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Estudios realizados en la región latinoamericana (SERCE 2006, TERCE 2013), demostraron el bajo nivel de dominio de los estudiantes de educación primaria panameña en asignaturas básicas, entre ellas matemática. Con este antecedente el presente estudio se focalizó en los contenidos de aprendizaje relacionados con las operaciones de aritméticas fundamentales con números naturales y específicamente en sexto grado de educación primaria de las escuelas Tomás Herrera e Hipólito Pérez Tello de la ciudad de Chitré. Esta investigación fue de tipo exploratoria para analizar las dificultades que presentaban los estudiantes y se encontró que ellos no alcanzaron logros en el dominio necesario, a pesar de que el currículo oficial prescribe que dichos aprendizajes deben adquirirse en los primeros años de educación primaria. Se utilizó la prueba Z Normal para contrastar la hipótesis de trabajo. Con esta prueba se obtuvo el rechazo de la hipótesis nula, aceptando la alternativa y la cual asegura que las notas obtenidas por los estudiantes es menor que 3,0, a un nivel de significación del 5%.

The cheese known as Momposino is a Colombian variety of pasta filata cheese. For this investigation, several cheese-production technologies were identified as follows: techniques 1 and 2, for cheeses elaborated from raw milk (such as autochthonous cheeses): technique 3, for cheeses made with pasteurized milk and with a culture; and technique 4, for cheeses made with raw milk. Volatile compounds and free amino acids were examined through chromatography and sensory evaluation tests performed by the members of laboratory. Cheeses made with techniques 1 and 2 presented more volatile compounds (with 60 and 73 respectively) than the cheeses made with technique 3 (for which 52 volatile compounds were found), and the ones made with technique 4 (which presented 40 volatile compounds). The fat content for cheeses from Technique 1 was 29.8%, 30% for cheeses from Technique 2, 27% for cheeses from Technique 3, and 25% for the ones made with Technique 4. These results lead to conclude that the higher the fat content is, the higher the volatile compound production will be. The volatile profiles that were found include acids, alcohols, hydrocarbons and esters. Through the Thin Layer Chrograthography test, it was found that cheese proteins spread to the following amino acids: arginine, valine, tryptophan, histidine, threonine, lysine, tyrosine, alanine, and cysteine. In the cheeses from all treatments, the most outstanding flavor was the acid flavor, and in the most outstanding texture was the elastic texture. No significant differences were found in the sensory evaluation, for the free amino acids (p>0.05), but free fatty acids and fat did show significant differences (pEl queso Momposino es una variedad de queso de pasta hilada que se encuentra comúnmente en Colombia. Para esta investigación fueron identificadas varias tecnologías de producción de queso de la siguiente manera: técnicas 1 y 2, para quesos elaborados de leche cruda (tales como quesos autóctonos), técnica 3, para quesos hechos con leche pasteurizada y con un cultivo; y técnica 4, para quesos hechos con leche cruda. Los compuestos volátiles y aminoácidos libres fueron examinados por cromatografía y la evaluación sensorial desempeñada por los miembros del laboratorio. Los quesos hechos con las técnicas 1 y 2 presentaron más compuestos volátiles (con 60 y 73 respectivamente) que los quesos hechos con la técnica 3 (para el cual 52 compuestos volátiles fueron encontrados), y los hechos con la técnica 4 (el cual presentó 40 compuestos volátiles). El contenido de grasa para la técnica 1 fue 29,8%, 30% para quesos de la técnica 2, 27% para quesos de la técnica 3, y 25% para los hechos con la técnica 4. Estos resultados llevan a concluir que en el más alto contenido de grasa será la más alta producción de compuestos volátiles. Los perfiles volátiles que fueron encontrados incluyen ácidos, alcoholes, hidrocarburos y ésteres. Por la prueba de Cromatografía en Capa Fina, se encontró que las proteínas de los quesos se dividían en los siguientes aminoácidos: arginina, valina, triptófano, histidina, treonina, lisina, tirosina, alanina y cisteína. En todos los tratamientos de los quesos, el sabor más destacado fue el sabor ácido, y la textura más destacada fue la textura elástica. No fueron encontradas diferencias significativas en la evaluación sensorial, para los aminoácidos libres (p>0,05), pero ácidos grasos libres y grasa mostró diferencias significativas (p

Como parte de la investigación que busca contribuir al estudio de los mecanismos de defensa que operan en la interacción clavel (Dianthus caryophyllus L.) - Fusarium oxysporum f. sp. dianthi, se evaluó la producción in vitro de metabolitos secundarios asociados con resistencia del clavel. Para ello se usaron cultivos de células en suspensión de variedades de clavel resistente (var. Candy) y susceptible (var. Rosana), elicitadas durante 3 y 15 días con dos elicitores bióticos, ácido fusárico y filtrado de medio de cultivo del hongo.

