Advances in mechanisms of microglial function on demyelination and remyelination in EAE model / 中国免疫学杂志

Inflammatory cells infiltration and demyelination in the central nervous system (CNS) are the main pathological characteristics of multiple sclerosis(MS),an autoimmune disease in the CNS.Most of the related pathological studies are carried out in the animal model experimental autoimmune encephalomyelitis(EAE).Microglia(MG) are the primary immune effector cells of the CNS and their activation can play complex roles in demyelination and remyelination during EAE.In detail,M1 phenotype is an important cause of demyelination and detrimental to remyelination while M2 phenotype can promote remyelination and inhibit demyelination.In this review,we not only focus on advances in the direct mechanisms of microglial function on demyelination and remyelination in EAE model,also the indirect mechanisms by astrocytes.

Experimental study on effects of astragalus polysaccharide on treating EAE in mice and regulating activation of BV-2 microglial cell line / 中国免疫学杂志

Objective:To investigate the therapeutic effects of astragalus polysaccharide (APS) on experimental autoimmune encephalomyelitis(EAE) and to explore the regulating effects on microglia activation that is associated with the pathogenesis of EAE and its possible mechanisms.Methods:Animal experiments:EAE model was induced by MOG35-55in C57BL/6 mice.APS was given by gavage.EAE was scored according to a 0-5 scale to observe the therapeutic effects of APS.Cell experiments:The effects of lipopolysac-charide (LPS) on cell viability of BV-2 microglial cell line were investigated by MTT assay and then the appropriate concentration of LPS to activate the BV-2 microglial cell line was selected.The microglia activation model was established.The changes in BV-2 microglial cell line morphology were observed with an inverted microscope.The cytokines of TNF-α and IFN-γ in the cell culture supernatant of BV-2 microglial cell line were detected by ELISA.The activated BV-2 microglial cells were treated with APS in different concentrations.The regulatory roles of the APS on the BV-2 microglial cell activation were observed.Western blot and Real-time PCR method were used to measure the protein and mRNA level of the PD-L1 on the cell surface of BV-2 microglial cells treated with APS.Results:APS could effectively ameliorate the symptoms in EAE mice and could suppress neuroinflammation of EAE significantly.The microglia activation model in vitro induced by LPS was successful.APS in certain concentration could inhibit the activation of microglia,increase the viabilily of the active microglia.Meanwhile,it could downregulated the level of the cytokines including IFN-γ and TNF-α and upregulated the expression of protein and mRNA of PD-L1 on activated microglia.Conclusion:APS can effectively inhibit the autoimmune reaction of EAE and effectively suppress the microglia activation induced by LPS,reduce the pro-duction of IFN-γ and TNF-α.APS plays a crucial role in reducing the inflammation induced by microglia activation.The potential mech-anisms might be related to the upregualtion of the PD-1/PD-L1 pathway.

Biomechanical Comparison of Two Kinds of Internal Fixation in a Type C Zone II Pelvic Fracture Model / 中华医学杂志(英文版)

<p><b>BACKGROUND</b>Unstable pelvic fractures are complex and serious injuries. Selection of a fixation method for these fractures remains a challenging problem for orthopedic surgeons. This study aimed to compare the stability of Tile C pelvic fractures fixed with two iliosacral (IS) screws and minimally invasive adjustable plate (MIAP) combined with one IS screw.</p><p><b>METHODS</b>This study was a biomechanical experiment. Six embalmed specimens of the adult pelvis were used. The soft tissue was removed from the specimens, and the spines from the fourth lumbar vertebra to the proximal one-third of both femurs were retained. The pubic symphysis, bilateral sacroiliac joints and ligaments, bilateral hip joints, bilateral sacrotuberous ligaments, and bilateral sacrospinous ligaments were intact. Tile C pelvic fractures were made on the specimens. The symphysis pubis was fixed with a plate, and the fracture on the posterior pelvic ring was fixed with two kinds of internal fixation in turn. The specimens were placed in a biomechanical machine at a standing neutral posture. A cyclic vertical load of up to 500 N was applied, and displacement was recorded. Shifts in the fracture gap were measured by a grating displacement sensor.</p><p><b>STATISTICAL ANALYSIS USED</b>Paired-samples t-test.</p><p><b>RESULTS</b>Under the vertical load of 100, 200, 300, 400, and 500 N, the average displacement of the specimens fixed with MIAP combined with one IS screw was 0.46, 0.735, 1.377, 1.823, and 2.215 mm, respectively, which was significantly lower than that of specimens fixed with two IS screws under corresponding load (P < 0.05). Under the vertical load of 500 N, the shift in the fracture gap of specimens fixed with MIAP combined with one IS screw was 0.261 ± 0.095 mm, and that of specimens fixed with two IS screws was 0.809 ± 0.170 mm. The difference was significant (P < 0.05).</p><p><b>CONCLUSION</b>The stability of Tile C pelvic fractures fixed with MIAP combined with one IS screw was better than that fixed with two IS screws.</p>

