Relationship between Chemical Structure and Selectivity in Herbicidal Activity of trans-β-(2,4-Dichlorophenoxy)-acrylates against Rice Plant and Barnyard-grass

Twenty one esters of trans β-(2,4-dichlorophenoxy)acrylic acid were prepared and their inhibitory activity against shoot elongation in the rice plant and barnyard-grass was measured. The relationship between herbicidal activity and chemical structure was analysed using the Hansch approach. The selectivity (activity against barnyard-grass/activity against the rice plant) was mainly due to the lipophilic property of the esters between the two plant species.     

Enzymatic synthesis of unique sialyloligosaccharides using marine bacterial α-(2→3)- and α-(2→6)-sialyltransferases

We investigated the acceptor substrate specificities of marine bacterial α-(2→3)-sialyltransferase cloned from Photobacterium sp. JT-ISH-224 and α-(2→6)-sialyltransferase cloned from Photobacterium damselae JT0160 using several saccharides as acceptor substrates. After purifying the enzymatic reaction products, we confirmed their structure by NMR spectroscopy. The α-(2→3)-sialyltransferase transferred N-acetylneuraminic acid (Neu5Ac) from cytidine 5′-monophospho-N-acetylneuraminic acid (CMP-Neu5Ac) to the β-anomeric hydroxyl groups of mannose (Man) and α-Manp-(1→6)-Manp, and α-(2→6)-sialyltransferase transferred N-acetylneuraminic acid to the 6-OH groups of the non-reducing end galactose residues in β-Galp-(1→3)-GlcpNAc and β-Galp-(1→6)-GlcpNAc.     

Analysis of the internal motion of free and ligand-bound human lysozyme by use of 15N NMR relaxation measurement: a comparison with those of hen lysozyme

Human lysozyme has a structure similar to that of hen lysozyme and differs in amino acid sequence by 51 out of 129 residues with one insertion at the position between 47 and 48 in hen lysozyme. The backbone dynamics of free or (NAG)3-bound human lysozyme has been determined by measurements of 15N nuclear relaxation. The relaxation data were analyzed using the Lipari-Szabo formalism and were compared with those of hen lysozyme, which was already reported (Mine S et al.. 1999, J Mol Biol 286:1547-1565). In this paper, it was found that the backbone dynamics of free human and hen lysozymes showed very similar behavior except for some residues, indicating that the difference in amino acid sequence did not affect the behavior of entire backbone dynamics, but the folded pattern was the major determinant of the internal motion of lysozymes. On the other hand, it was also found that the number of residues in (NAG)3-bound human and hen lysozymes showed an increase or decrease in the order parameters at or near active sites on the binding of (NAG)3, indicating the increase in picosecond to nanosecond. These results suggested that the immobilization of residues upon binding (NAG)3 resulted in an entropy penalty and that this penalty was compensated by mobilizing other residues. However, compared with the internal motions between both ligand-bound human and hen lysozymes, differences in dynamic behavior between them were found at substrate binding sites, reflecting a subtle difference in the substrate-binding mode or efficiency of activity between them.     

Serum heat shock protein 47 levels are elevated in acute exacerbation of idiopathic pulmonary fibrosis

Little is known about the pathophysiology of acute exacerbation (AE) of idiopathic pulmonary fibrosis (IPF). Heat shock protein 47 (HSP47), a collagen-specific molecular chaperone, is essential for biosynthesis and secretion of collagen molecules. Previous studies in experimental animal fibrosis models have shown that downregulation of HSP47 expression reduces collagen production and diminishes fibrosis progression. In this study, serum HSP47 levels were evaluated to elucidate pathogenic differences involving HSP47 between AE-IPF and stable (S)-IPF. Subjects comprised 20 AE-IPF and 33 S-IPF patients. Serum levels of HSP47, Krebs von den Lungen-6 (KL-6), surfactant protein (SP)-A, SP-D, and lactate dehydrogenase (LDH) were measured. Immunohistochemical analysis of lung HSP47 expression was determined in biopsy and autopsy tissues diagnosed as diffuse alveolar damage (DAD) and usual interstitial pneumonia (UIP). Serum levels of HSP47 were significantly higher in AE-IPF than in S-IPF patients, whereas serum levels of KL-6, SP-A, and SP-D did not differ significantly. Receiver operating characteristic curves revealed that HSP47 was superior for discriminating AE-IPF and S-IPF. The cutoff for HSP47 resulting in the highest diagnostic accuracy was 559.4 pg/mL; sensitivity, specificity, and diagnostic accuracy were 100.0 %, 93.9 %, and 96.2 %, respectively. Immunohistochemical analysis revealed that pulmonary HSP47 expression was greater in DAD than UIP tissues. Serum HSP47 was significantly higher in AE-IPF than in S-IPF patients, suggesting that underlying fibrogenic mechanisms involving HSP47 differ in the two conditions.     

