Salmonella-mediated blood‒brain barrier penetration, tumor homing and tumor microenvironment regulation for enhanced chemo/bacterial glioma therapy

Chemotherapy is an important adjuvant treatment of glioma, while the efficacy is far from satisfactory, due not only to the biological barriers of blood‒brain barrier (BBB) and blood‒tumor barrier (BTB) but also to the intrinsic resistance of glioma cells via multiple survival mechanisms such as up-regulation of P-glycoprotein (P-gp). To address these limitations, we report a bacteria-based drug delivery strategy for BBB/BTB transportation, glioma targeting, and chemo-sensitization. Bacteria selectively colonized into hypoxic tumor region and modulated tumor microenvironment, including macrophages repolarization and neutrophils infiltration. Specifically, tumor migration of neutrophils was employed as hitchhiking delivery of doxorubicin (DOX)-loaded bacterial outer membrane vesicles (OMVs/DOX). By virtue of the surface pathogen-associated molecular patterns derived from native bacteria, OMVs/DOX could be selectively recognized by neutrophils, thus facilitating glioma targeted delivery of drug with significantly enhanced tumor accumulation by 18-fold as compared to the classical passive targeting effect. Moreover, the P-gp expression on tumor cells was silenced by bacteria type III secretion effector to sensitize the efficacy of DOX, resulting in complete tumor eradication with 100% survival of all treated mice. In addition, the colonized bacteria were finally cleared by anti-bacterial activity of DOX to minimize the potential infection risk, and cardiotoxicity of DOX was also avoided, achieving excellent compatibility. This work provides an efficient trans-BBB/BTB drug delivery strategy via cell hitchhiking for enhanced glioma therapy.

Effects of different routes of heparin on instant blood-mediated inflammatory reaction after portal vein islet transplantation / 中南大学学报(医学版)

OBJECTIVES@#Heparin is mainly used as an anticoagulant in clinic, and it also has a certain anti-inflammatory effect. At present, after portal vein islet transplantation in diabetic patients, heparin is mainly infused through the peripheral veins of the limbs to achieve the purpose of anticoagulation and protection of the graft, rather than through the portal vein. In this study, animal experiments were conducted to investigate the effect of heparin infusion via the portal vein and marginal ear vein on the instant blood-mediated inflammatory reaction (IBMIR) after portal vein islet transplantation, which is the choice of anticoagulation methods for clinical islet transplantation to provide a basis for decision-making.@*METHODS@#A total of 50 neonatal pigs (Xeno-1 type, 3-5 days) were selected. Islets were isolated and purified from the pancreas of neonatal pigs. Ten non-diabetic Landrace pigs (1.5-2.0 months) served as recipients, and 12 000 IEQ/kg neonatal porcine islets were transplanted into the liver through the portal vein. All recipients received bolus injection of 50 U/kg of heparin 10 minutes before transplantation. After the bolus injection of heparin, the experimental group received heparin via the portal vein [10 U/(kg·h), 5 recipients], and the control group received heparin via the marginal ear vein [10 U/(kg·h), 5 recipients]. The superior vena cava blood was collected from the 2 groups pre-operation at 1, 3, 24 h post-operation of the transplantation. The portal vein blood was collected from the experimental group at 1 and 3 h after the transplantation as well. The levels of complement C3a, C5a, thrombin-antithrombin complex (TAT), β-thromboglobulin (β-TG), and D-dimer as well as activated partial thromboplastin time (APTT) in superior vena cava blood from 1 and 3 h post-transplantation were detected in the 2 groups, and the levels of anti-Xa and anti-IIa in the portal vein and superior vena cava blood from 1 and 3 h post-transplantation in the experimental group were detected. Twenty four hours after the transplantation, the liver tissues in the 2 groups were collected for pathological examination to observe the inflammatory cell infiltration and peripheral thrombosis around the islets graft in liver.@*RESULTS@#Before transplantation, there was no statistically significant difference in C3a, C5a, TAT, β-TG, D-dimer levels and APTT between the 2 groups (all P>0.05). At 1 and 3 h after transplantation, the C3a, TAT, and D-dimer levels in the experimental group were significant decreased than those in the control groups (all P<0.05), and at 3 h after transplantation the C5a was significant decreased than that in the control group (P<0.05). At 1 and 3 h after transplantation, the anti-Xa and anti-IIa levels in the portal vein blood were significantly increased than those in the superior vena cava blood in the experimental group (all P<0.05). Pathological results showed the presence of islet cell clusters in the liver blood vessels. The thrombus formation and neutrophil infiltration around islet graft was not obvious in the experimental group, while massive thrombus formation and neutrophil infiltration in the control group.@*CONCLUSIONS@#Compared with marginal ear vein infusion of heparin, the direct infusion of heparin in the portal vein has a certain inhibitory effect on complement system, coagulation system activation and inflammatory cell infiltration in portal vein islet transplantation, which may attenuate the occurrence of IBMIR.