The effects of Shadu Cao Mixture on immune functions of immunosuppression mice / 中国应用生理学杂志

<p><b>OBJECTIVE</b>To investigate the effects of Shadu Cao Mixture (SDCM, traditional Chinese medicine) on immune functions of immunosuppression mice.</p><p><b>METHODS</b>Fifty BALB/C mice were randomly divided into blank control group, model group, SDCM low-dose, middle-dose and high-dose group. Except the blank control group, other groups were intraperitoneal injected with cyclophosphamide (40 mg/kg) to establish immunosuppression mice model. The blank control group and model group received gavage administration with nonnal saline, while the other groups received gavage administration with different doses of SDCM (10, 20, 40 m/kg for 15 days) respectively. The number of leukocytes and serum levels of interleukin-2 (IL-2), tumor necrosis factor-α (TNF-α) and interferon-γ (IFN-γ) in peripheral blood, spleen index, and the function of NK cells were measured.</p><p><b>RESULTS</b>Compared with the model group , SDCM increased the number of leukocytes and serum concentrations of IL-2, TNF-α and IFN-γ in peripheral blood and improved the spleen index and the function of NK cells significantly (P < 0.05-0.01).</p><p><b>CONCLUSION</b>SDCM could remarkably enhance the immune functions of immunosuppression mice induced by cyclophosphamide.</p>

Value of P16 expression in the triage of liquid-based cervical cytology with atypical squamous cells of undetermined significance and low-grade squamous intraepithelial lesions / 中华医学杂志(英文版)

<p><b>BACKGROUND</b>The management of atypical squamous cells of undetermined significance/low-grade squamous intraepithelial lesions (ASCUS/LSIL) is still controversial and it is advisable to make a triage for these two cytological abnormalities. P16(INK4) (P16) has been shown to be a potential biomarker for predicting high-grade cervical intraepithelial neoplasia (CIN) and cervical cancer. The aim of the study was to determine the value of P16 expression by immunostaining method compared with high-risk human papillomavirus (HR-HPV) DNA test in the triage of ASCUS/LSIL women.</p><p><b>METHODS</b>Totally 86 eligible residual liquid-based cytological specimens with ASCUS and 45 with LSIL were obtained. All specimens were submitted to HR-HPV DNA test (HC2) and P16 immunocytochemical staining simultaneously. And all women underwent colposcopy and biopsy after cytology.</p><p><b>RESULTS</b>The positive rate of P16 staining was 32.6% in ASCUS and 42.2% in LSIL, which was significantly lower than that of HR-HPV test in both ASCUS (P < 0.05) and LSIL (P < 0.05). Moreover, the positive rate of P16 staining was 12.7% in normal histology, 61.5% in CIN 1, 87.0% in CIN 2-3, and 100.0% in cancer, in which P16 positive rate was significantly lower than HR-HPV positive rate in normal group. The sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV) and accuracy of P16 staining for predicting CIN 2 or more were 87.5%, 68.6%, 38.9%, 96.0%, and 72.1%, respectively in the ASCUS; while 90.0%, 71.4%, 47.4%, 96.2% and 54.7%, respectively in the LSIL, in which the specificity and accuracy of P16 staining were significantly higher than those of HR-HPV test in both ASCUS and LSIL (P < 0.05).</p><p><b>CONCLUSION</b>P16 immunostaining had significantly higher specificity and accuracy than HR-HPV DNA test for predicting for high-grade CIN and cervical cancer in ASCUS and LSIL and can be used for the triage of women with ASCUS/LSIL cytological abnormality.</p>

