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Background: Cationic arginine-rich peptides (CARPs) have demonstrated neuroprotective and/or behavioural efficacy in ischemic and hemorrhagic stroke and traumatic brain injury models. Therefore, in this study we investigated the safety and neuroprotective efficacy of the CARPs poly-arginine-18 (R18; 18-mer of arginine) and its D-enantiomer R18D given in the acute bleeding phase in an intracerebral hemorrhage (ICH) model., Methods: One hundred and fifty-eight male Sprague-Dawley rats received collagenase-induced ICH. Study 1 examined various doses of R18D (30, 100, 300, or 1000 nmol/kg) or R18 (100, 300, 1000 nmol/kg) administered intravenously 30 minutes post-collagenase injection on hemorrhage volume 24 hours after ICH. Study 2 examined R18D (single intravenous dose) or R18 (single intravenous dose, plus 6 daily intraperitoneal doses) at 300 or 1000 nmol/kg commencing 30 minutes post-collagenase injection on behavioural outcomes (Montoya staircase test, and horizontal ladder test) in the chronic post-ICH period. A histological assessment of tissue loss was assessed using a Nissl stain at 28 days after ICH., Results: When administered during ongoing bleeding, neither R18 or R18D exacerbated hematoma volume or worsened functional deficits. Lesion volume assessment at 28 days post-ICH was not reduced by the peptides; however, animals treated with the lower R18D 300 nmol/kg dose, but not with the higher 1000 nmol/kg dose, demonstrated a statistically increased lesion size compared to saline treated animals., Conclusion: Overall, both R18 and R18D appeared to be safe when administered during a period of ongoing bleeding following ICH. Neither peptide appears to have any statistically significant effect in reducing lesion volume or improving functional recovery after ICH. Additional studies are required to further assess dose efficacy and safety in pre-clinical ICH studies., Competing Interests: L. Liddle, F.Colbourne, R.Reinders, S. South, & D. Blacker, have no conflict of interest to disclose. B.P. Meloni and N.W. Knuckey are named inventors of several patent applications (Provisional Patents: 2013904197; 30/ 10/2013 and 2014902319; 17/6/2014 and PCT/ AU2014/050326;520 30/10/2104) regarding the use of arginine-rich peptides as neuroprotective agents. This does not alter our adherence to PLOS ONE policies on sharing data and materials.

The effects of proline and caffeic acid on the survival of Shiga toxin-producing Escherichia coli (STEC) O157:H7 strain ATCC 43895 in a model apple juice medium were studied. It is hypothesized that the inhibitory effect of caffeic acid may explain why almost all outbreaks of STEC O157:H7 infections linked to apple juice or cider have occurred in October or November.

In this study irradiation of intact cells with 244-nm ultraviolet light was used to cross-link hnRNA to proteins that are closely associated with it. In this way proteins interacting specifically with hnRNA could be identified excluding the possibility of non-specific binding of proteins to the RNA during cell fractionation. In uninfected HeLa cells two polypeptides of 41500 and 43000 molecular weight can be cross-linked very efficiently to hnRNA. Other proteins, with molecular weights of 36000 and 37000, were covalently linked less effectively. Irradiation of adenovirus-infected cells results in the cross-linking of the same polypeptides to hnRNA. It was found, however, that hnRNA from adenovirus-infected cells contains both viral and host transcripts. Both classes of transcripts are quantitatively associated with the nuclear matrix and can be cross-linked by irradiation with equal efficiency. To determine whether both adenoviral and cellular transcripts are associated with the same proteins, the cross-linked adenoviral hnRNA-protein complexes were isolated by preparative hybridization to adenoviral DNA immobilized on Sepharose. The results show that the purified cross-linked adenoviral hnRNA-protein complexes also contain the host 41500-Mr and 43000-Mr proteins as major components. This suggests that in the infected cell adenoviral-specific hnRNA is associated with host proteins and that the structural organization of viral hnRNA-protein complexes in infected cells probably is similar to the organization of host hnRNA in uninfected cells.

Ehrlich ascites tumor cells were irradiated with ultraviolet light to cross-link intracellular RNAs to their tightly bound proteins. The efficiency of such cross-linking in vivo was measured by two independent methods, namely by phenol/chloroform extraction and by isopycnic centrifugation. After short irradiation times more than 70% of the ribosomal RNAs and more than 80% of the mRNA were found to be cross-linked to protein. The size of the cross-linked RNAs was essentially unchanged, indicating that the irradiation does not lead to extensive fragmentation of the RNA. Covalent poly(A)-containing mRNA-protein complexes were isolated by oligo(dT)-cellulose chromatography in the presence of sodium dodecylsulphate. The complexed proteins were freed from RNA by extensive nuclease degradation and analysed by polyacrylamide gel electrophoresis. The results show that some specific proteins are associated with poly(A)-containing RNA in vivo.