RTKN2 Enhances Radioresistance in Gastric Cancer through Regulating the Wnt/ß-Catenin Signalling Pathway.

Adjuvant therapy and radiotherapy improves the survival of patients with metastatic and locally advanced gastric cancer (GC). However, the resistance to radiotherapy limits its clinical usage. Rhotekin 2 (RTKN2) functions as an oncogene and confers resistance to ultraviolet B-radiation and apoptosis- inducing agents. Here, the role of RTKN2 in radiosensitivity of GC cell lines was investigated. RTKN2 was found to be elevated in GC tissues and cells. A series of functional assays revealed that overexpression of RTKN2 induced GC cell proliferation, promoted GC cell migration and invasion, while inhibiting GC cell apoptosis. However, silence of RTKN2 promoted GC cell apoptosis, while repressing GC cell proliferation, invasion and migration. GC cells were exposed to irradiation, and data from cell survival and apoptotic assays showed that knock-down of RTKN2 enhanced radiosensitivity of GC through up-regulation of apoptosis and down-regulation of proliferation in irradiation-exposed GC cells. Moreover, the protein expression of ß-catenin and c-Myc in GC cells was enhanced by RTKN2 over-expression, but reduced by RTKN2 silence. Interference of RTKN2 down-regulated nuclear ß-catenin expression, while up-regulating cytoplasmic ß-catenin in GC. In conclusion, RTKN2 contributed to cell growth and radioresistance in GC through activation of Wnt/ß-catenin signalling.

Optimization of culture conditions for penicilazaphilone C production by a marine-derived fungus Penicillium sclerotiorum M-22.

The aim of this study was to optimize the culture conditions of a marine-derived fungus Penicillium sclerotiorum M-22 for the production of penicilazaphilone C (PAC), a novel azaphilonidal derivative exhibiting broad cytotoxic and antibacterial effects. By single factor experiments, the effects to the production of PAC of aged seawater concentration, initial pH values, fermentation time, carbon sources, nitrogen sources and inorganic salt sources were investigated individually. Response surface methodology (RSM) analysis was adopted to investigate the interactions between variables and determine the optimal values for maximum PAC production. Evaluation of the experimental results signified that the optimum conditions for maximum production of PAC (19·85 mg l-1 ) in 250 ml Erlenmeyer flask were fermentation time 24·83 days, pH of 7·00, corn meal concentration of 10·72 g l-1 , yeast extract concentration of 4·58 g l-1 , crude sea salt concentration of 20·59 g l-1 . Production under optimized conditions increased to 1·344-fold comparing to its production prior to optimization. The higher PAC production and the penicilazaphilone C -producing marine fungus would be provide a promising alterative approach for industrial and commercial applications. SIGNIFICANCE AND IMPACT OF THE STUDY: Penicilazaphilone C (PAC) was a novel azaphilonidal derivative which had exhibited selective cytotoxicity and antibacterial activity. To further enhance production of PAC by optimizing fermentation conditions of Penicillium sclerotiorum M-22 would provide a promising alterative approach for industrial and commercial applications. We used the single factor test to determine the key factors which influence the PAC production. Then through the Response surface methodology and Box-Behnken design to determine the best fermentation condition for maximum production of PAC. Through these experimental designs and analysis will help us improve experimental efficiency and save time and materials.

[Feasibility of screw placement on posterior occipital condyle assisted by occipital tangent angulation].

