The study of brain information flow is of great significance to understand brain function in the field of neuroscience. The Granger causality is widely used functional connectivity analysis using multivariate autoregressive model based on the predicted mechanism. High resolution electroencephalogram (EEG) signals of ten healthy subjects were collected with a visual selective attention task. Firstly, independent component analysis was used to extract three spatially independent components of the occipital, parietal, and frontal cortices. Secondly, the Granger causal connectivity was computed between these three regions based on the Granger causality method and then independent sample t-test and bootstrap were used to test the significance of connections. The results showed that Granger causal connectivity existed from frontal to occipital and from parietal to occipital in attentional condition, while causal connectivity from frontal to occipital disappeared in unattentional condition.
Algorithms ; Attention ; Brain ; physiology ; Electroencephalography ; Healthy Volunteers ; Humans

Hypoxia is very common in solid tumor.It results in a series of changes of biological behavior in tumor cells.Hypoxia could facilitate malignant cells metastasis,in which the hypoxia inducible factor-1 plays an important role.The hypothesis for the tumor cells to metastasis is the degradation of the extracellular matrix(ECM).The ECM can be degraded by the matrix metalloproteinase,which is a critical factor in the process of tumor-metastasis.So far,it is not clear whether hypoxia have a role in the regulation of MMPs in tumor.So this review summarize the advanced knowledge on the influence of HIF-1 and MMPs in tumor-metastasis and the interaction between two genes.

[Objective]To evaluate the outcome of the Pemberton osteotomy for the treatment of developmental dysplasia of the hip (DDH) in older children. [Method]There were 21 children (24 hips) older than 7 years in our study , who received the Pemberton osteotomy, and combined with femoral shortening, derotational or varus osteotomies according to the level of dislocation, anteversion and neck-shalf angle of the femur. The average age at operation were 9 years and 7 months (range: 7~13.5 years).[Result]The mean follow-up were 5 years and 5 months. Eighteen hips achieved the excellent or good clinical results according to the McKay's clinical criteria. All of the hips got improvements of the Acetabular Index, Sharp Acetabular Angle, Center-Edge Angle and Acetabular Head Index. The average results were in the normal range. Eighteen hips got ⅠorⅡclass of the Severin’s radiographic classification.However, 9 hips were limited in the range of movement. Four hips got subluxation.Six hips developed avascular necrosis of the femoral head. Three hips got improved osteoarthritis.[Conclusion]The Pemberton osteotomy for the treatment of developmental dysplasia of the hip in older children can mostly achieve well-used, contained or concentric reduction hips, meanwhile need to reduce the complications.

Objective:To investigate and compare the influences of Ghrelin and growth hormone releasing peptide 6(GHRP-6) on the contractility of stomach smooth muscle in guinea pigs,and to study the related mechanism.Methods: The myenteric plexuses of gastric fundus and antrium in guinea pigs were stimulated with electrical field stimulation(EFS) to observe the influence of Ghrelin and GHRP-6 on the contractility of stomach smooth muscle.The influences of N-nitro-L-arginine(L-NNA) and L-Arginine(L-AA) on the effect of Ghrelin and GHRP-6 were studied to disclose the mechanism of the effects of Ghrelin and GHRP-6.Results: The circular muscle tissues of the gastric fundus generated on-relaxations and off-contractions when stimulating myenteric plexuses with 1-16 Hz electrical field;the on-responses induced relaxation could be reduced by L-NNA and the off-contractions induced contraction could be blocked by atropine and guanethidine.In fundic strips,ghrelin and GHRP-6 could decrease the on-response induced relaxation and increase off-response induced contraction of the muscle,with the effect of Ghrelin obviously stronger than that of GHRP-6.L-NNA could increase the effects of Ghrelin and GHRP-6-induced muscle contraction,and L-AA could decrease their effects.In the antral strips,electrical field stimulation of myenteric plexuses led to disappearance of relaxation wave,only leaving off-contractions.Both ghrelin and GHRP-6 could increase that contraction.Conclusion: Both ghrelin and GHRP-6 can promote the contractility of stomach smooth muscle in guinea pigs through stimulating myenteric plexuses of gastric fundus and antrium,which might be related to the NO pathway.

