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A new Pb(II) complex, [Pb(8-OQ)(4-NB)], where 8-OQ = 8-hydroxyquinolinate, 4-NB = 4-nitrobenzoate, has been synthesized and characterized by elemental analysis, IR spectroscopy, and X-ray single-crystal diffraction. The single crystal X-ray analysis reveals that the complex possesses a tetranuclear Pb4O4 cubane structure. The Pb(II) atom is coordinated by three triply bridging phenolic hydroxyl O atoms of 8-OQ ligands, then the tetranuclear Pb system is formed resulting in a tetrahedral cage. The interaction of complex with HS-DNA in Tris buffer was studied by UV−vis absorption spectrum and fluorescence ethidium bromide displacement experiment with an intrinsic binding constant of 1.52×104 M-1 and a linear Stern–Volmer quenching constant of 6.77×103 M-1. Anticancer activity against MCF-7, HepG-2 and A549 cell lines of complex was also determined by the MTT-based assay. The results showed the complex can inhibit proliferation of these three kinds of tumor cells and is less cytotoxic than cisplatin.

A new one-dimensional (1D) coordination polymer, [Pb2(psa)(phen)2(NO3)2]n, has been synthesized by the method of hydrothermal reaction and characterized by elemental analysis, FT-IR and X-ray single-crystal diffraction (where H2psa is phenylsuccinic acid and phen is 1,10-phenanthroline). The single-crystal X-ray analysis showed that the complex has a dinuclear core stabilized by bridging phenylsuccinic acids and nitrate anions. The coordination number of the two Pb(II) atoms are 7 and 6, with the stereochemically active lone pair, resulting in the hemidirected geometry for the complex. The complex contain a 1D chain, which is further extended into two-dimensional supramolecular architecture through hydrogen bonds, C-H···π, and π···π interactions.

Gastrointestinal diseases are highly prevalent, and their burden significantly impacts the quality of life of affected individuals. Inflammatory and immune-mediated intestinal diseases usually have a chronic course without adequate therapeutic modalities. Although much has been reported to comprehend these diseases, many remain resistant and refractory to conventional treatment approaches. Therefore, recent approaches to cellular therapy using stem cells, like hematopoietic stem cells and mesenchymal stem cells, and other cellular immunosuppressive modalities, like T-regulatory cells, were introduced and investigated in treating gastrointestinal diseases. We aimed to conduct a literature review to discuss the applications and challenges of cellular therapeutics in gastrointestinal diseases. Evidence from published clinical trials supports the safety and efficacy of cellular treatment in different immune-mediated and inflammatory gastrointestinal diseases. They can offer a longer duration of remission, being able to adjust the dysregulated immune system. However, there are various challenges to be considered by future trials, including the limitations of current clinical trials, challenges in retrieval and application of these therapeutics, and their mutagenesis potential.

Objective: To investigate the effect of short hairpin RNA (shRNA) targeting hypoxia-inducible factor-1 alpha (HIF-1 alpha) on the human breast carcinoma MCF-7 cell line., Methods: The hypoxia environment was achieved by treating cells with cobalt chloride. The shRNA eukaryotic expression vector targeting HIF-1 alpha was constructed, and transfected into MCF-7 cells through lipofectamine 2000. Semi-quantitative reverse transcription-polymerase chain reaction (RT-PCR) was used to study the expression of vascular endothelial growth factor (VEGF). The mRNA and protein level of HIF-1 alpha were detected by real-time PCR and Western blot. Sub-G1 apoptotic population analysis, Annexin V/PI binding assay, and DNA ladder analysis were applied to investigate the cell apoptosis. The cell cycle was detected by flow cytometry., Results: The mRNA and protein level of HIF-1 alpha increased after exposure of MCF-7 cells to hypoxia (P < 0.01). However, apoptosis was lower in hypoxia compared with normoxia (P < 0.05). The HIF-1 level of MCF-7 transfected with HIF-1 alpha shRNA decreased approximately 91.63% (P < 0.01). When the cells were treated with or without apoptosis inducer Ara-C, the apoptosis of MCF-7 cells transfected with HIF-1 alpha shRNA increased by 1.75 times (P < 0.01) and 61. 31 times (P < 0.01), respectively. The expression of VEGF in MCF-7 cells transfected with HIF-1 alpha shRNA decreased 66.8% compared with untransfected cells (P < 0.05). Cell cycle progression was inhibited when the MCF-7 cells were transfected with HIF-1 alpha shRNA., Conclusions: HIF-1 alpha plays an anti-apoptotic role in human breast carcinoma MCF-7 cell line. The shRNA we designed targeting HIF-1 alpha in MCF-7 can promote cell apoptosis, inhibit the expression of VEGF, and delay cell cycle progression.

Background and Objectives: The aim of this study was to construct a eukaryotic expression vector containing human hemangiopoietin (hHAPO) gene and express it in mouse bone marrow stromal cell line HESS-5, then support hematopoiesis in vitro with gene-modified HESS-5 (hHAPO-HESS-5)., Design and Methods: The polymerase chain reaction (PCR) products of HAPO were digested with BamHI and BgII. Then the HAPO gene segment obtained was again cloned into pIRES2-EGFP to construct recombinant eukaryotic expression vector HAPO-pIRES2-EGFP. The recombinant vector was identified by enzyme digestion analysis, PCR, and sequencing. HESS-5 cells were transformed by recombinant vector and positive clones were selected with G418. The expression of HAPO gene in the transformed cells was detected by studying EGFP expression, reverse transcription (RT)-PCR, and Western-blotting analysis. Support of human hematopoiesis by hHAPO-HESS-5 cells was evaluated in co-culture experiments with human CD34+ cells., Results: Enzyme digestion analysis and sequencing showed that the target gene had been cloned into the recombinant vector. The expression of HAPO gene in the transformed stromal cells was demonstrated by fluoro-microscopy and RT-PCR analysis. HAPO protein was also detected in the supernatant of hHAPO-HESS-5 by Western blot analysis. As expected, stably transfected hHAPO-HESS-5 cells significantly increased in both relative and absolute numbers of CD34+ cells after 14 days of culture. The PKH26 study demonstrated that cell division was faster in CD34+ cells co-cultured with hHAPO-HESS-5 cells than in cells cocultured with vector-HESS-5 cells. The hHAPO-HESS-5 cells also supported human hematopoiesis in vitro more efficiently than did control vector-HESS-5 cells., Interpretation and Conclusions: A recombinant eukaryotic expression vector has been constructed and expressed successfully in transformed cells. The hHAPO-HESS-5 cells support rapid generation of primitive progenitor cells and maintain reconstituting ability of hematopoietic stem cells in vitro. Therefore, it would be possible to use stromal cells expressing HAPO gene as seed cells in the bone marrow transplantation.