Alternative technique to save ischemic bowel segment in management of neonatal short bowel syndrome: A case report

BACKGROUND Congenital short bowel syndrome(SBS)associated with malrotation,gut volvulus and jejuno-ileal atresia is a very rare condition.It is a severe challenge for surgeons to preserve residual ischemic bowel segment in the management of short bowel syndrome,especially in neonates.CASE SUMMARY We report a newborn baby with gut malrotation associated with jejuno-ileal atresia,congenital SBS and jejunal volvulus.Hematemesis and abdominal distention were noted.At laparotomy,malrotation associated with jejuno-ileal atresia,congenital SBS and jenunal volvulus was confirmed.The total length of the small bowel was 63 cm with proximal jejunal bowel segment measuring 38 cm,including 18 cm necrotic segment below the Treitz’s ligament and 20 cm severe ischemic segment.The distal part of the small bowel was 25 cm in length and only about 0.8 cm in diameter.Ladd’s procedure,necrotic segment resection and end-to-back duodeno-ileal anastomosis were performed.The residual severe ischemic jejunum was preserved with single proximal stoma and distal end closure.Three months later,to restore the continuity of the isolated gut segment,end-to-end duodeno-jejunal and jejuno-ileal anastomosis was performed.The entire functional small bowel length increased to 80 cm.Intravenous fluid therapy and parenteral nutrition were discontinued on the 10th day postoperatively.Twelve months later,her body weight was 9.5 kg.CONCLUSION Isolation of severe ischemic bowel segment and staged anastomosis to restore the gut continuity for infants with SBS are safe and feasible.

Bio-compatibility and cytotoxicity studies of water-soluble CuInS_2-ZnS-AFP fluorescence probe in liver cancer cells

BACKGROUND： The oncogenesis of hepatocellular carcinoma（HCC） is not clear. The current methods of the pertinent studies are not precise and sensitive. The present study was to use liver cancer cell line to explore the bio-compatibility and cytotoxicity of ternary quantum dots（QDs） probe and to evaluate the possible application of QDs in HCC.METHODS： CuInS_2-ZnS-AFP fluorescence probe was designed and synthesized to label the liver cancer cell HepG 2. The cytotoxicity of CuInS_2-ZnS-AFP probe was evaluated by MTT experiments and flow cytometry. RESULTS： The labeling experiments indicated that CuInS_2-ZnS QDs conjugated with AFP antibody could enter HepG 2 cells effectively and emit intensive yellow fluorescence by ultraviolet excitation without changing cellular morphology. Toxicity tests suggested that the cytotoxicity of CuInS_2-ZnS-AFP probe was significantly lower than that of CdT e-ZnS-AFP probe（t test, F=0.8, T=-69.326, P〈0.001）. For CuInS_2-ZnS-AFP probe, timeeffect relationship was presented in intermediate concentration（〉20%） groups（P〈0.05） and dose-effect relationship was presented in almost all of the groups（P〈0.05）. CONCLUSION： CuInS_2-ZnS-AFP QDs probe had better biocompatibility and lower cytotoxicity compared with CdT e-ZnS-AFP probe, and could be used for imaging the living cells in vitro.

Au@SiO2 @CuInS2–ZnS/Anti-AFP fluorescent probe improves HCC cell labeling

Background: Clear tumor imaging is essential to the resection of hepatocellular carcinoma(HCC). This study aimed to create a novel biological probe to improve the HCC imaging. Methods: Au nano-flower particles and CuInS2 –Zn S core-shell quantum dots were synthesized by hydrothermal method. Au was coated with porous SiO2 and combined with anti-AFP antibody. HCC cell line HepG2 was used to evaluate the targeting efficacy of the probe, while flow cytometry and MTT assay were used to detect the cytotoxicity and bio-compatibility of the probe. Probes were subcutaneously injected to nude mice to explore light intensity and tissue penetration. Results: The fluorescence stability of the probe was maintained 100% for 24 h, and the brightness value was 4 times stronger than that of the corresponding CuInS2 –Zn S quantum dot. In the targeting experiment, the labeled HepG2 emitted yellow fluorescence. In the cytotoxicity experiments, MTT and flow cytometry results showed that the bio-compatibility of the probe was fine, the inhibition rate of HepG2 cell with 60% Cu-QDs/Anti-AFP probe and Au-QDs/Anti-AFP probe solution for 48 h were significantly different(86.3%±7.0% vs. 4.9%±1.3%, t = 19.745, P < 0.05), and the apoptosis rates were 83.3%±5.1% vs. 4.4%±0.8%( P < 0.001). In the animal experiment, the luminescence of the novel probe can penetrate the abdominal tissues of a mouse, stronger than that of CuInS2 –ZnS quantum dot. Conclusions: The Au@SiO2 @CuInS2 –ZnS/Anti-AFP probe can targetedly recognize and label HepG2 cells with good bio-compatibility and no toxicity, and the strong tissue penetrability of luminescence may be helpful to surgeons.

Synthesis of carbon-supported Pd/SnO_2 catalyst for highly selective hydrogenation of 2,4-difluoronitrobenzene

Halogenated anilines have a wide range of applications in the production of pharmaceuticals and agrochemical substances, and thus it is of great importance to develop highly active and selective catalysts for the hydrogenation of halogenated nitrobenzenes. We approach this challenge by probing noble metal/non-noble metal oxide nanoparticles（NPs） catalysts. Carbon-supported Pd/SnO2catalysts were synthesized by the chemical reduction method, and their catalytic activity was evaluated by the hydrogenation reaction of 2,4-difluoronitrobenzene（DFNB） to the corresponding 2,4-difluoroaniline（DFAN）, showing a remarkable synergistic effect of the Pd and SnO2 NPs. The as-prepared Pd/SnO2/C catalysts were characterized using TEM, XRD, H2 TPD and XPS techniques. Modifications to the electronic structure of the Pd atoms through the use of SnO2 led to the suppression of the hydrogenolysis of the C–F bond and the acceleration of nitrosobenzene（DFNSB） conversion and consequently, resulted in the inhibition of the formation of reactive by-products and may be responsible for the enhancements observed in selectivity.

Visible-light photoredox-mediated oxidation of N-methyl tertiaryamines under catalyst free conditions:Direct synthesis of methylene-bridged bis-1,3-dicarbonyl compounds

Mediated by visible light-induced photoredox catalysis and free of other catalysts, a new and efficient synthesis of methylene-bridged bis-l,3-dicarbonyl derivatives has been developed. A variety of N-methyl tertiaryamines and 1,3-dicarbonyl compounds were investigated in this reaction.