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Abstract The yield and quality of the medicinal plant Achyranthes bidentata can be increased when it is replanted into a field cultivated previously with the same crop, however, fundamental aspects of its biology (so-called “replanting benefit”) still remain to be elucidated. miRNAs are sRNA molecules involved in the post-transcriptional regulation of gene expression in plant biological processes. Here, 267 conserved and 36 novel miRNAs were identified in A. bidentata roots. We compared the miRNA content of the roots (R1) from first-year planting with that of the roots (R2) of second-year replanting, and screened 21 differentially expressed (DE) miRNAs. Based on in silico functional analysis, integrated miRNA-mRNA datasets allowed the identification of 10 miRNA-target family modules, which might participate in the benefit. The expression profiles of the miRNA-target modules were potentially correlated with the presence of the replanting benefit. The indication was that the miRNA-responsive continuous monoculture could reprogram miRNA-mRNA expression patterns, which possibly promote the root growth and development, enhance its transport activity and strengthen its tolerance to various stresses, thereby improving A. bidentata productivity as observed in the replanting benefit. Our study provides basic data for further research on the molecular mechanisms of the benefit in A. bidentata.

Byline: Hai-Long. Li, Raynald. Liu, Xiang-Li. Cui, Song. Lin Sir, Shunt infection is the most common complication associated with ventriculoperitoneal (VP) shunt. Current standard managements for shunt infections include shunt [...]

A letter to then editor is presented regarding two men with shunt infection and was managed by retention of the primary shunt system, intravenous antibiotics administration, and placement of new extraventricular drainage (EVD).

Objective: To study the effects of resveratrol (Res) on pyroptosis of colorectal cancer cells . Methods: ①The experiment of dextran sodium sulfate (DSS) induced colon cancer (CRC) in mice: 30 C57BL/6 mice were randomly divided into control group, Azoxymethane (AOM) group, AOM/DSS group, AOM/DSS+Res group and Res group, with 6 mice in each group, the modeling cycle was 70 days in total. Mice in AOM group, AOM/DSS group and AOM/DSS+Res group, at the first day of the first week, were intraperitoneally injected with AOM (10 mg/kg) once, and the ordinary chaw was replaced with high iron feed, and sterile water was given, 1% DSS water was given to AOM/DSS group and AOM/DSS+Res group. The mice in AOM/DSS+Res and Res groups were given resveratrol (50 mg/kg) by oral gavage, When the mold was finished, colon tissue of mice was fixed, embedded and sectionalized. The expressions of NLRP3, Caspase-1 and IL-18 in colon tissues of mice were detected by IHC and Western blot. ②In vitro experiment: HCT 116 cells were given Res (2.4 μg/L) and transfected with miR-31. The Res was divided into 4 groups and labeled with 0 h, 12 h, 24 h and 48 h respectively. The transfected cells were divided into 5 groups: Control group, miR-31 mimic group, miR-31 mimic + Res group, miR-31 inhibitor group, miR-31 inhibitor + Res group. The protein expressions of NLRP3, Caspase-1, GSDMD-N, IL-18 and IL-1β were detected by Western blot. Results: Animal experiments: Compared with control group, the protein expressions of NLRP3, Caspase-1 and IL-18 in AOM/DSS group were increased significantly (P<0.01). The protein expression levels of NLRP3, Caspase-1 and IL-18 in AOM/DSS+Res group were significantly lower than those in AOM/DSS group (P<0.01). Cell experiments: Compared with the control group, the protein expressions of NLRP3 (P<0.01), GSDMD-N (P<0.05) and IL-18 (P< 0.01) in miR-31 mimic group were increased significantly. The protein expressions of NLRP3, GSDMD-N and IL-18 in miR-31 inhibitor group were decreased significantly (P<0.05). Conclusion: Res inhibited the pyroptosis of colorectal cancer cells through pyroptosis.

