Sociodemographic determinants and mortality of premature newborns in a medium and low-income population in Colombia, 2017-2019. / Factores determinantes sociodemográficos y de mortalidad en recién nacidos prematuros en población de medianos y bajos ingresos en Colombia, 2017-2019

Introduction: The birth of premature babies is a public health problem with a high impact on infant morbidity and mortality. About 40% of mortality in children under five years occurs in the first month of life. Objective: To identify the association between maternal sociodemographic factors, premature birth, and mortality in newborns under 37 weeks in Santiago de Cali, 2017-2019. Materials and methods: We conducted a descriptive, cross-sectional study. We evaluated the records of Cali's Municipal Public Health Office. We calculated the crude and adjusted odd ratios and confidence intervals (95%) using the logistic regression model, data processing in Stata 16, and georeferencing the cases in the QGIS software. Results: From 2017 to 2019, premature babies in Cali corresponded to 11% of births. Poor prenatal care increased 3.13 times the risk of being born before 32 weeks (adjusted OR = 3.13; 95% CI = 2.75 - 3.56) and 1.27 times among mothers from outside the city (adjusted OR = 1.27; 95% CI = 1.15-1.41). Mortality was 4.29 per 1,000 live births. The mortality risk in newborns weighing less than 1,000 g increased 3.42 times (OR = 3.42; 95% CI = 2.85-4.12), delivery by cesarean section in 1.46 (OR = 1.46; CI 95% = 1.14-1.87) and an Apgar score - five minutes after birth- lower than seven in 1.55 times (OR = 1.55; CI 95% = 1.23-1.96). Conclusions: We found that less than three prenatal controls, mothers living outside Cali, afro-ethnicity, and cesarean birth were associated with prematurity of less than 32 weeks. We obtained higher mortality in newborns weighing less than 1,000 g.

Introducción: El nacimiento de bebés prematuros es un problema de salud pública con gran impacto en la morbimortalidad infantil: cerca del 40 % de las muertes de niños menores de cinco años sucede en el primer mes de vida. Objetivos: Identificar la asociación entre los factores sociodemográficos maternos, el parto prematuro y la mortalidad en recién nacidos menores de 37 semanas en Santiago de Cali, 2017-2019. Materiales y métodos: Se hizo un estudio descriptivo transversal. Se evaluaron los registros de la Secretaría de Salud Pública Municipal de Cali. Se calcularon las razones de probabilidad y los intervalos de confianza (95 %) crudos y ajustados mediante el modelo de regresión logística, en tanto que los datos se procesaron en Stata 16 y los casos se georreferenciaron con el programa QGIS. Resultados: Entre el 2017 y el 2019, los nacimientos de bebés prematuros en Cali correspondieron al 11 %. El control prenatal deficiente aumentó 3,13 veces el riesgo de nacer con menos de 32 semanas (OR ajustado = 3,13; IC95% = 2,75-3,56) y, en madres de municipios fuera de la ciudad, 1,27 veces (OR ajustado = 1,27; IC95% = 1,15-1,41). La mortalidad fue de 4,29 por 1.000 nacidos vivos. Nacer con un peso menor de 1.000 g aumentó el riesgo de mortalidad en 3,42 veces (OR = 3,42; IC95% = 2,85-4,12) y, un puntaje Apgar menor de siete a los cinco minutos del nacimiento, en 1,55 veces (OR=1,55; IC95% = 1,23-1,96). Conclusiones: Se encontró que tener menos de tres controles prenatales, la procedencia de la madre fuera de Cali, ser afrodescendiente y el parto por cesárea, estaban asociados significativamente con la prematuridad de menos de 32 semanas. Hubo mayor mortalidad en los recién nacidos con menos de 1.000 gramos al nacer.

PI3K Promotes Basal Cell Carcinoma Growth Through Kinase-Induced p21 Degradation.

