Klotho inhibits the activation of NLRP3 inflammasome to alleviate lipopolysaccharide-induced inflammatory injury in A549 cells and restore mitochondrial function through SIRT1/Nrf2 signaling pathway.

Acute lung injury is a severe clinical condition constituting a major cause of mortality in intensive care units. This study aimed to investigate the role of klotho in alleviating lipopolysaccharide (LPS)-induced acute lung injury. LPS-induced acute lung injury was used to simulate the acute lung injury caused by severe pneumonia in vitro. The viability and apoptosis of A549 cells were detected by cell counting kit-8 assay and flow cytometry. The inflammatory response, oxidative stress, and mitochondrial function in A549 cells were analyzed by commercial assay kits and 5,5',6,6'-tetrachloro-1,1',3,3'-tetraethyl-benzimidazolyl carbocyanine iodide (JC-1) staining. The expression of apoptosis-related proteins, Sirtuin 1 (SIRT1)/nuclear factor erythroid 2-related factor 2 (Nrf2) signaling pathway-related proteins, and NOD-like receptor family pyrin domain containing 3 (NLRP3) expression in A549 cells was detected by western blot. The mtDNA synthase level in A549 cells was analyzed by reverse transcription-quantitative polymerase chain reaction. The results showed that, klotho had no cytotoxic effect on A549 cells. The viability and mitochondrial function were inhibited and apoptosis, inflammatory response, and oxidative stress were aggravated in LPS-induced A549 cells, which were all reversed by klotho. Klotho activated the SIRT1/Nrf2 signaling pathway to inhibit the LPS-induced NLRP3 inflammasome activation in A549 cells. However, EX527, a SIRT1 inhibitor, attenuated the klotho effect to suppress viability and mitochondrial function and promoted apoptosis, inflammatory response, and oxidative stress of A549 cells. In conclusion, klotho inhibited the activation of NLRP3 inflammasome to alleviate LPS-induced inflammatory injury of A549 cells and restore mitochondrial function through activating the SIRT1/Nrf2 signaling pathway.

NETs promote ALI/ARDS inflammation by regulating alveolar macrophage polarization.

Neutrophils activated during acute lung injury (ALI) form neutrophil extracellular traps (NETs) to capture pathogens. However, excessive NETs can cause severe inflammatory reactions. Macrophages are classified as M1 macrophages with proinflammatory effects or M2 macrophages with anti-inflammatory effects. During ALI, alveolar macrophages (AMs) polarize to the M1 phenotype. This study tested the hypothesis that NETs may aggravate ALI or acute respiratory distress syndrome (ARDS) inflammation by promoting alveolar macrophage polarization to the M1 type. Our research was carried out in three aspects: clinical research, animal experiments and in vitro experiments. We determined that NET levels in ARDS patients were positively correlated with M1-like macrophage polarization. NET formation was detected in murine ALI tissue and associated with increased M1 markers and decreased M2 markers in BALF and lung tissue. Treatment with NET inhibitors significantly inhibitor NETs generation, downregulated M1 markers and upregulated M2 markers. Regardless of LPS pre-stimulation, significant secretion of proinflammatory cytokines and upregulated M1 markers were detected from bone marrow-derived macrophages (M0 and M2) cocultured with high concentrations of NETs; conversely, M2 markers were downregulated. In conclusion, NETs promote ARDS inflammation during the acute phase by promoting macrophage polarization to the M1 phenotype. We propose that NETs play an important role in the interaction between neutrophils and macrophages during the early acute phase of ALI.

PKR suppress NLRP3-pyroptosis pathway in lipopolysaccharide-induced acute lung injury model of mice.

