The synchronized HeLa cells were used to study the effect of protein kinase A(PKA) inhibitor on the progression of S phase. Synchronized cell s in S phase were obtained by the method of TdR double block through 3H-T dR incorporation assay. The PKA inhibitor typeⅢ obviously increased the level of 3H-TdR incorporation of S phase in HeLa cells. In contrast with contro l, the activity of thymidine kinase (TK) in S phase increased, too. It indicated that PKA played an inhibitory role in S phase progression of HeLa cells. With t he method of Western blotting, the PKA inhibitor typeⅢ enhanced the level of C yclinA and PCNA, inhibited the expression of p21, which is a negative regulator of cell cycle, but had no effect on the expression of CDK2. The results showed t hat PKA could negatively regulate the S phase progression by affecting the level of CyclinA, PCNA and influencing the expression of p21 protein. This may be one of the molecular mechanisms which is involved in the negative regulation of S p hase progression by PKA in HeLa cells.

Clinical data of 129 young pafienm with lung cancer were analyzed retrospectively.Adenocarcinoma was the main pathologic type of lung cancer(n=62,48.1%),followed by undifferentiated small cell carcinoma(n=35,27.1%),squamous carcinoma(n=20,15.5%).Forty four cases were misdiagnosed at first consultation with a misdiagnosis rate of 34.1%.To avoid misdiagnosis seems to be the key issue for improvement of prognosis in young patients with lung cancer.

Objective To investigate the clinical and imaging features in patients with vertebrobasilar dolichoectasia (VBD) through a comparative study in patients with ischemic stroke with or without VBD.Methods The patients with acute cerebral infarction were divided into either a VBD group or a non-VBD group according to magnetic resonance angiography.The VBD group was further divided into an anterior circulation infarction subgroup and a posterior circulation infarction subgroup.The cardiovascular risk factors,the diameter of basiar artery (BA),bifurcation height,and horizontal displacement were compared in all groups.Results A total of 269 patients with acute cerebral infarction were included,28 had VBD,accounting for 10.41％ of the patients with acute cerebral infarction during the same period.The proportion of male patients (78.6％ vs.66.8％ ;x2 =4.392,P =0.036),age (70.38 ± 10.58 years vs.62.86 ± 12.20 years; t =2.870,P =0.009),and the proportion of hypertension (89.3％ vs.47.7％ ; x2 =17.367,P =0.000) in the VBD group were significantly higher than those in the non-VBD group.The multivariate logistic regression analysis showed that the advanced age (odds ratio [OR] 1.248,95％ confidence interval [CI] 1.137-1.371; P=0.000),hyperglycemia (OR 1.599,95％ CI 1.181-2.164; P =0.002),hypertension (OR 1.251,95％ CI 1.020-1.534; P =0.032) and increased triglyceride level (OR 1.876,95％ CT 1.021-3.445; P =0.043) were the independent risk factors for VBD,while female gender (OR 0.133,95％ CI 0.024-0.735; P =0.021) was the independent protective factor for VBD.Of the 28 cerebral infarction patients with VBD,9 had anterior circulation infarction and 19 had posterior circulation infarction.There were significant differences in BA diameter ([5.40 ± 0.49] cm vs.[6.00 ± 0.77] cm; t =2.046,P =0.041),and the proportions of high score in bifurcation height (x2 =6.768,P =0.037) and horizontal displacement (x2 =5.241,P =0.042) between the 2 groups (all P ＜0.05).The multivafiate logistic regression analysis showed that the BA bifurcation height was an independent risk factor for posterior circulation infarction (OR 1.347,95％ CI 1.069-2.457; P =0.038) in patients with VBD.Conclusions VBD accounted for 10.41％ of the patients with acute cerebral infarction during the same period.Advanced age,hyperglycemia,hypertension and increased triglyceride level were the independent risk factors for VBD.Female gender was the independent protective factors for VBD,and the BA bifurcation height was an independent risk factor for VBD occurring posterior circulation infarction.