Objective: To investigate the effects of miR-31 on TLR4/NF-κB signaling pathway and apoptosis-related proteins in dextran sulfate sodium (DSS) induced mouse colon colitis. Methods: ① Mouse model of colon colitis: 1% DSS was used to induce mouse ulcerative colitis (UC). Fourteen FVB non-transgenic mice were randomly divided into control group (n= 6), DSS group (n= 8), and 16 FVB miR-31 transgenic mice were randomly divided into miR-31 overexpression group (n= 8), miR-31 overexpression +DSS group (n= 8). DSS was dissolved in water and administered to mice by drinking water. The DSS group and miR-31+DSS group drank 1% DSS water in the first week, normal sterilized water in the second week, and 1% DSS water in the third week, after 5 weeks, the modeling was completed, then the colon tissues of the mice were collected. Western blot and IHC were used to detect the expressions of NF-κB p65, TLR4, Bax and Bcl-2 proteins in mouse colon tissue, TUNEL was used to detect apoptosis of mouse colon tissues. ② Cell culture experiments: Transfection of miR-31mimic and inhibitor by lipofectamine resulted in overexpression or knockdown of miR-31 in human colon epithelial cell line HCT 116 cells, each group was repeated three times and cells were collected 48 h later, Western blot was used to detect the expressions of NF-κB p65 and TLR4 protein. Results: ① In animal experiments, compared with the control group, the expression levels of NF-κB p65, TLR4 protein and apoptotic cell index in the DSS group and miR-31 overexpression group in mouse colon tissue were significantly increased (P＜0.05 or P＜0.01), and the Bcl-2 / Bax ratio was significantly reduced (P＜0.05 or P＜0.01); and compared with the DSS group, the expression levels of NF-κB p65, TLR4 protein and apoptotic cell index in the miR-31+DSS group were significantly increased (P＜0.01), while the Bcl-2/Bax ratio was significantly decreased (P＜0.01). ② In cell experiments, compared with the control group, the expression levels of NF-κB p65 and TLR4 protein in the over-expressed miR-31 group of HCT 116 cells were significantly increased (P＜0.05 or P＜0.01), the expressions of NF-κB p65 and TLR4 protein in miR-31 knockdown group were decreased (P＜0.05). Conclusion: miR-31 promotes the development of colitis by promoting TLR4/NF-κB signaling pathway and mediating apoptosis of intestinal epithelial cells.

Objective: To investigate the protective effects of nitidine chloride (NC) on dextran sodium sulfate (DSS) - induced ulcerative colitis (UC) in mice by targeting miR-31 and its underlying mechanisms., Methods: DSS at the concentration of 1% was used to induce UC in mice. Thirty C57BL/6 male mice were randomly divided into four groups: normal control group (n=7), DSS group (n=8), DSS + NC group (7.27 mg/kg) (n=8) and NC group (n=7). DSS was added in drinking water, and NC was administrated by gavage. The period of modeling lasted for 3 weeks. The control group and NC group drank sterile water every day, DSS group and DSS + NC group drank 1% DSS water in the first week, normal water in the second week and 1% DSS water in the third week. In the last week of modeling, mice in control group and DSS group were given 0.5% CMC-Na by gavage, while mice in DSS + NC group and NC group were given NC by gavage. After the establishment of the model, the disease activity index (DAI) related to colitis was observed, the pathological score of colon tissue was evaluated by HE staining, the expression level of miR-31 in colon tissue was detected by qPCR, and the protein expressions of NF -κ B and COX-2 in colon tissue were detected by Western blot., Results: ① Compared with DSS group, the DAI in the DSS + NC group was decreased (P＜0.01). The colonic pathological injury was obviously ameliorated after treated by NC. ② Compared with normal control group, the expression of miR-31 in colonic tissue of DSS group was increased significantly(P＜0.01), compared with DSS group, the expression of miR-31 was decreased after treatment with NC(P＜ 0.05). ③ Compared with DSS group, the levels of inflammatory protein NF-κB and COX-2 in DSS + NC group was decreased significantly (P＜0.05)., Conclusion: Nitidine chloride has obvious therapeutic effects on DSS induced mouse colitis, and its anti-inflammatory mechanism is related to the down-regulation of miR-31 expression.

Objective: To investigate the anti-ulcerative colitis mechanism of resveratrol through regulation of Wnt/β-catenin signaling pathway., Methods: ①The experiment of ulcerative colitis induced by dextran sulfate sodium salt (DSS): 28 C57BL/6 mice were randomly divided into four groups including control group(n=7), DSS group(n=7), DSS+Resveratrol (DSS+Res) group(n=7) and Res group(n=7). The experiment lasted for 3 weeks. Ulcerative colitis of mice was induced by drinking DSS water and treated with resveratrol by intragastric administration. The mice were weighed daily and their activities and state of feces were recorded. After that, the mice were euthanized, the spleens were weighed, and the colonic length was measured.Hematoxylin-eosin staining (HE) was used to observe the pathological changes of the colon, and the expression of miR-31 in colonic tissue was detected by quantitative real-time PCR (qPCR). The expressions of β-catenin and Cyclin D1 were measured by Western blot. ②In vitro experiment: HCT 116 cells were treated with resveratrol at 10 mg/ml, the expressions of β-catenin, LDL receptor related protein-6 (LRP-6), frizzled-3 (FZD3) and c-Myc were detected. The expression of β-catenin was also detected in HCT 116 cells transfected with miRNA-31 mimic and miRNA-31 inhibitor., Results: ① The body weight was decreased in DSS group, the activity was decreased and blood stool appeared. The colonic length of mice was shortened, the spleen was enlarged and the tissue was damaged seriously in DSS group. While the above symptoms were improved after resveratrol treatment. ② Resveratrol inhibited the expressions of miRNA-31, β-catenin and CyclinD1 in ulcerative colitis mice, and also down-regulated the expressions of β-catenin, LRP-6, FZD3 and c-Myc in HCT 116 cells. After transfection of miRNA-31 inhibitor, the expression of β-catenin was decreased in HCT 116 cells., Conclusion: Resveratrol suppresses DSS induced colitis by down-regulation of Wnt signal pathway. The down-regulation of Wnt signal may be related to miRNA-31.

