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Grasspea (Lathyrus sativus L.) is recognized as a highly drought-tolerant legume. However, excessive consumption of its seeds and green tissues causes neurolathyrism, a condition characterized by an irreversible paralysis of the legs induced by a neurotoxin amino acid called ß-N-oxalyl-L-α, ß- diaminopropionic acid (ß-ODAP). The present study investigated the effects of heat, and combined heat + drought during the reproductive phase on physiological and phenological parameters, yield-related factors, ODAP content, and seed protein of 24 genotypes representing 11 Lathyrus species under controlled conditions. Analysis of variance revealed a highly significant effect (p < 0.001) of stress treatments and genotypes for all the traits. In general, heat stress individually or in combination with drought expedited phenology, reduced relative leaf water content, stimulated proline synthesis, and influenced chlorophyll concentration; the effects were more severe under the combined heat + drought stress. ODAP content in seeds ranged from 0.06 to 0.30% under no-stress conditions. However, under heat stress, there was a significant increase of 33% in ODAP content, and under combined stress (heat + drought), the increase reached 83%. Crude protein content ranged from 15.64 to 28.67% among no stress plants and decreased significantly by 23% under heat stress and by 36% under combined stress. The findings of this study also indicated substantial reductions in growth and grain yield traits under both heat stress and combined heat + drought stress. Six accessions namely IG 66026, IG 65018, IG 65687, IG 118511, IG 64931, and IG65273 were identified as having the most favorable combination of yield, protein content, and seed ODAP levels across all conditions. ODAP content in these six accessions varied from 0.07 to 0.11% under no stress and remained at moderate levels during both heat stress (0.09-0.14%) and combined stress (0.11-0.17%). IG 66026 was identified as the most stable genotype under drought and heat stress conditions with high protein content, and low ODAP content. By identifying those promising accessions, our results have established a basis for forthcoming grasspea breeding initiatives while paving the way for future research exploration into the fundamental mechanisms driving ODAP variation in the presence of both heat and drought stress conditions.

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Under-utilised orphan crops hold the key to diversified and climate-resilient food systems. Here, we report on orphan crop genomics using the case of Lablab purpureus (L.) Sweet (lablab) - a legume native to Africa and cultivated throughout the tropics for food and forage. Our Africa-led plant genome collaboration produces a high-quality chromosome-scale assembly of the lablab genome. Our assembly highlights the genome organisation of the trypsin inhibitor genes - an important anti-nutritional factor in lablab. We also re-sequence cultivated and wild lablab accessions from Africa confirming two domestication events. Finally, we examine the genetic and phenotypic diversity in a comprehensive lablab germplasm collection and identify genomic loci underlying variation of important agronomic traits in lablab. The genomic data generated here provide a valuable resource for lablab improvement. Our inclusive collaborative approach also presents an example that can be explored by other researchers sequencing indigenous crops, particularly from low and middle-income countries (LMIC).

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Grass pea (Lathyrus sativus L.) is a rich source of protein cultivated as an insurance crop in Ethiopia, Eritrea, India, Bangladesh, and Nepal. Its resilience to both drought and flooding makes it a promising crop for ensuring food security in a changing climate. The lack of genetic resources and the crop's association with the disease neurolathyrism have limited the cultivation of grass pea. Here, we present an annotated, long read-based assembly of the 6.5 Gbp L. sativus genome. Using this genome sequence, we have elucidated the biosynthetic pathway leading to the formation of the neurotoxin, ß-L-oxalyl-2,3-diaminopropionic acid (ß-L-ODAP). The final reaction of the pathway depends on an interaction between L. sativus acyl-activating enzyme 3 (LsAAE3) and a BAHD-acyltransferase (LsBOS) that form a metabolon activated by CoA to produce ß-L-ODAP. This provides valuable insight into the best approaches for developing varieties which produce substantially less toxin.

