[The feasibility analysis of multi-slice spiral CT features of gastric stromal tumors in predicting pathological National Institutes of Health risk classification].

Objective: To investigate the feasibility of multi-slice spiral CT(MSCT) imaging features of gastric stromal tumor (GST) in predicting pathological NIH risk classification, providing imaging basis for patients with GST before treatment. Methods: The clinical and CT imaging data of 504 patients(506 GST lesions), 259males and 245 females, aged from 13 to 85(60±11) years, with GST confirmed by surgery and pathology collected in the Zhongshan Hospital Affiliated to Fudan University and the Affiliated TCM Hospital of Southwest Medical University. According to pathological NIH risk classification, 506 lesions were divided into low risk group (very low and low risk degree, 277 lesions) and high risk group (medium and high risk degree, 229 lesions).Clinical data and imaging characteristics were compared between two groups. Multivariate logistic regression analysis was performed to screen out independent risk factors for statistically significant imaging indicators. Receiver operating curve (ROC) was used to evaluate the predictive value of tumor length for risk classification. Resulst: Between low risk group and high risk group,there were significant differences in gender(male/female:131/146 vs 129/100), gastrointestinal bleeding(present/absent:39/238 vs 59/170), morphology(regular/Irregular:218/59 vs 95/134), calcification(present/absent:36/241 vs 53/176), degree of necrosis(0°/Ⅰ°/Ⅱ°/Ⅲ°:197/61/16/3 vs 58/98/32/41), ulceration(present/absent:32/245 vs 94/135), growth pattern(endophytic/exophytic/mixed:102/105/70 vs 44/98/87), tumor location(fundus/cardia/body/angle/antrum:98/7/135/12/25 vs 98/6/114/5/6), feeding artery(present/absent:32/245 vs 104/125), vascular enhancement(present/absent:19/258 vs 88/141), effusion of around the disease(present/absent:0/277 vs 13/216), positive sign of fat around the disease(present/absent:0/277 vs 30/199),maximum long diameter[2.82(2.04,3.80) cm vs 5.93(4.06,8.29) cm] and short diameter [2.31(1.60,2.88) cm vs 4.40(3.21,6.37) cm]of tumor(all P<0.05).The maximum long diameter of tumor (OR=2.08,95%CI:1.35-3.20) and ulceration positive(OR=2.01,95%CI:1.03-3.92) were independent risk factors of risk classification(all P<0.05).Gastric antrum was used as the reference for tumor location, gastric fundus(OR=7.77,95%CI:2.00-30.24) and gastric body(OR=3.93,95%CI:1.03-15.01) were independent risk factors of risk classification(all P<0.05).The area under curve(AUC) of the maximum long diameter of tumor for predicting risk classification was 0.87, and the optimal critical value, sensitivity and specificity were 4.98cm, 62.9% and 95.3% respectively. Conclusions: MSCT image features of GST had certain characteristics. MSCT has certain predictive value for pathological NIH risk classification of GST, which can provide certain imaging basis for patients before treatment.

[The clinical effect and imaging features of accordion maneuver in promoting bone healing at the docking site after tibial transport under ultrasonic monitoring].

