Unusual dTDP-sugars are key intermediate in many pathogenic bacteria. In this study, negative-ion electrospray tandem mass spectrometry (ESI-MS-MS) with collision-induced dissociation (CID) was used to study the fragmentation characteristics of six unusual nucleotide diphosphate sugars. The results indicated the major fragment of the six unusual nucleoside sugars observed in the ESI-MS-MS spectra resulted from cleavage of diphosphate moiety and their characteristic fragment ions at m/z 401, 383, and 321, correspond to [TDP-H] together with fragment ions resulting from the loss of water and phosphate moiety, respectively. Furthermore, 4-position substituted change of unusual sugar rings affected the stability of two important characteristic fragment ions of [glycosyl-1"-PO3](-) and [glycosyl-1"-P2O6](-).

Objective To investigate the protective effect of glycine (Gly) on hypoxic injury to murine cardiomyocytes and the mechanisms. Methods The survival rate of cardiomyocyte survival was detected by trypan blue exclusion and lactate dehydrogenase (LDH) with an ultraviolet spectrophotometer. Ca 2+ changes in the cardiomyocytes were detected by laser confocal microscopy. Results Glycine markedly improved the survival rate of cardiomyocytes and decreased the release of LDH in cardiomyocytes after hypoxia. The protective effect was in a dose-dependent manner. Glycine could also block calcium overload after hypoxia. Conclusion Glycine has the protective effect on cardiomyocytes through the improvement of survival rate, decrease of LDH release, and blockage of calcium overload after hypoxia.

Objective To examine the levels of serum adipaneetin in patients with incipient chronic kidney disease (CKD, GFR≥ 60ml/min, and identify the relationship between serum adiponectin and albumin (ALB), urinary protein excretion amount, blood lipid and renal function. Methods Forty-two CKD patients and twenty normal healthy persons were involved in this study. These patients were divid- ed into two groups: nephrotic syndrome and non-nephrotic syndrome. The level of serum adiponectin, serum ALB, urinary protein excretion amount, blood lipid, renal function were measured and compared. Results The level of serum adiponectin in nephritic syndrome patients [(21.9±11.3) mg/L] and non-nephrotic syndrome patients [ ( 11.0±7.0) mg/L] was significantly higher than that in normal healthy per- sons[ (5.6±3.3) mg/L] ( P<0.01 ), and the level of serum adiponectin in nephritic syndrome patients was higher than that in non-ne- phrotic syndrome patients( P <0.01 ). Correlative analyses revealed a negatively correlation between serum adiponectin and serum total pro- tein(TP, ALB, BMI( r=-0.5680, r = -0.6241, r = -0.4083,respectively), and a positive correlation between serum adiponectin and urinary protein excretion amount ( r =0.4083). Stepwise regression analyses showed that serum adiponoctin was highly influenced by BMI, ALB and urinary protein excretion amount. Conclusion Serum adipanectin was markedly increased in incipient CKD, especially in patients with macroalbuminura. The effect of high level adiponectin in CKD was still not clear.

OBJECTIVE: To investigate the effect of arsenic trioxide (As2O3) combined with cisplatin on expression of RASSF1A in nude mice with human nasopharyngeal carcinoma xenograft. METHOD: The models of human poorly differentiated nasopharyngeal carcinoma in nude mice were established and randomly divided into four groups, control group (NaCl group), As2O3 group, DDP group and As2O3 + DDP group. The expression of RASSF1A mRNA and protein were detected by Real-time RT-PCR and immunohistochemistry respectively. The methylation rate of RASSF1A promoter CpG islands was analyzed by HRM. RESULTS: Experimental groups could obviously inhibit the growth of tumor and up-regulate the expression of RASSF1A. The methylation rate of RASSF1A in transplanted tumors in experimental groups was lower than the control group. Especially As2O3 combined with DDP were superior to the single drug use. CONCLUSION As2O3 inhibits the growth of human nasopharyngeal carcinoma cell strain CNE2 xenograft in nude mice and increases mRNA expression of RASSF1A. As2O3 inhibits the malignant phenotypes of human nasopharyngeal carcinoma cells and reverses hypermethylation of RASSF1A.
Animals ; Arsenic Trioxide ; Arsenicals ; pharmacology ; Carcinoma ; Cell Line, Tumor ; Cisplatin ; pharmacology ; DNA Methylation ; drug effects ; Humans ; Mice ; Mice, Nude ; Nasopharyngeal Carcinoma ; Nasopharyngeal Neoplasms ; genetics ; pathology ; Neoplasm Transplantation ; Oxides ; pharmacology ; Tumor Suppressor Proteins ; genetics ; Xenograft Model Antitumor Assays

