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In this paper, we mainly prove a congruence conjecture of M. Apagodu [3] and a supercongruence conjecture of Z.-W. Sun [25] .

Ethnopharmacological relevance In traditional Chinese medicine, the aerial parts of Aeschynomene indica L. (AIL) have been used for wound healing, and to treat urinary tract infection, hepatitis, enteritis, dysentery, nyctalopia, conjunctivitis, urticaria, and furuncle. However, no scientific investigation has been conducted on its wound healing potential. Aim of the study To investigate the effects of AIL extract on wound healing, isolate the active constituent and reveal the possible mechanism of enhancing wound healing. Materials and methods The circular excision wound healing model was used to evaluate in vivo wound-healing activity. Hematoxylin and eosin staining was applied to assess inflammatory cells infiltration, angiogenesis, fibroblast proliferation, collagen synthesis, collagen remodeling, and skin appendages generation. Sirius red-picric acid staining was employed for quantitative analysis of the ratio of collagen I/III. Immunohistochemical staining for CD68, CCR7 (CD197), CD163, TGF-β1 and α-SMA was performed to determine macrophages phenotypes transition (M1-to-M2) and prove the scar-improving effect of AIL on wound healing. Results We successfully isolated the active constituent (Sub-Fr0.2) for wound healing from AIL extract, circular excision wound healing experiment and hematoxylin & eosin staining showed Sub-Fr0.2 has a significant promoting effect on wound healing. Results of sirius red-picric acid staining demonstrated a reduced ratio of collagen I/III in the Sub-Fr0.2 group as compared with the vehicle group. Immunohistochemical staining for CD68, CCR7 (CD197), and CD163 in the Sub-Fr0.2 group exhibited an elevated speed of macrophages transiting from M1 phenotype to M2 phenotype, when compared with the vehicle group. Besides, the expression of TGF-β1 and α-SMA were inhibited on wounds treated with the ointment containing Sub-Fr0.2. Conclusion Leaves of AIL and its active constituent (Sub-Fr0.2) effectively promoted wound healing and reduced scar formation, this efficacy might be exerted by accelerating macrophages phenotypes transition and inhibiting TGF-β1 and α-SMA expression.

Poor wound healing is a major and global threat to public health. Efforts have been made to better understand the underlying mechanisms and develop effective remedies, though the advancements that have been made are still limited. As there are no effective and generally applicable therapies available for skin injuries and fibrosis, it is urgent to develop new drugs and therapies that facilitate wound healing and effectively improve scars. In this study, GC-MS analysis was performed to identify the chemical composition of rosehip oil. The excisional wound healing model and the carrageenan-induced paw edema method were respectively applied to evaluate the wound healing activity and anti-inflammatory activity of rosehip oil. Hematoxylin and eosin staining was used to assess the pathological changes of sections, and Sirius-red staining was performed to analyze the ratio of collagen I/III in wound tissues. Immunohistological staining for CD68, CCR7 (CD197), CD163, TGF-β1, and α-SMA was applied to determine the macrophage phenotypes transition (M1-to-M2) and demonstrate the scar-improving efficacy of rosehip oil on wound healing. Results showed that rosehip oil significantly promoted wound healing and effectively improved scars. This efficacy might be exerted by accelerating the macrophage phenotypes transition and inhibiting the process of epithelial-mesenchymal transition.

SARS‐CoV spike (S) protein‐mediated cell fusion is important for the viral entry mechanism and identification of SARS‐CoV entry inhibitors. In order to avoid the high risks involved in handling SARS‐CoV and to facilitate the study of viral fusion mechanism, we established the cell lines: SR‐COS7 cells that stably express both SARS‐CoV S protein and red fluorescence protein, R‐COS7 cells that stably express red fluorescence protein, and AG‐COS7 cells that stably express both ACE2 and green fluorescence protein, respectively. When SR‐COS7 cells or R‐COS7 cells were cocultured with AG‐COS7 cells, syncytia with yellow fluorescence were conveniently observed after 12 h in SR‐COS7 cells plus AG‐COS7 cells, but not in R‐COS7 cells plus AG‐COS7 cells. The cell‐to‐cell fusion efficiency was simply determined for quantitative analysis based on the number of syncytium detected by flow cytometry. Such new cell‐to‐cell fusion model was further assessed by the potent HR2 peptide inhibitor, which led to the obvious decrease of the cell‐to‐cell fusion efficiency. The successful fusion and inhibition of cell‐based binding assay shows that it can be well used for the study of SARS‐CoV entry and inhibition. iubmb Life, 58: 480 ‐ 486, 2006