To explore the effect of double-stranded RNA-dependent kinase (PKR) in acute lung injury (ALI) and resultant acute respiratory distress syndrome (ARDS). A mouse model of lipopolysaccharide (LPS)-induced ALI was used to evaluate the levels of phosphorylated (p)-PKR and NLRP3 in lung tissue, and the protective effects of a PKR inhibitor on lung injury. And in vitro, macrophages were incubated with LPS, with or without PKR inhibitor pre-treatment. It was observed that the levels of p-PKR protein and NLRP3 protein were significantly increased compared with those in control tissues after LPS administration. Meanwhile, treatment with PKR inhibitor decreased inflammation, injury score, wet/dry weight ratio, bronchoalveolar lavage fluid (BALF) protein levels, neutrophil count in BALF, myeloperoxidase activity and expression of high-mobility group box1(HMGB1) and interleukin(IL)-1ß in the lungs of LPS-challenged mice. In vitro, we demonstrated that the levels of p-PKR and NLRP3, and cell mortality rate were increased in macrophages which were incubated with LPS compared with those without LPS administration, and PKR inhibitor significantly suppressed the level of NLRP3, caspase-1, HMGB1 and IL-1ß. These results indicate that PKR plays a key role in ALI through NLRP3-pyrotosis pathway and pharmacological inhibition of PKR may have potential therapeutic effects in the treatment of patients with ALI and ARDS.

Simulated coronary arterial hemodynamics of myocardial bridging.

The objective of this study was to explore the effects of myocardial bridge compression on blood flow, normal stress, circumferential stress and shear stress in mural coronary artery. An original mural coronary artery simulative device has been greatly improved and its measured hemodynamic parameters have been expanded from a single stress (normal stress) to multiple stresses to more fully and accurately simulate the true hemodynamic environment under normal stress, circumferential stress and shear stress. This device was used to more fully explore the relationship between hemodynamics and mural coronary atherosclerosis under the combined effects of multiple stresses. Results obtained from the mural coronary artery simulator showed stress abnormality to be mainly located in the proximal mural coronary artery where myocardial bridge compression was intensified and average and fluctuation values (maximum minus minimum) of proximal stress were significantly increased by 27.8% and 139%, respectively. It is concluded that myocardial bridge compression causes abnormalities in the proximal hemodynamics of the mural coronary artery. This is of great significance for understanding the hemodynamic mechanism of coronary atherosclerosis and has potential clinical value for the pathological effect and treatment of myocardial bridge.

Investigating the relationship between 25-hydroxyvitamin D and thyroid function in second-trimester pregnant women.

This study aims to explore the correlation between serum 25-hydroxyvitamin D and thyroid hormones during the second trimester. In total, 277 pregnant women at 13-28 weeks of gestation were enrolled. According to the level of thyrotropic-stimulating hormone, they were divided into a reduced TSH group, a normal TSH group and an elevated TSH group. In this study, we found that the prevalence of vitamin D deficiency was as high as 94.58%. The 25-hydroxyvitamin D level in the reduced TSH group was lower than that in the normal thyroid function group (p = .0005), and the 25-hydroxyvitamin D level in the elevated TSH group was higher than that in normal TSH group (p=.0339). A positive correlation was observed between 25-hydroxyvitamin D and thyrotropic-stimulating hormone (r = 0.3034, p = .0000). Furthermore, 25-hydroxyvitamin D was negatively correlated with the free thyroxine level (r = -0.1286, p = .0323) as well as the free triiodothyronine level (r = 0.1247, p = .0380). These data suggest that the relationships between 25-hydroxyvitamin D and thyroid parameters were characterized during the second trimester. Pregnant women in the second-trimester who are diagnosed with transient hyperthyroidism should be evaluated for the possibility of vitamin D deficiency.

Changes of Number and Function of Late Endothelial Progenitor Cells in Peripheral Blood of COPD Patients Combined with Pulmonary Hypertension.

