Revisión histórica, distribución potencial y estado de conservación de la rata endémica de México Xenomys nelsoni (Rodentia: Cricetidae) / Historical review, potential distribution, and conservation of the Mexican endemic rat Xenomys nelsoni (Rodentia: Cricetidae)

Resumen Introducción: La Rata de Magdalena, Xenomys nelsoni, es un roedor endémico de México, de distribución restringida a las selvas bajas caducifolias densas, en una pequeña región de la costa del Pacífico mexicano. Es una especie poco conocida, catalogada como "En Peligro" de acuerdo con la Unión Internacional para la Conservación de la Naturaleza (IUCN). Este desconocimiento unido a la alta tasa de deforestación de su hábitat hace que su conservación sea prioritaria. Objetivo: Realizar un recuento histórico de los registros depositados en las colecciones científicas, generar mapas de distribución potencial y analizar el estado de conservación de la especie. Método: Los datos de ocurrencia de las especies se obtuvieron de la literatura y bases de datos digitales y se analizaron por décadas. Se utilizaron los programas GARP y MaxEnt para generar los modelos de nicho ecológico. La importancia de las variables en el modelo se estimó mediante un análisis Jackknife. Resultados: A lo largo de 129 años 19 recolectores registraron 69 ejemplares, de los cuales 65 están depositados en siete colecciones internacionales y una nacional. Aunque la especie sólo se ha recolectado en Jalisco y Colima, la distribución potencial de X. nelsoni incluye también el estado de Michoacán. De esta área estimada, sólo el 1.5 % se encuentra dentro de un Área Natural Protegida. Conclusiones: Los resultados de la distribución potencial podrían ser utilizados para verificar la presencia de la especie en lugares donde no ha sido recolectada como el norte de la Reserva de la Biosfera Chamela-Cuixmala y en algunas zonas de la provincia fisiográfica Costas del Sur en el estado de Michoacán. Es necesario incrementar los muestreos en regiones poco estudiadas predichas por el modelo y aumentar el área de protección.

Abstract Introduction: The Magdalena Rat, Xenomys nelsoni, is a rodent endemic to Mexico, whose distribution is restricted to dense tropical dry forests in a small region on the Pacific coast of Mexico. It is a poorly known species categorized as "Endangered" by the International Union for Conservation of Nature (IUCN). This lack of knowledge and the high rates of deforestation of its habitat makes its conservation a priority. Objective: To summarize the historical records deposited in scientific collections, to create potential distribution maps, and to analyze the conservation status of the species. Methods: We obtained species occurrence data from literature and digital databases, analyzing them by the decade. We used GARP and MaxEnt software to generate the ecological niche models. The importance of the variables in the model was estimated using the Jackknife technique. Results: Over 129 years, 19 collectors registered 69 specimens, of which 65 are deposited in one national and seven international collections. Although the species has only been collected in Jalisco and Colima, the potential distribution for X. nelsoni also includes the state of Michoacán. Of this estimated area, only 1.5 % is in a Protected Natural Area. Conclusions: The results of the potential distribution could be used to verify the presence of the species in places where it has not been collected, such as the northern part of the Chamela-Cuixmala Biosphere Reserve and in some areas of the physiographic province Costas del Sur in the state of Michoacán. It is needed to increase samplings in the least studied regions predicted by the model and expand the area of protection.

Molnupiravir for Oral Treatment of Covid-19 in Nonhospitalized Patients.