Objective: To investigate and compare the influences of Ghrelin and growth hormone releasing peptide 6 (GHRP-6) on the contractility of stomach smooth muscle in guinea pigs, and to study the related mechanism. Methods: The myenteric plexuses of gastric fundus and antrium in guinea pigs were stimulated with electrical field stimulation (EFS) to observe the influence of Ghrelin and GHRP-6 on the contractility of stomach smooth muscle. The influences of N-nitro-L-arginine (L-NNA) and L-Arginine (L-AA) on the effect of Ghrelin and GHRP-6 were studied to disclose the mechanism of the effects of Ghrelin and GHRP-6. Results: The circular muscle tissues of the gastric fundus generated on-relaxations and off-contractions when stimulating myenteric plexuses with 1-16 Hz electrical field; the on-responses induced relaxation could be reduced by L-NNA and the off-contractions induced contraction could be blocked by atropine and guanethidine. In fundic strips, ghrelin and GHRP-6 could decrease the on-response induced relaxation and increase off-response induced contraction of the muscle, with the effect of Ghrelin obviously stronger than that of GHRP-6. L-NNA could increase the effects of Ghrelin and GHRP-6-induced muscle contraction, and L-AA could decrease their effects. In the antral strips, electrical field stimulation of myenteric plexuses led to disappearance of relaxation wave, only leaving off-contractions. Both ghrelin and GHRP-6 could increase that contraction. Conclusion: Both ghrelin and GHRP-6 can promote the contractility of stomach smooth muscle in guinea pigs through stimulating myenteric plexuses of gastric fundus and antrium, which might be related to the NO pathway.

BACKGROUND:Besides drug therapy, regenerative therapy is now a matter of global interest in treating osteoporosis. Therefore, it is also important to find better candidate cels. OBJECTIVE:To cognize the status of drug therapies for osteoporosis and stem cels as regenerative therapy. METHODS:A computer-based search of PubMed was performed by the first author to retrieve articles relevant to stem cel therapy for osteoporosis published from January 2000 to December 2014. The keywords were osteoporosis, drug therapy, bone regenerative medicine, stem cel therapy, which appeared in the title, abstract or keywords, and the relevant references were also looked up. Articles published recently or in authoritative journals were preferred, and finaly 39 articles were included in result analysis. RESULTS AND CONCLUSION:Yoshikazu Mikami and co-workers from Japan found two novel bone formation accelerators, SST-VEDI and SSH-BMI, which provides a new direction for related studies on drug therapy. Due to the osteogenesis ability, lack of ethical controversy and less damage, de-differentiated fat cels and pulp stem cels may be promising candidate cels for bone regeneration medicine.

Target volume definition is one of the important factors in precise radiotherapy of esophageal carcinoma.However,there is considerable controversy about delineation of esophageal carcinoma clinical target volume (CTV),and no consistent standard.Recent researches show that pathological characteristics,imaging methods and lymph node metastasis pattern may have guiding functions for CTV delineation.Novel delineation technique such as individual design has been a research hotspot.

?AlM: To observe the changes of corneal topography and astigmatism et al with various duration of closing eyes and sleep;and study the impact of closing eye and sleep causing physiological hypoxia on corneal topography.
? METHODS: Sixteen volunteers were selected ( 32 eyes), 22-33 (26. 19 ± 3. 95) years old, without refractive errors and other eye diseases, as well as never wearing corneal contact lens, including 10 male eyes and 22 female eyes. The main parameters received corneal simulation K value, corneal astigmatism, corneal irregular measure ( ClM ) and the shape factor ( SF ) by Zeiss corneal topographer. They were measured before and after closed eyes 10, 20, 30, 60, 120min; before sleep and after over 6h sleep, they were detected immediately as soon as they opened eyes after 10, 20, 60, 120min.
? RESULTS: During closing eyes, there were no statistical significance on the changes of corneal topography, corneal astigmatism, and SF. After opening eyes and over 6h sleep, there were no statistical significance on the changes of corneal topography, corneal astigmatism, ClM, and SF.
?CONCLUSlON:Closing eyes and sleep don’t injure the cornea substantially, so corneal topography and corneal astigmatism don’t mainly change.