Objective The objective of this study was to investigate the changes of number and function of late endothelial progenitor cells (EPCs) in peripheral blood of chronic obstructive pulmonary disease (COPD) patients combined with pulmonary hypertension. Subjects and Methods The study enrolled 120 cases including 40 non-COPD and pulmonary arterial hypertension (PAH) patients (non-COPD group), 40 COPD non-PAH patients (COPD group), and 40 COPD patients combined with PAH (COPD + PAH group). Peripheral blood mononuclear cells were separated by density gradient centrifugation, cultured for 21 days, and then identified as late endothelial progenitor cells. The cell colonies were counted. MTT assay, modified Boyden chamber assay, and human fibronectin plates were used to measure the proliferation, migration, and adhesion functions of the late endothelial progenitor cells, respectively. Results Compared with non-COPD and COPD groups, the number of peripheral blood late EPCs in COPD + PAH group was significantly reduced, and the proliferation, adhesion, and migration capacities were significantly lowered; the differences were statistically significant (p < 0.05). The number and function of late EPCs decreased with the increase of pulmonary artery pressure (p < 0.05). Conclusion The number of late EPCs in COPD patients combined with pulmonary hypertension was reduced, which implies the impaired cell functions. The changes of number and function were negatively correlated with the severity of pulmonary hypertension.

Hypothermia stimulates glioma stem spheres to spontaneously dedifferentiate adjacent non-stem glioma cells.

Current models of stem cell biology assume that glioma stem cells reside at the apices of hierarchies and differentiate into non-stem progeny in a unidirectional manner. However, here we found an opposite phenomenon that glioma stem spheres could induce adjacent non-stem glioma cells to spontaneously dedifferentiate into stem-like cells in low temperature condition. In low temperature condition, it has been reported that mild hypothermia could induce pluripotent stem cells in hESC and iPSC. However, till now, its effects on glioma stem cells were still unknown. In this study, tracking the non-stem cells, we found that they could be attracted by stem spheres, and finally enter the stem spheres to become a member of stem spheres in vitro. However, these induced stem-like cells positive of CD133 and Nestin markers could not form an obvious sphere. To better understand the genetic differences of the stem spheres and stem-like cells underlying the change of microenvironment, we carried out Cytokine antibody array, Cancer PathwayFinder PCR array, and miRNA chip array, which demonstrated that lots of cytokines, mRNAs, and miRNAs involved in this microenvironmental change. In this study, the most important discovery by us was that we found GSCs sphere cores, which has been found to have strong proliferative capacity, and be able to 100 % form a big GSCs sphere. We hope these findings can change our past concepts, and be help to the further research on gliomas stem cells, and GSCs sphere cores can be defined as the primitive stem cells for further research.

Redisplacement after reduction with intramedullary nails in surgery of intertrochanteric fracture: cause analysis and preventive measures.

OBJECTIVE: During the implantation of intramedullary nail in surgery of intertrochanteric fracture, the fact that the originally satisfactory reduction may incur redisplacement remains a major concern. In this article, we will analyze the reasons of redisplacement and describe some methods that can improve the quality of reduction. METHODS: From January 2012 to October 2014, 67 patients with intertrochanteric fracture were treated using Gamma3 or PFNA system. All the surgical procedures were monitored by fluoroscopy on the AP and lateral views, and the X-ray films were used to evaluate all cases. RESULTS: Redisplacement occurred in ten cases intraoperatively. According to the fracture type, re-occurring deformities appeared in 31-A2 and 31-A3 commonly, 6 and 3 cases. We found the redisplacement emerged usually in operative procedure and some manipulations should be taken to obtain an anatomic reduction. CONCLUSIONS: When reduction is achieved in the surgery of intertrochanteric fracture, surgeons tend to overlook the occurrence of redisplacement, or not to treat it that has emerged timely. Internal fixation in nonanatomic reduction may increase the likelihood of fixation failure postoperatively. For the importance of accurate reduction of the fracture, once redisplacement occurs during the surgery, some methods or tricks are applicable to it to restore the anatomic reduction.

