Correlation between special brain area and blood perfusion in patients with cerebral infarction at convalescent period Feasibility for quantitative determination and estimation of learning and memory function

BACKGROUND： Presently, clinic memory scale is used to evaluate learning memory ability in most studies, and the influence of difference in measurement condition of individuals exists. OBJECTIVE： To study the correlation between regional cerebral blood flow （rCBF） perfusion and learning memory function in special brain regions of patients with cerebral infarction at convalescent period, and to try to find out a method which can quantitatively evaluate learning ability. DESIGN： Case observation, and correlation analysis. SETTINGS： Shandong Institute for Behavioral Medicine; the Affiliated Hospital of Jining Medical College. PARTICIPANTS： Totally 70 patients with cerebral infarction admitted to Department of Neurology, Jining Medical College between January 2004 and December 2005 were involved. The involved patients, 58 male and 12 female, were averaged （52±3） years, and they were all right handed. They all met the diagnosis criteria instituted by the Fourth National Conference on Cerebrovascular Disease, and were confirmed as cerebral infarction by skull CT or MRI. Informed consents of detected items were obtained from all the patients and relatives. METHODS： When the patients were at convalescent period, their learning and memory ability were measured with “ clinic memory scale （set A）”. The 18 patients whose total mark over 100 were regarded as good learning memory function group; The 23 cases whose total mark less than 70 were regarded as poor learning memory function group. RCBF of hippocampus, nucleus amygdalae, temporal cortex and prefrontal lobe of patients between two groups were measured and compared by single photon emission computed tomography （SPECT）. The total scores of the 18 good learning memory patients and 23 poor learning memory patients were taken as dependent variable Y, and their rCBFs of hippocampus, nucleus amygdale, temporal cortex and prefrontal lobe respectively as independent variable X for linear correlation analysis. MAIN OUTCOME MEASURES： Correlation of rCBF in different brain regions and learning memory ability in patients with cerebral infarction. RESULTS： ①The rCBF of hippocampus, nucleus amygdale, temportal cortex and prefrontal cortex of good learning memory function group were significantly higher than those of poor learning memory function group （P 〈 0.05）. ②In the good learning memory function group, rCBF of hippocampus, nucleus amygdale, temportal cortex and prefrontal cortex were significantly positively correlated with memory scale scores （ r = 0.961, 0.926, 0.954, 0.907, P 〈 0.05 ） , and also in the poor learning memory function group （r = 0.979, 0.976, 0.991, 0.953, P 〈 0.05 ） . CONCLUSION： The rCBF of hippocampus, nucleus amygdale, temportal cortex and prefrontal cortex of patients with cerebral infarction are significantly positively correlated with memory scale scores. Predicting learning memory ability of patients by quantitative determination of rCBF provides a quantitative and objective method for evaluating learning memory ability.

circBIRC6 contributes to the development of non-small cell lung cancer via regulating microRNA-217/amyloid beta precursor protein binding protein 2 axis

Background:Circular RNAs(circRNAs)are considered to be important regulators in cancer biology.In this study,we focused on the effect of circRNA baculoviral inhibitor of apoptosis protein(IAP)repeat containing 6(circBIRC6)on non-small cell lung cancer(NSCLC)progression.Methods:The NSCLC and adjacent non-tumor tissues were collected at Shanghai Ninth People's Hospital.Quantitative real-time polymerase chain reaction was conducted for assessing the levels of circBIRC6,amyloid beta precursor protein binding protein 2(APPBP2)messenger RNA(mRNA),baculoviral IAP repeat containing 6 mRNA(BIRC6),and microRNA-217(miR-217).Western blot assay was adopted for measuring the protein levels of APPBP2,E-cadherin,N-cadherin,and vimentin.Colony formation assay,transwell assay,and flow cytometry analysis were utilized for evaluating cell colony formation,metastasis,and apoptosis.Dualluciferase reporter assay and RNA immunoprecipitation assay were carried out to determine the interaction between miR-217 and circBIRC6 and APPBP2 in NSCLC tissues.The murine xenograft model assay was used to investigate the function of circBIRC6 in tumor formation in vivo.Differences were analyzed via Student's t test or one-way analysis of variance.Pearson's correlation coefficient analysis was used to analyze linear correlation.Results:CircBIRC6 was overexpressed in NSCLC tissues and cells.Knockdown of circBIRC6 repressed the colony formation and metastasis and facilitated apoptosis of NSCLC cells in vitro and restrained tumorigenesis in vivo.Mechanically,circBIRC6 functioned as miR-217 sponge to promote APPBP2 expression in NSCLC cells.MiR-217 inhibition rescued circBIRC6 knockdown-mediated effects on NSCLC cell colony formation,metastasis,and apoptosis.Overexpression of miR-217 inhibited the malignant phenotypes of NSCLC cells,while the effects were abrogated by elevating APPBP2.Conclusion:CircBIRC6 aggravated NSCLC cell progression by elevating APPBP2 via sponging miR-217,which might provide a fresh perspective on NSCLC therapy.