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Crop losses caused by plant pathogens are a primary threat to stable food production. Stripe rust (Puccinia striiformis) is a fungal pathogen of cereal crops that causes significant, persistent yield loss. Stripe rust exhibits host species specificity, with lineages that have adapted to infect wheat and barley. While wheat stripe rust and barley stripe rust are commonly restricted to their corresponding hosts, the genes underlying this host specificity remain unknown. Here, we show that three resistance genes, Rps6, Rps7, and Rps8, contribute to immunity in barley to wheat stripe rust. Rps7 cosegregates with barley powdery mildew resistance at the Mla locus. Using transgenic complementation of different Mla alleles, we confirm allele-specific recognition of wheat stripe rust by Mla. Our results show that major resistance genes contribute to the host species specificity of wheat stripe rust on barley and that a shared genetic architecture underlies resistance to the adapted pathogen barley powdery mildew and non-adapted pathogen wheat stripe rust.

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BACKGROUND: Mobile money-a service enabling users to receive, store, and send electronic money using mobile phones-has been widely adopted across low- and middle-income economies to pay for a variety of services, including healthcare. However, evidence on its effects on healthcare access and health outcomes are scarce and the possible implications of using mobile money for financing and payment of maternal healthcare services-which generally require large one-time out-of-pocket payments-have not yet been systematically assessed in low-resource settings. The aim of this study is to determine the impact on health outcomes, cost-effectiveness, feasibility, acceptability, and usefulness of mobile phone-based savings and payment service, the Mobile Maternal Health Wallet (MMHW), for skilled healthcare during pregnancy and delivery among women in Madagascar. METHODS: This is a hybrid effectiveness-implementation type-1 trial, determining the effectiveness of the intervention while evaluating the context of its implementation in Madagascar's Analamanga region, containing the capital, Antananarivo. Using a stratified cluster randomized design, 61 public-sector primary-care health facilities were randomized within 6 strata to either receive the intervention or not (29 intervention vs. 32 control facilities). The strata were defined by a health facility's antenatal care visit volume and its capacity to offer facility-based deliveries. The registered pre-specified primary outcomes are (i) delivery at a health facility, (ii) antenatal care visits, and (iii) total healthcare expenditure during pregnancy, delivery, and neonatal period. The registered pre-specified secondary outcomes include additional health outcomes, economic outcomes, and measurements of user experience and satisfaction. Our estimated enrolment number is 4600 women, who completed their pregnancy between July 1, 2020, and December 31, 2021. A series of nested mixed-methods studies will elucidate client and provider perceptions on feasibility, acceptability, and usefulness of the intervention to inform future implementation efforts. DISCUSSION: A cluster-randomized, hybrid effectiveness-implementation design allows for a robust approach to determine whether the MMHW is a feasible and beneficial intervention in a resource-restricted public healthcare environment. We expect the results of our study to guide future initiatives and health policy decisions related to maternal and neonatal health and universal healthcare coverage through technology in Madagascar and other countries in sub-Saharan Africa. TRIAL REGISTRATION: This trial was registered on March 12, 2021: Deutsches Register Klinischer Studien (German Clinical Trials Register), identifier: DRKS00014928 . For World Health Organization Trial Registration Data Set see Additional file 1.

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BACKGROUND: Grass pea (Lathyrus sativus) is an underutilised crop with high tolerance to drought and flooding stress and potential for maintaining food and nutritional security in the face of climate change. The presence of the neurotoxin ß-L-oxalyl-2,3-diaminopropionic acid (ß-L-ODAP) in tissues of the plant has limited its adoption as a staple crop. To assist in the detection of material with very low neurotoxin toxin levels, we have developed two novel methods to assay ODAP. The first, a version of a widely used spectrophotometric assay, modified for increased throughput, permits rapid screening of large populations of germplasm for low toxin lines and the second is a novel, mass spectrometric procedure to detect very small quantities of ODAP for research purposes and characterisation of new varieties. RESULTS: A plate assay, based on an established spectrophotometric method enabling high-throughput ODAP measurements, is described. In addition, we describe a novel liquid chromatography mass spectrometry (LCMS)-based method for ß-L-ODAP-quantification. This method utilises an internal standard (di-13C-labelled ß-L-ODAP) allowing accurate quantification of ß-L-ODAP in grass pea tissue samples. The synthesis of this standard is also described. The two methods are compared; the spectrophotometric assay lacked sensitivity and detected ODAP-like absorbance in chickpea and pea whereas the LCMS method did not detect any ß-L-ODAP in these species. The LCMS method was also used to quantify ß-L-ODAP accurately in different tissues of grass pea. CONCLUSIONS: The plate-based spectrophotometric assay allows quantification of total ODAP in large numbers of samples, but its low sensitivity and inability to differentiate α- and ß-L-ODAP limit its usefulness for accurate quantification in low-ODAP samples. Coupled to the use of a stable isotope internal standard with LCMS that allows accurate quantification of ß-L-ODAP in grass pea samples with high sensitivity, these methods permit the identification and characterisation of grass pea lines with a very low ODAP content. The LCMS method is offered as a new 'gold standard' for ß-L-ODAP quantification, especially for the validation of existing and novel low- and/or zero-ß-L-ODAP genotypes.