Objective: To explore the imaging features and clinical effect of accordion maneuver in promoting the bone healing at the docking site after tibial transport under ultrasonic monitoring. Methods: Retrospective analysis was conducted on the clinical data of 16 patients with tibial bone transport who were admitted to the Department of Orthopedics, the second Hospital of Shanxi Medical University from May 2018 to October 2019. All the patients were treated with accordion maneuver to promote bone healing at the docking site under ultrasound monitoring. There were 14 males and 2 females, aged (45.3±14.3) years (range: 6 to 61 years). Before tibial bone transport, the length of the tibial defect of 16 patients was (6.0±2.6) cm (range: 2.0 to 12.1 cm). The operation steps of accordion maneuver were as follows: pressurization for 2 weeks, suspension for 12 days, distraction for 2 weeks, retraction for 2 weeks, and then stop the operation to consolidate the bone mineralization. During accordion treatment, ultrasound was used to monitor the size of hematoma, Adler grade of blood flow signal and the changes of new callus in and around the docking site. X-ray was performed to monitor bone healing at the docking site. Pearson correlation coefficient was used to analyze the correlation between the size of hematoma, the resistance index of blood flow signal and the bone healing time of the docking site. Paley healing criterion was used to evaluate the bone healing and functional recovery of the patients. Results: During accordion maneuver, ultrasound examination showed that the Adler grade of blood flow signals around the docking site increased gradually before retraction and then decreased gradually, but the degree of callus mineralization continued to increase gradually. After 2 weeks of pressure on the docking site, hematoma was observed in 14 patients by ultrasound examination. X-ray showed that all docking sites had bony healing, with the healing time of (30.8±4.9) weeks (range: 23 to 40 weeks).The size of the hematoma was negatively correlated with the healing time of the docking site (r=-0.819,P<0.01). No hematoma was found in 2 patients, and after continuous observation for 20 weeks, there was still no obvious callus connection at the docking site. After bone cortical removal, ultrasound examination showed hematoma formed at the docking site. Accordion maneuver was continued, and the docking site healed at 30 and 32 weeks after surgery, respectively. There was a negative linear correlation between hematoma size at 2 weeks of compression and the blood flow resistance index at 2 weeks of retraction in 16 patients (r=-0.801, P<0.01). The patients were followed-up for (14.5±3.2) months (range: 10.6 to 20.2 months). At the last follow-up, 12 patients were evaluated as excellent and 4 were evaluated as good by Paley healing criteria. Conclusion: The distraction and compression stress applied in accordion maneuver can promote bone healing at the docking site, and ultrasound can monitor early signs of bone healing at the docking site to help determine the tendency of bone healing.

Inhibition of ATG12-mediated autophagy by miR-214 enhances radiosensitivity in colorectal cancer.

Radioresistance hampers success in the treatment of patients with advanced colorectal cancer (CRC). Improving our understanding of the underlying mechanisms of radioresistance could increase patients' response to irradiation (IR). MicroRNAs are a class of small RNAs involved in tumor therapy response to radiation. Here we found that miR-214 was markedly decreased in CRC cell lines and blood of CRC patients after IR exposure. Meanwhile, autophagy was enhanced in irradiated CRC cells. Mechanically, ATG12 was predicted and identified as a direct target of miR-214 by dual luciferase assay, qPCR, and Western blot. In vitro and in vivo experiments showed that miR-214 promoted radiosensitivity by inhibiting IR-induced autophagy. Restoration of ATG12 attenuated miR-214-mediated inhibition of cell growth and survival in response to IR. Importantly, miR-214 was highly expressed in radiosensitive CRC specimens and negatively correlated with plasma level of CEA. Moreover, ATG12 and LC3 expressions were increased in radioresistant CRC specimens. Our study elucidates that miR-214 promotes radiosensitivity by inhibition of ATG12-mediated autophagy in CRC. Importantly, miR-214 is a determinant of CRC irradiation response and may serve as a potential therapeutic target in CRC treatment.

The FOXD3/miR-214/MED19 axis suppresses tumour growth and metastasis in human colorectal cancer.

BACKGROUND: MiR-214 is aberrantly regulated in several tumours, but its underlying mechanisms in colorectal cancer (CRC) metastasis remain largely unknown. This study aimed to demonstrate the function and potential mechanism of miR-214 in regulating invasion and metastasis of CRC. METHODS: The transcription factor and targets of miR-214 were predicted by bioinformatics and validated using ChIP and dual-luciferase reporter assay. DNA methylation status was explored using bisulphite sequencing PCR. The in vitro and in vivo function of miR-214 in CRC was evaluated using MTT, plate colony formation, Matrigel invasion and animal models. Real-time PCR or western blotting was performed to detect FOXD3, miR-214 and MED19 expressions in CRC cells and clinical specimens. RESULTS: MiR-214 was downregulated in CRC and was significantly correlated with lymphatic metastasis. Downregulation of miR-214 might due to promoter hypermethylation in CRC. FOXD3 was validated as a transcription factor of miR-214 by ChIP assay. Dual-luciferase assay identified MED19 as a target of miR-214 in CRC. In vitro and in vivo experiments showed that miR-214 mediated the inhibiting effect of FOXD3 on proliferation, invasion and metastasis by targeting MED19. Spearman's correlation analysis showed a positive correlation between FOXD3 and miR-214, and negative correlations between FOXD3 and MED19, miR-214 and MED19 in CRC cells and clinical specimens. CONCLUSIONS: FOXD3/miR-214/MED19 axis is important for the regulation of growth, invasion and metastasis of CRC. Targeting the miR-214-mediated axis might be helpful for the treatment of CRC.

[Effect of mouse nerve growth factor on cognitive impairment in whole brain irradiation rats].

