Purpose　The aim is to develop a synthesis method of the silver carboxymethyl chitosan and to study its bacteriostasis to Staphlococcus aureus(S.aureus),Pseudomonas aeruginusa(P.aeruginusa),Escherichia Coli(E.coli),Klebsiella pneumoniae(K.pneumoniae) and Proteus vulgaris(P.vulgaris).Methods　Chitosan was modified by way of chemistry.The structure analysis of its derivate was analysed by infra-red absorption spectroscopy,using methods of dilution and concavering to study the bacteriostasis to some ordinary bacteria which cause infection in burn.Results　The infra-red spectragram of the derivate showed the chitosan had been modified by chloroacetic acid.When the concentrationl of silver carboxymethyl chitosan was 1.028 mg/ml and the concentration of the five bacteria were 104CFU/ml，the rate of bacteriostasis was 88%、80.2%、75.3% to S.aureus、P.aeruginusa and E.coli respectively.The MIC of silver carboxymethyl chitosan was similar to that of AgNO3 when they act on S.aureus and P.aeruginusa,but the former was lower than later when acting on E.coli.Conclusion　Silver carboxymethyl chitosan could inhibit some bacteria which caused infection in burn.It was a novel pharmaceutical in preventing and curing burn infection.

OBJECTIVE Bergapten (BG), is a furanocoumarin derived from herbal and citrus extracts can act as antioxidant and selective anticancer agents.The current study aimed to investigate whether bergapten would attenuate immunosenescence and to exploreits immunomodulatory effects on immune responses in D-galactose-induced aging BALB/c mice.METHODS Firstly,mice were given D-galactose(180 mg·kg-1)subcutaneous injections for 30 d.To evaluate the establishment of the aging-related effect in mice, serum samples of BALB/c mice were collected from tail vein. Aging BALB/c mice were freely divided into three groups: negative control group received 1% Tween 80 solution only, named D-gal group. Positive groups were received BG administration at the dose of 20 and 100 mg·kg-1, named D-gal+BG(20)group and D-gal+BG(100)group,respectively.Effects of bergapten on T lympho-cyte proliferation and flow cytometry were assessed by using the splenic cell suspension. Enzyme linked immunospot kits were used to quantitatively determine interferon-γ(IFN-γ)and interleukin-4(IL-4) levels of the isolated serum. Immunophenotype was determined by using mixture of antibodies includ-ing anti-CD3,anti-CD4,and anti-CD8.RESULTS Bergapten(20 mg·kg-1)therapy can modulate immu-nity against viral epidemics and attenuate aging-induced immune deficiency(P<0.01),which was correlat-ed with the decline in the activation of the Th and Tc responses in D-galactose induced aging BALB/c mice.According to the in vivo results,bergapten exposure up-regulated the secretion of IFN-γ and IL-4 in T-helper 1(Th1)and T helper 2(Th2)cells(P<0.05,P<0.01).Additionally,BG(20 mg·kg-1)restored antigen-specific CD4+and CD8+T cells in aging models (P<0.05, P<0.01), which may help to curing chronic infections. CONCLUSION The beneficial effect of bergapten in D-galactose induced aging BALB/c mice may be due to the Th and Tc responses activation.

