Humic substances (HSs) have considerable effects on soil fertility and crop productivity owing to their unique physiochemical and biochemical properties, and play a vital role in establishing biotic and abiotic interactions within the plant rhizosphere. A comprehensive understanding of the mode of action and tissue distribution of HS is, however, required, as this knowledge could be useful for devising advanced rhizospheric management practices. These substances trigger various molecular processes in plant cells, and can strengthen the plant’s tolerance to various kinds of abiotic stresses. HS manifest their effects in cells through genetic, post-transcriptional, and post-translational modifications of signaling entities that trigger different molecular, biochemical, and physiological processes. Understanding of such fundamental mechanisms will provide a better perspective for defining the cues and signaling crosstalk of HS that mediate various metabolic and hormonal networks operating in plant systems. Various regulatory activities and distribution strategies of HS have been discussed in this review.

A series of new benzothiazole derivatives 6a-h have been synthesized, in five steps, from substituted phenols via the 1,3,4-oxadiazole-2-thiones 5a-h. The in vitro antitumor activity of the compounds obtained was investigated and the benzothiazol derivatives 6d and 6e showed strong effects on leukaemia cell lines CCRF-CEM (CC50=12+/-2 micromol L(-1), 8+/-1 micromol L(-1), respectively). These compounds are leading candidates for further development. The title compounds were tested against representatives of several virus families containing single stranded RNA genomes, either positive-sense (ssRNA+), or negativesense (RNA-), and against double-stranded RNA genomes (dsRNA), as well as some Flaviviridae viruses

Retinal organoids (ROs) derived from human induced pluripotent stem cells (hiPSCs) provide potential opportunities for studying human retinal development and disorders; however, to what extent ROs recapitulate the epigenetic features of human retinal development is unknown. In this study, we systematically profiled chromatin accessibility and transcriptional dynamics over long-term human retinal and RO development. Our results showed that ROs recapitulated the human retinogenesis to a great extent, but divergent chromatin features were also discovered. We further reconstructed the transcriptional regulatory network governing human and RO retinogenesis in vivo. Notably, NFIB and THRA were identified as regulators in human retinal development. The chromatin modifications between developing human and mouse retina were also cross-analyzed. Notably, we revealed an enriched bivalent modification of H3K4me3 and H3K27me3 in human but not in murine retinogenesis, suggesting a more dedicated epigenetic regulation on human genome.

5-substituted 4-(4-chlorophenyl)- 4H-1,2,4-triazol-3-thiones 3 and 2-substituted 5-(4-chlorophenylamino)-1,3,4-thiadiazoles 4 were prepared from the intermediate thiosemicarbazides 2 under basic and acidic conditions, respectively. The thiosemicarbazides, in turn, were prepared by the reaction of hydrazides 1 with 4-chlorophenylisothiocyanate in MeOH. Some of the new synthesized compounds were assayed against HIV-1 and HIV-2 in MT-4 cells. All the compounds were inactive except 3f, which showed an EC 50 value of 23.9 µg/mL and 9.9 µg/mL against HIV-1 and HIV-2 with a therapeutic index of 3 and 7, respectively. It means that compound 3f was cytotoxic to MT-4 cells at CC 50 of 72.7 µg/mL in both strains. C 2007 Wiley Periodicals, Inc.

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Systems biology and omics has provided a comprehensive understanding about the dynamics of the genome, metabolome, transcriptome, and proteome under stress. In wheat, abiotic stresses trigger specific networks of pathways involved in redox and ionic homeostasis as well as osmotic balance. These networks are considerably more complicated than those in model plants, and therefore, counter models are proposed by unifying the approaches of omics and stress systems biology. Furthermore, crosstalk among these pathways is monitored by the regulation and streaming of transcripts and genes. In this review, we discuss systems biology and omics as a promising tool to study responses to oxidative, salinity, and drought stress in wheat.

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Chiral 3-substituted-4-amino-5-thioxo-1H,4H-1,2,4-triazoles (5a-i) were synthesized. The target molecules were prepared by cyclization of the corresponding dithiocarbazinic acids, obtained from hydrazides, in the presence of hydrazine hydrate. The chiral hydrazides were in turn synthesized form L-amino acids. The structures of all the compounds were confirmed by modern spectroscopic techniques and purity ascertained by elemental analysis. The synthesized compounds 5a-i were evaluated for urease inhibition and found to exhibit varying degrees of urease inhibition activity showing IC(50) values ranging from 22.0 +/- 0.5 to 43.8 +/- 0.3 microM. Compound 5b was found to be the most active, exhibiting IC(50) = 22.0 +/- 0.5 microM comparable to the standard, thiourea (IC(50) = 21.0 +/- 0.1 microM). Triazoles 5a-i were also screened for their antimicrobial properties and promising antibacterial activities were observed against five pathogenic bacteria. However, all the compounds were devoid of any antifungal activity.