Polyphenoloxidase (PPO) was isolated and purified from stems of carnation (Dianthus caryophyllus L) after the inoculation with Fusarium oxysporum f. sp. dianthi race 2 (FOD2) of a tolerant variety. Purification was performed using column chromatography of ionic exchange, hydrophobic interaction and molecular exclusion. With these successive steps, a factor of 314 fold purification was achieved. The SDS-PAGE analysis showed one band of 40 kDa. The purified enzyme was partially characterized using cathecol as substrate and determined the optimal temperature as 45ºC and 7.5 as optimal pH. The enzyme showed a Michaelis-Menten kinetic with Km of 249 mM and Vmax 322 U/min. The IP was 5.0 indicating the acidic character of this protein. Using the purified enzyme and its reaction products, in vitro fungitoxic assays were realized indicating an important inhibitory activity against FOD2 of 57% at 24 hours. Then, it is possible to postulate that this enzyme is activated as a part of the defense mechanismsin this interaction model.

Some characteristics known as virulence factors for Colletotrichum sp. genus, like: weight of the produced mycelium, sporulation, poligalacturonase activity and pH medium were evaluated during the growth of C. gloeosporioides f. alatae in three liquid medium commonly used for fungi culture (Czapeck, Martin broth and potato broth) and additionally (Czapeck) with yam extract as the only source of carbon. After of 17 days of growth, maximum values were obtained for the above parameters in the last medium, compared with others growth media evaluated. The implemented medium with yam extract, supply nutritional requirements of the pathogen for the development of characteristic factors related with mechanism of infections that may play a role in the pathogenesis.

The reproduction of the sea cucumber Parastichopus parvimensis was studied from April 2000 to August 2001 at Isla Natividad and from March 2003 to March 2004 at Bahía Tortugas, Baja California Sur, Mexico. Samples were collected manually by semi-autonomous diving. The sea cucumber is a dioecious species, without external sexual dimorphism, with ramified gonad. The development of the gonad confirmed five stages: undifferentiated, gametogenesis, ripe, spawning, and post- spawning; this indicated annual synchronous reproduction in both study areas. The sex ratio was 1:1. The variation of the gonadosomatic index was directly related to the gonadal development. Maximum maturity and spawning were recorded from February to May at both sites. The weight at first maturity was 140 g at Isla Natividad and 120 g at Bahía Tortugas. In both areas P. parvimensis showed seasonal visceral atrophy from August to October. As a fishery management alternative, we propose one closed season from February to May to protect the reproductive season (ripe/spawning), and another from August to October to protect the period when the internal organs are absent or atrophied. [ABSTRACT FROM AUTHOR]

The oocyte structure of jumbo squid (Dosidicus gigas) female gonads was analyzed to validate morphochromatic sexual maturation stages based on a six-phase scale. Samples were obtained fortnightly from the Santa Rosalia area, Baja California Sur, from June 2001 to November 2002. Histological preparations were obtained from each gonad to count the number of oocytes at each level of development. The frequency of oocytes at each level was then used to estimate a maturity index (MI) to assess the correspondence between morphochromatic maturation stages and the oocyte structure in the gonad tissue. The histological analysis showed that morphochromatic stages I, II and III were ruled by oocytes in developmental level 2 or less (i.e., secondary growth has not yet begun), and thus correspond to sexually immature juveniles. Stages IV, V and VI were ruled by oocytes in more advanced developmental levels and correspond to mature or maturing adults. According to the analysis of variance, the morphochromatic maturity scale allowed sexually immature individuals to be readily and reliably distinguished from mature ones. A detailed analysis of MI confidence intervals showed that each morphochromatic maturity stage had a specific oocyte structure, except for stages II and III, which presented morphological differences. [ABSTRACT FROM AUTHOR]