Objective: To investigate the protective effects and the possible mechanisms of simvastatin on myocardial injury induced by diabetes., Methods: Twenty-four SD rats (180~220)g were randomly divided into control group (control, n =8) and modeled groups( n =16), the modeled groups were injected with streptozotocin intraperitoneally to induce diabetes. Then the modeled rats were randomly divided into diabetes mellitus group (DM group, n =8) and diabetes mellitus + simvastatin group (DM+S group, n =8). Rats in DM+S group were treated with simvastatin at the dose of 40 mg/(kg·d)by gavage for 4 weeks, and the other two groups were treated with the same amount of saline. At the end of experiments, the heart tissues were collected for further observation. The content of malondialdehyde (MDA) and the activity of superoxide dismutase (SOD) in heart tissues were measured by spectrophotometry; HE staining of rat heart slides was used to observe the pathological changes; TUNEL assay was used to determine the apoptosis index of myocardial cells in each groups; The distribution of p53 in the heart tissues was evaluated by immunohistochemistry; Western blot was used to detect the expressions of p53, p53-phospho-serine 15, Bax and Bcl-2 in the heart tissues., Results: ①Compared with control group, the content of malondialdehyde (MDA) was increased while the activity of superoxide dismutase (SOD) was decreased significantly in DM group ( P <0.01). After simvastatin administration, the activity of SOD was increased and the content of MDA was decreased significantly ( P <0.01). ② HE staining results showed that the myocardial cells in the DM group were disorganized, with unclear morphological structure and a large number of inflammatory cells infiltration. Compared with DM group, the myocardial morphology in DM+S group was improved significantly. ③TUNEL staining results showed that the apoptosis index of myocardial cells in DM group was increased significantly compared with that of control group, and the apoptosis index was decreased significantly after the treatment of simvastatin ( P <0.01).④ Immunohistochemistry showed that compared with control group,the expression of p53 in DM group was increased significantly, and was expressed in both cytoplasm and nucleus, while the expression of p53 in DM+S group was decreased and the expression of p53 in nucleus was decreased significantly ( P <0.01). ⑤ The results of Western blot showed that the expression levels of p53, p53-phospho-serine15 and Bax were higher than those in control group, and the expression of Bcl-2 was lower than that in control group ( P <0.01). After simvastatin administration, the expression levels of p53,p53-phospho-serine 15 ( P <0.01) and Bax were decreased significantly ( P <0.05) and the expression of Bcl-2 was increased ( P <0.05)., Conclusions: Simvastatin exerted protective effects on myocardial injury caused by diabetes through improving the abnormal morphological changes of diabetic myocardium, alleviating oxidative stress and inhibiting apoptosis of myocardial cells. The mechanism is related to the regulation of apoptosis pathway mediated by p53.

Objective: To observe the protective effect of simvastatin on renal injury in diabetic rats and to explore the possible molecular mechanism., Methods: Twenty-four SD rats were randomly divided into normal control (NC) group ( n =8) and modeling group ( n =16).The rats in modeling group were injected with streptozotocin intraperitoneally at a dose of 55 mg/kg to establishing diabetic rat model. After diabetic ratmodel established successfully, the diabetic rats were randomly subdivided into diabetes mellitus (DM) group and diabetes mellitus + simvastatin (DM+Sim) group ( n =8).Rats in DM+Sim group were given simvastatin at a dose of 40 mg/kg by oral gavages, once a day for 4 weeks. Morphological changes and interstitial fibrosis of kidney were observed by histopathological method. The expressions of relative protein in endoplasmic reticulum stress, inflammatory molecules in renal tissues and cells apoptosis were detected by molecular biology method., Results: ① Compared with NC group, the pathological changes of glomerulus and tubulointerstitium were obvious, and the collagen fibers were obviously erythrophilous and unevenly distributed in DM group. Compared with DM group, the morphological changes and fibrosis were significantly improved in DM+Sim group. ② The expressions of GRP78, p-IRE1α, NF-κB p65 and MCP-1 in DM group were significantly higher than those in NC group ( P <0.05), while the expressions of GRP78, p-IRE1α, NF-κB p65 and MCP-1in DM + Sim group were decreased ( P <0.05). ③ There were a small number of apoptotic nuclei in the glomeruli and adjunctive renal tubules in NC group detected by TUNEL assay, while there were a large number of apoptotic nuclei in DM group ( P <0.01). The number of apoptotic nuclei was decreased significantly in DM+Sim group ( P <0.01)., Conclusions: Morphologicalchanges and fibrosis of renal tissue are improved obviously, and the number of apoptotic cells is decreased significantly after administration of simvastatin in diabetic rats. Simvastatin exertsthe protective effect on diabetic nephropathy by inhibiting endoplasmic reticulum stress and NF-κB inflammatory signaling pathway, and reducing renal cell apoptosis.

