In vivo manipulation of the bleomycin biosynthetic gene cluster in Streptomyces verticillus ATCC15003 revealing new insights into its biosynthetic pathway.

Bleomycin (BLM), an important clinically used antitumor compound, and its analogs are challenging to prepare by chemical synthesis. Genetic engineering of the biosynthetic pathway in the producer strain would provide an efficient and convenient method of generating new derivatives of this complex molecule in vivo. However, the BLM producing Streptomyces verticillus ATCC15003 has been refractory to all means of introducing plasmid DNA into its cells for nearly two decades.

Diabetes is not prevented by Foxp3-transduced CD4(+)T cells under the IL-12Rbeta2 promoter control.

Our previous studies have shown that Foxp3 under the control of IFN-gamma promoter (IgammaP-Foxp3) converts pathogenic CD4(+)Th1 cells into regulatory T cells (Tregs), which control diabetes in non-obese diabetic (NOD) mice. Here, we tested the other hypothesis that transient expression of Foxp3 as controlled by the transient expression of IL-12Rbeta2 during Th1 cell derivation is sufficient to convert cells to Tregs. Foxp3, under the control of IL-12Rbeta2 promoter (Ibeta2P), was lentivirally transduced into naïve CD4(+)T cells from NOD mice.

Classification of duck hepatitis virus into three genotypes based on molecular evolutionary analysis.

The nucleotide sequences of the complete VP1, VP0, VP3, and partial 3D regions of seven duck hepatitis virus (DHV) serotype 1 (DHV-1) strains isolated in China between 2001 and 2007 and one DHV-1 strain originally obtained from ATCC were determined and compared with previously available DHV sequences in GenBank. Phylogenetic analysis on the basis of VP1 sequences demonstrated three distinct genetic groups. There was an excellent concordance among the genetic groups assigned based on the complete VP0, VP3, and the partial 3D regions.

[Levels of serum heart-type fatty acid-binding protein and its clinical significance in children with Kawasaki disease].

Objective: This study examined serum level of heart-type fatty acid-binding protein (h-FABP) in children with Kawasaki disease (KD) in order to assess its value in KD.

Methods: Forty children with KD and 30 healthy children were enrolled. Serum levels of h-FABP and cardiac troponin I (cTnI) were measured using ELISA.

Effects of Class III magnetic orthopedic forces on the craniofacial sutures of rhesus monkeys.

Introduction: The objectives of this study were to develop an intraoral intermaxillary Class III magnetic orthopedic appliance (MOA-III), to investigate the influence of Class III orthopedic forces on the craniofacial sutures of rhesus monkeys, and to elucidate the mechanism of Class III malocclusion orthopedic treatment.

Methods: Six male rhesus monkeys in the mixed-dentition stage were divided into 3 groups of 2 each: a 90-day experimental group, a 45-day experimental group, and a control group. Six craniofacial sutures were observed.

Characterization of a novel anti-DR5 monoclonal antibody WD1 with the potential to induce tumor cell apoptosis.

TNF-related apoptosis-inducing ligand (TRAIL) is a TNF family member capable of inducing apoptosis. Death receptor 5 (DR 5) is a key receptor of TRAIL and plays an important role in TRAIL-induced apoptosis. To prepare monoclonal antibodies (mAbs) against DR5, cDNA encoding soluble DR5 (sDR5) was firstly amplified by reverse transcriptase-polymerase chain reaction (RT-PCR) with specific primers, and then inserted into a prokaryotic expression vector pET-30a.

Kadsuracoccinic acids A-C, ring-A seco-lanostane triterpenes from Kadsura coccinea and their effects on embryonic cell division of Xenopus laevis.

Three new 3,4- seco-lanostanes, kadsuracoccinic acids A-C ( 1- 3), were isolated from the medicinal plant Kadsura coccinea, in addition to the known compounds kadsuric acid ( 4) and micranoic acid A ( 5). The structures of 1- 3 were elucidated by analysis of their 2D-NMR spectroscopic data. Furthermore, the relative conformation of 1 was confirmed by an X-ray crystallographic study.

Bioactive triterpene saponins from the roots of Phytolacca americana.

Five new triterpene saponins named phytolaccasaponins N-1 (1), N-2 (2), N-3 (3) N-4 (4), and N-5 (5) were isolated from the roots of Phytolacca americana together with seven known triterpene saponins (6-12). The structures of the five new saponins were established as shown in structures 1-5 on the basis of their spectroscopic data. The MDR-reversal activity of 1-12 was evaluated on the basis of the amount of calcein accumulated in MDR human ovarian cancer 2780 AD cells in the presence of each compound.

Kadsuralignans H-K from Kadsura coccinea and their nitric oxide production inhibitory effects.

One new arylnaphthalene lignan named kadsuralignan H ( 1) and three new dibenzocyclooctadiene lignans, named kadsuralignans I ( 2), J ( 3), and K ( 4), respectively, were isolated from an EtOAc fraction of the 80% acetone extract of Kadsura coccinea. The structures were elucidated on the basis of spectroscopic evidence. Compound 1 is the second arylnaphthalene lignan isolated from the Kadsura genus.

