Graphyne sheet exhibits promising potential for nanoscale desalination to achieve both high water permeability and salt rejection rate. Extensive molecular dynamics simulations on pore-size effects suggest that γ-graphyne-4, with 4 acetylene bonds between two adjacent phenyl rings, has the best performance with 100% salt rejection and an unprecedented water permeability, to our knowledge, of ~13 L/cm(2)/day/MPa, 3 orders of magnitude higher than prevailing commercial membranes based on reverse osmosis, and ~10 times higher than the state-of-the-art nanoporous graphene. Strikingly, water permeability across graphyne exhibits unexpected nonlinear dependence on the pore size. This counter-intuitive behavior is attributed to the quantized nature of water flow at the nanoscale, which has wide implications in controlling nanoscale water transport and designing highly effective membranes.

An ethyl acetate (EtOAc) extract isolated from the marine bacterium, Rheinheimera aquimaris QSI02, was found to exhibit anti-quorum sensing (anti-QS) activity. A subsequent bioassay-guided isolation protocol led to the detection of an active diketopiperazine factor, cyclo(Trp-Ser). Biosensor assay data showed that the minimum inhibitory concentration (MIC) of cyclo(Trp-Ser) ranged from 3.2 mg/ml to 6.4 mg/m for several microorganisms, including Escherichia coli, Chromobacterium violaceum CV026, Pseudomonas aeruginosa PA01, Staphylococcus aureus, and Candida albicans. Additionally, sub-MICs of cyclo(Trp-Ser) decreased the QS-regulated violacein production in C. violaceum CV026 by 67%. Furthermore, cyclo(Trp-Ser) can decrease QS-regulated pyocyanin production, elastase activity and biofilm formation in P. aeruginosa PA01 by 65%, 40% and 59.9%, respectively. Molecular docking results revealed that cyclo(Trp-Ser) binds to CviR receptor more rigidly than C6HSL with lower docking energy -8.68 kcal/mol, while with higher binding energy of -8.40 kcal/mol than 3-oxo-C12HSL in LasR receptor. Molecular dynamics simulation suggested that cyclo(Trp-Ser) is more easy to bind to CviR receptor than natural signaling molecule, but opposite in LasR receptor. These results suggest that cyclo(Trp-Ser) can be used as a potential inhibitor to control QS systems of C. violaceum and P. aeruginosa and provide increased the understanding of molecular mechanism that influences QS-regulated behaviors.

In this study we examined the anti-leukemia activity of a small molecule inhibitor of Hsp70 proteins, apoptozole (Az), and hybrids in which it is linked to an inhibitor of either Hsp90 (geldanamycin) or Abl kinase (imatinib). The results of NMR studies revealed that Az associates with an ATPase domain of Hsc70 and thus blocks ATP binding to the protein. Observations made in the cell study indicated that Az treatment promotes leukemia cell death by activating caspase-dependent apoptosis without affecting the caspase-independent apoptotic pathway. Importantly, the hybrids composed of Az and geldanamycin, which have high inhibitory activities towards both Hsp70 and Hsp90, exhibit enhanced anti-leukemia activity relative to the individual inhibitors. However, the Az and imatinib hybrids have weak inhibitory activities towards Hsp70 and Abl, and display lower cytotoxicity against leukemia cells compared to those of the individual constituents. The results of a mechanistic study showed that the active hybrid molecules promote leukemia cell death through a caspase-dependent apoptotic pathway. Taken together, the findings suggest that Hsp70 inhibitors as well as their hybrids can serve as potential anti-leukemia agents.

Triple-negative breast cancer (TNBC) is a high-risk subtype of breast cancer with high capacity for metastasis and lacking of therapeutic targets. Our previous studies indicated that cystathionine γ-lyase (CSE) may be a new target related to the recurrence or metastasis of TNBC. Downregulation of CSE could inhibit the growth and metastasis of TNBC. The purpose of this study was to investigate the activity of the novel CSE inhibitor I194496 against TNBC in vivo and in vitro. The anticancer activity of I194496 in vitro were detected by MTS, EdU, and transwell assays. Methylene blue assay was used to determine the H2S level. Western blot was performed to analyze the expression of related pathway proteins. Xenograft tumors in nude mice were used to analyze the anticancer activity of I194496 in vivo. I194496 exerted potent inhibitory effects than L-propargylglycine (PAG, an existing CSE inhibitor) on human TNBC cells and possessed lower toxicity in normal breast epithelial Hs578Bst cells. I194496 reduced the activity and expression of CSE protein and the release of H2S in human TNBC cells. Meanwhile, the protein levels of PI3K, Akt, phospho (p)-Akt, Ras, Raf, p-ERK, p-Anxa2, STAT3, p-STAT3, VEGF, FAK, and Paxillin were decreased in human TNBC cells administrated with I194496. Furthermore, I194496 showed more stronger inhibitory effects on human TNBC xenograft tumors in nude mice. I194496 could inhibit the growth of human TNBC cells via the dual targeting PI3K/Akt and Ras/Raf/ERK pathway and suppress the metastasis of human TNBC cells via down-regulating Anxa2/STAT3 and VEGF/FAK/Paxillin signaling pathways. CSE inhibitor I194496 might become a novel and potential agent in the treatment of TNBC.