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An excessive immune response contributes to SARS-CoV, MERS-CoV and SARS-CoV-2 pathogenesis and lethality, but the mechanism remains unclear. In this study, the N proteins of SARS-CoV, MERS-CoV and SARS-CoV-2 were found to bind to MASP-2, the key serine protease in the lectin pathway of complement activation, resulting in aberrant complement activation and aggravated inflammatory lung injury. Either blocking the N protein:MASP-2 interaction or suppressing complement activation can significantly alleviate N protein-induced complement hyper-activation and lung injury in vitro and in vivo. Complement hyper-activation was also observed in COVID-19 patients, and a promising suppressive effect was observed when the deteriorating patients were treated with anti-C5a monoclonal antibody. Complement suppression may represent a common therapeutic approach for pneumonia induced by these highly pathogenic coronaviruses. One Sentence SummaryThe lectin pathway of complement activation is a promising target for the treatment of highly pathogenic coronavirus induced pneumonia.
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The main protease of coronaviruses and the 3C protease of enteroviruses share a similar active-site architecture and a unique requirement for glutamine in the P1 position of the substrate. Because of their unique specificity and essential role in viral polyprotein processing, these proteases are suitable targets for the development of antiviral drugs. In order to obtain near-equipotent, broad-spectrum antivirals against alphacoronaviruses, betacoronaviruses, and enteroviruses, we pursued structure-based design of peptidomimetic -ketoamides as inhibitors of main and 3C proteases. Six crystal structures of protease:inhibitor complexes were determined as part of this study. Compounds synthesized were tested against the recombinant proteases as well as in viral replicons and virus-infected cell cultures; most of them were not cell-toxic. Optimization of the P2 substituent of the -ketoamides proved crucial for achieving near-equipotency against the three virus genera. The best near-equipotent inhibitors, 11u (P2 = cyclopentylmethyl) and 11r (P2 = cyclohexylmethyl), display low-micromolar EC50 values against enteroviruses, alphacoronaviruses, and betacoronaviruses in cell cultures. In Huh7 cells, 11r exhibits three-digit picomolar activity against Middle East Respiratory Syndrome coronavirus.
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OBJECTIVE:To investigate the protective effects of insulin-glucose on myocardium in patients receiving cardiac valve replacement under cardiopulmonary bypass. METHODS:Totally 120 patients receiving combined cardiac valve replacement under cardiopulmonary bypass were divided into control group and observation group according to random number table,with 60 cases in each group. All patients were given routine operation. Control group was given Thomas cardioplegia and oxygenated blood with a ratio of 1:4(V:V)to protect myocardium at 4 ℃. Besides that,the observation group was additionally given Insulin injec-tion 10 IU/L and Glucose injection 10 g/L added into Thomas cardioplegia at 4 ℃ to protect myocardium. The levels of plasma brain natriuretic peptide(BNP)and cardiac troponinⅠ(cTnⅠ)before anesthesia induction(T0),at the end of cardiopulmonary by-pass(T1),12 h(T2),24 h(T3),48 h(T4),and 72 h(T5)after surgery,the rate of recovery of automatic heartbeat after opening aor-ta,the application of vasoactive agent(dopamine)at T1 and the occurrence of postoperative complications were observed and com-pared between 2 groups. RESULTS:At T0,there was no statistical significance in the levels of plasma BNP and cTnⅠ between 2 groups(P>0.05). The levels of plasma BNP and cTnⅠin 2 groups at T1-5 were significantly higher than T0,with statistical signifi-cance(P0.05). The dos-age of dopamine (at T1) and the incidence of complications in observation group were statistically lower than control group,with statistical significance(P<0.05). No severe ADR was found in 2 groups during or after surgery. CONCLUSIONS:Insulin-glucose can alleviate myocardial damage, reduce the dosage of vasoactive agent and the incidence of postoperative complications in pa-tients receiving combined cardiac valve replacement under cardiopulmonary bypass with significant protective effect on myocardium with good safety.
