Effects of thrombin on the secondary cerebral injury of perihematomal tissues of rats after intracerebral hemorrhage.

This study aimed to investigate the effects of thrombin released in hematoma after intracerebral hemorrhage (ICH) on the cerebral injury of perihematomal tissues and to evaluate the protection effect of hirudin on the cerebral injury after ICH. We used the autologous uncoagulated blood injection method to prepare the ICH rat model, and all rats were randomly divided into a normal group, an ICH group, or a hirudin group. At different time points, rat heads were cut to harvest brain sections. Immunohistochemical staining, histochemical staining, and hematoxylin and eosin staining were conducted for CD34, microglia, and neutrocytes. CD34-positive microvessels were most abundant in brain tissues of the sham-operation group. At 12 h after ICH, CD34 expression reduced and reached the minimum level at 72 h (P<0.01). At 6 h after ICH, microglia expression was visible and reached a peak at 48 h (P<0.01). At 12 h after ICH, neutrocyte infiltration was visible and the number was greatest at 48 h (P<0.01). The early application of hirudin after ICH could significantly reduce microglia and neutrocyte expression and could significantly slow down the CD34 decrease trend (P<0.01). However, hirudin application in the edematization stage after ICH did not significantly increase CD34- positive microvessel abundance (P>0.05). A thrombin-mediated inflammatory reaction is involved in the cerebral injury after ICH, and the early application of hirudin has a protective effect.

[Confidence factors-method for estimating the confidence limits of standardized population rate of indirect method].

The standardized rate of indirect method is widely used, but no method of interval estimation for its population rate has been reported. The authors have discussed the standard error of standardized rate of indirect method and suggested that a method using this standard error should be used to determine the confidence limits for the population rate. In this paper, the authors put forward another method (Confidence Factors-Method) which can be easily applied to determine the confidence limits. It gives approximately the same result with the method mentioned above.

[Rank transformations--the connection between nonparametric and parametric statistics].

The purpose of this paper is to present the relationship between nonparametric and parametric analysis by means of rank transformation. It is shown that in case of large sample, the resulting statistics getting from Wilcoxon rank test, Kruskal-Wallis and Friedman rank test are equivalent to the ratio of the sum of squares for treatment divided by mean square for the total variability calculated by ranks in the manner of the analysis of variance. It is also suggested that this method can be extended to factorial design experiments, and a detail procedure is given.

FoxM1 regulates Sirt1 expression in glioma cells.

BACKGROUND AND OBJECTIVES: Glioma accounts for most of primary malignant brain tumors and usually results in poor survival. However, the key signaling networks regulating glioma cell proliferation remain poorly defined. The forkhead box M1 (FoxM1) is a key transcription factor regulating multiple aspects of cell biology. Prior studies have shown that FoxM1 is overexpressed in glioma and plays a critical role in cancer development and progression. MATERIALS AND METHODS: Western blot and Real-time PCR assays were used to determine the regulation roles of FoxM1 on Sirt1 (Sirtuin1) expression. Small interfering RNAs (siRNAs) were used to silence the expression of FoxM1. Luciferase assays were used to measure binding of FoxM1 to the promoter region of Sirt1. Direct binding of FoxM1 to promoter of Sirt1 was assessed by chromatin immunoprecipitation (CHIP) assays. RESULTS: We found that FoxM1 positively regulated mRNA expression of Sirt1. FoxM1 overexpression promoted while its knockdown inhibited Sirt1 expression. Besides, we identified a minimal FoxM1 binding site on the promoter region of Sirt1. CONCLUSIONS: Our results for the first time add a new FoxM1-Sirt1 connection that mediates cell proliferation in glioma.

[Protective effects of scopolamine on rabbits with acute brain injury].

OBJECTIVE: To study the protective effects of scopolamine (Sco) (a muscarinic receptor antagonist) on rabbits with acute brain injury, and preliminarily explore the roles of acetylcholine (ACh) in the early pathologic changes of traumatic brain injury(TBI). METHODS: The model of acute brain injury was established by a free-falling device, and the rabbits received Sco intraperitoneally at 5 minutes and 2 hours after brain injury respectively. Transcranial Doppler (TCD) was used to monitor cerebral blood flow velocity (CBV) and pulsatility index (PI) of middle cerebral artery (MCA). The levels of Ca2+, the activities of superoxide dismutase (SOD), the contents of malondiadehyde (MDA) and Evans blue (EB) were measured, and the pathological changes were observed in brain tissue. RESULTS: This model consisted with the pathologic changes of accelerated brain injury. Sco reduced the levels of Ca2+, EB and MDA, increased the activities of SOD, and improved cerebral blood flow following brain injury. CONCLUSIONS: In the early stage of brain injury, ACh can cause neuron calcium overload, oxide free radical reaction, cerebral vasospasm, and increase blood-brain barry(BBB) permeability. Scopolamine, a muscarinic receptor antagonist, can improve these pathologic changes. As a result, Sco has protective effects on brain tissue injury.