Elicitor-Induced Resistance in Tomato Plants Against Fungal Pathogens: Ultrastructure and Cytochemistry of the Induced Response

The introduction of gold cytochemistry in plant pathology has opened new avenues for accurately localizing molecules thought to play important biological functions in the plant metabolism. In an effort to understand the process associated with the induction of plant disease resistance, we investigated the effect of fungal elicitors on the cellular response of tomato root tissues during attack by Fusarium oxysporum f. sp. radicis-lycopersici, the causal agent of tomato crown and root rot. Chitosan was found to induce marked morphological and ultrastructural changes in the fungus grown in pure culture, including cytoplasm aggregation and abnormal deposition of an amorphous chitin-rich material. Examination of colonized root tissues at sites of fungal penetration revealed that a pre-treatment with chitosan (as well as with other elicitors) was associated with the expression of typical defense reactions. In the outer cortex, invading fungal cells suffered from serious damage and were frequently encircled by an electron-dense material. In the non-colonized inner cortex, strong host reactions were detected that were mainly associated with the deposition of two types of material that differed by their electron-density. Gold cytochemistry with purified β-1,3-glucanase and laccase showed that the more electron-dense material was of phenolic nature whereas the other material, occurring as deposits inserted between the phenolic aggregates, was made of callose. Application of various gold-complexed probes revealed that callose and phenolic-like compounds (likely lignin) were also the main components of newly-formed wall appositions. Results of these studies provide evidence that cytochemical approaches have the potential to significantly improve our knowledge of how plants defend themselves and how plant disease resistance can be directly enhanced by elicitors

Localization of the N-terminal domain of cauliflower mosaic virus coat protein precursor

AbstractCauliflower mosaic virus (CaMV) open reading frame (ORF) IV encodes a coat protein precursor (pre-CP) harboring an N-terminal extension that is cleaved off by the CaMV-encoded protease. In transfected cells, pre-CP is present in the cytoplasm, while the processed form (p44) of CP is targeted to the nucleus, suggesting that the N-terminal extension might be involved in keeping the pre-CP in the cytoplasm for viral assembly. This study reports for the first time the intracellular localization of the N-terminal extension during CaMV infection in Brassica rapa. Immunogold-labeling electron microscopy using polyclonal antibodies directed to the N-terminal extension of the pre-CP revealed that this region is closely associated with viral particles present in small aggregates, which we called small bodies, adjacent to the main inclusion bodies typical of CaMV infection. Based on these results, we propose a model for viral assembly of CaMV

Effects of single-dose injectable paracetamolversus propacetamol in pain management after minor gynecologic surgery: A multicenter, randomized, double-blind, active-controlled, two-parallel-group study

AbstractBackground:Intravenous administration is the route of choice for drug therapy in the immediate postoperative period. Propacetamol (ProAPAP), an injectable prodrug of paracetamol requiring reconstitution, has demonstrated efficacy in managing acute pain and fever. However, it has been associated with pain at the injection site. A stable, ready-to-use formulation of paracetamol solution infused intravenously (IV-APAP) has been developed and might be associated with less pain at the injection site compared with ProAPARObjective:The objective of this study was to assess the tolerability and efficacy of a single dose of IV APAP 1 g compared with those of a single dose of ProAPAP 2 g in patients with moderate to severe pain after minor gynecologic surgery.Methods:This single-dose, randomized, double-blind, active-controlled,2-parallel-group study was conducted at 23 hospitals and outpatient clinics in France. After minor gynecologic surgery, patients reporting moderate to severe pain were randomized to receive a single 15-minute infusion of IV-APAP 1 g or ProAPAP 2 g (bioeyuivalent doses). Tolerability was monitored using local and systemic adverse event (AE) reporting, clinical examination including vital sign measurement, and patients' ratings of acceptability of the infusion. Efficacy end points included pain intensity at 0, 1, 2, 4, and 6 hours; median time to rescue medication (defined as the time at which 50% of patients requested rescue medication); and percentage of patients requesting rescue medication. Patients' satisfaction with the study drugs was assessed using patient's global evaluation (PGE) and the percentage of patients willing to receive the treatment again.Results:Of the 163 women who were randomized, 161 received the studymedication. The IV-APAP group comprised 80 patients (mean [SD] age, 38.3 [12.8] years [range, 18.0-69.0 years]; mean [SD] weight, 61.1 [11.0] kg [range, 49.0–90.0 kg]), and the ProAPAP group comprised 81 patients (mean [SD] age, 33.9 [12.0] years [range, 18.0–67.0 years]; mean [SD] weight, 61.6 [10.2] kg [range, 42.0–95.5 kg]); the difference in mean age between the 2 groups was statistically significant (P < 0.05). The incidence of local treatment-emergent AEs (TEAEs) was significantly lower in the IV-APAP group compared with that in the ProAPAP group (7.5% vs 38.3%; P < 0.001). No between-group differences in the incidence of systemic TEAEs was found. All patients in the IV-APAP group found the infusion tolerable, compared with 95% of patients in the ProAPAP group. The median time to rescue medication was not evaluated because <50% of the patients in each group requested it. No significant differences in mean pain intensity score or percentage of patients requesting rescue medication were found between the 2 groups at any time point. The percentages of patients in the IV-APAP and ProAPAP groups who rated the study medication as good or excellent on the PGE (83.6% vs 75.6%; P < 0.05) and who were willing to receive the same treatment again (96.0% vs 81.0%; P = 0.005) were significantly higher with IV-APAP compared with ProAPAPConclusion:In these patients with moderate to severe pain after minor gynecologic surgery, a single dose of IV-APAP was associated with better local tolerability, similar analgesic efficacy, and greater patient satisfaction compared with a single bioequivalent dose of ProAPAP

A Glycemia Risk Index (GRI) of Hypoglycemia and Hyperglycemia for Continuous Glucose Monitoring Validated by Clinician Ratings

BackgroundA composite metric for the quality of glycemia from continuous glucose monitor (CGM) tracings could be useful for assisting with basic clinical interpretation of CGM data.MethodsWe assembled a data set of 14-day CGM tracings from 225 insulin-treated adults with diabetes. Using a balanced incomplete block design, 330 clinicians who were highly experienced with CGM analysis and interpretation ranked the CGM tracings from best to worst quality of glycemia. We used principal component analysis and multiple regressions to develop a model to predict the clinician ranking based on seven standard metrics in an Ambulatory Glucose Profile: very low-glucose and low-glucose hypoglycemia; very high-glucose and high-glucose hyperglycemia; time in range; mean glucose; and coefficient of variation.ResultsThe analysis showed that clinician rankings depend on two components, one related to hypoglycemia that gives more weight to very low-glucose than to low-glucose and the other related to hyperglycemia that likewise gives greater weight to very high-glucose than to high-glucose. These two components should be calculated and displayed separately, but they can also be combined into a single Glycemia Risk Index (GRI) that corresponds closely to the clinician rankings of the overall quality of glycemia (r = 0.95). The GRI can be displayed graphically on a GRI Grid with the hypoglycemia component on the horizontal axis and the hyperglycemia component on the vertical axis. Diagonal lines divide the graph into five zones (quintiles) corresponding to the best (0th to 20th percentile) to worst (81st to 100th percentile) overall quality of glycemia. The GRI Grid enables users to track sequential changes within an individual over time and compare groups of individuals.ConclusionThe GRI is a single-number summary of the quality of glycemia. Its hypoglycemia and hyperglycemia components provide actionable scores and a graphical display (the GRI Grid) that can be used by clinicians and researchers to determine the glycemic effects of prescribed and investigational treatments