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Objective To sum up the clinical experience in diagnosis and treatment of spinal primitive neuroectodermal tumor (PNET). Methods Thirteen patients with spinal PNET were included in the study from 1999 to 2009. There were 8 males and 5 females with the mean age of 26.9 years. The lesions involved the cervical spine in 6 cases, the thoracic segment in 1 case, the lumbar segment in 5 cases and the sacrum in 1 case. The diagnosis of PNETs was made in nine patients by postoperative pathological examination. Among them, 6 patients received a preoperative CT-guided percutaneous biopsy. The other four patients were diagnosed only by CT-guided percutaneous biopsy. Osteolytic bony lesions and obvious neurological deficit were found in ten patients, while the other 3 had complained of local pain only. Nine patients had received operation followed by chemotherapy and radiotherapy. The other 4 underwent only chemotherapy and radiotherapy. The changes of symptoms and time of survival were recorded. Results Eleven patients were followed up with the mean of 21.8 months. The back pain in 7 patients who underwent operation relieved one month after the operation. The bladder and bowel function returned to normal condition after the operation. Among them, four patients died postoperatively. The mean survival time was 11.3 months. The otherthree patients survived with an average of 36 months. Three patients who had only received chemotherapy and radiotherapy died with an average of 7 months, while the other patient survived for 5 months. Conclusion The diagnoses of spine PNET mainly depend on pathological examination. Percutaneous CT-guided biopsy is a reliable method to confirm diagnose of tumor before surgery. The mortality rate of spinal PNET which is a highly malignant tumor is high. Operation can relieve clinical symptoms and improve patients' life quality, but not prolong the survive time.
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Epidermal growth factor receptor (EGFR) and its ligands (EGF and TGFalpha) are over-expressed in a variety of tumors. Immunization EGF-carrier protein inhibits tumor growth through abrogating binding of EGF to EGFR. Here, a chimeric protein of EGF and TGFalpha (E5T) was genetically fused to Staphylococcal enterotoxin A (SEA), a bacterial superantigenic protein which promotes humoral B cell response through enhancement of Ag-specific CD4 T cells activity. The resulted fusion proteins were expressed in Escherichia coli and purified though metal chelating affinity chromatography. Immunization of E5T-mSEA fusion protein in mice induced production of high titers antibodies, which recognize both EGF and TGFalpha. Anti- E5T-mSEA serum at dilution of 1:10 significantly inhibited growth of A431 cell lines but had little effect on 293T cell lines.
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Animals , Humans , Mice , Amino Acid Sequence , Cancer Vaccines , Allergy and Immunology , Cell Line, Tumor , Enterotoxins , Genetics , Epidermal Growth Factor , Genetics , Escherichia coli , Genetics , Metabolism , Immunization , Mice, Inbred C57BL , Molecular Sequence Data , Random Allocation , ErbB Receptors , Allergy and Immunology , Recombinant Fusion Proteins , Genetics , Allergy and Immunology , Transforming Growth Factor alpha , GeneticsABSTRACT
This study sought to detect the pathological changes of anterior cruciate ligament (ACL) and medial collateral ligament (MCL) under injury stretch. Bone-ACL-Bone (B-ACL-B) and B-MCL-B complexes were isolated from 20 male Wister rats, and were immersed in phosphate buffered saline. The complexes were stretched with 10% or 20% strain for 10 min or 30 min. After being stretched, the specimens were fixed in 10% buffered formalin, then mounted in paraffin. Sections were stained with Alcian blue-PAS and HE. The following results were found: In the control group, the matrix in ACL contained much more GAGs, as compared with that in MCL. When stretched with 10%, most of the fibroblasts in ACL were elongated like spindles in shape, and some pyknotic nuclei were found increased with stretching time. With 20% strain, ACL showed disruption in parts of collagen fibrils and lysis. But MCL was often torn at its tibia end. The injury can be detected in pathological slices under microscope, even this injury can not be found with naked eye. This injury first starts with the disturbance of the nucleus in the ligament, but following further stretching, it will extend to the rupture of collagen fibrils, and the serious injury of the fibroblasts is especially bad to the repair of the ligament.