BACKGROUND: New treatments are needed to reduce the risk of progression of coronavirus disease 2019 (Covid-19). Molnupiravir is an oral, small-molecule antiviral prodrug that is active against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). METHODS: We conducted a phase 3, double-blind, randomized, placebo-controlled trial to evaluate the efficacy and safety of treatment with molnupiravir started within 5 days after the onset of signs or symptoms in nonhospitalized, unvaccinated adults with mild-to-moderate, laboratory-confirmed Covid-19 and at least one risk factor for severe Covid-19 illness. Participants in the trial were randomly assigned to receive 800 mg of molnupiravir or placebo twice daily for 5 days. The primary efficacy end point was the incidence hospitalization or death at day 29; the incidence of adverse events was the primary safety end point. A planned interim analysis was performed when 50% of 1550 participants (target enrollment) had been followed through day 29. RESULTS: A total of 1433 participants underwent randomization; 716 were assigned to receive molnupiravir and 717 to receive placebo. With the exception of an imbalance in sex, baseline characteristics were similar in the two groups. The superiority of molnupiravir was demonstrated at the interim analysis; the risk of hospitalization for any cause or death through day 29 was lower with molnupiravir (28 of 385 participants [7.3%]) than with placebo (53 of 377 [14.1%]) (difference, -6.8 percentage points; 95% confidence interval [CI], -11.3 to -2.4; P = 0.001). In the analysis of all participants who had undergone randomization, the percentage of participants who were hospitalized or died through day 29 was lower in the molnupiravir group than in the placebo group (6.8% [48 of 709] vs. 9.7% [68 of 699]; difference, -3.0 percentage points; 95% CI, -5.9 to -0.1). Results of subgroup analyses were largely consistent with these overall results; in some subgroups, such as patients with evidence of previous SARS-CoV-2 infection, those with low baseline viral load, and those with diabetes, the point estimate for the difference favored placebo. One death was reported in the molnupiravir group and 9 were reported in the placebo group through day 29. Adverse events were reported in 216 of 710 participants (30.4%) in the molnupiravir group and 231 of 701 (33.0%) in the placebo group. CONCLUSIONS: Early treatment with molnupiravir reduced the risk of hospitalization or death in at-risk, unvaccinated adults with Covid-19. (Funded by Merck Sharp and Dohme; MOVe-OUT ClinicalTrials.gov number, NCT04575597.).

A Case Study of Ring Chromosome 13 in a Pediatric Patient.

OBJECTIVES: Ring chromosomes, which are formed through the fusion of the telomeric ends of a chromosome, present with a spectrum of symptoms whose severity depends on the amount of genetic material lost. Ring chromosome 13 cases present with symptoms similar to that of deletion 13q syndrome, and can be classified depending on whether several critical regions are involved in the deletion. An important region to consider is locus 13q32, whose deletion is known to cause severe phenotypes and major malformations. In contrast, deletions of the more distal locus 13q34 have been shown to be involved in symptoms such as microcephaly and ambiguous genitalia. Herein, we report a case of a pediatric patient with r(13) who presented with microcephaly, facial dysmorphism, hand and feet anomalies, and ambiguous genitalia. The karyotype was described as 46,XY,r(13)(p11.1q34). This case highlights the importance of cytogenetic analysis in determining the prognostic implications of ring chromosome cases.

Competencias transversales en la formación de los profesionales médicos. Una revisión / Cross-cutting Competencies in Medical Professional Training. A Review / Competências transversais na formação de profissionais médicos. Uma revisão

El presente artículo discute el proceso de formación del profesional médico en Colombia y sus posibles estrategias de enseñanza y tiene como fin problematizar el documento de política pública Perfiles y competencias profesionales de la salud, elaborado por el Ministerio de Salud y Protección Social y la Academia Nacional de Medicina a través de la selección de las competencias que correspondían con la relación social y la comunicación, propias de la atención médica: reconocimiento del contexto y relaciones interpersonales. Para esto se hizo una revisión documental a través de la búsqueda, selección y análisis de artículos académicos que trabajaran las posibles estrategias de enseñanza de las competencias mencionadas. Como conclusiones destacan la reflexión permanente que se ha hecho sobre el tema, así como la urgencia de trascender de la formación biológica hacia una formación más integral; no obstante, son pocas las reflexiones que concretan propuestas específicas de cómo lograrlo. De igual manera, existe un vacío sobre la definición y los alcances del concepto de integralidad y una falta de consenso en la forma de llamar aquellas competencias que le apuntan a esta.

This article discusses the process of training medical professionals in Colombia and their possible teaching strategies. Besides, it sought to problematize the public policy document "Profiles and Professional Competencies of Health" (Prepared by the Ministry of Health and Social Protection and the National Academy of Medicine) through the selection of competencies that corresponded to the social relationship and communication that constitute medical care: Recognition of Context and Interpersonal Relationships. For this purpose, a documentary review was done through the search, selection, and analysis of academic articles that worked on the possible teaching strategies for the mentioned competences. Among the conclusions, it stands out the permanent reflection that has been done on the subject, as well as the urgency of transcending biological formation towards a more integral formation. However, a few reflections define specific proposals on how to achieve it. Likewise, there is a gap in the definition and scope of the integrality concept or even a consensus about de definitions and concepts that those competences reach out.