The LasR gene was amplified from the genome of Pseudomonas aeruginosus by PCR and recombined with plasmid pUCP18 reversely. The recombinant pUCP18/lasRantisense was verified with restriction analysis, PCR and sequence and was transformed in Pseudomonas aeruginosus. The biological effect of pUCP18/lasRantisense was detected by RT-PCR, NAD method and the assay of pyocyanin. The air tubes of rats were infected by pUCP18/lasRantisense strain and then carried on histopathologic slide check. Expected full length LasR fragment (721bp) can be extended from Pseudomonas aeruginosus gene with PCR technology. And it is consistent with LasR gene of Pseudomonas aeruginosa covered in GenBank (NO. NC_002516). The recombinant plasmid was constructed and transformed into Pseudomonas aeruginosus sucessfully. Compared with the rats which were infected by standard strain, the bronchitis of the rats which were infected by pUCP18/lasRantisense strain was obviously eased. It can be concluded that the antisensenucleic acid of LasR gene can depress the virulence of Pseudomonas aeruginosus and reveal a new target site for treatment.

The O152 antigens of Escherichia coli contains a Glc-β-1,3-GlcNAc linkage within the repeating unit. The wfgD gene in E. coli O152 O antigen gene cluster had been demonstrated utilizing NMR technique to encode a glucosyltransferase which is responsible for the synthesis of Glc-β-1,3-GlcNAc linkage. In this study, a synthetic substrate analog of the natural acceptor substrate undecaprenol-pyrophosphate-lipid [GlcNAc-α-PO_3-PO_3-(CH_2)_(11))-O-phenyl]) was used as an acceptor and UDP-Glc as a donor substrate, and electrospray ionization tandem mass spectrometry(ESI-MS-MS) was used for the detailed structural characte-)rization) of the enzyme product. A systematic study was conducted on product to allow rationalization of the fragmentation) processes. The major fragments observed in the ESI-MS-MS spectra result from cleavage of glycosidic) bond and diphosphate moiety. The fragment originating from the nonreducing end of the product yields information on sequence). Cross-ring cleavages, which are very informative of the linkages of the monosaccharide residues constituting) the product, and "internal" cleavage ions which are derived from elimination of substituents from around) the pyranose ring, were also observed. This extensive fragmentation was shown that the expected Glc-β-1,3-GlcNAc linkage in the product, confirming that wfgD is in the form of UDP-Glc: GlcNAc-pyrophosphate-lipid β-1,3-glucosyltransferase.)

OBJECTIVE:To investigate the effect and clinical significance of radiotherapy on the expression of multidrug resistance-associated protein(MRP) in advanced cervical cancer.METHODS:The immunohistochemistry method was applied to detect the expression of lung resistance protein(LRRP),glutathione-S-transferases-?(GST-?),thymidylate synthetase(TS) and type Ⅱ topoisomerase(TopoⅡ) in 23 patients with advanced cervical cancer before radiotherapy and after receiving 30 Gy dose radiation.RESULTS:The positive expression rates of LRRP,GST-?,TS and TopoⅡ before radiotherapy were 47.8%,56.5%,30.4% and 60.9%,respectively.The positive expression rates of LRRP,GST-? and TS in patients after 30 Gy dose radiation were 69.6%,73.9% and 73.9%,respectively,which were signficantly higher as compared before radiotherapy(P

