Determinants and drivers of young children's diets in Latin America and the Caribbean: Findings from a regional analysis.

The Latin America and Caribbean region exhibit some of the lowest undernutrition rates globally. Yet, disparities exist between and within countries and countries in the region increasingly face other pressing nutritional concerns, including overweight, micronutrient deficiencies and inadequate child feeding practices. This paper reports findings from a regional analysis to identify the determinants and drivers of children's diets, with a focus on the complementary feeding window between the age of 6-23 months. The analysis consists of a narrative review and descriptive data analysis, complemented with qualitative interviews with key informants in four countries: Guatemala, Paraguay, Peru and Uruguay. Findings indicate that poverty and inequality (disparities within countries by wealth and residence), unequal access to services, inadequate coverage of social programmes and lack of awareness on appropriate feeding practices are important drivers for inadequate diets. We conclude that countries in the region need to invest in policies to tackle overweight and micronutrient deficiencies in young children, considering inequalities between and within countries, enhance coverage of social protection programmes, improve coordination between sectors to improve children's diets and expand the coverage and intensity of awareness campaigns on feeding practices, using iterative programme designs.

Nontoxic, double-deletion-mutant rabies viral vectors for retrograde targeting of projection neurons.

Recombinant rabies viral vectors have proven useful for applications including retrograde targeting of projection neurons and monosynaptic tracing, but their cytotoxicity has limited their use to short-term experiments. Here we introduce a new class of double-deletion-mutant rabies viral vectors that left transduced cells alive and healthy indefinitely. Deletion of the viral polymerase gene abolished cytotoxicity and reduced transgene expression to trace levels but left vectors still able to retrogradely infect projection neurons and express recombinases, allowing downstream expression of other transgene products such as fluorophores and calcium indicators. The morphology of retrogradely targeted cells appeared unperturbed at 1 year postinjection. Whole-cell patch-clamp recordings showed no physiological abnormalities at 8 weeks. Longitudinal two-photon structural and functional imaging in vivo, tracking thousands of individual neurons for up to 4 months, showed that transduced neurons did not die but retained stable visual response properties even at the longest time points imaged.