Hepatocellular carcinoma (HCC) typically develops as a consequence of liver cirrhosis, but HCC epidemiology has evolved drastically in recent years. Metabolic dysfunction-associated steatotic liver disease (MASLD), including metabolic dysfunction-associated steatohepatitis, has emerged as the most common chronic liver disease worldwide and a leading cause of HCC. A substantial proportion of MASLD-associated HCC (MASLD-HCC) also can develop in patients without cirrhosis. The specific pathways that trigger carcinogenesis in this context are not elucidated completely, and recommendations for HCC surveillance in MASLD patients are challenging. In the era of precision medicine, it is critical to understand the processes that define the profiles of patients at increased risk of HCC in the MASLD setting, including cardiometabolic risk factors and the molecular targets that could be tackled effectively. Ideally, defining categories that encompass key pathophysiological features, associated with tailored diagnostic and treatment strategies, should facilitate the identification of specific MASLD-HCC phenotypes. In this review, we discuss MASLD-HCC, including its epidemiology and health care burden, the mechanistic data promoting MASLD, metabolic dysfunction-associated steatohepatitis, and MASLD-HCC. Its natural history, prognosis, and treatment are addressed specifically, as the role of metabolic phenotypes of MASLD-HCC as a potential strategy for risk stratification. The challenges in identifying high-risk patients and screening strategies also are discussed, as well as the potential approaches for MASLD-HCC prevention and treatment., (Copyright © 2024 AGA Institute. Published by Elsevier Inc. All rights reserved.)

The adult mammalian heart has been demonstrated to be endowed with low but real turnover capacity, especially for cardiomyocytes, the key functional cell type. The source, however, of that turnover capacity remains controversial. In this regard, we have defined and characterized a resident multipotent cardiac mouse progenitor population, Bmi1 +DR (for Bmi1 + Damage-Responsive cells). Bmi1 +DR is one of the cell types with the lowest ROS (Reactive Oxygen Species) levels in the adult heart, being particularly characterized by their close relationship with cardiac vessels, most probably involved in the regulation of proliferation/maintenance of Bmi1 +DR. This was proposed to work as their endothelial niche. Due to the scarcity of Bmi1 +DR cells in the adult mouse heart, we have generated an immortalization/dis-immortalization model using Simian Vacuolating Virus 40-Large Antigen T (SV40-T) to facilitate their in vitro characterization. We have obtained a heterogeneous population of immortalized Bmi1 +DR cells ( Bmi1 +DR IMM ) that was validated attending to different criteria, also showing a comparable sensitivity to strong oxidative damage. Then, we concluded that the Bmi1 -DR IMM population is an appropriate model for primary Bmi1 +DR in vitro studies. The co-culture of Bmi1 +DR IMM cells with endothelial cells protects them against oxidative damage, showing a moderate depletion in non-canonical autophagy and also contributing with a modest metabolic regulation.

Background: In the past decades, global changes, including hepatitis B vaccination, hepatitis B and C antiviral therapies, and the increasing prevalence of steatotic liver disease, have influenced the landscape of liver cancer etiologies., Methods: We performed a retrospective study focused on the etiological factors of de novo hepatocellular carcinoma (HCC) diagnoses in an academic center between 2019 and 2022., Results: Among 352 consecutive patients with HCC, alcohol-related liver disease was the predominant etiology (33.3%), followed by hepatitis C (HCV) infection (30.7%). Significant associations were found between HCC etiology and patient demographics, BCLC stage at diagnosis, and cirrhosis prevalence., Conclusions: Whereas accessibility to antiviral therapy is granted, HCV infection remains as one of the main HCC etiologies. MASLD-related HCC, although growing globally, is not as relevant in our area. Strong public policies need to be implemented to prevent alcohol consumption, the main etiology of liver disease and liver cancer.

Oxidative stress-induced myocardial apoptosis and necrosis are critically involved in ischemic infarction, and several sources of extracellular vesicles appear to be enriched in therapeutic activities. The central objective was to identify and validate the differential exosome miRNA repertoire in human cardiac progenitor cells (CPC). CPC exosomes were first analyzed by LC-MS/MS and compared by RNAseq with exomes of human mesenchymal stromal cells and human fibroblasts to define their differential exosome miRNA repertoire (exo-miR SEL ). Proteomics demonstrated a highly significant representation of cardiovascular development functions and angiogenesis in CPC exosomes, and RNAseq analysis yielded about 350 different miRNAs; among the exo-miR SEL population, miR-935 was confirmed as the miRNA most significantly up-regulated; interestingly, miR-935 was also found to be preferentially expressed in mouse primary cardiac Bmi1 +high CPC, a population highly enriched in progenitors. Furthermore, it was found that transfection of an miR-935 antagomiR combined with oxidative stress treatment provoked a significant increment both in apoptotic and necrotic populations, whereas transfection of a miR-935 mimic did not modify the response. Conclusion. miR-935 is a highly differentially expressed miRNA in exo-miR SEL , and its expression reduction promotes oxidative stress-associated apoptosis. MiR-935, together with other exosomal miRNA members, could counteract oxidative stress-related apoptosis, at least in CPC surroundings.

