Chemical analysis and in vitro antimicrobial effects and mechanism of action of Trachyspermum copticum essential oil against Escherichia coli

Objective To find a natural plant essential oil (EO) with excellent antimicrobial effects on food-borne bacteria and to explore the mechanism of its antimicrobial function against Escherichia coli (E. coli). Methods The antimicrobial activity of seven EOs against Gram-negative E. coli ATCC 8739 and Gram-positive Staphylococcus aureus ATCC 6538 was investigated using agar disk diffusion method, and the minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) of each EO was determined using the broth dilution method. The chemical composition of the Trachyspermum copticum (T. copticum) EO was analyzed using gas chromatography–mass spectrometry (GC/MS). In order to explore the mechanism of the antimicrobial action, 1 MIC and 2 MIC of T. copticum EO was added to a suspension of E. coli, the growth curve and the scanning electron microscopy (SEM) analysis of E. coli, and the release of cell constituents and protein and potassium ions from the bacterial cell were measured. Results The T. copticum EO had the best antimicrobial activity against the test bacteria, and 10 compounds accounting for 94.57% of the total oil were identified, with the major components being thymol (46.22%), p-cymene (19.03%), and γ-terpinene (22.41%). The addition of 1 MIC that T. copticum EO significantly inhibited the growth of E. coli and increased the release of cell constituents and protein and potassium ions from the bacterial cells. Scanning electron micrographs showed that T. copticum EO caused most of the E. coli cell membranes to collapse and rupture, leading to cell death. Conclusions These results indicate that T. copticum EO is a good natural antimicrobial agent for food-borne pathogens.

Chemical analysis and in vitro antimicrobial effects and mechanism of action of Trachyspermum copticum essential oil against Escherichia coli

OBJECTIVE@#To find a natural plant essential oil (EO) with excellent antimicrobial effects on food-borne bacteria and to explore the mechanism of its antimicrobial function against Escherichia coli (E. coli).@*METHODS@#The antimicrobial activity of seven EOs against Gram-negative E. coli ATCC 8739 and Gram-positive Staphylococcus aureus ATCC 6538 was investigated using agar disk diffusion method, and the minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) of each EO was determined using the broth dilution method. The chemical composition of the Trachyspermum copticum (T. copticum) EO was analyzed using gas chromatography-mass spectrometry (GC/MS). In order to explore the mechanism of the antimicrobial action, 1 MIC and 2 MIC of T. copticum EO was added to a suspension of E. coli, the growth curve and the scanning electron microscopy (SEM) analysis of E. coli, and the release of cell constituents and protein and potassium ions from the bacterial cell were measured.@*RESULTS@#The T. copticum EO had the best antimicrobial activity against the test bacteria, and 10 compounds accounting for 94.57% of the total oil were identified, with the major components being thymol (46.22%), p-cymene (19.03%), and γ-terpinene (22.41%). The addition of 1 MIC that T. copticum EO significantly inhibited the growth of E. coli and increased the release of cell constituents and protein and potassium ions from the bacterial cells. Scanning electron micrographs showed that T. copticum EO caused most of the E. coli cell membranes to collapse and rupture, leading to cell death.@*CONCLUSIONS@#These results indicate that T. copticum EO is a good natural antimicrobial agent for food-borne pathogens.

Effect of Norcantharidin on Hematopoietic Function in Leucopenia Model Rat Induced by Cyclophosphamide / 中国实验血液学杂志

<p><b>OBJECTIVE</b>To explore the effect and mechanism of norcantharidin (NCTD) on hematopoiesis function in leucopenia model rat induced by cyclophosphamide (CTX).</p><p><b>METHODS</b>Leucopenia model was replicated in SD rat with cyclophosphamide(CTX) and model animal was treated with NCTD. Peripheral blood and bone marrow tissue samples were collected from the rats in each experimental group. Peripheral white blood cells (WBC) were counted and analyzed by automatic blood cell analyzer. Histopathologic changes of the biopsied bone marrow tissues were observed by histopathological techniques. The cell cycle and apoptosis rate of bone marrow cells were detected by flow cytometry. Immunohistochemical method was applied to observe the expression of apoptosis-related proteins BCL-2 and BAX in bone marrow.</p><p><b>RESULTS</b>After NCTD treatment in model rats, the WBC count of peripheral blood obviously increased, the cell structure of bone tissue significantly recovered, NCTD could promote the cell proliferation and cycle changes of bone marrow cells, inhibit the bone marrow cell apoptosis and necrosis induced with CTX, up-regulate the expression of apoptosis-related protein BCL-2 and downregulated the BAX.</p><p><b>CONCLUSION</b>NCTD can stimulate the bone marrow hematopoiesis and promote recovery of peripheral white blood cell level in the leukopenia model induced by CTX, and its mechanism may be related with NCTD regulating bone marrow cell cycle and with NCTD inhibiting cell apoptosis.</p>