OBJECTIVE: To investigate the positive effects of mouse nerve growth factor(mNGF) on cognitive impairment in whole brain irradiation rats. METHODS: Fifty-five male Sprague-Dawley rats were randomly divided into normal control group, mNGF treated group, saline treated group.mNGF treated group and saline treated group were cranial irradiated at a single dose of 12 Gy by X-ray.30 days after radiation each group were treated with correspondent drugs.60 days after radiation, Morris water maze experiment, EB leakage of the brain, and expressions of neuN, vWF, ZO-1 in hippocampus by immunofluorescence, and expressions of neuN, vWF, ZO-1, VEGF and GFAP in hippocampus by Western blot were tested and analyzed. RESULTS: The escape latencies: normal control group< mNGF treated group< saline treated group; the numbers of crossing hidden platform in these 3 groups were 3.00± 1.08, 1.50± 1.08, 0.38± 0.48 times (P<0.01). EB leakage of these 3 groups were 0.14±0.14, 0.66±0.20 and 1.36±0.27 µg/g (P<0.05). In immunofluorescence, expressions of neuN, vWF and ZO-1: normal control group> mNGF treated group> saline treated group.In Western blot, expressions of neuN, vWF and ZO-1: normal control group> mNGF treated group> saline treated group, yet the expressions of VEGF and GFAP: normal control group< mNGF treated group< saline treated group. CONCLUSION: mNGF ameliorates cognitive impairment after whole brain irradiation.

MicroRNA-206 functions as a tumor suppressor in colorectal cancer by targeting FMNL2.

BACKGROUND: Colorectal cancer (CRC) is one of the most common cancers in the world. MicroRNAs play important roles in the progression of CRC. This study aimed to investigate the role of miR-206 and its novel mechanism in the invasion and metastasis of CRC. METHODOLOGY: Real-time RT-PCR or Western blotting was used to detect the expressions of miR-206, FMNL2 and c-MET in CRC cell lines and tissues. Luciferase reporter assays were conducted to detect the associations between miR-206 and 3'UTRs of FMNL2 and c-MET. A series of loss-of-function and gain-of-function assays were performed to evaluate the effect of miR-206 on the proliferation, invasion and metastasis of CRC cells. RESULTS: miR-206 was significantly down-regulated in CRC tissues and correlated closely with differentiation, lymphatic metastasis and serosal invasion. miR-206 suppressed CRC cell proliferation by arresting CRC cells in the G1/G0 phase and accelerating apoptosis. miR-206 also inhibited cell invasion and lung metastasis in CRC cells. Mechanically, FMNL2 and c-MET were identified as direct targets of miR-206. And FMNL2 rescued the suppression of miR-206 in the proliferation and invasion of CRC cells. CONCLUSIONS: This study revealed functional and mechanistic links between miR-206 and oncogene FMNL2 and c-MET in the progression of CRC. miR-206 functioned as a tumor suppressor in the progression of CRC by targeting FMNL2 and c-MET. Restoration of miR-206 expression may represent a promising therapeutic approach for targeting malignant CRC.

[Current diagnosis and treatment of pseudoaneurysms of the internal carotid artery in postirradiated nasopharyngeal carcinoma].

Nasopharyngeal carcinoma is one of the most common of head and neck malignant tumors in southern region of China. Till date radiotherapy is considered as the first choice of treatment this disease.Although the rate of occurrence of pseudoaneurysms of the internal carotid artery in post radiation treatment of nasopharyngeal carcinoma is low, it is also a hot topic in department of otolaryngology and doctors because of its dangerous and lifethreatening emergencies.In order to improve the level of diagnosis and treatment of the disease, diagnosis, risk, treatment, prognosis and prevention are current summarized in this report.

Polymorphic microsatellite loci from two enriched genomic libraries for the genetic analysis of the miiuy croaker, Miichthys miiuy (Sciaenidae).

Twelve polymorphic microsatellites from the (AG)(13) and (CA)(13) enriched genomic libraries of Miichthys miiuy were isolated and characterized in a test population; the number of alleles ranged from two to nine. The observed and expected heterozygosities ranged from 0.1923 to 1.0000 and from 0.2633 to 0.8337, respectively. Three loci deviated from Hardy-Weinberg equilibrium, and linkage disequilibrium between five pairs of loci was significant. These polymorphic microsatellite loci can be used for genetic diversity analysis and molecular-assisted breeding of M. miiuy.