Comparison of Autogenous Tooth Materials and Other Bone Grafts

Autogenous odontogenic materials are a new, highly biocompatible option for jaw restoration. The inorganic component of autogenous teeth acts as a scaffold to maintain the volume and enable donor cell attachment and proliferation; the organic component contains various growth factors that promote bone reconstruction and repair. The composition of dentin is similar to that of bone, which can be a rationale for promoting bone reconstruction. Recent advances have been made in the field of autogenous odontogenic materials, and studies have confirmed their safety and feasibility after successful clinical application. Autogenous odontogenic materials have unique characteristics compared with other bone-repair materials, such as the conventional autogenous, allogeneic, xenogeneic, and alloplastic bone substitutes. To encourage further research into odontogenic bone grafts, we compared the composition, osteogenesis, and development of autogenous odontogenic materials with those of other bone grafts. In conclusion, odontogenic bone grafts should be classified as a novel bone substitute.

Comparison of Autogenous Tooth Materials and Other Bone Grafts

Autogenous odontogenic materials are a new, highly biocompatible option for jaw restoration. The inorganic component of autogenous teeth acts as a scaffold to maintain the volume and enable donor cell attachment and proliferation; the organic component contains various growth factors that promote bone reconstruction and repair. The composition of dentin is similar to that of bone, which can be a rationale for promoting bone reconstruction. Recent advances have been made in the field of autogenous odontogenic materials, and studies have confirmed their safety and feasibility after successful clinical application. Autogenous odontogenic materials have unique characteristics compared with other bone-repair materials, such as the conventional autogenous, allogeneic, xenogeneic, and alloplastic bone substitutes. To encourage further research into odontogenic bone grafts, we compared the composition, osteogenesis, and development of autogenous odontogenic materials with those of other bone grafts. In conclusion, odontogenic bone grafts should be classified as a novel bone substitute.

Abnormal neurobiochemical metabolites in the first / 中南大学学报(医学版)

OBJECTIVES@#To explore the metabolite characteristics in medial prefrontal cortex (mPFC) by @*METHODS@#A total of 46 patients with the first-episode schizophrenia (FES), 49 people with clinical high risk (CHR), 61 people with genetic high risk (GHR), and 58 healthy controls (HC) were enrolled. The levels of N-acetylaspartylglutamate+N-acetylaspartate (tNAA), choline-containing compounds (Cho) and myo-inositol (MI), glutamate+glutamine (Glx) in medial prefrontal cortex were measured by single-voxel @*RESULTS@#There were significant differences in Glx, tNAA, and MI concentrations among 4 groups (all @*CONCLUSIONS@#The decreased levels of MI and Glx in the FES patients suggest that there may be glial functional damage and glutamatergic transmitter dysfunction in the early stage of the disease. The compensatory increase of metabolites may be a protective factor for schizophrenia in the genetic individuals.

