Role of 3D printing positioning guide in neurosurgery / 中华神经医学杂志

Objective:To explore the application value of individualized three-dimensional (3D) printing positioning guides in localization and resection of intracranial lesions.Methods:Fifteen patients with intracranial space occupying lesions underwent resection in our hospital from March 2021 to May 2021 were selected in our study. Brain images by CT and MRI as raw data were used to design individual positioning guides. The positioning guides were placed on the patient's skin before resection to mark the location and boundary of the lesions with a marker, and neuro-navigation was used to verify the accuracy. During the resection, the location of the lesions was identified through microscope by the surgeons. Postoperative CT and MRI were used to evaluate the lesion resection.Results:The individualized positioning guides of 15 patients fit the skin well, and the skin incision and bone window were designed to meet the surgical requirements. All surgeries were completed in one time, and the lesion tissues were successfully removed. During the surgeries, the skin incision was not adjusted for secondary expansion. Brain MRI reexamination within 48 h of surgery showed that the lesions of 11 patients with tumors were removed satisfactorily (total resection in 9 and subtotal resection in 2); brain CT reexamination within 12 h showed that the clearance rate of hematomas in 3 patients was above 80% and that in 1 patient was 70%. No patients had cerebrospinal fluid leakage, intracranial hematoma, intracranial infection or other serious complications. All patients recovered well during the 1-3 months of outpatient/telephone follow-up.Conclusion:The positioning method with personalized 3D printing guides is simple and convenient, enjoying accurate positioning results, which can assist the clinicians to optimize the preoperative planning, optimize the surgical incision design, and is worthy of promotion and application in primary hospitals.

Clonal evolution and clinical significance of trisomy 8 in acquired bone marrow failure / 中华血液学杂志

Objective@#To analyze clonal evolution and clinical significance of trisomy 8 in patients with acquired bone marrow failure.@*Methods@#The clinical data of 63 patients with acquired bone marrow failure accompanied with isolated trisomy 8 (+8) from June 2011 to September 2018 were analyzed retrospectively, the clonal evolution patterns and relationship with immmunosuppressive therapy were summarized.@*Results@#Totally 24 male and 39 female patients were enrolled, including 39 patients with aplastic anemia (AA) and 24 patients with relatively low-risk myelodysplastic syndrome (MDS) . Mean size of+8 clone in MDS patients[65% (15%-100%) ]was higher than that of AA patients[25% (4.8%-100%) , z=3.48, P=0.001]. The patients were was divided into three groups (<30%, 30%-<50%,and ≥50%) according to the proportion of+8 clone. There was significant difference among the three groups between AA[<30%:55.6% (20/36) ; 30-50%: 22.2% (8/36) ; ≥50%22.2% (8/36) ]and MDS patients[<30%:19.0% (4/21) ; 30%-<50%:19.0% (4/21) ; ≥50%61.9% (13/21) ] (P=0.007) . The proportion of AA patients with+8 clone <30% was significantly higher than that of MDS patients (P=0.002) ; and the proportion of AA patients with+8 clone ≥50%was significantly lower than that of MDS patients (P=0.002) . The median age of AA and MDS patients was respectively 28 (7-61) years old and 48.5 (16-72) years old. Moreover, there was no correlation between age and+8 clone size in AA or MDS (rs=0.109, P=0.125; rs=-0.022, P=0.924, respectively) . There was statistical difference in total iron binding capacity, transferrin and erythropoietin between high and low clone group of AA patients (P=0.016, P=0.046, P=0.012, respectively) , but no significant difference in MDS patients. The immunosuppressive therapy (IST) efficacy of AA and MDS patients was respectively 66.7% and 43.8% (P=0.125) . Comparing with initial clone size (27.3%) , the +8 clone size (45%) of AA patients was increased 1-2 year after IST, but no statistical difference (z=0.83, P=0.272) . Consistently, there was no significant change between initial clone size (72.5%) and 1-2 year clone size (70.5%) after IST in MDS patients. There was no significant difference in IST efficient rate between +8 clone size expansion and decline group of in AA patients at 0.5-<1, 1-2 and>2 years after IST. We found four dynamic evolution patterns of +8 clone, which were clone persistence (45%) , clone disappearance (30%) , clone emergence (10%) and clone recurrence (15%) .@*Conclusions@#AA patients had a low clone burden, while MDS patients had a high burden of +8 clone. The +8 clone of AA patients didn’t significantly expanded after IST, and the changes of +8 clone also had no effect on IST response.

