The Role of EDTA in Lead Transport and Accumulation by Indian Mustard1

Indian mustard (Brassica juncea) plants exposed to Pb and EDTA in hydroponic solution were able to accumulate up to 55 mmol kg−1 Pb in dry shoot tissue (1.1% [w/w]). This represents a 75-fold concentration of Pb in shoot tissue over that in solution. A threshold concentration of EDTA (0.25 mm) was found to be required to stimulate this dramatic accumulation of both Pb and EDTA in shoots. Below this threshold concentration, EDTA also accumulated in shoots but at a reduced rate. Direct measurement of a complex of Pb and EDTA (Pb-EDTA) in xylem exudate of Indian mustard confirmed that the majority of Pb in these plants is transported in coordination with EDTA. The accumulation of EDTA in shoot tissue was also observed to be directly correlated with the accumulation of Pb. Exposure of Indian mustard to high concentrations of Pb and EDTA caused reductions in both the transpiration rate and the shoot water content. The onset of these symptoms was correlated with the presence of free protonated EDTA (H-EDTA) in the hydroponic solution, suggesting that free H-EDTA is more phytotoxic than Pb-EDTA. These studies clearly demonstrate that coordination of Pb transport by EDTA enhances the mobility within the plants of this otherwise insoluble metal ion, allowing plants to accumulate high concentrations of Pb in shoots. The finding that both H-EDTA and Pb-EDTA are mobile within plants also has important implications for the use of metal chelates in plant nutritional research.

Expression of a delta 9 14:0-acyl carrier protein fatty acid desaturase gene is necessary for the production of omega 5 anacardic acids found in pest-resistant geranium (Pelargonium xhortorum).

Anacardic acids, a class of secondary compounds derived from fatty acids, are found in a variety of dicotyledonous families. Pest resistance (e.g., spider mites and aphids) in Pelargonium xhortorum (geranium) is associated with high levels (approximately 81%) of unsaturated 22:1 omega 5 and 24:1 omega 5 anacardic acids in the glandular trichome exudate. A single dominant locus controls the production of these omega 5 anacardic acids, which arise from novel 16:1 delta 11 and 18:1 delta 13 fatty acids. We describe the isolation and characterization of a cDNA encoding a unique delta 9 14:0-acyl carrier protein fatty acid desaturase. Several lines of evidence indicated that expression of this desaturase leads to the production of the omega 5 anacardic acids involved in pest resistance. First, its expression was found in pest-resistant, but not suspectible, plants and its expression followed the production of the omega 5 anacardic acids in segregating populations. Second, its expression and the occurrence of the novel 16:1 delta 11 and 18:1 delta 13 fatty acids and the omega 5 anacardic acids were specific to tall glandular trichomes. Third, assays of the recombinant protein demonstrated that this desaturase produced the 14:1 delta 9 fatty acid precursor to the novel 16:1 delta 11 and 18:1 delta 13 fatty acids. Based on our genetic and biochemical studies, we conclude that expression of this delta 9 14:0-ACP desaturase gene is required for the production of omega 5 anacardic acids that have been shown to be necessary for pest resistance in geranium.

Pathogenesis of influenza virus-induced pneumonia: involvement of both nitric oxide and oxygen radicals.

The role of nitric oxide (NO) in the pathogenesis of influenza virus-induced pneumonia in mice was investigated. Experimental influenza virus pneumonia was produced with influenza virus A/Kumamoto/Y5/67(H2N2). Both the enzyme activity of NO synthase (NOS) and mRNA expression of the inducible NOS were greatly increased in the mouse lungs; increases were mediated by interferon gamma. Excessive production of NO in the virus-infected lung was studied further by using electron spin resonance (ESR) spectroscopy. In vivo spin trapping with dithiocarbamate-iron complexes indicated that a significant amount of NO was generated in the virus-infected lung. Furthermore, an NO-hemoglobin ESR signal appeared in the virus-infected lung, and formation of NO-hemoglobin was significantly increased by treatment with superoxide dismutase and was inhibited by N(omega)-monomethyl-L-arginine (L-NMMA) administration. Immunohistochemistry with a specific anti-nitrotyrosine antibody showed intense staining of alveolar phagocytic cells such as macrophages and neutrophils and of intraalveolar exudate in the virus-infected lung. These results strongly suggest formation of peroxynitrite in the lung through the reaction of NO with O2-, which is generated by alveolar phagocytic cells and xanthine oxidase. In addition, administration of L-NMMA resulted in significant improvement in the survival rate of virus-infected mice without appreciable suppression of their antiviral defenses. On the basis of these data, we conclude that NO together with O2- which forms more reactive peroxynitrite may be the most important pathogenic factors in influenza virus-induced pneumonia in mice.