Objective: To investigate the effects of β3-adrenoceptors(β3-AR) inhibitor SR 59230A on MicroRNAs expression in rat myocardium with chronic heart failure and the related mechanisms., Methods: One hundred male SD rats were randomly divided into sham operated group(40)and chronic heart failure(CHF)group(60). Coronary artery ligation was used to induce CHF. Then the rats in CHF group were further randomly divided into CHF control group and CHF+SR 59230A group (CHF+SR). Rats in the sham group were divided into sham control group and sham+SR 59230A group (Sham+SR). The rats in Sham+SR group and CHF+SR group were treated with 1 ml SR 59230A(85 mmoL/L in 0.9% saline)twice a day for seven weeks by intraperitoneal injection, while the rats in control groups were injected with the same amount of saline for seven weeks separately. miScript miRNA PCR Arrays were used to determine the expression profile of MicroRNAs. Immunohistochemistry was used to evaluate the distribution of the related proteins in the heart tissue sections. Western blot was used to detect the expressions of nuclear factor-kappaB(NF-κB),p53 and p53-Phospho-Serine 15 in the heart., Results: ①After in vivo blockade of β3-AR by SR 59230A, there were 18MicroRNAs down-regulated in sham control group and CHF control group. Within them, 6 MicroRNAs were related to NF-κB signaling pathway, they were miR-125b-5p,miR-143-3p,miR-145-5p,miR-26a-5p,miR-30a-5p and miR-320-5p. ②Slides from the heart tissue showed that NF-κB was distributed both in nucleus and cytoplasm, while p53 in cytoplasm was more than that in nucleus in heart tissue sections. The expressions of NF-κB and p53 were higher in the CHF control group than those in the sham control group( P <0.05), but were lower in CHF+SR group than those in CHF control group( P <0.05),while they were elevated in Sham+SR group compared to the sham control group( P <0.05). ③ Compared with the sham control group, the protein expression of NF-κB p65 was increased significantly in the CHF control group ( P <0.05). After treated with SR59230A in vivo ,the protein expressions of NF-κB and p53-Phospho-Serine 15 were decreased significantly in CHF rats( P <0.05),while the protein expressions of NF-κB, p53 and p53-Phospho-Serine 15 proteins were increased in the sham rats ( P <0.05)., Conclusions: Blocking of β3-AR improved the damaged heart in CHF rats; β3-AR caused the change of MicroRNAs expression, and it related to NF-κB signal pathway.

Objective: To explore whether targeting phosphoglycerate kinase 1 (PGK1) can enhance the sensitivity of BRAF V600E mutation melanoma cells to vemurafenib., Methods: The methods of cell biology, molecular biology and pharmacology(MTT assay, Western blot, FCM, Colongenic assay) were used in this study., Results: ① Silencing of PGK1 expression increased the efficacy of vemurafenib in melanoma cells, as evidenced by greater killing in the tumor cells subjected to combined treatment of vemurafenib with siPGK1; ②The mechanism of enhanced sensitivity of melanoma cells to vemurafenib was associated with activation of apoptotic signaling pathway., Conclusions: Targeting of PGK1 may represent a novel strategy of sensitizing melanoma cells to vemurafinib.

Objective: To explore the effects of SR59230A on the tension and microRNA (miRNA) expression of rat thoracic aorta., Methods: Forty-four SD rats were used in the experiment. Twenty-four rats were used to observe the effect of SR on the tension of thoracic aortic rings. Another 20 rats were randomly divided into control ( n =10) and SR group( n =10). Rats in SR group were injected SR intraperitoneally,and in control group were given 0.9% of saline. After 5 weeks, the blood pressure of all rats were measured. Then the tension to NA and the expression of miRNA of thoracic aorta rings were measured., Results: (1) The tension of thoracic aortic rings responding to 30 mmol/LKCl were increased by pretreatment of SR ( P <0.05); (2) After 5 weeks injection of SR, systolic pressure was increased ( P <0.05); (3) The tension in SR group was increased in presence of 1 μ mol/L and 10 μ mol/L of NA ( P <0.05, P <0.01). (4) After 5 weeks of SR in vivo application,18 miRNA were down-regulated, 7 of them had statistical significance, they were rno-miR-143-3p, rno-miR-29b-3p, rno-miR-31a-5p, rno-let-7b-5p, rno-miR-214-3p, rno-miR-222-3p and rno-miR-352; 11 miRNA were up-regulated, 4 of them had statistical significance, they were rno-miR-206-3p、rno-miR-223-3p、rno-miR-342-3p and rno-miR-499-5p respectively., Conclusions: SR59230A increased the tension of rat thoracic aorta. In vivo administration of SR led to increase of systolic pressure of rat,down-regulation of rno-miR-143-3p、rno-miR-29b-3p、rno-miR-31a-5p、rno-let-7b-5p、rno-miR-214-3p、rno-miR-222-3p、rno-miR-352 and up-regulation of rno-miR-206-3p、rno-miR-223-3p、rno-miR-342-3p and rno-miR-499-5p.

