In this study, 101 strains of bacteria were isolated from arct ic water and sediment samples. The methanol extracts of the fermented broth prod uced by these strains were screened in vitro for anti-tumor activity on mou se tsFT210 cells using the method of flow cytometry, and screened for antibacter ial activity by the method of paper disk diffusion. The result showed that one strain exhibited anti-tumor activity and eight strains had antibacterial activ ity. The stability of the antibacterial components produced by strain AR084 an d its optimum medium were also studied. The research indicated that arctic bac teria had potential application in pharmaceutics.

Objective The cytotoxic microbial strains isolated from the deep ocean water and sediments were screened,and the secondary metabolites of bioactive fungus c2b were investi- gated.Methods Active bioactive microbial strains were screened using brine shrimp and chro- nic medulla leucocythemia leukocythemia(K562)cell line.The cytotoxic components of fun- gus c2b were isolated by bioassay-guided fractionation and solvent extraction,silica gel col- umn chromatography and preparative HPLC.Their structures were established by pbysico- chemical properties and spectral analyses.The cytotoxicities of compounds were evaluated by SRB method.Results and Conclusion Twenty-nine strains of fungi were isolated.Among them,seven strains showed cytotoxic activities.Six compounds(1～6)were isolated and i- dentified as N-acetyl histamine(1),chrysogine(2),ergosterol peroxide(3),5,8-epidioxy- 24-methylcholesta-6,22-dien-3?-ol(4)cerevisterol(5)and(4E,8E)-N-[(2'R,3'E)-2'-hy- droxy-3'-hexadecenoyl]-1-O-?-D-glycopyranosyl-9-methyl-4,8-sphingadiene(6),respective- ly.Compound 3 and 4 showed median cytotoxicity.

A novel hemiacetal, citrinacetal (1) was isolated from a marine-derived fungus Penicillium citrinum by column chromatography on silica gel, Sephadex LH-20 and semi-preparative HPLC. Its structure and stereochemistry was established on the basis of HR-ESI-MS, 1D and 2D NMR spectroscopic methods. The NMR spectrum showed this compound exists in solution as a mixture of two stereoisomers. The cytotoxic effect of compound 1 was evaluated in A-549, HL-60, HeLa, and K562 cancer cell lines. However, compound 1 only displayed weak cytotoxic activity on HL-60 cell, with IC50 value 77.4 micromol x L(-1).
Acetals ; chemistry ; isolation & purification ; pharmacology ; Antineoplastic Agents ; chemistry ; isolation & purification ; pharmacology ; Chromatography, High Pressure Liquid ; HL-60 Cells ; HeLa Cells ; Humans ; K562 Cells ; Magnetic Resonance Spectroscopy ; Molecular Conformation ; Molecular Structure ; Penicillium ; chemistry ; Spectrometry, Mass, Electrospray Ionization

OBJECTIVETo investigate the growth and development of brain derived neurophic factor(BDNF)-positive neurons in the frontal lobe of human fetus.

METHODSThe expression of the BDNF-positive neurons in the frontal lobe of human fetus in the 2(nd),3(rd),and 4(th) month of gestation were observed with the streptavidin-biotin-complex/immunoperoxidase(SABC)method.

RESULTSBy the second month of gestation,BDNF-positive neurons were seen in the subventricular layer of the frontal lobe of cerebellum.By the third month of gestation,BDNF-positive neurons in the central layer were in various shapes,with big nucleus,less cytoplasm,and small processes.By the fourth month of gestation,BDNF-positive neurons in the central layer grew larger in size,cytoplasm increased,the BDNF-positive expression was enhanced with deeper dyeing,and the nerve fibers and particles were distributed between neurons;also,the BDNF-positive neurons were seen in the marginal layer of the frontal lobe of cerebrum.

CONCLUSIONBDNF-positive neurons may participate in the early development of the frontal lobe of cerebrum of human fetus.

Brain-Derived Neurotrophic Factor ; metabolism ; Fetus ; metabolism ; Frontal Lobe ; embryology ; Humans ; Neurons ; cytology ; metabolism

Objective To observe and explore the effect and clinical value of percutaneous electrical stimulation on nerve regeneration after end-to-side neurorrhaphy in rats. Methods Thirty-two SPF male S-D rats were randomly divided into four groups ( n = 8 ): group A, the normal control group; group B, with end to end neurorrhaphy of musculocutaneous nerve injury matched to the ulnar nerve; group C, with end to side neurorrhaphy of musculocutaneous nerve injury matched to the ulnar group; and group D, with end to side neurorrhaphy of musculocutaneous nerve injury matched to the ulnar nerve plus postoperative transcutaneous electrical stimulation ( 30 min per day for 6 weeks ) . Electromyography, postoperational nerve conduction velocity, the histological and ultrastructural changes of the nerve fibers were examined, and NF-200 expression in frozen sections was observed using imunohistological staining, to assess the recovery of muscle strength of the diseased side limb and the neuroregeneration in the rats after treatment. Results The amplitude and conduction velocity of the groups C and D were lower than that of the group A, the latency was higher than that of the group A, while the amplitude and conduction velocity of the group D were lower than that of the group C,and the latency was higher than that of the group C. The wet weight ratio of the biceps brachii muscle and the cross-sectional area of muscle fibers in the groups B, C and D were lower than those in the group A, and the recovery of muscle in the group C was the worst. The expression of NF-200 in the rats of groups B, C and D was significantly lower than that in the group A, and the expression of NF-200 in the group D was significantly higher than that in the group C, but still significantly less than that in the group B ( P < 0. 05 ) . Electron microscopy showed mature myelinated fibers in the group B, whereas unmyelinated fibers were the main component and the myelin sheath was poorly developed in the group C. The myelin regeneration in the group D was better than that in the group C, but still some unmyelinated nerve fibers were seen. Conclusions The percutaneous electrical stimulation can effectively promote nerve axonal regeneration and can delay the atrophy of the target muscle after end-to-side neurorrhaphy. Though there is difference compared with the end-to-end neurorrhaphy, the end-to-side neurorrhaphy is still an effective method in clinical repair of peripheral nerve injury.

