Climate change is one of the main threats to biodiversity in the 21st century. However, the effects that it may have on different mammal species are unknown, making it difficult to implement ...conservation strategies. In this paper, we used species distribution models (SDM) to assess the effect of global climate change on the potential distribution of the 8 of the 9 marsupial species in Mexico, and analyzed their distribution in the current system of natural protected areas (NPAs). We used presence records for each species and bioclimatic variables from the present and the future (2050 and 2080) with 2 contrasting possible scenarios (representative concentration pathways RCP 4.5 and 8.5). We found that Tlacuatzin canescens would have the most stable potential range under any climate change scenario, while the remaining species (Caluromys derbianus, Chironectes minimus, Didelphis marsupialis, D. virginiana, Philander opossum, Marmosa mexicana, and Metachirus nudicaudatus) would undergo notable range losses in the future, though there would not only be losses—according to our SDMs, for all species there would be some range gain under the different climate scenarios, assuming the vegetation cover remained. The current system of NPAs in Mexico currently protects and under the 2 future scenarios would protect less than 20% of the potential range of marsupials, so a reevaluation of their areas beyond the NPAs is highly recommended for the long-term conservation of this group. Our results provide relevant information on the estimated effects of global climate change on marsupials, allowing us to design more effective methodologies for the protection of this portion of the mammalian fauna in Mexico. El cambio climático es una de las principales amenazas a la biodiversidad en el siglo XXI. Sin embargo, se desconocen los efectos que pueda tener sobre las diferentes especies de mamíferos, dificultando la implementación de estrategias para su conservación. En este estudio, empleamos Modelos de Distribución de Especies (SDM) para evaluar el efecto del cambio climático global sobre la distribución potencial de ocho de las nueve especies de marsupiales registradas en México, analizando además su distribución en el actual sistema de Áreas Naturales Protegidas (ANP). Utilizamos registros de presencia de cada especie y variables bioclimáticas del presente y del futuro (2050 y 2080) con dos escenarios contrastantes (RCP 4.5 y RCP 8.5). Encontramos que Tlacuatzin canescens mostrará el área de distribución potencial más estable ante cualquier escenario de cambio climático. Por el contrario, el resto de las especies (Caluromys derbianus, Chironectes minimus, Didelphis marsupialis, Didelphis virginiana, Philander opossum, Marmosa mexicana y Metachirus nudicaudatus) presentarán notables pérdidas de área de distribución en el futuro. Sin embargo, también encontramos que no sólo habrá pérdidas, ya que de acuerdo con nuestros SDM todas las especies mostrarán cierta ganancia de área de distribución bajo los diferentes escenarios climáticos, en el supuesto de que permanezca la cubierta vegetal. El actual sistema de ANP en México protege y, bajo los dos escenarios futuros, protegerá menos del 20% del área de distribución potencial de los marsupiales, por lo que es altamente recomendable reevaluar sus áreas de extensión para la conservación de este grupo a largo plazo. Nuestros resultados proporcionan información relevante de los efectos probables del cambio climático sobre los marsupiales, lo que permite generar metodologías más efectivas para la protección de los mamíferos en México.
Leptin is a hormone secreted mainly by adipocytes; physiologically, it participates in the control of appetite and energy expenditure. However, it has also been linked to tumor progression in ...different epithelial cancers. In this review, we describe the effect of leptin on epithelial-mesenchymal transition (EMT) markers in different study models, including in vitro, in vivo, and patient studies and in various types of cancer, including breast, prostate, lung, and ovarian cancer. The different studies report that leptin promotes the expression of mesenchymal markers and a decrease in epithelial markers, in addition to promoting EMT-related processes such as cell migration and invasion and poor prognosis in patients with cancer. Finally, we report that leptin has the greatest biological relevance in EMT and tumor progression in breast, lung, prostate, esophageal, and ovarian cancer. This relationship could be due to the key role played by the enriched tumor microenvironment in adipose tissue. Together, these findings demonstrate that leptin is a key biomolecule that drives EMT and metastasis in cancer.