Objective: To observe the effect of β₃adrenoceptors (β₃-AR) activation on rat thoracic aorta smooth muscle contractility and the possible related mechanism., Methods: The endothelium removed thoracic aorta was pre-contracted with 30 mmol/L KCl physiological saline solution (PSS). Then the tension of the thoracic aorta was recorded in presence of BRL37344 (BRL) to determine the action of β₃-AR. The tension of the thoracic aorta was also recorded in the presence of Propranolol (PRA), SR59230A (SR), L-NNA, H-89 and Iberiotoxin (IBTX) respectively to reveal the underling mechanism of β₃-AR activation on rat vascular smooth muscle. Immunohistochemistry was adopted to confirm the existence and the distribution of β₃-AR in rat thoracic aorta., Results: The results showed that: (1) The thoracic aorta was relaxed by β₃-AR activation, with a relaxation percentage of (10.59 ± 0.79). (2) β₃-AR was expressed in both endothelial and smooth muscle layer in thoracic aorta sections of rats. (3) PRA did not block the effect of BRL on the thoracic aorta. The relaxation actions of BRL could be antagonized by pre-incubating the thoracic aorta with SR. (4) L-NNA (a NOS inhibitor) and H-89 (a PKA inhibitor) reversed the relaxation effect of BRL on vascular smooth muscle. (5) The effect of BRL was decreased after application of Ibriotoxin (IBTX), a large conductance calcium dependent potassium channel blocker., Conclusion: The results confirmed that activation of β₃-AR led to relaxation of thoracic aorta smooth muscle. The relaxation action of β₃-AR on smooth muscle of rat thoracic aorta was related to activation of NOS and PKA signaling pathway. Large conductance Ca²⁺-K⁺ channels were involved in the relaxation action of β₃-AR activation on rat thoracic aorta smooth muscle.

Objective: To analyze the features of isocitrate dehydrogenase 1 (IDH 1) mutation in 165 oligodendroglial tumors., Methods: IDH1 was detected in a series of 165 oligodendroglial paraffin specimens from 2009 to 2011. And their features were analyzed., Results: Mutant IDH1 was detected in 111 (67.3%) tumors including 109 (98.2%) CGT→CAT mutations, 1 (0.9%) CGT→AGT mutation and 1 (0.9%) CGT→TGT mutation. The frequencies of IDH mutation in AO, O and OA were 13/15, 83.3% and 72.9% respectively. They were significantly higher than that in AOA (27.0%, P < 0.001)., Conclusion: The different frequencies of IDH1 mutation in different subsets of oligodendroglial tumors may imply varied tumorigenic pathways between subsets.

Considering that α-1 repeat region may be involved in the ion binding and translocation of Na(+)-Ca(2+) exchanger (NCX), it is possible that the antibodies against NCX α-1 repeat may have a crucial action on NCX activity. The aim of the present study is to investigate the effect of antibody against α-1 repeat (117-137), designated as α-1(117-137), on NCX activity. The antibody against the synthesized α-1(117-137) was prepared and affinity-purified. Whole-cell patch clamp technique was used to study the change of Na(+)-Ca(2+) exchange current (I(Na/Ca)) in adult rat cardiomyocytes. To evaluate the functional specificity of this antibody, its effects on L-type Ca(2+) current (I(Ca,L)), voltage-gated Na(+) current (I(Na)) and delayed rectifier K(+) current (I(K)) were also observed. The amino acid sequences of α-1(117-137) in NCX and residues 1 076-1 096 within L-type Ca(2+) channel were compared using EMBOSS Pairwise Alignment Algorithms. The results showed that outward and inward I(Na/Ca) were decreased by the antibody against α-1(117-137) dose-dependently in the concentration range from 10 to 160 nmol/L, with IC(50) values of 18.9 nmol/L and 22.4 nmol/L, respectively. Meanwhile, the antibody also decreased I(Ca,L) in a concentration-dependent manner with IC(50) of 22.7 nmol/L. No obvious effects of the antibody on I(Na) and I(K) were observed. Moreover, comparison of the amino acid sequences showed there was 23.8% sequence similarity between NCX α-1(117-137) and residues 1 076-1 096 within L-type Ca(2+) channel. These results suggest that antibody against α-1(117-137) is a blocking antibody to NCX and can also decrease I(Ca,L) in a concentration-dependent manner, while it does not have obvious effects on I(Na) and I(K).

