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Two new naphthalene-chroman coupling derivatives, cladonaphchroms A (1) and B (2), along with four known compounds (3-6) were obtained from EtOAc extract of the mangrove-derived fungus Cladosporium sp. JJM22. Their structures were elucidated by detailed analysis of comprehensive spectroscopic data. Compounds 1 and 2 exhibit antibacterial or antifungal activities.

Two novel aporphine-derived alkaloids, aporaloids A and B (1 and 2), together with eight known biogenetically related alkaloids (3−10), two known isoquinoline alkaloids (3 and 4), and six known aporphinoid alkaloids (5–10) were isolated from the stems of Fissistigma glaucescens. Their structures were elucidated using comprehensive spectroscopic methods. Compounds 1 and 2 represent the rare example of a six-membered lactone ring aporphine-derived alkaloids from natural products. The inhibitory activities of all compounds against four cancer cell lines were evaluated. Aporaloids A and B (1 and 2) showed broad spectrum cytotoxic activities.

Three new phenylpropanoid derivatives, dasymaroacid A (1), dasymaroesters B and C (2 and 3), and one new polyoxygenated 6H-dibenzo[b,d]pyran-6-one derivative dasymarolactone D (4), together with seven known compounds (5-11), were isolated from the stems of Dasymaschalon rostratum Merr. Compounds 1 and 2 are unusual phenylpropanoid derivatives with a polymethyl substituted cyclopentene conjugated diketone as a substituent, and 3 is a unique cinnamic acid detective with a polymethyl substituted cyclohexene conjugated triketone as a substituent. Their structures were elucidated by extensive spectroscopic methods and chemical method, and 4 was further confirmed by the single crystal X-ray diffraction method. Compounds 1-4 and 7 showed weak anti-HIV-1 activities with EC50 values ranged from 16.44 to 25.91μM.

Three new methylated Δ8-pregnene steroids, stemphylisteroids A–C (1–3) were isolated from the medicinal plant Polyalthia laui-derived fungus Stemphylium sp. AZGP4-2. Their structures were elucidated by the detailed analysis of comprehensive spectroscopic data. The absolute configuration of 1 was determined by X-ray crystallographic analysis. Compound 1 show antibacterial activity against Escherichia coli with the MIC value of 6.25 μg/mL, and 2 exhibited a broad spectrum of antibacterial activities against six pathogenic bacteria with the MIC values ranging from 12.5 to 50 μg/mL. The discovery of three methylated Δ8-pregnene steroids 1–3 are a further addition to diverse and complex array of methylated steroids.

In an effort to identify novel, small molecules which can affect the proliferation of lung cancer cells, F-01A, a polyether antibiotic isolated from the fermentation broth of Streptomyces was tested.F-01A was tested for its antitumor properties on the lung cancer cell line SPC-A-1, at six doses (0.1, 0.5, 1, 2.5, and 5 μmol·L(-1)), using various cellular assays. Cell viability was measured by the MTT assay, Hochest 33258 was used to study nuclear morphology; DNA ladder and the loss of mitochondrial membrane potential were also evaluated.F-01A induces apoptosis against SPC-A-1 cells in a dose-dependent manner. The IC50 is 0.65 μmol·L(-1), and the inhibition at 5 μmol·L(-1) is 87.89%. Further, JC-1 staining indicates F-01A could induce the loss of mitochondrial membrane potential, and the DNA fragment is evident.Mechanistic analysis showed that F-01A induced apoptosis of cancer cells probably in the mitochondrial pathway. The antitumor actions of F-01A involve activation of the apoptotic pathway against SPC-A-1 cells, and it may be valuable for further drug development.

Two novel epimer pairs of acetaminophen derivatives penicilquei A-D (1-4) were isolated from Penicillium herquei JX4. Their structures were elucidated using comprehensive spectroscopic methods. The absolute configurations of penicilquei A-D (1-4) were determined by modifified Mosher's method, and comparing their experimental and calculated electronic circular dichroism (ECD) spectra. Penicilquei A-D (1-4) are the first example of acetaminophen derivatives featuring an unprecedented carbon skeleton. The inhibitory activities of all compounds against nine phytopathogenic fungi and α-glucosidase were evaluated. Penicilquei A-D (1-4) showed strong inhibitory activities against at least eight phytopathogenic fungus.

