ObjectiveTo investigate the associations of plasma homocysteine (Hcy) and lipoprotein-associated phospholipase A2 (Lp-PLA2) levels with dementia.MethodsThe patients with dementia admitted to hospital were enrolled retrospectively.They were divided into a vascular dementia (VaD) group, a mixed dementia (MD) group, and an Alzheimer's disease (AD) group according to the Hachinski Ischemic Score, and the dementia severity was further divided into a mild group, a moderate group and a severe group according to the Mini-Mental State Examination.The non-demented patients hospitalized during the same period were selected as controls.The demographics, vascular risk factors, and plasma Hcy and Lp-PLA2 levels in each group were compared.Logistic regression analysis was used to determine the independent associations of the plasma Hcy and Lp-PLA2 levels with the risk of dementia and severity.ResultsA total of 125 patients with dementia were enrolled, including 52 (41.6%) in the VaD group, 21 (16.8%) in the MD group, and 53 (41.6%) in the AD group.There were 49 patients (39.2%) in the mild group, 51 (40.8%) in the moderate group, and 25 (20%) in the severe group.A total of 40 non-demented patients were enrolled as control group.The plasma Hcy and Lp-PLA2 levels in VaD, MD and AD groups were significantly higher than those in the control group (all P<0.001).Multivariable logistic regression analysis showed that the advanced age (odds ratio[OR] 1.12, 95% confidence interval [CI] 1.03-1.21;P=0.010), high plasma Hcy level (OR 1.44, 95% CI 1.21-1.71;P<0.001), high Lp-PLA2 level (OR 1.01, 95% CI 1.00-1.02;P=0.006), and previous stroke (OR 4.29, 95% CI 1.50-12.36;P=0.007) were the independent risk factors for dementia;high Hcy level (OR 1.48, 95% CI 1.21-1.82;P<0.001, high Lp-PLA2 level (OR 1.01, 95% CI 1.00-1.03;P=0.002), and previous stroke (OR 152.78, 95% CI 20.41-999.97;P<0.001) were the independent risk factors for VaD;advanced age (OR 1.10, 95% CI 1.02-1.17;P=0.008) and high Hcy level (OR 1.41, 95% CI 1.25-1.58;P<0.001) were the independent risk factor for severe dementia.ConclusionsThe increased plasma Hcy and Lp-PLA2 levels are associated with dementia.Reducing the plasma Hcy and Lp-PLA2 levels may be beneficial to the treatment and prevention of dementia.

Objective To estimate the effect of itermittent subglottic secretions drainage(ISSD)on management of artificial airway to prevent tube-related pulmonary pneumonia.Methods One hundred ICU patients with intubation for artificial airway were divided equally into control and experiment group by random digits table.Both were managed with construction of artificial airway and besides the experiment group received ISSD. The two groups were compared in terms of incidence and occurrence time of catheter-related pneumonia, time for airway opening and ICU stay.Result The incidence and the occurrence time of pneumonia, time for airway opening and ICU stay time in the experiment group were significantly lower or shorter than those in the control group with statistical difference(all P<0.05).Conclusion ISSD is effective in decreasing the incidence of catheter related pneumonia, shortening the occurrence time of catheter related pneumonia and ICU stay time for the patients with artificial airway.

