Objective: To research the activity of antibacterial proteins isolated from Musca domestica during larvae-pupae metamorphosis. Methods: The 5-day-old larvae of Musca domestica were injured with a needle. 24h later, the larvae which had changed into pupae were selected. The antibacterial protein was isolated by a four-step protocol including grinding, heating, CM-sepharose F. F. cationexchange chromatography and another CM-sepharose F. F. chromatography. Antibacterial activities of samples were tested by an ultrasensitive radial diffusion assay using Staphylococcus aureus as the indicator organism. The molecular weight of the isolated protein was determined by SDS-PAGE.Results: The molecular weight of this isolated protein was 43kDa, and its antibacterial activity was strong. Conclusions: A kind of protein with strong antibacterial activity can be produced in the Musca domestica during larvae-pupae metamorphosis.

Staphylococcus aureus is a major cause of hospital-acquired infection. Because the bacteria are very easy to become resistant to antibiotics, vaccination is a main method against S. aureus infection. Clumping factor B (ClfB) is an adhesion molecule essential for S. aureus to colonize in the host mucosa and is regarded as an important target antigen. In this study, we successfully used Escherichia coli to express a segment encoding the N1-N3 regions of ClfB protein (Truncated-ClfB) cloned from S. aureus. The protein was purified by affinity and ion exchange chromatographies and gel filtration. Rabbits were immunized three times with purified Truncated-ClfB. After that, blood was collected to prepare serum which were then used for measurement of antibody level. Phagocytosis of S. aureus opsonized by the serum was determined by a flow cytometry. Results show that the serum IgG titer reached 1:640 000. Phagocytosed S. aureus by polymorphonuclear leukocytes were significantly more when the bacteria were opsonized by the serum from Truncated-ClfB immunized rabbits than those from no immunized group (P < 0.01). Therefore, the results indicated that Truncated-ClfB could be a promising vaccine candidate against S. aureus infection.
Adhesins, Bacterial ; immunology ; Animals ; Antibodies, Bacterial ; blood ; Escherichia coli ; Flow Cytometry ; Immune Sera ; Immunoglobulin G ; blood ; Opsonin Proteins ; immunology ; Phagocytosis ; Rabbits ; Staphylococcal Infections ; immunology ; Staphylococcus aureus

Objective To investigate the role of serum specific IgE(sIgE)antibodies,autoantibody and contact allergens in the pathogenesis of urticaria and the possible correlation among them.Methods The serum sIgE antibodies,autoantibody and contact allergens were tested by IVT kit,autologous serum test-ing and patch testing in145cases of urticaria.Results72.4%(84/116)of patients were positive with spe-cific IgE antibodies,among them13.8%(16/116)were strongly positive.37.7%(20/53)patients were pos-itive with autologous serum testing.In twenty-six patients the above two antibodies were tested.Specific IgE antibodies were found to be strongly positive in4(33.3%)of12patients with negative autologous testing,while in none of14patients with positive autologous testing.Patch testing was performed in21patients with chronic urticaria,90.5%(19/21)patients were positive to15of20allergens tested.Conclusion The pathogenesis of urticaria is complicated,which may include allergy to food,aeroallergens,contact allergens,as well as autoimmunity.Different allergic reactions may be present in the same individual.Contact allergens may be the factor responsible for contact urticaria.

We studied the effect of surfactin on cell proliferation, apoptosis and the cytoskeleton in human breast cancer cell line MCF-7 in vitro. The result of 3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) showed that the surfactin inhibited proliferation of MCF-7 cells in a dose- and time-dependent manner, with IC50 at 48 h of 27.3 micromol/L. Surfactin-induced cell death was considered to be apoptotic by observing the typical apoptotic morphological changes by AO/EB staining. Flow cytometric analysis also demonstrated that surfactin caused time-dependent apoptosis of MCF-7 cells through cell arrest at G2/M phase. Immunofluorescence and Western blotting showed that surfactin significantly suppressed the expression of vimentin, induced the alpha-tubulin depolymerization and rearrangement and then the skeleton system of the cells changed dramatically. Based on our findings, surfactin can significantly inhibit the growth of MCF-7 cells and induce apoptosis.
Antineoplastic Agents ; pharmacology ; Apoptosis ; drug effects ; Breast Neoplasms ; pathology ; Cell Line, Tumor ; Cell Proliferation ; drug effects ; Cytoskeleton ; drug effects ; Female ; Humans ; Lipopeptides ; pharmacology ; Peptides, Cyclic ; pharmacology

