Synthesis of dandelion-like TiO_2 microspheres as anode materials for lithium ion batteries with enhanced rate capacity and cyclic performances

Dandelion-like TiO2 microspheres consisting of numerous rutile single-crystalline nanorods were synthesized for the first time by a hydrothermal method. Their crystal structure, morphology and electrochemical properties were characterized by X-ray diffraction （XRD）, scanning electron microscopy （SEM）, transmission electron microscopy （TEM）, and galvanostatic charge and discharge tests. The results show that the synthesized TiO2 microspheres exhibit good rate and cycle performances as anode materials of lithium ion batteries. It can be found that the dandelion-like structure provides a larger specific surface area and the single-crystalline nanorod provides a stable structure and fast pathways for electron and lithium ion transport, which contribute to the rate and cycle performances of the battery.

Silencing Bmi-1 enhances the senescence and decreases the metastasis of human gastric cancer cells

AIM:To evaluate the impact of Bmi-1 on cell senescence and metastasis of human gastric cancer cell line BGC823.METHODS:Two pairs of complementary small hairpin RNA(shRNA)oligonucleotides targeting the Bmi-1gene were designed,synthesized,annealed and cloned into the pRNAT-U6.2 vector.After DNA sequencing to verify the correct insertion of the shRNA sequences,the recombinant plasmids were transfected into BGC823 cells.The expression of Bmi-1 mRNA and protein was examined by reverse transcription-polymerase chain reaction(RT-PCR)and Western blotting.The effects of Bmi-1 knockdown on cell senescence and metastasis were determined by theβ-Gal activity assay and Boyden chamber assay,respectively.RESULTS:The double-stranded oligonucleotide fragments of Bmi-1 short interfering RNA(siRNA)cloned into pRNAT-U6.2 vector conformed to the inserted sequence.RT-PCR and Western blotting indicated that the expression levels of Bmi-1 gene mRNA and protein were markedly decreased in transfected BGC823 cells with pRNAT-U6.2-si1104 and pRNATU6.2-si1356,especially in transfected BGC823 cells with pRNAT-U6.2-si1104,compared with two control groups(empty vector and blank group).In particular,Bmi-1 protein expression was almost completely abolished in cells transfected with the recombinant vector harboring shRNA targeting the sequence GGAGGAGGTGAATGATAAA(nt1104-1122).Compared with untransfected cells and cells transfected with the empty vector,the mean percentage of senescent cells increased and the number of cells passing through the Matrigel decreased in cells transfected with the recombinant vectors.CONCLUSION:Silencing Bmi-1 by RNA interference can increase the senescent cell rate and effectively reduce the metastasis of gastric cancer cells.

Therapeutic effect of autologous concentrated growth factor on lower-extremity chronic refractory wounds:A case report

BACKGROUND Management of chronic refractory wounds is one of the toughest clinical challenges for surgeons.Because of poor blood supply,less tissue coverage,and easy exposure,the lower leg is a common site for chronic refractory wounds.The current therapeutic regimens often lead to prolonged hospital stay and higher healthcare costs.Concentrated growth factor(CGF)is a novel blood extract that contains various growth factors,platelets,and fibrins to promote wound healing process.However,there has been little research reported on the treatment of lower extremity wounds with CGF.CASE SUMMARY A 37-year-old man,without any past medical history,presented an ulcerated chronic wound on his right lower leg.The skin defect exhibited clear boundaries,with a size of 2.0 cm×3.5 cm.The depth of wound was up to the layer of deep fascia.Staphylococcus aureus was detected by bacterial culture.The final diagnosis was right lower extremity ulcers with infection.Cefathiamidine,silver sulfadiazine,and mupirocin cream were applied to control the infection.CGF gel was prepared from the patient’s blood sample,and was used to cover the wound after thorough debridement.The skin wound was successfully healed after three times of CGF treatment.CONCLUSION CGF displays an excellent wound healing promoting effect in patients with lowerextremity chronic refractory wounds.