Sodium nitroprusside facilitates human sperm capacitation and acrosome reaction / 中华男科学杂志

<p><b>OBJECTIVE</b>To explore the effect of nitric oxide (NO) on human sperm capacitation and acrosome reaction (AR).</p><p><b>METHODS</b>Different concentrations of sodium nitroprusside (SNP) were added to the sperm suspension from 48 healthy fertile men, and the suspension was incubated in 1 x Earle at 37 degrees C for 1 hour. Progesterone was used to induce AR for 15, 30, 45 and 60 min, and then acid phosphatase (ACP) activity in the suspension before and after capacitation and at different time of AR was measured by p-nitrophenyl sodium phosphate assay. In the meantime, sperm motile parameters were assayed by CASA to observe sperm capacitation and AR.</p><p><b>RESULTS</b>ACP activity and sperm motile parameters increased in the 50 approximately 100 nmol/L NO concentration group, showed no significant variation in the 150 approximately 200 nmol/L group, and decreased in the 250 approximately 300 nmol/L group.</p><p><b>CONCLUSION</b>NO can facilitate sperm capacitation, AR and sperm motile parameters in low concentration and suppress them in high concentration. ACP activity assay of sperm is an objective and reliable method to evaluate sperm capacitation and AR in whole sperm population.</p>

Mismatch repair gene promoter methylation and expression in hydatidiform moles and the malignant transformation / 中国医学科学院学报

<p><b>OBJECTIVE</b>In this study, we assayed promoter hypermethylation and protein expression of the mismatch repair gene (MMR) hMLH1 and hMSH2 in gestational trophoblastic diseases to understand the significance of MMR promoter methylation and expression in the pathogenesis and malignant transformation of hydatidiform mole.</p><p><b>METHODS</b>DNA was extracted from chorion of early pregnancies, partial hydatidiform moles, complete hydatidiform moles, and invasive moles were over digested by methylation sensitive endonuclease Hpa II. Then the promoters were amplificated by polymerase chain reaction. The protein was detected by immunohistochemistry.</p><p><b>RESULTS</b>In the normal placenta, neither hMLH1 nor hMSH2 promoter methylation was detected. Expression of hMLH1 and hMSH2 in cytotrophoblasts was strongly positive, and that was negative or weakly positive in syncytiotrophobasts. In all normal chorion, expression of hMLH1 and hMSH2 in cytotrophoblasts was strongly positive. In partial hydatidiform mole and complete hydatidiform mole, the methylation of hMLH1 and hMSH2 promoters was significantly higher than that of early placenta (P < 0.05), and the protein expression in cytotrophoblasts was significantly lower (P < 0.05). In the invasive mole, hMLH1 and hMSH2 promoter methylation were not significantly different as compared with the partial hydatidiform mole and complete hydatidiform mole (P > 0.05). Expression of hMLH1 in the invasive mole (54.5%, 6/11) was not significantly different as compared with the partial hydatidiform mole and complete hydatidiform mole (P > 0.05). But expression of hMSH2 in the invasive mole (36.4%, 4/11) was weaker than that in complete hydatidiform mole (P = 0.044). Promoter methylation and less expression of hMSH2 had correlations in complete hydatidiform mole or invasive mole.</p><p><b>CONCLUSIONS</b>Strong expressions of hMLH1 and hMSH2 in the cytotrophoblasts of normal placenta may keep the genome stability. Promoter methylation and down-regulation of hMLH1 and hMSH2 are probably involved in the pathogenesis of hydatidiform mole.</p>