于线性区域的近平衡系统都会演化为具有恒定熵产生率的稳态。在一个与外部进行物质和能量交换的开放化学系统中，我们可以确定与物质和能量交换相关的能量流和熵流。这可以通过应用统计力学（SM）来实现，统计力学将系统的微观性质与其宏观性质联系起来。对于诸如人胎盘等收缩组织，赫胥黎方程提供了一种应用统计力学的唯象形式。对人胎盘干细胞绒毛（PSV）（n = 40）进行了统计力学研究。通过氯化钾暴露（n = 20）和强直电刺激（n = 20）对PSV进行刺激。这使得确定统计熵（S）、内能（E）、亲和势（A）、热力学力（A/T）（T：温度）、热力学流（v）和熵产生率（A/T×v）成为可能。我们发现PSV在近平衡状态下运行，即A≪2500 J/mol，并且处于稳态线性区域，即（A/T）与v呈线性变化。由于v极低，量化化学过程不可逆性的熵产生率似乎是在任何收缩系统中观察到的最低值。