Objective: To investigate the frequencies of combining loss of heterozygosity (LOH) of chromosome 1p/19q in gliomas of different pathologies and analyze the clinical factors correlated with combining LOH by logistic regression., Methods: Tumor samples from 127 glioma patients were collected. The status of 1p and 19q was evaluated by fluorescence in situ hybridization (FISH) and the frequencies of combining 1p/19q LOH in gliomas of different pathologies were analyzed., Results: The frequencies of combining 1p/19q LOH in astrocytic, oligoastrocytic and oligodendroglial tumors were 19.30%, 50.00% and 80.77% respectively. The frequencies of combining 1p/19q LOH in oligoastrocytic and oligodendroglial tumors were higher than those in astrocytic tumors (P < 0.01) and the frequencies of combining 1p/19q LOH in oligodendroglial tumors was higher than those in oligoastrocytic tumors (P < 0.05). The frequencies of 1p/19q LOH in astrocytic, oligoastrocytic and oligodendroglial tumors were 12.28%, 11.36 and 0 respectively. There was no significant correlation between combining 1p/19q LOH and age, gender and grade by logistic regression., Conclusion: In gliomas, combining 1p/19q LOH is proved to be the most common pattern of chromosome deletion involving 1p or 19q. It is significantly correlated with oligodendroglial component. Combining 1p/19q LOH may be valuable in the diagnosis, treatment and prognostic prediction for glioma with oligodendroglial component.

Objectives: To find possible factors correlated with combined loss of heterozygosity (LOH) of 1p and 19q., Methods: The status of 1p and 19q of 138 glioma specimen from January 2009 to December 2009 was evaluated by Fluorescence in situ hybridization (FISH) method, and the frequencies of combining LOH of 1p/19q were compared between different pathologies, brain sub-regions, genders and ages., Results: The frequencies of combined LOH of 1p and 19q of oligodendroglial (81.3%) and oligo astrocytic tumors (55.8%) were significantly higher than that of astrocytic tumor (22.2%) (P < 0.01), and the frequency of oligodendroglial tumor was significantly higher than that of oligo astrocytic tumor (P < 0.05). The frequency of combining LOH of 1p and 19q in frontal lobe (61.8%) was higher than that in temporal (31.8%) and insular lobes (34.6%) (P < 0.05)., Conclusion: Combining LOH of 1p and 19q has significant correlation with the pathologies and brain sub-regions.

The present study was aimed to investigate the positive inotropic mechanism of carbachol (CCh) on rat ventricular myocytes. The effects of CCh on L-type calcium current (I(Ca,L)) and Na(+)/Ca(2+) exchange current (I(Na/Ca)) were investigated in isolated rat ventricular myocytes. After loading myocytes with Fura-2/AM, electrically triggered Ca(2+) transient and cell shortening in single myocyte were measured simultaneously using ion imaging system with charge-coupled device (CCD) camera. CCh (100 mumol/L) increased I(Na/Ca) in forward mode from (1.18 +/- 0.57) pA/pF in the control group to (1.65 +/- 0.52) pA/pF (P<0.01) and that in reverse mode from (1.11 +/- 0.49) pA/pF in the control group to (1.53 +/- 0.52) pA/pF (P<0.01), respectively. CCh had no effect on I(Ca,L). The stimulatory effect of CCh on I(Na/Ca) was blocked by application of atropine, a non-selective M muscarinic receptor antagonist, and methoctramine, a selective M(2) muscarinic receptor antagonist. CCh (100 mumol/L) increased cell shortening from (3.00 +/- 0.67) mum in the control group to (3.55 +/- 1.21) mum. Ca(2+) transient was also increased from 203.8 +/- 50.0 in the control group to 234.8 +/- 64.3 in 100 mumol/L CCh group. KB-R7943, a selective inhibitor of reverse mode Na(+)/Ca(2+) exchange, did not change the baseline level of cell shortening and Ca(2+) transient, while completely abolished CCh-induced increments of both Ca(2+) transient and cell shortening. CCh increased cell shortening and Ca(2+) transient in the presence of nicardipine, indicating that the positive inotropic effect of CCh was through activation of Na(+)/Ca(2+) exchange. Calcium sensitivity was not changed by CCh. Both atropine and methoctramine abolished the positive inotropic effects of CCh, demonstrating that CCh induced positive inotropism via the M(2) muscarinic receptor. The results suggest that CCh increases cell contraction and Ca(2+) transient in rat ventricular myocytes. This positive inotropic effect of CCh is through activation of reverse mode Na(+)/Ca(2+) exchange, and M(2) receptors are involved in mediating CCh-induced contraction.

