A multicenter prospective study of lateral neck lymph node mapping in papillary thyroid cancer.

Background: Despite the high incidence of lateral neck lymph node (LN) metastasis in papillary thyroid cancer (PTC), the management of the lateral neck remains controversial. We aimed to map the draining LNs in the lateral neck using carbon nanoparticles and explore its potential in neck evaluation. Methods: We conducted a multicenter, prospective study in PTC patients who had non-palpable yet suspicious metastatic lateral LNs on ultrasound and/or computed tomography (CT) but could not be confirmed by fine needle aspiration. Carbon nanoparticle suspension was injected peritumorally into the thyroid and modified lateral neck dissection was subsequently performed. Results: A total of 154 patients were enrolled for analysis. And 5,070 lateral LNs were removed, of which 1,079 (21.3%) were dyed. The median of dyed LNs was 6 per case (range, 1-33). The distribution of dyed LNs in neck compartments was IV > III > IIA > IIB/V, independent of tumor size, location, multifocality or microscopic extra-thyroidal extension (ETE). Compared with undyed LNs, the probabilities of metastasis in dyed LNs were significantly increased in compartment III, IV, V, and II-V (III: 29.3% vs. 15.4%, P<0.001; IV: 26.3% vs. 14.5%, P<0.001; V: 16.7% vs. 3.3%, P=0.005; II-V: 26.3% vs. 10.0%, P<0.001). The relative risks of metastasis in dyed LNs compared with undyed LNs were 1.90, 1.82, 5.04 and 2.62 in compartment III, IV, V, and II-V, respectively. Conclusions: It was the first prospective multicenter study to map the lateral neck LNs with carbon nanoparticles, which could help surgeons visualize the suspicious LNs during surgery. Instead of unguided LN biopsy, this method has a potential role in lateral neck assessment for indeterminate lateral LNs in PTC.

A NAC nomogram to predict the probability of three-month unfavorable outcome in Chinese acute ischemic stroke patients treated with mechanical thrombectomy.

BACKGROUND AND PURPOSE: Mechanical thrombectomy (MT) is a standard care for most acute ischemic stroke (AIS) patients. For AIS patients underwent MT, predicting the patients at high risk of unfavorable outcome and adjusting therapeutic strategies accordingly can greatly improve patient outcomes. We aimed to develop and validate a nomogram for individualized prediction of Chinese AIS patients underwent MT. METHODS: We conducted a multicenter prospective study including 238 AIS patients who underwent MT from January 2014 to December 2018. The main outcome measure was three-month unfavorable outcome (modified Rankin Scale 3-6). A nomogram was generated based on multivariate logistic model. We assessed the discriminative performance by using the area under the receiver-operating characteristic curve and calibration of risk prediction model by using the Hosmer-Lemeshow test. RESULTS: In NAC nomogram, NIHSS (National Institutes of Health Stroke Scale) score on admission (OR: 1.193, p < 0.0001), Age (OR: 1.025, p = 0.037) and Creatinine (OR: 1.028, p < 0.0001) remained independent predictors of 3-month unfavorable outcome in Chinese AIS patients treated with MT. The NAC nomogram exhibited an area under the curve of 0.816 for predicting functional impairment. Calibration was good (p = 0.560 for the Hosmer-Lemeshow test). CONCLUSIONS: The NAC nomogram is the first nomogram developed and validated in Chinese AIS patients treated with MT and it may be used to predict 3 months unfavorable outcome for these patients.

Identification and Verification of Biomarker in Clear Cell Renal Cell Carcinoma via Bioinformatics and Neural Network Model.

