The pathogenesis of aplastic anemia(AA)is complex and associated with hematopoietic stem cell defect,abnormal bone marrow microenvironment,immune dysfunction,and somatic mutation,in which the immune mechanism plays an important role.This article reviews the pathogenesis of AA from the following aspects:regulatory T cell reduction,hematopoietic stem cell reduction caused by factor-related apoptosis/factor-related apoptosis ligand signaling pathway,aberrant target gene expression induced by inflammatory factor-stimulated microRNAs,and regulatory T cell dysfunction,so as to provide ideas and methods for clinical practice.

Currently, titanium alloys are widely used in the field of stomatology; however, owing to long-term exposure to a complex microbial environment, dental plaques easily form on the surface of the materials, affecting the use efficiency and the service life of the materials. The antibacterial titanium alloy is a new kind of titanium alloy with antimicrobials added through surface modification or overall modification. Based on the location of antibacterial agents in titanium alloy materials, antibacterial titanium alloys can be divided into coating and alloy types. The antibacterial effect of coated antibacterial titanium alloy is good, but the disadvantage is that most of the coatings are not wear-resistant. The widely-used antibacterial agent of the alloy type is metal elements, which can be evenly distributed in the alloy, and the antibacterial properties are stable and long-lasting. Based on whether antibacterial agents can be released, antibacterial titanium alloys can be further divided into active antibacterial and passive antibacterial types. Active antibacterial type titanium alloys can release loaded antibacterial agents, and the antibacterial effect is more obvious, but the release duration of antibacterial agents is relatively short. Passive antibacterial titanium alloys exhibit an antibacterial effect by contact sterilization or inhibition of bacterial adhesion instead of releasing antibacterial agents. The antibacterial titanium alloy can inhibit the adhesion of bacteria on the surface of the material and prolong the service life of oral orthodontic appliances, implants and titanium plates. Moreover, the mechanical properties of the titanium alloy after antibacterial modification are not significantly affected, and the addition of antibacterial agents such as hydroxyapatite can increase the osteogenic function of the material. Therefore, the alloy has good application prospects in the fields of dental implant, orthodontic treatment and oral and maxillofacial surgery. However, most of the current studies on antibacterial titanium alloys are in vitro experiments, and their long-term clinical effects and antibacterial mechanisms are still unclear and need further study.

Objective To evaluate the feasibility of transvenous embolization treatment for cerebral arteriovenous malformations(bAVM). Methods From November 2016 to April 2017, the information of 6 patients with brain arteriovenous malformation in our center accepting the intravenous radical embolization were collected, who were ruptured bAVM, bAVM with a single drainage vein, not suitable for surgery confirmed by neurosurgeon consultation or explicitly refused craniotomy. The modified Rankin Scale score of five patients were smaller than three before treatment.The location of draining vein flowing venous sinus was shown by rotational DSA and 3D reconstructed images.A liquid embolic agent was injected via Sonic catheter to completely embolism the brain arteriovenous malformation under controlling blood pressure and blocking the blood provisionally.The perioperative complications and modified Rankin Scale score were observed and recorded 30 days after treatment. Results The transvenous embolization treatment was successfully performed in six patients with 7 embolization procedures.There were no definite operation-related complications. the mRS of all cases were ≤1 within 30 days after operation. Conclusion The embolization technique via the internal jugular vein is feasible for bAVM patients with a single drainage vein,while the long-term outcome need more evaluations.