We purified a novel mannose binding lectin form Musca domestica pupae by affinity chromatography on Con A-Sepharose 4B and DEAE weak anion-exchange chromatography. By SDS-PAGE, MBL-1 yielded a single band with the molecular weight of 24 kDa. It was a glycoprotein detected by periodic acid-schiffs staining reaction, with 97.36% protein and 2.1% oligosaccharide. Meanwhile, the results of beta-elimination reaction, infrared spectroscopy, atomic force microscopy and protein sequencing instrument show that MBL-1 was an ellipsoidal-shaped monomer with 60-100 nm in diameter. N-glycoside bond linked oligosaccharide chain and the N-terminal blocked peptide chain. Further study suggested that MBL-1 promote the proliferation of macrophage in a concentration-dependent manner. The scanning electron microscope analysis shows that MBL-1 promoted the activation of macrophages. These results show that MBL-1 purified from Musca domestica pupae possesses immune regulation effect, serving a reference basis to develop natural immune-modulator.
Animals ; Glycoproteins ; analysis ; Houseflies ; chemistry ; Immunomodulation ; immunology ; physiology ; Macrophages ; immunology ; Mannose-Binding Lectin ; chemistry ; physiology ; Oligosaccharides ; analysis ; Pupa ; chemistry

To investigate the effect of the Ginkgo Biloba Extract (GBE) on the asthma and examine its possible mechanisms, 75 asthma patients were divided into 4 groups and the patients were respectively treated with fluticasone propionate for 2 weeks or 4 weeks, or treated with fluticasone propionate plus GBE for 2 weeks or 4 weeks. Fifteen healthy volunteers served as healthy controls. Sputum inhalation with inhaling hypertonic saline (4%-5%) was performed. Lung ventilatory function and forced expiratory volume in one second (FEV1) were measured. The numbers of different cells in induced sputum were calculated. The expression of PKCα in the cells was immunocytochemically detected and the percentages of positive cells in different cells were counted. Interleukin-5 (IL-5) in sputum supernatants was detected with enzyme-linked immunosorbent assay. The percentage of eosinophils, lymphocytes, PKCα positive inflammatory cells and the concentration of IL-5 in asthmatic patients were higher than those in the controls (P＜0.05), and the eosinophils, lymphocytes,positive expression of PKCα and the level of IL-5 were significantly decreased in asthmatic patients after they were treated with fluticasone propionate or fluticasone propionate plus GBE. However,they were still significantly higher than those of the controls. Compared to the group treated with glucocorticosteroid for 2 weeks, no significant decrease was found in the percentage of eosinophils,lymphocytes, PKCα positive inflammatory cells and the IL-5 in the supernatant of induced sputum.Compared with the group treated with glucocorticosteroid for 2 or 4 weeks, significant decrease in the same parameters was observed in the group treated with fluticasone propionate and GBE for 4 weeks. The IL-5 level in the supernatant of induced sputum was positively correlated with the percentage of PKCα-positive inflammatory cells and the percentage of eosinophils in the induced sputum in asthma patient groups respectively (n=150, r= 0.83, P＜0.01; n=150, r=0.76, P＜0.01). The FEV1 was negatively correlated with the percentage of PKCα-positive inflammatory cells and the IL-5 levels in supernatant of induced sputum in asthma patients respectively (n=150, r=-0.77,P＜0.01; n=150, r= -0.64, P＜0.01). It is concluded that GBE could significantly decrease the infiltration of inflammatory cells such as eosinophils and lymphocytes in the asthmatic airway and relieve the airway inflammation. GBE may decrease the activation of the PKCα in the inflammatory cells and thereby decrease the IL-5 level in induced sputum. GBE may be used as a complement to the glucocorticosteroid therapy for asthma.