BACKGROUND: Clear cell renal cell carcinoma (ccRCC) is the most common subtype of kidney cancer, which represents the 9th most frequently diagnosed cancer. However, the molecular mechanism of occurrence and development of ccRCC is indistinct. Therefore, the research aims to identify the hub biomarkers of ccRCC using numerous bioinformatics tools and functional experiments. METHODS: The public data was downloaded from the Gene Expression Omnibus (GEO) database, and the differently expressed genes (DEGs) between ccRCC and normal renal tissues were identified with GEO2R. Protein-protein interaction (PPI) network of the DEGs was constructed, and hub genes were screened with cytoHubba. Then, ten ccRCC tumor samples and ten normal kidney tissues were obtained to verify the expression of hub genes with the RT-qPCR. Finally, the neural network model was constructed to verify the relationship among the genes. RESULTS: A total of 251 DEGs and ten hub genes were identified. AURKB, CCNA2, TPX2, and NCAPG were highly expressed in ccRCC compared with renal tissue. With the increasing expression of AURKB, CCNA2, TPX2, and NCAPG, the pathological stage of ccRCC increased gradually (P < 0.05). Patients with high expression of AURKB, CCNA2, TPX2, and NCAPG have a poor overall survival. After the verification of RT-qPCR, the expression of hub genes was same as the public data. And there were strong correlations between the AURKB, CCNA2, TPX2, and NCAPG with the verification of the neural network model. CONCLUSION: After the identification and verification, AURKB, CCNA2, TPX2, and NCAPG might be related to the occurrence and malignant progression of ccRCC.

MiR-182 promotes cell proliferation by suppressing FBXW7 and FBXW11 in non-small cell lung cancer.

OBJECTIVE: MicroRNAs have been found to be deregulated in lung cancers, which play crucial roles in tumorigenesis and progression. FBXW7 and FBXW11, two important F-box proteins of the ubiquitin-proteasome system (UPS), can target multiple substrates for degradation, in order to regulate cell proliferation and survival in cancers. In the present study, we aimed to explore the potential role and regulating mechanism of miR-182 in non-small cell lung cancer (NSCLC). METHODS: MiRNA expression was evaluated by quantitative reverse-transcription polymerase chain reaction (qRT-PCR). FBXW7, FBXW11, c-Jun, c-Myc and cyclin D protein levels were detected by western blot. Cell growth was determined using cell counting kit (CCK)-8 reagent and colony formation experiment. Then, cell apoptosis and the cell cycle were analyzed on flow cytometry. The target binding activity of miR-182 with FBXW7 or FBXW11 was evaluated through the Dual-Luciferase Reporter Assay System. RESULTS: It was confirmed that miR-182 was significantly upregulated in tumor tissues, compared with adjacent normal tissues, and this was inversely correlated to the protein levels of FBXW7 and FBXW11. The overexpression of miR-182 in NSCLC cells dramatically promoted cell growth, colony formation capacity and cell cycle progression, and inhibited apoptosis in NSCLC cells. In contrast, the downregulation of miR-182 significantly alleviated these properties in vitro. Furthermore, we demonstrated that miR-182 exerted an oncogenic role in NSCLC by directly targeting FBXW7 and FBXW11. CONCLUSION: These results bring new insights into the oncogenic role of miR-182 in NSCLC, indicating that miR-182 might be a novel biomarker for the diagnosis and prognosis of NSCLC.

SOX2-mediated inhibition of miR-223 contributes to STIM1 activation in phenylephrine-induced hypertrophic cardiomyocytes.

Stromal interaction molecule 1 (STIM1) is the key molecule responsible for store-operated Ca2+ entry (SOCE). Numerous studies have demonstrated that STIM1 levels appeared to be enhanced during cardiac hypertrophy. However, the mechanism underlining this process remains to be clarified. In this study, phenylephrine (PE) was employed to establish a model of hypertrophic neonatal rat cardiomyocytes (HNRCs) in vitro, and low expression of primary and mature miR-223 was detected in PE-induced HNRCs. Our results have revealed that downregulation of miR-223 by PE contributed to the increase of STIM1, which in turn induced cardiac hypertrophy. As expected, overexpression of miR-223 could prevent the increase in cell surface and reduce the mRNA levels of ANF and BNP in cardiomyocytes. To address the mechanism triggering downregulation of miR-223 under PE, we demonstrated that PE-induced inhibition of GSK-3ß activity led to the activation of ß-catenin, which initiates the transcription of SOX2. Increased expression of SOX2 occupied the promoter region of primary miR-223 and suppressed its transcription. Therefore, miR-223 appears to be a promising candidate for inhibiting cardiomyocyte hypertrophy, and miR-223/STIM1 axis might be one of interesting targets for the clinical treatment of hypertrophy.

Positive End-Expiratory Pressure Effect of 3 High-Flow Nasal Cannula Devices.