Research on the microstructure of antibacterial nanocomposite membrane and it's biocompatibility as a guided bone regeneration membrane / 华西口腔医学杂志

<p><b>OBJECTIVE</b>To study the microstructure of the Ag-nHA-nTiO2/PA66 membrane and investigate its biocompatibility.</p><p><b>METHODS</b>The microstructure of Ag-nHA-nTiO2PA66 membrane and e-polytetra fluoroethylene (e-PTFE) membrane were observed by light microscope and scanning electron microscope(SEM). MG63 osteoblast-like cells were cultured on the two kinds of membrane and blank group. The cell proliferation was checked by methyl thiazolyl tetrazolium (MTT) method and alkaline phosphatase (ALP) activity was detected by enzyme linked immunosorbent assay (ELISA). The adhesion and proliferation of the cells on the two kinds of membrane was observed by SEM.</p><p><b>RESULTS</b>The Ag-nHA-nTiO2/PA66 membrane was composed of the obverse face and the opposite face. The obverse face was porous and the opposite face was smooth. Microstructures of the obverse and the opposite face of the e-PTFE membrane were same. The e-PTFE membrane showed many tiny lined cracks in elliptic structure. MTT assay and ALP measurement showed that there were no significant difference between each of the two membrane groups and the blank (P > 0.05). The adhesion and proliferation of cells on the Ag-nHA-nTiO2/PA66 membrane were better than the e-PTFE membrane.</p><p><b>CONCLUSION</b>Ag-nHA-nTiO2/PA66 membrane has no negative effects on the growth of osteoblast-like cells. Ag-nHA-nTiO/PA66 membrane is biocompatible and its microstructure is appropriate as a guided bone regeneration materials.</p>

Effect of APE1/Ref-1 on differentiation of peripheral blood mononuclear cells into osteoclast-like cells / 重庆医学

Objective To investigate the effect of APE1 on differentiation of peripheral blood mononuclear cells into osteoclast-like cells(OCL) which induced by macrophage colony stimulating factor (RANKL) and macrophage colony stimulating factor (M-CSF) .Methods Human peripheral blood mononuclear cells (PBMCs) were collected by density gradient separation ;Constructed APE1 siRNA expression vector Ad5v-APE1 siRNA was used to transfect PBMCs .Tartrate-resistant acid phosphatase (TRAP) method was conducted to identify the cells ,the expression level of APE1 was detected by Western blot ,the mRNA expression levels of Cathepsin K(CK) and V-ATPase were detected by RT-PCR .Results PBMCs transfected with APE1 siRNA had significantly lower protein expression of APE1 than untransfected cells (P< 0 .05) ;PBMCs could differentiate into OCL under the stimulation of RANKL and M-CSF ,the mRNA expression levels of CK and V-ATPase increased ;After APE1 siRNA treatment ,the number of OCL was reduced and the levels of CK and V-ATPase mRNA decreased .Conclusion PBMCs can differentiate into a large number of OCL induced by RANKL and M-CSF ,APE1 siRNA significantly inhibited differentiation of PBMCs into osteoclast-like cells , APE1 may be involved in the regulation of osteoclast-like differentiation process .

