Magnetic silica micro-spheres is a kind of novel functional materials, which is expected to be applied to targeted drug delivery, immunomagnetic beads, separation of nucleic acid and protein, immobilization of enzymes and isolation and purification of natural products in biomedicine. This review describes the methods of synthesis, surface modification and applications of magnetic silica micro-spheres, which focus on the various strategies in synthesis with core-shell and mosaic structure, sol-gel method, liquid phase deposition, self-assembly technique and micro-emulsion method. Finally, foregroud and prospect of the research are also discussed.

Objective To separate human γ-tubulin ring complexes (γTuRC) .Methods Cell lysates prepared from 293FT cells were separated using gel filtration chromatography .Then, the eluate fractions containing γTuRC or γ-tubulin small complexes (γTuSC ) were determined by immunoblotting .Results As the constitutive components of γTuRC,γ-tubulin,γ-tubulin complex protein 2 (GCP2), GCP3 and GCP4 were eluted and enriched in the fourth fraction .The molecular mass of eluates in the fourth fraction was about 2000 ×10 3 .Following γTuRC, the constitutive components ofγTuSC including γ-tubulin, GCP2 and GCP3 were eluted and enriched in the fourteenth fraction .The molecular mass of eluates in the fourteenth fraction was about 310 ×10 3 .Unassembled free components were washed out in the eighteenth and subsequent fractions .γTuRC could be detected in the corresponding fractions by negative-PAGE separation .ConclusionγTuRC and γTuSC were successfully separated from the unassembled free components in the fourth ( 4#) and fourteenth (14#) eluted fraction, respectively.The eluates containing ofγTuRC orγTuSC can be used for microtubule assembly research.

Objective To investigate the role of Astragahs in alleviating adhesion of neutrophils to HK-2 cells induced by postasphyxial-serum of neonate and its signal transduction mechanism. MethodsHK-2 cells were used as target cell. Control group, asphyxia group, Astragalus group were divided in the experiment. The 20％ (volume fraction) postasphyxial-serum was used as attacking factor. The following indicators were detected: cellular morphology and neutrophils adhesion were observed with inverted microscope. The activity of myeloperoxidase (MPO) in the cell suspension were determined by biochemistry assay as the indicator for adhesion of neutrophils to HK-2. Intercellular adhesion molecule-1(ICAM-1) were examined by flow eytometer. ResultsThe neutrophils numbers (MPO activity) and ICAM-1 expression in asphyxia group were higher than that of the control group, but dramatically decreased in Astragalus group (P < 0.05). ConclusionsThese data demonstrated that Astragalus could alleviate the adhesion of neutrophils from neonate with asphyxia to HK-2 and it' s intracellular signal transduction mechanism is presumably involved in the inhibition of ICAM-1 expression on HK-2 cellular membrane.

Objective To investigate the effects of osthole on neural stem cells ( NSCs) differentiation and explore the potential mechanism. Methods Brain-derived NSCs from newborn mice were isolated and cultured in vitro and determined by immunofluorescence. The P5 generations of NSCs were placed in culture solution with osthole at concentrations of (0,10,50, 100 μmol·L-1 ) . The neuron, astrocyte and oligodendroglia cell differentiation were determined by immunofluorescence. The mRNA expression of Notch 1 and its target genes Mash 1 and Neurogenin 2 were assessed by RT-PCR. Results The neurosphere displayed Nestin and Sox 2-postive by immunofluorescence, suggesting that the cultured cells were NSCs. Osthole promoted NSCs differentiating into more neuron(P<0. 01) and oligodendrocyte(P<0. 05), but not astrocyte. Meanwhile, osthole significantly reduced the mRNA expression of Notch 1(P<0. 01) and increased Ngn 2(P<0. 01)at the dose of 100 μmol·L-1. Conclusion Osthole enhances NSCs differentiating into more neuron and oligodendrocyte via probablly inhibiting Notch signal pathway.