A new sesquiterpene hydroquinone (1) was isolated from a deep sea sediment derived fungus, Phialocephala sp.. Its structure and stereochemistry were established on the basis of spectroscopic data and optical rotation. This compound was tested for cytotoxicity against P388 (murine leukemia cell) and K562 (human leukemia cell) cell lines, and displayed strong cytotoxic effects with IC50 value of 0.16 and 0.05 micromol x L(-1), separately.
Animals ; Antineoplastic Agents ; chemistry ; isolation & purification ; pharmacology ; Ascomycota ; chemistry ; Cell Line, Tumor ; Cell Survival ; drug effects ; Humans ; Hydroquinones ; chemistry ; isolation & purification ; pharmacology ; Inhibitory Concentration 50 ; K562 Cells ; Leukemia P388 ; pathology ; Mice ; Molecular Structure

BACKGROUNDDespite extensive research, the mechanism of immature dendritic cells (DCs) induced immune hyporesponsiveness remains incompletely understood.

METHODSRecipient DCs from C3H mouse bone marrow cells were incubated with donor antigen from splenic lymphocytes of C57BL/6 mouse; these DCs were transfected with CD80/86 specific siRNA using lentiviral vectors. Flow cytometry was used to evaluate expression of CD80/86 on the antigen-pulsed recipient DCs. Immune regulatory activity was examined by mixed lymphocyte reaction, in which irradiated DCs were cultured with C3H spleen T cells. After the reaction, interleukin (IL)-2, IL-4, IL-10, and interferon (INF)-γ levels of mixed lymphocyte reaction culture supernatant were measured by enzyme-linked immunosorbent assay. The apoptotic T lymphocytes were identified by Annexin V and CD3 staining.

RESULTSThere was a significant inhibition of CD80/86 expression in DCs transfected with CD80/86 lentiviral vectors compared with the control groups (P < 0.05), indicating the specificity of RNA interference. Enzyme-linked immunosorbent assay results showed a significant reduction of INF-γ, IL-2 and IL-10 in the CD80/86 lentivirus transfected group compared to the control groups (P < 0.05). There was no significant difference in IL-4 levels between the groups (P > 0.05). We also showed that CD80/86 low DCs loaded with alloantigen (1) stimulated low T cell proliferative responses via the indirect recognition pathway and (2) enhanced apoptotic activity (P < 0.05) in co-cultured T cells.

CONCLUSIONSLentiviral vector transfection can effectively and specifically knock down target genes in DCs. The CD80/86 low DCs may show tolerogenic activity via induction of T-cell apoptosis, thereby modulating the activity of recipient-derived DCs. The use of this approach may potentially be clinically applicable.

Animals ; Apoptosis ; B7-1 Antigen ; genetics ; physiology ; B7-2 Antigen ; genetics ; physiology ; Dendritic Cells ; immunology ; Lentivirus ; genetics ; Lymphocyte Activation ; Mice ; Mice, Inbred C3H ; Mice, Inbred C57BL ; RNA Interference ; T-Lymphocytes ; cytology ; immunology

OBJECTIVE: To investigate the cytotoxic effect and its mechanism of the micromolecule compound on the leukemia cells. METHODS: The cytotoxic effects of 28 Nilotinib derivatives on K562, KA, KG, HA and 32D cell lines were detected by MTT assays, and the compound Nilo 22 was screen out. Cell apoptosis and cell cycle on leukemia cells were detected by flow cytometry. The effect of compound screened out on leukemogenesis potential of MLL-AF9 leukemia mice GFP RESULTS: Nilo 22 serves as the most outstanding candidate out of 28 Nilotinib derivatives, which impairs leukemia cell lines, but spares normal hematopoietic cell line. Comparing with Nilotinib, Nilo 22 could induce the apoptosis of GFP CONCLUSION Nilo 22 shows a significant cytotoxic effect on mice and human leukemia cells, especially for drug resistance cells. Nilo 22 is a promising anti-leukemia agent to solve the common clinical problems of drug resistance and relapse of leukemia.
Animals ; Apoptosis/drug effects* ; Cell Cycle/drug effects* ; Cell Line, Tumor ; Humans ; Leukemia ; Mice ; Myeloid-Lymphoid Leukemia Protein/genetics* ; Telomerase/metabolism* ; Telomere/metabolism*