Objective: To investigate the practicability of occipital tangent angle in assisting posterior occipital condylar screw placement and to verify the safety and accuracy of self-made screw placement device for auxiliary screw. Methods: Occipito-cervical region specimens of 12 adult corpses were selected and scanned by thin-cut CT examination.The three-dimensional reconstruction of occipital and atlas was simulated for each specimen, and 3-matic software was used to measure the setting parameters, including occipital tangent angle, head obliquity, internal inclination angle, length of the screw and the distance from the inferior margin of hypoglossal canal to the screw axis.Using the self-designed occipital condylar screw placement device, combined with occipital tangent angle, internal inclination angle and insertion point, the posterior occipital condylar screw specimen was inserted with nails with assisting tool.The occipito-cervical region was reconstructed and scanned by thin-cut CT examination again after the operation to measuring the parameters of screw placement after actual screwing.The paired t test was used to compare the parameters of screw placement before and after operation. Results: Pre-operative three dimensional reconstruction of occipital condyle screw showed that the head obliquity was 5.3°±0.9°, the tangent angle was 14.9°±3.7°, the internal inclination angle was 28.1°±5.9°, and the length of screw insertion was (21.4±1.7) mm respectively; the distance from the inferior margin of hypoglossal canal to the screw axis was (4.74±0.36) mm.There was no significant difference in the parameters of analogue nailing between the left and right occipital condyles before the operation (t=-1.32, -0.48, 0.10, 0.23, 0.09, all P>0.05). The occipital condylar screw was safely implanted with screw placement device.The screw was located in the ideal nail insertion channel after operation by CT scan evaluation, without any injury to the hypoglossal canal, the atlanto-occipital articular surface and other structure.After the operation, the actual nailing parameters were measured: the head inclination angle was 5.2°±0.7°, the tangent angle was 15.1°±3.2°, the internal inclination angle was 28.2°±4.2°, the length of screw insertion was (21.5±1.7) mm, the distance from the inferior margin of hypoglossal canal to the screw axis was (4.54±0.29) mm.There was no significant difference between the left and right side in the actual screw placement parameters (t=-0.77, 0.82, 0.56, 0.22, 0.21, all P>0.05). It was found that there was no significant differences in the head obliquity, the occipital tangent angle, the internal inclination angle, length of screw entry, and the distance from the inferior margin of hypoglossal canal to the screw axis before and after the operation (t=0.56, -0.47, -0.18, -0.70, 1.89, all P>0.05). Conclusion: The occipital tangent angle can be measured directly in the process of posterior occipital condyle screw insertion to guide occipital condylar screw insertion, and the self-made occipital condylar screw placement device can effectively combine the three parameters: occipital tangent angle, head inclination angle and insertion point, which can improve the safety of posterior occipital condylar screw insertion.

[Clinical efficacy and safety of thrombolytic treatment with reteplase in patients with intermediate-risk acute pulmonary embolism].

Objective: To assess the efficacy and safety of thrombolytic treatment with reteplase in patients with intermediate-risk acute pulmonary embolism. Methods: Ten consecutive patients with intermediate-risk acute pulmonary embolism who received thrombolytic treatment with reteplase at Thrombosis and Vascular Medicine Center, Fuwai Hospital from March to November in 2016 were included.Vital signs, right ventricular diameter, systolic pulmonary artery pressure, and biochemical markers were assessed before and after thrombolytic therapy with reteplase, and bleeding complications were also observed during 3 months follow up. Results: (1) For the efficacy outcomes: at 48 hours after thrombolytic treatment with reteplase, echocardiography-derived diameter of right ventricular was significant reduced from (27.9±3.8) mm to (24.8±2.6) mm (P=0.03), systolic pulmonary artery pressure decreased from (63.9±21.6) mmHg(1 mmHg=0.133 kPa) to (34.4±19.8) mmHg (P=0.02). Heart rate and breathing rate were also decreased significantly (both P<0.05), blood pressure remained unchanged post therapy.Hypoxemia was quickly corrected with an significant elevation of PaO(2) and SaO(2) ((65.2±14.3) mmHg vs. (80.0±9.6) mmHg, P=0.006; (90.8±3.5)% vs. (95.2 ±1.6)%, P=0.002 respectively). PaCO(2) was also increased significantly (P<0.05). Serum NT-proBNP and cTnI were decreased significantly (both P<0.05). There was no recurrent pulmonary embolism or deep-vein thrombosis during the 3 months follow-up. (2) For the safety outcomes: a thrombolytic relevant hemoptysis (about 70 ml) occurred in 1 patient, and was controlled by PCC therapy.No other clinically relevant events were observed during thrombolytic treatment. Eight patients were followed more than 3 months, there was no major bleeding complication or death during the follow up period. Conclusion: Treatment of intermediate-risk acute pulmonary embolism with reteplase is effective and safe and there are no obvious side effects.

[Efficacy and safety of generic azacitidine in Chinese patients with higher-risk myelodysplastic syndromes: a multicenter, prospective, single-arm study].