Alterações na resposta imune inata e adaptativa induzidas por Escherichia coli enteroinvasora em modelo murino

Durante uma infecção, uma complexa seqüência de eventos é inkiada após a invasão do hospedeiro por microrganismos patogênicos. Escherichia coli enteroinvasora (EIEC), assim como Shigella, causa disenteria através da invasão da mucosa do cólon, levando à destruição tecidual e inflamação. Para que ocorra um processo infeccioso, porém, são necessários inóculos de 102 Shigella e 106 EIEC. Foram avaliados aspectos da resposta inflamatória desencadeada pela infecção por EIEC em modelo murino, comparativamente a Shigella. A infecção de macrófagos J774 por EIEC resultou em fagocitose bacteriana, comprometimento da viabilidade do macrófago e produção de citocinas. Macrófagos de camundongos C57BU6 infectados com EIEC produziram NO, que parece ser importante no controle da infecção. Foi observado que camundongos INOS nocaute apresentaram maior produção de citocinas pró-inflamatórias e maior letalidade após infecção do que os selvagens. EIEC induziu a migração de granulócitos e monócitos para o peritônio, e a secreção de citocinas por estas células. Houve proliferação de linfócitos em resposta aos antígenos solúveis de EIEC, mas não foi detectada produção de citocinas por estes linfócitos.Comparativamente a Shigella, EIEC escapou mais lentamente do macrófago, induziu menor produção de citocinas pró-inflamatórias e NO, e menor ativação dos linfócitos T. Estes dados sugerem o desafio com EIEC desencadeia uma resposta menos severa no hospedeiro do que Shigella, o que explicaria a forma mais branda de disenteria e resolução mais rápida do processo infeccioso causado por EIEC.

El uso de apósitos hidrocelulares de la gama Allevyn® en heridas agudas: resultados a partir del estudio AURIGA-04 en Atención Primaria

Aunque los apósitos de cura en ambiente (CAH) húmedo se han utilizado predominantemente en heridas crónicas, ello no es óbice para que su uso en heridas agudas permita solucionar algunos problemas, como el conseguir un ambiente óptimo que facilite la migración epitelial, así como una adecuada protección de las heridas y una correcta gestión del exudado. Es por ello que, dentro del marco del estudio AURIGA-04, nos planteamos la realización de un estudio prospectivo observacional, abierto y multicéntrico, de medidas repetidas en una cohorte de pacientes que presentan heridas agudas de diversa etiología en el que se incluyeron pacientes con heridas traumáticas, quirúrgicas o quemaduras tratados por profesionales de Atención Primaria, con el objetivo de generar evidencias acerca de la utilización de apósitos de CAH, en concreto, de la gama de apósitos hidrocelulares Allevyn®, en el tratamiento de heridas agudas. Se consideraron como criterios de exclusión heridas con signos clínicos de infección. Solo se incluyó una lesión por paciente. En el caso de los pacientes con heridas agudas, la muestra a estudio quedó compuesta por 61 pacientes con una edad media de 71,1 años; 36 casos corresponden a mujeres (60%). El estado general de salud de la muestra era bueno en un 49,1% de los casos y prácticamente la totalidad de los pacientes presentaba pluripatología. Un 10% de los pacientes consumía fármacos que podían interferir en la cicatrización y un 6% presentaba malnutrición. El 67,2% de las lesiones eran heridas traumáticas, el 24,6% quirúrgicas y un 8,2% quemaduras. Un 37% de las lesiones fueron clasificadas como superficiales y el 63% restante como profundas. Presentaban 64 días de evolución previa a su inclusión en el estudio y una superficie media de 23,34 cm2. Los pacientes permanecieron en el estudio un promedio de 43,6 días, con una cadencia de cambios de apósito cada 2,7 días. Durante el estudio cicatrizaron el 63,9% de las heridas, en un promedio de 40,9 días. La superficie inicial de las lesiones mostró una reducción significativa a lo largo del seguimiento (inicial: 23,34 cm2, final: 4,27 cm2, p ≤ 0,001). En los modelos de regresión de Cox, sólo resultó estadísticamente significativa la edad del paciente, en el grupo de lesiones traumáticas (RR: –0,03, p= 0,039). Durante el período de seguimiento, un 80,3% de los pacientes fue tratado en combinación con Intrasite Conformable®, Iruxol Mono® o la combinación de ambos productos. Los profesionales que realizaron las curas con Allevyn® valoraron muy favorablemente su manejo durante todo el estudio; así, en más del 96% de los cambios se consideró fácil de colocar, en el 100% indoloro y también en el 100% de fácil retirada. A la vista de los resultados, los apósitos de CAH y, en concreto, la gama de apósitos Allevyn®, tienen una clara aplicación en el caso de las heridas agudas, permitiendo un óptimo abordaje local de las lesiones, proporcionando unos niveles óptimos de humedad, pH y temperatura para las células implicadas en el proceso de cicatrización. Así, se promueve la formación de tejido de granulación y facilita la epitelización, además de proteger la herida ante traumatismos y gérmenes.