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[This corrects the article DOI: 10.2196/11420.].

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BACKGROUND: Mobile savings and payment systems have been widely adopted to store money and pay for a variety of services, including health care. However, the possible implications of these technologies on financing and payment for maternal health care services-which commonly require large 1-time out-of-pocket payments-have not yet been systematically assessed in low-resource settings. OBJECTIVE: The aim of this study was to determine the structural, contextual, and experiential characteristics of a mobile phone-based savings and payment platform, the Mobile Health Wallet (MHW), for skilled health care during pregnancy among women in Madagascar. METHODS: We used a 2-stage cluster random sampling scheme to select a representative sample of women utilizing either routine antenatal (ANC) or routine postnatal care (PNC) in public sector health facilities in 2 of 8 urban and peri-urban districts of Antananarivo, Madagascar (Atsimondrano and Renivohitra districts). In a quantitative structured survey among 412 randomly selected women attending ANC or PNC, we identified saving habits, mobile phone use, media consumptions, and perception of an MHW with both savings and payment functions. To confirm and explain the quantitative results, we used qualitative data from 6 semistructured focus group discussions (24 participants in total) in the same population. RESULTS: 59.3% (243/410, 95% CI 54.5-64.1) saved toward the expected costs of delivery and, out of those, 64.4% (159/247, 95% CI 58.6-70.2) used household cash savings for this purpose. A total of 80.3% (331/412, 95% CI 76.5-84.1) had access to a personal or family phone and 35.7% (147/412, 95% CI 31.1-40.3) previously used Mobile Money services. Access to skilled health care during pregnancy was primarily limited because of financial obstacles such as saving difficulties or unpredictability of costs. Another key barrier was the lack of information about health benefits or availability of services. The general concept of an MHW for saving toward and payment of pregnancy-related care, including the restriction of payments, was perceived as beneficial and practicable by the majority of participants. In the discussions, several themes pointed to opportunities for ensuring the success of an MHW through design features: (1) intuitive technical ease of use, (2) clear communication and information about benefits and restrictions, and (3) availability of personal customer support. CONCLUSIONS: Financial obstacles are a major cause of limited access to skilled maternal health care in Madagascar. An MHW for skilled health care during pregnancy was perceived as a useful and desirable tool to reduce financial barriers among women in urban Madagascar. The design of this tool and the communication strategy will likely be the key to success. Particularly important dimensions of design include technical user friendliness and accessible and personal customer service.

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BACKGROUND: Modelling genetic phenomena affecting biological traits is important for the development of agriculture as it allows breeders to predict the potential of breeding for certain traits. One such phenomenon is heterosis or hybrid vigor: crossing individuals from genetically distinct populations often results in improvements in quantitative traits, such as growth rate, biomass production and stress resistance. Heterosis has become a very useful tool in global agriculture, but its genetic basis remains controversial and its effects hard to predict. We have taken a computational approach to studying heterosis, developing a simulation of evolution, independent reassortment of alleles and hybridization of Gene Regulatory Networks (GRNs) in a Boolean framework. These artificial regulatory networks exhibit topological properties that reflect those observed in biology, and fitness is measured as the ability of a network to respond to external inputs in a pre-defined way. RESULTS: Our model reproduced common experimental observations on heterosis using only biologically justified parameters, such as mutation rates. Hybrid vigor was observed and its extent was seen to increase as parental populations diverged, up until a point of sudden collapse of hybrid fitness. Thus, the model also describes a process akin to speciation due to genetic incompatibility of the separated populations. We also reproduce, for the first time in a model, the fact that hybrid vigor cannot easily be fixed by within a breeding line, currently an important limitation of the use of hybrid crops. The simulation allowed us to study the effects of three standard models for the genetic basis of heterosis: dominance, over-dominance, and epistasis. CONCLUSION: This study describes the most detailed simulation of heterosis using gene regulatory networks to date and reproduces several phenomena associated with heterosis for the first time in a model. The level of detail in our model allows us to suggest possible warning signs of the impending collapse of hybrid vigor in breeding. In addition, the simulation provides a framework that can be extended to study other aspects of heterosis and alternative evolutionary scenarios.