Cleavage of human big endothelin-1 by Candida albicans aspartic proteinase

Abstract A Candida albicans aspartic proteinase (CAP), one of the secretory proteinases of Candida albicans , is thought to be a possible virulence factor in Candida albicans infection. Whereas endothelin-1 is found as an endothelium-derived strong vasoconstrictive peptide, it is known to have a role in the maintenance of vascular homeostasis and tissue survival. Endothelin-1 is generated from a precursor form of endothelin-1, the so-called big endothelin-1. It has recently been reported that cathepsin D, E and pepsin, which are aspartic proteinases, convert big endothelin-1 to endothelin-1. In this study, the relationship between CAP and big endothelin-1 was studied. High performance liquid chromatography analysis revealed that big endothelin-1 was cleaved into several amino acid sites by CAP, but endothelin-1 was not converted from big endothelin-1. CAP cleaved big endothelin-1 at different sites when compared with that of other known aspartic proteinases, and it suppressed endothelin-1 production through the degradation of big endothelin-1. CAP may break homeostatic mechanism of endothelin-1 in Candida albicans infectious lesion.     

Membranous glomerulonephritis development with Th2-type immune deviations in MRL/lpr mice deficient for IL-27 receptor (WSX-1)

MRL/lpr mice develop spontaneous glomerulonephritis that is essentially identical with diffuse proliferative glomerulonephritis (World Health Organization class IV) in human lupus nephritis. Lupus nephritis is one of the most serious complications of systemic lupus erythematosus. Diffuse proliferative glomerulonephritis is associated with autoimmune responses dominated by Th1 cells producing high levels of IFN-gamma. The initial mounting of Th1 responses depends on the function of the WSX-1 gene, which encodes a subunit of the IL-27R with homology to IL-12R. In mice deficient for the WSX-1 gene, proper Th1 differentiation was impaired and abnormal Th2 skewing was observed during infection with some intracellular pathogens. Disruption of the WSX-1 gene dramatically changed the pathophysiology of glomerulonephritis developing in MRL/lpr mice. WSX-1-/- MRL/lpr mice developed disease resembling human membranous glomerulonephritis (World Health Organization class V) with a predominance of IgG1 in glomerular deposits, accompanied by increased IgG1 and IgE in the sera. T cells in WSX-1-/- MRL/lpr mice displayed significantly reduced IFN-gamma production along with elevated IL-4 expression. Loss of WSX-1 thus favors Th2-type autoimmune responses, suggesting that the Th1/Th2 balance may be a pivotal determinant of human lupus nephritis development.     

Interspecific root interactions and rhizosphere effects on salt ions and nutrient uptake between mixed grown peanut/maize and peanut/barley in original saline-sodic-boron toxic soil

Two glasshouse studies were conducted to investigate the effect of interspecific complementary and competitive root interactions and rhizosphere effects on the concentration and uptake of Na, Cl and B, and N, P, K, Ca, Mg, Fe, Zn and Mn nutrition of mixed cropped peanut with maize (Experiment I), and barley (Experiment II) grown in nutrient-poor saline-sodic and B toxic soil. Mixed cropped plants were grown in either higher density or lower density. The results of the experiment revealed that dry shoot weight decreased in peanut but increased in maize and barley with associated plant species compared to their monoculture. Shoot Na and Cl concentrations of peanut decreased significantly in both experiments, regardless of higher or lower density. The concentrations of Na also decreased in the shoots of mixed cropped maize and barley, but Cl concentrations increased slightly. The concentration of B significantly decreased in mixed cropping in all plant species regardless of higher or lower density. Rhizosphere chemistry was strongly and differentially modified by the roots of peanut, maize and barley, and mixed growing. There were significant correlations between the root-secreted acid phosphatases (S-APase), acid phosphatase in rhizosphere (RS-APase) and rhizosphere P concentration (RS-P) in the both experiments. The Fe-solubilizing activity (Fe-SA) and ferric reducing (FR) capacity of the roots were generally higher in mixed culture relative to their monoculture, which improved Fe, Zn and Mn nutrition of peanut. Further, there were also significant correlations among FR, Fe-SA and RS-Fe concentrations. Peanut facilitated P nutrition of maize and barley, while maize and barley improved K, Fe, Zn and Mn nutrition of peanut grown in nutrient-poor saline-sodic and B toxic soil.     

