The earliest maize from San Marcos Tehuacán is a partial domesticate with genomic evidence of inbreeding.

Pioneering archaeological expeditions lead by Richard MacNeish in the 1960s identified the valley of Tehuacán as an important center of early Mesoamerican agriculture, providing by far the widest collection of ancient crop remains, including maize. In 2012, a new exploration of San Marcos cave (Tehuacán, Mexico) yielded nonmanipulated maize specimens dating at a similar age of 5,300-4,970 calibrated y B.P. On the basis of shotgun sequencing and genomic comparisons to Balsas teosinte and modern maize, we show herein that the earliest maize from San Marcos cave was a partial domesticate diverging from the landraces and containing ancestral allelic variants that are absent from extant maize populations. Whereas some domestication loci, such as teosinte branched1 (tb1) and brittle endosperm2 (bt2), had already lost most of the nucleotide variability present in Balsas teosinte, others, such as teosinte glume architecture1 (tga1) and sugary1 (su1), conserved partial levels of nucleotide variability that are absent from extant maize. Genetic comparisons among three temporally convergent samples revealed that they were homozygous and identical by descent across their genome. Our results indicate that the earliest maize from San Marcos was already inbred, opening the possibility for Tehuacán maize cultivation evolving from reduced founder populations of isolated and perhaps self-pollinated individuals.

Pancreatitis aguda como primera manifestación de un carcinoma microcítico de pulmón / Metastasis-induced aAcute pancreatitis as the initial presentation of a small cell lung carcinoma

Las metástasis de cualquier origen son una causa muy infrecuente de pancreatitis aguda. Se presenta el caso de una paciente con un episodio de pancreatitis aguda como manifestación inicial de un carcinoma microcítico de pulmón metastásico. Es importante excluir la presencia de tumores malignos en aquellos casos de pancreatitis aguda sin agente etiológico claro para mejorar el pronóstico de estos pacientes. Se revisó la literatura al respecto.

Metastases of different any origin that induceare a rare cause of acute pancreatitis are not frequent. We report the case 5 of a patient with an acute pancreatitis episode as the initial manifestation of an extended small cell lung carcinoma. The exclusion of malignancy in cases of pancreatitis of unknown origin is clinically relevant to improve the prognosis of these patients. We review the A literature review on about this topic is also presented.

[An infrequent cause of iron-deficiency anemia: Ménétrier disease]. / Una causa infrecuente de anemia ferropénica: Enfermedad de Ménétrier.

Ménétrier disease is a rare condition of an unknown origin, with a wide spectrum of clinical signs and symptoms at presentation. Diagnosis is made through the combination of clinical, analytical, endoscopic and histological data. Surgery is the classical treatment. However, new medical approaches have emerged.