A Target-Based In Vivo Test System to Identify Novel Fungicides with Mode of Action in the HOG Pathway.

Resistance management plays a key role in modern plant protection. There is a growing need to identify new fungicide targets and new modes of action. In this context, it is also mandatory to find new compounds acting on successful target locations. For the latter, so-called target-site-specific test systems emerged to search for inhibitors. Most of them are based on in vitro assays, in which interaction between a compound and a purified target protein is demonstrated. Consequently, getting essential information about potentially toxic effects in the living cell or in the whole organism is not possible. Thus, we present a fluorescent-labelled mutant strain of the rice blast fungus Magnaporthe oryzae as a rapid tool for fluorescence-based identification and visualization of fungicides in vivo with the mode of action in the high osmolarity glycerol (HOG)-signaling pathway. The HOG pathway represents an excellent target for antifungal agents such as the phenylpyrrole fungicides, since almost no relevant resistances have occurred to date, despite 30 years of extensive usage of this fungicide class.

Visualizing fungicide action: an in vivo tool for rapid validation of fungicides with target location HOG pathway.

BACKGROUND: The mitogen-activated protein kinase MoHog1p was fused with a green fluorescent protein (GFP) in the filamentous fungus Magnaporthe oryzae. The MoHOG1::GFP mutant was found to be an excellent tool visualizing in vivo fungicide-dependent translocation of MoHog1p into the nucleus. Validation of pathway specificity was achieved by generating fluorescence-labelled MoHog1p in the ΔMohik1 'loss of function' mutant strain. RESULTS: GFP-labelled MoHog1p expressed in the wildtype and in ΔMohik1 demonstrates that fludioxonil is acting on the HOG pathway and even more precisely that fungicide action is dependent on the group III histidine kinase MoHik1p. GFP-tagged MoHog1p translocated into the nucleus upon fungicide treatment in the MoHOG1::GFP mutant within seconds, but did not do so in the ΔMohik1/HOG1::GFP mutant. CONCLUSION: Here, we developed a rapid in vivo tool for fluorescent-based validation of fungicides targeting the HOG-signaling pathway. Furthermore, using the fluorescent mutants generated in this study, we are able to visualize that fungicide action is dependent on the histidine kinase MoHik1p but operates in a different mechanism of pathway activation compared to osmotic stress. © 2018 Society of Chemical Industry.

Fungicide resistance toward fludioxonil conferred by overexpression of the phosphatase gene MoPTP2 in Magnaporthe oryzae.

The fungicide fludioxonil causes hyperactivation of the Hog1p MAPK within the high-osmolarity glycerol signaling pathway essential for osmoregulation in pathogenic fungi. The molecular regulation of MoHog1p phosphorylation is not completely understood in pathogenic fungi. Thus, we identified and characterized the putative MoHog1p-interacting phosphatase gene MoPTP2 in the filamentous rice pathogen Magnaporthe oryzae. We found overexpression of MoPTP2 conferred fludioxonil resistance in M. oryzae, whereas the 'loss of function' mutant ΔMoptp2 was more susceptible toward the fungicide. Additionally, quantitative phosphoproteome profiling of MoHog1p phosphorylation revealed lower phosphorylation levels of MoHog1p in the MoPtp2p overexpression mutant compared to the wild-type strain, whereas MoHog1p phosphorylation increased in the ΔMoptp2 mutant. Furthermore, we identified a set of MoHog1p-dependent genes regulated by the MoPtp2p expression level. Our results indicate that the phosphatase MoPtp2p is involved in the regulation of MoHog1p phosphorylation and that overexpression of the gene MoPTP2 is a novel molecular mechanism of fungicide resistance.

Drug-induced Fanconi syndrome associated with fumaric acid esters treatment for psoriasis: a case series.

