NOD2 contributes to myocardial ischemia/reperfusion injury by regulating cardiomyocyte apoptosis and inflammation.

AIMS: Nucleotide-binding oligomerization domain-containing protein 2 (NOD2), an intracellular pattern recognition receptor, which plays an important role in the innate immunity and inflammation. However, its role in myocardial ischemia/reperfusion (I/R) injury remains unknown. In this study, we sought to determine the role of NOD2 on cardiac I/R injury. MAIN METHODS: Mice were induced 30min ischemia followed by 24h of reperfusion. Histological examinations were performed on heart sections with Evans blue and triphenyltetrazolium chloride (TTC) staining, hematoxylin and eosin (H&E) staining, immunohistochemistry and immunofluorescence staining. The messenger RNA (mRNA) expression and protein levels were detected by real-time polymerase chain reaction (RT-PCR) and western blot analysis respectively. KEY FINDINGS: I/R injury markedly upregulated NOD2 expression in heart tissue. Treatment of WT mice with NOD2 ligand (MDP) significantly increased infarct size, the number of apoptotic cells and inflammatory cells, as compared with wild-type mice after I/R injury. Furthermore, MDP enhanced I/R-induced cardiomyocyte apoptosis and inflammation in vitro, and these effects were attenuated by NOD2-siRNA. The mechanism of NOD2 on cardiac I/R injury is partly associated with JNK, p38MAPK and NF-κB signaling pathways. SIGNIFICANCE: NOD2 aggravates myocardial I/R injury by inducing cardiomyocyte apoptosis and inflammation through JNK, p38MAPK and NF-κB signaling pathways. This study provides insight into better understanding the molecular mechanism of NOD2, which may be served as a potential target for the treatment of myocardial I/R injury.

Sustained-release oxycodone tablets for moderate to severe painful diabetic peripheral neuropathy: a multicenter, open-labeled, postmarketing clinical observation.

OBJECTIVE: To evaluate the efficacy and safety of sustained-release (SR) oxycodone tablets in the treatment of moderate to severe painful diabetic peripheral neuropathy (DPN). Design. This was a multicenter, randomized, open-labeled study. SETTING: This study was completed in 12 hospitals in China. PATIENTS: A total of 80 Chinese patients undergoing moderate to severe painful DPN. INTERVENTIONS: An initial dose of 10mg is recommended to be taken orally every 12 hours. Dose titration was done appropriately according to pain intensity and adverse reactions. OUTCOME MEASURES: Data record included days, dosage, analgesic efficacy, quality of sleep, adverse events, and combination therapy when patients were treated with SR oxycodone tablets. The continuous observation period was 6 weeks. RESULTS: After medication for 1 week, pain was significantly (P<0.01) relieved from 6.8±1.4 to 2.8±1.6. Onset time was within 45 minutes in nearly 60% of the patients, and within 1 hour in nearly 95% of that ones. More than 90% of the patients achieved stable analgesic dose within 3 days. After using SR oxycodone tablets for 1 week, sleep quality was significantly (P<0.01) improved. In week 1, the average dose of SR oxycodone tablets was 16.63±7.79mg. The average daily dose of most patients was about 20mg after 2 weeks. In all the enrolled patients, 38 (47.5%) had adverse reactions. No serious adverse reactions took place. CONCLUSION: The results of this clinical observation further elaborated the efficacy and safety of SR oxycodone tablets in the treatment of moderate to severe painful diabetic peripheral neuropathy in China.

[Expression of HIC-5/ARA55 in colonrectal cancer and its mechanisms of action].

OBJECTIVE: To investigate the relationship between HIC-5 and colonrectal cancer. METHODS: Samples were obtained from 42 patients with colonrectal cancer, and the mRNA and protein expressions of HIC-5/ARA55 were determined by RT-PCR and Western-blot respectively. FCM was used to investigate the apoptosis of Lovo in the HIC-5/ARA55 transfection cells. The expression of apoptosis related proteins Bax and Bcl-2 was determined by Western-blot, and the MTT assay was used to test cell growth speed affected by HIC-5/ARA55. RESULTS: The expression of HIC-5 significantly decreased on colonrectal cancer tissues as compared with adjacent normal tissues on mRNA level and protein level(P<0.05). The apoptosis rate increase significantly in the HIC-5/ARA55 transfected cells. HIC-5/ARA55 could restrain tumor cell grow speed. CONCLUSION: HIC-5/ARA55 is the protein that can reduce tumor cell growth rate, and induce apoptosis in colonrectal cancer cells.