Objective: To evaluate the efficacy, safety, and pharmacokinetics of the generic azacitidine in Chinese patients with higher-risk myelodysplastic syndromes(MDS). Methods: Between October 2013 and 2016, 72 patients were eligible for enrollment at 9 sites from China received generic subcutaneous azacitidine 75 mg·m(-2)·d(-1) for 7 days per 28-day cycle, for ≥6 cycles. Pharmacokinetic blood samples were collected on day 1 of a single-dose. Results: For each patient at cycle 6 or at the time of study discontinuation, whichever came first, the overall response rate, which included complete remission (CR)and partial remission(PR), was 6.9%(5/72), the rate of patients who had the best effect with CR or PR during the treatment was 12.5%(9/72). Patients who were dependent on red-blood-cell transfusions and platelet transfusions at baseline became transfusion independent were 46.3%(19/41)and 41.2% (7/17), respectively. The median time of treatment was 6 cycles, and the median OS was 16.1 months (95%CI 10.9-20.6 months). For 36 patients(50%)received treatment at ≥6 cycles, and the median OS was 22.3 months(95%CI 16.1- not evaluative). Most common grade Ⅲ-Ⅳ hematologic treatment-emergent adverse events were neutropenia(55%), leukopenia(47%), and thrombocytopenia(61%). Pharmacokinetic profiles were similar for generic and original azacitidine in Chinese patients. Conclusion: Generic azacitidine treatment was favorable and safe and can be used as a standard treatment for patients with higher-risk MDS.

[Efficacy and safety of IA regimen containing different doses of idarubicin in de-novo acute myeloid leukemia for adult patients].

Objective: To investigate the efficacy and safety of IA regimen which contains idarubicin (IDA) 8 mg/m(2), 10 mg/m(2) or 12 mg/m(2) as induction chemotherapy for adult patients with de-novo acute myeloid leukemia (AML) . Methods: A total of 1 215 newly diagnosed adult AML patients, ranging from May 2011 to March 2015 in the First Affiliated Hospital of Soochow University and other 36 clinical blood centers in China were enrolled in the multicenter, single-blind, non-randomized, clinical controlled study. To compare the response rate of complete remission (CR) , adverse events between different dose idarubicin combined with cytarabine (100 mg/m(2)) as induction chemotherapy in newly diagnosed patients of adult AML. Results: Of 1 207 evaluable AML patients were assigned to this analysis of CR rate. The CR rates of IDA 8 mg/m(2) group, IDA 10 mg/m(2) group and IDA 12 mg/m(2) group were 73.6% (215/292) , 84.1% (662/787) and 86.7% (111/128) , respectively (P<0.001) . After adjusted for age, blast ratio of bone marrow, FAB classification and risk stratification, the odds ratios (95% CI) of IDA 10 mg/m(2) group and IDA 12 mg/m(2) group were 0.49 (0.34-0.70) and 0.36 (0.18-0.71) , as compared with the IDA 8 mg/m(2) group (P<0.001, P=0.003) . In the intermediate and favorable groups, CR rates was 76.5% (163/213) , 86.9% (506/582) and 86.1% (68/79) in different doses of IDA (P=0.007) . Interestingly, IA regimen with IDA 10 mg/m(2) was the only beneficial factor affecting CR in this group after adjusted for age, blast ratio of bone marrow and FAB classification[OR=0.47 (95% CI 0.31-0.71) , P<0.001]. CR rates in adverse group was 50.0% (18/36) , 60.6% (43/71) and 81.8% (18/22) respectively (P=0.089) . However, the odds ratios (95% CI) of IDA 12 mg/m(2) when compared with the IDA 8 mg/m(2) was 0.22 (0.06-0.80) , after adjusted for age, blast ratio of bone marrow and FAB classification. The median time (days) of neutrophil count less than 0.5×10(9)/L in IDA 8 mg/m(2) group, IDA 10 mg/m(2) group and IDA 12 mg/m(2) group were 14 (11-18) , 15 (11-20) and 18 (14-22) , respectively (P=0.012) and of platelet count lower than 20×10(9)/L were 14 (7-17) , 15 (11-20) and 17 (15-21) , respectively (P=0.001) . The incidences of lung infection in the three groups were 9.8%, 13.5% and 25.2%, respectively (P<0.001) . Conclusions: For young adult patients (aged 18-60 years) with AML in China, intensifying induction therapy with idarubicin 10 mg/m(2) is clinically superior to IDA 8 mg/m(2) and IDA 12 mg/m(2) in favorable intermediate AML subgroup. However, idarubicin 12 mg/m(2) is more suitable to adverse AML subgroup.

Silver nanoparticle film induced photoluminescence enhancement of near-infrared emitting PbS and PbS/CdS core/shell quantum dots: observation of different enhancement mechanisms.

