Proteinase-activated receptors, targets for kallikrein signaling

Serine proteinases like thrombin can signal to cells by the cleavage/activation of proteinase-activated receptors (PARs). Although thrombin is a recognized physiological activator of PAR(1) and PAR(4), the endogenous enzymes responsible for activating PAR(2) in settings other than the gastrointestinal system, where trypsin can activate PAR(2), are unknown. We tested the hypothesis that the human tissue kallikrein (hK) family of proteinases regulates PAR signaling by using the following: 1) a high pressure liquid chromatography (HPLC)-mass spectral analysis of the cleavage products yielded upon incubation of hK5, -6, and -14 with synthetic PAR N-terminal peptide sequences representing the cleavage/activation motifs of PAR(1), PAR(2), and PAR(4); 2) PAR-dependent calcium signaling responses in cells expressing PAR(1), PAR(2), and PAR(4) and in human platelets; 3) a vascular ring vasorelaxation assay; and 4) a PAR(4)-dependent rat and human platelet aggregation assay. We found that hK5, -6, and -14 all yielded PAR peptide cleavage sequences consistent with either receptor activation or inactivation/disarming. Furthermore, hK14 was able to activate PAR(1), PAR(2), and PAR(4) and to disarm/inhibit PAR(1). Although hK5 and -6 were also able to activate PAR(2), they failed to cause PAR(4)-dependent aggregation of rat and human platelets, although hK14 did. Furthermore, the relative potencies and maximum effects of hK14 and -6 to activate PAR(2)-mediated calcium signaling differed. Our data indicate that in physiological settings, hKs may represent important endogenous regulators of the PARs and that different hKs can have differential actions on PAR(1), PAR(2), and PAR(4).

Vibrational spectroscopy of a compound with a CS7 ring

The product of the Asinger reaction between elemental sulfur, n-butylamine and acetophenone is 8-(n-butylaminophenylmethyliden)-1,2,3,4,5,6,7-heptathiocane which contains a CS7 ring. A combination of infrared, Raman and inelastic neutron scattering spectroscopies with periodic density functional theory calculations is used to provide a complete assignment of the vibrational spectra of this unusual species. The similarity between the Raman spectra of the compound and that of elemental sulfur is particularly striking. Copyright (C) 2009 John Wiley & Sons, Ltd.

Wiggle-match dating of tree-ring sequences

Given the non-monotonic form of the radiocarbon calibration curve, the precision of single C-14 dates on the calendar timescale will always be limited. One way around this limitation is through comparison of time-series, which should exhibit the same irregular patterning as the calibration curve. This approach can be employed most directly in the case of wood samples with many years growth present (but not able to be dated by dendrochronology), where the tree-ring series of unknown date can be compared against the similarly constructed C-14 calibration curve built from known-age wood. This process of curve-fitting has come to be called "wiggle-matching." In this paper, we look at the requirements for getting good precision by this method: sequence length, sampling frequency, and measurement precision. We also look at 3 case studies: one a piece of wood which has been independently dendrochronologically dated, and two others of unknown age relating to archaeological activity at Silchester, UK (Roman) and Miletos, Anatolia (relating to the volcanic eruption at Thera).

High resolution photoacoustic overtone spectroscopy of monofluoroacetylene, HCCF, with a titanium:sapphire ring laser

Intracavity photoacoustic overtone spectrum of monofluoroacetylene, HCCF, has been recorded in the wave number region 10 750–14 500 cm−1 with a titanium:sapphire ring laser. The spectrum contains many dense vibration–rotation band systems which can be resolved with Doppler limited resolution. Altogether 58 individual overtone bands have been analyzed rotationally. Many of the observed bands show perturbations of which some have been attributed to anharmonic resonance interactions. A Fermi resonance model based on conventional rectilinear normal coordinate theory has been used to assign vibrationally bands from this work and from earlier studies. Many of the observed vibrational term values and rotational constants can be reproduced well with this model. The results show the importance of the Fermi resonance interactions at the high overtone excitations.