The correlation study between spatial memory and hippocampal long term potentiation in rats / 中华行为医学与脑科学杂志

ObjectiveTo investigate the correlation of hippocampal synaptic plasticity with spatial learning and memory under normal and pathological condition,and provide experimental evidence for the coincidence of hippocampal late-phase long-term potentiation (L-LTP) and behavioral experiments.Methods 38 SD rats were randomly divided into two groups,control and AD model.First,Morris water maze was used to test the ability of spatial learning and memory of rats.The escape latencies for rats to search for an underwater platform in 5 days of navigation tests and the swimming time percentage in target qtuadrant on the 6th day after withdrawing the platform in probe trails were recorded.Then,in vivo hippocampus L-LTP of field excitatory postsynaptic potential (fEPSP)in CA1 region was recorded after delivering high frequency stimulation (HFS).ResultsBilateral intrahippocampal injection of 4 nmol amyloid β peptide ( Aβ 25-35 ) significantly impaired spatial learning and memory of rats in water maze tests,as well as in vivo hippocampal L-LTP.In control group,there was a significant negative correlation between the amplitude of fEPSP and the escape latency ( r =-0.8306,P ＜ 0.01 ) and a significant positive correlation between the amplitude of fEPSP and the swimming time percentage in target quadrant ( r=0.7709,P＜0.01 ).In AD model group,similar correlations were found,with a correlation coefficient of r =-0.7675 (P ＜0.01 ) and r =0.8049 (P ＜ 0.01 ),respectively.When putting all data from the two groups together,the hippocampal L-LTP was more correlated with escape latency ( r =-0.9124,P ＜ 0.01 ) and swimming time percentage ( r=0.9745,P＜0.01).ConclusionThere is very close correlation between the hippocampal L-LTP and the spatial learning and memory behavior in rats,suggesting that the hippocampal L-LTP may be involved in the electrophysiological mechanism of spatial learning and memory in rats,and the impairment of L-LTP could partly represent the deficits in cognitive function of animals.

Relationship between high-expressed TL1A and level of IFN-γ secreted by T cells in acute stage of Guillain-Barr(e) syndrome / 中华神经科杂志

Objective To probe the relationship between the expression of TL1A and the level of IFN-γ secreted by T cells in the acute stage of Guillain-Barre syndrome (GBS). Methods ① Six-week female Bal b/c mice were immunized by purified recombinant human soluble TNF-like molecular 1A (rhsTL1A) protein. The polyclonal antibody against rhsTL1A was identified by immunofluorescence using human umbilical vein epithelial cells (HUVEC). ② To detect the biologic activity of rhsTL1A, the peripheral blood mononuclear cells (PBMC) from the healthy donors were separated by Ficoll gradient centrifugation and were seeded on 96-well plates with medium containing 2 μg/ml PHA (control group), 2 μg/ml PHA + 25 ng/ml rhsTL1 A, 2 μg/ml PHA + 100 ng/ml rhsTL1A and 2 μg/ml PHA + 400 ng/ml rhsTLlA respectively. T cell proliferation assay was carried out using ~3H-TdR. ③ IFN-γ productions in the sera of the children with GBS in the acute stage were detected by ELISA. ④ The ratio of CD_3~+ TL1A~+ T cells to CD_3~+ T cells in the peripheral blood of the children with GBS in acute stage was detected with flow, cytometry. ⑤PBMC from the children in acute GBS were separated and cultured in the environment adding 2 μg/ml PHA and 400 ng/ml rhsTL1A in vitro. Then, the IFN-γ in the supernatant was determined by ELISA kit after 72 hours. Results ① hTL1A A expressed by eukaryotic HUVECs was recognized by rhsTL1 A polyclonal antiserum. ② The result of T cell proliferation assay showed that SI of 25 ng/ml rhTL1A, 100 ng/ml rhTL1A A and 400 ng/ml rhTL1A group was increased compared with control group. The SI of 2 μg/ml PHA +400 ng/ml rhsTL1 A group was the highest (2. 65) among them. ③ IFN-γ productions in the sera of the children with GBS in the acute stage ((102. 25±22. 17) pg/ml) were increased significantly compared with healthy control ((28.75 ± 1.31) pg/ml, t = 3. 309, P < 0. 05). ④ The ratio of CD_3~+ TL1A~+ T cells to CD_3~+ T cells in the peripheral blood of the children with GBS in acute stage (18.22%± 1.83%) was enhanced significantly compared with healthy control (5. 17% ±0. 48%, t = 6. 884, P < 0. 01). ⑤ PBMC both in healthy control and the acute GBS secreted more IFN-γ markedly ((43.56± 4.41) pg/ml and (180.64 ± 38.39) pg/ml) after being incubated in 2 μg/ml PHA and 400 ng/ml rhsTL1A (t =4. 523 and 2. 600, P <0. 01 and 0. 05 respectively). Moreover, PBMC in acute GBS secreted more IFN-γ, than that of the healthy group markedly (t = 3. 545, P < 0. 05). Conclusions ① The mouse antiserum recognizing rhsTL1A is successfully obtained. ② In this study, 400 ng/ml rhsTL1A promotes the proliferation of T cells activated by 2 μg/ml PHA, indicating that rhsTL1A has biological activity. ③ The expression of hTL1A of activated T cells in the peripheral blood of the children with acute GBS is up-regulated. These TL1A proteins promote the secretion of IFN-γ through binding to their receptors DR_3.