Halogen bonding as a new driving force for layer-by-layer assembly.

A new approach for fabricating a layer-by-layer polymer film was explored, which was based on the halogen bonding between poly(4-(4-iodo-2,3,5,6-tetrafluorophenoxy)-butyl acrylate) and poly(4-vinylpyridine). Layer-by-layer assembly of two polymers was confirmed by UV-vis spectroscopy and quartz crystal microbalance measurements. The interaction between the two polymers was identified as halogen bonding by X-ray photoelectron spectroscopy.

A novel two-dimensional nickel(II) coordination polymer with 1,4-bis(1,2,4-triazol-1-ylmethyl)benzene and azide ligands.

The coordination geometry of the Ni(II) atom in the title complex, poly[diazidobis[mu-1,4-bis(1,2,4-triazol-1-ylmethyl)benzene-kappa(2)N(4):N(4')]nickel(II)], [Ni(N(3))(2)(C(12)H(12)N(6))(2)](n), is a distorted octahedron, in which the Ni(II) atom lies on an inversion centre and is coordinated by four N atoms from the triazole rings of two symmetry-related pairs of 1,4-bis(1,2,4-triazol-1-ylmethyl)benzene (bbtz) ligands and two N atoms from two symmetry-related monodentate azide ligands. The Ni(II) atoms are bridged by four bbtz ligands to form a two-dimensional (4,4)-network.

Bioactive cardenolides from the stems and twigs of Nerium oleander.

Four new cardenolide monoglycosides, cardenolides N-1 (1), N-2 (2), N-3 (3), and N-4 (4), were isolated from Nerium oleander, together with two known cardenolides, 5 and 12, and seven cardenolide monoglycosides, 6-11 and 13. The structures of compounds 1-4 were established on the basis of their spectroscopic data. The in vitro anti-inflammatory activity of compounds 1-13 was examined on the basis of inhibitory activity against the induction of the intercellular adhesion molecule-1 (ICAM-1).

Bioactive polyketides from Peperomia duclouxii.

Four new compounds (1-4) were isolated along with 16 known compounds from whole plants of Peperomia duclouxii. The new structures were elucidated as 4-hydroxy-2-[(3,4-methylenedioxyphenyl)nonanoyl]cyclohexane-1,3-dione (1), 4-hydroxy-2-[(3,4-methylenedioxyphenyl)undecanoyl]cyclohexane-1,3-dione (2), 4-hydroxy-2-[(3,4-methylenedioxyphenyl)tridecanoyl]cyclohexane-1,3-dione (3), and 2-[(3,4-methylenedioxyphenyl)dodecyl]-4-hydroxy-2,3,4,6,7,8-hexahydro-2H-1-benzopyran-5-one (4), by analysis of their spectroscopic data. The known polyketides, surinone A and oleiferinone, showed cell growth inhibitory activity against the WI-38, VA-13, and HepG2 cell lines with IC50 values that ranged from 4.

Bioactive lignans from Peperomia duclouxii.

Six new lignans (1-6), along with 14 known compounds, were obtained from Peperomia duclouxii. The new structures were elucidated mainly by the analysis of their NMR and MS data. The absolute configurations of 1-6 were determined by comparing their optical rotations or CD spectra with those of known compounds.

Glycopeptide antitumor antibiotic zorbamycin from Streptomyces flavoviridis ATCC 21892: strain improvement and structure elucidation.

Zorbamycin (1, ZBM) is a glycopeptide antitumor antibiotic first reported in 1971. The partial structures of 1 were speculated on the basis of its acid hydrolysis products, but the structure of the intact molecule has never been established. The low titer of 1 from the wild-type strain, combined with its acid-instability, has so far hampered its isolation.

Bioactive pregnanes from Nerium oleander.

Three new pregnanes, 21-hydroxypregna-4,6-diene-3,12,20-trione (1), 20R-hydroxypregna-4,6-diene-3,12-dione (2), and 16beta,17beta-epoxy-12beta-hydroxypregna-4,6-diene-3,20-dione (3), were isolated from Nerium oleander, together with two known compounds, 12beta-hydroxypregna-4,6,16-triene-3,20-dione (neridienone A, 4) and 20S,21-dihydroxypregna-4,6-diene-3,12-dione (neridienone B, 5). The structures of compounds 1-3 were established on the basis of their spectroscopic data. The anti-inflammatory activity in vitro of compounds 2-4 was examined on the basis of inhibitory activity against the induction of intercellular adhesion molecule-1 (ICAM-1), and compound 4 was active.

The tallysomycin biosynthetic gene cluster from Streptoalloteichus hindustanus E465-94 ATCC 31158 unveiling new insights into the biosynthesis of the bleomycin family of antitumor antibiotics.