Este artigo discute o processo de formação profissional médico na Colômbia e suas possíveis estratégias de ensino e tem como objetivo problematizar o documento de política pública Perfis e competências profissionais em saúde, elaborado pelo Ministério da Saúde e Proteção Social e pela Academia Nacional da Medicina através da seleção das competências que correspondem à relação social e à comunicação, próprias da assistência médica: reconhecimento do contexto e relações interpessoais. Para tanto, foi realizada uma revisão documental por meio da busca, seleção e análise de artigos acadêmicos que trabalharam as possíveis estratégias de ensino das referidas competências. Como conclusões destacam-se a reflexão permanente que se tem feito sobre o assunto, bem como a urgência de transcender a formação biológica para uma formação mais integral; no entanto, poucas reflexões fazem propostas específicas sobre como alcançá-lo. Da mesma forma, há um vazio na definição e abrangência do conceito de integralidade e uma falta de consenso na forma de denominar as competências que apontam para ele

Early Life Exposure to Fructose Alters Maternal, Fetal and Neonatal Hepatic Gene Expression and Leads to Sex-Dependent Changes in Lipid Metabolism in Rat Offspring.

AIM: Fructose consumption is associated with altered hepatic function and metabolic compromise and not surprisingly has become a focus for perinatal studies. We have previously shown that maternal fructose intake results in sex specific changes in fetal, placental and neonatal outcomes. In this follow-up study we investigated effects on maternal, fetal and neonatal hepatic fatty acid metabolism and immune modulation. METHODS: Pregnant rats were randomised to either control (CON) or high-fructose (FR) diets. Fructose was given in solution and comprised 20% of total caloric intake. Blood and liver samples were collected at embryonic day 21 (E21) and postnatal day (P)10. Maternal liver samples were also collected at E21 and P10. Liver triglyceride and glycogen content was measured with standard assays. Hepatic gene expression was measured with qPCR. RESULTS: Maternal fructose intake during pregnancy resulted in maternal hepatic ER stress, hepatocellular injury and increased levels of genes that favour lipogenesis. These changes were associated with a reduction in the NLRP3 inflammasome. Fetuses of mothers fed a high fructose diet displayed increased hepatic fructose transporter and reduced fructokinase mRNA levels and by 10 days of postnatal age, also have hepatic ER stress, and elevated IL1ß mRNA levels. At P10, FR neonates demonstrated increased hepatic triglyceride content and particularly in males, associated changes in the expression of genes regulating beta oxidation and the NLRP3 inflammasome. Further, prenatal fructose results in sex-dependant changes in levels of key clock genes. CONCLUSIONS: Maternal fructose intake results in age and sex-specific alterations in maternal fetal and neonatal free fatty acid metabolism, which may be associated in disruptions in core clock gene machinery. How these changes are associated with hepatic inflammatory processes is still unclear, although suppression of the hepatic inflammasome, as least in mothers and male neonates may point to impaired immune sensing.

Early life exposure to undernutrition induces ER stress, apoptosis, and reduced vascularization in ovaries of adult rat offspring.

Maternal nutritional restriction has been shown to induce impairments in a number of organ systems including the ovary. We have previously shown that maternal undernutrition induces fetal growth restriction and low birth weight, and results in an offspring ovarian phenotype characteristic of premature ovarian aging with reduced ovarian reserve. In the present study, we set out to investigate the underlying mechanisms that lead offspring of undernourished mothers to premature ovarian aging. Pregnant dams were randomized to 1) a standard diet throughout pregnancy and lactation (control), 2) a calorie-restricted (50% of control) diet during pregnancy, 3) a calorie-restricted (50% of control) diet during pregnancy and lactation, or 4) a calorie-restricted (50% of control) diet during lactation alone. The present study shows that early life undernutrition-induced reduction of adult ovarian follicles may be mediated by increased ovarian endoplasmic reticulum stress in a manner that increased follicular apoptosis but not autophagy. These changes were associated with a loss of ovarian vessel density and are consistent with an accelerated ovarian aging phenotype. Whether these changes are mediated specifically by a reduction in the local antioxidant environment is unclear, although our data suggest the possibility that ovarian melatonin may play a part in early life nutritional undernutrition and impaired offspring folliculogenesis.