A mutant alpha-amylase with only part of the catalytic domain and its structural implication.

A truncated mutant alpha-amylase, Xa-S2, was obtained from Xanthomonas campestris wild type alpha-amylases (Xa-WT) through random mutagenesis that contained 167 amino acid residues (approx 65% shorter than that of Xa-WT). Secondary structure prediction implied that Xa-S2, would be unable to form the whole (beta/alpha)(8)-barrel catalytic domain and did not have the three conserved catalytic residues of wild type alpha-amylase, but it still displays the starch-hydrolyzing activity. Xa-S2 was prepared, characterized and compared to the recombinant wild-type enzymes. The K (m) for starch was 32 mg/ml; activity was optimal at pH 6.2 and 30 degrees C. In contrast, the K (m) for starch of Xa-WT was 8 mg/ml and optimal enzyme activity was at pH 6.0-6.2 and 45-50 degrees C. Our results suggested that Xa-S2 is a new amylase with a minimal catalytic domain for hydrolyzing substrates with of alpha-1,4-glucosidic bonds.

In vitro mutagenesis of Xanthomonas campestris alpha-amylase gene by partially replacing deoxythymidine triphosphate with 5-bromo-2'-deoxyuridine-5'-triphosphate using a PCR technique.

Three mutants of the wild type alpha-amylase gene from Xanthomonas campestris pv. campestris 8004 were obtained using a PCR technique in which deoxythymidine triphosphate (dTTP) was partially replaced by 5-bromo-2'-deoxyuridine-5'-triphosphate (BrdUTP), at an optimal dTTP:BrdUTP ratio of 1000:1. Of thre three mutants that were obtained and which were sequenced, one mutant with 40 times higher activity than the wild type alpha-amylase gene product was obtained by using primary PCR products as a template for a second PCR reaction.

Effects of inoculum size and age on biomass growth and paclitaxel production of elicitor-treated Taxus yunnanensis cell cultures.

Suspension cultures of Taxus yunnanensis cells were inoculated with cells of different culture ages (12-24 days) at various densities [50-250 g fresh weight (fw)/l], and treated (on day 7) with a mixture of elicitors, including Ag(+), chitosan and methyl jasmonate. The biomass productivity (during the production stage) increased dramatically with inoculum size, but decreased with inoculum age over 16 days. The volumetric yield and productivity of taxol (paclitaxel) also increased with inoculum size, while the specific taxol yield (per cell) was mainly dependent on inoculum age, with an optimum of 20 days, during the early stationary phase. The highest taxol yield and productivity, 39.8 mg/l and 1.9 mg/l per day, respectively, were obtained with a 20-day-old inoculum at 200 g fw/l. Taxol excretion by the cells increased with inoculum age but decreased with inoculum size. The elicitor-induced activities of catalase (CAT) and phenylalanine ammonia-lyase (PAL) also depended mainly on inoculum age; higher PAL activity and lower CAT activity were obtained with an older inoculum, corresponding to a higher taxol yield. The results show that both inoculum size and age are important variables for taxol production, though the latter more profoundly influences elicitor-induced taxol biosynthesis of the cells. Inoculum size and age are also interrelated and should be optimized together in a two-stage culture process.

Fertile transgenic plants obtained from tritordeum inflorescences by tissue electroporation.

Tissue electroporation was applied to a member of the Triticeae family, namely tritordeum (Hordeum chilense Roem.×Triticum turgidum L. Conv. durum), for the generation of fertile transgenic plants. Two transgenic plants were recovered following the treatment of 361 explants of immature inflorescences (although they were subsequently found to result from the same transformation event). The expression of both inserted marker genes (uidA and bar) was confirmed using standard assays, while transgene integration was confirmed using PCR and Southern hybridization analyses. Integration pattern, segregation ratio and the inheritance of transgene expression in T1 progeny were consistent for the presence of a single transgene locus containing five to ten plasmid insertions. Although this procedure has been applied to other cereal species, stable transformation of the Triticeae using tissue electroporation has not previously been reported.

Attenuation of isoproterenol-mediated myocardial injury in rat by an inhibitor of polyamine synthesis.