Neuropeptide Y (NPY) co-exists with norepinephrine (NE) in sympathetic terminals, and is the most abundant neuropeptide in myocardium. Many studies have focused on the effects of NE on ion channels in cardiac myocytes and its physiological significance has been elucidated relatively profoundly. There have been few investigations, however, on the physiological significance of NPY in myocardium. The effects of NPY on L-type Ca2+ channel currents (I(Ca-L)) were evaluated in some studies and different results were presented, which might be attributed to the different species of animal tested and different methods used. It is necessary, therefore, to study the effects of NPY on ion channels in cardiac myocytes systematically and further to discuss the biological significance of their coexistence with NE in sympathetic terminals. The single ventricular myocytes from adult rat or guinea pig (only for measuring I(K)) were prepared using enzymatic dispersion. I(Ca-L), I(to), I(Na/Ca), I(Na) and I(K) in the cellular membrane were observed using whole cell voltage-clamp recording. In the present study, NPY from 1.0 to 100 nmol/L dose-dependently inhibited I(Ca-L) (P<0.01, n=5). The maximal rate of inhibition in this study reached 39% and IC(50) was 1.86 nmol/L. NPY had no effect on the voltage-dependence of calcium current amplitude and on the voltage-dependence of the steady-state gating variables. I(Ca-L) was activated at -30 mV, reaching the maximum at 0 mV. When both NE and NPY were applied with a concentration ratio of 500:1, 10 nmol/L NPY inhibited I(Ca-L) that had been increased by 5 mumol/L NE, which was consistent with the effect of NPY only on I(Ca-L). NPY also inhibited I(Na/Ca). At a concentration of 10 nmol/L, NPY inhibited inward and outward I(Na/Ca) from (0.27+/-0.11) pA/pF and (0.45+/-0.12) pA/pF to (0.06+/-0.01) pA/pF and (0.27+/-0.09) pA/pF, respectively (P<0.05, n=4). NPY at 10 nmol/L increased I(to) from (12.5+/-0.70) pA/pF to (14.7+/-0.59) pA/pF(P<0.05, n=4). NPY at 10 nmol/L did not affect I(Na) in rat myocytes and I(K) in guinea pig myocytes. NPY increased the speed of action potential depolarization and reduced action potential duration of I(Ca-L), I(Na/Ca) and I(to), which contributed to the reduction of contraction. These results indicate that the effects of NPY are opposite to the effects of NE on ion channels of cardiac myocytes.

Stimulation of cardiac mAChRs by carbachol (CCh) produces a biphasic inotropic response. The mechanisms of the positive inotropic response by higher concentration of CCh appear to be paradoxical. This article was aimed to study the mechanism of the positive inotropic effect of CCh in guinea pig ventricular myocytes. The effects of CCh on L-type calcium current (I(Ca)) and Na/Ca exchange current (I(Na/Ca)) were observed in voltage-clamped guinea pig ventricular myocytes by using Axon 200A amplifier. The results showed that CCh (100 micromol/L) increased both forward mode and reverse mode I(Na/Ca) from (1.2+/-0.1) pA/pF to (2.0+/-0.3) pA/pF for forward mode (P<0.01) and from (1.3+/-0.5) pA/pF to (2.1+/-0.8) pA/pF for reverse mode (P<0.01), respectively. CCh had no effect on I(Ca). The stimulating effect of CCh on I(Na/Ca) could be blocked by application of atropine, a nonselective blocker of muscarinic receptors, which means that the stimulating effect of CCh is through the activation of muscarinic receptors. We made a further study by using methoctramine, a selective antagonist of M2 muscarinic receptors. It completely abolished I(Na/Ca) induced by 100 micromol/L CCh, indicating that the effect of CCh on I(Na/Ca) was mediated by M2 muscarinic receptors. It is generally accepted that contraction in cardiac myocytes results from elevation of intracellular Ca2+ concentration. Ca2+ enters the cells through two pathways: L-type Ca2+ channels and, less importantly, reverse mode Na/Ca exchange. The calcium influx via both pathways promotes the contraction of cardiac myocytes. Because CCh had no effect on L-type Ca2+ current, the increase in Na/Ca exchange current might be the main factor in the positive inotropism of CCh. These results suggest that the positive inotropic effect of CCh in guinea pig heart is through stimulation of Na/Ca exchange and is mediated by M2 muscarinic receptors.

To study the inotropic effect of enhanced Na(+)-Ca(2+) exchange in the rat papillary muscles and isolated heart, the developed tension in the rat papillary muscles was measured and the left ventricular functions were assessed in the isolated rat heart. E-4031, a selective activator for Na(+)-Ca(2+) exchange in rats, concentration-dependently increased the developed contractile tension in the rat papillary muscles (P<0.05, n=6) and the left ventricular functions in the isolated heart; KB-R7943, a selective Na(+)-Ca(2+) exchange inhibitor, exhibited opposite effect. A combination of 0.5 micromol/L ouabain and 3.0 micromol/L E-4031 resulted in a potentiation of the developed contractile tension of the rat papillary muscles from 0.25+/-0.03 g to 0.29+/-0.04 g. The combination also enhanced the augmentation of the left ventricular functions induced by ouabain. These results indicate that E-4031 exerts a positive inotropic effect on the rat papillary muscles and isolated heart via increasing the activity of Na(+)-Ca(2+) exchange, and potentiates the positive inotropic effects of ouabain.