BACKGROUND: High-flow nasal cannula (HFNC) is supposed to provide additional PEEP compared with conventional oxygen therapy. However, the exact determinants of this PEEP effect are unclear. We investigated the factors that might affect the PEEP and compared PEEP performance among 3 HFNC devices. METHODS: Three available HFNC devices were evaluated: the AIRVO 2 device and 2 mechanical ventilators (SV300 and Monnal T75). A device consisting of a test lung (5600i) and an airway model (AMT(IE)) was used to simulate spontaneous breathing. The flows ranged from 0 to their maximum flow with an interval of 10 L/min. The pressures were measured at 4 sites (nasopharynx, supraglottis, carina, and lung) under compliances of 50 and 100 mL/cm H2O and tidal volume of 300, 500, and 700 mL with the mouth closed or open. The influencing factors were determined by multiple linear regression. The sum of squares reduction test was used to compare working curves of PEEP effect among 3 devices. Pairwise comparisons were conducted by using Tukey's multiple comparisons test within an overlap of flow from 0 to 50 L/min. RESULTS: A quadratic curved relationship between PEEP and flow was observed (coefficients were 8.97 × 10-3 for flow and 4.79 × 10-4 for a quadratic element of flow, respectively) but evanished when the mouth was open. The PEEP increased along with lung compliance (coefficient was 2.58 × 10-3). Despite the difference in working curves, both the mechanical ventilators performed slightly better than the AIRVO 2 device at higher flows (40 and 50 L/min). CONCLUSIONS: The mouth status, flow, and compliance were the 3 major influencing factors of PEEP effect, whereas performance of the 2 mechanical ventilators was slightly superior to that of the AIRVO 2 device at higher flows.

Vitamin B6 Prevents Endothelial Dysfunction, Insulin Resistance, and Hepatic Lipid Accumulation in Apoe (-/-) Mice Fed with High-Fat Diet.

Backgrounds. VitB6 deficiency has been associated with a number of adverse health effects. However, the effects of VitB6 in metabolic syndrome are poorly understood. Methods. VitB6 (50 mg/kg/day) was given to Apoe (-/-) mice with hkdigh-fat diet (HFD) for 8 weeks. Endothelial dysfunction, insulin resistance, and hepatic lipid contents were determined. Results. VitB6 administration remarkably increased acetylcholine-induced endothelium-dependent relaxation and decreased random blood glucose level in Apoe (-/-) mice fed with HFD. In addition, VitB6 improved the tolerance of glucose and insulin, normalized the histopathology of liver, and reduced hepatic lipid accumulation but did not affect the liver functions. Clinical and biochemical analysis indicated that the levels of VitB6 were decreased in patients with fatty liver. Conclusions. Vitamin B6 prevents endothelial dysfunction, insulin resistance, and hepatic lipid accumulation in Apoe (-/-) mice fed with HFD. Supplementation of VitB6 should be considered to prevent metabolic syndrome.

Activation of protein kinase C ε enhanced movement ability and paracrine function of rat bone marrow mesenchymal stem cells partly at least independent of SDF-1/CXCR4 axis and PI3K/AKT pathway.

OBJECTS: to probe into the effects of PKCε on migration and paracrine functions of stem cells and potential molecular mechanisms. METHODS: Bone Marrow mesenchymal stem cells (BMMSCs) were obtained from rat femur and passaged. mRNA and protein levels of capital proteins in PKCε signaling, SDF-1/CXCR4 axis and PI3K/AKT pathway in the MSCs in different conditions treating with PKC agonist, specific PKCε inhibitor, CXCR4 antagonist or PI3K inhibitor for 24 hours were analyzed by real-time PCR and western blot, and migration abilities were observed by migration assay in vitro and the changes of paracrine factors in different treatments were analyzed by protein clips assay. RESULTS: the levels of p-JNK, p-P38MAPK, SDF-1, CXCR4, PI3K and p-AKT increased significantly after treating with PKC agonist (P < 0.05) and decreased obviously after treating with specific PKCε inhibitor. Migration ability and paracrine function of MSCs were enhanced in PMA group and attenuated in PKCε inhibitor group, and inhibiting activity of CXCR4 or PI3K attenuated the effects of PKCε, but not abolished completely. CONCLUSION: There was cross-talking between PKCε signaling and SDF-1/CXCR4 axis and PI3K/AKT pathway in signal transduction of MSCs. Activating PKCε could improve migration ability and paracrine function of MSCs partly at least independent of SDF-1/CXCR4 axis and PI3K/AKT pathway.

