The phylogenetically-related pattern recognition receptors EFR and XA21 recruit similar immune signaling components in monocots and dicots

During plant immunity, surface-localized pattern recognition receptors (PRRs) recognize pathogen-associated molecular patterns (PAMPs). The transfer of PRRs between plant species is a promising strategy for engineering broad-spectrum disease resistance. Thus, there is a great interest in understanding the mechanisms of PRR-mediated resistance across different plant species. Two well-characterized plant PRRs are the leucine-rich repeat receptor kinases (LRR-RKs) EFR and XA21 from Arabidopsis thaliana (Arabidopsis) and rice, respectively. Interestingly, despite being evolutionary distant, EFR and XA21 are phylogenetically closely related and are both members of the sub-family XII of LRR-RKs that contains numerous potential PRRs. Here, we compared the ability of these related PRRs to engage immune signaling across the monocots-dicots taxonomic divide. Using chimera between Arabidopsis EFR and rice XA21, we show that the kinase domain of the rice XA21 is functional in triggering elf18-induced signaling and quantitative immunity to the bacteria Pseudomonas syringae pv. tomato (Pto) DC3000 and Agrobacterium tumefaciens in Arabidopsis. Furthermore, the EFR:XA21 chimera associates dynamically in a ligand-dependent manner with known components of the EFR complex. Conversely, EFR associates with Arabidopsis orthologues of rice XA21-interacting proteins, which appear to be involved in EFR-mediated signaling and immunity in Arabidopsis. Our work indicates the overall functional conservation of immune components acting downstream of distinct LRR-RK-type PRRs between monocots and dicots

Prevalence of HIV infection among the patients with an avascular necrosis of the femoral head in Ouagadougou, Burkina Faso

Objective: To study the prevalence of HIV infection among the risk factors associated with the avascular necrosis of the femoral head in Ouagadougou, Burkina Faso. Design: Multicenter retrospective study. Setting: Rheumatology consultations and Orthopedic-Traumatology Surgery Department Of The University Hospital Yalgado Ouédraogo, at the Medico-Surgical Private Clinic “Notre Dame de la Paix” and the Medical Center ‘Paul VI’ in Ouagadougou, Burkina Faso. Patients and methods: The study was conducted on recorded cases from January 2007 to December 2009. All patients received during the study period for an avascular necrosis of the femoral head that was confirmed by X-ray and / or CT were included. The search for HIV antibodies was performed for all patients by the ELISA test confirmed by the Western Blot test. Results: There were 79 men (56%) and 62 women (44%). It shows a sex ratio of 1.2. The average age of patients was 43.95 ± 15.36 years with extremes of 7 and 79 years. The average duration of disease before diagnosis was 6 ± 6.5 years with extremes of 1 and 39 years. The affected area involved the left hip in 67 cases (47.5%), the right hip in 48 cases (34%) and was bilateral in 26 cases (18.5%). Among the risk factors, alcohol consumption was reported in 30/67 (44.8%), steroids in 09/67 (13.4%), sickle cell disease in 12/141 (8.5%). Six patients (4.25%) among the 141 had an HIV infection. Conclusion: HIV infection has a place among the risk factors of an avascular necrosis of the femoral head. A HIV serology test should be systematically carried out in all patients with an avascular necrosis of the femoral head in sub-Saharan Africa, particularly in the absence of other risk factors. Key words: Avascular necrosis of the femoral head, HIV, sickle cell disease, sub-Saharan Africa

Site-specific management is crucial to managing Mikania micrantha

Summary Increasingly, weeds have been taking on global distributions. With the proliferation of invasive weeds has come the challenge of managing these species over broad geographical regions, with diverse habitats and political jurisdictions. Here, we review the management of Mikania micrantha Kunth (Asteraceae; mile-a-minute) throughout its invaded range, extending through most of the Pacific islands and southern and south-east Asia. Context matters when determining the best course of action for managing M. micrantha, as it has invaded a large variety of agricultural and natural systems. In Queensland, Australia and Florida, USA, M. micrantha has been targeted in relatively successful eradication campaigns, highlighting the importance of early detection and rapid response methods, while elsewhere in its invaded range, populations are either still increasing or showing limited signs of decline. An inter-regional approach to research and management should incorporate successful management strategies employed throughout the invaded range including, but not limited to, chemical and cultural control practices, manual and mechanical control, classical biological control using the rust fungus Puccinia spegazzinii, plant–plant competition and integrated approaches utilising two or more control methods concurrently. Additional knowledge of M. micrantha genetics is required to determine if management approaches could be fine-tuned for particular populations. Countries bordering the Mekong River formed a network in 2011 to co-ordinate the management of invasive species such as M. micrantha. Expanding such a collaborative approach to other regions could further reduce populations of M. micrantha and limit its spread