Objective To investigate the effects of recombinant tissue plasminogen activator (rt-PA)intravenous thrombolysis on blood-brain barrier (BBB) permeability,the expressions and the activities of MMP-2 and MMP-9 after cerebral ischemia in rats.Methods A total of 40 adult male Sprague-Dawley rats were allocated into 3 groups:Sham operation group (n =10),middle cerebral artery occlusion (MCAO) group (n =18),and rt-PA thrombolysis group (n =18).A MCAO model was established by using autologous thromboembolism.The sham operation group did not inject any thromboembolus,the MCAO group only made MCAO,and the rt-PA thrombolysis group received intravenous thrombolysis with rt-PA at 3 hours after MCAO.Brain infarct volume was determined by 2,3,5-triphenyl tetrazolium chloride staining BBB permeability was measured by Evans blue dye leakage.The activities and the expressions of MMP-2 and MMP-9 in brain tissue were detected by Gelatin zymography and Western blot,respectively.Results Compared to the MCAO group,the neurological function was improved significantly in the rt-PA thrombolysis group,and the infarct volume was also reduced significantly (t =7.365,P =0.005).However,the hemorrhage score (t =-3.286,P =0.017) and BBB permeability (t =-3.947,P =0.029) were increased significantly.The activities and the expressions of MMP-2 and MMP-9 in the sham operation group were lower.The activities and the expressions of MMP-2 (t =-45.121,P =0.000; t =-11.624,P=0.000) and MMP-9 (t=-71.849,P=0.000; t=-8.992,P=0.000) in the MCAO group were increased and upregulated significantly.Compared to the MCAO group,the activities and the expressions of MMP-2 (t =-28.792,P =0.000; t =-3.809,P =0.013) and MMP-9 (t =-53.506,P =0.000; t =-2.640,P =0.046) in the rt-PA thrombolysis group were increased and upregulated significantly.Conclusions After rt-PA intravenous thrombolytic therapy,the BBB permeability was increased.The activities and the expressions of MMP-2 and MMP-9 were increased and upregulated.MMP-2 and MMP-9 might participate in the increased BBB permeability,and thus inducing hemorrhagic transformation after rt-PA intravenous thrombolytic therapy in rats with cerebral ischemia.

Objective To establish and validate a modified rat thromboembolic stroke model.Methods After taking femoral arterial blood and mixing it with thrombin,they were injected into PE-50 catheter for preparing in vitro thrombosis in 60 Sprague-Dawley rats.A thromboembolic cerebral ischemia model induced by catheterization of the right external carotid artery and the small blood clot emboli were injected into the internal carotid arteries.Thirty rats were randomly divided into a large number of emboli group (n =10 with 12 emboli),a median number of emboli group (n =10 with 10 emboli) and a small number of emboli group (n =10 with 8 emboli).Two hours after embolus injection,the neurological deficit score was performed and the success rate of the model was compared in all groups.Twenty-four hours after embolus injection,the rats were sacrificed and the brains were removed for 2,3,5-triphenyltetrazolium chloride staining.The hemorrhage,infarct volume,bleeding incidence and mortality after cerebral infarction were evaluated.The high success rates of the modeling in the emboli groups were selected and they were randomly divided into either a normal saline group (n =12) or a recombinant tissue-type plasminogen activator (rtPA) group (n =12).The rats were given normal saline and rtPA at 3 hours after embolus injection.Before embolus injection and 2,6,12 and 24 hours after embolus injection,the neurological scores were performed respectively; 24 hours after embolus injection,the rats were sacrificed and the brains were removed for 2,3,5-triphenyltetrazolium chloride staining.The hemorrhage rate,infarction size,degree of cerebral edema,and blood-brain barrier permeability were evaluated.Results Only 40％ of rats had neurological deficits in the small number of emboli group,and the infarct volume was only 10.54 ± 2.82％.The success rates in the median and large number of emboli groups were 80％ and 100％ respectively.They were all significantly higher than those in the small number of emboli group (P =0.011 ).The infarct volume was also significantly greater than that in the small number of emboli group (F =40.897,P =0.000).After administration of rtPA,the mean survival time of the rats in the large number of emboli group was less than 24 hours,so the median number of emboli group was selected to study the thrombolytic effect of rtPA.The infarct volume and neurological function score in the rtPA group were improved significantly compared to the normal saline group (t =7.728,P =0.000),while there were no significant differences in the hemorrhage rate,degree of brain edema and blood-brain barrier permeability between the 2 groups.Conclusions The stability and reproducibility were good in the modified thromboembolic cerebral ischemia model injected with 10 emboli,the neurological function was improved significantly after thrombolysis,and it was applicable to the experimental study of pathophysiology of cerebral ischemia and thrombolytic therapy.

