Metabolomics and Transcriptomics Reveal the Response Mechanisms of Mikania micrantha to Puccinia spegazzinii Infection.

Mikania micrantha is one of the worst invasive species globally and can cause significant negative impacts on agricultural and forestry economics, particularly in Asia and the Pacific region. The rust Puccinia spegazzinii has been used successfully as a biological control agent in several countries to help manage M. micrantha. However, the response mechanisms of M. micrantha to P. spegazzinii infection have never been studied. To investigate the response of M. micrantha to infection by P. spegazzinii, an integrated analysis of metabolomics and transcriptomics was performed. The levels of 74 metabolites, including organic acids, amino acids, and secondary metabolites in M. micrantha infected with P. spegazzinii, were significantly different compared to those in plants that were not infected. After P. spegazzinii infection, the expression of the TCA cycle gene was significantly induced to participate in energy biosynthesis and produce more ATP. The content of most amino acids, such as L-isoleucine, L-tryptophan and L-citrulline, increased. In addition, phytoalexins, such as maackiain, nobiletin, vasicin, arachidonic acid, and JA-Ile, accumulated in M. micrantha. A total of 4978 differentially expressed genes were identified in M. micrantha infected by P. spegazzinii. Many key genes of M. micrantha in the PTI (pattern-triggered immunity) and ETI (effector-triggered immunity) pathways showed significantly higher expression under P. spegazzinii infection. Through these reactions, M. micrantha is able to resist the infection of P. spegazzinii and maintain its growth. These results are helpful for us to understand the changes in metabolites and gene expression in M. micrantha after being infected by P. spegazzinii. Our results can provide a theoretical basis for weakening the defense response of M. micrantha to P. spegazzinii, and for P. spegazzinii as a long-term biological control agent of M. micrantha.

Marching across and beyond West Africa: First record of the stem-galling fly Cecidochares connexa (Diptera: Tephritidae) in Central Africa and the implications for biological control of Chromolaena odorata (Asteraceae).

The Neotropical invasive plant Chromolaena odorata R.M. King and H. Robinson (Asteraceae) is a serious weed in West and Central Africa and two biological control agents that have been introduced into West Africa to help reduce its impacts on agriculture and biodiversity, have established. The stem-galling fly, Cecidochares connexa (Macquart) (Diptera: Tephritidae), has spread widely across West Africa since its release in only Côte d'Ivoire, occurring in six countries. This study aimed to investigate whether the gall fly had spread further across West Africa and into Central Africa. Here, we surveyed C. odorata for C. connexa galls in Cameroon between October 2018 and October 2020, along roadsides, on farms, residential areas, and abandoned plots, encompassing various vegetation types. Additional surveys were conducted across four countries (Ghana, Togo, Benin Republic and Nigeria) in West Africa that we considered the probable pathway for the spread of the gall fly into Central Africa. Cecidochares connexa was present at five of the six locations surveyed in Cameroon, albeit in varying abundance. In Africa, these findings represent the first-ever report of C. connexa outside of West Africa. In West Africa, we recorded significant expansion in the geographic range of C. connexa, as reflected in the absent-present record of C. connexa in two locations in Nigeria and one in Ghana, as well as its occurrence in all locations surveyed in Benin Republic and Togo. Clearly, Ghana, Togo, Benin Republic and Nigeria served as the dispersal pathway of C. connexa from the release sites in Côte d'Ivoire into Cameroon, covering over 2,300 km. Following the spread and establishment of C. connexa into Cameroon, we anticipate that it will continue to spread further into other parts of Central Africa which are climatically suitable. Cecidochares connexa is currently the only biological control agent for C. odorata in Central Africa. Given that it has significantly reduced populations of C. odorata in other countries where it has established, it is expected to have a similar impact in Central Africa.

Global Actions for Managing Cactus Invasions.

The family Cactaceae Juss. contains some of the most widespread and damaging invasive alien plant species in the world, with Australia (39 species), South Africa (35) and Spain (24) being the main hotspots of invasion. The Global Cactus Working Group (IOBC GCWG) was launched in 2015 to improve international collaboration and identify key actions that can be taken to limit the impacts caused by cactus invasions worldwide. Based on the results of an on-line survey, information collated from a review of the scientific and grey literature, expertise of the authors, and because invasiveness appears to vary predictably across the family, we (the IOBC GCWG): (1) recommend that invasive and potentially invasive cacti are regulated, and to assist with this propose five risk categories; (2) recommend that cactus invasions are treated physically or chemically before they become widespread; (3) advocate the use of biological control to manage widespread invasive species; and (4) encourage the development of public awareness and engagement initiatives to integrate all available knowledge and perspectives in the development and implementation of management actions, and address conflicts of interest, especially with the agricultural and ornamental sectors. Implementing these recommendations will require global co-operation. The IOBC GCWG aims to assist with this process though the dissemination of information and experience.

Characteristics of children hospitalized with infective endocarditis.

BACKGROUND: Infective endocarditis in children is rare, and most reports describe the experience in referral centers. The purpose of our study was to assess the characteristics of children with infective endocarditis in a large national sample. METHODS AND RESULTS: We analyzed hospital discharge records with International Classification of Diseases, ninth revision, codes indicating infective endocarditis among admissions of patients <21 years of age in the Kids' Inpatient Databases 2000 and 2003; analyses for the 2 years were combined. In 1588 hospitalizations, the age distribution was bimodal, with peaks in infancy and late adolescence. The organism was coded in 632 admissions; Staphylococcus aureus was most common (57%), followed by the viridans group of streptococci (20%). Preexisting heart disease was present in 662 patients admitted (42%), among whom 81% had congenital heart disease, 8% had prosthetic valve endocarditis, and 5% had rheumatic heart disease. In-hospital mortality occurred in 84 patients (5%), 38 with preexisting heart disease. Death occurred in 12 of 25 patients (48%) with tetralogy of Fallot and pulmonary atresia, and 4 of 54 (8%) with prosthetic valve endocarditis. Among 46 deaths without preexisting heart disease, S aureus was the causative organism in 13 of 14 patients (93%) beyond infancy; among 32 infants who died, 10 (31%) were premature. CONCLUSIONS: In 2000 and 2003, we found a continuing shift in the epidemiology of pediatric infective endocarditis toward a higher proportion of children without preexisting heart disease. Risk factors for mortality included some forms of congenital heart disease and, among patients without preexisting heart disease, premature/neonatal age and S aureus as an etiologic agent.

Skip metastasis in osteosarcoma.

Skip metastasis is rare in high-grade osteosarcoma and indicates a very poor prognosis. The authors describe two patients who had high-grade osteosarcoma and skip metastasis. MRI detected the skip lesion in both patients, and both lesions were confirmed by histology. The patients were treated with adjuvant chemotherapy and radical surgical resection. Both are alive and free of disease 3 and 6 years from diagnosis.