Magnetic ferrite nanoparticles (MFNPs) have great application potential in biomedical fields such as magnetic resonance imaging, targeted drugs, magnetothermal therapy and gene delivery. MFNPs can migrate under the action of a magnetic field and target specific cells or tissues. However, to apply MFNPs to organisms, further modifications on the surface of MFNPs are required. In this paper, the common modification methods of MFNPs are reviewed, their applications in medical fields such as bioimaging, medical detection, and biotherapy are summarized, and the future application directions of MFNPs are further prospected.
Ferric Compounds ; Magnetic Resonance Imaging/methods* ; Magnetics ; Magnetite Nanoparticles/therapeutic use* ; Nanoparticles

In this study, we improved the culture method of mouse hippocampal primary microglia to obtain hippocampal ramified microglia with high activity and purity, which were resemble to the resting status of normal microglia in healthy brain in vivo. Hippocampal tissue was excised from 2-4-week-old SPF C57BL/6J mice and cut into pieces after PBS perfusion, and then manually dissociated into the single-cell suspension by using Miltenyi Biotec's Adult Brain Dissociation Kit. The tissue fragments such as myelin in the supernatant were removed by debris removal solution in the kit. The cell suspension was incubated with CD11b immunomagnetic beads for 15 min at 4 °C. To obtain high-purity microglia, we used two consecutive cell-sorting steps by magnetic activated cell sorting (MACS). After centrifugation, the cells were resuspended and seeded in a 24-well culture plate. The primary microglia were cultured with complete medium (CM) or TIC medium (a serum-free medium with TGF-β, IL-34 and cholesterol as the main nutritional components) for 4 days, and then were used for further experiments. The results showed that: (1) The cell viability was (56.03 ± 2.10)% by manual dissociation of hippocampus; (2) Compared with immunopanning, two-step MACS sorting allowed for efficient enrichment of microglia with higher purity of (86.20 ± 0.68)%; (3) After being incubated in TIC medium for 4 d, microglia exhibited branching, quiescent morphology; (4) The results from qRT-PCR assay showed that the levels of TNF-α, IL-1β and CCL2 mRNA in TIC cultured-microglia were similar to freshly isolated microglia, while those were much higher in CM cultured-microglia after incubation for 4 d and 7 d (P < 0.05). Taken together, compared to the conventional approaches, this modified protocol of mouse hippocampal primary microglia culture by using MACS and TIC medium enables the increased yield and purity of microglia in the quiescent state, which is similar to normal ramified microglia in healthy brain in vivo.
Animals ; Cell Culture Techniques ; methods ; Cell Separation ; methods ; Cells, Cultured ; Hippocampus ; Magnetics ; Mice ; Mice, Inbred C57BL ; Microglia ; cytology

BACKGROUNDTraditional Chinese medicine wogonin plays an important role in the treatment of leukemia. Recently, the application of drug-coated magnetic nanoparticles (MNPs) to increase water solubility of the drug and to enhance its chemotherapeutic efficiency has attracted much attention. Drugs coated with MNPs are becoming a promising way for better leukemia treatment. This study aimed to assess the possible molecular mechanisms of wogonin-coated MNP-Fe3O4 (Wog-MNPs-Fe3O4) as an antileukemia agent.

METHODSAfter incubated for 48 h, the antiproliferative effects of MNPs, wogonin, or Wog-MNPs-Fe3O4on K562/A02 cells were determined by methyl thiazolyl tetrazolium (MTT) assay. The apoptotic rates of K562/A02 cells treated with either wogonin or Wog-MNPs-Fe3O4were determined by flow cytometer (FCM) assay. The cell cycle arrest in K562/A02 cells was determined by FCM assay. The elementary molecular mechanisms of these phenomena were explored by Western blot and reverse transcriptase polymerase chain reaction (RT-PCR).

RESULTSWith cell viabilities ranging from 98.76% to 101.43%, MNP-Fe3O4was nontoxic to the cell line. Meanwhile, the wogonin and Wog-MNPs-Fe3O4had little effects on normal human embryonic lung fibroblast cells. The cell viabilities of the Wog-MNPs-Fe3O4group (28.64-68.36%) were significantly lower than those of the wogonin group (35.53-97.28%) in a dose-dependent manner in 48 h (P < 0.001). The apoptotic rate of K562/A02 cells was significantly improved in 50 μmol/L Wog-MNPs-Fe3O4group (34.28%) compared with that in 50 μmol/L wogonin group (23.46%; P< 0.001). Compared with those of the 25 and 50 μmol/L wogonin groups, the ratios of G0/G1-phase K562/A02 cells were significantly higher in the 25 and 50 μmol/L Wog-MNPs-Fe3O4groups (all P< 0.001). The mRNA and protein expression levels of the p21 and p27 in the K562/A02 cells were also significantly higher in the Wog-MNPs-Fe3O4group compared with those of the wogonin group (all P< 0.001).