Surgery, its principles and practice,

"The first six volumes of this work recorded the progress of Surgery down to 1913. Then came the Great War ... Hence, immediately after the Armistice ... I began to assemble a full staff of experts, whose work appears in Volumes VII and VIII."--Preface, v.7, 1921.

The anatomy of the peritonaeum /

Outlines of the embryological development of the abdominal viscera.

Detection of surfactant protein A (SP-A) and surfactant protein D (SP-D) in equine synovial fluid with immunoblotting

Once considered unique to the lung, surfactant proteins have been clearly identified in the intestine and peritoneum and are suggested to exist in several other organs. In the lung, surfactant proteins assist in the formation of a monolayer of surface-active phospholipid at the liquid-air interface of the alveolar lining, reducing the surface tension at this surface. In contrast, surface-active phospholipid adsorbed to articular surfaces has been identified as the load-bearing boundary lubricant of the joint. This raises the question of whether surfactant proteins in synovial fluid (SF) are required for the formation of the adsorbed layer in normal joints. Proteins from small volumes of equine SF were resolved by 1- and 2-dimensional polyacrylamide gel electrophoresis and detected by Western blotting to investigate the presence of surfactant proteins. The study showed that surfactant proteins A and D (SP-A and SP-D) are present in the SF of normal horses. We suggest that, like surface-active phospholipid, SP-A and SP-D play a significant role in the functioning of joints. Next will be clarification of the roles of surfactant proteins as disease markers in a variety of joint diseases, such as degenerative joint disease and inflammatory problems.

LPS regulates a set of genes in primary murine macrophages by antagonising CSF-1 action

We previously reported that bacterial products such as LPS and CpG DNA down-modulated cell surface levels of the Colony Stimulating Factor (CSF)-1 receptor (CSF-1R) on primary murine macrophages in an all-or-nothing manner. Here we show that the ability of bacterial products to down-modulate the CSF-IR rendered bone marrow-derived macrophages (BMM) unresponsive to CSF-1 as assessed by Akt and ERK 1/2 phosphorylation. Using toll-like receptor (th-)9 as a model CSF-1-repressed gene, we show that LPS induced tlr9 expression in BMM only when CSF-1 was present, suggesting that LPS relieves CSF-1-mediated inhibition to induce gene expression. Using cDNA microarrays, we identified a cluster of similarly CSF-1 repressed genes in BMM. By real time PCR we confirmed that the expression of a selection of these genes, including integral membrane protein 2B (itm2b), receptor activity-modifying protein 2 (ramp2) and macrophage-specific gene 1 (mpg-1), were repressed by CSF-1 and were induced by LPS only in the presence of CSF-1. This pattern of gene regulation was also apparent in thioglycollate-elicited peritoneal macrophages (TEPM). LPS also counteracted CSF-1 action to induce mRNA expression of a number of transcription factors including interferon consensus sequence binding protein 1 (Icsbp1), suggesting that this mechanism leads to transcriptional reprogramming in macrophages. Since the majority of in vitro studies on macrophage biology do not include CSF-1, these genes represent a set of previously uncharacterised LPS-inducible genes. This study identifies a new mechanism of macrophage activation, in which LPS (and other toll-like receptor agonists) regulate gene expression by switching off the CSF-1R signal. This finding also provides a biological relevance to the well-documented ability of macrophage activators to down-modulate surface expression of the CSF-1R. (C) 2005 Elsevier GmbH. All rights reserved.