Objective To investigate the effect of moderate treadmill exercise together with modified hydroxyapatite chitosan composite hydrogel (CS/HA-g-CS) implantation on repair of full-thickness defects of articular cartilage in rats.Methods Full-thickness cartilage defects were drilled in the patellar groove of bilateral femoral condyles in a total of 24 male SD rats before they were randomly assigned into 4 groups.The control group (BC group) was subjected to no exercise or CS/HA-g-CS implantation;the chitosan group (CHI group) to CS/HA-g-CS implantation without exercise;the moderate treadmill exercise group (MIR group) to exercise 4 weeks after modeling without CS/HA-g-CS implantation;the CHI + MIR group to moderate treadmill exercise plus CS/HA-g-CS implantation 4 weeks after modeling.Half of the animals were sacrificed at week 8 and half at week 16 after operation.Femoral condyles were harvested for gross observation and histochemical measurement by O' Driscoll scoring system.mRNA expressions of glycosaminoglycan,collagen type Ⅱ and BMP-2 were detected by RT-PCR.Results Gross observation revealed:at 8 weeks after modeling,the CHI + MIR group was significantly better than the other 3 groups,with the BC group in the poorest (P ＜ 0.05);at 16 weeks after modeling,the BC group was significantly poorer than the other 3 groups (P ＜0.05) among which there were no significant differences (P ＞ 0.05).O 'Driscoll scoring revealed:at both 8 and 16 weeks after modeling,the CHI + MIR group was significantly better than the other 2 groups and the BC group significantly poorer than the other 3 groups (P ＜ 0.05) but there was no significant difference between the MIR and CHI + MIR groups(P ＞ 0.05).The expressions of collagen type Ⅱ,glycosaminoglycan and BMP-2 were significantly higher in the CHI + MIR group than in the other 3 groups (P ＜ 0.05) and significantly lower in the BC group than in the other 3 groups (P ＜ 0.05).Conclusions Moderate treadmill exercise together with CS/HA-g-CS implantation has significant positive effects on repair of full-thickness defects of articular cartilage in rats than merely moderate treadmill exercise or CS/HA-g-CS implantation alone.The defective cartilage repaired by moderate treadmill exercise together with CS/HA-g-CS implantation contains more collagen type Ⅱ and glycosaminoglycan and shows morphology of nearly normal cartilage.

Objective To apply iTRAQ technology to observe changes in protein expression group in the process of inducing C2C12 cells differentiation towards osteoblast by BMP-2.Methods The myoblast C2C12 cells were seeded in BMP-2 induced differentiation system for differentiation induction.In the 7th day,differentiation protein was extracted and labeled with iTRAQ reagent.Then,mass spectrometric detection,data analysis of differentially expressed proteins,and analysis of biological information were carried out.Results 23 significantly differentially expressed protein spots were screened by BMP-2-induced myoblast C2C12 differentiated cell protein expression profile analysis,where the protein was labeled with iTRAQ reagent.8 protein points were up-regulated,and 15 protein points were down-regulated.Trend classification found that the above differential protein had differential expression in each period of C2C12 cell osteogenic differentiation (1-7 days).Part of up-regulated protein in the early differentiation period showed high expression level;part of up-regulated protein in the late differentiation period showed high expression level;similarly,part of down-regulated protein in the early differentiation period presented low expression level;part of down-regulated protein in the late differentiation period showed low expression level.Preliminary identification showed SERCA3,Cytochrome bS,S100A4,ATPase inhibitor and ATPIF1 presented dynamic changes,which suggests that these proteins may be related to inducing osteogenic differentiation mechanism.Conclusion The results of differential protein expression trend show the necessity of full monitoring of C2C 12 cells osteogenic differentiation and indicate that iTRAQ technology is an effective method of studying protein changes of cellular molecule.Five proteins including SERCA3,Cytochrome b5,S100A4,ATPase inhibitor and ATPIF1 can be used as candidate targets for osteogenic differentiation mechanism research.

The mechanical properties of natural and synthetic extracellular matrices affect cellular processes and regulate tissue formation. In order to explore the optimal environment for chondrocytes growth in vitro, we investigated the relationship between the mechanical properties of the alginate beads and the ability of chondrocyte proliferation in this study. We measured the compressive properties of alginate with different concentrations by INSTRON 3365,and found that compressive moduli significantly increased with increasing alginate concentration. The rabbit chondrocytes were encapsulated in 1%, 2% and 3% (w/v) alginate beads at high (1 x 10(7)/ml) density. After 4 week's culturing, all the three groups resulted in the limited proliferation of the chondrocytes and the formation of cell clusters resembling cartilaginous tissues. Chondrocytes proliferation was more rapid on lower concentrate gels (1%, 2%) than on the higher concentrate gels (3%). These results suggested that the mechanical properties of scaffold architecture had certain effect on chondrocytes proliferation.
Alginates ; pharmacology ; Animals ; Cartilage, Articular ; cytology ; Cell Proliferation ; drug effects ; Cells, Cultured ; Chondrocytes ; cytology ; Compressive Strength ; drug effects ; Glucuronic Acid ; pharmacology ; Hexuronic Acids ; pharmacology ; Hydrogels ; pharmacology ; Rabbits

OBJECTIVETo study diagnosis and therapeutic efficacy of transient oeteoporods of the hip (TOH).