CONCLUSIONSThis study demonstrated that MNPs were the effective drug delivery vehicles to deliver wogonin to the leukemia cells. Through increasing cells arrested at G0/G1-phase and inducing apoptosis of K562/A02 cells, MNPs could enhance the therapeutic effects of wogonin on leukemia cells. These findings indicated that MNPs loaded with wogonin could provide a promising way for better leukemia treatment.

Apoptosis ; drug effects ; Cell Cycle ; drug effects ; Cell Line, Tumor ; Cell Proliferation ; drug effects ; Cell Survival ; drug effects ; Drug Delivery Systems ; methods ; Drug Resistance, Multiple ; Drugs, Chinese Herbal ; chemistry ; pharmacology ; Flavanones ; chemistry ; pharmacology ; Humans ; K562 Cells ; Magnetics ; Nanoparticles ; chemistry

The magnamosis device for stage-one repair of the rectovaginal tistula consists of two arc magnets. Drawing the interrupting thread along the fistula margin via the vaginal side, and pulling the string to arrange the magnets at the fistula base along the long axis of the vagina, we made the magnamosis device automatically clipped to seal the fistula. After removing the threads we kept the device for 2-4 weeks till the natural detachment of it when the compressed tissue in between healed after vascular necrosis. This device utilizing the unique ability of magnamosis to fulfill anastomosis under inflammatory infected state reduces the current high relapse rate and colostomy drawbacks of the conventional rectovaginal neoplasty.
Female ; Gynecologic Surgical Procedures ; instrumentation ; methods ; Humans ; Magnetics ; Magnets ; Pressure ; Rectovaginal Fistula ; surgery ; Wound Healing

This study was aimed to improve the sensitivity of magnetic induction phase shift detection system for cerebral hemorrhage. In the study, a cerebral hemorrhage model with 13 rabbits was established by injection of autologous blood and the cerebral hemorrhage was detected by utilizing magnetic induction phase shift spectroscopy (MIPSS) detection method under the feature band. Sixty five groups of phase shift spectroscopy data were obtained. According to the characteristics of cerebral hemorrhage phase shift spectroscopy under the feature hand, an effective method, B-F distribution, to diagnose the severity of cerebral hemorrhage was designed. The results showed that using MIPSS detection method under feature band, the phase shift obviously growed with increase of injection volume of autologous blood, and the phase shift induced by a 3-mL injection reached -7.750 3 degrees ± 1.420 4 degrees. B-F distribution could effectively diagnose the severity of cerebral hemorrhage. It can be concluded that the sensitivity of the cerebral hemorrhage magnetic induction detection system is improved by one order of magnitude with the MIPSS detection method under the feature band.
Animals ; Cerebral Hemorrhage ; diagnosis ; Magnetic Phenomena ; Magnetics ; Rabbits ; Spectrum Analysis ; methods

A new anastomat for digestive tract operations, based on the magnetic compressive technique and mechanical transmission mechanism, is composed of a removable head and a reusable body. The head includes two parts: the proximal end can be fixed to the body, and the distal end could be used for performing a purse string suture. The procedure of anastomosis is similar to that of the stapler, and the anastomoses is established using a pair of magnetic rings. The instrument makes magnamosis more simple and feasible, and it would facilitate the clinical application. The body of the anastomat is reusable and the head could be replaced according to the clinical scenarios, these could reduce the medical cost. The magnetic rings would be excreted with the feces, and there is no foreign body response at last.
Anastomosis, Surgical ; instrumentation ; methods ; Gastrointestinal Tract ; surgery ; Humans ; Magnetics

OBJECTIVETo explore the clinical effect of combination of acupressure and magnetic sticker on the quality of life (QOL) including appetite, defecation, and sleep in patients with advanced gastroenteric tumor.

METHODSTotally 147 patients with advanced gastroenteric tumor were assigned to 4 groups according to different treatment methods, i.e., the supportive treatment group (A, 20 cases), the acupressure treatment group (B, 41 cases), the magnetic sticker treatment group (C, 40 cases), and a combination of acupressure and magnetic sticker treatment group (D, 46 cases). They were respectively treated with different methods, supportive treatment for group A, acupressure for group B, magnetic sticker for group C, and a combination of acupressure and magnetic sticker for group D. The scores of food intake, defecation frequency, sleep time, Karnofsky, and QOL were compared before treatment and at day 14 after treatment.

RESULTSAfter treatment, the scores of food intake, defecation frequency, and sleep time were obviously improved in B, C and D groups (P < 0.01). There was statistical difference between group D and group A (P < 0.01). In addition, in comparison with A group, both Karnofsky score and QOL score increased in B, C and D groups (P < 0.01).