Duchenne muscular dystrophy is the most prevalent inheritable muscle disease. Transplantation of autologous stem cells with gene direction is an ideal therapeutic approach for the disease. The current study aimed to investigate the restoration of myofibers in mdx mice after mdx bone marrow-derived mesenchymal stem cell (mMSC) transplantation with human microdystrophin delivery. Possible mechanisms of action were also studied. In our research, mMSCs were successfully transduced by retrovirus carrying a functional human microdystrophin gene. Transplantation of transduced mMSCs enabled persistent dystrophin restoration in the skeletal muscle of mdx mice up to the 12th week after transplantation. Simultaneous coexpression of human microdystrophin and desmin showed that implanted mMSCs are capable of long-term survival as muscle satellite cells.

Pathogen–host interaction plays an essential role in pathogenicity. In this study, we investigated transcriptomes of one Streptococcus pneumoniae TIGR4-derived unencapsulated strain upon exposure to THP-1 human macrophage-like cells for 0.5 h, 1 h and 3 h, respectively. Expression of most genes was up-regulated and the changes of selected genes were validated by qRT-PCR. To characterize the functions of the identified genes, one locus of genes (SP1057–SP1063) was deleted in TIGR4 by insertion replacement mutagenesis. Compared to the wild-type strain, the constructed mutant exhibited lower binding and internalization activities to the THP-1 macrophages at early incubation time periods (0.5 h and/or 1 h) but not at 3 h. However, no change was observed in the intracellular survival assays. These data indicate that the SP1057–SP1063 locus is involved in the early stage of interaction with host macrophages. Further sequence and PCR analyses suggest that the SP1057–SP1063 locus was acquired by lateral transfer.

The fragmentation of 23S rRNA of 23 Haemophilus influenzae strains and eight strains belonging to other Haemophilus species was investigated. Instead of intact molecules, the 23S rRNA molecules were found to be cleaved into two to five smaller conserved fragments in most strains examined, especially in H. influenzae type b (5/6) and nontypeable strains (5/5). One or two conserved potential cleavage sites were identified by PCR analysis of the strains showing a fragmented 23S rRNA pattern. The relevant nucleotide sequences were determined and compared to H. influenzae Rd, which contains intact 23S rRNA molecules. An identical 112bp long intervening sequence (IVS) at position 542 and a conserved 121-123bp IVS sequence at position 1171 were found in two H. influenzae type b strains and one nontypeable strain. Among the strains with fragmented 23S rRNA, nearly half showed a heterogeneous cleavage pattern due to the dispersion of IVSs among different 23S rRNA operons. The localization of the conserved H. influenzae IVSs coincided well with the extensively studied IVSs among other bacteria, but differed in nucleotide sequence from any other reported IVSs. Therefore, the IVSs of Haemophilus 23S rRNA may originate from a common source that is independent of other bacteria.

The presence of a functional glpT gene in Haemophilus influenzae could be questioned, since there is only what appears to be a truncated glpT (HI0686, 143 nt in the 5'-end) available in the H. influenzae Rd genome database (Fleischmann et al. , 1995). For cloning of the glpT gene from H. influenzae type b strain Eagan, an isogenic glpT, rec-1 double mutant and a selective medium for detection of the glpT mutant strains were constructed. The recombinant plasmid carrying glpT was able to complement the isogenic glpT mutant to wild-type levels of G3P uptake and permitted growth on a selective medium with G3P as a major carbon source. The nucleotide sequences of the glpT gene were determined both directly from PCR products and from the cloned DNA insert of strain Eagan. An identical 1440 bp open reading frame with 480 deduced amino acids, highly homologous to other bacterial G3P permeases, was identified. A Northern blot analysis showed that the glpT genes in both Eagan and Rd strains were transcribed on a RNA of approximately 1.4 kb in size. Thus, it is likely that HI0686 sequence originates from a mutated glpT clone in Escherichia coli.