The photoluminescence (PL) enhancement of a Ag nanoparticle and near-infrared quantum dots (QD) plasmon/fluorophore system was investigated. Different enhancement mechanisms were obtained by tuning surface plasmon resonance of the Ag film and PL of the QDs. A maximum enhancement factor of 2.8 was achieved.

Genotype-phenotype correspondence in Sanfilippo syndrome type B.

Sanfilippo syndrome type B, or mucopolysaccharidosis type IIIB, results from defects in the gene for alpha-N-acetylglucosaminidase (NAGLU); only a few mutations have been described. To rapidly identify most NAGLU mutations, an automated sequencing procedure was developed for analysis of the entire coding region, including exon-intron borders. By this method, eight affected families were studied, and the mutations in all 16 alleles were identified, more than doubling the number of published mutations for this gene. Eight mutations were described for the first time: five missense mutations (Y140C, Y455C, P521L, S612G, and R674C), two nonsense mutations (W675X and Q706X), and one 24-nucleotide insertion. Currently, 36% of all point mutations (8 of 22 alleles) involve R674, a codon having a CpG dinucleotide in the critical initial position. Other mutations were found in more than one family, raising the possibility that some may be relatively common and, possibly, ancient mutations. Six new nonpathological mutations were also identified and likely represent polymorphic variants of the NAGLU gene, two of which might alter enzyme level. Establishing genotype-phenotype relationships will be vital in the evaluation of experimental treatments such as gene therapy.

Study of mechanisms of electric field-induced DNA transfection. IV. Effects of DNA topology on cell uptake and transfection efficiency.

Electric parameters and solvent conditions are known to influence the efficiency of DNA transfection of cells by a pulsed electric field (PEF). A previous study (Neumann, E., M. Schaefer-Ridder, Y. Wang, and P. H. Hofschneider. 1982. EMBO (Eur. Mol. Biol. Organ.) J. 1:841-845) has indicated that DNA topology is also an important determinant. We report an investigation of the PEF induced uptake, stability, and expression of three different topological isomers, circular supercoiled (scDNA), circular relaxed (crDNA), and linearized (lnDNA) forms of the plasmid pBR322, by Escherichia coli strain JM105. Monomeric pBR322 prepared by the electroelution from an agarose gel was in the supercoiled form. Treatment of the scDNA with wheat germ topoisomerase I removed the superhelicity and the DNA assumed the relaxed circular form. Treatment of scDNA by a restriction endonuclease, EcoRI or Hind III, linearized the DNA. The MgCl2-dependent bindings of all three forms of DNA to the cell surface were indistinguishable. So was the PEF induced cell uptake. In contrast, the transfection efficiency (TE) for the scDNA and the crDNA were high (approximately 2 x 10(8) micrograms-1 DNA at neutral pH), whereas that for the lnDNA was approximately five orders of magnitude lower (less than 1 x 10(3) micrograms-1 DNA). Analysis by agarose gel electrophoresis indicated that the PEF loaded ln DNA was degraded by the host cell within 3 h. However, the loaded scDNA and the crDNA were stable and expressed in the cytoplasm. We conclude that first, the PEF induced DNA entry into E. coli did not depend on the topology of the DNA. As cellular uptake of DNA also correlated with the surface binding, these data support electrophoresis of surface bound DNA as the dominating mechanism for the DNA entry. Second, the variations of TE for different topological forms of DNA reflected their relative stability in the host cells. Third, since the loaded DNA could be either rapidly degraded by the host enzyme or expressed, they were unlikely coated with a layer of protective lipid membrane. Thus, PEF induced cellular uptake of DNA is unlikely by the endocytotic mechanisms as was reported previously for the liposomes (Chernomordik, L. V., A. V. Sokolov, and V. G. Budker. 1990.Biochim. Biophys. Acta. 1024:179-183).

The molecular basis of Sanfilippo syndrome type B.