CONCLUSIONThe assisted therapy of the combination of acupressure and magnetic sticker could ameliorate QOL such as the digestive functions and sleep in patients with advanced gastroenteric tumor.

Acupressure ; methods ; Adult ; Aged ; Aged, 80 and over ; Female ; Gastrointestinal Neoplasms ; therapy ; Humans ; Magnetics ; Male ; Middle Aged ; Quality of Life ; Treatment Outcome

Magnetic compression anastomosis can compress tissues together and restore the continuity. Magnetic compression anastomosis mainly experienced three stages: magnetic ring, magnetic ring and column, and smart self-assembling magnets for endoscopy (SAMSEN). Nowadays, the magnetic compression anastomosis has been applied in vascular and different digestive tract surgeries, especially for complex surgery, such as anastomotic stenosis of biliary ducts after liver transplantation or congenital esophageal stenosis. Although only case reports are available at present, the advantages of the magnetic compression anastomosis includes lower cost, simplicity, individualization, good efficacy, safety, and minimally invasiveness. We are building a better technical platform to make magnetic compression anastomosis more advanced and popularized.
Anastomosis, Surgical ; methods ; Digestive System Surgical Procedures ; methods ; Humans ; Magnetics

Monoclonal antibody (mAb, NVRQS-DON) against deoxynivalenol (DON) was prepared. DON-Ag coated enzyme linked immunosorbent assay (ELISA) and DON-Ab coated ELISA were prepared by coating the DON-BSA and DON mAb. Quantitative DON calculation ranged from 50 to 4,000 ng/mL for DON-Ab coated ELISA and from 25 to 500 ng/mL for DON-Ag coated ELISA. 50% of inhibitory concentration values of DON, HT-2, 15-acetyl-DON, and nivalenol were 23.44, 22,545, 5,518 and 5,976 ng/mL based on the DON-Ab coated ELISA. Cross-reactivity levels of the mAb to HT-2, 15-acetyl-DON, and nivalenol were 0.1, 0.42, and 0.40%. The intra- and interassay precision coefficient variation (CV) were both <10%. In the mAb-coated ELISA, mean DON recovery rates in animal feed (0 to 1,000 microg/kg) ranged from 68.34 to 95.49% (CV; 4.10 to 13.38%). DON in a buffer solution (250, 500 and 1,000 ng/mL) was isolated using 300 microg of NVRQS-DON and 3 mg of magnetic nanoparticles (MNPs). The mean recovery rates of DON using this mAb-MNP system were 75.2, 96.9, and 88.1% in a buffer solution spiked with DON (250, 500, and 1,000 ng/mL). Conclusively we developed competitive ELISAs for detecting DON in animal feed and created a new tool for DON extraction using mAb-coupled MNPs.
Animal Feed/analysis ; Animals ; Antibodies, Fungal/analysis ; Antibodies, Monoclonal/analysis ; Chemistry Techniques, Analytical/*methods ; Enzyme-Linked Immunosorbent Assay/*methods/veterinary ; Female ; Food Contamination/*analysis ; Fusarium/immunology ; Imidazoles/chemistry ; Magnetics/methods ; Mice ; Mice, Inbred BALB C ; Mycotoxins/*analysis/chemistry ; Nanoparticles/chemistry ; Ovalbumin/chemistry ; Trichothecenes/*analysis/chemistry

OBJECTIVEApplication of matrix assisted laser desorption ionization time of flight mass spectrometry enhancement (MALDI-TOF-MS) combined with WCX nanometer magnetic bead technique, screening of the serum biomarkers in pituitary adenoma, to establish a serum protein fingerprint classification decision tree.

METHODSAnalyse the serum samples of 40 cases of pituitary adenoma and 60 cases of healthy adult and find the different protein peaks, then to establish the diagnosis model and the classification decision tree of pituitary adenomas.

RESULTSA total of 42 differences in protein peaks were identified in the experimental and control group (P < 0.01). The diagnosis model of pituitary adenomas was established by three protein peaks (3382.0, 4601.9, 9191.2). The model could screen the pituitary adenoma out of the normal population. The sensitivity was 90.00% and the specificity was 88.30%. By the double blind experimental validation, the model could diagnose the pituitary adenoma and the sensitivity was 88%, the specificity was 83.30%.

CONCLUSIONSignificantly different protein peaks can be screened out between pituitary adenoma cases and healthy controls using MALDI-TOF-MS combined with WCX technique, and these protein peaks may be used as a pituitary adenoma detection, follow-up indicator.

Adult ; Aged ; Blood Proteins ; analysis ; Case-Control Studies ; Female ; Humans ; Magnetics ; Male ; Middle Aged ; Pituitary Neoplasms ; blood ; diagnosis ; Proteomics ; Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization ; methods ; Young Adult