Antifungal activity of Bacillus subtilis filtrate to control Fusarium oxysporum f.sp. lentis, the causal organism of lentil vascular wilt

In dual cultures, the supernatant filtrate of the biological control agent Bacillus subtilis was evaluated against (Fusarium oxysporum f.sp. lentis) the causal organism of lentil vascular wilt. The antagonistic activity was evaluated as percent reduction of fungal growth (certainly due, in part, to the antifungal metabolites produced by the antagonistic bacterium). The in-vitro experiments showed that B. subtilis filtrate, whether solid or liquid media, had a strong inhibiting activity on the spore germination and mycelial growth of F. oxysporum f. sp. lentis. In a glasshouse experiment, soil was drenched with B. subtilis filtrate at 30 ml/kg (vol/wt) around seedlings of a susceptible lentil line (ILL 4605). In this treatment there was only 31% mortality compared with 100% kill of plants in the control treatment (P≤0.05).

Formulation and delivery of the bacterial antagonist Bacillus subtilis for management of lentil vascular wilt caused by Fusarium oxysporum f. sp lentis

Different formulations of Bacillus subtilis were prepared using standard laboratory protocols. Bacillus subtilis survived in glucose and talc powders at 8.6 and 7.8 log(10) CFU/g, respectively, for 1 year of storage at room temperature compared with 3.5 log(10) CFU/g on a peat formulation. Glasshouse experiments using soil and seed treatments were conducted to test the efficacy of B. subtilis for protecting lentil against the wilt disease caused by Fusariumoxysporum f. sp. lentis. Seed treatments with formulations of B. subtilis on glucose, talc and peat significantly enhanced its biocontrol activity against Fusarium compared with a treatment in which spores were applied directly to seed. The formulations decreased disease severity by reducing colonization of plants by the pathogen, promoting their growth and increased the dry weight of lentil plants. Of these treatments the glucose and talc-based powder formulations were more effective than the peat formulation and the spore application without a carrier. It was shown that the B. subtilis spores applied with glucose were viable for longer than those applied with other carriers. Seed treatment with these formulated spores is an effective delivery system that can provide a conducive environment for B. subtilis to suppress vascular wilt disease on lentil and has the potential for utilization in commercial field application.

The survival advantage of milk and dairy consumption: An overview of evidence from cohort studies of vascular diseases, diabetes and cancer

Objectives: To conduct it detailed evaluation, with meta-analyses, of the published evidence on milk and dairy consumption and the incidence of vascular diseases and diabetes. Also to summarise the evidence on milk and dairy consumption and cancer reported by the World Cancer Research Fund and then to consider the relevance of milk and dairy consumption to survival in the UK, a typical Western community. Finally, published evidence on relationships with whole milk and fat-reduced milks was examined. Methods: Prospective cohort studies of vascular disease and diabetes with baseline data on milk or dairy consumption and a relevant disease outcome were identified by searching MEDLINE, and reference lists in the relevant published reports. Meta-analyses of relationships in these reports were conducted. The likely effect of milk and dairy consumption on survival was then considered, taking into account the results of published overviews of relationships of these foods with cancer. Results: From meta-analysis of 15 studies the relative risk of stroke and/or heart disease in subjects with high milk or dairy consumption was 0.84 (95% CI 0.76, 0,93) and 0.79 (0.75, 0.82) respectively, relative to the risk in those with low consumption. Four studies reported incident diabetes as an outcome, and the relative risk in the Subjects with the highest intake of milk or diary foods was 0.92 (0.86, 0.97). Conclusions: Set against the proportion of total deaths attributable to the life-threatening diseases in the UK, vascular disease, diabetes and cancer, the results of meta-analyses provide evidence of an overall survival advantage from the consumption of milk and dairy foods.