METHODSFrom January 2005 to February 2010, 5 patients with TOH were treated with traditional methods. All the patients were male, with an average age of 38.6 years (ranged, 27 to 46 years). The clinical manifestation, physical examination and imageology characteristic was investigated. The therapeutic efficacy was evaluated by Harris hip score.

RESULTSAll the patients were followed up, the duration ranged from 12 to 36 months (averaged, 24 months). The Harris hip score before treatment were 63.1, 86.0, 74.9, 63.6 and 64.8 respectively, while after 6 months treatment, the scores improved to 90.5, 94.5, 89.7, 93.9 and 87.8 respectively. Moreover, 6 months later, the abnormal signal disappeared in MR imaging and X-ray.

CONCLUSIONTransient osteoporosis of the hip is a self-resolving condition and a self-limited disease, the expectant treatment is useful for it.

Adult ; Female ; Hip Joint ; Humans ; Magnetic Resonance Imaging ; Male ; Middle Aged ; Osteoporosis ; diagnosis ; therapy ; Retrospective Studies

OBJECTIVETo evaluate the diagnostic value of serum angiopoietin-2 (Ang-2) level in pancreatic cancer patients.

METHODSSerum Ang-2 level was measured by enzyme-linked immunosorbent assays (ELISA) in samples from 116 patients with pancreatic cancer, 50 patients with chronic pancreatitis, and 50 normal control subjects.

RESULTSThe serum Ang-2 level in patients with pancreatic cancer [(1539.0 ± 449.3) ng/L] was significantly higher than those in patients with pancreatitis [(1044.6 ± 246.1) ng/L, P < 0.01] and normal control subjects [(1075.6 ± 228.2) ng/L, P < 0.01]. There was no significant difference of serum Ang-2 levels between patients with pancreatitis and normal controls. Pancreatic caner patients with lymph node metastasis had a significantly higher serum Ang-2 level [(1890.1 ± 354.9) ng/L] than those without metastasis [(1212.1 ± 224.2) ng/L, P < 0.01]. The area under ROC curve of serum Ang-2 level for diagnosis of pancreatic cancer was 0.819.

CONCLUSIONThe serum Ang-2 level can be a useful indicator for diagnosis of pancreatic cancer.

Adult ; Aged ; Angiopoietin-2 ; blood ; Enzyme-Linked Immunosorbent Assay ; Female ; Humans ; Lymphatic Metastasis ; Male ; Middle Aged ; Neoplasm Staging ; Pancreatic Neoplasms ; blood ; diagnosis ; pathology ; Pancreatitis ; blood ; ROC Curve ; Retrospective Studies

OBJECTIVETo investigate the clinicopathologic characteristics and prognosis of multiple primary synchronous colorectal carcinoma (synchronous CRC) and single colorectal carcinoma (single CRC).

METHODSClinicopathological data of 39 patients with synchronous CRC and 528 patients with single CRC from May 1996 to June 2001 were reviewed retrospectively.

RESULTSThe patients with synchronous CRC accounted for 6.9% of all the patients with colorectal carcinoma treated in our hospital during the same period. Compared with concurrent lesions, Dukes stage of the index lesions of synchronous CRC was more developed and the lymph node metastasis and vessel invasion occurred more frequently. In addition, it also had poorer differentiation. There were significant differences of Dukes stages and lymph node metastasis between the index lesions and single CRC. The incidence of adenomatous polyp in synchronous CRC was higher than that in single CRC(59.0% vs 25.0%,P<0.01). The sensitivity of preoperative colonoscopy examination was 76.9%, which was significantly higher than that of barium examination and exploration during operation. The total 5-year survival rate of synchronous CRC was significantly lower than that of single CRC (5.1% vs 28.2%,P=0.042), and no significant difference of total 5-year survival rate was found between single CRC patients and synchronous CRC patients undergone radical operation. Synchronous CRC patients undergone radical operation had longer survival as compared to those undergone palliative operation(P<0.01). Multivariate analysis indicated that Dukes stages, lymph node metastasis, vessel invasion and the type of operation were independent prognostic factors of synchronous CRC.

CONCLUSIONSSynchronous CRC and single CRC are not always similar in clinicopathologic characteristics and prognosis. Early finding, early diagnosis and radical operation are the keys to improve the survival rate of synchronous CRC.

Aged ; Colorectal Neoplasms ; pathology ; Female ; Humans ; Lymphatic Metastasis ; Male ; Middle Aged ; Neoplasm Staging ; Neoplasms, Multiple Primary ; pathology ; Prognosis ; Retrospective Studies ; Survival Rate