Comparison of the ablation ability of nucleus pulposus after 1,064 nm Nd:YAG laser and 980 nm diode laser radiation.

OBJECTIVE: To compare the ablation ability of nucleus pulposus after 1,064 nm Nd:YAG laser and 980 nm diode laser radiation. METHODS: Goat spine specimen (GSS) was radiated using Nd:YAG laser and 980 nm diode laser and then divided into five groups based on the final energy--200, 400, 600, 800 and 1,000 J groups. The ablation quality of nucleus pulposus after radiation was recorded. RESULTS: The ablation quality of GSS was greater at higher radiation energies in both lasers. When compared at the same energy level, the ablation quality of GSS was greater in 980 nm diode laser than in 1,064 nm Nd:YAG laser. Statistical significance was observed in 200 and 400 J groups (P < 0.05) and in 600, 800 and 1,000 J groups (P < 0.01). CONCLUSION: Radiation with 980 nm diode laser showed better ablation ability than 1,064 nm Nd:YAG laser.

Applying support vector regression analysis on grip force level-related corticomuscular coherence.

Voluntary motor performance is the result of cortical commands driving muscle actions. Corticomuscular coherence can be used to examine the functional coupling or communication between human brain and muscles. To investigate the effects of grip force level on corticomuscular coherence in an accessory muscle, this study proposed an expanded support vector regression (ESVR) algorithm to quantify the coherence between electroencephalogram (EEG) from sensorimotor cortex and surface electromyogram (EMG) from brachioradialis in upper limb. A measure called coherence proportion was introduced to compare the corticomuscular coherence in the alpha (7-15Hz), beta (15-30Hz) and gamma (30-45Hz) band at 25 % maximum grip force (MGF) and 75 % MGF. Results show that ESVR could reduce the influence of deflected signals and summarize the overall behavior of multiple coherence curves. Coherence proportion is more sensitive to grip force level than coherence area. The significantly higher corticomuscular coherence occurred in the alpha (p < 0.01) and beta band (p < 0.01) during 75 % MGF, but in the gamma band (p < 0.01) during 25 % MGF. The results suggest that sensorimotor cortex might control the activity of an accessory muscle for hand grip with increased grip intensity by changing functional corticomuscular coupling at certain frequency bands (alpha, beta and gamma bands).

The role of coupling strength and internal delay between compartments in shaping the bursting behavior of cortical neuron.

Bursting is a typical firing behavior intrinsically existing in neurons from many brain regions, which has been thought to have functional roles in neuronal reliable signaling and synaptic plasticity. Meanwhile, many factors have been put forward to participate in the modulation of bursting behavior during the past decades. Here, in this research, the modulation of bursting behaviors was numerically investigated in a two-compartment model of cortical pyramidal neuron using the coupling strength and time delay between compartments as control parameters. By means of computer simulations, we showed that, for larger coupling strengths and smaller delays between the two compartments, a wide range of regular bursting can be observed, while too large coupling strengths and time delays would cause the model neuron to be quiescent. In addition, the dynamical firing range of regular spiking can be also obtained, which has two parts: one part corresponds to small coupling strengths irrespective of the values of time delay, while another part corresponds to larger coupling strengths and delays. These results suggested that coupling strength and internal time delay between the inner compartments possess potential roles in modulating the dynamical bursting behavior of neurons.

Efficacy of percutaneous laser disc decompression on lumbar spinal stenosis.