The Sanfilippo syndrome type B is a lysosomal storage disorder caused by deficiency of alpha-N-acetylglucosaminidase; it is characterized by profound mental deterioration in childhood and death in the second decade. For understanding the molecular genetics of the disease and for future development of DNA-based therapy, we have cloned the cDNA and gene encoding alpha-N-acetylglucosaminidase. Cloning started with purification of the bovine enzyme and use of a conserved oligonucleotide sequence to probe a human cDNA library. The cDNA sequence was found to encode a protein of 743 amino acids, with a 20- to 23-aa signal peptide immediately preceding the amino terminus of the tissue enzyme and with six potential N-glycosylation sites. The 8.5-kb gene (NAGLU), interrupted by 5 introns, was localized to the 5'-flanking sequence of a known gene, EDH17B, on chromosome 17q21. Five mutations were identified in cells of patients with Sanfilippo syndrome type B: 503del10, R297X, R626X, R643H, and R674H. The occurrence of a frameshift and a nonsense mutation in homozygous form confirms the identity of the NAGLU gene.

[Effect of progesterone on cerebral cortex edema in rats exposed to focal ischemia/reperfusion].

AIM: To explore the effects of progesterone (PROG) on brain edema in rats. METHODS: Forty eight rats were randomly divided into 6 groups that were ischemia/reperfusion (I/R), dimethylsulfoxide (DMSO), and pretreatment, pre + posttreatment, posttreatment with PROG, and dexamethasone (DEXA) groups. The model of focal cerebral ischemia was established in rats by reversible inserting a nylon thread into the anterior cerebral artery. All rats were decapitated at 24 hours after the left middle cerebral artery occlusion (MCAO) respectively, and then brain H2O, Na+, K+, Ca2+ contents were determined. RESULTS: Compared with the result in DMSO group, the content of water (P < 0.01), Na+ (P < 0.01), Ca2+ (P < 0.01) was significantly reduced, but K+ (P < 0.01) was obviously elevated in ischemia cortex in pretreatment group or pre + posttreatment group with PROG. There was also significant reduction in water (P < 0.05) and Na+ (P < 0.01), but was not significantly changed in Ca2+ (P > 0.05) and K+ (P > 0.05) in posttreatment group with PROG. The changes occurring in DEXA group were similar to those found in pretreatment group or pre + posttreatment group with PROG. CONCLUSION: Pretreatment or pretreatment plus posttreatment with progesterone can significantly reduce brain edema in I/R.

Partial splenic embolization for hypersplenism concomitant with or after arterial embolization of hepatocellular carcinoma in 30 patients.

PURPOSE: To study the value of partial splenic embolization (PSE) for the treatment of hypersplenism in patients undergoing embolization of hepatocellular carcinoma (HCC). METHODS: Transcatheter hepatic arterial embolization (THAE) combined with PSE was performed in 30 patients with HCC complicating liver cirrhosis, portal hypertension, and hypersplenism. Gelfoam sponge was used as the embolic material for PSE and limited to 100-150 pieces. RESULTS: More than 50% of splenic parenchyma was infarcted in 27 patients. Leukopenia and thrombocytopenia were corrected by PSE in 25 of 27 patients with hypersplenism. In 26 patients with esophageal varices, including 5 patients with bleeding, no rebleeding occurred during a 6-17 month follow-up. Hypersplenism was not corrected in 2 of 3 patients whose infarcted splenic parenchyma was less than 50%. No splenic abscesses or other severe complications were observed. Of the 30 patients treated, 19 are still alive after 1 year. CONCLUSIONS: THAE combined with PSE is a safe and effective measure for patients with HCC.

NAGLU mutations underlying Sanfilippo syndrome type B.

Sanfilippo syndrome type B (mucopolysaccharidosis III B) is a rare autosomal recessive disease caused by deficiency of alpha-N-acetylglucosaminidase, one of the enzymes required for the lysosomal degradation of heparan sulfate. The gene for this enzyme, NAGLU, recently was isolated, and several mutations were characterized. We have identified, in amplified exons from nine fibroblast cell lines derived from Sanfilippo syndrome type B patients, 10 additional mutations: Y92H, P115S, Y140C, E153K, R203X, 650insC, 901delAA, P358L, A664V, and L682R. Four of these mutations were found in homozygosity, and only two were seen in more than one cell line. Thus, Sanfilippo syndrome type B shows extensive molecular heterogeneity. Stable transfection of Chinese hamster ovary cells, by cDNA mutagenized to correspond to the NAGLU missense mutations, did not yield active enzyme, demonstrating the deleterious nature of the mutations. Nine of the 10 amino acid substitutions identified to date are clustered near the amino or the carboxyl end of alpha-N-acetylglucosaminidase, suggesting a role for these regions in the transport or function of the enzyme.