Relevance of plasma obestatin and early arteriosclerosis in patients with type 2 diabetes mellitus.

We investigated the correlation between obestatin and metabolic parameters and carotid intima-media thickness (IMT) in plasma of patients with type 2 diabetes mellitus (T2DM). We collected 103 patients aged from 60 to 83 years (69.26 ± 5.83 years) form January, 2007 to May, 2009. All patients were divided into normal glucose tolerance (NGT), impaired glucose tolerance (IGT), and T2DM according to the oral glucose tolerance test (OGTT). We found that higher levels of fasting insulin (Fins), fasting blood glucose, 2 h OGTT glucose, homeostasis model assessment of insulin resistance (HOMA-IR), low density lipoprotein cholesterol, glycated haemoglobin, and C-reactive protein (CRP), as well as lower obestatin level and higher intima-media thickness level (IMT), existed in T2DM group compared with NGT group and IGT group (P < 0.01). Also, obestatin level was independently associated with HOMA-IR and CRP, while IMT level was independently associated with HOMA-IR, triglyceride, Fins, and obestatin (P < 0.01), based on stepwise multiple regression analysis. Therefore, we deduced that the low level of plasma obestatin might be related to early arteriosclerosis in patients with T2DM via increasing IMT level, and elevated plasma obestatin levels might protect T2DM patients against carotid atherosclerosis to some extent.

Meta-analysis of outcomes compared between robotic and laparoscopic gastrectomy for gastric cancer.

This meta-analysis was performed to evaluate and compare the outcomes of robotic gastrectomy (RG) and laparoscopic gastrectomy (LG) for treating gastric cancer. A systematic literature search was carried out using the PubMed database, Web of Knowledge, and the Cochrane Library database to obtain comparative studies assessing the safety and efficiency between RG and LG in May, 2013. Data of interest were analyzed by using of Review Manager version 5.2 software (Cochrane Collaboration). A fixed effects model or random effects model was applied according to heterogeneity. Seven papers reporting results that compared robotic gastrectomy with laparoscopic gastrectomy for gastric cancer were selected for this meta-analysis. Our meta- analysis included 2,235 patients with gastric cancer, of which 1,473 had undergone laparoscopic gastrectomy, and 762 had received robotic gastrectomy. Compared with laparoscopic gastrectomy, robotic gastrectomy was associated with longer operative time but less blood loss. There were no significant difference in terms of hospital stay, total postoperative complication rate, proximal margin, distal margin, numbers of harvested lymph nodes and mortality rate between robotic gastrectomy and laparoscopic gastrectomy. Our meta-analysis showed that robotic gastrectomy is a safe technique for treating gastric cancer that compares favorably with laparoscopic gastrectomy in short term outcomes. However, the long term outcomes between the two techniques need to be further examined.

[The effects of cyclooxygenase-2 inhibitors on peritoneal lymphangiogenesis and peritoneal function in uremic rats].

OBJECTIVE: To investigate the effects of cyclooxygenase-2 (COX-2) inhibitor on peritoneal lymphangiogenesis and peritoneum function in uremic rat. METHODS: Uremic rats treated by peritoneal dialysis were intragastric administration celecoxib.Structures of peritoneum, peritoneal function, peritoneal lymphatic vessel density (LVD) were detected in every group. The mRNA of vascular endothelial growth factor-C (VEGF-C), lymphatic vessel endothelial hyaluronan receptor-1(LYVE-1) and COX-2 were tested by RT-PCR. The protein expressions of LYVE-1,VEGF-C, COX-2 were tested by western blot. RESULTS: With the extension of the duration of dialysis, the peritoneum thickness was increasing, inflammatory cell infiltrated obviously, ultrafiltration volume decreased significantly. But the celecoxib could increase ultrafiltration volume and reduce the glucose transport rate (P < 0.05) . Compared with the normal group, the levels of LVD, COX-2,VEGF-C, and LYVE-1 mRNA and protein were significantly up-regulated in uremic and dialysis groups (P < 0.05). Compared with the uremic dialysis group, the levels of LVD, COX-2,VEGF-C and LYVE-1 mRNA and protein were significantly down-regulated in the celecoxib group. There was a positive correlation between COX-2 and VEGF-C, LVD in protein levels, as well as VEGF-C and LVD(all P values<0.05). CONCLUSIONS: Hyper glucose dialysis solution and uremic condition could up-regulate the expression of COX-2,VEGF-C, LYVE-1 in gene and protein level and stimulate lymphangiogenesis. COX-2 inhibitor could delay the change of peritoneal structures and function. COX-2 inhibitor could prevent the lymphangiogenesis in uremic rat treated by peritoneal dialysis, which might down-regulate the expression of VEGF-C by COX-2 depended manner.