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Cold thyroid nodules (CTNs) are characterized by a reduced iodide uptake in comparison to normal thyroid tissue. The sodium iodide symporter (NIS) is the first step in thyroid hormone synthesis and mediates the active iodide transport in the thyroid cells suggesting that decreased iodide uptake could be a result of changes in NIS expression or molecular defects in the NIS gene. In contrast to previous studies, an intraindividual comparison of NIS mRNA expression in CTNs and their corresponding surrounding tissue was performed using direct detection of NIS mRNA. A significant reduction in NIS mRNA expression was detected in 86% of the 14 investigated CTNs. We hypothesized that human sodium iodide symporter (hNIS) transcriptional failure could be caused by primary molecular NIS gene defects and/or methylation of DNA in the NIS promoter. However, no mutation in the NIS cDNA nor in the NIS promoter region upstream up to-443 bp from the ATG start codon was detected. Therefore, primary molecular NIS gene defects were excluded. However, in 50% of CTNs with reduced NIS mRNA expression, the promoter region was hypermethylated. NIS mRNA expression in these hypermethylated CTNs only reached a maximum of 30% of the corresponding surrounding tissue. Hence, methylation of CpG islands in the NIS promotor could be a regulatory mechanism of NIS transcription in CTNs. Immunoblot revealed absent hNIS protein expression in the total cell membrane fraction in 45% of investigated nodules. In the majority of the remaining CTNs NIS protein expression was decreased in the nodule tissue compared to the corresponding surrounding tissue. For investigating protein expression immunhistochemistry has two advantages. First, the whole nodule area can be investigated, and second, NIS expression can be detected in areas where an immunoblot of a cell membrane fraction is negative. Interestingly, immunhistochemistry revealed higher NIS expression in 50% of CTNs compared to their corresponding surrounding tissues and NIS staining was predominantly intracellular. These data demonstrate that NIS protein expression does not reflect NIS mRNA expression. Therefore, factors that affect targeting of NIS to the plasma membrane are likely to be affected.

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Thyroid follicular adenomas and adenomatous thyroid nodules are a frequent finding in geographical areas with iodine deficiency. They occur as hypofunctioning (scintigraphically cold) or hyperfunctioning (scintigraphically hot) nodules. Their predominant clonal origin suggests that they result from clonal expansion of a single cell, which is very likely the result of a prolonged increase in proliferation compared with non-affected surrounding cells. To test whether increased cell proliferation is detectable in cold thyroid nodules, we studied paraffin-embedded tissue from 40 cold thyroid nodules and their surrounding normal thyroid tissue for the occurrence of the proliferating cell nuclear antigen (PCNA) and Ki-67 (MIB-1 antibody) epitopes as markers for cell proliferation. All 40 thyroid nodules were histologically well characterized and have been studied for molecular characteristics before. The labeling index (number of labeled cells versus total cell number) for nodular and surrounding tissue was calculated. In 33 cold thyroid nodules a significant (p < or = 0.05) increase in the labeling index for PCNA was detectable. In 19 cold thyroid nodules a significant (p < or = 0.05) increase in the labeling index for Ki-67 was detectable. Moreover, surrounding tissues with lymphocyte infiltration showed a significantly higher labeling index for both PCNA and Ki-67 compared with normal surrounding tissue. These findings are first evidence that an increased thyroid epithelial cell proliferation is a uniform feature common to most cold nodules. However, the increase of proliferation markers shows a heterogeneity that is not correlated with histopathologic, molecular, or clinical characteristics.

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