Secondary instability of separated shear layers

The process through which a laminar flow undergoes transition to turbulence is of great fundamental and practical interest. Such a process is hugely complex as there are many diverse routes for a laminar flow to become turbulent flow. The transition process is usually initiated by flow instabilities—a primary instability stage followed by a secondary instability stage. This forms a rational framework for the early stage of a transition process and it is crucially important to understand the physics of instabilities leading to turbulence. This article reviews the results of studies on secondary instability of separated shear layers in separation bubbles and summaries the current status of our understanding in this area.

Effects of special brain area regional cerebral blood flow abnormal perfusion on learning and memory function and its molecular mechanism in rats

To study the effect of special brain area regional cerebral blood flow(rCBF)abnormal perfusion on learning and memory function and its molecular mechanism,64 adult male healthy Sprague-Dawley(SD)rats were randomly divided into two groups,the false operation group(control group)and the operation group(model group).After surgical operation,the operation group undertook bilateral common carotid artery permanent ligation,while the other group did not.Learning and memory function were measured by Y-maze at 4 h,8 h,24 h and 3 d after surgical operation,respectively.The rCBF of the right frontal lobe and hippocampus was also detected by the PerifluxPF model laser Doppler flowmetry,and the expressions of c-fos or c-jun or Bcl-2 and Bax were also measured by immune histochemistry S-P method accordingly.Results showed that the rCBF of the right frontal lobe and hippocampus in the operation group was significantly lower than that in the false operation group(P,0.05).The learning indexes,error number(EN),day of reach standard and total reaction time(TRT)in the operation group,were significantly higher than that in the false operation group(P,0.05).However,the initiative evasion rate in the operation group was significantly lower than that in the false operation group.The study also found that the rCBF was relatively more,the indexes(EN,the day of reach standard and TRT)relatively fewer,but the initiative evasion rate and the memory keeping rate were relatively more.The positive expression and the average absorbency of Fos and Jun in the operation group were significantly higher than that in the false operation group(P<0.05).Furthermore,Bax and Bcl-2 positive cells were all increased over time in the operation group,and the expression ratio of Bax/Bcl-2 in the operation group was significantly higher than that in the false operation group(P<0.01).In conclusion,rCBF decrease can impair the learning and memory function in rats,which may be related to the increase of the expression ratio of c-fos or c-jun or Bcl-2 or Bax in the frontal cortex and hippocampus.

On bypass transition in separation bubbles:a review

Transition from laminar flow to turbulent flow is of great practical interest as it occurs in many engineering flows and often plays a critical role in aerodynamics and heat transfer performance of those flow devices.There could be many routes through transition,depending on flow configuration,geometry and the way in which transition is initiated by a wide range of possible background disturbances such as free-stream turbulence,pressure gradient,acoustic noise,wall roughness and obstructions,periodic unsteady disturbance and so on.This paper presents a brief overview of wall bounded flow transition in general and focuses more on the transition process in the free shear layer of separation bubbles,demonstrating that at elevated free-stream turbulent intensity the so called bypass transition could occur in geometrically induced separation bubbles where the separation point is fixed.