[Effect of cisplatin on the expression of Pokemon gene: experiment with different human lung cancer cells].

OBJECTIVE: To investigate the correlation between Pokemon gene and cisplatin mechanism. METHODS: Human lung adenocarcinoma cells of the lines A549 and AGZY83-a, human lung squamous carcinoma cells of the line HE-99, and human giant cell lung cancer cells of the line 95D were cultured and cisplatin was added into the medium. Other lung cancer cells of the above mentioned lines were cultured in the medium without cisplatin and were used as control groups. RT-PCR and Western blotting were used to detect the mRNA and protein expression of Pokemon. RESULTS: Pokemon mRNA and protein were expressed highly in all the 4 cell lines. The Pokemon gene expression did not changed significantly after cisplatin treatment groups. There were not significant differences in the mRNA and protein expression of Pokemon among the 4 experiment groups and the control groups (all P > 0.05). CONCLUSION: Cisplatin has no effect on the Pokemon gene expression of the human lung cancer cells.

Overexpression of Pokemon in non-small cell lung cancer and foreshowing tumor biological behavior as well as clinical results.

BACKGROUND: Transcription factor Pokemon, a central regulation gene of the important tumor suppressor alternative reading frame (ARF), exerted its activity by acting upstream of many tumor-suppressing genes and proto-oncogenes. Its expression in non-small cell lung cancer (NSCLC) and its clinical significance remains unclear. The aim of this study was to investigate the expression of Pokemon in non-small cell lung cancer and to explore its correlation with the clinical pathological characteristics and its influence on patients' prognosis. AIM: Observe the expression of Pokemon in NSCLC and investigate its mechanism and clinical significance. METHODS: Determine the expression of Pokemon in human NSCLC cell lines as well as 55 cases of NSCLC tumor tissues, tumor adjacent tissues and surrounding tissues by reverse transcription-polymerase chain reaction (RT-PCR) and Western blot, and analyze the relationship between Pokemon expression in NSCLC tumor tissues and clinicopathological features. Determine 62 NSCLC tumor tissues (5 years ago) and p14(ARF) expression with immunohistochemical technique, discuss the correlation between them and assess the effect of Pokemon on prognosis of patients with lung cancer. RESULTS: Pokemon mRNA and protein took on high expression in lung cancer cell lines, and the expression difference between cancer tissues, tumor adjacent tissues and surrounding tissues had statistical significance (P<0.05). Pokemon expression and p14(ARF) expression were negatively correlated (r=-0.287). The expression of Pokemon was determined not to be associated with the patient's sex, age, smoking condition, tumor differentiation degree, histology and lymph node metastasis condition. However, its relationship with TNM staging was established (P<0.05). Furthermore, it was shown that the survival rate of patients with negative Pokemon expression was significantly higher than that of those with positive Pokemon expression (P=0.004), therefore, the expression of Pokemon is believed to be an independent factor affecting prognosis (P=0.034). CONCLUSION: There was high expression of Pokemon in NSCLC, Pokemon exerted carcinogenesis by inhibiting ARF and had some clinical significance for prognostic evaluation of the patients with NSCLC.

Expression of transcription factor Pokemon in non-small cell lung cancer and its clinical significance.