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Animals , Male , Rats , Anterior Cruciate Ligament , Pathology , Anterior Cruciate Ligament Injuries , Medial Collateral Ligament, Knee , Wounds and Injuries , Pathology , Rats, Wistar , Stress, MechanicalABSTRACT
BACKGROUND: The changes in trabecular bone microarchitecture in osteoporosis have aroused much attention. The decrease in the number of trabecular nodes and increase in the number of free ends are found in osteoporosis, but the mechanism is still unclear.OBJECTIVE: To observe the trabecular remodeling process in ovariectomized rats as the osteoporosis models electron microscopically, and to explore the reasons for the decrease in the number of trabecular nodes and increase in the number of free ends.DESIGN: Randomized and controlled animal trial.SETTING: Department of Orthopedics, Third Hospital of Peking University.MATERIALS: The experiment was conducted in the Animal Laboratory, Third Hospital of Peking University from September 1999 to February 2000. Thirty-six female Wistar rats of 3 months old and 240-280 g were selected and randomly divided into ovariectomized group and control group with 18 rats in each group. The rats were observed at 4,8, and 12 weeks postoperatively with 6 rats at each time point.METHODS: The rats of ovariectomized group were subjected to ovariectomy 1 week after feeding, but the control group was not. The changes of proximal tibia trabecular microarchitecture was observed under scanning electron microscope at 4, 8 and 12 weeks, respectively, and the osteoclast, osteoblast, and structure of cell organs were observed under transmission electron microscope.MAIN OUTCOME MEASURES: [1]The re modeling process after ovariectomy by electron microscope; ②morphological changes of trabecular bone.RESULTS: [1]Scanning electron microscope observation showed that trabecular bone remodeling was distributed in every region of trabecular microarchitecture, especially St and Nd-St region. After ovariectomy, the transverse trabecular was easier to be perforated and broken; the trabecular network was almost intact at 4 weeks, but gradually damaged at weeks 8 and 12; moreover, the collagen fibers on the surface of trabecular bone were scrappy, disorder and thinner. ②By the transmission electron microscopic study, the tibial osteoclast were found active at 12 weeks. When absorbing cancellous bone, osteoclast closely adhered to its surface, and digitations stretched into the cancellous bone. The shape and size of digitations were significantly different, and around them, lucent area was observed. Osteoclast was polynucleation with abundant kytoplasm, and there were plenty of Golgi complex, smooth endoplasmic reticulum and mitochondrium. Lysosome inclusion compounds with different sizes and electron density were found in cells. Osteoblast was rarely found, and cell edge was rough, with bone lacuna.CONCLUSION: Bone remodeling is significantly active in St and Nd-St region of trabecular bone in ovariectomized rats.This may be the reason for the decrease in the number of trabecular nodes and increase in the number of free ends.
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[Objective]Giant cell tumor of bone is notorious for its local aggressive behavior and its tendency to recur after operative treatment.Bisphosphonates is the drug of anti-osteoporosis.It is found also have anti-cancer effect recently.We conducted experiment examing the effect of bisphosphonates alendronate on the growth and survival of the cells.To study if bisphosphonates are capable of inducing cells death and significantly inhibiting their growth in vitro.[Method]Cells viability was detected by MTT Assay after the tumor cells were cured with different concentration and different time.Tumor cells apoptosis with in situ TUNEL assay and flow cytometry was detected.The active Caspase-3 was also detected.[Result]After exposure to alendronate,the cells exhibited the characteristic features of cell shrinkage,rounding and partial detachment,and demonstrated the lobulated appearance of apoptotic cells.It was much more prominent while the treating time prolonged or the concentration increased.Alendronate((5 200) M) treatment for 24 h,resulted in 2.79%~31.17% decrease in cell viability,and 11.13%~49.94% for 72 h,respectively.A significant dose-dependent and time-dependent decrease in the number of viable cells was observed in the GCT cells.After Alendronate treat for 24 h,the mean cell population in apoptosis was 14.32% at concentration 5 mmol/l,and 40.24% at 200 mmol/l.It was up to 18.41% and 42.22% respectively after 48 h.In Alendronate-treated GCT cells,Caspase-3 activation was observed.The cell response varied with doses of Alendronate showing the levels of Caspase-3 expression with a dose dependent response.[Conclusion]In conclusion,we demonstrated that bisphosphonate alendronate could inhibit GCT cells in the present study.This response was time-dependent and dose-dependent.Alendronate inducing apoptosis in GCT cells is mediated by the activation of Caspase-3.