Organochlorine pesticide exposure among agricultural workers in Colombian regions with illegal crops: an exploration in a hidden and dangerous world.

A previous study suggested that banned organochlorine pesticides were being used to protect illegal crops from pests. The study herein explored the exposure of individuals living in a region with such crops. Samples from 99 individuals were collected during 2005 and 2006 and organochlorine pesticides were quantified using chromatography in serum samples. We detected heptachlor (72.73%), 4,4-DDE (19.19%), aldrin (15.15%), γ-chlordane (12.12%), dieldrin (11.11%), α-chlordane (10,10%), α-endosulfan (8.08%), endosulfan (6.06%), ß-endosulfan (5.05%), oxychlordane (3.03%), 4,4-DDT (3.03%), and 2,4-DDT (2.02%). Heptachlor had a skewed and negative distribution (median: 8.69 ng/l and maximum: 43.8 ng/l). A two-dimensional biplot suggested that mixtures present were endosulfan/4,4-DDT, aldrin/γ-chlordane, and oxychlordane/ß-endosulfan/dieldrin. We did not identify variables associated with exposure levels. These data suggest that banned organochlorine pesticides are used. This is an example of research in a war context, where the problems related with pesticides are complex, and their implications go beyond a toxicological or epidemiological viewpoint.

Maternal undernutrition significantly impacts ovarian follicle number and increases ovarian oxidative stress in adult rat offspring.

BACKGROUND: We have shown recently that maternal undernutrition (UN) advanced female pubertal onset in a manner that is dependent upon the timing of UN. The long-term consequence of this accelerated puberty on ovarian function is unknown. Recent findings suggest that oxidative stress may be one mechanism whereby early life events impact on later physiological functioning. Therefore, using an established rodent model of maternal UN at critical windows of development, we examined maternal UN-induced changes in offspring ovarian function and determined whether these changes were underpinned by ovarian oxidative stress. METHODOLOGY/PRINCIPAL FINDINGS: Our study is the first to show that maternal UN significantly reduced primordial and secondary follicle number in offspring in a manner that was dependent upon the timing of maternal UN. Specifically, a reduction in these early stage follicles was observed in offspring born to mothers undernourished throughout both pregnancy and lactation. Additionally, antral follicle number was reduced in offspring born to all mothers that were UN regardless of whether the period of UN was restricted to pregnancy or lactation or both. These reductions were associated with decreased mRNA levels of genes critical for follicle maturation and ovulation. Increased ovarian protein carbonyls were observed in offspring born to mothers UN during pregnancy and/or lactation and this was associated with peroxiredoxin 3 hyperoxidation and reduced mRNA levels; suggesting compromised antioxidant defence. This was not observed in offspring of mothers UN during lactation alone. CONCLUSIONS: We propose that maternal UN, particularly at a time-point that includes pregnancy, results in reduced offspring ovarian follicle numbers and mRNA levels of regulatory genes and may be mediated by increased ovarian oxidative stress coupled with a decreased ability to repair the resultant oxidative damage. Together these data are suggestive of maternal UN potentially contributing to premature ovarian ageing in offspring.

Crop and non-crop productivity in a traditional maize agroecosystem of the highland of Mexico.

BACKGROUND: In Mexico, the traditional maize cultivation system has resisted intensification attempts for many decades in some areas, even in some well-connected regions of the temperate highlands. We suggest that this is due to economics. METHODS: The total useful biomass of several fields in Nanacamilpa, Tlaxcala, are evaluated for productivity and costs. RESULTS: Maize grain production is low (1.5 t ha(-1)) and does not cover costs. However, maize stover demands a relatively high price. If it included, a profit is possible (about 110 US $ ha(-1)). We show that non-crop production (weeds for food and forage) potentially has a higher value than the crop. It is only partially used, as there are constraints on animal husbandry, but it diversifies production and plays a role as a back-up system in case of crop failure. CONCLUSION: The diversified system described is economically rational under current conditions and labor costs. It is also stable, low-input and ecologically benign, and should be recognized as an important example of integrated agriculture, though some improvements could be investigated.