BACKGROUND: Fumaric acid esters (FAEs), an oral immunomodulating treatment for psoriasis and multiple sclerosis, have been anecdotally associated with proximal renal tubular dysfunction due to a drug-induced Fanconi syndrome. Few data are available on clinical outcomes of FAE-induced Fanconi syndrome. METHODS: Descriptive case series with two cases of Fanconi syndrome associated with FAE treatment diagnosed at two Dutch university nephrology departments, three cases reported at the Dutch and German national pharmacovigilance databases and six previously reported cases. RESULTS: All 11 cases involved female patients with psoriasis. The median age at the time of onset was 38 years [interquartile range (IQR) 37-46]. Patients received long-term FAEs treatment with a median treatment duration of 60 months (IQR 28-111). Laboratory tests were typically significant for low serum levels of phosphate and uric acid, while urinalysis showed glycosuria and proteinuria. Eight (73%) patients had developed a hypophosphataemic osteomalacia and three (27%) had pathological bone fractures. All patients discontinued FAEs, while four (36%) patients were treated with supplementation of phosphate and/or vitamin D. Five (45%) patients had persisting symptoms despite FAEs discontinuation. CONCLUSIONS: FAEs treatment can cause drug-induced Fanconi syndrome, but the association has been reported infrequently. Female patients with psoriasis treated long term with FAEs seem to be particularly at risk. Physicians treating patients with FAEs should be vigilant and monitor for the potential occurrence of Fanconi syndrome. Measurement of the urinary albumin:total protein ratio is a suggested screening tool for tubular proteinuria in Fanconi syndrome.

Classification of compression stockings: report of the meeting of the International Compression Club, Copenhagen.

The classification of medical elastic compression stockings (MECS) according to pressure classes varies from country to country and neither provides any information on the elastic property nor on the ambulatory interface pressure profiles of the different products. Beside elasticity, MECS are also characterized by other properties such as stiffness and hysteresis. Recent research showed that MECS behaved differently in static and ambulatory conditions. Since compression therapy is most effective during ambulation, MECS should be labelled in such a way that the user can interpret its effect during walking. The importance of a more rational classification of MECS was discussed at a conference organized by the International Compression Club (ICC) attended by medical experts and representatives from MECS manufacturers. Proposals were made for labelling the MECS according to the pressure and the stiffness in an internationally acceptable format printed on the box informing both the prescribers and the patients on its properties.

Ninety percent permanent hair reduction in transsexual patients.

Transsexualism as a condition requires hair removal. Twenty-five male-to-female transsexual patients were included in this study on epilation using the Intense Pulsed Light Source (IPLS). Patients received a varying number of treatments, depending on their response. A mean hair clearance rate of 90% was achieved in the studied patients. The average number of treatments per patient was nine. A negative correlation was found between hair removal and the age of the patient. Hair removal was also found to be more effective when the patients had not used any needle epilation. No difference in hair removal was found between transsexual patients, who were hormonal, and those who were not. Follow-up lasted an average of 44 months. This study proved that the IPLS has the potential to be effective, permanent, and painless especially in younger patients who have not used any mechanical methods for epilation before photoepilation.

Venae perforantes: a clinical review.

BACKGROUND: Although many articles on perforating veins have been published, much knowledge about these veins is lacking. OBJECTIVE: In this review relevant facts about the clinical importance of perforating veins in venous disease are described. METHODS: A literature search on English, French and German articles has been performed using literature databases like Medline, Embase and Cochrane. RESULTS: Selection criteria are described. CONCLUSION: A few conclusions are drawn: incompetent perforating veins can be of haemodynamic importance, especially in venous ulceration and (recurrent) varicose veins. The current definition of incompetent perforating veins is reflux more than 0,5 seconds (detected by Duplex ultra-sonography). Good anatomical and clinical classifications are published and should be integrated in the CEAP classification. Based on the clinical classification treatment options are described for the different types of incompetent perforating veins. Two different treatment modalities for incompetent perforating veins are surgery (SEPS) and sclerotherapy. SEPS seems to be of benefit in patients with venous ulceration and advanced CVI. Sclero-therapy (especially ultra sound guided sclerotherapy) is promising and worth further evaluation.