To determine whether elevated intra-abdominal pressure (IAP) is associated with a higher rate of enteral nutrition-related gastrointestinal (GI) complications; to assess the value of IAP as a ...predictor of enteral nutrition (EN) intolerance. Intensive Care Unit (ICU) patients on mechanical ventilation requiring at least 5 days of EN were recruited for a prospective, observational, non-interventional, multicenter study. EN was performed and GI complications were managed with an established protocol. IAP was determined via a urinary catheter. Patients who developed any GI complications were considered as presenting EN intolerance. Variables related to EN, IAP and GI complications were monitored daily. Statistical analysis compared patients without GI complications (group A) vs. GI complications (group B). 247 patients were recruited from 28 participating ICUs (group A: 119, group B: 128). No differences between groups were recorded. Patients in group B (
< 0.001) spent more days on EN (8.1 ± 8.4 vs. 18.1 ± 13.7), on mechanical ventilation (8.0 ± 7.7 vs. 19.3 ± 14.9) and in the ICU (12.3 ± 11.4 vs. 24.8 ± 17.5). IAP prior to the GI complication was (14.3 ± 3.1 vs. 15.8 ± 4.8) (
< 0.003). The best IAP value identified for EN intolerance was 14 mmHg but it had low sensitivity and specificity. Although a higher IAP was associated with EN intolerance, IAP alone did not emerge as a good predictor of EN intolerance in critically ill patients.
The thermic effect of food (TEF) refers to the increase of the metabolic rate and body temperature in response to a single meal. To date, most of the studies have focused to determine the TEF in ...terms of energy expenditure, but little is known about which is the response in terms of skin temperature. The aim of this study was to analyze whether the thermic effect of food (TEF) on the skin temperature with a standardized and individualized liquid meal test is different in young adult men than in young adult women.
A total of 104 young adults (36 men and 68 women, age: 18–25 years old) consumed a standardized and individualized liquid meal (energy intake: 50% of measured basal metabolic rate, 50% carbohydrates, 35% fat, 15% protein). The skin temperature was measured by means of 17 iButtons during 3 h and 20 min. The mean, proximal, distal, and supraclavicular skin temperature, as well as the peripheral gradient, were determined as a proxy of a peripheral vasoconstriction. The participants reported the thermal sensation of the whole body, clavicular, feet, and hands zones. The body composition was measured by dual X-ray absorptiometry.
The overall, mean, proximal, and supraclavicular skin temperature significantly increased after the meal intake (all P < 0.05 vs. the baseline temperature). There was a postprandial peripheral vasoconstriction right after the meal intake and over the first hour and a peripheral vasodilatation during the second and third hour. Women had a higher increase in all skin temperature parameters in comparison to men (all, P < 0.05), whereas there were no sex differences in the proximal skin temperature (P = 0.279). The pattern of thermal sensation was similar between sexes, but women always felt colder than men. All of the results persisted after adjusting the analyses for body composition or menstrual cycle.
A standardized and individualized liquid meal test increases the skin temperature in young adults, being the thermic effect higher in women than in men.
In-depth study of cell cycle proteins and human papillomavirus (HPV) genotyping can provide useful information about the malignant potential of precursor lesions of cervical carcinoma (CC). ...Immunostaining of cell cycle-related proteins (p16, cyclin D1, Ki-67, p53, and ProEx C) was evaluated using tissue microarrays, and HPV genotypes were identified in 144 cervical tissue specimens encompassing normal or benign epithelial lesions, low- and high-grade squamous intraepithelial lesions (LSIL and HSIL, respectively), and CC. In addition, 14 cases with atypical immature metaplasia (AIM) were included to compare their immunohistochemical features with those of well-established precursor lesions. Expression of p16, Ki-67, and ProEx C was most associated with the severity of dysplasia. Positive expression of p16, Ki-67, and ProEx C and negative expression of p53 seem to be related to HPV-16 infection. AIM cases show an immunohistochemical pattern more similar to LSIL than to HSIL. Immunohistochemical assessment of cell cycle proteins may help to distinguish normal and benign conditions of the cervix from precursor lesions of CC.
Mortar mixtures were prepared by partial replacement of Portland cement with 0%, 10%, and 15% of residual fly ash to determine the structural evolution and compressive strength at 3, 7, 14, and 28 ...days. Portlandite, calcite, ettringite, iron oxide, silicon oxide, and sillimanite were identified in the standard mortar, and, additionally, magnetite was identified in the mortar with 10% and 15% fly ash. X-ray diffraction peaks corresponding to portlandite and ettringite increased in intensity with increasing curing time as a result of the consolidation of mineral species. The SEM analysis revealed that the standard mortar contained mainly portlandite and ettringite at 28 days, while the samples with 10% and 15% fly ash contained particles of fly ash coated with portlandite and ettringite, particles with a smooth surface, and particles of fly ash with signs of attack on their surfaces. The sc increased when the age of the mortar and the substitution of Portland cement by fly ash was increased from 3 to 28 days and from 0 to 15%, respectively.
We aimed to assess the resistance rates of antimicrobial-resistant, in bacterial pathogens of epidemiological importance in 47 Mexican centers.