BACKGROUND: Transcription factor Pokemon, a central regulation gene of the important tumor suppressor ARF gene, exerted its activity by acting upstream of many tumor-suppressing genes and proto-oncogenes. Its expression in non-small cell lung cancer (NSCLC) and its clinical significance remains unclear. The aim of this study was to investigate the expression of Pokemon in NSCLC and to explore its correlation with the clinical pathological characteristics and its influence on patients' prognosis. METHODS: Fifty-five cases of NSCLC were involved in this study. The expression of Pokemon in the tumor tissue, the corresponding tumor adjacent tissue and the surrounding tissue was detected via reverse transcription-polymerase chain reaction (RT-PCR) and Western blotting, with the aim of investigating the correlation between the expression of Pokemon in tumor tissue of NSCLC and its clinical pathological characteristics. Moreover, a prognostic analysis was carried out based upon the immunohistochemical (IHC) detection of the expression of Pokemon gene in archival tumor specimens (5 years ago) of 62 cases of NSCLC. RESULTS: Statistical significance of the expression of Pokemon mRNA and protein was determined in the tumor tissue, the tumor adjacent tissue and the surrounding tissue (P<0.05). The expression of Pokemon was determined not to be associated with the patients' sex, age, smoking condition, tumor differentiation degree, histology and lymph node metastasis condition. However, its relationship with TNM staging was established (P<0.05). Furthermore, it was shown that the survival rate of patients with negative Pokemon expression was significantly higher than that of those with positive Pokemon expression (P=0.004), therefore, the expression of Pokemon is believed to be an independent factor affecting prognosis (P=0.034). CONCLUSION: Pokemon was over-expressed in NSCLC tissue and the expression of Pokemon might be of clinical significance in non-small cell lung cancer prognostic evaluation.

[Cultivation and nitrogen removal characteristics of ANAMMOX granules].

An SBR reactor seeded with anaerobic granular sludge was started-up to enrich ANAMMOX (anaerobic ammonia oxidation) bacteria and investigate its nitrogen removal characteristics. Research results showed that hydraulic retention time (HRT) was the most important factor to enrich ANAMMOX bacteria. When the HRT was controlled at 30 d during the initial cultivation, the SBR reactor presented ANAMMOX activity at t = 58 days. Simultaneously, the anaerobic granular sludge changed gradually from dust black to brownish color and its diameter became smaller. At t = 90 days, the ANAMMOX was obvious, and ANAMMOX granules was cultivated successfully. NH4(+) -N and NO2(-) -N were removed simultaneously with higher speed and maximum removal rate reached 14.6 g/(m3 x d) and 6.67 g/(m3 x d) respectively. Between t = 110 days and t = 156 days, the nitrogen load was increased gradually to a hydraulic retention time of 5 days. The removal rate of ammonium and nitrite were 60.6% and 62.5% respectively. The ratio of nitrite/ammonium was 1.12. The sludge changed to henna and formed ANAMMOX granulation with high nitrogen removal activity. The total nitrogen load was 34.3 g/(m3 x d).

Inositol-1,4,5-trisphosphate and ryanodine-dependent Ca2+ signaling in a chronic dog model of atrial fibrillation.

Ca2+ signaling regulation plays an important role in triggering and/or maintaining atrial fibrillation (AF). Little is known about the relationship of the inositol-1,4,5-triphosphate receptors (InsP3Rs) and ryanodine receptors (RyRs) in left atrium to chronic AF. In this study, we investigated the expression and function of InsP3R1, InsP3R2 and RyR2 in a chronic dog model of AF. AF was induced in 6 dogs by rapid right atrial pacing for 24 weeks, and a sham procedure was performed in 5 dogs (control group). The intact left atrial myocytes were used to examine the expression and function of InsP3Rs, RyRs by BODIPY(O,R) TR-X ryanodine, heparin-fluorescein conjugate, and were stimulated by caffeine, ATP to release Ca2+ through RyRs, InsP3Rs separately. We also assessed the molecular components of left atrial tissue underlying the amount of RyR2, InsP3R1 and InsP3R2 determined by RT-PCR, immunohistochemistry and Western blot analysis. In the chronic AF group, the Ca2+ released through RyRs is not altered, but the Ca2+ released through InsP3Rs increased significantly. RyR2 distributed in cytosol of myocytes, cellular membrane; its expression significantly decreased in AF group compared to controls. InsP3R1 distributed in cytosol, InsP3R2 distributed not only in cytosol, cellular membrane, but also in nuclear envelope and intercalated discs. The InsP3R1 and InsP3R2 expression significantly increased in chronic AF group compared to controls. These results indicated that in a chronic dog model of AF, the expression and function of RyR2 down-regulated; on the contrary, the expression and function of InsP3R1, InsP3R2 up-regulated, and InsP3R2 may be the major InsP3Rs, which regulate intracellular or even intercellular Ca2+ signal transmission.