Objective To explore the effect of ginsenoside Rg1 on leukemia stem cells through comparing the biological senescence characteristics of HSCs in the patients with leukemia and healthy people,and provide new ideas and methods for leukemia prevention and treatment.Methods Fifteen cases of normal bone marrow in normal group and sixteen cases of chronic myeloid leukemia in leukemia group were divided into control group and Rg1 group,respectively.The control group used the conventional culture.The Rg1 group used the culture system with 10 μg/mL ginsenoside Rg1,other conditions were the same as control group.The bone marrow mononuclear cell of all groups were extracted after 2 days,and the CD34 +/CD38-cells population was isolated and purified by immunomagnetic adsorption cell sorting(MACS).The purity of the cells and cell cycles phase were detected by flow cytometry.Cell viability was detected by trypan blue staining.The percentage of positive cells was detected by SA-β-gal staining.CCK-8 detected the CD34 +/CD38-proliferation ability of each group.Results The ratio of CD34 +/CD38-cell population was (1.76 ± 0.34) ％ in every 1 × 106 BMNCs before sorting;the proportion of CD34 +/CD38-cell population per 1 × 106 cells after immunomagnetic sorting was (91.15 ± 2.41)％.The positive rate of SA-β-gal staining in human bone marrow CD34 +/CD38-cells of leukemia Rg1 group was significantly higher than that in leukemia control group,the difference was not significant (P ＞ 0.05);meanwhile there was no significant difference between normal control group and normal Rg1 group,but higher than that in leukemia control group,the difference was significant(P ＜ 0.05).CCK-8 results showed that the proliferation of CD34 +/CD38-cells was significantly increased in leukemia control group than those in the other groups.The survival rate of CD34 +/CD38-cells in human bone marrow was 99.1％ in all groups.Cell cycle phase results showed that the G1 arrest of CD34 +/CD38-cells in leukemia control group was significantly lower than those in the other three groups.Conclusion CD34 +/CD38-cells in chronic myeloid leukemia patients may be caused by some chronic myeloid leukemia.Ginsenoside Rg1 can effectively delay the process of aging.

BACKGROUNDGambogic acid is a pure active compound isolated from the traditional Chinese medicinal plant gamboge (Garcinia morella Desv.). Based on the preliminary results of a phase I study, this phase IIa study compared the efficacy and safety of different dosage schedules of gambogic acid in patients with advanced malignant tumors.

METHODSPatients with advanced or metastases cancer who had not received any effective routine conventional treatment or who had failed to respond to the existing conventional treatment were randomly assigned to receive either 45 mg/m(2) gambogic acid intravenously from Days 1 to 5 of a 2-week cycle (Group A), or 45 mg/m(2) every other day for a total of five times during a 2-week cycle (Group B). The primary endpoint was objective response rate (ORR).

RESULTSTwenty-one patients assigned to Group A and 26 to Group B were included in the final analysis. The ORRs were 14.3% in Group A and 0% in Group B. It was not possible to analyze the significant difference because one of the values was zero. The disease control rates (DCRs) were 76.2% in Group A and 61.5% in Group B (P = 0.0456). The observed adverse reactions were mostly Grades I and II, and occurred in most patients after administration of the trial drug. There was no significant difference in the incidence of adverse reactions between the two arms.

CONCLUSIONSThe preliminary results of this phase IIa exploratory study suggest that gambogic acid has a favorable safety profile when administered at 45 mg/m(2). The DCR was greater in patients receiving gambogic acid on Days 1 - 5 of a 2-week cycle, but the incidence of adverse reactions was similar irrespective of the administration schedule.

Adult ; Aged ; Antineoplastic Agents, Phytogenic ; administration & dosage ; Female ; Humans ; Injections ; Male ; Middle Aged ; Neoplasms ; drug therapy ; Xanthones ; administration & dosage ; adverse effects