Effect of hypoxia on the proliferation and hypoxia inducible factor-1α expression in human leukemia HL-60 cells / 南方医科大学学报

<p><b>OBJECTIVE</b>To explore the effects of hypoxia on the proliferation of human leukemia HL-60 cells and the cellular expression of hypoxia inducible factor-1α (HIF-1α).</p><p><b>METHODS</b>Human acute myeloid leukemia HL-60 cells with exponential growth in routine culture were exposed to 50, 200, 400, 800 µmol/L CoCl(2) to mimic hypoxic conditions. At 24, 48, and 72 h, the cells were collected for morphological observation, MTT assay, and real-time quantitative PCR for HIF-1α mRNA expression.</p><p><b>RESULTS</b>Compared with the cells without CoCl(2) treatment, the cells with CoCl(2) exposure exhibited obvious morphological changes and a significant growth inhibition which increased with CoCl(2)concentration and exposure time. At low concentrations (50-200 µmol/L), CoCl(2) treatment caused a dose- and time-dependent enhancement of HIF-1α expression in HL-60 cells.</p><p><b>CONCLUSION</b>Hypoxia mimicked by CoCl(2) exposure significantly inhibits the proliferation of HL-60 cells, and at the non-toxic doses, CoCl(2) dose- and time-dependently increases the expression of HIF-1α. The mimicked hypoxic conditions do not cause differentiation of HL-60 cells.</p>

Clinical observation on auxiliary treatment of hormone dependence dermatitis by shufeng liangxue decoction / 中国中西医结合杂志

<p><b>OBJECTIVE</b>To study the clinical efficacy of Shufeng Liangxue Decoction (SLD) in treating hormone dependence dermatitis (HDD).</p><p><b>METHODS</b>One hundred and sixteen patients with HDD were randomly assigned to two groups. Both were treated with symptomatic Western medical therapy, including oral taken of loratadine 10 mg, and intravenous injection of 10% calglucon 10 mL and vitamin C 3.0 g adding in 20 mL 50% glucose, once per day, and to the test group, one dose of SLD consisting of imperata rhizome 30 g, rehmannia root 30 g, moutain bark 15 g, schizonepeta spike 15 g, divaricate saposhnikovia root 10 g, scutellaria root 15 g, forsythia fruit 15 g, cape-jasmine fruit 10 g, red peony root 10 g, white-stiff silkworm 10 g, broom cypress fruit 15 g, Indian bread 15 g and licorice root 10 g, was given every day by decocting with water. The course of treatment was 4 weeks. Symptoms of patients, including redden-swollen skin, capillary dilatation, inflammatory papula, itching and other discomfort sensation (pain, burning, dry, buckled) were scored before and after treatment according to their severity. The efficacy was evaluated by the change in scores of symptoms, the adverse reactions occurring in the therapeutic course and the relapse rate after treatment were observed as well.</p><p><b>RESULTS</b>The cure-obvious effective rate was 76.32% in the test group and 42.50% in the control group; the total effective rate in them was 94.74% and 77.50% respectively, all showing significant difference (P < 0.05) between groups. In the test group, slight diarrhea appeared in 5 patients and slight nausea with upper abdominal discomfort in 3; while in the control group, slight somnolence appeared in 2, but all these adverse reactions did not affect the treatment. A 3-month follow-up study showed that the relapse rate in the test group was significantly lower than that in the control group (16.00% vs. 42.50% , P < 0.01).</p><p><b>CONCLUSION</b>SLD is effective and safe in treating HDD, with the efficacy better and relapse rate lower than those of treatment with Western medicine alone.</p>

Relationship of survival rate, hematoma thickness and midline shift in patients with acute subdural hematomas / 中华外科杂志

<p><b>OBJECTIVE</b>To estimate outcomes of patients with acute subdural hematomas by analysing the hematoma thickness, midline shift and the differences between them.</p><p><b>METHODS</b>Ninety-five patients with acute subdural hematoma were retrospectively studied by calculating hematoma thickness, midline shift and their difference with a statistical analysis of Kaplan-Meier, Wilcoxon-Mann-Whitney U test.</p><p><b>RESULTS</b>The hematoma thickness ranged from 5.0 to 40.0 mm and midline shift was from 0 to 35.0 mm. Among these patients, 51% died and 49% survived after surgery. 18 patients (19%) showed good or satisfactory results. Kaplan-Meier analysis proved that the survival for patients with hematoma thickness approximately equal to l7 mm and a midline shift 15 mm or whose midline shift exceeded hematoma thickness by 2.2 mm, the survival rate was 50%. Glasgow outcome scale scores were correlated significantly with these parameters.</p><p><b>CONCLUSION</b>The hematoma thickness, midline shift and their difference provided a database from which criteria could be derived, that is crucial for prognosis estimation.</p>