Magnetic chitosan (CS) nano-spheres were prepared by the modified suspension cross-linking technique. The results demonstrated that the magnetic drug nano-spheres are mainly spherical in form with a size of 200 to 800 nm, and show good magnetic responsivity. Here, Doxorubicin was used as exam drug. Glutaraldehyde connects Doxorubicin to CS by the chemical bond (-N = C-), and the drug content is in range of 1% to 15% (w/w). The chemical bond is broken depending on pH, so pH is the important factor for the release of doxorubicin. The doxorubicin release was 22.0%, 13.4%, and 4.1% in the space of 7d, when pH was 1, 2, 4. So the nano-spheres are pH-sensitive magnetic targeting drug micro-spheres.
Chitosan ; chemistry ; Doxorubicin ; administration & dosage ; Drug Carriers ; chemical synthesis ; Drug Delivery Systems ; methods ; Magnetics ; Nanospheres ; chemistry

Objective:To explore the efficacy of tracheotomy and nasal intubation in airways management in treatment of patients with respiratory failure caused by severe tetanus.Methods:A respective case series study was conducted to analyze the data of 92 patients with respiratory failure caused by severe tetanus admitted to Jiangxi Chest Hospital from January 2012 to December 2019. There were 60 males and 32 females, aged 23-81 years [(47.5±14.1)years]. Overall 43 patients underwent tracheotomy (tracheotomy group), and 49 patients underwent nasal intubation (nasal intubation group). The blood gas related indexes (PaO 2, PaCO 2), catheter retention time, incidence of complications such as airway bleeding, nasosinusitis, catheter blockage and ventilator-associated pneumonia (VAP), and clinical outcome were compared between the two groups. Results:After mechanical ventilation, the PaO 2 and PaCO 2 in both groups were significantly improved ( P<0.01), with no significant difference between groups ( P>0.05). Both groups were similar regarding the catheter indwelling time, catheter blockage, airway bleeding and nasosinusitis ( P>0.05). The incidences of VAP and catheter blockage after extubation in tracheotomy group [12%(5/43), 12%(5/43)] were significantly different from those in nasal intubation group [0%(0/49), 31%(15/49)] ( P<0.05). There were 3 deaths in each group, with the mortality rate of 7% (3/43) in tracheotomy group and of 6% (3/49) in nasal intubation group ( P>0.05). Both groups of live tetanus patients were cured. After 3-month follow-up, the tetanus was cured in the two groups. Conclusions:The tracheotomy and transnasal tracheal intubation are optional for severe tetanus patients with respiratory failure. The former has airway and tissue trauma, but it is convenient for mechanical ventilation management, especially indicated for patients with severe convulsions, angular arch reflexes, poor sedation, and continuous application of muscle relaxants. Nasal intubation is relatively non-invasive, simple and fast method, but the prevention and monitoring of VAP requires higher requirements.

Objective:To evaluated the options in selection of surgical procedures for treatment of the patients suffering from diabetic feet with chronic refractory wounds.Methods:From January 2020 to June 2021, 23 patients with diabetic feet complicated with refractory wounds were treated in Department of Hand Surgery, Shunde Heping Surgical Hospital. The patients were 15 males and 8 females, aged 51-86 years old and with an average age of 65 years old. All the patients had Type-II diabetes for over 5 - 22 years. Average blood glucose of the patients was found at 15.6 mmol/L on admission. Free anterolateral thigh perforator flaps (ALTPF) were used for reconstruction of the wound of diabetic feet in 19 patients, 2 patients received vascular bypass surgery and 2 had amputations. Regular outpatient follow-up were conduct on all patients after surgery.Results:Follow-up time lasted for 8 to 30 months, 12 months in average. At the last follow-up, the donor and recipient sites healed well in the 19 patients who received flap reconstruction, without an infection, necrosis and wound recurrence. Pains were significantly relieved after the surgery in the 2 patients who received vascular bypass surgery, and wounds all healed well after symptomatic treatment and dressing change without recurrence of wounds at the last follow-up. Average Maryland score of foot function was 84 for the patients who had limb salvage, and 2 patients were in excellent and 19 in good at the last follow-up. The 2 patients who had amputation successfully survived through the perioperative period, and the wounds healed well at the last follow-up.Conclusion:The treatment is complicated in the patient suffering from diabetic foot with chronic refractory wounds due to factors such as advanced age, co-existing and complicated underlying diseases together with the complex wounds. Most patients can achieve good prognosis in wound treatment of free flap transfer or vascular bypass surgery. However, a limb salvage is recommended with caution for the patients who have severe infections and dry gangrene.