Objective:Trigeminal neuralgia(TN)is a severe chronic neuropathic pain that mainly affects the distribution area of the trigeminal nerve with limited treating efficacy.There are numerous treatments for TN,but currently the main clinical approach is to suppress pain by carbamazepine(CBZ).Brain-derived neurotrophic factor(BDNF)is closely related to chronic pain.This study aims to determine the effects of CBZ treatment on BDNF expression in both the trigeminal ganglion(TG)and serum of TN via a chronic constriction injury of the infraorbital nerve(ION-CCI)rat model. Methods:The ION-CCI models were established in male Sprague-Dawley rats and were randomly divided into a sham group,a TN group,a TN+low-dose CBZ treatment group(TN+20 mg/kg CBZ group),a TN+medium-dose CBZ treatment group(TN+40 mg/kg CBZ group),and a TN+high-dose CBZ treatment group(TN+80 mg/kg CBZ group).The mechanical pain threshold in each group of rats was measured regularly before and after surgery.The expressions of BDNF and tyrosine kinase receptor B(TrkB)mRNA in TGs of rats in different groups were determined by real-time PCR,and the expression of BDNF protein on neurons in TGs was observed by immunofluorescence.Western Blotting was used to detect the protein expression of BDNF,TrkB,extracellular regulated protein kinases(ERK),and phospho-extracellular regulated protein kinases(p-ERK)in TGs of rats in different groups.The expression of BDNF in the serum of rats in different groups was detected by enzyme-linked immunosorbent assay(ELISA). Results:The results of mechanical pain sensitivity showed that there was no significant difference in the mechanical pain threshold in the right facial sensory area of the experimental rats in each group before surgery(all P>0.05).From the 3rd day after operation,the mechanical pain threshold of rats in the TN group was significantly lower than that in the sham group(all P<0.01),and the mechanical pain threshold of rats in the TN+80 mg/kg CBZ group,the TN+40 mg/kg CBZ group,and the TN+20 CBZ mg/kg group was higher than that in the TN group(all P<0.05).The BDNF and TrkB mRNA and protein expressions in TGs of rats in the TN group were higher than those in the sham group(all P<0.05),and those in the TN+80 mg/kg CBZ group,the TN+40 mg/kg CBZ group,and the TN+20 mg/kg CBZ group were lower than the TN group(all P<0.05).The p-ERK levels in TG of rats in the TN+80 mg/kg CBZ group,the TN+40 mg/kg CBZ group,and the TN+20 mg/kg CBZ group were significantly decreased compared with the TN group(all P<0.05).The BDNF and neuron-specific nuclear protein(NeuN)were mainly co-expressed in neuron of TGs in the TN group and they were significantly higher than those in the sham group(all P<0.05).The co-labeled expressions of BDNF and NeuN in TGs of the TN+ 80 mg/kg CBZ group,the TN+40 mg/kg CBZ group,and the TN+20 mg/kg CBZ group were lower than those in the TN group(all P<0.05).The results of ELISA showed that the level of BDNF in the serum of the TN group was significantly higher than that in the sham group(P<0.05).The levels of BDNF in the TN+80 mg/kg CBZ group,the TN+40 mg/kg CBZ group,and the TN+20 mg/kg CBZ group were lower than those in the TN group(all P<0.05).Spearman correlation analysis showed that the BDNF level in serum was negatively correlated with mechanical pain threshold(r=-0.650,P<0.01). Conclusion:CBZ treatment can inhibit the expression of BDNF and TrkB in the TGs of TN rats,reduce the level of BDNF in serum of TN rats and the phosphorylation of ERK signaling pathway,so as to inhibit TN.The serum level of BDNF can be considered as an indicator for the diagnosis and prognosis of TN.

The COVID-19 pandemic is still ongoing in the world, the risk of COVID-19 spread from other countries or in the country will exist for a long term in China. In the routine prevention and control phase, a number of local COVID-19 epidemics have occurred in China, most COVID-19 cases were sporadic ones, but a few case clusters or outbreaks were reported. Winter and spring were the seasons with high incidences of the epidemics; border and port cities had higher risk for outbreaks. Active surveillance in key populations was an effective way for the early detection of the epidemics. Through a series of comprehensive prevention and control measures, including mass nucleic acid screening, close contact tracing and isolation, classified management of areas and groups at risk, wider social distancing and strict travel management, the local COVID-19 epidemics have been quickly and effectively controlled. The experiences obtained in the control of the local epidemics would benefit the routine prevention and control of COVID-19 in China. The occurrence of a series of COVID-19 case clusters or outbreaks has revealed the weakness or deficiencies in the COVID-19 prevention and control in China, so this paper suggests some measures for the improvement of the future prevention and control of COVID-19.
COVID-19/prevention & control* ; China/epidemiology* ; Contact Tracing ; Epidemics/prevention & control* ; Humans ; Pandemics/prevention & control* ; SARS-CoV-2