Mathematical model describing erythrocyte sedimentation rate. Implications for blood viscosity changes in traumatic shock and crush syndrome

BACKGROUND: The erythrocyte sedimentation rate (ESR) is a simple and inexpensive laboratory test, which is widespread in clinical practice, for assessing the inflammatory or acute response. This work addresses the theoretical and experimental investigation of sedimentation a single and multiple particles in homogeneous and heterogeneous (multiphase) medium, as it relates to their internal structure (aggregation of solid or deformed particles). METHODS: The equation system has been solved numerically. To choose finite analogs of derivatives we used the schemes of directional differences. RESULTS: (1) Our model takes into account the influence of the vessel wall on group aggregation of particles in tubes as well as the effects of rotation of particles, the constraint coefficient, and viscosity of a mixture as a function of the volume fraction. (2) This model can describe ESR as a function of the velocity of adhesion of erythrocytes; (3) Determination of the ESR is best conducted at certain time intervals, i.e. in a series of periods not exceeding 5 minutes each; (4) Differential diagnosis of various diseases by means of ESR should be performed using the aforementioned timed measurement of ESR; (5) An increase in blood viscosity during trauma results from an increase in rouleaux formation and the time-course method of ESR will be useful in patients with trauma, in particular, with traumatic shock and crush syndrome. CONCLUSION: The mathematical model created in this study used the most fundamental differential equations that have ever been derived to estimate ESR. It may further our understanding of its complex mechanism

Heterosynaptic plasticity in the neocortex

Ongoing learning continuously shapes the distribution of neurons’ synaptic weights in a system with plastic synapses. Plasticity may change the weights of synapses that were active during the induction—homosynaptic changes, but also may change synapses not active during the induction—heterosynaptic changes. Here we will argue, that heterosynaptic and homosynaptic plasticity are complementary processes, and that heterosynaptic plasticity might accompany homosynaptic plasticity induced by typical pairing protocols. Synapses are not uniform in their susceptibility for plastic changes, but have predispositions to undergo potentiation or depression, or not to change. Predisposition is one of the factors determining the direction and magnitude of homo- and heterosynaptic changes. Heterosynaptic changes which take place according to predispositions for plasticity may provide a useful mechanism(s) for homeostasis of neurons’ synaptic weights and extending the lifetime of memory traces during ongoing learning in neuronal networks

Global epidemics of childhood obesity is hitting a 'less industrialized' corner in Asia: A case study in Macao

Childhood obesity prevalence amongst children is rising virtually in all countries with rapid acceleration in major cities in China. A cross-sectional study was conducted amongst 2,015 primary and secondary students in Macao to investigate the nutritional status and analyzed for the relationship of overweight and other cardio-metabolic risk factors. Subjects were randomly selected in proportion to the gender and age of the population. A total of 26.4% of boys and 13.9% of girls were overweight or obese with the highest prevalence around 40% among boys aged 9-12 and girls aged 10 and 11. Some 18.1% of boys and 20.4% of girls were found to have borderline LDL levels; a further 9.3% and 10.4% were found to have high-risk, respectively. For those students with overweight and obesity, a significant higher proportion of them had cardio-metabolic risk factors. Based on this evidence, there is a concern that obesity and its associated co-morbidity could reach epidemic proportions in the 'less industrialized' cities of China. © 2011 Informa Healthcare.Link_to_subscribed_fulltex