Imaging study on the homing of regulatory T cells in humanized heterologous liver tissue transplan-tation mouse model / 中华核医学与分子影像杂志

Objective To explore the homing of DiR labeled regulatory T cells ( Tregs) in human-ized heterologous liver tissue transplantation mouse model. Methods The fluorescence intensities of Tregs labeled with different concentrations of DiR dye and different incubation times were measured, and the cell viability was measured by 3-( 4, 5-dimethylthiazol-2-yl )-5-( 3-carboxymethoxyphenyl )-2-( 4-sulfophenyl )-2H-tetrazolium ( MTS) assay to determine the optimal incubation time and dye concentration. The effect of DiR dye on the function and phenotype of Tregs was verified by flow cytometry. The xenogeneic liver tissue transplantation mouse model was constructed and the immune system was reconstituted. Small animal fluores-cence imaging was performed at different time points after infusion of Tregs. Immunohistochemistry analysis was used to analyze immune reconstitution and lymphocyte distribution in vivo. One-way analysis of variance and Dunnett-t test were used to analyze the data. Results With the increase of DiR concentration and incu-bation time, the fluorescence intensity of Tregs increased and gradually weakened after reaching the peak at 3 d. The cell viability of the 5. 00 μg/ml and 20. 00 μg/ml groups was significantly lower than that of the control group (culture medium) at various time points (F=120.142-182.025, t=9.969-19.329, all P<0. 05) . After incubation for 30 min and 60 min, the activity of Tregs was also significantly lower than that of the control group (F=21.826-301.968, t=6.897-40.016, all P<0.05). Tregs were finally co-incubated with DiR dye at a concentration of 2.50 μg/ml for 5 min, which was used further in vivo experiments. The flow cytometry showed that DiR dye did not affect the phenotype or the function of Tregs. The small animal fluorescence imaging showed that Tregs could locate in the graft area of mouse model. Immunohistochemical analysis showed that Tregs could improve lymphocyte infiltration induced by immune reconstitution. Conclu-sion After labeling Tregs with DiR dye, the distribution of Tregs can be directly observed by fluorescence imaging, which is a promising imaging method for Tregs tracer.

Chemical Constituents in Atrichum Undulatum var. Gacelisetum / 中国药师

Objective:To find out the chemical constituents in Atrichum undulatum var. gacelisetum.Methods:The compounds were isolated by silica gel and TLC, and purified by recrystallization from the ethanol extract. The structures of the compounds were elucidated by spectral analysis and physicochemical properties. Results:Six compounds were obtained and the structures were identified as dotriacontane ( 1 ), montanic acid ( 2 ), β-sitosterol ( 3 ), daucosterol ( 4 ), luteolin 7-O-D-glucoside ( 5 ) and luteolin ( 6 ). Conclusion:Compounds 1-6 are isolated from the species for the first time.

Ultrasound molecular detection of immediately blood-mediated inflammatory reaction induced by islets transplantation in vitro / 中南大学学报(医学版)

OBJECTIVE@#To study the feasibility of ultrasonic molecular imaging of immediately blood-mediated inflammatory reaction (IBMIR) in vitro.
@*METHODS@#IBMIR models in vitro were divided into 3 groups: Group A, no microbubbles were added; Group B, non-targeted micro-bubbles were added; Group C, Lys-Gly-Asp-Ser (KGDS)-targeted microbubbles (MBK) were added. The ultrasonic enhancement of IBMIR in loops by ultrasonic contrast imaging was evaluated.
@*RESULTS@#The contrast-enhanced US imaging did not show thrombus formation in the group A, whereas the thrombus was found in the Group B and C with a change in filling defects or ring enhancement, respectively. The time for detecting thrombosis was (7.3 ± 0.5) min and (13.2 ± 0.6) min in Group B and Group C, respectively (P<0.05). The average-gray scales of thrombus in Group B and Group C were 31.22 ± 3.56 and 75.85 ± 5.21, respectively (P<0.05). The fluorescence microscope also showed that MBK was attached to thrombus surrounding islets.
@*CONCLUSION@#IBMIR model in vitro showed that KGDS-targeted ultrasound contrast agent could adhere to thrombus shell surrounding islets and molecular target ultrasonography could image these thrombi noninvasively and effectively.