OBJECTIVE: Ornithine decarboxylase (ODC) is an initial rate-limiting enzyme in the synthesis of polyamines (putrescine, spermidine, and spermine) that play a role in cell growth and differentiation. Recent studies have shown that spermidine and spermine cause injury to a variety of cells including myocytes in vitro. In this investigation, we used alpha-difluoromethylornithine (DFMO), a specific and irreversible inhibitor of ODC activity and polyamine synthesis to test the hypothesis that polyamines contribute to myocardial injury in rat. METHODS: Male Sprague Dawley rats were treated with (i) saline (0.2 ml/day, s.c.), (ii) isoproterenol (ISO) (5 mg/kg/day for 8 days, s.c.) to produce necrotizing myocardial injury, or with (iii) DFMO + ISO. DFMO was started 2 days before the initiation of ISO and both ISO and DFMO were continued until the end of the experimental period. Myocardial injury was assessed by determining the increased release of creatine phosphokinase (CPK) and lactate dehydrogenase (LDH) into the plasma, and by morphometric analysis of the lesion area in heart sections stained with Gomori trichrome. RESULTS: ISO induced the release of CPK and LDH by 6 hr and 24 hr, respectively, and produced subendocardial necrosis, which was both acute and resolving following 8 days of ISO. DFMO treatment inhibited ISO-induced increases in (i) ODC activity and putrescine and spermidine levels in heart, (ii) CPK and LDH activity in plasma, and (iii) the area of subendocardial lesions. CONCLUSIONS: These observations suggest that polyamines are one of the intracellular factors that contribute to ISO-mediated cardiac injury in the rat.

Mechanism of polyamine toxicity in cultured cardiac myocytes.

The goal of this study was to investigate the mechanism of polyamine-mediated injury to the cardiac myocytes isolated from neonatal rat hearts. The myocytes, cultured in Dulbecco's minimal essential medium-1% foetal calf serum (FBS), were exposed to spermidine or spermine. The toxicity to myocytes was determined by (a) increased release of creatine kinase (CPK) into the media and (b) decline in cell viability or functional activity. Spermidine, above 10 mum, increased the release of CPK into media, decreased cell viability and decreased the functional activity of the myocytes. The FBS exhibited polyamine oxidase activity and semicarbazide-sensitive amine oxidase activity. Aminoguanidine, MDL72,527 or semicarbazide, are the inhibitors of amine oxidases, polyamine oxidase (PAO) and semicarbazide-sensitive amine oxidase (SSAO), respectively. The addition of these inhibitors to the medium protected the myocytes from spermidine toxicity. To determine whether myocyte PAO is involved in polyamine toxicity, we used horse serum that contained high SSAO activity and negligible PAO activity. The myocyte extracts had negligible SSAO activity but high PAO activity. When myocytes were cultured in horse serum in lieu of FBS, spermine caused toxicity at above 100 mum. In horse serum, MDL72,527 and semicarbazide protected the myocytes from spermine toxicity. These observations show that extracellular amine oxidases and myocyte PAO are significant in mediation of polyamine toxicity.

Differential induction of polyamine oxidase activity in liver and heart of iron-overloaded rats.

The present study was undertaken to investigate the effect of iron dextran treatment on polyamine oxidase (PAO) activity, iron accumulation, and lipid peroxidation in livers and hearts of rats. PAO catalyzes oxidative deamination of polyamines, the cellular aliphatic cations. This reaction produces highly toxic hydrogen peroxide, 3-acetamidopropanal, and precursors of higher polyamines. The rats were given iron dextran daily for 7 d. In iron-dextran-treated rats, a marked increase in the hepatic level of iron was associated with enhanced lipid peroxidation and increased PAO activity. Though iron accumulation and lipid peroxidation in the iron-treated rats increased significantly in the heart, PAO activity remained unchanged. The paraffin sections of livers stained with Perls iron stain showed the presence of iron in macrophages and hepatocytes. The sections of hearts showed iron deposits only in macrophages, while myocytes showed no iron staining. These results show that although iron dextran treatment results in accumulation of iron in both liver and heart, it induces PAO activity only in liver. The significance of increased PAO activity in lipid peroxidation and fibrosis in iron-mediated injury is discussed.

RAS gene mutations in Chinese leukaemia patients and members of a family with high incidence of leukaemia.

We investigated mutations of N-RAS and K-RAS by using polymerase chain reaction (PCR)-oligonucleotide hybridization techniques in 40 cases of Chinese leukaemia patients and 17 presently healthy members of a family with high incidence of acute myeloid leukaemia. The results showed only two patients carried the mutation in codon 12 of N-RAS. Strikingly, however, in both cases the malignancies involved lymphoid lineage. There was no hereditary RAS mutation in the members of the remarkable family.