Based on the reported cDNA sequences of BmKalphaTxs , the genes encoding toxin BmKalphaTx11 and BmKalphaTx15 were amplified by PCR from the Chinese scorpion Buthus martensii Karsch genomic DNA employing synthetic oligonucleotides. Sequences analysis of nucleotide showed that an intron about 500 bp length interrupts signal peptide coding regions of BmKalphaTx11 and BmKalphaTx15. Using cDNA sequence of BmKalphaTx11 as probe, southern hybridization of BmK genome total DNA was performed. The result indicates that BmKalphaTx11 is multicopy genes or belongs to multiple gene family with high homology genes. The similarity of BmKalpha-toxin gene sequences and southern hybridization revealed the evolution trace of BmKalpha-toxins: BmKalpha-toxin genes evolve from a common progenitor, and the genes diversity is associated with a process of locus duplication and gene divergence.

Background The human ether-a-go-go-related gene potassium channel (hERG) has an unusual long turret, whose role in recognizing scorpion toxins remains controversial. Here, BmKKx2, the first specific blocker of hERG channel derived from scorpion Mesobuthus martensii, was identified and the turret role of hERG channel was re-investigated using BmKKx2 as a molecular probe. Results BmKKx2 was found to block hERG channel with an IC50 of 6.7 ± 1.7 nM and share similar functional surface with the known hERG channel inhibitor BeKm-1. The alanine-scanning mutagenesis data indicate that different residue substitutions on hERG channel by alanine decreased the affinities of toxin BmKKx2 by about 10-fold compared with that of wild-type hERG channel, which reveals that channel turrets play a secondary role in toxin binding. Different from channel turret, the pore region of hERG channel was found to exert the conserved and essential function for toxin binding because the mutant hERG-S631A channel remarkably decreased toxin BmKKx2 affinity by about 104-fold. Conclusions Our results not only revealed that channel turrets of hERG channel formed an open conformation in scorpion toxin binding, but also enriched the diversity of structure-function relationships among the different potassium channel turrets.

Based on the full-length cDNA of BmalphaTX14 from Chinese scorpion Buthus martensii Karsch (BmK), gene of the mature peptide of BmalphaTX14 was cloned into the yeast expression vector pPIC9K. After transforming, screening and inducing, tricine-SDS-PAGE and Western blot proved that rBmalphaTX14 protein was expressed in the medium for up to 84 hours, getting nearly 120 mg/L. Recombinant BmalphaTX14 was purified rapidly and efficiently through Ni-NTA-agarose, polyethylene glycol precipitation and gel filtration chromatography. The purified rBmalphaTX14 proved to have the anti-insect activity by toxicity assay. Meanwhile, genomic gene of BmalphaTX14 was cloned and sequenced by PCR method, sequence analysis of this gene showed that BmalphaTX14 had an intron of 408 base pairs located at the signal peptide encoding region, which was similar with the characteristic of other alpha-type sodium ion-channel toxin. Considering both the genomic organization and the peptide function, BmaTX14 proved to be a membership belonging to alpha-type sodium ion-channel toxin.

Scorpion venoms contain different types of low molecular mass toxic peptides acting on ion channels. Many cDNAs and genomic genes encoding these toxins have been isolated and sequenced while the mechanisms of expression and regulation of scorpion toxins is not well studied yet. BmTXK beta, one of the four putative long-chain potassium channel toxins, is isolated from the cDNA library of the venom gland of Chinese scorpion BmK (Buthus martensii Karsch). It has an 886 bp intron located in the mature peptide while other scorpion toxins' introns are located in the signal peptide. The special genomic organization of BmTXK beta makes it a good object to study the mechanism of expression and regulation of scorpion toxins. With primers designed according to the already known sequence of BmTXK beta, its 5' and 3' flanking regions are cloned by the Vecttorette II Staorette Pack method and sequenced. Analysis of the sequence shows that another intron longer than 997 bp is located in the signal peptide region of BmTXK beta, which makes BmTXK beta different from all the other scorpion toxins that have no intron or only one intron in the signal peptide. The special genomic organization of BmTXK beta indicates that BmTXK beta is a new membership of long-chain potassium channel toxin.