[Influence of fluvastatin on left ventricular remodeling after myocardial infarction in rats].

OBJECTIVE: To investigate the effect of long-term administration of fluvastatin on improvement of ventricular remodeling of rats after myocardial infarction and its mechanism. METHODS: Sprague-Dawley rats were subjected to ligation in anterior descending branch of coronary artery and treated with fluvastatin (20 mg.kg(-1) d(-1)) or distilled water for 8 weeks. Doppler echocardiography, hemodynamic study and cardiac histomorphometry were used to estimate the ventricular remodeling and cardiac function. Laser scanning confocal microscope was used to definite the distribution of superoxide anion (O(2)(*-)) and nitrogen monoxide. RT-PCR and immunohistochemistry were used to detect the expression of NOS2 and p22phox in mRNA and protein level. The level of lipid peroxidation, glutathione peroxidase, nitrogen monoxide and total cholesterol were detected too. RESULTS: Administration of fluvastatin ameliorated left ventricular remodeling without affecting the infarct size [(40 +/- 6 vs 42 +/-5)%, P>0.05]. The level of left ventricular end-diastolic pressure [(18.24 +/-6.58 vs 10.74 +/-4.71) mmHg, P<0.05], right ventricular ameliorated relative weight [(0.92 +/-0.19 vs 0.71 +/-0.13) g/kg, P<0.05], the thickness of left ventricular posterior wall [(3.04 +/-0.28 vs 2.60 +/-0.36) mm, P<0.05] decreased after fluvastatin treatment. The left ventricular ejection fraction was not influenced, the relative lung weight and the left atrium diameter reduced [(5.79 +/-2.92 vs 3.69 +/-0.68) g/kg, (0.55 +/-0.12 vs 0.45 +/-0.04) mm, P<0.05]; the expressions of LPO in the plasma and myocardium [(8.64 +/-0.59 vs 7.71 +/-0.66) U/dl, P<0.05; (3.12 +/-0.38 vs 1.93 +/-0.40) ng/microg.pro, P<0.01] were reduced, and the overexpressed NO was inhibited [(436.87 +/-47.22 vs 313.78 +/-34.35) mg/dl, P<0.01], but the expression of GPx increased [(66.13 +/-8.31 vs 79.78 +/-2.38) mg/dl, P<0.01]. The expression of O(2)(*-) and the activity of NADPH oxidase subunit p22phox increased; NOS2 and its products NO were over-expressed too. CONCLUSION: Ventricular remodeling and hemodynamics are improved profoundly in MI rats treated with fluvastatin. The effect of antioxidative stress of fluvastatin might be involved in the mechanism.

Early association of electrocardiogram alteration with infarct size and cardiac function after myocardial infarction.

OBJECTIVE: Myocardial infarction (MI) is the main cause of heart failure, but the relationship between the extent of MI and cardiac function has not been clearly determined. The present study was undertaken to investigate early changes in the electrocardiogram associated with infarct size and cardiac function after MI. METHODS: MI was induced by ligating the left anterior descending coronary artery in rats. Electrocardiograms, echocardiographs and hemodynamic parameters were assessed and myocardial infarct size was measured from mid-transverse sections stained with Masson's trichrome. RESULTS: The sum of pathological Q wave amplitudes was strongly correlated with myocardial infarct size (r = 0.920, P < 0.0001), left ventricular ejection fraction (r = -0.868, P < 0.0001) and left ventricular end diastolic pressure (r = 0.835, P < 0.0004). Furthermore, there was close relationship between MI size and cardiac function as assessed by left ventricular ejection fraction (r = -0.913, P < 0.0001) and left ventricular end diastolic pressure (r = 0.893, P < 0.0001). CONCLUSION: The sum of pathological Q wave amplitudes after MI can be used to estimate the extent of MI as well as cardiac function.