The tallysomycins (TLMs) belong to the bleomycin (BLM) family of antitumor antibiotics. The BLM biosynthetic gene cluster has been cloned and characterized previously from Streptomyces verticillus ATCC 15003, but engineering BLM biosynthesis for novel analogs has been hampered by the lack of a genetic system for S. verticillus.

Triterpenoids from Hippophae rhamnoides L. and their nitric oxide production-inhibitory and DPPH radical-scavenging activities.

In our investigation on the chemical constituents of Hippophae rhamnoides L., the chloroform-soluble fraction of the 80% acetone extract of branch bark was observed to inhibit nitric oxide (NO) production in a lipopolysaccharide and recombinant mouse interferon-gamma-activated murine macrophage-like cell line, RAW 264.7 cells.

Estimating the population of female sex workers in two Chinese cities on the basis of the HIV/AIDS behavioural surveillance approach combined with a multiplier method.

Objective: To estimate the size of the population of female sex workers (FSWs) on the basis of the HIV/AIDS behavioural surveillance approach in two Chinese cities, using a multiplier method.

Method: Relevant questions were inserted into the questionnaires given to two behavioural surveillance groups-female attendees of sexually transmitted disease (STD) clinics and FSWs. The size of the FSW population was derived by multiplying the number of FSWs in selected STD clinics during the study period by the proportion of FSW population who reported having attended the selected STD clinics during the same period.

Bioactive guaianolides from siyekucai (Ixeris chinensis).

Two new guaianolides, named chinensiolides D (5) and E (6), were isolated from Ixeris chinensis Nakai, and their structures were determined to be 10alpha-hydroxy-3-oxoguaia-11(13)-eno-12,6alpha-lactone (5) and 10alpha-hydroxy-3beta-O-[2,6-di(p-hydroxyphenylacetyl)-beta-glucopylanosyl]guaia-4(15),11(13)-dieno-12,6alpha-lactone (6). The first isolation of (11S)-10alpha-hydroxy-3-oxoguaia-4-eno-12,6alpha-lactone (4) from natural sources and its characterization are also reported. Chinenciolide E (6) showed significant growth inhibitory activity toward VA-13 malignant lung tumor cells (IC50 = 0.

Taraxasterane- and ursane-type triterpenes from Nerium oleander and their biological activities.

Two new taraxasterane-type triterpenes, 20beta,28-epoxy-28alpha-methoxytaraxasteran-3beta-ol (1) and 20beta,28-epoxytaraxaster-21-en-3beta-ol (2), were isolated from an ethyl acetate extract of the leaves of Nerium oleander, together with ursane-type triterpenes, 28-nor-urs-12-ene-3beta,17beta-diol (3) and 3beta-hydroxyurs-12-en-28-aldehyde (4). The structures of 1 and 2 were established on the basis of their spectroscopic data. Anti-inflammatory activity of 1-4 was examined on the basis of inhibitory activity against the induction of intercellular adhesion molecule-1 (ICAM-1).

Cloning and expression analysis of SKn-type dehydrin gene from bean in response to heavy metals.

A heavy metal responsive gene PvSR3 (GenBank accession number U54703) encoding an acid dehydrin was isolated from a mercuric chloride-treated bean (Phaseolus vulgaris L.) leaf cDNA library by differential screening using cDNAs derived from treated and untreated plants. The PvSR3 cDNA is 981-bp long and has a 606-bp open-reading frame with a 202-residue-deduced amino acid sequence.

Bioactive dibenzylbutyrolactone and dibenzylbutanediol lignans from Peperomia duclouxii.

Six new dibenzylbutyrolactone (6-11) and two new dibenzylbutanediol lignans (12, 13) were obtained from Peperomia duclouxii. The structures were elucidated mainly by the analysis of NMR and MS data. The anticancer activity against a normal (WI-38) and a simian virus 40-transformed human lung fibroblast cell (VA-13) and a hepatoma G2 cell (HepG2) and the MDR reversal activity of the isolated compounds were examined.

Inhibition of cellular proliferation by diterpenes, topoisomerase II inhibitor.

We examined the effects of 12 terpene compounds derived from the roots of Euphorbia kansui on the proliferative activity of Xenopus embryo cells. Eight of these compounds showed significant inhibition of cellular proliferation even at low concentrations, while four of them needed to be present at higher concentrations to inhibit cellular proliferation. In order to define the mechanism of inhibition of cellular proliferation by these compounds, the effects of diterpene compounds on the activity of topoisomerase II were measured.

Lignans from the roots of Wikstroemia indica and their DPPH radical scavenging and nitric oxide inhibitory activities.

In our investigation of in vitro anti-allergic screening of medicinal herbal extracts, the ethyl acetate extract of the root of Wikstroemia indica was observed to inhibit nitric oxide (NO) production in a lipopolysaccharide (LPS) and recombinant mouse interferon-gamma (IFN-gamma) activated murine macrophage-like cell line, RAW 264.7. Fractionation of the active extract led to the isolation of two new lignan dimer bis-5,5-nortrachelogenin (1) and bis-5,5'-nortrachelogenin (2), and three known lignans.