The objective of this study is to observe the effect of percutaneous laser disc decompression (PLDD) on lumbar spinal stenosis (LSS). Thirty-two LSS patients were treated using pulsed Nd: YAG laser, of which 21 cases (11 males and 10 females with an average age of 64 years old) were followed up for 2 years. All of the 21 patients had intermittent claudication with negative straight leg raising test results. Fifteen patients suffered from anterior central disc herniation which often compressed the cauda equina but seldom compressed the posterior part; six patients suffered from posterior ligamentum flavum hypertrophy which often compressed the cauda equina but seldom compressed the anterior part. The efficacy was evaluated 1, 3, 6, 12 and 24 months after surgery on 21 patients using the performance evaluation criteria of the lumbago treatment by the Japanese Orthopaedic Association (JOA 29 scores). The fineness (i.e. excellent and good treatment outcome) rate 1, 3, 6, 12 and 24 months after the operation were 46.7%, 66.7%, 66.7%, 66.7% and 66.7%, respectively, in patients with severe anterior compression and 16.7%, 33.3%, 33.3%, 33.3% and 33.3%, respectively, in patients with severe posterior compression. PLDD had certain positive efficacy on the treatment of lumbar spinal stenosis, which was more significant on LSS dominated by the anterior compression than that by the posterior compression.

Circulating microRNAs as novel potential biomarkers for early diagnosis of acute stroke in humans.

BACKGROUND: Many diseases include microRNAs (miRNAs) as reported biomarkers. The significance of circulating miRNAs for early diagnosis of acute stroke in humans is unknown. We aim to determine whether circulating miRNAs potentially serve as novel biomarkers for acute stroke. METHODS: We prospectively recruited patients with acute stroke and those with nonstroke disease. Patients with acute stroke were identified using magnetic resonance imaging (MRI) for early diagnosis. If the patient suffered from acute stroke that was detected with diffusion-weighted imaging, the patient was defined as an MRI(+) patient. Otherwise, it was defined as an MRI(-) patient. Circulating miRNAs were measured by miRNA microarray and real-time polymerase chain reaction (PCR) analysis. RESULTS: A total of 136 patients were included in the study. Testing by miRNA microarray and real-time PCR analyses showed that hsa-miR-106b-5P and hsa-miR-4306 were present with markedly high abundance in patients of acute stroke, whereas hsa-miR-320e and hsa-miR-320d were present with quite low abundance in patients compared with healthy individuals. Compared with healthy individuals, the miRNAs were increased as in patients with acute stroke as follows: hsa-miR-106b-5P, 3.63-fold in MRI(-) patients and 23.90-fold in MRI(+) patients; hsa-miR-4306, 3.19-fold in MRI(-) patients and 5.30-fold in MRI(+) patients; hsa-miR-320e, .33-fold in MRI(-) patients and .13-fold in MRI(+) patients; and hsa-miR-320d, .23-fold in MRI(-) patients and .07-fold in MRI(+) patients. CONCLUSIONS: Elevated hsa-miR-106b-5P and hsa-miR-4306 and decreased hsa-miR-320e and hsa-miR-320d in plasma may be novel biomarkers for the early detection of acute stroke in humans.

Mid-term efficacy of percutaneous laser disc decompression for treatment of cervical vertigo.

OBJECTIVE: To observe and analyze the mid-term efficacy of percutaneous laser disc decompression (PLDD) for the treatment of cervical vertigo. METHODS: Thirty-five patients with cervical vertigo were admitted from September 2002 to December 2006, including 14 males and 21 females, aged between 35 and 79 years with an average of 59.1 years. All patients were treated with PLDD by the Nd:YAG laser therapy (wavelength: 1,064 nm) and were followed up. The improvement of vertigo and associated symptoms was evaluated by numerical rating scale (NRS) assessment, while fineness rate and efficient rate were evaluated using modified MacNab assessment criteria. RESULTS: No intraoperative and postoperative complication was reported. The patients were followed up for 24-66 months. At the end of the follow-up, the average NRS scores of the dizziness and complications are significantly smaller. The overall efficacy was evaluated based on modified MacNab criteria: excellent, 18 cases; good, 7 cases; acceptable, 5 cases; and poor, 5 cases. No statistical difference existed between age groups (P > 0.05) and also between gender groups (P > 0.05). CONCLUSION: PLDD treatment of cervical vertigo trauma has many advantages, such as minimal trauma, high safety, and satisfactory mid-term efficacy with no significant difference in clinical efficacy between different age and gender groups.