In this retrospective study, we included a stratified ...sample of 47 centers, covering 20 Mexican states. Selected isolates considered as potential causatives of disease collected over a 6-month period were included. Laboratories employed their usual methods to perform microbiological studies. The results were deposited into a database and analyzed with the WHONET 5.6 software.
In this 6-month study, a total of 22,943 strains were included. Regarding Gram-negatives, carbapenem resistance was detected in ≤ 3% in Escherichia coli, 12.5% in Klebsiella sp. and Enterobacter sp., and up to 40% in Pseudomonas aeruginosa; in the latter, the resistance rate for piperacillin-tazobactam (TZP) was as high as 19.1%. In Acinetobacter sp., resistance rates for cefepime, ciprofloxacin, meropenem, and TZP were higher than 50%. Regarding Gram-positives, methicillin resistance in Staphylococcus aureus (MRSA) was as high as 21.4%, and vancomycin (VAN) resistance reached up to 21% in Enterococcus faecium. Acinetobacter sp. presented the highest multidrug resistance (53%) followed by Klebsiella sp. (22.6%) and E. coli (19.4%).
The multidrug resistance of Acinetobacter sp., Klebsiella sp. and E. coli and the carbapenem resistance in specific groups of enterobacteria deserve special attention in Mexico. Vancomycin-resistant enterococci (VRE) and MRSA are common in our hospitals. Our results present valuable information for the implementation of measures to control drug resistance.
SUMMARY
Background
Mexican children are characterized by a high‐starch intake diet and high prevalence of obesity.
Objectives
To investigate the association of AMY1A/AMY2A copy numbers (CNs) and ...AMY1/AMY2 serum enzymatic activity with childhood obesity in up to 427 and 337 Mexican cases and controls.
Methods
Anthropometric and dietary starch intake data were collected. CN of AMY1A/AMY2A and AMY1/AMY2 serum enzymatic activity were determined using droplet digital PCR (ddPCR) and enzymatic colorimetry, respectively. An individual participant level data meta‐analysis of association between AMY1A CNVs and obesity was also performed.
Results
A positive association between AMY1A/AMY2A CNs and their corresponding AMY1/AMY2 serum enzyme activity was observed in children with normal weight and obesity. The serum enzyme activity of AMY1 and AMY2 was negatively associated with childhood obesity risk, and the association was restricted to kids eating medium/high amount of starch (Pinteraction = .004). While no association between AMY1A and AMY2A CNs and childhood obesity was observed in our sample, we confirmed a significant association between AMY1A CN and obesity in a meta‐analysis of 3100 Mexican children.
Conclusions
Our data suggest that genetically determined salivary and pancreatic amylase activity can increase/decrease the risk of obesity in Mexican children, this effect being blunted by a low‐starch diet.
Abstract
Context
Rare partial/complete loss-of-function mutations in the melanocortin-4 receptor (MC4R) gene are the most common cause of Mendelian obesity in European populations, but their ...contribution to obesity in the Mexican population is unclear.
Objective and Design
We investigated whether deleterious mutations in MC4R contribute to obesity in Mexican children and adults.
Results
We provide evidence that the MC4R p.Ile269Asn (rs79783591) mutation may have arisen in modern human populations from a founder event in native Mexicans. The MC4R Isoleucine 269 is perfectly conserved across 184 species, which suggests a critical role for the amino acid in MC4R activity. Four in silico tools (SIFT, PolyPhen-2, CADD, MutPred2) predicted a deleterious impact of the p.Ile269Asn substitution on MC4R function. The MC4R p.Ile269Asn mutation was associated with childhood (Ncontrols = 952, Ncases = 661, odds ratio (OR) = 3.06, 95% confidence interval (95%CI) 1.94–4.85) and adult obesity (Ncontrols = 1445, Ncases = 2,487, OR = 2.58, 95%CI 1.52–4.39). The frequency of the MC4R p.Ile269Asn mutation ranged from 0.52 to 0.59% and 1.53 to 1.59% in children and adults with normal weight and obesity, respectively. The MC4R p.Ile269Asn mutation co-segregated perfectly with obesity in 5 multigenerational Mexican pedigrees. While adults with obesity carrying the p.Ile269Asn mutation had higher BMI values than noncarriers, this trend was not observed in children. The MC4R p.Ile269Asn mutation accounted for a population attributable risk of 1.28% and 0.68% for childhood and adult obesity, respectively, in the Mexican population.
Conclusion
The MC4R p.Ile269Asn mutation may have emerged as a founder mutation in native Mexicans and is associated with childhood and adult obesity in the modern Mexican population.
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