Objective To investigate the effects of mycoplasma pneumoniae(MP)infection on the exhaled nitric oxide level and lung function in asthmatic children,analyze the correlation between exhaled nitric oxide level and lung function and to provide reference for the treatment and monitoring of asthmatic children.Methods Sixty-eight children aged from 5 to 13 years old with mild or moderate asthma during June 2011 to January 2013 were collected.MP-IgG antibody,MP-IgM antibody,MP-DNA,total serum IgE,FeNO measurement and spirometry were examined on the next day morning.They were divided into two groups according to the pathogen:ashtma with MP group and ashtma without MP group.Then the levels of nitric oxide level and lung function indicators between the two groups were analyzed.Results The FeNO level in ashtma with MP group was significantly higher(P<0.05).There were no differences between two groups in lung function parameters such as FVC,FEV1,FEV1 / Vcmax,MEF25 and MEF50(P>0.05),but differnces were found in MEF75 and PEF(P<0.05).No correlation was found between FeNO levels and lung function parameters(FVC,FEV1,FEV1/Vcmax,MEF50,MEF25,MEF75 and PEF).Conclusion In asthma children with MP infection,the FeNO level was significantly increased and no correlation was found between FeNO levels and lung function.

Objective:To investigate changes in circadian gene cryptochrome 2 (CRY2) expression in mouse models of psoriasis and HaCaT cells, and to explore underlying mechanisms.Methods:Imiquimod-induced mouse model experiment: 12 C57BL/6 female mice were randomly and equally divided into imiquimod group receiving topical imiquimod treatment for 5 consecutive days and control group receiving no treatment; these mice were sacrificed on day 6, skin tissues were resected from the back of mice, and immunofluorescence staining was performed to determine the CRY2 expression in the epidermis. HaCaT cell transfection experiment: HaCaT cells with small interfering RNA (siRNA) -mediated knockdown of CRY2 served as siRNA-CRY2 group, and siRNA-NC group as control group; 5-ethynyl-2′-deoxyuridine (EdU) staining was performed to evaluate the proliferative activity of the HaCaT cells, real-time fluorescence-based quantitative PCR (qPCR) to determine the mRNA expression of chemokines in the HaCaT cells, and Western blot analysis to determine phosphorylation levels of extracellular signal-regulated kinase 1/2 (ERK1/2) . Tumor necrosis factor-α (TNF-α) -stimulated animal and cell experiments: 12 C57BL/6 female mice were randomly and equally divided into TNF-α group subcutaneously injected with TNF-α solution in the ear for 6 days, and phosphate buffered saline (PBS) group subcutaneously injected with the same amount of PBS; the mice were sacrificed on day 7, skin tissues were resected from the ear of mice, and immunofluorescence staining was conducted to determine the CRY2 expression in the epidermis; CRY2-knockdown HaCaT cells stimulated with 50 ng/ml TNF-α for 12 hours served as siRNA-CRY2 + TNF-α group, and siRNA-NC + TNF-α group as control group; qPCR was performed to determine the mRNA expression of chemokines in HaCaT cells in the above groups. Statistical analysis was carried out by using two-independent-sample t test. Results:Immunofluorescence staining showed that the CRY2 protein expression was significantly lower in the mouse dorsal epidermis in the imiquimod group (0.94 ± 0.23) than in the control group (2.30 ± 0.25, t = 3.99, P = 0.016) . Compared with the siRNA-NC group, the siRNA-CRY2 group showed significantly increased proportions of EdU-positive cells (48.13% ± 10.97% vs. 38.23% ± 0.81%, t = 5.00, P = 0.007) , mRNA expression levels of chemokines CXCL1 and CXCL8, as well as significantly increased phosphorylated (p) -ERK1/2 protein expression levels (all P < 0.05) , while there were no significant differences in the CCL20 mRNA expression or ERK1/2 protein expression between the two groups (both P > 0.05) . Immunofluorescence staining showed significantly decreased CRY2 protein expression level in the mouse ear epidermis in the TNF-α group (0.37 ± 0.34) compared with the PBS group (2.04 ± 0.17, t = 4.38, P = 0.012) ; the relative mRNA expression levels of chemokines CXCL1, CXCL8, and CCL20 in HaCaT cells were significantly higher in the siRNA-CRY2 + TNF-α group than in the siRNA-NC + TNF-α group (all P < 0.05) . Conclusion:CRY2 was markedly underexpressed in psoriasis, which might promote the proliferation of keratinocytes and expression of chemokines CXCL1, CXCL8 and CCL20, and TNF-α might be an upstream cytokine that could downregulate CRY2 expression.