Although Yin-Yang Wu-Xing (Yin-Yang and Five-Elements, subsystems of human body) has been the theoretical basis of traditional Chinese medicine (TCM) for more than 5 000 years, it has been primarily analytical or empirical in nature without a formal scientific foundation. Based on bipolar set theory, an equilibrium/non-equilibrium computational model of Yin-Yang Wu-Xing is proposed. The Yin-Yang Wu-Xing dynamical systems are formulated so that equilibrium and non-equilibrium conditions can be established and proved. Computer simulations of equilibrium and non-equilibrium processes show that this new approach can provide diagnostic decision support in TCM. Thus, this equilibrium-based approach provides a unique scientific basis for future research in TCM, Qi (vital energy), QiGong, Meridians and Collaterals (acupuncture channels) and herbal treatment. On the other hand, it provides a basic Yin-Yang cellular network architecture for modem scientific research in genomics such that regulation mechanisms of the ubiquitous YY1 protein for cell processes can be explained.

Hypoxia inducible factor-1αis a kind of hypoxia response factor. Acute cerebral ischemia and anoxia can induce up-regula-tion of hypoxia inducible factor-1α, and the downstream genes, which plays a role in both the energy metabolism and collateral circulation after cerebral ischemia. Neural stem and progenitor cells regeneration also benefit the functional outcome after ischemic stroke. Hypoxia in-ducible factor-1αmay induce proliferation and differentiation of neural stem and progenitor cells through Notch, Wnt/β-catenin pathways, etc., in the ischemic stroke model.

Objective To evaluate cerebral perfusion through brain computed tomography perfusion imaging (CTP) in order to investigate the relationship between cerebral perfusion and vascular cognitive impairment (VCI).Methods A total of 103 patients with ischemic stroke were recruited, who received thrombolytic therapy and CTP test in the Fourth Affiliated Hospital of China Medical University from December, 2016 to May, 2017. The patients were divided into normal cognitive function group (control group, n=43), vascular cognitive impairment-no dementia group (VCIND group, n=48), and vascular dementia group (VD group, n=12) according to the degree of impairment in cognitive function after the assessment of Mini-Mental State Examination (MMSE) and Clock Drawing Test (CDT). The characteristics of cerebral blood flow perfusion in region of interest of brain CTP were analyzed.Results There was difference in incidence of diabetes among three groups (χ2=7.556, P<0.05). The rate of diabetes was higher in VCIND group and VD group than in the control group. Age and diabetes were the independent risk factors for VCI (OR>1, P<0.05). There was difference in cerebral blood volume (CBV) in frontal lobe, temporal lobe, and parietal lobe among three groups (F>3.216, P<0.05). CBV in frontal lobe, temporal lobe, and parietal lobe reduced in VD group than in the control group (P<0.05), while CBV in frontal lobe and temporal lobe reduced in VD group than in VCIND group (P<0.05). There was difference in mean transit time (MTT) in left temporal lobe, left parietal lobe, and centrum semiovale among three groups, while there was difference in left occipital lobe in time to peak (TTP) among three groups (F>3.116, P<0.05). MTT and TTP were higher in VD group than in the control group and VCIND group (P<0.05). There was no difference in cerebral blood flow (CBF) in both left and right brain, and MTT and TTP in right brain among three groups (P>0.05). CBV in frontal lobe, parietal lobe and right temporal lobe demonstrated positive relationship with the scores of MMSE (r>0.203, P<0.05). CBV in parietal lobe and left frontal lobe also demonstrated positive relationship with the scores of CDT (r>0.214, P<0.05).Conclusion The cerebral blood flow perfusion reduced in different levels of VCI, especially in frontal lobe, temporal lobe and parietal lobe. Cerebral blood flow perfusion reduced with the progress of cognitive impairment, and the left hemisphere injured earlier than the right one. Brain CTP may be applied in the early recognition of VCI.