Arthroscopic findings in the recurrent anterior instability of the shoulder.

BACKGROUND: A recurrent anterior shoulder dislocation consists of a variety of lesion types. OBJECTIVES: To evaluate the pathological classification of recurrent anterior dislocation of the shoulder joint under arthroscopy. METHODS: Thirty-one patients with recurrent anterior shoulder dislocation were inspected by arthroscopy, including 23 males and 8 females, with a mean age of 35.1 (18-46) years. The patients were divided into two groups: 17 with shoulder dislocation and hyper-laxity (the hyper-laxity group) and 14 with only traumatic shoulder dislocation (the trauma group). All the patients were assessed by arthroscopy for pathological changes, and the differences in the pathological changes were compared between the two groups. RESULTS: All these 31 patients suffered from anteroinferior labrum injury. Twenty-five had Hill-Sachs injury; 27, bone or cartilage injury of anteroinferior glenoid; 16, SLAP injury; and 5, rotator cuff injury. Bankart injury occurred more in the trauma group, and anterior labroligamentous periosteal sleeve avulsion injury and glenolabral articular disruption injury were more in the hyper-laxity group. Bone or cartilage injury of anteroinferior glenoid was more noticed in the trauma group. CONCLUSIONS: Significant differences are found under arthroscopy in the pathological changes of recurrent anterior shoulder dislocation between the purely traumatic group and the hyper-laxity group. The pathological changes in the trauma group were more severe than in the hyper-laxity group.

Extracellular Vesicles Obtained From Lung Adenocarcinoma Cells Cultured Under Intermittent Hypoxia Induce M2 Macrophage Polarization via miR-20a-5p Delivery.

Conclusion: These findings indicate that EVs obtained from lung adenocarcinoma cells cultured under IH deliver miR-20a-5p to promote M2 macrophage polarization by targeting PTEN.

Impaired Indole Acetic Acid and Reduced Indole-Producing Bacteria Contribute to Swainsonine-Induced Liver Inflammation.

Liver inflammation could be elicited by swainsonine in livestock, affecting the development of agriculture and animal husbandry. Our previous study showed an important role of bile acids (BAs) in swainsonine-induced hepatic inflammation. However, its pathogenesis, particularly the roles of a comprehensive profile of liver and serum metabolites and microbial-derived indole metabolites, has not been clarified. This study aimed to demonstrate the mechanisms linking the indole-producing bacteria and indole metabolites to swainsonine-induced hepatic inflammation by combining Targeted 500 metabolomics and quantitative analysis of indole metabolites. Swainsonine significantly disturbed the liver and serum metabolomes in mice. Genus Akkermansia alleviating inflammation and genus Lactobacillus producing indole metabolites were significantly declined. Indole acetic acid (IAA) was the only reduced aryl hydrocarbon receptor (AHR) ligand in this study. Analogously, some bacteria causing liver damage markedly increased. These findings suggested that indole-producing bacteria and indole metabolites may be potential triggers of swainsonine-induced hepatic inflammation.

New tricks for old drugs- praziquantel ameliorates bleomycin-induced pulmonary fibrosis in mice.