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<p><b>OBJECTIVE</b>To construct the adenoviral vector bringing hVEGF(121) cDNA for evaluation of the possibility of VEGF gene therapy in ischemic bone disease.</p><p><b>METHODS</b>Human vascular endothelial growth factor (hVEGF(121)) cDNA obtained from the plasmid pCDI/VEGF(121) was cloned into plasmid pshuttle and further cloned to Adeno-X Viral DNA. The recombinant adenoviral plasmid was identified and then transferred to the adenoviral packaging cell HEK293 by lipofectamine mediated gene transfer method to pack the virus. After titilating the virus, the mouse bone marrow stromal cells (MSC) were transfected by the adenovirus and the expression of VEGF gene was detected.</p><p><b>RESULTS</b>The recombinant Adeno-VEGF(121) was correctly constructed and confirmed by restriction endonuclease analysis and DNA sequencing analysis. After MSCs were tranfected by the virus, RT-PCR showed that hVEGF(121) mRNA was transcripted from the hVEGF(121) gene. Western blot and immune histochemistry showed VEGF(121) protein was expressed in transgene MSCs.</p><p><b>CONCLUSION</b>The recombinant adenoviral vector bringing hVEGF(121) cDNA was successfully constructed and the transgene MSC expressed hVEGF gene in vitro, it provided the further foundation of VEGF gene therapy for bone ischemic diseases.</p>
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Humans , Adenoviridae , Genetics , Blotting, Western , Cells, Cultured , DNA, Complementary , Genetics , Endothelial Growth Factors , Genetics , Metabolism , Gene Expression , Gene Transfer Techniques , Genetic Vectors , Genetics , Immunohistochemistry , Lymphokines , Genetics , Metabolism , Vascular Endothelial Growth Factor A , Vascular Endothelial Growth FactorsABSTRACT
<p><b>OBJECTIVE</b>To construct a retroviral vector carrying human vascular endothelial growth factor (hVEGF (121)) cDNA for evaluation of the possibility of VEGF gene therapy in ischemic bone disease.</p><p><b>METHODS</b>hVEGF(121) cDNA was obtained from the plasmid pCDI/VEGF(121) and cloned into retroviral plasmid pLXSN. Recombinant plasmid was transferred to the retro virus packaging cell, PT-67, by lipofectamine mediated gene transfer. Mouse bone marrow stromal cells (MSCs) were transfected by the retrovirus. The integration of the hVEGF(121) cDNA into MSC genomic DNA and expression of the VEGF gene was detected. Proliferation assays of human umbilical vein endothelial cells (HUVECs) by VEGF(121) in culture medium were performed.</p><p><b>RESULTS</b>Recombinant pLXSN/VEGF(121) was correctly constructed and confirmed by restriction endonuclease analysis and DNA sequencing analysis. hVEGF(121) gene was integrated into MSC genomic DNA after transfection, and the VEGF(121) protein was expressed. Proliferation assays showed VEGF(121) in culture medium was a biologically active protein and had a mitogenic effect on HUVEC.</p><p><b>CONCLUSIONS</b>Recombinant retroviral vector carrying hVEGF(121) cDNA was successfully constructed. VEGF (121) protein expressed by MSCs had mitogenic effect biologically. This provides a further foundation for VEGF gene therapy for bone ischemic disease and bone tissue engineering.</p>
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Animals , Humans , Mice , Bone Marrow Cells , Metabolism , Cell Division , DNA, Complementary , Genetics , Endothelial Growth Factors , Genetics , Endothelium, Vascular , Cell Biology , Genetic Therapy , Lymphokines , Genetics , Plasmids , Retroviridae , Genetics , Stromal Cells , Metabolism , Transgenes , Vascular Endothelial Growth Factor A , Vascular Endothelial Growth Factors , Virus AssemblyABSTRACT