Background: Cell-free DNA (cfDNA) concentrations have been described to be inversely correlated with prognosis in cancer. Mutations in HCC-associated driver genes in cfDNA have been reported, but their relation with patient's outcome has not been described. Our aim was to elucidate whether mutations found in cfDNA could be representative from those present in HCC tissue, providing the rationale to use the cfDNA to monitor HCC., Methods: Tumoral tissue, paired nontumor adjacent tissue and blood samples were collected from 30 HCC patients undergoing curative therapies. Deep sequencing targeting HCC driver genes was performed., Results: Patients with more than 2 ng/µL of cfDNA at diagnosis had higher mortality (mean OS 24.6 vs. 31.87 months, p = 0.01) (AUC = 0.782). Subjects who died during follow-up, had a significantly higher number of mutated genes ( p = 0.015) and number of mutations ( p = 0.015) on cfDNA. Number of mutated genes ( p = 0.001), detected mutations ( p = 0.001) in cfDNA and ratio (number of mutations/cfDNA) ( p = 0.003) were significantly associated with recurrence. However, patients with a ratio (number of mutations/cfDNA) above 6 (long-rank p = 0.0003) presented a higher risk of recurrence than those with a ratio under 6. Detection of more than four mutations in cfDNA correlated with higher risk of death (long-rank p = 0.042)., Conclusions: In summary, cfDNA and detection of prevalent HCC mutations could have prognostic implications in early-stage HCC patients.

Since 2020, the world has been immersed in a change in lifestyle (social, lifestyle, nutri-tion and physical activity patterns), due to the appearance of COVID-19 and the strict mobility measures which were implemented to prevent its spread. All these changes had a nutritional impact on people, modifying their dietary guidelines. This cross-sectional study was carried out to assess whether dietary habits, lifestyle, and adherence to the Mediterranean diet among the Spanish adult population (25-65 years old) during confinement was modified during the post-confinement period, using an e-survey through social networks, involving 510 subjects. A decrease in the intake of ultra-processed products, with a correlation between weekly food delivery orders at home and the consumption of salty snacks, sugary drinks, and processed pastries was also recorded. Most of the subjects performed physical exercise on a regular basis, maintaining the body weight in half of the participants. During the post-confinement period a substantial proportion of the population had healthy lifestyle and dietary habits, including the adequate consumption of fruits, vegetables and legumes; adequate time was spent preparing meals and the population did not regularly order food at home, which in the long term, reduced the risk of several diseases.

ARMCX3 is encoded by a member of the Armcx gene family and is known to be involved in nervous system development and function. We found that ARMCX3 is markedly upregulated in mouse liver in response to high lipid availability, and that hepatic ARMCX3 is upregulated in patients with NAFLD and hepatocellular carcinoma (HCC). Mice were subjected to ARMCX3 invalidation (inducible ARMCX3 knockout) and then exposed to a high-fat diet and diethylnitrosamine-induced hepatocarcinogenesis. The effects of experimental ARMCX3 knockdown or overexpression in HCC cell lines were also analyzed. ARMCX3 invalidation protected mice against high-fat-diet-induced NAFLD and chemically induced hepatocarcinogenesis. ARMCX3 invalidation promoted apoptotic cell death and macrophage infiltration in livers of diethylnitrosamine-treated mice maintained on a high-fat diet. ARMCX3 downregulation reduced the viability, clonality and migration of HCC cell lines, whereas ARMCX3 overexpression caused the reciprocal effects. SOX9 was found to mediate the effects of ARMCX3 in hepatic cells, with the SOX9 interaction required for the effects of ARMCX3 on hepatic cell proliferation. In conclusion, ARMCX3 is identified as a novel molecular actor in liver physiopathology and carcinogenesis. ARMCX3 downregulation appears to protect against hepatocarcinogenesis, especially under conditions of high dietary lipid-mediated hepatic insult.

