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1 Mesangial cells play an active role in the in¯ammatory response to glomerular injury. We have studied in cultured human mesangial cells (CHMC) several eects of 9-cis retinoic acid (9-cRA), an activator of both retinoic acid receptors (RARs) and retinoid X receptors (RXRs). 2 9-cRA inhibited foetal calf serum-induced CHMC proliferation. It also prevented CHMC death induced by the in¯ammatory mediator H 2 O 2 . This preventive eect was not due to any increase in H 2 O 2 catabolism and it persisted even when both catalase and glutathione synthesis were inhibited. Finally, 9-cRA diminished monocyte adhesion to FCS-stimulated CHMC. Interestingly, the retinoid also inhibited in FCS-stimulated cells the protein expression of two mesangial adhesion molecules, ®bronectin and osteopontin, but it did not modify the protein expression of intercellular adhesion molecule-1 and vascular adhesion molecule-1. 3 All major RARs and RXRs isotypes were expressed in CHMC regardless of the presence or absence of 9-cRA. Transcripts to RAR-a, RAR-b and RXR-a increased after incubation with 9-cRA whereas RXR-g was inhibited, suggesting a major role for RARs and RXRs in 9-cRA-antiin¯ammatory eects. 4 9-cRA was toxic only at 50 mM (a concentration 50 ± 5000 times higher than required for the eects above). Cell death occurred by apoptosis, whose onset was associated with a pronounced increase in catalase activity and reduced glutathione content, being more eectively induced by alltrans retinoic acid. Modulation of the oxidant/antioxidant balance failed to inhibit apoptosis. 5 We conclude that mesangial cells might be a target for the treatment of in¯ammatory glomerulopathies with 9-cRA.

Cassava (Manihot esculenta Crantz) has been traditionally grown as a subsistence crop in Laos, but in recent years cassava cultivation in this country has expanded and is becoming a ‘cash crop’ for farmers (Malik et al., 2020). This also means that cassava vegetative seed (stakes) is rapidly multiplied and distributed. One of the most important diseases affecting cassava in the world is the Cassava Mosaic Disease (CMD), caused by several species of begomoviruses and disseminated by infected stakes or vectored by the whitefly Bemisia tabaci (Legg et al., 2014). Sri Lankan cassava mosaic virus (SLCMV), a bipartite begomovirus, is the virus species causing CMD in Southeast Asia (SEA) and is widespread in Cambodia, Vietnam, Thailand and south China (Siriwan et al., 2020). During field surveys on July 12 to 14, 2020, the team in south Laos, surveyed 8 fields along the border with Cambodia, in the southern provinces of Attapeu and Champassack and identified CMD symptoms (Supplementary Figure 1A) in only one of the fields, located at Kong District of the Champassack province (GPS coordinates 13.94325, 105.99102). From these 8 fields, samples were collected from every third plant in an X pattern. Photographs from each sampled plant were taken and uploaded into CIAT’s PestDisPlace platform (https://pestdisplace.org), for CMD symptom confirmation (Supplementary Figure 1B). Leaf samples were sent to the laboratory for PCR using primers SLCMV-F 5’-ATGTCGAAGCGACCAGCAGATATAAT-3’ and SLCMV-R 5’-TTAATTGCTGACCGAATCGTAGAAG-3’ targeting the AV1 gene (Dutt et al., 2005), following the protocol described in Siriwan et al. (2020) and primers SLCMV-B-F1 5’-ACCGGATGGCCGCGCCCCCCTCT-3’ and SLCMV-B-606R 5’-CACCTACCCTGTTATCGCTAAG-3’ targeting part of the BV1 gene. Out of 60 samples collected for the field in Kong district, eleven (18.3%) resulted PCR positive to SLCMV (to DNA-A and DNA-B) but only four plants (6.7%) showed symptoms of CMD (see Supplementary Figure 1B and 1C). None of the samples in the other seven fields had CMD symptoms nor was SLCMV detected in any of these plants. Furthermore, the presence of CMD symptoms in the old leaves of the plants in the affected field suggests that the virus was introduced with contaminated stakes. The complete bipartite genome of one isolate (Champ1), was amplified by Rolling Circle Amplification and sequenced with the nanopore MinION technology as described by Leiva et al. (2020). The sequences were submitted to GenBank under accession nos MT946533 (DNA-A) and MT946534 (DNA-B). A phylogenetic tree for SLCMV and a link to the open SLCMV Nextstrain map (Hadfield et al., 2018) is included in Supplementary Figure 2. The sequences of the DNA-A and DNA-B components of the Champ1 isolate were nearly identical to those of anisolate of SLCMV from Ratanakiri, Cambodia (99.72% for DNA-A and 99.82 for DNA-B; Wang et al., 2016). Phylogenetic analysis (Supplementary Figure 2), grouped isolate Champ1 with those that form the cluster of SEA isolates that contain the shorter version of the rep gene (Siriwan et al., 2020). This short version of rep present a deletion of 7 amino acids at the C-terminus, which is involved in host responses to SLCMV (Wang et al., 2020). The confirmation of CMD and SLCMV in the border between Laos and Cambodia should be followed by disease containment and management strategies, particularly given that the majority cassava varieties grown in Laos are from neighbor countries, most of which have already reported the presence of CMD. Acknowledgements We thank all staff from the CIAT’s Cassava Program and the Plant Protection Center of Laos in Vientiane. We acknowledge financial support from the Australian Centre for International Agricultural Research (ACIAR) and the CGIAR Research Program on Roots, Tubers and Bananas (RTB) (https://www.cgiar.org/funders/).