Objective To evaluate the possibility and clinical value of total spondylectomy for the treatment of spinal tumors and to investigate a reliable method of spinal reconstruction after total spondylectomy. Methods Twenty seven cases of spinal tumors which eroded both vertebral body and its attachments were treated with total spondylectomy and internal fixation as reconstruction techniques. There were benign, malignant and metastatic tumors, which involved different levels from upper cervical to lower lumbar spines. One to 3 spinal vertebrae were removed. Results Twenty three cases were followed up for 7 to 96 months (with an average of 25 months). Among them, 1 case of L 5 malignant neurofibroma and 1 case of C6,7 giant cells tumor recurred in 10 and 12 months after operation, but the patients refused further treatment. One case of C2-4 chordoma recurred 1 year after operation, after second surgery, the result was satisfactory. No recurrent signs were found in the rest of 20 cases. Among 25 cases with neurological lesions, obvious improvement were obtained in 23 after operation. Conclusion For patients with involvement of spinal vertebra eroded by tumors, total spondylectomy is an effective procedure. After total spondylectomy, spinal stability can be reconstructed by stable internal fixation system.
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Objective To observe the adipocytic differentiation potential of bone marrow stromal cells (BMS), and the effect of simvastatin on adipocytic differentiation of bone marrow stromal cells in vitro, and to elucidate the mechanisms of anabolic effect of simvastatin on bone formation. Methods BMS from femur and tibia of adult female BALB C mice were cultured in vitro. Changes of alkaline phosphatase (ALP) activity were determined after treatment with adipogenetic agonist (hydrocortisone 0 5 ?mol/L and indomethacin 60 ?mol/L, HI) for 6 days. Thenexpression of lipoprotein lipase (LPL) mRNA was detected by RT PCR after treatment with HI and different concentration of simvastatin for 72 h. Adipogenetic differentiation were also observed with Oil Red O staining and fluorescence activated cell sorting (FACS) after treatment with HI and different concentration of simvastatin or 100 ?g/L rhBMP 2 for 12 days. Results After BMS were treated with HI for 6 days, ALP activity was significantly decreased ( P
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Objective To study the clinical features, laboratory index and therapy of hypoplastic myelodysplastic syndrome. Methods 8 patients with hypoplastic MDS by using the method of bone marrow smear and bone marrow biopsy were studied. T lymphocyte subsets were analyzed by flow cytometry. 8 patients were treated with personalized therapy. Results All the patients of this group had hypoplastic bone marrow with more than two parts, bone marrow hypocellularity and characteristics of ineffective hematopoiesis. The analysis of T lymphocyte subsets showed that 5 of 8 patients had abnormal CD+4/CD+8 ratios. After personalized treatment, there were 2 obvious remission cases, 3 partial remission cases, 2 progression cases and 1 inefficacy case. Conclusion Hypoplastic MDS is characterized by bone marrow hypocellularity and ineffective hematopoiesis, which showed immunological abnormalities. Personalized therapeutic strategy may prolong survival in patients with hypoplastic MDS.
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Objective:To evaluate the antitumor activity of recombinant SEA for therapy of B16 melanoma established in C57BL/6 mice. Methods:C57BL/6 mice with melanoma were treated with the purified rSEA. The tumors were isolated and weighted. Results:Tumor growth was apparently inhibited by rSEA at high, middle, and low doses intraperitone-ally, whose inhibition ratio were 79.3% , 75.6 % and 73. 8% respectively. rSEA treatment in situ could inhibit tumor growth more effectively(90.6% ). Further study showed that numerous CD8+ and CD4+ T cell were infiltrated in tumor tissues, which were consistent with tumor growth inhibition induced by rSEA. Conclusions: rSEA could inhibit tumor growth effectively, especially the treatment in situ. This study paves the way for tumor immunotherapy with targeted SEA.