Basal cell carcinoma (BCC) is a locally invasive epithelial cancer that is primarily driven by the Hedgehog (HH) pathway. Advanced BCCs are a critical subset of BCCs that frequently acquire resistance to Smoothened (SMO) inhibitors and identifying pathways that bypass SMO could provide alternative treatments for patients with advanced or metastatic BCC. Here, we use a combination of RNA-sequencing analysis of advanced human BCC tumor-normal pairs and immunostaining of human and mouse BCC samples to identify a PI3K pathway expression signature in BCC. Pharmacological inhibition of PI3K activity in BCC cells significantly reduces cell proliferation and HH signaling. However, treatment of Ptch1fl/fl ; Gli1-CreERT2 mouse BCCs with the PI3K inhibitor BKM120 results in a reduction of tumor cell growth with no significant effect on HH signaling. Downstream PI3K components aPKC and Akt1 showed a reduction in active protein, whereas their substrate, cyclin-dependent kinase inhibitor p21, showed a concomitant increase in protein stability. Our results suggest that PI3K promotes BCC tumor growth by kinase-induced p21 degradation without altering HH signaling.

MTOR promotes basal cell carcinoma growth through atypical PKC.

Advanced basal cell carcinomas (BCCs) are driven by the Hedgehog (HH) pathway and often possess inherent resistance to SMO inhibitors. Identifying and targeting pathways that bypass SMO could provide alternative treatments for patients with advanced or metastatic BCC. Here, we use a combination of RNA-sequencing analysis of advanced human BCC tumor-normal pairs and immunostaining of human and mouse BCC samples to identify an MTOR expression signature in BCC. Pharmacological inhibition of MTOR activity in BCC cells significantly reduces cell proliferation without affecting HH signalling. Similarly, treatment of the Ptch1 fl/fl ; Gli1-CreERT2 mouse BCC tumor model with everolimus reduces tumor growth. aPKC, a downstream target of MTOR, shows reduced activity, suggesting that MTOR promotes tumor growth by activating aPKC and demonstrating that suppressing MTOR could be a promising target for BCC patients.

Population dynamics of an invasive bird parasite, Philornis downsi (Diptera: Muscidae), in the Galapagos Islands.

The invasive parasitic fly, Philornis downsi (Muscidae), is one of the greatest threats to the avifauna of the Galapagos Islands. The larvae of this fly feed on the blood and tissues of developing nestlings of at least 18 endemic and native birds. The aim of the current study was to investigate biotic and abiotic factors that may influence the population dynamics of this invasive parasite. To study the influence of vegetation zone and related climatic factors on fly numbers, a bi-weekly monitoring program using papaya-baited traps was carried out at a dry, lowland site and at a humid, highland site on Santa Cruz Island between 2012-2014. Female flies, a large proportion of which were inseminated and gravid, were collected throughout the year at both sites, indicating females were active during and between the bird breeding seasons. This is the first evidence that female flies are able to persist even when hosts are scarce. On the other hand, catch rates of male flies declined between bird breeding seasons. Overall, catch rates of P. downsi were higher in the drier, lowland habitat, which may be a consequence of host or resource availability. Time was a stronger predictor of adult fly numbers than climate, further suggesting that P. downsi does not appear to be limited by its environment, but rather by host availability. Seasonal catch rates suggested that populations in both habitats were continuous and multivoltine. Numbers of adult female flies appeared to be regulated chiefly by simple direct density dependence, and may be governed by availability of bird nests with nestlings. Nevertheless, confounding factors such as the existence of reservoir hosts that perpetuate fly populations and changes in behavior of P. downsi may increase the vulnerability of bird hosts that are already IUCN red-listed or in decline.

Interactions between the Avian Parasite, Philornis downsi (Diptera: Muscidae) and the Galapagos Flycatcher, Myiarchus magnirostris Gould (Passeriformes: Tyrannidae).

An incidental observation of the fly Philornis downsi parasitizing a Galapagos Flycatcher (Myiarchus magnirostris) nest has revealed new insights into the searching behavior and biology of this invasive fly parasite and its interactions with endemic landbirds in the Galapagos Islands. Observations suggest that P. downsi relies on olfactory cues, or olfactory cues combined with the activity of adult birds, to locate nests and that flies continue to visit nests when chicks are >3 d old. At least 200 eggs were laid by P. downsi in different parts of the nest and >40 early-instar larvae were found inside the head of one chick, with additional larvae found in the base of the nest. Parasitism was the likely cause of mortality of both chicks found in or near the nest. This description of P. downsi parasitizing chicks of M. magnirostris highlights the vulnerability of this endemic bird species to this invasive fly.