BACKGROUND: Pulmonary fibrosis is a chronic progressive disease with complex pathogenesis, short median survival time, and high mortality. There are few effective drugs approved for pulmonary fibrosis treatment. This study aimed to evaluate the effect of praziquantel (PZQ) on bleomycin (BLM)-induced pulmonary fibrosis. METHODS: In this study, we investigated the role and mechanisms of PZQ in pulmonary fibrosis in a murine model induced by BLM. Parameters investigated included survival rate, lung histopathology, pulmonary collagen deposition, mRNA expression of key genes involved in pulmonary fibrosis pathogenesis, the activity of fibroblast, and M2/M1 macrophage ratio. RESULTS: We found that PZQ improved the survival rate of mice and reduced the body weight loss induced by BLM. Histological examination showed that PZQ significantly inhibited the infiltration of inflammatory cells, collagen deposition, and hydroxyproline content in BLM-induced mice. Besides, PZQ reduced the expression of TGF-ß and MMP-12 in vivo and inhibited the proliferation of fibroblast induced by TGF-ß in vitro. Furthermore, PZQ affected the balance of M2/M1 macrophages. CONCLUSIONS: Our study demonstrated that PZQ could ameliorate BLM-induced pulmonary fibrosis in mice by affecting the balance of M2/M1 macrophages and suppressing the expression of TGF-ß and MMP-12. These findings suggest that PZQ may act as an effective anti-fibrotic agent for preventing the progression of pulmonary fibrosis.

Research on DNA methylation of human osteosarcoma cell MGMT and its relationship with cell resistance to alkylating agents.

The objective of this study was to explore the O(6)-methylguanine-DNA methyltransferase (MGMT) gene methylation status and its protein expression, as well as the effects of demethylating agent 5-Aza-2'-deoxycytidine (5-Aza-CdR) on MGMT gene expression and its resistance to alkylating agents, and to elucidate MGMT expression mechanism and significance in osteosarcoma. The human osteosarcoma cell lines Saos-2 and MG-63 were collected and treated with 5-Aza-CdR for 6 days. The cells not treated with 5-Aza-CdR were set as a negative control. The genomic DNA was extracted from the Saos-2 and MG-63 cells using methylation-specific PCR to detect the promoter CpG island methylation status of the MGMT gene. Cell sensitivity to alkylating agents before and after drug administration was detected by the MTT method. The variation in MGMT gene mRNA and protein was detected by reverse transcription PCR (RT-PCR) and Western blotting. The MGMT promoter gene of normal Saos-2 cells was methylated, with reduced MGMT mRNA and protein expression; the MGMT mRNA and protein expression of Saos-2 cells treated with 5-Aza-CdR was obviously enhanced, and its sensitivity to alkylating agents was reversed. Meanwhile, with promoter CpG island unmethylation of the MGMT gene, MGMT protein was expressed in the normal MG-63 cells and the MG-63 cells treated with 5-Aza-CdR, and both showed resistance to alkylating agents. The methylation status of the MGMT gene promoter in human osteosarcoma cells reflected the cells' ability to induce MGMT protein expression and can be used as a molecular marker to project the sensitivity of cancer tissues to alkylating agent drugs.

The comparison of EPC count and function in the situation of vascular repair at early and late stage.

To investigate the relationship between the changes in the number and function of the late endothelial progenitor cells (EPC) in peripheral blood and the carotid artery stenosis. 60 cases were selected and were divided into the carotid artery stenosis group of 40 cases (mild stenosis in 20 cases, moderate/severe stenosis in 20 cases), normal control group of 20 cases with the global cerebral angiography. Extracted the blood of femoral artery from the patients during the global cerebral angiography, mononuclear cells were isolated from peripheral blood by density-gradient centrifugation and were cultured to 21 days when they were identified as late endothelial progenitor cells, counted the colony numbers of late EPC. Then the proliferation, migration and adherentce ability of late EPC were determined by the MTT assay, modified Boyden and the HFN culturing plates. The amount of the late EPC colonies(34.30 ± 4.90, 25.38 ± 6.33) were significantly reduced in the patients with carotid artery stenosis compared with the control group (46.00 ± 5.64) (P < 0.05); the function of proliferation, migration, adhesion of the late EPC in patiens with cerebral artery stenosis were significantly lower (P < 0.05), the number and function of late EPC decreased with the worsening of vascular stenosis (P < 0.05). The number of EPC in peripheral blood of patients with the carotid artery stenosis decreased, the function was impaired, and number and function changes of late EPC were negatively correlated with the degree of carotid artery stenosis.