Identification of the causal agent of pistachio dieback in Australia

Symptoms associated with pistachio dieback in Australia include decline (little or no current season growth), xylem staining in shoots two or more years old, trunk mu and limb lesions (often covered by black, superficial fungal growth), excessive exudation of resin, dieback and death of the tree. Bacteria belonging to the genus Xanthomonas have been suggested as the causal agent. To confirm the constant association between these bacteria and the disease syndrome, the absence of other pathogens and the identity of the pathogen, we performed a series of isolations and pathogenicity tests. The only microorganism consistently isolated from diseased tissue was a bacterium that produced yellow, mucoid colonies and displayed morphological and cultural characteristics typical of the genus Xanthomonas. Database comparisons of the fatty acid and whole-cell protein profiles of five representative pistachio isolates indicated that they all belonged to X. translucens, but it was not possible to allocate the isolates to pathovar. Pathogenicity tests on cereals and grasses supported this identification. However, Koch's postulates have been only partially fulfilled because not all symptoms associated with pistachio dieback were reproduced on inoculated two-year-old pistachio trees. While discolouration was observed, dieback, excessive resinous exudate and trunk and limb lesions were not produced; expression of these symptoms may be delayed, and long-term monitoring of a small number of inoculated trees is in progress.

Development of an animal repellent - selection, efficacy and presentation

Under some circumstances it may be desirable to repel herbivorous pests (e. g. goats and wallabies) from plants (e. g. horticultural or forestry seedlings) rather than to kill them. These circumstances may include using these animals as a resource at a later time, and there may also be welfare, public perception or legislative issues where repelling animals from particular plants or area is preferable to killing them. The first experiment tested the efficacy of 5 different materials (tiger fecal extract, maggot brew-the liquid exudate from a flyblown goat, capsaicin, dog urine, and burnt goat hair, skin and carcass+fat) to repel groups of goats in a feedlot pen from 1 trough of feed when another trough of feed was available to them to eat. Each repellent was tested on 5 groups of mixed age female goats for periods of 3 days. All 5 groups were exposed to the 5 repellents. Both tiger fecal extract and maggot brew reduced intake of feed from the 'protected' feed trough and significantly (P < 0.05) delayed 'normal' feeding behaviour by more than 5 h from that trough. The repellents became less effective with repeated use even with different groups of goats. The reduction in effectiveness was indicated by higher intakes of feed and earlier feeding from the protected trough. This habituation to the repellents, where the effectiveness is reduced with repeated exposure, is of concern. In the second experiment, we selected the most effective repellent (tiger fecal extract) and tested its efficacy under similar conditions, after the repellent had been mixed with a carrier (bentonite) in an endeavour to increase the duration of its effectiveness. This repellent was significantly more effective in repelling groups of 3 goats in a feedlot pen from 1 trough of feed for 3 days, when another trough of feed was available to them to eat.

Functional significance of dauciform roots: exudation of carboxylates and acid phosphatase under phosphorus deficiency in Caustis blakei (Cyperaceae)

Caustis blakei produces an intriguing morphological adaptation by inducing dauciform roots in response to phosphorus (P) deficiency. We tested the hypothesis that these hairy, swollen lateral roots play a similar role to cluster roots in the exudation of organic chelators and ectoenzymes known to aid the chemical mobilization of sparingly available soil nutrients, such as P. Dauciform-root development and exudate composition (carboxylates and acid phosphatase activity) were analysed in C. blakei plants grown in nutrient solution under P-starved conditions. The distribution of dauciform roots in the field was determined in relation to soil profile depth and matrix. The percentage of dauciform roots of the entire root mass was greatest at the lowest P concentration ([P]) in solution, and was suppressed with increasing solution [P], while in the field dauciform roots were predominately located in the upper soil horizons, and decreased with increasing soil depth. Citrate was the major carboxylate released in an exudative burst from mature dauciform roots, which also produced elevated levels of acid phosphatase activity. Malonate was the dominant internal carboxylate present, with the highest concentration in young dauciform roots. The high concentration of carboxylates and phosphatases released from dauciform roots, combined with their prolific distribution in the organic surface layer of nutrient-impoverished soils, provides an ecophysiological advantage for enhancing nutrient acquisition.