Colorectal cancer invasiveness in vitro: Predominant contribution of neonatal Nav1.5 under normoxia and hypoxia

Functional expression of voltage-gated Na⁺ channels (VGSCs) occurs in human carcinomas and promotes invasiveness in vitro and metastasis in vivo. Both neonatal and adult forms of Nav1.5 (nNav1.5 and aNav1.5, respectively) have been reported to be expressed at messenger RNA (mRNA) level in colorectal cancer (CRCa) cells. Here, three CRCa cell lines (HT29, HCT116 and SW620) were studied and found to express nNav1.5 mRNA and protein. In SW620 cells, adopted as a model, effects of gene silencing (by several small interfering RNAs [siRNAs]) selectively targeting nNav1.5 or aNav1.5 were determined on (a) channel activity and (b) invasiveness in vitro. Silencing nNav1.5 made the currents more “adult-like” and suppressed invasion by up to 73%. Importantly, subsequent application of the highly specific, general VGSC blocker, tetrodotoxin (TTX), had no further effect. Conversely, silencing aNav1.5 made the currents more “neonatal-like” but suppressed invasion by only 17% and TTX still induced a significant effect. Hypoxia increased invasiveness and this was also blocked completely by siRNA targeting nNav1.5. The effect of hypoxia was suppressed dose dependently by ranolazine, but its effect was lost in cells pretreated with nNav1.5-siRNA. We conclude that (a) functional nNav1.5 expression is common to human CRCa cells, (b) hypoxia increases the invasiveness of SW620 cells, (c) the VGSC-dependent invasiveness is driven predominantly by nNav1.5 under both normoxic and hypoxic conditions and (d) the hypoxia-induced increase in invasiveness is likely to be mediated by the persistent current component of nNav1.5.     

Effectiveness of a WHO self‐help psychological intervention for preventing mental disorders among Syrian refugees in Turkey: a randomized controlled trial

Refugees are at high risk of developing mental disorders. There is no evidence from randomized controlled trials (RCTs) that psychological interventions can prevent the onset of mental disorders in this group. We assessed the effectiveness of a self‐help psychological intervention developed by the World Health Organization, called Self‐Help Plus, in preventing the development of mental disorders among Syrian refugees experiencing psychological distress in Turkey. A two‐arm, assessor‐masked RCT was conducted in two Turkish areas. Eligible participants were adult Syrian refugees experiencing psychological distress (General Health Questionnaire ≥3), but without a diagnosis of mental disorder. They were randomly assigned either to the Self‐Help Plus arm (consisting of Self‐Help Plus combined with Enhanced Care as Usual, ECAU) or to ECAU only in a 1:1 ratio. Self‐Help Plus was delivered in a group format by two facilitators over five sessions. The primary outcome measure was the presence of any mental disorder assessed by the Mini International Neuropsychiatric Interview at six‐month follow‐up. Secondary outcome measures were the presence of mental disorders at post‐intervention, and psychological distress, symptoms of post‐traumatic stress disorder and depression, personally identified psychological outcomes, functional impairment, subjective well‐being, and quality of life at post‐intervention and six‐month follow‐up. Between October 1, 2018 and November 30, 2019, 1,186 refugees were assessed for inclusion. Five hundred forty‐four people were ineligible, and 642 participants were enrolled and randomly assigned to either Self‐Help Plus (N=322) or ECAU (N=320). Self‐Help Plus participants were significantly less likely to have any mental disorders at six‐month follow‐up compared to the ECAU group (21.69% vs. 40.73%; Cramer''s V = 0.205, p<0.001, risk ratio: 0.533, 95% CI: 0.408‐0.696). Analysis of secondary outcomes suggested that Self‐Help Plus was not effective immediately post‐intervention, but was associated with beneficial effects at six‐month follow‐up in terms of symptoms of depression, personally identified psychological outcomes, and quality of life. This is the first prevention RCT ever conducted among refugees experiencing psychological distress but without a mental disorder. Self‐Help Plus was found to be an effective strategy for preventing the onset of mental disorders. Based on these findings, this low‐intensity self‐help psychological intervention could be scaled up as a public health strategy to prevent mental disorders in refugee populations exposed to ongoing adversities.