The experimental study of PDLLA/rhBMP-2 compound screws for internal fixation of mandibular fracture / 华西口腔医学杂志

<p><b>OBJECTIVE</b>To study the effect of poly D,L-lactic acid (PDLLA) screws with PDLLA-rhBMP compound on bone regeneration in the screw holes and fracture ends of dog mandibles.</p><p><b>METHODS</b>A self-control study was carried out in 4 dogs. PDLLA/rhBMP-2 compound screws were implanted to fix the mental fractures and PDLLA screws were used as control. The samples from mandibles were collected at 4, 8, 12, 16 weeks after implantation and observed by radiography and histology.</p><p><b>RESULTS</b>All dogs showed a greater degree of bone regeneration around PDLLA/rhBMP-2 screws than PDLLA ones and all fractures were fixed and healed well.</p><p><b>CONCLUSION</b>The PDLLA-rhBMP screw has a better effect of inducing osteogenesis than PDLLA screw, and is able to exert a good fixation to fracture.</p>

Study on injectable bioactive bone repairing material of nano-hydroxyapatite and polyamide-66 composite / 生物医学工程学杂志

The aim of this study was to evaluate the injectability, histocompatibility, function and other properties of the injectable bioactive bone repairing material of nano-hydroxyapatite and polyamide-66 (n-HA/PA66) composite. The XRD pattern, the relationship between the injectability and liquid-powder ratio, setting time and liquid-powder ratio, compressive strength and liquid-powder ratio were assessed. The size of the composite was determined to be 70 nm in length and 30 to 50 nm in width, and the molecular weight of polyamides-66 was 18000. The diameter of pores of the composite was about 200 to 400 micrometer. To evaluate the histocompatibility and function, 8 male dogs were studied with the injectable n-HA/PA66 composite implanted in the artificial defected alveolus of mandible on only one side to be compared with the intact alveolus on the other side. The specimens were taken at 4, 8, 12, 16 months after the implantation and the results were evaluated. The XRD pattern of the solidificated n-HA/PA66 composite was the same as the powdered n-HA/PA66 composite. The injectable n-HA/PA66 composite had a good injectability, 25 to 30 minutes setting time and about 37 MPa compressive strength when the liquid-powder ratio was 0.50. The healing of the gingiva was well at the implanted areas in all animals. The height of the repaired alveolar bone was obvious higher than that of the blank control. The earlier sign of ossification was histologically observed at 16 weeks after implantation. The injectable n-HA/PA66 composite has good biocompatibility and osteoconductive property. As an injectable material, with good maneuverability, it is useful for repairing irregular bone defects, especially in oral and maxillofacial surgery.