The targeting of corticosteroids to inflamed tissues

In recent years, much interest has focused on the beneficial effects of administering potentially harmful therapeutic agents in drug carriers so as to reduce their toxic side effects. Rheumatoid arthritis is a chronic systemic disease with progressive destruction of the Joints and long term patient disability, Corticosteroids have been shown to retard the progression of Joint destruction but are limited in their use due to adverse side effects,This project, following the line of investigation started by other workers, was designed to study the use of microspheres to deliver corticosteroids to inflamed tissues by both the oral and intravenous routes. Hydrocortisone (HC)-loaded albumin microspheres were prepared by three different methods, by direct incorporation of HC within the particles, by indirect incorporation of HC by the enzymatic conversion of hydrocortisone-21-phosphate (H-21-P) to HC within the particles, and by the adsorption of HC onto the surface. HC was also loaded with PLA microspheres. The level of corticosteriod loading and in vitro release from microspheres was determined by HPLC analysis. A reversed-phase, ion-pairing HPLC method was developed to simultaneously measure both HC and H-21-P. The highest level of corticosteroid loading was achieved using the incorporation of H-21-P with enzymatic conversion to HC method. However, HPLC analysis showed only 5% of the incorporated steroid was HC. In vitro release rates of steroid from albumin microspheres showed >95% of incorporated steroid was released within 2 hours of dissolution. Increasing the protein:steroid ratio, and the temperature and duration of microsphere stabilization, had little effect on prolonging drug release. In vivo studies, using the carrageenan-induced rat hind-paw model of inflammation, indicated steroid-incorporated microspheres administered both orally and intraperitoneally were not therapeutically advantageous when compared to equivalent free steroid doses. The ability of orally and intravenously dosed [125I]~albumin microspheres (2.67 μm mean diameter) to accumulate in acutely and chronically inflamed tissues was investigated, The subcutaneous air-pouch was the model of inflammation used, with carrageenan as the inflammatory stimulus. Acute and chronic inflammation was shown to be consistently formed  in pouch tissues in terms of cell infiltration and fluid exudate formation in the pouch cavity. Albumin microspheres were shown to accumulate in the inflamed tissues and pouch fluids after both oral and intravenous administration. Preliminary, confirmatory studies using latex microspheres and quantitation by GPC analysis, also indicated microsphere accumulation in both acutely and chronically inflamed air-pouch tissues. tntl lUr"'poucbtis,sues; The results indicate the uptake and transfer of microspheres across the gastrointestinal tract into the circulation and their migration through disrupted endothelium and basement membranes at the inflamed sites. , .

How accurate are photographic surrogate markers used to detect macular oedema in the english national Screening Programme?

Introduction: Macular oedema is not directly visible on digital photographs used in screening. Photographic surrogate markers are used to detect patients who may have macular oedema. Evidence suggests that only around 10% of patients with these surrogate markers referred to an ophthalmologist have macular oedema when examined by slit-lamp biomicroscopy. Purpose: The purpose of this audit was to determine how many patients with surrogate markers were truly identified by optical coherence tomography (OCT) as having macular oedema. Method: Data were collected from patients attending digital diabetic retinopathy screening. Patients who presented with surrogate markers for macular oedema also had an OCT scan. The fast macula scan on the Stratus OCT was used and an ophthalmologist reviewed the scans to determine whether macular oedema was present. Results: Out of 66 patients with maculopathy defined as haemorrhages or microaneurysms within one optic disc diameter (DD) of the fovea and visual acuity (VA) worse than 6/9 11 (17%) showed thickening on the OCT, only 4 (6%) had macular oedema. None required laser. Out of 155 patients with maculopathy defined as any exudate within one DD of the fovea or circinate within two DD 45 (29%) showed thickening on the OCT of these 27% required laser. Conclusion: OCT is a useful tool in screening to help identify those who need a true referral to ophthalmology for maculopathy. If exudate is present the chance of having macular oedema and requiring laser treatment is greater than the presence of microaneurysms within one DD and reduced VA.