This study summarized the determination methods and principles of 2019 novel coronavirus(severe acute respiratory syndrome coronavirus 2,SARS-CoV-2). The advantages and limitations of several methods was compared, which can provide a basis for the selection of 2019 novel coronavirus clinical diagnosis methods.
Betacoronavirus ; Clinical Laboratory Techniques ; Coronavirus Infections ; diagnosis ; Humans ; Pandemics ; Pneumonia, Viral ; diagnosis

To establish the experts consensus on the management of delirium in critically ill patients.A special committee was set up by 15 experts from the Chinese Critical Hypothermia-Sedation Therapy Study Group.Each statement was assessed based on the GRADE (Grading of Recommendations Assessment,Development,and Evaluation) principle.Then the Delphi method was adopted by 36 experts to reassess all the statements.(1) Delirium is not only a mental change,but also a clinical syndrome with multiple pathophysiological changes.(2) Delirium is a form of disturbance of consciousness and a manifestation of abnormal brain function.(3) Pain is a common cause of delirium in critically ill patients.Analgesia can reduce the occurrence and development of delirium.(4) Anxiety or depression are important factors for delirium in critically ill patients.(5) The correlation between sedative and analgesic drugs and delirium is uncertain.(6) Pay attention to the relationship between delirium and withdrawal reactions.(7) Pay attention to the relationship between delirium and drug dependence/ withdrawal reactions.(8) Sleep disruption can induce delirium.(9) We should be vigilant against potential risk factors for persistent or recurrent delirium.(10) Critically illness related delirium can affect the diagnosis and treatment of primary diseases,and can also be alleviated with the improvement of primary diseases.(11) Acute change of consciousness and attention deficit are necessary for delirium diagnosis.(12) The combined assessment of confusion assessment method for the intensive care unit and intensive care delirium screening checklist can improve the sensitivity of delirium,especially subclinical delirium.(13) Early identification and intervention of subclinical delirium can reduce its risk of clinical delirium.(14) Daily assessment is helpful for early detection of delirium.(15) Hopoactive delirium and mixed delirium are common and should be emphasized.(16) Delirium may be accompanied by changes in electroencephalogram.Bedside electroencephalogram monitoring should be used in the ICU if conditions warrant.(17) Pay attention to differential diagnosis of delirium and dementia/depression.(18) Pay attention to the role of rapid delirium screening method in delirium management.(19) Assessment of the severity of delirium is an essential part of the diagnosis of delirium.(20) The key to the management of delirium is etiological treatment.(21) Improving environmental factors and making patient comfort can help reduce delirium.(22) Early exercise can reduce the incidence of delirium and shorten the duration of delirium.(23) Communication with patients should be emphasized and strengthened.Family members participation can help reduce the incidence of delirium and promote the recovery of delirium.(24) Pay attention to the role of sleep management in the prevention and treatment of delirium.(25) Dexmedetomidine can shorten the duration of hyperactive delirium or prevent delirium.(26) When using antipsychotics to treat delirium,we should be alert to its effect on the heart rhythm.(27) Delirium management should pay attention to brain functional exercise.(28) Compared with non-critically illness related delirium,the relief of critically illness related delirium will not accomplished at one stroke.(29) Multiple management strategies such as ABCDEF,eCASH and ESCAPE are helpful to prevent and treat delirium and improve the prognosis of critically ill patients.(30) Shortening the duration of delirium can reduce the occurrence of long-term cognitive impairment.(31) Multidisciplinary cooperation and continuous quality improvement can improve delirium management.Consensus can promote delirium management in critically ill patients,optimize analgesia and sedation therapy,and even affect prognosis.