[Expression of proline-rich tyrosine kinase-2 (Pyk2) in gastric carcinoma and its significance].

OBJECTIVE: To investigate whether proline-rich tyrosine kinase-2 (Pyk2) is expressed differently in normal gastric mucosas and gastric carcinoma tissues and further to evaluate its significance. METHODS: Expressions of Pyk2 in 59 cases of normal gastric mucosas and 52 cases of gastric carcinoma tissues were analysed by immunohistochemical methods. RESULTS: Immunohistochemical studies showed that the positive rates of Pyk2 protein expression in normal gastric mucosas and gastric carcinoma tissues were 86.44% (51/59) and 19.23% (10/52) respectively. The difference between normal gastric mucosas and gastric carcinoma tissues was statistically significant (P<0.05). The positive rates of Pyk2 expression in highly differentiated gastric carcinoma and moderately/lowly differentiated gastric carcinoma were 47.37% (9/19) and 3.03% (1/33) respectively. Statistically significant differences (P<0.05) were observed in the levels of Pyk2 expression between highly differentiated gastric carcinoma and moderately/lowly differentiated gastric carcinoma. The positive rates of Pyk2 expression at different TNM stages gastric carcinoma were respectively: stage I 66.67% (6/9), stage II 30% (3/10), stage III 3.45% (1/29), stage IV 0% (0/4). The differences were statistically significant [(II+III+IV) v I, chi2=15.767, P<0.05]. CONCLUSION: In this study, we demonstrate that Pyk2 is expressed in normal gastric mucosas, whereas its expression declines significantly or almost disappears in gastric carcinoma tissues. The expression of Pyk2 progressively decreases with increasing grade of malignancy and TNM stages of gastric carcinoma. This phenomenon indicates that Pyk2 expression may be involved in the generation and development of gastric carcinoma.

[Sequence of Escherichia coli O138 O-antigen gene cluster and gne identification by bioinformatics].

E. coli O138 is one of the enterotoxigenic Escherichia coli, causing the postweaning diarrhea and edema disease of weaned pigs. The O-antigen gene cluster of E. coli O138 was sequenced and found to contain the genes rmlB-DAC and gne, gna for the biosynthesis of nucleotide sugars dTDP-rhamnose and UDP-GalNAcA, respectively, genes encoding for O unit flippase(wzx), O-antigen polymerase(wzy) and 3 potential transferase genes. The possible biosynthesis pathway for rare UDP-GalNAcA was proposed. Two genes specific to E. coli O138 were identified. This work provides the basis for a sensitive test by PCR for the rapid detection of E. coli O138. Phylogenetic tree for Gne and GalE proteins was generated and comparisons were made among different strains, and results revealed that these proteins are similar in the second structure, and Gne of E. coli O138 was identified by bioinformatics.

[Sequence of Escherichia coli O141 O-antigen gene cluster and analyses of its evolutionary history].

Lipopolysaccharide (LPS) is one of the major components of the outer membrane of gram-negative bacteria. It is an amphipathic molecule compose of lipid A, a core oligosaccharide and an O-specific antigen. O-antigen, which is a repeat-unit polysaccharide, is a major contribution to the antigenic variability of the bacterial cell surface. The genes of O-antigen gene cluster are responsible for the synthesis of the O-antigen. The O-antigen gene cluster of E. coli O141 was sequenced and found to contain the genes rmlBDAC and manBC for the biosynthesis of nucleotide sugars dTDP-rhamnose and GDP-mannose, respectively, encoding genes for Ounit flippase (wzx), O-antigen polymerase (wzy) and potential transferase genes. The possible biosynthesis pathway for O-antigen of E. coli O141 was proposed. Two genes specific to E. coli O141 were identified. This work provides the basis for a sensitive test by PCR for the rapid detection of E. coli O141. Phylogenetic trees for the rmlB, rmlD, rmlA, and rmlC genes and manB, manC genes were generated and the comparisons were made among different strains. We find that these genes are typical E. coli genes and might have been involved in recombination events between O-antigen gene clusters.