Enhancement of germination of spores of Verticillium dahliae and Fusarium oxysporum esp vasinfectum in vascular fluid from cotton plants infected with the root-knot nematode

Root-knot nematode [RKN] (Meloidogyne incognita) can increase the severity of Verticillium (V dahliae) and Fusarium (F oxysporum f.sp. vasinfectum) wilt diseases in cotton (Gossypium hirsutum). This study was conducted to determine some of the physiological responses caused by nematode invasion that might decrease resistance to vascular wilt diseases. The effect of RKN was investigated on spore germination and protein, carbohydrate and peroxidase content in the xylem fluids extracted from nematode-infected plants. Two cotton cultivars were used with different levels of resistance to both of the wilt pathogens. Spore germination was greater in the xylem fluids from nematode-infected plants than from nematode-free plants. The effect on spore germination was greater in the Fusarium-resistant cultivar (51%). Analysis of these fluids showed a decrease in total protein and carbohydrate levels for both wilt-resistant cultivars, and an increase in peroxidase concentration. Fluids from nematode-free plants of the Verticillium-resistant cultivar contained 46% more peroxidase than the Fusarium-resistant cultivar. The results provide further evidence that the effect of RKN on vascular wilt resistance is systemic and not only local. Changes in metabolites in the xylem pass from the root to the stem, accelerating disease development.

Vascular plant diversity and climate change in the alpine zone of the Lefka Ori, Crete

The aim of this study is to analyse the vascular flora and the local climate along an altitudinal gradient in the Lefka Ori massif Crete and to evaluate the potential effects of climate change on the plant diversity of the sub-alpine and alpine zones. It provides a quantitative/qualitative analysis of vegetation-environment relationships for four summits along an altitude gradient on the Lefka Ori massif Crete (1664-2339 m). The GLORIA multi-summit approach was used to provide vegetation and floristic data together with temperature records for every summit. Species richness and species turnover was calculated together with floristic similarity between the summits. 70 species were recorded, 20 of which were endemic, belonging to 23 different families. Cretan endemics dominate at these high altitudes. Species richness and turnover decreased with altitude. The two highest summits showed greater floristic similarity. Only 20% of the total flora recorded reaches the highest summit while 10% is common among summits. Overall there was a 4.96 degrees C decrease in temperature along the 675 m gradient. Given a scenario of temperature increase the ecotone between the sub-alpine and alpine zone would be likely to have the greatest species turnover. Southern exposures are likely to be invaded first by thermophilous species while northern exposures are likely to be more resistant to changes. Species distribution shifts will also depend on habitat availability. Many, already threatened, local endemic species will be affected first.

Induction of heme oxygenase 1 by moderately oxidized low-density lipoproteins in human vascular smooth muscle cells: role of mitogen-activated protein kinases and Nrf2

Oxidized low-density lipoproteins (LDL) play a central role in atherogenesis and induce expression of the antioxidant stress protein heme oxygenase 1 (HO-1). In the present study we investigated induction of HO-1 and adaptive increases in reduced glutathione (GSH) in human aortic smooth muscle cells (SMC) in response to moderately oxidized LDL (moxLDL, 100 mu g protein/ml, 24 h), a species containing high levels of lipid hydroperoxides. Expression and activity of HO-1 and GSH levels were elevated to a greater extent by moxLDL than highly oxidized LDL but unaffected by native or acetylated LDL. Inhibitors of protein kinase C (PKC) or mitogen-activated protein kinases (MAPK) p38(MAPK) and MEK or c-jun-NH2-terminal kinase (JNK) significantly attenuated induction of HO-1. Phosphorylation of p38(MAPK), extracellular signal-regulated kinase (ERK1/2), or JNK and nuclear translocation of the transcription factor Nrf2 were enhanced following acute exposure of SMC to rnoxLDL (100 mu g proteiri/ml, 1-2 h). Pretreatment of SMC with the antioxidant vitamin C (100 mu M, 24 h) attenuated the induction of HO-1 by moxLDL. Native and oxidized LDL did not alter basal levels of intracellular ATP, mitochondrial dehydrogenase activity, or expression of the lectin-like oxidized LDL receptor (LOX-1) in SMC. These findings demonstrate for the first time that activation of PKC, p38(MAPK), JNK, ERK1/2, and Nrf2 by oxidized LDL in human SMC leads to HO-1 induction, constituting an adaptive response against oxidative injury that can be ameliorated by vitamin C. (C) 2005 Elsevier Inc. All rights reserved.