Calcium sensitizers exert positive inotropic effects without increasing intracellular Ca(2+). Thus, they avoid the undesired effects of Ca(2+) overload such as arrhythmias and cell injury, but most of them may impair myocyte relaxation. However, MCI-154, also a calcium sensitizer, has no impairment to cardiomyocyte relaxation. To clarify the underlying mechanisms, we examined the effects of MCI-154 on Ca(2+) transient and cell contraction using ion imaging system, and its influence on L-type Ca(2+) current and Na(+)/ Ca(2+) exchange current with patch clamp technique in rat ventricular myocytes as well. The results showed that: (1) MCI-154 (1-100 micromol/L) had no effect on L-type Ca(2+) current; (2) MCI-154 concentration-dependently increased cell shortening from 5.00+/-1.6 microm of control to 6.2+/-1.6 microm at 1 micromol/L, 8.7+/-1.6 microm at 10 micromol/L and 14.0+/-1.4 microm at 100 micromol/L, respectively, with a slight increase in Ca(2+) transient amplitude and an abbreviation of Ca(2+) transient restore kinetics assessed by time to 50% restore (TR(50)) and time to 90% restore (TR(90)); (3) MCI-154 dose-dependently increased the electrogenic Na(+)/ Ca(2+) exchange current both in the inward and the outward directions in rat ventricular myocytes. These results indicate that MCI-154 exerted a positive inotropic action without impairing myocyte relaxation. The stimulation of inward Na(+)/ Ca(2+) exchange current may accelerate the Ca(2+) efflux, leading to abbreviations of TR(50) and TR(90) in rat myocytes. The findings suggest that the improvement by MCI-154 of myocyte relaxation is attributed to the forward mode of Na(+)/ Ca(2+) exchange.

Aim: To study the effects of N-[4-[[1-[2-(6-methyl-2-pyridinyl)ethyl]-4-piperidinyl]carbonyl]phenyl]methanesulfonamide dihydrochloride dihydrate (E-4031), a specific Ik blocker, on Ca2+ transient and cell contraction of normal and hypertrophied rat ventricular myocytes., Methods: Electrically triggered Ca2+ transient and cell shortening were measured simultaneously using the Ion Imaging System with charge coupled digital (CCD) camera., Results: E-4031 (10 micromol/L) increased Ca2+ transient and cell shortening from (210+/-49) and (3.0+/-0.8) micron to (245+/-47) and (3.6+/-1.0) micron, respectively (P<0.05) in normal cardiomyocytes and from (196+/-54) and (3.0+/-1.3) micron to (240+/-49) and (3.6+/-1.3) micron respectively (P<0.05) in hypertrophied cardiomyocytes, while did not change calcium sensitivity in both groups. KB-R7943 completely blocked the activating effects induced by E-4031 in both of normal and hypertrophied cardiomyocytes. Nicardipine did not block the increasing effects of E-4031., Conclusion: E-4031 increased Ca2+ transient and cell contraction via stimulating reverse mode of Na+/Ca2+ exchange while without influencing calcium sensitivity. These effects were more notable in hypertrophied cardiomyocytes than in normal myocytes.

The effects of 5-(N,N-dimethyl)amiloride (DMA) (a blocker of Na(+)/H(+) exchanger or Na(+)/Ca(2+) exchanger) on calcium transient and cell contraction in isolated ventricular myocytes in normal rats and rats with myocardial hypertrophy were examined using ion imaging system with a charge coupled digital camera (CCD camera). Loading myocytes with Fura-2, electrically triggered Ca(2+) transients and cell shortening were measured simultaneously. The results showed that 10 micromol/L DMA increased Ca(2+) transient and cell shortening from 209.60+/-54.96 and 3.07+/-0.97 micrometer to 238.50+/-80.41 and 4.07+/-1.02 micrometer, respectively (P<0.05), which was completely abolished by application of KB-R7943, a specific reverse mode Na(+)/Ca(2+) exchanger blocker. After blocking L-type Ca(2+) channels by nicardipine, DMA also enhanced Ca(2+) transient and cell shortening. In rats with myocardial hypertrophy, DMA showed the common pharmacologic profile as in normal rats but more intense stimulating effects on Ca(2+) transient and cell contraction. The results suggest that DMA increase Ca(2+) transient and cell contraction via stimulating reverse mode Na(+)/ Ca(2+) exchange, and the stimulating effect is more pronounced in rats with myocardial hypertrophy than in normal ones.