Effects of self-differentiation, social support and social adaption on suicidal ideation in college students / 中华行为医学与脑科学杂志

Objective To explore the effects of self-differentiation,social support,social adaptation on suicidal ideation.Methods A simplified cluster sampling method,involving the random selection of 3097 college students in 23 departments,was used to estimate the scores of Chinese version of Self Differentiation Inventory for university student(SDI),Social Support Rating Scale(SSRC),College Student Adaptability Scale (CSAS) and Adult Suicidal Ideation Questionnaire(ASIQ).The independent-samples t-test,Pearson correlation coefficients and stepwise regression analyses were used as statistical analysis techniques.Results The correlation coefficients were negatively significant between suicidal ideation and self-differentiation,social support and social adaptation (r=-0.24,-0.17,-0.29,P＜0.001).Social adaptation showed the strongest predictability for suicidal ideation (β=-0.19,P＜0.001),followed by self-differentiation (β3=-0.13,P＜0.001),social support (β3=-0.08,P＜0.001).Independent samples t-test showed that college students with suicidal ideation showed a significant reduction in interpersonal adaptation,social support,self-differentiation compared to those without suicidal ideation.Conclusion Self-differentiation level,social support and social adaptability may be effective predictors for suicidal ideation among college students.Future intervention programs may focus on enhancing the interpersonal skills of college students to reduce prevalence of suicidal behavior.

THE HISTOLOGICAL AND IMMUNOCYTOCHEMICAL OBSERVATION OF THE INTERMEDIATE TROPHOBLAST OF THE HUMAN DECIDUA AT THE IMPLANTATION SITE / 解剖学报

This report presents microscopic observation on morphological and immuno- cytochemical characteristics of the trophoblast cells of the human decidua at the implantation site in the first trimester pregnancy .The infiltration of a unique type of large cells different from cytotrophoblast (CT) and syncytotrophoblast (ST) was found in the decidua at the implantation site. These unique cells are termed inter- mediate trophoblast (IT). They are typically mononucleate, but may be binucleate or multinucleate. The mononucleate cells vary in shape from round, polyhedral spindle shaped. Their cytoplasm is typically abundant and eosinophilic or amphophilic. The nuclei may vary in size and shape. These cells usually distribute around the spiral arterioles, differse blood vessel wall, penetrate into the lumen, and even replace the blood vessel wall totally. Immunocytochemically, both these cells and ST are stained positive for HCG and HPL. However, the HCG-stained Cell population of IT.is much lower than that of ST,while the of HPL stained cell population of IT is significantly higher than that of ST.On the other hand,neither HCG nor HPL are positive in CT. The results of SP-1 ?-HCG usually go with those of HCG.in CT, ST and IT.The PAPP-A gives non specific staining result. It is believed that IT,with its distinct morphological and immunocytochemical feats,is regarded as a transitional form in the shift from CT to ST.

THE IMMUNOCYTOCHEMICAL OBSERVATION OF NEUROENDOCRINE CHARACTERISTIC IN MICE THYMIC NURSE CELLS / 解剖学报

The arginine vasopressin (AVP) and oxytocin (OT) in thymic nurse cells (TNCs) of mice were stained by the method of immunogold and indfrect immunofluorescence, PAP immunocytochemical technique. TNCs of mice were shown immunocytochemical reactivity with antfserum of AVP and OT. The posttive areas were much denser near the cells membrane and around TNC-lymphocytes (TNC-Ls). It was implicated that TNCs might serve as neuroendocrine cells and might play a role in TNC-Ls differentiation via secreting AVP and OT.