Nathan H. Azrin (1930-2013) contributed extensively to the fields of experimental and applied behavior analysis. His creative and prolific research programs covered a wide range of experimental and applied areas that resulted in 160 articles and several books published over a period of almost 6 decades. As a result, his career illustrates an unparalleled example of translational work in behavior analysis, which has had a major impact not only within our field, but across disciplines and outside academia. In the current article we present a summary of Azrin's wide ranging contributions in the areas of punishment, behavioral engineering, conditioned reinforcement and token economies, feeding disorders, toilet training, overcorrection, habit disorders, in-class behavior, job finding, marital therapy, and substance abuse. In addition, we use scientometric evidence to gain an insight on Azrin's general approach to treatment evaluation and programmatic research. The analysis of Azrin's approach to research, we believe, holds important lessons to behavior analysts today with an interest in the applied and translational sectors of our science., Supplementary Information: The online version contains supplementary material available at 10.1007/s40614-020-00278-4., (© Association for Behavior Analysis International 2021.)

Obesity, which is a worldwide epidemic, confers increased risk for multiple serious conditions including type 2 diabetes, nonalcoholic fatty liver disease, and cardiovascular diseases. Adipose tissue is considered one of the largest endocrine organs in the body as well as an active tissue for cellular reactions and metabolic homeostasis rather than an inert tissue only for energy storage. The functional pleiotropism of adipose tissue relies on its ability to synthesize and release a large number of hormones, cytokines, extracellular matrix proteins, and growth and vasoactive factors, which are collectively called adipokines known to influence a variety of physiological and pathophysiological processes. In the obese state, excessive visceral fat accumulation causes adipose tissue dysfunctionality that strongly contributes to the onset of obesity-related comorbidities. The mechanisms underlying adipose tissue dysfunction include adipocyte hypertrophy and hyperplasia, increased inflammation, impaired extracellular matrix remodeling, and fibrosis together with an altered secretion of adipokines. This review describes the relevance of specific adipokines in the obesity-associated cardiovascular disease.

Background & Aims: Cirrhosis and chronic inflammation precede development of hepatocellular carcinoma (HCC) in approximately 80% of cases. We investigated immune-related gene expression patterns in liver tissues surrounding early-stage HCCs and chemopreventive agents that might alter these patterns to prevent liver tumorigenesis., Methods: We analyzed gene expression profiles of nontumor liver tissues from 392 patients with early-stage HCC (training set, N = 167 and validation set, N = 225) and liver tissue from patients with cirrhosis without HCC (N = 216, controls) to identify changes in expression of genes that regulate the immune response that could contribute to hepatocarcinogenesis. We defined 172 genes as markers for this deregulated immune response, which we called the immune-mediated cancer field (ICF). We analyzed the expression data of liver tissues from 216 patients with cirrhosis without HCC and investigated the association between this gene expression signature and development of HCC and outcomes of patients (median follow-up, 10 years). Human liver tissues were also analyzed by histology. C57BL/6J mice were given a single injection of diethylnitrosamine (DEN) followed by weekly doses of carbon tetrachloride to induce liver fibrosis and tumorigenesis. Mice were then orally given the multiple tyrosine inhibitor nintedanib or vehicle (controls); liver tissues were collected and histology, transcriptome, and protein analyses were performed. We also analyzed transcriptomes of liver tissues collected from mice on a choline-deficient high-fat diet, which developed chronic liver inflammation and tumors, orally given aspirin and clopidogrel or the anti-inflammatory agent sulindac vs mice on a chow (control) diet., Results: We found the ICF gene expression pattern in 50% of liver tissues from patients with cirrhosis without HCC and in 60% of nontumor liver tissues from patients with early-stage HCC. The liver tissues with the ICF gene expression pattern had 3 different features: increased numbers of effector T cells; increased expression of genes that suppress the immune response and activation of transforming growth factor β signaling; or expression of genes that promote inflammation and activation of interferon gamma signaling. Patients with cirrhosis and liver tissues with the immunosuppressive profile (10% of cases) had a higher risk of HCC (hazard ratio, 2.41; 95% confidence interval, 1.21-4.80). Mice with chemically induced fibrosis or diet-induced steatohepatitis given nintedanib or aspirin and clopidogrel down-regulated the ICF gene expression pattern in liver and developed fewer and smaller tumors than mice given vehicle., Conclusions: We identified an immune-related gene expression pattern in liver tissues of patients with early-stage HCC, called the ICF, that is associated with risk of HCC development in patients with cirrhosis. Administration of nintedanib or aspirin and clopidogrel to mice with chronic liver inflammation caused loss of this gene expression pattern and development of fewer and smaller liver tumors. Agents that alter immune regulatory gene expression patterns associated with carcinogenesis might be tested as chemopreventive agents in patients with cirrhosis., (Copyright © 2019 AGA Institute. Published by Elsevier Inc. All rights reserved.)