Objective To investigate the resistance of carbapenems,the production of metallobeta-lactamases(MBLs)and homology analysis of Psendomonas aeruginosa in China.Methods A total of 654 Pseudomonas aeruginosa isolates were collected from 28 hospitals in 16 difierent regions during the period from July 2006 to July 2007 as part of the Nosocomial Pathogen Resistance Surveillance(NPRS).MICs of imipenem and meropenem were determined by agar dilutiom PFGE was used to analyze the molecular epidemiology of carbapenem-resistant strains.MBLs were detected by Etest and PCR among carbapenem-non-sensitive strains.The transcription levels of MBLs were determined by real-time reverse transcriptase(RT)-PCR.Results Of the 645 Pseudomonas aeruginosa strains,245(37.5%)were resistant to imipenem and 183(28.0%)were resistant to meropenem.A total of 275 carbapenemnonsusceptible strains and 259 carbapenem-resistant strains were chosen for further study. Among the carbapenem-nonsusecptible strains,8.73%(24/275)of the strains carrried MBLs genes hy PCR,but only 6.55%(18/275)of the strains were detected as MBls-producers bv MBL Etest. The MBLs relative expression levels of the 6 MBL genotype-positive but phenotype-negative strains were significantly lower than those of the other 18 MBL genotype-and phenotype-positive strains(P＜0.05).The 259 carbapenemresistant Pseudomonas aeruginosa strains were divided into 89 clones by PFGE.The 24 MBL genotypepositive strains collected from 6 cities were divided into 9 clones by PFGE.Conclusions The carbapenems resistance of Pseudomonas aeruginosa is severe in China.Clonal dissemination of Pseudomonas aeruginosa has not been detected throughout China.MBLs are not the major carbapenems resistance mechanism in Pseudomonas aeruginosa.

Objective To examine the levels of serum adipunectin (ADPN)in patients with end-stage renal disease (ESRD), and identify the relationship between serum ADPN and tumor necrosis factor (TNF)-α, high sensitivity C-reactive protein(hs-CRP) and renal function. Methods Sixty ESRD patients and twenty normal healthy persons were involved in this study. The patients were divided into three groups: patients with chronic renal failure (CRF, 18 cases), patients with hemodialysis (HD,22 cases) and patients with peritoneal dialysis (PD,20 cases). The levels of serum ADPN, TNF-α and hs-CRP were detected by means of ELISA. Differences in continuous variables be-tween the three groups were evaluated. Results The levels of serum ADPN, TNF-α and hs-CRP in CRF, HD and PD patients were signifi-cantly higher than those in control group ( P<0.01 ). Serum ADPN levels in ESRD patients were positive related to serum TNF-α( r≥0.478, P<0.01 ), and negative related to GFR ( r≥-0.582, P<0.01 ). Conclusion The level of serum ADPN was markedly in-creased in patients with ESRD, and correlated with serum TNF-α level and.renal function.

Objective To investigate the efficacy of laparoscopic percutaneous common bile duct exploration (LPCBDE) with internal draining tube placement for the treatment of cholelithiasis. Methods The clinical data of 962 patients with choledocholithiasis who were admitted to the No. 451 Hospital of PLA were retrospectively analyzed. A self-made internal draining tube was placed in the common bile duct and duodenum to drain bile internally. The correct position of the internal draining tube was comfirmed by injecting water into and draining water from duodenum. The internal draining tube was pulled out with the help of duodenoscope at 30 days after the operation. Results LPCBDE with internal draining tube placement was successfully performed on 864 patients. Forty-two patients were transferred to open surgery, and 56 patients were transferred to receive LPCBDE with T-tube drainage. The mean operation time was (36 ± 18) minutes (range, 20-72 minutes), and the length of postoperative hospital stay was (6.6 ±2.1)days. Two patients were complicated with retroperitoneal abscess and they were cured by puncture and drainage, 32 patients were complicated with bile leakage and they were cured by conservative treatment. A total of 862 patients were followed up by B ultrasound at 30 days after the operation. The internal draining tube which was confirmed in the common bile duct was extracted with duodenoscope in 603 patients; the internal draining tube which was drawn back in 1 patient was removed with endoscopic sphincterotomy ( EST); the internal draining tube was removed naturally in 258 patients. The follow-up period ranged from 1 to 3 years, 26 patients had recurrent cholelithiasis and they were treated by EST. Conclusions LPCBDE with internal draining tube placement is a safe and minimally invasive method for the treatment of cholelithiasis.